**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains C code routines that used to generate VDBE code
** that implements the ALTER TABLE command.
**
** $Id: alter.c,v 1.27 2007/06/27 17:09:24 danielk1977 Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>

/*
** The code in this file only exists if we are not omitting the
** ALTER TABLE logic from the build.
................................................................................
    for( pTrig=pTab->pTrigger; pTrig; pTrig=pTrig->pNext ){
      if( pTrig->pSchema==pTempSchema ){
        if( !zWhere ){
          zWhere = sqlite3MPrintf("name=%Q", pTrig->name);
        }else{
          tmp = zWhere;
          zWhere = sqlite3MPrintf("%s OR name=%Q", zWhere, pTrig->name);
          sqliteFree(tmp);
        }
      }
    }
  }
  return zWhere;
}

................................................................................
  const char *zTabName;     /* Original name of the table */
  Vdbe *v;
#ifndef SQLITE_OMIT_TRIGGER
  char *zWhere = 0;         /* Where clause to locate temp triggers */
#endif
  int isVirtualRename = 0;  /* True if this is a v-table with an xRename() */
  
  if( sqlite3MallocFailed() ) goto exit_rename_table;
  assert( pSrc->nSrc==1 );

  pTab = sqlite3LocateTable(pParse, pSrc->a[0].zName, pSrc->a[0].zDatabase);
  if( !pTab ) goto exit_rename_table;
  iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema);
  zDb = db->aDb[iDb].zName;

  /* Get a NULL terminated version of the new table name. */
  zName = sqlite3NameFromToken(pName);
  if( !zName ) goto exit_rename_table;

  /* Check that a table or index named 'zName' does not already exist
  ** in database iDb. If so, this is an error.
  */
  if( sqlite3FindTable(db, zName, zDb) || sqlite3FindIndex(db, zName, zDb) ){
    sqlite3ErrorMsg(pParse, 
................................................................................
  */
  if( (zWhere=whereTempTriggers(pParse, pTab))!=0 ){
    sqlite3NestedParse(pParse, 
        "UPDATE sqlite_temp_master SET "
            "sql = sqlite_rename_trigger(sql, %Q), "
            "tbl_name = %Q "
            "WHERE %s;", zName, zName, zWhere);
    sqliteFree(zWhere);
  }
#endif

  /* Drop and reload the internal table schema. */
  reloadTableSchema(pParse, pTab, zName);

exit_rename_table:
  sqlite3SrcListDelete(pSrc);
  sqliteFree(zName);
}


/*
** This function is called after an "ALTER TABLE ... ADD" statement
** has been parsed. Argument pColDef contains the text of the new
** column definition.
................................................................................
  Table *pTab;              /* Table being altered */
  int iDb;                  /* Database number */
  const char *zDb;          /* Database name */
  const char *zTab;         /* Table name */
  char *zCol;               /* Null-terminated column definition */
  Column *pCol;             /* The new column */
  Expr *pDflt;              /* Default value for the new column */


  if( pParse->nErr ) return;
  pNew = pParse->pNewTable;
  assert( pNew );


  iDb = sqlite3SchemaToIndex(pParse->db, pNew->pSchema);
  zDb = pParse->db->aDb[iDb].zName;
  zTab = pNew->zName;
  pCol = &pNew->aCol[pNew->nCol-1];
  pDflt = pCol->pDflt;
  pTab = sqlite3FindTable(pParse->db, zTab, zDb);
  assert( pTab );

#ifndef SQLITE_OMIT_AUTHORIZATION
  /* Invoke the authorization callback. */
  if( sqlite3AuthCheck(pParse, SQLITE_ALTER_TABLE, zDb, pTab->zName, 0) ){
    return;
  }
................................................................................

  /* Ensure the default expression is something that sqlite3ValueFromExpr()
  ** can handle (i.e. not CURRENT_TIME etc.)
  */
  if( pDflt ){
    sqlite3_value *pVal;
    if( sqlite3ValueFromExpr(pDflt, SQLITE_UTF8, SQLITE_AFF_NONE, &pVal) ){
      /* malloc() has failed */
      return;
    }
    if( !pVal ){
      sqlite3ErrorMsg(pParse, "Cannot add a column with non-constant default");
      return;
    }
    sqlite3ValueFree(pVal);
  }

  /* Modify the CREATE TABLE statement. */
  zCol = sqliteStrNDup((char*)pColDef->z, pColDef->n);
  if( zCol ){
    char *zEnd = &zCol[pColDef->n-1];
    while( (zEnd>zCol && *zEnd==';') || isspace(*(unsigned char *)zEnd) ){
      *zEnd-- = '\0';
    }
    sqlite3NestedParse(pParse, 
        "UPDATE %Q.%s SET "
          "sql = substr(sql,1,%d) || ', ' || %Q || substr(sql,%d,length(sql)) "
        "WHERE type = 'table' AND name = %Q", 
      zDb, SCHEMA_TABLE(iDb), pNew->addColOffset, zCol, pNew->addColOffset+1,
      zTab
    );
    sqliteFree(zCol);
  }

  /* If the default value of the new column is NULL, then set the file
  ** format to 2. If the default value of the new column is not NULL,
  ** the file format becomes 3.
  */
  sqlite3MinimumFileFormat(pParse, iDb, pDflt ? 3 : 2);
................................................................................
void sqlite3AlterBeginAddColumn(Parse *pParse, SrcList *pSrc){
  Table *pNew;
  Table *pTab;
  Vdbe *v;
  int iDb;
  int i;
  int nAlloc;


  /* Look up the table being altered. */
  assert( pParse->pNewTable==0 );
  if( sqlite3MallocFailed() ) goto exit_begin_add_column;
  pTab = sqlite3LocateTable(pParse, pSrc->a[0].zName, pSrc->a[0].zDatabase);
  if( !pTab ) goto exit_begin_add_column;

#ifndef SQLITE_OMIT_VIRTUALTABLE
  if( IsVirtual(pTab) ){
    sqlite3ErrorMsg(pParse, "virtual tables may not be altered");
    goto exit_begin_add_column;
................................................................................
  /* Make sure this is not an attempt to ALTER a view. */
  if( pTab->pSelect ){
    sqlite3ErrorMsg(pParse, "Cannot add a column to a view");
    goto exit_begin_add_column;
  }

  assert( pTab->addColOffset>0 );
  iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema);

  /* Put a copy of the Table struct in Parse.pNewTable for the
  ** sqlite3AddColumn() function and friends to modify.
  */
  pNew = (Table *)sqliteMalloc(sizeof(Table));
  if( !pNew ) goto exit_begin_add_column;
  pParse->pNewTable = pNew;
  pNew->nRef = 1;
  pNew->nCol = pTab->nCol;
  assert( pNew->nCol>0 );
  nAlloc = (((pNew->nCol-1)/8)*8)+8;
  assert( nAlloc>=pNew->nCol && nAlloc%8==0 && nAlloc-pNew->nCol<8 );
  pNew->aCol = (Column *)sqliteMalloc(sizeof(Column)*nAlloc);
  pNew->zName = sqliteStrDup(pTab->zName);
  if( !pNew->aCol || !pNew->zName ){

    goto exit_begin_add_column;
  }
  memcpy(pNew->aCol, pTab->aCol, sizeof(Column)*pNew->nCol);
  for(i=0; i<pNew->nCol; i++){
    Column *pCol = &pNew->aCol[i];
    pCol->zName = sqliteStrDup(pCol->zName);
    pCol->zColl = 0;
    pCol->zType = 0;
    pCol->pDflt = 0;
  }
  pNew->pSchema = pParse->db->aDb[iDb].pSchema;
  pNew->addColOffset = pTab->addColOffset;
  pNew->nRef = 1;

  /* Begin a transaction and increment the schema cookie.  */
  sqlite3BeginWriteOperation(pParse, 0, iDb);
  v = sqlite3GetVdbe(pParse);
  if( !v ) goto exit_begin_add_column;
  sqlite3ChangeCookie(pParse->db, v, iDb);

exit_begin_add_column:
  sqlite3SrcListDelete(pSrc);
  return;
}
#endif  /* SQLITE_ALTER_TABLE */

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains C code routines that used to generate VDBE code
** that implements the ALTER TABLE command.
**
** $Id: alter.c,v 1.28 2007/08/16 04:30:39 drh Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>

/*
** The code in this file only exists if we are not omitting the
** ALTER TABLE logic from the build.
................................................................................
    for( pTrig=pTab->pTrigger; pTrig; pTrig=pTrig->pNext ){
      if( pTrig->pSchema==pTempSchema ){
        if( !zWhere ){
          zWhere = sqlite3MPrintf("name=%Q", pTrig->name);
        }else{
          tmp = zWhere;
          zWhere = sqlite3MPrintf("%s OR name=%Q", zWhere, pTrig->name);
          sqlite3_free(tmp);
        }
      }
    }
  }
  return zWhere;
}

................................................................................
  const char *zTabName;     /* Original name of the table */
  Vdbe *v;
#ifndef SQLITE_OMIT_TRIGGER
  char *zWhere = 0;         /* Where clause to locate temp triggers */
#endif
  int isVirtualRename = 0;  /* True if this is a v-table with an xRename() */
  
  if( db->mallocFailed ) goto exit_rename_table;
  assert( pSrc->nSrc==1 );

  pTab = sqlite3LocateTable(pParse, pSrc->a[0].zName, pSrc->a[0].zDatabase);
  if( !pTab ) goto exit_rename_table;
  iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema);
  zDb = db->aDb[iDb].zName;

  /* Get a NULL terminated version of the new table name. */
  zName = sqlite3NameFromToken(db, pName);
  if( !zName ) goto exit_rename_table;

  /* Check that a table or index named 'zName' does not already exist
  ** in database iDb. If so, this is an error.
  */
  if( sqlite3FindTable(db, zName, zDb) || sqlite3FindIndex(db, zName, zDb) ){
    sqlite3ErrorMsg(pParse, 
................................................................................
  */
  if( (zWhere=whereTempTriggers(pParse, pTab))!=0 ){
    sqlite3NestedParse(pParse, 
        "UPDATE sqlite_temp_master SET "
            "sql = sqlite_rename_trigger(sql, %Q), "
            "tbl_name = %Q "
            "WHERE %s;", zName, zName, zWhere);
    sqlite3_free(zWhere);
  }
#endif

  /* Drop and reload the internal table schema. */
  reloadTableSchema(pParse, pTab, zName);

exit_rename_table:
  sqlite3SrcListDelete(pSrc);
  sqlite3_free(zName);
}


/*
** This function is called after an "ALTER TABLE ... ADD" statement
** has been parsed. Argument pColDef contains the text of the new
** column definition.
................................................................................
  Table *pTab;              /* Table being altered */
  int iDb;                  /* Database number */
  const char *zDb;          /* Database name */
  const char *zTab;         /* Table name */
  char *zCol;               /* Null-terminated column definition */
  Column *pCol;             /* The new column */
  Expr *pDflt;              /* Default value for the new column */
  sqlite3 *db;              /* The database connection; */

  if( pParse->nErr ) return;
  pNew = pParse->pNewTable;
  assert( pNew );

  db = pParse->db;
  iDb = sqlite3SchemaToIndex(db, pNew->pSchema);
  zDb = db->aDb[iDb].zName;
  zTab = pNew->zName;
  pCol = &pNew->aCol[pNew->nCol-1];
  pDflt = pCol->pDflt;
  pTab = sqlite3FindTable(db, zTab, zDb);
  assert( pTab );

#ifndef SQLITE_OMIT_AUTHORIZATION
  /* Invoke the authorization callback. */
  if( sqlite3AuthCheck(pParse, SQLITE_ALTER_TABLE, zDb, pTab->zName, 0) ){
    return;
  }
................................................................................

  /* Ensure the default expression is something that sqlite3ValueFromExpr()
  ** can handle (i.e. not CURRENT_TIME etc.)
  */
  if( pDflt ){
    sqlite3_value *pVal;
    if( sqlite3ValueFromExpr(pDflt, SQLITE_UTF8, SQLITE_AFF_NONE, &pVal) ){
      db->mallocFailed = 1;
      return;
    }
    if( !pVal ){
      sqlite3ErrorMsg(pParse, "Cannot add a column with non-constant default");
      return;
    }
    sqlite3ValueFree(pVal);
  }

  /* Modify the CREATE TABLE statement. */
  zCol = sqlite3DbStrNDup(db, (char*)pColDef->z, pColDef->n);
  if( zCol ){
    char *zEnd = &zCol[pColDef->n-1];
    while( (zEnd>zCol && *zEnd==';') || isspace(*(unsigned char *)zEnd) ){
      *zEnd-- = '\0';
    }
    sqlite3NestedParse(pParse, 
        "UPDATE %Q.%s SET "
          "sql = substr(sql,1,%d) || ', ' || %Q || substr(sql,%d,length(sql)) "
        "WHERE type = 'table' AND name = %Q", 
      zDb, SCHEMA_TABLE(iDb), pNew->addColOffset, zCol, pNew->addColOffset+1,
      zTab
    );
    sqlite3_free(zCol);
  }

  /* If the default value of the new column is NULL, then set the file
  ** format to 2. If the default value of the new column is not NULL,
  ** the file format becomes 3.
  */
  sqlite3MinimumFileFormat(pParse, iDb, pDflt ? 3 : 2);
................................................................................
void sqlite3AlterBeginAddColumn(Parse *pParse, SrcList *pSrc){
  Table *pNew;
  Table *pTab;
  Vdbe *v;
  int iDb;
  int i;
  int nAlloc;
  sqlite3 *db = pParse->db;

  /* Look up the table being altered. */
  assert( pParse->pNewTable==0 );
  if( db->mallocFailed ) goto exit_begin_add_column;
  pTab = sqlite3LocateTable(pParse, pSrc->a[0].zName, pSrc->a[0].zDatabase);
  if( !pTab ) goto exit_begin_add_column;

#ifndef SQLITE_OMIT_VIRTUALTABLE
  if( IsVirtual(pTab) ){
    sqlite3ErrorMsg(pParse, "virtual tables may not be altered");
    goto exit_begin_add_column;
................................................................................
  /* Make sure this is not an attempt to ALTER a view. */
  if( pTab->pSelect ){
    sqlite3ErrorMsg(pParse, "Cannot add a column to a view");
    goto exit_begin_add_column;
  }

  assert( pTab->addColOffset>0 );
  iDb = sqlite3SchemaToIndex(db, pTab->pSchema);

  /* Put a copy of the Table struct in Parse.pNewTable for the
  ** sqlite3AddColumn() function and friends to modify.
  */
  pNew = (Table*)sqlite3DbMallocZero(db, sizeof(Table));
  if( !pNew ) goto exit_begin_add_column;
  pParse->pNewTable = pNew;
  pNew->nRef = 1;
  pNew->nCol = pTab->nCol;
  assert( pNew->nCol>0 );
  nAlloc = (((pNew->nCol-1)/8)*8)+8;
  assert( nAlloc>=pNew->nCol && nAlloc%8==0 && nAlloc-pNew->nCol<8 );
  pNew->aCol = (Column*)sqlite3_malloc(sizeof(Column)*nAlloc);
  pNew->zName = sqlite3DbStrDup(db, pTab->zName);
  if( !pNew->aCol || !pNew->zName ){
    db->mallocFailed = 1;
    goto exit_begin_add_column;
  }
  memcpy(pNew->aCol, pTab->aCol, sizeof(Column)*pNew->nCol);
  for(i=0; i<pNew->nCol; i++){
    Column *pCol = &pNew->aCol[i];
    pCol->zName = sqlite3DbStrDup(db, pCol->zName);
    pCol->zColl = 0;
    pCol->zType = 0;
    pCol->pDflt = 0;
  }
  pNew->pSchema = db->aDb[iDb].pSchema;
  pNew->addColOffset = pTab->addColOffset;
  pNew->nRef = 1;

  /* Begin a transaction and increment the schema cookie.  */
  sqlite3BeginWriteOperation(pParse, 0, iDb);
  v = sqlite3GetVdbe(pParse);
  if( !v ) goto exit_begin_add_column;
  sqlite3ChangeCookie(db, v, iDb);

exit_begin_add_column:
  sqlite3SrcListDelete(pSrc);
  return;
}
#endif  /* SQLITE_ALTER_TABLE */

**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains code associated with the ANALYZE command.
**
** @(#) $Id: analyze.c,v 1.19 2007/06/20 13:37:31 drh Exp $
*/
#ifndef SQLITE_OMIT_ANALYZE
#include "sqliteInt.h"

/*
** This routine generates code that opens the sqlite_stat1 table on cursor
** iStatCur.
................................................................................
    }
  }else if( pName2==0 || pName2->n==0 ){
    /* Form 2:  Analyze the database or table named */
    iDb = sqlite3FindDb(db, pName1);
    if( iDb>=0 ){
      analyzeDatabase(pParse, iDb);
    }else{
      z = sqlite3NameFromToken(pName1);
      pTab = sqlite3LocateTable(pParse, z, 0);
      sqliteFree(z);
      if( pTab ){
        analyzeTable(pParse, pTab);
      }
    }
  }else{
    /* Form 3: Analyze the fully qualified table name */
    iDb = sqlite3TwoPartName(pParse, pName1, pName2, &pTableName);
    if( iDb>=0 ){
      zDb = db->aDb[iDb].zName;
      z = sqlite3NameFromToken(pTableName);
      if( z ){
        pTab = sqlite3LocateTable(pParse, z, zDb);
        sqliteFree(z);
        if( pTab ){
          analyzeTable(pParse, pTab);
        }
      }
    }   
  }
}
................................................................................

  /* Load new statistics out of the sqlite_stat1 table */
  zSql = sqlite3MPrintf("SELECT idx, stat FROM %Q.sqlite_stat1",
                        sInfo.zDatabase);
  sqlite3SafetyOff(db);
  rc = sqlite3_exec(db, zSql, analysisLoader, &sInfo, 0);
  sqlite3SafetyOn(db);
  sqliteFree(zSql);
  return rc;
}


#endif /* SQLITE_OMIT_ANALYZE */

**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains code associated with the ANALYZE command.
**
** @(#) $Id: analyze.c,v 1.20 2007/08/16 04:30:39 drh Exp $
*/
#ifndef SQLITE_OMIT_ANALYZE
#include "sqliteInt.h"

/*
** This routine generates code that opens the sqlite_stat1 table on cursor
** iStatCur.
................................................................................
    }
  }else if( pName2==0 || pName2->n==0 ){
    /* Form 2:  Analyze the database or table named */
    iDb = sqlite3FindDb(db, pName1);
    if( iDb>=0 ){
      analyzeDatabase(pParse, iDb);
    }else{
      z = sqlite3NameFromToken(db, pName1);
      pTab = sqlite3LocateTable(pParse, z, 0);
      sqlite3_free(z);
      if( pTab ){
        analyzeTable(pParse, pTab);
      }
    }
  }else{
    /* Form 3: Analyze the fully qualified table name */
    iDb = sqlite3TwoPartName(pParse, pName1, pName2, &pTableName);
    if( iDb>=0 ){
      zDb = db->aDb[iDb].zName;
      z = sqlite3NameFromToken(db, pTableName);
      if( z ){
        pTab = sqlite3LocateTable(pParse, z, zDb);
        sqlite3_free(z);
        if( pTab ){
          analyzeTable(pParse, pTab);
        }
      }
    }   
  }
}
................................................................................

  /* Load new statistics out of the sqlite_stat1 table */
  zSql = sqlite3MPrintf("SELECT idx, stat FROM %Q.sqlite_stat1",
                        sInfo.zDatabase);
  sqlite3SafetyOff(db);
  rc = sqlite3_exec(db, zSql, analysisLoader, &sInfo, 0);
  sqlite3SafetyOn(db);
  sqlite3_free(zSql);
  return rc;
}


#endif /* SQLITE_OMIT_ANALYZE */

**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains code used to implement the ATTACH and DETACH commands.
**
** $Id: attach.c,v 1.60 2007/05/09 20:31:30 drh Exp $
*/
#include "sqliteInt.h"

#ifndef SQLITE_OMIT_ATTACH
/*
** Resolve an expression that was part of an ATTACH or DETACH statement. This
** is slightly different from resolving a normal SQL expression, because simple
................................................................................
    sqlite3_snprintf(sizeof(zErr), zErr,
                     "cannot ATTACH database within transaction");
    goto attach_error;
  }
  for(i=0; i<db->nDb; i++){
    char *z = db->aDb[i].zName;
    if( z && zName && sqlite3StrICmp(z, zName)==0 ){

      sqlite3_snprintf(sizeof(zErr), zErr, "database %s is already in use", zName);
      goto attach_error;
    }
  }

  /* Allocate the new entry in the db->aDb[] array and initialise the schema
  ** hash tables.
  */
  if( db->aDb==db->aDbStatic ){
    aNew = sqliteMalloc( sizeof(db->aDb[0])*3 );
    if( aNew==0 ){

      return;
    }
    memcpy(aNew, db->aDb, sizeof(db->aDb[0])*2);
  }else{
    aNew = sqliteRealloc(db->aDb, sizeof(db->aDb[0])*(db->nDb+1) );
    if( aNew==0 ){

      return;
    } 
  }
  db->aDb = aNew;
  aNew = &db->aDb[db->nDb++];
  memset(aNew, 0, sizeof(*aNew));

  /* Open the database file. If the btree is successfully opened, use
  ** it to obtain the database schema. At this point the schema may
  ** or may not be initialised.
  */
  rc = sqlite3BtreeFactory(db, zFile, 0, SQLITE_DEFAULT_CACHE_SIZE, &aNew->pBt);
  if( rc==SQLITE_OK ){
    aNew->pSchema = sqlite3SchemaGet(aNew->pBt);
    if( !aNew->pSchema ){
      rc = SQLITE_NOMEM;
    }else if( aNew->pSchema->file_format && aNew->pSchema->enc!=ENC(db) ){
      sqlite3_snprintf(sizeof(zErr), zErr, 
        "attached databases must use the same text encoding as main database");
      goto attach_error;
    }
    sqlite3PagerLockingMode(sqlite3BtreePager(aNew->pBt), db->dfltLockMode);
  }
  aNew->zName = sqliteStrDup(zName);
  aNew->safety_level = 3;

#if SQLITE_HAS_CODEC
  {
    extern int sqlite3CodecAttach(sqlite3*, int, const void*, int);
    extern void sqlite3CodecGetKey(sqlite3*, int, void**, int*);
    int nKey;
    char *zKey;
    int t = sqlite3_value_type(argv[2]);
    switch( t ){
      case SQLITE_INTEGER:
      case SQLITE_FLOAT:
        zErrDyn = sqliteStrDup("Invalid key value");
        rc = SQLITE_ERROR;
        break;
        
      case SQLITE_TEXT:
      case SQLITE_BLOB:
        nKey = sqlite3_value_bytes(argv[2]);
        zKey = (char *)sqlite3_value_blob(argv[2]);
................................................................................
      sqlite3BtreeClose(db->aDb[iDb].pBt);
      db->aDb[iDb].pBt = 0;
      db->aDb[iDb].pSchema = 0;
    }
    sqlite3ResetInternalSchema(db, 0);
    db->nDb = iDb;
    if( rc==SQLITE_NOMEM ){
      sqlite3FailedMalloc();
      sqlite3_snprintf(sizeof(zErr),zErr, "out of memory");
    }else{
      sqlite3_snprintf(sizeof(zErr),zErr, "unable to open database: %s", zFile);
    }
    goto attach_error;
  }
  
  return;

attach_error:
  /* Return an error if we get here */
  if( zErrDyn ){
    sqlite3_result_error(context, zErrDyn, -1);
    sqliteFree(zErrDyn);
  }else{
    zErr[sizeof(zErr)-1] = 0;
    sqlite3_result_error(context, zErr, -1);
  }
}

/*
................................................................................
  int rc;
  NameContext sName;
  Vdbe *v;
  FuncDef *pFunc;
  sqlite3* db = pParse->db;

#ifndef SQLITE_OMIT_AUTHORIZATION
  assert( sqlite3MallocFailed() || pAuthArg );
  if( pAuthArg ){
    char *zAuthArg = sqlite3NameFromToken(&pAuthArg->span);
    if( !zAuthArg ){
      goto attach_end;
    }
    rc = sqlite3AuthCheck(pParse, type, zAuthArg, 0, 0);
    sqliteFree(zAuthArg);
    if(rc!=SQLITE_OK ){
      goto attach_end;
    }
  }
#endif /* SQLITE_OMIT_AUTHORIZATION */

  memset(&sName, 0, sizeof(NameContext));
................................................................................
  }

  v = sqlite3GetVdbe(pParse);
  sqlite3ExprCode(pParse, pFilename);
  sqlite3ExprCode(pParse, pDbname);
  sqlite3ExprCode(pParse, pKey);

  assert( v || sqlite3MallocFailed() );
  if( v ){
    sqlite3VdbeAddOp(v, OP_Function, 0, nFunc);
    pFunc = sqlite3FindFunction(db, zFunc, strlen(zFunc), nFunc, SQLITE_UTF8,0);
    sqlite3VdbeChangeP3(v, -1, (char *)pFunc, P3_FUNCDEF);

    /* Code an OP_Expire. For an ATTACH statement, set P1 to true (expire this
    ** statement only). For DETACH, set it to false (expire all existing
................................................................................
  const char *zDb;
  struct SrcList_item *pItem;

  if( pList==0 ) return 0;
  zDb = pFix->zDb;
  for(i=0, pItem=pList->a; i<pList->nSrc; i++, pItem++){
    if( pItem->zDatabase==0 ){
      pItem->zDatabase = sqliteStrDup(zDb);
    }else if( sqlite3StrICmp(pItem->zDatabase,zDb)!=0 ){
      sqlite3ErrorMsg(pFix->pParse,
         "%s %T cannot reference objects in database %s",
         pFix->zType, pFix->pName, pItem->zDatabase);
      return 1;
    }
#if !defined(SQLITE_OMIT_VIEW) || !defined(SQLITE_OMIT_TRIGGER)

**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains code used to implement the ATTACH and DETACH commands.
**
** $Id: attach.c,v 1.61 2007/08/16 04:30:39 drh Exp $
*/
#include "sqliteInt.h"

#ifndef SQLITE_OMIT_ATTACH
/*
** Resolve an expression that was part of an ATTACH or DETACH statement. This
** is slightly different from resolving a normal SQL expression, because simple
................................................................................
    sqlite3_snprintf(sizeof(zErr), zErr,
                     "cannot ATTACH database within transaction");
    goto attach_error;
  }
  for(i=0; i<db->nDb; i++){
    char *z = db->aDb[i].zName;
    if( z && zName && sqlite3StrICmp(z, zName)==0 ){
      sqlite3_snprintf(sizeof(zErr), zErr, 
                       "database %s is already in use", zName);
      goto attach_error;
    }
  }

  /* Allocate the new entry in the db->aDb[] array and initialise the schema
  ** hash tables.
  */
  if( db->aDb==db->aDbStatic ){
    aNew = sqlite3_malloc( sizeof(db->aDb[0])*3 );
    if( aNew==0 ){
      db->mallocFailed = 1;
      return;
    }
    memcpy(aNew, db->aDb, sizeof(db->aDb[0])*2);
  }else{
    aNew = sqlite3_realloc(db->aDb, sizeof(db->aDb[0])*(db->nDb+1) );
    if( aNew==0 ){
      db->mallocFailed = 1;
      return;
    } 
  }
  db->aDb = aNew;
  aNew = &db->aDb[db->nDb++];
  memset(aNew, 0, sizeof(*aNew));

  /* Open the database file. If the btree is successfully opened, use
  ** it to obtain the database schema. At this point the schema may
  ** or may not be initialised.
  */
  rc = sqlite3BtreeFactory(db, zFile, 0, SQLITE_DEFAULT_CACHE_SIZE, &aNew->pBt);
  if( rc==SQLITE_OK ){
    aNew->pSchema = sqlite3SchemaGet(db, aNew->pBt);
    if( !aNew->pSchema ){
      rc = SQLITE_NOMEM;
    }else if( aNew->pSchema->file_format && aNew->pSchema->enc!=ENC(db) ){
      sqlite3_snprintf(sizeof(zErr), zErr, 
        "attached databases must use the same text encoding as main database");
      goto attach_error;
    }
    sqlite3PagerLockingMode(sqlite3BtreePager(aNew->pBt), db->dfltLockMode);
  }
  aNew->zName = sqlite3DbStrDup(db, zName);
  aNew->safety_level = 3;

#if SQLITE_HAS_CODEC
  {
    extern int sqlite3CodecAttach(sqlite3*, int, const void*, int);
    extern void sqlite3CodecGetKey(sqlite3*, int, void**, int*);
    int nKey;
    char *zKey;
    int t = sqlite3_value_type(argv[2]);
    switch( t ){
      case SQLITE_INTEGER:
      case SQLITE_FLOAT:
        zErrDyn = sqlite3DbStrDup(db, "Invalid key value");
        rc = SQLITE_ERROR;
        break;
        
      case SQLITE_TEXT:
      case SQLITE_BLOB:
        nKey = sqlite3_value_bytes(argv[2]);
        zKey = (char *)sqlite3_value_blob(argv[2]);
................................................................................
      sqlite3BtreeClose(db->aDb[iDb].pBt);
      db->aDb[iDb].pBt = 0;
      db->aDb[iDb].pSchema = 0;
    }
    sqlite3ResetInternalSchema(db, 0);
    db->nDb = iDb;
    if( rc==SQLITE_NOMEM ){
      db->mallocFailed = 1;
      sqlite3_snprintf(sizeof(zErr),zErr, "out of memory");
    }else{
      sqlite3_snprintf(sizeof(zErr),zErr, "unable to open database: %s", zFile);
    }
    goto attach_error;
  }
  
  return;

attach_error:
  /* Return an error if we get here */
  if( zErrDyn ){
    sqlite3_result_error(context, zErrDyn, -1);
    sqlite3_free(zErrDyn);
  }else{
    zErr[sizeof(zErr)-1] = 0;
    sqlite3_result_error(context, zErr, -1);
  }
}

/*
................................................................................
  int rc;
  NameContext sName;
  Vdbe *v;
  FuncDef *pFunc;
  sqlite3* db = pParse->db;

#ifndef SQLITE_OMIT_AUTHORIZATION
  assert( db->mallocFailed || pAuthArg );
  if( pAuthArg ){
    char *zAuthArg = sqlite3NameFromToken(db, &pAuthArg->span);
    if( !zAuthArg ){
      goto attach_end;
    }
    rc = sqlite3AuthCheck(pParse, type, zAuthArg, 0, 0);
    sqlite3_free(zAuthArg);
    if(rc!=SQLITE_OK ){
      goto attach_end;
    }
  }
#endif /* SQLITE_OMIT_AUTHORIZATION */

  memset(&sName, 0, sizeof(NameContext));
................................................................................
  }

  v = sqlite3GetVdbe(pParse);
  sqlite3ExprCode(pParse, pFilename);
  sqlite3ExprCode(pParse, pDbname);
  sqlite3ExprCode(pParse, pKey);

  assert( v || db->mallocFailed );
  if( v ){
    sqlite3VdbeAddOp(v, OP_Function, 0, nFunc);
    pFunc = sqlite3FindFunction(db, zFunc, strlen(zFunc), nFunc, SQLITE_UTF8,0);
    sqlite3VdbeChangeP3(v, -1, (char *)pFunc, P3_FUNCDEF);

    /* Code an OP_Expire. For an ATTACH statement, set P1 to true (expire this
    ** statement only). For DETACH, set it to false (expire all existing
................................................................................
  const char *zDb;
  struct SrcList_item *pItem;

  if( pList==0 ) return 0;
  zDb = pFix->zDb;
  for(i=0, pItem=pList->a; i<pList->nSrc; i++, pItem++){
    if( pItem->zDatabase==0 ){
      pItem->zDatabase = sqlite3DbStrDup(pFix->pParse->db, zDb);
    }else if( sqlite3StrICmp(pItem->zDatabase,zDb)!=0 ){
      sqlite3ErrorMsg(pFix->pParse,
         "%s %T cannot reference objects in database %s",
         pFix->zType, pFix->pName, pItem->zDatabase);
      return 1;
    }
#if !defined(SQLITE_OMIT_VIEW) || !defined(SQLITE_OMIT_TRIGGER)

** a legal notice, here is a blessing:
**
**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** $Id: btree.c,v 1.396 2007/08/13 14:56:44 drh Exp $
**
** This file implements a external (disk-based) database using BTrees.
** See the header comment on "btreeInt.h" for additional information.
** Including a description of file format and an overview of operation.
*/
#include "btreeInt.h"

................................................................................
    }
  }

  /* If the above search did not find a BtLock struct associating Btree p
  ** with table iTable, allocate one and link it into the list.
  */
  if( !pLock ){
    pLock = (BtLock *)sqliteMalloc(sizeof(BtLock));
    if( !pLock ){
      return SQLITE_NOMEM;
    }
    pLock->iTable = iTable;
    pLock->pBtree = p;
    pLock->pNext = pBt->pLock;
    pBt->pLock = pLock;
................................................................................
  */
  assert( sqlite3ThreadDataReadOnly()->useSharedData || 0==*ppIter );

  while( *ppIter ){
    BtLock *pLock = *ppIter;
    if( pLock->pBtree==p ){
      *ppIter = pLock->pNext;
      sqliteFree(pLock);
    }else{
      ppIter = &pLock->pNext;
    }
  }
}
#endif /* SQLITE_OMIT_SHARED_CACHE */

................................................................................
static void releasePage(MemPage *pPage);  /* Forward reference */

#ifndef SQLITE_OMIT_INCRBLOB
/*
** Invalidate the overflow page-list cache for cursor pCur, if any.
*/
static void invalidateOverflowCache(BtCursor *pCur){
  sqliteFree(pCur->aOverflow);
  pCur->aOverflow = 0;
}

/*
** Invalidate the overflow page-list cache for all cursors opened
** on the shared btree structure pBt.
*/
................................................................................
  /* If this is an intKey table, then the above call to BtreeKeySize()
  ** stores the integer key in pCur->nKey. In this case this value is
  ** all that is required. Otherwise, if pCur is not open on an intKey
  ** table, then malloc space for and store the pCur->nKey bytes of key 
  ** data.
  */
  if( rc==SQLITE_OK && 0==pCur->pPage->intKey){
    void *pKey = sqliteMalloc(pCur->nKey);
    if( pKey ){
      rc = sqlite3BtreeKey(pCur, 0, pCur->nKey, pKey);
      if( rc==SQLITE_OK ){
        pCur->pKey = pKey;
      }else{
        sqliteFree(pKey);
      }
    }else{
      rc = SQLITE_NOMEM;
    }
  }
  assert( !pCur->pPage->intKey || !pCur->pKey );

................................................................................
  return SQLITE_OK;
}

/*
** Clear the current cursor position.
*/
static void clearCursorPosition(BtCursor *pCur){
  sqliteFree(pCur->pKey);
  pCur->pKey = 0;
  pCur->eState = CURSOR_INVALID;
}

/*
** Restore the cursor to the position it was in (or as close to as possible)
** when saveCursorPosition() was called. Note that this call deletes the 
................................................................................
  if( pCur->isIncrblobHandle ){
    return SQLITE_ABORT;
  }
#endif
  pCur->eState = CURSOR_INVALID;
  rc = sqlite3BtreeMoveto(pCur, pCur->pKey, pCur->nKey, 0, &pCur->skip);
  if( rc==SQLITE_OK ){
    sqliteFree(pCur->pKey);
    pCur->pKey = 0;
    assert( pCur->eState==CURSOR_VALID || pCur->eState==CURSOR_INVALID );
  }
  return rc;
}

#define restoreOrClearCursorPosition(p) \
................................................................................
  unsigned char *data;       /* The page data */
  unsigned char *temp;       /* Temp area for cell content */

  assert( sqlite3PagerIswriteable(pPage->pDbPage) );
  assert( pPage->pBt!=0 );
  assert( pPage->pBt->usableSize <= SQLITE_MAX_PAGE_SIZE );
  assert( pPage->nOverflow==0 );
  temp = sqliteMalloc( pPage->pBt->pageSize );
  if( temp==0 ) return SQLITE_NOMEM;
  data = pPage->aData;
  hdr = pPage->hdrOffset;
  cellOffset = pPage->cellOffset;
  nCell = pPage->nCell;
  assert( nCell==get2byte(&data[hdr+3]) );
  usableSize = pPage->pBt->usableSize;
................................................................................
  assert( brk>=cellOffset+2*nCell );
  put2byte(&data[hdr+5], brk);
  data[hdr+1] = 0;
  data[hdr+2] = 0;
  data[hdr+7] = 0;
  addr = cellOffset+2*nCell;
  memset(&data[addr], 0, brk-addr);
  sqliteFree(temp);
  return SQLITE_OK;
}

/*
** Allocate nByte bytes of space on a page.
**
** Return the index into pPage->aData[] of the first byte of
................................................................................
  #ifdef SQLITE_OMIT_MEMORYDB
    const int isMemdb = 0;
  #else
    const int isMemdb = zFilename && !strcmp(zFilename, ":memory:");
  #endif
#endif

  p = sqliteMalloc(sizeof(Btree));
  if( !p ){
    return SQLITE_NOMEM;
  }
  p->inTrans = TRANS_NONE;
  p->pSqlite = pSqlite;

  /* Try to find an existing Btree structure opened on zFilename. */
#if !defined(SQLITE_OMIT_SHARED_CACHE) && !defined(SQLITE_OMIT_DISKIO)
  pTsdro = sqlite3ThreadDataReadOnly();
  if( pTsdro->useSharedData && zFilename && !isMemdb ){
    char *zFullPathname = sqlite3OsFullPathname(zFilename);
    if( !zFullPathname ){
      sqliteFree(p);
      return SQLITE_NOMEM;
    }
    for(pBt=pTsdro->pBtree; pBt; pBt=pBt->pNext){
      assert( pBt->nRef>0 );
      if( 0==strcmp(zFullPathname, sqlite3PagerFilename(pBt->pPager)) ){
        p->pBt = pBt;
        *ppBtree = p;
        pBt->nRef++;
        sqliteFree(zFullPathname);
        return SQLITE_OK;
      }
    }
    sqliteFree(zFullPathname);
  }
#endif

  /*
  ** The following asserts make sure that structures used by the btree are
  ** the right size.  This is to guard against size changes that result
  ** when compiling on a different architecture.
................................................................................
  */
  assert( sizeof(i64)==8 || sizeof(i64)==4 );
  assert( sizeof(u64)==8 || sizeof(u64)==4 );
  assert( sizeof(u32)==4 );
  assert( sizeof(u16)==2 );
  assert( sizeof(Pgno)==4 );

  pBt = sqliteMalloc( sizeof(*pBt) );
  if( pBt==0 ){
    rc = SQLITE_NOMEM;
    goto btree_open_out;
  }
  rc = sqlite3PagerOpen(&pBt->pPager, zFilename, EXTRA_SIZE, flags);
  if( rc==SQLITE_OK ){
    rc = sqlite3PagerReadFileheader(pBt->pPager,sizeof(zDbHeader),zDbHeader);
................................................................................
  *ppBtree = p;

btree_open_out:
  if( rc!=SQLITE_OK ){
    if( pBt && pBt->pPager ){
      sqlite3PagerClose(pBt->pPager);
    }
    sqliteFree(pBt);
    sqliteFree(p);
    *ppBtree = 0;
  }
  return rc;
}

/*
** Close an open database and invalidate all cursors.
................................................................................
  }

  /* Rollback any active transaction and free the handle structure.
  ** The call to sqlite3BtreeRollback() drops any table-locks held by
  ** this handle.
  */
  sqlite3BtreeRollback(p);
  sqliteFree(p);

#ifndef SQLITE_OMIT_SHARED_CACHE
  /* If there are still other outstanding references to the shared-btree
  ** structure, return now. The remainder of this procedure cleans 
  ** up the shared-btree.
  */
  assert( pBt->nRef>0 );
................................................................................

  /* Close the pager and free the shared-btree structure */
  assert( !pBt->pCursor );
  sqlite3PagerClose(pBt->pPager);
  if( pBt->xFreeSchema && pBt->pSchema ){
    pBt->xFreeSchema(pBt->pSchema);
  }
  sqliteFree(pBt->pSchema);
  sqliteFree(pBt);
  return SQLITE_OK;
}

/*
** Change the busy handler callback function.
*/
int sqlite3BtreeSetBusyHandler(Btree *p, BusyHandler *pHandler){
................................................................................
    if( rc!=SQLITE_OK ){
      return rc;
    }
    if( pBt->readOnly && wrFlag ){
      return SQLITE_READONLY;
    }
  }
  pCur = sqliteMalloc( sizeof(*pCur) );
  if( pCur==0 ){
    rc = SQLITE_NOMEM;
    goto create_cursor_exception;
  }
  pCur->pgnoRoot = (Pgno)iTable;
  if( iTable==1 && sqlite3PagerPagecount(pBt->pPager)==0 ){
    rc = SQLITE_EMPTY;
................................................................................
  pCur->eState = CURSOR_INVALID;
  *ppCur = pCur;

  return SQLITE_OK;
create_cursor_exception:
  if( pCur ){
    releasePage(pCur->pPage);
    sqliteFree(pCur);
  }
  unlockBtreeIfUnused(pBt);
  return rc;
}

/*
** Close a cursor.  The read lock on the database file is released
................................................................................
  }
  if( pCur->pNext ){
    pCur->pNext->pPrev = pCur->pPrev;
  }
  releasePage(pCur->pPage);
  unlockBtreeIfUnused(pBt);
  invalidateOverflowCache(pCur);
  sqliteFree(pCur);
  return SQLITE_OK;
}

/*
** Make a temporary cursor by filling in the fields of pTempCur.
** The temporary cursor is not on the cursor list for the Btree.
*/
................................................................................
    ** one entry for each overflow page in the overflow chain. The
    ** page number of the first overflow page is stored in aOverflow[0],
    ** etc. A value of 0 in the aOverflow[] array means "not yet known"
    ** (the cache is lazily populated).
    */
    if( pCur->isIncrblobHandle && !pCur->aOverflow ){
      int nOvfl = (pCur->info.nPayload-pCur->info.nLocal+ovflSize-1)/ovflSize;
      pCur->aOverflow = (Pgno *)sqliteMalloc(sizeof(Pgno)*nOvfl);
      if( nOvfl && !pCur->aOverflow ){
        rc = SQLITE_NOMEM;
      }
    }

    /* If the overflow page-list cache has been allocated and the
    ** entry for the first required overflow page is valid, skip
................................................................................
      }else{
        int available;
        pCellKey = (void *)fetchPayload(pCur, &available, 0);
        nCellKey = pCur->info.nKey;
        if( available>=nCellKey ){
          c = pCur->xCompare(pCur->pArg, nCellKey, pCellKey, nKey, pKey);
        }else{
          pCellKey = sqliteMallocRaw( nCellKey );
          if( pCellKey==0 ) return SQLITE_NOMEM;
          rc = sqlite3BtreeKey(pCur, 0, nCellKey, (void *)pCellKey);
          c = pCur->xCompare(pCur->pArg, nCellKey, pCellKey, nKey, pKey);
          sqliteFree(pCellKey);
          if( rc ) return rc;
        }
      }
      if( c==0 ){
        if( pPage->leafData && !pPage->leaf ){
          lwr = pCur->idx;
          upr = lwr - 1;
................................................................................
  /* Make nMaxCells a multiple of 2 in order to preserve 8-byte
  ** alignment */
  nMaxCells = (nMaxCells + 1)&~1;

  /*
  ** Allocate space for memory structures
  */
  apCell = sqliteMallocRaw( 
       nMaxCells*sizeof(u8*)                           /* apCell */
     + nMaxCells*sizeof(int)                           /* szCell */
     + ROUND8(sizeof(MemPage))*NB                      /* aCopy */
     + pBt->pageSize*(5+NB)                            /* aSpace */
     + (ISAUTOVACUUM ? nMaxCells : 0)                  /* aFrom */
  );
  if( apCell==0 ){
................................................................................
  assert( pParent->isInit );
  rc = balance(pParent, 0);
  
  /*
  ** Cleanup before returning.
  */
balance_cleanup:
  sqliteFree(apCell);
  for(i=0; i<nOld; i++){
    releasePage(apOld[i]);
  }
  for(i=0; i<nNew; i++){
    releasePage(apNew[i]);
  }
  releasePage(pParent);
................................................................................
  u8 **apCell;                 /* All cells from pages being balanced */
  int *szCell;                 /* Local size of all cells */

  assert( pPage->pParent==0 );
  assert( pPage->nCell==0 );
  pBt = pPage->pBt;
  mxCellPerPage = MX_CELL(pBt);
  apCell = sqliteMallocRaw( mxCellPerPage*(sizeof(u8*)+sizeof(int)) );
  if( apCell==0 ) return SQLITE_NOMEM;
  szCell = (int*)&apCell[mxCellPerPage];
  if( pPage->leaf ){
    /* The table is completely empty */
    TRACE(("BALANCE: empty table %d\n", pPage->pgno));
  }else{
    /* The root page is empty but has one child.  Transfer the
................................................................................
        }
      }
    }
#endif
    releasePage(pChild);
  }
end_shallow_balance:
  sqliteFree(apCell);
  return rc;
}


/*
** The root page is overfull
**
................................................................................
  assert( pPage->leaf || !pPage->leafData );
  TRACE(("INSERT: table=%d nkey=%lld ndata=%d page=%d %s\n",
          pCur->pgnoRoot, nKey, nData, pPage->pgno,
          loc==0 ? "overwrite" : "new entry"));
  assert( pPage->isInit );
  rc = sqlite3PagerWrite(pPage->pDbPage);
  if( rc ) return rc;
  newCell = sqliteMallocRaw( MX_CELL_SIZE(pBt) );
  if( newCell==0 ) return SQLITE_NOMEM;
  rc = fillInCell(pPage, newCell, pKey, nKey, pData, nData, nZero, &szNew);
  if( rc ) goto end_insert;
  assert( szNew==cellSizePtr(pPage, newCell) );
  assert( szNew<=MX_CELL_SIZE(pBt) );
  if( loc==0 && CURSOR_VALID==pCur->eState ){
    int szOld;
................................................................................
  rc = balance(pPage, 1);
  /* sqlite3BtreePageDump(pCur->pBt, pCur->pgnoRoot, 1); */
  /* fflush(stdout); */
  if( rc==SQLITE_OK ){
    moveToRoot(pCur);
  }
end_insert:
  sqliteFree(newCell);
  return rc;
}

/*
** Delete the entry that the cursor is pointing to.  The cursor
** is left pointing at a random location.
*/
................................................................................
    if( rc==SQLITE_OK ){
      TRACE(("DELETE: table=%d delete internal from %d replace from leaf %d\n",
         pCur->pgnoRoot, pPage->pgno, leafCur.pPage->pgno));
      dropCell(pPage, pCur->idx, cellSizePtr(pPage, pCell));
      pNext = findCell(leafCur.pPage, leafCur.idx);
      szNext = cellSizePtr(leafCur.pPage, pNext);
      assert( MX_CELL_SIZE(pBt)>=szNext+4 );
      tempCell = sqliteMallocRaw( MX_CELL_SIZE(pBt) );
      if( tempCell==0 ){
        rc = SQLITE_NOMEM;
      }
    }
    if( rc==SQLITE_OK ){
      rc = insertCell(pPage, pCur->idx, pNext-4, szNext+4, tempCell, 0);
    }
................................................................................
      put4byte(findOverflowCell(pPage, pCur->idx), pgnoChild);
      rc = balance(pPage, 0);
    }
    if( rc==SQLITE_OK ){
      dropCell(leafCur.pPage, leafCur.idx, szNext);
      rc = balance(leafCur.pPage, 0);
    }
    sqliteFree(tempCell);
    sqlite3BtreeReleaseTempCursor(&leafCur);
  }else{
    TRACE(("DELETE: table=%d delete from leaf %d\n",
       pCur->pgnoRoot, pPage->pgno));
    dropCell(pPage, pCur->idx, cellSizePtr(pPage, pCell));
    rc = balance(pPage, 0);
  }
................................................................................
  zMsg2 = sqlite3VMPrintf(zFormat, ap);
  va_end(ap);
  if( zMsg1==0 ) zMsg1 = "";
  if( pCheck->zErrMsg ){
    char *zOld = pCheck->zErrMsg;
    pCheck->zErrMsg = 0;
    sqlite3SetString(&pCheck->zErrMsg, zOld, "\n", zMsg1, zMsg2, (char*)0);
    sqliteFree(zOld);
  }else{
    sqlite3SetString(&pCheck->zErrMsg, zMsg1, zMsg2, (char*)0);
  }
  sqliteFree(zMsg2);
}
#endif /* SQLITE_OMIT_INTEGRITY_CHECK */

#ifndef SQLITE_OMIT_INTEGRITY_CHECK
/*
** Add 1 to the reference count for page iPage.  If this is the second
** reference to the page, add an error message to pCheck->zErrMsg.
................................................................................
    checkTreePage(pCheck, pgno, pPage, zContext);
  }
 
  /* Check for complete coverage of the page
  */
  data = pPage->aData;
  hdr = pPage->hdrOffset;
  hit = sqliteMalloc( usableSize );
  if( hit ){
    memset(hit, 1, get2byte(&data[hdr+5]));
    nCell = get2byte(&data[hdr+3]);
    cellStart = hdr + 12 - 4*pPage->leaf;
    for(i=0; i<nCell; i++){
      int pc = get2byte(&data[cellStart+i*2]);
      int size = cellSizePtr(pPage, &data[pc]);
................................................................................
    }
    if( cnt!=data[hdr+7] ){
      checkAppendMsg(pCheck, 0, 
          "Fragmented space is %d byte reported as %d on page %d",
          cnt, data[hdr+7], iPage);
    }
  }
  sqliteFree(hit);

  releasePage(pPage);
  return depth+1;
}
#endif /* SQLITE_OMIT_INTEGRITY_CHECK */

#ifndef SQLITE_OMIT_INTEGRITY_CHECK
................................................................................
  int i;
  int nRef;
  IntegrityCk sCheck;
  BtShared *pBt = p->pBt;

  nRef = sqlite3PagerRefcount(pBt->pPager);
  if( lockBtreeWithRetry(p)!=SQLITE_OK ){
    return sqliteStrDup("Unable to acquire a read lock on the database");
  }
  sCheck.pBt = pBt;
  sCheck.pPager = pBt->pPager;
  sCheck.nPage = sqlite3PagerPagecount(sCheck.pPager);
  sCheck.mxErr = mxErr;
  sCheck.nErr = 0;
  *pnErr = 0;
................................................................................
    sCheck.nPage = pBt->nTrunc;
  }
#endif
  if( sCheck.nPage==0 ){
    unlockBtreeIfUnused(pBt);
    return 0;
  }
  sCheck.anRef = sqliteMallocRaw( (sCheck.nPage+1)*sizeof(sCheck.anRef[0]) );
  if( !sCheck.anRef ){
    unlockBtreeIfUnused(pBt);
    *pnErr = 1;
    return sqlite3MPrintf("Unable to malloc %d bytes", 
        (sCheck.nPage+1)*sizeof(sCheck.anRef[0]));
  }
  for(i=0; i<=sCheck.nPage; i++){ sCheck.anRef[i] = 0; }
................................................................................
      "Outstanding page count goes from %d to %d during this analysis",
      nRef, sqlite3PagerRefcount(pBt->pPager)
    );
  }

  /* Clean  up and report errors.
  */
  sqliteFree(sCheck.anRef);
  *pnErr = sCheck.nErr;
  return sCheck.zErrMsg;
}
#endif /* SQLITE_OMIT_INTEGRITY_CHECK */

/*
** Return the full pathname of the underlying database file.
................................................................................
** The first time this is called on a shared-btree, nBytes bytes of memory
** are allocated, zeroed, and returned to the caller. For each subsequent 
** call the nBytes parameter is ignored and a pointer to the same blob
** of memory returned. 
**
** Just before the shared-btree is closed, the function passed as the 
** xFree argument when the memory allocation was made is invoked on the 
** blob of allocated memory. This function should not call sqliteFree()
** on the memory, the btree layer does that.
*/
void *sqlite3BtreeSchema(Btree *p, int nBytes, void(*xFree)(void *)){
  BtShared *pBt = p->pBt;
  if( !pBt->pSchema ){
    pBt->pSchema = sqliteMalloc(nBytes);
    pBt->xFreeSchema = xFree;
  }
  return pBt->pSchema;
}

/*
** Return true if another user of the same shared btree as the argument

** a legal notice, here is a blessing:
**
**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** $Id: btree.c,v 1.397 2007/08/16 04:30:39 drh Exp $
**
** This file implements a external (disk-based) database using BTrees.
** See the header comment on "btreeInt.h" for additional information.
** Including a description of file format and an overview of operation.
*/
#include "btreeInt.h"

................................................................................
    }
  }

  /* If the above search did not find a BtLock struct associating Btree p
  ** with table iTable, allocate one and link it into the list.
  */
  if( !pLock ){
    pLock = (BtLock *)sqlite3MallocZero(sizeof(BtLock));
    if( !pLock ){
      return SQLITE_NOMEM;
    }
    pLock->iTable = iTable;
    pLock->pBtree = p;
    pLock->pNext = pBt->pLock;
    pBt->pLock = pLock;
................................................................................
  */
  assert( sqlite3ThreadDataReadOnly()->useSharedData || 0==*ppIter );

  while( *ppIter ){
    BtLock *pLock = *ppIter;
    if( pLock->pBtree==p ){
      *ppIter = pLock->pNext;
      sqlite3_free(pLock);
    }else{
      ppIter = &pLock->pNext;
    }
  }
}
#endif /* SQLITE_OMIT_SHARED_CACHE */

................................................................................
static void releasePage(MemPage *pPage);  /* Forward reference */

#ifndef SQLITE_OMIT_INCRBLOB
/*
** Invalidate the overflow page-list cache for cursor pCur, if any.
*/
static void invalidateOverflowCache(BtCursor *pCur){
  sqlite3_free(pCur->aOverflow);
  pCur->aOverflow = 0;
}

/*
** Invalidate the overflow page-list cache for all cursors opened
** on the shared btree structure pBt.
*/
................................................................................
  /* If this is an intKey table, then the above call to BtreeKeySize()
  ** stores the integer key in pCur->nKey. In this case this value is
  ** all that is required. Otherwise, if pCur is not open on an intKey
  ** table, then malloc space for and store the pCur->nKey bytes of key 
  ** data.
  */
  if( rc==SQLITE_OK && 0==pCur->pPage->intKey){
    void *pKey = sqlite3_malloc(pCur->nKey);
    if( pKey ){
      rc = sqlite3BtreeKey(pCur, 0, pCur->nKey, pKey);
      if( rc==SQLITE_OK ){
        pCur->pKey = pKey;
      }else{
        sqlite3_free(pKey);
      }
    }else{
      rc = SQLITE_NOMEM;
    }
  }
  assert( !pCur->pPage->intKey || !pCur->pKey );

................................................................................
  return SQLITE_OK;
}

/*
** Clear the current cursor position.
*/
static void clearCursorPosition(BtCursor *pCur){
  sqlite3_free(pCur->pKey);
  pCur->pKey = 0;
  pCur->eState = CURSOR_INVALID;
}

/*
** Restore the cursor to the position it was in (or as close to as possible)
** when saveCursorPosition() was called. Note that this call deletes the 
................................................................................
  if( pCur->isIncrblobHandle ){
    return SQLITE_ABORT;
  }
#endif
  pCur->eState = CURSOR_INVALID;
  rc = sqlite3BtreeMoveto(pCur, pCur->pKey, pCur->nKey, 0, &pCur->skip);
  if( rc==SQLITE_OK ){
    sqlite3_free(pCur->pKey);
    pCur->pKey = 0;
    assert( pCur->eState==CURSOR_VALID || pCur->eState==CURSOR_INVALID );
  }
  return rc;
}

#define restoreOrClearCursorPosition(p) \
................................................................................
  unsigned char *data;       /* The page data */
  unsigned char *temp;       /* Temp area for cell content */

  assert( sqlite3PagerIswriteable(pPage->pDbPage) );
  assert( pPage->pBt!=0 );
  assert( pPage->pBt->usableSize <= SQLITE_MAX_PAGE_SIZE );
  assert( pPage->nOverflow==0 );
  temp = sqlite3_malloc( pPage->pBt->pageSize );
  if( temp==0 ) return SQLITE_NOMEM;
  data = pPage->aData;
  hdr = pPage->hdrOffset;
  cellOffset = pPage->cellOffset;
  nCell = pPage->nCell;
  assert( nCell==get2byte(&data[hdr+3]) );
  usableSize = pPage->pBt->usableSize;
................................................................................
  assert( brk>=cellOffset+2*nCell );
  put2byte(&data[hdr+5], brk);
  data[hdr+1] = 0;
  data[hdr+2] = 0;
  data[hdr+7] = 0;
  addr = cellOffset+2*nCell;
  memset(&data[addr], 0, brk-addr);
  sqlite3_free(temp);
  return SQLITE_OK;
}

/*
** Allocate nByte bytes of space on a page.
**
** Return the index into pPage->aData[] of the first byte of
................................................................................
  #ifdef SQLITE_OMIT_MEMORYDB
    const int isMemdb = 0;
  #else
    const int isMemdb = zFilename && !strcmp(zFilename, ":memory:");
  #endif
#endif

  p = sqlite3MallocZero(sizeof(Btree));
  if( !p ){
    return SQLITE_NOMEM;
  }
  p->inTrans = TRANS_NONE;
  p->pSqlite = pSqlite;

  /* Try to find an existing Btree structure opened on zFilename. */
#if !defined(SQLITE_OMIT_SHARED_CACHE) && !defined(SQLITE_OMIT_DISKIO)
  pTsdro = sqlite3ThreadDataReadOnly();
  if( pTsdro->useSharedData && zFilename && !isMemdb ){
    char *zFullPathname = sqlite3OsFullPathname(zFilename);
    if( !zFullPathname ){
      sqlite3_free(p);
      return SQLITE_NOMEM;
    }
    for(pBt=pTsdro->pBtree; pBt; pBt=pBt->pNext){
      assert( pBt->nRef>0 );
      if( 0==strcmp(zFullPathname, sqlite3PagerFilename(pBt->pPager)) ){
        p->pBt = pBt;
        *ppBtree = p;
        pBt->nRef++;
        sqlite3_free(zFullPathname);
        return SQLITE_OK;
      }
    }
    sqlite3_free(zFullPathname);
  }
#endif

  /*
  ** The following asserts make sure that structures used by the btree are
  ** the right size.  This is to guard against size changes that result
  ** when compiling on a different architecture.
................................................................................
  */
  assert( sizeof(i64)==8 || sizeof(i64)==4 );
  assert( sizeof(u64)==8 || sizeof(u64)==4 );
  assert( sizeof(u32)==4 );
  assert( sizeof(u16)==2 );
  assert( sizeof(Pgno)==4 );

  pBt = sqlite3MallocZero( sizeof(*pBt) );
  if( pBt==0 ){
    rc = SQLITE_NOMEM;
    goto btree_open_out;
  }
  rc = sqlite3PagerOpen(&pBt->pPager, zFilename, EXTRA_SIZE, flags);
  if( rc==SQLITE_OK ){
    rc = sqlite3PagerReadFileheader(pBt->pPager,sizeof(zDbHeader),zDbHeader);
................................................................................
  *ppBtree = p;

btree_open_out:
  if( rc!=SQLITE_OK ){
    if( pBt && pBt->pPager ){
      sqlite3PagerClose(pBt->pPager);
    }
    sqlite3_free(pBt);
    sqlite3_free(p);
    *ppBtree = 0;
  }
  return rc;
}

/*
** Close an open database and invalidate all cursors.
................................................................................
  }

  /* Rollback any active transaction and free the handle structure.
  ** The call to sqlite3BtreeRollback() drops any table-locks held by
  ** this handle.
  */
  sqlite3BtreeRollback(p);
  sqlite3_free(p);

#ifndef SQLITE_OMIT_SHARED_CACHE
  /* If there are still other outstanding references to the shared-btree
  ** structure, return now. The remainder of this procedure cleans 
  ** up the shared-btree.
  */
  assert( pBt->nRef>0 );
................................................................................

  /* Close the pager and free the shared-btree structure */
  assert( !pBt->pCursor );
  sqlite3PagerClose(pBt->pPager);
  if( pBt->xFreeSchema && pBt->pSchema ){
    pBt->xFreeSchema(pBt->pSchema);
  }
  sqlite3_free(pBt->pSchema);
  sqlite3_free(pBt);
  return SQLITE_OK;
}

/*
** Change the busy handler callback function.
*/
int sqlite3BtreeSetBusyHandler(Btree *p, BusyHandler *pHandler){
................................................................................
    if( rc!=SQLITE_OK ){
      return rc;
    }
    if( pBt->readOnly && wrFlag ){
      return SQLITE_READONLY;
    }
  }
  pCur = sqlite3MallocZero( sizeof(*pCur) );
  if( pCur==0 ){
    rc = SQLITE_NOMEM;
    goto create_cursor_exception;
  }
  pCur->pgnoRoot = (Pgno)iTable;
  if( iTable==1 && sqlite3PagerPagecount(pBt->pPager)==0 ){
    rc = SQLITE_EMPTY;
................................................................................
  pCur->eState = CURSOR_INVALID;
  *ppCur = pCur;

  return SQLITE_OK;
create_cursor_exception:
  if( pCur ){
    releasePage(pCur->pPage);
    sqlite3_free(pCur);
  }
  unlockBtreeIfUnused(pBt);
  return rc;
}

/*
** Close a cursor.  The read lock on the database file is released
................................................................................
  }
  if( pCur->pNext ){
    pCur->pNext->pPrev = pCur->pPrev;
  }
  releasePage(pCur->pPage);
  unlockBtreeIfUnused(pBt);
  invalidateOverflowCache(pCur);
  sqlite3_free(pCur);
  return SQLITE_OK;
}

/*
** Make a temporary cursor by filling in the fields of pTempCur.
** The temporary cursor is not on the cursor list for the Btree.
*/
................................................................................
    ** one entry for each overflow page in the overflow chain. The
    ** page number of the first overflow page is stored in aOverflow[0],
    ** etc. A value of 0 in the aOverflow[] array means "not yet known"
    ** (the cache is lazily populated).
    */
    if( pCur->isIncrblobHandle && !pCur->aOverflow ){
      int nOvfl = (pCur->info.nPayload-pCur->info.nLocal+ovflSize-1)/ovflSize;
      pCur->aOverflow = (Pgno *)sqlite3MallocZero(sizeof(Pgno)*nOvfl);
      if( nOvfl && !pCur->aOverflow ){
        rc = SQLITE_NOMEM;
      }
    }

    /* If the overflow page-list cache has been allocated and the
    ** entry for the first required overflow page is valid, skip
................................................................................
      }else{
        int available;
        pCellKey = (void *)fetchPayload(pCur, &available, 0);
        nCellKey = pCur->info.nKey;
        if( available>=nCellKey ){
          c = pCur->xCompare(pCur->pArg, nCellKey, pCellKey, nKey, pKey);
        }else{
          pCellKey = sqlite3_malloc( nCellKey );
          if( pCellKey==0 ) return SQLITE_NOMEM;
          rc = sqlite3BtreeKey(pCur, 0, nCellKey, (void *)pCellKey);
          c = pCur->xCompare(pCur->pArg, nCellKey, pCellKey, nKey, pKey);
          sqlite3_free(pCellKey);
          if( rc ) return rc;
        }
      }
      if( c==0 ){
        if( pPage->leafData && !pPage->leaf ){
          lwr = pCur->idx;
          upr = lwr - 1;
................................................................................
  /* Make nMaxCells a multiple of 2 in order to preserve 8-byte
  ** alignment */
  nMaxCells = (nMaxCells + 1)&~1;

  /*
  ** Allocate space for memory structures
  */
  apCell = sqlite3_malloc( 
       nMaxCells*sizeof(u8*)                           /* apCell */
     + nMaxCells*sizeof(int)                           /* szCell */
     + ROUND8(sizeof(MemPage))*NB                      /* aCopy */
     + pBt->pageSize*(5+NB)                            /* aSpace */
     + (ISAUTOVACUUM ? nMaxCells : 0)                  /* aFrom */
  );
  if( apCell==0 ){
................................................................................
  assert( pParent->isInit );
  rc = balance(pParent, 0);
  
  /*
  ** Cleanup before returning.
  */
balance_cleanup:
  sqlite3_free(apCell);
  for(i=0; i<nOld; i++){
    releasePage(apOld[i]);
  }
  for(i=0; i<nNew; i++){
    releasePage(apNew[i]);
  }
  releasePage(pParent);
................................................................................
  u8 **apCell;                 /* All cells from pages being balanced */
  int *szCell;                 /* Local size of all cells */

  assert( pPage->pParent==0 );
  assert( pPage->nCell==0 );
  pBt = pPage->pBt;
  mxCellPerPage = MX_CELL(pBt);
  apCell = sqlite3_malloc( mxCellPerPage*(sizeof(u8*)+sizeof(int)) );
  if( apCell==0 ) return SQLITE_NOMEM;
  szCell = (int*)&apCell[mxCellPerPage];
  if( pPage->leaf ){
    /* The table is completely empty */
    TRACE(("BALANCE: empty table %d\n", pPage->pgno));
  }else{
    /* The root page is empty but has one child.  Transfer the
................................................................................
        }
      }
    }
#endif
    releasePage(pChild);
  }
end_shallow_balance:
  sqlite3_free(apCell);
  return rc;
}


/*
** The root page is overfull
**
................................................................................
  assert( pPage->leaf || !pPage->leafData );
  TRACE(("INSERT: table=%d nkey=%lld ndata=%d page=%d %s\n",
          pCur->pgnoRoot, nKey, nData, pPage->pgno,
          loc==0 ? "overwrite" : "new entry"));
  assert( pPage->isInit );
  rc = sqlite3PagerWrite(pPage->pDbPage);
  if( rc ) return rc;
  newCell = sqlite3_malloc( MX_CELL_SIZE(pBt) );
  if( newCell==0 ) return SQLITE_NOMEM;
  rc = fillInCell(pPage, newCell, pKey, nKey, pData, nData, nZero, &szNew);
  if( rc ) goto end_insert;
  assert( szNew==cellSizePtr(pPage, newCell) );
  assert( szNew<=MX_CELL_SIZE(pBt) );
  if( loc==0 && CURSOR_VALID==pCur->eState ){
    int szOld;
................................................................................
  rc = balance(pPage, 1);
  /* sqlite3BtreePageDump(pCur->pBt, pCur->pgnoRoot, 1); */
  /* fflush(stdout); */
  if( rc==SQLITE_OK ){
    moveToRoot(pCur);
  }
end_insert:
  sqlite3_free(newCell);
  return rc;
}

/*
** Delete the entry that the cursor is pointing to.  The cursor
** is left pointing at a random location.
*/
................................................................................
    if( rc==SQLITE_OK ){
      TRACE(("DELETE: table=%d delete internal from %d replace from leaf %d\n",
         pCur->pgnoRoot, pPage->pgno, leafCur.pPage->pgno));
      dropCell(pPage, pCur->idx, cellSizePtr(pPage, pCell));
      pNext = findCell(leafCur.pPage, leafCur.idx);
      szNext = cellSizePtr(leafCur.pPage, pNext);
      assert( MX_CELL_SIZE(pBt)>=szNext+4 );
      tempCell = sqlite3_malloc( MX_CELL_SIZE(pBt) );
      if( tempCell==0 ){
        rc = SQLITE_NOMEM;
      }
    }
    if( rc==SQLITE_OK ){
      rc = insertCell(pPage, pCur->idx, pNext-4, szNext+4, tempCell, 0);
    }
................................................................................
      put4byte(findOverflowCell(pPage, pCur->idx), pgnoChild);
      rc = balance(pPage, 0);
    }
    if( rc==SQLITE_OK ){
      dropCell(leafCur.pPage, leafCur.idx, szNext);
      rc = balance(leafCur.pPage, 0);
    }
    sqlite3_free(tempCell);
    sqlite3BtreeReleaseTempCursor(&leafCur);
  }else{
    TRACE(("DELETE: table=%d delete from leaf %d\n",
       pCur->pgnoRoot, pPage->pgno));
    dropCell(pPage, pCur->idx, cellSizePtr(pPage, pCell));
    rc = balance(pPage, 0);
  }
................................................................................
  zMsg2 = sqlite3VMPrintf(zFormat, ap);
  va_end(ap);
  if( zMsg1==0 ) zMsg1 = "";
  if( pCheck->zErrMsg ){
    char *zOld = pCheck->zErrMsg;
    pCheck->zErrMsg = 0;
    sqlite3SetString(&pCheck->zErrMsg, zOld, "\n", zMsg1, zMsg2, (char*)0);
    sqlite3_free(zOld);
  }else{
    sqlite3SetString(&pCheck->zErrMsg, zMsg1, zMsg2, (char*)0);
  }
  sqlite3_free(zMsg2);
}
#endif /* SQLITE_OMIT_INTEGRITY_CHECK */

#ifndef SQLITE_OMIT_INTEGRITY_CHECK
/*
** Add 1 to the reference count for page iPage.  If this is the second
** reference to the page, add an error message to pCheck->zErrMsg.
................................................................................
    checkTreePage(pCheck, pgno, pPage, zContext);
  }
 
  /* Check for complete coverage of the page
  */
  data = pPage->aData;
  hdr = pPage->hdrOffset;
  hit = sqlite3MallocZero( usableSize );
  if( hit ){
    memset(hit, 1, get2byte(&data[hdr+5]));
    nCell = get2byte(&data[hdr+3]);
    cellStart = hdr + 12 - 4*pPage->leaf;
    for(i=0; i<nCell; i++){
      int pc = get2byte(&data[cellStart+i*2]);
      int size = cellSizePtr(pPage, &data[pc]);
................................................................................
    }
    if( cnt!=data[hdr+7] ){
      checkAppendMsg(pCheck, 0, 
          "Fragmented space is %d byte reported as %d on page %d",
          cnt, data[hdr+7], iPage);
    }
  }
  sqlite3_free(hit);

  releasePage(pPage);
  return depth+1;
}
#endif /* SQLITE_OMIT_INTEGRITY_CHECK */

#ifndef SQLITE_OMIT_INTEGRITY_CHECK
................................................................................
  int i;
  int nRef;
  IntegrityCk sCheck;
  BtShared *pBt = p->pBt;

  nRef = sqlite3PagerRefcount(pBt->pPager);
  if( lockBtreeWithRetry(p)!=SQLITE_OK ){
    return sqlite3StrDup("Unable to acquire a read lock on the database");
  }
  sCheck.pBt = pBt;
  sCheck.pPager = pBt->pPager;
  sCheck.nPage = sqlite3PagerPagecount(sCheck.pPager);
  sCheck.mxErr = mxErr;
  sCheck.nErr = 0;
  *pnErr = 0;
................................................................................
    sCheck.nPage = pBt->nTrunc;
  }
#endif
  if( sCheck.nPage==0 ){
    unlockBtreeIfUnused(pBt);
    return 0;
  }
  sCheck.anRef = sqlite3_malloc( (sCheck.nPage+1)*sizeof(sCheck.anRef[0]) );
  if( !sCheck.anRef ){
    unlockBtreeIfUnused(pBt);
    *pnErr = 1;
    return sqlite3MPrintf("Unable to malloc %d bytes", 
        (sCheck.nPage+1)*sizeof(sCheck.anRef[0]));
  }
  for(i=0; i<=sCheck.nPage; i++){ sCheck.anRef[i] = 0; }
................................................................................
      "Outstanding page count goes from %d to %d during this analysis",
      nRef, sqlite3PagerRefcount(pBt->pPager)
    );
  }

  /* Clean  up and report errors.
  */
  sqlite3_free(sCheck.anRef);
  *pnErr = sCheck.nErr;
  return sCheck.zErrMsg;
}
#endif /* SQLITE_OMIT_INTEGRITY_CHECK */

/*
** Return the full pathname of the underlying database file.
................................................................................
** The first time this is called on a shared-btree, nBytes bytes of memory
** are allocated, zeroed, and returned to the caller. For each subsequent 
** call the nBytes parameter is ignored and a pointer to the same blob
** of memory returned. 
**
** Just before the shared-btree is closed, the function passed as the 
** xFree argument when the memory allocation was made is invoked on the 
** blob of allocated memory. This function should not call sqlite3_free()
** on the memory, the btree layer does that.
*/
void *sqlite3BtreeSchema(Btree *p, int nBytes, void(*xFree)(void *)){
  BtShared *pBt = p->pBt;
  if( !pBt->pSchema ){
    pBt->pSchema = sqlite3MallocZero(nBytes);
    pBt->xFreeSchema = xFree;
  }
  return pBt->pSchema;
}

/*
** Return true if another user of the same shared btree as the argument

**     CREATE INDEX
**     DROP INDEX
**     creating ID lists
**     BEGIN TRANSACTION
**     COMMIT
**     ROLLBACK
**
** $Id: build.c,v 1.433 2007/07/02 19:31:27 drh Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>

/*
** This routine is called when a new SQL statement is beginning to
** be parsed.  Initialize the pParse structure as needed.
................................................................................
    if( p->iDb==iDb && p->iTab==iTab ){
      p->isWriteLock = (p->isWriteLock || isWriteLock);
      return;
    }
  }

  nBytes = sizeof(TableLock) * (pParse->nTableLock+1);
  pParse->aTableLock = sqliteReallocOrFree(pParse->aTableLock, nBytes);

  if( pParse->aTableLock ){
    p = &pParse->aTableLock[pParse->nTableLock++];
    p->iDb = iDb;
    p->iTab = iTab;
    p->isWriteLock = isWriteLock;
    p->zName = zName;
  }
................................................................................
** Note that if an error occurred, it might be the case that
** no VDBE code was generated.
*/
void sqlite3FinishCoding(Parse *pParse){
  sqlite3 *db;
  Vdbe *v;

  if( sqlite3MallocFailed() ) return;

  if( pParse->nested ) return;
  if( !pParse->pVdbe ){
    if( pParse->rc==SQLITE_OK && pParse->nErr ){
      pParse->rc = SQLITE_ERROR;
      return;
    }
  }

  /* Begin by generating some termination code at the end of the
  ** vdbe program
  */
  db = pParse->db;
  v = sqlite3GetVdbe(pParse);
  if( v ){
    sqlite3VdbeAddOp(v, OP_Halt, 0, 0);

    /* The cookie mask contains one bit for each database file open.
    ** (Bit 0 is for main, bit 1 is for temp, and so forth.)  Bits are
    ** set for each database that is used.  Generate code to start a
................................................................................
    sqlite3VdbeOp3(v, OP_Noop, 0, 0, pParse->zSql, pParse->zTail-pParse->zSql);
#endif /* SQLITE_OMIT_TRACE */
  }


  /* Get the VDBE program ready for execution
  */
  if( v && pParse->nErr==0 && !sqlite3MallocFailed() ){
#ifdef SQLITE_DEBUG
    FILE *trace = (db->flags & SQLITE_VdbeTrace)!=0 ? stdout : 0;
    sqlite3VdbeTrace(v, trace);
#endif
    sqlite3VdbeMakeReady(v, pParse->nVar, pParse->nMem+3,
                         pParse->nTab+3, pParse->explain);
    pParse->rc = SQLITE_DONE;
................................................................................

  if( pParse->nErr ) return;
  assert( pParse->nested<10 );  /* Nesting should only be of limited depth */
  va_start(ap, zFormat);
  zSql = sqlite3VMPrintf(zFormat, ap);
  va_end(ap);
  if( zSql==0 ){

    return;   /* A malloc must have failed */
  }
  pParse->nested++;
  memcpy(saveBuf, &pParse->nVar, SAVE_SZ);
  memset(&pParse->nVar, 0, SAVE_SZ);
  sqlite3RunParser(pParse, zSql, 0);
  sqliteFree(zSql);
  memcpy(&pParse->nVar, saveBuf, SAVE_SZ);
  pParse->nested--;
}

/*
** Locate the in-memory structure that describes a particular database
** table given the name of that table and (optionally) the name of the
................................................................................
  return p;
}

/*
** Reclaim the memory used by an index
*/
static void freeIndex(Index *p){
  sqliteFree(p->zColAff);
  sqliteFree(p);
}

/*
** Remove the given index from the index hash table, and free
** its memory structures.
**
** The index is removed from the database hash tables but
................................................................................
      if( pDb->pAux && pDb->xFreeAux ) pDb->xFreeAux(pDb->pAux);
      pDb->pAux = 0;
    }
  }
  for(i=j=2; i<db->nDb; i++){
    struct Db *pDb = &db->aDb[i];
    if( pDb->pBt==0 ){
      sqliteFree(pDb->zName);
      pDb->zName = 0;
      continue;
    }
    if( j<i ){
      db->aDb[j] = db->aDb[i];
    }
    j++;
  }
  memset(&db->aDb[j], 0, (db->nDb-j)*sizeof(db->aDb[j]));
  db->nDb = j;
  if( db->nDb<=2 && db->aDb!=db->aDbStatic ){
    memcpy(db->aDbStatic, db->aDb, 2*sizeof(db->aDb[0]));
    sqliteFree(db->aDb);
    db->aDb = db->aDbStatic;
  }
}

/*
** This routine is called when a commit occurs.
*/
................................................................................
*/
static void sqliteResetColumnNames(Table *pTable){
  int i;
  Column *pCol;
  assert( pTable!=0 );
  if( (pCol = pTable->aCol)!=0 ){
    for(i=0; i<pTable->nCol; i++, pCol++){
      sqliteFree(pCol->zName);
      sqlite3ExprDelete(pCol->pDflt);
      sqliteFree(pCol->zType);
      sqliteFree(pCol->zColl);
    }
    sqliteFree(pTable->aCol);
  }
  pTable->aCol = 0;
  pTable->nCol = 0;
}

/*
** Remove the memory data structures associated with the given
................................................................................
  /* Delete all foreign keys associated with this table.  The keys
  ** should have already been unlinked from the pSchema->aFKey hash table 
  */
  for(pFKey=pTable->pFKey; pFKey; pFKey=pNextFKey){
    pNextFKey = pFKey->pNextFrom;
    assert( sqlite3HashFind(&pTable->pSchema->aFKey,
                           pFKey->zTo, strlen(pFKey->zTo)+1)!=pFKey );
    sqliteFree(pFKey);
  }
#endif

  /* Delete the Table structure itself.
  */
  sqliteResetColumnNames(pTable);
  sqliteFree(pTable->zName);
  sqliteFree(pTable->zColAff);
  sqlite3SelectDelete(pTable->pSelect);
#ifndef SQLITE_OMIT_CHECK
  sqlite3ExprDelete(pTable->pCheck);
#endif
  sqlite3VtabClear(pTable);
  sqliteFree(pTable);
}

/*
** Unlink the given table from the hash tables and the delete the
** table structure with all its indices and foreign keys.
*/
void sqlite3UnlinkAndDeleteTable(sqlite3 *db, int iDb, const char *zTabName){
................................................................................
** is obtained from sqliteMalloc() and must be freed by the calling
** function.
**
** Tokens are often just pointers into the original SQL text and so
** are not \000 terminated and are not persistent.  The returned string
** is \000 terminated and is persistent.
*/
char *sqlite3NameFromToken(Token *pName){
  char *zName;
  if( pName ){
    zName = sqliteStrNDup((char*)pName->z, pName->n);
    sqlite3Dequote(zName);
  }else{
    zName = 0;
  }
  return zName;
}

................................................................................
*/
int sqlite3FindDb(sqlite3 *db, Token *pName){
  int i = -1;    /* Database number */
  int n;         /* Number of characters in the name */
  Db *pDb;       /* A database whose name space is being searched */
  char *zName;   /* Name we are searching for */

  zName = sqlite3NameFromToken(pName);
  if( zName ){
    n = strlen(zName);
    for(i=(db->nDb-1), pDb=&db->aDb[i]; i>=0; i--, pDb--){
      if( (!OMIT_TEMPDB || i!=1 ) && n==strlen(pDb->zName) && 
          0==sqlite3StrICmp(pDb->zName, zName) ){
        break;
      }
    }
    sqliteFree(zName);
  }
  return i;
}

/* The table or view or trigger name is passed to this routine via tokens
** pName1 and pName2. If the table name was fully qualified, for example:
**
................................................................................
    /* If creating a temp table, the name may not be qualified */
    sqlite3ErrorMsg(pParse, "temporary table name must be unqualified");
    return;
  }
  if( !OMIT_TEMPDB && isTemp ) iDb = 1;

  pParse->sNameToken = *pName;
  zName = sqlite3NameFromToken(pName);
  if( zName==0 ) return;
  if( SQLITE_OK!=sqlite3CheckObjectName(pParse, zName) ){
    goto begin_table_error;
  }
  if( db->init.iDb==1 ) isTemp = 1;
#ifndef SQLITE_OMIT_AUTHORIZATION
  assert( (isTemp & 1)==isTemp );
................................................................................
    }
    if( sqlite3FindIndex(db, zName, 0)!=0 && (iDb==0 || !db->init.busy) ){
      sqlite3ErrorMsg(pParse, "there is already an index named %s", zName);
      goto begin_table_error;
    }
  }

  pTable = sqliteMalloc( sizeof(Table) );
  if( pTable==0 ){

    pParse->rc = SQLITE_NOMEM;
    pParse->nErr++;
    goto begin_table_error;
  }
  pTable->zName = zName;
  pTable->iPKey = -1;
  pTable->pSchema = db->aDb[iDb].pSchema;
................................................................................
  }

  /* Normal (non-error) return. */
  return;

  /* If an error occurs, we jump here */
begin_table_error:
  sqliteFree(zName);
  return;
}

/*
** This macro is used to compare two strings in a case-insensitive manner.
** It is slightly faster than calling sqlite3StrICmp() directly, but
** produces larger code.
................................................................................
  char *z;
  Column *pCol;
  if( (p = pParse->pNewTable)==0 ) return;
  if( p->nCol+1>SQLITE_MAX_COLUMN ){
    sqlite3ErrorMsg(pParse, "too many columns on %s", p->zName);
    return;
  }
  z = sqlite3NameFromToken(pName);
  if( z==0 ) return;
  for(i=0; i<p->nCol; i++){
    if( STRICMP(z, p->aCol[i].zName) ){
      sqlite3ErrorMsg(pParse, "duplicate column name: %s", z);
      sqliteFree(z);
      return;
    }
  }
  if( (p->nCol & 0x7)==0 ){
    Column *aNew;
    aNew = sqliteRealloc( p->aCol, (p->nCol+8)*sizeof(p->aCol[0]));
    if( aNew==0 ){

      sqliteFree(z);
      return;
    }
    p->aCol = aNew;
  }
  pCol = &p->aCol[p->nCol];
  memset(pCol, 0, sizeof(p->aCol[0]));
  pCol->zName = z;
................................................................................
  int i;
  Column *pCol;

  if( (p = pParse->pNewTable)==0 ) return;
  i = p->nCol-1;
  if( i<0 ) return;
  pCol = &p->aCol[i];
  sqliteFree(pCol->zType);
  pCol->zType = sqlite3NameFromToken(pType);
  pCol->affinity = sqlite3AffinityType(pType);
}

/*
** The expression is the default value for the most recently added column
** of the table currently under construction.
**
................................................................................
  if( (p = pParse->pNewTable)!=0 ){
    pCol = &(p->aCol[p->nCol-1]);
    if( !sqlite3ExprIsConstantOrFunction(pExpr) ){
      sqlite3ErrorMsg(pParse, "default value of column [%s] is not constant",
          pCol->zName);
    }else{
      Expr *pCopy;

      sqlite3ExprDelete(pCol->pDflt);
      pCol->pDflt = pCopy = sqlite3ExprDup(pExpr);
      if( pCopy ){
        sqlite3TokenCopy(&pCopy->span, &pExpr->span);
      }
    }
  }
  sqlite3ExprDelete(pExpr);
}

/*
................................................................................
*/
void sqlite3AddCheckConstraint(
  Parse *pParse,    /* Parsing context */
  Expr *pCheckExpr  /* The check expression */
){
#ifndef SQLITE_OMIT_CHECK
  Table *pTab = pParse->pNewTable;

  if( pTab && !IN_DECLARE_VTAB ){
    /* The CHECK expression must be duplicated so that tokens refer
    ** to malloced space and not the (ephemeral) text of the CREATE TABLE
    ** statement */
    pTab->pCheck = sqlite3ExprAnd(pTab->pCheck, sqlite3ExprDup(pCheckExpr));

  }
#endif
  sqlite3ExprDelete(pCheckExpr);
}

/*
** Set the collation function of the most recently parsed table column
................................................................................
  int i;

  if( (p = pParse->pNewTable)==0 ) return;
  i = p->nCol-1;

  if( sqlite3LocateCollSeq(pParse, zType, nType) ){
    Index *pIdx;
    p->aCol[i].zColl = sqliteStrNDup(zType, nType);
  
    /* If the column is declared as "<name> PRIMARY KEY COLLATE <type>",
    ** then an index may have been created on this column before the
    ** collation type was added. Correct this if it is the case.
    */
    for(pIdx=p->pIndex; pIdx; pIdx=pIdx->pNext){
      assert( pIdx->nColumn==1 );
................................................................................
    zEnd = ")";
  }else{
    zSep = "\n  ";
    zSep2 = ",\n  ";
    zEnd = "\n)";
  }
  n += 35 + 6*p->nCol;
  zStmt = sqliteMallocRaw( n );
  if( zStmt==0 ) return 0;
  sqlite3_snprintf(n, zStmt,
                  !OMIT_TEMPDB&&isTemp ? "CREATE TEMP TABLE ":"CREATE TABLE ");
  k = strlen(zStmt);
  identPut(zStmt, &k, p->zName);
  zStmt[k++] = '(';
  for(pCol=p->aCol, i=0; i<p->nCol; i++, pCol++){
................................................................................
  Token *pEnd,            /* The final ')' token in the CREATE TABLE */
  Select *pSelect         /* Select from a "CREATE ... AS SELECT" */
){
  Table *p;
  sqlite3 *db = pParse->db;
  int iDb;

  if( (pEnd==0 && pSelect==0) || pParse->nErr || sqlite3MallocFailed() ) {
    return;
  }
  p = pParse->pNewTable;
  if( p==0 ) return;

  assert( !db->init.busy || !pSelect );

................................................................................
       "WHERE rowid=#1",
      db->aDb[iDb].zName, SCHEMA_TABLE(iDb),
      zType,
      p->zName,
      p->zName,
      zStmt
    );
    sqliteFree(zStmt);
    sqlite3ChangeCookie(db, v, iDb);

#ifndef SQLITE_OMIT_AUTOINCREMENT
    /* Check to see if we need to create an sqlite_sequence table for
    ** keeping track of autoincrement keys.
    */
    if( p->autoInc ){
................................................................................
  if( db->init.busy && pParse->nErr==0 ){
    Table *pOld;
    FKey *pFKey; 
    Schema *pSchema = p->pSchema;
    pOld = sqlite3HashInsert(&pSchema->tblHash, p->zName, strlen(p->zName)+1,p);
    if( pOld ){
      assert( p==pOld );  /* Malloc must have failed inside HashInsert() */

      return;
    }
#ifndef SQLITE_OMIT_FOREIGN_KEY
    for(pFKey=p->pFKey; pFKey; pFKey=pFKey->pNextFrom){
      int nTo = strlen(pFKey->zTo) + 1;
      pFKey->pNextTo = sqlite3HashFind(&pSchema->aFKey, pFKey->zTo, nTo);
      sqlite3HashInsert(&pSchema->aFKey, pFKey->zTo, nTo, pFKey);
................................................................................
  Table *p;
  int n;
  const unsigned char *z;
  Token sEnd;
  DbFixer sFix;
  Token *pName;
  int iDb;


  if( pParse->nVar>0 ){
    sqlite3ErrorMsg(pParse, "parameters are not allowed in views");
    sqlite3SelectDelete(pSelect);
    return;
  }
  sqlite3StartTable(pParse, pName1, pName2, isTemp, 1, 0, noErr);
  p = pParse->pNewTable;
  if( p==0 || pParse->nErr ){
    sqlite3SelectDelete(pSelect);
    return;
  }
  sqlite3TwoPartName(pParse, pName1, pName2, &pName);
  iDb = sqlite3SchemaToIndex(pParse->db, p->pSchema);
  if( sqlite3FixInit(&sFix, pParse, iDb, "view", pName)
    && sqlite3FixSelect(&sFix, pSelect)
  ){
    sqlite3SelectDelete(pSelect);
    return;
  }

  /* Make a copy of the entire SELECT statement that defines the view.
  ** This will force all the Expr.token.z values to be dynamically
  ** allocated rather than point to the input string - which means that
  ** they will persist after the current sqlite3_exec() call returns.
  */
  p->pSelect = sqlite3SelectDup(pSelect);
  sqlite3SelectDelete(pSelect);
  if( sqlite3MallocFailed() ){
    return;
  }
  if( !pParse->db->init.busy ){
    sqlite3ViewGetColumnNames(pParse, p);
  }

  /* Locate the end of the CREATE VIEW statement.  Make sEnd point to
  ** the end.
  */
  sEnd = pParse->sLastToken;
................................................................................
** of errors.  If an error is seen leave an error message in pParse->zErrMsg.
*/
int sqlite3ViewGetColumnNames(Parse *pParse, Table *pTable){
  Table *pSelTab;   /* A fake table from which we get the result set */
  Select *pSel;     /* Copy of the SELECT that implements the view */
  int nErr = 0;     /* Number of errors encountered */
  int n;            /* Temporarily holds the number of cursors assigned */


  assert( pTable );

#ifndef SQLITE_OMIT_VIRTUALTABLE
  if( sqlite3VtabCallConnect(pParse, pTable) ){
    return SQLITE_ERROR;
  }
................................................................................
  ** Note that the call to sqlite3ResultSetOfSelect() will expand any
  ** "*" elements in the results set of the view and will assign cursors
  ** to the elements of the FROM clause.  But we do not want these changes
  ** to be permanent.  So the computation is done on a copy of the SELECT
  ** statement that defines the view.
  */
  assert( pTable->pSelect );
  pSel = sqlite3SelectDup(pTable->pSelect);
  if( pSel ){
    n = pParse->nTab;
    sqlite3SrcListAssignCursors(pParse, pSel->pSrc);
    pTable->nCol = -1;
    pSelTab = sqlite3ResultSetOfSelect(pParse, 0, pSel);
    pParse->nTab = n;
    if( pSelTab ){
................................................................................
*/
void sqlite3DropTable(Parse *pParse, SrcList *pName, int isView, int noErr){
  Table *pTab;
  Vdbe *v;
  sqlite3 *db = pParse->db;
  int iDb;

  if( pParse->nErr || sqlite3MallocFailed() ){
    goto exit_drop_table;
  }
  assert( pName->nSrc==1 );
  pTab = sqlite3LocateTable(pParse, pName->a[0].zName, pName->a[0].zDatabase);

  if( pTab==0 ){
    if( noErr ){
................................................................................
  }
  nByte = sizeof(*pFKey) + nCol*sizeof(pFKey->aCol[0]) + pTo->n + 1;
  if( pToCol ){
    for(i=0; i<pToCol->nExpr; i++){
      nByte += strlen(pToCol->a[i].zName) + 1;
    }
  }
  pFKey = sqliteMalloc( nByte );
  if( pFKey==0 ) goto fk_end;


  pFKey->pFrom = p;
  pFKey->pNextFrom = p->pFKey;
  z = (char*)&pFKey[1];
  pFKey->aCol = (struct sColMap*)z;
  z += sizeof(struct sColMap)*nCol;
  pFKey->zTo = z;
  memcpy(z, pTo->z, pTo->n);
................................................................................

  /* Link the foreign key to the table as the last step.
  */
  p->pFKey = pFKey;
  pFKey = 0;

fk_end:
  sqliteFree(pFKey);
#endif /* !defined(SQLITE_OMIT_FOREIGN_KEY) */
  sqlite3ExprListDelete(pFromCol);
  sqlite3ExprListDelete(pToCol);
}

/*
** This routine is called when an INITIALLY IMMEDIATE or INITIALLY DEFERRED
................................................................................
  Table *pTab = pIndex->pTable;  /* The table that is indexed */
  int iTab = pParse->nTab;       /* Btree cursor used for pTab */
  int iIdx = pParse->nTab+1;     /* Btree cursor used for pIndex */
  int addr1;                     /* Address of top of loop */
  int tnum;                      /* Root page of index */
  Vdbe *v;                       /* Generate code into this virtual machine */
  KeyInfo *pKey;                 /* KeyInfo for index */

  int iDb = sqlite3SchemaToIndex(pParse->db, pIndex->pSchema);

#ifndef SQLITE_OMIT_AUTHORIZATION
  if( sqlite3AuthCheck(pParse, SQLITE_REINDEX, pIndex->zName, 0,
      pParse->db->aDb[iDb].zName ) ){
    return;
  }
#endif

  /* Require a write-lock on the table to perform this operation */
  sqlite3TableLock(pParse, iDb, pTab->tnum, 1, pTab->zName);

................................................................................
    int addr2 = curaddr+4;
    sqlite3VdbeChangeP2(v, curaddr-1, addr2);
    sqlite3VdbeAddOp(v, OP_Rowid, iTab, 0);
    sqlite3VdbeAddOp(v, OP_AddImm, 1, 0);
    sqlite3VdbeAddOp(v, OP_IsUnique, iIdx, addr2);
    sqlite3VdbeOp3(v, OP_Halt, SQLITE_CONSTRAINT, OE_Abort,
                    "indexed columns are not unique", P3_STATIC);
    assert( sqlite3MallocFailed() || addr2==sqlite3VdbeCurrentAddr(v) );
  }
  sqlite3VdbeAddOp(v, OP_IdxInsert, iIdx, 0);
  sqlite3VdbeAddOp(v, OP_Next, iTab, addr1+1);
  sqlite3VdbeJumpHere(v, addr1);
  sqlite3VdbeAddOp(v, OP_Close, iTab, 0);
  sqlite3VdbeAddOp(v, OP_Close, iIdx, 0);
}
................................................................................
  int iDb;             /* Index of the database that is being written */
  Token *pName = 0;    /* Unqualified name of the index to create */
  struct ExprList_item *pListItem; /* For looping over pList */
  int nCol;
  int nExtra = 0;
  char *zExtra;

  if( pParse->nErr || sqlite3MallocFailed() || IN_DECLARE_VTAB ){
    goto exit_create_index;
  }

  /*
  ** Find the table that is to be indexed.  Return early if not found.
  */
  if( pTblName!=0 ){
................................................................................
  ** index, then we will continue to process this index.
  **
  ** If pName==0 it means that we are
  ** dealing with a primary key or UNIQUE constraint.  We have to invent our
  ** own name.
  */
  if( pName ){
    zName = sqlite3NameFromToken(pName);
    if( SQLITE_OK!=sqlite3ReadSchema(pParse) ) goto exit_create_index;
    if( zName==0 ) goto exit_create_index;
    if( SQLITE_OK!=sqlite3CheckObjectName(pParse, zName) ){
      goto exit_create_index;
    }
    if( !db->init.busy ){
      if( SQLITE_OK!=sqlite3ReadSchema(pParse) ) goto exit_create_index;
................................................................................
  }

  /* 
  ** Allocate the index structure. 
  */
  nName = strlen(zName);
  nCol = pList->nExpr;
  pIndex = sqliteMalloc( 
      sizeof(Index) +              /* Index structure  */
      sizeof(int)*nCol +           /* Index.aiColumn   */
      sizeof(int)*(nCol+1) +       /* Index.aiRowEst   */
      sizeof(char *)*nCol +        /* Index.azColl     */
      sizeof(u8)*nCol +            /* Index.aSortOrder */
      nName + 1 +                  /* Index.zName      */
      nExtra                       /* Collation sequence names */
  );

  if( sqlite3MallocFailed() ) goto exit_create_index;

  pIndex->azColl = (char**)(&pIndex[1]);
  pIndex->aiColumn = (int *)(&pIndex->azColl[nCol]);
  pIndex->aiRowEst = (unsigned *)(&pIndex->aiColumn[nCol]);
  pIndex->aSortOrder = (u8 *)(&pIndex->aiRowEst[nCol+1]);
  pIndex->zName = (char *)(&pIndex->aSortOrder[nCol]);
  zExtra = (char *)(&pIndex->zName[nName+1]);
  memcpy(pIndex->zName, zName, nName+1);
................................................................................
  */
  if( db->init.busy ){
    Index *p;
    p = sqlite3HashInsert(&pIndex->pSchema->idxHash, 
                         pIndex->zName, strlen(pIndex->zName)+1, pIndex);
    if( p ){
      assert( p==pIndex );  /* Malloc must have failed */

      goto exit_create_index;
    }
    db->flags |= SQLITE_InternChanges;
    if( pTblName!=0 ){
      pIndex->tnum = db->init.newTnum;
    }
  }
................................................................................
        "INSERT INTO %Q.%s VALUES('index',%Q,%Q,#0,%Q);",
        db->aDb[iDb].zName, SCHEMA_TABLE(iDb),
        pIndex->zName,
        pTab->zName,
        zStmt
    );
    sqlite3VdbeAddOp(v, OP_Pop, 1, 0);
    sqliteFree(zStmt);

    /* Fill the index with data and reparse the schema. Code an OP_Expire
    ** to invalidate all pre-compiled statements.
    */
    if( pTblName ){
      sqlite3RefillIndex(pParse, pIndex, iMem);
      sqlite3ChangeCookie(db, v, iDb);
................................................................................
  /* Clean up before exiting */
exit_create_index:
  if( pIndex ){
    freeIndex(pIndex);
  }
  sqlite3ExprListDelete(pList);
  sqlite3SrcListDelete(pTblName);
  sqliteFree(zName);
  return;
}

/*
** Generate code to make sure the file format number is at least minFormat.
** The generated code will increase the file format number if necessary.
*/
................................................................................
*/
void sqlite3DropIndex(Parse *pParse, SrcList *pName, int ifExists){
  Index *pIndex;
  Vdbe *v;
  sqlite3 *db = pParse->db;
  int iDb;

  if( pParse->nErr || sqlite3MallocFailed() ){
    goto exit_drop_index;
  }
  assert( pName->nSrc==1 );
  if( SQLITE_OK!=sqlite3ReadSchema(pParse) ){
    goto exit_drop_index;
  }
  pIndex = sqlite3FindIndex(db, pName->a[0].zName, pName->a[0].zDatabase);
................................................................................
** The index of the new entry is returned in *pIdx.
**
** This routine returns a pointer to the array of objects.  This
** might be the same as the pArray parameter or it might be a different
** pointer if the array was resized.
*/
void *sqlite3ArrayAllocate(

  void *pArray,     /* Array of objects.  Might be reallocated */
  int szEntry,      /* Size of each object in the array */
  int initSize,     /* Suggested initial allocation, in elements */
  int *pnEntry,     /* Number of objects currently in use */
  int *pnAlloc,     /* Current size of the allocation, in elements */
  int *pIdx         /* Write the index of a new slot here */
){
  char *z;
  if( *pnEntry >= *pnAlloc ){
    void *pNew;
    int newSize;
    newSize = (*pnAlloc)*2 + initSize;
    pNew = sqliteRealloc(pArray, newSize*szEntry);
    if( pNew==0 ){

      *pIdx = -1;
      return pArray;
    }
    *pnAlloc = newSize;
    pArray = pNew;
  }
  z = (char*)pArray;
................................................................................

/*
** Append a new element to the given IdList.  Create a new IdList if
** need be.
**
** A new IdList is returned, or NULL if malloc() fails.
*/
IdList *sqlite3IdListAppend(IdList *pList, Token *pToken){
  int i;
  if( pList==0 ){
    pList = sqliteMalloc( sizeof(IdList) );
    if( pList==0 ) return 0;
    pList->nAlloc = 0;
  }
  pList->a = sqlite3ArrayAllocate(

      pList->a,
      sizeof(pList->a[0]),
      5,
      &pList->nId,
      &pList->nAlloc,
      &i
  );
  if( i<0 ){
    sqlite3IdListDelete(pList);
    return 0;
  }
  pList->a[i].zName = sqlite3NameFromToken(pToken);
  return pList;
}

/*
** Delete an IdList.
*/
void sqlite3IdListDelete(IdList *pList){
  int i;
  if( pList==0 ) return;
  for(i=0; i<pList->nId; i++){
    sqliteFree(pList->a[i].zName);
  }
  sqliteFree(pList->a);
  sqliteFree(pList);
}

/*
** Return the index in pList of the identifier named zId.  Return -1
** if not found.
*/
int sqlite3IdListIndex(IdList *pList, const char *zName){
................................................................................
** The SrcList.a[].zName field is filled with the table name which might
** come from pTable (if pDatabase is NULL) or from pDatabase.  
** SrcList.a[].zDatabase is filled with the database name from pTable,
** or with NULL if no database is specified.
**
** In other words, if call like this:
**
**         sqlite3SrcListAppend(A,B,0);
**
** Then B is a table name and the database name is unspecified.  If called
** like this:
**
**         sqlite3SrcListAppend(A,B,C);
**
** Then C is the table name and B is the database name.
*/
SrcList *sqlite3SrcListAppend(SrcList *pList, Token *pTable, Token *pDatabase){





  struct SrcList_item *pItem;
  if( pList==0 ){
    pList = sqliteMalloc( sizeof(SrcList) );

    if( pList==0 ) return 0;
    pList->nAlloc = 1;
  }
  if( pList->nSrc>=pList->nAlloc ){
    SrcList *pNew;
    pList->nAlloc *= 2;
    pNew = sqliteRealloc(pList,
               sizeof(*pList) + (pList->nAlloc-1)*sizeof(pList->a[0]) );
    if( pNew==0 ){

      sqlite3SrcListDelete(pList);
      return 0;
    }
    pList = pNew;
  }
  pItem = &pList->a[pList->nSrc];
  memset(pItem, 0, sizeof(pList->a[0]));
................................................................................
    pDatabase = 0;
  }
  if( pDatabase && pTable ){
    Token *pTemp = pDatabase;
    pDatabase = pTable;
    pTable = pTemp;
  }
  pItem->zName = sqlite3NameFromToken(pTable);
  pItem->zDatabase = sqlite3NameFromToken(pDatabase);
  pItem->iCursor = -1;
  pItem->isPopulated = 0;
  pList->nSrc++;
  return pList;
}

/*
** Assign cursors to all tables in a SrcList
*/
void sqlite3SrcListAssignCursors(Parse *pParse, SrcList *pList){
  int i;
  struct SrcList_item *pItem;
  assert(pList || sqlite3MallocFailed() );
  if( pList ){
    for(i=0, pItem=pList->a; i<pList->nSrc; i++, pItem++){
      if( pItem->iCursor>=0 ) break;
      pItem->iCursor = pParse->nTab++;
      if( pItem->pSelect ){
        sqlite3SrcListAssignCursors(pParse, pItem->pSelect->pSrc);
      }
................................................................................
** Delete an entire SrcList including all its substructure.
*/
void sqlite3SrcListDelete(SrcList *pList){
  int i;
  struct SrcList_item *pItem;
  if( pList==0 ) return;
  for(pItem=pList->a, i=0; i<pList->nSrc; i++, pItem++){
    sqliteFree(pItem->zDatabase);
    sqliteFree(pItem->zName);
    sqliteFree(pItem->zAlias);
    sqlite3DeleteTable(pItem->pTab);
    sqlite3SelectDelete(pItem->pSelect);
    sqlite3ExprDelete(pItem->pOn);
    sqlite3IdListDelete(pItem->pUsing);
  }
  sqliteFree(pList);
}

/*
** This routine is called by the parser to add a new term to the
** end of a growing FROM clause.  The "p" parameter is the part of
** the FROM clause that has already been constructed.  "p" is NULL
** if this is the first term of the FROM clause.  pTable and pDatabase
................................................................................
** pDatabase parameters are NULL for subqueries.  The pOn and pUsing
** parameters are the content of the ON and USING clauses.
**
** Return a new SrcList which encodes is the FROM with the new
** term added.
*/
SrcList *sqlite3SrcListAppendFromTerm(

  SrcList *p,             /* The left part of the FROM clause already seen */
  Token *pTable,          /* Name of the table to add to the FROM clause */
  Token *pDatabase,       /* Name of the database containing pTable */
  Token *pAlias,          /* The right-hand side of the AS subexpression */
  Select *pSubquery,      /* A subquery used in place of a table name */
  Expr *pOn,              /* The ON clause of a join */
  IdList *pUsing          /* The USING clause of a join */
){
  struct SrcList_item *pItem;

  p = sqlite3SrcListAppend(p, pTable, pDatabase);
  if( p==0 || p->nSrc==0 ){
    sqlite3ExprDelete(pOn);
    sqlite3IdListDelete(pUsing);
    sqlite3SelectDelete(pSubquery);
    return p;
  }
  pItem = &p->a[p->nSrc-1];
  if( pAlias && pAlias->n ){
    pItem->zAlias = sqlite3NameFromToken(pAlias);
  }
  pItem->pSelect = pSubquery;
  pItem->pOn = pOn;
  pItem->pUsing = pUsing;
  return p;
}

................................................................................
*/
void sqlite3BeginTransaction(Parse *pParse, int type){
  sqlite3 *db;
  Vdbe *v;
  int i;

  if( pParse==0 || (db=pParse->db)==0 || db->aDb[0].pBt==0 ) return;
  if( pParse->nErr || sqlite3MallocFailed() ) return;
  if( sqlite3AuthCheck(pParse, SQLITE_TRANSACTION, "BEGIN", 0, 0) ) return;

  v = sqlite3GetVdbe(pParse);
  if( !v ) return;
  if( type!=TK_DEFERRED ){
    for(i=0; i<db->nDb; i++){
      sqlite3VdbeAddOp(v, OP_Transaction, i, (type==TK_EXCLUSIVE)+1);
................................................................................
** Commit a transaction
*/
void sqlite3CommitTransaction(Parse *pParse){
  sqlite3 *db;
  Vdbe *v;

  if( pParse==0 || (db=pParse->db)==0 || db->aDb[0].pBt==0 ) return;
  if( pParse->nErr || sqlite3MallocFailed() ) return;
  if( sqlite3AuthCheck(pParse, SQLITE_TRANSACTION, "COMMIT", 0, 0) ) return;

  v = sqlite3GetVdbe(pParse);
  if( v ){
    sqlite3VdbeAddOp(v, OP_AutoCommit, 1, 0);
  }
}
................................................................................
** Rollback a transaction
*/
void sqlite3RollbackTransaction(Parse *pParse){
  sqlite3 *db;
  Vdbe *v;

  if( pParse==0 || (db=pParse->db)==0 || db->aDb[0].pBt==0 ) return;
  if( pParse->nErr || sqlite3MallocFailed() ) return;
  if( sqlite3AuthCheck(pParse, SQLITE_TRANSACTION, "ROLLBACK", 0, 0) ) return;

  v = sqlite3GetVdbe(pParse);
  if( v ){
    sqlite3VdbeAddOp(v, OP_AutoCommit, 1, 1);
  }
}
................................................................................
  if( pName1==0 || pName1->z==0 ){
    reindexDatabases(pParse, 0);
    return;
  }else if( pName2==0 || pName2->z==0 ){
    assert( pName1->z );
    pColl = sqlite3FindCollSeq(db, ENC(db), (char*)pName1->z, pName1->n, 0);
    if( pColl ){
      char *zColl = sqliteStrNDup((const char *)pName1->z, pName1->n);
      if( zColl ){
        reindexDatabases(pParse, zColl);
        sqliteFree(zColl);
      }
      return;
    }
  }
  iDb = sqlite3TwoPartName(pParse, pName1, pName2, &pObjName);
  if( iDb<0 ) return;
  z = sqlite3NameFromToken(pObjName);
  if( z==0 ) return;
  zDb = db->aDb[iDb].zName;
  pTab = sqlite3FindTable(db, z, zDb);
  if( pTab ){
    reindexTable(pParse, pTab, 0);
    sqliteFree(z);
    return;
  }
  pIndex = sqlite3FindIndex(db, z, zDb);
  sqliteFree(z);
  if( pIndex ){
    sqlite3BeginWriteOperation(pParse, 0, iDb);
    sqlite3RefillIndex(pParse, pIndex, -1);
    return;
  }
  sqlite3ErrorMsg(pParse, "unable to identify the object to be reindexed");
}
................................................................................
#endif

/*
** Return a dynamicly allocated KeyInfo structure that can be used
** with OP_OpenRead or OP_OpenWrite to access database index pIdx.
**
** If successful, a pointer to the new structure is returned. In this case
** the caller is responsible for calling sqliteFree() on the returned 
** pointer. If an error occurs (out of memory or missing collation 
** sequence), NULL is returned and the state of pParse updated to reflect
** the error.
*/
KeyInfo *sqlite3IndexKeyinfo(Parse *pParse, Index *pIdx){
  int i;
  int nCol = pIdx->nColumn;
  int nBytes = sizeof(KeyInfo) + (nCol-1)*sizeof(CollSeq*) + nCol;
  KeyInfo *pKey = (KeyInfo *)sqliteMalloc(nBytes);

  if( pKey ){
    pKey->aSortOrder = (u8 *)&(pKey->aColl[nCol]);
    assert( &pKey->aSortOrder[nCol]==&(((u8 *)pKey)[nBytes]) );
    for(i=0; i<nCol; i++){
      char *zColl = pIdx->azColl[i];
      assert( zColl );
................................................................................
      pKey->aColl[i] = sqlite3LocateCollSeq(pParse, zColl, -1);
      pKey->aSortOrder[i] = pIdx->aSortOrder[i];
    }
    pKey->nField = nCol;
  }

  if( pParse->nErr ){
    sqliteFree(pKey);
    pKey = 0;
  }
  return pKey;
}

**     CREATE INDEX
**     DROP INDEX
**     creating ID lists
**     BEGIN TRANSACTION
**     COMMIT
**     ROLLBACK
**
** $Id: build.c,v 1.434 2007/08/16 04:30:39 drh Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>

/*
** This routine is called when a new SQL statement is beginning to
** be parsed.  Initialize the pParse structure as needed.
................................................................................
    if( p->iDb==iDb && p->iTab==iTab ){
      p->isWriteLock = (p->isWriteLock || isWriteLock);
      return;
    }
  }

  nBytes = sizeof(TableLock) * (pParse->nTableLock+1);
  pParse->aTableLock = 
      sqlite3DbReallocOrFree(pParse->db, pParse->aTableLock, nBytes);
  if( pParse->aTableLock ){
    p = &pParse->aTableLock[pParse->nTableLock++];
    p->iDb = iDb;
    p->iTab = iTab;
    p->isWriteLock = isWriteLock;
    p->zName = zName;
  }
................................................................................
** Note that if an error occurred, it might be the case that
** no VDBE code was generated.
*/
void sqlite3FinishCoding(Parse *pParse){
  sqlite3 *db;
  Vdbe *v;

  db = pParse->db;
  if( db->mallocFailed ) return;
  if( pParse->nested ) return;
  if( !pParse->pVdbe ){
    if( pParse->rc==SQLITE_OK && pParse->nErr ){
      pParse->rc = SQLITE_ERROR;
      return;
    }
  }

  /* Begin by generating some termination code at the end of the
  ** vdbe program
  */

  v = sqlite3GetVdbe(pParse);
  if( v ){
    sqlite3VdbeAddOp(v, OP_Halt, 0, 0);

    /* The cookie mask contains one bit for each database file open.
    ** (Bit 0 is for main, bit 1 is for temp, and so forth.)  Bits are
    ** set for each database that is used.  Generate code to start a
................................................................................
    sqlite3VdbeOp3(v, OP_Noop, 0, 0, pParse->zSql, pParse->zTail-pParse->zSql);
#endif /* SQLITE_OMIT_TRACE */
  }


  /* Get the VDBE program ready for execution
  */
  if( v && pParse->nErr==0 && !db->mallocFailed ){
#ifdef SQLITE_DEBUG
    FILE *trace = (db->flags & SQLITE_VdbeTrace)!=0 ? stdout : 0;
    sqlite3VdbeTrace(v, trace);
#endif
    sqlite3VdbeMakeReady(v, pParse->nVar, pParse->nMem+3,
                         pParse->nTab+3, pParse->explain);
    pParse->rc = SQLITE_DONE;
................................................................................

  if( pParse->nErr ) return;
  assert( pParse->nested<10 );  /* Nesting should only be of limited depth */
  va_start(ap, zFormat);
  zSql = sqlite3VMPrintf(zFormat, ap);
  va_end(ap);
  if( zSql==0 ){
    pParse->db->mallocFailed = 1;
    return;   /* A malloc must have failed */
  }
  pParse->nested++;
  memcpy(saveBuf, &pParse->nVar, SAVE_SZ);
  memset(&pParse->nVar, 0, SAVE_SZ);
  sqlite3RunParser(pParse, zSql, 0);
  sqlite3_free(zSql);
  memcpy(&pParse->nVar, saveBuf, SAVE_SZ);
  pParse->nested--;
}

/*
** Locate the in-memory structure that describes a particular database
** table given the name of that table and (optionally) the name of the
................................................................................
  return p;
}

/*
** Reclaim the memory used by an index
*/
static void freeIndex(Index *p){
  sqlite3_free(p->zColAff);
  sqlite3_free(p);
}

/*
** Remove the given index from the index hash table, and free
** its memory structures.
**
** The index is removed from the database hash tables but
................................................................................
      if( pDb->pAux && pDb->xFreeAux ) pDb->xFreeAux(pDb->pAux);
      pDb->pAux = 0;
    }
  }
  for(i=j=2; i<db->nDb; i++){
    struct Db *pDb = &db->aDb[i];
    if( pDb->pBt==0 ){
      sqlite3_free(pDb->zName);
      pDb->zName = 0;
      continue;
    }
    if( j<i ){
      db->aDb[j] = db->aDb[i];
    }
    j++;
  }
  memset(&db->aDb[j], 0, (db->nDb-j)*sizeof(db->aDb[j]));
  db->nDb = j;
  if( db->nDb<=2 && db->aDb!=db->aDbStatic ){
    memcpy(db->aDbStatic, db->aDb, 2*sizeof(db->aDb[0]));
    sqlite3_free(db->aDb);
    db->aDb = db->aDbStatic;
  }
}

/*
** This routine is called when a commit occurs.
*/
................................................................................
*/
static void sqliteResetColumnNames(Table *pTable){
  int i;
  Column *pCol;
  assert( pTable!=0 );
  if( (pCol = pTable->aCol)!=0 ){
    for(i=0; i<pTable->nCol; i++, pCol++){
      sqlite3_free(pCol->zName);
      sqlite3ExprDelete(pCol->pDflt);
      sqlite3_free(pCol->zType);
      sqlite3_free(pCol->zColl);
    }
    sqlite3_free(pTable->aCol);
  }
  pTable->aCol = 0;
  pTable->nCol = 0;
}

/*
** Remove the memory data structures associated with the given
................................................................................
  /* Delete all foreign keys associated with this table.  The keys
  ** should have already been unlinked from the pSchema->aFKey hash table 
  */
  for(pFKey=pTable->pFKey; pFKey; pFKey=pNextFKey){
    pNextFKey = pFKey->pNextFrom;
    assert( sqlite3HashFind(&pTable->pSchema->aFKey,
                           pFKey->zTo, strlen(pFKey->zTo)+1)!=pFKey );
    sqlite3_free(pFKey);
  }
#endif

  /* Delete the Table structure itself.
  */
  sqliteResetColumnNames(pTable);
  sqlite3_free(pTable->zName);
  sqlite3_free(pTable->zColAff);
  sqlite3SelectDelete(pTable->pSelect);
#ifndef SQLITE_OMIT_CHECK
  sqlite3ExprDelete(pTable->pCheck);
#endif
  sqlite3VtabClear(pTable);
  sqlite3_free(pTable);
}

/*
** Unlink the given table from the hash tables and the delete the
** table structure with all its indices and foreign keys.
*/
void sqlite3UnlinkAndDeleteTable(sqlite3 *db, int iDb, const char *zTabName){
................................................................................
** is obtained from sqliteMalloc() and must be freed by the calling
** function.
**
** Tokens are often just pointers into the original SQL text and so
** are not \000 terminated and are not persistent.  The returned string
** is \000 terminated and is persistent.
*/
char *sqlite3NameFromToken(sqlite3 *db, Token *pName){
  char *zName;
  if( pName ){
    zName = sqlite3DbStrNDup(db, (char*)pName->z, pName->n);
    sqlite3Dequote(zName);
  }else{
    zName = 0;
  }
  return zName;
}

................................................................................
*/
int sqlite3FindDb(sqlite3 *db, Token *pName){
  int i = -1;    /* Database number */
  int n;         /* Number of characters in the name */
  Db *pDb;       /* A database whose name space is being searched */
  char *zName;   /* Name we are searching for */

  zName = sqlite3NameFromToken(db, pName);
  if( zName ){
    n = strlen(zName);
    for(i=(db->nDb-1), pDb=&db->aDb[i]; i>=0; i--, pDb--){
      if( (!OMIT_TEMPDB || i!=1 ) && n==strlen(pDb->zName) && 
          0==sqlite3StrICmp(pDb->zName, zName) ){
        break;
      }
    }
    sqlite3_free(zName);
  }
  return i;
}

/* The table or view or trigger name is passed to this routine via tokens
** pName1 and pName2. If the table name was fully qualified, for example:
**
................................................................................
    /* If creating a temp table, the name may not be qualified */
    sqlite3ErrorMsg(pParse, "temporary table name must be unqualified");
    return;
  }
  if( !OMIT_TEMPDB && isTemp ) iDb = 1;

  pParse->sNameToken = *pName;
  zName = sqlite3NameFromToken(db, pName);
  if( zName==0 ) return;
  if( SQLITE_OK!=sqlite3CheckObjectName(pParse, zName) ){
    goto begin_table_error;
  }
  if( db->init.iDb==1 ) isTemp = 1;
#ifndef SQLITE_OMIT_AUTHORIZATION
  assert( (isTemp & 1)==isTemp );
................................................................................
    }
    if( sqlite3FindIndex(db, zName, 0)!=0 && (iDb==0 || !db->init.busy) ){
      sqlite3ErrorMsg(pParse, "there is already an index named %s", zName);
      goto begin_table_error;
    }
  }

  pTable = sqlite3MallocZero( sizeof(Table) );
  if( pTable==0 ){
    db->mallocFailed = 1;
    pParse->rc = SQLITE_NOMEM;
    pParse->nErr++;
    goto begin_table_error;
  }
  pTable->zName = zName;
  pTable->iPKey = -1;
  pTable->pSchema = db->aDb[iDb].pSchema;
................................................................................
  }

  /* Normal (non-error) return. */
  return;

  /* If an error occurs, we jump here */
begin_table_error:
  sqlite3_free(zName);
  return;
}

/*
** This macro is used to compare two strings in a case-insensitive manner.
** It is slightly faster than calling sqlite3StrICmp() directly, but
** produces larger code.
................................................................................
  char *z;
  Column *pCol;
  if( (p = pParse->pNewTable)==0 ) return;
  if( p->nCol+1>SQLITE_MAX_COLUMN ){
    sqlite3ErrorMsg(pParse, "too many columns on %s", p->zName);
    return;
  }
  z = sqlite3NameFromToken(pParse->db, pName);
  if( z==0 ) return;
  for(i=0; i<p->nCol; i++){
    if( STRICMP(z, p->aCol[i].zName) ){
      sqlite3ErrorMsg(pParse, "duplicate column name: %s", z);
      sqlite3_free(z);
      return;
    }
  }
  if( (p->nCol & 0x7)==0 ){
    Column *aNew;
    aNew = sqlite3_realloc( p->aCol, (p->nCol+8)*sizeof(p->aCol[0]));
    if( aNew==0 ){
      pParse->db->mallocFailed = 1;
      sqlite3_free(z);
      return;
    }
    p->aCol = aNew;
  }
  pCol = &p->aCol[p->nCol];
  memset(pCol, 0, sizeof(p->aCol[0]));
  pCol->zName = z;
................................................................................
  int i;
  Column *pCol;

  if( (p = pParse->pNewTable)==0 ) return;
  i = p->nCol-1;
  if( i<0 ) return;
  pCol = &p->aCol[i];
  sqlite3_free(pCol->zType);
  pCol->zType = sqlite3NameFromToken(pParse->db, pType);
  pCol->affinity = sqlite3AffinityType(pType);
}

/*
** The expression is the default value for the most recently added column
** of the table currently under construction.
**
................................................................................
  if( (p = pParse->pNewTable)!=0 ){
    pCol = &(p->aCol[p->nCol-1]);
    if( !sqlite3ExprIsConstantOrFunction(pExpr) ){
      sqlite3ErrorMsg(pParse, "default value of column [%s] is not constant",
          pCol->zName);
    }else{
      Expr *pCopy;
      sqlite3 *db = pParse->db;
      sqlite3ExprDelete(pCol->pDflt);
      pCol->pDflt = pCopy = sqlite3ExprDup(db, pExpr);
      if( pCopy ){
        sqlite3TokenCopy(db, &pCopy->span, &pExpr->span);
      }
    }
  }
  sqlite3ExprDelete(pExpr);
}

/*
................................................................................
*/
void sqlite3AddCheckConstraint(
  Parse *pParse,    /* Parsing context */
  Expr *pCheckExpr  /* The check expression */
){
#ifndef SQLITE_OMIT_CHECK
  Table *pTab = pParse->pNewTable;
  sqlite3 *db = pParse->db;
  if( pTab && !IN_DECLARE_VTAB ){
    /* The CHECK expression must be duplicated so that tokens refer
    ** to malloced space and not the (ephemeral) text of the CREATE TABLE
    ** statement */
    pTab->pCheck = sqlite3ExprAnd(db, pTab->pCheck, 
                                  sqlite3ExprDup(db, pCheckExpr));
  }
#endif
  sqlite3ExprDelete(pCheckExpr);
}

/*
** Set the collation function of the most recently parsed table column
................................................................................
  int i;

  if( (p = pParse->pNewTable)==0 ) return;
  i = p->nCol-1;

  if( sqlite3LocateCollSeq(pParse, zType, nType) ){
    Index *pIdx;
    p->aCol[i].zColl = sqlite3DbStrNDup(pParse->db, zType, nType);
  
    /* If the column is declared as "<name> PRIMARY KEY COLLATE <type>",
    ** then an index may have been created on this column before the
    ** collation type was added. Correct this if it is the case.
    */
    for(pIdx=p->pIndex; pIdx; pIdx=pIdx->pNext){
      assert( pIdx->nColumn==1 );
................................................................................
    zEnd = ")";
  }else{
    zSep = "\n  ";
    zSep2 = ",\n  ";
    zEnd = "\n)";
  }
  n += 35 + 6*p->nCol;
  zStmt = sqlite3_malloc( n );
  if( zStmt==0 ) return 0;
  sqlite3_snprintf(n, zStmt,
                  !OMIT_TEMPDB&&isTemp ? "CREATE TEMP TABLE ":"CREATE TABLE ");
  k = strlen(zStmt);
  identPut(zStmt, &k, p->zName);
  zStmt[k++] = '(';
  for(pCol=p->aCol, i=0; i<p->nCol; i++, pCol++){
................................................................................
  Token *pEnd,            /* The final ')' token in the CREATE TABLE */
  Select *pSelect         /* Select from a "CREATE ... AS SELECT" */
){
  Table *p;
  sqlite3 *db = pParse->db;
  int iDb;

  if( (pEnd==0 && pSelect==0) || pParse->nErr || db->mallocFailed ) {
    return;
  }
  p = pParse->pNewTable;
  if( p==0 ) return;

  assert( !db->init.busy || !pSelect );

................................................................................
       "WHERE rowid=#1",
      db->aDb[iDb].zName, SCHEMA_TABLE(iDb),
      zType,
      p->zName,
      p->zName,
      zStmt
    );
    sqlite3_free(zStmt);
    sqlite3ChangeCookie(db, v, iDb);

#ifndef SQLITE_OMIT_AUTOINCREMENT
    /* Check to see if we need to create an sqlite_sequence table for
    ** keeping track of autoincrement keys.
    */
    if( p->autoInc ){
................................................................................
  if( db->init.busy && pParse->nErr==0 ){
    Table *pOld;
    FKey *pFKey; 
    Schema *pSchema = p->pSchema;
    pOld = sqlite3HashInsert(&pSchema->tblHash, p->zName, strlen(p->zName)+1,p);
    if( pOld ){
      assert( p==pOld );  /* Malloc must have failed inside HashInsert() */
      db->mallocFailed = 1;
      return;
    }
#ifndef SQLITE_OMIT_FOREIGN_KEY
    for(pFKey=p->pFKey; pFKey; pFKey=pFKey->pNextFrom){
      int nTo = strlen(pFKey->zTo) + 1;
      pFKey->pNextTo = sqlite3HashFind(&pSchema->aFKey, pFKey->zTo, nTo);
      sqlite3HashInsert(&pSchema->aFKey, pFKey->zTo, nTo, pFKey);
................................................................................
  Table *p;
  int n;
  const unsigned char *z;
  Token sEnd;
  DbFixer sFix;
  Token *pName;
  int iDb;
  sqlite3 *db = pParse->db;

  if( pParse->nVar>0 ){
    sqlite3ErrorMsg(pParse, "parameters are not allowed in views");
    sqlite3SelectDelete(pSelect);
    return;
  }
  sqlite3StartTable(pParse, pName1, pName2, isTemp, 1, 0, noErr);
  p = pParse->pNewTable;
  if( p==0 || pParse->nErr ){
    sqlite3SelectDelete(pSelect);
    return;
  }
  sqlite3TwoPartName(pParse, pName1, pName2, &pName);
  iDb = sqlite3SchemaToIndex(db, p->pSchema);
  if( sqlite3FixInit(&sFix, pParse, iDb, "view", pName)
    && sqlite3FixSelect(&sFix, pSelect)
  ){
    sqlite3SelectDelete(pSelect);
    return;
  }

  /* Make a copy of the entire SELECT statement that defines the view.
  ** This will force all the Expr.token.z values to be dynamically
  ** allocated rather than point to the input string - which means that
  ** they will persist after the current sqlite3_exec() call returns.
  */
  p->pSelect = sqlite3SelectDup(db, pSelect);
  sqlite3SelectDelete(pSelect);
  if( db->mallocFailed ){
    return;
  }
  if( !db->init.busy ){
    sqlite3ViewGetColumnNames(pParse, p);
  }

  /* Locate the end of the CREATE VIEW statement.  Make sEnd point to
  ** the end.
  */
  sEnd = pParse->sLastToken;
................................................................................
** of errors.  If an error is seen leave an error message in pParse->zErrMsg.
*/
int sqlite3ViewGetColumnNames(Parse *pParse, Table *pTable){
  Table *pSelTab;   /* A fake table from which we get the result set */
  Select *pSel;     /* Copy of the SELECT that implements the view */
  int nErr = 0;     /* Number of errors encountered */
  int n;            /* Temporarily holds the number of cursors assigned */
  sqlite3 *db = pParse->db;  /* Database connection for malloc errors */

  assert( pTable );

#ifndef SQLITE_OMIT_VIRTUALTABLE
  if( sqlite3VtabCallConnect(pParse, pTable) ){
    return SQLITE_ERROR;
  }
................................................................................
  ** Note that the call to sqlite3ResultSetOfSelect() will expand any
  ** "*" elements in the results set of the view and will assign cursors
  ** to the elements of the FROM clause.  But we do not want these changes
  ** to be permanent.  So the computation is done on a copy of the SELECT
  ** statement that defines the view.
  */
  assert( pTable->pSelect );
  pSel = sqlite3SelectDup(db, pTable->pSelect);
  if( pSel ){
    n = pParse->nTab;
    sqlite3SrcListAssignCursors(pParse, pSel->pSrc);
    pTable->nCol = -1;
    pSelTab = sqlite3ResultSetOfSelect(pParse, 0, pSel);
    pParse->nTab = n;
    if( pSelTab ){
................................................................................
*/
void sqlite3DropTable(Parse *pParse, SrcList *pName, int isView, int noErr){
  Table *pTab;
  Vdbe *v;
  sqlite3 *db = pParse->db;
  int iDb;

  if( pParse->nErr || db->mallocFailed ){
    goto exit_drop_table;
  }
  assert( pName->nSrc==1 );
  pTab = sqlite3LocateTable(pParse, pName->a[0].zName, pName->a[0].zDatabase);

  if( pTab==0 ){
    if( noErr ){
................................................................................
  }
  nByte = sizeof(*pFKey) + nCol*sizeof(pFKey->aCol[0]) + pTo->n + 1;
  if( pToCol ){
    for(i=0; i<pToCol->nExpr; i++){
      nByte += strlen(pToCol->a[i].zName) + 1;
    }
  }
  pFKey = sqlite3DbMallocZero(pParse->db, nByte );
  if( pFKey==0 ){
    goto fk_end;
  }
  pFKey->pFrom = p;
  pFKey->pNextFrom = p->pFKey;
  z = (char*)&pFKey[1];
  pFKey->aCol = (struct sColMap*)z;
  z += sizeof(struct sColMap)*nCol;
  pFKey->zTo = z;
  memcpy(z, pTo->z, pTo->n);
................................................................................

  /* Link the foreign key to the table as the last step.
  */
  p->pFKey = pFKey;
  pFKey = 0;

fk_end:
  sqlite3_free(pFKey);
#endif /* !defined(SQLITE_OMIT_FOREIGN_KEY) */
  sqlite3ExprListDelete(pFromCol);
  sqlite3ExprListDelete(pToCol);
}

/*
** This routine is called when an INITIALLY IMMEDIATE or INITIALLY DEFERRED
................................................................................
  Table *pTab = pIndex->pTable;  /* The table that is indexed */
  int iTab = pParse->nTab;       /* Btree cursor used for pTab */
  int iIdx = pParse->nTab+1;     /* Btree cursor used for pIndex */
  int addr1;                     /* Address of top of loop */
  int tnum;                      /* Root page of index */
  Vdbe *v;                       /* Generate code into this virtual machine */
  KeyInfo *pKey;                 /* KeyInfo for index */
  sqlite3 *db = pParse->db;      /* The database connection */
  int iDb = sqlite3SchemaToIndex(db, pIndex->pSchema);

#ifndef SQLITE_OMIT_AUTHORIZATION
  if( sqlite3AuthCheck(pParse, SQLITE_REINDEX, pIndex->zName, 0,
      db->aDb[iDb].zName ) ){
    return;
  }
#endif

  /* Require a write-lock on the table to perform this operation */
  sqlite3TableLock(pParse, iDb, pTab->tnum, 1, pTab->zName);

................................................................................
    int addr2 = curaddr+4;
    sqlite3VdbeChangeP2(v, curaddr-1, addr2);
    sqlite3VdbeAddOp(v, OP_Rowid, iTab, 0);
    sqlite3VdbeAddOp(v, OP_AddImm, 1, 0);
    sqlite3VdbeAddOp(v, OP_IsUnique, iIdx, addr2);
    sqlite3VdbeOp3(v, OP_Halt, SQLITE_CONSTRAINT, OE_Abort,
                    "indexed columns are not unique", P3_STATIC);
    assert( db->mallocFailed || addr2==sqlite3VdbeCurrentAddr(v) );
  }
  sqlite3VdbeAddOp(v, OP_IdxInsert, iIdx, 0);
  sqlite3VdbeAddOp(v, OP_Next, iTab, addr1+1);
  sqlite3VdbeJumpHere(v, addr1);
  sqlite3VdbeAddOp(v, OP_Close, iTab, 0);
  sqlite3VdbeAddOp(v, OP_Close, iIdx, 0);
}
................................................................................
  int iDb;             /* Index of the database that is being written */
  Token *pName = 0;    /* Unqualified name of the index to create */
  struct ExprList_item *pListItem; /* For looping over pList */
  int nCol;
  int nExtra = 0;
  char *zExtra;

  if( pParse->nErr || db->mallocFailed || IN_DECLARE_VTAB ){
    goto exit_create_index;
  }

  /*
  ** Find the table that is to be indexed.  Return early if not found.
  */
  if( pTblName!=0 ){
................................................................................
  ** index, then we will continue to process this index.
  **
  ** If pName==0 it means that we are
  ** dealing with a primary key or UNIQUE constraint.  We have to invent our
  ** own name.
  */
  if( pName ){
    zName = sqlite3NameFromToken(db, pName);
    if( SQLITE_OK!=sqlite3ReadSchema(pParse) ) goto exit_create_index;
    if( zName==0 ) goto exit_create_index;
    if( SQLITE_OK!=sqlite3CheckObjectName(pParse, zName) ){
      goto exit_create_index;
    }
    if( !db->init.busy ){
      if( SQLITE_OK!=sqlite3ReadSchema(pParse) ) goto exit_create_index;
................................................................................
  }

  /* 
  ** Allocate the index structure. 
  */
  nName = strlen(zName);
  nCol = pList->nExpr;
  pIndex = sqlite3DbMallocZero(db, 
      sizeof(Index) +              /* Index structure  */
      sizeof(int)*nCol +           /* Index.aiColumn   */
      sizeof(int)*(nCol+1) +       /* Index.aiRowEst   */
      sizeof(char *)*nCol +        /* Index.azColl     */
      sizeof(u8)*nCol +            /* Index.aSortOrder */
      nName + 1 +                  /* Index.zName      */
      nExtra                       /* Collation sequence names */
  );
  if( db->mallocFailed ){
    goto exit_create_index;
  }
  pIndex->azColl = (char**)(&pIndex[1]);
  pIndex->aiColumn = (int *)(&pIndex->azColl[nCol]);
  pIndex->aiRowEst = (unsigned *)(&pIndex->aiColumn[nCol]);
  pIndex->aSortOrder = (u8 *)(&pIndex->aiRowEst[nCol+1]);
  pIndex->zName = (char *)(&pIndex->aSortOrder[nCol]);
  zExtra = (char *)(&pIndex->zName[nName+1]);
  memcpy(pIndex->zName, zName, nName+1);
................................................................................
  */
  if( db->init.busy ){
    Index *p;
    p = sqlite3HashInsert(&pIndex->pSchema->idxHash, 
                         pIndex->zName, strlen(pIndex->zName)+1, pIndex);
    if( p ){
      assert( p==pIndex );  /* Malloc must have failed */
      db->mallocFailed = 1;
      goto exit_create_index;
    }
    db->flags |= SQLITE_InternChanges;
    if( pTblName!=0 ){
      pIndex->tnum = db->init.newTnum;
    }
  }
................................................................................
        "INSERT INTO %Q.%s VALUES('index',%Q,%Q,#0,%Q);",
        db->aDb[iDb].zName, SCHEMA_TABLE(iDb),
        pIndex->zName,
        pTab->zName,
        zStmt
    );
    sqlite3VdbeAddOp(v, OP_Pop, 1, 0);
    sqlite3_free(zStmt);

    /* Fill the index with data and reparse the schema. Code an OP_Expire
    ** to invalidate all pre-compiled statements.
    */
    if( pTblName ){
      sqlite3RefillIndex(pParse, pIndex, iMem);
      sqlite3ChangeCookie(db, v, iDb);
................................................................................
  /* Clean up before exiting */
exit_create_index:
  if( pIndex ){
    freeIndex(pIndex);
  }
  sqlite3ExprListDelete(pList);
  sqlite3SrcListDelete(pTblName);
  sqlite3_free(zName);
  return;
}

/*
** Generate code to make sure the file format number is at least minFormat.
** The generated code will increase the file format number if necessary.
*/
................................................................................
*/
void sqlite3DropIndex(Parse *pParse, SrcList *pName, int ifExists){
  Index *pIndex;
  Vdbe *v;
  sqlite3 *db = pParse->db;
  int iDb;

  if( pParse->nErr || db->mallocFailed ){
    goto exit_drop_index;
  }
  assert( pName->nSrc==1 );
  if( SQLITE_OK!=sqlite3ReadSchema(pParse) ){
    goto exit_drop_index;
  }
  pIndex = sqlite3FindIndex(db, pName->a[0].zName, pName->a[0].zDatabase);
................................................................................
** The index of the new entry is returned in *pIdx.
**
** This routine returns a pointer to the array of objects.  This
** might be the same as the pArray parameter or it might be a different
** pointer if the array was resized.
*/
void *sqlite3ArrayAllocate(
  sqlite3 *db,      /* Connection to notify of malloc failures */
  void *pArray,     /* Array of objects.  Might be reallocated */
  int szEntry,      /* Size of each object in the array */
  int initSize,     /* Suggested initial allocation, in elements */
  int *pnEntry,     /* Number of objects currently in use */
  int *pnAlloc,     /* Current size of the allocation, in elements */
  int *pIdx         /* Write the index of a new slot here */
){
  char *z;
  if( *pnEntry >= *pnAlloc ){
    void *pNew;
    int newSize;
    newSize = (*pnAlloc)*2 + initSize;
    pNew = sqlite3_realloc(pArray, newSize*szEntry);
    if( pNew==0 ){
      db->mallocFailed = 1;
      *pIdx = -1;
      return pArray;
    }
    *pnAlloc = newSize;
    pArray = pNew;
  }
  z = (char*)pArray;
................................................................................

/*
** Append a new element to the given IdList.  Create a new IdList if
** need be.
**
** A new IdList is returned, or NULL if malloc() fails.
*/
IdList *sqlite3IdListAppend(sqlite3 *db, IdList *pList, Token *pToken){
  int i;
  if( pList==0 ){
    pList = sqlite3DbMallocZero(db, sizeof(IdList) );
    if( pList==0 ) return 0;
    pList->nAlloc = 0;
  }
  pList->a = sqlite3ArrayAllocate(
      db,
      pList->a,
      sizeof(pList->a[0]),
      5,
      &pList->nId,
      &pList->nAlloc,
      &i
  );
  if( i<0 ){
    sqlite3IdListDelete(pList);
    return 0;
  }
  pList->a[i].zName = sqlite3NameFromToken(db, pToken);
  return pList;
}

/*
** Delete an IdList.
*/
void sqlite3IdListDelete(IdList *pList){
  int i;
  if( pList==0 ) return;
  for(i=0; i<pList->nId; i++){
    sqlite3_free(pList->a[i].zName);
  }
  sqlite3_free(pList->a);
  sqlite3_free(pList);
}

/*
** Return the index in pList of the identifier named zId.  Return -1
** if not found.
*/
int sqlite3IdListIndex(IdList *pList, const char *zName){
................................................................................
** The SrcList.a[].zName field is filled with the table name which might
** come from pTable (if pDatabase is NULL) or from pDatabase.  
** SrcList.a[].zDatabase is filled with the database name from pTable,
** or with NULL if no database is specified.
**
** In other words, if call like this:
**
**         sqlite3SrcListAppend(D,A,B,0);
**
** Then B is a table name and the database name is unspecified.  If called
** like this:
**
**         sqlite3SrcListAppend(D,A,B,C);
**
** Then C is the table name and B is the database name.
*/
SrcList *sqlite3SrcListAppend(
  sqlite3 *db,        /* Connection to notify of malloc failures */
  SrcList *pList,     /* Append to this SrcList. NULL creates a new SrcList */
  Token *pTable,      /* Table to append */
  Token *pDatabase    /* Database of the table */
){
  struct SrcList_item *pItem;
  if( pList==0 ){

    pList = sqlite3DbMallocZero(db, sizeof(SrcList) );
    if( pList==0 ) return 0;
    pList->nAlloc = 1;
  }
  if( pList->nSrc>=pList->nAlloc ){
    SrcList *pNew;
    pList->nAlloc *= 2;
    pNew = sqlite3_realloc(pList,
               sizeof(*pList) + (pList->nAlloc-1)*sizeof(pList->a[0]) );
    if( pNew==0 ){
      db->mallocFailed = 1;
      sqlite3SrcListDelete(pList);
      return 0;
    }
    pList = pNew;
  }
  pItem = &pList->a[pList->nSrc];
  memset(pItem, 0, sizeof(pList->a[0]));
................................................................................
    pDatabase = 0;
  }
  if( pDatabase && pTable ){
    Token *pTemp = pDatabase;
    pDatabase = pTable;
    pTable = pTemp;
  }
  pItem->zName = sqlite3NameFromToken(db, pTable);
  pItem->zDatabase = sqlite3NameFromToken(db, pDatabase);
  pItem->iCursor = -1;
  pItem->isPopulated = 0;
  pList->nSrc++;
  return pList;
}

/*
** Assign cursors to all tables in a SrcList
*/
void sqlite3SrcListAssignCursors(Parse *pParse, SrcList *pList){
  int i;
  struct SrcList_item *pItem;
  assert(pList || pParse->db->mallocFailed );
  if( pList ){
    for(i=0, pItem=pList->a; i<pList->nSrc; i++, pItem++){
      if( pItem->iCursor>=0 ) break;
      pItem->iCursor = pParse->nTab++;
      if( pItem->pSelect ){
        sqlite3SrcListAssignCursors(pParse, pItem->pSelect->pSrc);
      }
................................................................................
** Delete an entire SrcList including all its substructure.
*/
void sqlite3SrcListDelete(SrcList *pList){
  int i;
  struct SrcList_item *pItem;
  if( pList==0 ) return;
  for(pItem=pList->a, i=0; i<pList->nSrc; i++, pItem++){
    sqlite3_free(pItem->zDatabase);
    sqlite3_free(pItem->zName);
    sqlite3_free(pItem->zAlias);
    sqlite3DeleteTable(pItem->pTab);
    sqlite3SelectDelete(pItem->pSelect);
    sqlite3ExprDelete(pItem->pOn);
    sqlite3IdListDelete(pItem->pUsing);
  }
  sqlite3_free(pList);
}

/*
** This routine is called by the parser to add a new term to the
** end of a growing FROM clause.  The "p" parameter is the part of
** the FROM clause that has already been constructed.  "p" is NULL
** if this is the first term of the FROM clause.  pTable and pDatabase
................................................................................
** pDatabase parameters are NULL for subqueries.  The pOn and pUsing
** parameters are the content of the ON and USING clauses.
**
** Return a new SrcList which encodes is the FROM with the new
** term added.
*/
SrcList *sqlite3SrcListAppendFromTerm(
  Parse *pParse,          /* Parsing context */
  SrcList *p,             /* The left part of the FROM clause already seen */
  Token *pTable,          /* Name of the table to add to the FROM clause */
  Token *pDatabase,       /* Name of the database containing pTable */
  Token *pAlias,          /* The right-hand side of the AS subexpression */
  Select *pSubquery,      /* A subquery used in place of a table name */
  Expr *pOn,              /* The ON clause of a join */
  IdList *pUsing          /* The USING clause of a join */
){
  struct SrcList_item *pItem;
  sqlite3 *db = pParse->db;
  p = sqlite3SrcListAppend(db, p, pTable, pDatabase);
  if( p==0 || p->nSrc==0 ){
    sqlite3ExprDelete(pOn);
    sqlite3IdListDelete(pUsing);
    sqlite3SelectDelete(pSubquery);
    return p;
  }
  pItem = &p->a[p->nSrc-1];
  if( pAlias && pAlias->n ){
    pItem->zAlias = sqlite3NameFromToken(db, pAlias);
  }
  pItem->pSelect = pSubquery;
  pItem->pOn = pOn;
  pItem->pUsing = pUsing;
  return p;
}

................................................................................
*/
void sqlite3BeginTransaction(Parse *pParse, int type){
  sqlite3 *db;
  Vdbe *v;
  int i;

  if( pParse==0 || (db=pParse->db)==0 || db->aDb[0].pBt==0 ) return;
  if( pParse->nErr || db->mallocFailed ) return;
  if( sqlite3AuthCheck(pParse, SQLITE_TRANSACTION, "BEGIN", 0, 0) ) return;

  v = sqlite3GetVdbe(pParse);
  if( !v ) return;
  if( type!=TK_DEFERRED ){
    for(i=0; i<db->nDb; i++){
      sqlite3VdbeAddOp(v, OP_Transaction, i, (type==TK_EXCLUSIVE)+1);
................................................................................
** Commit a transaction
*/
void sqlite3CommitTransaction(Parse *pParse){
  sqlite3 *db;
  Vdbe *v;

  if( pParse==0 || (db=pParse->db)==0 || db->aDb[0].pBt==0 ) return;
  if( pParse->nErr || db->mallocFailed ) return;
  if( sqlite3AuthCheck(pParse, SQLITE_TRANSACTION, "COMMIT", 0, 0) ) return;

  v = sqlite3GetVdbe(pParse);
  if( v ){
    sqlite3VdbeAddOp(v, OP_AutoCommit, 1, 0);
  }
}
................................................................................
** Rollback a transaction
*/
void sqlite3RollbackTransaction(Parse *pParse){
  sqlite3 *db;
  Vdbe *v;

  if( pParse==0 || (db=pParse->db)==0 || db->aDb[0].pBt==0 ) return;
  if( pParse->nErr || db->mallocFailed ) return;
  if( sqlite3AuthCheck(pParse, SQLITE_TRANSACTION, "ROLLBACK", 0, 0) ) return;

  v = sqlite3GetVdbe(pParse);
  if( v ){
    sqlite3VdbeAddOp(v, OP_AutoCommit, 1, 1);
  }
}
................................................................................
  if( pName1==0 || pName1->z==0 ){
    reindexDatabases(pParse, 0);
    return;
  }else if( pName2==0 || pName2->z==0 ){
    assert( pName1->z );
    pColl = sqlite3FindCollSeq(db, ENC(db), (char*)pName1->z, pName1->n, 0);
    if( pColl ){
      char *zColl = sqlite3DbStrNDup(db, (const char *)pName1->z, pName1->n);
      if( zColl ){
        reindexDatabases(pParse, zColl);
        sqlite3_free(zColl);
      }
      return;
    }
  }
  iDb = sqlite3TwoPartName(pParse, pName1, pName2, &pObjName);
  if( iDb<0 ) return;
  z = sqlite3NameFromToken(db, pObjName);
  if( z==0 ) return;
  zDb = db->aDb[iDb].zName;
  pTab = sqlite3FindTable(db, z, zDb);
  if( pTab ){
    reindexTable(pParse, pTab, 0);
    sqlite3_free(z);
    return;
  }
  pIndex = sqlite3FindIndex(db, z, zDb);
  sqlite3_free(z);
  if( pIndex ){
    sqlite3BeginWriteOperation(pParse, 0, iDb);
    sqlite3RefillIndex(pParse, pIndex, -1);
    return;
  }
  sqlite3ErrorMsg(pParse, "unable to identify the object to be reindexed");
}
................................................................................
#endif

/*
** Return a dynamicly allocated KeyInfo structure that can be used
** with OP_OpenRead or OP_OpenWrite to access database index pIdx.
**
** If successful, a pointer to the new structure is returned. In this case
** the caller is responsible for calling sqlite3_free() on the returned 
** pointer. If an error occurs (out of memory or missing collation 
** sequence), NULL is returned and the state of pParse updated to reflect
** the error.
*/
KeyInfo *sqlite3IndexKeyinfo(Parse *pParse, Index *pIdx){
  int i;
  int nCol = pIdx->nColumn;
  int nBytes = sizeof(KeyInfo) + (nCol-1)*sizeof(CollSeq*) + nCol;
  KeyInfo *pKey = (KeyInfo *)sqlite3DbMallocZer(pParse->db, nBytes);

  if( pKey ){
    pKey->aSortOrder = (u8 *)&(pKey->aColl[nCol]);
    assert( &pKey->aSortOrder[nCol]==&(((u8 *)pKey)[nBytes]) );
    for(i=0; i<nCol; i++){
      char *zColl = pIdx->azColl[i];
      assert( zColl );
................................................................................
      pKey->aColl[i] = sqlite3LocateCollSeq(pParse, zColl, -1);
      pKey->aSortOrder[i] = pIdx->aSortOrder[i];
    }
    pKey->nField = nCol;
  }

  if( pParse->nErr ){
    sqlite3_free(pKey);
    pKey = 0;
  }
  return pKey;
}

**    May you share freely, never taking more than you give.
**
*************************************************************************
**
** This file contains functions used to access the internal hash tables
** of user defined functions and collation sequences.
**
** $Id: callback.c,v 1.18 2007/05/07 09:32:45 danielk1977 Exp $
*/

#include "sqliteInt.h"

/*
** Invoke the 'collation needed' callback to request a collation sequence
** in the database text encoding of name zName, length nName.
** If the collation sequence
*/
static void callCollNeeded(sqlite3 *db, const char *zName, int nName){
  assert( !db->xCollNeeded || !db->xCollNeeded16 );
  if( nName<0 ) nName = strlen(zName);
  if( db->xCollNeeded ){
    char *zExternal = sqliteStrNDup(zName, nName);
    if( !zExternal ) return;
    db->xCollNeeded(db->pCollNeededArg, db, (int)ENC(db), zExternal);
    sqliteFree(zExternal);
  }
#ifndef SQLITE_OMIT_UTF16
  if( db->xCollNeeded16 ){
    char const *zExternal;
    sqlite3_value *pTmp = sqlite3ValueNew();
    sqlite3ValueSetStr(pTmp, nName, zName, SQLITE_UTF8, SQLITE_STATIC);
    zExternal = sqlite3ValueText(pTmp, SQLITE_UTF16NATIVE);
................................................................................
  int create
){
  CollSeq *pColl;
  if( nName<0 ) nName = strlen(zName);
  pColl = sqlite3HashFind(&db->aCollSeq, zName, nName);

  if( 0==pColl && create ){
    pColl = sqliteMalloc( 3*sizeof(*pColl) + nName + 1 );
    if( pColl ){
      CollSeq *pDel = 0;
      pColl[0].zName = (char*)&pColl[3];
      pColl[0].enc = SQLITE_UTF8;
      pColl[1].zName = (char*)&pColl[3];
      pColl[1].enc = SQLITE_UTF16LE;
      pColl[2].zName = (char*)&pColl[3];
................................................................................
      pColl[0].zName[nName] = 0;
      pDel = sqlite3HashInsert(&db->aCollSeq, pColl[0].zName, nName, pColl);

      /* If a malloc() failure occured in sqlite3HashInsert(), it will 
      ** return the pColl pointer to be deleted (because it wasn't added
      ** to the hash table).
      */
      assert( !pDel || (sqlite3MallocFailed() && pDel==pColl) );
      if( pDel ){
        sqliteFree(pDel);
        pColl = 0;
      }
    }
  }
  return pColl;
}

................................................................................
  }

  /* If the createFlag parameter is true, and the seach did not reveal an
  ** exact match for the name, number of arguments and encoding, then add a
  ** new entry to the hash table and return it.
  */
  if( createFlag && bestmatch<6 && 
      (pBest = sqliteMalloc(sizeof(*pBest)+nName))!=0 ){
    pBest->nArg = nArg;
    pBest->pNext = pFirst;
    pBest->iPrefEnc = enc;
    memcpy(pBest->zName, zName, nName);
    pBest->zName[nName] = 0;
    if( pBest==sqlite3HashInsert(&db->aFunc,pBest->zName,nName,(void*)pBest) ){
      sqliteFree(pBest);
      return 0;
    }
  }

  if( pBest && (pBest->xStep || pBest->xFunc || createFlag) ){
    return pBest;
  }
  return 0;
}

/*
** Free all resources held by the schema structure. The void* argument points
** at a Schema struct. This function does not call sqliteFree() on the 
** pointer itself, it just cleans up subsiduary resources (i.e. the contents
** of the schema hash tables).
*/
void sqlite3SchemaFree(void *p){
  Hash temp1;
  Hash temp2;
  HashElem *pElem;
................................................................................
  pSchema->flags &= ~DB_SchemaLoaded;
}

/*
** Find and return the schema associated with a BTree.  Create
** a new one if necessary.
*/
Schema *sqlite3SchemaGet(Btree *pBt){
  Schema * p;
  if( pBt ){
    p = (Schema *)sqlite3BtreeSchema(pBt,sizeof(Schema),sqlite3SchemaFree);
  }else{
    p = (Schema *)sqliteMalloc(sizeof(Schema));
  }
  if( p && 0==p->file_format ){
    sqlite3HashInit(&p->tblHash, SQLITE_HASH_STRING, 0);
    sqlite3HashInit(&p->idxHash, SQLITE_HASH_STRING, 0);
    sqlite3HashInit(&p->trigHash, SQLITE_HASH_STRING, 0);
    sqlite3HashInit(&p->aFKey, SQLITE_HASH_STRING, 1);
    p->enc = SQLITE_UTF8;
  }
  return p;
}

**    May you share freely, never taking more than you give.
**
*************************************************************************
**
** This file contains functions used to access the internal hash tables
** of user defined functions and collation sequences.
**
** $Id: callback.c,v 1.19 2007/08/16 04:30:39 drh Exp $
*/

#include "sqliteInt.h"

/*
** Invoke the 'collation needed' callback to request a collation sequence
** in the database text encoding of name zName, length nName.
** If the collation sequence
*/
static void callCollNeeded(sqlite3 *db, const char *zName, int nName){
  assert( !db->xCollNeeded || !db->xCollNeeded16 );
  if( nName<0 ) nName = strlen(zName);
  if( db->xCollNeeded ){
    char *zExternal = sqlite3DbStrNDup(db, zName, nName);
    if( !zExternal ) return;
    db->xCollNeeded(db->pCollNeededArg, db, (int)ENC(db), zExternal);
    sqlite3_free(zExternal);
  }
#ifndef SQLITE_OMIT_UTF16
  if( db->xCollNeeded16 ){
    char const *zExternal;
    sqlite3_value *pTmp = sqlite3ValueNew();
    sqlite3ValueSetStr(pTmp, nName, zName, SQLITE_UTF8, SQLITE_STATIC);
    zExternal = sqlite3ValueText(pTmp, SQLITE_UTF16NATIVE);
................................................................................
  int create
){
  CollSeq *pColl;
  if( nName<0 ) nName = strlen(zName);
  pColl = sqlite3HashFind(&db->aCollSeq, zName, nName);

  if( 0==pColl && create ){
    pColl = sqlite3DbMallocZero(db, 3*sizeof(*pColl) + nName + 1 );
    if( pColl ){
      CollSeq *pDel = 0;
      pColl[0].zName = (char*)&pColl[3];
      pColl[0].enc = SQLITE_UTF8;
      pColl[1].zName = (char*)&pColl[3];
      pColl[1].enc = SQLITE_UTF16LE;
      pColl[2].zName = (char*)&pColl[3];
................................................................................
      pColl[0].zName[nName] = 0;
      pDel = sqlite3HashInsert(&db->aCollSeq, pColl[0].zName, nName, pColl);

      /* If a malloc() failure occured in sqlite3HashInsert(), it will 
      ** return the pColl pointer to be deleted (because it wasn't added
      ** to the hash table).
      */
      assert( !pDel || (db->mallocFailed && pDel==pColl) );
      if( pDel ){
        sqlite3_free(pDel);
        pColl = 0;
      }
    }
  }
  return pColl;
}

................................................................................
  }

  /* If the createFlag parameter is true, and the seach did not reveal an
  ** exact match for the name, number of arguments and encoding, then add a
  ** new entry to the hash table and return it.
  */
  if( createFlag && bestmatch<6 && 
      (pBest = sqlite3DbMallocZero(db, sizeof(*pBest)+nName))!=0 ){
    pBest->nArg = nArg;
    pBest->pNext = pFirst;
    pBest->iPrefEnc = enc;
    memcpy(pBest->zName, zName, nName);
    pBest->zName[nName] = 0;
    if( pBest==sqlite3HashInsert(&db->aFunc,pBest->zName,nName,(void*)pBest) ){
      sqlite3_free(pBest);
      return 0;
    }
  }

  if( pBest && (pBest->xStep || pBest->xFunc || createFlag) ){
    return pBest;
  }
  return 0;
}

/*
** Free all resources held by the schema structure. The void* argument points
** at a Schema struct. This function does not call sqlite3_free() on the 
** pointer itself, it just cleans up subsiduary resources (i.e. the contents
** of the schema hash tables).
*/
void sqlite3SchemaFree(void *p){
  Hash temp1;
  Hash temp2;
  HashElem *pElem;
................................................................................
  pSchema->flags &= ~DB_SchemaLoaded;
}

/*
** Find and return the schema associated with a BTree.  Create
** a new one if necessary.
*/
Schema *sqlite3SchemaGet(sqlite3 *db, Btree *pBt){
  Schema * p;
  if( pBt ){
    p = (Schema *)sqlite3BtreeSchema(pBt,sizeof(Schema),sqlite3SchemaFree);
  }else{
    p = (Schema *)sqlite3DbMallocZero(db,sizeof(Schema));
  }
  if( p && 0==p->file_format ){
    sqlite3HashInit(&p->tblHash, SQLITE_HASH_STRING, 0);
    sqlite3HashInit(&p->idxHash, SQLITE_HASH_STRING, 0);
    sqlite3HashInit(&p->trigHash, SQLITE_HASH_STRING, 0);
    sqlite3HashInit(&p->aFKey, SQLITE_HASH_STRING, 1);
    p->enc = SQLITE_UTF8;
  }
  return p;
}

** This file contains the C functions that implement date and time
** functions for SQLite.  
**
** There is only one exported symbol in this file - the function
** sqlite3RegisterDateTimeFunctions() found at the bottom of the file.
** All other code has file scope.
**
** $Id: date.c,v 1.66 2007/05/08 21:56:00 drh Exp $
**
** SQLite processes all times and dates as Julian Day numbers.  The
** dates and times are stored as the number of days since noon
** in Greenwich on November 24, 4714 B.C. according to the Gregorian
** calendar system. 
**
** 1970-01-01 00:00:00 is JD 2440587.5
................................................................................
  }
  if( n<sizeof(zBuf) ){
    z = zBuf;
  }else if( n>SQLITE_MAX_LENGTH ){
    sqlite3_result_error_toobig(context);
    return;
  }else{
    z = sqliteMalloc( n );
    if( z==0 ) return;
  }
  computeJD(&x);
  computeYMD_HMS(&x);
  for(i=j=0; zFmt[i]; i++){
    if( zFmt[i]!='%' ){
      z[j++] = zFmt[i];
................................................................................
        case '%':  z[j++] = '%'; break;
      }
    }
  }
  z[j] = 0;
  sqlite3_result_text(context, z, -1, SQLITE_TRANSIENT);
  if( z!=zBuf ){
    sqliteFree(z);
  }
}

/*
** current_time()
**
** This function returns the same value as time('now').

** This file contains the C functions that implement date and time
** functions for SQLite.  
**
** There is only one exported symbol in this file - the function
** sqlite3RegisterDateTimeFunctions() found at the bottom of the file.
** All other code has file scope.
**
** $Id: date.c,v 1.67 2007/08/16 04:30:40 drh Exp $
**
** SQLite processes all times and dates as Julian Day numbers.  The
** dates and times are stored as the number of days since noon
** in Greenwich on November 24, 4714 B.C. according to the Gregorian
** calendar system. 
**
** 1970-01-01 00:00:00 is JD 2440587.5
................................................................................
  }
  if( n<sizeof(zBuf) ){
    z = zBuf;
  }else if( n>SQLITE_MAX_LENGTH ){
    sqlite3_result_error_toobig(context);
    return;
  }else{
    z = sqlite3_malloc( n );
    if( z==0 ) return;
  }
  computeJD(&x);
  computeYMD_HMS(&x);
  for(i=j=0; zFmt[i]; i++){
    if( zFmt[i]!='%' ){
      z[j++] = zFmt[i];
................................................................................
        case '%':  z[j++] = '%'; break;
      }
    }
  }
  z[j] = 0;
  sqlite3_result_text(context, z, -1, SQLITE_TRANSIENT);
  if( z!=zBuf ){
    sqlite3_free(z);
  }
}

/*
** current_time()
**
** This function returns the same value as time('now').

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains C code routines that are called by the parser
** in order to generate code for DELETE FROM statements.
**
** $Id: delete.c,v 1.129 2007/04/16 15:06:25 danielk1977 Exp $
*/
#include "sqliteInt.h"

/*
** Look up every table that is named in pSrc.  If any table is not found,
** add an error message to pParse->zErrMsg and return NULL.  If all tables
** are found, return a pointer to the last table.
................................................................................

#ifndef SQLITE_OMIT_TRIGGER
  int isView;                  /* True if attempting to delete from a view */
  int triggers_exist = 0;      /* True if any triggers exist */
#endif

  sContext.pParse = 0;

  if( pParse->nErr || sqlite3MallocFailed() ){
    goto delete_from_cleanup;
  }
  db = pParse->db;
  assert( pTabList->nSrc==1 );

  /* Locate the table which we want to delete.  This table has to be
  ** put in an SrcList structure because some of the subroutines we
  ** will be calling are designed to work with multiple tables and expect
  ** an SrcList* parameter instead of just a Table* parameter.
  */
................................................................................
  if( pParse->nested==0 ) sqlite3VdbeCountChanges(v);
  sqlite3BeginWriteOperation(pParse, triggers_exist, iDb);

  /* If we are trying to delete from a view, realize that view into
  ** a ephemeral table.
  */
  if( isView ){
    Select *pView = sqlite3SelectDup(pTab->pSelect);
    sqlite3Select(pParse, pView, SRT_EphemTab, iCur, 0, 0, 0, 0);
    sqlite3SelectDelete(pView);
  }

  /* Initialize the counter of the number of rows deleted, if
  ** we are counting rows.
  */

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains C code routines that are called by the parser
** in order to generate code for DELETE FROM statements.
**
** $Id: delete.c,v 1.130 2007/08/16 04:30:40 drh Exp $
*/
#include "sqliteInt.h"

/*
** Look up every table that is named in pSrc.  If any table is not found,
** add an error message to pParse->zErrMsg and return NULL.  If all tables
** are found, return a pointer to the last table.
................................................................................

#ifndef SQLITE_OMIT_TRIGGER
  int isView;                  /* True if attempting to delete from a view */
  int triggers_exist = 0;      /* True if any triggers exist */
#endif

  sContext.pParse = 0;
  db = pParse->db;
  if( pParse->nErr || db->mallocFailed ){
    goto delete_from_cleanup;
  }

  assert( pTabList->nSrc==1 );

  /* Locate the table which we want to delete.  This table has to be
  ** put in an SrcList structure because some of the subroutines we
  ** will be calling are designed to work with multiple tables and expect
  ** an SrcList* parameter instead of just a Table* parameter.
  */
................................................................................
  if( pParse->nested==0 ) sqlite3VdbeCountChanges(v);
  sqlite3BeginWriteOperation(pParse, triggers_exist, iDb);

  /* If we are trying to delete from a view, realize that view into
  ** a ephemeral table.
  */
  if( isView ){
    Select *pView = sqlite3SelectDup(db, pTab->pSelect);
    sqlite3Select(pParse, pView, SRT_EphemTab, iCur, 0, 0, 0, 0);
    sqlite3SelectDelete(pView);
  }

  /* Initialize the counter of the number of rows deleted, if
  ** we are counting rows.
  */

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains routines used for analyzing expressions and
** for generating VDBE code that evaluates expressions in SQLite.
**
** $Id: expr.c,v 1.303 2007/08/07 17:13:04 drh Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>

/*
** Return the 'affinity' of the expression pExpr if any.
**
................................................................................
  int p1 = binaryCompareP1(pLeft, pRight, jumpIfNull);
  CollSeq *p3 = sqlite3BinaryCompareCollSeq(pParse, pLeft, pRight);
  return sqlite3VdbeOp3(pParse->pVdbe, opcode, p1, dest, (void*)p3, P3_COLLSEQ);
}

/*
** Construct a new expression node and return a pointer to it.  Memory
** for this node is obtained from sqliteMalloc().  The calling function
** is responsible for making sure the node eventually gets freed.
*/
Expr *sqlite3Expr(int op, Expr *pLeft, Expr *pRight, const Token *pToken){





  Expr *pNew;
  pNew = sqliteMalloc( sizeof(Expr) );
  if( pNew==0 ){
    /* When malloc fails, delete pLeft and pRight. Expressions passed to 
    ** this function must always be allocated with sqlite3Expr() for this 
    ** reason. 
    */
    sqlite3ExprDelete(pLeft);
    sqlite3ExprDelete(pRight);
................................................................................
  }

  sqlite3ExprSetHeight(pNew);
  return pNew;
}

/*
** Works like sqlite3Expr() but frees its pLeft and pRight arguments
** if it fails due to a malloc problem.
*/
Expr *sqlite3ExprOrFree(int op, Expr *pLeft, Expr *pRight, const Token *pToken){






  Expr *pNew = sqlite3Expr(op, pLeft, pRight, pToken);
  if( pNew==0 ){
    sqlite3ExprDelete(pLeft);
    sqlite3ExprDelete(pRight);

  }
  return pNew;
}

/*
** When doing a nested parse, you can include terms in an expression
** that look like this:   #0 #1 #2 ...  These terms refer to elements
................................................................................
  if( pParse->nested==0 ){
    sqlite3ErrorMsg(pParse, "near \"%T\": syntax error", pToken);
    return sqlite3Expr(TK_NULL, 0, 0, 0);
  }
  if( v==0 ) return 0;
  p = sqlite3Expr(TK_REGISTER, 0, 0, pToken);
  if( p==0 ){

    return 0;  /* Malloc failed */
  }
  depth = atoi((char*)&pToken->z[1]);
  p->iTable = pParse->nMem++;
  sqlite3VdbeAddOp(v, OP_Dup, depth, 0);
  sqlite3VdbeAddOp(v, OP_MemStore, p->iTable, 1);
  return p;
}

/*
** Join two expressions using an AND operator.  If either expression is
** NULL, then just return the other expression.
*/
Expr *sqlite3ExprAnd(Expr *pLeft, Expr *pRight){
  if( pLeft==0 ){
    return pRight;
  }else if( pRight==0 ){
    return pLeft;
  }else{
    return sqlite3Expr(TK_AND, pLeft, pRight, 0);



  }
}

/*
** Set the Expr.span field of the given expression to span all
** text between the two given tokens.
*/
void sqlite3ExprSpan(Expr *pExpr, Token *pLeft, Token *pRight){
  assert( pRight!=0 );
  assert( pLeft!=0 );
  if( !sqlite3MallocFailed() && pRight->z && pLeft->z ){
    assert( pLeft->dyn==0 || pLeft->z[pLeft->n]==0 );
    if( pLeft->dyn==0 && pRight->dyn==0 ){
      pExpr->span.z = pLeft->z;
      pExpr->span.n = pRight->n + (pRight->z - pLeft->z);
    }else{
      pExpr->span.z = 0;
    }
................................................................................
  }
}

/*
** Construct a new expression node for a function with multiple
** arguments.
*/
Expr *sqlite3ExprFunction(ExprList *pList, Token *pToken){
  Expr *pNew;
  assert( pToken );
  pNew = sqliteMalloc( sizeof(Expr) );
  if( pNew==0 ){
    sqlite3ExprListDelete(pList); /* Avoid leaking memory when malloc fails */
    return 0;
  }
  pNew->op = TK_FUNCTION;
  pNew->pList = pList;
  assert( pToken->dyn==0 );
................................................................................
** Wildcards of the form ":aaa" or "$aaa" are assigned the same number
** as the previous instance of the same wildcard.  Or if this is the first
** instance of the wildcard, the next sequenial variable number is
** assigned.
*/
void sqlite3ExprAssignVarNumber(Parse *pParse, Expr *pExpr){
  Token *pToken;


  if( pExpr==0 ) return;
  pToken = &pExpr->token;
  assert( pToken->n>=1 );
  assert( pToken->z!=0 );
  assert( pToken->z[0]!=0 );
  if( pToken->n==1 ){
    /* Wildcard of the form "?".  Assign the next variable number */
................................................................................
        break;
      }
    }
    if( i>=pParse->nVarExpr ){
      pExpr->iTable = ++pParse->nVar;
      if( pParse->nVarExpr>=pParse->nVarExprAlloc-1 ){
        pParse->nVarExprAlloc += pParse->nVarExprAlloc + 10;
        pParse->apVarExpr = sqliteReallocOrFree(pParse->apVarExpr,



                       pParse->nVarExprAlloc*sizeof(pParse->apVarExpr[0]) );

      }
      if( !sqlite3MallocFailed() ){
        assert( pParse->apVarExpr!=0 );
        pParse->apVarExpr[pParse->nVarExpr++] = pExpr;
      }
    }
  } 
  if( !pParse->nErr && pParse->nVar>SQLITE_MAX_VARIABLE_NUMBER ){
    sqlite3ErrorMsg(pParse, "too many SQL variables");
................................................................................
}

/*
** Recursively delete an expression tree.
*/
void sqlite3ExprDelete(Expr *p){
  if( p==0 ) return;
  if( p->span.dyn ) sqliteFree((char*)p->span.z);
  if( p->token.dyn ) sqliteFree((char*)p->token.z);
  sqlite3ExprDelete(p->pLeft);
  sqlite3ExprDelete(p->pRight);
  sqlite3ExprListDelete(p->pList);
  sqlite3SelectDelete(p->pSelect);
  sqliteFree(p);
}

/*
** The Expr.token field might be a string literal that is quoted.
** If so, remove the quotation marks.
*/
void sqlite3DequoteExpr(Expr *p){
  if( ExprHasAnyProperty(p, EP_Dequoted) ){
    return;
  }
  ExprSetProperty(p, EP_Dequoted);
  if( p->token.dyn==0 ){
    sqlite3TokenCopy(&p->token, &p->token);
  }
  sqlite3Dequote((char*)p->token.z);
}


/*
** The following group of routines make deep copies of expressions,
................................................................................
**
** The expression list, ID, and source lists return by sqlite3ExprListDup(),
** sqlite3IdListDup(), and sqlite3SrcListDup() can not be further expanded 
** by subsequent calls to sqlite*ListAppend() routines.
**
** Any tables that the SrcList might point to are not duplicated.
*/
Expr *sqlite3ExprDup(Expr *p){
  Expr *pNew;
  if( p==0 ) return 0;
  pNew = sqliteMallocRaw( sizeof(*p) );
  if( pNew==0 ) return 0;
  memcpy(pNew, p, sizeof(*pNew));
  if( p->token.z!=0 ){
    pNew->token.z = (u8*)sqliteStrNDup((char*)p->token.z, p->token.n);
    pNew->token.dyn = 1;
  }else{
    assert( pNew->token.z==0 );
  }
  pNew->span.z = 0;
  pNew->pLeft = sqlite3ExprDup(p->pLeft);
  pNew->pRight = sqlite3ExprDup(p->pRight);
  pNew->pList = sqlite3ExprListDup(p->pList);
  pNew->pSelect = sqlite3SelectDup(p->pSelect);
  return pNew;
}
void sqlite3TokenCopy(Token *pTo, Token *pFrom){
  if( pTo->dyn ) sqliteFree((char*)pTo->z);
  if( pFrom->z ){
    pTo->n = pFrom->n;
    pTo->z = (u8*)sqliteStrNDup((char*)pFrom->z, pFrom->n);
    pTo->dyn = 1;
  }else{
    pTo->z = 0;
  }
}
ExprList *sqlite3ExprListDup(ExprList *p){
  ExprList *pNew;
  struct ExprList_item *pItem, *pOldItem;
  int i;
  if( p==0 ) return 0;
  pNew = sqliteMalloc( sizeof(*pNew) );
  if( pNew==0 ) return 0;
  pNew->nExpr = pNew->nAlloc = p->nExpr;
  pNew->a = pItem = sqliteMalloc( p->nExpr*sizeof(p->a[0]) );
  if( pItem==0 ){
    sqliteFree(pNew);
    return 0;
  } 
  pOldItem = p->a;
  for(i=0; i<p->nExpr; i++, pItem++, pOldItem++){
    Expr *pNewExpr, *pOldExpr;
    pItem->pExpr = pNewExpr = sqlite3ExprDup(pOldExpr = pOldItem->pExpr);
    if( pOldExpr->span.z!=0 && pNewExpr ){
      /* Always make a copy of the span for top-level expressions in the
      ** expression list.  The logic in SELECT processing that determines
      ** the names of columns in the result set needs this information */
      sqlite3TokenCopy(&pNewExpr->span, &pOldExpr->span);
    }
    assert( pNewExpr==0 || pNewExpr->span.z!=0 
            || pOldExpr->span.z==0
            || sqlite3MallocFailed() );
    pItem->zName = sqliteStrDup(pOldItem->zName);
    pItem->sortOrder = pOldItem->sortOrder;
    pItem->isAgg = pOldItem->isAgg;
    pItem->done = 0;
  }
  return pNew;
}

................................................................................
** If cursors, triggers, views and subqueries are all omitted from
** the build, then none of the following routines, except for 
** sqlite3SelectDup(), can be called. sqlite3SelectDup() is sometimes
** called with a NULL argument.
*/
#if !defined(SQLITE_OMIT_VIEW) || !defined(SQLITE_OMIT_TRIGGER) \
 || !defined(SQLITE_OMIT_SUBQUERY)
SrcList *sqlite3SrcListDup(SrcList *p){
  SrcList *pNew;
  int i;
  int nByte;
  if( p==0 ) return 0;
  nByte = sizeof(*p) + (p->nSrc>0 ? sizeof(p->a[0]) * (p->nSrc-1) : 0);
  pNew = sqliteMallocRaw( nByte );
  if( pNew==0 ) return 0;
  pNew->nSrc = pNew->nAlloc = p->nSrc;
  for(i=0; i<p->nSrc; i++){
    struct SrcList_item *pNewItem = &pNew->a[i];
    struct SrcList_item *pOldItem = &p->a[i];
    Table *pTab;
    pNewItem->zDatabase = sqliteStrDup(pOldItem->zDatabase);
    pNewItem->zName = sqliteStrDup(pOldItem->zName);
    pNewItem->zAlias = sqliteStrDup(pOldItem->zAlias);
    pNewItem->jointype = pOldItem->jointype;
    pNewItem->iCursor = pOldItem->iCursor;
    pNewItem->isPopulated = pOldItem->isPopulated;
    pTab = pNewItem->pTab = pOldItem->pTab;
    if( pTab ){
      pTab->nRef++;
    }
    pNewItem->pSelect = sqlite3SelectDup(pOldItem->pSelect);
    pNewItem->pOn = sqlite3ExprDup(pOldItem->pOn);
    pNewItem->pUsing = sqlite3IdListDup(pOldItem->pUsing);
    pNewItem->colUsed = pOldItem->colUsed;
  }
  return pNew;
}
IdList *sqlite3IdListDup(IdList *p){
  IdList *pNew;
  int i;
  if( p==0 ) return 0;
  pNew = sqliteMallocRaw( sizeof(*pNew) );
  if( pNew==0 ) return 0;
  pNew->nId = pNew->nAlloc = p->nId;
  pNew->a = sqliteMallocRaw( p->nId*sizeof(p->a[0]) );
  if( pNew->a==0 ){
    sqliteFree(pNew);
    return 0;
  }
  for(i=0; i<p->nId; i++){
    struct IdList_item *pNewItem = &pNew->a[i];
    struct IdList_item *pOldItem = &p->a[i];
    pNewItem->zName = sqliteStrDup(pOldItem->zName);
    pNewItem->idx = pOldItem->idx;
  }
  return pNew;
}
Select *sqlite3SelectDup(Select *p){
  Select *pNew;
  if( p==0 ) return 0;
  pNew = sqliteMallocRaw( sizeof(*p) );
  if( pNew==0 ) return 0;
  pNew->isDistinct = p->isDistinct;
  pNew->pEList = sqlite3ExprListDup(p->pEList);
  pNew->pSrc = sqlite3SrcListDup(p->pSrc);
  pNew->pWhere = sqlite3ExprDup(p->pWhere);
  pNew->pGroupBy = sqlite3ExprListDup(p->pGroupBy);
  pNew->pHaving = sqlite3ExprDup(p->pHaving);
  pNew->pOrderBy = sqlite3ExprListDup(p->pOrderBy);
  pNew->op = p->op;
  pNew->pPrior = sqlite3SelectDup(p->pPrior);
  pNew->pLimit = sqlite3ExprDup(p->pLimit);
  pNew->pOffset = sqlite3ExprDup(p->pOffset);
  pNew->iLimit = -1;
  pNew->iOffset = -1;
  pNew->isResolved = p->isResolved;
  pNew->isAgg = p->isAgg;
  pNew->usesEphm = 0;
  pNew->disallowOrderBy = 0;
  pNew->pRightmost = 0;
  pNew->addrOpenEphm[0] = -1;
  pNew->addrOpenEphm[1] = -1;
  pNew->addrOpenEphm[2] = -1;
  return pNew;
}
#else
Select *sqlite3SelectDup(Select *p){
  assert( p==0 );
  return 0;
}
#endif


/*
** Add a new element to the end of an expression list.  If pList is
** initially NULL, then create a new expression list.
*/
ExprList *sqlite3ExprListAppend(ExprList *pList, Expr *pExpr, Token *pName){






  if( pList==0 ){
    pList = sqliteMalloc( sizeof(ExprList) );
    if( pList==0 ){
      goto no_mem;
    }
    assert( pList->nAlloc==0 );
  }
  if( pList->nAlloc<=pList->nExpr ){
    struct ExprList_item *a;
    int n = pList->nAlloc*2 + 4;
    a = sqliteRealloc(pList->a, n*sizeof(pList->a[0]));
    if( a==0 ){
      goto no_mem;
    }
    pList->a = a;
    pList->nAlloc = n;
  }
  assert( pList->a!=0 );
  if( pExpr || pName ){
    struct ExprList_item *pItem = &pList->a[pList->nExpr++];
    memset(pItem, 0, sizeof(*pItem));
    pItem->zName = sqlite3NameFromToken(pName);
    pItem->pExpr = pExpr;
  }
  return pList;

no_mem:     
  /* Avoid leaking memory if malloc has failed. */

  sqlite3ExprDelete(pExpr);
  sqlite3ExprListDelete(pList);
  return 0;
}

/*
** If the expression list pEList contains more than iLimit elements,
................................................................................
  int i;
  struct ExprList_item *pItem;
  if( pList==0 ) return;
  assert( pList->a!=0 || (pList->nExpr==0 && pList->nAlloc==0) );
  assert( pList->nExpr<=pList->nAlloc );
  for(pItem=pList->a, i=0; i<pList->nExpr; i++, pItem++){
    sqlite3ExprDelete(pItem->pExpr);
    sqliteFree(pItem->zName);
  }
  sqliteFree(pList->a);
  sqliteFree(pList);
}

/*
** Walk an expression tree.  Call xFunc for each node visited.
**
** The return value from xFunc determines whether the tree walk continues.
** 0 means continue walking the tree.  1 means do not walk children
................................................................................
  int cntTab = 0;      /* Number of matching table names */
  sqlite3 *db = pParse->db;  /* The database */
  struct SrcList_item *pItem;       /* Use for looping over pSrcList items */
  struct SrcList_item *pMatch = 0;  /* The matching pSrcList item */
  NameContext *pTopNC = pNC;        /* First namecontext in the list */

  assert( pColumnToken && pColumnToken->z ); /* The Z in X.Y.Z cannot be NULL */
  zDb = sqlite3NameFromToken(pDbToken);
  zTab = sqlite3NameFromToken(pTableToken);
  zCol = sqlite3NameFromToken(pColumnToken);
  if( sqlite3MallocFailed() ){
    goto lookupname_end;
  }

  pExpr->iTable = -1;
  while( pNC && cnt==0 ){
    ExprList *pEList;
    SrcList *pSrcList = pNC->pSrcList;
................................................................................
          Expr *pDup, *pOrig;
          assert( pExpr->pLeft==0 && pExpr->pRight==0 );
          assert( pExpr->pList==0 );
          assert( pExpr->pSelect==0 );
          pOrig = pEList->a[j].pExpr;
          if( !pNC->allowAgg && ExprHasProperty(pOrig, EP_Agg) ){
            sqlite3ErrorMsg(pParse, "misuse of aliased aggregate %s", zAs);
            sqliteFree(zCol);
            return 2;
          }
          pDup = sqlite3ExprDup(pOrig);
          if( pExpr->flags & EP_ExpCollate ){
            pDup->pColl = pExpr->pColl;
            pDup->flags |= EP_ExpCollate;
          }
          if( pExpr->span.dyn ) sqliteFree((char*)pExpr->span.z);
          if( pExpr->token.dyn ) sqliteFree((char*)pExpr->token.z);
          memcpy(pExpr, pDup, sizeof(*pExpr));
          sqliteFree(pDup);
          cnt = 1;
          pMatch = 0;
          assert( zTab==0 && zDb==0 );
          goto lookupname_end_2;
        }
      } 
    }
................................................................................
  ** case, we need to return right away and not make any changes to
  ** pExpr.
  **
  ** Because no reference was made to outer contexts, the pNC->nRef
  ** fields are not changed in any context.
  */
  if( cnt==0 && zTab==0 && pColumnToken->z[0]=='"' ){
    sqliteFree(zCol);
    return 0;
  }

  /*
  ** cnt==0 means there was not match.  cnt>1 means there were two or
  ** more matches.  Either way, we have an error.
  */
................................................................................
    char *zErr;
    zErr = cnt==0 ? "no such column: %s" : "ambiguous column name: %s";
    if( zDb ){
      sqlite3SetString(&z, zDb, ".", zTab, ".", zCol, (char*)0);
    }else if( zTab ){
      sqlite3SetString(&z, zTab, ".", zCol, (char*)0);
    }else{
      z = sqliteStrDup(zCol);
    }
    sqlite3ErrorMsg(pParse, zErr, z);
    sqliteFree(z);
    pTopNC->nErr++;
  }

  /* If a column from a table in pSrcList is referenced, then record
  ** this fact in the pSrcList.a[].colUsed bitmask.  Column 0 causes
  ** bit 0 to be set.  Column 1 sets bit 1.  And so forth.  If the
  ** column number is greater than the number of bits in the bitmask
................................................................................
    assert( pMatch->iCursor==pExpr->iTable );
    pMatch->colUsed |= ((Bitmask)1)<<n;
  }

lookupname_end:
  /* Clean up and return
  */
  sqliteFree(zDb);
  sqliteFree(zTab);
  sqlite3ExprDelete(pExpr->pLeft);
  pExpr->pLeft = 0;
  sqlite3ExprDelete(pExpr->pRight);
  pExpr->pRight = 0;
  pExpr->op = TK_COLUMN;
lookupname_end_2:
  sqliteFree(zCol);
  if( cnt==1 ){
    assert( pNC!=0 );
    sqlite3AuthRead(pParse, pExpr, pNC->pSrcList);
    if( pMatch && !pMatch->pSelect ){
      pExpr->pTab = pMatch->pTab;
    }
    /* Increment the nRef value on all name contexts from TopNC up to
................................................................................
  ** If all of the above are false, then we can run this code just once
  ** save the results, and reuse the same result on subsequent invocations.
  */
  if( !ExprHasAnyProperty(pExpr, EP_VarSelect) && !pParse->trigStack ){
    int mem = pParse->nMem++;
    sqlite3VdbeAddOp(v, OP_MemLoad, mem, 0);
    testAddr = sqlite3VdbeAddOp(v, OP_If, 0, 0);
    assert( testAddr>0 || sqlite3MallocFailed() );
    sqlite3VdbeAddOp(v, OP_MemInt, 1, mem);
  }

  switch( pExpr->op ){
    case TK_IN: {
      char affinity;
      KeyInfo keyInfo;
................................................................................
#endif /* SQLITE_OMIT_SUBQUERY */

/*
** Generate an instruction that will put the integer describe by
** text z[0..n-1] on the stack.
*/
static void codeInteger(Vdbe *v, const char *z, int n){
  assert( z || sqlite3MallocFailed() );
  if( z ){
    int i;
    if( sqlite3GetInt32(z, &i) ){
      sqlite3VdbeAddOp(v, OP_Integer, i, 0);
    }else if( sqlite3FitsIn64Bits(z) ){
      sqlite3VdbeOp3(v, OP_Int64, 0, 0, z, n);
    }else{
................................................................................
        Token *p = &pLeft->token;
        char *z = sqlite3MPrintf("-%.*s", p->n, p->z);
        if( pLeft->op==TK_FLOAT ){
          sqlite3VdbeOp3(v, OP_Real, 0, 0, z, p->n+1);
        }else{
          codeInteger(v, z, p->n+1);
        }
        sqliteFree(z);
        break;
      }
      /* Fall through into TK_NOT */
    }
    case TK_BITNOT:
    case TK_NOT: {
      assert( TK_BITNOT==OP_BitNot );
................................................................................
      ExprList *pList = pExpr->pList;
      int nExpr = pList ? pList->nExpr : 0;
      FuncDef *pDef;
      int nId;
      const char *zId;
      int constMask = 0;
      int i;

      u8 enc = ENC(pParse->db);
      CollSeq *pColl = 0;

      zId = (char*)pExpr->token.z;
      nId = pExpr->token.n;
      pDef = sqlite3FindFunction(pParse->db, zId, nId, nExpr, enc, 0);
      assert( pDef!=0 );
      nExpr = sqlite3ExprCodeExprList(pParse, pList);
#ifndef SQLITE_OMIT_VIRTUALTABLE
      /* Possibly overload the function if the first argument is
................................................................................
      ** the left operand of infix functions (the operand we want to
      ** control overloading) ends up as the second argument to the
      ** function.  The expression "A glob B" is equivalent to 
      ** "glob(B,A).  We want to use the A in "A glob B" to test
      ** for function overloading.  But we use the B term in "glob(B,A)".
      */
      if( nExpr>=2 && (pExpr->flags & EP_InfixFunc) ){
        pDef = sqlite3VtabOverloadFunction(pDef, nExpr, pList->a[1].pExpr);
      }else if( nExpr>0 ){
        pDef = sqlite3VtabOverloadFunction(pDef, nExpr, pList->a[0].pExpr);
      }
#endif
      for(i=0; i<nExpr && i<32; i++){
        if( sqlite3ExprIsConstant(pList->a[i].pExpr) ){
          constMask |= (1<<i);
        }
        if( pDef->needCollSeq && !pColl ){
................................................................................
}


/*
** Add a new element to the pAggInfo->aCol[] array.  Return the index of
** the new element.  Return a negative number if malloc fails.
*/
static int addAggInfoColumn(AggInfo *pInfo){
  int i;
  pInfo->aCol = sqlite3ArrayAllocate(

       pInfo->aCol,
       sizeof(pInfo->aCol[0]),
       3,
       &pInfo->nColumn,
       &pInfo->nColumnAlloc,
       &i
  );
................................................................................
  return i;
}    

/*
** Add a new element to the pAggInfo->aFunc[] array.  Return the index of
** the new element.  Return a negative number if malloc fails.
*/
static int addAggInfoFunc(AggInfo *pInfo){
  int i;
  pInfo->aFunc = sqlite3ArrayAllocate(

       pInfo->aFunc,
       sizeof(pInfo->aFunc[0]),
       3,
       &pInfo->nFunc,
       &pInfo->nFuncAlloc,
       &i
  );

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains routines used for analyzing expressions and
** for generating VDBE code that evaluates expressions in SQLite.
**
** $Id: expr.c,v 1.304 2007/08/16 04:30:40 drh Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>

/*
** Return the 'affinity' of the expression pExpr if any.
**
................................................................................
  int p1 = binaryCompareP1(pLeft, pRight, jumpIfNull);
  CollSeq *p3 = sqlite3BinaryCompareCollSeq(pParse, pLeft, pRight);
  return sqlite3VdbeOp3(pParse->pVdbe, opcode, p1, dest, (void*)p3, P3_COLLSEQ);
}

/*
** Construct a new expression node and return a pointer to it.  Memory
** for this node is obtained from sqlite3_malloc().  The calling function
** is responsible for making sure the node eventually gets freed.
*/
Expr *sqlite3Expr(
  int op,                 /* Expression opcode */
  Expr *pLeft,            /* Left operand */
  Expr *pRight,           /* Right operand */
  const Token *pToken     /* Argument token */
){
  Expr *pNew;
  pNew = sqlite3MallocZero( sizeof(Expr) );
  if( pNew==0 ){
    /* When malloc fails, delete pLeft and pRight. Expressions passed to 
    ** this function must always be allocated with sqlite3Expr() for this 
    ** reason. 
    */
    sqlite3ExprDelete(pLeft);
    sqlite3ExprDelete(pRight);
................................................................................
  }

  sqlite3ExprSetHeight(pNew);
  return pNew;
}

/*
** Works like sqlite3Expr() except that it takes an extra Parse*
** argument and notifies the associated connection object if malloc fails.
*/
Expr *sqlite3PExpr(
  Parse *pParse,          /* Parsing context */
  int op,                 /* Expression opcode */
  Expr *pLeft,            /* Left operand */
  Expr *pRight,           /* Right operand */
  const Token *pToken     /* Argument token */
){
  Expr *pNew = sqlite3Expr(op, pLeft, pRight, pToken);
  if( pNew==0 ){
    sqlite3ExprDelete(pLeft);
    sqlite3ExprDelete(pRight);
    pParse->db->mallocFailed = 1;
  }
  return pNew;
}

/*
** When doing a nested parse, you can include terms in an expression
** that look like this:   #0 #1 #2 ...  These terms refer to elements
................................................................................
  if( pParse->nested==0 ){
    sqlite3ErrorMsg(pParse, "near \"%T\": syntax error", pToken);
    return sqlite3Expr(TK_NULL, 0, 0, 0);
  }
  if( v==0 ) return 0;
  p = sqlite3Expr(TK_REGISTER, 0, 0, pToken);
  if( p==0 ){
    pParse->db->mallocFailed = 1;
    return 0;  /* Malloc failed */
  }
  depth = atoi((char*)&pToken->z[1]);
  p->iTable = pParse->nMem++;
  sqlite3VdbeAddOp(v, OP_Dup, depth, 0);
  sqlite3VdbeAddOp(v, OP_MemStore, p->iTable, 1);
  return p;
}

/*
** Join two expressions using an AND operator.  If either expression is
** NULL, then just return the other expression.
*/
Expr *sqlite3ExprAnd(sqlite *db, Expr *pLeft, Expr *pRight){
  if( pLeft==0 ){
    return pRight;
  }else if( pRight==0 ){
    return pLeft;
  }else{
    Expr *p = sqlite3Expr(TK_AND, pLeft, pRight, 0);
    if( p==0 ){
      db->mallocFailed = 1;
    }
  }
}

/*
** Set the Expr.span field of the given expression to span all
** text between the two given tokens.
*/
void sqlite3ExprSpan(Expr *pExpr, Token *pLeft, Token *pRight){
  assert( pRight!=0 );
  assert( pLeft!=0 );
  if( pRight->z && pLeft->z ){
    assert( pLeft->dyn==0 || pLeft->z[pLeft->n]==0 );
    if( pLeft->dyn==0 && pRight->dyn==0 ){
      pExpr->span.z = pLeft->z;
      pExpr->span.n = pRight->n + (pRight->z - pLeft->z);
    }else{
      pExpr->span.z = 0;
    }
................................................................................
  }
}

/*
** Construct a new expression node for a function with multiple
** arguments.
*/
Expr *sqlite3ExprFunction(Parse *pParse, ExprList *pList, Token *pToken){
  Expr *pNew;
  assert( pToken );
  pNew = sqlite3DbMallocZero(pParse->db, sizeof(Expr) );
  if( pNew==0 ){
    sqlite3ExprListDelete(pList); /* Avoid leaking memory when malloc fails */
    return 0;
  }
  pNew->op = TK_FUNCTION;
  pNew->pList = pList;
  assert( pToken->dyn==0 );
................................................................................
** Wildcards of the form ":aaa" or "$aaa" are assigned the same number
** as the previous instance of the same wildcard.  Or if this is the first
** instance of the wildcard, the next sequenial variable number is
** assigned.
*/
void sqlite3ExprAssignVarNumber(Parse *pParse, Expr *pExpr){
  Token *pToken;
  sqlite3 *db = pParse->db;

  if( pExpr==0 ) return;
  pToken = &pExpr->token;
  assert( pToken->n>=1 );
  assert( pToken->z!=0 );
  assert( pToken->z[0]!=0 );
  if( pToken->n==1 ){
    /* Wildcard of the form "?".  Assign the next variable number */
................................................................................
        break;
      }
    }
    if( i>=pParse->nVarExpr ){
      pExpr->iTable = ++pParse->nVar;
      if( pParse->nVarExpr>=pParse->nVarExprAlloc-1 ){
        pParse->nVarExprAlloc += pParse->nVarExprAlloc + 10;
        pParse->apVarExpr =
            sqlite3DbReallocOrFree(
              db,
              pParse->apVarExpr,
              pParse->nVarExprAlloc*sizeof(pParse->apVarExpr[0])
            );
      }
      if( !db->mallocFailed ){
        assert( pParse->apVarExpr!=0 );
        pParse->apVarExpr[pParse->nVarExpr++] = pExpr;
      }
    }
  } 
  if( !pParse->nErr && pParse->nVar>SQLITE_MAX_VARIABLE_NUMBER ){
    sqlite3ErrorMsg(pParse, "too many SQL variables");
................................................................................
}

/*
** Recursively delete an expression tree.
*/
void sqlite3ExprDelete(Expr *p){
  if( p==0 ) return;
  if( p->span.dyn ) sqlite3_free((char*)p->span.z);
  if( p->token.dyn ) sqlite3_free((char*)p->token.z);
  sqlite3ExprDelete(p->pLeft);
  sqlite3ExprDelete(p->pRight);
  sqlite3ExprListDelete(p->pList);
  sqlite3SelectDelete(p->pSelect);
  sqlite3_free(p);
}

/*
** The Expr.token field might be a string literal that is quoted.
** If so, remove the quotation marks.
*/
void sqlite3DequoteExpr(sqlite3 *db, Expr *p){
  if( ExprHasAnyProperty(p, EP_Dequoted) ){
    return;
  }
  ExprSetProperty(p, EP_Dequoted);
  if( p->token.dyn==0 ){
    sqlite3TokenCopy(db, &p->token, &p->token);
  }
  sqlite3Dequote((char*)p->token.z);
}


/*
** The following group of routines make deep copies of expressions,
................................................................................
**
** The expression list, ID, and source lists return by sqlite3ExprListDup(),
** sqlite3IdListDup(), and sqlite3SrcListDup() can not be further expanded 
** by subsequent calls to sqlite*ListAppend() routines.
**
** Any tables that the SrcList might point to are not duplicated.
*/
Expr *sqlite3ExprDup(sqlite *db, Expr *p){
  Expr *pNew;
  if( p==0 ) return 0;
  pNew = sqlite3DbMallocRaw(db, sizeof(*p) );
  if( pNew==0 ) return 0;
  memcpy(pNew, p, sizeof(*pNew));
  if( p->token.z!=0 ){
    pNew->token.z = (u8*)sqlite3DbStrNDup(db, (char*)p->token.z, p->token.n);
    pNew->token.dyn = 1;
  }else{
    assert( pNew->token.z==0 );
  }
  pNew->span.z = 0;
  pNew->pLeft = sqlite3ExprDup(db, p->pLeft);
  pNew->pRight = sqlite3ExprDup(db, p->pRight);
  pNew->pList = sqlite3ExprListDup(db, p->pList);
  pNew->pSelect = sqlite3SelectDup(db, p->pSelect);
  return pNew;
}
void sqlite3TokenCopy(sqlite3 *db, Token *pTo, Token *pFrom){
  if( pTo->dyn ) sqlite3_free((char*)pTo->z);
  if( pFrom->z ){
    pTo->n = pFrom->n;
    pTo->z = (u8*)sqlite3DbStrNDup(db, (char*)pFrom->z, pFrom->n);
    pTo->dyn = 1;
  }else{
    pTo->z = 0;
  }
}
ExprList *sqlite3ExprListDup(sqlite3 *db, ExprList *p){
  ExprList *pNew;
  struct ExprList_item *pItem, *pOldItem;
  int i;
  if( p==0 ) return 0;
  pNew = sqlite3DbMallocRaw(db, sizeof(*pNew) );
  if( pNew==0 ) return 0;
  pNew->nExpr = pNew->nAlloc = p->nExpr;
  pNew->a = pItem = sqlite3DbMallocRaw(db,  p->nExpr*sizeof(p->a[0]) );
  if( pItem==0 ){
    sqlite3_free(pNew);
    return 0;
  } 
  pOldItem = p->a;
  for(i=0; i<p->nExpr; i++, pItem++, pOldItem++){
    Expr *pNewExpr, *pOldExpr;
    pItem->pExpr = pNewExpr = sqlite3ExprDup(db, pOldExpr = pOldItem->pExpr);
    if( pOldExpr->span.z!=0 && pNewExpr ){
      /* Always make a copy of the span for top-level expressions in the
      ** expression list.  The logic in SELECT processing that determines
      ** the names of columns in the result set needs this information */
      sqlite3TokenCopy(db, &pNewExpr->span, &pOldExpr->span);
    }
    assert( pNewExpr==0 || pNewExpr->span.z!=0 
            || pOldExpr->span.z==0
            || db->mallocFailed );
    pItem->zName = sqlite3DbStrDup(db, pOldItem->zName);
    pItem->sortOrder = pOldItem->sortOrder;
    pItem->isAgg = pOldItem->isAgg;
    pItem->done = 0;
  }
  return pNew;
}

................................................................................
** If cursors, triggers, views and subqueries are all omitted from
** the build, then none of the following routines, except for 
** sqlite3SelectDup(), can be called. sqlite3SelectDup() is sometimes
** called with a NULL argument.
*/
#if !defined(SQLITE_OMIT_VIEW) || !defined(SQLITE_OMIT_TRIGGER) \
 || !defined(SQLITE_OMIT_SUBQUERY)
SrcList *sqlite3SrcListDup(sqlite3 *db, SrcList *p){
  SrcList *pNew;
  int i;
  int nByte;
  if( p==0 ) return 0;
  nByte = sizeof(*p) + (p->nSrc>0 ? sizeof(p->a[0]) * (p->nSrc-1) : 0);
  pNew = sqlite3DbMallocRaw(db, nByte );
  if( pNew==0 ) return 0;
  pNew->nSrc = pNew->nAlloc = p->nSrc;
  for(i=0; i<p->nSrc; i++){
    struct SrcList_item *pNewItem = &pNew->a[i];
    struct SrcList_item *pOldItem = &p->a[i];
    Table *pTab;
    pNewItem->zDatabase = sqlite3DbStrDup(db, pOldItem->zDatabase);
    pNewItem->zName = sqlite3DbStrDup(db, pOldItem->zName);
    pNewItem->zAlias = sqlite3DbStrDup(db, pOldItem->zAlias);
    pNewItem->jointype = pOldItem->jointype;
    pNewItem->iCursor = pOldItem->iCursor;
    pNewItem->isPopulated = pOldItem->isPopulated;
    pTab = pNewItem->pTab = pOldItem->pTab;
    if( pTab ){
      pTab->nRef++;
    }
    pNewItem->pSelect = sqlite3SelectDup(db, pOldItem->pSelect);
    pNewItem->pOn = sqlite3ExprDup(db, pOldItem->pOn);
    pNewItem->pUsing = sqlite3IdListDup(db, pOldItem->pUsing);
    pNewItem->colUsed = pOldItem->colUsed;
  }
  return pNew;
}
IdList *sqlite3IdListDup(sqlite3 *db, IdList *p){
  IdList *pNew;
  int i;
  if( p==0 ) return 0;
  pNew = sqlite3DbMallocRaw(db, sizeof(*pNew) );
  if( pNew==0 ) return 0;
  pNew->nId = pNew->nAlloc = p->nId;
  pNew->a = sqlite3DbMallocRaw(db, p->nId*sizeof(p->a[0]) );
  if( pNew->a==0 ){
    sqlite3_free(pNew);
    return 0;
  }
  for(i=0; i<p->nId; i++){
    struct IdList_item *pNewItem = &pNew->a[i];
    struct IdList_item *pOldItem = &p->a[i];
    pNewItem->zName = sqlite3DbStrDup(db, pOldItem->zName);
    pNewItem->idx = pOldItem->idx;
  }
  return pNew;
}
Select *sqlite3SelectDup(sqlite3 *db, Select *p){
  Select *pNew;
  if( p==0 ) return 0;
  pNew = sqlite3DbMallocRaw(db, sizeof(*p) );
  if( pNew==0 ) return 0;
  pNew->isDistinct = p->isDistinct;
  pNew->pEList = sqlite3ExprListDup(db, p->pEList);
  pNew->pSrc = sqlite3SrcListDup(db, p->pSrc);
  pNew->pWhere = sqlite3ExprDup(db, p->pWhere);
  pNew->pGroupBy = sqlite3ExprListDup(db, p->pGroupBy);
  pNew->pHaving = sqlite3ExprDup(db, p->pHaving);
  pNew->pOrderBy = sqlite3ExprListDup(db, p->pOrderBy);
  pNew->op = p->op;
  pNew->pPrior = sqlite3SelectDup(db, p->pPrior);
  pNew->pLimit = sqlite3ExprDup(db, p->pLimit);
  pNew->pOffset = sqlite3ExprDup(db, p->pOffset);
  pNew->iLimit = -1;
  pNew->iOffset = -1;
  pNew->isResolved = p->isResolved;
  pNew->isAgg = p->isAgg;
  pNew->usesEphm = 0;
  pNew->disallowOrderBy = 0;
  pNew->pRightmost = 0;
  pNew->addrOpenEphm[0] = -1;
  pNew->addrOpenEphm[1] = -1;
  pNew->addrOpenEphm[2] = -1;
  return pNew;
}
#else
Select *sqlite3SelectDup(sqlite3 *db, Select *p){
  assert( p==0 );
  return 0;
}
#endif


/*
** Add a new element to the end of an expression list.  If pList is
** initially NULL, then create a new expression list.
*/
ExprList *sqlite3ExprListAppend(
  Parse *pParse,          /* Parsing context */
  ExprList *pList,        /* List to which to append. Might be NULL */
  Expr *pExpr,            /* Expression to be appended */
  Token *pName            /* AS keyword for the expression */
){
  sqlite3 *db = pParse->db;
  if( pList==0 ){
    pList = sqlite3DbMallocZero(db, sizeof(ExprList) );
    if( pList==0 ){
      goto no_mem;
    }
    assert( pList->nAlloc==0 );
  }
  if( pList->nAlloc<=pList->nExpr ){
    struct ExprList_item *a;
    int n = pList->nAlloc*2 + 4;
    a = sqlite3_realloc(pList->a, n*sizeof(pList->a[0]));
    if( a==0 ){
      goto no_mem;
    }
    pList->a = a;
    pList->nAlloc = n;
  }
  assert( pList->a!=0 );
  if( pExpr || pName ){
    struct ExprList_item *pItem = &pList->a[pList->nExpr++];
    memset(pItem, 0, sizeof(*pItem));
    pItem->zName = sqlite3NameFromToken(db, pName);
    pItem->pExpr = pExpr;
  }
  return pList;

no_mem:     
  /* Avoid leaking memory if malloc has failed. */
  db->mallocFailed = 1;
  sqlite3ExprDelete(pExpr);
  sqlite3ExprListDelete(pList);
  return 0;
}

/*
** If the expression list pEList contains more than iLimit elements,
................................................................................
  int i;
  struct ExprList_item *pItem;
  if( pList==0 ) return;
  assert( pList->a!=0 || (pList->nExpr==0 && pList->nAlloc==0) );
  assert( pList->nExpr<=pList->nAlloc );
  for(pItem=pList->a, i=0; i<pList->nExpr; i++, pItem++){
    sqlite3ExprDelete(pItem->pExpr);
    sqlite3_free(pItem->zName);
  }
  sqlite3_free(pList->a);
  sqlite3_free(pList);
}

/*
** Walk an expression tree.  Call xFunc for each node visited.
**
** The return value from xFunc determines whether the tree walk continues.
** 0 means continue walking the tree.  1 means do not walk children
................................................................................
  int cntTab = 0;      /* Number of matching table names */
  sqlite3 *db = pParse->db;  /* The database */
  struct SrcList_item *pItem;       /* Use for looping over pSrcList items */
  struct SrcList_item *pMatch = 0;  /* The matching pSrcList item */
  NameContext *pTopNC = pNC;        /* First namecontext in the list */

  assert( pColumnToken && pColumnToken->z ); /* The Z in X.Y.Z cannot be NULL */
  zDb = sqlite3NameFromToken(db, pDbToken);
  zTab = sqlite3NameFromToken(db, pTableToken);
  zCol = sqlite3NameFromToken(db, pColumnToken);
  if( db->mallocFailed ){
    goto lookupname_end;
  }

  pExpr->iTable = -1;
  while( pNC && cnt==0 ){
    ExprList *pEList;
    SrcList *pSrcList = pNC->pSrcList;
................................................................................
          Expr *pDup, *pOrig;
          assert( pExpr->pLeft==0 && pExpr->pRight==0 );
          assert( pExpr->pList==0 );
          assert( pExpr->pSelect==0 );
          pOrig = pEList->a[j].pExpr;
          if( !pNC->allowAgg && ExprHasProperty(pOrig, EP_Agg) ){
            sqlite3ErrorMsg(pParse, "misuse of aliased aggregate %s", zAs);
            sqlite3_free(zCol);
            return 2;
          }
          pDup = sqlite3ExprDup(pOrig);
          if( pExpr->flags & EP_ExpCollate ){
            pDup->pColl = pExpr->pColl;
            pDup->flags |= EP_ExpCollate;
          }
          if( pExpr->span.dyn ) sqlite3_free((char*)pExpr->span.z);
          if( pExpr->token.dyn ) sqlite3_free((char*)pExpr->token.z);
          memcpy(pExpr, pDup, sizeof(*pExpr));
          sqlite3_free(pDup);
          cnt = 1;
          pMatch = 0;
          assert( zTab==0 && zDb==0 );
          goto lookupname_end_2;
        }
      } 
    }
................................................................................
  ** case, we need to return right away and not make any changes to
  ** pExpr.
  **
  ** Because no reference was made to outer contexts, the pNC->nRef
  ** fields are not changed in any context.
  */
  if( cnt==0 && zTab==0 && pColumnToken->z[0]=='"' ){
    sqlite3_free(zCol);
    return 0;
  }

  /*
  ** cnt==0 means there was not match.  cnt>1 means there were two or
  ** more matches.  Either way, we have an error.
  */
................................................................................
    char *zErr;
    zErr = cnt==0 ? "no such column: %s" : "ambiguous column name: %s";
    if( zDb ){
      sqlite3SetString(&z, zDb, ".", zTab, ".", zCol, (char*)0);
    }else if( zTab ){
      sqlite3SetString(&z, zTab, ".", zCol, (char*)0);
    }else{
      z = sqlite3StrDup(zCol);
    }
    sqlite3ErrorMsg(pParse, zErr, z);
    sqlite3_free(z);
    pTopNC->nErr++;
  }

  /* If a column from a table in pSrcList is referenced, then record
  ** this fact in the pSrcList.a[].colUsed bitmask.  Column 0 causes
  ** bit 0 to be set.  Column 1 sets bit 1.  And so forth.  If the
  ** column number is greater than the number of bits in the bitmask
................................................................................
    assert( pMatch->iCursor==pExpr->iTable );
    pMatch->colUsed |= ((Bitmask)1)<<n;
  }

lookupname_end:
  /* Clean up and return
  */
  sqlite3_free(zDb);
  sqlite3_free(zTab);
  sqlite3ExprDelete(pExpr->pLeft);
  pExpr->pLeft = 0;
  sqlite3ExprDelete(pExpr->pRight);
  pExpr->pRight = 0;
  pExpr->op = TK_COLUMN;
lookupname_end_2:
  sqlite3_free(zCol);
  if( cnt==1 ){
    assert( pNC!=0 );
    sqlite3AuthRead(pParse, pExpr, pNC->pSrcList);
    if( pMatch && !pMatch->pSelect ){
      pExpr->pTab = pMatch->pTab;
    }
    /* Increment the nRef value on all name contexts from TopNC up to
................................................................................
  ** If all of the above are false, then we can run this code just once
  ** save the results, and reuse the same result on subsequent invocations.
  */
  if( !ExprHasAnyProperty(pExpr, EP_VarSelect) && !pParse->trigStack ){
    int mem = pParse->nMem++;
    sqlite3VdbeAddOp(v, OP_MemLoad, mem, 0);
    testAddr = sqlite3VdbeAddOp(v, OP_If, 0, 0);
    assert( testAddr>0 || pParse->db->mallocFailed );
    sqlite3VdbeAddOp(v, OP_MemInt, 1, mem);
  }

  switch( pExpr->op ){
    case TK_IN: {
      char affinity;
      KeyInfo keyInfo;
................................................................................
#endif /* SQLITE_OMIT_SUBQUERY */

/*
** Generate an instruction that will put the integer describe by
** text z[0..n-1] on the stack.
*/
static void codeInteger(Vdbe *v, const char *z, int n){
  assert( z || v==0 || sqlite3DbOfVdbe(v)->mallocFailed );
  if( z ){
    int i;
    if( sqlite3GetInt32(z, &i) ){
      sqlite3VdbeAddOp(v, OP_Integer, i, 0);
    }else if( sqlite3FitsIn64Bits(z) ){
      sqlite3VdbeOp3(v, OP_Int64, 0, 0, z, n);
    }else{
................................................................................
        Token *p = &pLeft->token;
        char *z = sqlite3MPrintf("-%.*s", p->n, p->z);
        if( pLeft->op==TK_FLOAT ){
          sqlite3VdbeOp3(v, OP_Real, 0, 0, z, p->n+1);
        }else{
          codeInteger(v, z, p->n+1);
        }
        sqlite3_free(z);
        break;
      }
      /* Fall through into TK_NOT */
    }
    case TK_BITNOT:
    case TK_NOT: {
      assert( TK_BITNOT==OP_BitNot );
................................................................................
      ExprList *pList = pExpr->pList;
      int nExpr = pList ? pList->nExpr : 0;
      FuncDef *pDef;
      int nId;
      const char *zId;
      int constMask = 0;
      int i;
      sqlite3 *db = pParse->db;
      u8 enc = ENC(db);
      CollSeq *pColl = 0;

      zId = (char*)pExpr->token.z;
      nId = pExpr->token.n;
      pDef = sqlite3FindFunction(pParse->db, zId, nId, nExpr, enc, 0);
      assert( pDef!=0 );
      nExpr = sqlite3ExprCodeExprList(pParse, pList);
#ifndef SQLITE_OMIT_VIRTUALTABLE
      /* Possibly overload the function if the first argument is
................................................................................
      ** the left operand of infix functions (the operand we want to
      ** control overloading) ends up as the second argument to the
      ** function.  The expression "A glob B" is equivalent to 
      ** "glob(B,A).  We want to use the A in "A glob B" to test
      ** for function overloading.  But we use the B term in "glob(B,A)".
      */
      if( nExpr>=2 && (pExpr->flags & EP_InfixFunc) ){
        pDef = sqlite3VtabOverloadFunction(db, pDef, nExpr, pList->a[1].pExpr);
      }else if( nExpr>0 ){
        pDef = sqlite3VtabOverloadFunction(db, pDef, nExpr, pList->a[0].pExpr);
      }
#endif
      for(i=0; i<nExpr && i<32; i++){
        if( sqlite3ExprIsConstant(pList->a[i].pExpr) ){
          constMask |= (1<<i);
        }
        if( pDef->needCollSeq && !pColl ){
................................................................................
}


/*
** Add a new element to the pAggInfo->aCol[] array.  Return the index of
** the new element.  Return a negative number if malloc fails.
*/
static int addAggInfoColumn(sqlite3 *db, AggInfo *pInfo){
  int i;
  pInfo->aCol = sqlite3ArrayAllocate(
       db,
       pInfo->aCol,
       sizeof(pInfo->aCol[0]),
       3,
       &pInfo->nColumn,
       &pInfo->nColumnAlloc,
       &i
  );
................................................................................
  return i;
}    

/*
** Add a new element to the pAggInfo->aFunc[] array.  Return the index of
** the new element.  Return a negative number if malloc fails.
*/
static int addAggInfoFunc(sqlite3 *db, AggInfo *pInfo){
  int i;
  pInfo->aFunc = sqlite3ArrayAllocate(
       db, 
       pInfo->aFunc,
       sizeof(pInfo->aFunc[0]),
       3,
       &pInfo->nFunc,
       &pInfo->nFuncAlloc,
       &i
  );

** This file contains the C functions that implement various SQL
** functions of SQLite.  
**
** There is only one exported symbol in this file - the function
** sqliteRegisterBuildinFunctions() found at the bottom of the file.
** All other code has file scope.
**
** $Id: func.c,v 1.163 2007/07/26 06:50:06 danielk1977 Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>
/* #include <math.h> */
#include <stdlib.h>
#include <assert.h>
#include "vdbeInt.h"
................................................................................
  if( n<1 ){
    n = 1;
  }
  if( n>SQLITE_MAX_LENGTH ){
    sqlite3_result_error_toobig(context);
    return;
  }
  p = sqliteMalloc(n);
  if( p ){
    sqlite3Randomness(n, p);
    sqlite3_result_blob(context, (char*)p, n, sqlite3FreeX);
  }
}

/*
** Implementation of the last_insert_rowid() SQL function.  The return
** value is the same as the sqlite3_last_insert_rowid() API function.
*/
................................................................................
      int nBlob = sqlite3_value_bytes(argv[0]);
      assert( zBlob==sqlite3_value_blob(argv[0]) ); /* No encoding change */

      if( 2*nBlob+4>SQLITE_MAX_LENGTH ){
        sqlite3_result_error_toobig(context);
        return;
      }
      zText = (char *)sqliteMalloc((2*nBlob)+4); 
      if( !zText ){
        sqlite3_result_error(context, "out of memory", -1);
      }else{
        int i;
        for(i=0; i<nBlob; i++){
          zText[(i*2)+2] = hexdigits[(zBlob[i]>>4)&0x0F];
          zText[(i*2)+3] = hexdigits[(zBlob[i])&0x0F];
        }
        zText[(nBlob*2)+2] = '\'';
        zText[(nBlob*2)+3] = '\0';
        zText[0] = 'X';
        zText[1] = '\'';
        sqlite3_result_text(context, zText, -1, SQLITE_TRANSIENT);
        sqliteFree(zText);
      }
      break;
    }
    case SQLITE_TEXT: {
      int i,j;
      u64 n;
      const unsigned char *zArg = sqlite3_value_text(argv[0]);
................................................................................

      if( zArg==0 ) return;
      for(i=0, n=0; zArg[i]; i++){ if( zArg[i]=='\'' ) n++; }
      if( i+n+3>SQLITE_MAX_LENGTH ){
        sqlite3_result_error_toobig(context);
        return;
      }
      z = sqliteMalloc( i+n+3 );
      if( z==0 ) return;
      z[0] = '\'';
      for(i=0, j=1; zArg[i]; i++){
        z[j++] = zArg[i];
        if( zArg[i]=='\'' ){
          z[j++] = '\'';
        }
      }
      z[j++] = '\'';
      z[j] = 0;
      sqlite3_result_text(context, z, j, SQLITE_TRANSIENT);
      sqliteFree(z);
    }
  }
}

/*
** The hex() function.  Interpret the argument as a blob.  Return
** a hexadecimal rendering as text.
................................................................................
** WARNING: Not threadsafe.
*/
static int test_destructor_count_var = 0;
static void destructor(void *p){
  char *zVal = (char *)p;
  assert(zVal);
  zVal--;
  sqliteFree(zVal);
  test_destructor_count_var--;
}
static void test_destructor(
  sqlite3_context *pCtx, 
  int nArg,
  sqlite3_value **argv
){
................................................................................
** The test_auxdata() SQL function attempts to register each of its arguments
** as auxiliary data.  If there are no prior registrations of aux data for
** that argument (meaning the argument is not a constant or this is its first
** call) then the result for that argument is 0.  If there is a prior
** registration, the result for that argument is 1.  The overall result
** is the individual argument results separated by spaces.
*/
static void free_test_auxdata(void *p) {sqliteFree(p);}
static void test_auxdata(
  sqlite3_context *pCtx, 
  int nArg,
  sqlite3_value **argv
){
  int i;
  char *zRet = sqliteMalloc(nArg*2);
................................................................................
        if( strcmp(zAux, z) ){
          free_test_auxdata((void *)zRet);
          sqlite3_result_error(pCtx, "Auxilary data corruption", -1);
          return;
        }
      }else{
        zRet[i*2] = '0';
        zAux = sqliteStrDup(z);
        sqlite3_set_auxdata(pCtx, i, zAux, free_test_auxdata);
      }
      zRet[i*2+1] = ' ';
    }
  }
  sqlite3_result_text(pCtx, zRet, 2*nArg-1, free_test_auxdata);
}

** This file contains the C functions that implement various SQL
** functions of SQLite.  
**
** There is only one exported symbol in this file - the function
** sqliteRegisterBuildinFunctions() found at the bottom of the file.
** All other code has file scope.
**
** $Id: func.c,v 1.164 2007/08/16 04:30:40 drh Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>
/* #include <math.h> */
#include <stdlib.h>
#include <assert.h>
#include "vdbeInt.h"
................................................................................
  if( n<1 ){
    n = 1;
  }
  if( n>SQLITE_MAX_LENGTH ){
    sqlite3_result_error_toobig(context);
    return;
  }
  p = sqlite3_malloc(n);
  if( p ){
    sqlite3Randomness(n, p);
    sqlite3_result_blob(context, (char*)p, n, sqlite3_free);
  }
}

/*
** Implementation of the last_insert_rowid() SQL function.  The return
** value is the same as the sqlite3_last_insert_rowid() API function.
*/
................................................................................
      int nBlob = sqlite3_value_bytes(argv[0]);
      assert( zBlob==sqlite3_value_blob(argv[0]) ); /* No encoding change */

      if( 2*nBlob+4>SQLITE_MAX_LENGTH ){
        sqlite3_result_error_toobig(context);
        return;
      }
      zText = (char *)sqlite3_malloc((2*nBlob)+4); 
      if( !zText ){
        sqlite3_result_error(context, "out of memory", -1);
      }else{
        int i;
        for(i=0; i<nBlob; i++){
          zText[(i*2)+2] = hexdigits[(zBlob[i]>>4)&0x0F];
          zText[(i*2)+3] = hexdigits[(zBlob[i])&0x0F];
        }
        zText[(nBlob*2)+2] = '\'';
        zText[(nBlob*2)+3] = '\0';
        zText[0] = 'X';
        zText[1] = '\'';
        sqlite3_result_text(context, zText, -1, SQLITE_TRANSIENT);
        sqlite3_free(zText);
      }
      break;
    }
    case SQLITE_TEXT: {
      int i,j;
      u64 n;
      const unsigned char *zArg = sqlite3_value_text(argv[0]);
................................................................................

      if( zArg==0 ) return;
      for(i=0, n=0; zArg[i]; i++){ if( zArg[i]=='\'' ) n++; }
      if( i+n+3>SQLITE_MAX_LENGTH ){
        sqlite3_result_error_toobig(context);
        return;
      }
      z = sqlite3_malloc( i+n+3 );
      if( z==0 ) return;
      z[0] = '\'';
      for(i=0, j=1; zArg[i]; i++){
        z[j++] = zArg[i];
        if( zArg[i]=='\'' ){
          z[j++] = '\'';
        }
      }
      z[j++] = '\'';
      z[j] = 0;
      sqlite3_result_text(context, z, j, SQLITE_TRANSIENT);
      sqlite3_free(z);
    }
  }
}

/*
** The hex() function.  Interpret the argument as a blob.  Return
** a hexadecimal rendering as text.
................................................................................
** WARNING: Not threadsafe.
*/
static int test_destructor_count_var = 0;
static void destructor(void *p){
  char *zVal = (char *)p;
  assert(zVal);
  zVal--;
  sqlite3_free(zVal);
  test_destructor_count_var--;
}
static void test_destructor(
  sqlite3_context *pCtx, 
  int nArg,
  sqlite3_value **argv
){
................................................................................
** The test_auxdata() SQL function attempts to register each of its arguments
** as auxiliary data.  If there are no prior registrations of aux data for
** that argument (meaning the argument is not a constant or this is its first
** call) then the result for that argument is 0.  If there is a prior
** registration, the result for that argument is 1.  The overall result
** is the individual argument results separated by spaces.
*/
static void free_test_auxdata(void *p) {sqlite3_free(p);}
static void test_auxdata(
  sqlite3_context *pCtx, 
  int nArg,
  sqlite3_value **argv
){
  int i;
  char *zRet = sqliteMalloc(nArg*2);
................................................................................
        if( strcmp(zAux, z) ){
          free_test_auxdata((void *)zRet);
          sqlite3_result_error(pCtx, "Auxilary data corruption", -1);
          return;
        }
      }else{
        zRet[i*2] = '0';
        zAux = sqlite3StrDup(z);
        sqlite3_set_auxdata(pCtx, i, zAux, free_test_auxdata);
      }
      zRet[i*2+1] = ' ';
    }
  }
  sqlite3_result_text(pCtx, zRet, 2*nArg-1, free_test_auxdata);
}

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This is the implementation of generic hash-tables
** used in SQLite.
**
** $Id: hash.c,v 1.19 2007/03/31 03:59:24 drh Exp $
*/
#include "sqliteInt.h"
#include <assert.h>

/* Turn bulk memory into a hash table object by initializing the
** fields of the Hash structure.
**
................................................................................
  if( keyClass==SQLITE_HASH_POINTER || keyClass==SQLITE_HASH_INT ) copyKey = 0;
#endif
  pNew->copyKey = copyKey;
  pNew->first = 0;
  pNew->count = 0;
  pNew->htsize = 0;
  pNew->ht = 0;
  pNew->xMalloc = sqlite3MallocX;
  pNew->xFree = sqlite3FreeX;
}

/* Remove all entries from a hash table.  Reclaim all memory.
** Call this routine to delete a hash table or to reset a hash table
** to the empty state.
*/
void sqlite3HashClear(Hash *pH){
  HashElem *elem;         /* For looping over all elements of the table */

  assert( pH!=0 );
  elem = pH->first;
  pH->first = 0;
  if( pH->ht ) pH->xFree(pH->ht);
  pH->ht = 0;
  pH->htsize = 0;
  while( elem ){
    HashElem *next_elem = elem->next;
    if( pH->copyKey && elem->pKey ){
      pH->xFree(elem->pKey);
    }
    pH->xFree(elem);
    elem = next_elem;
  }
  pH->count = 0;
}

#if 0 /* NOT USED */
/*
................................................................................
  pEntry->count++;
  pEntry->chain = pNew;
}


/* Resize the hash table so that it cantains "new_size" buckets.
** "new_size" must be a power of 2.  The hash table might fail 
** to resize if sqliteMalloc() fails.
*/
static void rehash(Hash *pH, int new_size){
  struct _ht *new_ht;            /* The new hash table */
  HashElem *elem, *next_elem;    /* For looping over existing elements */
  int (*xHash)(const void*,int); /* The hash function */

  assert( (new_size & (new_size-1))==0 );
  new_ht = (struct _ht *)pH->xMalloc( new_size*sizeof(struct _ht) );
  if( new_ht==0 ) return;
  if( pH->ht ) pH->xFree(pH->ht);
  pH->ht = new_ht;
  pH->htsize = new_size;
  xHash = hashFunction(pH->keyClass);
  for(elem=pH->first, pH->first=0; elem; elem = next_elem){
    int h = (*xHash)(elem->pKey, elem->nKey) & (new_size-1);
    next_elem = elem->next;
    insertElement(pH, &new_ht[h], elem);
................................................................................
    pEntry->chain = elem->next;
  }
  pEntry->count--;
  if( pEntry->count<=0 ){
    pEntry->chain = 0;
  }
  if( pH->copyKey ){
    pH->xFree(elem->pKey);
  }
  pH->xFree( elem );
  pH->count--;
  if( pH->count<=0 ){
    assert( pH->first==0 );
    assert( pH->count==0 );
    sqlite3HashClear(pH);
  }
}
................................................................................
      removeElementGivenHash(pH,elem,h);
    }else{
      elem->data = data;
    }
    return old_data;
  }
  if( data==0 ) return 0;
  new_elem = (HashElem*)pH->xMalloc( sizeof(HashElem) );
  if( new_elem==0 ) return data;
  if( pH->copyKey && pKey!=0 ){
    new_elem->pKey = pH->xMalloc( nKey );
    if( new_elem->pKey==0 ){
      pH->xFree(new_elem);
      return data;
    }
    memcpy((void*)new_elem->pKey, pKey, nKey);
  }else{
    new_elem->pKey = (void*)pKey;
  }
  new_elem->nKey = nKey;
  pH->count++;
  if( pH->htsize==0 ){
    rehash(pH,8);
    if( pH->htsize==0 ){
      pH->count = 0;
      if( pH->copyKey ){
        pH->xFree(new_elem->pKey);
      }
      pH->xFree(new_elem);
      return data;
    }
  }
  if( pH->count > pH->htsize ){
    rehash(pH,pH->htsize*2);
  }
  assert( pH->htsize>0 );
  assert( (pH->htsize & (pH->htsize-1))==0 );
  h = hraw & (pH->htsize-1);
  insertElement(pH, &pH->ht[h], new_elem);
  new_elem->data = data;
  return 0;
}

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This is the implementation of generic hash-tables
** used in SQLite.
**
** $Id: hash.c,v 1.20 2007/08/16 04:30:40 drh Exp $
*/
#include "sqliteInt.h"
#include <assert.h>

/* Turn bulk memory into a hash table object by initializing the
** fields of the Hash structure.
**
................................................................................
  if( keyClass==SQLITE_HASH_POINTER || keyClass==SQLITE_HASH_INT ) copyKey = 0;
#endif
  pNew->copyKey = copyKey;
  pNew->first = 0;
  pNew->count = 0;
  pNew->htsize = 0;
  pNew->ht = 0;


}

/* Remove all entries from a hash table.  Reclaim all memory.
** Call this routine to delete a hash table or to reset a hash table
** to the empty state.
*/
void sqlite3HashClear(Hash *pH){
  HashElem *elem;         /* For looping over all elements of the table */

  assert( pH!=0 );
  elem = pH->first;
  pH->first = 0;
  if( pH->ht ) sqlite3_free(pH->ht);
  pH->ht = 0;
  pH->htsize = 0;
  while( elem ){
    HashElem *next_elem = elem->next;
    if( pH->copyKey && elem->pKey ){
      sqlite3_free(elem->pKey);
    }
    sqlite3_free(elem);
    elem = next_elem;
  }
  pH->count = 0;
}

#if 0 /* NOT USED */
/*
................................................................................
  pEntry->count++;
  pEntry->chain = pNew;
}


/* Resize the hash table so that it cantains "new_size" buckets.
** "new_size" must be a power of 2.  The hash table might fail 
** to resize if sqlite3_malloc() fails.
*/
static void rehash(Hash *pH, int new_size){
  struct _ht *new_ht;            /* The new hash table */
  HashElem *elem, *next_elem;    /* For looping over existing elements */
  int (*xHash)(const void*,int); /* The hash function */

  assert( (new_size & (new_size-1))==0 );
  new_ht = (struct _ht *)sqlite3_malloc( new_size*sizeof(struct _ht) );
  if( new_ht==0 ) return;
  if( pH->ht ) sqlite3_free(pH->ht);
  pH->ht = new_ht;
  pH->htsize = new_size;
  xHash = hashFunction(pH->keyClass);
  for(elem=pH->first, pH->first=0; elem; elem = next_elem){
    int h = (*xHash)(elem->pKey, elem->nKey) & (new_size-1);
    next_elem = elem->next;
    insertElement(pH, &new_ht[h], elem);
................................................................................
    pEntry->chain = elem->next;
  }
  pEntry->count--;
  if( pEntry->count<=0 ){
    pEntry->chain = 0;
  }
  if( pH->copyKey ){
    sqlite3_free(elem->pKey);
  }
  sqlite3_free( elem );
  pH->count--;
  if( pH->count<=0 ){
    assert( pH->first==0 );
    assert( pH->count==0 );
    sqlite3HashClear(pH);
  }
}
................................................................................
      removeElementGivenHash(pH,elem,h);
    }else{
      elem->data = data;
    }
    return old_data;
  }
  if( data==0 ) return 0;
  new_elem = (HashElem*)sqlite3_malloc( sizeof(HashElem) );
  if( new_elem==0 ) return data;
  if( pH->copyKey && pKey!=0 ){
    new_elem->pKey = sqlite3_malloc( nKey );
    if( new_elem->pKey==0 ){
      sqlite3_free(new_elem);
      return data;
    }
    memcpy((void*)new_elem->pKey, pKey, nKey);
  }else{
    new_elem->pKey = (void*)pKey;
  }
  new_elem->nKey = nKey;
  pH->count++;
  if( pH->htsize==0 ){
    rehash(pH,8);
    if( pH->htsize==0 ){
      pH->count = 0;
      if( pH->copyKey ){
        sqlite3_free(new_elem->pKey);
      }
      sqlite3_free(new_elem);
      return data;
    }
  }
  if( pH->count > pH->htsize ){
    rehash(pH,pH->htsize*2);
  }
  assert( pH->htsize>0 );
  assert( (pH->htsize & (pH->htsize-1))==0 );
  h = hraw & (pH->htsize-1);
  insertElement(pH, &pH->ht[h], new_elem);
  new_elem->data = data;
  return 0;
}

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This is the header file for the generic hash-table implemenation
** used in SQLite.
**
** $Id: hash.h,v 1.9 2006/02/14 10:48:39 danielk1977 Exp $
*/
#ifndef _SQLITE_HASH_H_
#define _SQLITE_HASH_H_

/* Forward declarations of structures. */
typedef struct Hash Hash;
typedef struct HashElem HashElem;
................................................................................
** accessing this structure are really macros, so we can't really make
** this structure opaque.
*/
struct Hash {
  char keyClass;          /* SQLITE_HASH_INT, _POINTER, _STRING, _BINARY */
  char copyKey;           /* True if copy of key made on insert */
  int count;              /* Number of entries in this table */
  HashElem *first;        /* The first element of the array */
  void *(*xMalloc)(int);  /* malloc() function to use */
  void (*xFree)(void *);  /* free() function to use */
  int htsize;             /* Number of buckets in the hash table */

  struct _ht {            /* the hash table */
    int count;               /* Number of entries with this hash */
    HashElem *chain;         /* Pointer to first entry with this hash */
  } *ht;
};

/* Each element in the hash table is an instance of the following 

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This is the header file for the generic hash-table implemenation
** used in SQLite.
**
** $Id: hash.h,v 1.10 2007/08/16 04:30:40 drh Exp $
*/
#ifndef _SQLITE_HASH_H_
#define _SQLITE_HASH_H_

/* Forward declarations of structures. */
typedef struct Hash Hash;
typedef struct HashElem HashElem;
................................................................................
** accessing this structure are really macros, so we can't really make
** this structure opaque.
*/
struct Hash {
  char keyClass;          /* SQLITE_HASH_INT, _POINTER, _STRING, _BINARY */
  char copyKey;           /* True if copy of key made on insert */
  int count;              /* Number of entries in this table */



  int htsize;             /* Number of buckets in the hash table */
  HashElem *first;        /* The first element of the array */
  struct _ht {            /* the hash table */
    int count;               /* Number of entries with this hash */
    HashElem *chain;         /* Pointer to first entry with this hash */
  } *ht;
};

/* Each element in the hash table is an instance of the following 

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains C code routines that are called by the parser
** to handle INSERT statements in SQLite.
**
** $Id: insert.c,v 1.188 2007/07/23 19:39:47 drh Exp $
*/
#include "sqliteInt.h"

/*
** Set P3 of the most recently inserted opcode to a column affinity
** string for index pIdx. A column affinity string has one character
** for each column in the table, according to the affinity of the column:
................................................................................
    **
    ** The column affinity string will eventually be deleted by
    ** sqliteDeleteIndex() when the Index structure itself is cleaned
    ** up.
    */
    int n;
    Table *pTab = pIdx->pTable;

    pIdx->zColAff = (char *)sqliteMalloc(pIdx->nColumn+1);
    if( !pIdx->zColAff ){
      return;
    }
    for(n=0; n<pIdx->nColumn; n++){
      pIdx->zColAff[n] = pTab->aCol[pIdx->aiColumn[n]].affinity;
    }
    pIdx->zColAff[pIdx->nColumn] = '\0';
................................................................................
  **
  ** The column affinity string will eventually be deleted by
  ** sqlite3DeleteTable() when the Table structure itself is cleaned up.
  */
  if( !pTab->zColAff ){
    char *zColAff;
    int i;


    zColAff = (char *)sqliteMalloc(pTab->nCol+1);
    if( !zColAff ){
      return;
    }

    for(i=0; i<pTab->nCol; i++){
      zColAff[i] = pTab->aCol[i].affinity;
    }
................................................................................
  int nHidden = 0;

#ifndef SQLITE_OMIT_TRIGGER
  int isView;                 /* True if attempting to insert into a view */
  int triggers_exist = 0;     /* True if there are FOR EACH ROW triggers */
#endif


  if( pParse->nErr || sqlite3MallocFailed() ){
    goto insert_cleanup;
  }
  db = pParse->db;

  /* Locate the table into which we will be inserting new information.
  */
  assert( pTabList->nSrc==1 );
  zTab = pTabList->a[0].zName;
  if( zTab==0 ) goto insert_cleanup;
  pTab = sqlite3SrcListLookup(pParse, pTabList);
................................................................................
    int rc, iInitCode;
    iInitCode = sqlite3VdbeAddOp(v, OP_Goto, 0, 0);
    iSelectLoop = sqlite3VdbeCurrentAddr(v);
    iInsertBlock = sqlite3VdbeMakeLabel(v);

    /* Resolve the expressions in the SELECT statement and execute it. */
    rc = sqlite3Select(pParse, pSelect, SRT_Subroutine, iInsertBlock,0,0,0,0);
    if( rc || pParse->nErr || sqlite3MallocFailed() ){
      goto insert_cleanup;
    }

    iCleanup = sqlite3VdbeMakeLabel(v);
    sqlite3VdbeAddOp(v, OP_Goto, 0, iCleanup);
    assert( pSelect->pEList );
    nColumn = pSelect->pEList->nExpr;

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains C code routines that are called by the parser
** to handle INSERT statements in SQLite.
**
** $Id: insert.c,v 1.189 2007/08/16 04:30:40 drh Exp $
*/
#include "sqliteInt.h"

/*
** Set P3 of the most recently inserted opcode to a column affinity
** string for index pIdx. A column affinity string has one character
** for each column in the table, according to the affinity of the column:
................................................................................
    **
    ** The column affinity string will eventually be deleted by
    ** sqliteDeleteIndex() when the Index structure itself is cleaned
    ** up.
    */
    int n;
    Table *pTab = pIdx->pTable;
    sqlite3 *db = sqlite3DbOfVdbe(v);
    pIdx->zColAff = (char *)sqlite3DbMallocZero(db, pIdx->nColumn+1);
    if( !pIdx->zColAff ){
      return;
    }
    for(n=0; n<pIdx->nColumn; n++){
      pIdx->zColAff[n] = pTab->aCol[pIdx->aiColumn[n]].affinity;
    }
    pIdx->zColAff[pIdx->nColumn] = '\0';
................................................................................
  **
  ** The column affinity string will eventually be deleted by
  ** sqlite3DeleteTable() when the Table structure itself is cleaned up.
  */
  if( !pTab->zColAff ){
    char *zColAff;
    int i;
    sqlite3 *db = sqlite3DbOfVdbe(v);

    zColAff = (char *)sqlite3DbMallocZero(db, pTab->nCol+1);
    if( !zColAff ){
      return;
    }

    for(i=0; i<pTab->nCol; i++){
      zColAff[i] = pTab->aCol[i].affinity;
    }
................................................................................
  int nHidden = 0;

#ifndef SQLITE_OMIT_TRIGGER
  int isView;                 /* True if attempting to insert into a view */
  int triggers_exist = 0;     /* True if there are FOR EACH ROW triggers */
#endif

  db = pParse->db;
  if( pParse->nErr || db->mallocFailed ){
    goto insert_cleanup;
  }


  /* Locate the table into which we will be inserting new information.
  */
  assert( pTabList->nSrc==1 );
  zTab = pTabList->a[0].zName;
  if( zTab==0 ) goto insert_cleanup;
  pTab = sqlite3SrcListLookup(pParse, pTabList);
................................................................................
    int rc, iInitCode;
    iInitCode = sqlite3VdbeAddOp(v, OP_Goto, 0, 0);
    iSelectLoop = sqlite3VdbeCurrentAddr(v);
    iInsertBlock = sqlite3VdbeMakeLabel(v);

    /* Resolve the expressions in the SELECT statement and execute it. */
    rc = sqlite3Select(pParse, pSelect, SRT_Subroutine, iInsertBlock,0,0,0,0);
    if( rc || pParse->nErr || db->mallocFailed ){
      goto insert_cleanup;
    }

    iCleanup = sqlite3VdbeMakeLabel(v);
    sqlite3VdbeAddOp(v, OP_Goto, 0, iCleanup);
    assert( pSelect->pEList );
    nColumn = pSelect->pEList->nExpr;

**
*************************************************************************
** Main file for the SQLite library.  The routines in this file
** implement the programmer interface to the library.  Routines in
** other files are for internal use by SQLite and should not be
** accessed by users of the library.
**
** $Id: legacy.c,v 1.18 2007/05/04 13:15:56 drh Exp $
*/

#include "sqliteInt.h"
#include "os.h"
#include <ctype.h>

/*
................................................................................
      zSql = zLeftover;
      continue;
    }

    nCallback = 0;

    nCol = sqlite3_column_count(pStmt);
    azCols = sqliteMalloc(2*nCol*sizeof(const char *) + 1);
    if( azCols==0 ){
      goto exec_out;
    }

    while( 1 ){
      int i;
      rc = sqlite3_step(pStmt);
................................................................................
          zSql = zLeftover;
          while( isspace((unsigned char)zSql[0]) ) zSql++;
        }
        break;
      }
    }

    sqliteFree(azCols);
    azCols = 0;
  }

exec_out:
  if( pStmt ) sqlite3_finalize(pStmt);
  if( azCols ) sqliteFree(azCols);

  rc = sqlite3ApiExit(0, rc);
  if( rc!=SQLITE_OK && rc==sqlite3_errcode(db) && pzErrMsg ){
    int nErrMsg = 1 + strlen(sqlite3_errmsg(db));
    *pzErrMsg = sqlite3_malloc(nErrMsg);
    if( *pzErrMsg ){
      memcpy(*pzErrMsg, sqlite3_errmsg(db), nErrMsg);

**
*************************************************************************
** Main file for the SQLite library.  The routines in this file
** implement the programmer interface to the library.  Routines in
** other files are for internal use by SQLite and should not be
** accessed by users of the library.
**
** $Id: legacy.c,v 1.19 2007/08/16 04:30:40 drh Exp $
*/

#include "sqliteInt.h"
#include "os.h"
#include <ctype.h>

/*
................................................................................
      zSql = zLeftover;
      continue;
    }

    nCallback = 0;

    nCol = sqlite3_column_count(pStmt);
    azCols = sqlite3DbMallocZero(db, 2*nCol*sizeof(const char *) + 1);
    if( azCols==0 ){
      goto exec_out;
    }

    while( 1 ){
      int i;
      rc = sqlite3_step(pStmt);
................................................................................
          zSql = zLeftover;
          while( isspace((unsigned char)zSql[0]) ) zSql++;
        }
        break;
      }
    }

    sqlite3_free(azCols);
    azCols = 0;
  }

exec_out:
  if( pStmt ) sqlite3_finalize(pStmt);
  if( azCols ) sqlite3_free(azCols);

  rc = sqlite3ApiExit(0, rc);
  if( rc!=SQLITE_OK && rc==sqlite3_errcode(db) && pzErrMsg ){
    int nErrMsg = 1 + strlen(sqlite3_errmsg(db));
    *pzErrMsg = sqlite3_malloc(nErrMsg);
    if( *pzErrMsg ){
      memcpy(*pzErrMsg, sqlite3_errmsg(db), nErrMsg);

    sqlite3_free(zErrmsg);
    sqlite3OsDlclose(handle);
    return SQLITE_ERROR;
  }

  /* Append the new shared library handle to the db->aExtension array. */
  db->nExtension++;
  aHandle = sqliteMalloc(sizeof(handle)*db->nExtension);
  if( aHandle==0 ){
    return SQLITE_NOMEM;
  }
  if( db->nExtension>0 ){
    memcpy(aHandle, db->aExtension, sizeof(handle)*(db->nExtension-1));
  }
  sqliteFree(db->aExtension);
  db->aExtension = aHandle;

  db->aExtension[db->nExtension-1] = handle;
  return SQLITE_OK;
}

/*
................................................................................
** to clean up loaded extensions
*/
void sqlite3CloseExtensions(sqlite3 *db){
  int i;
  for(i=0; i<db->nExtension; i++){
    sqlite3OsDlclose(db->aExtension[i]);
  }
  sqliteFree(db->aExtension);
}

/*
** Enable or disable extension loading.  Extension loading is disabled by
** default so as not to open security holes in older applications.
*/
int sqlite3_enable_load_extension(sqlite3 *db, int onoff){
................................................................................
  int rc = SQLITE_OK;
  sqlite3OsEnterMutex();
  for(i=0; i<nAutoExtension; i++){
    if( aAutoExtension[i]==xInit ) break;
  }
  if( i==nAutoExtension ){
    nAutoExtension++;
    aAutoExtension = sqlite3Realloc( aAutoExtension,
                                     nAutoExtension*sizeof(aAutoExtension[0]) );
    if( aAutoExtension==0 ){
      nAutoExtension = 0;
      rc = SQLITE_NOMEM;
    }else{
      aAutoExtension[nAutoExtension-1] = xInit;
    }
................................................................................
}

/*
** Reset the automatic extension loading mechanism.
*/
void sqlite3_reset_auto_extension(void){
  sqlite3OsEnterMutex();
  sqliteFree(aAutoExtension);
  aAutoExtension = 0;
  nAutoExtension = 0;
  sqlite3OsLeaveMutex();
}

/*
** Load all automatic extensions.

    sqlite3_free(zErrmsg);
    sqlite3OsDlclose(handle);
    return SQLITE_ERROR;
  }

  /* Append the new shared library handle to the db->aExtension array. */
  db->nExtension++;
  aHandle = sqlite3DbMallocZero(db, sizeof(handle)*db->nExtension);
  if( aHandle==0 ){
    return SQLITE_NOMEM;
  }
  if( db->nExtension>0 ){
    memcpy(aHandle, db->aExtension, sizeof(handle)*(db->nExtension-1));
  }
  sqlite3_free(db->aExtension);
  db->aExtension = aHandle;

  db->aExtension[db->nExtension-1] = handle;
  return SQLITE_OK;
}

/*
................................................................................
** to clean up loaded extensions
*/
void sqlite3CloseExtensions(sqlite3 *db){
  int i;
  for(i=0; i<db->nExtension; i++){
    sqlite3OsDlclose(db->aExtension[i]);
  }
  sqlite3_free(db->aExtension);
}

/*
** Enable or disable extension loading.  Extension loading is disabled by
** default so as not to open security holes in older applications.
*/
int sqlite3_enable_load_extension(sqlite3 *db, int onoff){
................................................................................
  int rc = SQLITE_OK;
  sqlite3OsEnterMutex();
  for(i=0; i<nAutoExtension; i++){
    if( aAutoExtension[i]==xInit ) break;
  }
  if( i==nAutoExtension ){
    nAutoExtension++;
    aAutoExtension = sqlite3_realloc( aAutoExtension,
                                     nAutoExtension*sizeof(aAutoExtension[0]) );
    if( aAutoExtension==0 ){
      nAutoExtension = 0;
      rc = SQLITE_NOMEM;
    }else{
      aAutoExtension[nAutoExtension-1] = xInit;
    }
................................................................................
}

/*
** Reset the automatic extension loading mechanism.
*/
void sqlite3_reset_auto_extension(void){
  sqlite3OsEnterMutex();
  sqlite3_free(aAutoExtension);
  aAutoExtension = 0;
  nAutoExtension = 0;
  sqlite3OsLeaveMutex();
}

/*
** Load all automatic extensions.

**
*************************************************************************
** Main file for the SQLite library.  The routines in this file
** implement the programmer interface to the library.  Routines in
** other files are for internal use by SQLite and should not be
** accessed by users of the library.
**
** $Id: main.c,v 1.379 2007/08/15 13:04:54 drh Exp $
*/
#include "sqliteInt.h"
#include "os.h"
#include <ctype.h>

/*
** The version of the library
................................................................................
  sqlite3ResetInternalSchema(db, 0);
  assert( db->nDb<=2 );
  assert( db->aDb==db->aDbStatic );
  for(i=sqliteHashFirst(&db->aFunc); i; i=sqliteHashNext(i)){
    FuncDef *pFunc, *pNext;
    for(pFunc = (FuncDef*)sqliteHashData(i); pFunc; pFunc=pNext){
      pNext = pFunc->pNext;
      sqliteFree(pFunc);
    }
  }

  for(i=sqliteHashFirst(&db->aCollSeq); i; i=sqliteHashNext(i)){
    CollSeq *pColl = (CollSeq *)sqliteHashData(i);
    /* Invoke any destructors registered for collation sequence user data. */
    for(j=0; j<3; j++){
      if( pColl[j].xDel ){
        pColl[j].xDel(pColl[j].pUser);
      }
    }
    sqliteFree(pColl);
  }
  sqlite3HashClear(&db->aCollSeq);
#ifndef SQLITE_OMIT_VIRTUALTABLE
  for(i=sqliteHashFirst(&db->aModule); i; i=sqliteHashNext(i)){
    Module *pMod = (Module *)sqliteHashData(i);
    if( pMod->xDestroy ){
      pMod->xDestroy(pMod->pAux);
    }
    sqliteFree(pMod);
  }
  sqlite3HashClear(&db->aModule);
#endif

  sqlite3HashClear(&db->aFunc);
  sqlite3Error(db, SQLITE_OK, 0); /* Deallocates any cached error strings. */
  if( db->pErr ){
................................................................................

  /* The temp-database schema is allocated differently from the other schema
  ** objects (using sqliteMalloc() directly, instead of sqlite3BtreeSchema()).
  ** So it needs to be freed here. Todo: Why not roll the temp schema into
  ** the same sqliteMalloc() as the one that allocates the database 
  ** structure?
  */
  sqliteFree(db->aDb[1].pSchema);
  sqliteFree(db);
  sqlite3ReleaseThreadData();
  return SQLITE_OK;
}

/*
** Rollback all database files.
*/
................................................................................
  ** operation to continue but invalidate all precompiled statements.
  */
  p = sqlite3FindFunction(db, zFunctionName, nName, nArg, enc, 0);
  if( p && p->iPrefEnc==enc && p->nArg==nArg ){
    if( db->activeVdbeCnt ){
      sqlite3Error(db, SQLITE_BUSY, 
        "Unable to delete/modify user-function due to active statements");
      assert( !sqlite3MallocFailed() );
      return SQLITE_BUSY;
    }else{
      sqlite3ExpirePreparedStatements(db);
    }
  }

  p = sqlite3FindFunction(db, zFunctionName, nName, nArg, enc, 1);
................................................................................
  int enc,
  void *p,
  void (*xFunc)(sqlite3_context*,int,sqlite3_value **),
  void (*xStep)(sqlite3_context*,int,sqlite3_value **),
  void (*xFinal)(sqlite3_context*)
){
  int rc;
  assert( !sqlite3MallocFailed() );
  rc = sqlite3CreateFunc(db, zFunctionName, nArg, enc, p, xFunc, xStep, xFinal);

  return sqlite3ApiExit(db, rc);
}

#ifndef SQLITE_OMIT_UTF16
int sqlite3_create_function16(
................................................................................
  void *p,
  void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
  void (*xStep)(sqlite3_context*,int,sqlite3_value**),
  void (*xFinal)(sqlite3_context*)
){
  int rc;
  char *zFunc8;
  assert( !sqlite3MallocFailed() );

  zFunc8 = sqlite3Utf16to8(zFunctionName, -1);
  rc = sqlite3CreateFunc(db, zFunc8, nArg, eTextRep, p, xFunc, xStep, xFinal);
  sqliteFree(zFunc8);

  return sqlite3ApiExit(db, rc);
}
#endif


/*
................................................................................

/*
** Return UTF-8 encoded English language explanation of the most recent
** error.
*/
const char *sqlite3_errmsg(sqlite3 *db){
  const char *z;
  assert( !sqlite3MallocFailed() );
  if( !db ){
    return sqlite3ErrStr(SQLITE_NOMEM);
  }

  if( sqlite3SafetyCheck(db) || db->errCode==SQLITE_MISUSE ){
    return sqlite3ErrStr(SQLITE_MISUSE);
  }
  z = (char*)sqlite3_value_text(db->pErr);
  if( z==0 ){
    z = sqlite3ErrStr(db->errCode);
  }
................................................................................
    0, 'c', 0, 'a', 0, 'l', 0, 'l', 0, 'e', 0, 'd', 0, ' ', 
    0, 'o', 0, 'u', 0, 't', 0, ' ', 
    0, 'o', 0, 'f', 0, ' ', 
    0, 's', 0, 'e', 0, 'q', 0, 'u', 0, 'e', 0, 'n', 0, 'c', 0, 'e', 0, 0, 0
  };

  const void *z;
  assert( !sqlite3MallocFailed() );
  if( !db ){
    return (void *)(&outOfMemBe[SQLITE_UTF16NATIVE==SQLITE_UTF16LE?1:0]);
  }
  if( sqlite3SafetyCheck(db) || db->errCode==SQLITE_MISUSE ){
    return (void *)(&misuseBe[SQLITE_UTF16NATIVE==SQLITE_UTF16LE?1:0]);
  }
  z = sqlite3_value_text16(db->pErr);
................................................................................
#endif /* SQLITE_OMIT_UTF16 */

/*
** Return the most recent error code generated by an SQLite routine. If NULL is
** passed to this function, we assume a malloc() failed during sqlite3_open().
*/
int sqlite3_errcode(sqlite3 *db){
  if( !db || sqlite3MallocFailed() ){
    return SQLITE_NOMEM;
  }
  if( sqlite3SafetyCheck(db) ){
    return SQLITE_MISUSE;
  }
  return db->errCode & db->errMask;
}
................................................................................
  const char *zFilename, /* Database filename UTF-8 encoded */
  sqlite3 **ppDb         /* OUT: Returned database handle */
){
  sqlite3 *db;
  int rc;
  CollSeq *pColl;

  assert( !sqlite3MallocFailed() );

  /* Allocate the sqlite data structure */
  db = sqliteMalloc( sizeof(sqlite3) );
  if( db==0 ) goto opendb_out;
  db->errMask = 0xff;
  db->priorNewRowid = 0;
  db->magic = SQLITE_MAGIC_BUSY;
  db->nDb = 2;
  db->aDb = db->aDbStatic;
  db->autoCommit = 1;
................................................................................
  ** conversions. The only error that can occur here is a malloc() failure.
  */
  if( createCollation(db, "BINARY", SQLITE_UTF8, 0, binCollFunc, 0) ||
      createCollation(db, "BINARY", SQLITE_UTF16BE, 0, binCollFunc, 0) ||
      createCollation(db, "BINARY", SQLITE_UTF16LE, 0, binCollFunc, 0) ||
      (db->pDfltColl = sqlite3FindCollSeq(db, SQLITE_UTF8, "BINARY", 6, 0))==0 
  ){
    assert( sqlite3MallocFailed() );
    db->magic = SQLITE_MAGIC_CLOSED;
    goto opendb_out;
  }

  /* Also add a UTF-8 case-insensitive collation sequence. */
  createCollation(db, "NOCASE", SQLITE_UTF8, 0, nocaseCollatingFunc, 0);

................................................................................
  rc = sqlite3BtreeFactory(db, zFilename, 0, SQLITE_DEFAULT_CACHE_SIZE,
                           &db->aDb[0].pBt);
  if( rc!=SQLITE_OK ){
    sqlite3Error(db, rc, 0);
    db->magic = SQLITE_MAGIC_CLOSED;
    goto opendb_out;
  }
  db->aDb[0].pSchema = sqlite3SchemaGet(db->aDb[0].pBt);
  db->aDb[1].pSchema = sqlite3SchemaGet(0);


  /* The default safety_level for the main database is 'full'; for the temp
  ** database it is 'NONE'. This matches the pager layer defaults.  
  */
  db->aDb[0].zName = "main";
  db->aDb[0].safety_level = 3;
#ifndef SQLITE_OMIT_TEMPDB
  db->aDb[1].zName = "temp";
  db->aDb[1].safety_level = 1;
#endif

  db->magic = SQLITE_MAGIC_OPEN;
  if( sqlite3MallocFailed() ){
    goto opendb_out;
  }

  /* Register all built-in functions, but do not attempt to read the
  ** database schema yet. This is delayed until the first time the database
  ** is accessed.
  */
................................................................................
  */
  (void)sqlite3AutoLoadExtensions(db);
  if( sqlite3_errcode(db)!=SQLITE_OK ){
    goto opendb_out;
  }

#ifdef SQLITE_ENABLE_FTS1
  if( !sqlite3MallocFailed() ){
    extern int sqlite3Fts1Init(sqlite3*);
    rc = sqlite3Fts1Init(db);
  }
#endif

#ifdef SQLITE_ENABLE_FTS2
  if( !sqlite3MallocFailed() && rc==SQLITE_OK ){
    extern int sqlite3Fts2Init(sqlite3*);
    rc = sqlite3Fts2Init(db);
  }
#endif

#ifdef SQLITE_ENABLE_ICU
  if( !sqlite3MallocFailed() && rc==SQLITE_OK ){
    extern int sqlite3IcuInit(sqlite3*);
    rc = sqlite3IcuInit(db);
  }
#endif
  sqlite3Error(db, rc, 0);

  /* -DSQLITE_DEFAULT_LOCKING_MODE=1 makes EXCLUSIVE the default locking
................................................................................
  sqlite3* db, 
  const char *zName, 
  int enc, 
  void* pCtx,
  int(*xCompare)(void*,int,const void*,int,const void*)
){
  int rc;
  assert( !sqlite3MallocFailed() );
  rc = createCollation(db, zName, enc, pCtx, xCompare, 0);
  return sqlite3ApiExit(db, rc);
}

/*
** Register a new collation sequence with the database handle db.
*/
................................................................................
  const char *zName, 
  int enc, 
  void* pCtx,
  int(*xCompare)(void*,int,const void*,int,const void*),
  void(*xDel)(void*)
){
  int rc;
  assert( !sqlite3MallocFailed() );
  rc = createCollation(db, zName, enc, pCtx, xCompare, xDel);
  return sqlite3ApiExit(db, rc);
}

#ifndef SQLITE_OMIT_UTF16
/*
** Register a new collation sequence with the database handle db.
................................................................................
  const char *zName, 
  int enc, 
  void* pCtx,
  int(*xCompare)(void*,int,const void*,int,const void*)
){
  int rc = SQLITE_OK;
  char *zName8; 
  assert( !sqlite3MallocFailed() );
  zName8 = sqlite3Utf16to8(zName, -1);
  if( zName8 ){
    rc = createCollation(db, zName8, enc, pCtx, xCompare, 0);
    sqliteFree(zName8);
  }
  return sqlite3ApiExit(db, rc);
}
#endif /* SQLITE_OMIT_UTF16 */

/*
** Register a collation sequence factory callback with the database handle
................................................................................

  if( SQLITE_OK==rc && !pTab ){
    sqlite3SetString(&zErrMsg, "no such table column: ", zTableName, ".", 
        zColumnName, 0);
    rc = SQLITE_ERROR;
  }
  sqlite3Error(db, rc, (zErrMsg?"%s":0), zErrMsg);
  sqliteFree(zErrMsg);
  return sqlite3ApiExit(db, rc);
}
#endif

/*
** Set all the parameters in the compiled SQL statement to NULL.
*/

**
*************************************************************************
** Main file for the SQLite library.  The routines in this file
** implement the programmer interface to the library.  Routines in
** other files are for internal use by SQLite and should not be
** accessed by users of the library.
**
** $Id: main.c,v 1.380 2007/08/16 04:30:40 drh Exp $
*/
#include "sqliteInt.h"
#include "os.h"
#include <ctype.h>

/*
** The version of the library
................................................................................
  sqlite3ResetInternalSchema(db, 0);
  assert( db->nDb<=2 );
  assert( db->aDb==db->aDbStatic );
  for(i=sqliteHashFirst(&db->aFunc); i; i=sqliteHashNext(i)){
    FuncDef *pFunc, *pNext;
    for(pFunc = (FuncDef*)sqliteHashData(i); pFunc; pFunc=pNext){
      pNext = pFunc->pNext;
      sqlite3_free(pFunc);
    }
  }

  for(i=sqliteHashFirst(&db->aCollSeq); i; i=sqliteHashNext(i)){
    CollSeq *pColl = (CollSeq *)sqliteHashData(i);
    /* Invoke any destructors registered for collation sequence user data. */
    for(j=0; j<3; j++){
      if( pColl[j].xDel ){
        pColl[j].xDel(pColl[j].pUser);
      }
    }
    sqlite3_free(pColl);
  }
  sqlite3HashClear(&db->aCollSeq);
#ifndef SQLITE_OMIT_VIRTUALTABLE
  for(i=sqliteHashFirst(&db->aModule); i; i=sqliteHashNext(i)){
    Module *pMod = (Module *)sqliteHashData(i);
    if( pMod->xDestroy ){
      pMod->xDestroy(pMod->pAux);
    }
    sqlite3_free(pMod);
  }
  sqlite3HashClear(&db->aModule);
#endif

  sqlite3HashClear(&db->aFunc);
  sqlite3Error(db, SQLITE_OK, 0); /* Deallocates any cached error strings. */
  if( db->pErr ){
................................................................................

  /* The temp-database schema is allocated differently from the other schema
  ** objects (using sqliteMalloc() directly, instead of sqlite3BtreeSchema()).
  ** So it needs to be freed here. Todo: Why not roll the temp schema into
  ** the same sqliteMalloc() as the one that allocates the database 
  ** structure?
  */
  sqlite3_free(db->aDb[1].pSchema);
  sqlite3_free(db);
  sqlite3ReleaseThreadData();
  return SQLITE_OK;
}

/*
** Rollback all database files.
*/
................................................................................
  ** operation to continue but invalidate all precompiled statements.
  */
  p = sqlite3FindFunction(db, zFunctionName, nName, nArg, enc, 0);
  if( p && p->iPrefEnc==enc && p->nArg==nArg ){
    if( db->activeVdbeCnt ){
      sqlite3Error(db, SQLITE_BUSY, 
        "Unable to delete/modify user-function due to active statements");
      assert( !db->mallocFailed );
      return SQLITE_BUSY;
    }else{
      sqlite3ExpirePreparedStatements(db);
    }
  }

  p = sqlite3FindFunction(db, zFunctionName, nName, nArg, enc, 1);
................................................................................
  int enc,
  void *p,
  void (*xFunc)(sqlite3_context*,int,sqlite3_value **),
  void (*xStep)(sqlite3_context*,int,sqlite3_value **),
  void (*xFinal)(sqlite3_context*)
){
  int rc;
  assert( !db->mallocFailed );
  rc = sqlite3CreateFunc(db, zFunctionName, nArg, enc, p, xFunc, xStep, xFinal);

  return sqlite3ApiExit(db, rc);
}

#ifndef SQLITE_OMIT_UTF16
int sqlite3_create_function16(
................................................................................
  void *p,
  void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
  void (*xStep)(sqlite3_context*,int,sqlite3_value**),
  void (*xFinal)(sqlite3_context*)
){
  int rc;
  char *zFunc8;
  assert( !db->mallocFailed );

  zFunc8 = sqlite3Utf16to8(zFunctionName, -1);
  rc = sqlite3CreateFunc(db, zFunc8, nArg, eTextRep, p, xFunc, xStep, xFinal);
  sqlite3_free(zFunc8);

  return sqlite3ApiExit(db, rc);
}
#endif


/*
................................................................................

/*
** Return UTF-8 encoded English language explanation of the most recent
** error.
*/
const char *sqlite3_errmsg(sqlite3 *db){
  const char *z;

  if( !db ){
    return sqlite3ErrStr(SQLITE_NOMEM);
  }
  assert( !db->mallocFailed );
  if( sqlite3SafetyCheck(db) || db->errCode==SQLITE_MISUSE ){
    return sqlite3ErrStr(SQLITE_MISUSE);
  }
  z = (char*)sqlite3_value_text(db->pErr);
  if( z==0 ){
    z = sqlite3ErrStr(db->errCode);
  }
................................................................................
    0, 'c', 0, 'a', 0, 'l', 0, 'l', 0, 'e', 0, 'd', 0, ' ', 
    0, 'o', 0, 'u', 0, 't', 0, ' ', 
    0, 'o', 0, 'f', 0, ' ', 
    0, 's', 0, 'e', 0, 'q', 0, 'u', 0, 'e', 0, 'n', 0, 'c', 0, 'e', 0, 0, 0
  };

  const void *z;
  assert( !db->mallocFailed );
  if( !db ){
    return (void *)(&outOfMemBe[SQLITE_UTF16NATIVE==SQLITE_UTF16LE?1:0]);
  }
  if( sqlite3SafetyCheck(db) || db->errCode==SQLITE_MISUSE ){
    return (void *)(&misuseBe[SQLITE_UTF16NATIVE==SQLITE_UTF16LE?1:0]);
  }
  z = sqlite3_value_text16(db->pErr);
................................................................................
#endif /* SQLITE_OMIT_UTF16 */

/*
** Return the most recent error code generated by an SQLite routine. If NULL is
** passed to this function, we assume a malloc() failed during sqlite3_open().
*/
int sqlite3_errcode(sqlite3 *db){
  if( !db || db->mallocFailed ){
    return SQLITE_NOMEM;
  }
  if( sqlite3SafetyCheck(db) ){
    return SQLITE_MISUSE;
  }
  return db->errCode & db->errMask;
}
................................................................................
  const char *zFilename, /* Database filename UTF-8 encoded */
  sqlite3 **ppDb         /* OUT: Returned database handle */
){
  sqlite3 *db;
  int rc;
  CollSeq *pColl;



  /* Allocate the sqlite data structure */
  db = sqlite3MallocZero( sizeof(sqlite3) );
  if( db==0 ) goto opendb_out;
  db->errMask = 0xff;
  db->priorNewRowid = 0;
  db->magic = SQLITE_MAGIC_BUSY;
  db->nDb = 2;
  db->aDb = db->aDbStatic;
  db->autoCommit = 1;
................................................................................
  ** conversions. The only error that can occur here is a malloc() failure.
  */
  if( createCollation(db, "BINARY", SQLITE_UTF8, 0, binCollFunc, 0) ||
      createCollation(db, "BINARY", SQLITE_UTF16BE, 0, binCollFunc, 0) ||
      createCollation(db, "BINARY", SQLITE_UTF16LE, 0, binCollFunc, 0) ||
      (db->pDfltColl = sqlite3FindCollSeq(db, SQLITE_UTF8, "BINARY", 6, 0))==0 
  ){
    assert( db->mallocFailed );
    db->magic = SQLITE_MAGIC_CLOSED;
    goto opendb_out;
  }

  /* Also add a UTF-8 case-insensitive collation sequence. */
  createCollation(db, "NOCASE", SQLITE_UTF8, 0, nocaseCollatingFunc, 0);

................................................................................
  rc = sqlite3BtreeFactory(db, zFilename, 0, SQLITE_DEFAULT_CACHE_SIZE,
                           &db->aDb[0].pBt);
  if( rc!=SQLITE_OK ){
    sqlite3Error(db, rc, 0);
    db->magic = SQLITE_MAGIC_CLOSED;
    goto opendb_out;
  }
  db->aDb[0].pSchema = sqlite3SchemaGet(db, db->aDb[0].pBt);
  db->aDb[1].pSchema = sqlite3SchemaGet(db, 0);


  /* The default safety_level for the main database is 'full'; for the temp
  ** database it is 'NONE'. This matches the pager layer defaults.  
  */
  db->aDb[0].zName = "main";
  db->aDb[0].safety_level = 3;
#ifndef SQLITE_OMIT_TEMPDB
  db->aDb[1].zName = "temp";
  db->aDb[1].safety_level = 1;
#endif

  db->magic = SQLITE_MAGIC_OPEN;
  if( db->mallocFailed ){
    goto opendb_out;
  }

  /* Register all built-in functions, but do not attempt to read the
  ** database schema yet. This is delayed until the first time the database
  ** is accessed.
  */
................................................................................
  */
  (void)sqlite3AutoLoadExtensions(db);
  if( sqlite3_errcode(db)!=SQLITE_OK ){
    goto opendb_out;
  }

#ifdef SQLITE_ENABLE_FTS1
  if( !db->mallocFailed ){
    extern int sqlite3Fts1Init(sqlite3*);
    rc = sqlite3Fts1Init(db);
  }
#endif

#ifdef SQLITE_ENABLE_FTS2
  if( !db->mallocFailed && rc==SQLITE_OK ){
    extern int sqlite3Fts2Init(sqlite3*);
    rc = sqlite3Fts2Init(db);
  }
#endif

#ifdef SQLITE_ENABLE_ICU
  if( !db->mallocFailed && rc==SQLITE_OK ){
    extern int sqlite3IcuInit(sqlite3*);
    rc = sqlite3IcuInit(db);
  }
#endif
  sqlite3Error(db, rc, 0);

  /* -DSQLITE_DEFAULT_LOCKING_MODE=1 makes EXCLUSIVE the default locking
................................................................................
  sqlite3* db, 
  const char *zName, 
  int enc, 
  void* pCtx,
  int(*xCompare)(void*,int,const void*,int,const void*)
){
  int rc;
  assert( !db->mallocFailed );
  rc = createCollation(db, zName, enc, pCtx, xCompare, 0);
  return sqlite3ApiExit(db, rc);
}

/*
** Register a new collation sequence with the database handle db.
*/
................................................................................
  const char *zName, 
  int enc, 
  void* pCtx,
  int(*xCompare)(void*,int,const void*,int,const void*),
  void(*xDel)(void*)
){
  int rc;
  assert( !db->mallocFailed );
  rc = createCollation(db, zName, enc, pCtx, xCompare, xDel);
  return sqlite3ApiExit(db, rc);
}

#ifndef SQLITE_OMIT_UTF16
/*
** Register a new collation sequence with the database handle db.
................................................................................
  const char *zName, 
  int enc, 
  void* pCtx,
  int(*xCompare)(void*,int,const void*,int,const void*)
){
  int rc = SQLITE_OK;
  char *zName8; 
  assert( !db->mallocFailed );
  zName8 = sqlite3Utf16to8(zName, -1);
  if( zName8 ){
    rc = createCollation(db, zName8, enc, pCtx, xCompare, 0);
    sqlite3_free(zName8);
  }
  return sqlite3ApiExit(db, rc);
}
#endif /* SQLITE_OMIT_UTF16 */

/*
** Register a collation sequence factory callback with the database handle
................................................................................

  if( SQLITE_OK==rc && !pTab ){
    sqlite3SetString(&zErrMsg, "no such table column: ", zTableName, ".", 
        zColumnName, 0);
    rc = SQLITE_ERROR;
  }
  sqlite3Error(db, rc, (zErrMsg?"%s":0), zErrMsg);
  sqlite3_free(zErrMsg);
  return sqlite3ApiExit(db, rc);
}
#endif

/*
** Set all the parameters in the compiled SQL statement to NULL.
*/

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** Memory allocation functions used throughout sqlite.
**
**
** $Id: malloc.c,v 1.4 2007/08/08 01:04:52 drh Exp $
*/
#include "sqliteInt.h"
#include "os.h"
#include <stdarg.h>
#include <ctype.h>

/*
** MALLOC WRAPPER ARCHITECTURE
**
** The sqlite code accesses dynamic memory allocation/deallocation by invoking
** the following six APIs (which may be implemented as macros).
**
**     sqlite3Malloc()
**     sqlite3MallocRaw()
**     sqlite3Realloc()
**     sqlite3ReallocOrFree()
**     sqlite3Free()
**     sqlite3AllocSize()
**
** The function sqlite3FreeX performs the same task as sqlite3Free and is
** guaranteed to be a real function. The same holds for sqlite3MallocX
**
** The above APIs are implemented in terms of the functions provided in the
** operating-system interface. The OS interface is never accessed directly
** by code outside of this file.
**
**     sqlite3OsMalloc()
**     sqlite3OsRealloc()
**     sqlite3OsFree()
**     sqlite3OsAllocationSize()
**
** Functions sqlite3MallocRaw() and sqlite3Realloc() may invoke 
** sqlite3_release_memory() if a call to sqlite3OsMalloc() or
** sqlite3OsRealloc() fails (or if the soft-heap-limit for the thread is
** exceeded). Function sqlite3Malloc() usually invokes
** sqlite3MallocRaw().
**
** MALLOC TEST WRAPPER ARCHITECTURE
**
** The test wrapper provides extra test facilities to ensure the library 
** does not leak memory and handles the failure of the underlying OS level
** allocation system correctly. It is only present if the library is 
** compiled with the SQLITE_MEMDEBUG macro set.
**
**     * Guardposts to detect overwrites.
**     * Ability to cause a specific Malloc() or Realloc() to fail.
**     * Audit outstanding memory allocations (i.e check for leaks).
*/

#define MAX(x,y) ((x)>(y)?(x):(y))

#if defined(SQLITE_ENABLE_MEMORY_MANAGEMENT) && !defined(SQLITE_OMIT_DISKIO)
/*
** Set the soft heap-size limit for the current thread. Passing a negative
** value indicates no limit.
*/
void sqlite3_soft_heap_limit(int n){
  ThreadData *pTd = sqlite3ThreadData();
  if( pTd ){
    pTd->nSoftHeapLimit = n;
................................................................................

/*
** Release memory held by SQLite instances created by the current thread.
*/
int sqlite3_release_memory(int n){
  return sqlite3PagerReleaseMemory(n);
}
#else
/* If SQLITE_ENABLE_MEMORY_MANAGEMENT is not defined, then define a version
** of sqlite3_release_memory() to be used by other code in this file.
** This is done for no better reason than to reduce the number of 
** pre-processor #ifndef statements.
*/
#define sqlite3_release_memory(x) 0    /* 0 == no memory freed */
#endif

#ifdef SQLITE_MEMDEBUG
/*--------------------------------------------------------------------------
** Begin code for memory allocation system test layer.
**
** Memory debugging is turned on by defining the SQLITE_MEMDEBUG macro.
**
** SQLITE_MEMDEBUG==1    -> Fence-posting only (thread safe) 
** SQLITE_MEMDEBUG==2    -> Fence-posting + linked list of allocations (not ts)
** SQLITE_MEMDEBUG==3    -> Above + backtraces (not thread safe, req. glibc)
*/

/* Figure out whether or not to store backtrace() information for each malloc.
** The backtrace() function is only used if SQLITE_MEMDEBUG is set to 2 or 
** greater and glibc is in use. If we don't want to use backtrace(), then just
** define it as an empty macro and set the amount of space reserved to 0.
*/
#if defined(__GLIBC__) && SQLITE_MEMDEBUG>2
  extern int backtrace(void **, int);
  #define TESTALLOC_STACKSIZE 128
  #define TESTALLOC_STACKFRAMES ((TESTALLOC_STACKSIZE-8)/sizeof(void*))
#else
  #define backtrace(x, y)
  #define TESTALLOC_STACKSIZE 0
  #define TESTALLOC_STACKFRAMES 0
#endif

/*
** Number of 32-bit guard words.  This should probably be a multiple of
** 2 since on 64-bit machines we want the value returned by sqliteMalloc()
** to be 8-byte aligned.

*/
#ifndef TESTALLOC_NGUARD
# define TESTALLOC_NGUARD 2
#endif

/*
** Size reserved for storing file-name along with each malloc()ed blob.
*/
#define TESTALLOC_FILESIZE 64

/*
** Size reserved for storing the user string. Each time a Malloc() or Realloc()
** call succeeds, up to TESTALLOC_USERSIZE bytes of the string pointed to by
** sqlite3_malloc_id are stored along with the other test system metadata.
*/
#define TESTALLOC_USERSIZE 64

const char *sqlite3_malloc_id = 0;



/*
** Blocks used by the test layer have the following format:
**
**        <sizeof(void *) pNext pointer>
**        <sizeof(void *) pPrev pointer>
**        <TESTALLOC_NGUARD 32-bit guard words>
**            <The application level allocation>
**        <TESTALLOC_NGUARD 32-bit guard words>
**        <32-bit line number>
**        <TESTALLOC_FILESIZE bytes containing null-terminated file name>
**        <TESTALLOC_STACKSIZE bytes of backtrace() output>
*/ 


#define TESTALLOC_OFFSET_GUARD1(p)    (sizeof(void *) * 2)
#define TESTALLOC_OFFSET_DATA(p) ( \
  TESTALLOC_OFFSET_GUARD1(p) + sizeof(u32) * TESTALLOC_NGUARD \
)
#define TESTALLOC_OFFSET_GUARD2(p) ( \
  TESTALLOC_OFFSET_DATA(p) + sqlite3OsAllocationSize(p) - TESTALLOC_OVERHEAD \
)
#define TESTALLOC_OFFSET_LINENUMBER(p) ( \
  TESTALLOC_OFFSET_GUARD2(p) + sizeof(u32) * TESTALLOC_NGUARD \
)
#define TESTALLOC_OFFSET_FILENAME(p) ( \
  TESTALLOC_OFFSET_LINENUMBER(p) + sizeof(u32) \
)
#define TESTALLOC_OFFSET_USER(p) ( \
  TESTALLOC_OFFSET_FILENAME(p) + TESTALLOC_FILESIZE \
)
#define TESTALLOC_OFFSET_STACK(p) ( \
  TESTALLOC_OFFSET_USER(p) + TESTALLOC_USERSIZE + 8 - \
  (TESTALLOC_OFFSET_USER(p) % 8) \
)

#define TESTALLOC_OVERHEAD ( \
  sizeof(void *)*2 +                   /* pPrev and pNext pointers */   \
  TESTALLOC_NGUARD*sizeof(u32)*2 +              /* Guard words */       \
  sizeof(u32) + TESTALLOC_FILESIZE +   /* File and line number */       \
  TESTALLOC_USERSIZE +                 /* User string */                \
  TESTALLOC_STACKSIZE                  /* backtrace() stack */          \
)


/*
** For keeping track of the number of mallocs and frees.   This
** is used to check for memory leaks.  The iMallocFail and iMallocReset
** values are used to simulate malloc() failures during testing in 
** order to verify that the library correctly handles an out-of-memory
** condition.


*/
int sqlite3_nMalloc;         /* Number of sqliteMalloc() calls */
int sqlite3_nFree;           /* Number of sqliteFree() calls */
int sqlite3_memUsed;         /* TODO Total memory obtained from malloc */
int sqlite3_memMax;          /* TODO Mem usage high-water mark */
int sqlite3_iMallocFail;     /* Fail sqliteMalloc() after this many calls */
int sqlite3_iMallocReset = -1; /* When iMallocFail reaches 0, set to this */

void *sqlite3_pFirst = 0;         /* Pointer to linked list of allocations */
int sqlite3_nMaxAlloc = 0;        /* High water mark of ThreadData.nAlloc */
int sqlite3_mallocDisallowed = 0; /* assert() in sqlite3Malloc() if set */
int sqlite3_isFail = 0;           /* True if all malloc calls should fail */
const char *sqlite3_zFile = 0;    /* Filename to associate debug info with */
int sqlite3_iLine = 0;            /* Line number for debug info */
int sqlite3_mallocfail_trace = 0; /* Print a msg on malloc fail if true */

/*
** Check for a simulated memory allocation failure.  Return true if
** the failure should be simulated.  Return false to proceed as normal.
*/
int sqlite3TestMallocFail(){

  if( sqlite3_isFail ){
    return 1;
  }
  if( sqlite3_iMallocFail>=0 ){



    sqlite3_iMallocFail--;
    if( sqlite3_iMallocFail==0 ){
      sqlite3_iMallocFail = sqlite3_iMallocReset;
      sqlite3_isFail = 1;
      if( sqlite3_mallocfail_trace ){
         sqlite3DebugPrintf("###_malloc_fails_###\n");
      }
      return 1;
    }
  }
  return 0;
}

/*
** The argument is a pointer returned by sqlite3OsMalloc() or xRealloc().
** assert() that the first and last (TESTALLOC_NGUARD*4) bytes are set to the
** values set by the applyGuards() function.
*/
static void checkGuards(u32 *p)
{
  int i;
  char *zAlloc = (char *)p;
  char *z;

  /* First set of guard words */
  z = &zAlloc[TESTALLOC_OFFSET_GUARD1(p)];
  for(i=0; i<TESTALLOC_NGUARD; i++){
    assert(((u32 *)z)[i]==0xdead1122);
  }

  /* Second set of guard words */
  z = &zAlloc[TESTALLOC_OFFSET_GUARD2(p)];
  for(i=0; i<TESTALLOC_NGUARD; i++){
    u32 guard = 0;
    memcpy(&guard, &z[i*sizeof(u32)], sizeof(u32));
    assert(guard==0xdead3344);
  }
}

/*
** The argument is a pointer returned by sqlite3OsMalloc() or Realloc(). The
** first and last (TESTALLOC_NGUARD*4) bytes are set to known values for use as 
** guard-posts.
*/
static void applyGuards(u32 *p)
{
  int i;
  char *z;
  char *zAlloc = (char *)p;

  /* First set of guard words */
  z = &zAlloc[TESTALLOC_OFFSET_GUARD1(p)];
  for(i=0; i<TESTALLOC_NGUARD; i++){
    ((u32 *)z)[i] = 0xdead1122;
  }

  /* Second set of guard words */
  z = &zAlloc[TESTALLOC_OFFSET_GUARD2(p)];
  for(i=0; i<TESTALLOC_NGUARD; i++){
    static const int guard = 0xdead3344;
    memcpy(&z[i*sizeof(u32)], &guard, sizeof(u32));
  }

  /* Line number */
  z = &((char *)z)[TESTALLOC_NGUARD*sizeof(u32)];             /* Guard words */
  z = &zAlloc[TESTALLOC_OFFSET_LINENUMBER(p)];
  memcpy(z, &sqlite3_iLine, sizeof(u32));

  /* File name */
  z = &zAlloc[TESTALLOC_OFFSET_FILENAME(p)];
  strncpy(z, sqlite3_zFile, TESTALLOC_FILESIZE);
  z[TESTALLOC_FILESIZE - 1] = '\0';

  /* User string */
  z = &zAlloc[TESTALLOC_OFFSET_USER(p)];
  z[0] = 0;

  if( sqlite3_malloc_id ){
    strncpy(z, sqlite3_malloc_id, TESTALLOC_USERSIZE);
    z[TESTALLOC_USERSIZE-1] = 0;
  }

  /* backtrace() stack */
  z = &zAlloc[TESTALLOC_OFFSET_STACK(p)];
  backtrace((void **)z, TESTALLOC_STACKFRAMES);

  /* Sanity check to make sure checkGuards() is working */
  checkGuards(p);
}

/*
** The argument is a malloc()ed pointer as returned by the test-wrapper.
** Return a pointer to the Os level allocation.
*/
static void *getOsPointer(void *p)
{
  char *z = (char *)p;
  return (void *)(&z[-1 * TESTALLOC_OFFSET_DATA(p)]);
}


#if SQLITE_MEMDEBUG>1
/*
** The argument points to an Os level allocation. Link it into the threads list
** of allocations.
*/
static void linkAlloc(void *p){
  void **pp = (void **)p;
  pp[0] = 0;
  pp[1] = sqlite3_pFirst;
  if( sqlite3_pFirst ){
    ((void **)sqlite3_pFirst)[0] = p;
  }
  sqlite3_pFirst = p;
}

/*
** The argument points to an Os level allocation. Unlinke it from the threads
** list of allocations.
*/
static void unlinkAlloc(void *p)
{
  void **pp = (void **)p;
  if( p==sqlite3_pFirst ){
    assert(!pp[0]);
    assert(!pp[1] || ((void **)(pp[1]))[0]==p);
    sqlite3_pFirst = pp[1];
    if( sqlite3_pFirst ){
      ((void **)sqlite3_pFirst)[0] = 0;
    }
  }else{
    void **pprev = pp[0];
    void **pnext = pp[1];
    assert(pprev);
    assert(pprev[1]==p);
    pprev[1] = (void *)pnext;
    if( pnext ){
      assert(pnext[0]==p);
      pnext[0] = (void *)pprev;
    }
  }
}

/*
** Pointer p is a pointer to an OS level allocation that has just been
** realloc()ed. Set the list pointers that point to this entry to it's new
** location.
*/
static void relinkAlloc(void *p)
{
  void **pp = (void **)p;
  if( pp[0] ){
    ((void **)(pp[0]))[1] = p;
  }else{
    sqlite3_pFirst = p;
  }
  if( pp[1] ){
    ((void **)(pp[1]))[0] = p;
  }
}
#else
#define linkAlloc(x)
#define relinkAlloc(x)
#define unlinkAlloc(x)
#endif

/*
** This function sets the result of the Tcl interpreter passed as an argument
** to a list containing an entry for each currently outstanding call made to 
** sqliteMalloc and friends by the current thread. Each list entry is itself a
** list, consisting of the following (in order):
**
**     * The number of bytes allocated
**     * The __FILE__ macro at the time of the sqliteMalloc() call.
**     * The __LINE__ macro ...
**     * The value of the sqlite3_malloc_id variable ...
**     * The output of backtrace() (if available) ...
**
** Todo: We could have a version of this function that outputs to stdout, 
** to debug memory leaks when Tcl is not available.
*/
#if defined(TCLSH) && defined(SQLITE_DEBUG) && SQLITE_MEMDEBUG>1
#include <tcl.h>
int sqlite3OutstandingMallocs(Tcl_Interp *interp){
  void *p;
  Tcl_Obj *pRes = Tcl_NewObj();
  Tcl_IncrRefCount(pRes);


  for(p=sqlite3_pFirst; p; p=((void **)p)[1]){
    Tcl_Obj *pEntry = Tcl_NewObj();
    Tcl_Obj *pStack = Tcl_NewObj();
    char *z;
    u32 iLine;
    int nBytes = sqlite3OsAllocationSize(p) - TESTALLOC_OVERHEAD;
    char *zAlloc = (char *)p;
    int i;

    Tcl_ListObjAppendElement(0, pEntry, Tcl_NewIntObj(nBytes));

    z = &zAlloc[TESTALLOC_OFFSET_FILENAME(p)];
    Tcl_ListObjAppendElement(0, pEntry, Tcl_NewStringObj(z, -1));

    z = &zAlloc[TESTALLOC_OFFSET_LINENUMBER(p)];
    memcpy(&iLine, z, sizeof(u32));
    Tcl_ListObjAppendElement(0, pEntry, Tcl_NewIntObj(iLine));

    z = &zAlloc[TESTALLOC_OFFSET_USER(p)];
    Tcl_ListObjAppendElement(0, pEntry, Tcl_NewStringObj(z, -1));

    z = &zAlloc[TESTALLOC_OFFSET_STACK(p)];
    for(i=0; i<TESTALLOC_STACKFRAMES; i++){
      char zHex[128];
      sqlite3_snprintf(sizeof(zHex), zHex, "%p", ((void **)z)[i]);
      Tcl_ListObjAppendElement(0, pStack, Tcl_NewStringObj(zHex, -1));
    }

    Tcl_ListObjAppendElement(0, pEntry, pStack);
    Tcl_ListObjAppendElement(0, pRes, pEntry);
  }

  Tcl_ResetResult(interp);
  Tcl_SetObjResult(interp, pRes);
  Tcl_DecrRefCount(pRes);
  return TCL_OK;
}
#endif

/*
** This is the test layer's wrapper around sqlite3OsMalloc().
*/
static void * OSMALLOC(int n){
  sqlite3OsEnterMutex();
#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
  sqlite3_nMaxAlloc = 
      MAX(sqlite3_nMaxAlloc, sqlite3ThreadDataReadOnly()->nAlloc);
#endif
  assert( !sqlite3_mallocDisallowed );
  if( !sqlite3TestMallocFail() ){
    u32 *p;
    p = (u32 *)sqlite3OsMalloc(n + TESTALLOC_OVERHEAD);
    assert(p);
    sqlite3_nMalloc++;
    applyGuards(p);
    linkAlloc(p);
    sqlite3OsLeaveMutex();
    return (void *)(&p[TESTALLOC_NGUARD + 2*sizeof(void *)/sizeof(u32)]);
  }
  sqlite3OsLeaveMutex();
  return 0;
}

static int OSSIZEOF(void *p){
  if( p ){
    u32 *pOs = (u32 *)getOsPointer(p);
    return sqlite3OsAllocationSize(pOs) - TESTALLOC_OVERHEAD;
  }
  return 0;
}

/*
** This is the test layer's wrapper around sqlite3OsFree(). The argument is a
** pointer to the space allocated for the application to use.
*/
static void OSFREE(void *pFree){
  u32 *p;         /* Pointer to the OS-layer allocation */
  sqlite3OsEnterMutex();
  p = (u32 *)getOsPointer(pFree);
  checkGuards(p);
  unlinkAlloc(p);
  memset(pFree, 0x55, OSSIZEOF(pFree));
  sqlite3OsFree(p);
  sqlite3_nFree++;
  sqlite3OsLeaveMutex();
}

/*
** This is the test layer's wrapper around sqlite3OsRealloc().
*/
static void * OSREALLOC(void *pRealloc, int n){
#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
  sqlite3_nMaxAlloc = 
      MAX(sqlite3_nMaxAlloc, sqlite3ThreadDataReadOnly()->nAlloc);
#endif
  assert( !sqlite3_mallocDisallowed );
  if( !sqlite3TestMallocFail() ){
    u32 *p = (u32 *)getOsPointer(pRealloc);
    checkGuards(p);
    p = sqlite3OsRealloc(p, n + TESTALLOC_OVERHEAD);
    applyGuards(p);
    relinkAlloc(p);
    return (void *)(&p[TESTALLOC_NGUARD + 2*sizeof(void *)/sizeof(u32)]);
  }
  return 0;
}

static void OSMALLOC_FAILED(){
  sqlite3_isFail = 0;
}

#else
/* Define macros to call the sqlite3OsXXX interface directly if 
** the SQLITE_MEMDEBUG macro is not defined.
*/
#define OSMALLOC(x)        sqlite3OsMalloc(x)
#define OSREALLOC(x,y)     sqlite3OsRealloc(x,y)
#define OSFREE(x)          sqlite3OsFree(x)
#define OSSIZEOF(x)        sqlite3OsAllocationSize(x)
#define OSMALLOC_FAILED()

#endif  /* SQLITE_MEMDEBUG */
/*
** End code for memory allocation system test layer.
**--------------------------------------------------------------------------*/

/*
** This routine is called when we are about to allocate n additional bytes
** of memory.  If the new allocation will put is over the soft allocation
** limit, then invoke sqlite3_release_memory() to try to release some
** memory before continuing with the allocation.
**
** This routine also makes sure that the thread-specific-data (TSD) has
** be allocated.  If it has not and can not be allocated, then return
** false.  The updateMemoryUsedCount() routine below will deallocate
** the TSD if it ought to be.
**
** If SQLITE_ENABLE_MEMORY_MANAGEMENT is not defined, this routine is
** a no-op
*/ 
#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
static int enforceSoftLimit(int n){
  ThreadData *pTsd = sqlite3ThreadData();
  if( pTsd==0 ){
    return 0;
  }
  assert( pTsd->nAlloc>=0 );
  if( n>0 && pTsd->nSoftHeapLimit>0 ){
    while( pTsd->nAlloc+n>pTsd->nSoftHeapLimit && sqlite3_release_memory(n) ){}
  }
  return 1;
}
#else
# define enforceSoftLimit(X)  1
#endif

/*
** Update the count of total outstanding memory that is held in
** thread-specific-data (TSD).  If after this update the TSD is
** no longer being used, then deallocate it.
**
** If SQLITE_ENABLE_MEMORY_MANAGEMENT is not defined, this routine is
** a no-op
*/
#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
static void updateMemoryUsedCount(int n){
  ThreadData *pTsd = sqlite3ThreadData();
  if( pTsd ){
    pTsd->nAlloc += n;
    assert( pTsd->nAlloc>=0 );
    if( pTsd->nAlloc==0 && pTsd->nSoftHeapLimit==0 ){
      sqlite3ReleaseThreadData();
    }
  }
}
#else
#define updateMemoryUsedCount(x)  /* no-op */
#endif

/*
** Allocate and return N bytes of uninitialised memory by calling
** sqlite3OsMalloc(). If the Malloc() call fails, attempt to free memory 
** by calling sqlite3_release_memory().
*/
void *sqlite3MallocRaw(int n, int doMemManage){
  void *p = 0;
  if( n>0 && !sqlite3MallocFailed() && (!doMemManage || enforceSoftLimit(n)) ){
    while( (p = OSMALLOC(n))==0 && sqlite3_release_memory(n) ){}
    if( !p ){
      sqlite3FailedMalloc();
      OSMALLOC_FAILED();
    }else if( doMemManage ){
      updateMemoryUsedCount(OSSIZEOF(p));
    }
  }
  return p;
}

/*
** Resize the allocation at p to n bytes by calling sqlite3OsRealloc(). The
** pointer to the new allocation is returned.  If the Realloc() call fails,
** attempt to free memory by calling sqlite3_release_memory().
*/
void *sqlite3Realloc(void *p, int n){
  if( sqlite3MallocFailed() ){
    return 0;
  }

  if( !p ){
    return sqlite3Malloc(n, 1);
  }else{
    void *np = 0;
#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
    int origSize = OSSIZEOF(p);
#endif
    if( enforceSoftLimit(n - origSize) ){
      while( (np = OSREALLOC(p, n))==0 && sqlite3_release_memory(n) ){}
      if( !np ){
        sqlite3FailedMalloc();
        OSMALLOC_FAILED();
      }else{
        updateMemoryUsedCount(OSSIZEOF(np) - origSize);
      }
    }
    return np;
  }
}

/*
** Free the memory pointed to by p. p must be either a NULL pointer or a 
** value returned by a previous call to sqlite3Malloc() or sqlite3Realloc().


*/
void sqlite3FreeX(void *p){
  if( p ){
    updateMemoryUsedCount(0 - OSSIZEOF(p));
    OSFREE(p);
  }
}

/*
** A version of sqliteMalloc() that is always a function, not a macro.
** Currently, this is used only to alloc to allocate the parser engine.
*/
void *sqlite3MallocX(int n){
  return sqliteMalloc(n);
}

/*
** sqlite3Malloc
** sqlite3ReallocOrFree
**
** These two are implemented as wrappers around sqlite3MallocRaw(), 
** sqlite3Realloc() and sqlite3Free().
*/ 
void *sqlite3Malloc(int n, int doMemManage){
  void *p = sqlite3MallocRaw(n, doMemManage);
  if( p ){
    memset(p, 0, n);
  }
  return p;
}
void *sqlite3ReallocOrFree(void *p, int n){

  void *pNew;
  pNew = sqlite3Realloc(p, n);
  if( !pNew ){
    sqlite3FreeX(p);

  }
  return pNew;
}

/*
** sqlite3ThreadSafeMalloc() and sqlite3ThreadSafeFree() are used in those
** rare scenarios where sqlite may allocate memory in one thread and free
** it in another. They are exactly the same as sqlite3Malloc() and 
** sqlite3Free() except that:
**
**   * The allocated memory is not included in any calculations with 
**     respect to the soft-heap-limit, and
**
**   * sqlite3ThreadSafeMalloc() must be matched with ThreadSafeFree(),
**     not sqlite3Free(). Calling sqlite3Free() on memory obtained from
**     ThreadSafeMalloc() will cause an error somewhere down the line.
*/
#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
void *sqlite3ThreadSafeMalloc(int n){
  (void)ENTER_MALLOC;
  return sqlite3Malloc(n, 0);
}
void sqlite3ThreadSafeFree(void *p){
  (void)ENTER_MALLOC;
  if( p ){
    OSFREE(p);
  }
}
#endif


/*
** Return the number of bytes allocated at location p. p must be either 
** a NULL pointer (in which case 0 is returned) or a pointer returned by 
** sqlite3Malloc(), sqlite3Realloc() or sqlite3ReallocOrFree().
**
** The number of bytes allocated does not include any overhead inserted by 
** any malloc() wrapper functions that may be called. So the value returned
** is the number of bytes that were available to SQLite using pointer p, 
** regardless of how much memory was actually allocated.
*/
#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
int sqlite3AllocSize(void *p){
  return OSSIZEOF(p);
}
#endif

/*
** Make a copy of a string in memory obtained from sqliteMalloc(). These 
** functions call sqlite3MallocRaw() directly instead of sqliteMalloc(). This
** is because when memory debugging is turned on, these two functions are 
** called via macros that record the current file and line number in the
** ThreadData structure.
................................................................................
  zResult[0] = 0;
  va_end(ap);
}


/*
** This function must be called before exiting any API function (i.e. 
** returning control to the user) that has called sqlite3Malloc or
** sqlite3Realloc.
**
** The returned value is normally a copy of the second argument to this
** function. However, if a malloc() failure has occured since the previous
** invocation SQLITE_NOMEM is returned instead. 
**
** If the first argument, db, is not NULL and a malloc() error has occured,
** then the connection error-code (the value returned by sqlite3_errcode())
** is set to SQLITE_NOMEM.
*/
int sqlite3MallocHasFailed = 0;
int sqlite3ApiExit(sqlite3* db, int rc){
  if( sqlite3MallocFailed() ){
    sqlite3MallocHasFailed = 0;
    sqlite3OsLeaveMutex();
    sqlite3Error(db, SQLITE_NOMEM, 0);

    rc = SQLITE_NOMEM;
  }
  return rc & (db ? db->errMask : 0xff);
}

/* 
** Set the "malloc has failed" condition to true for this thread.
*/
void sqlite3FailedMalloc(){
  if( !sqlite3MallocFailed() ){
    sqlite3OsEnterMutex();
    assert( sqlite3MallocHasFailed==0 );
    sqlite3MallocHasFailed = 1;
  }
}

#ifdef SQLITE_MEMDEBUG
/*
** This function sets a flag in the thread-specific-data structure that will
** cause an assert to fail if sqliteMalloc() or sqliteRealloc() is called.
*/
void sqlite3MallocDisallow(){

  assert( sqlite3_mallocDisallowed>=0 );
  sqlite3_mallocDisallowed++;

}

/*
** This function clears the flag set in the thread-specific-data structure set
** by sqlite3MallocDisallow().
*/
void sqlite3MallocAllow(){

  assert( sqlite3_mallocDisallowed>0 );
  sqlite3_mallocDisallowed--;

}
#endif

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** Memory allocation functions used throughout sqlite.
**
**
** $Id: malloc.c,v 1.5 2007/08/16 04:30:40 drh Exp $
*/
#include "sqliteInt.h"
#include "os.h"
#include <stdarg.h>
#include <ctype.h>

/*














































** Set the soft heap-size limit for the current thread. Passing a negative
** value indicates no limit.
*/
void sqlite3_soft_heap_limit(int n){
  ThreadData *pTd = sqlite3ThreadData();
  if( pTd ){
    pTd->nSoftHeapLimit = n;
................................................................................

/*
** Release memory held by SQLite instances created by the current thread.
*/
int sqlite3_release_memory(int n){
  return sqlite3PagerReleaseMemory(n);
}



































/*



** Allocate and zero memory.
*/ 















void *sqlite3MallocZero(unsigned n){
  void *p = sqlite3_malloc(n);
  if( p ){
    memset(p, 0, n);
  }












  return p;
}






























/*





** Allocate and zero memory.  If the allocation fails, make
** the mallocFailed flag in the connection pointer.
*/




















void *sqlite3DbMallocZero(sqlite3 *db, unsigned n){
  void *p = sqlite3_malloc(n);



  if( p ){
    memset(p, 0, n);
  }else{
    db->mallocFailed = 1;





  }
  return p;



}

/*
** Allocate and zero memory.  If the allocation fails, make
** the mallocFailed flag in the connection pointer.

*/


























































void *sqlite3DbMallocRaw(sqlite3 *db, unsigned n){
  void *p = sqlite3_malloc(n);











































































































































































































































































































  if( !p ){















    db->mallocFailed = 1;

  }

















  return p;
}


/*


** Attempt to reallocate p.  If the reallocation fails, then free p
** and set the mallocFailed flag in the database connection.
*/






























void *sqlite3DbReallocOrFree(sqlite3 *db, void *p, int n){
  void *pNew;
  pNew = sqlite3_realloc(p, n);
  if( !pNew ){
    sqlite3FreeX(p);
    db->mallocFailed = 1;
  }
  return pNew;
}












































/*
** Make a copy of a string in memory obtained from sqliteMalloc(). These 
** functions call sqlite3MallocRaw() directly instead of sqliteMalloc(). This
** is because when memory debugging is turned on, these two functions are 
** called via macros that record the current file and line number in the
** ThreadData structure.
................................................................................
  zResult[0] = 0;
  va_end(ap);
}


/*
** This function must be called before exiting any API function (i.e. 
** returning control to the user) that has called sqlite3_malloc or
** sqlite3_realloc.
**
** The returned value is normally a copy of the second argument to this
** function. However, if a malloc() failure has occured since the previous
** invocation SQLITE_NOMEM is returned instead. 
**
** If the first argument, db, is not NULL and a malloc() error has occured,
** then the connection error-code (the value returned by sqlite3_errcode())
** is set to SQLITE_NOMEM.
*/

int sqlite3ApiExit(sqlite3* db, int rc){
  if( db->mallocFailed ){


    sqlite3Error(db, SQLITE_NOMEM, 0);
    db->mallocFailed = 0;
    rc = SQLITE_NOMEM;
  }
  return rc & (db ? db->errMask : 0xff);
}












#ifdef SQLITE_MEMDEBUG
/*
** This function sets a flag in the thread-specific-data structure that will
** cause an assert to fail if sqliteMalloc() or sqliteRealloc() is called.
*/
void sqlite3MallocDisallow(){
#if 0
  assert( sqlite3_mallocDisallowed>=0 );
  sqlite3_mallocDisallowed++;
#endif
}

/*
** This function clears the flag set in the thread-specific-data structure set
** by sqlite3MallocDisallow().
*/
void sqlite3MallocAllow(){
#if 0
  assert( sqlite3_mallocDisallowed>0 );
  sqlite3_mallocDisallowed--;
#endif
}
#endif

};

/* 
** These hash tables map inodes and file descriptors (really, lockKey and
** openKey structures) into lockInfo and openCnt structures.  Access to 
** these hash tables must be protected by a mutex.
*/
static Hash lockHash = {SQLITE_HASH_BINARY, 0, 0, 0, 
    sqlite3ThreadSafeMalloc, sqlite3ThreadSafeFree, 0, 0};
static Hash openHash = {SQLITE_HASH_BINARY, 0, 0, 0, 
    sqlite3ThreadSafeMalloc, sqlite3ThreadSafeFree, 0, 0};

#ifdef SQLITE_ENABLE_LOCKING_STYLE
/*
** The locking styles are associated with the different file locking
** capabilities supported by different file systems.  
**
** POSIX locking style fully supports shared and exclusive byte-range locks 
................................................................................
static void releaseLockInfo(struct lockInfo *pLock){
  assert( sqlite3OsInMutex(1) );
  if (pLock == NULL)
    return;
  pLock->nRef--;
  if( pLock->nRef==0 ){
    sqlite3HashInsert(&lockHash, &pLock->key, sizeof(pLock->key), 0);
    sqlite3ThreadSafeFree(pLock);
  }
}

/*
** Release a openCnt structure previously allocated by findLockInfo().
*/
static void releaseOpenCnt(struct openCnt *pOpen){
................................................................................
  assert( sqlite3OsInMutex(1) );
  if (pOpen == NULL)
    return;
  pOpen->nRef--;
  if( pOpen->nRef==0 ){
    sqlite3HashInsert(&openHash, &pOpen->key, sizeof(pOpen->key), 0);
    free(pOpen->aPending);
    sqlite3ThreadSafeFree(pOpen);
  }
}

#ifdef SQLITE_ENABLE_LOCKING_STYLE
/*
** Tests a byte-range locking query to see if byte range locks are 
** supported, if not we fall back to dotlockLockingStyle.
................................................................................
#endif
  memset(&key2, 0, sizeof(key2));
  key2.dev = statbuf.st_dev;
  key2.ino = statbuf.st_ino;
  pLock = (struct lockInfo*)sqlite3HashFind(&lockHash, &key1, sizeof(key1));
  if( pLock==0 ){
    struct lockInfo *pOld;
    pLock = sqlite3ThreadSafeMalloc( sizeof(*pLock) );
    if( pLock==0 ){
      rc = 1;
      goto exit_findlockinfo;
    }
    pLock->key = key1;
    pLock->nRef = 1;
    pLock->cnt = 0;
    pLock->locktype = 0;
    pOld = sqlite3HashInsert(&lockHash, &pLock->key, sizeof(key1), pLock);
    if( pOld!=0 ){
      assert( pOld==pLock );
      sqlite3ThreadSafeFree(pLock);
      rc = 1;
      goto exit_findlockinfo;
    }
  }else{
    pLock->nRef++;
  }
  *ppLock = pLock;
  if( ppOpen!=0 ){
    pOpen = (struct openCnt*)sqlite3HashFind(&openHash, &key2, sizeof(key2));
    if( pOpen==0 ){
      struct openCnt *pOld;
      pOpen = sqlite3ThreadSafeMalloc( sizeof(*pOpen) );
      if( pOpen==0 ){
        releaseLockInfo(pLock);
        rc = 1;
        goto exit_findlockinfo;
      }
      pOpen->key = key2;
      pOpen->nRef = 1;
      pOpen->nLock = 0;
      pOpen->nPending = 0;
      pOpen->aPending = 0;
      pOld = sqlite3HashInsert(&openHash, &pOpen->key, sizeof(key2), pOpen);
      if( pOld!=0 ){
        assert( pOld==pOpen );
        sqlite3ThreadSafeFree(pOpen);
        releaseLockInfo(pLock);
        rc = 1;
        goto exit_findlockinfo;
      }
    }else{
      pOpen->nRef++;
    }
................................................................................
  releaseLockInfo(pFile->pLock);
  releaseOpenCnt(pFile->pOpen);

  sqlite3OsLeaveMutex();
  pFile->isOpen = 0;
  OSTRACE2("CLOSE   %-3d\n", pFile->h);
  OpenCounter(-1);
  sqlite3ThreadSafeFree(id);
  return SQLITE_OK;
}


#ifdef SQLITE_ENABLE_LOCKING_STYLE
#pragma mark AFP Support

................................................................................
  unixFile *id = (unixFile*)*pId;
  
  if( !id ) return SQLITE_OK;
  afpUnixUnlock(*pId, NO_LOCK);
  /* free the AFP locking structure */
  if (id->lockingContext != NULL) {
    if (((afpLockingContext *)id->lockingContext)->filePath != NULL)
      sqlite3ThreadSafeFree(((afpLockingContext*)id->lockingContext)->filePath);
    sqlite3ThreadSafeFree(id->lockingContext);
  }
  
  if( id->dirfd>=0 ) close(id->dirfd);
  id->dirfd = -1;
  close(id->h);
  id->isOpen = 0;
  OSTRACE2("CLOSE   %-3d\n", id->h);
  OpenCounter(-1);
  sqlite3ThreadSafeFree(id);
  *pId = 0;
  return SQLITE_OK;
}


#pragma mark flock() style locking

................................................................................
  sqlite3OsEnterMutex();
  
  close(id->h);  
  sqlite3OsLeaveMutex();
  id->isOpen = 0;
  OSTRACE2("CLOSE   %-3d\n", id->h);
  OpenCounter(-1);
  sqlite3ThreadSafeFree(id);
  *pId = 0;
  return SQLITE_OK;
}

#pragma mark Old-School .lock file based locking

/*
................................................................................
  unixFile *id = (unixFile*)*pId;
  
  if( !id ) return SQLITE_OK;
  dotlockUnixUnlock(*pId, NO_LOCK);
  /* free the dotlock locking structure */
  if (id->lockingContext != NULL) {
    if (((dotlockLockingContext *)id->lockingContext)->lockPath != NULL)
      sqlite3ThreadSafeFree( ( (dotlockLockingContext *)
        id->lockingContext)->lockPath);
    sqlite3ThreadSafeFree(id->lockingContext);
  }
  
  if( id->dirfd>=0 ) close(id->dirfd);
  id->dirfd = -1;
  sqlite3OsEnterMutex();
  
  close(id->h);
  
  sqlite3OsLeaveMutex();
  id->isOpen = 0;
  OSTRACE2("CLOSE   %-3d\n", id->h);
  OpenCounter(-1);
  sqlite3ThreadSafeFree(id);
  *pId = 0;
  return SQLITE_OK;
}


#pragma mark No locking

................................................................................
  
  close(id->h);
  
  sqlite3OsLeaveMutex();
  id->isOpen = 0;
  OSTRACE2("CLOSE   %-3d\n", id->h);
  OpenCounter(-1);
  sqlite3ThreadSafeFree(id);
  *pId = 0;
  return SQLITE_OK;
}

#endif /* SQLITE_ENABLE_LOCKING_STYLE */

/*
................................................................................
** is no longer needed.
*/
char *sqlite3UnixFullPathname(const char *zRelative){
  char *zFull = 0;
  if( zRelative[0]=='/' ){
    sqlite3SetString(&zFull, zRelative, (char*)0);
  }else{
    char *zBuf = sqliteMalloc(5000);
    if( zBuf==0 ){
      return 0;
    }
    zBuf[0] = 0;
    sqlite3SetString(&zFull, getcwd(zBuf, 5000), "/", zRelative,
                    (char*)0);
    sqliteFree(zBuf);
................................................................................
  }
  if( delFlag ){
    unlink(zFilename);
  }
  f.dirfd = -1;
  f.h = h;
  SET_THREADID(&f);
  pNew = sqlite3ThreadSafeMalloc( sizeof(unixFile) );
  if( pNew==0 ){
    close(h);
    sqlite3OsEnterMutex();
    releaseLockInfo(f.pLock);
    releaseOpenCnt(f.pOpen);
    sqlite3OsLeaveMutex();
    *pId = 0;
................................................................................
    switch(lockingStyle) {
      case afpLockingStyle: {
        /* afp locking uses the file path so it needs to be included in
        ** the afpLockingContext */
        int nFilename;
        pNew->pMethod = &sqlite3AFPLockingUnixIoMethod;
        pNew->lockingContext = 
          sqlite3ThreadSafeMalloc(sizeof(afpLockingContext));
        nFilename = strlen(zFilename)+1;
        ((afpLockingContext *)pNew->lockingContext)->filePath = 
          sqlite3ThreadSafeMalloc(nFilename);
        memcpy(((afpLockingContext *)pNew->lockingContext)->filePath, 
               zFilename, nFilename);
        srandomdev();
        break;
      }
      case flockLockingStyle:
        /* flock locking doesn't need additional lockingContext information */
................................................................................
        pNew->pMethod = &sqlite3FlockLockingUnixIoMethod;
        break;
      case dotlockLockingStyle: {
        /* dotlock locking uses the file path so it needs to be included in
         ** the dotlockLockingContext */
        int nFilename;
        pNew->pMethod = &sqlite3DotlockLockingUnixIoMethod;
        pNew->lockingContext = sqlite3ThreadSafeMalloc(
          sizeof(dotlockLockingContext));
        nFilename = strlen(zFilename) + 6;
        ((dotlockLockingContext *)pNew->lockingContext)->lockPath = 
            sqlite3ThreadSafeMalloc( nFilename );
        sqlite3_snprintf(nFilename, 
                ((dotlockLockingContext *)pNew->lockingContext)->lockPath, 
                "%s.lock", zFilename);
        break;
      }
      case posixLockingStyle:
        /* posix locking doesn't need additional lockingContext information */
................................................................................
    close(h);
    return SQLITE_NOMEM;
  }
  OSTRACE3("OPEN    %-3d %s\n", h, zFilename);
  f.dirfd = -1;
  f.h = h;
  SET_THREADID(&f);
  pNew = sqlite3ThreadSafeMalloc( sizeof(unixFile) );
  if( pNew==0 ){
    close(h);
    sqlite3OsEnterMutex();
    releaseLockInfo(f.pLock);
    releaseOpenCnt(f.pOpen);
    sqlite3OsLeaveMutex();
    *pId = 0;

};

/* 
** These hash tables map inodes and file descriptors (really, lockKey and
** openKey structures) into lockInfo and openCnt structures.  Access to 
** these hash tables must be protected by a mutex.
*/
static Hash lockHash = {SQLITE_HASH_BINARY, 0, 0, 0, 0, 0};

static Hash openHash = {SQLITE_HASH_BINARY, 0, 0, 0, 0, 0};


#ifdef SQLITE_ENABLE_LOCKING_STYLE
/*
** The locking styles are associated with the different file locking
** capabilities supported by different file systems.  
**
** POSIX locking style fully supports shared and exclusive byte-range locks 
................................................................................
static void releaseLockInfo(struct lockInfo *pLock){
  assert( sqlite3OsInMutex(1) );
  if (pLock == NULL)
    return;
  pLock->nRef--;
  if( pLock->nRef==0 ){
    sqlite3HashInsert(&lockHash, &pLock->key, sizeof(pLock->key), 0);
    sqlite3_free(pLock);
  }
}

/*
** Release a openCnt structure previously allocated by findLockInfo().
*/
static void releaseOpenCnt(struct openCnt *pOpen){
................................................................................
  assert( sqlite3OsInMutex(1) );
  if (pOpen == NULL)
    return;
  pOpen->nRef--;
  if( pOpen->nRef==0 ){
    sqlite3HashInsert(&openHash, &pOpen->key, sizeof(pOpen->key), 0);
    free(pOpen->aPending);
    sqlite3_free(pOpen);
  }
}

#ifdef SQLITE_ENABLE_LOCKING_STYLE
/*
** Tests a byte-range locking query to see if byte range locks are 
** supported, if not we fall back to dotlockLockingStyle.
................................................................................
#endif
  memset(&key2, 0, sizeof(key2));
  key2.dev = statbuf.st_dev;
  key2.ino = statbuf.st_ino;
  pLock = (struct lockInfo*)sqlite3HashFind(&lockHash, &key1, sizeof(key1));
  if( pLock==0 ){
    struct lockInfo *pOld;
    pLock = sqlite3_malloc( sizeof(*pLock) );
    if( pLock==0 ){
      rc = 1;
      goto exit_findlockinfo;
    }
    pLock->key = key1;
    pLock->nRef = 1;
    pLock->cnt = 0;
    pLock->locktype = 0;
    pOld = sqlite3HashInsert(&lockHash, &pLock->key, sizeof(key1), pLock);
    if( pOld!=0 ){
      assert( pOld==pLock );
      sqlite3_free(pLock);
      rc = 1;
      goto exit_findlockinfo;
    }
  }else{
    pLock->nRef++;
  }
  *ppLock = pLock;
  if( ppOpen!=0 ){
    pOpen = (struct openCnt*)sqlite3HashFind(&openHash, &key2, sizeof(key2));
    if( pOpen==0 ){
      struct openCnt *pOld;
      pOpen = sqlite3_malloc( sizeof(*pOpen) );
      if( pOpen==0 ){
        releaseLockInfo(pLock);
        rc = 1;
        goto exit_findlockinfo;
      }
      pOpen->key = key2;
      pOpen->nRef = 1;
      pOpen->nLock = 0;
      pOpen->nPending = 0;
      pOpen->aPending = 0;
      pOld = sqlite3HashInsert(&openHash, &pOpen->key, sizeof(key2), pOpen);
      if( pOld!=0 ){
        assert( pOld==pOpen );
        sqlite3_free(pOpen);
        releaseLockInfo(pLock);
        rc = 1;
        goto exit_findlockinfo;
      }
    }else{
      pOpen->nRef++;
    }
................................................................................
  releaseLockInfo(pFile->pLock);
  releaseOpenCnt(pFile->pOpen);

  sqlite3OsLeaveMutex();
  pFile->isOpen = 0;
  OSTRACE2("CLOSE   %-3d\n", pFile->h);
  OpenCounter(-1);
  sqlite3_free(id);
  return SQLITE_OK;
}


#ifdef SQLITE_ENABLE_LOCKING_STYLE
#pragma mark AFP Support

................................................................................
  unixFile *id = (unixFile*)*pId;
  
  if( !id ) return SQLITE_OK;
  afpUnixUnlock(*pId, NO_LOCK);
  /* free the AFP locking structure */
  if (id->lockingContext != NULL) {
    if (((afpLockingContext *)id->lockingContext)->filePath != NULL)
      sqlite3_free(((afpLockingContext*)id->lockingContext)->filePath);
    sqlite3_free(id->lockingContext);
  }
  
  if( id->dirfd>=0 ) close(id->dirfd);
  id->dirfd = -1;
  close(id->h);
  id->isOpen = 0;
  OSTRACE2("CLOSE   %-3d\n", id->h);
  OpenCounter(-1);
  sqlite3_free(id);
  *pId = 0;
  return SQLITE_OK;
}


#pragma mark flock() style locking

................................................................................
  sqlite3OsEnterMutex();
  
  close(id->h);  
  sqlite3OsLeaveMutex();
  id->isOpen = 0;
  OSTRACE2("CLOSE   %-3d\n", id->h);
  OpenCounter(-1);
  sqlite3_free(id);
  *pId = 0;
  return SQLITE_OK;
}

#pragma mark Old-School .lock file based locking

/*
................................................................................
  unixFile *id = (unixFile*)*pId;
  
  if( !id ) return SQLITE_OK;
  dotlockUnixUnlock(*pId, NO_LOCK);
  /* free the dotlock locking structure */
  if (id->lockingContext != NULL) {
    if (((dotlockLockingContext *)id->lockingContext)->lockPath != NULL)
      sqlite3_free( ( (dotlockLockingContext *)
        id->lockingContext)->lockPath);
    sqlite3_free(id->lockingContext);
  }
  
  if( id->dirfd>=0 ) close(id->dirfd);
  id->dirfd = -1;
  sqlite3OsEnterMutex();
  
  close(id->h);
  
  sqlite3OsLeaveMutex();
  id->isOpen = 0;
  OSTRACE2("CLOSE   %-3d\n", id->h);
  OpenCounter(-1);
  sqlite3_free(id);
  *pId = 0;
  return SQLITE_OK;
}


#pragma mark No locking

................................................................................
  
  close(id->h);
  
  sqlite3OsLeaveMutex();
  id->isOpen = 0;
  OSTRACE2("CLOSE   %-3d\n", id->h);
  OpenCounter(-1);
  sqlite3_free(id);
  *pId = 0;
  return SQLITE_OK;
}

#endif /* SQLITE_ENABLE_LOCKING_STYLE */

/*
................................................................................
** is no longer needed.
*/
char *sqlite3UnixFullPathname(const char *zRelative){
  char *zFull = 0;
  if( zRelative[0]=='/' ){
    sqlite3SetString(&zFull, zRelative, (char*)0);
  }else{
    char *zBuf = sqlite3_malloc(5000);
    if( zBuf==0 ){
      return 0;
    }
    zBuf[0] = 0;
    sqlite3SetString(&zFull, getcwd(zBuf, 5000), "/", zRelative,
                    (char*)0);
    sqliteFree(zBuf);
................................................................................
  }
  if( delFlag ){
    unlink(zFilename);
  }
  f.dirfd = -1;
  f.h = h;
  SET_THREADID(&f);
  pNew = sqlite3_malloc( sizeof(unixFile) );
  if( pNew==0 ){
    close(h);
    sqlite3OsEnterMutex();
    releaseLockInfo(f.pLock);
    releaseOpenCnt(f.pOpen);
    sqlite3OsLeaveMutex();
    *pId = 0;
................................................................................
    switch(lockingStyle) {
      case afpLockingStyle: {
        /* afp locking uses the file path so it needs to be included in
        ** the afpLockingContext */
        int nFilename;
        pNew->pMethod = &sqlite3AFPLockingUnixIoMethod;
        pNew->lockingContext = 
          sqlite3_malloc(sizeof(afpLockingContext));
        nFilename = strlen(zFilename)+1;
        ((afpLockingContext *)pNew->lockingContext)->filePath = 
          sqlite3_malloc(nFilename);
        memcpy(((afpLockingContext *)pNew->lockingContext)->filePath, 
               zFilename, nFilename);
        srandomdev();
        break;
      }
      case flockLockingStyle:
        /* flock locking doesn't need additional lockingContext information */
................................................................................
        pNew->pMethod = &sqlite3FlockLockingUnixIoMethod;
        break;
      case dotlockLockingStyle: {
        /* dotlock locking uses the file path so it needs to be included in
         ** the dotlockLockingContext */
        int nFilename;
        pNew->pMethod = &sqlite3DotlockLockingUnixIoMethod;
        pNew->lockingContext = sqlite3_malloc(
          sizeof(dotlockLockingContext));
        nFilename = strlen(zFilename) + 6;
        ((dotlockLockingContext *)pNew->lockingContext)->lockPath = 
            sqlite3_malloc( nFilename );
        sqlite3_snprintf(nFilename, 
                ((dotlockLockingContext *)pNew->lockingContext)->lockPath, 
                "%s.lock", zFilename);
        break;
      }
      case posixLockingStyle:
        /* posix locking doesn't need additional lockingContext information */
................................................................................
    close(h);
    return SQLITE_NOMEM;
  }
  OSTRACE3("OPEN    %-3d %s\n", h, zFilename);
  f.dirfd = -1;
  f.h = h;
  SET_THREADID(&f);
  pNew = sqlite3_malloc( sizeof(unixFile) );
  if( pNew==0 ){
    close(h);
    sqlite3OsEnterMutex();
    releaseLockInfo(f.pLock);
    releaseOpenCnt(f.pOpen);
    sqlite3OsLeaveMutex();
    *pId = 0;

** The pager is used to access a database disk file.  It implements
** atomic commit and rollback through the use of a journal file that
** is separate from the database file.  The pager also implements file
** locking to prevent two processes from writing the same database
** file simultaneously, or one process from reading the database while
** another is writing.
**
** @(#) $Id: pager.c,v 1.356 2007/08/15 17:08:46 danielk1977 Exp $
*/
#ifndef SQLITE_OMIT_DISKIO
#include "sqliteInt.h"
#include "os.h"
#include "pager.h"
#include <assert.h>
#include <string.h>
................................................................................
/*
** Change the size of the pager hash table to N.  N must be a power
** of two.
*/
static void pager_resize_hash_table(Pager *pPager, int N){
  PgHdr **aHash, *pPg;
  assert( N>0 && (N&(N-1))==0 );
  aHash = sqliteMalloc( sizeof(aHash[0])*N );
  if( aHash==0 ){
    /* Failure to rehash is not an error.  It is only a performance hit. */
    return;
  }
  sqliteFree(pPager->aHash);
  pPager->nHash = N;
  pPager->aHash = aHash;
  for(pPg=pPager->pAll; pPg; pPg=pPg->pNextAll){
    int h;
    if( pPg->pgno==0 ){
      assert( pPg->pNextHash==0 && pPg->pPrevHash==0 );
      continue;
................................................................................
#define pager_pagehash(X)  0
#define CHECK_PAGE(x)
#endif

/*
** When this is called the journal file for pager pPager must be open.
** The master journal file name is read from the end of the file and 
** written into memory obtained from sqliteMalloc(). *pzMaster is
** set to point at the memory and SQLITE_OK returned. The caller must
** sqliteFree() *pzMaster.
**
** If no master journal file name is present *pzMaster is set to 0 and
** SQLITE_OK returned.
*/
static int readMasterJournal(sqlite3_file *pJrnl, char **pzMaster){
  int rc;
  u32 len;
................................................................................

  rc = read32bits(pJrnl, szJ-12, &cksum);
  if( rc!=SQLITE_OK ) return rc;

  rc = sqlite3OsRead(pJrnl, aMagic, 8, szJ-8);
  if( rc!=SQLITE_OK || memcmp(aMagic, aJournalMagic, 8) ) return rc;

  *pzMaster = (char *)sqliteMalloc(len+1);
  if( !*pzMaster ){
    return SQLITE_NOMEM;
  }
  rc = sqlite3OsRead(pJrnl, *pzMaster, len, szJ-16-len);
  if( rc!=SQLITE_OK ){
    sqliteFree(*pzMaster);
    *pzMaster = 0;
    return rc;
  }

  /* See if the checksum matches the master journal name */
  for(i=0; i<len; i++){
    cksum -= (*pzMaster)[i];
................................................................................
  }
  if( cksum ){
    /* If the checksum doesn't add up, then one or more of the disk sectors
    ** containing the master journal filename is corrupted. This means
    ** definitely roll back, so just return SQLITE_OK and report a (nul)
    ** master-journal filename.
    */
    sqliteFree(*pzMaster);
    *pzMaster = 0;
  }else{
    (*pzMaster)[len] = '\0';
  }
   
  return SQLITE_OK;
}
................................................................................
static void pager_reset(Pager *pPager){
  PgHdr *pPg, *pNext;
  if( pPager->errCode ) return;
  for(pPg=pPager->pAll; pPg; pPg=pNext){
    IOTRACE(("PGFREE %p %d\n", pPager, pPg->pgno));
    PAGER_INCR(sqlite3_pager_pgfree_count);
    pNext = pPg->pNextAll;
    sqliteFree(pPg);
  }
  pPager->pStmt = 0;
  pPager->pFirst = 0;
  pPager->pFirstSynced = 0;
  pPager->pLast = 0;
  pPager->pAll = 0;
  pPager->nHash = 0;
  sqliteFree(pPager->aHash);
  pPager->nPage = 0;
  pPager->aHash = 0;
  pPager->nRef = 0;
}

/*
** This routine ends a transaction.  A transaction is ended by either
................................................................................
    }else{
      sqlite3OsClose(&pPager->jfd);
      pPager->journalOpen = 0;
      if( rc==SQLITE_OK ){
        rc = sqlite3OsDelete(pPager->zJournal);
      }
    }
    sqliteFree( pPager->aInJournal );
    pPager->aInJournal = 0;
    for(pPg=pPager->pAll; pPg; pPg=pPg->pNextAll){
      pPg->inJournal = 0;
      pPg->dirty = 0;
      pPg->needSync = 0;
      pPg->alwaysRollback = 0;
#ifdef SQLITE_CHECK_PAGES
................................................................................
  if( rc!=SQLITE_OK ) goto delmaster_out;

  if( nMasterJournal>0 ){
    char *zJournal;
    char *zMasterPtr = 0;

    /* Load the entire master journal file into space obtained from
    ** sqliteMalloc() and pointed to by zMasterJournal. 
    */
    zMasterJournal = (char *)sqliteMalloc(nMasterJournal);
    if( !zMasterJournal ){
      rc = SQLITE_NOMEM;
      goto delmaster_out;
    }
    rc = sqlite3OsRead(master, zMasterJournal, nMasterJournal, 0);
    if( rc!=SQLITE_OK ) goto delmaster_out;

................................................................................
        rc = readMasterJournal(journal, &zMasterPtr);
        sqlite3OsClose(&journal);
        if( rc!=SQLITE_OK ){
          goto delmaster_out;
        }

        c = zMasterPtr!=0 && strcmp(zMasterPtr, zMaster)==0;
        sqliteFree(zMasterPtr);
        if( c ){
          /* We have a match. Do not delete the master journal file. */
          goto delmaster_out;
        }
      }
      zJournal += (strlen(zJournal)+1);
    }
  }
  
  rc = sqlite3OsDelete(zMaster);

delmaster_out:
  if( zMasterJournal ){
    sqliteFree(zMasterJournal);
  }  
  if( master_open ){
    sqlite3OsClose(&master);
  }
  return rc;
}

................................................................................
  ** If a master journal file name is specified, but the file is not
  ** present on disk, then the journal is not hot and does not need to be
  ** played back.
  */
  rc = readMasterJournal(pPager->jfd, &zMaster);
  assert( rc!=SQLITE_DONE );
  if( rc!=SQLITE_OK || (zMaster && !sqlite3OsFileExists(zMaster)) ){
    sqliteFree(zMaster);
    zMaster = 0;
    if( rc==SQLITE_DONE ) rc = SQLITE_OK;
    goto end_playback;
  }
  pPager->journalOff = 0;

  /* This loop terminates either when the readJournalHdr() call returns
................................................................................
  if( zMaster ){
    /* If there was a master journal and this routine will return success,
    ** see if it is possible to delete the master journal.
    */
    if( rc==SQLITE_OK ){
      rc = pager_delmaster(zMaster);
    }
    sqliteFree(zMaster);
  }

  /* The Pager.sectorSize variable may have been updated while rolling
  ** back a journal created by a process with a different sector size
  ** value. Reset it to the correct value for this process.
  */
  setSectorSize(pPager);
................................................................................
  ThreadData *pTsd = sqlite3ThreadData();
  assert( pTsd );
#endif

  /* We used to test if malloc() had already failed before proceeding. 
  ** But the way this function is used in SQLite means that can never
  ** happen. Furthermore, if the malloc-failed flag is already set, 
  ** either the call to sqliteStrDup() or sqliteMalloc() below will
  ** fail shortly and SQLITE_NOMEM returned anyway.
  */
  *ppPager = 0;

  /* Open the pager file and set zFullPathname to point at malloc()ed 
  ** memory containing the complete filename (i.e. including the directory).
  */
  if( zFilename && zFilename[0] ){
#ifndef SQLITE_OMIT_MEMORYDB
    if( strcmp(zFilename,":memory:")==0 ){
      memDb = 1;
      zFullPathname = sqliteStrDup("");
    }else
#endif
    {
      zFullPathname = sqlite3OsFullPathname(zFilename);
      if( zFullPathname ){
        rc = sqlite3OsOpenReadWrite(zFullPathname, &fd, &readOnly);
        assert( rc!=SQLITE_OK || fd );
................................................................................

  /* Allocate the Pager structure. As part of the same allocation, allocate
  ** space for the full paths of the file, directory and journal 
  ** (Pager.zFilename, Pager.zDirectory and Pager.zJournal).
  */
  if( zFullPathname ){
    nameLen = strlen(zFullPathname);
    pPager = sqliteMalloc( sizeof(*pPager) + nameLen*3 + 30 );
    if( pPager && rc==SQLITE_OK ){
      pPager->pTmpSpace = (char *)sqliteMallocRaw(SQLITE_DEFAULT_PAGE_SIZE);
    }
  }


  /* If an error occured in either of the blocks above, free the memory 
  ** pointed to by zFullPathname, free the Pager structure and close the 
  ** file. Since the pager is not allocated there is no need to set 
  ** any Pager.errMask variables.
  */
  if( !pPager || !zFullPathname || !pPager->pTmpSpace || rc!=SQLITE_OK ){
    sqlite3OsClose(&fd);
    sqliteFree(zFullPathname);
    sqliteFree(pPager);
    return ((rc==SQLITE_OK)?SQLITE_NOMEM:rc);
  }

  PAGERTRACE3("OPEN %d %s\n", FILEHANDLEID(fd), zFullPathname);
  IOTRACE(("OPEN %p %s\n", pPager, zFullPathname))
  pPager->zFilename = (char*)&pPager[1];
  pPager->zDirectory = &pPager->zFilename[nameLen+1];
................................................................................
  pPager->zJournal = &pPager->zDirectory[nameLen+1];
  memcpy(pPager->zFilename, zFullPathname, nameLen+1);
  memcpy(pPager->zDirectory, zFullPathname, nameLen+1);

  for(i=nameLen; i>0 && pPager->zDirectory[i-1]!='/'; i--){}
  if( i>0 ) pPager->zDirectory[i-1] = 0;
  memcpy(pPager->zJournal, zFullPathname,nameLen);
  sqliteFree(zFullPathname);
  memcpy(&pPager->zJournal[nameLen], "-journal",sizeof("-journal"));
  pPager->fd = fd;
  /* pPager->journalOpen = 0; */
  pPager->useJournal = useJournal && !memDb;
  pPager->noReadlock = noReadlock && readOnly;
  /* pPager->stmtOpen = 0; */
  /* pPager->stmtInUse = 0; */
................................................................................
** and returned.
*/
int sqlite3PagerSetPagesize(Pager *pPager, int pageSize){
  assert( pageSize>=512 && pageSize<=SQLITE_MAX_PAGE_SIZE );
  if( !pPager->memDb && pPager->nRef==0 ){
    pager_reset(pPager);
    pPager->pageSize = pageSize;

    pPager->pTmpSpace = sqlite3ReallocOrFree(pPager->pTmpSpace, pageSize);
  }
  return pPager->pageSize;
}

/*
** Attempt to set the maximum database page count if mxPage is positive. 
** Make no changes if mxPage is zero or negative.  And never reduce the
................................................................................


#ifndef SQLITE_OMIT_MEMORYDB
/*
** Clear a PgHistory block
*/
static void clearHistory(PgHistory *pHist){
  sqliteFree(pHist->pOrig);
  sqliteFree(pHist->pStmt);
  pHist->pOrig = 0;
  pHist->pStmt = 0;
}
#else
#define clearHistory(x)
#endif

................................................................................
      ppPg = &pPg->pNextAll;
    }else{
      *ppPg = pPg->pNextAll;
      IOTRACE(("PGFREE %p %d\n", pPager, pPg->pgno));
      PAGER_INCR(sqlite3_pager_pgfree_count);
      unlinkPage(pPg);
      makeClean(pPg);
      sqliteFree(pPg);
      pPager->nPage--;
    }
  }
}

/*
** Try to obtain a lock on a file.  Invoke the busy callback if the lock
................................................................................
  enable_simulated_io_errors();
  PAGERTRACE2("CLOSE %d\n", PAGERID(pPager));
  IOTRACE(("CLOSE %p\n", pPager))
  assert( pPager->errCode || (pPager->journalOpen==0 && pPager->stmtOpen==0) );
  if( pPager->journalOpen ){
    sqlite3OsClose(&pPager->jfd);
  }
  sqliteFree(pPager->aInJournal);
  if( pPager->stmtOpen ){
    sqlite3OsClose(&pPager->stfd);
  }
  sqlite3OsClose(&pPager->fd);
  /* Temp files are automatically deleted by the OS
  ** if( pPager->tempFile ){
  **   sqlite3OsDelete(pPager->zFilename);
................................................................................
    pTsd->pPager = pPager->pNext;
  }else{
    Pager *pTmp;
    for(pTmp = pTsd->pPager; pTmp->pNext!=pPager; pTmp=pTmp->pNext){}
    pTmp->pNext = pPager->pNext;
  }
#endif
  sqliteFree(pPager->aHash);
  sqliteFree(pPager->pTmpSpace);
  sqliteFree(pPager);
  return SQLITE_OK;
}

#if !defined(NDEBUG) || defined(SQLITE_TEST)
/*
** Return the page number for the given page data.
*/
................................................................................
  *ppPg = pPg;
  return SQLITE_OK;
}

/*
** This function is called to free superfluous dynamically allocated memory
** held by the pager system. Memory in use by any SQLite pager allocated
** by the current thread may be sqliteFree()ed.
**
** nReq is the number of bytes of memory required. Once this much has
** been released, the function returns. A negative value for nReq means
** free as much memory as possible. The return value is the total number 
** of bytes of memory released.
*/
#if defined(SQLITE_ENABLE_MEMORY_MANAGEMENT) && !defined(SQLITE_OMIT_DISKIO)
................................................................................
        }else{
          for( pTmp=pPager->pAll; pTmp->pNextAll!=pPg; pTmp=pTmp->pNextAll ){}
          pTmp->pNextAll = pPg->pNextAll;
        }
        nReleased += sqliteAllocSize(pPg);
        IOTRACE(("PGFREE %p %d *\n", pPager, pPg->pgno));
        PAGER_INCR(sqlite3_pager_pgfree_count);
        sqliteFree(pPg);
      }

      if( rc!=SQLITE_OK ){
        /* An error occured whilst writing to the database file or 
        ** journal in pager_recycle(). The error is not returned to the 
        ** caller of this function. Instead, set the Pager.errCode variable.
        ** The error will be returned to the user (or users, in the case 
................................................................................
      pager_resize_hash_table(pPager,
         pPager->nHash<256 ? 256 : pPager->nHash*2);
      if( pPager->nHash==0 ){
        rc = SQLITE_NOMEM;
        goto pager_allocate_out;
      }
    }
    pPg = sqliteMallocRaw( sizeof(*pPg) + pPager->pageSize
                            + sizeof(u32) + pPager->nExtra
                            + MEMDB*sizeof(PgHistory) );
    if( pPg==0 ){
      rc = SQLITE_NOMEM;
      goto pager_allocate_out;
    }
    memset(pPg, 0, sizeof(*pPg));
................................................................................
  int rc;
  assert( !MEMDB );
  assert( pPager->state>=PAGER_RESERVED );
  assert( pPager->journalOpen==0 );
  assert( pPager->useJournal );
  assert( pPager->aInJournal==0 );
  sqlite3PagerPagecount(pPager);
  pPager->aInJournal = sqliteMalloc( pPager->dbSize/8 + 1 );
  if( pPager->aInJournal==0 ){
    rc = SQLITE_NOMEM;
    goto failed_to_open_journal;
  }
  rc = sqlite3OsOpenExclusive(pPager->zJournal, &pPager->jfd,
                                 pPager->tempFile);
  assert( rc!=SQLITE_OK || pPager->jfd );
................................................................................
    if( rc==SQLITE_OK ){
      rc = SQLITE_FULL;
    }
  }
  return rc;

failed_to_open_journal:
  sqliteFree(pPager->aInJournal);
  pPager->aInJournal = 0;
  return rc;
}

/*
** Acquire a write-lock on the database.  The lock is removed when
** the any of the following happen:
................................................................................
    ** by this connection. Instead of deleting the journal file it was 
    ** kept open and truncated to 0 bytes.
    */
    assert( pPager->nRec==0 );
    assert( pPager->origDbSize==0 );
    assert( pPager->aInJournal==0 );
    sqlite3PagerPagecount(pPager);
    pPager->aInJournal = sqliteMalloc( pPager->dbSize/8 + 1 );
    if( !pPager->aInJournal ){
      rc = SQLITE_NOMEM;
    }else{
      pPager->origDbSize = pPager->dbSize;
      rc = writeJournalHdr(pPager);
    }
  }
................................................................................
    if( !pPg->inJournal && (pPager->useJournal || MEMDB) ){
      if( (int)pPg->pgno <= pPager->origDbSize ){
        int szPg;
        if( MEMDB ){
          PgHistory *pHist = PGHDR_TO_HIST(pPg, pPager);
          PAGERTRACE3("JOURNAL %d page %d\n", PAGERID(pPager), pPg->pgno);
          assert( pHist->pOrig==0 );
          pHist->pOrig = sqliteMallocRaw( pPager->pageSize );
          if( pHist->pOrig ){
            memcpy(pHist->pOrig, PGHDR_TO_DATA(pPg), pPager->pageSize);
          }
        }else{
          u32 cksum, saved;
          char *pData2, *pEnd;
          /* We should never write to the journal file the page that
................................................................................
     && !pageInStatement(pPg) 
     && (int)pPg->pgno<=pPager->stmtSize 
    ){
      assert( pPg->inJournal || (int)pPg->pgno>pPager->origDbSize );
      if( MEMDB ){
        PgHistory *pHist = PGHDR_TO_HIST(pPg, pPager);
        assert( pHist->pStmt==0 );
        pHist->pStmt = sqliteMallocRaw( pPager->pageSize );
        if( pHist->pStmt ){
          memcpy(pHist->pStmt, PGHDR_TO_DATA(pPg), pPager->pageSize);
        }
        PAGERTRACE3("STMT-JOURNAL %d page %d\n", PAGERID(pPager), pPg->pgno);
        page_add_to_stmt_list(pPg);
      }else{
        i64 offset = pPager->stmtNRec*(4+pPager->pageSize);
................................................................................
    return SQLITE_OK;
  }
  if( !pPager->journalOpen ){
    pPager->stmtAutoopen = 1;
    return SQLITE_OK;
  }
  assert( pPager->journalOpen );
  pPager->aInStmt = sqliteMalloc( pPager->dbSize/8 + 1 );
  if( pPager->aInStmt==0 ){
    /* sqlite3OsLock(pPager->fd, SHARED_LOCK); */
    return SQLITE_NOMEM;
  }
#ifndef NDEBUG
  rc = sqlite3OsFileSize(pPager->jfd, &pPager->stmtJSize);
  if( rc ) goto stmt_begin_failed;
................................................................................
    pPager->stmtNRec = 0;
  }
  pPager->stmtInUse = 1;
  return SQLITE_OK;
 
stmt_begin_failed:
  if( pPager->aInStmt ){
    sqliteFree(pPager->aInStmt);
    pPager->aInStmt = 0;
  }
  return rc;
}

/*
** Commit a statement.
................................................................................
*/
int sqlite3PagerStmtCommit(Pager *pPager){
  if( pPager->stmtInUse ){
    PgHdr *pPg, *pNext;
    PAGERTRACE2("STMT-COMMIT %d\n", PAGERID(pPager));
    if( !MEMDB ){
      /* sqlite3OsTruncate(pPager->stfd, 0); */
      sqliteFree( pPager->aInStmt );
      pPager->aInStmt = 0;
    }else{
      for(pPg=pPager->pStmt; pPg; pPg=pNext){
        PgHistory *pHist = PGHDR_TO_HIST(pPg, pPager);
        pNext = pHist->pNextStmt;
        assert( pHist->inStmt );
        pHist->inStmt = 0;
        pHist->pPrevStmt = pHist->pNextStmt = 0;
        sqliteFree(pHist->pStmt);
        pHist->pStmt = 0;
      }
    }
    pPager->stmtNRec = 0;
    pPager->stmtInUse = 0;
    pPager->pStmt = 0;
  }
................................................................................
    if( MEMDB ){
      PgHdr *pPg;
      PgHistory *pHist;
      for(pPg=pPager->pStmt; pPg; pPg=pHist->pNextStmt){
        pHist = PGHDR_TO_HIST(pPg, pPager);
        if( pHist->pStmt ){
          memcpy(PGHDR_TO_DATA(pPg), pHist->pStmt, pPager->pageSize);
          sqliteFree(pHist->pStmt);
          pHist->pStmt = 0;
        }
      }
      pPager->dbSize = pPager->stmtSize;
      pager_truncate_cache(pPager);
      rc = SQLITE_OK;
    }else{

** The pager is used to access a database disk file.  It implements
** atomic commit and rollback through the use of a journal file that
** is separate from the database file.  The pager also implements file
** locking to prevent two processes from writing the same database
** file simultaneously, or one process from reading the database while
** another is writing.
**
** @(#) $Id: pager.c,v 1.357 2007/08/16 04:30:40 drh Exp $
*/
#ifndef SQLITE_OMIT_DISKIO
#include "sqliteInt.h"
#include "os.h"
#include "pager.h"
#include <assert.h>
#include <string.h>
................................................................................
/*
** Change the size of the pager hash table to N.  N must be a power
** of two.
*/
static void pager_resize_hash_table(Pager *pPager, int N){
  PgHdr **aHash, *pPg;
  assert( N>0 && (N&(N-1))==0 );
  aHash = sqlite3MallocZero( sizeof(aHash[0])*N );
  if( aHash==0 ){
    /* Failure to rehash is not an error.  It is only a performance hit. */
    return;
  }
  sqlite3_free(pPager->aHash);
  pPager->nHash = N;
  pPager->aHash = aHash;
  for(pPg=pPager->pAll; pPg; pPg=pPg->pNextAll){
    int h;
    if( pPg->pgno==0 ){
      assert( pPg->pNextHash==0 && pPg->pPrevHash==0 );
      continue;
................................................................................
#define pager_pagehash(X)  0
#define CHECK_PAGE(x)
#endif

/*
** When this is called the journal file for pager pPager must be open.
** The master journal file name is read from the end of the file and 
** written into memory obtained from sqlite3_malloc(). *pzMaster is
** set to point at the memory and SQLITE_OK returned. The caller must
** sqlite3_free() *pzMaster.
**
** If no master journal file name is present *pzMaster is set to 0 and
** SQLITE_OK returned.
*/
static int readMasterJournal(sqlite3_file *pJrnl, char **pzMaster){
  int rc;
  u32 len;
................................................................................

  rc = read32bits(pJrnl, szJ-12, &cksum);
  if( rc!=SQLITE_OK ) return rc;

  rc = sqlite3OsRead(pJrnl, aMagic, 8, szJ-8);
  if( rc!=SQLITE_OK || memcmp(aMagic, aJournalMagic, 8) ) return rc;

  *pzMaster = (char *)sqlite3MallocZero(len+1);
  if( !*pzMaster ){
    return SQLITE_NOMEM;
  }
  rc = sqlite3OsRead(pJrnl, *pzMaster, len, szJ-16-len);
  if( rc!=SQLITE_OK ){
    sqlite3_free(*pzMaster);
    *pzMaster = 0;
    return rc;
  }

  /* See if the checksum matches the master journal name */
  for(i=0; i<len; i++){
    cksum -= (*pzMaster)[i];
................................................................................
  }
  if( cksum ){
    /* If the checksum doesn't add up, then one or more of the disk sectors
    ** containing the master journal filename is corrupted. This means
    ** definitely roll back, so just return SQLITE_OK and report a (nul)
    ** master-journal filename.
    */
    sqlite3_free(*pzMaster);
    *pzMaster = 0;
  }else{
    (*pzMaster)[len] = '\0';
  }
   
  return SQLITE_OK;
}
................................................................................
static void pager_reset(Pager *pPager){
  PgHdr *pPg, *pNext;
  if( pPager->errCode ) return;
  for(pPg=pPager->pAll; pPg; pPg=pNext){
    IOTRACE(("PGFREE %p %d\n", pPager, pPg->pgno));
    PAGER_INCR(sqlite3_pager_pgfree_count);
    pNext = pPg->pNextAll;
    sqlite3_free(pPg);
  }
  pPager->pStmt = 0;
  pPager->pFirst = 0;
  pPager->pFirstSynced = 0;
  pPager->pLast = 0;
  pPager->pAll = 0;
  pPager->nHash = 0;
  sqlite3_free(pPager->aHash);
  pPager->nPage = 0;
  pPager->aHash = 0;
  pPager->nRef = 0;
}

/*
** This routine ends a transaction.  A transaction is ended by either
................................................................................
    }else{
      sqlite3OsClose(&pPager->jfd);
      pPager->journalOpen = 0;
      if( rc==SQLITE_OK ){
        rc = sqlite3OsDelete(pPager->zJournal);
      }
    }
    sqlite3_free( pPager->aInJournal );
    pPager->aInJournal = 0;
    for(pPg=pPager->pAll; pPg; pPg=pPg->pNextAll){
      pPg->inJournal = 0;
      pPg->dirty = 0;
      pPg->needSync = 0;
      pPg->alwaysRollback = 0;
#ifdef SQLITE_CHECK_PAGES
................................................................................
  if( rc!=SQLITE_OK ) goto delmaster_out;

  if( nMasterJournal>0 ){
    char *zJournal;
    char *zMasterPtr = 0;

    /* Load the entire master journal file into space obtained from
    ** sqlite3_malloc() and pointed to by zMasterJournal. 
    */
    zMasterJournal = (char *)sqlite3_malloc(nMasterJournal);
    if( !zMasterJournal ){
      rc = SQLITE_NOMEM;
      goto delmaster_out;
    }
    rc = sqlite3OsRead(master, zMasterJournal, nMasterJournal, 0);
    if( rc!=SQLITE_OK ) goto delmaster_out;

................................................................................
        rc = readMasterJournal(journal, &zMasterPtr);
        sqlite3OsClose(&journal);
        if( rc!=SQLITE_OK ){
          goto delmaster_out;
        }

        c = zMasterPtr!=0 && strcmp(zMasterPtr, zMaster)==0;
        sqlite3_free(zMasterPtr);
        if( c ){
          /* We have a match. Do not delete the master journal file. */
          goto delmaster_out;
        }
      }
      zJournal += (strlen(zJournal)+1);
    }
  }
  
  rc = sqlite3OsDelete(zMaster);

delmaster_out:
  if( zMasterJournal ){
    sqlite3_free(zMasterJournal);
  }  
  if( master_open ){
    sqlite3OsClose(&master);
  }
  return rc;
}

................................................................................
  ** If a master journal file name is specified, but the file is not
  ** present on disk, then the journal is not hot and does not need to be
  ** played back.
  */
  rc = readMasterJournal(pPager->jfd, &zMaster);
  assert( rc!=SQLITE_DONE );
  if( rc!=SQLITE_OK || (zMaster && !sqlite3OsFileExists(zMaster)) ){
    sqlite3_free(zMaster);
    zMaster = 0;
    if( rc==SQLITE_DONE ) rc = SQLITE_OK;
    goto end_playback;
  }
  pPager->journalOff = 0;

  /* This loop terminates either when the readJournalHdr() call returns
................................................................................
  if( zMaster ){
    /* If there was a master journal and this routine will return success,
    ** see if it is possible to delete the master journal.
    */
    if( rc==SQLITE_OK ){
      rc = pager_delmaster(zMaster);
    }
    sqlite3_free(zMaster);
  }

  /* The Pager.sectorSize variable may have been updated while rolling
  ** back a journal created by a process with a different sector size
  ** value. Reset it to the correct value for this process.
  */
  setSectorSize(pPager);
................................................................................
  ThreadData *pTsd = sqlite3ThreadData();
  assert( pTsd );
#endif

  /* We used to test if malloc() had already failed before proceeding. 
  ** But the way this function is used in SQLite means that can never
  ** happen. Furthermore, if the malloc-failed flag is already set, 
  ** either the call to sqlite3StrDup() or sqlite3_malloc() below will
  ** fail shortly and SQLITE_NOMEM returned anyway.
  */
  *ppPager = 0;

  /* Open the pager file and set zFullPathname to point at malloc()ed 
  ** memory containing the complete filename (i.e. including the directory).
  */
  if( zFilename && zFilename[0] ){
#ifndef SQLITE_OMIT_MEMORYDB
    if( strcmp(zFilename,":memory:")==0 ){
      memDb = 1;
      zFullPathname = sqlite3StrDup("");
    }else
#endif
    {
      zFullPathname = sqlite3OsFullPathname(zFilename);
      if( zFullPathname ){
        rc = sqlite3OsOpenReadWrite(zFullPathname, &fd, &readOnly);
        assert( rc!=SQLITE_OK || fd );
................................................................................

  /* Allocate the Pager structure. As part of the same allocation, allocate
  ** space for the full paths of the file, directory and journal 
  ** (Pager.zFilename, Pager.zDirectory and Pager.zJournal).
  */
  if( zFullPathname ){
    nameLen = strlen(zFullPathname);
    pPager = sqlite3MallocZero( sizeof(*pPager) + nameLen*3 + 30 );
    if( pPager && rc==SQLITE_OK ){
      pPager->pTmpSpace = (char *)sqlite3_malloc(SQLITE_DEFAULT_PAGE_SIZE);
    }
  }


  /* If an error occured in either of the blocks above, free the memory 
  ** pointed to by zFullPathname, free the Pager structure and close the 
  ** file. Since the pager is not allocated there is no need to set 
  ** any Pager.errMask variables.
  */
  if( !pPager || !zFullPathname || !pPager->pTmpSpace || rc!=SQLITE_OK ){
    sqlite3OsClose(&fd);
    sqlite3_free(zFullPathname);
    sqlite3_free(pPager);
    return ((rc==SQLITE_OK)?SQLITE_NOMEM:rc);
  }

  PAGERTRACE3("OPEN %d %s\n", FILEHANDLEID(fd), zFullPathname);
  IOTRACE(("OPEN %p %s\n", pPager, zFullPathname))
  pPager->zFilename = (char*)&pPager[1];
  pPager->zDirectory = &pPager->zFilename[nameLen+1];
................................................................................
  pPager->zJournal = &pPager->zDirectory[nameLen+1];
  memcpy(pPager->zFilename, zFullPathname, nameLen+1);
  memcpy(pPager->zDirectory, zFullPathname, nameLen+1);

  for(i=nameLen; i>0 && pPager->zDirectory[i-1]!='/'; i--){}
  if( i>0 ) pPager->zDirectory[i-1] = 0;
  memcpy(pPager->zJournal, zFullPathname,nameLen);
  sqlite3_free(zFullPathname);
  memcpy(&pPager->zJournal[nameLen], "-journal",sizeof("-journal"));
  pPager->fd = fd;
  /* pPager->journalOpen = 0; */
  pPager->useJournal = useJournal && !memDb;
  pPager->noReadlock = noReadlock && readOnly;
  /* pPager->stmtOpen = 0; */
  /* pPager->stmtInUse = 0; */
................................................................................
** and returned.
*/
int sqlite3PagerSetPagesize(Pager *pPager, int pageSize){
  assert( pageSize>=512 && pageSize<=SQLITE_MAX_PAGE_SIZE );
  if( !pPager->memDb && pPager->nRef==0 ){
    pager_reset(pPager);
    pPager->pageSize = pageSize;
    sqlite3_free(pPager->pTmpSpace);
    pPager->pTmpSpace = sqlite3_malloc(pageSize);
  }
  return pPager->pageSize;
}

/*
** Attempt to set the maximum database page count if mxPage is positive. 
** Make no changes if mxPage is zero or negative.  And never reduce the
................................................................................


#ifndef SQLITE_OMIT_MEMORYDB
/*
** Clear a PgHistory block
*/
static void clearHistory(PgHistory *pHist){
  sqlite3_free(pHist->pOrig);
  sqlite3_free(pHist->pStmt);
  pHist->pOrig = 0;
  pHist->pStmt = 0;
}
#else
#define clearHistory(x)
#endif

................................................................................
      ppPg = &pPg->pNextAll;
    }else{
      *ppPg = pPg->pNextAll;
      IOTRACE(("PGFREE %p %d\n", pPager, pPg->pgno));
      PAGER_INCR(sqlite3_pager_pgfree_count);
      unlinkPage(pPg);
      makeClean(pPg);
      sqlite3_free(pPg);
      pPager->nPage--;
    }
  }
}

/*
** Try to obtain a lock on a file.  Invoke the busy callback if the lock
................................................................................
  enable_simulated_io_errors();
  PAGERTRACE2("CLOSE %d\n", PAGERID(pPager));
  IOTRACE(("CLOSE %p\n", pPager))
  assert( pPager->errCode || (pPager->journalOpen==0 && pPager->stmtOpen==0) );
  if( pPager->journalOpen ){
    sqlite3OsClose(&pPager->jfd);
  }
  sqlite3_free(pPager->aInJournal);
  if( pPager->stmtOpen ){
    sqlite3OsClose(&pPager->stfd);
  }
  sqlite3OsClose(&pPager->fd);
  /* Temp files are automatically deleted by the OS
  ** if( pPager->tempFile ){
  **   sqlite3OsDelete(pPager->zFilename);
................................................................................
    pTsd->pPager = pPager->pNext;
  }else{
    Pager *pTmp;
    for(pTmp = pTsd->pPager; pTmp->pNext!=pPager; pTmp=pTmp->pNext){}
    pTmp->pNext = pPager->pNext;
  }
#endif
  sqlite3_free(pPager->aHash);
  sqlite3_free(pPager->pTmpSpace);
  sqlite3_free(pPager);
  return SQLITE_OK;
}

#if !defined(NDEBUG) || defined(SQLITE_TEST)
/*
** Return the page number for the given page data.
*/
................................................................................
  *ppPg = pPg;
  return SQLITE_OK;
}

/*
** This function is called to free superfluous dynamically allocated memory
** held by the pager system. Memory in use by any SQLite pager allocated
** by the current thread may be sqlite3_free()ed.
**
** nReq is the number of bytes of memory required. Once this much has
** been released, the function returns. A negative value for nReq means
** free as much memory as possible. The return value is the total number 
** of bytes of memory released.
*/
#if defined(SQLITE_ENABLE_MEMORY_MANAGEMENT) && !defined(SQLITE_OMIT_DISKIO)
................................................................................
        }else{
          for( pTmp=pPager->pAll; pTmp->pNextAll!=pPg; pTmp=pTmp->pNextAll ){}
          pTmp->pNextAll = pPg->pNextAll;
        }
        nReleased += sqliteAllocSize(pPg);
        IOTRACE(("PGFREE %p %d *\n", pPager, pPg->pgno));
        PAGER_INCR(sqlite3_pager_pgfree_count);
        sqlite3_free(pPg);
      }

      if( rc!=SQLITE_OK ){
        /* An error occured whilst writing to the database file or 
        ** journal in pager_recycle(). The error is not returned to the 
        ** caller of this function. Instead, set the Pager.errCode variable.
        ** The error will be returned to the user (or users, in the case 
................................................................................
      pager_resize_hash_table(pPager,
         pPager->nHash<256 ? 256 : pPager->nHash*2);
      if( pPager->nHash==0 ){
        rc = SQLITE_NOMEM;
        goto pager_allocate_out;
      }
    }
    pPg = sqlite3_malloc( sizeof(*pPg) + pPager->pageSize
                            + sizeof(u32) + pPager->nExtra
                            + MEMDB*sizeof(PgHistory) );
    if( pPg==0 ){
      rc = SQLITE_NOMEM;
      goto pager_allocate_out;
    }
    memset(pPg, 0, sizeof(*pPg));
................................................................................
  int rc;
  assert( !MEMDB );
  assert( pPager->state>=PAGER_RESERVED );
  assert( pPager->journalOpen==0 );
  assert( pPager->useJournal );
  assert( pPager->aInJournal==0 );
  sqlite3PagerPagecount(pPager);
  pPager->aInJournal = sqlite3MallocZero( pPager->dbSize/8 + 1 );
  if( pPager->aInJournal==0 ){
    rc = SQLITE_NOMEM;
    goto failed_to_open_journal;
  }
  rc = sqlite3OsOpenExclusive(pPager->zJournal, &pPager->jfd,
                                 pPager->tempFile);
  assert( rc!=SQLITE_OK || pPager->jfd );
................................................................................
    if( rc==SQLITE_OK ){
      rc = SQLITE_FULL;
    }
  }
  return rc;

failed_to_open_journal:
  sqlite3_free(pPager->aInJournal);
  pPager->aInJournal = 0;
  return rc;
}

/*
** Acquire a write-lock on the database.  The lock is removed when
** the any of the following happen:
................................................................................
    ** by this connection. Instead of deleting the journal file it was 
    ** kept open and truncated to 0 bytes.
    */
    assert( pPager->nRec==0 );
    assert( pPager->origDbSize==0 );
    assert( pPager->aInJournal==0 );
    sqlite3PagerPagecount(pPager);
    pPager->aInJournal = sqlite3MallocZero( pPager->dbSize/8 + 1 );
    if( !pPager->aInJournal ){
      rc = SQLITE_NOMEM;
    }else{
      pPager->origDbSize = pPager->dbSize;
      rc = writeJournalHdr(pPager);
    }
  }
................................................................................
    if( !pPg->inJournal && (pPager->useJournal || MEMDB) ){
      if( (int)pPg->pgno <= pPager->origDbSize ){
        int szPg;
        if( MEMDB ){
          PgHistory *pHist = PGHDR_TO_HIST(pPg, pPager);
          PAGERTRACE3("JOURNAL %d page %d\n", PAGERID(pPager), pPg->pgno);
          assert( pHist->pOrig==0 );
          pHist->pOrig = sqlite3_malloc( pPager->pageSize );
          if( pHist->pOrig ){
            memcpy(pHist->pOrig, PGHDR_TO_DATA(pPg), pPager->pageSize);
          }
        }else{
          u32 cksum, saved;
          char *pData2, *pEnd;
          /* We should never write to the journal file the page that
................................................................................
     && !pageInStatement(pPg) 
     && (int)pPg->pgno<=pPager->stmtSize 
    ){
      assert( pPg->inJournal || (int)pPg->pgno>pPager->origDbSize );
      if( MEMDB ){
        PgHistory *pHist = PGHDR_TO_HIST(pPg, pPager);
        assert( pHist->pStmt==0 );
        pHist->pStmt = sqlite3_malloc( pPager->pageSize );
        if( pHist->pStmt ){
          memcpy(pHist->pStmt, PGHDR_TO_DATA(pPg), pPager->pageSize);
        }
        PAGERTRACE3("STMT-JOURNAL %d page %d\n", PAGERID(pPager), pPg->pgno);
        page_add_to_stmt_list(pPg);
      }else{
        i64 offset = pPager->stmtNRec*(4+pPager->pageSize);
................................................................................
    return SQLITE_OK;
  }
  if( !pPager->journalOpen ){
    pPager->stmtAutoopen = 1;
    return SQLITE_OK;
  }
  assert( pPager->journalOpen );
  pPager->aInStmt = sqlite3MallocZero( pPager->dbSize/8 + 1 );
  if( pPager->aInStmt==0 ){
    /* sqlite3OsLock(pPager->fd, SHARED_LOCK); */
    return SQLITE_NOMEM;
  }
#ifndef NDEBUG
  rc = sqlite3OsFileSize(pPager->jfd, &pPager->stmtJSize);
  if( rc ) goto stmt_begin_failed;
................................................................................
    pPager->stmtNRec = 0;
  }
  pPager->stmtInUse = 1;
  return SQLITE_OK;
 
stmt_begin_failed:
  if( pPager->aInStmt ){
    sqlite3_free(pPager->aInStmt);
    pPager->aInStmt = 0;
  }
  return rc;
}

/*
** Commit a statement.
................................................................................
*/
int sqlite3PagerStmtCommit(Pager *pPager){
  if( pPager->stmtInUse ){
    PgHdr *pPg, *pNext;
    PAGERTRACE2("STMT-COMMIT %d\n", PAGERID(pPager));
    if( !MEMDB ){
      /* sqlite3OsTruncate(pPager->stfd, 0); */
      sqlite3_free( pPager->aInStmt );
      pPager->aInStmt = 0;
    }else{
      for(pPg=pPager->pStmt; pPg; pPg=pNext){
        PgHistory *pHist = PGHDR_TO_HIST(pPg, pPager);
        pNext = pHist->pNextStmt;
        assert( pHist->inStmt );
        pHist->inStmt = 0;
        pHist->pPrevStmt = pHist->pNextStmt = 0;
        sqlite3_free(pHist->pStmt);
        pHist->pStmt = 0;
      }
    }
    pPager->stmtNRec = 0;
    pPager->stmtInUse = 0;
    pPager->pStmt = 0;
  }
................................................................................
    if( MEMDB ){
      PgHdr *pPg;
      PgHistory *pHist;
      for(pPg=pPager->pStmt; pPg; pPg=pHist->pNextStmt){
        pHist = PGHDR_TO_HIST(pPg, pPager);
        if( pHist->pStmt ){
          memcpy(PGHDR_TO_DATA(pPg), pHist->pStmt, pPager->pageSize);
          sqlite3_free(pHist->pStmt);
          pHist->pStmt = 0;
        }
      }
      pPager->dbSize = pPager->stmtSize;
      pager_truncate_cache(pPager);
      rc = SQLITE_OK;
    }else{

**
*************************************************************************
** This file contains SQLite's grammar for SQL.  Process this file
** using the lemon parser generator to generate C code that runs
** the parser.  Lemon will also generate a header file containing
** numeric codes for all of the tokens.
**
** @(#) $Id: parse.y,v 1.231 2007/06/20 12:18:31 drh Exp $
*/

// All token codes are small integers with #defines that begin with "TK_"
%token_prefix TK_

// The type of the data attached to each token is Token.  This is also the
// default type for non-terminals.
................................................................................
carglist ::= .
carg ::= CONSTRAINT nm ccons.
carg ::= ccons.
ccons ::= DEFAULT term(X).            {sqlite3AddDefaultValue(pParse,X);}
ccons ::= DEFAULT LP expr(X) RP.      {sqlite3AddDefaultValue(pParse,X);}
ccons ::= DEFAULT PLUS term(X).       {sqlite3AddDefaultValue(pParse,X);}
ccons ::= DEFAULT MINUS term(X).      {
  Expr *p = sqlite3Expr(TK_UMINUS, X, 0, 0);
  sqlite3AddDefaultValue(pParse,p);
}
ccons ::= DEFAULT id(X).              {
  Expr *p = sqlite3Expr(TK_STRING, 0, 0, &X);
  sqlite3AddDefaultValue(pParse,p);
}

// In addition to the type name, we also care about the primary key and
// UNIQUE constraints.
//
ccons ::= NULL onconf.
................................................................................
%type multiselect_op {int}
multiselect_op(A) ::= UNION(OP).             {A = @OP;}
multiselect_op(A) ::= UNION ALL.             {A = TK_ALL;}
multiselect_op(A) ::= EXCEPT|INTERSECT(OP).  {A = @OP;}
%endif SQLITE_OMIT_COMPOUND_SELECT
oneselect(A) ::= SELECT distinct(D) selcollist(W) from(X) where_opt(Y)
                 groupby_opt(P) having_opt(Q) orderby_opt(Z) limit_opt(L). {
  A = sqlite3SelectNew(W,X,Y,P,Q,Z,D,L.pLimit,L.pOffset);
}

// The "distinct" nonterminal is true (1) if the DISTINCT keyword is
// present and false (0) if it is not.
//
%type distinct {int}
distinct(A) ::= DISTINCT.   {A = 1;}
................................................................................
%type selcollist {ExprList*}
%destructor selcollist {sqlite3ExprListDelete($$);}
%type sclp {ExprList*}
%destructor sclp {sqlite3ExprListDelete($$);}
sclp(A) ::= selcollist(X) COMMA.             {A = X;}
sclp(A) ::= .                                {A = 0;}
selcollist(A) ::= sclp(P) expr(X) as(Y).     {
   A = sqlite3ExprListAppend(P,X,Y.n?&Y:0);
}
selcollist(A) ::= sclp(P) STAR. {

  A = sqlite3ExprListAppend(P, sqlite3Expr(TK_ALL, 0, 0, 0), 0);
}
selcollist(A) ::= sclp(P) nm(X) DOT STAR. {
  Expr *pRight = sqlite3Expr(TK_ALL, 0, 0, 0);
  Expr *pLeft = sqlite3Expr(TK_ID, 0, 0, &X);

  A = sqlite3ExprListAppend(P, sqlite3Expr(TK_DOT, pLeft, pRight, 0), 0);
}

// An option "AS <id>" phrase that can follow one of the expressions that
// define the result set, or one of the tables in the FROM clause.
//
%type as {Token}
as(X) ::= AS nm(Y).    {X = Y;}
................................................................................
%type stl_prefix {SrcList*}
%destructor stl_prefix {sqlite3SrcListDelete($$);}
%type from {SrcList*}
%destructor from {sqlite3SrcListDelete($$);}

// A complete FROM clause.
//
from(A) ::= .                                 {A = sqliteMalloc(sizeof(*A));}
from(A) ::= FROM seltablist(X).               {
  A = X;
  sqlite3SrcListShiftJoinType(A);
}

// "seltablist" is a "Select Table List" - the content of the FROM clause
// in a SELECT statement.  "stl_prefix" is a prefix of this list.
//
stl_prefix(A) ::= seltablist(X) joinop(Y).    {
   A = X;
   if( A && A->nSrc>0 ) A->a[A->nSrc-1].jointype = Y;
}
stl_prefix(A) ::= .                           {A = 0;}
seltablist(A) ::= stl_prefix(X) nm(Y) dbnm(D) as(Z) on_opt(N) using_opt(U). {
  A = sqlite3SrcListAppendFromTerm(X,&Y,&D,&Z,0,N,U);
}
%ifndef SQLITE_OMIT_SUBQUERY
  seltablist(A) ::= stl_prefix(X) LP seltablist_paren(S) RP
                    as(Z) on_opt(N) using_opt(U). {
    A = sqlite3SrcListAppendFromTerm(X,0,0,&Z,S,N,U);
  }
  
  // A seltablist_paren nonterminal represents anything in a FROM that
  // is contained inside parentheses.  This can be either a subquery or
  // a grouping of table and subqueries.
  //
  %type seltablist_paren {Select*}
  %destructor seltablist_paren {sqlite3SelectDelete($$);}
  seltablist_paren(A) ::= select(S).      {A = S;}
  seltablist_paren(A) ::= seltablist(F).  {
     sqlite3SrcListShiftJoinType(F);
     A = sqlite3SelectNew(0,F,0,0,0,0,0,0,0);
  }
%endif  SQLITE_OMIT_SUBQUERY

%type dbnm {Token}
dbnm(A) ::= .          {A.z=0; A.n=0;}
dbnm(A) ::= DOT nm(X). {A = X;}

%type fullname {SrcList*}
%destructor fullname {sqlite3SrcListDelete($$);}
fullname(A) ::= nm(X) dbnm(Y).  {A = sqlite3SrcListAppend(0,&X,&Y);}

%type joinop {int}
%type joinop2 {int}
joinop(X) ::= COMMA|JOIN.              { X = JT_INNER; }
joinop(X) ::= JOIN_KW(A) JOIN.         { X = sqlite3JoinType(pParse,&A,0,0); }
joinop(X) ::= JOIN_KW(A) nm(B) JOIN.   { X = sqlite3JoinType(pParse,&A,&B,0); }
joinop(X) ::= JOIN_KW(A) nm(B) nm(C) JOIN.
................................................................................
%destructor sortlist {sqlite3ExprListDelete($$);}
%type sortitem {Expr*}
%destructor sortitem {sqlite3ExprDelete($$);}

orderby_opt(A) ::= .                          {A = 0;}
orderby_opt(A) ::= ORDER BY sortlist(X).      {A = X;}
sortlist(A) ::= sortlist(X) COMMA sortitem(Y) sortorder(Z). {
  A = sqlite3ExprListAppend(X,Y,0);
  if( A ) A->a[A->nExpr-1].sortOrder = Z;
}
sortlist(A) ::= sortitem(Y) sortorder(Z). {
  A = sqlite3ExprListAppend(0,Y,0);
  if( A && A->a ) A->a[0].sortOrder = Z;
}
sortitem(A) ::= expr(X).   {A = X;}

%type sortorder {int}

sortorder(A) ::= ASC.           {A = SQLITE_SO_ASC;}
................................................................................
  sqlite3Update(pParse,X,Y,Z,R);
}

%type setlist {ExprList*}
%destructor setlist {sqlite3ExprListDelete($$);}

setlist(A) ::= setlist(Z) COMMA nm(X) EQ expr(Y).
    {A = sqlite3ExprListAppend(Z,Y,&X);}
setlist(A) ::= nm(X) EQ expr(Y).   {A = sqlite3ExprListAppend(0,Y,&X);}


////////////////////////// The INSERT command /////////////////////////////////
//
cmd ::= insert_cmd(R) INTO fullname(X) inscollist_opt(F) 
        VALUES LP itemlist(Y) RP.
            {sqlite3Insert(pParse, X, Y, 0, F, R);}
cmd ::= insert_cmd(R) INTO fullname(X) inscollist_opt(F) select(S).
................................................................................
insert_cmd(A) ::= INSERT orconf(R).   {A = R;}
insert_cmd(A) ::= REPLACE.            {A = OE_Replace;}


%type itemlist {ExprList*}
%destructor itemlist {sqlite3ExprListDelete($$);}

itemlist(A) ::= itemlist(X) COMMA expr(Y).  {A = sqlite3ExprListAppend(X,Y,0);}

itemlist(A) ::= expr(X).                    {A = sqlite3ExprListAppend(0,X,0);}


%type inscollist_opt {IdList*}
%destructor inscollist_opt {sqlite3IdListDelete($$);}
%type inscollist {IdList*}
%destructor inscollist {sqlite3IdListDelete($$);}

inscollist_opt(A) ::= .                       {A = 0;}
inscollist_opt(A) ::= LP inscollist(X) RP.    {A = X;}
inscollist(A) ::= inscollist(X) COMMA nm(Y).  {A = sqlite3IdListAppend(X,&Y);}

inscollist(A) ::= nm(Y).                      {A = sqlite3IdListAppend(0,&Y);}


/////////////////////////// Expression Processing /////////////////////////////
//

%type expr {Expr*}
%destructor expr {sqlite3ExprDelete($$);}
%type term {Expr*}
%destructor term {sqlite3ExprDelete($$);}

expr(A) ::= term(X).             {A = X;}
expr(A) ::= LP(B) expr(X) RP(E). {A = X; sqlite3ExprSpan(A,&B,&E); }
term(A) ::= NULL(X).             {A = sqlite3Expr(@X, 0, 0, &X);}
expr(A) ::= ID(X).               {A = sqlite3Expr(TK_ID, 0, 0, &X);}
expr(A) ::= JOIN_KW(X).          {A = sqlite3Expr(TK_ID, 0, 0, &X);}
expr(A) ::= nm(X) DOT nm(Y). {
  Expr *temp1 = sqlite3Expr(TK_ID, 0, 0, &X);
  Expr *temp2 = sqlite3Expr(TK_ID, 0, 0, &Y);
  A = sqlite3Expr(TK_DOT, temp1, temp2, 0);
}
expr(A) ::= nm(X) DOT nm(Y) DOT nm(Z). {
  Expr *temp1 = sqlite3Expr(TK_ID, 0, 0, &X);
  Expr *temp2 = sqlite3Expr(TK_ID, 0, 0, &Y);
  Expr *temp3 = sqlite3Expr(TK_ID, 0, 0, &Z);
  Expr *temp4 = sqlite3Expr(TK_DOT, temp2, temp3, 0);
  A = sqlite3Expr(TK_DOT, temp1, temp4, 0);
}
term(A) ::= INTEGER|FLOAT|BLOB(X).      {A = sqlite3Expr(@X, 0, 0, &X);}
term(A) ::= STRING(X).       {A = sqlite3Expr(@X, 0, 0, &X);}
expr(A) ::= REGISTER(X).     {A = sqlite3RegisterExpr(pParse, &X);}
expr(A) ::= VARIABLE(X).     {
  Token *pToken = &X;
  Expr *pExpr = A = sqlite3Expr(TK_VARIABLE, 0, 0, pToken);
  sqlite3ExprAssignVarNumber(pParse, pExpr);
}
expr(A) ::= expr(E) COLLATE id(C). {
  A = sqlite3ExprSetColl(pParse, E, &C);
}
%ifndef SQLITE_OMIT_CAST
expr(A) ::= CAST(X) LP expr(E) AS typetoken(T) RP(Y). {
  A = sqlite3Expr(TK_CAST, E, 0, &T);
  sqlite3ExprSpan(A,&X,&Y);
}
%endif  SQLITE_OMIT_CAST
expr(A) ::= ID(X) LP distinct(D) exprlist(Y) RP(E). {
  if( Y && Y->nExpr>SQLITE_MAX_FUNCTION_ARG ){
    sqlite3ErrorMsg(pParse, "too many arguments on function %T", &X);
  }
  A = sqlite3ExprFunction(Y, &X);
  sqlite3ExprSpan(A,&X,&E);
  if( D && A ){
    A->flags |= EP_Distinct;
  }
}
expr(A) ::= ID(X) LP STAR RP(E). {
  A = sqlite3ExprFunction(0, &X);
  sqlite3ExprSpan(A,&X,&E);
}
term(A) ::= CTIME_KW(OP). {
  /* The CURRENT_TIME, CURRENT_DATE, and CURRENT_TIMESTAMP values are
  ** treated as functions that return constants */
  A = sqlite3ExprFunction(0,&OP);
  if( A ){
    A->op = TK_CONST_FUNC;  
    A->span = OP;
  }
}
expr(A) ::= expr(X) AND(OP) expr(Y).            {A = sqlite3Expr(@OP, X, Y, 0);}
expr(A) ::= expr(X) OR(OP) expr(Y).             {A = sqlite3Expr(@OP, X, Y, 0);}
expr(A) ::= expr(X) LT|GT|GE|LE(OP) expr(Y).    {A = sqlite3Expr(@OP, X, Y, 0);}

expr(A) ::= expr(X) EQ|NE(OP) expr(Y).          {A = sqlite3Expr(@OP, X, Y, 0);}
expr(A) ::= expr(X) BITAND|BITOR|LSHIFT|RSHIFT(OP) expr(Y).
                                                {A = sqlite3Expr(@OP, X, Y, 0);}

expr(A) ::= expr(X) PLUS|MINUS(OP) expr(Y).     {A = sqlite3Expr(@OP, X, Y, 0);}
expr(A) ::= expr(X) STAR|SLASH|REM(OP) expr(Y). {A = sqlite3Expr(@OP, X, Y, 0);}

expr(A) ::= expr(X) CONCAT(OP) expr(Y).         {A = sqlite3Expr(@OP, X, Y, 0);}
%type likeop {struct LikeOp}
likeop(A) ::= LIKE_KW(X).     {A.eOperator = X; A.not = 0;}
likeop(A) ::= NOT LIKE_KW(X). {A.eOperator = X; A.not = 1;}
likeop(A) ::= MATCH(X).       {A.eOperator = X; A.not = 0;}
likeop(A) ::= NOT MATCH(X).   {A.eOperator = X; A.not = 1;}
%type escape {Expr*}
%destructor escape {sqlite3ExprDelete($$);}
escape(X) ::= ESCAPE expr(A). [ESCAPE] {X = A;}
escape(X) ::= .               [ESCAPE] {X = 0;}
expr(A) ::= expr(X) likeop(OP) expr(Y) escape(E).  [LIKE_KW]  {
  ExprList *pList;
  pList = sqlite3ExprListAppend(0, Y, 0);
  pList = sqlite3ExprListAppend(pList, X, 0);
  if( E ){
    pList = sqlite3ExprListAppend(pList, E, 0);
  }
  A = sqlite3ExprFunction(pList, &OP.eOperator);
  if( OP.not ) A = sqlite3Expr(TK_NOT, A, 0, 0);
  sqlite3ExprSpan(A, &X->span, &Y->span);
  if( A ) A->flags |= EP_InfixFunc;
}

expr(A) ::= expr(X) ISNULL|NOTNULL(E). {
  A = sqlite3Expr(@E, X, 0, 0);
  sqlite3ExprSpan(A,&X->span,&E);
}
expr(A) ::= expr(X) IS NULL(E). {
  A = sqlite3Expr(TK_ISNULL, X, 0, 0);
  sqlite3ExprSpan(A,&X->span,&E);
}
expr(A) ::= expr(X) NOT NULL(E). {
  A = sqlite3Expr(TK_NOTNULL, X, 0, 0);
  sqlite3ExprSpan(A,&X->span,&E);
}
expr(A) ::= expr(X) IS NOT NULL(E). {
  A = sqlite3Expr(TK_NOTNULL, X, 0, 0);
  sqlite3ExprSpan(A,&X->span,&E);
}
expr(A) ::= NOT|BITNOT(B) expr(X). {
  A = sqlite3Expr(@B, X, 0, 0);
  sqlite3ExprSpan(A,&B,&X->span);
}
expr(A) ::= MINUS(B) expr(X). [UMINUS] {
  A = sqlite3Expr(TK_UMINUS, X, 0, 0);
  sqlite3ExprSpan(A,&B,&X->span);
}
expr(A) ::= PLUS(B) expr(X). [UPLUS] {
  A = sqlite3Expr(TK_UPLUS, X, 0, 0);
  sqlite3ExprSpan(A,&B,&X->span);
}
%type between_op {int}
between_op(A) ::= BETWEEN.     {A = 0;}
between_op(A) ::= NOT BETWEEN. {A = 1;}
expr(A) ::= expr(W) between_op(N) expr(X) AND expr(Y). [BETWEEN] {
  ExprList *pList = sqlite3ExprListAppend(0, X, 0);
  pList = sqlite3ExprListAppend(pList, Y, 0);
  A = sqlite3Expr(TK_BETWEEN, W, 0, 0);
  if( A ){
    A->pList = pList;
  }else{
    sqlite3ExprListDelete(pList);
  } 
  if( N ) A = sqlite3Expr(TK_NOT, A, 0, 0);
  sqlite3ExprSpan(A,&W->span,&Y->span);
}
%ifndef SQLITE_OMIT_SUBQUERY
  %type in_op {int}
  in_op(A) ::= IN.      {A = 0;}
  in_op(A) ::= NOT IN.  {A = 1;}
  expr(A) ::= expr(X) in_op(N) LP exprlist(Y) RP(E). [IN] {
    A = sqlite3Expr(TK_IN, X, 0, 0);
    if( A ){
      A->pList = Y;
      sqlite3ExprSetHeight(A);
    }else{
      sqlite3ExprListDelete(Y);
    }
    if( N ) A = sqlite3Expr(TK_NOT, A, 0, 0);
    sqlite3ExprSpan(A,&X->span,&E);
  }
  expr(A) ::= LP(B) select(X) RP(E). {
    A = sqlite3Expr(TK_SELECT, 0, 0, 0);
    if( A ){
      A->pSelect = X;
      sqlite3ExprSetHeight(A);
    }else{
      sqlite3SelectDelete(X);
    }
    sqlite3ExprSpan(A,&B,&E);
  }
  expr(A) ::= expr(X) in_op(N) LP select(Y) RP(E).  [IN] {
    A = sqlite3Expr(TK_IN, X, 0, 0);
    if( A ){
      A->pSelect = Y;
      sqlite3ExprSetHeight(A);
    }else{
      sqlite3SelectDelete(Y);
    }
    if( N ) A = sqlite3Expr(TK_NOT, A, 0, 0);
    sqlite3ExprSpan(A,&X->span,&E);
  }
  expr(A) ::= expr(X) in_op(N) nm(Y) dbnm(Z). [IN] {
    SrcList *pSrc = sqlite3SrcListAppend(0,&Y,&Z);
    A = sqlite3Expr(TK_IN, X, 0, 0);
    if( A ){
      A->pSelect = sqlite3SelectNew(0,pSrc,0,0,0,0,0,0,0);
      sqlite3ExprSetHeight(A);
    }else{
      sqlite3SrcListDelete(pSrc);
    }
    if( N ) A = sqlite3Expr(TK_NOT, A, 0, 0);
    sqlite3ExprSpan(A,&X->span,Z.z?&Z:&Y);
  }
  expr(A) ::= EXISTS(B) LP select(Y) RP(E). {
    Expr *p = A = sqlite3Expr(TK_EXISTS, 0, 0, 0);
    if( p ){
      p->pSelect = Y;
      sqlite3ExprSpan(p,&B,&E);
      sqlite3ExprSetHeight(A);
    }else{
      sqlite3SelectDelete(Y);
    }
  }
%endif SQLITE_OMIT_SUBQUERY

/* CASE expressions */
expr(A) ::= CASE(C) case_operand(X) case_exprlist(Y) case_else(Z) END(E). {
  A = sqlite3Expr(TK_CASE, X, Z, 0);
  if( A ){
    A->pList = Y;
    sqlite3ExprSetHeight(A);
  }else{
    sqlite3ExprListDelete(Y);
  }
  sqlite3ExprSpan(A, &C, &E);
}
%type case_exprlist {ExprList*}
%destructor case_exprlist {sqlite3ExprListDelete($$);}
case_exprlist(A) ::= case_exprlist(X) WHEN expr(Y) THEN expr(Z). {
  A = sqlite3ExprListAppend(X, Y, 0);
  A = sqlite3ExprListAppend(A, Z, 0);
}
case_exprlist(A) ::= WHEN expr(Y) THEN expr(Z). {
  A = sqlite3ExprListAppend(0, Y, 0);
  A = sqlite3ExprListAppend(A, Z, 0);
}
%type case_else {Expr*}
%destructor case_else {sqlite3ExprDelete($$);}
case_else(A) ::=  ELSE expr(X).         {A = X;}
case_else(A) ::=  .                     {A = 0;} 
%type case_operand {Expr*}
%destructor case_operand {sqlite3ExprDelete($$);}
................................................................................
%type exprlist {ExprList*}
%destructor exprlist {sqlite3ExprListDelete($$);}
%type nexprlist {ExprList*}
%destructor nexprlist {sqlite3ExprListDelete($$);}

exprlist(A) ::= nexprlist(X).                {A = X;}
exprlist(A) ::= .                            {A = 0;}
nexprlist(A) ::= nexprlist(X) COMMA expr(Y). {A = sqlite3ExprListAppend(X,Y,0);}

nexprlist(A) ::= expr(Y).                    {A = sqlite3ExprListAppend(0,Y,0);}



///////////////////////////// The CREATE INDEX command ///////////////////////
//
cmd ::= CREATE(S) uniqueflag(U) INDEX ifnotexists(NE) nm(X) dbnm(D)
        ON nm(Y) LP idxlist(Z) RP(E). {
  sqlite3CreateIndex(pParse, &X, &D, sqlite3SrcListAppend(0,&Y,0), Z, U,

                      &S, &E, SQLITE_SO_ASC, NE);
}

%type uniqueflag {int}
uniqueflag(A) ::= UNIQUE.  {A = OE_Abort;}
uniqueflag(A) ::= .        {A = OE_None;}

................................................................................
%type idxitem {Token}

idxlist_opt(A) ::= .                         {A = 0;}
idxlist_opt(A) ::= LP idxlist(X) RP.         {A = X;}
idxlist(A) ::= idxlist(X) COMMA idxitem(Y) collate(C) sortorder(Z).  {
  Expr *p = 0;
  if( C.n>0 ){
    p = sqlite3Expr(TK_COLUMN, 0, 0, 0);
    if( p ) p->pColl = sqlite3LocateCollSeq(pParse, (char*)C.z, C.n);
  }
  A = sqlite3ExprListAppend(X, p, &Y);
  sqlite3ExprListCheckLength(pParse, A, SQLITE_MAX_COLUMN, "index");
  if( A ) A->a[A->nExpr-1].sortOrder = Z;
}
idxlist(A) ::= idxitem(Y) collate(C) sortorder(Z). {
  Expr *p = 0;
  if( C.n>0 ){
    p = sqlite3Expr(TK_COLUMN, 0, 0, 0);
    if( p ) p->pColl = sqlite3LocateCollSeq(pParse, (char*)C.z, C.n);
  }
  A = sqlite3ExprListAppend(0, p, &Y);
  sqlite3ExprListCheckLength(pParse, A, SQLITE_MAX_COLUMN, "index");
  if( A ) A->a[A->nExpr-1].sortOrder = Z;
}
idxitem(A) ::= nm(X).              {A = X;}

%type collate {Token}
collate(C) ::= .                {C.z = 0; C.n = 0;}
................................................................................
}
trigger_cmd_list(A) ::= . { A = 0; }

%type trigger_cmd {TriggerStep*}
%destructor trigger_cmd {sqlite3DeleteTriggerStep($$);}
// UPDATE 
trigger_cmd(A) ::= UPDATE orconf(R) nm(X) SET setlist(Y) where_opt(Z).  
               { A = sqlite3TriggerUpdateStep(&X, Y, Z, R); }

// INSERT
trigger_cmd(A) ::= insert_cmd(R) INTO nm(X) inscollist_opt(F) 
                   VALUES LP itemlist(Y) RP.  
               {A = sqlite3TriggerInsertStep(&X, F, Y, 0, R);}

trigger_cmd(A) ::= insert_cmd(R) INTO nm(X) inscollist_opt(F) select(S).
               {A = sqlite3TriggerInsertStep(&X, F, 0, S, R);}

// DELETE
trigger_cmd(A) ::= DELETE FROM nm(X) where_opt(Y).
               {A = sqlite3TriggerDeleteStep(&X, Y);}

// SELECT
trigger_cmd(A) ::= select(X).  {A = sqlite3TriggerSelectStep(X); }

// The special RAISE expression that may occur in trigger programs
expr(A) ::= RAISE(X) LP IGNORE RP(Y).  {
  A = sqlite3Expr(TK_RAISE, 0, 0, 0); 
  if( A ){
    A->iColumn = OE_Ignore;
    sqlite3ExprSpan(A, &X, &Y);
  }
}
expr(A) ::= RAISE(X) LP raisetype(T) COMMA nm(Z) RP(Y).  {
  A = sqlite3Expr(TK_RAISE, 0, 0, &Z); 
  if( A ) {
    A->iColumn = T;
    sqlite3ExprSpan(A, &X, &Y);
  }
}
%endif  !SQLITE_OMIT_TRIGGER

**
*************************************************************************
** This file contains SQLite's grammar for SQL.  Process this file
** using the lemon parser generator to generate C code that runs
** the parser.  Lemon will also generate a header file containing
** numeric codes for all of the tokens.
**
** @(#) $Id: parse.y,v 1.232 2007/08/16 04:30:40 drh Exp $
*/

// All token codes are small integers with #defines that begin with "TK_"
%token_prefix TK_

// The type of the data attached to each token is Token.  This is also the
// default type for non-terminals.
................................................................................
carglist ::= .
carg ::= CONSTRAINT nm ccons.
carg ::= ccons.
ccons ::= DEFAULT term(X).            {sqlite3AddDefaultValue(pParse,X);}
ccons ::= DEFAULT LP expr(X) RP.      {sqlite3AddDefaultValue(pParse,X);}
ccons ::= DEFAULT PLUS term(X).       {sqlite3AddDefaultValue(pParse,X);}
ccons ::= DEFAULT MINUS term(X).      {
  Expr *p = sqlite3PExpr(pParse, TK_UMINUS, X, 0, 0);
  sqlite3AddDefaultValue(pParse,p);
}
ccons ::= DEFAULT id(X).              {
  Expr *p = sqlite3PExpr(pParse, TK_STRING, 0, 0, &X);
  sqlite3AddDefaultValue(pParse,p);
}

// In addition to the type name, we also care about the primary key and
// UNIQUE constraints.
//
ccons ::= NULL onconf.
................................................................................
%type multiselect_op {int}
multiselect_op(A) ::= UNION(OP).             {A = @OP;}
multiselect_op(A) ::= UNION ALL.             {A = TK_ALL;}
multiselect_op(A) ::= EXCEPT|INTERSECT(OP).  {A = @OP;}
%endif SQLITE_OMIT_COMPOUND_SELECT
oneselect(A) ::= SELECT distinct(D) selcollist(W) from(X) where_opt(Y)
                 groupby_opt(P) having_opt(Q) orderby_opt(Z) limit_opt(L). {
  A = sqlite3SelectNew(pParse,W,X,Y,P,Q,Z,D,L.pLimit,L.pOffset);
}

// The "distinct" nonterminal is true (1) if the DISTINCT keyword is
// present and false (0) if it is not.
//
%type distinct {int}
distinct(A) ::= DISTINCT.   {A = 1;}
................................................................................
%type selcollist {ExprList*}
%destructor selcollist {sqlite3ExprListDelete($$);}
%type sclp {ExprList*}
%destructor sclp {sqlite3ExprListDelete($$);}
sclp(A) ::= selcollist(X) COMMA.             {A = X;}
sclp(A) ::= .                                {A = 0;}
selcollist(A) ::= sclp(P) expr(X) as(Y).     {
   A = sqlite3ExprListAppend(pParse,P,X,Y.n?&Y:0);
}
selcollist(A) ::= sclp(P) STAR. {
  Expr *p = sqlite3Expr(pParse, TK_ALL, 0, 0, 0);
  A = sqlite3ExprListAppend(pParse, P, p, 0);
}
selcollist(A) ::= sclp(P) nm(X) DOT STAR. {
  Expr *pRight = sqlite3PExpr(pParse, TK_ALL, 0, 0, 0);
  Expr *pLeft = sqlite3PExpr(pParse, TK_ID, 0, 0, &X);
  Expr *pDot = sqlite3PExpr(pParse, TK_DOT, pLeft, pRight, 0);
  A = sqlite3ExprListAppend(pParse,P, pDot, 0);
}

// An option "AS <id>" phrase that can follow one of the expressions that
// define the result set, or one of the tables in the FROM clause.
//
%type as {Token}
as(X) ::= AS nm(Y).    {X = Y;}
................................................................................
%type stl_prefix {SrcList*}
%destructor stl_prefix {sqlite3SrcListDelete($$);}
%type from {SrcList*}
%destructor from {sqlite3SrcListDelete($$);}

// A complete FROM clause.
//
from(A) ::= .                {A = sqlite3DbMallocZero(pParse->db, sizeof(*A));}
from(A) ::= FROM seltablist(X).  {
  A = X;
  sqlite3SrcListShiftJoinType(A);
}

// "seltablist" is a "Select Table List" - the content of the FROM clause
// in a SELECT statement.  "stl_prefix" is a prefix of this list.
//
stl_prefix(A) ::= seltablist(X) joinop(Y).    {
   A = X;
   if( A && A->nSrc>0 ) A->a[A->nSrc-1].jointype = Y;
}
stl_prefix(A) ::= .                           {A = 0;}
seltablist(A) ::= stl_prefix(X) nm(Y) dbnm(D) as(Z) on_opt(N) using_opt(U). {
  A = sqlite3SrcListAppendFromTerm(pParse,X,&Y,&D,&Z,0,N,U);
}
%ifndef SQLITE_OMIT_SUBQUERY
  seltablist(A) ::= stl_prefix(X) LP seltablist_paren(S) RP
                    as(Z) on_opt(N) using_opt(U). {
    A = sqlite3SrcListAppendFromTerm(pParse,X,0,0,&Z,S,N,U);
  }
  
  // A seltablist_paren nonterminal represents anything in a FROM that
  // is contained inside parentheses.  This can be either a subquery or
  // a grouping of table and subqueries.
  //
  %type seltablist_paren {Select*}
  %destructor seltablist_paren {sqlite3SelectDelete($$);}
  seltablist_paren(A) ::= select(S).      {A = S;}
  seltablist_paren(A) ::= seltablist(F).  {
     sqlite3SrcListShiftJoinType(F);
     A = sqlite3SelectNew(pParse,0,F,0,0,0,0,0,0,0);
  }
%endif  SQLITE_OMIT_SUBQUERY

%type dbnm {Token}
dbnm(A) ::= .          {A.z=0; A.n=0;}
dbnm(A) ::= DOT nm(X). {A = X;}

%type fullname {SrcList*}
%destructor fullname {sqlite3SrcListDelete($$);}
fullname(A) ::= nm(X) dbnm(Y).  {A = sqlite3SrcListAppend(pParse->db,0,&X,&Y);}

%type joinop {int}
%type joinop2 {int}
joinop(X) ::= COMMA|JOIN.              { X = JT_INNER; }
joinop(X) ::= JOIN_KW(A) JOIN.         { X = sqlite3JoinType(pParse,&A,0,0); }
joinop(X) ::= JOIN_KW(A) nm(B) JOIN.   { X = sqlite3JoinType(pParse,&A,&B,0); }
joinop(X) ::= JOIN_KW(A) nm(B) nm(C) JOIN.
................................................................................
%destructor sortlist {sqlite3ExprListDelete($$);}
%type sortitem {Expr*}
%destructor sortitem {sqlite3ExprDelete($$);}

orderby_opt(A) ::= .                          {A = 0;}
orderby_opt(A) ::= ORDER BY sortlist(X).      {A = X;}
sortlist(A) ::= sortlist(X) COMMA sortitem(Y) sortorder(Z). {
  A = sqlite3ExprListAppend(pParse,X,Y,0);
  if( A ) A->a[A->nExpr-1].sortOrder = Z;
}
sortlist(A) ::= sortitem(Y) sortorder(Z). {
  A = sqlite3ExprListAppend(pParse,0,Y,0);
  if( A && A->a ) A->a[0].sortOrder = Z;
}
sortitem(A) ::= expr(X).   {A = X;}

%type sortorder {int}

sortorder(A) ::= ASC.           {A = SQLITE_SO_ASC;}
................................................................................
  sqlite3Update(pParse,X,Y,Z,R);
}

%type setlist {ExprList*}
%destructor setlist {sqlite3ExprListDelete($$);}

setlist(A) ::= setlist(Z) COMMA nm(X) EQ expr(Y).
    {A = sqlite3ExprListAppend(pParse,Z,Y,&X);}
setlist(A) ::= nm(X) EQ expr(Y).
    {A = sqlite3ExprListAppend(pParse,0,Y,&X);}

////////////////////////// The INSERT command /////////////////////////////////
//
cmd ::= insert_cmd(R) INTO fullname(X) inscollist_opt(F) 
        VALUES LP itemlist(Y) RP.
            {sqlite3Insert(pParse, X, Y, 0, F, R);}
cmd ::= insert_cmd(R) INTO fullname(X) inscollist_opt(F) select(S).
................................................................................
insert_cmd(A) ::= INSERT orconf(R).   {A = R;}
insert_cmd(A) ::= REPLACE.            {A = OE_Replace;}


%type itemlist {ExprList*}
%destructor itemlist {sqlite3ExprListDelete($$);}

itemlist(A) ::= itemlist(X) COMMA expr(Y).
    {A = sqlite3ExprListAppend(pParse,X,Y,0);}
itemlist(A) ::= expr(X).
    {A = sqlite3ExprListAppend(pParse,0,X,0);}

%type inscollist_opt {IdList*}
%destructor inscollist_opt {sqlite3IdListDelete($$);}
%type inscollist {IdList*}
%destructor inscollist {sqlite3IdListDelete($$);}

inscollist_opt(A) ::= .                       {A = 0;}
inscollist_opt(A) ::= LP inscollist(X) RP.    {A = X;}
inscollist(A) ::= inscollist(X) COMMA nm(Y).
    {A = sqlite3IdListAppend(pParse->db,X,&Y);}
inscollist(A) ::= nm(Y).
    {A = sqlite3IdListAppend(pParse->db,0,&Y);}

/////////////////////////// Expression Processing /////////////////////////////
//

%type expr {Expr*}
%destructor expr {sqlite3ExprDelete($$);}
%type term {Expr*}
%destructor term {sqlite3ExprDelete($$);}

expr(A) ::= term(X).             {A = X;}
expr(A) ::= LP(B) expr(X) RP(E). {A = X; sqlite3ExprSpan(A,&B,&E); }
term(A) ::= NULL(X).             {A = sqlite3PExpr(pParse, @X, 0, 0, &X);}
expr(A) ::= ID(X).               {A = sqlite3PExpr(pParse, TK_ID, 0, 0, &X);}
expr(A) ::= JOIN_KW(X).          {A = sqlite3PExpr(pParse, TK_ID, 0, 0, &X);}
expr(A) ::= nm(X) DOT nm(Y). {
  Expr *temp1 = sqlite3PExpr(pParse, TK_ID, 0, 0, &X);
  Expr *temp2 = sqlite3PExpr(pParse, TK_ID, 0, 0, &Y);
  A = sqlite3PExpr(pParse, TK_DOT, temp1, temp2, 0);
}
expr(A) ::= nm(X) DOT nm(Y) DOT nm(Z). {
  Expr *temp1 = sqlite3PExpr(pParse, TK_ID, 0, 0, &X);
  Expr *temp2 = sqlite3PExpr(pParse, TK_ID, 0, 0, &Y);
  Expr *temp3 = sqlite3PExpr(pParse, TK_ID, 0, 0, &Z);
  Expr *temp4 = sqlite3PExpr(pParse, TK_DOT, temp2, temp3, 0);
  A = sqlite3PExpr(pParse, TK_DOT, temp1, temp4, 0);
}
term(A) ::= INTEGER|FLOAT|BLOB(X).      {A = sqlite3PExpr(pParse, @X, 0, 0, &X);}
term(A) ::= STRING(X).       {A = sqlite3PExpr(pParse, @X, 0, 0, &X);}
expr(A) ::= REGISTER(X).     {A = sqlite3RegisterExpr(pParse, &X);}
expr(A) ::= VARIABLE(X).     {
  Token *pToken = &X;
  Expr *pExpr = A = sqlite3PExpr(pParse, TK_VARIABLE, 0, 0, pToken);
  sqlite3ExprAssignVarNumber(pParse, pExpr);
}
expr(A) ::= expr(E) COLLATE id(C). {
  A = sqlite3ExprSetColl(pParse, E, &C);
}
%ifndef SQLITE_OMIT_CAST
expr(A) ::= CAST(X) LP expr(E) AS typetoken(T) RP(Y). {
  A = sqlite3PExpr(pParse, TK_CAST, E, 0, &T);
  sqlite3ExprSpan(A,&X,&Y);
}
%endif  SQLITE_OMIT_CAST
expr(A) ::= ID(X) LP distinct(D) exprlist(Y) RP(E). {
  if( Y && Y->nExpr>SQLITE_MAX_FUNCTION_ARG ){
    sqlite3ErrorMsg(pParse, "too many arguments on function %T", &X);
  }
  A = sqlite3ExprFunction(pParse, Y, &X);
  sqlite3ExprSpan(A,&X,&E);
  if( D && A ){
    A->flags |= EP_Distinct;
  }
}
expr(A) ::= ID(X) LP STAR RP(E). {
  A = sqlite3ExprFunction(pParse, 0, &X);
  sqlite3ExprSpan(A,&X,&E);
}
term(A) ::= CTIME_KW(OP). {
  /* The CURRENT_TIME, CURRENT_DATE, and CURRENT_TIMESTAMP values are
  ** treated as functions that return constants */
  A = sqlite3ExprFunction(pParse, 0,&OP);
  if( A ){
    A->op = TK_CONST_FUNC;  
    A->span = OP;
  }
}
expr(A) ::= expr(X) AND(OP) expr(Y).       {A = sqlite3PExpr(pParse,@OP,X,Y,0);}
expr(A) ::= expr(X) OR(OP) expr(Y).        {A = sqlite3PExpr(pParse,@OP,X,Y,0);}
expr(A) ::= expr(X) LT|GT|GE|LE(OP) expr(Y).
                                           {A = sqlite3PExpr(pParse,@OP,X,Y,0);}
expr(A) ::= expr(X) EQ|NE(OP) expr(Y).     {A = sqlite3PExpr(pParse,@OP,X,Y,0);}
expr(A) ::= expr(X) BITAND|BITOR|LSHIFT|RSHIFT(OP) expr(Y).

                                           {A = sqlite3PExpr(pParse,@OP,X,Y,0);}
expr(A) ::= expr(X) PLUS|MINUS(OP) expr(Y).{A = sqlite3PExpr(pParse,@OP,X,Y,0);}
expr(A) ::= expr(X) STAR|SLASH|REM(OP) expr(Y).
                                           {A = sqlite3PExpr(pParse,@OP,X,Y,0);}
expr(A) ::= expr(X) CONCAT(OP) expr(Y).    {A = sqlite3PExpr(pParse,@OP,X,Y,0);}
%type likeop {struct LikeOp}
likeop(A) ::= LIKE_KW(X).     {A.eOperator = X; A.not = 0;}
likeop(A) ::= NOT LIKE_KW(X). {A.eOperator = X; A.not = 1;}
likeop(A) ::= MATCH(X).       {A.eOperator = X; A.not = 0;}
likeop(A) ::= NOT MATCH(X).   {A.eOperator = X; A.not = 1;}
%type escape {Expr*}
%destructor escape {sqlite3ExprDelete($$);}
escape(X) ::= ESCAPE expr(A). [ESCAPE] {X = A;}
escape(X) ::= .               [ESCAPE] {X = 0;}
expr(A) ::= expr(X) likeop(OP) expr(Y) escape(E).  [LIKE_KW]  {
  ExprList *pList;
  pList = sqlite3ExprListAppend(pParse,0, Y, 0);
  pList = sqlite3ExprListAppend(pParse,pList, X, 0);
  if( E ){
    pList = sqlite3ExprListAppend(pParse,pList, E, 0);
  }
  A = sqlite3ExprFunction(pParse, pList, &OP.eOperator);
  if( OP.not ) A = sqlite3PExpr(pParse, TK_NOT, A, 0, 0);
  sqlite3ExprSpan(A, &X->span, &Y->span);
  if( A ) A->flags |= EP_InfixFunc;
}

expr(A) ::= expr(X) ISNULL|NOTNULL(E). {
  A = sqlite3PExpr(pParse, @E, X, 0, 0);
  sqlite3ExprSpan(A,&X->span,&E);
}
expr(A) ::= expr(X) IS NULL(E). {
  A = sqlite3PExpr(pParse, TK_ISNULL, X, 0, 0);
  sqlite3ExprSpan(A,&X->span,&E);
}
expr(A) ::= expr(X) NOT NULL(E). {
  A = sqlite3PExpr(pParse, TK_NOTNULL, X, 0, 0);
  sqlite3ExprSpan(A,&X->span,&E);
}
expr(A) ::= expr(X) IS NOT NULL(E). {
  A = sqlite3PExpr(pParse, TK_NOTNULL, X, 0, 0);
  sqlite3ExprSpan(A,&X->span,&E);
}
expr(A) ::= NOT|BITNOT(B) expr(X). {
  A = sqlite3PExpr(pParse, @B, X, 0, 0);
  sqlite3ExprSpan(A,&B,&X->span);
}
expr(A) ::= MINUS(B) expr(X). [UMINUS] {
  A = sqlite3PExpr(pParse, TK_UMINUS, X, 0, 0);
  sqlite3ExprSpan(A,&B,&X->span);
}
expr(A) ::= PLUS(B) expr(X). [UPLUS] {
  A = sqlite3PExpr(pParse, TK_UPLUS, X, 0, 0);
  sqlite3ExprSpan(A,&B,&X->span);
}
%type between_op {int}
between_op(A) ::= BETWEEN.     {A = 0;}
between_op(A) ::= NOT BETWEEN. {A = 1;}
expr(A) ::= expr(W) between_op(N) expr(X) AND expr(Y). [BETWEEN] {
  ExprList *pList = sqlite3ExprListAppend(pParse,0, X, 0);
  pList = sqlite3ExprListAppend(pParse,pList, Y, 0);
  A = sqlite3PExpr(pParse, TK_BETWEEN, W, 0, 0);
  if( A ){
    A->pList = pList;
  }else{
    sqlite3ExprListDelete(pList);
  } 
  if( N ) A = sqlite3PExpr(pParse, TK_NOT, A, 0, 0);
  sqlite3ExprSpan(A,&W->span,&Y->span);
}
%ifndef SQLITE_OMIT_SUBQUERY
  %type in_op {int}
  in_op(A) ::= IN.      {A = 0;}
  in_op(A) ::= NOT IN.  {A = 1;}
  expr(A) ::= expr(X) in_op(N) LP exprlist(Y) RP(E). [IN] {
    A = sqlite3PExpr(pParse, TK_IN, X, 0, 0);
    if( A ){
      A->pList = Y;
      sqlite3ExprSetHeight(A);
    }else{
      sqlite3ExprListDelete(Y);
    }
    if( N ) A = sqlite3PExpr(pParse, TK_NOT, A, 0, 0);
    sqlite3ExprSpan(A,&X->span,&E);
  }
  expr(A) ::= LP(B) select(X) RP(E). {
    A = sqlite3PExpr(pParse, TK_SELECT, 0, 0, 0);
    if( A ){
      A->pSelect = X;
      sqlite3ExprSetHeight(A);
    }else{
      sqlite3SelectDelete(X);
    }
    sqlite3ExprSpan(A,&B,&E);
  }
  expr(A) ::= expr(X) in_op(N) LP select(Y) RP(E).  [IN] {
    A = sqlite3PExpr(pParse, TK_IN, X, 0, 0);
    if( A ){
      A->pSelect = Y;
      sqlite3ExprSetHeight(A);
    }else{
      sqlite3SelectDelete(Y);
    }
    if( N ) A = sqlite3PExpr(pParse, TK_NOT, A, 0, 0);
    sqlite3ExprSpan(A,&X->span,&E);
  }
  expr(A) ::= expr(X) in_op(N) nm(Y) dbnm(Z). [IN] {
    SrcList *pSrc = sqlite3SrcListAppend(pParse->db, 0,&Y,&Z);
    A = sqlite3PExpr(pParse, TK_IN, X, 0, 0);
    if( A ){
      A->pSelect = sqlite3SelectNew(0,pSrc,0,0,0,0,0,0,0);
      sqlite3ExprSetHeight(A);
    }else{
      sqlite3SrcListDelete(pSrc);
    }
    if( N ) A = sqlite3PExpr(pParse, TK_NOT, A, 0, 0);
    sqlite3ExprSpan(A,&X->span,Z.z?&Z:&Y);
  }
  expr(A) ::= EXISTS(B) LP select(Y) RP(E). {
    Expr *p = A = sqlite3PExpr(pParse, TK_EXISTS, 0, 0, 0);
    if( p ){
      p->pSelect = Y;
      sqlite3ExprSpan(p,&B,&E);
      sqlite3ExprSetHeight(A);
    }else{
      sqlite3SelectDelete(Y);
    }
  }
%endif SQLITE_OMIT_SUBQUERY

/* CASE expressions */
expr(A) ::= CASE(C) case_operand(X) case_exprlist(Y) case_else(Z) END(E). {
  A = sqlite3PExpr(pParse, TK_CASE, X, Z, 0);
  if( A ){
    A->pList = Y;
    sqlite3ExprSetHeight(A);
  }else{
    sqlite3ExprListDelete(Y);
  }
  sqlite3ExprSpan(A, &C, &E);
}
%type case_exprlist {ExprList*}
%destructor case_exprlist {sqlite3ExprListDelete($$);}
case_exprlist(A) ::= case_exprlist(X) WHEN expr(Y) THEN expr(Z). {
  A = sqlite3ExprListAppend(pParse,X, Y, 0);
  A = sqlite3ExprListAppend(pParse,A, Z, 0);
}
case_exprlist(A) ::= WHEN expr(Y) THEN expr(Z). {
  A = sqlite3ExprListAppend(pParse,0, Y, 0);
  A = sqlite3ExprListAppend(pParse,A, Z, 0);
}
%type case_else {Expr*}
%destructor case_else {sqlite3ExprDelete($$);}
case_else(A) ::=  ELSE expr(X).         {A = X;}
case_else(A) ::=  .                     {A = 0;} 
%type case_operand {Expr*}
%destructor case_operand {sqlite3ExprDelete($$);}
................................................................................
%type exprlist {ExprList*}
%destructor exprlist {sqlite3ExprListDelete($$);}
%type nexprlist {ExprList*}
%destructor nexprlist {sqlite3ExprListDelete($$);}

exprlist(A) ::= nexprlist(X).                {A = X;}
exprlist(A) ::= .                            {A = 0;}
nexprlist(A) ::= nexprlist(X) COMMA expr(Y).
    {A = sqlite3ExprListAppend(pParse,X,Y,0);}
nexprlist(A) ::= expr(Y).
    {A = sqlite3ExprListAppend(pParse,0,Y,0);}


///////////////////////////// The CREATE INDEX command ///////////////////////
//
cmd ::= CREATE(S) uniqueflag(U) INDEX ifnotexists(NE) nm(X) dbnm(D)
        ON nm(Y) LP idxlist(Z) RP(E). {
  sqlite3CreateIndex(pParse, &X, &D, 
                     sqlite3SrcListAppend(pParse->db,0,&Y,0), Z, U,
                      &S, &E, SQLITE_SO_ASC, NE);
}

%type uniqueflag {int}
uniqueflag(A) ::= UNIQUE.  {A = OE_Abort;}
uniqueflag(A) ::= .        {A = OE_None;}

................................................................................
%type idxitem {Token}

idxlist_opt(A) ::= .                         {A = 0;}
idxlist_opt(A) ::= LP idxlist(X) RP.         {A = X;}
idxlist(A) ::= idxlist(X) COMMA idxitem(Y) collate(C) sortorder(Z).  {
  Expr *p = 0;
  if( C.n>0 ){
    p = sqlite3PExpr(pParse, TK_COLUMN, 0, 0, 0);
    if( p ) p->pColl = sqlite3LocateCollSeq(pParse, (char*)C.z, C.n);
  }
  A = sqlite3ExprListAppend(pParse,X, p, &Y);
  sqlite3ExprListCheckLength(pParse, A, SQLITE_MAX_COLUMN, "index");
  if( A ) A->a[A->nExpr-1].sortOrder = Z;
}
idxlist(A) ::= idxitem(Y) collate(C) sortorder(Z). {
  Expr *p = 0;
  if( C.n>0 ){
    p = sqlite3PExpr(pParse, TK_COLUMN, 0, 0, 0);
    if( p ) p->pColl = sqlite3LocateCollSeq(pParse, (char*)C.z, C.n);
  }
  A = sqlite3ExprListAppend(pParse,0, p, &Y);
  sqlite3ExprListCheckLength(pParse, A, SQLITE_MAX_COLUMN, "index");
  if( A ) A->a[A->nExpr-1].sortOrder = Z;
}
idxitem(A) ::= nm(X).              {A = X;}

%type collate {Token}
collate(C) ::= .                {C.z = 0; C.n = 0;}
................................................................................
}
trigger_cmd_list(A) ::= . { A = 0; }

%type trigger_cmd {TriggerStep*}
%destructor trigger_cmd {sqlite3DeleteTriggerStep($$);}
// UPDATE 
trigger_cmd(A) ::= UPDATE orconf(R) nm(X) SET setlist(Y) where_opt(Z).  
               { A = sqlite3TriggerUpdateStep(pParse->db, &X, Y, Z, R); }

// INSERT
trigger_cmd(A) ::= insert_cmd(R) INTO nm(X) inscollist_opt(F) 
                   VALUES LP itemlist(Y) RP.  
               {A = sqlite3TriggerInsertStep(pParse->db, &X, F, Y, 0, R);}

trigger_cmd(A) ::= insert_cmd(R) INTO nm(X) inscollist_opt(F) select(S).
               {A = sqlite3TriggerInsertStep(pParse->db, &X, F, 0, S, R);}

// DELETE
trigger_cmd(A) ::= DELETE FROM nm(X) where_opt(Y).
               {A = sqlite3TriggerDeleteStep(pParse->db, &X, Y);}

// SELECT
trigger_cmd(A) ::= select(X).  {A = sqlite3TriggerSelectStep(pParse->db, X); }

// The special RAISE expression that may occur in trigger programs
expr(A) ::= RAISE(X) LP IGNORE RP(Y).  {
  A = sqlite3PExpr(pParse, TK_RAISE, 0, 0, 0); 
  if( A ){
    A->iColumn = OE_Ignore;
    sqlite3ExprSpan(A, &X, &Y);
  }
}
expr(A) ::= RAISE(X) LP raisetype(T) COMMA nm(Z) RP(Y).  {
  A = sqlite3PExpr(pParse, TK_RAISE, 0, 0, &Z); 
  if( A ) {
    A->iColumn = T;
    sqlite3ExprSpan(A, &X, &Y);
  }
}
%endif  !SQLITE_OMIT_TRIGGER

**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains code used to implement the PRAGMA command.
**
** $Id: pragma.c,v 1.142 2007/06/26 10:38:55 danielk1977 Exp $
*/
#include "sqliteInt.h"
#include "os.h"
#include <ctype.h>

/* Ignore this whole file if pragmas are disabled
*/
................................................................................
  /* If the temp database has been explicitly named as part of the 
  ** pragma, make sure it is open. 
  */
  if( iDb==1 && sqlite3OpenTempDatabase(pParse) ){
    return;
  }

  zLeft = sqlite3NameFromToken(pId);
  if( !zLeft ) return;
  if( minusFlag ){
    zRight = sqlite3MPrintf("-%T", pValue);
  }else{
    zRight = sqlite3NameFromToken(pValue);
  }

  zDb = ((iDb>0)?pDb->zName:0);
  if( sqlite3AuthCheck(pParse, SQLITE_PRAGMA, zLeft, zRight, zDb) ){
    goto pragma_out;
  }
 
................................................................................
      }
      if( TEMP_STORE==0
       || (TEMP_STORE==1 && db->temp_store<=1)
       || (TEMP_STORE==2 && db->temp_store==1)
      ){
        invalidateTempStorage(pParse);
      }
      sqliteFree(sqlite3_temp_directory);
      if( zRight[0] ){
        sqlite3_temp_directory = zRight;
        zRight = 0;
      }else{
        sqlite3_temp_directory = 0;
      }
    }
................................................................................
    if( db->autoCommit ){
      sqlite3BtreeSetSafetyLevel(pDb->pBt, pDb->safety_level,
                 (db->flags&SQLITE_FullFSync)!=0);
    }
#endif
  }
pragma_out:
  sqliteFree(zLeft);
  sqliteFree(zRight);
}

#endif /* SQLITE_OMIT_PRAGMA || SQLITE_OMIT_PARSER */

**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains code used to implement the PRAGMA command.
**
** $Id: pragma.c,v 1.143 2007/08/16 04:30:40 drh Exp $
*/
#include "sqliteInt.h"
#include "os.h"
#include <ctype.h>

/* Ignore this whole file if pragmas are disabled
*/
................................................................................
  /* If the temp database has been explicitly named as part of the 
  ** pragma, make sure it is open. 
  */
  if( iDb==1 && sqlite3OpenTempDatabase(pParse) ){
    return;
  }

  zLeft = sqlite3NameFromToken(db, pId);
  if( !zLeft ) return;
  if( minusFlag ){
    zRight = sqlite3MPrintf(db, "-%T", pValue);
  }else{
    zRight = sqlite3NameFromToken(db, pValue);
  }

  zDb = ((iDb>0)?pDb->zName:0);
  if( sqlite3AuthCheck(pParse, SQLITE_PRAGMA, zLeft, zRight, zDb) ){
    goto pragma_out;
  }
 
................................................................................
      }
      if( TEMP_STORE==0
       || (TEMP_STORE==1 && db->temp_store<=1)
       || (TEMP_STORE==2 && db->temp_store==1)
      ){
        invalidateTempStorage(pParse);
      }
      sqlite3_free(sqlite3_temp_directory);
      if( zRight[0] ){
        sqlite3_temp_directory = zRight;
        zRight = 0;
      }else{
        sqlite3_temp_directory = 0;
      }
    }
................................................................................
    if( db->autoCommit ){
      sqlite3BtreeSetSafetyLevel(pDb->pBt, pDb->safety_level,
                 (db->flags&SQLITE_FullFSync)!=0);
    }
#endif
  }
pragma_out:
  sqlite3_free(zLeft);
  sqlite3_free(zRight);
}

#endif /* SQLITE_OMIT_PRAGMA || SQLITE_OMIT_PARSER */

**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains the implementation of the sqlite3_prepare()
** interface, and routines that contribute to loading the database schema
** from disk.
**
** $Id: prepare.c,v 1.52 2007/08/13 14:41:19 danielk1977 Exp $
*/
#include "sqliteInt.h"
#include "os.h"
#include <ctype.h>

/*
** Fill the InitData structure with an error message that indicates
** that the database is corrupt.
*/
static void corruptSchema(InitData *pData, const char *zExtra){
  if( !sqlite3MallocFailed() ){
    sqlite3SetString(pData->pzErrMsg, "malformed database schema",
       zExtra!=0 && zExtra[0]!=0 ? " - " : (char*)0, zExtra, (char*)0);
  }
  pData->rc = SQLITE_CORRUPT;
}

/*
................................................................................
int sqlite3InitCallback(void *pInit, int argc, char **argv, char **azColName){
  InitData *pData = (InitData*)pInit;
  sqlite3 *db = pData->db;
  int iDb = pData->iDb;

  pData->rc = SQLITE_OK;
  DbClearProperty(db, iDb, DB_Empty);
  if( sqlite3MallocFailed() ){
    corruptSchema(pData, 0);
    return SQLITE_NOMEM;
  }

  assert( argc==3 );
  if( argv==0 ) return 0;   /* Might happen if EMPTY_RESULT_CALLBACKS are on */
  if( argv[1]==0 ){
................................................................................
    db->init.newTnum = atoi(argv[1]);
    rc = sqlite3_exec(db, argv[2], 0, 0, &zErr);
    db->init.iDb = 0;
    assert( rc!=SQLITE_OK || zErr==0 );
    if( SQLITE_OK!=rc ){
      pData->rc = rc;
      if( rc==SQLITE_NOMEM ){
        sqlite3FailedMalloc();
      }else if( rc!=SQLITE_INTERRUPT ){
        corruptSchema(pData, zErr);
      }
      sqlite3_free(zErr);
      return 1;
    }
  }else{
................................................................................
    zSql = sqlite3MPrintf(
        "SELECT name, rootpage, sql FROM '%q'.%s",
        db->aDb[iDb].zName, zMasterName);
    sqlite3SafetyOff(db);
    rc = sqlite3_exec(db, zSql, sqlite3InitCallback, &initData, 0);
    if( rc==SQLITE_ABORT ) rc = initData.rc;
    sqlite3SafetyOn(db);
    sqliteFree(zSql);
#ifndef SQLITE_OMIT_ANALYZE
    if( rc==SQLITE_OK ){
      sqlite3AnalysisLoad(db, iDb);
    }
#endif
    sqlite3BtreeCloseCursor(curMain);
  }
  if( sqlite3MallocFailed() ){
    /* sqlite3SetString(pzErrMsg, "out of memory", (char*)0); */
    rc = SQLITE_NOMEM;
    sqlite3ResetInternalSchema(db, 0);
  }
  if( rc==SQLITE_OK || (db->flags&SQLITE_RecoveryMode)){
    /* Black magic: If the SQLITE_RecoveryMode flag is set, then consider
    ** the schema loaded, even if errors occured. In this situation the 
................................................................................
){
  Parse sParse;
  char *zErrMsg = 0;
  int rc = SQLITE_OK;
  int i;

  /* Assert that malloc() has not failed */
  assert( !sqlite3MallocFailed() );

  assert( ppStmt );
  *ppStmt = 0;
  if( sqlite3SafetyOn(db) ){
    return SQLITE_MISUSE;
  }

................................................................................
  memset(&sParse, 0, sizeof(sParse));
  sParse.db = db;
  if( nBytes>=0 && zSql[nBytes]!=0 ){
    char *zSqlCopy;
    if( nBytes>SQLITE_MAX_SQL_LENGTH ){
      return SQLITE_TOOBIG;
    }
    zSqlCopy = sqlite3StrNDup(zSql, nBytes);
    if( zSqlCopy ){
      sqlite3RunParser(&sParse, zSqlCopy, &zErrMsg);
      sqliteFree(zSqlCopy);
    }
    sParse.zTail = &zSql[nBytes];
  }else{
    sqlite3RunParser(&sParse, zSql, &zErrMsg);
  }

  if( sqlite3MallocFailed() ){
    sParse.rc = SQLITE_NOMEM;
  }
  if( sParse.rc==SQLITE_DONE ) sParse.rc = SQLITE_OK;
  if( sParse.checkSchema && !schemaIsValid(db) ){
    sParse.rc = SQLITE_SCHEMA;
  }
  if( sParse.rc==SQLITE_SCHEMA ){
    sqlite3ResetInternalSchema(db, 0);
  }
  if( sqlite3MallocFailed() ){
    sParse.rc = SQLITE_NOMEM;
  }
  if( pzTail ){
    *pzTail = sParse.zTail;
  }
  rc = sParse.rc;

................................................................................
  if( sqlite3SafetyOff(db) ){
    rc = SQLITE_MISUSE;
  }

  if( saveSqlFlag ){
    sqlite3VdbeSetSql(sParse.pVdbe, zSql, sParse.zTail - zSql);
  }
  if( rc!=SQLITE_OK || sqlite3MallocFailed() ){
    sqlite3_finalize((sqlite3_stmt*)sParse.pVdbe);
    assert(!(*ppStmt));
  }else{
    *ppStmt = (sqlite3_stmt*)sParse.pVdbe;
  }

  if( zErrMsg ){
    sqlite3Error(db, rc, "%s", zErrMsg);
    sqliteFree(zErrMsg);
  }else{
    sqlite3Error(db, rc, 0);
  }

  rc = sqlite3ApiExit(db, rc);
  sqlite3ReleaseThreadData();
  assert( (rc&db->errMask)==rc );
................................................................................
    ** equivalent pointer into the UTF-16 string by counting the unicode
    ** characters between zSql8 and zTail8, and then returning a pointer
    ** the same number of characters into the UTF-16 string.
    */
    int chars_parsed = sqlite3Utf8CharLen(zSql8, zTail8-zSql8);
    *pzTail = (u8 *)zSql + sqlite3Utf16ByteLen(zSql, chars_parsed);
  }
  sqliteFree(zSql8); 
  return sqlite3ApiExit(db, rc);
}

/*
** Two versions of the official API.  Legacy and new use.  In the legacy
** version, the original SQL text is not saved in the prepared statement
** and so if a schema change occurs, SQLITE_SCHEMA is returned by

**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains the implementation of the sqlite3_prepare()
** interface, and routines that contribute to loading the database schema
** from disk.
**
** $Id: prepare.c,v 1.53 2007/08/16 04:30:40 drh Exp $
*/
#include "sqliteInt.h"
#include "os.h"
#include <ctype.h>

/*
** Fill the InitData structure with an error message that indicates
** that the database is corrupt.
*/
static void corruptSchema(InitData *pData, const char *zExtra){
  if( !pData->db->mallocFailed ){
    sqlite3SetString(pData->pzErrMsg, "malformed database schema",
       zExtra!=0 && zExtra[0]!=0 ? " - " : (char*)0, zExtra, (char*)0);
  }
  pData->rc = SQLITE_CORRUPT;
}

/*
................................................................................
int sqlite3InitCallback(void *pInit, int argc, char **argv, char **azColName){
  InitData *pData = (InitData*)pInit;
  sqlite3 *db = pData->db;
  int iDb = pData->iDb;

  pData->rc = SQLITE_OK;
  DbClearProperty(db, iDb, DB_Empty);
  if( db->mallocFailed ){
    corruptSchema(pData, 0);
    return SQLITE_NOMEM;
  }

  assert( argc==3 );
  if( argv==0 ) return 0;   /* Might happen if EMPTY_RESULT_CALLBACKS are on */
  if( argv[1]==0 ){
................................................................................
    db->init.newTnum = atoi(argv[1]);
    rc = sqlite3_exec(db, argv[2], 0, 0, &zErr);
    db->init.iDb = 0;
    assert( rc!=SQLITE_OK || zErr==0 );
    if( SQLITE_OK!=rc ){
      pData->rc = rc;
      if( rc==SQLITE_NOMEM ){
        db->mallocFailed = 1;
      }else if( rc!=SQLITE_INTERRUPT ){
        corruptSchema(pData, zErr);
      }
      sqlite3_free(zErr);
      return 1;
    }
  }else{
................................................................................
    zSql = sqlite3MPrintf(
        "SELECT name, rootpage, sql FROM '%q'.%s",
        db->aDb[iDb].zName, zMasterName);
    sqlite3SafetyOff(db);
    rc = sqlite3_exec(db, zSql, sqlite3InitCallback, &initData, 0);
    if( rc==SQLITE_ABORT ) rc = initData.rc;
    sqlite3SafetyOn(db);
    sqlite3_free(zSql);
#ifndef SQLITE_OMIT_ANALYZE
    if( rc==SQLITE_OK ){
      sqlite3AnalysisLoad(db, iDb);
    }
#endif
    sqlite3BtreeCloseCursor(curMain);
  }
  if( db->mallocFailed ){
    /* sqlite3SetString(pzErrMsg, "out of memory", (char*)0); */
    rc = SQLITE_NOMEM;
    sqlite3ResetInternalSchema(db, 0);
  }
  if( rc==SQLITE_OK || (db->flags&SQLITE_RecoveryMode)){
    /* Black magic: If the SQLITE_RecoveryMode flag is set, then consider
    ** the schema loaded, even if errors occured. In this situation the 
................................................................................
){
  Parse sParse;
  char *zErrMsg = 0;
  int rc = SQLITE_OK;
  int i;

  /* Assert that malloc() has not failed */
  assert( !db->mallocFailed );

  assert( ppStmt );
  *ppStmt = 0;
  if( sqlite3SafetyOn(db) ){
    return SQLITE_MISUSE;
  }

................................................................................
  memset(&sParse, 0, sizeof(sParse));
  sParse.db = db;
  if( nBytes>=0 && zSql[nBytes]!=0 ){
    char *zSqlCopy;
    if( nBytes>SQLITE_MAX_SQL_LENGTH ){
      return SQLITE_TOOBIG;
    }
    zSqlCopy = sqlite3DbStrNDup(db, zSql, nBytes);
    if( zSqlCopy ){
      sqlite3RunParser(&sParse, zSqlCopy, &zErrMsg);
      sqlite3_free(zSqlCopy);
    }
    sParse.zTail = &zSql[nBytes];
  }else{
    sqlite3RunParser(&sParse, zSql, &zErrMsg);
  }

  if( db->mallocFailed ){
    sParse.rc = SQLITE_NOMEM;
  }
  if( sParse.rc==SQLITE_DONE ) sParse.rc = SQLITE_OK;
  if( sParse.checkSchema && !schemaIsValid(db) ){
    sParse.rc = SQLITE_SCHEMA;
  }
  if( sParse.rc==SQLITE_SCHEMA ){
    sqlite3ResetInternalSchema(db, 0);
  }
  if( db->mallocFailed ){
    sParse.rc = SQLITE_NOMEM;
  }
  if( pzTail ){
    *pzTail = sParse.zTail;
  }
  rc = sParse.rc;

................................................................................
  if( sqlite3SafetyOff(db) ){
    rc = SQLITE_MISUSE;
  }

  if( saveSqlFlag ){
    sqlite3VdbeSetSql(sParse.pVdbe, zSql, sParse.zTail - zSql);
  }
  if( rc!=SQLITE_OK || db->mallocFailed ){
    sqlite3_finalize((sqlite3_stmt*)sParse.pVdbe);
    assert(!(*ppStmt));
  }else{
    *ppStmt = (sqlite3_stmt*)sParse.pVdbe;
  }

  if( zErrMsg ){
    sqlite3Error(db, rc, "%s", zErrMsg);
    sqlite3_free(zErrMsg);
  }else{
    sqlite3Error(db, rc, 0);
  }

  rc = sqlite3ApiExit(db, rc);
  sqlite3ReleaseThreadData();
  assert( (rc&db->errMask)==rc );
................................................................................
    ** equivalent pointer into the UTF-16 string by counting the unicode
    ** characters between zSql8 and zTail8, and then returning a pointer
    ** the same number of characters into the UTF-16 string.
    */
    int chars_parsed = sqlite3Utf8CharLen(zSql8, zTail8-zSql8);
    *pzTail = (u8 *)zSql + sqlite3Utf16ByteLen(zSql, chars_parsed);
  }
  sqlite3_free(zSql8); 
  return sqlite3ApiExit(db, rc);
}

/*
** Two versions of the official API.  Legacy and new use.  In the legacy
** version, the original SQL text is not saved in the prepared statement
** and so if a schema change occurs, SQLITE_SCHEMA is returned by

        if( isnull ) escarg = (xtype==etSQLESCAPE2 ? "NULL" : "(NULL)");
        for(i=n=0; (ch=escarg[i])!=0; i++){
          if( ch==q )  n++;
        }
        needQuote = !isnull && xtype==etSQLESCAPE2;
        n += i + 1 + needQuote*2;
        if( n>etBUFSIZE ){
          bufpt = zExtra = sqliteMalloc( n );
          if( bufpt==0 ) return -1;
        }else{
          bufpt = buf;
        }
        j = 0;
        if( needQuote ) bufpt[j++] = q;
        for(i=0; (ch=escarg[i])!=0; i++){
................................................................................
**
** This routine add nNewChar characters of text in zNewText to
** the sgMprintf structure pointed to by "arg".
*/
static void mout(void *arg, const char *zNewText, int nNewChar){
  struct sgMprintf *pM = (struct sgMprintf*)arg;
  pM->nTotal += nNewChar;

  if( pM->nChar + nNewChar + 1 > pM->nAlloc ){
    if( pM->xRealloc==0 ){
      nNewChar =  pM->nAlloc - pM->nChar - 1;
    }else{
      int nAlloc = pM->nChar + nNewChar*2 + 1;
      if( pM->zText==pM->zBase ){
        pM->zText = pM->xRealloc(0, nAlloc);
        if( pM->zText && pM->nChar ){


          memcpy(pM->zText, pM->zBase, pM->nChar);
        }
      }else{
        char *zNew;
        zNew = pM->xRealloc(pM->zText, nAlloc);
        if( zNew ){
          pM->zText = zNew;
        }else{


          return;
        }
      }
      pM->nAlloc = nAlloc;
    }
  }
  if( pM->zText ){
    if( nNewChar>0 ){
      memcpy(&pM->zText[pM->nChar], zNewText, nNewChar);
      pM->nChar += nNewChar;
    }
    pM->zText[pM->nChar] = 0;
  }
}
................................................................................
  return sM.zText;
}

/*
** Realloc that is a real function, not a macro.
*/
static void *printf_realloc(void *old, int size){
  return sqliteRealloc(old,size);
}

/*
** Print into memory obtained from sqliteMalloc().  Use the internal
** %-conversion extensions.
*/
char *sqlite3VMPrintf(const char *zFormat, va_list ap){

  char zBase[SQLITE_PRINT_BUF_SIZE];
  return base_vprintf(printf_realloc, 1, zBase, sizeof(zBase), zFormat, ap);




}

/*
** Print into memory obtained from sqliteMalloc().  Use the internal
** %-conversion extensions.
*/
char *sqlite3MPrintf(const char *zFormat, ...){
  va_list ap;
  char *z;
  char zBase[SQLITE_PRINT_BUF_SIZE];
  va_start(ap, zFormat);
  z = base_vprintf(printf_realloc, 1, zBase, sizeof(zBase), zFormat, ap);
  va_end(ap);



  return z;
}

/*
** Print into memory obtained from sqlite3_malloc().  Omit the internal
** %-conversion extensions.
*/

        if( isnull ) escarg = (xtype==etSQLESCAPE2 ? "NULL" : "(NULL)");
        for(i=n=0; (ch=escarg[i])!=0; i++){
          if( ch==q )  n++;
        }
        needQuote = !isnull && xtype==etSQLESCAPE2;
        n += i + 1 + needQuote*2;
        if( n>etBUFSIZE ){
          bufpt = zExtra = sqlite3_malloc( n );
          if( bufpt==0 ) return -1;
        }else{
          bufpt = buf;
        }
        j = 0;
        if( needQuote ) bufpt[j++] = q;
        for(i=0; (ch=escarg[i])!=0; i++){
................................................................................
**
** This routine add nNewChar characters of text in zNewText to
** the sgMprintf structure pointed to by "arg".
*/
static void mout(void *arg, const char *zNewText, int nNewChar){
  struct sgMprintf *pM = (struct sgMprintf*)arg;
  pM->nTotal += nNewChar;
  if( pM->zText ){
    if( pM->nChar + nNewChar + 1 > pM->nAlloc ){
      if( pM->xRealloc==0 ){
        nNewChar =  pM->nAlloc - pM->nChar - 1;
      }else{
        int nAlloc = pM->nChar + nNewChar*2 + 1;
        if( pM->zText==pM->zBase ){
          pM->zText = pM->xRealloc(0, nAlloc);
          if( pM->zText==0 ){
            return;
          }else if( pM->nChar ){
            memcpy(pM->zText, pM->zBase, pM->nChar);
          }
        }else{
          char *zNew;
          zNew = pM->xRealloc(pM->zText, nAlloc);
          if( zNew ){
            pM->zText = zNew;
          }else{
            pM->xRealloc(pM->zText, 0);
            pM->zText = 0;
            return;
          }
        }
        pM->nAlloc = nAlloc;
      }
    }

    if( nNewChar>0 ){
      memcpy(&pM->zText[pM->nChar], zNewText, nNewChar);
      pM->nChar += nNewChar;
    }
    pM->zText[pM->nChar] = 0;
  }
}
................................................................................
  return sM.zText;
}

/*
** Realloc that is a real function, not a macro.
*/
static void *printf_realloc(void *old, int size){
  return sqlite3_realloc(old,size);
}

/*
** Print into memory obtained from sqliteMalloc().  Use the internal
** %-conversion extensions.
*/
char *sqlite3VMPrintf(sqlite3 *db, const char *zFormat, va_list ap){
  char *z;
  char zBase[SQLITE_PRINT_BUF_SIZE];
  z = base_vprintf(printf_realloc, 1, zBase, sizeof(zBase), zFormat, ap);
  if( z==0 && db!=0 ){
    db->mallocFailed = 1;
  }
  return z;
}

/*
** Print into memory obtained from sqliteMalloc().  Use the internal
** %-conversion extensions.
*/
char *sqlite3MPrintf(sqlite3 *db, const char *zFormat, ...){
  va_list ap;
  char *z;
  char zBase[SQLITE_PRINT_BUF_SIZE];
  va_start(ap, zFormat);
  z = base_vprintf(printf_realloc, 1, zBase, sizeof(zBase), zFormat, ap);
  va_end(ap);
  if( z==0 && db!=0 ){
    db->mallocFailed = 1;
  }
  return z;
}

/*
** Print into memory obtained from sqlite3_malloc().  Omit the internal
** %-conversion extensions.
*/

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains C code routines that are called by the parser
** to handle SELECT statements in SQLite.
**
** $Id: select.c,v 1.354 2007/07/18 18:17:12 drh Exp $
*/
#include "sqliteInt.h"


/*
** Delete all the content of a Select structure but do not deallocate
** the select structure itself.
................................................................................


/*
** Allocate a new Select structure and return a pointer to that
** structure.
*/
Select *sqlite3SelectNew(

  ExprList *pEList,     /* which columns to include in the result */
  SrcList *pSrc,        /* the FROM clause -- which tables to scan */
  Expr *pWhere,         /* the WHERE clause */
  ExprList *pGroupBy,   /* the GROUP BY clause */
  Expr *pHaving,        /* the HAVING clause */
  ExprList *pOrderBy,   /* the ORDER BY clause */
  int isDistinct,       /* true if the DISTINCT keyword is present */
  Expr *pLimit,         /* LIMIT value.  NULL means not used */
  Expr *pOffset         /* OFFSET value.  NULL means no offset */
){
  Select *pNew;
  Select standin;
  pNew = sqliteMalloc( sizeof(*pNew) );

  assert( !pOffset || pLimit );   /* Can't have OFFSET without LIMIT. */
  if( pNew==0 ){
    pNew = &standin;
    memset(pNew, 0, sizeof(*pNew));
  }
  if( pEList==0 ){
    pEList = sqlite3ExprListAppend(0, sqlite3Expr(TK_ALL,0,0,0), 0);
  }
  pNew->pEList = pEList;
  pNew->pSrc = pSrc;
  pNew->pWhere = pWhere;
  pNew->pGroupBy = pGroupBy;
  pNew->pHaving = pHaving;
  pNew->pOrderBy = pOrderBy;
................................................................................

/*
** Delete the given Select structure and all of its substructures.
*/
void sqlite3SelectDelete(Select *p){
  if( p ){
    clearSelect(p);
    sqliteFree(p);
  }
}

/*
** Given 1 to 3 identifiers preceeding the JOIN keyword, determine the
** type of join.  Return an integer constant that expresses that type
** in terms of the following bit values:
................................................................................
    p->n = strlen((char *)p->z);
  }
}

/*
** Create an expression node for an identifier with the name of zName
*/
Expr *sqlite3CreateIdExpr(const char *zName){
  Token dummy;
  setToken(&dummy, zName);
  return sqlite3Expr(TK_ID, 0, 0, &dummy);
}


/*
** Add a term to the WHERE expression in *ppExpr that requires the
** zCol column to be equal in the two tables pTab1 and pTab2.
*/
static void addWhereTerm(

  const char *zCol,        /* Name of the column */
  const Table *pTab1,      /* First table */
  const char *zAlias1,     /* Alias for first table.  May be NULL */
  const Table *pTab2,      /* Second table */
  const char *zAlias2,     /* Alias for second table.  May be NULL */
  int iRightJoinTable,     /* VDBE cursor for the right table */
  Expr **ppExpr            /* Add the equality term to this expression */
){
  Expr *pE1a, *pE1b, *pE1c;
  Expr *pE2a, *pE2b, *pE2c;
  Expr *pE;

  pE1a = sqlite3CreateIdExpr(zCol);
  pE2a = sqlite3CreateIdExpr(zCol);
  if( zAlias1==0 ){
    zAlias1 = pTab1->zName;
  }
  pE1b = sqlite3CreateIdExpr(zAlias1);
  if( zAlias2==0 ){
    zAlias2 = pTab2->zName;
  }
  pE2b = sqlite3CreateIdExpr(zAlias2);
  pE1c = sqlite3ExprOrFree(TK_DOT, pE1b, pE1a, 0);
  pE2c = sqlite3ExprOrFree(TK_DOT, pE2b, pE2a, 0);
  pE = sqlite3ExprOrFree(TK_EQ, pE1c, pE2c, 0);
  if( pE ){
    ExprSetProperty(pE, EP_FromJoin);
    pE->iRightJoinTable = iRightJoinTable;
  }
  pE = sqlite3ExprAnd(*ppExpr, pE);
  if( pE ){
    *ppExpr = pE;
  }
}

/*
** Set the EP_FromJoin property on all terms of the given expression.
................................................................................
    }

    /* Add the ON clause to the end of the WHERE clause, connected by
    ** an AND operator.
    */
    if( pRight->pOn ){
      setJoinExpr(pRight->pOn, pRight->iCursor);
      p->pWhere = sqlite3ExprAnd(p->pWhere, pRight->pOn);
      pRight->pOn = 0;
    }

    /* Create extra terms on the WHERE clause for each column named
    ** in the USING clause.  Example: If the two tables to be joined are 
    ** A and B and the USING clause names X, Y, and Z, then add this
    ** to the WHERE clause:    A.X=B.X AND A.Y=B.Y AND A.Z=B.Z
................................................................................
  sqlite3 *db = pParse->db;
  int nExpr;
  KeyInfo *pInfo;
  struct ExprList_item *pItem;
  int i;

  nExpr = pList->nExpr;
  pInfo = sqliteMalloc( sizeof(*pInfo) + nExpr*(sizeof(CollSeq*)+1) );
  if( pInfo ){
    pInfo->aSortOrder = (u8*)&pInfo->aColl[nExpr];
    pInfo->nField = nExpr;
    pInfo->enc = ENC(db);
    for(i=0, pItem=pList->a; i<nExpr; i++, pItem++){
      CollSeq *pColl;
      pColl = sqlite3ExprCollSeq(pParse, pItem->pExpr);
................................................................................
  /* If this is an EXPLAIN, skip this step */
  if( pParse->explain ){
    return;
  }
#endif

  assert( v!=0 );
  if( pParse->colNamesSet || v==0 || sqlite3MallocFailed() ) return;
  pParse->colNamesSet = 1;
  fullNames = (db->flags & SQLITE_FullColNames)!=0;
  shortNames = (db->flags & SQLITE_ShortColNames)!=0;
  sqlite3VdbeSetNumCols(v, pEList->nExpr);
  for(i=0; i<pEList->nExpr; i++){
    Expr *p;
    p = pEList->a[i].pExpr;
................................................................................
** the result set of that SELECT.
*/
Table *sqlite3ResultSetOfSelect(Parse *pParse, char *zTabName, Select *pSelect){
  Table *pTab;
  int i, j;
  ExprList *pEList;
  Column *aCol, *pCol;


  while( pSelect->pPrior ) pSelect = pSelect->pPrior;
  if( prepSelectStmt(pParse, pSelect) ){
    return 0;
  }
  if( sqlite3SelectResolve(pParse, pSelect, 0) ){
    return 0;
  }
  pTab = sqliteMalloc( sizeof(Table) );
  if( pTab==0 ){
    return 0;
  }
  pTab->nRef = 1;
  pTab->zName = zTabName ? sqliteStrDup(zTabName) : 0;
  pEList = pSelect->pEList;
  pTab->nCol = pEList->nExpr;
  assert( pTab->nCol>0 );
  pTab->aCol = aCol = sqliteMalloc( sizeof(pTab->aCol[0])*pTab->nCol );
  for(i=0, pCol=aCol; i<pTab->nCol; i++, pCol++){
    Expr *p, *pR;
    char *zType;
    char *zName;
    int nName;
    CollSeq *pColl;
    int cnt;
................................................................................
    
    /* Get an appropriate name for the column
    */
    p = pEList->a[i].pExpr;
    assert( p->pRight==0 || p->pRight->token.z==0 || p->pRight->token.z[0]!=0 );
    if( (zName = pEList->a[i].zName)!=0 ){
      /* If the column contains an "AS <name>" phrase, use <name> as the name */
      zName = sqliteStrDup(zName);
    }else if( p->op==TK_DOT 
              && (pR=p->pRight)!=0 && pR->token.z && pR->token.z[0] ){
      /* For columns of the from A.B use B as the name */
      zName = sqlite3MPrintf("%T", &pR->token);
    }else if( p->span.z && p->span.z[0] ){
      /* Use the original text of the column expression as its name */
      zName = sqlite3MPrintf("%T", &p->span);
    }else{
      /* If all else fails, make up a name */
      zName = sqlite3MPrintf("column%d", i+1);
    }
    sqlite3Dequote(zName);
    if( sqlite3MallocFailed() ){
      sqliteFree(zName);
      sqlite3DeleteTable(pTab);
      return 0;
    }

    /* Make sure the column name is unique.  If the name is not unique,
    ** append a integer to the name so that it becomes unique.
    */
................................................................................
    pCol->zName = zName;

    /* Get the typename, type affinity, and collating sequence for the
    ** column.
    */
    memset(&sNC, 0, sizeof(sNC));
    sNC.pSrcList = pSelect->pSrc;
    zType = sqliteStrDup(columnType(&sNC, p, 0, 0, 0));
    pCol->zType = zType;
    pCol->affinity = sqlite3ExprAffinity(p);
    pColl = sqlite3ExprCollSeq(pParse, p);
    if( pColl ){
      pCol->zColl = sqliteStrDup(pColl->zName);
    }
  }
  pTab->iPKey = -1;
  return pTab;
}

/*
................................................................................
** in pParse and return non-zero.
*/
static int prepSelectStmt(Parse *pParse, Select *p){
  int i, j, k, rc;
  SrcList *pTabList;
  ExprList *pEList;
  struct SrcList_item *pFrom;


  if( p==0 || p->pSrc==0 || sqlite3MallocFailed() ){
    return 1;
  }
  pTabList = p->pSrc;
  pEList = p->pEList;

  /* Make sure cursor numbers have been assigned to all entries in
  ** the FROM clause of the SELECT statement.
................................................................................
        }
        /* If pFrom->pSelect!=0 it means we are dealing with a
        ** view within a view.  The SELECT structure has already been
        ** copied by the outer view so we can skip the copy step here
        ** in the inner view.
        */
        if( pFrom->pSelect==0 ){
          pFrom->pSelect = sqlite3SelectDup(pTab->pSelect);
        }
      }
#endif
    }
  }

  /* Process NATURAL keywords, and ON and USING clauses of joins.
................................................................................

    for(k=0; k<pEList->nExpr; k++){
      Expr *pE = a[k].pExpr;
      if( pE->op!=TK_ALL &&
           (pE->op!=TK_DOT || pE->pRight==0 || pE->pRight->op!=TK_ALL) ){
        /* This particular expression does not need to be expanded.
        */
        pNew = sqlite3ExprListAppend(pNew, a[k].pExpr, 0);
        if( pNew ){
          pNew->a[pNew->nExpr-1].zName = a[k].zName;
        }else{
          rc = 1;
        }
        a[k].pExpr = 0;
        a[k].zName = 0;
      }else{
        /* This expression is a "*" or a "TABLE.*" and needs to be
        ** expanded. */
        int tableSeen = 0;      /* Set to 1 when TABLE matches */
        char *zTName;            /* text of name of TABLE */
        if( pE->op==TK_DOT && pE->pLeft ){
          zTName = sqlite3NameFromToken(&pE->pLeft->token);
        }else{
          zTName = 0;
        }
        for(i=0, pFrom=pTabList->a; i<pTabList->nSrc; i++, pFrom++){
          Table *pTab = pFrom->pTab;
          char *zTabName = pFrom->zAlias;
          if( zTabName==0 || zTabName[0]==0 ){ 
................................................................................
              pExpr->token.dyn = 0;
            }else{
              pExpr = pRight;
              pExpr->span = pExpr->token;
              pExpr->span.dyn = 0;
            }
            if( longNames ){
              pNew = sqlite3ExprListAppend(pNew, pExpr, &pExpr->span);
            }else{
              pNew = sqlite3ExprListAppend(pNew, pExpr, &pRight->token);
            }
          }
        }
        if( !tableSeen ){
          if( zTName ){
            sqlite3ErrorMsg(pParse, "no such table: %s", zTName);
          }else{
            sqlite3ErrorMsg(pParse, "no tables specified");
          }
          rc = 1;
        }
        sqliteFree(zTName);
      }
    }
    sqlite3ExprListDelete(pEList);
    p->pEList = pNew;
  }
  if( p->pEList && p->pEList->nExpr>SQLITE_MAX_COLUMN ){
    sqlite3ErrorMsg(pParse, "too many columns in result set");
    rc = SQLITE_ERROR;
  }
  if( sqlite3MallocFailed() ){
    rc = SQLITE_NOMEM;
  }
  return rc;
}

#ifndef SQLITE_OMIT_COMPOUND_SELECT
/*
................................................................................
  ExprList *pOrderBy,     /* The ORDER BY values to match against columns */
  int iTable,             /* Insert this value in iTable */
  int mustComplete        /* If TRUE all ORDER BYs must match */
){
  int nErr = 0;
  int i, j;
  ExprList *pEList;


  if( pSelect==0 || pOrderBy==0 ) return 1;
  if( mustComplete ){
    for(i=0; i<pOrderBy->nExpr; i++){ pOrderBy->a[i].done = 0; }
  }
  if( prepSelectStmt(pParse, pSelect) ){
    return 1;
................................................................................
          iCol, pEList->nExpr);
        nErr++;
        break;
      }
      if( !mustComplete ) continue;
      iCol--;
    }
    if( iCol<0 && (zLabel = sqlite3NameFromToken(&pE->token))!=0 ){
      for(j=0, pItem=pEList->a; j<pEList->nExpr; j++, pItem++){
        char *zName;
        int isMatch;
        if( pItem->zName ){
          zName = sqlite3StrDup(pItem->zName);
        }else{
          zName = sqlite3NameFromToken(&pItem->pExpr->token);
        }
        isMatch = zName && sqlite3StrICmp(zName, zLabel)==0;
        sqliteFree(zName);
        if( isMatch ){
          iCol = j;
          break;
        }
      }
      sqliteFree(zLabel);
    }
    if( iCol>=0 ){
      pE->op = TK_COLUMN;
      pE->iColumn = iCol;
      pE->iTable = iTable;
      pE->iAgg = -1;
      pOrderBy->a[i].done = 1;
................................................................................
    Select *pLoop;                /* For looping through SELECT statements */
    int nKeyCol;                  /* Number of entries in pKeyInfo->aCol[] */
    CollSeq **apColl;             /* For looping through pKeyInfo->aColl[] */
    CollSeq **aCopy;              /* A copy of pKeyInfo->aColl[] */

    assert( p->pRightmost==p );
    nKeyCol = nCol + (pOrderBy ? pOrderBy->nExpr : 0);

    pKeyInfo = sqliteMalloc(sizeof(*pKeyInfo)+nKeyCol*(sizeof(CollSeq*) + 1));
    if( !pKeyInfo ){
      rc = SQLITE_NOMEM;
      goto multi_select_end;
    }

    pKeyInfo->enc = ENC(pParse->db);
    pKeyInfo->nField = nCol;
................................................................................
      sqlite3VdbeChangeP2(v, addr, p->pOrderBy->nExpr+2);
      pKeyInfo->nField = nOrderByExpr;
      sqlite3VdbeChangeP3(v, addr, (char*)pKeyInfo, P3_KEYINFO_HANDOFF);
      pKeyInfo = 0;
      generateSortTail(pParse, p, v, p->pEList->nExpr, eDest, iParm);
    }

    sqliteFree(pKeyInfo);
  }

multi_select_end:
  return rc;
}
#endif /* SQLITE_OMIT_COMPOUND_SELECT */

#ifndef SQLITE_OMIT_VIEW




/*
** Scan through the expression pExpr.  Replace every reference to
** a column in table number iTable with a copy of the iColumn-th
** entry in pEList.  (But leave references to the ROWID column 
** unchanged.)
**
** This routine is part of the flattening procedure.  A subquery
** whose result set is defined by pEList appears as entry in the
** FROM clause of a SELECT such that the VDBE cursor assigned to that
** FORM clause entry is iTable.  This routine make the necessary 
** changes to pExpr so that it refers directly to the source table
** of the subquery rather the result set of the subquery.
*/
static void substExprList(ExprList*,int,ExprList*);  /* Forward Decl */
static void substSelect(Select *, int, ExprList *);  /* Forward Decl */
static void substExpr(Expr *pExpr, int iTable, ExprList *pEList){



  if( pExpr==0 ) return;
  if( pExpr->op==TK_COLUMN && pExpr->iTable==iTable ){
    if( pExpr->iColumn<0 ){
      pExpr->op = TK_NULL;
    }else{
      Expr *pNew;
      assert( pEList!=0 && pExpr->iColumn<pEList->nExpr );
      assert( pExpr->pLeft==0 && pExpr->pRight==0 && pExpr->pList==0 );
      pNew = pEList->a[pExpr->iColumn].pExpr;
      assert( pNew!=0 );
      pExpr->op = pNew->op;
      assert( pExpr->pLeft==0 );
      pExpr->pLeft = sqlite3ExprDup(pNew->pLeft);
      assert( pExpr->pRight==0 );
      pExpr->pRight = sqlite3ExprDup(pNew->pRight);
      assert( pExpr->pList==0 );
      pExpr->pList = sqlite3ExprListDup(pNew->pList);
      pExpr->iTable = pNew->iTable;
      pExpr->pTab = pNew->pTab;
      pExpr->iColumn = pNew->iColumn;
      pExpr->iAgg = pNew->iAgg;
      sqlite3TokenCopy(&pExpr->token, &pNew->token);
      sqlite3TokenCopy(&pExpr->span, &pNew->span);
      pExpr->pSelect = sqlite3SelectDup(pNew->pSelect);
      pExpr->flags = pNew->flags;
    }
  }else{
    substExpr(pExpr->pLeft, iTable, pEList);
    substExpr(pExpr->pRight, iTable, pEList);
    substSelect(pExpr->pSelect, iTable, pEList);
    substExprList(pExpr->pList, iTable, pEList);
  }
}
static void substExprList(ExprList *pList, int iTable, ExprList *pEList){





  int i;
  if( pList==0 ) return;
  for(i=0; i<pList->nExpr; i++){
    substExpr(pList->a[i].pExpr, iTable, pEList);
  }
}
static void substSelect(Select *p, int iTable, ExprList *pEList){





  if( !p ) return;
  substExprList(p->pEList, iTable, pEList);
  substExprList(p->pGroupBy, iTable, pEList);
  substExprList(p->pOrderBy, iTable, pEList);
  substExpr(p->pHaving, iTable, pEList);
  substExpr(p->pWhere, iTable, pEList);
  substSelect(p->pPrior, iTable, pEList);
}
#endif /* !defined(SQLITE_OMIT_VIEW) */

#ifndef SQLITE_OMIT_VIEW
/*
** This routine attempts to flatten subqueries in order to speed
** execution.  It returns 1 if it makes changes and 0 if no flattening
................................................................................
** If flattening is not attempted, this routine is a no-op and returns 0.
** If flattening is attempted this routine returns 1.
**
** All of the expression analysis must occur on both the outer query and
** the subquery before this routine runs.
*/
static int flattenSubquery(

  Select *p,           /* The parent or outer SELECT statement */
  int iFrom,           /* Index in p->pSrc->a[] of the inner subquery */
  int isAgg,           /* True if outer SELECT uses aggregate functions */
  int subqueryIsAgg    /* True if the subquery uses aggregate functions */
){
  Select *pSub;       /* The inner query or "subquery" */
  SrcList *pSrc;      /* The FROM clause of the outer query */
................................................................................
  */
  iParent = pSubitem->iCursor;
  {
    int nSubSrc = pSubSrc->nSrc;
    int jointype = pSubitem->jointype;

    sqlite3DeleteTable(pSubitem->pTab);
    sqliteFree(pSubitem->zDatabase);
    sqliteFree(pSubitem->zName);
    sqliteFree(pSubitem->zAlias);
    if( nSubSrc>1 ){
      int extra = nSubSrc - 1;
      for(i=1; i<nSubSrc; i++){
        pSrc = sqlite3SrcListAppend(pSrc, 0, 0);
      }
      p->pSrc = pSrc;
      for(i=pSrc->nSrc-1; i-extra>=iFrom; i--){
        pSrc->a[i] = pSrc->a[i-extra];
      }
    }
    for(i=0; i<nSubSrc; i++){
................................................................................
  ** We look at every expression in the outer query and every place we see
  ** "a" we substitute "x*3" and every place we see "b" we substitute "y+10".
  */
  pList = p->pEList;
  for(i=0; i<pList->nExpr; i++){
    Expr *pExpr;
    if( pList->a[i].zName==0 && (pExpr = pList->a[i].pExpr)->span.z!=0 ){

      pList->a[i].zName = sqliteStrNDup((char*)pExpr->span.z, pExpr->span.n);
    }
  }
  substExprList(p->pEList, iParent, pSub->pEList);
  if( isAgg ){
    substExprList(p->pGroupBy, iParent, pSub->pEList);
    substExpr(p->pHaving, iParent, pSub->pEList);
  }
................................................................................
    assert( p->pOrderBy==0 );
    p->pOrderBy = pSub->pOrderBy;
    pSub->pOrderBy = 0;
  }else if( p->pOrderBy ){
    substExprList(p->pOrderBy, iParent, pSub->pEList);
  }
  if( pSub->pWhere ){
    pWhere = sqlite3ExprDup(pSub->pWhere);
  }else{
    pWhere = 0;
  }
  if( subqueryIsAgg ){
    assert( p->pHaving==0 );
    p->pHaving = p->pWhere;
    p->pWhere = pWhere;
    substExpr(p->pHaving, iParent, pSub->pEList);
    p->pHaving = sqlite3ExprAnd(p->pHaving, sqlite3ExprDup(pSub->pHaving));

    assert( p->pGroupBy==0 );
    p->pGroupBy = sqlite3ExprListDup(pSub->pGroupBy);
  }else{
    substExpr(p->pWhere, iParent, pSub->pEList);
    p->pWhere = sqlite3ExprAnd(p->pWhere, pWhere);
  }

  /* The flattened query is distinct if either the inner or the
  ** outer query is distinct. 
  */
  p->isDistinct = p->isDistinct || pSub->isDistinct;

................................................................................
    int iCol;
    Expr *pE = pOrderBy->a[i].pExpr;
    if( sqlite3ExprIsInteger(pE, &iCol) ){
      if( iCol>0 && iCol<=pEList->nExpr ){
        CollSeq *pColl = pE->pColl;
        int flags = pE->flags & EP_ExpCollate;
        sqlite3ExprDelete(pE);

        pE = pOrderBy->a[i].pExpr = sqlite3ExprDup(pEList->a[iCol-1].pExpr);
        if( pColl && flags ){
          pE->pColl = pColl;
          pE->flags |= flags;
        }
      }else{
        sqlite3ErrorMsg(pParse, 
           "%s BY column number %d out of range - should be "
................................................................................
  if( p->pPrior==0 ){
    if( processOrderGroupBy(&sNC, p->pOrderBy, "ORDER") ||
        processOrderGroupBy(&sNC, pGroupBy, "GROUP") ){
      return SQLITE_ERROR;
    }
  }

  if( sqlite3MallocFailed() ){
    return SQLITE_NOMEM;
  }

  /* Make sure the GROUP BY clause does not contain aggregate functions.
  */
  if( pGroupBy ){
    struct ExprList_item *pItem;
................................................................................
  Expr *pHaving;         /* The HAVING clause.  May be NULL */
  int isDistinct;        /* True if the DISTINCT keyword is present */
  int distinct;          /* Table to use for the distinct set */
  int rc = 1;            /* Value to return from this function */
  int addrSortIndex;     /* Address of an OP_OpenEphemeral instruction */
  AggInfo sAggInfo;      /* Information used by aggregate queries */
  int iEnd;              /* Address of the end of the query */


  if( p==0 || sqlite3MallocFailed() || pParse->nErr ){


    return 1;
  }
  if( sqlite3AuthCheck(pParse, SQLITE_SELECT, 0, 0, 0) ) return 1;
  memset(&sAggInfo, 0, sizeof(sAggInfo));

#ifndef SQLITE_OMIT_COMPOUND_SELECT
  /* If there is are a sequence of queries, do the earlier ones first.
................................................................................
  }

  /* Check to see if this is a subquery that can be "flattened" into its parent.
  ** If flattening is a possiblity, do so and return immediately.  
  */
#ifndef SQLITE_OMIT_VIEW
  if( pParent && pParentAgg &&
      flattenSubquery(pParent, parentTab, *pParentAgg, isAgg) ){
    if( isAgg ) *pParentAgg = 1;
    goto select_end;
  }
#endif

  /* If there is an ORDER BY clause, then this sorting
  ** index might end up being unused if the data can be 
................................................................................
    }
    sAggInfo.nAccumulator = sAggInfo.nColumn;
    for(i=0; i<sAggInfo.nFunc; i++){
      if( sqlite3ExprAnalyzeAggList(&sNC, sAggInfo.aFunc[i].pExpr->pList) ){
        goto select_end;
      }
    }
    if( sqlite3MallocFailed() ) goto select_end;

    /* Processing for aggregates with GROUP BY is very different and
    ** much more complex tha aggregates without a GROUP BY.
    */
    if( pGroupBy ){
      KeyInfo *pKeyInfo;  /* Keying information for the group by clause */

................................................................................
  /* Identify column names if we will be using them in a callback.  This
  ** step is skipped if the output is going to some other destination.
  */
  if( rc==SQLITE_OK && eDest==SRT_Callback ){
    generateColumnNames(pParse, pTabList, pEList);
  }

  sqliteFree(sAggInfo.aCol);
  sqliteFree(sAggInfo.aFunc);
  return rc;
}

#if defined(SQLITE_DEBUG)
/*
*******************************************************************************
** The following code is used for testing and debugging only.  The code

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains C code routines that are called by the parser
** to handle SELECT statements in SQLite.
**
** $Id: select.c,v 1.355 2007/08/16 04:30:40 drh Exp $
*/
#include "sqliteInt.h"


/*
** Delete all the content of a Select structure but do not deallocate
** the select structure itself.
................................................................................


/*
** Allocate a new Select structure and return a pointer to that
** structure.
*/
Select *sqlite3SelectNew(
  Parse *pParse,        /* Parsing context */
  ExprList *pEList,     /* which columns to include in the result */
  SrcList *pSrc,        /* the FROM clause -- which tables to scan */
  Expr *pWhere,         /* the WHERE clause */
  ExprList *pGroupBy,   /* the GROUP BY clause */
  Expr *pHaving,        /* the HAVING clause */
  ExprList *pOrderBy,   /* the ORDER BY clause */
  int isDistinct,       /* true if the DISTINCT keyword is present */
  Expr *pLimit,         /* LIMIT value.  NULL means not used */
  Expr *pOffset         /* OFFSET value.  NULL means no offset */
){
  Select *pNew;
  Select standin;
  sqlite3 *db = pParse->db;
  pNew = sqlite3DbMallocZero(db, sizeof(*pNew) );
  assert( !pOffset || pLimit );   /* Can't have OFFSET without LIMIT. */
  if( pNew==0 ){
    pNew = &standin;
    memset(pNew, 0, sizeof(*pNew));
  }
  if( pEList==0 ){
    pEList = sqlite3ExprListAppend(pParse, 0, sqlite3Expr(TK_ALL,0,0,0), 0);
  }
  pNew->pEList = pEList;
  pNew->pSrc = pSrc;
  pNew->pWhere = pWhere;
  pNew->pGroupBy = pGroupBy;
  pNew->pHaving = pHaving;
  pNew->pOrderBy = pOrderBy;
................................................................................

/*
** Delete the given Select structure and all of its substructures.
*/
void sqlite3SelectDelete(Select *p){
  if( p ){
    clearSelect(p);
    sqlite3_free(p);
  }
}

/*
** Given 1 to 3 identifiers preceeding the JOIN keyword, determine the
** type of join.  Return an integer constant that expresses that type
** in terms of the following bit values:
................................................................................
    p->n = strlen((char *)p->z);
  }
}

/*
** Create an expression node for an identifier with the name of zName
*/
Expr *sqlite3CreateIdExpr(Parse *pParse, const char *zName){
  Token dummy;
  setToken(&dummy, zName);
  return sqlite3PExpr(pParse, TK_ID, 0, 0, &dummy);
}


/*
** Add a term to the WHERE expression in *ppExpr that requires the
** zCol column to be equal in the two tables pTab1 and pTab2.
*/
static void addWhereTerm(
  Parse *pParse,           /* Parsing context */
  const char *zCol,        /* Name of the column */
  const Table *pTab1,      /* First table */
  const char *zAlias1,     /* Alias for first table.  May be NULL */
  const Table *pTab2,      /* Second table */
  const char *zAlias2,     /* Alias for second table.  May be NULL */
  int iRightJoinTable,     /* VDBE cursor for the right table */
  Expr **ppExpr            /* Add the equality term to this expression */
){
  Expr *pE1a, *pE1b, *pE1c;
  Expr *pE2a, *pE2b, *pE2c;
  Expr *pE;

  pE1a = sqlite3CreateIdExpr(pParse, zCol);
  pE2a = sqlite3CreateIdExpr(pParse, zCol);
  if( zAlias1==0 ){
    zAlias1 = pTab1->zName;
  }
  pE1b = sqlite3CreateIdExpr(pParse, zAlias1);
  if( zAlias2==0 ){
    zAlias2 = pTab2->zName;
  }
  pE2b = sqlite3CreateIdExpr(pParse, zAlias2);
  pE1c = sqlite3PExpr(pParse, TK_DOT, pE1b, pE1a, 0);
  pE2c = sqlite3PExpr(pParse, TK_DOT, pE2b, pE2a, 0);
  pE = sqlite3DbExpr(pParse, TK_EQ, pE1c, pE2c, 0);
  if( pE ){
    ExprSetProperty(pE, EP_FromJoin);
    pE->iRightJoinTable = iRightJoinTable;
  }
  pE = sqlite3ExprAnd(pParse->db,*ppExpr, pE);
  if( pE ){
    *ppExpr = pE;
  }
}

/*
** Set the EP_FromJoin property on all terms of the given expression.
................................................................................
    }

    /* Add the ON clause to the end of the WHERE clause, connected by
    ** an AND operator.
    */
    if( pRight->pOn ){
      setJoinExpr(pRight->pOn, pRight->iCursor);
      p->pWhere = sqlite3ExprAnd(pParse->db, p->pWhere, pRight->pOn);
      pRight->pOn = 0;
    }

    /* Create extra terms on the WHERE clause for each column named
    ** in the USING clause.  Example: If the two tables to be joined are 
    ** A and B and the USING clause names X, Y, and Z, then add this
    ** to the WHERE clause:    A.X=B.X AND A.Y=B.Y AND A.Z=B.Z
................................................................................
  sqlite3 *db = pParse->db;
  int nExpr;
  KeyInfo *pInfo;
  struct ExprList_item *pItem;
  int i;

  nExpr = pList->nExpr;
  pInfo = sqlite3DbMallocZero(db, sizeof(*pInfo) + nExpr*(sizeof(CollSeq*)+1) );
  if( pInfo ){
    pInfo->aSortOrder = (u8*)&pInfo->aColl[nExpr];
    pInfo->nField = nExpr;
    pInfo->enc = ENC(db);
    for(i=0, pItem=pList->a; i<nExpr; i++, pItem++){
      CollSeq *pColl;
      pColl = sqlite3ExprCollSeq(pParse, pItem->pExpr);
................................................................................
  /* If this is an EXPLAIN, skip this step */
  if( pParse->explain ){
    return;
  }
#endif

  assert( v!=0 );
  if( pParse->colNamesSet || v==0 || db->mallocFailed ) return;
  pParse->colNamesSet = 1;
  fullNames = (db->flags & SQLITE_FullColNames)!=0;
  shortNames = (db->flags & SQLITE_ShortColNames)!=0;
  sqlite3VdbeSetNumCols(v, pEList->nExpr);
  for(i=0; i<pEList->nExpr; i++){
    Expr *p;
    p = pEList->a[i].pExpr;
................................................................................
** the result set of that SELECT.
*/
Table *sqlite3ResultSetOfSelect(Parse *pParse, char *zTabName, Select *pSelect){
  Table *pTab;
  int i, j;
  ExprList *pEList;
  Column *aCol, *pCol;
  sqlite3 *db = pParse->db;

  while( pSelect->pPrior ) pSelect = pSelect->pPrior;
  if( prepSelectStmt(pParse, pSelect) ){
    return 0;
  }
  if( sqlite3SelectResolve(pParse, pSelect, 0) ){
    return 0;
  }
  pTab = sqlite3DbMallocZero(db, sizeof(Table) );
  if( pTab==0 ){
    return 0;
  }
  pTab->nRef = 1;
  pTab->zName = zTabName ? sqlite3DbStrDup(db, zTabName) : 0;
  pEList = pSelect->pEList;
  pTab->nCol = pEList->nExpr;
  assert( pTab->nCol>0 );
  pTab->aCol = aCol = sqlite3DbMallocZero(db, sizeof(pTab->aCol[0])*pTab->nCol);
  for(i=0, pCol=aCol; i<pTab->nCol; i++, pCol++){
    Expr *p, *pR;
    char *zType;
    char *zName;
    int nName;
    CollSeq *pColl;
    int cnt;
................................................................................
    
    /* Get an appropriate name for the column
    */
    p = pEList->a[i].pExpr;
    assert( p->pRight==0 || p->pRight->token.z==0 || p->pRight->token.z[0]!=0 );
    if( (zName = pEList->a[i].zName)!=0 ){
      /* If the column contains an "AS <name>" phrase, use <name> as the name */
      zName = sqlite3DbStrDup(db, zName);
    }else if( p->op==TK_DOT 
              && (pR=p->pRight)!=0 && pR->token.z && pR->token.z[0] ){
      /* For columns of the from A.B use B as the name */
      zName = sqlite3MPrintf(db, "%T", &pR->token);
    }else if( p->span.z && p->span.z[0] ){
      /* Use the original text of the column expression as its name */
      zName = sqlite3MPrintf(db, "%T", &p->span);
    }else{
      /* If all else fails, make up a name */
      zName = sqlite3MPrintf(db, "column%d", i+1);
    }
    sqlite3Dequote(zName);
    if( db->mallocFailed ){
      sqlite3_free(zName);
      sqlite3DeleteTable(pTab);
      return 0;
    }

    /* Make sure the column name is unique.  If the name is not unique,
    ** append a integer to the name so that it becomes unique.
    */
................................................................................
    pCol->zName = zName;

    /* Get the typename, type affinity, and collating sequence for the
    ** column.
    */
    memset(&sNC, 0, sizeof(sNC));
    sNC.pSrcList = pSelect->pSrc;
    zType = sqlite3DbStrDup(db, columnType(&sNC, p, 0, 0, 0));
    pCol->zType = zType;
    pCol->affinity = sqlite3ExprAffinity(p);
    pColl = sqlite3ExprCollSeq(pParse, p);
    if( pColl ){
      pCol->zColl = sqlite3DbStrDup(db, pColl->zName);
    }
  }
  pTab->iPKey = -1;
  return pTab;
}

/*
................................................................................
** in pParse and return non-zero.
*/
static int prepSelectStmt(Parse *pParse, Select *p){
  int i, j, k, rc;
  SrcList *pTabList;
  ExprList *pEList;
  struct SrcList_item *pFrom;
  sqlite3 *db = pParse->db;

  if( p==0 || p->pSrc==0 || db->mallocFailed ){
    return 1;
  }
  pTabList = p->pSrc;
  pEList = p->pEList;

  /* Make sure cursor numbers have been assigned to all entries in
  ** the FROM clause of the SELECT statement.
................................................................................
        }
        /* If pFrom->pSelect!=0 it means we are dealing with a
        ** view within a view.  The SELECT structure has already been
        ** copied by the outer view so we can skip the copy step here
        ** in the inner view.
        */
        if( pFrom->pSelect==0 ){
          pFrom->pSelect = sqlite3SelectDup(db, pTab->pSelect);
        }
      }
#endif
    }
  }

  /* Process NATURAL keywords, and ON and USING clauses of joins.
................................................................................

    for(k=0; k<pEList->nExpr; k++){
      Expr *pE = a[k].pExpr;
      if( pE->op!=TK_ALL &&
           (pE->op!=TK_DOT || pE->pRight==0 || pE->pRight->op!=TK_ALL) ){
        /* This particular expression does not need to be expanded.
        */
        pNew = sqlite3ExprListAppend(pParse, pNew, a[k].pExpr, 0);
        if( pNew ){
          pNew->a[pNew->nExpr-1].zName = a[k].zName;
        }else{
          rc = 1;
        }
        a[k].pExpr = 0;
        a[k].zName = 0;
      }else{
        /* This expression is a "*" or a "TABLE.*" and needs to be
        ** expanded. */
        int tableSeen = 0;      /* Set to 1 when TABLE matches */
        char *zTName;            /* text of name of TABLE */
        if( pE->op==TK_DOT && pE->pLeft ){
          zTName = sqlite3NameFromToken(db, &pE->pLeft->token);
        }else{
          zTName = 0;
        }
        for(i=0, pFrom=pTabList->a; i<pTabList->nSrc; i++, pFrom++){
          Table *pTab = pFrom->pTab;
          char *zTabName = pFrom->zAlias;
          if( zTabName==0 || zTabName[0]==0 ){ 
................................................................................
              pExpr->token.dyn = 0;
            }else{
              pExpr = pRight;
              pExpr->span = pExpr->token;
              pExpr->span.dyn = 0;
            }
            if( longNames ){
              pNew = sqlite3ExprListAppend(pParse, pNew, pExpr, &pExpr->span);
            }else{
              pNew = sqlite3ExprListAppend(pParse, pNew, pExpr, &pRight->token);
            }
          }
        }
        if( !tableSeen ){
          if( zTName ){
            sqlite3ErrorMsg(pParse, "no such table: %s", zTName);
          }else{
            sqlite3ErrorMsg(pParse, "no tables specified");
          }
          rc = 1;
        }
        sqlite3_free(zTName);
      }
    }
    sqlite3ExprListDelete(pEList);
    p->pEList = pNew;
  }
  if( p->pEList && p->pEList->nExpr>SQLITE_MAX_COLUMN ){
    sqlite3ErrorMsg(pParse, "too many columns in result set");
    rc = SQLITE_ERROR;
  }
  if( db->mallocFailed ){
    rc = SQLITE_NOMEM;
  }
  return rc;
}

#ifndef SQLITE_OMIT_COMPOUND_SELECT
/*
................................................................................
  ExprList *pOrderBy,     /* The ORDER BY values to match against columns */
  int iTable,             /* Insert this value in iTable */
  int mustComplete        /* If TRUE all ORDER BYs must match */
){
  int nErr = 0;
  int i, j;
  ExprList *pEList;
  sqlite3 *db = pParse->db;

  if( pSelect==0 || pOrderBy==0 ) return 1;
  if( mustComplete ){
    for(i=0; i<pOrderBy->nExpr; i++){ pOrderBy->a[i].done = 0; }
  }
  if( prepSelectStmt(pParse, pSelect) ){
    return 1;
................................................................................
          iCol, pEList->nExpr);
        nErr++;
        break;
      }
      if( !mustComplete ) continue;
      iCol--;
    }
    if( iCol<0 && (zLabel = sqlite3NameFromToken(db, &pE->token))!=0 ){
      for(j=0, pItem=pEList->a; j<pEList->nExpr; j++, pItem++){
        char *zName;
        int isMatch;
        if( pItem->zName ){
          zName = sqlite3DbStrDup(db, pItem->zName);
        }else{
          zName = sqlite3NameFromToken(db, &pItem->pExpr->token);
        }
        isMatch = zName && sqlite3StrICmp(zName, zLabel)==0;
        sqlite3_free(zName);
        if( isMatch ){
          iCol = j;
          break;
        }
      }
      sqlite3_free(zLabel);
    }
    if( iCol>=0 ){
      pE->op = TK_COLUMN;
      pE->iColumn = iCol;
      pE->iTable = iTable;
      pE->iAgg = -1;
      pOrderBy->a[i].done = 1;
................................................................................
    Select *pLoop;                /* For looping through SELECT statements */
    int nKeyCol;                  /* Number of entries in pKeyInfo->aCol[] */
    CollSeq **apColl;             /* For looping through pKeyInfo->aColl[] */
    CollSeq **aCopy;              /* A copy of pKeyInfo->aColl[] */

    assert( p->pRightmost==p );
    nKeyCol = nCol + (pOrderBy ? pOrderBy->nExpr : 0);
    pKeyInfo = sqlite3DbMallocZero(pParse->db,
                       sizeof(*pKeyInfo)+nKeyCol*(sizeof(CollSeq*) + 1));
    if( !pKeyInfo ){
      rc = SQLITE_NOMEM;
      goto multi_select_end;
    }

    pKeyInfo->enc = ENC(pParse->db);
    pKeyInfo->nField = nCol;
................................................................................
      sqlite3VdbeChangeP2(v, addr, p->pOrderBy->nExpr+2);
      pKeyInfo->nField = nOrderByExpr;
      sqlite3VdbeChangeP3(v, addr, (char*)pKeyInfo, P3_KEYINFO_HANDOFF);
      pKeyInfo = 0;
      generateSortTail(pParse, p, v, p->pEList->nExpr, eDest, iParm);
    }

    sqlite3_free(pKeyInfo);
  }

multi_select_end:
  return rc;
}
#endif /* SQLITE_OMIT_COMPOUND_SELECT */

#ifndef SQLITE_OMIT_VIEW
/* Forward Declarations */
static void substExprList(sqlite3*, ExprList*, int, ExprList*);
static void substSelect(sqlite3*, Select *, int, ExprList *);

/*
** Scan through the expression pExpr.  Replace every reference to
** a column in table number iTable with a copy of the iColumn-th
** entry in pEList.  (But leave references to the ROWID column 
** unchanged.)
**
** This routine is part of the flattening procedure.  A subquery
** whose result set is defined by pEList appears as entry in the
** FROM clause of a SELECT such that the VDBE cursor assigned to that
** FORM clause entry is iTable.  This routine make the necessary 
** changes to pExpr so that it refers directly to the source table
** of the subquery rather the result set of the subquery.
*/
static void substExpr(
  sqlite3 *db,        /* Report malloc errors to this connection */
  Expr *pExpr,        /* Expr in which substitution occurs */
  int iTable,         /* Table to be substituted */
  ExprList *pEList    /* Substitute expressions */
){
  if( pExpr==0 ) return;
  if( pExpr->op==TK_COLUMN && pExpr->iTable==iTable ){
    if( pExpr->iColumn<0 ){
      pExpr->op = TK_NULL;
    }else{
      Expr *pNew;
      assert( pEList!=0 && pExpr->iColumn<pEList->nExpr );
      assert( pExpr->pLeft==0 && pExpr->pRight==0 && pExpr->pList==0 );
      pNew = pEList->a[pExpr->iColumn].pExpr;
      assert( pNew!=0 );
      pExpr->op = pNew->op;
      assert( pExpr->pLeft==0 );
      pExpr->pLeft = sqlite3ExprDup(db, pNew->pLeft);
      assert( pExpr->pRight==0 );
      pExpr->pRight = sqlite3ExprDup(db, pNew->pRight);
      assert( pExpr->pList==0 );
      pExpr->pList = sqlite3ExprListDup(db, pNew->pList);
      pExpr->iTable = pNew->iTable;
      pExpr->pTab = pNew->pTab;
      pExpr->iColumn = pNew->iColumn;
      pExpr->iAgg = pNew->iAgg;
      sqlite3TokenCopy(db, &pExpr->token, &pNew->token);
      sqlite3TokenCopy(db, &pExpr->span, &pNew->span);
      pExpr->pSelect = sqlite3SelectDup(db, pNew->pSelect);
      pExpr->flags = pNew->flags;
    }
  }else{
    substExpr(db, pExpr->pLeft, iTable, pEList);
    substExpr(db, pExpr->pRight, iTable, pEList);
    substSelect(db, pExpr->pSelect, iTable, pEList);
    substExprList(db, pExpr->pList, iTable, pEList);
  }
}
static void substExprList(
  sqlite3 *db,         /* Report malloc errors here */
  ExprList *pList,     /* List to scan and in which to make substitutes */
  int iTable,          /* Table to be substituted */
  ExprList *pEList     /* Substitute values */
){
  int i;
  if( pList==0 ) return;
  for(i=0; i<pList->nExpr; i++){
    substExpr(db, pList->a[i].pExpr, iTable, pEList);
  }
}
static void substSelect(
  sqlite3 *db,         /* Report malloc errors here */
  Select *p,           /* SELECT statement in which to make substitutions */
  int iTable,          /* Table to be replaced */
  ExprList *pEList     /* Substitute values */
){
  if( !p ) return;
  substExprList(db, p->pEList, iTable, pEList);
  substExprList(db, p->pGroupBy, iTable, pEList);
  substExprList(db, p->pOrderBy, iTable, pEList);
  substExpr(db, p->pHaving, iTable, pEList);
  substExpr(db, p->pWhere, iTable, pEList);
  substSelect(db, p->pPrior, iTable, pEList);
}
#endif /* !defined(SQLITE_OMIT_VIEW) */

#ifndef SQLITE_OMIT_VIEW
/*
** This routine attempts to flatten subqueries in order to speed
** execution.  It returns 1 if it makes changes and 0 if no flattening
................................................................................
** If flattening is not attempted, this routine is a no-op and returns 0.
** If flattening is attempted this routine returns 1.
**
** All of the expression analysis must occur on both the outer query and
** the subquery before this routine runs.
*/
static int flattenSubquery(
  sqlite3 *db,         /* Database connection */
  Select *p,           /* The parent or outer SELECT statement */
  int iFrom,           /* Index in p->pSrc->a[] of the inner subquery */
  int isAgg,           /* True if outer SELECT uses aggregate functions */
  int subqueryIsAgg    /* True if the subquery uses aggregate functions */
){
  Select *pSub;       /* The inner query or "subquery" */
  SrcList *pSrc;      /* The FROM clause of the outer query */
................................................................................
  */
  iParent = pSubitem->iCursor;
  {
    int nSubSrc = pSubSrc->nSrc;
    int jointype = pSubitem->jointype;

    sqlite3DeleteTable(pSubitem->pTab);
    sqlite3_free(pSubitem->zDatabase);
    sqlite3_free(pSubitem->zName);
    sqlite3_free(pSubitem->zAlias);
    if( nSubSrc>1 ){
      int extra = nSubSrc - 1;
      for(i=1; i<nSubSrc; i++){
        pSrc = sqlite3SrcListAppend(db, pSrc, 0, 0);
      }
      p->pSrc = pSrc;
      for(i=pSrc->nSrc-1; i-extra>=iFrom; i--){
        pSrc->a[i] = pSrc->a[i-extra];
      }
    }
    for(i=0; i<nSubSrc; i++){
................................................................................
  ** We look at every expression in the outer query and every place we see
  ** "a" we substitute "x*3" and every place we see "b" we substitute "y+10".
  */
  pList = p->pEList;
  for(i=0; i<pList->nExpr; i++){
    Expr *pExpr;
    if( pList->a[i].zName==0 && (pExpr = pList->a[i].pExpr)->span.z!=0 ){
      pList->a[i].zName = 
             sqlite3DbStrNDup(db, (char*)pExpr->span.z, pExpr->span.n);
    }
  }
  substExprList(p->pEList, iParent, pSub->pEList);
  if( isAgg ){
    substExprList(p->pGroupBy, iParent, pSub->pEList);
    substExpr(p->pHaving, iParent, pSub->pEList);
  }
................................................................................
    assert( p->pOrderBy==0 );
    p->pOrderBy = pSub->pOrderBy;
    pSub->pOrderBy = 0;
  }else if( p->pOrderBy ){
    substExprList(p->pOrderBy, iParent, pSub->pEList);
  }
  if( pSub->pWhere ){
    pWhere = sqlite3ExprDup(db, pSub->pWhere);
  }else{
    pWhere = 0;
  }
  if( subqueryIsAgg ){
    assert( p->pHaving==0 );
    p->pHaving = p->pWhere;
    p->pWhere = pWhere;
    substExpr(p->pHaving, iParent, pSub->pEList);
    p->pHaving = sqlite3ExprAnd(db, p->pHaving, 
                                sqlite3ExprDup(db, pSub->pHaving));
    assert( p->pGroupBy==0 );
    p->pGroupBy = sqlite3ExprListDup(db, pSub->pGroupBy);
  }else{
    substExpr(p->pWhere, iParent, pSub->pEList);
    p->pWhere = sqlite3ExprAnd(db, p->pWhere, pWhere);
  }

  /* The flattened query is distinct if either the inner or the
  ** outer query is distinct. 
  */
  p->isDistinct = p->isDistinct || pSub->isDistinct;

................................................................................
    int iCol;
    Expr *pE = pOrderBy->a[i].pExpr;
    if( sqlite3ExprIsInteger(pE, &iCol) ){
      if( iCol>0 && iCol<=pEList->nExpr ){
        CollSeq *pColl = pE->pColl;
        int flags = pE->flags & EP_ExpCollate;
        sqlite3ExprDelete(pE);
        pE = sqlite3ExprDup(pParse->db, pEList->a[iCol-1].pExpr);
        pOrderBy->a[i].pExpr = pE;
        if( pColl && flags ){
          pE->pColl = pColl;
          pE->flags |= flags;
        }
      }else{
        sqlite3ErrorMsg(pParse, 
           "%s BY column number %d out of range - should be "
................................................................................
  if( p->pPrior==0 ){
    if( processOrderGroupBy(&sNC, p->pOrderBy, "ORDER") ||
        processOrderGroupBy(&sNC, pGroupBy, "GROUP") ){
      return SQLITE_ERROR;
    }
  }

  if( db->mallocFailed ){
    return SQLITE_NOMEM;
  }

  /* Make sure the GROUP BY clause does not contain aggregate functions.
  */
  if( pGroupBy ){
    struct ExprList_item *pItem;
................................................................................
  Expr *pHaving;         /* The HAVING clause.  May be NULL */
  int isDistinct;        /* True if the DISTINCT keyword is present */
  int distinct;          /* Table to use for the distinct set */
  int rc = 1;            /* Value to return from this function */
  int addrSortIndex;     /* Address of an OP_OpenEphemeral instruction */
  AggInfo sAggInfo;      /* Information used by aggregate queries */
  int iEnd;              /* Address of the end of the query */
  sqlite3 *db;           /* The database connection */


  db = pParse->db;
  if( p==0 || db->mallocFailed || pParse->nErr ){
    return 1;
  }
  if( sqlite3AuthCheck(pParse, SQLITE_SELECT, 0, 0, 0) ) return 1;
  memset(&sAggInfo, 0, sizeof(sAggInfo));

#ifndef SQLITE_OMIT_COMPOUND_SELECT
  /* If there is are a sequence of queries, do the earlier ones first.
................................................................................
  }

  /* Check to see if this is a subquery that can be "flattened" into its parent.
  ** If flattening is a possiblity, do so and return immediately.  
  */
#ifndef SQLITE_OMIT_VIEW
  if( pParent && pParentAgg &&
      flattenSubquery(db, pParent, parentTab, *pParentAgg, isAgg) ){
    if( isAgg ) *pParentAgg = 1;
    goto select_end;
  }
#endif

  /* If there is an ORDER BY clause, then this sorting
  ** index might end up being unused if the data can be 
................................................................................
    }
    sAggInfo.nAccumulator = sAggInfo.nColumn;
    for(i=0; i<sAggInfo.nFunc; i++){
      if( sqlite3ExprAnalyzeAggList(&sNC, sAggInfo.aFunc[i].pExpr->pList) ){
        goto select_end;
      }
    }
    if( db->mallocFailed ) goto select_end;

    /* Processing for aggregates with GROUP BY is very different and
    ** much more complex tha aggregates without a GROUP BY.
    */
    if( pGroupBy ){
      KeyInfo *pKeyInfo;  /* Keying information for the group by clause */

................................................................................
  /* Identify column names if we will be using them in a callback.  This
  ** step is skipped if the output is going to some other destination.
  */
  if( rc==SQLITE_OK && eDest==SRT_Callback ){
    generateColumnNames(pParse, pTabList, pEList);
  }

  sqlite3_free(sAggInfo.aCol);
  sqlite3_free(sAggInfo.aFunc);
  return rc;
}

#if defined(SQLITE_DEBUG)
/*
*******************************************************************************
** The following code is used for testing and debugging only.  The code

**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** Internal interface definitions for SQLite.
**
** @(#) $Id: sqliteInt.h,v 1.586 2007/08/15 13:04:54 drh Exp $
*/
#ifndef _SQLITEINT_H_
#define _SQLITEINT_H_
#include "sqliteLimit.h"


#if defined(SQLITE_TCL) || defined(TCLSH)
................................................................................
  int nDb;                      /* Number of backends currently in use */
  Db *aDb;                      /* All backends */
  int flags;                    /* Miscellanous flags. See below */
  int errCode;                  /* Most recent error code (SQLITE_*) */
  int errMask;                  /* & result codes with this before returning */
  u8 autoCommit;                /* The auto-commit flag. */
  u8 temp_store;                /* 1: file 2: memory 0: default */

  int nTable;                   /* Number of tables in the database */
  CollSeq *pDfltColl;           /* The default collating sequence (BINARY) */
  i64 lastRowid;                /* ROWID of most recent insert (see above) */
  i64 priorNewRowid;            /* Last randomly generated ROWID */
  int magic;                    /* Magic number for detect library misuse */
  int nChange;                  /* Value returned by sqlite3_changes() */
  int nTotalChange;             /* Value returned by sqlite3_total_changes() */
................................................................................
/*
** Internal function prototypes
*/
int sqlite3StrICmp(const char *, const char *);
int sqlite3StrNICmp(const char *, const char *, int);
int sqlite3IsNumber(const char*, int*, u8);

void *sqlite3Malloc(int,int);
void *sqlite3MallocRaw(int,int);

void *sqlite3Realloc(void*,int);
char *sqlite3StrDup(const char*);
char *sqlite3StrNDup(const char*, int);
# define sqlite3CheckMemory(a,b)
void *sqlite3ReallocOrFree(void*,int);
void sqlite3FreeX(void*);
void *sqlite3MallocX(int);
#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
  int sqlite3AllocSize(void *);
#endif

char *sqlite3MPrintf(const char*, ...);
char *sqlite3VMPrintf(const char*, va_list);
#if defined(SQLITE_TEST) || defined(SQLITE_DEBUG)
  void sqlite3DebugPrintf(const char*, ...);
  void *sqlite3TextToPtr(const char*);
#endif
void sqlite3SetString(char **, ...);
void sqlite3ErrorMsg(Parse*, const char*, ...);
void sqlite3ErrorClear(Parse*);
void sqlite3Dequote(char*);
void sqlite3DequoteExpr(Expr*);
int sqlite3KeywordCode(const unsigned char*, int);
int sqlite3RunParser(Parse*, const char*, char **);
void sqlite3FinishCoding(Parse*);
Expr *sqlite3Expr(int, Expr*, Expr*, const Token*);
Expr *sqlite3ExprOrFree(int, Expr*, Expr*, const Token*);
Expr *sqlite3RegisterExpr(Parse*,Token*);
Expr *sqlite3ExprAnd(Expr*, Expr*);
void sqlite3ExprSpan(Expr*,Token*,Token*);
Expr *sqlite3ExprFunction(ExprList*, Token*);
void sqlite3ExprAssignVarNumber(Parse*, Expr*);
void sqlite3ExprDelete(Expr*);
ExprList *sqlite3ExprListAppend(ExprList*,Expr*,Token*);
void sqlite3ExprListDelete(ExprList*);
int sqlite3Init(sqlite3*, char**);
int sqlite3InitCallback(void*, int, char**, char**);
void sqlite3Pragma(Parse*,Token*,Token*,Token*,int);
void sqlite3ResetInternalSchema(sqlite3*, int);
void sqlite3BeginParse(Parse*,int);
void sqlite3CommitInternalChanges(sqlite3*);
................................................................................
#else
# define sqlite3ViewGetColumnNames(A,B) 0
#endif

void sqlite3DropTable(Parse*, SrcList*, int, int);
void sqlite3DeleteTable(Table*);
void sqlite3Insert(Parse*, SrcList*, ExprList*, Select*, IdList*, int);
void *sqlite3ArrayAllocate(void*,int,int,int*,int*,int*);
IdList *sqlite3IdListAppend(IdList*, Token*);
int sqlite3IdListIndex(IdList*,const char*);
SrcList *sqlite3SrcListAppend(SrcList*, Token*, Token*);
SrcList *sqlite3SrcListAppendFromTerm(SrcList*, Token*, Token*, Token*,
                                      Select*, Expr*, IdList*);
void sqlite3SrcListShiftJoinType(SrcList*);
void sqlite3SrcListAssignCursors(Parse*, SrcList*);
void sqlite3IdListDelete(IdList*);
void sqlite3SrcListDelete(SrcList*);
void sqlite3CreateIndex(Parse*,Token*,Token*,SrcList*,ExprList*,int,Token*,
                        Token*, int, int);
void sqlite3DropIndex(Parse*, SrcList*, int);
int sqlite3Select(Parse*, Select*, int, int, Select*, int, int*, char *aff);
Select *sqlite3SelectNew(ExprList*,SrcList*,Expr*,ExprList*,Expr*,ExprList*,
                        int,Expr*,Expr*);
void sqlite3SelectDelete(Select*);
Table *sqlite3SrcListLookup(Parse*, SrcList*);
int sqlite3IsReadOnly(Parse*, Table*, int);
void sqlite3OpenTable(Parse*, int iCur, int iDb, Table*, int);
void sqlite3DeleteFrom(Parse*, SrcList*, Expr*);
void sqlite3Update(Parse*, SrcList*, ExprList*, Expr*, int);
WhereInfo *sqlite3WhereBegin(Parse*, SrcList*, Expr*, ExprList**);
................................................................................
Table *sqlite3FindTable(sqlite3*,const char*, const char*);
Table *sqlite3LocateTable(Parse*,const char*, const char*);
Index *sqlite3FindIndex(sqlite3*,const char*, const char*);
void sqlite3UnlinkAndDeleteTable(sqlite3*,int,const char*);
void sqlite3UnlinkAndDeleteIndex(sqlite3*,int,const char*);
void sqlite3Vacuum(Parse*);
int sqlite3RunVacuum(char**, sqlite3*);
char *sqlite3NameFromToken(Token*);
int sqlite3ExprCompare(Expr*, Expr*);
int sqliteFuncId(Token*);
int sqlite3ExprResolveNames(NameContext *, Expr *);
int sqlite3ExprAnalyzeAggregates(NameContext*, Expr*);
int sqlite3ExprAnalyzeAggList(NameContext*,ExprList*);
Vdbe *sqlite3GetVdbe(Parse*);
Expr *sqlite3CreateIdExpr(const char*);
void sqlite3Randomness(int, void*);
void sqlite3RollbackAll(sqlite3*);
................................................................................
void sqlite3GenerateRowDelete(sqlite3*, Vdbe*, Table*, int, int);
void sqlite3GenerateRowIndexDelete(Vdbe*, Table*, int, char*);
void sqlite3GenerateIndexKey(Vdbe*, Index*, int);
void sqlite3GenerateConstraintChecks(Parse*,Table*,int,char*,int,int,int,int);
void sqlite3CompleteInsertion(Parse*, Table*, int, char*, int, int, int, int);
void sqlite3OpenTableAndIndices(Parse*, Table*, int, int);
void sqlite3BeginWriteOperation(Parse*, int, int);
Expr *sqlite3ExprDup(Expr*);
void sqlite3TokenCopy(Token*, Token*);
ExprList *sqlite3ExprListDup(ExprList*);
SrcList *sqlite3SrcListDup(SrcList*);
IdList *sqlite3IdListDup(IdList*);
Select *sqlite3SelectDup(Select*);
FuncDef *sqlite3FindFunction(sqlite3*,const char*,int,int,u8,int);
void sqlite3RegisterBuiltinFunctions(sqlite3*);
void sqlite3RegisterDateTimeFunctions(sqlite3*);
int sqlite3SafetyOn(sqlite3*);
int sqlite3SafetyOff(sqlite3*);
int sqlite3SafetyCheck(sqlite3*);
void sqlite3ChangeCookie(sqlite3*, Vdbe*, int);
................................................................................
  void sqlite3DropTrigger(Parse*, SrcList*, int);
  void sqlite3DropTriggerPtr(Parse*, Trigger*);
  int sqlite3TriggersExist(Parse*, Table*, int, ExprList*);
  int sqlite3CodeRowTrigger(Parse*, int, ExprList*, int, Table *, int, int, 
                           int, int);
  void sqliteViewTriggers(Parse*, Table*, Expr*, int, ExprList*);
  void sqlite3DeleteTriggerStep(TriggerStep*);
  TriggerStep *sqlite3TriggerSelectStep(Select*);
  TriggerStep *sqlite3TriggerInsertStep(Token*, IdList*, ExprList*,Select*,int);

  TriggerStep *sqlite3TriggerUpdateStep(Token*, ExprList*, Expr*, int);
  TriggerStep *sqlite3TriggerDeleteStep(Token*, Expr*);
  void sqlite3DeleteTrigger(Trigger*);
  void sqlite3UnlinkAndDeleteTrigger(sqlite3*,int,const char*);
#else
# define sqlite3TriggersExist(A,B,C,D,E,F) 0
# define sqlite3DeleteTrigger(A)
# define sqlite3DropTriggerPtr(A,B)
# define sqlite3UnlinkAndDeleteTrigger(A,B,C)
................................................................................
  #define sqlite3TableLock(v,w,x,y,z)
#endif

#ifdef SQLITE_TEST
  int sqlite3Utf8To8(unsigned char*);
#endif

#ifdef SQLITE_MEMDEBUG

  void sqlite3MallocDisallow(void);
  void sqlite3MallocAllow(void);
  int sqlite3TestMallocFail(void);
#else
  #define sqlite3TestMallocFail() 0

  #define sqlite3MallocDisallow()
  #define sqlite3MallocAllow()
#endif

#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
  void *sqlite3ThreadSafeMalloc(int);
  void sqlite3ThreadSafeFree(void *);
#else
  #define sqlite3ThreadSafeMalloc sqlite3MallocX
  #define sqlite3ThreadSafeFree sqlite3FreeX
#endif

#ifdef SQLITE_OMIT_VIRTUALTABLE
#  define sqlite3VtabClear(X)
#  define sqlite3VtabSync(X,Y) (Y)
#  define sqlite3VtabRollback(X)
#  define sqlite3VtabCommit(X)
#else

**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** Internal interface definitions for SQLite.
**
** @(#) $Id: sqliteInt.h,v 1.587 2007/08/16 04:30:40 drh Exp $
*/
#ifndef _SQLITEINT_H_
#define _SQLITEINT_H_
#include "sqliteLimit.h"


#if defined(SQLITE_TCL) || defined(TCLSH)
................................................................................
  int nDb;                      /* Number of backends currently in use */
  Db *aDb;                      /* All backends */
  int flags;                    /* Miscellanous flags. See below */
  int errCode;                  /* Most recent error code (SQLITE_*) */
  int errMask;                  /* & result codes with this before returning */
  u8 autoCommit;                /* The auto-commit flag. */
  u8 temp_store;                /* 1: file 2: memory 0: default */
  u8 mallocFailed;              /* True if we have seen a malloc failure */
  int nTable;                   /* Number of tables in the database */
  CollSeq *pDfltColl;           /* The default collating sequence (BINARY) */
  i64 lastRowid;                /* ROWID of most recent insert (see above) */
  i64 priorNewRowid;            /* Last randomly generated ROWID */
  int magic;                    /* Magic number for detect library misuse */
  int nChange;                  /* Value returned by sqlite3_changes() */
  int nTotalChange;             /* Value returned by sqlite3_total_changes() */
................................................................................
/*
** Internal function prototypes
*/
int sqlite3StrICmp(const char *, const char *);
int sqlite3StrNICmp(const char *, const char *, int);
int sqlite3IsNumber(const char*, int*, u8);

void *sqlite3MallocZero(unsigned);
void *sqlite3DbMallocZero(sqlite3*, unsigned);
void *sqlite3DbMallocRaw(sqlite3*, unsigned);
void *sqlite3ReallocOrFree(sqlite3*,void*,int);
char *sqlite3StrDup(const char*);
char *sqlite3StrNDup(const char*, int);

char *sqlite3DbStrDup(sqlite3*,const char*);
char *sqlite3DbStrNDup(sqlite3*,const char*, int);





char *sqlite3MPrintf(sqlite3*,const char*, ...);
char *sqlite3VMPrintf(sqlite3*,const char*, va_list);
#if defined(SQLITE_TEST) || defined(SQLITE_DEBUG)
  void sqlite3DebugPrintf(const char*, ...);
  void *sqlite3TextToPtr(const char*);
#endif
void sqlite3SetString(char **, ...);
void sqlite3ErrorMsg(Parse*, const char*, ...);
void sqlite3ErrorClear(Parse*);
void sqlite3Dequote(char*);
void sqlite3DequoteExpr(sqlite3*, Expr*);
int sqlite3KeywordCode(const unsigned char*, int);
int sqlite3RunParser(Parse*, const char*, char **);
void sqlite3FinishCoding(Parse*);
Expr *sqlite3Expr(int, Expr*, Expr*, const Token*);
Expr *sqlite3PExpr(Parse*, int, Expr*, Expr*, const Token*);
Expr *sqlite3RegisterExpr(Parse*,Token*);
Expr *sqlite3ExprAnd(sqlite*,Expr*, Expr*);
void sqlite3ExprSpan(Expr*,Token*,Token*);
Expr *sqlite3ExprFunction(Parse*,ExprList*, Token*);
void sqlite3ExprAssignVarNumber(Parse*, Expr*);
void sqlite3ExprDelete(Expr*);
ExprList *sqlite3ExprListAppend(Parse*,ExprList*,Expr*,Token*);
void sqlite3ExprListDelete(ExprList*);
int sqlite3Init(sqlite3*, char**);
int sqlite3InitCallback(void*, int, char**, char**);
void sqlite3Pragma(Parse*,Token*,Token*,Token*,int);
void sqlite3ResetInternalSchema(sqlite3*, int);
void sqlite3BeginParse(Parse*,int);
void sqlite3CommitInternalChanges(sqlite3*);
................................................................................
#else
# define sqlite3ViewGetColumnNames(A,B) 0
#endif

void sqlite3DropTable(Parse*, SrcList*, int, int);
void sqlite3DeleteTable(Table*);
void sqlite3Insert(Parse*, SrcList*, ExprList*, Select*, IdList*, int);
void *sqlite3ArrayAllocate(sqlite3*,void*,int,int,int*,int*,int*);
IdList *sqlite3IdListAppend(sqlite3*, IdList*, Token*);
int sqlite3IdListIndex(IdList*,const char*);
SrcList *sqlite3SrcListAppend(sqlite3*, SrcList*, Token*, Token*);
SrcList *sqlite3SrcListAppendFromTerm(Parse*, SrcList*, Token*, Token*, Token*,
                                      Select*, Expr*, IdList*);
void sqlite3SrcListShiftJoinType(SrcList*);
void sqlite3SrcListAssignCursors(Parse*, SrcList*);
void sqlite3IdListDelete(IdList*);
void sqlite3SrcListDelete(SrcList*);
void sqlite3CreateIndex(Parse*,Token*,Token*,SrcList*,ExprList*,int,Token*,
                        Token*, int, int);
void sqlite3DropIndex(Parse*, SrcList*, int);
int sqlite3Select(Parse*, Select*, int, int, Select*, int, int*, char *aff);
Select *sqlite3SelectNew(Parse*,ExprList*,SrcList*,Expr*,ExprList*,
                         Expr*,ExprList*,int,Expr*,Expr*);
void sqlite3SelectDelete(Select*);
Table *sqlite3SrcListLookup(Parse*, SrcList*);
int sqlite3IsReadOnly(Parse*, Table*, int);
void sqlite3OpenTable(Parse*, int iCur, int iDb, Table*, int);
void sqlite3DeleteFrom(Parse*, SrcList*, Expr*);
void sqlite3Update(Parse*, SrcList*, ExprList*, Expr*, int);
WhereInfo *sqlite3WhereBegin(Parse*, SrcList*, Expr*, ExprList**);
................................................................................
Table *sqlite3FindTable(sqlite3*,const char*, const char*);
Table *sqlite3LocateTable(Parse*,const char*, const char*);
Index *sqlite3FindIndex(sqlite3*,const char*, const char*);
void sqlite3UnlinkAndDeleteTable(sqlite3*,int,const char*);
void sqlite3UnlinkAndDeleteIndex(sqlite3*,int,const char*);
void sqlite3Vacuum(Parse*);
int sqlite3RunVacuum(char**, sqlite3*);
char *sqlite3NameFromToken(sqlite3*, Token*);
int sqlite3ExprCompare(Expr*, Expr*);

int sqlite3ExprResolveNames(NameContext *, Expr *);
int sqlite3ExprAnalyzeAggregates(NameContext*, Expr*);
int sqlite3ExprAnalyzeAggList(NameContext*,ExprList*);
Vdbe *sqlite3GetVdbe(Parse*);
Expr *sqlite3CreateIdExpr(const char*);
void sqlite3Randomness(int, void*);
void sqlite3RollbackAll(sqlite3*);
................................................................................
void sqlite3GenerateRowDelete(sqlite3*, Vdbe*, Table*, int, int);
void sqlite3GenerateRowIndexDelete(Vdbe*, Table*, int, char*);
void sqlite3GenerateIndexKey(Vdbe*, Index*, int);
void sqlite3GenerateConstraintChecks(Parse*,Table*,int,char*,int,int,int,int);
void sqlite3CompleteInsertion(Parse*, Table*, int, char*, int, int, int, int);
void sqlite3OpenTableAndIndices(Parse*, Table*, int, int);
void sqlite3BeginWriteOperation(Parse*, int, int);
Expr *sqlite3ExprDup(sqlite3*,Expr*);
void sqlite3TokenCopy(sqlite3*,Token*, Token*);
ExprList *sqlite3ExprListDup(sqlite3*,ExprList*);
SrcList *sqlite3SrcListDup(sqlite3*,SrcList*);
IdList *sqlite3IdListDup(sqlite3*,IdList*);
Select *sqlite3SelectDup(sqlite3*,Select*);
FuncDef *sqlite3FindFunction(sqlite3*,const char*,int,int,u8,int);
void sqlite3RegisterBuiltinFunctions(sqlite3*);
void sqlite3RegisterDateTimeFunctions(sqlite3*);
int sqlite3SafetyOn(sqlite3*);
int sqlite3SafetyOff(sqlite3*);
int sqlite3SafetyCheck(sqlite3*);
void sqlite3ChangeCookie(sqlite3*, Vdbe*, int);
................................................................................
  void sqlite3DropTrigger(Parse*, SrcList*, int);
  void sqlite3DropTriggerPtr(Parse*, Trigger*);
  int sqlite3TriggersExist(Parse*, Table*, int, ExprList*);
  int sqlite3CodeRowTrigger(Parse*, int, ExprList*, int, Table *, int, int, 
                           int, int);
  void sqliteViewTriggers(Parse*, Table*, Expr*, int, ExprList*);
  void sqlite3DeleteTriggerStep(TriggerStep*);
  TriggerStep *sqlite3TriggerSelectStep(sqlite3*,Select*);
  TriggerStep *sqlite3TriggerInsertStep(sqlite3*,Token*, IdList*,
                                        ExprList*,Select*,int);
  TriggerStep *sqlite3TriggerUpdateStep(sqlite3*,Token*,ExprList*, Expr*, int);
  TriggerStep *sqlite3TriggerDeleteStep(sqlite3*,Token*, Expr*);
  void sqlite3DeleteTrigger(Trigger*);
  void sqlite3UnlinkAndDeleteTrigger(sqlite3*,int,const char*);
#else
# define sqlite3TriggersExist(A,B,C,D,E,F) 0
# define sqlite3DeleteTrigger(A)
# define sqlite3DropTriggerPtr(A,B)
# define sqlite3UnlinkAndDeleteTrigger(A,B,C)
................................................................................
  #define sqlite3TableLock(v,w,x,y,z)
#endif

#ifdef SQLITE_TEST
  int sqlite3Utf8To8(unsigned char*);
#endif


/*
** FIX ME:  create these routines




*/
#define sqlite3MallocDisallow()
#define sqlite3MallocAllow()










#ifdef SQLITE_OMIT_VIRTUALTABLE
#  define sqlite3VtabClear(X)
#  define sqlite3VtabSync(X,Y) (Y)
#  define sqlite3VtabRollback(X)
#  define sqlite3VtabCommit(X)
#else

**    May you share freely, never taking more than you give.
**
*************************************************************************
** Code for testing all sorts of SQLite interfaces.  This code
** is not included in the SQLite library.  It is used for automated
** testing of the SQLite library.
**
** $Id: test1.c,v 1.259 2007/08/08 12:11:21 drh Exp $
*/
#include "sqliteInt.h"
#include "tcl.h"
#include "os.h"
#include <stdlib.h>
#include <string.h>

................................................................................
  char *zResult = 0;
  int i;

  for(i=2; i<argc; i++){
    zResult = sqlite3MPrintf("%z%s%s", zResult, argv[1], argv[i]);
  }
  Tcl_AppendResult(interp, zResult, 0);
  sqliteFree(zResult);
  return TCL_OK;
}

/*
** Usage:  sqlite3_mprintf_n_test  STRING
**
** Test the %n format of sqliteMPrintf().  Return the length of the
................................................................................
  Tcl_Interp *interp,    /* The TCL interpreter that invoked this command */
  int argc,              /* Number of arguments */
  char **argv            /* Text of each argument */
){
  char *zStr;
  int n = 0;
  zStr = sqlite3MPrintf("%s%n", argv[1], &n);
  sqliteFree(zStr);
  Tcl_SetObjResult(interp, Tcl_NewIntObj(n));
  return TCL_OK;
}

/*
** Usage:  sqlite3_snprintf_int  SIZE FORMAT  INT
**
................................................................................
** Append text to a dstr
*/
static void dstrAppend(struct dstr *p, const char *z, int divider){
  int n = strlen(z);
  if( p->nUsed + n + 2 > p->nAlloc ){
    char *zNew;
    p->nAlloc = p->nAlloc*2 + n + 200;
    zNew = sqliteRealloc(p->z, p->nAlloc);
    if( zNew==0 ){
      sqliteFree(p->z);
      memset(p, 0, sizeof(*p));
      return;
    }
    p->z = zNew;
  }
  if( divider && p->nUsed>0 ){
    p->z[p->nUsed++] = divider;
................................................................................
){
  struct dstr x;
  memset(&x, 0, sizeof(x));
  (void)sqlite3_exec((sqlite3*)sqlite3_user_data(context),
      (char*)sqlite3_value_text(argv[0]),
      execFuncCallback, &x, 0);
  sqlite3_result_text(context, x.z, x.nUsed, SQLITE_TRANSIENT);
  sqliteFree(x.z);
}

/*
** Implementation of tkt2213func(), a scalar function that takes exactly
** one argument. It has two interesting features:
**
** * It calls sqlite3_value_text() 3 times on the argument sqlite3_value*.
................................................................................
  }

#ifndef SQLITE_OMIT_UTF16
  /* Use the sqlite3_create_function16() API here. Mainly for fun, but also 
  ** because it is not tested anywhere else. */
  if( rc==SQLITE_OK ){
    sqlite3_value *pVal;
#ifdef SQLITE_MEMDEBUG
    if( sqlite3_iMallocFail>0 ){
      sqlite3_iMallocFail++;
    }
#endif 
    pVal = sqlite3ValueNew();
    sqlite3ValueSetStr(pVal, -1, "x_sqlite_exec", SQLITE_UTF8, SQLITE_STATIC);
    rc = sqlite3_create_function16(db, 
................................................................................
  memcpy(&r, &d, sizeof(r));
  z = sqlite3_mprintf(argv[1], r);
  Tcl_AppendResult(interp, z, 0);
  sqlite3_free(z);
  return TCL_OK;
}

/*
** Usage: sqlite_malloc_fail N  ?REPEAT-INTERVAL?
**
** Rig sqliteMalloc() to fail on the N-th call and every REPEAT-INTERVAL call
** after that.  If REPEAT-INTERVAL is 0 or is omitted, then only a single
** malloc will fail.  If REPEAT-INTERVAL is 1 then all mallocs after the
** first failure will continue to fail on every call.  If REPEAT-INTERVAL is
** 2 then every other malloc will fail.  And so forth.
**
** Turn off this mechanism and reset the sqlite3ThreadData()->mallocFailed 
** variable if N==0.
*/
#ifdef SQLITE_MEMDEBUG
static int sqlite_malloc_fail(
  void *NotUsed,
  Tcl_Interp *interp,    /* The TCL interpreter that invoked this command */
  int argc,              /* Number of arguments */
  char **argv            /* Text of each argument */
){
  int n;
  int rep;
  if( argc!=2 && argc!=3 ){
    Tcl_AppendResult(interp, "wrong # args: should be \"", argv[0], " N\"", 0);
    return TCL_ERROR;
  }
  if( Tcl_GetInt(interp, argv[1], &n) ) return TCL_ERROR;
  if( argc==3 ){
    if( Tcl_GetInt(interp, argv[2], &rep) ) return TCL_ERROR;
  }else{
    rep = 0;
  }
  sqlite3_iMallocFail = n;
  sqlite3_iMallocReset = rep;
  return TCL_OK;
}
#endif

/*
** Usage: sqlite_malloc_stat
**
** Return the number of prior calls to sqliteMalloc() and sqliteFree().
*/
#ifdef SQLITE_MEMDEBUG
static int sqlite_malloc_stat(
  void *NotUsed,
  Tcl_Interp *interp,    /* The TCL interpreter that invoked this command */
  int argc,              /* Number of arguments */
  char **argv            /* Text of each argument */
){
  char zBuf[200];
  sprintf(zBuf, "%d %d %d", sqlite3_nMalloc,sqlite3_nFree,sqlite3_iMallocFail);
  Tcl_AppendResult(interp, zBuf, 0);
  return TCL_OK;
}

/*
** This function implements a Tcl command that may be invoked using any of
** the four forms enumerated below.
**
** sqlite_malloc_outstanding
**     Return a summary of all unfreed blocks of memory allocated by the
**     current thread. See comments above function sqlite3OutstandingMallocs() 
**     in util.c for a description of the returned value.
**
** sqlite_malloc_outstanding -bytes
**     Return the total amount of unfreed memory (in bytes) allocated by 
**     this thread.
**
** sqlite_malloc_outstanding -maxbytes
**     Return the maximum amount of dynamic memory in use at one time 
**     by this thread.
**
** sqlite_malloc_outstanding -clearmaxbytes
**     Set the value returned by [sqlite_malloc_outstanding -maxbytes]
**     to the current value of [sqlite_malloc_outstanding -bytes]. 
*/
static int sqlite_malloc_outstanding(
  ClientData clientData,
  Tcl_Interp *interp,    /* The TCL interpreter that invoked this command */
  int objc,              /* Number of arguments */
  Tcl_Obj *CONST objv[]  /* Command arguments */
){
  extern int sqlite3OutstandingMallocs(Tcl_Interp *interp);

#if defined(SQLITE_DEBUG) && defined(SQLITE_MEMDEBUG) && SQLITE_MEMDEBUG>1
  if( objc==2 ){
    const char *zArg = Tcl_GetString(objv[1]);
#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
    ThreadData const *pTd = sqlite3ThreadDataReadOnly();
    if( 0==strcmp(zArg, "-bytes") ){
      Tcl_SetObjResult(interp, Tcl_NewIntObj(pTd->nAlloc));
    }else if( 0==strcmp(zArg, "-clearmaxbytes") ){
      sqlite3_nMaxAlloc = pTd->nAlloc;
    }else 
#endif
    if( 0==strcmp(zArg, "-maxbytes") ){
      Tcl_SetObjResult(interp, Tcl_NewWideIntObj(sqlite3_nMaxAlloc));
    }else{
      Tcl_AppendResult(interp, "bad option \"", zArg, 
        "\": must be -bytes, -maxbytes or -clearmaxbytes", 0
      );
      return TCL_ERROR;
    }

    return TCL_OK;
  }

  if( objc!=1 ){
    Tcl_WrongNumArgs(interp, 1, objv, "?-bytes?");
    return TCL_ERROR;
  }

  return sqlite3OutstandingMallocs(interp);
#else
  return TCL_OK;
#endif
}
#endif

/*
** Usage: sqlite3_enable_shared_cache      BOOLEAN
**
*/
#if !defined(SQLITE_OMIT_SHARED_CACHE)
static int test_enable_shared(
  ClientData clientData, /* Pointer to sqlite3_enable_XXX function */
................................................................................
     { "sqlite3_exec_nr",               (Tcl_CmdProc*)test_exec_nr          },
     { "sqlite3_get_table_printf",      (Tcl_CmdProc*)test_get_table_printf },
     { "sqlite3_close",                 (Tcl_CmdProc*)sqlite_test_close     },
     { "sqlite3_create_function",       (Tcl_CmdProc*)test_create_function  },
     { "sqlite3_create_aggregate",      (Tcl_CmdProc*)test_create_aggregate },
     { "sqlite_register_test_function", (Tcl_CmdProc*)test_register_func    },
     { "sqlite_abort",                  (Tcl_CmdProc*)sqlite_abort          },
#ifdef SQLITE_MEMDEBUG
     { "sqlite_malloc_fail",            (Tcl_CmdProc*)sqlite_malloc_fail    },
     { "sqlite_malloc_stat",            (Tcl_CmdProc*)sqlite_malloc_stat    },
#endif
     { "sqlite_bind",                   (Tcl_CmdProc*)test_bind             },
     { "breakpoint",                    (Tcl_CmdProc*)test_breakpoint       },
     { "sqlite3_key",                   (Tcl_CmdProc*)test_key              },
     { "sqlite3_rekey",                 (Tcl_CmdProc*)test_rekey            },
     { "sqlite_set_magic",              (Tcl_CmdProc*)sqlite_set_magic      },
     { "sqlite3_interrupt",             (Tcl_CmdProc*)test_interrupt        },
     { "sqlite_delete_function",        (Tcl_CmdProc*)delete_function       },
................................................................................
     { "sqlite3OsUnlock",         test_sqlite3OsUnlock, 0    },
#endif
#ifndef SQLITE_OMIT_UTF16
     { "add_test_collate",        test_collate, 0            },
     { "add_test_collate_needed", test_collate_needed, 0     },
     { "add_test_function",       test_function, 0           },
#endif
#ifdef SQLITE_MEMDEBUG
     { "sqlite_malloc_outstanding", sqlite_malloc_outstanding, 0},
#endif
     { "sqlite3_test_errstr",     test_errstr, 0             },
     { "tcl_variable_type",       tcl_variable_type, 0       },
#ifndef SQLITE_OMIT_SHARED_CACHE
     { "sqlite3_enable_shared_cache", test_enable_shared, 0  },
     { "sqlite3_shared_cache_report", sqlite3BtreeSharedCacheReport, 0},
#endif
     { "sqlite3_libversion_number", test_libversion_number, 0  },
................................................................................
#if OS_UNIX && defined(SQLITE_TEST) && defined(THREADSAFE) && THREADSAFE
  Tcl_LinkVar(interp, "threadsOverrideEachOthersLocks",
      (char*)&threadsOverrideEachOthersLocks, TCL_LINK_INT);
#endif
#ifndef SQLITE_OMIT_UTF16
  Tcl_LinkVar(interp, "sqlite_last_needed_collation",
      (char*)&pzNeededCollation, TCL_LINK_STRING|TCL_LINK_READ_ONLY);
#endif
#ifdef SQLITE_MEMDEBUG
  {
    extern char *sqlite3_malloc_id;
    extern int sqlite3_mallocfail_trace;
    Tcl_LinkVar(interp, "sqlite_malloc_id",
        (char*)&sqlite3_malloc_id, TCL_LINK_STRING);
    Tcl_LinkVar(interp, "sqlite3_mallocfail_trace",
        (char*)&sqlite3_mallocfail_trace, TCL_LINK_INT);
  }
#endif
#if OS_WIN
  Tcl_LinkVar(interp, "sqlite_os_type",
      (char*)&sqlite3_os_type, TCL_LINK_INT);
#endif
#ifdef SQLITE_TEST
  Tcl_LinkVar(interp, "sqlite_query_plan",

**    May you share freely, never taking more than you give.
**
*************************************************************************
** Code for testing all sorts of SQLite interfaces.  This code
** is not included in the SQLite library.  It is used for automated
** testing of the SQLite library.
**
** $Id: test1.c,v 1.260 2007/08/16 04:30:40 drh Exp $
*/
#include "sqliteInt.h"
#include "tcl.h"
#include "os.h"
#include <stdlib.h>
#include <string.h>

................................................................................
  char *zResult = 0;
  int i;

  for(i=2; i<argc; i++){
    zResult = sqlite3MPrintf("%z%s%s", zResult, argv[1], argv[i]);
  }
  Tcl_AppendResult(interp, zResult, 0);
  sqlite3_free(zResult);
  return TCL_OK;
}

/*
** Usage:  sqlite3_mprintf_n_test  STRING
**
** Test the %n format of sqliteMPrintf().  Return the length of the
................................................................................
  Tcl_Interp *interp,    /* The TCL interpreter that invoked this command */
  int argc,              /* Number of arguments */
  char **argv            /* Text of each argument */
){
  char *zStr;
  int n = 0;
  zStr = sqlite3MPrintf("%s%n", argv[1], &n);
  sqlite3_free(zStr);
  Tcl_SetObjResult(interp, Tcl_NewIntObj(n));
  return TCL_OK;
}

/*
** Usage:  sqlite3_snprintf_int  SIZE FORMAT  INT
**
................................................................................
** Append text to a dstr
*/
static void dstrAppend(struct dstr *p, const char *z, int divider){
  int n = strlen(z);
  if( p->nUsed + n + 2 > p->nAlloc ){
    char *zNew;
    p->nAlloc = p->nAlloc*2 + n + 200;
    zNew = sqlite3_realloc(p->z, p->nAlloc);
    if( zNew==0 ){
      sqlite3_free(p->z);
      memset(p, 0, sizeof(*p));
      return;
    }
    p->z = zNew;
  }
  if( divider && p->nUsed>0 ){
    p->z[p->nUsed++] = divider;
................................................................................
){
  struct dstr x;
  memset(&x, 0, sizeof(x));
  (void)sqlite3_exec((sqlite3*)sqlite3_user_data(context),
      (char*)sqlite3_value_text(argv[0]),
      execFuncCallback, &x, 0);
  sqlite3_result_text(context, x.z, x.nUsed, SQLITE_TRANSIENT);
  sqlite3_free(x.z);
}

/*
** Implementation of tkt2213func(), a scalar function that takes exactly
** one argument. It has two interesting features:
**
** * It calls sqlite3_value_text() 3 times on the argument sqlite3_value*.
................................................................................
  }

#ifndef SQLITE_OMIT_UTF16
  /* Use the sqlite3_create_function16() API here. Mainly for fun, but also 
  ** because it is not tested anywhere else. */
  if( rc==SQLITE_OK ){
    sqlite3_value *pVal;
#ifdef 0
    if( sqlite3_iMallocFail>0 ){
      sqlite3_iMallocFail++;
    }
#endif 
    pVal = sqlite3ValueNew();
    sqlite3ValueSetStr(pVal, -1, "x_sqlite_exec", SQLITE_UTF8, SQLITE_STATIC);
    rc = sqlite3_create_function16(db, 
................................................................................
  memcpy(&r, &d, sizeof(r));
  z = sqlite3_mprintf(argv[1], r);
  Tcl_AppendResult(interp, z, 0);
  sqlite3_free(z);
  return TCL_OK;
}
























































































































/*
** Usage: sqlite3_enable_shared_cache      BOOLEAN
**
*/
#if !defined(SQLITE_OMIT_SHARED_CACHE)
static int test_enable_shared(
  ClientData clientData, /* Pointer to sqlite3_enable_XXX function */
................................................................................
     { "sqlite3_exec_nr",               (Tcl_CmdProc*)test_exec_nr          },
     { "sqlite3_get_table_printf",      (Tcl_CmdProc*)test_get_table_printf },
     { "sqlite3_close",                 (Tcl_CmdProc*)sqlite_test_close     },
     { "sqlite3_create_function",       (Tcl_CmdProc*)test_create_function  },
     { "sqlite3_create_aggregate",      (Tcl_CmdProc*)test_create_aggregate },
     { "sqlite_register_test_function", (Tcl_CmdProc*)test_register_func    },
     { "sqlite_abort",                  (Tcl_CmdProc*)sqlite_abort          },




     { "sqlite_bind",                   (Tcl_CmdProc*)test_bind             },
     { "breakpoint",                    (Tcl_CmdProc*)test_breakpoint       },
     { "sqlite3_key",                   (Tcl_CmdProc*)test_key              },
     { "sqlite3_rekey",                 (Tcl_CmdProc*)test_rekey            },
     { "sqlite_set_magic",              (Tcl_CmdProc*)sqlite_set_magic      },
     { "sqlite3_interrupt",             (Tcl_CmdProc*)test_interrupt        },
     { "sqlite_delete_function",        (Tcl_CmdProc*)delete_function       },
................................................................................
     { "sqlite3OsUnlock",         test_sqlite3OsUnlock, 0    },
#endif
#ifndef SQLITE_OMIT_UTF16
     { "add_test_collate",        test_collate, 0            },
     { "add_test_collate_needed", test_collate_needed, 0     },
     { "add_test_function",       test_function, 0           },
#endif



     { "sqlite3_test_errstr",     test_errstr, 0             },
     { "tcl_variable_type",       tcl_variable_type, 0       },
#ifndef SQLITE_OMIT_SHARED_CACHE
     { "sqlite3_enable_shared_cache", test_enable_shared, 0  },
     { "sqlite3_shared_cache_report", sqlite3BtreeSharedCacheReport, 0},
#endif
     { "sqlite3_libversion_number", test_libversion_number, 0  },
................................................................................
#if OS_UNIX && defined(SQLITE_TEST) && defined(THREADSAFE) && THREADSAFE
  Tcl_LinkVar(interp, "threadsOverrideEachOthersLocks",
      (char*)&threadsOverrideEachOthersLocks, TCL_LINK_INT);
#endif
#ifndef SQLITE_OMIT_UTF16
  Tcl_LinkVar(interp, "sqlite_last_needed_collation",
      (char*)&pzNeededCollation, TCL_LINK_STRING|TCL_LINK_READ_ONLY);










#endif
#if OS_WIN
  Tcl_LinkVar(interp, "sqlite_os_type",
      (char*)&sqlite3_os_type, TCL_LINK_INT);
#endif
#ifdef SQLITE_TEST
  Tcl_LinkVar(interp, "sqlite_query_plan",

**    May you share freely, never taking more than you give.
**
*************************************************************************
** Code for testing the btree.c module in SQLite.  This code
** is not included in the SQLite library.  It is used for automated
** testing of the SQLite library.
**
** $Id: test3.c,v 1.75 2007/05/17 14:45:13 danielk1977 Exp $
*/
#include "sqliteInt.h"
#include "pager.h"
#include "btree.h"
#include "tcl.h"
#include <stdlib.h>
#include <string.h>
................................................................................
  if( argc<3 ){
    Tcl_AppendResult(interp, "wrong # args: should be \"", argv[0],
       " ID ROOT ...\"", 0);
    return TCL_ERROR;
  }
  pBt = sqlite3TextToPtr(argv[1]);
  nRoot = argc-2;
  aRoot = (int*)malloc( sizeof(int)*(argc-2) );
  for(i=0; i<argc-2; i++){
    if( Tcl_GetInt(interp, argv[i+2], &aRoot[i]) ) return TCL_ERROR;
  }
#ifndef SQLITE_OMIT_INTEGRITY_CHECK
  zResult = sqlite3BtreeIntegrityCheck(pBt, aRoot, nRoot, 10000, &nErr);
#else
  zResult = 0;
#endif
  free((void*)aRoot);
  if( zResult ){
    Tcl_AppendResult(interp, zResult, 0);
    sqliteFree(zResult); 
  }
  return TCL_OK;
}

................................................................................
  pCur = sqlite3TextToPtr(argv[1]);
  sqlite3BtreeKeySize(pCur, (i64*)&n);
  if( sqlite3BtreeFlags(pCur) & BTREE_INTKEY ){
    char zBuf2[60];
    sqlite3_snprintf(sizeof(zBuf2),zBuf2, "%llu", n);
    Tcl_AppendResult(interp, zBuf2, 0);
  }else{
    zBuf = malloc( n+1 );
    rc = sqlite3BtreeKey(pCur, 0, n, zBuf);
    if( rc ){
      Tcl_AppendResult(interp, errorName(rc), 0);
      return TCL_ERROR;
    }
    zBuf[n] = 0;
    Tcl_AppendResult(interp, zBuf, 0);
    free(zBuf);
  }
  return SQLITE_OK;
}

/*
** Usage:   btree_data ID ?N?
**
................................................................................
  }
  pCur = sqlite3TextToPtr(argv[1]);
  if( argc==2 ){
    sqlite3BtreeDataSize(pCur, &n);
  }else{
    n = atoi(argv[2]);
  }
  zBuf = malloc( n+1 );
  rc = sqlite3BtreeData(pCur, 0, n, zBuf);
  if( rc ){
    Tcl_AppendResult(interp, errorName(rc), 0);
    free(zBuf);
    return TCL_ERROR;
  }
  zBuf[n] = 0;
  Tcl_AppendResult(interp, zBuf, 0);
  free(zBuf);
  return SQLITE_OK;
}

/*
** Usage:   btree_fetch_key ID AMT
**
** Use the sqlite3BtreeKeyFetch() routine to get AMT bytes of the key.

**    May you share freely, never taking more than you give.
**
*************************************************************************
** Code for testing the btree.c module in SQLite.  This code
** is not included in the SQLite library.  It is used for automated
** testing of the SQLite library.
**
** $Id: test3.c,v 1.76 2007/08/16 04:30:40 drh Exp $
*/
#include "sqliteInt.h"
#include "pager.h"
#include "btree.h"
#include "tcl.h"
#include <stdlib.h>
#include <string.h>
................................................................................
  if( argc<3 ){
    Tcl_AppendResult(interp, "wrong # args: should be \"", argv[0],
       " ID ROOT ...\"", 0);
    return TCL_ERROR;
  }
  pBt = sqlite3TextToPtr(argv[1]);
  nRoot = argc-2;
  aRoot = (int*)sqlite3_malloc( sizeof(int)*(argc-2) );
  for(i=0; i<argc-2; i++){
    if( Tcl_GetInt(interp, argv[i+2], &aRoot[i]) ) return TCL_ERROR;
  }
#ifndef SQLITE_OMIT_INTEGRITY_CHECK
  zResult = sqlite3BtreeIntegrityCheck(pBt, aRoot, nRoot, 10000, &nErr);
#else
  zResult = 0;
#endif
  sqlite3_free((void*)aRoot);
  if( zResult ){
    Tcl_AppendResult(interp, zResult, 0);
    sqliteFree(zResult); 
  }
  return TCL_OK;
}

................................................................................
  pCur = sqlite3TextToPtr(argv[1]);
  sqlite3BtreeKeySize(pCur, (i64*)&n);
  if( sqlite3BtreeFlags(pCur) & BTREE_INTKEY ){
    char zBuf2[60];
    sqlite3_snprintf(sizeof(zBuf2),zBuf2, "%llu", n);
    Tcl_AppendResult(interp, zBuf2, 0);
  }else{
    zBuf = sqlite3_malloc( n+1 );
    rc = sqlite3BtreeKey(pCur, 0, n, zBuf);
    if( rc ){
      Tcl_AppendResult(interp, errorName(rc), 0);
      return TCL_ERROR;
    }
    zBuf[n] = 0;
    Tcl_AppendResult(interp, zBuf, 0);
    sqlite3_free(zBuf);
  }
  return SQLITE_OK;
}

/*
** Usage:   btree_data ID ?N?
**
................................................................................
  }
  pCur = sqlite3TextToPtr(argv[1]);
  if( argc==2 ){
    sqlite3BtreeDataSize(pCur, &n);
  }else{
    n = atoi(argv[2]);
  }
  zBuf = sqlite3_malloc( n+1 );
  rc = sqlite3BtreeData(pCur, 0, n, zBuf);
  if( rc ){
    Tcl_AppendResult(interp, errorName(rc), 0);
    free(zBuf);
    return TCL_ERROR;
  }
  zBuf[n] = 0;
  Tcl_AppendResult(interp, zBuf, 0);
  sqlite3_free(zBuf);
  return SQLITE_OK;
}

/*
** Usage:   btree_fetch_key ID AMT
**
** Use the sqlite3BtreeKeyFetch() routine to get AMT bytes of the key.

**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** Code for testing the the SQLite library in a multithreaded environment.
**
** $Id: test4.c,v 1.17 2006/02/23 21:43:56 drh Exp $
*/
#include "sqliteInt.h"
#include "tcl.h"
#include "os.h"
#if defined(OS_UNIX) && OS_UNIX==1 && defined(THREADSAFE) && THREADSAFE==1
#include <stdlib.h>
#include <string.h>
................................................................................
  if( i<0 ) return TCL_ERROR;
  if( threadset[i].busy ){
    Tcl_AppendResult(interp, "thread ", argv[1], " is already running", 0);
    return TCL_ERROR;
  }
  threadset[i].busy = 1;
  sqliteFree(threadset[i].zFilename);
  threadset[i].zFilename = sqliteStrDup(argv[2]);
  threadset[i].opnum = 1;
  threadset[i].completed = 0;
  rc = pthread_create(&x, 0, thread_main, &threadset[i]);
  if( rc ){
    Tcl_AppendResult(interp, "failed to create the thread", 0);
    sqliteFree(threadset[i].zFilename);
    threadset[i].busy = 0;
................................................................................
  if( !threadset[i].busy ){
    Tcl_AppendResult(interp, "no such thread", 0);
    return TCL_ERROR;
  }
  thread_wait(&threadset[i]);
  threadset[i].xOp = do_compile;
  sqliteFree(threadset[i].zArg);
  threadset[i].zArg = sqliteStrDup(argv[2]);
  threadset[i].opnum++;
  return TCL_OK;
}

/*
** This procedure runs in the thread to step the virtual machine.
*/

**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** Code for testing the the SQLite library in a multithreaded environment.
**
** $Id: test4.c,v 1.18 2007/08/16 04:30:40 drh Exp $
*/
#include "sqliteInt.h"
#include "tcl.h"
#include "os.h"
#if defined(OS_UNIX) && OS_UNIX==1 && defined(THREADSAFE) && THREADSAFE==1
#include <stdlib.h>
#include <string.h>
................................................................................
  if( i<0 ) return TCL_ERROR;
  if( threadset[i].busy ){
    Tcl_AppendResult(interp, "thread ", argv[1], " is already running", 0);
    return TCL_ERROR;
  }
  threadset[i].busy = 1;
  sqliteFree(threadset[i].zFilename);
  threadset[i].zFilename = sqlite3StrDup(argv[2]);
  threadset[i].opnum = 1;
  threadset[i].completed = 0;
  rc = pthread_create(&x, 0, thread_main, &threadset[i]);
  if( rc ){
    Tcl_AppendResult(interp, "failed to create the thread", 0);
    sqliteFree(threadset[i].zFilename);
    threadset[i].busy = 0;
................................................................................
  if( !threadset[i].busy ){
    Tcl_AppendResult(interp, "no such thread", 0);
    return TCL_ERROR;
  }
  thread_wait(&threadset[i]);
  threadset[i].xOp = do_compile;
  sqliteFree(threadset[i].zArg);
  threadset[i].zArg = sqlite3StrDup(argv[2]);
  threadset[i].opnum++;
  return TCL_OK;
}

/*
** This procedure runs in the thread to step the virtual machine.
*/

*************************************************************************
** Code for testing the utf.c module in SQLite.  This code
** is not included in the SQLite library.  It is used for automated
** testing of the SQLite library. Specifically, the code in this file
** is used for testing the SQLite routines for converting between
** the various supported unicode encodings.
**
** $Id: test5.c,v 1.16 2007/05/08 20:37:40 drh Exp $
*/
#include "sqliteInt.h"
#include "vdbeInt.h"
#include "os.h"         /* to get SQLITE_BIGENDIAN */
#include "tcl.h"
#include <stdlib.h>
#include <string.h>
................................................................................
  if( !enc_to ) return TCL_ERROR;

  pVal = sqlite3ValueNew();

  if( enc_from==SQLITE_UTF8 ){
    z = Tcl_GetString(objv[1]);
    if( objc==5 ){
      z = sqliteStrDup(z);
    }
    sqlite3ValueSetStr(pVal, -1, z, enc_from, xDel);
  }else{
    z = (char*)Tcl_GetByteArrayFromObj(objv[1], &len);
    if( objc==5 ){
      char *zTmp = z;
      z = sqliteMalloc(len);
      memcpy(z, zTmp, len);
    }
    sqlite3ValueSetStr(pVal, -1, z, enc_from, xDel);
  }

  z = (char *)sqlite3ValueText(pVal, enc_to);
  len = sqlite3ValueBytes(pVal, enc_to) + (enc_to==SQLITE_UTF8?1:2);

*************************************************************************
** Code for testing the utf.c module in SQLite.  This code
** is not included in the SQLite library.  It is used for automated
** testing of the SQLite library. Specifically, the code in this file
** is used for testing the SQLite routines for converting between
** the various supported unicode encodings.
**
** $Id: test5.c,v 1.17 2007/08/16 04:30:40 drh Exp $
*/
#include "sqliteInt.h"
#include "vdbeInt.h"
#include "os.h"         /* to get SQLITE_BIGENDIAN */
#include "tcl.h"
#include <stdlib.h>
#include <string.h>
................................................................................
  if( !enc_to ) return TCL_ERROR;

  pVal = sqlite3ValueNew();

  if( enc_from==SQLITE_UTF8 ){
    z = Tcl_GetString(objv[1]);
    if( objc==5 ){
      z = sqlite3StrDup(z);
    }
    sqlite3ValueSetStr(pVal, -1, z, enc_from, xDel);
  }else{
    z = (char*)Tcl_GetByteArrayFromObj(objv[1], &len);
    if( objc==5 ){
      char *zTmp = z;
      z = sqlite3_malloc(len);
      memcpy(z, zTmp, len);
    }
    sqlite3ValueSetStr(pVal, -1, z, enc_from, xDel);
  }

  z = (char *)sqlite3ValueText(pVal, enc_to);
  len = sqlite3ValueBytes(pVal, enc_to) + (enc_to==SQLITE_UTF8?1:2);

          rc = sqlite3OsWrite(
              pFile->pRealFile, pWrite->zBuf, pWrite->nBuf, pWrite->iOffset
          );
        }else{
          rc = sqlite3OsTruncate(pFile->pRealFile, pWrite->iOffset);
        }
        *ppPtr = pWrite->pNext;
        sqliteFree(pWrite);
        break;
      }
      case 2: {               /* Do nothing */
        ppPtr = &pWrite->pNext;
        break;
      }
      case 3: {               /* Trash sectors */
        u8 *zGarbage;
        sqlite3_int64 iFirst = (pWrite->iOffset%g.iSectorSize);
        sqlite3_int64 iLast = (pWrite->iOffset+pWrite->nBuf-1)%g.iSectorSize;

        zGarbage = sqliteMalloc(g.iSectorSize);
        if( zGarbage ){
          sqlite3_int64 i;
          for(i=iFirst; rc==SQLITE_OK && i<=iLast; i++){
            sqlite3Randomness(g.iSectorSize, zGarbage); 
            rc = sqlite3OsWrite(
              pFile->pRealFile, i*g.iSectorSize, zGarbage, g.iSectorSize
            );
          }
          sqliteFree(zGarbage);
        }else{
          rc = SQLITE_NOMEM;
        }

        ppPtr = &pWrite->pNext;
        break;
      }
................................................................................
  const u8 *zBuf,
  int nBuf
){
  WriteBuffer *pNew;

  assert((zBuf && nBuf) || (!nBuf && !zBuf));

  pNew = (WriteBuffer *)sqliteMalloc(sizeof(WriteBuffer) + nBuf);
  pNew->iOffset = iOffset;
  pNew->nBuf = nBuf;
  pNew->pFile = (CrashFile *)pFile;
  if( zBuf ){
    pNew->zBuf = (u8 *)&pNew[1];
    memcpy(pNew->zBuf, zBuf, nBuf);
  }
................................................................................
  sqlite3_file *pFile,
  int flags,
  int *pOutFlags
){
  CrashFile *pWrapper = (CrashFile *)pFile;
  int rc = SQLITE_NOMEM;
  sqlite3_file *pReal;
  pReal = (sqlite3_file *)sqliteMalloc(pVfs->szOsFile);
  if( pReal ){
    pWrapper->pMethod = &CrashFileVtab;
    pWrapper->zName = zName;
    rc = pVfs->xOpen(pVfs->pAppData, zName, pReal, flags, pOutFlags);
    if( rc==SQLITE_OK ){
      pWrapper->pRealFile = pFile;
    }else{
      sqliteFree(pReal);
    }
  }
  return rc;
}

int sqlite3CrashFileWrap(
  sqlite3_file *pFile,
  const char *zName,
  sqlite3_file **ppWrapper
){
  CrashFile *pWrapper;
  pWrapper = (CrashFile *)sqliteMalloc(sizeof(CrashFile)+strlen(zName)+1);
  if( !pWrapper ){
    return SQLITE_NOMEM;
  }

  pWrapper->pMethod = &CrashFileVtab;
  pWrapper->pRealFile = pFile;
  pWrapper->zName = &pWrapper[1];

          rc = sqlite3OsWrite(
              pFile->pRealFile, pWrite->zBuf, pWrite->nBuf, pWrite->iOffset
          );
        }else{
          rc = sqlite3OsTruncate(pFile->pRealFile, pWrite->iOffset);
        }
        *ppPtr = pWrite->pNext;
        sqlite3_free(pWrite);
        break;
      }
      case 2: {               /* Do nothing */
        ppPtr = &pWrite->pNext;
        break;
      }
      case 3: {               /* Trash sectors */
        u8 *zGarbage;
        sqlite3_int64 iFirst = (pWrite->iOffset%g.iSectorSize);
        sqlite3_int64 iLast = (pWrite->iOffset+pWrite->nBuf-1)%g.iSectorSize;

        zGarbage = sqlite3_malloc(g.iSectorSize);
        if( zGarbage ){
          sqlite3_int64 i;
          for(i=iFirst; rc==SQLITE_OK && i<=iLast; i++){
            sqlite3Randomness(g.iSectorSize, zGarbage); 
            rc = sqlite3OsWrite(
              pFile->pRealFile, i*g.iSectorSize, zGarbage, g.iSectorSize
            );
          }
          sqlite3_free(zGarbage);
        }else{
          rc = SQLITE_NOMEM;
        }

        ppPtr = &pWrite->pNext;
        break;
      }
................................................................................
  const u8 *zBuf,
  int nBuf
){
  WriteBuffer *pNew;

  assert((zBuf && nBuf) || (!nBuf && !zBuf));

  pNew = (WriteBuffer *)sqlite3_malloc(sizeof(WriteBuffer) + nBuf);
  pNew->iOffset = iOffset;
  pNew->nBuf = nBuf;
  pNew->pFile = (CrashFile *)pFile;
  if( zBuf ){
    pNew->zBuf = (u8 *)&pNew[1];
    memcpy(pNew->zBuf, zBuf, nBuf);
  }
................................................................................
  sqlite3_file *pFile,
  int flags,
  int *pOutFlags
){
  CrashFile *pWrapper = (CrashFile *)pFile;
  int rc = SQLITE_NOMEM;
  sqlite3_file *pReal;
  pReal = (sqlite3_file *)sqlite3_malloc(pVfs->szOsFile);
  if( pReal ){
    pWrapper->pMethod = &CrashFileVtab;
    pWrapper->zName = zName;
    rc = pVfs->xOpen(pVfs->pAppData, zName, pReal, flags, pOutFlags);
    if( rc==SQLITE_OK ){
      pWrapper->pRealFile = pFile;
    }else{
      sqlite3_free(pReal);
    }
  }
  return rc;
}

int sqlite3CrashFileWrap(
  sqlite3_file *pFile,
  const char *zName,
  sqlite3_file **ppWrapper
){
  CrashFile *pWrapper;
  pWrapper = (CrashFile *)sqlite3_malloc(sizeof(CrashFile)+strlen(zName)+1);
  if( !pWrapper ){
    return SQLITE_NOMEM;
  }

  pWrapper->pMethod = &CrashFileVtab;
  pWrapper->pRealFile = pFile;
  pWrapper->zName = &pWrapper[1];

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** Code for testing the client/server version of the SQLite library.
** Derived from test4.c.
**
** $Id: test7.c,v 1.4 2006/03/22 22:10:08 drh Exp $
*/
#include "sqliteInt.h"
#include "tcl.h"
#include "os.h"

/*
** This test only works on UNIX with a THREADSAFE build that includes
................................................................................
  if( i<0 ) return TCL_ERROR;
  if( threadset[i].busy ){
    Tcl_AppendResult(interp, "thread ", argv[1], " is already running", 0);
    return TCL_ERROR;
  }
  threadset[i].busy = 1;
  sqliteFree(threadset[i].zFilename);
  threadset[i].zFilename = sqliteStrDup(argv[2]);
  threadset[i].opnum = 1;
  threadset[i].completed = 0;
  rc = pthread_create(&x, 0, client_main, &threadset[i]);
  if( rc ){
    Tcl_AppendResult(interp, "failed to create the thread", 0);
    sqliteFree(threadset[i].zFilename);
    threadset[i].busy = 0;
................................................................................
  if( !threadset[i].busy ){
    Tcl_AppendResult(interp, "no such thread", 0);
    return TCL_ERROR;
  }
  client_wait(&threadset[i]);
  threadset[i].xOp = do_compile;
  sqliteFree(threadset[i].zArg);
  threadset[i].zArg = sqliteStrDup(argv[2]);
  threadset[i].opnum++;
  return TCL_OK;
}

/*
** This procedure runs in the thread to step the virtual machine.
*/

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** Code for testing the client/server version of the SQLite library.
** Derived from test4.c.
**
** $Id: test7.c,v 1.5 2007/08/16 04:30:40 drh Exp $
*/
#include "sqliteInt.h"
#include "tcl.h"
#include "os.h"

/*
** This test only works on UNIX with a THREADSAFE build that includes
................................................................................
  if( i<0 ) return TCL_ERROR;
  if( threadset[i].busy ){
    Tcl_AppendResult(interp, "thread ", argv[1], " is already running", 0);
    return TCL_ERROR;
  }
  threadset[i].busy = 1;
  sqliteFree(threadset[i].zFilename);
  threadset[i].zFilename = sqlite3StrDup(argv[2]);
  threadset[i].opnum = 1;
  threadset[i].completed = 0;
  rc = pthread_create(&x, 0, client_main, &threadset[i]);
  if( rc ){
    Tcl_AppendResult(interp, "failed to create the thread", 0);
    sqliteFree(threadset[i].zFilename);
    threadset[i].busy = 0;
................................................................................
  if( !threadset[i].busy ){
    Tcl_AppendResult(interp, "no such thread", 0);
    return TCL_ERROR;
  }
  client_wait(&threadset[i]);
  threadset[i].xOp = do_compile;
  sqliteFree(threadset[i].zArg);
  threadset[i].zArg = sqlite3StrDup(argv[2]);
  threadset[i].opnum++;
  return TCL_OK;
}

/*
** This procedure runs in the thread to step the virtual machine.
*/

**    May you share freely, never taking more than you give.
**
*************************************************************************
** Code for testing the virtual table interfaces.  This code
** is not included in the SQLite library.  It is used for automated
** testing of the SQLite library.
**
** $Id: test8.c,v 1.48 2007/07/20 00:35:59 drh Exp $
*/
#include "sqliteInt.h"
#include "tcl.h"
#include "os.h"
#include <stdlib.h>
#include <string.h>

................................................................................

/*
** Retrieve the column names for the table named zTab via database
** connection db. SQLITE_OK is returned on success, or an sqlite error
** code otherwise.
**
** If successful, the number of columns is written to *pnCol. *paCol is
** set to point at sqliteMalloc()'d space containing the array of
** nCol column names. The caller is responsible for calling sqliteFree
** on *paCol.
*/
static int getColumnNames(
  sqlite3 *db, 
  const char *zTab,
  char ***paCol, 
  int *pnCol
................................................................................
  int rc = SQLITE_OK;
  int nCol = 0;

  /* Prepare the statement "SELECT * FROM <tbl>". The column names
  ** of the result set of the compiled SELECT will be the same as
  ** the column names of table <tbl>.
  */
  zSql = sqlite3MPrintf("SELECT * FROM %Q", zTab);
  if( !zSql ){
    rc = SQLITE_NOMEM;
    goto out;
  }
  rc = sqlite3_prepare(db, zSql, -1, &pStmt, 0);
  sqliteFree(zSql);

  if( rc==SQLITE_OK ){
    int ii;
    int nBytes;
    char *zSpace;
    nCol = sqlite3_column_count(pStmt);

................................................................................
    /* Figure out how much space to allocate for the array of column names 
    ** (including space for the strings themselves). Then allocate it.
    */
    nBytes = sizeof(char *) * nCol;
    for(ii=0; ii<nCol; ii++){
      nBytes += (strlen(sqlite3_column_name(pStmt, ii)) + 1);
    }
    aCol = (char **)sqliteMalloc(nBytes);
    if( !aCol ){
      rc = SQLITE_NOMEM;
      goto out;
    }

    /* Copy the column names into the allocated space and set up the
    ** pointers in the aCol[] array.
................................................................................
){
  sqlite3_stmt *pStmt = 0;
  int *aIndex = 0;
  int rc;
  char *zSql;

  /* Allocate space for the index array */
  aIndex = (int *)sqliteMalloc(sizeof(int) * nCol);
  if( !aIndex ){
    rc = SQLITE_NOMEM;
    goto get_index_array_out;
  }

  /* Compile an sqlite pragma to loop through all indices on table zTab */
  zSql = sqlite3MPrintf("PRAGMA index_list(%s)", zTab);
  if( !zSql ){
    rc = SQLITE_NOMEM;
    goto get_index_array_out;
  }
  rc = sqlite3_prepare(db, zSql, -1, &pStmt, 0);
  sqliteFree(zSql);

  /* For each index, figure out the left-most column and set the 
  ** corresponding entry in aIndex[] to 1.
  */
  while( pStmt && sqlite3_step(pStmt)==SQLITE_ROW ){
    const char *zIdx = (const char *)sqlite3_column_text(pStmt, 1);
    sqlite3_stmt *pStmt2 = 0;
    zSql = sqlite3MPrintf("PRAGMA index_info(%s)", zIdx);
    if( !zSql ){
      rc = SQLITE_NOMEM;
      goto get_index_array_out;
    }
    rc = sqlite3_prepare(db, zSql, -1, &pStmt2, 0);
    sqliteFree(zSql);
    if( pStmt2 && sqlite3_step(pStmt2)==SQLITE_ROW ){
      int cid = sqlite3_column_int(pStmt2, 1);
      assert( cid>=0 && cid<nCol );
      aIndex[cid] = 1;
    }
    if( pStmt2 ){
      rc = sqlite3_finalize(pStmt2);
................................................................................
  if( pStmt ){
    int rc2 = sqlite3_finalize(pStmt);
    if( rc==SQLITE_OK ){
      rc = rc2;
    }
  }
  if( rc!=SQLITE_OK ){
    sqliteFree(aIndex);
    aIndex = 0;
  }
  *paIndex = aIndex;
  return rc;
}

/*
................................................................................

/*
** This function frees all runtime structures associated with the virtual
** table pVtab.
*/
static int echoDestructor(sqlite3_vtab *pVtab){
  echo_vtab *p = (echo_vtab*)pVtab;
  sqliteFree(p->aIndex);
  sqliteFree(p->aCol);
  sqliteFree(p->zThis);
  sqliteFree(p->zTableName);
  sqliteFree(p->zLogName);
  sqliteFree(p);
  return 0;
}

/*
** This function is called to do the work of the xConnect() method -
** to allocate the required in-memory structures for a newly connected
** virtual table.
................................................................................
  sqlite3_vtab **ppVtab,
  char **pzErr
){
  int i;
  echo_vtab *pVtab;

  /* Allocate the sqlite3_vtab/echo_vtab structure itself */
  pVtab = sqliteMalloc( sizeof(*pVtab) );
  if( !pVtab ){
    return SQLITE_NOMEM;
  }
  pVtab->interp = (Tcl_Interp *)pAux;
  pVtab->db = db;

  /* Allocate echo_vtab.zThis */
................................................................................

  /* Allocate echo_vtab.zTableName */
  if( argc>3 ){
    pVtab->zTableName = sqlite3MPrintf("%s", argv[3]);
    dequoteString(pVtab->zTableName);
    if( pVtab->zTableName && pVtab->zTableName[0]=='*' ){
      char *z = sqlite3MPrintf("%s%s", argv[2], &(pVtab->zTableName[1]));
      sqliteFree(pVtab->zTableName);
      pVtab->zTableName = z;
      pVtab->isPattern = 1;
    }
    if( !pVtab->zTableName ){
      echoDestructor((sqlite3_vtab *)pVtab);
      return SQLITE_NOMEM;
    }
................................................................................
  */
  if( rc==SQLITE_OK && argc==5 ){
    char *zSql;
    echo_vtab *pVtab = *(echo_vtab **)ppVtab;
    pVtab->zLogName = sqlite3MPrintf("%s", argv[4]);
    zSql = sqlite3MPrintf("CREATE TABLE %Q(logmsg)", pVtab->zLogName);
    rc = sqlite3_exec(db, zSql, 0, 0, 0);
    sqliteFree(zSql);
  }

  return rc;
}

/* 
** Echo virtual table module xConnect method.
................................................................................
  appendToEchoModule(((echo_vtab *)pVtab)->interp, "xDestroy");

  /* Drop the "log" table, if one exists (see echoCreate() for details) */
  if( p && p->zLogName ){
    char *zSql;
    zSql = sqlite3MPrintf("DROP TABLE %Q", p->zLogName);
    rc = sqlite3_exec(p->db, zSql, 0, 0, 0);
    sqliteFree(zSql);
  }

  if( rc==SQLITE_OK ){
    rc = echoDestructor(pVtab);
  }
  return rc;
}

/* 
** Echo virtual table module xOpen method.
*/
static int echoOpen(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor){
  echo_cursor *pCur;
  pCur = sqliteMalloc(sizeof(echo_cursor));
  *ppCursor = (sqlite3_vtab_cursor *)pCur;
  return (pCur ? SQLITE_OK : SQLITE_NOMEM);
}

/* 
** Echo virtual table module xClose method.
*/
static int echoClose(sqlite3_vtab_cursor *cur){
  int rc;
  echo_cursor *pCur = (echo_cursor *)cur;
  sqlite3_stmt *pStmt = pCur->pStmt;
  pCur->pStmt = 0;
  sqliteFree(pCur);
  rc = sqlite3_finalize(pStmt);
  return rc;
}

/*
** Return non-zero if the cursor does not currently point to a valid record
** (i.e if the scan has finished), or zero otherwise.
................................................................................

  if( p->isPattern ){
    int nThis = strlen(p->zThis);
    char *zSql = sqlite3MPrintf("ALTER TABLE %s RENAME TO %s%s", 
        p->zTableName, zNewName, &p->zTableName[nThis]
    );
    rc = sqlite3_exec(p->db, zSql, 0, 0, 0);
    sqliteFree(zSql);
  }

  return rc;
}

/*
** A virtual table module that merely "echos" the contents of another

**    May you share freely, never taking more than you give.
**
*************************************************************************
** Code for testing the virtual table interfaces.  This code
** is not included in the SQLite library.  It is used for automated
** testing of the SQLite library.
**
** $Id: test8.c,v 1.49 2007/08/16 04:30:40 drh Exp $
*/
#include "sqliteInt.h"
#include "tcl.h"
#include "os.h"
#include <stdlib.h>
#include <string.h>

................................................................................

/*
** Retrieve the column names for the table named zTab via database
** connection db. SQLITE_OK is returned on success, or an sqlite error
** code otherwise.
**
** If successful, the number of columns is written to *pnCol. *paCol is
** set to point at sqlite3_malloc()'d space containing the array of
** nCol column names. The caller is responsible for calling sqlite3_free
** on *paCol.
*/
static int getColumnNames(
  sqlite3 *db, 
  const char *zTab,
  char ***paCol, 
  int *pnCol
................................................................................
  int rc = SQLITE_OK;
  int nCol = 0;

  /* Prepare the statement "SELECT * FROM <tbl>". The column names
  ** of the result set of the compiled SELECT will be the same as
  ** the column names of table <tbl>.
  */
  zSql = sqlite3_mprintf("SELECT * FROM %Q", zTab);
  if( !zSql ){
    rc = SQLITE_NOMEM;
    goto out;
  }
  rc = sqlite3_prepare(db, zSql, -1, &pStmt, 0);
  sqlite3_free(zSql);

  if( rc==SQLITE_OK ){
    int ii;
    int nBytes;
    char *zSpace;
    nCol = sqlite3_column_count(pStmt);

................................................................................
    /* Figure out how much space to allocate for the array of column names 
    ** (including space for the strings themselves). Then allocate it.
    */
    nBytes = sizeof(char *) * nCol;
    for(ii=0; ii<nCol; ii++){
      nBytes += (strlen(sqlite3_column_name(pStmt, ii)) + 1);
    }
    aCol = (char **)sqlite3_malloc(nBytes);
    if( !aCol ){
      rc = SQLITE_NOMEM;
      goto out;
    }

    /* Copy the column names into the allocated space and set up the
    ** pointers in the aCol[] array.
................................................................................
){
  sqlite3_stmt *pStmt = 0;
  int *aIndex = 0;
  int rc;
  char *zSql;

  /* Allocate space for the index array */
  aIndex = (int *)sqlite3_malloc(sizeof(int) * nCol);
  if( !aIndex ){
    rc = SQLITE_NOMEM;
    goto get_index_array_out;
  }

  /* Compile an sqlite pragma to loop through all indices on table zTab */
  zSql = sqlite3MPrintf("PRAGMA index_list(%s)", zTab);
  if( !zSql ){
    rc = SQLITE_NOMEM;
    goto get_index_array_out;
  }
  rc = sqlite3_prepare(db, zSql, -1, &pStmt, 0);
  sqlite3_free(zSql);

  /* For each index, figure out the left-most column and set the 
  ** corresponding entry in aIndex[] to 1.
  */
  while( pStmt && sqlite3_step(pStmt)==SQLITE_ROW ){
    const char *zIdx = (const char *)sqlite3_column_text(pStmt, 1);
    sqlite3_stmt *pStmt2 = 0;
    zSql = sqlite3MPrintf("PRAGMA index_info(%s)", zIdx);
    if( !zSql ){
      rc = SQLITE_NOMEM;
      goto get_index_array_out;
    }
    rc = sqlite3_prepare(db, zSql, -1, &pStmt2, 0);
    sqlite3_free(zSql);
    if( pStmt2 && sqlite3_step(pStmt2)==SQLITE_ROW ){
      int cid = sqlite3_column_int(pStmt2, 1);
      assert( cid>=0 && cid<nCol );
      aIndex[cid] = 1;
    }
    if( pStmt2 ){
      rc = sqlite3_finalize(pStmt2);
................................................................................
  if( pStmt ){
    int rc2 = sqlite3_finalize(pStmt);
    if( rc==SQLITE_OK ){
      rc = rc2;
    }
  }
  if( rc!=SQLITE_OK ){
    sqlite3_free(aIndex);
    aIndex = 0;
  }
  *paIndex = aIndex;
  return rc;
}

/*
................................................................................

/*
** This function frees all runtime structures associated with the virtual
** table pVtab.
*/
static int echoDestructor(sqlite3_vtab *pVtab){
  echo_vtab *p = (echo_vtab*)pVtab;
  sqlite3_free(p->aIndex);
  sqlite3_free(p->aCol);
  sqlite3_free(p->zThis);
  sqlite3_free(p->zTableName);
  sqlite3_free(p->zLogName);
  sqlite3_free(p);
  return 0;
}

/*
** This function is called to do the work of the xConnect() method -
** to allocate the required in-memory structures for a newly connected
** virtual table.
................................................................................
  sqlite3_vtab **ppVtab,
  char **pzErr
){
  int i;
  echo_vtab *pVtab;

  /* Allocate the sqlite3_vtab/echo_vtab structure itself */
  pVtab = sqlite3_malloc( sizeof(*pVtab) );
  if( !pVtab ){
    return SQLITE_NOMEM;
  }
  pVtab->interp = (Tcl_Interp *)pAux;
  pVtab->db = db;

  /* Allocate echo_vtab.zThis */
................................................................................

  /* Allocate echo_vtab.zTableName */
  if( argc>3 ){
    pVtab->zTableName = sqlite3MPrintf("%s", argv[3]);
    dequoteString(pVtab->zTableName);
    if( pVtab->zTableName && pVtab->zTableName[0]=='*' ){
      char *z = sqlite3MPrintf("%s%s", argv[2], &(pVtab->zTableName[1]));
      sqlite3_free(pVtab->zTableName);
      pVtab->zTableName = z;
      pVtab->isPattern = 1;
    }
    if( !pVtab->zTableName ){
      echoDestructor((sqlite3_vtab *)pVtab);
      return SQLITE_NOMEM;
    }
................................................................................
  */
  if( rc==SQLITE_OK && argc==5 ){
    char *zSql;
    echo_vtab *pVtab = *(echo_vtab **)ppVtab;
    pVtab->zLogName = sqlite3MPrintf("%s", argv[4]);
    zSql = sqlite3MPrintf("CREATE TABLE %Q(logmsg)", pVtab->zLogName);
    rc = sqlite3_exec(db, zSql, 0, 0, 0);
    sqlite3_free(zSql);
  }

  return rc;
}

/* 
** Echo virtual table module xConnect method.
................................................................................
  appendToEchoModule(((echo_vtab *)pVtab)->interp, "xDestroy");

  /* Drop the "log" table, if one exists (see echoCreate() for details) */
  if( p && p->zLogName ){
    char *zSql;
    zSql = sqlite3MPrintf("DROP TABLE %Q", p->zLogName);
    rc = sqlite3_exec(p->db, zSql, 0, 0, 0);
    sqlite3_free(zSql);
  }

  if( rc==SQLITE_OK ){
    rc = echoDestructor(pVtab);
  }
  return rc;
}

/* 
** Echo virtual table module xOpen method.
*/
static int echoOpen(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor){
  echo_cursor *pCur;
  pCur = sqlite3_malloc(sizeof(echo_cursor));
  *ppCursor = (sqlite3_vtab_cursor *)pCur;
  return (pCur ? SQLITE_OK : SQLITE_NOMEM);
}

/* 
** Echo virtual table module xClose method.
*/
static int echoClose(sqlite3_vtab_cursor *cur){
  int rc;
  echo_cursor *pCur = (echo_cursor *)cur;
  sqlite3_stmt *pStmt = pCur->pStmt;
  pCur->pStmt = 0;
  sqlite3_free(pCur);
  rc = sqlite3_finalize(pStmt);
  return rc;
}

/*
** Return non-zero if the cursor does not currently point to a valid record
** (i.e if the scan has finished), or zero otherwise.
................................................................................

  if( p->isPattern ){
    int nThis = strlen(p->zThis);
    char *zSql = sqlite3MPrintf("ALTER TABLE %s RENAME TO %s%s", 
        p->zTableName, zNewName, &p->zTableName[nThis]
    );
    rc = sqlite3_exec(p->db, zSql, 0, 0, 0);
    sqlite3_free(zSql);
  }

  return rc;
}

/*
** A virtual table module that merely "echos" the contents of another

**
** ASYNC_OPENEXCLUSIVE:
**     iOffset -> Value of "delflag".
**     nByte   -> Number of bytes of zBuf points to (file name).
**
**
** For an ASYNC_WRITE operation, zBuf points to the data to write to the file. 
** This space is sqliteMalloc()d along with the AsyncWrite structure in a
** single blob, so is deleted when sqliteFree() is called on the parent 
** structure.
*/
struct AsyncWrite {
  AsyncFile *pFile;   /* File to write data to or sync */
  int op;             /* One of ASYNC_xxx etc. */
  i64 iOffset;        /* See above */
  int nByte;          /* See above */
................................................................................
  int nName;           /* Number of characters in zName */
  OsFile *pBaseRead;   /* Read handle to the underlying Os file */
  OsFile *pBaseWrite;  /* Write handle to the underlying Os file */
};

/*
** Add an entry to the end of the global write-op list. pWrite should point 
** to an AsyncWrite structure allocated using sqlite3OsMalloc().  The writer
** thread will call sqlite3OsFree() to free the structure after the specified
** operation has been completed.
**
** Once an AsyncWrite structure has been added to the list, it becomes the
** property of the writer thread and must not be read or modified by the
** caller.  
*/
static void addAsyncWrite(AsyncWrite *pWrite){
................................................................................
  int nByte,
  const char *zByte
){
  AsyncWrite *p;
  if( op!=ASYNC_CLOSE && async.ioError ){
    return async.ioError;
  }
  p = sqlite3OsMalloc(sizeof(AsyncWrite) + (zByte?nByte:0));
  if( !p ){
    return SQLITE_NOMEM;
  }
  p->op = op;
  p->iOffset = iOffset;
  p->nByte = nByte;
  p->pFile = pFile;
................................................................................
    if( rc!=SQLITE_OK ){
      goto error_out;
    }
  }

  n = strlen(zName);
  for(i=n-1; i>=0 && zName[i]!='/'; i--){}
  p = (AsyncFile *)sqlite3OsMalloc(sizeof(AsyncFile) + n - i);
  if( !p ){
    rc = SQLITE_NOMEM;
    goto error_out;
  }
  memset(p, 0, sizeof(AsyncFile));
  p->zName = (char*)&p[1];
  strcpy(p->zName, &zName[i+1]);
................................................................................
  int rc = asyncOpenFile(z, ppFile, 0, 0);
  if( rc==SQLITE_OK ){
    AsyncFile *pFile = (AsyncFile *)(*ppFile);
    int nByte = strlen(z)+1;
    i64 i = (i64)(delFlag);
    rc = addNewAsyncWrite(pFile, ASYNC_OPENEXCLUSIVE, i, nByte, z);
    if( rc!=SQLITE_OK ){
      sqlite3OsFree(pFile);
      *ppFile = 0;
    }
  }
  if( rc==SQLITE_OK ){
    incrOpenFileCount();
  }
  return rc;
................................................................................
        rc = sqlite3OsTruncate(pBase, p->iOffset);
        break;

      case ASYNC_CLOSE:
        ASYNC_TRACE(("CLOSE %s\n", p->pFile->zName));
        sqlite3OsClose(&p->pFile->pBaseWrite);
        sqlite3OsClose(&p->pFile->pBaseRead);
        sqlite3OsFree(p->pFile);
        break;

      case ASYNC_OPENDIRECTORY:
        assert( pBase );
        ASYNC_TRACE(("OPENDIR %s\n", p->zBuf));
        sqlite3OsOpenDirectory(pBase, p->zBuf);
        break;
................................................................................
      holdingMutex = 1;
    }
    /* ASYNC_TRACE(("UNLINK %p\n", p)); */
    if( p==async.pQueueLast ){
      async.pQueueLast = 0;
    }
    async.pQueueFirst = p->pNext;
    sqlite3OsFree(p);
    assert( holdingMutex );

    /* An IO error has occured. We cannot report the error back to the
    ** connection that requested the I/O since the error happened 
    ** asynchronously.  The connection has already moved on.  There 
    ** really is nobody to report the error to.
    **

**
** ASYNC_OPENEXCLUSIVE:
**     iOffset -> Value of "delflag".
**     nByte   -> Number of bytes of zBuf points to (file name).
**
**
** For an ASYNC_WRITE operation, zBuf points to the data to write to the file. 
** This space is sqlite3_malloc()d along with the AsyncWrite structure in a
** single blob, so is deleted when sqlite3_free() is called on the parent 
** structure.
*/
struct AsyncWrite {
  AsyncFile *pFile;   /* File to write data to or sync */
  int op;             /* One of ASYNC_xxx etc. */
  i64 iOffset;        /* See above */
  int nByte;          /* See above */
................................................................................
  int nName;           /* Number of characters in zName */
  OsFile *pBaseRead;   /* Read handle to the underlying Os file */
  OsFile *pBaseWrite;  /* Write handle to the underlying Os file */
};

/*
** Add an entry to the end of the global write-op list. pWrite should point 
** to an AsyncWrite structure allocated using sqlite3_malloc().  The writer
** thread will call sqlite3_free() to free the structure after the specified
** operation has been completed.
**
** Once an AsyncWrite structure has been added to the list, it becomes the
** property of the writer thread and must not be read or modified by the
** caller.  
*/
static void addAsyncWrite(AsyncWrite *pWrite){
................................................................................
  int nByte,
  const char *zByte
){
  AsyncWrite *p;
  if( op!=ASYNC_CLOSE && async.ioError ){
    return async.ioError;
  }
  p = sqlite3_malloc(sizeof(AsyncWrite) + (zByte?nByte:0));
  if( !p ){
    return SQLITE_NOMEM;
  }
  p->op = op;
  p->iOffset = iOffset;
  p->nByte = nByte;
  p->pFile = pFile;
................................................................................
    if( rc!=SQLITE_OK ){
      goto error_out;
    }
  }

  n = strlen(zName);
  for(i=n-1; i>=0 && zName[i]!='/'; i--){}
  p = (AsyncFile *)sqlite3_malloc(sizeof(AsyncFile) + n - i);
  if( !p ){
    rc = SQLITE_NOMEM;
    goto error_out;
  }
  memset(p, 0, sizeof(AsyncFile));
  p->zName = (char*)&p[1];
  strcpy(p->zName, &zName[i+1]);
................................................................................
  int rc = asyncOpenFile(z, ppFile, 0, 0);
  if( rc==SQLITE_OK ){
    AsyncFile *pFile = (AsyncFile *)(*ppFile);
    int nByte = strlen(z)+1;
    i64 i = (i64)(delFlag);
    rc = addNewAsyncWrite(pFile, ASYNC_OPENEXCLUSIVE, i, nByte, z);
    if( rc!=SQLITE_OK ){
      sqlite3_free(pFile);
      *ppFile = 0;
    }
  }
  if( rc==SQLITE_OK ){
    incrOpenFileCount();
  }
  return rc;
................................................................................
        rc = sqlite3OsTruncate(pBase, p->iOffset);
        break;

      case ASYNC_CLOSE:
        ASYNC_TRACE(("CLOSE %s\n", p->pFile->zName));
        sqlite3OsClose(&p->pFile->pBaseWrite);
        sqlite3OsClose(&p->pFile->pBaseRead);
        sqlite3_free(p->pFile);
        break;

      case ASYNC_OPENDIRECTORY:
        assert( pBase );
        ASYNC_TRACE(("OPENDIR %s\n", p->zBuf));
        sqlite3OsOpenDirectory(pBase, p->zBuf);
        break;
................................................................................
      holdingMutex = 1;
    }
    /* ASYNC_TRACE(("UNLINK %p\n", p)); */
    if( p==async.pQueueLast ){
      async.pQueueLast = 0;
    }
    async.pQueueFirst = p->pNext;
    sqlite3_free(p);
    assert( holdingMutex );

    /* An IO error has occured. We cannot report the error back to the
    ** connection that requested the I/O since the error happened 
    ** asynchronously.  The connection has already moved on.  There 
    ** really is nobody to report the error to.
    **

** implements TCL commands for reading and writing the binary
** database files and displaying the content of those files as
** hexadecimal.  We could, in theory, use the built-in "binary"
** command of TCL to do a lot of this, but there are some issues
** with historical versions of the "binary" command.  So it seems
** easier and safer to build our own mechanism.
**
** $Id: test_hexio.c,v 1.3 2007/05/10 17:23:12 drh Exp $
*/
#include "sqliteInt.h"
#include "tcl.h"
#include <stdlib.h>
#include <string.h>
#include <assert.h>

................................................................................
  if( objc!=4 ){
    Tcl_WrongNumArgs(interp, 1, objv, "FILENAME OFFSET AMT");
    return TCL_ERROR;
  }
  if( Tcl_GetIntFromObj(interp, objv[2], &offset) ) return TCL_ERROR;
  if( Tcl_GetIntFromObj(interp, objv[3], &amt) ) return TCL_ERROR;
  zFile = Tcl_GetString(objv[1]);
  zBuf = malloc( amt*2+1 );
  if( zBuf==0 ){
    return TCL_ERROR;
  }
  in = fopen(zFile, "r");
  if( in==0 ){
    Tcl_AppendResult(interp, "cannot open input file ", zFile, 0);
    return TCL_ERROR;
................................................................................
  got = fread(zBuf, 1, amt, in);
  fclose(in);
  if( got<0 ){
    got = 0;
  }
  binToHex(zBuf, got);
  Tcl_AppendResult(interp, zBuf, 0);
  free(zBuf);
  return TCL_OK;
}


/*
** Usage:   hexio_write  FILENAME  OFFSET  DATA
**
................................................................................
  if( objc!=4 ){
    Tcl_WrongNumArgs(interp, 1, objv, "FILENAME OFFSET HEXDATA");
    return TCL_ERROR;
  }
  if( Tcl_GetIntFromObj(interp, objv[2], &offset) ) return TCL_ERROR;
  zFile = Tcl_GetString(objv[1]);
  zIn = (const unsigned char *)Tcl_GetStringFromObj(objv[3], &nIn);
  aOut = malloc( nIn/2 );
  if( aOut==0 ){
    return TCL_ERROR;
  }
  nOut = hexToBin(zIn, nIn, aOut);
  out = fopen(zFile, "r+");
  if( out==0 ){
    Tcl_AppendResult(interp, "cannot open output file ", zFile, 0);
    return TCL_ERROR;
  }
  fseek(out, offset, SEEK_SET);
  written = fwrite(aOut, 1, nOut, out);
  free(aOut);
  fclose(out);
  Tcl_SetObjResult(interp, Tcl_NewIntObj(written));
  return TCL_OK;
}

/*
** USAGE:   hexio_get_int   HEXDATA
................................................................................
  unsigned char aNum[4];

  if( objc!=2 ){
    Tcl_WrongNumArgs(interp, 1, objv, "HEXDATA");
    return TCL_ERROR;
  }
  zIn = (const unsigned char *)Tcl_GetStringFromObj(objv[1], &nIn);
  aOut = malloc( nIn/2 );
  if( aOut==0 ){
    return TCL_ERROR;
  }
  nOut = hexToBin(zIn, nIn, aOut);
  if( nOut>=4 ){
    memcpy(aNum, aOut, 4);
  }else{
    memset(aNum, 0, sizeof(aNum));
    memcpy(&aNum[4-nOut], aOut, nOut);
  }
  free(aOut);
  val = (aNum[0]<<24) | (aNum[1]<<16) | (aNum[2]<<8) | aNum[3];
  Tcl_SetObjResult(interp, Tcl_NewIntObj(val));
  return TCL_OK;
}


/*

** implements TCL commands for reading and writing the binary
** database files and displaying the content of those files as
** hexadecimal.  We could, in theory, use the built-in "binary"
** command of TCL to do a lot of this, but there are some issues
** with historical versions of the "binary" command.  So it seems
** easier and safer to build our own mechanism.
**
** $Id: test_hexio.c,v 1.4 2007/08/16 04:30:40 drh Exp $
*/
#include "sqliteInt.h"
#include "tcl.h"
#include <stdlib.h>
#include <string.h>
#include <assert.h>

................................................................................
  if( objc!=4 ){
    Tcl_WrongNumArgs(interp, 1, objv, "FILENAME OFFSET AMT");
    return TCL_ERROR;
  }
  if( Tcl_GetIntFromObj(interp, objv[2], &offset) ) return TCL_ERROR;
  if( Tcl_GetIntFromObj(interp, objv[3], &amt) ) return TCL_ERROR;
  zFile = Tcl_GetString(objv[1]);
  zBuf = sqlite3_malloc( amt*2+1 );
  if( zBuf==0 ){
    return TCL_ERROR;
  }
  in = fopen(zFile, "r");
  if( in==0 ){
    Tcl_AppendResult(interp, "cannot open input file ", zFile, 0);
    return TCL_ERROR;
................................................................................
  got = fread(zBuf, 1, amt, in);
  fclose(in);
  if( got<0 ){
    got = 0;
  }
  binToHex(zBuf, got);
  Tcl_AppendResult(interp, zBuf, 0);
  sqlite3_free(zBuf);
  return TCL_OK;
}


/*
** Usage:   hexio_write  FILENAME  OFFSET  DATA
**
................................................................................
  if( objc!=4 ){
    Tcl_WrongNumArgs(interp, 1, objv, "FILENAME OFFSET HEXDATA");
    return TCL_ERROR;
  }
  if( Tcl_GetIntFromObj(interp, objv[2], &offset) ) return TCL_ERROR;
  zFile = Tcl_GetString(objv[1]);
  zIn = (const unsigned char *)Tcl_GetStringFromObj(objv[3], &nIn);
  aOut = sqlite3_malloc( nIn/2 );
  if( aOut==0 ){
    return TCL_ERROR;
  }
  nOut = hexToBin(zIn, nIn, aOut);
  out = fopen(zFile, "r+");
  if( out==0 ){
    Tcl_AppendResult(interp, "cannot open output file ", zFile, 0);
    return TCL_ERROR;
  }
  fseek(out, offset, SEEK_SET);
  written = fwrite(aOut, 1, nOut, out);
  sqlite3_free(aOut);
  fclose(out);
  Tcl_SetObjResult(interp, Tcl_NewIntObj(written));
  return TCL_OK;
}

/*
** USAGE:   hexio_get_int   HEXDATA
................................................................................
  unsigned char aNum[4];

  if( objc!=2 ){
    Tcl_WrongNumArgs(interp, 1, objv, "HEXDATA");
    return TCL_ERROR;
  }
  zIn = (const unsigned char *)Tcl_GetStringFromObj(objv[1], &nIn);
  aOut = sqlite3_malloc( nIn/2 );
  if( aOut==0 ){
    return TCL_ERROR;
  }
  nOut = hexToBin(zIn, nIn, aOut);
  if( nOut>=4 ){
    memcpy(aNum, aOut, 4);
  }else{
    memset(aNum, 0, sizeof(aNum));
    memcpy(&aNum[4-nOut], aOut, nOut);
  }
  sqlite3_free(aOut);
  val = (aNum[0]<<24) | (aNum[1]<<16) | (aNum[2]<<8) | aNum[3];
  Tcl_SetObjResult(interp, Tcl_NewIntObj(val));
  return TCL_OK;
}


/*

**    May you share freely, never taking more than you give.
**
*************************************************************************
** Code for testing the virtual table interfaces.  This code
** is not included in the SQLite library.  It is used for automated
** testing of the SQLite library.
**
** $Id: test_schema.c,v 1.12 2007/06/27 16:26:07 danielk1977 Exp $
*/

/* The code in this file defines a sqlite3 virtual-table module that
** provides a read-only view of the current database schema. There is one
** row in the schema table for each column in the database schema.
*/
#define SCHEMA \
................................................................................
/* If SQLITE_TEST is defined this code is preprocessed for use as part
** of the sqlite test binary "testfixture". Otherwise it is preprocessed
** to be compiled into an sqlite dynamic extension.
*/
#ifdef SQLITE_TEST
  #include "sqliteInt.h"
  #include "tcl.h"
  #define MALLOC(x) sqliteMallocRaw(x) 
  #define FREE(x)   sqliteFree(x)
#else
  #include "sqlite3ext.h"
  SQLITE_EXTENSION_INIT1
  #define MALLOC(x) malloc(x) 
  #define FREE(x)   free(x)
#endif

#include <stdlib.h>
#include <string.h>
#include <assert.h>

typedef struct schema_vtab schema_vtab;
................................................................................
  int rowid;
};

/*
** Table destructor for the schema module.
*/
static int schemaDestroy(sqlite3_vtab *pVtab){
  FREE(pVtab);
  return 0;
}

/*
** Table constructor for the schema module.
*/
static int schemaCreate(
................................................................................
  sqlite3 *db,
  void *pAux,
  int argc, const char *const*argv,
  sqlite3_vtab **ppVtab,
  char **pzErr
){
  int rc = SQLITE_NOMEM;
  schema_vtab *pVtab = MALLOC(sizeof(schema_vtab));
  if( pVtab ){
    memset(pVtab, 0, sizeof(schema_vtab));
    pVtab->db = db;
#ifndef SQLITE_OMIT_VIRTUALTABLE
    rc = sqlite3_declare_vtab(db, SCHEMA);
#endif
  }
................................................................................

/*
** Open a new cursor on the schema table.
*/
static int schemaOpen(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor){
  int rc = SQLITE_NOMEM;
  schema_cursor *pCur;
  pCur = MALLOC(sizeof(schema_cursor));
  if( pCur ){
    memset(pCur, 0, sizeof(schema_cursor));
    *ppCursor = (sqlite3_vtab_cursor *)pCur;
    rc = SQLITE_OK;
  }
  return rc;
}
................................................................................
** Close a schema table cursor.
*/
static int schemaClose(sqlite3_vtab_cursor *cur){
  schema_cursor *pCur = (schema_cursor *)cur;
  sqlite3_finalize(pCur->pDbList);
  sqlite3_finalize(pCur->pTableList);
  sqlite3_finalize(pCur->pColumnList);
  FREE(pCur);
  return SQLITE_OK;
}

/*
** Retrieve a column of data.
*/
static int schemaColumn(sqlite3_vtab_cursor *cur, sqlite3_context *ctx, int i){

**    May you share freely, never taking more than you give.
**
*************************************************************************
** Code for testing the virtual table interfaces.  This code
** is not included in the SQLite library.  It is used for automated
** testing of the SQLite library.
**
** $Id: test_schema.c,v 1.13 2007/08/16 04:30:40 drh Exp $
*/

/* The code in this file defines a sqlite3 virtual-table module that
** provides a read-only view of the current database schema. There is one
** row in the schema table for each column in the database schema.
*/
#define SCHEMA \
................................................................................
/* If SQLITE_TEST is defined this code is preprocessed for use as part
** of the sqlite test binary "testfixture". Otherwise it is preprocessed
** to be compiled into an sqlite dynamic extension.
*/
#ifdef SQLITE_TEST
  #include "sqliteInt.h"
  #include "tcl.h"


#else
  #include "sqlite3ext.h"
  SQLITE_EXTENSION_INIT1


#endif

#include <stdlib.h>
#include <string.h>
#include <assert.h>

typedef struct schema_vtab schema_vtab;
................................................................................
  int rowid;
};

/*
** Table destructor for the schema module.
*/
static int schemaDestroy(sqlite3_vtab *pVtab){
  sqlite3_free(pVtab);
  return 0;
}

/*
** Table constructor for the schema module.
*/
static int schemaCreate(
................................................................................
  sqlite3 *db,
  void *pAux,
  int argc, const char *const*argv,
  sqlite3_vtab **ppVtab,
  char **pzErr
){
  int rc = SQLITE_NOMEM;
  schema_vtab *pVtab = sqlite3_malloc(sizeof(schema_vtab));
  if( pVtab ){
    memset(pVtab, 0, sizeof(schema_vtab));
    pVtab->db = db;
#ifndef SQLITE_OMIT_VIRTUALTABLE
    rc = sqlite3_declare_vtab(db, SCHEMA);
#endif
  }
................................................................................

/*
** Open a new cursor on the schema table.
*/
static int schemaOpen(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor){
  int rc = SQLITE_NOMEM;
  schema_cursor *pCur;
  pCur = sqlite3_malloc(sizeof(schema_cursor));
  if( pCur ){
    memset(pCur, 0, sizeof(schema_cursor));
    *ppCursor = (sqlite3_vtab_cursor *)pCur;
    rc = SQLITE_OK;
  }
  return rc;
}
................................................................................
** Close a schema table cursor.
*/
static int schemaClose(sqlite3_vtab_cursor *cur){
  schema_cursor *pCur = (schema_cursor *)cur;
  sqlite3_finalize(pCur->pDbList);
  sqlite3_finalize(pCur->pTableList);
  sqlite3_finalize(pCur->pColumnList);
  sqlite3_free(pCur);
  return SQLITE_OK;
}

/*
** Retrieve a column of data.
*/
static int schemaColumn(sqlite3_vtab_cursor *cur, sqlite3_context *ctx, int i){

** Code for testing the virtual table interfaces.  This code
** is not included in the SQLite library.  It is used for automated
** testing of the SQLite library.
**
** The emphasis of this file is a virtual table that provides
** access to TCL variables.
**
** $Id: test_tclvar.c,v 1.11 2007/06/27 16:26:07 danielk1977 Exp $
*/
#include "sqliteInt.h"
#include "tcl.h"
#include "os.h"
#include <stdlib.h>
#include <string.h>

................................................................................
  int argc, const char *const*argv,
  sqlite3_vtab **ppVtab,
  char **pzErr
){
  tclvar_vtab *pVtab;
  static const char zSchema[] = 
     "CREATE TABLE whatever(name TEXT, arrayname TEXT, value TEXT)";
  pVtab = sqliteMalloc( sizeof(*pVtab) );
  if( pVtab==0 ) return SQLITE_NOMEM;
  *ppVtab = &pVtab->base;
  pVtab->interp = (Tcl_Interp *)pAux;
  sqlite3_declare_vtab(db, zSchema);
  return SQLITE_OK;
}
/* Note that for this virtual table, the xCreate and xConnect
** methods are identical. */

static int tclvarDisconnect(sqlite3_vtab *pVtab){
  sqliteFree(pVtab);
  return SQLITE_OK;
}
/* The xDisconnect and xDestroy methods are also the same */

/*
** Open a new tclvar cursor.
*/
static int tclvarOpen(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor){
  tclvar_cursor *pCur;
  pCur = sqliteMalloc(sizeof(tclvar_cursor));
  *ppCursor = &pCur->base;
  return SQLITE_OK;
}

/*
** Close a tclvar cursor.
*/
................................................................................
  tclvar_cursor *pCur = (tclvar_cursor *)cur;
  if( pCur->pList1 ){
    Tcl_DecrRefCount(pCur->pList1);
  }
  if( pCur->pList2 ){
    Tcl_DecrRefCount(pCur->pList2);
  }
  sqliteFree(pCur);
  return SQLITE_OK;
}

/*
** Returns 1 if data is ready, or 0 if not.
*/
static int next2(Tcl_Interp *interp, tclvar_cursor *pCur, Tcl_Obj *pObj){

** Code for testing the virtual table interfaces.  This code
** is not included in the SQLite library.  It is used for automated
** testing of the SQLite library.
**
** The emphasis of this file is a virtual table that provides
** access to TCL variables.
**
** $Id: test_tclvar.c,v 1.12 2007/08/16 04:30:40 drh Exp $
*/
#include "sqliteInt.h"
#include "tcl.h"
#include "os.h"
#include <stdlib.h>
#include <string.h>

................................................................................
  int argc, const char *const*argv,
  sqlite3_vtab **ppVtab,
  char **pzErr
){
  tclvar_vtab *pVtab;
  static const char zSchema[] = 
     "CREATE TABLE whatever(name TEXT, arrayname TEXT, value TEXT)";
  pVtab = sqlite3_malloc( sizeof(*pVtab) );
  if( pVtab==0 ) return SQLITE_NOMEM;
  *ppVtab = &pVtab->base;
  pVtab->interp = (Tcl_Interp *)pAux;
  sqlite3_declare_vtab(db, zSchema);
  return SQLITE_OK;
}
/* Note that for this virtual table, the xCreate and xConnect
** methods are identical. */

static int tclvarDisconnect(sqlite3_vtab *pVtab){
  sqlite3_free(pVtab);
  return SQLITE_OK;
}
/* The xDisconnect and xDestroy methods are also the same */

/*
** Open a new tclvar cursor.
*/
static int tclvarOpen(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor){
  tclvar_cursor *pCur;
  pCur = sqlite3_malloc(sizeof(tclvar_cursor));
  *ppCursor = &pCur->base;
  return SQLITE_OK;
}

/*
** Close a tclvar cursor.
*/
................................................................................
  tclvar_cursor *pCur = (tclvar_cursor *)cur;
  if( pCur->pList1 ){
    Tcl_DecrRefCount(pCur->pList1);
  }
  if( pCur->pList2 ){
    Tcl_DecrRefCount(pCur->pList2);
  }
  sqlite3_free(pCur);
  return SQLITE_OK;
}

/*
** Returns 1 if data is ready, or 0 if not.
*/
static int next2(Tcl_Interp *interp, tclvar_cursor *pCur, Tcl_Obj *pObj){

*************************************************************************
** An tokenizer for SQL
**
** This file contains C code that splits an SQL input string up into
** individual tokens and sends those tokens one-by-one over to the
** parser for analysis.
**
** $Id: tokenize.c,v 1.131 2007/07/23 19:31:17 drh Exp $
*/
#include "sqliteInt.h"
#include "os.h"
#include <ctype.h>
#include <stdlib.h>

/*
................................................................................
  return getToken(z, tokenType);
}

/*
** Run the parser on the given SQL string.  The parser structure is
** passed in.  An SQLITE_ status code is returned.  If an error occurs
** and pzErrMsg!=NULL then an error message might be written into 
** memory obtained from malloc() and *pzErrMsg made to point to that
** error message.  Or maybe not.
*/
int sqlite3RunParser(Parse *pParse, const char *zSql, char **pzErrMsg){
  int nErr = 0;
  int i;
  void *pEngine;
  int tokenType;
................................................................................
  sqlite3 *db = pParse->db;

  if( db->activeVdbeCnt==0 ){
    db->u1.isInterrupted = 0;
  }
  pParse->rc = SQLITE_OK;
  i = 0;
  pEngine = sqlite3ParserAlloc((void*(*)(size_t))sqlite3MallocX);
  if( pEngine==0 ){
    return SQLITE_NOMEM;
  }
  assert( pParse->sLastToken.dyn==0 );
  assert( pParse->pNewTable==0 );
  assert( pParse->pNewTrigger==0 );
  assert( pParse->nVar==0 );
  assert( pParse->nVarExpr==0 );
  assert( pParse->nVarExprAlloc==0 );
  assert( pParse->apVarExpr==0 );
  pParse->zTail = pParse->zSql = zSql;
  while( !sqlite3MallocFailed() && zSql[i]!=0 ){
    assert( i>=0 );
    pParse->sLastToken.z = (u8*)&zSql[i];
    assert( pParse->sLastToken.dyn==0 );
    pParse->sLastToken.n = getToken((unsigned char*)&zSql[i],&tokenType);
    i += pParse->sLastToken.n;
    if( i>SQLITE_MAX_SQL_LENGTH ){
      pParse->rc = SQLITE_TOOBIG;
................................................................................
          sqlite3SetString(pzErrMsg, "interrupt", (char*)0);
          goto abort_parse;
        }
        break;
      }
      case TK_ILLEGAL: {
        if( pzErrMsg ){
          sqliteFree(*pzErrMsg);
          *pzErrMsg = sqlite3MPrintf("unrecognized token: \"%T\"",
                          &pParse->sLastToken);
        }
        nErr++;
        goto abort_parse;
      }
      case TK_SEMI: {
................................................................................
  if( zSql[i]==0 && nErr==0 && pParse->rc==SQLITE_OK ){
    if( lastTokenParsed!=TK_SEMI ){
      sqlite3Parser(pEngine, TK_SEMI, pParse->sLastToken, pParse);
      pParse->zTail = &zSql[i];
    }
    sqlite3Parser(pEngine, 0, pParse->sLastToken, pParse);
  }
  sqlite3ParserFree(pEngine, sqlite3FreeX);
  if( sqlite3MallocFailed() ){
    pParse->rc = SQLITE_NOMEM;
  }
  if( pParse->rc!=SQLITE_OK && pParse->rc!=SQLITE_DONE && pParse->zErrMsg==0 ){
    sqlite3SetString(&pParse->zErrMsg, sqlite3ErrStr(pParse->rc), (char*)0);
  }
  if( pParse->zErrMsg ){
    if( pzErrMsg && *pzErrMsg==0 ){
      *pzErrMsg = pParse->zErrMsg;
    }else{
      sqliteFree(pParse->zErrMsg);
    }
    pParse->zErrMsg = 0;
    if( !nErr ) nErr++;
  }
  if( pParse->pVdbe && pParse->nErr>0 && pParse->nested==0 ){
    sqlite3VdbeDelete(pParse->pVdbe);
    pParse->pVdbe = 0;
  }
#ifndef SQLITE_OMIT_SHARED_CACHE
  if( pParse->nested==0 ){
    sqliteFree(pParse->aTableLock);
    pParse->aTableLock = 0;
    pParse->nTableLock = 0;
  }
#endif

  if( !IN_DECLARE_VTAB ){
    /* If the pParse->declareVtab flag is set, do not delete any table 
................................................................................
    ** structure built up in pParse->pNewTable. The calling code (see vtab.c)
    ** will take responsibility for freeing the Table structure.
    */
    sqlite3DeleteTable(pParse->pNewTable);
  }

  sqlite3DeleteTrigger(pParse->pNewTrigger);
  sqliteFree(pParse->apVarExpr);
  if( nErr>0 && (pParse->rc==SQLITE_OK || pParse->rc==SQLITE_DONE) ){
    pParse->rc = SQLITE_ERROR;
  }
  return nErr;
}

*************************************************************************
** An tokenizer for SQL
**
** This file contains C code that splits an SQL input string up into
** individual tokens and sends those tokens one-by-one over to the
** parser for analysis.
**
** $Id: tokenize.c,v 1.132 2007/08/16 04:30:40 drh Exp $
*/
#include "sqliteInt.h"
#include "os.h"
#include <ctype.h>
#include <stdlib.h>

/*
................................................................................
  return getToken(z, tokenType);
}

/*
** Run the parser on the given SQL string.  The parser structure is
** passed in.  An SQLITE_ status code is returned.  If an error occurs
** and pzErrMsg!=NULL then an error message might be written into 
** memory obtained from sqlite3_malloc() and *pzErrMsg made to point to that
** error message.  Or maybe not.
*/
int sqlite3RunParser(Parse *pParse, const char *zSql, char **pzErrMsg){
  int nErr = 0;
  int i;
  void *pEngine;
  int tokenType;
................................................................................
  sqlite3 *db = pParse->db;

  if( db->activeVdbeCnt==0 ){
    db->u1.isInterrupted = 0;
  }
  pParse->rc = SQLITE_OK;
  i = 0;
  pEngine = sqlite3ParserAlloc((void*(*)(size_t))sqlite3_malloc);
  if( pEngine==0 ){
    return SQLITE_NOMEM;
  }
  assert( pParse->sLastToken.dyn==0 );
  assert( pParse->pNewTable==0 );
  assert( pParse->pNewTrigger==0 );
  assert( pParse->nVar==0 );
  assert( pParse->nVarExpr==0 );
  assert( pParse->nVarExprAlloc==0 );
  assert( pParse->apVarExpr==0 );
  pParse->zTail = pParse->zSql = zSql;
  while( !db->mallocFailed && zSql[i]!=0 ){
    assert( i>=0 );
    pParse->sLastToken.z = (u8*)&zSql[i];
    assert( pParse->sLastToken.dyn==0 );
    pParse->sLastToken.n = getToken((unsigned char*)&zSql[i],&tokenType);
    i += pParse->sLastToken.n;
    if( i>SQLITE_MAX_SQL_LENGTH ){
      pParse->rc = SQLITE_TOOBIG;
................................................................................
          sqlite3SetString(pzErrMsg, "interrupt", (char*)0);
          goto abort_parse;
        }
        break;
      }
      case TK_ILLEGAL: {
        if( pzErrMsg ){
          sqlite3_free(*pzErrMsg);
          *pzErrMsg = sqlite3MPrintf("unrecognized token: \"%T\"",
                          &pParse->sLastToken);
        }
        nErr++;
        goto abort_parse;
      }
      case TK_SEMI: {
................................................................................
  if( zSql[i]==0 && nErr==0 && pParse->rc==SQLITE_OK ){
    if( lastTokenParsed!=TK_SEMI ){
      sqlite3Parser(pEngine, TK_SEMI, pParse->sLastToken, pParse);
      pParse->zTail = &zSql[i];
    }
    sqlite3Parser(pEngine, 0, pParse->sLastToken, pParse);
  }
  sqlite3ParserFree(pEngine, sqlite3_free);
  if( db->mallocFailed ){
    pParse->rc = SQLITE_NOMEM;
  }
  if( pParse->rc!=SQLITE_OK && pParse->rc!=SQLITE_DONE && pParse->zErrMsg==0 ){
    sqlite3SetString(&pParse->zErrMsg, sqlite3ErrStr(pParse->rc), (char*)0);
  }
  if( pParse->zErrMsg ){
    if( pzErrMsg && *pzErrMsg==0 ){
      *pzErrMsg = pParse->zErrMsg;
    }else{
      sqlite3_free(pParse->zErrMsg);
    }
    pParse->zErrMsg = 0;
    if( !nErr ) nErr++;
  }
  if( pParse->pVdbe && pParse->nErr>0 && pParse->nested==0 ){
    sqlite3VdbeDelete(pParse->pVdbe);
    pParse->pVdbe = 0;
  }
#ifndef SQLITE_OMIT_SHARED_CACHE
  if( pParse->nested==0 ){
    sqlite3_free(pParse->aTableLock);
    pParse->aTableLock = 0;
    pParse->nTableLock = 0;
  }
#endif

  if( !IN_DECLARE_VTAB ){
    /* If the pParse->declareVtab flag is set, do not delete any table 
................................................................................
    ** structure built up in pParse->pNewTable. The calling code (see vtab.c)
    ** will take responsibility for freeing the Table structure.
    */
    sqlite3DeleteTable(pParse->pNewTable);
  }

  sqlite3DeleteTrigger(pParse->pNewTrigger);
  sqlite3_free(pParse->apVarExpr);
  if( nErr>0 && (pParse->rc==SQLITE_OK || pParse->rc==SQLITE_DONE) ){
    pParse->rc = SQLITE_ERROR;
  }
  return nErr;
}

** Delete a linked list of TriggerStep structures.
*/
void sqlite3DeleteTriggerStep(TriggerStep *pTriggerStep){
  while( pTriggerStep ){
    TriggerStep * pTmp = pTriggerStep;
    pTriggerStep = pTriggerStep->pNext;

    if( pTmp->target.dyn ) sqliteFree((char*)pTmp->target.z);
    sqlite3ExprDelete(pTmp->pWhere);
    sqlite3ExprListDelete(pTmp->pExprList);
    sqlite3SelectDelete(pTmp->pSelect);
    sqlite3IdListDelete(pTmp->pIdList);

    sqliteFree(pTmp);
  }
}

/*
** This is called by the parser when it sees a CREATE TRIGGER statement
** up to the point of the BEGIN before the trigger actions.  A Trigger
** structure is generated based on the information available and stored
................................................................................
  }

  /* If the trigger name was unqualified, and the table is a temp table,
  ** then set iDb to 1 to create the trigger in the temporary database.
  ** If sqlite3SrcListLookup() returns 0, indicating the table does not
  ** exist, the error is caught by the block below.
  */
  if( !pTableName || sqlite3MallocFailed() ){
    goto trigger_cleanup;
  }
  pTab = sqlite3SrcListLookup(pParse, pTableName);
  if( pName2->n==0 && pTab && pTab->pSchema==db->aDb[1].pSchema ){
    iDb = 1;
  }

  /* Ensure the table name matches database name and that the table exists */
  if( sqlite3MallocFailed() ) goto trigger_cleanup;
  assert( pTableName->nSrc==1 );
  if( sqlite3FixInit(&sFix, pParse, iDb, "trigger", pName) && 
      sqlite3FixSrcList(&sFix, pTableName) ){
    goto trigger_cleanup;
  }
  pTab = sqlite3SrcListLookup(pParse, pTableName);
  if( !pTab ){
................................................................................
  if( IsVirtual(pTab) ){
    sqlite3ErrorMsg(pParse, "cannot create triggers on virtual tables");
    goto trigger_cleanup;
  }

  /* Check that the trigger name is not reserved and that no trigger of the
  ** specified name exists */
  zName = sqlite3NameFromToken(pName);
  if( !zName || SQLITE_OK!=sqlite3CheckObjectName(pParse, zName) ){
    goto trigger_cleanup;
  }
  if( sqlite3HashFind(&(db->aDb[iDb].pSchema->trigHash), zName,strlen(zName)) ){
    if( !noErr ){
      sqlite3ErrorMsg(pParse, "trigger %T already exists", pName);
    }
................................................................................
  ** elsewhere.
  */
  if (tr_tm == TK_INSTEAD){
    tr_tm = TK_BEFORE;
  }

  /* Build the Trigger object */
  pTrigger = (Trigger*)sqliteMalloc(sizeof(Trigger));
  if( pTrigger==0 ) goto trigger_cleanup;
  pTrigger->name = zName;
  zName = 0;
  pTrigger->table = sqliteStrDup(pTableName->a[0].zName);
  pTrigger->pSchema = db->aDb[iDb].pSchema;
  pTrigger->pTabSchema = pTab->pSchema;
  pTrigger->op = op;
  pTrigger->tr_tm = tr_tm==TK_BEFORE ? TRIGGER_BEFORE : TRIGGER_AFTER;
  pTrigger->pWhen = sqlite3ExprDup(pWhen);
  pTrigger->pColumns = sqlite3IdListDup(pColumns);
  sqlite3TokenCopy(&pTrigger->nameToken,pName);
  assert( pParse->pNewTrigger==0 );
  pParse->pNewTrigger = pTrigger;

trigger_cleanup:
  sqliteFree(zName);
  sqlite3SrcListDelete(pTableName);
  sqlite3IdListDelete(pColumns);
  sqlite3ExprDelete(pWhen);
  if( !pParse->pNewTrigger ){
    sqlite3DeleteTrigger(pTrigger);
  }else{
    assert( pParse->pNewTrigger==pTrigger );
................................................................................
  if( db->init.busy ){
    int n;
    Table *pTab;
    Trigger *pDel;
    pDel = sqlite3HashInsert(&db->aDb[iDb].pSchema->trigHash, 
                     pTrig->name, strlen(pTrig->name), pTrig);
    if( pDel ){
      assert( sqlite3MallocFailed() && pDel==pTrig );
      goto triggerfinish_cleanup;
    }
    n = strlen(pTrig->table) + 1;
    pTab = sqlite3HashFind(&pTrig->pTabSchema->tblHash, pTrig->table, n);
    assert( pTab!=0 );
    pTrig->pNext = pTab->pTrigger;
    pTab->pTrigger = pTrig;
................................................................................
  assert( !pParse->pNewTrigger );
  sqlite3DeleteTriggerStep(pStepList);
}

/*
** Make a copy of all components of the given trigger step.  This has
** the effect of copying all Expr.token.z values into memory obtained
** from sqliteMalloc().  As initially created, the Expr.token.z values
** all point to the input string that was fed to the parser.  But that
** string is ephemeral - it will go away as soon as the sqlite3_exec()
** call that started the parser exits.  This routine makes a persistent
** copy of all the Expr.token.z strings so that the TriggerStep structure
** will be valid even after the sqlite3_exec() call returns.
*/
static void sqlitePersistTriggerStep(TriggerStep *p){
  if( p->target.z ){
    p->target.z = (u8*)sqliteStrNDup((char*)p->target.z, p->target.n);
    p->target.dyn = 1;
  }
  if( p->pSelect ){
    Select *pNew = sqlite3SelectDup(p->pSelect);
    sqlite3SelectDelete(p->pSelect);
    p->pSelect = pNew;
  }
  if( p->pWhere ){
    Expr *pNew = sqlite3ExprDup(p->pWhere);
    sqlite3ExprDelete(p->pWhere);
    p->pWhere = pNew;
  }
  if( p->pExprList ){
    ExprList *pNew = sqlite3ExprListDup(p->pExprList);
    sqlite3ExprListDelete(p->pExprList);
    p->pExprList = pNew;
  }
  if( p->pIdList ){
    IdList *pNew = sqlite3IdListDup(p->pIdList);
    sqlite3IdListDelete(p->pIdList);
    p->pIdList = pNew;
  }
}

/*
** Turn a SELECT statement (that the pSelect parameter points to) into
** a trigger step.  Return a pointer to a TriggerStep structure.
**
** The parser calls this routine when it finds a SELECT statement in
** body of a TRIGGER.  
*/
TriggerStep *sqlite3TriggerSelectStep(Select *pSelect){
  TriggerStep *pTriggerStep = sqliteMalloc(sizeof(TriggerStep));
  if( pTriggerStep==0 ) {
    sqlite3SelectDelete(pSelect);
    return 0;
  }

  pTriggerStep->op = TK_SELECT;
  pTriggerStep->pSelect = pSelect;
  pTriggerStep->orconf = OE_Default;
  sqlitePersistTriggerStep(pTriggerStep);

  return pTriggerStep;
}

/*
** Build a trigger step out of an INSERT statement.  Return a pointer
** to the new trigger step.
**
** The parser calls this routine when it sees an INSERT inside the
** body of a trigger.
*/
TriggerStep *sqlite3TriggerInsertStep(

  Token *pTableName,  /* Name of the table into which we insert */
  IdList *pColumn,    /* List of columns in pTableName to insert into */
  ExprList *pEList,   /* The VALUE clause: a list of values to be inserted */
  Select *pSelect,    /* A SELECT statement that supplies values */
  int orconf          /* The conflict algorithm (OE_Abort, OE_Replace, etc.) */
){
  TriggerStep *pTriggerStep = sqliteMalloc(sizeof(TriggerStep));

  assert(pEList == 0 || pSelect == 0);
  assert(pEList != 0 || pSelect != 0);

  if( pTriggerStep ){
    pTriggerStep->op = TK_INSERT;
    pTriggerStep->pSelect = pSelect;
    pTriggerStep->target  = *pTableName;
    pTriggerStep->pIdList = pColumn;
    pTriggerStep->pExprList = pEList;
    pTriggerStep->orconf = orconf;
    sqlitePersistTriggerStep(pTriggerStep);
  }else{
    sqlite3IdListDelete(pColumn);
    sqlite3ExprListDelete(pEList);
    sqlite3SelectDup(pSelect);
  }

  return pTriggerStep;
}

/*
** Construct a trigger step that implements an UPDATE statement and return
** a pointer to that trigger step.  The parser calls this routine when it
** sees an UPDATE statement inside the body of a CREATE TRIGGER.
*/
TriggerStep *sqlite3TriggerUpdateStep(

  Token *pTableName,   /* Name of the table to be updated */
  ExprList *pEList,    /* The SET clause: list of column and new values */
  Expr *pWhere,        /* The WHERE clause */
  int orconf           /* The conflict algorithm. (OE_Abort, OE_Ignore, etc) */
){
  TriggerStep *pTriggerStep = sqliteMalloc(sizeof(TriggerStep));
  if( pTriggerStep==0 ){
     sqlite3ExprListDelete(pEList);
     sqlite3ExprDelete(pWhere);
     return 0;
  }

  pTriggerStep->op = TK_UPDATE;
  pTriggerStep->target  = *pTableName;
  pTriggerStep->pExprList = pEList;
  pTriggerStep->pWhere = pWhere;
  pTriggerStep->orconf = orconf;
  sqlitePersistTriggerStep(pTriggerStep);

  return pTriggerStep;
}

/*
** Construct a trigger step that implements a DELETE statement and return
** a pointer to that trigger step.  The parser calls this routine when it
** sees a DELETE statement inside the body of a CREATE TRIGGER.
*/
TriggerStep *sqlite3TriggerDeleteStep(Token *pTableName, Expr *pWhere){




  TriggerStep *pTriggerStep = sqliteMalloc(sizeof(TriggerStep));
  if( pTriggerStep==0 ){
    sqlite3ExprDelete(pWhere);
    return 0;
  }

  pTriggerStep->op = TK_DELETE;
  pTriggerStep->target  = *pTableName;
  pTriggerStep->pWhere = pWhere;
  pTriggerStep->orconf = OE_Default;
  sqlitePersistTriggerStep(pTriggerStep);

  return pTriggerStep;
}

/* 
** Recursively delete a Trigger structure
*/
void sqlite3DeleteTrigger(Trigger *pTrigger){
  if( pTrigger==0 ) return;
  sqlite3DeleteTriggerStep(pTrigger->step_list);
  sqliteFree(pTrigger->name);
  sqliteFree(pTrigger->table);
  sqlite3ExprDelete(pTrigger->pWhen);
  sqlite3IdListDelete(pTrigger->pColumns);
  if( pTrigger->nameToken.dyn ) sqliteFree((char*)pTrigger->nameToken.z);
  sqliteFree(pTrigger);
}

/*
** This function is called to drop a trigger from the database schema. 
**
** This may be called directly from the parser and therefore identifies
** the trigger by name.  The sqlite3DropTriggerPtr() routine does the
................................................................................
  Trigger *pTrigger = 0;
  int i;
  const char *zDb;
  const char *zName;
  int nName;
  sqlite3 *db = pParse->db;

  if( sqlite3MallocFailed() ) goto drop_trigger_cleanup;
  if( SQLITE_OK!=sqlite3ReadSchema(pParse) ){
    goto drop_trigger_cleanup;
  }

  assert( pName->nSrc==1 );
  zDb = pName->a[0].zDatabase;
  zName = pName->a[0].zName;
................................................................................
  SrcList *pSrc;       /* SrcList to be returned */

  iDb = sqlite3SchemaToIndex(pParse->db, pStep->pTrig->pSchema);
  if( iDb==0 || iDb>=2 ){
    assert( iDb<pParse->db->nDb );
    sDb.z = (u8*)pParse->db->aDb[iDb].zName;
    sDb.n = strlen((char*)sDb.z);
    pSrc = sqlite3SrcListAppend(0, &sDb, &pStep->target);
  } else {
    pSrc = sqlite3SrcListAppend(0, &pStep->target, 0);
  }
  return pSrc;
}

/*
** Generate VDBE code for zero or more statements inside the body of a
** trigger.  
................................................................................
  Parse *pParse,            /* The parser context */
  TriggerStep *pStepList,   /* List of statements inside the trigger body */
  int orconfin              /* Conflict algorithm. (OE_Abort, etc) */  
){
  TriggerStep * pTriggerStep = pStepList;
  int orconf;
  Vdbe *v = pParse->pVdbe;


  assert( pTriggerStep!=0 );
  assert( v!=0 );
  sqlite3VdbeAddOp(v, OP_ContextPush, 0, 0);
  VdbeComment((v, "# begin trigger %s", pStepList->pTrig->name));
  while( pTriggerStep ){
    orconf = (orconfin == OE_Default)?pTriggerStep->orconf:orconfin;
    pParse->trigStack->orconf = orconf;
    switch( pTriggerStep->op ){
      case TK_SELECT: {
        Select *ss = sqlite3SelectDup(pTriggerStep->pSelect);
        if( ss ){
          sqlite3SelectResolve(pParse, ss, 0);
          sqlite3Select(pParse, ss, SRT_Discard, 0, 0, 0, 0, 0);
          sqlite3SelectDelete(ss);
        }
        break;
      }
      case TK_UPDATE: {
        SrcList *pSrc;
        pSrc = targetSrcList(pParse, pTriggerStep);
        sqlite3VdbeAddOp(v, OP_ResetCount, 0, 0);
        sqlite3Update(pParse, pSrc,
                sqlite3ExprListDup(pTriggerStep->pExprList), 
                sqlite3ExprDup(pTriggerStep->pWhere), orconf);
        sqlite3VdbeAddOp(v, OP_ResetCount, 1, 0);
        break;
      }
      case TK_INSERT: {
        SrcList *pSrc;
        pSrc = targetSrcList(pParse, pTriggerStep);
        sqlite3VdbeAddOp(v, OP_ResetCount, 0, 0);
        sqlite3Insert(pParse, pSrc,
          sqlite3ExprListDup(pTriggerStep->pExprList), 
          sqlite3SelectDup(pTriggerStep->pSelect), 
          sqlite3IdListDup(pTriggerStep->pIdList), orconf);
        sqlite3VdbeAddOp(v, OP_ResetCount, 1, 0);
        break;
      }
      case TK_DELETE: {
        SrcList *pSrc;
        sqlite3VdbeAddOp(v, OP_ResetCount, 0, 0);
        pSrc = targetSrcList(pParse, pTriggerStep);
        sqlite3DeleteFrom(pParse, pSrc, sqlite3ExprDup(pTriggerStep->pWhere));

        sqlite3VdbeAddOp(v, OP_ResetCount, 1, 0);
        break;
      }
      default:
        assert(0);
    } 
    pTriggerStep = pTriggerStep->pNext;
................................................................................
      trigStackEntry.pNext = pParse->trigStack;
      trigStackEntry.ignoreJump = ignoreJump;
      pParse->trigStack = &trigStackEntry;
      sqlite3AuthContextPush(pParse, &sContext, p->name);

      /* code the WHEN clause */
      endTrigger = sqlite3VdbeMakeLabel(pParse->pVdbe);
      whenExpr = sqlite3ExprDup(p->pWhen);
      if( sqlite3ExprResolveNames(&sNC, whenExpr) ){
        pParse->trigStack = trigStackEntry.pNext;
        sqlite3ExprDelete(whenExpr);
        return 1;
      }
      sqlite3ExprIfFalse(pParse, whenExpr, endTrigger, 1);
      sqlite3ExprDelete(whenExpr);

** Delete a linked list of TriggerStep structures.
*/
void sqlite3DeleteTriggerStep(TriggerStep *pTriggerStep){
  while( pTriggerStep ){
    TriggerStep * pTmp = pTriggerStep;
    pTriggerStep = pTriggerStep->pNext;

    if( pTmp->target.dyn ) sqlite3_free((char*)pTmp->target.z);
    sqlite3ExprDelete(pTmp->pWhere);
    sqlite3ExprListDelete(pTmp->pExprList);
    sqlite3SelectDelete(pTmp->pSelect);
    sqlite3IdListDelete(pTmp->pIdList);

    sqlite3_free(pTmp);
  }
}

/*
** This is called by the parser when it sees a CREATE TRIGGER statement
** up to the point of the BEGIN before the trigger actions.  A Trigger
** structure is generated based on the information available and stored
................................................................................
  }

  /* If the trigger name was unqualified, and the table is a temp table,
  ** then set iDb to 1 to create the trigger in the temporary database.
  ** If sqlite3SrcListLookup() returns 0, indicating the table does not
  ** exist, the error is caught by the block below.
  */
  if( !pTableName || db->mallocFailed ){
    goto trigger_cleanup;
  }
  pTab = sqlite3SrcListLookup(pParse, pTableName);
  if( pName2->n==0 && pTab && pTab->pSchema==db->aDb[1].pSchema ){
    iDb = 1;
  }

  /* Ensure the table name matches database name and that the table exists */
  if( db->mallocFailed ) goto trigger_cleanup;
  assert( pTableName->nSrc==1 );
  if( sqlite3FixInit(&sFix, pParse, iDb, "trigger", pName) && 
      sqlite3FixSrcList(&sFix, pTableName) ){
    goto trigger_cleanup;
  }
  pTab = sqlite3SrcListLookup(pParse, pTableName);
  if( !pTab ){
................................................................................
  if( IsVirtual(pTab) ){
    sqlite3ErrorMsg(pParse, "cannot create triggers on virtual tables");
    goto trigger_cleanup;
  }

  /* Check that the trigger name is not reserved and that no trigger of the
  ** specified name exists */
  zName = sqlite3NameFromToken(db, pName);
  if( !zName || SQLITE_OK!=sqlite3CheckObjectName(pParse, zName) ){
    goto trigger_cleanup;
  }
  if( sqlite3HashFind(&(db->aDb[iDb].pSchema->trigHash), zName,strlen(zName)) ){
    if( !noErr ){
      sqlite3ErrorMsg(pParse, "trigger %T already exists", pName);
    }
................................................................................
  ** elsewhere.
  */
  if (tr_tm == TK_INSTEAD){
    tr_tm = TK_BEFORE;
  }

  /* Build the Trigger object */
  pTrigger = (Trigger*)sqlite3DbMallocZero(db, sizeof(Trigger));
  if( pTrigger==0 ) goto trigger_cleanup;
  pTrigger->name = zName;
  zName = 0;
  pTrigger->table = sqlite3DbStrDup(db, pTableName->a[0].zName);
  pTrigger->pSchema = db->aDb[iDb].pSchema;
  pTrigger->pTabSchema = pTab->pSchema;
  pTrigger->op = op;
  pTrigger->tr_tm = tr_tm==TK_BEFORE ? TRIGGER_BEFORE : TRIGGER_AFTER;
  pTrigger->pWhen = sqlite3ExprDup(db, pWhen);
  pTrigger->pColumns = sqlite3IdListDup(db, pColumns);
  sqlite3TokenCopy(db, &pTrigger->nameToken,pName);
  assert( pParse->pNewTrigger==0 );
  pParse->pNewTrigger = pTrigger;

trigger_cleanup:
  sqlite3_free(zName);
  sqlite3SrcListDelete(pTableName);
  sqlite3IdListDelete(pColumns);
  sqlite3ExprDelete(pWhen);
  if( !pParse->pNewTrigger ){
    sqlite3DeleteTrigger(pTrigger);
  }else{
    assert( pParse->pNewTrigger==pTrigger );
................................................................................
  if( db->init.busy ){
    int n;
    Table *pTab;
    Trigger *pDel;
    pDel = sqlite3HashInsert(&db->aDb[iDb].pSchema->trigHash, 
                     pTrig->name, strlen(pTrig->name), pTrig);
    if( pDel ){
      assert( db->mallocFailed && pDel==pTrig );
      goto triggerfinish_cleanup;
    }
    n = strlen(pTrig->table) + 1;
    pTab = sqlite3HashFind(&pTrig->pTabSchema->tblHash, pTrig->table, n);
    assert( pTab!=0 );
    pTrig->pNext = pTab->pTrigger;
    pTab->pTrigger = pTrig;
................................................................................
  assert( !pParse->pNewTrigger );
  sqlite3DeleteTriggerStep(pStepList);
}

/*
** Make a copy of all components of the given trigger step.  This has
** the effect of copying all Expr.token.z values into memory obtained
** from sqlite3_malloc().  As initially created, the Expr.token.z values
** all point to the input string that was fed to the parser.  But that
** string is ephemeral - it will go away as soon as the sqlite3_exec()
** call that started the parser exits.  This routine makes a persistent
** copy of all the Expr.token.z strings so that the TriggerStep structure
** will be valid even after the sqlite3_exec() call returns.
*/
static void sqlitePersistTriggerStep(sqlite3 *db, TriggerStep *p){
  if( p->target.z ){
    p->target.z = (u8*)sqlite3DbStrNDup(db, (char*)p->target.z, p->target.n);
    p->target.dyn = 1;
  }
  if( p->pSelect ){
    Select *pNew = sqlite3SelectDup(db, p->pSelect);
    sqlite3SelectDelete(p->pSelect);
    p->pSelect = pNew;
  }
  if( p->pWhere ){
    Expr *pNew = sqlite3ExprDup(db, p->pWhere);
    sqlite3ExprDelete(p->pWhere);
    p->pWhere = pNew;
  }
  if( p->pExprList ){
    ExprList *pNew = sqlite3ExprListDup(db, p->pExprList);
    sqlite3ExprListDelete(p->pExprList);
    p->pExprList = pNew;
  }
  if( p->pIdList ){
    IdList *pNew = sqlite3IdListDup(db, p->pIdList);
    sqlite3IdListDelete(p->pIdList);
    p->pIdList = pNew;
  }
}

/*
** Turn a SELECT statement (that the pSelect parameter points to) into
** a trigger step.  Return a pointer to a TriggerStep structure.
**
** The parser calls this routine when it finds a SELECT statement in
** body of a TRIGGER.  
*/
TriggerStep *sqlite3TriggerSelectStep(sqlite3 *db, Select *pSelect){
  TriggerStep *pTriggerStep = sqlite3DbMallocZero(db, sizeof(TriggerStep));
  if( pTriggerStep==0 ) {
    sqlite3SelectDelete(pSelect);
    return 0;
  }

  pTriggerStep->op = TK_SELECT;
  pTriggerStep->pSelect = pSelect;
  pTriggerStep->orconf = OE_Default;
  sqlitePersistTriggerStep(db, pTriggerStep);

  return pTriggerStep;
}

/*
** Build a trigger step out of an INSERT statement.  Return a pointer
** to the new trigger step.
**
** The parser calls this routine when it sees an INSERT inside the
** body of a trigger.
*/
TriggerStep *sqlite3TriggerInsertStep(
  sqlite3 *db,        /* The database connection */
  Token *pTableName,  /* Name of the table into which we insert */
  IdList *pColumn,    /* List of columns in pTableName to insert into */
  ExprList *pEList,   /* The VALUE clause: a list of values to be inserted */
  Select *pSelect,    /* A SELECT statement that supplies values */
  int orconf          /* The conflict algorithm (OE_Abort, OE_Replace, etc.) */
){
  TriggerStep *pTriggerStep = sqlite3DbMallocZero(db, sizeof(TriggerStep));

  assert(pEList == 0 || pSelect == 0);
  assert(pEList != 0 || pSelect != 0);

  if( pTriggerStep ){
    pTriggerStep->op = TK_INSERT;
    pTriggerStep->pSelect = pSelect;
    pTriggerStep->target  = *pTableName;
    pTriggerStep->pIdList = pColumn;
    pTriggerStep->pExprList = pEList;
    pTriggerStep->orconf = orconf;
    sqlitePersistTriggerStep(db, pTriggerStep);
  }else{
    sqlite3IdListDelete(pColumn);
    sqlite3ExprListDelete(pEList);
    sqlite3SelectDelete(pSelect);
  }

  return pTriggerStep;
}

/*
** Construct a trigger step that implements an UPDATE statement and return
** a pointer to that trigger step.  The parser calls this routine when it
** sees an UPDATE statement inside the body of a CREATE TRIGGER.
*/
TriggerStep *sqlite3TriggerUpdateStep(
  sqlite3 *db,         /* The database connection */
  Token *pTableName,   /* Name of the table to be updated */
  ExprList *pEList,    /* The SET clause: list of column and new values */
  Expr *pWhere,        /* The WHERE clause */
  int orconf           /* The conflict algorithm. (OE_Abort, OE_Ignore, etc) */
){
  TriggerStep *pTriggerStep = sqlite3DbMallocZero(db, sizeof(TriggerStep));
  if( pTriggerStep==0 ){
     sqlite3ExprListDelete(pEList);
     sqlite3ExprDelete(pWhere);
     return 0;
  }

  pTriggerStep->op = TK_UPDATE;
  pTriggerStep->target  = *pTableName;
  pTriggerStep->pExprList = pEList;
  pTriggerStep->pWhere = pWhere;
  pTriggerStep->orconf = orconf;
  sqlitePersistTriggerStep(db, pTriggerStep);

  return pTriggerStep;
}

/*
** Construct a trigger step that implements a DELETE statement and return
** a pointer to that trigger step.  The parser calls this routine when it
** sees a DELETE statement inside the body of a CREATE TRIGGER.
*/
TriggerStep *sqlite3TriggerDeleteStep(
  sqlite3 *db,            /* Database connection */
  Token *pTableName,      /* The table from which rows are deleted */
  Expr *pWhere            /* The WHERE clause */
){
  TriggerStep *pTriggerStep = sqlite3DbMallocZero(db, sizeof(TriggerStep));
  if( pTriggerStep==0 ){
    sqlite3ExprDelete(pWhere);
    return 0;
  }

  pTriggerStep->op = TK_DELETE;
  pTriggerStep->target  = *pTableName;
  pTriggerStep->pWhere = pWhere;
  pTriggerStep->orconf = OE_Default;
  sqlitePersistTriggerStep(db, pTriggerStep);

  return pTriggerStep;
}

/* 
** Recursively delete a Trigger structure
*/
void sqlite3DeleteTrigger(Trigger *pTrigger){
  if( pTrigger==0 ) return;
  sqlite3DeleteTriggerStep(pTrigger->step_list);
  sqlite3_free(pTrigger->name);
  sqlite3_free(pTrigger->table);
  sqlite3ExprDelete(pTrigger->pWhen);
  sqlite3IdListDelete(pTrigger->pColumns);
  if( pTrigger->nameToken.dyn ) sqlite3_free((char*)pTrigger->nameToken.z);
  sqlite3_free(pTrigger);
}

/*
** This function is called to drop a trigger from the database schema. 
**
** This may be called directly from the parser and therefore identifies
** the trigger by name.  The sqlite3DropTriggerPtr() routine does the
................................................................................
  Trigger *pTrigger = 0;
  int i;
  const char *zDb;
  const char *zName;
  int nName;
  sqlite3 *db = pParse->db;

  if( db->mallocFailed ) goto drop_trigger_cleanup;
  if( SQLITE_OK!=sqlite3ReadSchema(pParse) ){
    goto drop_trigger_cleanup;
  }

  assert( pName->nSrc==1 );
  zDb = pName->a[0].zDatabase;
  zName = pName->a[0].zName;
................................................................................
  SrcList *pSrc;       /* SrcList to be returned */

  iDb = sqlite3SchemaToIndex(pParse->db, pStep->pTrig->pSchema);
  if( iDb==0 || iDb>=2 ){
    assert( iDb<pParse->db->nDb );
    sDb.z = (u8*)pParse->db->aDb[iDb].zName;
    sDb.n = strlen((char*)sDb.z);
    pSrc = sqlite3SrcListAppend(pParse->db, 0, &sDb, &pStep->target);
  } else {
    pSrc = sqlite3SrcListAppend(pParse->db, 0, &pStep->target, 0);
  }
  return pSrc;
}

/*
** Generate VDBE code for zero or more statements inside the body of a
** trigger.  
................................................................................
  Parse *pParse,            /* The parser context */
  TriggerStep *pStepList,   /* List of statements inside the trigger body */
  int orconfin              /* Conflict algorithm. (OE_Abort, etc) */  
){
  TriggerStep * pTriggerStep = pStepList;
  int orconf;
  Vdbe *v = pParse->pVdbe;
  sqlite3 *db = pParse->db;

  assert( pTriggerStep!=0 );
  assert( v!=0 );
  sqlite3VdbeAddOp(v, OP_ContextPush, 0, 0);
  VdbeComment((v, "# begin trigger %s", pStepList->pTrig->name));
  while( pTriggerStep ){
    orconf = (orconfin == OE_Default)?pTriggerStep->orconf:orconfin;
    pParse->trigStack->orconf = orconf;
    switch( pTriggerStep->op ){
      case TK_SELECT: {
        Select *ss = sqlite3SelectDup(db, pTriggerStep->pSelect);
        if( ss ){
          sqlite3SelectResolve(pParse, ss, 0);
          sqlite3Select(pParse, ss, SRT_Discard, 0, 0, 0, 0, 0);
          sqlite3SelectDelete(ss);
        }
        break;
      }
      case TK_UPDATE: {
        SrcList *pSrc;
        pSrc = targetSrcList(pParse, pTriggerStep);
        sqlite3VdbeAddOp(v, OP_ResetCount, 0, 0);
        sqlite3Update(pParse, pSrc,
                sqlite3ExprListDup(db, pTriggerStep->pExprList), 
                sqlite3ExprDup(db, pTriggerStep->pWhere), orconf);
        sqlite3VdbeAddOp(v, OP_ResetCount, 1, 0);
        break;
      }
      case TK_INSERT: {
        SrcList *pSrc;
        pSrc = targetSrcList(pParse, pTriggerStep);
        sqlite3VdbeAddOp(v, OP_ResetCount, 0, 0);
        sqlite3Insert(pParse, pSrc,
          sqlite3ExprListDup(db, pTriggerStep->pExprList), 
          sqlite3SelectDup(db, pTriggerStep->pSelect), 
          sqlite3IdListDup(db, pTriggerStep->pIdList), orconf);
        sqlite3VdbeAddOp(v, OP_ResetCount, 1, 0);
        break;
      }
      case TK_DELETE: {
        SrcList *pSrc;
        sqlite3VdbeAddOp(v, OP_ResetCount, 0, 0);
        pSrc = targetSrcList(pParse, pTriggerStep);
        sqlite3DeleteFrom(pParse, pSrc, 
                          sqlite3ExprDup(db, pTriggerStep->pWhere));
        sqlite3VdbeAddOp(v, OP_ResetCount, 1, 0);
        break;
      }
      default:
        assert(0);
    } 
    pTriggerStep = pTriggerStep->pNext;
................................................................................
      trigStackEntry.pNext = pParse->trigStack;
      trigStackEntry.ignoreJump = ignoreJump;
      pParse->trigStack = &trigStackEntry;
      sqlite3AuthContextPush(pParse, &sContext, p->name);

      /* code the WHEN clause */
      endTrigger = sqlite3VdbeMakeLabel(pParse->pVdbe);
      whenExpr = sqlite3ExprDup(pParse->db, p->pWhen);
      if( sqlite3ExprResolveNames(&sNC, whenExpr) ){
        pParse->trigStack = trigStackEntry.pNext;
        sqlite3ExprDelete(whenExpr);
        return 1;
      }
      sqlite3ExprIfFalse(pParse, whenExpr, endTrigger, 1);
      sqlite3ExprDelete(whenExpr);

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains C code routines that are called by the parser
** to handle UPDATE statements.
**
** $Id: update.c,v 1.138 2007/06/25 16:29:34 danielk1977 Exp $
*/
#include "sqliteInt.h"

#ifndef SQLITE_OMIT_VIRTUALTABLE
/* Forward declaration */
static void updateVirtualTable(
  Parse *pParse,       /* The parsing context */
................................................................................
  int triggers_exist = 0;      /* True if any row triggers exist */
#endif

  int newIdx      = -1;  /* index of trigger "new" temp table       */
  int oldIdx      = -1;  /* index of trigger "old" temp table       */

  sContext.pParse = 0;

  if( pParse->nErr || sqlite3MallocFailed() ){
    goto update_cleanup;
  }
  db = pParse->db;
  assert( pTabList->nSrc==1 );

  /* Locate the table which we want to update. 
  */
  pTab = sqlite3SrcListLookup(pParse, pTabList);
  if( pTab==0 ) goto update_cleanup;
  iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema);
................................................................................

  if( sqlite3IsReadOnly(pParse, pTab, triggers_exist) ){
    goto update_cleanup;
  }
  if( sqlite3ViewGetColumnNames(pParse, pTab) ){
    goto update_cleanup;
  }
  aXRef = sqliteMallocRaw( sizeof(int) * pTab->nCol );
  if( aXRef==0 ) goto update_cleanup;
  for(i=0; i<pTab->nCol; i++) aXRef[i] = -1;

  /* If there are FOR EACH ROW triggers, allocate cursors for the
  ** special OLD and NEW tables
  */
  if( triggers_exist ){
................................................................................
      for(i=0; i<pIdx->nColumn; i++){
        if( aXRef[pIdx->aiColumn[i]]>=0 ) break;
      }
    }
    if( i<pIdx->nColumn ) nIdx++;
  }
  if( nIdxTotal>0 ){
    apIdx = sqliteMallocRaw( sizeof(Index*) * nIdx + nIdxTotal );
    if( apIdx==0 ) goto update_cleanup;
    aIdxUsed = (char*)&apIdx[nIdx];
  }
  for(nIdx=j=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, j++){
    if( chngRowid ){
      i = 0;
    }else{
................................................................................
  }

  /* If we are trying to update a view, realize that view into
  ** a ephemeral table.
  */
  if( isView ){
    Select *pView;
    pView = sqlite3SelectDup(pTab->pSelect);
    sqlite3Select(pParse, pView, SRT_EphemTab, iCur, 0, 0, 0, 0);
    sqlite3SelectDelete(pView);
  }

  /* Begin the database scan
  */
  pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, 0);
................................................................................
    sqlite3VdbeAddOp(v, OP_Callback, 1, 0);
    sqlite3VdbeSetNumCols(v, 1);
    sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "rows updated", P3_STATIC);
  }

update_cleanup:
  sqlite3AuthContextPop(&sContext);
  sqliteFree(apIdx);
  sqliteFree(aXRef);
  sqlite3SrcListDelete(pTabList);
  sqlite3ExprListDelete(pChanges);
  sqlite3ExprDelete(pWhere);
  return;
}

#ifndef SQLITE_OMIT_VIRTUALTABLE
................................................................................
  Vdbe *v = pParse->pVdbe;  /* Virtual machine under construction */
  ExprList *pEList = 0;     /* The result set of the SELECT statement */
  Select *pSelect = 0;      /* The SELECT statement */
  Expr *pExpr;              /* Temporary expression */
  int ephemTab;             /* Table holding the result of the SELECT */
  int i;                    /* Loop counter */
  int addr;                 /* Address of top of loop */


  /* Construct the SELECT statement that will find the new values for
  ** all updated rows. 
  */
  pEList = sqlite3ExprListAppend(0, sqlite3CreateIdExpr("_rowid_"), 0);

  if( pRowid ){
    pEList = sqlite3ExprListAppend(pEList, sqlite3ExprDup(pRowid), 0);

  }
  assert( pTab->iPKey<0 );
  for(i=0; i<pTab->nCol; i++){
    if( aXRef[i]>=0 ){
      pExpr = sqlite3ExprDup(pChanges->a[aXRef[i]].pExpr);
    }else{
      pExpr = sqlite3CreateIdExpr(pTab->aCol[i].zName);
    }
    pEList = sqlite3ExprListAppend(pEList, pExpr, 0);
  }
  pSelect = sqlite3SelectNew(pEList, pSrc, pWhere, 0, 0, 0, 0, 0, 0);
  
  /* Create the ephemeral table into which the update results will
  ** be stored.
  */
  assert( v );
  ephemTab = pParse->nTab++;
  sqlite3VdbeAddOp(v, OP_OpenEphemeral, ephemTab, pTab->nCol+1+(pRowid!=0));

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains C code routines that are called by the parser
** to handle UPDATE statements.
**
** $Id: update.c,v 1.139 2007/08/16 04:30:40 drh Exp $
*/
#include "sqliteInt.h"

#ifndef SQLITE_OMIT_VIRTUALTABLE
/* Forward declaration */
static void updateVirtualTable(
  Parse *pParse,       /* The parsing context */
................................................................................
  int triggers_exist = 0;      /* True if any row triggers exist */
#endif

  int newIdx      = -1;  /* index of trigger "new" temp table       */
  int oldIdx      = -1;  /* index of trigger "old" temp table       */

  sContext.pParse = 0;
  db = pParse->db;
  if( pParse->nErr || db->mallocFailed ){
    goto update_cleanup;
  }

  assert( pTabList->nSrc==1 );

  /* Locate the table which we want to update. 
  */
  pTab = sqlite3SrcListLookup(pParse, pTabList);
  if( pTab==0 ) goto update_cleanup;
  iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema);
................................................................................

  if( sqlite3IsReadOnly(pParse, pTab, triggers_exist) ){
    goto update_cleanup;
  }
  if( sqlite3ViewGetColumnNames(pParse, pTab) ){
    goto update_cleanup;
  }
  aXRef = sqlite3DbMallocRaw(db, sizeof(int) * pTab->nCol );
  if( aXRef==0 ) goto update_cleanup;
  for(i=0; i<pTab->nCol; i++) aXRef[i] = -1;

  /* If there are FOR EACH ROW triggers, allocate cursors for the
  ** special OLD and NEW tables
  */
  if( triggers_exist ){
................................................................................
      for(i=0; i<pIdx->nColumn; i++){
        if( aXRef[pIdx->aiColumn[i]]>=0 ) break;
      }
    }
    if( i<pIdx->nColumn ) nIdx++;
  }
  if( nIdxTotal>0 ){
    apIdx = sqlite3DbMallocRaw(db, sizeof(Index*) * nIdx + nIdxTotal );
    if( apIdx==0 ) goto update_cleanup;
    aIdxUsed = (char*)&apIdx[nIdx];
  }
  for(nIdx=j=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, j++){
    if( chngRowid ){
      i = 0;
    }else{
................................................................................
  }

  /* If we are trying to update a view, realize that view into
  ** a ephemeral table.
  */
  if( isView ){
    Select *pView;
    pView = sqlite3SelectDup(db, pTab->pSelect);
    sqlite3Select(pParse, pView, SRT_EphemTab, iCur, 0, 0, 0, 0);
    sqlite3SelectDelete(pView);
  }

  /* Begin the database scan
  */
  pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, 0);
................................................................................
    sqlite3VdbeAddOp(v, OP_Callback, 1, 0);
    sqlite3VdbeSetNumCols(v, 1);
    sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "rows updated", P3_STATIC);
  }

update_cleanup:
  sqlite3AuthContextPop(&sContext);
  sqlite3_free(apIdx);
  sqlite3_free(aXRef);
  sqlite3SrcListDelete(pTabList);
  sqlite3ExprListDelete(pChanges);
  sqlite3ExprDelete(pWhere);
  return;
}

#ifndef SQLITE_OMIT_VIRTUALTABLE
................................................................................
  Vdbe *v = pParse->pVdbe;  /* Virtual machine under construction */
  ExprList *pEList = 0;     /* The result set of the SELECT statement */
  Select *pSelect = 0;      /* The SELECT statement */
  Expr *pExpr;              /* Temporary expression */
  int ephemTab;             /* Table holding the result of the SELECT */
  int i;                    /* Loop counter */
  int addr;                 /* Address of top of loop */
  sqlite3 *db = pParse->db; /* Database connection */

  /* Construct the SELECT statement that will find the new values for
  ** all updated rows. 
  */
  pEList = sqlite3ExprListAppend(pParse, 0, 
                                 sqlite3CreateIdExpr(pParse, "_rowid_"), 0);
  if( pRowid ){
    pEList = sqlite3ExprListAppend(pParse, pEList,
                                   sqlite3ExprDup(db, pRowid), 0);
  }
  assert( pTab->iPKey<0 );
  for(i=0; i<pTab->nCol; i++){
    if( aXRef[i]>=0 ){
      pExpr = sqlite3ExprDup(db, pChanges->a[aXRef[i]].pExpr);
    }else{
      pExpr = sqlite3CreateIdExpr(pParse, pTab->aCol[i].zName);
    }
    pEList = sqlite3ExprListAppend(pParse, pEList, pExpr, 0);
  }
  pSelect = sqlite3SelectNew(pParse, pEList, pSrc, pWhere, 0, 0, 0, 0, 0, 0);
  
  /* Create the ephemeral table into which the update results will
  ** be stored.
  */
  assert( v );
  ephemTab = pParse->nTab++;
  sqlite3VdbeAddOp(v, OP_OpenEphemeral, ephemTab, pTab->nCol+1+(pRowid!=0));

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains routines used to translate between UTF-8, 
** UTF-16, UTF-16BE, and UTF-16LE.
**
** $Id: utf.c,v 1.53 2007/08/07 17:04:59 drh Exp $
**
** Notes on UTF-8:
**
**   Byte-0    Byte-1    Byte-2    Byte-3    Value
**  0xxxxxxx                                 00000000 00000000 0xxxxxxx
**  110yyyyy  10xxxxxx                       00000000 00000yyy yyxxxxxx
**  1110zzzz  10yyyyyy  10xxxxxx             00000000 zzzzyyyy yyxxxxxx
................................................................................

#ifndef SQLITE_OMIT_UTF16
/*
** This routine transforms the internal text encoding used by pMem to
** desiredEnc. It is an error if the string is already of the desired
** encoding, or if *pMem does not contain a string value.
*/
int sqlite3VdbeMemTranslate(Mem *pMem, u8 desiredEnc){
  unsigned char zShort[NBFS]; /* Temporary short output buffer */
  int len;                    /* Maximum length of output string in bytes */
  unsigned char *zOut;                  /* Output buffer */
  unsigned char *zIn;                   /* Input iterator */
  unsigned char *zTerm;                 /* End of input */
  unsigned char *z;                     /* Output iterator */
  unsigned int c;
................................................................................
    len = pMem->n * 2 + 2;
  }

  /* Set zIn to point at the start of the input buffer and zTerm to point 1
  ** byte past the end.
  **
  ** Variable zOut is set to point at the output buffer. This may be space
  ** obtained from malloc(), or Mem.zShort, if it large enough and not in
  ** use, or the zShort array on the stack (see above).
  */
  zIn = (u8*)pMem->z;
  zTerm = &zIn[pMem->n];
  if( len>NBFS ){
    zOut = sqliteMallocRaw(len);
    if( !zOut ) return SQLITE_NOMEM;
  }else{
    zOut = zShort;
  }
  z = zOut;

  if( pMem->enc==SQLITE_UTF8 ){
................................................................................
  }
  return r;
}

#ifndef SQLITE_OMIT_UTF16
/*
** Convert a UTF-16 string in the native encoding into a UTF-8 string.
** Memory to hold the UTF-8 string is obtained from malloc and must be
** freed by the calling function.
**
** NULL is returned if there is an allocation error.
*/
char *sqlite3Utf16to8(const void *z, int nByte){
  Mem m;
  memset(&m, 0, sizeof(m));
  sqlite3VdbeMemSetStr(&m, z, nByte, SQLITE_UTF16NATIVE, SQLITE_STATIC);
  sqlite3VdbeChangeEncoding(&m, SQLITE_UTF8);
  assert( (m.flags & MEM_Term)!=0 || sqlite3MallocFailed() );
  assert( (m.flags & MEM_Str)!=0 || sqlite3MallocFailed() );
  return (m.flags & MEM_Dyn)!=0 ? m.z : sqliteStrDup(m.z);
}

/*
** pZ is a UTF-16 encoded unicode string. If nChar is less than zero,
** return the number of bytes up to (but not including), the first pair
** of consecutive 0x00 bytes in pZ. If nChar is not less than zero,
** then return the number of bytes in the first nChar unicode characters

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains routines used to translate between UTF-8, 
** UTF-16, UTF-16BE, and UTF-16LE.
**
** $Id: utf.c,v 1.54 2007/08/16 04:30:40 drh Exp $
**
** Notes on UTF-8:
**
**   Byte-0    Byte-1    Byte-2    Byte-3    Value
**  0xxxxxxx                                 00000000 00000000 0xxxxxxx
**  110yyyyy  10xxxxxx                       00000000 00000yyy yyxxxxxx
**  1110zzzz  10yyyyyy  10xxxxxx             00000000 zzzzyyyy yyxxxxxx
................................................................................

#ifndef SQLITE_OMIT_UTF16
/*
** This routine transforms the internal text encoding used by pMem to
** desiredEnc. It is an error if the string is already of the desired
** encoding, or if *pMem does not contain a string value.
*/
int sqlite3VdbeMemTranslate(sqlite3 *db, Mem *pMem, u8 desiredEnc){
  unsigned char zShort[NBFS]; /* Temporary short output buffer */
  int len;                    /* Maximum length of output string in bytes */
  unsigned char *zOut;                  /* Output buffer */
  unsigned char *zIn;                   /* Input iterator */
  unsigned char *zTerm;                 /* End of input */
  unsigned char *z;                     /* Output iterator */
  unsigned int c;
................................................................................
    len = pMem->n * 2 + 2;
  }

  /* Set zIn to point at the start of the input buffer and zTerm to point 1
  ** byte past the end.
  **
  ** Variable zOut is set to point at the output buffer. This may be space
  ** obtained from sqlite3_malloc(), or Mem.zShort, if it large enough and
  ** not in use, or the zShort array on the stack (see above).
  */
  zIn = (u8*)pMem->z;
  zTerm = &zIn[pMem->n];
  if( len>NBFS ){
    zOut = sqlite3DbMallocRaw(db, len);
    if( !zOut ) return SQLITE_NOMEM;
  }else{
    zOut = zShort;
  }
  z = zOut;

  if( pMem->enc==SQLITE_UTF8 ){
................................................................................
  }
  return r;
}

#ifndef SQLITE_OMIT_UTF16
/*
** Convert a UTF-16 string in the native encoding into a UTF-8 string.
** Memory to hold the UTF-8 string is obtained from sqlite3_malloc and must
** be freed by the calling function.
**
** NULL is returned if there is an allocation error.
*/
char *sqlite3Utf16to8(sqlite3 *db, const void *z, int nByte){
  Mem m;
  memset(&m, 0, sizeof(m));
  sqlite3VdbeMemSetStr(db, &m, z, nByte, SQLITE_UTF16NATIVE, SQLITE_STATIC);
  sqlite3VdbeChangeEncoding(db, &m, SQLITE_UTF8);
  assert( (m.flags & MEM_Term)!=0 || db->mallocFailed );
  assert( (m.flags & MEM_Str)!=0 || db->mallocFailed );
  return (m.flags & MEM_Dyn)!=0 ? m.z : sqlite3DbStrDup(db, m.z);
}

/*
** pZ is a UTF-16 encoded unicode string. If nChar is less than zero,
** return the number of bytes up to (but not including), the first pair
** of consecutive 0x00 bytes in pZ. If nChar is not less than zero,
** then return the number of bytes in the first nChar unicode characters

**
*************************************************************************
** Utility functions used throughout sqlite.
**
** This file contains functions for allocating memory, comparing
** strings, and stuff like that.
**
** $Id: util.c,v 1.207 2007/06/26 00:37:28 drh Exp $
*/
#include "sqliteInt.h"
#include "os.h"
#include <stdarg.h>
#include <ctype.h>


................................................................................
#if !defined(SQLITE_OMIT_BLOB_LITERAL) || defined(SQLITE_HAS_CODEC)
/*
** Convert a BLOB literal of the form "x'hhhhhh'" into its binary
** value.  Return a pointer to its binary value.  Space to hold the
** binary value has been obtained from malloc and must be freed by
** the calling routine.
*/
void *sqlite3HexToBlob(const char *z){
  char *zBlob;
  int i;
  int n = strlen(z);
  if( n%2 ) return 0;

  zBlob = (char *)sqliteMalloc(n/2);
  if( zBlob ){
    for(i=0; i<n; i+=2){
      zBlob[i/2] = (hexToInt(z[i])<<4) | hexToInt(z[i+1]);
    }
  }
  return zBlob;
}
................................................................................
    return 0;
  }else {
    db->magic = SQLITE_MAGIC_ERROR;
    db->u1.isInterrupted = 1;
    return 1;
  }
}

/*
** Return a pointer to the ThreadData associated with the calling thread.
*/
ThreadData *sqlite3ThreadData(){
  ThreadData *p = (ThreadData*)sqlite3OsThreadSpecificData(1);
  if( !p ){
    sqlite3FailedMalloc();
  }
  return p;
}

/*
** Return a pointer to the ThreadData associated with the calling thread.
** If no ThreadData has been allocated to this thread yet, return a pointer
** to a substitute ThreadData structure that is all zeros. 
*/
const ThreadData *sqlite3ThreadDataReadOnly(){
  static const ThreadData zeroData = {0};  /* Initializer to silence warnings
                                           ** from broken compilers */
  const ThreadData *pTd = sqlite3OsThreadSpecificData(0);
  return pTd ? pTd : &zeroData;
}

/*
** Check to see if the ThreadData for this thread is all zero.  If it
** is, then deallocate it. 
*/
void sqlite3ReleaseThreadData(){
  sqlite3OsThreadSpecificData(-1);
}

**
*************************************************************************
** Utility functions used throughout sqlite.
**
** This file contains functions for allocating memory, comparing
** strings, and stuff like that.
**
** $Id: util.c,v 1.208 2007/08/16 04:30:40 drh Exp $
*/
#include "sqliteInt.h"
#include "os.h"
#include <stdarg.h>
#include <ctype.h>


................................................................................
#if !defined(SQLITE_OMIT_BLOB_LITERAL) || defined(SQLITE_HAS_CODEC)
/*
** Convert a BLOB literal of the form "x'hhhhhh'" into its binary
** value.  Return a pointer to its binary value.  Space to hold the
** binary value has been obtained from malloc and must be freed by
** the calling routine.
*/
void *sqlite3HexToBlob(sqlite3 *db, const char *z){
  char *zBlob;
  int i;
  int n = strlen(z);
  if( n%2 ) return 0;

  zBlob = (char *)sqlite3DbMallocRaw(db, n/2);
  if( zBlob ){
    for(i=0; i<n; i+=2){
      zBlob[i/2] = (hexToInt(z[i])<<4) | hexToInt(z[i+1]);
    }
  }
  return zBlob;
}
................................................................................
    return 0;
  }else {
    db->magic = SQLITE_MAGIC_ERROR;
    db->u1.isInterrupted = 1;
    return 1;
  }
}

**
*************************************************************************
** This file contains code used to implement the VACUUM command.
**
** Most of the code in this file may be omitted by defining the
** SQLITE_OMIT_VACUUM macro.
**
** $Id: vacuum.c,v 1.69 2007/03/27 16:19:52 danielk1977 Exp $
*/
#include "sqliteInt.h"
#include "vdbeInt.h"
#include "os.h"

#if !defined(SQLITE_OMIT_VACUUM) && !defined(SQLITE_OMIT_ATTACH)
/*
................................................................................
  rc = execSql(db, zSql);
  if( rc!=SQLITE_OK ) goto end_of_vacuum;
  pDb = &db->aDb[db->nDb-1];
  assert( strcmp(db->aDb[db->nDb-1].zName,"vacuum_db")==0 );
  pTemp = db->aDb[db->nDb-1].pBt;
  sqlite3BtreeSetPageSize(pTemp, sqlite3BtreeGetPageSize(pMain),
     sqlite3BtreeGetReserve(pMain));
  if( sqlite3MallocFailed() ){
    rc = SQLITE_NOMEM;
    goto end_of_vacuum;
  }
  assert( sqlite3BtreeGetPageSize(pTemp)==sqlite3BtreeGetPageSize(pMain) );
  rc = execSql(db, "PRAGMA vacuum_db.synchronous=OFF");
  if( rc!=SQLITE_OK ){
    goto end_of_vacuum;

**
*************************************************************************
** This file contains code used to implement the VACUUM command.
**
** Most of the code in this file may be omitted by defining the
** SQLITE_OMIT_VACUUM macro.
**
** $Id: vacuum.c,v 1.70 2007/08/16 04:30:40 drh Exp $
*/
#include "sqliteInt.h"
#include "vdbeInt.h"
#include "os.h"

#if !defined(SQLITE_OMIT_VACUUM) && !defined(SQLITE_OMIT_ATTACH)
/*
................................................................................
  rc = execSql(db, zSql);
  if( rc!=SQLITE_OK ) goto end_of_vacuum;
  pDb = &db->aDb[db->nDb-1];
  assert( strcmp(db->aDb[db->nDb-1].zName,"vacuum_db")==0 );
  pTemp = db->aDb[db->nDb-1].pBt;
  sqlite3BtreeSetPageSize(pTemp, sqlite3BtreeGetPageSize(pMain),
     sqlite3BtreeGetReserve(pMain));
  if( db->mallocFailed ){
    rc = SQLITE_NOMEM;
    goto end_of_vacuum;
  }
  assert( sqlite3BtreeGetPageSize(pTemp)==sqlite3BtreeGetPageSize(pMain) );
  rc = execSql(db, "PRAGMA vacuum_db.synchronous=OFF");
  if( rc!=SQLITE_OK ){
    goto end_of_vacuum;

**
** Various scripts scan this source file in order to generate HTML
** documentation, headers files, or other derived files.  The formatting
** of the code in this file is, therefore, important.  See other comments
** in this file for details.  If in doubt, do not deviate from existing
** commenting and indentation practices when changing or adding code.
**
** $Id: vdbe.c,v 1.639 2007/07/26 06:50:06 danielk1977 Exp $
*/
#include "sqliteInt.h"
#include "os.h"
#include <ctype.h>
#include <math.h>
#include "vdbeInt.h"

................................................................................
** Convert the given stack entity into a string if it isn't one
** already. Return non-zero if a malloc() fails.
*/
#define Stringify(P, enc) \
   if(((P)->flags&(MEM_Str|MEM_Blob))==0 && sqlite3VdbeMemStringify(P,enc)) \
     { goto no_mem; }

/*
** Convert the given stack entity into a string that has been obtained
** from sqliteMalloc().  This is different from Stringify() above in that
** Stringify() will use the NBFS bytes of static string space if the string
** will fit but this routine always mallocs for space.
** Return non-zero if we run out of memory.
*/
#define Dynamicify(P,enc) sqlite3VdbeMemDynamicify(P)

/*
** The header of a record consists of a sequence variable-length integers.
** These integers are almost always small and are encoded as a single byte.
** The following macro takes advantage this fact to provide a fast decode
** of the integers in a record header.  It is faster for the common case
** where the integer is a single byte.  It is a little slower when the
** integer is two or more bytes.  But overall it is faster.
................................................................................
*/
static Cursor *allocateCursor(Vdbe *p, int iCur, int iDb){
  Cursor *pCx;
  assert( iCur<p->nCursor );
  if( p->apCsr[iCur] ){
    sqlite3VdbeFreeCursor(p, p->apCsr[iCur]);
  }
  p->apCsr[iCur] = pCx = sqliteMalloc( sizeof(Cursor) );
  if( pCx ){
    pCx->iDb = iDb;
  }
  return pCx;
}

/*
** Try to convert a value into a numeric representation if we can
** do so without loss of information.  In other words, if the string
** looks like a number, convert it into a number.  If it does not
** look like a number, leave it alone.
*/
static void applyNumericAffinity(Mem *pRec){
  if( (pRec->flags & (MEM_Real|MEM_Int))==0 ){
    int realnum;
    sqlite3VdbeMemNulTerminate(pRec);
    if( (pRec->flags&MEM_Str)
         && sqlite3IsNumber(pRec->z, &realnum, pRec->enc) ){
      i64 value;
      sqlite3VdbeChangeEncoding(pRec, SQLITE_UTF8);
      if( !realnum && sqlite3Atoi64(pRec->z, &value) ){
        sqlite3VdbeMemRelease(pRec);
        pRec->u.i = value;
        pRec->flags = MEM_Int;
      }else{
        sqlite3VdbeMemRealify(pRec);
      }
................................................................................
**
** SQLITE_AFF_TEXT:
**    Convert pRec to a text representation.
**
** SQLITE_AFF_NONE:
**    No-op.  pRec is unchanged.
*/
static void applyAffinity(Mem *pRec, char affinity, u8 enc){





  if( affinity==SQLITE_AFF_TEXT ){
    /* Only attempt the conversion to TEXT if there is an integer or real
    ** representation (blob and NULL do not get converted) but no string
    ** representation.
    */
    if( 0==(pRec->flags&MEM_Str) && (pRec->flags&(MEM_Real|MEM_Int)) ){
      sqlite3VdbeMemStringify(pRec, enc);
    }
    pRec->flags &= ~(MEM_Real|MEM_Int);
  }else if( affinity!=SQLITE_AFF_NONE ){
    assert( affinity==SQLITE_AFF_INTEGER || affinity==SQLITE_AFF_REAL
             || affinity==SQLITE_AFF_NUMERIC );
    applyNumericAffinity(pRec);
    if( pRec->flags & MEM_Real ){
      sqlite3VdbeIntegerAffinity(pRec);
    }
  }
}

/*
................................................................................
** SQLITE_ROW.
**
** If an attempt is made to open a locked database, then this routine
** will either invoke the busy callback (if there is one) or it will
** return SQLITE_BUSY.
**
** If an error occurs, an error message is written to memory obtained
** from sqliteMalloc() and p->zErrMsg is made to point to that memory.
** The error code is stored in p->rc and this routine returns SQLITE_ERROR.
**
** If the callback ever returns non-zero, then the program exits
** immediately.  There will be no error message but the p->rc field is
** set to SQLITE_ABORT and this routine will return SQLITE_ERROR.
**
** A memory allocation error causes p->rc to be set to SQLITE_NOMEM and this
................................................................................
  if( sqlite3OsFileExists("vdbe_trace") ){
    p->trace = stdout;
  }
#endif
  for(pc=p->pc; rc==SQLITE_OK; pc++){
    assert( pc>=0 && pc<p->nOp );
    assert( pTos<=&p->aStack[pc] );
    if( sqlite3MallocFailed() ) goto no_mem;
#ifdef VDBE_PROFILE
    origPc = pc;
    start = hwtime();
#endif
    pOp = &p->aOp[pc];

    /* Only allow tracing if SQLITE_DEBUG is defined.
................................................................................
  assert( pOp->p1 < SQLITE_MAX_LENGTH );

#ifndef SQLITE_OMIT_UTF16
  if( encoding!=SQLITE_UTF8 ){
    pTos++;
    sqlite3VdbeMemSetStr(pTos, pOp->p3, -1, SQLITE_UTF8, SQLITE_STATIC);
    if( SQLITE_OK!=sqlite3VdbeChangeEncoding(pTos, encoding) ) goto no_mem;
    if( SQLITE_OK!=sqlite3VdbeMemDynamicify(pTos) ) goto no_mem;
    pTos->flags &= ~(MEM_Dyn);
    pTos->flags |= MEM_Static;
    if( pOp->p3type==P3_DYNAMIC ){
      sqliteFree(pOp->p3);
    }
    pOp->p3type = P3_DYNAMIC;
    pOp->p3 = pTos->z;
    pOp->p1 = pTos->n;
    assert( pOp->p1 < SQLITE_MAX_LENGTH ); /* Due to SQLITE_MAX_SQL_LENGTH */
    break;
  }
................................................................................
  pOp->p1 = strlen(pOp->p3)/2;
  assert( SQLITE_MAX_SQL_LENGTH < SQLITE_MAX_LENGTH );
  assert( pOp->p1 < SQLITE_MAX_LENGTH );
  if( pOp->p1 ){
    char *zBlob = sqlite3HexToBlob(pOp->p3);
    if( !zBlob ) goto no_mem;
    if( pOp->p3type==P3_DYNAMIC ){
      sqliteFree(pOp->p3);
    }
    pOp->p3 = zBlob;
    pOp->p3type = P3_DYNAMIC;
  }else{
    if( pOp->p3type==P3_DYNAMIC ){
      sqliteFree(pOp->p3);
    }
    pOp->p3type = P3_STATIC;
    pOp->p3 = "";
  }

  /* Fall through to the next case, OP_Blob. */
}
................................................................................
**
** Look at the first P1+2 elements of the stack.  Append them all 
** together with the lowest element first.  The original P1+2 elements
** are popped from the stack if P2==0 and retained if P2==1.  If
** any element of the stack is NULL, then the result is NULL.
**
** When P1==1, this routine makes a copy of the top stack element
** into memory obtained from sqliteMalloc().
*/
case OP_Concat: {           /* same as TK_CONCAT */
  char *zNew;
  i64 nByte;
  int nField;
  int i, j;
  Mem *pTerm;
................................................................................
  }else{
    /* Otherwise malloc() space for the result and concatenate all the
    ** stack values.
    */
    if( nByte+2>SQLITE_MAX_LENGTH ){
      goto too_big;
    }
    zNew = sqliteMallocRaw( nByte+2 );
    if( zNew==0 ) goto no_mem;
    j = 0;
    pTerm = &pTos[1-nField];
    for(i=j=0; i<nField; i++, pTerm++){
      int n = pTerm->n;
      assert( pTerm->flags & (MEM_Str|MEM_Blob) );
      memcpy(&zNew[j], pTerm->z, n);
................................................................................
    assert( pOp[-1].p3type==P3_COLLSEQ );
    assert( pOp[-1].opcode==OP_CollSeq );
    ctx.pColl = (CollSeq *)pOp[-1].p3;
  }
  if( sqlite3SafetyOff(db) ) goto abort_due_to_misuse;
  (*ctx.pFunc->xFunc)(&ctx, n, apVal);
  if( sqlite3SafetyOn(db) ) goto abort_due_to_misuse;
  if( sqlite3MallocFailed() ){
    /* Even though a malloc() has failed, the implementation of the
    ** user function may have called an sqlite3_result_XXX() function
    ** to return a value. The following call releases any resources
    ** associated with such a value.
    **
    ** Note: Maybe MemRelease() should be called if sqlite3SafetyOn()
    ** fails also (the if(...) statement above). But if people are
................................................................................
    u8 *zEndHdr;     /* Pointer to first byte after the header */
    u32 offset;      /* Offset into the data */
    int szHdrSz;     /* Size of the header size field at start of record */
    int avail;       /* Number of bytes of available data */

    aType = pC->aType;
    if( aType==0 ){
      pC->aType = aType = sqliteMallocRaw( 2*nField*sizeof(aType) );
    }
    if( aType==0 ){
      goto no_mem;
    }
    pC->aOffset = aOffset = &aType[nField];
    pC->payloadSize = payloadSize;
    pC->cacheStatus = p->cacheCtr;
................................................................................
  nByte = nHdr+nData-nZero;
  if( nByte>SQLITE_MAX_LENGTH ){
    goto too_big;
  }

  /* Allocate space for the new record. */
  if( nByte>sizeof(zTemp) ){
    zNewRecord = sqliteMallocRaw(nByte);
    if( !zNewRecord ){
      goto no_mem;
    }
  }else{
    zNewRecord = (u8*)zTemp;
  }

................................................................................
    if( pTos->flags & MEM_Null ){
      pTos->z = 0;
      pTos->n = 0;
    }else{
      assert( pTos->flags & (MEM_Blob|MEM_Str) );
    }
    if( pC->pseudoTable ){
      sqliteFree(pC->pData);
      pC->iKey = iKey;
      pC->nData = pTos->n;
      if( pTos->flags & MEM_Dyn ){
        pC->pData = pTos->z;
        pTos->flags = MEM_Null;
      }else{
        pC->pData = sqliteMallocRaw( pC->nData+2 );
        if( !pC->pData ) goto no_mem;
        memcpy(pC->pData, pTos->z, pC->nData);
        pC->pData[pC->nData] = 0;
        pC->pData[pC->nData+1] = 0;
      }
      pC->nullRow = 0;
    }else{
................................................................................
      goto too_big;
    }
    pTos->n = n;
    if( n<=NBFS ){
      pTos->flags = MEM_Blob | MEM_Short;
      pTos->z = pTos->zShort;
    }else{
      char *z = sqliteMallocRaw( n );
      if( z==0 ) goto no_mem;
      pTos->flags = MEM_Blob | MEM_Dyn;
      pTos->xDel = 0;
      pTos->z = z;
    }
    if( pC->isIndex ){
      rc = sqlite3BtreeKey(pCrsr, 0, n, pTos->z);
................................................................................
  zSql = sqlite3MPrintf(
     "SELECT name, rootpage, sql FROM '%q'.%s WHERE %s",
     db->aDb[iDb].zName, zMaster, pOp->p3);
  if( zSql==0 ) goto no_mem;
  sqlite3SafetyOff(db);
  assert( db->init.busy==0 );
  db->init.busy = 1;
  assert( !sqlite3MallocFailed() );
  rc = sqlite3_exec(db, zSql, sqlite3InitCallback, &initData, 0);
  if( rc==SQLITE_ABORT ) rc = initData.rc;
  sqliteFree(zSql);
  db->init.busy = 0;
  sqlite3SafetyOn(db);
  if( rc==SQLITE_NOMEM ){
    sqlite3FailedMalloc();
    goto no_mem;
  }
  break;  
}

#if !defined(SQLITE_OMIT_ANALYZE) && !defined(SQLITE_OMIT_PARSER)
/* Opcode: LoadAnalysis P1 * *
................................................................................
  char *z;
  Mem *pnErr;

  for(nRoot=0; &pTos[-nRoot]>=p->aStack; nRoot++){
    if( (pTos[-nRoot].flags & MEM_Int)==0 ) break;
  }
  assert( nRoot>0 );
  aRoot = sqliteMallocRaw( sizeof(int)*(nRoot+1) );
  if( aRoot==0 ) goto no_mem;
  j = pOp->p1;
  assert( j>=0 && j<p->nMem );
  pnErr = &p->aMem[j];
  assert( (pnErr->flags & MEM_Int)!=0 );
  for(j=0; j<nRoot; j++){
    aRoot[j] = (pTos-j)->u.i;
................................................................................
    pTos->z = z;
    pTos->n = strlen(z);
    pTos->flags = MEM_Str | MEM_Dyn | MEM_Term;
    pTos->xDel = 0;
  }
  pTos->enc = SQLITE_UTF8;
  sqlite3VdbeChangeEncoding(pTos, encoding);
  sqliteFree(aRoot);
  break;
}
#endif /* SQLITE_OMIT_INTEGRITY_CHECK */

/* Opcode: FifoWrite * * *
**
** Write the integer on the top of the stack
** into the Fifo.
*/
case OP_FifoWrite: {        /* no-push */
  assert( pTos>=p->aStack );
  sqlite3VdbeMemIntegerify(pTos);
  sqlite3VdbeFifoPush(&p->sFifo, pTos->u.i);


  assert( (pTos->flags & MEM_Dyn)==0 );
  pTos--;
  break;
}

/* Opcode: FifoRead * P2 *
**
................................................................................
  int i = p->contextStackTop++;
  Context *pContext;

  assert( i>=0 );
  /* FIX ME: This should be allocated as part of the vdbe at compile-time */
  if( i>=p->contextStackDepth ){
    p->contextStackDepth = i+1;
    p->contextStack = sqliteReallocOrFree(p->contextStack,
                                          sizeof(Context)*(i+1));
    if( p->contextStack==0 ) goto no_mem;
  }
  pContext = &p->contextStack[i];
  pContext->lastRowid = db->lastRowid;
  pContext->nChange = p->nChange;
  pContext->sFifo = p->sFifo;
................................................................................
  ctx.pMem = pMem = &p->aMem[pOp->p1];
  pMem->n++;
  ctx.s.flags = MEM_Null;
  ctx.s.z = 0;
  ctx.s.xDel = 0;
  ctx.isError = 0;
  ctx.pColl = 0;

  if( ctx.pFunc->needCollSeq ){
    assert( pOp>p->aOp );
    assert( pOp[-1].p3type==P3_COLLSEQ );
    assert( pOp[-1].opcode==OP_CollSeq );
    ctx.pColl = (CollSeq *)pOp[-1].p3;
  }
  (ctx.pFunc->xStep)(&ctx, n, apVal);
................................................................................

    /* Initialise vdbe cursor object */
    pCur = allocateCursor(p, pOp->p1, -1);
    if( pCur ){
      pCur->pVtabCursor = pVtabCursor;
      pCur->pModule = pVtabCursor->pVtab->pModule;
    }else{

      pModule->xClose(pVtabCursor);
    }
  }
  break;
}
#endif /* SQLITE_OMIT_VIRTUALTABLE */

................................................................................
  sqlite3SetString(&p->zErrMsg, "string or blob too big", (char*)0);
  rc = SQLITE_TOOBIG;
  goto vdbe_halt;

  /* Jump to here if a malloc() fails.
  */
no_mem:

  sqlite3SetString(&p->zErrMsg, "out of memory", (char*)0);
  rc = SQLITE_NOMEM;
  goto vdbe_halt;

  /* Jump to here for an SQLITE_MISUSE error.
  */
abort_due_to_misuse:
................................................................................
  /* Fall thru into abort_due_to_error */

  /* Jump to here for any other kind of fatal error.  The "rc" variable
  ** should hold the error number.
  */
abort_due_to_error:
  if( p->zErrMsg==0 ){
    if( sqlite3MallocFailed() ) rc = SQLITE_NOMEM;
    sqlite3SetString(&p->zErrMsg, sqlite3ErrStr(rc), (char*)0);
  }
  goto vdbe_halt;

  /* Jump to here if the sqlite3_interrupt() API sets the interrupt
  ** flag.
  */

**
** Various scripts scan this source file in order to generate HTML
** documentation, headers files, or other derived files.  The formatting
** of the code in this file is, therefore, important.  See other comments
** in this file for details.  If in doubt, do not deviate from existing
** commenting and indentation practices when changing or adding code.
**
** $Id: vdbe.c,v 1.640 2007/08/16 04:30:40 drh Exp $
*/
#include "sqliteInt.h"
#include "os.h"
#include <ctype.h>
#include <math.h>
#include "vdbeInt.h"

................................................................................
** Convert the given stack entity into a string if it isn't one
** already. Return non-zero if a malloc() fails.
*/
#define Stringify(P, enc) \
   if(((P)->flags&(MEM_Str|MEM_Blob))==0 && sqlite3VdbeMemStringify(P,enc)) \
     { goto no_mem; }










/*
** The header of a record consists of a sequence variable-length integers.
** These integers are almost always small and are encoded as a single byte.
** The following macro takes advantage this fact to provide a fast decode
** of the integers in a record header.  It is faster for the common case
** where the integer is a single byte.  It is a little slower when the
** integer is two or more bytes.  But overall it is faster.
................................................................................
*/
static Cursor *allocateCursor(Vdbe *p, int iCur, int iDb){
  Cursor *pCx;
  assert( iCur<p->nCursor );
  if( p->apCsr[iCur] ){
    sqlite3VdbeFreeCursor(p, p->apCsr[iCur]);
  }
  p->apCsr[iCur] = pCx = sqlite3MallocZero( sizeof(Cursor) );
  if( pCx ){
    pCx->iDb = iDb;
  }
  return pCx;
}

/*
** Try to convert a value into a numeric representation if we can
** do so without loss of information.  In other words, if the string
** looks like a number, convert it into a number.  If it does not
** look like a number, leave it alone.
*/
static void applyNumericAffinity(sqlite3 *db, Mem *pRec){
  if( (pRec->flags & (MEM_Real|MEM_Int))==0 ){
    int realnum;
    sqlite3VdbeMemNulTerminate(db, pRec);
    if( (pRec->flags&MEM_Str)
         && sqlite3IsNumber(pRec->z, &realnum, pRec->enc) ){
      i64 value;
      sqlite3VdbeChangeEncoding(db, pRec, SQLITE_UTF8);
      if( !realnum && sqlite3Atoi64(pRec->z, &value) ){
        sqlite3VdbeMemRelease(pRec);
        pRec->u.i = value;
        pRec->flags = MEM_Int;
      }else{
        sqlite3VdbeMemRealify(pRec);
      }
................................................................................
**
** SQLITE_AFF_TEXT:
**    Convert pRec to a text representation.
**
** SQLITE_AFF_NONE:
**    No-op.  pRec is unchanged.
*/
static void applyAffinity(
  sqlite3 *db,        /* Report malloc() errors to this db connection */
  Mem *pRec,          /* The value to apply affinity to */
  char affinity,      /* The affinity to be applied */
  u8 enc              /* Use this text encoding */
){
  if( affinity==SQLITE_AFF_TEXT ){
    /* Only attempt the conversion to TEXT if there is an integer or real
    ** representation (blob and NULL do not get converted) but no string
    ** representation.
    */
    if( 0==(pRec->flags&MEM_Str) && (pRec->flags&(MEM_Real|MEM_Int)) ){
      sqlite3VdbeMemStringify(db, pRec, enc);
    }
    pRec->flags &= ~(MEM_Real|MEM_Int);
  }else if( affinity!=SQLITE_AFF_NONE ){
    assert( affinity==SQLITE_AFF_INTEGER || affinity==SQLITE_AFF_REAL
             || affinity==SQLITE_AFF_NUMERIC );
    applyNumericAffinity(db, pRec);
    if( pRec->flags & MEM_Real ){
      sqlite3VdbeIntegerAffinity(pRec);
    }
  }
}

/*
................................................................................
** SQLITE_ROW.
**
** If an attempt is made to open a locked database, then this routine
** will either invoke the busy callback (if there is one) or it will
** return SQLITE_BUSY.
**
** If an error occurs, an error message is written to memory obtained
** from sqlite3_malloc() and p->zErrMsg is made to point to that memory.
** The error code is stored in p->rc and this routine returns SQLITE_ERROR.
**
** If the callback ever returns non-zero, then the program exits
** immediately.  There will be no error message but the p->rc field is
** set to SQLITE_ABORT and this routine will return SQLITE_ERROR.
**
** A memory allocation error causes p->rc to be set to SQLITE_NOMEM and this
................................................................................
  if( sqlite3OsFileExists("vdbe_trace") ){
    p->trace = stdout;
  }
#endif
  for(pc=p->pc; rc==SQLITE_OK; pc++){
    assert( pc>=0 && pc<p->nOp );
    assert( pTos<=&p->aStack[pc] );
    if( db->mallocFailed ) goto no_mem;
#ifdef VDBE_PROFILE
    origPc = pc;
    start = hwtime();
#endif
    pOp = &p->aOp[pc];

    /* Only allow tracing if SQLITE_DEBUG is defined.
................................................................................
  assert( pOp->p1 < SQLITE_MAX_LENGTH );

#ifndef SQLITE_OMIT_UTF16
  if( encoding!=SQLITE_UTF8 ){
    pTos++;
    sqlite3VdbeMemSetStr(pTos, pOp->p3, -1, SQLITE_UTF8, SQLITE_STATIC);
    if( SQLITE_OK!=sqlite3VdbeChangeEncoding(pTos, encoding) ) goto no_mem;
    if( SQLITE_OK!=sqlite3VdbeMemDynamicify(db, pTos) ) goto no_mem;
    pTos->flags &= ~(MEM_Dyn);
    pTos->flags |= MEM_Static;
    if( pOp->p3type==P3_DYNAMIC ){
      sqlite3_free(pOp->p3);
    }
    pOp->p3type = P3_DYNAMIC;
    pOp->p3 = pTos->z;
    pOp->p1 = pTos->n;
    assert( pOp->p1 < SQLITE_MAX_LENGTH ); /* Due to SQLITE_MAX_SQL_LENGTH */
    break;
  }
................................................................................
  pOp->p1 = strlen(pOp->p3)/2;
  assert( SQLITE_MAX_SQL_LENGTH < SQLITE_MAX_LENGTH );
  assert( pOp->p1 < SQLITE_MAX_LENGTH );
  if( pOp->p1 ){
    char *zBlob = sqlite3HexToBlob(pOp->p3);
    if( !zBlob ) goto no_mem;
    if( pOp->p3type==P3_DYNAMIC ){
      sqlite3_free(pOp->p3);
    }
    pOp->p3 = zBlob;
    pOp->p3type = P3_DYNAMIC;
  }else{
    if( pOp->p3type==P3_DYNAMIC ){
      sqlite3_free(pOp->p3);
    }
    pOp->p3type = P3_STATIC;
    pOp->p3 = "";
  }

  /* Fall through to the next case, OP_Blob. */
}
................................................................................
**
** Look at the first P1+2 elements of the stack.  Append them all 
** together with the lowest element first.  The original P1+2 elements
** are popped from the stack if P2==0 and retained if P2==1.  If
** any element of the stack is NULL, then the result is NULL.
**
** When P1==1, this routine makes a copy of the top stack element
** into memory obtained from sqlite3_malloc().
*/
case OP_Concat: {           /* same as TK_CONCAT */
  char *zNew;
  i64 nByte;
  int nField;
  int i, j;
  Mem *pTerm;
................................................................................
  }else{
    /* Otherwise malloc() space for the result and concatenate all the
    ** stack values.
    */
    if( nByte+2>SQLITE_MAX_LENGTH ){
      goto too_big;
    }
    zNew = sqlite3DbMallocRaw(db, nByte+2 );
    if( zNew==0 ) goto no_mem;
    j = 0;
    pTerm = &pTos[1-nField];
    for(i=j=0; i<nField; i++, pTerm++){
      int n = pTerm->n;
      assert( pTerm->flags & (MEM_Str|MEM_Blob) );
      memcpy(&zNew[j], pTerm->z, n);
................................................................................
    assert( pOp[-1].p3type==P3_COLLSEQ );
    assert( pOp[-1].opcode==OP_CollSeq );
    ctx.pColl = (CollSeq *)pOp[-1].p3;
  }
  if( sqlite3SafetyOff(db) ) goto abort_due_to_misuse;
  (*ctx.pFunc->xFunc)(&ctx, n, apVal);
  if( sqlite3SafetyOn(db) ) goto abort_due_to_misuse;
  if( db->mallocFailed ){
    /* Even though a malloc() has failed, the implementation of the
    ** user function may have called an sqlite3_result_XXX() function
    ** to return a value. The following call releases any resources
    ** associated with such a value.
    **
    ** Note: Maybe MemRelease() should be called if sqlite3SafetyOn()
    ** fails also (the if(...) statement above). But if people are
................................................................................
    u8 *zEndHdr;     /* Pointer to first byte after the header */
    u32 offset;      /* Offset into the data */
    int szHdrSz;     /* Size of the header size field at start of record */
    int avail;       /* Number of bytes of available data */

    aType = pC->aType;
    if( aType==0 ){
      pC->aType = aType = sqlite3DbMallocRaw(db, 2*nField*sizeof(aType) );
    }
    if( aType==0 ){
      goto no_mem;
    }
    pC->aOffset = aOffset = &aType[nField];
    pC->payloadSize = payloadSize;
    pC->cacheStatus = p->cacheCtr;
................................................................................
  nByte = nHdr+nData-nZero;
  if( nByte>SQLITE_MAX_LENGTH ){
    goto too_big;
  }

  /* Allocate space for the new record. */
  if( nByte>sizeof(zTemp) ){
    zNewRecord = sqlite3DbMallocRaw(db, nByte);
    if( !zNewRecord ){
      goto no_mem;
    }
  }else{
    zNewRecord = (u8*)zTemp;
  }

................................................................................
    if( pTos->flags & MEM_Null ){
      pTos->z = 0;
      pTos->n = 0;
    }else{
      assert( pTos->flags & (MEM_Blob|MEM_Str) );
    }
    if( pC->pseudoTable ){
      sqlite3_free(pC->pData);
      pC->iKey = iKey;
      pC->nData = pTos->n;
      if( pTos->flags & MEM_Dyn ){
        pC->pData = pTos->z;
        pTos->flags = MEM_Null;
      }else{
        pC->pData = sqlite3_malloc( pC->nData+2 );
        if( !pC->pData ) goto no_mem;
        memcpy(pC->pData, pTos->z, pC->nData);
        pC->pData[pC->nData] = 0;
        pC->pData[pC->nData+1] = 0;
      }
      pC->nullRow = 0;
    }else{
................................................................................
      goto too_big;
    }
    pTos->n = n;
    if( n<=NBFS ){
      pTos->flags = MEM_Blob | MEM_Short;
      pTos->z = pTos->zShort;
    }else{
      char *z = sqlite3_malloc( n );
      if( z==0 ) goto no_mem;
      pTos->flags = MEM_Blob | MEM_Dyn;
      pTos->xDel = 0;
      pTos->z = z;
    }
    if( pC->isIndex ){
      rc = sqlite3BtreeKey(pCrsr, 0, n, pTos->z);
................................................................................
  zSql = sqlite3MPrintf(
     "SELECT name, rootpage, sql FROM '%q'.%s WHERE %s",
     db->aDb[iDb].zName, zMaster, pOp->p3);
  if( zSql==0 ) goto no_mem;
  sqlite3SafetyOff(db);
  assert( db->init.busy==0 );
  db->init.busy = 1;
  assert( !db->mallocFailed );
  rc = sqlite3_exec(db, zSql, sqlite3InitCallback, &initData, 0);
  if( rc==SQLITE_ABORT ) rc = initData.rc;
  sqlite3_free(zSql);
  db->init.busy = 0;
  sqlite3SafetyOn(db);
  if( rc==SQLITE_NOMEM ){

    goto no_mem;
  }
  break;  
}

#if !defined(SQLITE_OMIT_ANALYZE) && !defined(SQLITE_OMIT_PARSER)
/* Opcode: LoadAnalysis P1 * *
................................................................................
  char *z;
  Mem *pnErr;

  for(nRoot=0; &pTos[-nRoot]>=p->aStack; nRoot++){
    if( (pTos[-nRoot].flags & MEM_Int)==0 ) break;
  }
  assert( nRoot>0 );
  aRoot = sqlite3_malloc( sizeof(int)*(nRoot+1) );
  if( aRoot==0 ) goto no_mem;
  j = pOp->p1;
  assert( j>=0 && j<p->nMem );
  pnErr = &p->aMem[j];
  assert( (pnErr->flags & MEM_Int)!=0 );
  for(j=0; j<nRoot; j++){
    aRoot[j] = (pTos-j)->u.i;
................................................................................
    pTos->z = z;
    pTos->n = strlen(z);
    pTos->flags = MEM_Str | MEM_Dyn | MEM_Term;
    pTos->xDel = 0;
  }
  pTos->enc = SQLITE_UTF8;
  sqlite3VdbeChangeEncoding(pTos, encoding);
  sqlite3_free(aRoot);
  break;
}
#endif /* SQLITE_OMIT_INTEGRITY_CHECK */

/* Opcode: FifoWrite * * *
**
** Write the integer on the top of the stack
** into the Fifo.
*/
case OP_FifoWrite: {        /* no-push */
  assert( pTos>=p->aStack );
  sqlite3VdbeMemIntegerify(pTos);
  if( sqlite3VdbeFifoPush(&p->sFifo, pTos->u.i)==SQLITE_NOMEM ){
    goto nomem;
  }
  assert( (pTos->flags & MEM_Dyn)==0 );
  pTos--;
  break;
}

/* Opcode: FifoRead * P2 *
**
................................................................................
  int i = p->contextStackTop++;
  Context *pContext;

  assert( i>=0 );
  /* FIX ME: This should be allocated as part of the vdbe at compile-time */
  if( i>=p->contextStackDepth ){
    p->contextStackDepth = i+1;
    p->contextStack = sqlite3ReallocOrFree(db, p->contextStack,
                                          sizeof(Context)*(i+1));
    if( p->contextStack==0 ) goto no_mem;
  }
  pContext = &p->contextStack[i];
  pContext->lastRowid = db->lastRowid;
  pContext->nChange = p->nChange;
  pContext->sFifo = p->sFifo;
................................................................................
  ctx.pMem = pMem = &p->aMem[pOp->p1];
  pMem->n++;
  ctx.s.flags = MEM_Null;
  ctx.s.z = 0;
  ctx.s.xDel = 0;
  ctx.isError = 0;
  ctx.pColl = 0;
  ctx.db = db;
  if( ctx.pFunc->needCollSeq ){
    assert( pOp>p->aOp );
    assert( pOp[-1].p3type==P3_COLLSEQ );
    assert( pOp[-1].opcode==OP_CollSeq );
    ctx.pColl = (CollSeq *)pOp[-1].p3;
  }
  (ctx.pFunc->xStep)(&ctx, n, apVal);
................................................................................

    /* Initialise vdbe cursor object */
    pCur = allocateCursor(p, pOp->p1, -1);
    if( pCur ){
      pCur->pVtabCursor = pVtabCursor;
      pCur->pModule = pVtabCursor->pVtab->pModule;
    }else{
      db->mallocFailed = 1;
      pModule->xClose(pVtabCursor);
    }
  }
  break;
}
#endif /* SQLITE_OMIT_VIRTUALTABLE */

................................................................................
  sqlite3SetString(&p->zErrMsg, "string or blob too big", (char*)0);
  rc = SQLITE_TOOBIG;
  goto vdbe_halt;

  /* Jump to here if a malloc() fails.
  */
no_mem:
  db->mallocFailed = 1;
  sqlite3SetString(&p->zErrMsg, "out of memory", (char*)0);
  rc = SQLITE_NOMEM;
  goto vdbe_halt;

  /* Jump to here for an SQLITE_MISUSE error.
  */
abort_due_to_misuse:
................................................................................
  /* Fall thru into abort_due_to_error */

  /* Jump to here for any other kind of fatal error.  The "rc" variable
  ** should hold the error number.
  */
abort_due_to_error:
  if( p->zErrMsg==0 ){
    if( db->mallocFailed ) rc = SQLITE_NOMEM;
    sqlite3SetString(&p->zErrMsg, sqlite3ErrStr(rc), (char*)0);
  }
  goto vdbe_halt;

  /* Jump to here if the sqlite3_interrupt() API sets the interrupt
  ** flag.
  */

struct sqlite3_context {
  FuncDef *pFunc;       /* Pointer to function information.  MUST BE FIRST */
  VdbeFunc *pVdbeFunc;  /* Auxilary data, if created. */
  Mem s;                /* The return value is stored here */
  Mem *pMem;            /* Memory cell used to store aggregate context */
  u8 isError;           /* Set to true for an error */
  CollSeq *pColl;       /* Collating sequence */

};

/*
** A Set structure is used for quick testing to see if a value
** is part of a small set.  Sets are used to implement code like
** this:
**            x.y IN ('hi','hoo','hum')
................................................................................
#define VDBE_MAGIC_RUN      0xbdf20da3    /* VDBE is ready to execute */
#define VDBE_MAGIC_HALT     0x519c2973    /* VDBE has completed execution */
#define VDBE_MAGIC_DEAD     0xb606c3c8    /* The VDBE has been deallocated */

/*
** Function prototypes
*/

void sqlite3VdbeFreeCursor(Vdbe *, Cursor*);
void sqliteVdbePopStack(Vdbe*,int);
int sqlite3VdbeCursorMoveto(Cursor*);
#if defined(SQLITE_DEBUG) || defined(VDBE_PROFILE)
void sqlite3VdbePrintOp(FILE*, int, Op*);
#endif
int sqlite3VdbeSerialTypeLen(u32);

struct sqlite3_context {
  FuncDef *pFunc;       /* Pointer to function information.  MUST BE FIRST */
  VdbeFunc *pVdbeFunc;  /* Auxilary data, if created. */
  Mem s;                /* The return value is stored here */
  Mem *pMem;            /* Memory cell used to store aggregate context */
  u8 isError;           /* Set to true for an error */
  CollSeq *pColl;       /* Collating sequence */
  sqlite3 *db;          /* Database connection */
};

/*
** A Set structure is used for quick testing to see if a value
** is part of a small set.  Sets are used to implement code like
** this:
**            x.y IN ('hi','hoo','hum')
................................................................................
#define VDBE_MAGIC_RUN      0xbdf20da3    /* VDBE is ready to execute */
#define VDBE_MAGIC_HALT     0x519c2973    /* VDBE has completed execution */
#define VDBE_MAGIC_DEAD     0xb606c3c8    /* The VDBE has been deallocated */

/*
** Function prototypes
*/
sqlite3 *sqlite3DbOfVdbe(Vdbe*);
void sqlite3VdbeFreeCursor(Vdbe *, Cursor*);
void sqliteVdbePopStack(Vdbe*,int);
int sqlite3VdbeCursorMoveto(Cursor*);
#if defined(SQLITE_DEBUG) || defined(VDBE_PROFILE)
void sqlite3VdbePrintOp(FILE*, int, Op*);
#endif
int sqlite3VdbeSerialTypeLen(u32);

** outer sqlite3_step() wrapper procedure.
*/
static int sqlite3Step(Vdbe *p){
  sqlite3 *db;
  int rc;

  /* Assert that malloc() has not failed */
  assert( !sqlite3MallocFailed() );


  if( p==0 || p->magic!=VDBE_MAGIC_RUN ){
    return SQLITE_MISUSE;
  }
  if( p->aborted ){
    return SQLITE_ABORT;
  }
................................................................................
  if( p->pc<=0 && p->expired ){
    if( p->rc==SQLITE_OK ){
      p->rc = SQLITE_SCHEMA;
    }
    rc = SQLITE_ERROR;
    goto end_of_step;
  }
  db = p->db;
  if( sqlite3SafetyOn(db) ){
    p->rc = SQLITE_MISUSE;
    return SQLITE_MISUSE;
  }
  if( p->pc<0 ){
    /* If there are no other statements currently running, then
    ** reset the interrupt flag.  This prevents a call to sqlite3_interrupt
................................................................................
      pMem->flags = MEM_Agg;
      pMem->xDel = sqlite3FreeX;
      pMem->u.pDef = p->pFunc;
      if( nByte<=NBFS ){
        pMem->z = pMem->zShort;
        memset(pMem->z, 0, nByte);
      }else{
        pMem->z = sqliteMalloc( nByte );
      }
    }
  }
  return (void*)pMem->z;
}

/*
................................................................................
  struct AuxData *pAuxData;
  VdbeFunc *pVdbeFunc;
  if( iArg<0 ) goto failed;

  pVdbeFunc = pCtx->pVdbeFunc;
  if( !pVdbeFunc || pVdbeFunc->nAux<=iArg ){
    int nMalloc = sizeof(VdbeFunc) + sizeof(struct AuxData)*iArg;
    pVdbeFunc = sqliteRealloc(pVdbeFunc, nMalloc);
    if( !pVdbeFunc ) goto failed;



    pCtx->pVdbeFunc = pVdbeFunc;
    memset(&pVdbeFunc->apAux[pVdbeFunc->nAux], 0, 
             sizeof(struct AuxData)*(iArg+1-pVdbeFunc->nAux));
    pVdbeFunc->nAux = iArg+1;
    pVdbeFunc->pFunc = pCtx->pFunc;
  }

** outer sqlite3_step() wrapper procedure.
*/
static int sqlite3Step(Vdbe *p){
  sqlite3 *db;
  int rc;

  /* Assert that malloc() has not failed */
  db = p->db;
  assert( !db->mallocFailed );

  if( p==0 || p->magic!=VDBE_MAGIC_RUN ){
    return SQLITE_MISUSE;
  }
  if( p->aborted ){
    return SQLITE_ABORT;
  }
................................................................................
  if( p->pc<=0 && p->expired ){
    if( p->rc==SQLITE_OK ){
      p->rc = SQLITE_SCHEMA;
    }
    rc = SQLITE_ERROR;
    goto end_of_step;
  }

  if( sqlite3SafetyOn(db) ){
    p->rc = SQLITE_MISUSE;
    return SQLITE_MISUSE;
  }
  if( p->pc<0 ){
    /* If there are no other statements currently running, then
    ** reset the interrupt flag.  This prevents a call to sqlite3_interrupt
................................................................................
      pMem->flags = MEM_Agg;
      pMem->xDel = sqlite3FreeX;
      pMem->u.pDef = p->pFunc;
      if( nByte<=NBFS ){
        pMem->z = pMem->zShort;
        memset(pMem->z, 0, nByte);
      }else{
        pMem->z = sqlite3DbMallocZero(p->db, nByte);
      }
    }
  }
  return (void*)pMem->z;
}

/*
................................................................................
  struct AuxData *pAuxData;
  VdbeFunc *pVdbeFunc;
  if( iArg<0 ) goto failed;

  pVdbeFunc = pCtx->pVdbeFunc;
  if( !pVdbeFunc || pVdbeFunc->nAux<=iArg ){
    int nMalloc = sizeof(VdbeFunc) + sizeof(struct AuxData)*iArg;
    pVdbeFunc = sqlite3_realloc(pVdbeFunc, nMalloc);
    if( !pVdbeFunc ){
      pCtx->db->mallocFailed = 1;
      goto failed;
    }
    pCtx->pVdbeFunc = pVdbeFunc;
    memset(&pVdbeFunc->apAux[pVdbeFunc->nAux], 0, 
             sizeof(struct AuxData)*(iArg+1-pVdbeFunc->nAux));
    pVdbeFunc->nAux = iArg+1;
    pVdbeFunc->pFunc = pCtx->pFunc;
  }

** set the sqlite3_vdbe_addop_trace to 1 and all opcodes will be printed
** as they are added to the instruction stream.
*/
#ifdef SQLITE_DEBUG
int sqlite3_vdbe_addop_trace = 0;
#endif









/*
** Create a new virtual database engine.
*/
Vdbe *sqlite3VdbeCreate(sqlite3 *db){
  Vdbe *p;
  p = sqliteMalloc( sizeof(Vdbe) );
  if( p==0 ) return 0;
  p->db = db;
  if( db->pVdbe ){
    db->pVdbe->pPrev = p;
  }
  p->pNext = db->pVdbe;
  p->pPrev = 0;
................................................................................

/*
** Remember the SQL string for a prepared statement.
*/
void sqlite3VdbeSetSql(Vdbe *p, const char *z, int n){
  if( p==0 ) return;
  assert( p->zSql==0 );
  p->zSql = sqlite3StrNDup(z, n);
}

/*
** Return the SQL associated with a prepared statement
*/
const char *sqlite3VdbeGetSql(Vdbe *p){
  return p->zSql;
................................................................................
*/
static void resizeOpArray(Vdbe *p, int N){
  int runMode = p->magic==VDBE_MAGIC_RUN;
  if( runMode || p->nOpAlloc<N ){
    VdbeOp *pNew;
    int nNew = N + 100*(!runMode);
    int oldSize = p->nOpAlloc;
    pNew = sqliteRealloc(p->aOp, nNew*sizeof(Op));
    if( pNew ){
      p->nOpAlloc = nNew;
      p->aOp = pNew;
      if( nNew>oldSize ){
        memset(&p->aOp[oldSize], 0, (nNew-oldSize)*sizeof(Op));
      }


    }
  }
}

/*
** Add a new instruction to the list of instructions current in the
** VDBE.  Return the address of the new instruction.
................................................................................
  int i;
  VdbeOp *pOp;

  i = p->nOp;
  assert( p->magic==VDBE_MAGIC_INIT );
  if( p->nOpAlloc<=i ){
    resizeOpArray(p, i+1);
    if( sqlite3MallocFailed() ){
      return 0;
    }
  }
  p->nOp++;
  pOp = &p->aOp[i];
  pOp->opcode = op;
  pOp->p1 = p1;
................................................................................
*/
int sqlite3VdbeMakeLabel(Vdbe *p){
  int i;
  i = p->nLabel++;
  assert( p->magic==VDBE_MAGIC_INIT );
  if( i>=p->nLabelAlloc ){
    p->nLabelAlloc = p->nLabelAlloc*2 + 10;
    p->aLabel = sqliteReallocOrFree(p->aLabel,
                                    p->nLabelAlloc*sizeof(p->aLabel[0]));
  }
  if( p->aLabel ){
    p->aLabel[i] = -1;
  }
  return -1-i;
}
................................................................................
      nMaxStack--;
    }

    if( pOp->p2>=0 ) continue;
    assert( -1-pOp->p2<p->nLabel );
    pOp->p2 = aLabel[-1-pOp->p2];
  }
  sqliteFree(p->aLabel);
  p->aLabel = 0;

  *pMaxFuncArgs = nMaxArgs;
  *pMaxStack = nMaxStack;

  /* If we never rollback a statement transaction, then statement
  ** transactions are not needed.  So change every OP_Statement
................................................................................
** Add a whole list of operations to the operation stack.  Return the
** address of the first operation added.
*/
int sqlite3VdbeAddOpList(Vdbe *p, int nOp, VdbeOpList const *aOp){
  int addr;
  assert( p->magic==VDBE_MAGIC_INIT );
  resizeOpArray(p, p->nOp + nOp);
  if( sqlite3MallocFailed() ){
    return 0;
  }
  addr = p->nOp;
  if( nOp>0 ){
    int i;
    VdbeOpList const *pIn = aOp;
    for(i=0; i<nOp; i++, pIn++){
................................................................................

/*
** If the input FuncDef structure is ephemeral, then free it.  If
** the FuncDef is not ephermal, then do nothing.
*/
static void freeEphemeralFunction(FuncDef *pDef){
  if( pDef && (pDef->flags & SQLITE_FUNC_EPHEM)!=0 ){
    sqliteFree(pDef);
  }
}

/*
** Delete a P3 value if necessary.
*/
static void freeP3(int p3type, void *p3){
  if( p3 ){
    switch( p3type ){
      case P3_DYNAMIC:
      case P3_KEYINFO:
      case P3_KEYINFO_HANDOFF: {
        sqliteFree(p3);
        break;
      }
      case P3_MPRINTF: {
        sqlite3_free(p3);
        break;
      }
      case P3_VDBEFUNC: {
        VdbeFunc *pVdbeFunc = (VdbeFunc *)p3;
        freeEphemeralFunction(pVdbeFunc->pFunc);
        sqlite3VdbeDeleteAuxData(pVdbeFunc, 0);
        sqliteFree(pVdbeFunc);
        break;
      }
      case P3_FUNCDEF: {
        freeEphemeralFunction((FuncDef*)p3);
        break;
      }
      case P3_MEM: {
................................................................................
/*
** Change the value of the P3 operand for a specific instruction.
** This routine is useful when a large program is loaded from a
** static array using sqlite3VdbeAddOpList but we want to make a
** few minor changes to the program.
**
** If n>=0 then the P3 operand is dynamic, meaning that a copy of
** the string is made into memory obtained from sqliteMalloc().
** A value of n==0 means copy bytes of zP3 up to and including the
** first null byte.  If n>0 then copy n+1 bytes of zP3.
**
** If n==P3_KEYINFO it means that zP3 is a pointer to a KeyInfo structure.
** A copy is made of the KeyInfo structure into memory obtained from
** sqliteMalloc, to be freed when the Vdbe is finalized.
** n==P3_KEYINFO_HANDOFF indicates that zP3 points to a KeyInfo structure
** stored in memory that the caller has obtained from sqliteMalloc. The 
** caller should not free the allocation, it will be freed when the Vdbe is
** finalized.
** 
** Other values of n (P3_STATIC, P3_COLLSEQ etc.) indicate that zP3 points
** to a string or structure that is guaranteed to exist for the lifetime of
** the Vdbe. In these cases we can just copy the pointer.
**
** If addr<0 then change P3 on the most recently inserted instruction.
*/
void sqlite3VdbeChangeP3(Vdbe *p, int addr, const char *zP3, int n){
  Op *pOp;
  assert( p==0 || p->magic==VDBE_MAGIC_INIT );
  if( p==0 || p->aOp==0 || sqlite3MallocFailed() ){
    if (n != P3_KEYINFO) {
      freeP3(n, (void*)*(char**)&zP3);
    }
    return;
  }
  if( addr<0 || addr>=p->nOp ){
    addr = p->nOp - 1;
................................................................................
    pOp->p3type = P3_NOTUSED;
  }else if( n==P3_KEYINFO ){
    KeyInfo *pKeyInfo;
    int nField, nByte;

    nField = ((KeyInfo*)zP3)->nField;
    nByte = sizeof(*pKeyInfo) + (nField-1)*sizeof(pKeyInfo->aColl[0]) + nField;
    pKeyInfo = sqliteMallocRaw( nByte );
    pOp->p3 = (char*)pKeyInfo;
    if( pKeyInfo ){
      unsigned char *aSortOrder;
      memcpy(pKeyInfo, zP3, nByte);
      aSortOrder = pKeyInfo->aSortOrder;
      if( aSortOrder ){
        pKeyInfo->aSortOrder = (unsigned char*)&pKeyInfo->aColl[nField];
        memcpy(pKeyInfo->aSortOrder, aSortOrder, nField);
      }
      pOp->p3type = P3_KEYINFO;
    }else{

      pOp->p3type = P3_NOTUSED;
    }
  }else if( n==P3_KEYINFO_HANDOFF ){
    pOp->p3 = (char*)zP3;
    pOp->p3type = P3_KEYINFO;
  }else if( n<0 ){
    pOp->p3 = (char*)zP3;
    pOp->p3type = n;
  }else{
    if( n==0 ) n = strlen(zP3);
    pOp->p3 = sqliteStrNDup(zP3, n);
    pOp->p3type = P3_DYNAMIC;
  }
}

#ifndef NDEBUG
/*
** Replace the P3 field of the most recently coded instruction with
** comment text.
*/
void sqlite3VdbeComment(Vdbe *p, const char *zFormat, ...){
  va_list ap;
  assert( p->nOp>0 || p->aOp==0 );
  assert( p->aOp==0 || p->aOp[p->nOp-1].p3==0 || sqlite3MallocFailed() );
  va_start(ap, zFormat);
  sqlite3VdbeChangeP3(p, -1, sqlite3VMPrintf(zFormat, ap), P3_DYNAMIC);
  va_end(ap);
}
#endif

/*
** Return the opcode for a given address.
*/
VdbeOp *sqlite3VdbeGetOp(Vdbe *p, int addr){
  assert( p->magic==VDBE_MAGIC_INIT );
  assert( (addr>=0 && addr<p->nOp) || sqlite3MallocFailed() );
  return ((addr>=0 && addr<p->nOp)?(&p->aOp[addr]):0);
}

#if !defined(SQLITE_OMIT_EXPLAIN) || !defined(NDEBUG) \
     || defined(VDBE_PROFILE) || defined(SQLITE_DEBUG)
/*
** Compute a string that describes the P3 parameter for an opcode.
................................................................................
    resolveP2Values(p, &nArg, &nStack);
    resizeOpArray(p, p->nOp);
    assert( nVar>=0 );
    assert( nStack<p->nOp );
    if( isExplain ){
      nStack = 10;
    }
    p->aStack = sqliteMalloc(
        nStack*sizeof(p->aStack[0])    /* aStack */
      + nArg*sizeof(Mem*)              /* apArg */
      + nVar*sizeof(Mem)               /* aVar */
      + nVar*sizeof(char*)             /* azVar */
      + nMem*sizeof(Mem)               /* aMem */
      + nCursor*sizeof(Cursor*)        /* apCsr */
    );
    if( !sqlite3MallocFailed() ){
      p->aMem = &p->aStack[nStack];
      p->nMem = nMem;
      p->aVar = &p->aMem[nMem];
      p->nVar = nVar;
      p->okVar = 0;
      p->apArg = (Mem**)&p->aVar[nVar];
      p->azVar = (char**)&p->apArg[nArg];
................................................................................
    p->inVtabMethod = 1;
    sqlite3SafetyOff(p->db);
    pModule->xClose(pVtabCursor);
    sqlite3SafetyOn(p->db);
    p->inVtabMethod = 0;
  }
#endif
  sqliteFree(pCx->pData);
  sqliteFree(pCx->aType);
  sqliteFree(pCx);
}

/*
** Close all cursors
*/
static void closeAllCursors(Vdbe *p){
  int i;
................................................................................
  closeAllCursors(p);
  releaseMemArray(p->aMem, p->nMem);
  sqlite3VdbeFifoClear(&p->sFifo);
  if( p->contextStack ){
    for(i=0; i<p->contextStackTop; i++){
      sqlite3VdbeFifoClear(&p->contextStack[i].sFifo);
    }
    sqliteFree(p->contextStack);
  }
  p->contextStack = 0;
  p->contextStackDepth = 0;
  p->contextStackTop = 0;
  sqliteFree(p->zErrMsg);
  p->zErrMsg = 0;
  p->resOnStack = 0;
}

/*
** Set the number of result columns that will be returned by this SQL
** statement. This is now set at compile time, rather than during
................................................................................
** execution of the vdbe program so that sqlite3_column_count() can
** be called on an SQL statement before sqlite3_step().
*/
void sqlite3VdbeSetNumCols(Vdbe *p, int nResColumn){
  Mem *pColName;
  int n;
  releaseMemArray(p->aColName, p->nResColumn*COLNAME_N);
  sqliteFree(p->aColName);
  n = nResColumn*COLNAME_N;
  p->nResColumn = nResColumn;
  p->aColName = pColName = (Mem*)sqliteMalloc( sizeof(Mem)*n );
  if( p->aColName==0 ) return;
  while( n-- > 0 ){
    (pColName++)->flags = MEM_Null;
  }
}

/*
................................................................................
** Set the name of the idx'th column to be returned by the SQL statement.
** zName must be a pointer to a nul terminated string.
**
** This call must be made after a call to sqlite3VdbeSetNumCols().
**
** If N==P3_STATIC  it means that zName is a pointer to a constant static
** string and we can just copy the pointer. If it is P3_DYNAMIC, then 
** the string is freed using sqliteFree() when the vdbe is finished with
** it. Otherwise, N bytes of zName are copied.
*/
int sqlite3VdbeSetColName(Vdbe *p, int idx, int var, const char *zName, int N){
  int rc;
  Mem *pColName;
  assert( idx<p->nResColumn );
  assert( var<COLNAME_N );
  if( sqlite3MallocFailed() ) return SQLITE_NOMEM;
  assert( p->aColName!=0 );
  pColName = &(p->aColName[idx+var*p->nResColumn]);
  if( N==P3_DYNAMIC || N==P3_STATIC ){
    rc = sqlite3VdbeMemSetStr(pColName, zName, -1, SQLITE_UTF8, SQLITE_STATIC);
  }else{
    rc = sqlite3VdbeMemSetStr(pColName, zName, N, SQLITE_UTF8,SQLITE_TRANSIENT);
  }
................................................................................
    char const *zMainFile = sqlite3BtreeGetFilename(db->aDb[0].pBt);
    sqlite3_file *master = 0;
    i64 offset = 0;

    /* Select a master journal file name */
    do {
      u32 random;
      sqliteFree(zMaster);
      sqlite3Randomness(sizeof(random), &random);
      zMaster = sqlite3MPrintf("%s-mj%08X", zMainFile, random&0x7fffffff);
      if( !zMaster ){
        return SQLITE_NOMEM;
      }
    }while( sqlite3OsFileExists(zMaster) );

    /* Open the master journal. */
    rc = sqlite3OsOpenExclusive(zMaster, &master, 0);
    if( rc!=SQLITE_OK ){
      sqliteFree(zMaster);
      return rc;
    }
 
    /* Write the name of each database file in the transaction into the new
    ** master journal file. If an error occurs at this point close
    ** and delete the master journal file. All the individual journal files
    ** still have 'null' as the master journal pointer, so they will roll
................................................................................
          needSync = 1;
        }
        rc = sqlite3OsWrite(master, zFile, strlen(zFile)+1, offset);
        offset += strlen(zFile)+1;
        if( rc!=SQLITE_OK ){
          sqlite3OsClose(&master);
          sqlite3OsDelete(zMaster);
          sqliteFree(zMaster);
          return rc;
        }
      }
    }


    /* Sync the master journal file. Before doing this, open the directory
................................................................................
    zMainFile = sqlite3BtreeGetDirname(db->aDb[0].pBt);
#if 0
    rc = sqlite3OsOpenDirectory(master, zMainFile);
    if( rc!=SQLITE_OK ||
          (needSync && (rc=sqlite3OsSync(master,0))!=SQLITE_OK) ){
      sqlite3OsClose(&master);
      sqlite3OsDelete(zMaster);
      sqliteFree(zMaster);
      return rc;
    }
#endif

    /* Sync all the db files involved in the transaction. The same call
    ** sets the master journal pointer in each individual journal. If
    ** an error occurs here, do not delete the master journal file.
................................................................................
      Btree *pBt = db->aDb[i].pBt;
      if( pBt && sqlite3BtreeIsInTrans(pBt) ){
        rc = sqlite3BtreeCommitPhaseOne(pBt, zMaster);
      }
    }
    sqlite3OsClose(&master);
    if( rc!=SQLITE_OK ){
      sqliteFree(zMaster);
      return rc;
    }

    /* Delete the master journal file. This commits the transaction. After
    ** doing this the directory is synced again before any individual
    ** transaction files are deleted.
    */
    rc = sqlite3OsDelete(zMaster);
    sqliteFree(zMaster);
    zMaster = 0;
    if( rc ){
      return rc;
    }
    rc = sqlite3OsSyncDirectory(zMainFile);
    if( rc!=SQLITE_OK ){
      /* This is not good. The master journal file has been deleted, but
................................................................................
  **
  ** Other errors:
  **
  ** No error:
  **
  */

  if( sqlite3MallocFailed() ){
    p->rc = SQLITE_NOMEM;
  }
  if( p->magic!=VDBE_MAGIC_RUN ){
    /* Already halted.  Nothing to do. */
    assert( p->magic==VDBE_MAGIC_HALT );
#ifndef SQLITE_OMIT_VIRTUALTABLE
    closeAllCursors(p);
................................................................................
    p->pNext->pPrev = p->pPrev;
  }
  if( p->aOp ){
    for(i=0; i<p->nOp; i++){
      Op *pOp = &p->aOp[i];
      freeP3(pOp->p3type, pOp->p3);
    }
    sqliteFree(p->aOp);
  }
  releaseMemArray(p->aVar, p->nVar);
  sqliteFree(p->aLabel);
  sqliteFree(p->aStack);
  releaseMemArray(p->aColName, p->nResColumn*COLNAME_N);
  sqliteFree(p->aColName);
  sqliteFree(p->zSql);
  p->magic = VDBE_MAGIC_DEAD;
  sqliteFree(p);
}

/*
** If a MoveTo operation is pending on the given cursor, then do that
** MoveTo now.  Return an error code.  If no MoveTo is pending, this
** routine does nothing and returns SQLITE_OK.
*/

** set the sqlite3_vdbe_addop_trace to 1 and all opcodes will be printed
** as they are added to the instruction stream.
*/
#ifdef SQLITE_DEBUG
int sqlite3_vdbe_addop_trace = 0;
#endif

/*
** Return the database connection associated with a VDBE
*/
sqlite3 *sqlite3DbOfVdbe(Vdbe *p){
  return p->db;
}


/*
** Create a new virtual database engine.
*/
Vdbe *sqlite3VdbeCreate(sqlite3 *db){
  Vdbe *p;
  p = sqlite3DbMallocZero(db, sizeof(Vdbe) );
  if( p==0 ) return 0;
  p->db = db;
  if( db->pVdbe ){
    db->pVdbe->pPrev = p;
  }
  p->pNext = db->pVdbe;
  p->pPrev = 0;
................................................................................

/*
** Remember the SQL string for a prepared statement.
*/
void sqlite3VdbeSetSql(Vdbe *p, const char *z, int n){
  if( p==0 ) return;
  assert( p->zSql==0 );
  p->zSql = sqlite3DbStrNDup(p->db, z, n);
}

/*
** Return the SQL associated with a prepared statement
*/
const char *sqlite3VdbeGetSql(Vdbe *p){
  return p->zSql;
................................................................................
*/
static void resizeOpArray(Vdbe *p, int N){
  int runMode = p->magic==VDBE_MAGIC_RUN;
  if( runMode || p->nOpAlloc<N ){
    VdbeOp *pNew;
    int nNew = N + 100*(!runMode);
    int oldSize = p->nOpAlloc;
    pNew = sqlite_realloc(p->aOp, nNew*sizeof(Op));
    if( pNew ){
      p->nOpAlloc = nNew;
      p->aOp = pNew;
      if( nNew>oldSize ){
        memset(&p->aOp[oldSize], 0, (nNew-oldSize)*sizeof(Op));
      }
    }else{
      p->db->mallocFailed = 1;
    }
  }
}

/*
** Add a new instruction to the list of instructions current in the
** VDBE.  Return the address of the new instruction.
................................................................................
  int i;
  VdbeOp *pOp;

  i = p->nOp;
  assert( p->magic==VDBE_MAGIC_INIT );
  if( p->nOpAlloc<=i ){
    resizeOpArray(p, i+1);
    if( p->db->mallocFailed ){
      return 0;
    }
  }
  p->nOp++;
  pOp = &p->aOp[i];
  pOp->opcode = op;
  pOp->p1 = p1;
................................................................................
*/
int sqlite3VdbeMakeLabel(Vdbe *p){
  int i;
  i = p->nLabel++;
  assert( p->magic==VDBE_MAGIC_INIT );
  if( i>=p->nLabelAlloc ){
    p->nLabelAlloc = p->nLabelAlloc*2 + 10;
    p->aLabel = sqlite3ReallocOrFree(p->db, p->aLabel,
                                    p->nLabelAlloc*sizeof(p->aLabel[0]));
  }
  if( p->aLabel ){
    p->aLabel[i] = -1;
  }
  return -1-i;
}
................................................................................
      nMaxStack--;
    }

    if( pOp->p2>=0 ) continue;
    assert( -1-pOp->p2<p->nLabel );
    pOp->p2 = aLabel[-1-pOp->p2];
  }
  sqlite3_free(p->aLabel);
  p->aLabel = 0;

  *pMaxFuncArgs = nMaxArgs;
  *pMaxStack = nMaxStack;

  /* If we never rollback a statement transaction, then statement
  ** transactions are not needed.  So change every OP_Statement
................................................................................
** Add a whole list of operations to the operation stack.  Return the
** address of the first operation added.
*/
int sqlite3VdbeAddOpList(Vdbe *p, int nOp, VdbeOpList const *aOp){
  int addr;
  assert( p->magic==VDBE_MAGIC_INIT );
  resizeOpArray(p, p->nOp + nOp);
  if( p->db->mallocFailed ){
    return 0;
  }
  addr = p->nOp;
  if( nOp>0 ){
    int i;
    VdbeOpList const *pIn = aOp;
    for(i=0; i<nOp; i++, pIn++){
................................................................................

/*
** If the input FuncDef structure is ephemeral, then free it.  If
** the FuncDef is not ephermal, then do nothing.
*/
static void freeEphemeralFunction(FuncDef *pDef){
  if( pDef && (pDef->flags & SQLITE_FUNC_EPHEM)!=0 ){
    sqlite3_free(pDef);
  }
}

/*
** Delete a P3 value if necessary.
*/
static void freeP3(int p3type, void *p3){
  if( p3 ){
    switch( p3type ){
      case P3_DYNAMIC:
      case P3_KEYINFO:
      case P3_KEYINFO_HANDOFF: {
        sqlite3_free(p3);
        break;
      }
      case P3_MPRINTF: {
        sqlite3_free(p3);
        break;
      }
      case P3_VDBEFUNC: {
        VdbeFunc *pVdbeFunc = (VdbeFunc *)p3;
        freeEphemeralFunction(pVdbeFunc->pFunc);
        sqlite3VdbeDeleteAuxData(pVdbeFunc, 0);
        sqlite3_free(pVdbeFunc);
        break;
      }
      case P3_FUNCDEF: {
        freeEphemeralFunction((FuncDef*)p3);
        break;
      }
      case P3_MEM: {
................................................................................
/*
** Change the value of the P3 operand for a specific instruction.
** This routine is useful when a large program is loaded from a
** static array using sqlite3VdbeAddOpList but we want to make a
** few minor changes to the program.
**
** If n>=0 then the P3 operand is dynamic, meaning that a copy of
** the string is made into memory obtained from sqlite3_malloc().
** A value of n==0 means copy bytes of zP3 up to and including the
** first null byte.  If n>0 then copy n+1 bytes of zP3.
**
** If n==P3_KEYINFO it means that zP3 is a pointer to a KeyInfo structure.
** A copy is made of the KeyInfo structure into memory obtained from
** sqlite3_malloc, to be freed when the Vdbe is finalized.
** n==P3_KEYINFO_HANDOFF indicates that zP3 points to a KeyInfo structure
** stored in memory that the caller has obtained from sqlite3_malloc. The 
** caller should not free the allocation, it will be freed when the Vdbe is
** finalized.
** 
** Other values of n (P3_STATIC, P3_COLLSEQ etc.) indicate that zP3 points
** to a string or structure that is guaranteed to exist for the lifetime of
** the Vdbe. In these cases we can just copy the pointer.
**
** If addr<0 then change P3 on the most recently inserted instruction.
*/
void sqlite3VdbeChangeP3(Vdbe *p, int addr, const char *zP3, int n){
  Op *pOp;
  assert( p==0 || p->magic==VDBE_MAGIC_INIT );
  if( p==0 || p->aOp==0 || p->db->mallocFailed ){
    if (n != P3_KEYINFO) {
      freeP3(n, (void*)*(char**)&zP3);
    }
    return;
  }
  if( addr<0 || addr>=p->nOp ){
    addr = p->nOp - 1;
................................................................................
    pOp->p3type = P3_NOTUSED;
  }else if( n==P3_KEYINFO ){
    KeyInfo *pKeyInfo;
    int nField, nByte;

    nField = ((KeyInfo*)zP3)->nField;
    nByte = sizeof(*pKeyInfo) + (nField-1)*sizeof(pKeyInfo->aColl[0]) + nField;
    pKeyInfo = sqlite3_malloc( nByte );
    pOp->p3 = (char*)pKeyInfo;
    if( pKeyInfo ){
      unsigned char *aSortOrder;
      memcpy(pKeyInfo, zP3, nByte);
      aSortOrder = pKeyInfo->aSortOrder;
      if( aSortOrder ){
        pKeyInfo->aSortOrder = (unsigned char*)&pKeyInfo->aColl[nField];
        memcpy(pKeyInfo->aSortOrder, aSortOrder, nField);
      }
      pOp->p3type = P3_KEYINFO;
    }else{
      p->db->mallocFailed = 1;
      pOp->p3type = P3_NOTUSED;
    }
  }else if( n==P3_KEYINFO_HANDOFF ){
    pOp->p3 = (char*)zP3;
    pOp->p3type = P3_KEYINFO;
  }else if( n<0 ){
    pOp->p3 = (char*)zP3;
    pOp->p3type = n;
  }else{
    if( n==0 ) n = strlen(zP3);
    pOp->p3 = sqlite3DbStrNDup(p->db, zP3, n);
    pOp->p3type = P3_DYNAMIC;
  }
}

#ifndef NDEBUG
/*
** Replace the P3 field of the most recently coded instruction with
** comment text.
*/
void sqlite3VdbeComment(Vdbe *p, const char *zFormat, ...){
  va_list ap;
  assert( p->nOp>0 || p->aOp==0 );
  assert( p->aOp==0 || p->aOp[p->nOp-1].p3==0 || p->db->mallocFailed );
  va_start(ap, zFormat);
  sqlite3VdbeChangeP3(p, -1, sqlite3VMPrintf(zFormat, ap), P3_DYNAMIC);
  va_end(ap);
}
#endif

/*
** Return the opcode for a given address.
*/
VdbeOp *sqlite3VdbeGetOp(Vdbe *p, int addr){
  assert( p->magic==VDBE_MAGIC_INIT );
  assert( (addr>=0 && addr<p->nOp) || p->db->mallocFailed );
  return ((addr>=0 && addr<p->nOp)?(&p->aOp[addr]):0);
}

#if !defined(SQLITE_OMIT_EXPLAIN) || !defined(NDEBUG) \
     || defined(VDBE_PROFILE) || defined(SQLITE_DEBUG)
/*
** Compute a string that describes the P3 parameter for an opcode.
................................................................................
    resolveP2Values(p, &nArg, &nStack);
    resizeOpArray(p, p->nOp);
    assert( nVar>=0 );
    assert( nStack<p->nOp );
    if( isExplain ){
      nStack = 10;
    }
    p->aStack = sqlite3DbMallocZer(db,
        nStack*sizeof(p->aStack[0])    /* aStack */
      + nArg*sizeof(Mem*)              /* apArg */
      + nVar*sizeof(Mem)               /* aVar */
      + nVar*sizeof(char*)             /* azVar */
      + nMem*sizeof(Mem)               /* aMem */
      + nCursor*sizeof(Cursor*)        /* apCsr */
    );
    if( !db->mallocFailed ){
      p->aMem = &p->aStack[nStack];
      p->nMem = nMem;
      p->aVar = &p->aMem[nMem];
      p->nVar = nVar;
      p->okVar = 0;
      p->apArg = (Mem**)&p->aVar[nVar];
      p->azVar = (char**)&p->apArg[nArg];
................................................................................
    p->inVtabMethod = 1;
    sqlite3SafetyOff(p->db);
    pModule->xClose(pVtabCursor);
    sqlite3SafetyOn(p->db);
    p->inVtabMethod = 0;
  }
#endif
  sqlite3_free(pCx->pData);
  sqlite3_free(pCx->aType);
  sqlite3_free(pCx);
}

/*
** Close all cursors
*/
static void closeAllCursors(Vdbe *p){
  int i;
................................................................................
  closeAllCursors(p);
  releaseMemArray(p->aMem, p->nMem);
  sqlite3VdbeFifoClear(&p->sFifo);
  if( p->contextStack ){
    for(i=0; i<p->contextStackTop; i++){
      sqlite3VdbeFifoClear(&p->contextStack[i].sFifo);
    }
    sqlite3_free(p->contextStack);
  }
  p->contextStack = 0;
  p->contextStackDepth = 0;
  p->contextStackTop = 0;
  sqlite3_free(p->zErrMsg);
  p->zErrMsg = 0;
  p->resOnStack = 0;
}

/*
** Set the number of result columns that will be returned by this SQL
** statement. This is now set at compile time, rather than during
................................................................................
** execution of the vdbe program so that sqlite3_column_count() can
** be called on an SQL statement before sqlite3_step().
*/
void sqlite3VdbeSetNumCols(Vdbe *p, int nResColumn){
  Mem *pColName;
  int n;
  releaseMemArray(p->aColName, p->nResColumn*COLNAME_N);
  sqlite3_free(p->aColName);
  n = nResColumn*COLNAME_N;
  p->nResColumn = nResColumn;
  p->aColName = pColName = (Mem*)sqlite3DbMallocZero(db, sizeof(Mem)*n );
  if( p->aColName==0 ) return;
  while( n-- > 0 ){
    (pColName++)->flags = MEM_Null;
  }
}

/*
................................................................................
** Set the name of the idx'th column to be returned by the SQL statement.
** zName must be a pointer to a nul terminated string.
**
** This call must be made after a call to sqlite3VdbeSetNumCols().
**
** If N==P3_STATIC  it means that zName is a pointer to a constant static
** string and we can just copy the pointer. If it is P3_DYNAMIC, then 
** the string is freed using sqlite3_free() when the vdbe is finished with
** it. Otherwise, N bytes of zName are copied.
*/
int sqlite3VdbeSetColName(Vdbe *p, int idx, int var, const char *zName, int N){
  int rc;
  Mem *pColName;
  assert( idx<p->nResColumn );
  assert( var<COLNAME_N );
  if( p->db->mallocFailed ) return SQLITE_NOMEM;
  assert( p->aColName!=0 );
  pColName = &(p->aColName[idx+var*p->nResColumn]);
  if( N==P3_DYNAMIC || N==P3_STATIC ){
    rc = sqlite3VdbeMemSetStr(pColName, zName, -1, SQLITE_UTF8, SQLITE_STATIC);
  }else{
    rc = sqlite3VdbeMemSetStr(pColName, zName, N, SQLITE_UTF8,SQLITE_TRANSIENT);
  }
................................................................................
    char const *zMainFile = sqlite3BtreeGetFilename(db->aDb[0].pBt);
    sqlite3_file *master = 0;
    i64 offset = 0;

    /* Select a master journal file name */
    do {
      u32 random;
      sqlite3_free(zMaster);
      sqlite3Randomness(sizeof(random), &random);
      zMaster = sqlite3MPrintf("%s-mj%08X", zMainFile, random&0x7fffffff);
      if( !zMaster ){
        return SQLITE_NOMEM;
      }
    }while( sqlite3OsFileExists(zMaster) );

    /* Open the master journal. */
    rc = sqlite3OsOpenExclusive(zMaster, &master, 0);
    if( rc!=SQLITE_OK ){
      sqlite3_free(zMaster);
      return rc;
    }
 
    /* Write the name of each database file in the transaction into the new
    ** master journal file. If an error occurs at this point close
    ** and delete the master journal file. All the individual journal files
    ** still have 'null' as the master journal pointer, so they will roll
................................................................................
          needSync = 1;
        }
        rc = sqlite3OsWrite(master, zFile, strlen(zFile)+1, offset);
        offset += strlen(zFile)+1;
        if( rc!=SQLITE_OK ){
          sqlite3OsClose(&master);
          sqlite3OsDelete(zMaster);
          sqlite3_free(zMaster);
          return rc;
        }
      }
    }


    /* Sync the master journal file. Before doing this, open the directory
................................................................................
    zMainFile = sqlite3BtreeGetDirname(db->aDb[0].pBt);
#if 0
    rc = sqlite3OsOpenDirectory(master, zMainFile);
    if( rc!=SQLITE_OK ||
          (needSync && (rc=sqlite3OsSync(master,0))!=SQLITE_OK) ){
      sqlite3OsClose(&master);
      sqlite3OsDelete(zMaster);
      sqlite3_free(zMaster);
      return rc;
    }
#endif

    /* Sync all the db files involved in the transaction. The same call
    ** sets the master journal pointer in each individual journal. If
    ** an error occurs here, do not delete the master journal file.
................................................................................
      Btree *pBt = db->aDb[i].pBt;
      if( pBt && sqlite3BtreeIsInTrans(pBt) ){
        rc = sqlite3BtreeCommitPhaseOne(pBt, zMaster);
      }
    }
    sqlite3OsClose(&master);
    if( rc!=SQLITE_OK ){
      sqlite3_free(zMaster);
      return rc;
    }

    /* Delete the master journal file. This commits the transaction. After
    ** doing this the directory is synced again before any individual
    ** transaction files are deleted.
    */
    rc = sqlite3OsDelete(zMaster);
    sqlite3_free(zMaster);
    zMaster = 0;
    if( rc ){
      return rc;
    }
    rc = sqlite3OsSyncDirectory(zMainFile);
    if( rc!=SQLITE_OK ){
      /* This is not good. The master journal file has been deleted, but
................................................................................
  **
  ** Other errors:
  **
  ** No error:
  **
  */

  if( p->db->mallocFailed ){
    p->rc = SQLITE_NOMEM;
  }
  if( p->magic!=VDBE_MAGIC_RUN ){
    /* Already halted.  Nothing to do. */
    assert( p->magic==VDBE_MAGIC_HALT );
#ifndef SQLITE_OMIT_VIRTUALTABLE
    closeAllCursors(p);
................................................................................
    p->pNext->pPrev = p->pPrev;
  }
  if( p->aOp ){
    for(i=0; i<p->nOp; i++){
      Op *pOp = &p->aOp[i];
      freeP3(pOp->p3type, pOp->p3);
    }
    sqlite3_free(p->aOp);
  }
  releaseMemArray(p->aVar, p->nVar);
  sqlite3_free(p->aLabel);
  sqlite3_free(p->aStack);
  releaseMemArray(p->aColName, p->nResColumn*COLNAME_N);
  sqlite3_free(p->aColName);
  sqlite3_free(p->zSql);
  p->magic = VDBE_MAGIC_DEAD;
  sqlite3_free(p);
}

/*
** If a MoveTo operation is pending on the given cursor, then do that
** MoveTo now.  Return an error code.  If no MoveTo is pending, this
** routine does nothing and returns SQLITE_OK.
*/

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
**
** This file contains code used to implement incremental BLOB I/O.
**
** $Id: vdbeblob.c,v 1.11 2007/06/27 00:36:14 drh Exp $
*/

#include "sqliteInt.h"
#include "vdbeInt.h"

#ifndef SQLITE_OMIT_INCRBLOB

................................................................................
    }

    pTab = sqlite3LocateTable(&sParse, zTable, zDb);
    if( !pTab ){
      if( sParse.zErrMsg ){
        sqlite3_snprintf(sizeof(zErr), zErr, "%s", sParse.zErrMsg);
      }
      sqliteFree(sParse.zErrMsg);
      rc = SQLITE_ERROR;
      sqlite3SafetyOff(db);
      goto blob_open_out;
    }

    /* Now search pTab for the exact column. */
    for(iCol=0; iCol < pTab->nCol; iCol++) {
................................................................................
      ** think that the table has one more column than it really
      ** does. An OP_Column to retrieve this imaginary column will
      ** always return an SQL NULL. This is useful because it means
      ** we can invoke OP_Column to fill in the vdbe cursors type 
      ** and offset cache without causing any IO.
      */
      sqlite3VdbeChangeP2(v, 5, pTab->nCol+1);
      if( !sqlite3MallocFailed() ){
        sqlite3VdbeMakeReady(v, 1, 0, 1, 0);
      }
    }

    rc = sqlite3SafetyOff(db);
    if( rc!=SQLITE_OK || sqlite3MallocFailed() ){
      goto blob_open_out;
    }

    sqlite3_bind_int64((sqlite3_stmt *)v, 1, iRow);
    rc = sqlite3_step((sqlite3_stmt *)v);
    if( rc!=SQLITE_ROW ){
      nAttempt++;
................................................................................
    if( type<12 ){
      sqlite3_snprintf(sizeof(zErr), zErr, "cannot open value of type %s",
          type==0?"null": type==7?"real": "integer"
      );
      rc = SQLITE_ERROR;
      goto blob_open_out;
    }
    pBlob = (Incrblob *)sqliteMalloc(sizeof(Incrblob));
    if( sqlite3MallocFailed() ){
      sqliteFree(pBlob);
      goto blob_open_out;
    }
    pBlob->flags = flags;
    pBlob->pCsr =  v->apCsr[0]->pCursor;
    sqlite3BtreeCacheOverflow(pBlob->pCsr);
    pBlob->pStmt = (sqlite3_stmt *)v;
    pBlob->iOffset = v->apCsr[0]->aOffset[iCol];
................................................................................
  }else if( rc==SQLITE_OK ){
    sqlite3_snprintf(sizeof(zErr), zErr, "no such rowid: %lld", iRow);
    rc = SQLITE_ERROR;
  }

blob_open_out:
  zErr[sizeof(zErr)-1] = '\0';
  if( rc!=SQLITE_OK || sqlite3MallocFailed() ){
    sqlite3_finalize((sqlite3_stmt *)v);
  }
  sqlite3Error(db, rc, (rc==SQLITE_OK?0:zErr));
  return sqlite3ApiExit(db, rc);
}

/*
** Close a blob handle that was previously created using
** sqlite3_blob_open().
*/
int sqlite3_blob_close(sqlite3_blob *pBlob){
  Incrblob *p = (Incrblob *)pBlob;
  sqlite3_stmt *pStmt = p->pStmt;
  sqliteFree(p);
  return sqlite3_finalize(pStmt);
}


static int blobReadWrite(
  sqlite3_blob *pBlob, 
  void *z, 

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
**
** This file contains code used to implement incremental BLOB I/O.
**
** $Id: vdbeblob.c,v 1.12 2007/08/16 04:30:41 drh Exp $
*/

#include "sqliteInt.h"
#include "vdbeInt.h"

#ifndef SQLITE_OMIT_INCRBLOB

................................................................................
    }

    pTab = sqlite3LocateTable(&sParse, zTable, zDb);
    if( !pTab ){
      if( sParse.zErrMsg ){
        sqlite3_snprintf(sizeof(zErr), zErr, "%s", sParse.zErrMsg);
      }
      sqlite3_free(sParse.zErrMsg);
      rc = SQLITE_ERROR;
      sqlite3SafetyOff(db);
      goto blob_open_out;
    }

    /* Now search pTab for the exact column. */
    for(iCol=0; iCol < pTab->nCol; iCol++) {
................................................................................
      ** think that the table has one more column than it really
      ** does. An OP_Column to retrieve this imaginary column will
      ** always return an SQL NULL. This is useful because it means
      ** we can invoke OP_Column to fill in the vdbe cursors type 
      ** and offset cache without causing any IO.
      */
      sqlite3VdbeChangeP2(v, 5, pTab->nCol+1);
      if( !db->mallocFailed ){
        sqlite3VdbeMakeReady(v, 1, 0, 1, 0);
      }
    }

    rc = sqlite3SafetyOff(db);
    if( rc!=SQLITE_OK || db->mallocFailed ){
      goto blob_open_out;
    }

    sqlite3_bind_int64((sqlite3_stmt *)v, 1, iRow);
    rc = sqlite3_step((sqlite3_stmt *)v);
    if( rc!=SQLITE_ROW ){
      nAttempt++;
................................................................................
    if( type<12 ){
      sqlite3_snprintf(sizeof(zErr), zErr, "cannot open value of type %s",
          type==0?"null": type==7?"real": "integer"
      );
      rc = SQLITE_ERROR;
      goto blob_open_out;
    }
    pBlob = (Incrblob *)sqlite3DbMallocZero(db, sizeof(Incrblob));
    if( db->mallocFailed ){
      sqlite3_free(pBlob);
      goto blob_open_out;
    }
    pBlob->flags = flags;
    pBlob->pCsr =  v->apCsr[0]->pCursor;
    sqlite3BtreeCacheOverflow(pBlob->pCsr);
    pBlob->pStmt = (sqlite3_stmt *)v;
    pBlob->iOffset = v->apCsr[0]->aOffset[iCol];
................................................................................
  }else if( rc==SQLITE_OK ){
    sqlite3_snprintf(sizeof(zErr), zErr, "no such rowid: %lld", iRow);
    rc = SQLITE_ERROR;
  }

blob_open_out:
  zErr[sizeof(zErr)-1] = '\0';
  if( rc!=SQLITE_OK || db->mallocFailed ){
    sqlite3_finalize((sqlite3_stmt *)v);
  }
  sqlite3Error(db, rc, (rc==SQLITE_OK?0:zErr));
  return sqlite3ApiExit(db, rc);
}

/*
** Close a blob handle that was previously created using
** sqlite3_blob_open().
*/
int sqlite3_blob_close(sqlite3_blob *pBlob){
  Incrblob *p = (Incrblob *)pBlob;
  sqlite3_stmt *pStmt = p->pStmt;
  sqlite3_free(p);
  return sqlite3_finalize(pStmt);
}


static int blobReadWrite(
  sqlite3_blob *pBlob, 
  void *z, 

** we run out of memory.  Leave space on the page for nEntry entries.
*/
static FifoPage *allocateFifoPage(int nEntry){
  FifoPage *pPage;
  if( nEntry>32767 ){
    nEntry = 32767;
  }
  pPage = sqliteMallocRaw( sizeof(FifoPage) + sizeof(i64)*(nEntry-1) );
  if( pPage ){
    pPage->nSlot = nEntry;
    pPage->iWrite = 0;
    pPage->iRead = 0;
    pPage->pNext = 0;
  }
  return pPage;
................................................................................
  assert( pPage->iWrite<=pPage->nSlot );
  assert( pPage->iRead<pPage->nSlot );
  assert( pPage->iRead>=0 );
  *pVal = pPage->aSlot[pPage->iRead++];
  pFifo->nEntry--;
  if( pPage->iRead>=pPage->iWrite ){
    pFifo->pFirst = pPage->pNext;
    sqliteFree(pPage);
    if( pFifo->nEntry==0 ){
      assert( pFifo->pLast==pPage );
      pFifo->pLast = 0;
    }else{
      assert( pFifo->pFirst!=0 );
    }
  }else{
................................................................................
** Delete all information from a Fifo object.   Free all memory held
** by the Fifo.
*/
void sqlite3VdbeFifoClear(Fifo *pFifo){
  FifoPage *pPage, *pNextPage;
  for(pPage=pFifo->pFirst; pPage; pPage=pNextPage){
    pNextPage = pPage->pNext;
    sqliteFree(pPage);
  }
  sqlite3VdbeFifoInit(pFifo);
}

** we run out of memory.  Leave space on the page for nEntry entries.
*/
static FifoPage *allocateFifoPage(int nEntry){
  FifoPage *pPage;
  if( nEntry>32767 ){
    nEntry = 32767;
  }
  pPage = sqlite3_malloc( sizeof(FifoPage) + sizeof(i64)*(nEntry-1) );
  if( pPage ){
    pPage->nSlot = nEntry;
    pPage->iWrite = 0;
    pPage->iRead = 0;
    pPage->pNext = 0;
  }
  return pPage;
................................................................................
  assert( pPage->iWrite<=pPage->nSlot );
  assert( pPage->iRead<pPage->nSlot );
  assert( pPage->iRead>=0 );
  *pVal = pPage->aSlot[pPage->iRead++];
  pFifo->nEntry--;
  if( pPage->iRead>=pPage->iWrite ){
    pFifo->pFirst = pPage->pNext;
    sqlite3_free(pPage);
    if( pFifo->nEntry==0 ){
      assert( pFifo->pLast==pPage );
      pFifo->pLast = 0;
    }else{
      assert( pFifo->pFirst!=0 );
    }
  }else{
................................................................................
** Delete all information from a Fifo object.   Free all memory held
** by the Fifo.
*/
void sqlite3VdbeFifoClear(Fifo *pFifo){
  FifoPage *pPage, *pNextPage;
  for(pPage=pFifo->pFirst; pPage; pPage=pNextPage){
    pNextPage = pPage->pNext;
    sqlite3_free(pPage);
  }
  sqlite3VdbeFifoInit(pFifo);
}

#include <ctype.h>
#include "vdbeInt.h"

/*
** Call sqlite3VdbeMemExpandBlob() on the supplied value (type Mem*)
** P if required.
*/
#define expandBlob(P) (((P)->flags&MEM_Zero)?sqlite3VdbeMemExpandBlob(P):0)

/*
** If pMem is an object with a valid string representation, this routine
** ensures the internal encoding for the string representation is
** 'desiredEnc', one of SQLITE_UTF8, SQLITE_UTF16LE or SQLITE_UTF16BE.
**
** If pMem is not a string object, or the encoding of the string
................................................................................
}

/*
** Make the given Mem object MEM_Dyn.
**
** Return SQLITE_OK on success or SQLITE_NOMEM if malloc fails.
*/
int sqlite3VdbeMemDynamicify(Mem *pMem){
  int n;
  u8 *z;
  expandBlob(pMem);
  if( (pMem->flags & (MEM_Ephem|MEM_Static|MEM_Short))==0 ){
    return SQLITE_OK;
  }
  assert( (pMem->flags & MEM_Dyn)==0 );
  n = pMem->n;
  assert( pMem->flags & (MEM_Str|MEM_Blob) );
  z = sqliteMallocRaw( n+2 );
  if( z==0 ){
    return SQLITE_NOMEM;
  }
  pMem->flags |= MEM_Dyn|MEM_Term;
  pMem->xDel = 0;
  memcpy(z, pMem->z, n );
  z[n] = 0;
................................................................................
}

/*
** If the given Mem* has a zero-filled tail, turn it into an ordinary
** blob stored in dynamically allocated space.
*/
#ifndef SQLITE_OMIT_INCRBLOB
int sqlite3VdbeMemExpandBlob(Mem *pMem){
  if( pMem->flags & MEM_Zero ){
    char *pNew;
    int nByte;
    assert( (pMem->flags & MEM_Blob)!=0 );
    nByte = pMem->n + pMem->u.i;
    if( nByte<=0 ) nByte = 1;
    pNew = sqliteMalloc(nByte);
    if( pNew==0 ){ 

      return SQLITE_NOMEM;
    }
    memcpy(pNew, pMem->z, pMem->n);
    memset(&pNew[pMem->n], 0, pMem->u.i);
    sqlite3VdbeMemRelease(pMem);
    pMem->z = pNew;
    pMem->n += pMem->u.i;
................................................................................

/*
** Make the given Mem object either MEM_Short or MEM_Dyn so that bytes
** of the Mem.z[] array can be modified.
**
** Return SQLITE_OK on success or SQLITE_NOMEM if malloc fails.
*/
int sqlite3VdbeMemMakeWriteable(Mem *pMem){
  int n;
  u8 *z;
  expandBlob(pMem);
  if( (pMem->flags & (MEM_Ephem|MEM_Static))==0 ){
    return SQLITE_OK;
  }
  assert( (pMem->flags & MEM_Dyn)==0 );
  assert( pMem->flags & (MEM_Str|MEM_Blob) );
  if( (n = pMem->n)+2<sizeof(pMem->zShort) ){
    z = (u8*)pMem->zShort;
    pMem->flags |= MEM_Short|MEM_Term;
  }else{
    z = sqliteMallocRaw( n+2 );
    if( z==0 ){

      return SQLITE_NOMEM;
    }
    pMem->flags |= MEM_Dyn|MEM_Term;
    pMem->xDel = 0;
  }
  memcpy(z, pMem->z, n );
  z[n] = 0;
................................................................................
  assert(0==(1&(int)pMem->z));
  return SQLITE_OK;
}

/*
** Make sure the given Mem is \u0000 terminated.
*/
int sqlite3VdbeMemNulTerminate(Mem *pMem){
  if( (pMem->flags & MEM_Term)!=0 || (pMem->flags & MEM_Str)==0 ){
    return SQLITE_OK;   /* Nothing to do */
  }
  if( pMem->flags & (MEM_Static|MEM_Ephem) ){
    return sqlite3VdbeMemMakeWriteable(pMem);
  }else{
    char *z; 
    sqlite3VdbeMemExpandBlob(pMem);
    z = sqliteMalloc(pMem->n+2);




    if( !z ) return SQLITE_NOMEM;
    memcpy(z, pMem->z, pMem->n);
    z[pMem->n] = 0;
    z[pMem->n+1] = 0;
    if( pMem->xDel ){
      pMem->xDel(pMem->z);
    }else{
      sqliteFree(pMem->z);
    }
    pMem->xDel = 0;
    pMem->z = z;
    pMem->flags |= MEM_Term;
  }
  return SQLITE_OK;
}
................................................................................
    ctx.s.flags = MEM_Null;
    ctx.s.z = pMem->zShort;
    ctx.pMem = pMem;
    ctx.pFunc = pFunc;
    ctx.isError = 0;
    pFunc->xFinalize(&ctx);
    if( pMem->z && pMem->z!=pMem->zShort ){
      sqliteFree( pMem->z );
    }
    *pMem = ctx.s;
    if( pMem->flags & MEM_Short ){
      pMem->z = pMem->zShort;
    }
    if( ctx.isError ){
      rc = SQLITE_ERROR;
................................................................................
        sqlite3VdbeMemFinalize(p, p->u.pDef);
        assert( (p->flags & MEM_Agg)==0 );
        sqlite3VdbeMemRelease(p);
      }else{
        p->xDel((void *)p->z);
      }
    }else{
      sqliteFree(p->z);
    }
    p->z = 0;
    p->xDel = 0;
  }
}

/*
................................................................................
** The pMem structure is assumed to be uninitialized.  Any prior content
** is overwritten without being freed.
**
** If this routine fails for any reason (malloc returns NULL or unable
** to read from the disk) then the pMem is left in an inconsistent state.
*/
int sqlite3VdbeMemFromBtree(

  BtCursor *pCur,   /* Cursor pointing at record to retrieve. */
  int offset,       /* Offset from the start of data to return bytes from. */
  int amt,          /* Number of bytes to return. */
  int key,          /* If true, retrieve from the btree key, not data. */
  Mem *pMem         /* OUT: Return data in this Mem structure. */
){
  char *zData;       /* Data from the btree layer */
................................................................................
  pMem->n = amt;
  if( offset+amt<=available ){
    pMem->z = &zData[offset];
    pMem->flags = MEM_Blob|MEM_Ephem;
  }else{
    int rc;
    if( amt>NBFS-2 ){
      zData = (char *)sqliteMallocRaw(amt+2);
      if( !zData ){

        return SQLITE_NOMEM;
      }
      pMem->flags = MEM_Blob|MEM_Dyn|MEM_Term;
      pMem->xDel = 0;
    }else{
      zData = &(pMem->zShort[0]);
      pMem->flags = MEM_Blob|MEM_Short|MEM_Term;
................................................................................
    }
    zData[amt] = 0;
    zData[amt+1] = 0;
    if( rc!=SQLITE_OK ){
      if( amt>NBFS-2 ){
        assert( zData!=pMem->zShort );
        assert( pMem->flags & MEM_Dyn );
        sqliteFree(zData);
      } else {
        assert( zData==pMem->zShort );
        assert( pMem->flags & MEM_Short );
      }
      return rc;
    }
  }
................................................................................
** parameter, which must be one of SQLITE_UTF16BE, SQLITE_UTF16LE or
** SQLITE_UTF8.
**
** (2006-02-16:)  The enc value can be or-ed with SQLITE_UTF16_ALIGNED.
** If that is the case, then the result must be aligned on an even byte
** boundary.
*/
const void *sqlite3ValueText(sqlite3_value* pVal, u8 enc){
  if( !pVal ) return 0;
  assert( (enc&3)==(enc&~SQLITE_UTF16_ALIGNED) );

  if( pVal->flags&MEM_Null ){
    return 0;
  }
  assert( (MEM_Blob>>3) == MEM_Str );
  pVal->flags |= (pVal->flags & MEM_Blob)>>3;
  expandBlob(pVal);
  if( pVal->flags&MEM_Str ){
    sqlite3VdbeChangeEncoding(pVal, enc & ~SQLITE_UTF16_ALIGNED);
    if( (enc & SQLITE_UTF16_ALIGNED)!=0 && 1==(1&(int)pVal->z) ){
      assert( (pVal->flags & (MEM_Ephem|MEM_Static))!=0 );
      if( sqlite3VdbeMemMakeWriteable(pVal)!=SQLITE_OK ){
        return 0;
      }
    }
    sqlite3VdbeMemNulTerminate(pVal);
  }else{
    assert( (pVal->flags&MEM_Blob)==0 );
    sqlite3VdbeMemStringify(pVal, enc);
    assert( 0==(1&(int)pVal->z) );
  }
  assert(pVal->enc==(enc & ~SQLITE_UTF16_ALIGNED) || sqlite3MallocFailed() );
  if( pVal->enc==(enc & ~SQLITE_UTF16_ALIGNED) ){
    return pVal->z;
  }else{
    return 0;
  }
}

/*
** Create a new sqlite3_value object.
*/
sqlite3_value *sqlite3ValueNew(void){
  Mem *p = sqliteMalloc(sizeof(*p));
  if( p ){
    p->flags = MEM_Null;
    p->type = SQLITE_NULL;


  }
  return p;
}

/*
** Create a new sqlite3_value object, containing the value of pExpr.
**
................................................................................
** token (i.e. "5", "5.1", "NULL", "'a string'"). If the expression can
** be converted directly into a value, then the value is allocated and
** a pointer written to *ppVal. The caller is responsible for deallocating
** the value by passing it to sqlite3ValueFree() later on. If the expression
** cannot be converted to a value, then *ppVal is set to NULL.
*/
int sqlite3ValueFromExpr(
  Expr *pExpr, 
  u8 enc, 

  u8 affinity,
  sqlite3_value **ppVal
){
  int op;
  char *zVal = 0;
  sqlite3_value *pVal = 0;

  if( !pExpr ){
    *ppVal = 0;
    return SQLITE_OK;
  }
  op = pExpr->op;

  if( op==TK_STRING || op==TK_FLOAT || op==TK_INTEGER ){
    zVal = sqliteStrNDup((char*)pExpr->token.z, pExpr->token.n);
    pVal = sqlite3ValueNew();
    if( !zVal || !pVal ) goto no_mem;
    sqlite3Dequote(zVal);
    sqlite3ValueSetStr(pVal, -1, zVal, SQLITE_UTF8, sqlite3FreeX);
    if( (op==TK_INTEGER || op==TK_FLOAT ) && affinity==SQLITE_AFF_NONE ){
      sqlite3ValueApplyAffinity(pVal, SQLITE_AFF_NUMERIC, enc);
    }else{
      sqlite3ValueApplyAffinity(pVal, affinity, enc);
    }
  }else if( op==TK_UMINUS ) {
    if( SQLITE_OK==sqlite3ValueFromExpr(pExpr->pLeft, enc, affinity, &pVal) ){
................................................................................
      pVal->r = -1.0 * pVal->r;
    }
  }
#ifndef SQLITE_OMIT_BLOB_LITERAL
  else if( op==TK_BLOB ){
    int nVal;
    pVal = sqlite3ValueNew();
    zVal = sqliteStrNDup((char*)pExpr->token.z+1, pExpr->token.n-1);
    if( !zVal || !pVal ) goto no_mem;
    sqlite3Dequote(zVal);
    nVal = strlen(zVal)/2;
    sqlite3VdbeMemSetStr(pVal, sqlite3HexToBlob(zVal), nVal, 0, sqlite3FreeX);
    sqliteFree(zVal);
  }
#endif

  *ppVal = pVal;
  return SQLITE_OK;

no_mem:

  sqliteFree(zVal);
  sqlite3ValueFree(pVal);
  *ppVal = 0;
  return SQLITE_NOMEM;
}

/*
** Change the string value of an sqlite3_value object
*/
void sqlite3ValueSetStr(

  sqlite3_value *v, 
  int n, 

  const void *z, 
  u8 enc,

  void (*xDel)(void*)
){
  if( v ) sqlite3VdbeMemSetStr((Mem *)v, z, n, enc, xDel);
}

/*
** Free an sqlite3_value object
*/
void sqlite3ValueFree(sqlite3_value *v){
  if( !v ) return;
  sqlite3ValueSetStr(v, 0, 0, SQLITE_UTF8, SQLITE_STATIC);
  sqliteFree(v);
}

/*
** Return the number of bytes in the sqlite3_value object assuming
** that it uses the encoding "enc"
*/
int sqlite3ValueBytes(sqlite3_value *pVal, u8 enc){

#include <ctype.h>
#include "vdbeInt.h"

/*
** Call sqlite3VdbeMemExpandBlob() on the supplied value (type Mem*)
** P if required.
*/
#define expandBlob(D,P) (((P)->flags&MEM_Zero)?sqlite3VdbeMemExpandBlob(D,P):0)

/*
** If pMem is an object with a valid string representation, this routine
** ensures the internal encoding for the string representation is
** 'desiredEnc', one of SQLITE_UTF8, SQLITE_UTF16LE or SQLITE_UTF16BE.
**
** If pMem is not a string object, or the encoding of the string
................................................................................
}

/*
** Make the given Mem object MEM_Dyn.
**
** Return SQLITE_OK on success or SQLITE_NOMEM if malloc fails.
*/
int sqlite3VdbeMemDynamicify(sqlite3 *db, Mem *pMem){
  int n;
  u8 *z;
  expandBlob(db, pMem);
  if( (pMem->flags & (MEM_Ephem|MEM_Static|MEM_Short))==0 ){
    return SQLITE_OK;
  }
  assert( (pMem->flags & MEM_Dyn)==0 );
  n = pMem->n;
  assert( pMem->flags & (MEM_Str|MEM_Blob) );
  z = sqlite3_malloc( n+2 );
  if( z==0 ){
    return SQLITE_NOMEM;
  }
  pMem->flags |= MEM_Dyn|MEM_Term;
  pMem->xDel = 0;
  memcpy(z, pMem->z, n );
  z[n] = 0;
................................................................................
}

/*
** If the given Mem* has a zero-filled tail, turn it into an ordinary
** blob stored in dynamically allocated space.
*/
#ifndef SQLITE_OMIT_INCRBLOB
int sqlite3VdbeMemExpandBlob(sqlite3 *db, Mem *pMem){
  if( pMem->flags & MEM_Zero ){
    char *pNew;
    int nByte;
    assert( (pMem->flags & MEM_Blob)!=0 );
    nByte = pMem->n + pMem->u.i;
    if( nByte<=0 ) nByte = 1;
    pNew = sqlite3_malloc(nByte);
    if( pNew==0 ){
      if( db ) db->mallocFailed = 1;
      return SQLITE_NOMEM;
    }
    memcpy(pNew, pMem->z, pMem->n);
    memset(&pNew[pMem->n], 0, pMem->u.i);
    sqlite3VdbeMemRelease(pMem);
    pMem->z = pNew;
    pMem->n += pMem->u.i;
................................................................................

/*
** Make the given Mem object either MEM_Short or MEM_Dyn so that bytes
** of the Mem.z[] array can be modified.
**
** Return SQLITE_OK on success or SQLITE_NOMEM if malloc fails.
*/
int sqlite3VdbeMemMakeWriteable(sqlite3 *db, Mem *pMem){
  int n;
  u8 *z;
  expandBlob(db, pMem);
  if( (pMem->flags & (MEM_Ephem|MEM_Static))==0 ){
    return SQLITE_OK;
  }
  assert( (pMem->flags & MEM_Dyn)==0 );
  assert( pMem->flags & (MEM_Str|MEM_Blob) );
  if( (n = pMem->n)+2<sizeof(pMem->zShort) ){
    z = (u8*)pMem->zShort;
    pMem->flags |= MEM_Short|MEM_Term;
  }else{
    z = sqlite3_malloc( n+2 );
    if( z==0 ){
      db->mallocFailed = 1;
      return SQLITE_NOMEM;
    }
    pMem->flags |= MEM_Dyn|MEM_Term;
    pMem->xDel = 0;
  }
  memcpy(z, pMem->z, n );
  z[n] = 0;
................................................................................
  assert(0==(1&(int)pMem->z));
  return SQLITE_OK;
}

/*
** Make sure the given Mem is \u0000 terminated.
*/
int sqlite3VdbeMemNulTerminate(sqlite3 *db, Mem *pMem){
  if( (pMem->flags & MEM_Term)!=0 || (pMem->flags & MEM_Str)==0 ){
    return SQLITE_OK;   /* Nothing to do */
  }
  if( pMem->flags & (MEM_Static|MEM_Ephem) ){
    return sqlite3VdbeMemMakeWriteable(pMem);
  }else{
    char *z; 
    sqlite3VdbeMemExpandBlob(db, pMem);
    z = sqlite3_malloc(pMem->n+2);
    if( !z ){
       db->mallocFailed = 1;
       return SQLITE_NOMEM;
    }

    memcpy(z, pMem->z, pMem->n);
    z[pMem->n] = 0;
    z[pMem->n+1] = 0;
    if( pMem->xDel ){
      pMem->xDel(pMem->z);
    }else{
      sqlite3_free(pMem->z);
    }
    pMem->xDel = 0;
    pMem->z = z;
    pMem->flags |= MEM_Term;
  }
  return SQLITE_OK;
}
................................................................................
    ctx.s.flags = MEM_Null;
    ctx.s.z = pMem->zShort;
    ctx.pMem = pMem;
    ctx.pFunc = pFunc;
    ctx.isError = 0;
    pFunc->xFinalize(&ctx);
    if( pMem->z && pMem->z!=pMem->zShort ){
      sqlite3_free( pMem->z );
    }
    *pMem = ctx.s;
    if( pMem->flags & MEM_Short ){
      pMem->z = pMem->zShort;
    }
    if( ctx.isError ){
      rc = SQLITE_ERROR;
................................................................................
        sqlite3VdbeMemFinalize(p, p->u.pDef);
        assert( (p->flags & MEM_Agg)==0 );
        sqlite3VdbeMemRelease(p);
      }else{
        p->xDel((void *)p->z);
      }
    }else{
      sqlite3_free(p->z);
    }
    p->z = 0;
    p->xDel = 0;
  }
}

/*
................................................................................
** The pMem structure is assumed to be uninitialized.  Any prior content
** is overwritten without being freed.
**
** If this routine fails for any reason (malloc returns NULL or unable
** to read from the disk) then the pMem is left in an inconsistent state.
*/
int sqlite3VdbeMemFromBtree(
  sqlite3 *db,      /* Database connect to report malloc errors to */
  BtCursor *pCur,   /* Cursor pointing at record to retrieve. */
  int offset,       /* Offset from the start of data to return bytes from. */
  int amt,          /* Number of bytes to return. */
  int key,          /* If true, retrieve from the btree key, not data. */
  Mem *pMem         /* OUT: Return data in this Mem structure. */
){
  char *zData;       /* Data from the btree layer */
................................................................................
  pMem->n = amt;
  if( offset+amt<=available ){
    pMem->z = &zData[offset];
    pMem->flags = MEM_Blob|MEM_Ephem;
  }else{
    int rc;
    if( amt>NBFS-2 ){
      zData = (char *)sqlite3_malloc(amt+2);
      if( !zData ){
        db->mallocFailed = 1;
        return SQLITE_NOMEM;
      }
      pMem->flags = MEM_Blob|MEM_Dyn|MEM_Term;
      pMem->xDel = 0;
    }else{
      zData = &(pMem->zShort[0]);
      pMem->flags = MEM_Blob|MEM_Short|MEM_Term;
................................................................................
    }
    zData[amt] = 0;
    zData[amt+1] = 0;
    if( rc!=SQLITE_OK ){
      if( amt>NBFS-2 ){
        assert( zData!=pMem->zShort );
        assert( pMem->flags & MEM_Dyn );
        sqlite3_free(zData);
      } else {
        assert( zData==pMem->zShort );
        assert( pMem->flags & MEM_Short );
      }
      return rc;
    }
  }
................................................................................
** parameter, which must be one of SQLITE_UTF16BE, SQLITE_UTF16LE or
** SQLITE_UTF8.
**
** (2006-02-16:)  The enc value can be or-ed with SQLITE_UTF16_ALIGNED.
** If that is the case, then the result must be aligned on an even byte
** boundary.
*/
const void *sqlite3ValueText(sqlite3 *db, sqlite3_value* pVal, u8 enc){
  if( !pVal ) return 0;
  assert( (enc&3)==(enc&~SQLITE_UTF16_ALIGNED) );

  if( pVal->flags&MEM_Null ){
    return 0;
  }
  assert( (MEM_Blob>>3) == MEM_Str );
  pVal->flags |= (pVal->flags & MEM_Blob)>>3;
  expandBlob(db, pVal);
  if( pVal->flags&MEM_Str ){
    sqlite3VdbeChangeEncoding(pVal, enc & ~SQLITE_UTF16_ALIGNED);
    if( (enc & SQLITE_UTF16_ALIGNED)!=0 && 1==(1&(int)pVal->z) ){
      assert( (pVal->flags & (MEM_Ephem|MEM_Static))!=0 );
      if( sqlite3VdbeMemMakeWriteable(db, pVal)!=SQLITE_OK ){
        return 0;
      }
    }
    sqlite3VdbeMemNulTerminate(db, pVal);
  }else{
    assert( (pVal->flags&MEM_Blob)==0 );
    sqlite3VdbeMemStringify(db, pVal, enc);
    assert( 0==(1&(int)pVal->z) );
  }
  assert(pVal->enc==(enc & ~SQLITE_UTF16_ALIGNED) || db->mallocFailed );
  if( pVal->enc==(enc & ~SQLITE_UTF16_ALIGNED) ){
    return pVal->z;
  }else{
    return 0;
  }
}

/*
** Create a new sqlite3_value object.
*/
sqlite3_value *sqlite3ValueNew(sqlite3 *db){
  Mem *p = sqlite3_malloc(sizeof(*p));
  if( p ){
    p->flags = MEM_Null;
    p->type = SQLITE_NULL;
  }else{
    db->mallocFailed = 1;
  }
  return p;
}

/*
** Create a new sqlite3_value object, containing the value of pExpr.
**
................................................................................
** token (i.e. "5", "5.1", "NULL", "'a string'"). If the expression can
** be converted directly into a value, then the value is allocated and
** a pointer written to *ppVal. The caller is responsible for deallocating
** the value by passing it to sqlite3ValueFree() later on. If the expression
** cannot be converted to a value, then *ppVal is set to NULL.
*/
int sqlite3ValueFromExpr(
  sqlite3 *db,              /* Report malloc() errors here */
  Expr *pExpr,              /* The expression to evaluate */
  u8 enc,                   /* Encoding to use */
  u8 affinity,              /* Affinity to use */
  sqlite3_value **ppVal     /* Write the new value here */
){
  int op;
  char *zVal = 0;
  sqlite3_value *pVal = 0;

  if( !pExpr ){
    *ppVal = 0;
    return SQLITE_OK;
  }
  op = pExpr->op;

  if( op==TK_STRING || op==TK_FLOAT || op==TK_INTEGER ){
    zVal = sqlite3StrNDup((char*)pExpr->token.z, pExpr->token.n);
    pVal = sqlite3ValueNew(db);
    if( !zVal || !pVal ) goto no_mem;
    sqlite3Dequote(zVal);
    sqlite3ValueSetStr(db, pVal, -1, zVal, SQLITE_UTF8, sqlite3FreeX);
    if( (op==TK_INTEGER || op==TK_FLOAT ) && affinity==SQLITE_AFF_NONE ){
      sqlite3ValueApplyAffinity(pVal, SQLITE_AFF_NUMERIC, enc);
    }else{
      sqlite3ValueApplyAffinity(pVal, affinity, enc);
    }
  }else if( op==TK_UMINUS ) {
    if( SQLITE_OK==sqlite3ValueFromExpr(pExpr->pLeft, enc, affinity, &pVal) ){
................................................................................
      pVal->r = -1.0 * pVal->r;
    }
  }
#ifndef SQLITE_OMIT_BLOB_LITERAL
  else if( op==TK_BLOB ){
    int nVal;
    pVal = sqlite3ValueNew();
    zVal = sqlite3StrNDup((char*)pExpr->token.z+1, pExpr->token.n-1);
    if( !zVal || !pVal ) goto no_mem;
    sqlite3Dequote(zVal);
    nVal = strlen(zVal)/2;
    sqlite3VdbeMemSetStr(pVal, sqlite3HexToBlob(zVal), nVal, 0, sqlite3FreeX);
    sqlite3_free(zVal);
  }
#endif

  *ppVal = pVal;
  return SQLITE_OK;

no_mem:
  db->mallocFailed = 1;
  sqlite3_free(zVal);
  sqlite3ValueFree(pVal);
  *ppVal = 0;
  return SQLITE_NOMEM;
}

/*
** Change the string value of an sqlite3_value object
*/
void sqlite3ValueSetStr(
  sqlite3 *db,          /* Report malloc errors here */
  sqlite3_value *v,     /* Value to be set */

  int n,                /* Length of string z */
  const void *z,        /* Text of the new string */

  u8 enc,               /* Encoding to use */
  void (*xDel)(void*)   /* Destructor for the string */
){
  if( v ) sqlite3VdbeMemSetStr(db, (Mem *)v, z, n, enc, xDel);
}

/*
** Free an sqlite3_value object
*/
void sqlite3ValueFree(sqlite3_value *v){
  if( !v ) return;
  sqlite3ValueSetStr(v, 0, 0, SQLITE_UTF8, SQLITE_STATIC);
  sqlite3_free(v);
}

/*
** Return the number of bytes in the sqlite3_value object assuming
** that it uses the encoding "enc"
*/
int sqlite3ValueBytes(sqlite3_value *pVal, u8 enc){

**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains code used to help implement virtual tables.
**
** $Id: vtab.c,v 1.48 2007/06/26 10:38:55 danielk1977 Exp $
*/
#ifndef SQLITE_OMIT_VIRTUALTABLE
#include "sqliteInt.h"

static int createModule(
  sqlite3 *db,                    /* Database in which module is registered */
  const char *zName,              /* Name assigned to this module */
  const sqlite3_module *pModule,  /* The definition of the module */
  void *pAux,                     /* Context pointer for xCreate/xConnect */
  void (*xDestroy)(void *)        /* Module destructor function */
) {
  int nName = strlen(zName);
  Module *pMod = (Module *)sqliteMallocRaw(sizeof(Module) + nName + 1);
  if( pMod ){
    char *zCopy = (char *)(&pMod[1]);
    memcpy(zCopy, zName, nName+1);
    pMod->zName = zCopy;
    pMod->pModule = pModule;
    pMod->pAux = pAux;
    pMod->xDestroy = xDestroy;
    pMod = (Module *)sqlite3HashInsert(&db->aModule, zCopy, nName, (void*)pMod);
    if( pMod && pMod->xDestroy ){
      pMod->xDestroy(pMod->pAux);
    }
    sqliteFree(pMod);
    sqlite3ResetInternalSchema(db, 0);
  }
  return sqlite3ApiExit(db, SQLITE_OK);
}


/*
................................................................................
    assert( p->pMod && p->pMod->pModule );
    sqlite3VtabUnlock(p->pSchema->db, pVtab);
    p->pVtab = 0;
  }
  if( p->azModuleArg ){
    int i;
    for(i=0; i<p->nModuleArg; i++){
      sqliteFree(p->azModuleArg[i]);
    }
    sqliteFree(p->azModuleArg);
  }
}

/*
** Add a new module argument to pTable->azModuleArg[].
** The string is not copied - the pointer is stored.  The
** string will be freed automatically when the table is
** deleted.
*/
static void addModuleArgument(Table *pTable, char *zArg){
  int i = pTable->nModuleArg++;
  int nBytes = sizeof(char *)*(1+pTable->nModuleArg);
  char **azModuleArg;
  azModuleArg = sqliteRealloc(pTable->azModuleArg, nBytes);
  if( azModuleArg==0 ){
    int j;
    for(j=0; j<i; j++){
      sqliteFree(pTable->azModuleArg[j]);
    }
    sqliteFree(zArg);
    sqliteFree(pTable->azModuleArg);
    pTable->nModuleArg = 0;

  }else{
    azModuleArg[i] = zArg;
    azModuleArg[i+1] = 0;
  }
  pTable->azModuleArg = azModuleArg;
}

................................................................................
  Parse *pParse,        /* Parsing context */
  Token *pName1,        /* Name of new table, or database name */
  Token *pName2,        /* Name of new table or NULL */
  Token *pModuleName    /* Name of the module for the virtual table */
){
  int iDb;              /* The database the table is being created in */
  Table *pTable;        /* The new virtual table */


#ifndef SQLITE_OMIT_SHARED_CACHE
  if( sqlite3ThreadDataReadOnly()->useSharedData ){
    sqlite3ErrorMsg(pParse, "Cannot use virtual tables in shared-cache mode");
    return;
  }
#endif

  sqlite3StartTable(pParse, pName1, pName2, 0, 0, 1, 0);
  pTable = pParse->pNewTable;
  if( pTable==0 || pParse->nErr ) return;
  assert( 0==pTable->pIndex );


  iDb = sqlite3SchemaToIndex(pParse->db, pTable->pSchema);
  assert( iDb>=0 );

  pTable->isVirtual = 1;
  pTable->nModuleArg = 0;
  addModuleArgument(pTable, sqlite3NameFromToken(pModuleName));
  addModuleArgument(pTable, sqlite3StrDup(pParse->db->aDb[iDb].zName));
  addModuleArgument(pTable, sqlite3StrDup(pTable->zName));
  pParse->sNameToken.n = pModuleName->z + pModuleName->n - pName1->z;

#ifndef SQLITE_OMIT_AUTHORIZATION
  /* Creating a virtual table invokes the authorization callback twice.
  ** The first invocation, to obtain permission to INSERT a row into the
  ** sqlite_master table, has already been made by sqlite3StartTable().
  ** The second call, to obtain permission to create the table, is made now.
................................................................................
** in pParse->zArg[] and appends it to the list of arguments on the
** virtual table currently under construction in pParse->pTable.
*/
static void addArgumentToVtab(Parse *pParse){
  if( pParse->sArg.z && pParse->pNewTable ){
    const char *z = (const char*)pParse->sArg.z;
    int n = pParse->sArg.n;

    addModuleArgument(pParse->pNewTable, sqliteStrNDup(z, n));
  }
}

/*
** The parser calls this routine after the CREATE VIRTUAL TABLE statement
** has been completely parsed.
*/
................................................................................
         "SET type='table', name=%Q, tbl_name=%Q, rootpage=0, sql=%Q "
       "WHERE rowid=#1",
      db->aDb[iDb].zName, SCHEMA_TABLE(iDb),
      pTab->zName,
      pTab->zName,
      zStmt
    );
    sqliteFree(zStmt);
    v = sqlite3GetVdbe(pParse);
    sqlite3ChangeCookie(db, v, iDb);

    sqlite3VdbeAddOp(v, OP_Expire, 0, 0);
    zWhere = sqlite3MPrintf("name='%q'", pTab->zName);
    sqlite3VdbeOp3(v, OP_ParseSchema, iDb, 1, zWhere, P3_DYNAMIC);
    sqlite3VdbeOp3(v, OP_VCreate, iDb, 0, pTab->zName, strlen(pTab->zName) + 1);
................................................................................
    *pzErr = sqlite3MPrintf(zFormat, pTab->zName);
    rc = SQLITE_ERROR;
  } 
  if( rc==SQLITE_OK ){
    rc = rc2;
  }
  db->pVTab = 0;
  sqliteFree(zModuleName);

  /* If everything went according to plan, loop through the columns
  ** of the table to see if any of them contain the token "hidden".
  ** If so, set the Column.isHidden flag and remove the token from
  ** the type string.
  */
  if( rc==SQLITE_OK ){
................................................................................
  } else {
    char *zErr = 0;
    sqlite3 *db = pParse->db;
    rc = vtabCallConstructor(db, pTab, pMod, pMod->pModule->xConnect, &zErr);
    if( rc!=SQLITE_OK ){
      sqlite3ErrorMsg(pParse, "%s", zErr);
    }
    sqliteFree(zErr);
  }

  return rc;
}

/*
** Add the virtual table pVtab to the array sqlite3.aVTrans[].
................................................................................
static int addToVTrans(sqlite3 *db, sqlite3_vtab *pVtab){
  const int ARRAY_INCR = 5;

  /* Grow the sqlite3.aVTrans array if required */
  if( (db->nVTrans%ARRAY_INCR)==0 ){
    sqlite3_vtab **aVTrans;
    int nBytes = sizeof(sqlite3_vtab *) * (db->nVTrans + ARRAY_INCR);
    aVTrans = sqliteRealloc((void *)db->aVTrans, nBytes);
    if( !aVTrans ){

      return SQLITE_NOMEM;
    }
    memset(&aVTrans[db->nVTrans], 0, sizeof(sqlite3_vtab *)*ARRAY_INCR);
    db->aVTrans = aVTrans;
  }

  /* Add pVtab to the end of sqlite3.aVTrans */
................................................................................

/*
** This function is invoked by the vdbe to call the xCreate method
** of the virtual table named zTab in database iDb. 
**
** If an error occurs, *pzErr is set to point an an English language
** description of the error and an SQLITE_XXX error code is returned.
** In this case the caller must call sqliteFree() on *pzErr.
*/
int sqlite3VtabCallCreate(sqlite3 *db, int iDb, const char *zTab, char **pzErr){
  int rc = SQLITE_OK;
  Table *pTab;
  Module *pMod;
  const char *zModule;

................................................................................
    pTab->aCol = sParse.pNewTable->aCol;
    pTab->nCol = sParse.pNewTable->nCol;
    sParse.pNewTable->nCol = 0;
    sParse.pNewTable->aCol = 0;
    db->pVTab = 0;
  } else {
    sqlite3Error(db, SQLITE_ERROR, zErr);
    sqliteFree(zErr);
    rc = SQLITE_ERROR;
  }
  sParse.declareVtab = 0;

  sqlite3_finalize((sqlite3_stmt*)sParse.pVdbe);
  sqlite3DeleteTable(sParse.pNewTable);
  sParse.pNewTable = 0;
................................................................................
    for(i=0; i<db->nVTrans && db->aVTrans[i]; i++){
      sqlite3_vtab *pVtab = db->aVTrans[i];
      int (*x)(sqlite3_vtab *);
      x = *(int (**)(sqlite3_vtab *))((char *)pVtab->pModule + offset);
      if( x ) x(pVtab);
      sqlite3VtabUnlock(db, pVtab);
    }
    sqliteFree(db->aVTrans);
    db->nVTrans = 0;
    db->aVTrans = 0;
  }
}

/*
** If argument rc2 is not SQLITE_OK, then return it and do nothing. 
................................................................................
** overload MATCH, LIKE, GLOB, and REGEXP operators.
**
** Return either the pDef argument (indicating no change) or a 
** new FuncDef structure that is marked as ephemeral using the
** SQLITE_FUNC_EPHEM flag.
*/
FuncDef *sqlite3VtabOverloadFunction(

  FuncDef *pDef,  /* Function to possibly overload */
  int nArg,       /* Number of arguments to the function */
  Expr *pExpr     /* First argument to the function */
){
  Table *pTab;
  sqlite3_vtab *pVtab;
  sqlite3_module *pMod;
................................................................................
  assert( pVtab->pModule!=0 );
  pMod = (sqlite3_module *)pVtab->pModule;
  if( pMod->xFindFunction==0 ) return pDef;
 
  /* Call the xFuncFunction method on the virtual table implementation
  ** to see if the implementation wants to overload this function 
  */
  zLowerName = sqlite3StrDup(pDef->zName);

  for(z=(unsigned char*)zLowerName; *z; z++){
    *z = sqlite3UpperToLower[*z];
  }
  rc = pMod->xFindFunction(pVtab, nArg, zLowerName, &xFunc, &pArg);
  sqliteFree(zLowerName);

  if( rc==0 ){
    return pDef;
  }

  /* Create a new ephemeral function definition for the overloaded
  ** function */
  pNew = sqliteMalloc( sizeof(*pNew) + strlen(pDef->zName) );
  if( pNew==0 ){
    return pDef;
  }
  *pNew = *pDef;
  memcpy(pNew->zName, pDef->zName, strlen(pDef->zName)+1);
  pNew->xFunc = xFunc;
  pNew->pUserData = pArg;
  pNew->flags |= SQLITE_FUNC_EPHEM;
  return pNew;
}

#endif /* SQLITE_OMIT_VIRTUALTABLE */

**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains code used to help implement virtual tables.
**
** $Id: vtab.c,v 1.49 2007/08/16 04:30:41 drh Exp $
*/
#ifndef SQLITE_OMIT_VIRTUALTABLE
#include "sqliteInt.h"

static int createModule(
  sqlite3 *db,                    /* Database in which module is registered */
  const char *zName,              /* Name assigned to this module */
  const sqlite3_module *pModule,  /* The definition of the module */
  void *pAux,                     /* Context pointer for xCreate/xConnect */
  void (*xDestroy)(void *)        /* Module destructor function */
) {
  int nName = strlen(zName);
  Module *pMod = (Module *)sqlite3DbMallocRaw(db, sizeof(Module) + nName + 1);
  if( pMod ){
    char *zCopy = (char *)(&pMod[1]);
    memcpy(zCopy, zName, nName+1);
    pMod->zName = zCopy;
    pMod->pModule = pModule;
    pMod->pAux = pAux;
    pMod->xDestroy = xDestroy;
    pMod = (Module *)sqlite3HashInsert(&db->aModule, zCopy, nName, (void*)pMod);
    if( pMod && pMod->xDestroy ){
      pMod->xDestroy(pMod->pAux);
    }
    sqlite3_free(pMod);
    sqlite3ResetInternalSchema(db, 0);
  }
  return sqlite3ApiExit(db, SQLITE_OK);
}


/*
................................................................................
    assert( p->pMod && p->pMod->pModule );
    sqlite3VtabUnlock(p->pSchema->db, pVtab);
    p->pVtab = 0;
  }
  if( p->azModuleArg ){
    int i;
    for(i=0; i<p->nModuleArg; i++){
      sqlite3_free(p->azModuleArg[i]);
    }
    sqlite3_free(p->azModuleArg);
  }
}

/*
** Add a new module argument to pTable->azModuleArg[].
** The string is not copied - the pointer is stored.  The
** string will be freed automatically when the table is
** deleted.
*/
static void addModuleArgument(sqlite3 *db, Table *pTable, char *zArg){
  int i = pTable->nModuleArg++;
  int nBytes = sizeof(char *)*(1+pTable->nModuleArg);
  char **azModuleArg;
  azModuleArg = sqlite3_realloc(pTable->azModuleArg, nBytes);
  if( azModuleArg==0 ){
    int j;
    for(j=0; j<i; j++){
      sqlite3_free(pTable->azModuleArg[j]);
    }
    sqlite3_free(zArg);
    sqlite3_free(pTable->azModuleArg);
    pTable->nModuleArg = 0;
    db->mallocFailed = 1;
  }else{
    azModuleArg[i] = zArg;
    azModuleArg[i+1] = 0;
  }
  pTable->azModuleArg = azModuleArg;
}

................................................................................
  Parse *pParse,        /* Parsing context */
  Token *pName1,        /* Name of new table, or database name */
  Token *pName2,        /* Name of new table or NULL */
  Token *pModuleName    /* Name of the module for the virtual table */
){
  int iDb;              /* The database the table is being created in */
  Table *pTable;        /* The new virtual table */
  sqlite3 *db;          /* Database connection */

#ifndef SQLITE_OMIT_SHARED_CACHE
  if( sqlite3ThreadDataReadOnly()->useSharedData ){
    sqlite3ErrorMsg(pParse, "Cannot use virtual tables in shared-cache mode");
    return;
  }
#endif

  sqlite3StartTable(pParse, pName1, pName2, 0, 0, 1, 0);
  pTable = pParse->pNewTable;
  if( pTable==0 || pParse->nErr ) return;
  assert( 0==pTable->pIndex );

  db = pParse->db;
  iDb = sqlite3SchemaToIndex(db, pTable->pSchema);
  assert( iDb>=0 );

  pTable->isVirtual = 1;
  pTable->nModuleArg = 0;
  addModuleArgument(db, pTable, sqlite3NameFromToken(db, pModuleName));
  addModuleArgument(db, pTable, sqlite3DbStrDup(db, db->aDb[iDb].zName));
  addModuleArgument(db, pTable, sqlite3DbStrDup(db, pTable->zName));
  pParse->sNameToken.n = pModuleName->z + pModuleName->n - pName1->z;

#ifndef SQLITE_OMIT_AUTHORIZATION
  /* Creating a virtual table invokes the authorization callback twice.
  ** The first invocation, to obtain permission to INSERT a row into the
  ** sqlite_master table, has already been made by sqlite3StartTable().
  ** The second call, to obtain permission to create the table, is made now.
................................................................................
** in pParse->zArg[] and appends it to the list of arguments on the
** virtual table currently under construction in pParse->pTable.
*/
static void addArgumentToVtab(Parse *pParse){
  if( pParse->sArg.z && pParse->pNewTable ){
    const char *z = (const char*)pParse->sArg.z;
    int n = pParse->sArg.n;
    sqlite3 *db = pParse->db;
    addModuleArgument(db, pParse->pNewTable, sqlite3DbStrNDup(db, z, n));
  }
}

/*
** The parser calls this routine after the CREATE VIRTUAL TABLE statement
** has been completely parsed.
*/
................................................................................
         "SET type='table', name=%Q, tbl_name=%Q, rootpage=0, sql=%Q "
       "WHERE rowid=#1",
      db->aDb[iDb].zName, SCHEMA_TABLE(iDb),
      pTab->zName,
      pTab->zName,
      zStmt
    );
    sqlite3_free(zStmt);
    v = sqlite3GetVdbe(pParse);
    sqlite3ChangeCookie(db, v, iDb);

    sqlite3VdbeAddOp(v, OP_Expire, 0, 0);
    zWhere = sqlite3MPrintf("name='%q'", pTab->zName);
    sqlite3VdbeOp3(v, OP_ParseSchema, iDb, 1, zWhere, P3_DYNAMIC);
    sqlite3VdbeOp3(v, OP_VCreate, iDb, 0, pTab->zName, strlen(pTab->zName) + 1);
................................................................................
    *pzErr = sqlite3MPrintf(zFormat, pTab->zName);
    rc = SQLITE_ERROR;
  } 
  if( rc==SQLITE_OK ){
    rc = rc2;
  }
  db->pVTab = 0;
  sqlite3_free(zModuleName);

  /* If everything went according to plan, loop through the columns
  ** of the table to see if any of them contain the token "hidden".
  ** If so, set the Column.isHidden flag and remove the token from
  ** the type string.
  */
  if( rc==SQLITE_OK ){
................................................................................
  } else {
    char *zErr = 0;
    sqlite3 *db = pParse->db;
    rc = vtabCallConstructor(db, pTab, pMod, pMod->pModule->xConnect, &zErr);
    if( rc!=SQLITE_OK ){
      sqlite3ErrorMsg(pParse, "%s", zErr);
    }
    sqlite3_free(zErr);
  }

  return rc;
}

/*
** Add the virtual table pVtab to the array sqlite3.aVTrans[].
................................................................................
static int addToVTrans(sqlite3 *db, sqlite3_vtab *pVtab){
  const int ARRAY_INCR = 5;

  /* Grow the sqlite3.aVTrans array if required */
  if( (db->nVTrans%ARRAY_INCR)==0 ){
    sqlite3_vtab **aVTrans;
    int nBytes = sizeof(sqlite3_vtab *) * (db->nVTrans + ARRAY_INCR);
    aVTrans = sqlite3_realloc((void *)db->aVTrans, nBytes);
    if( !aVTrans ){
      db->mallocFailed = 1;
      return SQLITE_NOMEM;
    }
    memset(&aVTrans[db->nVTrans], 0, sizeof(sqlite3_vtab *)*ARRAY_INCR);
    db->aVTrans = aVTrans;
  }

  /* Add pVtab to the end of sqlite3.aVTrans */
................................................................................

/*
** This function is invoked by the vdbe to call the xCreate method
** of the virtual table named zTab in database iDb. 
**
** If an error occurs, *pzErr is set to point an an English language
** description of the error and an SQLITE_XXX error code is returned.
** In this case the caller must call sqlite3_free() on *pzErr.
*/
int sqlite3VtabCallCreate(sqlite3 *db, int iDb, const char *zTab, char **pzErr){
  int rc = SQLITE_OK;
  Table *pTab;
  Module *pMod;
  const char *zModule;

................................................................................
    pTab->aCol = sParse.pNewTable->aCol;
    pTab->nCol = sParse.pNewTable->nCol;
    sParse.pNewTable->nCol = 0;
    sParse.pNewTable->aCol = 0;
    db->pVTab = 0;
  } else {
    sqlite3Error(db, SQLITE_ERROR, zErr);
    sqlite3_free(zErr);
    rc = SQLITE_ERROR;
  }
  sParse.declareVtab = 0;

  sqlite3_finalize((sqlite3_stmt*)sParse.pVdbe);
  sqlite3DeleteTable(sParse.pNewTable);
  sParse.pNewTable = 0;
................................................................................
    for(i=0; i<db->nVTrans && db->aVTrans[i]; i++){
      sqlite3_vtab *pVtab = db->aVTrans[i];
      int (*x)(sqlite3_vtab *);
      x = *(int (**)(sqlite3_vtab *))((char *)pVtab->pModule + offset);
      if( x ) x(pVtab);
      sqlite3VtabUnlock(db, pVtab);
    }
    sqlite3_free(db->aVTrans);
    db->nVTrans = 0;
    db->aVTrans = 0;
  }
}

/*
** If argument rc2 is not SQLITE_OK, then return it and do nothing. 
................................................................................
** overload MATCH, LIKE, GLOB, and REGEXP operators.
**
** Return either the pDef argument (indicating no change) or a 
** new FuncDef structure that is marked as ephemeral using the
** SQLITE_FUNC_EPHEM flag.
*/
FuncDef *sqlite3VtabOverloadFunction(
  sqlite3 *db,    /* Database connection for reporting malloc problems */
  FuncDef *pDef,  /* Function to possibly overload */
  int nArg,       /* Number of arguments to the function */
  Expr *pExpr     /* First argument to the function */
){
  Table *pTab;
  sqlite3_vtab *pVtab;
  sqlite3_module *pMod;
................................................................................
  assert( pVtab->pModule!=0 );
  pMod = (sqlite3_module *)pVtab->pModule;
  if( pMod->xFindFunction==0 ) return pDef;
 
  /* Call the xFuncFunction method on the virtual table implementation
  ** to see if the implementation wants to overload this function 
  */
  zLowerName = sqlite3DbStrDup(db, pDef->zName);
  if( zLowerName ){
    for(z=(unsigned char*)zLowerName; *z; z++){
      *z = sqlite3UpperToLower[*z];
    }
    rc = pMod->xFindFunction(pVtab, nArg, zLowerName, &xFunc, &pArg);
    sqlite3_free(zLowerName);
  }
  if( rc==0 ){
    return pDef;
  }

  /* Create a new ephemeral function definition for the overloaded
  ** function */
  pNew = sqlite3DbMallocZero(db, sizeof(*pNew) + strlen(pDef->zName) );
  if( pNew==0 ){
    return pDef;
  }
  *pNew = *pDef;
  memcpy(pNew->zName, pDef->zName, strlen(pDef->zName)+1);
  pNew->xFunc = xFunc;
  pNew->pUserData = pArg;
  pNew->flags |= SQLITE_FUNC_EPHEM;
  return pNew;
}

#endif /* SQLITE_OMIT_VIRTUALTABLE */

** This module contains C code that generates VDBE code used to process
** the WHERE clause of SQL statements.  This module is reponsible for
** generating the code that loops through a table looking for applicable
** rows.  Indices are selected and used to speed the search when doing
** so is applicable.  Because this module is responsible for selecting
** indices, you might also think of this module as the "query optimizer".
**
** $Id: where.c,v 1.254 2007/07/30 14:40:48 danielk1977 Exp $
*/
#include "sqliteInt.h"

/*
** The number of bits in a Bitmask.  "BMS" means "BitMask Size".
*/
#define BMS  (sizeof(Bitmask)*8)
................................................................................
  WhereTerm *a;
  for(i=pWC->nTerm-1, a=pWC->a; i>=0; i--, a++){
    if( a->flags & TERM_DYNAMIC ){
      sqlite3ExprDelete(a->pExpr);
    }
  }
  if( pWC->a!=pWC->aStatic ){
    sqliteFree(pWC->a);
  }
}

/*
** Add a new entries to the WhereClause structure.  Increase the allocated
** space as necessary.
**
................................................................................
** the pWC->a[] array.
*/
static int whereClauseInsert(WhereClause *pWC, Expr *p, int flags){
  WhereTerm *pTerm;
  int idx;
  if( pWC->nTerm>=pWC->nSlot ){
    WhereTerm *pOld = pWC->a;
    pWC->a = sqliteMalloc( sizeof(pWC->a[0])*pWC->nSlot*2 );
    if( pWC->a==0 ){

      if( flags & TERM_DYNAMIC ){
        sqlite3ExprDelete(p);
      }
      return 0;
    }
    memcpy(pWC->a, pOld, sizeof(pWC->a[0])*pWC->nTerm);
    if( pOld!=pWC->aStatic ){
      sqliteFree(pOld);
    }
    pWC->nSlot *= 2;
  }
  pTerm = &pWC->a[idx = pWC->nTerm];
  pWC->nTerm++;
  pTerm->pExpr = p;
  pTerm->flags = flags;
................................................................................
    */
    pColl = db->pDfltColl;
  }
  if( (pColl->type!=SQLITE_COLL_BINARY || noCase) &&
      (pColl->type!=SQLITE_COLL_NOCASE || !noCase) ){
    return 0;
  }
  sqlite3DequoteExpr(pRight);
  z = (char *)pRight->token.z;
  for(cnt=0; (c=z[cnt])!=0 && c!=wc[0] && c!=wc[1] && c!=wc[2]; cnt++){}
  if( cnt==0 || 255==(u8)z[cnt] ){
    return 0;
  }
  *pisComplete = z[cnt]==wc[0] && z[cnt+1]==0;
  *pnPattern = cnt;
................................................................................
  ExprMaskSet *pMaskSet = pWC->pMaskSet;
  Expr *pExpr = pTerm->pExpr;
  Bitmask prereqLeft;
  Bitmask prereqAll;
  int nPattern;
  int isComplete;
  int op;


  if( sqlite3MallocFailed() ) return;

  prereqLeft = exprTableUsage(pMaskSet, pExpr->pLeft);
  op = pExpr->op;
  if( op==TK_IN ){
    assert( pExpr->pRight==0 );
    pTerm->prereqRight = exprListTableUsage(pMaskSet, pExpr->pList)
                          | exprSelectTableUsage(pMaskSet, pExpr->pSelect);
  }else if( op==TK_ISNULL ){
................................................................................
      pTerm->eOperator = operatorMask(op);
    }
    if( pRight && pRight->op==TK_COLUMN ){
      WhereTerm *pNew;
      Expr *pDup;
      if( pTerm->leftCursor>=0 ){
        int idxNew;
        pDup = sqlite3ExprDup(pExpr);
        if( sqlite3MallocFailed() ){
          sqlite3ExprDelete(pDup);
          return;
        }
        idxNew = whereClauseInsert(pWC, pDup, TERM_VIRTUAL|TERM_DYNAMIC);
        if( idxNew==0 ) return;
        pNew = &pWC->a[idxNew];
        pNew->iParent = idxTerm;
................................................................................
    int i;
    static const u8 ops[] = {TK_GE, TK_LE};
    assert( pList!=0 );
    assert( pList->nExpr==2 );
    for(i=0; i<2; i++){
      Expr *pNewExpr;
      int idxNew;
      pNewExpr = sqlite3Expr(ops[i], sqlite3ExprDup(pExpr->pLeft),
                             sqlite3ExprDup(pList->a[i].pExpr), 0);
      idxNew = whereClauseInsert(pWC, pNewExpr, TERM_VIRTUAL|TERM_DYNAMIC);
      exprAnalyze(pSrc, pWC, idxNew);
      pTerm = &pWC->a[idxTerm];
      pWC->a[idxNew].iParent = idxTerm;
    }
    pTerm->nChild = 2;
  }
................................................................................
    }while( !ok && (sOr.a[j++].flags & TERM_COPIED)!=0 && j<2 );
    if( ok ){
      ExprList *pList = 0;
      Expr *pNew, *pDup;
      Expr *pLeft = 0;
      for(i=sOr.nTerm-1, pOrTerm=sOr.a; i>=0 && ok; i--, pOrTerm++){
        if( (pOrTerm->flags & TERM_OR_OK)==0 ) continue;
        pDup = sqlite3ExprDup(pOrTerm->pExpr->pRight);
        pList = sqlite3ExprListAppend(pList, pDup, 0);
        pLeft = pOrTerm->pExpr->pLeft;
      }
      assert( pLeft!=0 );
      pDup = sqlite3ExprDup(pLeft);
      pNew = sqlite3Expr(TK_IN, pDup, 0, 0);
      if( pNew ){
        int idxNew;
        transferJoinMarkings(pNew, pExpr);
        pNew->pList = pList;
        idxNew = whereClauseInsert(pWC, pNew, TERM_VIRTUAL|TERM_DYNAMIC);
        exprAnalyze(pSrc, pWC, idxNew);
................................................................................
  }
#endif /* SQLITE_OMIT_OR_OPTIMIZATION */

#ifndef SQLITE_OMIT_LIKE_OPTIMIZATION
  /* Add constraints to reduce the search space on a LIKE or GLOB
  ** operator.
  */
  if( isLikeOrGlob(pWC->pParse->db, pExpr, &nPattern, &isComplete) ){
    Expr *pLeft, *pRight;
    Expr *pStr1, *pStr2;
    Expr *pNewExpr1, *pNewExpr2;
    int idxNew1, idxNew2;

    pLeft = pExpr->pList->a[1].pExpr;
    pRight = pExpr->pList->a[0].pExpr;
    pStr1 = sqlite3Expr(TK_STRING, 0, 0, 0);
    if( pStr1 ){
      sqlite3TokenCopy(&pStr1->token, &pRight->token);
      pStr1->token.n = nPattern;
      pStr1->flags = EP_Dequoted;
    }
    pStr2 = sqlite3ExprDup(pStr1);
    if( pStr2 ){
      assert( pStr2->token.dyn );
      ++*(u8*)&pStr2->token.z[nPattern-1];
    }
    pNewExpr1 = sqlite3Expr(TK_GE, sqlite3ExprDup(pLeft), pStr1, 0);
    idxNew1 = whereClauseInsert(pWC, pNewExpr1, TERM_VIRTUAL|TERM_DYNAMIC);
    exprAnalyze(pSrc, pWC, idxNew1);
    pNewExpr2 = sqlite3Expr(TK_LT, sqlite3ExprDup(pLeft), pStr2, 0);
    idxNew2 = whereClauseInsert(pWC, pNewExpr2, TERM_VIRTUAL|TERM_DYNAMIC);
    exprAnalyze(pSrc, pWC, idxNew2);
    pTerm = &pWC->a[idxTerm];
    if( isComplete ){
      pWC->a[idxNew1].iParent = idxTerm;
      pWC->a[idxNew2].iParent = idxTerm;
      pTerm->nChild = 2;
................................................................................

    pRight = pExpr->pList->a[0].pExpr;
    pLeft = pExpr->pList->a[1].pExpr;
    prereqExpr = exprTableUsage(pMaskSet, pRight);
    prereqColumn = exprTableUsage(pMaskSet, pLeft);
    if( (prereqExpr & prereqColumn)==0 ){
      Expr *pNewExpr;
      pNewExpr = sqlite3Expr(TK_MATCH, 0, sqlite3ExprDup(pRight), 0);
      idxNew = whereClauseInsert(pWC, pNewExpr, TERM_VIRTUAL|TERM_DYNAMIC);
      pNewTerm = &pWC->a[idxNew];
      pNewTerm->prereqRight = prereqExpr;
      pNewTerm->leftCursor = pLeft->iTable;
      pNewTerm->leftColumn = pLeft->iColumn;
      pNewTerm->eOperator = WO_MATCH;
      pNewTerm->iParent = idxTerm;
................................................................................
      if( i==pOrderBy->nExpr ){
        nOrderBy = pOrderBy->nExpr;
      }
    }

    /* Allocate the sqlite3_index_info structure
    */
    pIdxInfo = sqliteMalloc( sizeof(*pIdxInfo)
                             + (sizeof(*pIdxCons) + sizeof(*pUsage))*nTerm
                             + sizeof(*pIdxOrderBy)*nOrderBy );
    if( pIdxInfo==0 ){

      sqlite3ErrorMsg(pParse, "out of memory");
      return 0.0;
    }
    *ppIdxInfo = pIdxInfo;

    /* Initialize the structure.  The sqlite3_index_info structure contains
    ** many fields that are declared "const" to prevent xBestIndex from
................................................................................
  sqlite3SafetyOff(pParse->db);
  WHERETRACE(("xBestIndex for %s\n", pTab->zName));
  TRACE_IDX_INPUTS(pIdxInfo);
  rc = pTab->pVtab->pModule->xBestIndex(pTab->pVtab, pIdxInfo);
  TRACE_IDX_OUTPUTS(pIdxInfo);
  if( rc!=SQLITE_OK ){
    if( rc==SQLITE_NOMEM ){
      sqlite3FailedMalloc();
    }else {
      sqlite3ErrorMsg(pParse, "%s", sqlite3ErrStr(rc));
    }
    sqlite3SafetyOn(pParse->db);
  }else{
    rc = sqlite3SafetyOn(pParse->db);
  }
................................................................................
    iTab = pX->iTable;
    sqlite3VdbeAddOp(v, OP_Rewind, iTab, 0);
    VdbeComment((v, "# %.*s", pX->span.n, pX->span.z));
    if( pLevel->nIn==0 ){
      pLevel->nxt = sqlite3VdbeMakeLabel(v);
    }
    pLevel->nIn++;
    pLevel->aInLoop = sqliteReallocOrFree(pLevel->aInLoop,
                                    sizeof(pLevel->aInLoop[0])*pLevel->nIn);
    pIn = pLevel->aInLoop;
    if( pIn ){
      pIn += pLevel->nIn - 1;
      pIn->iCur = iTab;
      pIn->topAddr = sqlite3VdbeAddOp(v, OP_Column, iTab, 0);
      sqlite3VdbeAddOp(v, OP_IsNull, -1, 0);
................................................................................
        if( pInfo->needToFreeIdxStr ){
          /* Coverage: Don't think this can be reached. By the time this
          ** function is called, the index-strings have been passed
          ** to the vdbe layer for deletion.
          */
          sqlite3_free(pInfo->idxStr);
        }
        sqliteFree(pInfo);
      }
    }
    sqliteFree(pWInfo);
  }
}


/*
** Generate the beginning of the loop used for WHERE clause processing.
** The return value is a pointer to an opaque structure that contains
................................................................................
  WhereTerm *pTerm;          /* A single term in the WHERE clause */
  ExprMaskSet maskSet;       /* The expression mask set */
  WhereClause wc;            /* The WHERE clause is divided into these terms */
  struct SrcList_item *pTabItem;  /* A single entry from pTabList */
  WhereLevel *pLevel;             /* A single level in the pWInfo list */
  int iFrom;                      /* First unused FROM clause element */
  int andFlags;              /* AND-ed combination of all wc.a[].flags */


  /* The number of tables in the FROM clause is limited by the number of
  ** bits in a Bitmask 
  */
  if( pTabList->nSrc>BMS ){
    sqlite3ErrorMsg(pParse, "at most %d tables in a join", BMS);
    return 0;
................................................................................
  initMaskSet(&maskSet);
  whereClauseInit(&wc, pParse, &maskSet);
  whereSplit(&wc, pWhere, TK_AND);
    
  /* Allocate and initialize the WhereInfo structure that will become the
  ** return value.
  */


  pWInfo = sqliteMalloc( sizeof(WhereInfo) + pTabList->nSrc*sizeof(WhereLevel));
  if( sqlite3MallocFailed() ){
    goto whereBeginNoMem;
  }
  pWInfo->nLevel = pTabList->nSrc;
  pWInfo->pParse = pParse;
  pWInfo->pTabList = pTabList;
  pWInfo->iBreak = sqlite3VdbeMakeLabel(v);

................................................................................
  ** want to analyze these virtual terms, so start analyzing at the end
  ** and work forward so that the added virtual terms are never processed.
  */
  for(i=0; i<pTabList->nSrc; i++){
    createMask(&maskSet, pTabList->a[i].iCursor);
  }
  exprAnalyzeAll(pTabList, &wc);
  if( sqlite3MallocFailed() ){
    goto whereBeginNoMem;
  }

  /* Chose the best index to use for each table in the FROM clause.
  **
  ** This loop fills in the following fields:
  **
................................................................................
      int j;
      sqlite3VdbeResolveLabel(v, pLevel->nxt);
      for(j=pLevel->nIn, pIn=&pLevel->aInLoop[j-1]; j>0; j--, pIn--){
        sqlite3VdbeJumpHere(v, pIn->topAddr+1);
        sqlite3VdbeAddOp(v, OP_Next, pIn->iCur, pIn->topAddr);
        sqlite3VdbeJumpHere(v, pIn->topAddr-1);
      }
      sqliteFree(pLevel->aInLoop);
    }
    sqlite3VdbeResolveLabel(v, pLevel->brk);
    if( pLevel->iLeftJoin ){
      int addr;
      addr = sqlite3VdbeAddOp(v, OP_IfMemPos, pLevel->iLeftJoin, 0);
      sqlite3VdbeAddOp(v, OP_NullRow, pTabList->a[i].iCursor, 0);
      if( pLevel->iIdxCur>=0 ){

** This module contains C code that generates VDBE code used to process
** the WHERE clause of SQL statements.  This module is reponsible for
** generating the code that loops through a table looking for applicable
** rows.  Indices are selected and used to speed the search when doing
** so is applicable.  Because this module is responsible for selecting
** indices, you might also think of this module as the "query optimizer".
**
** $Id: where.c,v 1.255 2007/08/16 04:30:41 drh Exp $
*/
#include "sqliteInt.h"

/*
** The number of bits in a Bitmask.  "BMS" means "BitMask Size".
*/
#define BMS  (sizeof(Bitmask)*8)
................................................................................
  WhereTerm *a;
  for(i=pWC->nTerm-1, a=pWC->a; i>=0; i--, a++){
    if( a->flags & TERM_DYNAMIC ){
      sqlite3ExprDelete(a->pExpr);
    }
  }
  if( pWC->a!=pWC->aStatic ){
    sqlite3_free(pWC->a);
  }
}

/*
** Add a new entries to the WhereClause structure.  Increase the allocated
** space as necessary.
**
................................................................................
** the pWC->a[] array.
*/
static int whereClauseInsert(WhereClause *pWC, Expr *p, int flags){
  WhereTerm *pTerm;
  int idx;
  if( pWC->nTerm>=pWC->nSlot ){
    WhereTerm *pOld = pWC->a;
    pWC->a = sqlite3_malloc( sizeof(pWC->a[0])*pWC->nSlot*2 );
    if( pWC->a==0 ){
      pWC->pParse->db->mallocFailed = 1;
      if( flags & TERM_DYNAMIC ){
        sqlite3ExprDelete(p);
      }
      return 0;
    }
    memcpy(pWC->a, pOld, sizeof(pWC->a[0])*pWC->nTerm);
    if( pOld!=pWC->aStatic ){
      sqlite3_free(pOld);
    }
    pWC->nSlot *= 2;
  }
  pTerm = &pWC->a[idx = pWC->nTerm];
  pWC->nTerm++;
  pTerm->pExpr = p;
  pTerm->flags = flags;
................................................................................
    */
    pColl = db->pDfltColl;
  }
  if( (pColl->type!=SQLITE_COLL_BINARY || noCase) &&
      (pColl->type!=SQLITE_COLL_NOCASE || !noCase) ){
    return 0;
  }
  sqlite3DequoteExpr(db, pRight);
  z = (char *)pRight->token.z;
  for(cnt=0; (c=z[cnt])!=0 && c!=wc[0] && c!=wc[1] && c!=wc[2]; cnt++){}
  if( cnt==0 || 255==(u8)z[cnt] ){
    return 0;
  }
  *pisComplete = z[cnt]==wc[0] && z[cnt+1]==0;
  *pnPattern = cnt;
................................................................................
  ExprMaskSet *pMaskSet = pWC->pMaskSet;
  Expr *pExpr = pTerm->pExpr;
  Bitmask prereqLeft;
  Bitmask prereqAll;
  int nPattern;
  int isComplete;
  int op;
  sqlite3 *db = pWC->pParse->db;


  if( db->mallocFailed ) return;
  prereqLeft = exprTableUsage(pMaskSet, pExpr->pLeft);
  op = pExpr->op;
  if( op==TK_IN ){
    assert( pExpr->pRight==0 );
    pTerm->prereqRight = exprListTableUsage(pMaskSet, pExpr->pList)
                          | exprSelectTableUsage(pMaskSet, pExpr->pSelect);
  }else if( op==TK_ISNULL ){
................................................................................
      pTerm->eOperator = operatorMask(op);
    }
    if( pRight && pRight->op==TK_COLUMN ){
      WhereTerm *pNew;
      Expr *pDup;
      if( pTerm->leftCursor>=0 ){
        int idxNew;
        pDup = sqlite3ExprDup(db, pExpr);
        if( db->mallocFailed ){
          sqlite3ExprDelete(pDup);
          return;
        }
        idxNew = whereClauseInsert(pWC, pDup, TERM_VIRTUAL|TERM_DYNAMIC);
        if( idxNew==0 ) return;
        pNew = &pWC->a[idxNew];
        pNew->iParent = idxTerm;
................................................................................
    int i;
    static const u8 ops[] = {TK_GE, TK_LE};
    assert( pList!=0 );
    assert( pList->nExpr==2 );
    for(i=0; i<2; i++){
      Expr *pNewExpr;
      int idxNew;
      pNewExpr = sqlite3Expr(ops[i], sqlite3ExprDup(db, pExpr->pLeft),
                             sqlite3ExprDup(db, pList->a[i].pExpr), 0);
      idxNew = whereClauseInsert(pWC, pNewExpr, TERM_VIRTUAL|TERM_DYNAMIC);
      exprAnalyze(pSrc, pWC, idxNew);
      pTerm = &pWC->a[idxTerm];
      pWC->a[idxNew].iParent = idxTerm;
    }
    pTerm->nChild = 2;
  }
................................................................................
    }while( !ok && (sOr.a[j++].flags & TERM_COPIED)!=0 && j<2 );
    if( ok ){
      ExprList *pList = 0;
      Expr *pNew, *pDup;
      Expr *pLeft = 0;
      for(i=sOr.nTerm-1, pOrTerm=sOr.a; i>=0 && ok; i--, pOrTerm++){
        if( (pOrTerm->flags & TERM_OR_OK)==0 ) continue;
        pDup = sqlite3ExprDup(db, pOrTerm->pExpr->pRight);
        pList = sqlite3ExprListAppend(pWC->pParse, pList, pDup, 0);
        pLeft = pOrTerm->pExpr->pLeft;
      }
      assert( pLeft!=0 );
      pDup = sqlite3ExprDup(db, pLeft);
      pNew = sqlite3Expr(TK_IN, pDup, 0, 0);
      if( pNew ){
        int idxNew;
        transferJoinMarkings(pNew, pExpr);
        pNew->pList = pList;
        idxNew = whereClauseInsert(pWC, pNew, TERM_VIRTUAL|TERM_DYNAMIC);
        exprAnalyze(pSrc, pWC, idxNew);
................................................................................
  }
#endif /* SQLITE_OMIT_OR_OPTIMIZATION */

#ifndef SQLITE_OMIT_LIKE_OPTIMIZATION
  /* Add constraints to reduce the search space on a LIKE or GLOB
  ** operator.
  */
  if( isLikeOrGlob(db, pExpr, &nPattern, &isComplete) ){
    Expr *pLeft, *pRight;
    Expr *pStr1, *pStr2;
    Expr *pNewExpr1, *pNewExpr2;
    int idxNew1, idxNew2;

    pLeft = pExpr->pList->a[1].pExpr;
    pRight = pExpr->pList->a[0].pExpr;
    pStr1 = sqlite3PExpr(pParse, TK_STRING, 0, 0, 0);
    if( pStr1 ){
      sqlite3TokenCopy(db, &pStr1->token, &pRight->token);
      pStr1->token.n = nPattern;
      pStr1->flags = EP_Dequoted;
    }
    pStr2 = sqlite3ExprDup(db, pStr1);
    if( pStr2 ){
      assert( pStr2->token.dyn );
      ++*(u8*)&pStr2->token.z[nPattern-1];
    }
    pNewExpr1 = sqlite3PExpr(pParse, TK_GE, sqlite3ExprDup(db,pLeft), pStr1, 0);
    idxNew1 = whereClauseInsert(pWC, pNewExpr1, TERM_VIRTUAL|TERM_DYNAMIC);
    exprAnalyze(pSrc, pWC, idxNew1);
    pNewExpr2 = sqlite3PExpr(pParse, TK_LT, sqlite3ExprDup(db,pLeft), pStr2, 0);
    idxNew2 = whereClauseInsert(pWC, pNewExpr2, TERM_VIRTUAL|TERM_DYNAMIC);
    exprAnalyze(pSrc, pWC, idxNew2);
    pTerm = &pWC->a[idxTerm];
    if( isComplete ){
      pWC->a[idxNew1].iParent = idxTerm;
      pWC->a[idxNew2].iParent = idxTerm;
      pTerm->nChild = 2;
................................................................................

    pRight = pExpr->pList->a[0].pExpr;
    pLeft = pExpr->pList->a[1].pExpr;
    prereqExpr = exprTableUsage(pMaskSet, pRight);
    prereqColumn = exprTableUsage(pMaskSet, pLeft);
    if( (prereqExpr & prereqColumn)==0 ){
      Expr *pNewExpr;
      pNewExpr = sqlite3Expr(TK_MATCH, 0, sqlite3ExprDup(db, pRight), 0);
      idxNew = whereClauseInsert(pWC, pNewExpr, TERM_VIRTUAL|TERM_DYNAMIC);
      pNewTerm = &pWC->a[idxNew];
      pNewTerm->prereqRight = prereqExpr;
      pNewTerm->leftCursor = pLeft->iTable;
      pNewTerm->leftColumn = pLeft->iColumn;
      pNewTerm->eOperator = WO_MATCH;
      pNewTerm->iParent = idxTerm;
................................................................................
      if( i==pOrderBy->nExpr ){
        nOrderBy = pOrderBy->nExpr;
      }
    }

    /* Allocate the sqlite3_index_info structure
    */
    pIdxInfo = sqlite3_malloc( sizeof(*pIdxInfo)
                             + (sizeof(*pIdxCons) + sizeof(*pUsage))*nTerm
                             + sizeof(*pIdxOrderBy)*nOrderBy );
    if( pIdxInfo==0 ){
      pParse->db->mallocFailed = 1;
      sqlite3ErrorMsg(pParse, "out of memory");
      return 0.0;
    }
    *ppIdxInfo = pIdxInfo;

    /* Initialize the structure.  The sqlite3_index_info structure contains
    ** many fields that are declared "const" to prevent xBestIndex from
................................................................................
  sqlite3SafetyOff(pParse->db);
  WHERETRACE(("xBestIndex for %s\n", pTab->zName));
  TRACE_IDX_INPUTS(pIdxInfo);
  rc = pTab->pVtab->pModule->xBestIndex(pTab->pVtab, pIdxInfo);
  TRACE_IDX_OUTPUTS(pIdxInfo);
  if( rc!=SQLITE_OK ){
    if( rc==SQLITE_NOMEM ){
      pParse->db->mallocFailed = 1;
    }else {
      sqlite3ErrorMsg(pParse, "%s", sqlite3ErrStr(rc));
    }
    sqlite3SafetyOn(pParse->db);
  }else{
    rc = sqlite3SafetyOn(pParse->db);
  }
................................................................................
    iTab = pX->iTable;
    sqlite3VdbeAddOp(v, OP_Rewind, iTab, 0);
    VdbeComment((v, "# %.*s", pX->span.n, pX->span.z));
    if( pLevel->nIn==0 ){
      pLevel->nxt = sqlite3VdbeMakeLabel(v);
    }
    pLevel->nIn++;
    pLevel->aInLoop = sqlite3DbReallocOrFree(pParse->db, pLevel->aInLoop,
                                    sizeof(pLevel->aInLoop[0])*pLevel->nIn);
    pIn = pLevel->aInLoop;
    if( pIn ){
      pIn += pLevel->nIn - 1;
      pIn->iCur = iTab;
      pIn->topAddr = sqlite3VdbeAddOp(v, OP_Column, iTab, 0);
      sqlite3VdbeAddOp(v, OP_IsNull, -1, 0);
................................................................................
        if( pInfo->needToFreeIdxStr ){
          /* Coverage: Don't think this can be reached. By the time this
          ** function is called, the index-strings have been passed
          ** to the vdbe layer for deletion.
          */
          sqlite3_free(pInfo->idxStr);
        }
        sqlite3_free(pInfo);
      }
    }
    sqlite3_free(pWInfo);
  }
}


/*
** Generate the beginning of the loop used for WHERE clause processing.
** The return value is a pointer to an opaque structure that contains
................................................................................
  WhereTerm *pTerm;          /* A single term in the WHERE clause */
  ExprMaskSet maskSet;       /* The expression mask set */
  WhereClause wc;            /* The WHERE clause is divided into these terms */
  struct SrcList_item *pTabItem;  /* A single entry from pTabList */
  WhereLevel *pLevel;             /* A single level in the pWInfo list */
  int iFrom;                      /* First unused FROM clause element */
  int andFlags;              /* AND-ed combination of all wc.a[].flags */
  sqlite3 *db;               /* Database connection */

  /* The number of tables in the FROM clause is limited by the number of
  ** bits in a Bitmask 
  */
  if( pTabList->nSrc>BMS ){
    sqlite3ErrorMsg(pParse, "at most %d tables in a join", BMS);
    return 0;
................................................................................
  initMaskSet(&maskSet);
  whereClauseInit(&wc, pParse, &maskSet);
  whereSplit(&wc, pWhere, TK_AND);
    
  /* Allocate and initialize the WhereInfo structure that will become the
  ** return value.
  */
  db = pParse->db;
  pWInfo = sqlite3DbMallocZero(db,  
                      sizeof(WhereInfo) + pTabList->nSrc*sizeof(WhereLevel));
  if( db->mallocFailed ){
    goto whereBeginNoMem;
  }
  pWInfo->nLevel = pTabList->nSrc;
  pWInfo->pParse = pParse;
  pWInfo->pTabList = pTabList;
  pWInfo->iBreak = sqlite3VdbeMakeLabel(v);

................................................................................
  ** want to analyze these virtual terms, so start analyzing at the end
  ** and work forward so that the added virtual terms are never processed.
  */
  for(i=0; i<pTabList->nSrc; i++){
    createMask(&maskSet, pTabList->a[i].iCursor);
  }
  exprAnalyzeAll(pTabList, &wc);
  if( db->mallocFailed ){
    goto whereBeginNoMem;
  }

  /* Chose the best index to use for each table in the FROM clause.
  **
  ** This loop fills in the following fields:
  **
................................................................................
      int j;
      sqlite3VdbeResolveLabel(v, pLevel->nxt);
      for(j=pLevel->nIn, pIn=&pLevel->aInLoop[j-1]; j>0; j--, pIn--){
        sqlite3VdbeJumpHere(v, pIn->topAddr+1);
        sqlite3VdbeAddOp(v, OP_Next, pIn->iCur, pIn->topAddr);
        sqlite3VdbeJumpHere(v, pIn->topAddr-1);
      }
      sqlite3_free(pLevel->aInLoop);
    }
    sqlite3VdbeResolveLabel(v, pLevel->brk);
    if( pLevel->iLeftJoin ){
      int addr;
      addr = sqlite3VdbeAddOp(v, OP_IfMemPos, pLevel->iLeftJoin, 0);
      sqlite3VdbeAddOp(v, OP_NullRow, pTabList->a[i].iCursor, 0);
      if( pLevel->iIdxCur>=0 ){