** triggers. Don't use IN(...) in case SQLITE_OMIT_SUBQUERY is defined. 
  */
  if( (zWhere=whereTempTriggers(pParse, pTab))!=0 ){
    sqlite3VdbeAddOp4(v, OP_ParseSchema, 1, 0, 0, zWhere, P4_DYNAMIC);
  }
#endif
}

















/*
** Generate code to implement the "ALTER TABLE xxx RENAME TO yyy" 
** command. 
*/
void sqlite3AlterRenameTable(
  Parse *pParse,            /* Parser context. */
................................................................................
        "there is already another table or index with this name: %s", zName);
    goto exit_rename_table;
  }

  /* Make sure it is not a system table being altered, or a reserved name
  ** that the table is being renamed to.
  */
  if( sqlite3Strlen30(pTab->zName)>6 
   && 0==sqlite3StrNICmp(pTab->zName, "sqlite_", 7)
  ){
    sqlite3ErrorMsg(pParse, "table %s may not be altered", pTab->zName);
    goto exit_rename_table;
  }
  if( SQLITE_OK!=sqlite3CheckObjectName(pParse, zName) ){
    goto exit_rename_table;
  }

#ifndef SQLITE_OMIT_VIEW
  if( pTab->pSelect ){
    sqlite3ErrorMsg(pParse, "view %s may not be altered", pTab->zName);
    goto exit_rename_table;
  }
................................................................................
  }
#endif

  /* 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.  But modify

  ** triggers. Don't use IN(...) in case SQLITE_OMIT_SUBQUERY is defined. 
  */
  if( (zWhere=whereTempTriggers(pParse, pTab))!=0 ){
    sqlite3VdbeAddOp4(v, OP_ParseSchema, 1, 0, 0, zWhere, P4_DYNAMIC);
  }
#endif
}

/*
** Parameter zName is the name of a table that is about to be altered
** (either with ALTER TABLE ... RENAME TO or ALTER TABLE ... ADD COLUMN).
** If the table is a system table, this function leaves an error message
** in pParse->zErr (system tables may not be altered) and returns non-zero.
**
** Or, if zName is not a system table, zero is returned.
*/
static int isSystemTable(Parse *pParse, const char *zName){
  if( sqlite3Strlen30(zName)>6 && 0==sqlite3StrNICmp(zName, "sqlite_", 7) ){
    sqlite3ErrorMsg(pParse, "table %s may not be altered", zName);
    return 1;
  }
  return 0;
}

/*
** Generate code to implement the "ALTER TABLE xxx RENAME TO yyy" 
** command. 
*/
void sqlite3AlterRenameTable(
  Parse *pParse,            /* Parser context. */
................................................................................
        "there is already another table or index with this name: %s", zName);
    goto exit_rename_table;
  }

  /* Make sure it is not a system table being altered, or a reserved name
  ** that the table is being renamed to.
  */
  if( SQLITE_OK!=isSystemTable(pParse, pTab->zName) ){



    goto exit_rename_table;
  }
  if( SQLITE_OK!=sqlite3CheckObjectName(pParse, zName) ){ goto
    exit_rename_table;
  }

#ifndef SQLITE_OMIT_VIEW
  if( pTab->pSelect ){
    sqlite3ErrorMsg(pParse, "view %s may not be altered", pTab->zName);
    goto exit_rename_table;
  }
................................................................................
  }
#endif

  /* 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;
  }
  if( SQLITE_OK!=isSystemTable(pParse, pTab->zName) ){
    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.  But modify

** with the named table are deleted. If zWhere==0, then code is generated
** to delete all stat table entries.
*/
static void openStatTable(
  Parse *pParse,          /* Parsing context */
  int iDb,                /* The database we are looking in */
  int iStatCur,           /* Open the sqlite_stat1 table on this cursor */
  const char *zWhere      /* Delete entries associated with this table */

){
  static const struct {
    const char *zName;
    const char *zCols;
  } aTable[] = {
    { "sqlite_stat1", "tbl,idx,stat" },
#ifdef SQLITE_ENABLE_STAT2
................................................................................
      /* The table already exists. If zWhere is not NULL, delete all entries 
      ** associated with the table zWhere. If zWhere is NULL, delete the
      ** entire contents of the table. */
      aRoot[i] = pStat->tnum;
      sqlite3TableLock(pParse, iDb, aRoot[i], 1, zTab);
      if( zWhere ){
        sqlite3NestedParse(pParse,
           "DELETE FROM %Q.%s WHERE tbl=%Q", pDb->zName, zTab, zWhere
        );
      }else{
        /* The sqlite_stat[12] table already exists.  Delete all rows. */
        sqlite3VdbeAddOp2(v, OP_Clear, aRoot[i], iDb);
      }
    }
  }
................................................................................
/*
** Generate code to do an analysis of all indices associated with
** a single table.
*/
static void analyzeOneTable(
  Parse *pParse,   /* Parser context */
  Table *pTab,     /* Table whose indices are to be analyzed */

  int iStatCur,    /* Index of VdbeCursor that writes the sqlite_stat1 table */
  int iMem         /* Available memory locations begin here */
){
  sqlite3 *db = pParse->db;    /* Database handle */
  Index *pIdx;                 /* An index to being analyzed */
  int iIdxCur;                 /* Cursor open on index being analyzed */
  Vdbe *v;                     /* The virtual machine being built up */
  int i;                       /* Loop counter */
  int topOfLoop;               /* The top of the loop */
  int endOfLoop;               /* The end of the loop */
  int addr = 0;                /* The address of an instruction */
  int jZeroRows = 0;           /* Jump from here if number of rows is zero */
  int iDb;                     /* Index of database containing pTab */
  int regTabname = iMem++;     /* Register containing table name */
  int regIdxname = iMem++;     /* Register containing index name */
  int regSampleno = iMem++;    /* Register containing next sample number */
  int regCol = iMem++;         /* Content of a column analyzed table */
  int regRec = iMem++;         /* Register holding completed record */
  int regTemp = iMem++;        /* Temporary use register */
  int regRowid = iMem++;       /* Rowid for the inserted record */

#ifdef SQLITE_ENABLE_STAT2

  int regTemp2 = iMem++;       /* Temporary use register */
  int regSamplerecno = iMem++; /* Index of next sample to record */
  int regRecno = iMem++;       /* Current sample index */
  int regLast = iMem++;        /* Index of last sample to record */
  int regFirst = iMem++;       /* Index of first sample to record */
#endif

................................................................................

  /* Establish a read-lock on the table at the shared-cache level. */
  sqlite3TableLock(pParse, iDb, pTab->tnum, 0, pTab->zName);

  iIdxCur = pParse->nTab++;
  sqlite3VdbeAddOp4(v, OP_String8, 0, regTabname, 0, pTab->zName, 0);
  for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
    int nCol = pIdx->nColumn;
    KeyInfo *pKey = sqlite3IndexKeyinfo(pParse, pIdx);




    if( iMem+1+(nCol*2)>pParse->nMem ){
      pParse->nMem = iMem+1+(nCol*2);
    }

    /* Open a cursor to the index to be analyzed. */
    assert( iDb==sqlite3SchemaToIndex(db, pIdx->pSchema) );
    sqlite3VdbeAddOp4(v, OP_OpenRead, iIdxCur, pIdx->tnum, iDb,
................................................................................
    **        I = (K+D-1)/D
    **
    ** If K==0 then no entry is made into the sqlite_stat1 table.  
    ** If K>0 then it is always the case the D>0 so division by zero
    ** is never possible.
    */
    sqlite3VdbeAddOp2(v, OP_SCopy, iMem, regSampleno);
    if( jZeroRows==0 ){
      jZeroRows = sqlite3VdbeAddOp1(v, OP_IfNot, iMem);
    }
    for(i=0; i<nCol; i++){
      sqlite3VdbeAddOp4(v, OP_String8, 0, regTemp, 0, " ", 0);
      sqlite3VdbeAddOp3(v, OP_Concat, regTemp, regSampleno, regSampleno);
      sqlite3VdbeAddOp3(v, OP_Add, iMem, iMem+i+1, regTemp);
      sqlite3VdbeAddOp2(v, OP_AddImm, regTemp, -1);
................................................................................
  ** containing NULL as the index name and the row count as the content.
  */
  if( pTab->pIndex==0 ){
    sqlite3VdbeAddOp3(v, OP_OpenRead, iIdxCur, pTab->tnum, iDb);
    VdbeComment((v, "%s", pTab->zName));
    sqlite3VdbeAddOp2(v, OP_Count, iIdxCur, regSampleno);
    sqlite3VdbeAddOp1(v, OP_Close, iIdxCur);

  }else{
    assert( jZeroRows>0 );
    addr = sqlite3VdbeAddOp0(v, OP_Goto);
    sqlite3VdbeJumpHere(v, jZeroRows);

  }
  sqlite3VdbeAddOp2(v, OP_Null, 0, regIdxname);
  sqlite3VdbeAddOp4(v, OP_MakeRecord, regTabname, 3, regRec, "aaa", 0);
  sqlite3VdbeAddOp2(v, OP_NewRowid, iStatCur, regRowid);
  sqlite3VdbeAddOp3(v, OP_Insert, iStatCur, regRec, regRowid);
  sqlite3VdbeChangeP5(v, OPFLAG_APPEND);
  if( pParse->nMem<regRec ) pParse->nMem = regRec;
  if( jZeroRows ){
    sqlite3VdbeJumpHere(v, addr);
  }
}

/*
** Generate code that will cause the most recent index analysis to
** be loaded into internal hash tables where is can be used.
*/
static void loadAnalysis(Parse *pParse, int iDb){
................................................................................
  HashElem *k;
  int iStatCur;
  int iMem;

  sqlite3BeginWriteOperation(pParse, 0, iDb);
  iStatCur = pParse->nTab;
  pParse->nTab += 2;
  openStatTable(pParse, iDb, iStatCur, 0);
  iMem = pParse->nMem+1;
  for(k=sqliteHashFirst(&pSchema->tblHash); k; k=sqliteHashNext(k)){
    Table *pTab = (Table*)sqliteHashData(k);
    analyzeOneTable(pParse, pTab, iStatCur, iMem);
  }
  loadAnalysis(pParse, iDb);
}

/*
** Generate code that will do an analysis of a single table in
** a database.

*/
static void analyzeTable(Parse *pParse, Table *pTab){
  int iDb;
  int iStatCur;

  assert( pTab!=0 );
  assert( sqlite3BtreeHoldsAllMutexes(pParse->db) );
  iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema);
  sqlite3BeginWriteOperation(pParse, 0, iDb);
  iStatCur = pParse->nTab;
  pParse->nTab += 2;



  openStatTable(pParse, iDb, iStatCur, pTab->zName);

  analyzeOneTable(pParse, pTab, iStatCur, pParse->nMem+1);
  loadAnalysis(pParse, iDb);
}

/*
** Generate code for the ANALYZE command.  The parser calls this routine
** when it recognizes an ANALYZE command.
**
................................................................................
*/
void sqlite3Analyze(Parse *pParse, Token *pName1, Token *pName2){
  sqlite3 *db = pParse->db;
  int iDb;
  int i;
  char *z, *zDb;
  Table *pTab;

  Token *pTableName;

  /* Read the database schema. If an error occurs, leave an error message
  ** and code in pParse and return NULL. */
  assert( sqlite3BtreeHoldsAllMutexes(pParse->db) );
  if( SQLITE_OK!=sqlite3ReadSchema(pParse) ){
    return;
................................................................................
    /* Form 2:  Analyze the database or table named */
    iDb = sqlite3FindDb(db, pName1);
    if( iDb>=0 ){
      analyzeDatabase(pParse, iDb);
    }else{
      z = sqlite3NameFromToken(db, pName1);
      if( z ){


        pTab = sqlite3LocateTable(pParse, 0, z, 0);
        sqlite3DbFree(db, 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, 0, z, zDb);
        sqlite3DbFree(db, z);
        if( pTab ){
          analyzeTable(pParse, pTab);
        }

      }
    }   
  }
}

/*
** Used to pass information from the analyzer reader through to the

** with the named table are deleted. If zWhere==0, then code is generated
** to delete all stat table entries.
*/
static void openStatTable(
  Parse *pParse,          /* Parsing context */
  int iDb,                /* The database we are looking in */
  int iStatCur,           /* Open the sqlite_stat1 table on this cursor */
  const char *zWhere,     /* Delete entries for this table or index */
  const char *zWhereType  /* Either "tbl" or "idx" */
){
  static const struct {
    const char *zName;
    const char *zCols;
  } aTable[] = {
    { "sqlite_stat1", "tbl,idx,stat" },
#ifdef SQLITE_ENABLE_STAT2
................................................................................
      /* The table already exists. If zWhere is not NULL, delete all entries 
      ** associated with the table zWhere. If zWhere is NULL, delete the
      ** entire contents of the table. */
      aRoot[i] = pStat->tnum;
      sqlite3TableLock(pParse, iDb, aRoot[i], 1, zTab);
      if( zWhere ){
        sqlite3NestedParse(pParse,
           "DELETE FROM %Q.%s WHERE %s=%Q", pDb->zName, zTab, zWhereType, zWhere
        );
      }else{
        /* The sqlite_stat[12] table already exists.  Delete all rows. */
        sqlite3VdbeAddOp2(v, OP_Clear, aRoot[i], iDb);
      }
    }
  }
................................................................................
/*
** Generate code to do an analysis of all indices associated with
** a single table.
*/
static void analyzeOneTable(
  Parse *pParse,   /* Parser context */
  Table *pTab,     /* Table whose indices are to be analyzed */
  Index *pOnlyIdx, /* If not NULL, only analyze this one index */
  int iStatCur,    /* Index of VdbeCursor that writes the sqlite_stat1 table */
  int iMem         /* Available memory locations begin here */
){
  sqlite3 *db = pParse->db;    /* Database handle */
  Index *pIdx;                 /* An index to being analyzed */
  int iIdxCur;                 /* Cursor open on index being analyzed */
  Vdbe *v;                     /* The virtual machine being built up */
  int i;                       /* Loop counter */
  int topOfLoop;               /* The top of the loop */
  int endOfLoop;               /* The end of the loop */

  int jZeroRows = -1;          /* Jump from here if number of rows is zero */
  int iDb;                     /* Index of database containing pTab */
  int regTabname = iMem++;     /* Register containing table name */
  int regIdxname = iMem++;     /* Register containing index name */
  int regSampleno = iMem++;    /* Register containing next sample number */
  int regCol = iMem++;         /* Content of a column analyzed table */
  int regRec = iMem++;         /* Register holding completed record */
  int regTemp = iMem++;        /* Temporary use register */
  int regRowid = iMem++;       /* Rowid for the inserted record */

#ifdef SQLITE_ENABLE_STAT2
  int addr = 0;                /* Instruction address */
  int regTemp2 = iMem++;       /* Temporary use register */
  int regSamplerecno = iMem++; /* Index of next sample to record */
  int regRecno = iMem++;       /* Current sample index */
  int regLast = iMem++;        /* Index of last sample to record */
  int regFirst = iMem++;       /* Index of first sample to record */
#endif

................................................................................

  /* Establish a read-lock on the table at the shared-cache level. */
  sqlite3TableLock(pParse, iDb, pTab->tnum, 0, pTab->zName);

  iIdxCur = pParse->nTab++;
  sqlite3VdbeAddOp4(v, OP_String8, 0, regTabname, 0, pTab->zName, 0);
  for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
    int nCol;
    KeyInfo *pKey;

    if( pOnlyIdx && pOnlyIdx!=pIdx ) continue;
    nCol = pIdx->nColumn;
    pKey = sqlite3IndexKeyinfo(pParse, pIdx);
    if( iMem+1+(nCol*2)>pParse->nMem ){
      pParse->nMem = iMem+1+(nCol*2);
    }

    /* Open a cursor to the index to be analyzed. */
    assert( iDb==sqlite3SchemaToIndex(db, pIdx->pSchema) );
    sqlite3VdbeAddOp4(v, OP_OpenRead, iIdxCur, pIdx->tnum, iDb,
................................................................................
    **        I = (K+D-1)/D
    **
    ** If K==0 then no entry is made into the sqlite_stat1 table.  
    ** If K>0 then it is always the case the D>0 so division by zero
    ** is never possible.
    */
    sqlite3VdbeAddOp2(v, OP_SCopy, iMem, regSampleno);
    if( jZeroRows<0 ){
      jZeroRows = sqlite3VdbeAddOp1(v, OP_IfNot, iMem);
    }
    for(i=0; i<nCol; i++){
      sqlite3VdbeAddOp4(v, OP_String8, 0, regTemp, 0, " ", 0);
      sqlite3VdbeAddOp3(v, OP_Concat, regTemp, regSampleno, regSampleno);
      sqlite3VdbeAddOp3(v, OP_Add, iMem, iMem+i+1, regTemp);
      sqlite3VdbeAddOp2(v, OP_AddImm, regTemp, -1);
................................................................................
  ** containing NULL as the index name and the row count as the content.
  */
  if( pTab->pIndex==0 ){
    sqlite3VdbeAddOp3(v, OP_OpenRead, iIdxCur, pTab->tnum, iDb);
    VdbeComment((v, "%s", pTab->zName));
    sqlite3VdbeAddOp2(v, OP_Count, iIdxCur, regSampleno);
    sqlite3VdbeAddOp1(v, OP_Close, iIdxCur);
    jZeroRows = sqlite3VdbeAddOp1(v, OP_IfNot, regSampleno);
  }else{


    sqlite3VdbeJumpHere(v, jZeroRows);
    jZeroRows = sqlite3VdbeAddOp0(v, OP_Goto);
  }
  sqlite3VdbeAddOp2(v, OP_Null, 0, regIdxname);
  sqlite3VdbeAddOp4(v, OP_MakeRecord, regTabname, 3, regRec, "aaa", 0);
  sqlite3VdbeAddOp2(v, OP_NewRowid, iStatCur, regRowid);
  sqlite3VdbeAddOp3(v, OP_Insert, iStatCur, regRec, regRowid);
  sqlite3VdbeChangeP5(v, OPFLAG_APPEND);
  if( pParse->nMem<regRec ) pParse->nMem = regRec;

  sqlite3VdbeJumpHere(v, jZeroRows);

}

/*
** Generate code that will cause the most recent index analysis to
** be loaded into internal hash tables where is can be used.
*/
static void loadAnalysis(Parse *pParse, int iDb){
................................................................................
  HashElem *k;
  int iStatCur;
  int iMem;

  sqlite3BeginWriteOperation(pParse, 0, iDb);
  iStatCur = pParse->nTab;
  pParse->nTab += 2;
  openStatTable(pParse, iDb, iStatCur, 0, 0);
  iMem = pParse->nMem+1;
  for(k=sqliteHashFirst(&pSchema->tblHash); k; k=sqliteHashNext(k)){
    Table *pTab = (Table*)sqliteHashData(k);
    analyzeOneTable(pParse, pTab, 0, iStatCur, iMem);
  }
  loadAnalysis(pParse, iDb);
}

/*
** Generate code that will do an analysis of a single table in
** a database.  If pOnlyIdx is not NULL then it is a single index
** in pTab that should be analyzed.
*/
static void analyzeTable(Parse *pParse, Table *pTab, Index *pOnlyIdx){
  int iDb;
  int iStatCur;

  assert( pTab!=0 );
  assert( sqlite3BtreeHoldsAllMutexes(pParse->db) );
  iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema);
  sqlite3BeginWriteOperation(pParse, 0, iDb);
  iStatCur = pParse->nTab;
  pParse->nTab += 2;
  if( pOnlyIdx ){
    openStatTable(pParse, iDb, iStatCur, pOnlyIdx->zName, "idx");
  }else{
    openStatTable(pParse, iDb, iStatCur, pTab->zName, "tbl");
  }
  analyzeOneTable(pParse, pTab, pOnlyIdx, iStatCur, pParse->nMem+1);
  loadAnalysis(pParse, iDb);
}

/*
** Generate code for the ANALYZE command.  The parser calls this routine
** when it recognizes an ANALYZE command.
**
................................................................................
*/
void sqlite3Analyze(Parse *pParse, Token *pName1, Token *pName2){
  sqlite3 *db = pParse->db;
  int iDb;
  int i;
  char *z, *zDb;
  Table *pTab;
  Index *pIdx;
  Token *pTableName;

  /* Read the database schema. If an error occurs, leave an error message
  ** and code in pParse and return NULL. */
  assert( sqlite3BtreeHoldsAllMutexes(pParse->db) );
  if( SQLITE_OK!=sqlite3ReadSchema(pParse) ){
    return;
................................................................................
    /* Form 2:  Analyze the database or table named */
    iDb = sqlite3FindDb(db, pName1);
    if( iDb>=0 ){
      analyzeDatabase(pParse, iDb);
    }else{
      z = sqlite3NameFromToken(db, pName1);
      if( z ){
        if( (pIdx = sqlite3FindIndex(db, z, 0))!=0 ){
          analyzeTable(pParse, pIdx->pTable, pIdx);
        }else if( (pTab = sqlite3LocateTable(pParse, 0, z, 0))!=0 ){


          analyzeTable(pParse, pTab, 0);
        }
        sqlite3DbFree(db, z);
      }
    }
  }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 ){
        if( (pIdx = sqlite3FindIndex(db, z, zDb))!=0 ){
          analyzeTable(pParse, pIdx->pTable, pIdx);
        }else if( (pTab = sqlite3LocateTable(pParse, 0, z, zDb))!=0 ){


          analyzeTable(pParse, pTab, 0);
        }
        sqlite3DbFree(db, z);
      }
    }   
  }
}

/*
** Used to pass information from the analyzer reader through to the

** SQLITE_IOERR
** 
** Errors during initialization of locks, or file system support for locks,
** should handle ENOLCK, ENOTSUP, EOPNOTSUPP separately.
*/
static int sqliteErrorFromPosixError(int posixError, int sqliteIOErr) {
  switch (posixError) {












  case 0: 
    return SQLITE_OK;

    
  case EAGAIN:
  case ETIMEDOUT:
  case EBUSY:
  case EINTR:
  case ENOLCK:  
    /* random NFS retry error, unless during file system support 
     * introspection, in which it actually means what it says */
................................................................................
	(sqliteIOErr == SQLITE_IOERR_CHECKRESERVEDLOCK) ){
      return SQLITE_BUSY;
    }
    /* else fall through */
  case EPERM: 
    return SQLITE_PERM;
    






  case EDEADLK:
    return SQLITE_IOERR_BLOCKED;

    
#if EOPNOTSUPP!=ENOTSUP
  case EOPNOTSUPP: 
    /* something went terribly awry, unless during file system support 
     * introspection, in which it actually means what it says */
#endif
#ifdef ENOTSUP
................................................................................
**
** The mutex entered using the unixEnterMutex() function must be held
** when this function is called.
*/
static void releaseInodeInfo(unixFile *pFile){
  unixInodeInfo *pInode = pFile->pInode;
  assert( unixMutexHeld() );
  if( pInode ){
    pInode->nRef--;
    if( pInode->nRef==0 ){
      assert( pInode->pShmNode==0 );
      closePendingFds(pFile);
      if( pInode->pPrev ){
        assert( pInode->pPrev->pNext==pInode );
        pInode->pPrev->pNext = pInode->pNext;
................................................................................
#ifndef __DJGPP__
  if( !reserved && !pFile->pInode->bProcessLock ){
    struct flock lock;
    lock.l_whence = SEEK_SET;
    lock.l_start = RESERVED_BYTE;
    lock.l_len = 1;
    lock.l_type = F_WRLCK;
    if (-1 == osFcntl(pFile->h, F_GETLK, &lock)) {
      int tErrno = errno;
      rc = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_CHECKRESERVEDLOCK);
      pFile->lastErrno = tErrno;
    } else if( lock.l_type!=F_UNLCK ){
      reserved = 1;
    }
  }
#endif
  
  unixLeaveMutex();
................................................................................
** in order to coordinate access between separate database connections
** within this process, but all of that is handled in memory and the
** operating system does not participate.
**
** This function is a pass-through to fcntl(F_SETLK) if pFile is using
** any VFS other than "unix-excl" or if pFile is opened on "unix-excl"
** and is read-only.



*/
static int unixFileLock(unixFile *pFile, struct flock *pLock){
  int rc;
  unixInodeInfo *pInode = pFile->pInode;
  assert( unixMutexHeld() );
  assert( pInode!=0 );
  if( ((pFile->ctrlFlags & UNIXFILE_EXCL)!=0 || pInode->bProcessLock)
................................................................................
  ** locking a random byte from a range, concurrent SHARED locks may exist
  ** even if the locking primitive used is always a write-lock.
  */
  int rc = SQLITE_OK;
  unixFile *pFile = (unixFile*)id;
  unixInodeInfo *pInode = pFile->pInode;
  struct flock lock;
  int s = 0;
  int tErrno = 0;

  assert( pFile );
  OSTRACE(("LOCK    %d %s was %s(%s,%d) pid=%d (unix)\n", pFile->h,
      azFileLock(eFileLock), azFileLock(pFile->eFileLock),
      azFileLock(pInode->eFileLock), pInode->nShared , getpid()));

................................................................................
  lock.l_len = 1L;
  lock.l_whence = SEEK_SET;
  if( eFileLock==SHARED_LOCK 
      || (eFileLock==EXCLUSIVE_LOCK && pFile->eFileLock<PENDING_LOCK)
  ){
    lock.l_type = (eFileLock==SHARED_LOCK?F_RDLCK:F_WRLCK);
    lock.l_start = PENDING_BYTE;
    s = unixFileLock(pFile, &lock);
    if( s==(-1) ){
      tErrno = errno;
      rc = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_LOCK);
      if( IS_LOCK_ERROR(rc) ){

        pFile->lastErrno = tErrno;
      }
      goto end_lock;
    }
  }


  /* If control gets to this point, then actually go ahead and make
  ** operating system calls for the specified lock.
  */
  if( eFileLock==SHARED_LOCK ){
    assert( pInode->nShared==0 );
    assert( pInode->eFileLock==0 );


    /* Now get the read-lock */
    lock.l_start = SHARED_FIRST;
    lock.l_len = SHARED_SIZE;
    if( (s = unixFileLock(pFile, &lock))==(-1) ){
      tErrno = errno;

    }

    /* Drop the temporary PENDING lock */
    lock.l_start = PENDING_BYTE;
    lock.l_len = 1L;
    lock.l_type = F_UNLCK;
    if( unixFileLock(pFile, &lock)!=0 ){
      if( s != -1 ){
        /* This could happen with a network mount */
        tErrno = errno; 
        rc = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_UNLOCK); 
        if( IS_LOCK_ERROR(rc) ){
          pFile->lastErrno = tErrno;
        }
        goto end_lock;
      }
    }
    if( s==(-1) ){
      rc = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_LOCK);
      if( IS_LOCK_ERROR(rc) ){

        pFile->lastErrno = tErrno;
      }

    }else{
      pFile->eFileLock = SHARED_LOCK;
      pInode->nLock++;
      pInode->nShared = 1;
    }
  }else if( eFileLock==EXCLUSIVE_LOCK && pInode->nShared>1 ){
    /* We are trying for an exclusive lock but another thread in this
................................................................................
  }else{
    /* The request was for a RESERVED or EXCLUSIVE lock.  It is
    ** assumed that there is a SHARED or greater lock on the file
    ** already.
    */
    assert( 0!=pFile->eFileLock );
    lock.l_type = F_WRLCK;
    switch( eFileLock ){


      case RESERVED_LOCK:
        lock.l_start = RESERVED_BYTE;
        break;
      case EXCLUSIVE_LOCK:

        lock.l_start = SHARED_FIRST;
        lock.l_len = SHARED_SIZE;
        break;
      default:
        assert(0);
    }

    s = unixFileLock(pFile, &lock);
    if( s==(-1) ){
      tErrno = errno;
      rc = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_LOCK);
      if( IS_LOCK_ERROR(rc) ){

        pFile->lastErrno = tErrno;
      }
    }
  }
  

#ifndef NDEBUG
................................................................................
*/
static int posixUnlock(sqlite3_file *id, int eFileLock, int handleNFSUnlock){
  unixFile *pFile = (unixFile*)id;
  unixInodeInfo *pInode;
  struct flock lock;
  int rc = SQLITE_OK;
  int h;
  int tErrno;                      /* Error code from system call errors */

  assert( pFile );
  OSTRACE(("UNLOCK  %d %d was %d(%d,%d) pid=%d (unix)\n", pFile->h, eFileLock,
      pFile->eFileLock, pFile->pInode->eFileLock, pFile->pInode->nShared,
      getpid()));

  assert( eFileLock<=SHARED_LOCK );
................................................................................

#if !defined(__APPLE__) || !SQLITE_ENABLE_LOCKING_STYLE
      (void)handleNFSUnlock;
      assert( handleNFSUnlock==0 );
#endif
#if defined(__APPLE__) && SQLITE_ENABLE_LOCKING_STYLE
      if( handleNFSUnlock ){

        off_t divSize = SHARED_SIZE - 1;
        
        lock.l_type = F_UNLCK;
        lock.l_whence = SEEK_SET;
        lock.l_start = SHARED_FIRST;
        lock.l_len = divSize;
        if( unixFileLock(pFile,, &lock)==(-1) ){
          tErrno = errno;
          rc = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_UNLOCK);
          if( IS_LOCK_ERROR(rc) ){
            pFile->lastErrno = tErrno;
          }
          goto end_unlock;
        }
        lock.l_type = F_RDLCK;
        lock.l_whence = SEEK_SET;
................................................................................
        }
        lock.l_type = F_UNLCK;
        lock.l_whence = SEEK_SET;
        lock.l_start = SHARED_FIRST+divSize;
        lock.l_len = SHARED_SIZE-divSize;
        if( unixFileLock(pFile, &lock)==(-1) ){
          tErrno = errno;
          rc = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_UNLOCK);
          if( IS_LOCK_ERROR(rc) ){
            pFile->lastErrno = tErrno;
          }
          goto end_unlock;
        }
      }else
#endif /* defined(__APPLE__) && SQLITE_ENABLE_LOCKING_STYLE */
      {
        lock.l_type = F_RDLCK;
        lock.l_whence = SEEK_SET;
        lock.l_start = SHARED_FIRST;
        lock.l_len = SHARED_SIZE;
        if( unixFileLock(pFile, &lock)==(-1) ){
          tErrno = errno;





          rc = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_RDLOCK);
          if( IS_LOCK_ERROR(rc) ){
            pFile->lastErrno = tErrno;
          }
          goto end_unlock;
        }
      }
    }
    lock.l_type = F_UNLCK;
    lock.l_whence = SEEK_SET;
    lock.l_start = PENDING_BYTE;
    lock.l_len = 2L;  assert( PENDING_BYTE+1==RESERVED_BYTE );
    if( unixFileLock(pFile, &lock)!=(-1) ){
      pInode->eFileLock = SHARED_LOCK;
    }else{
      tErrno = errno;
      rc = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_UNLOCK);
      if( IS_LOCK_ERROR(rc) ){
        pFile->lastErrno = tErrno;
      }
      goto end_unlock;
    }
  }
  if( eFileLock==NO_LOCK ){
    /* Decrement the shared lock counter.  Release the lock using an
    ** OS call only when all threads in this same process have released
    ** the lock.
................................................................................
    if( pInode->nShared==0 ){
      lock.l_type = F_UNLCK;
      lock.l_whence = SEEK_SET;
      lock.l_start = lock.l_len = 0L;
      SimulateIOErrorBenign(1);
      SimulateIOError( h=(-1) )
      SimulateIOErrorBenign(0);
      if( unixFileLock(pFile, &lock)!=(-1) ){
        pInode->eFileLock = NO_LOCK;
      }else{
        tErrno = errno;
        rc = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_UNLOCK);
        if( IS_LOCK_ERROR(rc) ){
          pFile->lastErrno = tErrno;
        }
        pInode->eFileLock = NO_LOCK;
        pFile->eFileLock = NO_LOCK;
      }
    }

    /* Decrement the count of locks against this same file.  When the
    ** count reaches zero, close any other file descriptors whose close
................................................................................
**
** It is *not* necessary to hold the mutex when this routine is called,
** even on VxWorks.  A mutex will be acquired on VxWorks by the
** vxworksReleaseFileId() routine.
*/
static int closeUnixFile(sqlite3_file *id){
  unixFile *pFile = (unixFile*)id;
  if( pFile ){
    if( pFile->dirfd>=0 ){
      robust_close(pFile, pFile->dirfd, __LINE__);
      pFile->dirfd=-1;
    }
    if( pFile->h>=0 ){
      robust_close(pFile, pFile->h, __LINE__);
      pFile->h = -1;
    }
#if OS_VXWORKS
    if( pFile->pId ){
      if( pFile->isDelete ){
        unlink(pFile->pId->zCanonicalName);
      }
      vxworksReleaseFileId(pFile->pId);
      pFile->pId = 0;
    }
#endif
    OSTRACE(("CLOSE   %-3d\n", pFile->h));
    OpenCounter(-1);
    sqlite3_free(pFile->pUnused);
    memset(pFile, 0, sizeof(unixFile));
  }
  return SQLITE_OK;
}

/*
** Close a file.
*/
static int unixClose(sqlite3_file *id){
  int rc = SQLITE_OK;
  if( id ){
    unixFile *pFile = (unixFile *)id;
    unixUnlock(id, NO_LOCK);
    unixEnterMutex();

    assert( pFile->pInode==0 || pFile->pInode->nLock>0


            || pFile->pInode->bProcessLock==0 );
    if( pFile->pInode && pFile->pInode->nLock ){
      /* If there are outstanding locks, do not actually close the file just
      ** yet because that would clear those locks.  Instead, add the file
      ** descriptor to pInode->pUnused list.  It will be automatically closed 
      ** when the last lock is cleared.
      */
      setPendingFd(pFile);
    }
    releaseInodeInfo(pFile);
    rc = closeUnixFile(id);
    unixLeaveMutex();
  }
  return rc;
}

/************** End of the posix advisory lock implementation *****************
******************************************************************************/

/******************************************************************************
................................................................................
  
  /* To fully unlock the database, delete the lock file */
  assert( eFileLock==NO_LOCK );
  if( unlink(zLockFile) ){
    int rc = 0;
    int tErrno = errno;
    if( ENOENT != tErrno ){
      rc = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_UNLOCK);
    }
    if( IS_LOCK_ERROR(rc) ){
      pFile->lastErrno = tErrno;
    }
    return rc; 
  }
  pFile->eFileLock = NO_LOCK;
................................................................................
    int lrc = robust_flock(pFile->h, LOCK_EX | LOCK_NB);
    if( !lrc ){
      /* got the lock, unlock it */
      lrc = robust_flock(pFile->h, LOCK_UN);
      if ( lrc ) {
        int tErrno = errno;
        /* unlock failed with an error */
        lrc = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_UNLOCK); 
        if( IS_LOCK_ERROR(lrc) ){
          pFile->lastErrno = tErrno;
          rc = lrc;
        }
      }
    } else {
      int tErrno = errno;
................................................................................
  /* shared can just be set because we always have an exclusive */
  if (eFileLock==SHARED_LOCK) {
    pFile->eFileLock = eFileLock;
    return SQLITE_OK;
  }
  
  /* no, really, unlock. */
  int rc = robust_flock(pFile->h, LOCK_UN);
  if (rc) {
    int r, tErrno = errno;
    r = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_UNLOCK);
    if( IS_LOCK_ERROR(r) ){
      pFile->lastErrno = tErrno;
    }
#ifdef SQLITE_IGNORE_FLOCK_LOCK_ERRORS
    if( (r & SQLITE_IOERR) == SQLITE_IOERR ){
      r = SQLITE_BUSY;
    }
#endif /* SQLITE_IGNORE_FLOCK_LOCK_ERRORS */
    
    return r;
  } else {
    pFile->eFileLock = NO_LOCK;
    return SQLITE_OK;
  }
}

/*
** Close a file.
................................................................................
  TIMER_START;
#if defined(USE_PREAD)
  do{ got = osPwrite(id->h, pBuf, cnt, offset); }while( got<0 && errno==EINTR );
#elif defined(USE_PREAD64)
  do{ got = osPwrite64(id->h, pBuf, cnt, offset);}while( got<0 && errno==EINTR);
#else
  newOffset = lseek(id->h, offset, SEEK_SET);

  if( newOffset!=offset ){
    if( newOffset == -1 ){
      ((unixFile*)id)->lastErrno = errno;
    }else{
      ((unixFile*)id)->lastErrno = 0;			
    }
    return -1;
................................................................................
    i64 nSize;                    /* Required file size */
    struct stat buf;              /* Used to hold return values of fstat() */
   
    if( osFstat(pFile->h, &buf) ) return SQLITE_IOERR_FSTAT;

    nSize = ((nByte+pFile->szChunk-1) / pFile->szChunk) * pFile->szChunk;
    if( nSize>(i64)buf.st_size ){

#if defined(HAVE_POSIX_FALLOCATE) && HAVE_POSIX_FALLOCATE



      int rc;
      do{
        rc = osFallocate(pFile->h, buf.st_size, nSize-buf.st_size);
      }while( rc<0 && errno==EINTR );
      if( rc ) return SQLITE_IOERR_WRITE;
#else
      /* If the OS does not have posix_fallocate(), fake it. First use
      ** ftruncate() to set the file size, then write a single byte to
      ** the last byte in each block within the extended region. This
      ** is the same technique used by glibc to implement posix_fallocate()
      ** on systems that do not have a real fallocate() system call.
      */
................................................................................
  pNew = (unixFile *)sqlite3_malloc(sizeof(*pNew));
  if( pNew==NULL ){
    rc = SQLITE_NOMEM;
    goto end_create_proxy;
  }
  memset(pNew, 0, sizeof(unixFile));
  pNew->openFlags = openFlags;

  dummyVfs.pAppData = (void*)&autolockIoFinder;

  pUnused->fd = fd;
  pUnused->flags = openFlags;
  pNew->pUnused = pUnused;
  
  rc = fillInUnixFile(&dummyVfs, fd, dirfd, (sqlite3_file*)pNew, path, 0, 0, 0);
  if( rc==SQLITE_OK ){
    *ppFile = pNew;

** SQLITE_IOERR
** 
** Errors during initialization of locks, or file system support for locks,
** should handle ENOLCK, ENOTSUP, EOPNOTSUPP separately.
*/
static int sqliteErrorFromPosixError(int posixError, int sqliteIOErr) {
  switch (posixError) {
#if 0
  /* At one point this code was not commented out. In theory, this branch
  ** should never be hit, as this function should only be called after
  ** a locking-related function (i.e. fcntl()) has returned non-zero with
  ** the value of errno as the first argument. Since a system call has failed,
  ** errno should be non-zero.
  **
  ** Despite this, if errno really is zero, we still don't want to return
  ** SQLITE_OK. The system call failed, and *some* SQLite error should be
  ** propagated back to the caller. Commenting this branch out means errno==0
  ** will be handled by the "default:" case below.
  */
  case 0: 
    return SQLITE_OK;
#endif

  case EAGAIN:
  case ETIMEDOUT:
  case EBUSY:
  case EINTR:
  case ENOLCK:  
    /* random NFS retry error, unless during file system support 
     * introspection, in which it actually means what it says */
................................................................................
	(sqliteIOErr == SQLITE_IOERR_CHECKRESERVEDLOCK) ){
      return SQLITE_BUSY;
    }
    /* else fall through */
  case EPERM: 
    return SQLITE_PERM;
    
  /* EDEADLK is only possible if a call to fcntl(F_SETLKW) is made. And
  ** this module never makes such a call. And the code in SQLite itself 
  ** asserts that SQLITE_IOERR_BLOCKED is never returned. For these reasons
  ** this case is also commented out. If the system does set errno to EDEADLK,
  ** the default SQLITE_IOERR_XXX code will be returned. */
#if 0
  case EDEADLK:
    return SQLITE_IOERR_BLOCKED;
#endif
    
#if EOPNOTSUPP!=ENOTSUP
  case EOPNOTSUPP: 
    /* something went terribly awry, unless during file system support 
     * introspection, in which it actually means what it says */
#endif
#ifdef ENOTSUP
................................................................................
**
** The mutex entered using the unixEnterMutex() function must be held
** when this function is called.
*/
static void releaseInodeInfo(unixFile *pFile){
  unixInodeInfo *pInode = pFile->pInode;
  assert( unixMutexHeld() );
  if( ALWAYS(pInode) ){
    pInode->nRef--;
    if( pInode->nRef==0 ){
      assert( pInode->pShmNode==0 );
      closePendingFds(pFile);
      if( pInode->pPrev ){
        assert( pInode->pPrev->pNext==pInode );
        pInode->pPrev->pNext = pInode->pNext;
................................................................................
#ifndef __DJGPP__
  if( !reserved && !pFile->pInode->bProcessLock ){
    struct flock lock;
    lock.l_whence = SEEK_SET;
    lock.l_start = RESERVED_BYTE;
    lock.l_len = 1;
    lock.l_type = F_WRLCK;
    if( osFcntl(pFile->h, F_GETLK, &lock) ){

      rc = SQLITE_IOERR_CHECKRESERVEDLOCK;
      pFile->lastErrno = errno;
    } else if( lock.l_type!=F_UNLCK ){
      reserved = 1;
    }
  }
#endif
  
  unixLeaveMutex();
................................................................................
** in order to coordinate access between separate database connections
** within this process, but all of that is handled in memory and the
** operating system does not participate.
**
** This function is a pass-through to fcntl(F_SETLK) if pFile is using
** any VFS other than "unix-excl" or if pFile is opened on "unix-excl"
** and is read-only.
**
** Zero is returned if the call completes successfully, or -1 if a call
** to fcntl() fails. In this case, errno is set appropriately (by fcntl()).
*/
static int unixFileLock(unixFile *pFile, struct flock *pLock){
  int rc;
  unixInodeInfo *pInode = pFile->pInode;
  assert( unixMutexHeld() );
  assert( pInode!=0 );
  if( ((pFile->ctrlFlags & UNIXFILE_EXCL)!=0 || pInode->bProcessLock)
................................................................................
  ** locking a random byte from a range, concurrent SHARED locks may exist
  ** even if the locking primitive used is always a write-lock.
  */
  int rc = SQLITE_OK;
  unixFile *pFile = (unixFile*)id;
  unixInodeInfo *pInode = pFile->pInode;
  struct flock lock;

  int tErrno = 0;

  assert( pFile );
  OSTRACE(("LOCK    %d %s was %s(%s,%d) pid=%d (unix)\n", pFile->h,
      azFileLock(eFileLock), azFileLock(pFile->eFileLock),
      azFileLock(pInode->eFileLock), pInode->nShared , getpid()));

................................................................................
  lock.l_len = 1L;
  lock.l_whence = SEEK_SET;
  if( eFileLock==SHARED_LOCK 
      || (eFileLock==EXCLUSIVE_LOCK && pFile->eFileLock<PENDING_LOCK)
  ){
    lock.l_type = (eFileLock==SHARED_LOCK?F_RDLCK:F_WRLCK);
    lock.l_start = PENDING_BYTE;
    if( unixFileLock(pFile, &lock) ){

      tErrno = errno;
      rc = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_LOCK);

      if( rc!=SQLITE_BUSY ){
        pFile->lastErrno = tErrno;
      }
      goto end_lock;
    }
  }


  /* If control gets to this point, then actually go ahead and make
  ** operating system calls for the specified lock.
  */
  if( eFileLock==SHARED_LOCK ){
    assert( pInode->nShared==0 );
    assert( pInode->eFileLock==0 );
    assert( rc==SQLITE_OK );

    /* Now get the read-lock */
    lock.l_start = SHARED_FIRST;
    lock.l_len = SHARED_SIZE;
    if( unixFileLock(pFile, &lock) ){
      tErrno = errno;
      rc = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_LOCK);
    }

    /* Drop the temporary PENDING lock */
    lock.l_start = PENDING_BYTE;
    lock.l_len = 1L;
    lock.l_type = F_UNLCK;
    if( unixFileLock(pFile, &lock) && rc==SQLITE_OK ){

      /* This could happen with a network mount */
      tErrno = errno;
      rc = SQLITE_IOERR_UNLOCK; 


    }



    if( rc ){


      if( rc!=SQLITE_BUSY ){
        pFile->lastErrno = tErrno;
      }
      goto end_lock;
    }else{
      pFile->eFileLock = SHARED_LOCK;
      pInode->nLock++;
      pInode->nShared = 1;
    }
  }else if( eFileLock==EXCLUSIVE_LOCK && pInode->nShared>1 ){
    /* We are trying for an exclusive lock but another thread in this
................................................................................
  }else{
    /* The request was for a RESERVED or EXCLUSIVE lock.  It is
    ** assumed that there is a SHARED or greater lock on the file
    ** already.
    */
    assert( 0!=pFile->eFileLock );
    lock.l_type = F_WRLCK;


    assert( eFileLock==RESERVED_LOCK || eFileLock==EXCLUSIVE_LOCK );
    if( eFileLock==RESERVED_LOCK ){
      lock.l_start = RESERVED_BYTE;

      lock.l_len = 1L;
    }else{
      lock.l_start = SHARED_FIRST;
      lock.l_len = SHARED_SIZE;



    }

    if( unixFileLock(pFile, &lock) ){

      tErrno = errno;
      rc = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_LOCK);

      if( rc!=SQLITE_BUSY ){
        pFile->lastErrno = tErrno;
      }
    }
  }
  

#ifndef NDEBUG
................................................................................
*/
static int posixUnlock(sqlite3_file *id, int eFileLock, int handleNFSUnlock){
  unixFile *pFile = (unixFile*)id;
  unixInodeInfo *pInode;
  struct flock lock;
  int rc = SQLITE_OK;
  int h;


  assert( pFile );
  OSTRACE(("UNLOCK  %d %d was %d(%d,%d) pid=%d (unix)\n", pFile->h, eFileLock,
      pFile->eFileLock, pFile->pInode->eFileLock, pFile->pInode->nShared,
      getpid()));

  assert( eFileLock<=SHARED_LOCK );
................................................................................

#if !defined(__APPLE__) || !SQLITE_ENABLE_LOCKING_STYLE
      (void)handleNFSUnlock;
      assert( handleNFSUnlock==0 );
#endif
#if defined(__APPLE__) && SQLITE_ENABLE_LOCKING_STYLE
      if( handleNFSUnlock ){
        int tErrno;               /* Error code from system call errors */
        off_t divSize = SHARED_SIZE - 1;
        
        lock.l_type = F_UNLCK;
        lock.l_whence = SEEK_SET;
        lock.l_start = SHARED_FIRST;
        lock.l_len = divSize;
        if( unixFileLock(pFile, &lock)==(-1) ){
          tErrno = errno;
          rc = SQLITE_IOERR_UNLOCK;
          if( IS_LOCK_ERROR(rc) ){
            pFile->lastErrno = tErrno;
          }
          goto end_unlock;
        }
        lock.l_type = F_RDLCK;
        lock.l_whence = SEEK_SET;
................................................................................
        }
        lock.l_type = F_UNLCK;
        lock.l_whence = SEEK_SET;
        lock.l_start = SHARED_FIRST+divSize;
        lock.l_len = SHARED_SIZE-divSize;
        if( unixFileLock(pFile, &lock)==(-1) ){
          tErrno = errno;
          rc = SQLITE_IOERR_UNLOCK;
          if( IS_LOCK_ERROR(rc) ){
            pFile->lastErrno = tErrno;
          }
          goto end_unlock;
        }
      }else
#endif /* defined(__APPLE__) && SQLITE_ENABLE_LOCKING_STYLE */
      {
        lock.l_type = F_RDLCK;
        lock.l_whence = SEEK_SET;
        lock.l_start = SHARED_FIRST;
        lock.l_len = SHARED_SIZE;
        if( unixFileLock(pFile, &lock) ){
          /* In theory, the call to unixFileLock() cannot fail because another
          ** process is holding an incompatible lock. If it does, this 
          ** indicates that the other process is not following the locking
          ** protocol. If this happens, return SQLITE_IOERR_RDLOCK. Returning
          ** SQLITE_BUSY would confuse the upper layer (in practice it causes 
          ** an assert to fail). */ 
          rc = SQLITE_IOERR_RDLOCK;

          pFile->lastErrno = errno;

          goto end_unlock;
        }
      }
    }
    lock.l_type = F_UNLCK;
    lock.l_whence = SEEK_SET;
    lock.l_start = PENDING_BYTE;
    lock.l_len = 2L;  assert( PENDING_BYTE+1==RESERVED_BYTE );
    if( unixFileLock(pFile, &lock)==0 ){
      pInode->eFileLock = SHARED_LOCK;
    }else{

      rc = SQLITE_IOERR_UNLOCK;

      pFile->lastErrno = errno;

      goto end_unlock;
    }
  }
  if( eFileLock==NO_LOCK ){
    /* Decrement the shared lock counter.  Release the lock using an
    ** OS call only when all threads in this same process have released
    ** the lock.
................................................................................
    if( pInode->nShared==0 ){
      lock.l_type = F_UNLCK;
      lock.l_whence = SEEK_SET;
      lock.l_start = lock.l_len = 0L;
      SimulateIOErrorBenign(1);
      SimulateIOError( h=(-1) )
      SimulateIOErrorBenign(0);
      if( unixFileLock(pFile, &lock)==0 ){
        pInode->eFileLock = NO_LOCK;
      }else{

        rc = SQLITE_IOERR_UNLOCK;

	pFile->lastErrno = errno;

        pInode->eFileLock = NO_LOCK;
        pFile->eFileLock = NO_LOCK;
      }
    }

    /* Decrement the count of locks against this same file.  When the
    ** count reaches zero, close any other file descriptors whose close
................................................................................
**
** It is *not* necessary to hold the mutex when this routine is called,
** even on VxWorks.  A mutex will be acquired on VxWorks by the
** vxworksReleaseFileId() routine.
*/
static int closeUnixFile(sqlite3_file *id){
  unixFile *pFile = (unixFile*)id;

  if( pFile->dirfd>=0 ){
    robust_close(pFile, pFile->dirfd, __LINE__);
    pFile->dirfd=-1;
  }
  if( pFile->h>=0 ){
    robust_close(pFile, pFile->h, __LINE__);
    pFile->h = -1;
  }
#if OS_VXWORKS
  if( pFile->pId ){
    if( pFile->isDelete ){
      unlink(pFile->pId->zCanonicalName);
    }
    vxworksReleaseFileId(pFile->pId);
    pFile->pId = 0;
  }
#endif
  OSTRACE(("CLOSE   %-3d\n", pFile->h));
  OpenCounter(-1);
  sqlite3_free(pFile->pUnused);
  memset(pFile, 0, sizeof(unixFile));

  return SQLITE_OK;
}

/*
** Close a file.
*/
static int unixClose(sqlite3_file *id){
  int rc = SQLITE_OK;

  unixFile *pFile = (unixFile *)id;
  unixUnlock(id, NO_LOCK);
  unixEnterMutex();

  /* unixFile.pInode is always valid here. Otherwise, a different close
  ** routine (e.g. nolockClose()) would be called instead.
  */
  assert( pFile->pInode->nLock>0 || pFile->pInode->bProcessLock==0 );
  if( ALWAYS(pFile->pInode) && pFile->pInode->nLock ){
    /* If there are outstanding locks, do not actually close the file just
    ** yet because that would clear those locks.  Instead, add the file
    ** descriptor to pInode->pUnused list.  It will be automatically closed 
    ** when the last lock is cleared.
    */
    setPendingFd(pFile);
  }
  releaseInodeInfo(pFile);
  rc = closeUnixFile(id);
  unixLeaveMutex();

  return rc;
}

/************** End of the posix advisory lock implementation *****************
******************************************************************************/

/******************************************************************************
................................................................................
  
  /* To fully unlock the database, delete the lock file */
  assert( eFileLock==NO_LOCK );
  if( unlink(zLockFile) ){
    int rc = 0;
    int tErrno = errno;
    if( ENOENT != tErrno ){
      rc = SQLITE_IOERR_UNLOCK;
    }
    if( IS_LOCK_ERROR(rc) ){
      pFile->lastErrno = tErrno;
    }
    return rc; 
  }
  pFile->eFileLock = NO_LOCK;
................................................................................
    int lrc = robust_flock(pFile->h, LOCK_EX | LOCK_NB);
    if( !lrc ){
      /* got the lock, unlock it */
      lrc = robust_flock(pFile->h, LOCK_UN);
      if ( lrc ) {
        int tErrno = errno;
        /* unlock failed with an error */
        lrc = SQLITE_IOERR_UNLOCK; 
        if( IS_LOCK_ERROR(lrc) ){
          pFile->lastErrno = tErrno;
          rc = lrc;
        }
      }
    } else {
      int tErrno = errno;
................................................................................
  /* shared can just be set because we always have an exclusive */
  if (eFileLock==SHARED_LOCK) {
    pFile->eFileLock = eFileLock;
    return SQLITE_OK;
  }
  
  /* no, really, unlock. */
  if( robust_flock(pFile->h, LOCK_UN) ){






#ifdef SQLITE_IGNORE_FLOCK_LOCK_ERRORS

    return SQLITE_OK;

#endif /* SQLITE_IGNORE_FLOCK_LOCK_ERRORS */

    return SQLITE_IOERR_UNLOCK;
  }else{
    pFile->eFileLock = NO_LOCK;
    return SQLITE_OK;
  }
}

/*
** Close a file.
................................................................................
  TIMER_START;
#if defined(USE_PREAD)
  do{ got = osPwrite(id->h, pBuf, cnt, offset); }while( got<0 && errno==EINTR );
#elif defined(USE_PREAD64)
  do{ got = osPwrite64(id->h, pBuf, cnt, offset);}while( got<0 && errno==EINTR);
#else
  newOffset = lseek(id->h, offset, SEEK_SET);
  SimulateIOError( newOffset-- );
  if( newOffset!=offset ){
    if( newOffset == -1 ){
      ((unixFile*)id)->lastErrno = errno;
    }else{
      ((unixFile*)id)->lastErrno = 0;			
    }
    return -1;
................................................................................
    i64 nSize;                    /* Required file size */
    struct stat buf;              /* Used to hold return values of fstat() */
   
    if( osFstat(pFile->h, &buf) ) return SQLITE_IOERR_FSTAT;

    nSize = ((nByte+pFile->szChunk-1) / pFile->szChunk) * pFile->szChunk;
    if( nSize>(i64)buf.st_size ){

#if defined(HAVE_POSIX_FALLOCATE) && HAVE_POSIX_FALLOCATE
      /* The code below is handling the return value of osFallocate() 
      ** correctly. posix_fallocate() is defined to "returns zero on success, 
      ** or an error number on  failure". See the manpage for details. */
      int err;
      do{
        err = osFallocate(pFile->h, buf.st_size, nSize-buf.st_size);
      }while( err==EINTR );
      if( err ) return SQLITE_IOERR_WRITE;
#else
      /* If the OS does not have posix_fallocate(), fake it. First use
      ** ftruncate() to set the file size, then write a single byte to
      ** the last byte in each block within the extended region. This
      ** is the same technique used by glibc to implement posix_fallocate()
      ** on systems that do not have a real fallocate() system call.
      */
................................................................................
  pNew = (unixFile *)sqlite3_malloc(sizeof(*pNew));
  if( pNew==NULL ){
    rc = SQLITE_NOMEM;
    goto end_create_proxy;
  }
  memset(pNew, 0, sizeof(unixFile));
  pNew->openFlags = openFlags;
  memset(&dummyVfs, 0, sizeof(dummyVfs));
  dummyVfs.pAppData = (void*)&autolockIoFinder;
  dummyVfs.zName = "dummy";
  pUnused->fd = fd;
  pUnused->flags = openFlags;
  pNew->pUnused = pUnused;
  
  rc = fillInUnixFile(&dummyVfs, fd, dirfd, (sqlite3_file*)pNew, path, 0, 0, 0);
  if( rc==SQLITE_OK ){
    *ppFile = pNew;

  rc = sqlite3_file_control(db, zDb, SQLITE_FCNTL_CHUNK_SIZE, (void *)&nSize);
  if( rc ){
    Tcl_SetResult(interp, (char *)sqlite3TestErrorName(rc), TCL_STATIC);
    return TCL_ERROR;
  }
  return TCL_OK;
}







































/*
** tclcmd:   file_control_lockproxy_test DB PWD
**
** This TCL command runs the sqlite3_file_control interface and
** verifies correct operation of the SQLITE_GET_LOCKPROXYFILE and
** SQLITE_SET_LOCKPROXYFILE verbs.
................................................................................
     { "vfs_initfail_test",          vfs_initfail_test,   0   },
     { "vfs_unregister_all",         vfs_unregister_all,  0   },
     { "vfs_reregister_all",         vfs_reregister_all,  0   },
     { "file_control_test",          file_control_test,   0   },
     { "file_control_lasterrno_test", file_control_lasterrno_test,  0   },
     { "file_control_lockproxy_test", file_control_lockproxy_test,  0   },
     { "file_control_chunksize_test", file_control_chunksize_test,  0   },

     { "sqlite3_vfs_list",           vfs_list,     0   },
     { "sqlite3_create_function_v2", test_create_function_v2, 0 },

     /* Functions from os.h */
#ifndef SQLITE_OMIT_UTF16
     { "add_test_collate",        test_collate, 0            },
     { "add_test_collate_needed", test_collate_needed, 0     },

  rc = sqlite3_file_control(db, zDb, SQLITE_FCNTL_CHUNK_SIZE, (void *)&nSize);
  if( rc ){
    Tcl_SetResult(interp, (char *)sqlite3TestErrorName(rc), TCL_STATIC);
    return TCL_ERROR;
  }
  return TCL_OK;
}

/*
** tclcmd:   file_control_sizehint_test DB DBNAME SIZE
**
** This TCL command runs the sqlite3_file_control interface and
** verifies correct operation of the SQLITE_GET_LOCKPROXYFILE and
** SQLITE_SET_LOCKPROXYFILE verbs.
*/
static int file_control_sizehint_test(
  ClientData clientData, /* Pointer to sqlite3_enable_XXX function */
  Tcl_Interp *interp,    /* The TCL interpreter that invoked this command */
  int objc,              /* Number of arguments */
  Tcl_Obj *CONST objv[]  /* Command arguments */
){
  sqlite3_int64 nSize;            /* Hinted size */
  char *zDb;                      /* Db name ("main", "temp" etc.) */
  sqlite3 *db;                    /* Database handle */
  int rc;                         /* file_control() return code */

  if( objc!=4 ){
    Tcl_WrongNumArgs(interp, 1, objv, "DB DBNAME SIZE");
    return TCL_ERROR;
  }
  if( getDbPointer(interp, Tcl_GetString(objv[1]), &db) 
   || Tcl_GetWideIntFromObj(interp, objv[3], &nSize)
  ){
   return TCL_ERROR;
  }
  zDb = Tcl_GetString(objv[2]);
  if( zDb[0]=='\0' ) zDb = NULL;

  rc = sqlite3_file_control(db, zDb, SQLITE_FCNTL_SIZE_HINT, (void *)&nSize);
  if( rc ){
    Tcl_SetResult(interp, (char *)sqlite3TestErrorName(rc), TCL_STATIC);
    return TCL_ERROR;
  }
  return TCL_OK;
}

/*
** tclcmd:   file_control_lockproxy_test DB PWD
**
** This TCL command runs the sqlite3_file_control interface and
** verifies correct operation of the SQLITE_GET_LOCKPROXYFILE and
** SQLITE_SET_LOCKPROXYFILE verbs.
................................................................................
     { "vfs_initfail_test",          vfs_initfail_test,   0   },
     { "vfs_unregister_all",         vfs_unregister_all,  0   },
     { "vfs_reregister_all",         vfs_reregister_all,  0   },
     { "file_control_test",          file_control_test,   0   },
     { "file_control_lasterrno_test", file_control_lasterrno_test,  0   },
     { "file_control_lockproxy_test", file_control_lockproxy_test,  0   },
     { "file_control_chunksize_test", file_control_chunksize_test,  0   },
     { "file_control_sizehint_test", file_control_sizehint_test,  0   },
     { "sqlite3_vfs_list",           vfs_list,     0   },
     { "sqlite3_create_function_v2", test_create_function_v2, 0 },

     /* Functions from os.h */
#ifndef SQLITE_OMIT_UTF16
     { "add_test_collate",        test_collate, 0            },
     { "add_test_collate_needed", test_collate_needed, 0     },

  z = sqlite3_malloc( n+3 );
  n = sqlite3TestHexToBin(zOrig, n, z);
  z[n] = 0;
  nOut = sqlite3Utf8To8(z);
  sqlite3TestBinToHex(z,nOut);
  Tcl_AppendResult(interp, (char*)z, 0);
  sqlite3_free(z);

#endif



  return TCL_OK;

}

static int getFts3Varint(const char *p, sqlite_int64 *v){
  const unsigned char *q = (const unsigned char *) p;
  sqlite_uint64 x = 0, y = 1;
  while( (*q & 0x80) == 0x80 ){
    x += y * (*q++ & 0x7f);

  z = sqlite3_malloc( n+3 );
  n = sqlite3TestHexToBin(zOrig, n, z);
  z[n] = 0;
  nOut = sqlite3Utf8To8(z);
  sqlite3TestBinToHex(z,nOut);
  Tcl_AppendResult(interp, (char*)z, 0);
  sqlite3_free(z);
  return TCL_OK;
#else
  Tcl_AppendResult(interp, 
      "[utf8_to_utf8] unavailable - SQLITE_DEBUG not defined", 0
  );
  return TCL_ERROR;
#endif
}

static int getFts3Varint(const char *p, sqlite_int64 *v){
  const unsigned char *q = (const unsigned char *) p;
  sqlite_uint64 x = 0, y = 1;
  while( (*q & 0x80) == 0x80 ){
    x += y * (*q++ & 0x7f);

  /*  0 */ { "open",      (sqlite3_syscall_ptr)ts_open,      0, EACCES, 0 },
  /*  1 */ { "close",     (sqlite3_syscall_ptr)ts_close,     0, 0, 0 },
  /*  2 */ { "access",    (sqlite3_syscall_ptr)ts_access,    0, 0, 0 },
  /*  3 */ { "getcwd",    (sqlite3_syscall_ptr)ts_getcwd,    0, 0, 0 },
  /*  4 */ { "stat",      (sqlite3_syscall_ptr)ts_stat,      0, 0, 0 },
  /*  5 */ { "fstat",     (sqlite3_syscall_ptr)ts_fstat,     0, 0, 0 },
  /*  6 */ { "ftruncate", (sqlite3_syscall_ptr)ts_ftruncate, 0, EIO, 0 },
  /*  7 */ { "fcntl",     (sqlite3_syscall_ptr)ts_fcntl,     0, 0, 0 },
  /*  8 */ { "read",      (sqlite3_syscall_ptr)ts_read,      0, 0, 0 },
  /*  9 */ { "pread",     (sqlite3_syscall_ptr)ts_pread,     0, 0, 0 },
  /* 10 */ { "pread64",   (sqlite3_syscall_ptr)ts_pread64,   0, 0, 0 },
  /* 11 */ { "write",     (sqlite3_syscall_ptr)ts_write,     0, 0, 0 },
  /* 12 */ { "pwrite",    (sqlite3_syscall_ptr)ts_pwrite,    0, 0, 0 },
  /* 13 */ { "pwrite64",  (sqlite3_syscall_ptr)ts_pwrite64,  0, 0, 0 },
  /* 14 */ { "fchmod",    (sqlite3_syscall_ptr)ts_fchmod,    0, 0, 0 },
................................................................................

/*
** A wrapper around fcntl().
*/
static int ts_fcntl(int fd, int cmd, ... ){
  va_list ap;
  void *pArg;
  if( tsIsFail() ){
    return -1;
  }
  va_start(ap, cmd);
  pArg = va_arg(ap, void *);
  return orig_fcntl(fd, cmd, pArg);
}

/*
** A wrapper around read().
*/
static int ts_read(int fd, void *aBuf, size_t nBuf){
  if( tsIsFail() ){
    return -1;
  }
  return orig_read(fd, aBuf, nBuf);
}

/*
** A wrapper around pread().
*/
static int ts_pread(int fd, void *aBuf, size_t nBuf, off_t off){
  if( tsIsFail() ){
    return -1;
  }
  return orig_pread(fd, aBuf, nBuf, off);
}

/*
** A wrapper around pread64().
*/
static int ts_pread64(int fd, void *aBuf, size_t nBuf, off_t off){
  if( tsIsFail() ){
    return -1;
  }
  return orig_pread64(fd, aBuf, nBuf, off);
}

/*
** A wrapper around write().
*/
static int ts_write(int fd, const void *aBuf, size_t nBuf){
  if( tsIsFail() ){
    return -1;
  }
  return orig_write(fd, aBuf, nBuf);
}

/*
** A wrapper around pwrite().
*/
static int ts_pwrite(int fd, const void *aBuf, size_t nBuf, off_t off){
  if( tsIsFail() ){
    return -1;
  }
  return orig_pwrite(fd, aBuf, nBuf, off);
}

/*
** A wrapper around pwrite64().
*/
static int ts_pwrite64(int fd, const void *aBuf, size_t nBuf, off_t off){
  if( tsIsFail() ){
    return -1;
  }
  return orig_pwrite64(fd, aBuf, nBuf, off);
}

/*
** A wrapper around fchmod().
................................................................................
  int iErrno;
  int rc;

  struct Errno {
    const char *z;
    int i;
  } aErrno[] = {
    { "EACCES", EACCES },
    { "EINTR", EINTR },
    { "EIO", EIO },
    { "EOVERFLOW", EOVERFLOW },
    { "ENOMEM", ENOMEM },






    { 0, 0 }
  };

  if( objc!=4 ){
    Tcl_WrongNumArgs(interp, 2, objv, "SYSCALL ERRNO");
    return TCL_ERROR;
  }

  /*  0 */ { "open",      (sqlite3_syscall_ptr)ts_open,      0, EACCES, 0 },
  /*  1 */ { "close",     (sqlite3_syscall_ptr)ts_close,     0, 0, 0 },
  /*  2 */ { "access",    (sqlite3_syscall_ptr)ts_access,    0, 0, 0 },
  /*  3 */ { "getcwd",    (sqlite3_syscall_ptr)ts_getcwd,    0, 0, 0 },
  /*  4 */ { "stat",      (sqlite3_syscall_ptr)ts_stat,      0, 0, 0 },
  /*  5 */ { "fstat",     (sqlite3_syscall_ptr)ts_fstat,     0, 0, 0 },
  /*  6 */ { "ftruncate", (sqlite3_syscall_ptr)ts_ftruncate, 0, EIO, 0 },
  /*  7 */ { "fcntl",     (sqlite3_syscall_ptr)ts_fcntl,     0, EACCES, 0 },
  /*  8 */ { "read",      (sqlite3_syscall_ptr)ts_read,      0, 0, 0 },
  /*  9 */ { "pread",     (sqlite3_syscall_ptr)ts_pread,     0, 0, 0 },
  /* 10 */ { "pread64",   (sqlite3_syscall_ptr)ts_pread64,   0, 0, 0 },
  /* 11 */ { "write",     (sqlite3_syscall_ptr)ts_write,     0, 0, 0 },
  /* 12 */ { "pwrite",    (sqlite3_syscall_ptr)ts_pwrite,    0, 0, 0 },
  /* 13 */ { "pwrite64",  (sqlite3_syscall_ptr)ts_pwrite64,  0, 0, 0 },
  /* 14 */ { "fchmod",    (sqlite3_syscall_ptr)ts_fchmod,    0, 0, 0 },
................................................................................

/*
** A wrapper around fcntl().
*/
static int ts_fcntl(int fd, int cmd, ... ){
  va_list ap;
  void *pArg;
  if( tsIsFailErrno("fcntl") ){
    return -1;
  }
  va_start(ap, cmd);
  pArg = va_arg(ap, void *);
  return orig_fcntl(fd, cmd, pArg);
}

/*
** A wrapper around read().
*/
static int ts_read(int fd, void *aBuf, size_t nBuf){
  if( tsIsFailErrno("read") ){
    return -1;
  }
  return orig_read(fd, aBuf, nBuf);
}

/*
** A wrapper around pread().
*/
static int ts_pread(int fd, void *aBuf, size_t nBuf, off_t off){
  if( tsIsFailErrno("pread") ){
    return -1;
  }
  return orig_pread(fd, aBuf, nBuf, off);
}

/*
** A wrapper around pread64().
*/
static int ts_pread64(int fd, void *aBuf, size_t nBuf, off_t off){
  if( tsIsFailErrno("pread64") ){
    return -1;
  }
  return orig_pread64(fd, aBuf, nBuf, off);
}

/*
** A wrapper around write().
*/
static int ts_write(int fd, const void *aBuf, size_t nBuf){
  if( tsIsFailErrno("write") ){
    return -1;
  }
  return orig_write(fd, aBuf, nBuf);
}

/*
** A wrapper around pwrite().
*/
static int ts_pwrite(int fd, const void *aBuf, size_t nBuf, off_t off){
  if( tsIsFailErrno("pwrite") ){
    return -1;
  }
  return orig_pwrite(fd, aBuf, nBuf, off);
}

/*
** A wrapper around pwrite64().
*/
static int ts_pwrite64(int fd, const void *aBuf, size_t nBuf, off_t off){
  if( tsIsFailErrno("pwrite64") ){
    return -1;
  }
  return orig_pwrite64(fd, aBuf, nBuf, off);
}

/*
** A wrapper around fchmod().
................................................................................
  int iErrno;
  int rc;

  struct Errno {
    const char *z;
    int i;
  } aErrno[] = {
    { "EACCES",    EACCES },
    { "EINTR",     EINTR },
    { "EIO",       EIO },
    { "EOVERFLOW", EOVERFLOW },
    { "ENOMEM",    ENOMEM },
    { "EAGAIN",    EAGAIN },
    { "ETIMEDOUT", ETIMEDOUT },
    { "EBUSY",     EBUSY },
    { "EPERM",     EPERM },
    { "EDEADLK",   EDEADLK },
    { "ENOLCK",    ENOLCK },
    { 0, 0 }
  };

  if( objc!=4 ){
    Tcl_WrongNumArgs(interp, 2, objv, "SYSCALL ERRNO");
    return TCL_ERROR;
  }

}

/*
** Change the P2 operand of instruction addr so that it points to
** the address of the next instruction to be coded.
*/
void sqlite3VdbeJumpHere(Vdbe *p, int addr){

  sqlite3VdbeChangeP2(p, addr, p->nOp);
}


/*
** If the input FuncDef structure is ephemeral, then free it.  If
** the FuncDef is not ephermal, then do nothing.

}

/*
** Change the P2 operand of instruction addr so that it points to
** the address of the next instruction to be coded.
*/
void sqlite3VdbeJumpHere(Vdbe *p, int addr){
  assert( addr>=0 );
  sqlite3VdbeChangeP2(p, addr, p->nOp);
}


/*
** If the input FuncDef structure is ephemeral, then free it.  If
** the FuncDef is not ephermal, then do nothing.

    ** data is available for column x, then it might be possible
    ** to get a better estimate on the number of rows based on
    ** VALUE and how common that value is according to the histogram.
    */
    if( nRow>(double)1 && nEq==1 && pFirstTerm!=0 ){
      if( pFirstTerm->eOperator & (WO_EQ|WO_ISNULL) ){
        testcase( pFirstTerm->eOperator==WO_EQ );
        testcase( pFirstTerm->pOperator==WO_ISNULL );
        whereEqualScanEst(pParse, pProbe, pFirstTerm->pExpr->pRight, &nRow);
      }else if( pFirstTerm->eOperator==WO_IN && bInEst==0 ){
        whereInScanEst(pParse, pProbe, pFirstTerm->pExpr->x.pList, &nRow);
      }
    }
#endif /* SQLITE_ENABLE_STAT2 */

    ** data is available for column x, then it might be possible
    ** to get a better estimate on the number of rows based on
    ** VALUE and how common that value is according to the histogram.
    */
    if( nRow>(double)1 && nEq==1 && pFirstTerm!=0 ){
      if( pFirstTerm->eOperator & (WO_EQ|WO_ISNULL) ){
        testcase( pFirstTerm->eOperator==WO_EQ );
        testcase( pFirstTerm->eOperator==WO_ISNULL );
        whereEqualScanEst(pParse, pProbe, pFirstTerm->pExpr->pRight, &nRow);
      }else if( pFirstTerm->eOperator==WO_IN && bInEst==0 ){
        whereInScanEst(pParse, pProbe, pFirstTerm->pExpr->x.pList, &nRow);
      }
    }
#endif /* SQLITE_ENABLE_STAT2 */

} {1 {Cannot add a UNIQUE column}}
do_test alter-14.2 {
  catchsql {
    ALTER TABLE t3651 ADD COLUMN b PRIMARY KEY;
  }
} {1 {Cannot add a PRIMARY KEY column}}





















finish_test

} {1 {Cannot add a UNIQUE column}}
do_test alter-14.2 {
  catchsql {
    ALTER TABLE t3651 ADD COLUMN b PRIMARY KEY;
  }
} {1 {Cannot add a PRIMARY KEY column}}


#-------------------------------------------------------------------------
# Test that it is not possible to use ALTER TABLE on any system table.
#
set system_table_list {1 sqlite_master}
catchsql ANALYZE
ifcapable analyze { lappend system_table_list 2 sqlite_stat1 }
ifcapable stat2   { lappend system_table_list 3 sqlite_stat2 }

foreach {tn tbl} $system_table_list {
  do_test alter-15.$tn.1 {
    catchsql "ALTER TABLE $tbl RENAME TO xyz"
  } [list 1 "table $tbl may not be altered"]

  do_test alter-15.$tn.2 {
    catchsql "ALTER TABLE $tbl ADD COLUMN xyz"
  } [list 1 "table $tbl may not be altered"]
}


finish_test

    ANALYZE main.t1;
  }
} {0 {}}
do_test analyze-1.11 {
  execsql {
    SELECT * FROM sqlite_stat1
  }
} {t1 {} 0}
do_test analyze-1.12 {
  catchsql {
    ANALYZE t1;
  }
} {0 {}}
do_test analyze-1.13 {
  execsql {
    SELECT * FROM sqlite_stat1
  }
} {t1 {} 0}

# Create some indices that can be analyzed.  But do not yet add
# data.  Without data in the tables, no analysis is done.
#
do_test analyze-2.1 {
  execsql {
    CREATE INDEX t1i1 ON t1(a);
    ANALYZE main.t1;
    SELECT * FROM sqlite_stat1 ORDER BY idx;
  }
} {t1 {} 0}
do_test analyze-2.2 {
  execsql {
    CREATE INDEX t1i2 ON t1(b);
    ANALYZE t1;
    SELECT * FROM sqlite_stat1 ORDER BY idx;
  }
} {t1 {} 0}
do_test analyze-2.3 {
  execsql {
    CREATE INDEX t1i3 ON t1(a,b);
    ANALYZE main;
    SELECT * FROM sqlite_stat1 ORDER BY idx;
  }
} {t1 {} 0}

# Start adding data to the table.  Verify that the analysis
# is done correctly.
#
do_test analyze-3.1 {
  execsql {
    INSERT INTO t1 VALUES(1,2);

    ANALYZE main.t1;
  }
} {0 {}}
do_test analyze-1.11 {
  execsql {
    SELECT * FROM sqlite_stat1
  }
} {}
do_test analyze-1.12 {
  catchsql {
    ANALYZE t1;
  }
} {0 {}}
do_test analyze-1.13 {
  execsql {
    SELECT * FROM sqlite_stat1
  }
} {}

# Create some indices that can be analyzed.  But do not yet add
# data.  Without data in the tables, no analysis is done.
#
do_test analyze-2.1 {
  execsql {
    CREATE INDEX t1i1 ON t1(a);
    ANALYZE main.t1;
    SELECT * FROM sqlite_stat1 ORDER BY idx;
  }
} {}
do_test analyze-2.2 {
  execsql {
    CREATE INDEX t1i2 ON t1(b);
    ANALYZE t1;
    SELECT * FROM sqlite_stat1 ORDER BY idx;
  }
} {}
do_test analyze-2.3 {
  execsql {
    CREATE INDEX t1i3 ON t1(a,b);
    ANALYZE main;
    SELECT * FROM sqlite_stat1 ORDER BY idx;
  }
} {}

# Start adding data to the table.  Verify that the analysis
# is done correctly.
#
do_test analyze-3.1 {
  execsql {
    INSERT INTO t1 VALUES(1,2);

# FROM clause.
#
do_test analyze6-1.2 {
  eqp {SELECT count(*) FROM cat, ev WHERE x=y}
} {0 0 0 {SCAN TABLE cat (~16 rows)} 0 1 1 {SEARCH TABLE ev USING COVERING INDEX evy (y=?) (~32 rows)}}


















































finish_test

# FROM clause.
#
do_test analyze6-1.2 {
  eqp {SELECT count(*) FROM cat, ev WHERE x=y}
} {0 0 0 {SCAN TABLE cat (~16 rows)} 0 1 1 {SEARCH TABLE ev USING COVERING INDEX evy (y=?) (~32 rows)}}


# Ticket [83ea97620bd3101645138b7b0e71c12c5498fe3d] 2011-03-30
# If ANALYZE is run on an empty table, make sure indices are used
# on the table.
#
do_test analyze6-2.1 {
  execsql {
    CREATE TABLE t201(x INTEGER PRIMARY KEY, y UNIQUE, z);
    CREATE INDEX t201z ON t201(z);
    ANALYZE;
  }
  eqp {SELECT * FROM t201 WHERE z=5}
} {0 0 0 {SEARCH TABLE t201 USING INDEX t201z (z=?) (~10 rows)}}
do_test analyze6-2.2 {
  eqp {SELECT * FROM t201 WHERE y=5}
} {0 0 0 {SEARCH TABLE t201 USING INDEX sqlite_autoindex_t201_1 (y=?) (~1 rows)}}
do_test analyze6-2.3 {
  eqp {SELECT * FROM t201 WHERE x=5}
} {0 0 0 {SEARCH TABLE t201 USING INTEGER PRIMARY KEY (rowid=?) (~1 rows)}}
do_test analyze6-2.4 {
  execsql {
    INSERT INTO t201 VALUES(1,2,3);
    ANALYZE t201;
  }
  eqp {SELECT * FROM t201 WHERE z=5}
} {0 0 0 {SEARCH TABLE t201 USING INDEX t201z (z=?) (~10 rows)}}
do_test analyze6-2.5 {
  eqp {SELECT * FROM t201 WHERE y=5}
} {0 0 0 {SEARCH TABLE t201 USING INDEX sqlite_autoindex_t201_1 (y=?) (~1 rows)}}
do_test analyze6-2.6 {
  eqp {SELECT * FROM t201 WHERE x=5}
} {0 0 0 {SEARCH TABLE t201 USING INTEGER PRIMARY KEY (rowid=?) (~1 rows)}}
do_test analyze6-2.7 {
  execsql {
    INSERT INTO t201 VALUES(4,5,7);
    INSERT INTO t201 SELECT x+100, y+100, z+100 FROM t201;
    INSERT INTO t201 SELECT x+200, y+200, z+200 FROM t201;
    INSERT INTO t201 SELECT x+400, y+400, z+400 FROM t201;
    ANALYZE t201;
  }
  eqp {SELECT * FROM t201 WHERE z=5}
} {0 0 0 {SEARCH TABLE t201 USING INDEX t201z (z=?) (~10 rows)}}
do_test analyze6-2.8 {
  eqp {SELECT * FROM t201 WHERE y=5}
} {0 0 0 {SEARCH TABLE t201 USING INDEX sqlite_autoindex_t201_1 (y=?) (~1 rows)}}
do_test analyze6-2.9 {
  eqp {SELECT * FROM t201 WHERE x=5}
} {0 0 0 {SEARCH TABLE t201 USING INTEGER PRIMARY KEY (rowid=?) (~1 rows)}}

finish_test

# 2011 April 1
#
# The author disclaims copyright to this source code.  In place of
# 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.
#
#***********************************************************************
# This file implements regression tests for SQLite library.
# This file implements tests for the ANALYZE command when an idnex
# name is given as the argument.
#

set testdir [file dirname $argv0]
source $testdir/tester.tcl

# There is nothing to test if ANALYZE is disable for this build.
#
ifcapable {!analyze} {
  finish_test
  return
}

# Generate some test data
#
do_test analyze7-1.0 {
  execsql {
    CREATE TABLE sequence(x INTEGER PRIMARY KEY);
    INSERT INTO sequence VALUES(1);
    INSERT INTO sequence VALUES(2);
    INSERT INTO sequence SELECT x+2 FROM sequence;
    INSERT INTO sequence SELECT x+4 FROM sequence;
    INSERT INTO sequence SELECT x+8 FROM sequence;
    INSERT INTO sequence SELECT x+16 FROM sequence;
    INSERT INTO sequence SELECT x+32 FROM sequence;
    INSERT INTO sequence SELECT x+64 FROM sequence;
    INSERT INTO sequence SELECT x+128 FROM sequence;
    INSERT INTO sequence SELECT x+256 FROM sequence;
    CREATE TABLE t1(a,b,c,d);
    CREATE INDEX t1a ON t1(a);
    CREATE INDEX t1b ON t1(b);
    CREATE INDEX t1cd ON t1(c,d);
    INSERT INTO t1 SELECT x, x, x/100, x FROM sequence;
    EXPLAIN QUERY PLAN SELECT * FROM t1 WHERE a=123;
  }
} {0 0 0 {SEARCH TABLE t1 USING INDEX t1a (a=?) (~10 rows)}}
do_test analyze7-1.1 {
  execsql {EXPLAIN QUERY PLAN SELECT * FROM t1 WHERE b=123;}
} {0 0 0 {SEARCH TABLE t1 USING INDEX t1b (b=?) (~10 rows)}}
do_test analyze7-1.2 {
  execsql {EXPLAIN QUERY PLAN SELECT * FROM t1 WHERE c=2;}
} {0 0 0 {SEARCH TABLE t1 USING INDEX t1cd (c=?) (~10 rows)}}

# Run an analyze on one of the three indices.  Verify that this
# effects the row-count estimate on the one query that uses that
# one index.
#
do_test analyze7-2.0 {
  execsql {ANALYZE t1a;}
  db cache flush
  execsql {EXPLAIN QUERY PLAN SELECT * FROM t1 WHERE a=123;}
} {0 0 0 {SEARCH TABLE t1 USING INDEX t1a (a=?) (~1 rows)}}
do_test analyze7-2.1 {
  execsql {EXPLAIN QUERY PLAN SELECT * FROM t1 WHERE b=123;}
} {0 0 0 {SEARCH TABLE t1 USING INDEX t1b (b=?) (~10 rows)}}
do_test analyze7-2.2 {
  execsql {EXPLAIN QUERY PLAN SELECT * FROM t1 WHERE c=2;}
} {0 0 0 {SEARCH TABLE t1 USING INDEX t1cd (c=?) (~10 rows)}}

# Verify that since the query planner now things that t1a is more
# selective than t1b, it prefers to use t1a.
#
do_test analyze7-2.3 {
  execsql {EXPLAIN QUERY PLAN SELECT * FROM t1 WHERE a=123 AND b=123}
} {0 0 0 {SEARCH TABLE t1 USING INDEX t1a (a=?) (~1 rows)}}

# Run an analysis on another of the three indices.  Verify  that this
# new analysis works and does not disrupt the previous analysis.
#
do_test analyze7-3.0 {
  execsql {ANALYZE t1cd;}
  db cache flush;
  execsql {EXPLAIN QUERY PLAN SELECT * FROM t1 WHERE a=123;}
} {0 0 0 {SEARCH TABLE t1 USING INDEX t1a (a=?) (~1 rows)}}
do_test analyze7-3.1 {
  execsql {EXPLAIN QUERY PLAN SELECT * FROM t1 WHERE b=123;}
} {0 0 0 {SEARCH TABLE t1 USING INDEX t1b (b=?) (~10 rows)}}
do_test analyze7-3.2 {
  execsql {EXPLAIN QUERY PLAN SELECT * FROM t1 WHERE c=2;}
} {0 0 0 {SEARCH TABLE t1 USING INDEX t1cd (c=?) (~102 rows)}}
do_test analyze7-3.3 {
  execsql {EXPLAIN QUERY PLAN SELECT * FROM t1 WHERE a=123 AND b=123}
} {0 0 0 {SEARCH TABLE t1 USING INDEX t1a (a=?) (~1 rows)}}
do_test analyze7-3.4 {
  execsql {EXPLAIN QUERY PLAN SELECT * FROM t1 WHERE c=123 AND b=123}
} {0 0 0 {SEARCH TABLE t1 USING INDEX t1b (b=?) (~2 rows)}}
do_test analyze7-3.5 {
  execsql {EXPLAIN QUERY PLAN SELECT * FROM t1 WHERE a=123 AND c=123}
} {0 0 0 {SEARCH TABLE t1 USING INDEX t1a (a=?) (~1 rows)}}
do_test analyze7-3.6 {
  execsql {EXPLAIN QUERY PLAN SELECT * FROM t1 WHERE c=123 AND d=123 AND b=123}
} {0 0 0 {SEARCH TABLE t1 USING INDEX t1cd (c=? AND d=?) (~1 rows)}}

finish_test

  do_test badutf2-4.1.$i {
    sqlite3_reset $S
    sqlite3_bind_text $S 1 $xstr $len
    sqlite3_step $S
    utf8_to_ustr2 [ sqlite3_column_text $S 0 ]
  } $ustr


  do_test badutf2-5.1.$i {
    utf8_to_utf8 $uval
  } $u2u


}

do_test badutf2-4.2 {
  sqlite3_finalize $S
} {SQLITE_OK}


finish_test

  do_test badutf2-4.1.$i {
    sqlite3_reset $S
    sqlite3_bind_text $S 1 $xstr $len
    sqlite3_step $S
    utf8_to_ustr2 [ sqlite3_column_text $S 0 ]
  } $ustr

  ifcapable debug {
    do_test badutf2-5.1.$i {
      utf8_to_utf8 $uval
    } $u2u
  }

}

do_test badutf2-4.2 {
  sqlite3_finalize $S
} {SQLITE_OK}


finish_test

  
}

#--------------------------------------------------------------------------
# Tests oserror-1.* test failures in the open() system call.
#

# Test a failure in open() due to too many files.





#
do_test 1.1.1 {
  set ::log [list]
  list [catch {
    for {set i 0} {$i < 2000} {incr i} { sqlite3 dbh_$i test.db -readonly 1 }
  } msg] $msg
} {1 {unable to open database file}}
do_test 1.1.2 {
  catch { for {set i 0} {$i < 2000} {incr i} { dbh_$i close } }
} {1}

do_re_test 1.1.3 { lindex $::log 0 } {^os_unix.c:\d+: \(\d+\) open\(.*test.db\) - }



# Test a failure in open() due to the path being a directory.
#
do_test 1.2.1 {
  file mkdir dir.db
  set ::log [list]

  
}

#--------------------------------------------------------------------------
# Tests oserror-1.* test failures in the open() system call.
#

# Test a failure in open() due to too many files. 
#
# The xOpen() method of the unix VFS calls getcwd() as well as open().
# Although this does not appear to be documented in the man page, on OSX
# a call to getcwd() may fail if there are no free file descriptors. So
# an error may be reported for either open() or getcwd() here.
#
do_test 1.1.1 {
  set ::log [list]
  list [catch {
    for {set i 0} {$i < 2000} {incr i} { sqlite3 dbh_$i test.db -readonly 1 }
  } msg] $msg
} {1 {unable to open database file}}
do_test 1.1.2 {
  catch { for {set i 0} {$i < 2000} {incr i} { dbh_$i close } }
} {1}
do_re_test 1.1.3 { 
  lindex $::log 0 
} {^os_unix.c:\d+: \(\d+\) (open|getcwd)\(.*test.db\) - }


# Test a failure in open() due to the path being a directory.
#
do_test 1.2.1 {
  file mkdir dir.db
  set ::log [list]

    INSERT INTO tt SELECT randomblob(500), randomblob(600) FROM tt;
    INSERT INTO tt SELECT randomblob(500), randomblob(600) FROM tt;
    INSERT INTO tt SELECT randomblob(500), randomblob(600) FROM tt;
  }

  db close
} {}






















































finish_test

    INSERT INTO tt SELECT randomblob(500), randomblob(600) FROM tt;
    INSERT INTO tt SELECT randomblob(500), randomblob(600) FROM tt;
    INSERT INTO tt SELECT randomblob(500), randomblob(600) FROM tt;
  }

  db close
} {}

#-------------------------------------------------------------------------
# Test that a database file a single byte in size is treated as an empty
# file. Whereas a file 2 bytes or larger might be considered corrupt.
#
catch { db close }
forcedelete test.db test.db2

proc create_db_file {nByte} {
  set fd [open test.db w]
  fconfigure $fd -translation binary -encoding binary
  puts -nonewline $fd [string range "xSQLite" 1 $nByte]
  close $fd
}

foreach {nByte res} {
  1      {0 {}}
  2      {1 {file is encrypted or is not a database}}
  3      {1 {file is encrypted or is not a database}}
} {
  do_test 7.$nByte {
    create_db_file $nByte
    sqlite3 db test.db
    catchsql { CREATE TABLE t1(a, b) }
  } $res
  catch { db close }
}

#-------------------------------------------------------------------------
# 
catch { db close }
forcedelete test.db test.db2

do_test 8.1 {
  sqlite3 db test.db
  file_control_chunksize_test db main 4096
  file size test.db
} {0}

foreach {tn hint size} {
  1  1000    4096 
  2  1000    4096 
  3  3000    4096 
  4  4096    4096 
  5  4197    8192 
} {
  do_test 8.2.$tn {
    file_control_sizehint_test db main $hint
    file size test.db
  } $size
}



finish_test

  faultsim_restore
} -body $open_and_write_body -test {
  faultsim_test_result {0 {wal 1 2 3 4}}       \
    {1 {unable to open database file}}         \
    {1 {attempt to write a readonly database}}
}


# Errors in the fstat() function when opening and writing a file.



#
foreach {tn errno errlist} {
  1 ENOMEM       {{disk I/O error}}
  2 EOVERFLOW    {{disk I/O error} {large file support is disabled}}
} {
  proc vfsfault_install {} { test_syscall install fstat }
  set errs [list]
................................................................................
  } -body "
    test_syscall errno fstat $errno
    $open_and_write_body 
  " -test "
    faultsim_test_result {0 {wal 1 2 3 4}} $errs
  "
}














































#-------------------------------------------------------------------------
# Check that a single EINTR error does not affect processing.
#
proc vfsfault_install {} { 
  test_syscall reset
  test_syscall install {open ftruncate close}
}

forcedelete test.db test.db2
sqlite3 db test.db
do_test 2.setup {
  execsql {
    CREATE TABLE t1(a, b, c, PRIMARY KEY(a));
................................................................................
do_faultsim_test 2.1 -faults vfsfault-transient -prep {
  catch { db close }
  faultsim_restore
} -body {
  test_syscall errno open      EINTR
  test_syscall errno ftruncate EINTR
  test_syscall errno close     EINTR






  sqlite3 db test.db


  set res [db eval {
    ATTACH 'test.db2' AS 'aux';
    SELECT * FROM t1;
    PRAGMA journal_mode = truncate;
    BEGIN;
      INSERT INTO t1 VALUES('jkl', 'mno', 'pqr');

      UPDATE t2 SET x = 2;
    COMMIT;

    SELECT * FROM t1;
    SELECT * FROM t2;
  }]
  db close
  set res
} -test {
  faultsim_test_result {0 {abc def ghi truncate abc def ghi jkl mno pqr 2}}
................................................................................
    {1 {unable to open database file}}                                      \
    {1 {unable to open database: test.db2}}                                 \
    {1 {attempt to write a readonly database}}                              \
    {1 {disk I/O error}}                                                  
}

#-------------------------------------------------------------------------
# 

























finish_test

  faultsim_restore
} -body $open_and_write_body -test {
  faultsim_test_result {0 {wal 1 2 3 4}}       \
    {1 {unable to open database file}}         \
    {1 {attempt to write a readonly database}}
}

#-------------------------------------------------------------------------
# Errors in the fstat() function when opening and writing a file. Cases
# where fstat() fails and sets errno to ENOMEM and EOVERFLOW are both
# tested. EOVERFLOW is interpreted as meaning that a file on disk is
# too large to be opened by the OS.
#
foreach {tn errno errlist} {
  1 ENOMEM       {{disk I/O error}}
  2 EOVERFLOW    {{disk I/O error} {large file support is disabled}}
} {
  proc vfsfault_install {} { test_syscall install fstat }
  set errs [list]
................................................................................
  } -body "
    test_syscall errno fstat $errno
    $open_and_write_body 
  " -test "
    faultsim_test_result {0 {wal 1 2 3 4}} $errs
  "
}

#-------------------------------------------------------------------------
# Various errors in locking functions. 
#
foreach vfs {unix unix-excl} {
  foreach {tn errno errlist} {
    1 EAGAIN       {{database is locked} {disk I/O error}}
    2 ETIMEDOUT    {{database is locked} {disk I/O error}}
    3 EBUSY        {{database is locked} {disk I/O error}}
    4 EINTR        {{database is locked} {disk I/O error}}
    5 ENOLCK       {{database is locked} {disk I/O error}}
    6 EACCES       {{database is locked} {disk I/O error}}
    7 EPERM        {{access permission denied} {disk I/O error}}
    8 EDEADLK      {{disk I/O error}}
    9 ENOMEM       {{disk I/O error}}
  } {
    proc vfsfault_install {} { test_syscall install fcntl }
    set errs [list]
    foreach e $errlist { lappend errs [list 1 $e] }
  
    set body [string map [list %VFS% $vfs] {
      sqlite3 db test.db
      db eval {
        CREATE TABLE t1(a, b);
        INSERT INTO t1 VALUES(1, 2);
      }
      set fd [open test.db-journal w]
      puts $fd "hello world"
      close $fd
      sqlite3 db test.db -vfs %VFS%
      db eval {
        SELECT * FROM t1;
      }
    }]
  
    do_faultsim_test 1.3.$vfs.$tn -faults vfsfault-* -prep {
      faultsim_restore
    } -body "
      test_syscall errno fcntl $errno
      $body
    " -test "
      faultsim_test_result {0 {1 2}} $errs
    "
  }
}

#-------------------------------------------------------------------------
# Check that a single EINTR error does not affect processing.
#
proc vfsfault_install {} { 
  test_syscall reset
  test_syscall install {open ftruncate close read pread pread64 write fallocate}
}

forcedelete test.db test.db2
sqlite3 db test.db
do_test 2.setup {
  execsql {
    CREATE TABLE t1(a, b, c, PRIMARY KEY(a));
................................................................................
do_faultsim_test 2.1 -faults vfsfault-transient -prep {
  catch { db close }
  faultsim_restore
} -body {
  test_syscall errno open      EINTR
  test_syscall errno ftruncate EINTR
  test_syscall errno close     EINTR
  test_syscall errno read      EINTR
  test_syscall errno pread     EINTR
  test_syscall errno pread64   EINTR
  test_syscall errno write     EINTR
  test_syscall errno fallocate EINTR

  sqlite3 db test.db
  file_control_chunksize_test db main 8192

  set res [db eval {
    ATTACH 'test.db2' AS 'aux';
    SELECT * FROM t1;
    PRAGMA journal_mode = truncate;
    BEGIN;
      INSERT INTO t1 VALUES('jkl', 'mno', 'pqr');
      INSERT INTO t1 VALUES(randomblob(10000), 0, 0);
      UPDATE t2 SET x = 2;
    COMMIT;
    DELETE FROM t1 WHERE length(a)>3;
    SELECT * FROM t1;
    SELECT * FROM t2;
  }]
  db close
  set res
} -test {
  faultsim_test_result {0 {abc def ghi truncate abc def ghi jkl mno pqr 2}}
................................................................................
    {1 {unable to open database file}}                                      \
    {1 {unable to open database: test.db2}}                                 \
    {1 {attempt to write a readonly database}}                              \
    {1 {disk I/O error}}                                                  
}

#-------------------------------------------------------------------------

proc vfsfault_install {} { 
  test_syscall reset
  test_syscall install {fstat fallocate}
}
do_faultsim_test 3 -faults vfsfault-* -prep {
  faultsim_delete_and_reopen
  file_control_chunksize_test db main 8192
  execsql {
    CREATE TABLE t1(a, b);
    BEGIN;
      SELECT * FROM t1;
  }
} -body {
  test_syscall errno fstat     EIO
  test_syscall errno fallocate EIO

  execsql {
    INSERT INTO t1 VALUES(randomblob(10000), randomblob(10000));
    SELECT length(a) + length(b) FROM t1;
    COMMIT;
  }
} -test {
  faultsim_test_result {0 20000}
}

finish_test

# 2011 March 30
#
# The author disclaims copyright to this source code.  In place of
# 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.
#
#***********************************************************************
#
# This file contains tests for the "unix-excl" VFS module (part of 
# os_unix.c).
#

set testdir [file dirname $argv0]
source $testdir/tester.tcl
source $testdir/lock_common.tcl
source $testdir/malloc_common.tcl

if {$::tcl_platform(platform)!="unix" || [info commands test_syscall]==""} {
  finish_test
  return
} 
set testprefix unixexcl



# Test that when using VFS "unix-excl", the first time the database is read
# a process-wide exclusive lock is taken on it. This means other connections
# within the process may still access the db normally, but connections from
# outside the process cannot.
#
do_multiclient_test tn {
  do_test unixexcl-1.$tn.1 {
    sql1 {
      CREATE TABLE t1(a, b);
      INSERT INTO t1 VALUES('hello', 'world');
    }
  } {}
  do_test unixexcl-1.$tn.2 { sql2 { SELECT * FROM t1 } } {hello world}
  do_test unixexcl-1.$tn.3 {
    code1 {
      db close
      sqlite3 db test.db -vfs unix-excl
      db eval { SELECT * FROM t1 }
    }
  } {hello world}
  if {$tn==1} {
    do_test unixexcl-1.$tn.4.multiproc { 
      csql2 { SELECT * FROM t1 } 
    } {1 {database is locked}}
  } else {
    do_test unixexcl-1.$tn.4.singleproc { 
      csql2 { SELECT * FROM t1 } 
    } {0 {hello world}}
  }
}

# Test that when using VFS "unix-excl", if a file is opened in read-only mode
# the behaviour is the same as if VFS "unix" were used.
#
do_multiclient_test tn {
  do_test unixexcl-2.$tn.1 {
    sql1 {
      CREATE TABLE t1(a, b);
      INSERT INTO t1 VALUES('hello', 'world');
    }
  } {}
  do_test unixexcl-2.$tn.2 { sql2 { SELECT * FROM t1 } } {hello world}
  do_test unixexcl-2.$tn.3 {
    code1 {
      db close
      sqlite3 db test.db -readonly yes -vfs unix-excl
      db eval { SELECT * FROM t1 }
    }
  } {hello world}
  do_test unixexcl-2.$tn.4 { 
    csql2 { SELECT * FROM t1 } 
  } {0 {hello world}}
}

finish_test

# if held until an inner loop.
# 
do_execsql_test where3-3.0 {
  CREATE TABLE t301(a INTEGER PRIMARY KEY,b,c);
  CREATE INDEX t301c ON t301(c);
  INSERT INTO t301 VALUES(1,2,3);
  CREATE TABLE t302(x, y);

  ANALYZE;
  explain query plan SELECT * FROM t302, t301 WHERE t302.x=5 AND t301.a=t302.y;
} {
  0 0 0 {SCAN TABLE t302 (~1 rows)} 
  0 1 1 {SEARCH TABLE t301 USING INTEGER PRIMARY KEY (rowid=?) (~1 rows)}
}
do_execsql_test where3-3.1 {
................................................................................
      AND bbb.parent = 4
    ORDER BY bbb.title COLLATE NOCASE ASC;
} {
  0 0 1 {SEARCH TABLE aaa USING INDEX aaa_333 (fk=?) (~10 rows)} 
  0 1 0 {SEARCH TABLE aaa AS bbb USING INTEGER PRIMARY KEY (rowid=?) (~1 rows)} 
  0 0 0 {USE TEMP B-TREE FOR ORDER BY}
}


finish_test

# if held until an inner loop.
# 
do_execsql_test where3-3.0 {
  CREATE TABLE t301(a INTEGER PRIMARY KEY,b,c);
  CREATE INDEX t301c ON t301(c);
  INSERT INTO t301 VALUES(1,2,3);
  CREATE TABLE t302(x, y);
  INSERT INTO t302 VALUES(4,5);
  ANALYZE;
  explain query plan SELECT * FROM t302, t301 WHERE t302.x=5 AND t301.a=t302.y;
} {
  0 0 0 {SCAN TABLE t302 (~1 rows)} 
  0 1 1 {SEARCH TABLE t301 USING INTEGER PRIMARY KEY (rowid=?) (~1 rows)}
}
do_execsql_test where3-3.1 {
................................................................................
      AND bbb.parent = 4
    ORDER BY bbb.title COLLATE NOCASE ASC;
} {
  0 0 1 {SEARCH TABLE aaa USING INDEX aaa_333 (fk=?) (~10 rows)} 
  0 1 0 {SEARCH TABLE aaa AS bbb USING INTEGER PRIMARY KEY (rowid=?) (~1 rows)} 
  0 0 0 {USE TEMP B-TREE FOR ORDER BY}
}


finish_test