#
all:	sqlite3.h libsqlite3.a sqlite3$(EXE)

libsqlite3.a:	$(LIBOBJ)
	$(AR) libsqlite3.a $(LIBOBJ)
	$(RANLIB) libsqlite3.a

sqlite3$(EXE):	$(TOP)/src/shell.c libsqlite3.a sqlite3.h
	$(TCCX) $(READLINE_FLAGS) -o sqlite3$(EXE) $(SHELL_OPT) \
		$(TOP)/src/shell.c libsqlite3.a $(LIBREADLINE) $(TLIBS) $(THREADLIB)

sqldiff$(EXE):	$(TOP)/tool/sqldiff.c sqlite3.c sqlite3.h
	$(TCCX) -o sqldiff$(EXE) -DSQLITE_THREADSAFE=0 \
		$(TOP)/tool/sqldiff.c sqlite3.c $(TLIBS) $(THREADLIB)

#
all:	sqlite3.h libsqlite3.a sqlite3$(EXE)

libsqlite3.a:	$(LIBOBJ)
	$(AR) libsqlite3.a $(LIBOBJ)
	$(RANLIB) libsqlite3.a

sqlite3$(EXE):	$(TOP)/src/shell.c libsqlite3.a sqlite3.h $(TOP)/src/shell_indexes.c
	$(TCCX) $(READLINE_FLAGS) -o sqlite3$(EXE) $(SHELL_OPT) \
		$(TOP)/src/shell.c libsqlite3.a $(LIBREADLINE) $(TLIBS) $(THREADLIB)

sqldiff$(EXE):	$(TOP)/tool/sqldiff.c sqlite3.c sqlite3.h
	$(TCCX) -o sqldiff$(EXE) -DSQLITE_THREADSAFE=0 \
		$(TOP)/tool/sqldiff.c sqlite3.c $(TLIBS) $(THREADLIB)

    case SQLITE_DBCONFIG_LOOKASIDE: {
      void *pBuf = va_arg(ap, void*); /* IMP: R-26835-10964 */
      int sz = va_arg(ap, int);       /* IMP: R-47871-25994 */
      int cnt = va_arg(ap, int);      /* IMP: R-04460-53386 */
      rc = setupLookaside(db, pBuf, sz, cnt);
      break;
    }







    default: {
      static const struct {
        int op;      /* The opcode */
        u32 mask;    /* Mask of the bit in sqlite3.flags to set/clear */
      } aFlagOp[] = {
        { SQLITE_DBCONFIG_ENABLE_FKEY,    SQLITE_ForeignKeys    },
        { SQLITE_DBCONFIG_ENABLE_TRIGGER, SQLITE_EnableTrigger  },

    case SQLITE_DBCONFIG_LOOKASIDE: {
      void *pBuf = va_arg(ap, void*); /* IMP: R-26835-10964 */
      int sz = va_arg(ap, int);       /* IMP: R-47871-25994 */
      int cnt = va_arg(ap, int);      /* IMP: R-04460-53386 */
      rc = setupLookaside(db, pBuf, sz, cnt);
      break;
    }
#ifdef SQLITE_SCHEMA_LINT
    case SQLITE_DBCONFIG_WHEREINFO: {
      db->xWhereInfo = va_arg(ap, void(*)(void*, int, const char*, int, i64));
      db->pWhereInfoCtx = va_arg(ap, void*);
      break;
    }
#endif
    default: {
      static const struct {
        int op;      /* The opcode */
        u32 mask;    /* Mask of the bit in sqlite3.flags to set/clear */
      } aFlagOp[] = {
        { SQLITE_DBCONFIG_ENABLE_FKEY,    SQLITE_ForeignKeys    },
        { SQLITE_DBCONFIG_ENABLE_TRIGGER, SQLITE_EnableTrigger  },

  ** the returned data set are:
  **
  ** cid:        Column id (numbered from left to right, starting at 0)
  ** name:       Column name
  ** type:       Column declaration type.
  ** notnull:    True if 'NOT NULL' is part of column declaration
  ** dflt_value: The default value for the column, if any.

  */
  case PragTyp_TABLE_INFO: if( zRight ){
    Table *pTab;
    pTab = sqlite3FindTable(db, zRight, zDb);
    if( pTab ){
      static const char *azCol[] = {
         "cid", "name", "type", "notnull", "dflt_value", "pk"

  ** the returned data set are:
  **
  ** cid:        Column id (numbered from left to right, starting at 0)
  ** name:       Column name
  ** type:       Column declaration type.
  ** notnull:    True if 'NOT NULL' is part of column declaration
  ** dflt_value: The default value for the column, if any.
  ** pk:         Non-zero for PK fields.
  */
  case PragTyp_TABLE_INFO: if( zRight ){
    Table *pTab;
    pTab = sqlite3FindTable(db, zRight, zDb);
    if( pTab ){
      static const char *azCol[] = {
         "cid", "name", "type", "notnull", "dflt_value", "pk"

  _setmode(_fileno(out), _O_TEXT);
}
#else
# define setBinaryMode(X)
# define setTextMode(X)
#endif



/* True if the timer is enabled */
static int enableTimer = 0;

/* Return the current wall-clock time */
static sqlite3_int64 timeOfDay(void){
  static sqlite3_vfs *clockVfs = 0;
................................................................................
** State information about the database connection is contained in an
** instance of the following structure.
*/
typedef struct ShellState ShellState;
struct ShellState {
  sqlite3 *db;           /* The database */
  int echoOn;            /* True to echo input commands */
  int autoEQP;           /* Run EXPLAIN QUERY PLAN prior to seach SQL stmt */

  int statsOn;           /* True to display memory stats before each finalize */
  int scanstatsOn;       /* True to display scan stats before each finalize */
  int countChanges;      /* True to display change counts */
  int backslashOn;       /* Resolve C-style \x escapes in SQL input text */
  int outCount;          /* Revert to stdout when reaching zero */
  int cnt;               /* Number of records displayed so far */
  FILE *out;             /* Write results here */
................................................................................
*/
static void explain_data_delete(ShellState *p){
  sqlite3_free(p->aiIndent);
  p->aiIndent = 0;
  p->nIndent = 0;
  p->iIndent = 0;
}














/*
** Execute a statement or set of statements.  Print 
** any result rows/columns depending on the current mode 
** set via the supplied callback.
**
** This is very similar to SQLite's built-in sqlite3_exec() 
................................................................................
  int rc = SQLITE_OK;             /* Return Code */
  int rc2;
  const char *zLeftover;          /* Tail of unprocessed SQL */

  if( pzErrMsg ){
    *pzErrMsg = NULL;
  }








  while( zSql[0] && (SQLITE_OK == rc) ){
    rc = sqlite3_prepare_v2(db, zSql, -1, &pStmt, &zLeftover);
    if( SQLITE_OK != rc ){
      if( pzErrMsg ){
        *pzErrMsg = save_err_msg(db);
      }
................................................................................
    }else{
      utf8_printf(stderr, "Error: %s\n", sqlite3_errmsg(p->db));
      rc = 1;
    }
    sqlite3_close(pSrc);
  }else











  if( c=='s' && strncmp(azArg[0], "scanstats", n)==0 ){
    if( nArg==2 ){
      p->scanstatsOn = booleanValue(azArg[1]);
#ifndef SQLITE_ENABLE_STMT_SCANSTATUS
      raw_printf(stderr, "Warning: .scanstats not available in this build.\n");
#endif
................................................................................
          utf8_printf(stderr,"Error: %s\n", zErrMsg);
          if( bail_on_error ) return rc!=0 ? rc : 1;
        }else if( rc!=0 ){
          utf8_printf(stderr,"Error: unable to process SQL \"%s\"\n", z);
          if( bail_on_error ) return rc;
        }
      }



    }else{
      utf8_printf(stderr,"%s: Error: unknown option: %s\n", Argv0, z);
      raw_printf(stderr,"Use -help for a list of options.\n");
      return 1;
    }
  }

  _setmode(_fileno(out), _O_TEXT);
}
#else
# define setBinaryMode(X)
# define setTextMode(X)
#endif

#include "shell_indexes.c"

/* True if the timer is enabled */
static int enableTimer = 0;

/* Return the current wall-clock time */
static sqlite3_int64 timeOfDay(void){
  static sqlite3_vfs *clockVfs = 0;
................................................................................
** State information about the database connection is contained in an
** instance of the following structure.
*/
typedef struct ShellState ShellState;
struct ShellState {
  sqlite3 *db;           /* The database */
  int echoOn;            /* True to echo input commands */
  int autoEQP;           /* Run EXPLAIN QUERY PLAN prior to each SQL stmt */
  int bRecommend;        /* Instead of sqlite3_exec(), recommend indexes */
  int statsOn;           /* True to display memory stats before each finalize */
  int scanstatsOn;       /* True to display scan stats before each finalize */
  int countChanges;      /* True to display change counts */
  int backslashOn;       /* Resolve C-style \x escapes in SQL input text */
  int outCount;          /* Revert to stdout when reaching zero */
  int cnt;               /* Number of records displayed so far */
  FILE *out;             /* Write results here */
................................................................................
*/
static void explain_data_delete(ShellState *p){
  sqlite3_free(p->aiIndent);
  p->aiIndent = 0;
  p->nIndent = 0;
  p->iIndent = 0;
}

typedef struct RecCommandCtx RecCommandCtx;
struct RecCommandCtx {
  int (*xCallback)(void*,int,char**,char**,int*);
  ShellState *pArg;
};

static void recCommandOut(void *pCtx, const char *zLine){
  const char *zCol = "output";
  RecCommandCtx *p = (RecCommandCtx*)pCtx;
  int t = SQLITE_TEXT;
  p->xCallback(p->pArg, 1, (char**)&zLine, (char**)&zCol, &t);
}

/*
** Execute a statement or set of statements.  Print 
** any result rows/columns depending on the current mode 
** set via the supplied callback.
**
** This is very similar to SQLite's built-in sqlite3_exec() 
................................................................................
  int rc = SQLITE_OK;             /* Return Code */
  int rc2;
  const char *zLeftover;          /* Tail of unprocessed SQL */

  if( pzErrMsg ){
    *pzErrMsg = NULL;
  }

  if( pArg->bRecommend ){
    RecCommandCtx ctx;
    ctx.xCallback = xCallback;
    ctx.pArg = pArg;
    rc = shellIndexesCommand(db, zSql, recCommandOut, &ctx, pzErrMsg);
  }else

  while( zSql[0] && (SQLITE_OK == rc) ){
    rc = sqlite3_prepare_v2(db, zSql, -1, &pStmt, &zLeftover);
    if( SQLITE_OK != rc ){
      if( pzErrMsg ){
        *pzErrMsg = save_err_msg(db);
      }
................................................................................
    }else{
      utf8_printf(stderr, "Error: %s\n", sqlite3_errmsg(p->db));
      rc = 1;
    }
    sqlite3_close(pSrc);
  }else

  if( c=='r' && n>=2 && strncmp(azArg[0], "recommend", n)==0 ){
    if( nArg==2 ){
      p->bRecommend = booleanValue(azArg[1]);
    }else{
      raw_printf(stderr, "Usage: .recommend on|off\n");
      rc = 1;
    }
  }else


  if( c=='s' && strncmp(azArg[0], "scanstats", n)==0 ){
    if( nArg==2 ){
      p->scanstatsOn = booleanValue(azArg[1]);
#ifndef SQLITE_ENABLE_STMT_SCANSTATUS
      raw_printf(stderr, "Warning: .scanstats not available in this build.\n");
#endif
................................................................................
          utf8_printf(stderr,"Error: %s\n", zErrMsg);
          if( bail_on_error ) return rc!=0 ? rc : 1;
        }else if( rc!=0 ){
          utf8_printf(stderr,"Error: unable to process SQL \"%s\"\n", z);
          if( bail_on_error ) return rc;
        }
      }

    }else if( strcmp(z, "-recommend") ){
      data.bRecommend = 1;
    }else{
      utf8_printf(stderr,"%s: Error: unknown option: %s\n", Argv0, z);
      raw_printf(stderr,"Use -help for a list of options.\n");
      return 1;
    }
  }

/*
** 2016 February 10
**
** 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.
**
*************************************************************************
*/

typedef sqlite3_int64 i64;

typedef struct IdxConstraint IdxConstraint;
typedef struct IdxContext IdxContext;
typedef struct IdxScan IdxScan;
typedef struct IdxWhere IdxWhere;

/*
** A single constraint. Equivalent to either "col = ?" or "col < ?".
**
** pLink:
**   ... todo ...
*/
struct IdxConstraint {
  char *zColl;                    /* Collation sequence */
  int bRange;                     /* True for range, false for eq */
  int iCol;                       /* Constrained table column */
  i64 depmask;                    /* Dependency mask */
  IdxConstraint *pNext;           /* Next constraint in pEq or pRange list */
  IdxConstraint *pLink;           /* See above */
};

/*
** A WHERE clause. Made up of IdxConstraint objects.
**
**   a=? AND b=? AND (c=? OR d=?) AND (e=? OR f=?)
**
*/
struct IdxWhere {
  IdxConstraint *pEq;             /* List of == constraints */
  IdxConstraint *pRange;          /* List of < constraints */
  IdxWhere **apOr;                /* Array of OR branches (joined by pNextOr) */
  IdxWhere *pNextOr;              /* Next in OR'd terms */
  IdxWhere *pParent;              /* Parent object (or NULL) */
};

/*
** A single scan of a single table.
*/
struct IdxScan {
  char *zTable;                   /* Name of table to scan */
  int iDb;                        /* Database containing table zTable */
  i64 covering;                   /* Mask of columns required for cov. index */
  IdxConstraint *pOrder;          /* ORDER BY columns */
  IdxWhere where;                 /* WHERE Constraints */
  IdxScan *pNextScan;             /* Next IdxScan object for same query */
};

/*
** Context object passed to idxWhereInfo()
*/
struct IdxContext {
  IdxWhere *pCurrent;             /* Current where clause */
  IdxScan *pScan;                 /* List of scan objects */
  sqlite3 *dbm;                   /* In-memory db for this analysis */
  int rc;                         /* Error code (if error has occurred) */
};

typedef struct PragmaTable PragmaTable;
typedef struct PragmaCursor PragmaCursor;

struct PragmaTable {
  sqlite3_vtab base;
  sqlite3 *db;
};

struct PragmaCursor {
  sqlite3_vtab_cursor base;
  sqlite3_stmt *pStmt;
  i64 iRowid;
};

/*
** Connect to or create a pragma virtual table.
*/
static int pragmaConnect(
  sqlite3 *db,
  void *pAux,
  int argc, const char *const*argv,
  sqlite3_vtab **ppVtab,
  char **pzErr
){
  const char *zSchema = 
    "CREATE TABLE a(tbl HIDDEN, cid, name, type, notnull, dflt_value, pk)";
  PragmaTable *pTab = 0;
  int rc = SQLITE_OK;

  rc = sqlite3_declare_vtab(db, zSchema);
  if( rc==SQLITE_OK ){
    pTab = (PragmaTable *)sqlite3_malloc64(sizeof(PragmaTable));
    if( pTab==0 ) rc = SQLITE_NOMEM;
  }

  assert( rc==SQLITE_OK || pTab==0 );
  if( rc==SQLITE_OK ){
    memset(pTab, 0, sizeof(PragmaTable));
    pTab->db = db;
  }

  *ppVtab = (sqlite3_vtab*)pTab;
  return rc;
}

/*
** Disconnect from or destroy a pragma virtual table.
*/
static int pragmaDisconnect(sqlite3_vtab *pVtab){
  sqlite3_free(pVtab);
  return SQLITE_OK;
}

/*
** xBestIndex method for pragma virtual tables.
*/
static int pragmaBestIndex(sqlite3_vtab *tab, sqlite3_index_info *pIdxInfo){
  int i;

  pIdxInfo->estimatedCost = 1.0e6;  /* Initial cost estimate */

  /* Look for a valid tbl=? constraint. */
  for(i=0; i<pIdxInfo->nConstraint; i++){
    if( pIdxInfo->aConstraint[i].usable==0 ) continue;
    if( pIdxInfo->aConstraint[i].op!=SQLITE_INDEX_CONSTRAINT_EQ ) continue;
    if( pIdxInfo->aConstraint[i].iColumn!=0 ) continue;
    pIdxInfo->idxNum = 1;
    pIdxInfo->estimatedCost = 1.0;
    pIdxInfo->aConstraintUsage[i].argvIndex = 1;
    pIdxInfo->aConstraintUsage[i].omit = 1;
    break;
  }
  if( i==pIdxInfo->nConstraint ){
    tab->zErrMsg = sqlite3_mprintf("missing required tbl=? constraint");
    return SQLITE_ERROR;
  }
  return SQLITE_OK;
}

/*
** Open a new pragma cursor.
*/
static int pragmaOpen(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor){
  PragmaTable *pTab = (PragmaTable *)pVTab;
  PragmaCursor *pCsr;

  pCsr = (PragmaCursor*)sqlite3_malloc64(sizeof(PragmaCursor));
  if( pCsr==0 ){
    return SQLITE_NOMEM;
  }else{
    memset(pCsr, 0, sizeof(PragmaCursor));
    pCsr->base.pVtab = pVTab;
  }

  *ppCursor = (sqlite3_vtab_cursor*)pCsr;
  return SQLITE_OK;
}

/*
** Move a statvfs cursor to the next entry in the file.
*/
static int pragmaNext(sqlite3_vtab_cursor *pCursor){
  PragmaCursor *pCsr = (PragmaCursor*)pCursor;
  int rc = SQLITE_OK;

  if( sqlite3_step(pCsr->pStmt)!=SQLITE_ROW ){
    rc = sqlite3_finalize(pCsr->pStmt);
    pCsr->pStmt = 0;
  }
  pCsr->iRowid++;
  return rc;
}

static int pragmaEof(sqlite3_vtab_cursor *pCursor){
  PragmaCursor *pCsr = (PragmaCursor*)pCursor;
  return pCsr->pStmt==0;
}

static int pragmaFilter(
  sqlite3_vtab_cursor *pCursor, 
  int idxNum, const char *idxStr,
  int argc, sqlite3_value **argv
){
  PragmaCursor *pCsr = (PragmaCursor*)pCursor;
  PragmaTable *pTab = (PragmaTable*)(pCursor->pVtab);
  char *zSql;
  const char *zTbl;
  int rc = SQLITE_OK;

  if( pCsr->pStmt ){
    sqlite3_finalize(pCsr->pStmt);
    pCsr->pStmt = 0;
  }
  pCsr->iRowid = 0;

  assert( argc==1 );
  zTbl = (const char*)sqlite3_value_text(argv[0]);
  zSql = sqlite3_mprintf("PRAGMA table_info(%Q)", zTbl);
  if( zSql==0 ){
    rc = SQLITE_NOMEM;
  }else{
    rc = sqlite3_prepare_v2(pTab->db, zSql, -1, &pCsr->pStmt, 0);
  }
  return pragmaNext(pCursor);;
}

/*
** xColumn method.
*/
static int pragmaColumn(
  sqlite3_vtab_cursor *pCursor, 
  sqlite3_context *ctx, 
  int iCol
){
  PragmaCursor *pCsr = (PragmaCursor *)pCursor;
  if( iCol>0 ){
    sqlite3_result_value(ctx, sqlite3_column_value(pCsr->pStmt, iCol-1));
  }
  return SQLITE_OK;
}

static int pragmaRowid(sqlite3_vtab_cursor *pCursor, sqlite_int64 *pRowid){
  PragmaCursor *pCsr = (PragmaCursor *)pCursor;
  *pRowid = pCsr->iRowid;
  return SQLITE_OK;
}

static int registerPragmaVtabs(sqlite3 *db){
  static sqlite3_module pragma_module = {
    0,                            /* iVersion */
    pragmaConnect,                /* xCreate */
    pragmaConnect,                /* xConnect */
    pragmaBestIndex,              /* xBestIndex */
    pragmaDisconnect,             /* xDisconnect */
    pragmaDisconnect,             /* xDestroy */
    pragmaOpen,                   /* xOpen - open a cursor */
    pragmaClose,                  /* xClose - close a cursor */
    pragmaFilter,                 /* xFilter - configure scan constraints */
    pragmaNext,                   /* xNext - advance a cursor */
    pragmaEof,                    /* xEof - check for end of scan */
    pragmaColumn,                 /* xColumn - read data */
    pragmaRowid,                  /* xRowid - read data */
    0,                            /* xUpdate */
    0,                            /* xBegin */
    0,                            /* xSync */
    0,                            /* xCommit */
    0,                            /* xRollback */
    0,                            /* xFindMethod */
    0,                            /* xRename */
  };
  return sqlite3_create_module(db, "pragma_table_info", &pragma_module, 0);
}

/*
** Allocate and return nByte bytes of zeroed memory using sqlite3_malloc(). 
** If the allocation fails, set *pRc to SQLITE_NOMEM and return NULL.
*/
static void *idxMalloc(int *pRc, int nByte){
  void *pRet;
  assert( *pRc==SQLITE_OK );
  assert( nByte>0 );
  pRet = sqlite3_malloc(nByte);
  if( pRet ){
    memset(pRet, 0, nByte);
  }else{
    *pRc = SQLITE_NOMEM;
  }
  return pRet;
}

/*
** Allocate and return a new IdxConstraint object. Set the IdxConstraint.zColl
** variable to point to a copy of nul-terminated string zColl.
*/
static IdxConstraint *idxNewConstraint(int *pRc, const char *zColl){
  IdxConstraint *pNew;
  int nColl = strlen(zColl);

  assert( *pRc==SQLITE_OK );
  pNew = (IdxConstraint*)idxMalloc(pRc, sizeof(IdxConstraint) * nColl + 1);
  if( pNew ){
    pNew->zColl = (char*)&pNew[1];
    memcpy(pNew->zColl, zColl, nColl+1);
  }
  return pNew;
}

/*
** SQLITE_DBCONFIG_WHEREINFO callback.
*/
static void idxWhereInfo(
  void *pCtx,                     /* Pointer to IdxContext structure */
  int eOp, 
  const char *zVal, 
  int iVal, 
  i64 mask
){
  IdxContext *p = (IdxContext*)pCtx;

#if 1
  const char *zOp = 
    eOp==SQLITE_WHEREINFO_TABLE ? "TABLE" :
    eOp==SQLITE_WHEREINFO_EQUALS ? "EQUALS" :
    eOp==SQLITE_WHEREINFO_RANGE ? "RANGE" :
    eOp==SQLITE_WHEREINFO_ORDERBY ? "ORDERBY" :
    eOp==SQLITE_WHEREINFO_NEXTOR ? "NEXTOR" :
    eOp==SQLITE_WHEREINFO_ENDOR ? "ENDOR" :
    eOp==SQLITE_WHEREINFO_BEGINOR ? "BEGINOR" :
    "!error!";
  printf("op=%s zVal=%s iVal=%d mask=%llx\n", zOp, zVal, iVal, mask);
#endif

  if( p->rc==SQLITE_OK ){
    assert( eOp==SQLITE_WHEREINFO_TABLE || p->pScan!=0 );
    switch( eOp ){
      case SQLITE_WHEREINFO_TABLE: {
        int nVal = strlen(zVal);
        IdxScan *pNew = (IdxScan*)idxMalloc(&p->rc, sizeof(IdxScan) + nVal + 1);
        if( !pNew ) return;
        pNew->zTable = (char*)&pNew[1];
        memcpy(pNew->zTable, zVal, nVal+1);
        pNew->pNextScan = p->pScan;
        pNew->covering = mask;
        p->pScan = pNew;
        p->pCurrent = &pNew->where;
        break;
      }

      case SQLITE_WHEREINFO_ORDERBY: {
        IdxConstraint *pNew = idxNewConstraint(&p->rc, zVal);
        IdxConstraint **pp;
        if( pNew==0 ) return;
        pNew->iCol = iVal;
        for(pp=&p->pScan->pOrder; *pp; pp=&(*pp)->pNext);
        *pp = pNew;
        break;
      }

      case SQLITE_WHEREINFO_EQUALS:
      case SQLITE_WHEREINFO_RANGE: {
        IdxConstraint *pNew = idxNewConstraint(&p->rc, zVal);
        if( pNew==0 ) return;
        pNew->iCol = iVal;
        pNew->depmask = mask;

        if( eOp==SQLITE_WHEREINFO_RANGE ){
          pNew->pNext = p->pCurrent->pRange;
          p->pCurrent->pRange = pNew;
        }else{
          pNew->pNext = p->pCurrent->pEq;
          p->pCurrent->pEq = pNew;
        }
        break;
      }

      case SQLITE_WHEREINFO_BEGINOR: {
        assert( 0 );
        break;
      }
      case SQLITE_WHEREINFO_ENDOR: {
        assert( 0 );
        break;
      }
      case SQLITE_WHEREINFO_NEXTOR: {
        assert( 0 );
        break;
      }
    }
  }
}

/*
** An error associated with database handle db has just occurred. Pass
** the error message to callback function xOut.
*/
static void idxDatabaseError(
  sqlite3 *db,                    /* Database handle */
  char **pzErrmsg                 /* Write error here */
){
  *pzErrmsg = sqlite3_mprintf("%s", sqlite3_errmsg(db));
}

static int idxCreateTables(sqlite3 *db, sqlite3 *dbm, IdxScan *pScan){
  int rc = SQLITE_OK;
  IdxScan *pIter;
  for(pIter=pScan; pIter; pIter=pIter->pNextScan){
  }
}

static void idxScanFree(IdxScan *pScan){
}

/*
** The xOut callback is invoked to return command output to the user. The
** second argument is always a nul-terminated string. The first argument is
** passed zero if the string contains normal output or non-zero if it is an
** error message.
*/
int shellIndexesCommand(
  sqlite3 *db,                         /* Database handle */
  const char *zSql,                    /* SQL to find indexes for */
  void (*xOut)(void*, const char*),    /* Output callback */
  void *pOutCtx,                       /* Context for xOut() */
  char **pzErrmsg                      /* OUT: Error message (sqlite3_malloc) */
){
  int rc = SQLITE_OK;
  sqlite3 *dbm = 0;
  IdxContext ctx;
  sqlite3_stmt *pStmt = 0;        /* Statement compiled from zSql */

  memset(&ctx, 0, sizeof(IdxContext));

  /* Open an in-memory database to work with. The main in-memory 
  ** database schema contains tables similar to those in the users 
  ** database (handle db). The attached in-memory db (aux) contains
  ** application tables used by the code in this file.  */
  rc = sqlite3_open(":memory:", &dbm);
  if( rc==SQLITE_OK ){
    rc = sqlite3_exec(dbm, 
        "ATTACH ':memory:' AS aux;"
        "CREATE TABLE aux.depmask(mask PRIMARY KEY) WITHOUT ROWID;"
        , 0, 0, 0
    );
  }
  if( rc!=SQLITE_OK ){
    idxDatabaseError(dbm, pzErrmsg);
    goto indexes_out;
  }

  /* Analyze the SELECT statement in zSql. */
  ctx.dbm = dbm;
  sqlite3_db_config(db, SQLITE_DBCONFIG_WHEREINFO, idxWhereInfo, (void*)&ctx);
  rc = sqlite3_prepare(db, zSql, -1, &pStmt, 0);
  sqlite3_db_config(db, SQLITE_DBCONFIG_WHEREINFO, (void*)0, (void*)0);
  if( rc!=SQLITE_OK ){
    idxDatabaseError(db, pzErrmsg);
    goto indexes_out;
  }

  /* Create tables within the main in-memory database. These tables
  ** have the same names, columns and declared types as the tables in
  ** the user database. All constraints except for PRIMARY KEY are
  ** removed. */
  rc = idxCreateTables(db, dbm, ctx.pScan);
  if( rc!=SQLITE_OK ){
    goto indexes_out;
  }

  /* Create candidate indexes within the in-memory database file */

 indexes_out:
  idxScanFree(ctx.pScan);
  sqlite3_close(dbm);
  return rc;
}

** which case the trigger setting is not reported back. </dd>
**
** </dl>
*/
#define SQLITE_DBCONFIG_LOOKASIDE       1001  /* void* int int */
#define SQLITE_DBCONFIG_ENABLE_FKEY     1002  /* int int* */
#define SQLITE_DBCONFIG_ENABLE_TRIGGER  1003  /* int int* */











/*
** CAPI3REF: Enable Or Disable Extended Result Codes
** METHOD: sqlite3
**
** ^The sqlite3_extended_result_codes() routine enables or disables the

** which case the trigger setting is not reported back. </dd>
**
** </dl>
*/
#define SQLITE_DBCONFIG_LOOKASIDE       1001  /* void* int int */
#define SQLITE_DBCONFIG_ENABLE_FKEY     1002  /* int int* */
#define SQLITE_DBCONFIG_ENABLE_TRIGGER  1003  /* int int* */
#define SQLITE_DBCONFIG_WHEREINFO       1004  /* xWhereInfo void* */

#define SQLITE_WHEREINFO_TABLE   1
#define SQLITE_WHEREINFO_EQUALS  2
#define SQLITE_WHEREINFO_RANGE   3
#define SQLITE_WHEREINFO_ORDERBY 4
#define SQLITE_WHEREINFO_BEGINOR 5
#define SQLITE_WHEREINFO_ENDOR   6
#define SQLITE_WHEREINFO_NEXTOR  7


/*
** CAPI3REF: Enable Or Disable Extended Result Codes
** METHOD: sqlite3
**
** ^The sqlite3_extended_result_codes() routine enables or disables the

  sqlite3 *pUnlockConnection;           /* Connection to watch for unlock */
  void *pUnlockArg;                     /* Argument to xUnlockNotify */
  void (*xUnlockNotify)(void **, int);  /* Unlock notify callback */
  sqlite3 *pNextBlocked;        /* Next in list of all blocked connections */
#endif
#ifdef SQLITE_USER_AUTHENTICATION
  sqlite3_userauth auth;        /* User authentication information */




#endif
};

/*
** A macro to discover the encoding of a database.
*/
#define SCHEMA_ENC(db) ((db)->aDb[0].pSchema->enc)

  sqlite3 *pUnlockConnection;           /* Connection to watch for unlock */
  void *pUnlockArg;                     /* Argument to xUnlockNotify */
  void (*xUnlockNotify)(void **, int);  /* Unlock notify callback */
  sqlite3 *pNextBlocked;        /* Next in list of all blocked connections */
#endif
#ifdef SQLITE_USER_AUTHENTICATION
  sqlite3_userauth auth;        /* User authentication information */
#endif
#ifdef SQLITE_SCHEMA_LINT
  void (*xWhereInfo)(void*, int, const char*, int, i64);
  void *pWhereInfoCtx;
#endif
};

/*
** A macro to discover the encoding of a database.
*/
#define SCHEMA_ENC(db) ((db)->aDb[0].pSchema->enc)

#endif
    return 1;
  }
  return 0;
}

#ifdef SQLITE_SCHEMA_LINT
static char *whereAppendPrintf(sqlite3 *db, const char *zFmt, ...){
  va_list ap;
  char *zRes = 0;
  va_start(ap, zFmt);
  zRes = sqlite3_vmprintf(zFmt, ap);
  if( zRes==0 ){
    db->mallocFailed = 1;
  }else if( db->mallocFailed ){
    sqlite3_free(zRes);
    zRes = 0;
  }
  va_end(ap);
  return zRes;
}

/*
** Append a representation of term pTerm to the string in zIn and return
** the result. Or, if an OOM occurs, free zIn and return a NULL pointer.
*/
static char *whereAppendSingleTerm(
  Parse *pParse,
  Table *pTab,
  int iCol,
  int bOr,
  char *zIn,
  WhereTerm *pTerm
){
  char *zBuf;
  sqlite3 *db = pParse->db;
  Expr *pX = pTerm->pExpr;
  CollSeq *pColl;
  const char *zOp = 0;

  if( pTerm->eOperator & (WO_IS|WO_EQ|WO_IN) ){
    zOp = "eq";
  }else if( pTerm->eOperator & (WO_LT|WO_LE|WO_GE|WO_GT) ){
    zOp = "range";
  }
  pColl = sqlite3BinaryCompareCollSeq(pParse, pX->pLeft, pX->pRight);

  if( zOp ){
    const char *zFmt = bOr ? "%z{{%s \"%w\" \"%w\" %lld}}" :
                             "%z{%s \"%w\" \"%w\" %lld}";
    zBuf = whereAppendPrintf(db, zFmt, zIn, 
        zOp, pTab->aCol[iCol].zName, 
        (pColl ? pColl->zName : "BINARY"),
        pTerm->prereqRight
    );
  }else{
    zBuf = zIn;
  }

  return zBuf;
}

static char *whereTraceWC(
  Parse *pParse, 
  int bInitialSpace,
  struct SrcList_item *pItem,
  char *zIn,
  WhereClause *pWC

){
  sqlite3 *db = pParse->db;
  Table *pTab = pItem->pTab;
  char *zBuf = zIn;
  int iCol;

  int ii;
  int bFirst = !bInitialSpace;
  int bOr = (pWC->op==TK_OR);

  /* List of WO_SINGLE constraints */
  for(iCol=0; iCol<pTab->nCol; iCol++){
    int opMask = WO_SINGLE; 
    WhereScan scan;
    WhereTerm *pTerm;
    for(pTerm=whereScanInit(&scan, pWC, pItem->iCursor, iCol, opMask, 0);
        pTerm;
        pTerm=whereScanNext(&scan)
    ){
      /* assert( iCol==pTerm->u.leftColumn ); */
      if( bFirst==0 ) zBuf = whereAppendPrintf(db, "%z ", zBuf);
      zBuf = whereAppendSingleTerm(pParse, pTab, iCol, bOr, zBuf, pTerm);







      bFirst = 0;
    }
  }

  /* Add composite - (WO_OR|WO_AND) - constraints */
  for(ii=0; ii<pWC->nTerm; ii++){
    WhereTerm *pTerm = &pWC->a[ii];
    if( pTerm->eOperator & (WO_OR|WO_AND) ){
      const char *zFmt = ((pTerm->eOperator&WO_OR) ? "%z%s{or " : "%z%s{");
      zBuf = whereAppendPrintf(db, zFmt, zBuf, bFirst ? "" : " ");
      zBuf = whereTraceWC(pParse, 0, pItem, zBuf, &pTerm->u.pOrInfo->wc);
      zBuf = whereAppendPrintf(db, "%z}", zBuf);








      bFirst = 0;
    }
  }

  return zBuf;
}

static void whereTraceBuilder(
  Parse *pParse,
  WhereLoopBuilder *p
){
  sqlite3 *db = pParse->db;
  if( db->xTrace ){
    ExprList *pOrderBy = p->pOrderBy;
    WhereInfo *pWInfo = p->pWInfo;
    int nTablist = pWInfo->pTabList->nSrc;
    int ii;


    /* Loop through each element of the FROM clause. Ignore any sub-selects
    ** or views. Invoke the xTrace() callback once for each real table. */
    for(ii=0; ii<nTablist; ii++){
      char *zBuf = 0;
      int iCol;
      int nCol;
      Table *pTab;

      struct SrcList_item *pItem = &pWInfo->pTabList->a[ii];
      if( pItem->pSelect ) continue;
      pTab = pItem->pTab;
      nCol = pTab->nCol;


      /* Append the table name to the buffer. */
      zBuf = whereAppendPrintf(db, "\"%w\"", pTab->zName);



      /* Append the list of columns required to create a covering index */
      zBuf = whereAppendPrintf(db, "%z {cols", zBuf);
      if( 0==(pItem->colUsed & ((u64)1 << (sizeof(Bitmask)*8-1))) ){
        for(iCol=0; iCol<nCol; iCol++){
          if( iCol==(sizeof(Bitmask)*8-1) ) break;
          if( pItem->colUsed & ((u64)1 << iCol) ){
            const char *zName = pTab->aCol[iCol].zName;
            zBuf = whereAppendPrintf(db, "%z \"%w\"", zBuf, zName);
          }
        }
      }
      zBuf = whereAppendPrintf(db, "%z}",zBuf);

      /* Append the contents of WHERE clause */
      zBuf = whereTraceWC(pParse, 1, pItem, zBuf, p->pWC);

      /* Append the ORDER BY clause, if any */

      if( pOrderBy ){
        int i;
        int bFirst = 1;
        for(i=0; i<pOrderBy->nExpr; i++){
          Expr *pExpr = pOrderBy->a[i].pExpr; 
          CollSeq *pColl = sqlite3ExprCollSeq(pParse, pExpr);

          pExpr = sqlite3ExprSkipCollate(pExpr);
          if( pExpr->op==TK_COLUMN && pExpr->iTable==pItem->iCursor ){
            if( pExpr->iColumn>=0 ){
              const char *zName = pTab->aCol[pExpr->iColumn].zName;
              zBuf = whereAppendPrintf(db, "%z%s\"%w\" \"%w\" %s", zBuf,
                  bFirst ? " {orderby " : " ", zName, pColl->zName,
                  (pOrderBy->a[i].sortOrder ? "DESC" : "ASC")
              );
              bFirst = 0;


            }
          }
        }
        if( bFirst==0 ) zBuf = whereAppendPrintf(db, "%z}", zBuf);
      }

      /* Pass the buffer to the xTrace() callback, then free it */
      db->xTrace(db->pTraceArg, zBuf);
      sqlite3DbFree(db, zBuf);



    }
  }
}
#else
# define whereTraceBuilder(x,y)
#endif

#endif
    return 1;
  }
  return 0;
}

#ifdef SQLITE_SCHEMA_LINT























































static void whereTraceWC(
  Parse *pParse, 

  struct SrcList_item *pItem,

  WhereClause *pWC,
  int bOr
){
  sqlite3 *db = pParse->db;
  Table *pTab = pItem->pTab;
  void (*x)(void*, int, const char*, int, i64) = db->xWhereInfo;
  void *pCtx = db->pWhereInfoCtx;
  int bFirst = 1;                 /* True until first callback is made */
  int ii;



  /* Issue callbacks for WO_SINGLE constraints */
  for(ii=0; ii<pTab->nCol; ii++){
    int opMask = WO_SINGLE; 
    WhereScan scan;
    WhereTerm *pTerm;
    for(pTerm=whereScanInit(&scan, pWC, pItem->iCursor, ii, opMask, 0);
        pTerm;
        pTerm=whereScanNext(&scan)
    ){
      int eOp;
      Expr *pX = pTerm->pExpr;
      CollSeq *pC = sqlite3BinaryCompareCollSeq(pParse, pX->pLeft, pX->pRight);
      if( pTerm->eOperator & (WO_IS|WO_EQ|WO_IN) ){
        eOp = SQLITE_WHEREINFO_EQUALS;
      }else{
        eOp = SQLITE_WHEREINFO_RANGE;
      }
      if( bOr && !bFirst ) x(pCtx, SQLITE_WHEREINFO_NEXTOR, 0, 0, 0);
      x(pCtx, eOp, (pC ? pC->zName : "BINARY"), ii, pTerm->prereqRight);
      bFirst = 0;
    }
  }

  /* Callbacks for composite - (WO_OR|WO_AND) - constraints */
  for(ii=0; ii<pWC->nTerm; ii++){
    WhereTerm *pTerm = &pWC->a[ii];
    if( pTerm->eOperator & WO_OR ){




      assert( bOr==0 );
      x(pCtx, SQLITE_WHEREINFO_BEGINOR, 0, 0, 0);
      whereTraceWC(pParse, pItem, &pTerm->u.pOrInfo->wc, 1);
      x(pCtx, SQLITE_WHEREINFO_ENDOR, 0, 0, 0);
    }
    if( pTerm->eOperator & WO_AND ){
      if( bOr && !bFirst ) x(pCtx, SQLITE_WHEREINFO_NEXTOR, 0, 0, 0);
      whereTraceWC(pParse, pItem, &pTerm->u.pAndInfo->wc, 0);
      bFirst = 0;
    }
  }
}



static void whereTraceBuilder(
  Parse *pParse,
  WhereLoopBuilder *p
){
  sqlite3 *db = pParse->db;
  if( db->xWhereInfo && db->init.busy==0 ){
    void (*x)(void*, int, const char*, int, i64) = db->xWhereInfo;
    void *pCtx = db->pWhereInfoCtx;

    int ii;
    int nTab = p->pWInfo->pTabList->nSrc;

    /* Loop through each element of the FROM clause. Ignore any sub-selects
    ** or views. Invoke the xWhereInfo() callback multiple times for each
    ** real table.  */
    for(ii=0; ii<p->pWInfo->pTabList->nSrc; ii++){




      struct SrcList_item *pItem = &p->pWInfo->pTabList->a[ii];
      if( pItem->pSelect==0 ){
        Table *pTab = pItem->pTab;

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



        /* Table name callback */
        x(pCtx, SQLITE_WHEREINFO_TABLE, pTab->zName, iDb, pItem->colUsed);


















        /* ORDER BY callbacks */
        if( p->pOrderBy ){
          int i;
          int bFirst = 1;
          for(i=0; i<p->pOrderBy->nExpr; i++){
            Expr *pExpr = p->pOrderBy->a[i].pExpr; 
            CollSeq *pColl = sqlite3ExprCollSeq(pParse, pExpr);

            pExpr = sqlite3ExprSkipCollate(pExpr);
            if( pExpr->op==TK_COLUMN && pExpr->iTable==pItem->iCursor ){
              int iCol = pExpr->iColumn;






              if( iCol>=0 ){
                x(pCtx, SQLITE_WHEREINFO_ORDERBY, pColl->zName, iCol, 0); 
              }
            }
          }

        }




        /* WHERE callbacks */
        whereTraceWC(pParse, pItem, p->pWC, 0);
      }
    }
  }
}
#else
# define whereTraceBuilder(x,y)
#endif