/ Check-in [37ae5f5e]
Login

Many hyperlinks are disabled.
Use anonymous login to enable hyperlinks.

Overview
Comment:Reorganize and cleanup the prepared statement object. Remove code that has been commented out for ages and is no longer relevant to anything. (CVS 6786)
Downloads: Tarball | ZIP archive | SQL archive
Timelines: family | ancestors | descendants | both | trunk
Files: files | file ages | folders
SHA1:37ae5f5e8feb34a8e6e8b34aa18df1e9a1ce55cb
User & Date: drh 2009-06-19 14:06:03
Context
2009-06-19
16:44
Make sure group_concat() ignores initial NULL values. (CVS 6787) check-in: 90c3b23c user: drh tags: trunk
14:06
Reorganize and cleanup the prepared statement object. Remove code that has been commented out for ages and is no longer relevant to anything. (CVS 6786) check-in: 37ae5f5e user: drh tags: trunk
02:25
Fix a possible segfault when backing up an encrypted database. (CVS 6785) check-in: 7d8f178c user: drh tags: trunk
Changes
Hide Diffs Unified Diffs Ignore Whitespace Patch

Changes to src/func.c.

12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
....
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
** This file contains the C functions that implement various SQL
** functions of SQLite.  
**
** There is only one exported symbol in this file - the function
** sqliteRegisterBuildinFunctions() found at the bottom of the file.
** All other code has file scope.
**
** $Id: func.c,v 1.237 2009/06/03 01:24:54 drh Exp $
*/
#include "sqliteInt.h"
#include <stdlib.h>
#include <assert.h>
#include "vdbeInt.h"

/*
................................................................................
  if( !db->mallocFailed ){
    int rc = sqlite3_overload_function(db, "MATCH", 2);
    assert( rc==SQLITE_NOMEM || rc==SQLITE_OK );
    if( rc==SQLITE_NOMEM ){
      db->mallocFailed = 1;
    }
  }
#ifdef SQLITE_SSE
  (void)sqlite3SseFunctions(db);
#endif
}

/*
** Set the LIKEOPT flag on the 2-argument function with the given name.
*/
static void setLikeOptFlag(sqlite3 *db, const char *zName, u8 flagVal){
  FuncDef *pDef;







|







 







<
<
<







12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
....
1315
1316
1317
1318
1319
1320
1321



1322
1323
1324
1325
1326
1327
1328
** This file contains the C functions that implement various SQL
** functions of SQLite.  
**
** There is only one exported symbol in this file - the function
** sqliteRegisterBuildinFunctions() found at the bottom of the file.
** All other code has file scope.
**
** $Id: func.c,v 1.238 2009/06/19 14:06:03 drh Exp $
*/
#include "sqliteInt.h"
#include <stdlib.h>
#include <assert.h>
#include "vdbeInt.h"

/*
................................................................................
  if( !db->mallocFailed ){
    int rc = sqlite3_overload_function(db, "MATCH", 2);
    assert( rc==SQLITE_NOMEM || rc==SQLITE_OK );
    if( rc==SQLITE_NOMEM ){
      db->mallocFailed = 1;
    }
  }



}

/*
** Set the LIKEOPT flag on the 2-argument function with the given name.
*/
static void setLikeOptFlag(sqlite3 *db, const char *zName, u8 flagVal){
  FuncDef *pDef;

Changes to src/main.c.

10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
...
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
**
*************************************************************************
** Main file for the SQLite library.  The routines in this file
** implement the programmer interface to the library.  Routines in
** other files are for internal use by SQLite and should not be
** accessed by users of the library.
**
** $Id: main.c,v 1.557 2009/06/09 19:53:58 drh Exp $
*/
#include "sqliteInt.h"

#ifdef SQLITE_ENABLE_FTS3
# include "fts3.h"
#endif
#ifdef SQLITE_ENABLE_RTREE
................................................................................
    return SQLITE_OK;
  }
  if( !sqlite3SafetyCheckSickOrOk(db) ){
    return SQLITE_MISUSE;
  }
  sqlite3_mutex_enter(db->mutex);

#ifdef SQLITE_SSE
  {
    extern void sqlite3SseCleanup(sqlite3*);
    sqlite3SseCleanup(db);
  }
#endif 

  sqlite3ResetInternalSchema(db, 0);

  /* If a transaction is open, the ResetInternalSchema() call above
  ** will not have called the xDisconnect() method on any virtual
  ** tables in the db->aVTrans[] array. The following sqlite3VtabRollback()
  ** call will do so. We need to do this before the check for active
  ** SQL statements below, as the v-table implementation may be storing







|







 







<
<
<
<
<
<
<







10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
...
579
580
581
582
583
584
585







586
587
588
589
590
591
592
**
*************************************************************************
** Main file for the SQLite library.  The routines in this file
** implement the programmer interface to the library.  Routines in
** other files are for internal use by SQLite and should not be
** accessed by users of the library.
**
** $Id: main.c,v 1.558 2009/06/19 14:06:03 drh Exp $
*/
#include "sqliteInt.h"

#ifdef SQLITE_ENABLE_FTS3
# include "fts3.h"
#endif
#ifdef SQLITE_ENABLE_RTREE
................................................................................
    return SQLITE_OK;
  }
  if( !sqlite3SafetyCheckSickOrOk(db) ){
    return SQLITE_MISUSE;
  }
  sqlite3_mutex_enter(db->mutex);








  sqlite3ResetInternalSchema(db, 0);

  /* If a transaction is open, the ResetInternalSchema() call above
  ** will not have called the xDisconnect() method on any virtual
  ** tables in the db->aVTrans[] array. The following sqlite3VtabRollback()
  ** call will do so. We need to do this before the check for active
  ** SQL statements below, as the v-table implementation may be storing

Changes to src/parse.y.

10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
....
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
....
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
**
*************************************************************************
** This file contains SQLite's grammar for SQL.  Process this file
** using the lemon parser generator to generate C code that runs
** the parser.  Lemon will also generate a header file containing
** numeric codes for all of the tokens.
**
** @(#) $Id: parse.y,v 1.282 2009/06/12 13:53:52 drh Exp $
*/

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

// The type of the data attached to each token is Token.  This is also the
// default type for non-terminals.
................................................................................
cmd ::= VACUUM.                {sqlite3Vacuum(pParse);}
cmd ::= VACUUM nm.             {sqlite3Vacuum(pParse);}
%endif  SQLITE_OMIT_ATTACH
%endif  SQLITE_OMIT_VACUUM

///////////////////////////// The PRAGMA command /////////////////////////////
//
%ifndef SQLITE_OMIT_PARSER
%ifndef SQLITE_OMIT_PRAGMA
cmd ::= PRAGMA nm(X) dbnm(Z).                {sqlite3Pragma(pParse,&X,&Z,0,0);}
cmd ::= PRAGMA nm(X) dbnm(Z) EQ nmnum(Y).    {sqlite3Pragma(pParse,&X,&Z,&Y,0);}
cmd ::= PRAGMA nm(X) dbnm(Z) LP nmnum(Y) RP. {sqlite3Pragma(pParse,&X,&Z,&Y,0);}
cmd ::= PRAGMA nm(X) dbnm(Z) EQ minus_num(Y). 
                                             {sqlite3Pragma(pParse,&X,&Z,&Y,1);}
cmd ::= PRAGMA nm(X) dbnm(Z) LP minus_num(Y) RP.
................................................................................

nmnum(A) ::= plus_num(X).             {A = X;}
nmnum(A) ::= nm(X).                   {A = X;}
nmnum(A) ::= ON(X).                   {A = X;}
nmnum(A) ::= DELETE(X).               {A = X;}
nmnum(A) ::= DEFAULT(X).              {A = X;}
%endif SQLITE_OMIT_PRAGMA
%endif SQLITE_OMIT_PARSER
plus_num(A) ::= plus_opt number(X).   {A = X;}
minus_num(A) ::= MINUS number(X).     {A = X;}
number(A) ::= INTEGER|FLOAT(X).       {A = X;}
plus_opt ::= PLUS.
plus_opt ::= .

//////////////////////////// The CREATE TRIGGER command /////////////////////







|







 







<







 







<







10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
....
1104
1105
1106
1107
1108
1109
1110

1111
1112
1113
1114
1115
1116
1117
....
1119
1120
1121
1122
1123
1124
1125

1126
1127
1128
1129
1130
1131
1132
**
*************************************************************************
** This file contains SQLite's grammar for SQL.  Process this file
** using the lemon parser generator to generate C code that runs
** the parser.  Lemon will also generate a header file containing
** numeric codes for all of the tokens.
**
** @(#) $Id: parse.y,v 1.283 2009/06/19 14:06:03 drh Exp $
*/

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

// The type of the data attached to each token is Token.  This is also the
// default type for non-terminals.
................................................................................
cmd ::= VACUUM.                {sqlite3Vacuum(pParse);}
cmd ::= VACUUM nm.             {sqlite3Vacuum(pParse);}
%endif  SQLITE_OMIT_ATTACH
%endif  SQLITE_OMIT_VACUUM

///////////////////////////// The PRAGMA command /////////////////////////////
//

%ifndef SQLITE_OMIT_PRAGMA
cmd ::= PRAGMA nm(X) dbnm(Z).                {sqlite3Pragma(pParse,&X,&Z,0,0);}
cmd ::= PRAGMA nm(X) dbnm(Z) EQ nmnum(Y).    {sqlite3Pragma(pParse,&X,&Z,&Y,0);}
cmd ::= PRAGMA nm(X) dbnm(Z) LP nmnum(Y) RP. {sqlite3Pragma(pParse,&X,&Z,&Y,0);}
cmd ::= PRAGMA nm(X) dbnm(Z) EQ minus_num(Y). 
                                             {sqlite3Pragma(pParse,&X,&Z,&Y,1);}
cmd ::= PRAGMA nm(X) dbnm(Z) LP minus_num(Y) RP.
................................................................................

nmnum(A) ::= plus_num(X).             {A = X;}
nmnum(A) ::= nm(X).                   {A = X;}
nmnum(A) ::= ON(X).                   {A = X;}
nmnum(A) ::= DELETE(X).               {A = X;}
nmnum(A) ::= DEFAULT(X).              {A = X;}
%endif SQLITE_OMIT_PRAGMA

plus_num(A) ::= plus_opt number(X).   {A = X;}
minus_num(A) ::= MINUS number(X).     {A = X;}
number(A) ::= INTEGER|FLOAT(X).       {A = X;}
plus_opt ::= PLUS.
plus_opt ::= .

//////////////////////////// The CREATE TRIGGER command /////////////////////

Changes to src/pragma.c.

7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
....
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
....
1419
1420
1421
1422
1423
1424
1425
1426
**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains code used to implement the PRAGMA command.
**
** $Id: pragma.c,v 1.212 2009/06/03 11:25:07 danielk1977 Exp $
*/
#include "sqliteInt.h"

/* Ignore this whole file if pragmas are disabled
*/
#if !defined(SQLITE_OMIT_PRAGMA) && !defined(SQLITE_OMIT_PARSER)

/*
** Interpret the given string as a safety level.  Return 0 for OFF,
** 1 for ON or NORMAL and 2 for FULL.  Return 1 for an empty or 
** unrecognized string argument.
**
** Note that the values returned are one less that the values that
................................................................................
      sqlite3VdbeAddOp4(v, OP_String8, 0, 2, 0, zState, P4_STATIC);
      sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 2);
    }

  }else
#endif

#ifdef SQLITE_SSE
  /*
  ** Check to see if the sqlite_statements table exists.  Create it
  ** if it does not.
  */
  if( sqlite3StrICmp(zLeft, "create_sqlite_statement_table")==0 ){
    extern int sqlite3CreateStatementsTable(Parse*);
    sqlite3CreateStatementsTable(pParse);
  }else
#endif

#if SQLITE_HAS_CODEC
  if( sqlite3StrICmp(zLeft, "key")==0 && zRight ){
    sqlite3_key(db, zRight, sqlite3Strlen30(zRight));
  }else
  if( sqlite3StrICmp(zLeft, "rekey")==0 && zRight ){
    sqlite3_rekey(db, zRight, sqlite3Strlen30(zRight));
  }else
................................................................................
  }
#endif
pragma_out:
  sqlite3DbFree(db, zLeft);
  sqlite3DbFree(db, zRight);
}

#endif /* SQLITE_OMIT_PRAGMA || SQLITE_OMIT_PARSER */







|





|







 







<
<
<
<
<
<
<
<
<
<
<







 







|
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
....
1344
1345
1346
1347
1348
1349
1350











1351
1352
1353
1354
1355
1356
1357
....
1408
1409
1410
1411
1412
1413
1414
1415
**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains code used to implement the PRAGMA command.
**
** $Id: pragma.c,v 1.213 2009/06/19 14:06:03 drh Exp $
*/
#include "sqliteInt.h"

/* Ignore this whole file if pragmas are disabled
*/
#if !defined(SQLITE_OMIT_PRAGMA)

/*
** Interpret the given string as a safety level.  Return 0 for OFF,
** 1 for ON or NORMAL and 2 for FULL.  Return 1 for an empty or 
** unrecognized string argument.
**
** Note that the values returned are one less that the values that
................................................................................
      sqlite3VdbeAddOp4(v, OP_String8, 0, 2, 0, zState, P4_STATIC);
      sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 2);
    }

  }else
#endif












#if SQLITE_HAS_CODEC
  if( sqlite3StrICmp(zLeft, "key")==0 && zRight ){
    sqlite3_key(db, zRight, sqlite3Strlen30(zRight));
  }else
  if( sqlite3StrICmp(zLeft, "rekey")==0 && zRight ){
    sqlite3_rekey(db, zRight, sqlite3Strlen30(zRight));
  }else
................................................................................
  }
#endif
pragma_out:
  sqlite3DbFree(db, zLeft);
  sqlite3DbFree(db, zRight);
}

#endif /* SQLITE_OMIT_PRAGMA */

Changes to src/sqliteInt.h.

7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
...
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
....
2886
2887
2888
2889
2890
2891
2892
2893
2894
2895
2896
2897
2898
2899
2900
2901
2902
2903
2904
**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** Internal interface definitions for SQLite.
**
** @(#) $Id: sqliteInt.h,v 1.885 2009/06/18 17:22:39 drh Exp $
*/
#ifndef _SQLITEINT_H_
#define _SQLITEINT_H_

/*
** Include the configuration header output by 'configure' if we're using the
** autoconf-based build
................................................................................
  int nVTrans;                  /* Allocated size of aVTrans */
#endif
  FuncDefHash aFunc;            /* Hash table of connection functions */
  Hash aCollSeq;                /* All collating sequences */
  BusyHandler busyHandler;      /* Busy callback */
  int busyTimeout;              /* Busy handler timeout, in msec */
  Db aDbStatic[2];              /* Static space for the 2 default backends */
#ifdef SQLITE_SSE
  sqlite3_stmt *pFetch;         /* Used by SSE to fetch stored statements */
#endif
  Savepoint *pSavepoint;        /* List of active savepoints */
  int nSavepoint;               /* Number of non-transaction savepoints */
  int nStatement;               /* Number of nested statement-transactions  */
  u8 isTransactionSavepoint;    /* True if the outermost savepoint is a TS */

#ifdef SQLITE_ENABLE_UNLOCK_NOTIFY
  /* The following variables are all protected by the STATIC_MASTER 
................................................................................
  void sqlite3ConnectionClosed(sqlite3 *db);
#else
  #define sqlite3ConnectionBlocked(x,y)
  #define sqlite3ConnectionUnlocked(x)
  #define sqlite3ConnectionClosed(x)
#endif


#ifdef SQLITE_SSE
#include "sseInt.h"
#endif

#ifdef SQLITE_DEBUG
  void sqlite3ParserTrace(FILE*, char *);
#endif

/*
** If the SQLITE_ENABLE IOTRACE exists then the global variable
** sqlite3IoTrace is a pointer to a printf-like routine used to







|







 







<
<
<







 







<
<
<
<
<







7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
...
844
845
846
847
848
849
850



851
852
853
854
855
856
857
....
2883
2884
2885
2886
2887
2888
2889





2890
2891
2892
2893
2894
2895
2896
**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** Internal interface definitions for SQLite.
**
** @(#) $Id: sqliteInt.h,v 1.886 2009/06/19 14:06:03 drh Exp $
*/
#ifndef _SQLITEINT_H_
#define _SQLITEINT_H_

/*
** Include the configuration header output by 'configure' if we're using the
** autoconf-based build
................................................................................
  int nVTrans;                  /* Allocated size of aVTrans */
#endif
  FuncDefHash aFunc;            /* Hash table of connection functions */
  Hash aCollSeq;                /* All collating sequences */
  BusyHandler busyHandler;      /* Busy callback */
  int busyTimeout;              /* Busy handler timeout, in msec */
  Db aDbStatic[2];              /* Static space for the 2 default backends */



  Savepoint *pSavepoint;        /* List of active savepoints */
  int nSavepoint;               /* Number of non-transaction savepoints */
  int nStatement;               /* Number of nested statement-transactions  */
  u8 isTransactionSavepoint;    /* True if the outermost savepoint is a TS */

#ifdef SQLITE_ENABLE_UNLOCK_NOTIFY
  /* The following variables are all protected by the STATIC_MASTER 
................................................................................
  void sqlite3ConnectionClosed(sqlite3 *db);
#else
  #define sqlite3ConnectionBlocked(x,y)
  #define sqlite3ConnectionUnlocked(x)
  #define sqlite3ConnectionClosed(x)
#endif






#ifdef SQLITE_DEBUG
  void sqlite3ParserTrace(FILE*, char *);
#endif

/*
** If the SQLITE_ENABLE IOTRACE exists then the global variable
** sqlite3IoTrace is a pointer to a printf-like routine used to

Changes to src/test_config.c.

12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
...
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
** 
** This file contains code used for testing the SQLite system.
** None of the code in this file goes into a deliverable build.
** 
** The focus of this file is providing the TCL testing layer
** access to compile-time constants.
**
** $Id: test_config.c,v 1.49 2009/06/09 13:42:25 drh Exp $
*/

#include "sqliteLimit.h"

#include "sqliteInt.h"
#include "tcl.h"
#include <stdlib.h>
................................................................................

#ifdef SQLITE_OMIT_PAGER_PRAGMAS
  Tcl_SetVar2(interp, "sqlite_options", "pager_pragmas", "0", TCL_GLOBAL_ONLY);
#else
  Tcl_SetVar2(interp, "sqlite_options", "pager_pragmas", "1", TCL_GLOBAL_ONLY);
#endif

#ifdef SQLITE_OMIT_PARSER
  Tcl_SetVar2(interp, "sqlite_options", "parser", "0", TCL_GLOBAL_ONLY);
#else
  Tcl_SetVar2(interp, "sqlite_options", "parser", "1", TCL_GLOBAL_ONLY);
#endif

#if defined(SQLITE_OMIT_PRAGMA) || defined(SQLITE_OMIT_FLAG_PRAGMAS)
  Tcl_SetVar2(interp, "sqlite_options", "pragma", "0", TCL_GLOBAL_ONLY);
  Tcl_SetVar2(interp, "sqlite_options", "integrityck", "0", TCL_GLOBAL_ONLY);
#else
  Tcl_SetVar2(interp, "sqlite_options", "pragma", "1", TCL_GLOBAL_ONLY);
#endif








|







 







<
<
<
<
<
<







12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
...
355
356
357
358
359
360
361






362
363
364
365
366
367
368
** 
** This file contains code used for testing the SQLite system.
** None of the code in this file goes into a deliverable build.
** 
** The focus of this file is providing the TCL testing layer
** access to compile-time constants.
**
** $Id: test_config.c,v 1.50 2009/06/19 14:06:03 drh Exp $
*/

#include "sqliteLimit.h"

#include "sqliteInt.h"
#include "tcl.h"
#include <stdlib.h>
................................................................................

#ifdef SQLITE_OMIT_PAGER_PRAGMAS
  Tcl_SetVar2(interp, "sqlite_options", "pager_pragmas", "0", TCL_GLOBAL_ONLY);
#else
  Tcl_SetVar2(interp, "sqlite_options", "pager_pragmas", "1", TCL_GLOBAL_ONLY);
#endif







#if defined(SQLITE_OMIT_PRAGMA) || defined(SQLITE_OMIT_FLAG_PRAGMAS)
  Tcl_SetVar2(interp, "sqlite_options", "pragma", "0", TCL_GLOBAL_ONLY);
  Tcl_SetVar2(interp, "sqlite_options", "integrityck", "0", TCL_GLOBAL_ONLY);
#else
  Tcl_SetVar2(interp, "sqlite_options", "pragma", "1", TCL_GLOBAL_ONLY);
#endif

Changes to src/vdbe.c.

39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
....
4556
4557
4558
4559
4560
4561
4562
4563
4564
4565
4566
4567
4568
4569
4570
4571
4572
4573
4574
4575
4576
4577
4578
4579
4580
4581
4582
**
** Various scripts scan this source file in order to generate HTML
** documentation, headers files, or other derived files.  The formatting
** of the code in this file is, therefore, important.  See other comments
** in this file for details.  If in doubt, do not deviate from existing
** commenting and indentation practices when changing or adding code.
**
** $Id: vdbe.c,v 1.855 2009/06/18 00:41:56 drh Exp $
*/
#include "sqliteInt.h"
#include "vdbeInt.h"

/*
** The following global variable is incremented every time a cursor
** moves, either by the OP_SeekXX, OP_Next, or OP_Prev opcodes.  The test
................................................................................
  sqlite3BtreeLeaveAll(db);
  if( rc==SQLITE_NOMEM ){
    goto no_mem;
  }
  break;  
}

#if !defined(SQLITE_OMIT_ANALYZE) && !defined(SQLITE_OMIT_PARSER)
/* Opcode: LoadAnalysis P1 * * * *
**
** Read the sqlite_stat1 table for database P1 and load the content
** of that table into the internal index hash table.  This will cause
** the analysis to be used when preparing all subsequent queries.
*/
case OP_LoadAnalysis: {
  assert( pOp->p1>=0 && pOp->p1<db->nDb );
  rc = sqlite3AnalysisLoad(db, pOp->p1);
  break;  
}
#endif /* !defined(SQLITE_OMIT_ANALYZE) && !defined(SQLITE_OMIT_PARSER)  */

/* Opcode: DropTable P1 * * P4 *
**
** Remove the internal (in-memory) data structures that describe
** the table named P4 in database P1.  This is called after a table
** is dropped in order to keep the internal representation of the
** schema consistent with what is on disk.







|







 







|











|







39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
....
4556
4557
4558
4559
4560
4561
4562
4563
4564
4565
4566
4567
4568
4569
4570
4571
4572
4573
4574
4575
4576
4577
4578
4579
4580
4581
4582
**
** Various scripts scan this source file in order to generate HTML
** documentation, headers files, or other derived files.  The formatting
** of the code in this file is, therefore, important.  See other comments
** in this file for details.  If in doubt, do not deviate from existing
** commenting and indentation practices when changing or adding code.
**
** $Id: vdbe.c,v 1.856 2009/06/19 14:06:03 drh Exp $
*/
#include "sqliteInt.h"
#include "vdbeInt.h"

/*
** The following global variable is incremented every time a cursor
** moves, either by the OP_SeekXX, OP_Next, or OP_Prev opcodes.  The test
................................................................................
  sqlite3BtreeLeaveAll(db);
  if( rc==SQLITE_NOMEM ){
    goto no_mem;
  }
  break;  
}

#if !defined(SQLITE_OMIT_ANALYZE)
/* Opcode: LoadAnalysis P1 * * * *
**
** Read the sqlite_stat1 table for database P1 and load the content
** of that table into the internal index hash table.  This will cause
** the analysis to be used when preparing all subsequent queries.
*/
case OP_LoadAnalysis: {
  assert( pOp->p1>=0 && pOp->p1<db->nDb );
  rc = sqlite3AnalysisLoad(db, pOp->p1);
  break;  
}
#endif /* !defined(SQLITE_OMIT_ANALYZE) */

/* Opcode: DropTable P1 * * P4 *
**
** Remove the internal (in-memory) data structures that describe
** the table named P4 in database P1.  This is called after a table
** is dropped in order to keep the internal representation of the
** schema consistent with what is on disk.

Changes to src/vdbeInt.h.

11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
...
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274


275
276


277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305

306
307
308
309
310
311
312
313
314
315
316
317
318
319
320

321
322
323
324
325
326
327
*************************************************************************
** This is the header file for information that is private to the
** VDBE.  This information used to all be at the top of the single
** source code file "vdbe.c".  When that file became too big (over
** 6000 lines long) it was split up into several smaller files and
** this header information was factored out.
**
** $Id: vdbeInt.h,v 1.171 2009/06/05 14:17:25 drh Exp $
*/
#ifndef _VDBEINT_H_
#define _VDBEINT_H_

/*
** intToKey() and keyToInt() used to transform the rowid.  But with
** the latest versions of the design they are no-ops.
................................................................................
** set to 2 for xDestroy method calls and 1 for all other methods. This
** variable is used for two purposes: to allow xDestroy methods to execute
** "DROP TABLE" statements and to prevent some nasty side effects of
** malloc failure when SQLite is invoked recursively by a virtual table 
** method function.
*/
struct Vdbe {
  sqlite3 *db;        /* The whole database */
  Vdbe *pPrev,*pNext; /* Linked list of VDBEs with the same Vdbe.db */
  int nOp;            /* Number of instructions in the program */
  int nOpAlloc;       /* Number of slots allocated for aOp[] */
  Op *aOp;            /* Space to hold the virtual machine's program */
  int nLabel;         /* Number of labels used */
  int nLabelAlloc;    /* Number of slots allocated in aLabel[] */
  int *aLabel;        /* Space to hold the labels */
  Mem **apArg;        /* Arguments to currently executing user function */
  Mem *aColName;      /* Column names to return */


  int nCursor;        /* Number of slots in apCsr[] */
  VdbeCursor **apCsr; /* One element of this array for each open cursor */


  int nVar;           /* Number of entries in aVar[] */
  Mem *aVar;          /* Values for the OP_Variable opcode. */
  char **azVar;       /* Name of variables */
  int okVar;          /* True if azVar[] has been initialized */
  u32 magic;              /* Magic number for sanity checking */
  int nMem;               /* Number of memory locations currently allocated */
  Mem *aMem;              /* The memory locations */
  int cacheCtr;           /* VdbeCursor row cache generation counter */
  int contextStackTop;    /* Index of top element in the context stack */
  int contextStackDepth;  /* The size of the "context" stack */
  Context *contextStack;  /* Stack used by opcodes ContextPush & ContextPop*/
  int pc;                 /* The program counter */
  int rc;                 /* Value to return */
  int errorAction;        /* Recovery action to do in case of an error */
  int nResColumn;         /* Number of columns in one row of the result set */
  char **azResColumn;     /* Values for one row of result */ 
  char *zErrMsg;          /* Error message written here */
  Mem *pResultSet;        /* Pointer to an array of results */
  u8 explain;             /* True if EXPLAIN present on SQL command */
  u8 changeCntOn;         /* True to update the change-counter */
  u8 expired;             /* True if the VM needs to be recompiled */
  u8 minWriteFileFormat;  /* Minimum file format for writable database files */
  u8 inVtabMethod;        /* See comments above */
  u8 usesStmtJournal;     /* True if uses a statement journal */
  u8 readOnly;            /* True for read-only statements */
  u8 isPrepareV2;         /* True if prepared with prepare_v2() */
  int nChange;            /* Number of db changes made since last reset */
  i64 startTime;          /* Time when query started - used for profiling */
  int btreeMask;          /* Bitmask of db->aDb[] entries referenced */

  BtreeMutexArray aMutex; /* An array of Btree used here and needing locks */
  int aCounter[2];        /* Counters used by sqlite3_stmt_status() */
  char *zSql;           /* Text of the SQL statement that generated this */
  void *pFree;            /* Free this when deleting the vdbe */
#ifdef SQLITE_DEBUG
  FILE *trace;          /* Write an execution trace here, if not NULL */
#endif
  int iStatement;         /* Statement number (or 0 if has not opened stmt) */
#ifdef SQLITE_SSE
  int fetchId;          /* Statement number used by sqlite3_fetch_statement */
  int lru;              /* Counter used for LRU cache replacement */
#endif
#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
  Vdbe *pLruPrev;
  Vdbe *pLruNext;

#endif
};

/*
** The following are allowed values for Vdbe.magic
*/
#define VDBE_MAGIC_INIT     0x26bceaa5    /* Building a VDBE program */







|







 







|
|
|
|
|
|
|
|
|
|
>
>
|
|
>
>
|
|
|
<









<
<
<

<









<

>


|

<
<
<

|
<
<
<
<
<
<
>







11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
...
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283

284
285
286
287
288
289
290
291
292



293

294
295
296
297
298
299
300
301
302

303
304
305
306
307
308



309
310






311
312
313
314
315
316
317
318
*************************************************************************
** This is the header file for information that is private to the
** VDBE.  This information used to all be at the top of the single
** source code file "vdbe.c".  When that file became too big (over
** 6000 lines long) it was split up into several smaller files and
** this header information was factored out.
**
** $Id: vdbeInt.h,v 1.172 2009/06/19 14:06:03 drh Exp $
*/
#ifndef _VDBEINT_H_
#define _VDBEINT_H_

/*
** intToKey() and keyToInt() used to transform the rowid.  But with
** the latest versions of the design they are no-ops.
................................................................................
** set to 2 for xDestroy method calls and 1 for all other methods. This
** variable is used for two purposes: to allow xDestroy methods to execute
** "DROP TABLE" statements and to prevent some nasty side effects of
** malloc failure when SQLite is invoked recursively by a virtual table 
** method function.
*/
struct Vdbe {
  sqlite3 *db;            /* The database connection that owns this statement */
  Vdbe *pPrev,*pNext;     /* Linked list of VDBEs with the same Vdbe.db */
  int nOp;                /* Number of instructions in the program */
  int nOpAlloc;           /* Number of slots allocated for aOp[] */
  Op *aOp;                /* Space to hold the virtual machine's program */
  int nLabel;             /* Number of labels used */
  int nLabelAlloc;        /* Number of slots allocated in aLabel[] */
  int *aLabel;            /* Space to hold the labels */
  Mem **apArg;            /* Arguments to currently executing user function */
  Mem *aColName;          /* Column names to return */
  Mem *pResultSet;        /* Pointer to an array of results */
  u16 nResColumn;         /* Number of columns in one row of the result set */
  u16 nCursor;            /* Number of slots in apCsr[] */
  VdbeCursor **apCsr;     /* One element of this array for each open cursor */
  u8 errorAction;         /* Recovery action to do in case of an error */
  u8 okVar;               /* True if azVar[] has been initialized */
  u16 nVar;               /* Number of entries in aVar[] */
  Mem *aVar;              /* Values for the OP_Variable opcode. */
  char **azVar;           /* Name of variables */

  u32 magic;              /* Magic number for sanity checking */
  int nMem;               /* Number of memory locations currently allocated */
  Mem *aMem;              /* The memory locations */
  int cacheCtr;           /* VdbeCursor row cache generation counter */
  int contextStackTop;    /* Index of top element in the context stack */
  int contextStackDepth;  /* The size of the "context" stack */
  Context *contextStack;  /* Stack used by opcodes ContextPush & ContextPop*/
  int pc;                 /* The program counter */
  int rc;                 /* Value to return */



  char *zErrMsg;          /* Error message written here */

  u8 explain;             /* True if EXPLAIN present on SQL command */
  u8 changeCntOn;         /* True to update the change-counter */
  u8 expired;             /* True if the VM needs to be recompiled */
  u8 minWriteFileFormat;  /* Minimum file format for writable database files */
  u8 inVtabMethod;        /* See comments above */
  u8 usesStmtJournal;     /* True if uses a statement journal */
  u8 readOnly;            /* True for read-only statements */
  u8 isPrepareV2;         /* True if prepared with prepare_v2() */
  int nChange;            /* Number of db changes made since last reset */

  int btreeMask;          /* Bitmask of db->aDb[] entries referenced */
  i64 startTime;          /* Time when query started - used for profiling */
  BtreeMutexArray aMutex; /* An array of Btree used here and needing locks */
  int aCounter[2];        /* Counters used by sqlite3_stmt_status() */
  char *zSql;             /* Text of the SQL statement that generated this */
  void *pFree;            /* Free this when deleting the vdbe */



  int iStatement;         /* Statement number (or 0 if has not opened stmt) */
#ifdef SQLITE_DEBUG






  FILE *trace;            /* Write an execution trace here, if not NULL */
#endif
};

/*
** The following are allowed values for Vdbe.magic
*/
#define VDBE_MAGIC_INIT     0x26bceaa5    /* Building a VDBE program */

Changes to src/vdbeapi.c.

9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
...
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
...
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
...
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
...
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
...
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
**    May you share freely, never taking more than you give.
**
*************************************************************************
**
** This file contains code use to implement APIs that are part of the
** VDBE.
**
** $Id: vdbeapi.c,v 1.165 2009/06/06 14:13:27 danielk1977 Exp $
*/
#include "sqliteInt.h"
#include "vdbeInt.h"

#if 0 && defined(SQLITE_ENABLE_MEMORY_MANAGEMENT)
/*
** The following structure contains pointers to the end points of a
** doubly-linked list of all compiled SQL statements that may be holding
** buffers eligible for release when the sqlite3_release_memory() interface is
** invoked. Access to this list is protected by the SQLITE_MUTEX_STATIC_LRU2
** mutex.
**
** Statements are added to the end of this list when sqlite3_reset() is
** called. They are removed either when sqlite3_step() or sqlite3_finalize()
** is called. When statements are added to this list, the associated 
** register array (p->aMem[1..p->nMem]) may contain dynamic buffers that
** can be freed using sqlite3VdbeReleaseMemory().
**
** When statements are added or removed from this list, the mutex
** associated with the Vdbe being added or removed (Vdbe.db->mutex) is
** already held. The LRU2 mutex is then obtained, blocking if necessary,
** the linked-list pointers manipulated and the LRU2 mutex relinquished.
*/
struct StatementLruList {
  Vdbe *pFirst;
  Vdbe *pLast;
};
static struct StatementLruList sqlite3LruStatements;

/*
** Check that the list looks to be internally consistent. This is used
** as part of an assert() statement as follows:
**
**   assert( stmtLruCheck() );
*/
#ifndef NDEBUG
static int stmtLruCheck(){
  Vdbe *p;
  for(p=sqlite3LruStatements.pFirst; p; p=p->pLruNext){
    assert(p->pLruNext || p==sqlite3LruStatements.pLast);
    assert(!p->pLruNext || p->pLruNext->pLruPrev==p);
    assert(p->pLruPrev || p==sqlite3LruStatements.pFirst);
    assert(!p->pLruPrev || p->pLruPrev->pLruNext==p);
  }
  return 1;
}
#endif

/*
** Add vdbe p to the end of the statement lru list. It is assumed that
** p is not already part of the list when this is called. The lru list
** is protected by the SQLITE_MUTEX_STATIC_LRU mutex.
*/
static void stmtLruAdd(Vdbe *p){
  sqlite3_mutex_enter(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_LRU2));

  if( p->pLruPrev || p->pLruNext || sqlite3LruStatements.pFirst==p ){
    sqlite3_mutex_leave(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_LRU2));
    return;
  }

  assert( stmtLruCheck() );

  if( !sqlite3LruStatements.pFirst ){
    assert( !sqlite3LruStatements.pLast );
    sqlite3LruStatements.pFirst = p;
    sqlite3LruStatements.pLast = p;
  }else{
    assert( !sqlite3LruStatements.pLast->pLruNext );
    p->pLruPrev = sqlite3LruStatements.pLast;
    sqlite3LruStatements.pLast->pLruNext = p;
    sqlite3LruStatements.pLast = p;
  }

  assert( stmtLruCheck() );

  sqlite3_mutex_leave(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_LRU2));
}

/*
** Assuming the SQLITE_MUTEX_STATIC_LRU2 mutext is already held, remove
** statement p from the least-recently-used statement list. If the 
** statement is not currently part of the list, this call is a no-op.
*/
static void stmtLruRemoveNomutex(Vdbe *p){
  if( p->pLruPrev || p->pLruNext || p==sqlite3LruStatements.pFirst ){
    assert( stmtLruCheck() );
    if( p->pLruNext ){
      p->pLruNext->pLruPrev = p->pLruPrev;
    }else{
      sqlite3LruStatements.pLast = p->pLruPrev;
    }
    if( p->pLruPrev ){
      p->pLruPrev->pLruNext = p->pLruNext;
    }else{
      sqlite3LruStatements.pFirst = p->pLruNext;
    }
    p->pLruNext = 0;
    p->pLruPrev = 0;
    assert( stmtLruCheck() );
  }
}

/*
** Assuming the SQLITE_MUTEX_STATIC_LRU2 mutext is not held, remove
** statement p from the least-recently-used statement list. If the 
** statement is not currently part of the list, this call is a no-op.
*/
static void stmtLruRemove(Vdbe *p){
  sqlite3_mutex_enter(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_LRU2));
  stmtLruRemoveNomutex(p);
  sqlite3_mutex_leave(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_LRU2));
}

/*
** Try to release n bytes of memory by freeing buffers associated 
** with the memory registers of currently unused vdbes.
*/
int sqlite3VdbeReleaseMemory(int n){
  Vdbe *p;
  Vdbe *pNext;
  int nFree = 0;

  sqlite3_mutex_enter(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_LRU2));
  for(p=sqlite3LruStatements.pFirst; p && nFree<n; p=pNext){
    pNext = p->pLruNext;

    /* For each statement handle in the lru list, attempt to obtain the
    ** associated database mutex. If it cannot be obtained, continue
    ** to the next statement handle. It is not possible to block on
    ** the database mutex - that could cause deadlock.
    */
    if( SQLITE_OK==sqlite3_mutex_try(p->db->mutex) ){
      nFree += sqlite3VdbeReleaseBuffers(p);
      stmtLruRemoveNomutex(p);
      sqlite3_mutex_leave(p->db->mutex);
    }
  }
  sqlite3_mutex_leave(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_LRU2));

  return nFree;
}

/*
** Call sqlite3Reprepare() on the statement. Remove it from the
** lru list before doing so, as Reprepare() will free all the
** memory register buffers anyway.
*/
int vdbeReprepare(Vdbe *p){
  stmtLruRemove(p);
  return sqlite3Reprepare(p);
}

#else       /* !SQLITE_ENABLE_MEMORY_MANAGEMENT */
  #define stmtLruRemove(x)
  #define stmtLruAdd(x)
  #define vdbeReprepare(x) sqlite3Reprepare(x)
#endif


#ifndef SQLITE_OMIT_DEPRECATED
/*
** Return TRUE (non-zero) of the statement supplied as an argument needs
** to be recompiled.  A statement needs to be recompiled whenever the
** execution environment changes in a way that would alter the program
** that sqlite3_prepare() generates.  For example, if new functions or
................................................................................
  }else{
    Vdbe *v = (Vdbe*)pStmt;
    sqlite3 *db = v->db;
#if SQLITE_THREADSAFE
    sqlite3_mutex *mutex = v->db->mutex;
#endif
    sqlite3_mutex_enter(mutex);
    stmtLruRemove(v);
    rc = sqlite3VdbeFinalize(v);
    rc = sqlite3ApiExit(db, rc);
    sqlite3_mutex_leave(mutex);
  }
  return rc;
}

................................................................................
  int rc;
  if( pStmt==0 ){
    rc = SQLITE_OK;
  }else{
    Vdbe *v = (Vdbe*)pStmt;
    sqlite3_mutex_enter(v->db->mutex);
    rc = sqlite3VdbeReset(v);
    stmtLruAdd(v);
    sqlite3VdbeMakeReady(v, -1, 0, 0, 0);
    assert( (rc & (v->db->errMask))==rc );
    rc = sqlite3ApiExit(v->db, rc);
    sqlite3_mutex_leave(v->db->mutex);
  }
  return rc;
}
................................................................................
      p->startTime = (u64)((rNow - (int)rNow)*3600.0*24.0*1000000000.0);
    }
#endif

    db->activeVdbeCnt++;
    if( p->readOnly==0 ) db->writeVdbeCnt++;
    p->pc = 0;
    stmtLruRemove(p);
  }
#ifndef SQLITE_OMIT_EXPLAIN
  if( p->explain ){
    rc = sqlite3VdbeList(p);
  }else
#endif /* SQLITE_OMIT_EXPLAIN */
  {
................................................................................
}

/*
** This is the top-level implementation of sqlite3_step().  Call
** sqlite3Step() to do most of the work.  If a schema error occurs,
** call sqlite3Reprepare() and try again.
*/
#ifdef SQLITE_OMIT_PARSER
int sqlite3_step(sqlite3_stmt *pStmt){
  int rc = SQLITE_MISUSE;
  if( pStmt ){
    Vdbe *v;
    v = (Vdbe*)pStmt;
    sqlite3_mutex_enter(v->db->mutex);
    rc = sqlite3Step(v);
    sqlite3_mutex_leave(v->db->mutex);
  }
  return rc;
}
#else
int sqlite3_step(sqlite3_stmt *pStmt){
  int rc = SQLITE_MISUSE;
  if( pStmt ){
    int cnt = 0;
    Vdbe *v = (Vdbe*)pStmt;
    sqlite3 *db = v->db;
    sqlite3_mutex_enter(db->mutex);
    while( (rc = sqlite3Step(v))==SQLITE_SCHEMA
           && cnt++ < 5
           && (rc = vdbeReprepare(v))==SQLITE_OK ){
      sqlite3_reset(pStmt);
      v->expired = 0;
    }
    if( rc==SQLITE_SCHEMA && ALWAYS(v->isPrepareV2) && ALWAYS(db->pErr) ){
      /* This case occurs after failing to recompile an sql statement. 
      ** The error message from the SQL compiler has already been loaded 
      ** into the database handle. This block copies the error message 
................................................................................
      }
    }
    rc = sqlite3ApiExit(db, rc);
    sqlite3_mutex_leave(db->mutex);
  }
  return rc;
}
#endif

/*
** Extract the user data from a sqlite3_context structure and return a
** pointer to it.
*/
void *sqlite3_user_data(sqlite3_context *p){
  assert( p && p->pFunc );







|



<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<







 







<







 







<







 







<







 







<
<
<
<
<
<
<
<
<
<
<
<
<









|







 







<







9
10
11
12
13
14
15
16
17
18
19




























































































































































20
21
22
23
24
25
26
..
49
50
51
52
53
54
55

56
57
58
59
60
61
62
..
72
73
74
75
76
77
78

79
80
81
82
83
84
85
...
315
316
317
318
319
320
321

322
323
324
325
326
327
328
...
374
375
376
377
378
379
380













381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
...
410
411
412
413
414
415
416

417
418
419
420
421
422
423
**    May you share freely, never taking more than you give.
**
*************************************************************************
**
** This file contains code use to implement APIs that are part of the
** VDBE.
**
** $Id: vdbeapi.c,v 1.166 2009/06/19 14:06:03 drh Exp $
*/
#include "sqliteInt.h"
#include "vdbeInt.h"





























































































































































#ifndef SQLITE_OMIT_DEPRECATED
/*
** Return TRUE (non-zero) of the statement supplied as an argument needs
** to be recompiled.  A statement needs to be recompiled whenever the
** execution environment changes in a way that would alter the program
** that sqlite3_prepare() generates.  For example, if new functions or
................................................................................
  }else{
    Vdbe *v = (Vdbe*)pStmt;
    sqlite3 *db = v->db;
#if SQLITE_THREADSAFE
    sqlite3_mutex *mutex = v->db->mutex;
#endif
    sqlite3_mutex_enter(mutex);

    rc = sqlite3VdbeFinalize(v);
    rc = sqlite3ApiExit(db, rc);
    sqlite3_mutex_leave(mutex);
  }
  return rc;
}

................................................................................
  int rc;
  if( pStmt==0 ){
    rc = SQLITE_OK;
  }else{
    Vdbe *v = (Vdbe*)pStmt;
    sqlite3_mutex_enter(v->db->mutex);
    rc = sqlite3VdbeReset(v);

    sqlite3VdbeMakeReady(v, -1, 0, 0, 0);
    assert( (rc & (v->db->errMask))==rc );
    rc = sqlite3ApiExit(v->db, rc);
    sqlite3_mutex_leave(v->db->mutex);
  }
  return rc;
}
................................................................................
      p->startTime = (u64)((rNow - (int)rNow)*3600.0*24.0*1000000000.0);
    }
#endif

    db->activeVdbeCnt++;
    if( p->readOnly==0 ) db->writeVdbeCnt++;
    p->pc = 0;

  }
#ifndef SQLITE_OMIT_EXPLAIN
  if( p->explain ){
    rc = sqlite3VdbeList(p);
  }else
#endif /* SQLITE_OMIT_EXPLAIN */
  {
................................................................................
}

/*
** This is the top-level implementation of sqlite3_step().  Call
** sqlite3Step() to do most of the work.  If a schema error occurs,
** call sqlite3Reprepare() and try again.
*/













int sqlite3_step(sqlite3_stmt *pStmt){
  int rc = SQLITE_MISUSE;
  if( pStmt ){
    int cnt = 0;
    Vdbe *v = (Vdbe*)pStmt;
    sqlite3 *db = v->db;
    sqlite3_mutex_enter(db->mutex);
    while( (rc = sqlite3Step(v))==SQLITE_SCHEMA
           && cnt++ < 5
           && (rc = sqlite3Reprepare(v))==SQLITE_OK ){
      sqlite3_reset(pStmt);
      v->expired = 0;
    }
    if( rc==SQLITE_SCHEMA && ALWAYS(v->isPrepareV2) && ALWAYS(db->pErr) ){
      /* This case occurs after failing to recompile an sql statement. 
      ** The error message from the SQL compiler has already been loaded 
      ** into the database handle. This block copies the error message 
................................................................................
      }
    }
    rc = sqlite3ApiExit(db, rc);
    sqlite3_mutex_leave(db->mutex);
  }
  return rc;
}


/*
** Extract the user data from a sqlite3_context structure and return a
** pointer to it.
*/
void *sqlite3_user_data(sqlite3_context *p){
  assert( p && p->pFunc );