SQLite Android Bindings

/******************************************************************************
** This file is an amalgamation of many separate C source files from SQLite
** version 3.16.0.  By combining all the individual C code files into this
** single large file, the entire code can be compiled as a single translation
** unit.  This allows many compilers to do optimizations that would not be
** possible if the files were compiled separately.  Performance improvements
** of 5% or more are commonly seen when SQLite is compiled as a single
** translation unit.
**
** This file is all you need to compile SQLite.  To use SQLite in other

** string contains the date and time of the check-in (UTC) and an SHA1
** hash of the entire source tree.
**
** See also: [sqlite3_libversion()],
** [sqlite3_libversion_number()], [sqlite3_sourceid()],
** [sqlite_version()] and [sqlite_source_id()].
*/
#define SQLITE_VERSION        "3.16.0"
#define SQLITE_VERSION_NUMBER 3016000
#define SQLITE_SOURCE_ID      "2017-01-02 11:57:58 04ac0b75b1716541b2b97704f4809cb7ef19cccf"

/*
** CAPI3REF: Run-Time Library Version Numbers
** KEYWORDS: sqlite3_version sqlite3_sourceid
**
** These interfaces provide the same information as the [SQLITE_VERSION],
** [SQLITE_VERSION_NUMBER], and [SQLITE_SOURCE_ID] C preprocessor macros
** but are associated with the library instead of the header file.  ^(Cautious
** programmers might include assert() statements in their application to
** verify that values returned by these interfaces match the macros in
** the header, and thus ensure that the application is

#define SQLITE_FCNTL_WIN32_SET_HANDLE       23
#define SQLITE_FCNTL_WAL_BLOCK              24
#define SQLITE_FCNTL_ZIPVFS                 25
#define SQLITE_FCNTL_RBU                    26
#define SQLITE_FCNTL_VFS_POINTER            27
#define SQLITE_FCNTL_JOURNAL_POINTER        28
#define SQLITE_FCNTL_WIN32_GET_HANDLE       29
#define SQLITE_FCNTL_PDB                    30

/* deprecated names */
#define SQLITE_GET_LOCKPROXYFILE      SQLITE_FCNTL_GET_LOCKPROXYFILE
#define SQLITE_SET_LOCKPROXYFILE      SQLITE_FCNTL_SET_LOCKPROXYFILE
#define SQLITE_LAST_ERRNO             SQLITE_FCNTL_LAST_ERRNO

** schema.  ^The sole argument is a pointer to a constant UTF8 string
** which will become the new schema name in place of "main".  ^SQLite
** does not make a copy of the new main schema name string, so the application
** must ensure that the argument passed into this DBCONFIG option is unchanged
** until after the database connection closes.
** </dd>
**
** <dt>SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE</dt>
** <dd> Usually, when a database in wal mode is closed or detached from a 
** database handle, SQLite checks if this will mean that there are now no 
** connections at all to the database. If so, it performs a checkpoint 
** operation before closing the connection. This option may be used to
** override this behaviour. The first parameter passed to this operation
** is an integer - non-zero to disable checkpoints-on-close, or zero (the
** default) to enable them. The second parameter is a pointer to an integer
** into which is written 0 or 1 to indicate whether checkpoints-on-close
** have been disabled - 0 if they are not disabled, 1 if they are.
** </dd>
**
** </dl>
*/
#define SQLITE_DBCONFIG_MAINDBNAME            1000 /* const char* */
#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_ENABLE_FTS3_TOKENIZER 1004 /* int int* */
#define SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION 1005 /* int int* */
#define SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE      1006 /* int int* */


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

** [SAVEPOINT], and [RELEASE] cause sqlite3_stmt_readonly() to return true,
** since the statements themselves do not actually modify the database but
** rather they control the timing of when other statements modify the 
** database.  ^The [ATTACH] and [DETACH] statements also cause
** sqlite3_stmt_readonly() to return true since, while those statements
** change the configuration of a database connection, they do not make 
** changes to the content of the database files on disk.
** ^The sqlite3_stmt_readonly() interface returns true for [BEGIN] since
** [BEGIN] merely sets internal flags, but the [BEGIN|BEGIN IMMEDIATE] and
** [BEGIN|BEGIN EXCLUSIVE] commands do touch the database and so
** sqlite3_stmt_readonly() returns false for those commands.
*/
SQLITE_API int sqlite3_stmt_readonly(sqlite3_stmt *pStmt);

/*
** CAPI3REF: Determine If A Prepared Statement Has Been Reset
** METHOD: sqlite3_stmt
**

** callback was invoked as a result of a direct insert, update, or delete
** operation; or 1 for inserts, updates, or deletes invoked by top-level 
** triggers; or 2 for changes resulting from triggers called by top-level
** triggers; and so forth.
**
** See also:  [sqlite3_update_hook()]
*/
#if defined(SQLITE_ENABLE_PREUPDATE_HOOK)
SQLITE_API void *sqlite3_preupdate_hook(
  sqlite3 *db,
  void(*xPreUpdate)(
    void *pCtx,                   /* Copy of third arg to preupdate_hook() */
    sqlite3 *db,                  /* Database handle */
    int op,                       /* SQLITE_UPDATE, DELETE or INSERT */
    char const *zDb,              /* Database name */
    char const *zName,            /* Table name */
    sqlite3_int64 iKey1,          /* Rowid of row about to be deleted/updated */
    sqlite3_int64 iKey2           /* New rowid value (for a rowid UPDATE) */
  ),
  void*
);
SQLITE_API int sqlite3_preupdate_old(sqlite3 *, int, sqlite3_value **);
SQLITE_API int sqlite3_preupdate_count(sqlite3 *);
SQLITE_API int sqlite3_preupdate_depth(sqlite3 *);
SQLITE_API int sqlite3_preupdate_new(sqlite3 *, int, sqlite3_value **);
#endif

/*
** CAPI3REF: Low-level system error code
**
** ^Attempt to return the underlying operating system error code or error
** number that caused the most recent I/O error or failure to open a file.
** The return value is OS-dependent.  For example, on unix systems, after
** [sqlite3_open_v2()] returns [SQLITE_CANTOPEN], this interface could be
** called to get back the underlying "errno" that caused the problem, such
** as ENOSPC, EAUTH, EISDIR, and so forth.  
*/
SQLITE_API int sqlite3_system_errno(sqlite3*);

/*
** CAPI3REF: Database Snapshot
** KEYWORDS: {snapshot} {sqlite3_snapshot}
** EXPERIMENTAL
**
** An instance of the snapshot object records the state of a [WAL mode]
** database for some specific point in history.
**
** In [WAL mode], multiple [database connections] that are open on the
** same database file can each be reading a different historical version

** the most recent version.
**
** The constructor for this object is [sqlite3_snapshot_get()].  The
** [sqlite3_snapshot_open()] method causes a fresh read transaction to refer
** to an historical snapshot (if possible).  The destructor for 
** sqlite3_snapshot objects is [sqlite3_snapshot_free()].
*/
typedef struct sqlite3_snapshot {
  unsigned char hidden[48];
} sqlite3_snapshot;

/*
** CAPI3REF: Record A Database Snapshot
** EXPERIMENTAL
**
** ^The [sqlite3_snapshot_get(D,S,P)] interface attempts to make a
** new [sqlite3_snapshot] object that records the current state of
** schema S in database connection D.  ^On success, the
** [sqlite3_snapshot_get(D,S,P)] interface writes a pointer to the newly
** created [sqlite3_snapshot] object into *P and returns SQLITE_OK.
** If there is not already a read-transaction open on schema S when
** this function is called, one is opened automatically. 
**
** The following must be true for this function to succeed. If any of
** the following statements are false when sqlite3_snapshot_get() is
** called, SQLITE_ERROR is returned. The final value of *P is undefined
** in this case. 
**
** <ul>
**   <li> The database handle must be in [autocommit mode].
**
**   <li> Schema S of [database connection] D must be a [WAL mode] database.
**
**   <li> There must not be a write transaction open on schema S of database
**        connection D.
**
**   <li> One or more transactions must have been written to the current wal
**        file since it was created on disk (by any connection). This means
**        that a snapshot cannot be taken on a wal mode database with no wal 
**        file immediately after it is first opened. At least one transaction
**        must be written to it first.
** </ul>
**
** This function may also return SQLITE_NOMEM.  If it is called with the
** database handle in autocommit mode but fails for some other reason, 
** whether or not a read transaction is opened on schema S is undefined.

**
** The [sqlite3_snapshot] object returned from a successful call to
** [sqlite3_snapshot_get()] must be freed using [sqlite3_snapshot_free()]
** to avoid a memory leak.
**
** The [sqlite3_snapshot_get()] interface is only available when the
** SQLITE_ENABLE_SNAPSHOT compile-time option is used.

** snapshot, and a positive value if P1 is a newer snapshot than P2.
*/
SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_snapshot_cmp(
  sqlite3_snapshot *p1,
  sqlite3_snapshot *p2
);

/*
** CAPI3REF: Recover snapshots from a wal file
** EXPERIMENTAL
**
** If all connections disconnect from a database file but do not perform
** a checkpoint, the existing wal file is opened along with the database
** file the next time the database is opened. At this point it is only
** possible to successfully call sqlite3_snapshot_open() to open the most
** recent snapshot of the database (the one at the head of the wal file),
** even though the wal file may contain other valid snapshots for which
** clients have sqlite3_snapshot handles.
**
** This function attempts to scan the wal file associated with database zDb
** of database handle db and make all valid snapshots available to
** sqlite3_snapshot_open(). It is an error if there is already a read
** transaction open on the database, or if the database is not a wal mode
** database.
**
** SQLITE_OK is returned if successful, or an SQLite error code otherwise.
*/
SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_snapshot_recover(sqlite3 *db, const char *zDb);

/*
** Undo the hack that converts floating point types to integer for
** builds on processors without floating point support.
*/
#ifdef SQLITE_OMIT_FLOATING_POINT
# undef double
#endif

typedef struct UnpackedRecord UnpackedRecord;
typedef struct VTable VTable;
typedef struct VtabCtx VtabCtx;
typedef struct Walker Walker;
typedef struct WhereInfo WhereInfo;
typedef struct With With;

/* A VList object records a mapping between parameters/variables/wildcards
** in the SQL statement (such as $abc, @pqr, or :xyz) and the integer
** variable number associated with that parameter.  See the format description
** on the sqlite3VListAdd() routine for more information.  A VList is really
** just an array of integers.
*/
typedef int VList;

/*
** Defer sourcing vdbe.h and btree.h until after the "u8" and
** "BusyHandler" typedefs. vdbe.h also requires a few of the opaque
** pointer types (i.e. FuncDef) defined above.
*/
/************** Include btree.h in the middle of sqliteInt.h *****************/
/************** Begin file btree.h *******************************************/

** organized and understandable, and it also helps the resulting code to
** run a little faster by using fewer registers for parameter passing.
*/
struct BtreePayload {
  const void *pKey;       /* Key content for indexes.  NULL for tables */
  sqlite3_int64 nKey;     /* Size of pKey for indexes.  PRIMARY KEY for tabs */
  const void *pData;      /* Data for tables.  NULL for indexes */
  struct Mem *aMem;       /* First of nMem value in the unpacked pKey */
  u16 nMem;               /* Number of aMem[] value.  Might be zero */
  int nData;              /* Size of pData.  0 if none. */
  int nZero;              /* Extra zero data appended after pData,nData */
};

SQLITE_PRIVATE int sqlite3BtreeInsert(BtCursor*, const BtreePayload *pPayload,
                       int bias, int seekResult);
SQLITE_PRIVATE int sqlite3BtreeFirst(BtCursor*, int *pRes);
SQLITE_PRIVATE int sqlite3BtreeLast(BtCursor*, int *pRes);
SQLITE_PRIVATE int sqlite3BtreeNext(BtCursor*, int *pRes);
SQLITE_PRIVATE int sqlite3BtreeEof(BtCursor*);
SQLITE_PRIVATE int sqlite3BtreePrevious(BtCursor*, int *pRes);
SQLITE_PRIVATE i64 sqlite3BtreeIntegerKey(BtCursor*);
SQLITE_PRIVATE int sqlite3BtreePayload(BtCursor*, u32 offset, u32 amt, void*);
SQLITE_PRIVATE const void *sqlite3BtreePayloadFetch(BtCursor*, u32 *pAmt);
SQLITE_PRIVATE u32 sqlite3BtreePayloadSize(BtCursor*);


SQLITE_PRIVATE char *sqlite3BtreeIntegrityCheck(Btree*, int *aRoot, int nRoot, int, int*);
SQLITE_PRIVATE struct Pager *sqlite3BtreePager(Btree*);

#ifndef SQLITE_OMIT_INCRBLOB
SQLITE_PRIVATE int sqlite3BtreePayloadChecked(BtCursor*, u32 offset, u32 amt, void*);
SQLITE_PRIVATE int sqlite3BtreePutData(BtCursor*, u32 offset, u32 amt, void*);
SQLITE_PRIVATE void sqlite3BtreeIncrblobCursor(BtCursor *);
#endif
SQLITE_PRIVATE void sqlite3BtreeClearCursor(BtCursor *);
SQLITE_PRIVATE int sqlite3BtreeSetVersion(Btree *pBt, int iVersion);
SQLITE_PRIVATE int sqlite3BtreeCursorHasHint(BtCursor*, unsigned int mask);
SQLITE_PRIVATE int sqlite3BtreeIsReadonly(Btree *pBt);
SQLITE_PRIVATE int sqlite3HeaderSizeBtree(void);

#ifndef NDEBUG
SQLITE_PRIVATE int sqlite3BtreeCursorIsValid(BtCursor*);
#endif
SQLITE_PRIVATE int sqlite3BtreeCursorIsValidNN(BtCursor*);

#ifndef SQLITE_OMIT_BTREECOUNT
SQLITE_PRIVATE int sqlite3BtreeCount(BtCursor *, i64 *);
#endif

#ifdef SQLITE_TEST
SQLITE_PRIVATE int sqlite3BtreeCursorInfo(BtCursor*, int*, int);

/*
** Allowed values of VdbeOp.p4type
*/
#define P4_NOTUSED    0   /* The P4 parameter is not used */
#define P4_DYNAMIC  (-1)  /* Pointer to a string obtained from sqliteMalloc() */
#define P4_STATIC   (-2)  /* Pointer to a static string */
#define P4_COLLSEQ  (-3)  /* P4 is a pointer to a CollSeq structure */
#define P4_FUNCDEF  (-4)  /* P4 is a pointer to a FuncDef structure */
#define P4_KEYINFO  (-5)  /* P4 is a pointer to a KeyInfo structure */
#define P4_EXPR     (-6)  /* P4 is a pointer to an Expr tree */
#define P4_MEM      (-7)  /* P4 is a pointer to a Mem*    structure */
#define P4_TRANSIENT  0   /* P4 is a pointer to a transient string */
#define P4_VTAB     (-8) /* P4 is a pointer to an sqlite3_vtab structure */

#define P4_REAL     (-9) /* P4 is a 64-bit floating point value */
#define P4_INT64    (-10) /* P4 is a 64-bit signed integer */
#define P4_INT32    (-11) /* P4 is a 32-bit signed integer */
#define P4_INTARRAY (-12) /* P4 is a vector of 32-bit integers */
#define P4_SUBPROGRAM  (-13) /* P4 is a pointer to a SubProgram structure */
#define P4_ADVANCE  (-14) /* P4 is a pointer to BtreeNext() or BtreePrev() */
#define P4_TABLE    (-15) /* P4 is a pointer to a Table structure */
#define P4_FUNCCTX  (-16) /* P4 is a pointer to an sqlite3_context object */

/* Error message codes for OP_Halt */
#define P5_ConstraintNotNull 1
#define P5_ConstraintUnique  2
#define P5_ConstraintCheck   3
#define P5_ConstraintFK      4

#define OP_IdxLT          60 /* synopsis: key=r[P3@P4]                     */
#define OP_IdxGE          61 /* synopsis: key=r[P3@P4]                     */
#define OP_RowSetRead     62 /* synopsis: r[P3]=rowset(P1)                 */
#define OP_RowSetTest     63 /* synopsis: if r[P3] in rowset(P1) goto P2   */
#define OP_Program        64
#define OP_FkIfZero       65 /* synopsis: if fkctr[P1]==0 goto P2          */
#define OP_IfPos          66 /* synopsis: if r[P1]>0 then r[P1]-=P3, goto P2 */
#define OP_IfNotZero      67 /* synopsis: if r[P1]!=0 then r[P1]--, goto P2 */
#define OP_DecrJumpZero   68 /* synopsis: if (--r[P1])==0 goto P2          */
#define OP_IncrVacuum     69
#define OP_VNext          70
#define OP_Init           71 /* synopsis: Start at P2                      */
#define OP_Return         72
#define OP_EndCoroutine   73
#define OP_HaltIfNull     74 /* synopsis: if r[P3]=null halt               */

#define OP_NewRowid      114 /* synopsis: r[P2]=rowid                      */
#define OP_Insert        115 /* synopsis: intkey=r[P3] data=r[P2]          */
#define OP_InsertInt     116 /* synopsis: intkey=P3 data=r[P2]             */
#define OP_Delete        117
#define OP_ResetCount    118
#define OP_SorterCompare 119 /* synopsis: if key(P1)!=trim(r[P3],P4) goto P2 */
#define OP_SorterData    120 /* synopsis: r[P2]=data                       */

#define OP_RowData       121 /* synopsis: r[P2]=data                       */
#define OP_Rowid         122 /* synopsis: r[P2]=rowid                      */
#define OP_NullRow       123
#define OP_SorterInsert  124 /* synopsis: key=r[P2]                        */
#define OP_IdxInsert     125 /* synopsis: key=r[P2]                        */
#define OP_IdxDelete     126 /* synopsis: key=r[P2@P3]                     */
#define OP_Seek          127 /* synopsis: Move P3 to P1.rowid              */
#define OP_IdxRowid      128 /* synopsis: r[P2]=rowid                      */
#define OP_Destroy       129
#define OP_Clear         130
#define OP_ResetSorter   131
#define OP_Real          132 /* same as TK_FLOAT, synopsis: r[P2]=P4       */

#define OP_CreateIndex   133 /* synopsis: r[P2]=root iDb=P1                */
#define OP_CreateTable   134 /* synopsis: r[P2]=root iDb=P1                */
#define OP_ParseSchema   135
#define OP_LoadAnalysis  136
#define OP_DropTable     137
#define OP_DropIndex     138
#define OP_DropTrigger   139
#define OP_IntegrityCk   140
#define OP_RowSetAdd     141 /* synopsis: rowset(P1)=r[P2]                 */
#define OP_Param         142
#define OP_FkCounter     143 /* synopsis: fkctr[P1]+=P2                    */
#define OP_MemMax        144 /* synopsis: r[P1]=max(r[P1],r[P2])           */
#define OP_OffsetLimit   145 /* synopsis: if r[P1]>0 then r[P2]=r[P1]+max(0,r[P3]) else r[P2]=(-1) */
#define OP_AggStep0      146 /* synopsis: accum=r[P3] step(r[P2@P5])       */
#define OP_AggStep       147 /* synopsis: accum=r[P3] step(r[P2@P5])       */
#define OP_AggFinal      148 /* synopsis: accum=r[P1] N=P2                 */
#define OP_Expire        149
#define OP_TableLock     150 /* synopsis: iDb=P1 root=P2 write=P3          */
#define OP_VBegin        151
#define OP_VCreate       152
#define OP_VDestroy      153
#define OP_VOpen         154
#define OP_VColumn       155 /* synopsis: r[P3]=vcolumn(P2)                */
#define OP_VRename       156
#define OP_Pagecount     157
#define OP_MaxPgcnt      158
#define OP_CursorHint    159
#define OP_Noop          160
#define OP_Explain       161

/* Properties such as "out2" or "jump" that are specified in
** comments following the "case" for each opcode in the vdbe.c
** are encoded into bitvectors as follows:
*/
#define OPFLG_JUMP        0x01  /* jump:  P2 holds jmp target */
#define OPFLG_IN1         0x02  /* in1:   P1 is an input */

/*  64 */ 0x01, 0x01, 0x03, 0x03, 0x03, 0x01, 0x01, 0x01,\
/*  72 */ 0x02, 0x02, 0x08, 0x00, 0x10, 0x10, 0x10, 0x10,\
/*  80 */ 0x00, 0x10, 0x10, 0x00, 0x00, 0x10, 0x10, 0x00,\
/*  88 */ 0x00, 0x00, 0x00, 0x02, 0x02, 0x02, 0x00, 0x00,\
/*  96 */ 0x00, 0x10, 0x00, 0x00, 0x10, 0x10, 0x00, 0x00,\
/* 104 */ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,\
/* 112 */ 0x00, 0x10, 0x10, 0x00, 0x00, 0x00, 0x00, 0x00,\
/* 120 */ 0x00, 0x00, 0x10, 0x00, 0x04, 0x04, 0x00, 0x00,\
/* 128 */ 0x10, 0x10, 0x00, 0x00, 0x10, 0x10, 0x10, 0x00,\
/* 136 */ 0x00, 0x00, 0x00, 0x00, 0x00, 0x06, 0x10, 0x00,\
/* 144 */ 0x04, 0x1a, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,\
/* 152 */ 0x00, 0x00, 0x00, 0x00, 0x00, 0x10, 0x10, 0x00,\
/* 160 */ 0x00, 0x00,}

/* The sqlite3P2Values() routine is able to run faster if it knows
** the value of the largest JUMP opcode.  The smaller the maximum
** JUMP opcode the better, so the mkopcodeh.tcl script that
** generated this include file strives to group all JUMP opcodes
** together near the beginning of the list.
*/

SQLITE_PRIVATE void sqlite3VdbeChangeP2(Vdbe*, u32 addr, int P2);
SQLITE_PRIVATE void sqlite3VdbeChangeP3(Vdbe*, u32 addr, int P3);
SQLITE_PRIVATE void sqlite3VdbeChangeP5(Vdbe*, u8 P5);
SQLITE_PRIVATE void sqlite3VdbeJumpHere(Vdbe*, int addr);
SQLITE_PRIVATE int sqlite3VdbeChangeToNoop(Vdbe*, int addr);
SQLITE_PRIVATE int sqlite3VdbeDeletePriorOpcode(Vdbe*, u8 op);
SQLITE_PRIVATE void sqlite3VdbeChangeP4(Vdbe*, int addr, const char *zP4, int N);
SQLITE_PRIVATE void sqlite3VdbeAppendP4(Vdbe*, void *pP4, int p4type);
SQLITE_PRIVATE void sqlite3VdbeSetP4KeyInfo(Parse*, Index*);
SQLITE_PRIVATE void sqlite3VdbeUsesBtree(Vdbe*, int);
SQLITE_PRIVATE VdbeOp *sqlite3VdbeGetOp(Vdbe*, int);
SQLITE_PRIVATE int sqlite3VdbeMakeLabel(Vdbe*);
SQLITE_PRIVATE void sqlite3VdbeRunOnlyOnce(Vdbe*);
SQLITE_PRIVATE void sqlite3VdbeReusable(Vdbe*);
SQLITE_PRIVATE void sqlite3VdbeDelete(Vdbe*);

SQLITE_PRIVATE   char *sqlite3VdbeExpandSql(Vdbe*, const char*);
#endif
SQLITE_PRIVATE int sqlite3MemCompare(const Mem*, const Mem*, const CollSeq*);

SQLITE_PRIVATE void sqlite3VdbeRecordUnpack(KeyInfo*,int,const void*,UnpackedRecord*);
SQLITE_PRIVATE int sqlite3VdbeRecordCompare(int,const void*,UnpackedRecord*);
SQLITE_PRIVATE int sqlite3VdbeRecordCompareWithSkip(int, const void *, UnpackedRecord *, int);
SQLITE_PRIVATE UnpackedRecord *sqlite3VdbeAllocUnpackedRecord(KeyInfo*);

typedef int (*RecordCompare)(int,const void*,UnpackedRecord*);
SQLITE_PRIVATE RecordCompare sqlite3VdbeFindCompare(UnpackedRecord*);

#ifndef SQLITE_OMIT_TRIGGER
SQLITE_PRIVATE void sqlite3VdbeLinkSubProgram(Vdbe *, SubProgram *);
#endif

  Pager **ppPager,
  const char*,
  int,
  int,
  int,
  void(*)(DbPage*)
);
SQLITE_PRIVATE int sqlite3PagerClose(Pager *pPager, sqlite3*);
SQLITE_PRIVATE int sqlite3PagerReadFileheader(Pager*, int, unsigned char*);

/* Functions used to configure a Pager object. */
SQLITE_PRIVATE void sqlite3PagerSetBusyhandler(Pager*, int(*)(void *), void *);
SQLITE_PRIVATE int sqlite3PagerSetPagesize(Pager*, u32*, int);
#ifdef SQLITE_HAS_CODEC
SQLITE_PRIVATE void sqlite3PagerAlignReserve(Pager*,Pager*);

SQLITE_PRIVATE int sqlite3PagerCommitPhaseTwo(Pager*);
SQLITE_PRIVATE int sqlite3PagerRollback(Pager*);
SQLITE_PRIVATE int sqlite3PagerOpenSavepoint(Pager *pPager, int n);
SQLITE_PRIVATE int sqlite3PagerSavepoint(Pager *pPager, int op, int iSavepoint);
SQLITE_PRIVATE int sqlite3PagerSharedLock(Pager *pPager);

#ifndef SQLITE_OMIT_WAL
SQLITE_PRIVATE   int sqlite3PagerCheckpoint(Pager *pPager, sqlite3*, int, int*, int*);
SQLITE_PRIVATE   int sqlite3PagerWalSupported(Pager *pPager);
SQLITE_PRIVATE   int sqlite3PagerWalCallback(Pager *pPager);
SQLITE_PRIVATE   int sqlite3PagerOpenWal(Pager *pPager, int *pisOpen);
SQLITE_PRIVATE   int sqlite3PagerCloseWal(Pager *pPager, sqlite3*);
SQLITE_PRIVATE   int sqlite3PagerUseWal(Pager *pPager);
# ifdef SQLITE_ENABLE_SNAPSHOT
SQLITE_PRIVATE   int sqlite3PagerSnapshotGet(Pager *pPager, sqlite3_snapshot **ppSnapshot);
SQLITE_PRIVATE   int sqlite3PagerSnapshotOpen(Pager *pPager, sqlite3_snapshot *pSnapshot);
SQLITE_PRIVATE   int sqlite3PagerSnapshotRecover(Pager *pPager);
# endif
#else
# define sqlite3PagerUseWal(x) 0
#endif

#ifdef SQLITE_ENABLE_ZIPVFS
SQLITE_PRIVATE   int sqlite3PagerWalFramesize(Pager *pPager);

#define SQLITE_EnableTrigger  0x01000000  /* True to enable triggers */
#define SQLITE_DeferFKs       0x02000000  /* Defer all FK constraints */
#define SQLITE_QueryOnly      0x04000000  /* Disable database changes */
#define SQLITE_VdbeEQP        0x08000000  /* Debug EXPLAIN QUERY PLAN */
#define SQLITE_Vacuum         0x10000000  /* Currently in a VACUUM */
#define SQLITE_CellSizeCk     0x20000000  /* Check btree cell sizes on load */
#define SQLITE_Fts3Tokenizer  0x40000000  /* Enable fts3_tokenizer(2) */
#define SQLITE_NoCkptOnClose  0x80000000  /* No checkpoint on close()/DETACH */


/*
** Bits of the sqlite3.dbOptFlags field that are used by the
** sqlite3_test_control(SQLITE_TESTCTRL_OPTIMIZATIONS,...) interface to
** selectively disable various optimizations.
*/

#define SQLITE_Stat34         0x0800   /* Use STAT3 or STAT4 data */
#define SQLITE_CursorHints    0x2000   /* Add OP_CursorHint opcodes */
#define SQLITE_AllOpts        0xffff   /* All optimizations */

/*
** Macros for testing whether or not optimizations are enabled or disabled.
*/

#define OptimizationDisabled(db, mask)  (((db)->dbOptFlags&(mask))!=0)
#define OptimizationEnabled(db, mask)   (((db)->dbOptFlags&(mask))==0)





/*
** Return true if it OK to factor constant expressions into the initialization
** code. The argument is a Parse object for the code generator.
*/
#define ConstFactorOk(P) ((P)->okConstFactor)

  Index *pIndex;       /* List of SQL indexes on this table. */
  Select *pSelect;     /* NULL for tables.  Points to definition if a view. */
  FKey *pFKey;         /* Linked list of all foreign keys in this table */
  char *zColAff;       /* String defining the affinity of each column */
  ExprList *pCheck;    /* All CHECK constraints */
                       /*   ... also used as column name list in a VIEW */
  int tnum;            /* Root BTree page for this table */
  u32 nTabRef;         /* Number of pointers to this Table */
  i16 iPKey;           /* If not negative, use aCol[iPKey] as the rowid */
  i16 nCol;            /* Number of columns in this table */

  LogEst nRowLogEst;   /* Estimated rows in table - from sqlite_stat1 table */
  LogEst szTabRow;     /* Estimated size of each table row in bytes */
#ifdef SQLITE_ENABLE_COSTMULT
  LogEst costMult;     /* Cost multiplier for using this table */
#endif
  u8 tabFlags;         /* Mask of TF_* values */
  u8 keyConf;          /* What to do in case of uniqueness conflict on iPKey */

  ** each recursion.  The boundary between these two regions is determined
  ** using offsetof(Parse,sLastToken) so the sLastToken field must be the
  ** first field in the recursive region.
  ************************************************************************/

  Token sLastToken;       /* The last token parsed */
  ynVar nVar;               /* Number of '?' variables seen in the SQL so far */

  u8 iPkSortOrder;          /* ASC or DESC for INTEGER PRIMARY KEY */
  u8 explain;               /* True if the EXPLAIN flag is found on the query */
#ifndef SQLITE_OMIT_VIRTUALTABLE
  u8 declareVtab;           /* True if inside sqlite3_declare_vtab() */
  int nVtabLock;            /* Number of virtual tables to lock */
#endif
  int nHeight;              /* Expression tree height of current sub-select */
#ifndef SQLITE_OMIT_EXPLAIN
  int iSelectId;            /* ID of current select for EXPLAIN output */
  int iNextSelectId;        /* Next available select ID for EXPLAIN output */
#endif
  VList *pVList;            /* Mapping between variable names and numbers */
  Vdbe *pReprepare;         /* VM being reprepared (sqlite3Reprepare()) */
  const char *zTail;        /* All SQL text past the last semicolon parsed */
  Table *pNewTable;         /* A table being constructed by CREATE TABLE */
  Trigger *pNewTrigger;     /* Trigger under construct by a CREATE TRIGGER */
  const char *zAuthContext; /* The 6th parameter to db->xAuth callbacks */
#ifndef SQLITE_OMIT_VIRTUALTABLE
  Token sArg;               /* Complete text of a module argument */

#ifdef SQLITE_VDBE_COVERAGE
  /* The following callback (if not NULL) is invoked on every VDBE branch
  ** operation.  Set the callback using SQLITE_TESTCTRL_VDBE_COVERAGE.
  */
  void (*xVdbeBranch)(void*,int iSrcLine,u8 eThis,u8 eMx);  /* Callback */
  void *pVdbeBranchArg;                                     /* 1st argument */
#endif
#ifndef SQLITE_UNTESTABLE
  int (*xTestCallback)(int);        /* Invoked by sqlite3FaultSim() */
#endif
  int bLocaltimeFault;              /* True to fail localtime() calls */
  int iOnceResetThreshold;          /* When to reset OP_Once counters */
};

/*

SQLITE_PRIVATE int sqlite3MallocSize(void*);
SQLITE_PRIVATE int sqlite3DbMallocSize(sqlite3*, void*);
SQLITE_PRIVATE void *sqlite3ScratchMalloc(int);
SQLITE_PRIVATE void sqlite3ScratchFree(void*);
SQLITE_PRIVATE void *sqlite3PageMalloc(int);
SQLITE_PRIVATE void sqlite3PageFree(void*);
SQLITE_PRIVATE void sqlite3MemSetDefault(void);
#ifndef SQLITE_UNTESTABLE
SQLITE_PRIVATE void sqlite3BenignMallocHooks(void (*)(void), void (*)(void));
#endif
SQLITE_PRIVATE int sqlite3HeapNearlyFull(void);

/*
** On systems with ample stack space and that support alloca(), make
** use of alloca() to obtain space for large automatic objects.  By default,

SQLITE_PRIVATE void sqlite3ClearTempRegCache(Parse*);
#ifdef SQLITE_DEBUG
SQLITE_PRIVATE int sqlite3NoTempsInRange(Parse*,int,int);
#endif
SQLITE_PRIVATE Expr *sqlite3ExprAlloc(sqlite3*,int,const Token*,int);
SQLITE_PRIVATE Expr *sqlite3Expr(sqlite3*,int,const char*);
SQLITE_PRIVATE void sqlite3ExprAttachSubtrees(sqlite3*,Expr*,Expr*,Expr*);
SQLITE_PRIVATE Expr *sqlite3PExpr(Parse*, int, Expr*, Expr*);
SQLITE_PRIVATE void sqlite3PExprAddSelect(Parse*, Expr*, Select*);
SQLITE_PRIVATE Expr *sqlite3ExprAnd(sqlite3*,Expr*, Expr*);
SQLITE_PRIVATE Expr *sqlite3ExprFunction(Parse*,ExprList*, Token*);
SQLITE_PRIVATE void sqlite3ExprAssignVarNumber(Parse*, Expr*, u32);
SQLITE_PRIVATE void sqlite3ExprDelete(sqlite3*, Expr*);
SQLITE_PRIVATE ExprList *sqlite3ExprListAppend(Parse*,ExprList*,Expr*);
SQLITE_PRIVATE ExprList *sqlite3ExprListAppendVector(Parse*,ExprList*,IdList*,Expr*);
SQLITE_PRIVATE void sqlite3ExprListSetSortOrder(ExprList*,int);
SQLITE_PRIVATE void sqlite3ExprListSetName(Parse*,ExprList*,Token*,int);
SQLITE_PRIVATE void sqlite3ExprListSetSpan(Parse*,ExprList*,ExprSpan*);
SQLITE_PRIVATE void sqlite3ExprListDelete(sqlite3*, ExprList*);
SQLITE_PRIVATE u32 sqlite3ExprListFlags(const ExprList*);
SQLITE_PRIVATE int sqlite3Init(sqlite3*, char**);
SQLITE_PRIVATE int sqlite3InitCallback(void*, int, char**, char**);
SQLITE_PRIVATE void sqlite3Pragma(Parse*,Token*,Token*,Token*,int);
#ifndef SQLITE_OMIT_VIRTUALTABLE
SQLITE_PRIVATE Module *sqlite3PragmaVtabRegister(sqlite3*,const char *zName);
#endif
SQLITE_PRIVATE void sqlite3ResetAllSchemasOfConnection(sqlite3*);
SQLITE_PRIVATE void sqlite3ResetOneSchema(sqlite3*,int);
SQLITE_PRIVATE void sqlite3CollapseDatabaseArray(sqlite3*);
SQLITE_PRIVATE void sqlite3CommitInternalChanges(sqlite3*);
SQLITE_PRIVATE void sqlite3DeleteColumnNames(sqlite3*,Table*);
SQLITE_PRIVATE int sqlite3ColumnsFromExprList(Parse*,ExprList*,i16*,Column**);
SQLITE_PRIVATE void sqlite3SelectAddColumnTypeAndCollation(Parse*,Table*,Select*);

SQLITE_PRIVATE void sqlite3AddDefaultValue(Parse*,ExprSpan*);
SQLITE_PRIVATE void sqlite3AddCollateType(Parse*, Token*);
SQLITE_PRIVATE void sqlite3EndTable(Parse*,Token*,Token*,u8,Select*);
SQLITE_PRIVATE int sqlite3ParseUri(const char*,const char*,unsigned int*,
                    sqlite3_vfs**,char**,char **);
SQLITE_PRIVATE Btree *sqlite3DbNameToBtree(sqlite3*,const char*);

#ifdef SQLITE_UNTESTABLE
# define sqlite3FaultSim(X) SQLITE_OK
#else
SQLITE_PRIVATE   int sqlite3FaultSim(int);
#endif

SQLITE_PRIVATE Bitvec *sqlite3BitvecCreate(u32);
SQLITE_PRIVATE int sqlite3BitvecTest(Bitvec*, u32);
SQLITE_PRIVATE int sqlite3BitvecTestNotNull(Bitvec*, u32);
SQLITE_PRIVATE int sqlite3BitvecSet(Bitvec*, u32);
SQLITE_PRIVATE void sqlite3BitvecClear(Bitvec*, u32, void*);
SQLITE_PRIVATE void sqlite3BitvecDestroy(Bitvec*);
SQLITE_PRIVATE u32 sqlite3BitvecSize(Bitvec*);
#ifndef SQLITE_UNTESTABLE
SQLITE_PRIVATE int sqlite3BitvecBuiltinTest(int,int*);
#endif

SQLITE_PRIVATE RowSet *sqlite3RowSetInit(sqlite3*, void*, unsigned int);
SQLITE_PRIVATE void sqlite3RowSetClear(RowSet*);
SQLITE_PRIVATE void sqlite3RowSetInsert(RowSet*, i64);
SQLITE_PRIVATE int sqlite3RowSetTest(RowSet*, int iBatch, i64);

SQLITE_PRIVATE int sqlite3ExprCodeTemp(Parse*, Expr*, int*);
SQLITE_PRIVATE int sqlite3ExprCodeTarget(Parse*, Expr*, int);
SQLITE_PRIVATE void sqlite3ExprCodeAndCache(Parse*, Expr*, int);
SQLITE_PRIVATE int sqlite3ExprCodeExprList(Parse*, ExprList*, int, int, u8);
#define SQLITE_ECEL_DUP      0x01  /* Deep, not shallow copies */
#define SQLITE_ECEL_FACTOR   0x02  /* Factor out constant terms */
#define SQLITE_ECEL_REF      0x04  /* Use ExprList.u.x.iOrderByCol */
#define SQLITE_ECEL_OMITREF  0x08  /* Omit if ExprList.u.x.iOrderByCol */
SQLITE_PRIVATE void sqlite3ExprIfTrue(Parse*, Expr*, int, int);
SQLITE_PRIVATE void sqlite3ExprIfFalse(Parse*, Expr*, int, int);
SQLITE_PRIVATE void sqlite3ExprIfFalseDup(Parse*, Expr*, int, int);
SQLITE_PRIVATE Table *sqlite3FindTable(sqlite3*,const char*, const char*);
#define LOCATE_VIEW    0x01
#define LOCATE_NOERR   0x02
SQLITE_PRIVATE Table *sqlite3LocateTable(Parse*,u32 flags,const char*, const char*);

SQLITE_PRIVATE int sqlite3ExprListCompare(ExprList*, ExprList*, int);
SQLITE_PRIVATE int sqlite3ExprImpliesExpr(Expr*, Expr*, int);
SQLITE_PRIVATE void sqlite3ExprAnalyzeAggregates(NameContext*, Expr*);
SQLITE_PRIVATE void sqlite3ExprAnalyzeAggList(NameContext*,ExprList*);
SQLITE_PRIVATE int sqlite3ExprCoveredByIndex(Expr*, int iCur, Index *pIdx);
SQLITE_PRIVATE int sqlite3FunctionUsesThisSrc(Expr*, SrcList*);
SQLITE_PRIVATE Vdbe *sqlite3GetVdbe(Parse*);
#ifndef SQLITE_UNTESTABLE
SQLITE_PRIVATE void sqlite3PrngSaveState(void);
SQLITE_PRIVATE void sqlite3PrngRestoreState(void);
#endif
SQLITE_PRIVATE void sqlite3RollbackAll(sqlite3*,int);
SQLITE_PRIVATE void sqlite3CodeVerifySchema(Parse*, int);
SQLITE_PRIVATE void sqlite3CodeVerifyNamedSchema(Parse*, const char *zDb);
SQLITE_PRIVATE void sqlite3BeginTransaction(Parse*, int);

SQLITE_PRIVATE LogEst sqlite3LogEstFromDouble(double);
#endif
#if defined(SQLITE_ENABLE_STMT_SCANSTATUS) || \
    defined(SQLITE_ENABLE_STAT3_OR_STAT4) || \
    defined(SQLITE_EXPLAIN_ESTIMATED_ROWS)
SQLITE_PRIVATE u64 sqlite3LogEstToInt(LogEst);
#endif
SQLITE_PRIVATE VList *sqlite3VListAdd(sqlite3*,VList*,const char*,int,int);
SQLITE_PRIVATE const char *sqlite3VListNumToName(VList*,int);
SQLITE_PRIVATE int sqlite3VListNameToNum(VList*,const char*,int);

/*
** Routines to read and write variable-length integers.  These used to
** be defined locally, but now we use the varint routines in the util.c
** file.
*/
SQLITE_PRIVATE int sqlite3PutVarint(unsigned char*, u64);

SQLITE_PRIVATE    int sqlite3VtabCommit(sqlite3 *db);
SQLITE_PRIVATE    void sqlite3VtabLock(VTable *);
SQLITE_PRIVATE    void sqlite3VtabUnlock(VTable *);
SQLITE_PRIVATE    void sqlite3VtabUnlockList(sqlite3*);
SQLITE_PRIVATE    int sqlite3VtabSavepoint(sqlite3 *, int, int);
SQLITE_PRIVATE    void sqlite3VtabImportErrmsg(Vdbe*, sqlite3_vtab*);
SQLITE_PRIVATE    VTable *sqlite3GetVTable(sqlite3*, Table*);
SQLITE_PRIVATE    Module *sqlite3VtabCreateModule(
     sqlite3*,
     const char*,
     const sqlite3_module*,
     void*,
     void(*)(void*)
   );
#  define sqlite3VtabInSync(db) ((db)->nVTrans>0 && (db)->aVTrans==0)
#endif
SQLITE_PRIVATE int sqlite3VtabEponymousTableInit(Parse*,Module*);
SQLITE_PRIVATE void sqlite3VtabEponymousTableClear(sqlite3*,Module*);
SQLITE_PRIVATE void sqlite3VtabMakeWritable(Parse*,Table*);
SQLITE_PRIVATE void sqlite3VtabBeginParse(Parse*, Token*, Token*, Token*, int);
SQLITE_PRIVATE void sqlite3VtabFinishParse(Parse*, Token*);

** Available fault injectors.  Should be numbered beginning with 0.
*/
#define SQLITE_FAULTINJECTOR_MALLOC     0
#define SQLITE_FAULTINJECTOR_COUNT      1

/*
** The interface to the code in fault.c used for identifying "benign"
** malloc failures. This is only present if SQLITE_UNTESTABLE
** is not defined.
*/
#ifndef SQLITE_UNTESTABLE
SQLITE_PRIVATE   void sqlite3BeginBenignMalloc(void);
SQLITE_PRIVATE   void sqlite3EndBenignMalloc(void);
#else
  #define sqlite3BeginBenignMalloc()
  #define sqlite3EndBenignMalloc()
#endif

SQLITE_PRIVATE int sqlite3DbstatRegister(sqlite3*);
#endif

SQLITE_PRIVATE int sqlite3ExprVectorSize(Expr *pExpr);
SQLITE_PRIVATE int sqlite3ExprIsVector(Expr *pExpr);
SQLITE_PRIVATE Expr *sqlite3VectorFieldSubexpr(Expr*, int);
SQLITE_PRIVATE Expr *sqlite3ExprForVectorField(Parse*,Expr*,int);
SQLITE_PRIVATE void sqlite3VectorErrorMsg(Parse*, Expr*);

#endif /* SQLITEINT_H */

/************** End of sqliteInt.h *******************************************/
/************** Begin file global.c ******************************************/
/*
** 2008 June 13

   SQLITE_DEFAULT_MEMSTATUS,  /* bMemstat */
   1,                         /* bCoreMutex */
   SQLITE_THREADSAFE==1,      /* bFullMutex */
   SQLITE_USE_URI,            /* bOpenUri */
   SQLITE_ALLOW_COVERING_INDEX_SCAN,   /* bUseCis */
   0x7ffffffe,                /* mxStrlen */
   0,                         /* neverCorrupt */
   512,                       /* szLookaside */
   125,                       /* nLookaside */
   SQLITE_STMTJRNL_SPILL,     /* nStmtSpill */
   {0,0,0,0,0,0,0,0},         /* m */
   {0,0,0,0,0,0,0,0,0},       /* mutex */
   {0,0,0,0,0,0,0,0,0,0,0,0,0},/* pcache2 */
   (void*)0,                  /* pHeap */
   0,                         /* nHeap */
   0, 0,                      /* mnHeap, mxHeap */

   0,                         /* xSqllog */
   0,                         /* pSqllogArg */
#endif
#ifdef SQLITE_VDBE_COVERAGE
   0,                         /* xVdbeBranch */
   0,                         /* pVbeBranchArg */
#endif
#ifndef SQLITE_UNTESTABLE
   0,                         /* xTestCallback */
#endif
   0,                         /* bLocaltimeFault */
   0x7ffffffe                 /* iOnceResetThreshold */
};

/*

  "DEBUG",
#endif
#if SQLITE_DEFAULT_LOCKING_MODE
  "DEFAULT_LOCKING_MODE=" CTIMEOPT_VAL(SQLITE_DEFAULT_LOCKING_MODE),
#endif
#if defined(SQLITE_DEFAULT_MMAP_SIZE) && !defined(SQLITE_DEFAULT_MMAP_SIZE_xc)
  "DEFAULT_MMAP_SIZE=" CTIMEOPT_VAL(SQLITE_DEFAULT_MMAP_SIZE),
#endif
#if SQLITE_DIRECT_OVERFLOW_READ
  "DIRECT_OVERFLOW_READ",
#endif
#if SQLITE_DISABLE_DIRSYNC
  "DISABLE_DIRSYNC",
#endif
#if SQLITE_DISABLE_LFS
  "DISABLE_LFS",
#endif

#endif
#if SQLITE_ENABLE_UNLOCK_NOTIFY
  "ENABLE_UNLOCK_NOTIFY",
#endif
#if SQLITE_ENABLE_UPDATE_DELETE_LIMIT
  "ENABLE_UPDATE_DELETE_LIMIT",
#endif
#if defined(SQLITE_ENABLE_URI_00_ERROR)
  "ENABLE_URI_00_ERROR",
#endif
#if SQLITE_HAS_CODEC
  "HAS_CODEC",
#endif
#if HAVE_ISNAN || SQLITE_HAVE_ISNAN
  "HAVE_ISNAN",
#endif
#if SQLITE_HOMEGROWN_RECURSIVE_MUTEX

#endif
#if SQLITE_OMIT_BLOB_LITERAL
  "OMIT_BLOB_LITERAL",
#endif
#if SQLITE_OMIT_BTREECOUNT
  "OMIT_BTREECOUNT",
#endif



#if SQLITE_OMIT_CAST
  "OMIT_CAST",
#endif
#if SQLITE_OMIT_CHECK
  "OMIT_CHECK",
#endif
#if SQLITE_OMIT_COMPLETE

  "TEMP_STORE=" CTIMEOPT_VAL(SQLITE_TEMP_STORE),
#endif
#if SQLITE_TEST
  "TEST",
#endif
#if defined(SQLITE_THREADSAFE)
  "THREADSAFE=" CTIMEOPT_VAL(SQLITE_THREADSAFE),
#endif
#if SQLITE_UNTESTABLE
  "UNTESTABLE"
#endif
#if SQLITE_USE_ALLOCA
  "USE_ALLOCA",
#endif
#if SQLITE_USER_AUTHENTICATION
  "USER_AUTHENTICATION",
#endif

**          -  On either an index or a table
**      * A sorter
**      * A virtual table
**      * A one-row "pseudotable" stored in a single register
*/
typedef struct VdbeCursor VdbeCursor;
struct VdbeCursor {
  u8 eCurType;            /* One of the CURTYPE_* values above */
  i8 iDb;                 /* Index of cursor database in db->aDb[] (or -1) */
  u8 nullRow;             /* True if pointing to a row with no data */
  u8 deferredMoveto;      /* A call to sqlite3BtreeMoveto() is needed */
  u8 isTable;             /* True for rowid tables.  False for indexes */
#ifdef SQLITE_DEBUG
  u8 seekOp;              /* Most recent seek operation on this cursor */
  u8 wrFlag;              /* The wrFlag argument to sqlite3BtreeCursor() */
#endif
  Bool isEphemeral:1;     /* True for an ephemeral table */
  Bool useRandomRowid:1;  /* Generate new record numbers semi-randomly */
  Bool isOrdered:1;       /* True if the table is not BTREE_UNORDERED */
  Btree *pBtx;            /* Separate file holding temporary table */
  i64 seqCount;           /* Sequence counter */
  int *aAltMap;           /* Mapping from table to index column numbers */

  /* Cached OP_Column parse information is only valid if cacheStatus matches
  ** Vdbe.cacheCtr.  Vdbe.cacheCtr will never take on the value of
  ** CACHE_STALE (0) and so setting cacheStatus=CACHE_STALE guarantees that
  ** the cache is out of date. */
  u32 cacheStatus;        /* Cache is valid if this matches Vdbe.cacheCtr */
  int seekResult;         /* Result of previous sqlite3BtreeMoveto() or 0
                          ** if there have been no prior seeks on the cursor. */
  /* NB: seekResult does not distinguish between "no seeks have ever occurred
  ** on this cursor" and "the most recent seek was an exact match". */

  /* When a new VdbeCursor is allocated, only the fields above are zeroed.
  ** The fields that follow are uninitialized, and must be individually
  ** initialized prior to first use. */
  VdbeCursor *pAltCursor; /* Associated index cursor from which to read */
  union {
    BtCursor *pCursor;          /* CURTYPE_BTREE.  Btree cursor */
    sqlite3_vtab_cursor *pVCur; /* CURTYPE_VTAB.   Vtab cursor */
    int pseudoTableReg;         /* CURTYPE_PSEUDO. Reg holding content. */
    VdbeSorter *pSorter;        /* CURTYPE_SORTER. Sorter object */
  } uc;

  KeyInfo *pKeyInfo;      /* Info about index keys needed by index cursors */
  u32 iHdrOffset;         /* Offset to next unparsed byte of the header */
  Pgno pgnoRoot;          /* Root page of the open btree cursor */
  i16 nField;             /* Number of fields in the header */
  u16 nHdrParsed;         /* Number of header fields parsed so far */
  i64 movetoTarget;       /* Argument to the deferred sqlite3BtreeMoveto() */

  u32 *aOffset;           /* Pointer to aType[nField] */
  const u8 *aRow;         /* Data for the current row, if all on one page */
  u32 payloadSize;        /* Total number of bytes in the record */
  u32 szRow;              /* Byte available in aRow */
#ifdef SQLITE_ENABLE_COLUMN_USED_MASK
  u64 maskUsed;           /* Mask of columns used by this cursor */
#endif

















  /* 2*nField extra array elements allocated for aType[], beyond the one
  ** static element declared in the structure.  nField total array slots for
  ** aType[] and nField+1 array slots for aOffset[] */
  u32 aType[1];           /* Type values record decode.  MUST BE LAST */
};


/*
** A value for VdbeCursor.cacheStatus that means the cache is always invalid.
*/
#define CACHE_STALE 0

** is really a pointer to an instance of this structure.
*/
struct Vdbe {
  sqlite3 *db;            /* The database connection that owns this statement */
  Vdbe *pPrev,*pNext;     /* Linked list of VDBEs with the same Vdbe.db */
  Parse *pParse;          /* Parsing context used to create this Vdbe */
  ynVar nVar;             /* Number of entries in aVar[] */

  u32 magic;              /* Magic number for sanity checking */
  int nMem;               /* Number of memory locations currently allocated */
  int nCursor;            /* Number of slots in apCsr[] */
  u32 cacheCtr;           /* VdbeCursor row cache generation counter */
  int pc;                 /* The program counter */
  int rc;                 /* Value to return */
  int nChange;            /* Number of db changes made since last reset */

  Mem *aMem;              /* The memory locations */
  Mem **apArg;            /* Arguments to currently executing user function */
  Mem *aColName;          /* Column names to return */
  Mem *pResultSet;        /* Pointer to an array of results */
  char *zErrMsg;          /* Error message written here */
  VdbeCursor **apCsr;     /* One element of this array for each open cursor */
  Mem *aVar;              /* Values for the OP_Variable opcode. */
  VList *pVList;          /* Name of variables */
#ifndef SQLITE_OMIT_TRACE
  i64 startTime;          /* Time when query started - used for profiling */
#endif
  int nOp;                /* Number of instructions in the program */
#ifdef SQLITE_DEBUG
  int rcApp;              /* errcode set by sqlite3_result_error_code() */
#endif

SQLITE_PRIVATE i64 sqlite3VdbeIntValue(Mem*);
SQLITE_PRIVATE int sqlite3VdbeMemIntegerify(Mem*);
SQLITE_PRIVATE double sqlite3VdbeRealValue(Mem*);
SQLITE_PRIVATE void sqlite3VdbeIntegerAffinity(Mem*);
SQLITE_PRIVATE int sqlite3VdbeMemRealify(Mem*);
SQLITE_PRIVATE int sqlite3VdbeMemNumerify(Mem*);
SQLITE_PRIVATE void sqlite3VdbeMemCast(Mem*,u8,u8);
SQLITE_PRIVATE int sqlite3VdbeMemFromBtree(BtCursor*,u32,u32,Mem*);
SQLITE_PRIVATE void sqlite3VdbeMemRelease(Mem *p);
SQLITE_PRIVATE int sqlite3VdbeMemFinalize(Mem*, FuncDef*);
SQLITE_PRIVATE const char *sqlite3OpcodeName(int);
SQLITE_PRIVATE int sqlite3VdbeMemGrow(Mem *pMem, int n, int preserve);
SQLITE_PRIVATE int sqlite3VdbeMemClearAndResize(Mem *pMem, int n);
SQLITE_PRIVATE int sqlite3VdbeCloseStatement(Vdbe *, int);
SQLITE_PRIVATE void sqlite3VdbeFrameDelete(VdbeFrame*);

#endif

/*
** A structure for holding a single date and time.
*/
typedef struct DateTime DateTime;
struct DateTime {
  sqlite3_int64 iJD;  /* The julian day number times 86400000 */
  int Y, M, D;        /* Year, month, and day */
  int h, m;           /* Hour and minutes */
  int tz;             /* Timezone offset in minutes */
  double s;           /* Seconds */
  char validJD;       /* True (1) if iJD is valid */
  char rawS;          /* Raw numeric value stored in s */
  char validYMD;      /* True (1) if Y,M,D are valid */
  char validHMS;      /* True (1) if h,m,s are valid */

  char validTZ;       /* True (1) if tz is valid */
  char tzSet;         /* Timezone was set explicitly */
  char isError;       /* An overflow has occurred */
};


/*
** Convert zDate into one or more integers according to the conversion
** specifier zFormat.
**

      }
      ms /= rScale;
    }
  }else{
    s = 0;
  }
  p->validJD = 0;
  p->rawS = 0;
  p->validHMS = 1;
  p->h = h;
  p->m = m;
  p->s = s + ms;
  if( parseTimezone(zDate, p) ) return 1;
  p->validTZ = (p->tz!=0)?1:0;
  return 0;
}

/*
** Put the DateTime object into its error state.
*/
static void datetimeError(DateTime *p){
  memset(p, 0, sizeof(*p));
  p->isError = 1;
}

/*
** Convert from YYYY-MM-DD HH:MM:SS to julian day.  We always assume
** that the YYYY-MM-DD is according to the Gregorian calendar.
**
** Reference:  Meeus page 61
*/
static void computeJD(DateTime *p){
  int Y, M, D, A, B, X1, X2;

  if( p->validJD ) return;
  if( p->validYMD ){
    Y = p->Y;
    M = p->M;
    D = p->D;
  }else{
    Y = 2000;  /* If no YMD specified, assume 2000-Jan-01 */
    M = 1;
    D = 1;
  }
  if( Y<-4713 || Y>9999 || p->rawS ){
    datetimeError(p);
    return;
  }
  if( M<=2 ){
    Y--;
    M += 12;
  }
  A = Y/100;
  B = 2 - A + (A/4);

  if( p->iJD>0 ){
    p->validJD = 1;
    return 0;
  }else{
    return 1;
  }
}

/*
** Input "r" is a numeric quantity which might be a julian day number,
** or the number of seconds since 1970.  If the value if r is within
** range of a julian day number, install it as such and set validJD.
** If the value is a valid unix timestamp, put it in p->s and set p->rawS.
*/
static void setRawDateNumber(DateTime *p, double r){
  p->s = r;
  p->rawS = 1;
  if( r>=0.0 && r<5373484.5 ){
    p->iJD = (sqlite3_int64)(r*86400000.0 + 0.5);
    p->validJD = 1;
  }
}

/*
** Attempt to parse the given string into a julian day number.  Return
** the number of errors.
**
** The following are acceptable forms for the input string:
**

  if( parseYyyyMmDd(zDate,p)==0 ){
    return 0;
  }else if( parseHhMmSs(zDate, p)==0 ){
    return 0;
  }else if( sqlite3StrICmp(zDate,"now")==0){
    return setDateTimeToCurrent(context, p);
  }else if( sqlite3AtoF(zDate, &r, sqlite3Strlen30(zDate), SQLITE_UTF8) ){
    setRawDateNumber(p, r);

    return 0;
  }
  return 1;
}

/* The julian day number for 9999-12-31 23:59:59.999 is 5373484.4999999.
** Multiplying this by 86400000 gives 464269060799999 as the maximum value
** for DateTime.iJD.
**
** But some older compilers (ex: gcc 4.2.1 on older Macs) cannot deal with 
** such a large integer literal, so we have to encode it.
*/
#define INT_464269060799999  ((((i64)0x1a640)<<32)|0x1072fdff)

/*
** Return TRUE if the given julian day number is within range.
**
** The input is the JulianDay times 86400000.
*/
static int validJulianDay(sqlite3_int64 iJD){
  return iJD>=0 && iJD<=INT_464269060799999;
}

/*
** Compute the Year, Month, and Day from the julian day number.
*/
static void computeYMD(DateTime *p){
  int Z, A, B, C, D, E, X1;
  if( p->validYMD ) return;
  if( !p->validJD ){
    p->Y = 2000;
    p->M = 1;
    p->D = 1;
  }else{
    assert( validJulianDay(p->iJD) );
    Z = (int)((p->iJD + 43200000)/86400000);
    A = (int)((Z - 1867216.25)/36524.25);
    A = Z + 1 + A - (A/4);
    B = A + 1524;
    C = (int)((B - 122.1)/365.25);
    D = (36525*(C&32767))/100;
    E = (int)((B-D)/30.6001);

  p->s = s/1000.0;
  s = (int)p->s;
  p->s -= s;
  p->h = s/3600;
  s -= p->h*3600;
  p->m = s/60;
  p->s += s - p->m*60;
  p->rawS = 0;
  p->validHMS = 1;
}

/*
** Compute both YMD and HMS
*/
static void computeYMD_HMS(DateTime *p){

#if !HAVE_LOCALTIME_R && !HAVE_LOCALTIME_S
  struct tm *pX;
#if SQLITE_THREADSAFE>0
  sqlite3_mutex *mutex = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER);
#endif
  sqlite3_mutex_enter(mutex);
  pX = localtime(t);
#ifndef SQLITE_UNTESTABLE
  if( sqlite3GlobalConfig.bLocaltimeFault ) pX = 0;
#endif
  if( pX ) *pTm = *pX;
  sqlite3_mutex_leave(mutex);
  rc = pX==0;
#else
#ifndef SQLITE_UNTESTABLE
  if( sqlite3GlobalConfig.bLocaltimeFault ) return 1;
#endif
#if HAVE_LOCALTIME_R
  rc = localtime_r(t, pTm)==0;
#else
  rc = localtime_s(pTm, t);
#endif /* HAVE_LOCALTIME_R */

  y.D = sLocal.tm_mday;
  y.h = sLocal.tm_hour;
  y.m = sLocal.tm_min;
  y.s = sLocal.tm_sec;
  y.validYMD = 1;
  y.validHMS = 1;
  y.validJD = 0;
  y.rawS = 0;
  y.validTZ = 0;
  y.isError = 0;
  computeJD(&y);
  *pRc = SQLITE_OK;
  return y.iJD - x.iJD;
}
#endif /* SQLITE_OMIT_LOCALTIME */

/*
** The following table defines various date transformations of the form
**
**            'NNN days'
**
** Where NNN is an arbitrary floating-point number and "days" can be one
** of several units of time.
*/
static const struct {
  u8 eType;           /* Transformation type code */
  u8 nName;           /* Length of th name */
  char *zName;        /* Name of the transformation */
  double rLimit;      /* Maximum NNN value for this transform */
  double rXform;      /* Constant used for this transform */
} aXformType[] = {
  { 0, 6, "second", 464269060800.0, 86400000.0/(24.0*60.0*60.0) },
  { 0, 6, "minute", 7737817680.0,   86400000.0/(24.0*60.0)      },
  { 0, 4, "hour",   128963628.0,    86400000.0/24.0             },
  { 0, 3, "day",    5373485.0,      86400000.0                  },
  { 1, 5, "month",  176546.0,       30.0*86400000.0             },
  { 2, 4, "year",   14713.0,        365.0*86400000.0            },
};

/*
** Process a modifier to a date-time stamp.  The modifiers are
** as follows:
**
**     NNN days
**     NNN hours

**     utc
**
** Return 0 on success and 1 if there is any kind of error. If the error
** is in a system call (i.e. localtime()), then an error message is written
** to context pCtx. If the error is an unrecognized modifier, no error is
** written to pCtx.
*/
static int parseModifier(
  sqlite3_context *pCtx,      /* Function context */
  const char *z,              /* The text of the modifier */
  int n,                      /* Length of zMod in bytes */
  DateTime *p                 /* The date/time value to be modified */
){
  int rc = 1;

  double r;



  switch(sqlite3UpperToLower[(u8)z[0]] ){



#ifndef SQLITE_OMIT_LOCALTIME
    case 'l': {
      /*    localtime
      **
      ** Assuming the current time value is UTC (a.k.a. GMT), shift it to
      ** show local time.
      */
      if( sqlite3_stricmp(z, "localtime")==0 ){
        computeJD(p);
        p->iJD += localtimeOffset(p, pCtx, &rc);
        clearYMD_HMS_TZ(p);
      }
      break;
    }
#endif
    case 'u': {
      /*
      **    unixepoch
      **
      ** Treat the current value of p->s as the number of
      ** seconds since 1970.  Convert to a real julian day number.
      */
      if( sqlite3_stricmp(z, "unixepoch")==0 && p->rawS ){
        r = p->s*1000.0 + 210866760000000.0;
        if( r>=0.0 && r<464269060800000.0 ){
          clearYMD_HMS_TZ(p);
          p->iJD = (sqlite3_int64)r;
          p->validJD = 1;
          p->rawS = 0;
          rc = 0;
        }
      }
#ifndef SQLITE_OMIT_LOCALTIME
      else if( sqlite3_stricmp(z, "utc")==0 ){
        if( p->tzSet==0 ){
          sqlite3_int64 c1;
          computeJD(p);
          c1 = localtimeOffset(p, pCtx, &rc);
          if( rc==SQLITE_OK ){
            p->iJD -= c1;
            clearYMD_HMS_TZ(p);

      /*
      **    weekday N
      **
      ** Move the date to the same time on the next occurrence of
      ** weekday N where 0==Sunday, 1==Monday, and so forth.  If the
      ** date is already on the appropriate weekday, this is a no-op.
      */
      if( sqlite3_strnicmp(z, "weekday ", 8)==0
               && sqlite3AtoF(&z[8], &r, sqlite3Strlen30(&z[8]), SQLITE_UTF8)
               && (n=(int)r)==r && n>=0 && r<7 ){
        sqlite3_int64 Z;
        computeYMD_HMS(p);
        p->validTZ = 0;
        p->validJD = 0;
        computeJD(p);

    case 's': {
      /*
      **    start of TTTTT
      **
      ** Move the date backwards to the beginning of the current day,
      ** or month or year.
      */
      if( sqlite3_strnicmp(z, "start of ", 9)!=0 ) break;
      z += 9;
      computeYMD(p);
      p->validHMS = 1;
      p->h = p->m = 0;
      p->s = 0.0;
      p->validTZ = 0;
      p->validJD = 0;
      if( sqlite3_stricmp(z,"month")==0 ){
        p->D = 1;
        rc = 0;
      }else if( sqlite3_stricmp(z,"year")==0 ){
        computeYMD(p);
        p->M = 1;
        p->D = 1;
        rc = 0;
      }else if( sqlite3_stricmp(z,"day")==0 ){
        rc = 0;
      }
      break;
    }
    case '+':
    case '-':
    case '0':
    case '1':
    case '2':
    case '3':
    case '4':
    case '5':
    case '6':
    case '7':
    case '8':
    case '9': {
      double rRounder;
      int i;
      for(n=1; z[n] && z[n]!=':' && !sqlite3Isspace(z[n]); n++){}
      if( !sqlite3AtoF(z, &r, n, SQLITE_UTF8) ){
        rc = 1;
        break;
      }
      if( z[n]==':' ){
        /* A modifier of the form (+|-)HH:MM:SS.FFF adds (or subtracts) the

        if( z[0]=='-' ) tx.iJD = -tx.iJD;
        computeJD(p);
        clearYMD_HMS_TZ(p);
        p->iJD += tx.iJD;
        rc = 0;
        break;
      }

      /* If control reaches this point, it means the transformation is
      ** one of the forms like "+NNN days".  */
      z += n;
      while( sqlite3Isspace(*z) ) z++;
      n = sqlite3Strlen30(z);
      if( n>10 || n<3 ) break;
      if( sqlite3UpperToLower[(u8)z[n-1]]=='s' ) n--;
      computeJD(p);
      rc = 1;
      rRounder = r<0 ? -0.5 : +0.5;
      for(i=0; i<ArraySize(aXformType); i++){
        if( aXformType[i].nName==n
         && sqlite3_strnicmp(aXformType[i].zName, z, n)==0

         && r>-aXformType[i].rLimit && r<aXformType[i].rLimit
        ){
          switch( aXformType[i].eType ){


            case 1: { /* Special processing to add months */
              int x;
              computeYMD_HMS(p);
              p->M += (int)r;
              x = p->M>0 ? (p->M-1)/12 : (p->M-12)/12;
              p->Y += x;
              p->M -= x*12;
              p->validJD = 0;

              r -= (int)r;
              break;

            }

            case 2: { /* Special processing to add years */
              int y = (int)r;
              computeYMD_HMS(p);
              p->Y += y;
              p->validJD = 0;
              r -= (int)r;
              break;
            }
          }
          computeJD(p);

          p->iJD += (sqlite3_int64)(r*aXformType[i].rXform + rRounder);
          rc = 0;
          break;
        }


      }
      clearYMD_HMS_TZ(p);
      break;
    }
    default: {
      break;
    }

*/
static int isDate(
  sqlite3_context *context, 
  int argc, 
  sqlite3_value **argv, 
  DateTime *p
){
  int i, n;
  const unsigned char *z;
  int eType;
  memset(p, 0, sizeof(*p));
  if( argc==0 ){
    return setDateTimeToCurrent(context, p);
  }
  if( (eType = sqlite3_value_type(argv[0]))==SQLITE_FLOAT
                   || eType==SQLITE_INTEGER ){
    setRawDateNumber(p, sqlite3_value_double(argv[0]));

  }else{
    z = sqlite3_value_text(argv[0]);
    if( !z || parseDateOrTime(context, (char*)z, p) ){
      return 1;
    }
  }
  for(i=1; i<argc; i++){
    z = sqlite3_value_text(argv[i]);
    n = sqlite3_value_bytes(argv[i]);
    if( z==0 || parseModifier(context, (char*)z, n, p) ) return 1;
  }
  computeJD(p);
  if( p->isError || !validJulianDay(p->iJD) ) return 1;
  return 0;
}


/*
** The following routines implement the various date and time functions
** of SQLite.

** is completely recoverable simply by not carrying out the resize. The 
** hash table will continue to function normally.  So a malloc failure 
** during a hash table resize is a benign fault.
*/

/* #include "sqliteInt.h" */

#ifndef SQLITE_UNTESTABLE

/*
** Global variables.
*/
typedef struct BenignMallocHooks BenignMallocHooks;
static SQLITE_WSD struct BenignMallocHooks {
  void (*xBenignBegin)(void);

SQLITE_PRIVATE void sqlite3EndBenignMalloc(void){
  wsdHooksInit;
  if( wsdHooks.xBenignEnd ){
    wsdHooks.xBenignEnd();
  }
}

#endif   /* #ifndef SQLITE_UNTESTABLE */

/************** End of fault.c ***********************************************/
/************** Begin file mem0.c ********************************************/
/*
** 2008 October 28
**
** The author disclaims copyright to this source code.  In place of

  nNew = sqlite3GlobalConfig.m.xRoundup((int)nBytes);
  if( nOld==nNew ){
    pNew = pOld;
  }else if( sqlite3GlobalConfig.bMemstat ){
    sqlite3_mutex_enter(mem0.mutex);
    sqlite3StatusHighwater(SQLITE_STATUS_MALLOC_SIZE, (int)nBytes);
    nDiff = nNew - nOld;
    if( nDiff>0 && sqlite3StatusValue(SQLITE_STATUS_MEMORY_USED) >= 
          mem0.alarmThreshold-nDiff ){
      sqlite3MallocAlarm(nDiff);
    }
    pNew = sqlite3GlobalConfig.m.xRealloc(pOld, nNew);
    if( pNew==0 && mem0.alarmThreshold>0 ){
      sqlite3MallocAlarm((int)nBytes);
      pNew = sqlite3GlobalConfig.m.xRealloc(pOld, nNew);

*/
SQLITE_PRIVATE char *sqlite3DbStrDup(sqlite3 *db, const char *z){
  char *zNew;
  size_t n;
  if( z==0 ){
    return 0;
  }
  n = strlen(z) + 1;

  zNew = sqlite3DbMallocRaw(db, n);
  if( zNew ){
    memcpy(zNew, z, n);
  }
  return zNew;
}
SQLITE_PRIVATE char *sqlite3DbStrNDup(sqlite3 *db, const char *z, u64 n){
  char *zNew;

SQLITE_PRIVATE void sqlite3StrAccumAppend(StrAccum *p, const char *z, int N){
  assert( z!=0 || N==0 );
  assert( p->zText!=0 || p->nChar==0 || p->accError );
  assert( N>=0 );
  assert( p->accError==0 || p->nAlloc==0 );
  if( p->nChar+N >= p->nAlloc ){
    enlargeAndAppend(p,z,N);
  }else if( N ){
    assert( p->zText );
    p->nChar += N;
    memcpy(&p->zText[p->nChar-N], z, N);
  }
}

/*
** Append the complete text of zero-terminated string z[] to the p string.
*/
SQLITE_PRIVATE void sqlite3StrAccumAppendAll(StrAccum *p, const char *z){
  sqlite3StrAccumAppend(p, z, sqlite3Strlen30(z));
}


/*
** Finish off a string by making sure it is zero-terminated.
** Return a pointer to the resulting string.  Return a NULL
** pointer if any kind of error was encountered.
*/
static SQLITE_NOINLINE char *strAccumFinishRealloc(StrAccum *p){
  assert( p->mxAlloc>0 && !isMalloced(p) );
  p->zText = sqlite3DbMallocRaw(p->db, p->nChar+1 );
  if( p->zText ){
    memcpy(p->zText, p->zBase, p->nChar+1);
    p->printfFlags |= SQLITE_PRINTF_MALLOCED;
  }else{
    setStrAccumError(p, STRACCUM_NOMEM);
  }
  return p->zText;
}
SQLITE_PRIVATE char *sqlite3StrAccumFinish(StrAccum *p){
  if( p->zText ){
    assert( (p->zText==p->zBase)==!isMalloced(p) );
    p->zText[p->nChar] = 0;
    if( p->mxAlloc>0 && !isMalloced(p) ){





      return strAccumFinishRealloc(p);

    }
  }
  return p->zText;
}

/*
** Reset an StrAccum string.  Reclaim all malloced memory.

    (void)SQLITE_MISUSE_BKPT;
    if( zBuf ) zBuf[0] = 0;
    return zBuf;
  }
#endif
  sqlite3StrAccumInit(&acc, 0, zBuf, n, 0);
  sqlite3VXPrintf(&acc, zFormat, ap);
  zBuf[acc.nChar] = 0;
  return zBuf;
}
SQLITE_API char *sqlite3_snprintf(int n, char *zBuf, const char *zFormat, ...){
  char *z;
  va_list ap;
  va_start(ap,zFormat);
  z = sqlite3_vsnprintf(n, zBuf, zFormat, ap);
  va_end(ap);

      sqlite3StrAccumAppend(&acc, p->bLine[i] ? "|   " : "    ", 4);
    }
    sqlite3StrAccumAppend(&acc, p->bLine[i] ? "|-- " : "'-- ", 4);
  }
  va_start(ap, zFormat);
  sqlite3VXPrintf(&acc, zFormat, ap);
  va_end(ap);
  assert( acc.nChar>0 );
  if( zBuf[acc.nChar-1]!='\n' ) sqlite3StrAccumAppend(&acc, "\n", 1);
  sqlite3StrAccumFinish(&acc);
  fprintf(stdout,"%s", zBuf);
  fflush(stdout);
}

/*

    wsdPrng.s[wsdPrng.j] = t;
    t += wsdPrng.s[wsdPrng.i];
    *(zBuf++) = wsdPrng.s[t];
  }while( --N );
  sqlite3_mutex_leave(mutex);
}

#ifndef SQLITE_UNTESTABLE
/*
** For testing purposes, we sometimes want to preserve the state of
** PRNG and restore the PRNG to its saved state at a later time, or
** to reset the PRNG to its initial state.  These routines accomplish
** those tasks.
**
** The sqlite3_test_control() interface calls these routines to

SQLITE_PRIVATE void sqlite3PrngRestoreState(void){
  memcpy(
    &GLOBAL(struct sqlite3PrngType, sqlite3Prng),
    &GLOBAL(struct sqlite3PrngType, sqlite3SavedPrng),
    sizeof(sqlite3Prng)
  );
}
#endif /* SQLITE_UNTESTABLE */

/************** End of random.c **********************************************/
/************** Begin file threads.c *****************************************/
/*
** 2012 July 21
**
** The author disclaims copyright to this source code.  In place of

**
** The intent of the integer argument is to let the fault simulator know
** which of multiple sqlite3FaultSim() calls has been hit.
**
** Return whatever integer value the test callback returns, or return
** SQLITE_OK if no test callback is installed.
*/
#ifndef SQLITE_UNTESTABLE
SQLITE_PRIVATE int sqlite3FaultSim(int iTest){
  int (*xCallback)(int) = sqlite3GlobalConfig.xTestCallback;
  return xCallback ? xCallback(iTest) : SQLITE_OK;
}
#endif

#ifndef SQLITE_OMIT_FLOATING_POINT

  /* If only SQLITE_ENABLE_STAT3_OR_STAT4 is on, then the largest input
  ** possible to this routine is 310, resulting in a maximum x of 31 */
  assert( x<=60 );
#endif
  return x>=3 ? (n+8)<<(x-3) : (n+8)>>(3-x);
}
#endif /* defined SCANSTAT or STAT4 or ESTIMATED_ROWS */

/*
** Add a new name/number pair to a VList.  This might require that the
** VList object be reallocated, so return the new VList.  If an OOM
** error occurs, the original VList returned and the
** db->mallocFailed flag is set.
**
** A VList is really just an array of integers.  To destroy a VList,
** simply pass it to sqlite3DbFree().
**
** The first integer is the number of integers allocated for the whole
** VList.  The second integer is the number of integers actually used.
** Each name/number pair is encoded by subsequent groups of 3 or more
** integers.
**
** Each name/number pair starts with two integers which are the numeric
** value for the pair and the size of the name/number pair, respectively.
** The text name overlays one or more following integers.  The text name
** is always zero-terminated.
**
** Conceptually:
**
**    struct VList {
**      int nAlloc;   // Number of allocated slots 
**      int nUsed;    // Number of used slots 
**      struct VListEntry {
**        int iValue;    // Value for this entry
**        int nSlot;     // Slots used by this entry
**        // ... variable name goes here
**      } a[0];
**    }
**
** During code generation, pointers to the variable names within the
** VList are taken.  When that happens, nAlloc is set to zero as an 
** indication that the VList may never again be enlarged, since the
** accompanying realloc() would invalidate the pointers.
*/
SQLITE_PRIVATE VList *sqlite3VListAdd(
  sqlite3 *db,           /* The database connection used for malloc() */
  VList *pIn,            /* The input VList.  Might be NULL */
  const char *zName,     /* Name of symbol to add */
  int nName,             /* Bytes of text in zName */
  int iVal               /* Value to associate with zName */
){
  int nInt;              /* number of sizeof(int) objects needed for zName */
  char *z;               /* Pointer to where zName will be stored */
  int i;                 /* Index in pIn[] where zName is stored */

  nInt = nName/4 + 3;
  assert( pIn==0 || pIn[0]>=3 );  /* Verify ok to add new elements */
  if( pIn==0 || pIn[1]+nInt > pIn[0] ){
    /* Enlarge the allocation */
    int nAlloc = (pIn ? pIn[0]*2 : 10) + nInt;
    VList *pOut = sqlite3DbRealloc(db, pIn, nAlloc*sizeof(int));
    if( pOut==0 ) return pIn;
    if( pIn==0 ) pOut[1] = 2;
    pIn = pOut;
    pIn[0] = nAlloc;
  }
  i = pIn[1];
  pIn[i] = iVal;
  pIn[i+1] = nInt;
  z = (char*)&pIn[i+2];
  pIn[1] = i+nInt;
  assert( pIn[1]<=pIn[0] );
  memcpy(z, zName, nName);
  z[nName] = 0;
  return pIn;
}

/*
** Return a pointer to the name of a variable in the given VList that
** has the value iVal.  Or return a NULL if there is no such variable in
** the list
*/
SQLITE_PRIVATE const char *sqlite3VListNumToName(VList *pIn, int iVal){
  int i, mx;
  if( pIn==0 ) return 0;
  mx = pIn[1];
  i = 2;
  do{
    if( pIn[i]==iVal ) return (char*)&pIn[i+2];
    i += pIn[i+1];
  }while( i<mx );
  return 0;
}

/*
** Return the number of the variable named zName, if it is in VList.
** or return 0 if there is no such variable.
*/
SQLITE_PRIVATE int sqlite3VListNameToNum(VList *pIn, const char *zName, int nName){
  int i, mx;
  if( pIn==0 ) return 0;
  mx = pIn[1];
  i = 2;
  do{
    const char *z = (const char*)&pIn[i+2];
    if( strncmp(z,zName,nName)==0 && z[nName]==0 ) return pIn[i];
    i += pIn[i+1];
  }while( i<mx );
  return 0;
}

/************** End of util.c ************************************************/
/************** Begin file hash.c ********************************************/
/*
** 2001 September 22
**
** The author disclaims copyright to this source code.  In place of

    /*  60 */ "IdxLT"            OpHelp("key=r[P3@P4]"),
    /*  61 */ "IdxGE"            OpHelp("key=r[P3@P4]"),
    /*  62 */ "RowSetRead"       OpHelp("r[P3]=rowset(P1)"),
    /*  63 */ "RowSetTest"       OpHelp("if r[P3] in rowset(P1) goto P2"),
    /*  64 */ "Program"          OpHelp(""),
    /*  65 */ "FkIfZero"         OpHelp("if fkctr[P1]==0 goto P2"),
    /*  66 */ "IfPos"            OpHelp("if r[P1]>0 then r[P1]-=P3, goto P2"),
    /*  67 */ "IfNotZero"        OpHelp("if r[P1]!=0 then r[P1]--, goto P2"),
    /*  68 */ "DecrJumpZero"     OpHelp("if (--r[P1])==0 goto P2"),
    /*  69 */ "IncrVacuum"       OpHelp(""),
    /*  70 */ "VNext"            OpHelp(""),
    /*  71 */ "Init"             OpHelp("Start at P2"),
    /*  72 */ "Return"           OpHelp(""),
    /*  73 */ "EndCoroutine"     OpHelp(""),
    /*  74 */ "HaltIfNull"       OpHelp("if r[P3]=null halt"),

    /* 114 */ "NewRowid"         OpHelp("r[P2]=rowid"),
    /* 115 */ "Insert"           OpHelp("intkey=r[P3] data=r[P2]"),
    /* 116 */ "InsertInt"        OpHelp("intkey=P3 data=r[P2]"),
    /* 117 */ "Delete"           OpHelp(""),
    /* 118 */ "ResetCount"       OpHelp(""),
    /* 119 */ "SorterCompare"    OpHelp("if key(P1)!=trim(r[P3],P4) goto P2"),
    /* 120 */ "SorterData"       OpHelp("r[P2]=data"),

    /* 121 */ "RowData"          OpHelp("r[P2]=data"),
    /* 122 */ "Rowid"            OpHelp("r[P2]=rowid"),
    /* 123 */ "NullRow"          OpHelp(""),
    /* 124 */ "SorterInsert"     OpHelp("key=r[P2]"),
    /* 125 */ "IdxInsert"        OpHelp("key=r[P2]"),
    /* 126 */ "IdxDelete"        OpHelp("key=r[P2@P3]"),
    /* 127 */ "Seek"             OpHelp("Move P3 to P1.rowid"),
    /* 128 */ "IdxRowid"         OpHelp("r[P2]=rowid"),
    /* 129 */ "Destroy"          OpHelp(""),
    /* 130 */ "Clear"            OpHelp(""),
    /* 131 */ "ResetSorter"      OpHelp(""),
    /* 132 */ "Real"             OpHelp("r[P2]=P4"),

    /* 133 */ "CreateIndex"      OpHelp("r[P2]=root iDb=P1"),
    /* 134 */ "CreateTable"      OpHelp("r[P2]=root iDb=P1"),
    /* 135 */ "ParseSchema"      OpHelp(""),
    /* 136 */ "LoadAnalysis"     OpHelp(""),
    /* 137 */ "DropTable"        OpHelp(""),
    /* 138 */ "DropIndex"        OpHelp(""),
    /* 139 */ "DropTrigger"      OpHelp(""),
    /* 140 */ "IntegrityCk"      OpHelp(""),
    /* 141 */ "RowSetAdd"        OpHelp("rowset(P1)=r[P2]"),
    /* 142 */ "Param"            OpHelp(""),
    /* 143 */ "FkCounter"        OpHelp("fkctr[P1]+=P2"),
    /* 144 */ "MemMax"           OpHelp("r[P1]=max(r[P1],r[P2])"),
    /* 145 */ "OffsetLimit"      OpHelp("if r[P1]>0 then r[P2]=r[P1]+max(0,r[P3]) else r[P2]=(-1)"),
    /* 146 */ "AggStep0"         OpHelp("accum=r[P3] step(r[P2@P5])"),
    /* 147 */ "AggStep"          OpHelp("accum=r[P3] step(r[P2@P5])"),
    /* 148 */ "AggFinal"         OpHelp("accum=r[P1] N=P2"),
    /* 149 */ "Expire"           OpHelp(""),
    /* 150 */ "TableLock"        OpHelp("iDb=P1 root=P2 write=P3"),
    /* 151 */ "VBegin"           OpHelp(""),
    /* 152 */ "VCreate"          OpHelp(""),
    /* 153 */ "VDestroy"         OpHelp(""),
    /* 154 */ "VOpen"            OpHelp(""),
    /* 155 */ "VColumn"          OpHelp("r[P3]=vcolumn(P2)"),
    /* 156 */ "VRename"          OpHelp(""),
    /* 157 */ "Pagecount"        OpHelp(""),
    /* 158 */ "MaxPgcnt"         OpHelp(""),
    /* 159 */ "CursorHint"       OpHelp(""),
    /* 160 */ "Noop"             OpHelp(""),
    /* 161 */ "Explain"          OpHelp(""),
  };
  return azName[i];
}
#endif

/************** End of opcodes.c *********************************************/
/************** Begin file os_unix.c *****************************************/

** to locate a particular unixInodeInfo object.
*/
struct unixFileId {
  dev_t dev;                  /* Device number */
#if OS_VXWORKS
  struct vxworksFileId *pId;  /* Unique file ID for vxworks. */
#else
  /* We are told that some versions of Android contain a bug that
  ** sizes ino_t at only 32-bits instead of 64-bits. (See
  ** https://android-review.googlesource.com/#/c/115351/3/dist/sqlite3.c)
  ** To work around this, always allocate 64-bits for the inode number.  
  ** On small machines that only have 32-bit inodes, this wastes 4 bytes,
  ** but that should not be a big deal. */
  /* WAS:  ino_t ino;   */
  u64 ino;                   /* Inode number */
#endif
};

/*
** An instance of the following structure is allocated for each open
** inode.  Or, on LinuxThreads, there is one of these structures for
** each inode opened by each thread.

#endif

  memset(&fileId, 0, sizeof(fileId));
  fileId.dev = statbuf.st_dev;
#if OS_VXWORKS
  fileId.pId = pFile->pId;
#else
  fileId.ino = (u64)statbuf.st_ino;
#endif
  pInode = inodeList;
  while( pInode && memcmp(&fileId, &pInode->fileId, sizeof(fileId)) ){
    pInode = pInode->pNext;
  }
  if( pInode==0 ){
    pInode = sqlite3_malloc64( sizeof(*pInode) );

*/
static int fileHasMoved(unixFile *pFile){
#if OS_VXWORKS
  return pFile->pInode!=0 && pFile->pId!=pFile->pInode->fileId.pId;
#else
  struct stat buf;
  return pFile->pInode!=0 &&
      (osStat(pFile->zPath, &buf)!=0 
         || (u64)buf.st_ino!=pFile->pInode->fileId.ino);
#endif
}


/*
** Check a unixFile that is a database.  Verify the following:
**

  ** not searching for a reusable file descriptor are not dire.  */
  if( 0==osStat(zPath, &sStat) ){
    unixInodeInfo *pInode;

    unixEnterMutex();
    pInode = inodeList;
    while( pInode && (pInode->fileId.dev!=sStat.st_dev
                     || pInode->fileId.ino!=(u64)sStat.st_ino) ){
       pInode = pInode->pNext;
    }
    if( pInode ){
      UnixUnusedFd **pp;
      for(pp=&pInode->pUnused; *pp && (*pp)->flags!=flags; pp=&((*pp)->pNext));
      pUnused = *pp;
      if( pUnused ){

** Return the value of the iSize parameter specified when Bitvec *p
** was created.
*/
SQLITE_PRIVATE u32 sqlite3BitvecSize(Bitvec *p){
  return p->iSize;
}

#ifndef SQLITE_UNTESTABLE
/*
** Let V[] be an array of unsigned characters sufficient to hold
** up to N bits.  Let I be an integer between 0 and N.  0<=I<N.
** Then the following macros can be used to set, clear, or test
** individual bits within V.
*/
#define SETBIT(V,I)      V[I>>3] |= (1<<(I&7))

  /* Free allocated structure */
bitvec_end:
  sqlite3_free(pTmpSpace);
  sqlite3_free(pV);
  sqlite3BitvecDestroy(pBitvec);
  return rc;
}
#endif /* SQLITE_UNTESTABLE */

/************** End of bitvec.c **********************************************/
/************** Begin file pcache.c ******************************************/
/*
** 2008 August 05
**
** The author disclaims copyright to this source code.  In place of

**
**          assert( sqlite3PcachePageSanity(pPg) );
*/
#if SQLITE_DEBUG
SQLITE_PRIVATE int sqlite3PcachePageSanity(PgHdr *pPg){
  PCache *pCache;
  assert( pPg!=0 );
  assert( pPg->pgno>0 || pPg->pPager==0 );    /* Page number is 1 or more */
  pCache = pPg->pCache;
  assert( pCache!=0 );      /* Every page has an associated PCache */
  if( pPg->flags & PGHDR_CLEAN ){
    assert( (pPg->flags & PGHDR_DIRTY)==0 );/* Cannot be both CLEAN and DIRTY */
    assert( pCache->pDirty!=pPg );          /* CLEAN pages not on dirty list */
    assert( pCache->pDirtyTail!=pPg );
  }

SQLITE_PRIVATE int sqlite3PcacheSize(void){ return sizeof(PCache); }

/*
** Create a new PCache object. Storage space to hold the object
** has already been allocated and is passed in as the p pointer. 
** The caller discovers how much space needs to be allocated by 
** calling sqlite3PcacheSize().
**
** szExtra is some extra space allocated for each page.  The first
** 8 bytes of the extra space will be zeroed as the page is allocated,
** but remaining content will be uninitialized.  Though it is opaque
** to this module, the extra space really ends up being the MemPage
** structure in the pager.
*/
SQLITE_PRIVATE int sqlite3PcacheOpen(
  int szPage,                  /* Size of every page */
  int szExtra,                 /* Extra space associated with each page */
  int bPurgeable,              /* True if pages are on backing store */
  int (*xStress)(void*,PgHdr*),/* Call to try to make pages clean */
  void *pStress,               /* Argument to xStress */
  PCache *p                    /* Preallocated space for the PCache */
){
  memset(p, 0, sizeof(PCache));
  p->szPage = 1;
  p->szExtra = szExtra;
  assert( szExtra>=8 );  /* First 8 bytes will be zeroed */
  p->bPurgeable = bPurgeable;
  p->eCreate = 2;
  p->xStress = xStress;
  p->pStress = pStress;
  p->szCache = 100;
  p->szSpill = 1;
  pcacheTrace(("%p.OPEN szPage %d bPurgeable %d\n",p,szPage,bPurgeable));

){
  int eCreate;
  sqlite3_pcache_page *pRes;

  assert( pCache!=0 );
  assert( pCache->pCache!=0 );
  assert( createFlag==3 || createFlag==0 );

  assert( pCache->eCreate==((pCache->bPurgeable && pCache->pDirty) ? 1 : 2) );

  /* eCreate defines what to do if the page does not exist.
  **    0     Do not allocate a new page.  (createFlag==0)
  **    1     Allocate a new page if doing so is inexpensive.
  **          (createFlag==1 AND bPurgeable AND pDirty)
  **    2     Allocate a new page even it doing so is difficult.

  assert( pPage!=0 );
  pPgHdr = (PgHdr*)pPage->pExtra;
  assert( pPgHdr->pPage==0 );
  memset(&pPgHdr->pDirty, 0, sizeof(PgHdr) - offsetof(PgHdr,pDirty));
  pPgHdr->pPage = pPage;
  pPgHdr->pData = pPage->pBuf;
  pPgHdr->pExtra = (void *)&pPgHdr[1];
  memset(pPgHdr->pExtra, 0, 8);
  pPgHdr->pCache = pCache;
  pPgHdr->pgno = pgno;
  pPgHdr->flags = PGHDR_CLEAN;
  return sqlite3PcacheFetchFinish(pCache,pgno,pPage);
}

/*

*/
#define WAL_SYNC_TRANSACTIONS  0x20   /* Sync at the end of each transaction */
#define SQLITE_SYNC_MASK       0x13   /* Mask off the SQLITE_SYNC_* values */

#ifdef SQLITE_OMIT_WAL
# define sqlite3WalOpen(x,y,z)                   0
# define sqlite3WalLimit(x,y)
# define sqlite3WalClose(v,w,x,y,z)              0
# define sqlite3WalBeginReadTransaction(y,z)     0
# define sqlite3WalEndReadTransaction(z)
# define sqlite3WalDbsize(y)                     0
# define sqlite3WalBeginWriteTransaction(y)      0
# define sqlite3WalEndWriteTransaction(x)        0
# define sqlite3WalUndo(x,y,z)                   0
# define sqlite3WalSavepoint(y,z)
# define sqlite3WalSavepointUndo(y,z)            0
# define sqlite3WalFrames(u,v,w,x,y,z)           0
# define sqlite3WalCheckpoint(q,r,s,t,u,v,w,x,y,z) 0
# define sqlite3WalCallback(z)                   0
# define sqlite3WalExclusiveMode(y,z)            0
# define sqlite3WalHeapMemory(z)                 0
# define sqlite3WalFramesize(z)                  0
# define sqlite3WalFindFrame(x,y,z)              0
# define sqlite3WalFile(x)                       0
#else

#define WAL_SAVEPOINT_NDATA 4

/* Connection to a write-ahead log (WAL) file. 
** There is one object of this type for each pager. 
*/
typedef struct Wal Wal;

/* Open and close a connection to a write-ahead log. */
SQLITE_PRIVATE int sqlite3WalOpen(sqlite3_vfs*, sqlite3_file*, const char *, int, i64, Wal**);
SQLITE_PRIVATE int sqlite3WalClose(Wal *pWal, sqlite3*, int sync_flags, int, u8 *);

/* Set the limiting size of a WAL file. */
SQLITE_PRIVATE void sqlite3WalLimit(Wal*, i64);

/* Used by readers to open (lock) and close (unlock) a snapshot.  A 
** snapshot is like a read-transaction.  It is the state of the database
** at an instant in time.  sqlite3WalOpenSnapshot gets a read lock and

/* Write a frame or frames to the log. */
SQLITE_PRIVATE int sqlite3WalFrames(Wal *pWal, int, PgHdr *, Pgno, int, int);

/* Copy pages from the log to the database file */ 
SQLITE_PRIVATE int sqlite3WalCheckpoint(
  Wal *pWal,                      /* Write-ahead log connection */
  sqlite3 *db,                    /* Check this handle's interrupt flag */
  int eMode,                      /* One of PASSIVE, FULL and RESTART */
  int (*xBusy)(void*),            /* Function to call when busy */
  void *pBusyArg,                 /* Context argument for xBusyHandler */
  int sync_flags,                 /* Flags to sync db file with (or 0) */
  int nBuf,                       /* Size of buffer nBuf */
  u8 *zBuf,                       /* Temporary buffer to use */
  int *pnLog,                     /* OUT: Number of frames in WAL */

** WAL module is using shared-memory, return false. 
*/
SQLITE_PRIVATE int sqlite3WalHeapMemory(Wal *pWal);

#ifdef SQLITE_ENABLE_SNAPSHOT
SQLITE_PRIVATE int sqlite3WalSnapshotGet(Wal *pWal, sqlite3_snapshot **ppSnapshot);
SQLITE_PRIVATE void sqlite3WalSnapshotOpen(Wal *pWal, sqlite3_snapshot *pSnapshot);
SQLITE_PRIVATE int sqlite3WalSnapshotRecover(Wal *pWal);
#endif

#ifdef SQLITE_ENABLE_ZIPVFS
/* If the WAL file is not empty, return the number of bytes of content
** stored in each frame (i.e. the db page-size when the WAL was created).
*/
SQLITE_PRIVATE int sqlite3WalFramesize(Wal *pWal);

  int (*xBusyHandler)(void*); /* Function to call when busy */
  void *pBusyHandlerArg;      /* Context argument for xBusyHandler */
  int aStat[3];               /* Total cache hits, misses and writes */
#ifdef SQLITE_TEST
  int nRead;                  /* Database pages read */
#endif
  void (*xReiniter)(DbPage*); /* Call this routine when reloading pages */
  int (*xGet)(Pager*,Pgno,DbPage**,int); /* Routine to fetch a patch */
#ifdef SQLITE_HAS_CODEC
  void *(*xCodec)(void*,void*,Pgno,int); /* Routine for en/decoding data */
  void (*xCodecSizeChng)(void*,int,int); /* Notify of page size changes */
  void (*xCodecFree)(void*);             /* Destructor for the codec */
  void *pCodec;               /* First argument to xCodec... methods */
#endif
  char *pTmpSpace;            /* Pager.pageSize bytes of space for tmp use */

      , p->journalOff, p->journalHdr
      , (int)p->dbSize, (int)p->dbOrigSize, (int)p->dbFileSize
  );

  return zRet;
}
#endif

/* Forward references to the various page getters */
static int getPageNormal(Pager*,Pgno,DbPage**,int);
static int getPageError(Pager*,Pgno,DbPage**,int);
#if SQLITE_MAX_MMAP_SIZE>0
static int getPageMMap(Pager*,Pgno,DbPage**,int);
#endif

/*
** Set the Pager.xGet method for the appropriate routine used to fetch
** content from the pager.
*/
static void setGetterMethod(Pager *pPager){
  if( pPager->errCode ){
    pPager->xGet = getPageError;
#if SQLITE_MAX_MMAP_SIZE>0
  }else if( USEFETCH(pPager)
#ifdef SQLITE_HAS_CODEC
   && pPager->xCodec==0
#endif
  ){
    pPager->xGet = getPageMMap;
#endif /* SQLITE_MAX_MMAP_SIZE>0 */
  }else{
    pPager->xGet = getPageNormal;
  }
}

/*
** Return true if it is necessary to write page *pPg into the sub-journal.
** A page needs to be written into the sub-journal if there exists one
** or more open savepoints for which:
**
**   * The page-number is less than or equal to PagerSavepoint.nOrig, and

      pPager->changeCountDone = 0;
      pPager->eState = PAGER_OPEN;
    }else{
      pPager->eState = (isOpen(pPager->jfd) ? PAGER_OPEN : PAGER_READER);
    }
    if( USEFETCH(pPager) ) sqlite3OsUnfetch(pPager->fd, 0, 0);
    pPager->errCode = SQLITE_OK;
    setGetterMethod(pPager);
  }

  pPager->journalOff = 0;
  pPager->journalHdr = 0;
  pPager->setMaster = 0;
}

       pPager->errCode==SQLITE_FULL ||
       pPager->errCode==SQLITE_OK ||
       (pPager->errCode & 0xff)==SQLITE_IOERR
  );
  if( rc2==SQLITE_FULL || rc2==SQLITE_IOERR ){
    pPager->errCode = rc;
    pPager->eState = PAGER_ERROR;
    setGetterMethod(pPager);
  }
  return rc;
}

static int pager_truncate(Pager *pPager, Pgno nPage);

/*

  }
#endif

  sqlite3BitvecDestroy(pPager->pInJournal);
  pPager->pInJournal = 0;
  pPager->nRec = 0;
  if( rc==SQLITE_OK ){
    if( MEMDB || pagerFlushOnCommit(pPager, bCommit) ){
      sqlite3PcacheCleanAll(pPager->pPCache);
    }else{
      sqlite3PcacheClearWritable(pPager->pPCache);
    }
    sqlite3PcacheTruncate(pPager->pPCache, pPager->dbSize);
  }

static void pagerFixMaplimit(Pager *pPager){
#if SQLITE_MAX_MMAP_SIZE>0
  sqlite3_file *fd = pPager->fd;
  if( isOpen(fd) && fd->pMethods->iVersion>=3 ){
    sqlite3_int64 sz;
    sz = pPager->szMmap;
    pPager->bUseFetch = (sz>0);
    setGetterMethod(pPager);
    sqlite3OsFileControlHint(pPager->fd, SQLITE_FCNTL_MMAP_SIZE, &sz);
  }
#endif
}

/*
** Change the maximum size of any memory mapping made of the database file.

  }
  if( rc==SQLITE_OK ){
    rc = sqlite3OsFileSize(pPager->jfd, &pPager->journalHdr);
  }
  return rc;
}

#if SQLITE_MAX_MMAP_SIZE>0
/*
** Obtain a reference to a memory mapped page object for page number pgno. 
** The new object will use the pointer pData, obtained from xFetch().
** If successful, set *ppPage to point to the new page reference
** and return SQLITE_OK. Otherwise, return an SQLite error code and set
** *ppPage to zero.
**

){
  PgHdr *p;                       /* Memory mapped page to return */
  
  if( pPager->pMmapFreelist ){
    *ppPage = p = pPager->pMmapFreelist;
    pPager->pMmapFreelist = p->pDirty;
    p->pDirty = 0;
    assert( pPager->nExtra>=8 );
    memset(p->pExtra, 0, 8);
  }else{
    *ppPage = p = (PgHdr *)sqlite3MallocZero(sizeof(PgHdr) + pPager->nExtra);
    if( p==0 ){
      sqlite3OsUnfetch(pPager->fd, (i64)(pgno-1) * pPager->pageSize, pData);
      return SQLITE_NOMEM_BKPT;
    }
    p->pExtra = (void *)&p[1];

  p->pgno = pgno;
  p->pData = pData;
  pPager->nMmapOut++;

  return SQLITE_OK;
}
#endif

/*
** Release a reference to page pPg. pPg must have been returned by an 
** earlier call to pagerAcquireMapPage().
*/
static void pagerReleaseMapPage(PgHdr *pPg){
  Pager *pPager = pPg->pPager;

** result in a coredump.
**
** This function always succeeds. If a transaction is active an attempt
** is made to roll it back. If an error occurs during the rollback 
** a hot journal may be left in the filesystem but no error is returned
** to the caller.
*/
SQLITE_PRIVATE int sqlite3PagerClose(Pager *pPager, sqlite3 *db){
  u8 *pTmp = (u8 *)pPager->pTmpSpace;

  assert( db || pagerUseWal(pPager)==0 );
  assert( assert_pager_state(pPager) );
  disable_simulated_io_errors();
  sqlite3BeginBenignMalloc();
  pagerFreeMapHdrs(pPager);
  /* pPager->errCode = 0; */
  pPager->exclusiveMode = 0;
#ifndef SQLITE_OMIT_WAL
  assert( db || pPager->pWal==0 );
  sqlite3WalClose(pPager->pWal, db, pPager->ckptSyncFlags, pPager->pageSize,
      (db && (db->flags & SQLITE_NoCkptOnClose) ? 0 : pTmp)
  );
  pPager->pWal = 0;
#endif
  pager_reset(pPager);
  if( MEMDB ){
    pager_unlock(pPager);
  }else{
    /* If it is open, sync the journal file before calling UnlockAndRollback.

** and used as the file to be cached. Temporary files are be deleted
** automatically when they are closed. If zFilename is ":memory:" then 
** all information is held in cache. It is never written to disk. 
** This can be used to implement an in-memory database.
**
** The nExtra parameter specifies the number of bytes of space allocated
** along with each page reference. This space is available to the user
** via the sqlite3PagerGetExtra() API.  When a new page is allocated, the
** first 8 bytes of this space are zeroed but the remainder is uninitialized.
** (The extra space is used by btree as the MemPage object.)
**
** The flags argument is used to specify properties that affect the
** operation of the pager. It should be passed some bitwise combination
** of the PAGER_* flags.
**
** The vfsFlags parameter is a bitmask to pass to the flags parameter
** of the xOpen() method of the supplied VFS when opening files. 

    assert( pPager->memDb==0 );
    rc = sqlite3PagerSetPagesize(pPager, &szPageDflt, -1);
    testcase( rc!=SQLITE_OK );
  }

  /* Initialize the PCache object. */
  if( rc==SQLITE_OK ){

    nExtra = ROUND8(nExtra);
    assert( nExtra>=8 && nExtra<1000 );
    rc = sqlite3PcacheOpen(szPageDflt, nExtra, !memDb,
                       !memDb?pagerStress:0, (void *)pPager, pPager->pPCache);
  }

  /* If an error occurred above, free the  Pager structure and close the file.
  */
  if( rc!=SQLITE_OK ){

    pPager->journalMode = PAGER_JOURNALMODE_OFF;
  }else if( memDb ){
    pPager->journalMode = PAGER_JOURNALMODE_MEMORY;
  }
  /* pPager->xBusyHandler = 0; */
  /* pPager->pBusyHandlerArg = 0; */
  pPager->xReiniter = xReinit;
  setGetterMethod(pPager);
  /* memset(pPager->aHash, 0, sizeof(pPager->aHash)); */
  /* pPager->szMmap = SQLITE_DEFAULT_MMAP_SIZE // will be set by btree.c */

  *ppPager = pPager;
  return SQLITE_OK;
}

static void pagerUnlockIfUnused(Pager *pPager){
  if( pPager->nMmapOut==0 && (sqlite3PcacheRefCount(pPager->pPCache)==0) ){
    pagerUnlockAndRollback(pPager);
  }
}

/*
** The page getter methods each try to acquire a reference to a
** page with page number pgno. If the requested reference is 
** successfully obtained, it is copied to *ppPage and SQLITE_OK returned.
**
** There are different implementations of the getter method depending
** on the current state of the pager.
**
**     getPageNormal()         --  The normal getter
**     getPageError()          --  Used if the pager is in an error state
**     getPageMmap()           --  Used if memory-mapped I/O is enabled
**
** If the requested page is already in the cache, it is returned. 
** Otherwise, a new page object is allocated and populated with data
** read from the database file. In some cases, the pcache module may
** choose not to allocate a new page object and may reuse an existing
** object with no outstanding references.
**
** The extra data appended to a page is always initialized to zeros the 
** first time a page is loaded into memory. If the page requested is 
** already in the cache when this function is called, then the extra
** data is left as it was when the page object was last used.
**
** If the database image is smaller than the requested page or if 
** the flags parameter contains the PAGER_GET_NOCONTENT bit and the 
** requested page is not already stored in the cache, then no 
** actual disk read occurs. In this case the memory image of the 
** page is initialized to all zeros. 
**
** If PAGER_GET_NOCONTENT is true, it means that we do not care about
** the contents of the page. This occurs in two scenarios:
**
**   a) When reading a free-list leaf page from the database, and
**
**   b) When a savepoint is being rolled back and we need to load
**      a new page into the cache to be filled with the data read
**      from the savepoint journal.
**
** If PAGER_GET_NOCONTENT is true, then the data returned is zeroed instead
** of being read from the database. Additionally, the bits corresponding
** to pgno in Pager.pInJournal (bitvec of pages already written to the
** journal file) and the PagerSavepoint.pInSavepoint bitvecs of any open
** savepoints are set. This means if the page is made writable at any
** point in the future, using a call to sqlite3PagerWrite(), its contents
** will not be journaled. This saves IO.
**
** The acquisition might fail for several reasons.  In all cases,
** an appropriate error code is returned and *ppPage is set to NULL.
**
** See also sqlite3PagerLookup().  Both this routine and Lookup() attempt
** to find a page in the in-memory cache first.  If the page is not already
** in memory, this routine goes to disk to read it in whereas Lookup()
** just returns 0.  This routine acquires a read-lock the first time it
** has to go to disk, and could also playback an old journal if necessary.
** Since Lookup() never goes to disk, it never has to deal with locks
** or journal files.
*/
static int getPageNormal(
  Pager *pPager,      /* The pager open on the database file */
  Pgno pgno,          /* Page number to fetch */
  DbPage **ppPage,    /* Write a pointer to the page here */
  int flags           /* PAGER_GET_XXX flags */
){
  int rc = SQLITE_OK;
  PgHdr *pPg;

  u8 noContent;                   /* True if PAGER_GET_NOCONTENT is set */
  sqlite3_pcache_page *pBase;
















  assert( pPager->errCode==SQLITE_OK );

  assert( pPager->eState>=PAGER_READER );
  assert( assert_pager_state(pPager) );


  assert( pPager->hasHeldSharedLock==1 );






























  if( pgno==0 ) return SQLITE_CORRUPT_BKPT;









  pBase = sqlite3PcacheFetch(pPager->pPCache, pgno, 3);
  if( pBase==0 ){

















    pPg = 0;
    rc = sqlite3PcacheFetchStress(pPager->pPCache, pgno, &pBase);
    if( rc!=SQLITE_OK ) goto pager_acquire_err;
    if( pBase==0 ){
      rc = SQLITE_NOMEM_BKPT;
      goto pager_acquire_err;
    }
  }
  pPg = *ppPage = sqlite3PcacheFetchFinish(pPager->pPCache, pgno, pBase);
  assert( pPg==(*ppPage) );
  assert( pPg->pgno==pgno );
  assert( pPg->pPager==pPager || pPg->pPager==0 );

  noContent = (flags & PAGER_GET_NOCONTENT)!=0;
  if( pPg->pPager && !noContent ){
    /* In this case the pcache already contains an initialized copy of
    ** the page. Return without further ado.  */
    assert( pgno<=PAGER_MAX_PGNO && pgno!=PAGER_MJ_PGNO(pPager) );
    pPager->aStat[PAGER_STAT_HIT]++;
    return SQLITE_OK;

  }else{
    /* The pager cache has created a new page. Its content needs to 
    ** be initialized. But first some error checks:
    **


    ** (1) The maximum page number is 2^31
    ** (2) Never try to fetch the locking page
    */
    if( pgno>PAGER_MAX_PGNO || pgno==PAGER_MJ_PGNO(pPager) ){
      rc = SQLITE_CORRUPT_BKPT;
      goto pager_acquire_err;
    }

    pPg->pPager = pPager;

    assert( !isOpen(pPager->fd) || !MEMDB );
    if( !isOpen(pPager->fd) || pPager->dbSize<pgno || noContent ){
      if( pgno>pPager->mxPgno ){
        rc = SQLITE_FULL;
        goto pager_acquire_err;
      }

        TESTONLY( rc = ) addToSavepointBitvecs(pPager, pgno);
        testcase( rc==SQLITE_NOMEM );
        sqlite3EndBenignMalloc();
      }
      memset(pPg->pData, 0, pPager->pageSize);
      IOTRACE(("ZERO %p %d\n", pPager, pgno));
    }else{
      u32 iFrame = 0;                 /* Frame to read from WAL file */
      if( pagerUseWal(pPager) ){
        rc = sqlite3WalFindFrame(pPager->pWal, pgno, &iFrame);
        if( rc!=SQLITE_OK ) goto pager_acquire_err;
      }
      assert( pPg->pPager==pPager );
      pPager->aStat[PAGER_STAT_MISS]++;
      rc = readDbPage(pPg, iFrame);
      if( rc!=SQLITE_OK ){
        goto pager_acquire_err;
      }
    }
    pager_set_pagehash(pPg);
  }

  return SQLITE_OK;

pager_acquire_err:
  assert( rc!=SQLITE_OK );
  if( pPg ){
    sqlite3PcacheDrop(pPg);
  }
  pagerUnlockIfUnused(pPager);
  *ppPage = 0;
  return rc;
}

#if SQLITE_MAX_MMAP_SIZE>0
/* The page getter for when memory-mapped I/O is enabled */
static int getPageMMap(
  Pager *pPager,      /* The pager open on the database file */
  Pgno pgno,          /* Page number to fetch */
  DbPage **ppPage,    /* Write a pointer to the page here */
  int flags           /* PAGER_GET_XXX flags */
){
  int rc = SQLITE_OK;
  PgHdr *pPg = 0;
  u32 iFrame = 0;                 /* Frame to read from WAL file */

  /* It is acceptable to use a read-only (mmap) page for any page except
  ** page 1 if there is no write-transaction open or the ACQUIRE_READONLY
  ** flag was specified by the caller. And so long as the db is not a 
  ** temporary or in-memory database.  */
  const int bMmapOk = (pgno>1
   && (pPager->eState==PAGER_READER || (flags & PAGER_GET_READONLY))
  );

  assert( USEFETCH(pPager) );
#ifdef SQLITE_HAS_CODEC
  assert( pPager->xCodec==0 );
#endif

  /* Optimization note:  Adding the "pgno<=1" term before "pgno==0" here
  ** allows the compiler optimizer to reuse the results of the "pgno>1"
  ** test in the previous statement, and avoid testing pgno==0 in the
  ** common case where pgno is large. */
  if( pgno<=1 && pgno==0 ){
    return SQLITE_CORRUPT_BKPT;
  }
  assert( pPager->eState>=PAGER_READER );
  assert( assert_pager_state(pPager) );
  assert( pPager->hasHeldSharedLock==1 );
  assert( pPager->errCode==SQLITE_OK );

  if( bMmapOk && pagerUseWal(pPager) ){
    rc = sqlite3WalFindFrame(pPager->pWal, pgno, &iFrame);
    if( rc!=SQLITE_OK ){
      *ppPage = 0;
      return rc;
    }
  }
  if( bMmapOk && iFrame==0 ){
    void *pData = 0;
    rc = sqlite3OsFetch(pPager->fd, 
        (i64)(pgno-1) * pPager->pageSize, pPager->pageSize, &pData
    );
    if( rc==SQLITE_OK && pData ){
      if( pPager->eState>PAGER_READER || pPager->tempFile ){
        pPg = sqlite3PagerLookup(pPager, pgno);
      }
      if( pPg==0 ){
        rc = pagerAcquireMapPage(pPager, pgno, pData, &pPg);
     }else{
        sqlite3OsUnfetch(pPager->fd, (i64)(pgno-1)*pPager->pageSize, pData);
      }
      if( pPg ){
        assert( rc==SQLITE_OK );
        *ppPage = pPg;
        return SQLITE_OK;
      }
    }
    if( rc!=SQLITE_OK ){
      *ppPage = 0;
      return rc;
    }
  }
  return getPageNormal(pPager, pgno, ppPage, flags);
}
#endif /* SQLITE_MAX_MMAP_SIZE>0 */

/* The page getter method for when the pager is an error state */
static int getPageError(
  Pager *pPager,      /* The pager open on the database file */
  Pgno pgno,          /* Page number to fetch */
  DbPage **ppPage,    /* Write a pointer to the page here */
  int flags           /* PAGER_GET_XXX flags */
){
  UNUSED_PARAMETER(pgno);
  UNUSED_PARAMETER(flags);
  assert( pPager->errCode!=SQLITE_OK );
  *ppPage = 0;
  return pPager->errCode;
}


/* Dispatch all page fetch requests to the appropriate getter method.
*/
SQLITE_PRIVATE int sqlite3PagerGet(
  Pager *pPager,      /* The pager open on the database file */
  Pgno pgno,          /* Page number to fetch */
  DbPage **ppPage,    /* Write a pointer to the page here */
  int flags           /* PAGER_GET_XXX flags */
){
  return pPager->xGet(pPager, pgno, ppPage, flags);
}

/*
** Acquire a page if it is already in the in-memory cache.  Do
** not read the page from disk.  Return a pointer to the page,
** or 0 if the page is not in cache. 
**

** as appropriate. Otherwise, SQLITE_OK.
*/
SQLITE_PRIVATE int sqlite3PagerWrite(PgHdr *pPg){
  Pager *pPager = pPg->pPager;
  assert( (pPg->flags & PGHDR_MMAP)==0 );
  assert( pPager->eState>=PAGER_WRITER_LOCKED );
  assert( assert_pager_state(pPager) );


  if( (pPg->flags & PGHDR_WRITEABLE)!=0 && pPager->dbSize>=pPg->pgno ){
    if( pPager->nSavepoint ) return subjournalPageIfRequired(pPg);
    return SQLITE_OK;
  }else if( pPager->errCode ){
    return pPager->errCode;
  }else if( pPager->sectorSize > (u32)pPager->pageSize ){
    assert( pPager->tempFile==0 );
    return pagerWriteLargeSector(pPg);
  }else{
    return pager_write(pPg);
  }
}

    if( !MEMDB && eState>PAGER_WRITER_LOCKED ){
      /* This can happen using journal_mode=off. Move the pager to the error 
      ** state to indicate that the contents of the cache may not be trusted.
      ** Any active readers will get SQLITE_ABORT.
      */
      pPager->errCode = SQLITE_ABORT;
      pPager->eState = PAGER_ERROR;
      setGetterMethod(pPager);
      return rc;
    }
  }else{
    rc = pager_playback(pPager, 0);
  }

  assert( pPager->eState==PAGER_READER || rc!=SQLITE_OK );

    ** can be rolled back at the ZipVFS level.  */
    else if( 
        pPager->journalMode==PAGER_JOURNALMODE_OFF 
     && pPager->eState>=PAGER_WRITER_CACHEMOD
    ){
      pPager->errCode = SQLITE_ABORT;
      pPager->eState = PAGER_ERROR;
      setGetterMethod(pPager);
    }
#endif
  }

  return rc;
}

  void *pCodec
){
  if( pPager->xCodecFree ) pPager->xCodecFree(pPager->pCodec);
  pPager->xCodec = pPager->memDb ? 0 : xCodec;
  pPager->xCodecSizeChng = xCodecSizeChng;
  pPager->xCodecFree = xCodecFree;
  pPager->pCodec = pCodec;
  setGetterMethod(pPager);
  pagerReportSize(pPager);
}
SQLITE_PRIVATE void *sqlite3PagerGetCodec(Pager *pPager){
  return pPager->pCodec;
}

/*

/*
** This function is called when the user invokes "PRAGMA wal_checkpoint",
** "PRAGMA wal_blocking_checkpoint" or calls the sqlite3_wal_checkpoint()
** or wal_blocking_checkpoint() API functions.
**
** Parameter eMode is one of SQLITE_CHECKPOINT_PASSIVE, FULL or RESTART.
*/
SQLITE_PRIVATE int sqlite3PagerCheckpoint(
  Pager *pPager,                  /* Checkpoint on this pager */
  sqlite3 *db,                    /* Db handle used to check for interrupts */
  int eMode,                      /* Type of checkpoint */
  int *pnLog,                     /* OUT: Final number of frames in log */
  int *pnCkpt                     /* OUT: Final number of checkpointed frames */
){
  int rc = SQLITE_OK;
  if( pPager->pWal ){
    rc = sqlite3WalCheckpoint(pPager->pWal, db, eMode,
        (eMode==SQLITE_CHECKPOINT_PASSIVE ? 0 : pPager->xBusyHandler),
        pPager->pBusyHandlerArg,
        pPager->ckptSyncFlags, pPager->pageSize, (u8 *)pPager->pTmpSpace,
        pnLog, pnCkpt
    );
  }
  return rc;

** to switching from WAL to rollback mode.
**
** Before closing the log file, this function attempts to take an 
** EXCLUSIVE lock on the database file. If this cannot be obtained, an
** error (SQLITE_BUSY) is returned and the log connection is not closed.
** If successful, the EXCLUSIVE lock is not released before returning.
*/
SQLITE_PRIVATE int sqlite3PagerCloseWal(Pager *pPager, sqlite3 *db){
  int rc = SQLITE_OK;

  assert( pPager->journalMode==PAGER_JOURNALMODE_WAL );

  /* If the log file is not already open, but does exist in the file-system,
  ** it may need to be checkpointed before the connection can switch to
  ** rollback mode. Open it now so this can happen.

    
  /* Checkpoint and close the log. Because an EXCLUSIVE lock is held on
  ** the database file, the log and log-summary files will be deleted.
  */
  if( rc==SQLITE_OK && pPager->pWal ){
    rc = pagerExclusiveLock(pPager);
    if( rc==SQLITE_OK ){
      rc = sqlite3WalClose(pPager->pWal, db, pPager->ckptSyncFlags,
                           pPager->pageSize, (u8*)pPager->pTmpSpace);
      pPager->pWal = 0;
      pagerFixMaplimit(pPager);
      if( rc && !pPager->exclusiveMode ) pagerUnlockDb(pPager, SHARED_LOCK);
    }
  }
  return rc;

  if( pPager->pWal ){
    sqlite3WalSnapshotOpen(pPager->pWal, pSnapshot);
  }else{
    rc = SQLITE_ERROR;
  }
  return rc;
}

/*
** If this is a WAL database, call sqlite3WalSnapshotRecover(). If this 
** is not a WAL database, return an error.
*/
SQLITE_PRIVATE int sqlite3PagerSnapshotRecover(Pager *pPager){
  int rc;
  if( pPager->pWal ){
    rc = sqlite3WalSnapshotRecover(pPager->pWal);
  }else{
    rc = SQLITE_ERROR;
  }
  return rc;
}
#endif /* SQLITE_ENABLE_SNAPSHOT */
#endif /* !SQLITE_OMIT_WAL */

#ifdef SQLITE_ENABLE_ZIPVFS
/*
** A read-lock must be held on the pager when this function is called. If
** the pager is in WAL mode and the WAL file currently contains one or more

**
** The caller must be holding sufficient locks to ensure that no other
** checkpoint is running (in any other thread or process) at the same
** time.
*/
static int walCheckpoint(
  Wal *pWal,                      /* Wal connection */
  sqlite3 *db,                    /* Check for interrupts on this handle */
  int eMode,                      /* One of PASSIVE, FULL or RESTART */
  int (*xBusy)(void*),            /* Function to call when busy */
  void *pBusyArg,                 /* Context argument for xBusyHandler */
  int sync_flags,                 /* Flags for OsSync() (or 0) */
  u8 *zBuf                        /* Temporary buffer to use */
){
  int rc = SQLITE_OK;             /* Return code */

      }


      /* Iterate through the contents of the WAL, copying data to the db file */
      while( rc==SQLITE_OK && 0==walIteratorNext(pIter, &iDbpage, &iFrame) ){
        i64 iOffset;
        assert( walFramePgno(pWal, iFrame)==iDbpage );
        if( db->u1.isInterrupted ){
          rc = db->mallocFailed ? SQLITE_NOMEM_BKPT : SQLITE_INTERRUPT;
          break;
        }
        if( iFrame<=nBackfill || iFrame>mxSafeFrame || iDbpage>mxPage ){
          continue;
        }
        iOffset = walFrameOffset(iFrame, szPage) + WAL_FRAME_HDRSIZE;
        /* testcase( IS_BIG_INT(iOffset) ); // requires a 4GiB WAL file */
        rc = sqlite3OsRead(pWal->pWalFd, zBuf, szPage, iOffset);
        if( rc!=SQLITE_OK ) break;

}

/*
** Close a connection to a log file.
*/
SQLITE_PRIVATE int sqlite3WalClose(
  Wal *pWal,                      /* Wal to close */
  sqlite3 *db,                    /* For interrupt flag */
  int sync_flags,                 /* Flags to pass to OsSync() (or 0) */
  int nBuf,
  u8 *zBuf                        /* Buffer of at least nBuf bytes */
){
  int rc = SQLITE_OK;
  if( pWal ){
    int isDelete = 0;             /* True to unlink wal and wal-index files */

    /* If an EXCLUSIVE lock can be obtained on the database file (using the
    ** ordinary, rollback-mode locking methods, this guarantees that the
    ** connection associated with this log file is the only connection to
    ** the database. In this case checkpoint the database and unlink both
    ** the wal and wal-index files.
    **
    ** The EXCLUSIVE lock is not released before returning.
    */
    if( zBuf!=0
     && SQLITE_OK==(rc = sqlite3OsLock(pWal->pDbFd, SQLITE_LOCK_EXCLUSIVE))
    ){
      if( pWal->exclusiveMode==WAL_NORMAL_MODE ){
        pWal->exclusiveMode = WAL_EXCLUSIVE_MODE;
      }
      rc = sqlite3WalCheckpoint(pWal, db, 
          SQLITE_CHECKPOINT_PASSIVE, 0, 0, sync_flags, nBuf, zBuf, 0, 0
      );
      if( rc==SQLITE_OK ){
        int bPersist = -1;
        sqlite3OsFileControlHint(
            pWal->pDbFd, SQLITE_FCNTL_PERSIST_WAL, &bPersist
        );
        if( bPersist!=1 ){

  }else{
    assert( mxReadMark<=pWal->hdr.mxFrame );
    pWal->readLock = (i16)mxI;
  }
  return rc;
}

#ifdef SQLITE_ENABLE_SNAPSHOT
/*
** Attempt to reduce the value of the WalCkptInfo.nBackfillAttempted 
** variable so that older snapshots can be accessed. To do this, loop
** through all wal frames from nBackfillAttempted to (nBackfill+1), 
** comparing their content to the corresponding page with the database
** file, if any. Set nBackfillAttempted to the frame number of the
** first frame for which the wal file content matches the db file.
**
** This is only really safe if the file-system is such that any page 
** writes made by earlier checkpointers were atomic operations, which 
** is not always true. It is also possible that nBackfillAttempted
** may be left set to a value larger than expected, if a wal frame
** contains content that duplicate of an earlier version of the same
** page.
**
** SQLITE_OK is returned if successful, or an SQLite error code if an
** error occurs. It is not an error if nBackfillAttempted cannot be
** decreased at all.
*/
SQLITE_PRIVATE int sqlite3WalSnapshotRecover(Wal *pWal){
  int rc;

  assert( pWal->readLock>=0 );
  rc = walLockExclusive(pWal, WAL_CKPT_LOCK, 1);
  if( rc==SQLITE_OK ){
    volatile WalCkptInfo *pInfo = walCkptInfo(pWal);
    int szPage = (int)pWal->szPage;
    i64 szDb;                   /* Size of db file in bytes */

    rc = sqlite3OsFileSize(pWal->pDbFd, &szDb);
    if( rc==SQLITE_OK ){
      void *pBuf1 = sqlite3_malloc(szPage);
      void *pBuf2 = sqlite3_malloc(szPage);
      if( pBuf1==0 || pBuf2==0 ){
        rc = SQLITE_NOMEM;
      }else{
        u32 i = pInfo->nBackfillAttempted;
        for(i=pInfo->nBackfillAttempted; i>pInfo->nBackfill; i--){
          volatile ht_slot *dummy;
          volatile u32 *aPgno;      /* Array of page numbers */
          u32 iZero;                /* Frame corresponding to aPgno[0] */
          u32 pgno;                 /* Page number in db file */
          i64 iDbOff;               /* Offset of db file entry */
          i64 iWalOff;              /* Offset of wal file entry */

          rc = walHashGet(pWal, walFramePage(i), &dummy, &aPgno, &iZero);
          if( rc!=SQLITE_OK ) break;
          pgno = aPgno[i-iZero];
          iDbOff = (i64)(pgno-1) * szPage;

          if( iDbOff+szPage<=szDb ){
            iWalOff = walFrameOffset(i, szPage) + WAL_FRAME_HDRSIZE;
            rc = sqlite3OsRead(pWal->pWalFd, pBuf1, szPage, iWalOff);

            if( rc==SQLITE_OK ){
              rc = sqlite3OsRead(pWal->pDbFd, pBuf2, szPage, iDbOff);
            }

            if( rc!=SQLITE_OK || 0==memcmp(pBuf1, pBuf2, szPage) ){
              break;
            }
          }

          pInfo->nBackfillAttempted = i-1;
        }
      }

      sqlite3_free(pBuf1);
      sqlite3_free(pBuf2);
    }
    walUnlockExclusive(pWal, WAL_CKPT_LOCK, 1);
  }

  return rc;
}
#endif /* SQLITE_ENABLE_SNAPSHOT */

/*
** Begin a read transaction on the database.
**
** This routine used to be called sqlite3OpenSnapshot() and with good reason:
** it takes a snapshot of the state of the WAL and wal-index for the current
** instant in time.  The current thread will continue to use this snapshot.
** Other threads might append new content to the WAL and wal-index but

      /* It is possible that there is a checkpointer thread running 
      ** concurrent with this code. If this is the case, it may be that the
      ** checkpointer has already determined that it will checkpoint 
      ** snapshot X, where X is later in the wal file than pSnapshot, but 
      ** has not yet set the pInfo->nBackfillAttempted variable to indicate 
      ** its intent. To avoid the race condition this leads to, ensure that
      ** there is no checkpointer process by taking a shared CKPT lock 
      ** before checking pInfo->nBackfillAttempted.  
      **
      ** TODO: Does the aReadMark[] lock prevent a checkpointer from doing
      **       this already?
      */
      rc = walLockShared(pWal, WAL_CKPT_LOCK);

      if( rc==SQLITE_OK ){
        /* Check that the wal file has not been wrapped. Assuming that it has
        ** not, also check that no checkpointer has attempted to checkpoint any
        ** frames beyond pSnapshot->mxFrame. If either of these conditions are
        ** true, return SQLITE_BUSY_SNAPSHOT. Otherwise, overwrite pWal->hdr

** we can from WAL into the database.
**
** If parameter xBusy is not NULL, it is a pointer to a busy-handler
** callback. In this case this function runs a blocking checkpoint.
*/
SQLITE_PRIVATE int sqlite3WalCheckpoint(
  Wal *pWal,                      /* Wal connection */
  sqlite3 *db,                    /* Check this handle's interrupt flag */
  int eMode,                      /* PASSIVE, FULL, RESTART, or TRUNCATE */
  int (*xBusy)(void*),            /* Function to call when busy */
  void *pBusyArg,                 /* Context argument for xBusyHandler */
  int sync_flags,                 /* Flags to sync db file with (or 0) */
  int nBuf,                       /* Size of temporary buffer */
  u8 *zBuf,                       /* Temporary buffer to use */
  int *pnLog,                     /* OUT: Number of frames in WAL */

  /* Copy data from the log to the database file. */
  if( rc==SQLITE_OK ){

    if( pWal->hdr.mxFrame && walPagesize(pWal)!=nBuf ){
      rc = SQLITE_CORRUPT_BKPT;
    }else{
      rc = walCheckpoint(pWal, db, eMode2, xBusy2, pBusyArg, sync_flags, zBuf);
    }

    /* If no error occurred, set the output variables. */
    if( rc==SQLITE_OK || rc==SQLITE_BUSY ){
      if( pnLog ) *pnLog = (int)pWal->hdr.mxFrame;
      if( pnCkpt ) *pnCkpt = (int)(walCkptInfo(pWal)->nBackfill);
    }

/* Create a snapshot object.  The content of a snapshot is opaque to
** every other subsystem, so the WAL module can put whatever it needs
** in the object.
*/
SQLITE_PRIVATE int sqlite3WalSnapshotGet(Wal *pWal, sqlite3_snapshot **ppSnapshot){
  int rc = SQLITE_OK;
  WalIndexHdr *pRet;
  static const u32 aZero[4] = { 0, 0, 0, 0 };

  assert( pWal->readLock>=0 && pWal->writeLock==0 );

  if( memcmp(&pWal->hdr.aFrameCksum[0],aZero,16)==0 ){
    *ppSnapshot = 0;
    return SQLITE_ERROR;
  }
  pRet = (WalIndexHdr*)sqlite3_malloc(sizeof(WalIndexHdr));
  if( pRet==0 ){
    rc = SQLITE_NOMEM_BKPT;
  }else{
    memcpy(pRet, &pWal->hdr, sizeof(WalIndexHdr));
    *ppSnapshot = (sqlite3_snapshot*)pRet;
  }

*/
#define PTF_INTKEY    0x01
#define PTF_ZERODATA  0x02
#define PTF_LEAFDATA  0x04
#define PTF_LEAF      0x08

/*
** An instance of this object stores information about each a single database
** page that has been loaded into memory.  The information in this object
** is derived from the raw on-disk page content.
**
** As each database page is loaded into memory, the pager allocats an
** instance of this object and zeros the first 8 bytes.  (This is the
** "extra" information associated with each page of the pager.)

**
** Access to all fields of this structure is controlled by the mutex
** stored in MemPage.pBt->mutex.
*/
struct MemPage {
  u8 isInit;           /* True if previously initialized. MUST BE FIRST! */
  u8 bBusy;            /* Prevent endless loops on corrupt database files */
  u8 intKey;           /* True if table b-trees.  False for index b-trees */
  u8 intKeyLeaf;       /* True if the leaf of an intKey table */
  Pgno pgno;           /* Page number for this page */
  /* Only the first 8 bytes (above) are zeroed by pager.c when a new page
  ** is allocated. All fields that follow must be initialized before use */
  u8 leaf;             /* True if a leaf page */
  u8 hdrOffset;        /* 100 for page 1.  0 otherwise */
  u8 childPtrSize;     /* 0 if leaf==1.  4 if leaf==0 */
  u8 max1bytePayload;  /* min(maxLocal,127) */
  u8 nOverflow;        /* Number of overflow cell bodies in aCell[] */
  u16 maxLocal;        /* Copy of BtShared.maxLocal or BtShared.maxLeaf */
  u16 minLocal;        /* Copy of BtShared.minLocal or BtShared.minLeaf */
  u16 cellOffset;      /* Index in aData of first cell pointer */
  u16 nFree;           /* Number of free bytes on the page */
  u16 nCell;           /* Number of cells on this page, local and ovfl */
  u16 maskPage;        /* Mask for page offset */
  u16 aiOvfl[4];       /* Insert the i-th overflow cell before the aiOvfl-th
                       ** non-overflow cell */
  u8 *apOvfl[4];       /* Pointers to the body of overflow cells */
  BtShared *pBt;       /* Pointer to BtShared that this page is part of */
  u8 *aData;           /* Pointer to disk image of the page data */
  u8 *aDataEnd;        /* One byte past the end of usable data */
  u8 *aCellIdx;        /* The cell index area */
  u8 *aDataOfst;       /* Same as aData for leaves.  aData+4 for interior */
  DbPage *pDbPage;     /* Pager page handle */
  u16 (*xCellSize)(MemPage*,u8*);             /* cellSizePtr method */
  void (*xParseCell)(MemPage*,u8*,CellInfo*); /* btreeParseCell method */

};








/*
** A linked list of the following structures is stored at BtShared.pLock.
** Locks are added (or upgraded from READ_LOCK to WRITE_LOCK) when a cursor 
** is opened on the table with root page BtShared.iTable. Locks are removed
** from this list when a transaction is committed or rolled back, or when
** a btree handle is closed.
*/

    pCur->nKey = sqlite3BtreeIntegerKey(pCur);
  }else{
    /* For an index btree, save the complete key content */
    void *pKey;
    pCur->nKey = sqlite3BtreePayloadSize(pCur);
    pKey = sqlite3Malloc( pCur->nKey );
    if( pKey ){
      rc = sqlite3BtreePayload(pCur, 0, (int)pCur->nKey, pKey);
      if( rc==SQLITE_OK ){
        pCur->pKey = pKey;
      }else{
        sqlite3_free(pKey);
      }
    }else{
      rc = SQLITE_NOMEM_BKPT;

  const void *pKey,   /* Packed key if the btree is an index */
  i64 nKey,           /* Integer key for tables.  Size of pKey for indices */
  int bias,           /* Bias search to the high end */
  int *pRes           /* Write search results here */
){
  int rc;                    /* Status code */
  UnpackedRecord *pIdxKey;   /* Unpacked index key */



  if( pKey ){
    assert( nKey==(i64)(int)nKey );
    pIdxKey = sqlite3VdbeAllocUnpackedRecord(pCur->pKeyInfo);


    if( pIdxKey==0 ) return SQLITE_NOMEM_BKPT;
    sqlite3VdbeRecordUnpack(pCur->pKeyInfo, (int)nKey, pKey, pIdxKey);
    if( pIdxKey->nField==0 ){

      rc = SQLITE_CORRUPT_BKPT;
      goto moveto_done;
    }
  }else{
    pIdxKey = 0;
  }
  rc = sqlite3BtreeMovetoUnpacked(pCur, pIdxKey, nKey, bias, pRes);
moveto_done:
  if( pIdxKey ){
    sqlite3DbFree(pCur->pKeyInfo->db, pIdxKey);
  }
  return rc;
}

/*
** Restore the cursor to the position it was in (or as close to as possible)
** when saveCursorPosition() was called. Note that this call deletes the 

  assert( pPage->pBt->db!=0 );
  assert( sqlite3_mutex_held(pPage->pBt->mutex) );
  assert( pPage->pgno==sqlite3PagerPagenumber(pPage->pDbPage) );
  assert( pPage == sqlite3PagerGetExtra(pPage->pDbPage) );
  assert( pPage->aData == sqlite3PagerGetData(pPage->pDbPage) );

  if( !pPage->isInit ){
    int pc;            /* Address of a freeblock within pPage->aData[] */
    u8 hdr;            /* Offset to beginning of page header */
    u8 *data;          /* Equal to pPage->aData */
    BtShared *pBt;        /* The main btree structure */
    int usableSize;    /* Amount of usable space on each page */
    u16 cellOffset;    /* Offset from start of page to first cell pointer */
    int nFree;         /* Number of unused bytes on the page */
    int top;           /* First byte of the cell content area */

    /* Compute the total free space on the page
    ** EVIDENCE-OF: R-23588-34450 The two-byte integer at offset 1 gives the
    ** start of the first freeblock on the page, or is zero if there are no
    ** freeblocks. */
    pc = get2byte(&data[hdr+1]);
    nFree = data[hdr+7] + top;  /* Init nFree to non-freeblock free space */
    if( pc>0 ){
      u32 next, size;
      if( pc<iCellFirst ){
        /* EVIDENCE-OF: R-55530-52930 In a well-formed b-tree page, there will
        ** always be at least one cell before the first freeblock.


        */
        return SQLITE_CORRUPT_BKPT; 
      }
      while( 1 ){
        if( pc>iCellLast ){
          return SQLITE_CORRUPT_BKPT; /* Freeblock off the end of the page */
        }
        next = get2byte(&data[pc]);
        size = get2byte(&data[pc+2]);
        nFree = nFree + size;
        if( next<=pc+size+3 ) break;
        pc = next;
      }
      if( next>0 ){
        return SQLITE_CORRUPT_BKPT;  /* Freeblock not in ascending order */

      }
      if( pc+size>(unsigned int)usableSize ){
        return SQLITE_CORRUPT_BKPT;  /* Last freeblock extends past page end */
      }


    }

    /* At this point, nFree contains the sum of the offset to the start
    ** of the cell-content area plus the number of free bytes within
    ** the cell-content area. If this is greater than the usable-size
    ** of the page, then the page must be corrupted. This check also
    ** serves to verify that the offset to the start of the cell-content

  
    pBt = sqlite3MallocZero( sizeof(*pBt) );
    if( pBt==0 ){
      rc = SQLITE_NOMEM_BKPT;
      goto btree_open_out;
    }
    rc = sqlite3PagerOpen(pVfs, &pBt->pPager, zFilename,
                          sizeof(MemPage), flags, vfsFlags, pageReinit);
    if( rc==SQLITE_OK ){
      sqlite3PagerSetMmapLimit(pBt->pPager, db->szMmap);
      rc = sqlite3PagerReadFileheader(pBt->pPager,sizeof(zDbHeader),zDbHeader);
    }
    if( rc!=SQLITE_OK ){
      goto btree_open_out;
    }

  }
#endif
  *ppBtree = p;

btree_open_out:
  if( rc!=SQLITE_OK ){
    if( pBt && pBt->pPager ){
      sqlite3PagerClose(pBt->pPager, 0);
    }
    sqlite3_free(pBt);
    sqlite3_free(p);
    *ppBtree = 0;
  }else{
    sqlite3_file *pFile;

    /* If the B-Tree was successfully opened, set the pager-cache size to the
    ** default value. Except, when opening on an existing shared pager-cache,
    ** do not change the pager-cache size.
    */
    if( sqlite3BtreeSchema(p, 0, 0)==0 ){
      sqlite3PagerSetCachesize(p->pBt->pPager, SQLITE_DEFAULT_CACHE_SIZE);
    }

    pFile = sqlite3PagerFile(pBt->pPager);
    if( pFile->pMethods ){
      sqlite3OsFileControlHint(pFile, SQLITE_FCNTL_PDB, (void*)&pBt->db);
    }
  }
  if( mutexOpen ){
    assert( sqlite3_mutex_held(mutexOpen) );
    sqlite3_mutex_leave(mutexOpen);
  }
  assert( rc!=SQLITE_OK || sqlite3BtreeConnectionCount(*ppBtree)>0 );
  return rc;

  if( !p->sharable || removeFromSharingList(pBt) ){
    /* The pBt is no longer on the sharing list, so we can access
    ** it without having to hold the mutex.
    **
    ** Clean out and delete the BtShared object.
    */
    assert( !pBt->pCursor );
    sqlite3PagerClose(pBt->pPager, p->db);
    if( pBt->xFreeSchema && pBt->pSchema ){
      pBt->xFreeSchema(pBt->pSchema);
    }
    sqlite3DbFree(0, pBt->pSchema);
    freeTempSpace(pBt);
    sqlite3_free(pBt);
  }

** map entries for the overflow pages as well.
*/
static int setChildPtrmaps(MemPage *pPage){
  int i;                             /* Counter variable */
  int nCell;                         /* Number of cells in page pPage */
  int rc;                            /* Return code */
  BtShared *pBt = pPage->pBt;

  Pgno pgno = pPage->pgno;

  assert( sqlite3_mutex_held(pPage->pBt->mutex) );
  rc = btreeInitPage(pPage);
  if( rc!=SQLITE_OK ) return rc;


  nCell = pPage->nCell;

  for(i=0; i<nCell; i++){
    u8 *pCell = findCell(pPage, i);

    ptrmapPutOvflPtr(pPage, pCell, &rc);

    if( !pPage->leaf ){
      Pgno childPgno = get4byte(pCell);
      ptrmapPut(pBt, childPgno, PTRMAP_BTREE, pgno, &rc);
    }
  }

  if( !pPage->leaf ){
    Pgno childPgno = get4byte(&pPage->aData[pPage->hdrOffset+8]);
    ptrmapPut(pBt, childPgno, PTRMAP_BTREE, pgno, &rc);
  }



  return rc;
}

/*
** Somewhere on pPage is a pointer to page iFrom.  Modify this pointer so
** that it points to iTo. Parameter eType describes the type of pointer to
** be modified, as  follows:

  if( eType==PTRMAP_OVERFLOW2 ){
    /* The pointer is always the first 4 bytes of the page in this case.  */
    if( get4byte(pPage->aData)!=iFrom ){
      return SQLITE_CORRUPT_BKPT;
    }
    put4byte(pPage->aData, iTo);
  }else{

    int i;
    int nCell;
    int rc;

    rc = btreeInitPage(pPage);
    if( rc ) return rc;
    nCell = pPage->nCell;

    if( i==nCell ){
      if( eType!=PTRMAP_BTREE || 
          get4byte(&pPage->aData[pPage->hdrOffset+8])!=iFrom ){
        return SQLITE_CORRUPT_BKPT;
      }
      put4byte(&pPage->aData[pPage->hdrOffset+8], iTo);
    }


  }
  return SQLITE_OK;
}


/*
** Move the open database page pDbPage to location iFreePage in the 

** that is currently pointing to a row in a (non-empty) table.
** This is a verification routine is used only within assert() statements.
*/
SQLITE_PRIVATE int sqlite3BtreeCursorIsValid(BtCursor *pCur){
  return pCur && pCur->eState==CURSOR_VALID;
}
#endif /* NDEBUG */
SQLITE_PRIVATE int sqlite3BtreeCursorIsValidNN(BtCursor *pCur){
  assert( pCur!=0 );
  return pCur->eState==CURSOR_VALID;
}

/*
** Return the value of the integer key or "rowid" for a table btree.
** This routine is only valid for a cursor that is pointing into a
** ordinary table btree.  If the cursor points to an index btree or
** is invalid, the result of this routine is undefined.
*/

  if( rc==SQLITE_OK && amt>0 ){
    return SQLITE_CORRUPT_BKPT;
  }
  return rc;
}

/*
** Read part of the payload for the row at which that cursor pCur is currently
** pointing.  "amt" bytes will be transferred into pBuf[].  The transfer
** begins at "offset".
**
** pCur can be pointing to either a table or an index b-tree.
** If pointing to a table btree, then the content section is read.  If
** pCur is pointing to an index b-tree then the key section is read.
**
** For sqlite3BtreePayload(), the caller must ensure that pCur is pointing
** to a valid row in the table.  For sqlite3BtreePayloadChecked(), the
** cursor might be invalid or might need to be restored before being read.
**
** Return SQLITE_OK on success or an error code if anything goes
** wrong.  An error is returned if "offset+amt" is larger than
** the available payload.
*/
SQLITE_PRIVATE int sqlite3BtreePayload(BtCursor *pCur, u32 offset, u32 amt, void *pBuf){
  assert( cursorHoldsMutex(pCur) );
  assert( pCur->eState==CURSOR_VALID );
  assert( pCur->iPage>=0 && pCur->apPage[pCur->iPage] );
  assert( pCur->aiIdx[pCur->iPage]<pCur->apPage[pCur->iPage]->nCell );
  return accessPayload(pCur, offset, amt, (unsigned char*)pBuf, 0);
}
#ifndef SQLITE_OMIT_INCRBLOB









SQLITE_PRIVATE int sqlite3BtreePayloadChecked(BtCursor *pCur, u32 offset, u32 amt, void *pBuf){
  int rc;


  if ( pCur->eState==CURSOR_INVALID ){
    return SQLITE_ABORT;
  }


  assert( cursorOwnsBtShared(pCur) );
  rc = restoreCursorPosition(pCur);
  if( rc==SQLITE_OK ){
    assert( pCur->eState==CURSOR_VALID );
    assert( pCur->iPage>=0 && pCur->apPage[pCur->iPage] );
    assert( pCur->aiIdx[pCur->iPage]<pCur->apPage[pCur->iPage]->nCell );
    rc = accessPayload(pCur, offset, amt, pBuf, 0);
  }
  return rc;
}
#endif /* SQLITE_OMIT_INCRBLOB */

/*
** Return a pointer to payload information from the entry that the 
** pCur cursor is pointing to.  The pointer is to the beginning of
** the key if index btrees (pPage->intKey==0) and is the data for
** table btrees (pPage->intKey==1). The number of bytes of available
** key/data is written into *pAmt.  If *pAmt==0, then the value

      assert( pCur->skipNext!=SQLITE_OK );
      return pCur->skipNext;
    }
    sqlite3BtreeClearCursor(pCur);
  }

  if( pCur->iPage>=0 ){
    if( pCur->iPage ){
      do{
        assert( pCur->apPage[pCur->iPage]!=0 );
        releasePageNotNull(pCur->apPage[pCur->iPage--]);
      }while( pCur->iPage);
      goto skip_init;
    }
  }else if( pCur->pgnoRoot==0 ){
    pCur->eState = CURSOR_INVALID;
    return SQLITE_OK;
  }else{
    assert( pCur->iPage==(-1) );
    rc = getAndInitPage(pCur->pBtree->pBt, pCur->pgnoRoot, &pCur->apPage[0],
                        0, pCur->curPagerFlags);
    if( rc!=SQLITE_OK ){
      pCur->eState = CURSOR_INVALID;
       return rc;
    }
    pCur->iPage = 0;
    pCur->curIntKey = pCur->apPage[0]->intKey;
  }
  pRoot = pCur->apPage[0];
  assert( pRoot->pgno==pCur->pgnoRoot );

  ** in such a way that page pRoot is linked into a second b-tree table 
  ** (or the freelist).  */
  assert( pRoot->intKey==1 || pRoot->intKey==0 );
  if( pRoot->isInit==0 || (pCur->pKeyInfo==0)!=pRoot->intKey ){
    return SQLITE_CORRUPT_BKPT;
  }

skip_init:  
  pCur->aiIdx[0] = 0;
  pCur->info.nSize = 0;
  pCur->curFlags &= ~(BTCF_AtLast|BTCF_ValidNKey|BTCF_ValidOvfl);

  pRoot = pCur->apPage[0];
  if( pRoot->nCell>0 ){
    pCur->eState = CURSOR_VALID;
  }else if( !pRoot->leaf ){
    Pgno subpage;
    if( pRoot->pgno!=1 ) return SQLITE_CORRUPT_BKPT;
    subpage = get4byte(&pRoot->aData[pRoot->hdrOffset+8]);
    pCur->eState = CURSOR_VALID;

          lwr = idx+1;
          if( lwr>upr ){ c = -1; break; }
        }else if( nCellKey>intKey ){
          upr = idx-1;
          if( lwr>upr ){ c = +1; break; }
        }else{
          assert( nCellKey==intKey );


          pCur->aiIdx[pCur->iPage] = (u16)idx;
          if( !pPage->leaf ){
            lwr = idx;
            goto moveto_next_layer;
          }else{
            pCur->curFlags |= BTCF_ValidNKey;
            pCur->info.nKey = nCellKey;
            pCur->info.nSize = 0;
            *pRes = 0;
            return SQLITE_OK;

          }
        }
        assert( lwr+upr>=0 );
        idx = (lwr+upr)>>1;  /* idx = (lwr+upr)/2; */
      }
    }else{
      for(;;){

    }
    pCur->aiIdx[pCur->iPage] = (u16)lwr;
    rc = moveToChild(pCur, chldPg);
    if( rc ) break;
  }
moveto_finish:
  pCur->info.nSize = 0;
  assert( (pCur->curFlags & BTCF_ValidOvfl)==0 );
  return rc;
}


/*
** Return TRUE if the cursor is not pointing at an entry of the table.
**

        pCur->eState = CURSOR_INVALID;
        *pRes = 1;
        return SQLITE_OK;
      }
      moveToParent(pCur);
    }
    assert( pCur->info.nSize==0 );
    assert( (pCur->curFlags & (BTCF_ValidOvfl))==0 );

    pCur->aiIdx[pCur->iPage]--;
    pPage = pCur->apPage[pCur->iPage];
    if( pPage->intKey && !pPage->leaf ){
      rc = sqlite3BtreePrevious(pCur, pRes);
    }else{
      rc = SQLITE_OK;

** Free any overflow pages associated with the given Cell.  Write the
** local Cell size (the number of bytes on the original page, omitting
** overflow) into *pnSize.
*/
static int clearCell(
  MemPage *pPage,          /* The page that contains the Cell */
  unsigned char *pCell,    /* First byte of the Cell */
  CellInfo *pInfo          /* Size information about the cell */
){
  BtShared *pBt = pPage->pBt;

  Pgno ovflPgno;
  int rc;
  int nOvfl;
  u32 ovflPageSize;

  assert( sqlite3_mutex_held(pPage->pBt->mutex) );
  pPage->xParseCell(pPage, pCell, pInfo);

  if( pInfo->nLocal==pInfo->nPayload ){
    return SQLITE_OK;  /* No overflow pages. Return without doing anything */
  }
  if( pCell+pInfo->nSize-1 > pPage->aData+pPage->maskPage ){
    return SQLITE_CORRUPT_BKPT;  /* Cell extends past end of page */
  }
  ovflPgno = get4byte(pCell + pInfo->nSize - 4);
  assert( pBt->usableSize > 4 );
  ovflPageSize = pBt->usableSize - 4;
  nOvfl = (pInfo->nPayload - pInfo->nLocal + ovflPageSize - 1)/ovflPageSize;
  assert( nOvfl>0 || 
    (CORRUPT_DB && (pInfo->nPayload + ovflPageSize)<ovflPageSize)
  );
  while( nOvfl-- ){
    Pgno iNext = 0;
    MemPage *pOvfl = 0;
    if( ovflPgno<2 || ovflPgno>btreePagecount(pBt) ){
      /* 0 is not a legal page number and page 1 cannot be an 
      ** overflow page. Therefore if ovflPgno<2 or past the end of the 

  u32 pc;         /* Offset to cell content of cell being deleted */
  u8 *data;       /* pPage->aData */
  u8 *ptr;        /* Used to move bytes around within data[] */
  int rc;         /* The return code */
  int hdr;        /* Beginning of the header.  0 most pages.  100 page 1 */

  if( *pRC ) return;

  assert( idx>=0 && idx<pPage->nCell );
  assert( CORRUPT_DB || sz==cellSize(pPage, idx) );
  assert( sqlite3PagerIswriteable(pPage->pDbPage) );
  assert( sqlite3_mutex_held(pPage->pBt->mutex) );
  data = pPage->aData;
  ptr = &pPage->aCellIdx[2*idx];
  pc = get2byte(ptr);

      memcpy(pTemp, pCell, sz);
      pCell = pTemp;
    }
    if( iChild ){
      put4byte(pCell, iChild);
    }
    j = pPage->nOverflow++;
    /* Comparison against ArraySize-1 since we hold back one extra slot
    ** as a contingency.  In other words, never need more than 3 overflow
    ** slots but 4 are allocated, just to be safe. */
    assert( j < ArraySize(pPage->apOvfl)-1 );
    pPage->apOvfl[j] = pCell;
    pPage->aiOvfl[j] = (u16)i;

    /* When multiple overflows occur, they are always sequential and in
    ** sorted order.  This invariants arise because multiple overflows can
    ** only occur when inserting divider cells into the parent page during
    ** balancing, and the dividers are adjacent and sorted.

    if( rc ){
      memset(apOld, 0, (i+1)*sizeof(MemPage*));
      goto balance_cleanup;
    }
    nMaxCells += 1+apOld[i]->nCell+apOld[i]->nOverflow;
    if( (i--)==0 ) break;

    if( pParent->nOverflow && i+nxDiv==pParent->aiOvfl[0] ){
      apDiv[i] = pParent->apOvfl[0];
      pgno = get4byte(apDiv[i]);
      szNew[i] = pParent->xCellSize(pParent, apDiv[i]);
      pParent->nOverflow = 0;
    }else{
      apDiv[i] = findCell(pParent, i+nxDiv-pParent->nOverflow);
      pgno = get4byte(apDiv[i]);

** hold the content of the row.
**
** For an index btree (used for indexes and WITHOUT ROWID tables), the
** key is an arbitrary byte sequence stored in pX.pKey,nKey.  The 
** pX.pData,nData,nZero fields must be zero.
**
** If the seekResult parameter is non-zero, then a successful call to
** MovetoUnpacked() to seek cursor pCur to (pKey,nKey) has already
** been performed.  In other words, if seekResult!=0 then the cursor
** is currently pointing to a cell that will be adjacent to the cell
** to be inserted.  If seekResult<0 then pCur points to a cell that is
** smaller then (pKey,nKey).  If seekResult>0 then pCur points to a cell
** that is larger than (pKey,nKey).

**

** If seekResult==0, that means pCur is pointing at some unknown location.
** In that case, this routine must seek the cursor to the correct insertion
** point for (pKey,nKey) before doing the insertion.  For index btrees,
** if pX->nMem is non-zero, then pX->aMem contains pointers to the unpacked
** key values and pX->aMem can be used instead of pX->pKey to avoid having
** to decode the key.
*/
SQLITE_PRIVATE int sqlite3BtreeInsert(
  BtCursor *pCur,                /* Insert data into the table of this cursor */
  const BtreePayload *pX,        /* Content of the row to be inserted */
  int appendBias,                /* True if this is likely an append */
  int seekResult                 /* Result of prior MovetoUnpacked() call */
){

    /* If this is an insert into a table b-tree, invalidate any incrblob 
    ** cursors open on the row being replaced */
    invalidateIncrblobCursors(p, pX->nKey, 0);

    /* If the cursor is currently on the last row and we are appending a
    ** new row onto the end, set the "loc" to avoid an unnecessary
    ** btreeMoveto() call */
    if( (pCur->curFlags&BTCF_ValidNKey)!=0 && pX->nKey==pCur->info.nKey ){
      loc = 0;
    }else if( (pCur->curFlags&BTCF_ValidNKey)!=0 && pX->nKey>0
               && pCur->info.nKey==pX->nKey-1 ){
      loc = -1;
    }else if( loc==0 ){
      rc = sqlite3BtreeMovetoUnpacked(pCur, 0, pX->nKey, appendBias, &loc);
      if( rc ) return rc;
    }
  }else if( loc==0 ){
    if( pX->nMem ){
      UnpackedRecord r;
      r.pKeyInfo = pCur->pKeyInfo;
      r.aMem = pX->aMem;
      r.nField = pX->nMem;
      r.default_rc = 0;
      r.errCode = 0;
      r.r1 = 0;
      r.r2 = 0;
      r.eqSeen = 0;
      rc = sqlite3BtreeMovetoUnpacked(pCur, &r, 0, appendBias, &loc);
    }else{
      rc = btreeMoveto(pCur, pX->pKey, pX->nKey, appendBias, &loc);
    }
    if( rc ) return rc;
  }
  assert( pCur->eState==CURSOR_VALID || (pCur->eState==CURSOR_INVALID && loc) );

  pPage = pCur->apPage[pCur->iPage];
  assert( pPage->intKey || pX->nKey>=0 );
  assert( pPage->leaf || !pPage->intKey );

  TRACE(("INSERT: table=%d nkey=%lld ndata=%d page=%d %s\n",
          pCur->pgnoRoot, pX->nKey, pX->nData, pPage->pgno,
          loc==0 ? "overwrite" : "new entry"));
  assert( pPage->isInit );
  newCell = pBt->pTmpSpace;
  assert( newCell!=0 );
  rc = fillInCell(pPage, newCell, pX, &szNew);
  if( rc ) goto end_insert;
  assert( szNew==pPage->xCellSize(pPage, newCell) );
  assert( szNew <= MX_CELL_SIZE(pBt) );
  idx = pCur->aiIdx[pCur->iPage];
  if( loc==0 ){
    CellInfo info;
    assert( idx<pPage->nCell );
    rc = sqlite3PagerWrite(pPage->pDbPage);
    if( rc ){
      goto end_insert;
    }
    oldCell = findCell(pPage, idx);
    if( !pPage->leaf ){
      memcpy(newCell, oldCell, 4);
    }
    rc = clearCell(pPage, oldCell, &info);
    if( info.nSize==szNew && info.nLocal==info.nPayload ){
      /* Overwrite the old cell with the new if they are the same size.
      ** We could also try to do this if the old cell is smaller, then add
      ** the leftover space to the free list.  But experiments show that
      ** doing that is no faster then skipping this optimization and just
      ** calling dropCell() and insertCell(). */
      assert( rc==SQLITE_OK ); /* clearCell never fails when nLocal==nPayload */
      if( oldCell+szNew > pPage->aDataEnd ) return SQLITE_CORRUPT_BKPT;
      memcpy(oldCell, newCell, szNew);
      return SQLITE_OK;
    }
    dropCell(pPage, idx, info.nSize, &rc);
    if( rc ) goto end_insert;
  }else if( loc<0 && pPage->nCell>0 ){
    assert( pPage->leaf );
    idx = ++pCur->aiIdx[pCur->iPage];
  }else{
    assert( pPage->leaf );
  }

  Btree *p = pCur->pBtree;
  BtShared *pBt = p->pBt;              
  int rc;                              /* Return code */
  MemPage *pPage;                      /* Page to delete cell from */
  unsigned char *pCell;                /* Pointer to cell to delete */
  int iCellIdx;                        /* Index of cell to delete */
  int iCellDepth;                      /* Depth of node containing pCell */ 
  CellInfo info;                       /* Size of the cell being deleted */
  int bSkipnext = 0;                   /* Leaf cursor in SKIPNEXT state */
  u8 bPreserve = flags & BTREE_SAVEPOSITION;  /* Keep cursor valid */

  assert( cursorOwnsBtShared(pCur) );
  assert( pBt->inTransaction==TRANS_WRITE );
  assert( (pBt->btsFlags & BTS_READ_ONLY)==0 );
  assert( pCur->curFlags & BTCF_WriteFlag );

  }

  /* Make the page containing the entry to be deleted writable. Then free any
  ** overflow pages associated with the entry and finally remove the cell
  ** itself from within the page.  */
  rc = sqlite3PagerWrite(pPage->pDbPage);
  if( rc ) return rc;
  rc = clearCell(pPage, pCell, &info);
  dropCell(pPage, iCellIdx, info.nSize, &rc);
  if( rc ) return rc;

  /* If the cell deleted was not located on a leaf page, then the cursor
  ** is currently pointing to the largest entry in the sub-tree headed
  ** by the child-page of the cell that was just deleted from an internal
  ** node. The cell from the leaf node needs to be moved to the internal
  ** node to replace the deleted cell.  */

  int *pnChange            /* Add number of Cells freed to this counter */
){
  MemPage *pPage;
  int rc;
  unsigned char *pCell;
  int i;
  int hdr;
  CellInfo info;

  assert( sqlite3_mutex_held(pBt->mutex) );
  if( pgno>btreePagecount(pBt) ){
    return SQLITE_CORRUPT_BKPT;
  }
  rc = getAndInitPage(pBt, pgno, &pPage, 0, 0);
  if( rc ) return rc;
  if( pPage->bBusy ){
    rc = SQLITE_CORRUPT_BKPT;
    goto cleardatabasepage_out;
  }
  pPage->bBusy = 1;
  hdr = pPage->hdrOffset;
  for(i=0; i<pPage->nCell; i++){
    pCell = findCell(pPage, i);
    if( !pPage->leaf ){
      rc = clearDatabasePage(pBt, get4byte(pCell), 1, pnChange);
      if( rc ) goto cleardatabasepage_out;
    }
    rc = clearCell(pPage, pCell, &info);
    if( rc ) goto cleardatabasepage_out;
  }
  if( !pPage->leaf ){
    rc = clearDatabasePage(pBt, get4byte(&pPage->aData[hdr+8]), 1, pnChange);
    if( rc ) goto cleardatabasepage_out;
  }else if( pnChange ){
    assert( pPage->intKey || CORRUPT_DB );

static int btreeDropTable(Btree *p, Pgno iTable, int *piMoved){
  int rc;
  MemPage *pPage = 0;
  BtShared *pBt = p->pBt;

  assert( sqlite3BtreeHoldsMutex(p) );
  assert( p->inTrans==TRANS_WRITE );
  assert( iTable>=2 );





















  rc = btreeGetPage(pBt, (Pgno)iTable, &pPage, 0);
  if( rc ) return rc;
  rc = sqlite3BtreeClearTable(p, iTable, 0);
  if( rc ){
    releasePage(pPage);
    return rc;

  int rc = SQLITE_OK;
  if( p ){
    BtShared *pBt = p->pBt;
    sqlite3BtreeEnter(p);
    if( pBt->inTransaction!=TRANS_NONE ){
      rc = SQLITE_LOCKED;
    }else{
      rc = sqlite3PagerCheckpoint(pBt->pPager, p->db, eMode, pnLog, pnCkpt);
    }
    sqlite3BtreeLeave(p);
  }
  return rc;
}
#endif

  }

  return SQLITE_OK;
}

/*
** Move data out of a btree key or data field and into a Mem structure.
** The data is payload from the entry that pCur is currently pointing
** to.  offset and amt determine what portion of the data or key to retrieve.

** The result is written into the pMem element.
**
** The pMem object must have been initialized.  This routine will use
** pMem->zMalloc to hold the content from the btree, if possible.  New
** pMem->zMalloc space will be allocated if necessary.  The calling routine
** is responsible for making sure that the pMem object is eventually
** destroyed.
**
** If this routine fails for any reason (malloc returns NULL or unable
** to read from the disk) then the pMem is left in an inconsistent state.
*/
static SQLITE_NOINLINE int vdbeMemFromBtreeResize(
  BtCursor *pCur,   /* Cursor pointing at record to retrieve. */
  u32 offset,       /* Offset from the start of data to return bytes from. */
  u32 amt,          /* Number of bytes to return. */

  Mem *pMem         /* OUT: Return data in this Mem structure. */
){
  int rc;
  pMem->flags = MEM_Null;
  if( SQLITE_OK==(rc = sqlite3VdbeMemClearAndResize(pMem, amt+2)) ){

    rc = sqlite3BtreePayload(pCur, offset, amt, pMem->z);



    if( rc==SQLITE_OK ){
      pMem->z[amt] = 0;
      pMem->z[amt+1] = 0;
      pMem->flags = MEM_Blob|MEM_Term;
      pMem->n = (int)amt;
    }else{
      sqlite3VdbeMemRelease(pMem);
    }
  }
  return rc;
}
SQLITE_PRIVATE int sqlite3VdbeMemFromBtree(
  BtCursor *pCur,   /* Cursor pointing at record to retrieve. */
  u32 offset,       /* Offset from the start of data to return bytes from. */
  u32 amt,          /* Number of bytes to return. */

  Mem *pMem         /* OUT: Return data in this Mem structure. */
){
  char *zData;        /* Data from the btree layer */
  u32 available = 0;  /* Number of bytes available on the local btree page */
  int rc = SQLITE_OK; /* Return code */

  assert( sqlite3BtreeCursorIsValid(pCur) );
  assert( !VdbeMemDynamic(pMem) );

  /* Note: the calls to BtreeKeyFetch() and DataFetch() below assert() 
  ** that both the BtShared and database handle mutexes are held. */
  assert( (pMem->flags & MEM_RowSet)==0 );
  zData = (char *)sqlite3BtreePayloadFetch(pCur, &available);
  assert( zData!=0 );

  if( offset+amt<=available ){
    pMem->z = &zData[offset];
    pMem->flags = MEM_Blob|MEM_Ephem;
    pMem->n = (int)amt;
  }else{
    rc = vdbeMemFromBtreeResize(pCur, offset, amt, pMem);
  }

  return rc;
}

/*
** The pVal argument is known to be a value other than NULL.

        pVal->u.i = -pVal->u.i;
      }
      sqlite3ValueApplyAffinity(pVal, affinity, enc);
    }
  }else if( op==TK_NULL ){
    pVal = valueNew(db, pCtx);
    if( pVal==0 ) goto no_mem;
    sqlite3VdbeMemNumerify(pVal);
  }
#ifndef SQLITE_OMIT_BLOB_LITERAL
  else if( op==TK_BLOB ){
    int nVal;
    assert( pExpr->u.zToken[0]=='x' || pExpr->u.zToken[0]=='X' );
    assert( pExpr->u.zToken[1]=='\'' );
    pVal = valueNew(db, pCtx);

  int op,             /* The new opcode */
  int p1,             /* The P1 operand */
  int p2,             /* The P2 operand */
  int p3,             /* The P3 operand */
  int p4              /* The P4 operand as an integer */
){
  int addr = sqlite3VdbeAddOp3(p, op, p1, p2, p3);
  if( p->db->mallocFailed==0 ){
    VdbeOp *pOp = &p->aOp[addr];
    pOp->p4type = P4_INT32;
    pOp->p4.i = p4;
  }
  return addr;
}

/* Insert the end of a co-routine
*/
SQLITE_PRIVATE void sqlite3VdbeEndCoroutine(Vdbe *v, int regYield){
  sqlite3VdbeAddOp1(v, OP_EndCoroutine, regYield);

    }
#ifdef SQLITE_ENABLE_CURSOR_HINTS
    case P4_EXPR: {
      sqlite3ExprDelete(db, (Expr*)p4);
      break;
    }
#endif




    case P4_FUNCDEF: {
      freeEphemeralFunction(db, (FuncDef*)p4);
      break;
    }
    case P4_MEM: {
      if( db->pnBytesFreed==0 ){
        sqlite3ValueFree((sqlite3_value*)p4);

  }else if( zP4!=0 ){
    assert( n<0 );
    pOp->p4.p = (void*)zP4;
    pOp->p4type = (signed char)n;
    if( n==P4_VTAB ) sqlite3VtabLock((VTable*)zP4);
  }
}

/*
** Change the P4 operand of the most recently coded instruction 
** to the value defined by the arguments.  This is a high-speed
** version of sqlite3VdbeChangeP4().
**
** The P4 operand must not have been previously defined.  And the new
** P4 must not be P4_INT32.  Use sqlite3VdbeChangeP4() in either of
** those cases.
*/
SQLITE_PRIVATE void sqlite3VdbeAppendP4(Vdbe *p, void *pP4, int n){
  VdbeOp *pOp;
  assert( n!=P4_INT32 && n!=P4_VTAB );
  assert( n<=0 );
  if( p->db->mallocFailed ){
    freeP4(p->db, n, pP4);
  }else{
    assert( pP4!=0 );
    assert( p->nOp>0 );
    pOp = &p->aOp[p->nOp-1];
    assert( pOp->p4type==P4_NOTUSED );
    pOp->p4type = n;
    pOp->p4.p = pP4;
  }
}

/*
** Set the P4 on the most recently added opcode to the KeyInfo for the
** index given.
*/
SQLITE_PRIVATE void sqlite3VdbeSetP4KeyInfo(Parse *pParse, Index *pIdx){
  Vdbe *v = pParse->pVdbe;
  KeyInfo *pKeyInfo;
  assert( v!=0 );
  assert( pIdx!=0 );
  pKeyInfo = sqlite3KeyInfoOfIndex(pParse, pIdx);
  if( pKeyInfo ) sqlite3VdbeAppendP4(v, pKeyInfo, P4_KEYINFO);
}

#ifdef SQLITE_ENABLE_EXPLAIN_COMMENTS
/*
** Change the comment on the most recently coded instruction.  Or
** insert a No-op and add the comment to that new instruction.  This
** makes the code easier to read during debugging.  None of this happens

      break;
    }
    case P4_FUNCDEF: {
      FuncDef *pDef = pOp->p4.pFunc;
      sqlite3XPrintf(&x, "%s(%d)", pDef->zName, pDef->nArg);
      break;
    }
#if defined(SQLITE_DEBUG) || defined(VDBE_PROFILE)
    case P4_FUNCCTX: {
      FuncDef *pDef = pOp->p4.pCtx->pFunc;
      sqlite3XPrintf(&x, "%s(%d)", pDef->zName, pDef->nArg);
      break;
    }
#endif
    case P4_INT64: {

    p->anExec = allocSpace(&x, p->anExec, p->nOp*sizeof(i64));
#endif
    if( x.nNeeded==0 ) break;
    x.pSpace = p->pFree = sqlite3DbMallocRawNN(db, x.nNeeded);
    x.nFree = x.nNeeded;
  }while( !db->mallocFailed );

  p->pVList = pParse->pVList;

  pParse->pVList =  0;

  p->explain = pParse->explain;
  if( db->mallocFailed ){
    p->nVar = 0;
    p->nCursor = 0;
    p->nMem = 0;
  }else{
    p->nCursor = nCursor;

** Close a VDBE cursor and release all the resources that cursor 
** happens to hold.
*/
SQLITE_PRIVATE void sqlite3VdbeFreeCursor(Vdbe *p, VdbeCursor *pCx){
  if( pCx==0 ){
    return;
  }
  assert( pCx->pBtx==0 || pCx->eCurType==CURTYPE_BTREE );
  switch( pCx->eCurType ){
    case CURTYPE_SORTER: {
      sqlite3VdbeSorterClose(p->db, pCx);
      break;
    }
    case CURTYPE_BTREE: {
      if( pCx->pBtx ){
        sqlite3BtreeClose(pCx->pBtx);
        /* The pCx->pCursor will be close automatically, if it exists, by
        ** the call above. */
      }else{
        assert( pCx->uc.pCursor!=0 );
        sqlite3BtreeCloseCursor(pCx->uc.pCursor);
      }
      break;

**
** The difference between this function and sqlite3VdbeDelete() is that
** VdbeDelete() also unlinks the Vdbe from the list of VMs associated with
** the database connection and frees the object itself.
*/
SQLITE_PRIVATE void sqlite3VdbeClearObject(sqlite3 *db, Vdbe *p){
  SubProgram *pSub, *pNext;

  assert( p->db==0 || p->db==db );
  releaseMemArray(p->aColName, p->nResColumn*COLNAME_N);
  for(pSub=p->pProgram; pSub; pSub=pNext){
    pNext = pSub->pNext;
    vdbeFreeOpArray(db, pSub->aOp, pSub->nOp);
    sqlite3DbFree(db, pSub);
  }
  if( p->magic!=VDBE_MAGIC_INIT ){
    releaseMemArray(p->aVar, p->nVar);

    sqlite3DbFree(db, p->pVList);
    sqlite3DbFree(db, p->pFree);
  }
  vdbeFreeOpArray(db, p->aOp, p->nOp);
  sqlite3DbFree(db, p->aColName);
  sqlite3DbFree(db, p->zSql);
#ifdef SQLITE_ENABLE_STMT_SCANSTATUS
  {
    int i;
    for(i=0; i<p->nScan; i++){
      sqlite3DbFree(db, p->aScan[i].zName);
    }
    sqlite3DbFree(db, p->aScan);
  }
#endif
}

/*
** Delete an entire VDBE.
*/
SQLITE_PRIVATE void sqlite3VdbeDelete(Vdbe *p){

** be eventually freed by the caller using sqlite3DbFree(). Or, if the 
** allocation comes from the pSpace/szSpace buffer, *ppFree is set to NULL
** before returning.
**
** If an OOM error occurs, NULL is returned.
*/
SQLITE_PRIVATE UnpackedRecord *sqlite3VdbeAllocUnpackedRecord(
  KeyInfo *pKeyInfo               /* Description of the record */



){
  UnpackedRecord *p;              /* Unpacked record to return */

  int nByte;                      /* Number of bytes required for *p */






  nByte = ROUND8(sizeof(UnpackedRecord)) + sizeof(Mem)*(pKeyInfo->nField+1);

  p = (UnpackedRecord *)sqlite3DbMallocRaw(pKeyInfo->db, nByte);

  if( !p ) return 0;





  p->aMem = (Mem*)&((char*)p)[ROUND8(sizeof(UnpackedRecord))];
  assert( pKeyInfo->aSortOrder!=0 );
  p->pKeyInfo = pKeyInfo;
  p->nField = pKeyInfo->nField + 1;
  return p;
}

  */
  assert( sqlite3BtreeCursorIsValid(pCur) );
  nCellKey = sqlite3BtreePayloadSize(pCur);
  assert( (nCellKey & SQLITE_MAX_U32)==(u64)nCellKey );

  /* Read in the complete content of the index entry */
  sqlite3VdbeMemInit(&m, db, 0);
  rc = sqlite3VdbeMemFromBtree(pCur, 0, (u32)nCellKey, &m);
  if( rc ){
    return rc;
  }

  /* The index entry must begin with a header size */
  (void)getVarint32((u8*)m.z, szHdr);
  testcase( szHdr==3 );

  /* nCellKey will always be between 0 and 0xffffffff because of the way
  ** that btreeParseCellPtr() and sqlite3GetVarint32() are implemented */
  if( nCellKey<=0 || nCellKey>0x7fffffff ){
    *res = 0;
    return SQLITE_CORRUPT_BKPT;
  }
  sqlite3VdbeMemInit(&m, db, 0);
  rc = sqlite3VdbeMemFromBtree(pCur, 0, (u32)nCellKey, &m);
  if( rc ){
    return rc;
  }
  *res = sqlite3VdbeRecordCompare(m.n, m.z, pUnpacked);
  sqlite3VdbeMemRelease(&m);
  return SQLITE_OK;
}

** Return the name of a wildcard parameter.  Return NULL if the index
** is out of range or if the wildcard is unnamed.
**
** The result is always UTF-8.
*/
SQLITE_API const char *sqlite3_bind_parameter_name(sqlite3_stmt *pStmt, int i){
  Vdbe *p = (Vdbe*)pStmt;

  if( p==0 ) return 0;

  return sqlite3VListNumToName(p->pVList, i);
}

/*
** Given a wildcard parameter name, return the index of the variable
** with that name.  If there is no variable with the given name,
** return 0.
*/
SQLITE_PRIVATE int sqlite3VdbeParameterIndex(Vdbe *p, const char *zName, int nName){

  if( p==0 || zName==0 ) return 0;
  return sqlite3VListNameToNum(p->pVList, zName, nName);










}
SQLITE_API int sqlite3_bind_parameter_index(sqlite3_stmt *pStmt, const char *zName){
  return sqlite3VdbeParameterIndex((Vdbe*)pStmt, zName, sqlite3Strlen30(zName));
}

/*
** Transfer all bindings from the first statement over to the second.

** if successful, or a NULL pointer if an OOM error is encountered.
*/
static UnpackedRecord *vdbeUnpackRecord(
  KeyInfo *pKeyInfo, 
  int nKey, 
  const void *pKey
){

  UnpackedRecord *pRet;           /* Return value */

  pRet = sqlite3VdbeAllocUnpackedRecord(pKeyInfo);
  if( pRet ){
    memset(pRet->aMem, 0, sizeof(Mem)*(pKeyInfo->nField+1));
    sqlite3VdbeRecordUnpack(pKeyInfo, nKey, pKey, pRet);
  }
  return pRet;
}

  if( p->pUnpacked==0 ){
    u32 nRec;
    u8 *aRec;

    nRec = sqlite3BtreePayloadSize(p->pCsr->uc.pCursor);
    aRec = sqlite3DbMallocRaw(db, nRec);
    if( !aRec ) goto preupdate_old_out;
    rc = sqlite3BtreePayload(p->pCsr->uc.pCursor, 0, nRec, aRec);
    if( rc==SQLITE_OK ){
      p->pUnpacked = vdbeUnpackRecord(&p->keyinfo, nRec, aRec);
      if( !p->pUnpacked ) rc = SQLITE_NOMEM;
    }
    if( rc!=SQLITE_OK ){
      sqlite3DbFree(db, aRec);
      goto preupdate_old_out;

SQLITE_API int sqlite3_found_count = 0;
#endif

/*
** Test a register to see if it exceeds the current maximum blob size.
** If it does, record the new maximum blob size.
*/
#if defined(SQLITE_TEST) && !defined(SQLITE_UNTESTABLE)
# define UPDATE_MAX_BLOBSIZE(P)  updateMaxBlobsize(P)
#else
# define UPDATE_MAX_BLOBSIZE(P)
#endif

/*
** Invoke the VDBE coverage callback, if that callback is defined.  This

  assert( iCur>=0 && iCur<p->nCursor );
  if( p->apCsr[iCur] ){ /*OPTIMIZATION-IF-FALSE*/
    sqlite3VdbeFreeCursor(p, p->apCsr[iCur]);
    p->apCsr[iCur] = 0;
  }
  if( SQLITE_OK==sqlite3VdbeMemClearAndResize(pMem, nByte) ){
    p->apCsr[iCur] = pCx = (VdbeCursor*)pMem->z;
    memset(pCx, 0, offsetof(VdbeCursor,pAltCursor));
    pCx->eCurType = eCurType;
    pCx->iDb = iDb;
    pCx->nField = nField;
    pCx->aOffset = &pCx->aType[nField];
    if( eCurType==CURTYPE_BTREE ){
      pCx->uc.pCursor = (BtCursor*)
          &pMem->z[ROUND8(sizeof(VdbeCursor))+2*sizeof(u32)*nField];

    aMem = p->aMem;
    pOp = &aOp[pcx];
    break;
  }
  p->rc = pOp->p1;
  p->errorAction = (u8)pOp->p2;
  p->pc = pcx;
  assert( pOp->p5<=4 );
  if( p->rc ){
    if( pOp->p5 ){
      static const char * const azType[] = { "NOT NULL", "UNIQUE", "CHECK",
                                             "FOREIGN KEY" };
      testcase( pOp->p5==1 );
      testcase( pOp->p5==2 );
      testcase( pOp->p5==3 );

** If the parameter is named, then its name appears in P4.
** The P4 value is used by sqlite3_bind_parameter_name().
*/
case OP_Variable: {            /* out2 */
  Mem *pVar;       /* Value being transferred */

  assert( pOp->p1>0 && pOp->p1<=p->nVar );
  assert( pOp->p4.z==0 || pOp->p4.z==sqlite3VListNumToName(p->pVList,pOp->p1) );
  pVar = &p->aVar[pOp->p1 - 1];
  if( sqlite3VdbeMemTooBig(pVar) ){
    goto too_big;
  }
  pOut = out2Prerelease(p, pOp);
  sqlite3VdbeMemShallowCopy(pOut, pVar, MEM_Static);
  UPDATE_MAX_BLOBSIZE(pOut);

      /* If SQLITE_NULLEQ is set (which will only happen if the operator is
      ** OP_Eq or OP_Ne) then take the jump or not depending on whether
      ** or not both operands are null.
      */
      assert( pOp->opcode==OP_Eq || pOp->opcode==OP_Ne );
      assert( (flags1 & MEM_Cleared)==0 );
      assert( (pOp->p5 & SQLITE_JUMPIFNULL)==0 );

      if( (flags1&flags3&MEM_Null)!=0
       && (flags3&MEM_Cleared)==0
      ){
        res = 0;  /* Operands are equal */
      }else{
        res = 1;  /* Operands are not equal */
      }
    }else{

  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
  assert( pC!=0 );
  assert( p2<pC->nField );
  aOffset = pC->aOffset;
  assert( pC->eCurType!=CURTYPE_VTAB );
  assert( pC->eCurType!=CURTYPE_PSEUDO || pC->nullRow );
  assert( pC->eCurType!=CURTYPE_SORTER );


  if( pC->cacheStatus!=p->cacheCtr ){                /*OPTIMIZATION-IF-FALSE*/
    if( pC->nullRow ){
      if( pC->eCurType==CURTYPE_PSEUDO ){
        assert( pC->uc.pseudoTableReg>0 );
        pReg = &aMem[pC->uc.pseudoTableReg];
        assert( pReg->flags & MEM_Blob );
        assert( memIsValid(pReg) );
        pC->payloadSize = pC->szRow = avail = pReg->n;
        pC->aRow = (u8*)pReg->z;
      }else{
        sqlite3VdbeMemSetNull(pDest);
        goto op_column_out;
      }
    }else{
      pCrsr = pC->uc.pCursor;
      assert( pC->eCurType==CURTYPE_BTREE );
      assert( pCrsr );
      assert( sqlite3BtreeCursorIsValid(pCrsr) );
      pC->payloadSize = sqlite3BtreePayloadSize(pCrsr);
      pC->aRow = sqlite3BtreePayloadFetch(pCrsr, &avail);
      assert( avail<=65536 );  /* Maximum page size is 64KiB */
      if( pC->payloadSize <= (u32)avail ){

    /* If there is more header available for parsing in the record, try
    ** to extract additional fields up through the p2+1-th field 
    */
    if( pC->iHdrOffset<aOffset[0] ){
      /* Make sure zData points to enough of the record to cover the header. */
      if( pC->aRow==0 ){
        memset(&sMem, 0, sizeof(sMem));
        rc = sqlite3VdbeMemFromBtree(pC->uc.pCursor, 0, aOffset[0], &sMem);
        if( rc!=SQLITE_OK ) goto abort_due_to_error;
        zData = (u8*)sMem.z;
      }else{
        zData = pC->aRow;
      }
  
      /* Fill in pC->aType[i] and aOffset[i] values through the p2-th field. */

      **    2. the length(X) function if X is a blob, and
      **    3. if the content length is zero.
      ** So we might as well use bogus content rather than reading
      ** content from disk. */
      static u8 aZero[8];  /* This is the bogus content */
      sqlite3VdbeSerialGet(aZero, t, pDest);
    }else{
      rc = sqlite3VdbeMemFromBtree(pC->uc.pCursor, aOffset[p2], len, pDest);

      if( rc!=SQLITE_OK ) goto abort_due_to_error;
      sqlite3VdbeSerialGet((const u8*)pDest->z, t, pDest);
      pDest->flags &= ~MEM_Ephem;
    }
  }

op_column_out:

      SQLITE_OPEN_TRANSIENT_DB;
  assert( pOp->p1>=0 );
  assert( pOp->p2>=0 );
  pCx = allocateCursor(p, pOp->p1, pOp->p2, -1, CURTYPE_BTREE);
  if( pCx==0 ) goto no_mem;
  pCx->nullRow = 1;
  pCx->isEphemeral = 1;
  rc = sqlite3BtreeOpen(db->pVfs, 0, db, &pCx->pBtx, 
                        BTREE_OMIT_JOURNAL | BTREE_SINGLE | pOp->p5, vfsFlags);
  if( rc==SQLITE_OK ){
    rc = sqlite3BtreeBeginTrans(pCx->pBtx, 1);
  }
  if( rc==SQLITE_OK ){
    /* If a transient index is required, create it by calling
    ** sqlite3BtreeCreateTable() with the BTREE_BLOBKEY flag before
    ** opening it. If a transient table is required, just use the
    ** automatically created table with root-page 1 (an BLOB_INTKEY table).
    */
    if( (pCx->pKeyInfo = pKeyInfo = pOp->p4.pKeyInfo)!=0 ){
      int pgno;
      assert( pOp->p4type==P4_KEYINFO );
      rc = sqlite3BtreeCreateTable(pCx->pBtx, &pgno, BTREE_BLOBKEY | pOp->p5); 
      if( rc==SQLITE_OK ){
        assert( pgno==MASTER_ROOT+1 );
        assert( pKeyInfo->db==db );
        assert( pKeyInfo->enc==ENC(db) );

        rc = sqlite3BtreeCursor(pCx->pBtx, pgno, BTREE_WRCSR,
                                pKeyInfo, pCx->uc.pCursor);
      }
      pCx->isTable = 0;
    }else{
      rc = sqlite3BtreeCursor(pCx->pBtx, MASTER_ROOT, BTREE_WRCSR,
                              0, pCx->uc.pCursor);
      pCx->isTable = 1;
    }
  }
  if( rc ) goto abort_due_to_error;
  pCx->isOrdered = (pOp->p5!=BTREE_UNORDERED);
  break;

  pC->nullRow = 0;
#ifdef SQLITE_DEBUG
  pC->seekOp = pOp->opcode;
#endif

  if( pC->isTable ){
    /* The BTREE_SEEK_EQ flag is only set on index cursors */
    assert( sqlite3BtreeCursorHasHint(pC->uc.pCursor, BTREE_SEEK_EQ)==0
              || CORRUPT_DB );

    /* The input value in P3 might be of any type: integer, real, string,
    ** blob, or NULL.  But it needs to be an integer before we can do
    ** the seek, so convert it. */
    pIn3 = &aMem[pOp->p3];
    if( (pIn3->flags & (MEM_Int|MEM_Real|MEM_Str))==MEM_Str ){
      applyNumericAffinity(pIn3, 0);

case OP_NotFound:       /* jump, in3 */
case OP_Found: {        /* jump, in3 */
  int alreadyExists;
  int takeJump;
  int ii;
  VdbeCursor *pC;
  int res;
  UnpackedRecord *pFree;
  UnpackedRecord *pIdxKey;
  UnpackedRecord r;


#ifdef SQLITE_TEST
  if( pOp->opcode!=OP_NoConflict ) sqlite3_found_count++;
#endif

  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
  assert( pOp->p4type==P4_INT32 );
  pC = p->apCsr[pOp->p1];
  assert( pC!=0 );
#ifdef SQLITE_DEBUG
  pC->seekOp = pOp->opcode;
#endif
  pIn3 = &aMem[pOp->p3];
  assert( pC->eCurType==CURTYPE_BTREE );
  assert( pC->uc.pCursor!=0 );
  assert( pC->isTable==0 );

  if( pOp->p4.i>0 ){
    r.pKeyInfo = pC->pKeyInfo;
    r.nField = (u16)pOp->p4.i;
    r.aMem = pIn3;
#ifdef SQLITE_DEBUG
    for(ii=0; ii<r.nField; ii++){
      assert( memIsValid(&r.aMem[ii]) );
      assert( (r.aMem[ii].flags & MEM_Zero)==0 || r.aMem[ii].n==0 );
      if( ii ) REGISTER_TRACE(pOp->p3+ii, &r.aMem[ii]);
    }
#endif
    pIdxKey = &r;
    pFree = 0;
  }else{
    pFree = pIdxKey = sqlite3VdbeAllocUnpackedRecord(pC->pKeyInfo);


    if( pIdxKey==0 ) goto no_mem;
    assert( pIn3->flags & MEM_Blob );
    (void)ExpandBlob(pIn3);
    sqlite3VdbeRecordUnpack(pC->pKeyInfo, pIn3->n, pIn3->z, pIdxKey);
  }
  pIdxKey->default_rc = 0;
  takeJump = 0;
  if( pOp->opcode==OP_NoConflict ){
    /* For the OP_NoConflict opcode, take the jump if any of the
    ** input fields are NULL, since any key with a NULL will not
    ** conflict */
    for(ii=0; ii<pIdxKey->nField; ii++){
      if( pIdxKey->aMem[ii].flags & MEM_Null ){
        takeJump = 1;
        break;
      }
    }
  }
  rc = sqlite3BtreeMovetoUnpacked(pC->uc.pCursor, pIdxKey, 0, 0, &res);
  if( pFree ) sqlite3DbFree(db, pFree);
  if( rc!=SQLITE_OK ){
    goto abort_due_to_error;
  }
  pC->seekResult = res;
  alreadyExists = (res==0);
  pC->nullRow = 1-alreadyExists;
  pC->deferredMoveto = 0;

      }
      assert( memIsValid(pMem) );

      REGISTER_TRACE(pOp->p3, pMem);
      sqlite3VdbeMemIntegerify(pMem);
      assert( (pMem->flags & MEM_Int)!=0 );  /* mem(P3) holds an integer */
      if( pMem->u.i==MAX_ROWID || pC->useRandomRowid ){
        rc = SQLITE_FULL;   /* IMP: R-17817-00630 */
        goto abort_due_to_error;
      }
      if( v<pMem->u.i+1 ){
        v = pMem->u.i + 1;
      }
      pMem->u.i = v;
    }

** be a MEM_Int.
**
** If the OPFLAG_NCHANGE flag of P5 is set, then the row change count is
** incremented (otherwise not).  If the OPFLAG_LASTROWID flag of P5 is set,
** then rowid is stored for subsequent return by the
** sqlite3_last_insert_rowid() function (otherwise it is unmodified).
**
** If the OPFLAG_USESEEKRESULT flag of P5 is set, the implementation might
** run faster by avoiding an unnecessary seek on cursor P1.  However,
** the OPFLAG_USESEEKRESULT flag must only be set if there have been no prior

** seeks on the cursor or if the most recent seek used a key equal to P3.




**
** If the OPFLAG_ISUPDATE flag is set, then this opcode is part of an
** UPDATE operation.  Otherwise (if the flag is clear) then this opcode
** is part of an INSERT operation.  The difference is only important to
** the update hook.
**
** Parameter P4 may point to a Table structure, or may be NULL. If it is 

      nExtraDelete--;
    }
  }
#endif

  rc = sqlite3BtreeDelete(pC->uc.pCursor, pOp->p5);
  pC->cacheStatus = CACHE_STALE;
  pC->seekResult = 0;
  if( rc ) goto abort_due_to_error;

  /* Invoke the update-hook if required. */
  if( opflags & OPFLAG_NCHANGE ){
    p->nChange++;
    if( db->xUpdateCallback && HasRowid(pTab) ){
      db->xUpdateCallback(db->pUpdateArg, SQLITE_DELETE, zDb, pTab->zName,

  p->apCsr[pOp->p3]->cacheStatus = CACHE_STALE;
  break;
}

/* Opcode: RowData P1 P2 * * *
** Synopsis: r[P2]=data
**
** Write into register P2 the complete row content for the row at 
** which cursor P1 is currently pointing.
** There is no interpretation of the data.  
** It is just copied onto the P2 register exactly as 
** it is found in the database file.
**






** If cursor P1 is an index, then the content is the key of the row.


** If cursor P2 is a table, then the content extracted is the data.
**
** If the P1 cursor must be pointing to a valid row (not a NULL row)
** of a real table, not a pseudo-table.
*/

case OP_RowData: {
  VdbeCursor *pC;
  BtCursor *pCrsr;
  u32 n;

  pOut = &aMem[pOp->p2];
  memAboutToChange(p, pOut);


  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
  pC = p->apCsr[pOp->p1];
  assert( pC!=0 );
  assert( pC->eCurType==CURTYPE_BTREE );
  assert( isSorter(pC)==0 );


  assert( pC->nullRow==0 );
  assert( pC->uc.pCursor!=0 );
  pCrsr = pC->uc.pCursor;

  /* The OP_RowData opcodes always follow OP_NotExists or
  ** OP_SeekRowid or OP_Rewind/Op_Next with no intervening instructions
  ** that might invalidate the cursor.
  ** If this where not the case, on of the following assert()s
  ** would fail.  Should this ever change (because of changes in the code
  ** generator) then the fix would be to insert a call to
  ** sqlite3VdbeCursorMoveto().
  */

  }
  testcase( n==0 );
  if( sqlite3VdbeMemClearAndResize(pOut, MAX(n,32)) ){
    goto no_mem;
  }
  pOut->n = n;
  MemSetTypeFlag(pOut, MEM_Blob);

  rc = sqlite3BtreePayload(pCrsr, 0, n, pOut->z);



  if( rc ) goto abort_due_to_error;
  pOut->enc = SQLITE_UTF8;  /* In case the blob is ever cast to text */
  UPDATE_MAX_BLOBSIZE(pOut);
  REGISTER_TRACE(pOp->p2, pOut);
  break;
}

** If the table or index is empty and P2>0, then jump immediately to P2.
** If P2 is 0 or if the table or index is not empty, fall through
** to the following instruction.
**
** This opcode leaves the cursor configured to move in reverse order,
** from the end toward the beginning.  In other words, the cursor is
** configured to use Prev, not Next.
**
** If P3 is -1, then the cursor is positioned at the end of the btree
** for the purpose of appending a new entry onto the btree.  In that
** case P2 must be 0.  It is assumed that the cursor is used only for
** appending and so if the cursor is valid, then the cursor must already
** be pointing at the end of the btree and so no changes are made to
** the cursor.
*/
case OP_Last: {        /* jump */
  VdbeCursor *pC;
  BtCursor *pCrsr;
  int res;

  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
  pC = p->apCsr[pOp->p1];
  assert( pC!=0 );
  assert( pC->eCurType==CURTYPE_BTREE );
  pCrsr = pC->uc.pCursor;
  res = 0;
  assert( pCrsr!=0 );




  pC->seekResult = pOp->p3;
#ifdef SQLITE_DEBUG
  pC->seekOp = OP_Last;
#endif
  if( pOp->p3==0 || !sqlite3BtreeCursorIsValidNN(pCrsr) ){
    rc = sqlite3BtreeLast(pCrsr, &res);
    pC->nullRow = (u8)res;
    pC->deferredMoveto = 0;
    pC->cacheStatus = CACHE_STALE;
    if( rc ) goto abort_due_to_error;
    if( pOp->p2>0 ){
      VdbeBranchTaken(res!=0,2);
      if( res ) goto jump_to_p2;
    }
  }else{
    assert( pOp->p2==0 );
  }
  break;
}


/* Opcode: SorterSort P1 P2 * * *
**
** After all records have been inserted into the Sorter object
** identified by P1, invoke this opcode to actually do the sorting.
** Jump to P2 if there are no records to be sorted.
**
** This opcode is an alias for OP_Sort and OP_Rewind that is used
** for Sorter objects.
*/
/* Opcode: Sort P1 P2 * * *
**
** This opcode does exactly the same thing as OP_Rewind except that
** it increments an undocumented global variable used for testing.
**
** Sorting is accomplished by writing records into a sorting index,
** then rewinding that index and playing it back from beginning to

** number P5-1 in the prepared statement is incremented.
*/
/* Opcode: PrevIfOpen P1 P2 P3 P4 P5
**
** This opcode works just like Prev except that if cursor P1 is not
** open it behaves a no-op.
*/
/* Opcode: SorterNext P1 P2 * * P5
**
** This opcode works just like OP_Next except that P1 must be a
** sorter object for which the OP_SorterSort opcode has been
** invoked.  This opcode advances the cursor to the next sorted
** record, or jumps to P2 if there are no more sorted records.
*/
case OP_SorterNext: {  /* jump */
  VdbeCursor *pC;
  int res;

  pC = p->apCsr[pOp->p1];
  assert( isSorter(pC) );
  res = 0;

    goto jump_to_p2_and_check_for_interrupt;
  }else{
    pC->nullRow = 1;
  }
  goto check_for_interrupt;
}

/* Opcode: IdxInsert P1 P2 P3 P4 P5
** Synopsis: key=r[P2]
**
** Register P2 holds an SQL index key made using the
** MakeRecord instructions.  This opcode writes that key
** into the index P1.  Data for the entry is nil.
**
** If P4 is not zero, then it is the number of values in the unpacked
** key of reg(P2).  In that case, P3 is the index of the first register
** for the unpacked key.  The availability of the unpacked key can sometimes
** be an optimization.
**
** If P5 has the OPFLAG_APPEND bit set, that is a hint to the b-tree layer
** that this insert is likely to be an append.
**
** If P5 has the OPFLAG_NCHANGE bit set, then the change counter is
** incremented by this instruction.  If the OPFLAG_NCHANGE bit is clear,
** then the change counter is unchanged.
**
** If the OPFLAG_USESEEKRESULT flag of P5 is set, the implementation might
** run faster by avoiding an unnecessary seek on cursor P1.  However,
** the OPFLAG_USESEEKRESULT flag must only be set if there have been no prior
** seeks on the cursor or if the most recent seek used a key equivalent
** to P2. 
**
** This instruction only works for indices.  The equivalent instruction
** for tables is OP_Insert.
*/
/* Opcode: SorterInsert P1 P2 * * *
** Synopsis: key=r[P2]
**
** Register P2 holds an SQL index key made using the
** MakeRecord instructions.  This opcode writes that key
** into the sorter P1.  Data for the entry is nil.
*/
case OP_SorterInsert:       /* in2 */
case OP_IdxInsert: {        /* in2 */
  VdbeCursor *pC;
  BtreePayload x;

  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
  pC = p->apCsr[pOp->p1];

  rc = ExpandBlob(pIn2);
  if( rc ) goto abort_due_to_error;
  if( pOp->opcode==OP_SorterInsert ){
    rc = sqlite3VdbeSorterWrite(pC, pIn2);
  }else{
    x.nKey = pIn2->n;
    x.pKey = pIn2->z;
    x.aMem = aMem + pOp->p3;
    x.nMem = (u16)pOp->p4.i;
    rc = sqlite3BtreeInsert(pC->uc.pCursor, &x,
         (pOp->p5 & OPFLAG_APPEND)!=0, 
        ((pOp->p5 & OPFLAG_USESEEKRESULT) ? pC->seekResult : 0)
        );
    assert( pC->deferredMoveto==0 );
    pC->cacheStatus = CACHE_STALE;
  }
  if( rc) goto abort_due_to_error;
  break;

  if( rc ) goto abort_due_to_error;
  if( res==0 ){
    rc = sqlite3BtreeDelete(pCrsr, BTREE_AUXDELETE);
    if( rc ) goto abort_due_to_error;
  }
  assert( pC->deferredMoveto==0 );
  pC->cacheStatus = CACHE_STALE;
  pC->seekResult = 0;
  break;
}

/* Opcode: Seek P1 * P3 P4 *
** Synopsis: Move P3 to P1.rowid
**
** P1 is an open index cursor and P3 is a cursor on the corresponding

  }
#endif

  iDb = pOp->p1;
  assert( iDb>=0 && iDb<db->nDb );
  assert( DbHasProperty(db, iDb, DB_SchemaLoaded) );
  /* Used to be a conditional */ {
    zMaster = MASTER_NAME;
    initData.db = db;
    initData.iDb = pOp->p1;
    initData.pzErrMsg = &p->zErrMsg;
    zSql = sqlite3MPrintf(db,
       "SELECT name, rootpage, sql FROM '%q'.%s WHERE %s ORDER BY rowid",
       db->aDb[iDb].zDbSName, zMaster, pOp->p4.z);
    if( zSql==0 ){

**
** if r[P1] is zero or negative, that means there is no LIMIT
** and r[P2] is set to -1. 
**
** Otherwise, r[P2] is set to the sum of r[P1] and r[P3].
*/
case OP_OffsetLimit: {    /* in1, out2, in3 */
  i64 x;
  pIn1 = &aMem[pOp->p1];
  pIn3 = &aMem[pOp->p3];
  pOut = out2Prerelease(p, pOp);
  assert( pIn1->flags & MEM_Int );
  assert( pIn3->flags & MEM_Int );
  x = pIn1->u.i;
  if( x<=0 || sqlite3AddInt64(&x, pIn3->u.i>0?pIn3->u.i:0) ){
    /* If the LIMIT is less than or equal to zero, loop forever.  This
    ** is documented.  But also, if the LIMIT+OFFSET exceeds 2^63 then
    ** also loop forever.  This is undocumented.  In fact, one could argue
    ** that the loop should terminate.  But assuming 1 billion iterations
    ** per second (far exceeding the capabilities of any current hardware)
    ** it would take nearly 300 years to actually reach the limit.  So
    ** looping forever is a reasonable approximation. */
    pOut->u.i = -1;
  }else{
    pOut->u.i = x;
  }
  break;
}

/* Opcode: IfNotZero P1 P2 * * *
** Synopsis: if r[P1]!=0 then r[P1]--, goto P2
**
** Register P1 must contain an integer.  If the content of register P1 is
** initially greater than zero, then decrement the value in register P1.
** If it is non-zero (negative or positive) and then also jump to P2.  
** If register P1 is initially zero, leave it unchanged and fall through.

*/
case OP_IfNotZero: {        /* jump, in1 */
  pIn1 = &aMem[pOp->p1];
  assert( pIn1->flags&MEM_Int );
  VdbeBranchTaken(pIn1->u.i<0, 2);
  if( pIn1->u.i ){
     if( pIn1->u.i>0 ) pIn1->u.i--;
     goto jump_to_p2;
  }
  break;
}

/* Opcode: DecrJumpZero P1 P2 * * *
** Synopsis: if (--r[P1])==0 goto P2
**
** Register P1 must hold an integer.  Decrement the value in P1
** and jump to P2 if the new value is exactly zero.
*/
case OP_DecrJumpZero: {      /* jump, in1 */
  pIn1 = &aMem[pOp->p1];
  assert( pIn1->flags&MEM_Int );
  if( pIn1->u.i>SMALLEST_INT64 ) pIn1->u.i--;
  VdbeBranchTaken(pIn1->u.i==0, 2);
  if( pIn1->u.i==0 ) goto jump_to_p2;
  break;
}


/* Opcode: AggStep0 * P2 P3 P4 P5

 
      if( eOld==PAGER_JOURNALMODE_WAL ){
        /* If leaving WAL mode, close the log file. If successful, the call
        ** to PagerCloseWal() checkpoints and deletes the write-ahead-log 
        ** file. An EXCLUSIVE lock may still be held on the database file 
        ** after a successful return. 
        */
        rc = sqlite3PagerCloseWal(pPager, db);
        if( rc==SQLITE_OK ){
          sqlite3PagerSetJournalMode(pPager, eNew);
        }
      }else if( eOld==PAGER_JOURNALMODE_MEMORY ){
        /* Cannot transition directly from MEMORY to WAL.  Use mode OFF
        ** as an intermediate */
        sqlite3PagerSetJournalMode(pPager, PAGER_JOURNALMODE_OFF);

        {OP_TableLock,      0, 0, 0},  /* 0: Acquire a read or write lock */
        {OP_OpenRead,       0, 0, 0},  /* 1: Open a cursor */
        {OP_Variable,       1, 1, 0},  /* 2: Move ?1 into reg[1] */
        {OP_NotExists,      0, 7, 1},  /* 3: Seek the cursor */
        {OP_Column,         0, 0, 1},  /* 4  */
        {OP_ResultRow,      1, 0, 0},  /* 5  */
        {OP_Goto,           0, 2, 0},  /* 6  */

        {OP_Halt,           0, 0, 0},  /* 7  */
      };
      Vdbe *v = (Vdbe *)pBlob->pStmt;
      int iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
      VdbeOp *aOp;

      sqlite3VdbeAddOp4Int(v, OP_Transaction, iDb, flags, 
                           pTab->pSchema->schema_cookie,

  return rc;
}

/*
** Read data from a blob handle.
*/
SQLITE_API int sqlite3_blob_read(sqlite3_blob *pBlob, void *z, int n, int iOffset){
  return blobReadWrite(pBlob, z, n, iOffset, sqlite3BtreePayloadChecked);
}

/*
** Write data to a blob handle.
*/
SQLITE_API int sqlite3_blob_write(sqlite3_blob *pBlob, const void *z, int n, int iOffset){
  return blobReadWrite(pBlob, (void *)z, n, iOffset, sqlite3BtreePutData);

  ** to exceed the maximum merge count */
#if SQLITE_MAX_WORKER_THREADS>=SORTER_MAX_MERGE_COUNT
  if( nWorker>=SORTER_MAX_MERGE_COUNT ){
    nWorker = SORTER_MAX_MERGE_COUNT-1;
  }
#endif

  assert( pCsr->pKeyInfo && pCsr->pBtx==0 );
  assert( pCsr->eCurType==CURTYPE_SORTER );
  szKeyInfo = sizeof(KeyInfo) + (pCsr->pKeyInfo->nField-1)*sizeof(CollSeq*);
  sz = sizeof(VdbeSorter) + nWorker * sizeof(SortSubtask);

  pSorter = (VdbeSorter*)sqlite3DbMallocZero(db, sz + szKeyInfo);
  pCsr->uc.pSorter = pSorter;
  if( pSorter==0 ){

/*
** If it has not already been allocated, allocate the UnpackedRecord 
** structure at pTask->pUnpacked. Return SQLITE_OK if successful (or 
** if no allocation was required), or SQLITE_NOMEM otherwise.
*/
static int vdbeSortAllocUnpacked(SortSubtask *pTask){
  if( pTask->pUnpacked==0 ){

    pTask->pUnpacked = sqlite3VdbeAllocUnpackedRecord(pTask->pSorter->pKeyInfo);



    if( pTask->pUnpacked==0 ) return SQLITE_NOMEM_BKPT;
    pTask->pUnpacked->nField = pTask->pSorter->pKeyInfo->nField;
    pTask->pUnpacked->errCode = 0;
  }
  return SQLITE_OK;
}

  void *pKey; int nKey;           /* Sorter key to compare pVal with */

  assert( pCsr->eCurType==CURTYPE_SORTER );
  pSorter = pCsr->uc.pSorter;
  r2 = pSorter->pUnpacked;
  pKeyInfo = pCsr->pKeyInfo;
  if( r2==0 ){

    r2 = pSorter->pUnpacked = sqlite3VdbeAllocUnpackedRecord(pKeyInfo);

    if( r2==0 ) return SQLITE_NOMEM_BKPT;
    r2->nField = nKeyCol;
  }
  assert( r2->nField==nKeyCol );

  pKey = vdbeSorterRowkey(pSorter, &nKey);
  sqlite3VdbeRecordUnpack(pKeyInfo, nKey, pKey, r2);

    ** sqlite3ExprDelete() specifically skips the recursive delete of
    ** pLeft on TK_SELECT_COLUMN nodes.  But pRight is followed, so pVector
    ** can be attached to pRight to cause this node to take ownership of
    ** pVector.  Typically there will be multiple TK_SELECT_COLUMN nodes
    ** with the same pLeft pointer to the pVector, but only one of them
    ** will own the pVector.
    */
    pRet = sqlite3PExpr(pParse, TK_SELECT_COLUMN, 0, 0);
    if( pRet ){
      pRet->iColumn = iField;
      pRet->pLeft = pVector;
    }
    assert( pRet==0 || pRet->iTable==0 );
  }else{
    if( pVector->op==TK_VECTOR ) pVector = pVector->x.pList->a[iField].pExpr;

  int nLeft = sqlite3ExprVectorSize(pLeft);
  int i;
  int regLeft = 0;
  int regRight = 0;
  u8 opx = op;
  int addrDone = sqlite3VdbeMakeLabel(v);

  if( nLeft!=sqlite3ExprVectorSize(pRight) ){
    sqlite3ErrorMsg(pParse, "row value misused");
    return;
  }
  assert( pExpr->op==TK_EQ || pExpr->op==TK_NE 
       || pExpr->op==TK_IS || pExpr->op==TK_ISNOT 
       || pExpr->op==TK_LT || pExpr->op==TK_GT 
       || pExpr->op==TK_LE || pExpr->op==TK_GE 
  );
  assert( pExpr->op==op || (pExpr->op==TK_IS && op==TK_EQ)
            || (pExpr->op==TK_ISNOT && op==TK_NE) );

** Expr node.  Or, if an OOM error occurs, set pParse->db->mallocFailed,
** free the subtrees and return NULL.
*/
SQLITE_PRIVATE Expr *sqlite3PExpr(
  Parse *pParse,          /* Parsing context */
  int op,                 /* Expression opcode */
  Expr *pLeft,            /* Left operand */
  Expr *pRight            /* Right operand */

){
  Expr *p;
  if( op==TK_AND && pParse->nErr==0 ){
    /* Take advantage of short-circuit false optimization for AND */
    p = sqlite3ExprAnd(pParse->db, pLeft, pRight);
  }else{
    p = sqlite3DbMallocRawNN(pParse->db, sizeof(Expr));
    if( p ){
      memset(p, 0, sizeof(Expr));
      p->op = op & TKFLG_MASK;
      p->iAgg = -1;
    }
    sqlite3ExprAttachSubtrees(pParse->db, p, pLeft, pRight);
  }
  if( p ) {
    sqlite3ExprCheckHeight(pParse, p->nHeight);
  }
  return p;
}

** Assign a variable number to an expression that encodes a wildcard
** in the original SQL statement.  
**
** Wildcards consisting of a single "?" are assigned the next sequential
** variable number.
**
** Wildcards of the form "?nnn" are assigned the number "nnn".  We make
** sure "nnn" is not too big to avoid a denial of service attack when
** the SQL statement comes from an external source.
**
** Wildcards of the form ":aaa", "@aaa", or "$aaa" are assigned the same number
** as the previous instance of the same wildcard.  Or if this is the first
** instance of the wildcard, the next sequential variable number is
** assigned.
*/
SQLITE_PRIVATE void sqlite3ExprAssignVarNumber(Parse *pParse, Expr *pExpr, u32 n){
  sqlite3 *db = pParse->db;
  const char *z;
  ynVar x;

  if( pExpr==0 ) return;
  assert( !ExprHasProperty(pExpr, EP_IntValue|EP_Reduced|EP_TokenOnly) );
  z = pExpr->u.zToken;
  assert( z!=0 );
  assert( z[0]!=0 );
  assert( n==sqlite3Strlen30(z) );
  if( z[1]==0 ){
    /* Wildcard of the form "?".  Assign the next variable number */
    assert( z[0]=='?' );
    x = (ynVar)(++pParse->nVar);
  }else{
    int doAdd = 0;
    if( z[0]=='?' ){
      /* Wildcard of the form "?nnn".  Convert "nnn" to an integer and
      ** use it as the variable number */
      i64 i;
      int bOk = 0==sqlite3Atoi64(&z[1], &i, n-1, SQLITE_UTF8);
      x = (ynVar)i;
      testcase( i==0 );
      testcase( i==1 );
      testcase( i==db->aLimit[SQLITE_LIMIT_VARIABLE_NUMBER]-1 );
      testcase( i==db->aLimit[SQLITE_LIMIT_VARIABLE_NUMBER] );
      if( bOk==0 || i<1 || i>db->aLimit[SQLITE_LIMIT_VARIABLE_NUMBER] ){
        sqlite3ErrorMsg(pParse, "variable number must be between ?1 and ?%d",
            db->aLimit[SQLITE_LIMIT_VARIABLE_NUMBER]);
        return;
      }
      if( x>pParse->nVar ){
        pParse->nVar = (int)x;
        doAdd = 1;
      }else if( sqlite3VListNumToName(pParse->pVList, x)==0 ){
        doAdd = 1;
      }
    }else{
      /* Wildcards like ":aaa", "$aaa" or "@aaa".  Reuse the same variable
      ** number as the prior appearance of the same name, or if the name
      ** has never appeared before, reuse the same variable number
      */



      x = (ynVar)sqlite3VListNameToNum(pParse->pVList, z, n);



      if( x==0 ){


        x = (ynVar)(++pParse->nVar);
        doAdd = 1;




      }



    }
    if( doAdd ){
      pParse->pVList = sqlite3VListAdd(db, pParse->pVList, z, n, x);
    }
  }
  pExpr->iColumn = x;
  if( x>db->aLimit[SQLITE_LIMIT_VARIABLE_NUMBER] ){
    sqlite3ErrorMsg(pParse, "too many SQL variables");
  }
}

/*
** Recursively delete an expression tree.
*/

    pNewItem->pIBIndex = pOldItem->pIBIndex;
    if( pNewItem->fg.isTabFunc ){
      pNewItem->u1.pFuncArg = 
          sqlite3ExprListDup(db, pOldItem->u1.pFuncArg, flags);
    }
    pTab = pNewItem->pTab = pOldItem->pTab;
    if( pTab ){
      pTab->nTabRef++;
    }
    pNewItem->pSelect = sqlite3SelectDup(db, pOldItem->pSelect, flags);
    pNewItem->pOn = sqlite3ExprDup(db, pOldItem->pOn, flags);
    pNewItem->pUsing = sqlite3IdListDup(db, pOldItem->pUsing);
    pNewItem->colUsed = pOldItem->colUsed;
  }
  return pNew;

**   "sub-select returns N columns - expected M"
*/   
SQLITE_PRIVATE void sqlite3SubselectError(Parse *pParse, int nActual, int nExpect){
  const char *zFmt = "sub-select returns %d columns - expected %d";
  sqlite3ErrorMsg(pParse, zFmt, nActual, nExpect);
}
#endif

/*
** Expression pExpr is a vector that has been used in a context where
** it is not permitted. If pExpr is a sub-select vector, this routine 
** loads the Parse object with a message of the form:
**
**   "sub-select returns N columns - expected 1"
**
** Or, if it is a regular scalar vector:
**
**   "row value misused"
*/   
SQLITE_PRIVATE void sqlite3VectorErrorMsg(Parse *pParse, Expr *pExpr){
#ifndef SQLITE_OMIT_SUBQUERY
  if( pExpr->flags & EP_xIsSelect ){
    sqlite3SubselectError(pParse, pExpr->x.pSelect->pEList->nExpr, 1);
  }else
#endif
  {
    sqlite3ErrorMsg(pParse, "row value misused");
  }
}

/*
** Generate code for scalar subqueries used as a subquery expression, EXISTS,
** or IN operators.  Examples:
**
**     (SELECT a FROM b)          -- subquery
**     EXISTS (SELECT a FROM b)   -- EXISTS subquery

              sqlite3VdbeAddOp2(v, OP_MustBeInt, r3,
                                sqlite3VdbeCurrentAddr(v)+2);
              VdbeCoverage(v);
              sqlite3VdbeAddOp3(v, OP_Insert, pExpr->iTable, r2, r3);
            }else{
              sqlite3VdbeAddOp4(v, OP_MakeRecord, r3, 1, r2, &affinity, 1);
              sqlite3ExprCacheAffinityChange(pParse, r3, 1);
              sqlite3VdbeAddOp4Int(v, OP_IdxInsert, pExpr->iTable, r2, r3, 1);
            }
          }
        }
        sqlite3ReleaseTempReg(pParse, r1);
        sqlite3ReleaseTempReg(pParse, r2);
      }
      if( pKeyInfo ){

  int nVector = sqlite3ExprVectorSize(pIn->pLeft);
  if( (pIn->flags & EP_xIsSelect) ){
    if( nVector!=pIn->x.pSelect->pEList->nExpr ){
      sqlite3SubselectError(pParse, pIn->x.pSelect->pEList->nExpr, nVector);
      return 1;
    }
  }else if( nVector!=1 ){



    sqlite3VectorErrorMsg(pParse, pIn->pLeft);

    return 1;
  }
  return 0;
}
#endif

#ifndef SQLITE_OMIT_SUBQUERY

    sqlite3VdbeAddOp2(v, OP_Integer, i, iMem);
  }else{
    int c;
    i64 value;
    const char *z = pExpr->u.zToken;
    assert( z!=0 );
    c = sqlite3DecOrHexToI64(z, &value);
    if( c==1 || (c==2 && !negFlag) || (negFlag && value==SMALLEST_INT64)){



#ifdef SQLITE_OMIT_FLOATING_POINT
      sqlite3ErrorMsg(pParse, "oversized integer: %s%s", negFlag ? "-" : "", z);
#else
#ifndef SQLITE_OMIT_HEX_INTEGER
      if( sqlite3_strnicmp(z,"0x",2)==0 ){
        sqlite3ErrorMsg(pParse, "hex literal too big: %s%s", negFlag?"-":"",z);
      }else
#endif
      {
        codeReal(v, z, negFlag, iMem);
      }
#endif
    }else{
      if( negFlag ){ value = c==2 ? SMALLEST_INT64 : -value; }
      sqlite3VdbeAddOp4Dup8(v, OP_Int64, 0, iMem, 0, (u8*)&value, P4_INT64);
    }
  }
}

/*
** Erase column-cache entry number i
*/

#endif
    case TK_VARIABLE: {
      assert( !ExprHasProperty(pExpr, EP_IntValue) );
      assert( pExpr->u.zToken!=0 );
      assert( pExpr->u.zToken[0]!=0 );
      sqlite3VdbeAddOp2(v, OP_Variable, pExpr->iColumn, target);
      if( pExpr->u.zToken[1]!=0 ){
        const char *z = sqlite3VListNumToName(pParse->pVList, pExpr->iColumn);
        assert( pExpr->u.zToken[0]=='?' || strcmp(pExpr->u.zToken, z)==0 );
        pParse->pVList[0] = 0; /* Indicate VList may no longer be enlarged */
        sqlite3VdbeAppendP4(v, (char*)z, P4_STATIC);
      }
      return target;
    }
    case TK_REGISTER: {
      return pExpr->iTable;
    }
#ifndef SQLITE_OMIT_CAST

  assert( pList!=0 );
  assert( target>0 );
  assert( pParse->pVdbe!=0 );  /* Never gets this far otherwise */
  n = pList->nExpr;
  if( !ConstFactorOk(pParse) ) flags &= ~SQLITE_ECEL_FACTOR;
  for(pItem=pList->a, i=0; i<n; i++, pItem++){
    Expr *pExpr = pItem->pExpr;
    if( (flags & SQLITE_ECEL_REF)!=0 && (j = pItem->u.x.iOrderByCol)>0 ){
      if( flags & SQLITE_ECEL_OMITREF ){
        i--;
        n--;
      }else{
        sqlite3VdbeAddOp2(v, copyOp, j+srcReg-1, target+i);
      }
    }else if( (flags & SQLITE_ECEL_FACTOR)!=0 && sqlite3ExprIsConstant(pExpr) ){
      sqlite3ExprCodeAtInit(pParse, pExpr, target+i, 0);
    }else{
      int inReg = sqlite3ExprCodeTarget(pParse, pExpr, target+i);
      if( inReg!=target+i ){
        VdbeOp *pOp;
        if( copyOp==OP_Copy

  compRight.op = TK_LE;
  compRight.pLeft = &exprX;
  compRight.pRight = pExpr->x.pList->a[1].pExpr;
  exprToRegister(&exprX, exprCodeVector(pParse, &exprX, &regFree1));
  if( xJump ){
    xJump(pParse, &exprAnd, dest, jumpIfNull);
  }else{
    /* Mark the expression is being from the ON or USING clause of a join
    ** so that the sqlite3ExprCodeTarget() routine will not attempt to move
    ** it into the Parse.pConstExpr list.  We should use a new bit for this,
    ** for clarity, but we are out of bits in the Expr.flags field so we
    ** have to reuse the EP_FromJoin bit.  Bummer. */
    exprX.flags |= EP_FromJoin;
    sqlite3ExprCodeTarget(pParse, &exprAnd, dest);
  }
  sqlite3ReleaseTempReg(pParse, regFree1);

  /* Ensure adequate test coverage */
  testcase( xJump==sqlite3ExprIfTrue  && jumpIfNull==0 && regFree1==0 );

  }
  if( pE2->op==TK_OR
   && (sqlite3ExprImpliesExpr(pE1, pE2->pLeft, iTab)
             || sqlite3ExprImpliesExpr(pE1, pE2->pRight, iTab) )
  ){
    return 1;
  }
  if( pE2->op==TK_NOTNULL && pE1->op!=TK_ISNULL && pE1->op!=TK_IS ){
    Expr *pX = sqlite3ExprSkipCollate(pE1->pLeft);
    testcase( pX!=pE1->pLeft );

    if( sqlite3ExprCompare(pX, pE2->pLeft, iTab)==0 ) return 1;
  }
  return 0;
}

/*
** An instance of the following structure is used by the tree walker
** to determine if an expression can be evaluated by reference to the

    /* If foreign-key support is enabled, rewrite the CREATE TABLE 
    ** statements corresponding to all child tables of foreign key constraints
    ** for which the renamed table is the parent table.  */
    if( (zWhere=whereForeignKeys(pParse, pTab))!=0 ){
      sqlite3NestedParse(pParse, 
          "UPDATE \"%w\".%s SET "
              "sql = sqlite_rename_parent(sql, %Q, %Q) "
              "WHERE %s;", zDb, MASTER_NAME, zTabName, zName, zWhere);
      sqlite3DbFree(db, zWhere);
    }
  }
#endif

  /* Modify the sqlite_master table to use the new table name. */
  sqlite3NestedParse(pParse,

          "name = CASE "
            "WHEN type='table' THEN %Q "
            "WHEN name LIKE 'sqlite_autoindex%%' AND type='index' THEN "
             "'sqlite_autoindex_' || %Q || substr(name,%d+18) "
            "ELSE name END "
      "WHERE tbl_name=%Q COLLATE nocase AND "
          "(type='table' OR type='index' OR type='trigger');", 
      zDb, MASTER_NAME, zName, zName, zName, 
#ifndef SQLITE_OMIT_TRIGGER
      zName,
#endif
      zName, nTabName, zTabName
  );

#ifndef SQLITE_OMIT_AUTOINCREMENT

      *zEnd-- = '\0';
    }
    db->flags |= SQLITE_PreferBuiltin;
    sqlite3NestedParse(pParse, 
        "UPDATE \"%w\".%s SET "
          "sql = substr(sql,1,%d) || ', ' || %Q || substr(sql,%d) "
        "WHERE type = 'table' AND name = %Q", 
      zDb, MASTER_NAME, pNew->addColOffset, zCol, pNew->addColOffset+1,
      zTab
    );
    sqlite3DbFree(db, zCol);
    db->flags = savedDbFlags;
  }

  /* Make sure the schema version is at least 3.  But do not upgrade

  ** prefix, we insure that the name will not collide with an existing
  ** table because user table are not allowed to have the "sqlite_"
  ** prefix on their name.
  */
  pNew = (Table*)sqlite3DbMallocZero(db, sizeof(Table));
  if( !pNew ) goto exit_begin_add_column;
  pParse->pNewTable = pNew;
  pNew->nTabRef = 1;
  pNew->nCol = pTab->nCol;
  assert( pNew->nCol>0 );
  nAlloc = (((pNew->nCol-1)/8)*8)+8;
  assert( nAlloc>=pNew->nCol && nAlloc%8==0 && nAlloc-pNew->nCol<8 );
  pNew->aCol = (Column*)sqlite3DbMallocZero(db, sizeof(Column)*nAlloc);
  pNew->zName = sqlite3MPrintf(db, "sqlite_altertab_%s", pTab->zName);
  if( !pNew->aCol || !pNew->zName ){
    assert( db->mallocFailed );
    goto exit_begin_add_column;
  }
  memcpy(pNew->aCol, pTab->aCol, sizeof(Column)*pNew->nCol);
  for(i=0; i<pNew->nCol; i++){
    Column *pCol = &pNew->aCol[i];
    pCol->zName = sqlite3DbStrDup(db, pCol->zName);
    pCol->zColl = 0;
    pCol->pDflt = 0;
  }
  pNew->pSchema = db->aDb[iDb].pSchema;
  pNew->addColOffset = pTab->addColOffset;
  pNew->nTabRef = 1;

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

    ** a buffer overread.  */
    pSample->n = sqlite3_column_bytes(pStmt, 4);
    pSample->p = sqlite3DbMallocZero(db, pSample->n + 2);
    if( pSample->p==0 ){
      sqlite3_finalize(pStmt);
      return SQLITE_NOMEM_BKPT;
    }
    if( pSample->n ){
      memcpy(pSample->p, sqlite3_column_blob(pStmt, 4), pSample->n);
    }
    pIdx->nSample++;
  }
  rc = sqlite3_finalize(pStmt);
  if( rc==SQLITE_OK ) initAvgEq(pPrevIdx);
  return rc;
}

#ifndef SQLITE_OMIT_SHARED_CACHE
/*
** The TableLock structure is only used by the sqlite3TableLock() and
** codeTableLocks() functions.
*/
struct TableLock {
  int iDb;               /* The database containing the table to be locked */
  int iTab;              /* The root page of the table to be locked */
  u8 isWriteLock;        /* True for write lock.  False for a read lock */
  const char *zLockName; /* Name of the table */
};

/*
** Record the fact that we want to lock a table at run-time.  
**
** The table to be locked has root page iTab and is found in database iDb.
** A read or a write lock can be taken depending on isWritelock.

){
  Parse *pToplevel = sqlite3ParseToplevel(pParse);
  int i;
  int nBytes;
  TableLock *p;
  assert( iDb>=0 );

  if( iDb==1 ) return;
  if( !sqlite3BtreeSharable(pParse->db->aDb[iDb].pBt) ) return;
  for(i=0; i<pToplevel->nTableLock; i++){
    p = &pToplevel->aTableLock[i];
    if( p->iDb==iDb && p->iTab==iTab ){
      p->isWriteLock = (p->isWriteLock || isWriteLock);
      return;
    }
  }

  nBytes = sizeof(TableLock) * (pToplevel->nTableLock+1);
  pToplevel->aTableLock =
      sqlite3DbReallocOrFree(pToplevel->db, pToplevel->aTableLock, nBytes);
  if( pToplevel->aTableLock ){
    p = &pToplevel->aTableLock[pToplevel->nTableLock++];
    p->iDb = iDb;
    p->iTab = iTab;
    p->isWriteLock = isWriteLock;
    p->zLockName = zName;
  }else{
    pToplevel->nTableLock = 0;
    sqlite3OomFault(pToplevel->db);
  }
}

/*

  pVdbe = sqlite3GetVdbe(pParse);
  assert( pVdbe!=0 ); /* sqlite3GetVdbe cannot fail: VDBE already allocated */

  for(i=0; i<pParse->nTableLock; i++){
    TableLock *p = &pParse->aTableLock[i];
    int p1 = p->iDb;
    sqlite3VdbeAddOp4(pVdbe, OP_TableLock, p1, p->iTab, p->isWriteLock,
                      p->zLockName, P4_STATIC);
  }
}
#else
  #define codeTableLocks(x)
#endif

/*

#if SQLITE_USER_AUTHENTICATION
  /* Only the admin user is allowed to know that the sqlite_user table
  ** exists */
  if( db->auth.authLevel<UAUTH_Admin && sqlite3UserAuthTable(zName)!=0 ){
    return 0;
  }
#endif
  while(1){
    for(i=OMIT_TEMPDB; i<db->nDb; i++){
      int j = (i<2) ? i^1 : i;   /* Search TEMP before MAIN */
      if( zDatabase==0 || sqlite3StrICmp(zDatabase, db->aDb[j].zDbSName)==0 ){
        assert( sqlite3SchemaMutexHeld(db, j, 0) );
        p = sqlite3HashFind(&db->aDb[j].pSchema->tblHash, zName);
        if( p ) return p;
      }
    }
    /* Not found.  If the name we were looking for was temp.sqlite_master
    ** then change the name to sqlite_temp_master and try again. */
    if( sqlite3StrICmp(zName, MASTER_NAME)!=0 ) break;
    if( sqlite3_stricmp(zDatabase, db->aDb[1].zDbSName)!=0 ) break;
    zName = TEMP_MASTER_NAME;
  }
  return 0;
}

/*
** Locate the in-memory structure that describes a particular database
** table given the name of that table and (optionally) the name of the
** database containing the table.  Return NULL if not found.  Also leave an
** error message in pParse->zErrMsg.

    const char *zMsg = flags & LOCATE_VIEW ? "no such view" : "no such table";
#ifndef SQLITE_OMIT_VIRTUALTABLE
    if( sqlite3FindDbName(pParse->db, zDbase)<1 ){
      /* If zName is the not the name of a table in the schema created using
      ** CREATE, then check to see if it is the name of an virtual table that
      ** can be an eponymous virtual table. */
      Module *pMod = (Module*)sqlite3HashFind(&pParse->db->aModule, zName);
      if( pMod==0 && sqlite3_strnicmp(zName, "pragma_", 7)==0 ){
        pMod = sqlite3PragmaVtabRegister(pParse->db, zName);
      }
      if( pMod && sqlite3VtabEponymousTableInit(pParse, pMod) ){
        return pMod->pEpoTab;
      }
    }
#endif
    if( (flags & LOCATE_NOERR)==0 ){
      if( zDbase ){

  /* Verify that no lookaside memory was used by schema tables */
  assert( nLookaside==0 || nLookaside==db->lookaside.nOut );
}
SQLITE_PRIVATE void sqlite3DeleteTable(sqlite3 *db, Table *pTable){
  /* Do not delete the table until the reference count reaches zero. */
  if( !pTable ) return;
  if( ((!db || db->pnBytesFreed==0) && (--pTable->nTabRef)>0) ) return;
  deleteTable(db, pTable);
}


/*
** Unlink the given table from the hash tables and the delete the
** table structure with all its indices and foreign keys.

/*
** Open the sqlite_master table stored in database number iDb for
** writing. The table is opened using cursor 0.
*/
SQLITE_PRIVATE void sqlite3OpenMasterTable(Parse *p, int iDb){
  Vdbe *v = sqlite3GetVdbe(p);
  sqlite3TableLock(p, iDb, MASTER_ROOT, 1, MASTER_NAME);
  sqlite3VdbeAddOp4Int(v, OP_OpenWrite, 0, MASTER_ROOT, iDb, 5);
  if( p->nTab==0 ){
    p->nTab = 1;
  }
}

/*
** Parameter zName points to a nul-terminated buffer containing the name
** of a database ("main", "temp" or the name of an attached db). This
** function returns the index of the named database in db->aDb[], or
** -1 if the named db cannot be found.
*/
SQLITE_PRIVATE int sqlite3FindDbName(sqlite3 *db, const char *zName){
  int i = -1;         /* Database number */
  if( zName ){
    Db *pDb;
    for(i=(db->nDb-1), pDb=&db->aDb[i]; i>=0; i--, pDb--){
      if( 0==sqlite3_stricmp(pDb->zDbSName, zName) ) break;
      /* "main" is always an acceptable alias for the primary database
      ** even if it has been renamed using SQLITE_DBCONFIG_MAINDBNAME. */
      if( i==0 && 0==sqlite3_stricmp("main", zName) ) break;
    }
  }
  return i;
}

/*
** The token *pName contains the name of a database (either "main" or

    pParse->rc = SQLITE_NOMEM_BKPT;
    pParse->nErr++;
    goto begin_table_error;
  }
  pTable->zName = zName;
  pTable->iPKey = -1;
  pTable->pSchema = db->aDb[iDb].pSchema;
  pTable->nTabRef = 1;
  pTable->nRowLogEst = 200; assert( 200==sqlite3LogEst(1048576) );
  assert( pParse->pNewTable==0 );
  pParse->pNewTable = pTable;

  /* If this is the magic sqlite_sequence table used by autoincrement,
  ** then record a pointer to this table in the main database structure
  ** so that INSERT can find the table easily.

    ** SQLITE_MASTER table.  We just need to update that slot with all
    ** the information we've collected.
    */
    sqlite3NestedParse(pParse,
      "UPDATE %Q.%s "
         "SET type='%s', name=%Q, tbl_name=%Q, rootpage=#%d, sql=%Q "
       "WHERE rowid=#%d",
      db->aDb[iDb].zDbSName, MASTER_NAME,
      zType,
      p->zName,
      p->zName,
      pParse->regRoot,
      zStmt,
      pParse->regRowid
    );

  **
  ** The "#NNN" in the SQL is a special constant that means whatever value
  ** is in register NNN.  See grammar rules associated with the TK_REGISTER
  ** token for additional information.
  */
  sqlite3NestedParse(pParse, 
     "UPDATE %Q.%s SET rootpage=%d WHERE #%d AND rootpage=#%d",
     pParse->db->aDb[iDb].zDbSName, MASTER_NAME, iTable, r1, r1);
#endif
  sqlite3ReleaseTempReg(pParse, r1);
}

/*
** Write VDBE code to erase table pTab and all associated indices on disk.
** Code to update the sqlite_master tables and internal schema definitions

  ** every row that refers to a table of the same name as the one being
  ** dropped. Triggers are handled separately because a trigger can be
  ** created in the temp database that refers to a table in another
  ** database.
  */
  sqlite3NestedParse(pParse, 
      "DELETE FROM %Q.%s WHERE tbl_name=%Q and type!='trigger'",
      pDb->zDbSName, MASTER_NAME, pTab->zName);
  if( !isView && !IsVirtual(pTab) ){
    destroyTable(pParse, pTab);
  }

  /* Remove the table entry from SQLite's internal schema and modify
  ** the schema cookie.
  */

                         pIndex->nKeyCol); VdbeCoverage(v);
    sqlite3UniqueConstraint(pParse, OE_Abort, pIndex);
  }else{
    addr2 = sqlite3VdbeCurrentAddr(v);
  }
  sqlite3VdbeAddOp3(v, OP_SorterData, iSorter, regRecord, iIdx);
  sqlite3VdbeAddOp3(v, OP_Last, iIdx, 0, -1);
  sqlite3VdbeAddOp2(v, OP_IdxInsert, iIdx, regRecord);
  sqlite3VdbeChangeP5(v, OPFLAG_USESEEKRESULT);
  sqlite3ReleaseTempReg(pParse, regRecord);
  sqlite3VdbeAddOp2(v, OP_SorterNext, iSorter, addr2); VdbeCoverage(v);
  sqlite3VdbeJumpHere(v, addr1);

  sqlite3VdbeAddOp1(v, OP_Close, iTab);
  sqlite3VdbeAddOp1(v, OP_Close, iIdx);

      zStmt = 0;
    }

    /* Add an entry in sqlite_master for this index
    */
    sqlite3NestedParse(pParse, 
        "INSERT INTO %Q.%s VALUES('index',%Q,%Q,#%d,%Q);",
        db->aDb[iDb].zDbSName, MASTER_NAME,
        pIndex->zName,
        pTab->zName,
        iMem,
        zStmt
    );
    sqlite3DbFree(db, zStmt);

  /* Generate code to remove the index and from the master table */
  v = sqlite3GetVdbe(pParse);
  if( v ){
    sqlite3BeginWriteOperation(pParse, 1, iDb);
    sqlite3NestedParse(pParse,
       "DELETE FROM %Q.%s WHERE name=%Q AND type='index'",
       db->aDb[iDb].zDbSName, MASTER_NAME, pIndex->zName
    );
    sqlite3ClearStatTables(pParse, iDb, "idx", pIndex->zName);
    sqlite3ChangeCookie(pParse, iDb);
    destroyRootPage(pParse, pIndex->tnum, iDb);
    sqlite3VdbeAddOp4(v, OP_DropIndex, iDb, 0, 0, pIndex->zName, 0);
  }

  assert( nExtra>=1 );
  assert( pSrc!=0 );
  assert( iStart<=pSrc->nSrc );

  /* Allocate additional space if needed */
  if( (u32)pSrc->nSrc+nExtra>pSrc->nAlloc ){
    SrcList *pNew;
    int nAlloc = pSrc->nSrc*2+nExtra;
    int nGot;
    pNew = sqlite3DbRealloc(db, pSrc,
               sizeof(*pSrc) + (nAlloc-1)*sizeof(pSrc->a[0]) );
    if( pNew==0 ){
      assert( db->mallocFailed );
      return pSrc;
    }

  struct SrcList_item *pItem;
  assert( pDatabase==0 || pTable!=0 );  /* Cannot have C without B */
  assert( db!=0 );
  if( pList==0 ){
    pList = sqlite3DbMallocRawNN(db, sizeof(SrcList) );
    if( pList==0 ) return 0;
    pList->nAlloc = 1;
    pList->nSrc = 1;
    memset(&pList->a[0], 0, sizeof(pList->a[0]));
    pList->a[0].iCursor = -1;
  }else{
    pList = sqlite3SrcListEnlarge(db, pList, 1, pList->nSrc);
  }
  if( db->mallocFailed ){
    sqlite3SrcListDelete(db, pList);
    return 0;
  }
  pItem = &pList->a[pList->nSrc-1];
  if( pDatabase && pDatabase->z==0 ){
    pDatabase = 0;

  struct SrcList_item *pItem = pSrc->a;
  Table *pTab;
  assert( pItem && pSrc->nSrc==1 );
  pTab = sqlite3LocateTableItem(pParse, 0, pItem);
  sqlite3DeleteTable(pParse->db, pItem->pTab);
  pItem->pTab = pTab;
  if( pTab ){
    pTab->nTabRef++;
  }
  if( sqlite3IndexedByLookup(pParse, pItem) ){
    pTab = 0;
  }
  return pTab;
}

  **   DELETE FROM table_a WHERE col1=1 ORDER BY col2 LIMIT 1 OFFSET 1
  ** becomes:
  **   DELETE FROM table_a WHERE rowid IN ( 
  **     SELECT rowid FROM table_a WHERE col1=1 ORDER BY col2 LIMIT 1 OFFSET 1
  **   );
  */

  pSelectRowid = sqlite3PExpr(pParse, TK_ROW, 0, 0);
  if( pSelectRowid == 0 ) goto limit_where_cleanup;
  pEList = sqlite3ExprListAppend(pParse, 0, pSelectRowid);
  if( pEList == 0 ) goto limit_where_cleanup;

  /* duplicate the FROM clause as it is needed by both the DELETE/UPDATE tree
  ** and the SELECT subtree. */
  pSelectSrc = sqlite3SrcListDup(pParse->db, pSrc, 0);
  if( pSelectSrc == 0 ) {
    sqlite3ExprListDelete(pParse->db, pEList);
    goto limit_where_cleanup;
  }

  /* generate the SELECT expression tree. */
  pSelect = sqlite3SelectNew(pParse,pEList,pSelectSrc,pWhere,0,0,
                             pOrderBy,0,pLimit,pOffset);
  if( pSelect == 0 ) return 0;

  /* now generate the new WHERE rowid IN clause for the DELETE/UDPATE */
  pWhereRowid = sqlite3PExpr(pParse, TK_ROW, 0, 0);
  pInClause = pWhereRowid ? sqlite3PExpr(pParse, TK_IN, pWhereRowid, 0) : 0;
  sqlite3PExprAddSelect(pParse, pInClause, pSelect);
  return pInClause;

limit_where_cleanup:
  sqlite3ExprDelete(pParse->db, pWhere);
  sqlite3ExprListDelete(pParse->db, pOrderBy);
  sqlite3ExprDelete(pParse->db, pLimit);

    }else{
      if( pPk ){
        /* Add the PK key for this row to the temporary table */
        iKey = ++pParse->nMem;
        nKey = 0;   /* Zero tells OP_Found to use a composite key */
        sqlite3VdbeAddOp4(v, OP_MakeRecord, iPk, nPk, iKey,
            sqlite3IndexAffinityStr(pParse->db, pPk), nPk);
        sqlite3VdbeAddOp4Int(v, OP_IdxInsert, iEphCur, iKey, iPk, nPk);
      }else{
        /* Add the rowid of the row to be deleted to the RowSet */
        nKey = 1;  /* OP_Seek always uses a single rowid */
        sqlite3VdbeAddOp2(v, OP_RowSetAdd, iRowSet, iKey);
      }
    }
  

      if( !IsVirtual(pTab) && aToOpen[iDataCur-iTabCur] ){
        assert( pPk!=0 || pTab->pSelect!=0 );
        sqlite3VdbeAddOp4Int(v, OP_NotFound, iDataCur, addrBypass, iKey, nKey);
        VdbeCoverage(v);
      }
    }else if( pPk ){
      addrLoop = sqlite3VdbeAddOp1(v, OP_Rewind, iEphCur); VdbeCoverage(v);
      sqlite3VdbeAddOp2(v, OP_RowData, iEphCur, iKey);
      assert( nKey==0 );  /* OP_Found will use a composite key */
    }else{
      addrLoop = sqlite3VdbeAddOp3(v, OP_RowSetRead, iRowSet, 0, iKey);
      VdbeCoverage(v);
      assert( nKey==1 );
    }  
  

    }else if( pPk ){
      sqlite3VdbeAddOp2(v, OP_Next, iEphCur, addrLoop+1); VdbeCoverage(v);
      sqlite3VdbeJumpHere(v, addrLoop);
    }else{
      sqlite3VdbeGoto(v, addrLoop);
      sqlite3VdbeJumpHere(v, addrLoop);
    }     








  } /* End non-truncate path */

  /* Update the sqlite_sequence table by storing the content of the
  ** maximum rowid counter values recorded while inserting into
  ** autoincrement tables.
  */
  if( pParse->nested==0 && pParse->pTriggerTab==0 ){

  ** the update-hook is not invoked for rows removed by REPLACE, but the 
  ** pre-update-hook is.
  */ 
  if( pTab->pSelect==0 ){
    u8 p5 = 0;
    sqlite3GenerateRowIndexDelete(pParse, pTab, iDataCur, iIdxCur,0,iIdxNoSeek);
    sqlite3VdbeAddOp2(v, OP_Delete, iDataCur, (count?OPFLAG_NCHANGE:0));
    sqlite3VdbeAppendP4(v, (char*)pTab, P4_TABLE);
    if( eMode!=ONEPASS_OFF ){
      sqlite3VdbeChangeP5(v, OPFLAG_AUXDELETE);
    }
    if( iIdxNoSeek>=0 ){
      sqlite3VdbeAddOp1(v, OP_Delete, iIdxNoSeek);
    }
    if( eMode==ONEPASS_MULTI ) p5 |= OPFLAG_SAVEPOSITION;

  UNUSED_PARAMETER(argc);
  typeHaystack = sqlite3_value_type(argv[0]);
  typeNeedle = sqlite3_value_type(argv[1]);
  if( typeHaystack==SQLITE_NULL || typeNeedle==SQLITE_NULL ) return;
  nHaystack = sqlite3_value_bytes(argv[0]);
  nNeedle = sqlite3_value_bytes(argv[1]);
  if( nNeedle>0 ){
    if( typeHaystack==SQLITE_BLOB && typeNeedle==SQLITE_BLOB ){
      zHaystack = sqlite3_value_blob(argv[0]);
      zNeedle = sqlite3_value_blob(argv[1]);
      assert( zNeedle!=0 );
      assert( zHaystack!=0 || nHaystack==0 );
      isText = 0;
    }else{
      zHaystack = sqlite3_value_text(argv[0]);
      zNeedle = sqlite3_value_text(argv[1]);
      isText = 1;
      if( zHaystack==0 || zNeedle==0 ) return;

    }
    while( nNeedle<=nHaystack && memcmp(zHaystack, zNeedle, nNeedle)!=0 ){
      N++;
      do{
        nHaystack--;
        zHaystack++;
      }while( isText && (zHaystack[0]&0xc0)==0x80 );
    }
    if( nNeedle>nHaystack ) N = 0;
  }
  sqlite3_result_int(context, N);
}

/*
** Implementation of the printf() function.
*/
static void printfFunc(

** case.  Thus  'a' LIKE 'A' would be true. */
static const struct compareInfo likeInfoNorm = { '%', '_',   0, 1 };
/* If SQLITE_CASE_SENSITIVE_LIKE is defined, then the LIKE operator
** is case sensitive causing 'a' LIKE 'A' to be false */
static const struct compareInfo likeInfoAlt = { '%', '_',   0, 0 };

/*
** Possible error returns from patternMatch()
*/
#define SQLITE_MATCH             0
#define SQLITE_NOMATCH           1
#define SQLITE_NOWILDCARDMATCH   2

/*
** Compare two UTF-8 strings for equality where the first string is
** a GLOB or LIKE expression.  Return values:

**
**    SQLITE_MATCH:            Match
**    SQLITE_NOMATCH:          No match
**    SQLITE_NOWILDCARDMATCH:  No match in spite of having * or % wildcards.
**
** Globbing rules:
**
**      '*'       Matches any sequence of zero or more characters.
**
**      '?'       Matches exactly one character.
**