System.Data.SQLite

<?xml version="1.0" encoding="utf-8"?>
<!--
 *
 * sqlite3.props -
 *
 * Written by Joe Mistachkin.
 * Released to the public domain, use at your own risk!
 *
-->
<Project DefaultTargets="Build" xmlns="http://schemas.microsoft.com/developer/msbuild/2003" ToolsVersion="4.0">
  <PropertyGroup Label="UserMacros">
    <SQLITE_MANIFEST_VERSION>3.10.0.0</SQLITE_MANIFEST_VERSION>
    <SQLITE_RC_VERSION>3,10,0,0</SQLITE_RC_VERSION>
    <SQLITE_COMMON_DEFINES>_CRT_SECURE_NO_DEPRECATE;_CRT_SECURE_NO_WARNINGS;_CRT_NONSTDC_NO_DEPRECATE;_CRT_NONSTDC_NO_WARNINGS;SQLITE_THREADSAFE=1;SQLITE_USE_URI=1;SQLITE_ENABLE_COLUMN_METADATA=1;SQLITE_ENABLE_STAT4=1;SQLITE_ENABLE_FTS3=1;SQLITE_ENABLE_LOAD_EXTENSION=1;SQLITE_ENABLE_RTREE=1;SQLITE_SOUNDEX=1;SQLITE_ENABLE_MEMORY_MANAGEMENT=1;SQLITE_ENABLE_API_ARMOR=1</SQLITE_COMMON_DEFINES>
    <SQLITE_EXTRA_DEFINES>SQLITE_PLACEHOLDER=1;SQLITE_HAS_CODEC=1</SQLITE_EXTRA_DEFINES>
    <SQLITE_WINCE_200X_DEFINES>SQLITE_OMIT_WAL=1</SQLITE_WINCE_200X_DEFINES>
    <SQLITE_WINCE_2013_DEFINES>HAVE_ERRNO_H=1;SQLITE_MSVC_LOCALTIME_API=1</SQLITE_WINCE_2013_DEFINES>
    <SQLITE_DEBUG_DEFINES>SQLITE_DEBUG=1;SQLITE_MEMDEBUG=1;SQLITE_ENABLE_EXPENSIVE_ASSERT=1</SQLITE_DEBUG_DEFINES>
    <SQLITE_RELEASE_DEFINES>SQLITE_WIN32_MALLOC=1</SQLITE_RELEASE_DEFINES>
    <SQLITE_DISABLE_WARNINGS>4055;4100;4127;4146;4210;4232;4244;4245;4267;4306;4389;4701;4703;4706</SQLITE_DISABLE_WARNINGS>

<VisualStudioPropertySheet
	ProjectType="Visual C++"
	Version="8.00"
	Name="sqlite3"
	>
	<UserMacro
		Name="SQLITE_MANIFEST_VERSION"
		Value="3.10.0.0"
		PerformEnvironmentSet="true"
	/>
	<UserMacro
		Name="SQLITE_RC_VERSION"
		Value="3,10,0,0"
		PerformEnvironmentSet="true"
	/>
	<UserMacro
		Name="SQLITE_COMMON_DEFINES"
		Value="_CRT_SECURE_NO_DEPRECATE;_CRT_SECURE_NO_WARNINGS;_CRT_NONSTDC_NO_DEPRECATE;_CRT_NONSTDC_NO_WARNINGS;SQLITE_THREADSAFE=1;SQLITE_USE_URI=1;SQLITE_ENABLE_COLUMN_METADATA=1;SQLITE_ENABLE_STAT4=1;SQLITE_ENABLE_FTS3=1;SQLITE_ENABLE_LOAD_EXTENSION=1;SQLITE_ENABLE_RTREE=1;SQLITE_SOUNDEX=1;SQLITE_ENABLE_MEMORY_MANAGEMENT=1;SQLITE_ENABLE_API_ARMOR=1"
		PerformEnvironmentSet="true"
	/>

/******************************************************************************
** This file is an amalgamation of many separate C source files from SQLite
** version 3.10.0.  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        "3.10.0"
#define SQLITE_VERSION_NUMBER 3010000
#define SQLITE_SOURCE_ID      "2015-12-04 13:44:07 4ecbc75b465533cf80e166a9d0879b9afd3fe2be"

/*
** 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

#define SQLITE_IOERR_SHMMAP            (SQLITE_IOERR | (21<<8))
#define SQLITE_IOERR_SEEK              (SQLITE_IOERR | (22<<8))
#define SQLITE_IOERR_DELETE_NOENT      (SQLITE_IOERR | (23<<8))
#define SQLITE_IOERR_MMAP              (SQLITE_IOERR | (24<<8))
#define SQLITE_IOERR_GETTEMPPATH       (SQLITE_IOERR | (25<<8))
#define SQLITE_IOERR_CONVPATH          (SQLITE_IOERR | (26<<8))
#define SQLITE_IOERR_VNODE             (SQLITE_IOERR | (27<<8))
#define SQLITE_IOERR_AUTH              (SQLITE_IOERR | (28<<8))
#define SQLITE_LOCKED_SHAREDCACHE      (SQLITE_LOCKED |  (1<<8))
#define SQLITE_BUSY_RECOVERY           (SQLITE_BUSY   |  (1<<8))
#define SQLITE_BUSY_SNAPSHOT           (SQLITE_BUSY   |  (2<<8))
#define SQLITE_CANTOPEN_NOTEMPDIR      (SQLITE_CANTOPEN | (1<<8))
#define SQLITE_CANTOPEN_ISDIR          (SQLITE_CANTOPEN | (2<<8))
#define SQLITE_CANTOPEN_FULLPATH       (SQLITE_CANTOPEN | (3<<8))
#define SQLITE_CANTOPEN_CONVPATH       (SQLITE_CANTOPEN | (4<<8))

** [sqlite3_malloc()] and the result is stored in the char* variable
** that the fourth parameter of [sqlite3_file_control()] points to.
** The caller is responsible for freeing the memory when done.  As with
** all file-control actions, there is no guarantee that this will actually
** do anything.  Callers should initialize the char* variable to a NULL
** pointer in case this file-control is not implemented.  This file-control
** is intended for diagnostic use only.
**
** <li>[[SQLITE_FCNTL_VFS_POINTER]]
** ^The [SQLITE_FCNTL_VFS_POINTER] opcode finds a pointer to the top-level
** [VFSes] currently in use.  ^(The argument X in
** sqlite3_file_control(db,SQLITE_FCNTL_VFS_POINTER,X) must be
** of type "[sqlite3_vfs] **".  This opcodes will set *X
** to a pointer to the top-level VFS.)^
** ^When there are multiple VFS shims in the stack, this opcode finds the
** upper-most shim only.
**
** <li>[[SQLITE_FCNTL_PRAGMA]]
** ^Whenever a [PRAGMA] statement is parsed, an [SQLITE_FCNTL_PRAGMA] 
** file control is sent to the open [sqlite3_file] object corresponding
** to the database file to which the pragma statement refers. ^The argument
** to the [SQLITE_FCNTL_PRAGMA] file control is an array of
** pointers to strings (char**) in which the second element of the array

#define SQLITE_FCNTL_HAS_MOVED              20
#define SQLITE_FCNTL_SYNC                   21
#define SQLITE_FCNTL_COMMIT_PHASETWO        22
#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

/* 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

** SQLITE_CONFIG_SCRATCH, SQLite avoids unnecessary large
** [sqlite3_malloc|heap allocations].
** This can help [Robson proof|prevent memory allocation failures] due to heap
** fragmentation in low-memory embedded systems.
** </dd>
**
** [[SQLITE_CONFIG_PAGECACHE]] <dt>SQLITE_CONFIG_PAGECACHE</dt>
** <dd> ^The SQLITE_CONFIG_PAGECACHE option specifies a memory pool
** that SQLite can use for the database page cache with the default page
** cache implementation.  
** This configuration option is a no-op if an application-define page
** cache implementation is loaded using the [SQLITE_CONFIG_PCACHE2].

** ^There are three arguments to SQLITE_CONFIG_PAGECACHE: A pointer to
** 8-byte aligned memory (pMem), the size of each page cache line (sz),
** and the number of cache lines (N).
** The sz argument should be the size of the largest database page
** (a power of two between 512 and 65536) plus some extra bytes for each
** page header.  ^The number of extra bytes needed by the page header
** can be determined using [SQLITE_CONFIG_PCACHE_HDRSZ].

** ^It is harmless, apart from the wasted memory,
** for the sz parameter to be larger than necessary.  The pMem
** argument must be either a NULL pointer or a pointer to an 8-byte
** aligned block of memory of at least sz*N bytes, otherwise
** subsequent behavior is undefined.
** ^When pMem is not NULL, SQLite will strive to use the memory provided
** to satisfy page cache needs, falling back to [sqlite3_malloc()] if
** a page cache line is larger than sz bytes or if all of the pMem buffer
** is exhausted.
** ^If pMem is NULL and N is non-zero, then each database connection
** does an initial bulk allocation for page cache memory
** from [sqlite3_malloc()] sufficient for N cache lines if N is positive or
** of -1024*N bytes if N is negative, . ^If additional
** page cache memory is needed beyond what is provided by the initial
** allocation, then SQLite goes to [sqlite3_malloc()] separately for each
** additional cache line. </dd>
**
** [[SQLITE_CONFIG_HEAP]] <dt>SQLITE_CONFIG_HEAP</dt>
** <dd> ^The SQLITE_CONFIG_HEAP option specifies a static memory buffer 
** that SQLite will use for all of its dynamic memory allocation needs
** beyond those provided for by [SQLITE_CONFIG_SCRATCH] and
** [SQLITE_CONFIG_PAGECACHE].
** ^The SQLITE_CONFIG_HEAP option is only available if SQLite is compiled

** and makes other simplifications to the WHERE clause in an attempt to
** get as many WHERE clause terms into the form shown above as possible.
** ^The aConstraint[] array only reports WHERE clause terms that are
** relevant to the particular virtual table being queried.
**
** ^Information about the ORDER BY clause is stored in aOrderBy[].
** ^Each term of aOrderBy records a column of the ORDER BY clause.
**
** The colUsed field indicates which columns of the virtual table may be
** required by the current scan. Virtual table columns are numbered from
** zero in the order in which they appear within the CREATE TABLE statement
** passed to sqlite3_declare_vtab(). For the first 63 columns (columns 0-62),
** the corresponding bit is set within the colUsed mask if the column may be
** required by SQLite. If the table has at least 64 columns and any column
** to the right of the first 63 is required, then bit 63 of colUsed is also
** set. In other words, column iCol may be required if the expression
** (colUsed & ((sqlite3_uint64)1 << (iCol>=63 ? 63 : iCol))) evaluates to 
** non-zero.
**
** The [xBestIndex] method must fill aConstraintUsage[] with information
** about what parameters to pass to xFilter.  ^If argvIndex>0 then
** the right-hand side of the corresponding aConstraint[] is evaluated
** and becomes the argvIndex-th entry in argv.  ^(If aConstraintUsage[].omit
** is true, then the constraint is assumed to be fully handled by the
** virtual table and is not checked again by SQLite.)^

  int needToFreeIdxStr;      /* Free idxStr using sqlite3_free() if true */
  int orderByConsumed;       /* True if output is already ordered */
  double estimatedCost;           /* Estimated cost of using this index */
  /* Fields below are only available in SQLite 3.8.2 and later */
  sqlite3_int64 estimatedRows;    /* Estimated number of rows returned */
  /* Fields below are only available in SQLite 3.9.0 and later */
  int idxFlags;              /* Mask of SQLITE_INDEX_SCAN_* flags */
  /* Fields below are only available in SQLite 3.10.0 and later */
  sqlite3_uint64 colUsed;    /* Input: Mask of columns used by statement */
};

/*
** CAPI3REF: Virtual Table Scan Flags
*/
#define SQLITE_INDEX_SCAN_UNIQUE      1     /* Scan visits at most 1 row */

/*
** CAPI3REF: Virtual Table Constraint Operator Codes
**
** These macros defined the allowed values for the
** [sqlite3_index_info].aConstraint[].op field.  Each value represents
** an operator that is part of a constraint term in the wHERE clause of
** a query that uses a [virtual table].
*/
#define SQLITE_INDEX_CONSTRAINT_EQ      2
#define SQLITE_INDEX_CONSTRAINT_GT      4
#define SQLITE_INDEX_CONSTRAINT_LE      8
#define SQLITE_INDEX_CONSTRAINT_LT     16
#define SQLITE_INDEX_CONSTRAINT_GE     32
#define SQLITE_INDEX_CONSTRAINT_MATCH  64
#define SQLITE_INDEX_CONSTRAINT_LIKE   65
#define SQLITE_INDEX_CONSTRAINT_GLOB   66
#define SQLITE_INDEX_CONSTRAINT_REGEXP 67

/*
** CAPI3REF: Register A Virtual Table Implementation
** METHOD: sqlite3
**
** ^These routines are used to register a new [virtual table module] name.
** ^Module names must be registered before

** [[SQLITE_STATUS_SCRATCH_SIZE]] ^(<dt>SQLITE_STATUS_SCRATCH_SIZE</dt>
** <dd>This parameter records the largest memory allocation request
** handed to [scratch memory allocator].  Only the value returned in the
** *pHighwater parameter to [sqlite3_status()] is of interest.  
** The value written into the *pCurrent parameter is undefined.</dd>)^
**
** [[SQLITE_STATUS_PARSER_STACK]] ^(<dt>SQLITE_STATUS_PARSER_STACK</dt>
** <dd>The *pHighwater parameter records the deepest parser stack. 
** The *pCurrent value is undefined.  The *pHighwater value is only
** meaningful if SQLite is compiled with [YYTRACKMAXSTACKDEPTH].</dd>)^
** </dl>
**
** New status parameters may be added from time to time.
*/
#define SQLITE_STATUS_MEMORY_USED          0
#define SQLITE_STATUS_PAGECACHE_USED       1

*/
SQLITE_API int SQLITE_STDCALL sqlite3_stricmp(const char *, const char *);
SQLITE_API int SQLITE_STDCALL sqlite3_strnicmp(const char *, const char *, int);

/*
** CAPI3REF: String Globbing
*
** ^The [sqlite3_strglob(P,X)] interface returns zero if and only if
** string X matches the [GLOB] pattern P.
** ^The definition of [GLOB] pattern matching used in
** [sqlite3_strglob(P,X)] is the same as for the "X GLOB P" operator in the
** SQL dialect understood by SQLite.  ^The [sqlite3_strglob(P,X)] function
** is case sensitive.
**
** Note that this routine returns zero on a match and non-zero if the strings
** do not match, the same as [sqlite3_stricmp()] and [sqlite3_strnicmp()].
**
** See also: [sqlite3_strlike()].
*/
SQLITE_API int SQLITE_STDCALL sqlite3_strglob(const char *zGlob, const char *zStr);

/*
** CAPI3REF: String LIKE Matching
*
** ^The [sqlite3_strlike(P,X,E)] interface returns zero if and only if
** string X matches the [LIKE] pattern P with escape character E.
** ^The definition of [LIKE] pattern matching used in
** [sqlite3_strlike(P,X,E)] is the same as for the "X LIKE P ESCAPE E"
** operator in the SQL dialect understood by SQLite.  ^For "X LIKE P" without
** the ESCAPE clause, set the E parameter of [sqlite3_strlike(P,X,E)] to 0.
** ^As with the LIKE operator, the [sqlite3_strlike(P,X,E)] function is case
** insensitive - equivalent upper and lower case ASCII characters match
** one another.
**
** ^The [sqlite3_strlike(P,X,E)] function matches Unicode characters, though
** only ASCII characters are case folded.
**
** Note that this routine returns zero on a match and non-zero if the strings
** do not match, the same as [sqlite3_stricmp()] and [sqlite3_strnicmp()].
**
** See also: [sqlite3_strglob()].
*/
SQLITE_API int SQLITE_STDCALL sqlite3_strlike(const char *zGlob, const char *zStr, unsigned int cEsc);

/*
** CAPI3REF: Error Logging Interface
**
** ^The [sqlite3_log()] interface writes a message into the [error log]
** established by the [SQLITE_CONFIG_LOG] option to [sqlite3_config()].
** ^If logging is enabled, the zFormat string and subsequent arguments are

** ^Zero all [sqlite3_stmt_scanstatus()] related event counters.
**
** This API is only available if the library is built with pre-processor
** symbol [SQLITE_ENABLE_STMT_SCANSTATUS] defined.
*/
SQLITE_API void SQLITE_STDCALL sqlite3_stmt_scanstatus_reset(sqlite3_stmt*);

/*
** CAPI3REF: Flush caches to disk mid-transaction
**
** If a write-transaction is open when this function is called, any dirty
** pages in the pager-cache that are not currently in use are written out 
** to disk. A dirty page may be in use if a database cursor created by an
** active SQL statement is reading from it, or if it is page 1 of a database
** file (page 1 is always "in use"). Dirty pages are flushed for all
** databases - "main", "temp" and any attached databases.
**
** If this function needs to obtain extra database locks before dirty pages 
** can be flushed to disk, it does so. If said locks cannot be obtained 
** immediately and there is a busy-handler callback configured, it is invoked
** in the usual manner. If the required lock still cannot be obtained, then
** the database is skipped and an attempt made to flush any dirty pages
** belonging to the next (if any) database. If any databases are skipped
** because locks cannot be obtained, but no other error occurs, this
** function returns SQLITE_BUSY.
**
** If any other error occurs while flushing dirty pages to disk (for
** example an IO error or out-of-memory condition), then processing is
** abandoned and an SQLite error code returned to the caller immediately.
**
** Otherwise, if no error occurs, SQLITE_OK is returned.
**
** This function does not set the database handle error code or message
** returned by the sqlite3_errcode() and sqlite3_errmsg() functions.
*/
SQLITE_API int SQLITE_STDCALL sqlite3_db_cacheflush(sqlite3*);

/*
** 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

#define TK_TO_TEXT                        143
#define TK_TO_BLOB                        144
#define TK_TO_NUMERIC                     145
#define TK_TO_INT                         146
#define TK_TO_REAL                        147
#define TK_ISNOT                          148
#define TK_END_OF_FILE                    149


#define TK_UNCLOSED_STRING                150
#define TK_FUNCTION                       151
#define TK_COLUMN                         152
#define TK_AGG_FUNCTION                   153
#define TK_AGG_COLUMN                     154
#define TK_UMINUS                         155
#define TK_UPLUS                          156
#define TK_REGISTER                       157
#define TK_ASTERISK                       158
#define TK_SPACE                          159
#define TK_ILLEGAL                        160

/* The token codes above must all fit in 8 bits */
#define TKFLG_MASK           0xff  

/* Flags that can be added to a token code when it is not
** being stored in a u8: */
#define TKFLG_DONTFOLD       0x100  /* Omit constant folding optimizations */

/************** End of parse.h ***********************************************/
/************** Continuing where we left off in sqliteInt.h ******************/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <assert.h>

** pagecaches for each database connection.  A positive number is the
** number of pages.  A negative number N translations means that a buffer
** of -1024*N bytes is allocated and used for as many pages as it will hold.
*/
#ifndef SQLITE_DEFAULT_PCACHE_INITSZ
# define SQLITE_DEFAULT_PCACHE_INITSZ 100
#endif


/*
** GCC does not define the offsetof() macro so we'll have to do it
** ourselves.
*/
#ifndef offsetof
#define offsetof(STRUCTURE,FIELD) ((int)((char*)&((STRUCTURE*)0)->FIELD))

#define BTREE_OMIT_JOURNAL  1  /* Do not create or use a rollback journal */
#define BTREE_MEMORY        2  /* This is an in-memory DB */
#define BTREE_SINGLE        4  /* The file contains at most 1 b-tree */
#define BTREE_UNORDERED     8  /* Use of a hash implementation is OK */

SQLITE_PRIVATE int sqlite3BtreeClose(Btree*);
SQLITE_PRIVATE int sqlite3BtreeSetCacheSize(Btree*,int);
SQLITE_PRIVATE int sqlite3BtreeSetSpillSize(Btree*,int);
#if SQLITE_MAX_MMAP_SIZE>0
SQLITE_PRIVATE   int sqlite3BtreeSetMmapLimit(Btree*,sqlite3_int64);
#endif
SQLITE_PRIVATE int sqlite3BtreeSetPagerFlags(Btree*,unsigned);
SQLITE_PRIVATE int sqlite3BtreeSyncDisabled(Btree*);
SQLITE_PRIVATE int sqlite3BtreeSetPageSize(Btree *p, int nPagesize, int nReserve, int eFix);
SQLITE_PRIVATE int sqlite3BtreeGetPageSize(Btree*);

#define BTREE_TEXT_ENCODING       5
#define BTREE_USER_VERSION        6
#define BTREE_INCR_VACUUM         7
#define BTREE_APPLICATION_ID      8
#define BTREE_DATA_VERSION        15  /* A virtual meta-value */

/*
** Kinds of hints that can be passed into the sqlite3BtreeCursorHint()
** interface.
**
** BTREE_HINT_RANGE  (arguments: Expr*, Mem*)
**
**     The first argument is an Expr* (which is guaranteed to be constant for
**     the lifetime of the cursor) that defines constraints on which rows
**     might be fetched with this cursor.  The Expr* tree may contain
**     TK_REGISTER nodes that refer to values stored in the array of registers
**     passed as the second parameter.  In other words, if Expr.op==TK_REGISTER
**     then the value of the node is the value in Mem[pExpr.iTable].  Any
**     TK_COLUMN node in the expression tree refers to the Expr.iColumn-th
**     column of the b-tree of the cursor.  The Expr tree will not contain
**     any function calls nor subqueries nor references to b-trees other than
**     the cursor being hinted.
**
**     The design of the _RANGE hint is aid b-tree implementations that try
**     to prefetch content from remote machines - to provide those
**     implementations with limits on what needs to be prefetched and thereby
**     reduce network bandwidth.
**
** Note that BTREE_HINT_FLAGS with BTREE_BULKLOAD is the only hint used by
** standard SQLite.  The other hints are provided for extentions that use
** the SQLite parser and code generator but substitute their own storage
** engine.
*/
#define BTREE_HINT_RANGE 0       /* Range constraints on queries */

/*
** Values that may be OR'd together to form the argument to the
** BTREE_HINT_FLAGS hint for sqlite3BtreeCursorHint():
**
** The BTREE_BULKLOAD flag is set on index cursors when the index is going
** to be filled with content that is already in sorted order.
**
** The BTREE_SEEK_EQ flag is set on cursors that will get OP_SeekGE or
** OP_SeekLE opcodes for a range search, but where the range of entries
** selected will all have the same key.  In other words, the cursor will
** be used only for equality key searches.
**
*/
#define BTREE_BULKLOAD 0x00000001  /* Used to full index in sorted order */
#define BTREE_SEEK_EQ  0x00000002  /* EQ seeks only - no range seeks */

/* 
** Flags passed as the third argument to sqlite3BtreeCursor().
**
** For read-only cursors the wrFlag argument is always zero. For read-write
** cursors it may be set to either (BTREE_WRCSR|BTREE_FORDELETE) or
** (BTREE_WRCSR). If the BTREE_FORDELETE flag is set, then the cursor will
** only be used by SQLite for the following:
**
**   * to seek to and delete specific entries, and/or
**
**   * to read values that will be used to create keys that other
**     BTREE_FORDELETE cursors will seek to and delete.
*/
#define BTREE_WRCSR     0x00000004     /* read-write cursor */
#define BTREE_FORDELETE 0x00000008     /* Cursor is for seek/delete only */

SQLITE_PRIVATE int sqlite3BtreeCursor(
  Btree*,                              /* BTree containing table to open */
  int iTable,                          /* Index of root page */
  int wrFlag,                          /* 1 for writing.  0 for read-only */
  struct KeyInfo*,                     /* First argument to compare function */
  BtCursor *pCursor                    /* Space to write cursor structure */
);
SQLITE_PRIVATE int sqlite3BtreeCursorSize(void);
SQLITE_PRIVATE void sqlite3BtreeCursorZero(BtCursor*);
SQLITE_PRIVATE void sqlite3BtreeCursorHintFlags(BtCursor*, unsigned);
#ifdef SQLITE_ENABLE_CURSOR_HINTS
SQLITE_PRIVATE void sqlite3BtreeCursorHint(BtCursor*, int, ...);
#endif

SQLITE_PRIVATE int sqlite3BtreeCloseCursor(BtCursor*);
SQLITE_PRIVATE int sqlite3BtreeMovetoUnpacked(
  BtCursor*,
  UnpackedRecord *pUnKey,
  i64 intKey,
  int bias,

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

SQLITE_PRIVATE int sqlite3BtreePutData(BtCursor*, u32 offset, u32 amt, void*);
SQLITE_PRIVATE void sqlite3BtreeIncrblobCursor(BtCursor *);
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

    sqlite3_context *pCtx; /* Used when p4type is P4_FUNCCTX */
    CollSeq *pColl;        /* Used when p4type is P4_COLLSEQ */
    Mem *pMem;             /* Used when p4type is P4_MEM */
    VTable *pVtab;         /* Used when p4type is P4_VTAB */
    KeyInfo *pKeyInfo;     /* Used when p4type is P4_KEYINFO */
    int *ai;               /* Used when p4type is P4_INTARRAY */
    SubProgram *pProgram;  /* Used when p4type is P4_SUBPROGRAM */
#ifdef SQLITE_ENABLE_CURSOR_HINTS
    Expr *pExpr;           /* Used when p4type is P4_EXPR */
#endif
    int (*xAdvance)(BtCursor *, int *);
  } p4;
#ifdef SQLITE_ENABLE_EXPLAIN_COMMENTS
  char *zComment;          /* Comment to improve readability */
#endif
#ifdef VDBE_PROFILE
  u32 cnt;                 /* Number of times this instruction was executed */

*/
#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  (-4)  /* P4 is a pointer to a CollSeq structure */
#define P4_FUNCDEF  (-5)  /* P4 is a pointer to a FuncDef structure */
#define P4_KEYINFO  (-6)  /* P4 is a pointer to a KeyInfo structure */
#define P4_EXPR     (-7)  /* P4 is a pointer to an Expr tree */
#define P4_MEM      (-8)  /* P4 is a pointer to a Mem*    structure */
#define P4_TRANSIENT  0   /* P4 is a pointer to a transient string */
#define P4_VTAB     (-10) /* P4 is a pointer to an sqlite3_vtab structure */
#define P4_MPRINTF  (-11) /* P4 is a string obtained from sqlite3_mprintf() */
#define P4_REAL     (-12) /* P4 is a 64-bit floating point value */
#define P4_INT64    (-13) /* P4 is a 64-bit signed integer */
#define P4_INT32    (-14) /* P4 is a 32-bit signed integer */

/*
** The makefile scans the vdbe.c source file and creates the "opcodes.h"
** header file that defines a number for each opcode used by the VDBE.
*/
/************** Include opcodes.h in the middle of vdbe.h ********************/
/************** Begin file opcodes.h *****************************************/
/* Automatically generated.  Do not edit */
/* See the tool/mkopcodeh.tcl script for details */
#define OP_Savepoint       1
#define OP_AutoCommit      2
#define OP_Transaction     3
#define OP_SorterNext      4
#define OP_PrevIfOpen      5
#define OP_NextIfOpen      6
#define OP_Prev            7

#define OP_Null           26 /* synopsis: r[P2..P3]=NULL                   */
#define OP_SoftNull       27 /* synopsis: r[P1]=NULL                       */
#define OP_Blob           28 /* synopsis: r[P2]=P4 (len=P1)                */
#define OP_Variable       29 /* synopsis: r[P2]=parameter(P1,P4)           */
#define OP_Move           30 /* synopsis: r[P2@P3]=r[P1@P3]                */
#define OP_Copy           31 /* synopsis: r[P2@P3+1]=r[P1@P3+1]            */
#define OP_SCopy          32 /* synopsis: r[P2]=r[P1]                      */
#define OP_IntCopy        33 /* synopsis: r[P2]=r[P1]                      */
#define OP_ResultRow      34 /* synopsis: output=r[P1@P2]                  */
#define OP_CollSeq        35
#define OP_Function0      36 /* synopsis: r[P3]=func(r[P2@P5])             */
#define OP_Function       37 /* synopsis: r[P3]=func(r[P2@P5])             */
#define OP_AddImm         38 /* synopsis: r[P1]=r[P1]+P2                   */
#define OP_MustBeInt      39
#define OP_RealAffinity   40
#define OP_Cast           41 /* synopsis: affinity(r[P1])                  */
#define OP_Permutation    42
#define OP_Compare        43 /* synopsis: r[P1@P3] <-> r[P2@P3]            */
#define OP_Jump           44
#define OP_Once           45
#define OP_If             46
#define OP_IfNot          47
#define OP_Column         48 /* synopsis: r[P3]=PX                         */
#define OP_Affinity       49 /* synopsis: affinity(r[P1@P2])               */
#define OP_MakeRecord     50 /* synopsis: r[P3]=mkrec(r[P1@P2])            */
#define OP_Count          51 /* synopsis: r[P2]=count()                    */
#define OP_ReadCookie     52
#define OP_SetCookie      53
#define OP_ReopenIdx      54 /* synopsis: root=P2 iDb=P3                   */
#define OP_OpenRead       55 /* synopsis: root=P2 iDb=P3                   */
#define OP_OpenWrite      56 /* synopsis: root=P2 iDb=P3                   */
#define OP_OpenAutoindex  57 /* synopsis: nColumn=P2                       */
#define OP_OpenEphemeral  58 /* synopsis: nColumn=P2                       */
#define OP_SorterOpen     59
#define OP_SequenceTest   60 /* synopsis: if( cursor[P1].ctr++ ) pc = P2   */
#define OP_OpenPseudo     61 /* synopsis: P3 columns in r[P2]              */
#define OP_Close          62
#define OP_ColumnsUsed    63
#define OP_SeekLT         64 /* synopsis: key=r[P3@P4]                     */
#define OP_SeekLE         65 /* synopsis: key=r[P3@P4]                     */
#define OP_SeekGE         66 /* synopsis: key=r[P3@P4]                     */
#define OP_SeekGT         67 /* synopsis: key=r[P3@P4]                     */
#define OP_Seek           68 /* synopsis: intkey=r[P2]                     */

#define OP_NoConflict     69 /* synopsis: key=r[P3@P4]                     */
#define OP_NotFound       70 /* synopsis: key=r[P3@P4]                     */
#define OP_Or             71 /* same as TK_OR, synopsis: r[P3]=(r[P1] || r[P2]) */
#define OP_And            72 /* same as TK_AND, synopsis: r[P3]=(r[P1] && r[P2]) */
#define OP_Found          73 /* synopsis: key=r[P3@P4]                     */
#define OP_NotExists      74 /* synopsis: intkey=r[P3]                     */
#define OP_Sequence       75 /* synopsis: r[P2]=cursor[P1].ctr++           */

#define OP_IsNull         76 /* same as TK_ISNULL, synopsis: if r[P1]==NULL goto P2 */
#define OP_NotNull        77 /* same as TK_NOTNULL, synopsis: if r[P1]!=NULL goto P2 */
#define OP_Ne             78 /* same as TK_NE, synopsis: if r[P1]!=r[P3] goto P2 */
#define OP_Eq             79 /* same as TK_EQ, synopsis: if r[P1]==r[P3] goto P2 */
#define OP_Gt             80 /* same as TK_GT, synopsis: if r[P1]>r[P3] goto P2 */
#define OP_Le             81 /* same as TK_LE, synopsis: if r[P1]<=r[P3] goto P2 */
#define OP_Lt             82 /* same as TK_LT, synopsis: if r[P1]<r[P3] goto P2 */
#define OP_Ge             83 /* same as TK_GE, synopsis: if r[P1]>=r[P3] goto P2 */
#define OP_NewRowid       84 /* synopsis: r[P2]=rowid                      */
#define OP_BitAnd         85 /* same as TK_BITAND, synopsis: r[P3]=r[P1]&r[P2] */
#define OP_BitOr          86 /* same as TK_BITOR, synopsis: r[P3]=r[P1]|r[P2] */
#define OP_ShiftLeft      87 /* same as TK_LSHIFT, synopsis: r[P3]=r[P2]<<r[P1] */
#define OP_ShiftRight     88 /* same as TK_RSHIFT, synopsis: r[P3]=r[P2]>>r[P1] */
#define OP_Add            89 /* same as TK_PLUS, synopsis: r[P3]=r[P1]+r[P2] */
#define OP_Subtract       90 /* same as TK_MINUS, synopsis: r[P3]=r[P2]-r[P1] */
#define OP_Multiply       91 /* same as TK_STAR, synopsis: r[P3]=r[P1]*r[P2] */
#define OP_Divide         92 /* same as TK_SLASH, synopsis: r[P3]=r[P2]/r[P1] */
#define OP_Remainder      93 /* same as TK_REM, synopsis: r[P3]=r[P2]%r[P1] */
#define OP_Concat         94 /* same as TK_CONCAT, synopsis: r[P3]=r[P2]+r[P1] */
#define OP_Insert         95 /* synopsis: intkey=r[P3] data=r[P2]          */
#define OP_BitNot         96 /* same as TK_BITNOT, synopsis: r[P1]= ~r[P1] */
#define OP_String8        97 /* same as TK_STRING, synopsis: r[P2]='P4'    */
#define OP_InsertInt      98 /* synopsis: intkey=P3 data=r[P2]             */
#define OP_Delete         99
#define OP_ResetCount    100
#define OP_SorterCompare 101 /* synopsis: if key(P1)!=trim(r[P3],P4) goto P2 */
#define OP_SorterData    102 /* synopsis: r[P2]=data                       */
#define OP_RowKey        103 /* synopsis: r[P2]=key                        */
#define OP_RowData       104 /* synopsis: r[P2]=data                       */
#define OP_Rowid         105 /* synopsis: r[P2]=rowid                      */
#define OP_NullRow       106
#define OP_Last          107
#define OP_SorterSort    108
#define OP_Sort          109
#define OP_Rewind        110
#define OP_SorterInsert  111
#define OP_IdxInsert     112 /* synopsis: key=r[P2]                        */
#define OP_IdxDelete     113 /* synopsis: key=r[P2@P3]                     */
#define OP_IdxRowid      114 /* synopsis: r[P2]=rowid                      */
#define OP_IdxLE         115 /* synopsis: key=r[P3@P4]                     */
#define OP_IdxGT         116 /* synopsis: key=r[P3@P4]                     */
#define OP_IdxLT         117 /* synopsis: key=r[P3@P4]                     */
#define OP_IdxGE         118 /* synopsis: key=r[P3@P4]                     */
#define OP_Destroy       119
#define OP_Clear         120
#define OP_ResetSorter   121
#define OP_CreateIndex   122 /* synopsis: r[P2]=root iDb=P1                */
#define OP_CreateTable   123 /* synopsis: r[P2]=root iDb=P1                */
#define OP_ParseSchema   124
#define OP_LoadAnalysis  125
#define OP_DropTable     126
#define OP_DropIndex     127
#define OP_DropTrigger   128
#define OP_IntegrityCk   129
#define OP_RowSetAdd     130 /* synopsis: rowset(P1)=r[P2]                 */
#define OP_RowSetRead    131 /* synopsis: r[P3]=rowset(P1)                 */
#define OP_RowSetTest    132 /* synopsis: if r[P3] in rowset(P1) goto P2   */

#define OP_Real          133 /* same as TK_FLOAT, synopsis: r[P2]=P4       */
#define OP_Program       134
#define OP_Param         135
#define OP_FkCounter     136 /* synopsis: fkctr[P1]+=P2                    */
#define OP_FkIfZero      137 /* synopsis: if fkctr[P1]==0 goto P2          */
#define OP_MemMax        138 /* synopsis: r[P1]=max(r[P1],r[P2])           */
#define OP_IfPos         139 /* synopsis: if r[P1]>0 then r[P1]-=P3, goto P2 */
#define OP_SetIfNotPos   140 /* synopsis: if r[P1]<=0 then r[P2]=P3        */
#define OP_IfNotZero     141 /* synopsis: if r[P1]!=0 then r[P1]-=P3, goto P2 */
#define OP_DecrJumpZero  142 /* synopsis: if (--r[P1])==0 goto P2          */
#define OP_JumpZeroIncr  143 /* synopsis: if (r[P1]++)==0 ) goto P2        */
#define OP_AggStep0      144 /* synopsis: accum=r[P3] step(r[P2@P5])       */
#define OP_AggStep       145 /* synopsis: accum=r[P3] step(r[P2@P5])       */
#define OP_AggFinal      146 /* synopsis: accum=r[P1] N=P2                 */
#define OP_IncrVacuum    147
#define OP_Expire        148
#define OP_TableLock     149 /* synopsis: iDb=P1 root=P2 write=P3          */
#define OP_VBegin        150
#define OP_VCreate       151
#define OP_VDestroy      152
#define OP_VOpen         153
#define OP_VColumn       154 /* synopsis: r[P3]=vcolumn(P2)                */
#define OP_VNext         155
#define OP_VRename       156
#define OP_Pagecount     157
#define OP_MaxPgcnt      158
#define OP_Init          159 /* synopsis: Start at P2                      */
#define OP_CursorHint    160
#define OP_Noop          161
#define OP_Explain       162


/* 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            0x0001  /* jump:  P2 holds jmp target */
#define OPFLG_IN1             0x0002  /* in1:   P1 is an input */
#define OPFLG_IN2             0x0004  /* in2:   P2 is an input */
#define OPFLG_IN3             0x0008  /* in3:   P3 is an input */
#define OPFLG_OUT2            0x0010  /* out2:  P2 is an output */
#define OPFLG_OUT3            0x0020  /* out3:  P3 is an output */
#define OPFLG_INITIALIZER {\
/*   0 */ 0x00, 0x00, 0x00, 0x00, 0x01, 0x01, 0x01, 0x01,\
/*   8 */ 0x01, 0x00, 0x10, 0x00, 0x01, 0x00, 0x01, 0x01,\
/*  16 */ 0x02, 0x01, 0x02, 0x12, 0x03, 0x08, 0x00, 0x10,\
/*  24 */ 0x10, 0x10, 0x10, 0x00, 0x10, 0x10, 0x00, 0x00,\
/*  32 */ 0x10, 0x10, 0x00, 0x00, 0x00, 0x00, 0x02, 0x03,\
/*  40 */ 0x02, 0x02, 0x00, 0x00, 0x01, 0x01, 0x03, 0x03,\
/*  48 */ 0x00, 0x00, 0x00, 0x10, 0x10, 0x08, 0x00, 0x00,\
/*  56 */ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,\
/*  64 */ 0x09, 0x09, 0x09, 0x09, 0x04, 0x09, 0x09, 0x26,\
/*  72 */ 0x26, 0x09, 0x09, 0x10, 0x03, 0x03, 0x0b, 0x0b,\
/*  80 */ 0x0b, 0x0b, 0x0b, 0x0b, 0x10, 0x26, 0x26, 0x26,\
/*  88 */ 0x26, 0x26, 0x26, 0x26, 0x26, 0x26, 0x26, 0x00,\
/*  96 */ 0x12, 0x10, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,\
/* 104 */ 0x00, 0x10, 0x00, 0x01, 0x01, 0x01, 0x01, 0x04,\
/* 112 */ 0x04, 0x00, 0x10, 0x01, 0x01, 0x01, 0x01, 0x10,\
/* 120 */ 0x00, 0x00, 0x10, 0x10, 0x00, 0x00, 0x00, 0x00,\
/* 128 */ 0x00, 0x00, 0x06, 0x23, 0x0b, 0x10, 0x01, 0x10,\
/* 136 */ 0x00, 0x01, 0x04, 0x03, 0x06, 0x03, 0x03, 0x03,\
/* 144 */ 0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x00, 0x00,\
/* 152 */ 0x00, 0x00, 0x00, 0x01, 0x00, 0x10, 0x10, 0x01,\
/* 160 */ 0x00, 0x00, 0x00,}

/************** End of opcodes.h *********************************************/
/************** Continuing where we left off in vdbe.h ***********************/

/*
** Prototypes for the VDBE interface.  See comments on the implementation
** for a description of what each of these routines does.

#define PAGER_JOURNALMODE_PERSIST     1   /* Commit by zeroing journal header */
#define PAGER_JOURNALMODE_OFF         2   /* Journal omitted.  */
#define PAGER_JOURNALMODE_TRUNCATE    3   /* Commit by truncating journal */
#define PAGER_JOURNALMODE_MEMORY      4   /* In-memory journal file */
#define PAGER_JOURNALMODE_WAL         5   /* Use write-ahead logging */

/*
** Flags that make up the mask passed to sqlite3PagerGet().
*/
#define PAGER_GET_NOCONTENT     0x01  /* Do not load data from disk */
#define PAGER_GET_READONLY      0x02  /* Read-only page is acceptable */

/*
** Flags for sqlite3PagerSetFlags()
*/

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*);
#endif
SQLITE_PRIVATE int sqlite3PagerMaxPageCount(Pager*, int);
SQLITE_PRIVATE void sqlite3PagerSetCachesize(Pager*, int);
SQLITE_PRIVATE int sqlite3PagerSetSpillsize(Pager*, int);
SQLITE_PRIVATE void sqlite3PagerSetMmapLimit(Pager *, sqlite3_int64);
SQLITE_PRIVATE void sqlite3PagerShrink(Pager*);
SQLITE_PRIVATE void sqlite3PagerSetFlags(Pager*,unsigned);
SQLITE_PRIVATE int sqlite3PagerLockingMode(Pager *, int);
SQLITE_PRIVATE int sqlite3PagerSetJournalMode(Pager *, int);
SQLITE_PRIVATE int sqlite3PagerGetJournalMode(Pager*);
SQLITE_PRIVATE int sqlite3PagerOkToChangeJournalMode(Pager*);
SQLITE_PRIVATE i64 sqlite3PagerJournalSizeLimit(Pager *, i64);
SQLITE_PRIVATE sqlite3_backup **sqlite3PagerBackupPtr(Pager*);
SQLITE_PRIVATE int sqlite3PagerFlush(Pager*);

/* Functions used to obtain and release page references. */ 
SQLITE_PRIVATE int sqlite3PagerGet(Pager *pPager, Pgno pgno, DbPage **ppPage, int clrFlag);

SQLITE_PRIVATE DbPage *sqlite3PagerLookup(Pager *pPager, Pgno pgno);
SQLITE_PRIVATE void sqlite3PagerRef(DbPage*);
SQLITE_PRIVATE void sqlite3PagerUnref(DbPage*);
SQLITE_PRIVATE void sqlite3PagerUnrefNotNull(DbPage*);

/* Operations on page references. */
SQLITE_PRIVATE int sqlite3PagerWrite(DbPage*);

SQLITE_PRIVATE u8 sqlite3PagerIsreadonly(Pager*);
SQLITE_PRIVATE u32 sqlite3PagerDataVersion(Pager*);
#ifdef SQLITE_DEBUG
SQLITE_PRIVATE   int sqlite3PagerRefcount(Pager*);
#endif
SQLITE_PRIVATE int sqlite3PagerMemUsed(Pager*);
SQLITE_PRIVATE const char *sqlite3PagerFilename(Pager*, int);
SQLITE_PRIVATE sqlite3_vfs *sqlite3PagerVfs(Pager*);
SQLITE_PRIVATE sqlite3_file *sqlite3PagerFile(Pager*);
SQLITE_PRIVATE const char *sqlite3PagerJournalname(Pager*);
SQLITE_PRIVATE int sqlite3PagerNosync(Pager*);
SQLITE_PRIVATE void *sqlite3PagerTempSpace(Pager*);
SQLITE_PRIVATE int sqlite3PagerIsMemdb(Pager*);
SQLITE_PRIVATE void sqlite3PagerCacheStat(Pager *, int, int, int *);
SQLITE_PRIVATE void sqlite3PagerClearCache(Pager *);

** the total number of pages cached by purgeable pager-caches to the sum
** of the suggested cache-sizes.
*/
SQLITE_PRIVATE void sqlite3PcacheSetCachesize(PCache *, int);
#ifdef SQLITE_TEST
SQLITE_PRIVATE int sqlite3PcacheGetCachesize(PCache *);
#endif

/* Set or get the suggested spill-size for the specified pager-cache.
**
** The spill-size is the minimum number of pages in cache before the cache
** will attempt to spill dirty pages by calling xStress.
*/
SQLITE_PRIVATE int sqlite3PcacheSetSpillsize(PCache *, int);

/* Free up as much memory as possible from the page cache */
SQLITE_PRIVATE void sqlite3PcacheShrink(PCache*);

#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
/* Try to return memory used by the pcache module to the main memory heap */
SQLITE_PRIVATE int sqlite3PcacheReleaseMemory(int);

#define SQLITE_DistinctOpt    0x0020   /* DISTINCT using indexes */
#define SQLITE_CoverIdxScan   0x0040   /* Covering index scans */
#define SQLITE_OrderByIdxJoin 0x0080   /* ORDER BY of joins via index */
#define SQLITE_SubqCoroutine  0x0100   /* Evaluate subqueries as coroutines */
#define SQLITE_Transitive     0x0200   /* Transitive constraints */
#define SQLITE_OmitNoopJoin   0x0400   /* Omit unused tables in joins */
#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.
*/
#ifndef SQLITE_OMIT_BUILTIN_TEST
#define OptimizationDisabled(db, mask)  (((db)->dbOptFlags&(mask))!=0)

  int nRef;
  void (*xDestroy)(void *);
  void *pUserData;
};

/*
** Possible values for FuncDef.flags.  Note that the _LENGTH and _TYPEOF
** values must correspond to OPFLAG_LENGTHARG and OPFLAG_TYPEOFARG.  And
** SQLITE_FUNC_CONSTANT must be the same as SQLITE_DETERMINISTIC.  There
** are assert() statements in the code to verify this.
*/
#define SQLITE_FUNC_ENCMASK  0x0003 /* SQLITE_UTF8, SQLITE_UTF16BE or UTF16LE */
#define SQLITE_FUNC_LIKE     0x0004 /* Candidate for the LIKE optimization */
#define SQLITE_FUNC_CASE     0x0008 /* Case-sensitive LIKE-type function */
#define SQLITE_FUNC_EPHEM    0x0010 /* Ephemeral.  Delete with VDBE */
#define SQLITE_FUNC_NEEDCOLL 0x0020 /* sqlite3GetFuncCollSeq() might be called*/

  Schema *pSchema;     /* Schema that contains this table */
  Table *pNextZombie;  /* Next on the Parse.pZombieTab list */
};

/*
** Allowed values for Table.tabFlags.
**
** TF_OOOHidden applies to tables or view that have hidden columns that are
** followed by non-hidden columns.  Example:  "CREATE VIRTUAL TABLE x USING
** vtab1(a HIDDEN, b);".  Since "b" is a non-hidden column but "a" is hidden,
** the TF_OOOHidden attribute would apply in this case.  Such tables require
** special handling during INSERT processing.
*/
#define TF_Readonly        0x01    /* Read-only system table */
#define TF_Ephemeral       0x02    /* An ephemeral table */

/*
** Test to see whether or not a table is a virtual table.  This is
** done as a macro so that it will be optimized out when virtual
** table support is omitted from the build.
*/
#ifndef SQLITE_OMIT_VIRTUALTABLE
#  define IsVirtual(X)      (((X)->tabFlags & TF_Virtual)!=0)

#else
#  define IsVirtual(X)      0
#endif

/*
** Macros to determine if a column is hidden.  IsOrdinaryHiddenColumn()
** only works for non-virtual tables (ordinary tables and views) and is
** always false unless SQLITE_ENABLE_HIDDEN_COLUMNS is defined.  The
** IsHiddenColumn() macro is general purpose.
*/
#if defined(SQLITE_ENABLE_HIDDEN_COLUMNS)
#  define IsHiddenColumn(X)         (((X)->colFlags & COLFLAG_HIDDEN)!=0)
#  define IsOrdinaryHiddenColumn(X) (((X)->colFlags & COLFLAG_HIDDEN)!=0)
#elif !defined(SQLITE_OMIT_VIRTUALTABLE)
#  define IsHiddenColumn(X)         (((X)->colFlags & COLFLAG_HIDDEN)!=0)
#  define IsOrdinaryHiddenColumn(X) 0
#else
#  define IsHiddenColumn(X)         0
#  define IsOrdinaryHiddenColumn(X) 0
#endif


/* Does the table have a rowid */
#define HasRowid(X)     (((X)->tabFlags & TF_WithoutRowid)==0)
#define VisibleRowid(X) (((X)->tabFlags & TF_NoVisibleRowid)==0)

/*
** Each foreign key constraint is an instance of the following structure.

  u16 nXField;        /* Number of columns beyond the key columns */
  sqlite3 *db;        /* The database connection */
  u8 *aSortOrder;     /* Sort order for each column. */
  CollSeq *aColl[1];  /* Collating sequence for each term of the key */
};

/*

** This object holds a record which has been parsed out into individual
** fields, for the purposes of doing a comparison.
**
** A record is an object that contains one or more fields of data.
** Records are used to store the content of a table row and to store
** the key of an index.  A blob encoding of a record is created by
** the OP_MakeRecord opcode of the VDBE and is disassembled by the
** OP_Column opcode.
**
** An instance of this object serves as a "key" for doing a search on
** an index b+tree. The goal of the search is to find the entry that
** is closed to the key described by this object.  This object might hold
** just a prefix of the key.  The number of fields is given by
** pKeyInfo->nField.
**
** The r1 and r2 fields are the values to return if this key is less than
** or greater than a key in the btree, respectively.  These are normally
** -1 and +1 respectively, but might be inverted to +1 and -1 if the b-tree
** is in DESC order.
**
** The key comparison functions actually return default_rc when they find
** an equals comparison.  default_rc can be -1, 0, or +1.  If there are
** multiple entries in the b-tree with the same key (when only looking
** at the first pKeyInfo->nFields,) then default_rc can be set to -1 to 
** cause the search to find the last match, or +1 to cause the search to
** find the first match.
**
** The key comparison functions will set eqSeen to true if they ever
** get and equal results when comparing this structure to a b-tree record.
** When default_rc!=0, the search might end up on the record immediately
** before the first match or immediately after the last match.  The
** eqSeen field will indicate whether or not an exact match exists in the
** b-tree.
*/
struct UnpackedRecord {
  KeyInfo *pKeyInfo;  /* Collation and sort-order information */
  Mem *aMem;          /* Values */
  u16 nField;         /* Number of entries in apMem[] */
  i8 default_rc;      /* Comparison result if keys are equal */
  u8 errCode;         /* Error detected by xRecordCompare (CORRUPT or NOMEM) */

  i8 r1;              /* Value to return if (lhs > rhs) */
  i8 r2;              /* Value to return if (rhs < lhs) */
  u8 eqSeen;          /* True if an equality comparison has been seen */
};


/*
** Each SQL index is represented in memory by an
** instance of the following structure.
**

#define SF_Values          0x0100  /* Synthesized from VALUES clause */
#define SF_MultiValue      0x0200  /* Single VALUES term with multiple rows */
#define SF_NestedFrom      0x0400  /* Part of a parenthesized FROM clause */
#define SF_MaybeConvert    0x0800  /* Need convertCompoundSelectToSubquery() */
#define SF_MinMaxAgg       0x1000  /* Aggregate containing min() or max() */
#define SF_Recursive       0x2000  /* The recursive part of a recursive CTE */
#define SF_Converted       0x4000  /* By convertCompoundSelectToSubquery() */
#define SF_IncludeHidden   0x8000  /* Include hidden columns in output */


/*
** The results of a SELECT can be distributed in several ways, as defined
** by one of the following macros.  The "SRT" prefix means "SELECT Result
** Type".
**

  ** using offsetof(Parse,nVar) so the nVar field must be the first field
  ** in the recursive region.
  ************************************************************************/

  int nVar;                 /* Number of '?' variables seen in the SQL so far */
  int nzVar;                /* Number of available slots in azVar[] */
  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 nAlias;               /* Number of aliased result set columns */
  int nHeight;              /* Expression tree height of current sub-select */

#ifndef SQLITE_OMIT_VIRTUALTABLE
  Token sArg;               /* Complete text of a module argument */
  Table **apVtabLock;       /* Pointer to virtual tables needing locking */
#endif
  Table *pZombieTab;        /* List of Table objects to delete after code gen */
  TriggerPrg *pTriggerPrg;  /* Linked list of coded triggers */
  With *pWith;              /* Current WITH clause, or NULL */
  With *pWithToFree;        /* Free this WITH object at the end of the parse */
};

/*
** Return true if currently inside an sqlite3_declare_vtab() call.
*/
#ifdef SQLITE_OMIT_VIRTUALTABLE
  #define IN_DECLARE_VTAB 0

#define OPFLAG_ISUPDATE      0x04    /* This OP_Insert is an sql UPDATE */
#define OPFLAG_APPEND        0x08    /* This is likely to be an append */
#define OPFLAG_USESEEKRESULT 0x10    /* Try to avoid a seek in BtreeInsert() */
#define OPFLAG_LENGTHARG     0x40    /* OP_Column only used for length() */
#define OPFLAG_TYPEOFARG     0x80    /* OP_Column only used for typeof() */
#define OPFLAG_BULKCSR       0x01    /* OP_Open** used to open bulk cursor */
#define OPFLAG_SEEKEQ        0x02    /* OP_Open** cursor uses EQ seek only */
#define OPFLAG_FORDELETE     0x08    /* OP_Open is opening for-delete csr */
#define OPFLAG_P2ISREG       0x10    /* P2 to OP_Open** is a register number */
#define OPFLAG_PERMUTE       0x01    /* OP_Compare: use the permutation */

/*
 * Each trigger present in the database schema is stored as an instance of
 * struct Trigger. 
 *
 * Pointers to instances of struct Trigger are stored in two ways.

  u8 eCode;                                 /* A small processing code */
  union {                                   /* Extra data for callback */
    NameContext *pNC;                          /* Naming context */
    int n;                                     /* A counter */
    int iCur;                                  /* A cursor number */
    SrcList *pSrcList;                         /* FROM clause */
    struct SrcCount *pSrcCount;                /* Counting column references */
    struct CCurHint *pCCurHint;                /* Used by codeCursorHint() */
  } u;
};

/* Forward declarations */
SQLITE_PRIVATE int sqlite3WalkExpr(Walker*, Expr*);
SQLITE_PRIVATE int sqlite3WalkExprList(Walker*, ExprList*);
SQLITE_PRIVATE int sqlite3WalkSelect(Walker*, Select*);
SQLITE_PRIVATE int sqlite3WalkSelectExpr(Walker*, Select*);
SQLITE_PRIVATE int sqlite3WalkSelectFrom(Walker*, Select*);
SQLITE_PRIVATE int sqlite3ExprWalkNoop(Walker*, Expr*);

/*
** Return code from the parse-tree walking primitives and their
** callbacks.
*/
#define WRC_Continue    0   /* Continue down into children */
#define WRC_Prune       1   /* Omit children but continue walking siblings */

#else
# define sqlite3MemoryBarrier()
#endif

SQLITE_PRIVATE sqlite3_int64 sqlite3StatusValue(int);
SQLITE_PRIVATE void sqlite3StatusUp(int, int);
SQLITE_PRIVATE void sqlite3StatusDown(int, int);
SQLITE_PRIVATE void sqlite3StatusHighwater(int, int);

/* Access to mutexes used by sqlite3_status() */
SQLITE_PRIVATE sqlite3_mutex *sqlite3Pcache1Mutex(void);
SQLITE_PRIVATE sqlite3_mutex *sqlite3MallocMutex(void);

#ifndef SQLITE_OMIT_FLOATING_POINT
SQLITE_PRIVATE   int sqlite3IsNaN(double);

SQLITE_PRIVATE   void *sqlite3TestTextToPtr(const char*);
#endif

#if defined(SQLITE_DEBUG)
SQLITE_PRIVATE   void sqlite3TreeViewExpr(TreeView*, const Expr*, u8);
SQLITE_PRIVATE   void sqlite3TreeViewExprList(TreeView*, const ExprList*, u8, const char*);
SQLITE_PRIVATE   void sqlite3TreeViewSelect(TreeView*, const Select*, u8);
SQLITE_PRIVATE   void sqlite3TreeViewWith(TreeView*, const With*, u8);
#endif


SQLITE_PRIVATE void sqlite3SetString(char **, sqlite3*, const char*);
SQLITE_PRIVATE void sqlite3ErrorMsg(Parse*, const char*, ...);
SQLITE_PRIVATE int sqlite3Dequote(char*);
SQLITE_PRIVATE int sqlite3KeywordCode(const unsigned char*, int);

SQLITE_PRIVATE void sqlite3DeleteColumnNames(sqlite3*,Table*);
SQLITE_PRIVATE int sqlite3ColumnsFromExprList(Parse*,ExprList*,i16*,Column**);
SQLITE_PRIVATE Table *sqlite3ResultSetOfSelect(Parse*,Select*);
SQLITE_PRIVATE void sqlite3OpenMasterTable(Parse *, int);
SQLITE_PRIVATE Index *sqlite3PrimaryKeyIndex(Table*);
SQLITE_PRIVATE i16 sqlite3ColumnOfIndex(Index*, i16);
SQLITE_PRIVATE void sqlite3StartTable(Parse*,Token*,Token*,int,int,int,int);
SQLITE_PRIVATE void sqlite3ColumnPropertiesFromName(Table*, Column*);
SQLITE_PRIVATE void sqlite3AddColumn(Parse*,Token*);
SQLITE_PRIVATE void sqlite3AddNotNull(Parse*, int);
SQLITE_PRIVATE void sqlite3AddPrimaryKey(Parse*, ExprList*, int, int, int);
SQLITE_PRIVATE void sqlite3AddCheckConstraint(Parse*, Expr*);
SQLITE_PRIVATE void sqlite3AddColumnType(Parse*,Token*);
SQLITE_PRIVATE void sqlite3AddDefaultValue(Parse*,ExprSpan*);
SQLITE_PRIVATE void sqlite3AddCollateType(Parse*, Token*);

SQLITE_PRIVATE int sqlite3WhereBreakLabel(WhereInfo*);
SQLITE_PRIVATE int sqlite3WhereOkOnePass(WhereInfo*, int*);
#define ONEPASS_OFF      0        /* Use of ONEPASS not allowed */
#define ONEPASS_SINGLE   1        /* ONEPASS valid for a single row update */
#define ONEPASS_MULTI    2        /* ONEPASS is valid for multiple rows */
SQLITE_PRIVATE void sqlite3ExprCodeLoadIndexColumn(Parse*, Index*, int, int, int);
SQLITE_PRIVATE int sqlite3ExprCodeGetColumn(Parse*, Table*, int, int, int, u8);
SQLITE_PRIVATE void sqlite3ExprCodeGetColumnToReg(Parse*, Table*, int, int, int);
SQLITE_PRIVATE void sqlite3ExprCodeGetColumnOfTable(Vdbe*, Table*, int, int, int);
SQLITE_PRIVATE void sqlite3ExprCodeMove(Parse*, int, int, int);
SQLITE_PRIVATE void sqlite3ExprCacheStore(Parse*, int, int, int);
SQLITE_PRIVATE void sqlite3ExprCachePush(Parse*);
SQLITE_PRIVATE void sqlite3ExprCachePop(Parse*);
SQLITE_PRIVATE void sqlite3ExprCacheRemove(Parse*, int, int);
SQLITE_PRIVATE void sqlite3ExprCacheClear(Parse*);

SQLITE_PRIVATE void sqlite3Savepoint(Parse*, int, Token*);
SQLITE_PRIVATE void sqlite3CloseSavepoints(sqlite3 *);
SQLITE_PRIVATE void sqlite3LeaveMutexAndCloseZombie(sqlite3*);
SQLITE_PRIVATE int sqlite3ExprIsConstant(Expr*);
SQLITE_PRIVATE int sqlite3ExprIsConstantNotJoin(Expr*);
SQLITE_PRIVATE int sqlite3ExprIsConstantOrFunction(Expr*, u8);
SQLITE_PRIVATE int sqlite3ExprIsTableConstant(Expr*,int);
#ifdef SQLITE_ENABLE_CURSOR_HINTS
SQLITE_PRIVATE int sqlite3ExprContainsSubquery(Expr*);
#endif
SQLITE_PRIVATE int sqlite3ExprIsInteger(Expr*, int*);
SQLITE_PRIVATE int sqlite3ExprCanBeNull(const Expr*);
SQLITE_PRIVATE int sqlite3ExprNeedsNoAffinityChange(const Expr*, char);
SQLITE_PRIVATE int sqlite3IsRowid(const char*);
SQLITE_PRIVATE void sqlite3GenerateRowDelete(
    Parse*,Table*,Trigger*,int,int,int,i16,u8,u8,u8,int);
SQLITE_PRIVATE void sqlite3GenerateRowIndexDelete(Parse*, Table*, int, int, int*, int);
SQLITE_PRIVATE int sqlite3GenerateIndexKey(Parse*, Index*, int, int, int, int*,Index*,int);
SQLITE_PRIVATE void sqlite3ResolvePartIdxLabel(Parse*,int);
SQLITE_PRIVATE void sqlite3GenerateConstraintChecks(Parse*,Table*,int*,int,int,int,int,
                                     u8,u8,int,int*);
SQLITE_PRIVATE void sqlite3CompleteInsertion(Parse*,Table*,int,int,int,int*,int,int,int);
SQLITE_PRIVATE int sqlite3OpenTableAndIndices(Parse*, Table*, int, u8, int, u8*, int*, int*);
SQLITE_PRIVATE void sqlite3BeginWriteOperation(Parse*, int, int);
SQLITE_PRIVATE void sqlite3MultiWrite(Parse*);
SQLITE_PRIVATE void sqlite3MayAbort(Parse*);
SQLITE_PRIVATE void sqlite3HaltConstraint(Parse*, int, int, char*, i8, u8);
SQLITE_PRIVATE void sqlite3UniqueConstraint(Parse*, int, Index*);
SQLITE_PRIVATE void sqlite3RowidConstraint(Parse*, int, Table*);
SQLITE_PRIVATE Expr *sqlite3ExprDup(sqlite3*,Expr*,int);

  "DEFAULT_MMAP_SIZE=" CTIMEOPT_VAL(SQLITE_DEFAULT_MMAP_SIZE),
#endif
#if SQLITE_DISABLE_DIRSYNC
  "DISABLE_DIRSYNC",
#endif
#if SQLITE_DISABLE_LFS
  "DISABLE_LFS",
#endif
#if SQLITE_ENABLE_8_3_NAMES
  "ENABLE_8_3_NAMES",
#endif
#if SQLITE_ENABLE_API_ARMOR
  "ENABLE_API_ARMOR",
#endif
#if SQLITE_ENABLE_ATOMIC_WRITE
  "ENABLE_ATOMIC_WRITE",
#endif

  "IGNORE_AFP_LOCK_ERRORS",
#endif
#if SQLITE_IGNORE_FLOCK_LOCK_ERRORS
  "IGNORE_FLOCK_LOCK_ERRORS",
#endif
#ifdef SQLITE_INT64_TYPE
  "INT64_TYPE",
#endif
#ifdef SQLITE_LIKE_DOESNT_MATCH_BLOBS
  "LIKE_DOESNT_MATCH_BLOBS",
#endif
#if SQLITE_LOCK_TRACE
  "LOCK_TRACE",
#endif
#if defined(SQLITE_MAX_MMAP_SIZE) && !defined(SQLITE_MAX_MMAP_SIZE_xc)
  "MAX_MMAP_SIZE=" CTIMEOPT_VAL(SQLITE_MAX_MMAP_SIZE),
#endif

** The maximum number of times that a statement will try to reparse
** itself before giving up and returning SQLITE_SCHEMA.
*/
#ifndef SQLITE_MAX_SCHEMA_RETRY
# define SQLITE_MAX_SCHEMA_RETRY 50
#endif

/*
** VDBE_DISPLAY_P4 is true or false depending on whether or not the
** "explain" P4 display logic is enabled.
*/
#if !defined(SQLITE_OMIT_EXPLAIN) || !defined(NDEBUG) \
     || defined(VDBE_PROFILE) || defined(SQLITE_DEBUG)
# define VDBE_DISPLAY_P4 1
#else
# define VDBE_DISPLAY_P4 0
#endif

/*
** SQL is translated into a sequence of instructions to be
** executed by a virtual machine.  Each instruction is an instance
** of the following structure.
*/
typedef struct VdbeOp Op;

/* Opaque type used by the explainer */
typedef struct Explain Explain;

/* Elements of the linked list at Vdbe.pAuxData */
typedef struct AuxData AuxData;

/* Types of VDBE cursors */
#define CURTYPE_BTREE       0
#define CURTYPE_SORTER      1
#define CURTYPE_VTAB        2
#define CURTYPE_PSEUDO      3

/*
** A VdbeCursor is an superclass (a wrapper) for various cursor objects:




**
**      * A b-tree cursor

**          -  In the main database or in an ephemeral database
**          -  On either an index or a table
**      * A sorter
**      * A virtual table

**      * A one-row "pseudotable" stored in a single register
*/
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 */
#endif



  Bool isEphemeral:1;   /* True for an ephemeral table */
  Bool useRandomRowid:1;/* Generate new record numbers semi-randomly */

  Bool isOrdered:1;     /* True if the underlying table is BTREE_UNORDERED */
  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 */
  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;
  Btree *pBt;           /* Separate file holding temporary table */
  KeyInfo *pKeyInfo;    /* Info about index keys needed by index cursors */
  int seekResult;       /* Result of previous sqlite3BtreeMoveto() */
  i64 seqCount;         /* Sequence counter */
  i64 movetoTarget;     /* Argument to the deferred sqlite3BtreeMoveto() */

#ifdef SQLITE_ENABLE_COLUMN_USED_MASK
  u64 maskUsed;         /* Mask of columns used by this cursor */
#endif

  /* Cached information about the header for the data record that the
  ** cursor is currently pointing to.  Only valid if cacheStatus matches
  ** Vdbe.cacheCtr.  Vdbe.cacheCtr will never take on the value of

void sqliteVdbePopStack(Vdbe*,int);
SQLITE_PRIVATE int sqlite3VdbeCursorMoveto(VdbeCursor*);
SQLITE_PRIVATE int sqlite3VdbeCursorRestore(VdbeCursor*);
#if defined(SQLITE_DEBUG) || defined(VDBE_PROFILE)
SQLITE_PRIVATE void sqlite3VdbePrintOp(FILE*, int, Op*);
#endif
SQLITE_PRIVATE u32 sqlite3VdbeSerialTypeLen(u32);
SQLITE_PRIVATE u8 sqlite3VdbeOneByteSerialTypeLen(u8);
SQLITE_PRIVATE u32 sqlite3VdbeSerialType(Mem*, int, u32*);
SQLITE_PRIVATE u32 sqlite3VdbeSerialPut(unsigned char*, Mem*, u32);
SQLITE_PRIVATE u32 sqlite3VdbeSerialGet(const unsigned char*, u32, Mem*);
SQLITE_PRIVATE void sqlite3VdbeDeleteAuxData(Vdbe*, int, int);

int sqlite2BtreeKeyCompare(BtCursor *, const void *, int, int, int *);
SQLITE_PRIVATE int sqlite3VdbeIdxKeyCompare(sqlite3*,VdbeCursor*,UnpackedRecord*,int*);
SQLITE_PRIVATE int sqlite3VdbeIdxRowid(sqlite3*, BtCursor*, i64*);

/************** End of vdbeInt.h *********************************************/
/************** Continuing where we left off in status.c *********************/

/*
** Variables in which to record status information.
*/


#if SQLITE_PTRSIZE>4
typedef sqlite3_int64 sqlite3StatValueType;

#else
typedef u32 sqlite3StatValueType;

#endif
typedef struct sqlite3StatType sqlite3StatType;
static SQLITE_WSD struct sqlite3StatType {
  sqlite3StatValueType nowValue[10];  /* Current value */
  sqlite3StatValueType mxValue[10];   /* Maximum value */
} sqlite3Stat = { {0,}, {0,} };

/*
** Elements of sqlite3Stat[] are protected by either the memory allocator
** mutex, or by the pcache1 mutex.  The following array determines which.
*/
static const char statMutex[] = {

  assert( sqlite3_mutex_held(statMutex[op] ? sqlite3Pcache1Mutex()
                                           : sqlite3MallocMutex()) );
  assert( op>=0 && op<ArraySize(wsdStat.nowValue) );
  wsdStat.nowValue[op] -= N;
}

/*
** Adjust the highwater mark if necessary.
** The caller must hold the appropriate mutex.
*/
SQLITE_PRIVATE void sqlite3StatusHighwater(int op, int X){
  sqlite3StatValueType newValue;
  wsdStatInit;
  assert( X>=0 );
  newValue = (sqlite3StatValueType)X;
  assert( op>=0 && op<ArraySize(wsdStat.nowValue) );
  assert( op>=0 && op<ArraySize(statMutex) );
  assert( sqlite3_mutex_held(statMutex[op] ? sqlite3Pcache1Mutex()
                                           : sqlite3MallocMutex()) );
  assert( op==SQLITE_STATUS_MALLOC_SIZE
          || op==SQLITE_STATUS_PAGECACHE_SIZE
          || op==SQLITE_STATUS_SCRATCH_SIZE
          || op==SQLITE_STATUS_PARSER_STACK );
  if( newValue>wsdStat.mxValue[op] ){
    wsdStat.mxValue[op] = newValue;
  }
}

/*
** Query status information.
*/
SQLITE_API int SQLITE_STDCALL sqlite3_status64(

          nByte += sqlite3GlobalConfig.m.xRoundup(sizeof(HashElem)) * (
              pSchema->tblHash.count 
            + pSchema->trigHash.count
            + pSchema->idxHash.count
            + pSchema->fkeyHash.count
          );
          nByte += sqlite3_msize(pSchema->tblHash.ht);
          nByte += sqlite3_msize(pSchema->trigHash.ht);
          nByte += sqlite3_msize(pSchema->idxHash.ht);
          nByte += sqlite3_msize(pSchema->fkeyHash.ht);

          for(p=sqliteHashFirst(&pSchema->trigHash); p; p=sqliteHashNext(p)){
            sqlite3DeleteTrigger(db, (Trigger*)sqliteHashData(p));
          }
          for(p=sqliteHashFirst(&pSchema->tblHash); p; p=sqliteHashNext(p)){
            sqlite3DeleteTable(db, (Table *)sqliteHashData(p));
          }

/*
** Report the allocated size of a prior return from xMalloc()
** or xRealloc().
*/
static int sqlite3MemSize(void *pPrior){
#ifdef SQLITE_MALLOCSIZE
  assert( pPrior!=0 );
  return (int)SQLITE_MALLOCSIZE(pPrior);
#else
  sqlite3_int64 *p;
  assert( pPrior!=0 );
  p = (sqlite3_int64*)pPrior;
  p--;
  return (int)p[0];
#endif
}

/*

/*
** Return the size of an outstanding allocation, in bytes.  The
** size returned omits the 8-byte header overhead.  This only
** works for chunks that are currently checked out.
*/
static int memsys3Size(void *p){
  Mem3Block *pBlock;
  assert( p!=0 );
  pBlock = (Mem3Block*)p;
  assert( (pBlock[-1].u.hdr.size4x&1)!=0 );
  return (pBlock[-1].u.hdr.size4x&~3)*2 - 4;
}

/*
** Round up a request size to the next valid allocation size.

/*
** Return the size of an outstanding allocation, in bytes.  The
** size returned omits the 8-byte header overhead.  This only
** works for chunks that are currently checked out.
*/
static int memsys5Size(void *p){
  int iSize, i;
  assert( p!=0 );
  i = (int)(((u8 *)p-mem5.zPool)/mem5.szAtom);
  assert( i>=0 && i<mem5.nBlock );
  iSize = mem5.szAtom * (1 << (mem5.aCtrl[i]&CTRL_LOGSIZE));

  return iSize;
}

/*
** Return a block of memory of at least nBytes in size.
** Return NULL if unable.  Return NULL if nBytes==0.
**

  ** power of two that we can represent using 32-bit signed integers.
  */
  if( nByte > 0x40000000 ){
    return 0;
  }

  /* Round nByte up to the next valid power of two */
  for(iFullSz=mem5.szAtom,iLogsize=0; iFullSz<nByte; iFullSz*=2,iLogsize++){}

  /* Make sure mem5.aiFreelist[iLogsize] contains at least one free
  ** block.  If not, then split a block of the next larger power of
  ** two in order to create a new free block of size iLogsize.
  */
  for(iBin=iLogsize; iBin<=LOGMAX && mem5.aiFreelist[iBin]<0; iBin++){}
  if( iBin>LOGMAX ){

#if SQLITE_MUTEX_NREF
  volatile int nRef;         /* Number of entrances */
  volatile pthread_t owner;  /* Thread that is within this mutex */
  int trace;                 /* True to trace changes */
#endif
};
#if SQLITE_MUTEX_NREF
#define SQLITE3_MUTEX_INITIALIZER {PTHREAD_MUTEX_INITIALIZER,0,0,(pthread_t)0,0}
#else
#define SQLITE3_MUTEX_INITIALIZER { PTHREAD_MUTEX_INITIALIZER }
#endif

/*
** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routine are
** intended for use only inside assert() statements.  On some platforms,

*/
SQLITE_PRIVATE int sqlite3MallocInit(void){
  int rc;
  if( sqlite3GlobalConfig.m.xMalloc==0 ){
    sqlite3MemSetDefault();
  }
  memset(&mem0, 0, sizeof(mem0));

  mem0.mutex = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MEM);

  if( sqlite3GlobalConfig.pScratch && sqlite3GlobalConfig.szScratch>=100
      && sqlite3GlobalConfig.nScratch>0 ){
    int i, n, sz;
    ScratchFreeslot *pSlot;
    sz = ROUNDDOWN8(sqlite3GlobalConfig.szScratch);
    sqlite3GlobalConfig.szScratch = sz;
    pSlot = (ScratchFreeslot*)sqlite3GlobalConfig.pScratch;

** lock is already held.
*/
static int mallocWithAlarm(int n, void **pp){
  int nFull;
  void *p;
  assert( sqlite3_mutex_held(mem0.mutex) );
  nFull = sqlite3GlobalConfig.m.xRoundup(n);
  sqlite3StatusHighwater(SQLITE_STATUS_MALLOC_SIZE, n);
  if( mem0.alarmThreshold>0 ){
    sqlite3_int64 nUsed = sqlite3StatusValue(SQLITE_STATUS_MEMORY_USED);
    if( nUsed >= mem0.alarmThreshold - nFull ){
      mem0.nearlyFull = 1;
      sqlite3MallocAlarm(nFull);
    }else{
      mem0.nearlyFull = 0;

** embedded processor.
*/
SQLITE_PRIVATE void *sqlite3ScratchMalloc(int n){
  void *p;
  assert( n>0 );

  sqlite3_mutex_enter(mem0.mutex);
  sqlite3StatusHighwater(SQLITE_STATUS_SCRATCH_SIZE, n);
  if( mem0.nScratchFree && sqlite3GlobalConfig.szScratch>=n ){
    p = mem0.pScratchFree;
    mem0.pScratchFree = mem0.pScratchFree->pNext;
    mem0.nScratchFree--;
    sqlite3StatusUp(SQLITE_STATUS_SCRATCH_USED, 1);
    sqlite3_mutex_leave(mem0.mutex);
  }else{

** sqlite3Malloc() or sqlite3_malloc().
*/
SQLITE_PRIVATE int sqlite3MallocSize(void *p){
  assert( sqlite3MemdebugHasType(p, MEMTYPE_HEAP) );
  return sqlite3GlobalConfig.m.xSize(p);
}
SQLITE_PRIVATE int sqlite3DbMallocSize(sqlite3 *db, void *p){
  assert( p!=0 );
  if( db==0 || !isLookaside(db,p) ){
#if SQLITE_DEBUG
    if( db==0 ){
      assert( sqlite3MemdebugNoType(p, (u8)~MEMTYPE_HEAP) );
      assert( sqlite3MemdebugHasType(p, MEMTYPE_HEAP) );
    }else{
      assert( sqlite3MemdebugHasType(p, (MEMTYPE_LOOKASIDE|MEMTYPE_HEAP)) );
      assert( sqlite3MemdebugNoType(p, (u8)~(MEMTYPE_LOOKASIDE|MEMTYPE_HEAP)) );
    }
#endif
    return sqlite3GlobalConfig.m.xSize(p);
  }else{
    assert( sqlite3_mutex_held(db->mutex) );
    return db->lookaside.sz;
  }
}
SQLITE_API sqlite3_uint64 SQLITE_STDCALL sqlite3_msize(void *p){
  assert( sqlite3MemdebugNoType(p, (u8)~MEMTYPE_HEAP) );
  assert( sqlite3MemdebugHasType(p, MEMTYPE_HEAP) );
  return p ? sqlite3GlobalConfig.m.xSize(p) : 0;
}

/*
** Free memory previously obtained from sqlite3Malloc().
*/
SQLITE_API void SQLITE_STDCALL sqlite3_free(void *p){
  if( p==0 ) return;  /* IMP: R-49053-54554 */

  ** argument to xRealloc is always a value returned by a prior call to
  ** xRoundup. */
  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( sqlite3StatusValue(SQLITE_STATUS_MEMORY_USED) >= 
          mem0.alarmThreshold-nDiff ){
      sqlite3MallocAlarm(nDiff);
    }
    pNew = sqlite3GlobalConfig.m.xRealloc(pOld, nNew);
    if( pNew==0 && mem0.alarmThreshold>0 ){

      while( c>='0' && c<='9' ){
        wx = wx*10 + c - '0';
        c = *++fmt;
      }
      testcase( wx>0x7fffffff );
      width = wx & 0x7fffffff;
    }
    assert( width>=0 );
#ifdef SQLITE_PRINTF_PRECISION_LIMIT
    if( width>SQLITE_PRINTF_PRECISION_LIMIT ){
      width = SQLITE_PRINTF_PRECISION_LIMIT;
    }
#endif

    /* Get the precision */
    if( c=='.' ){
      c = *++fmt;
      if( c=='*' ){
        if( bArgList ){
          precision = (int)getIntArg(pArgList);

        }
        testcase( px>0x7fffffff );
        precision = px & 0x7fffffff;
      }
    }else{
      precision = -1;
    }
    assert( precision>=(-1) );
#ifdef SQLITE_PRINTF_PRECISION_LIMIT
    if( precision>SQLITE_PRINTF_PRECISION_LIMIT ){
      precision = SQLITE_PRINTF_PRECISION_LIMIT;
    }
#endif


    /* Get the conversion type modifier */
    if( c=='l' ){
      flag_long = 1;
      c = *++fmt;
      if( c=='l' ){
        flag_longlong = 1;
        c = *++fmt;

    */
    width -= length;
    if( width>0 && !flag_leftjustify ) sqlite3AppendChar(pAccum, width, ' ');
    sqlite3StrAccumAppend(pAccum, bufpt, length);
    if( width>0 && flag_leftjustify ) sqlite3AppendChar(pAccum, width, ' ');

    if( zExtra ){
      sqlite3DbFree(pAccum->db, zExtra);
      zExtra = 0;
    }
  }/* End for loop over the format string */
} /* End of function */

/*
** Enlarge the memory allocation on a StrAccum object so that it is

** Shorthand for starting a new tree item that consists of a single label
*/
static void sqlite3TreeViewItem(TreeView *p, const char *zLabel,u8 moreFollows){
  p = sqlite3TreeViewPush(p, moreFollows);
  sqlite3TreeViewLine(p, "%s", zLabel);
}

/*
** Generate a human-readable description of a WITH clause.
*/
SQLITE_PRIVATE void sqlite3TreeViewWith(TreeView *pView, const With *pWith, u8 moreToFollow){
  int i;
  if( pWith==0 ) return;
  if( pWith->nCte==0 ) return;
  if( pWith->pOuter ){
    sqlite3TreeViewLine(pView, "WITH (0x%p, pOuter=0x%p)",pWith,pWith->pOuter);
  }else{
    sqlite3TreeViewLine(pView, "WITH (0x%p)", pWith);
  }
  if( pWith->nCte>0 ){
    pView = sqlite3TreeViewPush(pView, 1);
    for(i=0; i<pWith->nCte; i++){
      StrAccum x;
      char zLine[1000];
      const struct Cte *pCte = &pWith->a[i];
      sqlite3StrAccumInit(&x, 0, zLine, sizeof(zLine), 0);
      sqlite3XPrintf(&x, 0, "%s", pCte->zName);
      if( pCte->pCols && pCte->pCols->nExpr>0 ){
        char cSep = '(';
        int j;
        for(j=0; j<pCte->pCols->nExpr; j++){
          sqlite3XPrintf(&x, 0, "%c%s", cSep, pCte->pCols->a[j].zName);
          cSep = ',';
        }
        sqlite3XPrintf(&x, 0, ")");
      }
      sqlite3XPrintf(&x, 0, " AS");
      sqlite3StrAccumFinish(&x);
      sqlite3TreeViewItem(pView, zLine, i<pWith->nCte-1);
      sqlite3TreeViewSelect(pView, pCte->pSelect, 0);
      sqlite3TreeViewPop(pView);
    }
    sqlite3TreeViewPop(pView);
  }
}


/*
** Generate a human-readable description of a the Select object.
*/
SQLITE_PRIVATE void sqlite3TreeViewSelect(TreeView *pView, const Select *p, u8 moreToFollow){
  int n = 0;
  int cnt = 0;
  pView = sqlite3TreeViewPush(pView, moreToFollow);
  if( p->pWith ){
    sqlite3TreeViewWith(pView, p->pWith, 1);
    cnt = 1;
    sqlite3TreeViewPush(pView, 1);
  }
  do{
    sqlite3TreeViewLine(pView, "SELECT%s%s (0x%p) selFlags=0x%x",
      ((p->selFlags & SF_Distinct) ? " DISTINCT" : ""),
      ((p->selFlags & SF_Aggregate) ? " agg_flag" : ""), p, p->selFlags
    );
    if( cnt++ ) sqlite3TreeViewPop(pView);
    if( p->pPrior ){

    *pNum = -(i64)u;
  }else{
    *pNum = (i64)u;
  }
  testcase( i==18 );
  testcase( i==19 );
  testcase( i==20 );
  if( (c!=0 && &zNum[i]<zEnd) || (i==0 && zStart==zNum)
       || i>19*incr || nonNum ){
    /* zNum is empty or contains non-numeric text or is longer
    ** than 19 digits (thus guaranteeing that it is too large) */
    return 1;
  }else if( i<19*incr ){
    /* Less than 19 digits, so we know that it fits in 64 bits */
    assert( u<=LARGEST_INT64 );
    return 0;

  p++;
  a = a<<14;
  a |= *p;
  /* a: p0<<28 | p2<<14 | p4 (unmasked) */
  if (!(a&0x80))
  {
    /* we can skip these cause they were (effectively) done above
    ** while calculating s */
    /* a &= (0x7f<<28)|(0x7f<<14)|(0x7f); */
    /* b &= (0x7f<<14)|(0x7f); */
    b = b<<7;
    a |= b;
    s = s>>18;
    *v = ((u64)s)<<32 | a;
    return 5;

  insertElement(pH, pH->ht ? &pH->ht[h] : 0, new_elem);
  return 0;
}

/************** End of hash.c ************************************************/
/************** Begin file opcodes.c *****************************************/
/* Automatically generated.  Do not edit */
/* See the tool/mkopcodec.tcl script for details. */
#if !defined(SQLITE_OMIT_EXPLAIN) \
 || defined(VDBE_PROFILE) \
 || defined(SQLITE_DEBUG)
#if defined(SQLITE_ENABLE_EXPLAIN_COMMENTS) || defined(SQLITE_DEBUG)
# define OpHelp(X) "\0" X
#else
# define OpHelp(X)
#endif
SQLITE_PRIVATE const char *sqlite3OpcodeName(int i){
 static const char *const azName[] = { "?",
    /*   1 */ "Savepoint"        OpHelp(""),
    /*   2 */ "AutoCommit"       OpHelp(""),
    /*   3 */ "Transaction"      OpHelp(""),
    /*   4 */ "SorterNext"       OpHelp(""),
    /*   5 */ "PrevIfOpen"       OpHelp(""),
    /*   6 */ "NextIfOpen"       OpHelp(""),
    /*   7 */ "Prev"             OpHelp(""),
    /*   8 */ "Next"             OpHelp(""),
    /*   9 */ "Checkpoint"       OpHelp(""),
    /*  10 */ "JournalMode"      OpHelp(""),
    /*  11 */ "Vacuum"           OpHelp(""),
    /*  12 */ "VFilter"          OpHelp("iplan=r[P3] zplan='P4'"),
    /*  13 */ "VUpdate"          OpHelp("data=r[P3@P2]"),
    /*  14 */ "Goto"             OpHelp(""),
    /*  15 */ "Gosub"            OpHelp(""),
    /*  16 */ "Return"           OpHelp(""),
    /*  17 */ "InitCoroutine"    OpHelp(""),
    /*  18 */ "EndCoroutine"     OpHelp(""),
    /*  19 */ "Not"              OpHelp("r[P2]= !r[P1]"),
    /*  20 */ "Yield"            OpHelp(""),
    /*  21 */ "HaltIfNull"       OpHelp("if r[P3]=null halt"),
    /*  22 */ "Halt"             OpHelp(""),
    /*  23 */ "Integer"          OpHelp("r[P2]=P1"),
    /*  24 */ "Int64"            OpHelp("r[P2]=P4"),
    /*  25 */ "String"           OpHelp("r[P2]='P4' (len=P1)"),
    /*  26 */ "Null"             OpHelp("r[P2..P3]=NULL"),
    /*  27 */ "SoftNull"         OpHelp("r[P1]=NULL"),
    /*  28 */ "Blob"             OpHelp("r[P2]=P4 (len=P1)"),
    /*  29 */ "Variable"         OpHelp("r[P2]=parameter(P1,P4)"),
    /*  30 */ "Move"             OpHelp("r[P2@P3]=r[P1@P3]"),
    /*  31 */ "Copy"             OpHelp("r[P2@P3+1]=r[P1@P3+1]"),
    /*  32 */ "SCopy"            OpHelp("r[P2]=r[P1]"),
    /*  33 */ "IntCopy"          OpHelp("r[P2]=r[P1]"),
    /*  34 */ "ResultRow"        OpHelp("output=r[P1@P2]"),
    /*  35 */ "CollSeq"          OpHelp(""),
    /*  36 */ "Function0"        OpHelp("r[P3]=func(r[P2@P5])"),
    /*  37 */ "Function"         OpHelp("r[P3]=func(r[P2@P5])"),
    /*  38 */ "AddImm"           OpHelp("r[P1]=r[P1]+P2"),
    /*  39 */ "MustBeInt"        OpHelp(""),
    /*  40 */ "RealAffinity"     OpHelp(""),
    /*  41 */ "Cast"             OpHelp("affinity(r[P1])"),
    /*  42 */ "Permutation"      OpHelp(""),
    /*  43 */ "Compare"          OpHelp("r[P1@P3] <-> r[P2@P3]"),
    /*  44 */ "Jump"             OpHelp(""),
    /*  45 */ "Once"             OpHelp(""),
    /*  46 */ "If"               OpHelp(""),
    /*  47 */ "IfNot"            OpHelp(""),
    /*  48 */ "Column"           OpHelp("r[P3]=PX"),
    /*  49 */ "Affinity"         OpHelp("affinity(r[P1@P2])"),
    /*  50 */ "MakeRecord"       OpHelp("r[P3]=mkrec(r[P1@P2])"),
    /*  51 */ "Count"            OpHelp("r[P2]=count()"),
    /*  52 */ "ReadCookie"       OpHelp(""),
    /*  53 */ "SetCookie"        OpHelp(""),
    /*  54 */ "ReopenIdx"        OpHelp("root=P2 iDb=P3"),
    /*  55 */ "OpenRead"         OpHelp("root=P2 iDb=P3"),
    /*  56 */ "OpenWrite"        OpHelp("root=P2 iDb=P3"),
    /*  57 */ "OpenAutoindex"    OpHelp("nColumn=P2"),
    /*  58 */ "OpenEphemeral"    OpHelp("nColumn=P2"),
    /*  59 */ "SorterOpen"       OpHelp(""),
    /*  60 */ "SequenceTest"     OpHelp("if( cursor[P1].ctr++ ) pc = P2"),
    /*  61 */ "OpenPseudo"       OpHelp("P3 columns in r[P2]"),
    /*  62 */ "Close"            OpHelp(""),
    /*  63 */ "ColumnsUsed"      OpHelp(""),
    /*  64 */ "SeekLT"           OpHelp("key=r[P3@P4]"),
    /*  65 */ "SeekLE"           OpHelp("key=r[P3@P4]"),
    /*  66 */ "SeekGE"           OpHelp("key=r[P3@P4]"),
    /*  67 */ "SeekGT"           OpHelp("key=r[P3@P4]"),
    /*  68 */ "Seek"             OpHelp("intkey=r[P2]"),
    /*  69 */ "NoConflict"       OpHelp("key=r[P3@P4]"),
    /*  70 */ "NotFound"         OpHelp("key=r[P3@P4]"),

    /*  71 */ "Or"               OpHelp("r[P3]=(r[P1] || r[P2])"),
    /*  72 */ "And"              OpHelp("r[P3]=(r[P1] && r[P2])"),
    /*  73 */ "Found"            OpHelp("key=r[P3@P4]"),
    /*  74 */ "NotExists"        OpHelp("intkey=r[P3]"),
    /*  75 */ "Sequence"         OpHelp("r[P2]=cursor[P1].ctr++"),

    /*  76 */ "IsNull"           OpHelp("if r[P1]==NULL goto P2"),
    /*  77 */ "NotNull"          OpHelp("if r[P1]!=NULL goto P2"),
    /*  78 */ "Ne"               OpHelp("if r[P1]!=r[P3] goto P2"),
    /*  79 */ "Eq"               OpHelp("if r[P1]==r[P3] goto P2"),
    /*  80 */ "Gt"               OpHelp("if r[P1]>r[P3] goto P2"),
    /*  81 */ "Le"               OpHelp("if r[P1]<=r[P3] goto P2"),
    /*  82 */ "Lt"               OpHelp("if r[P1]<r[P3] goto P2"),
    /*  83 */ "Ge"               OpHelp("if r[P1]>=r[P3] goto P2"),
    /*  84 */ "NewRowid"         OpHelp("r[P2]=rowid"),
    /*  85 */ "BitAnd"           OpHelp("r[P3]=r[P1]&r[P2]"),
    /*  86 */ "BitOr"            OpHelp("r[P3]=r[P1]|r[P2]"),
    /*  87 */ "ShiftLeft"        OpHelp("r[P3]=r[P2]<<r[P1]"),
    /*  88 */ "ShiftRight"       OpHelp("r[P3]=r[P2]>>r[P1]"),
    /*  89 */ "Add"              OpHelp("r[P3]=r[P1]+r[P2]"),
    /*  90 */ "Subtract"         OpHelp("r[P3]=r[P2]-r[P1]"),
    /*  91 */ "Multiply"         OpHelp("r[P3]=r[P1]*r[P2]"),
    /*  92 */ "Divide"           OpHelp("r[P3]=r[P2]/r[P1]"),
    /*  93 */ "Remainder"        OpHelp("r[P3]=r[P2]%r[P1]"),
    /*  94 */ "Concat"           OpHelp("r[P3]=r[P2]+r[P1]"),
    /*  95 */ "Insert"           OpHelp("intkey=r[P3] data=r[P2]"),
    /*  96 */ "BitNot"           OpHelp("r[P1]= ~r[P1]"),
    /*  97 */ "String8"          OpHelp("r[P2]='P4'"),
    /*  98 */ "InsertInt"        OpHelp("intkey=P3 data=r[P2]"),
    /*  99 */ "Delete"           OpHelp(""),
    /* 100 */ "ResetCount"       OpHelp(""),
    /* 101 */ "SorterCompare"    OpHelp("if key(P1)!=trim(r[P3],P4) goto P2"),
    /* 102 */ "SorterData"       OpHelp("r[P2]=data"),
    /* 103 */ "RowKey"           OpHelp("r[P2]=key"),
    /* 104 */ "RowData"          OpHelp("r[P2]=data"),
    /* 105 */ "Rowid"            OpHelp("r[P2]=rowid"),
    /* 106 */ "NullRow"          OpHelp(""),
    /* 107 */ "Last"             OpHelp(""),
    /* 108 */ "SorterSort"       OpHelp(""),
    /* 109 */ "Sort"             OpHelp(""),
    /* 110 */ "Rewind"           OpHelp(""),
    /* 111 */ "SorterInsert"     OpHelp(""),
    /* 112 */ "IdxInsert"        OpHelp("key=r[P2]"),
    /* 113 */ "IdxDelete"        OpHelp("key=r[P2@P3]"),
    /* 114 */ "IdxRowid"         OpHelp("r[P2]=rowid"),
    /* 115 */ "IdxLE"            OpHelp("key=r[P3@P4]"),
    /* 116 */ "IdxGT"            OpHelp("key=r[P3@P4]"),
    /* 117 */ "IdxLT"            OpHelp("key=r[P3@P4]"),
    /* 118 */ "IdxGE"            OpHelp("key=r[P3@P4]"),
    /* 119 */ "Destroy"          OpHelp(""),
    /* 120 */ "Clear"            OpHelp(""),
    /* 121 */ "ResetSorter"      OpHelp(""),
    /* 122 */ "CreateIndex"      OpHelp("r[P2]=root iDb=P1"),
    /* 123 */ "CreateTable"      OpHelp("r[P2]=root iDb=P1"),
    /* 124 */ "ParseSchema"      OpHelp(""),
    /* 125 */ "LoadAnalysis"     OpHelp(""),
    /* 126 */ "DropTable"        OpHelp(""),
    /* 127 */ "DropIndex"        OpHelp(""),
    /* 128 */ "DropTrigger"      OpHelp(""),
    /* 129 */ "IntegrityCk"      OpHelp(""),
    /* 130 */ "RowSetAdd"        OpHelp("rowset(P1)=r[P2]"),
    /* 131 */ "RowSetRead"       OpHelp("r[P3]=rowset(P1)"),
    /* 132 */ "RowSetTest"       OpHelp("if r[P3] in rowset(P1) goto P2"),

    /* 133 */ "Real"             OpHelp("r[P2]=P4"),
    /* 134 */ "Program"          OpHelp(""),
    /* 135 */ "Param"            OpHelp(""),
    /* 136 */ "FkCounter"        OpHelp("fkctr[P1]+=P2"),
    /* 137 */ "FkIfZero"         OpHelp("if fkctr[P1]==0 goto P2"),
    /* 138 */ "MemMax"           OpHelp("r[P1]=max(r[P1],r[P2])"),
    /* 139 */ "IfPos"            OpHelp("if r[P1]>0 then r[P1]-=P3, goto P2"),
    /* 140 */ "SetIfNotPos"      OpHelp("if r[P1]<=0 then r[P2]=P3"),
    /* 141 */ "IfNotZero"        OpHelp("if r[P1]!=0 then r[P1]-=P3, goto P2"),
    /* 142 */ "DecrJumpZero"     OpHelp("if (--r[P1])==0 goto P2"),
    /* 143 */ "JumpZeroIncr"     OpHelp("if (r[P1]++)==0 ) goto P2"),
    /* 144 */ "AggStep0"         OpHelp("accum=r[P3] step(r[P2@P5])"),
    /* 145 */ "AggStep"          OpHelp("accum=r[P3] step(r[P2@P5])"),
    /* 146 */ "AggFinal"         OpHelp("accum=r[P1] N=P2"),
    /* 147 */ "IncrVacuum"       OpHelp(""),
    /* 148 */ "Expire"           OpHelp(""),
    /* 149 */ "TableLock"        OpHelp("iDb=P1 root=P2 write=P3"),
    /* 150 */ "VBegin"           OpHelp(""),
    /* 151 */ "VCreate"          OpHelp(""),
    /* 152 */ "VDestroy"         OpHelp(""),
    /* 153 */ "VOpen"            OpHelp(""),
    /* 154 */ "VColumn"          OpHelp("r[P3]=vcolumn(P2)"),
    /* 155 */ "VNext"            OpHelp(""),
    /* 156 */ "VRename"          OpHelp(""),
    /* 157 */ "Pagecount"        OpHelp(""),
    /* 158 */ "MaxPgcnt"         OpHelp(""),
    /* 159 */ "Init"             OpHelp("Start at P2"),
    /* 160 */ "CursorHint"       OpHelp(""),
    /* 161 */ "Noop"             OpHelp(""),
    /* 162 */ "Explain"          OpHelp(""),
  };
  return azName[i];
}
#endif

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

#else
# define UNIXFILE_DIRSYNC    0x00
#endif
#define UNIXFILE_PSOW        0x10     /* SQLITE_IOCAP_POWERSAFE_OVERWRITE */
#define UNIXFILE_DELETE      0x20     /* Delete on close */
#define UNIXFILE_URI         0x40     /* Filename might have query parameters */
#define UNIXFILE_NOLOCK      0x80     /* Do no file locking */



/*
** Include code that is common to all os_*.c files
*/
/************** Include os_common.h in the middle of os_unix.c ***************/
/************** Begin file os_common.h ***************************************/
/*

** The safest way to deal with the problem is to always use this wrapper
** which always has the same well-defined interface.
*/
static int posixOpen(const char *zFile, int flags, int mode){
  return open(zFile, flags, mode);
}














/* Forward reference */
static int openDirectory(const char*, int*);
static int unixGetpagesize(void);

/*
** Many system calls are accessed through pointer-to-functions so that
** they may be overridden at runtime to facilitate fault injection during

  { "pwrite64",     (sqlite3_syscall_ptr)pwrite64,   0  },
#else
  { "pwrite64",     (sqlite3_syscall_ptr)0,          0  },
#endif
#define osPwrite64  ((ssize_t(*)(int,const void*,size_t,off_t))\
                    aSyscall[13].pCurrent)

  { "fchmod",       (sqlite3_syscall_ptr)fchmod,          0  },
#define osFchmod    ((int(*)(int,mode_t))aSyscall[14].pCurrent)

#if defined(HAVE_POSIX_FALLOCATE) && HAVE_POSIX_FALLOCATE
  { "fallocate",    (sqlite3_syscall_ptr)posix_fallocate,  0 },
#else
  { "fallocate",    (sqlite3_syscall_ptr)0,                0 },
#endif

  { "mkdir",        (sqlite3_syscall_ptr)mkdir,           0 },
#define osMkdir     ((int(*)(const char*,mode_t))aSyscall[18].pCurrent)

  { "rmdir",        (sqlite3_syscall_ptr)rmdir,           0 },
#define osRmdir     ((int(*)(const char*))aSyscall[19].pCurrent)

  { "fchown",       (sqlite3_syscall_ptr)fchown,          0 },
#define osFchown    ((int(*)(int,uid_t,gid_t))aSyscall[20].pCurrent)

  { "geteuid",      (sqlite3_syscall_ptr)geteuid,         0 },
#define osGeteuid   ((uid_t(*)(void))aSyscall[21].pCurrent)

#if !defined(SQLITE_OMIT_WAL) || SQLITE_MAX_MMAP_SIZE>0
  { "mmap",       (sqlite3_syscall_ptr)mmap,     0 },
#define osMmap ((void*(*)(void*,size_t,int,int,int,off_t))aSyscall[22].pCurrent)

  { "munmap",       (sqlite3_syscall_ptr)munmap,          0 },
#define osMunmap ((void*(*)(void*,size_t))aSyscall[23].pCurrent)

#if HAVE_MREMAP
  { "mremap",       (sqlite3_syscall_ptr)mremap,          0 },
#else
  { "mremap",       (sqlite3_syscall_ptr)0,               0 },
#endif
#define osMremap ((void*(*)(void*,size_t,size_t,int,...))aSyscall[24].pCurrent)

  { "getpagesize",  (sqlite3_syscall_ptr)unixGetpagesize, 0 },
#define osGetpagesize ((int(*)(void))aSyscall[25].pCurrent)

  { "readlink",     (sqlite3_syscall_ptr)readlink,        0 },
#define osReadlink ((ssize_t(*)(const char*,char*,size_t))aSyscall[26].pCurrent)

#endif

}; /* End of the overrideable system calls */


/*
** On some systems, calls to fchown() will trigger a message in a security
** log if they come from non-root processes.  So avoid calling fchown() if
** we are not running as root.
*/
static int robustFchown(int fd, uid_t uid, gid_t gid){
#if OS_VXWORKS
  return 0;
#else
  return osGeteuid() ? 0 : osFchown(fd,uid,gid);
#endif
}

/*
** This is the xSetSystemCall() method of sqlite3_vfs for all of the
** "unix" VFSes.  Return SQLITE_OK opon successfully updating the
** system call pointer, or SQLITE_NOTFOUND if there is no configurable
** system call named zName.
*/
static int unixSetSystemCall(

** and a variety of "please close the file descriptor NOW" errors into 
** SQLITE_IOERR
** 
** Errors during initialization of locks, or file system support for locks,
** should handle ENOLCK, ENOTSUP, EOPNOTSUPP separately.
*/
static int sqliteErrorFromPosixError(int posixError, int sqliteIOErr) {
  assert( (sqliteIOErr == SQLITE_IOERR_LOCK) || 
          (sqliteIOErr == SQLITE_IOERR_UNLOCK) || 
          (sqliteIOErr == SQLITE_IOERR_RDLOCK) ||
          (sqliteIOErr == SQLITE_IOERR_CHECKRESERVEDLOCK) );
  switch (posixError) {












  case EACCES: 



  case EAGAIN:
  case ETIMEDOUT:
  case EBUSY:
  case EINTR:
  case ENOLCK:  
    /* random NFS retry error, unless during file system support 
     * introspection, in which it actually means what it says */
    return SQLITE_BUSY;
    









  case EPERM: 
    return SQLITE_PERM;
    























  default: 
    return sqliteIOErr;
  }
}


/******************************************************************************

/*
** A lists of all unixInodeInfo objects.
*/
static unixInodeInfo *inodeList = 0;

/*
**
** This function - unixLogErrorAtLine(), is only ever called via the macro
** unixLogError().
**
** It is invoked after an error occurs in an OS function and errno has been
** set. It logs a message using sqlite3_log() containing the current value of
** errno and, if possible, the human-readable equivalent from strerror() or
** strerror_r().
**

  /* Get low-level information about the file that we can used to
  ** create a unique name for the file.
  */
  fd = pFile->h;
  rc = osFstat(fd, &statbuf);
  if( rc!=0 ){
    storeLastErrno(pFile, errno);
#if defined(EOVERFLOW) && defined(SQLITE_DISABLE_LFS)
    if( pFile->lastErrno==EOVERFLOW ) return SQLITE_NOLFS;
#endif
    return SQLITE_IOERR;
  }

#ifdef __APPLE__
  /* On OS X on an msdos filesystem, the inode number is reported

** (3) The file has not been renamed or unlinked
**
** Issue sqlite3_log(SQLITE_WARNING,...) messages if anything is not right.
*/
static void verifyDbFile(unixFile *pFile){
  struct stat buf;
  int rc;





  rc = osFstat(pFile->h, &buf);
  if( rc!=0 ){
    sqlite3_log(SQLITE_WARNING, "cannot fstat db file %s", pFile->zPath);

    return;
  }
  if( buf.st_nlink==0 && (pFile->ctrlFlags & UNIXFILE_DELETE)==0 ){
    sqlite3_log(SQLITE_WARNING, "file unlinked while open: %s", pFile->zPath);

    return;
  }
  if( buf.st_nlink>1 ){
    sqlite3_log(SQLITE_WARNING, "multiple links to file: %s", pFile->zPath);

    return;
  }
  if( fileHasMoved(pFile) ){
    sqlite3_log(SQLITE_WARNING, "file renamed while open: %s", pFile->zPath);

    return;
  }
}


/*
** This routine checks if there is a RESERVED lock held on the specified
** file by this or any other process. If such a lock is held, set *pResOut
** to a non-zero value otherwise *pResOut is set to zero.  The return value
** is set to SQLITE_OK unless an I/O error occurs during lock checking.
*/
static int unixCheckReservedLock(sqlite3_file *id, int *pResOut){
  int rc = SQLITE_OK;
  int reserved = 0;
  unixFile *pFile = (unixFile*)id;

  SimulateIOError( return SQLITE_IOERR_CHECKRESERVEDLOCK; );

  assert( pFile );
  assert( pFile->eFileLock<=SHARED_LOCK );
  unixEnterMutex(); /* Because pFile->pInode is shared across threads */

  /* Check if a thread in this process holds such a lock */
  if( pFile->pInode->eFileLock>SHARED_LOCK ){
    reserved = 1;
  }

** to fcntl() fails. In this case, errno is set appropriately (by fcntl()).
*/
static int unixFileLock(unixFile *pFile, struct flock *pLock){
  int rc;
  unixInodeInfo *pInode = pFile->pInode;
  assert( unixMutexHeld() );
  assert( pInode!=0 );

  if( (pFile->ctrlFlags & (UNIXFILE_EXCL|UNIXFILE_RDONLY))==UNIXFILE_EXCL ){

    if( pInode->bProcessLock==0 ){
      struct flock lock;
      assert( pInode->nLock==0 );
      lock.l_whence = SEEK_SET;
      lock.l_start = SHARED_FIRST;
      lock.l_len = SHARED_SIZE;
      lock.l_type = F_WRLCK;

        lock.l_type = F_UNLCK;
        lock.l_whence = SEEK_SET;
        lock.l_start = SHARED_FIRST;
        lock.l_len = divSize;
        if( unixFileLock(pFile, &lock)==(-1) ){
          tErrno = errno;
          rc = SQLITE_IOERR_UNLOCK;

          storeLastErrno(pFile, tErrno);

          goto end_unlock;
        }
        lock.l_type = F_RDLCK;
        lock.l_whence = SEEK_SET;
        lock.l_start = SHARED_FIRST;
        lock.l_len = divSize;
        if( unixFileLock(pFile, &lock)==(-1) ){

        lock.l_type = F_UNLCK;
        lock.l_whence = SEEK_SET;
        lock.l_start = SHARED_FIRST+divSize;
        lock.l_len = SHARED_SIZE-divSize;
        if( unixFileLock(pFile, &lock)==(-1) ){
          tErrno = errno;
          rc = SQLITE_IOERR_UNLOCK;

          storeLastErrno(pFile, tErrno);

          goto end_unlock;
        }
      }else
#endif /* defined(__APPLE__) && SQLITE_ENABLE_LOCKING_STYLE */
      {
        lock.l_type = F_RDLCK;
        lock.l_whence = SEEK_SET;

  int rc = SQLITE_OK;
  int reserved = 0;
  unixFile *pFile = (unixFile*)id;

  SimulateIOError( return SQLITE_IOERR_CHECKRESERVEDLOCK; );
  
  assert( pFile );









  reserved = osAccess((const char*)pFile->lockingContext, 0)==0;

  OSTRACE(("TEST WR-LOCK %d %d %d (dotlock)\n", pFile->h, rc, reserved));
  *pResOut = reserved;
  return rc;
}

/*
** Lock the file with the lock specified by parameter eFileLock - one

  if( rc<0 ){
    /* failed to open/create the lock directory */
    int tErrno = errno;
    if( EEXIST == tErrno ){
      rc = SQLITE_BUSY;
    } else {
      rc = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_LOCK);
      if( rc!=SQLITE_BUSY ){
        storeLastErrno(pFile, tErrno);
      }
    }
    return rc;
  } 
  
  /* got it, set the type and return ok */

    pFile->eFileLock = SHARED_LOCK;
    return SQLITE_OK;
  }
  
  /* To fully unlock the database, delete the lock file */
  assert( eFileLock==NO_LOCK );
  rc = osRmdir(zLockFile);

  if( rc<0 ){
    int tErrno = errno;

    if( tErrno==ENOENT ){
      rc = SQLITE_OK;
    }else{
      rc = SQLITE_IOERR_UNLOCK;
      storeLastErrno(pFile, tErrno);
    }
    return rc; 
  }
  pFile->eFileLock = NO_LOCK;
  return SQLITE_OK;
}

/*
** Close a file.  Make sure the lock has been released before closing.
*/
static int dotlockClose(sqlite3_file *id) {


  unixFile *pFile = (unixFile*)id;
  assert( id!=0 );
  dotlockUnlock(id, NO_LOCK);
  sqlite3_free(pFile->lockingContext);
  return closeUnixFile(id);


}
/****************** End of the dot-file lock implementation *******************
******************************************************************************/

/******************************************************************************
************************** Begin flock Locking ********************************
**

    if( !lrc ){
      /* got the lock, unlock it */
      lrc = robust_flock(pFile->h, LOCK_UN);
      if ( lrc ) {
        int tErrno = errno;
        /* unlock failed with an error */
        lrc = SQLITE_IOERR_UNLOCK; 

        storeLastErrno(pFile, tErrno);
        rc = lrc;

      }
    } else {
      int tErrno = errno;
      reserved = 1;
      /* someone else might have it reserved */
      lrc = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_LOCK); 
      if( IS_LOCK_ERROR(lrc) ){

  }
}

/*
** Close a file.
*/
static int flockClose(sqlite3_file *id) {

  assert( id!=0 );
  flockUnlock(id, NO_LOCK);
  return closeUnixFile(id);


}

#endif /* SQLITE_ENABLE_LOCKING_STYLE && !OS_VXWORK */

/******************* End of the flock lock implementation *********************
******************************************************************************/

}

/*
** Close a file & cleanup AFP specific locking context 
*/
static int afpClose(sqlite3_file *id) {
  int rc = SQLITE_OK;

  unixFile *pFile = (unixFile*)id;
  assert( id!=0 );
  afpUnlock(id, NO_LOCK);
  unixEnterMutex();
  if( pFile->pInode && pFile->pInode->nLock ){
    /* If there are outstanding locks, do not actually close the file just
    ** yet because that would clear those locks.  Instead, add the file
    ** descriptor to pInode->aPending.  It will be automatically closed when
    ** the last lock is cleared.
    */
    setPendingFd(pFile);
  }
  releaseInodeInfo(pFile);
  sqlite3_free(pFile->lockingContext);
  rc = closeUnixFile(id);
  unixLeaveMutex();

  return rc;
}

#endif /* defined(__APPLE__) && SQLITE_ENABLE_LOCKING_STYLE */
/*
** The code above is the AFP lock implementation.  The code is specific
** to MacOSX and does not work on other unix platforms.  No alternative

    got = osPread(id->h, pBuf, cnt, offset);
    SimulateIOError( got = -1 );
#elif defined(USE_PREAD64)
    got = osPread64(id->h, pBuf, cnt, offset);
    SimulateIOError( got = -1 );
#else
    newOffset = lseek(id->h, offset, SEEK_SET);
    SimulateIOError( newOffset = -1 );
    if( newOffset<0 ){

      storeLastErrno((unixFile*)id, errno);



      return -1;
    }
    got = osRead(id->h, pBuf, cnt);
#endif
    if( got==cnt ) break;
    if( got<0 ){
      if( errno==EINTR ){ got = 1; continue; }

  int nBuf,                       /* Size of buffer pBuf in bytes */
  int *piErrno                    /* OUT: Error number if error occurs */
){
  int rc = 0;                     /* Value returned by system call */

  assert( nBuf==(nBuf&0x1ffff) );
  assert( fd>2 );
  assert( piErrno!=0 );
  nBuf &= 0x1ffff;
  TIMER_START;

#if defined(USE_PREAD)
  do{ rc = (int)osPwrite(fd, pBuf, nBuf, iOff); }while( rc<0 && errno==EINTR );
#elif defined(USE_PREAD64)
  do{ rc = (int)osPwrite64(fd, pBuf, nBuf, iOff);}while( rc<0 && errno==EINTR);
#else
  do{
    i64 iSeek = lseek(fd, iOff, SEEK_SET);
    SimulateIOError( iSeek = -1 );

    if( iSeek<0 ){

      rc = -1;
      break;
    }
    rc = osWrite(fd, pBuf, nBuf);
  }while( rc<0 && errno==EINTR );
#endif

  TIMER_END;
  OSTRACE(("WRITE   %-3d %5d %7lld %llu\n", fd, rc, iOff, TIMER_ELAPSED));

  if( rc<0 ) *piErrno = errno;
  return rc;
}


/*
** Seek to the offset in id->offset then read cnt bytes into pBuf.
** Return the number of bytes actually read.  Update the offset.

      if( rc!=4 || memcmp(oldCntr, &((char*)pBuf)[24-offset], 4)!=0 ){
        pFile->transCntrChng = 1;  /* The transaction counter has changed */
      }
    }
  }
#endif

#if defined(SQLITE_MMAP_READWRITE) && SQLITE_MAX_MMAP_SIZE>0
  /* Deal with as much of this write request as possible by transfering
  ** data from the memory mapping using memcpy().  */
  if( offset<pFile->mmapSize ){
    if( offset+amt <= pFile->mmapSize ){
      memcpy(&((u8 *)(pFile->pMapRegion))[offset], pBuf, amt);
      return SQLITE_OK;
    }else{

  */
#ifdef SQLITE_TEST
  if( fullSync ) sqlite3_fullsync_count++;
  sqlite3_sync_count++;
#endif

  /* If we compiled with the SQLITE_NO_SYNC flag, then syncing is a
  ** no-op.  But go ahead and call fstat() to validate the file
  ** descriptor as we need a method to provoke a failure during
  ** coverate testing.
  */
#ifdef SQLITE_NO_SYNC
  {
    struct stat buf;
    rc = osFstat(fd, &buf);
  }
#elif HAVE_FULLFSYNC
  if( fullSync ){
    rc = osFcntl(fd, F_FULLFSYNC, 0);
  }else{
    rc = 1;
  }
  /* If the FULLFSYNC failed, fall back to attempting an fsync().

static int openDirectory(const char *zFilename, int *pFd){
  int ii;
  int fd = -1;
  char zDirname[MAX_PATHNAME+1];

  sqlite3_snprintf(MAX_PATHNAME, zDirname, "%s", zFilename);
  for(ii=(int)strlen(zDirname); ii>1 && zDirname[ii]!='/'; ii--);
  if( ii>1 ){
    zDirname[ii] = '\0';
    fd = robust_open(zDirname, O_RDONLY|O_BINARY, 0);
    if( fd>=0 ){
      OSTRACE(("OPENDIR %-3d %s\n", fd, zDirname));
    }
  }
  *pFd = fd;
  if( fd>=0 ) return SQLITE_OK;
  return unixLogError(SQLITE_CANTOPEN_BKPT, "openDirectory", zDirname);
}

/*
** Make sure all writes to a particular file are committed to disk.
**
** If dataOnly==0 then both the file itself and its metadata (file
** size, access time, etc) are synced.  If dataOnly!=0 then only the

  ** are unable to fsync a directory, so ignore errors on the fsync.
  */
  if( pFile->ctrlFlags & UNIXFILE_DIRSYNC ){
    int dirfd;
    OSTRACE(("DIRSYNC %s (have_fullfsync=%d fullsync=%d)\n", pFile->zPath,
            HAVE_FULLFSYNC, isFullsync));
    rc = osOpenDirectory(pFile->zPath, &dirfd);
    if( rc==SQLITE_OK ){
      full_fsync(dirfd, 0, 0);
      robust_close(pFile, dirfd, __LINE__);
    }else{
      assert( rc==SQLITE_CANTOPEN );
      rc = SQLITE_OK;
    }
    pFile->ctrlFlags &= ~UNIXFILE_DIRSYNC;
  }
  return rc;
}

      ** This is a similar technique to that used by glibc on systems
      ** that do not have a real fallocate() call.
      */
      int nBlk = buf.st_blksize;  /* File-system block size */
      int nWrite = 0;             /* Number of bytes written by seekAndWrite */
      i64 iWrite;                 /* Next offset to write to */

      iWrite = (buf.st_size/nBlk)*nBlk + nBlk - 1;
      assert( iWrite>=buf.st_size );

      assert( ((iWrite+1)%nBlk)==0 );
      for(/*no-op*/; iWrite<nSize+nBlk-1; iWrite+=nBlk ){
        if( iWrite>=nSize ) iWrite = nSize - 1;
        nWrite = seekAndWrite(pFile, iWrite, "", 1);
        if( nWrite!=1 ) return SQLITE_IOERR_WRITE;
      }




#endif
    }
  }

#if SQLITE_MAX_MMAP_SIZE>0
  if( pFile->mmapSizeMax>0 && nByte>pFile->mmapSize ){
    int rc;

/*
** Information and control of an open file handle.
*/
static int unixFileControl(sqlite3_file *id, int op, void *pArg){
  unixFile *pFile = (unixFile*)id;
  switch( op ){




    case SQLITE_FCNTL_LOCKSTATE: {
      *(int*)pArg = pFile->eFileLock;
      return SQLITE_OK;
    }
    case SQLITE_FCNTL_LAST_ERRNO: {
      *(int*)pArg = pFile->lastErrno;
      return SQLITE_OK;

  pShmNode = pFile->pInode->pShmNode;
  assert( sqlite3_mutex_held(pShmNode->mutex) || pShmNode->nRef==0 );

  /* Shared locks never span more than one byte */
  assert( n==1 || lockType!=F_RDLCK );

  /* Locks are within range */
  assert( n>=1 && n<=SQLITE_SHM_NLOCK );

  if( pShmNode->h>=0 ){

    /* Initialize the locking parameters */
    memset(&f, 0, sizeof(f));
    f.l_type = lockType;
    f.l_whence = SEEK_SET;
    f.l_start = ofst;
    f.l_len = n;


    rc = osFcntl(pShmNode->h, F_SETLK, &f);
    rc = (rc!=(-1)) ? SQLITE_OK : SQLITE_BUSY;

  }

  /* Update the global lock state and do debug tracing */
#ifdef SQLITE_DEBUG
  { u16 mask;
  OSTRACE(("SHM-LOCK "));
  mask = ofst>31 ? 0xffff : (1<<(ofst+n)) - (1<<ofst);

**
** This is not a VFS shared-memory method; it is a utility function called
** by VFS shared-memory methods.
*/
static void unixShmPurge(unixFile *pFd){
  unixShmNode *p = pFd->pInode->pShmNode;
  assert( unixMutexHeld() );
  if( p && ALWAYS(p->nRef==0) ){
    int nShmPerMap = unixShmRegionPerMap();
    int i;
    assert( p->pInode==pFd->pInode );
    sqlite3_mutex_free(p->mutex);
    for(i=0; i<p->nRegion; i+=nShmPerMap){
      if( p->h>=0 ){
        osMunmap(p->apRegion[i], p->szRegion);

    const char *zBasePath = pDbFd->zPath;
#endif

    /* Call fstat() to figure out the permissions on the database file. If
    ** a new *-shm file is created, an attempt will be made to create it
    ** with the same permissions.
    */
    if( osFstat(pDbFd->h, &sStat) ){
      rc = SQLITE_IOERR_FSTAT;
      goto shm_open_err;
    }

#ifdef SQLITE_SHM_DIRECTORY
    nShmFilename = sizeof(SQLITE_SHM_DIRECTORY) + 31;
#else

        goto shm_open_err;
      }

      /* If this process is running as root, make sure that the SHM file
      ** is owned by the same user that owns the original database.  Otherwise,
      ** the original owner will not be able to connect.
      */
      robustFchown(pShmNode->h, sStat.st_uid, sStat.st_gid);
  
      /* Check to see if another process is holding the dead-man switch.
      ** If not, truncate the file to zero length. 
      */
      rc = SQLITE_OK;
      if( unixShmSystemLock(pDbFd, F_WRLCK, UNIX_SHM_DMS, 1)==SQLITE_OK ){
        if( robust_ftruncate(pShmNode->h, 0) ){

        else{
          static const int pgsz = 4096;
          int iPg;

          /* Write to the last byte of each newly allocated or extended page */
          assert( (nByte % pgsz)==0 );
          for(iPg=(sStat.st_size/pgsz); iPg<(nByte/pgsz); iPg++){
            int x = 0;
            if( seekAndWriteFd(pShmNode->h, iPg*pgsz + pgsz-1, "", 1, &x)!=1 ){
              const char *zFile = pShmNode->zFilename;
              rc = unixLogError(SQLITE_IOERR_SHMSIZE, "write", zFile);
              goto shmpage_out;
            }
          }
        }
      }

  assert( pFd->nFetchOut==0 );
  assert( nNew>pFd->mmapSize );
  assert( nNew<=pFd->mmapSizeMax );
  assert( nNew>0 );
  assert( pFd->mmapSizeActual>=pFd->mmapSize );
  assert( MAP_FAILED!=0 );

#ifdef SQLITE_MMAP_READWRITE
  if( (pFd->ctrlFlags & UNIXFILE_RDONLY)==0 ) flags |= PROT_WRITE;
#endif

  if( pOrig ){
#if HAVE_MREMAP
    i64 nReuse = pFd->mmapSize;
#else
    const int szSyspage = osGetpagesize();
    i64 nReuse = (pFd->mmapSize & ~(szSyspage-1));

** created mapping is either the requested size or the value configured 
** using SQLITE_FCNTL_MMAP_LIMIT, whichever is smaller.
**
** SQLITE_OK is returned if no error occurs (even if the mapping is not
** recreated as a result of outstanding references) or an SQLite error
** code otherwise.
*/
static int unixMapfile(unixFile *pFd, i64 nMap){



  assert( nMap>=0 || pFd->nFetchOut==0 );
  assert( nMap>0 || (pFd->mmapSize==0 && pFd->pMapRegion==0) );
  if( pFd->nFetchOut>0 ) return SQLITE_OK;

  if( nMap<0 ){
    struct stat statbuf;          /* Low-level file information */
    if( osFstat(pFd->h, &statbuf) ){

      return SQLITE_IOERR_FSTAT;
    }
    nMap = statbuf.st_size;
  }
  if( nMap>pFd->mmapSizeMax ){
    nMap = pFd->mmapSizeMax;
  }

  assert( nMap>0 || (pFd->mmapSize==0 && pFd->pMapRegion==0) );
  if( nMap!=pFd->mmapSize ){

    unixRemapfile(pFd, nMap);



  }

  return SQLITE_OK;
}
#endif /* SQLITE_MAX_MMAP_SIZE>0 */

/*

** Return the name of a directory in which to put temporary files.
** If no suitable temporary file directory can be found, return NULL.
*/
static const char *unixTempFileDir(void){
  static const char *azDirs[] = {
     0,
     0,

     "/var/tmp",
     "/usr/tmp",
     "/tmp",

     "."
  };
  unsigned int i;
  struct stat buf;
  const char *zDir = sqlite3_temp_directory;

  if( !azDirs[0] ) azDirs[0] = getenv("SQLITE_TMPDIR");
  if( !azDirs[1] ) azDirs[1] = getenv("TMPDIR");

  for(i=0; i<sizeof(azDirs)/sizeof(azDirs[0]); zDir=azDirs[i++]){
    if( zDir==0 ) continue;
    if( osStat(zDir, &buf) ) continue;
    if( !S_ISDIR(buf.st_mode) ) continue;
    if( osAccess(zDir, 07) ) continue;
    break;
  }
  return zDir;
}

/*
** Create a temporary file name in zBuf.  zBuf must be allocated
** by the calling process and must be big enough to hold at least
** pVfs->mxPathname bytes.
*/
static int unixGetTempname(int nBuf, char *zBuf){





  const char *zDir;
  int iLimit = 0;

  /* It's odd to simulate an io-error here, but really this is just
  ** using the io-error infrastructure to test that SQLite handles this
  ** function failing. 
  */
  SimulateIOError( return SQLITE_IOERR );

  zDir = unixTempFileDir();









  do{


    u64 r;
    sqlite3_randomness(sizeof(r), &r);



    assert( nBuf>2 );
    zBuf[nBuf-2] = 0;
    sqlite3_snprintf(nBuf, zBuf, "%s/"SQLITE_TEMP_FILE_PREFIX"%llx%c",
                     zDir, r, 0);
    if( zBuf[nBuf-2]!=0 || (iLimit++)>10 ) return SQLITE_ERROR;
  }while( osAccess(zBuf,0)==0 );
  return SQLITE_OK;
}

#if SQLITE_ENABLE_LOCKING_STYLE && defined(__APPLE__)
/*
** Routine to transform a unixFile into a proxy-locking unixFile.

    **   "<path to db>-journalNN"
    **   "<path to db>-walNN"
    **
    ** where NN is a decimal number. The NN naming schemes are 
    ** used by the test_multiplex.c module.
    */
    nDb = sqlite3Strlen30(zPath) - 1; 
    while( zPath[nDb]!='-' ){
#ifndef SQLITE_ENABLE_8_3_NAMES
      /* In the normal case (8+3 filenames disabled) the journal filename
      ** is guaranteed to contain a '-' character. */
      assert( nDb>0 );
      assert( sqlite3Isalnum(zPath[nDb]) );

#else
      /* If 8+3 names are possible, then the journal file might not contain
      ** a '-' character.  So check for that case and return early. */
      if( nDb==0 || zPath[nDb]=='.' ) return SQLITE_OK;


#endif
      nDb--;
    }

    memcpy(zDb, zPath, nDb);
    zDb[nDb] = '\0';

    if( 0==osStat(zDb, &sStat) ){
      *pMode = sStat.st_mode & 0777;
      *pUid = sStat.st_uid;
      *pGid = sStat.st_gid;

    ** URIs with parameters.  Hence, they can always be passed into
    ** sqlite3_uri_parameter(). */
    assert( (flags & SQLITE_OPEN_URI) || zName[strlen(zName)+1]==0 );

  }else if( !zName ){
    /* If zName is NULL, the upper layer is requesting a temp file. */
    assert(isDelete && !syncDir);
    rc = unixGetTempname(pVfs->mxPathname, zTmpname);
    if( rc!=SQLITE_OK ){
      return rc;
    }
    zName = zTmpname;

    /* Generated temporary filenames are always double-zero terminated
    ** for use by sqlite3_uri_parameter(). */

    if( rc!=SQLITE_OK ){
      assert( !p->pUnused );
      assert( eType==SQLITE_OPEN_WAL || eType==SQLITE_OPEN_MAIN_JOURNAL );
      return rc;
    }
    fd = robust_open(zName, openFlags, openMode);
    OSTRACE(("OPENX   %-3d %s 0%o\n", fd, zName, openFlags));
    assert( !isExclusive || (openFlags & O_CREAT)!=0 );
    if( fd<0 && errno!=EISDIR && isReadWrite ){
      /* Failed to open the file for read/write access. Try read-only. */
      flags &= ~(SQLITE_OPEN_READWRITE|SQLITE_OPEN_CREATE);
      openFlags &= ~(O_RDWR|O_CREAT);
      flags |= SQLITE_OPEN_READONLY;
      openFlags |= O_RDONLY;
      isReadonly = 1;
      fd = robust_open(zName, openFlags, openMode);
    }
    if( fd<0 ){
      rc = unixLogError(SQLITE_CANTOPEN_BKPT, "open", zName);
      goto open_finished;
    }

    /* If this process is running as root and if creating a new rollback
    ** journal or WAL file, set the ownership of the journal or WAL to be
    ** the same as the original database.
    */
    if( flags & (SQLITE_OPEN_WAL|SQLITE_OPEN_MAIN_JOURNAL) ){
      robustFchown(fd, uid, gid);
    }
  }
  assert( fd>=0 );
  if( pOutFlags ){
    *pOutFlags = flags;
  }

#else
      if( fsync(fd) )
#endif
      {
        rc = unixLogError(SQLITE_IOERR_DIR_FSYNC, "fsync", zPath);
      }
      robust_close(0, fd, __LINE__);
    }else{
      assert( rc==SQLITE_CANTOPEN );
      rc = SQLITE_OK;
    }
  }
#endif
  return rc;
}

*/
static int unixAccess(
  sqlite3_vfs *NotUsed,   /* The VFS containing this xAccess method */
  const char *zPath,      /* Path of the file to examine */
  int flags,              /* What do we want to learn about the zPath file? */
  int *pResOut            /* Write result boolean here */
){

  UNUSED_PARAMETER(NotUsed);
  SimulateIOError( return SQLITE_IOERR_ACCESS; );
  assert( pResOut!=0 );











  /* The spec says there are three possible values for flags.  But only
  ** two of them are actually used */
  assert( flags==SQLITE_ACCESS_EXISTS || flags==SQLITE_ACCESS_READWRITE );


  if( flags==SQLITE_ACCESS_EXISTS ){
    struct stat buf;
    *pResOut = (0==osStat(zPath, &buf) && buf.st_size>0);
  }else{
    *pResOut = osAccess(zPath, W_OK|R_OK)==0;

  }
  return SQLITE_OK;
}


/*
** Turn a relative pathname into a full pathname. The relative path
** is stored as a nul-terminated string in the buffer pointed to by
** zPath. 
**
** zOut points to a buffer of at least sqlite3_vfs.mxPathname bytes 
** (in this case, MAX_PATHNAME bytes). The full-path is written to
** this buffer before returning.
*/
static int unixFullPathname(
  sqlite3_vfs *pVfs,            /* Pointer to vfs object */
  const char *zPath,            /* Possibly relative input path */
  int nOut,                     /* Size of output buffer in bytes */
  char *zOut                    /* Output buffer */
){
  int nByte;

  /* It's odd to simulate an io-error here, but really this is just
  ** using the io-error infrastructure to test that SQLite handles this
  ** function failing. This function could fail if, for example, the
  ** current working directory has been unlinked.
  */
  SimulateIOError( return SQLITE_ERROR );

  assert( pVfs->mxPathname==MAX_PATHNAME );
  UNUSED_PARAMETER(pVfs);

  /* Attempt to resolve the path as if it were a symbolic link. If it is
  ** a symbolic link, the resolved path is stored in buffer zOut[]. Or, if
  ** the identified file is not a symbolic link or does not exist, then
  ** zPath is copied directly into zOut. Either way, nByte is left set to
  ** the size of the string copied into zOut[] in bytes.  */
  nByte = osReadlink(zPath, zOut, nOut-1);
  if( nByte<0 ){
    if( errno!=EINVAL && errno!=ENOENT ){
      return unixLogError(SQLITE_CANTOPEN_BKPT, "readlink", zPath);
    }
    sqlite3_snprintf(nOut, zOut, "%s", zPath);
    nByte = sqlite3Strlen30(zOut);
  }else{
    zOut[nByte] = '\0';
  }

  /* If buffer zOut[] now contains an absolute path there is nothing more
  ** to do. If it contains a relative path, do the following:
  **
  **   * move the relative path string so that it is at the end of th
  **     zOut[] buffer.
  **   * Call getcwd() to read the path of the current working directory 
  **     into the start of the zOut[] buffer.
  **   * Append a '/' character to the cwd string and move the 
  **     relative path back within the buffer so that it immediately 
  **     follows the '/'.
  **
  ** This code is written so that if the combination of the CWD and relative
  ** path are larger than the allocated size of zOut[] the CWD is silently
  ** truncated to make it fit. This is Ok, as SQLite refuses to open any
  ** file for which this function returns a full path larger than (nOut-8)
  ** bytes in size.  */
  testcase( nByte==nOut-5 );
  testcase( nByte==nOut-4 );
  if( zOut[0]!='/' && nByte<nOut-4 ){
    int nCwd;
    int nRem = nOut-nByte-1;
    memmove(&zOut[nRem], zOut, nByte+1);
    zOut[nRem-1] = '\0';
    if( osGetcwd(zOut, nRem-1)==0 ){
      return unixLogError(SQLITE_CANTOPEN_BKPT, "getcwd", zPath);
    }
    nCwd = sqlite3Strlen30(zOut);
    assert( nCwd<=nRem-1 );
    zOut[nCwd] = '/';
    memmove(&zOut[nCwd+1], &zOut[nRem], nByte+1);
  }

  return SQLITE_OK;
}


#ifndef SQLITE_OMIT_LOAD_EXTENSION
/*
** Interfaces for opening a shared library, finding entry points

  *piNow = ((sqlite3_int64)t)*1000 + unixEpoch;
#elif OS_VXWORKS
  struct timespec sNow;
  clock_gettime(CLOCK_REALTIME, &sNow);
  *piNow = unixEpoch + 1000*(sqlite3_int64)sNow.tv_sec + sNow.tv_nsec/1000000;
#else
  struct timeval sNow;
  (void)gettimeofday(&sNow, 0);  /* Cannot fail given valid arguments */
  *piNow = unixEpoch + 1000*(sqlite3_int64)sNow.tv_sec + sNow.tv_usec/1000;



#endif

#ifdef SQLITE_TEST
  if( sqlite3_current_time ){
    *piNow = 1000*(sqlite3_int64)sqlite3_current_time + unixEpoch;
  }
#endif
  UNUSED_PARAMETER(NotUsed);
  return rc;
}

#if 0 /* Not used */
/*
** Find the current time (in Universal Coordinated Time).  Write the
** current time and date as a Julian Day number into *prNow and
** return 0.  Return 1 if the time and date cannot be found.
*/
static int unixCurrentTime(sqlite3_vfs *NotUsed, double *prNow){
  sqlite3_int64 i = 0;
  int rc;
  UNUSED_PARAMETER(NotUsed);
  rc = unixCurrentTimeInt64(0, &i);
  *prNow = i/86400000.0;
  return rc;
}
#else
# define unixCurrentTime 0
#endif

#if 0  /* Not used */
/*
** We added the xGetLastError() method with the intention of providing
** better low-level error messages when operating-system problems come up
** during SQLite operation.  But so far, none of that has been implemented
** in the core.  So this routine is never called.  For now, it is merely
** a place-holder.
*/
static int unixGetLastError(sqlite3_vfs *NotUsed, int NotUsed2, char *NotUsed3){
  UNUSED_PARAMETER(NotUsed);
  UNUSED_PARAMETER(NotUsed2);
  UNUSED_PARAMETER(NotUsed3);
  return 0;
}
#else
# define unixGetLastError 0
#endif


/*
************************ End of sqlite3_vfs methods ***************************
******************************************************************************/

/******************************************************************************

          }
        }
      }
      start=i+1;
    }
    buf[i] = lockPath[i];
  }
  OSTRACE(("CREATELOCKPATH  proxy lock path=%s pid=%d\n",lockPath,osGetpid(0)));
  return 0;
}

/*
** Create a new VFS file descriptor (stored in memory obtained from
** sqlite3_malloc) and open the file named "path" in the file descriptor.
**

  return rc;
}

/*
** Close a file that uses proxy locks.
*/
static int proxyClose(sqlite3_file *id) {
  if( ALWAYS(id) ){
    unixFile *pFile = (unixFile*)id;
    proxyLockingContext *pCtx = (proxyLockingContext *)pFile->lockingContext;
    unixFile *lockProxy = pCtx->lockProxy;
    unixFile *conchFile = pCtx->conchFile;
    int rc = SQLITE_OK;
    
    if( lockProxy ){

    UNIXVFS("unix-proxy",    proxyIoFinder ),
#endif
  };
  unsigned int i;          /* Loop counter */

  /* Double-check that the aSyscall[] array has been constructed
  ** correctly.  See ticket [bb3a86e890c8e96ab] */
  assert( ArraySize(aSyscall)==27 );

  /* Register all VFSes defined in the aVfs[] array */
  for(i=0; i<(sizeof(aVfs)/sizeof(sqlite3_vfs)); i++){
    sqlite3_vfs_register(&aVfs[i], i==0);
  }
  return SQLITE_OK; 
}

  SimulateIOError(return SQLITE_IOERR_WRITE);
  SimulateDiskfullError(return SQLITE_FULL);

  OSTRACE(("WRITE pid=%lu, pFile=%p, file=%p, buffer=%p, amount=%d, "
           "offset=%lld, lock=%d\n", osGetCurrentProcessId(), pFile,
           pFile->h, pBuf, amt, offset, pFile->locktype));

#if defined(SQLITE_MMAP_READWRITE) && SQLITE_MAX_MMAP_SIZE>0
  /* Deal with as much of this write request as possible by transfering
  ** data from the memory mapping using memcpy().  */
  if( offset<pFile->mmapSize ){
    if( offset+amt <= pFile->mmapSize ){
      memcpy(&((u8 *)(pFile->pMapRegion))[offset], pBuf, amt);
      OSTRACE(("WRITE-MMAP pid=%lu, pFile=%p, file=%p, rc=SQLITE_OK\n",
               osGetCurrentProcessId(), pFile, pFile->h));

  OSTRACE(("TEST-WR-LOCK file=%p, pResOut=%p\n", pFile->h, pResOut));

  assert( id!=0 );
  if( pFile->locktype>=RESERVED_LOCK ){
    res = 1;
    OSTRACE(("TEST-WR-LOCK file=%p, result=%d (local)\n", pFile->h, res));
  }else{
    res = winLockFile(&pFile->h, SQLITE_LOCKFILEEX_FLAGS,RESERVED_BYTE,0,1,0);
    if( res ){
      winUnlockFile(&pFile->h, RESERVED_BYTE, 0, 1, 0);
    }
    res = !res;
    OSTRACE(("TEST-WR-LOCK file=%p, result=%d (remote)\n", pFile->h, res));
  }
  *pResOut = res;

  }
  if( nMap!=pFd->mmapSize ){
    void *pNew = 0;
    DWORD protect = PAGE_READONLY;
    DWORD flags = FILE_MAP_READ;

    winUnmapfile(pFd);
#ifdef SQLITE_MMAP_READWRITE
    if( (pFd->ctrlFlags & WINFILE_RDONLY)==0 ){
      protect = PAGE_READWRITE;
      flags |= FILE_MAP_WRITE;
    }
#endif
#if SQLITE_OS_WINRT
    pFd->hMap = osCreateFileMappingFromApp(pFd->h, NULL, protect, nMap, NULL);
#elif defined(SQLITE_WIN32_HAS_WIDE)
    pFd->hMap = osCreateFileMappingW(pFd->h, NULL, protect,
                                (DWORD)((nMap>>32) & 0xffffffff),
                                (DWORD)(nMap & 0xffffffff), NULL);
#elif defined(SQLITE_WIN32_HAS_ANSI)

/* #include "sqliteInt.h" */

/* Size of the Bitvec structure in bytes. */
#define BITVEC_SZ        512

/* Round the union size down to the nearest pointer boundary, since that's how 
** it will be aligned within the Bitvec struct. */
#define BITVEC_USIZE \
    (((BITVEC_SZ-(3*sizeof(u32)))/sizeof(Bitvec*))*sizeof(Bitvec*))

/* Type of the array "element" for the bitmap representation. 
** Should be a power of 2, and ideally, evenly divide into BITVEC_USIZE. 
** Setting this to the "natural word" size of your CPU may improve
** performance. */
#define BITVEC_TELEM     u8
/* Size, in bits, of the bitmap element. */

** A complete page cache is an instance of this structure.
*/
struct PCache {
  PgHdr *pDirty, *pDirtyTail;         /* List of dirty pages in LRU order */
  PgHdr *pSynced;                     /* Last synced page in dirty page list */
  int nRefSum;                        /* Sum of ref counts over all pages */
  int szCache;                        /* Configured cache size */
  int szSpill;                        /* Size before spilling occurs */
  int szPage;                         /* Size of every page in this cache */
  int szExtra;                        /* Size of extra space for each page */
  u8 bPurgeable;                      /* True if pages are on backing store */
  u8 eCreate;                         /* eCreate value for for xFetch() */
  int (*xStress)(void*,PgHdr*);       /* Call to try make a page clean */
  void *pStress;                      /* Argument to xStress */
  sqlite3_pcache *pCache;             /* Pluggable cache module */

static void pcacheUnpin(PgHdr *p){
  if( p->pCache->bPurgeable ){
    sqlite3GlobalConfig.pcache2.xUnpin(p->pCache->pCache, p->pPage, 0);
  }
}

/*
** Compute the number of pages of cache requested.   p->szCache is the
** cache size requested by the "PRAGMA cache_size" statement.


*/
static int numberOfCachePages(PCache *p){
  if( p->szCache>=0 ){
    /* IMPLEMENTATION-OF: R-42059-47211 If the argument N is positive then the
    ** suggested cache size is set to N. */
    return p->szCache;
  }else{

  p->szPage = 1;
  p->szExtra = szExtra;
  p->bPurgeable = bPurgeable;
  p->eCreate = 2;
  p->xStress = xStress;
  p->pStress = pStress;
  p->szCache = 100;
  p->szSpill = 1;
  return sqlite3PcacheSetPageSize(p, szPage);
}

/*
** Change the page size for PCache object. The caller must ensure that there
** are no outstanding page references when this function is called.
*/

  PCache *pCache,                 /* Obtain the page from this cache */
  Pgno pgno,                      /* Page number to obtain */
  sqlite3_pcache_page **ppPage    /* Write result here */
){
  PgHdr *pPg;
  if( pCache->eCreate==2 ) return 0;

  if( sqlite3PcachePagecount(pCache)>pCache->szSpill ){
    /* Find a dirty page to write-out and recycle. First try to find a 
    ** page that does not require a journal-sync (one with PGHDR_NEED_SYNC
    ** cleared), but if that is not possible settle for any other 
    ** unreferenced dirty page.
    */
    for(pPg=pCache->pSynced; 
        pPg && (pPg->nRef || (pPg->flags&PGHDR_NEED_SYNC)); 
        pPg=pPg->pDirtyPrev
    );
    pCache->pSynced = pPg;
    if( !pPg ){
      for(pPg=pCache->pDirtyTail; pPg && pPg->nRef; pPg=pPg->pDirtyPrev);
    }
    if( pPg ){
      int rc;
#ifdef SQLITE_LOG_CACHE_SPILL
      sqlite3_log(SQLITE_FULL, 
                  "spill page %d making room for %d - cache used: %d/%d",
                  pPg->pgno, pgno,
                  sqlite3GlobalConfig.pcache.xPagecount(pCache->pCache),
                numberOfCachePages(pCache));
#endif
      rc = pCache->xStress(pCache->pStress, pPg);
      if( rc!=SQLITE_OK && rc!=SQLITE_BUSY ){
        return rc;
      }
    }
  }
  *ppPage = sqlite3GlobalConfig.pcache2.xFetch(pCache->pCache, pgno, 2);
  return *ppPage==0 ? SQLITE_NOMEM : SQLITE_OK;
}

/*

*/
SQLITE_PRIVATE void sqlite3PcacheSetCachesize(PCache *pCache, int mxPage){
  assert( pCache->pCache!=0 );
  pCache->szCache = mxPage;
  sqlite3GlobalConfig.pcache2.xCachesize(pCache->pCache,
                                         numberOfCachePages(pCache));
}

/*
** Set the suggested cache-spill value.  Make no changes if if the
** argument is zero.  Return the effective cache-spill size, which will
** be the larger of the szSpill and szCache.
*/
SQLITE_PRIVATE int sqlite3PcacheSetSpillsize(PCache *p, int mxPage){
  int res;
  assert( p->pCache!=0 );
  if( mxPage ){
    if( mxPage<0 ){
      mxPage = (int)((-1024*(i64)mxPage)/(p->szPage+p->szExtra));
    }
    p->szSpill = mxPage;
  }
  res = numberOfCachePages(p);
  if( res<p->szSpill ) res = p->szSpill; 
  return res;
}

/*
** Free up as much memory as possible from the page cache.
*/
SQLITE_PRIVATE void sqlite3PcacheShrink(PCache *pCache){
  assert( pCache->pCache!=0 );
  sqlite3GlobalConfig.pcache2.xShrink(pCache->pCache);

**         SQLITE_CONFIG_PAGECACHE.
**    (3)  PCache-local bulk allocation.
**
** The third case is a chunk of heap memory (defaulting to 100 pages worth)
** that is allocated when the page cache is created.  The size of the local
** bulk allocation can be adjusted using 
**
**     sqlite3_config(SQLITE_CONFIG_PAGECACHE, (void*)0, 0, N).
**
** If N is positive, then N pages worth of memory are allocated using a single
** sqlite3Malloc() call and that memory is used for the first N pages allocated.
** Or if N is negative, then -1024*N bytes of memory are allocated and used
** for as many pages as can be accomodated.
**
** Only one of (2) or (3) can be used.  Once the memory available to (2) or

    sqlite3_mutex_enter(pcache1.mutex);
    p = (PgHdr1 *)pcache1.pFree;
    if( p ){
      pcache1.pFree = pcache1.pFree->pNext;
      pcache1.nFreeSlot--;
      pcache1.bUnderPressure = pcache1.nFreeSlot<pcache1.nReserve;
      assert( pcache1.nFreeSlot>=0 );
      sqlite3StatusHighwater(SQLITE_STATUS_PAGECACHE_SIZE, nByte);
      sqlite3StatusUp(SQLITE_STATUS_PAGECACHE_USED, 1);
    }
    sqlite3_mutex_leave(pcache1.mutex);
  }
  if( p==0 ){
    /* Memory is not available in the SQLITE_CONFIG_PAGECACHE pool.  Get
    ** it from sqlite3Malloc instead.
    */
    p = sqlite3Malloc(nByte);
#ifndef SQLITE_DISABLE_PAGECACHE_OVERFLOW_STATS
    if( p ){
      int sz = sqlite3MallocSize(p);
      sqlite3_mutex_enter(pcache1.mutex);
      sqlite3StatusHighwater(SQLITE_STATUS_PAGECACHE_SIZE, nByte);
      sqlite3StatusUp(SQLITE_STATUS_PAGECACHE_OVERFLOW, sz);
      sqlite3_mutex_leave(pcache1.mutex);
    }
#endif
    sqlite3MemdebugSetType(p, MEMTYPE_PCACHE);
  }
  return p;

    ** the data just read from the sub-journal. Mark the page as dirty 
    ** and if the pager requires a journal-sync, then mark the page as 
    ** requiring a journal-sync before it is written.
    */
    assert( isSavepnt );
    assert( (pPager->doNotSpill & SPILLFLAG_ROLLBACK)==0 );
    pPager->doNotSpill |= SPILLFLAG_ROLLBACK;
    rc = sqlite3PagerGet(pPager, pgno, &pPg, 1);
    assert( (pPager->doNotSpill & SPILLFLAG_ROLLBACK)!=0 );
    pPager->doNotSpill &= ~SPILLFLAG_ROLLBACK;
    if( rc!=SQLITE_OK ) return rc;
    pPg->flags &= ~PGHDR_NEED_READ;
    sqlite3PcacheMakeDirty(pPg);
  }
  if( pPg ){

    pPager->journalOff = szJ;
  }

  return rc;
}

/*
** Change the maximum number of in-memory pages that are allowed
** before attempting to recycle clean and unused pages.
*/
SQLITE_PRIVATE void sqlite3PagerSetCachesize(Pager *pPager, int mxPage){
  sqlite3PcacheSetCachesize(pPager->pPCache, mxPage);
}

/*
** Change the maximum number of in-memory pages that are allowed
** before attempting to spill pages to journal.
*/
SQLITE_PRIVATE int sqlite3PagerSetSpillsize(Pager *pPager, int mxPage){
  return sqlite3PcacheSetSpillsize(pPager->pPCache, mxPage);
}

/*
** Invoke SQLITE_FCNTL_MMAP_SIZE based on the current value of szMmap.
*/
static void pagerFixMaplimit(Pager *pPager){
#if SQLITE_MAX_MMAP_SIZE>0
  sqlite3_file *fd = pPager->fd;

    PAGERTRACE(("STRESS %d page %d\n", PAGERID(pPager), pPg->pgno));
    sqlite3PcacheMakeClean(pPg);
  }

  return pager_error(pPager, rc); 
}

/*
** Flush all unreferenced dirty pages to disk.
*/
SQLITE_PRIVATE int sqlite3PagerFlush(Pager *pPager){
  int rc = pPager->errCode;
  if( !MEMDB ){
    PgHdr *pList = sqlite3PcacheDirtyList(pPager->pPCache);
    assert( assert_pager_state(pPager) );
    while( rc==SQLITE_OK && pList ){
      PgHdr *pNext = pList->pDirty;
      if( pList->nRef==0 ){
        rc = pagerStress((void*)pPager, pList);
      }
      pList = pNext;
    }
  }

  return rc;
}

/*
** Allocate and initialize a new Pager object and put a pointer to it
** in *ppPager. The pager should eventually be freed by passing it
** to sqlite3PagerClose().
**
** The zFilename argument is the path to the database file to open.

  }

  return rc;
}

/*
** This function is called to obtain a shared lock on the database file.
** It is illegal to call sqlite3PagerGet() until after this function
** has been successfully called. If a shared-lock is already held when
** this function is called, it is a no-op.
**
** The following operations are also performed by this function.
**
**   1) If the pager is currently in PAGER_OPEN state (no lock held
**      on the database file), then an attempt is made to obtain a

** 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.
*/
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 */
){
  int rc = SQLITE_OK;
  PgHdr *pPg = 0;

  assert((pg1+nPage)>pPg->pgno);

  for(ii=0; ii<nPage && rc==SQLITE_OK; ii++){
    Pgno pg = pg1+ii;
    PgHdr *pPage;
    if( pg==pPg->pgno || !sqlite3BitvecTest(pPager->pInJournal, pg) ){
      if( pg!=PAGER_MJ_PGNO(pPager) ){
        rc = sqlite3PagerGet(pPager, pg, &pPage, 0);
        if( rc==SQLITE_OK ){
          rc = pager_write(pPage);
          if( pPage->flags&PGHDR_NEED_SYNC ){
            needSync = 1;
          }
          sqlite3PagerUnrefNotNull(pPage);
        }

** If an error occurs, SQLITE_NOMEM or an IO error code is returned
** 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( pPager->errCode ){
    return pPager->errCode;
  }else if( (pPg->flags & PGHDR_WRITEABLE)!=0 && pPager->dbSize>=pPg->pgno ){
    if( pPager->nSavepoint ) return subjournalPageIfRequired(pPg);
    return SQLITE_OK;
  }else if( pPager->sectorSize > (u32)pPager->pageSize ){
    return pagerWriteLargeSector(pPg);
  }else{
    return pager_write(pPg);
  }

  if( !pPager->changeCountDone && ALWAYS(pPager->dbSize>0) ){
    PgHdr *pPgHdr;                /* Reference to page 1 */

    assert( !pPager->tempFile && isOpen(pPager->fd) );

    /* Open page 1 of the file for writing. */
    rc = sqlite3PagerGet(pPager, 1, &pPgHdr, 0);
    assert( pPgHdr==0 || rc==SQLITE_OK );

    /* If page one was fetched successfully, and this function is not
    ** operating in direct-mode, make page 1 writable.  When not in 
    ** direct mode, page 1 is always held in cache and hence the PagerGet()
    ** above is always successful - hence the ALWAYS on rc==SQLITE_OK.
    */

**
** If the EXCLUSIVE lock is already held or the attempt to obtain it is
** successful, or the connection is in WAL mode, SQLITE_OK is returned.
** Otherwise, either SQLITE_BUSY or an SQLITE_IOERR_XXX error code is 
** returned.
*/
SQLITE_PRIVATE int sqlite3PagerExclusiveLock(Pager *pPager){
  int rc = pPager->errCode;
  assert( assert_pager_state(pPager) );
  if( rc==SQLITE_OK ){
    assert( pPager->eState==PAGER_WRITER_CACHEMOD 
         || pPager->eState==PAGER_WRITER_DBMOD 
         || pPager->eState==PAGER_WRITER_LOCKED 
    );
    assert( assert_pager_state(pPager) );
    if( 0==pagerUseWal(pPager) ){
      rc = pager_wait_on_lock(pPager, EXCLUSIVE_LOCK);
    }
  }
  return rc;
}

/*
** Sync the database file for the pager pPager. zMaster points to the name
** of a master journal file that should be written into the individual

  }else{
    if( pagerUseWal(pPager) ){
      PgHdr *pList = sqlite3PcacheDirtyList(pPager->pPCache);
      PgHdr *pPageOne = 0;
      if( pList==0 ){
        /* Must have at least one page for the WAL commit flag.
        ** Ticket [2d1a5c67dfc2363e44f29d9bbd57f] 2011-05-18 */
        rc = sqlite3PagerGet(pPager, 1, &pPageOne, 0);
        pList = pPageOne;
        pList->pDirty = 0;
      }
      assert( rc==SQLITE_OK );
      if( ALWAYS(pList) ){
        rc = pagerWalFrames(pPager, pList, pPager->dbSize, 1);
      }

SQLITE_PRIVATE const char *sqlite3PagerFilename(Pager *pPager, int nullIfMemDb){
  return (nullIfMemDb && pPager->memDb) ? "" : pPager->zFilename;
}

/*
** Return the VFS structure for the pager.
*/
SQLITE_PRIVATE sqlite3_vfs *sqlite3PagerVfs(Pager *pPager){
  return pPager->pVfs;
}

/*
** Return the file handle for the database file associated
** with the pager.  This might return NULL if the file has
** not yet been opened.

    ** to a malloc() or IO failure), clear the bit in the pInJournal[]
    ** array. Otherwise, if the page is loaded and written again in
    ** this transaction, it may be written to the database file before
    ** it is synced into the journal file. This way, it may end up in
    ** the journal file twice, but that is not a problem.
    */
    PgHdr *pPgHdr;
    rc = sqlite3PagerGet(pPager, needSyncPgno, &pPgHdr, 0);
    if( rc!=SQLITE_OK ){
      if( needSyncPgno<=pPager->dbOrigSize ){
        assert( pPager->pTmpSpace!=0 );
        sqlite3BitvecClear(pPager->pInJournal, needSyncPgno, pPager->pTmpSpace);
      }
      return rc;
    }

}
static void walUnlockShared(Wal *pWal, int lockIdx){
  if( pWal->exclusiveMode ) return;
  (void)sqlite3OsShmLock(pWal->pDbFd, lockIdx, 1,
                         SQLITE_SHM_UNLOCK | SQLITE_SHM_SHARED);
  WALTRACE(("WAL%p: release SHARED-%s\n", pWal, walLockName(lockIdx)));
}
static int walLockExclusive(Wal *pWal, int lockIdx, int n){
  int rc;
  if( pWal->exclusiveMode ) return SQLITE_OK;

  rc = sqlite3OsShmLock(pWal->pDbFd, lockIdx, n,
                        SQLITE_SHM_LOCK | SQLITE_SHM_EXCLUSIVE);
  WALTRACE(("WAL%p: acquire EXCLUSIVE-%s cnt=%d %s\n", pWal,
            walLockName(lockIdx), n, rc ? "failed" : "ok"));
  VVA_ONLY( pWal->lockError = (u8)(rc!=SQLITE_OK && rc!=SQLITE_BUSY); )
  return rc;
}

  */
  assert( pWal->ckptLock==1 || pWal->ckptLock==0 );
  assert( WAL_ALL_BUT_WRITE==WAL_WRITE_LOCK+1 );
  assert( WAL_CKPT_LOCK==WAL_ALL_BUT_WRITE );
  assert( pWal->writeLock );
  iLock = WAL_ALL_BUT_WRITE + pWal->ckptLock;
  nLock = SQLITE_SHM_NLOCK - iLock;
  rc = walLockExclusive(pWal, iLock, nLock);
  if( rc ){
    return rc;
  }
  WALTRACE(("WAL%p: recovery begin...\n", pWal));

  memset(&pWal->hdr, 0, sizeof(WalIndexHdr));

  int (*xBusy)(void*),            /* Function to call when busy */
  void *pBusyArg,                 /* Context argument for xBusyHandler */
  int lockIdx,                    /* Offset of first byte to lock */
  int n                           /* Number of bytes to lock */
){
  int rc;
  do {
    rc = walLockExclusive(pWal, lockIdx, n);
  }while( xBusy && rc==SQLITE_BUSY && xBusy(pBusyArg) );
  return rc;
}

/*
** The cache of the wal-index header must be valid to call this function.
** Return the page-size in bytes used by the database.

  assert( badHdr==0 || pWal->writeLock==0 );
  if( badHdr ){
    if( pWal->readOnly & WAL_SHM_RDONLY ){
      if( SQLITE_OK==(rc = walLockShared(pWal, WAL_WRITE_LOCK)) ){
        walUnlockShared(pWal, WAL_WRITE_LOCK);
        rc = SQLITE_READONLY_RECOVERY;
      }
    }else if( SQLITE_OK==(rc = walLockExclusive(pWal, WAL_WRITE_LOCK, 1)) ){
      pWal->writeLock = 1;
      if( SQLITE_OK==(rc = walIndexPage(pWal, 0, &page0)) ){
        badHdr = walIndexTryHdr(pWal, pChanged);
        if( badHdr ){
          /* If the wal-index header is still malformed even while holding
          ** a WRITE lock, it can only mean that the header is corrupted and
          ** needs to be reconstructed.  So run recovery to do exactly that.

  }
  /* There was once an "if" here. The extra "{" is to preserve indentation. */
  {
    if( (pWal->readOnly & WAL_SHM_RDONLY)==0
     && (mxReadMark<pWal->hdr.mxFrame || mxI==0)
    ){
      for(i=1; i<WAL_NREADER; i++){
        rc = walLockExclusive(pWal, WAL_READ_LOCK(i), 1);
        if( rc==SQLITE_OK ){
          mxReadMark = pInfo->aReadMark[i] = pWal->hdr.mxFrame;
          mxI = i;
          walUnlockExclusive(pWal, WAL_READ_LOCK(i), 1);
          break;
        }else if( rc!=SQLITE_BUSY ){
          return rc;

  if( pWal->readOnly ){
    return SQLITE_READONLY;
  }

  /* Only one writer allowed at a time.  Get the write lock.  Return
  ** SQLITE_BUSY if unable.
  */
  rc = walLockExclusive(pWal, WAL_WRITE_LOCK, 1);
  if( rc ){
    return rc;
  }
  pWal->writeLock = 1;

  /* If another connection has written to the database file since the
  ** time the read transaction on this connection was started, then

  if( pWal->readLock==0 ){
    volatile WalCkptInfo *pInfo = walCkptInfo(pWal);
    assert( pInfo->nBackfill==pWal->hdr.mxFrame );
    if( pInfo->nBackfill>0 ){
      u32 salt1;
      sqlite3_randomness(4, &salt1);
      rc = walLockExclusive(pWal, WAL_READ_LOCK(1), WAL_NREADER-1);
      if( rc==SQLITE_OK ){
        /* If all readers are using WAL_READ_LOCK(0) (in other words if no
        ** readers are currently using the WAL), then the transactions
        ** frames will overwrite the start of the existing log. Update the
        ** wal-index header to reflect this.
        **
        ** In theory it would be Ok to update the cache of the header only

  assert( eMode!=SQLITE_CHECKPOINT_PASSIVE || xBusy==0 );

  if( pWal->readOnly ) return SQLITE_READONLY;
  WALTRACE(("WAL%p: checkpoint begins\n", pWal));

  /* IMPLEMENTATION-OF: R-62028-47212 All calls obtain an exclusive 
  ** "checkpoint" lock on the database file. */
  rc = walLockExclusive(pWal, WAL_CKPT_LOCK, 1);
  if( rc ){
    /* EVIDENCE-OF: R-10421-19736 If any other process is running a
    ** checkpoint operation at the same time, the lock cannot be obtained and
    ** SQLITE_BUSY is returned.
    ** EVIDENCE-OF: R-53820-33897 Even if there is a busy-handler configured,
    ** it will not be invoked in this case.
    */

  i64 nKey;                 /* Size of pKey, or last integer key */
  void *pKey;               /* Saved key that was cursor last known position */
  Pgno pgnoRoot;            /* The root page of this tree */
  int nOvflAlloc;           /* Allocated size of aOverflow[] array */
  int skipNext;    /* Prev() is noop if negative. Next() is noop if positive.
                   ** Error code if eState==CURSOR_FAULT */
  u8 curFlags;              /* zero or more BTCF_* flags defined below */
  u8 curPagerFlags;         /* Flags to send to sqlite3PagerGet() */
  u8 eState;                /* One of the CURSOR_XXX constants (see below) */
  u8 hints;                 /* As configured by CursorSetHints() */
  /* All fields above are zeroed when the cursor is allocated.  See
  ** sqlite3BtreeCursorZero().  Fields that follow must be manually
  ** initialized. */
  i8 iPage;                 /* Index of current page in apPage */
  u8 curIntKey;             /* Value of apPage[0]->intKey */

    *pDifferentRow = 1;
  }else{
    assert( pCur->skipNext==0 );
    *pDifferentRow = 0;
  }
  return SQLITE_OK;
}

#ifdef SQLITE_ENABLE_CURSOR_HINTS
/*
** Provide hints to the cursor.  The particular hint given (and the type
** and number of the varargs parameters) is determined by the eHintType
** parameter.  See the definitions of the BTREE_HINT_* macros for details.
*/
SQLITE_PRIVATE void sqlite3BtreeCursorHint(BtCursor *pCur, int eHintType, ...){
  /* Used only by system that substitute their own storage engine */
}
#endif

/*
** Provide flag hints to the cursor.
*/
SQLITE_PRIVATE void sqlite3BtreeCursorHintFlags(BtCursor *pCur, unsigned x){
  assert( x==BTREE_SEEK_EQ || x==BTREE_BULKLOAD || x==0 );
  pCur->hints = x;
}


#ifndef SQLITE_OMIT_AUTOVACUUM
/*
** Given a page number of a regular database page, return the page
** number for the pointer-map page that contains the entry for the
** input page number.
**

  assert( pBt->autoVacuum );
  if( key==0 ){
    *pRC = SQLITE_CORRUPT_BKPT;
    return;
  }
  iPtrmap = PTRMAP_PAGENO(pBt, key);
  rc = sqlite3PagerGet(pBt->pPager, iPtrmap, &pDbPage, 0);
  if( rc!=SQLITE_OK ){
    *pRC = rc;
    return;
  }
  offset = PTRMAP_PTROFFSET(iPtrmap, key);
  if( offset<0 ){
    *pRC = SQLITE_CORRUPT_BKPT;

  u8 *pPtrmap;       /* Pointer map page data */
  int offset;        /* Offset of entry in pointer map */
  int rc;

  assert( sqlite3_mutex_held(pBt->mutex) );

  iPtrmap = PTRMAP_PAGENO(pBt, key);
  rc = sqlite3PagerGet(pBt->pPager, iPtrmap, &pDbPage, 0);
  if( rc!=0 ){
    return rc;
  }
  pPtrmap = (u8 *)sqlite3PagerGetData(pDbPage);

  offset = PTRMAP_PTROFFSET(iPtrmap, key);
  if( offset<0 ){

/*
** Convert a DbPage obtained from the pager into a MemPage used by
** the btree layer.
*/
static MemPage *btreePageFromDbPage(DbPage *pDbPage, Pgno pgno, BtShared *pBt){
  MemPage *pPage = (MemPage*)sqlite3PagerGetExtra(pDbPage);
  if( pgno!=pPage->pgno ){
    pPage->aData = sqlite3PagerGetData(pDbPage);
    pPage->pDbPage = pDbPage;
    pPage->pBt = pBt;
    pPage->pgno = pgno;
    pPage->hdrOffset = pgno==1 ? 100 : 0;
  }
  assert( pPage->aData==sqlite3PagerGetData(pDbPage) );
  return pPage; 
}

/*
** Get a page from the pager.  Initialize the MemPage.pBt and
** MemPage.aData elements if needed.  See also: btreeGetUnusedPage().
**

  int flags            /* PAGER_GET_NOCONTENT or PAGER_GET_READONLY */
){
  int rc;
  DbPage *pDbPage;

  assert( flags==0 || flags==PAGER_GET_NOCONTENT || flags==PAGER_GET_READONLY );
  assert( sqlite3_mutex_held(pBt->mutex) );
  rc = sqlite3PagerGet(pBt->pPager, pgno, (DbPage**)&pDbPage, flags);
  if( rc ) return rc;
  *ppPage = btreePageFromDbPage(pDbPage, pgno, pBt);
  return SQLITE_OK;
}

/*
** Retrieve a page from the pager cache. If the requested page is not

  assert( pCur==0 || bReadOnly==pCur->curPagerFlags );
  assert( pCur==0 || pCur->iPage>0 );

  if( pgno>btreePagecount(pBt) ){
    rc = SQLITE_CORRUPT_BKPT;
    goto getAndInitPage_error;
  }
  rc = sqlite3PagerGet(pBt->pPager, pgno, (DbPage**)&pDbPage, bReadOnly);
  if( rc ){
    goto getAndInitPage_error;
  }
  *ppPage = (MemPage*)sqlite3PagerGetExtra(pDbPage);
  if( (*ppPage)->isInit==0 ){
    btreePageFromDbPage(pDbPage, pgno, pBt);
    rc = btreeInitPage(*ppPage);
    if( rc!=SQLITE_OK ){
      releasePage(*ppPage);
      goto getAndInitPage_error;
    }
  }
  assert( (*ppPage)->pgno==pgno );
  assert( (*ppPage)->aData==sqlite3PagerGetData(pDbPage) );

  /* If obtaining a child page for a cursor, we must verify that the page is
  ** compatible with the root page. */

  if( pCur && ((*ppPage)->nCell<1 || (*ppPage)->intKey!=pCur->curIntKey) ){

    rc = SQLITE_CORRUPT_BKPT;
    releasePage(*ppPage);
    goto getAndInitPage_error;
  }
  return SQLITE_OK;

getAndInitPage_error:

#endif

  sqlite3_free(p);
  return SQLITE_OK;
}

/*
** Change the "soft" limit on the number of pages in the cache.
** Unused and unmodified pages will be recycled when the number of
** pages in the cache exceeds this soft limit.  But the size of the
** cache is allowed to grow larger than this limit if it contains




** dirty pages or pages still in active use.




*/
SQLITE_PRIVATE int sqlite3BtreeSetCacheSize(Btree *p, int mxPage){
  BtShared *pBt = p->pBt;
  assert( sqlite3_mutex_held(p->db->mutex) );
  sqlite3BtreeEnter(p);
  sqlite3PagerSetCachesize(pBt->pPager, mxPage);
  sqlite3BtreeLeave(p);
  return SQLITE_OK;
}

/*
** Change the "spill" limit on the number of pages in the cache.
** If the number of pages exceeds this limit during a write transaction,
** the pager might attempt to "spill" pages to the journal early in
** order to free up memory.
**
** The value returned is the current spill size.  If zero is passed
** as an argument, no changes are made to the spill size setting, so
** using mxPage of 0 is a way to query the current spill size.
*/
SQLITE_PRIVATE int sqlite3BtreeSetSpillSize(Btree *p, int mxPage){
  BtShared *pBt = p->pBt;
  int res;
  assert( sqlite3_mutex_held(p->db->mutex) );
  sqlite3BtreeEnter(p);
  res = sqlite3PagerSetSpillsize(pBt->pPager, mxPage);
  sqlite3BtreeLeave(p);
  return res;
}

#if SQLITE_MAX_MMAP_SIZE>0
/*
** Change the limit on the amount of the database file that may be
** memory mapped.
*/
SQLITE_PRIVATE int sqlite3BtreeSetMmapLimit(Btree *p, sqlite3_int64 szMmap){

  struct KeyInfo *pKeyInfo,              /* First arg to comparison function */
  BtCursor *pCur                         /* Space for new cursor */
){
  BtShared *pBt = p->pBt;                /* Shared b-tree handle */
  BtCursor *pX;                          /* Looping over other all cursors */

  assert( sqlite3BtreeHoldsMutex(p) );
  assert( wrFlag==0 
       || wrFlag==BTREE_WRCSR 
       || wrFlag==(BTREE_WRCSR|BTREE_FORDELETE) 
  );

  /* The following assert statements verify that if this is a sharable 
  ** b-tree database, the connection is holding the required table locks, 
  ** and that no other connection has any open cursor that conflicts with 
  ** this lock.  */
  assert( hasSharedCacheTableLock(p, iTable, pKeyInfo!=0, (wrFlag?2:1)) );
  assert( wrFlag==0 || !hasReadConflicts(p, iTable) );

  /* Assert that the caller has opened the required transaction. */
  assert( p->inTrans>TRANS_NONE );
  assert( wrFlag==0 || p->inTrans==TRANS_WRITE );
  assert( pBt->pPage1 && pBt->pPage1->aData );
  assert( wrFlag==0 || (pBt->btsFlags & BTS_READ_ONLY)==0 );

  /* Now that no other errors can occur, finish filling in the BtCursor
  ** variables and link the cursor into the BtShared list.  */
  pCur->pgnoRoot = (Pgno)iTable;
  pCur->iPage = -1;
  pCur->pKeyInfo = pKeyInfo;
  pCur->pBtree = p;
  pCur->pBt = pBt;

  pCur->curFlags = wrFlag ? BTCF_WriteFlag : 0;
  pCur->curPagerFlags = wrFlag ? 0 : PAGER_GET_READONLY;
  /* If there are two or more cursors on the same btree, then all such
  ** cursors *must* have the BTCF_Multiple flag set. */
  for(pX=pBt->pCursor; pX; pX=pX->pNext){
    if( pX->pgnoRoot==(Pgno)iTable ){
      pX->curFlags |= BTCF_Multiple;
      pCur->curFlags |= BTCF_Multiple;

      offset = (offset%ovflSize);
    }

    for( ; rc==SQLITE_OK && amt>0 && nextPage; iIdx++){

      /* If required, populate the overflow page-list cache. */
      if( (pCur->curFlags & BTCF_ValidOvfl)!=0 ){
        assert( pCur->aOverflow[iIdx]==0
                || pCur->aOverflow[iIdx]==nextPage
                || CORRUPT_DB );
        pCur->aOverflow[iIdx] = nextPage;
      }

      if( offset>=ovflSize ){
        /* The only reason to read this page is to obtain the page
        ** number for the next page in the overflow chain. The page
        ** data is not required. So first try to lookup the overflow

          nextPage = get4byte(aWrite);
          memcpy(aWrite, aSave, 4);
        }else
#endif

        {
          DbPage *pDbPage;
          rc = sqlite3PagerGet(pBt->pPager, nextPage, &pDbPage,
              ((eOp&0x01)==0 ? PAGER_GET_READONLY : 0)
          );
          if( rc==SQLITE_OK ){
            aPayload = sqlite3PagerGetData(pDbPage);
            nextPage = get4byte(aPayload);
            rc = copyPayload(&aPayload[offset+4], pBuf, a, (eOp&0x01), pDbPage);
            sqlite3PagerUnref(pDbPage);

**
**     *pRes==0     The cursor is left pointing at an entry that
**                  exactly matches intKey/pIdxKey.
**
**     *pRes>0      The cursor is left pointing at an entry that
**                  is larger than intKey/pIdxKey.
**
** For index tables, the pIdxKey->eqSeen field is set to 1 if there
** exists an entry in the table that exactly matches pIdxKey.  
*/
SQLITE_PRIVATE int sqlite3BtreeMovetoUnpacked(
  BtCursor *pCur,          /* The cursor to be moved */
  UnpackedRecord *pIdxKey, /* Unpacked index key */
  i64 intKey,              /* The table key */
  int biasRight,           /* If true, bias the search to the high end */
  int *pRes                /* Write search results here */

** size of a cell stored within an internal node is always less than 1/4
** of the page-size, the aOvflSpace[] buffer is guaranteed to be large
** enough for all overflow cells.
**
** If aOvflSpace is set to a null pointer, this function returns 
** SQLITE_NOMEM.
*/



static int balance_nonroot(
  MemPage *pParent,               /* Parent page of siblings being balanced */
  int iParentIdx,                 /* Index of "the page" in pParent */
  u8 *aOvflSpace,                 /* page-size bytes of space for parent ovfl */
  int isRoot,                     /* True if pParent is a root-page */
  int bBulk                       /* True if this call is part of a bulk load */
){

  }
  for(i=0; i<nNew; i++){
    releasePage(apNew[i]);
  }

  return rc;
}





/*
** This function is called when the root page of a b-tree structure is
** overfull (has one or more overflow pages).
**
** A new child page is allocated and the contents of the current root

    if( iPage<1 ){
      checkAppendMsg(pCheck,
         "%d of %d pages missing from overflow list starting at %d",
          N+1, expected, iFirst);
      break;
    }
    if( checkRef(pCheck, iPage) ) break;
    if( sqlite3PagerGet(pCheck->pPager, (Pgno)iPage, &pOvflPage, 0) ){
      checkAppendMsg(pCheck, "failed to get page %d", iPage);
      break;
    }
    pOvflData = (unsigned char *)sqlite3PagerGetData(pOvflPage);
    if( isFreeList ){
      int n = get4byte(&pOvflData[4]);
#ifndef SQLITE_OMIT_AUTOVACUUM

  }

  pBt->btsFlags &= ~BTS_NO_WAL;
  return rc;
}

/*









** Return true if the cursor has a hint specified.  This routine is
** only used from within assert() statements
*/
SQLITE_PRIVATE int sqlite3BtreeCursorHasHint(BtCursor *pCsr, unsigned int mask){
  return (pCsr->hints & mask)!=0;
}


/*
** Return true if the given Btree is read-only.
*/
SQLITE_PRIVATE int sqlite3BtreeIsReadonly(Btree *p){
  return (p->pBt->btsFlags & BTS_READ_ONLY)!=0;
}

  ** page. For each iteration, variable iOff is set to the byte offset
  ** of the destination page.
  */
  for(iOff=iEnd-(i64)nSrcPgsz; rc==SQLITE_OK && iOff<iEnd; iOff+=nDestPgsz){
    DbPage *pDestPg = 0;
    Pgno iDest = (Pgno)(iOff/nDestPgsz)+1;
    if( iDest==PENDING_BYTE_PAGE(p->pDest->pBt) ) continue;
    if( SQLITE_OK==(rc = sqlite3PagerGet(pDestPager, iDest, &pDestPg, 0))
     && SQLITE_OK==(rc = sqlite3PagerWrite(pDestPg))
    ){
      const u8 *zIn = &zSrcData[iOff%nSrcPgsz];
      u8 *zDestData = sqlite3PagerGetData(pDestPg);
      u8 *zOut = &zDestData[iOff%nDestPgsz];

      /* Copy the data from the source page into the destination page.

    */
    nSrcPage = (int)sqlite3BtreeLastPage(p->pSrc);
    assert( nSrcPage>=0 );
    for(ii=0; (nPage<0 || ii<nPage) && p->iNext<=(Pgno)nSrcPage && !rc; ii++){
      const Pgno iSrcPg = p->iNext;                 /* Source page number */
      if( iSrcPg!=PENDING_BYTE_PAGE(p->pSrc->pBt) ){
        DbPage *pSrcPg;                             /* Source page object */
        rc = sqlite3PagerGet(pSrcPager, iSrcPg, &pSrcPg,PAGER_GET_READONLY);

        if( rc==SQLITE_OK ){
          rc = backupOnePage(p, iSrcPg, sqlite3PagerGetData(pSrcPg), 0);
          sqlite3PagerUnref(pSrcPg);
        }
      }
      p->iNext++;
    }

          ** the database file in any way, knowing that if a power failure
          ** occurs, the original database will be reconstructed from the 
          ** journal file.  */
          sqlite3PagerPagecount(pDestPager, &nDstPage);
          for(iPg=nDestTruncate; rc==SQLITE_OK && iPg<=(Pgno)nDstPage; iPg++){
            if( iPg!=PENDING_BYTE_PAGE(p->pDest->pBt) ){
              DbPage *pPg;
              rc = sqlite3PagerGet(pDestPager, iPg, &pPg, 0);
              if( rc==SQLITE_OK ){
                rc = sqlite3PagerWrite(pPg);
                sqlite3PagerUnref(pPg);
              }
            }
          }
          if( rc==SQLITE_OK ){
            rc = sqlite3PagerCommitPhaseOne(pDestPager, 0, 1);
          }

          /* Write the extra pages and truncate the database file as required */
          iEnd = MIN(PENDING_BYTE + pgszDest, iSize);
          for(
            iOff=PENDING_BYTE+pgszSrc; 
            rc==SQLITE_OK && iOff<iEnd; 
            iOff+=pgszSrc
          ){
            PgHdr *pSrcPg = 0;
            const Pgno iSrcPg = (Pgno)((iOff/pgszSrc)+1);
            rc = sqlite3PagerGet(pSrcPager, iSrcPg, &pSrcPg, 0);
            if( rc==SQLITE_OK ){
              u8 *zData = sqlite3PagerGetData(pSrcPg);
              rc = sqlite3OsWrite(pFile, zData, pgszSrc, iOff);
            }
            sqlite3PagerUnref(pSrcPg);
          }
          if( rc==SQLITE_OK ){

*/
static void recordFunc(
  sqlite3_context *context,
  int argc,
  sqlite3_value **argv
){
  const int file_format = 1;
  u32 iSerial;                    /* Serial type */
  int nSerial;                    /* Bytes of space for iSerial as varint */
  u32 nVal;                       /* Bytes of space required for argv[0] */
  int nRet;
  sqlite3 *db;
  u8 *aRet;

  UNUSED_PARAMETER( argc );
  iSerial = sqlite3VdbeSerialType(argv[0], file_format, &nVal);
  nSerial = sqlite3VarintLen(iSerial);

  db = sqlite3_context_db_handle(context);

  nRet = 1 + nSerial + nVal;
  aRet = sqlite3DbMallocRaw(db, nRet);
  if( aRet==0 ){
    sqlite3_result_error_nomem(context);
  }else{

**
**    p1, p2, p3      Operands
**
** Use the sqlite3VdbeResolveLabel() function to fix an address and
** the sqlite3VdbeChangeP4() function to change the value of the P4
** operand.
*/
static SQLITE_NOINLINE int growOp3(Vdbe *p, int op, int p1, int p2, int p3){
  assert( p->pParse->nOpAlloc<=p->nOp );
  if( growOpArray(p, 1) ) return 1;
  assert( p->pParse->nOpAlloc>p->nOp );
  return sqlite3VdbeAddOp3(p, op, p1, p2, p3);
}
SQLITE_PRIVATE int sqlite3VdbeAddOp3(Vdbe *p, int op, int p1, int p2, int p3){
  int i;
  VdbeOp *pOp;

  i = p->nOp;
  assert( p->magic==VDBE_MAGIC_INIT );
  assert( op>0 && op<0xff );
  if( p->pParse->nOpAlloc<=i ){

    return growOp3(p, op, p1, p2, p3);

  }
  p->nOp++;
  pOp = &p->aOp[i];
  pOp->opcode = (u8)op;
  pOp->p5 = 0;
  pOp->p1 = p1;
  pOp->p2 = p2;

        sqlite3DbFree(db, p4);
        break;
      }
      case P4_KEYINFO: {
        if( db->pnBytesFreed==0 ) sqlite3KeyInfoUnref((KeyInfo*)p4);
        break;
      }
#ifdef SQLITE_ENABLE_CURSOR_HINTS
      case P4_EXPR: {
        sqlite3ExprDelete(db, (Expr*)p4);
        break;
      }
#endif
      case P4_MPRINTF: {
        if( db->pnBytesFreed==0 ) sqlite3_free(p4);
        break;
      }
      case P4_FUNCDEF: {
        freeEphemeralFunction(db, (FuncDef*)p4);
        break;

SQLITE_PRIVATE void sqlite3VdbeChangeToNoop(Vdbe *p, int addr){
  if( addr<p->nOp ){
    VdbeOp *pOp = &p->aOp[addr];
    sqlite3 *db = p->db;
    freeP4(db, pOp->p4type, pOp->p4.p);
    memset(pOp, 0, sizeof(pOp[0]));
    pOp->opcode = OP_Noop;

  }
}

/*
** If the last opcode is "op" and it is not a jump destination,
** then remove it.  Return true if and only if an opcode was removed.
*/

    pOp->p4type = P4_INT32;
  }else if( zP4==0 ){
    pOp->p4.p = 0;
    pOp->p4type = P4_NOTUSED;
  }else if( n==P4_KEYINFO ){
    pOp->p4.p = (void*)zP4;
    pOp->p4type = P4_KEYINFO;
#ifdef SQLITE_ENABLE_CURSOR_HINTS
  }else if( n==P4_EXPR ){
    /* Responsibility for deleting the Expr tree is handed over to the
    ** VDBE by this operation.  The caller should have already invoked
    ** sqlite3ExprDup() or whatever other routine is needed to make a 
    ** private copy of the tree. */
    pOp->p4.pExpr = (Expr*)zP4;
    pOp->p4type = P4_EXPR;
#endif
  }else if( n==P4_VTAB ){
    pOp->p4.p = (void*)zP4;
    pOp->p4type = P4_VTAB;
    sqlite3VtabLock((VTable *)zP4);
    assert( ((VTable *)zP4)->db==p->db );
  }else if( n<0 ){
    pOp->p4.p = (void*)zP4;

    zTemp[0] = 0;
    jj = 0;
  }
  return jj;
}
#endif /* SQLITE_DEBUG */

#if VDBE_DISPLAY_P4 && defined(SQLITE_ENABLE_CURSOR_HINTS)
/*
** Translate the P4.pExpr value for an OP_CursorHint opcode into text
** that can be displayed in the P4 column of EXPLAIN output.
*/
static int displayP4Expr(int nTemp, char *zTemp, Expr *pExpr){
  const char *zOp = 0;
  int n;
  switch( pExpr->op ){
    case TK_STRING:
      sqlite3_snprintf(nTemp, zTemp, "%Q", pExpr->u.zToken);
      break;
    case TK_INTEGER:
      sqlite3_snprintf(nTemp, zTemp, "%d", pExpr->u.iValue);
      break;
    case TK_NULL:
      sqlite3_snprintf(nTemp, zTemp, "NULL");
      break;
    case TK_REGISTER: {
      sqlite3_snprintf(nTemp, zTemp, "r[%d]", pExpr->iTable);
      break;
    }
    case TK_COLUMN: {
      if( pExpr->iColumn<0 ){
        sqlite3_snprintf(nTemp, zTemp, "rowid");
      }else{
        sqlite3_snprintf(nTemp, zTemp, "c%d", (int)pExpr->iColumn);
      }
      break;
    }
    case TK_LT:      zOp = "LT";      break;
    case TK_LE:      zOp = "LE";      break;
    case TK_GT:      zOp = "GT";      break;
    case TK_GE:      zOp = "GE";      break;
    case TK_NE:      zOp = "NE";      break;
    case TK_EQ:      zOp = "EQ";      break;
    case TK_IS:      zOp = "IS";      break;
    case TK_ISNOT:   zOp = "ISNOT";   break;
    case TK_AND:     zOp = "AND";     break;
    case TK_OR:      zOp = "OR";      break;
    case TK_PLUS:    zOp = "ADD";     break;
    case TK_STAR:    zOp = "MUL";     break;
    case TK_MINUS:   zOp = "SUB";     break;
    case TK_REM:     zOp = "REM";     break;
    case TK_BITAND:  zOp = "BITAND";  break;
    case TK_BITOR:   zOp = "BITOR";   break;
    case TK_SLASH:   zOp = "DIV";     break;
    case TK_LSHIFT:  zOp = "LSHIFT";  break;
    case TK_RSHIFT:  zOp = "RSHIFT";  break;
    case TK_CONCAT:  zOp = "CONCAT";  break;
    case TK_UMINUS:  zOp = "MINUS";   break;
    case TK_UPLUS:   zOp = "PLUS";    break;
    case TK_BITNOT:  zOp = "BITNOT";  break;
    case TK_NOT:     zOp = "NOT";     break;
    case TK_ISNULL:  zOp = "ISNULL";  break;
    case TK_NOTNULL: zOp = "NOTNULL"; break;

    default:
      sqlite3_snprintf(nTemp, zTemp, "%s", "expr");
      break;
  }

  if( zOp ){
    sqlite3_snprintf(nTemp, zTemp, "%s(", zOp);
    n = sqlite3Strlen30(zTemp);
    n += displayP4Expr(nTemp-n, zTemp+n, pExpr->pLeft);
    if( n<nTemp-1 && pExpr->pRight ){
      zTemp[n++] = ',';
      n += displayP4Expr(nTemp-n, zTemp+n, pExpr->pRight);
    }
    sqlite3_snprintf(nTemp-n, zTemp+n, ")");
  }
  return sqlite3Strlen30(zTemp);
}
#endif /* VDBE_DISPLAY_P4 && defined(SQLITE_ENABLE_CURSOR_HINTS) */


#if VDBE_DISPLAY_P4
/*
** Compute a string that describes the P4 parameter for an opcode.
** Use zTemp for any required temporary buffer space.
*/
static char *displayP4(Op *pOp, char *zTemp, int nTemp){
  char *zP4 = zTemp;
  assert( nTemp>=20 );

        i += n;
      }
      zTemp[i++] = ')';
      zTemp[i] = 0;
      assert( i<nTemp );
      break;
    }
#ifdef SQLITE_ENABLE_CURSOR_HINTS
    case P4_EXPR: {
      displayP4Expr(nTemp, zTemp, pOp->p4.pExpr);
      break;
    }
#endif
    case P4_COLLSEQ: {
      CollSeq *pColl = pOp->p4.pColl;
      sqlite3_snprintf(nTemp, zTemp, "(%.20s)", pColl->zName);
      break;
    }
    case P4_FUNCDEF: {
      FuncDef *pDef = pOp->p4.pFunc;

        zTemp[0] = 0;
      }
    }
  }
  assert( zP4!=0 );
  return zP4;
}
#endif /* VDBE_DISPLAY_P4 */

/*
** Declare to the Vdbe that the BTree object at db->aDb[i] is used.
**
** The prepared statements need to know in advance the complete set of
** attached databases that will be use.  A mask of these databases
** is maintained in p->btreeMask.  The p->lockMask value is the subset of

    pMem->u.i = pOp->p2;                          /* P2 */
    pMem++;

    pMem->flags = MEM_Int;
    pMem->u.i = pOp->p3;                          /* P3 */
    pMem++;

    if( sqlite3VdbeMemClearAndResize(pMem, 100) ){ /* P4 */
      assert( p->db->mallocFailed );
      return SQLITE_ERROR;
    }
    pMem->flags = MEM_Str|MEM_Term;
    zP4 = displayP4(pOp, pMem->z, pMem->szMalloc);
    if( zP4!=pMem->z ){
      sqlite3VdbeMemSetStr(pMem, zP4, -1, SQLITE_UTF8, 0);
    }else{
      assert( pMem->z!=0 );
      pMem->n = sqlite3Strlen30(pMem->z);
      pMem->enc = SQLITE_UTF8;
    }

** 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->pBt==0 || pCx->eCurType==CURTYPE_BTREE );
  switch( pCx->eCurType ){
    case CURTYPE_SORTER: {
      sqlite3VdbeSorterClose(p->db, pCx);
      break;
    }
    case CURTYPE_BTREE: {
      if( pCx->pBt ){
        sqlite3BtreeClose(pCx->pBt);
        /* 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;
    }
#ifndef SQLITE_OMIT_VIRTUALTABLE
    case CURTYPE_VTAB: {
      sqlite3_vtab_cursor *pVCur = pCx->uc.pVCur;
      const sqlite3_module *pModule = pVCur->pVtab->pModule;
      assert( pVCur->pVtab->nRef>0 );
      pVCur->pVtab->nRef--;
      pModule->xClose(pVCur);
      break;
    }
#endif
  }
}

/*
** Close all cursors in the current frame.
*/
static void closeCursorsInFrame(Vdbe *p){
  if( p->apCsr ){

static int SQLITE_NOINLINE handleDeferredMoveto(VdbeCursor *p){
  int res, rc;
#ifdef SQLITE_TEST
  extern int sqlite3_search_count;
#endif
  assert( p->deferredMoveto );
  assert( p->isTable );
  assert( p->eCurType==CURTYPE_BTREE );
  rc = sqlite3BtreeMovetoUnpacked(p->uc.pCursor, 0, p->movetoTarget, 0, &res);
  if( rc ) return rc;
  if( res!=0 ) return SQLITE_CORRUPT_BKPT;
#ifdef SQLITE_TEST
  sqlite3_search_count++;
#endif
  p->deferredMoveto = 0;
  p->cacheStatus = CACHE_STALE;
  return SQLITE_OK;
}

/*
** Something has moved cursor "p" out of place.  Maybe the row it was
** pointed to was deleted out from under it.  Or maybe the btree was
** rebalanced.  Whatever the cause, try to restore "p" to the place it
** is supposed to be pointing.  If the row was deleted out from under the
** cursor, set the cursor to point to a NULL row.
*/
static int SQLITE_NOINLINE handleMovedCursor(VdbeCursor *p){
  int isDifferentRow, rc;
  assert( p->eCurType==CURTYPE_BTREE );
  assert( p->uc.pCursor!=0 );
  assert( sqlite3BtreeCursorHasMoved(p->uc.pCursor) );
  rc = sqlite3BtreeCursorRestore(p->uc.pCursor, &isDifferentRow);
  p->cacheStatus = CACHE_STALE;
  if( isDifferentRow ) p->nullRow = 1;
  return rc;
}

/*
** Check to ensure that the cursor is valid.  Restore the cursor
** if need be.  Return any I/O error from the restore operation.
*/
SQLITE_PRIVATE int sqlite3VdbeCursorRestore(VdbeCursor *p){
  assert( p->eCurType==CURTYPE_BTREE );
  if( sqlite3BtreeCursorHasMoved(p->uc.pCursor) ){
    return handleMovedCursor(p);
  }
  return SQLITE_OK;
}

/*
** Make sure the cursor p is ready to read or write the row to which it
** was last positioned.  Return an error code if an OOM fault or I/O error
** prevents us from positioning the cursor to its correct position.
**
** If a MoveTo operation is pending on the given cursor, then do that
** MoveTo now.  If no move is pending, check to see if the row has been
** deleted out from under the cursor and if it has, mark the row as
** a NULL row.
**
** If the cursor is already pointing to the correct row and that row has
** not been deleted out from under the cursor, then this routine is a no-op.
*/
SQLITE_PRIVATE int sqlite3VdbeCursorMoveto(VdbeCursor *p){
  if( p->eCurType==CURTYPE_BTREE ){
    if( p->deferredMoveto ){
      return handleDeferredMoveto(p);
    }
    if( sqlite3BtreeCursorHasMoved(p->uc.pCursor) ){
      return handleMovedCursor(p);
    }
  }
  return SQLITE_OK;
}

/*
** The following functions:
**

** The 8 and 9 types were added in 3.3.0, file format 4.  Prior versions
** of SQLite will not understand those serial types.
*/

/*
** Return the serial-type for the value stored in pMem.
*/
SQLITE_PRIVATE u32 sqlite3VdbeSerialType(Mem *pMem, int file_format, u32 *pLen){
  int flags = pMem->flags;
  u32 n;

  assert( pLen!=0 );
  if( flags&MEM_Null ){
    *pLen = 0;
    return 0;
  }
  if( flags&MEM_Int ){
    /* Figure out whether to use 1, 2, 4, 6 or 8 bytes. */
#   define MAX_6BYTE ((((i64)0x00008000)<<32)-1)
    i64 i = pMem->u.i;
    u64 u;
    if( i<0 ){
      u = ~i;
    }else{
      u = i;
    }
    if( u<=127 ){
      if( (i&1)==i && file_format>=4 ){
        *pLen = 0;
        return 8+(u32)u;
      }else{
        *pLen = 1;
        return 1;
      }
    }
    if( u<=32767 ){ *pLen = 2; return 2; }
    if( u<=8388607 ){ *pLen = 3; return 3; }
    if( u<=2147483647 ){ *pLen = 4; return 4; }
    if( u<=MAX_6BYTE ){ *pLen = 6; return 5; }
    *pLen = 8;
    return 6;
  }
  if( flags&MEM_Real ){
    *pLen = 8;
    return 7;
  }
  assert( pMem->db->mallocFailed || flags&(MEM_Str|MEM_Blob) );
  assert( pMem->n>=0 );
  n = (u32)pMem->n;
  if( flags & MEM_Zero ){
    n += pMem->u.nZero;
  }
  *pLen = n;
  return ((n*2) + 12 + ((flags&MEM_Str)!=0));
}

/*
** The sizes for serial types less than 128
*/
static const u8 sqlite3SmallTypeSizes[] = {
        /*  0   1   2   3   4   5   6   7   8   9 */   
/*   0 */   0,  1,  2,  3,  4,  6,  8,  8,  0,  0,
/*  10 */   0,  0,  0,  0,  1,  1,  2,  2,  3,  3,
/*  20 */   4,  4,  5,  5,  6,  6,  7,  7,  8,  8,
/*  30 */   9,  9, 10, 10, 11, 11, 12, 12, 13, 13,
/*  40 */  14, 14, 15, 15, 16, 16, 17, 17, 18, 18,
/*  50 */  19, 19, 20, 20, 21, 21, 22, 22, 23, 23,
/*  60 */  24, 24, 25, 25, 26, 26, 27, 27, 28, 28,
/*  70 */  29, 29, 30, 30, 31, 31, 32, 32, 33, 33,
/*  80 */  34, 34, 35, 35, 36, 36, 37, 37, 38, 38,
/*  90 */  39, 39, 40, 40, 41, 41, 42, 42, 43, 43,
/* 100 */  44, 44, 45, 45, 46, 46, 47, 47, 48, 48,
/* 110 */  49, 49, 50, 50, 51, 51, 52, 52, 53, 53,
/* 120 */  54, 54, 55, 55, 56, 56, 57, 57
};

/*
** Return the length of the data corresponding to the supplied serial-type.
*/
SQLITE_PRIVATE u32 sqlite3VdbeSerialTypeLen(u32 serial_type){
  if( serial_type>=128 ){
    return (serial_type-12)/2;
  }else{
    assert( serial_type<12 
            || sqlite3SmallTypeSizes[serial_type]==(serial_type - 12)/2 );
    return sqlite3SmallTypeSizes[serial_type];
  }
}
SQLITE_PRIVATE u8 sqlite3VdbeOneByteSerialTypeLen(u8 serial_type){
  assert( serial_type<128 );
  return sqlite3SmallTypeSizes[serial_type];  
}

/*
** If we are on an architecture with mixed-endian floating 
** points (ex: ARM7) then swap the lower 4 bytes with the 
** upper 4 bytes.  Return the result.
**

      testcase( pMem->u.i<0 );
      return 3;
    }
    case 4: { /* 4-byte signed integer */
      /* EVIDENCE-OF: R-01849-26079 Value is a big-endian 32-bit
      ** twos-complement integer. */
      pMem->u.i = FOUR_BYTE_INT(buf);
#ifdef __HP_cc 
      /* Work around a sign-extension bug in the HP compiler for HP/UX */
      if( buf[0]&0x80 ) pMem->u.i |= 0xffffffff80000000LL;
#endif
      pMem->flags = MEM_Int;
      testcase( pMem->u.i<0 );
      return 4;
    }
    case 5: { /* 6-byte signed integer */
      /* EVIDENCE-OF: R-50385-09674 Value is a big-endian 48-bit
      ** twos-complement integer. */

*/
static SQLITE_NOINLINE int sqlite3BlobCompare(const Mem *pB1, const Mem *pB2){
  int c = memcmp(pB1->z, pB2->z, pB1->n>pB2->n ? pB2->n : pB1->n);
  if( c ) return c;
  return pB1->n - pB2->n;
}

/*
** Do a comparison between a 64-bit signed integer and a 64-bit floating-point
** number.  Return negative, zero, or positive if the first (i64) is less than,
** equal to, or greater than the second (double).
*/
static int sqlite3IntFloatCompare(i64 i, double r){
  if( sizeof(LONGDOUBLE_TYPE)>8 ){
    LONGDOUBLE_TYPE x = (LONGDOUBLE_TYPE)i;
    if( x<r ) return -1;
    if( x>r ) return +1;
    return 0;
  }else{
    i64 y;
    double s;
    if( r<-9223372036854775808.0 ) return +1;
    if( r>9223372036854775807.0 ) return -1;
    y = (i64)r;
    if( i<y ) return -1;
    if( i>y ){
      if( y==SMALLEST_INT64 && r>0.0 ) return -1;
      return +1;
    }
    s = (double)i;
    if( s<r ) return -1;
    if( s>r ) return +1;
    return 0;
  }
}

/*
** Compare the values contained by the two memory cells, returning
** negative, zero or positive if pMem1 is less than, equal to, or greater
** than pMem2. Sorting order is NULL's first, followed by numbers (integers
** and reals) sorted numerically, followed by text ordered by the collating
** sequence pColl and finally blob's ordered by memcmp().

  /* If one value is NULL, it is less than the other. If both values
  ** are NULL, return 0.
  */
  if( combined_flags&MEM_Null ){
    return (f2&MEM_Null) - (f1&MEM_Null);
  }

  /* At least one of the two values is a number


  */
  if( combined_flags&(MEM_Int|MEM_Real) ){

    if( (f1 & f2 & MEM_Int)!=0 ){
      if( pMem1->u.i < pMem2->u.i ) return -1;
      if( pMem1->u.i > pMem2->u.i ) return +1;
      return 0;
    }
    if( (f1 & f2 & MEM_Real)!=0 ){
      if( pMem1->u.r < pMem2->u.r ) return -1;
      if( pMem1->u.r > pMem2->u.r ) return +1;
      return 0;
    }
    if( (f1&MEM_Int)!=0 ){
      if( (f2&MEM_Real)!=0 ){
        return sqlite3IntFloatCompare(pMem1->u.i, pMem2->u.r);
      }else{
        return -1;
      }
    }
    if( (f1&MEM_Real)!=0 ){

      if( (f2&MEM_Int)!=0 ){
        return -sqlite3IntFloatCompare(pMem2->u.i, pMem1->u.r);
      }else{
        return -1;
      }


    }
    return +1;
  }

  /* If one value is a string and the other is a blob, the string is less.
  ** If both are strings, compare using the collating functions.
  */
  if( combined_flags&MEM_Str ){
    if( (f1 & MEM_Str)==0 ){

      serial_type = aKey1[idx1];
      testcase( serial_type==12 );
      if( serial_type>=10 ){
        rc = +1;
      }else if( serial_type==0 ){
        rc = -1;
      }else if( serial_type==7 ){

        sqlite3VdbeSerialGet(&aKey1[d1], serial_type, &mem1);

        rc = -sqlite3IntFloatCompare(pRhs->u.i, mem1.u.r);



      }else{
        i64 lhs = vdbeRecordDecodeInt(serial_type, &aKey1[d1]);
        i64 rhs = pRhs->u.i;
        if( lhs<rhs ){
          rc = -1;
        }else if( lhs>rhs ){
          rc = +1;

        ** numbers). Types 10 and 11 are currently "reserved for future 
        ** use", so it doesn't really matter what the results of comparing
        ** them to numberic values are.  */
        rc = +1;
      }else if( serial_type==0 ){
        rc = -1;
      }else{


        sqlite3VdbeSerialGet(&aKey1[d1], serial_type, &mem1);
        if( serial_type==7 ){
          if( mem1.u.r<pRhs->u.r ){




            rc = -1;
          }else if( mem1.u.r>pRhs->u.r ){
            rc = +1;
          }
        }else{
          rc = sqlite3IntFloatCompare(mem1.u.i, pRhs->u.r);
        }
      }
    }

    /* RHS is a string */
    else if( pRhs->flags & MEM_Str ){
      getVarint32(&aKey1[idx1], serial_type);

  /* rc==0 here means that one or both of the keys ran out of fields and
  ** all the fields up to that point were equal. Return the default_rc
  ** value.  */
  assert( CORRUPT_DB 
       || vdbeRecordCompareDebug(nKey1, pKey1, pPKey2, pPKey2->default_rc) 
       || pKeyInfo->db->mallocFailed
  );
  pPKey2->eqSeen = 1;
  return pPKey2->default_rc;
}
SQLITE_PRIVATE int sqlite3VdbeRecordCompare(
  int nKey1, const void *pKey1,   /* Left key */
  UnpackedRecord *pPKey2          /* Right key */
){
  return sqlite3VdbeRecordCompareWithSkip(nKey1, pKey1, pPKey2, 0);

    /* The first fields of the two keys are equal. Compare the trailing 
    ** fields.  */
    res = sqlite3VdbeRecordCompareWithSkip(nKey1, pKey1, pPKey2, 1);
  }else{
    /* The first fields of the two keys are equal and there are no trailing
    ** fields. Return pPKey2->default_rc in this case. */
    res = pPKey2->default_rc;
    pPKey2->eqSeen = 1;
  }

  assert( vdbeRecordCompareDebug(nKey1, pKey1, pPKey2, res) );
  return res;
}

/*
** This function is an optimized version of sqlite3VdbeRecordCompare() 
** that (a) the first field of pPKey2 is a string, that (b) the first field
** uses the collation sequence BINARY and (c) that the size-of-header varint 
** at the start of (pKey1/nKey1) fits in a single byte.
*/
static int vdbeRecordCompareString(
  int nKey1, const void *pKey1, /* Left key */
  UnpackedRecord *pPKey2        /* Right key */
){
  const u8 *aKey1 = (const u8*)pKey1;
  int serial_type;
  int res;

  assert( pPKey2->aMem[0].flags & MEM_Str );
  vdbeAssertFieldCountWithinLimits(nKey1, pKey1, pPKey2->pKeyInfo);
  getVarint32(&aKey1[1], serial_type);
  if( serial_type<12 ){
    res = pPKey2->r1;      /* (pKey1/nKey1) is a number or a null */
  }else if( !(serial_type & 0x01) ){ 
    res = pPKey2->r2;      /* (pKey1/nKey1) is a blob */
  }else{

    if( res==0 ){
      res = nStr - pPKey2->aMem[0].n;
      if( res==0 ){
        if( pPKey2->nField>1 ){
          res = sqlite3VdbeRecordCompareWithSkip(nKey1, pKey1, pPKey2, 1);
        }else{
          res = pPKey2->default_rc;
          pPKey2->eqSeen = 1;
        }
      }else if( res>0 ){
        res = pPKey2->r2;
      }else{
        res = pPKey2->r1;
      }
    }else if( res>0 ){

  sqlite3 *db,                     /* Database connection */
  VdbeCursor *pC,                  /* The cursor to compare against */
  UnpackedRecord *pUnpacked,       /* Unpacked version of key */
  int *res                         /* Write the comparison result here */
){
  i64 nCellKey = 0;
  int rc;
  BtCursor *pCur;
  Mem m;

  assert( pC->eCurType==CURTYPE_BTREE );
  pCur = pC->uc.pCursor;
  assert( sqlite3BtreeCursorIsValid(pCur) );
  VVA_ONLY(rc =) sqlite3BtreeKeySize(pCur, &nCellKey);
  assert( rc==SQLITE_OK );    /* pCur is always valid so KeySize cannot fail */
  /* 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, 1, &m);
  if( rc ){
    return rc;
  }
  *res = sqlite3VdbeRecordCompare(m.n, m.z, pUnpacked);
  sqlite3VdbeMemRelease(&m);
  return SQLITE_OK;
}

** converts an MEM_Ephem string into a string with P.z==P.zMalloc.
*/
#define Deephemeralize(P) \
   if( ((P)->flags&MEM_Ephem)!=0 \
       && sqlite3VdbeMemMakeWriteable(P) ){ goto no_mem;}

/* Return true if the cursor was opened using the OP_OpenSorter opcode. */
#define isSorter(x) ((x)->eCurType==CURTYPE_SORTER)

/*
** Allocate VdbeCursor number iCur.  Return a pointer to it.  Return NULL
** if we run out of memory.
*/
static VdbeCursor *allocateCursor(
  Vdbe *p,              /* The virtual machine */
  int iCur,             /* Index of the new VdbeCursor */
  int nField,           /* Number of fields in the table or index */
  int iDb,              /* Database the cursor belongs to, or -1 */
  u8 eCurType           /* Type of the new cursor */
){
  /* Find the memory cell that will be used to store the blob of memory
  ** required for this VdbeCursor structure. It is convenient to use a 
  ** vdbe memory cell to manage the memory allocation required for a
  ** VdbeCursor structure for the following reasons:
  **
  **   * Sometimes cursor numbers are used for a couple of different

  */
  Mem *pMem = &p->aMem[p->nMem-iCur];

  int nByte;
  VdbeCursor *pCx = 0;
  nByte = 
      ROUND8(sizeof(VdbeCursor)) + 2*sizeof(u32)*nField + 
      (eCurType==CURTYPE_BTREE?sqlite3BtreeCursorSize():0);

  assert( iCur<p->nCursor );
  if( p->apCsr[iCur] ){
    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, sizeof(VdbeCursor));
    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];
      sqlite3BtreeCursorZero(pCx->uc.pCursor);
    }
  }
  return pCx;
}

/*
** Try to convert a value into a numeric representation if we can

  return 1;
}
#endif

/*
** Return the register of pOp->p2 after first preparing it to be
** overwritten with an integer value.
*/
static SQLITE_NOINLINE Mem *out2PrereleaseWithClear(Mem *pOut){
  sqlite3VdbeMemSetNull(pOut);
  pOut->flags = MEM_Int;
  return pOut;
}
static Mem *out2Prerelease(Vdbe *p, VdbeOp *pOp){
  Mem *pOut;
  assert( pOp->p2>0 );
  assert( pOp->p2<=(p->nMem-p->nCursor) );
  pOut = &p->aMem[pOp->p2];
  memAboutToChange(p, pOut);
  if( VdbeMemDynamic(pOut) ){
    return out2PrereleaseWithClear(pOut);
  }else{
    pOut->flags = MEM_Int;
    return pOut;
  }
}


/*
** Execute as much of a VDBE program as we can.
** This is the core of sqlite3_step().  
*/

  assert( pOp->p4.z!=0 );
  pOut = out2Prerelease(p, pOp);
  pOut->flags = MEM_Str|MEM_Static|MEM_Term;
  pOut->z = pOp->p4.z;
  pOut->n = pOp->p1;
  pOut->enc = encoding;
  UPDATE_MAX_BLOBSIZE(pOut);
#ifndef SQLITE_LIKE_DOESNT_MATCH_BLOBS
  if( pOp->p5 ){
    assert( pOp->p3>0 );
    assert( pOp->p3<=(p->nMem-p->nCursor) );
    pIn3 = &aMem[pOp->p3];
    assert( pIn3->flags & MEM_Int );
    if( pIn3->u.i ) pOut->flags = MEM_Blob|MEM_Static|MEM_Term;
  }
#endif
  break;
}

/* Opcode: Null P1 P2 P3 * *
** Synopsis:  r[P2..P3]=NULL
**
** Write a NULL into registers P2.  If P3 greater than P2, then also write

  assert( pOut!=pIn1 );
  sqlite3VdbeMemShallowCopy(pOut, pIn1, MEM_Ephem);
#ifdef SQLITE_DEBUG
  if( pOut->pScopyFrom==0 ) pOut->pScopyFrom = pIn1;
#endif
  break;
}

/* Opcode: IntCopy P1 P2 * * *
** Synopsis: r[P2]=r[P1]
**
** Transfer the integer value held in register P1 into register P2.
**
** This is an optimized version of SCopy that works only for integer
** values.
*/
case OP_IntCopy: {            /* out2 */
  pIn1 = &aMem[pOp->p1];
  assert( (pIn1->flags & MEM_Int)!=0 );
  pOut = &aMem[pOp->p2];
  sqlite3VdbeMemSetInt64(pOut, pIn1->u.i);
  break;
}

/* Opcode: ResultRow P1 P2 * * *
** Synopsis:  output=r[P1@P2]
**
** The registers P1 through P1+P2-1 contain a single row of
** results. This opcode causes the sqlite3_step() call to terminate
** with an SQLITE_ROW return code and it sets up the sqlite3_stmt

  int i;             /* Loop counter */
  Mem *pDest;        /* Where to write the extracted value */
  Mem sMem;          /* For storing the record being decoded */
  const u8 *zData;   /* Part of the record being decoded */
  const u8 *zHdr;    /* Next unparsed byte of the header */
  const u8 *zEndHdr; /* Pointer to first byte after the header */
  u32 offset;        /* Offset into the data */
  u64 offset64;      /* 64-bit offset */
  u32 avail;         /* Number of bytes of available data */
  u32 t;             /* A type code from the record header */
  u16 fx;            /* pDest->flags value */
  Mem *pReg;         /* PseudoTable input register */

  p2 = pOp->p2;
  assert( pOp->p3>0 && pOp->p3<=(p->nMem-p->nCursor) );
  pDest = &aMem[pOp->p3];
  memAboutToChange(p, pDest);
  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
  pC = p->apCsr[pOp->p1];
  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 );
  pCrsr = pC->uc.pCursor;



  /* If the cursor cache is stale, bring it up-to-date */
  rc = sqlite3VdbeCursorMoveto(pC);
  if( rc ) goto abort_due_to_error;
  if( pC->cacheStatus!=p->cacheCtr ){
    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{
      assert( pC->eCurType==CURTYPE_BTREE );
      assert( pCrsr );
      if( pC->isTable==0 ){
        assert( sqlite3BtreeCursorIsValid(pCrsr) );
        VVA_ONLY(rc =) sqlite3BtreeKeySize(pCrsr, &payloadSize64);
        assert( rc==SQLITE_OK ); /* True because of CursorMoveto() call above */
        /* sqlite3BtreeParseCellPtr() uses getVarint32() to extract the
        ** payload size, so it is impossible for payloadSize64 to be
        ** larger than 32 bits. */
        assert( (payloadSize64 & SQLITE_MAX_U32)==(u64)payloadSize64 );
        pC->aRow = sqlite3BtreeKeyFetch(pCrsr, &avail);
        pC->payloadSize = (u32)payloadSize64;
      }else{
        assert( sqlite3BtreeCursorIsValid(pCrsr) );
        VVA_ONLY(rc =) sqlite3BtreeDataSize(pCrsr, &pC->payloadSize);
        assert( rc==SQLITE_OK );   /* DataSize() cannot fail */
        pC->aRow = sqlite3BtreeDataFetch(pCrsr, &avail);
      }
      assert( avail<=65536 );  /* Maximum page size is 64KiB */
      if( pC->payloadSize <= (u32)avail ){
        pC->szRow = pC->payloadSize;
      }else if( pC->payloadSize > (u32)db->aLimit[SQLITE_LIMIT_LENGTH] ){
        goto too_big;
      }else{
        pC->szRow = avail;



      }
    }
    pC->cacheStatus = p->cacheCtr;
    pC->iHdrOffset = getVarint32(pC->aRow, offset);
    pC->nHdrParsed = 0;
    aOffset[0] = offset;















    if( avail<offset ){
      /* pC->aRow does not have to hold the entire row, but it does at least
      ** need to cover the header of the record.  If pC->aRow does not contain
      ** the complete header, then set it to zero, forcing the header to be
      ** dynamically allocated. */
      pC->aRow = 0;
      pC->szRow = 0;

      /* Make sure a corrupt database has not given us an oversize header.
      ** Do this now to avoid an oversize memory allocation.
      **
      ** Type entries can be between 1 and 5 bytes each.  But 4 and 5 byte
      ** types use so much data space that there can only be 4096 and 32 of
      ** them, respectively.  So the maximum header length results from a
      ** 3-byte type for each of the maximum of 32768 columns plus three
      ** extra bytes for the header length itself.  32768*3 + 3 = 98307.
      */
      if( offset > 98307 || offset > pC->payloadSize ){
        rc = SQLITE_CORRUPT_BKPT;
        goto op_column_error;
      }
    }

    /* The following goto is an optimization.  It can be omitted and
    ** everything will still work.  But OP_Column is measurably faster
    ** by skipping the subsequent conditional, which is always true.
    */
    assert( pC->nHdrParsed<=p2 );         /* Conditional skipped */

    ** to extract additional fields up through the p2+1-th field 
    */
    op_column_read_header:
    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(pCrsr, 0, aOffset[0], !pC->isTable, &sMem);

        if( rc!=SQLITE_OK ) goto op_column_error;


        zData = (u8*)sMem.z;
      }else{
        zData = pC->aRow;
      }
  
      /* Fill in pC->aType[i] and aOffset[i] values through the p2-th field. */
      i = pC->nHdrParsed;
      offset64 = aOffset[i];
      zHdr = zData + pC->iHdrOffset;
      zEndHdr = zData + aOffset[0];
      assert( i<=p2 && zHdr<zEndHdr );
      do{

        if( (t = zHdr[0])<0x80 ){
          zHdr++;
          offset64 += sqlite3VdbeOneByteSerialTypeLen(t);
        }else{
          zHdr += sqlite3GetVarint32(zHdr, &t);


          offset64 += sqlite3VdbeSerialTypeLen(t);




        }
        pC->aType[i++] = t;
        aOffset[i] = (u32)(offset64 & 0xffffffff);
      }while( i<=p2 && zHdr<zEndHdr );
      pC->nHdrParsed = i;
      pC->iHdrOffset = (u32)(zHdr - zData);
      if( pC->aRow==0 ) sqlite3VdbeMemRelease(&sMem);



  
      /* The record is corrupt if any of the following are true:
      ** (1) the bytes of the header extend past the declared header size

      ** (2) the entire header was used but not all data was used

      ** (3) the end of the data extends beyond the end of the record.

      */
      if( (zHdr>=zEndHdr && (zHdr>zEndHdr || offset64!=pC->payloadSize))
       || (offset64 > pC->payloadSize)
      ){
        rc = SQLITE_CORRUPT_BKPT;
        goto op_column_error;
      }
    }

    /* If after trying to extract new entries from the header, nHdrParsed is
    ** still not up to p2, that means that the record has fewer than p2
    ** columns.  So the result will be either the default value or a NULL.
    */
    if( pC->nHdrParsed<=p2 ){
      if( pOp->p4type==P4_MEM ){
        sqlite3VdbeMemShallowCopy(pDest, pOp->p4.pMem, MEM_Static);
      }else{
        sqlite3VdbeMemSetNull(pDest);
      }
      goto op_column_out;
    }
  }else{
    t = pC->aType[p2];
  }

  /* Extract the content for the p2+1-th column.  Control can only
  ** reach this point if aOffset[p2], aOffset[p2+1], and pC->aType[p2] are
  ** all valid.
  */
  assert( p2<pC->nHdrParsed );
  assert( rc==SQLITE_OK );
  assert( sqlite3VdbeCheckMemInvariants(pDest) );
  if( VdbeMemDynamic(pDest) ) sqlite3VdbeMemSetNull(pDest);
  assert( t==pC->aType[p2] );
  if( pC->szRow>=aOffset[p2+1] ){
    /* This is the common case where the desired content fits on the original
    ** page - where the content is not on an overflow page */
    sqlite3VdbeSerialGet(pC->aRow+aOffset[p2], t, pDest);
  }else{
    /* This branch happens only when content is on overflow pages */
    if( ((pOp->p5 & (OPFLAG_LENGTHARG|OPFLAG_TYPEOFARG))!=0

  Mem *pData0;           /* First field to be combined into the record */
  Mem *pLast;            /* Last field of the record */
  int nField;            /* Number of fields in the record */
  char *zAffinity;       /* The affinity string for the record */
  int file_format;       /* File format to use for encoding */
  int i;                 /* Space used in zNewRecord[] header */
  int j;                 /* Space used in zNewRecord[] content */
  u32 len;               /* Length of a field */

  /* Assuming the record contains N fields, the record format looks
  ** like this:
  **
  ** ------------------------------------------------------------------------
  ** | hdr-size | type 0 | type 1 | ... | type N-1 | data0 | ... | data N-1 | 
  ** ------------------------------------------------------------------------

  /* Loop through the elements that will make up the record to figure
  ** out how much space is required for the new record.
  */
  pRec = pLast;
  do{
    assert( memIsValid(pRec) );
    pRec->uTemp = serial_type = sqlite3VdbeSerialType(pRec, file_format, &len);

    if( pRec->flags & MEM_Zero ){
      if( nData ){
        if( sqlite3VdbeMemExpandBlob(pRec) ) goto no_mem;
      }else{
        nZero += pRec->u.nZero;
        len -= pRec->u.nZero;
      }

** opened by cursor P1 in register P2
*/
#ifndef SQLITE_OMIT_BTREECOUNT
case OP_Count: {         /* out2 */
  i64 nEntry;
  BtCursor *pCrsr;

  assert( p->apCsr[pOp->p1]->eCurType==CURTYPE_BTREE );
  pCrsr = p->apCsr[pOp->p1]->uc.pCursor;
  assert( pCrsr );
  nEntry = 0;  /* Not needed.  Only used to silence a warning. */
  rc = sqlite3BtreeCount(pCrsr, &nEntry);
  pOut = out2Prerelease(p, pOp);
  pOut->u.i = nEntry;
  break;
}

    goto open_cursor_set_hints;
  }
  /* If the cursor is not currently open or is open on a different
  ** index, then fall through into OP_OpenRead to force a reopen */
case OP_OpenRead:
case OP_OpenWrite:


  assert( pOp->opcode==OP_OpenWrite || pOp->p5==0 || pOp->p5==OPFLAG_SEEKEQ );
  assert( p->bIsReader );
  assert( pOp->opcode==OP_OpenRead || pOp->opcode==OP_ReopenIdx
          || p->readOnly==0 );

  if( p->expired ){
    rc = SQLITE_ABORT_ROLLBACK;
    break;
  }

  nField = 0;
  pKeyInfo = 0;
  p2 = pOp->p2;
  iDb = pOp->p3;
  assert( iDb>=0 && iDb<db->nDb );
  assert( DbMaskTest(p->btreeMask, iDb) );
  pDb = &db->aDb[iDb];
  pX = pDb->pBt;
  assert( pX!=0 );
  if( pOp->opcode==OP_OpenWrite ){
    assert( OPFLAG_FORDELETE==BTREE_FORDELETE );
    wrFlag = BTREE_WRCSR | (pOp->p5 & OPFLAG_FORDELETE);
    assert( sqlite3SchemaMutexHeld(db, iDb, 0) );
    if( pDb->pSchema->file_format < p->minWriteFileFormat ){
      p->minWriteFileFormat = pDb->pSchema->file_format;
    }
  }else{
    wrFlag = 0;
  }

    nField = pKeyInfo->nField+pKeyInfo->nXField;
  }else if( pOp->p4type==P4_INT32 ){
    nField = pOp->p4.i;
  }
  assert( pOp->p1>=0 );
  assert( nField>=0 );
  testcase( nField==0 );  /* Table with INTEGER PRIMARY KEY and nothing else */
  pCur = allocateCursor(p, pOp->p1, nField, iDb, CURTYPE_BTREE);
  if( pCur==0 ) goto no_mem;
  pCur->nullRow = 1;
  pCur->isOrdered = 1;
  pCur->pgnoRoot = p2;
  rc = sqlite3BtreeCursor(pX, p2, wrFlag, pKeyInfo, pCur->uc.pCursor);
  pCur->pKeyInfo = pKeyInfo;
  /* Set the VdbeCursor.isTable variable. Previous versions of
  ** SQLite used to check if the root-page flags were sane at this point
  ** and report database corruption if they were not, but this check has
  ** since moved into the btree layer.  */  
  pCur->isTable = pOp->p4type!=P4_KEYINFO;

open_cursor_set_hints:
  assert( OPFLAG_BULKCSR==BTREE_BULKLOAD );
  assert( OPFLAG_SEEKEQ==BTREE_SEEK_EQ );
  testcase( pOp->p5 & OPFLAG_BULKCSR );
#ifdef SQLITE_ENABLE_CURSOR_HINT
  testcase( pOp->p2 & OPFLAG_SEEKEQ );
#endif
  sqlite3BtreeCursorHintFlags(pCur->uc.pCursor,
                               (pOp->p5 & (OPFLAG_BULKCSR|OPFLAG_SEEKEQ)));
  break;
}

/* Opcode: OpenEphemeral P1 P2 * P4 P5
** Synopsis: nColumn=P2
**
** Open a new cursor P1 to a transient table.

      SQLITE_OPEN_READWRITE |
      SQLITE_OPEN_CREATE |
      SQLITE_OPEN_EXCLUSIVE |
      SQLITE_OPEN_DELETEONCLOSE |
      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->pBt, 
                        BTREE_OMIT_JOURNAL | BTREE_SINGLE | pOp->p5, vfsFlags);
  if( rc==SQLITE_OK ){
    rc = sqlite3BtreeBeginTrans(pCx->pBt, 1);

      assert( pOp->p4type==P4_KEYINFO );
      rc = sqlite3BtreeCreateTable(pCx->pBt, &pgno, BTREE_BLOBKEY | pOp->p5); 
      if( rc==SQLITE_OK ){
        assert( pgno==MASTER_ROOT+1 );
        assert( pKeyInfo->db==db );
        assert( pKeyInfo->enc==ENC(db) );
        pCx->pKeyInfo = pKeyInfo;
        rc = sqlite3BtreeCursor(pCx->pBt, pgno, BTREE_WRCSR,
                                pKeyInfo, pCx->uc.pCursor);
      }
      pCx->isTable = 0;
    }else{
      rc = sqlite3BtreeCursor(pCx->pBt, MASTER_ROOT, BTREE_WRCSR,
                              0, pCx->uc.pCursor);
      pCx->isTable = 1;
    }
  }
  pCx->isOrdered = (pOp->p5!=BTREE_UNORDERED);
  break;
}

** key is sufficient to produce the required results.
*/
case OP_SorterOpen: {
  VdbeCursor *pCx;

  assert( pOp->p1>=0 );
  assert( pOp->p2>=0 );
  pCx = allocateCursor(p, pOp->p1, pOp->p2, -1, CURTYPE_SORTER);
  if( pCx==0 ) goto no_mem;
  pCx->pKeyInfo = pOp->p4.pKeyInfo;
  assert( pCx->pKeyInfo->db==db );
  assert( pCx->pKeyInfo->enc==ENC(db) );
  rc = sqlite3VdbeSorterInit(db, pOp->p3, pCx);
  break;
}

/* Opcode: SequenceTest P1 P2 * * *
** Synopsis: if( cursor[P1].ctr++ ) pc = P2
**
** P1 is a sorter cursor. If the sequence counter is currently zero, jump
** to P2. Regardless of whether or not the jump is taken, increment the
** the sequence value.
*/
case OP_SequenceTest: {
  VdbeCursor *pC;
  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
  pC = p->apCsr[pOp->p1];
  assert( isSorter(pC) );
  if( (pC->seqCount++)==0 ){
    goto jump_to_p2;
  }
  break;
}

/* Opcode: OpenPseudo P1 P2 P3 * *

** the pseudo-table.
*/
case OP_OpenPseudo: {
  VdbeCursor *pCx;

  assert( pOp->p1>=0 );
  assert( pOp->p3>=0 );
  pCx = allocateCursor(p, pOp->p1, pOp->p3, -1, CURTYPE_PSEUDO);
  if( pCx==0 ) goto no_mem;
  pCx->nullRow = 1;
  pCx->uc.pseudoTableReg = pOp->p2;
  pCx->isTable = 1;
  assert( pOp->p5==0 );
  break;
}

/* Opcode: Close P1 * * * *
**

** first 63 columns of the table or index that are actually used
** by the cursor.  The high-order bit is set if any column after
** the 64th is used.
*/
case OP_ColumnsUsed: {
  VdbeCursor *pC;
  pC = p->apCsr[pOp->p1];
  assert( pC->eCurType==CURTYPE_BTREE );
  pC->maskUsed = *(u64*)pOp->p4.pI64;
  break;
}
#endif

/* Opcode: SeekGE P1 P2 P3 P4 *
** Synopsis: key=r[P3@P4]
**
** If cursor P1 refers to an SQL table (B-Tree that uses integer keys), 
** use the value in register P3 as the key.  If cursor P1 refers 
** to an SQL index, then P3 is the first in an array of P4 registers 
** that are used as an unpacked index key. 
**
** Reposition cursor P1 so that  it points to the smallest entry that 
** is greater than or equal to the key value. If there are no records 
** greater than or equal to the key and P2 is not zero, then jump to P2.
**
** If the cursor P1 was opened using the OPFLAG_SEEKEQ flag, then this
** opcode will always land on a record that equally equals the key, or
** else jump immediately to P2.  When the cursor is OPFLAG_SEEKEQ, this
** opcode must be followed by an IdxLE opcode with the same arguments.
** The IdxLE opcode will be skipped if this opcode succeeds, but the
** IdxLE opcode will be used on subsequent loop iterations.
**
** This opcode leaves the cursor configured to move in forward order,
** from the beginning toward the end.  In other words, the cursor is
** configured to use Next, not Prev.
**
** See also: Found, NotFound, SeekLt, SeekGt, SeekLe
*/

** is less than or equal to the key value. If there are no records 
** less than or equal to the key and P2 is not zero, then jump to P2.
**
** 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 the cursor P1 was opened using the OPFLAG_SEEKEQ flag, then this
** opcode will always land on a record that equally equals the key, or
** else jump immediately to P2.  When the cursor is OPFLAG_SEEKEQ, this
** opcode must be followed by an IdxGE opcode with the same arguments.
** The IdxGE opcode will be skipped if this opcode succeeds, but the
** IdxGE opcode will be used on subsequent loop iterations.
**
** See also: Found, NotFound, SeekGt, SeekGe, SeekLt
*/
case OP_SeekLT:         /* jump, in3 */
case OP_SeekLE:         /* jump, in3 */
case OP_SeekGE:         /* jump, in3 */
case OP_SeekGT: {       /* jump, in3 */
  int res;           /* Comparison result */
  int oc;            /* Opcode */
  VdbeCursor *pC;    /* The cursor to seek */
  UnpackedRecord r;  /* The key to seek for */
  int nField;        /* Number of columns or fields in the key */
  i64 iKey;          /* The rowid we are to seek to */
  int eqOnly;        /* Only interested in == results */

  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
  assert( pOp->p2!=0 );
  pC = p->apCsr[pOp->p1];
  assert( pC!=0 );
  assert( pC->eCurType==CURTYPE_BTREE );
  assert( OP_SeekLE == OP_SeekLT+1 );
  assert( OP_SeekGE == OP_SeekLT+2 );
  assert( OP_SeekGT == OP_SeekLT+3 );
  assert( pC->isOrdered );
  assert( pC->uc.pCursor!=0 );
  oc = pOp->opcode;
  eqOnly = 0;
  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 );










    /* 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);
    }

      else if( pIn3->u.r>(double)iKey ){
        assert( OP_SeekLE==(OP_SeekLT+1) );
        assert( OP_SeekGT==(OP_SeekGE+1) );
        assert( (OP_SeekLT & 0x0001)==(OP_SeekGE & 0x0001) );
        if( (oc & 0x0001)==(OP_SeekLT & 0x0001) ) oc++;
      }
    } 
    rc = sqlite3BtreeMovetoUnpacked(pC->uc.pCursor, 0, (u64)iKey, 0, &res);
    pC->movetoTarget = iKey;  /* Used by OP_Delete */
    if( rc!=SQLITE_OK ){
      goto abort_due_to_error;
    }
  }else{
    /* For a cursor with the BTREE_SEEK_EQ hint, only the OP_SeekGE and
    ** OP_SeekLE opcodes are allowed, and these must be immediately followed
    ** by an OP_IdxGT or OP_IdxLT opcode, respectively, with the same key.
    */
    if( sqlite3BtreeCursorHasHint(pC->uc.pCursor, BTREE_SEEK_EQ) ){
      eqOnly = 1;
      assert( pOp->opcode==OP_SeekGE || pOp->opcode==OP_SeekLE );
      assert( pOp[1].opcode==OP_IdxLT || pOp[1].opcode==OP_IdxGT );
      assert( pOp[1].p1==pOp[0].p1 );
      assert( pOp[1].p2==pOp[0].p2 );
      assert( pOp[1].p3==pOp[0].p3 );
      assert( pOp[1].p4.i==pOp[0].p4.i );
    }

    nField = pOp->p4.i;
    assert( pOp->p4type==P4_INT32 );
    assert( nField>0 );
    r.pKeyInfo = pC->pKeyInfo;
    r.nField = (u16)nField;

    /* The next line of code computes as follows, only faster:

    assert( oc!=OP_SeekLT || r.default_rc==+1 );

    r.aMem = &aMem[pOp->p3];
#ifdef SQLITE_DEBUG
    { int i; for(i=0; i<r.nField; i++) assert( memIsValid(&r.aMem[i]) ); }
#endif
    ExpandBlob(r.aMem);
    r.eqSeen = 0;
    rc = sqlite3BtreeMovetoUnpacked(pC->uc.pCursor, &r, 0, 0, &res);
    if( rc!=SQLITE_OK ){
      goto abort_due_to_error;
    }
    if( eqOnly && r.eqSeen==0 ){
      assert( res!=0 );
      goto seek_not_found;
    }
  }
  pC->deferredMoveto = 0;
  pC->cacheStatus = CACHE_STALE;
#ifdef SQLITE_TEST
  sqlite3_search_count++;
#endif
  if( oc>=OP_SeekGE ){  assert( oc==OP_SeekGE || oc==OP_SeekGT );
    if( res<0 || (res==0 && oc==OP_SeekGT) ){
      res = 0;
      rc = sqlite3BtreeNext(pC->uc.pCursor, &res);
      if( rc!=SQLITE_OK ) goto abort_due_to_error;
    }else{
      res = 0;
    }
  }else{
    assert( oc==OP_SeekLT || oc==OP_SeekLE );
    if( res>0 || (res==0 && oc==OP_SeekLT) ){
      res = 0;
      rc = sqlite3BtreePrevious(pC->uc.pCursor, &res);
      if( rc!=SQLITE_OK ) goto abort_due_to_error;
    }else{
      /* res might be negative because the table is empty.  Check to
      ** see if this is the case.
      */
      res = sqlite3BtreeEof(pC->uc.pCursor);
    }
  }
seek_not_found:
  assert( pOp->p2>0 );
  VdbeBranchTaken(res!=0,2);
  if( res ){
    goto jump_to_p2;
  }else if( eqOnly ){
    assert( pOp[1].opcode==OP_IdxLT || pOp[1].opcode==OP_IdxGT );
    pOp++; /* Skip the OP_IdxLt or OP_IdxGT that follows */
  }
  break;
}

/* Opcode: Seek P1 P2 * * *
** Synopsis:  intkey=r[P2]
**
** P1 is an open table cursor and P2 is a rowid integer.  Arrange
** for P1 to move so that it points to the rowid given by P2.
**
** This is actually a deferred seek.  Nothing actually happens until
** the cursor is used to read a record.  That way, if no reads
** occur, no unnecessary I/O happens.
*/
case OP_Seek: {    /* in2 */
  VdbeCursor *pC;

  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
  pC = p->apCsr[pOp->p1];
  assert( pC!=0 );
  assert( pC->eCurType==CURTYPE_BTREE );
  assert( pC->uc.pCursor!=0 );
  assert( pC->isTable );
  pC->nullRow = 0;
  pIn2 = &aMem[pOp->p2];
  pC->movetoTarget = sqlite3VdbeIntValue(pIn2);
  pC->deferredMoveto = 1;
  break;
}

  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 );
  pFree = 0;
  if( pOp->p4.i>0 ){
    r.pKeyInfo = pC->pKeyInfo;
    r.nField = (u16)pOp->p4.i;
    r.aMem = pIn3;
    for(ii=0; ii<r.nField; ii++){

    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);
  sqlite3DbFree(db, pFree);
  if( rc!=SQLITE_OK ){
    break;
  }
  pC->seekResult = res;
  alreadyExists = (res==0);
  pC->nullRow = 1-alreadyExists;

  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
  pC = p->apCsr[pOp->p1];
  assert( pC!=0 );
#ifdef SQLITE_DEBUG
  pC->seekOp = 0;
#endif
  assert( pC->isTable );
  assert( pC->eCurType==CURTYPE_BTREE );
  pCrsr = pC->uc.pCursor;
  assert( pCrsr!=0 );
  res = 0;
  iKey = pIn3->u.i;
  rc = sqlite3BtreeMovetoUnpacked(pCrsr, 0, iKey, 0, &res);
  assert( rc==SQLITE_OK || res==0 );
  pC->movetoTarget = iKey;  /* Used by OP_Delete */
  pC->nullRow = 0;

** Write the sequence number into register P2.
** The sequence number on the cursor is incremented after this
** instruction.  
*/
case OP_Sequence: {           /* out2 */
  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
  assert( p->apCsr[pOp->p1]!=0 );
  assert( p->apCsr[pOp->p1]->eCurType!=CURTYPE_VTAB );
  pOut = out2Prerelease(p, pOp);
  pOut->u.i = p->apCsr[pOp->p1]->seqCount++;
  break;
}


/* Opcode: NewRowid P1 P2 P3 * *

  v = 0;
  res = 0;
  pOut = out2Prerelease(p, pOp);
  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
  pC = p->apCsr[pOp->p1];
  assert( pC!=0 );
  assert( pC->eCurType==CURTYPE_BTREE );
  assert( pC->uc.pCursor!=0 );
  {
    /* The next rowid or record number (different terms for the same
    ** thing) is obtained in a two-step algorithm.
    **
    ** First we attempt to find the largest existing rowid and add one
    ** to that.  But if the largest existing rowid is already the maximum
    ** positive integer, we have to fall through to the second

    ** Others complain about 0x7ffffffffffffffffLL.  The following macro seems
    ** to provide the constant while making all compilers happy.
    */
#   define MAX_ROWID  (i64)( (((u64)0x7fffffff)<<32) | (u64)0xffffffff )
#endif

    if( !pC->useRandomRowid ){
      rc = sqlite3BtreeLast(pC->uc.pCursor, &res);
      if( rc!=SQLITE_OK ){
        goto abort_due_to_error;
      }
      if( res ){
        v = 1;   /* IMP: R-61914-48074 */
      }else{
        assert( sqlite3BtreeCursorIsValid(pC->uc.pCursor) );
        rc = sqlite3BtreeKeySize(pC->uc.pCursor, &v);
        assert( rc==SQLITE_OK );   /* Cannot fail following BtreeLast() */
        if( v>=MAX_ROWID ){
          pC->useRandomRowid = 1;
        }else{
          v++;   /* IMP: R-29538-34987 */
        }
      }

      ** it finds one that is not previously used. */
      assert( pOp->p3==0 );  /* We cannot be in random rowid mode if this is
                             ** an AUTOINCREMENT table. */
      cnt = 0;
      do{
        sqlite3_randomness(sizeof(v), &v);
        v &= (MAX_ROWID>>1); v++;  /* Ensure that v is greater than zero */
      }while(  ((rc = sqlite3BtreeMovetoUnpacked(pC->uc.pCursor, 0, (u64)v,
                                                 0, &res))==SQLITE_OK)
            && (res==0)
            && (++cnt<100));
      if( rc==SQLITE_OK && res==0 ){
        rc = SQLITE_FULL;   /* IMP: R-38219-53002 */
        goto abort_due_to_error;
      }

  int op;           /* Opcode for update hook: SQLITE_UPDATE or SQLITE_INSERT */

  pData = &aMem[pOp->p2];
  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
  assert( memIsValid(pData) );
  pC = p->apCsr[pOp->p1];
  assert( pC!=0 );
  assert( pC->eCurType==CURTYPE_BTREE );
  assert( pC->uc.pCursor!=0 );
  assert( pC->isTable );
  REGISTER_TRACE(pOp->p2, pData);

  if( pOp->opcode==OP_Insert ){
    pKey = &aMem[pOp->p3];
    assert( pKey->flags & MEM_Int );
    assert( memIsValid(pKey) );

  }
  seekResult = ((pOp->p5 & OPFLAG_USESEEKRESULT) ? pC->seekResult : 0);
  if( pData->flags & MEM_Zero ){
    nZero = pData->u.nZero;
  }else{
    nZero = 0;
  }
  rc = sqlite3BtreeInsert(pC->uc.pCursor, 0, iKey,
                          pData->z, pData->n, nZero,
                          (pOp->p5 & OPFLAG_APPEND)!=0, seekResult
  );
  pC->deferredMoveto = 0;
  pC->cacheStatus = CACHE_STALE;

  /* Invoke the update-hook if required. */

case OP_Delete: {
  VdbeCursor *pC;
  u8 hasUpdateCallback;

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

  hasUpdateCallback = db->xUpdateCallback && pOp->p4.z && pC->isTable;
  if( pOp->p5 && hasUpdateCallback ){
    sqlite3BtreeKeySize(pC->uc.pCursor, &pC->movetoTarget);
  }

#ifdef SQLITE_DEBUG
  /* The seek operation that positioned the cursor prior to OP_Delete will
  ** have also set the pC->movetoTarget field to the rowid of the row that
  ** is being deleted */
  if( pOp->p4.z && pC->isTable && pOp->p5==0 ){
    i64 iKey = 0;
    sqlite3BtreeKeySize(pC->uc.pCursor, &iKey);
    assert( pC->movetoTarget==iKey ); 
  }
#endif
 
  rc = sqlite3BtreeDelete(pC->uc.pCursor, pOp->p5);
  pC->cacheStatus = CACHE_STALE;

  /* Invoke the update-hook if required. */
  if( rc==SQLITE_OK && hasUpdateCallback ){
    db->xUpdateCallback(db->pUpdateArg, SQLITE_DELETE,
                        db->aDb[pC->iDb].zName, pOp->p4.z, pC->movetoTarget);
    assert( pC->iDb>=0 );

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

  /* Note that RowKey and RowData are really exactly the same instruction */
  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->isTable || pOp->opcode!=OP_RowData );
  assert( pC->isTable==0 || pOp->opcode==OP_RowData );

  assert( pC->nullRow==0 );

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

  /* The OP_RowKey and OP_RowData opcodes always follow OP_NotExists 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().