Wapp

#ifndef USE_SYSTEM_SQLITE
/******************************************************************************
** This file is an amalgamation of many separate C source files from SQLite
** version 3.45.0.  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
** programs, you need this file and the "sqlite3.h" header file that defines
** the programming interface to the SQLite library.  (If you do not have
** the "sqlite3.h" header file at hand, you will find a copy embedded within
** the text of this file.  Search for "Begin file sqlite3.h" to find the start
** of the embedded sqlite3.h header file.) Additional code files may be needed
** if you want a wrapper to interface SQLite with your choice of programming
** language. The code for the "sqlite3" command-line shell is also in a
** separate file. This file contains only code for the core SQLite library.
**
** The content in this amalgamation comes from Fossil check-in
** f47a5f4e0ce078e6cc1183e6cbb3c4013af3.
*/
#define SQLITE_CORE 1
#define SQLITE_AMALGAMATION 1
#ifndef SQLITE_PRIVATE
# define SQLITE_PRIVATE static
#endif
/************** Begin file sqliteInt.h ***************************************/

** been edited in any way since it was last checked in, then the last
** four hexadecimal digits of the hash may be modified.
**
** See also: [sqlite3_libversion()],
** [sqlite3_libversion_number()], [sqlite3_sourceid()],
** [sqlite_version()] and [sqlite_source_id()].
*/
#define SQLITE_VERSION        "3.45.0"
#define SQLITE_VERSION_NUMBER 3045000
#define SQLITE_SOURCE_ID      "2024-01-12 11:44:49 f47a5f4e0ce078e6cc1183e6cbb3c4013af379b496efae94863a42e5c39928ed"

/*
** 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

** to an ORDER BY clause, all fields required by the caller are present in the
** sorted records. However, if SQLite determines based on the declared type
** of a table column that its values are likely to be very large - larger
** than the configured sorter-reference size threshold - then a reference
** is stored in each sorted record and the required column values loaded
** from the database as records are returned in sorted order. The default
** value for this option is to never use this optimization. Specifying a
** negative value for this option restores the default behavior.
** This option is only available if SQLite is compiled with the
** [SQLITE_ENABLE_SORTER_REFERENCES] compile-time option.
**
** [[SQLITE_CONFIG_MEMDB_MAXSIZE]]
** <dt>SQLITE_CONFIG_MEMDB_MAXSIZE
** <dd>The SQLITE_CONFIG_MEMDB_MAXSIZE option accepts a single parameter
** [sqlite3_int64] parameter which is the default maximum size for an in-memory

**
** [[SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE]]
** <dt>SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE</dt>
** <dd> Usually, when a database in wal mode is closed or detached from a
** database handle, SQLite checks if this will mean that there are now no
** connections at all to the database. If so, it performs a checkpoint
** operation before closing the connection. This option may be used to
** override this behavior. The first parameter passed to this operation
** is an integer - positive to disable checkpoints-on-close, or zero (the
** default) to enable them, and negative to leave the setting unchanged.
** The second parameter is a pointer to an integer
** into which is written 0 or 1 to indicate whether checkpoints-on-close
** have been disabled - 0 if they are not disabled, 1 if they are.
** </dd>
**

** <li> sqlite3_extended_errcode()
** <li> sqlite3_errmsg()
** <li> sqlite3_errmsg16()
** <li> sqlite3_error_offset()
** </ul>
**
** ^The sqlite3_errmsg() and sqlite3_errmsg16() return English-language
** text that describes the error, as either UTF-8 or UTF-16 respectively,
** or NULL if no error message is available.
** (See how SQLite handles [invalid UTF] for exceptions to this rule.)
** ^(Memory to hold the error message string is managed internally.
** The application does not need to worry about freeing the result.
** However, the error string might be overwritten or deallocated by
** subsequent calls to other SQLite interface functions.)^
**
** ^The sqlite3_errstr(E) interface returns the English-language text
** that describes the [result code] E, as UTF-8, or NULL if E is not an
** result code for which a text error message is available.
** ^(Memory to hold the error message string is managed internally
** and must not be freed by the application)^.
**
** ^If the most recent error references a specific token in the input
** SQL, the sqlite3_error_offset() interface returns the byte offset
** of the start of that token.  ^The byte offset returned by
** sqlite3_error_offset() assumes that the input SQL is UTF8.

** are innocuous.  Developers are advised to avoid using the
** SQLITE_INNOCUOUS flag for application-defined functions unless the
** function has been carefully audited and found to be free of potentially
** security-adverse side-effects and information-leaks.
** </dd>
**
** [[SQLITE_SUBTYPE]] <dt>SQLITE_SUBTYPE</dt><dd>
** The SQLITE_SUBTYPE flag indicates to SQLite that a function might call
** [sqlite3_value_subtype()] to inspect the sub-types of its arguments.
** This flag instructs SQLite to omit some corner-case optimizations that
** might disrupt the operation of the [sqlite3_value_subtype()] function,
** causing it to return zero rather than the correct subtype().
** SQL functions that invokes [sqlite3_value_subtype()] should have this
** property.  If the SQLITE_SUBTYPE property is omitted, then the return
** value from [sqlite3_value_subtype()] might sometimes be zero even though
** a non-zero subtype was specified by the function argument expression.
**
** [[SQLITE_RESULT_SUBTYPE]] <dt>SQLITE_RESULT_SUBTYPE</dt><dd>
** The SQLITE_RESULT_SUBTYPE flag indicates to SQLite that a function might call
** [sqlite3_result_subtype()] to cause a sub-type to be associated with its
** result.
** Every function that invokes [sqlite3_result_subtype()] should have this
** property.  If it does not, then the call to [sqlite3_result_subtype()]
** might become a no-op if the function is used as term in an
** [expression index].  On the other hand, SQL functions that never invoke
** [sqlite3_result_subtype()] should avoid setting this property, as the
** purpose of this property is to disable certain optimizations that are
** incompatible with subtypes.
** </dd>
** </dl>
*/
#define SQLITE_DETERMINISTIC    0x000000800
#define SQLITE_DIRECTONLY       0x000080000
#define SQLITE_SUBTYPE          0x000100000
#define SQLITE_INNOCUOUS        0x000200000
#define SQLITE_RESULT_SUBTYPE   0x001000000

/*
** CAPI3REF: Deprecated Functions
** DEPRECATED
**
** These functions are [deprecated].  In order to maintain
** backwards compatibility with older code, these functions continue

** METHOD: sqlite3_value
**
** The sqlite3_value_subtype(V) function returns the subtype for
** an [application-defined SQL function] argument V.  The subtype
** information can be used to pass a limited amount of context from
** one SQL function to another.  Use the [sqlite3_result_subtype()]
** routine to set the subtype for the return value of an SQL function.
**
** Every [application-defined SQL function] that invoke this interface
** should include the [SQLITE_SUBTYPE] property in the text
** encoding argument when the function is [sqlite3_create_function|registered].
** If the [SQLITE_SUBTYPE] property is omitted, then sqlite3_value_subtype()
** might return zero instead of the upstream subtype in some corner cases.
*/
SQLITE_API unsigned int sqlite3_value_subtype(sqlite3_value*);

/*
** CAPI3REF: Copy And Free SQL Values
** METHOD: sqlite3_value
**

** SQLite is free to discard the auxiliary data at any time, including: <ul>
** <li> ^(when the corresponding function parameter changes)^, or
** <li> ^(when [sqlite3_reset()] or [sqlite3_finalize()] is called for the
**      SQL statement)^, or
** <li> ^(when sqlite3_set_auxdata() is invoked again on the same
**       parameter)^, or
** <li> ^(during the original sqlite3_set_auxdata() call when a memory
**      allocation error occurs.)^
** <li> ^(during the original sqlite3_set_auxdata() call if the function
**      is evaluated during query planning instead of during query execution,
**      as sometimes happens with [SQLITE_ENABLE_STAT4].)^ </ul>
**
** Note the last two bullets in particular.  The destructor X in
** sqlite3_set_auxdata(C,N,P,X) might be called immediately, before the
** sqlite3_set_auxdata() interface even returns.  Hence sqlite3_set_auxdata()
** should be called near the end of the function implementation and the
** function implementation should not make any use of P after
** sqlite3_set_auxdata() has been called.  Furthermore, a call to
** sqlite3_get_auxdata() that occurs immediately after a corresponding call
** to sqlite3_set_auxdata() might still return NULL if an out-of-memory
** condition occurred during the sqlite3_set_auxdata() call or if the
** function is being evaluated during query planning rather than during
** query execution.
**
** ^(In practice, auxiliary data is preserved between function calls for
** function parameters that are compile-time constants, including literal
** values and [parameters] and expressions composed from the same.)^
**
** The value of the N parameter to these interfaces should be non-negative.
** Future enhancements may make use of negative N values to define new

** <li> An out-of-memory error occurs during the call to
**      sqlite3_set_clientdata() which attempts to register pointer P.
** <li> A subsequent call to sqlite3_set_clientdata(D,N,P,X) is made
**      with the same D and N parameters.
** <li> The database connection closes.  SQLite does not make any guarantees
**      about the order in which destructors are called, only that all
**      destructors will be called exactly once at some point during the
**      database connection closing process.
** </ul>
**
** SQLite does not do anything with client data other than invoke
** destructors on the client data at the appropriate time.  The intended
** use for client data is to provide a mechanism for wrapper libraries
** to store additional information about an SQLite database connection.
**

** The sqlite3_result_subtype(C,T) function causes the subtype of
** the result from the [application-defined SQL function] with
** [sqlite3_context] C to be the value T.  Only the lower 8 bits
** of the subtype T are preserved in current versions of SQLite;
** higher order bits are discarded.
** The number of subtype bytes preserved by SQLite might increase
** in future releases of SQLite.
**
** Every [application-defined SQL function] that invokes this interface
** should include the [SQLITE_RESULT_SUBTYPE] property in its
** text encoding argument when the SQL function is
** [sqlite3_create_function|registered].  If the [SQLITE_RESULT_SUBTYPE]
** property is omitted from the function that invokes sqlite3_result_subtype(),
** then in some cases the sqlite3_result_subtype() might fail to set
** the result subtype.
**
** If SQLite is compiled with -DSQLITE_STRICT_SUBTYPE=1, then any
** SQL function that invokes the sqlite3_result_subtype() interface
** and that does not have the SQLITE_RESULT_SUBTYPE property will raise
** an error.  Future versions of SQLite might enable -DSQLITE_STRICT_SUBTYPE=1
** by default.
*/
SQLITE_API void sqlite3_result_subtype(sqlite3_context*,unsigned int);

/*
** CAPI3REF: Define New Collating Sequences
** METHOD: sqlite3
**

** </ol>
** ^If the S argument to sqlite3_txn_state(D,S) is not the name of
** a valid schema, then -1 is returned.
*/
SQLITE_API int sqlite3_txn_state(sqlite3*,const char *zSchema);

/*
** CAPI3REF: Allowed return values from sqlite3_txn_state()
** KEYWORDS: {transaction state}
**
** These constants define the current transaction state of a database file.
** ^The [sqlite3_txn_state(D,S)] interface returns one of these
** constants in order to describe the transaction state of schema S
** in [database connection] D.
**

** invoked whenever the database connection closes or when the callback
** is overwritten by another invocation of sqlite3_autovacuum_pages().
**
** <p>^There is only one autovacuum pages callback per database connection.
** ^Each call to the sqlite3_autovacuum_pages() interface overrides all
** previous invocations for that database connection.  ^If the callback
** argument (C) to sqlite3_autovacuum_pages(D,C,P,X) is a NULL pointer,
** then the autovacuum steps callback is canceled.  The return value
** from sqlite3_autovacuum_pages() is normally SQLITE_OK, but might
** be some other error code if something goes wrong.  The current
** implementation will only return SQLITE_OK or SQLITE_MISUSE, but other
** return codes might be added in future releases.
**
** <p>If no autovacuum pages callback is specified (the usual case) or
** a NULL pointer is provided for the callback,

  int (*xRelease)(sqlite3_vtab *pVTab, int);
  int (*xRollbackTo)(sqlite3_vtab *pVTab, int);
  /* The methods above are in versions 1 and 2 of the sqlite_module object.
  ** Those below are for version 3 and greater. */
  int (*xShadowName)(const char*);
  /* The methods above are in versions 1 through 3 of the sqlite_module object.
  ** Those below are for version 4 and greater. */
  int (*xIntegrity)(sqlite3_vtab *pVTab, const char *zSchema,
                    const char *zTabName, int mFlags, char **pzErr);
};

/*
** CAPI3REF: Virtual Table Indexing Information
** KEYWORDS: sqlite3_index_info
**
** The sqlite3_index_info structure and its substructures is used as part

** ^If the blob handle being closed was opened for read-write access, and if
** the database is in auto-commit mode and there are no other open read-write
** blob handles or active write statements, the current transaction is
** committed. ^If an error occurs while committing the transaction, an error
** code is returned and the transaction rolled back.
**
** Calling this function with an argument that is not a NULL pointer or an
** open blob handle results in undefined behavior. ^Calling this routine
** with a null pointer (such as would be returned by a failed call to
** [sqlite3_blob_open()]) is a harmless no-op. ^Otherwise, if this function
** is passed a valid open blob handle, the values returned by the
** sqlite3_errcode() and sqlite3_errmsg() functions are set before returning.
*/
SQLITE_API int sqlite3_blob_close(sqlite3_blob *);

** In such cases, the
** mutex must be exited an equal number of times before another thread
** can enter.)^  If the same thread tries to enter any mutex other
** than an SQLITE_MUTEX_RECURSIVE more than once, the behavior is undefined.
**
** ^(Some systems (for example, Windows 95) do not support the operation
** implemented by sqlite3_mutex_try().  On those systems, sqlite3_mutex_try()
** will always return SQLITE_BUSY. In most cases the SQLite core only uses
** sqlite3_mutex_try() as an optimization, so this is acceptable
** behavior. The exceptions are unix builds that set the
** SQLITE_ENABLE_SETLK_TIMEOUT build option. In that case a working
** sqlite3_mutex_try() is required.)^
**
** ^The sqlite3_mutex_leave() routine exits a mutex that was
** previously entered by the same thread.   The behavior
** is undefined if the mutex is not currently entered by the
** calling thread or is not currently allocated.
**
** ^If the argument to sqlite3_mutex_enter(), sqlite3_mutex_try(),

#define SQLITE_TESTCTRL_BITVEC_TEST              8
#define SQLITE_TESTCTRL_FAULT_INSTALL            9
#define SQLITE_TESTCTRL_BENIGN_MALLOC_HOOKS     10
#define SQLITE_TESTCTRL_PENDING_BYTE            11
#define SQLITE_TESTCTRL_ASSERT                  12
#define SQLITE_TESTCTRL_ALWAYS                  13
#define SQLITE_TESTCTRL_RESERVE                 14  /* NOT USED */
#define SQLITE_TESTCTRL_JSON_SELFCHECK          14
#define SQLITE_TESTCTRL_OPTIMIZATIONS           15
#define SQLITE_TESTCTRL_ISKEYWORD               16  /* NOT USED */
#define SQLITE_TESTCTRL_SCRATCHMALLOC           17  /* NOT USED */
#define SQLITE_TESTCTRL_INTERNAL_FUNCTIONS      17
#define SQLITE_TESTCTRL_LOCALTIME_FAULT         18
#define SQLITE_TESTCTRL_EXPLAIN_STMT            19  /* NOT USED */
#define SQLITE_TESTCTRL_ONCE_RESET_THRESHOLD    19

** the other connections to use as the blocking connection.
**
** ^(There may be at most one unlock-notify callback registered by a
** blocked connection. If sqlite3_unlock_notify() is called when the
** blocked connection already has a registered unlock-notify callback,
** then the new callback replaces the old.)^ ^If sqlite3_unlock_notify() is
** called with a NULL pointer as its second argument, then any existing
** unlock-notify callback is canceled. ^The blocked connections
** unlock-notify callback may also be canceled by closing the blocked
** connection using [sqlite3_close()].
**
** The unlock-notify callback is not reentrant. If an application invokes
** any sqlite3_xxx API functions from within an unlock-notify callback, a
** crash or deadlock may be the result.
**
** ^Unless deadlock is detected (see below), sqlite3_unlock_notify() always

**   an OOM condition or IO error), an appropriate SQLite error code is
**   returned.
**
**   This function may be quite inefficient if used with an FTS5 table
**   created with the "columnsize=0" option.
**
** xColumnText:
**   If parameter iCol is less than zero, or greater than or equal to the
**   number of columns in the table, SQLITE_RANGE is returned.
**
**   Otherwise, this function attempts to retrieve the text of column iCol of
**   the current document. If successful, (*pz) is set to point to a buffer
**   containing the text in utf-8 encoding, (*pn) is set to the size in bytes
**   (not characters) of the buffer and SQLITE_OK is returned. Otherwise,
**   if an error occurs, an SQLite error code is returned and the final values
**   of (*pz) and (*pn) are undefined.
**
** xPhraseCount:
**   Returns the number of phrases in the current query expression.
**
** xPhraseSize:
**   If parameter iCol is less than zero, or greater than or equal to the
**   number of phrases in the current query, as returned by xPhraseCount,
**   0 is returned. Otherwise, this function returns the number of tokens in
**   phrase iPhrase of the query. Phrases are numbered starting from zero.
**
** xInstCount:
**   Set *pnInst to the total number of occurrences of all phrases within
**   the query within the current row. Return SQLITE_OK if successful, or
**   an error code (i.e. SQLITE_NOMEM) if an error occurs.
**
**   This API can be quite slow if used with an FTS5 table created with the
**   "detail=none" or "detail=column" option. If the FTS5 table is created
**   with either "detail=none" or "detail=column" and "content=" option
**   (i.e. if it is a contentless table), then this API always returns 0.
**
** xInst:
**   Query for the details of phrase match iIdx within the current row.
**   Phrase matches are numbered starting from zero, so the iIdx argument
**   should be greater than or equal to zero and smaller than the value
**   output by xInstCount(). If iIdx is less than zero or greater than
**   or equal to the value returned by xInstCount(), SQLITE_RANGE is returned.
**
**   Otherwise, output parameter *piPhrase is set to the phrase number, *piCol
**   to the column in which it occurs and *piOff the token offset of the
**   first token of the phrase. SQLITE_OK is returned if successful, or an
**   error code (i.e. SQLITE_NOMEM) if an error occurs.
**
**   This API can be quite slow if used with an FTS5 table created with the
**   "detail=none" or "detail=column" option.
**
** xRowid:
**   Returns the rowid of the current row.
**

**   current query is executed. Any column filter that applies to
**   phrase iPhrase of the current query is included in $p. For each
**   row visited, the callback function passed as the fourth argument
**   is invoked. The context and API objects passed to the callback
**   function may be used to access the properties of each matched row.
**   Invoking Api.xUserData() returns a copy of the pointer passed as
**   the third argument to pUserData.
**
**   If parameter iPhrase is less than zero, or greater than or equal to
**   the number of phrases in the query, as returned by xPhraseCount(),
**   this function returns SQLITE_RANGE.
**
**   If the callback function returns any value other than SQLITE_OK, the
**   query is abandoned and the xQueryPhrase function returns immediately.
**   If the returned value is SQLITE_DONE, xQueryPhrase returns SQLITE_OK.
**   Otherwise, the error code is propagated upwards.
**
**   If the query runs to completion without incident, SQLITE_OK is returned.

**   xPhraseFirstColumn() may also be obtained using xPhraseFirst/xPhraseNext
**   (or xInst/xInstCount). The chief advantage of this API is that it is
**   significantly more efficient than those alternatives when used with
**   "detail=column" tables.
**
** xPhraseNextColumn()
**   See xPhraseFirstColumn above.
**
** xQueryToken(pFts5, iPhrase, iToken, ppToken, pnToken)
**   This is used to access token iToken of phrase iPhrase of the current
**   query. Before returning, output parameter *ppToken is set to point
**   to a buffer containing the requested token, and *pnToken to the
**   size of this buffer in bytes.
**
**   If iPhrase or iToken are less than zero, or if iPhrase is greater than
**   or equal to the number of phrases in the query as reported by
**   xPhraseCount(), or if iToken is equal to or greater than the number of
**   tokens in the phrase, SQLITE_RANGE is returned and *ppToken and *pnToken
     are both zeroed.
**
**   The output text is not a copy of the query text that specified the
**   token. It is the output of the tokenizer module. For tokendata=1
**   tables, this includes any embedded 0x00 and trailing data.
**
** xInstToken(pFts5, iIdx, iToken, ppToken, pnToken)
**   This is used to access token iToken of phrase hit iIdx within the
**   current row. If iIdx is less than zero or greater than or equal to the
**   value returned by xInstCount(), SQLITE_RANGE is returned.  Otherwise,
**   output variable (*ppToken) is set to point to a buffer containing the
**   matching document token, and (*pnToken) to the size of that buffer in
**   bytes. This API is not available if the specified token matches a
**   prefix query term. In that case both output variables are always set
**   to 0.
**
**   The output text is not a copy of the document text that was tokenized.
**   It is the output of the tokenizer module. For tokendata=1 tables, this
**   includes any embedded 0x00 and trailing data.
**
**   This API can be quite slow if used with an FTS5 table created with the
**   "detail=none" or "detail=column" option.
*/
struct Fts5ExtensionApi {
  int iVersion;                   /* Currently always set to 3 */

  void *(*xUserData)(Fts5Context*);

  int (*xColumnCount)(Fts5Context*);
  int (*xRowCount)(Fts5Context*, sqlite3_int64 *pnRow);
  int (*xColumnTotalSize)(Fts5Context*, int iCol, sqlite3_int64 *pnToken);

  void *(*xGetAuxdata)(Fts5Context*, int bClear);

  int (*xPhraseFirst)(Fts5Context*, int iPhrase, Fts5PhraseIter*, int*, int*);
  void (*xPhraseNext)(Fts5Context*, Fts5PhraseIter*, int *piCol, int *piOff);

  int (*xPhraseFirstColumn)(Fts5Context*, int iPhrase, Fts5PhraseIter*, int*);
  void (*xPhraseNextColumn)(Fts5Context*, Fts5PhraseIter*, int *piCol);

  /* Below this point are iVersion>=3 only */
  int (*xQueryToken)(Fts5Context*,
      int iPhrase, int iToken,
      const char **ppToken, int *pnToken
  );
  int (*xInstToken)(Fts5Context*, int iIdx, int iToken, const char**, int*);
};

/*
** CUSTOM AUXILIARY FUNCTIONS
*************************************************************************/

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

** Maximum number of pages in one database file.
**
** This is really just the default value for the max_page_count pragma.
** This value can be lowered (or raised) at run-time using that the
** max_page_count macro.
*/
#ifndef SQLITE_MAX_PAGE_COUNT
# define SQLITE_MAX_PAGE_COUNT 0xfffffffe /* 4294967294 */
#endif

/*
** Maximum length (in bytes) of the pattern in a LIKE or GLOB
** operator.
*/
#ifndef SQLITE_MAX_LIKE_PATTERN_LENGTH

** SEH support if the -DSQLITE_OMIT_SEH option is given.
*/
#if defined(_MSC_VER) && !defined(SQLITE_OMIT_SEH)
# define SQLITE_USE_SEH 1
#else
# undef SQLITE_USE_SEH
#endif

/*
** Enable SQLITE_DIRECT_OVERFLOW_READ, unless the build explicitly
** disables it using -DSQLITE_DIRECT_OVERFLOW_READ=0
*/
#if defined(SQLITE_DIRECT_OVERFLOW_READ) && SQLITE_DIRECT_OVERFLOW_READ+1==1
  /* Disable if -DSQLITE_DIRECT_OVERFLOW_READ=0 */
# undef SQLITE_DIRECT_OVERFLOW_READ
#else
  /* In all other cases, enable */
# define SQLITE_DIRECT_OVERFLOW_READ 1
#endif


/*
** The SQLITE_THREADSAFE macro must be defined as 0, 1, or 2.
** 0 means mutexes are permanently disable and the library is never
** threadsafe.  1 means the library is serialized which is the highest
** level of threadsafety.  2 means the library is multithreaded - multiple
** threads can use SQLite as long as no two threads try to use the same

SQLITE_PRIVATE const char *sqlite3PagerFilename(const Pager*, int);
SQLITE_PRIVATE sqlite3_vfs *sqlite3PagerVfs(Pager*);
SQLITE_PRIVATE sqlite3_file *sqlite3PagerFile(Pager*);
SQLITE_PRIVATE sqlite3_file *sqlite3PagerJrnlFile(Pager*);
SQLITE_PRIVATE const char *sqlite3PagerJournalname(Pager*);
SQLITE_PRIVATE void *sqlite3PagerTempSpace(Pager*);
SQLITE_PRIVATE int sqlite3PagerIsMemdb(Pager*);
SQLITE_PRIVATE void sqlite3PagerCacheStat(Pager *, int, int, u64*);
SQLITE_PRIVATE void sqlite3PagerClearCache(Pager*);
SQLITE_PRIVATE int sqlite3SectorSize(sqlite3_file *);

/* Functions used to truncate the database file. */
SQLITE_PRIVATE void sqlite3PagerTruncateImage(Pager*,Pgno);

SQLITE_PRIVATE void sqlite3PagerRekey(DbPage*, Pgno, u16);

#define P4_EXPR       (-9) /* P4 is a pointer to an Expr tree */
#define P4_MEM        (-10) /* P4 is a pointer to a Mem*    structure */
#define P4_VTAB       (-11) /* P4 is a pointer to an sqlite3_vtab structure */
#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_INTARRAY   (-14) /* P4 is a vector of 32-bit integers */
#define P4_FUNCCTX    (-15) /* P4 is a pointer to an sqlite3_context object */
#define P4_TABLEREF   (-16) /* Like P4_TABLE, but reference counted */

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

#define OP_VCheck        174
#define OP_VInitIn       175 /* synopsis: r[P2]=ValueList(P1,P3)           */
#define OP_VColumn       176 /* synopsis: r[P3]=vcolumn(P2)                */
#define OP_VRename       177
#define OP_Pagecount     178
#define OP_MaxPgcnt      179
#define OP_ClrSubtype    180 /* synopsis: r[P1].subtype = 0                */
#define OP_GetSubtype    181 /* synopsis: r[P2] = r[P1].subtype            */
#define OP_SetSubtype    182 /* synopsis: r[P2].subtype = r[P1]            */
#define OP_FilterAdd     183 /* synopsis: filter(P1) += key(P3@P4)         */
#define OP_Trace         184
#define OP_CursorHint    185
#define OP_ReleaseReg    186 /* synopsis: release r[P1@P2] mask P3         */
#define OP_Noop          187
#define OP_Explain       188
#define OP_Abortable     189

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

/* 120 */ 0x00, 0x00, 0x40, 0x00, 0x40, 0x40, 0x10, 0x10,\
/* 128 */ 0x00, 0x00, 0x00, 0x00, 0x00, 0x40, 0x00, 0x50,\
/* 136 */ 0x00, 0x40, 0x04, 0x04, 0x00, 0x40, 0x50, 0x40,\
/* 144 */ 0x10, 0x00, 0x00, 0x10, 0x00, 0x00, 0x00, 0x00,\
/* 152 */ 0x00, 0x10, 0x00, 0x00, 0x06, 0x10, 0x00, 0x04,\
/* 160 */ 0x1a, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,\
/* 168 */ 0x00, 0x00, 0x00, 0x00, 0x00, 0x40, 0x10, 0x50,\
/* 176 */ 0x40, 0x00, 0x10, 0x10, 0x02, 0x12, 0x12, 0x00,\
/* 184 */ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,}

/* The resolve3P2Values() routine is able to run faster if it knows
** the value of the largest JUMP opcode.  The smaller the maximum
** JUMP opcode the better, so the mkopcodeh.tcl script that
** generated this include file strives to group all JUMP opcodes
** together near the beginning of the list.
*/

/*                           0x0200 -- available for reuse */
#define SQLITE_FUNC_UNLIKELY 0x0400 /* Built-in unlikely() function */
#define SQLITE_FUNC_CONSTANT 0x0800 /* Constant inputs give a constant output */
#define SQLITE_FUNC_MINMAX   0x1000 /* True for min() and max() aggregates */
#define SQLITE_FUNC_SLOCHNG  0x2000 /* "Slow Change". Value constant during a
                                    ** single query - might change over time */
#define SQLITE_FUNC_TEST     0x4000 /* Built-in testing functions */
#define SQLITE_FUNC_RUNONLY  0x8000 /* Cannot be used by valueFromFunction */
#define SQLITE_FUNC_WINDOW   0x00010000 /* Built-in window-only function */
#define SQLITE_FUNC_INTERNAL 0x00040000 /* For use by NestedParse() only */
#define SQLITE_FUNC_DIRECT   0x00080000 /* Not for use in TRIGGERs or VIEWs */
/* SQLITE_SUBTYPE            0x00100000 // Consumer of subtypes */
#define SQLITE_FUNC_UNSAFE   0x00200000 /* Function has side effects */
#define SQLITE_FUNC_INLINE   0x00400000 /* Functions implemented in-line */
#define SQLITE_FUNC_BUILTIN  0x00800000 /* This is a built-in function */
/*  SQLITE_RESULT_SUBTYPE    0x01000000 // Generator of subtypes */
#define SQLITE_FUNC_ANYORDER 0x08000000 /* count/min/max aggregate */

/* Identifier numbers for each in-line function */
#define INLINEFUNC_coalesce             0
#define INLINEFUNC_implies_nonnull_row  1
#define INLINEFUNC_expr_implies_expr    2
#define INLINEFUNC_expr_compare         3

   SQLITE_INT_TO_PTR(iArg), 0, xFunc, 0, 0, 0, #zName, {0} }
#define SFUNCTION(zName, nArg, iArg, bNC, xFunc) \
  {nArg, SQLITE_FUNC_BUILTIN|SQLITE_UTF8|SQLITE_DIRECTONLY|SQLITE_FUNC_UNSAFE, \
   SQLITE_INT_TO_PTR(iArg), 0, xFunc, 0, 0, 0, #zName, {0} }
#define MFUNCTION(zName, nArg, xPtr, xFunc) \
  {nArg, SQLITE_FUNC_BUILTIN|SQLITE_FUNC_CONSTANT|SQLITE_UTF8, \
   xPtr, 0, xFunc, 0, 0, 0, #zName, {0} }
#define JFUNCTION(zName, nArg, bUseCache, bWS, bRS, bJsonB, iArg, xFunc) \
  {nArg, SQLITE_FUNC_BUILTIN|SQLITE_DETERMINISTIC|SQLITE_FUNC_CONSTANT|\
   SQLITE_UTF8|((bUseCache)*SQLITE_FUNC_RUNONLY)|\
   ((bRS)*SQLITE_SUBTYPE)|((bWS)*SQLITE_RESULT_SUBTYPE), \
   SQLITE_INT_TO_PTR(iArg|((bJsonB)*JSON_BLOB)),0,xFunc,0, 0, 0, #zName, {0} }
#define INLINE_FUNC(zName, nArg, iArg, mFlags) \
  {nArg, SQLITE_FUNC_BUILTIN|\
   SQLITE_UTF8|SQLITE_FUNC_INLINE|SQLITE_FUNC_CONSTANT|(mFlags), \
   SQLITE_INT_TO_PTR(iArg), 0, noopFunc, 0, 0, 0, #zName, {0} }
#define TEST_FUNC(zName, nArg, iArg, mFlags) \
  {nArg, SQLITE_FUNC_BUILTIN|\
         SQLITE_UTF8|SQLITE_FUNC_INTERNAL|SQLITE_FUNC_TEST| \

  unsigned idxType:2;      /* 0:Normal 1:UNIQUE, 2:PRIMARY KEY, 3:IPK */
  unsigned bUnordered:1;   /* Use this index for == or IN queries only */
  unsigned uniqNotNull:1;  /* True if UNIQUE and NOT NULL for all columns */
  unsigned isResized:1;    /* True if resizeIndexObject() has been called */
  unsigned isCovering:1;   /* True if this is a covering index */
  unsigned noSkipScan:1;   /* Do not try to use skip-scan if true */
  unsigned hasStat1:1;     /* aiRowLogEst values come from sqlite_stat1 */
  unsigned bLowQual:1;     /* sqlite_stat1 says this is a low-quality index */
  unsigned bNoQuery:1;     /* Do not use this index to optimize queries */
  unsigned bAscKeyBug:1;   /* True if the bba7b69f9849b5bf bug applies */
  unsigned bHasVCol:1;     /* Index references one or more VIRTUAL columns */
  unsigned bHasExpr:1;     /* Index contains an expression, either a literal
                           ** expression, or a reference to a VIRTUAL column */
#ifdef SQLITE_ENABLE_STAT4
  int nSample;             /* Number of elements in aSample[] */

    Expr *pFExpr;            /* Expression encoding the function */
    FuncDef *pFunc;          /* The aggregate function implementation */
    int iDistinct;           /* Ephemeral table used to enforce DISTINCT */
    int iDistAddr;           /* Address of OP_OpenEphemeral */
    int iOBTab;              /* Ephemeral table to implement ORDER BY */
    u8 bOBPayload;           /* iOBTab has payload columns separate from key */
    u8 bOBUnique;            /* Enforce uniqueness on iOBTab keys */
    u8 bUseSubtype;          /* Transfer subtype info through sorter */
  } *aFunc;
  int nFunc;              /* Number of entries in aFunc[] */
  u32 selId;              /* Select to which this AggInfo belongs */
#ifdef SQLITE_DEBUG
  Select *pSelect;        /* SELECT statement that this AggInfo supports */
#endif
};

    Upsert *pUpsert;     /* ON CONFLICT clause information from an upsert */
    int iBaseReg;        /* For TK_REGISTER when parsing RETURNING */
  } uNC;
  NameContext *pNext;  /* Next outer name context.  NULL for outermost */
  int nRef;            /* Number of names resolved by this context */
  int nNcErr;          /* Number of errors encountered while resolving names */
  int ncFlags;         /* Zero or more NC_* flags defined below */
  u32 nNestedSelect;   /* Number of nested selects using this NC */
  Select *pWinSelect;  /* SELECT statement for any window functions */
};

/*
** Allowed values for the NameContext, ncFlags field.
**
** Value constraints (all checked via assert()):

  Parse *pParse;        /* The parse that includes the RETURNING clause */
  ExprList *pReturnEL;  /* List of expressions to return */
  Trigger retTrig;      /* The transient trigger that implements RETURNING */
  TriggerStep retTStep; /* The trigger step */
  int iRetCur;          /* Transient table holding RETURNING results */
  int nRetCol;          /* Number of in pReturnEL after expansion */
  int iRetReg;          /* Register array for holding a row of RETURNING */
  char zName[40];       /* Name of trigger: "sqlite_returning_%p" */
};

/*
** An objected used to accumulate the text of a string where we
** do not necessarily know how big the string will be in the end.
*/
struct sqlite3_str {

**       when the reference count reaches zero.
**
**   2.  Use sqlite3RCStrUnref() to free an RCStr string rather than
**       sqlite3_free()
**
**   3.  Make a (read-only) copy of a read-only RCStr string using
**       sqlite3RCStrRef().
**
** "String" is in the name, but an RCStr object can also be used to hold
** binary data.
*/
struct RCStr {
  u64 nRCRef;            /* Number of references */
  /* Total structure size should be a multiple of 8 bytes for alignment */
};

/*

  u8 bCoreMutex;                    /* True to enable core mutexing */
  u8 bFullMutex;                    /* True to enable full mutexing */
  u8 bOpenUri;                      /* True to interpret filenames as URIs */
  u8 bUseCis;                       /* Use covering indices for full-scans */
  u8 bSmallMalloc;                  /* Avoid large memory allocations if true */
  u8 bExtraSchemaChecks;            /* Verify type,name,tbl_name in schema */
  u8 bUseLongDouble;                /* Make use of long double */
#ifdef SQLITE_DEBUG
  u8 bJsonSelfcheck;                /* Double-check JSON parsing */
#endif
  int mxStrlen;                     /* Maximum string length */
  int neverCorrupt;                 /* Database is always well-formed */
  int szLookaside;                  /* Default lookaside buffer size */
  int nLookaside;                   /* Default lookaside buffer count */
  int nStmtSpill;                   /* Stmt-journal spill-to-disk threshold */
  sqlite3_mem_methods m;            /* Low-level memory allocation interface */
  sqlite3_mutex_methods mutex;      /* Low-level mutex interface */

SQLITE_PRIVATE Expr *sqlite3ExprSimplifiedAndOr(Expr*);
SQLITE_PRIVATE Expr *sqlite3ExprFunction(Parse*,ExprList*, const Token*, int);
SQLITE_PRIVATE void sqlite3ExprAddFunctionOrderBy(Parse*,Expr*,ExprList*);
SQLITE_PRIVATE void sqlite3ExprOrderByAggregateError(Parse*,Expr*);
SQLITE_PRIVATE void sqlite3ExprFunctionUsable(Parse*,const Expr*,const FuncDef*);
SQLITE_PRIVATE void sqlite3ExprAssignVarNumber(Parse*, Expr*, u32);
SQLITE_PRIVATE void sqlite3ExprDelete(sqlite3*, Expr*);
SQLITE_PRIVATE void sqlite3ExprDeleteGeneric(sqlite3*,void*);
SQLITE_PRIVATE void sqlite3ExprDeferredDelete(Parse*, Expr*);
SQLITE_PRIVATE void sqlite3ExprUnmapAndDelete(Parse*, Expr*);
SQLITE_PRIVATE ExprList *sqlite3ExprListAppend(Parse*,ExprList*,Expr*);
SQLITE_PRIVATE ExprList *sqlite3ExprListAppendVector(Parse*,ExprList*,IdList*,Expr*);
SQLITE_PRIVATE Select *sqlite3ExprListToValues(Parse*, int, ExprList*);
SQLITE_PRIVATE void sqlite3ExprListSetSortOrder(ExprList*,int,int);
SQLITE_PRIVATE void sqlite3ExprListSetName(Parse*,ExprList*,const Token*,int);
SQLITE_PRIVATE void sqlite3ExprListSetSpan(Parse*,ExprList*,const char*,const char*);
SQLITE_PRIVATE void sqlite3ExprListDelete(sqlite3*, ExprList*);
SQLITE_PRIVATE void sqlite3ExprListDeleteGeneric(sqlite3*,void*);
SQLITE_PRIVATE u32 sqlite3ExprListFlags(const ExprList*);
SQLITE_PRIVATE int sqlite3IndexHasDuplicateRootPage(Index*);
SQLITE_PRIVATE int sqlite3Init(sqlite3*, char**);
SQLITE_PRIVATE int sqlite3InitCallback(void*, int, char**, char**);
SQLITE_PRIVATE int sqlite3InitOne(sqlite3*, int, char**, u32);
SQLITE_PRIVATE void sqlite3Pragma(Parse*,Token*,Token*,Token*,int);
#ifndef SQLITE_OMIT_VIRTUALTABLE

#if SQLITE_MAX_ATTACHED>30
SQLITE_PRIVATE   int sqlite3DbMaskAllZero(yDbMask);
#endif
SQLITE_PRIVATE void sqlite3DropTable(Parse*, SrcList*, int, int);
SQLITE_PRIVATE void sqlite3CodeDropTable(Parse*, Table*, int, int);
SQLITE_PRIVATE void sqlite3DeleteTable(sqlite3*, Table*);
SQLITE_PRIVATE void sqlite3DeleteTableGeneric(sqlite3*, void*);
SQLITE_PRIVATE void sqlite3FreeIndex(sqlite3*, Index*);
#ifndef SQLITE_OMIT_AUTOINCREMENT
SQLITE_PRIVATE   void sqlite3AutoincrementBegin(Parse *pParse);
SQLITE_PRIVATE   void sqlite3AutoincrementEnd(Parse *pParse);
#else
# define sqlite3AutoincrementBegin(X)
# define sqlite3AutoincrementEnd(X)

SQLITE_PRIVATE void sqlite3CreateIndex(Parse*,Token*,Token*,SrcList*,ExprList*,int,Token*,
                          Expr*, int, int, u8);
SQLITE_PRIVATE void sqlite3DropIndex(Parse*, SrcList*, int);
SQLITE_PRIVATE int sqlite3Select(Parse*, Select*, SelectDest*);
SQLITE_PRIVATE Select *sqlite3SelectNew(Parse*,ExprList*,SrcList*,Expr*,ExprList*,
                         Expr*,ExprList*,u32,Expr*);
SQLITE_PRIVATE void sqlite3SelectDelete(sqlite3*, Select*);
SQLITE_PRIVATE void sqlite3SelectDeleteGeneric(sqlite3*,void*);
SQLITE_PRIVATE Table *sqlite3SrcListLookup(Parse*, SrcList*);
SQLITE_PRIVATE int sqlite3IsReadOnly(Parse*, Table*, Trigger*);
SQLITE_PRIVATE void sqlite3OpenTable(Parse*, int iCur, int iDb, Table*, int);
#if defined(SQLITE_ENABLE_UPDATE_DELETE_LIMIT) && !defined(SQLITE_OMIT_SUBQUERY)
SQLITE_PRIVATE Expr *sqlite3LimitWhere(Parse*,SrcList*,Expr*,ExprList*,Expr*,char*);
#endif
SQLITE_PRIVATE void sqlite3CodeChangeCount(Vdbe*,int,const char*);

SQLITE_PRIVATE int sqlite3GetUInt32(const char*, u32*);
SQLITE_PRIVATE int sqlite3Atoi(const char*);
#ifndef SQLITE_OMIT_UTF16
SQLITE_PRIVATE int sqlite3Utf16ByteLen(const void *pData, int nChar);
#endif
SQLITE_PRIVATE int sqlite3Utf8CharLen(const char *pData, int nByte);
SQLITE_PRIVATE u32 sqlite3Utf8Read(const u8**);
SQLITE_PRIVATE int sqlite3Utf8ReadLimited(const u8*, int, u32*);
SQLITE_PRIVATE LogEst sqlite3LogEst(u64);
SQLITE_PRIVATE LogEst sqlite3LogEstAdd(LogEst,LogEst);
SQLITE_PRIVATE LogEst sqlite3LogEstFromDouble(double);
SQLITE_PRIVATE u64 sqlite3LogEstToInt(LogEst);
SQLITE_PRIVATE VList *sqlite3VListAdd(sqlite3*,VList*,const char*,int,int);
SQLITE_PRIVATE const char *sqlite3VListNumToName(VList*,int);
SQLITE_PRIVATE int sqlite3VListNameToNum(VList*,const char*,int);

SQLITE_PRIVATE   int sqlite3WalDefaultHook(void*,sqlite3*,const char*,int);
#endif
#ifndef SQLITE_OMIT_CTE
SQLITE_PRIVATE   Cte *sqlite3CteNew(Parse*,Token*,ExprList*,Select*,u8);
SQLITE_PRIVATE   void sqlite3CteDelete(sqlite3*,Cte*);
SQLITE_PRIVATE   With *sqlite3WithAdd(Parse*,With*,Cte*);
SQLITE_PRIVATE   void sqlite3WithDelete(sqlite3*,With*);
SQLITE_PRIVATE   void sqlite3WithDeleteGeneric(sqlite3*,void*);
SQLITE_PRIVATE   With *sqlite3WithPush(Parse*, With*, u8);
#else
# define sqlite3CteNew(P,T,E,S)   ((void*)0)
# define sqlite3CteDelete(D,C)
# define sqlite3CteWithAdd(P,W,C) ((void*)0)
# define sqlite3WithDelete(x,y)
# define sqlite3WithPush(x,y,z) ((void*)0)

   1,                         /* bCoreMutex */
   SQLITE_THREADSAFE==1,      /* bFullMutex */
   SQLITE_USE_URI,            /* bOpenUri */
   SQLITE_ALLOW_COVERING_INDEX_SCAN,   /* bUseCis */
   0,                         /* bSmallMalloc */
   1,                         /* bExtraSchemaChecks */
   sizeof(LONGDOUBLE_TYPE)>8, /* bUseLongDouble */
#ifdef SQLITE_DEBUG
   0,                         /* bJsonSelfcheck */
#endif
   0x7ffffffe,                /* mxStrlen */
   0,                         /* neverCorrupt */
   SQLITE_DEFAULT_LOOKASIDE,  /* szLookaside, nLookaside */
   SQLITE_STMTJRNL_SPILL,     /* nStmtSpill */
   {0,0,0,0,0,0,0,0},         /* m */
   {0,0,0,0,0,0,0,0,0},       /* mutex */
   {0,0,0,0,0,0,0,0,0,0,0,0,0},/* pcache2 */

    case SQLITE_DBSTATUS_CACHE_SPILL:
      op = SQLITE_DBSTATUS_CACHE_WRITE+1;
      /* no break */ deliberate_fall_through
    case SQLITE_DBSTATUS_CACHE_HIT:
    case SQLITE_DBSTATUS_CACHE_MISS:
    case SQLITE_DBSTATUS_CACHE_WRITE:{
      int i;
      u64 nRet = 0;
      assert( SQLITE_DBSTATUS_CACHE_MISS==SQLITE_DBSTATUS_CACHE_HIT+1 );
      assert( SQLITE_DBSTATUS_CACHE_WRITE==SQLITE_DBSTATUS_CACHE_HIT+2 );

      for(i=0; i<db->nDb; i++){
        if( db->aDb[i].pBt ){
          Pager *pPager = sqlite3BtreePager(db->aDb[i].pBt);
          sqlite3PagerCacheStat(pPager, op, resetFlag, &nRet);
        }
      }
      *pHighwater = 0; /* IMP: R-42420-56072 */
                       /* IMP: R-54100-20147 */
                       /* IMP: R-29431-39229 */
      *pCurrent = (int)nRet & 0x7fffffff;
      break;
    }

    /* Set *pCurrent to non-zero if there are unresolved deferred foreign
    ** key constraints.  Set *pCurrent to zero if all foreign key constraints
    ** have been satisfied.  The *pHighwater is always set to zero.
    */

  for(i=1; i<argc; i++){
    z = sqlite3_value_text(argv[i]);
    n = sqlite3_value_bytes(argv[i]);
    if( z==0 || parseModifier(context, (char*)z, n, p, i) ) return 1;
  }
  computeJD(p);
  if( p->isError || !validJulianDay(p->iJD) ) return 1;
  if( argc==1 && p->validYMD && p->D>28 ){
    /* Make sure a YYYY-MM-DD is normalized.
    ** Example: 2023-02-31 -> 2023-03-03 */
    assert( p->validJD );
    p->validYMD = 0;
  }
  return 0;
}


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

** compiled without mutexes (SQLITE_THREADSAFE=0).
*/
SQLITE_PRIVATE void sqlite3MemoryBarrier(void){
#if defined(SQLITE_MEMORY_BARRIER)
  SQLITE_MEMORY_BARRIER;
#elif defined(__GNUC__)
  __sync_synchronize();
#elif MSVC_VERSION>=1400
  _ReadWriteBarrier();
#elif defined(MemoryBarrier)
  MemoryBarrier();
#endif
}

/*

  va_start(ap,zFormat);
  sqlite3_str_vappendf(p, zFormat, ap);
  va_end(ap);
}


/*****************************************************************************
** Reference counted string/blob storage
*****************************************************************************/

/*
** Increase the reference count of the string by one.
**
** The input parameter is returned.
*/

    case TK_BETWEEN: {
      const Expr *pX, *pY, *pZ;
      pX = pExpr->pLeft;
      assert( ExprUseXList(pExpr) );
      assert( pExpr->x.pList->nExpr==2 );
      pY = pExpr->x.pList->a[0].pExpr;
      pZ = pExpr->x.pList->a[1].pExpr;
      sqlite3TreeViewLine(pView, "BETWEEN%s", zFlgs);
      sqlite3TreeViewExpr(pView, pX, 1);
      sqlite3TreeViewExpr(pView, pY, 1);
      sqlite3TreeViewExpr(pView, pZ, 0);
      break;
    }
    case TK_TRIGGER: {
      /* If the opcode is TK_TRIGGER, then the expression is a reference

    if( c<0x80
        || (c&0xFFFFF800)==0xD800
        || (c&0xFFFFFFFE)==0xFFFE ){  c = 0xFFFD; }
  }
  return c;
}

/*
** Read a single UTF8 character out of buffer z[], but reading no
** more than n characters from the buffer.  z[] is not zero-terminated.
**
** Return the number of bytes used to construct the character.
**
** Invalid UTF8 might generate a strange result.  No effort is made
** to detect invalid UTF8.
**
** At most 4 bytes will be read out of z[].  The return value will always
** be between 1 and 4.
*/
SQLITE_PRIVATE int sqlite3Utf8ReadLimited(
  const u8 *z,
  int n,
  u32 *piOut
){
  u32 c;
  int i = 1;
  assert( n>0 );
  c = z[0];
  if( c>=0xc0 ){
    c = sqlite3Utf8Trans1[c-0xc0];
    if( n>4 ) n = 4;
    while( i<n && (z[i] & 0xc0)==0x80 ){
      c = (c<<6) + (0x3f & z[i]);
      i++;
    }
  }
  *piOut = c;
  return i;
}


/*
** If the TRANSLATE_TRACE macro is defined, the value of each Mem is
** printed on stderr on the way into and out of sqlite3VdbeMemTranslate().
*/
/* #define TRANSLATE_TRACE 1 */

/*
** Load the sqlite3.iSysErrno field if that is an appropriate thing
** to do based on the SQLite error code in rc.
*/
SQLITE_PRIVATE void sqlite3SystemError(sqlite3 *db, int rc){
  if( rc==SQLITE_IOERR_NOMEM ) return;
#if defined(SQLITE_USE_SEH) && !defined(SQLITE_OMIT_WAL)
  if( rc==SQLITE_IOERR_IN_PAGE ){
    int ii;
    int iErr;
    sqlite3BtreeEnterAll(db);
    for(ii=0; ii<db->nDb; ii++){
      if( db->aDb[ii].pBt ){
        iErr = sqlite3PagerWalSystemErrno(sqlite3BtreePager(db->aDb[ii].pBt));

    /* 174 */ "VCheck"           OpHelp(""),
    /* 175 */ "VInitIn"          OpHelp("r[P2]=ValueList(P1,P3)"),
    /* 176 */ "VColumn"          OpHelp("r[P3]=vcolumn(P2)"),
    /* 177 */ "VRename"          OpHelp(""),
    /* 178 */ "Pagecount"        OpHelp(""),
    /* 179 */ "MaxPgcnt"         OpHelp(""),
    /* 180 */ "ClrSubtype"       OpHelp("r[P1].subtype = 0"),
    /* 181 */ "GetSubtype"       OpHelp("r[P2] = r[P1].subtype"),
    /* 182 */ "SetSubtype"       OpHelp("r[P2].subtype = r[P1]"),
    /* 183 */ "FilterAdd"        OpHelp("filter(P1) += key(P3@P4)"),
    /* 184 */ "Trace"            OpHelp(""),
    /* 185 */ "CursorHint"       OpHelp(""),
    /* 186 */ "ReleaseReg"       OpHelp("release r[P1@P2] mask P3"),
    /* 187 */ "Noop"             OpHelp(""),
    /* 188 */ "Explain"          OpHelp(""),
    /* 189 */ "Abortable"        OpHelp(""),
  };
  return azName[i];
}
#endif

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

*/
static int afpUnlock(sqlite3_file *id, int eFileLock) {
  int rc = SQLITE_OK;
  unixFile *pFile = (unixFile*)id;
  unixInodeInfo *pInode;
  afpLockingContext *context = (afpLockingContext *) pFile->lockingContext;
  int skipShared = 0;




  assert( pFile );
  OSTRACE(("UNLOCK  %d %d was %d(%d,%d) pid=%d (afp)\n", pFile->h, eFileLock,
           pFile->eFileLock, pFile->pInode->eFileLock, pFile->pInode->nShared,
           osGetpid(0)));

  assert( eFileLock<=SHARED_LOCK );
  if( pFile->eFileLock<=eFileLock ){
    return SQLITE_OK;
  }
  pInode = pFile->pInode;
  sqlite3_mutex_enter(pInode->pLockMutex);
  assert( pInode->nShared!=0 );
  if( pFile->eFileLock>SHARED_LOCK ){
    assert( pInode->eFileLock==pFile->eFileLock );




#ifdef SQLITE_DEBUG
    /* When reducing a lock such that other processes can start
    ** reading the database file again, make sure that the
    ** transaction counter was updated if any part of the database
    ** file changed.  If the transaction counter is not updated,
    ** other connections to the same file might not realize that

    /* Decrement the shared lock counter.  Release the lock using an
    ** OS call only when all threads in this same process have released
    ** the lock.
    */
    unsigned long long sharedLockByte = SHARED_FIRST+pInode->sharedByte;
    pInode->nShared--;
    if( pInode->nShared==0 ){



      if( !skipShared ){
        rc = afpSetLock(context->dbPath, pFile, sharedLockByte, 1, 0);
      }
      if( !rc ){
        pInode->eFileLock = NO_LOCK;
        pFile->eFileLock = NO_LOCK;
      }

    case SQLITE_FCNTL_HAS_MOVED: {
      *(int*)pArg = fileHasMoved(pFile);
      return SQLITE_OK;
    }
#ifdef SQLITE_ENABLE_SETLK_TIMEOUT
    case SQLITE_FCNTL_LOCK_TIMEOUT: {
      int iOld = pFile->iBusyTimeout;
#if SQLITE_ENABLE_SETLK_TIMEOUT==1
      pFile->iBusyTimeout = *(int*)pArg;
#elif SQLITE_ENABLE_SETLK_TIMEOUT==2
      pFile->iBusyTimeout = !!(*(int*)pArg);
#else
# error "SQLITE_ENABLE_SETLK_TIMEOUT must be set to 1 or 2"
#endif
      *(int*)pArg = iOld;
      return SQLITE_OK;
    }
#endif
#if SQLITE_MAX_MMAP_SIZE>0
    case SQLITE_FCNTL_MMAP_SIZE: {
      i64 newLimit = *(i64*)pArg;

**
**      hShm
**      zFilename
**
** Either unixShmNode.pShmMutex must be held or unixShmNode.nRef==0 and
** unixMutexHeld() is true when reading or writing any other field
** in this structure.
**
** aLock[SQLITE_SHM_NLOCK]:
**   This array records the various locks held by clients on each of the
**   SQLITE_SHM_NLOCK slots. If the aLock[] entry is set to 0, then no
**   locks are held by the process on this slot. If it is set to -1, then
**   some client holds an EXCLUSIVE lock on the locking slot. If the aLock[]
**   value is set to a positive value, then it is the number of shared
**   locks currently held on the slot.
**
** aMutex[SQLITE_SHM_NLOCK]:
**   Normally, when SQLITE_ENABLE_SETLK_TIMEOUT is not defined, mutex
**   pShmMutex is used to protect the aLock[] array and the right to
**   call fcntl() on unixShmNode.hShm to obtain or release locks.
**
**   If SQLITE_ENABLE_SETLK_TIMEOUT is defined though, we use an array
**   of mutexes - one for each locking slot. To read or write locking
**   slot aLock[iSlot], the caller must hold the corresponding mutex
**   aMutex[iSlot]. Similarly, to call fcntl() to obtain or release a
**   lock corresponding to slot iSlot, mutex aMutex[iSlot] must be held.
*/
struct unixShmNode {
  unixInodeInfo *pInode;     /* unixInodeInfo that owns this SHM node */
  sqlite3_mutex *pShmMutex;  /* Mutex to access this object */
  char *zFilename;           /* Name of the mmapped file */
  int hShm;                  /* Open file descriptor */
  int szRegion;              /* Size of shared-memory regions */
  u16 nRegion;               /* Size of array apRegion */
  u8 isReadonly;             /* True if read-only */
  u8 isUnlocked;             /* True if no DMS lock held */
  char **apRegion;           /* Array of mapped shared-memory regions */
  int nRef;                  /* Number of unixShm objects pointing to this */
  unixShm *pFirst;           /* All unixShm objects pointing to this */
#ifdef SQLITE_ENABLE_SETLK_TIMEOUT
  sqlite3_mutex *aMutex[SQLITE_SHM_NLOCK];
#endif
  int aLock[SQLITE_SHM_NLOCK];  /* # shared locks on slot, -1==excl lock */
#ifdef SQLITE_DEBUG


  u8 nextShmId;              /* Next available unixShm.id value */
#endif
};

/*
** Structure used internally by this VFS to record the state of an
** open shared memory connection.

  int ofst,              /* First byte of the locking range */
  int n                  /* Number of bytes to lock */
){
  unixShmNode *pShmNode; /* Apply locks to this open shared-memory segment */
  struct flock f;        /* The posix advisory locking structure */
  int rc = SQLITE_OK;    /* Result code form fcntl() */


  pShmNode = pFile->pInode->pShmNode;

  /* Assert that the parameters are within expected range and that the
  ** correct mutex or mutexes are held. */
  assert( pShmNode->nRef>=0 );
  assert( (ofst==UNIX_SHM_DMS && n==1)
       || (ofst>=UNIX_SHM_BASE && ofst+n<=(UNIX_SHM_BASE+SQLITE_SHM_NLOCK))
  );
  if( ofst==UNIX_SHM_DMS ){
    assert( pShmNode->nRef>0 || unixMutexHeld() );
    assert( pShmNode->nRef==0 || sqlite3_mutex_held(pShmNode->pShmMutex) );
  }else{
#ifdef SQLITE_ENABLE_SETLK_TIMEOUT
    int ii;
    for(ii=ofst-UNIX_SHM_BASE; ii<ofst-UNIX_SHM_BASE+n; ii++){
      assert( sqlite3_mutex_held(pShmNode->aMutex[ii]) );
    }
#else
    assert( sqlite3_mutex_held(pShmNode->pShmMutex) );
    assert( pShmNode->nRef>0 );
#endif
  }

  /* 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 );
  assert( ofst>=UNIX_SHM_BASE && ofst<=(UNIX_SHM_DMS+SQLITE_SHM_NLOCK) );

  if( pShmNode->hShm>=0 ){
    int res;
    /* Initialize the locking parameters */
    f.l_type = lockType;
    f.l_whence = SEEK_SET;
    f.l_start = ofst;
    f.l_len = n;
    res = osSetPosixAdvisoryLock(pShmNode->hShm, &f, pFile);
    if( res==-1 ){
#if defined(SQLITE_ENABLE_SETLK_TIMEOUT) && SQLITE_ENABLE_SETLK_TIMEOUT==1
      rc = (pFile->iBusyTimeout ? SQLITE_BUSY_TIMEOUT : SQLITE_BUSY);
#else
      rc = SQLITE_BUSY;
#endif
    }
  }

  /* Do debug tracing */
#ifdef SQLITE_DEBUG

  OSTRACE(("SHM-LOCK "));

  if( rc==SQLITE_OK ){
    if( lockType==F_UNLCK ){
      OSTRACE(("unlock %d..%d ok\n", ofst, ofst+n-1));


    }else if( lockType==F_RDLCK ){
      OSTRACE(("read-lock %d..%d ok\n", ofst, ofst+n-1));


    }else{
      assert( lockType==F_WRLCK );
      OSTRACE(("write-lock %d..%d ok\n", ofst, ofst+n-1));


    }
  }else{
    if( lockType==F_UNLCK ){
      OSTRACE(("unlock %d..%d failed\n", ofst, ofst+n-1));
    }else if( lockType==F_RDLCK ){
      OSTRACE(("read-lock %d..%d failed\n", ofst, ofst+n-1));
    }else{
      assert( lockType==F_WRLCK );
      OSTRACE(("write-lock %d..%d failed\n", ofst, ofst+n-1));
    }



  }
#endif

  return rc;
}

/*

  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->pShmMutex);
#ifdef SQLITE_ENABLE_SETLK_TIMEOUT
    for(i=0; i<SQLITE_SHM_NLOCK; i++){
      sqlite3_mutex_free(p->aMutex[i]);
    }
#endif
    for(i=0; i<p->nRegion; i+=nShmPerMap){
      if( p->hShm>=0 ){
        osMunmap(p->apRegion[i], p->szRegion);
      }else{
        sqlite3_free(p->apRegion[i]);
      }
    }

  if( osFcntl(pShmNode->hShm, F_GETLK, &lock)!=0 ) {
    rc = SQLITE_IOERR_LOCK;
  }else if( lock.l_type==F_UNLCK ){
    if( pShmNode->isReadonly ){
      pShmNode->isUnlocked = 1;
      rc = SQLITE_READONLY_CANTINIT;
    }else{
#ifdef SQLITE_ENABLE_SETLK_TIMEOUT
      /* Do not use a blocking lock here. If the lock cannot be obtained
      ** immediately, it means some other connection is truncating the
      ** *-shm file. And after it has done so, it will not release its
      ** lock, but only downgrade it to a shared lock. So no point in
      ** blocking here. The call below to obtain the shared DMS lock may
      ** use a blocking lock. */
      int iSaveTimeout = pDbFd->iBusyTimeout;
      pDbFd->iBusyTimeout = 0;
#endif
      rc = unixShmSystemLock(pDbFd, F_WRLCK, UNIX_SHM_DMS, 1);
#ifdef SQLITE_ENABLE_SETLK_TIMEOUT
      pDbFd->iBusyTimeout = iSaveTimeout;
#endif
      /* The first connection to attach must truncate the -shm file.  We
      ** truncate to 3 bytes (an arbitrary small number, less than the
      ** -shm header size) rather than 0 as a system debugging aid, to
      ** help detect if a -shm file truncation is legitimate or is the work
      ** or a rogue process. */
      if( rc==SQLITE_OK && robust_ftruncate(pShmNode->hShm, 3) ){
        rc = unixLogError(SQLITE_IOERR_SHMOPEN,"ftruncate",pShmNode->zFilename);

    pShmNode->pInode = pDbFd->pInode;
    if( sqlite3GlobalConfig.bCoreMutex ){
      pShmNode->pShmMutex = sqlite3_mutex_alloc(SQLITE_MUTEX_FAST);
      if( pShmNode->pShmMutex==0 ){
        rc = SQLITE_NOMEM_BKPT;
        goto shm_open_err;
      }
#ifdef SQLITE_ENABLE_SETLK_TIMEOUT
      {
        int ii;
        for(ii=0; ii<SQLITE_SHM_NLOCK; ii++){
          pShmNode->aMutex[ii] = sqlite3_mutex_alloc(SQLITE_MUTEX_FAST);
          if( pShmNode->aMutex[ii]==0 ){
            rc = SQLITE_NOMEM_BKPT;
            goto shm_open_err;
          }
        }
      }
#endif
    }

    if( pInode->bProcessLock==0 ){
      if( 0==sqlite3_uri_boolean(pDbFd->zPath, "readonly_shm", 0) ){
        pShmNode->hShm = robust_open(zShm, O_RDWR|O_CREAT|O_NOFOLLOW,
                                     (sStat.st_mode&0777));
      }

** held by each client. Return true if it does, or false otherwise. This
** is to be used in an assert(). e.g.
**
**     assert( assertLockingArrayOk(pShmNode) );
*/
#ifdef SQLITE_DEBUG
static int assertLockingArrayOk(unixShmNode *pShmNode){
#ifdef SQLITE_ENABLE_SETLK_TIMEOUT
  return 1;
#else
  unixShm *pX;
  int aLock[SQLITE_SHM_NLOCK];


  memset(aLock, 0, sizeof(aLock));
  for(pX=pShmNode->pFirst; pX; pX=pX->pNext){
    int i;
    for(i=0; i<SQLITE_SHM_NLOCK; i++){
      if( pX->exclMask & (1<<i) ){
        assert( aLock[i]==0 );
        aLock[i] = -1;
      }else if( pX->sharedMask & (1<<i) ){
        assert( aLock[i]>=0 );
        aLock[i]++;
      }
    }
  }

  assert( 0==memcmp(pShmNode->aLock, aLock, sizeof(aLock)) );
  return (memcmp(pShmNode->aLock, aLock, sizeof(aLock))==0);
#endif
}
#endif

/*
** Change the lock state for a shared-memory segment.
**
** Note that the relationship between SHARED and EXCLUSIVE locks is a little
** different here than in posix.  In xShmLock(), one can go from unlocked
** to shared and back or from unlocked to exclusive and back.  But one may
** not go from shared to exclusive or from exclusive to shared.
*/
static int unixShmLock(
  sqlite3_file *fd,          /* Database file holding the shared memory */
  int ofst,                  /* First lock to acquire or release */
  int n,                     /* Number of locks to acquire or release */
  int flags                  /* What to do with the lock */
){
  unixFile *pDbFd = (unixFile*)fd;      /* Connection holding shared memory */
  unixShm *p;                           /* The shared memory being locked */
  unixShmNode *pShmNode;                /* The underlying file iNode */
  int rc = SQLITE_OK;                   /* Result code */
  u16 mask = (1<<(ofst+n)) - (1<<ofst); /* Mask of locks to take or release */
  int *aLock;

  p = pDbFd->pShm;
  if( p==0 ) return SQLITE_IOERR_SHMLOCK;
  pShmNode = p->pShmNode;
  if( NEVER(pShmNode==0) ) return SQLITE_IOERR_SHMLOCK;
  aLock = pShmNode->aLock;

  ** In other words, if this is a blocking lock, none of the locks that
  ** occur later in the above list than the lock being obtained may be
  ** held.
  **
  ** It is not permitted to block on the RECOVER lock.
  */
#ifdef SQLITE_ENABLE_SETLK_TIMEOUT
  {
    u16 lockMask = (p->exclMask|p->sharedMask);
    assert( (flags & SQLITE_SHM_UNLOCK) || pDbFd->iBusyTimeout==0 || (
          (ofst!=2)                                   /* not RECOVER */
       && (ofst!=1 || lockMask==0 || lockMask==2)
       && (ofst!=0 || lockMask<3)
       && (ofst<3  || lockMask<(1<<ofst))
    ));
  }
#endif

  /* Check if there is any work to do. There are three cases:
  **
  **    a) An unlock operation where there are locks to unlock,
  **    b) An shared lock where the requested lock is not already held
  **    c) An exclusive lock where the requested lock is not already held
  **
  ** The SQLite core never requests an exclusive lock that it already holds.
  ** This is assert()ed below.
  */
  assert( flags!=(SQLITE_SHM_EXCLUSIVE|SQLITE_SHM_LOCK)
       || 0==(p->exclMask & mask)
  );
  if( ((flags & SQLITE_SHM_UNLOCK) && ((p->exclMask|p->sharedMask) & mask))
   || (flags==(SQLITE_SHM_SHARED|SQLITE_SHM_LOCK) && 0==(p->sharedMask & mask))
   || (flags==(SQLITE_SHM_EXCLUSIVE|SQLITE_SHM_LOCK))
  ){

    /* Take the required mutexes. In SETLK_TIMEOUT mode (blocking locks), if
    ** this is an attempt on an exclusive lock use sqlite3_mutex_try(). If any
    ** other thread is holding this mutex, then it is either holding or about
    ** to hold a lock exclusive to the one being requested, and we may
    ** therefore return SQLITE_BUSY to the caller.
    **
    ** Doing this prevents some deadlock scenarios. For example, thread 1 may
    ** be a checkpointer blocked waiting on the WRITER lock. And thread 2
    ** may be a normal SQL client upgrading to a write transaction. In this
    ** case thread 2 does a non-blocking request for the WRITER lock. But -
    ** if it were to use sqlite3_mutex_enter() then it would effectively
    ** become a (doomed) blocking request, as thread 2 would block until thread
    ** 1 obtained WRITER and released the mutex. Since thread 2 already holds
    ** a lock on a read-locking slot at this point, this breaks the
    ** anti-deadlock rules (see above).  */
#ifdef SQLITE_ENABLE_SETLK_TIMEOUT
    int iMutex;
    for(iMutex=ofst; iMutex<ofst+n; iMutex++){
      if( flags==(SQLITE_SHM_LOCK|SQLITE_SHM_EXCLUSIVE) ){
        rc = sqlite3_mutex_try(pShmNode->aMutex[iMutex]);
        if( rc!=SQLITE_OK ) goto leave_shmnode_mutexes;
      }else{
        sqlite3_mutex_enter(pShmNode->aMutex[iMutex]);
      }
    }
#else
    sqlite3_mutex_enter(pShmNode->pShmMutex);
#endif

    if( ALWAYS(rc==SQLITE_OK) ){
      if( flags & SQLITE_SHM_UNLOCK ){


        /* Case (a) - unlock.  */
        int bUnlock = 1;
        assert( (p->exclMask & p->sharedMask)==0 );
        assert( !(flags & SQLITE_SHM_EXCLUSIVE) || (p->exclMask & mask)==mask );
        assert( !(flags & SQLITE_SHM_SHARED) || (p->sharedMask & mask)==mask );

        /* If this is a SHARED lock being unlocked, it is possible that other
        ** clients within this process are holding the same SHARED lock. In
        ** this case, set bUnlock to 0 so that the posix lock is not removed
        ** from the file-descriptor below.  */
        if( flags & SQLITE_SHM_SHARED ){
          assert( n==1 );
          assert( aLock[ofst]>=1 );
          if( aLock[ofst]>1 ){
            bUnlock = 0;
            aLock[ofst]--;
            p->sharedMask &= ~mask;
          }
        }

        if( bUnlock ){
          rc = unixShmSystemLock(pDbFd, F_UNLCK, ofst+UNIX_SHM_BASE, n);
          if( rc==SQLITE_OK ){
            memset(&aLock[ofst], 0, sizeof(int)*n);

            p->sharedMask &= ~mask;






            p->exclMask &= ~mask;

          }
        }
      }else if( flags & SQLITE_SHM_SHARED ){
        /* Case (b) - a shared lock.  */



        if( aLock[ofst]<0 ){
          /* An exclusive lock is held by some other connection. BUSY. */
          rc = SQLITE_BUSY;
        }else if( aLock[ofst]==0 ){
          rc = unixShmSystemLock(pDbFd, F_RDLCK, ofst+UNIX_SHM_BASE, n);
        }

        /* Get the local shared locks */
        if( rc==SQLITE_OK ){
          p->sharedMask |= mask;
          aLock[ofst]++;
        }
      }else{
        /* Case (c) - an exclusive lock.  */
        int ii;

        assert( flags==(SQLITE_SHM_LOCK|SQLITE_SHM_EXCLUSIVE) );
        assert( (p->sharedMask & mask)==0 );
        assert( (p->exclMask & mask)==0 );

        /* Make sure no sibling connections hold locks that will block this
        ** lock.  If any do, return SQLITE_BUSY right away.  */

        for(ii=ofst; ii<ofst+n; ii++){

          if( aLock[ii] ){
            rc = SQLITE_BUSY;
            break;
          }
        }

        /* Get the exclusive locks at the system level. Then if successful
        ** also update the in-memory values. */
        if( rc==SQLITE_OK ){
          rc = unixShmSystemLock(pDbFd, F_WRLCK, ofst+UNIX_SHM_BASE, n);
          if( rc==SQLITE_OK ){

            p->exclMask |= mask;
            for(ii=ofst; ii<ofst+n; ii++){
              aLock[ii] = -1;
            }
          }
        }
      }
      assert( assertLockingArrayOk(pShmNode) );
    }

    /* Drop the mutexes acquired above. */
#ifdef SQLITE_ENABLE_SETLK_TIMEOUT
  leave_shmnode_mutexes:
    for(iMutex--; iMutex>=ofst; iMutex--){
      sqlite3_mutex_leave(pShmNode->aMutex[iMutex]);
    }
#else
    sqlite3_mutex_leave(pShmNode->pShmMutex);
#endif
  }

  OSTRACE(("SHM-LOCK shmid-%d, pid-%d got %03x,%03x\n",
           p->id, osGetpid(0), p->sharedMask, p->exclMask));
  return rc;
}

/*
** Implement a memory barrier or memory fence on shared memory.

  Pgno lckPgno;               /* Page number for the locking page */
  i64 pageSize;               /* Number of bytes in a page */
  i64 journalSizeLimit;       /* Size limit for persistent journal files */
  char *zFilename;            /* Name of the database file */
  char *zJournal;             /* Name of the journal file */
  int (*xBusyHandler)(void*); /* Function to call when busy */
  void *pBusyHandlerArg;      /* Context argument for xBusyHandler */
  u32 aStat[4];               /* Total cache hits, misses, writes, spills */
#ifdef SQLITE_TEST
  int nRead;                  /* Database pages read */
#endif
  void (*xReiniter)(DbPage*); /* Call this routine when reloading pages */
  int (*xGet)(Pager*,Pgno,DbPage**,int); /* Routine to fetch a patch */
  char *pTmpSpace;            /* Pager.pageSize bytes of space for tmp use */
  PCache *pPCache;            /* Pointer to page cache object */

*/
SQLITE_PRIVATE int sqlite3PagerDirectReadOk(Pager *pPager, Pgno pgno){
  if( pPager->fd->pMethods==0 ) return 0;
  if( sqlite3PCacheIsDirty(pPager->pPCache) ) return 0;
#ifndef SQLITE_OMIT_WAL
  if( pPager->pWal ){
    u32 iRead = 0;

    (void)sqlite3WalFindFrame(pPager->pWal, pgno, &iRead);
    return iRead==0;
  }
#endif
  return 1;
}
#endif

#ifndef SQLITE_OMIT_WAL

/*
** Return the sqlite3_file for the main database given the name
** of the corresponding WAL or Journal name as passed into
** xOpen.
*/
SQLITE_API sqlite3_file *sqlite3_database_file_object(const char *zName){
  Pager *pPager;
  const char *p;
  while( zName[-1]!=0 || zName[-2]!=0 || zName[-3]!=0 || zName[-4]!=0 ){
    zName--;
  }
  p = zName - 4 - sizeof(Pager*);
  assert( EIGHT_BYTE_ALIGNMENT(p) );
  pPager = *(Pager**)p;
  return pPager->fd;
}


/*
** This function is called after transitioning from PAGER_UNLOCK to
** PAGER_SHARED state. It tests if there is a hot journal present in

      pList = sqlite3PcacheDirtyList(pPager->pPCache);
#ifdef SQLITE_ENABLE_BATCH_ATOMIC_WRITE
      if( bBatch ){
        rc = sqlite3OsFileControl(fd, SQLITE_FCNTL_BEGIN_ATOMIC_WRITE, 0);
        if( rc==SQLITE_OK ){
          rc = pager_write_pagelist(pPager, pList);
          if( rc==SQLITE_OK && pPager->dbSize>pPager->dbFileSize ){
            char *pTmp = pPager->pTmpSpace;
            int szPage = (int)pPager->pageSize;
            memset(pTmp, 0, szPage);
            rc = sqlite3OsWrite(pPager->fd, pTmp, szPage,
                      ((i64)pPager->dbSize*pPager->pageSize)-szPage);
          }
          if( rc==SQLITE_OK ){
            rc = sqlite3OsFileControl(fd, SQLITE_FCNTL_COMMIT_ATOMIC_WRITE, 0);
          }
          if( rc!=SQLITE_OK ){
            sqlite3OsFileControlHint(fd, SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE, 0);
          }
        }

  static int a[11];
  a[0] = sqlite3PcacheRefCount(pPager->pPCache);
  a[1] = sqlite3PcachePagecount(pPager->pPCache);
  a[2] = sqlite3PcacheGetCachesize(pPager->pPCache);
  a[3] = pPager->eState==PAGER_OPEN ? -1 : (int) pPager->dbSize;
  a[4] = pPager->eState;
  a[5] = pPager->errCode;
  a[6] = (int)pPager->aStat[PAGER_STAT_HIT] & 0x7fffffff;
  a[7] = (int)pPager->aStat[PAGER_STAT_MISS] & 0x7fffffff;
  a[8] = 0;  /* Used to be pPager->nOvfl */
  a[9] = pPager->nRead;
  a[10] = (int)pPager->aStat[PAGER_STAT_WRITE] & 0x7fffffff;
  return a;
}
#endif

/*
** Parameter eStat must be one of SQLITE_DBSTATUS_CACHE_HIT, _MISS, _WRITE,
** or _WRITE+1.  The SQLITE_DBSTATUS_CACHE_WRITE+1 case is a translation
** of SQLITE_DBSTATUS_CACHE_SPILL.  The _SPILL case is not contiguous because
** it was added later.
**
** Before returning, *pnVal is incremented by the
** current cache hit or miss count, according to the value of eStat. If the
** reset parameter is non-zero, the cache hit or miss count is zeroed before
** returning.
*/
SQLITE_PRIVATE void sqlite3PagerCacheStat(Pager *pPager, int eStat, int reset, u64 *pnVal){

  assert( eStat==SQLITE_DBSTATUS_CACHE_HIT
       || eStat==SQLITE_DBSTATUS_CACHE_MISS
       || eStat==SQLITE_DBSTATUS_CACHE_WRITE
       || eStat==SQLITE_DBSTATUS_CACHE_WRITE+1
  );

*/
SQLITE_PRIVATE int sqlite3PagerWalFramesize(Pager *pPager){
  assert( pPager->eState>=PAGER_READER );
  return sqlite3WalFramesize(pPager->pWal);
}
#endif

#if defined(SQLITE_USE_SEH) && !defined(SQLITE_OMIT_WAL)
SQLITE_PRIVATE int sqlite3PagerWalSystemErrno(Pager *pPager){
  return sqlite3WalSystemErrno(pPager->pWal);
}
#endif

#endif /* SQLITE_OMIT_DISKIO */

    p = 0;
  }
  *pp = p;
  return rc;
}

#ifdef SQLITE_ENABLE_SETLK_TIMEOUT


/*
** Attempt to enable blocking locks that block for nMs ms. Return 1 if
** blocking locks are successfully enabled, or 0 otherwise.
*/
static int walEnableBlockingMs(Wal *pWal, int nMs){
  int rc = sqlite3OsFileControl(
      pWal->pDbFd, SQLITE_FCNTL_LOCK_TIMEOUT, (void*)&nMs
  );
  return (rc==SQLITE_OK);
}

/*
** Attempt to enable blocking locks. Blocking locks are enabled only if (a)
** they are supported by the VFS, and (b) the database handle is configured
** with a busy-timeout. Return 1 if blocking locks are successfully enabled,
** or 0 otherwise.
*/
static int walEnableBlocking(Wal *pWal){
  int res = 0;
  if( pWal->db ){
    int tmout = pWal->db->busyTimeout;
    if( tmout ){




      res = walEnableBlockingMs(pWal, tmout);
    }
  }
  return res;
}

/*
** Disable blocking locks.

/*
** Set the database handle used to determine if blocking locks are required.
*/
SQLITE_PRIVATE void sqlite3WalDb(Wal *pWal, sqlite3 *db){
  pWal->db = db;
}











#else
# define walEnableBlocking(x) 0
# define walDisableBlocking(x)
# define walEnableBlockingMs(pWal, ms) 0
# define sqlite3WalDb(pWal, db)
#endif   /* ifdef SQLITE_ENABLE_SETLK_TIMEOUT */


/*
** Attempt to obtain the exclusive WAL lock defined by parameters lockIdx and
** n. If the attempt fails and parameter xBusy is not NULL, then it is a

    if( pWal->bShmUnreliable==0 && (pWal->readOnly & WAL_SHM_RDONLY) ){
      if( SQLITE_OK==(rc = walLockShared(pWal, WAL_WRITE_LOCK)) ){
        walUnlockShared(pWal, WAL_WRITE_LOCK);
        rc = SQLITE_READONLY_RECOVERY;
      }
    }else{
      int bWriteLock = pWal->writeLock;
      if( bWriteLock
       || 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.
            ** Disable blocking locks first.  */
            walDisableBlocking(pWal);
            rc = walIndexRecover(pWal);
            *pChanged = 1;
          }
        }
        if( bWriteLock==0 ){
          pWal->writeLock = 0;
          walUnlockExclusive(pWal, WAL_WRITE_LOCK, 1);

    pWal->bShmUnreliable = 0;
    sqlite3WalEndReadTransaction(pWal);
    *pChanged = 1;
  }
  return rc;
}

/*
** The final argument passed to walTryBeginRead() is of type (int*). The
** caller should invoke walTryBeginRead as follows:
**
**   int cnt = 0;
**   do {
**     rc = walTryBeginRead(..., &cnt);
**   }while( rc==WAL_RETRY );
**
** The final value of "cnt" is of no use to the caller. It is used by
** the implementation of walTryBeginRead() as follows:
**
**   + Each time walTryBeginRead() is called, it is incremented. Once
**     it reaches WAL_RETRY_PROTOCOL_LIMIT - indicating that walTryBeginRead()
**     has many times been invoked and failed with WAL_RETRY - walTryBeginRead()
**     returns SQLITE_PROTOCOL.
**
**   + If SQLITE_ENABLE_SETLK_TIMEOUT is defined and walTryBeginRead() failed
**     because a blocking lock timed out (SQLITE_BUSY_TIMEOUT from the OS
**     layer), the WAL_RETRY_BLOCKED_MASK bit is set in "cnt". In this case
**     the next invocation of walTryBeginRead() may omit an expected call to
**     sqlite3OsSleep(). There has already been a delay when the previous call
**     waited on a lock.
*/
#define WAL_RETRY_PROTOCOL_LIMIT 100
#ifdef SQLITE_ENABLE_SETLK_TIMEOUT
# define WAL_RETRY_BLOCKED_MASK    0x10000000
#else
# define WAL_RETRY_BLOCKED_MASK    0
#endif

/*
** Attempt to start a read transaction.  This might fail due to a race or
** other transient condition.  When that happens, it returns WAL_RETRY to
** indicate to the caller that it is safe to retry immediately.
**
** On success return SQLITE_OK.  On a permanent failure (such an
** I/O error or an SQLITE_BUSY because another process is running

** This routine uses the nBackfill and aReadMark[] fields of the header
** to select a particular WAL_READ_LOCK() that strives to let the
** checkpoint process do as much work as possible.  This routine might
** update values of the aReadMark[] array in the header, but if it does
** so it takes care to hold an exclusive lock on the corresponding
** WAL_READ_LOCK() while changing values.
*/
static int walTryBeginRead(Wal *pWal, int *pChanged, int useWal, int *pCnt){
  volatile WalCkptInfo *pInfo;    /* Checkpoint information in wal-index */
  u32 mxReadMark;                 /* Largest aReadMark[] value */
  int mxI;                        /* Index of largest aReadMark[] value */
  int i;                          /* Loop counter */
  int rc = SQLITE_OK;             /* Return code  */
  u32 mxFrame;                    /* Wal frame to lock to */
#ifdef SQLITE_ENABLE_SETLK_TIMEOUT
  int nBlockTmout = 0;
#endif

  assert( pWal->readLock<0 );     /* Not currently locked */

  /* useWal may only be set for read/write connections */
  assert( (pWal->readOnly & WAL_SHM_RDONLY)==0 || useWal==0 );

  /* Take steps to avoid spinning forever if there is a protocol error.

  ** After 5 RETRYs, we begin calling sqlite3OsSleep().  The first few
  ** calls to sqlite3OsSleep() have a delay of 1 microsecond.  Really this
  ** is more of a scheduler yield than an actual delay.  But on the 10th
  ** an subsequent retries, the delays start becoming longer and longer,
  ** so that on the 100th (and last) RETRY we delay for 323 milliseconds.
  ** The total delay time before giving up is less than 10 seconds.
  */
  (*pCnt)++;
  if( *pCnt>5 ){
    int nDelay = 1;                      /* Pause time in microseconds */
    int cnt = (*pCnt & ~WAL_RETRY_BLOCKED_MASK);
    if( cnt>WAL_RETRY_PROTOCOL_LIMIT ){
      VVA_ONLY( pWal->lockError = 1; )
      return SQLITE_PROTOCOL;
    }
    if( *pCnt>=10 ) nDelay = (cnt-9)*(cnt-9)*39;
#ifdef SQLITE_ENABLE_SETLK_TIMEOUT
    /* In SQLITE_ENABLE_SETLK_TIMEOUT builds, configure the file-descriptor
    ** to block for locks for approximately nDelay us. This affects three
    ** locks: (a) the shared lock taken on the DMS slot in os_unix.c (if
    ** using os_unix.c), (b) the WRITER lock taken in walIndexReadHdr() if the
    ** first attempted read fails, and (c) the shared lock taken on the
    ** read-mark.
    **
    ** If the previous call failed due to an SQLITE_BUSY_TIMEOUT error,
    ** then sleep for the minimum of 1us. The previous call already provided
    ** an extra delay while it was blocking on the lock.
    */
    nBlockTmout = (nDelay+998) / 1000;
    if( !useWal && walEnableBlockingMs(pWal, nBlockTmout) ){
      if( *pCnt & WAL_RETRY_BLOCKED_MASK ) nDelay = 1;
    }
#endif
    sqlite3OsSleep(pWal->pVfs, nDelay);
    *pCnt &= ~WAL_RETRY_BLOCKED_MASK;
  }

  if( !useWal ){
    assert( rc==SQLITE_OK );
    if( pWal->bShmUnreliable==0 ){
      rc = walIndexReadHdr(pWal, pChanged);
    }
#ifdef SQLITE_ENABLE_SETLK_TIMEOUT
    walDisableBlocking(pWal);
    if( rc==SQLITE_BUSY_TIMEOUT ){
      rc = SQLITE_BUSY;
      *pCnt |= WAL_RETRY_BLOCKED_MASK;
    }
#endif
    if( rc==SQLITE_BUSY ){
      /* If there is not a recovery running in another thread or process
      ** then convert BUSY errors to WAL_RETRY.  If recovery is known to
      ** be running, convert BUSY to BUSY_RECOVERY.  There is a race here
      ** which might cause WAL_RETRY to be returned even if BUSY_RECOVERY
      ** would be technically correct.  But the race is benign since with
      ** WAL_RETRY this routine will be called again and will probably be

    }
  }
  if( mxI==0 ){
    assert( rc==SQLITE_BUSY || (pWal->readOnly & WAL_SHM_RDONLY)!=0 );
    return rc==SQLITE_BUSY ? WAL_RETRY : SQLITE_READONLY_CANTINIT;
  }

  (void)walEnableBlockingMs(pWal, nBlockTmout);
  rc = walLockShared(pWal, WAL_READ_LOCK(mxI));
  walDisableBlocking(pWal);
  if( rc ){
#ifdef SQLITE_ENABLE_SETLK_TIMEOUT
    if( rc==SQLITE_BUSY_TIMEOUT ){
      *pCnt |= WAL_RETRY_BLOCKED_MASK;
    }
#else
    assert( rc!=SQLITE_BUSY_TIMEOUT );
#endif
    assert( (rc&0xFF)!=SQLITE_BUSY||rc==SQLITE_BUSY||rc==SQLITE_BUSY_TIMEOUT );
    return (rc&0xFF)==SQLITE_BUSY ? WAL_RETRY : rc;
  }
  /* Now that the read-lock has been obtained, check that neither the
  ** value in the aReadMark[] array or the contents of the wal-index
  ** header have changed.
  **
  ** It is necessary to check that the wal-index header did not change
  ** between the time it was read and when the shared-lock was obtained

      return rc;
    }
    ckptLock = 1;
  }
#endif

  do{
    rc = walTryBeginRead(pWal, pChanged, 0, &cnt);
  }while( rc==WAL_RETRY );
  testcase( (rc&0xff)==SQLITE_BUSY );
  testcase( (rc&0xff)==SQLITE_IOERR );
  testcase( rc==SQLITE_PROTOCOL );
  testcase( rc==SQLITE_OK );

#ifdef SQLITE_ENABLE_SNAPSHOT

    while( (iH = AtomicLoad(&sLoc.aHash[iKey]))!=0 ){
      u32 iFrame = iH + sLoc.iZero;
      if( iFrame<=iLast && iFrame>=pWal->minFrame && sLoc.aPgno[iH-1]==pgno ){
        assert( iFrame>iRead || CORRUPT_DB );
        iRead = iFrame;
      }
      if( (nCollide--)==0 ){
        *piRead = 0;
        return SQLITE_CORRUPT_BKPT;
      }
      iKey = walNextHash(iKey);
    }
    if( iRead ) break;
  }

      }
    }
    walUnlockShared(pWal, WAL_READ_LOCK(0));
    pWal->readLock = -1;
    cnt = 0;
    do{
      int notUsed;
      rc = walTryBeginRead(pWal, &notUsed, 1, &cnt);
    }while( rc==WAL_RETRY );
    assert( (rc&0xff)!=SQLITE_BUSY ); /* BUSY not possible when useWal==1 */
    testcase( (rc&0xff)==SQLITE_IOERR );
    testcase( rc==SQLITE_PROTOCOL );
    testcase( rc==SQLITE_OK );
  }
  return rc;

  /* EVIDENCE-OF: R-62920-47450 The busy-handler callback is never invoked
  ** in the SQLITE_CHECKPOINT_PASSIVE mode. */
  assert( eMode!=SQLITE_CHECKPOINT_PASSIVE || xBusy==0 );

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

  /* Enable blocking locks, if possible. */

  sqlite3WalDb(pWal, db);
  if( xBusy2 ) (void)walEnableBlocking(pWal);

  /* IMPLEMENTATION-OF: R-62028-47212 All calls obtain an exclusive
  ** "checkpoint" lock on the database file.
  ** 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,

    }
  }


  /* Read the wal-index header. */
  SEH_TRY {
    if( rc==SQLITE_OK ){
      /* For a passive checkpoint, do not re-enable blocking locks after
      ** reading the wal-index header. A passive checkpoint should not block
      ** or invoke the busy handler. The only lock such a checkpoint may
      ** attempt to obtain is a lock on a read-slot, and it should give up
      ** immediately and do a partial checkpoint if it cannot obtain it. */
      walDisableBlocking(pWal);
      rc = walIndexReadHdr(pWal, &isChanged);
      if( eMode2!=SQLITE_CHECKPOINT_PASSIVE ) (void)walEnableBlocking(pWal);
      if( isChanged && pWal->pDbFd->pMethods->iVersion>=3 ){
        sqlite3OsUnfetch(pWal->pDbFd, 0, 0);
      }
    }

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

**     18       1     File format write version
**     19       1     File format read version
**     20       1     Bytes of unused space at the end of each page
**     21       1     Max embedded payload fraction (must be 64)
**     22       1     Min embedded payload fraction (must be 32)
**     23       1     Min leaf payload fraction (must be 32)
**     24       4     File change counter
**     28       4     The size of the database in pages
**     32       4     First freelist page
**     36       4     Number of freelist pages in the file
**     40      60     15 4-byte meta values passed to higher layers
**
**     40       4     Schema cookie
**     44       4     File format of schema layer
**     48       4     Size of page cache

        ){
          sqlite3_file *fd = sqlite3PagerFile(pBt->pPager);
          u8 aSave[4];
          u8 *aWrite = &pBuf[-4];
          assert( aWrite>=pBufStart );                         /* due to (6) */
          memcpy(aSave, aWrite, 4);
          rc = sqlite3OsRead(fd, aWrite, a+4, (i64)pBt->pageSize*(nextPage-1));

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

        {
          DbPage *pDbPage;

** Return 1 if there are 2 or more references to the page and 0 if
** if this is the first reference to the page.
**
** Also check that the page number is in bounds.
*/
static int checkRef(IntegrityCk *pCheck, Pgno iPage){
  if( iPage>pCheck->nCkPage || iPage==0 ){

    checkAppendMsg(pCheck, "invalid page number %u", iPage);
    return 1;
  }
  if( getPageReferenced(pCheck, iPage) ){
    checkAppendMsg(pCheck, "2nd reference to page %u", iPage);
    return 1;
  }

  sCheck.mxErr = mxErr;
  sqlite3StrAccumInit(&sCheck.errMsg, 0, zErr, sizeof(zErr), SQLITE_MAX_LENGTH);
  sCheck.errMsg.printfFlags = SQLITE_PRINTF_INTERNAL;
  if( sCheck.nCkPage==0 ){
    goto integrity_ck_cleanup;
  }





  sCheck.aPgRef = sqlite3MallocZero((sCheck.nCkPage / 8)+ 1);
  if( !sCheck.aPgRef ){
    checkOom(&sCheck);
    goto integrity_ck_cleanup;

  }
  sCheck.heap = (u32*)sqlite3PageMalloc( pBt->pageSize );
  if( sCheck.heap==0 ){
    checkOom(&sCheck);
    goto integrity_ck_cleanup;
  }

  assert( !ExprHasProperty(p, EP_IntValue) );
  pFunc = sqlite3FindFunction(db, p->u.zToken, nVal, enc, 0);
#ifdef SQLITE_ENABLE_UNKNOWN_SQL_FUNCTION
  if( pFunc==0 ) return SQLITE_OK;
#endif
  assert( pFunc );
  if( (pFunc->funcFlags & (SQLITE_FUNC_CONSTANT|SQLITE_FUNC_SLOCHNG))==0
   || (pFunc->funcFlags & (SQLITE_FUNC_NEEDCOLL|SQLITE_FUNC_RUNONLY))!=0
  ){
    return SQLITE_OK;
  }

  if( pList ){
    apVal = (sqlite3_value**)sqlite3DbMallocZero(db, sizeof(apVal[0]) * nVal);
    if( apVal==0 ){

** Other useful labels for breakpoints include:
**   test_trace_breakpoint(pc,pOp)
**   sqlite3CorruptError(lineno)
**   sqlite3MisuseError(lineno)
**   sqlite3CantopenError(lineno)
*/
static void test_addop_breakpoint(int pc, Op *pOp){
  static u64 n = 0;
  (void)pc;
  (void)pOp;
  n++;
  if( n==LARGEST_UINT64 ) abort(); /* so that n is used, preventing a warning */
}
#endif

/*
** Slow paths for sqlite3VdbeAddOp3() and sqlite3VdbeAddOp4Int() for the
** unusual case when we need to increase the size of the Vdbe.aOp[] array
** before adding the new opcode.

      }
      break;
    }
    case P4_VTAB : {
      if( db->pnBytesFreed==0 ) sqlite3VtabUnlock((VTable *)p4);
      break;
    }
    case P4_TABLEREF: {
      if( db->pnBytesFreed==0 ) sqlite3DeleteTable(db, (Table*)p4);
      break;
    }
  }
}

/*
** Free the space allocated for aOp and any p4 values allocated for the
** opcodes contained within. If aOp is not NULL it is assumed to contain
** nOp entries.

static void SQLITE_NOINLINE vdbeChangeP4Full(
  Vdbe *p,
  Op *pOp,
  const char *zP4,
  int n
){
  if( pOp->p4type ){
    assert( pOp->p4type > P4_FREE_IF_LE );
    pOp->p4type = 0;
    pOp->p4.p = 0;
  }
  if( n<0 ){
    sqlite3VdbeChangeP4(p, (int)(pOp - p->aOp), zP4, n);
  }else{
    if( n==0 ) n = sqlite3Strlen30(zP4);

/*
** 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).
*/
SQLITE_PRIVATE int sqlite3IntFloatCompare(i64 i, double r){
  if( sqlite3IsNaN(r) ){
    /* SQLite considers NaN to be a NULL. And all integer values are greater
    ** than NULL */
    return 1;
  }
  if( sqlite3Config.bUseLongDouble ){
    LONGDOUBLE_TYPE x = (LONGDOUBLE_TYPE)i;
    testcase( x<r );
    testcase( x>r );
    testcase( x==r );
    return (x<r) ? -1 : (x>r);
  }else{

** Set all the parameters in the compiled SQL statement to NULL.
*/
SQLITE_API int sqlite3_clear_bindings(sqlite3_stmt *pStmt){
  int i;
  int rc = SQLITE_OK;
  Vdbe *p = (Vdbe*)pStmt;
#if SQLITE_THREADSAFE
  sqlite3_mutex *mutex;
#endif
#ifdef SQLITE_ENABLE_API_ARMOR
  if( pStmt==0 ){
    return SQLITE_MISUSE_BKPT;
  }
#endif
#if SQLITE_THREADSAFE
  mutex = p->db->mutex;
#endif
  sqlite3_mutex_enter(mutex);
  for(i=0; i<p->nVar; i++){
    sqlite3VdbeMemRelease(&p->aVar[i]);
    p->aVar[i].flags = MEM_Null;
  }
  assert( (p->prepFlags & SQLITE_PREPARE_SAVESQL)!=0 || p->expmask==0 );

  sqlite3VdbeMemSetPointer(pOut, pPtr, zPType, xDestructor);
}
SQLITE_API void sqlite3_result_subtype(sqlite3_context *pCtx, unsigned int eSubtype){
  Mem *pOut;
#ifdef SQLITE_ENABLE_API_ARMOR
  if( pCtx==0 ) return;
#endif
#if defined(SQLITE_STRICT_SUBTYPE) && SQLITE_STRICT_SUBTYPE+0!=0
  if( pCtx->pFunc!=0
   && (pCtx->pFunc->funcFlags & SQLITE_RESULT_SUBTYPE)==0
  ){
    char zErr[200];
    sqlite3_snprintf(sizeof(zErr), zErr,
                     "misuse of sqlite3_result_subtype() by %s()",
                     pCtx->pFunc->zName);
    sqlite3_result_error(pCtx, zErr, -1);
    return;
  }
#endif /* SQLITE_STRICT_SUBTYPE */
  pOut = pCtx->pOut;
  assert( sqlite3_mutex_held(pOut->db->mutex) );
  pOut->eSubtype = eSubtype & 0xff;
  pOut->flags |= MEM_Subtype;
}
SQLITE_API void sqlite3_result_text(
  sqlite3_context *pCtx,

/*
** Extract the user data from a sqlite3_context structure and return a
** pointer to it.
*/
SQLITE_API void *sqlite3_user_data(sqlite3_context *p){
#ifdef SQLITE_ENABLE_API_ARMOR
  if( p==0 ) return 0;
#endif
  assert( p && p->pFunc );

  return p->pFunc->pUserData;
}

/*
** Extract the user data from a sqlite3_context structure and return a
** pointer to it.
**

** Other useful labels for breakpoints include:
**   test_addop_breakpoint(pc,pOp)
**   sqlite3CorruptError(lineno)
**   sqlite3MisuseError(lineno)
**   sqlite3CantopenError(lineno)
*/
static void test_trace_breakpoint(int pc, Op *pOp, Vdbe *v){
  static u64 n = 0;
  (void)pc;
  (void)pOp;
  (void)v;
  n++;
  if( n==LARGEST_UINT64 ) abort(); /* So that n is used, preventing a warning */
}
#endif

/*
** Invoke the VDBE coverage callback, if that callback is defined.  This
** feature is used for test suite validation only and does not appear an
** production builds.

**
** To force any register to be an integer, just add 0.
*/
case OP_AddImm: {            /* in1 */
  pIn1 = &aMem[pOp->p1];
  memAboutToChange(p, pIn1);
  sqlite3VdbeMemIntegerify(pIn1);
  *(u64*)&pIn1->u.i += (u64)pOp->p2;
  break;
}

/* Opcode: MustBeInt P1 P2 * * *
**
** Force the value in register P1 to be an integer.  If the value
** in P1 is not an integer and cannot be converted into an integer

**
** Run the SQL statement or statements specified in the P4 string.
** Disable Auth and Trace callbacks while those statements are running if
** P1 is true.
*/
case OP_SqlExec: {
  char *zErr;
#ifndef SQLITE_OMIT_AUTHORIZATION
  sqlite3_xauth xAuth;
#endif
  u8 mTrace;

  sqlite3VdbeIncrWriteCounter(p, 0);
  db->nSqlExec++;
  zErr = 0;
#ifndef SQLITE_OMIT_AUTHORIZATION
  xAuth = db->xAuth;
#endif
  mTrace = db->mTrace;
  if( pOp->p1 ){
#ifndef SQLITE_OMIT_AUTHORIZATION
    db->xAuth = 0;
#endif
    db->mTrace = 0;
  }
  rc = sqlite3_exec(db, pOp->p4.z, 0, 0, &zErr);
  db->nSqlExec--;
#ifndef SQLITE_OMIT_AUTHORIZATION
  db->xAuth = xAuth;
#endif
  db->mTrace = mTrace;
  if( zErr || rc ){
    sqlite3VdbeError(p, "%s", zErr);
    sqlite3_free(zErr);
    if( rc==SQLITE_NOMEM ) goto no_mem;
    goto abort_due_to_error;
  }

    goto no_mem;
  }
  break;
}
#endif /* SQLITE_OMIT_VIRTUALTABLE */

#ifndef SQLITE_OMIT_VIRTUALTABLE
/* Opcode: VCheck P1 P2 P3 P4 *
**
** P4 is a pointer to a Table object that is a virtual table in schema P1
** that supports the xIntegrity() method.  This opcode runs the xIntegrity()
** method for that virtual table, using P3 as the integer argument.  If
** an error is reported back, the table name is prepended to the error
** message and that message is stored in P2.  If no errors are seen,
** register P2 is set to NULL.
*/
case OP_VCheck: {             /* out2 */
  Table *pTab;
  sqlite3_vtab *pVtab;
  const sqlite3_module *pModule;
  char *zErr = 0;

  pOut = &aMem[pOp->p2];
  sqlite3VdbeMemSetNull(pOut);  /* Innocent until proven guilty */
  assert( pOp->p4type==P4_TABLEREF );
  pTab = pOp->p4.pTab;
  assert( pTab!=0 );
  assert( pTab->nTabRef>0 );
  assert( IsVirtual(pTab) );
  if( pTab->u.vtab.p==0 ) break;
  pVtab = pTab->u.vtab.p->pVtab;
  assert( pVtab!=0 );
  pModule = pVtab->pModule;
  assert( pModule!=0 );
  assert( pModule->iVersion>=4 );
  assert( pModule->xIntegrity!=0 );

  sqlite3VtabLock(pTab->u.vtab.p);
  assert( pOp->p1>=0 && pOp->p1<db->nDb );
  rc = pModule->xIntegrity(pVtab, db->aDb[pOp->p1].zDbSName, pTab->zName,
                           pOp->p3, &zErr);
  sqlite3VtabUnlock(pTab->u.vtab.p);

  if( rc ){
    sqlite3_free(zErr);
    goto abort_due_to_error;
  }
  if( zErr ){
    sqlite3VdbeMemSetStr(pOut, zErr, -1, SQLITE_UTF8, sqlite3_free);
  }

** unused by OP_VColumn.
*/
case OP_VColumn: {           /* ncycle */
  sqlite3_vtab *pVtab;
  const sqlite3_module *pModule;
  Mem *pDest;
  sqlite3_context sContext;
  FuncDef nullFunc;

  VdbeCursor *pCur = p->apCsr[pOp->p1];
  assert( pCur!=0 );
  assert( pOp->p3>0 && pOp->p3<=(p->nMem+1 - p->nCursor) );
  pDest = &aMem[pOp->p3];
  memAboutToChange(p, pDest);
  if( pCur->nullRow ){
    sqlite3VdbeMemSetNull(pDest);
    break;
  }
  assert( pCur->eCurType==CURTYPE_VTAB );
  pVtab = pCur->uc.pVCur->pVtab;
  pModule = pVtab->pModule;
  assert( pModule->xColumn );
  memset(&sContext, 0, sizeof(sContext));
  sContext.pOut = pDest;
  sContext.enc = encoding;
  nullFunc.pUserData = 0;
  nullFunc.funcFlags = SQLITE_RESULT_SUBTYPE;
  sContext.pFunc = &nullFunc;
  assert( pOp->p5==OPFLAG_NOCHNG || pOp->p5==0 );
  if( pOp->p5 & OPFLAG_NOCHNG ){
    sqlite3VdbeMemSetNull(pDest);
    pDest->flags = MEM_Null|MEM_Zero;
    pDest->u.nZero = 0;
  }else{
    MemSetTypeFlag(pDest, MEM_Null);

** Clear the subtype from register P1.
*/
case OP_ClrSubtype: {   /* in1 */
  pIn1 = &aMem[pOp->p1];
  pIn1->flags &= ~MEM_Subtype;
  break;
}

/* Opcode: GetSubtype P1 P2 * * *
** Synopsis:  r[P2] = r[P1].subtype
**
** Extract the subtype value from register P1 and write that subtype
** into register P2.  If P1 has no subtype, then P1 gets a NULL.
*/
case OP_GetSubtype: {   /* in1 out2 */
  pIn1 = &aMem[pOp->p1];
  pOut = &aMem[pOp->p2];
  if( pIn1->flags & MEM_Subtype ){
    sqlite3VdbeMemSetInt64(pOut, pIn1->eSubtype);
  }else{
    sqlite3VdbeMemSetNull(pOut);
  }
  break;
}

/* Opcode: SetSubtype P1 P2 * * *
** Synopsis:  r[P2].subtype = r[P1]
**
** Set the subtype value of register P2 to the integer from register P1.
** If P1 is NULL, clear the subtype from p2.
*/
case OP_SetSubtype: {   /* in1 out2 */
  pIn1 = &aMem[pOp->p1];
  pOut = &aMem[pOp->p2];
  if( pIn1->flags & MEM_Null ){
    pOut->flags &= ~MEM_Subtype;
  }else{
    assert( pIn1->flags & MEM_Int );
    pOut->flags |= MEM_Subtype;
    pOut->eSubtype = (u8)(pIn1->u.i & 0xff);
  }
  break;
}

/* Opcode: FilterAdd P1 * P3 P4 *
** Synopsis: filter(P1) += key(P3@P4)
**
** Compute a hash on the P4 registers starting with r[P3] and
** add that hash to the bloom filter contained in r[P1].
*/

  int n;
  Table *pExTab;

  n = pExpr->iColumn;
  assert( ExprUseYTab(pExpr) );
  pExTab = pExpr->y.pTab;
  assert( pExTab!=0 );
  assert( n < pExTab->nCol );
  if( (pExTab->tabFlags & TF_HasGenerated)!=0
   && (pExTab->aCol[n].colFlags & COLFLAG_GENERATED)!=0
  ){
    testcase( pExTab->nCol==BMS-1 );
    testcase( pExTab->nCol==BMS );
    return pExTab->nCol>=BMS ? ALLBITS : MASKBIT(pExTab->nCol)-1;
  }else{

      sqlite3ErrorMsg(pParse, "%s: %s.%s", zErr, zTab, zCol);
    }else{
      sqlite3ErrorMsg(pParse, "%s: %s", zErr, zCol);
    }
    sqlite3RecordErrorOffsetOfExpr(pParse->db, pExpr);
    pParse->checkSchema = 1;
    pTopNC->nNcErr++;
    eNewExprOp = TK_NULL;
  }
  assert( pFJMatch==0 );

  /* Remove all substructure from pExpr */
  if( !ExprHasProperty(pExpr,(EP_TokenOnly|EP_Leaf)) ){
    sqlite3ExprDelete(db, pExpr->pLeft);
    pExpr->pLeft = 0;

  ** if the mask contains extra set bits.  However, it is important to
  ** avoid setting bits beyond the maximum column number of the table.
  ** (See ticket [b92e5e8ec2cdbaa1]).
  **
  ** If a generated column is referenced, set bits for every column
  ** of the table.
  */
  if( pExpr->iColumn>=0 && cnt==1 && pMatch!=0 ){
    pMatch->colUsed |= sqlite3ExprColUsed(pExpr);
  }

  pExpr->op = eNewExprOp;
lookupname_end:
  if( cnt==1 ){
    assert( pNC!=0 );

            sqlite3WalkExpr(pWalker, pExpr->y.pWin->pFilter);
          }
#endif
          pNC2 = pNC;
          while( pNC2
              && sqlite3ReferencesSrcList(pParse, pExpr, pNC2->pSrcList)==0
          ){
            pExpr->op2 += (1 + pNC2->nNestedSelect);
            pNC2 = pNC2->pNext;
          }
          assert( pDef!=0 || IN_RENAME_OBJECT );
          if( pNC2 && pDef ){
            pExpr->op2 += pNC2->nNestedSelect;
            assert( SQLITE_FUNC_MINMAX==NC_MinMaxAgg );
            assert( SQLITE_FUNC_ANYORDER==NC_OrderAgg );
            testcase( (pDef->funcFlags & SQLITE_FUNC_MINMAX)!=0 );
            testcase( (pDef->funcFlags & SQLITE_FUNC_ANYORDER)!=0 );
            pNC2->ncFlags |= NC_HasAgg
              | ((pDef->funcFlags^SQLITE_FUNC_ANYORDER)
                  & (SQLITE_FUNC_MINMAX|SQLITE_FUNC_ANYORDER));

      assert( pSub->pPrior && pSub->pOrderBy==0 );
      pSub->pOrderBy = p->pOrderBy;
      p->pOrderBy = 0;
    }

    /* Recursively resolve names in all subqueries in the FROM clause
    */
    if( pOuterNC ) pOuterNC->nNestedSelect++;
    for(i=0; i<p->pSrc->nSrc; i++){
      SrcItem *pItem = &p->pSrc->a[i];
      if( pItem->pSelect && (pItem->pSelect->selFlags & SF_Resolved)==0 ){
        int nRef = pOuterNC ? pOuterNC->nRef : 0;
        const char *zSavedContext = pParse->zAuthContext;

        if( pItem->zName ) pParse->zAuthContext = pItem->zName;

        ** the refcount on all contexts between the current one and the
        ** context containing the column when it resolves a name. */
        if( pOuterNC ){
          assert( pItem->fg.isCorrelated==0 && pOuterNC->nRef>=nRef );
          pItem->fg.isCorrelated = (pOuterNC->nRef>nRef);
        }
      }
    }
    if( pOuterNC && ALWAYS(pOuterNC->nNestedSelect>0) ){
      pOuterNC->nNestedSelect--;
    }

    /* Set up the local name-context to pass to sqlite3ResolveExprNames() to
    ** resolve the result-set expression list.
    */
    sNC.ncFlags = NC_AllowAgg|NC_AllowWin;
    sNC.pSrcList = p->pSrc;

    return;
  }
  assert( pExpr->op==TK_FUNCTION );
  assert( pExpr->pLeft==0 );
  assert( ExprUseXList(pExpr) );
  if( pExpr->x.pList==0 || NEVER(pExpr->x.pList->nExpr==0) ){
    /* Ignore ORDER BY on zero-argument aggregates */
    sqlite3ParserAddCleanup(pParse, sqlite3ExprListDeleteGeneric, pOrderBy);


    return;
  }
  if( IsWindowFunc(pExpr) ){
    sqlite3ExprOrderByAggregateError(pParse, pExpr);
    sqlite3ExprListDelete(db, pOrderBy);
    return;
  }

  if( !ExprHasProperty(p, EP_Static) ){
    sqlite3DbNNFreeNN(db, p);
  }
}
SQLITE_PRIVATE void sqlite3ExprDelete(sqlite3 *db, Expr *p){
  if( p ) sqlite3ExprDeleteNN(db, p);
}
SQLITE_PRIVATE void sqlite3ExprDeleteGeneric(sqlite3 *db, void *p){
  if( ALWAYS(p) ) sqlite3ExprDeleteNN(db, (Expr*)p);
}

/*
** Clear both elements of an OnOrUsing object
*/
SQLITE_PRIVATE void sqlite3ClearOnOrUsing(sqlite3 *db, OnOrUsing *p){
  if( p==0 ){
    /* Nothing to clear */

**
** The pExpr might be deleted immediately on an OOM error.
**
** The deferred delete is (currently) implemented by adding the
** pExpr to the pParse->pConstExpr list with a register number of 0.
*/
SQLITE_PRIVATE void sqlite3ExprDeferredDelete(Parse *pParse, Expr *pExpr){
  sqlite3ParserAddCleanup(pParse, sqlite3ExprDeleteGeneric, pExpr);


}

/* Invoke sqlite3RenameExprUnmap() and sqlite3ExprDelete() on the
** expression.
*/
SQLITE_PRIVATE void sqlite3ExprUnmapAndDelete(Parse *pParse, Expr *p){
  if( p ){

    }
    if( dupFlags ){
      assert( (int)(sEdupBuf.zEnd - sEdupBuf.zAlloc) >= nNewSize+nToken );
      assert( ExprHasProperty(p, EP_Reduced)==0 );
      memcpy(sEdupBuf.zAlloc, p, nNewSize);
    }else{
      u32 nSize = (u32)exprStructSize(p);
      assert( (int)(sEdupBuf.zEnd - sEdupBuf.zAlloc) >=
                                                   (int)EXPR_FULLSIZE+nToken );
      memcpy(sEdupBuf.zAlloc, p, nSize);
      if( nSize<EXPR_FULLSIZE ){
        memset(&sEdupBuf.zAlloc[nSize], 0, EXPR_FULLSIZE-nSize);
      }
      nNewSize = EXPR_FULLSIZE;
    }

    pItem++;
  }while( --i>0 );
  sqlite3DbNNFreeNN(db, pList);
}
SQLITE_PRIVATE void sqlite3ExprListDelete(sqlite3 *db, ExprList *pList){
  if( pList ) exprListDeleteNN(db, pList);
}
SQLITE_PRIVATE void sqlite3ExprListDeleteGeneric(sqlite3 *db, void *pList){
  if( ALWAYS(pList) ) exprListDeleteNN(db, (ExprList*)pList);
}

/*
** Return the bitwise-OR of all Expr.flags fields in the given
** ExprList.
*/
SQLITE_PRIVATE u32 sqlite3ExprListFlags(const ExprList *pList){
  int i;

    case TK_STRING:
    case TK_FLOAT:
    case TK_BLOB:
      return 0;
    case TK_COLUMN:
      assert( ExprUseYTab(p) );
      return ExprHasProperty(p, EP_CanBeNull) ||
             NEVER(p->y.pTab==0) ||  /* Reference to column of index on expr */
             (p->iColumn>=0
              && p->y.pTab->aCol!=0 /* Possible due to prior error */
              && ALWAYS(p->iColumn<p->y.pTab->nCol)
              && p->y.pTab->aCol[p->iColumn].notNull==0);
    default:
      return 1;
  }
}

/*

  assert( pExpr==0 || !ExprHasVVAProperty(pExpr,EP_Immutable) );
  assert( target>0 && target<=pParse->nMem );
  assert( pParse->pVdbe!=0 || pParse->db->mallocFailed );
  if( pParse->pVdbe==0 ) return;
  inReg = sqlite3ExprCodeTarget(pParse, pExpr, target);
  if( inReg!=target ){
    u8 op;
    Expr *pX = sqlite3ExprSkipCollateAndLikely(pExpr);
    testcase( pX!=pExpr );
    if( ALWAYS(pX)
     && (ExprHasProperty(pX,EP_Subquery) || pX->op==TK_REGISTER)
    ){
      op = OP_Copy;
    }else{
      op = OP_SCopy;
    }
    sqlite3VdbeAddOp2(pParse->pVdbe, op, inReg, target);
  }

/*
** Like sqlite3ExprCompare() except COLLATE operators at the top-level
** are ignored.
*/
SQLITE_PRIVATE int sqlite3ExprCompareSkip(Expr *pA,Expr *pB, int iTab){
  return sqlite3ExprCompare(0,
             sqlite3ExprSkipCollate(pA),
             sqlite3ExprSkipCollate(pB),
             iTab);
}

/*
** Return non-zero if Expr p can only be true if pNN is not NULL.
**
** Or if seenNot is true, return non-zero if Expr p can only be

        } /* end loop over pSrcList */
      }
      return WRC_Continue;
    }
    case TK_AGG_FUNCTION: {
      if( (pNC->ncFlags & NC_InAggFunc)==0
       && pWalker->walkerDepth==pExpr->op2
       && pExpr->pAggInfo==0
      ){
        /* Check to see if pExpr is a duplicate of another aggregate
        ** function that is already in the pAggInfo structure
        */
        struct AggInfo_func *pItem = pAggInfo->aFunc;
        for(i=0; i<pAggInfo->nFunc; i++, pItem++){
          if( NEVER(pItem->pFExpr==pExpr) ) break;
          if( sqlite3ExprCompare(0, pItem->pFExpr, pExpr, -1)==0 ){
            break;
          }
        }
        if( i>=pAggInfo->nFunc ){
          /* pExpr is original.  Make a new entry in pAggInfo->aFunc[]
          */

              ExprList *pOBList;
              assert( nArg>0 );
              assert( pExpr->pLeft->op==TK_ORDER );
              assert( ExprUseXList(pExpr->pLeft) );
              pItem->iOBTab = pParse->nTab++;
              pOBList = pExpr->pLeft->x.pList;
              assert( pOBList->nExpr>0 );
              assert( pItem->bOBUnique==0 );
              if( pOBList->nExpr==1
               && nArg==1
               && sqlite3ExprCompare(0,pOBList->a[0].pExpr,
                               pExpr->x.pList->a[0].pExpr,0)==0
              ){
                pItem->bOBPayload = 0;
                pItem->bOBUnique = ExprHasProperty(pExpr, EP_Distinct);
              }else{
                pItem->bOBPayload = 1;
              }
              pItem->bUseSubtype =
                    (pItem->pFunc->funcFlags & SQLITE_SUBTYPE)!=0;
            }else{
              pItem->iOBTab = -1;
            }
            if( ExprHasProperty(pExpr, EP_Distinct) && !pItem->bOBUnique ){
              pItem->iDistinct = pParse->nTab++;
            }else{
              pItem->iDistinct = -1;

** Three SQL functions - stat_init(), stat_push(), and stat_get() -
** share an instance of the following structure to hold their state
** information.
*/
typedef struct StatAccum StatAccum;
typedef struct StatSample StatSample;
struct StatSample {

  tRowcnt *anDLt;                 /* sqlite_stat4.nDLt */
#ifdef SQLITE_ENABLE_STAT4
  tRowcnt *anEq;                  /* sqlite_stat4.nEq */
  tRowcnt *anLt;                  /* sqlite_stat4.nLt */
  union {
    i64 iRowid;                     /* Rowid in main table of the key */
    u8 *aRowid;                     /* Key for WITHOUT ROWID tables */
  } u;
  u32 nRowid;                     /* Sizeof aRowid[] */
  u8 isPSample;                   /* True if a periodic sample */

  nColUp = sizeof(tRowcnt)<8 ? (nCol+1)&~1 : nCol;
  nKeyCol = sqlite3_value_int(argv[1]);
  assert( nKeyCol<=nCol );
  assert( nKeyCol>0 );

  /* Allocate the space required for the StatAccum object */
  n = sizeof(*p)

    + sizeof(tRowcnt)*nColUp;                    /* StatAccum.anDLt */
#ifdef SQLITE_ENABLE_STAT4
  n += sizeof(tRowcnt)*nColUp;                   /* StatAccum.anEq */
  if( mxSample ){
    n += sizeof(tRowcnt)*nColUp                  /* StatAccum.anLt */
      + sizeof(StatSample)*(nCol+mxSample)       /* StatAccum.aBest[], a[] */
      + sizeof(tRowcnt)*3*nColUp*(nCol+mxSample);
  }
#endif
  p = sqlite3DbMallocZero(db, n);
  if( p==0 ){
    sqlite3_result_error_nomem(context);
    return;
  }

  p->db = db;
  p->nEst = sqlite3_value_int64(argv[2]);
  p->nRow = 0;
  p->nLimit = sqlite3_value_int64(argv[3]);
  p->nCol = nCol;
  p->nKeyCol = nKeyCol;
  p->nSkipAhead = 0;
  p->current.anDLt = (tRowcnt*)&p[1];


#ifdef SQLITE_ENABLE_STAT4
  p->current.anEq = &p->current.anDLt[nColUp];
  p->mxSample = p->nLimit==0 ? mxSample : 0;
  if( mxSample ){
    u8 *pSpace;                     /* Allocated space not yet assigned */
    int i;                          /* Used to iterate through p->aSample[] */

    p->iGet = -1;
    p->nPSample = (tRowcnt)(p->nEst/(mxSample/3+1) + 1);

  UNUSED_PARAMETER( argc );
  UNUSED_PARAMETER( context );
  assert( p->nCol>0 );
  assert( iChng<p->nCol );

  if( p->nRow==0 ){
    /* This is the first call to this function. Do initialization. */
#ifdef SQLITE_ENABLE_STAT4
    for(i=0; i<p->nCol; i++) p->current.anEq[i] = 1;
#endif
  }else{
    /* Second and subsequent calls get processed here */
#ifdef SQLITE_ENABLE_STAT4
    if( p->mxSample ) samplePushPrevious(p, iChng);
#endif

    /* Update anDLt[], anLt[] and anEq[] to reflect the values that apply
    ** to the current row of the index. */
#ifdef SQLITE_ENABLE_STAT4
    for(i=0; i<iChng; i++){
      p->current.anEq[i]++;
    }
#endif
    for(i=iChng; i<p->nCol; i++){
      p->current.anDLt[i]++;
#ifdef SQLITE_ENABLE_STAT4
      if( p->mxSample ) p->current.anLt[i] += p->current.anEq[i];

      p->current.anEq[i] = 1;
#endif
    }
  }

  p->nRow++;
#ifdef SQLITE_ENABLE_STAT4
  if( p->mxSample ){
    tRowcnt nLt;

    sqlite3_str_appendf(&sStat, "%llu",
        p->nSkipAhead ? (u64)p->nEst : (u64)p->nRow);
    for(i=0; i<p->nKeyCol; i++){
      u64 nDistinct = p->current.anDLt[i] + 1;
      u64 iVal = (p->nRow + nDistinct - 1) / nDistinct;
      if( iVal==2 && p->nRow*10 <= nDistinct*11 ) iVal = 1;
      sqlite3_str_appendf(&sStat, " %llu", iVal);
#ifdef SQLITE_ENABLE_STAT4
      assert( p->current.anEq[i] );
#endif
    }
    sqlite3ResultStrAccum(context, &sStat);
  }
#ifdef SQLITE_ENABLE_STAT4
  else if( eCall==STAT_GET_ROWID ){
    if( p->iGet<0 ){
      samplePushPrevious(p, 0);

      else if( sqlite3_strglob("costmult=[0-9]*",z)==0 ){
        pIndex->pTable->costMult = sqlite3LogEst(sqlite3Atoi(z+9));
      }
#endif
      while( z[0]!=0 && z[0]!=' ' ) z++;
      while( z[0]==' ' ) z++;
    }

    /* Set the bLowQual flag if the peak number of rows obtained
    ** from a full equality match is so large that a full table scan
    ** seems likely to be faster than using the index.
    */
    if( aLog[0] > 66              /* Index has more than 100 rows */
     && aLog[0] <= aLog[nOut-1]   /* And only a single value seen */
    ){
      pIndex->bLowQual = 1;
    }
  }
}

/*
** This callback is invoked once for each index when reading the
** sqlite_stat1 table.
**

/*
** Return the expression associated with a column.  The expression might be
** the DEFAULT clause or the AS clause of a generated column.
** Return NULL if the column has no associated expression.
*/
SQLITE_PRIVATE Expr *sqlite3ColumnExpr(Table *pTab, Column *pCol){
  if( pCol->iDflt==0 ) return 0;
  if( !IsOrdinaryTable(pTab) ) return 0;
  if( NEVER(pTab->u.tab.pDfltList==0) ) return 0;
  if( NEVER(pTab->u.tab.pDfltList->nExpr<pCol->iDflt) ) return 0;
  return pTab->u.tab.pDfltList->a[pCol->iDflt-1].pExpr;
}

/*
** Set the collating sequence name for a column.

}
SQLITE_PRIVATE void sqlite3DeleteTable(sqlite3 *db, Table *pTable){
  /* Do not delete the table until the reference count reaches zero. */
  assert( db!=0 );
  if( !pTable ) return;
  if( db->pnBytesFreed==0 && (--pTable->nTabRef)>0 ) return;
  deleteTable(db, pTable);
}
SQLITE_PRIVATE void sqlite3DeleteTableGeneric(sqlite3 *db, void *pTable){
  sqlite3DeleteTable(db, (Table*)pTable);
}


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

    if( pTab ) pTab->tabFlags |= TF_HasHidden;
  }else if( pTab && pCol!=pTab->aCol && (pCol[-1].colFlags & COLFLAG_HIDDEN) ){
    pTab->tabFlags |= TF_OOOHidden;
  }
}
#endif








/*
** Clean up the data structures associated with the RETURNING clause.
*/
static void sqlite3DeleteReturning(sqlite3 *db, void *pArg){
  Returning *pRet = (Returning*)pArg;
  Hash *pHash;
  pHash = &(db->aDb[1].pSchema->trigHash);
  sqlite3HashInsert(pHash, pRet->zName, 0);
  sqlite3ExprListDelete(db, pRet->pReturnEL);
  sqlite3DbFree(db, pRet);
}

/*
** Add the RETURNING clause to the parse currently underway.
**

  if( pRet==0 ){
    sqlite3ExprListDelete(db, pList);
    return;
  }
  pParse->u1.pReturning = pRet;
  pRet->pParse = pParse;
  pRet->pReturnEL = pList;
  sqlite3ParserAddCleanup(pParse, sqlite3DeleteReturning, pRet);

  testcase( pParse->earlyCleanup );
  if( db->mallocFailed ) return;
  sqlite3_snprintf(sizeof(pRet->zName), pRet->zName,
                   "sqlite_returning_%p", pParse);
  pRet->retTrig.zName = pRet->zName;
  pRet->retTrig.op = TK_RETURNING;
  pRet->retTrig.tr_tm = TRIGGER_AFTER;
  pRet->retTrig.bReturning = 1;
  pRet->retTrig.pSchema = db->aDb[1].pSchema;
  pRet->retTrig.pTabSchema = db->aDb[1].pSchema;
  pRet->retTrig.step_list = &pRet->retTStep;
  pRet->retTStep.op = TK_RETURNING;
  pRet->retTStep.pTrig = &pRet->retTrig;
  pRet->retTStep.pExprList = pList;
  pHash = &(db->aDb[1].pSchema->trigHash);
  assert( sqlite3HashFind(pHash, pRet->zName)==0
          || pParse->nErr  || pParse->ifNotExists );
  if( sqlite3HashInsert(pHash, pRet->zName, &pRet->retTrig)
          ==&pRet->retTrig ){
    sqlite3OomFault(db);
  }
}

/*
** Add a new column to the table currently being constructed.

SQLITE_PRIVATE char sqlite3AffinityType(const char *zIn, Column *pCol){
  u32 h = 0;
  char aff = SQLITE_AFF_NUMERIC;
  const char *zChar = 0;

  assert( zIn!=0 );
  while( zIn[0] ){
    u8 x = *(u8*)zIn;
    h = (h<<8) + sqlite3UpperToLower[x];
    zIn++;
    if( h==(('c'<<24)+('h'<<16)+('a'<<8)+'r') ){             /* CHAR */
      aff = SQLITE_AFF_TEXT;
      zChar = zIn;
    }else if( h==(('c'<<24)+('l'<<16)+('o'<<8)+'b') ){       /* CLOB */
      aff = SQLITE_AFF_TEXT;
    }else if( h==(('t'<<24)+('e'<<16)+('x'<<8)+'t') ){       /* TEXT */

    }
    sqlite3DbFree(db, zColl);
  }
  iDb = sqlite3TwoPartName(pParse, pName1, pName2, &pObjName);
  if( iDb<0 ) return;
  z = sqlite3NameFromToken(db, pObjName);
  if( z==0 ) return;
  zDb = pName2->n ? db->aDb[iDb].zDbSName : 0;
  pTab = sqlite3FindTable(db, z, zDb);
  if( pTab ){
    reindexTable(pParse, pTab, 0);
    sqlite3DbFree(db, z);
    return;
  }
  pIndex = sqlite3FindIndex(db, z, zDb);
  sqlite3DbFree(db, z);
  if( pIndex ){
    iDb = sqlite3SchemaToIndex(db, pIndex->pTable->pSchema);
    sqlite3BeginWriteOperation(pParse, 0, iDb);
    sqlite3RefillIndex(pParse, pIndex, -1);
    return;
  }
  sqlite3ErrorMsg(pParse, "unable to identify the object to be reindexed");
}
#endif

  if( pWith ){
    int i;
    for(i=0; i<pWith->nCte; i++){
      cteClear(db, &pWith->a[i]);
    }
    sqlite3DbFree(db, pWith);
  }
}
SQLITE_PRIVATE void sqlite3WithDeleteGeneric(sqlite3 *db, void *pWith){
  sqlite3WithDelete(db, (With*)pWith);
}
#endif /* !defined(SQLITE_OMIT_CTE) */

/************** End of build.c ***********************************************/
/************** Begin file callback.c ****************************************/
/*
** 2005 May 23

  const char *(*db_name)(sqlite3*,int);
  /* Version 3.40.0 and later */
  int (*value_encoding)(sqlite3_value*);
  /* Version 3.41.0 and later */
  int (*is_interrupted)(sqlite3*);
  /* Version 3.43.0 and later */
  int (*stmt_explain)(sqlite3_stmt*,int);
  /* Version 3.44.0 and later */
  void *(*get_clientdata)(sqlite3*,const char*);
  int (*set_clientdata)(sqlite3*, const char*, void*, void(*)(void*));
};

/*
** This is the function signature used for all extension entry points.  It
** is also defined in the file "loadext.c".
*/
typedef int (*sqlite3_loadext_entry)(

#define sqlite3_db_name                sqlite3_api->db_name
/* Version 3.40.0 and later */
#define sqlite3_value_encoding         sqlite3_api->value_encoding
/* Version 3.41.0 and later */
#define sqlite3_is_interrupted         sqlite3_api->is_interrupted
/* Version 3.43.0 and later */
#define sqlite3_stmt_explain           sqlite3_api->stmt_explain
/* Version 3.44.0 and later */
#define sqlite3_get_clientdata         sqlite3_api->get_clientdata
#define sqlite3_set_clientdata         sqlite3_api->set_clientdata
#endif /* !defined(SQLITE_CORE) && !defined(SQLITE_OMIT_LOAD_EXTENSION) */

#if !defined(SQLITE_CORE) && !defined(SQLITE_OMIT_LOAD_EXTENSION)
  /* This case when the file really is being compiled as a loadable
  ** extension */
# define SQLITE_EXTENSION_INIT1     const sqlite3_api_routines *sqlite3_api=0;
# define SQLITE_EXTENSION_INIT2(v)  sqlite3_api=v;

#endif
  sqlite3_db_name,
  /* Version 3.40.0 and later */
  sqlite3_value_encoding,
  /* Version 3.41.0 and later */
  sqlite3_is_interrupted,
  /* Version 3.43.0 and later */
  sqlite3_stmt_explain,
  /* Version 3.44.0 and later */
  sqlite3_get_clientdata,
  sqlite3_set_clientdata
};

/* True if x is the directory separator character
*/
#if SQLITE_OS_WIN
# define DirSep(X)  ((X)=='/'||(X)=='\\')
#else

          sqlite3ViewGetColumnNames(pParse, pTab);
          if( pTab->u.vtab.p==0 ) continue;
          pVTab = pTab->u.vtab.p->pVtab;
          if( NEVER(pVTab==0) ) continue;
          if( NEVER(pVTab->pModule==0) ) continue;
          if( pVTab->pModule->iVersion<4 ) continue;
          if( pVTab->pModule->xIntegrity==0 ) continue;
          sqlite3VdbeAddOp3(v, OP_VCheck, i, 3, isQuick);
          pTab->nTabRef++;
          sqlite3VdbeAppendP4(v, pTab, P4_TABLEREF);
          a1 = sqlite3VdbeAddOp1(v, OP_IsNull, 3); VdbeCoverage(v);
          integrityCheckResultRow(v);
          sqlite3VdbeJumpHere(v, a1);
#endif
          continue;
        }
        if( isQuick || HasRowid(pTab) ){

  }while( (rc==SQLITE_ERROR_RETRY && (cnt++)<SQLITE_MAX_PREPARE_RETRY)
       || (rc==SQLITE_SCHEMA && (sqlite3ResetOneSchema(db,-1), cnt++)==0) );
  sqlite3BtreeLeaveAll(db);
  rc = sqlite3ApiExit(db, rc);
  assert( (rc&db->errMask)==rc );
  db->busyHandler.nBusy = 0;
  sqlite3_mutex_leave(db->mutex);
  assert( rc==SQLITE_OK || (*ppStmt)==0 );
  return rc;
}


/*
** Rerun the compilation of a statement after a schema change.
**

/*
** Delete the given Select structure and all of its substructures.
*/
SQLITE_PRIVATE void sqlite3SelectDelete(sqlite3 *db, Select *p){
  if( OK_IF_ALWAYS_TRUE(p) ) clearSelect(db, p, 1);
}
SQLITE_PRIVATE void sqlite3SelectDeleteGeneric(sqlite3 *db, void *p){
  if( ALWAYS(p) ) clearSelect(db, (Select*)p, 1);
}

/*
** Return a pointer to the right-most SELECT statement in a compound.
*/
static Select *findRightmost(Select *p){
  while( p->pNext ) p = p->pNext;

  CollSeq *pColl;
  int i,j;
  Expr *p;
  struct ExprList_item *a;
  NameContext sNC;

  assert( pSelect!=0 );
  testcase( (pSelect->selFlags & SF_Resolved)==0 );
  assert( (pSelect->selFlags & SF_Resolved)!=0 || IN_RENAME_OBJECT );
  assert( pTab->nCol==pSelect->pEList->nExpr || pParse->nErr>0 );
  assert( aff==SQLITE_AFF_NONE || aff==SQLITE_AFF_BLOB );
  if( db->mallocFailed || IN_RENAME_OBJECT ) return;
  while( pSelect->pPrior ) pSelect = pSelect->pPrior;
  a = pSelect->pEList->a;
  memset(&sNC, 0, sizeof(sNC));
  sNC.pSrcList = pSelect->pSrc;

    sqlite3KeyInfoUnref(pKeyInfo);
  }

multi_select_end:
  pDest->iSdst = dest.iSdst;
  pDest->nSdst = dest.nSdst;
  if( pDelete ){
    sqlite3ParserAddCleanup(pParse, sqlite3SelectDeleteGeneric, pDelete);


  }
  return rc;
}
#endif /* SQLITE_OMIT_COMPOUND_SELECT */

/*
** Error message for when two or more terms of a compound select have different

  /* Jump to the this point in order to terminate the query.
  */
  sqlite3VdbeResolveLabel(v, labelEnd);

  /* Make arrangements to free the 2nd and subsequent arms of the compound
  ** after the parse has finished */
  if( pSplit->pPrior ){
    sqlite3ParserAddCleanup(pParse, sqlite3SelectDeleteGeneric, pSplit->pPrior);

  }
  pSplit->pPrior = pPrior;
  pPrior->pNext = pSplit;
  sqlite3ExprListDelete(db, pPrior->pOrderBy);
  pPrior->pOrderBy = 0;

  /*** TBD:  Insert subroutine calls to close cursors on incomplete

  **
  ** pSubitem->pTab is always non-NULL by test restrictions and tests above.
  */
  if( ALWAYS(pSubitem->pTab!=0) ){
    Table *pTabToDel = pSubitem->pTab;
    if( pTabToDel->nTabRef==1 ){
      Parse *pToplevel = sqlite3ParseToplevel(pParse);
      sqlite3ParserAddCleanup(pToplevel, sqlite3DeleteTableGeneric, pTabToDel);


      testcase( pToplevel->earlyCleanup );
    }else{
      pTabToDel->nTabRef--;
    }
    pSubitem->pTab = 0;
  }

**
** If bFree is true, do not continue to use the pWith pointer after
** calling this routine,  Instead, use only the return value.
*/
SQLITE_PRIVATE With *sqlite3WithPush(Parse *pParse, With *pWith, u8 bFree){
  if( pWith ){
    if( bFree ){
      pWith = (With*)sqlite3ParserAddCleanup(pParse, sqlite3WithDeleteGeneric,

                      pWith);
      if( pWith==0 ) return 0;
    }
    if( pParse->nErr==0 ){
      assert( pParse->pWith!=pWith );
      pWith->pOuter = pParse->pWith;
      pParse->pWith = pWith;

*/
static void selectAddSubqueryTypeInfo(Walker *pWalker, Select *p){
  Parse *pParse;
  int i;
  SrcList *pTabList;
  SrcItem *pFrom;


  if( p->selFlags & SF_HasTypeInfo ) return;
  p->selFlags |= SF_HasTypeInfo;
  pParse = pWalker->pParse;
  testcase( (p->selFlags & SF_Resolved)==0 );
  assert( (p->selFlags & SF_Resolved) || IN_RENAME_OBJECT );
  pTabList = p->pSrc;
  for(i=0, pFrom=pTabList->a; i<pTabList->nSrc; i++, pFrom++){
    Table *pTab = pFrom->pTab;
    assert( pTab!=0 );
    if( (pTab->tabFlags & TF_Ephemeral)!=0 ){
      /* A sub-query in the FROM clause of a SELECT */
      Select *pSel = pFrom->pSelect;

    if( pFunc->iOBTab>=0 ){
      ExprList *pOBList;
      KeyInfo *pKeyInfo;
      int nExtra = 0;
      assert( pFunc->pFExpr->pLeft!=0 );
      assert( pFunc->pFExpr->pLeft->op==TK_ORDER );
      assert( ExprUseXList(pFunc->pFExpr->pLeft) );
      assert( pFunc->pFunc!=0 );
      pOBList = pFunc->pFExpr->pLeft->x.pList;
      if( !pFunc->bOBUnique ){
        nExtra++;  /* One extra column for the OP_Sequence */
      }
      if( pFunc->bOBPayload ){
        /* extra columns for the function arguments */
        assert( ExprUseXList(pFunc->pFExpr) );
        nExtra += pFunc->pFExpr->x.pList->nExpr;
      }
      if( pFunc->bUseSubtype ){
        nExtra += pFunc->pFExpr->x.pList->nExpr;
      }
      pKeyInfo = sqlite3KeyInfoFromExprList(pParse, pOBList, 0, nExtra);
      if( !pFunc->bOBUnique && pParse->nErr==0 ){
        pKeyInfo->nKeyField++;
      }
      sqlite3VdbeAddOp4(v, OP_OpenEphemeral,
            pFunc->iOBTab, pOBList->nExpr+nExtra, 0,
            (char*)pKeyInfo, P4_KEYINFO);

  int i;
  struct AggInfo_func *pF;
  for(i=0, pF=pAggInfo->aFunc; i<pAggInfo->nFunc; i++, pF++){
    ExprList *pList;
    assert( ExprUseXList(pF->pFExpr) );
    pList = pF->pFExpr->x.pList;
    if( pF->iOBTab>=0 ){
      /* For an ORDER BY aggregate, calls to OP_AggStep were deferred.  Inputs
      ** were stored in emphermal table pF->iOBTab.  Here, we extract those
      ** inputs (in ORDER BY order) and make all calls to OP_AggStep
      ** before doing the OP_AggFinal call. */
      int iTop;        /* Start of loop for extracting columns */
      int nArg;        /* Number of columns to extract */
      int nKey;        /* Key columns to be skipped */
      int regAgg;      /* Extract into this array */
      int j;           /* Loop counter */

      assert( pF->pFunc!=0 );
      nArg = pList->nExpr;
      regAgg = sqlite3GetTempRange(pParse, nArg);

      if( pF->bOBPayload==0 ){
        nKey = 0;
      }else{
        assert( pF->pFExpr->pLeft!=0 );
        assert( ExprUseXList(pF->pFExpr->pLeft) );
        assert( pF->pFExpr->pLeft->x.pList!=0 );
        nKey = pF->pFExpr->pLeft->x.pList->nExpr;
        if( ALWAYS(!pF->bOBUnique) ) nKey++;
      }
      iTop = sqlite3VdbeAddOp1(v, OP_Rewind, pF->iOBTab); VdbeCoverage(v);
      for(j=nArg-1; j>=0; j--){
        sqlite3VdbeAddOp3(v, OP_Column, pF->iOBTab, nKey+j, regAgg+j);
      }
      if( pF->bUseSubtype ){
        int regSubtype = sqlite3GetTempReg(pParse);
        int iBaseCol = nKey + nArg + (pF->bOBPayload==0 && pF->bOBUnique==0);
        for(j=nArg-1; j>=0; j--){
          sqlite3VdbeAddOp3(v, OP_Column, pF->iOBTab, iBaseCol+j, regSubtype);
          sqlite3VdbeAddOp2(v, OP_SetSubtype, regSubtype, regAgg+j);
        }
        sqlite3ReleaseTempReg(pParse, regSubtype);
      }
      sqlite3VdbeAddOp3(v, OP_AggStep, 0, regAgg, AggInfoFuncReg(pAggInfo,i));
      sqlite3VdbeAppendP4(v, pF->pFunc, P4_FUNCDEF);
      sqlite3VdbeChangeP5(v, (u8)nArg);
      sqlite3VdbeAddOp2(v, OP_Next, pF->iOBTab, iTop+1); VdbeCoverage(v);
      sqlite3VdbeJumpHere(v, iTop);
      sqlite3ReleaseTempRange(pParse, regAgg, nArg);
    }

** aggregate based on the current cursor position.
**
** If regAcc is non-zero and there are no min() or max() aggregates
** in pAggInfo, then only populate the pAggInfo->nAccumulator accumulator
** registers if register regAcc contains 0. The caller will take care
** of setting and clearing regAcc.
**
** For an ORDER BY aggregate, the actual accumulator memory cell update
** is deferred until after all input rows have been received, so that they
** can be run in the requested order.  In that case, instead of invoking
** OP_AggStep to update the accumulator, just add the arguments that would
** have been passed into OP_AggStep into the sorting ephemeral table
** (along with the appropriate sort key).
*/
static void updateAccumulator(
  Parse *pParse,
  int regAcc,
  AggInfo *pAggInfo,

  if( pParse->nErr ) return;
  pAggInfo->directMode = 1;
  for(i=0, pF=pAggInfo->aFunc; i<pAggInfo->nFunc; i++, pF++){
    int nArg;
    int addrNext = 0;
    int regAgg;
    int regAggSz = 0;
    int regDistinct = 0;
    ExprList *pList;
    assert( ExprUseXList(pF->pFExpr) );
    assert( !IsWindowFunc(pF->pFExpr) );
    assert( pF->pFunc!=0 );
    pList = pF->pFExpr->x.pList;
    if( ExprHasProperty(pF->pFExpr, EP_WinFunc) ){
      Expr *pFilter = pF->pFExpr->y.pWin->pFilter;
      if( pAggInfo->nAccumulator
       && (pF->pFunc->funcFlags & SQLITE_FUNC_NEEDCOLL)
       && regAcc
      ){

      assert( pOBList->nExpr>0 );
      regAggSz = pOBList->nExpr;
      if( !pF->bOBUnique ){
        regAggSz++;   /* One register for OP_Sequence */
      }
      if( pF->bOBPayload ){
        regAggSz += nArg;
      }
      if( pF->bUseSubtype ){
        regAggSz += nArg;
      }
      regAggSz++;  /* One extra register to hold result of MakeRecord */
      regAgg = sqlite3GetTempRange(pParse, regAggSz);
      regDistinct = regAgg;
      sqlite3ExprCodeExprList(pParse, pOBList, regAgg, 0, SQLITE_ECEL_DUP);
      jj = pOBList->nExpr;
      if( !pF->bOBUnique ){
        sqlite3VdbeAddOp2(v, OP_Sequence, pF->iOBTab, regAgg+jj);
        jj++;
      }
      if( pF->bOBPayload ){
        regDistinct = regAgg+jj;
        sqlite3ExprCodeExprList(pParse, pList, regDistinct, 0, SQLITE_ECEL_DUP);
        jj += nArg;
      }
      if( pF->bUseSubtype ){
        int kk;
        int regBase = pF->bOBPayload ? regDistinct : regAgg;
        for(kk=0; kk<nArg; kk++, jj++){
          sqlite3VdbeAddOp2(v, OP_GetSubtype, regBase+kk, regAgg+jj);
        }
      }
    }else if( pList ){
      nArg = pList->nExpr;
      regAgg = sqlite3GetTempRange(pParse, nArg);
      regDistinct = regAgg;
      sqlite3ExprCodeExprList(pParse, pList, regAgg, 0, SQLITE_ECEL_DUP);
    }else{
      nArg = 0;
      regAgg = 0;
    }
    if( pF->iDistinct>=0 && pList ){
      if( addrNext==0 ){
        addrNext = sqlite3VdbeMakeLabel(pParse);
      }
      pF->iDistinct = codeDistinct(pParse, eDistinctType,
          pF->iDistinct, addrNext, pList, regDistinct);
    }
    if( pF->iOBTab>=0 ){
      /* Insert a new record into the ORDER BY table */
      sqlite3VdbeAddOp3(v, OP_MakeRecord, regAgg, regAggSz-1,
                        regAgg+regAggSz-1);
      sqlite3VdbeAddOp4Int(v, OP_IdxInsert, pF->iOBTab, regAgg+regAggSz-1,
                           regAgg, regAggSz-1);

  }
  return 0;
}

/*
** Deallocate a single AggInfo object
*/
static void agginfoFree(sqlite3 *db, void *pArg){
  AggInfo *p = (AggInfo*)pArg;
  sqlite3DbFree(db, p->aCol);
  sqlite3DbFree(db, p->aFunc);
  sqlite3DbFreeNN(db, p);
}

/*
** Attempt to transform a query of the form

    Expr *pTerm;
    pPrior = pSub->pPrior;
    pSub->pPrior = 0;
    pSub->pNext = 0;
    pSub->selFlags |= SF_Aggregate;
    pSub->selFlags &= ~SF_Compound;
    pSub->nSelectRow = 0;
    sqlite3ParserAddCleanup(pParse, sqlite3ExprListDeleteGeneric, pSub->pEList);
    pTerm = pPrior ? sqlite3ExprDup(db, pCount, 0) : pCount;
    pSub->pEList = sqlite3ExprListAppend(pParse, 0, pTerm);
    pTerm = sqlite3PExpr(pParse, TK_SELECT, 0, 0);
    sqlite3PExprAddSelect(pParse, pTerm, pSub);
    if( pExpr==0 ){
      pExpr = pTerm;
    }else{

    if( p->pOrderBy ){
#if TREETRACE_ENABLED
      TREETRACE(0x800,pParse,p, ("dropping superfluous ORDER BY:\n"));
      if( sqlite3TreeTrace & 0x800 ){
        sqlite3TreeViewExprList(0, p->pOrderBy, 0, "ORDERBY");
      }
#endif
      sqlite3ParserAddCleanup(pParse, sqlite3ExprListDeleteGeneric,

                              p->pOrderBy);
      testcase( pParse->earlyCleanup );
      p->pOrderBy = 0;
    }
    p->selFlags &= ~SF_Distinct;
    p->selFlags |= SF_NoopOrderBy;
  }
  sqlite3SelectPrep(pParse, p, 0);

          TREETRACE(0x1000,pParse,p,
                    ("FULL-JOIN simplifies to RIGHT-JOIN on term %d\n",i));
          pItem->fg.jointype &= ~JT_LEFT;
        }else{
          TREETRACE(0x1000,pParse,p,
                    ("LEFT-JOIN simplifies to JOIN on term %d\n",i));
          pItem->fg.jointype &= ~(JT_LEFT|JT_OUTER);
          unsetJoinExpr(p->pWhere, pItem->iCursor, 0);
        }
      }
      if( pItem->fg.jointype & JT_LTORJ ){
        for(j=i+1; j<pTabList->nSrc; j++){
          SrcItem *pI2 = &pTabList->a[j];
          if( pI2->fg.jointype & JT_RIGHT ){
            if( pI2->fg.jointype & JT_LEFT ){
              TREETRACE(0x1000,pParse,p,
                        ("FULL-JOIN simplifies to LEFT-JOIN on term %d\n",j));
              pI2->fg.jointype &= ~JT_RIGHT;
            }else{
              TREETRACE(0x1000,pParse,p,
                        ("RIGHT-JOIN simplifies to JOIN on term %d\n",j));
              pI2->fg.jointype &= ~(JT_RIGHT|JT_OUTER);
              unsetJoinExpr(p->pWhere, pI2->iCursor, 1);
            }
          }
        }
        for(j=pTabList->nSrc-1; j>=0; j--){
          pTabList->a[j].fg.jointype &= ~JT_LTORJ;
          if( pTabList->a[j].fg.jointype & JT_RIGHT ) break;
        }
      }



    }

    /* No further action if this term of the FROM clause is not a subquery */
    if( pSub==0 ) continue;

    /* Catch mismatch in the declared columns of a view and the number of
    ** columns in the SELECT on the RHS */

     && pSub->pLimit==0                           /* Condition (1) */
     && (pSub->selFlags & SF_OrderByReqd)==0      /* Condition (2) */
     && (p->selFlags & SF_OrderByReqd)==0         /* Condition (3) and (4) */
     && OptimizationEnabled(db, SQLITE_OmitOrderBy)
    ){
      TREETRACE(0x800,pParse,p,
                ("omit superfluous ORDER BY on %r FROM-clause subquery\n",i+1));
      sqlite3ParserAddCleanup(pParse, sqlite3ExprListDeleteGeneric,

                              pSub->pOrderBy);
      pSub->pOrderBy = 0;
    }

    /* If the outer query contains a "complex" result set (that is,
    ** if the result set of the outer query uses functions or subqueries)
    ** and if the subquery contains an ORDER BY clause and if
    ** it will be implemented as a co-routine, then do not flatten.  This

    /* Convert TK_COLUMN nodes into TK_AGG_COLUMN and make entries in
    ** sAggInfo for all TK_AGG_FUNCTION nodes in expressions of the
    ** SELECT statement.
    */
    pAggInfo = sqlite3DbMallocZero(db, sizeof(*pAggInfo) );
    if( pAggInfo ){
      sqlite3ParserAddCleanup(pParse, agginfoFree, pAggInfo);

      testcase( pParse->earlyCleanup );
    }
    if( db->mallocFailed ){
      goto select_end;
    }
    pAggInfo->selId = p->selId;
#ifdef SQLITE_DEBUG

  sqlite3 *db = pParse->db;
  ExprList *pNew;
  Returning *pReturning;
  Select sSelect;
  SrcList sFrom;

  assert( v!=0 );
  if( !pParse->bReturning ){
    /* This RETURNING trigger must be for a different statement as
    ** this statement lacks a RETURNING clause. */
    return;
  }
  assert( db->pParse==pParse );
  pReturning = pParse->u1.pReturning;
  if( pTrigger != &(pReturning->retTrig) ){
    /* This RETURNING trigger is for a different statement */
    return;
  }
  memset(&sSelect, 0, sizeof(sSelect));
  memset(&sFrom, 0, sizeof(sFrom));
  sSelect.pEList = sqlite3ExprListDup(db, pReturning->pReturnEL, 0);
  sSelect.pSrc = &sFrom;
  sFrom.nSrc = 1;
  sFrom.a[0].pTab = pTab;
  sFrom.a[0].iCursor = -1;

  VTable *p = db->pDisconnect;

  assert( sqlite3BtreeHoldsAllMutexes(db) );
  assert( sqlite3_mutex_held(db->mutex) );

  if( p ){
    db->pDisconnect = 0;

    do {
      VTable *pNext = p->pNext;
      sqlite3VtabUnlock(p);
      p = pNext;
    }while( p );
  }
}

**
** where.c:
*/
SQLITE_PRIVATE Bitmask sqlite3WhereGetMask(WhereMaskSet*,int);
#ifdef WHERETRACE_ENABLED
SQLITE_PRIVATE void sqlite3WhereClausePrint(WhereClause *pWC);
SQLITE_PRIVATE void sqlite3WhereTermPrint(WhereTerm *pTerm, int iTerm);
SQLITE_PRIVATE void sqlite3WhereLoopPrint(const WhereLoop *p, const WhereClause *pWC);
#endif
SQLITE_PRIVATE WhereTerm *sqlite3WhereFindTerm(
  WhereClause *pWC,     /* The WHERE clause to be searched */
  int iCur,             /* Cursor number of LHS */
  int iColumn,          /* Column number of LHS */
  Bitmask notReady,     /* RHS must not overlap with this mask */
  u32 op,               /* Mask of WO_xx values describing operator */

  Vdbe *v = pParse->pVdbe;
  VdbeOp *pOp = sqlite3VdbeGetOp(v, iStart);
  int iEnd = sqlite3VdbeCurrentAddr(v);
  if( pParse->db->mallocFailed ) return;
  for(; iStart<iEnd; iStart++, pOp++){
    if( pOp->p1!=iTabCur ) continue;
    if( pOp->opcode==OP_Column ){
#ifdef SQLITE_DEBUG
      if( pParse->db->flags & SQLITE_VdbeAddopTrace ){
        printf("TRANSLATE OP_Column to OP_Copy at %d\n", iStart);
      }
#endif
      pOp->opcode = OP_Copy;
      pOp->p1 = pOp->p2 + iRegister;
      pOp->p2 = pOp->p3;
      pOp->p3 = 0;
      pOp->p5 = 2;  /* Cause the MEM_Subtype flag to be cleared */
    }else if( pOp->opcode==OP_Rowid ){
#ifdef SQLITE_DEBUG
      if( pParse->db->flags & SQLITE_VdbeAddopTrace ){
        printf("TRANSLATE OP_Rowid to OP_Sequence at %d\n", iStart);
      }
#endif
      pOp->opcode = OP_Sequence;
      pOp->p1 = iAutoidxCur;
#ifdef SQLITE_ALLOW_ROWID_IN_VIEW
      if( iAutoidxCur==0 ){
        pOp->opcode = OP_Null;
        pOp->p3 = 0;
      }

      if( rc==SQLITE_OK ){
        if( iUpper>iLower ){
          nNew = sqlite3LogEst(iUpper - iLower);
          /* TUNING:  If both iUpper and iLower are derived from the same
          ** sample, then assume they are 4x more selective.  This brings
          ** the estimated selectivity more in line with what it would be
          ** if estimated without the use of STAT4 tables. */
          if( iLwrIdx==iUprIdx ){ nNew -= 20; }
          assert( 20==sqlite3LogEst(4) );
        }else{
          nNew = 10;        assert( 10==sqlite3LogEst(2) );
        }
        if( nNew<nOut ){
          nOut = nNew;
        }
        WHERETRACE(0x20, ("STAT4 range scan: %u..%u  est=%d\n",

  }
}
#endif

#ifdef WHERETRACE_ENABLED
/*
** Print a WhereLoop object for debugging purposes
**
** Format example:
**
**     .--- Position in WHERE clause           rSetup, rRun, nOut ---.
**     |                                                             |
**     |  .--- selfMask                       nTerm ------.          |
**     |  |                                               |          |
**     |  |   .-- prereq    Idx          wsFlags----.     |          |
**     |  |   |             Name                    |     |          |
**     |  |   |           __|__        nEq ---.  ___|__   |        __|__
**     | / \ / \         /     \              | /      \ / \      /     \
**     1.002.001         t2.t2xy              2 f 010241 N 2 cost 0,56,31
*/
SQLITE_PRIVATE void sqlite3WhereLoopPrint(const WhereLoop *p, const WhereClause *pWC){
  if( pWC ){
    WhereInfo *pWInfo = pWC->pWInfo;
    int nb = 1+(pWInfo->pTabList->nSrc+3)/4;
    SrcItem *pItem = pWInfo->pTabList->a + p->iTab;
    Table *pTab = pItem->pTab;
    Bitmask mAll = (((Bitmask)1)<<(nb*4)) - 1;
    sqlite3DebugPrintf("%c%2d.%0*llx.%0*llx", p->cId,
                       p->iTab, nb, p->maskSelf, nb, p->prereq & mAll);
    sqlite3DebugPrintf(" %12s",
                       pItem->zAlias ? pItem->zAlias : pTab->zName);
  }else{
    sqlite3DebugPrintf("%c%2d.%03llx.%03llx %c%d",
         p->cId, p->iTab, p->maskSelf, p->prereq & 0xfff, p->cId, p->iTab);
  }
  if( (p->wsFlags & WHERE_VIRTUALTABLE)==0 ){
    const char *zName;
    if( p->u.btree.pIndex && (zName = p->u.btree.pIndex->zName)!=0 ){
      if( strncmp(zName, "sqlite_autoindex_", 17)==0 ){
        int i = sqlite3Strlen30(zName) - 1;
        while( zName[i]!='_' ) i--;
        zName += i;

  sqlite3DebugPrintf(" cost %d,%d,%d\n", p->rSetup, p->rRun, p->nOut);
  if( p->nLTerm && (sqlite3WhereTrace & 0x4000)!=0 ){
    int i;
    for(i=0; i<p->nLTerm; i++){
      sqlite3WhereTermPrint(p->aLTerm[i], i);
    }
  }
}
SQLITE_PRIVATE void sqlite3ShowWhereLoop(const WhereLoop *p){
  if( p ) sqlite3WhereLoopPrint(p, 0);
}
SQLITE_PRIVATE void sqlite3ShowWhereLoopList(const WhereLoop *p){
  while( p ){
    sqlite3ShowWhereLoop(p);
    p = p->pNextLoop;
  }
}
#endif

/*
** Convert bulk memory into a valid WhereLoop that can be passed
** to whereLoopClear harmlessly.
*/

    sqlite3DbNNFreeNN(db, pWInfo->pMemToFree);
    pWInfo->pMemToFree = pNext;
  }
  sqlite3DbNNFreeNN(db, pWInfo);
}

/*
** Return TRUE if X is a proper subset of Y but is of equal or less cost.
** In other words, return true if all constraints of X are also part of Y
** and Y has additional constraints that might speed the search that X lacks
** but the cost of running X is not more than the cost of running Y.
**
** In other words, return true if the cost relationwship between X and Y
** is inverted and needs to be adjusted.
**
** Case 1:
**
**   (1a)  X and Y use the same index.
**   (1b)  X has fewer == terms than Y
**   (1c)  Neither X nor Y use skip-scan
**   (1d)  X does not have a a greater cost than Y
**
** Case 2:
**
**   (2a)  X has the same or lower cost, or returns the same or fewer rows,
**         than Y.
**   (2b)  X uses fewer WHERE clause terms than Y
**   (2c)  Every WHERE clause term used by X is also used by Y
**   (2d)  X skips at least as many columns as Y
**   (2e)  If X is a covering index, than Y is too









*/
static int whereLoopCheaperProperSubset(
  const WhereLoop *pX,       /* First WhereLoop to compare */
  const WhereLoop *pY        /* Compare against this WhereLoop */
){
  int i, j;
  if( pX->rRun>pY->rRun && pX->nOut>pY->nOut ) return 0; /* (1d) and (2a) */
  assert( (pX->wsFlags & WHERE_VIRTUALTABLE)==0 );
  assert( (pY->wsFlags & WHERE_VIRTUALTABLE)==0 );
  if( pX->u.btree.nEq < pY->u.btree.nEq                  /* (1b) */
   && pX->u.btree.pIndex==pY->u.btree.pIndex             /* (1a) */
   && pX->nSkip==0 && pY->nSkip==0                       /* (1c) */
  ){
    return 1;  /* Case 1 is true */
  }
  if( pX->nLTerm-pX->nSkip >= pY->nLTerm-pY->nSkip ){
    return 0;                                            /* (2b) */
  }

  if( pY->nSkip > pX->nSkip ) return 0;                  /* (2d) */
  for(i=pX->nLTerm-1; i>=0; i--){
    if( pX->aLTerm[i]==0 ) continue;
    for(j=pY->nLTerm-1; j>=0; j--){
      if( pY->aLTerm[j]==pX->aLTerm[i] ) break;
    }
    if( j<0 ) return 0;                                  /* (2c) */
  }
  if( (pX->wsFlags&WHERE_IDX_ONLY)!=0
   && (pY->wsFlags&WHERE_IDX_ONLY)==0 ){
    return 0;                                            /* (2e) */
  }
  return 1;  /* Case 2 is true */
}

/*
** Try to adjust the cost and number of output rows of WhereLoop pTemplate
** upwards or downwards so that:
**
**   (1) pTemplate costs less than any other WhereLoops that are a proper

  assert( (pNew->wsFlags & WHERE_TOP_LIMIT)==0 );
  if( pNew->wsFlags & WHERE_BTM_LIMIT ){
    opMask = WO_LT|WO_LE;
  }else{
    assert( pNew->u.btree.nBtm==0 );
    opMask = WO_EQ|WO_IN|WO_GT|WO_GE|WO_LT|WO_LE|WO_ISNULL|WO_IS;
  }
  if( pProbe->bUnordered || pProbe->bLowQual ){
    if( pProbe->bUnordered ) opMask &= ~(WO_GT|WO_GE|WO_LT|WO_LE);
    if( pProbe->bLowQual )   opMask &= ~(WO_EQ|WO_IN|WO_IS);
  }

  assert( pNew->u.btree.nEq<pProbe->nColumn );
  assert( pNew->u.btree.nEq<pProbe->nKeyCol
       || pProbe->idxType!=SQLITE_IDXTYPE_PRIMARYKEY );

  saved_nEq = pNew->u.btree.nEq;
  saved_nBtm = pNew->u.btree.nBtm;

    }else if( j>=0 && (pTab->aCol[j].colFlags & COLFLAG_VIRTUAL)!=0 ){
      pExpr = sqlite3ColumnExpr(pTab, &pTab->aCol[j]);
      bMaybeNullRow = 0;
    }else{
      continue;
    }
    if( sqlite3ExprIsConstant(pExpr) ) continue;
    if( pExpr->op==TK_FUNCTION ){
      /* Functions that might set a subtype should not be replaced by the
      ** value taken from an expression index since the index omits the
      ** subtype.  https://sqlite.org/forum/forumpost/68d284c86b082c3e */
      int n;
      FuncDef *pDef;
      sqlite3 *db = pParse->db;
      assert( ExprUseXList(pExpr) );
      n = pExpr->x.pList ? pExpr->x.pList->nExpr : 0;
      pDef = sqlite3FindFunction(db, pExpr->u.zToken, n, ENC(db), 0);
      if( pDef==0 || (pDef->funcFlags & SQLITE_RESULT_SUBTYPE)!=0 ){
        continue;
      }
    }
    p = sqlite3DbMallocRaw(pParse->db,  sizeof(IndexedExpr));
    if( p==0 ) break;
    p->pIENext = pParse->pIdxEpr;
#ifdef WHERETRACE_ENABLED
    if( sqlite3WhereTrace & 0x200 ){
      sqlite3DebugPrintf("New pParse->pIdxEpr term {%d,%d}\n", iIdxCur, i);
      if( sqlite3WhereTrace & 0x5000 ) sqlite3ShowExpr(pExpr);

  /* Allocate and initialize the WhereInfo structure that will become the
  ** return value. A single allocation is used to store the WhereInfo
  ** struct, the contents of WhereInfo.a[], the WhereClause structure
  ** and the WhereMaskSet structure. Since WhereClause contains an 8-byte
  ** field (type Bitmask) it must be aligned on an 8-byte boundary on
  ** some architectures. Hence the ROUND8() below.
  */
  nByteWInfo = ROUND8P(sizeof(WhereInfo));
  if( nTabList>1 ){
    nByteWInfo = ROUND8P(nByteWInfo + (nTabList-1)*sizeof(WhereLevel));
  }
  pWInfo = sqlite3DbMallocRawNN(db, nByteWInfo + sizeof(WhereLoop));
  if( db->mallocFailed ){
    sqlite3DbFree(db, pWInfo);
    pWInfo = 0;
    goto whereBeginError;
  }
  pWInfo->pParse = pParse;

  /* Jump here if malloc fails */
whereBeginError:
  if( pWInfo ){
    pParse->nQueryLoop = pWInfo->savedNQueryLoop;
    whereInfoFree(db, pWInfo);
  }
#ifdef WHERETRACE_ENABLED
  /* Prevent harmless compiler warnings about debugging routines
  ** being declared but never used */
  sqlite3ShowWhereLoopList(0);
#endif /* WHERETRACE_ENABLED */
  return 0;
}

/*
** Part of sqlite3WhereEnd() will rewrite opcodes to reference the
** index rather than the main table.  In SQLITE_DEBUG mode, we want
** to trace those changes if PRAGMA vdbe_addoptrace=on.  This routine

    ** window function - one for the accumulator, another for interim
    ** results.  */
    for(pWin=pMWin; pWin; pWin=pWin->pNextWin){
      ExprList *pArgs;
      assert( ExprUseXList(pWin->pOwner) );
      assert( pWin->pWFunc!=0 );
      pArgs = pWin->pOwner->x.pList;
      if( pWin->pWFunc->funcFlags & SQLITE_SUBTYPE ){
        selectWindowRewriteEList(pParse, pMWin, pSrc, pArgs, pTab, &pSublist);
        pWin->iArgCol = (pSublist ? pSublist->nExpr : 0);
        pWin->bExprArgs = 1;
      }else{
        pWin->iArgCol = (pSublist ? pSublist->nExpr : 0);
        pSublist = exprListAppendList(pParse, pSublist, pArgs, 0);
      }

    int SQLITE_EXTRA_INIT(const char*);
    rc = SQLITE_EXTRA_INIT(0);
  }
#endif

  /* Experimentally determine if high-precision floating point is
  ** available. */
#ifndef SQLITE_OMIT_WSD
  sqlite3Config.bUseLongDouble = hasHighPrecisionDouble(rc);
#endif

  return rc;
}

/*
** Undo the effects of sqlite3_initialize().  Must not be called while
** there are outstanding database connections or memory allocations or

  ){
    return SQLITE_MISUSE_BKPT;
  }

  assert( SQLITE_FUNC_CONSTANT==SQLITE_DETERMINISTIC );
  assert( SQLITE_FUNC_DIRECT==SQLITE_DIRECTONLY );
  extraFlags = enc &  (SQLITE_DETERMINISTIC|SQLITE_DIRECTONLY|
                       SQLITE_SUBTYPE|SQLITE_INNOCUOUS|SQLITE_RESULT_SUBTYPE);
  enc &= (SQLITE_FUNC_ENCMASK|SQLITE_ANY);

  /* The SQLITE_INNOCUOUS flag is the same bit as SQLITE_FUNC_UNSAFE.  But
  ** the meaning is inverted.  So flip the bit. */
  assert( SQLITE_FUNC_UNSAFE==SQLITE_INNOCUOUS );
  extraFlags ^= SQLITE_FUNC_UNSAFE;  /* tag-20230109-1 */

        *piValue = Tuning(-id);
      }else{
        rc = SQLITE_NOTFOUND;
      }
      break;
    }
#endif

    /* sqlite3_test_control(SQLITE_TESTCTRL_JSON_SELFCHECK, &onOff);
    **
    ** Activate or deactivate validation of JSONB that is generated from
    ** text.  Off by default, as the validation is slow.  Validation is
    ** only available if compiled using SQLITE_DEBUG.
    **
    ** If onOff is initially 1, then turn it on.  If onOff is initially
    ** off, turn it off.  If onOff is initially -1, then change onOff
    ** to be the current setting.
    */
    case SQLITE_TESTCTRL_JSON_SELFCHECK: {
#if defined(SQLITE_DEBUG) && !defined(SQLITE_OMIT_WSD)
      int *pOnOff = va_arg(ap, int*);
      if( *pOnOff<0 ){
        *pOnOff = sqlite3Config.bJsonSelfcheck;
      }else{
        sqlite3Config.bJsonSelfcheck = (u8)((*pOnOff)&0xff);
      }
#endif
      break;
    }
  }
  va_end(ap);
#endif /* SQLITE_UNTESTABLE */
  return rc;
}

/*

  return 0;
}

/*
** Implementation of the xIntegrity() method on the FTS3/FTS4 virtual
** table.
*/
static int fts3Integrity(
  sqlite3_vtab *pVtab,      /* The virtual table to be checked */
  const char *zSchema,      /* Name of schema in which pVtab lives */
  const char *zTabname,     /* Name of the pVTab table */
  int isQuick,              /* True if this is a quick_check */
  char **pzErr              /* Write error message here */
){
  Fts3Table *p = (Fts3Table*)pVtab;
  char *zSql;
  int rc;
  char *zErr = 0;

  assert( pzErr!=0 );
  assert( *pzErr==0 );
  UNUSED_PARAMETER(isQuick);
  zSql = sqlite3_mprintf(
            "INSERT INTO \"%w\".\"%w\"(\"%w\") VALUES('integrity-check');",

            zSchema, zTabname, zTabname);
  if( zSql==0 ){
    return SQLITE_NOMEM;
  }
  rc = sqlite3_exec(p->db, zSql, 0, 0, &zErr);
  sqlite3_free(zSql);
  if( (rc&0xff)==SQLITE_CORRUPT ){
    *pzErr = sqlite3_mprintf("malformed inverted index for FTS%d table %s.%s",
                p->bFts4 ? 4 : 3, zSchema, zTabname);
  }else if( rc!=SQLITE_OK ){
    *pzErr = sqlite3_mprintf("unable to validate the inverted index for"
                             " FTS%d table %s.%s: %s",
                p->bFts4 ? 4 : 3, zSchema, zTabname, zErr);
  }
  sqlite3_free(zErr);
  return SQLITE_OK;
}

**
**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
******************************************************************************
**
** SQLite JSON functions.
**
** This file began as an extension in ext/misc/json1.c in 2015.  That
** extension proved so useful that it has now been moved into the core.
**
** The original design stored all JSON as pure text, canonical RFC-8259.
** Support for JSON-5 extensions was added with version 3.42.0 (2023-05-16).
** All generated JSON text still conforms strictly to RFC-8259, but text
** with JSON-5 extensions is accepted as input.
**
** Beginning with version 3.45.0 (circa 2024-01-01), these routines also
** accept BLOB values that have JSON encoded using a binary representation
** called "JSONB".  The name JSONB comes from PostgreSQL, however the on-disk
** format SQLite JSONB is completely different and incompatible with
** PostgreSQL JSONB.
**
** Decoding and interpreting JSONB is still O(N) where N is the size of
** the input, the same as text JSON.  However, the constant of proportionality
** for JSONB is much smaller due to faster parsing.  The size of each
** element in JSONB is encoded in its header, so there is no need to search
** for delimiters using persnickety syntax rules.  JSONB seems to be about
** 3x faster than text JSON as a result.  JSONB is also tends to be slightly
** smaller than text JSON, by 5% or 10%, but there are corner cases where
** JSONB can be slightly larger.  So you are not far mistaken to say that
** a JSONB blob is the same size as the equivalent RFC-8259 text.
**
**
** THE JSONB ENCODING:
**
** Every JSON element is encoded in JSONB as a header and a payload.
** The header is between 1 and 9 bytes in size.  The payload is zero
** or more bytes.
**
** The lower 4 bits of the first byte of the header determines the
** element type:
**
**    0:   NULL
**    1:   TRUE
**    2:   FALSE
**    3:   INT        -- RFC-8259 integer literal
**    4:   INT5       -- JSON5 integer literal
**    5:   FLOAT      -- RFC-8259 floating point literal
**    6:   FLOAT5     -- JSON5 floating point literal
**    7:   TEXT       -- Text literal acceptable to both SQL and JSON
**    8:   TEXTJ      -- Text containing RFC-8259 escapes
**    9:   TEXT5      -- Text containing JSON5 and/or RFC-8259 escapes
**   10:   TEXTRAW    -- Text containing unescaped syntax characters
**   11:   ARRAY
**   12:   OBJECT
**
** The other three possible values (13-15) are reserved for future
** enhancements.
**
** The upper 4 bits of the first byte determine the size of the header
** and sometimes also the size of the payload.  If X is the first byte
** of the element and if X>>4 is between 0 and 11, then the payload
** will be that many bytes in size and the header is exactly one byte
** in size.  Other four values for X>>4 (12-15) indicate that the header
** is more than one byte in size and that the payload size is determined
** by the remainder of the header, interpreted as a unsigned big-endian
** integer.
**
**   Value of X>>4         Size integer        Total header size
**   -------------     --------------------    -----------------
**        12           1 byte (0-255)                2
**        13           2 byte (0-65535)              3
**        14           4 byte (0-4294967295)         5
**        15           8 byte (0-1.8e19)             9
**
** The payload size need not be expressed in its minimal form.  For example,
** if the payload size is 10, the size can be expressed in any of 5 different
** ways: (1) (X>>4)==10, (2) (X>>4)==12 following by on 0x0a byte,
** (3) (X>>4)==13 followed by 0x00 and 0x0a, (4) (X>>4)==14 followed by
** 0x00 0x00 0x00 0x0a, or (5) (X>>4)==15 followed by 7 bytes of 0x00 and
** a single byte of 0x0a.  The shorter forms are preferred, of course, but
** sometimes when generating JSONB, the payload size is not known in advance
** and it is convenient to reserve sufficient header space to cover the
** largest possible payload size and then come back later and patch up
** the size when it becomes known, resulting in a non-minimal encoding.
**
** The value (X>>4)==15 is not actually used in the current implementation
** (as SQLite is currently unable handle BLOBs larger than about 2GB)
** but is included in the design to allow for future enhancements.
**
** The payload follows the header.  NULL, TRUE, and FALSE have no payload and
** their payload size must always be zero.  The payload for INT, INT5,
** FLOAT, FLOAT5, TEXT, TEXTJ, TEXT5, and TEXTROW is text.  Note that the
** "..." or '...' delimiters are omitted from the various text encodings.
** The payload for ARRAY and OBJECT is a list of additional elements that
** are the content for the array or object.  The payload for an OBJECT
** must be an even number of elements.  The first element of each pair is
** the label and must be of type TEXT, TEXTJ, TEXT5, or TEXTRAW.
**
** A valid JSONB blob consists of a single element, as described above.
** Usually this will be an ARRAY or OBJECT element which has many more
** elements as its content.  But the overall blob is just a single element.
**
** Input validation for JSONB blobs simply checks that the element type
** code is between 0 and 12 and that the total size of the element
** (header plus payload) is the same as the size of the BLOB.  If those
** checks are true, the BLOB is assumed to be JSONB and processing continues.
** Errors are only raised if some other miscoding is discovered during
** processing.
**
** Additional information can be found in the doc/jsonb.md file of the
** canonical SQLite source tree.
*/
#ifndef SQLITE_OMIT_JSON
/* #include "sqliteInt.h" */

/* JSONB element types
*/
#define JSONB_NULL     0   /* "null" */
#define JSONB_TRUE     1   /* "true" */
#define JSONB_FALSE    2   /* "false" */
#define JSONB_INT      3   /* integer acceptable to JSON and SQL */
#define JSONB_INT5     4   /* integer in 0x000 notation */
#define JSONB_FLOAT    5   /* float acceptable to JSON and SQL */
#define JSONB_FLOAT5   6   /* float with JSON5 extensions */
#define JSONB_TEXT     7   /* Text compatible with both JSON and SQL */
#define JSONB_TEXTJ    8   /* Text with JSON escapes */
#define JSONB_TEXT5    9   /* Text with JSON-5 escape */
#define JSONB_TEXTRAW 10   /* SQL text that needs escaping for JSON */
#define JSONB_ARRAY   11   /* An array */
#define JSONB_OBJECT  12   /* An object */

/* Human-readable names for the JSONB values.  The index for each
** string must correspond to the JSONB_* integer above.
*/
static const char * const jsonbType[] = {
  "null", "true", "false", "integer", "integer",
  "real", "real", "text",  "text",    "text",
  "text", "array", "object", "", "", "", ""
};

/*
** Growing our own isspace() routine this way is twice as fast as
** the library isspace() function, resulting in a 7% overall performance
** increase for the text-JSON parser.  (Ubuntu14.10 gcc 4.8.4 x64 with -Os).
*/
static const char jsonIsSpace[] = {
  0, 0, 0, 0, 0, 0, 0, 0,  0, 1, 1, 0, 0, 1, 0, 0,
  0, 0, 0, 0, 0, 0, 0, 0,  0, 0, 0, 0, 0, 0, 0, 0,
  1, 0, 0, 0, 0, 0, 0, 0,  0, 0, 0, 0, 0, 0, 0, 0,
  0, 0, 0, 0, 0, 0, 0, 0,  0, 0, 0, 0, 0, 0, 0, 0,
  0, 0, 0, 0, 0, 0, 0, 0,  0, 0, 0, 0, 0, 0, 0, 0,
  0, 0, 0, 0, 0, 0, 0, 0,  0, 0, 0, 0, 0, 0, 0, 0,
  0, 0, 0, 0, 0, 0, 0, 0,  0, 0, 0, 0, 0, 0, 0, 0,
  0, 0, 0, 0, 0, 0, 0, 0,  0, 0, 0, 0, 0, 0, 0, 0,

  0, 0, 0, 0, 0, 0, 0, 0,  0, 0, 0, 0, 0, 0, 0, 0,
  0, 0, 0, 0, 0, 0, 0, 0,  0, 0, 0, 0, 0, 0, 0, 0,
  0, 0, 0, 0, 0, 0, 0, 0,  0, 0, 0, 0, 0, 0, 0, 0,
  0, 0, 0, 0, 0, 0, 0, 0,  0, 0, 0, 0, 0, 0, 0, 0,
  0, 0, 0, 0, 0, 0, 0, 0,  0, 0, 0, 0, 0, 0, 0, 0,
  0, 0, 0, 0, 0, 0, 0, 0,  0, 0, 0, 0, 0, 0, 0, 0,
  0, 0, 0, 0, 0, 0, 0, 0,  0, 0, 0, 0, 0, 0, 0, 0,
  0, 0, 0, 0, 0, 0, 0, 0,  0, 0, 0, 0, 0, 0, 0, 0,
};
#define jsonIsspace(x) (jsonIsSpace[(unsigned char)x])

/*
** The set of all space characters recognized by jsonIsspace().
** Useful as the second argument to strspn().
*/
static const char jsonSpaces[] = "\011\012\015\040";

/*
** Characters that are special to JSON.  Control characters,
** '"' and '\\' and '\''.  Actually, '\'' is not special to
** canonical JSON, but it is special in JSON-5, so we include
** it in the set of special characters.
*/
static const char jsonIsOk[256] = {
  0, 0, 0, 0, 0, 0, 0, 0,  0, 0, 0, 0, 0, 0, 0, 0,
  0, 0, 0, 0, 0, 0, 0, 0,  0, 0, 0, 0, 0, 0, 0, 0,
  1, 1, 0, 1, 1, 1, 1, 0,  1, 1, 1, 1, 1, 1, 1, 1,
  1, 1, 1, 1, 1, 1, 1, 1,  1, 1, 1, 1, 1, 1, 1, 1,
  1, 1, 1, 1, 1, 1, 1, 1,  1, 1, 1, 1, 1, 1, 1, 1,

  1, 1, 1, 1, 1, 1, 1, 1,  1, 1, 1, 1, 1, 1, 1, 1,
  1, 1, 1, 1, 1, 1, 1, 1,  1, 1, 1, 1, 1, 1, 1, 1,
  1, 1, 1, 1, 1, 1, 1, 1,  1, 1, 1, 1, 1, 1, 1, 1,
  1, 1, 1, 1, 1, 1, 1, 1,  1, 1, 1, 1, 1, 1, 1, 1,
  1, 1, 1, 1, 1, 1, 1, 1,  1, 1, 1, 1, 1, 1, 1, 1
};








/* Objects */
typedef struct JsonCache JsonCache;
typedef struct JsonString JsonString;
typedef struct JsonParse JsonParse;

/*
** Magic number used for the JSON parse cache in sqlite3_get_auxdata()
*/
#define JSON_CACHE_ID    (-429938)  /* Cache entry */
#define JSON_CACHE_SIZE  4          /* Max number of cache entries */

/*
** jsonUnescapeOneChar() returns this invalid code point if it encounters
** a syntax error.
*/
#define JSON_INVALID_CHAR 0x99999

/* A cache mapping JSON text into JSONB blobs.
**
** Each cache entry is a JsonParse object with the following restrictions:
**
**    *   The bReadOnly flag must be set
**
**    *   The aBlob[] array must be owned by the JsonParse object.  In other
**        words, nBlobAlloc must be non-zero.
**
**    *   eEdit and delta must be zero.
**
**    *   zJson must be an RCStr.  In other words bJsonIsRCStr must be true.
*/
struct JsonCache {
  sqlite3 *db;                    /* Database connection */
  int nUsed;                      /* Number of active entries in the cache */
  JsonParse *a[JSON_CACHE_SIZE];  /* One line for each cache entry */
};

/* An instance of this object represents a JSON string
** under construction.  Really, this is a generic string accumulator
** that can be and is used to create strings other than JSON.
**
** If the generated string is longer than will fit into the zSpace[] buffer,
** then it will be an RCStr string.  This aids with caching of large
** JSON strings.
*/
struct JsonString {
  sqlite3_context *pCtx;   /* Function context - put error messages here */
  char *zBuf;              /* Append JSON content here */
  u64 nAlloc;              /* Bytes of storage available in zBuf[] */
  u64 nUsed;               /* Bytes of zBuf[] currently used */
  u8 bStatic;              /* True if zBuf is static space */
  u8 eErr;                 /* True if an error has been encountered */
  char zSpace[100];        /* Initial static space */
};









/* Allowed values for JsonString.eErr */



#define JSTRING_OOM         0x01   /* Out of memory */
#define JSTRING_MALFORMED   0x02   /* Malformed JSONB */
#define JSTRING_ERR         0x04   /* Error already sent to sqlite3_result */






/* The "subtype" set for text JSON values passed through using
** sqlite3_result_subtype() and sqlite3_value_subtype().
*/
#define JSON_SUBTYPE  74    /* Ascii for "J" */

/*






** Bit values for the flags passed into various SQL function implementations
** via the sqlite3_user_data() value.
*/


#define JSON_JSON      0x01        /* Result is always JSON */
#define JSON_SQL       0x02        /* Result is always SQL */

#define JSON_ABPATH    0x03        /* Allow abbreviated JSON path specs */
#define JSON_ISSET     0x04        /* json_set(), not json_insert() */
#define JSON_BLOB      0x08        /* Use the BLOB output format */























/* A parsed JSON value.  Lifecycle:

**
**   1.  JSON comes in and is parsed into a JSONB value in aBlob.  The
**       original text is stored in zJson.  This step is skipped if the
**       input is JSONB instead of text JSON.
**

**   2.  The aBlob[] array is searched using the JSON path notation, if needed.
**
**   3.  Zero or more changes are made to aBlob[] (via json_remove() or
**       json_replace() or json_patch() or similar).
**









**   4.  New JSON text is generated from the aBlob[] for output.  This step
**       is skipped if the function is one of the jsonb_* functions that
**       returns JSONB instead of text JSON.
*/
struct JsonParse {
  u8 *aBlob;         /* JSONB representation of JSON value */
  u32 nBlob;         /* Bytes of aBlob[] actually used */
  u32 nBlobAlloc;    /* Bytes allocated to aBlob[].  0 if aBlob is external */
  char *zJson;       /* Json text used for parsing */
  sqlite3 *db;       /* The database connection to which this object belongs */
  int nJson;         /* Length of the zJson string in bytes */
  u32 nJPRef;        /* Number of references to this object */
  u32 iErr;          /* Error location in zJson[] */
  u16 iDepth;        /* Nesting depth */
  u8 nErr;           /* Number of errors seen */
  u8 oom;            /* Set to true if out of memory */
  u8 bJsonIsRCStr;   /* True if zJson is an RCStr */
  u8 hasNonstd;      /* True if input uses non-standard features like JSON5 */
  u8 bReadOnly;      /* Do not modify. */
  /* Search and edit information.  See jsonLookupStep() */
  u8 eEdit;          /* Edit operation to apply */
  int delta;         /* Size change due to the edit */

  u32 nIns;          /* Number of bytes to insert */
  u32 iLabel;        /* Location of label if search landed on an object value */
  u8 *aIns;          /* Content to be inserted */
};

/* Allowed values for JsonParse.eEdit */
#define JEDIT_DEL   1   /* Delete if exists */
#define JEDIT_REPL  2   /* Overwrite if exists */
#define JEDIT_INS   3   /* Insert if not exists */
#define JEDIT_SET   4   /* Insert or overwrite */

/*
** Maximum nesting depth of JSON for this implementation.
**
** This limit is needed to avoid a stack overflow in the recursive
** descent parser.  A depth of 1000 is far deeper than any sane JSON
** should go.  Historical note: This limit was 2000 prior to version 3.42.0
*/
#ifndef SQLITE_JSON_MAX_DEPTH
# define JSON_MAX_DEPTH  1000
#else
# define JSON_MAX_DEPTH SQLITE_JSON_MAX_DEPTH
#endif

/*
** Allowed values for the flgs argument to jsonParseFuncArg();
*/
#define JSON_EDITABLE  0x01   /* Generate a writable JsonParse object */
#define JSON_KEEPERROR 0x02   /* Return non-NULL even if there is an error */

/**************************************************************************
** Forward references
**************************************************************************/
static void jsonReturnStringAsBlob(JsonString*);
static int jsonFuncArgMightBeBinary(sqlite3_value *pJson);
static u32 jsonTranslateBlobToText(const JsonParse*,u32,JsonString*);
static void jsonReturnParse(sqlite3_context*,JsonParse*);
static JsonParse *jsonParseFuncArg(sqlite3_context*,sqlite3_value*,u32);
static void jsonParseFree(JsonParse*);
static u32 jsonbPayloadSize(const JsonParse*, u32, u32*);
static u32 jsonUnescapeOneChar(const char*, u32, u32*);

/**************************************************************************
** Utility routines for dealing with JsonCache objects
**************************************************************************/

/*
** Free a JsonCache object.
*/
static void jsonCacheDelete(JsonCache *p){
  int i;
  for(i=0; i<p->nUsed; i++){
    jsonParseFree(p->a[i]);
  }
  sqlite3DbFree(p->db, p);
}
static void jsonCacheDeleteGeneric(void *p){
  jsonCacheDelete((JsonCache*)p);
}

/*
** Insert a new entry into the cache.  If the cache is full, expel
** the least recently used entry.  Return SQLITE_OK on success or a
** result code otherwise.
**
** Cache entries are stored in age order, oldest first.
*/
static int jsonCacheInsert(
  sqlite3_context *ctx,   /* The SQL statement context holding the cache */
  JsonParse *pParse       /* The parse object to be added to the cache */
){
  JsonCache *p;

  assert( pParse->zJson!=0 );
  assert( pParse->bJsonIsRCStr );
  assert( pParse->delta==0 );
  p = sqlite3_get_auxdata(ctx, JSON_CACHE_ID);
  if( p==0 ){
    sqlite3 *db = sqlite3_context_db_handle(ctx);
    p = sqlite3DbMallocZero(db, sizeof(*p));
    if( p==0 ) return SQLITE_NOMEM;
    p->db = db;
    sqlite3_set_auxdata(ctx, JSON_CACHE_ID, p, jsonCacheDeleteGeneric);
    p = sqlite3_get_auxdata(ctx, JSON_CACHE_ID);
    if( p==0 ) return SQLITE_NOMEM;
  }
  if( p->nUsed >= JSON_CACHE_SIZE ){
    jsonParseFree(p->a[0]);
    memmove(p->a, &p->a[1], (JSON_CACHE_SIZE-1)*sizeof(p->a[0]));
    p->nUsed = JSON_CACHE_SIZE-1;
  }
  assert( pParse->nBlobAlloc>0 );
  pParse->eEdit = 0;
  pParse->nJPRef++;
  pParse->bReadOnly = 1;
  p->a[p->nUsed] = pParse;
  p->nUsed++;
  return SQLITE_OK;
}

/*
** Search for a cached translation the json text supplied by pArg.  Return
** the JsonParse object if found.  Return NULL if not found.
**
** When a match if found, the matching entry is moved to become the
** most-recently used entry if it isn't so already.
**
** The JsonParse object returned still belongs to the Cache and might
** be deleted at any moment.  If the caller whants the JsonParse to
** linger, it needs to increment the nPJRef reference counter.
*/
static JsonParse *jsonCacheSearch(
  sqlite3_context *ctx,    /* The SQL statement context holding the cache */
  sqlite3_value *pArg      /* Function argument containing SQL text */
){
  JsonCache *p;
  int i;
  const char *zJson;
  int nJson;

  if( sqlite3_value_type(pArg)!=SQLITE_TEXT ){
    return 0;
  }
  zJson = (const char*)sqlite3_value_text(pArg);
  if( zJson==0 ) return 0;
  nJson = sqlite3_value_bytes(pArg);

  p = sqlite3_get_auxdata(ctx, JSON_CACHE_ID);
  if( p==0 ){
    return 0;
  }
  for(i=0; i<p->nUsed; i++){
    if( p->a[i]->zJson==zJson ) break;
  }
  if( i>=p->nUsed ){
    for(i=0; i<p->nUsed; i++){
      if( p->a[i]->nJson!=nJson ) continue;
      if( memcmp(p->a[i]->zJson, zJson, nJson)==0 ) break;
    }
  }
  if( i<p->nUsed ){
    if( i<p->nUsed-1 ){
      /* Make the matching entry the most recently used entry */
      JsonParse *tmp = p->a[i];
      memmove(&p->a[i], &p->a[i+1], (p->nUsed-i-1)*sizeof(tmp));
      p->a[p->nUsed-1] = tmp;
      i = p->nUsed - 1;
    }
    assert( p->a[i]->delta==0 );
    return p->a[i];
  }else{
    return 0;
  }
}

/**************************************************************************
** Utility routines for dealing with JsonString objects
**************************************************************************/

/* Turn uninitialized bulk memory into a valid JsonString object
** holding a zero-length string.
*/
static void jsonStringZero(JsonString *p){
  p->zBuf = p->zSpace;
  p->nAlloc = sizeof(p->zSpace);
  p->nUsed = 0;
  p->bStatic = 1;
}

/* Initialize the JsonString object
*/
static void jsonStringInit(JsonString *p, sqlite3_context *pCtx){
  p->pCtx = pCtx;
  p->eErr = 0;
  jsonStringZero(p);
}

/* Free all allocated memory and reset the JsonString object back to its
** initial state.
*/
static void jsonStringReset(JsonString *p){
  if( !p->bStatic ) sqlite3RCStrUnref(p->zBuf);
  jsonStringZero(p);
}

/* Report an out-of-memory (OOM) condition
*/
static void jsonStringOom(JsonString *p){
  p->eErr |= JSTRING_OOM;
  if( p->pCtx ) sqlite3_result_error_nomem(p->pCtx);
  jsonStringReset(p);
}

/* Enlarge pJson->zBuf so that it can hold at least N more bytes.
** Return zero on success.  Return non-zero on an OOM error
*/
static int jsonStringGrow(JsonString *p, u32 N){
  u64 nTotal = N<p->nAlloc ? p->nAlloc*2 : p->nAlloc+N+10;
  char *zNew;
  if( p->bStatic ){
    if( p->eErr ) return 1;
    zNew = sqlite3RCStrNew(nTotal);
    if( zNew==0 ){
      jsonStringOom(p);
      return SQLITE_NOMEM;
    }
    memcpy(zNew, p->zBuf, (size_t)p->nUsed);
    p->zBuf = zNew;
    p->bStatic = 0;
  }else{
    p->zBuf = sqlite3RCStrResize(p->zBuf, nTotal);
    if( p->zBuf==0 ){
      p->eErr |= JSTRING_OOM;
      jsonStringZero(p);
      return SQLITE_NOMEM;
    }
  }
  p->nAlloc = nTotal;
  return SQLITE_OK;
}

/* Append N bytes from zIn onto the end of the JsonString string.
*/
static SQLITE_NOINLINE void jsonStringExpandAndAppend(
  JsonString *p,
  const char *zIn,
  u32 N
){
  assert( N>0 );
  if( jsonStringGrow(p,N) ) return;
  memcpy(p->zBuf+p->nUsed, zIn, N);
  p->nUsed += N;
}
static void jsonAppendRaw(JsonString *p, const char *zIn, u32 N){
  if( N==0 ) return;
  if( N+p->nUsed >= p->nAlloc ){
    jsonStringExpandAndAppend(p,zIn,N);
  }else{
    memcpy(p->zBuf+p->nUsed, zIn, N);
    p->nUsed += N;
  }
}
static void jsonAppendRawNZ(JsonString *p, const char *zIn, u32 N){
  assert( N>0 );
  if( N+p->nUsed >= p->nAlloc ){
    jsonStringExpandAndAppend(p,zIn,N);
  }else{
    memcpy(p->zBuf+p->nUsed, zIn, N);
    p->nUsed += N;
  }
}


/* Append formatted text (not to exceed N bytes) to the JsonString.
*/
static void jsonPrintf(int N, JsonString *p, const char *zFormat, ...){
  va_list ap;
  if( (p->nUsed + N >= p->nAlloc) && jsonStringGrow(p, N) ) return;
  va_start(ap, zFormat);
  sqlite3_vsnprintf(N, p->zBuf+p->nUsed, zFormat, ap);
  va_end(ap);
  p->nUsed += (int)strlen(p->zBuf+p->nUsed);
}

/* Append a single character
*/
static SQLITE_NOINLINE void jsonAppendCharExpand(JsonString *p, char c){
  if( jsonStringGrow(p,1) ) return;
  p->zBuf[p->nUsed++] = c;
}
static void jsonAppendChar(JsonString *p, char c){
  if( p->nUsed>=p->nAlloc ){
    jsonAppendCharExpand(p,c);
  }else{
    p->zBuf[p->nUsed++] = c;
  }
}

/* Make sure there is a zero terminator on p->zBuf[]
**
** Return true on success.  Return false if an OOM prevents this
** from happening.
*/
static int jsonStringTerminate(JsonString *p){
  jsonAppendChar(p, 0);

  p->nUsed--;





  return p->eErr==0;
}


/* Append a comma separator to the output buffer, if the previous
** character is not '[' or '{'.
*/
static void jsonAppendSeparator(JsonString *p){
  char c;
  if( p->nUsed==0 ) return;
  c = p->zBuf[p->nUsed-1];
  if( c=='[' || c=='{' ) return;
  jsonAppendChar(p, ',');
}

/* Append the N-byte string in zIn to the end of the JsonString string
** under construction.  Enclose the string in double-quotes ("...") and
** escape any double-quotes or backslash characters contained within the
** string.
**
** This routine is a high-runner.  There is a measurable performance
** increase associated with unwinding the jsonIsOk[] loop.
*/
static void jsonAppendString(JsonString *p, const char *zIn, u32 N){
  u32 k;
  u8 c;
  const u8 *z = (const u8*)zIn;
  if( z==0 ) return;
  if( (N+p->nUsed+2 >= p->nAlloc) && jsonStringGrow(p,N+2)!=0 ) return;
  p->zBuf[p->nUsed++] = '"';

  while( 1 /*exit-by-break*/ ){
    k = 0;
    /* The following while() is the 4-way unwound equivalent of
    **
    **     while( k<N && jsonIsOk[z[k]] ){ k++; }
    */
    while( 1 /* Exit by break */ ){
      if( k+3>=N ){
        while( k<N && jsonIsOk[z[k]] ){ k++; }
        break;
      }
      if( !jsonIsOk[z[k]] ){
        break;
      }
      if( !jsonIsOk[z[k+1]] ){
        k += 1;
        break;
      }
      if( !jsonIsOk[z[k+2]] ){
        k += 2;
        break;
      }
      if( !jsonIsOk[z[k+3]] ){
        k += 3;
        break;
      }else{
        k += 4;
      }
    }
    if( k>=N ){
      if( k>0 ){
        memcpy(&p->zBuf[p->nUsed], z, k);
        p->nUsed += k;
      }
      break;
    }
    if( k>0 ){
      memcpy(&p->zBuf[p->nUsed], z, k);
      p->nUsed += k;
      z += k;
      N -= k;
    }
    c = z[0];
    if( c=='"' || c=='\\' ){
      json_simple_escape:
      if( (p->nUsed+N+3 > p->nAlloc) && jsonStringGrow(p,N+3)!=0 ) return;
      p->zBuf[p->nUsed++] = '\\';
      p->zBuf[p->nUsed++] = c;
    }else if( c=='\'' ){
      p->zBuf[p->nUsed++] = c;
    }else{
      static const char aSpecial[] = {
         0, 0, 0, 0, 0, 0, 0, 0, 'b', 't', 'n', 0, 'f', 'r', 0, 0,
         0, 0, 0, 0, 0, 0, 0, 0,   0,   0,   0, 0,   0,   0, 0, 0
      };
      assert( sizeof(aSpecial)==32 );
      assert( aSpecial['\b']=='b' );
      assert( aSpecial['\f']=='f' );
      assert( aSpecial['\n']=='n' );
      assert( aSpecial['\r']=='r' );
      assert( aSpecial['\t']=='t' );
      assert( c>=0 && c<sizeof(aSpecial) );
      if( aSpecial[c] ){
        c = aSpecial[c];
        goto json_simple_escape;
      }
      if( (p->nUsed+N+7 > p->nAlloc) && jsonStringGrow(p,N+7)!=0 ) return;
      p->zBuf[p->nUsed++] = '\\';
      p->zBuf[p->nUsed++] = 'u';
      p->zBuf[p->nUsed++] = '0';
      p->zBuf[p->nUsed++] = '0';
      p->zBuf[p->nUsed++] = "0123456789abcdef"[c>>4];
      p->zBuf[p->nUsed++] = "0123456789abcdef"[c&0xf];
    }
    z++;
    N--;
  }
  p->zBuf[p->nUsed++] = '"';
  assert( p->nUsed<p->nAlloc );
}

/*


























































** Append an sqlite3_value (such as a function parameter) to the JSON


































































** string under construction in p.
*/
static void jsonAppendSqlValue(
  JsonString *p,                 /* Append to this JSON string */
  sqlite3_value *pValue          /* Value to append */
){
  switch( sqlite3_value_type(pValue) ){
    case SQLITE_NULL: {
      jsonAppendRawNZ(p, "null", 4);
      break;

        jsonAppendRaw(p, z, n);
      }else{
        jsonAppendString(p, z, n);
      }
      break;
    }
    default: {
      if( jsonFuncArgMightBeBinary(pValue) ){
        JsonParse px;
        memset(&px, 0, sizeof(px));
        px.aBlob = (u8*)sqlite3_value_blob(pValue);
        px.nBlob = sqlite3_value_bytes(pValue);
        jsonTranslateBlobToText(&px, 0, p);
      }else if( p->eErr==0 ){
        sqlite3_result_error(p->pCtx, "JSON cannot hold BLOB values", -1);
        p->eErr = JSTRING_ERR;
        jsonStringReset(p);
      }
      break;
    }
  }
}

/* Make the text in p (which is probably a generated JSON text string)
** the result of the SQL function.
**
** The JsonString is reset.
**
** If pParse and ctx are both non-NULL, then the SQL string in p is
** loaded into the zJson field of the pParse object as a RCStr and the
** pParse is added to the cache.
*/
static void jsonReturnString(
  JsonString *p,            /* String to return */
  JsonParse *pParse,        /* JSONB source or NULL */
  sqlite3_context *ctx      /* Where to cache */
){
  assert( (pParse!=0)==(ctx!=0) );
  assert( ctx==0 || ctx==p->pCtx );
  if( p->eErr==0 ){
    int flags = SQLITE_PTR_TO_INT(sqlite3_user_data(p->pCtx));
    if( flags & JSON_BLOB ){
      jsonReturnStringAsBlob(p);
    }else if( p->bStatic ){
      sqlite3_result_text64(p->pCtx, p->zBuf, p->nUsed,
                            SQLITE_TRANSIENT, SQLITE_UTF8);
    }else if( jsonStringTerminate(p) ){
      if( pParse && pParse->bJsonIsRCStr==0 && pParse->nBlobAlloc>0 ){
        int rc;
        pParse->zJson = sqlite3RCStrRef(p->zBuf);
        pParse->nJson = p->nUsed;
        pParse->bJsonIsRCStr = 1;
        rc = jsonCacheInsert(ctx, pParse);
        if( rc==SQLITE_NOMEM ){
          sqlite3_result_error_nomem(ctx);
          jsonStringReset(p);
          return;
        }
      }
      sqlite3_result_text64(p->pCtx, sqlite3RCStrRef(p->zBuf), p->nUsed,
                            sqlite3RCStrUnref,
                            SQLITE_UTF8);
    }else{
      sqlite3_result_error_nomem(p->pCtx);
    }
  }else if( p->eErr & JSTRING_OOM ){
    sqlite3_result_error_nomem(p->pCtx);
  }else if( p->eErr & JSTRING_MALFORMED ){
    sqlite3_result_error(p->pCtx, "malformed JSON", -1);
  }
  jsonStringReset(p);
}

/**************************************************************************
** Utility routines for dealing with JsonParse objects
**************************************************************************/














/*
** Reclaim all memory allocated by a JsonParse object.  But do not
** delete the JsonParse object itself.
*/
static void jsonParseReset(JsonParse *pParse){






  assert( pParse->nJPRef<=1 );










  if( pParse->bJsonIsRCStr ){
    sqlite3RCStrUnref(pParse->zJson);
    pParse->zJson = 0;
    pParse->nJson = 0;
    pParse->bJsonIsRCStr = 0;
  }
  if( pParse->nBlobAlloc ){
    sqlite3DbFree(pParse->db, pParse->aBlob);
    pParse->aBlob = 0;
    pParse->nBlob = 0;
    pParse->nBlobAlloc = 0;
  }
}

/*
** Decrement the reference count on the JsonParse object.  When the
** count reaches zero, free the object.




*/
static void jsonParseFree(JsonParse *pParse){
  if( pParse ){
    if( pParse->nJPRef>1 ){
      pParse->nJPRef--;
    }else{
      jsonParseReset(pParse);
      sqlite3DbFree(pParse->db, pParse);
    }
  }
}


















































































































































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










** Utility routines for the JSON text parser














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

/*
** Translate a single byte of Hex into an integer.
** This routine only gives a correct answer if h really is a valid hexadecimal
** character:  0..9a..fA..F.  But unlike sqlite3HexToInt(), it does not
** assert() if the digit is not hex.
*/
static u8 jsonHexToInt(int h){

#ifdef SQLITE_ASCII
  h += 9*(1&(h>>6));
#endif
#ifdef SQLITE_EBCDIC
  h += 9*(1&~(h>>4));
#endif
  return (u8)(h & 0xf);
}

/*
** Convert a 4-byte hex string into an integer
*/
static u32 jsonHexToInt4(const char *z){
  u32 v;




  v = (jsonHexToInt(z[0])<<12)
    + (jsonHexToInt(z[1])<<8)
    + (jsonHexToInt(z[2])<<4)
    + jsonHexToInt(z[3]);
  return v;
}




















































































































































































































































































/*
** Return true if z[] begins with 2 (or more) hexadecimal digits
*/
static int jsonIs2Hex(const char *z){
  return sqlite3Isxdigit(z[0]) && sqlite3Isxdigit(z[1]);
}

  char c2;
  char n;
  char eType;
  char nRepl;
  char *zMatch;
  char *zRepl;
} aNanInfName[] = {
  { 'i', 'I', 3, JSONB_FLOAT, 7, "inf", "9.0e999" },
  { 'i', 'I', 8, JSONB_FLOAT, 7, "infinity", "9.0e999" },
  { 'n', 'N', 3, JSONB_NULL, 4, "NaN", "null" },
  { 'q', 'Q', 4, JSONB_NULL, 4, "QNaN", "null" },
  { 's', 'S', 4, JSONB_NULL, 4, "SNaN", "null" },
};


/*
** Report the wrong number of arguments for json_insert(), json_replace()
** or json_set().
*/
static void jsonWrongNumArgs(
  sqlite3_context *pCtx,
  const char *zFuncName
){
  char *zMsg = sqlite3_mprintf("json_%s() needs an odd number of arguments",
                               zFuncName);
  sqlite3_result_error(pCtx, zMsg, -1);
  sqlite3_free(zMsg);
}

/****************************************************************************
** Utility routines for dealing with the binary BLOB representation of JSON
****************************************************************************/

/*
** Expand pParse->aBlob so that it holds at least N bytes.
**
** Return the number of errors.
*/
static int jsonBlobExpand(JsonParse *pParse, u32 N){
  u8 *aNew;
  u32 t;
  assert( N>pParse->nBlobAlloc );
  if( pParse->nBlobAlloc==0 ){
    t = 100;
  }else{
    t = pParse->nBlobAlloc*2;
  }
  if( t<N ) t = N+100;
  aNew = sqlite3DbRealloc(pParse->db, pParse->aBlob, t);
  if( aNew==0 ){ pParse->oom = 1; return 1; }
  pParse->aBlob = aNew;
  pParse->nBlobAlloc = t;
  return 0;
}

/*
** If pParse->aBlob is not previously editable (because it is taken
** from sqlite3_value_blob(), as indicated by the fact that
** pParse->nBlobAlloc==0 and pParse->nBlob>0) then make it editable
** by making a copy into space obtained from malloc.
**
** Return true on success.  Return false on OOM.
*/
static int jsonBlobMakeEditable(JsonParse *pParse, u32 nExtra){
  u8 *aOld;
  u32 nSize;
  assert( !pParse->bReadOnly );
  if( pParse->oom ) return 0;
  if( pParse->nBlobAlloc>0 ) return 1;
  aOld = pParse->aBlob;
  nSize = pParse->nBlob + nExtra;
  pParse->aBlob = 0;
  if( jsonBlobExpand(pParse, nSize) ){
    return 0;
  }
  assert( pParse->nBlobAlloc >= pParse->nBlob + nExtra );
  memcpy(pParse->aBlob, aOld, pParse->nBlob);
  return 1;
}

/* Expand pParse->aBlob and append one bytes.
*/
static SQLITE_NOINLINE void jsonBlobExpandAndAppendOneByte(
  JsonParse *pParse,
  u8 c
){
  jsonBlobExpand(pParse, pParse->nBlob+1);
  if( pParse->oom==0 ){
    assert( pParse->nBlob+1<=pParse->nBlobAlloc );
    pParse->aBlob[pParse->nBlob++] = c;
  }
}

/* Append a single character.
*/
static void jsonBlobAppendOneByte(JsonParse *pParse, u8 c){
  if( pParse->nBlob >= pParse->nBlobAlloc ){
    jsonBlobExpandAndAppendOneByte(pParse, c);
  }else{
    pParse->aBlob[pParse->nBlob++] = c;
  }
}

/* Slow version of jsonBlobAppendNode() that first resizes the
** pParse->aBlob structure.
*/
static void jsonBlobAppendNode(JsonParse*,u8,u32,const void*);
static SQLITE_NOINLINE void jsonBlobExpandAndAppendNode(
  JsonParse *pParse,
  u8 eType,
  u32 szPayload,
  const void *aPayload
){
  if( jsonBlobExpand(pParse, pParse->nBlob+szPayload+9) ) return;
  jsonBlobAppendNode(pParse, eType, szPayload, aPayload);
}


/* Append an node type byte together with the payload size and
** possibly also the payload.
**
** If aPayload is not NULL, then it is a pointer to the payload which
** is also appended.  If aPayload is NULL, the pParse->aBlob[] array
** is resized (if necessary) so that it is big enough to hold the
** payload, but the payload is not appended and pParse->nBlob is left
** pointing to where the first byte of payload will eventually be.
*/
static void jsonBlobAppendNode(
  JsonParse *pParse,          /* The JsonParse object under construction */
  u8 eType,                   /* Node type.  One of JSONB_* */
  u32 szPayload,              /* Number of bytes of payload */
  const void *aPayload        /* The payload.  Might be NULL */
){
  u8 *a;
  if( pParse->nBlob+szPayload+9 > pParse->nBlobAlloc ){
    jsonBlobExpandAndAppendNode(pParse,eType,szPayload,aPayload);
    return;
  }
  assert( pParse->aBlob!=0 );
  a = &pParse->aBlob[pParse->nBlob];
  if( szPayload<=11 ){
    a[0] = eType | (szPayload<<4);
    pParse->nBlob += 1;
  }else if( szPayload<=0xff ){
    a[0] = eType | 0xc0;
    a[1] = szPayload & 0xff;
    pParse->nBlob += 2;
  }else if( szPayload<=0xffff ){
    a[0] = eType | 0xd0;
    a[1] = (szPayload >> 8) & 0xff;
    a[2] = szPayload & 0xff;
    pParse->nBlob += 3;
  }else{
    a[0] = eType | 0xe0;
    a[1] = (szPayload >> 24) & 0xff;
    a[2] = (szPayload >> 16) & 0xff;
    a[3] = (szPayload >> 8) & 0xff;
    a[4] = szPayload & 0xff;
    pParse->nBlob += 5;
  }
  if( aPayload ){
    pParse->nBlob += szPayload;
    memcpy(&pParse->aBlob[pParse->nBlob-szPayload], aPayload, szPayload);
  }
}

/* Change the payload size for the node at index i to be szPayload.
*/
static int jsonBlobChangePayloadSize(
  JsonParse *pParse,
  u32 i,
  u32 szPayload
){
  u8 *a;
  u8 szType;
  u8 nExtra;
  u8 nNeeded;
  int delta;
  if( pParse->oom ) return 0;
  a = &pParse->aBlob[i];
  szType = a[0]>>4;
  if( szType<=11 ){
    nExtra = 0;
  }else if( szType==12 ){
    nExtra = 1;
  }else if( szType==13 ){
    nExtra = 2;
  }else{
    nExtra = 4;
  }
  if( szPayload<=11 ){
    nNeeded = 0;
  }else if( szPayload<=0xff ){
    nNeeded = 1;
  }else if( szPayload<=0xffff ){
    nNeeded = 2;
  }else{
    nNeeded = 4;
  }
  delta = nNeeded - nExtra;
  if( delta ){
    u32 newSize = pParse->nBlob + delta;
    if( delta>0 ){
      if( newSize>pParse->nBlobAlloc && jsonBlobExpand(pParse, newSize) ){
        return 0;  /* OOM error.  Error state recorded in pParse->oom. */
      }
      a = &pParse->aBlob[i];
      memmove(&a[1+delta], &a[1], pParse->nBlob - (i+1));
    }else{
      memmove(&a[1], &a[1-delta], pParse->nBlob - (i+1-delta));
    }
    pParse->nBlob = newSize;
  }
  if( nNeeded==0 ){
    a[0] = (a[0] & 0x0f) | (szPayload<<4);
  }else if( nNeeded==1 ){
    a[0] = (a[0] & 0x0f) | 0xc0;
    a[1] = szPayload & 0xff;
  }else if( nNeeded==2 ){
    a[0] = (a[0] & 0x0f) | 0xd0;
    a[1] = (szPayload >> 8) & 0xff;
    a[2] = szPayload & 0xff;
  }else{
    a[0] = (a[0] & 0x0f) | 0xe0;
    a[1] = (szPayload >> 24) & 0xff;
    a[2] = (szPayload >> 16) & 0xff;
    a[3] = (szPayload >> 8) & 0xff;
    a[4] = szPayload & 0xff;
  }
  return delta;
}

/*
** If z[0] is 'u' and is followed by exactly 4 hexadecimal character,
** then set *pOp to JSONB_TEXTJ and return true.  If not, do not make
** any changes to *pOp and return false.
*/
static int jsonIs4HexB(const char *z, int *pOp){
  if( z[0]!='u' ) return 0;
  if( !jsonIs4Hex(&z[1]) ) return 0;
  *pOp = JSONB_TEXTJ;
  return 1;
}

/*
** Check a single element of the JSONB in pParse for validity.
**
** The element to be checked starts at offset i and must end at on the
** last byte before iEnd.
**
** Return 0 if everything is correct.  Return the 1-based byte offset of the
** error if a problem is detected.  (In other words, if the error is at offset
** 0, return 1).
*/
static u32 jsonbValidityCheck(
  const JsonParse *pParse,    /* Input JSONB.  Only aBlob and nBlob are used */
  u32 i,                      /* Start of element as pParse->aBlob[i] */
  u32 iEnd,                   /* One more than the last byte of the element */
  u32 iDepth                  /* Current nesting depth */
){
  u32 n, sz, j, k;
  const u8 *z;
  u8 x;
  if( iDepth>JSON_MAX_DEPTH ) return i+1;
  sz = 0;
  n = jsonbPayloadSize(pParse, i, &sz);
  if( NEVER(n==0) ) return i+1;          /* Checked by caller */
  if( NEVER(i+n+sz!=iEnd) ) return i+1;  /* Checked by caller */
  z = pParse->aBlob;
  x = z[i] & 0x0f;
  switch( x ){
    case JSONB_NULL:
    case JSONB_TRUE:
    case JSONB_FALSE: {
      return n+sz==1 ? 0 : i+1;
    }
    case JSONB_INT: {
      if( sz<1 ) return i+1;
      j = i+n;
      if( z[j]=='-' ){
        j++;
        if( sz<2 ) return i+1;
      }
      k = i+n+sz;
      while( j<k ){
        if( sqlite3Isdigit(z[j]) ){
          j++;
        }else{
          return j+1;
        }
      }
      return 0;
    }
    case JSONB_INT5: {
      if( sz<3 ) return i+1;
      j = i+n;
      if( z[j]=='-' ){
        if( sz<4 ) return i+1;
        j++;
      }
      if( z[j]!='0' ) return i+1;
      if( z[j+1]!='x' && z[j+1]!='X' ) return j+2;
      j += 2;
      k = i+n+sz;
      while( j<k ){
        if( sqlite3Isxdigit(z[j]) ){
          j++;
        }else{
          return j+1;
        }
      }
      return 0;
    }
    case JSONB_FLOAT:
    case JSONB_FLOAT5: {
      u8 seen = 0;   /* 0: initial.  1: '.' seen  2: 'e' seen */
      if( sz<2 ) return i+1;
      j = i+n;
      k = j+sz;
      if( z[j]=='-' ){
        j++;
        if( sz<3 ) return i+1;
      }
      if( z[j]=='.' ){
        if( x==JSONB_FLOAT ) return j+1;
        if( !sqlite3Isdigit(z[j+1]) ) return j+1;
        j += 2;
        seen = 1;
      }else if( z[j]=='0' && x==JSONB_FLOAT ){
        if( j+3>k ) return j+1;
        if( z[j+1]!='.' && z[j+1]!='e' && z[j+1]!='E' ) return j+1;
        j++;
      }
      for(; j<k; j++){
        if( sqlite3Isdigit(z[j]) ) continue;
        if( z[j]=='.' ){
          if( seen>0 ) return j+1;
          if( x==JSONB_FLOAT && (j==k-1 || !sqlite3Isdigit(z[j+1])) ){
            return j+1;
          }
          seen = 1;
          continue;
        }
        if( z[j]=='e' || z[j]=='E' ){
          if( seen==2 ) return j+1;
          if( j==k-1 ) return j+1;
          if( z[j+1]=='+' || z[j+1]=='-' ){
            j++;
            if( j==k-1 ) return j+1;
          }
          seen = 2;
          continue;
        }
        return j+1;
      }
      if( seen==0 ) return i+1;
      return 0;
    }
    case JSONB_TEXT: {
      j = i+n;
      k = j+sz;
      while( j<k ){
        if( !jsonIsOk[z[j]] && z[j]!='\'' ) return j+1;
        j++;
      }
      return 0;
    }
    case JSONB_TEXTJ:
    case JSONB_TEXT5: {
      j = i+n;
      k = j+sz;
      while( j<k ){
        if( !jsonIsOk[z[j]] && z[j]!='\'' ){
          if( z[j]=='"' ){
            if( x==JSONB_TEXTJ ) return j+1;
          }else if( z[j]!='\\' || j+1>=k ){
            return j+1;
          }else if( strchr("\"\\/bfnrt",z[j+1])!=0 ){
            j++;
          }else if( z[j+1]=='u' ){
            if( j+5>=k ) return j+1;
            if( !jsonIs4Hex((const char*)&z[j+2]) ) return j+1;
            j++;
          }else if( x!=JSONB_TEXT5 ){
            return j+1;
          }else{
            u32 c = 0;
            u32 szC = jsonUnescapeOneChar((const char*)&z[j], k-j, &c);
            if( c==JSON_INVALID_CHAR ) return j+1;
            j += szC - 1;
          }
        }
        j++;
      }
      return 0;
    }
    case JSONB_TEXTRAW: {
      return 0;
    }
    case JSONB_ARRAY: {
      u32 sub;
      j = i+n;
      k = j+sz;
      while( j<k ){
        sz = 0;
        n = jsonbPayloadSize(pParse, j, &sz);
        if( n==0 ) return j+1;
        if( j+n+sz>k ) return j+1;
        sub = jsonbValidityCheck(pParse, j, j+n+sz, iDepth+1);
        if( sub ) return sub;
        j += n + sz;
      }
      assert( j==k );
      return 0;
    }
    case JSONB_OBJECT: {
      u32 cnt = 0;
      u32 sub;
      j = i+n;
      k = j+sz;
      while( j<k ){
        sz = 0;
        n = jsonbPayloadSize(pParse, j, &sz);
        if( n==0 ) return j+1;
        if( j+n+sz>k ) return j+1;
        if( (cnt & 1)==0 ){
          x = z[j] & 0x0f;
          if( x<JSONB_TEXT || x>JSONB_TEXTRAW ) return j+1;
        }
        sub = jsonbValidityCheck(pParse, j, j+n+sz, iDepth+1);
        if( sub ) return sub;
        cnt++;
        j += n + sz;
      }
      assert( j==k );
      if( (cnt & 1)!=0 ) return j+1;
      return 0;
    }
    default: {
      return i+1;
    }
  }
}

/*
** Translate a single element of JSON text at pParse->zJson[i] into

** its equivalent binary JSONB representation.  Append the translation into
** pParse->aBlob[] beginning at pParse->nBlob.  The size of
** pParse->aBlob[] is increased as necessary.
**
** Return the index of the first character past the end of the element parsed,
** or one of the following special result codes:
**
**      0    End of input
**     -1    Syntax error or OOM
**     -2    '}' seen   \
**     -3    ']' seen    \___  For these returns, pParse->iErr is set to
**     -4    ',' seen    /     the index in zJson[] of the seen character
**     -5    ':' seen   /
*/
static int jsonTranslateTextToBlob(JsonParse *pParse, u32 i){
  char c;
  u32 j;
  u32 iThis, iStart;
  int x;
  u8 t;
  const char *z = pParse->zJson;
json_parse_restart:
  switch( (u8)z[i] ){
  case '{': {
    /* Parse object */
    iThis = pParse->nBlob;
    jsonBlobAppendNode(pParse, JSONB_OBJECT, pParse->nJson-i, 0);

    if( ++pParse->iDepth > JSON_MAX_DEPTH ){
      pParse->iErr = i;
      return -1;
    }
    iStart = pParse->nBlob;
    for(j=i+1;;j++){
      u32 iBlob = pParse->nBlob;
      x = jsonTranslateTextToBlob(pParse, j);
      if( x<=0 ){
        int op;
        if( x==(-2) ){
          j = pParse->iErr;
          if( pParse->nBlob!=(u32)iStart ) pParse->hasNonstd = 1;
          break;
        }
        j += json5Whitespace(&z[j]);
        op = JSONB_TEXT;
        if( sqlite3JsonId1(z[j])
         || (z[j]=='\\' && jsonIs4HexB(&z[j+1], &op))
        ){
          int k = j+1;
          while( (sqlite3JsonId2(z[k]) && json5Whitespace(&z[k])==0)
            || (z[k]=='\\' && jsonIs4HexB(&z[k+1], &op))
          ){
            k++;
          }
          assert( iBlob==pParse->nBlob );
          jsonBlobAppendNode(pParse, op, k-j, &z[j]);
          pParse->hasNonstd = 1;
          x = k;
        }else{
          if( x!=-1 ) pParse->iErr = j;
          return -1;
        }
      }
      if( pParse->oom ) return -1;
      t = pParse->aBlob[iBlob] & 0x0f;
      if( t<JSONB_TEXT || t>JSONB_TEXTRAW ){
        pParse->iErr = j;
        return -1;
      }

      j = x;
      if( z[j]==':' ){
        j++;
      }else{
        if( jsonIsspace(z[j]) ){
          /* strspn() is not helpful here */
          do{ j++; }while( jsonIsspace(z[j]) );
          if( z[j]==':' ){
            j++;
            goto parse_object_value;
          }
        }
        x = jsonTranslateTextToBlob(pParse, j);
        if( x!=(-5) ){
          if( x!=(-1) ) pParse->iErr = j;
          return -1;
        }
        j = pParse->iErr+1;
      }
    parse_object_value:
      x = jsonTranslateTextToBlob(pParse, j);
      if( x<=0 ){
        if( x!=(-1) ) pParse->iErr = j;
        return -1;
      }
      j = x;
      if( z[j]==',' ){
        continue;
      }else if( z[j]=='}' ){
        break;
      }else{
        if( jsonIsspace(z[j]) ){
          j += 1 + (u32)strspn(&z[j+1], jsonSpaces);
          if( z[j]==',' ){
            continue;
          }else if( z[j]=='}' ){
            break;
          }
        }
        x = jsonTranslateTextToBlob(pParse, j);
        if( x==(-4) ){
          j = pParse->iErr;
          continue;
        }
        if( x==(-2) ){
          j = pParse->iErr;
          break;
        }
      }
      pParse->iErr = j;
      return -1;
    }
    jsonBlobChangePayloadSize(pParse, iThis, pParse->nBlob - iStart);
    pParse->iDepth--;
    return j+1;
  }
  case '[': {
    /* Parse array */
    iThis = pParse->nBlob;
    jsonBlobAppendNode(pParse, JSONB_ARRAY, pParse->nJson - i, 0);
    iStart = pParse->nBlob;
    if( pParse->oom ) return -1;
    if( ++pParse->iDepth > JSON_MAX_DEPTH ){
      pParse->iErr = i;
      return -1;
    }

    for(j=i+1;;j++){
      x = jsonTranslateTextToBlob(pParse, j);
      if( x<=0 ){
        if( x==(-3) ){
          j = pParse->iErr;
          if( pParse->nBlob!=iStart ) pParse->hasNonstd = 1;
          break;
        }
        if( x!=(-1) ) pParse->iErr = j;
        return -1;
      }
      j = x;
      if( z[j]==',' ){
        continue;
      }else if( z[j]==']' ){
        break;
      }else{
        if( jsonIsspace(z[j]) ){
          j += 1 + (u32)strspn(&z[j+1], jsonSpaces);
          if( z[j]==',' ){
            continue;
          }else if( z[j]==']' ){
            break;
          }
        }
        x = jsonTranslateTextToBlob(pParse, j);
        if( x==(-4) ){
          j = pParse->iErr;
          continue;
        }
        if( x==(-3) ){
          j = pParse->iErr;
          break;
        }
      }
      pParse->iErr = j;
      return -1;
    }
    jsonBlobChangePayloadSize(pParse, iThis, pParse->nBlob - iStart);
    pParse->iDepth--;
    return j+1;
  }
  case '\'': {
    u8 opcode;
    char cDelim;
    pParse->hasNonstd = 1;
    opcode = JSONB_TEXT;
    goto parse_string;
  case '"':
    /* Parse string */
    opcode = JSONB_TEXT;
  parse_string:
    cDelim = z[i];
    j = i+1;
    while( 1 /*exit-by-break*/ ){
      if( jsonIsOk[(u8)z[j]] ){
        if( !jsonIsOk[(u8)z[j+1]] ){
          j += 1;
        }else if( !jsonIsOk[(u8)z[j+2]] ){
          j += 2;
        }else{
          j += 3;
          continue;
        }
      }
      c = z[j];
      if( c==cDelim ){
        break;
      }else if( c=='\\' ){
        c = z[++j];
        if( c=='"' || c=='\\' || c=='/' || c=='b' || c=='f'
           || c=='n' || c=='r' || c=='t'
           || (c=='u' && jsonIs4Hex(&z[j+1])) ){
          if( opcode==JSONB_TEXT ) opcode = JSONB_TEXTJ;
        }else if( c=='\'' || c=='0' || c=='v' || c=='\n'
           || (0xe2==(u8)c && 0x80==(u8)z[j+1]
                && (0xa8==(u8)z[j+2] || 0xa9==(u8)z[j+2]))
           || (c=='x' && jsonIs2Hex(&z[j+1])) ){
          opcode = JSONB_TEXT5;
          pParse->hasNonstd = 1;
        }else if( c=='\r' ){
          if( z[j+1]=='\n' ) j++;
          opcode = JSONB_TEXT5;
          pParse->hasNonstd = 1;
        }else{
          pParse->iErr = j;
          return -1;
        }
      }else if( c<=0x1f ){
        /* Control characters are not allowed in strings */
        pParse->iErr = j;
        return -1;
      }else if( c=='"' ){
        opcode = JSONB_TEXT5;
      }
      j++;
    }
    jsonBlobAppendNode(pParse, opcode, j-1-i, &z[i+1]);
    return j+1;
  }
  case 't': {
    if( strncmp(z+i,"true",4)==0 && !sqlite3Isalnum(z[i+4]) ){
      jsonBlobAppendOneByte(pParse, JSONB_TRUE);
      return i+4;
    }
    pParse->iErr = i;
    return -1;
  }
  case 'f': {
    if( strncmp(z+i,"false",5)==0 && !sqlite3Isalnum(z[i+5]) ){
      jsonBlobAppendOneByte(pParse, JSONB_FALSE);
      return i+5;
    }
    pParse->iErr = i;
    return -1;
  }
  case '+': {
    u8 seenE;
    pParse->hasNonstd = 1;
    t = 0x00;            /* Bit 0x01:  JSON5.   Bit 0x02:  FLOAT */
    goto parse_number;
  case '.':
    if( sqlite3Isdigit(z[i+1]) ){
      pParse->hasNonstd = 1;
      t = 0x03;          /* Bit 0x01:  JSON5.   Bit 0x02:  FLOAT */
      seenE = 0;

      goto parse_number_2;
    }
    pParse->iErr = i;
    return -1;
  case '-':
  case '0':
  case '1':
  case '2':
  case '3':
  case '4':
  case '5':
  case '6':
  case '7':
  case '8':
  case '9':
    /* Parse number */
    t = 0x00;            /* Bit 0x01:  JSON5.   Bit 0x02:  FLOAT */
  parse_number:

    seenE = 0;
    assert( '-' < '0' );
    assert( '+' < '0' );
    assert( '.' < '0' );
    c = z[i];

    if( c<='0' ){
      if( c=='0' ){
        if( (z[i+1]=='x' || z[i+1]=='X') && sqlite3Isxdigit(z[i+2]) ){
          assert( t==0x00 );
          pParse->hasNonstd = 1;
          t = 0x01;
          for(j=i+3; sqlite3Isxdigit(z[j]); j++){}
          goto parse_number_finish;
        }else if( sqlite3Isdigit(z[i+1]) ){
          pParse->iErr = i+1;
          return -1;
        }
      }else{
        if( !sqlite3Isdigit(z[i+1]) ){
          /* JSON5 allows for "+Infinity" and "-Infinity" using exactly
          ** that case.  SQLite also allows these in any case and it allows
          ** "+inf" and "-inf". */
          if( (z[i+1]=='I' || z[i+1]=='i')
           && sqlite3StrNICmp(&z[i+1], "inf",3)==0
          ){
            pParse->hasNonstd = 1;
            if( z[i]=='-' ){
              jsonBlobAppendNode(pParse, JSONB_FLOAT, 6, "-9e999");
            }else{
              jsonBlobAppendNode(pParse, JSONB_FLOAT, 5, "9e999");
            }
            return i + (sqlite3StrNICmp(&z[i+4],"inity",5)==0 ? 9 : 4);
          }
          if( z[i+1]=='.' ){
            pParse->hasNonstd = 1;
            t |= 0x01;
            goto parse_number_2;
          }
          pParse->iErr = i;
          return -1;
        }
        if( z[i+1]=='0' ){
          if( sqlite3Isdigit(z[i+2]) ){
            pParse->iErr = i+1;
            return -1;
          }else if( (z[i+2]=='x' || z[i+2]=='X') && sqlite3Isxdigit(z[i+3]) ){
            pParse->hasNonstd = 1;
            t |= 0x01;
            for(j=i+4; sqlite3Isxdigit(z[j]); j++){}
            goto parse_number_finish;
          }
        }
      }
    }

  parse_number_2:
    for(j=i+1;; j++){
      c = z[j];
      if( sqlite3Isdigit(c) ) continue;
      if( c=='.' ){
        if( (t & 0x02)!=0 ){
          pParse->iErr = j;
          return -1;
        }
        t |= 0x02;
        continue;
      }
      if( c=='e' || c=='E' ){
        if( z[j-1]<'0' ){
          if( ALWAYS(z[j-1]=='.') && ALWAYS(j-2>=i) && sqlite3Isdigit(z[j-2]) ){
            pParse->hasNonstd = 1;
            t |= 0x01;
          }else{
            pParse->iErr = j;
            return -1;
          }
        }
        if( seenE ){
          pParse->iErr = j;
          return -1;
        }
        t |= 0x02;
        seenE = 1;
        c = z[j+1];
        if( c=='+' || c=='-' ){
          j++;
          c = z[j+1];
        }
        if( c<'0' || c>'9' ){
          pParse->iErr = j;
          return -1;
        }
        continue;
      }
      break;
    }
    if( z[j-1]<'0' ){
      if( ALWAYS(z[j-1]=='.') && ALWAYS(j-2>=i) && sqlite3Isdigit(z[j-2]) ){
        pParse->hasNonstd = 1;
        t |= 0x01;
      }else{
        pParse->iErr = j;
        return -1;
      }
    }
  parse_number_finish:
    assert( JSONB_INT+0x01==JSONB_INT5 );
    assert( JSONB_FLOAT+0x01==JSONB_FLOAT5 );
    assert( JSONB_INT+0x02==JSONB_FLOAT );
    if( z[i]=='+' ) i++;
    jsonBlobAppendNode(pParse, JSONB_INT+t, j-i, &z[i]);
    return j;
  }
  case '}': {
    pParse->iErr = i;
    return -2;  /* End of {...} */
  }
  case ']': {