sqllogictest

/******************************************************************************
** This file is an amalgamation of many separate C source files from SQLite
** version 3.41.0.  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

** 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        "3.41.0"
#define SQLITE_VERSION_NUMBER 3041000
#define SQLITE_SOURCE_ID      "2023-02-06 16:23:52 5dde07a91dcf99b9c9a418b4e2178f66eef4cffd4799538a419674314a7530f9"

/*
** CAPI3REF: Run-Time Library Version Numbers
** KEYWORDS: sqlite3_version sqlite3_sourceid
**
** These interfaces provide the same information as the [SQLITE_VERSION],
** [SQLITE_VERSION_NUMBER], and [SQLITE_SOURCE_ID] C preprocessor macros

#define SQLITE_CONSTRAINT_UNIQUE       (SQLITE_CONSTRAINT | (8<<8))
#define SQLITE_CONSTRAINT_VTAB         (SQLITE_CONSTRAINT | (9<<8))
#define SQLITE_CONSTRAINT_ROWID        (SQLITE_CONSTRAINT |(10<<8))
#define SQLITE_CONSTRAINT_PINNED       (SQLITE_CONSTRAINT |(11<<8))
#define SQLITE_CONSTRAINT_DATATYPE     (SQLITE_CONSTRAINT |(12<<8))
#define SQLITE_NOTICE_RECOVER_WAL      (SQLITE_NOTICE | (1<<8))
#define SQLITE_NOTICE_RECOVER_ROLLBACK (SQLITE_NOTICE | (2<<8))
#define SQLITE_NOTICE_RBU              (SQLITE_NOTICE | (3<<8))
#define SQLITE_WARNING_AUTOINDEX       (SQLITE_WARNING | (1<<8))
#define SQLITE_AUTH_USER               (SQLITE_AUTH | (1<<8))
#define SQLITE_OK_LOAD_PERMANENTLY     (SQLITE_OK | (1<<8))
#define SQLITE_OK_SYMLINK              (SQLITE_OK | (2<<8)) /* internal use only */

/*
** CAPI3REF: Flags For File Open Operations

#define SQLITE_IOCAP_BATCH_ATOMIC           0x00004000

/*
** CAPI3REF: File Locking Levels
**
** SQLite uses one of these integer values as the second
** argument to calls it makes to the xLock() and xUnlock() methods
** of an [sqlite3_io_methods] object.  These values are ordered from
** lest restrictive to most restrictive.
**
** The argument to xLock() is always SHARED or higher.  The argument to
** xUnlock is either SHARED or NONE.
*/
#define SQLITE_LOCK_NONE          0       /* xUnlock() only */
#define SQLITE_LOCK_SHARED        1       /* xLock() or xUnlock() */
#define SQLITE_LOCK_RESERVED      2       /* xLock() only */
#define SQLITE_LOCK_PENDING       3       /* xLock() only */
#define SQLITE_LOCK_EXCLUSIVE     4       /* xLock() only */

/*
** CAPI3REF: Synchronization Type Flags
**
** When SQLite invokes the xSync() method of an
** [sqlite3_io_methods] object it uses a combination of
** these integer values as the second argument.

** <ul>
** <li> [SQLITE_LOCK_NONE],
** <li> [SQLITE_LOCK_SHARED],
** <li> [SQLITE_LOCK_RESERVED],
** <li> [SQLITE_LOCK_PENDING], or
** <li> [SQLITE_LOCK_EXCLUSIVE].
** </ul>
** xLock() upgrades the database file lock.  In other words, xLock() moves the
** database file lock in the direction NONE toward EXCLUSIVE. The argument to
** xLock() is always on of SHARED, RESERVED, PENDING, or EXCLUSIVE, never
** SQLITE_LOCK_NONE.  If the database file lock is already at or above the
** requested lock, then the call to xLock() is a no-op.
** xUnlock() downgrades the database file lock to either SHARED or NONE.
*  If the lock is already at or below the requested lock state, then the call
** to xUnlock() is a no-op.
** The xCheckReservedLock() method checks whether any database connection,
** either in this process or in some other process, is holding a RESERVED,
** PENDING, or EXCLUSIVE lock on the file.  It returns true
** if such a lock exists and false otherwise.
**
** The xFileControl() method is a generic interface that allows custom
** VFS implementations to directly control an open file using the

**
** <ul>
** <li>[[SQLITE_FCNTL_LOCKSTATE]]
** The [SQLITE_FCNTL_LOCKSTATE] opcode is used for debugging.  This
** opcode causes the xFileControl method to write the current state of
** the lock (one of [SQLITE_LOCK_NONE], [SQLITE_LOCK_SHARED],
** [SQLITE_LOCK_RESERVED], [SQLITE_LOCK_PENDING], or [SQLITE_LOCK_EXCLUSIVE])
** into an integer that the pArg argument points to.
** This capability is only available if SQLite is compiled with [SQLITE_DEBUG].

**
** <li>[[SQLITE_FCNTL_SIZE_HINT]]
** The [SQLITE_FCNTL_SIZE_HINT] opcode is used by SQLite to give the VFS
** layer a hint of how large the database file will grow to be during the
** current transaction.  This hint is not guaranteed to be accurate but it
** is often close.  The underlying VFS might choose to preallocate database
** file space based on this hint in order to help writes to the database

** the database is not a wal-mode db, or if there is no such connection in any
** other process. This opcode cannot be used to detect transactions opened
** by clients within the current process, only within other processes.
** </ul>
**
** <li>[[SQLITE_FCNTL_CKSM_FILE]]
** Used by the cksmvfs VFS module only.
**
** <li>[[SQLITE_FCNTL_RESET_CACHE]]
** If there is currently no transaction open on the database, and the
** database is not a temp db, then this file-control purges the contents
** of the in-memory page cache. If there is an open transaction, or if
** the db is a temp-db, it is a no-op, not an error.
** </ul>
*/
#define SQLITE_FCNTL_LOCKSTATE               1
#define SQLITE_FCNTL_GET_LOCKPROXYFILE       2
#define SQLITE_FCNTL_SET_LOCKPROXYFILE       3
#define SQLITE_FCNTL_LAST_ERRNO              4
#define SQLITE_FCNTL_SIZE_HINT               5

#define SQLITE_FCNTL_DATA_VERSION           35
#define SQLITE_FCNTL_SIZE_LIMIT             36
#define SQLITE_FCNTL_CKPT_DONE              37
#define SQLITE_FCNTL_RESERVE_BYTES          38
#define SQLITE_FCNTL_CKPT_START             39
#define SQLITE_FCNTL_EXTERNAL_READER        40
#define SQLITE_FCNTL_CKSM_FILE              41
#define SQLITE_FCNTL_RESET_CACHE            42

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

** A pointer to the opaque sqlite3_api_routines structure is passed as
** the third parameter to entry points of [loadable extensions].  This
** structure must be typedefed in order to work around compiler warnings
** on some platforms.
*/
typedef struct sqlite3_api_routines sqlite3_api_routines;

/*
** CAPI3REF: File Name
**
** Type [sqlite3_filename] is used by SQLite to pass filenames to the
** xOpen method of a [VFS]. It may be cast to (const char*) and treated
** as a normal, nul-terminated, UTF-8 buffer containing the filename, but
** may also be passed to special APIs such as:
**
** <ul>
** <li>  sqlite3_filename_database()
** <li>  sqlite3_filename_journal()
** <li>  sqlite3_filename_wal()
** <li>  sqlite3_uri_parameter()
** <li>  sqlite3_uri_boolean()
** <li>  sqlite3_uri_int64()
** <li>  sqlite3_uri_key()
** </ul>
*/
typedef const char *sqlite3_filename;

/*
** CAPI3REF: OS Interface Object
**
** An instance of the sqlite3_vfs object defines the interface between
** the SQLite core and the underlying operating system.  The "vfs"
** in the name of the object stands for "virtual file system".  See
** the [VFS | VFS documentation] for further information.

struct sqlite3_vfs {
  int iVersion;            /* Structure version number (currently 3) */
  int szOsFile;            /* Size of subclassed sqlite3_file */
  int mxPathname;          /* Maximum file pathname length */
  sqlite3_vfs *pNext;      /* Next registered VFS */
  const char *zName;       /* Name of this virtual file system */
  void *pAppData;          /* Pointer to application-specific data */
  int (*xOpen)(sqlite3_vfs*, sqlite3_filename zName, sqlite3_file*,
               int flags, int *pOutFlags);
  int (*xDelete)(sqlite3_vfs*, const char *zName, int syncDir);
  int (*xAccess)(sqlite3_vfs*, const char *zName, int flags, int *pResOut);
  int (*xFullPathname)(sqlite3_vfs*, const char *zName, int nOut, char *zOut);
  void *(*xDlOpen)(sqlite3_vfs*, const char *zFilename);
  void (*xDlError)(sqlite3_vfs*, int nByte, char *zErrMsg);
  void (*(*xDlSym)(sqlite3_vfs*,void*, const char *zSymbol))(void);

** or equal to the product of the second and third arguments.  The buffer
** must be aligned to an 8-byte boundary.  ^If the second argument to
** SQLITE_DBCONFIG_LOOKASIDE is not a multiple of 8, it is internally
** rounded down to the next smaller multiple of 8.  ^(The lookaside memory
** configuration for a database connection can only be changed when that
** connection is not currently using lookaside memory, or in other words
** when the "current value" returned by
** [sqlite3_db_status](D,[SQLITE_DBSTATUS_LOOKASIDE_USED],...) is zero.
** Any attempt to change the lookaside memory configuration when lookaside
** memory is in use leaves the configuration unchanged and returns
** [SQLITE_BUSY].)^</dd>
**
** [[SQLITE_DBCONFIG_ENABLE_FKEY]]
** <dt>SQLITE_DBCONFIG_ENABLE_FKEY</dt>
** <dd> ^This option is used to enable or disable the enforcement of

**      the database in WAL mode after the reset if it was in WAL mode before
**      the reset.
** <li> sqlite3_db_config(db, SQLITE_DBCONFIG_RESET_DATABASE, 1, 0);
** <li> [sqlite3_exec](db, "[VACUUM]", 0, 0, 0);
** <li> sqlite3_db_config(db, SQLITE_DBCONFIG_RESET_DATABASE, 0, 0);
** </ol>
** Because resetting a database is destructive and irreversible, the
** process requires the use of this obscure API and multiple steps to
** help ensure that it does not happen by accident. Because this
** feature must be capable of resetting corrupt databases, and
** shutting down virtual tables may require access to that corrupt
** storage, the library must abandon any installed virtual tables
** without calling their xDestroy() methods.
**
** [[SQLITE_DBCONFIG_DEFENSIVE]] <dt>SQLITE_DBCONFIG_DEFENSIVE</dt>
** <dd>The SQLITE_DBCONFIG_DEFENSIVE option activates or deactivates the
** "defensive" flag for a database connection.  When the defensive
** flag is enabled, language features that allow ordinary SQL to
** deliberately corrupt the database file are disabled.  The disabled
** features include but are not limited to the following:
** <ul>
** <li> The [PRAGMA writable_schema=ON] statement.
** <li> The [PRAGMA journal_mode=OFF] statement.
** <li> The [PRAGMA schema_version=N] statement.
** <li> Writes to the [sqlite_dbpage] virtual table.
** <li> Direct writes to [shadow tables].
** </ul>
** </dd>
**
** [[SQLITE_DBCONFIG_WRITABLE_SCHEMA]] <dt>SQLITE_DBCONFIG_WRITABLE_SCHEMA</dt>
** <dd>The SQLITE_DBCONFIG_WRITABLE_SCHEMA option activates or deactivates the

** running statement count reaches zero are interrupted as if they had been
** running prior to the sqlite3_interrupt() call.  ^New SQL statements
** that are started after the running statement count reaches zero are
** not effected by the sqlite3_interrupt().
** ^A call to sqlite3_interrupt(D) that occurs when there are no running
** SQL statements is a no-op and has no effect on SQL statements
** that are started after the sqlite3_interrupt() call returns.
**
** ^The [sqlite3_is_interrupted(D)] interface can be used to determine whether
** or not an interrupt is currently in effect for [database connection] D.
*/
SQLITE_API void sqlite3_interrupt(sqlite3*);
SQLITE_API int sqlite3_is_interrupted(sqlite3*);

/*
** CAPI3REF: Determine If An SQL Statement Is Complete
**
** These routines are useful during command-line input to determine if the
** currently entered text seems to form a complete SQL statement or
** if additional input is needed before sending the text into

** interface by using the X argument when X begins with "--" and invoking
** [sqlite3_expanded_sql(P)] otherwise.
**
** [[SQLITE_TRACE_PROFILE]] <dt>SQLITE_TRACE_PROFILE</dt>
** <dd>^An SQLITE_TRACE_PROFILE callback provides approximately the same
** information as is provided by the [sqlite3_profile()] callback.
** ^The P argument is a pointer to the [prepared statement] and the
** X argument points to a 64-bit integer which is approximately
** the number of nanoseconds that the prepared statement took to run.
** ^The SQLITE_TRACE_PROFILE callback is invoked when the statement finishes.
**
** [[SQLITE_TRACE_ROW]] <dt>SQLITE_TRACE_ROW</dt>
** <dd>^An SQLITE_TRACE_ROW callback is invoked whenever a prepared
** statement generates a single row of result.
** ^The P argument is a pointer to the [prepared statement] and the
** X argument is unused.

/*
** CAPI3REF: Query Progress Callbacks
** METHOD: sqlite3
**
** ^The sqlite3_progress_handler(D,N,X,P) interface causes the callback
** function X to be invoked periodically during long running calls to
** [sqlite3_step()] and [sqlite3_prepare()] and similar for
** database connection D.  An example use for this
** interface is to keep a GUI updated during a large query.
**
** ^The parameter P is passed through as the only parameter to the
** callback function X.  ^The parameter N is the approximate number of
** [virtual machine instructions] that are evaluated between successive
** invocations of the callback X.  ^If N is less than one then the progress

** "Cancel" button on a GUI progress dialog box.
**
** The progress handler callback must not do anything that will modify
** the database connection that invoked the progress handler.
** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
** database connections for the meaning of "modify" in this paragraph.
**
** The progress handler callback would originally only be invoked from the
** bytecode engine.  It still might be invoked during [sqlite3_prepare()]
** and similar because those routines might force a reparse of the schema
** which involves running the bytecode engine.  However, beginning with
** SQLite version 3.41.0, the progress handler callback might also be
** invoked directly from [sqlite3_prepare()] while analyzing and generating
** code for complex queries.
*/
SQLITE_API void sqlite3_progress_handler(sqlite3*, int, int(*)(void*), void*);

/*
** CAPI3REF: Opening A New Database Connection
** CONSTRUCTOR: sqlite3
**

** except that it accepts two additional parameters for additional control
** over the new database connection.  ^(The flags parameter to
** sqlite3_open_v2() must include, at a minimum, one of the following
** three flag combinations:)^
**
** <dl>
** ^(<dt>[SQLITE_OPEN_READONLY]</dt>
** <dd>The database is opened in read-only mode.  If the database does
** not already exist, an error is returned.</dd>)^
**
** ^(<dt>[SQLITE_OPEN_READWRITE]</dt>
** <dd>The database is opened for reading and writing if possible, or
** reading only if the file is write protected by the operating
** system.  In either case the database must already exist, otherwise
** an error is returned.  For historical reasons, if opening in
** read-write mode fails due to OS-level permissions, an attempt is
** made to open it in read-only mode. [sqlite3_db_readonly()] can be
** used to determine whether the database is actually
** read-write.</dd>)^
**
** ^(<dt>[SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]</dt>
** <dd>The database is opened for reading and writing, and is created if
** it does not already exist. This is the behavior that is always used for
** sqlite3_open() and sqlite3_open16().</dd>)^
** </dl>
**

** (Mutexes will block any actual concurrency, but in this mode
** there is no harm in trying.)
**
** ^(<dt>[SQLITE_OPEN_SHAREDCACHE]</dt>
** <dd>The database is opened [shared cache] enabled, overriding
** the default shared cache setting provided by
** [sqlite3_enable_shared_cache()].)^
** The [use of shared cache mode is discouraged] and hence shared cache
** capabilities may be omitted from many builds of SQLite.  In such cases,
** this option is a no-op.
**
** ^(<dt>[SQLITE_OPEN_PRIVATECACHE]</dt>
** <dd>The database is opened [shared cache] disabled, overriding
** the default shared cache setting provided by
** [sqlite3_enable_shared_cache()].)^
**
** [[OPEN_EXRESCODE]] ^(<dt>[SQLITE_OPEN_EXRESCODE]</dt>
** <dd>The database connection comes up in "extended result code mode".
** In other words, the database behaves has if
** [sqlite3_extended_result_codes(db,1)] where called on the database
** connection as soon as the connection is created. In addition to setting
** the extended result code mode, this flag also causes [sqlite3_open_v2()]
** to return an extended result code.</dd>
**
** [[OPEN_NOFOLLOW]] ^(<dt>[SQLITE_OPEN_NOFOLLOW]</dt>
** <dd>The database filename is not allowed to contain a symbolic link</dd>
** </dl>)^
**
** If the 3rd parameter to sqlite3_open_v2() is not one of the
** required combinations shown above optionally combined with other
** [SQLITE_OPEN_READONLY | SQLITE_OPEN_* bits]
** then the behavior is undefined.  Historic versions of SQLite
** have silently ignored surplus bits in the flags parameter to

** routines would only work if F was the name of the main database file.
** When the F parameter is the name of the rollback journal or WAL file,
** it has access to all the same query parameters as were found on the
** main database file.
**
** See the [URI filename] documentation for additional information.
*/
SQLITE_API const char *sqlite3_uri_parameter(sqlite3_filename z, const char *zParam);
SQLITE_API int sqlite3_uri_boolean(sqlite3_filename z, const char *zParam, int bDefault);
SQLITE_API sqlite3_int64 sqlite3_uri_int64(sqlite3_filename, const char*, sqlite3_int64);
SQLITE_API const char *sqlite3_uri_key(sqlite3_filename z, int N);

/*
** CAPI3REF:  Translate filenames
**
** These routines are available to [VFS|custom VFS implementations] for
** translating filenames between the main database file, the journal file,
** and the WAL file.

** WAL file.
**
** In all of the above, if F is not the name of a database, journal or WAL
** filename passed into the VFS from the SQLite core and F is not the
** return value from [sqlite3_db_filename()], then the result is
** undefined and is likely a memory access violation.
*/
SQLITE_API const char *sqlite3_filename_database(sqlite3_filename);
SQLITE_API const char *sqlite3_filename_journal(sqlite3_filename);
SQLITE_API const char *sqlite3_filename_wal(sqlite3_filename);

/*
** CAPI3REF:  Database File Corresponding To A Journal
**
** ^If X is the name of a rollback or WAL-mode journal file that is
** passed into the xOpen method of [sqlite3_vfs], then
** sqlite3_database_file_object(X) returns a pointer to the [sqlite3_file]

** sqlite3_create_filename(), then bad things such as heap
** corruption or segfaults may occur. The value Y should not be
** used again after sqlite3_free_filename(Y) has been called.  This means
** that if the [sqlite3_vfs.xOpen()] method of a VFS has been called using Y,
** then the corresponding [sqlite3_module.xClose() method should also be
** invoked prior to calling sqlite3_free_filename(Y).
*/
SQLITE_API sqlite3_filename sqlite3_create_filename(
  const char *zDatabase,
  const char *zJournal,
  const char *zWal,
  int nParam,
  const char **azParam
);
SQLITE_API void sqlite3_free_filename(sqlite3_filename);

/*
** CAPI3REF: Error Codes And Messages
** METHOD: sqlite3
**
** ^If the most recent sqlite3_* API call associated with
** [database connection] D failed, then the sqlite3_errcode(D) interface

** </dd>
**
** [[SQLITE_DIRECTONLY]] <dt>SQLITE_DIRECTONLY</dt><dd>
** The SQLITE_DIRECTONLY flag means that the function may only be invoked
** from top-level SQL, and cannot be used in VIEWs or TRIGGERs nor in
** schema structures such as [CHECK constraints], [DEFAULT clauses],
** [expression indexes], [partial indexes], or [generated columns].
** <p>
** The SQLITE_DIRECTONLY flag is recommended for any
** [application-defined SQL function]
** that has side-effects or that could potentially leak sensitive information.
** This will prevent attacks in which an application is tricked
** into using a database file that has had its schema surreptiously
** modified to invoke the application-defined function in ways that are
** harmful.
** <p>
** Some people say it is good practice to set SQLITE_DIRECTONLY on all
** [application-defined SQL functions], regardless of whether or not they
** are security sensitive, as doing so prevents those functions from being used
** inside of the database schema, and thus ensures that the database
** can be inspected and modified using generic tools (such as the [CLI])
** that do not have access to the application-defined functions.
** </dd>
**
** [[SQLITE_INNOCUOUS]] <dt>SQLITE_INNOCUOUS</dt><dd>
** The SQLITE_INNOCUOUS flag means that the function is unlikely
** to cause problems even if misused.  An innocuous function should have
** no side effects and should not depend on any values other than its
** input parameters. The [abs|abs() function] is an example of an

SQLITE_API int sqlite3_value_bytes(sqlite3_value*);
SQLITE_API int sqlite3_value_bytes16(sqlite3_value*);
SQLITE_API int sqlite3_value_type(sqlite3_value*);
SQLITE_API int sqlite3_value_numeric_type(sqlite3_value*);
SQLITE_API int sqlite3_value_nochange(sqlite3_value*);
SQLITE_API int sqlite3_value_frombind(sqlite3_value*);

/*
** CAPI3REF: Report the internal text encoding state of an sqlite3_value object
** METHOD: sqlite3_value
**
** ^(The sqlite3_value_encoding(X) interface returns one of [SQLITE_UTF8],
** [SQLITE_UTF16BE], or [SQLITE_UTF16LE] according to the current text encoding
** of the value X, assuming that X has type TEXT.)^  If sqlite3_value_type(X)
** returns something other than SQLITE_TEXT, then the return value from
** sqlite3_value_encoding(X) is meaningless.  ^Calls to
** [sqlite3_value_text(X)], [sqlite3_value_text16(X)], [sqlite3_value_text16be(X)],
** [sqlite3_value_text16le(X)], [sqlite3_value_bytes(X)], or
** [sqlite3_value_bytes16(X)] might change the encoding of the value X and
** thus change the return from subsequent calls to sqlite3_value_encoding(X).
**
** This routine is intended for used by applications that test and validate
** the SQLite implementation.  This routine is inquiring about the opaque
** internal state of an [sqlite3_value] object.  Ordinary applications should
** not need to know what the internal state of an sqlite3_value object is and
** hence should not need to use this interface.
*/
SQLITE_API int sqlite3_value_encoding(sqlite3_value*);

/*
** CAPI3REF: Finding The Subtype Of SQL Values
** 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

** an aggregate query, the xStep() callback of the aggregate function
** implementation is never called and xFinal() is called exactly once.
** In those cases, sqlite3_aggregate_context() might be called for the
** first time from within xFinal().)^
**
** ^The sqlite3_aggregate_context(C,N) routine returns a NULL pointer
** when first called if N is less than or equal to zero or if a memory
** allocation error occurs.
**
** ^(The amount of space allocated by sqlite3_aggregate_context(C,N) is
** determined by the N parameter on first successful call.  Changing the
** value of N in any subsequent call to sqlite3_aggregate_context() within
** the same aggregate function instance will not resize the memory
** allocation.)^  Within the xFinal callback, it is customary to set
** N=0 in calls to sqlite3_aggregate_context(C,N) so that no

** UTF-16 little endian, or UTF-16 big endian, respectively.
** ^The sqlite3_result_text64() interface sets the return value of an
** application-defined function to be a text string in an encoding
** specified by the fifth (and last) parameter, which must be one
** of [SQLITE_UTF8], [SQLITE_UTF16], [SQLITE_UTF16BE], or [SQLITE_UTF16LE].
** ^SQLite takes the text result from the application from
** the 2nd parameter of the sqlite3_result_text* interfaces.
** ^If the 3rd parameter to any of the sqlite3_result_text* interfaces
** other than sqlite3_result_text64() is negative, then SQLite computes
** the string length itself by searching the 2nd parameter for the first
** zero character.
** ^If the 3rd parameter to the sqlite3_result_text* interfaces
** is non-negative, then as many bytes (not characters) of the text
** pointed to by the 2nd parameter are taken as the application-defined
** function result.  If the 3rd parameter is non-negative, then it
** must be the byte offset into the string where the NUL terminator would
** appear if the string where NUL terminated.  If any NUL characters occur
** in the string at a byte offset that is less than the value of the 3rd

/*
** CAPI3REF: Return The Schema Name For A Database Connection
** METHOD: sqlite3
**
** ^The sqlite3_db_name(D,N) interface returns a pointer to the schema name
** for the N-th database on database connection D, or a NULL pointer of N is
** out of range.  An N value of 0 means the main database file.  An N of 1 is
** the "temp" schema.  Larger values of N correspond to various ATTACH-ed
** databases.
**
** Space to hold the string that is returned by sqlite3_db_name() is managed
** by SQLite itself.  The string might be deallocated by any operation that
** changes the schema, including [ATTACH] or [DETACH] or calls to
** [sqlite3_serialize()] or [sqlite3_deserialize()], even operations that

** <li> [sqlite3_uri_boolean()]
** <li> [sqlite3_uri_int64()]
** <li> [sqlite3_filename_database()]
** <li> [sqlite3_filename_journal()]
** <li> [sqlite3_filename_wal()]
** </ul>
*/
SQLITE_API sqlite3_filename sqlite3_db_filename(sqlite3 *db, const char *zDbName);

/*
** CAPI3REF: Determine if a database is read-only
** METHOD: sqlite3
**
** ^The sqlite3_db_readonly(D,N) interface returns 1 if the database N
** of connection D is read-only, 0 if it is read/write, or -1 if N is not

** CAPI3REF: Autovacuum Compaction Amount Callback
** METHOD: sqlite3
**
** ^The sqlite3_autovacuum_pages(D,C,P,X) interface registers a callback
** function C that is invoked prior to each autovacuum of the database
** file.  ^The callback is passed a copy of the generic data pointer (P),
** the schema-name of the attached database that is being autovacuumed,
** the size of the database file in pages, the number of free pages,
** and the number of bytes per page, respectively.  The callback should
** return the number of free pages that should be removed by the
** autovacuum.  ^If the callback returns zero, then no autovacuum happens.
** ^If the value returned is greater than or equal to the number of
** free pages, then a complete autovacuum happens.
**
** <p>^If there are multiple ATTACH-ed database files that are being

** CAPI3REF: Enable Or Disable Shared Pager Cache
**
** ^(This routine enables or disables the sharing of the database cache
** and schema data structures between [database connection | connections]
** to the same database. Sharing is enabled if the argument is true
** and disabled if the argument is false.)^
**
** This interface is omitted if SQLite is compiled with
** [-DSQLITE_OMIT_SHARED_CACHE].  The [-DSQLITE_OMIT_SHARED_CACHE]
** compile-time option is recommended because the
** [use of shared cache mode is discouraged].
**
** ^Cache sharing is enabled and disabled for an entire process.
** This is a change as of SQLite [version 3.5.0] ([dateof:3.5.0]).
** In prior versions of SQLite,
** sharing was enabled or disabled for each thread separately.
**
** ^(The cache sharing mode set by this interface effects all subsequent
** calls to [sqlite3_open()], [sqlite3_open_v2()], and [sqlite3_open16()].

** sqlite3_soft_heap_limit64(-1) or sqlite3_hard_heap_limit(-1).
**
** ^Setting the heap limits to zero disables the heap limiter mechanism.
**
** ^The soft heap limit may not be greater than the hard heap limit.
** ^If the hard heap limit is enabled and if sqlite3_soft_heap_limit(N)
** is invoked with a value of N that is greater than the hard heap limit,
** the soft heap limit is set to the value of the hard heap limit.
** ^The soft heap limit is automatically enabled whenever the hard heap
** limit is enabled. ^When sqlite3_hard_heap_limit64(N) is invoked and
** the soft heap limit is outside the range of 1..N, then the soft heap
** limit is set to N.  ^Invoking sqlite3_soft_heap_limit64(0) when the
** hard heap limit is enabled makes the soft heap limit equal to the
** hard heap limit.
**

** CAPI3REF: Reset Automatic Extension Loading
**
** ^This interface disables all automatic extensions previously
** registered using [sqlite3_auto_extension()].
*/
SQLITE_API void sqlite3_reset_auto_extension(void);










/*
** Structures used by the virtual table interface
*/
typedef struct sqlite3_vtab sqlite3_vtab;
typedef struct sqlite3_index_info sqlite3_index_info;
typedef struct sqlite3_vtab_cursor sqlite3_vtab_cursor;
typedef struct sqlite3_module sqlite3_module;

** aConstraintUsage[].omit flag is an optimization hint. When the omit flag
** is left in its default setting of false, the constraint will always be
** checked separately in byte code.  If the omit flag is change to true, then
** the constraint may or may not be checked in byte code.  In other words,
** when the omit flag is true there is no guarantee that the constraint will
** not be checked again using byte code.)^
**
** ^The idxNum and idxStr values are recorded and passed into the
** [xFilter] method.
** ^[sqlite3_free()] is used to free idxStr if and only if
** needToFreeIdxStr is true.
**
** ^The orderByConsumed means that output from [xFilter]/[xNext] will occur in
** the correct order to satisfy the ORDER BY clause so that no separate
** sorting step is required.
**
** ^The estimatedCost value is an estimate of the cost of a particular
** strategy. A cost of N indicates that the cost of the strategy is similar

** and hence calls to sqlite3_vtab_rhs_value() for those operators will
** always return SQLITE_NOTFOUND.
**
** The collating sequence to be used for comparison can be found using
** the [sqlite3_vtab_collation()] interface.  For most real-world virtual
** tables, the collating sequence of constraints does not matter (for example
** because the constraints are numeric) and so the sqlite3_vtab_collation()
** interface is not commonly needed.
*/
#define SQLITE_INDEX_CONSTRAINT_EQ          2
#define SQLITE_INDEX_CONSTRAINT_GT          4
#define SQLITE_INDEX_CONSTRAINT_LE          8
#define SQLITE_INDEX_CONSTRAINT_LT         16
#define SQLITE_INDEX_CONSTRAINT_GE         32
#define SQLITE_INDEX_CONSTRAINT_MATCH      64

** before this API is called, a new function is created.)^  ^The implementation
** of the new function always causes an exception to be thrown.  So
** the new function is not good for anything by itself.  Its only
** purpose is to be a placeholder function that can be overloaded
** by a [virtual table].
*/
SQLITE_API int sqlite3_overload_function(sqlite3*, const char *zFuncName, int nArg);











/*
** CAPI3REF: A Handle To An Open BLOB
** KEYWORDS: {BLOB handle} {BLOB handles}
**
** An instance of this object represents an open BLOB on which
** [sqlite3_blob_open | incremental BLOB I/O] can be performed.

** However, the application must guarantee that the destination
** [database connection] is not passed to any other API (by any thread) after
** sqlite3_backup_init() is called and before the corresponding call to
** sqlite3_backup_finish().  SQLite does not currently check to see
** if the application incorrectly accesses the destination [database connection]
** and so no error code is reported, but the operations may malfunction
** nevertheless.  Use of the destination database connection while a
** backup is in progress might also cause a mutex deadlock.
**
** If running in [shared cache mode], the application must
** guarantee that the shared cache used by the destination database
** is not accessed while the backup is running. In practice this means
** that the application must guarantee that the disk file being
** backed up to is not accessed by any connection within the process,
** not just the specific connection that was passed to sqlite3_backup_init().

** These constants define all valid values for the "checkpoint mode" passed
** as the third parameter to the [sqlite3_wal_checkpoint_v2()] interface.
** See the [sqlite3_wal_checkpoint_v2()] documentation for details on the
** meaning of each of these checkpoint modes.
*/
#define SQLITE_CHECKPOINT_PASSIVE  0  /* Do as much as possible w/o blocking */
#define SQLITE_CHECKPOINT_FULL     1  /* Wait for writers, then checkpoint */
#define SQLITE_CHECKPOINT_RESTART  2  /* Like FULL but wait for readers */
#define SQLITE_CHECKPOINT_TRUNCATE 3  /* Like RESTART but also truncate WAL */

/*
** CAPI3REF: Virtual Table Interface Configuration
**
** This function may be called by either the [xConnect] or [xCreate] method
** of a [virtual table] implementation to configure

**         of the constraint specifies an alternative collating sequence via
**         a [COLLATE clause] on the column definition within the CREATE TABLE
**         statement that was passed into [sqlite3_declare_vtab()], then the
**         name of that alternative collating sequence is returned.
** <li><p> Otherwise, "BINARY" is returned.
** </ol>
*/
SQLITE_API const char *sqlite3_vtab_collation(sqlite3_index_info*,int);

/*
** CAPI3REF: Determine if a virtual table query is DISTINCT
** METHOD: sqlite3_index_info
**
** This API may only be used from within an [xBestIndex|xBestIndex method]
** of a [virtual table] implementation. The result of calling this

**
** These interfaces are only useful from within the
** [xFilter|xFilter() method] of a [virtual table] implementation.
** The result of invoking these interfaces from any other context
** is undefined and probably harmful.
**
** The X parameter in a call to sqlite3_vtab_in_first(X,P) or
** sqlite3_vtab_in_next(X,P) should be one of the parameters to the
** xFilter method which invokes these routines, and specifically
** a parameter that was previously selected for all-at-once IN constraint
** processing use the [sqlite3_vtab_in()] interface in the
** [xBestIndex|xBestIndex method].  ^(If the X parameter is not
** an xFilter argument that was selected for all-at-once IN constraint
** processing, then these routines return [SQLITE_ERROR].)^

**
** ^(Use these routines to access all values on the right-hand side
** of the IN constraint using code like the following:
**
** <blockquote><pre>
** &nbsp;  for(rc=sqlite3_vtab_in_first(pList, &pVal);
** &nbsp;      rc==SQLITE_OK && pVal

** [sqlite3_stmt_scanstatus(S,X,T,V)] interface.  Each constant designates a
** different metric for sqlite3_stmt_scanstatus() to return.
**
** When the value returned to V is a string, space to hold that string is
** managed by the prepared statement S and will be automatically freed when
** S is finalized.
**
** Not all values are available for all query elements. When a value is
** not available, the output variable is set to -1 if the value is numeric,
** or to NULL if it is a string (SQLITE_SCANSTAT_NAME).
**
** <dl>
** [[SQLITE_SCANSTAT_NLOOP]] <dt>SQLITE_SCANSTAT_NLOOP</dt>
** <dd>^The [sqlite3_int64] variable pointed to by the V parameter will be
** set to the total number of times that the X-th loop has run.</dd>
**
** [[SQLITE_SCANSTAT_NVISIT]] <dt>SQLITE_SCANSTAT_NVISIT</dt>
** <dd>^The [sqlite3_int64] variable pointed to by the V parameter will be set

** used for the X-th loop.
**
** [[SQLITE_SCANSTAT_EXPLAIN]] <dt>SQLITE_SCANSTAT_EXPLAIN</dt>
** <dd>^The "const char *" variable pointed to by the V parameter will be set
** to a zero-terminated UTF-8 string containing the [EXPLAIN QUERY PLAN]
** description for the X-th loop.
**
** [[SQLITE_SCANSTAT_SELECTID]] <dt>SQLITE_SCANSTAT_SELECTID</dt>
** <dd>^The "int" variable pointed to by the V parameter will be set to the
** id for the X-th query plan element. The id value is unique within the

** statement. The select-id is the same value as is output in the first
** column of an [EXPLAIN QUERY PLAN] query.
** </dl>
**
** [[SQLITE_SCANSTAT_PARENTID]] <dt>SQLITE_SCANSTAT_PARENTID</dt>
** <dd>The "int" variable pointed to by the V parameter will be set to the
** the id of the parent of the current query element, if applicable, or
** to zero if the query element has no parent. This is the same value as
** returned in the second column of an [EXPLAIN QUERY PLAN] query.
**
** [[SQLITE_SCANSTAT_NCYCLE]] <dt>SQLITE_SCANSTAT_NCYCLE</dt>
** <dd>The sqlite3_int64 output value is set to the number of cycles,
** according to the processor time-stamp counter, that elapsed while the
** query element was being processed. This value is not available for
** all query elements - if it is unavailable the output variable is
** set to -1.
*/
#define SQLITE_SCANSTAT_NLOOP    0
#define SQLITE_SCANSTAT_NVISIT   1
#define SQLITE_SCANSTAT_EST      2
#define SQLITE_SCANSTAT_NAME     3
#define SQLITE_SCANSTAT_EXPLAIN  4
#define SQLITE_SCANSTAT_SELECTID 5
#define SQLITE_SCANSTAT_PARENTID 6
#define SQLITE_SCANSTAT_NCYCLE   7

/*
** CAPI3REF: Prepared Statement Scan Status
** METHOD: sqlite3_stmt
**
** These interfaces return information about the predicted and measured
** performance for pStmt.  Advanced applications can use this
** interface to compare the predicted and the measured performance and
** issue warnings and/or rerun [ANALYZE] if discrepancies are found.
**
** Since this interface is expected to be rarely used, it is only
** available if SQLite is compiled using the [SQLITE_ENABLE_STMT_SCANSTATUS]
** compile-time option.
**
** The "iScanStatusOp" parameter determines which status information to return.
** The "iScanStatusOp" must be one of the [scanstatus options] or the behavior
** of this interface is undefined. ^The requested measurement is written into

** a variable pointed to by the "pOut" parameter.
**
** The "flags" parameter must be passed a mask of flags. At present only
** one flag is defined - SQLITE_SCANSTAT_COMPLEX. If SQLITE_SCANSTAT_COMPLEX
** is specified, then status information is available for all elements
** of a query plan that are reported by "EXPLAIN QUERY PLAN" output. If
** SQLITE_SCANSTAT_COMPLEX is not specified, then only query plan elements
** that correspond to query loops (the "SCAN..." and "SEARCH..." elements of
** the EXPLAIN QUERY PLAN output) are available. Invoking API
** sqlite3_stmt_scanstatus() is equivalent to calling
** sqlite3_stmt_scanstatus_v2() with a zeroed flags parameter.
**
** Parameter "idx" identifies the specific query element to retrieve statistics
** for. Query elements are numbered starting from zero. A value of -1 may be
** to query for statistics regarding the entire query. ^If idx is out of range
** - less than -1 or greater than or equal to the total number of query
** elements used to implement the statement - a non-zero value is returned and
** the variable that pOut points to is unchanged.





**
** See also: [sqlite3_stmt_scanstatus_reset()]
*/
SQLITE_API int sqlite3_stmt_scanstatus(
  sqlite3_stmt *pStmt,      /* Prepared statement for which info desired */
  int idx,                  /* Index of loop to report on */
  int iScanStatusOp,        /* Information desired.  SQLITE_SCANSTAT_* */
  void *pOut                /* Result written here */
);
SQLITE_API int sqlite3_stmt_scanstatus_v2(
  sqlite3_stmt *pStmt,      /* Prepared statement for which info desired */
  int idx,                  /* Index of loop to report on */
  int iScanStatusOp,        /* Information desired.  SQLITE_SCANSTAT_* */
  int flags,                /* Mask of flags defined below */
  void *pOut                /* Result written here */
);

/*
** CAPI3REF: Prepared Statement Scan Status
** KEYWORDS: {scan status flags}
*/
#define SQLITE_SCANSTAT_COMPLEX 0x0001

/*
** CAPI3REF: Zero Scan-Status Counters
** METHOD: sqlite3_stmt
**
** ^Zero all [sqlite3_stmt_scanstatus()] related event counters.
**

** or any operation on a WITHOUT ROWID table, the value of the sixth
** parameter is undefined. For an INSERT or UPDATE on a rowid table the
** seventh parameter is the final rowid value of the row being inserted
** or updated. The value of the seventh parameter passed to the callback
** function is not defined for operations on WITHOUT ROWID tables, or for
** DELETE operations on rowid tables.
**
** ^The sqlite3_update_hook(D,C,P) function returns the P argument from
** the previous call on the same [database connection] D, or NULL for
** the first call on D.
**
** The [sqlite3_preupdate_old()], [sqlite3_preupdate_new()],
** [sqlite3_preupdate_count()], and [sqlite3_preupdate_depth()] interfaces
** provide additional information about a preupdate event. These routines
** may only be called from within a preupdate callback.  Invoking any of
** these routines from outside of a preupdate callback or with a
** [database connection] pointer that is different from the one supplied
** to the preupdate callback results in undefined and probably undesirable

#endif /* _FTS5_H */

/******** End of fts5.h *********/

/************** End of sqlite3.h *********************************************/
/************** Continuing where we left off in sqliteInt.h ******************/

/*
** Reuse the STATIC_LRU for mutex access to sqlite3_temp_directory.
*/
#define SQLITE_MUTEX_STATIC_TEMPDIR SQLITE_MUTEX_STATIC_VFS1

/*
** Include the configuration header output by 'configure' if we're using the
** autoconf-based build
*/
#if defined(_HAVE_SQLITE_CONFIG_H) && !defined(SQLITECONFIG_H)
#include "sqlite_cfg.h"
#define SQLITECONFIG_H 1
#endif

/************** Include sqliteLimit.h in the middle of sqliteInt.h ***********/
/************** Begin file sqliteLimit.h *************************************/
/*
** 2007 May 7

** all alignment restrictions correct.
**
** Except, if SQLITE_4_BYTE_ALIGNED_MALLOC is defined, then the
** underlying malloc() implementation might return us 4-byte aligned
** pointers.  In that case, only verify 4-byte alignment.
*/
#ifdef SQLITE_4_BYTE_ALIGNED_MALLOC
# define EIGHT_BYTE_ALIGNMENT(X)   ((((uptr)(X) - (uptr)0)&3)==0)
#else
# define EIGHT_BYTE_ALIGNMENT(X)   ((((uptr)(X) - (uptr)0)&7)==0)
#endif

/*
** Disable MMAP on platforms where it is known to not work
*/
#if defined(__OpenBSD__) || defined(__QNXNTO__)
# undef SQLITE_MAX_MMAP_SIZE

#if !defined(SQLITE_AMALGAMATION)
SQLITE_PRIVATE u32 sqlite3TreeTrace;
#endif
#if defined(SQLITE_DEBUG) \
    && (defined(SQLITE_TEST) || defined(SQLITE_ENABLE_SELECTTRACE) \
                             || defined(SQLITE_ENABLE_TREETRACE))
# define TREETRACE_ENABLED 1
# define TREETRACE(K,P,S,X)  \
  if(sqlite3TreeTrace&(K))   \
    sqlite3DebugPrintf("%u/%d/%p: ",(S)->selId,(P)->addrExplain,(S)),\
    sqlite3DebugPrintf X
#else
# define TREETRACE(K,P,S,X)
# define TREETRACE_ENABLED 0
#endif

/* TREETRACE flag meanings:
**
**   0x00000001     Beginning and end of SELECT processing
**   0x00000002     WHERE clause processing
**   0x00000004     Query flattener
**   0x00000008     Result-set wildcard expansion
**   0x00000010     Query name resolution
**   0x00000020     Aggregate analysis
**   0x00000040     Window functions
**   0x00000080     Generated column names
**   0x00000100     Move HAVING terms into WHERE
**   0x00000200     Count-of-view optimization
**   0x00000400     Compound SELECT processing
**   0x00000800     Drop superfluous ORDER BY
**   0x00001000     LEFT JOIN simplifies to JOIN
**   0x00002000     Constant propagation
**   0x00004000     Push-down optimization
**   0x00008000     After all FROM-clause analysis
**   0x00010000     Beginning of DELETE/INSERT/UPDATE processing
**   0x00020000     Transform DISTINCT into GROUP BY
**   0x00040000     SELECT tree dump after all code has been generated
*/

/*
** Macros for "wheretrace"
*/
SQLITE_PRIVATE u32 sqlite3WhereTrace;
#if defined(SQLITE_DEBUG) \
    && (defined(SQLITE_TEST) || defined(SQLITE_ENABLE_WHERETRACE))
# define WHERETRACE(K,X)  if(sqlite3WhereTrace&(K)) sqlite3DebugPrintf X
# define WHERETRACE_ENABLED 1
#else
# define WHERETRACE(K,X)
#endif

/*
** Bits for the sqlite3WhereTrace mask:
**
** (---any--)   Top-level block structure
** 0x-------F   High-level debug messages
** 0x----FFF-   More detail
** 0xFFFF----   Low-level debug messages
**
** 0x00000001   Code generation
** 0x00000002   Solver
** 0x00000004   Solver costs
** 0x00000008   WhereLoop inserts
**
** 0x00000010   Display sqlite3_index_info xBestIndex calls
** 0x00000020   Range an equality scan metrics
** 0x00000040   IN operator decisions
** 0x00000080   WhereLoop cost adjustements
** 0x00000100
** 0x00000200   Covering index decisions
** 0x00000400   OR optimization
** 0x00000800   Index scanner
** 0x00001000   More details associated with code generation
** 0x00002000
** 0x00004000   Show all WHERE terms at key points
** 0x00008000   Show the full SELECT statement at key places
**
** 0x00010000   Show more detail when printing WHERE terms
** 0x00020000   Show WHERE terms returned from whereScanNext()
*/


/*
** An instance of the following structure is used to store the busy-handler
** callback for a given sqlite handle.
**
** The sqlite.busyHandler member of the sqlite struct contains the busy
** callback for the database handle. Each pager opened via the sqlite

typedef struct ExprList ExprList;
typedef struct FKey FKey;
typedef struct FuncDestructor FuncDestructor;
typedef struct FuncDef FuncDef;
typedef struct FuncDefHash FuncDefHash;
typedef struct IdList IdList;
typedef struct Index Index;
typedef struct IndexedExpr IndexedExpr;
typedef struct IndexSample IndexSample;
typedef struct KeyClass KeyClass;
typedef struct KeyInfo KeyInfo;
typedef struct Lookaside Lookaside;
typedef struct LookasideSlot LookasideSlot;
typedef struct Module Module;
typedef struct NameContext NameContext;

** A bit in a Bitmask
*/
#define MASKBIT(n)    (((Bitmask)1)<<(n))
#define MASKBIT64(n)  (((u64)1)<<(n))
#define MASKBIT32(n)  (((unsigned int)1)<<(n))
#define SMASKBIT32(n) ((n)<=31?((unsigned int)1)<<(n):0)
#define ALLBITS       ((Bitmask)-1)
#define TOPBIT        (((Bitmask)1)<<(BMS-1))

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

/*
** Defer sourcing vdbe.h and btree.h until after the "u8" and
** "BusyHandler" typedefs. vdbe.h also requires a few of the opaque
** pointer types (i.e. FuncDef) defined above.
*/
/************** Include os.h in the middle of sqliteInt.h ********************/
/************** Begin file os.h **********************************************/
/*
** 2001 September 16
**
** The author disclaims copyright to this source code.  In place of
** a legal notice, here is a blessing:
**
**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
******************************************************************************
**
** This header file (together with is companion C source-code file
** "os.c") attempt to abstract the underlying operating system so that
** the SQLite library will work on both POSIX and windows systems.
**
** This header file is #include-ed by sqliteInt.h and thus ends up
** being included by every source file.
*/
#ifndef _SQLITE_OS_H_
#define _SQLITE_OS_H_

/*
** Attempt to automatically detect the operating system and setup the
** necessary pre-processor macros for it.
*/
/************** Include os_setup.h in the middle of os.h *********************/
/************** Begin file os_setup.h ****************************************/
/*
** 2013 November 25
**
** The author disclaims copyright to this source code.  In place of
** a legal notice, here is a blessing:
**
**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
******************************************************************************
**
** This file contains pre-processor directives related to operating system
** detection and/or setup.
*/
#ifndef SQLITE_OS_SETUP_H
#define SQLITE_OS_SETUP_H

/*
** Figure out if we are dealing with Unix, Windows, or some other operating
** system.
**
** After the following block of preprocess macros, all of
**
**    SQLITE_OS_KV
**    SQLITE_OS_OTHER
**    SQLITE_OS_UNIX
**    SQLITE_OS_WIN
**
** will defined to either 1 or 0. One of them will be 1. The others will be 0.
** If none of the macros are initially defined, then select either
** SQLITE_OS_UNIX or SQLITE_OS_WIN depending on the target platform.
**
** If SQLITE_OS_OTHER=1 is specified at compile-time, then the application
** must provide its own VFS implementation together with sqlite3_os_init()
** and sqlite3_os_end() routines.
*/
#if !defined(SQLITE_OS_KV) && !defined(SQLITE_OS_OTHER) && \
       !defined(SQLITE_OS_UNIX) && !defined(SQLITE_OS_WIN)
#  if defined(_WIN32) || defined(WIN32) || defined(__CYGWIN__) || \
          defined(__MINGW32__) || defined(__BORLANDC__)
#    define SQLITE_OS_WIN 1
#    define SQLITE_OS_UNIX 0
#  else
#    define SQLITE_OS_WIN 0
#    define SQLITE_OS_UNIX 1
#  endif
#endif
#if SQLITE_OS_OTHER+1>1
#  undef SQLITE_OS_KV
#  define SQLITE_OS_KV 0
#  undef SQLITE_OS_UNIX
#  define SQLITE_OS_UNIX 0
#  undef SQLITE_OS_WIN
#  define SQLITE_OS_WIN 0
#endif
#if SQLITE_OS_KV+1>1
#  undef SQLITE_OS_OTHER
#  define SQLITE_OS_OTHER 0
#  undef SQLITE_OS_UNIX
#  define SQLITE_OS_UNIX 0
#  undef SQLITE_OS_WIN
#  define SQLITE_OS_WIN 0
#  define SQLITE_OMIT_LOAD_EXTENSION 1
#  define SQLITE_OMIT_WAL 1
#  define SQLITE_OMIT_DEPRECATED 1
#  undef SQLITE_TEMP_STORE
#  define SQLITE_TEMP_STORE 3  /* Always use memory for temporary storage */
#  define SQLITE_DQS 0
#  define SQLITE_OMIT_SHARED_CACHE 1
#  define SQLITE_OMIT_AUTOINIT 1
#endif
#if SQLITE_OS_UNIX+1>1
#  undef SQLITE_OS_KV
#  define SQLITE_OS_KV 0
#  undef SQLITE_OS_OTHER
#  define SQLITE_OS_OTHER 0
#  undef SQLITE_OS_WIN
#  define SQLITE_OS_WIN 0
#endif
#if SQLITE_OS_WIN+1>1
#  undef SQLITE_OS_KV
#  define SQLITE_OS_KV 0
#  undef SQLITE_OS_OTHER
#  define SQLITE_OS_OTHER 0
#  undef SQLITE_OS_UNIX
#  define SQLITE_OS_UNIX 0
#endif


#endif /* SQLITE_OS_SETUP_H */

/************** End of os_setup.h ********************************************/
/************** Continuing where we left off in os.h *************************/

/* If the SET_FULLSYNC macro is not defined above, then make it
** a no-op
*/
#ifndef SET_FULLSYNC
# define SET_FULLSYNC(x,y)
#endif

/* Maximum pathname length.  Note: FILENAME_MAX defined by stdio.h
*/
#ifndef SQLITE_MAX_PATHLEN
# define SQLITE_MAX_PATHLEN FILENAME_MAX
#endif

/* Maximum number of symlinks that will be resolved while trying to
** expand a filename in xFullPathname() in the VFS.
*/
#ifndef SQLITE_MAX_SYMLINK
# define SQLITE_MAX_SYMLINK 200
#endif

/*
** The default size of a disk sector
*/
#ifndef SQLITE_DEFAULT_SECTOR_SIZE
# define SQLITE_DEFAULT_SECTOR_SIZE 4096
#endif

/*
** Temporary files are named starting with this prefix followed by 16 random
** alphanumeric characters, and no file extension. They are stored in the
** OS's standard temporary file directory, and are deleted prior to exit.
** If sqlite is being embedded in another program, you may wish to change the
** prefix to reflect your program's name, so that if your program exits
** prematurely, old temporary files can be easily identified. This can be done
** using -DSQLITE_TEMP_FILE_PREFIX=myprefix_ on the compiler command line.
**
** 2006-10-31:  The default prefix used to be "sqlite_".  But then
** Mcafee started using SQLite in their anti-virus product and it
** started putting files with the "sqlite" name in the c:/temp folder.
** This annoyed many windows users.  Those users would then do a
** Google search for "sqlite", find the telephone numbers of the
** developers and call to wake them up at night and complain.
** For this reason, the default name prefix is changed to be "sqlite"
** spelled backwards.  So the temp files are still identified, but
** anybody smart enough to figure out the code is also likely smart
** enough to know that calling the developer will not help get rid
** of the file.
*/
#ifndef SQLITE_TEMP_FILE_PREFIX
# define SQLITE_TEMP_FILE_PREFIX "etilqs_"
#endif

/*
** The following values may be passed as the second argument to
** sqlite3OsLock(). The various locks exhibit the following semantics:
**
** SHARED:    Any number of processes may hold a SHARED lock simultaneously.
** RESERVED:  A single process may hold a RESERVED lock on a file at
**            any time. Other processes may hold and obtain new SHARED locks.
** PENDING:   A single process may hold a PENDING lock on a file at
**            any one time. Existing SHARED locks may persist, but no new
**            SHARED locks may be obtained by other processes.
** EXCLUSIVE: An EXCLUSIVE lock precludes all other locks.
**
** PENDING_LOCK may not be passed directly to sqlite3OsLock(). Instead, a
** process that requests an EXCLUSIVE lock may actually obtain a PENDING
** lock. This can be upgraded to an EXCLUSIVE lock by a subsequent call to
** sqlite3OsLock().
*/
#define NO_LOCK         0
#define SHARED_LOCK     1
#define RESERVED_LOCK   2
#define PENDING_LOCK    3
#define EXCLUSIVE_LOCK  4

/*
** File Locking Notes:  (Mostly about windows but also some info for Unix)
**
** We cannot use LockFileEx() or UnlockFileEx() on Win95/98/ME because
** those functions are not available.  So we use only LockFile() and
** UnlockFile().
**
** LockFile() prevents not just writing but also reading by other processes.
** A SHARED_LOCK is obtained by locking a single randomly-chosen
** byte out of a specific range of bytes. The lock byte is obtained at
** random so two separate readers can probably access the file at the
** same time, unless they are unlucky and choose the same lock byte.
** An EXCLUSIVE_LOCK is obtained by locking all bytes in the range.
** There can only be one writer.  A RESERVED_LOCK is obtained by locking
** a single byte of the file that is designated as the reserved lock byte.
** A PENDING_LOCK is obtained by locking a designated byte different from
** the RESERVED_LOCK byte.
**
** On WinNT/2K/XP systems, LockFileEx() and UnlockFileEx() are available,
** which means we can use reader/writer locks.  When reader/writer locks
** are used, the lock is placed on the same range of bytes that is used
** for probabilistic locking in Win95/98/ME.  Hence, the locking scheme
** will support two or more Win95 readers or two or more WinNT readers.
** But a single Win95 reader will lock out all WinNT readers and a single
** WinNT reader will lock out all other Win95 readers.
**
** The following #defines specify the range of bytes used for locking.
** SHARED_SIZE is the number of bytes available in the pool from which
** a random byte is selected for a shared lock.  The pool of bytes for
** shared locks begins at SHARED_FIRST.
**
** The same locking strategy and
** byte ranges are used for Unix.  This leaves open the possibility of having
** clients on win95, winNT, and unix all talking to the same shared file
** and all locking correctly.  To do so would require that samba (or whatever
** tool is being used for file sharing) implements locks correctly between
** windows and unix.  I'm guessing that isn't likely to happen, but by
** using the same locking range we are at least open to the possibility.
**
** Locking in windows is manditory.  For this reason, we cannot store
** actual data in the bytes used for locking.  The pager never allocates
** the pages involved in locking therefore.  SHARED_SIZE is selected so
** that all locks will fit on a single page even at the minimum page size.
** PENDING_BYTE defines the beginning of the locks.  By default PENDING_BYTE
** is set high so that we don't have to allocate an unused page except
** for very large databases.  But one should test the page skipping logic
** by setting PENDING_BYTE low and running the entire regression suite.
**
** Changing the value of PENDING_BYTE results in a subtly incompatible
** file format.  Depending on how it is changed, you might not notice
** the incompatibility right away, even running a full regression test.
** The default location of PENDING_BYTE is the first byte past the
** 1GB boundary.
**
*/
#ifdef SQLITE_OMIT_WSD
# define PENDING_BYTE     (0x40000000)
#else
# define PENDING_BYTE      sqlite3PendingByte
#endif
#define RESERVED_BYTE     (PENDING_BYTE+1)
#define SHARED_FIRST      (PENDING_BYTE+2)
#define SHARED_SIZE       510

/*
** Wrapper around OS specific sqlite3_os_init() function.
*/
SQLITE_PRIVATE int sqlite3OsInit(void);

/*
** Functions for accessing sqlite3_file methods
*/
SQLITE_PRIVATE void sqlite3OsClose(sqlite3_file*);
SQLITE_PRIVATE int sqlite3OsRead(sqlite3_file*, void*, int amt, i64 offset);
SQLITE_PRIVATE int sqlite3OsWrite(sqlite3_file*, const void*, int amt, i64 offset);
SQLITE_PRIVATE int sqlite3OsTruncate(sqlite3_file*, i64 size);
SQLITE_PRIVATE int sqlite3OsSync(sqlite3_file*, int);
SQLITE_PRIVATE int sqlite3OsFileSize(sqlite3_file*, i64 *pSize);
SQLITE_PRIVATE int sqlite3OsLock(sqlite3_file*, int);
SQLITE_PRIVATE int sqlite3OsUnlock(sqlite3_file*, int);
SQLITE_PRIVATE int sqlite3OsCheckReservedLock(sqlite3_file *id, int *pResOut);
SQLITE_PRIVATE int sqlite3OsFileControl(sqlite3_file*,int,void*);
SQLITE_PRIVATE void sqlite3OsFileControlHint(sqlite3_file*,int,void*);
#define SQLITE_FCNTL_DB_UNCHANGED 0xca093fa0
SQLITE_PRIVATE int sqlite3OsSectorSize(sqlite3_file *id);
SQLITE_PRIVATE int sqlite3OsDeviceCharacteristics(sqlite3_file *id);
#ifndef SQLITE_OMIT_WAL
SQLITE_PRIVATE int sqlite3OsShmMap(sqlite3_file *,int,int,int,void volatile **);
SQLITE_PRIVATE int sqlite3OsShmLock(sqlite3_file *id, int, int, int);
SQLITE_PRIVATE void sqlite3OsShmBarrier(sqlite3_file *id);
SQLITE_PRIVATE int sqlite3OsShmUnmap(sqlite3_file *id, int);
#endif /* SQLITE_OMIT_WAL */
SQLITE_PRIVATE int sqlite3OsFetch(sqlite3_file *id, i64, int, void **);
SQLITE_PRIVATE int sqlite3OsUnfetch(sqlite3_file *, i64, void *);


/*
** Functions for accessing sqlite3_vfs methods
*/
SQLITE_PRIVATE int sqlite3OsOpen(sqlite3_vfs *, const char *, sqlite3_file*, int, int *);
SQLITE_PRIVATE int sqlite3OsDelete(sqlite3_vfs *, const char *, int);
SQLITE_PRIVATE int sqlite3OsAccess(sqlite3_vfs *, const char *, int, int *pResOut);
SQLITE_PRIVATE int sqlite3OsFullPathname(sqlite3_vfs *, const char *, int, char *);
#ifndef SQLITE_OMIT_LOAD_EXTENSION
SQLITE_PRIVATE void *sqlite3OsDlOpen(sqlite3_vfs *, const char *);
SQLITE_PRIVATE void sqlite3OsDlError(sqlite3_vfs *, int, char *);
SQLITE_PRIVATE void (*sqlite3OsDlSym(sqlite3_vfs *, void *, const char *))(void);
SQLITE_PRIVATE void sqlite3OsDlClose(sqlite3_vfs *, void *);
#endif /* SQLITE_OMIT_LOAD_EXTENSION */
SQLITE_PRIVATE int sqlite3OsRandomness(sqlite3_vfs *, int, char *);
SQLITE_PRIVATE int sqlite3OsSleep(sqlite3_vfs *, int);
SQLITE_PRIVATE int sqlite3OsGetLastError(sqlite3_vfs*);
SQLITE_PRIVATE int sqlite3OsCurrentTimeInt64(sqlite3_vfs *, sqlite3_int64*);

/*
** Convenience functions for opening and closing files using
** sqlite3_malloc() to obtain space for the file-handle structure.
*/
SQLITE_PRIVATE int sqlite3OsOpenMalloc(sqlite3_vfs *, const char *, sqlite3_file **, int,int*);
SQLITE_PRIVATE void sqlite3OsCloseFree(sqlite3_file *);

#endif /* _SQLITE_OS_H_ */

/************** End of os.h **************************************************/
/************** Continuing where we left off in sqliteInt.h ******************/
/************** Include pager.h in the middle of sqliteInt.h *****************/
/************** Begin file pager.h *******************************************/
/*
** 2001 September 15
**
** The author disclaims copyright to this source code.  In place of
** a legal notice, here is a blessing:

**
**     The design of the _RANGE hint is aid b-tree implementations that try
**     to prefetch content from remote machines - to provide those
**     implementations with limits on what needs to be prefetched and thereby
**     reduce network bandwidth.
**
** Note that BTREE_HINT_FLAGS with BTREE_BULKLOAD is the only hint used by
** standard SQLite.  The other hints are provided for extensions that use
** the SQLite parser and code generator but substitute their own storage
** engine.
*/
#define BTREE_HINT_RANGE 0       /* Range constraints on queries */

/*
** Values that may be OR'd together to form the argument to the

SQLITE_PRIVATE i64 sqlite3BtreeOffset(BtCursor*);
#endif
SQLITE_PRIVATE int sqlite3BtreePayload(BtCursor*, u32 offset, u32 amt, void*);
SQLITE_PRIVATE const void *sqlite3BtreePayloadFetch(BtCursor*, u32 *pAmt);
SQLITE_PRIVATE u32 sqlite3BtreePayloadSize(BtCursor*);
SQLITE_PRIVATE sqlite3_int64 sqlite3BtreeMaxRecordSize(BtCursor*);

SQLITE_PRIVATE int sqlite3BtreeIntegrityCheck(
  sqlite3 *db,  /* Database connection that is running the check */
  Btree *p,     /* The btree to be checked */
  Pgno *aRoot,  /* An array of root pages numbers for individual trees */
  int nRoot,    /* Number of entries in aRoot[] */
  int mxErr,    /* Stop reporting errors after this many */
  int *pnErr,   /* OUT: Write number of errors seen to this variable */
  char **pzOut  /* OUT: Write the error message string here */
);
SQLITE_PRIVATE struct Pager *sqlite3BtreePager(Btree*);
SQLITE_PRIVATE i64 sqlite3BtreeRowCountEst(BtCursor*);

#ifndef SQLITE_OMIT_INCRBLOB
SQLITE_PRIVATE int sqlite3BtreePayloadChecked(BtCursor*, u32 offset, u32 amt, void*);
SQLITE_PRIVATE int sqlite3BtreePutData(BtCursor*, u32 offset, u32 amt, void*);
SQLITE_PRIVATE void sqlite3BtreeIncrblobCursor(BtCursor *);

#ifndef SQLITE_OMIT_WAL
SQLITE_PRIVATE   int sqlite3BtreeCheckpoint(Btree*, int, int *, int *);
#endif

SQLITE_PRIVATE int sqlite3BtreeTransferRow(BtCursor*, BtCursor*, i64);

SQLITE_PRIVATE void sqlite3BtreeClearCache(Btree*);

/*
** If we are not using shared cache, then there is no need to
** use mutexes to access the BtShared structures.  So make the
** Enter and Leave procedures no-ops.
*/
#ifndef SQLITE_OMIT_SHARED_CACHE
SQLITE_PRIVATE   void sqlite3BtreeEnter(Btree*);

#ifdef SQLITE_ENABLE_CURSOR_HINTS
    Expr *pExpr;           /* Used when p4type is P4_EXPR */
#endif
  } p4;
#ifdef SQLITE_ENABLE_EXPLAIN_COMMENTS
  char *zComment;          /* Comment to improve readability */
#endif




#ifdef SQLITE_VDBE_COVERAGE
  u32 iSrcLine;            /* Source-code line that generated this opcode
                           ** with flags in the upper 8 bits */
#endif
#if defined(SQLITE_ENABLE_STMT_SCANSTATUS) || defined(VDBE_PROFILE)
  u64 nExec;
  u64 nCycle;
#endif
};
typedef struct VdbeOp VdbeOp;


/*
** A sub-routine used to implement a trigger program.
*/

#define OP_AutoCommit      1
#define OP_Transaction     2
#define OP_Checkpoint      3
#define OP_JournalMode     4
#define OP_Vacuum          5
#define OP_VFilter         6 /* jump, synopsis: iplan=r[P3] zplan='P4'     */
#define OP_VUpdate         7 /* synopsis: data=r[P3@P2]                    */
#define OP_Init            8 /* jump, synopsis: Start at P2                */
#define OP_Goto            9 /* jump                                       */
#define OP_Gosub          10 /* jump                                       */
#define OP_InitCoroutine  11 /* jump                                       */
#define OP_Yield          12 /* jump                                       */
#define OP_MustBeInt      13 /* jump                                       */
#define OP_Jump           14 /* jump                                       */
#define OP_Once           15 /* jump                                       */
#define OP_If             16 /* jump                                       */
#define OP_IfNot          17 /* jump                                       */
#define OP_IsType         18 /* jump, synopsis: if typeof(P1.P3) in P5 goto P2 */

#define OP_Not            19 /* same as TK_NOT, synopsis: r[P2]= !r[P1]    */
#define OP_IfNullRow      20 /* jump, synopsis: if P1.nullRow then r[P3]=NULL, goto P2 */
#define OP_SeekLT         21 /* jump, synopsis: key=r[P3@P4]               */
#define OP_SeekLE         22 /* jump, synopsis: key=r[P3@P4]               */
#define OP_SeekGE         23 /* jump, synopsis: key=r[P3@P4]               */
#define OP_SeekGT         24 /* jump, synopsis: key=r[P3@P4]               */
#define OP_IfNotOpen      25 /* jump, synopsis: if( !csr[P1] ) goto P2     */
#define OP_IfNoHope       26 /* jump, synopsis: key=r[P3@P4]               */
#define OP_NoConflict     27 /* jump, synopsis: key=r[P3@P4]               */
#define OP_NotFound       28 /* jump, synopsis: key=r[P3@P4]               */
#define OP_Found          29 /* jump, synopsis: key=r[P3@P4]               */
#define OP_SeekRowid      30 /* jump, synopsis: intkey=r[P3]               */
#define OP_NotExists      31 /* jump, synopsis: intkey=r[P3]               */
#define OP_Last           32 /* jump                                       */
#define OP_IfSmaller      33 /* jump                                       */
#define OP_SorterSort     34 /* jump                                       */
#define OP_Sort           35 /* jump                                       */
#define OP_Rewind         36 /* jump                                       */
#define OP_SorterNext     37 /* jump                                       */
#define OP_Prev           38 /* jump                                       */
#define OP_Next           39 /* jump                                       */

#define OP_IdxLE          40 /* jump, synopsis: key=r[P3@P4]               */
#define OP_IdxGT          41 /* jump, synopsis: key=r[P3@P4]               */
#define OP_IdxLT          42 /* jump, synopsis: key=r[P3@P4]               */
#define OP_Or             43 /* same as TK_OR, synopsis: r[P3]=(r[P1] || r[P2]) */
#define OP_And            44 /* same as TK_AND, synopsis: r[P3]=(r[P1] && r[P2]) */
#define OP_IdxGE          45 /* jump, synopsis: key=r[P3@P4]               */
#define OP_RowSetRead     46 /* jump, synopsis: r[P3]=rowset(P1)           */
#define OP_RowSetTest     47 /* jump, synopsis: if r[P3] in rowset(P1) goto P2 */
#define OP_Program        48 /* jump                                       */
#define OP_FkIfZero       49 /* jump, synopsis: if fkctr[P1]==0 goto P2    */

#define OP_IsNull         50 /* jump, same as TK_ISNULL, synopsis: if r[P1]==NULL goto P2 */
#define OP_NotNull        51 /* jump, same as TK_NOTNULL, synopsis: if r[P1]!=NULL goto P2 */
#define OP_Ne             52 /* jump, same as TK_NE, synopsis: IF r[P3]!=r[P1] */
#define OP_Eq             53 /* jump, same as TK_EQ, synopsis: IF r[P3]==r[P1] */
#define OP_Gt             54 /* jump, same as TK_GT, synopsis: IF r[P3]>r[P1] */
#define OP_Le             55 /* jump, same as TK_LE, synopsis: IF r[P3]<=r[P1] */
#define OP_Lt             56 /* jump, same as TK_LT, synopsis: IF r[P3]<r[P1] */
#define OP_Ge             57 /* jump, same as TK_GE, synopsis: IF r[P3]>=r[P1] */
#define OP_ElseEq         58 /* jump, same as TK_ESCAPE                    */
#define OP_IfPos          59 /* jump, synopsis: if r[P1]>0 then r[P1]-=P3, goto P2 */
#define OP_IfNotZero      60 /* jump, synopsis: if r[P1]!=0 then r[P1]--, goto P2 */
#define OP_DecrJumpZero   61 /* jump, synopsis: if (--r[P1])==0 goto P2    */
#define OP_IncrVacuum     62 /* jump                                       */
#define OP_VNext          63 /* jump                                       */
#define OP_Filter         64 /* jump, synopsis: if key(P3@P4) not in filter(P1) goto P2 */

#define OP_PureFunc       65 /* synopsis: r[P3]=func(r[P2@NP])             */
#define OP_Function       66 /* synopsis: r[P3]=func(r[P2@NP])             */
#define OP_Return         67
#define OP_EndCoroutine   68
#define OP_HaltIfNull     69 /* synopsis: if r[P3]=null halt               */
#define OP_Halt           70
#define OP_Integer        71 /* synopsis: r[P2]=P1                         */

*/
#define OPFLG_JUMP        0x01  /* jump:  P2 holds jmp target */
#define OPFLG_IN1         0x02  /* in1:   P1 is an input */
#define OPFLG_IN2         0x04  /* in2:   P2 is an input */
#define OPFLG_IN3         0x08  /* in3:   P3 is an input */
#define OPFLG_OUT2        0x10  /* out2:  P2 is an output */
#define OPFLG_OUT3        0x20  /* out3:  P3 is an output */
#define OPFLG_NCYCLE      0x40  /* ncycle:Cycles count against P1 */
#define OPFLG_INITIALIZER {\
/*   0 */ 0x00, 0x00, 0x00, 0x00, 0x10, 0x00, 0x41, 0x00,\
/*   8 */ 0x01, 0x01, 0x01, 0x01, 0x03, 0x03, 0x01, 0x01,\
/*  16 */ 0x03, 0x03, 0x01, 0x12, 0x01, 0x49, 0x49, 0x49,\
/*  24 */ 0x49, 0x01, 0x49, 0x49, 0x49, 0x49, 0x49, 0x49,\
/*  32 */ 0x41, 0x01, 0x01, 0x01, 0x41, 0x01, 0x41, 0x41,\
/*  40 */ 0x41, 0x41, 0x41, 0x26, 0x26, 0x41, 0x23, 0x0b,\
/*  48 */ 0x01, 0x01, 0x03, 0x03, 0x0b, 0x0b, 0x0b, 0x0b,\
/*  56 */ 0x0b, 0x0b, 0x01, 0x03, 0x03, 0x03, 0x01, 0x41,\
/*  64 */ 0x01, 0x00, 0x00, 0x02, 0x02, 0x08, 0x00, 0x10,\
/*  72 */ 0x10, 0x10, 0x00, 0x10, 0x00, 0x10, 0x10, 0x00,\
/*  80 */ 0x00, 0x10, 0x10, 0x00, 0x00, 0x00, 0x02, 0x02,\
/*  88 */ 0x02, 0x00, 0x00, 0x12, 0x1e, 0x20, 0x40, 0x00,\
/*  96 */ 0x00, 0x00, 0x10, 0x10, 0x00, 0x40, 0x26, 0x26,\
/* 104 */ 0x26, 0x26, 0x26, 0x26, 0x26, 0x26, 0x26, 0x26,\
/* 112 */ 0x40, 0x00, 0x12, 0x40, 0x40, 0x10, 0x40, 0x00,\
/* 120 */ 0x00, 0x00, 0x40, 0x00, 0x40, 0x40, 0x10, 0x10,\
/* 128 */ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 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, 0x50, 0x40,\
/* 176 */ 0x00, 0x10, 0x10, 0x02, 0x00, 0x00, 0x00, 0x00,\
/* 184 */ 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

SQLITE_PRIVATE   void sqlite3VdbeNoJumpsOutsideSubrtn(Vdbe*,int,int,int);
#else
# define sqlite3VdbeVerifyAbortable(A,B)
# define sqlite3VdbeNoJumpsOutsideSubrtn(A,B,C,D)
#endif
SQLITE_PRIVATE VdbeOp *sqlite3VdbeAddOpList(Vdbe*, int nOp, VdbeOpList const *aOp,int iLineno);
#ifndef SQLITE_OMIT_EXPLAIN
SQLITE_PRIVATE   int sqlite3VdbeExplain(Parse*,u8,const char*,...);
SQLITE_PRIVATE   void sqlite3VdbeExplainPop(Parse*);
SQLITE_PRIVATE   int sqlite3VdbeExplainParent(Parse*);
# define ExplainQueryPlan(P)        sqlite3VdbeExplain P
# ifdef SQLITE_ENABLE_STMT_SCANSTATUS
#  define ExplainQueryPlan2(V,P)     (V = sqlite3VdbeExplain P)
# else
#  define ExplainQueryPlan2(V,P)     ExplainQueryPlan(P)
# endif
# define ExplainQueryPlanPop(P)     sqlite3VdbeExplainPop(P)
# define ExplainQueryPlanParent(P)  sqlite3VdbeExplainParent(P)
#else
# define ExplainQueryPlan(P)
# define ExplainQueryPlan2(V,P)
# define ExplainQueryPlanPop(P)
# define ExplainQueryPlanParent(P) 0
# define sqlite3ExplainBreakpoint(A,B) /*no-op*/
#endif
#if defined(SQLITE_DEBUG) && !defined(SQLITE_OMIT_EXPLAIN)
SQLITE_PRIVATE   void sqlite3ExplainBreakpoint(const char*,const char*);
#else
# define sqlite3ExplainBreakpoint(A,B) /*no-op*/
#endif
SQLITE_PRIVATE void sqlite3VdbeAddParseSchemaOp(Vdbe*, int, char*, u16);
SQLITE_PRIVATE void sqlite3VdbeChangeOpcode(Vdbe*, int addr, u8);
SQLITE_PRIVATE void sqlite3VdbeChangeP1(Vdbe*, int addr, int P1);
SQLITE_PRIVATE void sqlite3VdbeChangeP2(Vdbe*, int addr, int P2);
SQLITE_PRIVATE void sqlite3VdbeChangeP3(Vdbe*, int addr, int P3);
SQLITE_PRIVATE void sqlite3VdbeChangeP5(Vdbe*, u16 P5);
SQLITE_PRIVATE void sqlite3VdbeTypeofColumn(Vdbe*, int);
SQLITE_PRIVATE void sqlite3VdbeJumpHere(Vdbe*, int addr);
SQLITE_PRIVATE void sqlite3VdbeJumpHereOrPopInst(Vdbe*, int addr);
SQLITE_PRIVATE int sqlite3VdbeChangeToNoop(Vdbe*, int addr);
SQLITE_PRIVATE int sqlite3VdbeDeletePriorOpcode(Vdbe*, u8 op);
#ifdef SQLITE_DEBUG
SQLITE_PRIVATE   void sqlite3VdbeReleaseRegisters(Parse*,int addr, int n, u32 mask, int);
#else
# define sqlite3VdbeReleaseRegisters(P,A,N,M,F)
#endif
SQLITE_PRIVATE void sqlite3VdbeChangeP4(Vdbe*, int addr, const char *zP4, int N);
SQLITE_PRIVATE void sqlite3VdbeAppendP4(Vdbe*, void *pP4, int p4type);
SQLITE_PRIVATE void sqlite3VdbeSetP4KeyInfo(Parse*, Index*);
SQLITE_PRIVATE void sqlite3VdbeUsesBtree(Vdbe*, int);
SQLITE_PRIVATE VdbeOp *sqlite3VdbeGetOp(Vdbe*, int);
SQLITE_PRIVATE VdbeOp *sqlite3VdbeGetLastOp(Vdbe*);
SQLITE_PRIVATE int sqlite3VdbeMakeLabel(Parse*);
SQLITE_PRIVATE void sqlite3VdbeRunOnlyOnce(Vdbe*);
SQLITE_PRIVATE void sqlite3VdbeReusable(Vdbe*);
SQLITE_PRIVATE void sqlite3VdbeDelete(Vdbe*);
SQLITE_PRIVATE void sqlite3VdbeMakeReady(Vdbe*,Parse*);
SQLITE_PRIVATE int sqlite3VdbeFinalize(Vdbe*);
SQLITE_PRIVATE void sqlite3VdbeResolveLabel(Vdbe*, int);

# define VdbeCoverageNeverNullIf(v,x)
# define VdbeCoverageEqNe(v)
# define VDBE_OFFSET_LINENO(x) 0
#endif

#ifdef SQLITE_ENABLE_STMT_SCANSTATUS
SQLITE_PRIVATE void sqlite3VdbeScanStatus(Vdbe*, int, int, int, LogEst, const char*);
SQLITE_PRIVATE void sqlite3VdbeScanStatusRange(Vdbe*, int, int, int);
SQLITE_PRIVATE void sqlite3VdbeScanStatusCounters(Vdbe*, int, int, int);
#else
# define sqlite3VdbeScanStatus(a,b,c,d,e,f)
# define sqlite3VdbeScanStatusRange(a,b,c,d)
# define sqlite3VdbeScanStatusCounters(a,b,c,d)
#endif

#if defined(SQLITE_DEBUG) || defined(VDBE_PROFILE)
SQLITE_PRIVATE void sqlite3VdbePrintOp(FILE*, int, VdbeOp*);
#endif

#endif /* SQLITE_VDBE_H */

#ifdef SQLITE_DIRECT_OVERFLOW_READ
SQLITE_PRIVATE int sqlite3PCacheIsDirty(PCache *pCache);
#endif

#endif /* _PCACHE_H_ */

/************** End of pcache.h **********************************************/



































































































































































































































































































/************** Continuing where we left off in sqliteInt.h ******************/
/************** Include mutex.h in the middle of sqliteInt.h *****************/
/************** Begin file mutex.h *******************************************/
/*
** 2007 August 28
**
** The author disclaims copyright to this source code.  In place of

  LookasideSlot *pSmallInit; /* List of small buffers not prediously used */
  LookasideSlot *pSmallFree; /* List of available small buffers */
  void *pMiddle;          /* First byte past end of full-size buffers and
                          ** the first byte of LOOKASIDE_SMALL buffers */
#endif /* SQLITE_OMIT_TWOSIZE_LOOKASIDE */
  void *pStart;           /* First byte of available memory space */
  void *pEnd;             /* First byte past end of available space */
  void *pTrueEnd;         /* True value of pEnd, when db->pnBytesFreed!=0 */
};
struct LookasideSlot {
  LookasideSlot *pNext;    /* Next buffer in the list of free buffers */
};

#define DisableLookaside  db->lookaside.bDisable++;db->lookaside.sz=0
#define EnableLookaside   db->lookaside.bDisable--;\

   /* TH3 expects this value  ^^^^^^^^^^ to be 0x40000. Coordinate any change */
#define SQLITE_BloomFilter    0x00080000 /* Use a Bloom filter on searches */
#define SQLITE_BloomPulldown  0x00100000 /* Run Bloom filters early */
#define SQLITE_BalancedMerge  0x00200000 /* Balance multi-way merges */
#define SQLITE_ReleaseReg     0x00400000 /* Use OP_ReleaseReg for testing */
#define SQLITE_FlttnUnionAll  0x00800000 /* Disable the UNION ALL flattener */
   /* TH3 expects this value  ^^^^^^^^^^ See flatten04.test */
#define SQLITE_IndexedExpr    0x01000000 /* Pull exprs from index when able */
#define SQLITE_Coroutines     0x02000000 /* Co-routines for subqueries */
#define SQLITE_AllOpts        0xffffffff /* All optimizations */

/*
** Macros for testing whether or not optimizations are enabled or disabled.
*/
#define OptimizationDisabled(db, mask)  (((db)->dbOptFlags&(mask))!=0)
#define OptimizationEnabled(db, mask)   (((db)->dbOptFlags&(mask))==0)

** Value constraints (enforced via assert()):
**     SQLITE_FUNC_MINMAX      ==  NC_MinMaxAgg      == SF_MinMaxAgg
**     SQLITE_FUNC_ANYORDER    ==  NC_OrderAgg       == SF_OrderByReqd
**     SQLITE_FUNC_LENGTH      ==  OPFLAG_LENGTHARG
**     SQLITE_FUNC_TYPEOF      ==  OPFLAG_TYPEOFARG
**     SQLITE_FUNC_CONSTANT    ==  SQLITE_DETERMINISTIC from the API
**     SQLITE_FUNC_DIRECT      ==  SQLITE_DIRECTONLY from the API
**     SQLITE_FUNC_UNSAFE      ==  SQLITE_INNOCUOUS  -- opposite meanings!!!
**     SQLITE_FUNC_ENCMASK   depends on SQLITE_UTF* macros in the API
**
** Note that even though SQLITE_FUNC_UNSAFE and SQLITE_INNOCUOUS have the
** same bit value, their meanings are inverted.  SQLITE_FUNC_UNSAFE is
** used internally and if set means tha the function has side effects.
** SQLITE_INNOCUOUS is used by application code and means "not unsafe".
** See multiple instances of tag-20230109-1.
*/
#define SQLITE_FUNC_ENCMASK  0x0003 /* SQLITE_UTF8, SQLITE_UTF16BE or UTF16LE */
#define SQLITE_FUNC_LIKE     0x0004 /* Candidate for the LIKE optimization */
#define SQLITE_FUNC_CASE     0x0008 /* Case-sensitive LIKE-type function */
#define SQLITE_FUNC_EPHEM    0x0010 /* Ephemeral.  Delete with VDBE */
#define SQLITE_FUNC_NEEDCOLL 0x0020 /* sqlite3GetFuncCollSeq() might be called*/
#define SQLITE_FUNC_LENGTH   0x0040 /* Built-in length() function */

#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, iArg, xFunc) \
  {nArg, SQLITE_FUNC_BUILTIN|SQLITE_DETERMINISTIC|\
   SQLITE_FUNC_CONSTANT|SQLITE_UTF8, \
   SQLITE_INT_TO_PTR(iArg), 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) \

*/
#define SQLITE_AFF_NONE     0x40  /* '@' */
#define SQLITE_AFF_BLOB     0x41  /* 'A' */
#define SQLITE_AFF_TEXT     0x42  /* 'B' */
#define SQLITE_AFF_NUMERIC  0x43  /* 'C' */
#define SQLITE_AFF_INTEGER  0x44  /* 'D' */
#define SQLITE_AFF_REAL     0x45  /* 'E' */
#define SQLITE_AFF_FLEXNUM  0x46  /* 'F' */

#define sqlite3IsNumericAffinity(X)  ((X)>=SQLITE_AFF_NUMERIC)

/*
** The SQLITE_AFF_MASK values masks off the significant bits of an
** affinity value.
*/

** Test to see whether or not a table is a virtual table.  This is
** done as a macro so that it will be optimized out when virtual
** table support is omitted from the build.
*/
#ifndef SQLITE_OMIT_VIRTUALTABLE
#  define IsVirtual(X)      ((X)->eTabType==TABTYP_VTAB)
#  define ExprIsVtab(X)  \
   ((X)->op==TK_COLUMN && (X)->y.pTab->eTabType==TABTYP_VTAB)
#else
#  define IsVirtual(X)      0
#  define ExprIsVtab(X)     0
#endif

/*
** Macros to determine if a column is hidden.  IsOrdinaryHiddenColumn()

** first column to be indexed (c3) has an index of 2 in Ex1.aCol[].
** The second column to be indexed (c1) has an index of 0 in
** Ex1.aCol[], hence Ex2.aiColumn[1]==0.
**
** The Index.onError field determines whether or not the indexed columns
** must be unique and what to do if they are not.  When Index.onError=OE_None,
** it means this is not a unique index.  Otherwise it is a unique index
** and the value of Index.onError indicates which conflict resolution
** algorithm to employ when an attempt is made to insert a non-unique
** element.
**
** The colNotIdxed bitmask is used in combination with SrcItem.colUsed
** for a fast test to see if an index can serve as a covering index.
** colNotIdxed has a 1 bit for every column of the original table that
** is *not* available in the index.  Thus the expression
** "colUsed & colNotIdxed" will be non-zero if the index is not a
** covering index.  The most significant bit of of colNotIdxed will always
** be true (note-20221022-a).  If a column beyond the 63rd column of the
** table is used, the "colUsed & colNotIdxed" test will always be non-zero
** and we have to assume either that the index is not covering, or use
** an alternative (slower) algorithm to determine whether or not
** the index is covering.
**
** While parsing a CREATE TABLE or CREATE INDEX statement in order to
** generate VDBE code (as opposed to parsing one read from an sqlite_schema
** table as part of parsing an existing database schema), transient instances
** of this structure may be created. In this case the Index.tnum variable is
** used to store the address of a VDBE instruction, not a database page
** number (it cannot - the database page is not allocated until the VDBE
** program is executed). See convertToWithoutRowidTable() for details.

  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 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[] */
  int nSampleCol;          /* Size of IndexSample.anEq[] and so on */
  tRowcnt *aAvgEq;         /* Average nEq values for keys not in aSample */
  IndexSample *aSample;    /* Samples of the left-most key */
  tRowcnt *aiRowEst;       /* Non-logarithmic stat1 data for this index */
  tRowcnt nRowEst0;        /* Non-logarithmic number of rows in the index */
#endif
  Bitmask colNotIdxed;     /* Unindexed columns in pTab */
};

/*
** Allowed values for Index.idxType
*/
#define SQLITE_IDXTYPE_APPDEF      0   /* Created using CREATE INDEX */
#define SQLITE_IDXTYPE_UNIQUE      1   /* Implements a UNIQUE constraint */

** fields do not need to be freed when deallocating the AggInfo structure.
*/
struct AggInfo {
  u8 directMode;          /* Direct rendering mode means take data directly
                          ** from source tables rather than from accumulators */
  u8 useSortingIdx;       /* In direct mode, reference the sorting index rather
                          ** than the source table */
  u16 nSortingColumn;     /* Number of columns in the sorting index */
  int sortingIdx;         /* Cursor number of the sorting index */
  int sortingIdxPTab;     /* Cursor number of pseudo-table */

  int iFirstReg;          /* First register in range for aCol[] and aFunc[] */
  ExprList *pGroupBy;     /* The group by clause */
  struct AggInfo_col {    /* For each column used in source tables */
    Table *pTab;             /* Source table */
    Expr *pCExpr;            /* The original expression */
    int iTable;              /* Cursor number of the source table */

    i16 iColumn;             /* Column number within the source table */
    i16 iSorterColumn;       /* Column number in the sorting index */
  } *aCol;
  int nColumn;            /* Number of used entries in aCol[] */
  int nAccumulator;       /* Number of columns that show through to the output.
                          ** Additional columns are used only as parameters to
                          ** aggregate functions */
  struct AggInfo_func {   /* For each aggregate function */
    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 */
  } *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
};

/*
** Macros to compute aCol[] and aFunc[] register numbers.
**
** These macros should not be used prior to the call to
** assignAggregateRegisters() that computes the value of pAggInfo->iFirstReg.
** The assert()s that are part of this macro verify that constraint.
*/
#define AggInfoColumnReg(A,I)  (assert((A)->iFirstReg),(A)->iFirstReg+(I))
#define AggInfoFuncReg(A,I)    \
                      (assert((A)->iFirstReg),(A)->iFirstReg+(A)->nColumn+(I))

/*
** The datatype ynVar is a signed integer, either 16-bit or 32-bit.
** Usually it is 16-bits.  But if SQLITE_MAX_VARIABLE_NUMBER is greater
** than 32767 we have to make it 32-bit.  16-bit is preferred because
** it uses less memory in the Expr object, which is a big memory user
** in systems with lots of prepared statements.  And few applications
** need more than about 10 or 20 variables.  But some extreme users want

#define EP_Commuted   0x000400 /* Comparison operator has been commuted */
#define EP_IntValue   0x000800 /* Integer value contained in u.iValue */
#define EP_xIsSelect  0x001000 /* x.pSelect is valid (otherwise x.pList is) */
#define EP_Skip       0x002000 /* Operator does not contribute to affinity */
#define EP_Reduced    0x004000 /* Expr struct EXPR_REDUCEDSIZE bytes only */
#define EP_Win        0x008000 /* Contains window functions */
#define EP_TokenOnly  0x010000 /* Expr struct EXPR_TOKENONLYSIZE bytes only */
                   /* 0x020000 // Available for reuse */
#define EP_IfNullRow  0x040000 /* The TK_IF_NULL_ROW opcode */
#define EP_Unlikely   0x080000 /* unlikely() or likelihood() function */
#define EP_ConstFunc  0x100000 /* A SQLITE_FUNC_CONSTANT or _SLOCHNG function */
#define EP_CanBeNull  0x200000 /* Can be null despite NOT NULL constraint */
#define EP_Subquery   0x400000 /* Tree contains a TK_SELECT operator */
#define EP_Leaf       0x800000 /* Expr.pLeft, .pRight, .u.pSelect all NULL */
#define EP_WinFunc   0x1000000 /* TK_FUNCTION with Expr.y.pWin set */

#define EU4_IDX    1   /* Uses IdList.a.u4.idx */
#define EU4_EXPR   2   /* Uses IdList.a.u4.pExpr -- NOT CURRENTLY USED */

/*
** The SrcItem object represents a single term in the FROM clause of a query.
** The SrcList object is mostly an array of SrcItems.
**
** The jointype starts out showing the join type between the current table
** and the next table on the list.  The parser builds the list this way.
** But sqlite3SrcListShiftJoinType() later shifts the jointypes so that each
** jointype expresses the join between the table and the previous table.
**
** In the colUsed field, the high-order bit (bit 63) is set if the table
** contains more than 63 columns and the 64-th or later column is used.
**
** Union member validity:
**
**    u1.zIndexedBy          fg.isIndexedBy && !fg.isTabFunc
**    u1.pFuncArg            fg.isTabFunc   && !fg.isIndexedBy
**    u2.pIBIndex            fg.isIndexedBy && !fg.isCte
**    u2.pCteUse             fg.isCte       && !fg.isIndexedBy
*/

    unsigned isNestedFrom :1;  /* pSelect is a SF_NestedFrom subquery */
  } fg;
  int iCursor;      /* The VDBE cursor number used to access this table */
  union {
    Expr *pOn;        /* fg.isUsing==0 =>  The ON clause of a join */
    IdList *pUsing;   /* fg.isUsing==1 =>  The USING clause of a join */
  } u3;
  Bitmask colUsed;  /* Bit N set if column N used. Details above for N>62 */
  union {
    char *zIndexedBy;    /* Identifier from "INDEXED BY <zIndex>" clause */
    ExprList *pFuncArg;  /* Arguments to table-valued-function */
  } u1;
  union {
    Index *pIBIndex;  /* Index structure corresponding to u1.zIndexedBy */
    CteUse *pCteUse;  /* CTE Usage info when fg.isCte is true */
  } u2;
};

/*
** The OnOrUsing object represents either an ON clause or a USING clause.
** It can never be both at the same time, but it can be neither.
*/
struct OnOrUsing {
  Expr *pOn;         /* The ON clause of a join */
  IdList *pUsing;    /* The USING clause of a join */
};

/*
** This object represents one or more tables that are the source of
** content for an SQL statement.  For example, a single SrcList object
** is used to hold the FROM clause of a SELECT statement.  SrcList also





** represents the target tables for DELETE, INSERT, and UPDATE statements.


**







*/
struct SrcList {
  int nSrc;        /* Number of tables or subqueries in the FROM clause */
  u32 nAlloc;      /* Number of entries allocated in a[] below */
  SrcItem a[1];    /* One entry for each identifier on the list */
};

#define SF_View          0x0200000 /* SELECT statement is a view */
#define SF_NoopOrderBy   0x0400000 /* ORDER BY is ignored for this query */
#define SF_UFSrcCheck    0x0800000 /* Check pSrc as required by UPDATE...FROM */
#define SF_PushDown      0x1000000 /* SELECT has be modified by push-down opt */
#define SF_MultiPart     0x2000000 /* Has multiple incompatible PARTITIONs */
#define SF_CopyCte       0x4000000 /* SELECT statement is a copy of a CTE */
#define SF_OrderByReqd   0x8000000 /* The ORDER BY clause may not be omitted */
#define SF_UpdateFrom   0x10000000 /* Query originates with UPDATE FROM */

/* True if S exists and has SF_NestedFrom */
#define IsNestedFrom(S) ((S)!=0 && ((S)->selFlags&SF_NestedFrom)!=0)

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

*/
struct SelectDest {
  u8 eDest;            /* How to dispose of the results.  One of SRT_* above. */
  int iSDParm;         /* A parameter used by the eDest disposal method */
  int iSDParm2;        /* A second parameter for the eDest disposal method */
  int iSdst;           /* Base register where results are written */
  int nSdst;           /* Number of registers allocated */
  char *zAffSdst;      /* Affinity used for SRT_Set */
  ExprList *pOrderBy;  /* Key columns for SRT_Queue and SRT_DistQueue */
};

/*
** During code generation of statements that do inserts into AUTOINCREMENT
** tables, the following information is attached to the Table.u.autoInc.p
** pointer of each autoincrement table to record some side information that

# define DbMaskZero(M)      memset((M),0,sizeof(M))
# define DbMaskSet(M,I)     (M)[(I)/8]|=(1<<((I)&7))
# define DbMaskAllZero(M)   sqlite3DbMaskAllZero(M)
# define DbMaskNonZero(M)   (sqlite3DbMaskAllZero(M)==0)
#else
  typedef unsigned int yDbMask;
# define DbMaskTest(M,I)    (((M)&(((yDbMask)1)<<(I)))!=0)
# define DbMaskZero(M)      ((M)=0)
# define DbMaskSet(M,I)     ((M)|=(((yDbMask)1)<<(I)))
# define DbMaskAllZero(M)   ((M)==0)
# define DbMaskNonZero(M)   ((M)!=0)
#endif

/*
** For each index X that has as one of its arguments either an expression
** or the name of a virtual generated column, and if X is in scope such that
** the value of the expression can simply be read from the index, then
** there is an instance of this object on the Parse.pIdxExpr list.
**
** During code generation, while generating code to evaluate expressions,
** this list is consulted and if a matching expression is found, the value
** is read from the index rather than being recomputed.
*/
struct IndexedExpr {
  Expr *pExpr;            /* The expression contained in the index */
  int iDataCur;           /* The data cursor associated with the index */
  int iIdxCur;            /* The index cursor */
  int iIdxCol;            /* The index column that contains value of pExpr */
  u8 bMaybeNullRow;       /* True if we need an OP_IfNullRow check */
  IndexedExpr *pIENext;   /* Next in a list of all indexed expressions */
#ifdef SQLITE_ENABLE_EXPLAIN_COMMENTS
  const char *zIdxName;   /* Name of index, used only for bytecode comments */
#endif
};

/*
** An instance of the ParseCleanup object specifies an operation that
** should be performed after parsing to deallocation resources obtained
** during the parse and which are no longer needed.
*/
struct ParseCleanup {

  u8 nested;           /* Number of nested calls to the parser/code generator */
  u8 nTempReg;         /* Number of temporary registers in aTempReg[] */
  u8 isMultiWrite;     /* True if statement may modify/insert multiple rows */
  u8 mayAbort;         /* True if statement may throw an ABORT exception */
  u8 hasCompound;      /* Need to invoke convertCompoundSelectToSubquery() */
  u8 okConstFactor;    /* OK to factor out constants */
  u8 disableLookaside; /* Number of times lookaside has been disabled */
  u8 prepFlags;        /* SQLITE_PREPARE_* flags */
  u8 withinRJSubrtn;   /* Nesting level for RIGHT JOIN body subroutines */
#if defined(SQLITE_DEBUG) || defined(SQLITE_COVERAGE_TEST)
  u8 earlyCleanup;     /* OOM inside sqlite3ParserAddCleanup() */
#endif
  int nRangeReg;       /* Size of the temporary register block */
  int iRangeReg;       /* First register in temporary register block */
  int nErr;            /* Number of errors seen */
  int nTab;            /* Number of previously allocated VDBE cursors */
  int nMem;            /* Number of memory cells used so far */
  int szOpAlloc;       /* Bytes of memory space allocated for Vdbe.aOp[] */
  int iSelfTab;        /* Table associated with an index on expr, or negative
                       ** of the base register during check-constraint eval */
  int nLabel;          /* The *negative* of the number of labels used */
  int nLabelAlloc;     /* Number of slots in aLabel */
  int *aLabel;         /* Space to hold the labels */
  ExprList *pConstExpr;/* Constant expressions */
  IndexedExpr *pIdxEpr;/* List of expressions used by active indexes */
  Token constraintName;/* Name of the constraint currently being parsed */
  yDbMask writeMask;   /* Start a write transaction on these databases */
  yDbMask cookieMask;  /* Bitmask of schema verified databases */
  int regRowid;        /* Register holding rowid of CREATE TABLE entry */
  int regRoot;         /* Register holding root page number for new objects */
  int nMaxArg;         /* Max args passed to user function by sub-program */
  int nSelect;         /* Number of SELECT stmts. Counter for Select.selId */

  union {
    int addrCrTab;         /* Address of OP_CreateBtree on CREATE TABLE */
    Returning *pReturning; /* The RETURNING clause */
  } u1;
  u32 nQueryLoop;      /* Est number of iterations of a query (10*log2(N)) */
  u32 oldmask;         /* Mask of old.* columns referenced */
  u32 newmask;         /* Mask of new.* columns referenced */
#ifndef SQLITE_OMIT_PROGRESS_CALLBACK
  u32 nProgressSteps;  /* xProgress steps taken during sqlite3_prepare() */
#endif
  u8 eTriggerOp;       /* TK_UPDATE, TK_INSERT or TK_DELETE */
  u8 bReturning;       /* Coding a RETURNING trigger */
  u8 eOrconf;          /* Default ON CONFLICT policy for trigger steps */
  u8 disableTriggers;  /* True to disable triggers */

  /**************************************************************************
  ** Fields above must be initialized to zero.  The fields that follow,

    int n;                                    /* A counter */
    int iCur;                                 /* A cursor number */
    SrcList *pSrcList;                        /* FROM clause */
    struct CCurHint *pCCurHint;               /* Used by codeCursorHint() */
    struct RefSrcList *pRefSrcList;           /* sqlite3ReferencesSrcList() */
    int *aiCol;                               /* array of column indexes */
    struct IdxCover *pIdxCover;               /* Check for index coverage */

    ExprList *pGroupBy;                       /* GROUP BY clause */
    Select *pSelect;                          /* HAVING to WHERE clause ctx */
    struct WindowRewrite *pRewrite;           /* Window rewrite context */
    struct WhereConst *pConst;                /* WHERE clause constants */
    struct RenameCtx *pRename;                /* RENAME COLUMN context */
    struct Table *pTab;                       /* Table of generated column */
    struct CoveringIndexCheck *pCovIdxCk;     /* Check for covering index */
    SrcItem *pSrcItem;                        /* A single FROM clause item */
    DbFixer *pFix;                            /* See sqlite3FixSelect() */
  } u;
};

/*
** The following structure contains information used by the sqliteFix...
** routines as they walk the parse tree to make database references
** explicit.

SQLITE_PRIVATE char *sqlite3DbStrNDup(sqlite3*,const char*, u64);
SQLITE_PRIVATE char *sqlite3DbSpanDup(sqlite3*,const char*,const char*);
SQLITE_PRIVATE void *sqlite3Realloc(void*, u64);
SQLITE_PRIVATE void *sqlite3DbReallocOrFree(sqlite3 *, void *, u64);
SQLITE_PRIVATE void *sqlite3DbRealloc(sqlite3 *, void *, u64);
SQLITE_PRIVATE void sqlite3DbFree(sqlite3*, void*);
SQLITE_PRIVATE void sqlite3DbFreeNN(sqlite3*, void*);
SQLITE_PRIVATE void sqlite3DbNNFreeNN(sqlite3*, void*);
SQLITE_PRIVATE int sqlite3MallocSize(const void*);
SQLITE_PRIVATE int sqlite3DbMallocSize(sqlite3*, const void*);
SQLITE_PRIVATE void *sqlite3PageMalloc(int);
SQLITE_PRIVATE void sqlite3PageFree(void*);
SQLITE_PRIVATE void sqlite3MemSetDefault(void);
#ifndef SQLITE_UNTESTABLE
SQLITE_PRIVATE void sqlite3BenignMallocHooks(void (*)(void), void (*)(void));
#endif
SQLITE_PRIVATE int sqlite3HeapNearlyFull(void);

/*
** On systems with ample stack space and that support alloca(), make
** use of alloca() to obtain space for large automatic objects.  By default,
** obtain space from malloc().
**
** The alloca() routine never returns NULL.  This will cause code paths
** that deal with sqlite3StackAlloc() failures to be unreachable.
*/
#ifdef SQLITE_USE_ALLOCA
# define sqlite3StackAllocRaw(D,N)   alloca(N)
# define sqlite3StackAllocRawNN(D,N) alloca(N)
# define sqlite3StackFree(D,P)
# define sqlite3StackFreeNN(D,P)
#else
# define sqlite3StackAllocRaw(D,N)   sqlite3DbMallocRaw(D,N)
# define sqlite3StackAllocRawNN(D,N) sqlite3DbMallocRawNN(D,N)
# define sqlite3StackFree(D,P)       sqlite3DbFree(D,P)
# define sqlite3StackFreeNN(D,P)     sqlite3DbFreeNN(D,P)
#endif

/* Do not allow both MEMSYS5 and MEMSYS3 to be defined together.  If they
** are, disable MEMSYS3
*/
#ifdef SQLITE_ENABLE_MEMSYS5
SQLITE_PRIVATE const sqlite3_mem_methods *sqlite3MemGetMemsys5(void);

SQLITE_PRIVATE   void sqlite3TreeViewBareIdList(TreeView*, const IdList*, const char*);
SQLITE_PRIVATE   void sqlite3TreeViewIdList(TreeView*, const IdList*, u8, const char*);
SQLITE_PRIVATE   void sqlite3TreeViewColumnList(TreeView*, const Column*, int, u8);
SQLITE_PRIVATE   void sqlite3TreeViewSrcList(TreeView*, const SrcList*);
SQLITE_PRIVATE   void sqlite3TreeViewSelect(TreeView*, const Select*, u8);
SQLITE_PRIVATE   void sqlite3TreeViewWith(TreeView*, const With*, u8);
SQLITE_PRIVATE   void sqlite3TreeViewUpsert(TreeView*, const Upsert*, u8);
#if TREETRACE_ENABLED
SQLITE_PRIVATE   void sqlite3TreeViewDelete(const With*, const SrcList*, const Expr*,
                             const ExprList*,const Expr*, const Trigger*);
SQLITE_PRIVATE   void sqlite3TreeViewInsert(const With*, const SrcList*,
                             const IdList*, const Select*, const ExprList*,
                             int, const Upsert*, const Trigger*);
SQLITE_PRIVATE   void sqlite3TreeViewUpdate(const With*, const SrcList*, const ExprList*,
                             const Expr*, int, const ExprList*, const Expr*,
                             const Upsert*, const Trigger*);
#endif
#ifndef SQLITE_OMIT_TRIGGER
SQLITE_PRIVATE   void sqlite3TreeViewTriggerStep(TreeView*, const TriggerStep*, u8, u8);
SQLITE_PRIVATE   void sqlite3TreeViewTrigger(TreeView*, const Trigger*, u8, u8);
#endif
#ifndef SQLITE_OMIT_WINDOWFUNC
SQLITE_PRIVATE   void sqlite3TreeViewWindow(TreeView*, const Window*, u8);
SQLITE_PRIVATE   void sqlite3TreeViewWinFunc(TreeView*, const Window*, u8);

#ifndef SQLITE_OMIT_WINDOWFUNC
SQLITE_PRIVATE   void sqlite3ShowWindow(const Window*);
SQLITE_PRIVATE   void sqlite3ShowWinFunc(const Window*);
#endif
#endif

SQLITE_PRIVATE void sqlite3SetString(char **, sqlite3*, const char*);
SQLITE_PRIVATE void sqlite3ProgressCheck(Parse*);
SQLITE_PRIVATE void sqlite3ErrorMsg(Parse*, const char*, ...);
SQLITE_PRIVATE int sqlite3ErrorToParser(sqlite3*,int);
SQLITE_PRIVATE void sqlite3Dequote(char*);
SQLITE_PRIVATE void sqlite3DequoteExpr(Expr*);
SQLITE_PRIVATE void sqlite3DequoteToken(Token*);
SQLITE_PRIVATE void sqlite3TokenInit(Token*,char*);
SQLITE_PRIVATE int sqlite3KeywordCode(const unsigned char*, int);

SQLITE_PRIVATE void sqlite3ColumnSetExpr(Parse*,Table*,Column*,Expr*);
SQLITE_PRIVATE Expr *sqlite3ColumnExpr(Table*,Column*);
SQLITE_PRIVATE void sqlite3ColumnSetColl(sqlite3*,Column*,const char*zColl);
SQLITE_PRIVATE const char *sqlite3ColumnColl(Column*);
SQLITE_PRIVATE void sqlite3DeleteColumnNames(sqlite3*,Table*);
SQLITE_PRIVATE void sqlite3GenerateColumnNames(Parse *pParse, Select *pSelect);
SQLITE_PRIVATE int sqlite3ColumnsFromExprList(Parse*,ExprList*,i16*,Column**);
SQLITE_PRIVATE void sqlite3SubqueryColumnTypes(Parse*,Table*,Select*,char);
SQLITE_PRIVATE Table *sqlite3ResultSetOfSelect(Parse*,Select*,char);
SQLITE_PRIVATE void sqlite3OpenSchemaTable(Parse *, int);
SQLITE_PRIVATE Index *sqlite3PrimaryKeyIndex(Table*);
SQLITE_PRIVATE i16 sqlite3TableColumnToIndex(Index*, i16);
#ifdef SQLITE_OMIT_GENERATED_COLUMNS
# define sqlite3TableColumnToStorage(T,X) (X)  /* No-op pass-through */
# define sqlite3StorageColumnToTable(T,X) (X)  /* No-op pass-through */

SQLITE_PRIVATE void sqlite3Detach(Parse*, Expr*);
SQLITE_PRIVATE void sqlite3FixInit(DbFixer*, Parse*, int, const char*, const Token*);
SQLITE_PRIVATE int sqlite3FixSrcList(DbFixer*, SrcList*);
SQLITE_PRIVATE int sqlite3FixSelect(DbFixer*, Select*);
SQLITE_PRIVATE int sqlite3FixExpr(DbFixer*, Expr*);
SQLITE_PRIVATE int sqlite3FixTriggerStep(DbFixer*, TriggerStep*);
SQLITE_PRIVATE int sqlite3RealSameAsInt(double,sqlite3_int64);
SQLITE_PRIVATE i64 sqlite3RealToI64(double);
SQLITE_PRIVATE int sqlite3Int64ToText(i64,char*);
SQLITE_PRIVATE int sqlite3AtoF(const char *z, double*, int, u8);
SQLITE_PRIVATE int sqlite3GetInt32(const char *, int*);
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

  (u8)(((u32)(B)<(u32)0x80)?(*(A)=(unsigned char)(B)),1:\
  sqlite3PutVarint((A),(B)))
#define getVarint    sqlite3GetVarint
#define putVarint    sqlite3PutVarint


SQLITE_PRIVATE const char *sqlite3IndexAffinityStr(sqlite3*, Index*);
SQLITE_PRIVATE char *sqlite3TableAffinityStr(sqlite3*,const Table*);
SQLITE_PRIVATE void sqlite3TableAffinity(Vdbe*, Table*, int);
SQLITE_PRIVATE char sqlite3CompareAffinity(const Expr *pExpr, char aff2);
SQLITE_PRIVATE int sqlite3IndexAffinityOk(const Expr *pExpr, char idx_affinity);
SQLITE_PRIVATE char sqlite3TableColumnAffinity(const Table*,int);
SQLITE_PRIVATE char sqlite3ExprAffinity(const Expr *pExpr);
SQLITE_PRIVATE int sqlite3ExprDataType(const Expr *pExpr);
SQLITE_PRIVATE int sqlite3Atoi64(const char*, i64*, int, u8);
SQLITE_PRIVATE int sqlite3DecOrHexToI64(const char*, i64*);
SQLITE_PRIVATE void sqlite3ErrorWithMsg(sqlite3*, int, const char*,...);
SQLITE_PRIVATE void sqlite3Error(sqlite3*,int);
SQLITE_PRIVATE void sqlite3ErrorClear(sqlite3*);
SQLITE_PRIVATE void sqlite3SystemError(sqlite3*,int);
SQLITE_PRIVATE void *sqlite3HexToBlob(sqlite3*, const char *z, int n);
SQLITE_PRIVATE u8 sqlite3HexToInt(int h);
SQLITE_PRIVATE int sqlite3TwoPartName(Parse *, Token *, Token *, Token **);

#if defined(SQLITE_NEED_ERR_NAME)
SQLITE_PRIVATE const char *sqlite3ErrName(int);
#endif

#ifndef SQLITE_OMIT_DESERIALIZE
SQLITE_PRIVATE int sqlite3MemdbInit(void);
SQLITE_PRIVATE int sqlite3IsMemdb(const sqlite3_vfs*);
#else
# define sqlite3IsMemdb(X) 0
#endif

SQLITE_PRIVATE const char *sqlite3ErrStr(int);
SQLITE_PRIVATE int sqlite3ReadSchema(Parse *pParse);
SQLITE_PRIVATE CollSeq *sqlite3FindCollSeq(sqlite3*,u8 enc, const char*,int);
SQLITE_PRIVATE int sqlite3IsBinary(const CollSeq*);
SQLITE_PRIVATE CollSeq *sqlite3LocateCollSeq(Parse *pParse, const char*zName);

SQLITE_PRIVATE int sqlite3ValueFromExpr(sqlite3 *, const Expr *, u8, u8, sqlite3_value **);
SQLITE_PRIVATE void sqlite3ValueApplyAffinity(sqlite3_value *, u8, u8);
#ifndef SQLITE_AMALGAMATION
SQLITE_PRIVATE const unsigned char sqlite3OpcodeProperty[];
SQLITE_PRIVATE const char sqlite3StrBINARY[];
SQLITE_PRIVATE const unsigned char sqlite3StdTypeLen[];
SQLITE_PRIVATE const char sqlite3StdTypeAffinity[];

SQLITE_PRIVATE const char *sqlite3StdType[];
SQLITE_PRIVATE const unsigned char sqlite3UpperToLower[];
SQLITE_PRIVATE const unsigned char *sqlite3aLTb;
SQLITE_PRIVATE const unsigned char *sqlite3aEQb;
SQLITE_PRIVATE const unsigned char *sqlite3aGTb;
SQLITE_PRIVATE const unsigned char sqlite3CtypeMap[];
SQLITE_PRIVATE SQLITE_WSD struct Sqlite3Config sqlite3Config;

SQLITE_PRIVATE void sqlite3NoopDestructor(void*);
SQLITE_PRIVATE void *sqlite3OomFault(sqlite3*);
SQLITE_PRIVATE void sqlite3OomClear(sqlite3*);
SQLITE_PRIVATE int sqlite3ApiExit(sqlite3 *db, int);
SQLITE_PRIVATE int sqlite3OpenTempDatabase(Parse *);

SQLITE_PRIVATE void sqlite3StrAccumInit(StrAccum*, sqlite3*, char*, int, int);
SQLITE_PRIVATE int sqlite3StrAccumEnlarge(StrAccum*, i64);
SQLITE_PRIVATE char *sqlite3StrAccumFinish(StrAccum*);
SQLITE_PRIVATE void sqlite3StrAccumSetError(StrAccum*, u8);
SQLITE_PRIVATE void sqlite3ResultStrAccum(sqlite3_context*,StrAccum*);
SQLITE_PRIVATE void sqlite3SelectDestInit(SelectDest*,int,int);
SQLITE_PRIVATE Expr *sqlite3CreateColumnExpr(sqlite3 *, SrcList *, int, int);
SQLITE_PRIVATE void sqlite3RecordErrorByteOffset(sqlite3*,const char*);
SQLITE_PRIVATE void sqlite3RecordErrorOffsetOfExpr(sqlite3*,const Expr*);

SQLITE_PRIVATE Expr *sqlite3ExprForVectorField(Parse*,Expr*,int,int);
SQLITE_PRIVATE void sqlite3VectorErrorMsg(Parse*, Expr*);

#ifndef SQLITE_OMIT_COMPILEOPTION_DIAGS
SQLITE_PRIVATE const char **sqlite3CompileOptions(int *pnOpt);
#endif

#if SQLITE_OS_UNIX && defined(SQLITE_OS_KV_OPTIONAL)
SQLITE_PRIVATE int sqlite3KvvfsInit(void);
#endif

#if defined(VDBE_PROFILE) \
 || defined(SQLITE_PERFORMANCE_TRACE) \
 || defined(SQLITE_ENABLE_STMT_SCANSTATUS)
SQLITE_PRIVATE sqlite3_uint64 sqlite3Hwtime(void);
#endif

#endif /* SQLITEINT_H */

/************** End of sqliteInt.h *******************************************/
/************** Begin file os_common.h ***************************************/
/*
** 2004 May 22
**

/*
** Macros for performance tracing.  Normally turned off.  Only works
** on i486 hardware.
*/
#ifdef SQLITE_PERFORMANCE_TRACE
































































































static sqlite_uint64 g_start;
static sqlite_uint64 g_elapsed;
#define TIMER_START       g_start=sqlite3Hwtime()
#define TIMER_END         g_elapsed=sqlite3Hwtime()-g_start
#define TIMER_ELAPSED     g_elapsed
#else
#define TIMER_START

#ifndef SQLITE_OMIT_COMPILEOPTION_DIAGS /* IMP: R-16824-07538 */

/*
** Include the configuration header output by 'configure' if we're using the
** autoconf-based build
*/
#if defined(_HAVE_SQLITE_CONFIG_H) && !defined(SQLITECONFIG_H)
/* #include "sqlite_cfg.h" */
#define SQLITECONFIG_H 1
#endif

/* These macros are provided to "stringify" the value of the define
** for those options in which the value is meaningful. */
#define CTIMEOPT_VAL_(opt) #opt
#define CTIMEOPT_VAL(opt) CTIMEOPT_VAL_(opt)

#endif
#ifdef SQLITE_DISABLE_PAGECACHE_OVERFLOW_STATS
  "DISABLE_PAGECACHE_OVERFLOW_STATS",
#endif
#ifdef SQLITE_DISABLE_SKIPAHEAD_DISTINCT
  "DISABLE_SKIPAHEAD_DISTINCT",
#endif
#ifdef SQLITE_DQS
  "DQS=" CTIMEOPT_VAL(SQLITE_DQS),
#endif
#ifdef SQLITE_ENABLE_8_3_NAMES
  "ENABLE_8_3_NAMES=" CTIMEOPT_VAL(SQLITE_ENABLE_8_3_NAMES),
#endif
#ifdef SQLITE_ENABLE_API_ARMOR
  "ENABLE_API_ARMOR",
#endif
#ifdef SQLITE_ENABLE_ATOMIC_WRITE

  "OMIT_WAL",
#endif
#ifdef SQLITE_OMIT_WSD
  "OMIT_WSD",
#endif
#ifdef SQLITE_OMIT_XFER_OPT
  "OMIT_XFER_OPT",



#endif
#ifdef SQLITE_PERFORMANCE_TRACE
  "PERFORMANCE_TRACE",
#endif
#ifdef SQLITE_POWERSAFE_OVERWRITE
# if SQLITE_POWERSAFE_OVERWRITE != 1
  "POWERSAFE_OVERWRITE=" CTIMEOPT_VAL(SQLITE_POWERSAFE_OVERWRITE),

**    sqlite3StdType[]            The actual names of the datatypes.
**
**    sqlite3StdTypeLen[]         The length (in bytes) of each entry
**                                in sqlite3StdType[].
**
**    sqlite3StdTypeAffinity[]    The affinity associated with each entry
**                                in sqlite3StdType[].




*/
SQLITE_PRIVATE const unsigned char sqlite3StdTypeLen[] = { 3, 4, 3, 7, 4, 4 };
SQLITE_PRIVATE const char sqlite3StdTypeAffinity[] = {
  SQLITE_AFF_NUMERIC,
  SQLITE_AFF_BLOB,
  SQLITE_AFF_INTEGER,
  SQLITE_AFF_INTEGER,
  SQLITE_AFF_REAL,
  SQLITE_AFF_TEXT








};
SQLITE_PRIVATE const char *sqlite3StdType[] = {
  "ANY",
  "BLOB",
  "INT",
  "INTEGER",
  "REAL",

** set to NULL if the currently executing frame is the main program.
*/
typedef struct VdbeFrame VdbeFrame;
struct VdbeFrame {
  Vdbe *v;                /* VM this frame belongs to */
  VdbeFrame *pParent;     /* Parent of this frame, or NULL if parent is main */
  Op *aOp;                /* Program instructions for parent frame */

  Mem *aMem;              /* Array of memory cells for parent frame */
  VdbeCursor **apCsr;     /* Array of Vdbe cursors for parent frame */
  u8 *aOnce;              /* Bitmask used by OP_Once */
  void *token;            /* Copy of SubProgram.token */
  i64 lastRowid;          /* Last insert rowid (sqlite3.lastRowid) */
  AuxData *pAuxData;      /* Linked list of auxdata allocations */
#if SQLITE_DEBUG

/* A bitfield type for use inside of structures.  Always follow with :N where
** N is the number of bits.
*/
typedef unsigned bft;  /* Bit Field Type */

/* The ScanStatus object holds a single value for the
** sqlite3_stmt_scanstatus() interface.
**
** aAddrRange[]:
**   This array is used by ScanStatus elements associated with EQP
**   notes that make an SQLITE_SCANSTAT_NCYCLE value available. It is
**   an array of up to 3 ranges of VM addresses for which the Vdbe.anCycle[]
**   values should be summed to calculate the NCYCLE value. Each pair of
**   integer addresses is a start and end address (both inclusive) for a range
**   instructions. A start value of 0 indicates an empty range.
*/
typedef struct ScanStatus ScanStatus;
struct ScanStatus {
  int addrExplain;                /* OP_Explain for loop */
  int aAddrRange[6];
  int addrLoop;                   /* Address of "loops" counter */
  int addrVisit;                  /* Address of "rows visited" counter */
  int iSelectID;                  /* The "Select-ID" for this loop */
  LogEst nEst;                    /* Estimated output rows per loop */
  char *zName;                    /* Name of table or index */
};

** state of the virtual machine.
**
** The "sqlite3_stmt" structure pointer that is returned by sqlite3_prepare()
** is really a pointer to an instance of this structure.
*/
struct Vdbe {
  sqlite3 *db;            /* The database connection that owns this statement */
  Vdbe **ppVPrev,*pVNext; /* Linked list of VDBEs with the same Vdbe.db */
  Parse *pParse;          /* Parsing context used to create this Vdbe */
  ynVar nVar;             /* Number of entries in aVar[] */
  int nMem;               /* Number of memory locations currently allocated */
  int nCursor;            /* Number of slots in apCsr[] */
  u32 cacheCtr;           /* VdbeCursor row cache generation counter */
  int pc;                 /* The program counter */
  int rc;                 /* Value to return */

  /* When allocating a new Vdbe object, all of the fields below should be
  ** initialized to zero or NULL */

  Op *aOp;                /* Space to hold the virtual machine's program */
  int nOp;                /* Number of instructions in the program */
  int nOpAlloc;           /* Slots allocated for aOp[] */
  Mem *aColName;          /* Column names to return */
  Mem *pResultRow;        /* Current output row */
  char *zErrMsg;          /* Error message written here */
  VList *pVList;          /* Name of variables */
#ifndef SQLITE_OMIT_TRACE
  i64 startTime;          /* Time when query started - used for profiling */
#endif
#ifdef SQLITE_DEBUG
  int rcApp;              /* errcode set by sqlite3_result_error_code() */

  VdbeFrame *pFrame;      /* Parent frame */
  VdbeFrame *pDelFrame;   /* List of frame objects to free on VM reset */
  int nFrame;             /* Number of frames in pFrame list */
  u32 expmask;            /* Binding to these vars invalidates VM */
  SubProgram *pProgram;   /* Linked list of all sub-programs used by VM */
  AuxData *pAuxData;      /* Linked list of auxdata allocations */
#ifdef SQLITE_ENABLE_STMT_SCANSTATUS

  int nScan;              /* Entries in aScan[] */
  ScanStatus *aScan;      /* Scan definitions for sqlite3_stmt_scanstatus() */
#endif
};

/*
** The following are allowed values for Vdbe.eVdbeState

SQLITE_PRIVATE void sqlite3VdbeSorterClose(sqlite3 *, VdbeCursor *);
SQLITE_PRIVATE int sqlite3VdbeSorterRowkey(const VdbeCursor *, Mem *);
SQLITE_PRIVATE int sqlite3VdbeSorterNext(sqlite3 *, const VdbeCursor *);
SQLITE_PRIVATE int sqlite3VdbeSorterRewind(const VdbeCursor *, int *);
SQLITE_PRIVATE int sqlite3VdbeSorterWrite(const VdbeCursor *, Mem *);
SQLITE_PRIVATE int sqlite3VdbeSorterCompare(const VdbeCursor *, Mem *, int, int *);

SQLITE_PRIVATE void sqlite3VdbeValueListFree(void*);

#ifdef SQLITE_DEBUG
SQLITE_PRIVATE   void sqlite3VdbeIncrWriteCounter(Vdbe*, VdbeCursor*);
SQLITE_PRIVATE   void sqlite3VdbeAssertAbortable(Vdbe*);
#else
# define sqlite3VdbeIncrWriteCounter(V,C)
# define sqlite3VdbeAssertAbortable(V)
#endif

    */
    case SQLITE_DBSTATUS_SCHEMA_USED: {
      int i;                      /* Used to iterate through schemas */
      int nByte = 0;              /* Used to accumulate return value */

      sqlite3BtreeEnterAll(db);
      db->pnBytesFreed = &nByte;
      assert( db->lookaside.pEnd==db->lookaside.pTrueEnd );
      db->lookaside.pEnd = db->lookaside.pStart;
      for(i=0; i<db->nDb; i++){
        Schema *pSchema = db->aDb[i].pSchema;
        if( ALWAYS(pSchema!=0) ){
          HashElem *p;

          nByte += sqlite3GlobalConfig.m.xRoundup(sizeof(HashElem)) * (
              pSchema->tblHash.count

          }
          for(p=sqliteHashFirst(&pSchema->tblHash); p; p=sqliteHashNext(p)){
            sqlite3DeleteTable(db, (Table *)sqliteHashData(p));
          }
        }
      }
      db->pnBytesFreed = 0;
      db->lookaside.pEnd = db->lookaside.pTrueEnd;
      sqlite3BtreeLeaveAll(db);

      *pHighwater = 0;
      *pCurrent = nByte;
      break;
    }

    /*
    ** *pCurrent gets an accurate estimate of the amount of memory used
    ** to store all prepared statements.
    ** *pHighwater is set to zero.
    */
    case SQLITE_DBSTATUS_STMT_USED: {
      struct Vdbe *pVdbe;         /* Used to iterate through VMs */
      int nByte = 0;              /* Used to accumulate return value */

      db->pnBytesFreed = &nByte;
      assert( db->lookaside.pEnd==db->lookaside.pTrueEnd );
      db->lookaside.pEnd = db->lookaside.pStart;
      for(pVdbe=db->pVdbe; pVdbe; pVdbe=pVdbe->pVNext){
        sqlite3VdbeDelete(pVdbe);
      }
      db->lookaside.pEnd = db->lookaside.pTrueEnd;
      db->pnBytesFreed = 0;

      *pHighwater = 0;  /* IMP: R-64479-57858 */
      *pCurrent = nByte;

      break;
    }

  A = Y/100;
  B = 2 - A + (A/4);
  X1 = 36525*(Y+4716)/100;
  X2 = 306001*(M+1)/10000;
  p->iJD = (sqlite3_int64)((X1 + X2 + D + B - 1524.5 ) * 86400000);
  p->validJD = 1;
  if( p->validHMS ){
    p->iJD += p->h*3600000 + p->m*60000 + (sqlite3_int64)(p->s*1000 + 0.5);
    if( p->validTZ ){
      p->iJD -= p->tz*60000;
      p->validYMD = 0;
      p->validHMS = 0;
      p->validTZ = 0;
    }
  }

      **
      ** Move the date to the same time on the next occurrence of
      ** weekday N where 0==Sunday, 1==Monday, and so forth.  If the
      ** date is already on the appropriate weekday, this is a no-op.
      */
      if( sqlite3_strnicmp(z, "weekday ", 8)==0
               && sqlite3AtoF(&z[8], &r, sqlite3Strlen30(&z[8]), SQLITE_UTF8)>0
               && r>=0.0 && r<7.0 && (n=(int)r)==r ){
        sqlite3_int64 Z;
        computeYMD_HMS(p);
        p->validTZ = 0;
        p->validJD = 0;
        computeJD(p);
        Z = ((p->iJD + 129600000)/86400000) % 7;
        if( Z>n ) Z -= 7;

}
SQLITE_PRIVATE int sqlite3OsFileSize(sqlite3_file *id, i64 *pSize){
  DO_OS_MALLOC_TEST(id);
  return id->pMethods->xFileSize(id, pSize);
}
SQLITE_PRIVATE int sqlite3OsLock(sqlite3_file *id, int lockType){
  DO_OS_MALLOC_TEST(id);
  assert( lockType>=SQLITE_LOCK_SHARED && lockType<=SQLITE_LOCK_EXCLUSIVE );
  return id->pMethods->xLock(id, lockType);
}
SQLITE_PRIVATE int sqlite3OsUnlock(sqlite3_file *id, int lockType){
  assert( lockType==SQLITE_LOCK_NONE || lockType==SQLITE_LOCK_SHARED );
  return id->pMethods->xUnlock(id, lockType);
}
SQLITE_PRIVATE int sqlite3OsCheckReservedLock(sqlite3_file *id, int *pResOut){
  DO_OS_MALLOC_TEST(id);
  return id->pMethods->xCheckReservedLock(id, pResOut);
}

){
  int rc;
  DO_OS_MALLOC_TEST(0);
  /* 0x87f7f is a mask of SQLITE_OPEN_ flags that are valid to be passed
  ** down into the VFS layer.  Some SQLITE_OPEN_ flags (for example,
  ** SQLITE_OPEN_FULLMUTEX or SQLITE_OPEN_SHAREDCACHE) are blocked before
  ** reaching the VFS. */
  assert( zPath || (flags & SQLITE_OPEN_EXCLUSIVE) );
  rc = pVfs->xOpen(pVfs, zPath, pFile, flags & 0x1087f7f, pFlagsOut);
  assert( rc==SQLITE_OK || pFile->pMethods==0 );
  return rc;
}
SQLITE_PRIVATE int sqlite3OsDelete(sqlite3_vfs *pVfs, const char *zPath, int dirSync){
  DO_OS_MALLOC_TEST(0);
  assert( dirSync==0 || dirSync==1 );

*/
static int memsys5Roundup(int n){
  int iFullSz;
  if( n<=mem5.szAtom*2 ){
    if( n<=mem5.szAtom ) return mem5.szAtom;
    return mem5.szAtom*2;
  }
  if( n>0x10000000 ){
    if( n>0x40000000 ) return 0;
    if( n>0x20000000 ) return 0x40000000;
    return 0x20000000;
  }
  for(iFullSz=mem5.szAtom*8; iFullSz<n; iFullSz *= 4);
  if( (iFullSz/2)>=(i64)n ) return iFullSz/2;
  return iFullSz;
}

/*
** Return the ceiling of the logarithm base 2 of iValue.
**
** Examples:   memsys5Log(1) -> 0

    nFull = sqlite3MallocSize(p);
    sqlite3StatusUp(SQLITE_STATUS_MEMORY_USED, nFull);
    sqlite3StatusUp(SQLITE_STATUS_MALLOC_COUNT, 1);
  }
  *pp = p;
}

/*
** Maximum size of any single memory allocation.
**
** This is not a limit on the total amount of memory used.  This is
** a limit on the size parameter to sqlite3_malloc() and sqlite3_realloc().
**
** The upper bound is slightly less than 2GiB:  0x7ffffeff == 2,147,483,391
** This provides a 256-byte safety margin for defense against 32-bit
** signed integer overflow bugs when computing memory allocation sizes.
** Paranoid applications might want to reduce the maximum allocation size
** further for an even larger safety margin.  0x3fffffff or 0x0fffffff
** or even smaller would be reasonable upper bounds on the size of a memory
** allocations for most applications.
*/
#ifndef SQLITE_MAX_ALLOCATION_SIZE
# define SQLITE_MAX_ALLOCATION_SIZE  2147483391
#endif
#if SQLITE_MAX_ALLOCATION_SIZE>2147483391
# error Maximum size for SQLITE_MAX_ALLOCATION_SIZE is 2147483391
#endif

/*
** Allocate memory.  This routine is like sqlite3_malloc() except that it
** assumes the memory subsystem has already been initialized.
*/
SQLITE_PRIVATE void *sqlite3Malloc(u64 n){
  void *p;
  if( n==0 || n>SQLITE_MAX_ALLOCATION_SIZE ){





    p = 0;
  }else if( sqlite3GlobalConfig.bMemstat ){
    sqlite3_mutex_enter(mem0.mutex);
    mallocWithAlarm((int)n, &p);
    sqlite3_mutex_leave(mem0.mutex);
  }else{
    p = sqlite3GlobalConfig.m.xMalloc((int)n);

}

/*
** TRUE if p is a lookaside memory allocation from db
*/
#ifndef SQLITE_OMIT_LOOKASIDE
static int isLookaside(sqlite3 *db, const void *p){
  return SQLITE_WITHIN(p, db->lookaside.pStart, db->lookaside.pTrueEnd);
}
#else
#define isLookaside(A,B) 0
#endif

/*
** Return the size of a memory allocation previously obtained from

#else
  return db->lookaside.szTrue;
#endif
}
SQLITE_PRIVATE int sqlite3DbMallocSize(sqlite3 *db, const void *p){
  assert( p!=0 );
#ifdef SQLITE_DEBUG

  if( db==0 ){
    assert( sqlite3MemdebugNoType(p, (u8)~MEMTYPE_HEAP) );
    assert( sqlite3MemdebugHasType(p, MEMTYPE_HEAP) );
  }else if( !isLookaside(db,p) ){
    assert( sqlite3MemdebugHasType(p, (MEMTYPE_LOOKASIDE|MEMTYPE_HEAP)) );
    assert( sqlite3MemdebugNoType(p, (u8)~(MEMTYPE_LOOKASIDE|MEMTYPE_HEAP)) );

  }
#endif
  if( db ){
    if( ((uptr)p)<(uptr)(db->lookaside.pTrueEnd) ){
#ifndef SQLITE_OMIT_TWOSIZE_LOOKASIDE
      if( ((uptr)p)>=(uptr)(db->lookaside.pMiddle) ){
        assert( sqlite3_mutex_held(db->mutex) );
        return LOOKASIDE_SMALL;
      }
#endif
      if( ((uptr)p)>=(uptr)(db->lookaside.pStart) ){

** connection.  Calling sqlite3DbFree(D,X) for X==0 is a harmless no-op.
** The sqlite3DbFreeNN(D,X) version requires that X be non-NULL.
*/
SQLITE_PRIVATE void sqlite3DbFreeNN(sqlite3 *db, void *p){
  assert( db==0 || sqlite3_mutex_held(db->mutex) );
  assert( p!=0 );
  if( db ){




    if( ((uptr)p)<(uptr)(db->lookaside.pEnd) ){
#ifndef SQLITE_OMIT_TWOSIZE_LOOKASIDE
      if( ((uptr)p)>=(uptr)(db->lookaside.pMiddle) ){
        LookasideSlot *pBuf = (LookasideSlot*)p;
        assert( db->pnBytesFreed==0 );
#ifdef SQLITE_DEBUG
        memset(p, 0xaa, LOOKASIDE_SMALL);  /* Trash freed content */
#endif
        pBuf->pNext = db->lookaside.pSmallFree;
        db->lookaside.pSmallFree = pBuf;
        return;
      }
#endif /* SQLITE_OMIT_TWOSIZE_LOOKASIDE */
      if( ((uptr)p)>=(uptr)(db->lookaside.pStart) ){
        LookasideSlot *pBuf = (LookasideSlot*)p;
        assert( db->pnBytesFreed==0 );
#ifdef SQLITE_DEBUG
        memset(p, 0xaa, db->lookaside.szTrue);  /* Trash freed content */
#endif
        pBuf->pNext = db->lookaside.pFree;
        db->lookaside.pFree = pBuf;
        return;
      }
    }
    if( db->pnBytesFreed ){
      measureAllocationSize(db, p);
      return;
    }
  }
  assert( sqlite3MemdebugHasType(p, (MEMTYPE_LOOKASIDE|MEMTYPE_HEAP)) );
  assert( sqlite3MemdebugNoType(p, (u8)~(MEMTYPE_LOOKASIDE|MEMTYPE_HEAP)) );
  assert( db!=0 || sqlite3MemdebugNoType(p, MEMTYPE_LOOKASIDE) );
  sqlite3MemdebugSetType(p, MEMTYPE_HEAP);
  sqlite3_free(p);
}
SQLITE_PRIVATE void sqlite3DbNNFreeNN(sqlite3 *db, void *p){
  assert( db!=0 );
  assert( sqlite3_mutex_held(db->mutex) );
  assert( p!=0 );
  if( ((uptr)p)<(uptr)(db->lookaside.pEnd) ){
#ifndef SQLITE_OMIT_TWOSIZE_LOOKASIDE
    if( ((uptr)p)>=(uptr)(db->lookaside.pMiddle) ){
      LookasideSlot *pBuf = (LookasideSlot*)p;
      assert( db->pnBytesFreed==0 );
#ifdef SQLITE_DEBUG
      memset(p, 0xaa, LOOKASIDE_SMALL);  /* Trash freed content */
#endif
      pBuf->pNext = db->lookaside.pSmallFree;
      db->lookaside.pSmallFree = pBuf;
      return;
    }
#endif /* SQLITE_OMIT_TWOSIZE_LOOKASIDE */
    if( ((uptr)p)>=(uptr)(db->lookaside.pStart) ){
      LookasideSlot *pBuf = (LookasideSlot*)p;
      assert( db->pnBytesFreed==0 );
#ifdef SQLITE_DEBUG
      memset(p, 0xaa, db->lookaside.szTrue);  /* Trash freed content */
#endif
      pBuf->pNext = db->lookaside.pFree;
      db->lookaside.pFree = pBuf;
      return;
    }
  }
  if( db->pnBytesFreed ){
    measureAllocationSize(db, p);
    return;
  }
  assert( sqlite3MemdebugHasType(p, (MEMTYPE_LOOKASIDE|MEMTYPE_HEAP)) );
  assert( sqlite3MemdebugNoType(p, (u8)~(MEMTYPE_LOOKASIDE|MEMTYPE_HEAP)) );
  sqlite3MemdebugSetType(p, MEMTYPE_HEAP);
  sqlite3_free(p);
}
SQLITE_PRIVATE void sqlite3DbFree(sqlite3 *db, void *p){
  assert( db==0 || sqlite3_mutex_held(db->mutex) );
  if( p ) sqlite3DbFreeNN(db, p);
}

/*
** Change the size of an existing memory allocation

/*
** The text between zStart and zEnd represents a phrase within a larger
** SQL statement.  Make a copy of this phrase in space obtained form
** sqlite3DbMalloc().  Omit leading and trailing whitespace.
*/
SQLITE_PRIVATE char *sqlite3DbSpanDup(sqlite3 *db, const char *zStart, const char *zEnd){
  int n;
#ifdef SQLITE_DEBUG
  /* Because of the way the parser works, the span is guaranteed to contain
  ** at least one non-space character */
  for(n=0; sqlite3Isspace(zStart[n]); n++){ assert( &zStart[n]<zEnd ); }
#endif
  while( sqlite3Isspace(zStart[0]) ) zStart++;
  n = (int)(zEnd - zStart);
  while( sqlite3Isspace(zStart[n-1]) ) n--;
  return sqlite3DbStrNDup(db, zStart, n);
}

/*
** Free any prior content in *pz and replace it with a copy of zNew.
*/
SQLITE_PRIVATE void sqlite3SetString(char **pz, sqlite3 *db, const char *zNew){

  if( db->mallocFailed==0 && db->bBenignMalloc==0 ){
    db->mallocFailed = 1;
    if( db->nVdbeExec>0 ){
      AtomicStore(&db->u1.isInterrupted, 1);
    }
    DisableLookaside;
    if( db->pParse ){
      Parse *pParse;
      sqlite3ErrorMsg(db->pParse, "out of memory");
      db->pParse->rc = SQLITE_NOMEM_BKPT;
      for(pParse=db->pParse->pOuterParse; pParse; pParse = pParse->pOuterParse){
        pParse->nErr++;
        pParse->rc = SQLITE_NOMEM;
      }
    }
  }
  return 0;
}

/*
** This routine reactivates the memory allocator and clears the

            buf[1] = 0x80 + (u8)((ch>>12) & 0x3f);
            buf[2] = 0x80 + (u8)((ch>>6) & 0x3f);
            buf[3] = 0x80 + (u8)(ch & 0x3f);
            length = 4;
          }
        }
        if( precision>1 ){
          i64 nPrior = 1;
          width -= precision-1;
          if( width>1 && !flag_leftjustify ){
            sqlite3_str_appendchar(pAccum, width-1, ' ');
            width = 0;
          }
          sqlite3_str_append(pAccum, buf, length);
          precision--;
          while( precision > 1 ){
            i64 nCopyBytes;
            if( nPrior > precision-1 ) nPrior = precision - 1;
            nCopyBytes = length*nPrior;
            if( nCopyBytes + pAccum->nChar >= pAccum->nAlloc ){
              sqlite3StrAccumEnlarge(pAccum, nCopyBytes);
            }
            if( pAccum->accError ) break;
            sqlite3_str_append(pAccum,
                 &pAccum->zText[pAccum->nChar-nCopyBytes], nCopyBytes);
            precision -= nPrior;
            nPrior *= 2;
          }
        }
        bufpt = buf;
        flag_altform2 = 1;
        goto adjust_width_for_utf8;
      case etSTRING:
      case etDYNSTRING:

          int ii = length - 1;
          while( ii>=0 ) if( (bufpt[ii--] & 0xc0)==0x80 ) width++;
        }
        break;
      case etSQLESCAPE:           /* %q: Escape ' characters */
      case etSQLESCAPE2:          /* %Q: Escape ' and enclose in '...' */
      case etSQLESCAPE3: {        /* %w: Escape " characters */
        i64 i, j, k, n;
        int needQuote, isnull;
        char ch;
        char q = ((xtype==etSQLESCAPE3)?'"':'\'');   /* Quote character */
        char *escarg;

        if( bArgList ){
          escarg = getTextArg(pArgList);
        }else{

/*
** Enlarge the memory allocation on a StrAccum object so that it is
** able to accept at least N more bytes of text.
**
** Return the number of bytes of text that StrAccum is able to accept
** after the attempted enlargement.  The value returned might be zero.
*/
SQLITE_PRIVATE int sqlite3StrAccumEnlarge(StrAccum *p, i64 N){
  char *zNew;
  assert( p->nChar+N >= p->nAlloc ); /* Only called if really needed */
  if( p->accError ){
    testcase(p->accError==SQLITE_TOOBIG);
    testcase(p->accError==SQLITE_NOMEM);
    return 0;
  }
  if( p->mxAlloc==0 ){
    sqlite3StrAccumSetError(p, SQLITE_TOOBIG);
    return p->nAlloc - p->nChar - 1;
  }else{
    char *zOld = isMalloced(p) ? p->zText : 0;
    i64 szNew = p->nChar + N + 1;

    if( szNew+p->nChar<=p->mxAlloc ){
      /* Force exponential buffer size growth as long as it does not overflow,
      ** to avoid having to call this routine too often */
      szNew += p->nChar;
    }
    if( szNew > p->mxAlloc ){
      sqlite3_str_reset(p);

      p->printfFlags |= SQLITE_PRINTF_MALLOCED;
    }else{
      sqlite3_str_reset(p);
      sqlite3StrAccumSetError(p, SQLITE_NOMEM);
      return 0;
    }
  }
  assert( N>=0 && N<=0x7fffffff );
  return (int)N;
}

/*
** Append N copies of character c to the given string buffer.
*/
SQLITE_API void sqlite3_str_appendchar(sqlite3_str *p, int N, char c){
  testcase( p->nChar + (i64)N > 0x7fffffff );

  u8 moreToFollow
){
  int i;
  sqlite3TreeViewPush(&pView, moreToFollow);
  sqlite3TreeViewLine(pView, "COLUMNS");
  for(i=0; i<nCol; i++){
    u16 flg = aCol[i].colFlags;
    int colMoreToFollow = i<(nCol - 1);
    sqlite3TreeViewPush(&pView, colMoreToFollow);
    sqlite3TreeViewLine(pView, 0);
    printf(" %s", aCol[i].zCnName);
    switch( aCol[i].eCType ){
      case COLTYPE_ANY:      printf(" ANY");        break;
      case COLTYPE_BLOB:     printf(" BLOB");       break;
      case COLTYPE_INT:      printf(" INT");        break;
      case COLTYPE_INTEGER:  printf(" INTEGER");    break;

    }
    if( pItem->fg.isCte ){
      sqlite3_str_appendf(&x, " CteUse=0x%p", pItem->u2.pCteUse);
    }
    if( pItem->fg.isOn || (pItem->fg.isUsing==0 && pItem->u3.pOn!=0) ){
      sqlite3_str_appendf(&x, " ON");
    }
    if( pItem->fg.isTabFunc )      sqlite3_str_appendf(&x, " isTabFunc");
    if( pItem->fg.isCorrelated )   sqlite3_str_appendf(&x, " isCorrelated");
    if( pItem->fg.isMaterialized ) sqlite3_str_appendf(&x, " isMaterialized");
    if( pItem->fg.viaCoroutine )   sqlite3_str_appendf(&x, " viaCoroutine");
    if( pItem->fg.notCte )         sqlite3_str_appendf(&x, " notCte");
    if( pItem->fg.isNestedFrom )   sqlite3_str_appendf(&x, " isNestedFrom");

    sqlite3StrAccumFinish(&x);
    sqlite3TreeViewItem(pView, zLine, i<pSrc->nSrc-1);
    n = 0;
    if( pItem->pSelect ) n++;
    if( pItem->fg.isTabFunc ) n++;
    if( pItem->fg.isUsing ) n++;
    if( pItem->fg.isUsing ){
      sqlite3TreeViewIdList(pView, pItem->u3.pUsing, (--n)>0, "USING");
    }
    if( pItem->pSelect ){
      if( pItem->pTab ){
        Table *pTab = pItem->pTab;
        sqlite3TreeViewColumnList(pView, pTab->aCol, pTab->nCol, 1);
      }
      assert( (int)pItem->fg.isNestedFrom == IsNestedFrom(pItem->pSelect) );
      sqlite3TreeViewSelect(pView, pItem->pSelect, (--n)>0);
    }
    if( pItem->fg.isTabFunc ){
      sqlite3TreeViewExprList(pView, pItem->u1.pFuncArg, 0, "func-args:");
    }
    sqlite3TreeViewPop(&pView);
  }

  char zFlgs[200];
  sqlite3TreeViewPush(&pView, moreToFollow);
  if( pExpr==0 ){
    sqlite3TreeViewLine(pView, "nil");
    sqlite3TreeViewPop(&pView);
    return;
  }
  if( pExpr->flags || pExpr->affExpr || pExpr->vvaFlags || pExpr->pAggInfo ){
    StrAccum x;
    sqlite3StrAccumInit(&x, 0, zFlgs, sizeof(zFlgs), 0);
    sqlite3_str_appendf(&x, " fg.af=%x.%c",
      pExpr->flags, pExpr->affExpr ? pExpr->affExpr : 'n');
    if( ExprHasProperty(pExpr, EP_OuterON) ){
      sqlite3_str_appendf(&x, " outer.iJoin=%d", pExpr->w.iJoin);
    }
    if( ExprHasProperty(pExpr, EP_InnerON) ){
      sqlite3_str_appendf(&x, " inner.iJoin=%d", pExpr->w.iJoin);
    }
    if( ExprHasProperty(pExpr, EP_FromDDL) ){
      sqlite3_str_appendf(&x, " DDL");
    }
    if( ExprHasVVAProperty(pExpr, EP_Immutable) ){
      sqlite3_str_appendf(&x, " IMMUTABLE");
    }
    if( pExpr->pAggInfo!=0 ){
      sqlite3_str_appendf(&x, " agg-column[%d]", pExpr->iAgg);
    }
    sqlite3StrAccumFinish(&x);
  }else{
    zFlgs[0] = 0;
  }
  switch( pExpr->op ){
    case TK_AGG_COLUMN: {
      sqlite3TreeViewLine(pView, "AGG{%d:%d}%s",

    }
    sqlite3TreeViewPop(&pView);
    pUpsert = pUpsert->pNextUpsert;
  }
  sqlite3TreeViewPop(&pView);
}

#if TREETRACE_ENABLED
/*
** Generate a human-readable diagram of the data structure that go
** into generating an DELETE statement.
*/
SQLITE_PRIVATE void sqlite3TreeViewDelete(
  const With *pWith,
  const SrcList *pTabList,

    sqlite3TreeViewPop(&pView);
  }
  if( pTrigger ){
    sqlite3TreeViewTrigger(pView, pTrigger, (--n)>0, 1);
  }
  sqlite3TreeViewPop(&pView);
}
#endif /* TREETRACE_ENABLED */

#if TREETRACE_ENABLED
/*
** Generate a human-readable diagram of the data structure that go
** into generating an INSERT statement.
*/
SQLITE_PRIVATE void sqlite3TreeViewInsert(
  const With *pWith,
  const SrcList *pTabList,

    sqlite3TreeViewPop(&pView);
  }
  if( pTrigger ){
    sqlite3TreeViewTrigger(pView, pTrigger, (--n)>0, 1);
  }
  sqlite3TreeViewPop(&pView);
}
#endif /* TREETRACE_ENABLED */

#if TREETRACE_ENABLED
/*
** Generate a human-readable diagram of the data structure that go
** into generating an UPDATE statement.
*/
SQLITE_PRIVATE void sqlite3TreeViewUpdate(
  const With *pWith,
  const SrcList *pTabList,

    sqlite3TreeViewPop(&pView);
  }
  if( pTrigger ){
    sqlite3TreeViewTrigger(pView, pTrigger, (--n)>0, 1);
  }
  sqlite3TreeViewPop(&pView);
}
#endif /* TREETRACE_ENABLED */

#ifndef SQLITE_OMIT_TRIGGER
/*
** Show a human-readable graph of a TriggerStep
*/
SQLITE_PRIVATE void sqlite3TreeViewTriggerStep(
  TreeView *pView,

/* #include "sqliteInt.h" */


/* All threads share a single random number generator.
** This structure is the current state of the generator.
*/
static SQLITE_WSD struct sqlite3PrngType {
  u32 s[16];                 /* 64 bytes of chacha20 state */
  u8 out[64];                /* Output bytes */
  u8 n;                      /* Output bytes remaining */
} sqlite3Prng;


/* The RFC-7539 ChaCha20 block function
*/
#define ROTL(a,b) (((a) << (b)) | ((a) >> (32 - (b))))
#define QR(a, b, c, d) ( \
    a += b, d ^= a, d = ROTL(d,16), \
    c += d, b ^= c, b = ROTL(b,12), \
    a += b, d ^= a, d = ROTL(d, 8), \
    c += d, b ^= c, b = ROTL(b, 7))
static void chacha_block(u32 *out, const u32 *in){
  int i;
  u32 x[16];
  memcpy(x, in, 64);
  for(i=0; i<10; i++){
    QR(x[0], x[4], x[ 8], x[12]);
    QR(x[1], x[5], x[ 9], x[13]);
    QR(x[2], x[6], x[10], x[14]);
    QR(x[3], x[7], x[11], x[15]);
    QR(x[0], x[5], x[10], x[15]);
    QR(x[1], x[6], x[11], x[12]);
    QR(x[2], x[7], x[ 8], x[13]);
    QR(x[3], x[4], x[ 9], x[14]);
  }
  for(i=0; i<16; i++) out[i] = x[i]+in[i];
}

/*
** Return N random bytes.
*/
SQLITE_API void sqlite3_randomness(int N, void *pBuf){

  unsigned char *zBuf = pBuf;

  /* The "wsdPrng" macro will resolve to the pseudo-random number generator
  ** state vector.  If writable static data is unsupported on the target,
  ** we have to locate the state vector at run-time.  In the more common
  ** case where writable static data is supported, wsdPrng can refer directly
  ** to the "sqlite3Prng" state vector declared above.

#if SQLITE_THREADSAFE
  mutex = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_PRNG);
#endif

  sqlite3_mutex_enter(mutex);
  if( N<=0 || pBuf==0 ){
    wsdPrng.s[0] = 0;
    sqlite3_mutex_leave(mutex);
    return;
  }

  /* Initialize the state of the random number generator once,
  ** the first time this routine is called.






  */
  if( wsdPrng.s[0]==0 ){
    sqlite3_vfs *pVfs = sqlite3_vfs_find(0);

    static const u32 chacha20_init[] = {
      0x61707865, 0x3320646e, 0x79622d32, 0x6b206574
    };
    memcpy(&wsdPrng.s[0], chacha20_init, 16);

    if( NEVER(pVfs==0) ){
      memset(&wsdPrng.s[4], 0, 44);
    }else{
      sqlite3OsRandomness(pVfs, 44, (char*)&wsdPrng.s[4]);
    }





    wsdPrng.s[15] = wsdPrng.s[12];

    wsdPrng.s[12] = 0;

    wsdPrng.n = 0;
  }

  assert( N>0 );
  while( 1 /* exit by break */ ){
    if( N<=wsdPrng.n ){
      memcpy(zBuf, &wsdPrng.out[wsdPrng.n-N], N);

      wsdPrng.n -= N;
      break;
    }
    if( wsdPrng.n>0 ){
      memcpy(zBuf, wsdPrng.out, wsdPrng.n);
      N -= wsdPrng.n;
      zBuf += wsdPrng.n;
    }
    wsdPrng.s[12]++;
    chacha_block((u32*)wsdPrng.out, wsdPrng.s);
    wsdPrng.n = 64;
  }
  sqlite3_mutex_leave(mutex);
}

#ifndef SQLITE_UNTESTABLE
/*
** For testing purposes, we sometimes want to preserve the state of
** PRNG and restore the PRNG to its saved state at a later time, or

    va_start(ap, zFormat);
    z = sqlite3VMPrintf(db, zFormat, ap);
    va_end(ap);
    sqlite3ValueSetStr(db->pErr, -1, z, SQLITE_UTF8, SQLITE_DYNAMIC);
  }
}

/*
** Check for interrupts and invoke progress callback.
*/
SQLITE_PRIVATE void sqlite3ProgressCheck(Parse *p){
  sqlite3 *db = p->db;
  if( AtomicLoad(&db->u1.isInterrupted) ){
    p->nErr++;
    p->rc = SQLITE_INTERRUPT;
  }
#ifndef SQLITE_OMIT_PROGRESS_CALLBACK
  if( db->xProgress && (++p->nProgressSteps)>=db->nProgressOps ){
    if( db->xProgress(db->pProgressArg) ){
      p->nErr++;
      p->rc = SQLITE_INTERRUPT;
    }
    p->nProgressSteps = 0;
  }
#endif
}

/*
** Add an error message to pParse->zErrMsg and increment pParse->nErr.
**
** This function should be used to report any error that occurs while
** compiling an SQL statement (i.e. within sqlite3_prepare()). The
** last thing the sqlite3_prepare() function does is copy the error
** stored by this function into the database handle using sqlite3Error().
** Functions sqlite3Error() or sqlite3ErrorWithMsg() should be used
** during statement execution (sqlite3_step() etc.).
*/
SQLITE_PRIVATE void sqlite3ErrorMsg(Parse *pParse, const char *zFormat, ...){
  char *zMsg;
  va_list ap;
  sqlite3 *db = pParse->db;
  assert( db!=0 );
  assert( db->pParse==pParse || db->pParse->pToplevel==pParse );
  db->errByteOffset = -2;
  va_start(ap, zFormat);
  zMsg = sqlite3VMPrintf(db, zFormat, ap);
  va_end(ap);
  if( db->errByteOffset<-1 ) db->errByteOffset = -1;
  if( db->suppressErr ){
    sqlite3DbFree(db, zMsg);

#endif /* SQLITE_OMIT_FLOATING_POINT */
}
#if defined(_MSC_VER)
#pragma warning(default : 4756)
#endif

/*
** Render an signed 64-bit integer as text.  Store the result in zOut[] and
** return the length of the string that was stored, in bytes.  The value
** returned does not include the zero terminator at the end of the output
** string.
**
** The caller must ensure that zOut[] is at least 21 bytes in size.
*/
SQLITE_PRIVATE int sqlite3Int64ToText(i64 v, char *zOut){
  int i;
  u64 x;
  char zTemp[22];
  if( v<0 ){
    x = (v==SMALLEST_INT64) ? ((u64)1)<<63 : (u64)-v;
  }else{
    x = v;
  }
  i = sizeof(zTemp)-2;
  zTemp[sizeof(zTemp)-1] = 0;
  do{
    zTemp[i--] = (x%10) + '0';
    x = x/10;
  }while( x );
  if( v<0 ) zTemp[i--] = '-';
  memcpy(zOut, &zTemp[i+1], sizeof(zTemp)-1-i);
  return sizeof(zTemp)-2-i;
}

/*
** Compare the 19-character string zNum against the text representation
** value 2^63:  9223372036854775808.  Return negative, zero, or positive
** if zNum is less than, equal to, or greater than the string.
** Note that zNum must contain exactly 19 characters.

    const char *z = (const char*)&pIn[i+2];
    if( strncmp(z,zName,nName)==0 && z[nName]==0 ) return pIn[i];
    i += pIn[i+1];
  }while( i<mx );
  return 0;
}

/*
** High-resolution hardware timer used for debugging and testing only.
*/
#if defined(VDBE_PROFILE)  \
 || defined(SQLITE_PERFORMANCE_TRACE) \
 || defined(SQLITE_ENABLE_STMT_SCANSTATUS)
/************** Include hwtime.h in the middle of util.c *********************/
/************** Begin file hwtime.h ******************************************/
/*
** 2008 May 27
**
** The author disclaims copyright to this source code.  In place of
** a legal notice, here is a blessing:
**
**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
******************************************************************************
**
** This file contains inline asm code for retrieving "high-performance"
** counters for x86 and x86_64 class CPUs.
*/
#ifndef SQLITE_HWTIME_H
#define SQLITE_HWTIME_H

/*
** The following routine only works on pentium-class (or newer) processors.
** It uses the RDTSC opcode to read the cycle count value out of the
** processor and returns that value.  This can be used for high-res
** profiling.
*/
#if !defined(__STRICT_ANSI__) && \
    (defined(__GNUC__) || defined(_MSC_VER)) && \
    (defined(i386) || defined(__i386__) || defined(_M_IX86))

  #if defined(__GNUC__)

  __inline__ sqlite_uint64 sqlite3Hwtime(void){
     unsigned int lo, hi;
     __asm__ __volatile__ ("rdtsc" : "=a" (lo), "=d" (hi));
     return (sqlite_uint64)hi << 32 | lo;
  }

  #elif defined(_MSC_VER)

  __declspec(naked) __inline sqlite_uint64 __cdecl sqlite3Hwtime(void){
     __asm {
        rdtsc
        ret       ; return value at EDX:EAX
     }
  }

  #endif

#elif !defined(__STRICT_ANSI__) && (defined(__GNUC__) && defined(__x86_64__))

  __inline__ sqlite_uint64 sqlite3Hwtime(void){
     unsigned int lo, hi;
     __asm__ __volatile__ ("rdtsc" : "=a" (lo), "=d" (hi));
     return (sqlite_uint64)hi << 32 | lo;
  }

#elif !defined(__STRICT_ANSI__) && (defined(__GNUC__) && defined(__ppc__))

  __inline__ sqlite_uint64 sqlite3Hwtime(void){
      unsigned long long retval;
      unsigned long junk;
      __asm__ __volatile__ ("\n\
          1:      mftbu   %1\n\
                  mftb    %L0\n\
                  mftbu   %0\n\
                  cmpw    %0,%1\n\
                  bne     1b"
                  : "=r" (retval), "=r" (junk));
      return retval;
  }

#else

  /*
  ** asm() is needed for hardware timing support.  Without asm(),
  ** disable the sqlite3Hwtime() routine.
  **
  ** sqlite3Hwtime() is only used for some obscure debugging
  ** and analysis configurations, not in any deliverable, so this
  ** should not be a great loss.
  */
SQLITE_PRIVATE   sqlite_uint64 sqlite3Hwtime(void){ return ((sqlite_uint64)0); }

#endif

#endif /* !defined(SQLITE_HWTIME_H) */

/************** End of hwtime.h **********************************************/
/************** Continuing where we left off in util.c ***********************/
#endif

/************** End of util.c ************************************************/
/************** Begin file hash.c ********************************************/
/*
** 2001 September 22
**
** The author disclaims copyright to this source code.  In place of
** a legal notice, here is a blessing:

    count = pEntry->count;
  }else{
    h = 0;
    elem = pH->first;
    count = pH->count;
  }
  if( pHash ) *pHash = h;
  while( count ){
    assert( elem!=0 );
    if( sqlite3StrICmp(elem->pKey,pKey)==0 ){
      return elem;
    }
    elem = elem->next;
    count--;
  }
  return &nullElement;
}

/* Remove a single entry from the hash table given a pointer to that
** element and a hash on the element's key.
*/

    /*   1 */ "AutoCommit"       OpHelp(""),
    /*   2 */ "Transaction"      OpHelp(""),
    /*   3 */ "Checkpoint"       OpHelp(""),
    /*   4 */ "JournalMode"      OpHelp(""),
    /*   5 */ "Vacuum"           OpHelp(""),
    /*   6 */ "VFilter"          OpHelp("iplan=r[P3] zplan='P4'"),
    /*   7 */ "VUpdate"          OpHelp("data=r[P3@P2]"),
    /*   8 */ "Init"             OpHelp("Start at P2"),
    /*   9 */ "Goto"             OpHelp(""),
    /*  10 */ "Gosub"            OpHelp(""),
    /*  11 */ "InitCoroutine"    OpHelp(""),
    /*  12 */ "Yield"            OpHelp(""),
    /*  13 */ "MustBeInt"        OpHelp(""),
    /*  14 */ "Jump"             OpHelp(""),
    /*  15 */ "Once"             OpHelp(""),
    /*  16 */ "If"               OpHelp(""),
    /*  17 */ "IfNot"            OpHelp(""),
    /*  18 */ "IsType"           OpHelp("if typeof(P1.P3) in P5 goto P2"),

    /*  19 */ "Not"              OpHelp("r[P2]= !r[P1]"),
    /*  20 */ "IfNullRow"        OpHelp("if P1.nullRow then r[P3]=NULL, goto P2"),
    /*  21 */ "SeekLT"           OpHelp("key=r[P3@P4]"),
    /*  22 */ "SeekLE"           OpHelp("key=r[P3@P4]"),
    /*  23 */ "SeekGE"           OpHelp("key=r[P3@P4]"),
    /*  24 */ "SeekGT"           OpHelp("key=r[P3@P4]"),
    /*  25 */ "IfNotOpen"        OpHelp("if( !csr[P1] ) goto P2"),
    /*  26 */ "IfNoHope"         OpHelp("key=r[P3@P4]"),
    /*  27 */ "NoConflict"       OpHelp("key=r[P3@P4]"),
    /*  28 */ "NotFound"         OpHelp("key=r[P3@P4]"),
    /*  29 */ "Found"            OpHelp("key=r[P3@P4]"),
    /*  30 */ "SeekRowid"        OpHelp("intkey=r[P3]"),
    /*  31 */ "NotExists"        OpHelp("intkey=r[P3]"),
    /*  32 */ "Last"             OpHelp(""),
    /*  33 */ "IfSmaller"        OpHelp(""),
    /*  34 */ "SorterSort"       OpHelp(""),
    /*  35 */ "Sort"             OpHelp(""),
    /*  36 */ "Rewind"           OpHelp(""),
    /*  37 */ "SorterNext"       OpHelp(""),
    /*  38 */ "Prev"             OpHelp(""),
    /*  39 */ "Next"             OpHelp(""),
    /*  40 */ "IdxLE"            OpHelp("key=r[P3@P4]"),
    /*  41 */ "IdxGT"            OpHelp("key=r[P3@P4]"),
    /*  42 */ "IdxLT"            OpHelp("key=r[P3@P4]"),

    /*  43 */ "Or"               OpHelp("r[P3]=(r[P1] || r[P2])"),
    /*  44 */ "And"              OpHelp("r[P3]=(r[P1] && r[P2])"),
    /*  45 */ "IdxGE"            OpHelp("key=r[P3@P4]"),
    /*  46 */ "RowSetRead"       OpHelp("r[P3]=rowset(P1)"),
    /*  47 */ "RowSetTest"       OpHelp("if r[P3] in rowset(P1) goto P2"),
    /*  48 */ "Program"          OpHelp(""),
    /*  49 */ "FkIfZero"         OpHelp("if fkctr[P1]==0 goto P2"),

    /*  50 */ "IsNull"           OpHelp("if r[P1]==NULL goto P2"),
    /*  51 */ "NotNull"          OpHelp("if r[P1]!=NULL goto P2"),
    /*  52 */ "Ne"               OpHelp("IF r[P3]!=r[P1]"),
    /*  53 */ "Eq"               OpHelp("IF r[P3]==r[P1]"),
    /*  54 */ "Gt"               OpHelp("IF r[P3]>r[P1]"),
    /*  55 */ "Le"               OpHelp("IF r[P3]<=r[P1]"),
    /*  56 */ "Lt"               OpHelp("IF r[P3]<r[P1]"),
    /*  57 */ "Ge"               OpHelp("IF r[P3]>=r[P1]"),
    /*  58 */ "ElseEq"           OpHelp(""),
    /*  59 */ "IfPos"            OpHelp("if r[P1]>0 then r[P1]-=P3, goto P2"),
    /*  60 */ "IfNotZero"        OpHelp("if r[P1]!=0 then r[P1]--, goto P2"),
    /*  61 */ "DecrJumpZero"     OpHelp("if (--r[P1])==0 goto P2"),
    /*  62 */ "IncrVacuum"       OpHelp(""),
    /*  63 */ "VNext"            OpHelp(""),
    /*  64 */ "Filter"           OpHelp("if key(P3@P4) not in filter(P1) goto P2"),

    /*  65 */ "PureFunc"         OpHelp("r[P3]=func(r[P2@NP])"),
    /*  66 */ "Function"         OpHelp("r[P3]=func(r[P2@NP])"),
    /*  67 */ "Return"           OpHelp(""),
    /*  68 */ "EndCoroutine"     OpHelp(""),
    /*  69 */ "HaltIfNull"       OpHelp("if r[P3]=null halt"),
    /*  70 */ "Halt"             OpHelp(""),
    /*  71 */ "Integer"          OpHelp("r[P2]=P1"),

    /* 186 */ "Abortable"        OpHelp(""),
  };
  return azName[i];
}
#endif

/************** End of opcodes.c *********************************************/
/************** Begin file os_kv.c *******************************************/
/*
** 2022-09-06
**
** The author disclaims copyright to this source code.  In place of
** a legal notice, here is a blessing:
**
**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
******************************************************************************
**
** This file contains an experimental VFS layer that operates on a
** Key/Value storage engine where both keys and values must be pure
** text.
*/
/* #include <sqliteInt.h> */
#if SQLITE_OS_KV || (SQLITE_OS_UNIX && defined(SQLITE_OS_KV_OPTIONAL))

/*****************************************************************************
** Debugging logic
*/

/* SQLITE_KV_TRACE() is used for tracing calls to kvstorage routines. */
#if 0
#define SQLITE_KV_TRACE(X)  printf X
#else
#define SQLITE_KV_TRACE(X)
#endif

/* SQLITE_KV_LOG() is used for tracing calls to the VFS interface */
#if 0
#define SQLITE_KV_LOG(X)  printf X
#else
#define SQLITE_KV_LOG(X)
#endif


/*
** Forward declaration of objects used by this VFS implementation
*/
typedef struct KVVfsFile KVVfsFile;

/* A single open file.  There are only two files represented by this
** VFS - the database and the rollback journal.
*/
struct KVVfsFile {
  sqlite3_file base;              /* IO methods */
  const char *zClass;             /* Storage class */
  int isJournal;                  /* True if this is a journal file */
  unsigned int nJrnl;             /* Space allocated for aJrnl[] */
  char *aJrnl;                    /* Journal content */
  int szPage;                     /* Last known page size */
  sqlite3_int64 szDb;             /* Database file size.  -1 means unknown */
  char *aData;                    /* Buffer to hold page data */
};
#define SQLITE_KVOS_SZ 133073

/*
** Methods for KVVfsFile
*/
static int kvvfsClose(sqlite3_file*);
static int kvvfsReadDb(sqlite3_file*, void*, int iAmt, sqlite3_int64 iOfst);
static int kvvfsReadJrnl(sqlite3_file*, void*, int iAmt, sqlite3_int64 iOfst);
static int kvvfsWriteDb(sqlite3_file*,const void*,int iAmt, sqlite3_int64);
static int kvvfsWriteJrnl(sqlite3_file*,const void*,int iAmt, sqlite3_int64);
static int kvvfsTruncateDb(sqlite3_file*, sqlite3_int64 size);
static int kvvfsTruncateJrnl(sqlite3_file*, sqlite3_int64 size);
static int kvvfsSyncDb(sqlite3_file*, int flags);
static int kvvfsSyncJrnl(sqlite3_file*, int flags);
static int kvvfsFileSizeDb(sqlite3_file*, sqlite3_int64 *pSize);
static int kvvfsFileSizeJrnl(sqlite3_file*, sqlite3_int64 *pSize);
static int kvvfsLock(sqlite3_file*, int);
static int kvvfsUnlock(sqlite3_file*, int);
static int kvvfsCheckReservedLock(sqlite3_file*, int *pResOut);
static int kvvfsFileControlDb(sqlite3_file*, int op, void *pArg);
static int kvvfsFileControlJrnl(sqlite3_file*, int op, void *pArg);
static int kvvfsSectorSize(sqlite3_file*);
static int kvvfsDeviceCharacteristics(sqlite3_file*);

/*
** Methods for sqlite3_vfs
*/
static int kvvfsOpen(sqlite3_vfs*, const char *, sqlite3_file*, int , int *);
static int kvvfsDelete(sqlite3_vfs*, const char *zName, int syncDir);
static int kvvfsAccess(sqlite3_vfs*, const char *zName, int flags, int *);
static int kvvfsFullPathname(sqlite3_vfs*, const char *zName, int, char *zOut);
static void *kvvfsDlOpen(sqlite3_vfs*, const char *zFilename);
static int kvvfsRandomness(sqlite3_vfs*, int nByte, char *zOut);
static int kvvfsSleep(sqlite3_vfs*, int microseconds);
static int kvvfsCurrentTime(sqlite3_vfs*, double*);
static int kvvfsCurrentTimeInt64(sqlite3_vfs*, sqlite3_int64*);

static sqlite3_vfs sqlite3OsKvvfsObject = {
  1,                              /* iVersion */
  sizeof(KVVfsFile),              /* szOsFile */
  1024,                           /* mxPathname */
  0,                              /* pNext */
  "kvvfs",                        /* zName */
  0,                              /* pAppData */
  kvvfsOpen,                      /* xOpen */
  kvvfsDelete,                    /* xDelete */
  kvvfsAccess,                    /* xAccess */
  kvvfsFullPathname,              /* xFullPathname */
  kvvfsDlOpen,                    /* xDlOpen */
  0,                              /* xDlError */
  0,                              /* xDlSym */
  0,                              /* xDlClose */
  kvvfsRandomness,                /* xRandomness */
  kvvfsSleep,                     /* xSleep */
  kvvfsCurrentTime,               /* xCurrentTime */
  0,                              /* xGetLastError */
  kvvfsCurrentTimeInt64           /* xCurrentTimeInt64 */
};

/* Methods for sqlite3_file objects referencing a database file
*/
static sqlite3_io_methods kvvfs_db_io_methods = {
  1,                              /* iVersion */
  kvvfsClose,                     /* xClose */
  kvvfsReadDb,                    /* xRead */
  kvvfsWriteDb,                   /* xWrite */
  kvvfsTruncateDb,                /* xTruncate */
  kvvfsSyncDb,                    /* xSync */
  kvvfsFileSizeDb,                /* xFileSize */
  kvvfsLock,                      /* xLock */
  kvvfsUnlock,                    /* xUnlock */
  kvvfsCheckReservedLock,         /* xCheckReservedLock */
  kvvfsFileControlDb,             /* xFileControl */
  kvvfsSectorSize,                /* xSectorSize */
  kvvfsDeviceCharacteristics,     /* xDeviceCharacteristics */
  0,                              /* xShmMap */
  0,                              /* xShmLock */
  0,                              /* xShmBarrier */
  0,                              /* xShmUnmap */
  0,                              /* xFetch */
  0                               /* xUnfetch */
};

/* Methods for sqlite3_file objects referencing a rollback journal
*/
static sqlite3_io_methods kvvfs_jrnl_io_methods = {
  1,                              /* iVersion */
  kvvfsClose,                     /* xClose */
  kvvfsReadJrnl,                  /* xRead */
  kvvfsWriteJrnl,                 /* xWrite */
  kvvfsTruncateJrnl,              /* xTruncate */
  kvvfsSyncJrnl,                  /* xSync */
  kvvfsFileSizeJrnl,              /* xFileSize */
  kvvfsLock,                      /* xLock */
  kvvfsUnlock,                    /* xUnlock */
  kvvfsCheckReservedLock,         /* xCheckReservedLock */
  kvvfsFileControlJrnl,           /* xFileControl */
  kvvfsSectorSize,                /* xSectorSize */
  kvvfsDeviceCharacteristics,     /* xDeviceCharacteristics */
  0,                              /* xShmMap */
  0,                              /* xShmLock */
  0,                              /* xShmBarrier */
  0,                              /* xShmUnmap */
  0,                              /* xFetch */
  0                               /* xUnfetch */
};

/****** Storage subsystem **************************************************/
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>

/* Forward declarations for the low-level storage engine
*/
static int kvstorageWrite(const char*, const char *zKey, const char *zData);
static int kvstorageDelete(const char*, const char *zKey);
static int kvstorageRead(const char*, const char *zKey, char *zBuf, int nBuf);
#define KVSTORAGE_KEY_SZ  32

/* Expand the key name with an appropriate prefix and put the result
** zKeyOut[].  The zKeyOut[] buffer is assumed to hold at least
** KVSTORAGE_KEY_SZ bytes.
*/
static void kvstorageMakeKey(
  const char *zClass,
  const char *zKeyIn,
  char *zKeyOut
){
  sqlite3_snprintf(KVSTORAGE_KEY_SZ, zKeyOut, "kvvfs-%s-%s", zClass, zKeyIn);
}

/* Write content into a key.  zClass is the particular namespace of the
** underlying key/value store to use - either "local" or "session".
**
** Both zKey and zData are zero-terminated pure text strings.
**
** Return the number of errors.
*/
static int kvstorageWrite(
  const char *zClass,
  const char *zKey,
  const char *zData
){
  FILE *fd;
  char zXKey[KVSTORAGE_KEY_SZ];
  kvstorageMakeKey(zClass, zKey, zXKey);
  fd = fopen(zXKey, "wb");
  if( fd ){
    SQLITE_KV_TRACE(("KVVFS-WRITE  %-15s (%d) %.50s%s\n", zXKey,
                 (int)strlen(zData), zData,
                 strlen(zData)>50 ? "..." : ""));
    fputs(zData, fd);
    fclose(fd);
    return 0;
  }else{
    return 1;
  }
}

/* Delete a key (with its corresponding data) from the key/value
** namespace given by zClass.  If the key does not previously exist,
** this routine is a no-op.
*/
static int kvstorageDelete(const char *zClass, const char *zKey){
  char zXKey[KVSTORAGE_KEY_SZ];
  kvstorageMakeKey(zClass, zKey, zXKey);
  unlink(zXKey);
  SQLITE_KV_TRACE(("KVVFS-DELETE %-15s\n", zXKey));
  return 0;
}

/* Read the value associated with a zKey from the key/value namespace given
** by zClass and put the text data associated with that key in the first
** nBuf bytes of zBuf[].  The value might be truncated if zBuf is not large
** enough to hold it all.  The value put into zBuf must always be zero
** terminated, even if it gets truncated because nBuf is not large enough.
**
** Return the total number of bytes in the data, without truncation, and
** not counting the final zero terminator.   Return -1 if the key does
** not exist.
**
** If nBuf<=0 then this routine simply returns the size of the data without
** actually reading it.
*/
static int kvstorageRead(
  const char *zClass,
  const char *zKey,
  char *zBuf,
  int nBuf
){
  FILE *fd;
  struct stat buf;
  char zXKey[KVSTORAGE_KEY_SZ];
  kvstorageMakeKey(zClass, zKey, zXKey);
  if( access(zXKey, R_OK)!=0
   || stat(zXKey, &buf)!=0
   || !S_ISREG(buf.st_mode)
  ){
    SQLITE_KV_TRACE(("KVVFS-READ   %-15s (-1)\n", zXKey));
    return -1;
  }
  if( nBuf<=0 ){
    return (int)buf.st_size;
  }else if( nBuf==1 ){
    zBuf[0] = 0;
    SQLITE_KV_TRACE(("KVVFS-READ   %-15s (%d)\n", zXKey,
                 (int)buf.st_size));
    return (int)buf.st_size;
  }
  if( nBuf > buf.st_size + 1 ){
    nBuf = buf.st_size + 1;
  }
  fd = fopen(zXKey, "rb");
  if( fd==0 ){
    SQLITE_KV_TRACE(("KVVFS-READ   %-15s (-1)\n", zXKey));
    return -1;
  }else{
    sqlite3_int64 n = fread(zBuf, 1, nBuf-1, fd);
    fclose(fd);
    zBuf[n] = 0;
    SQLITE_KV_TRACE(("KVVFS-READ   %-15s (%lld) %.50s%s\n", zXKey,
                 n, zBuf, n>50 ? "..." : ""));
    return (int)n;
  }
}

/*
** An internal level of indirection which enables us to replace the
** kvvfs i/o methods with JavaScript implementations in WASM builds.
** Maintenance reminder: if this struct changes in any way, the JSON
** rendering of its structure must be updated in
** sqlite3_wasm_enum_json(). There are no binary compatibility
** concerns, so it does not need an iVersion member. This file is
** necessarily always compiled together with sqlite3_wasm_enum_json(),
** and JS code dynamically creates the mapping of members based on
** that JSON description.
*/
typedef struct sqlite3_kvvfs_methods sqlite3_kvvfs_methods;
struct sqlite3_kvvfs_methods {
  int (*xRead)(const char *zClass, const char *zKey, char *zBuf, int nBuf);
  int (*xWrite)(const char *zClass, const char *zKey, const char *zData);
  int (*xDelete)(const char *zClass, const char *zKey);
  const int nKeySize;
};

/*
** This object holds the kvvfs I/O methods which may be swapped out
** for JavaScript-side implementations in WASM builds. In such builds
** it cannot be const, but in native builds it should be so that
** the compiler can hopefully optimize this level of indirection out.
** That said, kvvfs is intended primarily for use in WASM builds.
**
** Note that this is not explicitly flagged as static because the
** amalgamation build will tag it with SQLITE_PRIVATE.
*/
#ifndef SQLITE_WASM
const
#endif
SQLITE_PRIVATE sqlite3_kvvfs_methods sqlite3KvvfsMethods = {
kvstorageRead,
kvstorageWrite,
kvstorageDelete,
KVSTORAGE_KEY_SZ
};

/****** Utility subroutines ************************************************/

/*
** Encode binary into the text encoded used to persist on disk.
** The output text is stored in aOut[], which must be at least
** nData+1 bytes in length.
**
** Return the actual length of the encoded text, not counting the
** zero terminator at the end.
**
** Encoding format
** ---------------
**
**   *  Non-zero bytes are encoded as upper-case hexadecimal
**
**   *  A sequence of one or more zero-bytes that are not at the
**      beginning of the buffer are encoded as a little-endian
**      base-26 number using a..z.  "a" means 0.  "b" means 1,
**      "z" means 25.  "ab" means 26.  "ac" means 52.  And so forth.
**
**   *  Because there is no overlap between the encoding characters
**      of hexadecimal and base-26 numbers, it is always clear where
**      one stops and the next begins.
*/
static int kvvfsEncode(const char *aData, int nData, char *aOut){
  int i, j;
  const unsigned char *a = (const unsigned char*)aData;
  for(i=j=0; i<nData; i++){
    unsigned char c = a[i];
    if( c!=0 ){
      aOut[j++] = "0123456789ABCDEF"[c>>4];
      aOut[j++] = "0123456789ABCDEF"[c&0xf];
    }else{
      /* A sequence of 1 or more zeros is stored as a little-endian
      ** base-26 number using a..z as the digits. So one zero is "b".
      ** Two zeros is "c". 25 zeros is "z", 26 zeros is "ab", 27 is "bb",
      ** and so forth.
      */
      int k;
      for(k=1; i+k<nData && a[i+k]==0; k++){}
      i += k-1;
      while( k>0 ){
        aOut[j++] = 'a'+(k%26);
        k /= 26;
      }
    }
  }
  aOut[j] = 0;
  return j;
}

static const signed char kvvfsHexValue[256] = {
  -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,
   0,  1,  2,  3,  4,  5,  6,  7,    8,  9, -1, -1, -1, -1, -1, -1,
  -1, 10, 11, 12, 13, 14, 15, -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, -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
};

/*
** Decode the text encoding back to binary.  The binary content is
** written into pOut, which must be at least nOut bytes in length.
**
** The return value is the number of bytes actually written into aOut[].
*/
static int kvvfsDecode(const char *a, char *aOut, int nOut){
  int i, j;
  int c;
  const unsigned char *aIn = (const unsigned char*)a;
  i = 0;
  j = 0;
  while( 1 ){
    c = kvvfsHexValue[aIn[i]];
    if( c<0 ){
      int n = 0;
      int mult = 1;
      c = aIn[i];
      if( c==0 ) break;
      while( c>='a' && c<='z' ){
        n += (c - 'a')*mult;
        mult *= 26;
        c = aIn[++i];
      }
      if( j+n>nOut ) return -1;
      memset(&aOut[j], 0, n);
      j += n;
      if( c==0 || mult==1 ) break; /* progress stalled if mult==1 */
    }else{
      aOut[j] = c<<4;
      c = kvvfsHexValue[aIn[++i]];
      if( c<0 ) break;
      aOut[j++] += c;
      i++;
    }
  }
  return j;
}

/*
** Decode a complete journal file.  Allocate space in pFile->aJrnl
** and store the decoding there.  Or leave pFile->aJrnl set to NULL
** if an error is encountered.
**
** The first few characters of the text encoding will be a little-endian
** base-26 number (digits a..z) that is the total number of bytes
** in the decoded journal file image.  This base-26 number is followed
** by a single space, then the encoding of the journal.  The space
** separator is required to act as a terminator for the base-26 number.
*/
static void kvvfsDecodeJournal(
  KVVfsFile *pFile,      /* Store decoding in pFile->aJrnl */
  const char *zTxt,      /* Text encoding.  Zero-terminated */
  int nTxt               /* Bytes in zTxt, excluding zero terminator */
){
  unsigned int n = 0;
  int c, i, mult;
  i = 0;
  mult = 1;
  while( (c = zTxt[i++])>='a' && c<='z' ){
    n += (zTxt[i] - 'a')*mult;
    mult *= 26;
  }
  sqlite3_free(pFile->aJrnl);
  pFile->aJrnl = sqlite3_malloc64( n );
  if( pFile->aJrnl==0 ){
    pFile->nJrnl = 0;
    return;
  }
  pFile->nJrnl = n;
  n = kvvfsDecode(zTxt+i, pFile->aJrnl, pFile->nJrnl);
  if( n<pFile->nJrnl ){
    sqlite3_free(pFile->aJrnl);
    pFile->aJrnl = 0;
    pFile->nJrnl = 0;
  }
}

/*
** Read or write the "sz" element, containing the database file size.
*/
static sqlite3_int64 kvvfsReadFileSize(KVVfsFile *pFile){
  char zData[50];
  zData[0] = 0;
  sqlite3KvvfsMethods.xRead(pFile->zClass, "sz", zData, sizeof(zData)-1);
  return strtoll(zData, 0, 0);
}
static int kvvfsWriteFileSize(KVVfsFile *pFile, sqlite3_int64 sz){
  char zData[50];
  sqlite3_snprintf(sizeof(zData), zData, "%lld", sz);
  return sqlite3KvvfsMethods.xWrite(pFile->zClass, "sz", zData);
}

/****** sqlite3_io_methods methods ******************************************/

/*
** Close an kvvfs-file.
*/
static int kvvfsClose(sqlite3_file *pProtoFile){
  KVVfsFile *pFile = (KVVfsFile *)pProtoFile;

  SQLITE_KV_LOG(("xClose %s %s\n", pFile->zClass,
             pFile->isJournal ? "journal" : "db"));
  sqlite3_free(pFile->aJrnl);
  sqlite3_free(pFile->aData);
  return SQLITE_OK;
}

/*
** Read from the -journal file.
*/
static int kvvfsReadJrnl(
  sqlite3_file *pProtoFile,
  void *zBuf,
  int iAmt,
  sqlite_int64 iOfst
){
  KVVfsFile *pFile = (KVVfsFile*)pProtoFile;
  assert( pFile->isJournal );
  SQLITE_KV_LOG(("xRead('%s-journal',%d,%lld)\n", pFile->zClass, iAmt, iOfst));
  if( pFile->aJrnl==0 ){
    int szTxt = kvstorageRead(pFile->zClass, "jrnl", 0, 0);
    char *aTxt;
    if( szTxt<=4 ){
      return SQLITE_IOERR;
    }
    aTxt = sqlite3_malloc64( szTxt+1 );
    if( aTxt==0 ) return SQLITE_NOMEM;
    kvstorageRead(pFile->zClass, "jrnl", aTxt, szTxt+1);
    kvvfsDecodeJournal(pFile, aTxt, szTxt);
    sqlite3_free(aTxt);
    if( pFile->aJrnl==0 ) return SQLITE_IOERR;
  }
  if( iOfst+iAmt>pFile->nJrnl ){
    return SQLITE_IOERR_SHORT_READ;
  }
  memcpy(zBuf, pFile->aJrnl+iOfst, iAmt);
  return SQLITE_OK;
}

/*
** Read from the database file.
*/
static int kvvfsReadDb(
  sqlite3_file *pProtoFile,
  void *zBuf,
  int iAmt,
  sqlite_int64 iOfst
){
  KVVfsFile *pFile = (KVVfsFile*)pProtoFile;
  unsigned int pgno;
  int got, n;
  char zKey[30];
  char *aData = pFile->aData;
  assert( iOfst>=0 );
  assert( iAmt>=0 );
  SQLITE_KV_LOG(("xRead('%s-db',%d,%lld)\n", pFile->zClass, iAmt, iOfst));
  if( iOfst+iAmt>=512 ){
    if( (iOfst % iAmt)!=0 ){
      return SQLITE_IOERR_READ;
    }
    if( (iAmt & (iAmt-1))!=0 || iAmt<512 || iAmt>65536 ){
      return SQLITE_IOERR_READ;
    }
    pFile->szPage = iAmt;
    pgno = 1 + iOfst/iAmt;
  }else{
    pgno = 1;
  }
  sqlite3_snprintf(sizeof(zKey), zKey, "%u", pgno);
  got = sqlite3KvvfsMethods.xRead(pFile->zClass, zKey,
                                  aData, SQLITE_KVOS_SZ-1);
  if( got<0 ){
    n = 0;
  }else{
    aData[got] = 0;
    if( iOfst+iAmt<512 ){
      int k = iOfst+iAmt;
      aData[k*2] = 0;
      n = kvvfsDecode(aData, &aData[2000], SQLITE_KVOS_SZ-2000);
      if( n>=iOfst+iAmt ){
        memcpy(zBuf, &aData[2000+iOfst], iAmt);
        n = iAmt;
      }else{
        n = 0;
      }
    }else{
      n = kvvfsDecode(aData, zBuf, iAmt);
    }
  }
  if( n<iAmt ){
    memset(zBuf+n, 0, iAmt-n);
    return SQLITE_IOERR_SHORT_READ;
  }
  return SQLITE_OK;
}


/*
** Write into the -journal file.
*/
static int kvvfsWriteJrnl(
  sqlite3_file *pProtoFile,
  const void *zBuf,
  int iAmt,
  sqlite_int64 iOfst
){
  KVVfsFile *pFile = (KVVfsFile*)pProtoFile;
  sqlite3_int64 iEnd = iOfst+iAmt;
  SQLITE_KV_LOG(("xWrite('%s-journal',%d,%lld)\n", pFile->zClass, iAmt, iOfst));
  if( iEnd>=0x10000000 ) return SQLITE_FULL;
  if( pFile->aJrnl==0 || pFile->nJrnl<iEnd ){
    char *aNew = sqlite3_realloc(pFile->aJrnl, iEnd);
    if( aNew==0 ){
      return SQLITE_IOERR_NOMEM;
    }
    pFile->aJrnl = aNew;
    if( pFile->nJrnl<iOfst ){
      memset(pFile->aJrnl+pFile->nJrnl, 0, iOfst-pFile->nJrnl);
    }
    pFile->nJrnl = iEnd;
  }
  memcpy(pFile->aJrnl+iOfst, zBuf, iAmt);
  return SQLITE_OK;
}

/*
** Write into the database file.
*/
static int kvvfsWriteDb(
  sqlite3_file *pProtoFile,
  const void *zBuf,
  int iAmt,
  sqlite_int64 iOfst
){
  KVVfsFile *pFile = (KVVfsFile*)pProtoFile;
  unsigned int pgno;
  char zKey[30];
  char *aData = pFile->aData;
  SQLITE_KV_LOG(("xWrite('%s-db',%d,%lld)\n", pFile->zClass, iAmt, iOfst));
  assert( iAmt>=512 && iAmt<=65536 );
  assert( (iAmt & (iAmt-1))==0 );
  assert( pFile->szPage<0 || pFile->szPage==iAmt );
  pFile->szPage = iAmt;
  pgno = 1 + iOfst/iAmt;
  sqlite3_snprintf(sizeof(zKey), zKey, "%u", pgno);
  kvvfsEncode(zBuf, iAmt, aData);
  if( sqlite3KvvfsMethods.xWrite(pFile->zClass, zKey, aData) ){
    return SQLITE_IOERR;
  }
  if( iOfst+iAmt > pFile->szDb ){
    pFile->szDb = iOfst + iAmt;
  }
  return SQLITE_OK;
}

/*
** Truncate an kvvfs-file.
*/
static int kvvfsTruncateJrnl(sqlite3_file *pProtoFile, sqlite_int64 size){
  KVVfsFile *pFile = (KVVfsFile *)pProtoFile;
  SQLITE_KV_LOG(("xTruncate('%s-journal',%lld)\n", pFile->zClass, size));
  assert( size==0 );
  sqlite3KvvfsMethods.xDelete(pFile->zClass, "jrnl");
  sqlite3_free(pFile->aJrnl);
  pFile->aJrnl = 0;
  pFile->nJrnl = 0;
  return SQLITE_OK;
}
static int kvvfsTruncateDb(sqlite3_file *pProtoFile, sqlite_int64 size){
  KVVfsFile *pFile = (KVVfsFile *)pProtoFile;
  if( pFile->szDb>size
   && pFile->szPage>0
   && (size % pFile->szPage)==0
  ){
    char zKey[50];
    unsigned int pgno, pgnoMax;
    SQLITE_KV_LOG(("xTruncate('%s-db',%lld)\n", pFile->zClass, size));
    pgno = 1 + size/pFile->szPage;
    pgnoMax = 2 + pFile->szDb/pFile->szPage;
    while( pgno<=pgnoMax ){
      sqlite3_snprintf(sizeof(zKey), zKey, "%u", pgno);
      sqlite3KvvfsMethods.xDelete(pFile->zClass, zKey);
      pgno++;
    }
    pFile->szDb = size;
    return kvvfsWriteFileSize(pFile, size) ? SQLITE_IOERR : SQLITE_OK;
  }
  return SQLITE_IOERR;
}

/*
** Sync an kvvfs-file.
*/
static int kvvfsSyncJrnl(sqlite3_file *pProtoFile, int flags){
  int i, n;
  KVVfsFile *pFile = (KVVfsFile *)pProtoFile;
  char *zOut;
  SQLITE_KV_LOG(("xSync('%s-journal')\n", pFile->zClass));
  if( pFile->nJrnl<=0 ){
    return kvvfsTruncateJrnl(pProtoFile, 0);
  }
  zOut = sqlite3_malloc64( pFile->nJrnl*2 + 50 );
  if( zOut==0 ){
    return SQLITE_IOERR_NOMEM;
  }
  n = pFile->nJrnl;
  i = 0;
  do{
    zOut[i++] = 'a' + (n%26);
    n /= 26;
  }while( n>0 );
  zOut[i++] = ' ';
  kvvfsEncode(pFile->aJrnl, pFile->nJrnl, &zOut[i]);
  i = sqlite3KvvfsMethods.xWrite(pFile->zClass, "jrnl", zOut);
  sqlite3_free(zOut);
  return i ? SQLITE_IOERR : SQLITE_OK;
}
static int kvvfsSyncDb(sqlite3_file *pProtoFile, int flags){
  return SQLITE_OK;
}

/*
** Return the current file-size of an kvvfs-file.
*/
static int kvvfsFileSizeJrnl(sqlite3_file *pProtoFile, sqlite_int64 *pSize){
  KVVfsFile *pFile = (KVVfsFile *)pProtoFile;
  SQLITE_KV_LOG(("xFileSize('%s-journal')\n", pFile->zClass));
  *pSize = pFile->nJrnl;
  return SQLITE_OK;
}
static int kvvfsFileSizeDb(sqlite3_file *pProtoFile, sqlite_int64 *pSize){
  KVVfsFile *pFile = (KVVfsFile *)pProtoFile;
  SQLITE_KV_LOG(("xFileSize('%s-db')\n", pFile->zClass));
  if( pFile->szDb>=0 ){
    *pSize = pFile->szDb;
  }else{
    *pSize = kvvfsReadFileSize(pFile);
  }
  return SQLITE_OK;
}

/*
** Lock an kvvfs-file.
*/
static int kvvfsLock(sqlite3_file *pProtoFile, int eLock){
  KVVfsFile *pFile = (KVVfsFile *)pProtoFile;
  assert( !pFile->isJournal );
  SQLITE_KV_LOG(("xLock(%s,%d)\n", pFile->zClass, eLock));

  if( eLock!=SQLITE_LOCK_NONE ){
    pFile->szDb = kvvfsReadFileSize(pFile);
  }
  return SQLITE_OK;
}

/*
** Unlock an kvvfs-file.
*/
static int kvvfsUnlock(sqlite3_file *pProtoFile, int eLock){
  KVVfsFile *pFile = (KVVfsFile *)pProtoFile;
  assert( !pFile->isJournal );
  SQLITE_KV_LOG(("xUnlock(%s,%d)\n", pFile->zClass, eLock));
  if( eLock==SQLITE_LOCK_NONE ){
    pFile->szDb = -1;
  }
  return SQLITE_OK;
}

/*
** Check if another file-handle holds a RESERVED lock on an kvvfs-file.
*/
static int kvvfsCheckReservedLock(sqlite3_file *pProtoFile, int *pResOut){
  SQLITE_KV_LOG(("xCheckReservedLock\n"));
  *pResOut = 0;
  return SQLITE_OK;
}

/*
** File control method. For custom operations on an kvvfs-file.
*/
static int kvvfsFileControlJrnl(sqlite3_file *pProtoFile, int op, void *pArg){
  SQLITE_KV_LOG(("xFileControl(%d) on journal\n", op));
  return SQLITE_NOTFOUND;
}
static int kvvfsFileControlDb(sqlite3_file *pProtoFile, int op, void *pArg){
  SQLITE_KV_LOG(("xFileControl(%d) on database\n", op));
  if( op==SQLITE_FCNTL_SYNC ){
    KVVfsFile *pFile = (KVVfsFile *)pProtoFile;
    int rc = SQLITE_OK;
    SQLITE_KV_LOG(("xSync('%s-db')\n", pFile->zClass));
    if( pFile->szDb>0 && 0!=kvvfsWriteFileSize(pFile, pFile->szDb) ){
      rc = SQLITE_IOERR;
    }
    return rc;
  }
  return SQLITE_NOTFOUND;
}

/*
** Return the sector-size in bytes for an kvvfs-file.
*/
static int kvvfsSectorSize(sqlite3_file *pFile){
  return 512;
}

/*
** Return the device characteristic flags supported by an kvvfs-file.
*/
static int kvvfsDeviceCharacteristics(sqlite3_file *pProtoFile){
  return 0;
}

/****** sqlite3_vfs methods *************************************************/

/*
** Open an kvvfs file handle.
*/
static int kvvfsOpen(
  sqlite3_vfs *pProtoVfs,
  const char *zName,
  sqlite3_file *pProtoFile,
  int flags,
  int *pOutFlags
){
  KVVfsFile *pFile = (KVVfsFile*)pProtoFile;
  if( zName==0 ) zName = "";
  SQLITE_KV_LOG(("xOpen(\"%s\")\n", zName));
  if( strcmp(zName, "local")==0
   || strcmp(zName, "session")==0
  ){
    pFile->isJournal = 0;
    pFile->base.pMethods = &kvvfs_db_io_methods;
  }else
  if( strcmp(zName, "local-journal")==0
   || strcmp(zName, "session-journal")==0
  ){
    pFile->isJournal = 1;
    pFile->base.pMethods = &kvvfs_jrnl_io_methods;
  }else{
    return SQLITE_CANTOPEN;
  }
  if( zName[0]=='s' ){
    pFile->zClass = "session";
  }else{
    pFile->zClass = "local";
  }
  pFile->aData = sqlite3_malloc64(SQLITE_KVOS_SZ);
  if( pFile->aData==0 ){
    return SQLITE_NOMEM;
  }
  pFile->aJrnl = 0;
  pFile->nJrnl = 0;
  pFile->szPage = -1;
  pFile->szDb = -1;
  return SQLITE_OK;
}

/*
** Delete the file located at zPath. If the dirSync argument is true,
** ensure the file-system modifications are synced to disk before
** returning.
*/
static int kvvfsDelete(sqlite3_vfs *pVfs, const char *zPath, int dirSync){
  if( strcmp(zPath, "local-journal")==0 ){
    sqlite3KvvfsMethods.xDelete("local", "jrnl");
  }else
  if( strcmp(zPath, "session-journal")==0 ){
    sqlite3KvvfsMethods.xDelete("session", "jrnl");
  }
  return SQLITE_OK;
}

/*
** Test for access permissions. Return true if the requested permission
** is available, or false otherwise.
*/
static int kvvfsAccess(
  sqlite3_vfs *pProtoVfs,
  const char *zPath,
  int flags,
  int *pResOut
){
  SQLITE_KV_LOG(("xAccess(\"%s\")\n", zPath));
  if( strcmp(zPath, "local-journal")==0 ){
    *pResOut = sqlite3KvvfsMethods.xRead("local", "jrnl", 0, 0)>0;
  }else
  if( strcmp(zPath, "session-journal")==0 ){
    *pResOut = sqlite3KvvfsMethods.xRead("session", "jrnl", 0, 0)>0;
  }else
  if( strcmp(zPath, "local")==0 ){
    *pResOut = sqlite3KvvfsMethods.xRead("local", "sz", 0, 0)>0;
  }else
  if( strcmp(zPath, "session")==0 ){
    *pResOut = sqlite3KvvfsMethods.xRead("session", "sz", 0, 0)>0;
  }else
  {
    *pResOut = 0;
  }
  SQLITE_KV_LOG(("xAccess returns %d\n",*pResOut));
  return SQLITE_OK;
}

/*
** Populate buffer zOut with the full canonical pathname corresponding
** to the pathname in zPath. zOut is guaranteed to point to a buffer
** of at least (INST_MAX_PATHNAME+1) bytes.
*/
static int kvvfsFullPathname(
  sqlite3_vfs *pVfs,
  const char *zPath,
  int nOut,
  char *zOut
){
  size_t nPath;
#ifdef SQLITE_OS_KV_ALWAYS_LOCAL
  zPath = "local";
#endif
  nPath = strlen(zPath);
  SQLITE_KV_LOG(("xFullPathname(\"%s\")\n", zPath));
  if( nOut<nPath+1 ) nPath = nOut - 1;
  memcpy(zOut, zPath, nPath);
  zOut[nPath] = 0;
  return SQLITE_OK;
}

/*
** Open the dynamic library located at zPath and return a handle.
*/
static void *kvvfsDlOpen(sqlite3_vfs *pVfs, const char *zPath){
  return 0;
}

/*
** Populate the buffer pointed to by zBufOut with nByte bytes of
** random data.
*/
static int kvvfsRandomness(sqlite3_vfs *pVfs, int nByte, char *zBufOut){
  memset(zBufOut, 0, nByte);
  return nByte;
}

/*
** Sleep for nMicro microseconds. Return the number of microseconds
** actually slept.
*/
static int kvvfsSleep(sqlite3_vfs *pVfs, int nMicro){
  return SQLITE_OK;
}

/*
** Return the current time as a Julian Day number in *pTimeOut.
*/
static int kvvfsCurrentTime(sqlite3_vfs *pVfs, double *pTimeOut){
  sqlite3_int64 i = 0;
  int rc;
  rc = kvvfsCurrentTimeInt64(0, &i);
  *pTimeOut = i/86400000.0;
  return rc;
}
#include <sys/time.h>
static int kvvfsCurrentTimeInt64(sqlite3_vfs *pVfs, sqlite3_int64 *pTimeOut){
  static const sqlite3_int64 unixEpoch = 24405875*(sqlite3_int64)8640000;
  struct timeval sNow;
  (void)gettimeofday(&sNow, 0);  /* Cannot fail given valid arguments */
  *pTimeOut = unixEpoch + 1000*(sqlite3_int64)sNow.tv_sec + sNow.tv_usec/1000;
  return SQLITE_OK;
}
#endif /* SQLITE_OS_KV || SQLITE_OS_UNIX */

#if SQLITE_OS_KV
/*
** This routine is called initialize the KV-vfs as the default VFS.
*/
SQLITE_API int sqlite3_os_init(void){
  return sqlite3_vfs_register(&sqlite3OsKvvfsObject, 1);
}
SQLITE_API int sqlite3_os_end(void){
  return SQLITE_OK;
}
#endif /* SQLITE_OS_KV */

#if SQLITE_OS_UNIX && defined(SQLITE_OS_KV_OPTIONAL)
SQLITE_PRIVATE int sqlite3KvvfsInit(void){
  return sqlite3_vfs_register(&sqlite3OsKvvfsObject, 0);
}
#endif

/************** End of os_kv.c ***********************************************/
/************** Begin file os_unix.c *****************************************/
/*
** 2004 May 22
**
** The author disclaims copyright to this source code.  In place of
** a legal notice, here is a blessing:
**

# undef USE_PREAD64
# define USE_PREAD 1
#endif

/*
** standard include files.
*/
#include <sys/types.h>   /* amalgamator: keep */
#include <sys/stat.h>    /* amalgamator: keep */
#include <fcntl.h>
#include <sys/ioctl.h>
#include <unistd.h>      /* amalgamator: keep */
/* #include <time.h> */
#include <sys/time.h>    /* amalgamator: keep */
#include <errno.h>
#if !defined(SQLITE_OMIT_WAL) || SQLITE_MAX_MMAP_SIZE>0
# include <sys/mman.h>
#endif

#if SQLITE_ENABLE_LOCKING_STYLE
/* # include <sys/ioctl.h> */

    fd = osOpen(z,f,m2);
#endif
    if( fd<0 ){
      if( errno==EINTR ) continue;
      break;
    }
    if( fd>=SQLITE_MINIMUM_FILE_DESCRIPTOR ) break;
    if( (f & (O_EXCL|O_CREAT))==(O_EXCL|O_CREAT) ){
      (void)osUnlink(z);
    }
    osClose(fd);
    sqlite3_log(SQLITE_WARNING,
                "attempt to open \"%s\" as file descriptor %d", z, fd);
    fd = -1;
    if( osOpen("/dev/null", O_RDONLY, m)<0 ) break;
  }
  if( fd>=0 ){

** are inserted in between.  The locking might fail on one of the later
** transitions leaving the lock state different from what it started but
** still short of its goal.  The following chart shows the allowed
** transitions and the inserted intermediate states:
**
**    UNLOCKED -> SHARED
**    SHARED -> RESERVED
**    SHARED -> EXCLUSIVE
**    RESERVED -> (PENDING) -> EXCLUSIVE
**    PENDING -> EXCLUSIVE
**
** This routine will only increase a lock.  Use the sqlite3OsUnlock()
** routine to lower a locking level.
*/
static int unixLock(sqlite3_file *id, int eFileLock){

  ** lack of shared-locks on Windows95 lives on, for backwards
  ** compatibility.)
  **
  ** A process may only obtain a RESERVED lock after it has a SHARED lock.
  ** A RESERVED lock is implemented by grabbing a write-lock on the
  ** 'reserved byte'.
  **
  ** An EXCLUSIVE lock may only be requested after either a SHARED or
  ** RESERVED lock is held. An EXCLUSIVE lock is implemented by obtaining
  ** a write-lock on the entire 'shared byte range'. Since all other locks
  ** require a read-lock on one of the bytes within this range, this ensures
  ** that no other locks are held on the database.



  **
  ** If a process that holds a RESERVED lock requests an EXCLUSIVE, then
  ** a PENDING lock is obtained first. A PENDING lock is implemented by
  ** obtaining a write-lock on the 'pending byte'. This ensures that no new
  ** SHARED locks can be obtained, but existing SHARED locks are allowed to
  ** persist. If the call to this function fails to obtain the EXCLUSIVE
  ** lock in this case, it holds the PENDING lock intead. The client may
  ** then re-attempt the EXCLUSIVE lock later on, after existing SHARED
  ** locks have cleared.
  */
  int rc = SQLITE_OK;
  unixFile *pFile = (unixFile*)id;
  unixInodeInfo *pInode;
  struct flock lock;
  int tErrno = 0;

  /* A PENDING lock is needed before acquiring a SHARED lock and before
  ** acquiring an EXCLUSIVE lock.  For the SHARED lock, the PENDING will
  ** be released.
  */
  lock.l_len = 1L;
  lock.l_whence = SEEK_SET;
  if( eFileLock==SHARED_LOCK
   || (eFileLock==EXCLUSIVE_LOCK && pFile->eFileLock==RESERVED_LOCK)
  ){
    lock.l_type = (eFileLock==SHARED_LOCK?F_RDLCK:F_WRLCK);
    lock.l_start = PENDING_BYTE;
    if( unixFileLock(pFile, &lock) ){
      tErrno = errno;
      rc = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_LOCK);
      if( rc!=SQLITE_BUSY ){
        storeLastErrno(pFile, tErrno);
      }
      goto end_lock;
    }else if( eFileLock==EXCLUSIVE_LOCK ){
      pFile->eFileLock = PENDING_LOCK;
      pInode->eFileLock = PENDING_LOCK;
    }
  }


  /* If control gets to this point, then actually go ahead and make
  ** operating system calls for the specified lock.
  */

   && eFileLock==RESERVED_LOCK
  ){
    pFile->transCntrChng = 0;
    pFile->dbUpdate = 0;
    pFile->inNormalWrite = 1;
  }
#endif


  if( rc==SQLITE_OK ){
    pFile->eFileLock = eFileLock;
    pInode->eFileLock = eFileLock;



  }

end_lock:
  sqlite3_mutex_leave(pInode->pLockMutex);
  OSTRACE(("LOCK    %d %s %s (unix)\n", pFile->h, azFileLock(eFileLock),
      rc==SQLITE_OK ? "ok" : "failed"));
  return rc;

** Create a temporary file name in zBuf.  zBuf must be allocated
** by the calling process and must be big enough to hold at least
** pVfs->mxPathname bytes.
*/
static int unixGetTempname(int nBuf, char *zBuf){
  const char *zDir;
  int iLimit = 0;
  int rc = SQLITE_OK;

  /* It's odd to simulate an io-error here, but really this is just
  ** using the io-error infrastructure to test that SQLite handles this
  ** function failing.
  */
  zBuf[0] = 0;
  SimulateIOError( return SQLITE_IOERR );

  sqlite3_mutex_enter(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_TEMPDIR));
  zDir = unixTempFileDir();
  if( zDir==0 ){
    rc = SQLITE_IOERR_GETTEMPPATH;
  }else{
    do{
      u64 r;
      sqlite3_randomness(sizeof(r), &r);
      assert( nBuf>2 );
      zBuf[nBuf-2] = 0;
      sqlite3_snprintf(nBuf, zBuf, "%s/"SQLITE_TEMP_FILE_PREFIX"%llx%c",
                       zDir, r, 0);
      if( zBuf[nBuf-2]!=0 || (iLimit++)>10 ){
        rc = SQLITE_ERROR;
        break;
      }
    }while( osAccess(zBuf,0)==0 );
  }
  sqlite3_mutex_leave(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_TEMPDIR));
  return rc;
}

#if SQLITE_ENABLE_LOCKING_STYLE && defined(__APPLE__)
/*
** Routine to transform a unixFile into a proxy-locking unixFile.
** Implementation in the proxy-lock division, but used by unixOpen()
** if SQLITE_PREFER_PROXY_LOCKING is defined.

  int nName            /* Number of significant bytes in zName */
){
  assert( nName>0 );
  assert( zName!=0 );
  if( zName[0]=='.' ){
    if( nName==1 ) return;
    if( zName[1]=='.' && nName==2 ){
      if( pPath->nUsed>1 ){



        assert( pPath->zOut[0]=='/' );
        while( pPath->zOut[--pPath->nUsed]!='/' ){}
      }
      return;
    }
  }
  if( pPath->nUsed + nName + 2 >= pPath->nOut ){
    pPath->rc = SQLITE_ERROR;
    return;
  }

** The argument is the number of microseconds we want to sleep.
** The return value is the number of microseconds of sleep actually
** requested from the underlying operating system, a number which
** might be greater than or equal to the argument, but not less
** than the argument.
*/
static int unixSleep(sqlite3_vfs *NotUsed, int microseconds){
#if OS_VXWORKS || _POSIX_C_SOURCE >= 199309L
  struct timespec sp;

  sp.tv_sec = microseconds / 1000000;
  sp.tv_nsec = (microseconds % 1000000) * 1000;
  nanosleep(&sp, NULL);
  UNUSED_PARAMETER(NotUsed);
  return microseconds;

  /* Double-check that the aSyscall[] array has been constructed
  ** correctly.  See ticket [bb3a86e890c8e96ab] */
  assert( ArraySize(aSyscall)==29 );

  /* Register all VFSes defined in the aVfs[] array */
  for(i=0; i<(sizeof(aVfs)/sizeof(sqlite3_vfs)); i++){
#ifdef SQLITE_DEFAULT_UNIX_VFS
    sqlite3_vfs_register(&aVfs[i],
           0==strcmp(aVfs[i].zName,SQLITE_DEFAULT_UNIX_VFS));
#else
    sqlite3_vfs_register(&aVfs[i], i==0);
#endif
  }
#ifdef SQLITE_OS_KV_OPTIONAL
  sqlite3KvvfsInit();
#endif
  unixBigLock = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_VFS1);

#ifndef SQLITE_OMIT_WAL
  /* Validate lock assumptions */
  assert( SQLITE_SHM_NLOCK==8 );  /* Number of available locks */
  assert( UNIX_SHM_BASE==120  );  /* Start of locking area */
  /* Locks:

** it accepts a UTF-8 string.
*/
SQLITE_API int sqlite3_win32_set_directory8(
  unsigned long type, /* Identifier for directory being set or reset */
  const char *zValue  /* New value for directory being set or reset */
){
  char **ppDirectory = 0;
  int rc;
#ifndef SQLITE_OMIT_AUTOINIT
  rc = sqlite3_initialize();
  if( rc ) return rc;
#endif
  sqlite3_mutex_enter(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_TEMPDIR));
  if( type==SQLITE_WIN32_DATA_DIRECTORY_TYPE ){
    ppDirectory = &sqlite3_data_directory;
  }else if( type==SQLITE_WIN32_TEMP_DIRECTORY_TYPE ){
    ppDirectory = &sqlite3_temp_directory;
  }
  assert( !ppDirectory || type==SQLITE_WIN32_DATA_DIRECTORY_TYPE
          || type==SQLITE_WIN32_TEMP_DIRECTORY_TYPE
  );
  assert( !ppDirectory || sqlite3MemdebugHasType(*ppDirectory, MEMTYPE_HEAP) );
  if( ppDirectory ){
    char *zCopy = 0;
    if( zValue && zValue[0] ){
      zCopy = sqlite3_mprintf("%s", zValue);
      if ( zCopy==0 ){
        rc = SQLITE_NOMEM_BKPT;
        goto set_directory8_done;
      }
    }
    sqlite3_free(*ppDirectory);
    *ppDirectory = zCopy;
    rc = SQLITE_OK;
  }else{
    rc = SQLITE_ERROR;
  }
set_directory8_done:
  sqlite3_mutex_leave(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_TEMPDIR));
  return rc;
}

/*
** This function is the same as sqlite3_win32_set_directory (below); however,
** it accepts a UTF-16 string.
*/
SQLITE_API int sqlite3_win32_set_directory16(

        return 1;
      }
    }
  }
  return 0;
}

/*
** If sqlite3_temp_directory is defined, take the mutex and return true.
**
** If sqlite3_temp_directory is NULL (undefined), omit the mutex and
** return false.
*/
static int winTempDirDefined(void){
  sqlite3_mutex_enter(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_TEMPDIR));
  if( sqlite3_temp_directory!=0 ) return 1;
  sqlite3_mutex_leave(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_TEMPDIR));
  return 0;
}

/*
** Create a temporary file name and store the resulting pointer into pzBuf.
** The pointer returned in pzBuf must be freed via sqlite3_free().
*/
static int winGetTempname(sqlite3_vfs *pVfs, char **pzBuf){
  static char zChars[] =
    "abcdefghijklmnopqrstuvwxyz"

  /* Figure out the effective temporary directory.  First, check if one
  ** has been explicitly set by the application; otherwise, use the one
  ** configured by the operating system.
  */
  nDir = nMax - (nPre + 15);
  assert( nDir>0 );
  if( winTempDirDefined() ){
    int nDirLen = sqlite3Strlen30(sqlite3_temp_directory);
    if( nDirLen>0 ){
      if( !winIsDirSep(sqlite3_temp_directory[nDirLen-1]) ){
        nDirLen++;
      }
      if( nDirLen>nDir ){
        sqlite3_mutex_leave(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_TEMPDIR));
        sqlite3_free(zBuf);
        OSTRACE(("TEMP-FILENAME rc=SQLITE_ERROR\n"));
        return winLogError(SQLITE_ERROR, 0, "winGetTempname1", 0);
      }
      sqlite3_snprintf(nMax, zBuf, "%s", sqlite3_temp_directory);
    }
    sqlite3_mutex_leave(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_TEMPDIR));
  }

#if defined(__CYGWIN__)
  else{
    static const char *azDirs[] = {
       0, /* getenv("SQLITE_TMPDIR") */
       0, /* getenv("TMPDIR") */
       0, /* getenv("TMP") */
       0, /* getenv("TEMP") */

}

/*
** Turn a relative pathname into a full pathname.  Write the full
** pathname into zOut[].  zOut[] will be at least pVfs->mxPathname
** bytes in size.
*/
static int winFullPathnameNoMutex(
  sqlite3_vfs *pVfs,            /* Pointer to vfs object */
  const char *zRelative,        /* Possibly relative input path */
  int nFull,                    /* Size of output buffer in bytes */
  char *zFull                   /* Output buffer */
){
#if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT && !defined(__CYGWIN__)
  DWORD nByte;

    sqlite3_free(zOut);
    return SQLITE_OK;
  }else{
    return SQLITE_IOERR_NOMEM_BKPT;
  }
#endif
}
static int winFullPathname(
  sqlite3_vfs *pVfs,            /* Pointer to vfs object */
  const char *zRelative,        /* Possibly relative input path */
  int nFull,                    /* Size of output buffer in bytes */
  char *zFull                   /* Output buffer */
){
  int rc;
  MUTEX_LOGIC( sqlite3_mutex *pMutex; )
  MUTEX_LOGIC( pMutex = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_TEMPDIR); )
  sqlite3_mutex_enter(pMutex);
  rc = winFullPathnameNoMutex(pVfs, zRelative, nFull, zFull);
  sqlite3_mutex_leave(pMutex);
  return rc;
}

#ifndef SQLITE_OMIT_LOAD_EXTENSION
/*
** Interfaces for opening a shared library, finding entry points
** within the shared library, and closing the shared library.
*/
static void *winDlOpen(sqlite3_vfs *pVfs, const char *zFilename){

static int memdbClose(sqlite3_file*);
static int memdbRead(sqlite3_file*, void*, int iAmt, sqlite3_int64 iOfst);
static int memdbWrite(sqlite3_file*,const void*,int iAmt, sqlite3_int64 iOfst);
static int memdbTruncate(sqlite3_file*, sqlite3_int64 size);
static int memdbSync(sqlite3_file*, int flags);
static int memdbFileSize(sqlite3_file*, sqlite3_int64 *pSize);
static int memdbLock(sqlite3_file*, int);
static int memdbUnlock(sqlite3_file*, int);
/* static int memdbCheckReservedLock(sqlite3_file*, int *pResOut);// not used */
static int memdbFileControl(sqlite3_file*, int op, void *pArg);
/* static int memdbSectorSize(sqlite3_file*); // not used */
static int memdbDeviceCharacteristics(sqlite3_file*);
static int memdbFetch(sqlite3_file*, sqlite3_int64 iOfst, int iAmt, void **pp);
static int memdbUnfetch(sqlite3_file*, sqlite3_int64 iOfst, void *p);

  memdbClose,                      /* xClose */
  memdbRead,                       /* xRead */
  memdbWrite,                      /* xWrite */
  memdbTruncate,                   /* xTruncate */
  memdbSync,                       /* xSync */
  memdbFileSize,                   /* xFileSize */
  memdbLock,                       /* xLock */
  memdbUnlock,                     /* xUnlock */
  0, /* memdbCheckReservedLock, */ /* xCheckReservedLock */
  memdbFileControl,                /* xFileControl */
  0, /* memdbSectorSize,*/         /* xSectorSize */
  memdbDeviceCharacteristics,      /* xDeviceCharacteristics */
  0,                               /* xShmMap */
  0,                               /* xShmLock */
  0,                               /* xShmBarrier */

/*
** Lock an memdb-file.
*/
static int memdbLock(sqlite3_file *pFile, int eLock){
  MemFile *pThis = (MemFile*)pFile;
  MemStore *p = pThis->pStore;
  int rc = SQLITE_OK;
  if( eLock<=pThis->eLock ) return SQLITE_OK;
  memdbEnter(p);

  assert( p->nWrLock==0 || p->nWrLock==1 );
  assert( pThis->eLock<=SQLITE_LOCK_SHARED || p->nWrLock==1 );
  assert( pThis->eLock==SQLITE_LOCK_NONE || p->nRdLock>=1 );

  if( eLock>SQLITE_LOCK_SHARED && (p->mFlags & SQLITE_DESERIALIZE_READONLY) ){
    rc = SQLITE_READONLY;
  }else{
    switch( eLock ){
      case SQLITE_LOCK_SHARED: {
        assert( pThis->eLock==SQLITE_LOCK_NONE );
        if( p->nWrLock>0 ){
          rc = SQLITE_BUSY;
        }else{
          p->nRdLock++;
        }
        break;
      };

      case SQLITE_LOCK_RESERVED:
      case SQLITE_LOCK_PENDING: {
        assert( pThis->eLock>=SQLITE_LOCK_SHARED );
        if( ALWAYS(pThis->eLock==SQLITE_LOCK_SHARED) ){
          if( p->nWrLock>0 ){
            rc = SQLITE_BUSY;
          }else{
            p->nWrLock = 1;
          }
        }
        break;
      }

      default: {
        assert(  eLock==SQLITE_LOCK_EXCLUSIVE );
        assert( pThis->eLock>=SQLITE_LOCK_SHARED );
        if( p->nRdLock>1 ){
          rc = SQLITE_BUSY;
        }else if( pThis->eLock==SQLITE_LOCK_SHARED ){
          p->nWrLock = 1;
        }

        break;
      }
    }
  }
  if( rc==SQLITE_OK ) pThis->eLock = eLock;
  memdbLeave(p);
  return rc;
}

/*
** Unlock an memdb-file.
*/
static int memdbUnlock(sqlite3_file *pFile, int eLock){
  MemFile *pThis = (MemFile*)pFile;
  MemStore *p = pThis->pStore;
  if( eLock>=pThis->eLock ) return SQLITE_OK;
  memdbEnter(p);

  assert( eLock==SQLITE_LOCK_SHARED || eLock==SQLITE_LOCK_NONE );
  if( eLock==SQLITE_LOCK_SHARED ){
    if( ALWAYS(pThis->eLock>SQLITE_LOCK_SHARED) ){
      p->nWrLock--;
    }
  }else{
    if( pThis->eLock>SQLITE_LOCK_SHARED ){
      p->nWrLock--;
    }
    p->nRdLock--;
  }

  pThis->eLock = eLock;
  memdbLeave(p);
  return SQLITE_OK;
}

#if 0
/*
** This interface is only used for crash recovery, which does not
** occur on an in-memory database.
*/
static int memdbCheckReservedLock(sqlite3_file *pFile, int *pResOut){
  *pResOut = 0;

  MemFile *pFile = (MemFile*)pFd;
  MemStore *p = 0;
  int szName;
  UNUSED_PARAMETER(pVfs);

  memset(pFile, 0, sizeof(*pFile));
  szName = sqlite3Strlen30(zName);
  if( szName>1 && (zName[0]=='/' || zName[0]=='\\') ){
    int i;
#ifndef SQLITE_MUTEX_OMIT
    sqlite3_mutex *pVfsMutex = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_VFS1);
#endif
    sqlite3_mutex_enter(pVfsMutex);
    for(i=0; i<memdb_g.nMemStore; i++){
      if( strcmp(memdb_g.apMemStore[i]->zFName,zName)==0 ){

  if( pData && (mFlags & SQLITE_DESERIALIZE_FREEONCLOSE)!=0 ){
    sqlite3_free(pData);
  }
  sqlite3_mutex_leave(db->mutex);
  return rc;
}

/*
** Return true if the VFS is the memvfs.
*/
SQLITE_PRIVATE int sqlite3IsMemdb(const sqlite3_vfs *pVfs){
  return pVfs==&memdb_vfs;
}

/*
** This routine is called when the extension is loaded.
** Register the new VFS.
*/
SQLITE_PRIVATE int sqlite3MemdbInit(void){
  sqlite3_vfs *pLower = sqlite3_vfs_find(0);
  unsigned int sz;

** When sqlite3PcacheTrace is 2, a dump of the pcache showing all cache entries
** is displayed for many operations, resulting in a lot of output.
*/
#if defined(SQLITE_DEBUG) && 0
  int sqlite3PcacheTrace = 2;       /* 0: off  1: simple  2: cache dumps */
  int sqlite3PcacheMxDump = 9999;   /* Max cache entries for pcacheDump() */
# define pcacheTrace(X) if(sqlite3PcacheTrace){sqlite3DebugPrintf X;}
  static void pcachePageTrace(int i, sqlite3_pcache_page *pLower){
    PgHdr *pPg;
    unsigned char *a;
    int j;
    pPg = (PgHdr*)pLower->pExtra;
    printf("%3d: nRef %2d flgs %02x data ", i, pPg->nRef, pPg->flags);
    a = (unsigned char *)pLower->pBuf;
    for(j=0; j<12; j++) printf("%02x", a[j]);
    printf(" ptr %p\n", pPg);
  }
  static void pcacheDump(PCache *pCache){
    int N;
    int i;
    sqlite3_pcache_page *pLower;



    if( sqlite3PcacheTrace<2 ) return;
    if( pCache->pCache==0 ) return;
    N = sqlite3PcachePagecount(pCache);
    if( N>sqlite3PcacheMxDump ) N = sqlite3PcacheMxDump;
    for(i=1; i<=N; i++){
       pLower = sqlite3GlobalConfig.pcache2.xFetch(pCache->pCache, i, 0);
       if( pLower==0 ) continue;


       pcachePageTrace(i, pLower);


       if( ((PgHdr*)pLower)->pPage==0 ){
         sqlite3GlobalConfig.pcache2.xUnpin(pCache->pCache, pLower, 0);
       }
    }
  }
#else
# define pcacheTrace(X)
# define pcachePageTrace(PGNO, X)
# define pcacheDump(X)
#endif

/*
** Return 1 if pPg is on the dirty list for pCache.  Return 0 if not.
** This routine runs inside of assert() statements only.
*/
#ifdef SQLITE_DEBUG
static int pageOnDirtyList(PCache *pCache, PgHdr *pPg){
  PgHdr *p;
  for(p=pCache->pDirty; p; p=p->pDirtyNext){
    if( p==pPg ) return 1;
  }
  return 0;
}
#endif

/*
** Check invariants on a PgHdr entry.  Return true if everything is OK.
** Return false if any invariant is violated.
**
** This routine is for use inside of assert() statements only.  For
** example:
**
**          assert( sqlite3PcachePageSanity(pPg) );
*/
#ifdef SQLITE_DEBUG
SQLITE_PRIVATE int sqlite3PcachePageSanity(PgHdr *pPg){
  PCache *pCache;
  assert( pPg!=0 );
  assert( pPg->pgno>0 || pPg->pPager==0 );    /* Page number is 1 or more */
  pCache = pPg->pCache;
  assert( pCache!=0 );      /* Every page has an associated PCache */
  if( pPg->flags & PGHDR_CLEAN ){
    assert( (pPg->flags & PGHDR_DIRTY)==0 );/* Cannot be both CLEAN and DIRTY */
    assert( !pageOnDirtyList(pCache, pPg) );/* CLEAN pages not on dirty list */
  }else{
    assert( (pPg->flags & PGHDR_DIRTY)!=0 );/* If not CLEAN must be DIRTY */
    assert( pPg->pDirtyNext==0 || pPg->pDirtyNext->pDirtyPrev==pPg );
    assert( pPg->pDirtyPrev==0 || pPg->pDirtyPrev->pDirtyNext==pPg );
    assert( pPg->pDirtyPrev!=0 || pCache->pDirty==pPg );
    assert( pageOnDirtyList(pCache, pPg) );
  }
  /* WRITEABLE pages must also be DIRTY */
  if( pPg->flags & PGHDR_WRITEABLE ){
    assert( pPg->flags & PGHDR_DIRTY );     /* WRITEABLE implies DIRTY */
  }
  /* NEED_SYNC can be set independently of WRITEABLE.  This can happen,
  ** for example, when using the sqlite3PagerDontWrite() optimization:

  **          (createFlag==1 AND !(bPurgeable AND pDirty)
  */
  eCreate = createFlag & pCache->eCreate;
  assert( eCreate==0 || eCreate==1 || eCreate==2 );
  assert( createFlag==0 || pCache->eCreate==eCreate );
  assert( createFlag==0 || eCreate==1+(!pCache->bPurgeable||!pCache->pDirty) );
  pRes = sqlite3GlobalConfig.pcache2.xFetch(pCache->pCache, pgno, eCreate);
  pcacheTrace(("%p.FETCH %d%s (result: %p) ",pCache,pgno,
               createFlag?" create":"",pRes));
  pcachePageTrace(pgno, pRes);
  return pRes;
}

/*
** If the sqlite3PcacheFetch() routine is unable to allocate a new
** page because no clean pages are available for reuse and the cache
** size limit has been reached, then this routine can be invoked to

  assert( p->nRef>0 );
  p->pCache->nRefSum--;
  if( (--p->nRef)==0 ){
    if( p->flags&PGHDR_CLEAN ){
      pcacheUnpin(p);
    }else{
      pcacheManageDirtyList(p, PCACHE_DIRTYLIST_FRONT);
      assert( sqlite3PcachePageSanity(p) );
    }
  }
}

/*
** Increase the reference count of a supplied page by 1.
*/

  if( p->flags & (PGHDR_CLEAN|PGHDR_DONT_WRITE) ){    /*OPTIMIZATION-IF-FALSE*/
    p->flags &= ~PGHDR_DONT_WRITE;
    if( p->flags & PGHDR_CLEAN ){
      p->flags ^= (PGHDR_DIRTY|PGHDR_CLEAN);
      pcacheTrace(("%p.DIRTY %d\n",p->pCache,p->pgno));
      assert( (p->flags & (PGHDR_DIRTY|PGHDR_CLEAN))==PGHDR_DIRTY );
      pcacheManageDirtyList(p, PCACHE_DIRTYLIST_ADD);
      assert( sqlite3PcachePageSanity(p) );
    }
    assert( sqlite3PcachePageSanity(p) );
  }
}

/*
** Make sure the page is marked as clean. If it isn't clean already,

}

/*
** Change the page number of page p to newPgno.
*/
SQLITE_PRIVATE void sqlite3PcacheMove(PgHdr *p, Pgno newPgno){
  PCache *pCache = p->pCache;
  sqlite3_pcache_page *pOther;
  assert( p->nRef>0 );
  assert( newPgno>0 );
  assert( sqlite3PcachePageSanity(p) );
  pcacheTrace(("%p.MOVE %d -> %d\n",pCache,p->pgno,newPgno));
  pOther = sqlite3GlobalConfig.pcache2.xFetch(pCache->pCache, newPgno, 0);
  if( pOther ){
    PgHdr *pXPage = (PgHdr*)pOther->pExtra;
    assert( pXPage->nRef==0 );
    pXPage->nRef++;
    pCache->nRefSum++;
    sqlite3PcacheDrop(pXPage);
  }
  sqlite3GlobalConfig.pcache2.xRekey(pCache->pCache, p->pPage, p->pgno,newPgno);
  p->pgno = newPgno;
  if( (p->flags&PGHDR_DIRTY) && (p->flags&PGHDR_NEED_SYNC) ){
    pcacheManageDirtyList(p, PCACHE_DIRTYLIST_FRONT);
    assert( sqlite3PcachePageSanity(p) );
  }
}

/*
** Drop every cache entry whose page number is greater than "pgno". The
** caller must ensure that there are no outstanding references to any pages
** other than page 1 with a page number greater than pgno.

**
** The size of the extension (MemPage+PgHdr+PgHdr1) can be determined at
** runtime using sqlite3_config(SQLITE_CONFIG_PCACHE_HDRSZ, &size).  The
** sizes of the extensions sum to 272 bytes on x64 for 3.8.10, but this
** size can vary according to architecture, compile-time options, and
** SQLite library version number.
**
** Historical note:  It used to be that if the SQLITE_PCACHE_SEPARATE_HEADER
** was defined, then the page content would be held in a separate memory
** allocation from the PgHdr1.  This was intended to avoid clownshoe memory
** allocations.  However, the btree layer needs a small (16-byte) overrun
** area after the page content buffer.  The header serves as that overrun
** area.  Therefore SQLITE_PCACHE_SEPARATE_HEADER was discontinued to avoid
** any possibility of a memory error.

**
** This module tracks pointers to PgHdr1 objects.  Only pcache.c communicates
** with this module.  Information is passed back and forth as PgHdr1 pointers.
**
** The pcache.c and pager.c modules deal pointers to PgHdr objects.
** The btree.c module deals with pointers to MemPage objects.
**

typedef struct PCache1 PCache1;
typedef struct PgHdr1 PgHdr1;
typedef struct PgFreeslot PgFreeslot;
typedef struct PGroup PGroup;

/*
** Each cache entry is represented by an instance of the following

** structure. A buffer of PgHdr1.pCache->szPage bytes is allocated
** directly before this structure and is used to cache the page content.
**
** When reading a corrupt database file, it is possible that SQLite might
** read a few bytes (no more than 16 bytes) past the end of the page buffer.
** It will only read past the end of the page buffer, never write.  This
** object is positioned immediately after the page buffer to serve as an
** overrun area, so that overreads are harmless.
**
** Variables isBulkLocal and isAnchor were once type "u8". That works,
** but causes a 2-byte gap in the structure for most architectures (since
** pointers must be either 4 or 8-byte aligned). As this structure is located
** in memory directly after the associated page data, if the database is
** corrupt, code at the b-tree layer may overread the page buffer and
** read part of this structure before the corruption is detected. This
** can cause a valgrind error if the unitialized gap is accessed. Using u16
** ensures there is no such gap, and therefore no bytes of uninitialized
** memory in the structure.
**
** The pLruNext and pLruPrev pointers form a double-linked circular list
** of all pages that are unpinned.  The PGroup.lru element (which should be
** the only element on the list with PgHdr1.isAnchor set to 1) forms the
** beginning and the end of the list.
*/
struct PgHdr1 {
  sqlite3_pcache_page page; /* Base class. Must be first. pBuf & pExtra */
  unsigned int iKey;        /* Key value (page number) */
  u16 isBulkLocal;          /* This page from bulk local storage */
  u16 isAnchor;             /* This is the PGroup.lru element */
  PgHdr1 *pNext;            /* Next in hash table chain */
  PCache1 *pCache;          /* Cache that currently owns this page */
  PgHdr1 *pLruNext;         /* Next in circular LRU list of unpinned pages */
  PgHdr1 *pLruPrev;         /* Previous in LRU list of unpinned pages */
                            /* NB: pLruPrev is only valid if pLruNext!=0 */
};

/*
** A page is pinned if it is not on the LRU list.  To be "pinned" means
** that the page is in active use and must not be deallocated.
*/
#define PAGE_IS_PINNED(p)    ((p)->pLruNext==0)

    ** is because it might call sqlite3_release_memory(), which assumes that
    ** this mutex is not held. */
    assert( pcache1.separateCache==0 );
    assert( pCache->pGroup==&pcache1.grp );
    pcache1LeaveMutex(pCache->pGroup);
#endif
    if( benignMalloc ){ sqlite3BeginBenignMalloc(); }









    pPg = pcache1Alloc(pCache->szAlloc);

    if( benignMalloc ){ sqlite3EndBenignMalloc(); }
#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
    pcache1EnterMutex(pCache->pGroup);
#endif
    if( pPg==0 ) return 0;

    p = (PgHdr1 *)&((u8 *)pPg)[pCache->szPage];

    p->page.pBuf = pPg;
    p->page.pExtra = &p[1];
    p->isBulkLocal = 0;
    p->isAnchor = 0;
    p->pLruPrev = 0;           /* Initializing this saves a valgrind error */
  }
  (*pCache->pnPurgeable)++;

  pCache = p->pCache;
  assert( sqlite3_mutex_held(p->pCache->pGroup->mutex) );
  if( p->isBulkLocal ){
    p->pNext = pCache->pFree;
    pCache->pFree = p;
  }else{
    pcache1Free(p->page.pBuf);



  }
  (*pCache->pnPurgeable)--;
}

/*
** Malloc function used by SQLite to obtain space from the buffer configured
** using sqlite3_config(SQLITE_CONFIG_PAGECACHE) option. If no such buffer

  sqlite3_pcache_page *pPg,
  unsigned int iOld,
  unsigned int iNew
){
  PCache1 *pCache = (PCache1 *)p;
  PgHdr1 *pPage = (PgHdr1 *)pPg;
  PgHdr1 **pp;
  unsigned int hOld, hNew;
  assert( pPage->iKey==iOld );
  assert( pPage->pCache==pCache );
  assert( iOld!=iNew );               /* The page number really is changing */

  pcache1EnterMutex(pCache->pGroup);

  assert( pcache1FetchNoMutex(p, iOld, 0)==pPage ); /* pPg really is iOld */
  hOld = iOld%pCache->nHash;
  pp = &pCache->apHash[hOld];
  while( (*pp)!=pPage ){
    pp = &(*pp)->pNext;
  }
  *pp = pPage->pNext;

  assert( pcache1FetchNoMutex(p, iNew, 0)==0 ); /* iNew not in cache */
  hNew = iNew%pCache->nHash;
  pPage->iKey = iNew;
  pPage->pNext = pCache->apHash[hNew];
  pCache->apHash[hNew] = pPage;
  if( iNew>pCache->iMaxKey ){
    pCache->iMaxKey = iNew;
  }

  pcache1LeaveMutex(pCache->pGroup);
}

    PgHdr1 *p;
    pcache1EnterMutex(&pcache1.grp);
    while( (nReq<0 || nFree<nReq)
       &&  (p=pcache1.grp.lru.pLruPrev)!=0
       &&  p->isAnchor==0
    ){
      nFree += pcache1MemSize(p->page.pBuf);



      assert( PAGE_IS_UNPINNED(p) );
      pcache1PinPage(p);
      pcache1RemoveFromHash(p, 1);
    }
    pcache1LeaveMutex(&pcache1.grp);
  }
  return nFree;

    testcase( rc!=SQLITE_OK );
  }
  if( rc==SQLITE_OK && zSuper[0] && res ){
    /* If there was a super-journal and this routine will return success,
    ** see if it is possible to delete the super-journal.
    */
    assert( zSuper==&pPager->pTmpSpace[4] );
    memset(pPager->pTmpSpace, 0, 4);
    rc = pager_delsuper(pPager, zSuper);
    testcase( rc!=SQLITE_OK );
  }
  if( isHot && nPlayback ){
    sqlite3_log(SQLITE_NOTICE_RECOVER_ROLLBACK, "recovered %d pages from %s",
                nPlayback, pPager->zJournal);
  }

  char *zPathname = 0;     /* Full path to database file */
  int nPathname = 0;       /* Number of bytes in zPathname */
  int useJournal = (flags & PAGER_OMIT_JOURNAL)==0; /* False to omit journal */
  int pcacheSize = sqlite3PcacheSize();       /* Bytes to allocate for PCache */
  u32 szPageDflt = SQLITE_DEFAULT_PAGE_SIZE;  /* Default page size */
  const char *zUri = 0;    /* URI args to copy */
  int nUriByte = 1;        /* Number of bytes of URI args at *zUri */


  /* Figure out how much space is required for each journal file-handle
  ** (there are two of them, the main journal and the sub-journal).  */
  journalFileSize = ROUND8(sqlite3JournalSize(pVfs));

  /* Set the output variable to NULL in case an error occurs. */
  *ppPager = 0;

      }
    }
    nPathname = sqlite3Strlen30(zPathname);
    z = zUri = &zFilename[sqlite3Strlen30(zFilename)+1];
    while( *z ){
      z += strlen(z)+1;
      z += strlen(z)+1;

    }
    nUriByte = (int)(&z[1] - zUri);
    assert( nUriByte>=1 );
    if( rc==SQLITE_OK && nPathname+8>pVfs->mxPathname ){
      /* This branch is taken when the journal path required by
      ** the database being opened will be more than pVfs->mxPathname
      ** bytes in length. This means the database cannot be opened,

        sqlite3MemJournalOpen(pPager->jfd);
      }else{
        int flags = SQLITE_OPEN_READWRITE|SQLITE_OPEN_CREATE;
        int nSpill;

        if( pPager->tempFile ){
          flags |= (SQLITE_OPEN_DELETEONCLOSE|SQLITE_OPEN_TEMP_JOURNAL);
          flags |= SQLITE_OPEN_EXCLUSIVE;
          nSpill = sqlite3Config.nStmtSpill;
        }else{
          flags |= SQLITE_OPEN_MAIN_JOURNAL;
          nSpill = jrnlBufferSize(pPager);
        }

        /* Verify that the database still has the same name as it did when

      rc = writeJournalHdr(pPager);
    }
  }

  if( rc!=SQLITE_OK ){
    sqlite3BitvecDestroy(pPager->pInJournal);
    pPager->pInJournal = 0;
    pPager->journalOff = 0;
  }else{
    assert( pPager->eState==PAGER_WRITER_LOCKED );
    pPager->eState = PAGER_WRITER_CACHEMOD;
  }

  return rc;
}

# define DIRECT_MODE 0
  assert( isDirectMode==0 );
  UNUSED_PARAMETER(isDirectMode);
#else
# define DIRECT_MODE isDirectMode
#endif

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

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

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

** participate in shared-cache.
**
** The return value to this routine is always safe to use with
** sqlite3_uri_parameter() and sqlite3_filename_database() and friends.
*/
SQLITE_PRIVATE const char *sqlite3PagerFilename(const Pager *pPager, int nullIfMemDb){
  static const char zFake[8] = { 0, 0, 0, 0, 0, 0, 0, 0 };
  if( nullIfMemDb && (pPager->memDb || sqlite3IsMemdb(pPager->pVfs)) ){
    return &zFake[4];
  }else{
    return pPager->zFilename;
  }
}

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

** The ISAUTOVACUUM macro is used within balance_nonroot() to determine
** if the database supports auto-vacuum or not. Because it is used
** within an expression that is an argument to another macro
** (sqliteMallocRaw), it is not possible to use conditional compilation.
** So, this macro is defined instead.
*/
#ifndef SQLITE_OMIT_AUTOVACUUM
#define ISAUTOVACUUM(pBt) (pBt->autoVacuum)
#else
#define ISAUTOVACUUM(pBt) 0
#endif


/*
** This structure is passed around through all the PRAGMA integrity_check
** checking routines in order to keep track of some global state information.
**
** The aRef[] array is allocated so that there is 1 bit for each page in
** the database. As the integrity-check proceeds, for each page used in
** the database the corresponding bit is set. This allows integrity-check to
** detect pages that are used twice and orphaned pages (both of which
** indicate corruption).
*/
typedef struct IntegrityCk IntegrityCk;
struct IntegrityCk {
  BtShared *pBt;    /* The tree being checked out */
  Pager *pPager;    /* The associated pager.  Also accessible by pBt->pPager */
  u8 *aPgRef;       /* 1 bit per page in the db (see above) */
  Pgno nPage;       /* Number of pages in the database */
  int mxErr;        /* Stop accumulating errors when this reaches zero */
  int nErr;         /* Number of messages written to zErrMsg so far */
  int rc;           /* SQLITE_OK, SQLITE_NOMEM, or SQLITE_INTERRUPT */
  u32 nStep;        /* Number of steps into the integrity_check process */
  const char *zPfx; /* Error message prefix */
  Pgno v1;          /* Value for first %u substitution in zPfx */
  int v2;           /* Value for second %d substitution in zPfx */
  StrAccum errMsg;  /* Accumulate the error message text here */
  u32 *heap;        /* Min-heap used for analyzing cell coverage */
  sqlite3 *db;      /* Database connection running the check */
};

**
** If pSchema is not NULL, then iDb is computed from pSchema and
** db using sqlite3SchemaToIndex().
*/
SQLITE_PRIVATE int sqlite3SchemaMutexHeld(sqlite3 *db, int iDb, Schema *pSchema){
  Btree *p;
  assert( db!=0 );
  if( db->pVfs==0 && db->nDb==0 ) return 1;
  if( pSchema ) iDb = sqlite3SchemaToIndex(db, pSchema);
  assert( iDb>=0 && iDb<db->nDb );
  if( !sqlite3_mutex_held(db->mutex) ) return 0;
  if( iDb==1 ) return 1;
  p = db->aDb[iDb].pBt;
  assert( p!=0 );
  return p->sharable==0 || p->locked==1;

  int iCellStart;            /* First cell offset in input */

  assert( sqlite3PagerIswriteable(pPage->pDbPage) );
  assert( pPage->pBt!=0 );
  assert( pPage->pBt->usableSize <= SQLITE_MAX_PAGE_SIZE );
  assert( pPage->nOverflow==0 );
  assert( sqlite3_mutex_held(pPage->pBt->mutex) );

  data = pPage->aData;
  hdr = pPage->hdrOffset;
  cellOffset = pPage->cellOffset;
  nCell = pPage->nCell;
  assert( nCell==get2byte(&data[hdr+3]) || CORRUPT_DB );
  iCellFirst = cellOffset + 2*nCell;
  usableSize = pPage->pBt->usableSize;

        }
        if( iFree2 ){
          if( iFree+sz>iFree2 ) return SQLITE_CORRUPT_PAGE(pPage);
          sz2 = get2byte(&data[iFree2+2]);
          if( iFree2+sz2 > usableSize ) return SQLITE_CORRUPT_PAGE(pPage);
          memmove(&data[iFree+sz+sz2], &data[iFree+sz], iFree2-(iFree+sz));
          sz += sz2;
        }else if( iFree+sz>usableSize ){
          return SQLITE_CORRUPT_PAGE(pPage);
        }

        cbrk = top+sz;
        assert( cbrk+(iFree-top) <= usableSize );
        memmove(&data[cbrk], &data[top], iFree-top);
        for(pAddr=&data[cellOffset]; pAddr<pEnd; pAddr+=2){
          pc = get2byte(pAddr);
          if( pc<iFree ){ put2byte(pAddr, pc+sz); }
          else if( pc<iFree2 ){ put2byte(pAddr, pc+sz2); }
        }
        goto defragment_out;
      }
    }
  }

  cbrk = usableSize;
  iCellLast = usableSize - 4;
  iCellStart = get2byte(&data[hdr+5]);
  if( nCell>0 ){
    temp = sqlite3PagerTempSpace(pPage->pBt->pPager);
    memcpy(&temp[iCellStart], &data[iCellStart], usableSize - iCellStart);
    src = temp;
    for(i=0; i<nCell; i++){
      u8 *pAddr;     /* The i-th cell pointer */
      pAddr = &data[cellOffset + i*2];
      pc = get2byte(pAddr);
      testcase( pc==iCellFirst );
      testcase( pc==iCellLast );
      /* These conditions have already been verified in btreeInitPage()
      ** if PRAGMA cell_size_check=ON.
      */
      if( pc<iCellStart || pc>iCellLast ){
        return SQLITE_CORRUPT_PAGE(pPage);
      }
      assert( pc>=iCellStart && pc<=iCellLast );
      size = pPage->xCellSize(pPage, &src[pc]);
      cbrk -= size;
      if( cbrk<iCellStart || pc+size>usableSize ){
        return SQLITE_CORRUPT_PAGE(pPage);
      }
      assert( cbrk+size<=usableSize && cbrk>=iCellStart );
      testcase( cbrk+size==usableSize );
      testcase( pc+size==usableSize );
      put2byte(pAddr, cbrk);



      memcpy(&data[cbrk], &src[pc], size);

    }

  }
  data[hdr+7] = 0;

defragment_out:
  assert( pPage->nFree>=0 );
  if( data[hdr+7]+cbrk-iCellFirst!=pPage->nFree ){
    return SQLITE_CORRUPT_PAGE(pPage);
  }
  assert( cbrk>=iCellFirst );
  put2byte(&data[hdr+5], cbrk);
  data[hdr+1] = 0;

        ** number of bytes in fragments may not exceed 60. */
        if( aData[hdr+7]>57 ) return 0;

        /* Remove the slot from the free-list. Update the number of
        ** fragmented bytes within the page. */
        memcpy(&aData[iAddr], &aData[pc], 2);
        aData[hdr+7] += (u8)x;

        return &aData[pc];
      }else if( x+pc > maxPC ){
        /* This slot extends off the end of the usable part of the page */
        *pRc = SQLITE_CORRUPT_PAGE(pPg);
        return 0;
      }else{
        /* The slot remains on the free-list. Reduce its size to account
        ** for the portion used by the new allocation. */
        put2byte(&aData[pc+2], x);
      }
      return &aData[pc + x];
    }
    iAddr = pc;
    pTmp = &aData[pc];
    pc = get2byte(pTmp);
    if( pc<=iAddr ){
      if( pc ){
        /* The next slot in the chain comes before the current slot */
        *pRc = SQLITE_CORRUPT_PAGE(pPg);
      }
      return 0;
    }
  }
  if( pc>maxPC+nByte-4 ){
    /* The free slot chain extends off the end of the page */

  */
  hdr = pPage->hdrOffset;
  iPtr = hdr + 1;
  if( data[iPtr+1]==0 && data[iPtr]==0 ){
    iFreeBlk = 0;  /* Shortcut for the case when the freelist is empty */
  }else{
    while( (iFreeBlk = get2byte(&data[iPtr]))<iStart ){
      if( iFreeBlk<=iPtr ){
        if( iFreeBlk==0 ) break; /* TH3: corrupt082.100 */
        return SQLITE_CORRUPT_PAGE(pPage);
      }
      iPtr = iFreeBlk;
    }
    if( iFreeBlk>pPage->pBt->usableSize-4 ){ /* TH3: corrupt081.100 */
      return SQLITE_CORRUPT_PAGE(pPage);

/*
** Decode the flags byte (the first byte of the header) for a page
** and initialize fields of the MemPage structure accordingly.
**
** Only the following combinations are supported.  Anything different
** indicates a corrupt database files:
**
**         PTF_ZERODATA                             (0x02,  2)
**         PTF_LEAFDATA | PTF_INTKEY                (0x05,  5)
**         PTF_ZERODATA | PTF_LEAF                  (0x0a, 10)
**         PTF_LEAFDATA | PTF_INTKEY | PTF_LEAF     (0x0d, 13)

*/
static int decodeFlags(MemPage *pPage, int flagByte){
  BtShared *pBt;     /* A copy of pPage->pBt */

  assert( pPage->hdrOffset==(pPage->pgno==1 ? 100 : 0) );
  assert( sqlite3_mutex_held(pPage->pBt->mutex) );
  pBt = pPage->pBt;
  pPage->max1bytePayload = pBt->max1bytePayload;
  if( flagByte>=(PTF_ZERODATA | PTF_LEAF) ){
    pPage->childPtrSize = 0;
    pPage->leaf = 1;
    if( flagByte==(PTF_LEAFDATA | PTF_INTKEY | PTF_LEAF) ){

      pPage->intKeyLeaf = 1;
      pPage->xCellSize = cellSizePtrTableLeaf;
      pPage->xParseCell = btreeParseCellPtr;
      pPage->intKey = 1;
      pPage->maxLocal = pBt->maxLeaf;
      pPage->minLocal = pBt->minLeaf;
    }else if( flagByte==(PTF_ZERODATA | PTF_LEAF) ){
      pPage->intKey = 0;
      pPage->intKeyLeaf = 0;
      pPage->xCellSize = cellSizePtr;
      pPage->xParseCell = btreeParseCellPtrIndex;
      pPage->maxLocal = pBt->maxLocal;
      pPage->minLocal = pBt->minLocal;
    }else{
      pPage->intKey = 0;
      pPage->intKeyLeaf = 0;
      pPage->xCellSize = cellSizePtr;
      pPage->xParseCell = btreeParseCellPtrIndex;
      return SQLITE_CORRUPT_PAGE(pPage);
    }
  }else{
    pPage->childPtrSize = 4;
    pPage->leaf = 0;
    if( flagByte==(PTF_ZERODATA) ){
      pPage->intKey = 0;
      pPage->intKeyLeaf = 0;
      pPage->xCellSize = cellSizePtr;
      pPage->xParseCell = btreeParseCellPtrIndex;
      pPage->maxLocal = pBt->maxLocal;
      pPage->minLocal = pBt->minLocal;
    }else if( flagByte==(PTF_LEAFDATA | PTF_INTKEY) ){
      pPage->intKeyLeaf = 0;
      pPage->xCellSize = cellSizePtrNoPayload;
      pPage->xParseCell = btreeParseCellPtrNoPayload;











      pPage->intKey = 1;


      pPage->maxLocal = pBt->maxLeaf;
      pPage->minLocal = pBt->minLeaf;
    }else{


      pPage->intKey = 0;
      pPage->intKeyLeaf = 0;
      pPage->xCellSize = cellSizePtr;
      pPage->xParseCell = btreeParseCellPtrIndex;
      return SQLITE_CORRUPT_PAGE(pPage);
    }
  }

  return SQLITE_OK;
}

/*
** Compute the amount of freespace on the page.  In other words, fill
** in the pPage->nFree field.
*/

  releasePage(*ppPage);
getAndInitPage_error1:
  if( pCur ){
    pCur->iPage--;
    pCur->pPage = pCur->apPage[pCur->iPage];
  }
  testcase( pgno==0 );
  assert( pgno!=0 || rc!=SQLITE_OK );


  return rc;
}

/*
** Release a MemPage.  This should be called once for each prior
** call to btreeGetPage.
**

          }
          if( iFrom==get4byte(pCell+info.nSize-4) ){
            put4byte(pCell+info.nSize-4, iTo);
            break;
          }
        }
      }else{
        if( pCell+4 > pPage->aData+pPage->pBt->usableSize ){
          return SQLITE_CORRUPT_PAGE(pPage);
        }
        if( get4byte(pCell)==iFrom ){
          put4byte(pCell, iTo);
          break;
        }
      }
    }

**
** This function returns SQLITE_CORRUPT if the page-header flags field of
** the new child page does not match the flags field of the parent (i.e.
** if an intkey page appears to be the parent of a non-intkey page, or
** vice-versa).
*/
static int moveToChild(BtCursor *pCur, u32 newPgno){


  assert( cursorOwnsBtShared(pCur) );
  assert( pCur->eState==CURSOR_VALID );
  assert( pCur->iPage<BTCURSOR_MAX_DEPTH );
  assert( pCur->iPage>=0 );
  if( pCur->iPage>=(BTCURSOR_MAX_DEPTH-1) ){
    return SQLITE_CORRUPT_BKPT;
  }
  pCur->info.nSize = 0;
  pCur->curFlags &= ~(BTCF_ValidNKey|BTCF_ValidOvfl);
  pCur->aiIdx[pCur->iPage] = pCur->ix;
  pCur->apPage[pCur->iPage] = pCur->pPage;
  pCur->ix = 0;
  pCur->iPage++;
  return getAndInitPage(pCur->pBt, newPgno, &pCur->pPage, pCur,
                        pCur->curPagerFlags);
}

#ifdef SQLITE_DEBUG
/*
** Page pParent is an internal (non-leaf) tree page. This function
** asserts that page number iChild is the left-child if the iIdx'th
** cell in page pParent. Or, if iIdx is equal to the total number of

    if( pCur->eState>=CURSOR_REQUIRESEEK ){
      if( pCur->eState==CURSOR_FAULT ){
        assert( pCur->skipNext!=SQLITE_OK );
        return pCur->skipNext;
      }
      sqlite3BtreeClearCursor(pCur);
    }
    rc = getAndInitPage(pCur->pBt, pCur->pgnoRoot, &pCur->pPage,
                        0, pCur->curPagerFlags);
    if( rc!=SQLITE_OK ){
      pCur->eState = CURSOR_INVALID;
      return rc;
    }
    pCur->iPage = 0;
    pCur->curIntKey = pCur->pPage->intKey;

  return rc;
}

/* Move the cursor to the last entry in the table.  Return SQLITE_OK
** on success.  Set *pRes to 0 if the cursor actually points to something
** or set *pRes to 1 if the table is empty.
*/
static SQLITE_NOINLINE int btreeLast(BtCursor *pCur, int *pRes){
  int rc = moveToRoot(pCur);
  if( rc==SQLITE_OK ){
    assert( pCur->eState==CURSOR_VALID );
    *pRes = 0;
    rc = moveToRightmost(pCur);
    if( rc==SQLITE_OK ){
      pCur->curFlags |= BTCF_AtLast;
    }else{
      pCur->curFlags &= ~BTCF_AtLast;
    }
  }else if( rc==SQLITE_EMPTY ){
    assert( pCur->pgnoRoot==0 || pCur->pPage->nCell==0 );
    *pRes = 1;
    rc = SQLITE_OK;
  }
  return rc;
}
SQLITE_PRIVATE int sqlite3BtreeLast(BtCursor *pCur, int *pRes){
  assert( cursorOwnsBtShared(pCur) );
  assert( sqlite3_mutex_held(pCur->pBtree->db->mutex) );

  /* If the cursor already points to the last entry, this is a no-op. */
  if( CURSOR_VALID==pCur->eState && (pCur->curFlags & BTCF_AtLast)!=0 ){
#ifdef SQLITE_DEBUG
    /* This block serves to assert() that the cursor really does point
    ** to the last entry in the b-tree. */
    int ii;
    for(ii=0; ii<pCur->iPage; ii++){
      assert( pCur->aiIdx[ii]==pCur->apPage[ii]->nCell );
    }
    assert( pCur->ix==pCur->pPage->nCell-1 || CORRUPT_DB );
    testcase( pCur->ix!=pCur->pPage->nCell-1 );
    /* ^-- dbsqlfuzz b92b72e4de80b5140c30ab71372ca719b8feb618 */
    assert( pCur->pPage->leaf );
#endif
    *pRes = 0;
    return SQLITE_OK;
  }
















  return btreeLast(pCur, pRes);
}

/* Move the cursor so that it points to an entry in a table (a.k.a INTKEY)
** table near the key intKey.   Return a success code.
**
** If an exact match is not found, then the cursor is always
** left pointing at a leaf page which would hold the entry if it