+/*
+** CAPI3REF: Status Parameters for prepared statements
+** KEYWORDS: {SQLITE_STMTSTATUS counter} {SQLITE_STMTSTATUS counters}
+**
+** These preprocessor macros define integer codes that name counter
+** values associated with the [sqlite3_stmt_status()] interface.
+** The meanings of the various counters are as follows:
+**
+** <dl>
+** [[SQLITE_STMTSTATUS_FULLSCAN_STEP]] <dt>SQLITE_STMTSTATUS_FULLSCAN_STEP</dt>
+** <dd>^This is the number of times that SQLite has stepped forward in
+** a table as part of a full table scan. Large numbers for this counter
+** may indicate opportunities for performance improvement through
+** careful use of indices.</dd>
+**
+** [[SQLITE_STMTSTATUS_SORT]] <dt>SQLITE_STMTSTATUS_SORT</dt>
+** <dd>^This is the number of sort operations that have occurred.
+** A non-zero value in this counter may indicate an opportunity to
+** improvement performance through careful use of indices.</dd>
+**
+** [[SQLITE_STMTSTATUS_AUTOINDEX]] <dt>SQLITE_STMTSTATUS_AUTOINDEX</dt>
+** <dd>^This is the number of rows inserted into transient indices that
+** were created automatically in order to help joins run faster.
+** A non-zero value in this counter may indicate an opportunity to
+** improvement performance by adding permanent indices that do not
+** need to be reinitialized each time the statement is run.</dd>
+**
+** [[SQLITE_STMTSTATUS_VM_STEP]] <dt>SQLITE_STMTSTATUS_VM_STEP</dt>
+** <dd>^This is the number of virtual machine operations executed
+** by the prepared statement if that number is less than or equal
+** to 2147483647. The number of virtual machine operations can be
+** used as a proxy for the total work done by the prepared statement.
+** If the number of virtual machine operations exceeds 2147483647
+** then the value returned by this statement status code is undefined.
+**
+** [[SQLITE_STMTSTATUS_REPREPARE]] <dt>SQLITE_STMTSTATUS_REPREPARE</dt>
+** <dd>^This is the number of times that the prepare statement has been
+** automatically regenerated due to schema changes or change to
+** [bound parameters] that might affect the query plan.
+**
+** [[SQLITE_STMTSTATUS_RUN]] <dt>SQLITE_STMTSTATUS_RUN</dt>
+** <dd>^This is the number of times that the prepared statement has
+** been run. A single "run" for the purposes of this counter is one
+** or more calls to [sqlite3_step()] followed by a call to [sqlite3_reset()].
+** The counter is incremented on the first [sqlite3_step()] call of each
+** cycle.
+**
+** [[SQLITE_STMTSTATUS_MEMUSED]] <dt>SQLITE_STMTSTATUS_MEMUSED</dt>
+** <dd>^This is the approximate number of bytes of heap memory
+** used to store the prepared statement. ^This value is not actually
+** a counter, and so the resetFlg parameter to sqlite3_stmt_status()
+** is ignored when the opcode is SQLITE_STMTSTATUS_MEMUSED.
+** </dd>
+** </dl>
+*/
+#define SQLITE_STMTSTATUS_FULLSCAN_STEP 1
+#define SQLITE_STMTSTATUS_SORT 2
+#define SQLITE_STMTSTATUS_AUTOINDEX 3
+#define SQLITE_STMTSTATUS_VM_STEP 4
+#define SQLITE_STMTSTATUS_REPREPARE 5
+#define SQLITE_STMTSTATUS_RUN 6
+#define SQLITE_STMTSTATUS_MEMUSED 99
+
+/*
+** CAPI3REF: Custom Page Cache Object
+**
+** The sqlite3_pcache type is opaque. It is implemented by
+** the pluggable module. The SQLite core has no knowledge of
+** its size or internal structure and never deals with the
+** sqlite3_pcache object except by holding and passing pointers
+** to the object.
+**
+** See [sqlite3_pcache_methods2] for additional information.
+*/
+typedef struct sqlite3_pcache sqlite3_pcache;
+
+/*
+** CAPI3REF: Custom Page Cache Object
+**
+** The sqlite3_pcache_page object represents a single page in the
+** page cache. The page cache will allocate instances of this
+** object. Various methods of the page cache use pointers to instances
+** of this object as parameters or as their return value.
+**
+** See [sqlite3_pcache_methods2] for additional information.
+*/
+typedef struct sqlite3_pcache_page sqlite3_pcache_page;
+struct sqlite3_pcache_page {
+ void *pBuf; /* The content of the page */
+ void *pExtra; /* Extra information associated with the page */
+};
+
+/*
+** CAPI3REF: Application Defined Page Cache.
+** KEYWORDS: {page cache}
+**
+** ^(The [sqlite3_config]([SQLITE_CONFIG_PCACHE2], ...) interface can
+** register an alternative page cache implementation by passing in an
+** instance of the sqlite3_pcache_methods2 structure.)^
+** In many applications, most of the heap memory allocated by
+** SQLite is used for the page cache.
+** By implementing a
+** custom page cache using this API, an application can better control
+** the amount of memory consumed by SQLite, the way in which
+** that memory is allocated and released, and the policies used to
+** determine exactly which parts of a database file are cached and for
+** how long.
+**
+** The alternative page cache mechanism is an
+** extreme measure that is only needed by the most demanding applications.
+** The built-in page cache is recommended for most uses.
+**
+** ^(The contents of the sqlite3_pcache_methods2 structure are copied to an
+** internal buffer by SQLite within the call to [sqlite3_config]. Hence
+** the application may discard the parameter after the call to
+** [sqlite3_config()] returns.)^
+**
+** [[the xInit() page cache method]]
+** ^(The xInit() method is called once for each effective
+** call to [sqlite3_initialize()])^
+** (usually only once during the lifetime of the process). ^(The xInit()
+** method is passed a copy of the sqlite3_pcache_methods2.pArg value.)^
+** The intent of the xInit() method is to set up global data structures
+** required by the custom page cache implementation.
+** ^(If the xInit() method is NULL, then the
+** built-in default page cache is used instead of the application defined
+** page cache.)^
+**
+** [[the xShutdown() page cache method]]
+** ^The xShutdown() method is called by [sqlite3_shutdown()].
+** It can be used to clean up
+** any outstanding resources before process shutdown, if required.
+** ^The xShutdown() method may be NULL.
+**
+** ^SQLite automatically serializes calls to the xInit method,
+** so the xInit method need not be threadsafe. ^The
+** xShutdown method is only called from [sqlite3_shutdown()] so it does
+** not need to be threadsafe either. All other methods must be threadsafe
+** in multithreaded applications.
+**
+** ^SQLite will never invoke xInit() more than once without an intervening
+** call to xShutdown().
+**
+** [[the xCreate() page cache methods]]
+** ^SQLite invokes the xCreate() method to construct a new cache instance.
+** SQLite will typically create one cache instance for each open database file,
+** though this is not guaranteed. ^The
+** first parameter, szPage, is the size in bytes of the pages that must
+** be allocated by the cache. ^szPage will always a power of two. ^The
+** second parameter szExtra is a number of bytes of extra storage
+** associated with each page cache entry. ^The szExtra parameter will
+** a number less than 250. SQLite will use the
+** extra szExtra bytes on each page to store metadata about the underlying
+** database page on disk. The value passed into szExtra depends
+** on the SQLite version, the target platform, and how SQLite was compiled.
+** ^The third argument to xCreate(), bPurgeable, is true if the cache being
+** created will be used to cache database pages of a file stored on disk, or
+** false if it is used for an in-memory database. The cache implementation
+** does not have to do anything special based with the value of bPurgeable;
+** it is purely advisory. ^On a cache where bPurgeable is false, SQLite will
+** never invoke xUnpin() except to deliberately delete a page.
+** ^In other words, calls to xUnpin() on a cache with bPurgeable set to
+** false will always have the "discard" flag set to true.
+** ^Hence, a cache created with bPurgeable false will
+** never contain any unpinned pages.
+**
+** [[the xCachesize() page cache method]]
+** ^(The xCachesize() method may be called at any time by SQLite to set the
+** suggested maximum cache-size (number of pages stored by) the cache
+** instance passed as the first argument. This is the value configured using
+** the SQLite "[PRAGMA cache_size]" command.)^ As with the bPurgeable
+** parameter, the implementation is not required to do anything with this
+** value; it is advisory only.
+**
+** [[the xPagecount() page cache methods]]
+** The xPagecount() method must return the number of pages currently
+** stored in the cache, both pinned and unpinned.
+**
+** [[the xFetch() page cache methods]]
+** The xFetch() method locates a page in the cache and returns a pointer to
+** an sqlite3_pcache_page object associated with that page, or a NULL pointer.
+** The pBuf element of the returned sqlite3_pcache_page object will be a
+** pointer to a buffer of szPage bytes used to store the content of a
+** single database page. The pExtra element of sqlite3_pcache_page will be
+** a pointer to the szExtra bytes of extra storage that SQLite has requested
+** for each entry in the page cache.
+**
+** The page to be fetched is determined by the key. ^The minimum key value
+** is 1. After it has been retrieved using xFetch, the page is considered
+** to be "pinned".
+**
+** If the requested page is already in the page cache, then the page cache
+** implementation must return a pointer to the page buffer with its content
+** intact. If the requested page is not already in the cache, then the
+** cache implementation should use the value of the createFlag
+** parameter to help it determined what action to take:
+**
+** <table border=1 width=85% align=center>
+** <tr><th> createFlag <th> Behavior when page is not already in cache
+** <tr><td> 0 <td> Do not allocate a new page. Return NULL.
+** <tr><td> 1 <td> Allocate a new page if it easy and convenient to do so.
+** Otherwise return NULL.
+** <tr><td> 2 <td> Make every effort to allocate a new page. Only return
+** NULL if allocating a new page is effectively impossible.
+** </table>
+**
+** ^(SQLite will normally invoke xFetch() with a createFlag of 0 or 1. SQLite
+** will only use a createFlag of 2 after a prior call with a createFlag of 1
+** failed.)^ In between the to xFetch() calls, SQLite may
+** attempt to unpin one or more cache pages by spilling the content of
+** pinned pages to disk and synching the operating system disk cache.
+**
+** [[the xUnpin() page cache method]]
+** ^xUnpin() is called by SQLite with a pointer to a currently pinned page
+** as its second argument. If the third parameter, discard, is non-zero,
+** then the page must be evicted from the cache.
+** ^If the discard parameter is
+** zero, then the page may be discarded or retained at the discretion of
+** page cache implementation. ^The page cache implementation
+** may choose to evict unpinned pages at any time.
+**
+** The cache must not perform any reference counting. A single
+** call to xUnpin() unpins the page regardless of the number of prior calls
+** to xFetch().
+**
+** [[the xRekey() page cache methods]]
+** The xRekey() method is used to change the key value associated with the
+** page passed as the second argument. If the cache
+** previously contains an entry associated with newKey, it must be
+** discarded. ^Any prior cache entry associated with newKey is guaranteed not
+** to be pinned.
+**
+** When SQLite calls the xTruncate() method, the cache must discard all
+** existing cache entries with page numbers (keys) greater than or equal
+** to the value of the iLimit parameter passed to xTruncate(). If any
+** of these pages are pinned, they are implicitly unpinned, meaning that
+** they can be safely discarded.
+**
+** [[the xDestroy() page cache method]]
+** ^The xDestroy() method is used to delete a cache allocated by xCreate().
+** All resources associated with the specified cache should be freed. ^After
+** calling the xDestroy() method, SQLite considers the [sqlite3_pcache*]
+** handle invalid, and will not use it with any other sqlite3_pcache_methods2
+** functions.
+**
+** [[the xShrink() page cache method]]
+** ^SQLite invokes the xShrink() method when it wants the page cache to
+** free up as much of heap memory as possible. The page cache implementation
+** is not obligated to free any memory, but well-behaved implementations should
+** do their best.
+*/
+typedef struct sqlite3_pcache_methods2 sqlite3_pcache_methods2;
+struct sqlite3_pcache_methods2 {
+ int iVersion;
+ void *pArg;
+ int (*xInit)(void*);
+ void (*xShutdown)(void*);
+ sqlite3_pcache *(*xCreate)(int szPage, int szExtra, int bPurgeable);
+ void (*xCachesize)(sqlite3_pcache*, int nCachesize);
+ int (*xPagecount)(sqlite3_pcache*);
+ sqlite3_pcache_page *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag);
+ void (*xUnpin)(sqlite3_pcache*, sqlite3_pcache_page*, int discard);
+ void (*xRekey)(sqlite3_pcache*, sqlite3_pcache_page*,
+ unsigned oldKey, unsigned newKey);
+ void (*xTruncate)(sqlite3_pcache*, unsigned iLimit);
+ void (*xDestroy)(sqlite3_pcache*);
+ void (*xShrink)(sqlite3_pcache*);
+};
+
+/*
+** This is the obsolete pcache_methods object that has now been replaced
+** by sqlite3_pcache_methods2. This object is not used by SQLite. It is
+** retained in the header file for backwards compatibility only.
+*/
+typedef struct sqlite3_pcache_methods sqlite3_pcache_methods;
+struct sqlite3_pcache_methods {
+ void *pArg;
+ int (*xInit)(void*);
+ void (*xShutdown)(void*);
+ sqlite3_pcache *(*xCreate)(int szPage, int bPurgeable);
+ void (*xCachesize)(sqlite3_pcache*, int nCachesize);
+ int (*xPagecount)(sqlite3_pcache*);
+ void *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag);
+ void (*xUnpin)(sqlite3_pcache*, void*, int discard);
+ void (*xRekey)(sqlite3_pcache*, void*, unsigned oldKey, unsigned newKey);
+ void (*xTruncate)(sqlite3_pcache*, unsigned iLimit);
+ void (*xDestroy)(sqlite3_pcache*);
+};
+
+
+/*
+** CAPI3REF: Online Backup Object
+**
+** The sqlite3_backup object records state information about an ongoing
+** online backup operation. ^The sqlite3_backup object is created by
+** a call to [sqlite3_backup_init()] and is destroyed by a call to
+** [sqlite3_backup_finish()].
+**
+** See Also: [Using the SQLite Online Backup API]
+*/
+typedef struct sqlite3_backup sqlite3_backup;
+
+/*
+** CAPI3REF: Online Backup API.
+**
+** The backup API copies the content of one database into another.
+** It is useful either for creating backups of databases or
+** for copying in-memory databases to or from persistent files.
+**
+** See Also: [Using the SQLite Online Backup API]
+**
+** ^SQLite holds a write transaction open on the destination database file
+** for the duration of the backup operation.
+** ^The source database is read-locked only while it is being read;
+** it is not locked continuously for the entire backup operation.
+** ^Thus, the backup may be performed on a live source database without
+** preventing other database connections from
+** reading or writing to the source database while the backup is underway.
+**
+** ^(To perform a backup operation:
+** <ol>
+** <li><b>sqlite3_backup_init()</b> is called once to initialize the
+** backup,
+** <li><b>sqlite3_backup_step()</b> is called one or more times to transfer
+** the data between the two databases, and finally
+** <li><b>sqlite3_backup_finish()</b> is called to release all resources
+** associated with the backup operation.
+** </ol>)^
+** There should be exactly one call to sqlite3_backup_finish() for each
+** successful call to sqlite3_backup_init().
+**
+** [[sqlite3_backup_init()]] <b>sqlite3_backup_init()</b>
+**
+** ^The D and N arguments to sqlite3_backup_init(D,N,S,M) are the
+** [database connection] associated with the destination database
+** and the database name, respectively.
+** ^The database name is "main" for the main database, "temp" for the
+** temporary database, or the name specified after the AS keyword in
+** an [ATTACH] statement for an attached database.
+** ^The S and M arguments passed to
+** sqlite3_backup_init(D,N,S,M) identify the [database connection]
+** and database name of the source database, respectively.
+** ^The source and destination [database connections] (parameters S and D)
+** must be different or else sqlite3_backup_init(D,N,S,M) will fail with
+** an error.
+**
+** ^A call to sqlite3_backup_init() will fail, returning NULL, if
+** there is already a read or read-write transaction open on the
+** destination database.
+**
+** ^If an error occurs within sqlite3_backup_init(D,N,S,M), then NULL is
+** returned and an error code and error message are stored in the
+** destination [database connection] D.
+** ^The error code and message for the failed call to sqlite3_backup_init()
+** can be retrieved using the [sqlite3_errcode()], [sqlite3_errmsg()], and/or
+** [sqlite3_errmsg16()] functions.
+** ^A successful call to sqlite3_backup_init() returns a pointer to an
+** [sqlite3_backup] object.
+** ^The [sqlite3_backup] object may be used with the sqlite3_backup_step() and
+** sqlite3_backup_finish() functions to perform the specified backup
+** operation.
+**
+** [[sqlite3_backup_step()]] <b>sqlite3_backup_step()</b>
+**
+** ^Function sqlite3_backup_step(B,N) will copy up to N pages between
+** the source and destination databases specified by [sqlite3_backup] object B.
+** ^If N is negative, all remaining source pages are copied.
+** ^If sqlite3_backup_step(B,N) successfully copies N pages and there
+** are still more pages to be copied, then the function returns [SQLITE_OK].
+** ^If sqlite3_backup_step(B,N) successfully finishes copying all pages
+** from source to destination, then it returns [SQLITE_DONE].
+** ^If an error occurs while running sqlite3_backup_step(B,N),
+** then an [error code] is returned. ^As well as [SQLITE_OK] and
+** [SQLITE_DONE], a call to sqlite3_backup_step() may return [SQLITE_READONLY],
+** [SQLITE_NOMEM], [SQLITE_BUSY], [SQLITE_LOCKED], or an
+** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX] extended error code.
+**
+** ^(The sqlite3_backup_step() might return [SQLITE_READONLY] if
+** <ol>
+** <li> the destination database was opened read-only, or
+** <li> the destination database is using write-ahead-log journaling
+** and the destination and source page sizes differ, or
+** <li> the destination database is an in-memory database and the
+** destination and source page sizes differ.
+** </ol>)^
+**
+** ^If sqlite3_backup_step() cannot obtain a required file-system lock, then
+** the [sqlite3_busy_handler | busy-handler function]
+** is invoked (if one is specified). ^If the
+** busy-handler returns non-zero before the lock is available, then
+** [SQLITE_BUSY] is returned to the caller. ^In this case the call to
+** sqlite3_backup_step() can be retried later. ^If the source
+** [database connection]
+** is being used to write to the source database when sqlite3_backup_step()
+** is called, then [SQLITE_LOCKED] is returned immediately. ^Again, in this
+** case the call to sqlite3_backup_step() can be retried later on. ^(If
+** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX], [SQLITE_NOMEM], or
+** [SQLITE_READONLY] is returned, then
+** there is no point in retrying the call to sqlite3_backup_step(). These
+** errors are considered fatal.)^ The application must accept
+** that the backup operation has failed and pass the backup operation handle
+** to the sqlite3_backup_finish() to release associated resources.
+**
+** ^The first call to sqlite3_backup_step() obtains an exclusive lock
+** on the destination file. ^The exclusive lock is not released until either
+** sqlite3_backup_finish() is called or the backup operation is complete
+** and sqlite3_backup_step() returns [SQLITE_DONE]. ^Every call to
+** sqlite3_backup_step() obtains a [shared lock] on the source database that
+** lasts for the duration of the sqlite3_backup_step() call.
+** ^Because the source database is not locked between calls to
+** sqlite3_backup_step(), the source database may be modified mid-way
+** through the backup process. ^If the source database is modified by an
+** external process or via a database connection other than the one being
+** used by the backup operation, then the backup will be automatically
+** restarted by the next call to sqlite3_backup_step(). ^If the source
+** database is modified by the using the same database connection as is used
+** by the backup operation, then the backup database is automatically
+** updated at the same time.
+**
+** [[sqlite3_backup_finish()]] <b>sqlite3_backup_finish()</b>
+**
+** When sqlite3_backup_step() has returned [SQLITE_DONE], or when the
+** application wishes to abandon the backup operation, the application
+** should destroy the [sqlite3_backup] by passing it to sqlite3_backup_finish().
+** ^The sqlite3_backup_finish() interfaces releases all
+** resources associated with the [sqlite3_backup] object.
+** ^If sqlite3_backup_step() has not yet returned [SQLITE_DONE], then any
+** active write-transaction on the destination database is rolled back.
+** The [sqlite3_backup] object is invalid
+** and may not be used following a call to sqlite3_backup_finish().
+**
+** ^The value returned by sqlite3_backup_finish is [SQLITE_OK] if no
+** sqlite3_backup_step() errors occurred, regardless or whether or not
+** sqlite3_backup_step() completed.
+** ^If an out-of-memory condition or IO error occurred during any prior
+** sqlite3_backup_step() call on the same [sqlite3_backup] object, then
+** sqlite3_backup_finish() returns the corresponding [error code].
+**
+** ^A return of [SQLITE_BUSY] or [SQLITE_LOCKED] from sqlite3_backup_step()
+** is not a permanent error and does not affect the return value of
+** sqlite3_backup_finish().
+**
+** [[sqlite3_backup_remaining()]] [[sqlite3_backup_pagecount()]]
+** <b>sqlite3_backup_remaining() and sqlite3_backup_pagecount()</b>
+**
+** ^The sqlite3_backup_remaining() routine returns the number of pages still
+** to be backed up at the conclusion of the most recent sqlite3_backup_step().
+** ^The sqlite3_backup_pagecount() routine returns the total number of pages
+** in the source database at the conclusion of the most recent
+** sqlite3_backup_step().
+** ^(The values returned by these functions are only updated by
+** sqlite3_backup_step(). If the source database is modified in a way that
+** changes the size of the source database or the number of pages remaining,
+** those changes are not reflected in the output of sqlite3_backup_pagecount()
+** and sqlite3_backup_remaining() until after the next
+** sqlite3_backup_step().)^
+**
+** <b>Concurrent Usage of Database Handles</b>
+**
+** ^The source [database connection] may be used by the application for other
+** purposes while a backup operation is underway or being initialized.
+** ^If SQLite is compiled and configured to support threadsafe database
+** connections, then the source database connection may be used concurrently
+** from within other threads.
+**
+** 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 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().
+**
+** The [sqlite3_backup] object itself is partially threadsafe. Multiple
+** threads may safely make multiple concurrent calls to sqlite3_backup_step().
+** However, the sqlite3_backup_remaining() and sqlite3_backup_pagecount()
+** APIs are not strictly speaking threadsafe. If they are invoked at the
+** same time as another thread is invoking sqlite3_backup_step() it is
+** possible that they return invalid values.
+*/
+SQLITE_API sqlite3_backup *sqlite3_backup_init(
+ sqlite3 *pDest, /* Destination database handle */
+ const char *zDestName, /* Destination database name */
+ sqlite3 *pSource, /* Source database handle */
+ const char *zSourceName /* Source database name */
+);
+SQLITE_API int sqlite3_backup_step(sqlite3_backup *p, int nPage);
+SQLITE_API int sqlite3_backup_finish(sqlite3_backup *p);
+SQLITE_API int sqlite3_backup_remaining(sqlite3_backup *p);
+SQLITE_API int sqlite3_backup_pagecount(sqlite3_backup *p);
+
+/*
+** CAPI3REF: Unlock Notification
+** METHOD: sqlite3
+**
+** ^When running in shared-cache mode, a database operation may fail with
+** an [SQLITE_LOCKED] error if the required locks on the shared-cache or
+** individual tables within the shared-cache cannot be obtained. See
+** [SQLite Shared-Cache Mode] for a description of shared-cache locking.
+** ^This API may be used to register a callback that SQLite will invoke
+** when the connection currently holding the required lock relinquishes it.
+** ^This API is only available if the library was compiled with the
+** [SQLITE_ENABLE_UNLOCK_NOTIFY] C-preprocessor symbol defined.
+**
+** See Also: [Using the SQLite Unlock Notification Feature].
+**
+** ^Shared-cache locks are released when a database connection concludes
+** its current transaction, either by committing it or rolling it back.
+**
+** ^When a connection (known as the blocked connection) fails to obtain a
+** shared-cache lock and SQLITE_LOCKED is returned to the caller, the
+** identity of the database connection (the blocking connection) that
+** has locked the required resource is stored internally. ^After an
+** application receives an SQLITE_LOCKED error, it may call the
+** sqlite3_unlock_notify() method with the blocked connection handle as
+** the first argument to register for a callback that will be invoked
+** when the blocking connections current transaction is concluded. ^The
+** callback is invoked from within the [sqlite3_step] or [sqlite3_close]
+** call that concludes the blocking connections transaction.
+**
+** ^(If sqlite3_unlock_notify() is called in a multi-threaded application,
+** there is a chance that the blocking connection will have already
+** concluded its transaction by the time sqlite3_unlock_notify() is invoked.
+** If this happens, then the specified callback is invoked immediately,
+** from within the call to sqlite3_unlock_notify().)^
+**
+** ^If the blocked connection is attempting to obtain a write-lock on a
+** shared-cache table, and more than one other connection currently holds
+** a read-lock on the same table, then SQLite arbitrarily selects one of
+** the other connections to use as the blocking connection.
+**
+** ^(There may be at most one unlock-notify callback registered by a
+** blocked connection. If sqlite3_unlock_notify() is called when the
+** blocked connection already has a registered unlock-notify callback,
+** then the new callback replaces the old.)^ ^If sqlite3_unlock_notify() is
+** called with a NULL pointer as its second argument, then any existing
+** unlock-notify callback is canceled. ^The blocked connections
+** unlock-notify callback may also be canceled by closing the blocked
+** connection using [sqlite3_close()].
+**
+** The unlock-notify callback is not reentrant. If an application invokes
+** any sqlite3_xxx API functions from within an unlock-notify callback, a
+** crash or deadlock may be the result.
+**
+** ^Unless deadlock is detected (see below), sqlite3_unlock_notify() always
+** returns SQLITE_OK.
+**
+** <b>Callback Invocation Details</b>
+**
+** When an unlock-notify callback is registered, the application provides a
+** single void* pointer that is passed to the callback when it is invoked.
+** However, the signature of the callback function allows SQLite to pass
+** it an array of void* context pointers. The first argument passed to
+** an unlock-notify callback is a pointer to an array of void* pointers,
+** and the second is the number of entries in the array.
+**
+** When a blocking connections transaction is concluded, there may be
+** more than one blocked connection that has registered for an unlock-notify
+** callback. ^If two or more such blocked connections have specified the
+** same callback function, then instead of invoking the callback function
+** multiple times, it is invoked once with the set of void* context pointers
+** specified by the blocked connections bundled together into an array.
+** This gives the application an opportunity to prioritize any actions
+** related to the set of unblocked database connections.
+**
+** <b>Deadlock Detection</b>
+**
+** Assuming that after registering for an unlock-notify callback a
+** database waits for the callback to be issued before taking any further
+** action (a reasonable assumption), then using this API may cause the
+** application to deadlock. For example, if connection X is waiting for
+** connection Y's transaction to be concluded, and similarly connection
+** Y is waiting on connection X's transaction, then neither connection
+** will proceed and the system may remain deadlocked indefinitely.
+**
+** To avoid this scenario, the sqlite3_unlock_notify() performs deadlock
+** detection. ^If a given call to sqlite3_unlock_notify() would put the
+** system in a deadlocked state, then SQLITE_LOCKED is returned and no
+** unlock-notify callback is registered. The system is said to be in
+** a deadlocked state if connection A has registered for an unlock-notify
+** callback on the conclusion of connection B's transaction, and connection
+** B has itself registered for an unlock-notify callback when connection
+** A's transaction is concluded. ^Indirect deadlock is also detected, so
+** the system is also considered to be deadlocked if connection B has
+** registered for an unlock-notify callback on the conclusion of connection
+** C's transaction, where connection C is waiting on connection A. ^Any
+** number of levels of indirection are allowed.
+**
+** <b>The "DROP TABLE" Exception</b>
+**
+** When a call to [sqlite3_step()] returns SQLITE_LOCKED, it is almost
+** always appropriate to call sqlite3_unlock_notify(). There is however,
+** one exception. When executing a "DROP TABLE" or "DROP INDEX" statement,
+** SQLite checks if there are any currently executing SELECT statements
+** that belong to the same connection. If there are, SQLITE_LOCKED is
+** returned. In this case there is no "blocking connection", so invoking
+** sqlite3_unlock_notify() results in the unlock-notify callback being
+** invoked immediately. If the application then re-attempts the "DROP TABLE"
+** or "DROP INDEX" query, an infinite loop might be the result.
+**
+** One way around this problem is to check the extended error code returned
+** by an sqlite3_step() call. ^(If there is a blocking connection, then the
+** extended error code is set to SQLITE_LOCKED_SHAREDCACHE. Otherwise, in
+** the special "DROP TABLE/INDEX" case, the extended error code is just
+** SQLITE_LOCKED.)^
+*/
+SQLITE_API int sqlite3_unlock_notify(
+ sqlite3 *pBlocked, /* Waiting connection */
+ void (*xNotify)(void **apArg, int nArg), /* Callback function to invoke */
+ void *pNotifyArg /* Argument to pass to xNotify */
+);
+
+
+/*
+** CAPI3REF: String Comparison
+**
+** ^The [sqlite3_stricmp()] and [sqlite3_strnicmp()] APIs allow applications
+** and extensions to compare the contents of two buffers containing UTF-8
+** strings in a case-independent fashion, using the same definition of "case
+** independence" that SQLite uses internally when comparing identifiers.
+*/
+SQLITE_API int sqlite3_stricmp(const char *, const char *);
+SQLITE_API int sqlite3_strnicmp(const char *, const char *, int);
+
+/*
+** CAPI3REF: String Globbing
+*
+** ^The [sqlite3_strglob(P,X)] interface returns zero if and only if
+** string X matches the [GLOB] pattern P.
+** ^The definition of [GLOB] pattern matching used in
+** [sqlite3_strglob(P,X)] is the same as for the "X GLOB P" operator in the
+** SQL dialect understood by SQLite. ^The [sqlite3_strglob(P,X)] function
+** is case sensitive.
+**
+** Note that this routine returns zero on a match and non-zero if the strings
+** do not match, the same as [sqlite3_stricmp()] and [sqlite3_strnicmp()].
+**
+** See also: [sqlite3_strlike()].
+*/
+SQLITE_API int sqlite3_strglob(const char *zGlob, const char *zStr);
+
+/*
+** CAPI3REF: String LIKE Matching
+*
+** ^The [sqlite3_strlike(P,X,E)] interface returns zero if and only if
+** string X matches the [LIKE] pattern P with escape character E.
+** ^The definition of [LIKE] pattern matching used in
+** [sqlite3_strlike(P,X,E)] is the same as for the "X LIKE P ESCAPE E"
+** operator in the SQL dialect understood by SQLite. ^For "X LIKE P" without
+** the ESCAPE clause, set the E parameter of [sqlite3_strlike(P,X,E)] to 0.
+** ^As with the LIKE operator, the [sqlite3_strlike(P,X,E)] function is case
+** insensitive - equivalent upper and lower case ASCII characters match
+** one another.
+**
+** ^The [sqlite3_strlike(P,X,E)] function matches Unicode characters, though
+** only ASCII characters are case folded.
+**
+** Note that this routine returns zero on a match and non-zero if the strings
+** do not match, the same as [sqlite3_stricmp()] and [sqlite3_strnicmp()].
+**
+** See also: [sqlite3_strglob()].
+*/
+SQLITE_API int sqlite3_strlike(const char *zGlob, const char *zStr, unsigned int cEsc);
+
+/*
+** CAPI3REF: Error Logging Interface
+**
+** ^The [sqlite3_log()] interface writes a message into the [error log]
+** established by the [SQLITE_CONFIG_LOG] option to [sqlite3_config()].
+** ^If logging is enabled, the zFormat string and subsequent arguments are
+** used with [sqlite3_snprintf()] to generate the final output string.
+**
+** The sqlite3_log() interface is intended for use by extensions such as
+** virtual tables, collating functions, and SQL functions. While there is
+** nothing to prevent an application from calling sqlite3_log(), doing so
+** is considered bad form.
+**
+** The zFormat string must not be NULL.
+**
+** To avoid deadlocks and other threading problems, the sqlite3_log() routine
+** will not use dynamically allocated memory. The log message is stored in
+** a fixed-length buffer on the stack. If the log message is longer than
+** a few hundred characters, it will be truncated to the length of the
+** buffer.
+*/
+SQLITE_API void sqlite3_log(int iErrCode, const char *zFormat, ...);
+
+/*
+** CAPI3REF: Write-Ahead Log Commit Hook
+** METHOD: sqlite3
+**
+** ^The [sqlite3_wal_hook()] function is used to register a callback that
+** is invoked each time data is committed to a database in wal mode.
+**
+** ^(The callback is invoked by SQLite after the commit has taken place and
+** the associated write-lock on the database released)^, so the implementation
+** may read, write or [checkpoint] the database as required.
+**
+** ^The first parameter passed to the callback function when it is invoked
+** is a copy of the third parameter passed to sqlite3_wal_hook() when
+** registering the callback. ^The second is a copy of the database handle.
+** ^The third parameter is the name of the database that was written to -
+** either "main" or the name of an [ATTACH]-ed database. ^The fourth parameter
+** is the number of pages currently in the write-ahead log file,
+** including those that were just committed.
+**
+** The callback function should normally return [SQLITE_OK]. ^If an error
+** code is returned, that error will propagate back up through the
+** SQLite code base to cause the statement that provoked the callback
+** to report an error, though the commit will have still occurred. If the
+** callback returns [SQLITE_ROW] or [SQLITE_DONE], or if it returns a value
+** that does not correspond to any valid SQLite error code, the results
+** are undefined.
+**
+** A single database handle may have at most a single write-ahead log callback
+** registered at one time. ^Calling [sqlite3_wal_hook()] replaces any
+** previously registered write-ahead log callback. ^Note that the
+** [sqlite3_wal_autocheckpoint()] interface and the
+** [wal_autocheckpoint pragma] both invoke [sqlite3_wal_hook()] and will
+** overwrite any prior [sqlite3_wal_hook()] settings.
+*/
+SQLITE_API void *sqlite3_wal_hook(
+ sqlite3*,
+ int(*)(void *,sqlite3*,const char*,int),
+ void*
+);
+
+/*
+** CAPI3REF: Configure an auto-checkpoint
+** METHOD: sqlite3
+**
+** ^The [sqlite3_wal_autocheckpoint(D,N)] is a wrapper around
+** [sqlite3_wal_hook()] that causes any database on [database connection] D
+** to automatically [checkpoint]
+** after committing a transaction if there are N or
+** more frames in the [write-ahead log] file. ^Passing zero or
+** a negative value as the nFrame parameter disables automatic
+** checkpoints entirely.
+**
+** ^The callback registered by this function replaces any existing callback
+** registered using [sqlite3_wal_hook()]. ^Likewise, registering a callback
+** using [sqlite3_wal_hook()] disables the automatic checkpoint mechanism
+** configured by this function.
+**
+** ^The [wal_autocheckpoint pragma] can be used to invoke this interface
+** from SQL.
+**
+** ^Checkpoints initiated by this mechanism are
+** [sqlite3_wal_checkpoint_v2|PASSIVE].
+**
+** ^Every new [database connection] defaults to having the auto-checkpoint
+** enabled with a threshold of 1000 or [SQLITE_DEFAULT_WAL_AUTOCHECKPOINT]
+** pages. The use of this interface
+** is only necessary if the default setting is found to be suboptimal
+** for a particular application.
+*/
+SQLITE_API int sqlite3_wal_autocheckpoint(sqlite3 *db, int N);
+
+/*
+** CAPI3REF: Checkpoint a database
+** METHOD: sqlite3
+**
+** ^(The sqlite3_wal_checkpoint(D,X) is equivalent to
+** [sqlite3_wal_checkpoint_v2](D,X,[SQLITE_CHECKPOINT_PASSIVE],0,0).)^
+**
+** In brief, sqlite3_wal_checkpoint(D,X) causes the content in the
+** [write-ahead log] for database X on [database connection] D to be
+** transferred into the database file and for the write-ahead log to
+** be reset. See the [checkpointing] documentation for addition
+** information.
+**
+** This interface used to be the only way to cause a checkpoint to
+** occur. But then the newer and more powerful [sqlite3_wal_checkpoint_v2()]
+** interface was added. This interface is retained for backwards
+** compatibility and as a convenience for applications that need to manually
+** start a callback but which do not need the full power (and corresponding
+** complication) of [sqlite3_wal_checkpoint_v2()].
+*/
+SQLITE_API int sqlite3_wal_checkpoint(sqlite3 *db, const char *zDb);
+
+/*
+** CAPI3REF: Checkpoint a database
+** METHOD: sqlite3
+**
+** ^(The sqlite3_wal_checkpoint_v2(D,X,M,L,C) interface runs a checkpoint
+** operation on database X of [database connection] D in mode M. Status
+** information is written back into integers pointed to by L and C.)^
+** ^(The M parameter must be a valid [checkpoint mode]:)^
+**
+** <dl>
+** <dt>SQLITE_CHECKPOINT_PASSIVE<dd>
+** ^Checkpoint as many frames as possible without waiting for any database
+** readers or writers to finish, then sync the database file if all frames
+** in the log were checkpointed. ^The [busy-handler callback]
+** is never invoked in the SQLITE_CHECKPOINT_PASSIVE mode.
+** ^On the other hand, passive mode might leave the checkpoint unfinished
+** if there are concurrent readers or writers.
+**
+** <dt>SQLITE_CHECKPOINT_FULL<dd>
+** ^This mode blocks (it invokes the
+** [sqlite3_busy_handler|busy-handler callback]) until there is no
+** database writer and all readers are reading from the most recent database
+** snapshot. ^It then checkpoints all frames in the log file and syncs the
+** database file. ^This mode blocks new database writers while it is pending,
+** but new database readers are allowed to continue unimpeded.
+**
+** <dt>SQLITE_CHECKPOINT_RESTART<dd>
+** ^This mode works the same way as SQLITE_CHECKPOINT_FULL with the addition
+** that after checkpointing the log file it blocks (calls the
+** [busy-handler callback])
+** until all readers are reading from the database file only. ^This ensures
+** that the next writer will restart the log file from the beginning.
+** ^Like SQLITE_CHECKPOINT_FULL, this mode blocks new
+** database writer attempts while it is pending, but does not impede readers.
+**
+** <dt>SQLITE_CHECKPOINT_TRUNCATE<dd>
+** ^This mode works the same way as SQLITE_CHECKPOINT_RESTART with the
+** addition that it also truncates the log file to zero bytes just prior
+** to a successful return.
+** </dl>
+**
+** ^If pnLog is not NULL, then *pnLog is set to the total number of frames in
+** the log file or to -1 if the checkpoint could not run because
+** of an error or because the database is not in [WAL mode]. ^If pnCkpt is not
+** NULL,then *pnCkpt is set to the total number of checkpointed frames in the
+** log file (including any that were already checkpointed before the function
+** was called) or to -1 if the checkpoint could not run due to an error or
+** because the database is not in WAL mode. ^Note that upon successful
+** completion of an SQLITE_CHECKPOINT_TRUNCATE, the log file will have been
+** truncated to zero bytes and so both *pnLog and *pnCkpt will be set to zero.
+**
+** ^All calls obtain an exclusive "checkpoint" lock on the database file. ^If
+** any other process is running a checkpoint operation at the same time, the
+** lock cannot be obtained and SQLITE_BUSY is returned. ^Even if there is a
+** busy-handler configured, it will not be invoked in this case.
+**
+** ^The SQLITE_CHECKPOINT_FULL, RESTART and TRUNCATE modes also obtain the
+** exclusive "writer" lock on the database file. ^If the writer lock cannot be
+** obtained immediately, and a busy-handler is configured, it is invoked and
+** the writer lock retried until either the busy-handler returns 0 or the lock
+** is successfully obtained. ^The busy-handler is also invoked while waiting for
+** database readers as described above. ^If the busy-handler returns 0 before
+** the writer lock is obtained or while waiting for database readers, the
+** checkpoint operation proceeds from that point in the same way as
+** SQLITE_CHECKPOINT_PASSIVE - checkpointing as many frames as possible
+** without blocking any further. ^SQLITE_BUSY is returned in this case.
+**
+** ^If parameter zDb is NULL or points to a zero length string, then the
+** specified operation is attempted on all WAL databases [attached] to
+** [database connection] db. In this case the
+** values written to output parameters *pnLog and *pnCkpt are undefined. ^If
+** an SQLITE_BUSY error is encountered when processing one or more of the
+** attached WAL databases, the operation is still attempted on any remaining
+** attached databases and SQLITE_BUSY is returned at the end. ^If any other
+** error occurs while processing an attached database, processing is abandoned
+** and the error code is returned to the caller immediately. ^If no error
+** (SQLITE_BUSY or otherwise) is encountered while processing the attached
+** databases, SQLITE_OK is returned.
+**
+** ^If database zDb is the name of an attached database that is not in WAL
+** mode, SQLITE_OK is returned and both *pnLog and *pnCkpt set to -1. ^If
+** zDb is not NULL (or a zero length string) and is not the name of any
+** attached database, SQLITE_ERROR is returned to the caller.
+**
+** ^Unless it returns SQLITE_MISUSE,
+** the sqlite3_wal_checkpoint_v2() interface
+** sets the error information that is queried by
+** [sqlite3_errcode()] and [sqlite3_errmsg()].
+**
+** ^The [PRAGMA wal_checkpoint] command can be used to invoke this interface
+** from SQL.
+*/
+SQLITE_API int sqlite3_wal_checkpoint_v2(
+ sqlite3 *db, /* Database handle */
+ const char *zDb, /* Name of attached database (or NULL) */
+ int eMode, /* SQLITE_CHECKPOINT_* value */
+ int *pnLog, /* OUT: Size of WAL log in frames */
+ int *pnCkpt /* OUT: Total number of frames checkpointed */
+);
+
+/*
+** CAPI3REF: Checkpoint Mode Values
+** KEYWORDS: {checkpoint mode}
+**
+** 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 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
+** various facets of the virtual table interface.
+**
+** If this interface is invoked outside the context of an xConnect or
+** xCreate virtual table method then the behavior is undefined.
+**
+** At present, there is only one option that may be configured using
+** this function. (See [SQLITE_VTAB_CONSTRAINT_SUPPORT].) Further options
+** may be added in the future.
+*/
+SQLITE_API int sqlite3_vtab_config(sqlite3*, int op, ...);
+
+/*
+** CAPI3REF: Virtual Table Configuration Options
+**
+** These macros define the various options to the
+** [sqlite3_vtab_config()] interface that [virtual table] implementations
+** can use to customize and optimize their behavior.
+**
+** <dl>
+** <dt>SQLITE_VTAB_CONSTRAINT_SUPPORT
+** <dd>Calls of the form
+** [sqlite3_vtab_config](db,SQLITE_VTAB_CONSTRAINT_SUPPORT,X) are supported,
+** where X is an integer. If X is zero, then the [virtual table] whose
+** [xCreate] or [xConnect] method invoked [sqlite3_vtab_config()] does not
+** support constraints. In this configuration (which is the default) if
+** a call to the [xUpdate] method returns [SQLITE_CONSTRAINT], then the entire
+** statement is rolled back as if [ON CONFLICT | OR ABORT] had been
+** specified as part of the users SQL statement, regardless of the actual
+** ON CONFLICT mode specified.
+**
+** If X is non-zero, then the virtual table implementation guarantees
+** that if [xUpdate] returns [SQLITE_CONSTRAINT], it will do so before
+** any modifications to internal or persistent data structures have been made.
+** If the [ON CONFLICT] mode is ABORT, FAIL, IGNORE or ROLLBACK, SQLite
+** is able to roll back a statement or database transaction, and abandon
+** or continue processing the current SQL statement as appropriate.
+** If the ON CONFLICT mode is REPLACE and the [xUpdate] method returns
+** [SQLITE_CONSTRAINT], SQLite handles this as if the ON CONFLICT mode
+** had been ABORT.
+**
+** Virtual table implementations that are required to handle OR REPLACE
+** must do so within the [xUpdate] method. If a call to the
+** [sqlite3_vtab_on_conflict()] function indicates that the current ON
+** CONFLICT policy is REPLACE, the virtual table implementation should
+** silently replace the appropriate rows within the xUpdate callback and
+** return SQLITE_OK. Or, if this is not possible, it may return
+** SQLITE_CONSTRAINT, in which case SQLite falls back to OR ABORT
+** constraint handling.
+** </dl>
+*/
+#define SQLITE_VTAB_CONSTRAINT_SUPPORT 1
+
+/*
+** CAPI3REF: Determine The Virtual Table Conflict Policy
+**
+** This function may only be called from within a call to the [xUpdate] method
+** of a [virtual table] implementation for an INSERT or UPDATE operation. ^The
+** value returned is one of [SQLITE_ROLLBACK], [SQLITE_IGNORE], [SQLITE_FAIL],
+** [SQLITE_ABORT], or [SQLITE_REPLACE], according to the [ON CONFLICT] mode
+** of the SQL statement that triggered the call to the [xUpdate] method of the
+** [virtual table].
+*/
+SQLITE_API int sqlite3_vtab_on_conflict(sqlite3 *);
+
+/*
+** CAPI3REF: Conflict resolution modes
+** KEYWORDS: {conflict resolution mode}
+**
+** These constants are returned by [sqlite3_vtab_on_conflict()] to
+** inform a [virtual table] implementation what the [ON CONFLICT] mode
+** is for the SQL statement being evaluated.
+**
+** Note that the [SQLITE_IGNORE] constant is also used as a potential
+** return value from the [sqlite3_set_authorizer()] callback and that
+** [SQLITE_ABORT] is also a [result code].
+*/
+#define SQLITE_ROLLBACK 1
+/* #define SQLITE_IGNORE 2 // Also used by sqlite3_authorizer() callback */
+#define SQLITE_FAIL 3
+/* #define SQLITE_ABORT 4 // Also an error code */
+#define SQLITE_REPLACE 5
+
+/*
+** CAPI3REF: Prepared Statement Scan Status Opcodes
+** KEYWORDS: {scanstatus options}
+**
+** The following constants can be used for the T parameter to the
+** [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.
+**
+** <dl>
+** [[SQLITE_SCANSTAT_NLOOP]] <dt>SQLITE_SCANSTAT_NLOOP</dt>
+** <dd>^The [sqlite3_int64] variable pointed to by the T 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 T parameter will be set
+** to the total number of rows examined by all iterations of the X-th loop.</dd>
+**
+** [[SQLITE_SCANSTAT_EST]] <dt>SQLITE_SCANSTAT_EST</dt>
+** <dd>^The "double" variable pointed to by the T parameter will be set to the
+** query planner's estimate for the average number of rows output from each
+** iteration of the X-th loop. If the query planner's estimates was accurate,
+** then this value will approximate the quotient NVISIT/NLOOP and the
+** product of this value for all prior loops with the same SELECTID will
+** be the NLOOP value for the current loop.
+**
+** [[SQLITE_SCANSTAT_NAME]] <dt>SQLITE_SCANSTAT_NAME</dt>
+** <dd>^The "const char *" variable pointed to by the T parameter will be set
+** to a zero-terminated UTF-8 string containing the name of the index or table
+** used for the X-th loop.
+**
+** [[SQLITE_SCANSTAT_EXPLAIN]] <dt>SQLITE_SCANSTAT_EXPLAIN</dt>
+** <dd>^The "const char *" variable pointed to by the T 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_SELECT</dt>
+** <dd>^The "int" variable pointed to by the T parameter will be set to the
+** "select-id" for the X-th loop. The select-id identifies which query or
+** subquery the loop is part of. The main query has a select-id of zero.
+** The select-id is the same value as is output in the first column
+** of an [EXPLAIN QUERY PLAN] query.
+** </dl>
+*/
+#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
+
+/*
+** CAPI3REF: Prepared Statement Scan Status
+** METHOD: sqlite3_stmt
+**
+** This interface returns 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.
+** Parameter "idx" identifies the specific loop to retrieve statistics for.
+** Loops are numbered starting from zero. ^If idx is out of range - less than
+** zero or greater than or equal to the total number of loops used to implement
+** the statement - a non-zero value is returned and the variable that pOut
+** points to is unchanged.
+**
+** ^Statistics might not be available for all loops in all statements. ^In cases
+** where there exist loops with no available statistics, this function behaves
+** as if the loop did not exist - it returns non-zero and leave the variable
+** that pOut points to 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 */
+);
+
+/*
+** CAPI3REF: Zero Scan-Status Counters
+** METHOD: sqlite3_stmt
+**
+** ^Zero all [sqlite3_stmt_scanstatus()] related event counters.
+**
+** This API is only available if the library is built with pre-processor
+** symbol [SQLITE_ENABLE_STMT_SCANSTATUS] defined.
+*/
+SQLITE_API void sqlite3_stmt_scanstatus_reset(sqlite3_stmt*);
+
+/*
+** CAPI3REF: Flush caches to disk mid-transaction
+**
+** ^If a write-transaction is open on [database connection] D when the
+** [sqlite3_db_cacheflush(D)] interface invoked, any dirty
+** pages in the pager-cache that are not currently in use are written out
+** to disk. A dirty page may be in use if a database cursor created by an
+** active SQL statement is reading from it, or if it is page 1 of a database
+** file (page 1 is always "in use"). ^The [sqlite3_db_cacheflush(D)]
+** interface flushes caches for all schemas - "main", "temp", and
+** any [attached] databases.
+**
+** ^If this function needs to obtain extra database locks before dirty pages
+** can be flushed to disk, it does so. ^If those locks cannot be obtained
+** immediately and there is a busy-handler callback configured, it is invoked
+** in the usual manner. ^If the required lock still cannot be obtained, then
+** the database is skipped and an attempt made to flush any dirty pages
+** belonging to the next (if any) database. ^If any databases are skipped
+** because locks cannot be obtained, but no other error occurs, this
+** function returns SQLITE_BUSY.
+**
+** ^If any other error occurs while flushing dirty pages to disk (for
+** example an IO error or out-of-memory condition), then processing is
+** abandoned and an SQLite [error code] is returned to the caller immediately.
+**
+** ^Otherwise, if no error occurs, [sqlite3_db_cacheflush()] returns SQLITE_OK.
+**
+** ^This function does not set the database handle error code or message
+** returned by the [sqlite3_errcode()] and [sqlite3_errmsg()] functions.
+*/
+SQLITE_API int sqlite3_db_cacheflush(sqlite3*);
+
+/*
+** CAPI3REF: The pre-update hook.
+**
+** ^These interfaces are only available if SQLite is compiled using the
+** [SQLITE_ENABLE_PREUPDATE_HOOK] compile-time option.
+**
+** ^The [sqlite3_preupdate_hook()] interface registers a callback function
+** that is invoked prior to each [INSERT], [UPDATE], and [DELETE] operation
+** on a database table.
+** ^At most one preupdate hook may be registered at a time on a single
+** [database connection]; each call to [sqlite3_preupdate_hook()] overrides
+** the previous setting.
+** ^The preupdate hook is disabled by invoking [sqlite3_preupdate_hook()]
+** with a NULL pointer as the second parameter.
+** ^The third parameter to [sqlite3_preupdate_hook()] is passed through as
+** the first parameter to callbacks.
+**
+** ^The preupdate hook only fires for changes to real database tables; the
+** preupdate hook is not invoked for changes to [virtual tables] or to
+** system tables like sqlite_master or sqlite_stat1.
+**
+** ^The second parameter to the preupdate callback is a pointer to
+** the [database connection] that registered the preupdate hook.
+** ^The third parameter to the preupdate callback is one of the constants
+** [SQLITE_INSERT], [SQLITE_DELETE], or [SQLITE_UPDATE] to identify the
+** kind of update operation that is about to occur.
+** ^(The fourth parameter to the preupdate callback is the name of the
+** database within the database connection that is being modified. This
+** will be "main" for the main database or "temp" for TEMP tables or
+** the name given after the AS keyword in the [ATTACH] statement for attached
+** databases.)^
+** ^The fifth parameter to the preupdate callback is the name of the
+** table that is being modified.
+**
+** For an UPDATE or DELETE operation on a [rowid table], the sixth
+** parameter passed to the preupdate callback is the initial [rowid] of the
+** row being modified or deleted. For an INSERT operation on a rowid table,
+** 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
+** INSERT operations on rowid tables.
+**
+** 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
+** behavior.
+**
+** ^The [sqlite3_preupdate_count(D)] interface returns the number of columns
+** in the row that is being inserted, updated, or deleted.
+**
+** ^The [sqlite3_preupdate_old(D,N,P)] interface writes into P a pointer to
+** a [protected sqlite3_value] that contains the value of the Nth column of
+** the table row before it is updated. The N parameter must be between 0
+** and one less than the number of columns or the behavior will be
+** undefined. This must only be used within SQLITE_UPDATE and SQLITE_DELETE
+** preupdate callbacks; if it is used by an SQLITE_INSERT callback then the
+** behavior is undefined. The [sqlite3_value] that P points to
+** will be destroyed when the preupdate callback returns.
+**
+** ^The [sqlite3_preupdate_new(D,N,P)] interface writes into P a pointer to
+** a [protected sqlite3_value] that contains the value of the Nth column of
+** the table row after it is updated. The N parameter must be between 0
+** and one less than the number of columns or the behavior will be
+** undefined. This must only be used within SQLITE_INSERT and SQLITE_UPDATE
+** preupdate callbacks; if it is used by an SQLITE_DELETE callback then the
+** behavior is undefined. The [sqlite3_value] that P points to
+** will be destroyed when the preupdate callback returns.
+**
+** ^The [sqlite3_preupdate_depth(D)] interface returns 0 if the preupdate
+** callback was invoked as a result of a direct insert, update, or delete
+** operation; or 1 for inserts, updates, or deletes invoked by top-level
+** triggers; or 2 for changes resulting from triggers called by top-level
+** triggers; and so forth.
+**
+** See also: [sqlite3_update_hook()]
+*/
+#if defined(SQLITE_ENABLE_PREUPDATE_HOOK)
+SQLITE_API void *sqlite3_preupdate_hook(
+ sqlite3 *db,
+ void(*xPreUpdate)(
+ void *pCtx, /* Copy of third arg to preupdate_hook() */
+ sqlite3 *db, /* Database handle */
+ int op, /* SQLITE_UPDATE, DELETE or INSERT */
+ char const *zDb, /* Database name */
+ char const *zName, /* Table name */
+ sqlite3_int64 iKey1, /* Rowid of row about to be deleted/updated */
+ sqlite3_int64 iKey2 /* New rowid value (for a rowid UPDATE) */
+ ),
+ void*
+);
+SQLITE_API int sqlite3_preupdate_old(sqlite3 *, int, sqlite3_value **);
+SQLITE_API int sqlite3_preupdate_count(sqlite3 *);
+SQLITE_API int sqlite3_preupdate_depth(sqlite3 *);
+SQLITE_API int sqlite3_preupdate_new(sqlite3 *, int, sqlite3_value **);
+#endif
+
+/*
+** CAPI3REF: Low-level system error code
+**
+** ^Attempt to return the underlying operating system error code or error
+** number that caused the most recent I/O error or failure to open a file.
+** The return value is OS-dependent. For example, on unix systems, after
+** [sqlite3_open_v2()] returns [SQLITE_CANTOPEN], this interface could be
+** called to get back the underlying "errno" that caused the problem, such
+** as ENOSPC, EAUTH, EISDIR, and so forth.
+*/
+SQLITE_API int sqlite3_system_errno(sqlite3*);
+
+/*
+** CAPI3REF: Database Snapshot
+** KEYWORDS: {snapshot} {sqlite3_snapshot}
+** EXPERIMENTAL
+**
+** An instance of the snapshot object records the state of a [WAL mode]
+** database for some specific point in history.
+**
+** In [WAL mode], multiple [database connections] that are open on the
+** same database file can each be reading a different historical version
+** of the database file. When a [database connection] begins a read
+** transaction, that connection sees an unchanging copy of the database
+** as it existed for the point in time when the transaction first started.
+** Subsequent changes to the database from other connections are not seen
+** by the reader until a new read transaction is started.
+**
+** The sqlite3_snapshot object records state information about an historical
+** version of the database file so that it is possible to later open a new read
+** transaction that sees that historical version of the database rather than
+** the most recent version.
+**
+** The constructor for this object is [sqlite3_snapshot_get()]. The
+** [sqlite3_snapshot_open()] method causes a fresh read transaction to refer
+** to an historical snapshot (if possible). The destructor for
+** sqlite3_snapshot objects is [sqlite3_snapshot_free()].
+*/
+typedef struct sqlite3_snapshot {
+ unsigned char hidden[48];
+} sqlite3_snapshot;
+
+/*
+** CAPI3REF: Record A Database Snapshot
+** EXPERIMENTAL
+**
+** ^The [sqlite3_snapshot_get(D,S,P)] interface attempts to make a
+** new [sqlite3_snapshot] object that records the current state of
+** schema S in database connection D. ^On success, the
+** [sqlite3_snapshot_get(D,S,P)] interface writes a pointer to the newly
+** created [sqlite3_snapshot] object into *P and returns SQLITE_OK.
+** If there is not already a read-transaction open on schema S when
+** this function is called, one is opened automatically.
+**
+** The following must be true for this function to succeed. If any of
+** the following statements are false when sqlite3_snapshot_get() is
+** called, SQLITE_ERROR is returned. The final value of *P is undefined
+** in this case.
+**
+** <ul>
+** <li> The database handle must be in [autocommit mode].
+**
+** <li> Schema S of [database connection] D must be a [WAL mode] database.
+**
+** <li> There must not be a write transaction open on schema S of database
+** connection D.
+**
+** <li> One or more transactions must have been written to the current wal
+** file since it was created on disk (by any connection). This means
+** that a snapshot cannot be taken on a wal mode database with no wal
+** file immediately after it is first opened. At least one transaction
+** must be written to it first.
+** </ul>
+**
+** This function may also return SQLITE_NOMEM. If it is called with the
+** database handle in autocommit mode but fails for some other reason,
+** whether or not a read transaction is opened on schema S is undefined.
+**
+** The [sqlite3_snapshot] object returned from a successful call to
+** [sqlite3_snapshot_get()] must be freed using [sqlite3_snapshot_free()]
+** to avoid a memory leak.
+**
+** The [sqlite3_snapshot_get()] interface is only available when the
+** SQLITE_ENABLE_SNAPSHOT compile-time option is used.
+*/
+SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_snapshot_get(
+ sqlite3 *db,
+ const char *zSchema,
+ sqlite3_snapshot **ppSnapshot
+);
+
+/*
+** CAPI3REF: Start a read transaction on an historical snapshot
+** EXPERIMENTAL
+**
+** ^The [sqlite3_snapshot_open(D,S,P)] interface starts a
+** read transaction for schema S of
+** [database connection] D such that the read transaction
+** refers to historical [snapshot] P, rather than the most
+** recent change to the database.
+** ^The [sqlite3_snapshot_open()] interface returns SQLITE_OK on success
+** or an appropriate [error code] if it fails.
+**
+** ^In order to succeed, a call to [sqlite3_snapshot_open(D,S,P)] must be
+** the first operation following the [BEGIN] that takes the schema S
+** out of [autocommit mode].
+** ^In other words, schema S must not currently be in
+** a transaction for [sqlite3_snapshot_open(D,S,P)] to work, but the
+** database connection D must be out of [autocommit mode].
+** ^A [snapshot] will fail to open if it has been overwritten by a
+** [checkpoint].
+** ^(A call to [sqlite3_snapshot_open(D,S,P)] will fail if the
+** database connection D does not know that the database file for
+** schema S is in [WAL mode]. A database connection might not know
+** that the database file is in [WAL mode] if there has been no prior
+** I/O on that database connection, or if the database entered [WAL mode]
+** after the most recent I/O on the database connection.)^
+** (Hint: Run "[PRAGMA application_id]" against a newly opened
+** database connection in order to make it ready to use snapshots.)
+**
+** The [sqlite3_snapshot_open()] interface is only available when the
+** SQLITE_ENABLE_SNAPSHOT compile-time option is used.
+*/
+SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_snapshot_open(
+ sqlite3 *db,
+ const char *zSchema,
+ sqlite3_snapshot *pSnapshot
+);
+
+/*
+** CAPI3REF: Destroy a snapshot
+** EXPERIMENTAL
+**
+** ^The [sqlite3_snapshot_free(P)] interface destroys [sqlite3_snapshot] P.
+** The application must eventually free every [sqlite3_snapshot] object
+** using this routine to avoid a memory leak.
+**
+** The [sqlite3_snapshot_free()] interface is only available when the
+** SQLITE_ENABLE_SNAPSHOT compile-time option is used.
+*/
+SQLITE_API SQLITE_EXPERIMENTAL void sqlite3_snapshot_free(sqlite3_snapshot*);
+
+/*
+** CAPI3REF: Compare the ages of two snapshot handles.
+** EXPERIMENTAL
+**
+** The sqlite3_snapshot_cmp(P1, P2) interface is used to compare the ages
+** of two valid snapshot handles.
+**
+** If the two snapshot handles are not associated with the same database
+** file, the result of the comparison is undefined.
+**
+** Additionally, the result of the comparison is only valid if both of the
+** snapshot handles were obtained by calling sqlite3_snapshot_get() since the
+** last time the wal file was deleted. The wal file is deleted when the
+** database is changed back to rollback mode or when the number of database
+** clients drops to zero. If either snapshot handle was obtained before the
+** wal file was last deleted, the value returned by this function
+** is undefined.
+**
+** Otherwise, this API returns a negative value if P1 refers to an older
+** snapshot than P2, zero if the two handles refer to the same database
+** snapshot, and a positive value if P1 is a newer snapshot than P2.
+*/
+SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_snapshot_cmp(
+ sqlite3_snapshot *p1,
+ sqlite3_snapshot *p2
+);
+
+/*
+** CAPI3REF: Recover snapshots from a wal file
+** EXPERIMENTAL
+**
+** If all connections disconnect from a database file but do not perform
+** a checkpoint, the existing wal file is opened along with the database
+** file the next time the database is opened. At this point it is only
+** possible to successfully call sqlite3_snapshot_open() to open the most
+** recent snapshot of the database (the one at the head of the wal file),
+** even though the wal file may contain other valid snapshots for which
+** clients have sqlite3_snapshot handles.
+**
+** This function attempts to scan the wal file associated with database zDb
+** of database handle db and make all valid snapshots available to
+** sqlite3_snapshot_open(). It is an error if there is already a read
+** transaction open on the database, or if the database is not a wal mode
+** database.
+**
+** SQLITE_OK is returned if successful, or an SQLite error code otherwise.
+*/
+SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_snapshot_recover(sqlite3 *db, const char *zDb);
+
+/*
+** Undo the hack that converts floating point types to integer for
+** builds on processors without floating point support.
+*/
+#ifdef SQLITE_OMIT_FLOATING_POINT
+# undef double
+#endif
+
+#ifdef __cplusplus
+} /* End of the 'extern "C"' block */
+#endif
+#endif /* SQLITE3_H */
+
+/******** Begin file sqlite3rtree.h *********/
+/*
+** 2010 August 30
+**
+** 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.
+**
+*************************************************************************
+*/
+
+#ifndef _SQLITE3RTREE_H_
+#define _SQLITE3RTREE_H_
+
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+typedef struct sqlite3_rtree_geometry sqlite3_rtree_geometry;
+typedef struct sqlite3_rtree_query_info sqlite3_rtree_query_info;
+
+/* The double-precision datatype used by RTree depends on the
+** SQLITE_RTREE_INT_ONLY compile-time option.
+*/
+#ifdef SQLITE_RTREE_INT_ONLY
+ typedef sqlite3_int64 sqlite3_rtree_dbl;
+#else
+ typedef double sqlite3_rtree_dbl;
+#endif
+
+/*
+** Register a geometry callback named zGeom that can be used as part of an
+** R-Tree geometry query as follows:
+**
+** SELECT ... FROM <rtree> WHERE <rtree col> MATCH $zGeom(... params ...)
+*/
+SQLITE_API int sqlite3_rtree_geometry_callback(
+ sqlite3 *db,
+ const char *zGeom,
+ int (*xGeom)(sqlite3_rtree_geometry*, int, sqlite3_rtree_dbl*,int*),
+ void *pContext
+);
+
+
+/*
+** A pointer to a structure of the following type is passed as the first
+** argument to callbacks registered using rtree_geometry_callback().
+*/
+struct sqlite3_rtree_geometry {
+ void *pContext; /* Copy of pContext passed to s_r_g_c() */
+ int nParam; /* Size of array aParam[] */
+ sqlite3_rtree_dbl *aParam; /* Parameters passed to SQL geom function */
+ void *pUser; /* Callback implementation user data */
+ void (*xDelUser)(void *); /* Called by SQLite to clean up pUser */
+};
+
+/*
+** Register a 2nd-generation geometry callback named zScore that can be
+** used as part of an R-Tree geometry query as follows:
+**
+** SELECT ... FROM <rtree> WHERE <rtree col> MATCH $zQueryFunc(... params ...)
+*/
+SQLITE_API int sqlite3_rtree_query_callback(
+ sqlite3 *db,
+ const char *zQueryFunc,
+ int (*xQueryFunc)(sqlite3_rtree_query_info*),
+ void *pContext,
+ void (*xDestructor)(void*)
+);
+
+
+/*
+** A pointer to a structure of the following type is passed as the
+** argument to scored geometry callback registered using
+** sqlite3_rtree_query_callback().
+**
+** Note that the first 5 fields of this structure are identical to
+** sqlite3_rtree_geometry. This structure is a subclass of
+** sqlite3_rtree_geometry.
+*/
+struct sqlite3_rtree_query_info {
+ void *pContext; /* pContext from when function registered */
+ int nParam; /* Number of function parameters */
+ sqlite3_rtree_dbl *aParam; /* value of function parameters */
+ void *pUser; /* callback can use this, if desired */
+ void (*xDelUser)(void*); /* function to free pUser */
+ sqlite3_rtree_dbl *aCoord; /* Coordinates of node or entry to check */
+ unsigned int *anQueue; /* Number of pending entries in the queue */
+ int nCoord; /* Number of coordinates */
+ int iLevel; /* Level of current node or entry */
+ int mxLevel; /* The largest iLevel value in the tree */
+ sqlite3_int64 iRowid; /* Rowid for current entry */
+ sqlite3_rtree_dbl rParentScore; /* Score of parent node */
+ int eParentWithin; /* Visibility of parent node */
+ int eWithin; /* OUT: Visiblity */
+ sqlite3_rtree_dbl rScore; /* OUT: Write the score here */
+ /* The following fields are only available in 3.8.11 and later */
+ sqlite3_value **apSqlParam; /* Original SQL values of parameters */
+};
+
+/*
+** Allowed values for sqlite3_rtree_query.eWithin and .eParentWithin.
+*/
+#define NOT_WITHIN 0 /* Object completely outside of query region */
+#define PARTLY_WITHIN 1 /* Object partially overlaps query region */
+#define FULLY_WITHIN 2 /* Object fully contained within query region */
+
+
+#ifdef __cplusplus
+} /* end of the 'extern "C"' block */
+#endif
+
+#endif /* ifndef _SQLITE3RTREE_H_ */
+
+/******** End of sqlite3rtree.h *********/
+/******** Begin file sqlite3session.h *********/
+
+#if !defined(__SQLITESESSION_H_) && defined(SQLITE_ENABLE_SESSION)
+#define __SQLITESESSION_H_ 1
+
+/*
+** Make sure we can call this stuff from C++.
+*/
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+
+/*
+** CAPI3REF: Session Object Handle
+*/
+typedef struct sqlite3_session sqlite3_session;
+
+/*
+** CAPI3REF: Changeset Iterator Handle
+*/
+typedef struct sqlite3_changeset_iter sqlite3_changeset_iter;
+
+/*
+** CAPI3REF: Create A New Session Object
+**
+** Create a new session object attached to database handle db. If successful,
+** a pointer to the new object is written to *ppSession and SQLITE_OK is
+** returned. If an error occurs, *ppSession is set to NULL and an SQLite
+** error code (e.g. SQLITE_NOMEM) is returned.
+**
+** It is possible to create multiple session objects attached to a single
+** database handle.
+**
+** Session objects created using this function should be deleted using the
+** [sqlite3session_delete()] function before the database handle that they
+** are attached to is itself closed. If the database handle is closed before
+** the session object is deleted, then the results of calling any session
+** module function, including [sqlite3session_delete()] on the session object
+** are undefined.
+**
+** Because the session module uses the [sqlite3_preupdate_hook()] API, it
+** is not possible for an application to register a pre-update hook on a
+** database handle that has one or more session objects attached. Nor is
+** it possible to create a session object attached to a database handle for
+** which a pre-update hook is already defined. The results of attempting
+** either of these things are undefined.
+**
+** The session object will be used to create changesets for tables in
+** database zDb, where zDb is either "main", or "temp", or the name of an
+** attached database. It is not an error if database zDb is not attached
+** to the database when the session object is created.
+*/
+SQLITE_API int sqlite3session_create(
+ sqlite3 *db, /* Database handle */
+ const char *zDb, /* Name of db (e.g. "main") */
+ sqlite3_session **ppSession /* OUT: New session object */
+);
+
+/*
+** CAPI3REF: Delete A Session Object
+**
+** Delete a session object previously allocated using
+** [sqlite3session_create()]. Once a session object has been deleted, the
+** results of attempting to use pSession with any other session module
+** function are undefined.
+**
+** Session objects must be deleted before the database handle to which they
+** are attached is closed. Refer to the documentation for
+** [sqlite3session_create()] for details.
+*/
+SQLITE_API void sqlite3session_delete(sqlite3_session *pSession);
+
+
+/*
+** CAPI3REF: Enable Or Disable A Session Object
+**
+** Enable or disable the recording of changes by a session object. When
+** enabled, a session object records changes made to the database. When
+** disabled - it does not. A newly created session object is enabled.
+** Refer to the documentation for [sqlite3session_changeset()] for further
+** details regarding how enabling and disabling a session object affects
+** the eventual changesets.
+**
+** Passing zero to this function disables the session. Passing a value
+** greater than zero enables it. Passing a value less than zero is a
+** no-op, and may be used to query the current state of the session.
+**
+** The return value indicates the final state of the session object: 0 if
+** the session is disabled, or 1 if it is enabled.
+*/
+SQLITE_API int sqlite3session_enable(sqlite3_session *pSession, int bEnable);
+
+/*
+** CAPI3REF: Set Or Clear the Indirect Change Flag
+**
+** Each change recorded by a session object is marked as either direct or
+** indirect. A change is marked as indirect if either:
+**
+** <ul>
+** <li> The session object "indirect" flag is set when the change is
+** made, or
+** <li> The change is made by an SQL trigger or foreign key action
+** instead of directly as a result of a users SQL statement.
+** </ul>
+**
+** If a single row is affected by more than one operation within a session,
+** then the change is considered indirect if all operations meet the criteria
+** for an indirect change above, or direct otherwise.
+**
+** This function is used to set, clear or query the session object indirect
+** flag. If the second argument passed to this function is zero, then the
+** indirect flag is cleared. If it is greater than zero, the indirect flag
+** is set. Passing a value less than zero does not modify the current value
+** of the indirect flag, and may be used to query the current state of the
+** indirect flag for the specified session object.
+**
+** The return value indicates the final state of the indirect flag: 0 if
+** it is clear, or 1 if it is set.
+*/
+SQLITE_API int sqlite3session_indirect(sqlite3_session *pSession, int bIndirect);
+
+/*
+** CAPI3REF: Attach A Table To A Session Object
+**
+** If argument zTab is not NULL, then it is the name of a table to attach
+** to the session object passed as the first argument. All subsequent changes
+** made to the table while the session object is enabled will be recorded. See
+** documentation for [sqlite3session_changeset()] for further details.
+**
+** Or, if argument zTab is NULL, then changes are recorded for all tables
+** in the database. If additional tables are added to the database (by
+** executing "CREATE TABLE" statements) after this call is made, changes for
+** the new tables are also recorded.
+**
+** Changes can only be recorded for tables that have a PRIMARY KEY explicitly
+** defined as part of their CREATE TABLE statement. It does not matter if the
+** PRIMARY KEY is an "INTEGER PRIMARY KEY" (rowid alias) or not. The PRIMARY
+** KEY may consist of a single column, or may be a composite key.
+**
+** It is not an error if the named table does not exist in the database. Nor
+** is it an error if the named table does not have a PRIMARY KEY. However,
+** no changes will be recorded in either of these scenarios.
+**
+** Changes are not recorded for individual rows that have NULL values stored
+** in one or more of their PRIMARY KEY columns.
+**
+** SQLITE_OK is returned if the call completes without error. Or, if an error
+** occurs, an SQLite error code (e.g. SQLITE_NOMEM) is returned.
+*/
+SQLITE_API int sqlite3session_attach(
+ sqlite3_session *pSession, /* Session object */
+ const char *zTab /* Table name */
+);
+
+/*
+** CAPI3REF: Set a table filter on a Session Object.
+**
+** The second argument (xFilter) is the "filter callback". For changes to rows
+** in tables that are not attached to the Session object, the filter is called
+** to determine whether changes to the table's rows should be tracked or not.
+** If xFilter returns 0, changes is not tracked. Note that once a table is
+** attached, xFilter will not be called again.
+*/
+SQLITE_API void sqlite3session_table_filter(
+ sqlite3_session *pSession, /* Session object */
+ int(*xFilter)(
+ void *pCtx, /* Copy of third arg to _filter_table() */
+ const char *zTab /* Table name */
+ ),
+ void *pCtx /* First argument passed to xFilter */
+);
+
+/*
+** CAPI3REF: Generate A Changeset From A Session Object
+**
+** Obtain a changeset containing changes to the tables attached to the
+** session object passed as the first argument. If successful,
+** set *ppChangeset to point to a buffer containing the changeset
+** and *pnChangeset to the size of the changeset in bytes before returning
+** SQLITE_OK. If an error occurs, set both *ppChangeset and *pnChangeset to
+** zero and return an SQLite error code.
+**
+** A changeset consists of zero or more INSERT, UPDATE and/or DELETE changes,
+** each representing a change to a single row of an attached table. An INSERT
+** change contains the values of each field of a new database row. A DELETE
+** contains the original values of each field of a deleted database row. An
+** UPDATE change contains the original values of each field of an updated
+** database row along with the updated values for each updated non-primary-key
+** column. It is not possible for an UPDATE change to represent a change that
+** modifies the values of primary key columns. If such a change is made, it
+** is represented in a changeset as a DELETE followed by an INSERT.
+**
+** Changes are not recorded for rows that have NULL values stored in one or
+** more of their PRIMARY KEY columns. If such a row is inserted or deleted,
+** no corresponding change is present in the changesets returned by this
+** function. If an existing row with one or more NULL values stored in
+** PRIMARY KEY columns is updated so that all PRIMARY KEY columns are non-NULL,
+** only an INSERT is appears in the changeset. Similarly, if an existing row
+** with non-NULL PRIMARY KEY values is updated so that one or more of its
+** PRIMARY KEY columns are set to NULL, the resulting changeset contains a
+** DELETE change only.
+**
+** The contents of a changeset may be traversed using an iterator created
+** using the [sqlite3changeset_start()] API. A changeset may be applied to
+** a database with a compatible schema using the [sqlite3changeset_apply()]
+** API.
+**
+** Within a changeset generated by this function, all changes related to a
+** single table are grouped together. In other words, when iterating through
+** a changeset or when applying a changeset to a database, all changes related
+** to a single table are processed before moving on to the next table. Tables
+** are sorted in the same order in which they were attached (or auto-attached)
+** to the sqlite3_session object. The order in which the changes related to
+** a single table are stored is undefined.
+**
+** Following a successful call to this function, it is the responsibility of
+** the caller to eventually free the buffer that *ppChangeset points to using
+** [sqlite3_free()].
+**
+** <h3>Changeset Generation</h3>
+**
+** Once a table has been attached to a session object, the session object
+** records the primary key values of all new rows inserted into the table.
+** It also records the original primary key and other column values of any
+** deleted or updated rows. For each unique primary key value, data is only
+** recorded once - the first time a row with said primary key is inserted,
+** updated or deleted in the lifetime of the session.
+**
+** There is one exception to the previous paragraph: when a row is inserted,
+** updated or deleted, if one or more of its primary key columns contain a
+** NULL value, no record of the change is made.
+**
+** The session object therefore accumulates two types of records - those
+** that consist of primary key values only (created when the user inserts
+** a new record) and those that consist of the primary key values and the
+** original values of other table columns (created when the users deletes
+** or updates a record).
+**
+** When this function is called, the requested changeset is created using
+** both the accumulated records and the current contents of the database
+** file. Specifically:
+**
+** <ul>
+** <li> For each record generated by an insert, the database is queried
+** for a row with a matching primary key. If one is found, an INSERT
+** change is added to the changeset. If no such row is found, no change
+** is added to the changeset.
+**
+** <li> For each record generated by an update or delete, the database is
+** queried for a row with a matching primary key. If such a row is
+** found and one or more of the non-primary key fields have been
+** modified from their original values, an UPDATE change is added to
+** the changeset. Or, if no such row is found in the table, a DELETE
+** change is added to the changeset. If there is a row with a matching
+** primary key in the database, but all fields contain their original
+** values, no change is added to the changeset.
+** </ul>
+**
+** This means, amongst other things, that if a row is inserted and then later
+** deleted while a session object is active, neither the insert nor the delete
+** will be present in the changeset. Or if a row is deleted and then later a
+** row with the same primary key values inserted while a session object is
+** active, the resulting changeset will contain an UPDATE change instead of
+** a DELETE and an INSERT.
+**
+** When a session object is disabled (see the [sqlite3session_enable()] API),
+** it does not accumulate records when rows are inserted, updated or deleted.
+** This may appear to have some counter-intuitive effects if a single row
+** is written to more than once during a session. For example, if a row
+** is inserted while a session object is enabled, then later deleted while
+** the same session object is disabled, no INSERT record will appear in the
+** changeset, even though the delete took place while the session was disabled.
+** Or, if one field of a row is updated while a session is disabled, and
+** another field of the same row is updated while the session is enabled, the
+** resulting changeset will contain an UPDATE change that updates both fields.
+*/
+SQLITE_API int sqlite3session_changeset(
+ sqlite3_session *pSession, /* Session object */
+ int *pnChangeset, /* OUT: Size of buffer at *ppChangeset */
+ void **ppChangeset /* OUT: Buffer containing changeset */
+);
+
+/*
+** CAPI3REF: Load The Difference Between Tables Into A Session
+**
+** If it is not already attached to the session object passed as the first
+** argument, this function attaches table zTbl in the same manner as the
+** [sqlite3session_attach()] function. If zTbl does not exist, or if it
+** does not have a primary key, this function is a no-op (but does not return
+** an error).
+**
+** Argument zFromDb must be the name of a database ("main", "temp" etc.)
+** attached to the same database handle as the session object that contains
+** a table compatible with the table attached to the session by this function.
+** A table is considered compatible if it:
+**
+** <ul>
+** <li> Has the same name,
+** <li> Has the same set of columns declared in the same order, and
+** <li> Has the same PRIMARY KEY definition.
+** </ul>
+**
+** If the tables are not compatible, SQLITE_SCHEMA is returned. If the tables
+** are compatible but do not have any PRIMARY KEY columns, it is not an error
+** but no changes are added to the session object. As with other session
+** APIs, tables without PRIMARY KEYs are simply ignored.
+**
+** This function adds a set of changes to the session object that could be
+** used to update the table in database zFrom (call this the "from-table")
+** so that its content is the same as the table attached to the session
+** object (call this the "to-table"). Specifically:
+**
+** <ul>
+** <li> For each row (primary key) that exists in the to-table but not in
+** the from-table, an INSERT record is added to the session object.
+**
+** <li> For each row (primary key) that exists in the to-table but not in
+** the from-table, a DELETE record is added to the session object.
+**
+** <li> For each row (primary key) that exists in both tables, but features
+** different non-PK values in each, an UPDATE record is added to the
+** session.
+** </ul>
+**
+** To clarify, if this function is called and then a changeset constructed
+** using [sqlite3session_changeset()], then after applying that changeset to
+** database zFrom the contents of the two compatible tables would be
+** identical.
+**
+** It an error if database zFrom does not exist or does not contain the
+** required compatible table.
+**
+** If the operation successful, SQLITE_OK is returned. Otherwise, an SQLite
+** error code. In this case, if argument pzErrMsg is not NULL, *pzErrMsg
+** may be set to point to a buffer containing an English language error
+** message. It is the responsibility of the caller to free this buffer using
+** sqlite3_free().
+*/
+SQLITE_API int sqlite3session_diff(
+ sqlite3_session *pSession,
+ const char *zFromDb,
+ const char *zTbl,
+ char **pzErrMsg
+);
+
+
+/*
+** CAPI3REF: Generate A Patchset From A Session Object
+**
+** The differences between a patchset and a changeset are that:
+**
+** <ul>
+** <li> DELETE records consist of the primary key fields only. The
+** original values of other fields are omitted.
+** <li> The original values of any modified fields are omitted from
+** UPDATE records.
+** </ul>
+**
+** A patchset blob may be used with up to date versions of all
+** sqlite3changeset_xxx API functions except for sqlite3changeset_invert(),
+** which returns SQLITE_CORRUPT if it is passed a patchset. Similarly,
+** attempting to use a patchset blob with old versions of the
+** sqlite3changeset_xxx APIs also provokes an SQLITE_CORRUPT error.
+**
+** Because the non-primary key "old.*" fields are omitted, no
+** SQLITE_CHANGESET_DATA conflicts can be detected or reported if a patchset
+** is passed to the sqlite3changeset_apply() API. Other conflict types work
+** in the same way as for changesets.
+**
+** Changes within a patchset are ordered in the same way as for changesets
+** generated by the sqlite3session_changeset() function (i.e. all changes for
+** a single table are grouped together, tables appear in the order in which
+** they were attached to the session object).
+*/
+SQLITE_API int sqlite3session_patchset(
+ sqlite3_session *pSession, /* Session object */
+ int *pnPatchset, /* OUT: Size of buffer at *ppPatchset */
+ void **ppPatchset /* OUT: Buffer containing patchset */
+);
+
+/*
+** CAPI3REF: Test if a changeset has recorded any changes.
+**
+** Return non-zero if no changes to attached tables have been recorded by
+** the session object passed as the first argument. Otherwise, if one or
+** more changes have been recorded, return zero.
+**
+** Even if this function returns zero, it is possible that calling
+** [sqlite3session_changeset()] on the session handle may still return a
+** changeset that contains no changes. This can happen when a row in
+** an attached table is modified and then later on the original values
+** are restored. However, if this function returns non-zero, then it is
+** guaranteed that a call to sqlite3session_changeset() will return a
+** changeset containing zero changes.
+*/
+SQLITE_API int sqlite3session_isempty(sqlite3_session *pSession);
+
+/*
+** CAPI3REF: Create An Iterator To Traverse A Changeset
+**
+** Create an iterator used to iterate through the contents of a changeset.
+** If successful, *pp is set to point to the iterator handle and SQLITE_OK
+** is returned. Otherwise, if an error occurs, *pp is set to zero and an
+** SQLite error code is returned.
+**
+** The following functions can be used to advance and query a changeset
+** iterator created by this function:
+**
+** <ul>
+** <li> [sqlite3changeset_next()]
+** <li> [sqlite3changeset_op()]
+** <li> [sqlite3changeset_new()]
+** <li> [sqlite3changeset_old()]
+** </ul>
+**
+** It is the responsibility of the caller to eventually destroy the iterator
+** by passing it to [sqlite3changeset_finalize()]. The buffer containing the
+** changeset (pChangeset) must remain valid until after the iterator is
+** destroyed.
+**
+** Assuming the changeset blob was created by one of the
+** [sqlite3session_changeset()], [sqlite3changeset_concat()] or
+** [sqlite3changeset_invert()] functions, all changes within the changeset
+** that apply to a single table are grouped together. This means that when
+** an application iterates through a changeset using an iterator created by
+** this function, all changes that relate to a single table are visited
+** consecutively. There is no chance that the iterator will visit a change
+** the applies to table X, then one for table Y, and then later on visit
+** another change for table X.
+*/
+SQLITE_API int sqlite3changeset_start(
+ sqlite3_changeset_iter **pp, /* OUT: New changeset iterator handle */
+ int nChangeset, /* Size of changeset blob in bytes */
+ void *pChangeset /* Pointer to blob containing changeset */
+);
+
+
+/*
+** CAPI3REF: Advance A Changeset Iterator
+**
+** This function may only be used with iterators created by function
+** [sqlite3changeset_start()]. If it is called on an iterator passed to
+** a conflict-handler callback by [sqlite3changeset_apply()], SQLITE_MISUSE
+** is returned and the call has no effect.
+**
+** Immediately after an iterator is created by sqlite3changeset_start(), it
+** does not point to any change in the changeset. Assuming the changeset
+** is not empty, the first call to this function advances the iterator to
+** point to the first change in the changeset. Each subsequent call advances
+** the iterator to point to the next change in the changeset (if any). If
+** no error occurs and the iterator points to a valid change after a call
+** to sqlite3changeset_next() has advanced it, SQLITE_ROW is returned.
+** Otherwise, if all changes in the changeset have already been visited,
+** SQLITE_DONE is returned.
+**
+** If an error occurs, an SQLite error code is returned. Possible error
+** codes include SQLITE_CORRUPT (if the changeset buffer is corrupt) or
+** SQLITE_NOMEM.
+*/
+SQLITE_API int sqlite3changeset_next(sqlite3_changeset_iter *pIter);
+
+/*
+** CAPI3REF: Obtain The Current Operation From A Changeset Iterator
+**
+** The pIter argument passed to this function may either be an iterator
+** passed to a conflict-handler by [sqlite3changeset_apply()], or an iterator
+** created by [sqlite3changeset_start()]. In the latter case, the most recent
+** call to [sqlite3changeset_next()] must have returned [SQLITE_ROW]. If this
+** is not the case, this function returns [SQLITE_MISUSE].
+**
+** If argument pzTab is not NULL, then *pzTab is set to point to a
+** nul-terminated utf-8 encoded string containing the name of the table
+** affected by the current change. The buffer remains valid until either
+** sqlite3changeset_next() is called on the iterator or until the
+** conflict-handler function returns. If pnCol is not NULL, then *pnCol is
+** set to the number of columns in the table affected by the change. If
+** pbIncorrect is not NULL, then *pbIndirect is set to true (1) if the change
+** is an indirect change, or false (0) otherwise. See the documentation for
+** [sqlite3session_indirect()] for a description of direct and indirect
+** changes. Finally, if pOp is not NULL, then *pOp is set to one of
+** [SQLITE_INSERT], [SQLITE_DELETE] or [SQLITE_UPDATE], depending on the
+** type of change that the iterator currently points to.
+**
+** If no error occurs, SQLITE_OK is returned. If an error does occur, an
+** SQLite error code is returned. The values of the output variables may not
+** be trusted in this case.
+*/
+SQLITE_API int sqlite3changeset_op(
+ sqlite3_changeset_iter *pIter, /* Iterator object */
+ const char **pzTab, /* OUT: Pointer to table name */
+ int *pnCol, /* OUT: Number of columns in table */
+ int *pOp, /* OUT: SQLITE_INSERT, DELETE or UPDATE */
+ int *pbIndirect /* OUT: True for an 'indirect' change */
+);
+
+/*
+** CAPI3REF: Obtain The Primary Key Definition Of A Table
+**
+** For each modified table, a changeset includes the following:
+**
+** <ul>
+** <li> The number of columns in the table, and
+** <li> Which of those columns make up the tables PRIMARY KEY.
+** </ul>
+**
+** This function is used to find which columns comprise the PRIMARY KEY of
+** the table modified by the change that iterator pIter currently points to.
+** If successful, *pabPK is set to point to an array of nCol entries, where
+** nCol is the number of columns in the table. Elements of *pabPK are set to
+** 0x01 if the corresponding column is part of the tables primary key, or
+** 0x00 if it is not.
+**
+** If argument pnCol is not NULL, then *pnCol is set to the number of columns
+** in the table.
+**
+** If this function is called when the iterator does not point to a valid
+** entry, SQLITE_MISUSE is returned and the output variables zeroed. Otherwise,
+** SQLITE_OK is returned and the output variables populated as described
+** above.
+*/
+SQLITE_API int sqlite3changeset_pk(
+ sqlite3_changeset_iter *pIter, /* Iterator object */
+ unsigned char **pabPK, /* OUT: Array of boolean - true for PK cols */
+ int *pnCol /* OUT: Number of entries in output array */
+);
+
+/*
+** CAPI3REF: Obtain old.* Values From A Changeset Iterator
+**
+** The pIter argument passed to this function may either be an iterator
+** passed to a conflict-handler by [sqlite3changeset_apply()], or an iterator
+** created by [sqlite3changeset_start()]. In the latter case, the most recent
+** call to [sqlite3changeset_next()] must have returned SQLITE_ROW.
+** Furthermore, it may only be called if the type of change that the iterator
+** currently points to is either [SQLITE_DELETE] or [SQLITE_UPDATE]. Otherwise,
+** this function returns [SQLITE_MISUSE] and sets *ppValue to NULL.
+**
+** Argument iVal must be greater than or equal to 0, and less than the number
+** of columns in the table affected by the current change. Otherwise,
+** [SQLITE_RANGE] is returned and *ppValue is set to NULL.
+**
+** If successful, this function sets *ppValue to point to a protected
+** sqlite3_value object containing the iVal'th value from the vector of
+** original row values stored as part of the UPDATE or DELETE change and
+** returns SQLITE_OK. The name of the function comes from the fact that this
+** is similar to the "old.*" columns available to update or delete triggers.
+**
+** If some other error occurs (e.g. an OOM condition), an SQLite error code
+** is returned and *ppValue is set to NULL.
+*/
+SQLITE_API int sqlite3changeset_old(
+ sqlite3_changeset_iter *pIter, /* Changeset iterator */
+ int iVal, /* Column number */
+ sqlite3_value **ppValue /* OUT: Old value (or NULL pointer) */
+);
+
+/*
+** CAPI3REF: Obtain new.* Values From A Changeset Iterator
+**
+** The pIter argument passed to this function may either be an iterator
+** passed to a conflict-handler by [sqlite3changeset_apply()], or an iterator
+** created by [sqlite3changeset_start()]. In the latter case, the most recent
+** call to [sqlite3changeset_next()] must have returned SQLITE_ROW.
+** Furthermore, it may only be called if the type of change that the iterator
+** currently points to is either [SQLITE_UPDATE] or [SQLITE_INSERT]. Otherwise,
+** this function returns [SQLITE_MISUSE] and sets *ppValue to NULL.
+**
+** Argument iVal must be greater than or equal to 0, and less than the number
+** of columns in the table affected by the current change. Otherwise,
+** [SQLITE_RANGE] is returned and *ppValue is set to NULL.
+**
+** If successful, this function sets *ppValue to point to a protected
+** sqlite3_value object containing the iVal'th value from the vector of
+** new row values stored as part of the UPDATE or INSERT change and
+** returns SQLITE_OK. If the change is an UPDATE and does not include
+** a new value for the requested column, *ppValue is set to NULL and
+** SQLITE_OK returned. The name of the function comes from the fact that
+** this is similar to the "new.*" columns available to update or delete
+** triggers.
+**
+** If some other error occurs (e.g. an OOM condition), an SQLite error code
+** is returned and *ppValue is set to NULL.
+*/
+SQLITE_API int sqlite3changeset_new(
+ sqlite3_changeset_iter *pIter, /* Changeset iterator */
+ int iVal, /* Column number */
+ sqlite3_value **ppValue /* OUT: New value (or NULL pointer) */
+);
+
+/*
+** CAPI3REF: Obtain Conflicting Row Values From A Changeset Iterator
+**
+** This function should only be used with iterator objects passed to a
+** conflict-handler callback by [sqlite3changeset_apply()] with either
+** [SQLITE_CHANGESET_DATA] or [SQLITE_CHANGESET_CONFLICT]. If this function
+** is called on any other iterator, [SQLITE_MISUSE] is returned and *ppValue
+** is set to NULL.
+**
+** Argument iVal must be greater than or equal to 0, and less than the number
+** of columns in the table affected by the current change. Otherwise,
+** [SQLITE_RANGE] is returned and *ppValue is set to NULL.
+**
+** If successful, this function sets *ppValue to point to a protected
+** sqlite3_value object containing the iVal'th value from the
+** "conflicting row" associated with the current conflict-handler callback
+** and returns SQLITE_OK.
+**
+** If some other error occurs (e.g. an OOM condition), an SQLite error code
+** is returned and *ppValue is set to NULL.
+*/
+SQLITE_API int sqlite3changeset_conflict(
+ sqlite3_changeset_iter *pIter, /* Changeset iterator */
+ int iVal, /* Column number */
+ sqlite3_value **ppValue /* OUT: Value from conflicting row */
+);
+
+/*
+** CAPI3REF: Determine The Number Of Foreign Key Constraint Violations
+**
+** This function may only be called with an iterator passed to an
+** SQLITE_CHANGESET_FOREIGN_KEY conflict handler callback. In this case
+** it sets the output variable to the total number of known foreign key
+** violations in the destination database and returns SQLITE_OK.
+**
+** In all other cases this function returns SQLITE_MISUSE.
+*/
+SQLITE_API int sqlite3changeset_fk_conflicts(
+ sqlite3_changeset_iter *pIter, /* Changeset iterator */
+ int *pnOut /* OUT: Number of FK violations */
+);
+
+
+/*
+** CAPI3REF: Finalize A Changeset Iterator
+**
+** This function is used to finalize an iterator allocated with
+** [sqlite3changeset_start()].
+**
+** This function should only be called on iterators created using the
+** [sqlite3changeset_start()] function. If an application calls this
+** function with an iterator passed to a conflict-handler by
+** [sqlite3changeset_apply()], [SQLITE_MISUSE] is immediately returned and the
+** call has no effect.
+**
+** If an error was encountered within a call to an sqlite3changeset_xxx()
+** function (for example an [SQLITE_CORRUPT] in [sqlite3changeset_next()] or an
+** [SQLITE_NOMEM] in [sqlite3changeset_new()]) then an error code corresponding
+** to that error is returned by this function. Otherwise, SQLITE_OK is
+** returned. This is to allow the following pattern (pseudo-code):
+**
+** sqlite3changeset_start();
+** while( SQLITE_ROW==sqlite3changeset_next() ){
+** // Do something with change.
+** }
+** rc = sqlite3changeset_finalize();
+** if( rc!=SQLITE_OK ){
+** // An error has occurred
+** }
+*/
+SQLITE_API int sqlite3changeset_finalize(sqlite3_changeset_iter *pIter);
+
+/*
+** CAPI3REF: Invert A Changeset
+**
+** This function is used to "invert" a changeset object. Applying an inverted
+** changeset to a database reverses the effects of applying the uninverted
+** changeset. Specifically:
+**
+** <ul>
+** <li> Each DELETE change is changed to an INSERT, and
+** <li> Each INSERT change is changed to a DELETE, and
+** <li> For each UPDATE change, the old.* and new.* values are exchanged.
+** </ul>
+**
+** This function does not change the order in which changes appear within
+** the changeset. It merely reverses the sense of each individual change.
+**
+** If successful, a pointer to a buffer containing the inverted changeset
+** is stored in *ppOut, the size of the same buffer is stored in *pnOut, and
+** SQLITE_OK is returned. If an error occurs, both *pnOut and *ppOut are
+** zeroed and an SQLite error code returned.
+**
+** It is the responsibility of the caller to eventually call sqlite3_free()
+** on the *ppOut pointer to free the buffer allocation following a successful
+** call to this function.
+**
+** WARNING/TODO: This function currently assumes that the input is a valid
+** changeset. If it is not, the results are undefined.
+*/
+SQLITE_API int sqlite3changeset_invert(
+ int nIn, const void *pIn, /* Input changeset */
+ int *pnOut, void **ppOut /* OUT: Inverse of input */
+);
+
+/*
+** CAPI3REF: Concatenate Two Changeset Objects
+**
+** This function is used to concatenate two changesets, A and B, into a
+** single changeset. The result is a changeset equivalent to applying
+** changeset A followed by changeset B.
+**
+** This function combines the two input changesets using an
+** sqlite3_changegroup object. Calling it produces similar results as the
+** following code fragment:
+**
+** sqlite3_changegroup *pGrp;
+** rc = sqlite3_changegroup_new(&pGrp);
+** if( rc==SQLITE_OK ) rc = sqlite3changegroup_add(pGrp, nA, pA);
+** if( rc==SQLITE_OK ) rc = sqlite3changegroup_add(pGrp, nB, pB);
+** if( rc==SQLITE_OK ){
+** rc = sqlite3changegroup_output(pGrp, pnOut, ppOut);
+** }else{
+** *ppOut = 0;
+** *pnOut = 0;
+** }
+**
+** Refer to the sqlite3_changegroup documentation below for details.
+*/
+SQLITE_API int sqlite3changeset_concat(
+ int nA, /* Number of bytes in buffer pA */
+ void *pA, /* Pointer to buffer containing changeset A */
+ int nB, /* Number of bytes in buffer pB */
+ void *pB, /* Pointer to buffer containing changeset B */
+ int *pnOut, /* OUT: Number of bytes in output changeset */
+ void **ppOut /* OUT: Buffer containing output changeset */
+);
+
+
+/*
+** CAPI3REF: Changegroup Handle
+*/
+typedef struct sqlite3_changegroup sqlite3_changegroup;
+
+/*
+** CAPI3REF: Create A New Changegroup Object
+**
+** An sqlite3_changegroup object is used to combine two or more changesets
+** (or patchsets) into a single changeset (or patchset). A single changegroup
+** object may combine changesets or patchsets, but not both. The output is
+** always in the same format as the input.
+**
+** If successful, this function returns SQLITE_OK and populates (*pp) with
+** a pointer to a new sqlite3_changegroup object before returning. The caller
+** should eventually free the returned object using a call to
+** sqlite3changegroup_delete(). If an error occurs, an SQLite error code
+** (i.e. SQLITE_NOMEM) is returned and *pp is set to NULL.
+**
+** The usual usage pattern for an sqlite3_changegroup object is as follows:
+**
+** <ul>
+** <li> It is created using a call to sqlite3changegroup_new().
+**
+** <li> Zero or more changesets (or patchsets) are added to the object
+** by calling sqlite3changegroup_add().
+**
+** <li> The result of combining all input changesets together is obtained
+** by the application via a call to sqlite3changegroup_output().
+**
+** <li> The object is deleted using a call to sqlite3changegroup_delete().
+** </ul>
+**
+** Any number of calls to add() and output() may be made between the calls to
+** new() and delete(), and in any order.
+**
+** As well as the regular sqlite3changegroup_add() and
+** sqlite3changegroup_output() functions, also available are the streaming
+** versions sqlite3changegroup_add_strm() and sqlite3changegroup_output_strm().
+*/
+SQLITE_API int sqlite3changegroup_new(sqlite3_changegroup **pp);
+
+/*
+** CAPI3REF: Add A Changeset To A Changegroup
+**
+** Add all changes within the changeset (or patchset) in buffer pData (size
+** nData bytes) to the changegroup.
+**
+** If the buffer contains a patchset, then all prior calls to this function
+** on the same changegroup object must also have specified patchsets. Or, if
+** the buffer contains a changeset, so must have the earlier calls to this
+** function. Otherwise, SQLITE_ERROR is returned and no changes are added
+** to the changegroup.
+**
+** Rows within the changeset and changegroup are identified by the values in
+** their PRIMARY KEY columns. A change in the changeset is considered to
+** apply to the same row as a change already present in the changegroup if
+** the two rows have the same primary key.
+**
+** Changes to rows that do not already appear in the changegroup are
+** simply copied into it. Or, if both the new changeset and the changegroup
+** contain changes that apply to a single row, the final contents of the
+** changegroup depends on the type of each change, as follows:
+**
+** <table border=1 style="margin-left:8ex;margin-right:8ex">
+** <tr><th style="white-space:pre">Existing Change </th>
+** <th style="white-space:pre">New Change </th>
+** <th>Output Change
+** <tr><td>INSERT <td>INSERT <td>
+** The new change is ignored. This case does not occur if the new
+** changeset was recorded immediately after the changesets already
+** added to the changegroup.
+** <tr><td>INSERT <td>UPDATE <td>
+** The INSERT change remains in the changegroup. The values in the
+** INSERT change are modified as if the row was inserted by the
+** existing change and then updated according to the new change.
+** <tr><td>INSERT <td>DELETE <td>
+** The existing INSERT is removed from the changegroup. The DELETE is
+** not added.
+** <tr><td>UPDATE <td>INSERT <td>
+** The new change is ignored. This case does not occur if the new
+** changeset was recorded immediately after the changesets already
+** added to the changegroup.
+** <tr><td>UPDATE <td>UPDATE <td>
+** The existing UPDATE remains within the changegroup. It is amended
+** so that the accompanying values are as if the row was updated once
+** by the existing change and then again by the new change.
+** <tr><td>UPDATE <td>DELETE <td>
+** The existing UPDATE is replaced by the new DELETE within the
+** changegroup.
+** <tr><td>DELETE <td>INSERT <td>
+** If one or more of the column values in the row inserted by the
+** new change differ from those in the row deleted by the existing
+** change, the existing DELETE is replaced by an UPDATE within the
+** changegroup. Otherwise, if the inserted row is exactly the same
+** as the deleted row, the existing DELETE is simply discarded.
+** <tr><td>DELETE <td>UPDATE <td>
+** The new change is ignored. This case does not occur if the new
+** changeset was recorded immediately after the changesets already
+** added to the changegroup.
+** <tr><td>DELETE <td>DELETE <td>
+** The new change is ignored. This case does not occur if the new
+** changeset was recorded immediately after the changesets already
+** added to the changegroup.
+** </table>
+**
+** If the new changeset contains changes to a table that is already present
+** in the changegroup, then the number of columns and the position of the
+** primary key columns for the table must be consistent. If this is not the
+** case, this function fails with SQLITE_SCHEMA. If the input changeset
+** appears to be corrupt and the corruption is detected, SQLITE_CORRUPT is
+** returned. Or, if an out-of-memory condition occurs during processing, this
+** function returns SQLITE_NOMEM. In all cases, if an error occurs the
+** final contents of the changegroup is undefined.
+**
+** If no error occurs, SQLITE_OK is returned.
+*/
+SQLITE_API int sqlite3changegroup_add(sqlite3_changegroup*, int nData, void *pData);
+
+/*
+** CAPI3REF: Obtain A Composite Changeset From A Changegroup
+**
+** Obtain a buffer containing a changeset (or patchset) representing the
+** current contents of the changegroup. If the inputs to the changegroup
+** were themselves changesets, the output is a changeset. Or, if the
+** inputs were patchsets, the output is also a patchset.
+**
+** As with the output of the sqlite3session_changeset() and
+** sqlite3session_patchset() functions, all changes related to a single
+** table are grouped together in the output of this function. Tables appear
+** in the same order as for the very first changeset added to the changegroup.
+** If the second or subsequent changesets added to the changegroup contain
+** changes for tables that do not appear in the first changeset, they are
+** appended onto the end of the output changeset, again in the order in
+** which they are first encountered.
+**
+** If an error occurs, an SQLite error code is returned and the output
+** variables (*pnData) and (*ppData) are set to 0. Otherwise, SQLITE_OK
+** is returned and the output variables are set to the size of and a
+** pointer to the output buffer, respectively. In this case it is the
+** responsibility of the caller to eventually free the buffer using a
+** call to sqlite3_free().
+*/
+SQLITE_API int sqlite3changegroup_output(
+ sqlite3_changegroup*,
+ int *pnData, /* OUT: Size of output buffer in bytes */
+ void **ppData /* OUT: Pointer to output buffer */
+);
+
+/*
+** CAPI3REF: Delete A Changegroup Object
+*/
+SQLITE_API void sqlite3changegroup_delete(sqlite3_changegroup*);
+
+/*
+** CAPI3REF: Apply A Changeset To A Database
+**
+** Apply a changeset to a database. This function attempts to update the
+** "main" database attached to handle db with the changes found in the
+** changeset passed via the second and third arguments.
+**
+** The fourth argument (xFilter) passed to this function is the "filter
+** callback". If it is not NULL, then for each table affected by at least one
+** change in the changeset, the filter callback is invoked with
+** the table name as the second argument, and a copy of the context pointer
+** passed as the sixth argument to this function as the first. If the "filter
+** callback" returns zero, then no attempt is made to apply any changes to
+** the table. Otherwise, if the return value is non-zero or the xFilter
+** argument to this function is NULL, all changes related to the table are
+** attempted.
+**
+** For each table that is not excluded by the filter callback, this function
+** tests that the target database contains a compatible table. A table is
+** considered compatible if all of the following are true:
+**
+** <ul>
+** <li> The table has the same name as the name recorded in the
+** changeset, and
+** <li> The table has at least as many columns as recorded in the
+** changeset, and
+** <li> The table has primary key columns in the same position as
+** recorded in the changeset.
+** </ul>
+**
+** If there is no compatible table, it is not an error, but none of the
+** changes associated with the table are applied. A warning message is issued
+** via the sqlite3_log() mechanism with the error code SQLITE_SCHEMA. At most
+** one such warning is issued for each table in the changeset.
+**
+** For each change for which there is a compatible table, an attempt is made
+** to modify the table contents according to the UPDATE, INSERT or DELETE
+** change. If a change cannot be applied cleanly, the conflict handler
+** function passed as the fifth argument to sqlite3changeset_apply() may be
+** invoked. A description of exactly when the conflict handler is invoked for
+** each type of change is below.
+**
+** Unlike the xFilter argument, xConflict may not be passed NULL. The results
+** of passing anything other than a valid function pointer as the xConflict
+** argument are undefined.
+**
+** Each time the conflict handler function is invoked, it must return one
+** of [SQLITE_CHANGESET_OMIT], [SQLITE_CHANGESET_ABORT] or
+** [SQLITE_CHANGESET_REPLACE]. SQLITE_CHANGESET_REPLACE may only be returned
+** if the second argument passed to the conflict handler is either
+** SQLITE_CHANGESET_DATA or SQLITE_CHANGESET_CONFLICT. If the conflict-handler
+** returns an illegal value, any changes already made are rolled back and
+** the call to sqlite3changeset_apply() returns SQLITE_MISUSE. Different
+** actions are taken by sqlite3changeset_apply() depending on the value
+** returned by each invocation of the conflict-handler function. Refer to
+** the documentation for the three
+** [SQLITE_CHANGESET_OMIT|available return values] for details.
+**
+** <dl>
+** <dt>DELETE Changes<dd>
+** For each DELETE change, this function checks if the target database
+** contains a row with the same primary key value (or values) as the
+** original row values stored in the changeset. If it does, and the values
+** stored in all non-primary key columns also match the values stored in
+** the changeset the row is deleted from the target database.
+**
+** If a row with matching primary key values is found, but one or more of
+** the non-primary key fields contains a value different from the original
+** row value stored in the changeset, the conflict-handler function is
+** invoked with [SQLITE_CHANGESET_DATA] as the second argument. If the
+** database table has more columns than are recorded in the changeset,
+** only the values of those non-primary key fields are compared against
+** the current database contents - any trailing database table columns
+** are ignored.
+**
+** If no row with matching primary key values is found in the database,
+** the conflict-handler function is invoked with [SQLITE_CHANGESET_NOTFOUND]
+** passed as the second argument.
+**
+** If the DELETE operation is attempted, but SQLite returns SQLITE_CONSTRAINT
+** (which can only happen if a foreign key constraint is violated), the
+** conflict-handler function is invoked with [SQLITE_CHANGESET_CONSTRAINT]
+** passed as the second argument. This includes the case where the DELETE
+** operation is attempted because an earlier call to the conflict handler
+** function returned [SQLITE_CHANGESET_REPLACE].
+**
+** <dt>INSERT Changes<dd>
+** For each INSERT change, an attempt is made to insert the new row into
+** the database. If the changeset row contains fewer fields than the
+** database table, the trailing fields are populated with their default
+** values.
+**
+** If the attempt to insert the row fails because the database already
+** contains a row with the same primary key values, the conflict handler
+** function is invoked with the second argument set to
+** [SQLITE_CHANGESET_CONFLICT].
+**
+** If the attempt to insert the row fails because of some other constraint
+** violation (e.g. NOT NULL or UNIQUE), the conflict handler function is
+** invoked with the second argument set to [SQLITE_CHANGESET_CONSTRAINT].
+** This includes the case where the INSERT operation is re-attempted because
+** an earlier call to the conflict handler function returned
+** [SQLITE_CHANGESET_REPLACE].
+**
+** <dt>UPDATE Changes<dd>
+** For each UPDATE change, this function checks if the target database
+** contains a row with the same primary key value (or values) as the
+** original row values stored in the changeset. If it does, and the values
+** stored in all modified non-primary key columns also match the values
+** stored in the changeset the row is updated within the target database.
+**
+** If a row with matching primary key values is found, but one or more of
+** the modified non-primary key fields contains a value different from an
+** original row value stored in the changeset, the conflict-handler function
+** is invoked with [SQLITE_CHANGESET_DATA] as the second argument. Since
+** UPDATE changes only contain values for non-primary key fields that are
+** to be modified, only those fields need to match the original values to
+** avoid the SQLITE_CHANGESET_DATA conflict-handler callback.
+**
+** If no row with matching primary key values is found in the database,
+** the conflict-handler function is invoked with [SQLITE_CHANGESET_NOTFOUND]
+** passed as the second argument.
+**
+** If the UPDATE operation is attempted, but SQLite returns
+** SQLITE_CONSTRAINT, the conflict-handler function is invoked with
+** [SQLITE_CHANGESET_CONSTRAINT] passed as the second argument.
+** This includes the case where the UPDATE operation is attempted after
+** an earlier call to the conflict handler function returned
+** [SQLITE_CHANGESET_REPLACE].
+** </dl>
+**
+** It is safe to execute SQL statements, including those that write to the
+** table that the callback related to, from within the xConflict callback.
+** This can be used to further customize the applications conflict
+** resolution strategy.
+**
+** All changes made by this function are enclosed in a savepoint transaction.
+** If any other error (aside from a constraint failure when attempting to
+** write to the target database) occurs, then the savepoint transaction is
+** rolled back, restoring the target database to its original state, and an
+** SQLite error code returned.
+*/
+SQLITE_API int sqlite3changeset_apply(
+ sqlite3 *db, /* Apply change to "main" db of this handle */
+ int nChangeset, /* Size of changeset in bytes */
+ void *pChangeset, /* Changeset blob */
+ int(*xFilter)(
+ void *pCtx, /* Copy of sixth arg to _apply() */
+ const char *zTab /* Table name */
+ ),
+ int(*xConflict)(
+ void *pCtx, /* Copy of sixth arg to _apply() */
+ int eConflict, /* DATA, MISSING, CONFLICT, CONSTRAINT */
+ sqlite3_changeset_iter *p /* Handle describing change and conflict */
+ ),
+ void *pCtx /* First argument passed to xConflict */
+);
+
+/*
+** CAPI3REF: Constants Passed To The Conflict Handler
+**
+** Values that may be passed as the second argument to a conflict-handler.
+**
+** <dl>
+** <dt>SQLITE_CHANGESET_DATA<dd>
+** The conflict handler is invoked with CHANGESET_DATA as the second argument
+** when processing a DELETE or UPDATE change if a row with the required
+** PRIMARY KEY fields is present in the database, but one or more other
+** (non primary-key) fields modified by the update do not contain the
+** expected "before" values.
+**
+** The conflicting row, in this case, is the database row with the matching
+** primary key.
+**
+** <dt>SQLITE_CHANGESET_NOTFOUND<dd>
+** The conflict handler is invoked with CHANGESET_NOTFOUND as the second
+** argument when processing a DELETE or UPDATE change if a row with the
+** required PRIMARY KEY fields is not present in the database.
+**
+** There is no conflicting row in this case. The results of invoking the
+** sqlite3changeset_conflict() API are undefined.
+**
+** <dt>SQLITE_CHANGESET_CONFLICT<dd>
+** CHANGESET_CONFLICT is passed as the second argument to the conflict
+** handler while processing an INSERT change if the operation would result
+** in duplicate primary key values.
+**
+** The conflicting row in this case is the database row with the matching
+** primary key.
+**
+** <dt>SQLITE_CHANGESET_FOREIGN_KEY<dd>
+** If foreign key handling is enabled, and applying a changeset leaves the
+** database in a state containing foreign key violations, the conflict
+** handler is invoked with CHANGESET_FOREIGN_KEY as the second argument
+** exactly once before the changeset is committed. If the conflict handler
+** returns CHANGESET_OMIT, the changes, including those that caused the
+** foreign key constraint violation, are committed. Or, if it returns
+** CHANGESET_ABORT, the changeset is rolled back.
+**
+** No current or conflicting row information is provided. The only function
+** it is possible to call on the supplied sqlite3_changeset_iter handle
+** is sqlite3changeset_fk_conflicts().
+**
+** <dt>SQLITE_CHANGESET_CONSTRAINT<dd>
+** If any other constraint violation occurs while applying a change (i.e.
+** a UNIQUE, CHECK or NOT NULL constraint), the conflict handler is
+** invoked with CHANGESET_CONSTRAINT as the second argument.
+**
+** There is no conflicting row in this case. The results of invoking the
+** sqlite3changeset_conflict() API are undefined.
+**
+** </dl>
+*/
+#define SQLITE_CHANGESET_DATA 1
+#define SQLITE_CHANGESET_NOTFOUND 2
+#define SQLITE_CHANGESET_CONFLICT 3
+#define SQLITE_CHANGESET_CONSTRAINT 4
+#define SQLITE_CHANGESET_FOREIGN_KEY 5
+
+/*
+** CAPI3REF: Constants Returned By The Conflict Handler
+**
+** A conflict handler callback must return one of the following three values.
+**
+** <dl>
+** <dt>SQLITE_CHANGESET_OMIT<dd>
+** If a conflict handler returns this value no special action is taken. The
+** change that caused the conflict is not applied. The session module
+** continues to the next change in the changeset.
+**
+** <dt>SQLITE_CHANGESET_REPLACE<dd>
+** This value may only be returned if the second argument to the conflict
+** handler was SQLITE_CHANGESET_DATA or SQLITE_CHANGESET_CONFLICT. If this
+** is not the case, any changes applied so far are rolled back and the
+** call to sqlite3changeset_apply() returns SQLITE_MISUSE.
+**
+** If CHANGESET_REPLACE is returned by an SQLITE_CHANGESET_DATA conflict
+** handler, then the conflicting row is either updated or deleted, depending
+** on the type of change.
+**
+** If CHANGESET_REPLACE is returned by an SQLITE_CHANGESET_CONFLICT conflict
+** handler, then the conflicting row is removed from the database and a
+** second attempt to apply the change is made. If this second attempt fails,
+** the original row is restored to the database before continuing.
+**
+** <dt>SQLITE_CHANGESET_ABORT<dd>
+** If this value is returned, any changes applied so far are rolled back
+** and the call to sqlite3changeset_apply() returns SQLITE_ABORT.
+** </dl>
+*/
+#define SQLITE_CHANGESET_OMIT 0
+#define SQLITE_CHANGESET_REPLACE 1
+#define SQLITE_CHANGESET_ABORT 2
+
+/*
+** CAPI3REF: Streaming Versions of API functions.
+**
+** The six streaming API xxx_strm() functions serve similar purposes to the
+** corresponding non-streaming API functions:
+**
+** <table border=1 style="margin-left:8ex;margin-right:8ex">
+** <tr><th>Streaming function<th>Non-streaming equivalent</th>
+** <tr><td>sqlite3changeset_apply_strm<td>[sqlite3changeset_apply]
+** <tr><td>sqlite3changeset_concat_strm<td>[sqlite3changeset_concat]
+** <tr><td>sqlite3changeset_invert_strm<td>[sqlite3changeset_invert]
+** <tr><td>sqlite3changeset_start_strm<td>[sqlite3changeset_start]
+** <tr><td>sqlite3session_changeset_strm<td>[sqlite3session_changeset]
+** <tr><td>sqlite3session_patchset_strm<td>[sqlite3session_patchset]
+** </table>
+**
+** Non-streaming functions that accept changesets (or patchsets) as input
+** require that the entire changeset be stored in a single buffer in memory.
+** Similarly, those that return a changeset or patchset do so by returning
+** a pointer to a single large buffer allocated using sqlite3_malloc().
+** Normally this is convenient. However, if an application running in a
+** low-memory environment is required to handle very large changesets, the
+** large contiguous memory allocations required can become onerous.
+**
+** In order to avoid this problem, instead of a single large buffer, input
+** is passed to a streaming API functions by way of a callback function that
+** the sessions module invokes to incrementally request input data as it is
+** required. In all cases, a pair of API function parameters such as
+**
+** <pre>
+** int nChangeset,
+** void *pChangeset,
+** </pre>
+**
+** Is replaced by:
+**
+** <pre>
+** int (*xInput)(void *pIn, void *pData, int *pnData),
+** void *pIn,
+** </pre>
+**
+** Each time the xInput callback is invoked by the sessions module, the first
+** argument passed is a copy of the supplied pIn context pointer. The second
+** argument, pData, points to a buffer (*pnData) bytes in size. Assuming no
+** error occurs the xInput method should copy up to (*pnData) bytes of data
+** into the buffer and set (*pnData) to the actual number of bytes copied
+** before returning SQLITE_OK. If the input is completely exhausted, (*pnData)
+** should be set to zero to indicate this. Or, if an error occurs, an SQLite
+** error code should be returned. In all cases, if an xInput callback returns
+** an error, all processing is abandoned and the streaming API function
+** returns a copy of the error code to the caller.
+**
+** In the case of sqlite3changeset_start_strm(), the xInput callback may be
+** invoked by the sessions module at any point during the lifetime of the
+** iterator. If such an xInput callback returns an error, the iterator enters
+** an error state, whereby all subsequent calls to iterator functions
+** immediately fail with the same error code as returned by xInput.
+**
+** Similarly, streaming API functions that return changesets (or patchsets)
+** return them in chunks by way of a callback function instead of via a
+** pointer to a single large buffer. In this case, a pair of parameters such
+** as:
+**
+** <pre>
+** int *pnChangeset,
+** void **ppChangeset,
+** </pre>
+**
+** Is replaced by:
+**
+** <pre>
+** int (*xOutput)(void *pOut, const void *pData, int nData),
+** void *pOut
+** </pre>
+**
+** The xOutput callback is invoked zero or more times to return data to
+** the application. The first parameter passed to each call is a copy of the
+** pOut pointer supplied by the application. The second parameter, pData,
+** points to a buffer nData bytes in size containing the chunk of output
+** data being returned. If the xOutput callback successfully processes the
+** supplied data, it should return SQLITE_OK to indicate success. Otherwise,
+** it should return some other SQLite error code. In this case processing
+** is immediately abandoned and the streaming API function returns a copy
+** of the xOutput error code to the application.
+**
+** The sessions module never invokes an xOutput callback with the third
+** parameter set to a value less than or equal to zero. Other than this,
+** no guarantees are made as to the size of the chunks of data returned.
+*/
+SQLITE_API int sqlite3changeset_apply_strm(
+ sqlite3 *db, /* Apply change to "main" db of this handle */
+ int (*xInput)(void *pIn, void *pData, int *pnData), /* Input function */
+ void *pIn, /* First arg for xInput */
+ int(*xFilter)(
+ void *pCtx, /* Copy of sixth arg to _apply() */
+ const char *zTab /* Table name */
+ ),
+ int(*xConflict)(
+ void *pCtx, /* Copy of sixth arg to _apply() */
+ int eConflict, /* DATA, MISSING, CONFLICT, CONSTRAINT */
+ sqlite3_changeset_iter *p /* Handle describing change and conflict */
+ ),
+ void *pCtx /* First argument passed to xConflict */
+);
+SQLITE_API int sqlite3changeset_concat_strm(
+ int (*xInputA)(void *pIn, void *pData, int *pnData),
+ void *pInA,
+ int (*xInputB)(void *pIn, void *pData, int *pnData),
+ void *pInB,
+ int (*xOutput)(void *pOut, const void *pData, int nData),
+ void *pOut
+);
+SQLITE_API int sqlite3changeset_invert_strm(
+ int (*xInput)(void *pIn, void *pData, int *pnData),
+ void *pIn,
+ int (*xOutput)(void *pOut, const void *pData, int nData),
+ void *pOut
+);
+SQLITE_API int sqlite3changeset_start_strm(
+ sqlite3_changeset_iter **pp,
+ int (*xInput)(void *pIn, void *pData, int *pnData),
+ void *pIn
+);
+SQLITE_API int sqlite3session_changeset_strm(
+ sqlite3_session *pSession,
+ int (*xOutput)(void *pOut, const void *pData, int nData),
+ void *pOut
+);
+SQLITE_API int sqlite3session_patchset_strm(
+ sqlite3_session *pSession,
+ int (*xOutput)(void *pOut, const void *pData, int nData),
+ void *pOut
+);
+SQLITE_API int sqlite3changegroup_add_strm(sqlite3_changegroup*,
+ int (*xInput)(void *pIn, void *pData, int *pnData),
+ void *pIn
+);
+SQLITE_API int sqlite3changegroup_output_strm(sqlite3_changegroup*,
+ int (*xOutput)(void *pOut, const void *pData, int nData),
+ void *pOut
+);
+
+
+/*
+** Make sure we can call this stuff from C++.
+*/
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* !defined(__SQLITESESSION_H_) && defined(SQLITE_ENABLE_SESSION) */
+
+/******** End of sqlite3session.h *********/
+/******** Begin file fts5.h *********/
+/*
+** 2014 May 31
+**
+** 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.
+**
+******************************************************************************
+**
+** Interfaces to extend FTS5. Using the interfaces defined in this file,
+** FTS5 may be extended with:
+**
+** * custom tokenizers, and
+** * custom auxiliary functions.
+*/
+
+
+#ifndef _FTS5_H
+#define _FTS5_H
+
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/*************************************************************************
+** CUSTOM AUXILIARY FUNCTIONS
+**
+** Virtual table implementations may overload SQL functions by implementing
+** the sqlite3_module.xFindFunction() method.
+*/
+
+typedef struct Fts5ExtensionApi Fts5ExtensionApi;
+typedef struct Fts5Context Fts5Context;
+typedef struct Fts5PhraseIter Fts5PhraseIter;
+
+typedef void (*fts5_extension_function)(
+ const Fts5ExtensionApi *pApi, /* API offered by current FTS version */
+ Fts5Context *pFts, /* First arg to pass to pApi functions */
+ sqlite3_context *pCtx, /* Context for returning result/error */
+ int nVal, /* Number of values in apVal[] array */
+ sqlite3_value **apVal /* Array of trailing arguments */
+);
+
+struct Fts5PhraseIter {
+ const unsigned char *a;
+ const unsigned char *b;
+};
+
+/*
+** EXTENSION API FUNCTIONS
+**
+** xUserData(pFts):
+** Return a copy of the context pointer the extension function was
+** registered with.
+**
+** xColumnTotalSize(pFts, iCol, pnToken):
+** If parameter iCol is less than zero, set output variable *pnToken
+** to the total number of tokens in the FTS5 table. Or, if iCol is
+** non-negative but less than the number of columns in the table, return
+** the total number of tokens in column iCol, considering all rows in
+** the FTS5 table.
+**
+** If parameter iCol is greater than or equal to the number of columns
+** in the table, SQLITE_RANGE is returned. Or, if an error occurs (e.g.
+** an OOM condition or IO error), an appropriate SQLite error code is
+** returned.
+**
+** xColumnCount(pFts):
+** Return the number of columns in the table.
+**
+** xColumnSize(pFts, iCol, pnToken):
+** If parameter iCol is less than zero, set output variable *pnToken
+** to the total number of tokens in the current row. Or, if iCol is
+** non-negative but less than the number of columns in the table, set
+** *pnToken to the number of tokens in column iCol of the current row.
+**
+** If parameter iCol is greater than or equal to the number of columns
+** in the table, SQLITE_RANGE is returned. Or, if an error occurs (e.g.
+** an OOM condition or IO error), an appropriate SQLite error code is
+** returned.
+**
+** This function may be quite inefficient if used with an FTS5 table
+** created with the "columnsize=0" option.
+**
+** xColumnText:
+** This function attempts to retrieve the text of column iCol of the
+** current document. If successful, (*pz) is set to point to a buffer
+** containing the text in utf-8 encoding, (*pn) is set to the size in bytes
+** (not characters) of the buffer and SQLITE_OK is returned. Otherwise,
+** if an error occurs, an SQLite error code is returned and the final values
+** of (*pz) and (*pn) are undefined.
+**
+** xPhraseCount:
+** Returns the number of phrases in the current query expression.
+**
+** xPhraseSize:
+** Returns the number of tokens in phrase iPhrase of the query. Phrases
+** are numbered starting from zero.
+**
+** xInstCount:
+** Set *pnInst to the total number of occurrences of all phrases within
+** the query within the current row. Return SQLITE_OK if successful, or
+** an error code (i.e. SQLITE_NOMEM) if an error occurs.
+**
+** This API can be quite slow if used with an FTS5 table created with the
+** "detail=none" or "detail=column" option. If the FTS5 table is created
+** with either "detail=none" or "detail=column" and "content=" option
+** (i.e. if it is a contentless table), then this API always returns 0.
+**
+** xInst:
+** Query for the details of phrase match iIdx within the current row.
+** Phrase matches are numbered starting from zero, so the iIdx argument
+** should be greater than or equal to zero and smaller than the value
+** output by xInstCount().
+**
+** Usually, output parameter *piPhrase is set to the phrase number, *piCol
+** to the column in which it occurs and *piOff the token offset of the
+** first token of the phrase. The exception is if the table was created
+** with the offsets=0 option specified. In this case *piOff is always
+** set to -1.
+**
+** Returns SQLITE_OK if successful, or an error code (i.e. SQLITE_NOMEM)
+** if an error occurs.
+**
+** This API can be quite slow if used with an FTS5 table created with the
+** "detail=none" or "detail=column" option.
+**
+** xRowid:
+** Returns the rowid of the current row.
+**
+** xTokenize:
+** Tokenize text using the tokenizer belonging to the FTS5 table.
+**
+** xQueryPhrase(pFts5, iPhrase, pUserData, xCallback):
+** This API function is used to query the FTS table for phrase iPhrase
+** of the current query. Specifically, a query equivalent to:
+**
+** ... FROM ftstable WHERE ftstable MATCH $p ORDER BY rowid
+**
+** with $p set to a phrase equivalent to the phrase iPhrase of the
+** current query is executed. Any column filter that applies to
+** phrase iPhrase of the current query is included in $p. For each
+** row visited, the callback function passed as the fourth argument
+** is invoked. The context and API objects passed to the callback
+** function may be used to access the properties of each matched row.
+** Invoking Api.xUserData() returns a copy of the pointer passed as
+** the third argument to pUserData.
+**
+** If the callback function returns any value other than SQLITE_OK, the
+** query is abandoned and the xQueryPhrase function returns immediately.
+** If the returned value is SQLITE_DONE, xQueryPhrase returns SQLITE_OK.
+** Otherwise, the error code is propagated upwards.
+**
+** If the query runs to completion without incident, SQLITE_OK is returned.
+** Or, if some error occurs before the query completes or is aborted by
+** the callback, an SQLite error code is returned.
+**
+**
+** xSetAuxdata(pFts5, pAux, xDelete)
+**
+** Save the pointer passed as the second argument as the extension functions
+** "auxiliary data". The pointer may then be retrieved by the current or any
+** future invocation of the same fts5 extension function made as part of
+** of the same MATCH query using the xGetAuxdata() API.
+**
+** Each extension function is allocated a single auxiliary data slot for
+** each FTS query (MATCH expression). If the extension function is invoked
+** more than once for a single FTS query, then all invocations share a
+** single auxiliary data context.
+**
+** If there is already an auxiliary data pointer when this function is
+** invoked, then it is replaced by the new pointer. If an xDelete callback
+** was specified along with the original pointer, it is invoked at this
+** point.
+**
+** The xDelete callback, if one is specified, is also invoked on the
+** auxiliary data pointer after the FTS5 query has finished.
+**
+** If an error (e.g. an OOM condition) occurs within this function, an
+** the auxiliary data is set to NULL and an error code returned. If the
+** xDelete parameter was not NULL, it is invoked on the auxiliary data
+** pointer before returning.
+**
+**
+** xGetAuxdata(pFts5, bClear)
+**
+** Returns the current auxiliary data pointer for the fts5 extension
+** function. See the xSetAuxdata() method for details.
+**
+** If the bClear argument is non-zero, then the auxiliary data is cleared
+** (set to NULL) before this function returns. In this case the xDelete,
+** if any, is not invoked.
+**
+**
+** xRowCount(pFts5, pnRow)
+**
+** This function is used to retrieve the total number of rows in the table.
+** In other words, the same value that would be returned by:
+**
+** SELECT count(*) FROM ftstable;
+**
+** xPhraseFirst()
+** This function is used, along with type Fts5PhraseIter and the xPhraseNext
+** method, to iterate through all instances of a single query phrase within
+** the current row. This is the same information as is accessible via the
+** xInstCount/xInst APIs. While the xInstCount/xInst APIs are more convenient
+** to use, this API may be faster under some circumstances. To iterate
+** through instances of phrase iPhrase, use the following code:
+**
+** Fts5PhraseIter iter;
+** int iCol, iOff;
+** for(pApi->xPhraseFirst(pFts, iPhrase, &iter, &iCol, &iOff);
+** iCol>=0;
+** pApi->xPhraseNext(pFts, &iter, &iCol, &iOff)
+** ){
+** // An instance of phrase iPhrase at offset iOff of column iCol
+** }
+**
+** The Fts5PhraseIter structure is defined above. Applications should not
+** modify this structure directly - it should only be used as shown above
+** with the xPhraseFirst() and xPhraseNext() API methods (and by
+** xPhraseFirstColumn() and xPhraseNextColumn() as illustrated below).
+**
+** This API can be quite slow if used with an FTS5 table created with the
+** "detail=none" or "detail=column" option. If the FTS5 table is created
+** with either "detail=none" or "detail=column" and "content=" option
+** (i.e. if it is a contentless table), then this API always iterates
+** through an empty set (all calls to xPhraseFirst() set iCol to -1).
+**
+** xPhraseNext()
+** See xPhraseFirst above.
+**
+** xPhraseFirstColumn()
+** This function and xPhraseNextColumn() are similar to the xPhraseFirst()
+** and xPhraseNext() APIs described above. The difference is that instead
+** of iterating through all instances of a phrase in the current row, these
+** APIs are used to iterate through the set of columns in the current row
+** that contain one or more instances of a specified phrase. For example:
+**
+** Fts5PhraseIter iter;
+** int iCol;
+** for(pApi->xPhraseFirstColumn(pFts, iPhrase, &iter, &iCol);
+** iCol>=0;
+** pApi->xPhraseNextColumn(pFts, &iter, &iCol)
+** ){
+** // Column iCol contains at least one instance of phrase iPhrase
+** }
+**
+** This API can be quite slow if used with an FTS5 table created with the
+** "detail=none" option. If the FTS5 table is created with either
+** "detail=none" "content=" option (i.e. if it is a contentless table),
+** then this API always iterates through an empty set (all calls to
+** xPhraseFirstColumn() set iCol to -1).
+**
+** The information accessed using this API and its companion
+** xPhraseFirstColumn() may also be obtained using xPhraseFirst/xPhraseNext
+** (or xInst/xInstCount). The chief advantage of this API is that it is
+** significantly more efficient than those alternatives when used with
+** "detail=column" tables.
+**
+** xPhraseNextColumn()
+** See xPhraseFirstColumn above.
+*/
+struct Fts5ExtensionApi {
+ int iVersion; /* Currently always set to 3 */
+
+ void *(*xUserData)(Fts5Context*);
+
+ int (*xColumnCount)(Fts5Context*);
+ int (*xRowCount)(Fts5Context*, sqlite3_int64 *pnRow);
+ int (*xColumnTotalSize)(Fts5Context*, int iCol, sqlite3_int64 *pnToken);
+
+ int (*xTokenize)(Fts5Context*,
+ const char *pText, int nText, /* Text to tokenize */
+ void *pCtx, /* Context passed to xToken() */
+ int (*xToken)(void*, int, const char*, int, int, int) /* Callback */
+ );
+
+ int (*xPhraseCount)(Fts5Context*);
+ int (*xPhraseSize)(Fts5Context*, int iPhrase);
+
+ int (*xInstCount)(Fts5Context*, int *pnInst);
+ int (*xInst)(Fts5Context*, int iIdx, int *piPhrase, int *piCol, int *piOff);
+
+ sqlite3_int64 (*xRowid)(Fts5Context*);
+ int (*xColumnText)(Fts5Context*, int iCol, const char **pz, int *pn);
+ int (*xColumnSize)(Fts5Context*, int iCol, int *pnToken);
+
+ int (*xQueryPhrase)(Fts5Context*, int iPhrase, void *pUserData,
+ int(*)(const Fts5ExtensionApi*,Fts5Context*,void*)
+ );
+ int (*xSetAuxdata)(Fts5Context*, void *pAux, void(*xDelete)(void*));
+ void *(*xGetAuxdata)(Fts5Context*, int bClear);
+
+ int (*xPhraseFirst)(Fts5Context*, int iPhrase, Fts5PhraseIter*, int*, int*);
+ void (*xPhraseNext)(Fts5Context*, Fts5PhraseIter*, int *piCol, int *piOff);
+
+ int (*xPhraseFirstColumn)(Fts5Context*, int iPhrase, Fts5PhraseIter*, int*);
+ void (*xPhraseNextColumn)(Fts5Context*, Fts5PhraseIter*, int *piCol);
+};
+
+/*
+** CUSTOM AUXILIARY FUNCTIONS
+*************************************************************************/
+
+/*************************************************************************
+** CUSTOM TOKENIZERS
+**
+** Applications may also register custom tokenizer types. A tokenizer
+** is registered by providing fts5 with a populated instance of the
+** following structure. All structure methods must be defined, setting
+** any member of the fts5_tokenizer struct to NULL leads to undefined
+** behaviour. The structure methods are expected to function as follows:
+**
+** xCreate:
+** This function is used to allocate and initialize a tokenizer instance.
+** A tokenizer instance is required to actually tokenize text.
+**
+** The first argument passed to this function is a copy of the (void*)
+** pointer provided by the application when the fts5_tokenizer object
+** was registered with FTS5 (the third argument to xCreateTokenizer()).
+** The second and third arguments are an array of nul-terminated strings
+** containing the tokenizer arguments, if any, specified following the
+** tokenizer name as part of the CREATE VIRTUAL TABLE statement used
+** to create the FTS5 table.
+**
+** The final argument is an output variable. If successful, (*ppOut)
+** should be set to point to the new tokenizer handle and SQLITE_OK
+** returned. If an error occurs, some value other than SQLITE_OK should
+** be returned. In this case, fts5 assumes that the final value of *ppOut
+** is undefined.
+**
+** xDelete:
+** This function is invoked to delete a tokenizer handle previously
+** allocated using xCreate(). Fts5 guarantees that this function will
+** be invoked exactly once for each successful call to xCreate().
+**
+** xTokenize:
+** This function is expected to tokenize the nText byte string indicated
+** by argument pText. pText may or may not be nul-terminated. The first
+** argument passed to this function is a pointer to an Fts5Tokenizer object
+** returned by an earlier call to xCreate().
+**
+** The second argument indicates the reason that FTS5 is requesting
+** tokenization of the supplied text. This is always one of the following
+** four values:
+**
+** <ul><li> <b>FTS5_TOKENIZE_DOCUMENT</b> - A document is being inserted into
+** or removed from the FTS table. The tokenizer is being invoked to
+** determine the set of tokens to add to (or delete from) the
+** FTS index.
+**
+** <li> <b>FTS5_TOKENIZE_QUERY</b> - A MATCH query is being executed
+** against the FTS index. The tokenizer is being called to tokenize
+** a bareword or quoted string specified as part of the query.
+**
+** <li> <b>(FTS5_TOKENIZE_QUERY | FTS5_TOKENIZE_PREFIX)</b> - Same as
+** FTS5_TOKENIZE_QUERY, except that the bareword or quoted string is
+** followed by a "*" character, indicating that the last token
+** returned by the tokenizer will be treated as a token prefix.
+**
+** <li> <b>FTS5_TOKENIZE_AUX</b> - The tokenizer is being invoked to
+** satisfy an fts5_api.xTokenize() request made by an auxiliary
+** function. Or an fts5_api.xColumnSize() request made by the same
+** on a columnsize=0 database.
+** </ul>
+**
+** For each token in the input string, the supplied callback xToken() must
+** be invoked. The first argument to it should be a copy of the pointer
+** passed as the second argument to xTokenize(). The third and fourth
+** arguments are a pointer to a buffer containing the token text, and the
+** size of the token in bytes. The 4th and 5th arguments are the byte offsets
+** of the first byte of and first byte immediately following the text from
+** which the token is derived within the input.
+**
+** The second argument passed to the xToken() callback ("tflags") should
+** normally be set to 0. The exception is if the tokenizer supports
+** synonyms. In this case see the discussion below for details.
+**
+** FTS5 assumes the xToken() callback is invoked for each token in the
+** order that they occur within the input text.
+**
+** If an xToken() callback returns any value other than SQLITE_OK, then
+** the tokenization should be abandoned and the xTokenize() method should
+** immediately return a copy of the xToken() return value. Or, if the
+** input buffer is exhausted, xTokenize() should return SQLITE_OK. Finally,
+** if an error occurs with the xTokenize() implementation itself, it
+** may abandon the tokenization and return any error code other than
+** SQLITE_OK or SQLITE_DONE.
+**
+** SYNONYM SUPPORT
+**
+** Custom tokenizers may also support synonyms. Consider a case in which a
+** user wishes to query for a phrase such as "first place". Using the
+** built-in tokenizers, the FTS5 query 'first + place' will match instances
+** of "first place" within the document set, but not alternative forms
+** such as "1st place". In some applications, it would be better to match
+** all instances of "first place" or "1st place" regardless of which form
+** the user specified in the MATCH query text.
+**
+** There are several ways to approach this in FTS5:
+**
+** <ol><li> By mapping all synonyms to a single token. In this case, the
+** In the above example, this means that the tokenizer returns the
+** same token for inputs "first" and "1st". Say that token is in
+** fact "first", so that when the user inserts the document "I won
+** 1st place" entries are added to the index for tokens "i", "won",
+** "first" and "place". If the user then queries for '1st + place',
+** the tokenizer substitutes "first" for "1st" and the query works
+** as expected.
+**
+** <li> By adding multiple synonyms for a single term to the FTS index.
+** In this case, when tokenizing query text, the tokenizer may
+** provide multiple synonyms for a single term within the document.
+** FTS5 then queries the index for each synonym individually. For
+** example, faced with the query:
+**
+** <codeblock>
+** ... MATCH 'first place'</codeblock>
+**
+** the tokenizer offers both "1st" and "first" as synonyms for the
+** first token in the MATCH query and FTS5 effectively runs a query
+** similar to:
+**
+** <codeblock>
+** ... MATCH '(first OR 1st) place'</codeblock>
+**
+** except that, for the purposes of auxiliary functions, the query
+** still appears to contain just two phrases - "(first OR 1st)"
+** being treated as a single phrase.
+**
+** <li> By adding multiple synonyms for a single term to the FTS index.
+** Using this method, when tokenizing document text, the tokenizer
+** provides multiple synonyms for each token. So that when a
+** document such as "I won first place" is tokenized, entries are
+** added to the FTS index for "i", "won", "first", "1st" and
+** "place".
+**
+** This way, even if the tokenizer does not provide synonyms
+** when tokenizing query text (it should not - to do would be
+** inefficient), it doesn't matter if the user queries for
+** 'first + place' or '1st + place', as there are entires in the
+** FTS index corresponding to both forms of the first token.
+** </ol>
+**
+** Whether it is parsing document or query text, any call to xToken that
+** specifies a <i>tflags</i> argument with the FTS5_TOKEN_COLOCATED bit
+** is considered to supply a synonym for the previous token. For example,
+** when parsing the document "I won first place", a tokenizer that supports
+** synonyms would call xToken() 5 times, as follows:
+**
+** <codeblock>
+** xToken(pCtx, 0, "i", 1, 0, 1);
+** xToken(pCtx, 0, "won", 3, 2, 5);
+** xToken(pCtx, 0, "first", 5, 6, 11);
+** xToken(pCtx, FTS5_TOKEN_COLOCATED, "1st", 3, 6, 11);
+** xToken(pCtx, 0, "place", 5, 12, 17);
+**</codeblock>
+**
+** It is an error to specify the FTS5_TOKEN_COLOCATED flag the first time
+** xToken() is called. Multiple synonyms may be specified for a single token
+** by making multiple calls to xToken(FTS5_TOKEN_COLOCATED) in sequence.
+** There is no limit to the number of synonyms that may be provided for a
+** single token.
+**
+** In many cases, method (1) above is the best approach. It does not add
+** extra data to the FTS index or require FTS5 to query for multiple terms,
+** so it is efficient in terms of disk space and query speed. However, it
+** does not support prefix queries very well. If, as suggested above, the
+** token "first" is subsituted for "1st" by the tokenizer, then the query:
+**
+** <codeblock>
+** ... MATCH '1s*'</codeblock>
+**
+** will not match documents that contain the token "1st" (as the tokenizer
+** will probably not map "1s" to any prefix of "first").
+**
+** For full prefix support, method (3) may be preferred. In this case,
+** because the index contains entries for both "first" and "1st", prefix
+** queries such as 'fi*' or '1s*' will match correctly. However, because
+** extra entries are added to the FTS index, this method uses more space
+** within the database.
+**
+** Method (2) offers a midpoint between (1) and (3). Using this method,
+** a query such as '1s*' will match documents that contain the literal
+** token "1st", but not "first" (assuming the tokenizer is not able to
+** provide synonyms for prefixes). However, a non-prefix query like '1st'
+** will match against "1st" and "first". This method does not require
+** extra disk space, as no extra entries are added to the FTS index.
+** On the other hand, it may require more CPU cycles to run MATCH queries,
+** as separate queries of the FTS index are required for each synonym.
+**
+** When using methods (2) or (3), it is important that the tokenizer only
+** provide synonyms when tokenizing document text (method (2)) or query
+** text (method (3)), not both. Doing so will not cause any errors, but is
+** inefficient.
+*/
+typedef struct Fts5Tokenizer Fts5Tokenizer;
+typedef struct fts5_tokenizer fts5_tokenizer;
+struct fts5_tokenizer {
+ int (*xCreate)(void*, const char **azArg, int nArg, Fts5Tokenizer **ppOut);
+ void (*xDelete)(Fts5Tokenizer*);
+ int (*xTokenize)(Fts5Tokenizer*,
+ void *pCtx,
+ int flags, /* Mask of FTS5_TOKENIZE_* flags */
+ const char *pText, int nText,
+ int (*xToken)(
+ void *pCtx, /* Copy of 2nd argument to xTokenize() */
+ int tflags, /* Mask of FTS5_TOKEN_* flags */
+ const char *pToken, /* Pointer to buffer containing token */
+ int nToken, /* Size of token in bytes */
+ int iStart, /* Byte offset of token within input text */
+ int iEnd /* Byte offset of end of token within input text */
+ )
+ );
+};
+
+/* Flags that may be passed as the third argument to xTokenize() */
+#define FTS5_TOKENIZE_QUERY 0x0001
+#define FTS5_TOKENIZE_PREFIX 0x0002
+#define FTS5_TOKENIZE_DOCUMENT 0x0004
+#define FTS5_TOKENIZE_AUX 0x0008
+
+/* Flags that may be passed by the tokenizer implementation back to FTS5
+** as the third argument to the supplied xToken callback. */
+#define FTS5_TOKEN_COLOCATED 0x0001 /* Same position as prev. token */
+
+/*
+** END OF CUSTOM TOKENIZERS
+*************************************************************************/
+
+/*************************************************************************
+** FTS5 EXTENSION REGISTRATION API
+*/
+typedef struct fts5_api fts5_api;
+struct fts5_api {
+ int iVersion; /* Currently always set to 2 */
+
+ /* Create a new tokenizer */
+ int (*xCreateTokenizer)(
+ fts5_api *pApi,
+ const char *zName,
+ void *pContext,
+ fts5_tokenizer *pTokenizer,
+ void (*xDestroy)(void*)
+ );
+
+ /* Find an existing tokenizer */
+ int (*xFindTokenizer)(
+ fts5_api *pApi,
+ const char *zName,
+ void **ppContext,
+ fts5_tokenizer *pTokenizer
+ );
+
+ /* Create a new auxiliary function */
+ int (*xCreateFunction)(
+ fts5_api *pApi,
+ const char *zName,
+ void *pContext,
+ fts5_extension_function xFunction,
+ void (*xDestroy)(void*)
+ );
+};
+
+/*
+** END OF REGISTRATION API
+*************************************************************************/
+
+#ifdef __cplusplus
+} /* end of the 'extern "C"' block */
+#endif
+
+#endif /* _FTS5_H */
+
+/******** End of fts5.h *********/