text: /*
  ** 2006 June 7
  **
  ** The author disclaims copyright to this source code.  In place of
  ** a legal notice, here is a blessing:
  **
  **    May you do good and not evil.
  **    May you find forgiveness for yourself and forgive others.
  **    May you share freely, never taking more than you give.
  **
  *************************************************************************
  ** This file contains code used to dynamically load extensions into
  ** the SQLite library.
  */
  
  #ifndef SQLITE_CORE
    #define SQLITE_CORE 1  /* Disable the API redefinition in sqlite3ext.h */
  #endif
  #include "sqlite3ext.h"
  #include "sqliteInt.h"
  
  #ifndef SQLITE_OMIT_LOAD_EXTENSION
  /*
  ** Some API routines are omitted when various features are
  ** excluded from a build of SQLite.  Substitute a NULL pointer
  ** for any missing APIs.
  */
  #ifndef SQLITE_ENABLE_COLUMN_METADATA
  # define sqlite3_column_database_name   0
  # define sqlite3_column_database_name16 0
  # define sqlite3_column_table_name      0
  # define sqlite3_column_table_name16    0
  # define sqlite3_column_origin_name     0
  # define sqlite3_column_origin_name16   0
  #endif
  
  #ifdef SQLITE_OMIT_AUTHORIZATION
  # define sqlite3_set_authorizer         0
  #endif
  
  #ifdef SQLITE_OMIT_UTF16
  # define sqlite3_bind_text16            0
  # define sqlite3_collation_needed16     0
  # define sqlite3_column_decltype16      0
  # define sqlite3_column_name16          0
  # define sqlite3_column_text16          0
  # define sqlite3_complete16             0
  # define sqlite3_create_collation16     0
  # define sqlite3_create_function16      0
  # define sqlite3_errmsg16               0
  # define sqlite3_open16                 0
  # define sqlite3_prepare16              0
  # define sqlite3_prepare16_v2           0
  # define sqlite3_prepare16_v3           0
  # define sqlite3_result_error16         0
  # define sqlite3_result_text16          0
  # define sqlite3_result_text16be        0
  # define sqlite3_result_text16le        0
  # define sqlite3_value_text16           0
  # define sqlite3_value_text16be         0
  # define sqlite3_value_text16le         0
  # define sqlite3_column_database_name16 0
  # define sqlite3_column_table_name16    0
  # define sqlite3_column_origin_name16   0
  #endif
  
  #ifdef SQLITE_OMIT_COMPLETE
  # define sqlite3_complete 0
  # define sqlite3_complete16 0
  #endif
  
  #ifdef SQLITE_OMIT_DECLTYPE
  # define sqlite3_column_decltype16      0
  # define sqlite3_column_decltype        0
  #endif
  
  #ifdef SQLITE_OMIT_PROGRESS_CALLBACK
  # define sqlite3_progress_handler 0
  #endif
  
  #ifdef SQLITE_OMIT_VIRTUALTABLE
  # define sqlite3_create_module 0
  # define sqlite3_create_module_v2 0
  # define sqlite3_declare_vtab 0
  # define sqlite3_vtab_config 0
  # define sqlite3_vtab_on_conflict 0
  # define sqlite3_vtab_collation 0
  #endif
  
  #ifdef SQLITE_OMIT_SHARED_CACHE
  # define sqlite3_enable_shared_cache 0
  #endif
  
  #if defined(SQLITE_OMIT_TRACE) || defined(SQLITE_OMIT_DEPRECATED)
  # define sqlite3_profile       0
  # define sqlite3_trace         0
  #endif
  
  #ifdef SQLITE_OMIT_GET_TABLE
  # define sqlite3_free_table    0
  # define sqlite3_get_table     0
  #endif
  
  #ifdef SQLITE_OMIT_INCRBLOB
  #define sqlite3_bind_zeroblob  0
  #define sqlite3_blob_bytes     0
  #define sqlite3_blob_close     0
  #define sqlite3_blob_open      0
  #define sqlite3_blob_read      0
  #define sqlite3_blob_write     0
  #define sqlite3_blob_reopen    0
  #endif
  
  #if defined(SQLITE_OMIT_TRACE)
  # define sqlite3_trace_v2      0
  #endif
  
  /*
  ** The following structure contains pointers to all SQLite API routines.
  ** A pointer to this structure is passed into extensions when they are
  ** loaded so that the extension can make calls back into the SQLite
  ** library.
  **
  ** When adding new APIs, add them to the bottom of this structure
  ** in order to preserve backwards compatibility.
  **
  ** Extensions that use newer APIs should first call the
  ** sqlite3_libversion_number() to make sure that the API they
  ** intend to use is supported by the library.  Extensions should
  ** also check to make sure that the pointer to the function is
  ** not NULL before calling it.
  */
  static const sqlite3_api_routines sqlite3Apis = {
    sqlite3_aggregate_context,
  #ifndef SQLITE_OMIT_DEPRECATED
    sqlite3_aggregate_count,
  #else
    0,
  #endif
    sqlite3_bind_blob,
    sqlite3_bind_double,
    sqlite3_bind_int,
    sqlite3_bind_int64,
    sqlite3_bind_null,
    sqlite3_bind_parameter_count,
    sqlite3_bind_parameter_index,
    sqlite3_bind_parameter_name,
    sqlite3_bind_text,
    sqlite3_bind_text16,
    sqlite3_bind_value,
    sqlite3_busy_handler,
    sqlite3_busy_timeout,
    sqlite3_changes,
    sqlite3_close,
    sqlite3_collation_needed,
    sqlite3_collation_needed16,
    sqlite3_column_blob,
    sqlite3_column_bytes,
    sqlite3_column_bytes16,
    sqlite3_column_count,
    sqlite3_column_database_name,
    sqlite3_column_database_name16,
    sqlite3_column_decltype,
    sqlite3_column_decltype16,
    sqlite3_column_double,
    sqlite3_column_int,
    sqlite3_column_int64,
    sqlite3_column_name,
    sqlite3_column_name16,
    sqlite3_column_origin_name,
    sqlite3_column_origin_name16,
    sqlite3_column_table_name,
    sqlite3_column_table_name16,
    sqlite3_column_text,
    sqlite3_column_text16,
    sqlite3_column_type,
    sqlite3_column_value,
    sqlite3_commit_hook,
    sqlite3_complete,
    sqlite3_complete16,
    sqlite3_create_collation,
    sqlite3_create_collation16,
    sqlite3_create_function,
    sqlite3_create_function16,
    sqlite3_create_module,
    sqlite3_data_count,
    sqlite3_db_handle,
    sqlite3_declare_vtab,
    sqlite3_enable_shared_cache,
    sqlite3_errcode,
    sqlite3_errmsg,
    sqlite3_errmsg16,
    sqlite3_exec,
  #ifndef SQLITE_OMIT_DEPRECATED
    sqlite3_expired,
  #else
    0,
  #endif
    sqlite3_finalize,
    sqlite3_free,
    sqlite3_free_table,
    sqlite3_get_autocommit,
    sqlite3_get_auxdata,
    sqlite3_get_table,
    0,     /* Was sqlite3_global_recover(), but that function is deprecated */
    sqlite3_interrupt,
    sqlite3_last_insert_rowid,
    sqlite3_libversion,
    sqlite3_libversion_number,
    sqlite3_malloc,
    sqlite3_mprintf,
    sqlite3_open,
    sqlite3_open16,
    sqlite3_prepare,
    sqlite3_prepare16,
    sqlite3_profile,
    sqlite3_progress_handler,
    sqlite3_realloc,
    sqlite3_reset,
    sqlite3_result_blob,
    sqlite3_result_double,
    sqlite3_result_error,
    sqlite3_result_error16,
    sqlite3_result_int,
    sqlite3_result_int64,
    sqlite3_result_null,
    sqlite3_result_text,
    sqlite3_result_text16,
    sqlite3_result_text16be,
    sqlite3_result_text16le,
    sqlite3_result_value,
    sqlite3_rollback_hook,
    sqlite3_set_authorizer,
    sqlite3_set_auxdata,
    sqlite3_snprintf,
    sqlite3_step,
    sqlite3_table_column_metadata,
  #ifndef SQLITE_OMIT_DEPRECATED
    sqlite3_thread_cleanup,
  #else
    0,
  #endif
    sqlite3_total_changes,
    sqlite3_trace,
  #ifndef SQLITE_OMIT_DEPRECATED
    sqlite3_transfer_bindings,
  #else
    0,
  #endif
    sqlite3_update_hook,
    sqlite3_user_data,
    sqlite3_value_blob,
    sqlite3_value_bytes,
    sqlite3_value_bytes16,
    sqlite3_value_double,
    sqlite3_value_int,
    sqlite3_value_int64,
    sqlite3_value_numeric_type,
    sqlite3_value_text,
    sqlite3_value_text16,
    sqlite3_value_text16be,
    sqlite3_value_text16le,
    sqlite3_value_type,
    sqlite3_vmprintf,
    /*
    ** The original API set ends here.  All extensions can call any
    ** of the APIs above provided that the pointer is not NULL.  But
    ** before calling APIs that follow, extension should check the
    ** sqlite3_libversion_number() to make sure they are dealing with
    ** a library that is new enough to support that API.
    *************************************************************************
    */
    sqlite3_overload_function,
  
    /*
    ** Added after 3.3.13
    */
    sqlite3_prepare_v2,
    sqlite3_prepare16_v2,
    sqlite3_clear_bindings,
  
    /*
    ** Added for 3.4.1
    */
    sqlite3_create_module_v2,
  
    /*
    ** Added for 3.5.0
    */
    sqlite3_bind_zeroblob,
    sqlite3_blob_bytes,
    sqlite3_blob_close,
    sqlite3_blob_open,
    sqlite3_blob_read,
    sqlite3_blob_write,
    sqlite3_create_collation_v2,
    sqlite3_file_control,
    sqlite3_memory_highwater,
    sqlite3_memory_used,
  #ifdef SQLITE_MUTEX_OMIT
    0, 
    0, 
    0,
    0,
    0,
  #else
    sqlite3_mutex_alloc,
    sqlite3_mutex_enter,
    sqlite3_mutex_free,
    sqlite3_mutex_leave,
    sqlite3_mutex_try,
  #endif
    sqlite3_open_v2,
    sqlite3_release_memory,
    sqlite3_result_error_nomem,
    sqlite3_result_error_toobig,
    sqlite3_sleep,
    sqlite3_soft_heap_limit,
    sqlite3_vfs_find,
    sqlite3_vfs_register,
    sqlite3_vfs_unregister,
  
    /*
    ** Added for 3.5.8
    */
    sqlite3_threadsafe,
    sqlite3_result_zeroblob,
    sqlite3_result_error_code,
    sqlite3_test_control,
    sqlite3_randomness,
    sqlite3_context_db_handle,
  
    /*
    ** Added for 3.6.0
    */
    sqlite3_extended_result_codes,
    sqlite3_limit,
    sqlite3_next_stmt,
    sqlite3_sql,
    sqlite3_status,
  
    /*
    ** Added for 3.7.4
    */
    sqlite3_backup_finish,
    sqlite3_backup_init,
    sqlite3_backup_pagecount,
    sqlite3_backup_remaining,
    sqlite3_backup_step,
  #ifndef SQLITE_OMIT_COMPILEOPTION_DIAGS
    sqlite3_compileoption_get,
    sqlite3_compileoption_used,
  #else
    0,
    0,
  #endif
    sqlite3_create_function_v2,
    sqlite3_db_config,
    sqlite3_db_mutex,
    sqlite3_db_status,
    sqlite3_extended_errcode,
    sqlite3_log,
    sqlite3_soft_heap_limit64,
    sqlite3_sourceid,
    sqlite3_stmt_status,
    sqlite3_strnicmp,
  #ifdef SQLITE_ENABLE_UNLOCK_NOTIFY
    sqlite3_unlock_notify,
  #else
    0,
  #endif
  #ifndef SQLITE_OMIT_WAL
    sqlite3_wal_autocheckpoint,
    sqlite3_wal_checkpoint,
    sqlite3_wal_hook,
  #else
    0,
    0,
    0,
  #endif
    sqlite3_blob_reopen,
    sqlite3_vtab_config,
    sqlite3_vtab_on_conflict,
    sqlite3_close_v2,
    sqlite3_db_filename,
    sqlite3_db_readonly,
    sqlite3_db_release_memory,
    sqlite3_errstr,
    sqlite3_stmt_busy,
    sqlite3_stmt_readonly,
    sqlite3_stricmp,
    sqlite3_uri_boolean,
    sqlite3_uri_int64,
    sqlite3_uri_parameter,
    sqlite3_vsnprintf,
    sqlite3_wal_checkpoint_v2,
    /* Version 3.8.7 and later */
    sqlite3_auto_extension,
    sqlite3_bind_blob64,
    sqlite3_bind_text64,
    sqlite3_cancel_auto_extension,
    sqlite3_load_extension,
    sqlite3_malloc64,
    sqlite3_msize,
    sqlite3_realloc64,
    sqlite3_reset_auto_extension,
    sqlite3_result_blob64,
    sqlite3_result_text64,
    sqlite3_strglob,
    /* Version 3.8.11 and later */
    (sqlite3_value*(*)(const sqlite3_value*))sqlite3_value_dup,
    sqlite3_value_free,
    sqlite3_result_zeroblob64,
    sqlite3_bind_zeroblob64,
    /* Version 3.9.0 and later */
    sqlite3_value_subtype,
    sqlite3_result_subtype,
    /* Version 3.10.0 and later */
    sqlite3_status64,
    sqlite3_strlike,
    sqlite3_db_cacheflush,
    /* Version 3.12.0 and later */
    sqlite3_system_errno,
    /* Version 3.14.0 and later */
    sqlite3_trace_v2,
    sqlite3_expanded_sql,
    /* Version 3.18.0 and later */
    sqlite3_set_last_insert_rowid,
    /* Version 3.20.0 and later */
    sqlite3_prepare_v3,
    sqlite3_prepare16_v3,
    sqlite3_bind_pointer,
    sqlite3_result_pointer,
    sqlite3_value_pointer,
    /* Version 3.22.0 and later */
    sqlite3_vtab_nochange,
    sqlite3_value_nochange,
    sqlite3_vtab_collation,
    /* Version 3.24.0 and later */
    sqlite3_keyword_count,
    sqlite3_keyword_name,
    sqlite3_keyword_check,
    sqlite3_str_new,
    sqlite3_str_finish,
    sqlite3_str_appendf,
    sqlite3_str_vappendf,
    sqlite3_str_append,
    sqlite3_str_appendall,
    sqlite3_str_appendchar,
    sqlite3_str_reset,
    sqlite3_str_errcode,
    sqlite3_str_length,
    sqlite3_str_value,
    /* Version 3.25.0 and later */
    sqlite3_create_window_function,
    /* Version 3.26.0 and later */
  #ifdef SQLITE_ENABLE_NORMALIZE
    sqlite3_normalized_sql,
  #else
    0,
  #endif
    /* Version 3.28.0 and later */
    sqlite3_stmt_isexplain,
    sqlite3_value_frombind,
    /* Version 3.30.0 and later */
  #ifndef SQLITE_OMIT_VIRTUALTABLE
    sqlite3_drop_modules,
  #else
    0,
  #endif
    /* Version 3.31.0 and later */
    sqlite3_hard_heap_limit64,
    sqlite3_uri_key,
    sqlite3_filename_database,
    sqlite3_filename_journal,
    sqlite3_filename_wal,
    /* Version 3.32.0 and later */
    sqlite3_create_filename,
    sqlite3_free_filename,
  };
  
  /*
  ** Attempt to load an SQLite extension library contained in the file
  ** zFile.  The entry point is zProc.  zProc may be 0 in which case a
  ** default entry point name (sqlite3_extension_init) is used.  Use
  ** of the default name is recommended.
  **
  ** Return SQLITE_OK on success and SQLITE_ERROR if something goes wrong.
  **
  ** If an error occurs and pzErrMsg is not 0, then fill *pzErrMsg with 
  ** error message text.  The calling function should free this memory
  ** by calling sqlite3DbFree(db, ).
  */
  static int sqlite3LoadExtension(
    sqlite3 *db,          /* Load the extension into this database connection */
    const char *zFile,    /* Name of the shared library containing extension */
    const char *zProc,    /* Entry point.  Use "sqlite3_extension_init" if 0 */
    char **pzErrMsg       /* Put error message here if not 0 */
  ){
    sqlite3_vfs *pVfs = db->pVfs;
    void *handle;
    sqlite3_loadext_entry xInit;
    char *zErrmsg = 0;
    const char *zEntry;
    char *zAltEntry = 0;
    void **aHandle;
    u64 nMsg = 300 + sqlite3Strlen30(zFile);
    int ii;
    int rc;
  
    /* Shared library endings to try if zFile cannot be loaded as written */
    static const char *azEndings[] = {
  #if SQLITE_OS_WIN
       "dll"   
  #elif defined(__APPLE__)
       "dylib"
  #else
       "so"
  #endif
    };
  
  
    if( pzErrMsg ) *pzErrMsg = 0;
  
    /* Ticket #1863.  To avoid a creating security problems for older
    ** applications that relink against newer versions of SQLite, the
    ** ability to run load_extension is turned off by default.  One
    ** must call either sqlite3_enable_load_extension(db) or
    ** sqlite3_db_config(db, SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION, 1, 0)
    ** to turn on extension loading.
    */
    if( (db->flags & SQLITE_LoadExtension)==0 ){
      if( pzErrMsg ){
        *pzErrMsg = sqlite3_mprintf("not authorized");
      }
      return SQLITE_ERROR;
    }
  
    zEntry = zProc ? zProc : "sqlite3_extension_init";
  
    handle = sqlite3OsDlOpen(pVfs, zFile);
  #if SQLITE_OS_UNIX || SQLITE_OS_WIN
    for(ii=0; ii<ArraySize(azEndings) && handle==0; ii++){
      char *zAltFile = sqlite3_mprintf("%s.%s", zFile, azEndings[ii]);
      if( zAltFile==0 ) return SQLITE_NOMEM_BKPT;
      handle = sqlite3OsDlOpen(pVfs, zAltFile);
      sqlite3_free(zAltFile);
    }
  #endif
    if( handle==0 ){
      if( pzErrMsg ){
        *pzErrMsg = zErrmsg = sqlite3_malloc64(nMsg);
        if( zErrmsg ){
          sqlite3_snprintf(nMsg, zErrmsg, 
              "unable to open shared library [%s]", zFile);
          sqlite3OsDlError(pVfs, nMsg-1, zErrmsg);
        }
      }
      return SQLITE_ERROR;
    }
    xInit = (sqlite3_loadext_entry)sqlite3OsDlSym(pVfs, handle, zEntry);
  
    /* If no entry point was specified and the default legacy
    ** entry point name "sqlite3_extension_init" was not found, then
    ** construct an entry point name "sqlite3_X_init" where the X is
    ** replaced by the lowercase value of every ASCII alphabetic 
    ** character in the filename after the last "/" upto the first ".",
    ** and eliding the first three characters if they are "lib".  
    ** Examples:
    **
    **    /usr/local/lib/libExample5.4.3.so ==>  sqlite3_example_init
    **    C:/lib/mathfuncs.dll              ==>  sqlite3_mathfuncs_init
    */
    if( xInit==0 && zProc==0 ){
      int iFile, iEntry, c;
      int ncFile = sqlite3Strlen30(zFile);
      zAltEntry = sqlite3_malloc64(ncFile+30);
      if( zAltEntry==0 ){
        sqlite3OsDlClose(pVfs, handle);
        return SQLITE_NOMEM_BKPT;
      }
      memcpy(zAltEntry, "sqlite3_", 8);
      for(iFile=ncFile-1; iFile>=0 && zFile[iFile]!='/'; iFile--){}
      iFile++;
      if( sqlite3_strnicmp(zFile+iFile, "lib", 3)==0 ) iFile += 3;
      for(iEntry=8; (c = zFile[iFile])!=0 && c!='.'; iFile++){
        if( sqlite3Isalpha(c) ){
          zAltEntry[iEntry++] = (char)sqlite3UpperToLower[(unsigned)c];
        }
      }
      memcpy(zAltEntry+iEntry, "_init", 6);
      zEntry = zAltEntry;
      xInit = (sqlite3_loadext_entry)sqlite3OsDlSym(pVfs, handle, zEntry);
    }
    if( xInit==0 ){
      if( pzErrMsg ){
        nMsg += sqlite3Strlen30(zEntry);
        *pzErrMsg = zErrmsg = sqlite3_malloc64(nMsg);
        if( zErrmsg ){
          sqlite3_snprintf(nMsg, zErrmsg,
              "no entry point [%s] in shared library [%s]", zEntry, zFile);
          sqlite3OsDlError(pVfs, nMsg-1, zErrmsg);
        }
      }
      sqlite3OsDlClose(pVfs, handle);
      sqlite3_free(zAltEntry);
      return SQLITE_ERROR;
    }
    sqlite3_free(zAltEntry);
    rc = xInit(db, &zErrmsg, &sqlite3Apis);
    if( rc ){
      if( rc==SQLITE_OK_LOAD_PERMANENTLY ) return SQLITE_OK;
      if( pzErrMsg ){
        *pzErrMsg = sqlite3_mprintf("error during initialization: %s", zErrmsg);
      }
      sqlite3_free(zErrmsg);
      sqlite3OsDlClose(pVfs, handle);
      return SQLITE_ERROR;
    }
  
    /* Append the new shared library handle to the db->aExtension array. */
    aHandle = sqlite3DbMallocZero(db, sizeof(handle)*(db->nExtension+1));
    if( aHandle==0 ){
      return SQLITE_NOMEM_BKPT;
    }
    if( db->nExtension>0 ){
      memcpy(aHandle, db->aExtension, sizeof(handle)*db->nExtension);
    }
    sqlite3DbFree(db, db->aExtension);
    db->aExtension = aHandle;
  
    db->aExtension[db->nExtension++] = handle;
    return SQLITE_OK;
  }
  int sqlite3_load_extension(
    sqlite3 *db,          /* Load the extension into this database connection */
    const char *zFile,    /* Name of the shared library containing extension */
    const char *zProc,    /* Entry point.  Use "sqlite3_extension_init" if 0 */
    char **pzErrMsg       /* Put error message here if not 0 */
  ){
    int rc;
    sqlite3_mutex_enter(db->mutex);
    rc = sqlite3LoadExtension(db, zFile, zProc, pzErrMsg);
    rc = sqlite3ApiExit(db, rc);
    sqlite3_mutex_leave(db->mutex);
    return rc;
  }
  
  /*
  ** Call this routine when the database connection is closing in order
  ** to clean up loaded extensions
  */
  void sqlite3CloseExtensions(sqlite3 *db){
    int i;
    assert( sqlite3_mutex_held(db->mutex) );
    for(i=0; i<db->nExtension; i++){
      sqlite3OsDlClose(db->pVfs, db->aExtension[i]);
    }
    sqlite3DbFree(db, db->aExtension);
  }
  
  /*
  ** Enable or disable extension loading.  Extension loading is disabled by
  ** default so as not to open security holes in older applications.
  */
  int sqlite3_enable_load_extension(sqlite3 *db, int onoff){
    sqlite3_mutex_enter(db->mutex);
    if( onoff ){
      db->flags |= SQLITE_LoadExtension|SQLITE_LoadExtFunc;
    }else{
      db->flags &= ~(u64)(SQLITE_LoadExtension|SQLITE_LoadExtFunc);
    }
    sqlite3_mutex_leave(db->mutex);
    return SQLITE_OK;
  }
  
  #endif /* !defined(SQLITE_OMIT_LOAD_EXTENSION) */
  
  /*
  ** The following object holds the list of automatically loaded
  ** extensions.
  **
  ** This list is shared across threads.  The SQLITE_MUTEX_STATIC_MASTER
  ** mutex must be held while accessing this list.
  */
  typedef struct sqlite3AutoExtList sqlite3AutoExtList;
  static SQLITE_WSD struct sqlite3AutoExtList {
    u32 nExt;              /* Number of entries in aExt[] */          
    void (**aExt)(void);   /* Pointers to the extension init functions */
  } sqlite3Autoext = { 0, 0 };
  
  /* The "wsdAutoext" macro will resolve to the autoextension
  ** state vector.  If writable static data is unsupported on the target,
  ** we have to locate the state vector at run-time.  In the more common
  ** case where writable static data is supported, wsdStat can refer directly
  ** to the "sqlite3Autoext" state vector declared above.
  */
  #ifdef SQLITE_OMIT_WSD
  # define wsdAutoextInit \
    sqlite3AutoExtList *x = &GLOBAL(sqlite3AutoExtList,sqlite3Autoext)
  # define wsdAutoext x[0]
  #else
  # define wsdAutoextInit
  # define wsdAutoext sqlite3Autoext
  #endif
  
  
  /*
  ** Register a statically linked extension that is automatically
  ** loaded by every new database connection.
  */
  int sqlite3_auto_extension(
    void (*xInit)(void)
  ){
    int rc = SQLITE_OK;
  #ifndef SQLITE_OMIT_AUTOINIT
    rc = sqlite3_initialize();
    if( rc ){
      return rc;
    }else
  #endif
    {
      u32 i;
  #if SQLITE_THREADSAFE
      sqlite3_mutex *mutex = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER);
  #endif
      wsdAutoextInit;
      sqlite3_mutex_enter(mutex);
      for(i=0; i<wsdAutoext.nExt; i++){
        if( wsdAutoext.aExt[i]==xInit ) break;
      }
      if( i==wsdAutoext.nExt ){
        u64 nByte = (wsdAutoext.nExt+1)*sizeof(wsdAutoext.aExt[0]);
        void (**aNew)(void);
        aNew = sqlite3_realloc64(wsdAutoext.aExt, nByte);
        if( aNew==0 ){
          rc = SQLITE_NOMEM_BKPT;
        }else{
          wsdAutoext.aExt = aNew;
          wsdAutoext.aExt[wsdAutoext.nExt] = xInit;
          wsdAutoext.nExt++;
        }
      }
      sqlite3_mutex_leave(mutex);
      assert( (rc&0xff)==rc );
      return rc;
    }
  }
  
  /*
  ** Cancel a prior call to sqlite3_auto_extension.  Remove xInit from the
  ** set of routines that is invoked for each new database connection, if it
  ** is currently on the list.  If xInit is not on the list, then this
  ** routine is a no-op.
  **
  ** Return 1 if xInit was found on the list and removed.  Return 0 if xInit
  ** was not on the list.
  */
  int sqlite3_cancel_auto_extension(
    void (*xInit)(void)
  ){
  #if SQLITE_THREADSAFE
    sqlite3_mutex *mutex = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER);
  #endif
    int i;
    int n = 0;
    wsdAutoextInit;
    sqlite3_mutex_enter(mutex);
    for(i=(int)wsdAutoext.nExt-1; i>=0; i--){
      if( wsdAutoext.aExt[i]==xInit ){
        wsdAutoext.nExt--;
        wsdAutoext.aExt[i] = wsdAutoext.aExt[wsdAutoext.nExt];
        n++;
        break;
      }
    }
    sqlite3_mutex_leave(mutex);
    return n;
  }
  
  /*
  ** Reset the automatic extension loading mechanism.
  */
  void sqlite3_reset_auto_extension(void){
  #ifndef SQLITE_OMIT_AUTOINIT
    if( sqlite3_initialize()==SQLITE_OK )
  #endif
    {
  #if SQLITE_THREADSAFE
      sqlite3_mutex *mutex = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER);
  #endif
      wsdAutoextInit;
      sqlite3_mutex_enter(mutex);
      sqlite3_free(wsdAutoext.aExt);
      wsdAutoext.aExt = 0;
      wsdAutoext.nExt = 0;
      sqlite3_mutex_leave(mutex);
    }
  }
  
  /*
  ** Load all automatic extensions.
  **
  ** If anything goes wrong, set an error in the database connection.
  */
  void sqlite3AutoLoadExtensions(sqlite3 *db){
    u32 i;
    int go = 1;
    int rc;
    sqlite3_loadext_entry xInit;
  
    wsdAutoextInit;
    if( wsdAutoext.nExt==0 ){
      /* Common case: early out without every having to acquire a mutex */
      return;
    }
    for(i=0; go; i++){
      char *zErrmsg;
  #if SQLITE_THREADSAFE
      sqlite3_mutex *mutex = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER);
  #endif
  #ifdef SQLITE_OMIT_LOAD_EXTENSION
      const sqlite3_api_routines *pThunk = 0;
  #else
      const sqlite3_api_routines *pThunk = &sqlite3Apis;
  #endif
      sqlite3_mutex_enter(mutex);
      if( i>=wsdAutoext.nExt ){
        xInit = 0;
        go = 0;
      }else{
        xInit = (sqlite3_loadext_entry)wsdAutoext.aExt[i];
      }
      sqlite3_mutex_leave(mutex);
      zErrmsg = 0;
      if( xInit && (rc = xInit(db, &zErrmsg, pThunk))!=0 ){
        sqlite3ErrorWithMsg(db, rc,
              "automatic extension loading failed: %s", zErrmsg);
        go = 0;
      }
      sqlite3_free(zErrmsg);
    }
  }
  