예제 #1
0
/*
** Implementation of a special SQL scalar function for testing tokenizers 
** designed to be used in concert with the Tcl testing framework. This
** function must be called with two or more arguments:
**
**   SELECT <function-name>(<key-name>, ..., <input-string>);
**
** where <function-name> is the name passed as the second argument
** to the sqlite3Fts3InitHashTable() function (e.g. 'fts3_tokenizer')
** concatenated with the string '_test' (e.g. 'fts3_tokenizer_test').
**
** The return value is a string that may be interpreted as a Tcl
** list. For each token in the <input-string>, three elements are
** added to the returned list. The first is the token position, the 
** second is the token text (folded, stemmed, etc.) and the third is the
** substring of <input-string> associated with the token. For example, 
** using the built-in "simple" tokenizer:
**
**   SELECT fts_tokenizer_test('simple', 'I don't see how');
**
** will return the string:
**
**   "{0 i I 1 dont don't 2 see see 3 how how}"
**   
*/
static void testFunc(
  sqlite3_context *context,
  int argc,
  sqlite3_value **argv
){
  Fts3Hash *pHash;
  sqlite3_tokenizer_module *p;
  sqlite3_tokenizer *pTokenizer = 0;
  sqlite3_tokenizer_cursor *pCsr = 0;

  const char *zErr = 0;

  const char *zName;
  int nName;
  const char *zInput;
  int nInput;

  const char *azArg[64];

  const char *zToken;
  int nToken = 0;
  int iStart = 0;
  int iEnd = 0;
  int iPos = 0;
  int i;

  Tcl_Obj *pRet;

  if( argc<2 ){
    sqlite3_result_error(context, "insufficient arguments", -1);
    return;
  }

  nName = sqlite3_value_bytes(argv[0]);
  zName = (const char *)sqlite3_value_text(argv[0]);
  nInput = sqlite3_value_bytes(argv[argc-1]);
  zInput = (const char *)sqlite3_value_text(argv[argc-1]);

  pHash = (Fts3Hash *)sqlite3_user_data(context);
  p = (sqlite3_tokenizer_module *)sqlite3Fts3HashFind(pHash, zName, nName+1);

  if( !p ){
    char *zErr = sqlite3_mprintf("unknown tokenizer: %s", zName);
    sqlite3_result_error(context, zErr, -1);
    sqlite3_free(zErr);
    return;
  }

  pRet = Tcl_NewObj();
  Tcl_IncrRefCount(pRet);

  for(i=1; i<argc-1; i++){
    azArg[i-1] = (const char *)sqlite3_value_text(argv[i]);
  }

  if( SQLITE_OK!=p->xCreate(argc-2, azArg, &pTokenizer) ){
    zErr = "error in xCreate()";
    goto finish;
  }
  pTokenizer->pModule = p;
  if( sqlite3Fts3OpenTokenizer(pTokenizer, 0, zInput, nInput, &pCsr) ){
    zErr = "error in xOpen()";
    goto finish;
  }

  while( SQLITE_OK==p->xNext(pCsr, &zToken, &nToken, &iStart, &iEnd, &iPos) ){
    Tcl_ListObjAppendElement(0, pRet, Tcl_NewIntObj(iPos));
    Tcl_ListObjAppendElement(0, pRet, Tcl_NewStringObj(zToken, nToken));
    zToken = &zInput[iStart];
    nToken = iEnd-iStart;
    Tcl_ListObjAppendElement(0, pRet, Tcl_NewStringObj(zToken, nToken));
  }

  if( SQLITE_OK!=p->xClose(pCsr) ){
    zErr = "error in xClose()";
    goto finish;
  }
  if( SQLITE_OK!=p->xDestroy(pTokenizer) ){
    zErr = "error in xDestroy()";
    goto finish;
  }

finish:
  if( zErr ){
    sqlite3_result_error(context, zErr, -1);
  }else{
    sqlite3_result_text(context, Tcl_GetString(pRet), -1, SQLITE_TRANSIENT);
  }
  Tcl_DecrRefCount(pRet);
}
예제 #2
0
/*
** This is the implementation of a scalar SQL function used to test the 
** expression parser. It should be called as follows:
**
**   fts3_exprtest(<tokenizer>, <expr>, <column 1>, ...);
**
** The first argument, <tokenizer>, is the name of the fts3 tokenizer used
** to parse the query expression (see README.tokenizers). The second argument
** is the query expression to parse. Each subsequent argument is the name
** of a column of the fts3 table that the query expression may refer to.
** For example:
**
**   SELECT fts3_exprtest('simple', 'Bill col2:Bloggs', 'col1', 'col2');
*/
static void fts3ExprTest(
  sqlite3_context *context,
  int argc,
  sqlite3_value **argv
){
  sqlite3_tokenizer_module const *pModule = 0;
  sqlite3_tokenizer *pTokenizer = 0;
  int rc;
  char **azCol = 0;
  const char *zExpr;
  int nExpr;
  int nCol;
  int ii;
  Fts3Expr *pExpr;
  char *zBuf = 0;
  sqlite3 *db = sqlite3_context_db_handle(context);

  if( argc<3 ){
    sqlite3_result_error(context, 
        "Usage: fts3_exprtest(tokenizer, expr, col1, ...", -1
    );
    return;
  }

  rc = queryTestTokenizer(db,
                          (const char *)sqlite3_value_text(argv[0]), &pModule);
  if( rc==SQLITE_NOMEM ){
    sqlite3_result_error_nomem(context);
    goto exprtest_out;
  }else if( !pModule ){
    sqlite3_result_error(context, "No such tokenizer module", -1);
    goto exprtest_out;
  }

  rc = pModule->xCreate(0, 0, &pTokenizer);
  assert( rc==SQLITE_NOMEM || rc==SQLITE_OK );
  if( rc==SQLITE_NOMEM ){
    sqlite3_result_error_nomem(context);
    goto exprtest_out;
  }
  pTokenizer->pModule = pModule;

  zExpr = (const char *)sqlite3_value_text(argv[1]);
  nExpr = sqlite3_value_bytes(argv[1]);
  nCol = argc-2;
  azCol = (char **)sqlite3_malloc(nCol*sizeof(char *));
  if( !azCol ){
    sqlite3_result_error_nomem(context);
    goto exprtest_out;
  }
  for(ii=0; ii<nCol; ii++){
    azCol[ii] = (char *)sqlite3_value_text(argv[ii+2]);
  }

  if( sqlite3_user_data(context) ){
    char *zDummy = 0;
    rc = sqlite3Fts3ExprParse(
        pTokenizer, 0, azCol, 0, nCol, nCol, zExpr, nExpr, &pExpr, &zDummy
    );
    assert( rc==SQLITE_OK || pExpr==0 );
    sqlite3_free(zDummy);
  }else{
    rc = fts3ExprParseUnbalanced(
        pTokenizer, 0, azCol, 0, nCol, nCol, zExpr, nExpr, &pExpr
    );
  }

  if( rc!=SQLITE_OK && rc!=SQLITE_NOMEM ){
    sqlite3Fts3ExprFree(pExpr);
    sqlite3_result_error(context, "Error parsing expression", -1);
  }else if( rc==SQLITE_NOMEM || !(zBuf = exprToString(pExpr, 0)) ){
    sqlite3_result_error_nomem(context);
  }else{
    sqlite3_result_text(context, zBuf, -1, SQLITE_TRANSIENT);
    sqlite3_free(zBuf);
  }

  sqlite3Fts3ExprFree(pExpr);

exprtest_out:
  if( pModule && pTokenizer ){
    rc = pModule->xDestroy(pTokenizer);
  }
  sqlite3_free(azCol);
}
static int
vspidx_filter (sqlite3_vtab_cursor * pCursor, int idxNum, const char *idxStr,
	       int argc, sqlite3_value ** argv)
{
/* setting up a cursor filter */
    char table_name[1024];
    char geom_column[1024];
    char idx_name[1024];
    char sql[4096];
    gaiaGeomCollPtr geom = NULL;
    int ok_table = 0;
    int ok_geom = 0;
    const unsigned char *blob;
    int size;
    int exists;
    int ret;
    sqlite3_stmt *stmt;
    float minx;
    float miny;
    float maxx;
    float maxy;
    double tic;
    double tic2;
    VirtualSpatialIndexCursorPtr cursor =
	(VirtualSpatialIndexCursorPtr) pCursor;
    VirtualSpatialIndexPtr spidx = (VirtualSpatialIndexPtr) cursor->pVtab;
    if (idxStr)
	idxStr = idxStr;	/* unused arg warning suppression */
    cursor->eof = 1;
    if (idxNum == 1 && argc == 3)
      {
	  /* retrieving the Table/Column/MBR params */
	  if (sqlite3_value_type (argv[0]) == SQLITE_TEXT)
	    {
		strcpy (table_name,
			(const char *) sqlite3_value_text (argv[0]));
		ok_table = 1;
	    }
	  if (sqlite3_value_type (argv[1]) == SQLITE_TEXT)
	    {
		strcpy (geom_column,
			(const char *) sqlite3_value_text (argv[1]));
		ok_geom = 1;
	    }
	  if (sqlite3_value_type (argv[2]) == SQLITE_BLOB)
	    {
		blob = sqlite3_value_blob (argv[2]);
		size = sqlite3_value_bytes (argv[2]);
		geom = gaiaFromSpatiaLiteBlobWkb (blob, size);
	    }
	  if (ok_table && ok_geom && geom)
	      ;
	  else
	    {
		/* invalid args */
		goto stop;
	    }
      }
    if (idxNum == 2 && argc == 2)
      {
	  /* retrieving the Table/MBR params */
	  if (sqlite3_value_type (argv[0]) == SQLITE_TEXT)
	    {
		strcpy (table_name,
			(const char *) sqlite3_value_text (argv[0]));
		ok_table = 1;
	    }
	  if (sqlite3_value_type (argv[1]) == SQLITE_BLOB)
	    {
		blob = sqlite3_value_blob (argv[1]);
		size = sqlite3_value_bytes (argv[1]);
		geom = gaiaFromSpatiaLiteBlobWkb (blob, size);
	    }
	  if (ok_table && geom)
	      ;
	  else
	    {
		/* invalid args */
		goto stop;
	    }
      }

/* checking if the corresponding R*Tree exists */
    if (ok_geom)
	exists = vspidx_check_rtree (spidx->db, table_name, geom_column);
    else
	exists = vspidx_find_rtree (spidx->db, table_name, geom_column);
    if (!exists)
	goto stop;

/* building the RTree query */
    sprintf (idx_name, "idx_%s_%s", table_name, geom_column);
    vspidx_double_quoted_sql (idx_name);
    sprintf (sql, "SELECT pkid FROM %s WHERE ", idx_name);
    strcat (sql, "xmin <= ? AND xmax >= ? AND ymin <= ? AND ymax >= ?");
    ret = sqlite3_prepare_v2 (spidx->db, sql, strlen (sql), &stmt, NULL);
    if (ret != SQLITE_OK)
	goto stop;
/* binding stmt params [MBR] */
    gaiaMbrGeometry (geom);

/* adjusting the MBR so to compensate for DOUBLE/FLOAT truncations */
    minx = (float)(geom->MinX);
    miny = (float)(geom->MinY);
    maxx = (float)(geom->MaxX);
    maxy = (float)(geom->MaxY);
    tic = fabs (geom->MinX - minx);
    tic2 = fabs (geom->MinY - miny);
    if (tic2 > tic)
	tic = tic2;
    tic2 = fabs (geom->MaxX - maxx);
    if (tic2 > tic)
	tic = tic2;
    tic2 = fabs (geom->MaxY - maxy);
    if (tic2 > tic)
	tic = tic2;
    tic *= 2.0;
    sqlite3_bind_double (stmt, 1, geom->MaxX + tic);
    sqlite3_bind_double (stmt, 2, geom->MinX - tic);
    sqlite3_bind_double (stmt, 3, geom->MaxY + tic);
    sqlite3_bind_double (stmt, 4, geom->MinY - tic);
    cursor->stmt = stmt;
    cursor->eof = 0;
/* fetching the first ResultSet's row */
    ret = sqlite3_step (cursor->stmt);
    if (ret == SQLITE_ROW)
	cursor->CurrentRowId = sqlite3_column_int64 (cursor->stmt, 0);
    else
	cursor->eof = 1;
  stop:
    return SQLITE_OK;
}
예제 #4
0
int sqlite3_column_bytes(sqlite3_stmt *pStmt, int i){
  int val = sqlite3_value_bytes( columnMem(pStmt,i) );
  columnMallocFailure(pStmt);
  return val;
}
예제 #5
0
static int do_callback(struct pdo_sqlite_fci *fc, zval *cb,
		int argc, sqlite3_value **argv, sqlite3_context *context,
		int is_agg)
{
	zval *zargs = NULL;
	zval retval;
	int i;
	int ret;
	int fake_argc;
	zend_reference *agg_context = NULL;

	if (is_agg) {
		is_agg = 2;
	}

	fake_argc = argc + is_agg;

	fc->fci.size = sizeof(fc->fci);
	ZVAL_COPY_VALUE(&fc->fci.function_name, cb);
	fc->fci.object = NULL;
	fc->fci.retval = &retval;
	fc->fci.param_count = fake_argc;

	/* build up the params */

	if (fake_argc) {
		zargs = safe_emalloc(fake_argc, sizeof(zval), 0);
	}

	if (is_agg) {
		agg_context = (zend_reference*)sqlite3_aggregate_context(context, sizeof(zend_reference));
		if (!agg_context) {
			ZVAL_NULL(&zargs[0]);
		} else {
			if (Z_ISUNDEF(agg_context->val)) {
				GC_REFCOUNT(agg_context) = 1;
				GC_TYPE_INFO(agg_context) = IS_REFERENCE;
				ZVAL_NULL(&agg_context->val);
			}
			ZVAL_REF(&zargs[0], agg_context);
		}
		ZVAL_LONG(&zargs[1], sqlite3_aggregate_count(context));
	}

	for (i = 0; i < argc; i++) {
		/* get the value */
		switch (sqlite3_value_type(argv[i])) {
			case SQLITE_INTEGER:
				ZVAL_LONG(&zargs[i + is_agg], sqlite3_value_int(argv[i]));
				break;

			case SQLITE_FLOAT:
				ZVAL_DOUBLE(&zargs[i + is_agg], sqlite3_value_double(argv[i]));
				break;

			case SQLITE_NULL:
				ZVAL_NULL(&zargs[i + is_agg]);
				break;

			case SQLITE_BLOB:
			case SQLITE3_TEXT:
			default:
				ZVAL_STRINGL(&zargs[i + is_agg], (char*)sqlite3_value_text(argv[i]), sqlite3_value_bytes(argv[i]));
				break;
		}
	}

	fc->fci.params = zargs;

	if ((ret = zend_call_function(&fc->fci, &fc->fcc)) == FAILURE) {
		php_error_docref(NULL, E_WARNING, "An error occurred while invoking the callback");
	}

	/* clean up the params */
	if (zargs) {
		for (i = is_agg; i < fake_argc; i++) {
			zval_ptr_dtor(&zargs[i]);
		}
		if (is_agg) {
			zval_ptr_dtor(&zargs[1]);
		}
		efree(zargs);
	}

	if (!is_agg || !argv) {
		/* only set the sqlite return value if we are a scalar function,
		 * or if we are finalizing an aggregate */
		if (!Z_ISUNDEF(retval)) {
			switch (Z_TYPE(retval)) {
				case IS_LONG:
					sqlite3_result_int(context, Z_LVAL(retval));
					break;

				case IS_NULL:
					sqlite3_result_null(context);
					break;

				case IS_DOUBLE:
					sqlite3_result_double(context, Z_DVAL(retval));
					break;

				default:
					convert_to_string_ex(&retval);
					sqlite3_result_text(context, Z_STRVAL(retval), Z_STRLEN(retval), SQLITE_TRANSIENT);
					break;
			}
		} else {
			sqlite3_result_error(context, "failed to invoke callback", 0);
		}

		if (agg_context) {
			zval_ptr_dtor(&agg_context->val);
		}
	} else {
		/* we're stepping in an aggregate; the return value goes into
		 * the context */
		if (agg_context) {
			zval_ptr_dtor(&agg_context->val);
		}
		if (!Z_ISUNDEF(retval)) {
			ZVAL_COPY_VALUE(&agg_context->val, &retval);
			ZVAL_UNDEF(&retval);
		} else {
			ZVAL_UNDEF(&agg_context->val);
		}
	}

	if (!Z_ISUNDEF(retval)) {
		zval_ptr_dtor(&retval);
	}

	return ret;
}
예제 #6
0
/*
** An SQL user-function registered to do the work of an ATTACH statement. The
** three arguments to the function come directly from an attach statement:
**
**     ATTACH DATABASE x AS y KEY z
**
**     SELECT sqlite_attach(x, y, z)
**
** If the optional "KEY z" syntax is omitted, an SQL NULL is passed as the
** third argument.
*/
static void attachFunc(
  sqlite3_context *context,
  int NotUsed,
  sqlite3_value **argv
){
  int i;
  int rc = 0;
  sqlite3 *db = sqlite3_context_db_handle(context);
  const char *zName;
  const char *zFile;
  char *zPath = 0;
  char *zErr = 0;
  unsigned int flags;
  Db *aNew;
  char *zErrDyn = 0;
  sqlite3_vfs *pVfs;

  UNUSED_PARAMETER(NotUsed);

  zFile = (const char *)sqlite3_value_text(argv[0]);
  zName = (const char *)sqlite3_value_text(argv[1]);
  if( zFile==0 ) zFile = "";
  if( zName==0 ) zName = "";

  /* Check for the following errors:
  **
  **     * Too many attached databases,
  **     * Transaction currently open
  **     * Specified database name already being used.
  */
  if( db->nDb>=db->aLimit[SQLITE_LIMIT_ATTACHED]+2 ){
    zErrDyn = sqlite3MPrintf(db, "too many attached databases - max %d", 
      db->aLimit[SQLITE_LIMIT_ATTACHED]
    );
    goto attach_error;
  }
  if( !db->autoCommit ){
    zErrDyn = sqlite3MPrintf(db, "cannot ATTACH database within transaction");
    goto attach_error;
  }
  for(i=0; i<db->nDb; i++){
    char *z = db->aDb[i].zName;
    assert( z && zName );
    if( sqlite3StrICmp(z, zName)==0 ){
      zErrDyn = sqlite3MPrintf(db, "database %s is already in use", zName);
      goto attach_error;
    }
  }

  /* Allocate the new entry in the db->aDb[] array and initialize the schema
  ** hash tables.
  */
  if( db->aDb==db->aDbStatic ){
    aNew = sqlite3DbMallocRaw(db, sizeof(db->aDb[0])*3 );
    if( aNew==0 ) return;
    memcpy(aNew, db->aDb, sizeof(db->aDb[0])*2);
  }else{
    aNew = sqlite3DbRealloc(db, db->aDb, sizeof(db->aDb[0])*(db->nDb+1) );
    if( aNew==0 ) return;
  }
  db->aDb = aNew;
  aNew = &db->aDb[db->nDb];
  memset(aNew, 0, sizeof(*aNew));

  /* Open the database file. If the btree is successfully opened, use
  ** it to obtain the database schema. At this point the schema may
  ** or may not be initialized.
  */
  flags = db->openFlags;
  rc = sqlite3ParseUri(db->pVfs->zName, zFile, &flags, &pVfs, &zPath, &zErr);
  if( rc!=SQLITE_OK ){
    if( rc==SQLITE_NOMEM ) db->mallocFailed = 1;
    sqlite3_result_error(context, zErr, -1);
    sqlite3_free(zErr);
    return;
  }
  assert( pVfs );
  flags |= SQLITE_OPEN_MAIN_DB;
  rc = sqlite3BtreeOpen(pVfs, zPath, db, &aNew->pBt, 0, flags);
  sqlite3_free( zPath );
  db->nDb++;
  if( rc==SQLITE_CONSTRAINT ){
    rc = SQLITE_ERROR;
    zErrDyn = sqlite3MPrintf(db, "database is already attached");
  }else if( rc==SQLITE_OK ){
    Pager *pPager;
    aNew->pSchema = sqlite3SchemaGet(db, aNew->pBt);
    if( !aNew->pSchema ){
      rc = SQLITE_NOMEM;
    }else if( aNew->pSchema->file_format && aNew->pSchema->enc!=ENC(db) ){
      zErrDyn = sqlite3MPrintf(db, 
        "attached databases must use the same text encoding as main database");
      rc = SQLITE_ERROR;
    }
    pPager = sqlite3BtreePager(aNew->pBt);
    sqlite3PagerLockingMode(pPager, db->dfltLockMode);
    sqlite3BtreeSecureDelete(aNew->pBt,
                             sqlite3BtreeSecureDelete(db->aDb[0].pBt,-1) );
#ifndef SQLITE_OMIT_PAGER_PRAGMAS
    sqlite3BtreeSetPagerFlags(aNew->pBt, 3 | (db->flags & PAGER_FLAGS_MASK));
#endif
  }
  aNew->safety_level = 3;
  aNew->zName = sqlite3DbStrDup(db, zName);
  if( rc==SQLITE_OK && aNew->zName==0 ){
    rc = SQLITE_NOMEM;
  }


#ifdef SQLITE_HAS_CODEC
  if( rc==SQLITE_OK ){
    extern int sqlite3CodecAttach(sqlite3*, int, const void*, int);
    extern void sqlite3CodecGetKey(sqlite3*, int, void**, int*);
    int nKey;
    char *zKey;
    int t = sqlite3_value_type(argv[2]);
    switch( t ){
      case SQLITE_INTEGER:
      case SQLITE_FLOAT:
        zErrDyn = sqlite3DbStrDup(db, "Invalid key value");
        rc = SQLITE_ERROR;
        break;
        
      case SQLITE_TEXT:
      case SQLITE_BLOB:
        nKey = sqlite3_value_bytes(argv[2]);
        zKey = (char *)sqlite3_value_blob(argv[2]);
        rc = sqlite3CodecAttach(db, db->nDb-1, zKey, nKey);
        break;

      case SQLITE_NULL:
        /* No key specified.  Use the key from the main database */
        sqlite3CodecGetKey(db, 0, (void**)&zKey, &nKey);
        if( nKey>0 || sqlite3BtreeGetReserve(db->aDb[0].pBt)>0 ){
          rc = sqlite3CodecAttach(db, db->nDb-1, zKey, nKey);
        }
        break;
    }
  }
#endif

  /* If the file was opened successfully, read the schema for the new database.
  ** If this fails, or if opening the file failed, then close the file and 
  ** remove the entry from the db->aDb[] array. i.e. put everything back the way
  ** we found it.
  */
  if( rc==SQLITE_OK ){
    sqlite3BtreeEnterAll(db);
    rc = sqlite3Init(db, &zErrDyn);
    sqlite3BtreeLeaveAll(db);
  }
#ifdef SQLITE_USER_AUTHENTICATION
  if( rc==SQLITE_OK ){
    u8 newAuth = 0;
    rc = sqlite3UserAuthCheckLogin(db, zName, &newAuth);
    if( newAuth<db->auth.authLevel ){
      rc = SQLITE_AUTH_USER;
    }
  }
#endif
  if( rc ){
    int iDb = db->nDb - 1;
    assert( iDb>=2 );
    if( db->aDb[iDb].pBt ){
      sqlite3BtreeClose(db->aDb[iDb].pBt);
      db->aDb[iDb].pBt = 0;
      db->aDb[iDb].pSchema = 0;
    }
    sqlite3ResetAllSchemasOfConnection(db);
    db->nDb = iDb;
    if( rc==SQLITE_NOMEM || rc==SQLITE_IOERR_NOMEM ){
      db->mallocFailed = 1;
      sqlite3DbFree(db, zErrDyn);
      zErrDyn = sqlite3MPrintf(db, "out of memory");
    }else if( zErrDyn==0 ){
      zErrDyn = sqlite3MPrintf(db, "unable to open database: %s", zFile);
    }
    goto attach_error;
  }
  
  return;

attach_error:
  /* Return an error if we get here */
  if( zErrDyn ){
    sqlite3_result_error(context, zErrDyn, -1);
    sqlite3DbFree(db, zErrDyn);
  }
  if( rc ) sqlite3_result_error_code(context, rc);
}
예제 #7
0
/*
** An SQL user-function registered to do the work of an ATTACH statement. The
** three arguments to the function come directly from an attach statement:
**
**     ATTACH DATABASE x AS y KEY z
**
**     SELECT sqlite_attach(x, y, z)
**
** If the optional "KEY z" syntax is omitted, an SQL NULL is passed as the
** third argument.
*/
static void attachFunc(
  sqlite3_context *context,
  int argc,
  sqlite3_value **argv
){
  int i;
  int rc = 0;
  sqlite3 *db = sqlite3_user_data(context);
  const char *zName;
  const char *zFile;
  Db *aNew;
  char zErr[128];
  char *zErrDyn = 0;

  zFile = (const char *)sqlite3_value_text(argv[0]);
  zName = (const char *)sqlite3_value_text(argv[1]);
  if( zFile==0 ) zFile = "";
  if( zName==0 ) zName = "";

  /* Check for the following errors:
  **
  **     * Too many attached databases,
  **     * Transaction currently open
  **     * Specified database name already being used.
  */
  if( db->nDb>=MAX_ATTACHED+2 ){
    sqlite3_snprintf(
      sizeof(zErr), zErr, "too many attached databases - max %d", MAX_ATTACHED
    );
    goto attach_error;
  }
  if( !db->autoCommit ){
    strcpy(zErr, "cannot ATTACH database within transaction");
    goto attach_error;
  }
  for(i=0; i<db->nDb; i++){
    char *z = db->aDb[i].zName;
    if( z && zName && sqlite3StrICmp(z, zName)==0 ){
      sqlite3_snprintf(sizeof(zErr), zErr, "database %s is already in use", zName);
      goto attach_error;
    }
  }

  /* Allocate the new entry in the db->aDb[] array and initialise the schema
  ** hash tables.
  */
  if( db->aDb==db->aDbStatic ){
    aNew = sqliteMalloc( sizeof(db->aDb[0])*3 );
    if( aNew==0 ){
      return;
    }
    memcpy(aNew, db->aDb, sizeof(db->aDb[0])*2);
  }else{
    aNew = sqliteRealloc(db->aDb, sizeof(db->aDb[0])*(db->nDb+1) );
    if( aNew==0 ){
      return;
    } 
  }
  db->aDb = aNew;
  aNew = &db->aDb[db->nDb++];
  memset(aNew, 0, sizeof(*aNew));

  /* Open the database file. If the btree is successfully opened, use
  ** it to obtain the database schema. At this point the schema may
  ** or may not be initialised.
  */
  rc = sqlite3BtreeFactory(db, zFile, 0, MAX_PAGES, &aNew->pBt);
  if( rc==SQLITE_OK ){
    aNew->pSchema = sqlite3SchemaGet(aNew->pBt);
    if( !aNew->pSchema ){
      rc = SQLITE_NOMEM;
    }else if( aNew->pSchema->file_format && aNew->pSchema->enc!=ENC(db) ){
      strcpy(zErr, 
        "attached databases must use the same text encoding as main database");
      goto attach_error;
    }
  }
  aNew->zName = sqliteStrDup(zName);
  aNew->safety_level = 3;

#if SQLITE_HAS_CODEC
  {
    extern int sqlite3CodecAttach(sqlite3*, int, void*, int);
    extern void sqlite3CodecGetKey(sqlite3*, int, void**, int*);
    int nKey;
    char *zKey;
    int t = sqlite3_value_type(argv[2]);
    switch( t ){
      case SQLITE_INTEGER:
      case SQLITE_FLOAT:
        zErrDyn = sqliteStrDup("Invalid key value");
        rc = SQLITE_ERROR;
        break;
        
      case SQLITE_TEXT:
      case SQLITE_BLOB:
        nKey = sqlite3_value_bytes(argv[2]);
        zKey = (char *)sqlite3_value_blob(argv[2]);
        sqlite3CodecAttach(db, db->nDb-1, zKey, nKey);
        break;

      case SQLITE_NULL:
        /* No key specified.  Use the key from the main database */
        sqlite3CodecGetKey(db, 0, (void**)&zKey, &nKey);
        sqlite3CodecAttach(db, db->nDb-1, zKey, nKey);
        break;
    }
  }
#endif

  /* If the file was opened successfully, read the schema for the new database.
  ** If this fails, or if opening the file failed, then close the file and 
  ** remove the entry from the db->aDb[] array. i.e. put everything back the way
  ** we found it.
  */
  if( rc==SQLITE_OK ){
    sqlite3SafetyOn(db);
    rc = sqlite3Init(db, &zErrDyn);
    sqlite3SafetyOff(db);
  }
  if( rc ){
    int iDb = db->nDb - 1;
    assert( iDb>=2 );
    if( db->aDb[iDb].pBt ){
      sqlite3BtreeClose(db->aDb[iDb].pBt);
      db->aDb[iDb].pBt = 0;
      db->aDb[iDb].pSchema = 0;
    }
    sqlite3ResetInternalSchema(db, 0);
    db->nDb = iDb;
    if( rc==SQLITE_NOMEM ){
      if( !sqlite3MallocFailed() ) sqlite3FailedMalloc();
      sqlite3_snprintf(sizeof(zErr),zErr, "out of memory");
    }else{
      sqlite3_snprintf(sizeof(zErr),zErr, "unable to open database: %s", zFile);
    }
    goto attach_error;
  }
  
  return;

attach_error:
  /* Return an error if we get here */
  if( zErrDyn ){
    sqlite3_result_error(context, zErrDyn, -1);
    sqliteFree(zErrDyn);
  }else{
    zErr[sizeof(zErr)-1] = 0;
    sqlite3_result_error(context, zErr, -1);
  }
}