sqlite3.c

/*
   +----------------------------------------------------------------------+
   | Copyright (c) The PHP Group                                          |
   +----------------------------------------------------------------------+
   | This source file is subject to version 3.01 of the PHP license,      |
   | that is bundled with this package in the file LICENSE, and is        |
   | available through the world-wide-web at the following url:           |
   | https://www.php.net/license/3_01.txt                                 |
   | If you did not receive a copy of the PHP license and are unable to   |
   | obtain it through the world-wide-web, please send a note to          |
   | license@php.net so we can mail you a copy immediately.               |
   +----------------------------------------------------------------------+
   | Authors: Scott MacVicar <scottmac@php.net>                           |
   +----------------------------------------------------------------------+
*/

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include "php.h"
#include "php_ini.h"
#include "ext/standard/info.h"
#include "php_sqlite3.h"
#include "php_sqlite3_structs.h"
#include "main/SAPI.h"

#include <sqlite3.h>

#include "zend_exceptions.h"
#include "SAPI.h"
#include "sqlite3_arginfo.h"

ZEND_DECLARE_MODULE_GLOBALS(sqlite3)

static PHP_GINIT_FUNCTION(sqlite3);
static int php_sqlite3_authorizer(void *autharg, int action, const char *arg1, const char *arg2, const char *arg3, const char *arg4);
static void sqlite3_param_dtor(zval *data);
static int php_sqlite3_compare_stmt_zval_free(php_sqlite3_free_list **free_list, zval *statement);

/* {{{ Error Handler */
static void php_sqlite3_error(php_sqlite3_db_object *db_obj, char *format, ...)
{
	va_list arg;
	char 	*message;

	va_start(arg, format);
	vspprintf(&message, 0, format, arg);
	va_end(arg);

	if (db_obj && db_obj->exception) {
		zend_throw_exception(zend_ce_exception, message, 0);
	} else {
		php_error_docref(NULL, E_WARNING, "%s", message);
	}

	if (message) {
		efree(message);
	}
}
/* }}} */

#define SQLITE3_CHECK_INITIALIZED(db_obj, member, class_name) \
	if (!(db_obj) || !(member)) { \
		zend_throw_error(NULL, "The " #class_name " object has not been correctly initialised or is already closed"); \
		RETURN_THROWS(); \
	}

#define SQLITE3_CHECK_INITIALIZED_STMT(member, class_name) \
	if (!(member)) { \
		zend_throw_error(NULL, "The " #class_name " object has not been correctly initialised or is already closed"); \
		RETURN_THROWS(); \
	}

/* {{{ PHP_INI */
PHP_INI_BEGIN()
	STD_PHP_INI_ENTRY("sqlite3.extension_dir",  NULL, PHP_INI_SYSTEM, OnUpdateString, extension_dir, zend_sqlite3_globals, sqlite3_globals)
#if SQLITE_VERSION_NUMBER >= 3026000
	STD_PHP_INI_BOOLEAN("sqlite3.defensive",  "1", PHP_INI_USER, OnUpdateBool, dbconfig_defensive, zend_sqlite3_globals, sqlite3_globals)
#endif
PHP_INI_END()
/* }}} */

/* Handlers */
static zend_object_handlers sqlite3_object_handlers;
static zend_object_handlers sqlite3_stmt_object_handlers;
static zend_object_handlers sqlite3_result_object_handlers;

/* Class entries */
zend_class_entry *php_sqlite3_sc_entry;
zend_class_entry *php_sqlite3_stmt_entry;
zend_class_entry *php_sqlite3_result_entry;

/* {{{ Opens a SQLite 3 Database, if the build includes encryption then it will attempt to use the key. */
PHP_METHOD(SQLite3, open)
{
	php_sqlite3_db_object *db_obj;
	zval *object = ZEND_THIS;
	char *filename, *encryption_key, *fullpath;
	size_t filename_len, encryption_key_len = 0;
	zend_long flags = SQLITE_OPEN_READWRITE | SQLITE_OPEN_CREATE;
	int rc;

	db_obj = Z_SQLITE3_DB_P(object);

	if (FAILURE == zend_parse_parameters(ZEND_NUM_ARGS(), "p|ls", &filename, &filename_len, &flags, &encryption_key, &encryption_key_len)) {
		RETURN_THROWS();
	}

	if (db_obj->initialised) {
		zend_throw_exception(zend_ce_exception, "Already initialised DB Object", 0);
		RETURN_THROWS();
	}

	if (filename_len != 0 && (filename_len != sizeof(":memory:")-1 ||
			memcmp(filename, ":memory:", sizeof(":memory:")-1) != 0)) {
		if (!(fullpath = expand_filepath(filename, NULL))) {
			zend_throw_exception(zend_ce_exception, "Unable to expand filepath", 0);
			RETURN_THROWS();
		}

		if (php_check_open_basedir(fullpath)) {
			zend_throw_exception_ex(zend_ce_exception, 0, "open_basedir prohibits opening %s", fullpath);
			efree(fullpath);
			RETURN_THROWS();
		}
	} else {
		/* filename equals "" or ":memory:" */
		fullpath = filename;
	}

	rc = sqlite3_open_v2(fullpath, &(db_obj->db), flags, NULL);
	if (rc != SQLITE_OK) {
		zend_throw_exception_ex(zend_ce_exception, 0, "Unable to open database: %s",
#ifdef HAVE_SQLITE3_ERRSTR
				db_obj->db ? sqlite3_errmsg(db_obj->db) : sqlite3_errstr(rc));
#else
				db_obj->db ? sqlite3_errmsg(db_obj->db) : "");
#endif
		sqlite3_close(db_obj->db);
		if (fullpath != filename) {
			efree(fullpath);
		}
		return;
	}

#ifdef SQLITE_HAS_CODEC
	if (encryption_key_len > 0) {
		if (sqlite3_key(db_obj->db, encryption_key, encryption_key_len) != SQLITE_OK) {
			zend_throw_exception_ex(zend_ce_exception, 0, "Unable to open database: %s", sqlite3_errmsg(db_obj->db));
			sqlite3_close(db_obj->db);
			RETURN_THROWS();
		}
	}
#endif

	db_obj->initialised = 1;
	db_obj->authorizer_fci = empty_fcall_info;
	db_obj->authorizer_fcc = empty_fcall_info_cache;

	sqlite3_set_authorizer(db_obj->db, php_sqlite3_authorizer, db_obj);

#if SQLITE_VERSION_NUMBER >= 3026000
	if (SQLITE3G(dbconfig_defensive)) {
		sqlite3_db_config(db_obj->db, SQLITE_DBCONFIG_DEFENSIVE, 1, NULL);
	}
#endif

	if (fullpath != filename) {
		efree(fullpath);
	}
}
/* }}} */

/* {{{ Close a SQLite 3 Database. */
PHP_METHOD(SQLite3, close)
{
	php_sqlite3_db_object *db_obj;
	zval *object = ZEND_THIS;
	int errcode;
	db_obj = Z_SQLITE3_DB_P(object);

	if (zend_parse_parameters_none() == FAILURE) {
		RETURN_THROWS();
	}

	if (db_obj->initialised) {
		zend_llist_clean(&(db_obj->free_list));
		if(db_obj->db) {
			errcode = sqlite3_close(db_obj->db);
			if (errcode != SQLITE_OK) {
				php_sqlite3_error(db_obj, "Unable to close database: %d, %s", errcode, sqlite3_errmsg(db_obj->db));
				RETURN_FALSE;
			}
		}
		db_obj->initialised = 0;
	}

	RETURN_TRUE;
}
/* }}} */

/* {{{ Executes a result-less query against a given database. */
PHP_METHOD(SQLite3, exec)
{
	php_sqlite3_db_object *db_obj;
	zval *object = ZEND_THIS;
	zend_string *sql;
	char *errtext = NULL;
	db_obj = Z_SQLITE3_DB_P(object);

	if (FAILURE == zend_parse_parameters(ZEND_NUM_ARGS(), "S", &sql)) {
		RETURN_THROWS();
	}

	SQLITE3_CHECK_INITIALIZED(db_obj, db_obj->initialised, SQLite3)

	if (sqlite3_exec(db_obj->db, ZSTR_VAL(sql), NULL, NULL, &errtext) != SQLITE_OK) {
		php_sqlite3_error(db_obj, "%s", errtext);
		sqlite3_free(errtext);
		RETURN_FALSE;
	}

	RETURN_TRUE;
}
/* }}} */

/* {{{ Returns the SQLite3 Library version as a string constant and as a number. */
PHP_METHOD(SQLite3, version)
{
	if (zend_parse_parameters_none() == FAILURE) {
		RETURN_THROWS();
	}

	array_init(return_value);

	add_assoc_string(return_value, "versionString", (char*)sqlite3_libversion());
	add_assoc_long(return_value, "versionNumber", sqlite3_libversion_number());

	return;
}
/* }}} */

/* {{{ Returns the rowid of the most recent INSERT into the database from the database connection. */
PHP_METHOD(SQLite3, lastInsertRowID)
{
	php_sqlite3_db_object *db_obj;
	zval *object = ZEND_THIS;
	db_obj = Z_SQLITE3_DB_P(object);

	if (zend_parse_parameters_none() == FAILURE) {
		RETURN_THROWS();
	}

	SQLITE3_CHECK_INITIALIZED(db_obj, db_obj->initialised, SQLite3)

	RETURN_LONG((zend_long) sqlite3_last_insert_rowid(db_obj->db));
}
/* }}} */

/* {{{ Returns the numeric result code of the most recent failed sqlite API call for the database connection. */
PHP_METHOD(SQLite3, lastErrorCode)
{
	php_sqlite3_db_object *db_obj;
	zval *object = ZEND_THIS;
	db_obj = Z_SQLITE3_DB_P(object);

	if (zend_parse_parameters_none() == FAILURE) {
		RETURN_THROWS();
	}

	SQLITE3_CHECK_INITIALIZED(db_obj, db_obj->db, SQLite3)

	if (db_obj->initialised) {
		RETURN_LONG(sqlite3_errcode(db_obj->db));
	} else {
		RETURN_LONG(0);
	}
}
/* }}} */

/* {{{ Returns the numeric extended result code of the most recent failed sqlite API call for the database connection. */
PHP_METHOD(SQLite3, lastExtendedErrorCode)
{
	php_sqlite3_db_object *db_obj;
	zval *object = ZEND_THIS;
	db_obj = Z_SQLITE3_DB_P(object);

	if (zend_parse_parameters_none() == FAILURE) {
		RETURN_THROWS();
	}

	SQLITE3_CHECK_INITIALIZED(db_obj, db_obj->db, SQLite3)

	if (db_obj->initialised) {
		RETURN_LONG(sqlite3_extended_errcode(db_obj->db));
	} else {
		RETURN_LONG(0);
	}
}
/* }}} */

/* {{{ Turns on or off the extended result codes feature of SQLite. */
PHP_METHOD(SQLite3, enableExtendedResultCodes)
{
	php_sqlite3_db_object *db_obj;
	zval *object = ZEND_THIS;
	bool enable = 1;
	db_obj = Z_SQLITE3_DB_P(object);
	int ret;

	if (zend_parse_parameters(ZEND_NUM_ARGS(), "|b", &enable) == FAILURE) {
		RETURN_THROWS();
	}

	SQLITE3_CHECK_INITIALIZED(db_obj, db_obj->db, SQLite3)

	if (db_obj->initialised) {
		ret = sqlite3_extended_result_codes(db_obj->db, enable ? 1 : 0);
		if (ret == SQLITE_OK)
		{
			RETURN_TRUE;
		}
	}

	RETURN_FALSE;
}
/* }}} */

/* {{{ Returns english text describing the most recent failed sqlite API call for the database connection. */
PHP_METHOD(SQLite3, lastErrorMsg)
{
	php_sqlite3_db_object *db_obj;
	zval *object = ZEND_THIS;
	db_obj = Z_SQLITE3_DB_P(object);

	if (zend_parse_parameters_none() == FAILURE) {
		RETURN_THROWS();
	}

	SQLITE3_CHECK_INITIALIZED(db_obj, db_obj->db, SQLite3)

	if (db_obj->initialised) {
		RETURN_STRING((char *)sqlite3_errmsg(db_obj->db));
	} else {
		RETURN_EMPTY_STRING();
	}
}
/* }}} */

/* {{{ Sets a busy handler that will sleep until database is not locked or timeout is reached. Passing a value less than or equal to zero turns off all busy handlers. */
PHP_METHOD(SQLite3, busyTimeout)
{
	php_sqlite3_db_object *db_obj;
	zval *object = ZEND_THIS;
	zend_long ms;
#ifdef SQLITE_ENABLE_API_ARMOR
	int return_code;
#endif
	db_obj = Z_SQLITE3_DB_P(object);

	if (FAILURE == zend_parse_parameters(ZEND_NUM_ARGS(), "l", &ms)) {
		RETURN_THROWS();
	}

	SQLITE3_CHECK_INITIALIZED(db_obj, db_obj->initialised, SQLite3)

#ifdef SQLITE_ENABLE_API_ARMOR
	return_code = sqlite3_busy_timeout(db_obj->db, ms);
	if (return_code != SQLITE_OK) {
		php_sqlite3_error(db_obj, "Unable to set busy timeout: %d, %s", return_code, sqlite3_errmsg(db_obj->db));
		RETURN_FALSE;
	}
#else
	php_ignore_value(sqlite3_busy_timeout(db_obj->db, ms));
#endif

	RETURN_TRUE;
}
/* }}} */


#ifndef SQLITE_OMIT_LOAD_EXTENSION
/* {{{ Attempts to load an SQLite extension library. */
PHP_METHOD(SQLite3, loadExtension)
{
	php_sqlite3_db_object *db_obj;
	zval *object = ZEND_THIS;
	char *extension, *lib_path, *extension_dir, *errtext = NULL;
	char fullpath[MAXPATHLEN];
	size_t extension_len, extension_dir_len;
	db_obj = Z_SQLITE3_DB_P(object);

	if (FAILURE == zend_parse_parameters(ZEND_NUM_ARGS(), "s", &extension, &extension_len)) {
		RETURN_THROWS();
	}

	SQLITE3_CHECK_INITIALIZED(db_obj, db_obj->initialised, SQLite3)

#ifdef ZTS
	if ((strncmp(sapi_module.name, "cgi", 3) != 0) &&
		(strcmp(sapi_module.name, "cli") != 0) &&
		(strncmp(sapi_module.name, "embed", 5) != 0)
	) {		php_sqlite3_error(db_obj, "Not supported in multithreaded Web servers");
		RETURN_FALSE;
	}
#endif

	if (!SQLITE3G(extension_dir)) {
		php_sqlite3_error(db_obj, "SQLite Extension are disabled");
		RETURN_FALSE;
	}

	if (extension_len == 0) {
		php_sqlite3_error(db_obj, "Empty string as an extension");
		RETURN_FALSE;
	}

	extension_dir = SQLITE3G(extension_dir);
	extension_dir_len = strlen(SQLITE3G(extension_dir));

	if (IS_SLASH(extension_dir[extension_dir_len-1])) {
		spprintf(&lib_path, 0, "%s%s", extension_dir, extension);
	} else {
		spprintf(&lib_path, 0, "%s%c%s", extension_dir, DEFAULT_SLASH, extension);
	}

	if (!VCWD_REALPATH(lib_path, fullpath)) {
		php_sqlite3_error(db_obj, "Unable to load extension at '%s'", lib_path);
		efree(lib_path);
		RETURN_FALSE;
	}

	efree(lib_path);

	if (strncmp(fullpath, extension_dir, extension_dir_len) != 0) {
		php_sqlite3_error(db_obj, "Unable to open extensions outside the defined directory");
		RETURN_FALSE;
	}

	/* Extension loading should only be enabled for when we attempt to load */
	sqlite3_enable_load_extension(db_obj->db, 1);
	if (sqlite3_load_extension(db_obj->db, fullpath, 0, &errtext) != SQLITE_OK) {
		php_sqlite3_error(db_obj, "%s", errtext);
		sqlite3_free(errtext);
		sqlite3_enable_load_extension(db_obj->db, 0);
		RETURN_FALSE;
	}
	sqlite3_enable_load_extension(db_obj->db, 0);

	RETURN_TRUE;
}
/* }}} */
#endif

/* {{{ Returns the number of database rows that were changed (or inserted or deleted) by the most recent SQL statement. */
PHP_METHOD(SQLite3, changes)
{
	php_sqlite3_db_object *db_obj;
	zval *object = ZEND_THIS;
	db_obj = Z_SQLITE3_DB_P(object);

	if (zend_parse_parameters_none() == FAILURE) {
		RETURN_THROWS();
	}

	SQLITE3_CHECK_INITIALIZED(db_obj, db_obj->initialised, SQLite3)

	RETURN_LONG(sqlite3_changes(db_obj->db));
}
/* }}} */

/* {{{ Returns a string that has been properly escaped. */
PHP_METHOD(SQLite3, escapeString)
{
	zend_string *sql;
	char *ret;

	if (FAILURE == zend_parse_parameters(ZEND_NUM_ARGS(), "S", &sql)) {
		RETURN_THROWS();
	}

	if (ZSTR_LEN(sql)) {
		ret = sqlite3_mprintf("%q", ZSTR_VAL(sql));
		if (ret) {
			RETVAL_STRING(ret);
			sqlite3_free(ret);
		}
	} else {
		RETURN_EMPTY_STRING();
	}
}
/* }}} */

/* {{{ Returns a prepared SQL statement for execution. */
PHP_METHOD(SQLite3, prepare)
{
	php_sqlite3_db_object *db_obj;
	php_sqlite3_stmt *stmt_obj;
	zval *object = ZEND_THIS;
	zend_string *sql;
	int errcode;
	php_sqlite3_free_list *free_item;

	db_obj = Z_SQLITE3_DB_P(object);

	if (FAILURE == zend_parse_parameters(ZEND_NUM_ARGS(), "S", &sql)) {
		RETURN_THROWS();
	}

	SQLITE3_CHECK_INITIALIZED(db_obj, db_obj->initialised, SQLite3)

	if (!ZSTR_LEN(sql)) {
		RETURN_FALSE;
	}

	object_init_ex(return_value, php_sqlite3_stmt_entry);
	stmt_obj = Z_SQLITE3_STMT_P(return_value);
	stmt_obj->db_obj = db_obj;
	ZVAL_OBJ_COPY(&stmt_obj->db_obj_zval, Z_OBJ_P(object));

	errcode = sqlite3_prepare_v2(db_obj->db, ZSTR_VAL(sql), ZSTR_LEN(sql), &(stmt_obj->stmt), NULL);
	if (errcode != SQLITE_OK) {
		php_sqlite3_error(db_obj, "Unable to prepare statement: %d, %s", errcode, sqlite3_errmsg(db_obj->db));
		zval_ptr_dtor(return_value);
		RETURN_FALSE;
	}

	stmt_obj->initialised = 1;

	free_item = emalloc(sizeof(php_sqlite3_free_list));
	free_item->stmt_obj = stmt_obj;
	ZVAL_OBJ(&free_item->stmt_obj_zval, Z_OBJ_P(return_value));

	zend_llist_add_element(&(db_obj->free_list), &free_item);
}
/* }}} */

/* {{{ Returns true or false, for queries that return data it will return a SQLite3Result object. */
PHP_METHOD(SQLite3, query)
{
	php_sqlite3_db_object *db_obj;
	php_sqlite3_result *result;
	php_sqlite3_stmt *stmt_obj;
	zval *object = ZEND_THIS;
	zval stmt;
	zend_string *sql;
	char *errtext = NULL;
	int return_code;
	db_obj = Z_SQLITE3_DB_P(object);

	if (FAILURE == zend_parse_parameters(ZEND_NUM_ARGS(), "S", &sql)) {
		RETURN_THROWS();
	}

	SQLITE3_CHECK_INITIALIZED(db_obj, db_obj->initialised, SQLite3)

	if (!ZSTR_LEN(sql)) {
		RETURN_FALSE;
	}

	/* If there was no return value then just execute the query */
	if (!USED_RET()) {
		if (sqlite3_exec(db_obj->db, ZSTR_VAL(sql), NULL, NULL, &errtext) != SQLITE_OK) {
			php_sqlite3_error(db_obj, "%s", errtext);
			sqlite3_free(errtext);
		}
		RETURN_FALSE;
	}

	object_init_ex(&stmt, php_sqlite3_stmt_entry);
	stmt_obj = Z_SQLITE3_STMT_P(&stmt);
	stmt_obj->db_obj = db_obj;
	ZVAL_OBJ_COPY(&stmt_obj->db_obj_zval, Z_OBJ_P(object));

	return_code = sqlite3_prepare_v2(db_obj->db, ZSTR_VAL(sql), ZSTR_LEN(sql), &(stmt_obj->stmt), NULL);
	if (return_code != SQLITE_OK) {
		php_sqlite3_error(db_obj, "Unable to prepare statement: %d, %s", return_code, sqlite3_errmsg(db_obj->db));
		zval_ptr_dtor(&stmt);
		RETURN_FALSE;
	}

	stmt_obj->initialised = 1;

	object_init_ex(return_value, php_sqlite3_result_entry);
	result = Z_SQLITE3_RESULT_P(return_value);
	result->db_obj = db_obj;
	result->stmt_obj = stmt_obj;
	result->column_names = NULL;
	result->column_count = -1;
	ZVAL_OBJ(&result->stmt_obj_zval, Z_OBJ(stmt));

	return_code = sqlite3_step(result->stmt_obj->stmt);

	switch (return_code) {
		case SQLITE_ROW: /* Valid Row */
		case SQLITE_DONE: /* Valid but no results */
		{
			php_sqlite3_free_list *free_item;
			free_item = emalloc(sizeof(php_sqlite3_free_list));
			free_item->stmt_obj = stmt_obj;
			free_item->stmt_obj_zval = stmt;
			zend_llist_add_element(&(db_obj->free_list), &free_item);
			sqlite3_reset(result->stmt_obj->stmt);
			break;
		}
		default:
			if (!EG(exception)) {
				php_sqlite3_error(db_obj, "Unable to execute statement: %s", sqlite3_errmsg(db_obj->db));
			}
			sqlite3_finalize(stmt_obj->stmt);
			stmt_obj->initialised = 0;
			zval_ptr_dtor(return_value);
			RETURN_FALSE;
	}
}
/* }}} */

static void sqlite_value_to_zval(sqlite3_stmt *stmt, int column, zval *data) /* {{{ */
{
	sqlite3_int64 val;

	switch (sqlite3_column_type(stmt, column)) {
		case SQLITE_INTEGER:
			val = sqlite3_column_int64(stmt, column);
#if LONG_MAX <= 2147483647
			if (val > ZEND_LONG_MAX || val < ZEND_LONG_MIN) {
				ZVAL_STRINGL(data, (char *)sqlite3_column_text(stmt, column), sqlite3_column_bytes(stmt, column));
			} else {
#endif
				ZVAL_LONG(data, (zend_long) val);
#if LONG_MAX <= 2147483647
			}
#endif
			break;

		case SQLITE_FLOAT:
			ZVAL_DOUBLE(data, sqlite3_column_double(stmt, column));
			break;

		case SQLITE_NULL:
			ZVAL_NULL(data);
			break;

		case SQLITE3_TEXT:
			ZVAL_STRING(data, (char*)sqlite3_column_text(stmt, column));
			break;

		case SQLITE_BLOB:
		default:
			ZVAL_STRINGL(data, (char*)sqlite3_column_blob(stmt, column), sqlite3_column_bytes(stmt, column));
	}
}
/* }}} */

/* {{{ Returns a string of the first column, or an array of the entire row. */
PHP_METHOD(SQLite3, querySingle)
{
	php_sqlite3_db_object *db_obj;
	zval *object = ZEND_THIS;
	zend_string *sql;
	char *errtext = NULL;
	int return_code;
	bool entire_row = 0;
	sqlite3_stmt *stmt;
	db_obj = Z_SQLITE3_DB_P(object);

	if (FAILURE == zend_parse_parameters(ZEND_NUM_ARGS(), "S|b", &sql, &entire_row)) {
		RETURN_THROWS();
	}

	SQLITE3_CHECK_INITIALIZED(db_obj, db_obj->initialised, SQLite3)

	if (!ZSTR_LEN(sql)) {
		RETURN_FALSE;
	}

	/* If there was no return value then just execute the query */
	if (!USED_RET()) {
		if (sqlite3_exec(db_obj->db, ZSTR_VAL(sql), NULL, NULL, &errtext) != SQLITE_OK) {
			php_sqlite3_error(db_obj, "%s", errtext);
			sqlite3_free(errtext);
		}
		RETURN_FALSE;
	}

	return_code = sqlite3_prepare_v2(db_obj->db, ZSTR_VAL(sql), ZSTR_LEN(sql), &stmt, NULL);
	if (return_code != SQLITE_OK) {
		php_sqlite3_error(db_obj, "Unable to prepare statement: %d, %s", return_code, sqlite3_errmsg(db_obj->db));
		RETURN_FALSE;
	}

	return_code = sqlite3_step(stmt);

	switch (return_code) {
		case SQLITE_ROW: /* Valid Row */
		{
			if (!entire_row) {
				sqlite_value_to_zval(stmt, 0, return_value);
			} else {
				int i = 0;
				array_init(return_value);
				for (i = 0; i < sqlite3_data_count(stmt); i++) {
					zval data;
					sqlite_value_to_zval(stmt, i, &data);
					add_assoc_zval(return_value, (char*)sqlite3_column_name(stmt, i), &data);
				}
			}
			break;
		}
		case SQLITE_DONE: /* Valid but no results */
		{
			if (!entire_row) {
				RETVAL_NULL();
			} else {
				RETVAL_EMPTY_ARRAY();
			}
			break;
		}
		default:
		if (!EG(exception)) {
			php_sqlite3_error(db_obj, "Unable to execute statement: %s", sqlite3_errmsg(db_obj->db));
		}
		RETVAL_FALSE;
	}
	sqlite3_finalize(stmt);
}
/* }}} */

static int sqlite3_do_callback(struct php_sqlite3_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;
	php_sqlite3_agg_context *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 = (zval *)safe_emalloc(fake_argc, sizeof(zval), 0);
	}

	if (is_agg) {
		/* summon the aggregation context */
		agg_context = (php_sqlite3_agg_context *)sqlite3_aggregate_context(context, sizeof(php_sqlite3_agg_context));

		if (Z_ISUNDEF(agg_context->zval_context)) {
			ZVAL_NULL(&agg_context->zval_context);
		}
		ZVAL_COPY(&zargs[0], &agg_context->zval_context);
		ZVAL_LONG(&zargs[1], agg_context->row_count);
	}

	for (i = 0; i < argc; i++) {
		switch (sqlite3_value_type(argv[i])) {
			case SQLITE_INTEGER:
#if ZEND_LONG_MAX > 2147483647
				ZVAL_LONG(&zargs[i + is_agg], sqlite3_value_int64(argv[i]));
#else
				ZVAL_LONG(&zargs[i + is_agg], sqlite3_value_int(argv[i]));
#endif
				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");
	}

	if (is_agg) {
		zval_ptr_dtor(&zargs[0]);
	}

	/* clean up the params */
	if (fake_argc) {
		for (i = is_agg; i < argc + is_agg; 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:
#if ZEND_LONG_MAX > 2147483647
					sqlite3_result_int64(context, Z_LVAL(retval));
#else
					sqlite3_result_int(context, Z_LVAL(retval));
#endif
					break;

				case IS_NULL:
					sqlite3_result_null(context);
					break;

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

				default: {
					zend_string *str = zval_try_get_string(&retval);
					if (UNEXPECTED(!str)) {
						ret = FAILURE;
						break;
					}
					sqlite3_result_text(context, ZSTR_VAL(str), ZSTR_LEN(str), SQLITE_TRANSIENT);
					zend_string_release(str);
					break;
				}
			}
		} else {
			sqlite3_result_error(context, "failed to invoke callback", 0);
		}

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

	if (!Z_ISUNDEF(retval)) {
		zval_ptr_dtor(&retval);
	}
	return ret;
}
/* }}}*/

static void php_sqlite3_callback_func(sqlite3_context *context, int argc, sqlite3_value **argv) /* {{{ */
{
	php_sqlite3_func *func = (php_sqlite3_func *)sqlite3_user_data(context);

	sqlite3_do_callback(&func->afunc, &func->func, argc, argv, context, 0);
}
/* }}}*/

static void php_sqlite3_callback_step(sqlite3_context *context, int argc, sqlite3_value **argv) /* {{{ */
{
	php_sqlite3_func *func = (php_sqlite3_func *)sqlite3_user_data(context);
	php_sqlite3_agg_context *agg_context = (php_sqlite3_agg_context *)sqlite3_aggregate_context(context, sizeof(php_sqlite3_agg_context));

	agg_context->row_count++;

	sqlite3_do_callback(&func->astep, &func->step, argc, argv, context, 1);
}
/* }}} */

static void php_sqlite3_callback_final(sqlite3_context *context) /* {{{ */
{
	php_sqlite3_func *func = (php_sqlite3_func *)sqlite3_user_data(context);
	php_sqlite3_agg_context *agg_context = (php_sqlite3_agg_context *)sqlite3_aggregate_context(context, sizeof(php_sqlite3_agg_context));

	agg_context->row_count = 0;

	sqlite3_do_callback(&func->afini, &func->fini, 0, NULL, context, 1);
}
/* }}} */

static int php_sqlite3_callback_compare(void *coll, int a_len, const void *a, int b_len, const void* b) /* {{{ */
{
	php_sqlite3_collation *collation = (php_sqlite3_collation*)coll;
	zval zargs[2];
	zval retval;
	int ret;

	// Exception occurred on previous callback. Don't attempt to call function.
	if (EG(exception)) {
		return 0;
	}

	collation->fci.fci.size = (sizeof(collation->fci.fci));
	ZVAL_COPY_VALUE(&collation->fci.fci.function_name, &collation->cmp_func);
	collation->fci.fci.object = NULL;
	collation->fci.fci.retval = &retval;
	collation->fci.fci.param_count = 2;

	ZVAL_STRINGL(&zargs[0], a, a_len);
	ZVAL_STRINGL(&zargs[1], b, b_len);

	collation->fci.fci.params = zargs;

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

	zval_ptr_dtor(&zargs[0]);
	zval_ptr_dtor(&zargs[1]);

	if (EG(exception)) {
		ret = 0;
	} else if (Z_TYPE(retval) != IS_LONG){
		//retval ought to contain a ZVAL_LONG by now
		// (the result of a comparison, i.e. most likely -1, 0, or 1)
		//I suppose we could accept any scalar return type, though.
		php_error_docref(NULL, E_WARNING, "An error occurred while invoking the compare callback (invalid return type).  Collation behaviour is undefined.");
	} else {
		ret = Z_LVAL(retval);
	}

	zval_ptr_dtor(&retval);

	return ret;
}
/* }}} */

/* {{{ Allows registration of a PHP function as a SQLite UDF that can be called within SQL statements. */
PHP_METHOD(SQLite3, createFunction)
{
	php_sqlite3_db_object *db_obj;
	zval *object = ZEND_THIS;
	php_sqlite3_func *func;
	char *sql_func;
	size_t sql_func_len;
	zend_fcall_info fci;
	zend_fcall_info_cache fcc;
	zend_long sql_func_num_args = -1;
	zend_long flags = 0;
	db_obj = Z_SQLITE3_DB_P(object);

	if (zend_parse_parameters(ZEND_NUM_ARGS(), "sf|ll", &sql_func, &sql_func_len, &fci, &fcc, &sql_func_num_args, &flags) == FAILURE) {
		RETURN_THROWS();
	}

	SQLITE3_CHECK_INITIALIZED(db_obj, db_obj->initialised, SQLite3)

	if (!sql_func_len) {
		RETURN_FALSE;
	}

	func = (php_sqlite3_func *)ecalloc(1, sizeof(*func));

	if (sqlite3_create_function(db_obj->db, sql_func, sql_func_num_args, flags | SQLITE_UTF8, func, php_sqlite3_callback_func, NULL, NULL) == SQLITE_OK) {
		func->func_name = estrdup(sql_func);

		ZVAL_COPY(&func->func, &fci.function_name);

		func->argc = sql_func_num_args;
		func->next = db_obj->funcs;
		db_obj->funcs = func;

		RETURN_TRUE;
	}
	efree(func);

	RETURN_FALSE;
}
/* }}} */

/* {{{ Allows registration of a PHP function for use as an aggregate. */
PHP_METHOD(SQLite3, createAggregate)
{
	php_sqlite3_db_object *db_obj;
	zval *object = ZEND_THIS;
	php_sqlite3_func *func;
	char *sql_func;
	size_t sql_func_len;
	zend_fcall_info step_fci, fini_fci;
	zend_fcall_info_cache step_fcc, fini_fcc;