public static function createSession($user_id) { //returns session string $prfx = DB_PREFIX; //test if session for user_id is already set $open_session_rows = Data::getRow("SELECT * FROM {$prfx}session WHERE user_id={$user_id}"); $session_id = RequestUtils::random_str(24); if (!$open_session_rows) { //session for the user is NOT YET created Data::submitModificationQuery("INSERT INTO {$prfx}session (session_id, user_id) VALUES ('{$session_id}', {$user_id})"); } else { //session for the user is ALREADY created Data::submitModificationQuery("UPDATE {$prfx}session SET session_id='{$session_id}' WHERE user_id={$user_id}"); } return $session_id; }
/** * returns a temporary file for the problem with the specified id * @param $id * @return unknown_type */ function getTemporaryProblemFile() { return $GLOBALS['dces_dir_temp'] . '/' . RequestUtils::random_str(10) . '.problem'; }