Gaufrette\Adapter\Ftp::listKeys PHP Method

    public function listKeys($prefix = '')
    {
        $this->ensureDirectoryExists($this->directory, $this->create);
        preg_match('/(.*?)[^\\/]*$/', $prefix, $match);
        $directory = rtrim($match[1], '/');
        $keys = $this->fetchKeys($directory, false);
        if ($directory === $prefix) {
            return $keys;
        }
        $filteredKeys = array();
        foreach (array('keys', 'dirs') as $hash) {
            $filteredKeys[$hash] = array();
            foreach ($keys[$hash] as $key) {
                if (0 === strpos($key, $prefix)) {
                    $filteredKeys[$hash][] = $key;
                }
            }
        }
        return $filteredKeys;
    }