Horde_HashTable_Vfs::hkey PHP Method

    public function hkey($key)
    {
        /* Key is SHA-1 encoded (can't use FNV1-32 here, since key must be
         * the same if upgrading from PHP 5.3 -> 5.4+). */
        return hash('sha1', $this->_params['prefix'] . $key);
    }