nextcloud/lib/private/Memcache/CASTrait.php

58 lines
1.4 KiB
PHP

<?php
/**
* @copyright Copyright (c) 2016, ownCloud, Inc.
*
* @author Robin Appelman <robin@icewind.nl>
*
* @license AGPL-3.0
*
* This code is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License, version 3,
* as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License, version 3,
* along with this program. If not, see <http://www.gnu.org/licenses/>
*
*/
namespace OC\Memcache;
trait CASTrait {
abstract public function get($key);
abstract public function set($key, $value, $ttl = 0);
abstract public function remove($key);
abstract public function add($key, $value, $ttl = 0);
/**
* Compare and set
*
* @param string $key
* @param mixed $old
* @param mixed $new
* @return bool
*/
public function cas($key, $old, $new) {
//no native cas, emulate with locking
if ($this->add($key . '_lock', true)) {
if ($this->get($key) === $old) {
$this->set($key, $new);
$this->remove($key . '_lock');
return true;
} else {
$this->remove($key . '_lock');
return false;
}
} else {
return false;
}
}
}