57 lines
1.4 KiB
PHP
57 lines
1.4 KiB
PHP
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<?php
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/**
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* @author Robin Appelman <icewind@owncloud.com>
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*
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* @copyright Copyright (c) 2015, ownCloud, Inc.
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* @license AGPL-3.0
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*
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* This code is free software: you can redistribute it and/or modify
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* it under the terms of the GNU Affero General Public License, version 3,
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* as published by the Free Software Foundation.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU Affero General Public License for more details.
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*
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* You should have received a copy of the GNU Affero General Public License, version 3,
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* along with this program. If not, see <http://www.gnu.org/licenses/>
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*
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*/
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namespace OC\Memcache;
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trait CASTrait {
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abstract public function get($key);
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abstract public function set($key, $value, $ttl = 0);
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abstract public function remove($key);
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abstract public function add($key, $value, $ttl = 0);
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/**
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* Compare and set
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*
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* @param string $key
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* @param mixed $old
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* @param mixed $new
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* @return bool
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*/
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public function cas($key, $old, $new) {
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//no native cas, emulate with locking
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if ($this->add($key . '_lock', true)) {
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if ($this->get($key) === $old) {
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$this->set($key, $new);
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$this->remove($key . '_lock');
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return true;
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} else {
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$this->remove($key . '_lock');
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return false;
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}
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} else {
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return false;
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}
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}
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}
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