nextcloud/lib/private/Lock/AbstractLockingProvider.php

120 lines
3.5 KiB
PHP

<?php
/**
* @author Robin Appelman <icewind@owncloud.com>
*
* @copyright Copyright (c) 2016, ownCloud, Inc.
* @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\Lock;
use OCP\Lock\ILockingProvider;
/**
* Base locking provider that keeps track of locks acquired during the current request
* to release any left over locks at the end of the request
*/
abstract class AbstractLockingProvider implements ILockingProvider {
protected $ttl; // how long until we clear stray locks in seconds
protected $acquiredLocks = [
'shared' => [],
'exclusive' => []
];
/**
* Check if we've locally acquired a lock
*
* @param string $path
* @param int $type
* @return bool
*/
protected function hasAcquiredLock($path, $type) {
if ($type === self::LOCK_SHARED) {
return isset($this->acquiredLocks['shared'][$path]) && $this->acquiredLocks['shared'][$path] > 0;
} else {
return isset($this->acquiredLocks['exclusive'][$path]) && $this->acquiredLocks['exclusive'][$path] === true;
}
}
/**
* Mark a locally acquired lock
*
* @param string $path
* @param int $type self::LOCK_SHARED or self::LOCK_EXCLUSIVE
*/
protected function markAcquire($path, $type) {
if ($type === self::LOCK_SHARED) {
if (!isset($this->acquiredLocks['shared'][$path])) {
$this->acquiredLocks['shared'][$path] = 0;
}
$this->acquiredLocks['shared'][$path]++;
} else {
$this->acquiredLocks['exclusive'][$path] = true;
}
}
/**
* Mark a release of a locally acquired lock
*
* @param string $path
* @param int $type self::LOCK_SHARED or self::LOCK_EXCLUSIVE
*/
protected function markRelease($path, $type) {
if ($type === self::LOCK_SHARED) {
if (isset($this->acquiredLocks['shared'][$path]) and $this->acquiredLocks['shared'][$path] > 0) {
$this->acquiredLocks['shared'][$path]--;
}
} else if ($type === self::LOCK_EXCLUSIVE) {
unset($this->acquiredLocks['exclusive'][$path]);
}
}
/**
* Change the type of an existing tracked lock
*
* @param string $path
* @param int $targetType self::LOCK_SHARED or self::LOCK_EXCLUSIVE
*/
protected function markChange($path, $targetType) {
if ($targetType === self::LOCK_SHARED) {
unset($this->acquiredLocks['exclusive'][$path]);
if (!isset($this->acquiredLocks['shared'][$path])) {
$this->acquiredLocks['shared'][$path] = 0;
}
$this->acquiredLocks['shared'][$path]++;
} else if ($targetType === self::LOCK_EXCLUSIVE) {
$this->acquiredLocks['exclusive'][$path] = true;
$this->acquiredLocks['shared'][$path]--;
}
}
/**
* release all lock acquired by this instance which were marked using the mark* methods
*/
public function releaseAll() {
foreach ($this->acquiredLocks['shared'] as $path => $count) {
for ($i = 0; $i < $count; $i++) {
$this->releaseLock($path, self::LOCK_SHARED);
}
}
foreach ($this->acquiredLocks['exclusive'] as $path => $hasLock) {
$this->releaseLock($path, self::LOCK_EXCLUSIVE);
}
}
}