<?php
+/**
+ * @copyright Copyright (C) 2020, Friendica
+ *
+ * @license GNU AGPL version 3 or any later version
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * 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
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
namespace Friendica\Core\Lock;
-use Friendica\Core\Cache;
+use Friendica\Core\BaseLock;
+use Friendica\Core\Cache\Duration;
-class SemaphoreLock extends Lock
+class SemaphoreLock extends BaseLock
{
private static $semaphore = [];
*/
private static function semaphoreKey($key)
{
- $file = self::keyToFile($key);
+ $success = true;
- if (!file_exists($file)) {
- file_put_contents($file, $key);
- }
+ $temp = get_temppath();
- return ftok($file, 'f');
- }
+ $file = $temp . '/' . $key . '.sem';
- /**
- * Returns the full path to the semaphore file
- *
- * @param string $key The key of the semaphore
- *
- * @return string The full path
- */
- private static function keyToFile($key)
- {
- $temp = get_temppath();
+ if (!file_exists($file)) {
+ $success = !empty(file_put_contents($file, $key));
+ }
- return $temp . '/' . $key . '.sem';
+ return $success ? ftok($file, 'f') : false;
}
/**
* (@inheritdoc)
*/
- public function acquireLock($key, $timeout = 120, $ttl = Cache\Cache::FIVE_MINUTES)
+ public function acquire($key, $timeout = 120, $ttl = Duration::FIVE_MINUTES)
{
self::$semaphore[$key] = sem_get(self::semaphoreKey($key));
- if (self::$semaphore[$key]) {
- if (sem_acquire(self::$semaphore[$key], ($timeout == 0))) {
+ if (!empty(self::$semaphore[$key])) {
+ if ((bool)sem_acquire(self::$semaphore[$key], ($timeout === 0))) {
$this->markAcquire($key);
return true;
}
/**
* (@inheritdoc)
+ *
+ * @param bool $override not necessary parameter for semaphore locks since the lock lives as long as the execution
+ * of the using function
*/
- public function releaseLock($key, $override = false)
+ public function release($key, $override = false)
{
$success = false;
if (!empty(self::$semaphore[$key])) {
try {
- $success = @sem_release(self::$semaphore[$key]) &&
- unlink(self::keyToFile($key));
+ $success = @sem_release(self::$semaphore[$key]);
unset(self::$semaphore[$key]);
$this->markRelease($key);
} catch (\Exception $exception) {
$success = false;
}
- } else if ($override) {
- if ($this->acquireLock($key)) {
- $success = $this->releaseLock($key, true);
- }
}
return $success;
*/
public function getName()
{
- return self::TYPE_SEMAPHORE;
+ return Type::SEMAPHORE;
}
/**
*/
public function getLocks(string $prefix = '')
{
- $temp = get_temppath();
- $locks = [];
- foreach (glob(sprintf('%s/%s*.sem', $temp, $prefix)) as $lock) {
- $lock = pathinfo($lock, PATHINFO_FILENAME);
- if(sem_get(self::semaphoreKey($lock))) {
- $locks[] = $lock;
+ // We can just return our own semaphore keys, since we don't know
+ // the state of other semaphores, even if the .sem files exists
+ $keys = array_keys(self::$semaphore);
+
+ if (empty($prefix)) {
+ return $keys;
+ } else {
+ $result = [];
+
+ foreach ($keys as $key) {
+ if (strpos($key, $prefix) === 0) {
+ array_push($result, $key);
+ }
}
- }
- return $locks;
+ return $result;
+ }
}
/**
*/
public function releaseAll($override = false)
{
- $success = parent::releaseAll($override);
-
- $temp = get_temppath();
- foreach (glob(sprintf('%s/*.sem', $temp)) as $lock) {
- $lock = pathinfo($lock, PATHINFO_FILENAME);
- if (!$this->releaseLock($lock, true)) {
- $success = false;
- }
- }
-
- return $success;
+ // Semaphores are just alive during a run, so there is no need to release
+ // You can just release your own locks
+ return parent::releaseAll($override);
}
}