friendica/src/Util/Lock/SemaphoreLockDriver.php

82 lines
1.6 KiB
PHP

<?php
namespace Friendica\Util\Lock;
class SemaphoreLockDriver implements ILockDriver
{
/**
* @var array stored semaphores
*/
private static $semaphore = [];
/**
* @brief Creates a semaphore key
*
* @param string $key Name of the lock
*
* @return integer the semaphore key
*/
private static function semaphoreKey($key)
{
$temp = get_temppath();
$file = $temp.'/'.$key.'.sem';
if (!file_exists($file)) {
file_put_contents($file, $key);
}
return ftok($file, 'f');
}
/**
*
* @brief Sets a lock for a given name
*
* @param string $key The Name of the lock
* @param integer $timeout Seconds until we give up
*
* @return boolean Was the lock successful?
*/
public function acquireLock($key, $timeout = 120)
{
// The second parameter for "sem_acquire" doesn't exist before 5.6.1
if (function_exists('sem_get') && version_compare(PHP_VERSION, '5.6.1', '>=')) {
self::$semaphore[$key] = sem_get(self::semaphoreKey($key));
if (self::$semaphore[$key]) {
return sem_acquire(self::$semaphore[$key], ($timeout == 0));
}
}
}
/**
* @brief Removes a lock if it was set by us
*
* @param string $key Name of the lock
*
* @return mixed
*/
public function releaseLock($key)
{
if (function_exists('sem_get') && version_compare(PHP_VERSION, '5.6.1', '>=')) {
if (empty(self::$semaphore[$key])) {
return false;
} else {
$success = @sem_release(self::$semaphore[$key]);
unset(self::$semaphore[$key]);
return $success;
}
}
}
/**
* @brief Removes all lock that were set by us
*
* @return void
*/
public function releaseAll()
{
// not needed/supported
return;
}
}