<?php
/*
* This file is part of the Symfony package.
*
* (c) Fabien Potencier <fabien@symfony.com>
*
* For the full copyright and license information, please view the LICENSE
* file that was distributed with this source code.
*/
namespace Symfony\Component\Filesystem;
use Symfony\Component\Filesystem\Exception\IOException;
use Symfony\Component\Lock\Store\FlockStore;
use Symfony\Component\Lock\Store\SemaphoreStore;
@trigger_error(sprintf('The %s class is deprecated since Symfony 3.4 and will be removed in 4.0. Use %s or %s instead.', LockHandler::class, SemaphoreStore::class, FlockStore::class), \E_USER_DEPRECATED);
/**
* LockHandler class provides a simple abstraction to lock anything by means of
* a file lock.
*
* A locked file is created based on the lock name when calling lock(). Other
* lock handlers will not be able to lock the same name until it is released
* (explicitly by calling release() or implicitly when the instance holding the
* lock is destroyed).
*
* @author Grégoire Pineau <lyrixx@lyrixx.info>
* @author Romain Neutron <imprec@gmail.com>
* @author Nicolas Grekas <p@tchwork.com>
*
* @deprecated since version 3.4, to be removed in 4.0. Use Symfony\Component\Lock\Store\SemaphoreStore or Symfony\Component\Lock\Store\FlockStore instead.
*/
class LockHandler
{
private $file;
private $handle;
/**
* @param string $name The lock name
* @param string|null $lockPath The directory to store the lock. Default values will use temporary directory
*
* @throws IOException If the lock directory could not be created or is not writable
*/
public function __construct($name, $lockPath = null)
{
$lockPath = $lockPath ?: sys_get_temp_dir();
if (!is_dir($lockPath)) {
$fs = new Filesystem();
$fs->mkdir($lockPath);
}
if (!is_writable($lockPath)) {
throw new IOException(sprintf('The directory "%s" is not writable.', $lockPath), 0, null, $lockPath);
}
$this->file = sprintf('%s/sf.%s.%s.lock', $lockPath, preg_replace('/[^a-z0-9\._-]+/i', '-', $name), hash('sha256', $name));
}
/**
* Lock the resource.
*
* @param bool $blocking Wait until the lock is released
*
* @return bool Returns true if the lock was acquired, false otherwise
*
* @throws IOException If the lock file could not be created or opened
*/
public function lock($blocking = false)
{
if ($this->handle) {
return true;
}
$error = null;
// Silence error reporting
set_error_handler(function ($errno, $msg) use (&$error) {
$error = $msg;
});
if (!$this->handle = fopen($this->file, 'r+') ?: fopen($this->file, 'r')) {
if ($this->handle = fopen($this->file, 'x')) {
chmod($this->file, 0666);
} elseif (!$this->handle = fopen($this->file, 'r+') ?: fopen($this->file, 'r')) {
usleep(100); // Give some time for chmod() to complete
$this->handle = fopen($this->file, 'r+') ?: fopen($this->file, 'r');
}
}
restore_error_handler();
if (!$this->handle) {
throw new IOException($error, 0, null, $this->file);
}
// On Windows, even if PHP doc says the contrary, LOCK_NB works, see
// https://bugs.php.net/54129
if (!flock($this->handle, \LOCK_EX | ($blocking ? 0 : \LOCK_NB))) {
fclose($this->handle);
$this->handle = null;
return false;
}
return true;
}
/**
* Release the resource.
*/
public function release()
{
if ($this->handle) {
flock($this->handle, \LOCK_UN | \LOCK_NB);
fclose($this->handle);
$this->handle = null;
}
}
}