gluon-web-remote

Web remote Administration for big size of gluon routers
git clone git://archive.git.mtrnord.blog/MTRNord/gluon-web-remote.git
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LockHandler.php (3426B)

      1 <?php
      2 
      3 /*
      4  * This file is part of the Symfony package.
      5  *
      6  * (c) Fabien Potencier <fabien@symfony.com>
      7  *
      8  * For the full copyright and license information, please view the LICENSE
      9  * file that was distributed with this source code.
     10  */
     11 
     12 namespace Symfony\Component\Filesystem;
     13 
     14 use Symfony\Component\Filesystem\Exception\IOException;
     15 
     16 /**
     17  * LockHandler class provides a simple abstraction to lock anything by means of
     18  * a file lock.
     19  *
     20  * A locked file is created based on the lock name when calling lock(). Other
     21  * lock handlers will not be able to lock the same name until it is released
     22  * (explicitly by calling release() or implicitly when the instance holding the
     23  * lock is destroyed).
     24  *
     25  * @author Grégoire Pineau <lyrixx@lyrixx.info>
     26  * @author Romain Neutron <imprec@gmail.com>
     27  * @author Nicolas Grekas <p@tchwork.com>
     28  */
     29 class LockHandler
     30 {
     31     private $file;
     32     private $handle;
     33 
     34     /**
     35      * @param string      $name     The lock name
     36      * @param string|null $lockPath The directory to store the lock. Default values will use temporary directory
     37      *
     38      * @throws IOException If the lock directory could not be created or is not writable
     39      */
     40     public function __construct($name, $lockPath = null)
     41     {
     42         $lockPath = $lockPath ?: sys_get_temp_dir();
     43 
     44         if (!is_dir($lockPath)) {
     45             $fs = new Filesystem();
     46             $fs->mkdir($lockPath);
     47         }
     48 
     49         if (!is_writable($lockPath)) {
     50             throw new IOException(sprintf('The directory "%s" is not writable.', $lockPath), 0, null, $lockPath);
     51         }
     52 
     53         $this->file = sprintf('%s/sf.%s.%s.lock', $lockPath, preg_replace('/[^a-z0-9\._-]+/i', '-', $name), hash('sha256', $name));
     54     }
     55 
     56     /**
     57      * Lock the resource.
     58      *
     59      * @param bool $blocking wait until the lock is released
     60      *
     61      * @return bool Returns true if the lock was acquired, false otherwise
     62      *
     63      * @throws IOException If the lock file could not be created or opened
     64      */
     65     public function lock($blocking = false)
     66     {
     67         if ($this->handle) {
     68             return true;
     69         }
     70 
     71         // Silence both userland and native PHP error handlers
     72         $errorLevel = error_reporting(0);
     73         set_error_handler('var_dump', 0);
     74 
     75         if (!$this->handle = fopen($this->file, 'r')) {
     76             if ($this->handle = fopen($this->file, 'x')) {
     77                 chmod($this->file, 0444);
     78             } elseif (!$this->handle = fopen($this->file, 'r')) {
     79                 usleep(100); // Give some time for chmod() to complete
     80                 $this->handle = fopen($this->file, 'r');
     81             }
     82         }
     83         restore_error_handler();
     84         error_reporting($errorLevel);
     85 
     86         if (!$this->handle) {
     87             $error = error_get_last();
     88             throw new IOException($error['message'], 0, null, $this->file);
     89         }
     90 
     91         // On Windows, even if PHP doc says the contrary, LOCK_NB works, see
     92         // https://bugs.php.net/54129
     93         if (!flock($this->handle, LOCK_EX | ($blocking ? 0 : LOCK_NB))) {
     94             fclose($this->handle);
     95             $this->handle = null;
     96 
     97             return false;
     98         }
     99 
    100         return true;
    101     }
    102 
    103     /**
    104      * Release the resource.
    105      */
    106     public function release()
    107     {
    108         if ($this->handle) {
    109             flock($this->handle, LOCK_UN | LOCK_NB);
    110             fclose($this->handle);
    111             $this->handle = null;
    112         }
    113     }
    114 }