<?php
/**
* @package Freemius
* @copyright Copyright (c) 2015, Freemius, Inc.
* @license https://www.gnu.org/licenses/gpl-3.0.html GNU General Public License Version 3
* @since 2.5.1
*/
if ( ! defined( 'ABSPATH' ) ) {
exit;
}
/**
* Class FS_Lock
*
* @author Vova Feldman (@svovaf)
* @since 2.5.1
*/
class FS_Lock {
/**
* @var int Random ID representing the current PHP thread.
*/
private static $_thread_id;
/**
* @var string
*/
private $_lock_id;
/**
* @param string $lock_id
*/
function __construct( $lock_id ) {
if ( ! fs_starts_with( $lock_id, WP_FS___OPTION_PREFIX ) ) {
$lock_id = WP_FS___OPTION_PREFIX . $lock_id;
}
$this->_lock_id = $lock_id;
if ( ! isset( self::$_thread_id ) ) {
self::$_thread_id = mt_rand( 0, 32000 );
}
}
/**
* Try to acquire lock. If the lock is already set or is being acquired by another locker, don't do anything.
*
* @param int $expiration
*
* @return bool TRUE if successfully acquired lock.
*/
function try_lock( $expiration = 0 ) {
if ( $this->is_locked() ) {
// Already locked.
return false;
}
set_site_transient( $this->_lock_id, self::$_thread_id, $expiration );
if ( $this->has_lock() ) {
$this->lock($expiration);
return true;
}
return false;
}
/**
* Acquire lock regardless if it's already acquired by another locker or not.
*
* @author Vova Feldman (@svovaf)
* @since 2.1.0
*
* @param int $expiration
*/
function lock( $expiration = 0 ) {
set_site_transient( $this->_lock_id, true, $expiration );
}
/**
* Checks if lock is currently acquired.
*
* @author Vova Feldman (@svovaf)
* @since 2.1.0
*
* @return bool
*/
function is_locked() {
return ( false !== get_site_transient( $this->_lock_id ) );
}
/**
* Unlock the lock.
*
* @author Vova Feldman (@svovaf)
* @since 2.1.0
*/
function unlock() {
delete_site_transient( $this->_lock_id );
}
/**
* Checks if lock is currently acquired by the current locker.
*
* @return bool
*/
protected function has_lock() {
return ( self::$_thread_id == get_site_transient( $this->_lock_id ) );
}
}