Search moodle.org's
Developer Documentation

See Release Notes
Long Term Support Release

  • Bug fixes for general core bugs in 4.1.x will end 13 November 2023 (12 months).
  • Bug fixes for security issues in 4.1.x will end 10 November 2025 (36 months).
  • PHP version: minimum PHP 7.4.0 Note: minimum PHP version has increased since Moodle 4.0. PHP 8.0.x is supported too.
<?php
// This file is part of Moodle - http://moodle.org/
//
// Moodle is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// Moodle 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 General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.

< /** < * Class representing a lock < * < * The methods available for a specific lock type are only known by it's factory. < * < * @package core < * @copyright Damyon Wiese 2013 < * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later < */ <
namespace core\lock;
< defined('MOODLE_INTERNAL') || die();
> use coding_exception;
/** * Class representing a lock * * The methods available for a specific lock type are only known by it's factory. * * @package core * @category lock * @copyright Damyon Wiese 2013 * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later */ class lock { /** @var string|int $key A unique key representing a held lock */ protected $key = ''; /** @var lock_factory $factory The factory that generated this lock */ protected $factory; /** @var bool $released Has this lock been released? If a lock falls out of scope without being released - show a warning. */ protected $released; /** @var string $caller Where was this called from? Stored for when a warning is shown */ protected $caller = 'unknown'; /** * Construct a lock containing the unique key required to release it. * @param mixed $key - The lock key. The type of this is up to the lock_factory being used. * For file locks this is a file handle. For MySQL this is a string. * @param lock_factory $factory - The factory that generated this lock. */ public function __construct($key, $factory) { $this->factory = $factory; $this->key = $key; $this->released = false; $caller = debug_backtrace(true, 2)[1]; if ($caller && array_key_exists('file', $caller ) ) { $this->caller = $caller['file'] . ' on line ' . $caller['line']; } else if ($caller && array_key_exists('class', $caller)) { $this->caller = $caller['class'] . $caller['type'] . $caller['function']; } } /** * Sets the lock factory that owns a lock. This function should not be called under normal use. * It is intended only for cases like {@see timing_wrapper_lock_factory} where we wrap a lock * factory. * * When used, it should be called immediately after constructing the lock. * * @param lock_factory $factory New lock factory that owns this lock */ public function init_factory(lock_factory $factory): void { $this->factory = $factory; } /** * Return the unique key representing this lock. * @return string|int lock key. */ public function get_key() { return $this->key; } /**
< * Extend the lifetime of this lock. Not supported by all factories. < *
* @deprecated since Moodle 3.10.
< * @param int $maxlifetime - the new lifetime for the lock (in seconds). < * @return bool
*/
< public function extend($maxlifetime = 86400) { < debugging('The function extend() is deprecated, please do not use it anymore.', < DEBUG_DEVELOPER); < < if ($this->factory) { < return $this->factory->extend_lock($this, $maxlifetime); < } < return false;
> public function extend() { > throw new coding_exception('The function extend() has been removed, please do not use it anymore.');
} /** * Release this lock * @return bool */ public function release() { $this->released = true; if (empty($this->factory)) { return false; } $result = $this->factory->release_lock($this); // Release any held references to the factory. unset($this->factory); $this->factory = null; $this->key = ''; return $result; } /** * Print debugging if this lock falls out of scope before being released. */ public function __destruct() { if (!$this->released && defined('PHPUNIT_TEST')) { $key = $this->key; $this->release(); throw new \coding_exception("A lock was created but not released at:\n" . $this->caller . "\n\n" . " Code should look like:\n\n" . " \$factory = \core\lock\lock_config::get_lock_factory('type');\n" . " \$lock = \$factory->get_lock($key);\n" . " \$lock->release(); // Locks must ALWAYS be released like this.\n\n"); } } }