/lib/classes/shutdown_manager.php
PHP | 235 lines | 122 code | 22 blank | 91 comment | 26 complexity | 59bd8d44e678a18232273dd4d7fa83cc MD5 | raw file
- <?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/>.
- /**
- * Shutdown management class.
- *
- * @package core
- * @copyright 2013 Petr Skoda {@link http://skodak.org}
- * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
- */
- defined('MOODLE_INTERNAL') || die();
- /**
- * Shutdown management class.
- *
- * @package core
- * @copyright 2013 Petr Skoda {@link http://skodak.org}
- * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
- */
- class core_shutdown_manager {
- /** @var array list of custom callbacks */
- protected static $callbacks = [];
- /** @var array list of custom signal callbacks */
- protected static $signalcallbacks = [];
- /** @var bool is this manager already registered? */
- protected static $registered = false;
- /**
- * Register self as main shutdown handler.
- *
- * @private to be called from lib/setup.php only!
- */
- public static function initialize() {
- if (self::$registered) {
- debugging('Shutdown manager is already initialised!');
- }
- self::$registered = true;
- register_shutdown_function(array('core_shutdown_manager', 'shutdown_handler'));
- // Signal handlers should only be used when dealing with a CLI script.
- // In the case of PHP called in a web server the server is the owning process and should handle the signal chain
- // properly itself.
- // The 'pcntl' extension is optional and not available on Windows.
- if (CLI_SCRIPT && extension_loaded('pcntl') && function_exists('pcntl_async_signals')) {
- // We capture and handle SIGINT (Ctrl+C) and SIGTERM (termination requested).
- pcntl_async_signals(true);
- pcntl_signal(SIGINT, ['core_shutdown_manager', 'signal_handler']);
- pcntl_signal(SIGTERM, ['core_shutdown_manager', 'signal_handler']);
- }
- }
- /**
- * Signal handler for SIGINT, and SIGTERM.
- *
- * @param int $signo The signal being handled
- */
- public static function signal_handler(int $signo) {
- // Note: There is no need to manually call the shutdown handler.
- // The fact that we are calling exit() in this script means that the standard shutdown handling is performed
- // anyway.
- switch ($signo) {
- case SIGTERM:
- // Replicate native behaviour.
- echo "Terminated: {$signo}\n";
- // The standard exit code for SIGTERM is 143.
- $exitcode = 143;
- break;
- case SIGINT:
- // Replicate native behaviour.
- echo "\n";
- // The standard exit code for SIGINT (Ctrl+C) is 130.
- $exitcode = 130;
- break;
- default:
- // The signal handler was called with a signal it was not expecting.
- // We should exit and complain.
- echo "Warning: \core_shutdown_manager::signal_handler() was called with an unexpected signal ({$signo}).\n";
- $exitcode = 1;
- }
- // Normally we should exit unless a callback tells us to wait.
- $shouldexit = true;
- foreach (self::$signalcallbacks as $data) {
- list($callback, $params) = $data;
- try {
- array_unshift($params, $signo);
- $shouldexit = call_user_func_array($callback, $params) && $shouldexit;
- } catch (Throwable $e) {
- // phpcs:ignore
- error_log('Exception ignored in signal function ' . get_callable_name($callback) . ': ' . $e->getMessage());
- }
- }
- if ($shouldexit) {
- exit ($exitcode);
- }
- }
- /**
- * Register custom signal handler function.
- *
- * If a handler returns false the signal will be ignored.
- *
- * @param callable $callback
- * @param array $params
- * @return void
- */
- public static function register_signal_handler($callback, array $params = null): void {
- if (!is_callable($callback)) {
- error_log('Invalid custom signal function detected ' . var_export($callback, true)); // phpcs:ignore
- }
- self::$signalcallbacks[] = [$callback, $params ?? []];
- }
- /**
- * Register custom shutdown function.
- *
- * @param callable $callback
- * @param array $params
- * @return void
- */
- public static function register_function($callback, array $params = null): void {
- if (!is_callable($callback)) {
- error_log('Invalid custom shutdown function detected '.var_export($callback, true)); // phpcs:ignore
- }
- self::$callbacks[] = [$callback, $params ? array_values($params) : []];
- }
- /**
- * @private - do NOT call directly.
- */
- public static function shutdown_handler() {
- global $DB;
- // Custom stuff first.
- foreach (self::$callbacks as $data) {
- list($callback, $params) = $data;
- try {
- call_user_func_array($callback, $params);
- } catch (Throwable $e) {
- // phpcs:ignore
- error_log('Exception ignored in shutdown function '.get_callable_name($callback).': '.$e->getMessage());
- }
- }
- // Handle DB transactions, session need to be written afterwards
- // in order to maintain consistency in all session handlers.
- if ($DB->is_transaction_started()) {
- if (!defined('PHPUNIT_TEST') or !PHPUNIT_TEST) {
- // This should not happen, it usually indicates wrong catching of exceptions,
- // because all transactions should be finished manually or in default exception handler.
- $backtrace = $DB->get_transaction_start_backtrace();
- error_log('Potential coding error - active database transaction detected during request shutdown:'."\n".format_backtrace($backtrace, true));
- }
- $DB->force_transaction_rollback();
- }
- // Close sessions - do it here to make it consistent for all session handlers.
- \core\session\manager::write_close();
- // Other cleanup.
- self::request_shutdown();
- // Stop profiling.
- if (function_exists('profiling_is_running')) {
- if (profiling_is_running()) {
- profiling_stop();
- }
- }
- // NOTE: do not dispose $DB and MUC here, they might be used from legacy shutdown functions.
- }
- /**
- * Standard shutdown sequence.
- */
- protected static function request_shutdown() {
- global $CFG;
- // Help apache server if possible.
- $apachereleasemem = false;
- if (function_exists('apache_child_terminate') && function_exists('memory_get_usage') && ini_get_bool('child_terminate')) {
- $limit = (empty($CFG->apachemaxmem) ? 64*1024*1024 : $CFG->apachemaxmem); // 64MB default.
- if (memory_get_usage() > get_real_size($limit)) {
- $apachereleasemem = $limit;
- @apache_child_terminate();
- }
- }
- // Deal with perf logging.
- if (defined('MDL_PERF') || (!empty($CFG->perfdebug) and $CFG->perfdebug > 7)) {
- if ($apachereleasemem) {
- error_log('Mem usage over '.$apachereleasemem.': marking Apache child for reaping.');
- }
- if (defined('MDL_PERFTOLOG')) {
- $perf = get_performance_info();
- error_log("PERF: " . $perf['txt']);
- }
- if (defined('MDL_PERFINC')) {
- $inc = get_included_files();
- $ts = 0;
- foreach ($inc as $f) {
- if (preg_match(':^/:', $f)) {
- $fs = filesize($f);
- $ts += $fs;
- $hfs = display_size($fs);
- error_log(substr($f, strlen($CFG->dirroot)) . " size: $fs ($hfs)", null, null, 0);
- } else {
- error_log($f , null, null, 0);
- }
- }
- if ($ts > 0 ) {
- $hts = display_size($ts);
- error_log("Total size of files included: $ts ($hts)");
- }
- }
- }
- }
- }