Merge branch 'w41_MDL-42040_m26_shutdown' of https://github.com/skodak/moodle

lib/classes/session/database.php

@@ -79,8 +79,6 @@ class database extends handler {
         if (!$result) {
             throw new exception('dbsessionhandlerproblem', 'error');
         }
-
-        register_shutdown_function(array($this, 'handler_shutdown'));
     }
 
     /**
@@ -305,11 +303,4 @@ class database extends handler {
         $this->database->delete_records_select('sessions', 'userid = 0 AND timemodified < :purgebefore', $params);
         return true;
     }
-
-    /**
-     * This makes sure the session is written to disk at the end of request.
-     */
-    public function handler_shutdown() {
-        $this->database->dispose();
-    }
 }

lib/classes/shutdown_manager.php

@@ -0,0 +1,160 @@
+<?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 = array();
+    /** @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'));
+    }
+
+    /**
+     * Register custom shutdown function.
+     *
+     * @param callable $callback
+     * @param array $params
+     */
+    public static function register_function($callback, array $params = null) {
+        self::$callbacks[] = array($callback, $params);
+    }
+
+    /**
+     * @private - do NOT call directly.
+     */
+    public static function shutdown_handler() {
+        global $DB;
+
+        // Custom stuff first.
+        foreach (self::$callbacks as $data) {
+            list($callback, $params) = $data;
+            try {
+                if (!is_callable($callback)) {
+                    error_log('Invalid custom shutdown function detected '.var_export($callback, true));
+                    continue;
+                }
+                if ($params === null) {
+                    call_user_func($callback);
+                } else {
+                    call_user_func_array($callback, $params);
+                }
+            } catch (Exception $e) {
+                error_log('Exception ignored in shutdown function '.var_export($callback, true).':'.$e->getMessage());
+            }
+        }
+
+        // Handle DB transactions, session need to be written afterwards
+        // in order to maintain consistency in all session handlers.
+        if ($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)");
+                }
+            }
+        }
+    }
+}