MDL-42084 Core: Create new static class for use instead of set_time_limit

admin/settings/server.php

@@ -93,6 +93,7 @@ $options = array(
     GETREMOTEADDR_SKIP_HTTP_X_FORWARDED_FOR => 'HTTP_CLIENT, REMOTE_ADDR',
     GETREMOTEADDR_SKIP_HTTP_X_FORWARDED_FOR|GETREMOTEADDR_SKIP_HTTP_CLIENT_IP => 'REMOTE_ADDR');
 $temp->add(new admin_setting_configselect('getremoteaddrconf', new lang_string('getremoteaddrconf', 'admin'), new lang_string('configgetremoteaddrconf', 'admin'), 0, $options));
+
 $temp->add(new admin_setting_heading('webproxy', new lang_string('webproxy', 'admin'), new lang_string('webproxyinfo', 'admin')));
 $temp->add(new admin_setting_configtext('proxyhost', new lang_string('proxyhost', 'admin'), new lang_string('configproxyhost', 'admin'), '', PARAM_HOST));
 $temp->add(new admin_setting_configtext('proxyport', new lang_string('proxyport', 'admin'), new lang_string('configproxyport', 'admin'), 0, PARAM_INT));
@@ -195,6 +196,8 @@ if (PHP_INT_SIZE === 8) {
 $temp->add(new admin_setting_configselect('extramemorylimit', new lang_string('extramemorylimit', 'admin'),
                                           new lang_string('configextramemorylimit', 'admin'), '512M',
                                           $memoryoptions));
+$temp->add(new admin_setting_configtext('maxtimelimit', new lang_string('maxtimelimit', 'admin'),
+        new lang_string('maxtimelimit_desc', 'admin'), 0, PARAM_INT));
 
 $temp->add(new admin_setting_configtext('curlcache', new lang_string('curlcache', 'admin'),
                                         new lang_string('configcurlcache', 'admin'), 120, PARAM_INT));

lang/en/admin.php

@@ -767,6 +767,8 @@ $string['nohttpsformobilewarning'] = 'It is recommended to enable HTTPS with a v
 $string['nomissingstrings'] = 'No missing strings';
 $string['nonewsettings'] = 'No new settings were added during this upgrade.';
 $string['nonexistentbookmark'] = 'The bookmark you requested does not exist.';
+$string['maxtimelimit'] = 'Maximum time limit';
+$string['maxtimelimit_desc'] = 'To restrict the maximum PHP execution time that Moodle will allow without any output being displayed, enter a value in seconds here. 0 means that Moodle default restrictions are used. If you have a front-end server with its own time limit, set this value lower to receive PHP errors in logs. Does not apply to CLI scripts.';
 $string['noresults'] = 'No results found.';
 $string['noroles'] = 'No roles';
 $string['notifications'] = 'Notifications';

lib/classes/php_time_limit.php

+<?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/>.
+
+/**
+ * PHP time limit management.
+ *
+ * @package core
+ * @copyright 2013 The Open University
+ * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+defined('MOODLE_INTERNAL') || die();
+
+/**
+ * Utility class to manage PHP time limit.
+ */
+class core_php_time_limit {
+    /**
+     * @var int Current end time of time limit (-1 if not set)
+     */
+    protected static $currentend = -1;
+
+    /**
+     * @var array Data for unit testing
+     */
+    protected static $unittestdata = array();
+
+    /**
+     * Sets the PHP time limit to a number of seconds from now.
+     *
+     * This function will always extend the time limit (in other words, if the time
+     * limit has already been set further in the future, it will do nothing).
+     *
+     * In order to support front-end servers which may time out silently if no
+     * output is displayed, you should ideally only call this function if you expect
+     * some output to be displayed at the same time. (I.e. if you call this function
+     * each time around a loop, also display some output each time around the loop,
+     * such as a progress bar update.)
+     *
+     * @param int $newlimit Limit in seconds from now (0 = infinite)
+     */
+    public static function raise($newlimit = 0) {
+        global $CFG;
+
+        // Special behaviour in unit tests so that we can check the value.
+        if (PHPUNIT_TEST) {
+            self::$unittestdata[] = $newlimit;
+        }
+
+        // If the time limit has already been set to 'infinite', ignore. Also do
+        // nothing in CLI scripts (including unit testing) which are set to
+        // infinite by default.
+        if (self::$currentend === 0 || CLI_SCRIPT) {
+            return;
+        }
+
+        // Maximum time limit can be set in config. This can be useful for front-end
+        // server systems; if the front-end server has a timeout without receiving
+        // data, it's helpful to set this timeout lower to ensure that a suitable
+        // error gets logged.
+        if ($CFG->maxtimelimit) {
+            $realtimeout = max(1, $CFG->maxtimelimit);
+            if ($newlimit === 0) {
+                $newlimit = $realtimeout;
+            } else {
+                $newlimit = min($newlimit, $realtimeout);
+            }
+        }
+
+        // If new time limit is infinite, just set that.
+        if ($newlimit === 0) {
+            self::$currentend = 0;
+            @set_time_limit(0);
+            return;
+        }
+
+        // Calculate time limits to make sure it's longer than previous.
+        $now = time();
+        $newend = $now + $newlimit;
+        if (self::$currentend !== -1 && self::$currentend > $newend) {
+            // Existing time limit is already longer, so do nothing.
+            return;
+        }
+
+        // Set time limit and update current value.
+        @set_time_limit($newlimit);
+        self::$currentend = $newend;
+    }
+
+    /**
+     * For unit testing, returns an array of the values set during test.
+     *
+     * @return array Array of values set
+     */
+    public static function get_and_clear_unit_test_data() {
+        $data = self::$unittestdata;
+        self::$unittestdata = array();
+        return $data;
+    }
+}