if (get_string_manager()->translation_exists($lang, false)) {
        $SESSION->lang = $lang;
    }
}
unset($lang);
setup_lang_from_browser();
if (empty($CFG->lang)) {
    if (empty($SESSION->lang)) {
        $CFG->lang = 'en';
    } else {
        $CFG->lang = $SESSION->lang;
    }
}
// Set the default site locale, a lot of the stuff may depend on this
// it is definitely too late to call this first in require_login()!
moodle_setlocale();
if (!empty($CFG->debugvalidators) and !empty($CFG->guestloginbutton)) {
    if ($CFG->theme == 'standard' or $CFG->theme == 'standardwhite') {
        // Temporary measure to help with XHTML validation
        if (isset($_SERVER['HTTP_USER_AGENT']) and empty($USER->id)) {
            // Allow W3CValidator in as user called w3cvalidator (or guest)
            if (strpos($_SERVER['HTTP_USER_AGENT'], 'W3C_Validator') !== false or strpos($_SERVER['HTTP_USER_AGENT'], 'Cynthia') !== false) {
                if ($user = get_complete_user_data("username", "w3cvalidator")) {
                    $user->ignoresesskey = true;
                } else {
                    $user = guest_user();
                }
                session_set_user($user);
            }
        }
    }

 /**
  * Set the current course. This sets both $PAGE->course and $COURSE. It also
  * sets the right theme and locale.
  *
  * Normally you don't need to call this function yourself, require_login will
  * call it for you if you pass a $course to it. You can use this function
  * on pages that do need to call require_login().
  *
  * Sets $PAGE->context to the course context, if it is not already set.
  *
  * @param stdClass $course the course to set as the global course.
  * @throws coding_exception
  */
 public function set_course($course)
 {
     global $COURSE, $PAGE, $CFG, $SITE;
     if (empty($course->id)) {
         throw new coding_exception('$course passed to moodle_page::set_course does not look like a proper course object.');
     }
     $this->ensure_theme_not_set();
     if (!empty($this->_course->id) && $this->_course->id != $course->id) {
         $this->_categories = null;
     }
     $this->_course = clone $course;
     if ($this === $PAGE) {
         $COURSE = $this->_course;
         moodle_setlocale();
     }
     if (!$this->_context) {
         $this->set_context(context_course::instance($this->_course->id));
     }
     // Notify course format that this page is set for the course.
     if ($this->_course->id != $SITE->id) {
         require_once $CFG->dirroot . '/course/lib.php';
         $courseformat = course_get_format($this->_course);
         $this->add_body_class('format-' . $courseformat->get_format());
         $courseformat->page_set_course($this);
     } else {
         $this->add_body_class('format-site');
     }
 }

    /**
     * Set the current course. This sets both $PAGE->course and $COURSE. It also
     * sets the right theme and locale.
     *
     * Normally you don't need to call this function yourself, require_login will
     * call it for you if you pass a $course to it. You can use this function
     * on pages that do need to call require_login().
     *
     * Sets $PAGE->context to the course context, if it is not already set.
     *
     * @param object the course to set as the global course.
     */
    public function set_course($course) {
        global $COURSE, $PAGE;

        if (empty($course->id)) {
            throw new coding_exception('$course passed to moodle_page::set_course does not look like a proper course object.');
        }

        $this->ensure_theme_not_set();

        if (!empty($this->_course->id) && $this->_course->id != $course->id) {
            $this->_categories = null;
        }

        $this->_course = clone($course);

        if ($this === $PAGE) {
            $COURSE = $this->_course;
            moodle_setlocale();
        }

        if (!$this->_context) {
            $this->set_context(get_context_instance(CONTEXT_COURSE, $this->_course->id));
        }
    }

function report_session_error()
{
    global $CFG, $FULLME;
    if (empty($CFG->lang)) {
        $CFG->lang = "en";
    }
    // Set up default theme and locale
    theme_setup();
    moodle_setlocale();
    //clear session cookies
    if (check_php_version('5.2.0')) {
        //PHP 5.2.0
        setcookie('MoodleSession' . $CFG->sessioncookie, '', time() - 3600, $CFG->sessioncookiepath, $CFG->sessioncookiedomain, $CFG->cookiesecure, $CFG->cookiehttponly);
        setcookie('MoodleSessionTest' . $CFG->sessioncookie, '', time() - 3600, $CFG->sessioncookiepath, $CFG->sessioncookiedomain, $CFG->cookiesecure, $CFG->cookiehttponly);
    } else {
        setcookie('MoodleSession' . $CFG->sessioncookie, '', time() - 3600, $CFG->sessioncookiepath, $CFG->sessioncookiedomain, $CFG->cookiesecure);
        setcookie('MoodleSessionTest' . $CFG->sessioncookie, '', time() - 3600, $CFG->sessioncookiepath, $CFG->sessioncookiedomain, $CFG->cookiesecure);
    }
    //increment database error counters
    if (isset($CFG->session_error_counter)) {
        set_config('session_error_counter', 1 + $CFG->session_error_counter);
    } else {
        set_config('session_error_counter', 1);
    }
    redirect($FULLME, get_string('sessionerroruser2', 'error'), 5);
}

/**
 * Force the current language to get strings and dates localised in the given language.
 *
 * After calling this function, all strings will be provided in the given language
 * until this function is called again, or equivalent code is run.
 *
 * @param string $language
 * @return string previous $SESSION->forcelang value
 */
function force_current_language($language)
{
    global $SESSION;
    $sessionforcelang = isset($SESSION->forcelang) ? $SESSION->forcelang : '';
    if ($language !== $sessionforcelang) {
        // Seting forcelang to null or an empty string disables it's effect.
        if (empty($language) || get_string_manager()->translation_exists($language, false)) {
            $SESSION->forcelang = $language;
            moodle_setlocale();
        }
    }
    return $sessionforcelang;
}

 /**
  * Notify person responsible for enrolments that some user enrolments will be expired soon,
  * it is called only if notification of enrollers (aka teachers) is enabled in course.
  *
  * This is called repeatedly every day for each course if there are any pending expiration
  * in the expiration threshold.
  *
  * @param int $eid
  * @param array $users
  * @param bool $verbose
  */
 protected function notify_expiry_enroller($eid, $users, $verbose)
 {
     global $DB, $SESSION;
     $name = $this->get_name();
     $instance = $DB->get_record('enrol', array('id' => $eid, 'enrol' => $name));
     $context = context_course::instance($instance->courseid);
     $course = $DB->get_record('course', array('id' => $instance->courseid));
     $enroller = $this->get_enroller($instance->id);
     $admin = get_admin();
     // Some nasty hackery to get strings and dates localised for target user.
     $sessionlang = isset($SESSION->lang) ? $SESSION->lang : null;
     if (get_string_manager()->translation_exists($enroller->lang, false)) {
         $SESSION->lang = $enroller->lang;
         moodle_setlocale();
     }
     foreach ($users as $key => $info) {
         $users[$key] = '* ' . $info['fullname'] . ' - ' . userdate($info['timeend'], '', $enroller->timezone);
     }
     $a = new stdClass();
     $a->course = format_string($course->fullname, true, array('context' => $context));
     $a->threshold = get_string('numdays', '', $instance->expirythreshold / (60 * 60 * 24));
     $a->users = implode("\n", $users);
     $a->extendurl = (string) new moodle_url('/enrol/users.php', array('id' => $instance->courseid));
     $subject = get_string('expirymessageenrollersubject', 'enrol_' . $name, $a);
     $body = get_string('expirymessageenrollerbody', 'enrol_' . $name, $a);
     $message = new stdClass();
     $message->notification = 1;
     $message->component = 'enrol_' . $name;
     $message->name = 'expiry_notification';
     $message->userfrom = $admin;
     $message->userto = $enroller;
     $message->subject = $subject;
     $message->fullmessage = $body;
     $message->fullmessageformat = FORMAT_MARKDOWN;
     $message->fullmessagehtml = markdown_to_html($body);
     $message->smallmessage = $subject;
     $message->contexturlname = $a->course;
     $message->contexturl = $a->extendurl;
     if (message_send($message)) {
         if ($verbose) {
             mtrace("  notifying user {$enroller->id} about all expiring {$name} enrolments in course {$instance->courseid}");
         }
     } else {
         if ($verbose) {
             mtrace("  error notifying user {$enroller->id} about all expiring {$name} enrolments in course {$instance->courseid}");
         }
     }
     if ($SESSION->lang !== $sessionlang) {
         $SESSION->lang = $sessionlang;
         moodle_setlocale();
     }
 }

function dimdim_force_language($lang)
{
    /// This function prepares moodle to operate in given language
    /// usable when $nomoodlecookie = true;
    /// BEWARE: there must be no $course, $USER or $SESSION
    global $CFG;
    if (!empty($CFG->courselang)) {
        unset($CFG->courselang);
    }
    if (!empty($CFG->locale)) {
        unset($CFG->locale);
    }
    $CFG->lang = $lang;
    moodle_setlocale();
}

 /**
  * Process user enrolment line.
  *
  * @param progress_trace $trace
  * @param string $action
  * @param int $roleid
  * @param stdClass $user
  * @param stdClass $course
  * @param int $timestart
  * @param int $timeend
  * @param bool $buffer_if_future
  */
 protected function process_records(progress_trace $trace, $action, $roleid, $user, $course, $timestart, $timeend, $buffer_if_future = true)
 {
     global $CFG, $DB, $SESSION;
     // Check if timestart is for future processing.
     if ($timestart > time() and $buffer_if_future) {
         // Populate into enrol_flatfile table as a future role to be assigned by cron.
         // Note: since 2.0 future enrolments do not cause problems if you disable guest access.
         $future_en = new stdClass();
         $future_en->action = $action;
         $future_en->roleid = $roleid;
         $future_en->userid = $user->id;
         $future_en->courseid = $course->id;
         $future_en->timestart = $timestart;
         $future_en->timeend = $timeend;
         $future_en->timemodified = time();
         $DB->insert_record('enrol_flatfile', $future_en);
         $trace->output("User {$user->id} will be enrolled later into course {$course->id} using role {$roleid} ({$timestart}, {$timeend})", 1);
         return;
     }
     $context = context_course::instance($course->id);
     if ($action === 'add') {
         // Clear the buffer just in case there were some future enrolments.
         $DB->delete_records('enrol_flatfile', array('userid' => $user->id, 'courseid' => $course->id, 'roleid' => $roleid));
         $instance = $DB->get_record('enrol', array('courseid' => $course->id, 'enrol' => 'flatfile'));
         if (empty($instance)) {
             // Only add an enrol instance to the course if non-existent.
             $enrolid = $this->add_instance($course);
             $instance = $DB->get_record('enrol', array('id' => $enrolid));
         }
         $notify = false;
         if ($ue = $DB->get_record('user_enrolments', array('enrolid' => $instance->id, 'userid' => $user->id))) {
             // Update only.
             $this->update_user_enrol($instance, $user->id, ENROL_USER_ACTIVE, $roleid, $timestart, $timeend);
             if (!$DB->record_exists('role_assignments', array('contextid' => $context->id, 'roleid' => $roleid, 'userid' => $user->id, 'component' => 'enrol_flatfile', 'itemid' => $instance->id))) {
                 role_assign($roleid, $user->id, $context->id, 'enrol_flatfile', $instance->id);
             }
             $trace->output("User {$user->id} enrolment updated in course {$course->id} using role {$roleid} ({$timestart}, {$timeend})", 1);
         } else {
             // Enrol the user with this plugin instance.
             $this->enrol_user($instance, $user->id, $roleid, $timestart, $timeend);
             $trace->output("User {$user->id} enrolled in course {$course->id} using role {$roleid} ({$timestart}, {$timeend})", 1);
             $notify = true;
         }
         if ($notify and $this->get_config('mailstudents')) {
             // Some nasty hackery to get strings and dates localised for target user.
             $sessionlang = isset($SESSION->lang) ? $SESSION->lang : null;
             if (get_string_manager()->translation_exists($user->lang, false)) {
                 $SESSION->lang = $user->lang;
                 moodle_setlocale();
             }
             // Send welcome notification to enrolled users.
             $a = new stdClass();
             $a->coursename = format_string($course->fullname, true, array('context' => $context));
             $a->profileurl = "{$CFG->wwwroot}/user/view.php?id={$user->id}&course={$course->id}";
             $subject = get_string('enrolmentnew', 'enrol', format_string($course->shortname, true, array('context' => $context)));
             $eventdata = new stdClass();
             $eventdata->modulename = 'moodle';
             $eventdata->component = 'enrol_flatfile';
             $eventdata->name = 'flatfile_enrolment';
             $eventdata->userfrom = $this->get_enroller($course->id);
             $eventdata->userto = $user;
             $eventdata->subject = $subject;
             $eventdata->fullmessage = get_string('welcometocoursetext', '', $a);
             $eventdata->fullmessageformat = FORMAT_PLAIN;
             $eventdata->fullmessagehtml = '';
             $eventdata->smallmessage = '';
             if (message_send($eventdata)) {
                 $trace->output("Notified enrolled user", 1);
             } else {
                 $trace->output("Failed to notify enrolled user", 1);
             }
             if ($SESSION->lang !== $sessionlang) {
                 $SESSION->lang = $sessionlang;
                 moodle_setlocale();
             }
         }
         if ($notify and $this->get_config('mailteachers', 0)) {
             // Notify person responsible for enrolments.
             $enroller = $this->get_enroller($course->id);
             // Some nasty hackery to get strings and dates localised for target user.
             $sessionlang = isset($SESSION->lang) ? $SESSION->lang : null;
             if (get_string_manager()->translation_exists($enroller->lang, false)) {
                 $SESSION->lang = $enroller->lang;
                 moodle_setlocale();
             }
             $a = new stdClass();
             $a->course = format_string($course->fullname, true, array('context' => $context));
             $a->user = fullname($user);
//.........这里部分代码省略.........

/**
 * Lockout user and send notification email.
 *
 * @param stdClass $user
 */
function login_lock_account($user)
{
    global $CFG, $SESSION;
    if ($user->mnethostid != $CFG->mnet_localhost_id) {
        return;
    }
    if (isguestuser($user)) {
        return;
    }
    if (get_user_preferences('login_lockout_ignored', 0, $user)) {
        // This user can not be locked out.
        return;
    }
    $alreadylockedout = get_user_preferences('login_lockout', 0, $user);
    set_user_preference('login_lockout', time(), $user);
    if ($alreadylockedout == 0) {
        $secret = random_string(15);
        set_user_preference('login_lockout_secret', $secret, $user);
        // Some nasty hackery to get strings and dates localised for target user.
        $sessionlang = isset($SESSION->lang) ? $SESSION->lang : null;
        if (get_string_manager()->translation_exists($user->lang, false)) {
            $SESSION->lang = $user->lang;
            moodle_setlocale();
        }
        $site = get_site();
        $supportuser = core_user::get_support_user();
        $data = new stdClass();
        $data->firstname = $user->firstname;
        $data->lastname = $user->lastname;
        $data->username = $user->username;
        $data->sitename = format_string($site->fullname);
        $data->link = $CFG->wwwroot . '/login/unlock_account.php?u=' . $user->id . '&s=' . $secret;
        $data->admin = generate_email_signoff();
        $message = get_string('lockoutemailbody', 'admin', $data);
        $subject = get_string('lockoutemailsubject', 'admin', format_string($site->fullname));
        if ($message) {
            // Directly email rather than using the messaging system to ensure its not routed to a popup or jabber.
            email_to_user($user, $supportuser, $subject, $message);
        }
        if ($SESSION->lang !== $sessionlang) {
            $SESSION->lang = $sessionlang;
            moodle_setlocale();
        }
    }
}

 /**
  * This method is called when the page first moves out of the STATE_BEFORE_HEADER
  * state. This is our last change to initialise things.
  */
 protected function starting_output()
 {
     global $SITE, $CFG;
     if (empty($CFG->rolesactive)) {
         $this->_course = new stdClass();
         $this->_course->id = 1;
         moodle_setlocale();
         theme_setup();
         return;
     }
     if (!$this->_course) {
         $this->set_course($SITE);
     }
     $this->initialise_standard_body_classes();
     $this->blocks->load_blocks();
 }