} else {
                $errormsg = get_string("invalidlogin");
                $errorcode = 3;
            }
        }
    }
}
/// Detect problems with timedout sessions
if ($session_has_timed_out and !data_submitted()) {
    $errormsg = get_string('sessionerroruser', 'error');
    $errorcode = 4;
}
/// First, let's remember where the user was trying to get to before they got here
if (empty($SESSION->wantsurl)) {
    $SESSION->wantsurl = null;
    $referer = get_local_referer(false);
    if ($referer && $referer != $CFG->wwwroot && $referer != $CFG->wwwroot . '/' && $referer != $CFG->httpswwwroot . '/login/' && strpos($referer, $CFG->httpswwwroot . '/login/?') !== 0 && strpos($referer, $CFG->httpswwwroot . '/login/index.php') !== 0) {
        // There might be some extra params such as ?lang=.
        $SESSION->wantsurl = $referer;
    }
}
/// Redirect to alternative login URL if needed
if (!empty($CFG->alternateloginurl)) {
    $loginurl = $CFG->alternateloginurl;
    if (strpos($SESSION->wantsurl, $loginurl) === 0) {
        //we do not want to return to alternate url
        $SESSION->wantsurl = NULL;
    }
    if ($errorcode) {
        if (strpos($loginurl, '?') === false) {
            $loginurl .= '?';

    $renderer = $PAGE->get_renderer('mod_choice');
    echo $renderer->display_options($options, $cm->id, $choice->display, $choice->allowmultiple);
    $choiceformshown = true;
} else {
    $choiceformshown = false;
}
if (!$choiceformshown) {
    $sitecontext = context_system::instance();
    if (isguestuser()) {
        // Guest account
        echo $OUTPUT->confirm(get_string('noguestchoose', 'choice') . '<br /><br />' . get_string('liketologin'), get_login_url(), new moodle_url('/course/view.php', array('id' => $course->id)));
    } else {
        if (!is_enrolled($context)) {
            // Only people enrolled can make a choice
            $SESSION->wantsurl = qualified_me();
            $SESSION->enrolcancel = get_local_referer(false);
            $coursecontext = context_course::instance($course->id);
            $courseshortname = format_string($course->shortname, true, array('context' => $coursecontext));
            echo $OUTPUT->box_start('generalbox', 'notice');
            echo '<p align="center">' . get_string('notenrolledchoose', 'choice') . '</p>';
            echo $OUTPUT->container_start('continuebutton');
            echo $OUTPUT->single_button(new moodle_url('/enrol/index.php?', array('id' => $course->id)), get_string('enrolme', 'core_enrol', $courseshortname));
            echo $OUTPUT->container_end();
            echo $OUTPUT->box_end();
        }
    }
}
// print the results at the bottom of the screen
if (choice_can_view_results($choice, $current, $choiceopen)) {
    if (!empty($choice->showunanswered)) {
        $choice->option[0] = get_string('notanswered', 'choice');

//.........这里部分代码省略.........
    }
    // Redirect to the login page if session has expired, only with dbsessions enabled (MDL-35029) to maintain current behaviour.
    if ((!isloggedin() or isguestuser()) && !empty($SESSION->has_timed_out) && !empty($CFG->dbsessions)) {
        if ($preventredirect) {
            throw new require_login_session_timeout_exception();
        } else {
            if ($setwantsurltome) {
                $SESSION->wantsurl = qualified_me();
            }
            redirect(get_login_url());
        }
    }
    // If the user is not even logged in yet then make sure they are.
    if (!isloggedin()) {
        if ($autologinguest and !empty($CFG->guestloginbutton) and !empty($CFG->autologinguests)) {
            if (!($guest = get_complete_user_data('id', $CFG->siteguest))) {
                // Misconfigured site guest, just redirect to login page.
                redirect(get_login_url());
                exit;
                // Never reached.
            }
            $lang = isset($SESSION->lang) ? $SESSION->lang : $CFG->lang;
            complete_user_login($guest);
            $USER->autologinguest = true;
            $SESSION->lang = $lang;
        } else {
            // NOTE: $USER->site check was obsoleted by session test cookie, $USER->confirmed test is in login/index.php.
            if ($preventredirect) {
                throw new require_login_exception('You are not logged in');
            }
            if ($setwantsurltome) {
                $SESSION->wantsurl = qualified_me();
            }
            $referer = get_local_referer(false);
            if (!empty($referer)) {
                $SESSION->fromurl = $referer;
            }
            // Give auth plugins an opportunity to authenticate or redirect to an external login page
            $authsequence = get_enabled_auth_plugins(true);
            // auths, in sequence
            foreach ($authsequence as $authname) {
                $authplugin = get_auth_plugin($authname);
                $authplugin->pre_loginpage_hook();
                if (isloggedin()) {
                    break;
                }
            }
            // If we're still not logged in then go to the login page
            if (!isloggedin()) {
                redirect(get_login_url());
                exit;
                // Never reached.
            }
        }
    }
    // Loginas as redirection if needed.
    if ($course->id != SITEID and \core\session\manager::is_loggedinas()) {
        if ($USER->loginascontext->contextlevel == CONTEXT_COURSE) {
            if ($USER->loginascontext->instanceid != $course->id) {
                print_error('loginasonecourse', '', $CFG->wwwroot . '/course/view.php?id=' . $USER->loginascontext->instanceid);
            }
        }
    }
    // Check whether the user should be changing password (but only if it is REALLY them).
    if (get_user_preferences('auth_forcepasswordchange') && !\core\session\manager::is_loggedinas()) {
        $userauth = get_auth_plugin($USER->auth);

/**
 * @global object
 * @global object
 */
function forum_set_return()
{
    global $CFG, $SESSION;
    if (!isset($SESSION->fromdiscussion)) {
        $referer = get_local_referer(false);
        // If the referer is NOT a login screen then save it.
        if (!strncasecmp("{$CFG->wwwroot}/login", $referer, 300)) {
            $SESSION->fromdiscussion = $referer;
        }
    }
}

 /**
  * Will get called before the login page is shownr. Ff NTLM SSO
  * is enabled, and the user is in the right network, we'll redirect
  * to the magic NTLM page for SSO...
  *
  */
 function loginpage_hook()
 {
     global $CFG, $SESSION;
     // HTTPS is potentially required
     //httpsrequired(); - this must be used before setting the URL, it is already done on the login/index.php
     if (($_SERVER['REQUEST_METHOD'] === 'GET' || $_SERVER['REQUEST_METHOD'] === 'POST' && get_local_referer() != strip_querystring(qualified_me())) && !empty($this->config->ntlmsso_enabled) && !empty($this->config->ntlmsso_subnet) && empty($_GET['authldap_skipntlmsso']) && (isguestuser() || !isloggedin()) && address_in_subnet(getremoteaddr(), $this->config->ntlmsso_subnet)) {
         // First, let's remember where we were trying to get to before we got here
         if (empty($SESSION->wantsurl)) {
             $SESSION->wantsurl = null;
             $referer = get_local_referer(false);
             if ($referer && $referer != $CFG->wwwroot && $referer != $CFG->wwwroot . '/' && $referer != $CFG->httpswwwroot . '/login/' && $referer != $CFG->httpswwwroot . '/login/index.php') {
                 $SESSION->wantsurl = $referer;
             }
         }
         // Now start the whole NTLM machinery.
         if ($this->config->ntlmsso_ie_fastpath == AUTH_NTLM_FASTPATH_YESATTEMPT || $this->config->ntlmsso_ie_fastpath == AUTH_NTLM_FASTPATH_YESFORM) {
             if (core_useragent::is_ie()) {
                 $sesskey = sesskey();
                 redirect($CFG->wwwroot . '/auth/ldap/ntlmsso_magic.php?sesskey=' . $sesskey);
             } else {
                 if ($this->config->ntlmsso_ie_fastpath == AUTH_NTLM_FASTPATH_YESFORM) {
                     redirect($CFG->httpswwwroot . '/login/index.php?authldap_skipntlmsso=1');
                 }
             }
         }
         redirect($CFG->wwwroot . '/auth/ldap/ntlmsso_attempt.php');
     }
     // No NTLM SSO, Use the normal login page instead.
     // If $SESSION->wantsurl is empty and we have a 'Referer:' header, the login
     // page insists on redirecting us to that page after user validation. If
     // we clicked on the redirect link at the ntlmsso_finish.php page (instead
     // of waiting for the redirection to happen) then we have a 'Referer:' header
     // we don't want to use at all. As we can't get rid of it, just point
     // $SESSION->wantsurl to $CFG->wwwroot (after all, we came from there).
     if (empty($SESSION->wantsurl) && get_local_referer() == $CFG->httpswwwroot . '/auth/ldap/ntlmsso_finish.php') {
         $SESSION->wantsurl = $CFG->wwwroot;
     }
 }

if (!($cm = get_coursemodule_from_instance("forum", $forum->id, $course->id))) {
    print_error('invalidcoursemodule');
}
require_login($course, false, $cm);
$returnpageurl = new moodle_url('/mod/forum/' . $returnpage, array('id' => $course->id, 'f' => $forum->id));
$returnto = forum_go_back_to($returnpageurl);
if (!forum_tp_can_track_forums($forum)) {
    redirect($returnto);
}
$info = new stdClass();
$info->name = fullname($USER);
$info->forum = format_string($forum->name);
$eventparams = array('context' => context_module::instance($cm->id), 'relateduserid' => $USER->id, 'other' => array('forumid' => $forum->id));
if (forum_tp_is_tracked($forum)) {
    if (forum_tp_stop_tracking($forum->id)) {
        $event = \mod_forum\event\readtracking_disabled::create($eventparams);
        $event->trigger();
        redirect($returnto, get_string("nownottracking", "forum", $info), 1);
    } else {
        print_error('cannottrack', '', get_local_referer(false));
    }
} else {
    // subscribe
    if (forum_tp_start_tracking($forum->id)) {
        $event = \mod_forum\event\readtracking_enabled::create($eventparams);
        $event->trigger();
        redirect($returnto, get_string("nowtracking", "forum", $info), 1);
    } else {
        print_error('cannottrack', '', get_local_referer(false));
    }
}

//.........这里部分代码省略.........
         // Verify timeout first.
         $maxlifetime = $CFG->sessiontimeout;
         $timeout = false;
         if (isguestuser($userid) or empty($userid)) {
             // Ignore guest and not-logged in timeouts, there is very little risk here.
             $timeout = false;
         } else {
             if ($record->timemodified < time() - $maxlifetime) {
                 $timeout = true;
                 $authsequence = get_enabled_auth_plugins();
                 // Auths, in sequence.
                 foreach ($authsequence as $authname) {
                     $authplugin = get_auth_plugin($authname);
                     if ($authplugin->ignore_timeout_hook($_SESSION['USER'], $record->sid, $record->timecreated, $record->timemodified)) {
                         $timeout = false;
                         break;
                     }
                 }
             }
         }
         if ($timeout) {
             session_regenerate_id(true);
             $_SESSION = array();
             $DB->delete_records('sessions', array('id' => $record->id));
         } else {
             // Update session tracking record.
             $update = new \stdClass();
             $updated = false;
             if ($record->userid != $userid) {
                 $update->userid = $record->userid = $userid;
                 $updated = true;
             }
             $ip = getremoteaddr();
             if ($record->lastip != $ip) {
                 $update->lastip = $record->lastip = $ip;
                 $updated = true;
             }
             $updatefreq = empty($CFG->session_update_timemodified_frequency) ? 20 : $CFG->session_update_timemodified_frequency;
             if ($record->timemodified == $record->timecreated) {
                 // Always do first update of existing record.
                 $update->timemodified = $record->timemodified = time();
                 $updated = true;
             } else {
                 if ($record->timemodified < time() - $updatefreq) {
                     // Update the session modified flag only once every 20 seconds.
                     $update->timemodified = $record->timemodified = time();
                     $updated = true;
                 }
             }
             if ($updated) {
                 $update->id = $record->id;
                 $DB->update_record('sessions', $update);
             }
             return;
         }
     } else {
         if ($record) {
             // This happens when people switch session handlers...
             session_regenerate_id(true);
             $_SESSION = array();
             $DB->delete_records('sessions', array('id' => $record->id));
         }
     }
     unset($record);
     $timedout = false;
     if (!isset($_SESSION['SESSION'])) {
         $_SESSION['SESSION'] = new \stdClass();
         if (!$newsid) {
             $timedout = true;
         }
     }
     $user = null;
     if (!empty($CFG->opentogoogle)) {
         if (\core_useragent::is_web_crawler()) {
             $user = guest_user();
         }
         $referer = get_local_referer(false);
         if (!empty($CFG->guestloginbutton) and !$user and !empty($referer)) {
             // Automatically log in users coming from search engine results.
             if (strpos($referer, 'google') !== false) {
                 $user = guest_user();
             } else {
                 if (strpos($referer, 'altavista') !== false) {
                     $user = guest_user();
                 }
             }
         }
     }
     // Setup $USER and insert the session tracking record.
     if ($user) {
         self::set_user($user);
         self::add_session_record($user->id);
     } else {
         self::init_empty_session();
         self::add_session_record(0);
     }
     if ($timedout) {
         $_SESSION['SESSION']->has_timed_out = true;
     }
 }

 /**
  * Outputs an error message for any guests accessing the quiz
  *
  * @param int $course The course ID
  * @param array $quiz Array contingin quiz data
  * @param int $cm Course Module ID
  * @param int $context The page contect ID
  * @param array $messages Array containing any messages
  */
 public function view_page_guest($course, $quiz, $cm, $context, $messages)
 {
     $output = '';
     $output .= $this->view_information($quiz, $cm, $context, $messages);
     $guestno = html_writer::tag('p', get_string('guestsno', 'quiz'));
     $liketologin = html_writer::tag('p', get_string('liketologin'));
     $referer = get_local_referer(false);
     $output .= $this->confirm($guestno . "\n\n" . $liketologin . "\n", get_login_url(), $referer);
     return $output;
 }

        }
    } else {
        if (\mod_twf\subscriptions::unsubscribe_user_from_discussion($user->id, $discussion, $context)) {
            $info->discussion = $discussion->name;
            redirect($returnto, get_string("discussionnownotsubscribed", "twf", $info), 1);
        } else {
            print_error('cannotunsubscribe', 'twf', get_local_referer(false));
        }
    }
} else {
    // subscribe
    if (\mod_twf\subscriptions::subscription_disabled($twf) && !has_capability('mod/twf:managesubscriptions', $context)) {
        print_error('disallowsubscribe', 'twf', get_local_referer(false));
    }
    if (!has_capability('mod/twf:viewdiscussion', $context)) {
        print_error('noviewdiscussionspermission', 'twf', get_local_referer(false));
    }
    if (is_null($sesskey)) {
        // We came here via link in email.
        $PAGE->set_title($course->shortname);
        $PAGE->set_heading($course->fullname);
        echo $OUTPUT->header();
        $viewurl = new moodle_url('/mod/twf/view.php', array('f' => $id));
        if ($discussionid) {
            $a = new stdClass();
            $a->twf = format_string($twf->name);
            $a->discussion = format_string($discussion->name);
            echo $OUTPUT->confirm(get_string('confirmsubscribediscussion', 'twf', $a), $PAGE->url, $viewurl);
        } else {
            echo $OUTPUT->confirm(get_string('confirmsubscribe', 'twf', format_string($twf->name)), $PAGE->url, $viewurl);
        }

    }
    redirect($destination);
    // Bye!
}
$PAGE->set_title($course->shortname);
$PAGE->set_heading($course->fullname);
$PAGE->navbar->add(get_string('enrolmentoptions', 'enrol'));
echo $OUTPUT->header();
echo $OUTPUT->heading(get_string('enrolmentoptions', 'enrol'));
$courserenderer = $PAGE->get_renderer('core', 'course');
echo $courserenderer->course_info_box($course);
//TODO: find if future enrolments present and display some info
foreach ($forms as $form) {
    echo $form;
}
if (!$forms) {
    if (isguestuser()) {
        notice(get_string('noguestaccess', 'enrol'), get_login_url());
    } else {
        if ($returnurl) {
            notice(get_string('notenrollable', 'enrol'), $returnurl);
        } else {
            $url = get_local_referer(false);
            if (empty($url)) {
                $url = new moodle_url('/index.php');
            }
            notice(get_string('notenrollable', 'enrol'), $url);
        }
    }
}
echo $OUTPUT->footer();

    print_error('coursemisconf');
}
$PAGE->set_url('/mod/survey/save.php', array('id' => $id));
require_login($course, false, $cm);
$context = context_module::instance($cm->id);
require_capability('mod/survey:participate', $context);
if (!($survey = $DB->get_record("survey", array("id" => $cm->instance)))) {
    print_error('invalidsurveyid', 'survey');
}
$strsurveysaved = get_string('surveysaved', 'survey');
$PAGE->set_title($strsurveysaved);
$PAGE->set_heading($course->fullname);
echo $OUTPUT->header();
echo $OUTPUT->heading($survey->name);
if (survey_already_done($survey->id, $USER->id)) {
    notice(get_string("alreadysubmitted", "survey"), get_local_referer(false));
    exit;
}
// Sort through the data and arrange it
// This is necessary because some of the questions
// may have two answers, eg Question 1 -> 1 and P1
$answers = array();
foreach ($formdata as $key => $val) {
    if ($key != "userid" && $key != "id") {
        if (substr($key, 0, 1) == "q") {
            $key = clean_param(substr($key, 1), PARAM_ALPHANUM);
            // keep everything but the 'q', number or Pnumber
        }
        if (substr($key, 0, 1) == "P") {
            $realkey = (int) substr($key, 1);
            $answers[$realkey][1] = $val;

 public function view()
 {
     global $OUTPUT, $CFG;
     if (!$this->items && $this->canedit()) {
         redirect(new moodle_url('/mod/checklist/edit.php', array('id' => $this->cm->id)));
     }
     if ($this->canupdateown()) {
         $currenttab = 'view';
     } else {
         if ($this->canpreview()) {
             $currenttab = 'preview';
         } else {
             if ($this->canviewreports()) {
                 // No editing, but can view reports.
                 redirect(new moodle_url('/mod/checklist/report.php', array('id' => $this->cm->id)));
             } else {
                 $this->view_header();
                 if ($CFG->branch >= 30) {
                     $ref = get_local_referer(false);
                 } else {
                     $ref = get_referer(false);
                 }
                 echo $OUTPUT->heading(format_string($this->checklist->name));
                 echo $OUTPUT->confirm('<p>' . get_string('guestsno', 'checklist') . "</p>\n\n<p>" . get_string('liketologin') . "</p>\n", get_login_url(), $ref);
                 echo $OUTPUT->footer();
                 die;
             }
             $currenttab = '';
         }
     }
     $this->view_header();
     echo $OUTPUT->heading(format_string($this->checklist->name));
     $this->view_tabs($currenttab);
     if ($CFG->version > 2014051200) {
         // Moodle 2.7+.
         $params = array('contextid' => $this->context->id, 'objectid' => $this->checklist->id);
         $event = \mod_checklist\event\course_module_viewed::create($params);
         $event->trigger();
     } else {
         // Before Moodle 2.7.
         add_to_log($this->course->id, 'checklist', 'view', "view.php?id={$this->cm->id}", $this->checklist->id, $this->cm->id);
     }
     if ($this->canupdateown()) {
         $this->process_view_actions();
     }
     $this->view_items();
     $this->view_footer();
 }

                                $questionnaire->page->add_to_page('message', get_string('noneinuse', 'questionnaire'));
                            }
                        }
                    }
                }
            }
        }
    }
}
if ($questionnaire->capabilities->editquestions && !$questionnaire->questions && $questionnaire->is_active()) {
    $questionnaire->page->add_to_page('complete', '<a href="' . $CFG->wwwroot . htmlspecialchars('/mod/questionnaire/questions.php?' . 'id=' . $questionnaire->cm->id) . '">' . '<strong>' . get_string('addquestions', 'questionnaire') . '</strong></a>');
}
if (isguestuser()) {
    $guestno = html_writer::tag('p', get_string('noteligible', 'questionnaire'));
    $liketologin = html_writer::tag('p', get_string('liketologin'));
    $questionnaire->page->add_to_page('guestuser', $questionnaire->renderer->confirm($guestno . "\n\n" . $liketologin . "\n", get_login_url(), get_local_referer(false)));
}
// Log this course module view.
// Needed for the event logging.
$context = context_module::instance($questionnaire->cm->id);
$anonymous = $questionnaire->respondenttype == 'anonymous';
$event = \mod_questionnaire\event\course_module_viewed::create(array('objectid' => $questionnaire->id, 'anonymous' => $anonymous, 'context' => $context));
$event->trigger();
$usernumresp = $questionnaire->count_submissions($USER->id);
if ($questionnaire->capabilities->readownresponses && $usernumresp > 0) {
    $argstr = 'instance=' . $questionnaire->id . '&user=' . $USER->id;
    if ($usernumresp > 1) {
        $titletext = get_string('viewyourresponses', 'questionnaire', $usernumresp);
    } else {
        $titletext = get_string('yourresponse', 'questionnaire');
        $argstr .= '&byresponse=1&action=vresp';

$files = $fs->get_area_files($context->id, 'mod_resource', 'content', 0, 'sortorder DESC, id ASC', false);
// TODO: this is not very efficient!!
if (count($files) < 1) {
    resource_print_filenotfound($resource, $cm, $course);
    die;
} else {
    $file = reset($files);
    unset($files);
}
$resource->mainfile = $file->get_filename();
$displaytype = resource_get_final_display_type($resource);
if ($displaytype == RESOURCELIB_DISPLAY_OPEN || $displaytype == RESOURCELIB_DISPLAY_DOWNLOAD) {
    // For 'open' and 'download' links, we always redirect to the content - except
    // if the user just chose 'save and display' from the form then that would be
    // confusing
    if (strpos(get_local_referer(false), 'modedit.php') === false) {
        $redirect = true;
    }
}
// Don't redirect teachers, otherwise they can not access course or module settings.
if ($redirect && !course_get_format($course)->has_view_page() && (has_capability('moodle/course:manageactivities', $context) || has_capability('moodle/course:update', context_course::instance($course->id)))) {
    $redirect = false;
}
if ($redirect) {
    // coming from course page or url index page
    // this redirect trick solves caching problems when tracking views ;-)
    $path = '/' . $context->id . '/mod_resource/content/' . $resource->revision . $file->get_filepath() . $file->get_filename();
    $fullurl = moodle_url::make_file_url('/pluginfile.php', $path, $displaytype == RESOURCELIB_DISPLAY_DOWNLOAD);
    redirect($fullurl);
}
switch ($displaytype) {

        }
    }
}
if ($questionnaire->is_active() && !$questionnaire->questions) {
    echo '<p>' . get_string('noneinuse', 'questionnaire') . '</p>';
}
if ($questionnaire->is_active() && $questionnaire->capabilities->editquestions && !$questionnaire->questions) {
    // Sanity check.
    echo '<a href="' . $CFG->wwwroot . htmlspecialchars('/mod/questionnaire/questions.php?' . 'id=' . $questionnaire->cm->id) . '">' . '<strong>' . get_string('addquestions', 'questionnaire') . '</strong></a>';
}
echo $OUTPUT->box_end();
if (isguestuser()) {
    $output = '';
    $guestno = html_writer::tag('p', get_string('noteligible', 'questionnaire'));
    $liketologin = html_writer::tag('p', get_string('liketologin'));
    $output .= $OUTPUT->confirm($guestno . "\n\n" . $liketologin . "\n", get_login_url(), get_local_referer(false));
    echo $output;
}
// Log this course module view.
// Needed for the event logging.
$context = context_module::instance($questionnaire->cm->id);
$anonymous = $questionnaire->respondenttype == 'anonymous';
$event = \mod_questionnaire\event\course_module_viewed::create(array('objectid' => $questionnaire->id, 'anonymous' => $anonymous, 'context' => $context));
$event->trigger();
$usernumresp = $questionnaire->count_submissions($USER->id);
if ($questionnaire->capabilities->readownresponses && $usernumresp > 0) {
    echo $OUTPUT->box_start('generalbox boxaligncenter boxwidthwide');
    $argstr = 'instance=' . $questionnaire->id . '&user=' . $USER->id;
    if ($usernumresp > 1) {
        $titletext = get_string('viewyourresponses', 'questionnaire', $usernumresp);
    } else {