Merge branch 'wip-mdl-55466' of https://github.com/rajeshtaneja/moodle

lib/upgrade.txt

@@ -73,6 +73,11 @@ information provided here is intended especially for developers.
 * data-fieldtype="type" attribute has been added to form field default template.
 * form elements extending MoodleQuickForm_group must call $this->createFormElement() instead of
   @MoodleQuickForm::createElement() in order to be compatible with PHP 7.1
+* Relative paths in $CFG->alternateloginurl will be resolved to absolute path within moodle site. Previously they
+  were resolved to absolute path within the server. That means:
+  - $CFG->wwwroot: http://example.com/moodle
+  - $CFG->alternateloginurl : /my/super/login.php
+  - Login url will be: http://example.com/moodle/my/super/login.php (moodle root based)
 
 === 3.1 ===
 

login/index.php

@@ -282,23 +282,21 @@ if (empty($SESSION->wantsurl)) {
 
 /// Redirect to alternative login URL if needed
 if (!empty($CFG->alternateloginurl)) {
-    $loginurl = $CFG->alternateloginurl;
+    $loginurl = new moodle_url($CFG->alternateloginurl);
 
-    if (strpos($SESSION->wantsurl, $loginurl) === 0) {
-        //we do not want to return to alternate url
-        $SESSION->wantsurl = NULL;
+    $loginurlstr = $loginurl->out(false);
+
+    if (strpos($SESSION->wantsurl, $loginurlstr) === 0) {
+        // We do not want to return to alternate url.
+        $SESSION->wantsurl = null;
     }
 
+    // If error code then add that to url.
     if ($errorcode) {
-        if (strpos($loginurl, '?') === false) {
-            $loginurl .= '?';
-        } else {
-            $loginurl .= '&';
-        }
-        $loginurl .= 'errorcode='.$errorcode;
+        $loginurl->param('errorcode', $errorcode);
     }
 
-    redirect($loginurl);
+    redirect($loginurl->out(false));
 }
 
 // make sure we really are on the https page when https login required