messageTray: Prevent reentrancy issues in _updateState

The methods we call in _updateState may not be reentrant, so make
sure that we never get into a situation where _updateState, through
some crazy chain of events, calls itself.

https://bugzilla.gnome.org/show_bug.cgi?id=711694

diff --git a/js/ui/messageTray.js b/js/ui/messageTray.js
index 2c4f823aa11fbc21eddd4c625dc721c5245804b5..fa24c139f2d8fe8aae6462cb2d12ce7b3672dedd 100644 (file)
--- a/js/ui/messageTray.js
+++ b/js/ui/messageTray.js
@@ -2356,6 +2356,13 @@ const MessageTray = new Lang.Class({
     // _updateState() figures out what (if anything) needs to be done
     // at the present time.
     _updateState: function() {
+        // If our state changes caused _updateState to be called,
+        // just exit now to prevent reentrancy issues.
+        if (this._updatingState)
+            return;
+
+        this._updatingState = true;
+
         // Filter out acknowledged notifications.
         this._notificationQueue = this._notificationQueue.filter(function(n) {
             return !n.acknowledged;
@@ -2436,6 +2443,8 @@ const MessageTray = new Lang.Class({
             this._showDesktopClone();
         else if (desktopCloneIsVisible && !desktopCloneShouldBeVisible)
             this._hideDesktopClone();
+
+        this._updatingState = false;
     },
 
     _tween: function(actor, statevar, value, params) {