From a20ba6a9009d797f5204b0175cf490524cd4fd52 Mon Sep 17 00:00:00 2001
From: Lucas Murray <lmurray@undefinedfire.com>
Date: Thu, 25 Jun 2009 10:09:09 +0000
Subject: [PATCH] Prevent KWin from automatically disabling compositing when
 the user changes the system time or timezone. BUG: 184607

svn path=/trunk/KDE/kdebase/workspace/; revision=986962
---
 composite.cpp | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/composite.cpp b/composite.cpp
index d981f1f00d..04cf62a760 100644
--- a/composite.cpp
+++ b/composite.cpp
@@ -493,6 +493,13 @@ void Workspace::checkCompositePaintTime( int msec )
     {
     if( options->disableCompositingChecks )
         return;
+    // Sanity check. QTime uses the system clock so if the user changes the time or
+    // timezone our timer will return undefined results. Ideally we would use a system
+    // clock independent timer but I am uncertain if Qt provides a nice wrapper for
+    // one or not. As it's unlikely for a single paint to take 15 seconds it seems
+    // like a good upper bound.
+    if( msec < 0 || msec > 15000 )
+        return;
     composite_paint_times.prepend( msec );
     bool tooslow = false;
     // If last 3 paints were way too slow, disable and warn.