Workaround for race condition when compositor is animating

If the compositor is animating, and rendering in another thread, we
may get a frameFinished call for a buffer that has not been displayed
yet. This buffer would then never get released, and the client would
hang. This is just a workaround: the real solution would fix the
race condition between markSurfaceAsDirty() and emit damaged().

Also fix misplaced paranthesis.

Change-Id: Iadecc77a6c6e3999a9f07815db0d0f810d92c1d3
Sanity-Review: Qt Sanity Bot <qt_sanity_bot@ovi.com>
Reviewed-by: Jørgen Lind <jorgen.lind@nokia.com>

1 files changed, 6 insertions, 1 deletions

diff --git a/src/compositor/wayland_wrapper/wlsurface.cpp b/src/compositor/wayland_wrapper/wlsurface.cpp
index c23dc2150..86ae1e973 100644
--- a/src/compositor/wayland_wrapper/wlsurface.cpp
+++ b/src/compositor/wayland_wrapper/wlsurface.cpp
@@ -268,6 +268,11 @@ public:
         if (surfaceBuffer && surfaceBuffer->isPosted())
             surfaceBuffer->destructBufferState();
 
+        if (surfaceBuffer && !surfaceBuffer->isDisplayed()) {
+            qDebug() << "### not skipping undisplayed buffer";
+            return;
+        }
+
         surfaceBuffer = bufferQueue.takeFirst();
 
         int width = 0;
@@ -441,7 +446,7 @@ void Surface::damage(const QRect &rect)
 {
     Q_D(Surface);
 
-    if (!d->bufferQueue.isEmpty() && (!d->surfaceBuffer || d->surfaceBuffer->isFinished()) || !d->surfaceBuffer->handle() ) {
+    if (!d->bufferQueue.isEmpty() && (!d->surfaceBuffer || d->surfaceBuffer->isFinished() || !d->surfaceBuffer->handle())) {
             // Handle the "slow" case where we've finished the previous frame before the next damage comes.
             d->newCurrentBuffer();
             d->doUpdate(rect);