d3dvideosink: Fix crash on WinProc handler

... caused by null pointer dereference. The d3dvideosink object might
not available yet on the handler.

diff --git a/sys/d3dvideosink/d3dhelpers.c b/sys/d3dvideosink/d3dhelpers.c
index a145f53..f6a7b8d 100644 (file)
--- a/sys/d3dvideosink/d3dhelpers.c
+++ b/sys/d3dvideosink/d3dhelpers.c
@@ -2046,6 +2046,11 @@ d3d_wnd_proc (HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
   WNDPROC proc;
   LRESULT ret = 0;
 
+  /* d3dvideosink object might not available yet.
+   * The thread for message queue starts earlier than SetProp... */
+  if (!sink)
+    return DefWindowProc (hWnd, message, wParam, lParam);
+
   LOCK_SINK (sink);
   proc = sink->d3d.orig_wnd_proc;
   UNLOCK_SINK (sink);