Henri Verbeet : wined3d: Make sure we release the correct DC in context_update_window().

[Alexandre Julliard]

Module: wine
Branch: master
Commit: 82e39ced7f3c2c513c95b4e52c446d23d4e2946b
URL:    http://source.winehq.org/git/wine.git/?a=commit;h=82e39ced7f3c2c513c95b4e52c446d23d4e2946b

Author: Henri Verbeet <hverbeet at codeweavers.com>
Date:   Thu Apr 21 22:39:29 2011 +0200

wined3d: Make sure we release the correct DC in context_update_window().

---

 dlls/wined3d/context.c |   13 ++++++++++++-
 1 files changed, 12 insertions(+), 1 deletions(-)

diff --git a/dlls/wined3d/context.c b/dlls/wined3d/context.c
index 18c9438..3d07a35 100644
--- a/dlls/wined3d/context.c
+++ b/dlls/wined3d/context.c
@@ -873,7 +873,18 @@ static void context_update_window(struct wined3d_context *context)
 
     if (context->valid)
     {
-        if (!ReleaseDC(context->win_handle, context->hdc))
+        /* You'd figure ReleaseDC() would fail if the DC doesn't match the
+         * window. However, that's not what actually happens, and there are
+         * user32 tests that confirm ReleaseDC() with the wrong window is
+         * supposed to succeed. So explicitly check that the DC belongs to
+         * the window, since we want to avoid releasing a DC that belongs to
+         * some other window if the original window was already destroyed. */
+        if (WindowFromDC(context->hdc) != context->win_handle)
+        {
+            WARN("DC %p does not belong to window %p.\n",
+                    context->hdc, context->win_handle);
+        }
+        else if (!ReleaseDC(context->win_handle, context->hdc))
         {
             ERR("Failed to release device context %p, last error %#x.\n",
                     context->hdc, GetLastError());