Cygwin/X: DirectDraw engines shouldn't try to blit if the surface wasn't allocated

Fix winShadowUpdateDD(|NL) so we don't try to blit to primary surface if it didn't get allocated

(Intel drivers, in particular, seem to like to issue a WM_DISPLAYCHANGE during a suspend/resume
cycle, but not allow surface to be allocated right then)

Also:
Use winReleasePrimarySurfaceShadowDD(|NL) in winFreeFBShadowDD(|NL) rather than open coding it
Don't mess about recreating surface if we're going to resize it anyhow

Signed-off-by: Jon TURNEY <jon.turney@dronecode.org.uk>
Reviewed-by: Colin Harrison <colin.harrison@virgin.net>
Tested-by: Colin Harrison <colin.harrison@virgin.net>

hw/xwin/winshaddd.c

@@ -514,25 +514,16 @@ winFreeFBShadowDD (ScreenPtr pScreen)
       pScreenPriv->pddsShadow = NULL;
     }
 
-  /* Detach the clipper from the primary surface and release the clipper. */
+  /* Detach the clipper from the primary surface and release the primary surface, if there is one */
-  if (pScreenPriv->pddcPrimary)
+  winReleasePrimarySurfaceShadowDD(pScreen);
-    {
-      /* Detach the clipper */
-      IDirectDrawSurface2_SetClipper (pScreenPriv->pddsPrimary,
-				      NULL);
 
   /* Release the clipper object */
+  if (pScreenPriv->pddcPrimary)
+    {
       IDirectDrawClipper_Release (pScreenPriv->pddcPrimary);
       pScreenPriv->pddcPrimary = NULL;
     }
 
-  /* Release the primary surface, if there is one */
-  if (pScreenPriv->pddsPrimary)
-    {
-      IDirectDrawSurface2_Release (pScreenPriv->pddsPrimary);
-      pScreenPriv->pddsPrimary = NULL;
-    }
-
   /* Free the DirectDraw2 object, if there is one */
   if (pScreenPriv->pdd2)
     {
@@ -577,6 +568,10 @@ winShadowUpdateDD (ScreenPtr pScreen,
   if ((!pScreenPriv->fActive && pScreenInfo->fFullScreen)
       || pScreenPriv->fBadDepth) return;
 
+  /* Return immediately if we didn't get needed surfaces */
+  if (!pScreenPriv->pddsPrimary || !pScreenPriv->pddsShadow)
+    return;
+
   /* Get the origin of the window in the screen coords */
   ptOrigin.x = pScreenInfo->dwXOffset;
   ptOrigin.y = pScreenInfo->dwYOffset;

hw/xwin/winshadddnl.c

@@ -546,25 +546,16 @@ winFreeFBShadowDDNL(ScreenPtr pScreen)
       pScreenPriv->pddsShadow4 = NULL;
     }
 
-  /* Detach the clipper from the primary surface and release the clipper. */
+  /* Detach the clipper from the primary surface and release the primary surface, if there is one */
-  if (pScreenPriv->pddcPrimary)
+  winReleasePrimarySurfaceShadowDDNL(pScreen);
-    {
-      /* Detach the clipper */
-      IDirectDrawSurface4_SetClipper (pScreenPriv->pddsPrimary4,
-				      NULL);
 
   /* Release the clipper object */
+  if (pScreenPriv->pddcPrimary)
+    {
       IDirectDrawClipper_Release (pScreenPriv->pddcPrimary);
       pScreenPriv->pddcPrimary = NULL;
     }
 
-  /* Release the primary surface, if there is one */
-  if (pScreenPriv->pddsPrimary4)
-    {
-      IDirectDrawSurface4_Release (pScreenPriv->pddsPrimary4);
-      pScreenPriv->pddsPrimary4 = NULL;
-    }
-
   /* Free the DirectDraw4 object, if there is one */
   if (pScreenPriv->pdd4)
     {
@@ -658,6 +649,10 @@ winShadowUpdateDDNL (ScreenPtr pScreen,
   if ((!pScreenPriv->fActive && pScreenInfo->fFullScreen)
       || pScreenPriv->fBadDepth) return;
 
+  /* Return immediately if we didn't get needed surfaces */
+  if (!pScreenPriv->pddsPrimary4 || !pScreenPriv->pddsShadow4)
+    return;
+
   /* Get the origin of the window in the screen coords */
   ptOrigin.x = pScreenInfo->dwXOffset;
   ptOrigin.y = pScreenInfo->dwYOffset;

hw/xwin/winwndproc.c

@@ -230,19 +230,8 @@ winWindowProc (HWND hwnd, UINT message,
         then we should do so here.  For the moment, assume it does.
         (this is probably usually the case so that might be an
         overoptimization)
-      */
-
-      /*
-       * We can simply recreate the same-sized primary surface when
-       * the display dimensions change.
       */
 	{
-
-#if CYGDEBUG
-	  winDebug ("winWindowProc - WM_DISPLAYCHANGE - Recreated "
-		  "primary surface\n");
-#endif
-
 	  /*
              In rootless modes which are monitor or virtual desktop size
              use RandR to resize the X screen
@@ -311,13 +300,8 @@ winWindowProc (HWND hwnd, UINT message,
           else
             {
               /*
-                If we get here, we are either windowed and using the GDI engine
+               * We can simply recreate the same-sized primary surface when
-                or windowed and non-fullscreen using any engine
+               * the display dimensions change.
-              */
-
-              /*
-               * For ddraw engines, we need to (try to) recreate the same-sized primary surface
-               * when display dimensions change (but not depth, that is disruptive)
                */
 
               /*