dix: clean up MakeWindowOptional() calls and add alloc fault checks

a) no need to checking for win->optional == NULL before calling
   MakeWindowOptional(), because it checks itself
   (except some cases where it's presence has it's own semantics,
   or prevent unnecessary allocations)
b) lots of call sites didn't check for allocation failure.

Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>

Xext/saver.c

@@ -495,13 +495,11 @@ CreateSaverWindow(ScreenPtr pScreen)
         mask |= CWBorderPixmap;
     }
     if (pAttr->pCursor) {
-        CursorPtr cursor;
+        if (!MakeWindowOptional(pWin)) {
-        if (!pWin->optional)
+            FreeResource(pWin->drawable.id, X11_RESTYPE_NONE);
-            if (!MakeWindowOptional(pWin)) {
+            return FALSE;
-                FreeResource(pWin->drawable.id, X11_RESTYPE_NONE);
+        }
-                return FALSE;
+        CursorPtr cursor = RefCursor(pAttr->pCursor);
-            }
-        cursor = RefCursor(pAttr->pCursor);
         if (pWin->optional->cursor)
             FreeCursor(pWin->optional->cursor, (Cursor) 0);
         pWin->optional->cursor = cursor;

Xext/shape.c

@@ -268,8 +268,9 @@ ShapeRectangles(ClientPtr client, xShapeRectanglesReq *stuff)
         return BadMatch;
     srcRgn = RegionFromRects(nrects, prects, ctype);
 
-    if (!pWin->optional)
+    if (!MakeWindowOptional(pWin))
-        MakeWindowOptional(pWin);
+        return BadAlloc;
+
     switch (stuff->destKind) {
     case ShapeBounding:
         destRgn = &pWin->optional->boundingShape;
@@ -364,8 +365,9 @@ ShapeMask(ClientPtr client, xShapeMaskReq *stuff)
             return BadAlloc;
     }
 
-    if (!pWin->optional)
+    if (!MakeWindowOptional(pWin))
-        MakeWindowOptional(pWin);
+        return BadAlloc;
+
     switch (stuff->destKind) {
     case ShapeBounding:
         destRgn = &pWin->optional->boundingShape;
@@ -441,8 +443,9 @@ ShapeCombine(ClientPtr client, xShapeCombineReq *stuff)
     rc = dixLookupWindow(&pDestWin, stuff->dest, client, DixSetAttrAccess);
     if (rc != Success)
         return rc;
-    if (!pDestWin->optional)
+    if (!MakeWindowOptional(pDestWin))
-        MakeWindowOptional(pDestWin);
+        return BadAlloc;
+
     switch (stuff->destKind) {
     case ShapeBounding:
         createDefault = CreateBoundingShape;
@@ -490,8 +493,9 @@ ShapeCombine(ClientPtr client, xShapeCombineReq *stuff)
     else
         srcRgn = (*createSrc) (pSrcWin);
 
-    if (!pDestWin->optional)
+    if (!MakeWindowOptional(pDestWin))
-        MakeWindowOptional(pDestWin);
+        return BadAlloc;
+
     switch (stuff->destKind) {
     case ShapeBounding:
         destRgn = &pDestWin->optional->boundingShape;

Xi/exevents.c

@@ -2740,7 +2740,7 @@ AddExtensionClient(WindowPtr pWin, ClientPtr client, Mask mask, int mskidx)
 {
     InputClientsPtr others;
 
-    if (!pWin->optional && !MakeWindowOptional(pWin))
+    if (!MakeWindowOptional(pWin))
         return BadAlloc;
     others = AllocInputClient();
     if (!others)

dix/events.c

@@ -4587,7 +4587,7 @@ XRetCode EventSelectForWindow(WindowPtr pWin, ClientPtr client, Mask mask)
             }
         }
         check = 0;
-        if (!pWin->optional && !MakeWindowOptional(pWin))
+        if (!MakeWindowOptional(pWin))
             return BadAlloc;
         others = calloc(1, sizeof(OtherClients));
         if (!others)
@@ -4646,7 +4646,7 @@ EventSuppressForWindow(WindowPtr pWin, ClientPtr client,
         }
     }
     else {
-        if (!pWin->optional && !MakeWindowOptional(pWin)) {
+        if (!MakeWindowOptional(pWin)) {
             if (pWin->dontPropagate)
                 DontPropagateRefCnts[pWin->dontPropagate]++;
             return BadAlloc;

dix/grabs.c

@@ -564,7 +564,7 @@ AddPassiveGrabToList(ClientPtr client, GrabPtr pGrab)
         }
     }
 
-    if (!pGrab->window->optional && !MakeWindowOptional(pGrab->window)) {
+    if (!MakeWindowOptional(pGrab->window)) {
         FreeGrab(pGrab);
         return BadAlloc;
     }
@@ -663,8 +663,7 @@ DeletePassiveGrabFromList(GrabPtr pMinuendGrab)
                        DeleteDetailFromMask(grab->modifiersDetail.pMask,
                                             pMinuendGrab->modifiersDetail.
                                             exact))
-                     || (!pNewGrab->window->optional &&
+                     || (!MakeWindowOptional(pNewGrab->window))) {
-                         !MakeWindowOptional(pNewGrab->window))) {
                 FreeGrab(pNewGrab);
                 ok = FALSE;
             }

dix/property.c

@@ -316,7 +316,7 @@ dixChangeWindowProperty(ClientPtr pClient, WindowPtr pWin, Atom property,
     rc = dixLookupProperty(&pProp, pWin, property, pClient, access_mode);
 
     if (rc == BadMatch) {       /* just add to list */
-        if (!pWin->optional && !MakeWindowOptional(pWin))
+        if (!MakeWindowOptional(pWin))
             return BadAlloc;
         pProp = dixAllocateObjectWithPrivates(PropertyRec, PRIVATE_PROPERTY);
         if (!pProp)

dix/window.c

@@ -1317,7 +1317,7 @@ ChangeWindowAttributes(WindowPtr pWin, Mask vmask, XID *vlist, ClientPtr client)
             break;
         case CWBackingPlanes:
             if (pWin->optional || ((CARD32) *pVlist != (CARD32) ~0L)) {
-                if (!pWin->optional && !MakeWindowOptional(pWin)) {
+                if (!MakeWindowOptional(pWin)) {
                     error = BadAlloc;
                     goto PatchUp;
                 }
@@ -1329,7 +1329,7 @@ ChangeWindowAttributes(WindowPtr pWin, Mask vmask, XID *vlist, ClientPtr client)
             break;
         case CWBackingPixel:
             if (pWin->optional || (CARD32) *pVlist) {
-                if (!pWin->optional && !MakeWindowOptional(pWin)) {
+                if (!MakeWindowOptional(pWin)) {
                     error = BadAlloc;
                     goto PatchUp;
                 }
@@ -1430,7 +1430,7 @@ ChangeWindowAttributes(WindowPtr pWin, Mask vmask, XID *vlist, ClientPtr client)
 
                 for (pChild = pWin->firstChild; pChild;
                      pChild = pChild->nextSib) {
-                    if (!pChild->optional && !MakeWindowOptional(pChild)) {
+                    if (!MakeWindowOptional(pChild)) {
                         error = BadAlloc;
                         goto PatchUp;
                     }
@@ -3430,7 +3430,7 @@ ChangeWindowDeviceCursor(WindowPtr pWin, DeviceIntPtr pDev, CursorPtr pCursor)
     ScreenPtr pScreen;
     WindowPtr pChild;
 
-    if (!pWin->optional && !MakeWindowOptional(pWin))
+    if (!MakeWindowOptional(pWin))
         return BadAlloc;
 
     /* 1) Check if window has device cursor set

xfixes/region.c

@@ -658,8 +658,8 @@ SingleXFixesSetWindowShapeRegion(ClientPtr client, xXFixesSetWindowShapeRegionRe
         pRegion = XFixesRegionCopy(pRegion);
         if (!pRegion)
             return BadAlloc;
-        if (!pWin->optional)
+        if (!MakeWindowOptional(pWin))
-            MakeWindowOptional(pWin);
+            return BadAlloc;
         switch (stuff->destKind) {
         default:
         case ShapeBounding: