dix: add dixResouceIsServerOwned()

Little helper function for checking whether a resource XID
belongs to the server itself.

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

Xext/security.c

@@ -762,7 +762,7 @@ SecurityResource(CallbackListPtr *pcbl, void *unused, void *calldata)
         goto denied;
 
     /* special checks for server-owned resources */
-    if (owner == serverClient) {
+    if (dixResouceIsServerOwned(rec->id)) {
         if (rec->rtype & RC_DRAWABLE)
             /* additional operations allowed on root windows */
             allowed |= SecurityRootWindowExtraMask;

dix/colormap.c

@@ -220,8 +220,6 @@ static void FindColorInRootCmap(ColormapPtr /* pmap */ ,
 	    (bits) += (base);		 	\
 	    while((bits) & ~(mask))		\
 		(bits) += ((bits) & ~(mask));
-/* ID of server as client */
-#define SERVER_ID	0
 
 typedef struct _colorResource {
     Colormap mid;
@@ -418,7 +416,7 @@ FreeColormap(void *value, XID mid)
     EntryPtr pent;
     ColormapPtr pmap = (ColormapPtr) value;
 
-    if (dixClientIdForXID(mid) != SERVER_ID) {
+    if (!dixResouceIsServerOwned(mid)) {
         (*pmap->pScreen->UninstallColormap) (pmap);
         WalkTree(pmap->pScreen, (VisitWindowProcPtr) TellNoMap, (void *) &mid);
     }

dix/resource_priv.h

@@ -82,4 +82,14 @@ static inline ClientPtr dixClientForXID(XID xid) {
     return NullClient;
 }
 
+/*
+ * @brief check whether resource is owned by server
+ *
+ * @param XID the ID of the resource to check
+ * @return TRUE if resource is server owned
+ */
+static inline Bool dixResouceIsServerOwned(XID xid) {
+    return (dixClientForXID(xid) == serverClient);
+}
+
 #endif /* _XSERVER_DIX_RESOURCE_PRIV_H */

hw/xwayland/xwayland-pixmap.h

@@ -50,7 +50,7 @@ Bool xwl_pixmap_init(void);
 static inline Bool
 xwl_is_client_pixmap(PixmapPtr pixmap)
 {
-    return dixClientForXID(pixmap->drawable.id) != serverClient;
+    return (!dixResouceIsServerOwned(pixmap->drawable.id));
 }
 
 #endif /* XWAYLAND_PIXMAP_H */