minor fix to SetParent()

reactos/subsys/win32k/ntuser

diff -u -r1.196 -r1.197
--- window.c	27 Feb 2004 01:05:45 -0000	1.196
+++ window.c	27 Feb 2004 22:21:32 -0000	1.197
@@ -16,7 +16,7 @@

  *  along with this program; if not, write to the Free Software
  *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  */

-/* $Id: window.c,v 1.196 2004/02/27 01:05:45 weiden Exp $

+/* $Id: window.c,v 1.197 2004/02/27 22:21:32 weiden Exp $

  *
  * COPYRIGHT:        See COPYING in the top level directory
  * PROJECT:          ReactOS kernel

@@ -872,7 +872,10 @@

    HWND hWnd, hWndNewParent, hWndOldParent;
    BOOL WasVisible;
    BOOL MenuChanged;

-

+   
+   ASSERT(Wnd);
+   ASSERT(WndNewParent);
+   

    hWnd = Wnd->Self;
    hWndNewParent = WndNewParent->Self;
 

@@ -908,8 +911,6 @@

       }
    }
    

-   if(WndOldParent)
-     IntReleaseWindowObject(WndOldParent);

    /*
     * SetParent additionally needs to make hwnd the topmost window
     * in the x-order and send the expected WM_WINDOWPOSCHANGING and

@@ -927,7 +928,19 @@

     * Validate that the old parent still exist, since it migth have been
     * destroyed during the last callbacks to user-mode 
     */

-   return !IntIsWindow(hWndOldParent) ? NULL : WndOldParent;

+   if(WndOldParent)
+   {
+     if(!IntIsWindow(WndOldParent->Self))
+     {
+       IntReleaseWindowObject(WndOldParent);
+       return NULL;
+     }
+     
+     /* don't dereference the window object here, it must be done by the caller
+        of IntSetParent() */
+     return WndOldParent;
+   }
+   return NULL;

 }
 
 BOOL FASTCALL

@@ -2311,6 +2324,7 @@

 
    if (!(Wnd = IntGetWindowObject(hWndChild)))
    {

+      IntReleaseWindowObject(WndParent);

       SetLastWin32Error(ERROR_INVALID_WINDOW_HANDLE);
       return NULL;
    }

@@ -2320,6 +2334,7 @@

    if (WndOldParent)
    {
       hWndOldParent = WndOldParent->Self;

+      IntReleaseWindowObject(WndOldParent);

    }
 
    IntReleaseWindowObject(Wnd);