Solved a crash in multiwindow mode due to a crash overflow:

- Make sure WM_WM_REINIT and WM_WM_MOVE do not have the same value
- Make sure the nextview handle is not the same as the window itself

1 files changed, 25 insertions, 2 deletions

diff --git a/xorg-server/hw/xwin/winclipboardwndproc.c b/xorg-server/hw/xwin/winclipboardwndproc.c
index dbfc61e4e..26a77ef74 100644
--- a/xorg-server/hw/xwin/winclipboardwndproc.c
+++ b/xorg-server/hw/xwin/winclipboardwndproc.c
@@ -38,6 +38,9 @@
 #include "winclipboard.h"

 #include "misc.h"

 #include "winmsg.h"

+#include "objbase.h"

+#include "ddraw.h"

+#include "winwindow.h"

 

 /*

  * Constants

@@ -183,6 +186,14 @@ winClipboardWindowProc (HWND hwnd, UINT message,
 	

 	/* Add ourselves to the clipboard viewer chain */

 	s_hwndNextViewer = SetClipboardViewer (hwnd);

+	#ifdef _DEBUG

+	if (s_hwndNextViewer== hwnd)

+	{

+	  ErrorF("WM_CREATE: SetClipboardViewer returned own window. This causes an endless loop, so reset s_hwndNextViewer. ");

+	  s_hwndNextViewer=NULL;

+	}

+	#endif

+

       }

       return 0;

 

@@ -196,6 +207,11 @@ winClipboardWindowProc (HWND hwnd, UINT message,
 	if ((HWND) wParam == s_hwndNextViewer)

 	  {

 	    s_hwndNextViewer = (HWND) lParam;

+	    if (s_hwndNextViewer == hwnd)

+	    {

+	      winDebug("WM_CHANGECBCHAIN: trying to set s_hwndNextViewer to own window. Resetting it back to NULL. ");

+	      s_hwndNextViewer=NULL;  /* This would cause an endless loop, so break it by ending the loop here. I have seen this happening, why??? */

+	    }

 	  }

 	else if (s_hwndNextViewer)

 	  SendMessage (s_hwndNextViewer, message,

@@ -231,9 +247,16 @@ winClipboardWindowProc (HWND hwnd, UINT message,
         { 

           winDebug ("  WM_WM_REINIT: Replacing us(%x) with %x at head "

 		    "of chain\n", hwnd, s_hwndNextViewer);

-	  ChangeClipboardChain (hwnd, s_hwndNextViewer);

+	  if (!wParam) ChangeClipboardChain (hwnd, s_hwndNextViewer);   /* When wParam is set, the window was already removed from the chain */

 	  winDebug ("  WM_WM_REINIT: Putting us back at head of chain.\n");

 	  s_hwndNextViewer = SetClipboardViewer (hwnd);

+	  #ifdef _DEBUG

+	  if (s_hwndNextViewer== hwnd)

+	  {

+	    ErrorF("WM_WM_REINIT: SetClipboardViewer returned own window. This causes an endless loop, so reset s_hwndNextViewer. ");

+	    s_hwndNextViewer=NULL;

+	  }

+	  #endif

         }

         winDebug ("winClipboardWindowProc - WM_WM_REINIT: Exit\n");

       }

@@ -277,7 +300,7 @@ winClipboardWindowProc (HWND hwnd, UINT message,
 	  {

 	    /* Attempt to break the nesting by getting out of the chain, twice?, and then fix and bail */

 	    ChangeClipboardChain (hwnd, s_hwndNextViewer);

-	    winFixClipboardChain();

+	    winFixClipboardChain(1);

 	    ErrorF ("winClipboardWindowProc - WM_DRAWCLIPBOARD - "

 			   "Nested calls detected.  Re-initing.\n");

 	    winDebug ("winClipboardWindowProc - WM_DRAWCLIPBOARD: Exit\n");