[PATCH] Return BadWindow instead of BadMatch from dixLookupWindow

[Julien Cristau]

On Sat, Jun  5, 2010 at 16:41:42 +0200, Julien Cristau wrote:

> From: Ben Hutchings <ben at decadent.org.uk>
> 
> BadMatch is not a documented error code for XGetWindowProperty which
> sends X_GetProperty requests.  However, the implementation in Xorg
> appears to return BadMatch if and only if it's passed a reference to a
> drawable that isn't a window.
> 
> I don't understand how the server coordinates window changes with the
> WM.  Is it possible that a window can be completely deleted before the
> WM has handled it?  In that case there is presumably a race condition
> where a window could disppear and another drawable be created with the
> same id.
> 
> I would suggest the following change.  This is untested because the
> BadWindow or BadMatch error is dependent on a race condition if I
> understand correctly.  But it's "obviously correct". :-)
> 
> Debian bug#491979 <http://bugs.debian.org/491979>
> ---
> Ben sent this patch to the Debian bug in 2008, but this seems to still
> apply to the current code.  The initial report was a ion3 crash because
> it got unexpected BadMatch errors from XGetWindowProperty.
> 
Disregard this, the bug was already fixed in commit f04fe06ae24.  Sorry
for the noise.

http://cgit.freedesktop.org/xorg/xserver/commit?id=f04fe06ae244b851b38be824b1a80f2f8a030591

Cheers,
Julien