[cairo] [PATCH] Avoid potential crash when subsurface's size is less than 0.

[Chris Wilson]

On Tue, 13 Mar 2012 10:00:37 +0800, Chuanbo Weng <strgnm at gmail.com> wrote:
> When cairo_surface_create_for_rectangle() get non-integer parameters,
> the subsurface's size may be negative(e.g x = 0.2, width = 0.7, the
> final width will be -1). It may cause crash somewhere when use this
> subsurface. Although fractional surface is ill-defined, we should avoid
> crash when pass non-integer parameter.

I modified the patch slightly to reject an invalid negative width/height
passed in by the user as well as fixing up the case where we compute
the negative surface size.

Thanks,
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre