Re: comctl32: Don't crash when getting a bad image list handle. (try 2)

[Francois Gouget]

On Mon, 19 Sep 2011, Nikolay Sivov wrote:
[...]
> > static inline BOOL is_valid(HIMAGELIST himl)
> >   {
> > - return himl&&  himl->lpVtbl ==&ImageListImpl_Vtbl;
> > - BOOL valid;
> > - __TRY
> > - {
> > -
> >    valid = himl&&  himl->lpVtbl ==&ImageListImpl_Vtbl;
> > - }
> > - __EXCEPT_PAGE_FAULT
> > - {
> > -
> >    valid = FALSE;
> > - }
> > - __ENDTRY
> > - return valid;
> > }
>
> Maybe use IsBadReadPtr() with sizeof(void*) is better? You need only vtable
> pointer to be accessible.

I prefer this construct as using IsBadReadPtr() would introduce a race 
in is_valid(). Of course calling is_valid() is in itself racy anyway. So 
I don't mind switching over if that's preferred (the code would have 
fewer lines).