[Wine] Re: Page Fault With Freetype calls

[Zach Lawson]

Great!

I'll get to work on testing out this patch, and let you know what I  
come up with.

Thanks again for the help!

-Zach
On Nov 16, 2005, at 1:15 PM, Rein Klazes wrote:

> On Wed, 16 Nov 2005 09:05:45 -0500, in gmane.comp.emulators.wine.user
> you wrote:
>
>> The aforementioned 200 lines before the exception:
>
> Thanks, that is enough. Here is an explanation and a patch cc 'd to  
> the
> patches list for inclusion in Wine. It would be nice if you could test
> the patch (you need to compile wine from source for that).
>
> The programs does:
> - call GetFontData with buffer size zero, to return the required  
> buffer
> size;
> - do that for a number of font tables, adding the required sizes;;
> - allocate a buffer large enough to store the data from all the
> GetFontData calls;
> - then filling the buffer with GetFontData calls, using the return  
> value
> of the call to calculate the remaining free size.
>
> size=0
> size = size + GetFontData(..., NULL, 0);
> ...
> size = size + GetFontData(..., NULL, 0);
> buf = VirtualAlloc( ..., size, ...);
> ret = GetFontData(..., buf, size);
> size = size - ret;
> buf = size + ret;
> ret = GetFontData(..., buf, size);
>
> Here it goes wrong because Wine's GetFontData is not returning the
> actual size of the data put in the buffer, but the buffer size it  
> self.
> The pointer to the buffer data is now pointing beyond the boundary. It
> does not go wrong immediately because size is zero now, but at the
> following GetFontData call the page fault is inevitable.
>
> Changelog:
> dlls/gdi	: font.c
> Make GetFontData return the actual number of bytes put in the buffer.
>
> Rein.
> <getfontdata.diff>