[PATCHES] remove direct access to fb module from exa

Maarten Maathuis madman2003 at gmail.com
Mon Feb 2 09:50:18 PST 2009

On Mon, Feb 2, 2009 at 5:27 PM, Michel Dänzer <michel at daenzer.net> wrote:
> On Mon, 2009-02-02 at 16:08 +0100, Maarten Maathuis wrote:
>> The problem about mangling with fb symbols is that you need to do it
>> at runtime, that would turn out to be very awkward, not to mention
>> incorrect. For fallbacks we need to obey the wrap chain at all times.
>> I will check if core font rendering is somehow slow, but i wouldn't
>> know any correct fix.
>> The case of patch 8 is something i cannot avoid, since fallbacks have
>> to go through a wrapped function, that means i need a boolean return
>> value, instead of void. Making brand new code seemed more error prone.
> What I mean is to build e.g. fbcopy.c into libexa.so, mangling the
> symbol names to something like exaFbCopyRegion if necessary.

It would require modifying fbcopy.c, partially because i need return
values on some of the functions. I would also have to split the file
up, because half of that file is not "machine independent". I could
perhaps strip out a part of fbcopy.c and move it to mi. As long as it
doesn't require fixing code i don't know.

>> And yes, with this you can load and run wfb without crashing, my first
>> attempts haven't resulted in correct rendering, but i'm probably
>> misunderstanding the memory layout for my particular hardware.
> Still, may want to wait until you can rule out a problem with these
> patches?

Normal X gives no regressions and just using wfb with linear accessors
(1:1 usage of memory address) is fine too. I see no reason to hold up
these patches for those reasons.

> --
> Earthling Michel Dänzer           |                http://www.vmware.com
> Libre software enthusiast         |          Debian, X and DRI developer

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