Re: No DRI/DDX/DRM versions checks with old interface?

[Ian R. <id...@us...>]

Felix K=FChling wrote:
> On Fri, 30 Jul 2004 15:24:03 -0700
> Ian Romanick <id...@us...> wrote:
>=20
>>An old libGL will call the driver's CreateScreen function.  This=20
>>function calls __driUtilCreateScreen, which does the extra work that is=
=20
>>now done in a new libGL, then calls the driver's CreateNewScreen.=20
>>Whether you're using an old libGL or a new one, you eventually get to=20
>>CreateNewScreen.
>=20
> Not quite. __driUtilCreateScreen does call __driUtilCreateNewScreen, bu=
t
> from there you never get back to the driver's CreateNewScreen function.
> New interface drivers call __driUtilCreateNewScreen from
> driverCreateNewScreen, not the other way around. And the savage driver,
> which is not ported yet, doesn't even have a driverCreateNewScreen
> function. So I still believe a new driver loaded by an old libGL never
> checks the DRI/DDX/DRM versions.

Hmm...I looked at the code in __driUtilCreateScreen in dri_util.c.  I'm=20
inclined to say that the call to __driUtilCreateNewScreen should be a=20
call to __driCreateNewScreen instead.  I don't want to have any more=20
code than absolutely necessary in the "old" API compatibility path.  I=20
fully expect that code to get less and less testing as time goes on.=20
I'd rather not have bugs creep in.

In any case, could you file a bug on this in X.org bugzilla?  This code=20
is currently in the X.org tree, and there's a release coming up soon. ;)

> I verified this with the radeon driver by inserting a debug printf at
> the start of __driCreateNewScreen. Then I ran glxgears once with a new
> libGL and once with an old one (from XFree86 4.3). In the first case I
> saw the debug output, in the second case I didn't.
>=20
> I guess the version check in the InitDriver/CreateScreen function is
> still needed for the old interface.