[PATCH 15/19] xfree86: don't export xf86InputDevs.

[Peter Hutterer]

On Wed, Sep 08, 2010 at 01:54:41AM -0300, Fernando Carrijo wrote:
> Peter Hutterer <peter.hutterer at who-t.net> wrote:
> 
> > On Tue, Sep 07, 2010 at 11:37:33PM -0300, Fernando Carrijo wrote:
> > > Peter Hutterer <peter.hutterer at who-t.net> wrote:
> > > 
> > > > Use xf86FirstLocalDevice() instead (but don't get me started on the naming
> > > > of that one...)
> > > 
> > > Yeah, a poorly chosen name indeed.
> > > 
> > > > Signed-off-by: Peter Hutterer <peter.hutterer at who-t.net>
> > > 
> > > Reviewed-by: Fernando Carrijo <fcarrijo at freedesktop.org>
> > > 
> > > > ---
> > > >  hw/xfree86/common/xf86Xinput.h |    2 +-
> > > >  1 files changed, 1 insertions(+), 1 deletions(-)
> > > > 
> > > > diff --git a/hw/xfree86/common/xf86Xinput.h b/hw/xfree86/common/xf86Xinput.h
> > > > index 45bf573..7d0c44e 100644
> > > > --- a/hw/xfree86/common/xf86Xinput.h
> > > > +++ b/hw/xfree86/common/xf86Xinput.h
> > > > @@ -122,7 +122,7 @@ struct _InputInfoRec {
> > > >  typedef InputInfoRec *InputInfoPtr;
> > > >  
> > > >  /* xf86Globals.c */
> > > > -extern _X_EXPORT InputInfoPtr xf86InputDevs;
> > > > +extern InputInfoPtr xf86InputDevs;
> > > 
> > > Out of personal interest: I still don't understand how closed-source drivers
> > > should deal with modifications like this. Initially I thought that exporting
> > > a symbol represented a contract the server could never decline, but it seems
> > > things do not work this way.
> > >
> > > The above change can be considered an API break? And are drivers supposed to
> > > check for the server version before they assume xf86InputDevs can be directly
> > > accessed?
> > 
> > The server has two APIs. One is the X protocol and its extension and these
> > are indeed set in stone. toolkits, clients, etc. rely on it and we don't
> > break it (or try not to in most cases anyway).
> > 
> > the other API is the video and input driver API. we have ABI_XINPUT_MAJOR
> > and it is bumped each time we introduce incompatible changes for input
> > drivers.. throughout a server release it stays the same so that drivers will
> > work with any e.g.  1.8.x version. between major releases of the server, all
> > bets are off. This commit is part of a series and one of the first in this
> > series bumps the ABI to 12, so drivers can indeed adjust to these new calls.
> 
> I got the picture.
> 
> The header xf86Module.h defines macros like ABI_XINPUT_VERSION, which are
> processed at build time by configure.ac:extract_abi(), and made available
> to xorg-server.pc via AC_SUBST([abi_xinput]).
> 
> Wish I knew the autotools since the day I first read the X server code.

mind you, atm none of our input drivers uses pkg-config to get the ABI
version since we're trying to support multiple servers. it's really just
ifdefs all over the place.

Cheers,
  Peter