[PATCH]: mtdev could be disabled at configuration

[Pekka Paalanen]

On Mon, 10 Jun 2013 09:47:32 +0200
Marc Chalain <marc.chalain at gmail.com> wrote:

> Hi Pekka,
> I agree with --disable-multitouch.
> For the comparison between the use of ifdef and no-op functions. I think
> the second solution is ambiguous, we disable the feature in one side and we
> use the API in the other side.
> I look if it's possible to have a third solution which satisfies every
> body...

In this case, the no-op functions would never be called, anyway.

#ifdefs are harder to read than function calls, when functions are well
named, and live up to their names. The linux kernel favours this, too.


Cheers,
pq

> 2013/6/10 Pekka Paalanen <ppaalanen at gmail.com>
> 
> > On Fri, 7 Jun 2013 12:11:14 +0200
> > Marc Chalain <marc.chalain at gmail.com> wrote:
> >
> > > mtdev is not necessary on some device (desktop or set-top-box). For
> > > embedded solution the minimum of dependencies is required. "configure"
> > > accepts the --disable-mtdev option.
> >
> > Hi Marc,
> >
> > with this patch, if weston is compiled with --disable-mtdev, it looks
> > like it will still happily open multitouch devices, expose them to
> > Wayland clients, and feed them garbage or fail or whatever. Right?
> >
> > I think the proper approach is to change the configure option into
> > --disable-multitouch or --disable-touchscreen, which would not only
> > drop the dependency to mtdev, but also make Weston ignore all
> > touchscreen devices since it will not be able to handle them.
> >
> > As the cherry on top, when a touchscreen device gets ignored during
> > input device detection, it would be nice to print a log message saying
> > it was ignored because touchscreen support was not built, instead of
> > the usual log message.
> >
> > Also, there are not that many mtdev functions, so to minimize the
> > number of #ifdefs is the code, you could define no-op functions for a
> > few mtdev entry points when the real mtdev is not used.
> >
> >
> > Thanks,
> > pq
> >