Re: GDM status (again)

[Andy Wingo]

Hi!

On Sun 29 Oct 2017 16:30, address@hidden (Ludovic Courtès) writes:

> Timothy Sample <address@hidden> skribis:
>
>> Two months ago, Andy Wingo did a bunch of work on getting GDM working as
>> a display manager for Guix [1]. Unfortunately, Andy had to step away
>> from the task before getting everything working.
>
> Thanks for taking it over!

OMG yes, thank you!!  Excellent work!

>> After clearing that up, I found out that GDM was unable to find the
>> Gnome Shell. This is pretty tricky because Gnome Shell already depends
>> on GDM, so you have to avoid a circular dependency. Other distros (I
>> looked at Debian and Fedora) solve this by slicing out a “libgdm” output
>> from the GDM sources, so that you can build “libgdm” without Gnome
>> Shell, have Gnome Shell depend on “libgdm”, and then have GDM depend on
>> Gnome Shell.
>
> Do we really need a compile-time dependency (GDM in master doesn’t
> depend on gnome-shell, after all), or can we just have a hard-coded
> /run/current-system/bin/gnome-shell somewhere?  Granted, that’s not very
> elegant, but it might be good enough?
>
> Also, one can use GDM without using GNOME, so it would be best if GDM
> didn’t depend on GNOME.

This might be fine (and is what I was trying to do).  However this would
mean that the GDM service should ensure that gnome-shell is there, which
in practice is like having a dependency on GNOME or at least on
gnome-shell.  My understanding is that GDM uses gnome-shell as the login
greeter process, so you really can't use GDM without GNOME -- of course
you can log in to some non-GNOME session but GDM itself will use
gnome-shell.  Given that's the case, might as well depend on gnome-shell
explicitly.

> With this and the other changes you described, it looks like there’s
> already a bunch of patches we could apply.  Would you like to send them?
> :-)

I'd be happy to review.  I'd also be happy to apply them :)  There's no
currently-working thing to break -- we can only get better -- so I think
it's OK to noodle on the problem in master.

> Thanks for the detailed report, and thanks in advance for the patches
> you described!  :-)

Yes, looking forward to the patches :-))

Andy