[PATCH v5 3/7] launcher-logind: only get a VT on seat0, as only seat0 supports VTs

[Peter Hutterer]

On Fri, Jan 19, 2018 at 04:24:59PM +0200, Pekka Paalanen wrote:
> On Fri, 29 Dec 2017 13:31:49 -0500
> nerdopolis <bluescreen_avenger at verizon.net> wrote:
> 
> > As only seat0 supports TTYs, this changes the logind launcher where
> > it detects a TTY, only if the seat is seat0. This has only been
> > tested for logind
> > ---
> >  libweston/launcher-logind.c | 22 ++++++++++++----------
> >  libweston/launcher-util.c   |  4 ++++
> >  2 files changed, 16 insertions(+), 10 deletions(-)
> > 
> > diff --git a/libweston/launcher-logind.c b/libweston/launcher-logind.c
> > index 21d8c37b..875db70f 100644
> > --- a/libweston/launcher-logind.c
> > +++ b/libweston/launcher-logind.c
> > @@ -769,18 +769,20 @@ launcher_logind_connect(struct weston_launcher **out, struct weston_compositor *
> >  		free(t);
> >  		goto err_session;
> >  	}
> > -	free(t);
> >  
> > -	r = weston_sd_session_get_vt(wl->sid, &wl->vtnr);
> > -	if (r < 0) {
> > -		weston_log("logind: session not running on a VT\n");
> > -		goto err_session;
> > -	} else if (tty > 0 && wl->vtnr != (unsigned int )tty) {
> > -		weston_log("logind: requested VT --tty=%d differs from real session VT %u\n",
> > -			   tty, wl->vtnr);
> > -		r = -EINVAL;
> > -		goto err_session;
> > +	if (!strcmp(t, "seat0")) {
> > +		r = weston_sd_session_get_vt(wl->sid, &wl->vtnr);
> > +		if (r < 0) {
> > +			weston_log("logind: session not running on a VT\n");
> > +			goto err_session;
> > +		} else if (tty > 0 && wl->vtnr != (unsigned int )tty) {
> > +			weston_log("logind: requested VT --tty=%d differs from real session VT %u\n",
> > +				   tty, wl->vtnr);
> > +			r = -EINVAL;
> > +			goto err_session;
> > +		}
> >  	}
> > +	free(t);
> >  
> >  	loop = wl_display_get_event_loop(compositor->wl_display);
> >  	r = weston_dbus_open(loop, DBUS_BUS_SYSTEM, &wl->dbus, &wl->dbus_ctx);
> > diff --git a/libweston/launcher-util.c b/libweston/launcher-util.c
> > index 96a0ba6f..777ab755 100644
> > --- a/libweston/launcher-util.c
> > +++ b/libweston/launcher-util.c
> > @@ -111,6 +111,10 @@ WL_EXPORT void
> >  weston_setup_vt_switch_bindings(struct weston_compositor *compositor)
> >  {
> >  	uint32_t key;
> > +	struct weston_launcher *launcher = compositor->launcher;
> > +
> > +	if (launcher->iface->get_vt(launcher) == 0)
> > +		return;
> >  
> >  	if (compositor->vt_switching == false)
> >  		return;
> 
> Reviewed-by: Pekka Paalanen <pekka.paalanen at collabora.co.uk>
> 
> Although I'm not quite sure whether the VT-ful seat's name is
> configurable in logind or elsewhere, wondering whether "If your seat is
> not called seat0, you don't get VT switching." could surprise someone.

the string "seat0" is hardcoded all over systemd's sources, I'm assuming
it's not configurable without significant efforts :)
A quick skim also shows quite a few error messages to happen when the VT
seat is not seat0, so I think we're good.

The patch looks good, too, so
Reviewed-by: Peter Hutterer <peter.hutterer at who-t.net>

Cheers,
   Peter