Re: [OE-Core][RFC PATCH 06/13] systemd: Add PACKAGECONFIG for sysvinit

["Adrian Bunk" <bunk@stusta.de>]

On Thu, Mar 26, 2020 at 06:08:52PM +0000, Alex Kiernan wrote:
> On Thu, Mar 26, 2020 at 5:33 PM Adrian Bunk <bunk@stusta.de> wrote:
> >
> > On Thu, Mar 26, 2020 at 03:54:55PM +0000, Alex Kiernan wrote:
> > > On Thu, Mar 26, 2020 at 2:56 PM Adrian Bunk <bunk@stusta.de> wrote:
> > > > On Thu, Mar 26, 2020 at 08:54:19AM +0000, Alex Kiernan wrote:
> > > > > Add sysvinit PACKAGECONFIG which is bound to DISTRO_FEATURES, this
> > > > > then disables all sysvinit handling in systemd if it isn't present.
> > > > >
> > > > > Consolidate sysvinit handling so that when it's disabled we exclude all
> > > > > sysvinit features.
> > > > >...
> > > >
> > > > What exactly are "sysvinit handling" and "sysvinit features"?
> > > >
> > > > It seems to disable systemd-sysv-generator, and this is wrong.
> > >
> > > Like this it sets HAVE_SYSV_COMPAT which does disable
> > > systemd-sysv-generator, but if sysvinit is disabled completely in the
> > > distro, I'm missing why that's a bad thing?
> > >
> > > Or have I misunderstood what sysvinit in DISTRO_FEATURES is meant to
> > > mean?
> >
> > sysvinit in DISTRO_FEATURES means that sysvinit is supported as init system.
> >
> > > I'd taken in that sysvinit not present in DISTRO_FEATURES meant
> > > that packages should install systemd units, not rely on init scripts.
> >
> > Packages that do provide both are not the relevant ones.
> >
> > For packages that can provide both, if the init script gets installed
> > it is ignored by systemd when there is also a systemd unit.
> >
> > systemd-sysv-generator provides support for packages that do not
> > (yet) provide a systemd unit, only an init script.
> >
> > Disabling this could save a few bytes on a small system when no
> > installed package needs it, but this is not in any way related
> > to sysvinit in DISTRO_FEATURES.
> 
> That's the piece of context I'm missing then... so whilst adding
> sysvinit as a PACKAGECONFIG is valid, it shouldn't be linked to
> DISTRO_FEATURES?

Yes, and it should stay enabled by default.

cu
Adrian