[PATCH] spec: Do not disable some systemd units of newly split package

[Martin Kletzander]

Since virtproxyd was split into libvirt-daemon-proxy package it can
happen that, in case a distribution has such systemd preset, when
installing this package, already pre-enabled and configured units like
-tls.socket and -tcp.socket will get disabled.

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=2210058
Fixes: 5358618b1cd0afc126aed313249bf2134731665f
Signed-off-by: Martin Kletzander <mkletzan at redhat.com>
---
This is more like an RFC as I would really like to know what to really do in
this case.  What happens, basically, is that if you have libvirt-daemon-9.0.0
and set up virtproxyd-tls.socket for example and then upgrade to anything newer,
then the package libvirt-daemon-proxy will get installed.  The %post action
calls "%libvirt_daemon_systemd_post_inet virtproxyd" which calls "%systemd_post
with all virtproxyd units.  What %systemd_post is supposed to do is reset units
to a preset state in the case of package installation, but not during upgrade.
However the libvirt-daemon-proxy package did not exist on the system before, so
this action is not an update, but an installation.

If no preset is mentioned for a unit then `systemctl preset` does not change
anything.  However some distros might have a catch-all preset "disable *" for
some reason, I guess based on an example in the documentation, and there is no
way to override an already configured preset, you can only enable or disable a
unit in a preset.

That all means than it can happen that you enable virtproxyd-tcp.socket, for
example, then update your system and find that it is disabled.  There are
various ways to deal with this, but I don't see any one that would 100% satisfy
me with regards to all the issues and at the same time could be implemented
"soon enough" given libvirt already had three releases with the
libvirt-daemon-proxy split.

 libvirt.spec.in | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/libvirt.spec.in b/libvirt.spec.in
index 1f77cd90b772..50f521b7ce88 100644
--- a/libvirt.spec.in
+++ b/libvirt.spec.in
@@ -1592,7 +1592,13 @@ fi
 
 %post daemon-proxy
 %if %{with_modular_daemons}
-%libvirt_daemon_systemd_post_inet virtproxyd
+# Since this was split into a different package, a transparent update for the
+# virtproxyd units could actually disable an already configured ones
+# (e.g. virtproxyd-tls.socket) as %systemd_post runs `systemctl preset` if this
+# is an installation (and is skipped on update).  So skip this step for those
+# that need an extra setup to work since they will most likely not be preset to
+# enabled, but that is up to the point of the distribution.
+%libvirt_daemon_systemd_post virtproxyd
 %endif
 
 %preun daemon-proxy
-- 
2.41.0