Comment # 31 on bug 968405 from Egbert Eich

(In reply to Dominique Leuenberger from comment #26)
> 
> %service_del_postun is defined in two places:
> /etc/rpm/macros.systemd
> /usr/lib/rpm/macros

Ah, I didn't even notice that. It would be nice if we had the chance to
consolidate this in the process.

> Looking at xdm, you got the one from /etc/rpm/macros.systemd (thus, the
> entire discussion so far stays true)

Right.

> > Besides this - you are talking about 'update' - how do you distinguish
> > 'update' from 'removal' using the '%pre/%postun' scriptlets?
> > This may not even matter for the case at hand but since you are looking at
> > the 'general' case, you may have to.
> 
> /etc/rpm/macros.systemd's %service_del_postun expands to:
> # On uninstall, tell systemd to reload its unit files
> %service_del_postun()                                                       
> \
> test -n "$FIRST_ARG" || FIRST_ARG="$1"                                      
> \
> if [ "$FIRST_ARG" -ge 1 ]; then                                             
> \
>         # Package upgrade, not uninstall                                    
> \
>         if [ -x /usr/bin/systemctl ]; then                                  
> \
>                 /usr/bin/systemctl daemon-reload || :                       
> \
>                 ( %_restart_check_systemctl %{?*} || : )                    
> \
>         fi                                                                  
> \
> else # package uninstall                                                    
> \
>         for service in %{?*} ; do                                           
> \
>                 sysv_service="${service%.*}"                                
> \
>                 rm -f "/var/lib/systemd/migrated/$sysv_service" || :        
> \
>         done                                                                
> \
>         if [ -x /usr/bin/systemctl ]; then                                  
> \
>                 /usr/bin/systemctl daemon-reload || :                       
> \
>         fi                                                                  
> \
> fi                                                                          
> \
> %{nil}
> 
> 
> Updated vs uninstall is handled in the script.

Ok, I now faintly remember that there is an argument passed to the %pre/%postun
scripts. 

> 
> for reference, %_restart_check_systemctl expands to:
> 
> %_restart_check_systemctl                                                   
> \
>         test -f /etc/sysconfig/services && . /etc/sysconfig/services        
> \
>         test "$YAST_IS_RUNNING" = instsys       && exit 0                   
> \
>         test "$DISABLE_RESTART_ON_UPDATE" = yes && exit 0                   
> \
>         /usr/bin/systemctl try-restart %{nil}
> 
> And here lies the problem - export DUSABLE_RESTART_ON_UPDATE=yes (as set by
> xdm.spec) is overwritten by sourcing /etc/sysconfig/services and the system
> default being taken into account - resulting in the issue we now discuss /
> hopefully try to fix.

Which I mentioned already more than once. So agreed.