Spec file bits for packages migrating from sysv to systemd, for cases
where the daemon is allowed to autostart, and/or when the old
package's %postun will not successfully restart the daemon on
migration upgrades.

%global migrfile %{_var}/run/systemd-migrate_%{name}-%{version}-%{release}.%{_arch}

BuildRequires:  systemd-units
Requires(pre):  systemd-sysv chkconfig
Requires(post): systemd-units
Requires(preun): systemd-units
Requires(postun): systemd-units

%pre
rm -f %{migrfile} &>/dev/null
if [ $1 -gt 1 ] && [ ! -e %{_unitdir}/FOO.service ] && \
   [ -e %{_initddir}/FOO ] ; then
    systemd-sysv-convert --save FOO &>/dev/null
    chkconfig --del FOO &>/dev/null
    touch %{migrfile} &>/dev/null || :
fi

%post
if [ $1 -eq 1 ] ; then
    systemctl daemon-reload &>/dev/null || :

    # If the service is allowed to autostart:
    systemctl --no-reload enable FOO.service &>/dev/null || :
fi

%preun
if [ $1 -eq 0 ] ; then
    systemctl --no-reload disable FOO.service &>/dev/null
    systemctl stop FOO.service &>/dev/null || :
fi

%postun
systemctl daemon-reload &>/dev/null
[ $1 -gt 0 ] && systemctl try-restart FOO.service &>/dev/null || :

%triggerpostun -- %{name}
if [ $1 -gt 0 ] && [ -e %{migrfile} ] ; then

    systemctl daemon-reload &>/dev/null

    # If the service is allowed to autostart:
    systemctl --no-reload enable FOO.service &>/dev/null

    # If the old package uses sysv init script directly for
    # try-restart in its %postun (which will fail if the init script
    # is no longer installed) instead of "service", or does not do the
    # try-restart at all, we take care of that here:
    systemctl try-restart FOO.service &>/dev/null
    
fi
rm -f %{migrfile} &>/dev/null || :