RPM packaging polish

Instead of hand-rolling our own systemd integration, we can rely on RPM
macros maintained for us. This results in the following changes in the
main package's scriptlets:

    --- scripts.old	2019-02-14 10:50:21.039974337 +0100
    +++ scripts.new	2019-02-14 10:49:24.649144061 +0100
    @@ -12,14 +12,24 @@

     exit 0
     postinstall scriptlet (using /bin/sh):
    -/bin/systemctl daemon-reload >/dev/null 2>&1 || :
    -chown varnishlog:varnish /var/log/varnish/
     /sbin/ldconfig
    +
    +if [ $1 -eq 1 ] ; then
    +        # Initial installation
    +        systemctl preset varnish varnishncsa >/dev/null 2>&1 || :
    +fi
     preuninstall scriptlet (using /bin/sh):
    -if [ $1 -lt 1 ]; then
    -  # Package removal, not upgrade
    -  /bin/systemctl --no-reload disable varnish.service > /dev/null 2>&1 || :
    -  /bin/systemctl stop varnish.service > /dev/null 2>&1 || :
    -  /bin/systemctl stop varnishncsa.service > /dev/null 2>&1 || :
    +
    +if [ $1 -eq 0 ] ; then
    +        # Package removal, not upgrade
    +        systemctl --no-reload disable varnish varnishncsa > /dev/null 2>&1 || :
    +        systemctl stop varnish varnishncsa > /dev/null 2>&1 || :
     fi
    -postuninstall program: /sbin/ldconfig
    +postuninstall scriptlet (using /bin/sh):
    +/sbin/ldconfig
    +
    +systemctl daemon-reload >/dev/null 2>&1 || :
    +if [ $1 -ge 1 ] ; then
    +        # Package upgrade, not uninstall
    +        systemctl try-restart varnish varnishncsa >/dev/null 2>&1 || :
    +fi

The only major change is that the varnish and varnishncsa services will
be restarted during a varnish upgrade. This is needed because otherwise
reloading a VCL that uses vmod_std after the upgrade (and without
restarting) would fail because the running varnishd wouldn't recognize
the shared object's expected ABI.

One unrelated change is the handling of /var/log/varnish/ ownership. As
it was done until now a fresh install would yield a corrupted package:

    $ rpm --verify varnish
    .....UG..    /var/log/varnish

Since we already create the users and group before installing the files,
we can already ask RPM to chown the directory itself.

redhat/varnish.spec

@@ -25,11 +25,7 @@ BuildRequires: systemd-units
 
 Requires: gcc
 Requires: logrotate
-
-Requires(post):   systemd-units
-Requires(post):   systemd-sysv
-Requires(preun):  systemd-units
-Requires(postun): systemd-units
+%systemd_requires
 
 Provides:  varnish-libs%{?_isa} = %{version}-%{release}
 Provides:  varnish-libs = %{version}-%{release}
@@ -118,13 +114,13 @@ rm -rf %{buildroot}
 %{_libdir}/*.so.*
 %{_libdir}/%{name}
 %{_var}/lib/varnish
-%{_var}/log/varnish
 %{_mandir}/man1/*.1*
 %{_mandir}/man3/*.3*
 %{_mandir}/man7/*.7*
 %{_docdir}/%{name}/
 %{_datadir}/%{name}
 %{_unitdir}/*
+%attr(-,varnishlog,varnish) %{_var}/log/varnish
 %exclude %{_datadir}/%{name}/vmodtool*
 %exclude %{_datadir}/%{name}/vsctool*
 %doc README*
@@ -163,21 +159,17 @@ exit 0
 
 
 %post
-/bin/systemctl daemon-reload >/dev/null 2>&1 || :
-chown varnishlog:varnish /var/log/varnish/
 /sbin/ldconfig
+%systemd_post varnish varnishncsa
 
 
 %preun
-if [ $1 -lt 1 ]; then
-  # Package removal, not upgrade
-  /bin/systemctl --no-reload disable varnish.service > /dev/null 2>&1 || :
-  /bin/systemctl stop varnish.service > /dev/null 2>&1 || :
-  /bin/systemctl stop varnishncsa.service > /dev/null 2>&1 || :
-fi
+%systemd_preun varnish varnishncsa
 
 
-%postun -p /sbin/ldconfig
+%postun
+/sbin/ldconfig
+%systemd_postun_with_restart varnish varnishncsa
 
 
 %changelog