Install systemd service file if systemd is available

init/Makefile.am

@@ -0,0 +1,6 @@
+
+SUBDIRS =
+
+if HAVE_SYSTEMD
+  SUBDIRS += systemd
+endif

init/systemd/Makefile.am

@@ -0,0 +1,8 @@
+
+EXTRA_DIST = strongswan.service.in
+CLEANFILES = strongswan.service
+
+systemdsystemunit_DATA = strongswan.service
+
+strongswan.service : strongswan.service.in
+	sed -e "s:@SBINDIR@:$(sbindir):" $(srcdir)/$@.in > $@

init/systemd/strongswan.service.in

@@ -0,0 +1,10 @@
+[Unit]
+Description=strongSwan IPsec
+After=syslog.target
+
+[Service]
+ExecStart=@SBINDIR@/ipsec start --nofork
+StandardOutput=syslog
+
+[Install]
+WantedBy=multi-user.target