libraries/libvirt: Added soft_restart() to rc.libvirt

With this patch, "rc.libvirt soft_restart" will kill and restart the
libvirt services without affecting any running virtual machines.
This has been a necessity for the SBo infrastructure given our recent
struggles with libvirt losing dbus connectivity without explanation.

Signed-off-by: Robby Workman <rworkman@slackbuilds.org>

libraries/libvirt/rc.libvirt

@@ -188,6 +188,23 @@ stop_virtlockd() {
   sleep 1
 }
 
+soft_restart() {
+  echo "Soft-restarting libvirt..."
+  if [ ! -f $LIBVIRTD_PIDFILE ];then
+    echo "libvirt is not running..."
+    exit 2
+  fi
+  echo "Stopping libvirtd..."
+  kill -TERM $(cat $LIBVIRTD_PIDFILE)
+  sleep 3
+  stop_virtlogd
+  stop_virtlockd
+  sleep 1
+  start_virtlockd
+  start_virtlogd
+  start_libvirtd
+}
+
 case $1 in
 start)
   start_virtlockd
@@ -208,6 +225,9 @@ restart)
   start_virtlogd
   start_libvirtd
   ;;
+soft_restart)
+  soft_restart
+  ;;
 guests_shutdown)
   guests_shutdown
   ;;
@@ -215,7 +235,7 @@ guests_reboot)
   guests_reboot
   ;;
 *)
-  echo "Usage: $0 (start|stop|restart|guests_shutdown|guests_reboot)"
+  echo "Usage: $0 (start|stop|restart|soft_restart|guests_shutdown|guests_reboot)"
   ;;
 esac