#!/bin/sh

# needrestart - Restart daemons after library updates.
#
# Authors:
#   Thomas Liske <thomas@fiasko-nw.net>
#
# Copyright Holder:
#   2013 - 2018 (C) Thomas Liske [http://fiasko-nw.net/~thomas/]
#
# License:
#   This program is free software; you can redistribute it and/or modify
#   it under the terms of the GNU General Public License as published by
#   the Free Software Foundation; either version 2 of the License, or
#   (at your option) any later version.
#

# Restart dbus and affiliated services under systemd using a procedure
# suggested by @Vladimir-csp in github issue #44.

# enable xtrace if we should be verbose
if [ "$NR_VERBOSE" = '1' ]; then
    set -x
fi

# check if there is a Display Manager running
STATE_DM=$(systemctl show display-manager --property=ActiveState)

# prepare well-known list of services requiring restart after restarting D-Bus
RESTART_CHK="NetworkManager.service"
RESTART_SVC="systemd-logind.service systemd-journald.service"
for svc in $RESTART_CHK; do
    if [ "$(systemctl show $svc --property=ActiveState)" = 'ActiveState=active' ]; then
	RESTART_SVC="$RESTART_SVC $svc"
    fi
done

# stop Display Manager if running
if [ "$STATE_DM" = 'ActiveState=active' ]; then
    systemctl stop display-manager.service
fi

# restard D-Bus
systemctl restart dbus.service

# reexec systemd
systemctl daemon-reexec

# restart daemons that directly depend on D-Bus
systemctl restart $RESTART_SVC

# start Display Manager again
if [ "$STATE_DM" = 'ActiveState=active' ]; then
    systemctl start display-manager.service
fi