#!/bin/sh
### BEGIN INIT INFO
# Provides:          ulab-gpibserver
# Required-Start:    $local_fs $remote_fs
# Required-Stop:     $local_fs $remote_fs
# Should-Start:      console-screen kbd acpid hal krb5-kdc nis
# Should-Stop:       console-screen kbd
# Default-Start:     2 3 4 5
# Default-Stop:      0 1 6
# Short-Description: uLab GPIB Instrumentation Server
# Description:       uLab GPIB Instrumentation Server
### END INIT INFO
# /etc/init.d/ulab-gpibserver: start or stop the uLab GPIB Instrumentation Server
#
# description: uLab GPIB Instrumentation Server
#

. /lib/lsb/init-functions

set -e

PATH=/opt/trinity/bin:/usr/bin:/sbin:/usr/sbin:/bin
DAEMON=/opt/trinity/bin/ulab_gpibserver
PIDFILE=/var/run/ulab_gpibserver.pid
UPGRADEFILE=/var/run/ulab_gpibserver.upgrade

DESC="uLab GPIB Instrumentation Server"

# If we upgraded the daemon, we can't use the --exec argument to
# start-stop-daemon since the inode will have changed.  The risk here is that
# in a situation where the daemon died, its pidfile was not cleaned up, and
# some other process is now running under that pid, start-stop-daemon will send
# signals to an innocent process.  However, this seems like a corner case.
# C'est la vie!
if [ -e $UPGRADEFILE ]; then
  SSD_ARGS="--pidfile $PIDFILE --startas $DAEMON"
else
  SSD_ARGS="--pidfile $PIDFILE --exec $DAEMON"
fi

stillrunning () {
  if expr "$(cat /proc/$DAEMONPID/cmdline 2> /dev/null)" : "$DAEMON" > /dev/null 2>&1; then
    true
  else
    # if the daemon does not remove its own pidfile, we will
    rm -f $PIDFILE $UPGRADEFILE
    false
  fi;
}

case "$1" in
  start)
    log_action_begin_msg "Starting $DESC"
    if start-stop-daemon --background --start --make-pidfile --quiet $SSD_ARGS -- $ARG; then
      log_action_end_msg 0
    else
      log_warning_msg "already running"
      log_action_end_msg 0
    fi
  ;;

  restart)
    /etc/init.d/ulab-gpibserver stop
    if [ -f $PIDFILE ]; then
      if stillrunning; then
        exit 1
      fi
    fi
    /etc/init.d/ulab-gpibserver start
  ;;

  reload)
    log_action_begin_msg "Reloading $DESC"
    if start-stop-daemon --stop --signal 1 --quiet $SSD_ARGS; then
      log_action_end_msg 0
    else
      log_failure_msg "not running"
      log_action_end_msg 1
    fi
  ;;

  force-reload)
    /etc/init.d/ulab-gpibserver reload
  ;;

  stop)
    log_action_begin_msg "Stopping $DESC"
    if [ ! -f $PIDFILE ]; then
      log_failure_msg "Not running ($PIDFILE not found)"
      log_action_end_msg 0
      exit 0
    else
      if start-stop-daemon --stop --quiet $SSD_ARGS; then
        log_action_end_msg 0
      else
        log_failure_msg "not running"
        log_action_end_msg 1
      fi
    fi
  ;;

  *)
    echo "Usage: /etc/init.d/ulab-gpibserver {start|stop|restart|reload|force-reload}"
    exit 1
    ;;
esac

exit 0