service

#!/bin/sh

PIDFILE='/var/run/dhcp/dhcpd.pid'

start() {
  echo 'Starting ISC-DHCP-SERVER...'

  if [ -f "$PIDFILE" ] && [ ! $(pidof dhcpd) ]; then
    echo 'Stale PID file, removing it.' >&2
    rm "$PIDFILE"
  elif [ ! -f "$PIDFILE" ] && [ $(pidof dhcpd) ]; then
    echo 'Server is already running, but missing PID file.' >&2
    echo "$(pidof dhcpd)" > "$PIDFILE"
    echo 'Created new PID file'
  fi
  if [ ! -f "$PIDFILE" ] && [ ! $(pidof dhcpd) ]; then
    bash -c '/usr/sbin/dhcpd -4 -f -d -cf /etc/dhcp/dhcpd.conf > /var/log/dhcp.log 2>&1 &'
    echo 'Service started' >&2
  else
    echo 'Service is already running.'
  fi
}

stop() {
  echo "Stopping ISC-DHCP-SERVER..."
  if [ ! -f "$PIDFILE" ] || ! kill -0 $(cat "$PIDFILE"); then
    echo 'Service was not running' >&2
    return 1
  else
    kill -15 $(cat "$PIDFILE") && rm -f "$PIDFILE"
    echo 'Service stopped' >&2
  fi
}

case "$2" in
  start)
    start
    ;;
  stop)
    stop
    ;;
  restart)
    stop
    sleep 1
    start
    ;;
  *)
    echo "Usage: $0 isc-dhcp-server {start|stop|restart}"
    exit 1
    ;;
esac

exit 0