#!/usr/bin/env sh

############################################
# Script for manipulating network settings #
############################################
#
# This is useful for example on Ubuntu.
#
# You need to adapt this script to fit your Linux distribution.
# Keep the script name, and use the same command line arguments.
#
# Make sure that the script path is available from your Profinet application.
# In case of problems, try the script manually from the directory where your
# application is located.

if [ $# -ne 6 ]; then
   echo "Usage: ${0} interfacename ip netmask gateway hostname permanent"
   echo "   where:"
   echo "       interfacename:   Network interface name, for example eth0"
   echo "       ip:              IPv4 address, for example 192.168.0.50"
   echo "       netmask:         Netmask"
   echo "       gateway:         Default gateway"
   echo "       hostname:        Host name, for example my_laptop_3"
   echo "       permanent:       1 if changes are permanent, 0 if temporary"
   exit 1
fi

INTERFACE=$1
IP_ADDRESS=$2
NETMASK=$3
DEFAULT_GATEWAY=$4
HOSTNAME=$5
SET_VALUES_PERMANENTLY=$6

# From a Profinet point of view there is no need to change the
# host name of the Linux machine. The p-net stack will use the
# name as station name internally.
SKIP_SETTING_HOSTNAME=true

echo "Network script for ${INTERFACE}: " \
   "Set IP ${IP_ADDRESS}  " \
   "Netmask ${NETMASK}  " \
   "Gateway ${DEFAULT_GATEWAY}  " \
   "Permanent: ${SET_VALUES_PERMANENTLY}  " \
   "Hostname: ${HOSTNAME}  " \
   "Skip setting hostname: ${SKIP_SETTING_HOSTNAME}"

# There is no need to set the changes permanently,
# as the p-net stack will set the IP parameters on each start.
# You are however free to use it if you like.

if ! ip address flush label $INTERFACE; then
   echo "Failed to flush network interface"
   exit 1
fi

if ! ip address add $IP_ADDRESS/$NETMASK dev $INTERFACE; then
   echo "Failed to set IP address and netmask"
   exit 1
fi

if ! ip link set dev $INTERFACE up; then
   echo "Failed to set network interface up"
   exit 1
fi

if [ "${DEFAULT_GATEWAY}" != "0.0.0.0" ]; then
   if ! ip route add default via $DEFAULT_GATEWAY; then
      echo "Failed to set default gateway"
      exit 1
   fi
else
   echo "No valid default gateway given. Skipping setting default gateway."
fi

if [ "$SKIP_SETTING_HOSTNAME" = false ]; then
   if ! hostname $HOSTNAME; then
      echo "Failed to set hostname to $HOSTNAME"
      hostname_len=${#HOSTNAME}
      if [ $hostname_len -gt 64 ]; then
         echo "The given hostname length is ${hostname_len} characters." \
         "Many Linux systems have a limit of 64 characters. The p-net stack uses" \
         "a longer stationname internally."
      fi
      exit 1
   fi
fi

exit 0