#!/bin/sh
#
# Set unique host name rp-xxxxxx based on MAC address.
#

start() {

    # Read "ethaddr" variable from U-Boot environment in EEPROM.
    #
    # Environment starts at address 0x1800 and is 1024 bytes long.
    # The environment consists of "key=value" pairs, separated by 0x00 bytes.
    #
    ethaddr_pair="$( dd if=/sys/bus/i2c/devices/0-0050/eeprom bs=1k skip=6 count=1 status=none | tr '\000' '\n' | grep ^ethaddr= )"

    if [ -z "${ethaddr_pair}" ]; then
        echo "ERROR: ethaddr not found in EEPROM enviroment" >&2
        exit 1
    fi

    ethaddr="${ethaddr_pair#ethaddr=}"

    suffix="$( echo $ethaddr | cut -d: -f 4- | tr -d : | tr ABCEDF abcdef )"
    hostname="rp-${suffix}"

    echo "Setting hostname ${hostname}"

    echo $hostname > /etc/hostname
    /bin/hostname -F /etc/hostname

    grep -v '^127\.0\.1\.1' /etc/hosts > /etc/hosts.new
    echo "127.0.1.1 $hostname" >>/etc/hosts.new
    mv /etc/hosts.new /etc/hosts
}

case "$1" in
  start)
    start
    ;;
  stop|restart|reload)
    ;;
  *)
    echo "Usage: $0 start"
    exit 1
esac