#!/bin/sh

make_resolv_conf() {
  echo search $new_domain_name >/etc/resolv.conf
  for nameserver in $new_domain_name_servers; do
    echo nameserver $nameserver >>/etc/resolv.conf
  done
}

# Must be used on exit.   Invokes the local dhcp client exit hooks, if any.
exit_with_hooks() {
  exit_status=$1
  if [ -x /etc/dhclient-exit-hooks ]; then
    . /etc/dhclient-exit-hooks
  fi
# probably should do something with exit status of the local script
  exit $exit_status
}

# Invoke the local dhcp client enter hooks, if they exist.
if [ -x /etc/dhclient-enter-hooks ]; then
  exit_status=0
  . /etc/dhclient-enter-hooks
  # allow the local script to abort processing of this state
  # local script must set exit_status variable to nonzero.
  if [ $exit_status -ne 0 ]; then
    exit $exit_status
  fi
fi

if [ x$new_network_number != x ]; then
   echo New Network Number: $new_network_number
fi

if [ x$new_broadcast_address != x ]; then
 echo New Broadcast Address: $new_broadcast_address
  new_broadcast_arg="broadcast $new_broadcast_address"
fi
if [ x$old_broadcast_address != x ]; then
  old_broadcast_arg="broadcast $old_broadcast_address"
fi
if [ x$new_subnet_mask != x ]; then
  new_netmask_arg="netmask $new_subnet_mask"
fi
if [ x$old_subnet_mask != x ]; then
  old_netmask_arg="netmask $old_subnet_mask"
fi
if [ x$alias_subnet_mask != x ]; then
  alias_subnet_arg="netmask $alias_subnet_mask"
fi

if [ x$reason = xMEDIUM ]; then
  ifconfig $interface $medium
  ifconfig $interface inet -alias 0.0.0.0 $medium >/dev/null 2>&1
  sleep 1
  exit_with_hooks 0
fi

if [ x$reason = xPREINIT ]; then
  if [ x$alias_ip_address != x ]; then
    ifconfig $interface inet -alias $alias_ip_address > /dev/null 2>&1
    route delete $alias_ip_address 127.0.0.1 > /dev/null 2>&1
  fi
  ifconfig $interface inet 0.0.0.0 netmask 0.0.0.0 \
		broadcast 255.255.255.255 up
  exit_with_hooks 0
fi

if [ x$reason = xARPCHECK ] || [ x$reason = xARPSEND ]; then
  exit_with_hooks 0
fi
  
if [ x$reason = xBOUND ] || [ x$reason = xRENEW ] || \
   [ x$reason = xREBIND ] || [ x$reason = xREBOOT ]; then
  if [ x$old_ip_address != x ] && [ x$alias_ip_address != x ] && \
		[ x$alias_ip_address != x$old_ip_address ]; then
    ifconfig $interface inet -alias $alias_ip_address > /dev/null 2>&1
    route delete $alias_ip_address 127.0.0.1 > /dev/null 2>&1
  fi
  if [ x$old_ip_address != x ] && [ x$old_ip_address != x$new_ip_address ]; then
    ifconfig $interface inet -alias $old_ip_address $medium
    route delete $old_ip_address 127.1 >/dev/null 2>&1
    for router in $old_routers; do
      route delete default $router >/dev/null 2>&1
    done
    if [ "$old_static_routes" != "" ]; then
      set $old_static_routes
      while [ $# -gt 1 ]; do
	route delete $1 $2
	shift; shift
      done
    fi
    arp -n -a | sed -n -e 's/^.*(\(.*\)) at .*$/arp -n -d \1/p' |sh
  fi
  if [ x$old_ip_address = x ] || [ x$old_ip_address != x$new_ip_address ] || \
     [ x$reason = xBOUND ] || [ x$reason = xREBOOT ]; then
    ifconfig $interface inet $new_ip_address $new_netmask_arg \
					$new_broadcast_arg $medium
    route add $new_ip_address 127.1 >/dev/null 2>&1
    for router in $new_routers; do
      route add default $router >/dev/null 2>&1
    done
    if [ "$new_static_routes" != "" ]; then
      set $new_static_routes
      while [ $# -gt 1 ]; do
	route add $1 $2
	shift; shift
      done
    fi
  fi
  if [ x$new_ip_address != x$alias_ip_address ] && [ x$alias_ip_address != x ];
   then
    ifconfig $interface inet alias $alias_ip_address $alias_subnet_arg
    route add $alias_ip_address 127.0.0.1
  fi
  make_resolv_conf
  exit_with_hooks 0
fi

if [ x$reason = xEXPIRE ] || [ x$reason = xFAIL ]; then
  if [ x$alias_ip_address != x ]; then
    ifconfig $interface inet -alias $alias_ip_address > /dev/null 2>&1
    route delete $alias_ip_address 127.0.0.1 > /dev/null 2>&1
  fi
  if [ x$old_ip_address != x ]; then
    ifconfig $interface inet -alias $old_ip_address $medium
    route delete $old_ip_address 127.1 >/dev/null 2>&1
    for router in $old_routers; do
      route delete default $router >/dev/null 2>&1
    done
    if [ "$old_static_routes" != "" ]; then
      set $old_static_routes
      while [ $# -gt 1 ]; do
	route delete $1 $2
	shift; shift
      done
    fi
    arp -n -a | sed -n -e 's/^.*(\(.*\)) at .*$/arp -n -d \1/p' \
						|sh >/dev/null 2>&1
  fi
  if [ x$alias_ip_address != x ]; then
    ifconfig $interface inet alias $alias_ip_address $alias_subnet_arg
    route add $alias_ip_address 127.0.0.1
  fi
  exit_with_hooks 0
fi

if [ x$reason = xTIMEOUT ]; then
  if [ x$alias_ip_address != x ]; then
    ifconfig $interface inet -alias $alias_ip_address > /dev/null 2>&1
    route delete $alias_ip_address 127.0.0.1 > /dev/null 2>&1
  fi
  ifconfig $interface inet $new_ip_address $new_netmask_arg \
					$new_broadcast_arg $medium
  sleep 1
  if [ "$new_routers" != "" ]; then
    set $new_routers
    if ping -q -c 1 -w 1 $1; then
      if [ x$new_ip_address != x$alias_ip_address ] && \
			[ x$alias_ip_address != x ]; then
	ifconfig $interface inet alias $alias_ip_address $alias_subnet_arg
	route add $alias_ip_address 127.0.0.1
      fi
      route add $new_ip_address 127.1 >/dev/null 2>&1
      for router in $new_routers; do
	route add default $router >/dev/null 2>&1
      done
      set $new_static_routes
      while [ $# -gt 1 ]; do
	route add $0 $1
	shift; shift
      done
      make_resolv_conf
      exit_with_hooks 0
    fi
  fi
  ifconfig $interface inet -alias $new_ip_address $medium
  for router in $old_routers; do
    route delete default $router >/dev/null 2>&1
  done
  if [ "$old_static_routes" != "" ]; then
    set $old_static_routes
    while [ $# -gt 1 ]; do
      route delete $1 $2
      shift; shift
    done
  fi
  arp -n -a | sed -n -e 's/^.*(\(.*\)) at .*$/arp -n -d \1/p' \
							|sh >/dev/null 2>&1
  exit_with_hooks 1
fi

exit_with_hooks 0