source: MondoRescue/branches/3.3/mindi-busybox/examples/var_service/zcip_if/zcip_handler

#!/bin/sh
# executed by zcip
# parameters: $1 and environment
# $1 is:
#
# init: zcip starts. Environment:
# interface=eth0
#
# config: Address is obtained.
# interface=eth0
# ip=169.254.a.b
#
# deconfig: Conflict or link went down.
# interface=eth0

service=${PWD##*/}
file_ipconf="$service.ipconf"
dir_ipconf="/var/run/service/fw"

exec >/dev/null
#exec >>"$0.out"  #debug
exec 2>&1

echo "`date`: Params: $*"

if test x"$1" != x"config"; then
    # Reconfigure network with this interface disabled
    echo "Deconfiguring"
    rm "$file_ipconf"
    rm "$dir_ipconf/$file_ipconf"
    sv u /var/service/fw
    exit
fi

# "config": we've got the address
# Record information for e.g. dhcp_$IF_pinger service
env >"env.out"

./convert2ipconf "$file_ipconf"
# Reconfigure routing and firewall if needed
diff --brief "$file_ipconf" "$dir_ipconf/$file_ipconf" >/dev/null 2>&1
if test $? != 0; then
    echo "Reconfiguring fw"
    mkdir -p "$dir_ipconf" 2>/dev/null
    cp "$file_ipconf" "$dir_ipconf/$file_ipconf"
    sv u /var/service/fw
fi