#! /bin/sh -x
# -*- sh -*-

# $Header$
# $Log$

# This script runs as user root, so that it has permission to overwrite
# /etc/dhcpd.conf and also to restart the dhcp server.

HOME="/root"
MNT_DIR="/var/ipsetup"
# MNT_CMD="${HOME}/bin/mountexcel"
# UMOUNT="/bin/umount"
TMP_DIR="${HOME}/tmp"
MAKE_DHCP="/root/bin/make-dhcpd-conf"
MAKE_DNS="/root/bin/make-dns-db"
PATH=$PATH:/usr/local/bin:/root/bin
DNSDIR=/var/named

#  if mount | grep ipsetup >& /dev/null
#  then
#      set ${MNT_DIR}/*.txt
#      if [ ! -f $1 ]
#      then
#          ${UMOUNT} ${MNT_DIR} >& /dev/null
#          ${MNT_CMD}
#      fi
#  else
#      ${MNT_CMD}
#  fi
#  set ${MNT_DIR}/*.txt
#  if [ ! -f $1 ]
#  then
#      echo "${MNT_DIR} seems to be mounted, but no file *.txt!"
#      exit 3
#  fi

# If the Excel spreadheet file or the text hosts file we've been using
# is newer than the configuration file, then
# rebuild configuration.
EXCEL_FILE=${MNT_DIR}/ict-mac-ip-address-computer-list.xls
ORIG_HF=${DNSDIR}/hosts/hosts
HOSTFILE=${DNSDIR}/hosts/ict-mac-ip-address-computer-list-text.txt
for file in $EXCEL_FILE $ORIG_HF
do
    if [ "$file" -nt "/etc/dhcpd.conf" ]
    then
        parse-excel.pl $EXCEL_FILE > $HOSTFILE
        cat $ORIG_HF >> $HOSTFILE
        if ${MAKE_DHCP} $HOSTFILE > ${TMP_DIR}/dhcpd.conf
        then
            echo "/bin/cp -a ${TMP_DIR}/dhcpd.conf /etc/dhcpd.conf"
            /bin/cp -a ${TMP_DIR}/dhcpd.conf /etc/dhcpd.conf
            /etc/rc.d/init.d/dhcpd restart
            
            # If the clock on the Windows PC that was used to edit the
            # spreadsheet is set earlier than on this machine, we have a
            # problem where this script continuously updates and restarts
            # the servers every two minutes until the condition that the
            # excel file is newer than the dhcpd.conf file is false.
            # By making them both the same date, we avoid that problem.
            # Actually, to really solve it, we need to make dhcpd.conf
            # have a timestamp >= that of newest text file, not the first one.
            # But as we say in Australia, it's "rough enough for the bush".
            if [ "$file" -nt "/etc/dhcpd.conf" ]
            then
                touch --reference=$file "/etc/dhcpd.conf"
            fi

            cd $DNSDIR
            service named stop
            sleep 5
            ${MAKE_DNS} $HOSTFILE
            rm *.jnl
            service named start
            exit 0
        fi
    fi
done