#!/bin/sh
#
# $Id: etcbackup.sh 216 2010-11-06 16:38:30Z rick $
# Poor mans configuration backup. Only save the new backup if configuration
# content changes
#
# Rick van der Zwet <info@rickvanderzwet.nl>

TAG=`date "+%Y%m%d"`

BACKUPROOT=/usr/local/backup/config
TARGET=$BACKUPROOT/etc-$TAG.tar

# Check for last backup file
mkdir -p $BACKUPROOT
LAST=`ls -t1 /usr/local/backup/config/etc-*.tar | head -1`

if [ "$LAST" = "$TARGET" ]; then
  echo "# Error file '$TARGET' does already exists" 1>&2
  exit 1
fi

# Create new backup file
tar -C / -cf $TARGET etc usr/local/etc 2>&1

# If old file this exists, only keep new files if changes exists
if [ -n "$LAST" ]; then
  PREV_MD5=`md5 -q $LAST`
  NEW_MD5=`md5 -q $TARGET`
  if [ "$PREV_MD5" = "$NEW_MD5" ]; then
    rm $TARGET
  fi
fi