#!/bin/sh

#    How to use rsync to approximate 'timemachine'. 
# WE do not support hard links on directories, so we can't be quite as
# efficient as Apple's TimeMachine.
# Note: use quotes throughout as filenames may (do) include spaces.
# Note: drive (ON OS X) should be mounted with uids enabled..
#      sudo /usr/sbin/vsdbutil -a /Volumes/${VOLUME_NAME}
# Note: entries can also be put in /etc/fstab to affect mounting
#     but in OS X 10.5 or later one should use 'vifs'.
# adjust to fit your environent.
# This is setup to run on OS-X 10.4 (before timemachine).
# It has also run on FreeBSD.
#

ROOT_VOLUME="Macintosh HD"
APPDIR="Backups.backupdb"
ORIGINALBASE="/"
EXCLUDEFILE="/Volumes/MyBook2-1T/exclude-from-backup"

BACKUPBASE="/Volumes/MyBook2-1T"
BACKUPDIR="${BACKUPBASE}/${APPDIR}"
BACKUPHOSTDIR="${BACKUPDIR}/`hostname -s`"

BACKUPFILENAME=`date +"%Y-%m-%d-%H%M%S"`
LATESTLINK="${BACKUPHOSTDIR}/Latest"
BACKUPNAME="${BACKUPHOSTDIR}/${BACKUPFILENAME}"
TEMPNAME="${BACKUPNAME}.inprogress"
CREATENAME="${TEMPNAME}/${ROOT_VOLUME}"


if [ -d "${BACKUPNAME}" ]
then
  echo "ERROR: Backup ${BACKUPNAME} already exists. Exiting."
  exit 1
fi

mkdir -p "${CREATENAME}"

if [ -e "${LATESTLINK}" ]
then
  rsync -xaHPR "--exclude-from=${EXCLUDEFILE}" "--link-dest=../../Latest/${ROOT_VOLUME}/" "${ORIGINALBASE}" "${CREATENAME}"
else
  rsync -xaHPR "--exclude-from=${EXCLUDEFILE}" "${ORIGINALBASE}" "${CREATENAME}"
fi

if  [ $? = 0 ]
then
    touch "${TEMPNAME}/.com.apple.TMCheckpoint"
    mv "${TEMPNAME}" "${BACKUPNAME}"
    rm "${LATESTLINK}"
    ln -sf "${BACKUPFILENAME}" "${LATESTLINK}"
else
    echo " Backup  to ${BACKUPNAME} FAILED"
    mv "${TEMPNAME}" "${BACKUPNAME}.FAILED"
    exit 1
fi