#! /bin/sh
# tarbak (Bourne shell script) -- does full/incremental backups using tar
# The files are placed in /var/backup/<Month><year>
# "exclude" statements in the real user's .tarbakrc specify one 
# or more additional files/directories/wildcards to be excluded
#
# Version: 1.4

files="/etc /home /root /var/mail /usr/local /srv /boot/grub"

backup_dir=/var/backup/`date +'%b%Y'`
name_format=`uname -n`_`date +'%b%Y'`

if [ -d $backup_dir ] ; then
  # Directory already exists; assume that the full backup has already been
  # done this month.

  # calculate the number of tarfiles aready in the directory; this 
  # sequence number is one beyond that of the most recent incremental file
  seq=`ls $backup_dir/${name_format}* | wc -l`
  tarfile=${name_format}_`printf %02d $seq`.tar.gz

  # make a backup of the list file just in case it becomes screwed up due to a script error
  cp -p $backup_dir/list $backup_dir/list.bak
else
  # Directory does not exist yet; create it and do a full backup
  mkdir -p $backup_dir
  tarfile=$name_format.tar.gz
fi

# a subcommand embeds a sed script that processes lines from .tarbak
# starting with "exclude" and places them onto the tar command line as
# --exclude options.  (Filenames containing spaces must be quoted; the
# outer 'qstringloop' label/test handles multiple quoted strings on a
# line, whilst the inner 'spaceloop' label/test converts each space
# within such a string to a question mark.)
tar zc -g $backup_dir/list -f $backup_dir/$tarfile \
  --exclude='*~' --exclude=.DS_Store --exclude=.FBCLockFolder --exclude=.gvfs \
  --exclude=.ccache --exclude=.beagle --exclude=.cache \
  --exclude=.xvpics --exclude='#*#' --exclude='.*.sw?' \
  --exclude='/home/*/.mozilla/*/*/Cache*' --exclude='/home/*/.prism/*/*/Cache*' \
  --exclude='/home/*/.mozilla/*/*/*.mfasl' --exclude='/home/*/.mozilla/*/*/history.dat.old' --exclude='/home/*/.mozilla/*/*/*.bak' --exclude='/home/*/.mozilla/*/*/urlclassifier*.sqlite' \
  --exclude='/home/*/.gnome2/epiphany/mozilla/epiphany/Cache' --exclude='/home/*/.java/deployment/cache' \
  --exclude='/home/*/.thumbnails' --exclude='/home/*/.Trash' \
  --exclude='/home/*/.openoffice.org2/user/config/imagecache' \
  --exclude='/home/*/.openoffice.org/3/user/uno_packages' --exclude='/home/*/.openoffice.org2/user/registry/cache' \
  --exclude='/home/*/.kde/share/apps/nepomuk/repository' \
  --exclude='/home/*/.local/share/desktop-couch/.gwibber_messages_design' \
  --exclude=/etc/brltty --exclude=/etc/gconf/gconf.xml.defaults \
  `if [ -f $HOME/.tarbakrc ] ; then sed -n -e "/^exclude/ {" -e :qstringloop -e :spaceloop -e 's/^\([^"]*"[^ "]*\) /\1?/' -e "t spaceloop" -e 's/"\([^"]*\)"/\1/' -e "t qstringloop" -e "s@ \([^/]\)@ $HOME/\1@g" -e "s/ / --exclude=/g" -e 's/^exclude//p' -e "}" $HOME/.tarbakrc ; fi` \
  $files