#!/bin/sh

# full and incremental backup script
# created 07 February 2000
# Based on a script by Daniel O'Callaghan <danny@freebsd.org>
# and modified by Gerhard Mourani <gmourani@videotron.ca>
# modified more by Joel Aufrecht in 2002 for OpenACS servers
#
#########################################################################
#
# Change the variables below to fit your computer/backup

COMPUTER=$HOSTNAME                   # name of this computer
BACKUPUSER=backup                    # username to own the files
BACKUPDIR=/backup                    # where to store the backups
TIMEDIR=$BACKUPDIR/last-full         # where to store time of full backup
TAR=/bin/tar                         # name and location of tar
CHOWN=/bin/chown
CHMOD=/bin/chmod
SCP=/usr/bin/scp
DIRECTORIES="/etc /root /cvsroot /var/qmail/alias /var/log/aolserver /usr/local/aolserver /web/openacs-prod /backup/openacs"

                                     # a list of paths to be backed up

#########################################################################
#
# OTHERHOST is optional.

OTHERHOST=                           # another server, to receive backup 
                                     # files 
                                     # leave blank to skip scp exchange

OTHERUSER=backup                     # the user on the recipient server
                                     # must have silent authentication, ie,
                                     # certificates




###########################################################
# Shouldn't need to change anything below this line

DOW=`date +%a`              # Day of the week e.g. Mon
DOM=`date +%d`              # Date of the Month e.g. 27
DM=`date +%d%b`             # Date and Month e.g. 27Sep
DATE=`date +"%Y-%m-%d"`     # Year, Month, Date, e.g. 20020401

mkdir -p $BACKUPDIR
mkdir -p $TIMEDIR

# On the 1st of the month a permanent full backup is made
# Every Sunday a full backup is made
# The rest of the time an incremental backup is made.
# Each backup has a date-specific filename
#
# if NEWER = "", then tar backs up all files in the directories
# otherwise it backs up files modified since the NEWER date. NEWER
# gets its date from the file written every Sunday.

# Figure out what to do and set variables
case $1 in 
    full)
	TYPE="full"
	NEWER=""
	DELETEOLD=0
	;;
    automatic)
	if [[ $DOM = "01" || ($DOW = "Sun") ]]
	    then
	    TYPE="full"
	    NEWER=""
	    NOW=`date +%Y-%m-%d`
	    echo $NOW> $TIMEDIR/$COMPUTER-full-date
	else
	    TYPE="incremental"
	    NEWER="--newer-mtime `cat $TIMEDIR/$COMPUTER-full-date`"
	fi
	;;
    *)
	echo "Usage: $0 full to force full backup, or $0 automatic to run automated.  All other variables are set in the script."
	exit
	;;
esac

# Do the actual work

for directory in $DIRECTORIES

  do

  # strip directory of slashes when using it in the backup file name
  FULLNAME=$BACKUPDIR/$DATE-$COMPUTER-${directory//\//-}-backup-$TYPE.tar.bz2 
  tar -jcpsh $NEWER --file $FULLNAME $directory
  chown $BACKUPUSER $FULLNAME
  chmod 770 $FULLNAME
  if [[ -n $OTHERHOST ]]
      then scp -oProtocol=2 $FULLNAME $OTHERUSER@$OTHERHOST:$BACKUPDIR
  fi
done