#!/bin/sh
# Incremental backup using rsync(1).

[ "$USER" = root ] || exec sudo "$0" "$@"

backup() {
	date=$(date +%Y%m%d_%H%M%S)
	last=$(rsync --list-only "$dest/" 2>/dev/null | cut -b 47- | tail -1)

	case $last in
	([12]*) opt_link=--link-dest=../$last;;
	(*) opt_link=;;
	esac

	rsync -HSxa$optv --exclude-from=$ignore $opt_link / /boot "$dest/$date"
}

dest=/.history
ignore=/etc/backup/ignore

while getopts :d:i:nv opt; do
	case $opt in
	(d) dest="$OPTARG" ;;
	(i) ignore="$OPTARG" ;;
	(n|v) optv="$opt$optv" ;;
	(*) echo "Usage: $0 [-nv] [-d [host:]dir] [clean|diff]"; exit 1 ;;
	esac
done
shift $((OPTIND - 1))

[ "$1" ] && cmd=$1 && shift || cmd=""
case $cmd in
(""|save) backup ;;
(clean) exec backup-clean ${optv+-$optv} "$dest";;
(diff) exec diffdir "$@";;
esac