backup script wrapper around duplicity backup app

backup.sh

#!/bin/bash
 
# make certain only root and edit this script.
l=($(ls -l `readlink -f $0`))
[ ${l[0]:2:1} != "-" ] && [ "${l[2]}" != "root" ] ||
[ ${l[0]:5:1} != "-" ] && [ "${l[3]}" != "root" ] ||
[ ${l[0]:8:1} != "-" ] && { 
echo -e "Script uses or is called from sudo often.\nOnly root should be able to modify.\n${l[@]}"; 
exit 1;}

usage_self () 
{ 
    echo -en "usage: `basename \"$0\"` ";
    grep '^  *[^ \(\*]*)' $0 | xargs | sed 's/)//g' | sed 's/ +/ /g' | sed 's/ /\|/g' | sed 's/--//g';
    echo "";
    grep -A 30 '^  *[^ \(\*]*)' $0 | egrep -B 1 '^  #' | sed 's/#//' | sed 's/--//g';
    echo ""
}

test $# -lt 2 && usage_self && exit 1

case "$1" in
  show)
  # show <src> [depth] [filter] 
  #			shows status and list of and files from source backup
	$0 status $2
	$0 list $2 $3 $4
  ;;
  status)
	CMD="duplicity collection-status file://$2"
  ;;
  list)
  # list <src> [depth]	list files in source backup
	echo "$3" | egrep -q '^[0-9]+$' && DEPTH=$3 && FILTER=$4
	echo "$4" | egrep -q '^[0-9]+$' && DEPTH=$4 && FILTER=$3
	CMD="duplicity list-current-files file://$2 | awk '{print \$6}' "
	test -n "$FILTER" && CMD="$CMD | egrep \"$FILTER\""
	test -n "$DEPTH" && CMD="$CMD | cut -d'/' -f1-$DEPTH | uniq -c "
  ;;
  restore)
  # restore <src> <dst>	[relpath]
  # restore from src to dst with optional relpath
  # relpath is the same as found from list cmd
	test -n "$4" && RELPATH="$4"
	CMD="duplicity restore "
	test -n "$RELPATH" && CMD="$CMD --file-to-restore \"$4\""
	CMD="$CMD file://$2 $3"
	test -n "$RELPATH" && CMD="$CMD/$RELPATH"
  ;;
  backup)
  # backup <src> <dst>	 
	CMD="sudo duplicity $2 file://$3"
	
  ;;
  *)
	$0 backup $2 $3
  ;;
esac
echo -e "$CMD"
read -p "execute [y]/n? " YN
test "$YN" = "n" || eval "$CMD"