#!/bin/bash

function printHelp 
{
  ( 
    echo "$*"
    echo ""
    echo "Usage: $0 [-n] <filename>"
    echo "" 
    echo "  Filters the output of mksnapshot and filters it to show the results"
    echo "  of the backup."
    echo ""
    echo "Options:"
    echo "-n: Disable tailing and exit as soon as the end of the file has been"
    echo "    reached"
    echo ""
  ) 1>&2
  exit 1
}

tailopts="-f"
while [[ $1 = -* ]]
do
  case "$1" in
    -n) tailopts=""
        ;;
    *)  printHelp "Unknown option '$1'"
        ;;
  esac
  shift
done

if [[ $# -ne 1 ]]
then
  printHelp
fi

if [[ ! -r "$1" ]]
then
  printHelp "Could not read '$1'" 
fi

tail -n +0 $tailopts "$1" | grep -e '\*.*Backup.*starting' \
     -e '\*.*Backup.*finished' \
     -e '\*.*OK' \
     -e '\*.*WARNING'