function untarz {
  local tarfile=$1
  local root_count=`tar tfz $tarfile | cut -d / -f 1 | uniq | wc -l`

  if [[ $root_count -gt 1 ]]; then
    echo "Warning! The given tarball has more than one root file. File not extracted."
    return 1
  else
    tar xzf $tarfile
  fi
}