gz2xz.sh

#!/bin/bash

set -o errexit
set -o nounset
set -o pipefail

umask 077

readonly checksum="sha1sum"

readonly dir="$(dirname ${1})"
readonly gzf="$(basename ${1})"
readonly xzf="$(basename ${gzf} .gz).xz"

pushd ${dir} >/dev/null

sum1=$(gzip -dc ${gzf} | tee >(xz > ${xzf}) | ${checksum})
sum2=$(xz -dc ${xzf} | ${checksum})

chown --reference=${gzf} ${xzf}
chmod --reference=${gzf} ${xzf}

if [[ "${sum1}" == "${sum2}" ]]; then
  rm -f ${gzf}
fi

popd >/dev/null