#! /bin/bash

cleanup() {
    umount -R chroot
}

set -ex

mkdir -p chroot/{dev,proc,sys,output} output

mount --bind chroot chroot
mount --bind output chroot/output
mount --bind /dev   chroot/dev
mount --bind /proc  chroot/proc
mount --bind /sys   chroot/sys

trap cleanup EXIT

chroot chroot "$@"