scratch_build()
{
    echo "$EXTRA_MIRROR" |
    sed 's/[,;]/\n/' |
    su -l -c "/usr/share/ltsp/scripts/gen-ltsp-image $ARCH \"$MIRROR\"" ltspadmin | tar -C "$ROOT" -xf -
}

tar_build()
{
    tar -C "$ROOT" -x${1}f "$CHROOT_IMAGE"
}

cpio_build()
{
    pushd "$ROOT"
    ${1}cat "$CHROOT_IMAGE" | cpio -i -m --no-absolute-filenames -d
    popd
}

case "$MODE" in
    install)
	if [ -n "$CHROOT_IMAGE" -a -r "$CHROOT_IMAGE" ]; then
	    case "$CHROOT_IMAGE" in
		*.tar.gz|*.tgz|*.tar.Z|*.tZ)
		    tar_build z
		    ;;
		*.tar.bz2|*.tbz2|*.tbz)
		    tar_build j
		    ;;
		*.tar)
		    tar_build
		    ;;
		*.cpio)
		    build_cpio
		    ;;
		*.cpio.gz|*.cpio.Z)
		    cpio_build z
		    ;;
		*.cpio.bz2)
		    cpio_build bz
		    ;;
		*)
		    echo "Usupported image file format. Trying buld chroot from scratch." >&2
		    scratch_build
		    ;;
	    esac
	else
	    scratch_build
	fi
        ;;
esac
