mmdebstrap/tests/pivot_root

#!/bin/sh
set -eu
export LC_ALL=C.UTF-8
export SOURCE_DATE_EPOCH={{ SOURCE_DATE_EPOCH }}
trap "rm -f /tmp/chroot1.tar /tmp/chroot2.tar /tmp/chroot3.tar /tmp/mmdebstrap" EXIT INT TERM

if [ ! -e /mmdebstrap-testenv ]; then
	echo "this test modifies the system and should only be run inside a container" >&2
	exit 1
fi

if [ "$(id -u)" -eq 0 ] && ! id -u user > /dev/null 2>&1; then
	adduser --gecos user --disabled-password user
fi

prefix=
[ "$(id -u)" -eq 0 ] && [ "{{ MODE }}" != "root" ] && prefix="runuser -u user --"

MMDEBSTRAP=
[ -e /usr/bin/mmdebstrap ] && MMDEBSTRAP=/usr/bin/mmdebstrap
[ -e ./mmdebstrap ] && MMDEBSTRAP=./mmdebstrap

$prefix {{ CMD }} --mode={{ MODE }} --variant=apt \
	--include=mount \
	{{ DIST }} /tmp/chroot1.tar {{ MIRROR }}

if [ {{ MODE }} = "unshare" ]; then
	# calling pivot_root in root mode does not work for mysterious reasons:
	# pivot_root: failed to change root from `.' to `mnt': Invalid argument
	$prefix {{ CMD }} --mode={{ MODE }} --variant=apt --include=mount \
		--customize-hook="upload $MMDEBSTRAP /$MMDEBSTRAP" \
		--customize-hook='chmod +x "$1"/'"$MMDEBSTRAP" \
		--customize-hook='mount -o rbind "$1" /mnt && cd /mnt && /sbin/pivot_root . mnt' \
		--customize-hook='unshare -U echo nested unprivileged unshare' \
		--customize-hook="/$MMDEBSTRAP"' --mode=unshare --variant=apt --include=mount {{ DIST }} /tmp/chroot3.tar {{ MIRROR }}' \
		--customize-hook='copy-out /tmp/chroot3.tar /tmp' \
		--customize-hook='rm "$1/'"$MMDEBSTRAP"'"' \
		--customize-hook='umount -l mnt sys' \
		{{ DIST }} /tmp/chroot2.tar {{ MIRROR }}

		cmp /tmp/chroot1.tar /tmp/chroot2.tar
		cmp /tmp/chroot1.tar /tmp/chroot3.tar
		rm /tmp/chroot2.tar /tmp/chroot3.tar
fi

$prefix {{ CMD }} --mode={{ MODE }} --variant=apt --include=mount \
	--customize-hook="upload $MMDEBSTRAP /$MMDEBSTRAP" \
	--customize-hook='chmod +x "$1"/'"$MMDEBSTRAP" \
	--chrooted-customize-hook="/$MMDEBSTRAP"' --mode=unshare --variant=apt --include=mount {{ DIST }} /tmp/chroot3.tar {{ MIRROR }}' \
	--customize-hook='copy-out /tmp/chroot3.tar /tmp' \
	--customize-hook='rm "$1/'"$MMDEBSTRAP"'"' \
	{{ DIST }} /tmp/chroot2.tar {{ MIRROR }}

cmp /tmp/chroot1.tar /tmp/chroot2.tar
cmp /tmp/chroot1.tar /tmp/chroot3.tar