# Functions for setting up isolated file system environments
#
# Copyright (C) 2014  Patrick "P. J." McDermott
#
# This file is part of the ProteanOS Development Kit.
#
# The ProteanOS Development Kit is free software: you can redistribute
# it and/or modify it under the terms of the GNU General Public License
# as published by the Free Software Foundation, either version 3 of the
# License, or (at your option) any later version.
#
# The ProteanOS Development Kit is distributed in the hope that it
# will be useful, but WITHOUT ANY WARRANTY; without even the implied
# warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
# See the GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with the ProteanOS Development Kit.  If not, see
# <http://www.gnu.org/licenses/>.

[ "x${_CHROOT_SM+set}" = 'xset' ] && return 0
_CHROOT_SM=1

use profile

chroot_mount()
{
	local root="${1}"
	local arch=
	local plat=
	local fs=
	local dir=
	local fstype=
	local options=

	arch="$(cat "${root}/etc/proteanos_arch")"
	plat="$(cat "${root}/etc/proteanos_plat")"

	while read fs dir fstype options; do
		[ "x${dir}" = 'x' ] && continue
		mount -t "${fstype}" -o "${options}" "${fs}" "${root}/${dir}"
	done <<-EOF
		$(profile_get_fstab "${arch}" "${plat}")
		EOF
}

chroot_umount()
{
	local root="${1}"
	local arch=
	local plat=
	local fs=
	local dir=
	local fstype=
	local options=

	arch="$(cat "${root}/etc/proteanos_arch")"
	plat="$(cat "${root}/etc/proteanos_plat")"

	while read fs dir fstype options; do
		[ "x${dir}" = 'x' ] && continue
		# umount sometimes complains that the /dev file system is busy.
		# Here's a kludge to try to handle that.  We better make sure
		# bind mounts get unmounted; otherwise, `rm -Rf ${root}` can be
		# painful.
		while ! umount "${root}/${dir}"; do
			sleep 1
		done
	done <<-EOF
		$(profile_get_fstab "${arch}" "${plat}" | sed -n '1!G;h;$p')
		EOF
}

chroot_exec()
{
	local root="${1}"
	shift 1

	chroot_mount "${root}"
	chroot "${root}" "${@}"
	chroot_umount "${root}"
}