#!/bin/sh

# container-tools - Manage systemd-nspawn containers
# Copyright (C) 2014-2017 Daniel Baumann <daniel.baumann@open-infrastructure.net>
#
# This program 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.
#
# This program 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 this program.  If not, see <http://www.gnu.org/licenses/>.

set -e

COMMAND="$(basename ${0})"

HOOKS="/etc/container-tools/hooks"
MACHINES="/var/lib/machines"

Parameters ()
{
	GETOPT_LONGOPTIONS="name:,"
	GETOPT_OPTIONS="n:,"

	PARAMETERS="$(getopt --longoptions ${GETOPT_LONGOPTIONS} --name=${COMMAND} --options ${GETOPT_OPTIONS} --shell sh -- ${@})"

	if [ "${?}" != "0" ]
	then
		echo "'${COMMAND}': getopt exit" >&2
		exit 1
	fi

	eval set -- "${PARAMETERS}"

	while true
	do
		case "${1}" in
			-n|--name)
				NAME="${2}"
				shift 2
				;;

			--)
				shift 1
				break
				;;

			*)
				echo "'${COMMAND}': getopt error" >&2
				exit 1
				;;
		esac
	done
}

Usage ()
{
	echo "Usage: container ${COMMAND} -n|--name NAME" >&2
	exit 1
}

Parameters "${@}"

if [ -z "${NAME}" ]
then
	Usage
fi

if [ ! -e "${MACHINES}/${NAME}" ]
then
	echo "'${NAME}': no such container" >&2
	exit 1
fi

STATE="$(machinectl show ${NAME} 2>&1 | awk -F= '/^State=/ { print $2 }')"

case "${STATE}" in
	running)
		;;

	*)
		echo "'${NAME}': container is not running" >&2
		exit 1
		;;
esac

LEADER="$(machinectl status ${NAME} | awk '/Leader: / { print $2 }')"

# Pre hooks
for FILE in "${HOOKS}/pre-${COMMAND}".* "${HOOKS}/${NAME}.pre-${COMMAND}"
do
	if [ -x "${FILE}" ]
	then
		"${FILE}"
	fi
done

# Run
if [ -e "${MACHINES}/${NAME}/usr/bin/container-nsenter" ]
then
	OPTIONS="/usr/bin/container-nsenter"
else
	OPTIONS=""
fi

nsenter --target ${LEADER} --mount --uts --ipc --net --pid --root --wd=/root ${OPTIONS}

# Post hooks
for FILE in "${HOOKS}/post-${COMMAND}".* "${HOOKS}/${NAME}.post-${COMMAND}"
do
	if [ -x "${FILE}" ]
	then
		"${FILE}"
	fi
done