#!/bin/sh
# 
#  apt-in-chroot - runs apt in a specified chroot
# 
#  Copyright (C) 2010 Martin Zobel-Helas <zobel@debian.org>
#
#  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 2, 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, write to the Free Software Foundation,
#  Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA.
# 

VALID_CHROOTS="$(/usr/bin/dchroot -l 2>&1 | /usr/bin/awk -F": " '{print $2}' | /usr/bin/tr ' ' '\n')"
VALID_CHROOTS_PARSE="$(/usr/bin/dchroot -l 2>&1 | /usr/bin/awk -F": " '{print $2}' | /bin/sed -e 's/ /|/g')"

usage() {
        bn="`basename "$0"`"
	echo "Usage: $bn <chroot> <apt sub-command> <package>"
	echo ""
	echo "  allowed chroots are ($VALID_CHROOTS_PARSE)"
	echo ""
	echo "  allowed apt sub-commands are:"
	echo "          + install"
	echo "          + remove"
	echo "          + purge"
	echo "          + build-dep"
}


if [ "$#" -lt "3" ]; then
	usage >&2
	exit 1
fi

CHROOT_DIR="/chroot"
CHROOT=$1; shift
APTCMD=$1; shift
PACKAGES=$*


case "$APTCMD" in
install|remove|purge|build-dep)
	# those are the allowed apt sub-commands
	;;
*)
	echo "$APTCMD is not a valid apt sub-command"
	exit 1
	;;
esac

grep -qFx $CHROOT <<< "$VALID_CHROOTS"

RET=$?

if [ "$RET" == "0" ]; then
	# valid chroot
	echo "Will run '/usr/sbin/chroot $CHROOT_DIR/$CHROOT apt-get $APTCMD $PACKAGES'"
	/usr/sbin/chroot $CHROOT_DIR/$CHROOT apt-get $APTCMD $PACKAGES
else
	echo "$CHROOT not in $VALID_CHROOTS_PARSE"
	exit 1
fi