path: root/policy-rc.d

#!/bin/sh

# $Id: policy-rc.d,v 1.4 2007-01-03 14:38:03 jonas Exp $
#
# Copyright © 2006 Jonas Smedegaard <dr@jones.dk>
# Description: Suppress system V scripts if invoked within a chroot.
#
# 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.

# Policy-rc.d is mentioned in manpage invoke-rc.d(8) and documented at
# http://people.debian.org/~hmh/invokerc.d-policyrc.d-specification.txt

set -e

PRG=`basename $0`

TEMP=`getopt -s sh --long list,quiet -n "$PRG" -- "$@"`
if [ $? != 0 ] ; then echo "Terminating..." >&2 ; exit 1 ; fi
eval set -- "$TEMP"

# Stolen from udev postinst
chrooted() {
    if [ "$(stat -c %d/%i /)" = "$(stat -Lc %d/%i /proc/1/root 2>/dev/null)" ];
    then
        # the devicenumber/inode pair of / is the same as that of /sbin/init's
        # root, so we're *not* in a chroot and hence return false.
        return 1
    fi
    echo "A chroot environment has been detected, udev not started."
    return 0
}

quiet=""
list=""
while true ; do
    case "$1" in
        --quiet) quiet="1" ; shift ;;
        --list) list="1" ; shift ;;
        --) shift ; break ;;
        *) echo "Internal error!" ; exit 1 ;;
    esac
done
initscript="$1"
actions="$2"
runlevel="$3"

if [ "$list" ]; then
    cat <<EOF
The following policies are known to this policy daemon:

    default:    All actions are allowed.
    chroot:     If invoked from within a chroot environment,
                no actions are allowed, else all are allowed.

This policy daemon care not about actions, so all standard actions
(start, [force-]stop, restart, [force-]reload and status), and any
additionally implemented ones, are supported.
EOF
    exit 0
fi

if ! chrooted; then
    if ! [ "$quiet" ]; then
        echo >&2 "Chroot environment detected, suppressing sysV script."
    fi
    exit 101
fi

exit 0