#!/bin/sh
# pre install script for the Debian bind9 package

set -e

# Check if we are upgrading while running a kernel before 2.2.18. If so abort
# immediately since we don't support those kernels anymore.
if [ "$1" = "upgrade" ] && dpkg --compare-versions "`uname -r`" lt 2.2.18 ; then
        cat <<EOF
ERROR: you are running a pre-2.2.18 kernel on this machine. Recent
versions of bind9 no longer support those kernels.
To prevent breaking nameservices on this system bind9 upgrade will abort.
EOF
        exit 1
fi

APP_PROFILE="usr.sbin.named"
APP_CONFFILE="/etc/apparmor.d/$APP_PROFILE"
APP_COMPLAIN="/etc/apparmor.d/force-complain/$APP_PROFILE"
if [ "$1" = "upgrade" ]; then
    mkdir -p `dirname $APP_COMPLAIN` 2>/dev/null || true
    if dpkg --compare-versions $2 lt 1:9.3.4-2ubuntu2 ; then
        # force-complain for pre-apparmor upgrades
        ln -sf $APP_CONFFILE $APP_COMPLAIN
    elif dpkg --compare-versions $2 lt 1:9.4.2-3ubuntu1 ; then
        if [ -e "$APP_CONFFILE" ]; then
            md5sum="`md5sum \"$APP_CONFFILE\" | sed -e \"s/ .*//\"`"
            pkg_md5sum="`sed -n -e \"/^Conffiles:/,/^[^ ]/{\\\\' $APP_CONFFILE'{s/.* //;p}}\" /var/lib/dpkg/status`"
            if [ "$md5sum" = "$pkg_md5sum" ]; then
		# force-complain when upgrade from pre-shipped profile and an existing
                # profile is same as in conffiles
                ln -sf $APP_CONFFILE $APP_COMPLAIN
            fi
        else
            # force-complain on upgrade from pre-shipped profile and
            # there is no existing profile
            ln -sf $APP_CONFFILE $APP_COMPLAIN
        fi
    fi
fi


#DEBHELPER#
exit 0