#!/usr/bin/env bash
# vim: tabstop=4 shiftwidth=4 softtabstop=4

# Copyright 2010 United States Government as represented by the
# Administrator of the National Aeronautics and Space Administration.
# All Rights Reserved.
#
#    Licensed under the Apache License, Version 2.0 (the "License"); you may
#    not use this file except in compliance with the License. You may obtain
#    a copy of the License at
#
#         http://www.apache.org/licenses/LICENSE-2.0
#
#    Unless required by applicable law or agreed to in writing, software
#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
#    License for the specific language governing permissions and limitations
#    under the License.

INSTANCES_PATH=${INSTANCES_PATH:-/var/lib/nova/instances}
if [ -z "$1" ]; then echo "specify an instance id to debug"; exit; fi

if [ -n "$3" ]; then DEVICE=$3; fi

CMD="all"
if [ -n "$2" ]; then CMD=$2; fi

cd $INSTANCES_PATH/$1

if [ $CMD != "umount" ] && [ $CMD != "launch" ]; then
# destroy the instance
virsh destroy $1

# mount the filesystem
mkdir t
DEVICE=`losetup --show -f disk`
echo $DEVICE
kpartx -a $DEVICE
mount /dev/mapper/${DEVICE:4}p1 t

fi
if [ $CMD != "mount" ] &&  [ $CMD != "umount" ]; then

# make serial console listen on ttyS0
cat >t/etc/init/ttyS0.conf <<TTY_EOF
# ttyS0 - getty
#
# This service maintains a getty on ttyS0 from the point the system is
# started until it is shut down again.

start on stopped rc RUNLEVEL=[2345]
stop on runlevel [!2345]

respawn
exec /sbin/getty -L 115200 ttyS0 xterm
TTY_EOF

echo
# set debug root password
chroot t passwd -u root
# TODO(vish): automate this with expect
chroot t passwd root

tr -d '\n' < libvirt.xml > debug.xml
sed -i "s/<serial type=\"file\">.*<\/serial>/<serial type=\"pty\"><source path=\"\/dev\/pts\/1\"\/><target port=\"0\"\/><\/serial>/g" debug.xml

umount t

virsh create debug.xml
virsh console $1
virsh destroy $1

mount /dev/mapper/${DEVICE:4}p1 t

# clear debug root password
chroot t passwd -l root

# remove the serial console conf
rm -f t/etc/init/ttyS0.conf

fi
if [ $CMD != "mount" ] && [ $CMD != "launch" ]; then

# unmount the filesystem
umount t
kpartx -d $DEVICE
losetup -d $DEVICE
rmdir t

# recreate the instance
virsh create libvirt.xml
fi
