#!/bin/bash
#
# Copyright 2012 Hewlett-Packard Development Company, L.P.
# 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.

set -e

SCRIPTNAME=$(basename $0)
export _LIB=$(dirname $0)/../lib
source $_LIB/die

function show_options () {
    echo "Usage: $SCRIPTNAME -i <image> [-d <outdir>] [-o <prefix]"
    echo
    echo "Options:"
    echo "    -i filename -- extract kernel + ramdisk from this file"
    echo "    -d dir      -- save files in \$dir; defaults to /tmp"
    echo "    -o prefix   -- set the prefix of the output files; defaults to 'baremetal'"
    echo "                   eg, baremetal-vmlinuz and baremetal-initrd"
    echo "    -x          -- turn on tracing"
    echo "    -h          -- print this message"
    exit 0
}

TEMP=`getopt -o hd:i:o:x -n $SCRIPTNAME -- "$@"`
echo "XXX $TEMP"
if [ $? != 0 ] ; then echo "Terminating..." >&2 ; exit 1 ; fi

# Note the quotes around `$TEMP': they are essential!
eval set -- "$TEMP"

export OUT_DIR=/tmp
export OUT_PFX=baremetal

while true ; do
    case "$1" in
        -d) export OUT_DIR=$2; shift 2 ;;
        -i) export IMAGE_FILE=$2; shift 2 ;;
        -o) export OUT_PFX=$2; shift 2 ;;
        -h) show_options;;
        -x) shift; set -x;;
        --) shift ; break ;;
        *) echo "Internal error!" ; exit 1 ;;
    esac
done

if [[ ! -n "$IMAGE_FILE" ]]; then
   die "You must specify an image to read from with -i \$filename"
elif [[ ! -r "$IMAGE_FILE" ]]; then
   die "Image file $IMAGE_FILE is not readable"
fi

source $_LIB/img-defaults
source $_LIB/common-functions
source $_LIB/img-functions

echo "Extracting kernel + ramdisk from $IMAGE_FILE and writing them to $OUT_DIR"

ensure_nbd

# sets WORK_DIR
mount_qcow_image $IMAGE_FILE

# Dig up the initrd and kernel to use.
BOOTDIR="$WORK_DIR/boot"
KERNEL=$(basename `ls -1 $BOOTDIR/vmlinuz*generic | sort -n | tail -1`)
RAMDISK=$(basename `ls -1 $BOOTDIR/initrd*generic | sort -n | tail -1`)
sudo cp $BOOTDIR/$KERNEL $OUT_DIR/$OUT_PFX-vmlinuz
sudo cp $BOOTDIR/$RAMDISK $OUT_DIR/$OUT_PFX-initrd
sudo chmod a+r $OUT_DIR/$OUT_PFX-vmlinuz
sudo chmod a+r $OUT_DIR/$OUT_PFX-initrd

unmount_qcow_image

echo "$OUT_PFX-vmlinuz,$OUT_PFX-initrd"