#!/bin/bash
#
# Copyright 2012 Hewlett-Packard Development Company, L.P.
#
# 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 $0)
SCRIPT_HOME=$(dirname $0)
if [ -d $SCRIPT_HOME/../share/diskimage-builder ]
then
    export _PREFIX=$SCRIPT_HOME/../share/diskimage-builder
else
    export _PREFIX=$SCRIPT_HOME/..
fi
export _LIB=$_PREFIX/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
}

echo 'DEPRECATED: Please consider using the `baremetal` element.'
echo

TEMP=`getopt -o hd:i:o:x -n $SCRIPTNAME -- "$@"`
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 to $OUT_PFX-vmlinuz and $OUT_PFX-initrd in $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=
RAMDISK=
if [ -f $WORK_DIR/etc/redhat-release ]; then

    # Prioritize PAE if present
    KERNEL=$(ls -1rv $BOOTDIR/vmlinuz*  | grep PAE | grep -v debug | head -1)
    if [ ! $KERNEL ]; then
        KERNEL=$(ls -1rv $BOOTDIR/vmlinuz* | grep -v debug | head -1)
        if [ ! $KERNEL ]; then
            echo "No suitable kernel found."
            exit 1
        fi
    fi

    KERNEL=$(basename $KERNEL)
    KERNEL_VERSION=`echo $KERNEL | sed 's/vmlinuz-//g'`

    RAMDISK=$(basename `ls $BOOTDIR/initramfs-$KERNEL_VERSION.img`)
    if [ ! $RAMDISK ]; then
        echo "Can't find an initramfs for the $KERNEL_VERSION version of the kernel."
        exit 1
    fi

elif [ -f $WORK_DIR/etc/debian_version ]; then
    KERNEL=$(basename `ls -1rv $BOOTDIR/vmlinuz*generic | head -1`)
    RAMDISK=$(basename `ls -1rv $BOOTDIR/initrd*generic | head -1`)
elif [ -f $WORK_DIR/etc/SuSE-release ]; then
    KERNEL=$(basename `ls -1rv $BOOTDIR/vmlinuz`)
    RAMDISK=$(basename `ls -1rv $BOOTDIR/initrd`)
else
    echo "ERROR: Unable to detect operating system"
    exit 1
fi

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