#!/bin/bash -
# virt-bmap
# Copyright (C) 2014 Red Hat Inc.
#
# 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 of the License, 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.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.

# 'virt-bmap' is a shell script wrapper that runs nbdkit with the
# right options.  Read virt-bmap(1) before trying to use this program.
#
# If you want to run this without installing then use the './run'
# script in the build directory, eg:
#
#   ./run virt-bmap -o bmap disk.img

program=virt-bmap
version="@PACKAGE_VERSION@"

output=bmap
format=raw

TEMP=`getopt \
        -o f:o:V \
        --long help,format:,output:,version \
        -n $program -- "$@"`
if [ $? != 0 ]; then
    echo "$program: problem parsing the command line arguments"
    exit 1
fi
eval set -- "$TEMP"

usage ()
{
    echo "Usage:"
    echo "  $program [-o bmap] [--format raw|qcow2|...] disk.img"
    echo
    echo "Read $program(1) man page for more information."
    exit $1
}

while true; do
    case "$1" in
        -f|--format)
            format="$2"
            shift 2;;
        -o|--output)
            output="$2"
            shift 2;;
        -V|--version)
            echo "$program $version"
            exit 0;;
        --help)
            usage 0;;
        --)
            shift
            break;;
        *)
            echo "internal error ($1)"
            exit 1;;
    esac
done

# At the moment we only support a single disk image argument.
# Supporting multiple disk images requires adding support for export
# names to nbdkit.
if [ $# -ne 1 ]; then
    echo "$program: Missing disk image argument.  See $program(1)."
    exit 1
fi

# Turn the disk image arguments into disk=...
declare -a disks
for arg in "$@"; do
    disks+=("disk=$arg")
done

# Deal with stupid autotools libdir-not-expandable crap.
prefix="@prefix@"
exec_prefix="@exec_prefix@"
libdir="@libdir@"

# Get the examiner plugin.
if [ -z "$VIRTBMAP_PLUGIN_DIR" ]; then
    VIRTBMAP_PLUGIN_DIR="$libdir"
fi

# Create the socket.
tmpdir="$(mktemp -d)"
cleanup ()
{
    rm -rf "$tmpdir" ||:
}
trap cleanup EXIT ERR
socket="$tmpdir/socket"

# Run nbdkit with plugin and arguments.
nbdkit -r -f -U "$socket" \
       "$VIRTBMAP_PLUGIN_DIR/virtbmapexaminer.so" \
       output="$output" \
       format="$format" \
       socket="$socket" \
       "${disks[@]}"