kvm-mount

#!/bin/bash
#
# Mount a raw kvm image.  Assumes it's partitioned, and the partition to mount is the last one.

PARTCMD='tail -n1'

# Set usage output
USAGE="[-h |--help] [-f | --first-partition ] [<img-file>]"
LONGUSAGE="\t-h, --help\n\t\tPrint this help message
\t-f, --first-partition\n\t\tMount the first partition, rather than the last
\t<img-file>\n\t\tImage file to mount (defaults to IMGFILE from kvm-run.conf)"

# Standard functions
source ${HOME}/.scripts/functions.sh

# Script name
ME=$(basename $0)

# Parse arguments
ARGS=`getopt -o hf --long help,first-partition -n "${ME}" -- "$@"`

if [ $? != 0 ] ; then
	usage "invalid arguments"
fi
eval set -- "$ARGS"

while true ; do
	case "$1" in
		-h|--help) usage; shift ;;
		-f|--first-partition) FIRSTPART='yes'; shift ;;
		--) shift ; break ;;
		* ) usage "Invalid argument $1";;
	esac
done

# Remaining arguments are in $1, $2, etc. as normal

if [ -n "${1}" ]; then
	IMGFILE="${1}"
elif [ ! -f kvm-run.conf ]; then
	die "No img-file given, and no kvm-run.conf"
else
	source kvm-run.conf
	# Sets IMGFILE
fi

if [ -z "${IMGFILE}" ]; then
	die "IMGFILE empty!"
fi

if [ -z "$(file ${IMGFILE} | grep "x86 boot sector")" ]; then
	die "${IMGFILE} is not a raw image file"
fi

if [ -n "$FIRSTPART" ]; then
	PARTCMD='head -n1'
fi

STARTSECTOR=$(file ${IMGFILE} | grep -o "startsector [0-9]*" | ${PARTCMD} | awk '{print $2}')

ROOTOFFSET=$((${STARTSECTOR} * 512))

if [ ! -d mnt ]; then
	sudo mkdir mnt
fi

sudo mount -o loop,offset=${ROOTOFFSET} ${IMGFILE} mnt/

if [ ! -d mnt/boot ]; then
	die "No boot; not mounted"
fi

if [ -z "$FIRSTPART" ]; then
	STARTSECTOR=$(file ${IMGFILE} | grep -o "startsector [0-9]*" | head -n 1 | awk '{print $2}')
	BOOTOFFSET=$((${STARTSECTOR} * 512))
	sudo mount -o loop,offset=${BOOTOFFSET} ${IMGFILE} mnt/boot/
fi