vdimount.sh

#!/bin/sh

TEMP_OUTPUT_FILENAME="vdistart"

# command paths
SFDISK=`which sfdisk`
DD=`which dd`
OD=`which od`
AWK=`which awk`
GREP=`which grep`
RM=`which rm`
MOUNT=`which mount`

if [ `id -u` != "0" ]; then
	echo "This script must be run as root." 1>&2
	exit 1
fi

if [ -z $1 ]; then
	echo "Image file argument is missing." 1>&2
	exit 1
fi

if [ -z $2 ]; then
	echo "Mount point argument is missing." 1>&2
	exit 1
fi

if [ ! -e $1 ]; then
	echo "Passed image file does not exist." 1>&2
	exit 1
fi

if [ ! -d $2 ]; then
	echo "Mount point does not exist." 1>&2
	exit 1
fi

# Check if chosen image file is fixed-size
if [ `$OD -j76 -N4 -td4 $1 | $AWK 'NR==1{print $2}'` = "2" ]; then
	# determine offset to beginning of filesystem
	DATA_OFFSET=`$OD -j344 -N4 -td4 $1 | $AWK 'NR==1{print $2}'`

	# determine offset to beginning of partition
	$DD if=$1 of=$TEMP_OUTPUT_FILENAME bs=1 skip=$DATA_OFFSET count=1b 2> /dev/null
	BLOCK_OFFSET=`$SFDISK -luS $TEMP_OUTPUT_FILENAME 2>/dev/null | $GREP "^$TEMP_OUTPUT_FILENAME" | $AWK 'NR==1{print $2}'`
	$RM $TEMP_OUTPUT_FILENAME

	# mount the image
	BLOCK_OFFSET=$(($BLOCK_OFFSET*512))
	$MOUNT -o loop,offset=$(($DATA_OFFSET+$BLOCK_OFFSET)) $1 $2 2>/dev/null

	if [ $? = "0" ]; then
		echo "Mounted image file successfully."
		exit 0
	else
		echo "Failed to mount image file. (Is the file already mounted?)"
		exit 1
	fi
else
	echo "Image file must be fixed size.\n" 1>&2
	echo "You can clone it to a raw image by using the following command:"
	echo 
	echo "    VBoxManage clonehd --format RAW <filename>.vdi <filename>.img"
	echo 
	echo "and mount it afterwards:"
	echo 
	echo "    mount -t ext3 -o loop,rw ./ubuntu.img /mnt"
	echo 
	echo "sorry... :("
	exit 1
fi