OpenNebula

#! /usr/bin/env bash

set -e

output="$1"

size="$2"

if [ -z "${output}" -o -z "${size}" ]; then

	echo "Usage: mkswap-qemu <output> <sizeInMB> <mkswapArgs>..." >&2

	exit 1

fi

if [ $[${size} / 1] != "${size}" ] 2>/dev/null; then

	echo "Invalid size specified: ${size}" >&2

	exit 1

fi

shift; shift

mkswap_args=("$@")

tmpfile1=''

tmpfile2=''

function cleanup() {

	rm -f "${tmpfile1}" "${tmpfile2}"

}

trap cleanup EXIT

tmpfile1="$(mktemp)"

tmpfile2="$(mktemp)"

pagesize="$(getconf PAGESIZE)"

dd if=/dev/zero of="${tmpfile1}" bs=$[1024*1024] seek=$[${size} - 1] count=1 2>/dev/null

mkswap "${mkswap_args[@]}" "${tmpfile1}"

dd if="${tmpfile1}" bs="${pagesize}" count=1 of="${tmpfile2}" 2>/dev/null

case "${output}" in

	rbd:*)

		output_format='raw'

		;;

	*.qcow2)

		output_format='qcow2'

		;;

	*)

		# Default: raw

		output_format='raw'

		;;

esac

qemu-img convert -O "${output_format}" -f raw "${tmpfile2}" "${output}"

qemu-img resize -f "${output_format}" "${output}" "${size}M"

exit 0