#!/bin/bash

set -x

# If this script is not run as root, the DMG will have incorrect ownership

if [ $EUID -ne 0 ] ; then

# If this is being invoked with the intention of being privileged,

# this failure is a hard error.

if [ "${GENERATE_DMG_SCRIPT}" != "" ] ; then

echo >&2 "ERROR: this script must be run as root"

exit -1

fi

echo >&2 "WARNING: not building DMG as root; app will have incorrect ownership"

fi

# Arguments are the name of the volume to create, the input folder and the output filename

if [ $# -ne 3 ] ; then

echo >&2 "ERROR: usage: ./generate-dmg.sh volname srcfolder output"

exit -2

fi

volname="$1"

srcfolder="$2"

output="$3"

# Make the DMG

# UID and GID 99 are magical - they are needed to ensure ownership is correct

# when the app bundle is copied out of the DMG. They are also the reason that

# this script needs to be run with root permissions.

#

if [ $EUID -eq 0 ] ; then

ids="-uid 99 -gid 99"

fi

hdiutil create -fs HFS+ -format UDRW -scrub ${ids} -attach -volname "${volname}" -srcfolder "${srcfolder}" "${output}"

# Ensure the ownership of the output image is correct

user=$(who am i | awk '{print $1}')

group=$(id -g -n "${user}")

chown ${user}:${group} "${output}"

chmod 644 "${output}"