#!/bin/sh
me="`basename $0`"
usage(){
cat <<EOF
$me - make a disk image from files and/or directories
usage:
  $ $me pathto/volname file|directory [..]
	- generate pathto/volname.dmg contains specified files and directories
author(s):
  Taiji Yamada <taiji@aihara.co.jp>
EOF
  exit 1
}
[ "$1" = "" ] && usage
pathname="$1"; shift
[ $# = 0 ] && usage

echo_eval(){
  echo "$@"
  eval "$@"
}

sectors(){
  du "$1" | tail -n 1 | cut -f 1
}
totalsectors(){
  t=0
  for a in "$@"; do
    s="`sectors \"$a\"`"
    t=`expr "$t" + "$s"`
  done
  echo $t
}
diskimagesectors(){
  s=`totalsectors "$@"`
  s=`expr $s \* 110 / 100`
  [ $s -lt 1024 ] && echo 1024 || echo $s
}

volname="`basename \"$pathname\"`"
z=`diskimagesectors "$@"`
dmg="$pathname.dmg"
tmp_dmg="$pathname.tmp.dmg"
mnt="/tmp"
volpath="$mnt/$volname"
#fmt=UDRO
#fmt=UDZO
fmt=UDBZ
#fmt=UDRW

echo_eval hdiutil create -sectors ${z} "'$tmp_dmg'" -type UDIF -fs HFS+ -volname "'$volname'" -layout NONE -quiet	&&
echo_eval hdiutil attach "'$tmp_dmg'" -mountroot "'$mnt'" -quiet	&& {
echo "tar cf - \"$@\" | ( cd \"$volpath\" && tar xf - )"	&&
tar cf - "$@" | ( cd "$volpath" && tar xf - )
}	&&
echo_eval hdiutil detach "'$volpath'" -quiet	&&
echo_eval hdiutil convert "'$tmp_dmg'" -format $fmt -o "'$dmg'" -quiet	&&
echo_eval rm -f "'$tmp_dmg'"	&&
echo "$dmg"	&&
exit 0	||
{
  echo_eval hdiutil detach "'$volpath'" -quiet	&&
  echo_eval rm -f "'$tmp_dmg'"	|| true
  echo $0: error at making "$dmg"
  [ -d "$volpath" ]	&& echo hdiutil detach "$volpath" -quiet
  [ -f "$tmp_dmg" ]	&& echo rm -f "$tmp_dmg"
  [ -f "$dmg" ]		&& echo rm -f "$dmg"
  exit 1
}