#!/bin/sh
#
# =head1 NAME
#
# mkcd - burn a data CD from an ISO image or data directory
#
# =head1 SYNOPSIS
#
# mkcd [-n] [dev=device] [speed=n] [blank=mode] {image.iso|dir}
#
# =head1 DESCRIPTION
#
# I<mkcd> is a script to burn data CD-Rs.
# It is partner to mkiso(1cs), a program to make ISO9660 CD images.
# Normally you would hand it a premade ISO9660 CD image to burn.
# Alternatively you can hand it a directory containing the data for the CD
# and it will call mkiso(1cs) to make the requisite CD image for you.
#
# =head1 OPTIONS
#
# =over 4
#
# =item B<-n>
#
# No action. Run cdrecord(1) in dummy mode.
#
# =item B<-l> I<label>
#
# If handing a directory to I<mkcd>
# this can be used to supply a I<label> string in lieu of a B<LABEL> file.
# 
# =back
#
# =head1 CDRECORD ARGUMENTS
#
# The following arguments are passed to cdrecord(1).
# The script obtains defaults for these from the configuration files
# and the B<MKCDDEV> environment variable.
#
# =over 4
#
# =item B<dev=I<bus>,I<id>,I<lun>>
#
# Specifiy the location of the CD burner on the SCSI bus.
# Recent cdrecord(1)s can also support IDE as B<dev=/dev/hd>I<x>.
#
# =item B<speed=I<n>>
#
# Specify the burn speed.
#
# =item B<blank=I<type>>
#
# Blank a CD-RW before writing.
#
# =back
#
# =head1 FILES
#
# /etc/mkcdrc, a shell script to set I<mkcd> defaults
# being B<speed=> and B<dev=>
#
# $HOME/.mkcdrc, personal I<mkcd> settings, also a shell script
#
# =head1 ENVIRONMENT
#
# MKCDDEV, the B<I<bus>,I<id>,I<lun>> string used in B<dev=I<bus>,I<id>,I<lun>>.
# For example I set this to B<0,4,0> on our work CD burning machine.
#
# =head1 SEE ALSO
#
# mkiso(1cs), mkisofs(1), cdrecord(1)
#
# =head1 CREDITS
#
# I<mkcd> is really just a wrapper for the cdrecord(1) command
# by Joerg Schilling.
#
# =head1 AUTHOR
#
# Cameron Simpson <cs@zip.com.au> 12jul2000
#

cdrecord=cdrecord
scsiid=4	# for my work CD burner, 6 is also common
speed="speed=12"
blank=
dummy=
dev=${MKCDDEV:+dev=$MKCDDEV}

# override scsiid or speed or blank here
[ -s /etc/mkcdrc ] && . /etc/mkcdrc
[ -f $HOME/.mkcdrc ] && . $HOME/.mkcdrc
[ -n "$dev" ] || dev="dev=0,$scsiid,0"

cmd=`basename "$0"`
usage="Usage: $cmd [-n] [-l label] [dev=device] [speed=n] [blank=mode] image.iso
	-l label	Label string (only useful if \"image.iso\" is
			a directory instead of an ISO9660 image.
			(VOLI field, up to 32 bytes).
	-n		No action (cdrecord's -dummy flag).
	cdrecord=cmd	Use cmd as the cdrecord invocation.
			Default: $cdrecord
	dev=device	Passed to cdrecord.
			Default: $dev
	speed=n		Passed to cdrecord.
	blank=mode	Passed to cdrecord."

badopts=
label=
while :
do  case $1 in
      -l)	label=$2; shift ;;
      -n)	dummy=-dummy ;;
      dev=?*)	dev=$1 ;;
      speed=?*)	speed=$1 ;;
      blank=?*)	blank=$1 ;;
      cdrecord=?*) cdrecord=`expr "x$1" : 'xcdrecord=\(.*\)'` ;;
      --)	shift; break ;;
      -?*)	echo "$cmd: unrecognised option: $1" >&2
		badopts=1
		;;
      *)	break ;;
    esac
    shift
done

if [ $# = 0 ]
then
    echo "$cmd: missing image.iso" >&2
    badopts=1
else
    iso=$1; shift
    [ $# = 0 ] || { echo "$cmd: extra arguments: $*" >&2
		    badopts=1
		  }
fi

[ $badopts ] && { echo "$usage" >&2; exit 2; }

ok=1

if [ -d "$iso/." ]
then
    tmpiso=mkcd$$.iso
    mkiso -l "$label" -o "$tmpiso" "$iso" \
	|| { echo "$cmd: mkiso fails" >&2; rm -f "$tmpiso"; exit 1; }
    iso=$tmpiso
else
    tmpiso=
fi

[ -s "$iso" ] || { echo "$cmd: need nonempty file: $iso" >&2; ok=; }

if [ $ok ]
then
    set -x
    $cdrecord -v $dummy -eject $speed $blank "$dev" -data "$iso"
    xit=$?
    set +x
else
    xit=1
fi

[ -n "$tmpiso" ] && rm -f "$tmpiso"

exit $xit