isosuck

#!/bin/sh

version="1.1.0.20210912"

help() { cat <</help
Usage: isosuck [DVD Title] [DVD DEVICE]

DVD Title will default to the volume ID of the DVD
Output will be <DVD Title>.iso
DVD DEVICE will default to /dev/dvd

isosuck $version Copyright 2010+ by Adam Katz, GPLv2
Learn more at https://github.com/adamhotep/media-scripts
/help
  exit
}

version() { cat <</version
isosuck $version
Copyright (C) 2010+  Adam Katz
License GPLv2+: GNU GPL version 2 or later <https://gnu.org/licenses/gpl.html>.
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.
/version
  exit
}

license() { cat <</license
Copyright (C) 2010+  Adam Katz

This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 2 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program.  If not, see <http://www.gnu.org/licenses/>.
/license
  exit
}

# silently returns true only when we have all of the given command(s)
we_have() { command -v "$@" >/dev/null 2>&1; }

# print the arguments and exit the entire program
die() { echo "$*" >&2; exit 2; }

while getopts hLV-: OPT; do
  case "$OPT" in
    (h) help ;;
    (L) license ;;
    (V) version ;;
    (-) case "$OPTARG" in
          (help)	help ;;
          (license)	license ;;
          (version)	version ;;
          (*)		die "Illegal option --$OPTARG ... Try --help" ;;
        esac ;;
    (\?) die "Try --help" ;;
  esac
done
shift $((OPTIND-1))

if ! we_have isoinfo; then
  echo "This program requires isoinfo; try installing genisoimage or cdrkit" >&2
  exit 2
fi

# Get title from command line argument, strip trailing `.iso` (we add it later)
title="${1%.iso}"

for device in "$2" "/dev/dvd" "/dev/sr0" "/dev/sr1" "/dev/sr2" "/dev/sr3"; do
  if [ -b "$device" ]; then
    break
  fi
done

if [ ! -b "$device" ]; then
  echo "ERROR: Could not find an appropriate DVD device." >&2
  exit 2
elif [ -n "$2" ] && [ "$2" != "$device" ]; then
  echo "WARNING: '$2' is not a block device, using '$device' instead." >&2
  sleep 1
fi

dvdinfo() { isoinfo -d -i "$device" 2>/dev/null; }

if we_have dc3dd; then
  image() { dc3dd hash=md5 if="$device" of="$1"; }
else
  if we_have md5sum; then # GNU
    hash() { md5sum "$1" |awk '{print $1}'; }
  elif we_have md5; then # BSD
    hash() { md5 "$1" |awk '{print $NF}'; }
  elif we_have cksum; then # old POSIX (use sum and size)
    hash() { cksum "$1" |awk '{print $1,$2}'; }
  else  # wtf, no cksum?!  use just size
    hash() { /bin/ls -l "$1" |awk '{print $5}'; }
  fi
  image() {
    local retval orig new
    dd if="$device" of="$1"
    retval=$?
    if [ $retval != 0 ]; then
      echo "WARNING: dd did not exit cleanly (code $retval)" >&2
      echo "         (performing hash check anyway, may be a waste of time)" >&2
    fi
    orig="$(hash "$device")"
    new="$(hash "$1")"
    if [ "$orig" != "$new" ]; then
      echo "FAILURE: Hash mismatch on output '$1'" >&2
      return 1
    else
      echo "Success: Hash matches original source."
    fi
    return $retval
  }
fi

default_title=DVD_VIDEO

if [ -z "$title" ]; then
  title="$(dvdinfo |sed '/^Volume id: /!d; s///')"
fi
if [ -z "$title" ]; then
  title="DVD_VIDEO"
fi
if [ "$title" = "$default_title" ]; then
  i=1
  base="$default_title"
  while [ -s "$title.iso" ]; do
    title="$base-$i"
    i=$((i+1))
  done
fi

if [ -s "$title.iso" ]; then
  echo "Output '$title.iso' already exists, aborting." >&2
  exit 1
fi

# not posix but present nearly everwhere (GNU coreutils, BSD). Fallback:
if ! we_have readlink; then
  # Usage: readlink [-f] LINK
  # Print the target of given LINK, keep following given -f, limit=100 (~0.33s)
  readlink() {
    local canonicalize= file="$1" target= i=0
    case "$1" in ( -f | --canonicalize ) canonicalize=1 file="$2" ;; esac
    if [ -n "${file##/*}" ]; then file="$PWD/$file"; fi
    while [ -L "$file" ] && [ $i -le 100 ]; do
      target="$(ls -dl "$file")" || break
      target="${target#* $file -> }"
      if [ -n "${target##/*}" ]; then target="${file%/*}/$target"; fi
      if [ -e "$target" ]; then file="$target"; else break; fi
      if [ -z "$canonicalize" ]; then break; fi
      i=$((i+1))
    done
    echo "$file"
  }
fi

true_device="$(readlink -f "$device" 2>/dev/null || echo "$device")"
mounted="$(mount |awk -v dvd="$true_device" '$1 == dvd')"
mounted="${mounted#* on /}"
mounted="${mounted% type *}"
oldtitle="${mounted##*/}"
if [ -n "$mounted" ] && [ "$mounted" = "${mounted%*/$title}" ]; then
  mounted="/$mounted"
  echo "WARNING: You appear to have a different DVD ($oldtitle) mounted."
  echo "         This could result in the output being truncated."
  echo "         I'll UNMOUNT '$mounted' in five seconds.  You've been warned."
  sleep 5
  umount "$mounted" || sudo umount -v "$mounted"
fi

location="$(dirname "$title.iso")"
free="$(df -k "$location" |awk 'NR==2 && $4 { print $4 }')"

size="$(dvdinfo |awk '
  /^Logical block size is:/ { block = $NF }
  /^Volume size is:/ { vol = $NF }
  END {
    size = sprintf("%.0f", block * vol / 1024)
    min = 4 * 1024^2   # a minimum size in case isoinfo fails
    printf "%.0f", (size > min ? size : min)
  }
')"

awk -v title="$title" -v size="$size" -v device="$device" 'BEGIN {
  printf "Will write `%s.iso` (%.2fG) from `%s`", title, size / 1024^2, device
}'
sleep 2

# warn if we'd have less than 1GB free after ripping
if [ $size -ge $((free-1024*1024)) ]; then
  awk -v size="$size" -v free="$free" 'BEGIN {
    printf "WARNING: Disk image is %.2fG but we only have %.2fG free space\n",
      size / 1024^2, free / 1024^2
  }' >&2
  echo "... waiting 20 seconds for you to cancel"
  sleep 20
  echo
fi

if [ "${TERM:-no_term}" = "${TERM#[Ll]inux}" ]; then
  printf "\033]0;${0##*/}: $title\a"
fi

image "$title.iso"
retval=$?

actual_size="$(du -k "$title.iso" |awk '{print $1}')"

# if actual size is 5+ MB smaller than expected size
if [ "$actual_size" -lt "$((size-5*1024))" ]; then
  echo "$actual_size $size" |awk '{
    printf "WARNING: final size (%.2fG) is %.1fM smaller than expected (%.2fG)",
      $1 / 1024 / 1024, ($2 - $1) / 1024, $2 / 1024 / 1024;
  }' >&2
  exit 2
fi

exit $retval