From a356b2d303137a9c05ece0197dcff925ffc4244f Mon Sep 17 00:00:00 2001
From: Mike Frysinger <vapier@gentoo.org>
Date: Thu, 2 Jan 2014 15:34:02 -0500
Subject: [PATCH] backup-dvd: handle errors

---
 .bin/backup-dvd | 38 ++++++++++++++++++++++++++++++++------
 1 file changed, 32 insertions(+), 6 deletions(-)

diff --git a/.bin/backup-dvd b/.bin/backup-dvd
index a4dfdab..ef79dde 100755
--- a/.bin/backup-dvd
+++ b/.bin/backup-dvd
@@ -11,6 +11,7 @@ usage() {
 	 -n <volume name>    Defaults to volume on disk
 
 	Commands:
+	 --errors   Image the raw disc first w/ddrescue
 	 --backup   Back up the disc
 	 --modify   Tweak runtime settings (needs -n)
 	 --mkiso    Create an iso (needs -n)
@@ -25,8 +26,9 @@ out=${PWD}
 vol=
 
 unset doit_{backup,modify,mkiso}
+doit_errors=false
 
-eval set -- `getopt -l backup,modify,mkiso -- hi:n:o: "$@"`
+eval set -- `getopt -l errors,backup,modify,mkiso -- hi:n:o: "$@"`
 while [[ -n $1 ]] ; do
 	case $1 in
 		-h) usage;;
@@ -34,6 +36,7 @@ while [[ -n $1 ]] ; do
 		-o) out=$2; shift 2;;
 		-n) vol=$2; shift 2;;
 
+		--errors) doit_errors=true; shift;;
 		--backup) doit_backup=true; shift;;
 		--modify) doit_modify=true; shift;;
 		--mkiso)  doit_mkiso=true;  shift;;
@@ -98,16 +101,32 @@ e() {
 	"$@"
 }
 
+#
+# Mirror the disc w/ddrescue which tolerates errors.
+#
+raw_read_dvd() {
+	echo "Imaging disc"
+	local raw=".${Volume}.raw"
+	local log="${raw}.log"
+	local opts=(
+		-v -b 2048 ${dev} "${raw}" "${log}"
+	)
+	ddrescue -p -n "${opts[@]}"
+	ddrescue -d -r 3 "${opts[@]}"
+	ddrescue -d -r 3 -R "${opts[@]}"
+	dev=${raw}
+}
+
 #
 # Backup the disc.
 #
-opts=(
-	-i ${dev}
-	-o "${out}"
-	-n "${Volume}"
-)
 backup_dvd() {
 	echo "Backing up: ${Volume}"
+	local opts=(
+		-i ${dev}
+		-o "${out}"
+		-n "${Volume}"
+	)
 	if ! e dvdbackup -M "${opts[@]}" ; then
 		e dvdbackup -F "${opts[@]}" || exit 1
 	fi
@@ -298,6 +317,11 @@ modify_dvd() {
 	local out_vts_dir="${out}/${Volume}/VIDEO_TS"
 	local vmgi vtsi
 
+	if ${doit_errors} ; then
+		echo "skipping modifications due to possible errors in files"
+		return
+	fi
+
 	for vmgi in "${out_vts_dir}"/VIDEO_TS.{IFO,BUP} ; do
 		process_vmgi "${vmgi}"
 		check_changes "${vmgi}" || exit 1
@@ -335,8 +359,10 @@ mkiso_dvd() {
 	"${sh}" || exit
 
 	du -h "${out}/${Volume}.iso"
+	sudo chattr +i "${out}/${Volume}.iso"
 }
 
+${doit_errors} && raw_read_dvd
 ${doit_backup} && backup_dvd
 ${doit_modify} && modify_dvd
 ${doit_mkiso} && mkiso_dvd
-- 
2.39.5