etc-update: rewrite significantly

This tool is very inefficient, especially in the case of auto-merging
with -3/-5 and such.  Rewrite the code to kill off dead paths, compress
multiple greps into a single sed, cache more calculated results, and
use bash code where possible rather than execing external tools.  There
are also style updates here, many of which fix quoting issues and other
such things.

The next rewrite should probably be in python, but this version is
fast enough for me now even on my slow machines.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>

1 files changed, 338 insertions, 305 deletions

diff --git a/bin/etc-update b/bin/etc-update
index 731b6484e..405822943 100755
--- a/bin/etc-update
+++ b/bin/etc-update
@@ -1,8 +1,9 @@
 #!/bin/bash
-# Copyright 1999-2011 Gentoo Foundation
+# Copyright 1999-2012 Gentoo Foundation
 # Distributed under the terms of the GNU General Public License v2
 
 # Author Brandon Low <lostlogic@gentoo.org>
+# Mike Frysinger <vapier@gentoo.org>
 #
 # Previous version (from which I've borrowed a few bits) by:
 # Jochem Kossen <j.kossen@home.nl>
@@ -11,9 +12,7 @@
 
 cd /
 
-if type -P gsed >/dev/null ; then
-	sed() { gsed "$@"; }
-fi
+type -P gsed >/dev/null && sed() { gsed "$@"; }
 
 get_config() {
 	# the sed here does:
@@ -25,10 +24,10 @@ get_config() {
 	# If there's more than one of the same configuration item, then
 	# the store to the hold space clobbers previous value so the last
 	# setting takes precedence.
-	local item=$1
-	eval echo $(sed -n \
+	local match=$1
+	eval $(sed -n -r \
 		-e 's:[[:space:]]*#.*$::' \
-		-e "/^[[:space:]]*$item[[:space:]]*=/{s:[^=]*=[[:space:]]*\([\"']\{0,1\}\)\(.*\)\1:\2:;h}" \
+		-e "/^[[:space:]]*${match}[[:space:]]*=/{s:^([^=]*)=[[:space:]]*([\"']{0,1})(.*)\2:\1=\2\3\2:;H}" \
 		-e '${g;p}' \
 		"${PORTAGE_CONFIGROOT}"etc/etc-update.conf)
 }
@@ -46,39 +45,49 @@ diff_command() {
 
 scan() {
 	echo "Scanning Configuration files..."
-	rm -rf ${TMP}/files > /dev/null 2>&1
-	mkdir ${TMP}/files || die "Failed mkdir command!" 1
+	rm -rf "${TMP}"/files > /dev/null 2>&1
+	mkdir "${TMP}"/files || die "Failed mkdir command!"
 	count=0
 	input=0
 	local find_opts
-	local my_basename
+	local path
 
 	for path in ${CONFIG_PROTECT} ; do
-		path="${EROOT}${path}"
+		path="${EROOT%/}${path}"
+
+		[[ -w ${path} ]] || die "Need write access to ${path}"
+
 		# Do not traverse hidden directories such as .svn or .git.
-		find_opts="-name .* -type d -prune -o -name ._cfg????_*"
-		if [ ! -d "${path}" ]; then
-			[ ! -f "${path}" ] && continue
-			my_basename="${path##*/}"
+		find_opts=( -name '.*' -type d -prune -o -name '._cfg????_*' )
+		if [[ ! -d ${path} ]] ; then
+			[[ ! -f ${path} ]] && continue
+			local my_basename="${path##*/}"
 			path="${path%/*}"
-			find_opts="-maxdepth 1 -name ._cfg????_${my_basename}"
+			find_opts+=( -maxdepth 1 -name "._cfg????_${my_basename}" )
 		fi
-
-		ofile=""
-		# The below set -f turns off file name globbing in the ${find_opts} expansion.
-		for file in $(set -f ; find ${path}/ ${find_opts} \
-		       ! -name '.*~' ! -iname '.*.bak' -print |
-			   sed -e "s:\(^.*/\)\(\._cfg[0-9]*_\)\(.*$\):\1\2\3\%\1%\2\%\3:" |
-			   sort -t'%' -k2,2 -k4,4 -k3,3 | LANG=POSIX LC_ALL=POSIX cut -f1 -d'%'); do
-
-			rpath=$(echo "${file/\/\///}" | sed -e "s:/[^/]*$::")
-			rfile=$(echo "${file/\/\///}" | sed -e "s:^.*/::")
+		find_opts+=( ! -name '.*~' ! -iname '.*.bak' -print )
+
+		local file ofile b=$'\001'
+		for file in $(find "${path}"/ "${find_opts[@]}" |
+		              sed \
+						-e 's://*:/:g' \
+						-e "s:\(^.*/\)\(\._cfg[0-9]*_\)\(.*$\):\1\2\3$b\1$b\2$b\3:" |
+		              sort -t"$b" -k2,2 -k4,4 -k3,3 |
+		              LC_ALL=C cut -f1 -d"$b")
+		do
+			local rpath rfile cfg_file live_file
+			rpath=${file%/*}
+			rfile=${file##*/}
+			cfg_file="${rpath}/${rfile}"
+			live_file="${rpath}/${rfile:10}"
+
+			local mpath
 			for mpath in ${CONFIG_PROTECT_MASK}; do
-				mpath="${EROOT}${mpath}"
-				mpath=$(echo "${mpath/\/\///}")
-				if [[ "${rpath}" == "${mpath}"* ]]; then
-					mv ${rpath}/${rfile} ${rpath}/${rfile:10}
-					break
+				mpath="${EROOT%/}${mpath}"
+				if [[ "${rpath}" == "${mpath}"* ]] ; then
+					echo "Updating masked file: ${live_file}"
+					mv "${cfg_file}" "${live_file}"
+					continue 2
 				fi
 			done
 			if [[ ! -f ${file} ]] ; then
@@ -87,39 +96,53 @@ scan() {
 			fi
 
 			if [[ "${ofile:10}" != "${rfile:10}" ]] ||
-			   [[ ${opath} != ${rpath} ]]; then
+			   [[ ${opath} != ${rpath} ]]
+			then
 				MATCHES=0
-				if [[ "${EU_AUTOMERGE}" == "yes" ]]; then
-					if [ ! -e "${rpath}/${rfile}" ] || [ ! -e "${rpath}/${rfile:10}" ]; then
+				if [[ ${eu_automerge} == "yes" ]] ; then
+					if [[ ! -e ${cfg_file} || ! -e ${live_file} ]] ; then
 						MATCHES=0
 					else
-						diff -Bbua ${rpath}/${rfile} ${rpath}/${rfile:10} | egrep '^[+-]' | egrep -v '^[+-][\t ]*#|^--- |^\+\+\+ ' | egrep -qv '^[-+][\t ]*$'
+						diff -Bbua "${cfg_file}" "${live_file}" | \
+							sed -n -r \
+								-e '/^[+-]/{/^([+-][\t ]*(#|$)|-{3} |\+{3} )/d;q0}' \
+								-e '$q1'
 						MATCHES=$?
 					fi
-				elif [[ -z $(diff -Nua ${rpath}/${rfile} ${rpath}/${rfile:10}|
-							  grep "^[+-][^+-]"|grep -v '# .Header:.*') ]]; then
+
+				elif diff -Nua "${cfg_file}" "${live_file}" |
+					sed -n \
+						-e '/# .Header:/d' \
+						-e '/^[+-][^+-]/q1' \
+						-e '$q0'
+				then
 					MATCHES=1
 				fi
-				if [[ "${MATCHES}" == "1" ]]; then
-					echo "Automerging trivial changes in: ${rpath}/${rfile:10}"
-					mv ${rpath}/${rfile} ${rpath}/${rfile:10}
+
+				if [[ ${MATCHES} == 1 ]] ; then
+					echo "Automerging trivial changes in: ${live_file}"
+					mv "${cfg_file}" "${live_file}"
 					continue
 				else
-					count=${count}+1
-					echo "${rpath}/${rfile:10}" > ${TMP}/files/${count}
-					echo "${rpath}/${rfile}" >> ${TMP}/files/${count}
+					: $(( ++count ))
+					echo "${live_file}" > "${TMP}"/files/${count}
+					echo "${cfg_file}" >> "${TMP}"/files/${count}
 					ofile="${rfile}"
 					opath="${rpath}"
 					continue
 				fi
 			fi
 
-			if [[ -z $(diff -Nua ${rpath}/${rfile} ${rpath}/${ofile}|
-					  grep "^[+-][^+-]"|grep -v '# .Header:.*') ]]; then
-				mv ${rpath}/${rfile} ${rpath}/${ofile}
+			if diff -Nua "${cfg_file}" "${rpath}/${ofile}" |
+				sed -n \
+					-e '/# .Header:/d' \
+					-e '/^[+-][^+-]/q1' \
+					-e '$q0'
+			then
+				mv "${cfg_file}" "${rpath}/${ofile}"
 				continue
 			else
-				echo "${rpath}/${rfile}" >> ${TMP}/files/${count}
+				echo "${cfg_file}" >> "${TMP}"/files/${count}
 				ofile="${rfile}"
 				opath="${rpath}"
 			fi
@@ -134,60 +157,63 @@ sel_file() {
 	      [[ ${input} == -1 ]] || \
 	      [[ ${input} == -3 ]]
 	do
-		local numfiles=$(ls ${TMP}/files|wc -l)
-		local numwidth=${#numfiles}
-		for file in $(ls ${TMP}/files|sort -n); do
-			if [[ ${isfirst} == 0 ]] ; then
-				isfirst=${file}
-			fi
-			numshow=$(printf "%${numwidth}i${PAR} " ${file})
-			numupdates=$(( $(wc -l <${TMP}/files/${file}) - 1 ))
-			echo -n "${numshow}"
-			if [[ ${mode} == 0 ]] ; then
-				echo "$(head -n1 ${TMP}/files/${file}) (${numupdates})"
-			else
-				head -n1 ${TMP}/files/${file}
-			fi
-		done > ${TMP}/menuitems
+		local allfiles=( $(cd "${TMP}"/files/ && printf '%s\n' * | sort -n) )
+		local isfirst=${allfiles[0]}
 
-		if [ "${OVERWRITE_ALL}" == "yes" ]; then
-			input=0
-		elif [ "${DELETE_ALL}" == "yes" ]; then
+		# Optimize: no point in building the whole file list if
+		# we're not actually going to talk to the user.
+		if [[ ${OVERWRITE_ALL} == "yes" || ${DELETE_ALL} == "yes" ]] ; then
 			input=0
 		else
-			[[ $CLEAR_TERM == yes ]] && clear
-			if [[ ${mode} == 0 ]] ; then
-				echo "The following is the list of files which need updating, each
-configuration file is followed by a list of possible replacement files."
-			else
-				local my_title="Please select a file to update"
-			fi
+			local numfiles=${#allfiles[@]}
+			local numwidth=${#numfiles}
+			local file fullfile line
+			for file in "${allfiles[@]}" ; do
+				fullfile="${TMP}/files/${file}"
+				line=$(head -n1 "${fullfile}")
+				printf '%*i%s %s' ${numwidth} ${file} "${PAR}" "${line}"
+				if [[ ${mode} == 0 ]] ; then
+					local numupdates=$(( $(wc -l <"${fullfile}") - 1 ))
+					echo " (${numupdates})"
+				else
+					echo
+				fi
+			done > "${TMP}"/menuitems
+
+			clear
 
 			if [[ ${mode} == 0 ]] ; then
-				cat ${TMP}/menuitems
-				echo    "Please select a file to edit by entering the corresponding number."
-				echo    "              (don't use -3, -5, -7 or -9 if you're unsure what to do)"
-				echo    "              (-1 to exit) (-3 to auto merge all remaining files)"
-				echo    "                           (-5 to auto-merge AND not use 'mv -i')"
-				echo    "                           (-7 to discard all updates)"
-				echo -n "                           (-9 to discard all updates AND not use 'rm -i'): "
+				cat <<-EOF
+					The following is the list of files which need updating, each
+					configuration file is followed by a list of possible replacement files.
+					$(<"${TMP}"/menuitems)
+					Please select a file to edit by entering the corresponding number.
+					              (don't use -3, -5, -7 or -9 if you're unsure what to do)
+					              (-1 to exit) (-3 to auto merge all remaining files)
+					                           (-5 to auto-merge AND not use 'mv -i')
+					                           (-7 to discard all updates)
+				EOF
+				printf "                           (-9 to discard all updates AND not use 'rm -i'): "
 				input=$(read_int)
 			else
-				dialog --title "${title}" --menu "${my_title}" \
-					0 0 0 $(echo -e "-1 Exit\n$(<${TMP}/menuitems)") \
-					2> ${TMP}/input || die "User termination!" 0
-				input=$(<${TMP}/input)
+				dialog \
+					--title "${title}" \
+					--menu "Please select a file to update"	\
+					0 0 0 $(<"${TMP}"/menuitems) \
+					2> "${TMP}"/input \
+					|| die "$(<"${TMP}"/input)\n\nUser termination!" 0
+				input=$(<"${TMP}"/input)
 			fi
-			if [[ ${input} == -9 ]]; then
-				read -p "Are you sure that you want to delete all updates (type YES):" reply
-				if [[ ${reply} != "YES" ]]; then
+			if [[ ${input} == -9 ]] ; then
+				read -p "Are you sure that you want to delete all updates (type YES): " reply
+				if [[ ${reply} != "YES" ]] ; then
 					continue
 				else
 					input=-7
 					export rm_opts=""
 				fi
 			fi
-			if [[ ${input} == -7 ]]; then
+			if [[ ${input} == -7 ]] ; then
 				input=0
 				export DELETE_ALL="yes"
 			fi
@@ -201,21 +227,24 @@ configuration file is followed by a list of possible replacement files."
 				export OVERWRITE_ALL="yes"
 			fi
 		fi # -3 automerge
-		if [[ -z ${input} ]] || [[ ${input} == 0 ]] ; then
+		if [[ ${input:-0} == 0 ]] ; then
 			input=${isfirst}
 		fi
 	done
 }
 
 user_special() {
-	if [ -r ${PORTAGE_CONFIGROOT}etc/etc-update.special ]; then
-		if [ -z "$1" ]; then
-			echo "ERROR: user_special() called without arguments"
+	local special="${PORTAGE_CONFIGROOT}etc/etc-update.special"
+
+	if [[ -r ${special} ]] ; then
+		if [[ -z $1 ]] ; then
+			error "user_special() called without arguments"
 			return 1
 		fi
-		while read -r pat; do
-			echo ${1} | grep "${pat}" > /dev/null && return 0
-		done < ${PORTAGE_CONFIGROOT}etc/etc-update.special
+		local pat
+		while read -r pat ; do
+			echo "$1" | grep -q "${pat}" && return 0
+		done < "${special}"
 	fi
 	return 1
 }
@@ -225,12 +254,12 @@ read_int() {
 	# read.  This is a workaround for odd behavior of bash when an attempt is
 	# made to store a value such as "1y" into an integer-only variable.
 	local my_input
-	while true; do
+	while : ; do
 		read my_input
 		# failed integer conversions will break a loop unless they're enclosed
 		# in a subshell.
-		echo "${my_input}" | ( declare -i x; read x) 2>/dev/null && break
-		echo -n "Value '$my_input' is not valid. Please enter an integer value:" >&2
+		echo "${my_input}" | (declare -i x; read x) 2>/dev/null && break
+		printf 'Value "%s" is not valid. Please enter an integer value: ' "${my_input}" >&2
 	done
 	echo ${my_input}
 }
@@ -239,141 +268,147 @@ do_file() {
 	interactive_echo() { [ "${OVERWRITE_ALL}" != "yes" ] && [ "${DELETE_ALL}" != "yes" ] && echo; }
 	interactive_echo
 	local -i my_input
-	local -i fcount=0
-	until (( $(wc -l < ${TMP}/files/${input}) < 2 )); do
-		my_input=0
-		if (( $(wc -l < ${TMP}/files/${input}) == 2 )); then
+	local -i linecnt
+	local fullfile="${TMP}/files/${input}"
+	local ofile=$(head -n1 "${fullfile}")
+
+	# Walk through all the pending updates for this one file.
+	linecnt=$(wc -l <"${fullfile}")
+	while (( linecnt > 1 )) ; do
+		if (( linecnt == 2 )) ; then
+			# Only one update ... keeps things simple.
 			my_input=1
+		else
+			my_input=0
 		fi
-		until (( ${my_input} > 0 )) && (( ${my_input} < $(wc -l < ${TMP}/files/${input}) )); do
-			fcount=0
 
-			if [ "${OVERWRITE_ALL}" == "yes" ]; then
-				my_input=0
-			elif [ "${DELETE_ALL}" == "yes" ]; then
-				my_input=0
-			else
-				for line in $(<${TMP}/files/${input}); do
-					if (( ${fcount} > 0 )); then
-						echo -n "${fcount}${PAR} "
-						echo "${line}"
-					else
-						if [[ ${mode} == 0 ]] ; then
-							echo "Below are the new config files for ${line}:"
-						else
-							local my_title="Please select a file to process for ${line}"
-						fi
-					fi
-					fcount=${fcount}+1
-				done > ${TMP}/menuitems
+		# Optimize: no point in scanning the file list when we know
+		# we're just going to consume all the ones available.
+		if [[ ${OVERWRITE_ALL} == "yes" || ${DELETE_ALL} == "yes" ]] ; then
+			my_input=1
+		fi
 
-				if [[ ${mode} == 0 ]] ; then
-					cat ${TMP}/menuitems
-					echo -n "Please select a file to process (-1 to exit this file): "
-					my_input=$(read_int)
-				else
-					dialog --title "${title}" --menu "${my_title}" \
-						0 0 0 $(echo -e "$(<${TMP}/menuitems)\n${fcount} Exit") \
-						2> ${TMP}/input || die "User termination!" 0
-					my_input=$(<${TMP}/input)
+		# Figure out which file they wish to operate on.
+		while (( my_input <= 0 || my_input >= linecnt )) ; do
+			local fcount=0
+			for line in $(<"${fullfile}"); do
+				if (( fcount > 0 )); then
+					printf '%i%s %s\n' ${fcount} "${PAR}" "${line}"
 				fi
-			fi # OVERWRITE_ALL
+				: $(( ++fcount ))
+			done > "${TMP}"/menuitems
+
+			if [[ ${mode} == 0 ]] ; then
+				echo "Below are the new config files for ${ofile}:"
+				cat "${TMP}"/menuitems
+				echo -n "Please select a file to process (-1 to exit this file): "
+				my_input=$(read_int)
+			else
+				dialog \
+					--title "${title}" \
+					--menu "Please select a file to process for ${ofile}" \
+					0 0 0 $(<"${TMP}"/menuitems) \
+					2> "${TMP}"/input \
+					|| die "$(<"${TMP}"/input)\n\nUser termination!" 0
+				my_input=$(<"${TMP}"/input)
+			fi
 
 			if [[ ${my_input} == 0 ]] ; then
+				# Auto select the first file.
 				my_input=1
 			elif [[ ${my_input} == -1 ]] ; then
 				input=0
 				return
-			elif [[ ${my_input} == ${fcount} ]] ; then
-				break
 			fi
 		done
-		if [[ ${my_input} == ${fcount} ]] ; then
-			break
-		fi
-
-		fcount=${my_input}+1
-
-		file=$(sed -e "${fcount}p;d" ${TMP}/files/${input})
-		ofile=$(head -n1 ${TMP}/files/${input})
 
+		# First line is the old file while the rest are the config files.
+		: $(( ++my_input ))
+		local file=$(sed -n -e "${my_input}p" "${fullfile}")
 		do_cfg "${file}" "${ofile}"
 
-		sed -e "${fcount}!p;d" ${TMP}/files/${input} > ${TMP}/files/sed
-		mv ${TMP}/files/sed ${TMP}/files/${input}
+		sed -i -e "${my_input}d" "${fullfile}"
 
-		if [[ ${my_input} == -1 ]] ; then
-			break
-		fi
+		: $(( --linecnt ))
 	done
+
 	interactive_echo
-	rm ${TMP}/files/${input}
-	count=${count}-1
+	rm "${fullfile}"
+	: $(( --count ))
 }
 
-do_cfg() {
+show_diff() {
+	clear
+	local file1=$1 file2=$2
+	if [[ ${using_editor} == 0 ]] ; then
+		(
+			echo "Showing differences between ${file1} and ${file2}"
+			diff_command "${file1}" "${file2}"
+		) | ${pager}
+	else
+		echo "Beginning of differences between ${file1} and ${file2}"
+		diff_command "${file1}" "${file2}"
+		echo "End of differences between ${file1} and ${file2}"
+	fi
+}
 
-	local file="${1}"
-	local ofile="${2}"
+do_cfg() {
+	local file=$1
+	local ofile=$2
 	local -i my_input=0
 
-	until (( ${my_input} == -1 )) || [ ! -f ${file} ]; do
+	until (( my_input == -1 )) || [ ! -f ${file} ] ; do
 		if [[ "${OVERWRITE_ALL}" == "yes" ]] && ! user_special "${ofile}"; then
 			my_input=1
 		elif [[ "${DELETE_ALL}" == "yes" ]] && ! user_special "${ofile}"; then
 			my_input=2
 		else
-			[[ $CLEAR_TERM == yes ]] && clear
-			if [ "${using_editor}" == 0 ]; then
-				(
-					echo "Showing differences between ${ofile} and ${file}"
-					diff_command "${ofile}" "${file}"
-				) | ${pager}
-			else
-				echo "Beginning of differences between ${ofile} and ${file}"
-				diff_command "${ofile}" "${file}"
-				echo "End of differences between ${ofile} and ${file}"
-			fi
-			if [ -L "${file}" ]; then
-				echo
-				echo "-------------------------------------------------------------"
-				echo "NOTE: File is a symlink to another file. REPLACE recommended."
-				echo "      The original file may simply have moved. Please review."
-				echo "-------------------------------------------------------------"
-				echo
+			show_diff "${ofile}" "${file}"
+			if [[ -L ${file} ]] ; then
+				cat <<-EOF
+
+					-------------------------------------------------------------
+					NOTE: File is a symlink to another file. REPLACE recommended.
+					      The original file may simply have moved. Please review.
+					-------------------------------------------------------------
+
+				EOF
 			fi
-			echo -n "File: ${file}
-1) Replace original with update
-2) Delete update, keeping original as is
-3) Interactively merge original with update
-4) Show differences again
-5) Save update as example config
-Please select from the menu above (-1 to ignore this update): "
+			cat <<-EOF
+
+				File: ${file}
+				1) Replace original with update
+				2) Delete update, keeping original as is
+				3) Interactively merge original with update
+				4) Show differences again
+				5) Save update as example config
+			EOF
+			printf 'Please select from the menu above (-1 to ignore this update): '
 			my_input=$(read_int)
 		fi
 
 		case ${my_input} in
-			1) echo "Replacing ${ofile} with ${file}"
-			   mv ${mv_opts} ${file} ${ofile}
-			   [ -n "${OVERWRITE_ALL}" ] && my_input=-1
-			   continue
-			   ;;
-			2) echo "Deleting ${file}"
-			   rm ${rm_opts} ${file}
-			   [ -n "${DELETE_ALL}" ] && my_input=-1
-			   continue
-			   ;;
-			3) do_merge "${file}" "${ofile}"
-			   my_input=${?}
-#			   [ ${my_input} == 255 ] && my_input=-1
-			   continue
-			   ;;
-			4) continue
-			   ;;
-			5) do_distconf "${file}" "${ofile}"
-			   ;;
-			*) continue
-			   ;;
+			1)	echo "Replacing ${ofile} with ${file}"
+				mv ${mv_opts} ${file} ${ofile}
+				[ -n "${OVERWRITE_ALL}" ] && my_input=-1
+				continue
+				;;
+			2)	echo "Deleting ${file}"
+				rm ${rm_opts} ${file}
+				[ -n "${DELETE_ALL}" ] && my_input=-1
+				continue
+				;;
+			3)	do_merge "${file}" "${ofile}"
+				my_input=${?}
+#				[ ${my_input} == 255 ] && my_input=-1
+				continue
+				;;
+			4)	continue
+				;;
+			5)	do_distconf "${file}" "${ofile}"
+				;;
+			*)	continue
+				;;
 		esac
 	done
 }
@@ -399,57 +434,48 @@ do_merge() {
 	# need to make sure the full /path/to/ exists ahead of time
 	mkdir -p "${mfile%/*}"
 
-	until (( ${my_input} == -1 )); do
+	until (( my_input == -1 )); do
 		echo "Merging ${file} and ${ofile}"
 		$(echo "${merge_command}" |
 		 sed -e "s:%merged:${mfile}:g" \
 		 	 -e "s:%orig:${ofile}:g" \
 			 -e "s:%new:${file}:g")
-		until (( ${my_input} == -1 )); do
-			echo -n "1) Replace ${ofile} with merged file
-2) Show differences between merged file and original
-3) Remerge original with update
-4) Edit merged file
-5) Return to the previous menu
-Please select from the menu above (-1 to exit, losing this merge): "
+		until (( my_input == -1 )); do
+			cat <<-EOF
+				1) Replace ${ofile} with merged file
+				2) Show differences between merged file and original
+				3) Remerge original with update
+				4) Edit merged file
+				5) Return to the previous menu
+			EOF
+			printf 'Please select from the menu above (-1 to exit, losing this merge): '
 			my_input=$(read_int)
 			case ${my_input} in
-				1) echo "Replacing ${ofile} with ${mfile}"
-				   if  [[ ${USERLAND} == BSD ]] ; then
-				       chown "$(stat -f %Su:%Sg "${ofile}")" "${mfile}"
-				       chmod $(stat -f %Mp%Lp "${ofile}") "${mfile}"
-				   else
-				       chown --reference="${ofile}" "${mfile}"
-				       chmod --reference="${ofile}" "${mfile}"
-				   fi
-				   mv ${mv_opts} "${mfile}" "${ofile}"
-				   rm ${rm_opts} "${file}"
-				   return 255
-				   ;;
-				2)
-					[[ $CLEAR_TERM == yes ]] && clear
-					if [ "${using_editor}" == 0 ]; then
-						(
-							echo "Showing differences between ${ofile} and ${mfile}"
-							diff_command "${ofile}" "${mfile}"
-						) | ${pager}
+				1)	echo "Replacing ${ofile} with ${mfile}"
+					if [[ ${USERLAND} == BSD ]] ; then
+						chown "$(stat -f %Su:%Sg "${ofile}")" "${mfile}"
+						chmod $(stat -f %Mp%Lp "${ofile}") "${mfile}"
 					else
-						echo "Beginning of differences between ${ofile} and ${mfile}"
-						diff_command "${ofile}" "${mfile}"
-						echo "End of differences between ${ofile} and ${mfile}"
+						chown --reference="${ofile}" "${mfile}"
+						chmod --reference="${ofile}" "${mfile}"
 					fi
-				   continue
-				   ;;
-				3) break
-				   ;;
-				4) ${EDITOR:-nano -w} "${mfile}"
-				   continue
-					 ;;
-				5) rm ${rm_opts} "${mfile}"
-				   return 0
-				   ;;
-				*) continue
-				   ;;
+					mv ${mv_opts} "${mfile}" "${ofile}"
+					rm ${rm_opts} "${file}"
+					return 255
+					;;
+				2)	show_diff "${ofile}" "${mfile}"
+					continue
+					;;
+				3)	break
+					;;
+				4)	${EDITOR:-nano -w} "${mfile}"
+					continue
+					;;
+				5)	rm ${rm_opts} "${mfile}"
+					return 0
+					;;
+				*)	continue
+					;;
 			esac
 		done
 	done
@@ -461,21 +487,15 @@ do_distconf() {
 	# search for any previously saved distribution config
 	# files and number the current one accordingly
 
-	local file="${1}"
-	local ofile="${2}"
+	local file=$1 ofile=$2
 	local -i count
-	local -i fill
 	local suffix
 	local efile
 
-	for ((count = 0; count <= 9999; count++)); do
-		suffix=".dist_"
-		for ((fill = 4 - ${#count}; fill > 0; fill--)); do
-			suffix+="0"
-		done
-		suffix+="${count}"
+	for (( count = 0; count <= 9999; ++count )) ; do
+		suffix=$(printf ".dist_%04i" ${count})
 		efile="${ofile}${suffix}"
-		if [[ ! -f ${efile} ]]; then
+		if [[ ! -f ${efile} ]] ; then
 			mv ${mv_opts} "${file}" "${efile}"
 			break
 		elif diff_command "${file}" "${efile}" &> /dev/null; then
@@ -486,20 +506,22 @@ do_distconf() {
 	done
 }
 
+error() { echo "etc-update: ERROR: $*" 1>&2 ; return 1 ; }
 die() {
 	trap SIGTERM
 	trap SIGINT
+	local msg=$1 exitcode=${2:-1}
 
-	if [ "$2" -eq 0 ]; then
-		echo "Exiting: ${1}"
+	if [ ${exitcode} -eq 0 ] ; then
+		printf 'Exiting: %b\n' "${msg}"
 		scan > /dev/null
 		[ ${count} -gt 0 ] && echo "NOTE: ${count} updates remaining"
 	else
-		echo "ERROR: ${1}"
+		error "${msg}"
 	fi
 
 	rm -rf "${TMP}"
-	exit ${2}
+	exit ${exitcode}
 }
 
 usage() {
@@ -511,10 +533,11 @@ usage() {
 	Options:
 	  -d, --debug    Enable shell debugging
 	  -h, --help     Show help and run away
+	  -v, --verbose  Show settings and such along the way
 	  -V, --version  Show version and trundle away
 	EOF
 
-	[[ -n ${*:2} ]] && printf "\nError: %s\n" "${*:2}" 1>&2
+	[[ $# -gt 1 ]] && printf "\nError: %s\n" "${*:2}" 1>&2
 
 	exit ${1:-0}
 }
@@ -524,10 +547,12 @@ usage() {
 #
 
 SET_X=false
+VERBOSE=false
 while [[ -n $1 ]] ; do
 	case $1 in
 		-d|--debug)   SET_X=true;;
 		-h|--help)    usage;;
+		-v|--verbose) VERBOSE=true;;
 		-V|--version) emerge --version ; exit 0;;
 		*)            usage 1 "Invalid option '$1'";;
 	esac
@@ -535,77 +560,85 @@ while [[ -n $1 ]] ; do
 done
 ${SET_X} && set -x
 
-type portageq > /dev/null || exit $?
-eval $(portageq envvar -v CONFIG_PROTECT \
-	CONFIG_PROTECT_MASK PORTAGE_CONFIGROOT PORTAGE_INST_GID PORTAGE_INST_UID \
-	PORTAGE_TMPDIR EROOT USERLAND)
+type portageq >/dev/null || die "missing portageq"
+portage_vars=(
+	CONFIG_PROTECT{,_MASK}
+	PORTAGE_CONFIGROOT
+	PORTAGE_INST_{G,U}ID
+	PORTAGE_TMPDIR
+	EROOT
+	USERLAND
+	NOCOLOR
+)
+eval $(portageq envvar -v ${portage_vars[@]})
 export PORTAGE_TMPDIR
 
 TMP="${PORTAGE_TMPDIR}/etc-update-$$"
-trap "die terminated 1" SIGTERM
-trap "die interrupted 1" SIGINT
-
-[ -w ${PORTAGE_CONFIGROOT}etc ] || die "Need write access to ${PORTAGE_CONFIGROOT}etc" 1
-#echo $PORTAGE_TMPDIR
-#echo $CONFIG_PROTECT
-#echo $CONFIG_PROTECT_MASK
-#export PORTAGE_TMPDIR=$(/usr/lib/portage/bin/portageq envvar PORTAGE_TMPDIR)
+trap "die terminated" SIGTERM
+trap "die interrupted" SIGINT
 
-rm -rf "${TMP}" 2> /dev/null
-mkdir "${TMP}" || die "failed to create temp dir" 1
+rm -rf "${TMP}" 2>/dev/null
+mkdir "${TMP}" || die "failed to create temp dir"
 # make sure we have a secure directory to work in
-chmod 0700 "${TMP}" || die "failed to set perms on temp dir" 1
+chmod 0700 "${TMP}" || die "failed to set perms on temp dir"
 chown ${PORTAGE_INST_UID:-0}:${PORTAGE_INST_GID:-0} "${TMP}" || \
-	die "failed to set ownership on temp dir" 1
-
-# I need the CONFIG_PROTECT value
-#CONFIG_PROTECT=$(/usr/lib/portage/bin/portageq envvar CONFIG_PROTECT)
-#CONFIG_PROTECT_MASK=$(/usr/lib/portage/bin/portageq envvar CONFIG_PROTECT_MASK)
-
-# load etc-config's configuration
-CLEAR_TERM=$(get_config clear_term)
-EU_AUTOMERGE=$(get_config eu_automerge)
-rm_opts=$(get_config rm_opts)
-mv_opts=$(get_config mv_opts)
-cp_opts=$(get_config cp_opts)
-pager=$(get_config pager)
-diff_command=$(get_config diff_command)
-using_editor=$(get_config using_editor)
-merge_command=$(get_config merge_command)
-declare -i mode=$(get_config mode)
-[[ -z ${mode} ]] && mode=0
+	die "failed to set ownership on temp dir"
+
+# Get all the user settings from etc-update.conf
+cfg_vars=(
+	using_editor
+	clear_term
+	eu_automerge
+	rm_opts
+	mv_opts
+	pager
+	diff_command
+	using_editor
+	merge_command
+	mode
+)
+# default them all to ""
+eval ${cfg_vars[@]/%/=}
+# then extract them all from the conf in one shot
+# (ugly var at end is due to printf appending a '|' to last item)
+get_config "($(printf '%s|' "${cfg_vars[@]}")NOVARFOROLDMEN)"
+
+# finally setup any specific defaults
+: ${mode:="0"}
 if ! cmd_var_is_valid "${pager}" ; then
 	pager=${PAGER}
 	cmd_var_is_valid "${pager}" || pager=cat
 fi
 
-if [ "${using_editor}" == 0 ]; then
+[[ ${clear_term} == "yes" ]] || clear() { :; }
+
+if [[ ${using_editor} == "0" ]] ; then
 	# Sanity check to make sure diff exists and works
 	echo > "${TMP}"/.diff-test-1
 	echo > "${TMP}"/.diff-test-2
-	
+
 	if ! diff_command "${TMP}"/.diff-test-1 "${TMP}"/.diff-test-2 ; then
-		die "'${diff_command}' does not seem to work, aborting" 1
+		die "'${diff_command}' does not seem to work, aborting"
 	fi
 else
-	if ! type ${diff_command%% *} >/dev/null; then
-		die "'${diff_command}' does not seem to work, aborting" 1
+	if ! cmd_var_is_valid "${diff_command}" ; then
+		die "'${diff_command}' does not seem to work, aborting"
 	fi
 fi
 
-if [[ ${mode} == "1" ]] ; then
+if [[ ${mode} == "0" ]] ; then
+	PAR=")"
+else
+	PAR=""
 	if ! type dialog >/dev/null || ! dialog --help >/dev/null ; then
-		die "mode=1 and 'dialog' not found or not executable, aborting" 1
+		die "mode=1 and 'dialog' not found or not executable, aborting"
 	fi
 fi
 
-#echo "rm_opts: $rm_opts, mv_opts: $mv_opts, cp_opts: $cp_opts"
-#echo "pager: $pager, diff_command: $diff_command, merge_command: $merge_command"
-
-if (( ${mode} == 0 )); then
-	PAR=")"
-else
-	PAR=""
+if ${VERBOSE} ; then
+	for v in ${portage_vars[@]} ${cfg_vars[@]} TMP ; do
+		echo "${v}=${!v}"
+	done
 fi
 
 declare -i count=0
@@ -614,12 +647,12 @@ declare title="Gentoo's etc-update tool!"
 
 scan
 
-until (( ${input} == -1 )); do
-	if (( ${count} == 0 )); then
+until (( input == -1 )); do
+	if (( count == 0 )); then
 		die "Nothing left to do; exiting. :)" 0
 	fi
 	sel_file
-	if (( ${input} != -1 )); then
+	if (( input != -1 )); then
 		do_file
 	fi
 done