From 0e037b8c45db499e199299cb8079aaa8b5c45371 Mon Sep 17 00:00:00 2001
From: Avery Pennarun <apenwarr@gmail.com>
Date: Sat, 5 Mar 2011 18:48:27 -0800
Subject: [PATCH] minimal/do: leak fewer variables, especially PREFIX.

Since we use ". filename.do" to run the .do files instead of just
"filename.do", shell local variables end up being inherited by the
subprogram.  Change all the local variables to be all lowercase, to avoid
conflicting with any typical environment variables someone might use.

The particular variable that triggered this was PREFIX (reported by "ulrik"
on the mailing list) and that fixes this, at least.

Arguably we shouldn't be using ".", but using it avoids unnecessary forks,
which is kind of nice.
---
 minimal/do | 88 +++++++++++++++++++++++++++---------------------------
 1 file changed, 44 insertions(+), 44 deletions(-)

diff --git a/minimal/do b/minimal/do
index 5bde592..fdd2bf6 100755
--- a/minimal/do
+++ b/minimal/do
@@ -8,14 +8,14 @@
 #
 
 # By default, no output coloring.
-GREEN=""
-BOLD=""
-PLAIN=""
+green=""
+bold=""
+plain=""
 
 if [ -n "$TERM" -a "$TERM" != "dumb" ] && tty <&2 >/dev/null 2>&1; then
-	GREEN="$(printf '\033[32m')"
-	BOLD="$(printf '\033[1m')"
-	PLAIN="$(printf '\033[m')"
+	green="$(printf '\033[32m')"
+	bold="$(printf '\033[1m')"
+	plain="$(printf '\033[m')"
 fi
 
 _dirsplit()
@@ -54,78 +54,78 @@ fi
 
 _find_dofile_pwd()
 {
-	DOFILE=default.$1.do
+	dofile=default.$1.do
 	while :; do
-		DOFILE=default.${DOFILE#default.*.}
-		[ -e "$DOFILE" -o "$DOFILE" = default.do ] && break
+		dofile=default.${dofile#default.*.}
+		[ -e "$dofile" -o "$dofile" = default.do ] && break
 	done
-	EXT=${DOFILE#default}
-	EXT=${EXT%.do}
-	BASE=${1%$EXT}
+	ext=${dofile#default}
+	ext=${ext%.do}
+	base=${1%$ext}
 }
 
 
 _find_dofile()
 {
-	PREFIX=
+	local prefix=
 	while :; do
 		_find_dofile_pwd "$1"
-		[ -e "$DOFILE" ] && break
+		[ -e "$dofile" ] && break
 		[ "$PWD" = "/" ] && break
-		TARGET=${PWD##*/}/$TARGET
-		PREFIX=${PWD##*/}/$PREFIX
+		target=${PWD##*/}/$target
+		prefix=${PWD##*/}/$prefix
 		cd ..
 	done
-	BASE=$PREFIX$BASE
+	base=$prefix$base
 }
 
 
 _run_dofile()
 {
 	export DO_DEPTH="$DO_DEPTH  "
-	export REDO_TARGET=$PWD/$TARGET
+	export REDO_TARGET=$PWD/$target
+	local line1
 	set -e
-	read line1 <"$PWD/$DOFILE"
+	read line1 <"$PWD/$dofile"
 	cmd=${line1#"#!/"}
 	if [ "$cmd" != "$line1" ]; then
-		/$cmd "$PWD/$DOFILE" "$@" >"$TARGET.tmp2"
+		/$cmd "$PWD/$dofile" "$@" >"$target.tmp2"
 	else
-		:; . "$PWD/$DOFILE" >"$TARGET.tmp2"
+		:; . "$PWD/$dofile" >"$target.tmp2"
 	fi
 }
 
 
 _do()
 {
-	DIR=$1
-	TARGET=$2
-	if [ ! -e "$TARGET" ] || [ -d "$TARGET/." -a ! -e "$TARGET.did" ]; then
+	local dir=$1 target=$2
+	if [ ! -e "$target" ] || [ -d "$target/." -a ! -e "$target.did" ]; then
 		printf '%sdo  %s%s%s%s\n' \
-			"$GREEN" "$DO_DEPTH" "$BOLD" "$DIR$TARGET" "$PLAIN" >&2
-		echo "$PWD/$TARGET" >>"$DO_BUILT"
-		DOFILE=$TARGET.do
-		BASE=$TARGET
-		EXT=
-		[ -e "$TARGET.do" ] || _find_dofile "$TARGET"
-		if [ ! -e "$DOFILE" ]; then
-			echo "do: $TARGET: no .do file" >&2
+			"$green" "$DO_DEPTH" "$bold" "$dir$target" "$plain" >&2
+		echo "$PWD/$target" >>"$DO_BUILT"
+		dofile=$target.do
+		base=$target
+		ext=
+		[ -e "$target.do" ] || _find_dofile "$target"
+		if [ ! -e "$dofile" ]; then
+			echo "do: $target: no .do file" >&2
 			return 1
 		fi
-		[ ! -e "$DO_BUILD" ] || : >>"$TARGET.did"
-		( _run_dofile "$BASE" "$EXT" "$TARGET.tmp" )
-		RV=$?
-		if [ $RV != 0 ]; then
+		[ ! -e "$DO_BUILD" ] || : >>"$target.did"
+		( _run_dofile "$base" "$ext" "$target.tmp" )
+		rv=$?
+		if [ $rv != 0 ]; then
 			printf "do: %s%s\n" "$DO_DEPTH" \
-				"$DIR$TARGET: got exit code $RV" >&2
-			rm -f "$TARGET.tmp" "$TARGET.tmp2"
-			return $RV
+				"$dir$target: got exit code $rv" >&2
+			rm -f "$target.tmp" "$target.tmp2"
+			return $rv
 		fi
-		mv "$TARGET.tmp" "$TARGET" 2>/dev/null ||
-		! test -s "$TARGET.tmp2" ||
-		mv "$TARGET.tmp2" "$TARGET" 2>/dev/null
-		rm -f "$TARGET.tmp2"
+		mv "$target.tmp" "$target" 2>/dev/null ||
+		! test -s "$target.tmp2" ||
+		mv "$target.tmp2" "$target" 2>/dev/null
+		rm -f "$target.tmp2"
 	else
-		echo "do  $DO_DEPTH$TARGET exists." >&2
+		echo "do  $DO_DEPTH$target exists." >&2
 	fi
 }