Shell utilities: Guard against expr' magic tokens.

Some words, e.g., `match', are special to expr(1), and cause strange
parsing effects.  Track down all uses of expr and mangle the arguments
so that this isn't a problem.

Signed-off-by: Mark Wooding <mdw@distorted.org.uk>
Signed-off-by: Junio C Hamano <junkio@cox.net>

git-cherry.sh

@@ -20,7 +20,7 @@ case "$1" in -v) verbose=t; shift ;; esac
 
 case "$#,$1" in
 1,*..*)
-    upstream=$(expr "$1" : '\(.*\)\.\.') ours=$(expr "$1" : '.*\.\.\(.*\)$')
+    upstream=$(expr "z$1" : 'z\(.*\)\.\.') ours=$(expr "z$1" : '.*\.\.\(.*\)$')
     set x "$upstream" "$ours"
     shift ;;
 esac

git-clone.sh

@@ -38,12 +38,12 @@ Perhaps git-update-server-info needs to be run there?"
 	}
 	while read sha1 refname
 	do
-		name=`expr "$refname" : 'refs/\(.*\)'` &&
+		name=`expr "z$refname" : 'zrefs/\(.*\)'` &&
 		case "$name" in
 		*^*)	continue;;
 		esac
 		if test -n "$use_separate_remote" &&
-		   branch_name=`expr "$name" : 'heads/\(.*\)'`
+		   branch_name=`expr "z$name" : 'zheads/\(.*\)'`
 		then
 			tname="remotes/$origin/$branch_name"
 		else
@@ -346,7 +346,7 @@ then
 		# new style repository with a symref HEAD).
 		# Ideally we should skip the guesswork but for now
 		# opt for minimum change.
-		head_sha1=`expr "$head_sha1" : 'ref: refs/heads/\(.*\)'`
+		head_sha1=`expr "z$head_sha1" : 'zref: refs/heads/\(.*\)'`
 		head_sha1=`cat "$GIT_DIR/$remote_top/$head_sha1"`
 		;;
 	esac

git-commit.sh

@@ -549,8 +549,8 @@ fi >>"$GIT_DIR"/COMMIT_EDITMSG
 # Author
 if test '' != "$force_author"
 then
-	GIT_AUTHOR_NAME=`expr "$force_author" : '\(.*[^ ]\) *<.*'` &&
-	GIT_AUTHOR_EMAIL=`expr "$force_author" : '.*\(<.*\)'` &&
+	GIT_AUTHOR_NAME=`expr "z$force_author" : 'z\(.*[^ ]\) *<.*'` &&
+	GIT_AUTHOR_EMAIL=`expr "z$force_author" : '.*\(<.*\)'` &&
 	test '' != "$GIT_AUTHOR_NAME" &&
 	test '' != "$GIT_AUTHOR_EMAIL" ||
 	die "malformatted --author parameter"

git-fetch.sh

@@ -112,7 +112,7 @@ append_fetch_head () {
     *)
 	note_="$remote_name of " ;;
     esac
-    remote_1_=$(expr "$remote_" : '\(.*\)\.git/*$') &&
+    remote_1_=$(expr "z$remote_" : 'z\(.*\)\.git/*$') &&
 	remote_="$remote_1_"
     note_="$note_$remote_"
 
@@ -245,22 +245,22 @@ fetch_main () {
 
       # These are relative path from $GIT_DIR, typically starting at refs/
       # but may be HEAD
-      if expr "$ref" : '\.' >/dev/null
+      if expr "z$ref" : 'z\.' >/dev/null
       then
 	  not_for_merge=t
-	  ref=$(expr "$ref" : '\.\(.*\)')
+	  ref=$(expr "z$ref" : 'z\.\(.*\)')
       else
 	  not_for_merge=
       fi
-      if expr "$ref" : '\+' >/dev/null
+      if expr "z$ref" : 'z\+' >/dev/null
       then
 	  single_force=t
-	  ref=$(expr "$ref" : '\+\(.*\)')
+	  ref=$(expr "z$ref" : 'z\+\(.*\)')
       else
 	  single_force=
       fi
-      remote_name=$(expr "$ref" : '\([^:]*\):')
-      local_name=$(expr "$ref" : '[^:]*:\(.*\)')
+      remote_name=$(expr "z$ref" : 'z\([^:]*\):')
+      local_name=$(expr "z$ref" : 'z[^:]*:\(.*\)')
 
       rref="$rref$LF$remote_name"
 
@@ -276,7 +276,7 @@ fetch_main () {
 	      print "$u";
 	  ' "$remote_name")
 	  head=$(curl -nsfL $curl_extra_args "$remote/$remote_name_quoted") &&
-	  expr "$head" : "$_x40\$" >/dev/null ||
+	  expr "z$head" : "z$_x40\$" >/dev/null ||
 		  die "Failed to fetch $remote_name from $remote"
 	  echo >&2 Fetching "$remote_name from $remote" using http
 	  git-http-fetch -v -a "$head" "$remote/" || exit
@@ -362,7 +362,7 @@ fetch_main () {
 		  break ;;
 	      esac
 	  done
-	  local_name=$(expr "$found" : '[^:]*:\(.*\)')
+	  local_name=$(expr "z$found" : 'z[^:]*:\(.*\)')
 	  append_fetch_head "$sha1" "$remote" \
 		  "$remote_name" "$remote_nick" "$local_name" "$not_for_merge"
       done

git-format-patch.sh

@@ -126,8 +126,8 @@ for revpair
 do
 	case "$revpair" in
 	?*..?*)
-		rev1=`expr "$revpair" : '\(.*\)\.\.'`
-		rev2=`expr "$revpair" : '.*\.\.\(.*\)'`
+		rev1=`expr "z$revpair" : 'z\(.*\)\.\.'`
+		rev2=`expr "z$revpair" : 'z.*\.\.\(.*\)'`
 		;;
 	*)
 		rev1="$revpair^"

git-merge-one-file.sh

@@ -26,7 +26,7 @@ case "${1:-.}${2:-.}${3:-.}" in
 	fi
 	if test -f "$4"; then
 		rm -f -- "$4" &&
-		rmdir -p "$(expr "$4" : '\(.*\)/')" 2>/dev/null || :
+		rmdir -p "$(expr "z$4" : 'z\(.*\)/')" 2>/dev/null || :
 	fi &&
 		exec git-update-index --remove -- "$4"
 	;;

git-parse-remote.sh

@@ -8,8 +8,8 @@ get_data_source () {
 	case "$1" in
 	*/*)
 		# Not so fast.	This could be the partial URL shorthand...
-		token=$(expr "$1" : '\([^/]*\)/')
-		remainder=$(expr "$1" : '[^/]*/\(.*\)')
+		token=$(expr "z$1" : 'z\([^/]*\)/')
+		remainder=$(expr "z$1" : 'z[^/]*/\(.*\)')
 		if test -f "$GIT_DIR/branches/$token"
 		then
 			echo branches-partial
@@ -43,8 +43,8 @@ get_remote_url () {
 	branches)
 		sed -e 's/#.*//' "$GIT_DIR/branches/$1" ;;
 	branches-partial)
-		token=$(expr "$1" : '\([^/]*\)/')
-		remainder=$(expr "$1" : '[^/]*/\(.*\)')
+		token=$(expr "z$1" : 'z\([^/]*\)/')
+		remainder=$(expr "z$1" : 'z[^/]*/\(.*\)')
 		url=$(sed -e 's/#.*//' "$GIT_DIR/branches/$token")
 		echo "$url/$remainder"
 		;;
@@ -77,13 +77,13 @@ canon_refs_list_for_fetch () {
 		force=
 		case "$ref" in
 		+*)
-			ref=$(expr "$ref" : '\+\(.*\)')
+			ref=$(expr "z$ref" : 'z\+\(.*\)')
 			force=+
 			;;
 		esac
-		expr "$ref" : '.*:' >/dev/null || ref="${ref}:"
-		remote=$(expr "$ref" : '\([^:]*\):')
-		local=$(expr "$ref" : '[^:]*:\(.*\)')
+		expr "z$ref" : 'z.*:' >/dev/null || ref="${ref}:"
+		remote=$(expr "z$ref" : 'z\([^:]*\):')
+		local=$(expr "z$ref" : 'z[^:]*:\(.*\)')
 		case "$remote" in
 		'') remote=HEAD ;;
 		refs/heads/* | refs/tags/* | refs/remotes/*) ;;
@@ -97,7 +97,7 @@ canon_refs_list_for_fetch () {
 		*) local="refs/heads/$local" ;;
 		esac
 
-		if local_ref_name=$(expr "$local" : 'refs/\(.*\)')
+		if local_ref_name=$(expr "z$local" : 'zrefs/\(.*\)')
 		then
 		   git-check-ref-format "$local_ref_name" ||
 		   die "* refusing to create funny ref '$local_ref_name' locally"
@@ -171,7 +171,7 @@ get_remote_refs_for_fetch () {
 
 resolve_alternates () {
 	# original URL (xxx.git)
-	top_=`expr "$1" : '\([^:]*:/*[^/]*\)/'`
+	top_=`expr "z$1" : 'z\([^:]*:/*[^/]*\)/'`
 	while read path
 	do
 		case "$path" in

git-rebase.sh

@@ -94,7 +94,7 @@ case "$#" in
 	;;
 *)
 	branch_name=`git symbolic-ref HEAD` || die "No current branch"
-	branch_name=`expr "$branch_name" : 'refs/heads/\(.*\)'`
+	branch_name=`expr "z$branch_name" : 'zrefs/heads/\(.*\)'`
 	;;
 esac
 branch=$(git-rev-parse --verify "${branch_name}^0") || exit

git-tag.sh

@@ -75,7 +75,7 @@ git-check-ref-format "tags/$name" ||
 object=$(git-rev-parse --verify --default HEAD "$@") || exit 1
 type=$(git-cat-file -t $object) || exit 1
 tagger=$(git-var GIT_COMMITTER_IDENT) || exit 1
-: ${username:=$(expr "$tagger" : '\(.*>\)')}
+: ${username:=$(expr "z$tagger" : 'z\(.*>\)')}
 
 trap 'rm -f "$GIT_DIR"/TAG_TMP* "$GIT_DIR"/TAG_FINALMSG "$GIT_DIR"/TAG_EDITMSG' 0