scripts/faddr2line: make the new code listing format optional

Commit 6870c016 ("scripts/faddr2line: show the code context")
radically altered the output format of the faddr2line tool.  And while
the new list output format might have merit it broke my vim usage and
was hard to read.

Make the new format optional; using a '--list' argument and attempt to
make the output slightly easier to read by adding a little whitespace to
separate the different files and explicitly mark the line in question.

Cc: Changbin Du <changbin.du@intel.com>
Fixes: 6870c016 ("scripts/faddr2line: show the code context")
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: NJosh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

scripts/faddr2line

@@ -56,7 +56,7 @@ command -v ${SIZE} >/dev/null 2>&1 || die "size isn't installed"
 command -v ${NM} >/dev/null 2>&1 || die "nm isn't installed"
 
 usage() {
-	echo "usage: faddr2line <object file> <func+offset> <func+offset>..." >&2
+	echo "usage: faddr2line [--list] <object file> <func+offset> <func+offset>..." >&2
 	exit 1
 }
 
@@ -166,15 +166,25 @@ __faddr2line() {
 		local file_lines=$(${ADDR2LINE} -fpie $objfile $addr | sed "s; $dir_prefix\(\./\)*; ;")
 		[[ -z $file_lines ]] && return
 
+		if [[ $LIST = 0 ]]; then
+			echo "$file_lines" | while read -r line
+			do
+				echo $line
+			done
+			DONE=1;
+			return
+		fi
+
 		# show each line with context
 		echo "$file_lines" | while read -r line
 		do
+			echo
 			echo $line
 			n=$(echo $line | sed 's/.*:\([0-9]\+\).*/\1/g')
 			n1=$[$n-5]
 			n2=$[$n+5]
 			f=$(echo $line | sed 's/.*at \(.\+\):.*/\1/g')
-			awk 'NR>=strtonum("'$n1'") && NR<=strtonum("'$n2'") {printf("%d\t%s\n", NR, $0)}' $f
+			awk 'NR>=strtonum("'$n1'") && NR<=strtonum("'$n2'") { if (NR=='$n') printf(">%d<", NR); else printf(" %d ", NR); printf("\t%s\n", $0)}' $f
 		done
 
 		DONE=1
@@ -185,6 +195,10 @@ __faddr2line() {
 [[ $# -lt 2 ]] && usage
 
 objfile=$1
+
+LIST=0
+[[ "$objfile" == "--list" ]] && LIST=1 && shift && objfile=$1
+
 [[ ! -f $objfile ]] && die "can't find objfile $objfile"
 shift