xref: /openbmc/u-boot/scripts/objdiff (revision 35546f6f2014282cc4f9772324b5588bd44a2938)
1 #!/bin/bash
2 
3 # objdiff - a small script for validating that a commit or series of commits
4 # didn't change object code.
5 #
6 # Copyright 2014, Jason Cooper <jason@lakedaemon.net>
7 #
8 # Licensed under the terms of the GNU GPL version 2
9 
10 # usage example:
11 #
12 # $ git checkout COMMIT_A
13 # $ <your fancy build command here>
14 # $ ./scripts/objdiff record path/to/*.o
15 #
16 # $ git checkout COMMIT_B
17 # $ <your fancy build command here>
18 # $ ./scripts/objdiff record path/to/*.o
19 #
20 # $ ./scripts/objdiff diff COMMIT_A COMMIT_B
21 # $
22 
23 # And to clean up (everything is in .tmp_objdiff/*)
24 # $ ./scripts/objdiff clean all
25 #
26 # Note: 'make mrproper' will also remove .tmp_objdiff
27 
28 SRCTREE=$(cd $(git rev-parse --show-toplevel 2>/dev/null); pwd)
29 
30 if [ -z "$SRCTREE" ]; then
31 	echo >&2 "ERROR: Not a git repository."
32 	exit 1
33 fi
34 
35 TMPD=$SRCTREE/.tmp_objdiff
36 
37 usage() {
38 	echo >&2 "Usage: $0 <command> <args>"
39 	echo >&2 "  record    <list of object files or directories>"
40 	echo >&2 "  diff      <commitA> <commitB>"
41 	echo >&2 "  clean     all | <commit>"
42 	exit 1
43 }
44 
45 get_output_dir() {
46 	dir=${1%/*}
47 
48 	if [ "$dir" = "$1" ]; then
49 		dir=.
50 	fi
51 
52 	dir=$(cd $dir; pwd)
53 
54 	echo $TMPD/$CMT${dir#$SRCTREE}
55 }
56 
57 do_objdump() {
58 	dir=$(get_output_dir $1)
59 	base=${1##*/}
60 	dis=$dir/${base%.o}.dis
61 
62 	[ ! -d "$dir" ] && mkdir -p $dir
63 
64 	# remove addresses for a cleaner diff
65 	# http://dummdida.tumblr.com/post/60924060451/binary-diff-between-libc-from-scientificlinux-and
66 	$OBJDUMP -D $1 | sed "s/^[[:space:]]\+[0-9a-f]\+//" > $dis
67 }
68 
69 dorecord() {
70 	[ $# -eq 0 ] && usage
71 
72 	FILES="$*"
73 
74 	CMT="`git rev-parse --short HEAD`"
75 
76 	OBJDUMP="${CROSS_COMPILE}objdump"
77 
78 	for d in $FILES; do
79 		if [ -d "$d" ]; then
80 			for f in $(find $d -name '*.o')
81 			do
82 				do_objdump $f
83 			done
84 		else
85 			do_objdump $d
86 		fi
87 	done
88 }
89 
90 dodiff() {
91 	[ $# -ne 2 ] && [ $# -ne 0 ] && usage
92 
93 	if [ $# -eq 0 ]; then
94 		SRC="`git rev-parse --short HEAD^`"
95 		DST="`git rev-parse --short HEAD`"
96 	else
97 		SRC="`git rev-parse --short $1`"
98 		DST="`git rev-parse --short $2`"
99 	fi
100 
101 	DIFF="`which colordiff`"
102 
103 	if [ ${#DIFF} -eq 0 ] || [ ! -x "$DIFF" ]; then
104 		DIFF="`which diff`"
105 	fi
106 
107 	SRCD="$TMPD/$SRC"
108 	DSTD="$TMPD/$DST"
109 
110 	if [ ! -d "$SRCD" ]; then
111 		echo >&2 "ERROR: $SRCD doesn't exist"
112 		exit 1
113 	fi
114 
115 	if [ ! -d "$DSTD" ]; then
116 		echo >&2 "ERROR: $DSTD doesn't exist"
117 		exit 1
118 	fi
119 
120 	$DIFF -Nurd $SRCD $DSTD
121 }
122 
123 doclean() {
124 	[ $# -eq 0 ] && usage
125 	[ $# -gt 1 ] && usage
126 
127 	if [ "x$1" = "xall" ]; then
128 		rm -rf $TMPD/*
129 	else
130 		CMT="`git rev-parse --short $1`"
131 
132 		if [ -d "$TMPD/$CMT" ]; then
133 			rm -rf $TMPD/$CMT
134 		else
135 			echo >&2 "$CMT not found"
136 		fi
137 	fi
138 }
139 
140 [ $# -eq 0 ] &&	usage
141 
142 case "$1" in
143 	record)
144 		shift
145 		dorecord $*
146 		;;
147 	diff)
148 		shift
149 		dodiff $*
150 		;;
151 	clean)
152 		shift
153 		doclean $*
154 		;;
155 	*)
156 		echo >&2 "Unrecognized command '$1'"
157 		exit 1
158 		;;
159 esac
160