summaryrefslogtreecommitdiffstats
path: root/scripts/objdiff
blob: 6e72f9645983fde612e9d4bcd8e657f7228b2b5b (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
#!/bin/bash

# objdiff - a small script for validating that a commit or series of commits
# didn't change object code.
#
# Copyright 2014, Jason Cooper <jason@lakedaemon.net>
#
# Licensed under the terms of the GNU GPL version 2

# usage example:
#
# $ git checkout COMMIT_A
# $ <your fancy build command here>
# $ ./scripts/objdiff record path/to/*.o
#
# $ git checkout COMMIT_B
# $ <your fancy build command here>
# $ ./scripts/objdiff record path/to/*.o
#
# $ ./scripts/objdiff diff COMMIT_A COMMIT_B
# $

# And to clean up (everything is in .tmp_objdiff/*)
# $ ./scripts/objdiff clean all
#
# Note: 'make mrproper' will also remove .tmp_objdiff

SRCTREE=$(git rev-parse --show-toplevel 2>/dev/null)

if [ -z "$SRCTREE" ]; then
	echo >&2 "ERROR: Not a git repository."
	exit 1
fi

TMPD=$SRCTREE/.tmp_objdiff

usage() {
	echo >&2 "Usage: $0 <command> <args>"
	echo >&2 "  record    <list of object files>"
	echo >&2 "  diff      <commitA> <commitB>"
	echo >&2 "  clean     all | <commit>"
	exit 1
}

dorecord() {
	[ $# -eq 0 ] && usage

	FILES="$*"

	CMT="`git rev-parse --short HEAD`"

	OBJDUMP="${CROSS_COMPILE}objdump"
	OBJDIFFD="$TMPD/$CMT"

	for f in $FILES; do
		dn="${f%/*}"
		bn="${f##*/}"

		[ ! -d "$OBJDIFFD/$dn" ] && mkdir -p "$OBJDIFFD/$dn"

		# remove addresses for a more clear diff
		# http://dummdida.tumblr.com/post/60924060451/binary-diff-between-libc-from-scientificlinux-and
		$OBJDUMP -D "$f" | sed "s/^[[:space:]]\+[0-9a-f]\+//" \
			>"$OBJDIFFD/$dn/$bn"
	done
}

dodiff() {
	[ $# -ne 2 ] && [ $# -ne 0 ] && usage

	if [ $# -eq 0 ]; then
		SRC="`git rev-parse --short HEAD^`"
		DST="`git rev-parse --short HEAD`"
	else
		SRC="`git rev-parse --short $1`"
		DST="`git rev-parse --short $2`"
	fi

	DIFF="`which colordiff`"

	if [ ${#DIFF} -eq 0 ] || [ ! -x "$DIFF" ]; then
		DIFF="`which diff`"
	fi

	SRCD="$TMPD/$SRC"
	DSTD="$TMPD/$DST"

	if [ ! -d "$SRCD" ]; then
		echo >&2 "ERROR: $SRCD doesn't exist"
		exit 1
	fi

	if [ ! -d "$DSTD" ]; then
		echo >&2 "ERROR: $DSTD doesn't exist"
		exit 1
	fi

	$DIFF -Nurd $SRCD $DSTD
}

doclean() {
	[ $# -eq 0 ] && usage
	[ $# -gt 1 ] && usage

	if [ "x$1" = "xall" ]; then
		rm -rf $TMPD/*
	else
		CMT="`git rev-parse --short $1`"

		if [ -d "$TMPD/$CMT" ]; then
			rm -rf $TMPD/$CMT
		else
			echo >&2 "$CMT not found"
		fi
	fi
}

[ $# -eq 0 ] &&	usage

case "$1" in
	record)
		shift
		dorecord $*
		;;
	diff)
		shift
		dodiff $*
		;;
	clean)
		shift
		doclean $*
		;;
	*)
		echo >&2 "Unrecognized command '$1'"
		exit 1
		;;
esac