LXR linux/scripts/objdiff

   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
  28SRCTREE=$(cd $(git rev-parse --show-toplevel 2>/dev/null); pwd)
  29
  30if [ -z "$SRCTREE" ]; then
  31        echo >&2 "ERROR: Not a git repository."
  32        exit 1
  33fi
  34
  35TMPD=$SRCTREE/.tmp_objdiff
  36
  37usage() {
  38        echo >&2 "Usage: $0 <command> <args>"
  39        echo >&2 "  record    <list of object files or directories>"
  40        echo >&2 "  diff      <commitA> <commitB>"
  41        echo >&2 "  clean     all | <commit>"
  42        exit 1
  43}
  44
  45get_output_dir() {
  46        dir=${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
  57do_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
  69dorecord() {
  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
  90dodiff() {
  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
 123doclean() {
 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
 142case "$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                ;;
 159esac
 160