1#! /bin/sh 2 3# Add a .gdb_index section to a file. 4 5# Copyright (C) 2010-2023 Free Software Foundation, Inc. 6# This program is free software; you can redistribute it and/or modify 7# it under the terms of the GNU General Public License as published by 8# the Free Software Foundation; either version 3 of the License, or 9# (at your option) any later version. 10# 11# This program is distributed in the hope that it will be useful, 12# but WITHOUT ANY WARRANTY; without even the implied warranty of 13# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14# GNU General Public License for more details. 15# 16# You should have received a copy of the GNU General Public License 17# along with this program. If not, see <http://www.gnu.org/licenses/>. 18 19# This program assumes gdb and objcopy are in $PATH. 20# If not, or you want others, pass the following in the environment 21GDB=${GDB:=gdb} 22OBJCOPY=${OBJCOPY:=objcopy} 23READELF=${READELF:=readelf} 24 25myname="${0##*/}" 26 27dwarf5="" 28if [ "$1" = "-dwarf-5" ]; then 29 dwarf5="$1" 30 shift 31fi 32 33if test $# != 1; then 34 echo "usage: $myname [-dwarf-5] FILE" 1>&2 35 exit 1 36fi 37 38file="$1" 39 40if test -L "$file"; then 41 if ! command -v readlink >/dev/null 2>&1; then 42 echo "$myname: 'readlink' missing. Failed to follow symlink $1." 1>&2 43 exit 1 44 fi 45 46 # Count number of links followed in order to detect loops. 47 count=0 48 while test -L "$file"; do 49 target=$(readlink "$file") 50 51 case "$target" in 52 /*) 53 file="$target" 54 ;; 55 *) 56 file="$(dirname "$file")/$target" 57 ;; 58 esac 59 60 count="$((count + 1))" 61 if test "$count" -gt 10; then 62 echo "$myname: Detected loop while following link $file" 63 exit 1 64 fi 65 done 66fi 67 68if test ! -r "$file"; then 69 echo "$myname: unable to access: $file" 1>&2 70 exit 1 71fi 72 73dir="${file%/*}" 74test "$dir" = "$file" && dir="." 75 76dwz_file="" 77if $READELF -S "$file" | grep -q " \.gnu_debugaltlink "; then 78 dwz_file=$($READELF --string-dump=.gnu_debugaltlink "$file" \ 79 | grep -A1 "'\.gnu_debugaltlink':" \ 80 | tail -n +2 \ 81 | sed 's/.*]//') 82 dwz_file=$(echo $dwz_file) 83 if $READELF -S "$dwz_file" | grep -E -q " \.(gdb_index|debug_names) "; then 84 # Already has an index, skip it. 85 dwz_file="" 86 fi 87fi 88 89set_files () 90{ 91 fpath="$1" 92 93 index4="${fpath}.gdb-index" 94 index5="${fpath}.debug_names" 95 debugstr="${fpath}.debug_str" 96 debugstrmerge="${fpath}.debug_str.merge" 97 debugstrerr="${fpath}.debug_str.err" 98} 99 100tmp_files= 101for f in "$file" "$dwz_file"; do 102 if [ "$f" = "" ]; then 103 continue 104 fi 105 set_files "$f" 106 tmp_files="$tmp_files $index4 $index5 $debugstr $debugstrmerge $debugstrerr" 107done 108 109rm -f $tmp_files 110 111# Ensure intermediate index file is removed when we exit. 112trap "rm -f $tmp_files" 0 113 114$GDB --batch -nx -iex 'set auto-load no' \ 115 -iex 'set debuginfod enabled off' \ 116 -ex "file $file" -ex "save gdb-index $dwarf5 $dir" || { 117 # Just in case. 118 status=$? 119 echo "$myname: gdb error generating index for $file" 1>&2 120 exit $status 121} 122 123# In some situations gdb can exit without creating an index. This is 124# not an error. 125# E.g., if $file is stripped. This behaviour is akin to stripping an 126# already stripped binary, it's a no-op. 127status=0 128 129handle_file () 130{ 131 fpath="$1" 132 133 set_files "$fpath" 134 135 if test -f "$index4" -a -f "$index5"; then 136 echo "$myname: Both index types were created for $fpath" 1>&2 137 status=1 138 elif test -f "$index4" -o -f "$index5"; then 139 if test -f "$index4"; then 140 index="$index4" 141 section=".gdb_index" 142 else 143 index="$index5" 144 section=".debug_names" 145 fi 146 debugstradd=false 147 debugstrupdate=false 148 if test -s "$debugstr"; then 149 if ! $OBJCOPY --dump-section .debug_str="$debugstrmerge" "$fpath" \ 150 /dev/null 2>$debugstrerr; then 151 cat >&2 $debugstrerr 152 exit 1 153 fi 154 if grep -q "can't dump section '.debug_str' - it does not exist" \ 155 $debugstrerr; then 156 debugstradd=true 157 else 158 debugstrupdate=true 159 cat >&2 $debugstrerr 160 fi 161 cat "$debugstr" >>"$debugstrmerge" 162 fi 163 164 $OBJCOPY --add-section $section="$index" \ 165 --set-section-flags $section=readonly \ 166 $(if $debugstradd; then \ 167 echo --add-section .debug_str="$debugstrmerge"; \ 168 echo --set-section-flags .debug_str=readonly; \ 169 fi; \ 170 if $debugstrupdate; then \ 171 echo --update-section .debug_str="$debugstrmerge"; \ 172 fi) \ 173 "$fpath" "$fpath" 174 175 status=$? 176 else 177 echo "$myname: No index was created for $fpath" 1>&2 178 echo "$myname: [Was there no debuginfo? Was there already an index?]" \ 179 1>&2 180 fi 181} 182 183handle_file "$file" 184if [ "$dwz_file" != "" ]; then 185 handle_file "$dwz_file" 186fi 187 188exit $status 189