elf/ldd.bash.in

   1 #!/bin/bash
   2 # Copyright (C) 1996-2021 Free Software Foundation, Inc.
   3 # This file is part of the GNU C Library.
   4
   5 # The GNU C Library is free software; you can redistribute it and/or
   6 # modify it under the terms of the GNU Lesser General Public
   7 # License as published by the Free Software Foundation; either
   8 # version 2.1 of the License, or (at your option) any later version.
   9
  10 # The GNU C Library is distributed in the hope that it will be useful,
  11 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13 # Lesser General Public License for more details.
  14
  15 # You should have received a copy of the GNU Lesser General Public
  16 # License along with the GNU C Library; if not, see
  17 # <https://www.gnu.org/licenses/>.
  18
  19
  20 # This is the `ldd' command, which lists what shared libraries are
  21 # used by given dynamically-linked executables.  It works by invoking the
  22 # run-time dynamic linker as a command and setting the environment
  23 # variable LD_TRACE_LOADED_OBJECTS to a non-empty value.
  24
  25 # We should be able to find the translation right at the beginning.
  26 TEXTDOMAIN=libc
  27 TEXTDOMAINDIR=@TEXTDOMAINDIR@
  28
  29 RTLDLIST=@RTLD@
  30 warn=
  31 bind_now=
  32 verbose=
  33
  34 while test $# -gt 0; do
  35   case "$1" in
  36   --vers | --versi | --versio | --version)
  37     echo 'ldd @PKGVERSION@@VERSION@'
  38     printf $"Copyright (C) %s Free Software Foundation, Inc.
  39 This is free software; see the source for copying conditions.  There is NO
  40 warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  41 " "2021"
  42     printf $"Written by %s and %s.
  43 " "Roland McGrath" "Ulrich Drepper"
  44     exit 0
  45     ;;
  46   --h | --he | --hel | --help)
  47     echo $"Usage: ldd [OPTION]... FILE...
  48       --help              print this help and exit
  49       --version           print version information and exit
  50   -d, --data-relocs       process data relocations
  51   -r, --function-relocs   process data and function relocations
  52   -u, --unused            print unused direct dependencies
  53   -v, --verbose           print all information
  54 "
  55     printf $"For bug reporting instructions, please see:\\n%s.\\n" \
  56       "@REPORT_BUGS_TO@"
  57     exit 0
  58     ;;
  59   -d | --d | --da | --dat | --data | --data- | --data-r | --data-re | \
  60   --data-rel | --data-relo | --data-reloc | --data-relocs)
  61     warn=yes
  62     shift
  63     ;;
  64   -r | --f | --fu | --fun | --func | --funct | --functi | --functio | \
  65   --function | --function- | --function-r | --function-re | --function-rel | \
  66   --function-relo | --function-reloc | --function-relocs)
  67     warn=yes
  68     bind_now=yes
  69     shift
  70     ;;
  71   -v | --verb | --verbo | --verbos | --verbose)
  72     verbose=yes
  73     shift
  74     ;;
  75   -u | --u | --un | --unu | --unus | --unuse | --unused)
  76     unused=yes
  77     shift
  78     ;;
  79   --v | --ve | --ver)
  80     echo >&2 $"ldd: option \`$1' is ambiguous"
  81     exit 1
  82     ;;
  83   --)           # Stop option processing.
  84     shift; break
  85     ;;
  86   -*)
  87     echo >&2 'ldd:' $"unrecognized option" "\`$1'"
  88     echo >&2 $"Try \`ldd --help' for more information."
  89     exit 1
  90     ;;
  91   *)
  92     break
  93     ;;
  94   esac
  95 done
  96
  97 nonelf ()
  98 {
  99   # Maybe extra code for non-ELF binaries.
 100   return 1;
 101 }
 102
 103 add_env="LD_TRACE_LOADED_OBJECTS=1 LD_WARN=$warn LD_BIND_NOW=$bind_now"
 104 add_env="$add_env LD_VERBOSE=$verbose"
 105 if test "$unused" = yes; then
 106   add_env="$add_env LD_DEBUG=\"$LD_DEBUG${LD_DEBUG:+,}unused\""
 107 fi
 108
 109 # The following command substitution is needed to make ldd work in SELinux
 110 # environments where the RTLD might not have permission to write to the
 111 # terminal.  The extra "x" character prevents the shell from trimming trailing
 112 # newlines from command substitution results.  This function is defined as a
 113 # subshell compound list (using "(...)") to prevent parameter assignments from
 114 # affecting the calling shell execution environment.
 115 try_trace() (
 116   output=$(eval $add_env '"$@"' 2>&1; rc=$?; printf 'x'; exit $rc)
 117   rc=$?
 118   printf '%s' "${output%x}"
 119   return $rc
 120 )
 121
 122 case $# in
 123 0)
 124   echo >&2 'ldd:' $"missing file arguments"
 125   echo >&2 $"Try \`ldd --help' for more information."
 126   exit 1
 127   ;;
 128 1)
 129   single_file=t
 130   ;;
 131 *)
 132   single_file=f
 133   ;;
 134 esac
 135
 136 result=0
 137 for file do
 138   # We don't list the file name when there is only one.
 139   test $single_file = t || echo "${file}:"
 140   case $file in
 141   */*) :
 142        ;;
 143   *) file=./$file
 144      ;;
 145   esac
 146   if test ! -e "$file"; then
 147     echo "ldd: ${file}:" $"No such file or directory" >&2
 148     result=1
 149   elif test ! -f "$file"; then
 150     echo "ldd: ${file}:" $"not regular file" >&2
 151     result=1
 152   elif test -r "$file"; then
 153     test -x "$file" || echo 'ldd:' $"\
 154 warning: you do not have execution permission for" "\`$file'" >&2
 155     RTLD=
 156     ret=1
 157     for rtld in ${RTLDLIST}; do
 158       if test -x $rtld; then
 159         verify_out=`${rtld} --verify "$file"`
 160         ret=$?
 161         case $ret in
 162         [02]) RTLD=${rtld}; break;;
 163         esac
 164       fi
 165     done
 166     case $ret in
 167     1)
 168       # This can be a non-ELF binary or no binary at all.
 169       nonelf "$file" || {
 170         echo $" not a dynamic executable" >&2
 171         result=1
 172       }
 173       ;;
 174     0|2)
 175       try_trace "$RTLD" "$file" || result=1
 176       ;;
 177     *)
 178       echo 'ldd:' ${RTLD} $"exited with unknown exit code" "($ret)" >&2
 179       exit 1
 180       ;;
 181     esac
 182   else
 183     echo 'ldd:' $"error: you do not have read permission for" "\`$file'" >&2
 184     result=1
 185   fi
 186 done
 187
 188 exit $result
 189 # Local Variables:
 190 #  mode:ksh
 191 # End: