libstdc++-v3/scripts/extract_symvers.pl

   1 #!/usr/bin/perl -w
   2
   3 # Copyright (C) 2010-2017 Free Software Foundation, Inc.
   4 #
   5 # This file is part of the GNU ISO C++ Library.  This library is free
   6 # software; you can redistribute it and/or modify it under the
   7 # terms of the GNU General Public License as published by the
   8 # Free Software Foundation; either version 3, or (at your option)
   9 # any later version.
  10 #
  11 # This library 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 along
  17 # with this library; see the file COPYING3.  If not see
  18 # <http://www.gnu.org/licenses/>.
  19
  20 # Extract symbol version information on Solaris 2.
  21 #
  22 # Sun ld doesn't record symbol versions in .dynsym entries and they cannot
  23 # easily be extracted from readelf --versions output, so use pvs instead.
  24 # This way, we don't require GNU binutils in the native case.  Also ensures
  25 # that baseline_symbols.txt is identical between native (pvs, elfdump) and
  26 # cross (readelf) cases.
  27
  28 my $lib = shift;
  29
  30 open PVS, "pvs -dsvo $lib |" or die $!;
  31 while (<PVS>) {
  32     chomp;
  33
  34     # Remove trailing semicolon.
  35     s/;$//;
  36
  37     # shared object, dash, version, symbol, [size]
  38     (undef, undef, $version, $symbol, $size) = split;
  39
  40     # Remove colon separator from version field.
  41     $version =~ s/:$//;
  42
  43     # Record base version.  The [BASE] field was only added in Solaris 11,
  44     # so simply use the first record instead.
  45     if ($. == 1) {
  46         $basever = $version;
  47         next;
  48     }
  49
  50     # Skip version declarations.
  51     next unless defined ($symbol);
  52
  53     # Ignore version dependencies.
  54     next if ($symbol =~ /\{.*\}/);
  55
  56     # Emit objects.
  57     if (defined ($size)) {
  58         # Strip parens from object size.
  59         $size =~ s/\((\d+)\)/$1/;
  60
  61         $type{$symbol} = "OBJECT";
  62         $version{$symbol} = $version;
  63         $size{$symbol} = $size;
  64         next;
  65     }
  66
  67     if ($version eq $symbol or $version eq $basever) {
  68         # Emit versions or symbols bound to base versions as objects.
  69         $type{$symbol} = "OBJECT";
  70         if ($version eq $basever) {
  71             $version{$symbol} = $version;
  72         } else {
  73             $version{$symbol} = $symbol;
  74         }
  75         $size{$symbol} = 0;
  76     } else {
  77         # Everything else without a size field is a function.
  78         $type{$symbol} = "FUNC";
  79         $version{$symbol} = $version;
  80     }
  81 }
  82 close PVS or die "pvs error";
  83
  84 # Only look at .dynsym table, like readelf in extract_symvers.
  85 # Ignore error output to avoid getting confused by
  86 # .gnu.version_r: zero sh_entsize information, expected 0x1
  87 # warning with Solaris 11 elfdump on gld-produced shared objects.
  88 open ELFDUMP, "/usr/ccs/bin/elfdump -s -N .dynsym $lib 2>/dev/null |" or die $!;
  89 while (<ELFDUMP>) {
  90     chomp;
  91
  92     # Ignore empty lines.
  93     next if (/^$/);
  94
  95     # Ignore object name header.
  96     next if (/:$/);
  97
  98     # Ignore table header lines.
  99     next if (/^Symbol Table Section:/);
 100     next if (/index.*value.*size/);
 101
 102     # Split table.
 103     (undef, undef, undef, $type, $bind, $oth, undef, $shndx, $name) = split;
 104
 105     # Error out for unknown input.
 106     die "unknown input line:\n$_" unless defined($bind);
 107
 108     # Ignore local symbols.
 109     next if ($bind eq "LOCL");
 110     # Ignore hidden symbols.
 111     next if ($oth eq "H");
 112     # Ignore undefined symbols.
 113     next if ($shndx eq "UNDEF");
 114     # Error out for unhandled cases.   _GLOBAL_OFFSET_TABLE_ is P (protected).
 115     die "unhandled symbol:\n$_" if ($bind !~ /^(GLOB|WEAK)/ or $oth !~ /[DP]/);
 116
 117     # Adapt to readelf type naming convention.
 118     $type = "NOTYPE" if ($type eq "NOTY");
 119     $type = "OBJECT" if ($type eq "OBJT");
 120
 121     # Use correct symbol type.
 122     $type{$name} = $type if ($type{$name} ne $type);
 123 }
 124 close ELFDUMP or die "elfdump error";
 125
 126 foreach $symbol (keys %type) {
 127     if ($type{$symbol} eq "FUNC" || $type{$symbol} eq "NOTYPE") {
 128         push @lines, "$type{$symbol}:$symbol\@\@$version{$symbol}\n";
 129     } elsif ($type{$symbol} eq "OBJECT" and $size{$symbol} == 0) {
 130         # Omit symbols bound to base version; details can differ depending
 131         # on the toolchain used.
 132         next if $version{$symbol} eq $basever;
 133
 134         push @lines, "$type{$symbol}:$size{$symbol}:$version{$symbol}\n";
 135     } else {
 136         push @lines, "$type{$symbol}:$size{$symbol}:$symbol\@\@$version{$symbol}\n";
 137     }
 138 }
 139 print sort @lines;