gcc/mkmap-symver.awk

   1 # Generate an ELF symbol version map a-la Solaris and GNU ld.
   2 #       Copyright (C) 2007  Free Software Foundation, Inc.
   3 #       Contributed by Richard Henderson <rth@cygnus.com>
   4 #
   5 # This file is part of GCC.
   6 #
   7 # GCC is free software; you can redistribute it and/or modify it under
   8 # the terms of the GNU General Public License as published by the Free
   9 # Software Foundation; either version 3, or (at your option) any later
  10 # version.
  11 #
  12 # GCC is distributed in the hope that it will be useful, but WITHOUT
  13 # ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  14 # or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public
  15 # License for more details.
  16 #
  17 # You should have received a copy of the GNU General Public License
  18 # along with GCC; see the file COPYING3.  If not see
  19 # <http://www.gnu.org/licenses/>.
  20
  21 BEGIN {
  22   state = "nm";
  23   sawsymbol = 0;
  24   if (leading_underscore)
  25     prefix = "_";
  26   else
  27     prefix = "";
  28 }
  29
  30 # Remove comment and blank lines.
  31 /^ *#/ || /^ *$/ {
  32   next;
  33 }
  34
  35 # We begin with nm input.  Collect the set of symbols that are present
  36 # so that we can not emit them into the final version script -- Solaris
  37 # complains at us if we do.
  38
  39 state == "nm" && /^%%/ {
  40   state = "ver";
  41   next;
  42 }
  43
  44 state == "nm" && ($1 == "U" || $2 == "U") {
  45   next;
  46 }
  47
  48 state == "nm" && NF == 3 {
  49   def[$3] = 1;
  50   sawsymbol = 1;
  51   next;
  52 }
  53
  54 state == "nm" {
  55   next;
  56 }
  57
  58 # Now we process a simplified variant of the Solaris symbol version
  59 # script.  We have one symbol per line, no semicolons, simple markers
  60 # for beginning and ending each section, and %inherit markers for
  61 # describing version inheritence.  A symbol may appear in more than
  62 # one symbol version, and the last seen takes effect.
  63 # The magic version name '%exclude' causes all the symbols given that
  64 # version to be dropped from the output (unless a later version overrides).
  65
  66 NF == 3 && $1 == "%inherit" {
  67   inherit[$2] = $3;
  68   next;
  69 }
  70
  71 NF == 2 && $2 == "{" {
  72   if ($1 != "%exclude")
  73     libs[$1] = 1;
  74   thislib = $1;
  75   next;
  76 }
  77
  78 $1 == "}" {
  79   thislib = "";
  80   next;
  81 }
  82
  83 {
  84   sym = prefix $1;
  85   if (thislib != "%exclude")
  86     ver[sym] = thislib;
  87   else
  88     delete ver[sym];
  89   next;
  90 }
  91
  92 END {
  93   if (!sawsymbol)
  94     {
  95       print "No symbols seen -- broken or mis-installed nm?" | "cat 1>&2";
  96       exit 1;
  97     }
  98   for (l in libs)
  99     output(l);
 100 }
 101
 102 function output(lib) {
 103   if (done[lib])
 104     return;
 105   done[lib] = 1;
 106   if (inherit[lib])
 107     output(inherit[lib]);
 108
 109   empty=1
 110   for (sym in ver)
 111     if ((ver[sym] == lib) && (sym in def))
 112       {
 113         if (empty)
 114           {
 115             printf("%s {\n", lib);
 116             printf("  global:\n");
 117             empty = 0;
 118           }
 119         printf("\t%s;\n", sym);
 120       }
 121
 122   if (empty)
 123     {
 124       for (l in libs)
 125         if (inherit[l] == lib)
 126           inherit[l] = inherit[lib];
 127     }
 128   else if (inherit[lib])
 129     printf("} %s;\n", inherit[lib]);
 130   else
 131     printf ("\n  local:\n\t*;\n};\n");
 132 }