gcc/ada/gnatvsn.adb

   1 ------------------------------------------------------------------------------
   2 --                                                                          --
   3 --                         GNAT COMPILER COMPONENTS                         --
   4 --                                                                          --
   5 --                              G N A T V S N                               --
   6 --                                                                          --
   7 --                                 B o d y                                  --
   8 --                                                                          --
   9 --                                                                          --
  10 --          Copyright (C) 2002 Free Software Foundation, Inc.               --
  11 --                                                                          --
  12 -- GNAT is free software;  you can  redistribute it  and/or modify it under --
  13 -- terms of the  GNU General Public License as published  by the Free Soft- --
  14 -- ware  Foundation;  either version 2,  or (at your option) any later ver- --
  15 -- sion.  GNAT is distributed in the hope that it will be useful, but WITH- --
  16 -- OUT ANY WARRANTY;  without even the  implied warranty of MERCHANTABILITY --
  17 -- or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License --
  18 -- for  more details.  You should have  received  a copy of the GNU General --
  19 -- Public License  distributed with GNAT;  see file COPYING.  If not, write --
  20 -- to  the Free Software Foundation,  59 Temple Place - Suite 330,  Boston, --
  21 -- MA 02111-1307, USA.                                                      --
  22 --                                                                          --
  23 -- As a special exception,  if other files  instantiate  generics from this --
  24 -- unit, or you link  this unit with other files  to produce an executable, --
  25 -- this  unit  does not  by itself cause  the resulting  executable  to  be --
  26 -- covered  by the  GNU  General  Public  License.  This exception does not --
  27 -- however invalidate  any other reasons why  the executable file  might be --
  28 -- covered by the  GNU Public License.                                      --
  29 --                                                                          --
  30 -- GNAT was originally developed  by the GNAT team at  New York University. --
  31 -- It is now maintained by Ada Core Technologies Inc (http://www.gnat.com). --
  32 --                                                                          --
  33 ------------------------------------------------------------------------------
  34
  35 package body Gnatvsn is
  36
  37    --  Import the string constant defined in the (language-independent)
  38    --  source file version.c.
  39
  40    --  The size is a lie; we have no way of writing the truth (the size
  41    --  is variable and depends on the actual text of the constant).
  42
  43    --  FIXME: It should be possible to declare this to be a constant, but
  44    --  that is rejected by the compiler ("invalid context for deferred
  45    --  constant declaration").  Per Ada95 this constraint only applies to
  46    --  deferred constants completed by a full constant declaration, not
  47    --  deferred constants completed by a pragma Import.
  48
  49    Version_String : array (0 .. Ver_Len_Max) of aliased Character;
  50    pragma Import (C, Version_String, "version_string");
  51
  52    --  Convert that string constant to an Ada String and return it.
  53    --  This is essentially the same as the To_Ada routine in
  54    --  Interfaces.C; that package is not linked into gnat1 so
  55    --  we cannot use it.
  56
  57    function Gnat_Version_String return String
  58    is
  59       Count : Natural := 0;
  60
  61    begin
  62       loop
  63          if Version_String (Count) = Character'First then
  64             exit;
  65          else
  66             Count := Count + 1;
  67          end if;
  68       end loop;
  69
  70       declare
  71          R : String (1 .. Count);
  72
  73       begin
  74          for J in R'Range loop
  75             R (J) := Version_String (J - 1);
  76          end loop;
  77
  78          return R;
  79       end;
  80    end Gnat_Version_String;
  81
  82 end Gnatvsn;