gcc/ada/s-tasinf-mingw.adb

   1 ------------------------------------------------------------------------------
   2 --                                                                          --
   3 --                         GNAT COMPILER COMPONENTS                         --
   4 --                                                                          --
   5 --                     S Y S T E M . T A S K _ I N F O                      --
   6 --                                                                          --
   7 --                                 B o d y                                  --
   8 --                                                                          --
   9 --         Copyright (C) 2007-2008, Free Software Foundation, Inc.          --
  10 --                                                                          --
  11 -- GNAT is free software;  you can  redistribute it  and/or modify it under --
  12 -- terms of the  GNU General Public License as published  by the Free Soft- --
  13 -- ware  Foundation;  either version 2,  or (at your option) any later ver- --
  14 -- sion.  GNAT is distributed in the hope that it will be useful, but WITH- --
  15 -- OUT ANY WARRANTY;  without even the  implied warranty of MERCHANTABILITY --
  16 -- or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License --
  17 -- for  more details.  You should have  received  a copy of the GNU General --
  18 -- Public License  distributed with GNAT;  see file COPYING.  If not, write --
  19 -- to  the  Free Software Foundation,  51  Franklin  Street,  Fifth  Floor, --
  20 -- Boston, MA 02110-1301, USA.                                              --
  21 --                                                                          --
  22 -- As a special exception,  if other files  instantiate  generics from this --
  23 -- unit, or you link  this unit with other files  to produce an executable, --
  24 -- this  unit  does not  by itself cause  the resulting  executable  to  be --
  25 -- covered  by the  GNU  General  Public  License.  This exception does not --
  26 -- however invalidate  any other reasons why  the executable file  might be --
  27 -- covered by the  GNU Public License.                                      --
  28 --                                                                          --
  29 -- GNAT was originally developed  by the GNAT team at  New York University. --
  30 -- Extensive contributions were provided by Ada Core Technologies Inc.      --
  31 --                                                                          --
  32 ------------------------------------------------------------------------------
  33
  34 --  This is the Windows (native) version of this module
  35
  36 with System.OS_Interface;
  37 pragma Unreferenced (System.OS_Interface);
  38 --  System.OS_Interface is not used today, but the protocol between the
  39 --  run-time and the binder is that any tasking application uses
  40 --  System.OS_Interface, so notify the binder with this "with" clause.
  41
  42 package body System.Task_Info is
  43
  44    N_CPU : Natural := 0;
  45    pragma Atomic (N_CPU);
  46    --  Cache CPU number. Use pragma Atomic to avoid a race condition when
  47    --  setting N_CPU in Number_Of_Processors below.
  48
  49    --------------------------
  50    -- Number_Of_Processors --
  51    --------------------------
  52
  53    function Number_Of_Processors return Positive is
  54    begin
  55       if N_CPU = 0 then
  56          declare
  57             SI : aliased Win32.SYSTEM_INFO;
  58          begin
  59             Win32.GetSystemInfo (SI'Access);
  60             N_CPU := Positive (SI.dwNumberOfProcessors);
  61          end;
  62       end if;
  63
  64       return N_CPU;
  65    end Number_Of_Processors;
  66
  67 end System.Task_Info;