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 --                                 S p e c                                  --
   8 --                                                                          --
   9 --            Copyright (C) 2007, 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 package body System.Task_Info is
  37
  38    N_CPU : Natural := 0;
  39    pragma Atomic (N_CPU);
  40    --  Cache CPU number. Use pragma Atomic to avoid a race condition when
  41    --  setting N_CPU in Number_Of_Processors below.
  42
  43    --------------------------
  44    -- Number_Of_Processors --
  45    --------------------------
  46
  47    function Number_Of_Processors return Positive is
  48    begin
  49       if N_CPU = 0 then
  50          declare
  51             SI : aliased System.OS_Interface.SYSTEM_INFO;
  52          begin
  53             System.OS_Interface.GetSystemInfo (SI'Access);
  54             N_CPU := Positive (SI.dwNumberOfProcessors);
  55          end;
  56       end if;
  57
  58       return N_CPU;
  59    end Number_Of_Processors;
  60
  61 end System.Task_Info;