File : 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) 2007-2009, 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 3, 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. --
17 -- --
18 -- --
19 -- --
20 -- --
21 -- --
22 -- You should have received a copy of the GNU General Public License and --
23 -- a copy of the GCC Runtime Library Exception along with this program; --
24 -- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see --
25 -- <http://www.gnu.org/licenses/>. --
26 -- --
27 -- GNAT was originally developed by the GNAT team at New York University. --
28 -- Extensive contributions were provided by Ada Core Technologies Inc. --
29 -- --
30 ------------------------------------------------------------------------------
31
32 -- This is the Windows (native) version of this module
33
34 with System.OS_Interface;
35 pragma Unreferenced (System.OS_Interface);
36 -- System.OS_Interface is not used today, but the protocol between the
37 -- run-time and the binder is that any tasking application uses
38 -- System.OS_Interface, so notify the binder with this "with" clause.
39
40 package body System.Task_Info is
41
42 N_CPU : Natural := 0;
43 pragma Atomic (N_CPU);
44 -- Cache CPU number. Use pragma Atomic to avoid a race condition when
45 -- setting N_CPU in Number_Of_Processors below.
46
47 --------------------------
48 -- Number_Of_Processors --
49 --------------------------
50
51 function Number_Of_Processors return Positive is
52 begin
53 if N_CPU = 0 then
54 declare
55 SI : aliased Win32.SYSTEM_INFO;
56 begin
57 Win32.GetSystemInfo (SI'Access);
58 N_CPU := Positive (SI.dwNumberOfProcessors);
59 end;
60 end if;
61
62 return N_CPU;
63 end Number_Of_Processors;
64
65 end System.Task_Info;