gcc/ada/s-gloloc-mingw.adb

   1 ------------------------------------------------------------------------------
   2 --                                                                          --
   3 --                         GNAT COMPILER COMPONENTS                         --
   4 --                                                                          --
   5 --                  S Y S T E M . G L O B A L _ L O C K S                   --
   6 --                                                                          --
   7 --                                 B o d y                                  --
   8 --                                                                          --
   9 --                     Copyright (C) 1999-2008, AdaCore                     --
  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 implementation is specific to NT
  35
  36 with System.OS_Interface;
  37 with System.Task_Lock;
  38 with System.Win32;
  39
  40 with Interfaces.C.Strings;
  41
  42 package body System.Global_Locks is
  43
  44    package TSL renames System.Task_Lock;
  45    package OSI renames System.OS_Interface;
  46    package ICS renames Interfaces.C.Strings;
  47
  48    subtype Lock_File_Entry is Win32.HANDLE;
  49
  50    Last_Lock  : Lock_Type := Null_Lock;
  51    Lock_Table : array (Lock_Type range 1 .. 15) of Lock_File_Entry;
  52
  53    -----------------
  54    -- Create_Lock --
  55    -----------------
  56
  57    procedure Create_Lock (Lock : out Lock_Type; Name : String) is
  58       L : Lock_Type;
  59
  60    begin
  61       TSL.Lock;
  62       Last_Lock := Last_Lock + 1;
  63       L := Last_Lock;
  64       TSL.Unlock;
  65
  66       if L > Lock_Table'Last then
  67          raise Lock_Error;
  68       end if;
  69
  70       Lock_Table (L) :=
  71         OSI.CreateMutex (null, Win32.FALSE, ICS.New_String (Name));
  72       Lock := L;
  73    end Create_Lock;
  74
  75    ------------------
  76    -- Acquire_Lock --
  77    ------------------
  78
  79    procedure Acquire_Lock (Lock : in out Lock_Type) is
  80       use type Win32.DWORD;
  81
  82       Res : Win32.DWORD;
  83
  84    begin
  85       Res := OSI.WaitForSingleObject (Lock_Table (Lock), OSI.Wait_Infinite);
  86
  87       if Res = OSI.WAIT_FAILED then
  88          raise Lock_Error;
  89       end if;
  90    end Acquire_Lock;
  91
  92    ------------------
  93    -- Release_Lock --
  94    ------------------
  95
  96    procedure Release_Lock (Lock : in out Lock_Type) is
  97       use type Win32.BOOL;
  98
  99       Res : Win32.BOOL;
 100
 101    begin
 102       Res := OSI.ReleaseMutex (Lock_Table (Lock));
 103
 104       if Res = Win32.FALSE then
 105          raise Lock_Error;
 106       end if;
 107    end Release_Lock;
 108
 109 end System.Global_Locks;