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) 1999-2001 Ada Core Technologies, 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,  59 Temple Place - Suite 330,  Boston, --
  20 -- MA 02111-1307, 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 GNAT.Task_Lock;
  37
  38 with Interfaces.C.Strings;
  39 with System.OS_Interface;
  40
  41 package body System.Global_Locks is
  42
  43    package TSL renames GNAT.Task_Lock;
  44    package OSI renames System.OS_Interface;
  45    package ICS renames Interfaces.C.Strings;
  46
  47    subtype Lock_File_Entry is OSI.HANDLE;
  48
  49    Last_Lock  : Lock_Type := Null_Lock;
  50    Lock_Table : array (Lock_Type range 1 .. 15) of Lock_File_Entry;
  51
  52    -----------------
  53    -- Create_Lock --
  54    -----------------
  55
  56    procedure Create_Lock
  57      (Lock : out Lock_Type;
  58       Name : in String)
  59    is
  60       L : Lock_Type;
  61
  62    begin
  63       TSL.Lock;
  64       Last_Lock := Last_Lock + 1;
  65       L := Last_Lock;
  66       TSL.Unlock;
  67
  68       if L > Lock_Table'Last then
  69          raise Lock_Error;
  70       end if;
  71
  72       Lock_Table (L) :=
  73         OSI.CreateMutex (null, OSI.BOOL (False), ICS.New_String (Name));
  74       Lock := L;
  75    end Create_Lock;
  76
  77    ------------------
  78    -- Acquire_Lock --
  79    ------------------
  80
  81    procedure Acquire_Lock
  82      (Lock : in out Lock_Type)
  83    is
  84       use type OSI.DWORD;
  85
  86       Res : OSI.DWORD;
  87    begin
  88       Res := OSI.WaitForSingleObject (Lock_Table (Lock), OSI.Wait_Infinite);
  89
  90       if Res = OSI.WAIT_FAILED then
  91          raise Lock_Error;
  92       end if;
  93    end Acquire_Lock;
  94
  95    ------------------
  96    -- Release_Lock --
  97    ------------------
  98
  99    procedure Release_Lock
 100      (Lock : in out Lock_Type)
 101    is
 102       use type OSI.BOOL;
 103
 104       Res : OSI.BOOL;
 105    begin
 106       Res := OSI.ReleaseMutex (Lock_Table (Lock));
 107
 108       if Res = OSI.False then
 109          raise Lock_Error;
 110       end if;
 111    end Release_Lock;
 112
 113 end System.Global_Locks;