gcc/ada/libgnat/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) 1999-2018, 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 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 -- As a special exception under Section 7 of GPL version 3, you are granted --
  19 -- additional permissions described in the GCC Runtime Library Exception,   --
  20 -- version 3.1, as published by the Free Software Foundation.               --
  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 implementation is specific to NT
  33
  34 with System.OS_Interface;
  35 with System.Task_Lock;
  36 with System.Win32;
  37
  38 with Interfaces.C.Strings;
  39
  40 package body System.Global_Locks is
  41
  42    package TSL renames System.Task_Lock;
  43    package OSI renames System.OS_Interface;
  44    package ICS renames Interfaces.C.Strings;
  45
  46    subtype Lock_File_Entry is Win32.HANDLE;
  47
  48    Last_Lock  : Lock_Type := Null_Lock;
  49    Lock_Table : array (Lock_Type range 1 .. 15) of Lock_File_Entry;
  50
  51    -----------------
  52    -- Create_Lock --
  53    -----------------
  54
  55    procedure Create_Lock (Lock : out Lock_Type; Name : String) is
  56       L : Lock_Type;
  57
  58    begin
  59       TSL.Lock;
  60       Last_Lock := Last_Lock + 1;
  61       L := Last_Lock;
  62       TSL.Unlock;
  63
  64       if L > Lock_Table'Last then
  65          raise Lock_Error;
  66       end if;
  67
  68       Lock_Table (L) :=
  69         OSI.CreateMutex (null, Win32.FALSE, ICS.New_String (Name));
  70       Lock := L;
  71    end Create_Lock;
  72
  73    ------------------
  74    -- Acquire_Lock --
  75    ------------------
  76
  77    procedure Acquire_Lock (Lock : in out Lock_Type) is
  78       use type Win32.DWORD;
  79
  80       Res : Win32.DWORD;
  81
  82    begin
  83       Res := OSI.WaitForSingleObject (Lock_Table (Lock), OSI.Wait_Infinite);
  84
  85       if Res = OSI.WAIT_FAILED then
  86          raise Lock_Error;
  87       end if;
  88    end Acquire_Lock;
  89
  90    ------------------
  91    -- Release_Lock --
  92    ------------------
  93
  94    procedure Release_Lock (Lock : in out Lock_Type) is
  95       use type Win32.BOOL;
  96
  97       Res : Win32.BOOL;
  98
  99    begin
 100       Res := OSI.ReleaseMutex (Lock_Table (Lock));
 101
 102       if Res = Win32.FALSE then
 103          raise Lock_Error;
 104       end if;
 105    end Release_Lock;
 106
 107 end System.Global_Locks;