gcc/ada/a-sytaco.adb

   1 ------------------------------------------------------------------------------
   2 --                                                                          --
   3 --                         GNAT RUN-TIME COMPONENTS                         --
   4 --                                                                          --
   5 --         A D A . S Y N C H R O N O U S _ T A S K _ C O N T R O L          --
   6 --                                                                          --
   7 --                                 B o d y                                  --
   8 --                                                                          --
   9 --          Copyright (C) 1992-2009, 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 -- 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 with Ada.Exceptions;
  33
  34 with System.Tasking;
  35 with System.Task_Primitives.Operations;
  36
  37 package body Ada.Synchronous_Task_Control is
  38
  39    ----------------
  40    -- Initialize --
  41    ----------------
  42
  43    procedure Initialize (S : in out Suspension_Object) is
  44    begin
  45       System.Task_Primitives.Operations.Initialize (S.SO);
  46    end Initialize;
  47
  48    --------------
  49    -- Finalize --
  50    --------------
  51
  52    procedure Finalize (S : in out Suspension_Object) is
  53    begin
  54       System.Task_Primitives.Operations.Finalize (S.SO);
  55    end Finalize;
  56
  57    -------------------
  58    -- Current_State --
  59    -------------------
  60
  61    function Current_State (S : Suspension_Object) return Boolean is
  62    begin
  63       return System.Task_Primitives.Operations.Current_State (S.SO);
  64    end Current_State;
  65
  66    ---------------
  67    -- Set_False --
  68    ---------------
  69
  70    procedure Set_False (S : in out Suspension_Object) is
  71    begin
  72       System.Task_Primitives.Operations.Set_False (S.SO);
  73    end Set_False;
  74
  75    --------------
  76    -- Set_True --
  77    --------------
  78
  79    procedure Set_True (S : in out Suspension_Object) is
  80    begin
  81       System.Task_Primitives.Operations.Set_True (S.SO);
  82    end Set_True;
  83
  84    ------------------------
  85    -- Suspend_Until_True --
  86    ------------------------
  87
  88    procedure Suspend_Until_True (S : in out Suspension_Object) is
  89    begin
  90       --  This is a potentially blocking (see ARM D.10, par. 10), so that
  91       --  if pragma Detect_Blocking is active then Program_Error must be
  92       --  raised if this operation is called from a protected action.
  93
  94       if System.Tasking.Detect_Blocking
  95         and then System.Tasking.Self.Common.Protected_Action_Nesting > 0
  96       then
  97          Ada.Exceptions.Raise_Exception
  98            (Program_Error'Identity, "potentially blocking operation");
  99       end if;
 100
 101       System.Task_Primitives.Operations.Suspend_Until_True (S.SO);
 102    end Suspend_Until_True;
 103
 104 end Ada.Synchronous_Task_Control;