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) 1992-2019, 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
32with Ada.Exceptions;
33
34with System.Tasking;
35with System.Task_Primitives.Operations;
36
37package body Ada.Synchronous_Task_Control with
38  SPARK_Mode => Off
39is
40
41   ----------------
42   -- Initialize --
43   ----------------
44
45   procedure Initialize (S : in out Suspension_Object) is
46   begin
47      System.Task_Primitives.Operations.Initialize (S.SO);
48   end Initialize;
49
50   --------------
51   -- Finalize --
52   --------------
53
54   procedure Finalize (S : in out Suspension_Object) is
55   begin
56      System.Task_Primitives.Operations.Finalize (S.SO);
57   end Finalize;
58
59   -------------------
60   -- Current_State --
61   -------------------
62
63   function Current_State (S : Suspension_Object) return Boolean is
64   begin
65      return System.Task_Primitives.Operations.Current_State (S.SO);
66   end Current_State;
67
68   ---------------
69   -- Set_False --
70   ---------------
71
72   procedure Set_False (S : in out Suspension_Object) is
73   begin
74      System.Task_Primitives.Operations.Set_False (S.SO);
75   end Set_False;
76
77   --------------
78   -- Set_True --
79   --------------
80
81   procedure Set_True (S : in out Suspension_Object) is
82   begin
83      System.Task_Primitives.Operations.Set_True (S.SO);
84   end Set_True;
85
86   ------------------------
87   -- Suspend_Until_True --
88   ------------------------
89
90   procedure Suspend_Until_True (S : in out Suspension_Object) is
91   begin
92      --  This is a potentially blocking (see ARM D.10, par. 10), so that
93      --  if pragma Detect_Blocking is active then Program_Error must be
94      --  raised if this operation is called from a protected action.
95
96      if System.Tasking.Detect_Blocking
97        and then System.Tasking.Self.Common.Protected_Action_Nesting > 0
98      then
99         Ada.Exceptions.Raise_Exception
100           (Program_Error'Identity, "potentially blocking operation");
101      end if;
102
103      System.Task_Primitives.Operations.Suspend_Until_True (S.SO);
104   end Suspend_Until_True;
105
106end Ada.Synchronous_Task_Control;
107