File : a-sytaco-xi.ads
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 -- S p e c --
8 -- --
9 -- Copyright (C) 1992-2016, Free Software Foundation, Inc. --
10 -- --
11 -- This specification is derived from the Ada Reference Manual for use with --
12 -- GNAT. The copyright notice above, and the license provisions that follow --
13 -- apply solely to the contents of the part following the private keyword. --
14 -- --
15 -- GNAT is free software; you can redistribute it and/or modify it under --
16 -- terms of the GNU General Public License as published by the Free Soft- --
17 -- ware Foundation; either version 3, or (at your option) any later ver- --
18 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
19 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
20 -- or FITNESS FOR A PARTICULAR PURPOSE. --
21 -- --
22 -- --
23 -- --
24 -- --
25 -- --
26 -- You should have received a copy of the GNU General Public License and --
27 -- a copy of the GCC Runtime Library Exception along with this program; --
28 -- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see --
29 -- <http://www.gnu.org/licenses/>. --
30 -- --
31 -- GNAT was originally developed by the GNAT team at New York University. --
32 -- Extensive contributions were provided by Ada Core Technologies Inc. --
33 -- --
34 ------------------------------------------------------------------------------
35
36 -- This is the generic bare board version of this package
37
38 with System.Tasking;
39
40 with Ada.Task_Identification;
41
42 package Ada.Synchronous_Task_Control with
43 SPARK_Mode
44 is
45 pragma Preelaborate;
46 -- In accordance with Ada 2005 AI-362
47
48 type Suspension_Object is limited private;
49 -- There was a 'Default_Initial_Condition' but it is removed as it resulted
50 -- in an undefined symbol.
51
52 procedure Set_True (S : in out Suspension_Object) with
53 Global => null,
54 Depends => (S => null,
55 null => S);
56
57 procedure Set_False (S : in out Suspension_Object) with
58 Global => null,
59 Depends => (S => null,
60 null => S);
61
62 function Current_State (S : Suspension_Object) return Boolean with
63 Volatile_Function,
64 Global => Ada.Task_Identification.Tasking_State;
65
66 procedure Suspend_Until_True (S : in out Suspension_Object) with
67 Global => null,
68 Depends => (S => null,
69 null => S);
70
71 private
72 pragma SPARK_Mode (Off);
73
74 -- Using a protected object may seem overkill, but assuming the
75 -- appropriate restrictions (such as those imposed by the Ravenscar
76 -- profile) protected operations are very efficient. Moreover, this
77 -- allows for a generic implementation that is not dependent on the
78 -- underlying operating system.
79
80 protected type Suspension_Object is
81 entry Wait;
82 procedure Set_False;
83 procedure Set_True;
84 function Get_Open return Boolean;
85
86 pragma Interrupt_Priority;
87 private
88 Open : Boolean := False;
89 -- Status
90 end Suspension_Object;
91
92 end Ada.Synchronous_Task_Control;