1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
|
------------------------------------------------------------------------------
-- --
-- GNAT RUN-TIME LIBRARY (GNARL) COMPONENTS --
-- --
-- A D A . C A L E N D A R . D E L A Y S --
-- --
-- B o d y --
-- --
-- Copyright (C) 1991-1994, Florida State University --
-- Copyright (C) 1995-2009, AdaCore --
-- --
-- GNARL is free software; you can redistribute it and/or modify it under --
-- terms of the GNU General Public License as published by the Free Soft- --
-- ware Foundation; either version 2, or (at your option) any later ver- --
-- sion. GNARL is distributed in the hope that it will be useful, but WITH- --
-- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
-- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
-- for more details. You should have received a copy of the GNU General --
-- Public License distributed with GNARL; see file COPYING. If not, write --
-- to the Free Software Foundation, 51 Franklin Street, Fifth Floor, --
-- Boston, MA 02110-1301, USA. --
-- --
-- As a special exception, if other files instantiate generics from this --
-- unit, or you link this unit with other files to produce an executable, --
-- this unit does not by itself cause the resulting executable to be --
-- covered by the GNU General Public License. This exception does not --
-- however invalidate any other reasons why the executable file might be --
-- covered by the GNU Public License. --
-- --
-- GNARL was developed by the GNARL team at Florida State University. --
-- Extensive contributions were provided by Ada Core Technologies, Inc. --
-- --
------------------------------------------------------------------------------
-- This is the Alpha/VMS version
with System.OS_Primitives;
with System.Soft_Links;
package body Ada.Calendar.Delays is
package OSP renames System.OS_Primitives;
package TSL renames System.Soft_Links;
use type TSL.Timed_Delay_Call;
-----------------------
-- Local Subprograms --
-----------------------
procedure Timed_Delay_NT (Time : Duration; Mode : Integer);
-- Timed delay procedure used when no tasking is active
---------------
-- Delay_For --
---------------
procedure Delay_For (D : Duration) is
begin
TSL.Timed_Delay.all
(Duration'Min (D, OSP.Max_Sensible_Delay), OSP.Relative);
end Delay_For;
-----------------
-- Delay_Until --
-----------------
procedure Delay_Until (T : Time) is
begin
TSL.Timed_Delay.all (To_Duration (T), OSP.Absolute_Calendar);
end Delay_Until;
-----------------
-- To_Duration --
-----------------
function To_Duration (T : Time) return Duration is
Safe_Ada_High : constant Time := Time_Of (2250, 1, 1, 0.0);
-- A value distant enough to emulate "end of time" but which does not
-- cause overflow.
Safe_T : constant Time :=
(if T > Safe_Ada_High then Safe_Ada_High else T);
begin
return OSP.To_Duration (OSP.OS_Time (Safe_T), OSP.Absolute_Calendar);
end To_Duration;
--------------------
-- Timed_Delay_NT --
--------------------
procedure Timed_Delay_NT (Time : Duration; Mode : Integer) is
begin
OSP.Timed_Delay (Time, Mode);
end Timed_Delay_NT;
begin
-- Set up the Timed_Delay soft link to the non tasking version if it has
-- not been already set. If tasking is present, Timed_Delay has already set
-- this soft link, or this will be overridden during the elaboration of
-- System.Tasking.Initialization
if TSL.Timed_Delay = null then
TSL.Timed_Delay := Timed_Delay_NT'Access;
end if;
end Ada.Calendar.Delays;
|
