1 ------------------------------------------------------------------------------
3 -- GNAT RUN-TIME LIBRARY (GNARL) COMPONENTS --
5 -- A D A . C A L E N D A R . D E L A Y S --
9 -- Copyright (C) 1991-1994, Florida State University --
10 -- Copyright (C) 1995-2010, AdaCore --
12 -- GNAT is free software; you can redistribute it and/or modify it under --
13 -- terms of the GNU General Public License as published by the Free Soft- --
14 -- ware Foundation; either version 3, or (at your option) any later ver- --
15 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
16 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
17 -- or FITNESS FOR A PARTICULAR PURPOSE. --
19 -- As a special exception under Section 7 of GPL version 3, you are granted --
20 -- additional permissions described in the GCC Runtime Library Exception, --
21 -- version 3.1, as published by the Free Software Foundation. --
23 -- You should have received a copy of the GNU General Public License and --
24 -- a copy of the GCC Runtime Library Exception along with this program; --
25 -- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see --
26 -- <http://www.gnu.org/licenses/>. --
28 -- GNARL was developed by the GNARL team at Florida State University. --
29 -- Extensive contributions were provided by Ada Core Technologies, Inc. --
31 ------------------------------------------------------------------------------
33 -- This is the Alpha/VMS version
35 with System.OS_Primitives;
36 with System.Soft_Links;
38 package body Ada.Calendar.Delays is
40 package OSP renames System.OS_Primitives;
41 package TSL renames System.Soft_Links;
43 use type TSL.Timed_Delay_Call;
45 -----------------------
46 -- Local Subprograms --
47 -----------------------
49 procedure Timed_Delay_NT (Time : Duration; Mode : Integer);
50 -- Timed delay procedure used when no tasking is active
56 procedure Delay_For (D : Duration) is
59 (Duration'Min (D, OSP.Max_Sensible_Delay), OSP.Relative);
66 procedure Delay_Until (T : Time) is
68 TSL.Timed_Delay.all (To_Duration (T), OSP.Absolute_Calendar);
75 function To_Duration (T : Time) return Duration is
76 Safe_Ada_High : constant Time := Time_Of (2250, 1, 1, 0.0);
77 -- A value distant enough to emulate "end of time" but which does not
80 Safe_T : constant Time :=
81 (if T > Safe_Ada_High then Safe_Ada_High else T);
84 return OSP.To_Duration (OSP.OS_Time (Safe_T), OSP.Absolute_Calendar);
91 procedure Timed_Delay_NT (Time : Duration; Mode : Integer) is
93 OSP.Timed_Delay (Time, Mode);
97 -- Set up the Timed_Delay soft link to the non tasking version if it has
98 -- not been already set. If tasking is present, Timed_Delay has already set
99 -- this soft link, or this will be overridden during the elaboration of
100 -- System.Tasking.Initialization
102 if TSL.Timed_Delay = null then
103 TSL.Timed_Delay := Timed_Delay_NT'Access;
105 end Ada.Calendar.Delays;