1------------------------------------------------------------------------------ 2-- -- 3-- GNAT RUN-TIME LIBRARY (GNARL) COMPONENTS -- 4-- -- 5-- A D A . C A L E N D A R . D E L A Y S -- 6-- -- 7-- B o d y -- 8-- -- 9-- Copyright (C) 1991-1994, Florida State University -- 10-- Copyright (C) 1995-2010, AdaCore -- 11-- -- 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. -- 18-- -- 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. -- 22-- -- 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/>. -- 27-- -- 28-- GNARL was developed by the GNARL team at Florida State University. -- 29-- Extensive contributions were provided by Ada Core Technologies, Inc. -- 30-- -- 31------------------------------------------------------------------------------ 32 33with System.OS_Primitives; 34with System.Soft_Links; 35with System.Traces; 36with System.Parameters; 37 38package body Ada.Calendar.Delays is 39 40 package OSP renames System.OS_Primitives; 41 package SSL renames System.Soft_Links; 42 43 use type SSL.Timed_Delay_Call; 44 45 use System.Traces; 46 47 -- Earlier, System.Time_Operations was used to implement the following 48 -- operations. The idea was to avoid sucking in the tasking packages. This 49 -- did not work. Logically, we can't have it both ways. There is no way to 50 -- implement time delays that will have correct task semantics without 51 -- reference to the tasking run-time system. To achieve this goal, we now 52 -- use soft links. 53 54 ----------------------- 55 -- Local Subprograms -- 56 ----------------------- 57 58 procedure Timed_Delay_NT (Time : Duration; Mode : Integer); 59 -- Timed delay procedure used when no tasking is active 60 61 --------------- 62 -- Delay_For -- 63 --------------- 64 65 procedure Delay_For (D : Duration) is 66 begin 67 if System.Parameters.Runtime_Traces then 68 Send_Trace_Info (W_Delay, D); 69 end if; 70 71 SSL.Timed_Delay.all (Duration'Min (D, OSP.Max_Sensible_Delay), 72 OSP.Relative); 73 74 if System.Parameters.Runtime_Traces then 75 Send_Trace_Info (M_Delay, D); 76 end if; 77 end Delay_For; 78 79 ----------------- 80 -- Delay_Until -- 81 ----------------- 82 83 procedure Delay_Until (T : Time) is 84 D : constant Duration := To_Duration (T); 85 86 begin 87 if System.Parameters.Runtime_Traces then 88 Send_Trace_Info (WU_Delay, D); 89 end if; 90 91 SSL.Timed_Delay.all (D, OSP.Absolute_Calendar); 92 93 if System.Parameters.Runtime_Traces then 94 Send_Trace_Info (M_Delay, D); 95 end if; 96 end Delay_Until; 97 98 -------------------- 99 -- Timed_Delay_NT -- 100 -------------------- 101 102 procedure Timed_Delay_NT (Time : Duration; Mode : Integer) is 103 begin 104 OSP.Timed_Delay (Time, Mode); 105 end Timed_Delay_NT; 106 107 ----------------- 108 -- To_Duration -- 109 ----------------- 110 111 function To_Duration (T : Time) return Duration is 112 begin 113 -- Since time has multiple representations on different platforms, a 114 -- target independent operation in Ada.Calendar is used to perform 115 -- this conversion. 116 117 return Delay_Operations.To_Duration (T); 118 end To_Duration; 119 120begin 121 -- Set up the Timed_Delay soft link to the non tasking version if it has 122 -- not been already set. If tasking is present, Timed_Delay has already set 123 -- this soft link, or this will be overridden during the elaboration of 124 -- System.Tasking.Initialization 125 126 if SSL.Timed_Delay = null then 127 SSL.Timed_Delay := Timed_Delay_NT'Access; 128 end if; 129 130end Ada.Calendar.Delays; 131