1 ------------------------------------------------------------------------------
3 -- GNU ADA RUN-TIME LIBRARY (GNARL) COMPONENTS --
5 -- A D A . C A L E N D A R . D E L A Y S --
10 -- Copyright (C) 1991-2001 Florida State University --
12 -- GNARL 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 2, or (at your option) any later ver- --
15 -- sion. GNARL 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. See the GNU General Public License --
18 -- for more details. You should have received a copy of the GNU General --
19 -- Public License distributed with GNARL; see file COPYING. If not, write --
20 -- to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, --
21 -- MA 02111-1307, USA. --
23 -- As a special exception, if other files instantiate generics from this --
24 -- unit, or you link this unit with other files to produce an executable, --
25 -- this unit does not by itself cause the resulting executable to be --
26 -- covered by the GNU General Public License. This exception does not --
27 -- however invalidate any other reasons why the executable file might be --
28 -- covered by the GNU Public License. --
30 -- GNARL was developed by the GNARL team at Florida State University. It is --
31 -- now maintained by Ada Core Technologies Inc. in cooperation with Florida --
32 -- State University (http://www.gnat.com). --
34 ------------------------------------------------------------------------------
36 with System
.OS_Primitives
;
37 -- Used for Delay_Modes
40 with System
.Soft_Links
;
41 -- Used for Timed_Delay
44 -- Used for Send_Trace_Info
46 with System
.Parameters
;
47 -- used for Runtime_Traces
49 package body Ada
.Calendar
.Delays
is
51 package OSP
renames System
.OS_Primitives
;
52 package SSL
renames System
.Soft_Links
;
54 use type SSL
.Timed_Delay_Call
;
58 -- Earlier, the following operations were implemented using
59 -- System.Time_Operations. The idea was to avoid sucking in the tasking
60 -- packages. This did not work. Logically, we can't have it both ways.
61 -- There is no way to implement time delays that will have correct task
62 -- semantics without reference to the tasking run-time system.
63 -- To achieve this goal, we now use soft links.
65 -----------------------
66 -- Local Subprograms --
67 -----------------------
69 procedure Timed_Delay_NT
(Time
: Duration; Mode
: Integer);
70 -- Timed delay procedure used when no tasking is active
76 procedure Delay_For
(D
: Duration) is
78 if System
.Parameters
.Runtime_Traces
then
79 Send_Trace_Info
(W_Delay
, D
);
82 SSL
.Timed_Delay
.all (Duration'Min (D
, OSP
.Max_Sensible_Delay
),
85 if System
.Parameters
.Runtime_Traces
then
86 Send_Trace_Info
(M_Delay
, D
);
94 procedure Delay_Until
(T
: Time
) is
95 D
: constant Duration := To_Duration
(T
);
98 if System
.Parameters
.Runtime_Traces
then
99 Send_Trace_Info
(WU_Delay
, D
);
102 SSL
.Timed_Delay
.all (D
, OSP
.Absolute_Calendar
);
104 if System
.Parameters
.Runtime_Traces
then
105 Send_Trace_Info
(M_Delay
, D
);
113 procedure Timed_Delay_NT
(Time
: Duration; Mode
: Integer) is
115 OSP
.Timed_Delay
(Time
, Mode
);
122 function To_Duration
(T
: Time
) return Duration is
128 -- Set up the Timed_Delay soft link to the non tasking version
129 -- if it has not been already set.
131 -- If tasking is present, Timed_Delay has already set this soft
132 -- link, or this will be overriden during the elaboration of
133 -- System.Tasking.Initialization
135 if SSL
.Timed_Delay
= null then
136 SSL
.Timed_Delay
:= Timed_Delay_NT
'Access;
138 end Ada
.Calendar
.Delays
;