1 ------------------------------------------------------------------------------
3 -- GNAT RUN-TIME COMPONENTS --
5 -- S Y S T E M . O S _ P R I M I T I V E S. T I M E D _ D E L A Y --
9 -- Copyright (C) 2012-2023, AdaCore --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. --
18 -- As a special exception under Section 7 of GPL version 3, you are granted --
19 -- additional permissions described in the GCC Runtime Library Exception, --
20 -- version 3.1, as published by the Free Software Foundation. --
22 -- You should have received a copy of the GNU General Public License and --
23 -- a copy of the GCC Runtime Library Exception along with this program; --
24 -- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see --
25 -- <http://www.gnu.org/licenses/>. --
27 -- GNAT was originally developed by the GNAT team at New York University. --
28 -- Extensive contributions were provided by Ada Core Technologies Inc. --
30 ------------------------------------------------------------------------------
32 -- This is the Posix, Posix2008, and LynxOS version of this procedure.
34 separate (System
.OS_Primitives
)
39 Request
: aliased timespec
;
40 Remaind
: aliased timespec
;
43 Base_Time
: constant Duration := Clock
;
44 Check_Time
: Duration := Base_Time
;
45 Time_Chunk
: Duration;
48 pragma Unreferenced
(Result
);
51 if Mode
= Relative
then
53 Abs_Time
:= Time
+ Check_Time
;
55 Rel_Time
:= Time
- Check_Time
;
59 -- To keep a sensible Max_Sensible_Delay on a target whose system
60 -- maximum is less than sensible, we split the delay into manageable
61 -- chunks of time less than or equal to the Max_System_Delay.
63 if Rel_Time
> 0.0 then
64 Time_Chunk
:= Rel_Time
;
66 pragma Warnings
(Off
, "condition is always *");
67 if Max_System_Delay
< Max_Sensible_Delay
and then
68 Time_Chunk
> Max_System_Delay
70 Time_Chunk
:= Max_System_Delay
;
74 Request
:= To_Timespec
(Time_Chunk
);
75 Result
:= nanosleep
(Request
'Access, Remaind
'Access);
79 exit when Abs_Time
<= Check_Time
or else Check_Time
< Base_Time
;
81 Time_Chunk
:= Abs_Time
- Check_Time
;