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------------------------------------------------------------------------------
-- --
-- GNU ADA RUN-TIME LIBRARY (GNARL) COMPONENTS --
-- --
-- S Y S T E M . O S _ P R I M I T I V E S --
-- --
-- B o d y --
-- --
-- $Revision: 1.4 $ --
-- --
-- Copyright (C) 1998-2001 Free Software Foundation, Inc. --
-- --
-- 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, 59 Temple Place - Suite 330, Boston, --
-- MA 02111-1307, 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. It is --
-- now maintained by Ada Core Technologies Inc. in cooperation with Florida --
-- State University (http://www.gnat.com). --
-- --
------------------------------------------------------------------------------
-- This version is for POSIX-like operating systems
package body System.OS_Primitives is
-- ??? These definitions are duplicated from System.OS_Interface
-- because we don't want to depend on any package. Consider removing
-- these declarations in System.OS_Interface and move these ones in
-- the spec.
type struct_timezone is record
tz_minuteswest : Integer;
tz_dsttime : Integer;
end record;
pragma Convention (C, struct_timezone);
type struct_timezone_ptr is access all struct_timezone;
type time_t is new Integer;
type struct_timeval is record
tv_sec : time_t;
tv_usec : Integer;
end record;
pragma Convention (C, struct_timeval);
function gettimeofday
(tv : access struct_timeval;
tz : struct_timezone_ptr) return Integer;
pragma Import (C, gettimeofday, "gettimeofday");
type timespec is record
tv_sec : time_t;
tv_nsec : Long_Integer;
end record;
pragma Convention (C, timespec);
function nanosleep (rqtp, rmtp : access timespec) return Integer;
pragma Import (C, nanosleep, "nanosleep");
-----------
-- Clock --
-----------
function Clock return Duration is
TV : aliased struct_timeval;
Result : Integer;
begin
Result := gettimeofday (TV'Access, null);
return Duration (TV.tv_sec) + Duration (TV.tv_usec) / 10#1#E6;
end Clock;
---------------------
-- Monotonic_Clock --
---------------------
function Monotonic_Clock return Duration renames Clock;
-----------------
-- To_Timespec --
-----------------
function To_Timespec (D : Duration) return timespec;
function To_Timespec (D : Duration) return timespec is
S : time_t;
F : Duration;
begin
S := time_t (Long_Long_Integer (D));
F := D - Duration (S);
-- If F has negative value due to a round-up, adjust for positive F
-- value.
if F < 0.0 then
S := S - 1;
F := F + 1.0;
end if;
return timespec' (tv_sec => S,
tv_nsec => Long_Integer (Long_Long_Integer (F * 10#1#E9)));
end To_Timespec;
-----------------
-- Timed_Delay --
-----------------
procedure Timed_Delay
(Time : Duration;
Mode : Integer)
is
Request : aliased timespec;
Remaind : aliased timespec;
Result : Integer;
Rel_Time : Duration;
Abs_Time : Duration;
Check_Time : Duration := Clock;
begin
if Mode = Relative then
Rel_Time := Time;
Abs_Time := Time + Check_Time;
else
Rel_Time := Time - Check_Time;
Abs_Time := Time;
end if;
if Rel_Time > 0.0 then
loop
Request := To_Timespec (Rel_Time);
Result := nanosleep (Request'Access, Remaind'Access);
Check_Time := Clock;
exit when Abs_Time <= Check_Time;
Rel_Time := Abs_Time - Check_Time;
end loop;
end if;
end Timed_Delay;
end System.OS_Primitives;
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