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------------------------------------------------------------------------------
-- --
-- GNU ADA RUN-TIME LIBRARY (GNARL) COMPONENTS --
-- --
-- S Y S T E M . O S _ I N T E R F A C E --
-- --
-- B o d y --
-- --
-- Copyright (C) 1997-2002 Free Software Foundation --
-- --
-- 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. --
-- Extensive contributions were provided by Ada Core Technologies, Inc. --
-- --
------------------------------------------------------------------------------
-- This is the VxWorks version.
-- This package encapsulates all direct interfaces to OS services
-- that are needed by children of System.
pragma Polling (Off);
-- Turn off polling, we do not want ATC polling to take place during
-- tasking operations. It causes infinite loops and other problems.
package body System.OS_Interface is
use type Interfaces.C.int;
Low_Priority : constant := 255;
-- VxWorks native (default) lowest scheduling priority.
-------------
-- sigwait --
-------------
function sigwait
(set : access sigset_t;
sig : access Signal) return int
is
Result : int;
function sigwaitinfo
(set : access sigset_t; sigvalue : System.Address) return int;
pragma Import (C, sigwaitinfo, "sigwaitinfo");
begin
Result := sigwaitinfo (set, System.Null_Address);
if Result /= -1 then
sig.all := Signal (Result);
return 0;
else
sig.all := 0;
return errno;
end if;
end sigwait;
-----------------
-- To_Duration --
-----------------
function To_Duration (TS : timespec) return Duration is
begin
return Duration (TS.ts_sec) + Duration (TS.ts_nsec) / 10#1#E9;
end To_Duration;
-----------------
-- To_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'(ts_sec => S,
ts_nsec => long (Long_Long_Integer (F * 10#1#E9)));
end To_Timespec;
-------------------------
-- To_VxWorks_Priority --
-------------------------
function To_VxWorks_Priority (Priority : in int) return int is
begin
return Low_Priority - Priority;
end To_VxWorks_Priority;
--------------------
-- To_Clock_Ticks --
--------------------
-- ??? - For now, we'll always get the system clock rate
-- since it is allowed to be changed during run-time in
-- VxWorks. A better method would be to provide an operation
-- to set it that so we can always know its value.
--
-- Another thing we should probably allow for is a resultant
-- tick count greater than int'Last. This should probably
-- be a procedure with two output parameters, one in the
-- range 0 .. int'Last, and another representing the overflow
-- count.
function To_Clock_Ticks (D : Duration) return int is
Ticks : Long_Long_Integer;
Rate_Duration : Duration;
Ticks_Duration : Duration;
begin
if D < 0.0 then
return -1;
end if;
-- Ensure that the duration can be converted to ticks
-- at the current clock tick rate without overflowing.
Rate_Duration := Duration (sysClkRateGet);
if D > (Duration'Last / Rate_Duration) then
Ticks := Long_Long_Integer (int'Last);
else
Ticks_Duration := D * Rate_Duration;
Ticks := Long_Long_Integer (Ticks_Duration);
if Ticks_Duration > Duration (Ticks) then
Ticks := Ticks + 1;
end if;
if Ticks > Long_Long_Integer (int'Last) then
Ticks := Long_Long_Integer (int'Last);
end if;
end if;
return int (Ticks);
end To_Clock_Ticks;
end System.OS_Interface;
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