------------------------------------------------------------------------------ -- -- -- 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 -- -- -- -- -- -- 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. -- -- Extensive contributions were provided by Ada Core Technologies Inc. -- -- -- ------------------------------------------------------------------------------ -- This version is for VxWorks targets with System.OS_Interface; -- Since the thread library is part of the VxWorks kernel, using OS_Interface -- is not a problem here, as long as we only use System.OS_Interface as a -- set of C imported routines: using Ada routines from this package would -- create a dependency on libgnarl in libgnat, which is not desirable. with Interfaces.C; -- used for type int package body System.OS_Primitives is use System.OS_Interface; -------------------------- -- Internal functions -- -------------------------- function To_Clock_Ticks (D : Duration) return int; -- Convert a duration value (in seconds) into clock ticks. -- Note that this routine is duplicated from System.OS_Interface since -- as explained above, we do not want to depend on libgnarl function To_Clock_Ticks (D : Duration) return int is Ticks : Long_Long_Integer; Rate_Duration : Duration; Ticks_Duration : Duration; begin -- 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 -- We always want to round up to the nearest clock tick. 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; ----------- -- Clock -- ----------- function Clock return Duration is TS : aliased timespec; Result : int; use type Interfaces.C.int; begin Result := clock_gettime (CLOCK_REALTIME, TS'Unchecked_Access); pragma Assert (Result = 0); return Duration (TS.ts_sec) + Duration (TS.ts_nsec) / 10#1#E9; end Clock; --------------------- -- Monotonic_Clock -- --------------------- function Monotonic_Clock return Duration renames Clock; ----------------- -- Timed_Delay -- ----------------- procedure Timed_Delay (Time : Duration; Mode : Integer) is Result : int; 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 Result := taskDelay (To_Clock_Ticks (Rel_Time)); 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;