(* wraptime.def provides access to time primitives.

Copyright (C) 2009-2023 Free Software Foundation, Inc.
Contributed by Gaius Mulley <gaius.mulley@southwales.ac.uk>.

This file is part of GNU Modula-2.

GNU Modula-2 is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3, or (at your option)
any later version.

GNU Modula-2 is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
General Public License for more details.

Under Section 7 of GPL version 3, you are granted additional
permissions described in the GCC Runtime Library Exception, version
3.1, as published by the Free Software Foundation.

You should have received a copy of the GNU General Public License and
a copy of the GCC Runtime Library Exception along with this program;
see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
<http://www.gnu.org/licenses/>.  *)

DEFINITION MODULE wraptime ;

(*
    Title      : wraptime
    Author     : Gaius Mulley
    System     : GNU Modula-2
    Date       : Sun Mar  1 21:41:29 2009
    Revision   : $Version$ 
    Description: provides an interface to various time related
                 entities on the underlying host operating system.
                 It provides access to the glibc/libc functions:
                 gettimeofday, settimeofday and localtime_r.
*)

FROM SYSTEM IMPORT ADDRESS ;

TYPE
   timeval  = ADDRESS ;
   timezone = ADDRESS ;
   tm       = ADDRESS ;


(*
   InitTimeval - returns a newly created opaque type.
*)

PROCEDURE InitTimeval () : timeval ;


(*
   KillTimeval - deallocates the memory associated with an
                 opaque type.
*)

PROCEDURE KillTimeval (tv: timeval) : timeval ;


(*
   InitTimezone - returns a newly created opaque type.
*)

PROCEDURE InitTimezone () : timezone ;


(*
   KillTimezone - deallocates the memory associated with an
                  opaque type.
*)

PROCEDURE KillTimezone (tv: timezone) : timezone ;


(*
   InitTM - returns a newly created opaque type.
*)

PROCEDURE InitTM () : tm ;


(*
   KillTM - deallocates the memory associated with an
            opaque type.
*)

PROCEDURE KillTM (tv: tm) : tm ;


(*
   gettimeofday - calls gettimeofday(2) with the same parameters, tv,
                  and, tz.  It returns 0 on success.
*)

PROCEDURE gettimeofday (tv: timeval; tz: timezone) : INTEGER ;


(*
   settimeofday - calls settimeofday(2) with the same parameters, tv,
                  and, tz.  It returns 0 on success.
*)

PROCEDURE settimeofday (tv: timeval; tz: timezone) : INTEGER ;


(*
   GetFractions - returns the tv_usec field inside the timeval structure
                  as a CARDINAL.
*)

PROCEDURE GetFractions (tv: timeval) : CARDINAL ;


(*
   localtime_r - returns the tm parameter, m, after it has been assigned with
                 appropriate contents determined by, tv.  Notice that
                 this procedure function expects, timeval, as its first
                 parameter and not a time_t (as expected by the posix
                 equivalent).  This avoids having to expose a time_t
                 system dependant definition.
*)

PROCEDURE localtime_r (tv: timeval; m: tm) : tm ;


(*
   GetYear - returns the year from the structure, m.
*)

PROCEDURE GetYear (m: tm) : CARDINAL ;


(*
   GetMonth - returns the month from the structure, m.
*)

PROCEDURE GetMonth (m: tm) : CARDINAL ;


(*
   GetDay - returns the day of the month from the structure, m.
*)

PROCEDURE GetDay (m: tm) : CARDINAL ;


(*
   GetHour - returns the hour of the day from the structure, m.
*)

PROCEDURE GetHour (m: tm) : CARDINAL ;


(*
   GetMinute - returns the minute within the hour from the structure, m.
*)

PROCEDURE GetMinute (m: tm) : CARDINAL ;


(*
   GetSecond - returns the seconds in the minute from the structure, m.
               The return value will always be in the range 0..59.
               A leap minute of value 60 will be truncated to 59.
*)

PROCEDURE GetSecond (m: tm) : CARDINAL ;


(*
   GetSummerTime - returns a boolean indicating whether summer time is
                   set.
*)

PROCEDURE GetSummerTime (tz: timezone) : BOOLEAN ;


(*
   GetDST - returns the number of minutes west of GMT.
*)

PROCEDURE GetDST (tz: timezone) : INTEGER ;


(*
   SetTimeval - sets the fields in timeval, tv, with:
                second, minute, hour, day, month, year, fractions.
*)

PROCEDURE SetTimeval (tv: timeval;
                      second, minute, hour, day,
                      month, year, yday, wday, isdst: CARDINAL) ;


(*
   SetTimezone - set the timezone field inside timeval, tv.
*)

PROCEDURE SetTimezone (tv: timeval;
                       zone: CARDINAL; minuteswest: INTEGER) ;


END wraptime.