(* RTgen.def provide a generic device interface used by ISO.

Copyright (C) 2008-2023 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 RTgen ;

(*
    Title      : RTgen
    Author     : Gaius Mulley
    System     : GNU Modula-2
    Date       : Mon Sep 22 18:15:35 2008
    Revision   : $Version$ 
    Description: provides a generic device interface between
                 ISO channels and the underlying PIM style
                 FIO procedure calls.
*)

FROM RTgenif IMPORT GenDevIF ;
FROM IOLink IMPORT DeviceId, DeviceTablePtr;
FROM IOConsts IMPORT ReadResults ;
FROM SYSTEM IMPORT ADDRESS ;


TYPE
   ChanDev ;
   DeviceType = (seqfile, streamfile, programargs, stdchans, term, socket, rndfile) ;


(*
   InitChanDev - initialize and return a ChanDev.
*)

PROCEDURE InitChanDev (t: DeviceType; d: DeviceId; g: GenDevIF) : ChanDev ;


(*
   KillChanDev - deallocates, g.
*)

PROCEDURE KillChanDev (g: GenDevIF) : GenDevIF ;


(*
   RaiseEOFinLook - returns TRUE if the Look procedure
                    should raise an exception if it
                    sees end of file.
*)

PROCEDURE RaiseEOFinLook (g: ChanDev) : BOOLEAN ;


(*
   RaiseEOFinSkip - returns TRUE if the Skip procedure
                    should raise an exception if it
                    sees end of file.
*)

PROCEDURE RaiseEOFinSkip (g: ChanDev) : BOOLEAN ;


PROCEDURE doLook (g: ChanDev;
                  d: DeviceTablePtr;
                  VAR ch: CHAR;
                  VAR r: ReadResults) ;

PROCEDURE doSkip (g: ChanDev;
                  d: DeviceTablePtr) ;

PROCEDURE doSkipLook (g: ChanDev;
                      d: DeviceTablePtr;
                      VAR ch: CHAR;
                      VAR r: ReadResults) ;

PROCEDURE doWriteLn (g: ChanDev;
                     d: DeviceTablePtr) ;

PROCEDURE doReadText (g: ChanDev;
                      d: DeviceTablePtr;
                      to: ADDRESS;
                      maxChars: CARDINAL;
                      VAR charsRead: CARDINAL) ;

PROCEDURE doWriteText (g: ChanDev;
                       d: DeviceTablePtr;
                       from: ADDRESS;
                       charsToWrite: CARDINAL) ;

PROCEDURE doReadLocs (g: ChanDev;
                      d: DeviceTablePtr;
                      to: ADDRESS;
                      maxLocs: CARDINAL;
                      VAR locsRead: CARDINAL) ;

PROCEDURE doWriteLocs (g: ChanDev;
                       d: DeviceTablePtr;
                       from: ADDRESS;
                       locsToWrite: CARDINAL) ;

(*
   checkErrno - checks a number of errno conditions and raises
                appropriate ISO exceptions if they occur.
*)

PROCEDURE checkErrno (g: ChanDev; d: DeviceTablePtr) ;


END RTgen.