(* RTdata.def provides a mechanism whereby devices can attach data.

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 RTdata ;

(*
    Title      : RTdata
    Author     : Gaius Mulley
    System     : GNU Modula-2
    Date       : Fri Sep 26 17:19:15 2008
    Revision   : $Version$ 
    Description: provides a mechanism whereby devices can store
                 data attached to a device.
*)

FROM SYSTEM IMPORT ADDRESS ;
FROM IOLink IMPORT DeviceTablePtr ;

TYPE
   ModuleId ;
   FreeProcedure = PROCEDURE (ADDRESS) ;


(*
   MakeModuleId - creates a unique module Id.
*)

PROCEDURE MakeModuleId (VAR m: ModuleId) ;


(*
   InitData - adds, datum, to the device, d.  The datum
              is associated with ModuleID, m.
*)

PROCEDURE InitData (d: DeviceTablePtr; m: ModuleId;
                    datum: ADDRESS; f: FreeProcedure) ;


(*
   GetData - returns the datum assocated with ModuleId, m.
*)

PROCEDURE GetData (d: DeviceTablePtr; m: ModuleId) : ADDRESS ;


(*
   KillData - destroys the datum associated with ModuleId, m,
              in device, d.  It invokes the free procedure
              given during InitData.
*)

PROCEDURE KillData (d: DeviceTablePtr; m: ModuleId) ;


END RTdata.