(*
Title    : DynMem - part of storage managing a one block heap
Creation : 87/02/19
Author   : A.Richard
System   : LOGITECH MODULA-2/86

Last Edit: 87.04.01
*)
DEFINITION MODULE DynMem;

(*
   DynMem is used by Storage in order to manage one-block heap (16 k)
*)

FROM SYSTEM  IMPORT ADDRESS;

EXPORT QUALIFIED  InstallDynMem, Alloc, DeAlloc, Avail;

(* for all procedures below, the block address must be paragraph aligned   *)
(* with offset 0                                                           *)

PROCEDURE InstallDynMem( block : ADDRESS; size : CARDINAL );
(* size is the size in bytes usable by DynMem and it must be < MaxInt      *)

PROCEDURE Alloc( block : ADDRESS; VAR adr : ADDRESS; size : CARDINAL );
(* adr will be the allocated block address or NIL if no space available    *)
(* size is in bytes                                                        *)

PROCEDURE DeAlloc( block : ADDRESS;
                   VAR adr : ADDRESS; size : CARDINAL ): BOOLEAN;
(* adr return value will be NIL                                            *)

PROCEDURE Avail( block : ADDRESS; size : CARDINAL ): BOOLEAN;
(* returns TRUE if size is available in the block                          *)

END DynMem.