------------------------------------------------------------------------------ -- -- -- GNAT RUNTIME COMPONENTS -- -- -- -- S Y S T E M . D I R E C T _ I O -- -- -- -- S p e c -- -- -- -- Copyright (C) 1992,1993,1994,1995,1996 Free Software Foundation, Inc. -- -- -- -- GNAT 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. GNAT 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 GNAT; 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. -- -- -- -- GNAT was originally developed by the GNAT team at New York University. -- -- Extensive contributions were provided by Ada Core Technologies Inc. -- -- -- ------------------------------------------------------------------------------ -- This package contains the declaration of the control block used for -- Direct_IO. This must be declared at the outer library level. It also -- contains code that is shared between instances of Direct_IO. with Interfaces.C_Streams; with Ada.Streams; with System.File_Control_Block; with System.Storage_Elements; package System.Direct_IO is package FCB renames System.File_Control_Block; type Operation is (Op_Read, Op_Write, Op_Other); -- Type used to record last operation (to optimize sequential operations) subtype Count is Interfaces.C_Streams.long; -- The Count type in each instantiation is derived from this type subtype Positive_Count is Count range 1 .. Count'Last; type Direct_AFCB is new FCB.AFCB with record Index : Count := 1; -- Current Index value Bytes : Interfaces.C_Streams.size_t; -- Length of item in bytes (set from inside generic template) Last_Op : Operation := Op_Other; -- Last operation performed on file, used to avoid unnecessary -- repositioning between successive read or write operations. end record; function AFCB_Allocate (Control_Block : Direct_AFCB) return FCB.AFCB_Ptr; procedure AFCB_Close (File : access Direct_AFCB); procedure AFCB_Free (File : access Direct_AFCB); procedure Read (File : in out Direct_AFCB; Item : out Ada.Streams.Stream_Element_Array; Last : out Ada.Streams.Stream_Element_Offset); -- Required overriding of Read, not actually used for Direct_IO procedure Write (File : in out Direct_AFCB; Item : in Ada.Streams.Stream_Element_Array); -- Required overriding of Write, not actually used for Direct_IO type File_Type is access all Direct_AFCB; -- File_Type in individual instantiations is derived from this type procedure Create (File : in out File_Type; Mode : in FCB.File_Mode := FCB.Inout_File; Name : in String := ""; Form : in String := ""); function End_Of_File (File : in File_Type) return Boolean; function Index (File : in File_Type) return Positive_Count; procedure Open (File : in out File_Type; Mode : in FCB.File_Mode; Name : in String; Form : in String := ""); procedure Read (File : in File_Type; Item : System.Address; Size : in Interfaces.C_Streams.size_t; From : in Positive_Count); procedure Read (File : in File_Type; Item : System.Address; Size : in Interfaces.C_Streams.size_t); procedure Reset (File : in out File_Type; Mode : in FCB.File_Mode); procedure Reset (File : in out File_Type); procedure Set_Index (File : in File_Type; To : in Positive_Count); function Size (File : in File_Type) return Count; procedure Write (File : in File_Type; Item : System.Address; Size : in Interfaces.C_Streams.size_t; Zeroes : System.Storage_Elements.Storage_Array); -- Note: Zeroes is the buffer of zeroes used to fill out partial records end System.Direct_IO;