| ------------------------------------------------------------------------------ |
| -- -- |
| -- 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; |
