| ------------------------------------------------------------------------------ | 
 | --                                                                          -- | 
 | --                         GNAT RUN-TIME COMPONENTS                         -- | 
 | --                                                                          -- | 
 | --                        A D A . D I R E C T _ I O                         -- | 
 | --                                                                          -- | 
 | --                                 B o d y                                  -- | 
 | --                                                                          -- | 
 | --          Copyright (C) 1992-2006, 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,  51  Franklin  Street,  Fifth  Floor, -- | 
 | -- Boston, MA 02110-1301, 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 is the generic template for Direct_IO, i.e. the code that gets | 
 | --  duplicated. We absolutely minimize this code by either calling routines | 
 | --  in System.File_IO (for common file functions), or in System.Direct_IO | 
 | --  (for specialized Direct_IO functions) | 
 |  | 
 | with Interfaces.C_Streams; use Interfaces.C_Streams; | 
 | with System;               use System; | 
 | with System.CRTL; | 
 | with System.File_Control_Block; | 
 | with System.File_IO; | 
 | with System.Direct_IO; | 
 | with System.Storage_Elements; | 
 | with Unchecked_Conversion; | 
 |  | 
 | use type System.Direct_IO.Count; | 
 |  | 
 | package body Ada.Direct_IO is | 
 |  | 
 |    Zeroes : constant System.Storage_Elements.Storage_Array := | 
 |               (1 .. System.Storage_Elements.Storage_Offset (Bytes) => 0); | 
 |    --  Buffer used to fill out partial records | 
 |  | 
 |    package FCB renames System.File_Control_Block; | 
 |    package FIO renames System.File_IO; | 
 |    package DIO renames System.Direct_IO; | 
 |  | 
 |    SU : constant := System.Storage_Unit; | 
 |  | 
 |    subtype AP      is FCB.AFCB_Ptr; | 
 |    subtype FP      is DIO.File_Type; | 
 |    subtype DPCount is DIO.Positive_Count; | 
 |  | 
 |    function To_FCB is new Unchecked_Conversion (File_Mode, FCB.File_Mode); | 
 |    function To_DIO is new Unchecked_Conversion (FCB.File_Mode, File_Mode); | 
 |  | 
 |    use type System.CRTL.size_t; | 
 |  | 
 |    ----------- | 
 |    -- Close -- | 
 |    ----------- | 
 |  | 
 |    procedure Close (File : in out File_Type) is | 
 |    begin | 
 |       FIO.Close (AP (File)); | 
 |    end Close; | 
 |  | 
 |    ------------ | 
 |    -- Create -- | 
 |    ------------ | 
 |  | 
 |    procedure Create | 
 |      (File : in out File_Type; | 
 |       Mode : File_Mode := Inout_File; | 
 |       Name : String := ""; | 
 |       Form : String := "") | 
 |    is | 
 |    begin | 
 |       DIO.Create (FP (File), To_FCB (Mode), Name, Form); | 
 |       File.Bytes := Bytes; | 
 |    end Create; | 
 |  | 
 |    ------------ | 
 |    -- Delete -- | 
 |    ------------ | 
 |  | 
 |    procedure Delete (File : in out File_Type) is | 
 |    begin | 
 |       FIO.Delete (AP (File)); | 
 |    end Delete; | 
 |  | 
 |    ----------------- | 
 |    -- End_Of_File -- | 
 |    ----------------- | 
 |  | 
 |    function End_Of_File (File : File_Type) return Boolean is | 
 |    begin | 
 |       return DIO.End_Of_File (FP (File)); | 
 |    end End_Of_File; | 
 |  | 
 |    ---------- | 
 |    -- Form -- | 
 |    ---------- | 
 |  | 
 |    function Form (File : File_Type) return String is | 
 |    begin | 
 |       return FIO.Form (AP (File)); | 
 |    end Form; | 
 |  | 
 |    ----------- | 
 |    -- Index -- | 
 |    ----------- | 
 |  | 
 |    function Index (File : File_Type) return Positive_Count is | 
 |    begin | 
 |       return Positive_Count (DIO.Index (FP (File))); | 
 |    end Index; | 
 |  | 
 |    ------------- | 
 |    -- Is_Open -- | 
 |    ------------- | 
 |  | 
 |    function Is_Open (File : File_Type) return Boolean is | 
 |    begin | 
 |       return FIO.Is_Open (AP (File)); | 
 |    end Is_Open; | 
 |  | 
 |    ---------- | 
 |    -- Mode -- | 
 |    ---------- | 
 |  | 
 |    function Mode (File : File_Type) return File_Mode is | 
 |    begin | 
 |       return To_DIO (FIO.Mode (AP (File))); | 
 |    end Mode; | 
 |  | 
 |    ---------- | 
 |    -- Name -- | 
 |    ---------- | 
 |  | 
 |    function Name (File : File_Type) return String is | 
 |    begin | 
 |       return FIO.Name (AP (File)); | 
 |    end Name; | 
 |  | 
 |    ---------- | 
 |    -- Open -- | 
 |    ---------- | 
 |  | 
 |    procedure Open | 
 |      (File : in out File_Type; | 
 |       Mode : File_Mode; | 
 |       Name : String; | 
 |       Form : String := "") | 
 |    is | 
 |    begin | 
 |       DIO.Open (FP (File), To_FCB (Mode), Name, Form); | 
 |       File.Bytes := Bytes; | 
 |    end Open; | 
 |  | 
 |    ---------- | 
 |    -- Read -- | 
 |    ---------- | 
 |  | 
 |    procedure Read | 
 |      (File : File_Type; | 
 |       Item : out Element_Type; | 
 |       From : Positive_Count) | 
 |    is | 
 |    begin | 
 |       --  For a non-constrained variant record type, we read into an | 
 |       --  intermediate buffer, since we may have the case of discriminated | 
 |       --  records where a discriminant check is required, and we may need | 
 |       --  to assign only part of the record buffer originally written. | 
 |  | 
 |       --  Note: we have to turn warnings on/off because this use of | 
 |       --  the Constrained attribute is an obsolescent feature. | 
 |  | 
 |       pragma Warnings (Off); | 
 |       if not Element_Type'Constrained then | 
 |          pragma Warnings (On); | 
 |  | 
 |          declare | 
 |             Buf : Element_Type; | 
 |  | 
 |          begin | 
 |             DIO.Read (FP (File), Buf'Address, Bytes, DPCount (From)); | 
 |             Item := Buf; | 
 |          end; | 
 |  | 
 |       --  In the normal case, we can read straight into the buffer | 
 |  | 
 |       else | 
 |          DIO.Read (FP (File), Item'Address, Bytes, DPCount (From)); | 
 |       end if; | 
 |    end Read; | 
 |  | 
 |    procedure Read (File : File_Type; Item : out Element_Type) is | 
 |    begin | 
 |       --  Same processing for unconstrained case as above | 
 |  | 
 |       --  Note: we have to turn warnings on/off because this use of | 
 |       --  the Constrained attribute is an obsolescent feature. | 
 |  | 
 |       pragma Warnings (Off); | 
 |       if not Element_Type'Constrained then | 
 |          pragma Warnings (On); | 
 |  | 
 |          declare | 
 |             Buf : Element_Type; | 
 |  | 
 |          begin | 
 |             DIO.Read (FP (File), Buf'Address, Bytes); | 
 |             Item := Buf; | 
 |          end; | 
 |  | 
 |       else | 
 |          DIO.Read (FP (File), Item'Address, Bytes); | 
 |       end if; | 
 |    end Read; | 
 |  | 
 |    ----------- | 
 |    -- Reset -- | 
 |    ----------- | 
 |  | 
 |    procedure Reset (File : in out File_Type; Mode : File_Mode) is | 
 |    begin | 
 |       DIO.Reset (FP (File), To_FCB (Mode)); | 
 |    end Reset; | 
 |  | 
 |    procedure Reset (File : in out File_Type) is | 
 |    begin | 
 |       DIO.Reset (FP (File)); | 
 |    end Reset; | 
 |  | 
 |    --------------- | 
 |    -- Set_Index -- | 
 |    --------------- | 
 |  | 
 |    procedure Set_Index (File : File_Type; To : Positive_Count) is | 
 |    begin | 
 |       DIO.Set_Index (FP (File), DPCount (To)); | 
 |    end Set_Index; | 
 |  | 
 |    ---------- | 
 |    -- Size -- | 
 |    ---------- | 
 |  | 
 |    function Size (File : File_Type) return Count is | 
 |    begin | 
 |       return Count (DIO.Size (FP (File))); | 
 |    end Size; | 
 |  | 
 |    ----------- | 
 |    -- Write -- | 
 |    ----------- | 
 |  | 
 |    procedure Write | 
 |      (File : File_Type; | 
 |       Item : Element_Type; | 
 |       To   : Positive_Count) | 
 |    is | 
 |    begin | 
 |       DIO.Set_Index (FP (File), DPCount (To)); | 
 |       DIO.Write (FP (File), Item'Address, Item'Size / SU, Zeroes); | 
 |    end Write; | 
 |  | 
 |    procedure Write (File : File_Type; Item : Element_Type) is | 
 |    begin | 
 |       DIO.Write (FP (File), Item'Address, Item'Size / SU, Zeroes); | 
 |    end Write; | 
 |  | 
 | end Ada.Direct_IO; |