Subversion Repositories openrisc_2011-10-31

------------------------------------------------------------------------------

--                                                                          --

--                         GNAT RUN-TIME COMPONENTS                         --

--                                                                          --

--                        A D A . D I R E C T _ I O                         --

--                                                                          --

--                                 B o d y                                  --

--                                                                          --

--          Copyright (C) 1992-2009, 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 3,  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.                                     --

--                                                                          --

-- As a special exception 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/>.                                          --

--                                                                          --

-- 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 Ada.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 Ada.Unchecked_Conversion (File_Mode, FCB.File_Mode);

   function To_DIO is new Ada.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)'Unrestricted_Access);

   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)'Unrestricted_Access);

   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;