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------------------------------------------------------------------------------
-- --
-- GNAT RUNTIME COMPONENTS --
-- --
-- A D A . S T R E A M S . S T R E A M _ I O --
-- --
-- B o d y --
-- --
-- $Revision: 1.13 $ --
-- --
-- Copyright (c) 1992,1993,1994,1995 NYU, All Rights Reserved --
-- --
-- The GNAT library is free software; you can redistribute it and/or modify --
-- it under terms of the GNU Library General Public License as published by --
-- the Free Software Foundation; either version 2, or (at your option) any --
-- later version. The GNAT library is distributed in the hope that it will --
-- be useful, but WITHOUT ANY WARRANTY; without even the implied warranty --
-- of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU --
-- Library General Public License for more details. You should have --
-- received a copy of the GNU Library General Public License along with --
-- the GNAT library; see the file COPYING.LIB. If not, write to the Free --
-- Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. --
-- --
------------------------------------------------------------------------------
with Interfaces.C_Streams; use Interfaces.C_Streams;
with System; use System;
with System.File_IO;
with System.Tasking_Soft_Links;
with Unchecked_Conversion;
with Unchecked_Deallocation;
package body Ada.Streams.Stream_IO is
package FIO renames System.File_IO;
subtype AP is FCB.AFCB_Ptr;
function To_FCB is new Unchecked_Conversion (File_Mode, FCB.File_Mode);
function To_SIO is new Unchecked_Conversion (FCB.File_Mode, File_Mode);
-----------------------
-- Local Subprograms --
-----------------------
procedure Set_Position (File : in File_Type);
-- Sets file position pointer according to value of current index
-------------------
-- AFCB_Allocate --
-------------------
function AFCB_Allocate (Control_Block : Stream_AFCB) return FCB.AFCB_Ptr is
begin
return new Stream_AFCB;
end AFCB_Allocate;
----------------
-- AFCB_Close --
----------------
-- No special processing required for closing Stream_IO file
procedure AFCB_Close (File : access Stream_AFCB) is
begin
null;
end AFCB_Close;
---------------
-- AFCB_Free --
---------------
procedure AFCB_Free (File : access Stream_AFCB) is
type FCB_Ptr is access all Stream_AFCB;
FT : FCB_Ptr := File;
procedure Free is new Unchecked_Deallocation (Stream_AFCB, FCB_Ptr);
begin
Free (FT);
end AFCB_Free;
-----------
-- 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 : in File_Mode := Out_File;
Name : in String := "";
Form : in String := "")
is
File_Control_Block : Stream_AFCB;
begin
FIO.Open (File_Ptr => AP (File),
Dummy_FCB => File_Control_Block,
Mode => To_FCB (Mode),
Name => Name,
Form => Form,
Amethod => 'S',
Creat => True,
Text => False);
File.Last_Op := Op_Write;
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 : in File_Type) return Boolean is
begin
FIO.Check_Read_Status (AP (File));
return Count (File.Index) > Size (File);
end End_Of_File;
-----------
-- Flush --
-----------
procedure Flush (File : in out File_Type) is
begin
FIO.Flush (AP (File));
end Flush;
----------
-- Form --
----------
function Form (File : in File_Type) return String is
begin
return FIO.Form (AP (File));
end Form;
-----------
-- Index --
-----------
function Index (File : in File_Type) return Positive_Count is
begin
FIO.Check_File_Open (AP (File));
return Count (File.Index);
end Index;
-------------
-- Is_Open --
-------------
function Is_Open (File : in File_Type) return Boolean is
begin
return FIO.Is_Open (AP (File));
end Is_Open;
----------
-- Mode --
----------
function Mode (File : in File_Type) return File_Mode is
begin
return To_SIO (FIO.Mode (AP (File)));
end Mode;
----------
-- Name --
----------
function Name (File : in File_Type) return String is
begin
return FIO.Name (AP (File));
end Name;
----------
-- Open --
----------
procedure Open
(File : in out File_Type;
Mode : in File_Mode;
Name : in String;
Form : in String := "")
is
File_Control_Block : Stream_AFCB;
begin
FIO.Open (File_Ptr => AP (File),
Dummy_FCB => File_Control_Block,
Mode => To_FCB (Mode),
Name => Name,
Form => Form,
Amethod => 'S',
Creat => False,
Text => False);
File.Last_Op := Op_Read;
end Open;
----------
-- Read --
----------
procedure Read
(File : in File_Type;
Item : out Stream_Element_Array;
Last : out Stream_Element_Offset;
From : in Positive_Count)
is
begin
Set_Index (File, From);
Read (File, Item, Last);
end Read;
procedure Read
(File : in File_Type;
Item : out Stream_Element_Array;
Last : out Stream_Element_Offset)
is
Nread : size_t;
begin
FIO.Check_Read_Status (AP (File));
-- If last operation was not a read, or if in file sharing mode,
-- then reset the physical pointer of the file to match the index
-- We lock out task access over the two operations in this case.
if File.Last_Op /= Op_Read
or else File.Shared_Status = FCB.Yes
then
if End_Of_File (File) then
raise End_Error;
end if;
System.Tasking_Soft_Links.Lock_Task;
Set_Position (File);
FIO.Read_Buf (AP (File), Item'Address, Item'Length, Nread);
System.Tasking_Soft_Links.Unlock_Task;
else
FIO.Read_Buf (AP (File), Item'Address, Item'Length, Nread);
end if;
File.Index := File.Index + Count (Nread);
Last := Item'First + Stream_Element_Offset (Nread) - 1;
File.Last_Op := Op_Read;
end Read;
-- This version of Read is the primitive operation on the underlying
-- Stream type, used when a Stream_IO file is treated as a Stream
procedure Read
(File : in out Stream_AFCB;
Item : out Ada.Streams.Stream_Element_Array;
Last : out Ada.Streams.Stream_Element_Offset)
is
begin
if File.Mode > FCB.Inout_File then
raise Mode_Error;
end if;
Last :=
Item'First +
Stream_Element_Offset
(fread (Item'Address, 1, Item'Length, File.Stream)) - 1;
if Last < Item'Last then
if ferror (File.Stream) /= 0 then
raise Device_Error;
end if;
end if;
end Read;
-----------
-- Reset --
-----------
procedure Reset (File : in out File_Type; Mode : in File_Mode) is
begin
FIO.Reset (AP (File), To_FCB (Mode));
File.Index := 1;
File.Last_Op := Op_Read;
end Reset;
procedure Reset (File : in out File_Type) is
begin
FIO.Reset (AP (File));
File.Index := 1;
File.Last_Op := Op_Read;
end Reset;
---------------
-- Set_Index --
---------------
procedure Set_Index (File : in File_Type; To : in Positive_Count) is
begin
FIO.Check_File_Open (AP (File));
File.Index := Count (To);
File.Last_Op := Op_Other;
end Set_Index;
--------------
-- Set_Mode --
--------------
procedure Set_Mode (File : in out File_Type; Mode : in File_Mode) is
begin
-- If we are switching from read to write, or vice versa, and
-- we are not already open in update mode, then reopen in update
-- mode now. Note that we can use Inout_File as the mode for the
-- call since File_IO handles all modes for all file types.
if ((File.Mode = FCB.In_File) /= (Mode = In_File))
and then File.Update_Mode
then
FIO.Reset (AP (File), FCB.Inout_File);
end if;
-- Set required mode and position to end of file if append mode
File.Mode := To_FCB (Mode);
FIO.Append_Set (AP (File));
File.Index := Count (ftell (File.Stream)) + 1;
File.Last_Op := Op_Other;
end Set_Mode;
------------------
-- Set_Position --
------------------
procedure Set_Position (File : in File_Type) is
begin
if fseek (File.Stream, long (File.Index) - 1, SEEK_SET) /= 0 then
raise Use_Error;
end if;
end Set_Position;
----------
-- Size --
----------
function Size (File : in File_Type) return Count is
begin
FIO.Check_File_Open (AP (File));
File.Last_Op := Op_Other;
if fseek (File.Stream, 0, SEEK_END) /= 0 then
raise Device_Error;
end if;
return Positive_Count (ftell (File.Stream));
end Size;
------------
-- Stream --
------------
function Stream (File : in File_Type) return Stream_Access is
begin
return Stream_Access (File);
end Stream;
-----------
-- Write --
-----------
procedure Write
(File : in File_Type;
Item : in Stream_Element_Array;
To : in Positive_Count)
is
begin
Set_Index (File, To);
Write (File, Item);
end Write;
procedure Write (File : in File_Type; Item : in Stream_Element_Array) is
begin
FIO.Check_Write_Status (AP (File));
-- If last operation was not a write, or if in file sharing mode,
-- then reset the physical pointer of the file to match the index
-- We lock out task access over the two operations in this case.
if File.Last_Op /= Op_Write
or else File.Shared_Status = FCB.Yes
then
System.Tasking_Soft_Links.Lock_Task;
Set_Position (File);
FIO.Write_Buf (AP (File), Item'Address, Item'Length);
System.Tasking_Soft_Links.Unlock_Task;
else
FIO.Write_Buf (AP (File), Item'Address, Item'Length);
end if;
File.Index := File.Index + Item'Length;
File.Last_Op := Op_Write;
end Write;
-- This version of Write is the primitive operation on the underlying
-- Stream type, used when a Stream_IO file is treated as a Stream
procedure Write
(File : in out Stream_AFCB;
Item : in Ada.Streams.Stream_Element_Array)
is
Siz : constant size_t := Item'Length;
begin
if File.Mode = FCB.In_File then
raise Mode_Error;
end if;
if fwrite (Item'Address, 1, Siz, File.Stream) /= Siz then
raise Device_Error;
end if;
end Write;
end Ada.Streams.Stream_IO;
