------------------------------------------------------------------------------ -- -- -- GNAT RUN-TIME COMPONENTS -- -- -- -- A D A . S T R E A M S . S T R E A M _ I O -- -- -- -- S p e c -- -- -- -- -- -- Copyright (C) 1992-2001 Free Software Foundation, Inc. -- -- -- -- This specification is derived from the Ada Reference Manual for use with -- -- GNAT. The copyright notice above, and the license provisions that follow -- -- apply solely to the contents of the part following the private keyword. -- -- -- -- 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. -- -- -- ------------------------------------------------------------------------------ with Ada.IO_Exceptions; with System.File_Control_Block; package Ada.Streams.Stream_IO is type Stream_Access is access all Root_Stream_Type'Class; type File_Type is limited private; type File_Mode is (In_File, Out_File, Append_File); -- The following representation clause allows the use of unchecked -- conversion for rapid translation between the File_Mode type -- used in this package and System.File_IO. for File_Mode use (In_File => 0, -- System.FIle_IO.File_Mode'Pos (In_File) Out_File => 2, -- System.File_IO.File_Mode'Pos (Out_File) Append_File => 3); -- System.File_IO.File_Mode'Pos (Append_File) type Count is new Stream_Element_Offset range 0 .. Stream_Element_Offset'Last; subtype Positive_Count is Count range 1 .. Count'Last; -- Index into file, in stream elements --------------------- -- File Management -- --------------------- procedure Create (File : in out File_Type; Mode : in File_Mode := Out_File; Name : in String := ""; Form : in String := ""); procedure Open (File : in out File_Type; Mode : in File_Mode; Name : in String; Form : in String := ""); procedure Close (File : in out File_Type); procedure Delete (File : in out File_Type); procedure Reset (File : in out File_Type; Mode : in File_Mode); procedure Reset (File : in out File_Type); function Mode (File : in File_Type) return File_Mode; function Name (File : in File_Type) return String; function Form (File : in File_Type) return String; function Is_Open (File : in File_Type) return Boolean; function End_Of_File (File : in File_Type) return Boolean; function Stream (File : in File_Type) return Stream_Access; ----------------------------- -- Input-Output Operations -- ----------------------------- procedure Read (File : in File_Type; Item : out Stream_Element_Array; Last : out Stream_Element_Offset; From : in Positive_Count); procedure Read (File : in File_Type; Item : out Stream_Element_Array; Last : out Stream_Element_Offset); procedure Write (File : in File_Type; Item : in Stream_Element_Array; To : in Positive_Count); procedure Write (File : in File_Type; Item : in Stream_Element_Array); ---------------------------------------- -- Operations on Position within File -- ---------------------------------------- procedure Set_Index (File : in File_Type; To : in Positive_Count); function Index (File : in File_Type) return Positive_Count; function Size (File : in File_Type) return Count; procedure Set_Mode (File : in out File_Type; Mode : in File_Mode); -- Note: The parameter file is IN OUT in the RM, but this is clearly -- an oversight, and was intended to be IN, see AI95-00057. procedure Flush (File : File_Type); ---------------- -- Exceptions -- ---------------- Status_Error : exception renames IO_Exceptions.Status_Error; Mode_Error : exception renames IO_Exceptions.Mode_Error; Name_Error : exception renames IO_Exceptions.Name_Error; Use_Error : exception renames IO_Exceptions.Use_Error; Device_Error : exception renames IO_Exceptions.Device_Error; End_Error : exception renames IO_Exceptions.End_Error; Data_Error : exception renames IO_Exceptions.Data_Error; private package FCB renames System.File_Control_Block; ----------------------------- -- Stream_IO Control Block -- ----------------------------- type Operation is (Op_Read, Op_Write, Op_Other); -- Type used to record last operation (to optimize sequential operations) type Stream_AFCB is new FCB.AFCB with record Index : Count := 1; -- Current Index value File_Size : Stream_Element_Offset := -1; -- Cached value of File_Size, so that we do not keep recomputing it -- when not necessary (otherwise End_Of_File becomes gruesomely slow). -- A value of minus one means that there is no cached value. Last_Op : Operation := Op_Other; -- Last operation performed on file, used to avoid unnecessary -- repositioning between successive read or write operations. Update_Mode : Boolean := False; -- Set if the mode is changed from write to read or vice versa. -- Indicates that the file has been reopened in update mode. end record; type File_Type is access all Stream_AFCB; function AFCB_Allocate (Control_Block : Stream_AFCB) return FCB.AFCB_Ptr; procedure AFCB_Close (File : access Stream_AFCB); procedure AFCB_Free (File : access Stream_AFCB); procedure Read (File : in out Stream_AFCB; Item : out Ada.Streams.Stream_Element_Array; Last : out Ada.Streams.Stream_Element_Offset); -- Read operation used when Stream_IO file is treated directly as Stream procedure Write (File : in out Stream_AFCB; Item : in Ada.Streams.Stream_Element_Array); -- Write operation used when Stream_IO file is treated directly as Stream end Ada.Streams.Stream_IO;