115 lines
		
	
	
		
			4.2 KiB
		
	
	
	
		
			Ada
		
	
	
	
	
	
		
		
			
		
	
	
			115 lines
		
	
	
		
			4.2 KiB
		
	
	
	
		
			Ada
		
	
	
	
	
	
|   | ----------------------------------------------------------------
 | ||
|  | --  ZLib for Ada thick binding.                               --
 | ||
|  | --                                                            --
 | ||
|  | --  Copyright (C) 2002-2003 Dmitriy Anisimkov                 --
 | ||
|  | --                                                            --
 | ||
|  | --  Open source license information is in the zlib.ads file.  --
 | ||
|  | ----------------------------------------------------------------
 | ||
|  | 
 | ||
|  | --  $Id: zlib-streams.ads,v 1.12 2004/05/31 10:53:40 vagul Exp $
 | ||
|  | 
 | ||
|  | package ZLib.Streams is | ||
|  | 
 | ||
|  |    type Stream_Mode is (In_Stream, Out_Stream, Duplex); | ||
|  | 
 | ||
|  |    type Stream_Access is access all Ada.Streams.Root_Stream_Type'Class; | ||
|  | 
 | ||
|  |    type Stream_Type is | ||
|  |       new Ada.Streams.Root_Stream_Type with private; | ||
|  | 
 | ||
|  |    procedure Read | ||
|  |      (Stream : in out Stream_Type; | ||
|  |       Item   :    out Ada.Streams.Stream_Element_Array; | ||
|  |       Last   :    out Ada.Streams.Stream_Element_Offset); | ||
|  | 
 | ||
|  |    procedure Write | ||
|  |      (Stream : in out Stream_Type; | ||
|  |       Item   : in     Ada.Streams.Stream_Element_Array); | ||
|  | 
 | ||
|  |    procedure Flush | ||
|  |      (Stream : in out Stream_Type; | ||
|  |       Mode   : in     Flush_Mode := Sync_Flush); | ||
|  |    --  Flush the written data to the back stream,
 | ||
|  |    --  all data placed to the compressor is flushing to the Back stream.
 | ||
|  |    --  Should not be used until necessary, because it is decreasing
 | ||
|  |    --  compression.
 | ||
|  | 
 | ||
|  |    function Read_Total_In (Stream : in Stream_Type) return Count; | ||
|  |    pragma Inline (Read_Total_In); | ||
|  |    --  Return total number of bytes read from back stream so far.
 | ||
|  | 
 | ||
|  |    function Read_Total_Out (Stream : in Stream_Type) return Count; | ||
|  |    pragma Inline (Read_Total_Out); | ||
|  |    --  Return total number of bytes read so far.
 | ||
|  | 
 | ||
|  |    function Write_Total_In (Stream : in Stream_Type) return Count; | ||
|  |    pragma Inline (Write_Total_In); | ||
|  |    --  Return total number of bytes written so far.
 | ||
|  | 
 | ||
|  |    function Write_Total_Out (Stream : in Stream_Type) return Count; | ||
|  |    pragma Inline (Write_Total_Out); | ||
|  |    --  Return total number of bytes written to the back stream.
 | ||
|  | 
 | ||
|  |    procedure Create | ||
|  |      (Stream            :    out Stream_Type; | ||
|  |       Mode              : in     Stream_Mode; | ||
|  |       Back              : in     Stream_Access; | ||
|  |       Back_Compressed   : in     Boolean; | ||
|  |       Level             : in     Compression_Level := Default_Compression; | ||
|  |       Strategy          : in     Strategy_Type     := Default_Strategy; | ||
|  |       Header            : in     Header_Type       := Default; | ||
|  |       Read_Buffer_Size  : in     Ada.Streams.Stream_Element_Offset | ||
|  |                                     := Default_Buffer_Size; | ||
|  |       Write_Buffer_Size : in     Ada.Streams.Stream_Element_Offset | ||
|  |                                     := Default_Buffer_Size); | ||
|  |    --  Create the Comression/Decompression stream.
 | ||
|  |    --  If mode is In_Stream then Write operation is disabled.
 | ||
|  |    --  If mode is Out_Stream then Read operation is disabled.
 | ||
|  | 
 | ||
|  |    --  If Back_Compressed is true then
 | ||
|  |    --  Data written to the Stream is compressing to the Back stream
 | ||
|  |    --  and data read from the Stream is decompressed data from the Back stream.
 | ||
|  | 
 | ||
|  |    --  If Back_Compressed is false then
 | ||
|  |    --  Data written to the Stream is decompressing to the Back stream
 | ||
|  |    --  and data read from the Stream is compressed data from the Back stream.
 | ||
|  | 
 | ||
|  |    --  !!! When the Need_Header is False ZLib-Ada is using undocumented
 | ||
|  |    --  ZLib 1.1.4 functionality to do not create/wait for ZLib headers.
 | ||
|  | 
 | ||
|  |    function Is_Open (Stream : Stream_Type) return Boolean; | ||
|  | 
 | ||
|  |    procedure Close (Stream : in out Stream_Type); | ||
|  | 
 | ||
|  | private | ||
|  | 
 | ||
|  |    use Ada.Streams; | ||
|  | 
 | ||
|  |    type Buffer_Access is access all Stream_Element_Array; | ||
|  | 
 | ||
|  |    type Stream_Type | ||
|  |      is new Root_Stream_Type with | ||
|  |    record | ||
|  |       Mode       : Stream_Mode; | ||
|  | 
 | ||
|  |       Buffer     : Buffer_Access; | ||
|  |       Rest_First : Stream_Element_Offset; | ||
|  |       Rest_Last  : Stream_Element_Offset; | ||
|  |       --  Buffer for Read operation.
 | ||
|  |       --  We need to have this buffer in the record
 | ||
|  |       --  because not all read data from back stream
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|  |       --  could be processed during the read operation.
 | ||
|  | 
 | ||
|  |       Buffer_Size : Stream_Element_Offset; | ||
|  |       --  Buffer size for write operation.
 | ||
|  |       --  We do not need to have this buffer
 | ||
|  |       --  in the record because all data could be
 | ||
|  |       --  processed in the write operation.
 | ||
|  | 
 | ||
|  |       Back       : Stream_Access; | ||
|  |       Reader     : Filter_Type; | ||
|  |       Writer     : Filter_Type; | ||
|  |    end record; | ||
|  | 
 | ||
|  | end ZLib.Streams; |