| 1 | ---------------------------------------------------------------- |
| 2 | -- ZLib for Ada thick binding. -- |
| 3 | -- -- |
| 4 | -- Copyright (C) 2002-2003 Dmitriy Anisimkov -- |
| 5 | -- -- |
| 6 | -- Open source license information is in the zlib.ads file. -- |
| 7 | ---------------------------------------------------------------- |
| 8 | |
| 9 | -- $Id: zlib-streams.ads,v 1.12 2004/05/31 10:53:40 vagul Exp $ |
| 10 | |
| 11 | package ZLib.Streams is |
| 12 | |
| 13 | type Stream_Mode is (In_Stream, Out_Stream, Duplex); |
| 14 | |
| 15 | type Stream_Access is access all Ada.Streams.Root_Stream_Type'Class; |
| 16 | |
| 17 | type Stream_Type is |
| 18 | new Ada.Streams.Root_Stream_Type with private; |
| 19 | |
| 20 | procedure Read |
| 21 | (Stream : in out Stream_Type; |
| 22 | Item : out Ada.Streams.Stream_Element_Array; |
| 23 | Last : out Ada.Streams.Stream_Element_Offset); |
| 24 | |
| 25 | procedure Write |
| 26 | (Stream : in out Stream_Type; |
| 27 | Item : in Ada.Streams.Stream_Element_Array); |
| 28 | |
| 29 | procedure Flush |
| 30 | (Stream : in out Stream_Type; |
| 31 | Mode : in Flush_Mode := Sync_Flush); |
| 32 | -- Flush the written data to the back stream, |
| 33 | -- all data placed to the compressor is flushing to the Back stream. |
| 34 | -- Should not be used until necessary, because it is decreasing |
| 35 | -- compression. |
| 36 | |
| 37 | function Read_Total_In (Stream : in Stream_Type) return Count; |
| 38 | pragma Inline (Read_Total_In); |
| 39 | -- Return total number of bytes read from back stream so far. |
| 40 | |
| 41 | function Read_Total_Out (Stream : in Stream_Type) return Count; |
| 42 | pragma Inline (Read_Total_Out); |
| 43 | -- Return total number of bytes read so far. |
| 44 | |
| 45 | function Write_Total_In (Stream : in Stream_Type) return Count; |
| 46 | pragma Inline (Write_Total_In); |
| 47 | -- Return total number of bytes written so far. |
| 48 | |
| 49 | function Write_Total_Out (Stream : in Stream_Type) return Count; |
| 50 | pragma Inline (Write_Total_Out); |
| 51 | -- Return total number of bytes written to the back stream. |
| 52 | |
| 53 | procedure Create |
| 54 | (Stream : out Stream_Type; |
| 55 | Mode : in Stream_Mode; |
| 56 | Back : in Stream_Access; |
| 57 | Back_Compressed : in Boolean; |
| 58 | Level : in Compression_Level := Default_Compression; |
| 59 | Strategy : in Strategy_Type := Default_Strategy; |
| 60 | Header : in Header_Type := Default; |
| 61 | Read_Buffer_Size : in Ada.Streams.Stream_Element_Offset |
| 62 | := Default_Buffer_Size; |
| 63 | Write_Buffer_Size : in Ada.Streams.Stream_Element_Offset |
| 64 | := Default_Buffer_Size); |
| 65 | -- Create the Compression/Decompression stream. |
| 66 | -- If mode is In_Stream then Write operation is disabled. |
| 67 | -- If mode is Out_Stream then Read operation is disabled. |
| 68 | |
| 69 | -- If Back_Compressed is true then |
| 70 | -- Data written to the Stream is compressing to the Back stream |
| 71 | -- and data read from the Stream is decompressed data from the Back stream. |
| 72 | |
| 73 | -- If Back_Compressed is false then |
| 74 | -- Data written to the Stream is decompressing to the Back stream |
| 75 | -- and data read from the Stream is compressed data from the Back stream. |
| 76 | |
| 77 | -- !!! When the Need_Header is False ZLib-Ada is using undocumented |
| 78 | -- ZLib 1.1.4 functionality to do not create/wait for ZLib headers. |
| 79 | |
| 80 | function Is_Open (Stream : Stream_Type) return Boolean; |
| 81 | |
| 82 | procedure Close (Stream : in out Stream_Type); |
| 83 | |
| 84 | private |
| 85 | |
| 86 | use Ada.Streams; |
| 87 | |
| 88 | type Buffer_Access is access all Stream_Element_Array; |
| 89 | |
| 90 | type Stream_Type |
| 91 | is new Root_Stream_Type with |
| 92 | record |
| 93 | Mode : Stream_Mode; |
| 94 | |
| 95 | Buffer : Buffer_Access; |
| 96 | Rest_First : Stream_Element_Offset; |
| 97 | Rest_Last : Stream_Element_Offset; |
| 98 | -- Buffer for Read operation. |
| 99 | -- We need to have this buffer in the record |
| 100 | -- because not all read data from back stream |
| 101 | -- could be processed during the read operation. |
| 102 | |
| 103 | Buffer_Size : Stream_Element_Offset; |
| 104 | -- Buffer size for write operation. |
| 105 | -- We do not need to have this buffer |
| 106 | -- in the record because all data could be |
| 107 | -- processed in the write operation. |
| 108 | |
| 109 | Back : Stream_Access; |
| 110 | Reader : Filter_Type; |
| 111 | Writer : Filter_Type; |
| 112 | end record; |
| 113 | |
| 114 | end ZLib.Streams; |