interface/wx/zstream.h

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        zstream.h
   3 // Purpose:     interface of wxZlibOutputStream
   4 // Author:      wxWidgets team
   5 // RCS-ID:      $Id$
   6 // Licence:     wxWindows license
   7 /////////////////////////////////////////////////////////////////////////////
   8
   9 /**
  10     @class wxZlibOutputStream
  11
  12     This stream compresses all data written to it. The compressed output can be
  13     in zlib or gzip format.
  14     Note that writing the gzip format requires zlib version 1.2.1 or greater
  15     (the builtin version does support gzip format).
  16
  17     The stream is not seekable, wxOutputStream::SeekO returns
  18      @e wxInvalidOffset.
  19
  20     @library{wxbase}
  21     @category{streams}
  22
  23     @see wxOutputStream, wxZlibInputStream
  24 */
  25 class wxZlibOutputStream : public wxFilterOutputStream
  26 {
  27 public:
  28     //@{
  29     /**
  30         Creates a new write-only compressed stream. @a level means level of
  31         compression. It is number between 0 and 9 (including these values) where
  32         0 means no compression and 9 best but slowest compression. -1 is default
  33         value (currently equivalent to 6).
  34         If the parent stream is passed as a pointer then the new filter stream
  35         takes ownership of it. If it is passed by reference then it does not.
  36         The @a flags wxZLIB_ZLIB and wxZLIB_GZIP specify whether the output data
  37         will be in zlib or gzip format. wxZLIB_ZLIB is the default.
  38         If @a flags is wxZLIB_NO_HEADER, then a raw deflate stream is output
  39         without either zlib or gzip headers. This is a lower level
  40         mode, which is not usually used directly. It can be used to embed a raw
  41         deflate stream in a higher level protocol.
  42         The following symbols can be use for the compression level and flags:
  43     */
  44     wxZlibOutputStream(wxOutputStream& stream, int level = -1,
  45                        int flags = wxZLIB_ZLIB);
  46     wxZlibOutputStream(wxOutputStream* stream, int level = -1,
  47                        int flags = wxZLIB_ZLIB);
  48     //@}
  49
  50     /**
  51         Returns @true if zlib library in use can handle gzip compressed data.
  52     */
  53     static bool CanHandleGZip();
  54 };
  55
  56
  57
  58 /**
  59     @class wxZlibInputStream
  60
  61     This filter stream decompresses a stream that is in zlib or gzip format.
  62     Note that reading the gzip format requires zlib version 1.2.1 or greater,
  63     (the builtin version does support gzip format).
  64
  65     The stream is not seekable, wxInputStream::SeekI returns
  66      @e wxInvalidOffset. Also wxStreamBase::GetSize is
  67     not supported, it always returns 0.
  68
  69     @library{wxbase}
  70     @category{streams}
  71
  72     @see wxInputStream, wxZlibOutputStream.
  73 */
  74 class wxZlibInputStream : public wxFilterInputStream
  75 {
  76 public:
  77     //@{
  78     /**
  79         If the parent stream is passed as a pointer then the new filter stream
  80         takes ownership of it. If it is passed by reference then it does not.
  81         The @a flags wxZLIB_ZLIB and wxZLIB_GZIP specify whether the input data
  82         is in zlib or gzip format. If wxZLIB_AUTO is used, then zlib will
  83         autodetect the stream type, this is the default.
  84         If @a flags is wxZLIB_NO_HEADER, then the data is assumed to be a raw
  85         deflate stream without either zlib or gzip headers. This is a lower level
  86         mode, which is not usually used directly. It can be used to read a raw
  87         deflate stream embedded in a higher level protocol.
  88         This version is not by default compatible with the output produced by
  89         the version of @e wxZlibOutputStream in wxWidgets 2.4.x. However,
  90         there is a compatibility mode, which is switched on by passing
  91         wxZLIB_24COMPATIBLE for flags. Note that in when operating in compatibility
  92         mode error checking is very much reduced.
  93         The following symbols can be use for the flags:
  94     */
  95     wxZlibInputStream(wxInputStream& stream, int flags = wxZLIB_AUTO);
  96     wxZlibInputStream(wxInputStream* stream,
  97                       int flags = wxZLIB_AUTO);
  98     //@}
  99
 100     /**
 101         Returns @true if zlib library in use can handle gzip compressed data.
 102     */
 103     static bool CanHandleGZip();
 104 };
 105