interface/zstream.h

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        zstream.h
   3 // Purpose:     documentation for wxZlibOutputStream class
   4 // Author:      wxWidgets team
   5 // RCS-ID:      $Id$
   6 // Licence:     wxWindows license
   7 /////////////////////////////////////////////////////////////////////////////
   8
   9 /**
  10     @class wxZlibOutputStream
  11     @wxheader{zstream.h}
  12
  13     This stream compresses all data written to it. The compressed output can be
  14     in zlib or gzip format.
  15     Note that writing the gzip format requires zlib version 1.2.1 or greater
  16     (the builtin version does support gzip format).
  17
  18     The stream is not seekable, wxOutputStream::SeekO returns
  19      @e wxInvalidOffset.
  20
  21     @library{wxbase}
  22     @category{streams}
  23
  24     @seealso
  25     wxOutputStream, wxZlibInputStream
  26 */
  27 class wxZlibOutputStream : public wxFilterOutputStream
  28 {
  29 public:
  30     //@{
  31     /**
  32         Creates a new write-only compressed stream. @e level means level of
  33         compression. It is number between 0 and 9 (including these values) where
  34         0 means no compression and 9 best but slowest compression. -1 is default
  35         value (currently equivalent to 6).
  36
  37         If the parent stream is passed as a pointer then the new filter stream
  38         takes ownership of it. If it is passed by reference then it does not.
  39
  40         The @e flags wxZLIB_ZLIB and wxZLIB_GZIP specify whether the output data
  41         will be in zlib or gzip format. wxZLIB_ZLIB is the default.
  42
  43         If @e flags is wxZLIB_NO_HEADER, then a raw deflate stream is output
  44         without either zlib or gzip headers. This is a lower level
  45         mode, which is not usually used directly. It can be used to embed a raw
  46         deflate stream in a higher level protocol.
  47
  48         The following symbols can be use for the compression level and flags:
  49     */
  50     wxZlibOutputStream(wxOutputStream& stream, int level = -1,
  51                        int flags = wxZLIB_ZLIB);
  52     wxZlibOutputStream(wxOutputStream* stream, int level = -1,
  53                        int flags = wxZLIB_ZLIB);
  54     //@}
  55
  56     /**
  57         Returns @true if zlib library in use can handle gzip compressed data.
  58     */
  59     static bool CanHandleGZip();
  60 };
  61
  62
  63 /**
  64     @class wxZlibInputStream
  65     @wxheader{zstream.h}
  66
  67     This filter stream decompresses a stream that is in zlib or gzip format.
  68     Note that reading the gzip format requires zlib version 1.2.1 or greater,
  69     (the builtin version does support gzip format).
  70
  71     The stream is not seekable, wxInputStream::SeekI returns
  72      @e wxInvalidOffset. Also wxStreamBase::GetSize is
  73     not supported, it always returns 0.
  74
  75     @library{wxbase}
  76     @category{streams}
  77
  78     @seealso
  79     wxInputStream, wxZlibOutputStream.
  80 */
  81 class wxZlibInputStream : public wxFilterInputStream
  82 {
  83 public:
  84     //@{
  85     /**
  86         If the parent stream is passed as a pointer then the new filter stream
  87         takes ownership of it. If it is passed by reference then it does not.
  88
  89         The @e flags wxZLIB_ZLIB and wxZLIB_GZIP specify whether the input data
  90         is in zlib or gzip format. If wxZLIB_AUTO is used, then zlib will
  91         autodetect the stream type, this is the default.
  92
  93         If @e flags is wxZLIB_NO_HEADER, then the data is assumed to be a raw
  94         deflate stream without either zlib or gzip headers. This is a lower level
  95         mode, which is not usually used directly. It can be used to read a raw
  96         deflate stream embedded in a higher level protocol.
  97
  98         This version is not by default compatible with the output produced by
  99         the version of @e wxZlibOutputStream in wxWidgets 2.4.x. However,
 100         there is a compatibility mode, which is switched on by passing
 101         wxZLIB_24COMPATIBLE for flags. Note that in when operating in compatibility
 102         mode error checking is very much reduced.
 103         The following symbols can be use for the flags:
 104     */
 105     wxZlibInputStream(wxInputStream& stream, int flags = wxZLIB_AUTO);
 106     wxZlibInputStream(wxInputStream* stream,
 107                       int flags = wxZLIB_AUTO);
 108     //@}
 109
 110     /**
 111         Returns @true if zlib library in use can handle gzip compressed data.
 112     */
 113     static bool CanHandleGZip();
 114 };