| 1 | % ----------------------------------------------------------------------------- |
| 2 | % wxZlibInputStream |
| 3 | % ----------------------------------------------------------------------------- |
| 4 | \section{\class{wxZlibInputStream}}\label{wxzlibinputstream} |
| 5 | |
| 6 | This filter stream decompresses a stream that is in zlib or gzip format. |
| 7 | Note that reading the gzip format requires zlib version 1.2.1 or greater, |
| 8 | (the builtin version does support gzips). |
| 9 | |
| 10 | The stream is not seekable, \helpref{SeekI()}{wxinputstreamseeki} returns |
| 11 | {\it wxInvalidOffset}. Also \helpref{GetSize()}{wxstreambasegetsize} is |
| 12 | not supported, it always returns $0$. |
| 13 | |
| 14 | \wxheading{Derived from} |
| 15 | |
| 16 | \helpref{wxFilterInputStream}{wxfilterinputstream} |
| 17 | |
| 18 | \wxheading{Include files} |
| 19 | |
| 20 | <wx/zstream.h> |
| 21 | |
| 22 | \wxheading{See also} |
| 23 | |
| 24 | \helpref{wxInputStream}{wxinputstream}, |
| 25 | \helpref{wxZlibOutputStream}{wxzliboutputstream}. |
| 26 | |
| 27 | \latexignore{\rtfignore{\wxheading{Members}}} |
| 28 | |
| 29 | \membersection{wxZlibInputStream::wxZlibInputStream}\label{wxzlibinputstreamwxzlibinputstream} |
| 30 | |
| 31 | \func{}{wxZlibInputStream}{\param{wxInputStream\&}{ stream}, \param{int}{ flags = wxZLIB\_AUTO}} |
| 32 | |
| 33 | The {\it flags} wxZLIB\_ZLIB and wxZLIB\_GZIP specify whether the input data |
| 34 | is in zlib or gzip format. If wxZLIB\_AUTO is used, then zlib will |
| 35 | autodetect the stream type, this is the default. |
| 36 | |
| 37 | If {\it flags} is wxZLIB\_NO\_HEADER, then the data is assumed to be a raw |
| 38 | deflate stream without either zlib or gzip headers. This is a lower level |
| 39 | mode, which is not usually used directly. It can be used to read a raw |
| 40 | deflate stream embedded in a higher level protocol. |
| 41 | |
| 42 | %if WXWIN_COMPATIBILITY_2_4 |
| 43 | This version is not by default compatible with the output produced by |
| 44 | the version of {\it wxZlibOutputStream} in wxWidgets 2.4.x. However, |
| 45 | there is a compatibilty mode, which is switched on by passing |
| 46 | wxZLIB\_24COMPATIBLE for flags. Note that in when operating in compatibilty |
| 47 | mode error checking is very much reduced. |
| 48 | %endif |
| 49 | |
| 50 | The following symbols can be use for the flags: |
| 51 | |
| 52 | \begin{verbatim} |
| 53 | // Flags |
| 54 | enum { |
| 55 | #if WXWIN_COMPATIBILITY_2_4 |
| 56 | wxZLIB_24COMPATIBLE = 4, // read v2.4.x data without error |
| 57 | #endif |
| 58 | wxZLIB_NO_HEADER = 0, // raw deflate stream, no header or checksum |
| 59 | wxZLIB_ZLIB = 1, // zlib header and checksum |
| 60 | wxZLIB_GZIP = 2, // gzip header and checksum, requires zlib 1.2.1+ |
| 61 | wxZLIB_AUTO = 3 // autodetect header zlib or gzip |
| 62 | }; |
| 63 | \end{verbatim} |
| 64 | |
| 65 | \membersection{wxZlibInputStream::CanHandleGZip}\label{wxzlibinputstreamcanhandlegzip} |
| 66 | |
| 67 | \func{static bool}{CanHandleGZip}{\void} |
| 68 | |
| 69 | Returns true if zlib library in use can handle gzip compressed data. |
| 70 | |
| 71 | % ----------------------------------------------------------------------------- |
| 72 | % wxZlibOutputStream |
| 73 | % ----------------------------------------------------------------------------- |
| 74 | \section{\class{wxZlibOutputStream}}\label{wxzliboutputstream} |
| 75 | |
| 76 | This stream compresses all data written to it. The compressed output can be |
| 77 | in zlib or gzip format. |
| 78 | Note that writing the gzip format requires zlib version 1.2.1 or greater |
| 79 | (the builtin version does support gzips). |
| 80 | |
| 81 | The stream is not seekable, \helpref{SeekO()}{wxoutputstreamseeko} returns |
| 82 | {\it wxInvalidOffset}. |
| 83 | |
| 84 | \wxheading{Derived from} |
| 85 | |
| 86 | \helpref{wxFilterOutputStream}{wxfilteroutputstream} |
| 87 | |
| 88 | \wxheading{Include files} |
| 89 | |
| 90 | <wx/zstream.h> |
| 91 | |
| 92 | \wxheading{See also} |
| 93 | |
| 94 | \helpref{wxOutputStream}{wxoutputstream}, |
| 95 | \helpref{wxZlibInputStream}{wxzlibinputstream} |
| 96 | |
| 97 | |
| 98 | \latexignore{\rtfignore{\wxheading{Members}}} |
| 99 | |
| 100 | \membersection{wxZlibOutputStream::wxZlibOutputStream}\label{wxzliboutputstreamwxzliboutputstream} |
| 101 | |
| 102 | \func{}{wxZlibOutputStream}{\param{wxOutputStream\&}{ stream}, \param{int}{ level = -1}, \param{int}{ flags = wxZLIB\_ZLIB}} |
| 103 | |
| 104 | Creates a new write-only compressed stream. {\it level} means level of |
| 105 | compression. It is number between 0 and 9 (including these values) where |
| 106 | 0 means no compression and 9 best but slowest compression. -1 is default |
| 107 | value (currently equivalent to 6). |
| 108 | |
| 109 | The {\it flags} wxZLIB\_ZLIB and wxZLIB\_GZIP specify whether the output data |
| 110 | will be in zlib or gzip format. wxZLIB\_ZLIB is the default. |
| 111 | |
| 112 | If {\it flags} is wxZLIB\_NO\_HEADER, then a raw deflate stream is output |
| 113 | without either zlib or gzip headers. This is a lower level |
| 114 | mode, which is not usually used directly. It can be used to embed a raw |
| 115 | deflate stream in a higher level protocol. |
| 116 | |
| 117 | The following symbols can be use for the compression level and flags: |
| 118 | |
| 119 | \begin{verbatim} |
| 120 | // Compression level |
| 121 | enum { |
| 122 | wxZ_DEFAULT_COMPRESSION = -1, |
| 123 | wxZ_NO_COMPRESSION = 0, |
| 124 | wxZ_BEST_SPEED = 1, |
| 125 | wxZ_BEST_COMPRESSION = 9 |
| 126 | }; |
| 127 | |
| 128 | // Flags |
| 129 | enum { |
| 130 | wxZLIB_NO_HEADER = 0, // raw deflate stream, no header or checksum |
| 131 | wxZLIB_ZLIB = 1, // zlib header and checksum |
| 132 | wxZLIB_GZIP = 2 // gzip header and checksum, requires zlib 1.2.1+ |
| 133 | }; |
| 134 | \end{verbatim} |
| 135 | |
| 136 | \membersection{wxZlibOutputStream::CanHandleGZip}\label{wxoutputstreamcanhandlegzip} |
| 137 | |
| 138 | \func{static bool}{CanHandleGZip}{\void} |
| 139 | |
| 140 | Returns true if zlib library in use can handle gzip compressed data. |
| 141 | |