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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 gzip format). | |
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 | \func{}{wxZlibInputStream}{\param{wxInputStream*}{ stream}, \param{int}{ flags = wxZLIB\_AUTO}} | |
34 | ||
35 | If the parent stream is passed as a pointer then the new filter stream | |
36 | takes ownership of it. If it is passed by reference then it does not. | |
37 | ||
38 | The {\it flags} wxZLIB\_ZLIB and wxZLIB\_GZIP specify whether the input data | |
39 | is in zlib or gzip format. If wxZLIB\_AUTO is used, then zlib will | |
40 | autodetect the stream type, this is the default. | |
41 | ||
42 | If {\it flags} is wxZLIB\_NO\_HEADER, then the data is assumed to be a raw | |
43 | deflate stream without either zlib or gzip headers. This is a lower level | |
44 | mode, which is not usually used directly. It can be used to read a raw | |
45 | deflate stream embedded in a higher level protocol. | |
46 | ||
47 | %if WXWIN_COMPATIBILITY_2_4 | |
48 | This version is not by default compatible with the output produced by | |
49 | the version of {\it wxZlibOutputStream} in wxWidgets 2.4.x. However, | |
50 | there is a compatibility mode, which is switched on by passing | |
51 | wxZLIB\_24COMPATIBLE for flags. Note that in when operating in compatibility | |
52 | mode error checking is very much reduced. | |
53 | %endif | |
54 | ||
55 | The following symbols can be use for the flags: | |
56 | ||
57 | \begin{verbatim} | |
58 | // Flags | |
59 | enum { | |
60 | #if WXWIN_COMPATIBILITY_2_4 | |
61 | wxZLIB_24COMPATIBLE = 4, // read v2.4.x data without error | |
62 | #endif | |
63 | wxZLIB_NO_HEADER = 0, // raw deflate stream, no header or checksum | |
64 | wxZLIB_ZLIB = 1, // zlib header and checksum | |
65 | wxZLIB_GZIP = 2, // gzip header and checksum, requires zlib 1.2.1+ | |
66 | wxZLIB_AUTO = 3 // autodetect header zlib or gzip | |
67 | }; | |
68 | \end{verbatim} | |
69 | ||
70 | \membersection{wxZlibInputStream::CanHandleGZip}\label{wxzlibinputstreamcanhandlegzip} | |
71 | ||
72 | \func{static bool}{CanHandleGZip}{\void} | |
73 | ||
74 | Returns true if zlib library in use can handle gzip compressed data. | |
75 | ||
76 | % ----------------------------------------------------------------------------- | |
77 | % wxZlibOutputStream | |
78 | % ----------------------------------------------------------------------------- | |
79 | \section{\class{wxZlibOutputStream}}\label{wxzliboutputstream} | |
80 | ||
81 | This stream compresses all data written to it. The compressed output can be | |
82 | in zlib or gzip format. | |
83 | Note that writing the gzip format requires zlib version 1.2.1 or greater | |
84 | (the builtin version does support gzip format). | |
85 | ||
86 | The stream is not seekable, \helpref{SeekO()}{wxoutputstreamseeko} returns | |
87 | {\it wxInvalidOffset}. | |
88 | ||
89 | \wxheading{Derived from} | |
90 | ||
91 | \helpref{wxFilterOutputStream}{wxfilteroutputstream} | |
92 | ||
93 | \wxheading{Include files} | |
94 | ||
95 | <wx/zstream.h> | |
96 | ||
97 | \wxheading{See also} | |
98 | ||
99 | \helpref{wxOutputStream}{wxoutputstream}, | |
100 | \helpref{wxZlibInputStream}{wxzlibinputstream} | |
101 | ||
102 | ||
103 | \latexignore{\rtfignore{\wxheading{Members}}} | |
104 | ||
105 | \membersection{wxZlibOutputStream::wxZlibOutputStream}\label{wxzliboutputstreamwxzliboutputstream} | |
106 | ||
107 | \func{}{wxZlibOutputStream}{\param{wxOutputStream\&}{ stream}, \param{int}{ level = -1}, \param{int}{ flags = wxZLIB\_ZLIB}} | |
108 | ||
109 | \func{}{wxZlibOutputStream}{\param{wxOutputStream*}{ stream}, \param{int}{ level = -1}, \param{int}{ flags = wxZLIB\_ZLIB}} | |
110 | ||
111 | Creates a new write-only compressed stream. {\it level} means level of | |
112 | compression. It is number between 0 and 9 (including these values) where | |
113 | 0 means no compression and 9 best but slowest compression. -1 is default | |
114 | value (currently equivalent to 6). | |
115 | ||
116 | If the parent stream is passed as a pointer then the new filter stream | |
117 | takes ownership of it. If it is passed by reference then it does not. | |
118 | ||
119 | The {\it flags} wxZLIB\_ZLIB and wxZLIB\_GZIP specify whether the output data | |
120 | will be in zlib or gzip format. wxZLIB\_ZLIB is the default. | |
121 | ||
122 | If {\it flags} is wxZLIB\_NO\_HEADER, then a raw deflate stream is output | |
123 | without either zlib or gzip headers. This is a lower level | |
124 | mode, which is not usually used directly. It can be used to embed a raw | |
125 | deflate stream in a higher level protocol. | |
126 | ||
127 | The following symbols can be use for the compression level and flags: | |
128 | ||
129 | \begin{verbatim} | |
130 | // Compression level | |
131 | enum { | |
132 | wxZ_DEFAULT_COMPRESSION = -1, | |
133 | wxZ_NO_COMPRESSION = 0, | |
134 | wxZ_BEST_SPEED = 1, | |
135 | wxZ_BEST_COMPRESSION = 9 | |
136 | }; | |
137 | ||
138 | // Flags | |
139 | enum { | |
140 | wxZLIB_NO_HEADER = 0, // raw deflate stream, no header or checksum | |
141 | wxZLIB_ZLIB = 1, // zlib header and checksum | |
142 | wxZLIB_GZIP = 2 // gzip header and checksum, requires zlib 1.2.1+ | |
143 | }; | |
144 | \end{verbatim} | |
145 | ||
146 | \membersection{wxZlibOutputStream::CanHandleGZip}\label{wxoutputstreamcanhandlegzip} | |
147 | ||
148 | \func{static bool}{CanHandleGZip}{\void} | |
149 | ||
150 | Returns true if zlib library in use can handle gzip compressed data. | |
151 |