// Name: zstream.h
// Purpose: interface of wxZlibOutputStream
// Author: wxWidgets team
-// RCS-ID: $Id$
-// Licence: wxWindows license
+// Licence: wxWindows licence
/////////////////////////////////////////////////////////////////////////////
+
+/// Compression level
+enum wxZlibCompressionLevels {
+ wxZ_DEFAULT_COMPRESSION = -1,
+ wxZ_NO_COMPRESSION = 0,
+ wxZ_BEST_SPEED = 1,
+ wxZ_BEST_COMPRESSION = 9
+};
+
+/// Flags
+enum wxZLibFlags {
+ wxZLIB_NO_HEADER = 0, //!< raw deflate stream, no header or checksum
+ wxZLIB_ZLIB = 1, //!< zlib header and checksum
+ wxZLIB_GZIP = 2, //!< gzip header and checksum, requires zlib 1.2.1+
+ wxZLIB_AUTO = 3 //!< autodetect header zlib or gzip
+};
+
+
/**
@class wxZlibOutputStream
- This stream compresses all data written to it. The compressed output can be
- in zlib or gzip format.
+ This stream compresses all data written to it.
+
+ The compressed output can be in zlib or gzip format.
Note that writing the gzip format requires zlib version 1.2.1 or greater
(the builtin version does support gzip format).
- The stream is not seekable, wxOutputStream::SeekO returns
- @e wxInvalidOffset.
+ The stream is not seekable, wxOutputStream::SeekO() returns
+ ::wxInvalidOffset.
@library{wxbase}
- @category{streams}
+ @category{archive,streams}
@see wxOutputStream, wxZlibInputStream
*/
public:
//@{
/**
- Creates a new write-only compressed stream. @a level means level of
- compression. It is number between 0 and 9 (including these values) where
- 0 means no compression and 9 best but slowest compression. -1 is default
- value (currently equivalent to 6).
+ Creates a new write-only compressed stream.
+
+ @a level means level of compression. It is number between 0 and 9
+ (including these values) where 0 means no compression and 9 best but
+ slowest compression. -1 is default value (currently equivalent to 6).
+
If the parent stream is passed as a pointer then the new filter stream
takes ownership of it. If it is passed by reference then it does not.
+
The @a flags wxZLIB_ZLIB and wxZLIB_GZIP specify whether the output data
will be in zlib or gzip format. wxZLIB_ZLIB is the default.
+
If @a flags is wxZLIB_NO_HEADER, then a raw deflate stream is output
- without either zlib or gzip headers. This is a lower level
- mode, which is not usually used directly. It can be used to embed a raw
- deflate stream in a higher level protocol.
- The following symbols can be use for the compression level and flags:
+ without either zlib or gzip headers. This is a lower level mode, which
+ is not usually used directly. It can be used to embed a raw deflate
+ stream in a higher level protocol.
+
+ The values of the ::wxZlibCompressionLevels and ::wxZLibFlags
+ enumerations can be used.
*/
wxZlibOutputStream(wxOutputStream& stream, int level = -1,
int flags = wxZLIB_ZLIB);
Returns @true if zlib library in use can handle gzip compressed data.
*/
static bool CanHandleGZip();
+
+ //@{
+ /**
+ Sets the dictionary to the specified chunk of data. This can improve
+ compression rate but note that the dictionary has to be the same when
+ you deflate the data as when you inflate the data, otherwise you
+ will inflate corrupted data.
+
+ Returns @true if the dictionary was successfully set.
+ */
+ bool SetDictionary(const char *data, const size_t datalen);
+ bool SetDictionary(const wxMemoryBuffer &buf);
+ //@}
};
Note that reading the gzip format requires zlib version 1.2.1 or greater,
(the builtin version does support gzip format).
- The stream is not seekable, wxInputStream::SeekI returns
- @e wxInvalidOffset. Also wxStreamBase::GetSize is
- not supported, it always returns 0.
+ The stream is not seekable, wxInputStream::SeekI returns ::wxInvalidOffset.
+ Also wxStreamBase::GetSize() is not supported, it always returns 0.
@library{wxbase}
- @category{streams}
+ @category{archive,streams}
@see wxInputStream, wxZlibOutputStream.
*/
/**
If the parent stream is passed as a pointer then the new filter stream
takes ownership of it. If it is passed by reference then it does not.
+
The @a flags wxZLIB_ZLIB and wxZLIB_GZIP specify whether the input data
is in zlib or gzip format. If wxZLIB_AUTO is used, then zlib will
autodetect the stream type, this is the default.
+
If @a flags is wxZLIB_NO_HEADER, then the data is assumed to be a raw
deflate stream without either zlib or gzip headers. This is a lower level
mode, which is not usually used directly. It can be used to read a raw
deflate stream embedded in a higher level protocol.
- This version is not by default compatible with the output produced by
- the version of @e wxZlibOutputStream in wxWidgets 2.4.x. However,
- there is a compatibility mode, which is switched on by passing
- wxZLIB_24COMPATIBLE for flags. Note that in when operating in compatibility
- mode error checking is very much reduced.
- The following symbols can be use for the flags:
+
+ The values of the ::wxZLibFlags enumeration can be used.
*/
wxZlibInputStream(wxInputStream& stream, int flags = wxZLIB_AUTO);
- wxZlibInputStream(wxInputStream* stream,
- int flags = wxZLIB_AUTO);
+ wxZlibInputStream(wxInputStream* stream, int flags = wxZLIB_AUTO);
//@}
/**
Returns @true if zlib library in use can handle gzip compressed data.
*/
static bool CanHandleGZip();
+
+ //@{
+ /**
+ Sets the dictionary to the specified chunk of data. This can improve
+ compression rate but note that the dictionary has to be the same when
+ you deflate the data as when you inflate the data, otherwise you
+ will inflate corrupted data.
+
+ Returns @true if the dictionary was successfully set.
+ */
+ bool SetDictionary(const char *data, const size_t datalen);
+ bool SetDictionary(const wxMemoryBuffer &buf);
+ //@}
};
projects / wxWidgets.git / blobdiff