Ogre::DeflateStream Class Reference

Stream which compresses / uncompresses data using the 'deflate' compression algorithm. More...

#include <OgreDeflate.h>

Inheritance diagram for Ogre::DeflateStream:

Public Types
enum	StreamType { Invalid = -1 , Deflate = 0 , ZLib = 1 , GZip = 2 }
	Requested stream type. More...
Public Types inherited from Ogre::DataStream
enum	AccessMode { READ = 1 , WRITE = 2 }

Public Member Functions
	DeflateStream (const DataStreamPtr &compressedStream, const String &tmpFileName="", size_t avail_in=0)
	Constructor for creating unnamed stream wrapping another stream.
	DeflateStream (const String &name, const DataStreamPtr &compressedStream, const String &tmpFileName="", size_t avail_in=0)
	Constructor for creating named stream wrapping another stream.
	DeflateStream (const String &name, const DataStreamPtr &compressedStream, StreamType streamType, const String &tmpFileName="", size_t avail_in=0)
	Constructor for creating named stream wrapping another stream.
	~DeflateStream ()
void	close (void) override
	Close the stream; this makes further operations invalid.
bool	eof (void) const override
	Returns true if the stream has reached the end.
bool	isCompressedStreamValid () const
	Returns whether the compressed stream is valid deflated data.
size_t	read (void *buf, size_t count) override
	Read the requisite number of bytes from the stream, stopping at the end of the file.
void	seek (size_t pos) override
	Repositions the read point to a specified byte.
void	skip (long count) override
	Skip a defined number of bytes.
size_t	tell (void) const override
	Returns the current byte offset from beginning.
size_t	write (const void *buf, size_t count) override
	Write the requisite number of bytes from the stream (only applicable to streams that are not read-only)
Public Member Functions inherited from Ogre::DataStream
	DataStream (const String &name, uint16 accessMode=READ)
	Constructor for creating named streams.
	DataStream (uint16 accessMode=READ)
	Constructor for creating unnamed streams.
virtual	~DataStream ()
uint16	getAccessMode () const
	Gets the access mode of the stream.
virtual String	getAsString (void)
	Returns a String containing the entire stream.
virtual String	getLine (bool trimAfter=true)
	Returns a String containing the next line of data, optionally trimmed for whitespace.
const String &	getName (void)
	Returns the name of the stream, if it has one.
virtual bool	isReadable () const
	Reports whether this stream is readable.
virtual bool	isWriteable () const
	Reports whether this stream is writeable.
template<typename T >
DataStream &	operator>> (T &val)
virtual size_t	readLine (char *buf, size_t maxCount, const String &delim="\n")
	Get a single line from the stream.
size_t	size (void) const
	Returns the total size of the data to be read from the stream, or 0 if this is indeterminate for this stream.
virtual size_t	skipLine (const String &delim="\n")
	Skip a single line from the stream.

Detailed Description

Stream which compresses / uncompresses data using the 'deflate' compression algorithm.

This stream is designed to wrap another stream for the actual source / destination of the compressed data, it has no concrete source / data itself. The idea is that you pass uncompressed data through this stream, and the underlying stream reads/writes compressed data to the final source.

Note

This is an alternative to using a compressed archive since it is able to compress & decompress regardless of the actual source of the stream. You should avoid using this with already compressed archives. Also note that this cannot be used as a read / write stream, only a read-only or write-only stream.

Member Enumeration Documentation

StreamType

enum Ogre::DeflateStream::StreamType

Requested stream type.

All are essentially the same deflate stream with varying wrapping. ZLib is used by default.

Enumerator
Invalid
Deflate	Unexpected stream type or uncompressed data.
ZLib	no header, no checksum, rfc1951
GZip	2 byte header, 4 byte footer with adler32 checksum, rfc1950

Constructor & Destructor Documentation

DeflateStream() [1/3]

Ogre::DeflateStream::DeflateStream	(	const DataStreamPtr &	compressedStream,
		const String &	tmpFileName = "",
		size_t	avail_in = 0
	)

Constructor for creating unnamed stream wrapping another stream.

Parameters

compressedStream	The stream that this stream will use when reading / writing compressed data. The access mode from this stream will be matched.
tmpFileName	Path/Filename to be used for temporary storage of incoming data
avail_in	Available data length to be uncompressed. With it we can uncompress DataStream partly.

DeflateStream() [2/3]

Ogre::DeflateStream::DeflateStream	(	const String &	name,
		const DataStreamPtr &	compressedStream,
		const String &	tmpFileName = "",
		size_t	avail_in = 0
	)

Constructor for creating named stream wrapping another stream.

Parameters

name	The name to give this stream
compressedStream	The stream that this stream will use when reading / writing compressed data. The access mode from this stream will be matched.
tmpFileName	Path/Filename to be used for temporary storage of incoming data
avail_in	Available data length to be uncompressed. With it we can uncompress DataStream partly.

DeflateStream() [3/3]

Ogre::DeflateStream::DeflateStream	(	const String &	name,
		const DataStreamPtr &	compressedStream,
		StreamType	streamType,
		const String &	tmpFileName = "",
		size_t	avail_in = 0
	)

Constructor for creating named stream wrapping another stream.

Parameters

name	The name to give this stream
compressedStream	The stream that this stream will use when reading / writing compressed data. The access mode from this stream will be matched.
streamType	The type of compressed stream
tmpFileName	Path/Filename to be used for temporary storage of incoming data
avail_in	Available data length to be uncompressed. With it we can uncompress DataStream partly.

~DeflateStream()

Ogre::DeflateStream::~DeflateStream

(

)

Member Function Documentation

isCompressedStreamValid()

bool Ogre::DeflateStream::isCompressedStreamValid ( ) const

inline

Returns whether the compressed stream is valid deflated data.

If you pass this class a READ stream which is not compressed with the deflate algorithm, this method returns false and all read commands will actually be executed as passthroughs as a fallback.

read()

size_t Ogre::DeflateStream::read ( void *  buf, size_t  count  )

overridevirtual

Read the requisite number of bytes from the stream, stopping at the end of the file.

Parameters

buf	Reference to a buffer pointer
count	Number of bytes to read

Returns

The number of bytes read

Implements Ogre::DataStream.

write()

size_t Ogre::DeflateStream::write ( const void *  buf, size_t  count  )

overridevirtual

Write the requisite number of bytes from the stream (only applicable to streams that are not read-only)

Parameters

buf	Pointer to a buffer containing the bytes to write
count	Number of bytes to write

Returns

The number of bytes written

Reimplemented from Ogre::DataStream.

skip()

void Ogre::DeflateStream::skip ( long  count )

overridevirtual

Skip a defined number of bytes.

This can also be a negative value, in which case the file pointer rewinds a defined number of bytes.

Implements Ogre::DataStream.

seek()

void Ogre::DeflateStream::seek ( size_t  pos )

overridevirtual

Repositions the read point to a specified byte.

Implements Ogre::DataStream.

tell()

size_t Ogre::DeflateStream::tell ( void  ) const

overridevirtual

Returns the current byte offset from beginning.

Implements Ogre::DataStream.

eof()

bool Ogre::DeflateStream::eof ( void  ) const

overridevirtual

Returns true if the stream has reached the end.

Implements Ogre::DataStream.

close()

void Ogre::DeflateStream::close ( void  )

overridevirtual

Close the stream; this makes further operations invalid.

Implements Ogre::DataStream.

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The documentation for this class was generated from the following file:

• OgreDeflate.h