Block compressor that uses the QUICKLZ algorithm. More...

#include <BlockCompressionCodecQuicklz.h>

Inheritance diagram for Hypertable::BlockCompressionCodecQuicklz:

Collaboration diagram for Hypertable::BlockCompressionCodecQuicklz:

Public Member Functions
	BlockCompressionCodecQuicklz (const Args &args)
	Constructor. More...

virtual	~BlockCompressionCodecQuicklz ()
	Destructor. More...

virtual void	deflate (const DynamicBuffer &input, DynamicBuffer &output, BlockHeader &header, size_t reserve=0)
	Compresses a buffer using the QUICKLZ algorithm. More...

virtual void	inflate (const DynamicBuffer &input, DynamicBuffer &output, BlockHeader &header)
	Decompresses a buffer compressed with the QUICKLZ algorithm. More...

virtual int	get_type ()
	Returns enum value representing compression type QUICKLZ. More...

Public Member Functions inherited from Hypertable::BlockCompressionCodec
virtual	~BlockCompressionCodec ()
	Destructor. More...

virtual void	set_args (const Args &args)
	Sets arguments to control compression behavior. More...

Private Attributes
qlz_state_compress	m_compress
	Compression state. More...

qlz_state_decompress	m_decompress
	Decompression state. More...

Additional Inherited Members
Public Types inherited from Hypertable::BlockCompressionCodec
enum	Type { UNKNOWN =-1, NONE =0, BMZ =1, ZLIB =2, LZO =3, QUICKLZ =4, SNAPPY =5, COMPRESSION_TYPE_LIMIT =6 }
	Enumeration for compression type. More...

typedef std::vector< String >	Args
	Compression codec argument vector. More...

Static Public Member Functions inherited from Hypertable::BlockCompressionCodec
static const char *	get_compressor_name (uint16_t algo)
	Returns string mnemonic for compression type. More...

Detailed Description

Block compressor that uses the QUICKLZ algorithm.

This class provides a way to compress and decompress blocks of data using the quicklz algorithm, a general purpose compression algorithm that provides good compression speed. The quicklz compression algorithm is appropriate for compressing blocks for things like the commit log where compression speed is more important than decompression speed.

Definition at line 45 of file BlockCompressionCodecQuicklz.h.

Constructor & Destructor Documentation

Hypertable::BlockCompressionCodecQuicklz::BlockCompressionCodecQuicklz ( const Args & args )

inline

Constructor.

This constructor passes args to the default implementation of set_args() since it does not support any arguments.

Parameters

args	Arguments to control compression behavior

Exceptions

Exception Code set to Error::BLOCK_COMPRESSOR_INVALID_ARG

Definition at line 54 of file BlockCompressionCodecQuicklz.h.

virtual Hypertable::BlockCompressionCodecQuicklz::~BlockCompressionCodecQuicklz ( )

inlinevirtual

Destructor.

Definition at line 57 of file BlockCompressionCodecQuicklz.h.

Member Function Documentation

void BlockCompressionCodecQuicklz::deflate	(	const DynamicBuffer &	input,
		DynamicBuffer &	output,
		BlockHeader &	header,
		size_t	reserve = `0`
	)

virtual

Compresses a buffer using the QUICKLZ algorithm.

This method reserves enough space in output to hold the serialized header followed by the compressed input followed by reserve bytes. If the resulting compressed buffer is larger than the input buffer, then the input buffer is copied directly to the output buffer and the compression type is set to BlockCompressionCodec::NONE. Before serailizing header, the data_length, data_zlength, data_checksum, and compression_type fields are set appropriately. The output buffer is formatted as follows:

header

compressed data

reserve

Parameters