tkrzw::ZLibCompressor Class Reference

Compressor implemeted with ZLib. More...

#include <tkrzw_compress.h>

Public Types
enum	MetadataMode : int32_t { METADATA_NONE = 0 , METADATA_ADLER32 = 1 , METADATA_CRC32 = 2 }
	Enumeration for metadata modes. More...

Public Member Functions
	ZLibCompressor (int32_t level=6, MetadataMode metadata_mode=METADATA_NONE)
	Constructor. More...
virtual	~ZLibCompressor ()
	Destructor. More...
bool	IsSupported () const override
	Checks whether the implementation is actually supported. More...
char *	Compress (const void *buf, size_t size, size_t *sp) const override
	Compresses a serial data. More...
char *	Decompress (const void *buf, size_t size, size_t *sp) const override
	Decompresses a serial data. More...
std::unique_ptr< Compressor >	MakeCompressor () const override
	Makes a new Compressor object of the same concrete class. More...
Public Member Functions inherited from tkrzw::Compressor
virtual	~Compressor ()=default
	Destructor. More...
const std::type_info &	GetType () const
	Gets the type information of the actual class. More...

Detailed Description

Compressor implemeted with ZLib.

Member Enumeration Documentation

MetadataMode

enum tkrzw::ZLibCompressor::MetadataMode : int32_t

Enumeration for metadata modes.

Enumerator
METADATA_NONE	Without any checksum.
METADATA_ADLER32	With Adler-32 checksum, compatible with deflate.
METADATA_CRC32	With CRC-32 checksum, compatible with gzip.

Constructor & Destructor Documentation

ZLibCompressor()

tkrzw::ZLibCompressor::ZLibCompressor ( int32_t  level = 6, MetadataMode  metadata_mode = METADATA_NONE  )

explicit

Constructor.

Parameters

level	The compression level between 0 and 9. Higher means slower but better compression. 0 means no compression.
metadata_mode	The mode for the metadata added to the result.

~ZLibCompressor()

virtual tkrzw::ZLibCompressor::~ZLibCompressor ( )

virtual

Destructor.

Member Function Documentation

IsSupported()

bool tkrzw::ZLibCompressor::IsSupported ( ) const

overridevirtual

Checks whether the implementation is actually supported.

Returns

True if the implementation is actually supported.

Implements tkrzw::Compressor.

Compress()

char* tkrzw::ZLibCompressor::Compress ( const void *  buf, size_t  size, size_t *  sp  ) const

overridevirtual

Compresses a serial data.

Parameters

buf	the input buffer.
size	the size of the input buffer.
sp	the pointer to the variable into which the size of the region of the return value is assigned.

Returns

The pointer to the result data, or nullptr on failure.

Because the region of the return value is allocated with the xmalloc function, it should be released with the xfree function.

Implements tkrzw::Compressor.

Decompress()

char* tkrzw::ZLibCompressor::Decompress ( const void *  buf, size_t  size, size_t *  sp  ) const

overridevirtual

Decompresses a serial data.

Parameters

buf	the input buffer.
size	the size of the input buffer.
sp	the pointer to the variable into which the size of the region of the return value is assigned.

Returns

The pointer to the result data, or nullptr on failure.

Because the region of the return value is allocated with the xmalloc function, it should be released with the xfree function.

Implements tkrzw::Compressor.

MakeCompressor()

std::unique_ptr<Compressor> tkrzw::ZLibCompressor::MakeCompressor ( ) const

overridevirtual

Makes a new Compressor object of the same concrete class.

Returns

The new Compressor object.

Implements tkrzw::Compressor.