ROOT::Experimental::Detail::RNTupleCompressor Class Reference

Helper class to compress data blocks in the ROOT compression frame format.

Definition at line 40 of file RNTupleZip.hxx.

Public Types
using	Writer_t = std::function< void(const void *buffer, size_t nbytes, size_t offset)>
	Data might be overwritten, if a zipped block in the middle of a large input data stream turns out to be uncompressible.

Public Member Functions
	RNTupleCompressor ()
	RNTupleCompressor (const RNTupleCompressor &other)=delete
	RNTupleCompressor (RNTupleCompressor &&other)=default
const void *	GetZipBuffer ()
size_t	operator() (const void *from, size_t nbytes, int compression)
	Returns the size of the compressed data block.
size_t	operator() (const void *from, size_t nbytes, int compression, Writer_t fnWriter)
	Returns the size of the compressed data.
RNTupleCompressor &	operator= (const RNTupleCompressor &other)=delete
RNTupleCompressor &	operator= (RNTupleCompressor &&other)=default

Static Public Attributes
static constexpr size_t	kMaxSingleBlock = kMAXZIPBUF

Private Types
using	Buffer_t = std::array< unsigned char, kMAXZIPBUF >

Private Attributes
std::unique_ptr< Buffer_t >	fZipBuffer

#include <ROOT/RNTupleZip.hxx>

Member Typedef Documentation

Buffer_t

using ROOT::Experimental::Detail::RNTupleCompressor::Buffer_t = std::array<unsigned char, kMAXZIPBUF>

private

Definition at line 42 of file RNTupleZip.hxx.

Writer_t

using ROOT::Experimental::Detail::RNTupleCompressor::Writer_t = std::function<void(const void *buffer, size_t nbytes, size_t offset)>

Data might be overwritten, if a zipped block in the middle of a large input data stream turns out to be uncompressible.

Definition at line 48 of file RNTupleZip.hxx.

Constructor & Destructor Documentation

RNTupleCompressor() [1/3]

ROOT::Experimental::Detail::RNTupleCompressor::RNTupleCompressor ( )

inline

Definition at line 51 of file RNTupleZip.hxx.

RNTupleCompressor() [2/3]

ROOT::Experimental::Detail::RNTupleCompressor::RNTupleCompressor ( const RNTupleCompressor &  other )

delete

RNTupleCompressor() [3/3]

ROOT::Experimental::Detail::RNTupleCompressor::RNTupleCompressor ( RNTupleCompressor &&  other )

default

Member Function Documentation

GetZipBuffer()

const void * ROOT::Experimental::Detail::RNTupleCompressor::GetZipBuffer ( )

inline

Definition at line 123 of file RNTupleZip.hxx.

operator()() [1/2]

size_t ROOT::Experimental::Detail::RNTupleCompressor::operator() ( const void *  from, size_t  nbytes, int  compression  )

inline

Returns the size of the compressed data block.

The data is written into the zip buffer. This works only for small input buffer up to 16MB

Definition at line 98 of file RNTupleZip.hxx.

operator()() [2/2]

size_t ROOT::Experimental::Detail::RNTupleCompressor::operator() ( const void *  from, size_t  nbytes, int  compression, Writer_t  fnWriter  )

inline

Returns the size of the compressed data.

Data is compressed in 16MB blocks and written piecewise using the provided writer

Definition at line 59 of file RNTupleZip.hxx.

operator=() [1/2]

RNTupleCompressor & ROOT::Experimental::Detail::RNTupleCompressor::operator= ( const RNTupleCompressor &  other )

delete

operator=() [2/2]

RNTupleCompressor & ROOT::Experimental::Detail::RNTupleCompressor::operator= ( RNTupleCompressor &&  other )

default

Member Data Documentation

fZipBuffer

std::unique_ptr<Buffer_t> ROOT::Experimental::Detail::RNTupleCompressor::fZipBuffer

private

Definition at line 43 of file RNTupleZip.hxx.

kMaxSingleBlock

constexpr size_t ROOT::Experimental::Detail::RNTupleCompressor::kMaxSingleBlock = kMAXZIPBUF

staticconstexpr

Definition at line 49 of file RNTupleZip.hxx.

Libraries for ROOT::Experimental::Detail::RNTupleCompressor:

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

• tree/ntuple/v7/inc/ROOT/RNTupleZip.hxx