LCWriter class. More...

#include <LCWriter.h>

Public Member Functions
	LCWriter ()=default
	Default constructor. More...

	LCWriter (const LCWriter &)=delete
	no copy constructor More...

LCWriter &	operator= (const LCWriter &)=delete
	no assignment operator More...

	~LCWriter ()=default
	Destructor. More...

void	open (const std::string &filename)
	Opens a file for writing. More...

void	open (const std::string &filename, int writeMode)
	Opens a file for writing. More...

void	setCompressionLevel (int level)
	Set the compression level - needs to be called before open() otherwise call will have no effect. More...

void	writeRunHeader (EVENT::LCRunHeader *hdr)
	Writes the given run header to file. More...

void	writeEvent (EVENT::LCEvent *evt)
	Writes the given event to file. More...

void	writeEvent (EVENT::LCEvent *evt, const std::set< std::string > &colsOnly)
	Writes the given event to file, but write only the spcified collections. More...

void	close ()
	Closes the output file/stream. More...

Static Private Member Functions
static std::string	getSIOFileName (const std::string &filename)

Private Attributes
std::ofstream	_stream {}
	The output file stream. More...

std::atomic< unsigned int >	_maxBufferSize {212041024}
	The compression level. More...

std::atomic< int >	_compressionLevel {-1}
	The compression level. More...

std::shared_ptr < SIO::LCIORandomAccessMgr >	_raMgr {nullptr}
	The random access manager for event/run random access in the file. More...

std::mutex	_mutex {}
	Synchronization mutex. More...

Detailed Description

LCWriter class.

    Implement a writer for events and run headers using SIO.
    Thread safety specifications:
    - Writing two events from different threads is safe
    - Writing an event and a run header from different threads is safe
    - Opening/closing a file and writing might throw an exception depending on the scheduling
    A mutex ensures that no data race will occur but won't protect
    against race conditions

Author: R. Ete, DESY

Definition at line 42 of file LCWriter.h.

Constructor & Destructor Documentation

MT::LCWriter::LCWriter ( )

default

Default constructor.

MT::LCWriter::LCWriter ( const LCWriter & )

delete

no copy constructor

MT::LCWriter::~LCWriter ( )

default

Destructor.

Member Function Documentation

void MT::LCWriter::close ( )

Closes the output file/stream.

Definition at line 202 of file LCWriter.cc.

References _mutex, _raMgr, _stream, and std::ofstream::close().

std::string MT::LCWriter::getSIOFileName ( const std::string & filename )

staticprivate

Definition at line 212 of file LCWriter.cc.

References SIO::LCSIO::FileExtension, std::string::length(), and std::string::rfind().

Referenced by open().

void MT::LCWriter::open ( const std::string & filename )

Opens a file for writing.

If file with given name exists, an exception is thrown. Use append or new mode instead.

Definition at line 21 of file LCWriter.cc.

References getSIOFileName().

void MT::LCWriter::open	(	const std::string &	filename,
		int	writeMode
	)

Opens a file for writing.

Possible write modes are: LCIO::WRITE_NEW (existing files are replaced) and LCIO::WRITE_APPEND.

Definition at line 37 of file LCWriter.cc.

References _mutex, _raMgr, _stream, getSIOFileName(), std::ofstream::good(), std::ofstream::is_open(), std::ofstream::open(), SIO::LCSIO::RandomAccessSize, std::ofstream::seekp(), std::stringstream::str(), and std::ofstream::tellp().

LCWriter& MT::LCWriter::operator= ( const LCWriter & )

delete

no assignment operator

void MT::LCWriter::setCompressionLevel ( int level )

Set the compression level - needs to be called before open() otherwise call will have no effect.

If not called the Writer will use default compression.
Valid compression levels are:

level < 0 : default compression
level == 0 : no compression
level > 0 : compression level (typically 1 (fastest) - 9 (best compression)) No data race expected (atomic variable in use) but a race condition can occur if the compression level is set while write a record

Parameters

level compression level

Definition at line 84 of file LCWriter.cc.

References _compressionLevel.

void MT::LCWriter::writeEvent ( EVENT::LCEvent * evt )

Writes the given event to file.

Definition at line 140 of file LCWriter.cc.