DataWriter Class Reference

Writes data to storage. More...

#include <DataWriter.h>

Public Member Functions
	DataWriter (Index &index, const stdString &channel_name, const CtrlInfo &ctrl_info, DbrType dbr_type, DbrCount dbr_count, double period, size_t num_samples)
	Create a writer for the given index. More...
	~DataWriter ()
	Destructor. More...
epicsTime	getLastStamp ()
	Returns the last time stamp in the archive. More...
bool	add (const RawValue::Data *data)
	Add a value. More...
void	write (DbrType type, DbrCount count, size_t size, const RawValue::Data *value, MemoryBuffer< dbr_time_string > &cvt_buffer, class DataFile *datafile, FileOffset offset)
	Write a value to binary file. More...
dbr_time_string *	write1 (size_t size, MemoryBuffer< dbr_time_string > &cvt_buffer, class DataFile *datafile)
	write 1
void	write2 (dbr_time_string *buffer, size_t size, const RawValue::Data *value)
	write 2
void	write3 (dbr_time_string *buffer)
	write 3
void	write4 (DbrType type, DbrCount count, dbr_time_string *buffer, size_t size, const RawValue::Data *value, class DataFile *datafile, FileOffset offset)
	write 4
void	write5a (class DataFile *datafile, FileOffset offset)
	write 5a
void	write5b (class DataFile *datafile, FileOffset offset)
	write 5b
void	write6 (dbr_time_string *buffer, size_t size, class DataFile *datafile, FileOffset offset)
	write 6

Static Public Attributes
static FileOffset	file_size_limit
	Data file size limit.
static stdString	data_file_name_base
	Base name of data files. More...

Detailed Description

Writes data to storage.

The data writer interfaces between a series of RawValue values and the Index/DataFile.

Constructor & Destructor Documentation

DataWriter::DataWriter	(	Index &	index,
		const stdString &	channel_name,
		const CtrlInfo &	ctrl_info,
		DbrType	dbr_type,
		DbrCount	dbr_count,
		double	period,
		size_t	num_samples
	)

Create a writer for the given index.

Parameters

index,:	index file
channel_name,:	name of the channel
ctrl_info,:	meta information for the channel
dbr_type,:	the dbr_time_xxx type
dbr_count,:	array size
period,:	estimated periodicity of the channel
num_samples,:	estimated number of samples (helps w/ buffer allocation)

Exceptions

GenericException

on error.

DataWriter::~DataWriter

(

)

Destructor.

Note: Since one might use another DataWriter to add to the same set of data files, the DataWriter does not clear the DataFile cache. Call DataFile::close_all() when done!

Member Function Documentation

bool DataWriter::add

(

const RawValue::Data *

data

)

Add a value.

Returns

Returns true if the sample was added, false if the sample goes back-in-time and is thus ignored.

Exceptions

GenericException

on error.

epicsTime DataWriter::getLastStamp

(

)

Returns the last time stamp in the archive.

This allows you to avoid the back-in-time error by checking before adding. The result is a null time stamp in case there's nothing in the archive, yet.

void DataWriter::write	(	DbrType	type,
		DbrCount	count,
		size_t	size,
		const RawValue::Data *	value,
		MemoryBuffer< dbr_time_string > &	cvt_buffer,
		class DataFile *	datafile,
		FileOffset	offset
	)

Write a value to binary file.

Requires a buffer for the memory-to-disk format conversions.

Exceptions

GenericException

on error.

Member Data Documentation

stdString DataWriter::data_file_name_base

static

Base name of data files.

If not set, the date and time is used.

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

• /home/malitsky/projects/epics-archiver/sourceforge/trunk/ea4-cpp/include/classic/storage/DataWriter.h