libcdoc::DataSource Struct Reference

The DataSource class. More...

#include <Io.h>

Inherited by libcdoc::ChainedSource, libcdoc::IStreamSource, libcdoc::MultiDataSource, and libcdoc::VectorSource.

Public Member Functions
	DataSource ()=default
virtual	~DataSource ()=default
virtual result_t	seek (size_t pos)
	set stream input pointer
virtual result_t	read (uint8_t *dst, size_t size)
	read bytes from input object
virtual bool	isError ()
	check whether DataConsumer is in error state
virtual bool	isEof ()
	check whether DataConsumer is reached to the end of data
virtual std::string	getLastErrorStr (result_t code) const
	get textual description of the last error
result_t	skip (size_t size)
	skip specified number of bytes
result_t	readAll (DataConsumer &dst)
	read all data and writes to output object
	DataSource (const DataSource &)=delete
DataSource &	operator= (const DataSource &)=delete

Detailed Description

The DataSource class.

An abstact base class for input objects

Constructor & Destructor Documentation

DataSource() [1/2]

libcdoc::DataSource::DataSource ( )

default

~DataSource()

virtual libcdoc::DataSource::~DataSource ( )

virtualdefault

DataSource() [2/2]

libcdoc::DataSource::DataSource ( const DataSource &  )

delete

Member Function Documentation

getLastErrorStr()

virtual std::string libcdoc::DataSource::getLastErrorStr ( result_t  code ) const

virtual

get textual description of the last error

Implementation can decide whether to store the actual error string or return the generic text based on error code. It is undefined what will be returned if the last error code is not the one used as the argument.

Parameters

code	the last returned error code

Returns

error text

isEof()

virtual bool libcdoc::DataSource::isEof ( )

inlinevirtual

check whether DataConsumer is reached to the end of data

Returns

true if end of stream

Reimplemented in libcdoc::ChainedSource, libcdoc::IStreamSource, libcdoc::VectorSource, and libcdoc::FileListSource.

isError()

virtual bool libcdoc::DataSource::isError ( )

inlinevirtual

check whether DataConsumer is in error state

Returns

true if error state

Reimplemented in libcdoc::ChainedSource, libcdoc::IStreamSource, libcdoc::VectorSource, and libcdoc::FileListSource.

operator=()

DataSource & libcdoc::DataSource::operator= ( const DataSource &  )

delete

read()

virtual result_t libcdoc::DataSource::read ( uint8_t *  dst, size_t  size  )

inlinevirtual

read bytes from input object

The following invariant holds:

• if there is neither error nor eof then result == size
• if there is no errors but end of stream is reached then 0 <= result <= size
• if there is error then result < 0

  Parameters

  dst	the destination block
  size	the number of bytes to read

  Returns

  the number of bytes read or error code

Reimplemented in libcdoc::ChainedSource, libcdoc::IStreamSource, libcdoc::VectorSource, and libcdoc::FileListSource.

References libcdoc::NOT_IMPLEMENTED.

readAll()

result_t libcdoc::DataSource::readAll ( DataConsumer &  dst )

inline

read all data and writes to output object

Copies all bytes (until EOF or error) to the output object. If error occurs while writing data, the destination objects' error code is returned.

Parameters

dst	the destination DataConsumer

Returns

error code or OK

References libcdoc::DataConsumer::writeAll().

seek()

virtual result_t libcdoc::DataSource::seek ( size_t  pos )

inlinevirtual

set stream input pointer

Positions the read pointer at the specific distance from the stream start. If the stream does not support seeking NOT_IMPLEMENTED is returned.

Parameters

pos	the position from the beggining of data

Returns

error code or OK

Reimplemented in libcdoc::IStreamSource, and libcdoc::VectorSource.

References libcdoc::NOT_IMPLEMENTED.

skip()

result_t libcdoc::DataSource::skip

(

size_t

size

)

skip specified number of bytes

The following invariant holds:

• if there is neither error nor eof then result == size
• if there is no errors but end of stream is reached then 0 <= result <= size
• if there is error then result < 0

  Parameters

  size	the number of bytes to skip

  Returns

  the number of bytes skipped

---

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

• Io.h