FileReader Class Reference

Optimal file reader. More...

#include <base/io/FileReader.h>

Inherits Object.

Public Types
typedef SequenceIterator< ReadIteratorTraits< uint8 > >	ReadIterator

Public Member Functions
	FileReader (File &file, long long position, unsigned int windowSize=DEFAULT_WINDOW_SIZE)
const uint8 *	getBytes () const noexcept
MemorySize	getSize () const noexcept
long long	getPosition () const noexcept
ReadIterator	peek (unsigned int size)
void	read (uint8 *buffer, unsigned int size)
void	seek (long long position)
void	skip (unsigned int size)

Static Public Attributes
static constexpr unsigned int	DEFAULT_WINDOW_SIZE = 0x10000

Protected Member Functions
FileRegion	fixRegion (const FileRegion &region) noexcept
void	requestRegion (const FileRegion &region)

Detailed Description

Optimal file reader.

File reader utilizing the file mapping support.

Version

1.0

Member Typedef Documentation

ReadIterator

typedef SequenceIterator<ReadIteratorTraits<uint8> > FileReader::ReadIterator

Iterator used to traverse the elements within the current file mapping window.

Constructor & Destructor Documentation

FileReader()

FileReader::FileReader	(	File &	file,
		long long	position,
		unsigned int	windowSize = DEFAULT_WINDOW_SIZE
	)

Initializes the object.

Parameters

file	The file.
position	The initial position.
windowSize	The preferred size of the mapping window. The actual window size used may be less or greater.

Member Function Documentation

getBytes()

const uint8* FileReader::getBytes ( ) const

inlinenoexcept

Returns the bytes of the entire window.

getPosition()

long long FileReader::getPosition ( ) const

inlinenoexcept

Returns the current position indexed from the beginning of the file.

getSize()

MemorySize FileReader::getSize ( ) const

inlinenoexcept

Returns the available bytes.

peek()

ReadIterator FileReader::peek ( unsigned int  size )

inline

Ensures that the specified number of bytes are mapped without changing the current position. Raises IOException if requested number of bytes cannot be mapped.

Parameters

size	The number of bytes to peek at.

Returns

A ReadIterator to the first element.

read()

void FileReader::read	(	uint8 *	buffer,
		unsigned int	size
	)

Fills the specified buffer with the requested number of bytes and increments the position, respectively.

Parameters

buffer	The buffer.
size	The number of bytes the copy to the buffer.

requestRegion()

void FileReader::requestRegion ( const FileRegion &  region )

protected

Requests mapping of the specified region.

Parameters

region

The region to be mapped.

seek()

void FileReader::seek ( long long  position )

inline

Sets the current position indexed from the beginning of the file. Used this method if you want to skip a large number of bytes. Raises IOException if the postion exceeds the end of the file.

Parameters

position

The desired postion.

skip()

void FileReader::skip ( unsigned int  size )

inline

Skips the specified number of bytes. Normally used to skip a small number of bytes.

Parameters

size	The number of bytes to skip.

Member Data Documentation

DEFAULT_WINDOW_SIZE

constexpr unsigned int FileReader::DEFAULT_WINDOW_SIZE = 0x10000

staticconstexpr

The default preferred window size.