Detailed Description

Implementation of file based on buffered writes and block remapping via a translation layer.

Definition at line 36 of file wbtl_file.h.

Inheritance diagram for stxxl::wbtl_file:

Collaboration diagram for stxxl::wbtl_file:

Classes
struct	FirstFit

Public Member Functions
	wbtl_file (file *backend_file, size_type write_buffer_size, int write_buffers=2, int queue_id=DEFAULT_QUEUE, int allocator_id=NO_ALLOCATOR)
	Constructs file object. param backend_file file object used as storage backend, will be deleted in ~wbtl_file() More...

	~wbtl_file ()

void	discard (offset_type offset, offset_type size)

const char *	io_type () const
	Identifies the type of I/O implementation. More...

void	lock ()
	Locks file for reading and writing (acquires a lock in the file system). More...

void	serve (void *buffer, offset_type offset, size_type bytes, request::request_type type)

void	set_size (offset_type newsize)

offset_type	size ()
	Returns size of the file. More...

Public Member Functions inherited from stxxl::disk_queued_file
	disk_queued_file (int queue_id, int allocator_id)

request_ptr	aread (void *buffer, offset_type pos, size_type bytes, const completion_handler &on_cmpl=completion_handler())

request_ptr	awrite (void *buffer, offset_type pos, size_type bytes, const completion_handler &on_cmpl=completion_handler())

virtual int	get_allocator_id () const
	Returns the file's disk allocator number. More...

virtual int	get_queue_id () const
	Returns the identifier of the file's queue number. More...

Public Member Functions inherited from stxxl::file
	file (unsigned int device_id=DEFAULT_DEVICE_ID)
	Construct a new file, usually called by a subclass. More...

virtual	~file () noexcept(false)

void	add_request_ref ()
	increment referenced requests More...

virtual request_ptr	aread (void *buffer, offset_type pos, size_type bytes, const completion_handler &on_cmpl=completion_handler())=0
	Schedules an asynchronous read request to the file. More...

virtual request_ptr	awrite (void *buffer, offset_type pos, size_type bytes, const completion_handler &on_cmpl=completion_handler())=0
	Schedules an asynchronous write request to the file. More...

virtual void	close_remove ()
	close and remove file More...

void	delete_request_ref ()
	decrement referenced requests More...

virtual void	discard (offset_type offset, offset_type size)
	Discard a region of the file (mark it unused). Some specialized file types may need to know freed regions. More...

virtual void	export_files (offset_type offset, offset_type length, std::string prefix)

unsigned int	get_device_id () const
	Returns the file's physical device id. More...

unsigned_type	get_request_nref ()
	return number of referenced requests More...

virtual void	serve (void *buffer, offset_type offset, size_type bytes, request::request_type type)=0

virtual void	set_size (offset_type newsize)=0
	Changes the size of the file. More...

Protected Member Functions
void	check_corruption (offset_type region_pos, offset_type region_size, sortseq::iterator pred, sortseq::iterator succ)

offset_type	get_next_write_block ()

void	sread (void *buffer, offset_type offset, size_type bytes)

void	swrite (void *buffer, offset_type offset, size_type bytes)

Private Types
typedef std::pair< offset_type, offset_type >	place

typedef std::map< offset_type, place >	place_map

typedef std::map< offset_type, offset_type >	sortseq

Private Member Functions
void	_add_free_region (offset_type offset, offset_type size)

Private Attributes
sortseq	address_mapping

request_ptr	backend_request

offset_type	buffer_address [2]

mutex	buffer_mutex

int	curbuf

size_type	curpos

offset_type	free_bytes

sortseq	free_space

mutex	mapping_mutex

place_map	reverse_mapping

file *	storage

offset_type	sz

size_type	write_block_size

char *	write_buffer [2]

Additional Inherited Members
Public Types inherited from stxxl::file
typedef request::offset_type	offset_type
	the offset of a request, also the size of the file More...

enum	open_mode { RDONLY = 1, WRONLY = 2, RDWR = 4, CREAT = 8, DIRECT = 16, TRUNC = 32, SYNC = 64, NO_LOCK = 128, REQUIRE_DIRECT = 256 }
	Definition of acceptable file open modes. More...

typedef request::size_type	size_type
	the size of a request More...

Static Public Member Functions inherited from stxxl::file
static int	unlink (const char *path)
	unlink path from filesystem More...

static int	truncate (const char *path, external_size_type length)
	truncate a path to given length. Use this only if you dont have a fileio-specific object, which provides truncate(). More...

Static Public Attributes inherited from stxxl::file
static const unsigned int	DEFAULT_DEVICE_ID = (unsigned int)(-1)

static const int	DEFAULT_LINUXAIO_QUEUE = -2

static const int	DEFAULT_QUEUE = -1

static const int	NO_ALLOCATOR = -1

Protected Attributes inherited from stxxl::file
unsigned int	m_device_id
	The file's physical device id (e.g. used for prefetching sequence calculation) More...

atomic_counted_object	m_request_ref
	count the number of requests referencing this file More...

Member Typedef Documentation

typedef std::pair<offset_type, offset_type> stxxl::wbtl_file::place

private

Definition at line 38 of file wbtl_file.h.

typedef std::map<offset_type, place> stxxl::wbtl_file::place_map

private

Definition at line 40 of file wbtl_file.h.

typedef std::map<offset_type, offset_type> stxxl::wbtl_file::sortseq

private

Definition at line 39 of file wbtl_file.h.

Constructor & Destructor Documentation

stxxl::wbtl_file::wbtl_file	(	file *	backend_file,
		size_type	write_buffer_size,
		int	write_buffers = `2`,
		int	queue_id = `DEFAULT_QUEUE`,
		int	allocator_id = `NO_ALLOCATOR`
	)

Constructs file object. param backend_file file object used as storage backend, will be deleted in ~wbtl_file()

stxxl::wbtl_file::~wbtl_file ( )

Member Function Documentation

void stxxl::wbtl_file::_add_free_region	(	offset_type	offset,
		offset_type	size
	)

private

void stxxl::wbtl_file::check_corruption	(	offset_type	region_pos,
		offset_type	region_size,
		sortseq::iterator	pred,
		sortseq::iterator	succ
	)

protected

void stxxl::wbtl_file::discard	(	offset_type	offset,
		offset_type	size
	)

offset_type stxxl::wbtl_file::get_next_write_block ( )

protected

const char* stxxl::wbtl_file::io_type ( ) const

virtual

Identifies the type of I/O implementation.

Returns: pointer to null terminated string of characters, containing the name of I/O implementation

Implements stxxl::file.

void stxxl::wbtl_file::lock ( )

virtual

Locks file for reading and writing (acquires a lock in the file system).

Implements stxxl::file.

Referenced by stxxl::create_file().

void stxxl::wbtl_file::serve	(	void *	buffer,
		offset_type	offset,
		size_type	bytes,
		request::request_type	type
	)

void stxxl::wbtl_file::set_size ( offset_type newsize )

offset_type stxxl::wbtl_file::size ( )

virtual

Returns size of the file.

Returns: file size in bytes

Implements stxxl::file.

void stxxl::wbtl_file::sread	(	void *	buffer,
		offset_type	offset,
		size_type	bytes
	)

protected

void stxxl::wbtl_file::swrite	(	void *	buffer,
		offset_type	offset,
		size_type	bytes
	)

protected

Member Data Documentation

sortseq stxxl::wbtl_file::address_mapping

private

Definition at line 49 of file wbtl_file.h.

request_ptr stxxl::wbtl_file::backend_request

private

Definition at line 66 of file wbtl_file.h.

offset_type stxxl::wbtl_file::buffer_address[2]

private

Definition at line 63 of file wbtl_file.h.

mutex stxxl::wbtl_file::buffer_mutex

private

Definition at line 61 of file wbtl_file.h.

int stxxl::wbtl_file::curbuf

private

Definition at line 64 of file wbtl_file.h.

size_type stxxl::wbtl_file::curpos

private

Definition at line 65 of file wbtl_file.h.

offset_type stxxl::wbtl_file::free_bytes

private

Definition at line 54 of file wbtl_file.h.

sortseq stxxl::wbtl_file::free_space

private

Definition at line 53 of file wbtl_file.h.

mutex stxxl::wbtl_file::mapping_mutex

private

Definition at line 47 of file wbtl_file.h.

place_map stxxl::wbtl_file::reverse_mapping

private

Definition at line 51 of file wbtl_file.h.

file* stxxl::wbtl_file::storage

private

Definition at line 43 of file wbtl_file.h.

offset_type stxxl::wbtl_file::sz

private

Definition at line 44 of file wbtl_file.h.

size_type stxxl::wbtl_file::write_block_size

private

Definition at line 45 of file wbtl_file.h.

char* stxxl::wbtl_file::write_buffer[2]

private

Definition at line 62 of file wbtl_file.h.

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

include/stxxl/bits/io/wbtl_file.h

Detailed Description

Classes

Public Member Functions

Protected Member Functions

Private Types

Private Member Functions

Private Attributes

Additional Inherited Members

Member Typedef Documentation

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation