stxxl::wbtl_file Class Reference

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

#include <wbtl_file.h>

Inheritance diagram for stxxl::wbtl_file:

Collaboration diagram for stxxl::wbtl_file:

List of all members.

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
	~wbtl_file ()
offset_type	size ()
	Returns size of the file.
void	set_size (offset_type newsize)
void	lock ()
	Locks file for reading and writing (acquires a lock in the file system)
void	serve (const request *req) throw (io_error)
void	discard (offset_type offset, offset_type size)
const char *	io_type () const
	Identifies the type of I/O implementation.
Protected Member Functions
void	sread (void *buffer, offset_type offset, size_type bytes)
void	swrite (void *buffer, offset_type offset, size_type bytes)
offset_type	get_next_write_block ()
void	check_corruption (offset_type region_pos, offset_type region_size, sortseq::iterator pred, sortseq::iterator succ)
Private Types
typedef std::pair< offset_type, offset_type >	place
typedef std::map< offset_type, offset_type >	sortseq
typedef std::map< offset_type, place >	place_map
Private Member Functions
void	_add_free_region (offset_type offset, offset_type size)
Private Attributes
file *	storage
offset_type	sz
size_type	write_block_size
mutex	mapping_mutex
sortseq	address_mapping
place_map	reverse_mapping
sortseq	free_space
offset_type	free_bytes
mutex	buffer_mutex
char *	write_buffer [2]
offset_type	buffer_address [2]
int	curbuf
size_type	curpos
request_ptr	backend_request

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Detailed Description

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

Definition at line 37 of file wbtl_file.h.

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Member Typedef Documentation

typedef std::pair<offset_type, offset_type> stxxl::wbtl_file::place [private]

Definition at line 39 of file wbtl_file.h.

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

Definition at line 41 of file wbtl_file.h.

typedef std::map<offset_type, offset_type> stxxl::wbtl_file::sortseq [private]

Definition at line 40 of file wbtl_file.h.

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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

Parameters:

backend_file	file object used as storage backend, will be deleted in ~wbtl_file()
disk	disk(file) identifier

stxxl::wbtl_file::~wbtl_file

(

)

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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

Reimplemented from 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

(

const request *

req

)

throw (io_error) [virtual]

Implements stxxl::file.

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]

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Member Data Documentation

sortseq stxxl::wbtl_file::address_mapping [private]

Definition at line 50 of file wbtl_file.h.

request_ptr stxxl::wbtl_file::backend_request [private]

Definition at line 67 of file wbtl_file.h.

offset_type stxxl::wbtl_file::buffer_address[2] [private]

Definition at line 64 of file wbtl_file.h.

mutex stxxl::wbtl_file::buffer_mutex [private]

Definition at line 62 of file wbtl_file.h.

int stxxl::wbtl_file::curbuf [private]

Definition at line 65 of file wbtl_file.h.

size_type stxxl::wbtl_file::curpos [private]

Definition at line 66 of file wbtl_file.h.

offset_type stxxl::wbtl_file::free_bytes [private]

Definition at line 55 of file wbtl_file.h.

sortseq stxxl::wbtl_file::free_space [private]

Definition at line 54 of file wbtl_file.h.

mutex stxxl::wbtl_file::mapping_mutex [private]

Definition at line 48 of file wbtl_file.h.

place_map stxxl::wbtl_file::reverse_mapping [private]

Definition at line 52 of file wbtl_file.h.

file* stxxl::wbtl_file::storage [private]

Definition at line 44 of file wbtl_file.h.

offset_type stxxl::wbtl_file::sz [private]

Definition at line 45 of file wbtl_file.h.

size_type stxxl::wbtl_file::write_block_size [private]

Definition at line 46 of file wbtl_file.h.

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

Definition at line 63 of file wbtl_file.h.

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

• include/stxxl/bits/io/wbtl_file.h