fileperblock_file< base_file_type > Class Template Reference

Implementation of file based on other files, dynamically allocate one file per block. Allows for dynamic disk space consumption. More...

#include <fileperblock_file.h>

Inheritance diagram for fileperblock_file< base_file_type >:

Collaboration diagram for fileperblock_file< base_file_type >:

Public Member Functions
	fileperblock_file (const std::string &filename_prefix, int mode, int queue_id=DEFAULT_QUEUE, int allocator_id=NO_ALLOCATOR)
	constructs file object More...
virtual void	serve (const request *req) throw (io_error)
virtual void	set_size (offset_type new_size)
	Changes the size of the file. More...
virtual offset_type	size ()
	Returns size of the file. More...
virtual void	lock ()
	Locks file for reading and writing (acquires a lock in the file system) More...
virtual void	discard (offset_type offset, offset_type length)
	Frees the specified region. Actually deletes the corresponding file if the whole thing is deleted. More...
virtual void	export_files (offset_type offset, offset_type length, std::string filename)
	Rename the file corresponding to the offset such that it is out of reach for deleting. More...
const char *	io_type () const
	Identifies the type of I/O implementation. More...
Public Member Functions inherited from 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)
	Schedules an asynchronous read request to the file. More...
request_ptr	awrite (void *buffer, offset_type pos, size_type bytes, const completion_handler &on_cmpl)
	Schedules an asynchronous write request to the file. More...
virtual int	get_queue_id () const
	Returns the identifier of the file's queue. More...
virtual int	get_allocator_id () const
	Returns the file's allocator. More...
Public Member Functions inherited from file
void	add_request_ref ()
void	delete_request_ref ()
int	get_request_nref ()
virtual int	get_physical_device_id () const
virtual void	remove ()

Protected Member Functions
std::string	filename_for_block (unsigned_type offset)
	Constructs a file name for a given block. More...
Protected Member Functions inherited from file
	file ()
	Initializes file object. More...

Additional Inherited Members
Public Types inherited from file
enum	open_mode {   RDONLY = 1, WRONLY = 2, RDWR = 4, CREAT = 8,   DIRECT = 16, TRUNC = 32, SYNC = 64, NO_LOCK = 128 }
	Definition of acceptable file open modes. More...
typedef request::offset_type	offset_type
typedef request::size_type	size_type
Static Public Attributes inherited from file
static const int	DEFAULT_QUEUE = -1
static const int	NO_QUEUE = -2
static const int	NO_ALLOCATOR = -1

Detailed Description

template<class base_file_type>
class fileperblock_file< base_file_type >

Implementation of file based on other files, dynamically allocate one file per block. Allows for dynamic disk space consumption.

Constructor & Destructor Documentation

template<class base_file_type >

__STXXL_BEGIN_NAMESPACE fileperblock_file< base_file_type >::fileperblock_file	(	const std::string &	filename_prefix,
		int	mode,
		int	queue_id = DEFAULT_QUEUE,
		int	allocator_id = NO_ALLOCATOR
	)

constructs file object

Parameters

filename_prefix	filename prefix, numbering will be appended to it
mode	open mode, see file::open_modes
disk	disk(file) identifier

Member Function Documentation

template<class base_file_type >

void fileperblock_file< base_file_type >::discard ( offset_type  offset, offset_type  length  )

virtual

Frees the specified region. Actually deletes the corresponding file if the whole thing is deleted.

Reimplemented from file.

template<class base_file_type >

void fileperblock_file< base_file_type >::export_files ( offset_type  offset, offset_type  length, std::string  filename  )

virtual

Rename the file corresponding to the offset such that it is out of reach for deleting.

Reimplemented from file.

template<class base_file_type >

std::string fileperblock_file< base_file_type >::filename_for_block ( unsigned_type  offset )

protected

Constructs a file name for a given block.

template<class base_file_type >

const char * fileperblock_file< base_file_type >::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 file.

template<class base_file_type >

void fileperblock_file< base_file_type >::lock ( )

virtual

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

Implements file.

References request_interface::wait().

template<class base_file_type>

virtual void fileperblock_file< base_file_type >::set_size ( offset_type  new_size )

inlinevirtual

Changes the size of the file.

Parameters

new_size

value of the new file size

Implements file.

template<class base_file_type>

virtual offset_type fileperblock_file< base_file_type >::size ( )

inlinevirtual

Returns size of the file.

Returns

file size in length

Implements file.

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

• fileperblock_file.h
• fileperblock_file.cpp