Stxxl: 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 >:

Inheritance graph

Collaboration diagram for fileperblock_file< base_file_type >:

Collaboration graph

List of all members.

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
virtual void	serve (const request *req) throw (io_error)
virtual void	set_size (offset_type new_size)
	Changes the size of the file.
virtual offset_type	size ()
	Returns size of the file.
virtual void	lock ()
	Locks file for reading and writing (acquires a lock in the file system).
virtual void	discard (offset_type offset, offset_type length)
	Frees the specified region. Actually deletes the corresponding file if the whole thing is deleted.
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.
const char *	io_type () const
	Identifies the type of I/O implementation.
Protected Member Functions
std::string	filename_for_block (unsigned_type offset)
	Constructs a file name for a given block.

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.

References fileperblock_file< base_file_type >::filename_for_block().

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.

References fileperblock_file< base_file_type >::filename_for_block().

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.

Referenced by fileperblock_file< base_file_type >::discard(), and fileperblock_file< base_file_type >::export_files().

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.

template<class base_file_type>

virtual void fileperblock_file< base_file_type >::set_size ( offset_type new_size ) [inline, virtual]

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 ( ) [inline, virtual]

Returns size of the file.

Returns:: file size in length

Implements file.

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

fileperblock_file.h
fileperblock_file.cpp