Detailed Description

Defines interface of file.

It is a base class for different implementations that might base on various file systems or even remote storage interfaces

Examples:: examples/applications/skew3.cpp, and examples/containers/copy_file.cpp.

Definition at line 56 of file file.h.

Inheritance diagram for stxxl::file:

Collaboration diagram for stxxl::file:

Public Types
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...

Public Member Functions
	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)

virtual int	get_allocator_id () const =0
	Returns the file's disk allocator number. More...

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

virtual int	get_queue_id () const =0
	Returns the identifier of the file's queue number. More...

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

virtual const char *	io_type () const =0
	Identifies the type of I/O implementation. More...

virtual void	lock ()=0
	Locks file for reading and writing (acquires a lock in the file system). 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...

virtual offset_type	size ()=0
	Returns size of the file. More...

Static Public Member Functions
Static Functions for Platform Abstraction
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
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
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...

Additional Inherited Members
Private Member Functions inherited from stxxl::noncopyable
	noncopyable ()

Member Typedef Documentation

typedef request::offset_type stxxl::file::offset_type

the offset of a request, also the size of the file

Definition at line 60 of file file.h.

typedef request::size_type stxxl::file::size_type

the size of a request

Definition at line 62 of file file.h.

Member Enumeration Documentation

enum stxxl::file::open_mode

Definition of acceptable file open modes.

Various open modes in a file system must be converted to this set of acceptable modes

Enumerator
RDONLY	only reading of the file is allowed
WRONLY	only writing of the file is allowed
RDWR	read and write of the file are allowed
CREAT	in case file does not exist no error occurs and file is newly created
DIRECT	I/Os proceed bypassing file system buffers, i.e. unbuffered I/O. < Tries to open with appropriate flags, if fails print warning and open normally.
TRUNC	once file is opened its length becomes zero
SYNC	open the file with O_SYNC \| O_DSYNC \| O_RSYNC flags set
NO_LOCK	do not acquire an exclusive lock by default
REQUIRE_DIRECT	implies DIRECT, fail if opening with DIRECT flag does not work.

Definition at line 68 of file file.h.

Constructor & Destructor Documentation

stxxl::file::file ( unsigned int device_id = DEFAULT_DEVICE_ID )

inline

Construct a new file, usually called by a subclass.

Definition at line 88 of file file.h.

virtual stxxl::file::~file ( )

inlinevirtualnoexcept

Definition at line 154 of file file.h.

References STXXL_ERRMSG.

Member Function Documentation

void stxxl::file::add_request_ref ( )

inline

increment referenced requests

Definition at line 186 of file file.h.

Referenced by stxxl::request::request().

virtual request_ptr stxxl::file::aread	(	void *	buffer,
		offset_type	pos,
		size_type	bytes,
		const completion_handler &	on_cmpl = `completion_handler()`
	)

pure virtual

Schedules an asynchronous read request to the file.

Parameters

buffer	pointer to memory buffer to read into
pos	file position to start read from
bytes	number of bytes to transfer
on_cmpl	I/O completion handler

Returns: request_ptr request object, which can be used to track the status of the operation

Referenced by stxxl::typed_block< RawSize, Type, NRef, MetaInfoType >::read().

virtual request_ptr stxxl::file::awrite	(	void *	buffer,
		offset_type	pos,
		size_type	bytes,
		const completion_handler &	on_cmpl = `completion_handler()`
	)

pure virtual

Schedules an asynchronous write request to the file.

Parameters

buffer	pointer to memory buffer to write from
pos	starting file position to write
bytes	number of bytes to transfer
on_cmpl	I/O completion handler

Returns: request_ptr request object, which can be used to track the status of the operation

Referenced by stxxl::typed_block< RawSize, Type, NRef, MetaInfoType >::write().

virtual void stxxl::file::close_remove ( )

inlinevirtual

close and remove file

Reimplemented in stxxl::wfs_file_base, and stxxl::ufs_file_base.

Definition at line 152 of file file.h.

void stxxl::file::delete_request_ref ( )

inline

decrement referenced requests

Definition at line 192 of file file.h.

virtual void stxxl::file::discard	(	offset_type	offset,
		offset_type	size
	)

inlinevirtual

Discard a region of the file (mark it unused). Some specialized file types may need to know freed regions.

Definition at line 137 of file file.h.

References stxxl::STXXL_UNUSED().

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

inlinevirtual

Definition at line 143 of file file.h.

References stxxl::STXXL_UNUSED().

virtual int stxxl::file::get_allocator_id ( ) const

pure virtual

Returns the file's disk allocator number.

Implemented in stxxl::disk_queued_file.

Referenced by stxxl::block_manager::delete_block(), and stxxl::serving_request::serve().

unsigned int stxxl::file::get_device_id ( ) const

inline

Returns the file's physical device id.

Definition at line 175 of file file.h.

virtual int stxxl::file::get_queue_id ( ) const

pure virtual

Returns the identifier of the file's queue number.

Remarks: Files allocated on the same physical device usually share the same queue, unless there is a common queue (e.g. with linuxaio).

Implemented in stxxl::disk_queued_file.

unsigned_type stxxl::file::get_request_nref ( )

inline

return number of referenced requests

Definition at line 198 of file file.h.

virtual const char* stxxl::file::io_type ( ) const

pure virtual

Identifies the type of I/O implementation.

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

Implemented in stxxl::sim_disk_file, stxxl::wbtl_file, stxxl::fileperblock_file< base_file_type >, stxxl::linuxaio_file, stxxl::wincall_file, stxxl::mem_file, stxxl::wfs_file_base, stxxl::mmap_file, stxxl::ufs_file_base, and stxxl::syscall_file.

Referenced by stxxl::request::check_nref_failed(), stxxl::serving_request::io_type(), and stxxl::request::io_type().

virtual void stxxl::file::lock ( )

pure virtual

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

Implemented in stxxl::wbtl_file, stxxl::fileperblock_file< base_file_type >, stxxl::mem_file, stxxl::wfs_file_base, and stxxl::ufs_file_base.

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

pure virtual

Referenced by stxxl::serving_request::serve().

virtual void stxxl::file::set_size ( offset_type newsize )

pure virtual

Changes the size of the file.

Parameters

newsize new file size

Referenced by stxxl::vector< ValueType >::vector().

virtual offset_type stxxl::file::size ( )

pure virtual

Returns size of the file.

Returns: file size in bytes

Implemented in stxxl::wbtl_file, stxxl::fileperblock_file< base_file_type >, stxxl::mem_file, stxxl::wfs_file_base, and stxxl::ufs_file_base.

static int stxxl::file::truncate	(	const char *	path,
		external_size_type	length
	)

static

truncate a path to given length. Use this only if you dont have a fileio-specific object, which provides truncate().

int stxxl::file::unlink ( const char * path )

static

unlink path from filesystem

Definition at line 18 of file file.cpp.

Member Data Documentation

const unsigned int stxxl::file::DEFAULT_DEVICE_ID = (unsigned int)(-1)

static

Definition at line 85 of file file.h.

Referenced by stxxl::disk_config::fileio_string(), and stxxl::disk_config::parse_line().

const int stxxl::file::DEFAULT_LINUXAIO_QUEUE = -2

static

Definition at line 83 of file file.h.

Referenced by stxxl::disk_config::fileio_string().

const int stxxl::file::DEFAULT_QUEUE = -1

static

Definition at line 82 of file file.h.

Referenced by stxxl::disk_config::fileio_string(), and stxxl::disk_config::parse_line().

unsigned int stxxl::file::m_device_id

protected

The file's physical device id (e.g. used for prefetching sequence calculation)

Definition at line 171 of file file.h.

atomic_counted_object stxxl::file::m_request_ref

protected

count the number of requests referencing this file

Definition at line 182 of file file.h.

const int stxxl::file::NO_ALLOCATOR = -1

static

Definition at line 84 of file file.h.

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

include/stxxl/bits/io/file.h
lib/io/file.cpp

Detailed Description

Public Types

Public Member Functions

Static Public Member Functions

Static Public Attributes

Protected Attributes

Additional Inherited Members

Member Typedef Documentation

Member Enumeration Documentation

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation