foobar2000_io::file Class Reference

#include <filesystem.h>

Inheritance diagram for foobar2000_io::file:

List of all members.

Public Types

enum t_seek_mode { seek_from_beginning = 0, seek_from_current = 1, seek_from_eof = 2 }

Seeking mode constants. Note: these are purposedly defined to same values as standard C SEEK_* constants. More...

typedef file t_interface

typedef service_base t_interface_parent

Public Member Functions

virtual t_filesize get_size (abort_callback &p_abort)=0

virtual t_filesize get_position (abort_callback &p_abort)=0

virtual void resize (t_filesize p_size, abort_callback &p_abort)=0

virtual void seek (t_filesize p_position, abort_callback &p_abort)=0

virtual void seek_ex (t_sfilesize p_position, t_seek_mode p_mode, abort_callback &p_abort)

virtual bool can_seek ()=0

Returns whether the file is seekable or not. If can_seek() returns false, all seek() or seek_ex() calls will fail; reopen() is still usable on nonseekable streams.

virtual bool get_content_type (pfc::string_base &p_out)=0

virtual bool is_in_memory ()

Hint, returns whether the file is already fully buffered into memory.

virtual void on_idle (abort_callback &p_abort)

virtual t_filetimestamp get_timestamp (abort_callback &p_abort)

virtual void reopen (abort_callback &p_abort)=0

virtual bool is_remote ()=0

Indicates whether the file is a remote resource and non-sequential access may be slowed down by lag. This is typically returns to true on non-seekable sources but may also return true on seekable sources indicating that seeking is supported but will be relatively slow.

t_filestats get_stats (abort_callback &p_abort)

Retrieves file stats structure. Usese get_size() and get_timestamp().

bool is_eof (abort_callback &p_abort)

Returns whether read/write cursor position is at the end of file.

void truncate (t_filesize p_position, abort_callback &p_abort)

Truncates file to specified size (while preserving read/write cursor position if possible); uses set_eof().

void set_eof (abort_callback &p_abort)

Truncates the file at current read/write cursor position.

t_filesize get_size_ex (abort_callback &p_abort)

Helper; retrieves size of the file. If size is not available (get_size() returns filesize_invalid), throws exception_io_no_length.

t_filesize get_remaining (abort_callback &p_abort)

Helper; retrieves amount of bytes between read/write cursor position and end of file. Fails when length can't be determined.

void ensure_seekable ()

Helper; throws exception_io_object_not_seekable if file is not seekable.

void ensure_local ()

Helper; throws exception_io_object_is_remote if the file is remote.

Static Public Member Functions

static t_filesize g_transfer (stream_reader *src, stream_writer *dst, t_filesize bytes, abort_callback &p_abort)

static void g_transfer_object (stream_reader *src, stream_writer *dst, t_filesize bytes, abort_callback &p_abort)

Helper; transfers specified number of bytes between streams. Throws exception if requested number of bytes could not be read (EOF).

static void g_transfer_file (const service_ptr_t< file > &p_from, const service_ptr_t< file > &p_to, abort_callback &p_abort)

Helper; transfers entire file content from one file to another, erasing previous content.

static t_filesize g_transfer (service_ptr_t< file > p_src, service_ptr_t< file > p_dst, t_filesize p_bytes, abort_callback &p_abort)

Helper; improved performance over g_transfer on streams (avoids disk fragmentation when transferring large blocks).

static void g_transfer_object (service_ptr_t< file > p_src, service_ptr_t< file > p_dst, t_filesize p_bytes, abort_callback &p_abort)

Helper; improved performance over g_transfer_file on streams (avoids disk fragmentation when transferring large blocks).

Static Public Attributes

static const GUID class_guid

Detailed Description

A class providing abstraction for an open file object, with reading/writing/seeking methods. See also: stream_reader, stream_writer (which it inherits read/write methods from).
Error handling: all methods may throw exception_io or one of derivatives on failure; exception_aborted when abort_callback is signaled.

Member Typedef Documentation

typedef file foobar2000_io::file::t_interface

Reimplemented from service_base.

Reimplemented in foobar2000_io::file_dynamicinfo.

typedef service_base foobar2000_io::file::t_interface_parent

Reimplemented in foobar2000_io::file_dynamicinfo.

Member Enumeration Documentation

enum foobar2000_io::file::t_seek_mode

Seeking mode constants. Note: these are purposedly defined to same values as standard C SEEK_* constants.

Enumerator:

seek_from_beginning	Seek relative to beginning of file (same as seeking to absolute offset).
seek_from_current	Seek relative to current position.
seek_from_eof	Seek relative to end of file.

Member Function Documentation

virtual t_filesize foobar2000_io::file::get_size ( abort_callback & p_abort ) [pure virtual]

Retrieves size of the file.

Parameters:

p_abort

abort_callback object signaling user aborting the operation.

Returns:: File size on success; filesize_invalid if unknown (nonseekable stream etc).

virtual t_filesize foobar2000_io::file::get_position ( abort_callback & p_abort ) [pure virtual]

Retrieves read/write cursor position in the file. In case of non-seekable stream, this should return number of bytes read so far since open/reopen call.

Parameters:

p_abort

abort_callback object signaling user aborting the operation.

Returns:: Read/write cursor position

virtual void foobar2000_io::file::resize	(	t_filesize	p_size,
		abort_callback &	p_abort
	)			`[pure virtual]`

Resizes file to specified size in bytes.

Parameters:

p_abort

abort_callback object signaling user aborting the operation.

virtual void foobar2000_io::file::seek	(	t_filesize	p_position,
		abort_callback &	p_abort
	)			`[pure virtual]`

Sets read/write cursor position to specific offset.

Parameters:

	p_position	position to seek to.
	p_abort	abort_callback object signaling user aborting the operation.

virtual void foobar2000_io::file::seek_ex	(	t_sfilesize	p_position,
		t_seek_mode	p_mode,
		abort_callback &	p_abort
	)			`[virtual]`

Sets read/write cursor position to specific offset; extended form allowing seeking relative to current position or to end of file.

Parameters:

	p_position	Position to seek to; interpretation of this value depends on p_mode parameter.
	p_mode	Seeking mode; see t_seek_mode enum values for further description.
	p_abort	abort_callback object signaling user aborting the operation.

virtual bool foobar2000_io::file::can_seek ( ) [pure virtual]

Returns whether the file is seekable or not. If can_seek() returns false, all seek() or seek_ex() calls will fail; reopen() is still usable on nonseekable streams.

virtual bool foobar2000_io::file::get_content_type ( pfc::string_base & p_out ) [pure virtual]

Retrieves mime type of the file.

Parameters:

p_out

Receives content type string on success.

virtual bool foobar2000_io::file::is_in_memory ( ) [inline, virtual]

Hint, returns whether the file is already fully buffered into memory.

virtual void foobar2000_io::file::on_idle ( abort_callback & p_abort ) [inline, virtual]

Optional, called by owner thread before sleeping.

Parameters:

p_abort

abort_callback object signaling user aborting the operation.

virtual t_filetimestamp foobar2000_io::file::get_timestamp ( abort_callback & p_abort ) [inline, virtual]

Retrieves last modification time of the file.

Parameters:

p_abort

abort_callback object signaling user aborting the operation.

Returns:: Last modification time o fthe file; filetimestamp_invalid if N/A.

virtual void foobar2000_io::file::reopen ( abort_callback & p_abort ) [pure virtual]

Resets non-seekable stream, or seeks to zero on seekable file.

Parameters:

p_abort

abort_callback object signaling user aborting the operation.

virtual bool foobar2000_io::file::is_remote ( ) [pure virtual]

Indicates whether the file is a remote resource and non-sequential access may be slowed down by lag. This is typically returns to true on non-seekable sources but may also return true on seekable sources indicating that seeking is supported but will be relatively slow.

t_filestats foobar2000_io::file::get_stats ( abort_callback & p_abort )

Retrieves file stats structure. Usese get_size() and get_timestamp().

bool foobar2000_io::file::is_eof ( abort_callback & p_abort )

Returns whether read/write cursor position is at the end of file.

void foobar2000_io::file::truncate	(	t_filesize	p_position,
		abort_callback &	p_abort
	)

Truncates file to specified size (while preserving read/write cursor position if possible); uses set_eof().

void foobar2000_io::file::set_eof ( abort_callback & p_abort ) [inline]

Truncates the file at current read/write cursor position.

t_filesize foobar2000_io::file::get_size_ex ( abort_callback & p_abort )

Helper; retrieves size of the file. If size is not available (get_size() returns filesize_invalid), throws exception_io_no_length.

t_filesize foobar2000_io::file::get_remaining ( abort_callback & p_abort )

Helper; retrieves amount of bytes between read/write cursor position and end of file. Fails when length can't be determined.

void foobar2000_io::file::ensure_seekable ( )

Helper; throws exception_io_object_not_seekable if file is not seekable.

void foobar2000_io::file::ensure_local ( )

Helper; throws exception_io_object_is_remote if the file is remote.

static t_filesize foobar2000_io::file::g_transfer	(	stream_reader *	src,
		stream_writer *	dst,
		t_filesize	bytes,
		abort_callback &	p_abort
	)			`[static]`

Helper; transfers specified number of bytes between streams.

Returns:: number of bytes actually transferred. May be less than requested if e.g. EOF is reached.

static void foobar2000_io::file::g_transfer_object	(	stream_reader *	src,
		stream_writer *	dst,
		t_filesize	bytes,
		abort_callback &	p_abort
	)			`[static]`

Helper; transfers specified number of bytes between streams. Throws exception if requested number of bytes could not be read (EOF).

static void foobar2000_io::file::g_transfer_file	(	const service_ptr_t< file > &	p_from,
		const service_ptr_t< file > &	p_to,
		abort_callback &	p_abort
	)			`[static]`

Helper; transfers entire file content from one file to another, erasing previous content.

static t_filesize foobar2000_io::file::g_transfer	(	service_ptr_t< file >	p_src,
		service_ptr_t< file >	p_dst,
		t_filesize	p_bytes,
		abort_callback &	p_abort
	)			`[static]`

Helper; improved performance over g_transfer on streams (avoids disk fragmentation when transferring large blocks).

static void foobar2000_io::file::g_transfer_object	(	service_ptr_t< file >	p_src,
		service_ptr_t< file >	p_dst,
		t_filesize	p_bytes,
		abort_callback &	p_abort
	)			`[static]`

Helper; improved performance over g_transfer_file on streams (avoids disk fragmentation when transferring large blocks).

Member Data Documentation

const GUID file::class_guid [static]

Initial value:

 
{ 0xb2f9fc40, 0x3e55, 0x4b23, { 0xa2, 0xc9, 0x22, 0xba, 0xad, 0x87, 0x95, 0xb1 } }

Reimplemented in foobar2000_io::file_dynamicinfo.

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

foobar2000/SDK/filesystem.h
foobar2000/SDK/guids.cpp


Public Types
enum	t_seek_mode { seek_from_beginning = 0, seek_from_current = 1, seek_from_eof = 2 }
	Seeking mode constants. Note: these are purposedly defined to same values as standard C SEEK_* constants. More...
typedef file	t_interface
typedef service_base	t_interface_parent
Public Member Functions
virtual t_filesize	get_size (abort_callback &p_abort)=0
virtual t_filesize	get_position (abort_callback &p_abort)=0
virtual void	resize (t_filesize p_size, abort_callback &p_abort)=0
virtual void	seek (t_filesize p_position, abort_callback &p_abort)=0
virtual void	seek_ex (t_sfilesize p_position, t_seek_mode p_mode, abort_callback &p_abort)
virtual bool	can_seek ()=0
	Returns whether the file is seekable or not. If can_seek() returns false, all seek() or seek_ex() calls will fail; reopen() is still usable on nonseekable streams.
virtual bool	get_content_type (pfc::string_base &p_out)=0
virtual bool	is_in_memory ()
	Hint, returns whether the file is already fully buffered into memory.
virtual void	on_idle (abort_callback &p_abort)
virtual t_filetimestamp	get_timestamp (abort_callback &p_abort)
virtual void	reopen (abort_callback &p_abort)=0
virtual bool	is_remote ()=0
	Indicates whether the file is a remote resource and non-sequential access may be slowed down by lag. This is typically returns to true on non-seekable sources but may also return true on seekable sources indicating that seeking is supported but will be relatively slow.
t_filestats	get_stats (abort_callback &p_abort)
	Retrieves file stats structure. Usese get_size() and get_timestamp().
bool	is_eof (abort_callback &p_abort)
	Returns whether read/write cursor position is at the end of file.
void	truncate (t_filesize p_position, abort_callback &p_abort)
	Truncates file to specified size (while preserving read/write cursor position if possible); uses set_eof().
void	set_eof (abort_callback &p_abort)
	Truncates the file at current read/write cursor position.
t_filesize	get_size_ex (abort_callback &p_abort)
	Helper; retrieves size of the file. If size is not available (get_size() returns filesize_invalid), throws exception_io_no_length.
t_filesize	get_remaining (abort_callback &p_abort)
	Helper; retrieves amount of bytes between read/write cursor position and end of file. Fails when length can't be determined.
void	ensure_seekable ()
	Helper; throws exception_io_object_not_seekable if file is not seekable.
void	ensure_local ()
	Helper; throws exception_io_object_is_remote if the file is remote.
Static Public Member Functions
static t_filesize	g_transfer (stream_reader src, stream_writer dst, t_filesize bytes, abort_callback &p_abort)
static void	g_transfer_object (stream_reader src, stream_writer dst, t_filesize bytes, abort_callback &p_abort)
	Helper; transfers specified number of bytes between streams. Throws exception if requested number of bytes could not be read (EOF).
static void	g_transfer_file (const service_ptr_t< file > &p_from, const service_ptr_t< file > &p_to, abort_callback &p_abort)
	Helper; transfers entire file content from one file to another, erasing previous content.
static t_filesize	g_transfer (service_ptr_t< file > p_src, service_ptr_t< file > p_dst, t_filesize p_bytes, abort_callback &p_abort)
	Helper; improved performance over g_transfer on streams (avoids disk fragmentation when transferring large blocks).
static void	g_transfer_object (service_ptr_t< file > p_src, service_ptr_t< file > p_dst, t_filesize p_bytes, abort_callback &p_abort)
	Helper; improved performance over g_transfer_file on streams (avoids disk fragmentation when transferring large blocks).
Static Public Attributes
static const GUID	class_guid