#include <File.h>

Inheritance diagram for File:

Public Member Functions
	File ()
	Create an uninitialized file. More...

	File (FileSystem fs, const char path, int flags=O_RDONLY)
	Create a file on a filesystem. More...

virtual	~File ()
	Destroy a file. More...

virtual int	open (FileSystem fs, const char path, int flags=O_RDONLY)
	Open a file on the filesystem. More...

virtual int	close ()
	Close a file. More...

virtual ssize_t	read (void *buffer, size_t size)
	Read the contents of a file into a buffer. More...

virtual ssize_t	write (const void *buffer, size_t size)
	Write the contents of a buffer to a file. More...

virtual int	sync ()
	Flush any buffers associated with the file. More...

virtual int	isatty ()
	Check if the file in an interactive terminal device. More...

virtual off_t	seek (off_t offset, int whence=SEEK_SET)
	Move the file position to a given offset from from a given location. More...

virtual off_t	tell ()
	Get the file position of the file. More...

virtual void	rewind ()
	Rewind the file position to the beginning of the file. More...

virtual off_t	size ()
	Get the size of the file. More...

virtual int	truncate (off_t length)
	Truncate or extend a file. More...

virtual int	set_blocking (bool blocking)
	Set blocking or nonblocking mode of the file operation like read/write. More...

virtual bool	is_blocking () const
	Check current blocking or nonblocking mode for file operations. More...

virtual int	enable_input (bool enabled)
	Enable or disable input. More...

virtual int	enable_output (bool enabled)
	Enable or disable output. More...

virtual short	poll (short events) const
	Check for poll event flags You can use or ignore the input parameter. More...

bool	writable () const
	Definition depends on the subclass implementing FileHandle. More...

bool	readable () const
	Definition depends on the subclass implementing FileHandle. More...

virtual void	sigio (Callback< void()> func)
	Register a callback on state change of the file. More...

Detailed Description

File class.

Definition at line 31 of file File.h.

Constructor & Destructor Documentation

File ( )

Create an uninitialized file.

Must call open to initialize the file on a file system

File	(	FileSystem *	fs,
		const char *	path,
		int	flags = `O_RDONLY`
	)

Create a file on a filesystem.

Creates and opens a file on a filesystem

Parameters

fs	Filesystem as target for the file
path	The name of the file to open
flags	The flags to open the file in, one of O_RDONLY, O_WRONLY, O_RDWR, bitwise or'd with one of O_CREAT, O_TRUNC, O_APPEND

virtual ~File ( )

virtual

Destroy a file.

Closes file if the file is still open

Member Function Documentation

virtual int close ( )

virtual

Close a file.

Returns: 0 on success, negative error code on failure

Implements FileHandle.

virtual int enable_input ( bool enabled )

virtualinherited

Enable or disable input.

Control enabling of device for input. This is primarily intended for temporary power-saving; the overall ability of the device to operate for input and/or output may be fixed at creation time, but this call can allow input to be temporarily disabled to permit power saving without losing device state.

Parameters

enabled true to enable input, false to disable.

Returns: 0 on success; Negative error code on failure

Reimplemented in BufferedSerial.

Definition at line 192 of file FileHandle.h.

virtual int enable_output ( bool enabled )

virtualinherited

Enable or disable output.

Control enabling of device for output. This is primarily intended for temporary power-saving; the overall ability of the device to operate for input and/or output may be fixed at creation time, but this call can allow output to be temporarily disabled to permit power saving without losing device state.

Parameters

enabled true to enable output, false to disable.

Returns: 0 on success; Negative error code on failure

Reimplemented in BufferedSerial.

Definition at line 210 of file FileHandle.h.

virtual bool is_blocking ( ) const

virtualinherited

Check current blocking or nonblocking mode for file operations.

Returns: true for blocking mode, false for nonblocking mode.

Reimplemented in BufferedSerial.

Definition at line 174 of file FileHandle.h.

virtual int isatty ( )

virtual

Check if the file in an interactive terminal device.

Returns: True if the file is a terminal

Reimplemented from FileHandle.

virtual int open	(	FileSystem *	fs,
		const char *	path,
		int	flags = `O_RDONLY`
	)

virtual

Open a file on the filesystem.

Parameters

fs	Filesystem as target for the file
path	The name of the file to open
flags	The flags to open the file in, one of O_RDONLY, O_WRONLY, O_RDWR, bitwise or'd with one of O_CREAT, O_TRUNC, O_APPEND

Returns: 0 on success, negative error code on failure

virtual short poll ( short events ) const

virtualinherited

Check for poll event flags You can use or ignore the input parameter.

You can return all events or check just the events listed in events. Call is nonblocking - returns instantaneous state of events. Whenever an event occurs, the derived class should call the sigio() callback).

Parameters

events bitmask of poll events we're interested in - POLLIN/POLLOUT etc.

Returns: bitmask of poll events that have occurred.

Reimplemented in UnbufferedSerial, and BufferedSerial.

Definition at line 225 of file FileHandle.h.

virtual ssize_t read	(	void *	buffer,
		size_t	size
	)

virtual

Read the contents of a file into a buffer.

Parameters

buffer	The buffer to read in to
size	The number of bytes to read

Returns: The number of bytes read, 0 at end of file, negative error on failure

Implements FileHandle.

bool readable ( ) const

inherited

Definition depends on the subclass implementing FileHandle.

For example, if the FileHandle is of type Stream, readable() could return true when there is something available to read.

Returns: true when there is something available to read.

Definition at line 248 of file FileHandle.h.

virtual void rewind ( )

virtual

Rewind the file position to the beginning of the file.

Note: This is equivalent to file_seek(file, 0, FS_SEEK_SET)

Reimplemented from FileHandle.

virtual off_t seek	(	off_t	offset,
		int	whence = `SEEK_SET`
	)

virtual

Move the file position to a given offset from from a given location.

Parameters

offset	The offset from whence to move to
whence	The start of where to seek SEEK_SET to start from beginning of file, SEEK_CUR to start from current position in file, SEEK_END to start from end of file

Returns: The new offset of the file

Implements FileHandle.

virtual int set_blocking ( bool blocking )

virtualinherited

Set blocking or nonblocking mode of the file operation like read/write.

Definition depends on the subclass implementing FileHandle. The default is blocking.

Parameters

blocking true for blocking mode, false for nonblocking mode.

Returns: 0 on success; Negative error code on failure

Reimplemented in BufferedSerial.

Definition at line 165 of file FileHandle.h.

virtual void sigio ( Callback< void()> func )

virtualinherited

Register a callback on state change of the file.

The specified callback will be called on state changes such as when the file can be written to or read from.

The callback may be called in an interrupt context and should not perform expensive operations.

Note! This is not intended as an attach-like asynchronous API, but rather as a building block for constructing such functionality.

The exact timing of when the registered function is called is not guaranteed and is susceptible to change. It should be used as a cue to make read/write/poll calls to find the current state.

Parameters

func	Function to call on state change

Reimplemented in BufferedSerial.

Definition at line 270 of file FileHandle.h.

virtual off_t size ( )

virtual

Get the size of the file.

Returns: Size of the file in bytes

Reimplemented from FileHandle.

virtual int sync ( )

virtual

Flush any buffers associated with the file.

Returns: 0 on success, negative error code on failure

Reimplemented from FileHandle.

virtual off_t tell ( )

virtual

Get the file position of the file.

Returns: The current offset in the file

Reimplemented from FileHandle.

virtual int truncate ( off_t length )

virtual

Truncate or extend a file.

The file's length is set to the specified value. The seek pointer is not changed. If the file is extended, the extended area appears as if it were zero-filled.

Parameters

length The requested new length for the file

Returns: Zero on success, negative error code on failure

Reimplemented from FileHandle.

bool writable ( ) const

inherited

Definition depends on the subclass implementing FileHandle.

For example, if the FileHandle is of type Stream, writable() could return true when there is ample buffer space available for write() calls.

Returns: true if the FileHandle is writable.

Definition at line 237 of file FileHandle.h.

virtual ssize_t write	(	const void *	buffer,
		size_t	size
	)

virtual

Write the contents of a buffer to a file.

Parameters

buffer	The buffer to write from
size	The number of bytes to write

Returns: The number of bytes written, negative error on failure

Implements FileHandle.

Public Member Functions

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation

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