#include "distortos/FileSystem/File.hpp"

Inheritance diagram for distortos::File:

Public Types
enum	Whence { Whence::beginning, Whence::current, Whence::end }
	seek() mode of operation More...

Public Member Functions
virtual	~File ()=default
	File's destructor. More...

virtual int	close ()=0
	Closes file. More...

virtual std::pair< int, off_t >	getPosition ()=0
	Returns current file offset. More...

virtual std::pair< int, off_t >	getSize ()=0
	Returns size of file. More...

virtual int	getStatus (struct stat &status)=0
	Returns status of file. More...

virtual std::pair< int, bool >	isATerminal ()=0
	Tells whether the file is a terminal. More...

virtual void	lock ()=0
	Locks the file for exclusive use by current thread. More...

virtual std::pair< int, size_t >	read (void *buffer, size_t size)=0
	Reads data from file. More...

virtual int	rewind ()=0
	Resets current file offset. More...

virtual std::pair< int, off_t >	seek (Whence whence, off_t offset)=0
	Moves file offset. More...

virtual int	synchronize ()=0
	Synchronizes state of a file, ensuring all cached writes are finished. More...

virtual void	unlock ()=0
	Unlocks the file which was previously locked by current thread. More...

virtual std::pair< int, size_t >	write (const void *buffer, size_t size)=0
	Writes data to file. More...

	File (const File &)=delete

File &	operator= (const File &)=delete

Detailed Description

File class is an interface for a file.

Member Enumeration Documentation

◆ Whence

enum distortos::File::Whence

strong

seek() mode of operation

Enumerator
beginning	set file offset to provided argument, similar to `SEEK_SET`
current	set file offset to its current value plus provided argument, similar to `SEEK_CUR`
end	set file offset to the size of the file plus provided argument, similar to `SEEK_END`

Constructor & Destructor Documentation

◆ ~File()

virtual distortos::File::~File ( )

virtualdefault

File's destructor.

Precondition: File is closed.

Member Function Documentation

◆ close()

virtual int distortos::File::close ( )

pure virtual

Closes file.

Similar to close()

Note: Even if error code is returned, the file must not be used.

Precondition: File is opened.

Postcondition: File is closed.

Returns: 0 on success, error code otherwise

Implemented in distortos::Littlefs1File.

◆ getPosition()

virtual std::pair<int, off_t> distortos::File::getPosition ( )

pure virtual

Returns current file offset.

Similar to ftello()

Precondition: File is opened.

Returns: pair with return code (0 on success, error code otherwise) and current file offset, bytes

Implemented in distortos::Littlefs1File.

◆ getSize()

virtual std::pair<int, off_t> distortos::File::getSize ( )

pure virtual

Returns size of file.

Precondition: File is opened.

Returns: pair with return code (0 on success, error code otherwise) and size of file, bytes

Implemented in distortos::Littlefs1File.

◆ getStatus()

virtual int distortos::File::getStatus ( struct stat & status )

pure virtual

Returns status of file.

Similar to fstat()

Precondition: File is opened.

Parameters

[out] status is a reference to stat struct into which status of file will be written

Returns: 0 on success, error code otherwise

Implemented in distortos::Littlefs1File.

◆ isATerminal()

virtual std::pair<int, bool> distortos::File::isATerminal ( )

pure virtual

Tells whether the file is a terminal.

Similar to isatty()

Precondition: File is opened.

Returns: pair with return code (0 on success, error code otherwise) and bool telling whether the file is a terminal (true) or not (false)

Implemented in distortos::Littlefs1File.

◆ lock()

virtual void distortos::File::lock ( )

pure virtual

Locks the file for exclusive use by current thread.

When the object is locked, any call to any member function from other thread will be blocked until the object is unlocked. Locking is optional, but may be useful when more than one operation must be done atomically.

Note: Locks are recursive.

Warning: This function must not be called from interrupt context!

Precondition: The number of recursive locks of file is less than 65535.

Postcondition: File is locked.

Implemented in distortos::Littlefs1File.

◆ read()

virtual std::pair<int, size_t> distortos::File::read	(	void *	buffer,
		size_t	size
	)

pure virtual

Reads data from file.

◆ rewind()

virtual int distortos::File::rewind ( )

pure virtual

Resets current file offset.

Similar to rewind()

Precondition: File is opened.

Returns: 0 on success, error code otherwise

Implemented in distortos::Littlefs1File.

◆ seek()

virtual std::pair<int, off_t> distortos::File::seek	(	Whence	whence,
		off_t	offset
	)

pure virtual

Moves file offset.

Similar to lseek()

Precondition: File is opened.

Parameters

[in]	whence	selects the mode of operation: `Whence::beginning` will set file offset to offset, `Whence::current` will set file offset to its current value plus offset, `Whence::end` will set file offset to the size of the file plus offset
[in]	offset	is the value of offset, bytes

Returns

pair with return code (0 on success, error code otherwise) and current file offset, bytes; error codes:

EINVAL - resulting file offset would be negative;

Implemented in distortos::Littlefs1File.

◆ synchronize()

virtual int distortos::File::synchronize ( )

pure virtual

Synchronizes state of a file, ensuring all cached writes are finished.

Similar to fsync()

Precondition: File is opened.

Returns: 0 on success, error code otherwise

Implemented in distortos::Littlefs1File.

◆ unlock()

virtual void distortos::File::unlock ( )

pure virtual

Unlocks the file which was previously locked by current thread.

Note: Locks are recursive.

Warning: This function must not be called from interrupt context!

Precondition: This function is called by the thread that locked the file.

Implemented in distortos::Littlefs1File.

◆ write()

virtual std::pair<int, size_t> distortos::File::write	(	const void *	buffer,
		size_t	size
	)

pure virtual

Writes data to file.

Similar to write()

Precondition: File is opened.; buffer is valid.

Parameters

[in]	buffer	is the buffer with data that will be written, must be valid
[in]	size	is the size of buffer, bytes

Returns

pair with return code (0 on success, error code otherwise) and number of written bytes (valid even when error code is returned); error codes:

ENOSPC - no space left on the device containing the file;

Implemented in distortos::Littlefs1File.

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

include/distortos/FileSystem/File.hpp

[out]	buffer	is the buffer into which the data will be read, must be valid
[in]	size	is the size of buffer, bytes

Public Types

Public Member Functions

Detailed Description

Member Enumeration Documentation

◆ Whence

Constructor & Destructor Documentation

◆ ~File()

Member Function Documentation

◆ close()

◆ getPosition()

◆ getSize()

◆ getStatus()

◆ isATerminal()

◆ lock()

◆ read()

◆ rewind()

◆ seek()

◆ synchronize()

◆ unlock()

◆ write()