A reference-counted handle to a file descriptor. More...

#include <file_descriptor.hh>

Inheritance diagram for FileDescriptor:

[legend]

Classes
class	FDWrapper
	A handle on a kernel file descriptor. More...

Public Member Functions
	FileDescriptor (const int fd)
	Construct from a file descriptor number returned by the kernel. More...

	~FileDescriptor ()=default
	Free the std::shared_ptr; the FDWrapper destructor calls close() when the refcount goes to zero. More...

void	close ()
	Close the underlying file descriptor. More...

FileDescriptor	duplicate () const
	Copy a FileDescriptor explicitly, increasing the FDWrapper refcount. More...

std::string	read (const size_t limit=std::numeric_limits< size_t >::max())
	Read up to `limit` bytes. More...

void	read (std::string &str, const size_t limit=std::numeric_limits< size_t >::max())
	Read up to `limit` bytes into `str` (caller can allocate storage) More...

void	set_blocking (const bool blocking_state)
	Set blocking(true) or non-blocking(false) More...

size_t	write (BufferViewList buffer, const bool write_all=true)
	Write a buffer (or list of buffers), possibly blocking until all is written. More...

size_t	write (const char *str, const bool write_all=true)
	Write a string, possibly blocking until all is written. More...

size_t	write (const std::string &str, const bool write_all=true)
	Write a string, possibly blocking until all is written. More...

FDWrapper accessors
int	fd_num () const
	underlying descriptor number More...

bool	eof () const
	EOF flag state. More...

bool	closed () const
	closed flag state More...

unsigned int	read_count () const
	number of reads More...

unsigned int	write_count () const
	number of writes More...

Copy/move constructor/assignment operators
FileDescriptor can be moved, but cannot be copied (but see duplicate())
	FileDescriptor (const FileDescriptor &other)=delete
	copy construction is forbidden More...

FileDescriptor &	operator= (const FileDescriptor &other)=delete
	copy assignment is forbidden More...

	FileDescriptor (FileDescriptor &&other)=default
	move construction is allowed More...

FileDescriptor &	operator= (FileDescriptor &&other)=default
	move assignment is allowed More...

Private Member Functions
	FileDescriptor (std::shared_ptr< FDWrapper > other_shared_ptr)
	Private constructor used by duplicate() More...

Private Attributes
std::shared_ptr< FDWrapper >	_internal_fd
	A reference-counted handle to a shared FDWrapper. More...

Detailed Description

A reference-counted handle to a file descriptor.

In addition, FileDescriptor tracks EOF state and calls to FileDescriptor::read and FileDescriptor::write, which EventLoop uses to detect busy loop conditions.

For an example of FileDescriptor use, see the EventLoop class documentation.

Definition at line 12 of file file_descriptor.hh.

Constructor & Destructor Documentation

◆ FileDescriptor() [1/4]

FileDescriptor::FileDescriptor ( std::shared_ptr< FDWrapper > other_shared_ptr )

explicitprivate

Private constructor used by duplicate()

Definition at line 42 of file file_descriptor.cc.

◆ FileDescriptor() [2/4]

FileDescriptor::FileDescriptor ( const int fd )

explicit

Construct from a file descriptor number returned by the kernel.

Parameters

[in] fd is the file descriptor number returned by open(2) or similar

Definition at line 39 of file file_descriptor.cc.

◆ ~FileDescriptor()

FileDescriptor::~FileDescriptor ( )

default

Free the std::shared_ptr; the FDWrapper destructor calls close() when the refcount goes to zero.

◆ FileDescriptor() [3/4]

FileDescriptor::FileDescriptor ( const FileDescriptor & other )

delete

copy construction is forbidden

◆ FileDescriptor() [4/4]

FileDescriptor::FileDescriptor ( FileDescriptor && other )

default

move construction is allowed

Member Function Documentation

◆ close()

void FileDescriptor::close ( )

inline

Close the underlying file descriptor.

Definition at line 74 of file file_descriptor.hh.

◆ closed()

bool FileDescriptor::closed ( ) const

inline

closed flag state

Definition at line 92 of file file_descriptor.hh.

◆ duplicate()

FileDescriptor FileDescriptor::duplicate ( ) const

Copy a FileDescriptor explicitly, increasing the FDWrapper refcount.

Returns: a copy of this FileDescriptor

Definition at line 45 of file file_descriptor.cc.

◆ eof()

bool FileDescriptor::eof ( ) const

inline

EOF flag state.

Definition at line 89 of file file_descriptor.hh.

◆ fd_num()

int FileDescriptor::fd_num ( ) const

inline

underlying descriptor number

Definition at line 86 of file file_descriptor.hh.

◆ operator=() [1/2]

FileDescriptor& FileDescriptor::operator= ( const FileDescriptor & other )

delete

copy assignment is forbidden

◆ operator=() [2/2]

FileDescriptor& FileDescriptor::operator= ( FileDescriptor && other )

default

move assignment is allowed

◆ read() [1/2]

std::string FileDescriptor::read ( const size_t limit = std::numeric_limits< size_t >::max() )

Read up to limit bytes.

◆ read() [2/2]

void FileDescriptor::read	(	std::string &	str,
		const size_t	limit = `std::numeric_limits< size_t >::max()`
	)

Read up to limit bytes into str (caller can allocate storage)

◆ read_count()

unsigned int FileDescriptor::read_count ( ) const

inline

number of reads

Definition at line 95 of file file_descriptor.hh.

◆ set_blocking()

void FileDescriptor::set_blocking ( const bool blocking_state )

Set blocking(true) or non-blocking(false)

Definition at line 101 of file file_descriptor.cc.

◆ write() [1/3]

size_t FileDescriptor::write	(	BufferViewList	buffer,
		const bool	write_all = `true`
	)

Write a buffer (or list of buffers), possibly blocking until all is written.

Definition at line 76 of file file_descriptor.cc.

◆ write() [2/3]

size_t FileDescriptor::write	(	const char *	str,
		const bool	write_all = `true`
	)

inline

Write a string, possibly blocking until all is written.

Definition at line 65 of file file_descriptor.hh.

◆ write() [3/3]

size_t FileDescriptor::write	(	const std::string &	str,
		const bool	write_all = `true`
	)

inline

Write a string, possibly blocking until all is written.

Definition at line 68 of file file_descriptor.hh.

◆ write_count()

unsigned int FileDescriptor::write_count ( ) const

inline

number of writes

Definition at line 98 of file file_descriptor.hh.

Member Data Documentation

◆ _internal_fd

std::shared_ptr<FDWrapper> FileDescriptor::_internal_fd

private

A reference-counted handle to a shared FDWrapper.

Definition at line 42 of file file_descriptor.hh.

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

/home/cs144/sponge/libsponge/util/file_descriptor.hh
/home/cs144/sponge/libsponge/util/file_descriptor.cc

Classes

Public Member Functions

Private Member Functions

Private Attributes

Detailed Description

Constructor & Destructor Documentation

◆ FileDescriptor() [1/4]

◆ FileDescriptor() [2/4]

◆ ~FileDescriptor()

◆ FileDescriptor() [3/4]

◆ FileDescriptor() [4/4]

Member Function Documentation

◆ close()

◆ closed()

◆ duplicate()

◆ eof()

◆ fd_num()

◆ operator=() [1/2]

◆ operator=() [2/2]

◆ read() [1/2]

◆ read() [2/2]

◆ read_count()

◆ set_blocking()

◆ write() [1/3]

◆ write() [2/3]

◆ write() [3/3]

◆ write_count()

Member Data Documentation

◆ _internal_fd