#include <userver/engine/io/fd_poller.hpp>

Detailed Description

Low-level poller that can wait for read, write, and read/write operations on a file descriptor. It does not provide read/write operations.

Note: FdPoller is not thread safe and its methods must not be called from multiple threads simultaneously.

Definition at line 28 of file fd_poller.hpp.

Public Types
enum class	Kind { kRead = 1 , kWrite = 2 , kReadWrite = 3 }
	Operation kind to wait for. More...

Public Member Functions
	FdPoller (const FdPoller &)=delete

	FdPoller (FdPoller &&)=delete

FdPoller &	operator= (const FdPoller &)=delete

FdPoller &	operator= (FdPoller &&)=delete

	operator bool () const noexcept
	The same as `IsValid()`.

bool	IsValid () const noexcept
	Whether the file descriptor is valid.

int	GetFd () const
	If IsValid(), get file descriptor.

void	Invalidate ()

void	Reset (int fd, Kind kind)

std::optional< Kind >	Wait (Deadline)

void	ResetReady () noexcept
	Reset "ready" flag for WaitAny().

std::optional< FdPoller::Kind >	GetReady () noexcept

Member Enumeration Documentation

◆ Kind

enum class engine::io::FdPoller::Kind

strong

Operation kind to wait for.

Enumerator
kWrite	< wait for read availability
kReadWrite	< wait for write availability

Definition at line 31 of file fd_poller.hpp.

Member Function Documentation

◆ GetReady()

std::optional< FdPoller::Kind > engine::io::FdPoller::GetReady ( )

noexcept

Get event kind that was triggered on this poller. Resets "ready" flag.

◆ Invalidate()

void engine::io::FdPoller::Invalidate ( )

When you're done with fd, call Invalidate(). It unregisters the fd, after that you have to call close(2) by yourself. After Invalidate() you may not call Wait().

◆ Reset()

void engine::io::FdPoller::Reset	(	int	fd,
		Kind	kind )

Setup fd and kind to wait for. After Reset() you may call Wait(). FdPoller does not take the ownership of fd, you still have to close fd when you're done.

◆ Wait()

std::optional< Kind > engine::io::FdPoller::Wait ( Deadline )

Wait for an event kind that was passed in the latest Reset() call. If the operation (read/write) can already be handled, Wait() returns immediately. You have to call Reset() at least once before call to Wait().

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

userver/engine/io/fd_poller.hpp