RAII wrapper for the registration of a FD in a Poller. More...

#include <dfx-fdwatch/PollerFd.hpp>

Public Member Functions
	PollerFd () noexcept=default
	Constructs an empty handle with no poller association and no FD.
	PollerFd (Utils::OwnedFd fd) noexcept
	Takes ownership of `fd` but do not attach it to any poller.
	PollerFd (Poller &poller, int fd, EventInterests events, FdCallback cb)
	Takes ownership of `fd` and registers it to `poller`.
	PollerFd (Poller &poller, Utils::OwnedFd fd, EventInterests events, FdCallback cb)
	Takes ownership of `fd` and registers it to `poller`.
	PollerFd (PollerFd &&other) noexcept
	Move constructor.
	DFX_DISABLE_COPY (PollerFd)
	Copying is disabled because this type owns the FD.
	~PollerFd ()
	Destructor.
PollerFd &	operator= (PollerFd &&other) noexcept
	Move assignment.
bool	operator== (PollerFd const &) const noexcept=delete
bool	operator!= (PollerFd const &) const noexcept=delete
bool	operator== (int fd) const noexcept
bool	operator== (Utils::BorrowedFd const &fd) const noexcept
void	swap (PollerFd &other) noexcept
Utils::BorrowedFd	borrow () const noexcept
	Returns a non-owning view of the underlying FD.
Poller *	poller () const noexcept
	Returns the poller this FD is currently associated with (if any).
bool	isRegistered () const noexcept
	Returns whether this FD is currently registered in a poller.
int	get () const noexcept
	Returns the raw integer FD owned by this object.
bool	hasValidFd () const noexcept
	Returns true if the internal fd is valid.
void	attach (Poller &poller, Utils::OwnedFd fd, EventInterests events, FdCallback cb)
	Attaches this object to `poller` and adopts `fd`, registering it.
void	registerTo (Poller &poller, EventInterests events, FdCallback cb)
	Registers the currently owned FD into `poller`.
void	migrateTo (Poller &poller, EventInterests events, FdCallback cb)
	Moves the registration from the current poller to `poller`.
void	updateEvents (EventInterests events)
	Update the list of event that this fd is attached to.
void	deregister () noexcept
	Deregisters this FD from its poller (if registered).
void	reset () noexcept
	Fully releases resources: deregisters (if needed), drops poller association, and closes/releases the owned FD.

Detailed Description

RAII wrapper for the registration of a FD in a Poller.

PollerFd owns a file descriptor (via dfx::Utils::OwnedFd) and can register/deregister it into a Poller along with a callback and event interests.

This type is move-only: copying is disabled because it owns the underlying file descriptor and represents a single registration lifetime.

Typical usage:

Store it as default constructed member of a class
Call attach() to take ownership and register in the poller
Either let it be until destruction or explicitly reset() it

Note: poller() may be null when default-constructed, moved-from, or after reset().

Constructor & Destructor Documentation

◆ PollerFd() [1/5]

dfx::FdWatch::PollerFd::PollerFd ( )

defaultnoexcept

Constructs an empty handle with no poller association and no FD.

The instance is not registered and poller() returns null.

◆ PollerFd() [2/5]

dfx::FdWatch::PollerFd::PollerFd ( Utils::OwnedFd fd )

explicitnoexcept

Takes ownership of fd but do not attach it to any poller.

Parameters

fd	Owned file descriptor.

See also: registerTo

◆ PollerFd() [3/5]

dfx::FdWatch::PollerFd::PollerFd	(	Poller &	poller,
		int	fd,
		EventInterests	events,
		FdCallback	cb )

Takes ownership of fd and registers it to poller.

Parameters

poller	Poller in which the FD should be registered.
fd	Raw file descriptor to adopt.
events	Events of interest (e.g. readable/writable).
cb	Callback invoked by the poller when events occur.

Note: The provided integer FD is adopted (owned) by this object.

◆ PollerFd() [4/5]

dfx::FdWatch::PollerFd::PollerFd	(	Poller &	poller,
		Utils::OwnedFd	fd,
		EventInterests	events,
		FdCallback	cb )

Takes ownership of fd and registers it to poller.

Parameters

poller	Poller in which the FD should be registered.
fd	Owned file descriptor.
events	Events of interest (e.g. readable/writable).
cb	Callback invoked by the poller when events occur.

◆ PollerFd() [5/5]

dfx::FdWatch::PollerFd::PollerFd ( PollerFd && other )

noexcept

Move constructor.

Transfers FD ownership and any poller association/registration state. The moved-from object becomes empty/unregistered.

◆ ~PollerFd()

dfx::FdWatch::PollerFd::~PollerFd ( )

Destructor.

Releases the owned FD. If the instance is registered, it will be deregistered as part of cleanup and the FD will be subsequently closed

Member Function Documentation

◆ attach()

void dfx::FdWatch::PollerFd::attach	(	Poller &	poller,
		Utils::OwnedFd	fd,
		EventInterests	events,
		FdCallback	cb )

Attaches this object to poller and adopts fd, registering it.

This is typically used to initialize a default-constructed instance, or to reinitialize an existing instance after reset().

Parameters

poller	Poller in which the FD should be registered.
fd	Owned file descriptor to adopt.
events	Events of interest.
cb	Callback invoked when events occur.

◆ borrow()

Utils::BorrowedFd dfx::FdWatch::PollerFd::borrow ( ) const

inlinenodiscardnoexcept

Returns a non-owning view of the underlying FD.

Useful for APIs that require a dfx::Utils::BorrowedFd without transferring ownership.

Returns: A dfx::Utils::BorrowedFd referring to this instance.

◆ deregister()

void dfx::FdWatch::PollerFd::deregister ( )

noexcept

Deregisters this FD from its poller (if registered).

Keeps ownership of the FD (i.e. do not close it) but clears the registration state.

◆ DFX_DISABLE_COPY()

dfx::FdWatch::PollerFd::DFX_DISABLE_COPY ( PollerFd )

Copying is disabled because this type owns the FD.

◆ get()

int dfx::FdWatch::PollerFd::get ( ) const

inlinenoexcept

Returns the raw integer FD owned by this object.

Returns: The owned FD value, or an invalid value depending on dfx::Utils::OwnedFd semantics.

◆ hasValidFd()

bool dfx::FdWatch::PollerFd::hasValidFd ( ) const

inlinenoexcept

Returns true if the internal fd is valid.

The internal fd may be valid but not registered.

See also: isRegistered

◆ isRegistered()

bool dfx::FdWatch::PollerFd::isRegistered ( ) const

inlinenoexcept

Returns whether this FD is currently registered in a poller.

◆ migrateTo()

void dfx::FdWatch::PollerFd::migrateTo	(	Poller &	poller,
		EventInterests	events,
		FdCallback	cb )

Moves the registration from the current poller to poller.

Intended for cases where the FD must keep being watched but the poller instance changes (e.g. moving an object between reactors/threads).

Parameters

poller	Destination poller.
events	New events of interest.
cb	Callback invoked when events occur.

◆ operator=()

PollerFd & dfx::FdWatch::PollerFd::operator= ( PollerFd && other )

noexcept

Move assignment.

Releases current resources (if any), then transfers ownership/registration state from other.

◆ poller()

Poller * dfx::FdWatch::PollerFd::poller ( ) const

inlinenoexcept

Returns the poller this FD is currently associated with (if any).

Returns: Pointer to the poller, or null if not attached/registered.

◆ registerTo()

void dfx::FdWatch::PollerFd::registerTo	(	Poller &	poller,
		EventInterests	events,
		FdCallback	cb )

Registers the currently owned FD into poller.

Unlike attach(), this does not adopt a new FD; it uses the one already owned. And unlike migrateTo(), the FD must not already be registered to a poller.

Parameters

poller	Poller in which the FD should be registered.
events	Events of interest.
cb	Callback invoked when events occur.

◆ reset()

void dfx::FdWatch::PollerFd::reset ( )

noexcept

Fully releases resources: deregisters (if needed), drops poller association, and closes/releases the owned FD.

After reset(), the instance behaves like a default-constructed PollerFd.

◆ updateEvents()

void dfx::FdWatch::PollerFd::updateEvents ( EventInterests events )

Update the list of event that this fd is attached to.

Note that the callback is not touched by this call and will be called if any of the new events is triggered.

Parameters

events The new list of event to listen for.

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

lib/dfx-fdwatch/PollerFd.hpp

Public Member Functions

Detailed Description

Constructor & Destructor Documentation

◆ PollerFd() [1/5]

◆ PollerFd() [2/5]

◆ PollerFd() [3/5]

◆ PollerFd() [4/5]

◆ PollerFd() [5/5]

◆ ~PollerFd()

Member Function Documentation

◆ attach()

◆ borrow()

◆ deregister()

◆ DFX_DISABLE_COPY()

◆ get()

◆ hasValidFd()

◆ isRegistered()

◆ migrateTo()

◆ operator=()

◆ poller()

◆ registerTo()

◆ reset()

◆ updateEvents()