caf::actor_companion Class Reference

An co-existing actor forwarding all messages through a user-defined callback to another object, thus serving as gateway to allow any object to interact with other actors. More...

#include <actor_companion.hpp>

Inheritance diagram for caf::actor_companion:

Public Types
using	super = extended_base
using	signatures = none_t
	Required by spawn for type deduction.
using	behavior_type = behavior
	Required by spawn for type deduction.
using	enqueue_handler = std::function<void(mailbox_element_ptr)>
	Delegates incoming messages to user-defined event loop.
using	on_exit_handler = std::function<void()>
	Callback for actor termination.
Public Types inherited from caf::local_actor
using	clock_type = std::chrono::steady_clock
	Defines a monotonic clock suitable for measuring intervals.

Public Member Functions
bool	enqueue (mailbox_element_ptr ptr, scheduler *sched) override
	Enqueues a new message wrapped in a mailbox_element to the actor.
void	launch (scheduler *sched, bool lazy, bool hide) override
void	on_exit () override
	Can be overridden to perform cleanup code after an actor finished execution.
void	disconnect (exit_reason rsn=exit_reason::normal)
	Removes the handler for incoming messages and terminates the companion for exit reason rsn.
void	on_enqueue (enqueue_handler handler)
	Sets the handler for incoming messages.
void	on_exit (on_exit_handler handler)
	Sets the handler for incoming messages.
template<class... Args>
auto	mail (Args &&... args)
	Starts a new message.
template<class T , class... Ts>
void	become (T &&arg, Ts &&... args)
	Changes the behavior of this actor.
void	unbecome ()
	Removes the last added behavior.
Public Member Functions inherited from caf::local_actor
	local_actor (actor_config &cfg)
void	on_cleanup (const error &) override
	Called from cleanup to perform extra cleanup actions for this actor.
void	setup_metrics ()
clock_type::time_point	now () const noexcept
	Returns the current time.
disposable	request_response_timeout (timespan d, message_id mid)
	Requests a new timeout for mid.
template<class... Args>
void	println (std::string_view fmt, Args &&... args)
	Adds a new line to stdout.
template<class... Args>
void	println (term color, std::string_view fmt, Args &&... args)
	Adds a new line to stdout.
template<class T , spawn_options Os = no_spawn_options, class... Ts>
infer_handle_from_class_t< T >	spawn (Ts &&... xs)
template<spawn_options Options = no_spawn_options, class CustomSpawn , class... Args>
CustomSpawn::handle_type	spawn (CustomSpawn, Args &&... args)
template<spawn_options Os = no_spawn_options, class F , class... Ts>
infer_handle_from_fun_t< F >	spawn (F fun, Ts &&... xs)
void	send_exit (const actor_addr &receiver, error reason)
	Sends an exit message to receiver.
void	send_exit (const strong_actor_ptr &receiver, error reason)
	Sends an exit message to receiver.
template<class Handle >
void	send_exit (const Handle &receiver, error reason)
	Sends an exit message to receiver.
template<message_priority Priority = message_priority::normal, class Handle , class T , class... Ts>
void	anon_send (const Handle &receiver, T &&arg, Ts &&... args)
template<message_priority Priority = message_priority::normal, class Handle , class T , class... Ts>
disposable	scheduled_anon_send (const Handle &receiver, actor_clock::time_point timeout, T &&arg, Ts &&... args)
template<message_priority Priority = message_priority::normal, class Handle , class T , class... Ts>
disposable	delayed_anon_send (const Handle &receiver, actor_clock::duration_type timeout, T &&arg, Ts &&... args)
scheduler *	context () const noexcept
	Returns the execution unit currently used by this actor.
void	context (scheduler *x) noexcept
	Sets the execution unit for this actor.
actor_system &	system () const noexcept
	Returns the hosting actor system.
const actor_system_config &	config () const noexcept
	Returns the config of the hosting actor system.
actor_clock &	clock () const noexcept
	Returns the clock of the actor system.
strong_actor_ptr &	current_sender () noexcept
	Returns a pointer to the sender of the current message.
message_id	current_message_id () noexcept
	Returns the ID of the current message.
message_id	take_current_message_id () noexcept
	Returns the ID of the current message and marks the ID stored in the current mailbox element as answered.
void	drop_current_message_id () noexcept
	Marks the current message ID as answered.
mailbox_element *	current_mailbox_element () noexcept
	Returns a pointer to the currently processed mailbox element.
void	monitor (const node_id &node)
	Adds a unidirectional monitor to node.
void	demonitor (const node_id &node)
	Removes a monitor from node.
template<class... Ts>
detail::response_promise_t< Ts... >	make_response_promise ()
	Creates a typed_response_promise to respond to a request later on.
response_promise	make_response_promise ()
	Creates a response_promise to respond to a request later on.
const char *	name () const override
	Returns an implementation-dependent name for logging purposes, which is only valid as long as the actor is running.
virtual error	save_state (serializer &sink, unsigned int version)
	Serializes the state of this actor to sink.
virtual error	load_state (deserializer &source, unsigned int version)
	Deserializes the state of this actor from source.
const error &	fail_state () const noexcept
	Returns the currently defined fail state.
Public Member Functions inherited from caf::abstract_actor
	abstract_actor (const abstract_actor &)=delete
abstract_actor &	operator= (const abstract_actor &)=delete
void	attach (attachable_ptr ptr)
	Attaches ptr to this actor.
template<class F >
void	attach_functor (F f)
	Convenience function that attaches the functor f to this actor.
size_t	detach (const attachable::token &what)
	Detaches the first attached object that matches what.
void	link_to (const actor_addr &other)
	Links this actor to other.
template<class ActorHandle >
void	link_to (const ActorHandle &other)
	Links this actor to other.
void	unlink_from (const actor_addr &other)
	Unlinks this actor from addr.
template<class ActorHandle >
void	unlink_from (const ActorHandle &other)
	Links this actor to hdl.
virtual std::set< std::string >	message_types () const
	Returns the set of accepted messages types as strings or an empty set if this actor is untyped.
actor_id	id () const noexcept
	Returns the ID of this actor.
node_id	node () const noexcept
	Returns the node this actor is living on.
actor_system &	home_system () const noexcept
	Returns the system that created this actor (or proxy).
actor_control_block *	ctrl () const
	Returns the control block for this actor.
actor_addr	address () const noexcept
	Returns the logical actor address.
virtual mailbox_element *	peek_at_next_mailbox_element ()
	Called by the testing DSL to peek at the next element in the mailbox.
bool	cleanup (error &&reason, scheduler *sched)
	Called by the runtime system to perform cleanup actions for this actor.

Additional Inherited Members
Protected Member Functions inherited from caf::local_actor
void	do_send (abstract_actor *receiver, message_priority priority, message &&msg)
	Sends msg as an asynchronous message to receiver.
disposable	do_scheduled_send (strong_actor_ptr receiver, message_priority priority, actor_clock::time_point timeout, message &&msg)
	Sends msg as an asynchronous message to receiver after the timeout.
void	do_anon_send (abstract_actor *receiver, message_priority priority, message &&msg)
	Sends msg as an asynchronous message to receiver without sender information.
disposable	do_scheduled_anon_send (strong_actor_ptr receiver, message_priority priority, actor_clock::time_point timeout, message &&msg)
	Sends msg as an asynchronous message to receiver after the timeout without sender information.
void	do_monitor (abstract_actor *ptr, message_priority prio)
void	do_demonitor (const strong_actor_ptr &whom)
Protected Member Functions inherited from caf::abstract_actor
virtual void	on_unreachable ()
	Called on actor if the last strong reference to it expired without a prior call to quit(exit_reason::not_exited).
int	flags () const
void	flags (int new_value)
bool	is_terminated () const noexcept
	Checks whether this actor has terminated.
	abstract_actor (actor_config &cfg)
void	attach_impl (attachable_ptr &ptr)
size_t	detach_impl (const attachable::token &what, bool stop_on_hit=false, bool dry_run=false)
void	add_link (abstract_actor *other)
	Causes the actor to establish a link to other.
void	remove_link (abstract_actor *other)
	Causes the actor to remove any established link to other.
virtual bool	add_backlink (abstract_actor *other)
	Adds an entry to other to the link table of this actor.
virtual bool	remove_backlink (abstract_actor *other)
	Removes an entry to other from the link table of this actor.
Protected Attributes inherited from caf::local_actor
scheduler *	context_
mailbox_element *	current_element_
message_id	last_request_id_
detail::unique_function< behavior(local_actor *)>	initial_behavior_fac_
	Factory function for returning initial behavior in function-based actors.
metrics_t	metrics_
Protected Attributes inherited from caf::abstract_actor
std::atomic< int >	flags_
	Holds several state and type flags.
std::mutex	mtx_
	Guards members that may be subject to concurrent access .
std::condition_variable	cv_
	Allows blocking actors to actively wait for incoming messages.
error	fail_state_
	Stores the user-defined exit reason if this actor has finished execution.
attachable_ptr	attachables_head_
	Points to the first attachable in the linked list of attachables (if any).
Related Symbols inherited from caf::local_actor
constexpr keep_behavior_t	keep_behavior = keep_behavior_t{}
	Policy tag that causes event_based_actor::become to keep the current behavior available.
Related Symbols inherited from caf::abstract_actor
using	actor_id = uint64_t
	A unique actor ID.

Detailed Description

An co-existing actor forwarding all messages through a user-defined callback to another object, thus serving as gateway to allow any object to interact with other actors.

Member Function Documentation

become()

template<class T , class... Ts>

void caf::actor_companion::become	(	T &&	arg,
		Ts &&...	args )

Changes the behavior of this actor.

enqueue()

bool caf::actor_companion::enqueue ( mailbox_element_ptr what, scheduler * sched )

overridevirtual

Enqueues a new message wrapped in a mailbox_element to the actor.

This enqueue variant allows to define forwarding chains.

Returns

true if the message has added to the mailbox, false otherwise. In the latter case, the actor terminated and the message has been dropped. Once this function returns false, it returns false for all future invocations.

Note

The returned value is purely informational and may be used to discard actor handles early. Messages may still get dropped later even if this function returns true. In particular when dealing with remote actors.

Implements caf::abstract_actor.

launch()

void caf::actor_companion::launch ( scheduler * sched, bool lazy, bool hide )

overridevirtual

Implements caf::local_actor.

on_enqueue()

void caf::actor_companion::on_enqueue

(

enqueue_handler

handler

)

Sets the handler for incoming messages.

Warning

handler needs to be thread-safe

on_exit()

void caf::actor_companion::on_exit ( )

overridevirtual

Can be overridden to perform cleanup code after an actor finished execution.

Reimplemented from caf::local_actor.

unbecome()

void caf::actor_companion::unbecome

(

)

Removes the last added behavior.

Terminates the actor if there are no behaviors left.

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

• libcaf_core/caf/actor_companion.hpp
• libcaf_core/caf/actor_companion.cpp