#include <subscription_base.hpp>

Inheritance diagram for rclcpp::SubscriptionBase:

Collaboration diagram for rclcpp::SubscriptionBase:

[legend]

Public Types
using	IntraProcessManagerWeakPtr = std::weak_ptr< rclcpp::experimental::IntraProcessManager >

Public Member Functions
	SubscriptionBase (rclcpp::node_interfaces::NodeBaseInterface *node_base, const rosidl_message_type_support_t &type_support_handle, const std::string &topic_name, const rcl_subscription_options_t &subscription_options, bool is_serialized=false)
	Default constructor. More...

virtual	~SubscriptionBase ()
	Default destructor. More...

const char *	get_topic_name () const
	Get the topic that this subscription is subscribed on. More...

std::shared_ptr< rcl_subscription_t >	get_subscription_handle ()

std::shared_ptr< const rcl_subscription_t >	get_subscription_handle () const

const std::vector< std::shared_ptr< rclcpp::QOSEventHandlerBase > > &	get_event_handlers () const
	Get all the QoS event handlers associated with this subscription. More...

rclcpp::QoS	get_actual_qos () const
	Get the actual QoS settings, after the defaults have been determined. More...

bool	take_type_erased (void *message_out, rclcpp::MessageInfo &message_info_out)
	Take the next inter-process message from the subscription as a type erased pointer. More...

bool	take_serialized (rclcpp::SerializedMessage &message_out, rclcpp::MessageInfo &message_info_out)
	Take the next inter-process message, in its serialized form, from the subscription. More...

virtual std::shared_ptr< void >	create_message ()=0
	Borrow a new message. More...

virtual std::shared_ptr< rclcpp::SerializedMessage >	create_serialized_message ()=0
	Borrow a new serialized message. More...

virtual void	handle_message (std::shared_ptr< void > &message, const rclcpp::MessageInfo &message_info)=0
	Check if we need to handle the message, and execute the callback if we do. More...

virtual void	handle_loaned_message (void *loaned_message, const rclcpp::MessageInfo &message_info)=0

virtual void	return_message (std::shared_ptr< void > &message)=0
	Return the message borrowed in create_message. More...

virtual void	return_serialized_message (std::shared_ptr< rclcpp::SerializedMessage > &message)=0
	Return the message borrowed in create_serialized_message. More...

const rosidl_message_type_support_t &	get_message_type_support_handle () const

bool	is_serialized () const
	Return if the subscription is serialized. More...

size_t	get_publisher_count () const
	Get matching publisher count. More...

bool	can_loan_messages () const
	Check if subscription instance can loan messages. More...

void	setup_intra_process (uint64_t intra_process_subscription_id, IntraProcessManagerWeakPtr weak_ipm)
	Implemenation detail. More...

rclcpp::Waitable::SharedPtr	get_intra_process_waitable () const
	Return the waitable for intra-process. More...

bool	exchange_in_use_by_wait_set_state (void *pointer_to_subscription_part, bool in_use_state)
	Exchange state of whether or not a part of the subscription is used by a wait set. More...

Public Member Functions inherited from std::enable_shared_from_this< SubscriptionBase >
T	enable_shared_from_this (T... args)

T	operator= (T... args)

T	shared_from_this (T... args)

T	~enable_shared_from_this (T... args)

Protected Member Functions
template<typename EventCallbackT >
void	add_event_handler (const EventCallbackT &callback, const rcl_subscription_event_type_t event_type)

void	default_incompatible_qos_callback (QOSRequestedIncompatibleQoSInfo &info) const

bool	matches_any_intra_process_publishers (const rmw_gid_t *sender_gid) const

Detailed Description

Virtual base class for subscriptions. This pattern allows us to iterate over different template specializations of Subscription, among other things.

Member Typedef Documentation

◆ IntraProcessManagerWeakPtr

using rclcpp::SubscriptionBase::IntraProcessManagerWeakPtr = std::weak_ptr<rclcpp::experimental::IntraProcessManager>

Constructor & Destructor Documentation

◆ SubscriptionBase()

rclcpp::SubscriptionBase::SubscriptionBase	(	rclcpp::node_interfaces::NodeBaseInterface *	node_base,
		const rosidl_message_type_support_t &	type_support_handle,
		const std::string &	topic_name,
		const rcl_subscription_options_t &	subscription_options,
		bool	is_serialized = `false`
	)

Default constructor.

Parameters

[in]	node_base	NodeBaseInterface pointer used in parts of the setup.
[in]	type_support_handle	rosidl type support struct, for the Message type of the topic.
[in]	topic_name	Name of the topic to subscribe to.
[in]	subscription_options	options for the subscription.
[in]	is_serialized	is true if the message will be delivered still serialized

◆ ~SubscriptionBase()

virtual rclcpp::SubscriptionBase::~SubscriptionBase ( )

virtual

Default destructor.

Member Function Documentation

◆ get_topic_name()

const char* rclcpp::SubscriptionBase::get_topic_name ( ) const

Get the topic that this subscription is subscribed on.

◆ get_subscription_handle() [1/2]

std::shared_ptr<rcl_subscription_t> rclcpp::SubscriptionBase::get_subscription_handle ( )

◆ get_subscription_handle() [2/2]

std::shared_ptr<const rcl_subscription_t> rclcpp::SubscriptionBase::get_subscription_handle ( ) const

◆ get_event_handlers()

const std::vector<std::shared_ptr<rclcpp::QOSEventHandlerBase> >& rclcpp::SubscriptionBase::get_event_handlers ( ) const

Get all the QoS event handlers associated with this subscription.

Returns: The vector of QoS event handlers.

◆ get_actual_qos()

rclcpp::QoS rclcpp::SubscriptionBase::get_actual_qos ( ) const

Get the actual QoS settings, after the defaults have been determined.

The actual configuration applied when using RMW_QOS_POLICY_*_SYSTEM_DEFAULT can only be resolved after the creation of the publisher, and it depends on the underlying rmw implementation. If the underlying setting in use can't be represented in ROS terms, it will be set to RMW_QOS_POLICY_*_UNKNOWN. May throw runtime_error when an unexpected error occurs.

Returns: The actual qos settings.

Exceptions

std::runtime_error if failed to get qos settings

◆ take_type_erased()

bool rclcpp::SubscriptionBase::take_type_erased	(	void *	message_out,
		rclcpp::MessageInfo &	message_info_out
	)

Take the next inter-process message from the subscription as a type erased pointer.

See also: Subscription::take() for details on how this function works.

The only difference is that it takes a type erased pointer rather than a reference to the exact message type.

This type erased version facilitates using the subscriptions in a type agnostic way using SubscriptionBase::create_message() and SubscriptionBase::handle_message().

Parameters

[out]	message_out	The type erased message pointer into which take will copy the data.
[out]	message_info_out	The message info for the taken message.

Returns: true if data was taken and is valid, otherwise false

Exceptions

any	rcl errors from rcl_take,

See also: rclcpp::exceptions::throw_from_rcl_error()

◆ take_serialized()

bool rclcpp::SubscriptionBase::take_serialized	(	rclcpp::SerializedMessage &	message_out,
		rclcpp::MessageInfo &	message_info_out
	)

Take the next inter-process message, in its serialized form, from the subscription.

For now, if data is taken (written) into the message_out and message_info_out then true will be returned. Unlike Subscription::take(), taking data serialized is not possible via intra-process for the time being, so it will not need to de-duplicate data in any case.

Parameters

[out]	message_out	The serialized message data structure used to store the taken message.
[out]	message_info_out	The message info for the taken message.

Returns: true if data was taken and is valid, otherwise false

Exceptions

any	rcl errors from rcl_take,

See also: rclcpp::exceptions::throw_from_rcl_error()

◆ create_message()

virtual std::shared_ptr<void> rclcpp::SubscriptionBase::create_message ( )

pure virtual

Borrow a new message.

Returns: Shared pointer to the fresh message.

Implemented in rclcpp::Subscription< CallbackMessageT, AllocatorT, MessageMemoryStrategyT >.

◆ create_serialized_message()

virtual std::shared_ptr<rclcpp::SerializedMessage> rclcpp::SubscriptionBase::create_serialized_message ( )

pure virtual

Borrow a new serialized message.

Returns: Shared pointer to a rcl_message_serialized_t.

Implemented in rclcpp::Subscription< CallbackMessageT, AllocatorT, MessageMemoryStrategyT >.

◆ handle_message()

virtual void rclcpp::SubscriptionBase::handle_message	(	std::shared_ptr< void > &	message,
		const rclcpp::MessageInfo &	message_info
	)

pure virtual

Check if we need to handle the message, and execute the callback if we do.

Parameters

[in]	message	Shared pointer to the message to handle.
[in]	message_info	Metadata associated with this message.

Implemented in rclcpp::Subscription< CallbackMessageT, AllocatorT, MessageMemoryStrategyT >.

◆ handle_loaned_message()

virtual void rclcpp::SubscriptionBase::handle_loaned_message	(	void *	loaned_message,
		const rclcpp::MessageInfo &	message_info
	)

pure virtual

Implemented in rclcpp::Subscription< CallbackMessageT, AllocatorT, MessageMemoryStrategyT >.

◆ return_message()

virtual void rclcpp::SubscriptionBase::return_message ( std::shared_ptr< void > & message )

pure virtual

Return the message borrowed in create_message.

Parameters

[in] message Shared pointer to the returned message.

Implemented in rclcpp::Subscription< CallbackMessageT, AllocatorT, MessageMemoryStrategyT >.

◆ return_serialized_message()

virtual void rclcpp::SubscriptionBase::return_serialized_message ( std::shared_ptr< rclcpp::SerializedMessage > & message )

pure virtual

Return the message borrowed in create_serialized_message.

Parameters

[in] message Shared pointer to the returned message.

Implemented in rclcpp::Subscription< CallbackMessageT, AllocatorT, MessageMemoryStrategyT >.

◆ get_message_type_support_handle()

const rosidl_message_type_support_t& rclcpp::SubscriptionBase::get_message_type_support_handle ( ) const

◆ is_serialized()

bool rclcpp::SubscriptionBase::is_serialized ( ) const

Return if the subscription is serialized.

Returns: true if the subscription is serialized, false otherwise

◆ get_publisher_count()

size_t rclcpp::SubscriptionBase::get_publisher_count ( ) const

Get matching publisher count.

Returns: The number of publishers on this topic.

◆ can_loan_messages()

bool rclcpp::SubscriptionBase::can_loan_messages ( ) const

Check if subscription instance can loan messages.

Depending on the middleware and the message type, this will return true if the middleware can allocate a ROS message instance.

Returns: boolean flag indicating if middleware can loan messages.

◆ setup_intra_process()

void rclcpp::SubscriptionBase::setup_intra_process	(	uint64_t	intra_process_subscription_id,
		IntraProcessManagerWeakPtr	weak_ipm
	)

Implemenation detail.

◆ get_intra_process_waitable()

rclcpp::Waitable::SharedPtr rclcpp::SubscriptionBase::get_intra_process_waitable ( ) const

Return the waitable for intra-process.

Returns: the waitable sharedpointer for intra-process, or nullptr if intra-process is not setup.

Exceptions

std::runtime_error if the intra process manager is destroyed

◆ exchange_in_use_by_wait_set_state()

bool rclcpp::SubscriptionBase::exchange_in_use_by_wait_set_state	(	void *	pointer_to_subscription_part,
		bool	in_use_state
	)

Exchange state of whether or not a part of the subscription is used by a wait set.

Used to ensure parts of the subscription are not used with multiple wait sets simultaneously.

Parameters

[in]	pointer_to_subscription_part	address of a subscription part
[in]	in_use_state	the new state to exchange, true means "now in use", and false means "no longer in use".

Returns: the current "in use" state.

Exceptions

std::invalid_argument	If pointer_to_subscription_part is nullptr.
std::runtime_error	If the pointer given is not a pointer to one of the parts of the subscription which can be used with a wait set.

◆ add_event_handler()

template<typename EventCallbackT >

void rclcpp::SubscriptionBase::add_event_handler	(	const EventCallbackT &	callback,
		const rcl_subscription_event_type_t	event_type
	)

inlineprotected

◆ default_incompatible_qos_callback()

void rclcpp::SubscriptionBase::default_incompatible_qos_callback ( QOSRequestedIncompatibleQoSInfo & info ) const

protected

◆ matches_any_intra_process_publishers()

bool rclcpp::SubscriptionBase::matches_any_intra_process_publishers ( const rmw_gid_t * sender_gid ) const

protected

Member Data Documentation

◆ node_base_

rclcpp::node_interfaces::NodeBaseInterface* const rclcpp::SubscriptionBase::node_base_

protected

◆ node_handle_

std::shared_ptr<rcl_node_t> rclcpp::SubscriptionBase::node_handle_

protected

◆ subscription_handle_

std::shared_ptr<rcl_subscription_t> rclcpp::SubscriptionBase::subscription_handle_

protected

◆ intra_process_subscription_handle_

std::shared_ptr<rcl_subscription_t> rclcpp::SubscriptionBase::intra_process_subscription_handle_

protected

◆ event_handlers_

std::vector<std::shared_ptr<rclcpp::QOSEventHandlerBase> > rclcpp::SubscriptionBase::event_handlers_

protected

◆ use_intra_process_

bool rclcpp::SubscriptionBase::use_intra_process_

protected

◆ weak_ipm_

IntraProcessManagerWeakPtr rclcpp::SubscriptionBase::weak_ipm_

protected

◆ intra_process_subscription_id_

uint64_t rclcpp::SubscriptionBase::intra_process_subscription_id_

protected

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

include/rclcpp/subscription_base.hpp

Protected Attributes
rclcpp::node_interfaces::NodeBaseInterface *const	node_base_

std::shared_ptr< rcl_node_t >	node_handle_

std::shared_ptr< rcl_subscription_t >	subscription_handle_

std::shared_ptr< rcl_subscription_t >	intra_process_subscription_handle_

std::vector< std::shared_ptr< rclcpp::QOSEventHandlerBase > >	event_handlers_

bool	use_intra_process_

IntraProcessManagerWeakPtr	weak_ipm_

uint64_t	intra_process_subscription_id_

Public Types

Public Member Functions

Protected Member Functions

Protected Attributes

Detailed Description

Member Typedef Documentation

◆ IntraProcessManagerWeakPtr

Constructor & Destructor Documentation

◆ SubscriptionBase()

◆ ~SubscriptionBase()

Member Function Documentation

◆ get_topic_name()

◆ get_subscription_handle() [1/2]

◆ get_subscription_handle() [2/2]

◆ get_event_handlers()

◆ get_actual_qos()

◆ take_type_erased()

◆ take_serialized()

◆ create_message()

◆ create_serialized_message()

◆ handle_message()

◆ handle_loaned_message()

◆ return_message()

◆ return_serialized_message()

◆ get_message_type_support_handle()

◆ is_serialized()

◆ get_publisher_count()

◆ can_loan_messages()

◆ setup_intra_process()

◆ get_intra_process_waitable()

◆ exchange_in_use_by_wait_set_state()

◆ add_event_handler()

◆ default_incompatible_qos_callback()

◆ matches_any_intra_process_publishers()

Member Data Documentation

◆ node_base_

◆ node_handle_

◆ subscription_handle_

◆ intra_process_subscription_handle_

◆ event_handlers_

◆ use_intra_process_

◆ weak_ipm_

◆ intra_process_subscription_id_