rclcpp::graph_listener::GraphListener Class Reference

Notifies many nodes of graph changes by listening in a thread. More...

#include <rclcpp/graph_listener.hpp>

Inheritance diagram for rclcpp::graph_listener::GraphListener:

Collaboration diagram for rclcpp::graph_listener::GraphListener:

Public Member Functions
RCLCPP_PUBLIC	GraphListener (const rclcpp::Context::SharedPtr &parent_context)
virtual RCLCPP_PUBLIC void	start_if_not_started ()
	Start the graph listener's listen thread if it hasn't been started. More...
virtual RCLCPP_PUBLIC void	add_node (rclcpp::node_interfaces::NodeGraphInterface *node_graph)
	Add a node to the graph listener's list of nodes. More...
virtual RCLCPP_PUBLIC bool	has_node (rclcpp::node_interfaces::NodeGraphInterface *node_graph)
	Return true if the given node is in the graph listener's list of nodes. More...
virtual RCLCPP_PUBLIC void	remove_node (rclcpp::node_interfaces::NodeGraphInterface *node_graph)
	Remove a node from the graph listener's list of nodes. More...
virtual RCLCPP_PUBLIC void	shutdown ()
	Stop the listening thread. More...
virtual RCLCPP_PUBLIC void	shutdown (const std::nothrow_t &) noexcept
	Nothrow version of shutdown(), logs to RCLCPP_ERROR instead.
virtual RCLCPP_PUBLIC bool	is_shutdown ()
	Return true if shutdown() has been called, else false.

Protected Member Functions
virtual RCLCPP_PUBLIC void	run ()
	Main function for the listening thread.
virtual RCLCPP_PUBLIC void	run_loop ()
RCLCPP_PUBLIC void	init_wait_set ()
RCLCPP_PUBLIC void	cleanup_wait_set ()

Detailed Description

Notifies many nodes of graph changes by listening in a thread.

Definition at line 63 of file graph_listener.hpp.

Member Function Documentation

add_node()

void rclcpp::graph_listener::GraphListener::add_node ( rclcpp::node_interfaces::NodeGraphInterface *  node_graph )

virtual

Add a node to the graph listener's list of nodes.

Exceptions

GraphListenerShutdownError	if the GraphListener is shutdown
NodeAlreadyAddedError	if the given node is already in the list
std::invalid_argument	if node is nullptr
std::system_error	anything std::mutex::lock() throws

Definition at line 254 of file graph_listener.cpp.

has_node()

bool rclcpp::graph_listener::GraphListener::has_node ( rclcpp::node_interfaces::NodeGraphInterface *  node_graph )

virtual

Return true if the given node is in the graph listener's list of nodes.

Also return false if given nullptr.

Exceptions

std::system_error

anything std::mutex::lock() throws

Definition at line 237 of file graph_listener.cpp.

remove_node()

void rclcpp::graph_listener::GraphListener::remove_node ( rclcpp::node_interfaces::NodeGraphInterface *  node_graph )

virtual

Remove a node from the graph listener's list of nodes.

Exceptions

NodeNotFoundError	if the given node is not in the list
std::invalid_argument	if node is nullptr
std::system_error	anything std::mutex::lock() throws

Definition at line 299 of file graph_listener.cpp.

shutdown()

void rclcpp::graph_listener::GraphListener::shutdown ( )

virtual

Stop the listening thread.

The thread cannot be restarted, and the class is defunct after calling. This function is called by the ~GraphListener() and does nothing if shutdown() was already called. This function exists separately from the ~GraphListener() so that it can be called before and exceptions can be caught.

If start_if_not_started() was never called, this function still succeeds, but start_if_not_started() still cannot be called after this function.

Note that if you override this method, but leave shutdown to be called in the destruction of this base class, it will not call the overridden version from your base class. So you need to ensure you call your class's shutdown() in its destructor.

Exceptions

rclcpp::execptions::RCLError	from rcl_guard_condition_fini()
rclcpp::execptions::RCLError	from rcl_wait_set_fini()
std::system_error	anything std::mutex::lock() throws

Definition at line 346 of file graph_listener.cpp.

start_if_not_started()

void rclcpp::graph_listener::GraphListener::start_if_not_started ( )

virtual

Start the graph listener's listen thread if it hasn't been started.

This function is thread-safe.

Exceptions

GraphListenerShutdownError	if the GraphListener is shutdown
std::runtime	if the parent context was destroyed
anything	rclcpp::exceptions::throw_from_rcl_error can throw.

Definition at line 72 of file graph_listener.cpp.

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

• rclcpp/include/rclcpp/graph_listener.hpp
• rclcpp/src/rclcpp/graph_listener.cpp