rclcpp::executor::Executor Class Reference

Coordinate the order and timing of available communication tasks. More...

#include <executor.hpp>

Inheritance diagram for rclcpp::executor::Executor:

Public Member Functions
	Executor (const ExecutorArgs &args=create_default_executor_arguments())
	Default constructor. More...
virtual	~Executor ()
	Default destructor. More...
virtual void	spin ()=0
	Do work periodically as it becomes available to us. Blocking call, may block indefinitely. More...
virtual void	add_node (rclcpp::node_interfaces::NodeBaseInterface::SharedPtr node_ptr, bool notify=true)
	Add a node to the executor. More...
virtual void	add_node (std::shared_ptr< rclcpp::node::Node > node_ptr, bool notify=true)
	Convenience function which takes Node and forwards NodeBaseInterface. More...
virtual void	remove_node (rclcpp::node_interfaces::NodeBaseInterface::SharedPtr node_ptr, bool notify=true)
	Remove a node from the executor. More...
virtual void	remove_node (std::shared_ptr< rclcpp::node::Node > node_ptr, bool notify=true)
	Convenience function which takes Node and forwards NodeBaseInterface. More...
template<typename T = std::milli>
void	spin_node_once (rclcpp::node_interfaces::NodeBaseInterface::SharedPtr node, std::chrono::duration< int64_t, T > timeout=std::chrono::duration< int64_t, T >(-1))
	Add a node to executor, execute the next available unit of work, and remove the node. More...
template<typename NodeT = rclcpp::node::Node, typename T = std::milli>
void	spin_node_once (std::shared_ptr< NodeT > node, std::chrono::duration< int64_t, T > timeout=std::chrono::duration< int64_t, T >(-1))
	Convenience function which takes Node and forwards NodeBaseInterface. More...
void	spin_node_some (rclcpp::node_interfaces::NodeBaseInterface::SharedPtr node)
	Add a node, complete all immediately available work, and remove the node. More...
void	spin_node_some (std::shared_ptr< rclcpp::node::Node > node)
	Convenience function which takes Node and forwards NodeBaseInterface. More...
virtual void	spin_some ()
	Complete all available queued work without blocking. More...
virtual void	spin_once (std::chrono::nanoseconds timeout=std::chrono::nanoseconds(-1))
template<typename ResponseT , typename TimeT = std::milli>
FutureReturnCode	spin_until_future_complete (std::shared_future< ResponseT > &future, std::chrono::duration< int64_t, TimeT > timeout=std::chrono::duration< int64_t, TimeT >(-1))
	Spin (blocking) until the future is complete, it times out waiting, or rclcpp is interrupted. More...
void	cancel ()
	Cancel any running spin* function, causing it to return. More...
void	set_memory_strategy (memory_strategy::MemoryStrategy::SharedPtr memory_strategy)
	Support dynamic switching of the memory strategy. More...

Protected Member Functions
void	spin_node_once_nanoseconds (rclcpp::node_interfaces::NodeBaseInterface::SharedPtr node, std::chrono::nanoseconds timeout)
void	execute_any_executable (AnyExecutable::SharedPtr any_exec)
	Find the next available executable and do the work associated with it. More...
void	wait_for_work (std::chrono::nanoseconds timeout=std::chrono::nanoseconds(-1))
rclcpp::node_interfaces::NodeBaseInterface::SharedPtr	get_node_by_group (rclcpp::callback_group::CallbackGroup::SharedPtr group)
rclcpp::callback_group::CallbackGroup::SharedPtr	get_group_by_timer (rclcpp::timer::TimerBase::SharedPtr timer)
void	get_next_timer (AnyExecutable::SharedPtr any_exec)
AnyExecutable::SharedPtr	get_next_ready_executable ()
AnyExecutable::SharedPtr	get_next_executable (std::chrono::nanoseconds timeout=std::chrono::nanoseconds(-1))

Static Protected Member Functions
static void	execute_subscription (rclcpp::subscription::SubscriptionBase::SharedPtr subscription)
static void	execute_intra_process_subscription (rclcpp::subscription::SubscriptionBase::SharedPtr subscription)
static void	execute_timer (rclcpp::timer::TimerBase::SharedPtr timer)
static void	execute_service (rclcpp::service::ServiceBase::SharedPtr service)
static void	execute_client (rclcpp::client::ClientBase::SharedPtr client)

Protected Attributes
std::atomic_bool	spinning
	Spinning state, used to prevent multi threaded calls to spin and to cancel blocking spins. More...
rcl_guard_condition_t	interrupt_guard_condition_ = rcl_get_zero_initialized_guard_condition()
	Guard condition for signaling the rmw layer to wake up for special events. More...
rcl_wait_set_t	waitset_ = rcl_get_zero_initialized_wait_set()
	Waitset for managing entities that the rmw layer waits on. More...
memory_strategy::MemoryStrategy::SharedPtr	memory_strategy_
	The memory strategy: an interface for handling user-defined memory allocation strategies. More...

Detailed Description

Coordinate the order and timing of available communication tasks.

Executor provides spin functions (including spin_node_once and spin_some). It coordinates the nodes and callback groups by looking for available work and completing it, based on the threading or concurrency scheme provided by the subclass implementation. An example of available work is executing a subscription callback, or a timer callback. The executor structure allows for a decoupling of the communication graph and the execution model. See SingleThreadedExecutor and MultiThreadedExecutor for examples of execution paradigms.

Constructor & Destructor Documentation

Executor()

rclcpp::executor::Executor::Executor ( const ExecutorArgs &  args = create_default_executor_arguments() )

explicit

Default constructor.

~Executor()

virtual rclcpp::executor::Executor::~Executor ( )

virtual

Default destructor.

Member Function Documentation

spin()

virtual void rclcpp::executor::Executor::spin ( )

pure virtual

Do work periodically as it becomes available to us. Blocking call, may block indefinitely.

Implemented in rclcpp::executors::single_threaded_executor::SingleThreadedExecutor, and rclcpp::executors::multi_threaded_executor::MultiThreadedExecutor.

add_node() [1/2]

virtual void rclcpp::executor::Executor::add_node ( rclcpp::node_interfaces::NodeBaseInterface::SharedPtr  node_ptr, bool  notify = true  )

virtual

Add a node to the executor.

An executor can have zero or more nodes which provide work during spin functions.

Parameters

[in]	node_ptr	Shared pointer to the node to be added.
[in]	notify	True to trigger the interrupt guard condition during this function. If the executor is blocked at the rmw layer while waiting for work and it is notified that a new node was added, it will wake up.

add_node() [2/2]

virtual void rclcpp::executor::Executor::add_node ( std::shared_ptr< rclcpp::node::Node >  node_ptr, bool  notify = true  )

virtual

Convenience function which takes Node and forwards NodeBaseInterface.

remove_node() [1/2]

virtual void rclcpp::executor::Executor::remove_node ( rclcpp::node_interfaces::NodeBaseInterface::SharedPtr  node_ptr, bool  notify = true  )

virtual

Remove a node from the executor.

Parameters

[in]	node_ptr	Shared pointer to the node to remove.
[in]	notify	True to trigger the interrupt guard condition and wake up the executor. This is useful if the last node was removed from the executor while the executor was blocked waiting for work in another thread, because otherwise the executor would never be notified.

remove_node() [2/2]

virtual void rclcpp::executor::Executor::remove_node ( std::shared_ptr< rclcpp::node::Node >  node_ptr, bool  notify = true  )

virtual

Convenience function which takes Node and forwards NodeBaseInterface.

spin_node_once() [1/2]

template<typename T = std::milli>

void rclcpp::executor::Executor::spin_node_once ( rclcpp::node_interfaces::NodeBaseInterface::SharedPtr  node, std::chrono::duration< int64_t, T >  timeout = std::chrono::duration<int64_t, T>(-1)  )

inline

Add a node to executor, execute the next available unit of work, and remove the node.

Parameters

[in]	node	Shared pointer to the node to add.
[in]	timeout	How long to wait for work to become available. Negative values cause spin_node_once to block indefinitely (the default behavior). A timeout of 0 causes this function to be non-blocking.

spin_node_once() [2/2]

template<typename NodeT = rclcpp::node::Node, typename T = std::milli>

void rclcpp::executor::Executor::spin_node_once ( std::shared_ptr< NodeT >  node, std::chrono::duration< int64_t, T >  timeout = std::chrono::duration<int64_t, T>(-1)  )

inline

Convenience function which takes Node and forwards NodeBaseInterface.

spin_node_some() [1/2]

void rclcpp::executor::Executor::spin_node_some

(

rclcpp::node_interfaces::NodeBaseInterface::SharedPtr

node

)

Add a node, complete all immediately available work, and remove the node.

Parameters

[in]

node

Shared pointer to the node to add.

spin_node_some() [2/2]

void rclcpp::executor::Executor::spin_node_some

(

std::shared_ptr< rclcpp::node::Node >

node

)

Convenience function which takes Node and forwards NodeBaseInterface.

spin_some()

virtual void rclcpp::executor::Executor::spin_some ( )

virtual

Complete all available queued work without blocking.

This function can be overridden. The default implementation is suitable for a single-threaded model of execution. Adding subscriptions, timers, services, etc. with blocking callbacks will cause this function to block (which may have unintended consequences).

spin_once()

virtual void rclcpp::executor::Executor::spin_once ( std::chrono::nanoseconds  timeout = std::chrono::nanoseconds(-1) )

virtual

spin_until_future_complete()

template<typename ResponseT , typename TimeT = std::milli>

FutureReturnCode rclcpp::executor::Executor::spin_until_future_complete ( std::shared_future< ResponseT > &  future, std::chrono::duration< int64_t, TimeT >  timeout = std::chrono::duration<int64_t, TimeT>(-1)  )

inline

Spin (blocking) until the future is complete, it times out waiting, or rclcpp is interrupted.

Parameters

[in]	future	The future to wait on. If SUCCESS, the future is safe to access after this function.
[in]	timeout	Optional timeout parameter, which gets passed to Executor::spin_node_once. -1 is block forever, 0 is non-blocking. If the time spent inside the blocking loop exceeds this timeout, return a TIMEOUT return code.

Returns

The return code, one of SUCCESS, INTERRUPTED, or TIMEOUT.

cancel()

void rclcpp::executor::Executor::cancel

(

)

Cancel any running spin* function, causing it to return.

set_memory_strategy()

void rclcpp::executor::Executor::set_memory_strategy

(

memory_strategy::MemoryStrategy::SharedPtr

memory_strategy

)

Support dynamic switching of the memory strategy.

Switching the memory strategy while the executor is spinning in another threading could have unintended consequences.

Parameters

[in]

memory_strategy

Shared pointer to the memory strategy to set.

spin_node_once_nanoseconds()

void rclcpp::executor::Executor::spin_node_once_nanoseconds ( rclcpp::node_interfaces::NodeBaseInterface::SharedPtr  node, std::chrono::nanoseconds  timeout  )

protected

execute_any_executable()

void rclcpp::executor::Executor::execute_any_executable ( AnyExecutable::SharedPtr  any_exec )

protected

Find the next available executable and do the work associated with it.

Parameters

[in]

any_exec

Union structure that can hold any executable type (timer, subscription, service, client).

execute_subscription()

static void rclcpp::executor::Executor::execute_subscription ( rclcpp::subscription::SubscriptionBase::SharedPtr  subscription )

staticprotected

execute_intra_process_subscription()

static void rclcpp::executor::Executor::execute_intra_process_subscription ( rclcpp::subscription::SubscriptionBase::SharedPtr  subscription )

staticprotected

execute_timer()

static void rclcpp::executor::Executor::execute_timer ( rclcpp::timer::TimerBase::SharedPtr  timer )

staticprotected

execute_service()

static void rclcpp::executor::Executor::execute_service ( rclcpp::service::ServiceBase::SharedPtr  service )

staticprotected

execute_client()

static void rclcpp::executor::Executor::execute_client ( rclcpp::client::ClientBase::SharedPtr  client )

staticprotected

wait_for_work()

void rclcpp::executor::Executor::wait_for_work ( std::chrono::nanoseconds  timeout = std::chrono::nanoseconds(-1) )

protected

get_node_by_group()

rclcpp::node_interfaces::NodeBaseInterface::SharedPtr rclcpp::executor::Executor::get_node_by_group ( rclcpp::callback_group::CallbackGroup::SharedPtr  group )

protected

get_group_by_timer()

rclcpp::callback_group::CallbackGroup::SharedPtr rclcpp::executor::Executor::get_group_by_timer ( rclcpp::timer::TimerBase::SharedPtr  timer )

protected

get_next_timer()

void rclcpp::executor::Executor::get_next_timer ( AnyExecutable::SharedPtr  any_exec )

protected

get_next_ready_executable()

AnyExecutable::SharedPtr rclcpp::executor::Executor::get_next_ready_executable ( )

protected

get_next_executable()

AnyExecutable::SharedPtr rclcpp::executor::Executor::get_next_executable ( std::chrono::nanoseconds  timeout = std::chrono::nanoseconds(-1) )

protected

Member Data Documentation

spinning

std::atomic_bool rclcpp::executor::Executor::spinning

protected

Spinning state, used to prevent multi threaded calls to spin and to cancel blocking spins.

interrupt_guard_condition_

rcl_guard_condition_t rclcpp::executor::Executor::interrupt_guard_condition_ = rcl_get_zero_initialized_guard_condition()

protected

Guard condition for signaling the rmw layer to wake up for special events.

waitset_

rcl_wait_set_t rclcpp::executor::Executor::waitset_ = rcl_get_zero_initialized_wait_set()

protected

Waitset for managing entities that the rmw layer waits on.

memory_strategy_

memory_strategy::MemoryStrategy::SharedPtr rclcpp::executor::Executor::memory_strategy_

protected

The memory strategy: an interface for handling user-defined memory allocation strategies.

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

• include/rclcpp/executor.hpp