rclcpp::GuardCondition Class Reference

A condition that can be waited on in a single wait set and asynchronously triggered. More...

#include <guard_condition.hpp>

Collaboration diagram for rclcpp::GuardCondition:

Public Member Functions
	GuardCondition (rclcpp::Context::SharedPtr context=rclcpp::contexts::get_global_default_context())
	Construct the guard condition, optionally specifying which Context to use. More...
virtual	~GuardCondition ()
rclcpp::Context::SharedPtr	get_context () const
	Return the context used when creating this guard condition. More...
const rcl_guard_condition_t &	get_rcl_guard_condition () const
	Return the underlying rcl guard condition structure. More...
void	trigger ()
	Notify the wait set waiting on this condition, if any, that the condition had been met. More...
bool	exchange_in_use_by_wait_set_state (bool in_use_state)
	Exchange the "in use by wait set" state for this guard condition. More...

Protected Attributes
rclcpp::Context::SharedPtr	context_
rcl_guard_condition_t	rcl_guard_condition_
std::atomic< bool >	in_use_by_wait_set_ {false}

Detailed Description

A condition that can be waited on in a single wait set and asynchronously triggered.

Constructor & Destructor Documentation

GuardCondition()

rclcpp::GuardCondition::GuardCondition ( rclcpp::Context::SharedPtr  context = rclcpp::contexts::get_global_default_context() )

explicit

Construct the guard condition, optionally specifying which Context to use.

Parameters

[in]

context

Optional custom context to be used. Defaults to using the global default context singleton. Shared ownership of the context is held with the guard condition until destruction.

Exceptions

std::invalid_argument	if the context is nullptr.
rclcpp::exceptions::RCLError	based exceptions when underlying rcl functions fail.

~GuardCondition()

virtual rclcpp::GuardCondition::~GuardCondition ( )

virtual

Member Function Documentation

get_context()

rclcpp::Context::SharedPtr rclcpp::GuardCondition::get_context

(

)

const

Return the context used when creating this guard condition.

get_rcl_guard_condition()

const rcl_guard_condition_t& rclcpp::GuardCondition::get_rcl_guard_condition

(

)

const

Return the underlying rcl guard condition structure.

trigger()

void rclcpp::GuardCondition::trigger

(

)

Notify the wait set waiting on this condition, if any, that the condition had been met.

This function is thread-safe, and may be called concurrently with waiting on this guard condition in a wait set.

Exceptions

rclcpp::exceptions::RCLError

based exceptions when underlying rcl functions fail.

exchange_in_use_by_wait_set_state()

bool rclcpp::GuardCondition::exchange_in_use_by_wait_set_state

(

bool

in_use_state

)

Exchange the "in use by wait set" state for this guard condition.

This is used to ensure this guard condition is not used by multiple wait sets at the same time.

Parameters

[in]

in_use_state

the new state to exchange into the state, true indicates it is now in use by a wait set, and false is that it is no longer in use by a wait set.

Returns

the previous state.

Member Data Documentation

context_

rclcpp::Context::SharedPtr rclcpp::GuardCondition::context_

protected

rcl_guard_condition_

rcl_guard_condition_t rclcpp::GuardCondition::rcl_guard_condition_

protected

in_use_by_wait_set_

std::atomic<bool> rclcpp::GuardCondition::in_use_by_wait_set_ {false}

protected

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

• include/rclcpp/guard_condition.hpp