Inheritance diagram for rclcpp::TimerBase:

Public Member Functions
RCLCPP_PUBLIC	TimerBase (Clock::SharedPtr clock, std::chrono::nanoseconds period, rclcpp::Context::SharedPtr context, bool autostart=true)
	TimerBase constructor. More...

virtual RCLCPP_PUBLIC	~TimerBase ()
	TimerBase destructor.

RCLCPP_PUBLIC void	cancel ()
	Cancel the timer. More...

RCLCPP_PUBLIC bool	is_canceled ()
	Return the timer cancellation state. More...

RCLCPP_PUBLIC void	reset ()
	Reset the timer. More...

virtual RCLCPP_PUBLIC std::shared_ptr< void >	call ()=0
	Indicate that we're about to execute the callback. More...

virtual RCLCPP_PUBLIC void	execute_callback (const std::shared_ptr< void > &data)=0
	Call the callback function when the timer signal is emitted. More...

RCLCPP_PUBLIC std::shared_ptr< const rcl_timer_t >	get_timer_handle ()

RCLCPP_PUBLIC std::chrono::nanoseconds	time_until_trigger ()
	Check how long the timer has until its next scheduled callback. More...

virtual bool	is_steady ()=0
	Is the clock steady (i.e. is the time between ticks constant?) More...

RCLCPP_PUBLIC bool	is_ready ()
	Check if the timer is ready to trigger the callback. More...

RCLCPP_PUBLIC bool	exchange_in_use_by_wait_set_state (bool in_use_state)
	Exchange the "in use by wait set" state for this timer. More...

RCLCPP_PUBLIC void	set_on_reset_callback (std::function< void(size_t)> callback)
	Set a callback to be called when the timer is reset. More...

RCLCPP_PUBLIC void	clear_on_reset_callback ()
	Unset the callback registered for reset timer.

Protected Member Functions
RCLCPP_PUBLIC void	set_on_reset_callback (rcl_event_callback_t callback, const void *user_data)

Protected Attributes
std::recursive_mutex	callback_mutex_

std::function< void(size_t)>	on_reset_callback_ {nullptr}

Clock::SharedPtr	clock_

std::shared_ptr< rcl_timer_t >	timer_handle_

std::atomic< bool >	in_use_by_wait_set_ {false}

Detailed Description

Definition at line 53 of file timer.hpp.

Constructor & Destructor Documentation

◆ TimerBase()

TimerBase::TimerBase	(	Clock::SharedPtr	clock,
		std::chrono::nanoseconds	period,
		rclcpp::Context::SharedPtr	context,
		bool	autostart = `true`
	)

explicit

TimerBase constructor.

Parameters

clock	A clock to use for time and sleeping
period	The interval at which the timer fires
context	node context
autostart	timer state on initialization

In order to activate a timer that is not started on initialization, user should call the reset() method.

Definition at line 32 of file timer.cpp.

References rcl_get_default_allocator, rcl_get_zero_initialized_timer(), RCL_RET_OK, rcl_timer_fini(), and rcl_timer_init2().

Here is the call graph for this function:

Member Function Documentation

◆ call()

virtual RCLCPP_PUBLIC std::shared_ptr<void> rclcpp::TimerBase::call ( )

pure virtual

Indicate that we're about to execute the callback.

The multithreaded executor takes advantage of this to avoid scheduling the callback multiple times.

Returns: a valid shared_ptr if the callback should be executed, an invalid shared_ptr (nullptr) if the timer was canceled.

Implemented in rclcpp::GenericTimer< FunctorT, >.

◆ cancel()

void TimerBase::cancel ( )

Cancel the timer.

Exceptions

std::runtime_error if the rcl_timer_cancel returns a failure

Definition at line 83 of file timer.cpp.

References RCL_RET_OK, and rcl_timer_cancel().

Referenced by rclcpp::GenericTimer< FunctorT, >::~GenericTimer().

Here is the call graph for this function:

Here is the caller graph for this function:

◆ exchange_in_use_by_wait_set_state()

bool TimerBase::exchange_in_use_by_wait_set_state ( bool in_use_state )

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

This is used to ensure this timer 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.

Definition at line 147 of file timer.cpp.

◆ execute_callback()

virtual RCLCPP_PUBLIC void rclcpp::TimerBase::execute_callback ( const std::shared_ptr< void > & data )

pure virtual

Call the callback function when the timer signal is emitted.

Parameters

[in] data the pointer returned by the call function

Implemented in rclcpp::GenericTimer< FunctorT, >.

◆ is_canceled()

bool TimerBase::is_canceled ( )

Return the timer cancellation state.

Returns: true if the timer has been cancelled, false otherwise

Exceptions

std::runtime_error	if the rcl_get_error_state returns 0
rclcpp::exceptions::RCLError	some child class exception based on ret

Definition at line 92 of file timer.cpp.

References RCL_RET_OK, and rcl_timer_is_canceled().

Here is the call graph for this function:

◆ is_ready()

bool TimerBase::is_ready ( )

Check if the timer is ready to trigger the callback.

This function expects its caller to immediately trigger the callback after this function, since it maintains the last time the callback was triggered.

Returns: True if the timer needs to trigger.

Exceptions

std::runtime_error if it failed to check timer

Definition at line 116 of file timer.cpp.

References RCL_RET_OK, and rcl_timer_is_ready().

Here is the call graph for this function:

◆ is_steady()

virtual bool rclcpp::TimerBase::is_steady ( )

pure virtual

Is the clock steady (i.e. is the time between ticks constant?)

Returns: True if the clock used by this timer is steady.

Implemented in rclcpp::GenericTimer< FunctorT, >.

◆ reset()

void TimerBase::reset ( )

Reset the timer.

Exceptions

std::runtime_error if the rcl_timer_reset returns a failure

Definition at line 103 of file timer.cpp.

References RCL_RET_OK, and rcl_timer_reset().

Here is the call graph for this function:

◆ set_on_reset_callback()

void TimerBase::set_on_reset_callback ( std::function< void(size_t)> callback )

Set a callback to be called when the timer is reset.

You should aim to make this callback fast and not blocking. If you need to do a lot of work or wait for some other event, you should spin it off to another thread.

Calling it again will override any previously set callback. An exception will be thrown if the callback is not callable.

This function is thread-safe.

If you want more information available in the callback, you may use a lambda with captures or std::bind.

Parameters

[in] callback functor to be called whenever timer is reset

Definition at line 153 of file timer.cpp.

References rclcpp::get_logger(), and set_on_reset_callback().

Referenced by clear_on_reset_callback(), and set_on_reset_callback().

Here is the call graph for this function:

Here is the caller graph for this function:

◆ time_until_trigger()

std::chrono::nanoseconds TimerBase::time_until_trigger ( )

Check how long the timer has until its next scheduled callback.

Returns: A std::chrono::duration representing the relative time until the next callback or std::chrono::nanoseconds::max() if the timer is canceled.

Exceptions

std::runtime_error if the rcl_timer_get_time_until_next_call returns a failure

Definition at line 127 of file timer.cpp.

References RCL_RET_OK, RCL_RET_TIMER_CANCELED, and rcl_timer_get_time_until_next_call().

Here is the call graph for this function:

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

rclcpp/include/rclcpp/timer.hpp
rclcpp/src/rclcpp/timer.cpp

Public Member Functions

Protected Member Functions

Protected Attributes

Detailed Description

Constructor & Destructor Documentation

◆ TimerBase()

Member Function Documentation

◆ call()

◆ cancel()

◆ exchange_in_use_by_wait_set_state()

◆ execute_callback()

◆ is_canceled()

◆ is_ready()

◆ is_steady()

◆ reset()

◆ set_on_reset_callback()

◆ time_until_trigger()