Wait Set Index Too Big

[gkuppa24]

Bug report

Required Info:

• Operating System:
  • Ubuntu 22.04
• Installation type:
  • binaries
• Version or commit hash: Humble
• DDS implementation: cyclone_dds
• Client library (if applicable): rclpy

Steps to reproduce issue

Traceback (most recent call last):
  File "/home/gauravkuppa24/.cache/bazel/_bazel_gauravkuppa24/0f5b194a5c00fda748ae81b2326da879/execroot/baserepo4/bazel-out/k8-fastbuild/bin/robot/task/task_manager/launch_high_level_planner/launch_high_level_planner.runfiles/baserepo4/robot/hardware/easo/lib/single_arm_node.py", line 659, in request_collision_cuboid_update
    self.executor.spin_until_future_complete(self.future,
  File "/home/gauravkuppa24/.cache/bazel/_bazel_gauravkuppa24/0f5b194a5c00fda748ae81b2326da879/execroot/baserepo4/bazel-out/k8-fastbuild/bin/robot/task/task_manager/launch_high_level_planner/launch_high_level_planner.runfiles/baserepo4/external/ros2_rclpy/rclpy/rclpy/executors.py", line 310, in spin_until_future_complete
    self.spin_once_until_future_complete(future, timeout_left)
  File "/home/gauravkuppa24/.cache/bazel/_bazel_gauravkuppa24/0f5b194a5c00fda748ae81b2326da879/execroot/baserepo4/bazel-out/k8-fastbuild/bin/robot/task/task_manager/launch_high_level_planner/launch_high_level_planner.runfiles/baserepo4/external/ros2_rclpy/rclpy/rclpy/executors.py", line 801, in spin_once_until_future_complete
    self._spin_once_impl(timeout_sec, future.done)
  File "/home/gauravkuppa24/.cache/bazel/_bazel_gauravkuppa24/0f5b194a5c00fda748ae81b2326da879/execroot/baserepo4/bazel-out/k8-fastbuild/bin/robot/task/task_manager/launch_high_level_planner/launch_high_level_planner.runfiles/baserepo4/external/ros2_rclpy/rclpy/rclpy/executors.py", line 775, in _spin_once_impl
    handler, entity, node = self.wait_for_ready_callbacks(
  File "/home/gauravkuppa24/.cache/bazel/_bazel_gauravkuppa24/0f5b194a5c00fda748ae81b2326da879/execroot/baserepo4/bazel-out/k8-fastbuild/bin/robot/task/task_manager/launch_high_level_planner/launch_high_level_planner.runfiles/baserepo4/external/ros2_rclpy/rclpy/rclpy/executors.py", line 711, in wait_for_ready_callbacks
    return next(self._cb_iter)
  File "/home/gauravkuppa24/.cache/bazel/_bazel_gauravkuppa24/0f5b194a5c00fda748ae81b2326da879/execroot/baserepo4/bazel-out/k8-fastbuild/bin/robot/task/task_manager/launch_high_level_planner/launch_high_level_planner.runfiles/baserepo4/external/ros2_rclpy/rclpy/rclpy/executors.py", line 630, in _wait_for_ready_callbacks
    if wt in waitables and wt.is_ready(wait_set):
  File "/home/gauravkuppa24/.cache/bazel/_bazel_gauravkuppa24/0f5b194a5c00fda748ae81b2326da879/execroot/baserepo4/bazel-out/k8-fastbuild/bin/robot/task/task_manager/launch_high_level_planner/launch_high_level_planner.runfiles/ros2_rclpy/rclpy/rclpy/qos_event.py", line 90, in is_ready
    if wait_set.is_ready('event', self._event_index):
IndexError: wait set index too big

Expected behavior

Actual behavior

Additional information

I cannot provide the code I am using to allow you to reproduce this bug, but it is a rclpy process that has a single MultiThreadedExecutor. The executor spins three nodes, and always gets hung up on this self.executor.spin_until_future_complete(self.future) with a wait set index bug.

Any advice on how to approach this problem would be much appreciated.

---

Feature request

Feature description

Implementation considerations

[Barry-Xu-2018]

Could you try using FastDDS (instead of cyclone_dds) to check if the problem still occurs in your environment ?

[gkuppa24]

Sure. I can give this a shot. Would service call would cause a QoS event added to the wait set? This seems to be the source of the bug.

[gkuppa24]

Neither cyclone_dds or fastrtps_cpp works.

[Barry-Xu-2018]

Sure. I can give this a shot. Would service call would cause a QoS event added to the wait set? This seems to be the source of the bug.

While creating publisher and subscription, you can set event_callbacks.

BTW, how did you determine it's related to the QoS Event?
Did you confirm the content of entity_type is "event" when "index >= num_entities" occurs?

rclpy/rclpy/src/rclpy/wait_set.cpp

Lines 157 to 197 in b488272

	bool
	WaitSet::is_ready(const std::string & entity_type, size_t index)
	{
	const void ** entities = NULL;
	size_t num_entities = 0;
	if ("subscription" == entity_type) {
	entities = reinterpret_cast<const void **>(rcl_wait_set_->subscriptions);
	num_entities = rcl_wait_set_->size_of_subscriptions;
	} else if ("client" == entity_type) {
	entities = reinterpret_cast<const void **>(rcl_wait_set_->clients);
	num_entities = rcl_wait_set_->size_of_clients;
	} else if ("service" == entity_type) {
	entities = reinterpret_cast<const void **>(rcl_wait_set_->services);
	num_entities = rcl_wait_set_->size_of_services;
	} else if ("timer" == entity_type) {
	entities = reinterpret_cast<const void **>(rcl_wait_set_->timers);
	num_entities = rcl_wait_set_->size_of_timers;
	} else if ("guard_condition" == entity_type) {
	entities = reinterpret_cast<const void **>(rcl_wait_set_->guard_conditions);
	num_entities = rcl_wait_set_->size_of_guard_conditions;
	} else if ("event" == entity_type) {
	entities = reinterpret_cast<const void **>(rcl_wait_set_->events);
	num_entities = rcl_wait_set_->size_of_events;
	} else {
	std::string error_text{"'"};
	error_text += entity_type;
	error_text += "' is not a known entity";
	throw std::runtime_error(error_text);
	}
	if (!entities) {
	std::string error_text{"wait set '"};
	error_text += entity_type;
	error_text += "' isn't allocated";
	throw std::runtime_error(error_text);
	}
	if (index >= num_entities) {
	throw std::out_of_range("wait set index too big");
	}
	return nullptr != entities[index];
	}