2.4.3

Signed-off-by: Dharini Dutia <dharini@openrobotics.org>

README.md

@@ -0,0 +1,17 @@
+# rclcpp
+
+This repository contains the source code for the ROS Client Library for C++ package, included with a standard install of any ROS 2 distro.
+
+rclcpp provides the standard C++ API for interacting with ROS 2.
+
+## Usage
+
+`#include "rclcpp/rclcpp.hpp"` allows use of the most common elements of the ROS 2 system.
+
+Visit the [rclcpp API documentation](http://docs.ros2.org/foxy/api/rclcpp/) for a complete list of its main components.
+
+### Examples
+
+The ROS 2 tutorials [Writing a simple publisher and subscriber](https://docs.ros.org/en/foxy/Tutorials/Writing-A-Simple-Cpp-Publisher-And-Subscriber.html).
+and [Writing a simple service and client](https://docs.ros.org/en/foxy/Tutorials/Writing-A-Simple-Cpp-Service-And-Client.html)
+contain some examples of rclcpp APIs in use.

rclcpp/CHANGELOG.rst

@@ -2,6 +2,292 @@
 Changelog for package rclcpp
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
+2.4.3 (2023-05-27)
+------------------
+* Do not attempt to use void allocators for memory allocation. (backport `#1657 <https://github.com/ros2/rclcpp/issues/1657>`_) (`#2004 <https://github.com/ros2/rclcpp/issues/2004>`_)
+* Contributors: Michel Hidalgo
+
+2.4.2 (2022-07-25)
+------------------
+* Add statistics for handle_loaned_message (`#1927 <https://github.com/ros2/rclcpp/issues/1927>`_) (`#1934 <https://github.com/ros2/rclcpp/issues/1934>`_)
+* Add test-dep ament_cmake_google_benchmark (`#1904 <https://github.com/ros2/rclcpp/issues/1904>`_) (`#1910 <https://github.com/ros2/rclcpp/issues/1910>`_)
+* Use parantheses around logging macro parameter (`#1820 <https://github.com/ros2/rclcpp/issues/1820>`_) (`#1823 <https://github.com/ros2/rclcpp/issues/1823>`_)
+* Contributors: Abrar Rahman Protyasha, Barry Xu, Gaël Écorchard
+
+2.4.1 (2022-01-31)
+------------------
+* Fix subscription instrumentation for ConstSharedPtr[WithInfo]Callback (`#1872 <https://github.com/ros2/rclcpp/issues/1872>`_)
+* Add node_waitables\_ to copy constructor (backport `#1799 <https://github.com/ros2/rclcpp/issues/1799>`_) (`#1834 <https://github.com/ros2/rclcpp/issues/1834>`_)
+* Fix returning invalid namespace if sub_namespace is empty (`#1658 <https://github.com/ros2/rclcpp/issues/1658>`_) (`#1811 <https://github.com/ros2/rclcpp/issues/1811>`_)
+* [service] Don't use a weak_ptr to avoid leaking (`#1668 <https://github.com/ros2/rclcpp/issues/1668>`_) (`#1669 <https://github.com/ros2/rclcpp/issues/1669>`_)
+* Use dynamic_pointer_cast to detect allocator mismatch in intra process manager (backport `#1643 <https://github.com/ros2/rclcpp/issues/1643>`_) (`#1645 <https://github.com/ros2/rclcpp/issues/1645>`_)
+* Contributors: Abrar Rahman Protyasha, Christophe Bedard, Ivan Santiago Paunovic, M. Hofstätter, Michel Hidalgo, Tomoya Fujita, William Woodall
+
+2.4.0 (2021-09-01)
+------------------
+* Guard against integer overflow in duration conversion (`#1584 <https://github.com/ros2/rclcpp/issues/1584>`_) (`#1761 <https://github.com/ros2/rclcpp/issues/1761>`_)
+* Update for checking correct variable (`#1534 <https://github.com/ros2/rclcpp/issues/1534>`_) (`#1760 <https://github.com/ros2/rclcpp/issues/1760>`_)
+* Fix SEGV caused by order of destruction of Node sub-interfaces (`#1469 <https://github.com/ros2/rclcpp/issues/1469>`_) (`#1736 <https://github.com/ros2/rclcpp/issues/1736>`_)
+* Add wait for message API (`#1705 <https://github.com/ros2/rclcpp/issues/1705>`_) (`#1737 <https://github.com/ros2/rclcpp/issues/1737>`_)
+* Fix documentation bug (`#1719 <https://github.com/ros2/rclcpp/issues/1719>`_) (`#1721 <https://github.com/ros2/rclcpp/issues/1721>`_)
+* Fix clock thread issue (`#1266 <https://github.com/ros2/rclcpp/issues/1266>`_) (`#1267 <https://github.com/ros2/rclcpp/issues/1267>`_) (`#1685 <https://github.com/ros2/rclcpp/issues/1685>`_)
+* Allow timers to keep up the intended rate in MultiThreadedExecutor `#1516 <https://github.com/ros2/rclcpp/issues/1516>`_ (`#1636 <https://github.com/ros2/rclcpp/issues/1636>`_)
+  Backports `#1516 <https://github.com/ros2/rclcpp/issues/1516>`_ and follow-up fix `#1628 <https://github.com/ros2/rclcpp/issues/1628>`_
+* Contributors: Chen Lihui, Colin MacKenzie, Daisuke Sato, Jacob Perron, Karsten Knese, Tomoya Fujita, hsgwa, William Woodall
+
+2.3.1 (2021-04-14)
+------------------
+* Update quality declaration links (re: `ros2/docs.ros2.org#52 <https://github.com/ros2/docs.ros2.org/issues/52>`_) (`#1616 <https://github.com/ros2/rclcpp/issues/1616>`_)
+* Fix documented example in create_publisher (`#1558 <https://github.com/ros2/rclcpp/issues/1558>`_) (`#1559 <https://github.com/ros2/rclcpp/issues/1559>`_)
+* Fix runtime error: reference binding to null pointer of type (`#1547 <https://github.com/ros2/rclcpp/issues/1547>`_) (`#1548 <https://github.com/ros2/rclcpp/issues/1548>`_)
+* Contributors: Jacob Perron, Simon Honigmann, Tomoya Fujita
+
+2.3.0 (2020-12-09)
+------------------
+* Update QD to QL 1 (`#1480 <https://github.com/ros2/rclcpp/issues/1480>`_)
+* Add performance tests for parameter transport (`#1470 <https://github.com/ros2/rclcpp/issues/1470>`_)
+* Add benchmarks for node parameters interface (`#1470 <https://github.com/ros2/rclcpp/issues/1470>`_)
+* Fix NodeOptions copy constructor (`#1376 <https://github.com/ros2/rclcpp/issues/1376>`_) (`#1451 <https://github.com/ros2/rclcpp/issues/1451>`_)
+* Avoid reference cycle to fix memory leak (`#1301 <https://github.com/ros2/rclcpp/issues/1301>`_) (`#1450 <https://github.com/ros2/rclcpp/issues/1450>`_)
+* Bump rclcpp packages to Quality Level 2 (`#1445 <https://github.com/ros2/rclcpp/issues/1445>`_) (`#1446 <https://github.com/ros2/rclcpp/issues/1446>`_)
+* Added executor benchmark tests (`#1413 <https://github.com/ros2/rclcpp/issues/1413>`_)
+* Add service and client benchmarks (`#1425 <https://github.com/ros2/rclcpp/issues/1425>`_)
+* Set CMakeLists to only use default rmw for benchmarks (`#1427 <https://github.com/ros2/rclcpp/issues/1427>`_)
+* Initial benchmark tests for rclcpp::init/shutdown create/destroy node (`#1411 <https://github.com/ros2/rclcpp/issues/1411>`_)
+* Use global namespace for parameter events subscription topic (`#1257 <https://github.com/ros2/rclcpp/issues/1257>`_) (`#1261 <https://github.com/ros2/rclcpp/issues/1261>`_)
+* Refactor test CMakeLists.txt (`#1422 <https://github.com/ros2/rclcpp/issues/1422>`_) and moving rosidl_generate_interfaces_call (`#1424 <https://github.com/ros2/rclcpp/issues/1424>`_)  (`#1437 <https://github.com/ros2/rclcpp/issues/1437>`_)
+* Update tracetools' QL in rclcpp's QD (`#1428 <https://github.com/ros2/rclcpp/issues/1428>`_) (`#1430 <https://github.com/ros2/rclcpp/issues/1430>`_)
+* Add coverage statement (`#1367 <https://github.com/ros2/rclcpp/issues/1367>`_)
+* Update tracetools' QL to 2 in rclcpp's QD (`#1187 <https://github.com/ros2/rclcpp/issues/1187>`_)
+* Fix reference to rclcpp in its QD (`#1161 <https://github.com/ros2/rclcpp/issues/1161>`_)
+* Clear members for StaticExecutorEntitiesCollector to avoid shared_ptr dependency (`#1303 <https://github.com/ros2/rclcpp/issues/1303>`_)
+* Increase test timeouts of slow running tests with rmw_connext_cpp (`#1400 <https://github.com/ros2/rclcpp/issues/1400>`_)
+* Make sure to clean the external client/service handle. (`#1296 <https://github.com/ros2/rclcpp/issues/1296>`_)
+* Increase coverage of WaitSetTemplate (`#1368 <https://github.com/ros2/rclcpp/issues/1368>`_)
+* Increase coverage of guard_condition.cpp to 100% (`#1369 <https://github.com/ros2/rclcpp/issues/1369>`_)
+* Tests for LoanedMessage with mocked loaned message publisher (`#1366 <https://github.com/ros2/rclcpp/issues/1366>`_)
+* Add unit tests for qos and qos_event files (`#1352 <https://github.com/ros2/rclcpp/issues/1352>`_)
+* Finish coverage of publisher API (`#1365 <https://github.com/ros2/rclcpp/issues/1365>`_)
+* Finish API coverage on executors (`#1364 <https://github.com/ros2/rclcpp/issues/1364>`_)
+* Only exchange intra_process waitable if nonnull (`#1317 <https://github.com/ros2/rclcpp/issues/1317>`_)
+* Add test for ParameterService (`#1355 <https://github.com/ros2/rclcpp/issues/1355>`_)
+* Add time API coverage tests (`#1347 <https://github.com/ros2/rclcpp/issues/1347>`_)
+* Add timer coverage tests (`#1363 <https://github.com/ros2/rclcpp/issues/1363>`_)
+* Add in additional tests for parameter_client.cpp coverage.
+* Minor fixes to the parameter_service.cpp file.
+* Improve test publisher - zero qos history depth value exception (`#1360 <https://github.com/ros2/rclcpp/issues/1360>`_)
+* Covered resolve_use_intra_process (`#1359 <https://github.com/ros2/rclcpp/issues/1359>`_)
+* Improve test_subscription_options (`#1358 <https://github.com/ros2/rclcpp/issues/1358>`_)
+* Add in more tests for init_options coverage (`#1353 <https://github.com/ros2/rclcpp/issues/1353>`_)
+* Test the remaining node public API (`#1342 <https://github.com/ros2/rclcpp/issues/1342>`_)
+* Complete coverage of Parameter and ParameterValue API (`#1344 <https://github.com/ros2/rclcpp/issues/1344>`_)
+* Add in more tests for the utilities (`#1349 <https://github.com/ros2/rclcpp/issues/1349>`_)
+* Add in two more tests for expand_topic_or_service_name (`#1350 <https://github.com/ros2/rclcpp/issues/1350>`_)
+* Add tests for node_options API (`#1343 <https://github.com/ros2/rclcpp/issues/1343>`_)
+* Add in more coverage for expand_topic_or_service_name. (`#1346 <https://github.com/ros2/rclcpp/issues/1346>`_)
+* Add coverage tests graph_listener (`#1330 <https://github.com/ros2/rclcpp/issues/1330>`_)
+* Add executor unit tests `#1336 <https://github.com/ros2/rclcpp/issues/1336>`_ (`#1395 <https://github.com/ros2/rclcpp/issues/1395>`_)
+* Add coverage for client API (`#1329 <https://github.com/ros2/rclcpp/issues/1329>`_)
+* Increase service coverage (`#1332 <https://github.com/ros2/rclcpp/issues/1332>`_)
+* Add ostream test for FutureReturnCode (`#1327 <https://github.com/ros2/rclcpp/issues/1327>`_) (`#1393 <https://github.com/ros2/rclcpp/issues/1393>`_)
+* Increase coverage of publisher/subscription API (`#1325 <https://github.com/ros2/rclcpp/issues/1325>`_)
+* Add coverage for missing API (except executors) (`#1326 <https://github.com/ros2/rclcpp/issues/1326>`_)
+* Add coverage tests context functions (`#1321 <https://github.com/ros2/rclcpp/issues/1321>`_)
+* Increase coverage of node_interfaces, including with mocking rcl errors (`#1322 <https://github.com/ros2/rclcpp/issues/1322>`_)
+* Add coverage for wait_set_policies (`#1316 <https://github.com/ros2/rclcpp/issues/1316>`_)
+* Add tests type_support module (`#1308 <https://github.com/ros2/rclcpp/issues/1308>`_)
+* Replace std_msgs with test_msgs in executors test (`#1310 <https://github.com/ros2/rclcpp/issues/1310>`_)
+* Adding tests basic getters (`#1291 <https://github.com/ros2/rclcpp/issues/1291>`_)
+* Refactor Subscription Topic Statistics Tests (`#1281 <https://github.com/ros2/rclcpp/issues/1281>`_)
+* Fix topic stats test, wait for more messages, only check the ones with samples (`#1274 <https://github.com/ros2/rclcpp/issues/1274>`_)
+* Fixes for unit tests that fail under cyclonedds (`#1270 <https://github.com/ros2/rclcpp/issues/1270>`_)
+* initialize_logging\_ should be copied (`#1272 <https://github.com/ros2/rclcpp/issues/1272>`_)
+* Ability to configure domain_id via InitOptions (`#1165 <https://github.com/ros2/rclcpp/issues/1165>`_)
+* Simplify and fix allocator memory strategy unit test for connext (`#1252 <https://github.com/ros2/rclcpp/issues/1252>`_)
+* Increase timeouts for connext for long tests (`#1253 <https://github.com/ros2/rclcpp/issues/1253>`_)
+* Adjust test_static_executor_entities_collector for rmw_connext_cpp (`#1251 <https://github.com/ros2/rclcpp/issues/1251>`_)
+* Fix failing test with Connext since it doesn't wait for discovery (`#1246 <https://github.com/ros2/rclcpp/issues/1246>`_)
+* Fix node graph test with Connext and CycloneDDS returning actual data (`#1245 <https://github.com/ros2/rclcpp/issues/1245>`_)
+* Unittests for memory strategy files, except allocator_memory_strategy (`#1189 <https://github.com/ros2/rclcpp/issues/1189>`_)
+* EXPECT_THROW_EQ and ASSERT_THROW_EQ macros for unittests (`#1232 <https://github.com/ros2/rclcpp/issues/1232>`_)
+* Parameterize test executors for all executor types (`#1222 <https://github.com/ros2/rclcpp/issues/1222>`_) (`#1386 <https://github.com/ros2/rclcpp/issues/1386>`_)
+* Derive and throw exception in spin_some spin_all for StaticSingleThreadedExecutor (`#1385 <https://github.com/ros2/rclcpp/issues/1385>`_)
+* Add unit test for static_executor_entities_collector (`#1221 <https://github.com/ros2/rclcpp/issues/1221>`_)
+* Unit tests for allocator_memory_strategy.cpp part 2 (`#1198 <https://github.com/ros2/rclcpp/issues/1198>`_)
+* Unit tests for allocator_memory_strategy.hpp (`#1197 <https://github.com/ros2/rclcpp/issues/1197>`_)
+* Unit tests for node interfaces (`#1202 <https://github.com/ros2/rclcpp/issues/1202>`_)
+* Unit tests for some header-only functions/classes (`#1181 <https://github.com/ros2/rclcpp/issues/1181>`_)
+* Add unit tests for logging functionality (`#1184 <https://github.com/ros2/rclcpp/issues/1184>`_)
+* Fix rclcpp::NodeOptions::operator= (`#1211 <https://github.com/ros2/rclcpp/issues/1211>`_)
+* Check period duration in create_wall_timer (`#1178 <https://github.com/ros2/rclcpp/issues/1178>`_)
+* Throw exception if rcl_timer_init fails (`#1179 <https://github.com/ros2/rclcpp/issues/1179>`_)
+* Remove finalization of guard_condition from GraphListener::__shutdown() (`#1401 <https://github.com/ros2/rclcpp/issues/1401>`_)
+* Contributors: Alejandro Hernández Cordero, Chen Lihui, Chris Lalancette, Christophe Bedard, Devin Bonnie, Dirk Thomas, Jacob Perron, Jorge Perez, Louise Poubel, Michel Hidalgo, Scott K Logan, Stephen Brawner, tomoya
+
+2.2.0 (2020-10-07)
+------------------
+* Fix implementation of NodeOptions::use_global_arguments() (`#1176 <https://github.com/ros2/rclcpp/issues/1176>`_) (`#1372 <https://github.com/ros2/rclcpp/issues/1372>`_)
+* Fix conversion of negative durations to messages (`#1188 <https://github.com/ros2/rclcpp/issues/1188>`_) (`#1371 <https://github.com/ros2/rclcpp/issues/1371>`_)
+* Call vector.erase with end iterator overload (`#1314 <https://github.com/ros2/rclcpp/issues/1314>`_) (`#1380 <https://github.com/ros2/rclcpp/issues/1380>`_)
+* Check waitable for nullptr during constructor (`#1315 <https://github.com/ros2/rclcpp/issues/1315>`_) (`#1379 <https://github.com/ros2/rclcpp/issues/1379>`_)
+* Fix pub/sub count API tests. (`#1203 <https://github.com/ros2/rclcpp/issues/1203>`_) (`#1319 <https://github.com/ros2/rclcpp/issues/1319>`_)
+* Reorganize test directory and split CMakeLists.txt (`#1173 <https://github.com/ros2/rclcpp/issues/1173>`_) (`#1262 <https://github.com/ros2/rclcpp/issues/1262>`_)
+* Add operator!= for duration (`#1236 <https://github.com/ros2/rclcpp/issues/1236>`_) (`#1278 <https://github.com/ros2/rclcpp/issues/1278>`_)
+* Contributors: Ivan Santiago Paunovic, Jacob Perron, Jannik Abbenseth, Johannes Meyer, Michel Hidalgo, Stephen Brawner
+
+2.1.0 (2020-08-03)
+------------------
+* Warn about unused result of add_on_set_parameters_callback (`#1238 <https://github.com/ros2/rclcpp/issues/1238>`_) (`#1244 <https://github.com/ros2/rclcpp/issues/1244>`_)
+* Add missing RCLCPP_PUBLIC to ~StaticExecutorEntitiesCollector (`#1227 <https://github.com/ros2/rclcpp/issues/1227>`_) (`#1228 <https://github.com/ros2/rclcpp/issues/1228>`_)
+* Remove recreation of entities_collector (`#1217 <https://github.com/ros2/rclcpp/issues/1217>`_) (`#1224 <https://github.com/ros2/rclcpp/issues/1224>`_)
+* Contributors: Jacob Perron, brawner
+
+2.0.2 (2020-07-07)
+------------------
+* Link against thread library where necessary (`#1210 <https://github.com/ros2/rclcpp/issues/1210>`_) (`#1214 <https://github.com/ros2/rclcpp/issues/1214>`_)
+* Fix exception message on rcl_clock_init (`#1182 <https://github.com/ros2/rclcpp/issues/1182>`_) (`#1193 <https://github.com/ros2/rclcpp/issues/1193>`_)
+* Contributors: Dirk Thomas, tomoya
+
+2.0.1 (2020-06-23)
+------------------
+* Add create_publisher include to create_subscription (`#1180 <https://github.com/ros2/rclcpp/issues/1180>`_) (`#1192 <https://github.com/ros2/rclcpp/issues/1192>`_)
+* Fix get_node_time_source_interface() docstring (`#988 <https://github.com/ros2/rclcpp/issues/988>`_) (`#1185 <https://github.com/ros2/rclcpp/issues/1185>`_)
+* Fixed doxygen warnings (`#1163 <https://github.com/ros2/rclcpp/issues/1163>`_) (`#1191 <https://github.com/ros2/rclcpp/issues/1191>`_)
+* Check if context is valid when looping in spin_some (`#1167 <https://github.com/ros2/rclcpp/issues/1167>`_)
+* Fix spin_until_future_complete: check spinning value (`#1023 <https://github.com/ros2/rclcpp/issues/1023>`_)
+  Make Executor::spin_once_impl private before backporting, to avoid API compatibility issues
+* Add check for invalid topic statistics publish period (`#1151 <https://github.com/ros2/rclcpp/issues/1151>`_) (`#1172 <https://github.com/ros2/rclcpp/issues/1172>`_)
+* Contributors: Alejandro Hernández Cordero, Devin Bonnie, DongheeYe, Ivan Santiago Paunovic, Jacob Perron, Stephen Brawner
+
+2.0.0 (2020-06-01)
+------------------
+* Added missing virtual destructors. (`#1149 <https://github.com/ros2/rclcpp/issues/1149>`_)
+* Fixed a test which was using different types on the same topic. (`#1150 <https://github.com/ros2/rclcpp/issues/1150>`_)
+* Made ``test_rate`` more reliable on Windows and improve error output when it fails (`#1146 <https://github.com/ros2/rclcpp/issues/1146>`_)
+* Added Security Vulnerability Policy pointing to REP-2006. (`#1130 <https://github.com/ros2/rclcpp/issues/1130>`_)
+* Added missing header in ``logging_mutex.cpp``. (`#1145 <https://github.com/ros2/rclcpp/issues/1145>`_)
+* Changed the WaitSet API to pass a shared pointer by value instead than by const reference when possible. (`#1141 <https://github.com/ros2/rclcpp/issues/1141>`_)
+* Changed ``SubscriptionBase::get_subscription_handle() const`` to return a shared pointer to const value. (`#1140 <https://github.com/ros2/rclcpp/issues/1140>`_)
+* Extended the lifetime of ``rcl_publisher_t`` by holding onto the shared pointer in order to avoid a use after free situation. (`#1119 <https://github.com/ros2/rclcpp/issues/1119>`_)
+* Improved some docblocks (`#1127 <https://github.com/ros2/rclcpp/issues/1127>`_)
+* Fixed a lock-order-inversion (potential deadlock) (`#1135 <https://github.com/ros2/rclcpp/issues/1135>`_)
+* Fixed a potential Construction/Destruction order problem between global contexts vector and Context of static lifetime (`#1132 <https://github.com/ros2/rclcpp/issues/1132>`_)
+* Contributors: Alejandro Hernández Cordero, Chris Lalancette, Ivan Santiago Paunovic, Michel Hidalgo, tomoya
+
+1.1.0 (2020-05-26)
+------------------
+* Deprecate set_on_parameters_set_callback (`#1123 <https://github.com/ros2/rclcpp/issues/1123>`_)
+* Expose get_service_names_and_types_by_node from rcl in rclcpp (`#1131 <https://github.com/ros2/rclcpp/issues/1131>`_)
+* Fix thread safety issues related to logging (`#1125 <https://github.com/ros2/rclcpp/issues/1125>`_)
+* Make sure rmw_publisher_options is initialized in to_rcl_publisher_options (`#1099 <https://github.com/ros2/rclcpp/issues/1099>`_)
+* Remove empty lines within method signatures (`#1128 <https://github.com/ros2/rclcpp/issues/1128>`_)
+* Add API review March 2020 document (`#1031 <https://github.com/ros2/rclcpp/issues/1031>`_)
+* Improve documentation (`#1106 <https://github.com/ros2/rclcpp/issues/1106>`_)
+* Make test multi threaded executor more reliable (`#1105 <https://github.com/ros2/rclcpp/issues/1105>`_)
+* Fixed rep links and added more details to dependencies in quality declaration (`#1116 <https://github.com/ros2/rclcpp/issues/1116>`_)
+* Update quality declarations to reflect version 1.0 (`#1115 <https://github.com/ros2/rclcpp/issues/1115>`_)
+* Contributors: Alejandro Hernández Cordero, ChenYing Kuo, Claire Wang, Dirk Thomas, Ivan Santiago Paunovic, William Woodall, Stephen Brawner
+
+1.0.0 (2020-05-12)
+------------------
+* Remove MANUAL_BY_NODE liveliness API (`#1107 <https://github.com/ros2/rclcpp/issues/1107>`_)
+* Use rosidl_default_generators dependency in test (`#1114 <https://github.com/ros2/rclcpp/issues/1114>`_)
+* Make sure to include what you use (`#1112 <https://github.com/ros2/rclcpp/issues/1112>`_)
+* Mark flaky test with xfail: TestMultiThreadedExecutor (`#1109 <https://github.com/ros2/rclcpp/issues/1109>`_)
+* Contributors: Chris Lalancette, Ivan Santiago Paunovic, Karsten Knese, Louise Poubel
+
+0.9.1 (2020-05-08)
+------------------
+* Fix tests that were not properly torn down (`#1073 <https://github.com/ros2/rclcpp/issues/1073>`_)
+* Added docblock in rclcpp (`#1103 <https://github.com/ros2/rclcpp/issues/1103>`_)
+* Added Quality declaration: rclcpp, rclpp_action, rclcpp_components andrclcpp_lifecycle (`#1100 <https://github.com/ros2/rclcpp/issues/1100>`_)
+* Use RCL_RET_SERVICE_TAKE_FAILED and not RCL_RET_CLIENT_TAKE_FAILED when checking a request take (`#1101 <https://github.com/ros2/rclcpp/issues/1101>`_)
+* Update comment about return value in Executor::get_next_ready_executable (`#1085 <https://github.com/ros2/rclcpp/issues/1085>`_)
+* Contributors: Alejandro Hernández Cordero, Christophe Bedard, Devin Bonnie, Ivan Santiago Paunovic
+
+0.9.0 (2020-04-29)
+------------------
+* Serialized message move constructor (`#1097 <https://github.com/ros2/rclcpp/issues/1097>`_)
+* Enforce a precedence for wildcard matching in parameter overrides. (`#1094 <https://github.com/ros2/rclcpp/issues/1094>`_)
+* Add serialized_message.hpp header (`#1095 <https://github.com/ros2/rclcpp/issues/1095>`_)
+* Add received message age metric to topic statistics (`#1080 <https://github.com/ros2/rclcpp/issues/1080>`_)
+* Deprecate redundant namespaces (`#1083 <https://github.com/ros2/rclcpp/issues/1083>`_)
+* Export targets in addition to include directories / libraries (`#1088 <https://github.com/ros2/rclcpp/issues/1088>`_)
+* Ensure logging is initialized just once (`#998 <https://github.com/ros2/rclcpp/issues/998>`_)
+* Adapt subscription traits to rclcpp::SerializedMessage (`#1092 <https://github.com/ros2/rclcpp/issues/1092>`_)
+* Protect subscriber_statistics_collectors\_ with a mutex (`#1084 <https://github.com/ros2/rclcpp/issues/1084>`_)
+* Remove unused test variable (`#1087 <https://github.com/ros2/rclcpp/issues/1087>`_)
+* Use serialized message (`#1081 <https://github.com/ros2/rclcpp/issues/1081>`_)
+* Integrate topic statistics (`#1072 <https://github.com/ros2/rclcpp/issues/1072>`_)
+* Fix rclcpp interface traits test (`#1086 <https://github.com/ros2/rclcpp/issues/1086>`_)
+* Generate node interfaces' getters and traits (`#1069 <https://github.com/ros2/rclcpp/issues/1069>`_)
+* Use composition for serialized message (`#1082 <https://github.com/ros2/rclcpp/issues/1082>`_)
+* Dnae adas/serialized message (`#1075 <https://github.com/ros2/rclcpp/issues/1075>`_)
+* Reflect changes in rclcpp API (`#1079 <https://github.com/ros2/rclcpp/issues/1079>`_)
+* Fix build regression (`#1078 <https://github.com/ros2/rclcpp/issues/1078>`_)
+* Add NodeDefault option for enabling topic statistics (`#1074 <https://github.com/ros2/rclcpp/issues/1074>`_)
+* Topic Statistics: Add SubscriptionTopicStatistics class (`#1050 <https://github.com/ros2/rclcpp/issues/1050>`_)
+* Add SubscriptionOptions for topic statistics (`#1057 <https://github.com/ros2/rclcpp/issues/1057>`_)
+* Remove warning message from failing to register default callback (`#1067 <https://github.com/ros2/rclcpp/issues/1067>`_)
+* Create a default warning for qos incompatibility (`#1051 <https://github.com/ros2/rclcpp/issues/1051>`_)
+* Add WaitSet class and modify entities to work without executor (`#1047 <https://github.com/ros2/rclcpp/issues/1047>`_)
+* Include what you use (`#1059 <https://github.com/ros2/rclcpp/issues/1059>`_)
+* Rename rosidl_generator_cpp namespace to rosidl_runtime_cpp (`#1060 <https://github.com/ros2/rclcpp/issues/1060>`_)
+* Changed rosidl_generator_c/cpp to rosidl_runtime_c/cpp (`#1014 <https://github.com/ros2/rclcpp/issues/1014>`_)
+* Use constexpr for endpoint type name (`#1055 <https://github.com/ros2/rclcpp/issues/1055>`_)
+* Add InvalidParameterTypeException (`#1027 <https://github.com/ros2/rclcpp/issues/1027>`_)
+* Support for ON_REQUESTED_INCOMPATIBLE_QOS and ON_OFFERED_INCOMPATIBLE_QOS events (`#924 <https://github.com/ros2/rclcpp/issues/924>`_)
+* Fixup clang warning (`#1040 <https://github.com/ros2/rclcpp/issues/1040>`_)
+* Adding a "static" single threaded executor (`#1034 <https://github.com/ros2/rclcpp/issues/1034>`_)
+* Add equality operators for QoS profile (`#1032 <https://github.com/ros2/rclcpp/issues/1032>`_)
+* Remove extra vertical whitespace (`#1030 <https://github.com/ros2/rclcpp/issues/1030>`_)
+* Switch IntraProcessMessage to test_msgs/Empty (`#1017 <https://github.com/ros2/rclcpp/issues/1017>`_)
+* Add new type of exception that may be thrown during creation of publisher/subscription (`#1026 <https://github.com/ros2/rclcpp/issues/1026>`_)
+* Don't check lifespan on publisher QoS (`#1002 <https://github.com/ros2/rclcpp/issues/1002>`_)
+* Fix get_parameter_tyeps of AsyncPrameterClient results are always empty (`#1019 <https://github.com/ros2/rclcpp/issues/1019>`_)
+* Cleanup node interfaces includes (`#1016 <https://github.com/ros2/rclcpp/issues/1016>`_)
+* Add ifdefs to remove tracing-related calls if tracing is disabled (`#1001 <https://github.com/ros2/rclcpp/issues/1001>`_)
+* Include missing header in node_graph.cpp (`#994 <https://github.com/ros2/rclcpp/issues/994>`_)
+* Add missing includes of logging.hpp (`#995 <https://github.com/ros2/rclcpp/issues/995>`_)
+* Zero initialize publisher GID in subscription intra process callback (`#1011 <https://github.com/ros2/rclcpp/issues/1011>`_)
+* Removed ament_cmake dependency (`#989 <https://github.com/ros2/rclcpp/issues/989>`_)
+* Switch to using new rcutils_strerror (`#993 <https://github.com/ros2/rclcpp/issues/993>`_)
+* Ensure all rclcpp::Clock accesses are thread-safe
+* Use a PIMPL for rclcpp::Clock implementation
+* Replace rmw_implementation for rmw dependency in package.xml (`#990 <https://github.com/ros2/rclcpp/issues/990>`_)
+* Add missing service callback registration tracepoint (`#986 <https://github.com/ros2/rclcpp/issues/986>`_)
+* Rename rmw_topic_endpoint_info_array count to size (`#996 <https://github.com/ros2/rclcpp/issues/996>`_)
+* Implement functions to get publisher and subcription informations like QoS policies from topic name (`#960 <https://github.com/ros2/rclcpp/issues/960>`_)
+* Code style only: wrap after open parenthesis if not in one line (`#977 <https://github.com/ros2/rclcpp/issues/977>`_)
+* Accept taking an rvalue ref future in spin_until_future_complete (`#971 <https://github.com/ros2/rclcpp/issues/971>`_)
+* Allow node clock use in logging macros (`#969 <https://github.com/ros2/rclcpp/issues/969>`_) (`#970 <https://github.com/ros2/rclcpp/issues/970>`_)
+* Change order of deprecated and visibility attributes (`#968 <https://github.com/ros2/rclcpp/issues/968>`_)
+* Deprecated is_initialized() (`#967 <https://github.com/ros2/rclcpp/issues/967>`_)
+* Don't specify calling convention in std::_Binder template (`#952 <https://github.com/ros2/rclcpp/issues/952>`_)
+* Added missing include to logging.hpp (`#964 <https://github.com/ros2/rclcpp/issues/964>`_)
+* Assigning make_shared result to variables in test (`#963 <https://github.com/ros2/rclcpp/issues/963>`_)
+* Fix unused parameter warning (`#962 <https://github.com/ros2/rclcpp/issues/962>`_)
+* Stop retaining ownership of the rcl context in GraphListener (`#946 <https://github.com/ros2/rclcpp/issues/946>`_)
+* Clear sub contexts when starting another init-shutdown cycle (`#947 <https://github.com/ros2/rclcpp/issues/947>`_)
+* Avoid possible UB in Clock jump callbacks (`#954 <https://github.com/ros2/rclcpp/issues/954>`_)
+* Handle unknown global ROS arguments (`#951 <https://github.com/ros2/rclcpp/issues/951>`_)
+* Mark get_clock() as override to fix clang warnings (`#939 <https://github.com/ros2/rclcpp/issues/939>`_)
+* Create node clock calls const (try 2) (`#922 <https://github.com/ros2/rclcpp/issues/922>`_)
+* Fix asserts on shared_ptr::use_count; expects long, got uint32 (`#936 <https://github.com/ros2/rclcpp/issues/936>`_)
+* Use absolute topic name for parameter events (`#929 <https://github.com/ros2/rclcpp/issues/929>`_)
+* Add enable_rosout into NodeOptions. (`#900 <https://github.com/ros2/rclcpp/issues/900>`_)
+* Removing "virtual", adding "override" keywords (`#897 <https://github.com/ros2/rclcpp/issues/897>`_)
+* Use weak_ptr to store context in GraphListener (`#906 <https://github.com/ros2/rclcpp/issues/906>`_)
+* Complete published event message when declaring a parameter (`#928 <https://github.com/ros2/rclcpp/issues/928>`_)
+* Fix duration.cpp lint error (`#930 <https://github.com/ros2/rclcpp/issues/930>`_)
+* Intra-process subscriber should use RMW actual qos. (ros2`#913 <https://github.com/ros2/rclcpp/issues/913>`_) (`#914 <https://github.com/ros2/rclcpp/issues/914>`_)
+* Type conversions fixes (`#901 <https://github.com/ros2/rclcpp/issues/901>`_)
+* Add override keyword to functions
+* Remove unnecessary virtual keywords
+* Only check for new work once in spin_some (`#471 <https://github.com/ros2/rclcpp/issues/471>`_) (`#844 <https://github.com/ros2/rclcpp/issues/844>`_)
+* Add addition/subtraction assignment operators to Time (`#748 <https://github.com/ros2/rclcpp/issues/748>`_)
+* Contributors: Alberto Soragna, Alejandro Hernández Cordero, Barry Xu, Chris Lalancette, Christophe Bedard, Claire Wang, Dan Rose, DensoADAS, Devin Bonnie, Dino Hüllmann, Dirk Thomas, DongheeYe, Emerson Knapp, Ivan Santiago Paunovic, Jacob Perron, Jaison Titus, Karsten Knese, Matt Schickler, Miaofei Mei, Michel Hidalgo, Mikael Arguedas, Monika Idzik, Prajakta Gokhale, Roger Strain, Scott K Logan, Sean Kelly, Stephen Brawner, Steven Macenski, Steven! Ragnarök, Todd Malsbary, Tomoya Fujita, William Woodall, Zachary Michaels
+
 0.8.3 (2019-11-19)
 ------------------
 

rclcpp/CMakeLists.txt

@@ -2,18 +2,22 @@ cmake_minimum_required(VERSION 3.5)
 
 project(rclcpp)
 
+find_package(Threads REQUIRED)
+
 find_package(ament_cmake_ros REQUIRED)
 find_package(builtin_interfaces REQUIRED)
+find_package(libstatistics_collector REQUIRED)
 find_package(rcl REQUIRED)
 find_package(rcl_interfaces REQUIRED)
 find_package(rcl_yaml_param_parser REQUIRED)
 find_package(rcpputils REQUIRED)
+find_package(rcutils REQUIRED)
 find_package(rmw REQUIRED)
-find_package(rmw_implementation REQUIRED)
 find_package(rosgraph_msgs REQUIRED)
-find_package(rosidl_generator_cpp REQUIRED)
+find_package(rosidl_runtime_cpp REQUIRED)
 find_package(rosidl_typesupport_c REQUIRED)
 find_package(rosidl_typesupport_cpp REQUIRED)
+find_package(statistics_msgs REQUIRED)
 find_package(tracetools REQUIRED)
 
 # Default to C++14
@@ -21,11 +25,13 @@ if(NOT CMAKE_CXX_STANDARD)
   set(CMAKE_CXX_STANDARD 14)
 endif()
 if(CMAKE_COMPILER_IS_GNUCXX OR CMAKE_CXX_COMPILER_ID MATCHES "Clang")
-  add_compile_options(-Wall -Wextra -Wpedantic)
+  # About -Wno-sign-conversion: With Clang, -Wconversion implies -Wsign-conversion. There are a number of
+  # implicit sign conversions in rclcpp and gtest.cc, see https://ci.ros2.org/job/ci_osx/9265/.
+  # Hence disabling -Wsign-conversion for now until all those have eventually been fixed.
+  # (from https://github.com/ros2/rclcpp/pull/1188#issuecomment-650229140)
+  add_compile_options(-Wall -Wextra -Wconversion -Wno-sign-conversion -Wpedantic -Wnon-virtual-dtor -Woverloaded-virtual)
 endif()
 
-include_directories(include)
-
 set(${PROJECT_NAME}_SRCS
   src/rclcpp/any_executable.cpp
   src/rclcpp/callback_group.cpp
@@ -33,23 +39,32 @@ set(${PROJECT_NAME}_SRCS
   src/rclcpp/clock.cpp
   src/rclcpp/context.cpp
   src/rclcpp/contexts/default_context.cpp
+  src/rclcpp/detail/mutex_two_priorities.cpp
   src/rclcpp/detail/rmw_implementation_specific_payload.cpp
   src/rclcpp/detail/rmw_implementation_specific_publisher_payload.cpp
   src/rclcpp/detail/rmw_implementation_specific_subscription_payload.cpp
+  src/rclcpp/detail/utilities.cpp
   src/rclcpp/duration.cpp
   src/rclcpp/event.cpp
-  src/rclcpp/exceptions.cpp
+  src/rclcpp/exceptions/exceptions.cpp
+  src/rclcpp/executable_list.cpp
   src/rclcpp/executor.cpp
   src/rclcpp/executors.cpp
   src/rclcpp/expand_topic_or_service_name.cpp
   src/rclcpp/executors/multi_threaded_executor.cpp
   src/rclcpp/executors/single_threaded_executor.cpp
+  src/rclcpp/executors/static_executor_entities_collector.cpp
+  src/rclcpp/executors/static_single_threaded_executor.cpp
+  src/rclcpp/future_return_code.cpp
   src/rclcpp/graph_listener.cpp
+  src/rclcpp/guard_condition.cpp
   src/rclcpp/init_options.cpp
   src/rclcpp/intra_process_manager.cpp
   src/rclcpp/logger.cpp
+  src/rclcpp/logging_mutex.cpp
   src/rclcpp/memory_strategies.cpp
   src/rclcpp/memory_strategy.cpp
+  src/rclcpp/message_info.cpp
   src/rclcpp/node.cpp
   src/rclcpp/node_options.cpp
   src/rclcpp/node_interfaces/node_base.cpp
@@ -71,6 +86,8 @@ set(${PROJECT_NAME}_SRCS
   src/rclcpp/publisher_base.cpp
   src/rclcpp/qos.cpp
   src/rclcpp/qos_event.cpp
+  src/rclcpp/serialization.cpp
+  src/rclcpp/serialized_message.cpp
   src/rclcpp/service.cpp
   src/rclcpp/signal_handler.cpp
   src/rclcpp/subscription_base.cpp
@@ -80,6 +97,7 @@ set(${PROJECT_NAME}_SRCS
   src/rclcpp/timer.cpp
   src/rclcpp/type_support.cpp
   src/rclcpp/utilities.cpp
+  src/rclcpp/wait_set_policies/detail/write_preferring_read_write_lock.cpp
   src/rclcpp/waitable.cpp
 )
 
@@ -90,32 +108,84 @@ configure_file(
   COPYONLY
 )
 # generate header with logging macros
-set(python_code
+set(python_code_logging
   "import em"
   "em.invoke(['-o', 'include/rclcpp/logging.hpp', '${CMAKE_CURRENT_SOURCE_DIR}/resource/logging.hpp.em'])")
-string(REPLACE ";" "$<SEMICOLON>" python_code "${python_code}")
+string(REPLACE ";" "$<SEMICOLON>" python_code_logging "${python_code_logging}")
 add_custom_command(OUTPUT include/rclcpp/logging.hpp
   COMMAND ${CMAKE_COMMAND} -E make_directory "include/rclcpp"
-  COMMAND ${PYTHON_EXECUTABLE} ARGS -c "${python_code}"
+  COMMAND ${PYTHON_EXECUTABLE} ARGS -c "${python_code_logging}"
   DEPENDS "${CMAKE_CURRENT_BINARY_DIR}/logging.hpp.em.watch"
   COMMENT "Expanding logging.hpp.em"
   VERBATIM
 )
 list(APPEND ${PROJECT_NAME}_SRCS
   include/rclcpp/logging.hpp)
-include_directories("${CMAKE_CURRENT_BINARY_DIR}/include")
+
+file(GLOB interface_files "include/rclcpp/node_interfaces/node_*_interface.hpp")
+foreach(interface_file ${interface_files})
+  get_filename_component(interface_name ${interface_file} NAME_WE)
+
+  # "watch" template for changes
+  configure_file(
+    "resource/interface_traits.hpp.em"
+    "${CMAKE_CURRENT_BINARY_DIR}/${interface_name}_traits.hpp.em.watch"
+    COPYONLY
+  )
+  set(python_${interface_name}_traits
+    "import em"
+    "em.invoke(['-D', 'interface_name = \\'${interface_name}\\'', '-o', 'include/rclcpp/node_interfaces/${interface_name}_traits.hpp', '${CMAKE_CURRENT_SOURCE_DIR}/resource/interface_traits.hpp.em'])")
+  string(REPLACE ";" "$<SEMICOLON>" python_${interface_name}_traits "${python_${interface_name}_traits}")
+  add_custom_command(OUTPUT include/rclcpp/node_interfaces/${interface_name}_traits.hpp
+    COMMAND ${CMAKE_COMMAND} -E make_directory "include/rclcpp/node_interfaces"
+    COMMAND ${PYTHON_EXECUTABLE} ARGS -c "${python_${interface_name}_traits}"
+    DEPENDS "${CMAKE_CURRENT_BINARY_DIR}/${interface_name}_traits.hpp.em.watch"
+    COMMENT "Expanding interface_traits.hpp.em into ${interface_name}_traits.hpp"
+    VERBATIM
+  )
+  list(APPEND ${PROJECT_NAME}_SRCS
+    include/rclcpp/node_interfaces/${interface_name}_traits.hpp)
+
+  # "watch" template for changes
+  configure_file(
+    "resource/get_interface.hpp.em"
+    "get_${interface_name}.hpp.em.watch"
+    COPYONLY
+  )
+  set(python_get_${interface_name}
+    "import em"
+    "em.invoke(['-D', 'interface_name = \\'${interface_name}\\'', '-o', 'include/rclcpp/node_interfaces/get_${interface_name}.hpp', '${CMAKE_CURRENT_SOURCE_DIR}/resource/get_interface.hpp.em'])")
+  string(REPLACE ";" "$<SEMICOLON>" python_get_${interface_name} "${python_get_${interface_name}}")
+  add_custom_command(OUTPUT include/rclcpp/node_interfaces/get_${interface_name}.hpp
+    COMMAND ${CMAKE_COMMAND} -E make_directory "include/rclcpp/node_interfaces"
+    COMMAND ${PYTHON_EXECUTABLE} ARGS -c "${python_get_${interface_name}}"
+    DEPENDS "${CMAKE_CURRENT_BINARY_DIR}/get_${interface_name}.hpp.em.watch"
+    COMMENT "Expanding get_interface.hpp.em into get_${interface_file}.hpp"
+    VERBATIM
+  )
+  list(APPEND ${PROJECT_NAME}_SRCS
+    include/rclcpp/node_interfaces/get_${interface_name}.hpp)
+endforeach()
 
 add_library(${PROJECT_NAME}
   ${${PROJECT_NAME}_SRCS})
+target_include_directories(${PROJECT_NAME} PUBLIC
+  "$<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/include>"
+  "$<BUILD_INTERFACE:${CMAKE_CURRENT_BINARY_DIR}/include>"
+  "$<INSTALL_INTERFACE:include>")
+target_link_libraries(${PROJECT_NAME} ${CMAKE_THREAD_LIBS_INIT})
 # specific order: dependents before dependencies
 ament_target_dependencies(${PROJECT_NAME}
+  "libstatistics_collector"
   "rcl"
   "rcl_yaml_param_parser"
   "rcpputils"
+  "rcutils"
   "builtin_interfaces"
   "rosgraph_msgs"
   "rosidl_typesupport_cpp"
-  "rosidl_generator_cpp"
+  "rosidl_runtime_cpp"
+  "statistics_msgs"
   "tracetools"
 )
 
@@ -125,7 +195,7 @@ target_compile_definitions(${PROJECT_NAME}
   PRIVATE "RCLCPP_BUILDING_LIBRARY")
 
 install(
-  TARGETS ${PROJECT_NAME}
+  TARGETS ${PROJECT_NAME} EXPORT ${PROJECT_NAME}
   ARCHIVE DESTINATION lib
   LIBRARY DESTINATION lib
   RUNTIME DESTINATION bin
@@ -134,367 +204,26 @@ install(
 # specific order: dependents before dependencies
 ament_export_include_directories(include)
 ament_export_libraries(${PROJECT_NAME})
+ament_export_targets(${PROJECT_NAME})
 
-ament_export_dependencies(ament_cmake)
+ament_export_dependencies(libstatistics_collector)
 ament_export_dependencies(rcl)
 ament_export_dependencies(rcpputils)
+ament_export_dependencies(rcutils)
 ament_export_dependencies(builtin_interfaces)
 ament_export_dependencies(rosgraph_msgs)
 ament_export_dependencies(rosidl_typesupport_cpp)
 ament_export_dependencies(rosidl_typesupport_c)
-ament_export_dependencies(rosidl_generator_cpp)
+ament_export_dependencies(rosidl_runtime_cpp)
 ament_export_dependencies(rcl_yaml_param_parser)
+ament_export_dependencies(statistics_msgs)
 ament_export_dependencies(tracetools)
 
 if(BUILD_TESTING)
-  find_package(ament_cmake_gtest REQUIRED)
   find_package(ament_lint_auto REQUIRED)
   ament_lint_auto_find_test_dependencies()
 
-  find_package(rmw_implementation_cmake REQUIRED)
-
-  find_package(test_msgs REQUIRED)
-
-  include(cmake/rclcpp_add_build_failure_test.cmake)
-
-  add_definitions(-DTEST_RESOURCES_DIRECTORY="${CMAKE_CURRENT_BINARY_DIR}/test/resources")
-
-  ament_add_gtest(test_client test/test_client.cpp)
-  if(TARGET test_client)
-    ament_target_dependencies(test_client
-      "rcl_interfaces"
-      "rmw"
-      "rosidl_generator_cpp"
-      "rosidl_typesupport_cpp"
-    )
-    target_link_libraries(test_client ${PROJECT_NAME})
-  endif()
-  ament_add_gtest(test_create_timer test/test_create_timer.cpp)
-  if(TARGET test_create_timer)
-    ament_target_dependencies(test_create_timer
-      "rcl_interfaces"
-      "rmw"
-      "rcl"
-      "rosidl_generator_cpp"
-      "rosidl_typesupport_cpp"
-    )
-    target_link_libraries(test_create_timer ${PROJECT_NAME})
-    target_include_directories(test_create_timer PRIVATE test/)
-  endif()
-  ament_add_gtest(test_expand_topic_or_service_name test/test_expand_topic_or_service_name.cpp)
-  if(TARGET test_expand_topic_or_service_name)
-    ament_target_dependencies(test_expand_topic_or_service_name
-      "rcl_interfaces"
-      "rmw"
-      "rosidl_generator_cpp"
-      "rosidl_typesupport_cpp"
-    )
-    target_link_libraries(test_expand_topic_or_service_name ${PROJECT_NAME})
-  endif()
-  ament_add_gtest(test_function_traits test/test_function_traits.cpp)
-  if(TARGET test_function_traits)
-    ament_target_dependencies(test_function_traits
-      "rcl_interfaces"
-      "rmw"
-      "rosidl_generator_cpp"
-      "rosidl_typesupport_cpp"
-    )
-  endif()
-  ament_add_gmock(test_intra_process_manager test/test_intra_process_manager.cpp)
-  if(TARGET test_intra_process_manager)
-    ament_target_dependencies(test_intra_process_manager
-      "rcl"
-      "rcl_interfaces"
-      "rmw"
-      "rosidl_generator_cpp"
-      "rosidl_typesupport_cpp"
-    )
-    target_link_libraries(test_intra_process_manager ${PROJECT_NAME})
-  endif()
-  ament_add_gtest(test_ring_buffer_implementation test/test_ring_buffer_implementation.cpp)
-  if(TARGET test_ring_buffer_implementation)
-    ament_target_dependencies(test_ring_buffer_implementation
-      "rcl_interfaces"
-      "rmw"
-      "rosidl_generator_cpp"
-      "rosidl_typesupport_cpp"
-    )
-    target_link_libraries(test_ring_buffer_implementation ${PROJECT_NAME})
-  endif()
-  ament_add_gtest(test_intra_process_buffer test/test_intra_process_buffer.cpp)
-  if(TARGET test_intra_process_buffer)
-    ament_target_dependencies(test_intra_process_buffer
-      "rcl_interfaces"
-      "rmw"
-      "rosidl_generator_cpp"
-      "rosidl_typesupport_cpp"
-    )
-    target_link_libraries(test_intra_process_buffer ${PROJECT_NAME})
-  endif()
-
-  ament_add_gtest(test_loaned_message test/test_loaned_message.cpp)
-  ament_target_dependencies(test_loaned_message
-    "test_msgs"
-  )
-  target_link_libraries(test_loaned_message ${PROJECT_NAME})
-
-  ament_add_gtest(test_node test/test_node.cpp TIMEOUT 240)
-  if(TARGET test_node)
-    ament_target_dependencies(test_node
-      "rcl_interfaces"
-      "rcpputils"
-      "rmw"
-      "rosidl_generator_cpp"
-      "rosidl_typesupport_cpp"
-    )
-    target_link_libraries(test_node ${PROJECT_NAME})
-  endif()
-
-  ament_add_gtest(test_node_interfaces__get_node_interfaces
-    test/node_interfaces/test_get_node_interfaces.cpp)
-  if(TARGET test_node_interfaces__get_node_interfaces)
-    target_link_libraries(test_node_interfaces__get_node_interfaces ${PROJECT_NAME})
-  endif()
-
-  # TODO(wjwwood): reenable these build failure tests when I can get Jenkins to ignore their output
-  # rclcpp_add_build_failure_test(build_failure__get_node_topics_interface_const_ref_rclcpp_node
-  #   test/node_interfaces/test_does_not_compile/get_node_topics_interface_const_ref_rclcpp_node.cpp)
-  # target_link_libraries(build_failure__get_node_topics_interface_const_ref_rclcpp_node
-  #   ${PROJECT_NAME})
-
-  # rclcpp_add_build_failure_test(build_failure__get_node_topics_interface_const_ptr_rclcpp_node
-  #   test/node_interfaces/test_does_not_compile/get_node_topics_interface_const_ptr_rclcpp_node.cpp)
-  # target_link_libraries(build_failure__get_node_topics_interface_const_ptr_rclcpp_node
-  #   ${PROJECT_NAME})
-
-  # rclcpp_add_build_failure_test(build_failure__get_node_topics_interface_const_ref_wrapped_node
-  #   test/node_interfaces/test_does_not_compile/get_node_topics_interface_const_ref_wrapped_node.cpp)
-  # target_link_libraries(build_failure__get_node_topics_interface_const_ref_rclcpp_node
-  #   ${PROJECT_NAME})
-
-  # rclcpp_add_build_failure_test(build_failure__get_node_topics_interface_const_ptr_wrapped_node
-  #   test/node_interfaces/test_does_not_compile/get_node_topics_interface_const_ptr_wrapped_node.cpp)
-  # target_link_libraries(build_failure__get_node_topics_interface_const_ptr_rclcpp_node
-  #   ${PROJECT_NAME})
-
-  ament_add_gtest(test_node_global_args test/test_node_global_args.cpp)
-  if(TARGET test_node_global_args)
-    ament_target_dependencies(test_node_global_args
-      "rcl_interfaces"
-      "rmw"
-      "rosidl_generator_cpp"
-      "rosidl_typesupport_cpp"
-    )
-    target_link_libraries(test_node_global_args ${PROJECT_NAME})
-  endif()
-  ament_add_gtest(test_node_options test/test_node_options.cpp)
-  if(TARGET test_node_options)
-    ament_target_dependencies(test_node_options "rcl")
-    target_link_libraries(test_node_options ${PROJECT_NAME})
-  endif()
-  ament_add_gtest(test_parameter_client test/test_parameter_client.cpp)
-  if(TARGET test_parameter_client)
-    ament_target_dependencies(test_parameter_client
-      "rcl_interfaces"
-    )
-    target_link_libraries(test_parameter_client ${PROJECT_NAME})
-  endif()
-  ament_add_gtest(test_parameter_events_filter test/test_parameter_events_filter.cpp)
-  if(TARGET test_parameter_events_filter)
-    ament_target_dependencies(test_parameter_events_filter
-      "rcl_interfaces"
-      "rmw"
-      "rosidl_generator_cpp"
-      "rosidl_typesupport_cpp"
-    )
-    target_link_libraries(test_parameter_events_filter ${PROJECT_NAME})
-  endif()
-  ament_add_gtest(test_parameter test/test_parameter.cpp)
-  if(TARGET test_parameter)
-    ament_target_dependencies(test_parameter
-      "rcl_interfaces"
-      "rmw"
-      "rosidl_generator_cpp"
-      "rosidl_typesupport_cpp"
-    )
-    target_link_libraries(test_parameter ${PROJECT_NAME})
-  endif()
-  ament_add_gtest(test_parameter_map test/test_parameter_map.cpp)
-  if(TARGET test_parameter_map)
-    target_link_libraries(test_parameter_map ${PROJECT_NAME})
-  endif()
-  ament_add_gtest(test_publisher test/test_publisher.cpp)
-  if(TARGET test_publisher)
-    ament_target_dependencies(test_publisher
-      "rcl_interfaces"
-      "rmw"
-      "rosidl_generator_cpp"
-      "rosidl_typesupport_cpp"
-    )
-    target_link_libraries(test_publisher ${PROJECT_NAME})
-  endif()
-  ament_add_gtest(test_publisher_subscription_count_api test/test_publisher_subscription_count_api.cpp)
-  if(TARGET test_publisher_subscription_count_api)
-    ament_target_dependencies(test_publisher_subscription_count_api
-      "rcl_interfaces"
-      "rmw"
-      "rosidl_generator_cpp"
-      "rosidl_typesupport_cpp"
-    )
-    target_link_libraries(test_publisher_subscription_count_api ${PROJECT_NAME})
-  endif()
-  ament_add_gtest(test_rate test/test_rate.cpp)
-  if(TARGET test_rate)
-    ament_target_dependencies(test_rate
-      "rcl_interfaces"
-      "rmw"
-      "rosidl_generator_cpp"
-      "rosidl_typesupport_cpp"
-    )
-    target_link_libraries(test_rate
-      ${PROJECT_NAME}
-    )
-  endif()
-  ament_add_gtest(test_serialized_message_allocator test/test_serialized_message_allocator.cpp)
-  if(TARGET test_serialized_message_allocator)
-    ament_target_dependencies(test_serialized_message_allocator
-      test_msgs
-    )
-    target_link_libraries(test_serialized_message_allocator
-      ${PROJECT_NAME}
-    )
-  endif()
-  ament_add_gtest(test_service test/test_service.cpp)
-  if(TARGET test_service)
-    ament_target_dependencies(test_service
-      "rcl_interfaces"
-      "rmw"
-      "rosidl_generator_cpp"
-      "rosidl_typesupport_cpp"
-    )
-    target_link_libraries(test_service ${PROJECT_NAME})
-  endif()
-  ament_add_gtest(test_subscription test/test_subscription.cpp)
-  if(TARGET test_subscription)
-    ament_target_dependencies(test_subscription
-      "rcl_interfaces"
-      "rmw"
-      "rosidl_generator_cpp"
-      "rosidl_typesupport_cpp"
-    )
-    target_link_libraries(test_subscription ${PROJECT_NAME})
-  endif()
-  ament_add_gtest(test_subscription_publisher_count_api test/test_subscription_publisher_count_api.cpp)
-  if(TARGET test_subscription_publisher_count_api)
-    ament_target_dependencies(test_subscription_publisher_count_api
-      "rcl_interfaces"
-      "rmw"
-      "rosidl_generator_cpp"
-      "rosidl_typesupport_cpp"
-    )
-    target_link_libraries(test_subscription_publisher_count_api ${PROJECT_NAME})
-  endif()
-  ament_add_gtest(test_subscription_traits test/test_subscription_traits.cpp)
-  if(TARGET test_subscription_traits)
-    ament_target_dependencies(test_subscription_traits
-      "rcl"
-      "test_msgs"
-    )
-  endif()
-  ament_add_gtest(test_find_weak_nodes test/test_find_weak_nodes.cpp)
-  if(TARGET test_find_weak_nodes)
-    ament_target_dependencies(test_find_weak_nodes
-      "rcl"
-    )
-    target_link_libraries(test_find_weak_nodes ${PROJECT_NAME})
-  endif()
-
-  set(append_library_dirs "${CMAKE_CURRENT_BINARY_DIR}")
-  if(WIN32)
-    set(append_library_dirs "${append_library_dirs}/$<CONFIG>")
-  endif()
-
-  ament_add_gtest(test_externally_defined_services test/test_externally_defined_services.cpp)
-  ament_target_dependencies(test_externally_defined_services
-    "rcl"
-    "test_msgs"
-  )
-  target_link_libraries(test_externally_defined_services ${PROJECT_NAME})
-
-  ament_add_gtest(test_duration test/test_duration.cpp
-    APPEND_LIBRARY_DIRS "${append_library_dirs}")
-  if(TARGET test_duration)
-    ament_target_dependencies(test_duration
-      "rcl")
-    target_link_libraries(test_duration ${PROJECT_NAME})
-  endif()
-
-  ament_add_gtest(test_executor test/test_executor.cpp
-    APPEND_LIBRARY_DIRS "${append_library_dirs}")
-  if(TARGET test_executor)
-    ament_target_dependencies(test_executor
-      "rcl")
-    target_link_libraries(test_executor ${PROJECT_NAME})
-  endif()
-
-  ament_add_gtest(test_logger test/test_logger.cpp)
-  target_link_libraries(test_logger ${PROJECT_NAME})
-
-  ament_add_gmock(test_logging test/test_logging.cpp)
-  target_link_libraries(test_logging ${PROJECT_NAME})
-
-  ament_add_gtest(test_time test/test_time.cpp
-    APPEND_LIBRARY_DIRS "${append_library_dirs}")
-  if(TARGET test_time)
-    ament_target_dependencies(test_time
-      "rcl")
-    target_link_libraries(test_time ${PROJECT_NAME})
-  endif()
-
-  ament_add_gtest(test_timer test/test_timer.cpp
-    APPEND_LIBRARY_DIRS "${append_library_dirs}")
-  if(TARGET test_timer)
-    ament_target_dependencies(test_timer
-      "rcl")
-    target_link_libraries(test_timer ${PROJECT_NAME})
-  endif()
-
-  ament_add_gtest(test_time_source test/test_time_source.cpp
-    APPEND_LIBRARY_DIRS "${append_library_dirs}")
-  if(TARGET test_time_source)
-    ament_target_dependencies(test_time_source
-      "rcl")
-    target_link_libraries(test_time_source ${PROJECT_NAME})
-  endif()
-
-  ament_add_gtest(test_utilities test/test_utilities.cpp
-    APPEND_LIBRARY_DIRS "${append_library_dirs}")
-  if(TARGET test_utilities)
-    ament_target_dependencies(test_utilities
-      "rcl")
-    target_link_libraries(test_utilities ${PROJECT_NAME})
-  endif()
-
-  ament_add_gtest(test_init test/test_init.cpp
-    APPEND_LIBRARY_DIRS "${append_library_dirs}")
-  if(TARGET test_init)
-    ament_target_dependencies(test_init
-      "rcl")
-    target_link_libraries(test_init ${PROJECT_NAME})
-  endif()
-
-  ament_add_gtest(test_multi_threaded_executor test/executors/test_multi_threaded_executor.cpp
-    APPEND_LIBRARY_DIRS "${append_library_dirs}")
-  if(TARGET test_multi_threaded_executor)
-    ament_target_dependencies(test_multi_threaded_executor
-      "rcl")
-    target_link_libraries(test_multi_threaded_executor ${PROJECT_NAME})
-  endif()
-
-  # Install test resources
-  install(
-    DIRECTORY test/resources
-    DESTINATION ${CMAKE_CURRENT_BINARY_DIR}/test)
+  add_subdirectory(test)
 endif()
 
 ament_package()

rclcpp/QUALITY_DECLARATION.md

@@ -0,0 +1,222 @@
+This document is a declaration of software quality for the `rclcpp` package, based on the guidelines in [REP-2004](https://www.ros.org/reps/rep-2004.html).
+
+# rclcpp Quality Declaration
+
+The package `rclcpp` claims to be in the **Quality Level 1** category when it is used with a **Quality Level 1** middleware.
+
+Below are the rationales, notes, and caveats for this claim, organized by each requirement listed in the [Package Quality Categories in REP-2004](https://www.ros.org/reps/rep-2004.html) of the ROS2 developer guide.
+
+## Version Policy [1]
+
+### Version Scheme [1.i]
+
+`rclcpp` uses `semver` according to the recommendation for ROS Core packages in the [ROS 2 Developer Guide](https://docs.ros.org/en/foxy/Contributing/Developer-Guide.html#versioning).
+
+### Version Stability [1.ii]
+
+`rclcpp` is at a stable version, i.e. `>= 1.0.0`.
+The current version can be found in its [package.xml](package.xml), and its change history can be found in its [CHANGELOG](CHANGELOG.rst).
+
+### Public API Declaration [1.iii]
+
+All symbols in the installed headers are considered part of the public API.
+
+Except for the exclusions listed below, all installed headers are in the `include` directory of the package, headers in any other folders are not installed and considered private.
+Headers under the folder `experimental` are not considered part of the public API as they have not yet been stabilized. These symbols are namespaced `rclcpp::experimental`.
+Headers under the folder `detail` are not considered part of the public API and are subject to change without notice. These symbols are namespaced `rclcpp::detail`.
+
+### API Stability Policy [1.iv]
+
+`rclcpp` will not break public API within a released ROS distribution, i.e. no major releases once the ROS distribution is released.
+
+### ABI Stability Policy [1.v]
+
+`rclcpp` contains C++ code and therefore must be concerned with ABI stability, and will maintain ABI stability within a ROS distribution.
+
+### ABI and ABI Stability Within a Released ROS Distribution [1.vi]
+
+`rclcpp` will not break API nor ABI within a released ROS distribution, i.e. no major releases once the ROS distribution is released.
+
+## Change Control Process [2]
+
+`rclcpp` follows the recommended guidelines for ROS Core packages in the [ROS 2 Developer Guide](https://docs.ros.org/en/foxy/Contributing/Developer-Guide.html#change-control-process).
+
+### Change Requests [2.i]
+
+All changes will occur through a pull request, check [ROS 2 Developer Guide](https://docs.ros.org/en/foxy/Contributing/Developer-Guide.html#change-control-process) for additional information.
+
+### Contributor Origin [2.ii]
+
+This package uses DCO as its confirmation of contributor origin policy. More information can be found in [CONTRIBUTING](../CONTRIBUTING.md).
+
+### Peer Review Policy [2.iii]
+
+All pull requests will be peer-reviewed, check [ROS 2 Developer Guide](https://docs.ros.org/en/foxy/Contributing/Developer-Guide.html#change-control-process) for additional information.
+
+### Continuous Integration [2.iv]
+
+All pull requests must pass CI on all [tier 1 platforms](https://www.ros.org/reps/rep-2000.html#support-tiers)
+
+Though there are no nightly jobs for foxy outside of linux, each change is tested on ci.ros2.org.
+* [linux-aarch64](https://ci.ros2.org/job/ci_linux-aarch64)
+* [linux](https://ci.ros2.org/job/ci_linux)
+* [mac_osx](https://ci.ros2.org/job/ci_osx)
+* [windows](https://ci.ros2.org/job/ci_windows)
+
+###  Documentation Policy [2.v]
+
+All pull requests must resolve related documentation changes before merging.
+
+## Documentation [3]
+
+### Feature Documentation [3.i]
+
+`rclcpp` has a [feature list](http://docs.ros2.org/foxy/api/rclcpp/) and each item in the list links to the corresponding feature documentation. There is documentation for all of the features, and new features require documentation before being added.
+
+### Public API Documentation [3.ii]
+
+The API is publicly available in its [ROS 2 API documentation](http://docs.ros2.org/foxy/api/rclcpp/).
+
+### License [3.iii]
+
+The license for `rclcpp` is Apache 2.0, and a summary is in each source file, the type is declared in the [`package.xml`](./package.xml) manifest file, and a full copy of the license is in the [`LICENSE`](../LICENSE) file.
+
+There is an automated test which runs a linter that ensures each file has a license statement. [Here](http://build.ros2.org/view/Fpr/job/Fpr__rclcpp__ubuntu_focal_amd64/lastCompletedBuild/testReport/rclcpp/) can be found a list with the latest results of the various linters being run on the package.
+
+### Copyright Statements [3.iv]
+
+The copyright holders each provide a statement of copyright in each source code file in `rclcpp`.
+
+There is an automated test which runs a linter that ensures each file has at least one copyright statement. Latest linter result report can be seen [here](http://build.ros2.org/view/Fpr/job/Fpr__rclcpp__ubuntu_focal_amd64/lastCompletedBuild/testReport/rclcpp/copyright/).
+
+## Testing [4]
+
+### Feature Testing [4.i]
+
+Each feature in `rclcpp` has corresponding tests which simulate typical usage, and they are located in the [`test`](https://github.com/ros2/rclcpp/tree/foxy/test) directory.
+New features are required to have tests before being added.
+
+Though there are no nightly jobs for foxy outside of linux, each change is tested on ci.ros2.org.
+* [linux-aarch64](https://ci.ros2.org/job/ci_linux-aarch64)
+* [linux](https://ci.ros2.org/job/ci_linux)
+* [mac_osx](https://ci.ros2.org/job/ci_osx)
+* [windows](https://ci.ros2.org/job/ci_windows)
+
+### Public API Testing [4.ii]
+
+Each part of the public API has tests, and new additions or changes to the public API require tests before being added.
+The tests aim to cover both typical usage and corner cases, but are quantified by contributing to code coverage.
+
+### Coverage [4.iii]
+
+`rclcpp` follows the recommendations for ROS Core packages in the [ROS 2 Developer Guide](https://docs.ros.org/en/foxy/Contributing/Developer-Guide.html#code-coverage), and opts to use line coverage instead of branch coverage.
+
+This includes:
+
+- tracking and reporting line coverage statistics
+- achieving and maintaining a reasonable branch line coverage (90-100%)
+- no lines are manually skipped in coverage calculations
+
+Changes are required to make a best effort to keep or increase coverage before being accepted, but decreases are allowed if properly justified and accepted by reviewers.
+
+Current coverage statistics can be viewed [here](https://ci.ros2.org/job/nightly_linux_foxy_coverage/lastCompletedBuild/cobertura/src_ros2_rclcpp_rclcpp_src_rclcpp/). A description of how coverage statistics are calculated is summarized in this page ["ROS 2 Onboarding Guide"](https://docs.ros.org/en/foxy/Contributing/Developer-Guide.html#note-on-coverage-runs).
+
+`rclcpp` has a line coverage `>= 95%`, which is calculated over all directories within `rclcpp` with the exception of the `experimental` directory.
+
+### Performance [4.iv]
+
+`rclcpp` follows the recommendations for performance testing of C/C++ code in the [ROS 2 Developer Guide](https://docs.ros.org/en/foxy/Contributing/Developer-Guide.html#performance), and opts to do performance analysis on each release rather than each change.
+
+The performance tests of `rclcpp` are located in the [test/benchmark directory](https://github.com/ros2/rclcpp/tree/foxy/rclcpp/test/benchmark).
+
+System level performance benchmarks that cover features of `rclcpp` can be found at:
+* [Benchmarks](http://build.ros2.org/view/Fci/job/Fci__benchmark_ubuntu_focal_amd64/BenchmarkTable/)
+* [Performance](http://build.ros2.org/view/Fci/job/Fci__nightly-performance_ubuntu_focal_amd64/lastCompletedBuild/)
+
+Changes that introduce regressions in performance must be adequately justified in order to be accepted and merged.
+
+### Linters and Static Analysis [4.v]
+
+`rclcpp` uses and passes all the ROS2 standard linters and static analysis tools for a C++ package as described in the [ROS 2 Developer Guide](https://docs.ros.org/en/foxy/Contributing/Developer-Guide.html#linters-and-static-analysis). Passing implies there are no linter/static errors when testing against CI of supported platforms.
+
+Currently nightly test results can be seen [here](http://build.ros2.org/view/Fpr/job/Fpr__rclcpp__ubuntu_focal_amd64/lastCompletedBuild/testReport/rclcpp).
+
+## Dependencies [5]
+
+Below are evaluations of each of `rclcpp`'s run-time and build-time dependencies that have been determined to influence the quality.
+
+It has several "buildtool" dependencies, which do not affect the resulting quality of the package, because they do not contribute to the public library API.
+
+It also has several test dependencies, which do not affect the resulting quality of the package, because they are only used to build and run the test code.
+
+### Direct and Optional Runtime ROS Dependencies [5.i]/[5.ii]
+
+`rclcpp` has the following runtime ROS dependencies:
+
+#### `libstatistics_collector`
+
+The `libstatistics_collector` package provides lightweight aggregation utilities to collect statistics and measure message metrics.
+
+It is **Quality Level 1**, see its [Quality Declaration document](https://github.com/ros-tooling/libstatistics_collector/tree/foxy-devel/QUALITY_DECLARATION.md).
+
+#### `rcl`
+
+`rcl` a library to support implementation of language specific ROS 2 Client Libraries.
+
+It is **Quality Level 1**, see its [Quality Declaration document](https://github.com/ros2/rcl/blob/foxy/rcl/QUALITY_DECLARATION.md).
+
+#### `rcl_yaml_param_parser`
+
+The `rcl_yaml_param_parser` package provides an API that is used to parse YAML configuration files which may be used to configure ROS and specific nodes.
+
+It is **Quality Level 1**, see its [Quality Declaration document](https://github.com/ros2/rcl/tree/foxy/rcl_yaml_param_parser/QUALITY_DECLARATION.md).
+
+#### `rcpputils`
+
+The `rcpputils` package provides an API which contains common utilities and data structures useful when programming in C++.
+
+It is **Quality Level 1**, see its [Quality Declaration document](https://github.com/ros2/rcpputils/blob/foxy/QUALITY_DECLARATION.md).
+
+#### `rcutils`
+
+The `rcutils` package provides an API which contains common utilities and data structures useful when programming in C.
+
+It is **Quality Level 1**, see its [Quality Declaration document](https://github.com/ros2/rcutils/blob/foxy/QUALITY_DECLARATION.md).
+
+#### `rmw`
+
+`rmw` is the ROS 2 middleware library.
+
+It is **Quality Level 1**, see its [Quality Declaration document](https://github.com/ros2/rmw/blob/foxy/rmw/QUALITY_DECLARATION.md).
+
+#### `statistics_msgs`
+
+The `statistics_msgs` package contains ROS 2 message definitions for reporting statistics for topics and system resources.
+
+It is **Quality Level 1**, see its [Quality Declaration document](https://github.com/ros2/rcl_interfaces/blob/foxy/statistics_msgs/QUALITY_DECLARATION.md).
+
+#### `tracetools`
+
+The `tracetools` package provides utilities for instrumenting the code in `rclcpp` so that it may be traced for debugging and performance analysis.
+
+It is **Quality Level 1**, see its [Quality Declaration document](https://gitlab.com/ros-tracing/ros2_tracing/-/blob/foxy/tracetools/QUALITY_DECLARATION.md).
+
+### Direct Runtime non-ROS Dependency [5.iii]
+
+`rclcpp` has no run-time or build-time dependencies that need to be considered for this declaration.
+
+## Platform Support [6]
+
+`rclcpp` supports all of the tier 1 platforms as described in [REP-2000](https://www.ros.org/reps/rep-2000.html#support-tiers), and tests each change against all of them.
+
+Though there are no nightly jobs for foxy outside of linux, each change is tested on ci.ros2.org.
+* [linux-aarch64](https://ci.ros2.org/job/ci_linux-aarch64)
+* [linux](https://ci.ros2.org/job/ci_linux)
+* [mac_osx](https://ci.ros2.org/job/ci_osx)
+* [windows](https://ci.ros2.org/job/ci_windows)
+
+## Security
+
+### Vulnerability Disclosure Policy [7.i]
+
+This package conforms to the Vulnerability Disclosure Policy in [REP-2006](https://www.ros.org/reps/rep-2006.html).

rclcpp/README.md

@@ -0,0 +1,9 @@
+# `rclcpp`
+
+The ROS client library in C++.
+
+Visit the [rclcpp API documentation](http://docs.ros2.org/latest/api/rclcpp/) for a complete list of its main components and features.
+
+## Quality Declaration
+
+This package claims to be in the **Quality Level 1** category, see the [Quality Declaration](QUALITY_DECLARATION.md) for more details.

rclcpp/doc/api_review_march_2020.md

@@ -0,0 +1,437 @@
+# API Review for `rclcpp` from March 2020
+
+## Notes
+
+### Off-Topic Questions
+
+> [rclcpp_action] There exists a thread-safe and non-thread-safe way to get the goal result from an action client. We probably want to remove the public interface to the non-thread safe call (or consolidate somehow): https://github.com/ros2/rclcpp/issues/955
+
+`rclcpp_action` is out of scope atm.
+
+**Notes from 2020-03-19**: To be handled in separate API review.
+
+## Architecture
+
+### Calling Syntax and Keeping Node-like Class APIs in Sync
+
+> Currently, much of the API is exposed via the `rclcpp::Node` class, and due to the nature of the current architecture there is a lot of repeated code to expose these methods and then call the implementations which are in other classes like `rclcpp::node_interfaces::NodeTopics`, for example.
+>
+> Also, we have other versions of the class `rclcpp::Node` with different semantics and interfaces, like `rclcpp_lifecycle::LifecycleNode`, and we have been having trouble keeping the interface provided there up to date with how things are done in `rclcpp::Node`. Since `LifecycleNode` has a different API from `Node` in some important cases, it does not just inherit from `Node`.
+>
+> There are two main proposals (as I see it) to try and address this issue, either (a) break up the functionality in `Node` so that it is in separate classes and make `Node` multiple inherit from those classes, and then `LifecycleNode` could selectively inherit from those as well, or (b) change our calling convention from `node->do_thing(...)` to be `do_thing(node, ...)`.
+>
+> For (a) which commonly referred to as the [Policy Based Design Pattern](https://en.wikipedia.org/wiki/Modern_C%2B%2B_Design#Policy-based_design), we'd be reversing previous design decisions which we discussed at length where we decided to use composition over inheritance for various reasons.
+> One of the reasons was testing, with the theory that having simpler separate interfaces we could more easily mock them as needed for testing.
+> The testing goal would still be met, either by keeping the "node_interface" classes as-is or by mocking the classes that node would multiple inherit from, however it's harder to indicate that a function needs a class that multiple inherits from several classes but not others.
+> Also having interdependency between the classes which are inherited from is a bit complicated in this design pattern.
+>
+> For (b), we would be changing how we recommend all code be written (not a trivial thing to do at all), because example code like `auto pub = node->create_publsiher(...);` would be come `auto pub = create_publisher(node, ...);`.
+> This has some distinct advantages, however, in that it allows us to write these functions, like `create_publisher(node, ...)`, so that the node argument can be any class that meets the criteria of the function.
+> That not only means that when we add a feature it automatically works with `Node` and `LifecycleNode` without adding anything to them, it also means that user defined `Node`-like classes will also work, even if they do not inherit from or provide the complete interface for `rclcpp::Node`.
+> Another major downside of this approach is discoverability of the API when using auto-completion in text editors, as `node-><tab>` will often give you a list of methods to explore, but with the new calling convention, there's not way to get an auto complete for code who's first argument is a `Node`-like class.
+>
+> Both of the above approaches address some of the main concerns, which are: keeping `Node` and `LifecycleNode` in sync, reducing the size of the `Node` class so it is more easily maintained, documented, and so that related functions are grouped more clearly.
+
+- https://github.com/ros2/rclcpp/issues/898
+- https://github.com/ros2/rclcpp/issues/509
+- https://github.com/ros2/rclcpp/issues/855
+- https://github.com/ros2/rclcpp/issues/985
+  - subnode feature is in rclcpp::Node only, complicating "node using" API designs
+- http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2014/n4174.pdf
+- https://en.wikipedia.org/wiki/Uniform_Function_Call_Syntax#C++_proposal
+  - "Many programmers are tempted to write member functions to get the benefits of the member function syntax (e.g. "dot-autocomplete" to list member functions);[6] however, this leads to excessive coupling between classes.[7]"
+
+**Suggested Action**: Document the discussion and defer until Foxy.
+
+**Notes from 2020-03-19**:
+
+- Another version of (b) could be to have classes that are constructed with node, e.g. `Publisher(node, ...)` rather than `node->create_publisher(...)`
+- (tfoote) interface class? `NodeInterface<NodeLike>::something(node_like)`
+  - DRY?
+  - `NodeInterface<LifecycleNode>::<tab>` -> only life cycle node methods
+- (karsten) use interface classes directly, e.g. node->get_X_interface()->do_thing()
+- (dirk) use macros to add methods to class
+  - Question: Do we want tab-completable API (specifically list of member functions)?
+- Question: Is consistency in calling between core and non-core features more important than tab-completion?
+- Add better example of adding new feature and not needing to touch `rclcpp::Node`.
+- (dirk) methods and free functions not mutually exclusive.
+
+### Scoped Versus Non-Scoped Entities (e.g. Publishers/Subscriptions)
+
+> Currently, Publisher and Subscription (and similar entities) are scoped, meaning that when they are created they are added to the ROS graph as a side effect, and when they are let out of scope they remove themselves from the graph too.
+> Additionally, they necessarily have shared state with the system, for instance when you are spinning on a node, the executor shares ownership of the Subscriptions with the user.
+> Therefore, the Subscription only gets removed when both the user and executor are done with it.
+>
+> This shared ownership is accomplished with the use of shared pointers and weak pointers.
+>
+> There are a few concerns here, (a) use of shared pointers confuses users, (b) overhead of shared pointers and lack of an ability to use these classes on the stack rather than the heap, and (c) complexity of shutdown of an entity from the users perspective.
+>
+> For (a), some users are overwhelmed by the need to use a shared pointer.
+> In ROS 1 this was avoided by having a class which itself just thinly wraps a shared pointer (see: https://github.com/ros/ros_comm/blob/ac9f88c59a676ca6895e13445fc7d71f398ebe1f/clients/roscpp/include/ros/subscriber.h#L108-L111).
+> This could be achieved in ROS 2 either by doing the same with a wrapper class (at the expense of lots of repeated code), or by eliminating the need for using shared ownership.
+>
+> For (b), for some use cases, especially resource constrained / real-time / safety-critical environments, requiring these classes to be on the heap rather than the stack is at least inconvenient.
+> Additionally, there is a cost associated with using shared pointers, in the storage of shared state and in some implementation the use of locks or at least atomics for thread-safety.
+>
+> For (c), this is the most concerning drawback, because right now when a user lets their shared pointer to a, for example, Subscription go out of scope, a post condition is not that the Subscription is destroyed, nor that it has been removed from the graph.
+> In stead, the behavior is more like "at some point in the future the Subscription will be destroyed and removed from the graph, when the system is done with it".
+> This isn't a very satisfactory contract, as some users may wish to know when the Subscription has been deleted, but cannot easily know that.
+>
+> The benefit to the shared state is a safety net for users.
+> The alternative would be to document that a Subscription, again for example, cannot be deleted until the system is done with it.
+> We'd basically be pushing the responsibility onto the user to ensure the shared ownership is handled properly by the execution of their application, i.e. they create the Subscription, share a reference with the system (adding it by reference to an executor, for example), and they have to make sure the system is done with it before deleting the Subscription.
+>
+>Separately, from the above points, there is the related concern of forcing the user to keep a copy of their entities in scope, whether it be with a shared pointer or a class wrapping one.
+> There is the desire to create it and forget it in some cases.
+> The downside to this is that if/when the user wants to destroy the entity, they have no way of doing that as they have no handle or unique way to address the entity.
+>
+> One proposed solution would be to have a set of "named X" APIs, e.g. `create_named_subscription` rather than just `create_subscription`.
+> This would allow the user to address the Subscription in the future in order to obtain a new reference to it or delete it.
+
+- https://github.com/ros2/rclcpp/issues/506
+- https://github.com/ros2/rclcpp/issues/726
+
+**Suggested Action**: Consolidate to a single issue, and defer.
+
+**Notes from 2020-03-23**:
+
+- (chris) Putting ownership mechanics on user is hard.
+- (dirk) add documentation clearly outlining ownership
+- (shane) warn on unused to catch issues with immediately deleted items
+- (tfoote) debugging output for destruction so it easy to see when reviewing logs
+- (chris) possible to create API that checks for destruction
+  - (william) might lead to complex synchronization issues
+- (tfoote) could add helper classes to make scoped things non-scoped
+  - (shane) concerned that there is no longer "one good way" to do it
+
+### Allow QoS to be configured externally, like we allow remapping of topic names
+
+> Suggestion from @stonier: allow the qos setting on a topic to be changed externally at startup, similar to how we do topic remapping (e.g., do it on the command-line using appropriate syntax).
+>
+> To keep the syntax manageable, we might just allow profiles to be picked.
+
+- https://github.com/ros2/rclcpp/issues/239
+
+**Suggested Action**: Update issue, defer for now.
+
+**Notes from 2020-03-19**:
+
+- (wjwwood) it depends on the QoS setting, but many don't make sense, mostly because they can change some of the behaviors of underlying API
+- (dirk) Should developers expose a parameter instead?
+- (multiple) should be a feature that makes configuring them (after opt-in) consistent
+- (jacob) customers feedback was that this was expected, surprised it was not allowed
+- (karsten) could limit to profiles
+
+## Init/shutdown and Context
+
+### Consider renaming `rclcpp::ok()`
+
+> Old discussion to rename `rclcpp::ok()` to something more specific, like `rclcpp::is_not_shutdown()` or the corollary `rclcpp::is_shutdown()`.
+
+- https://github.com/ros2/rclcpp/issues/3
+
+**Suggested Action**: Defer.
+
+**Notes from 2020-03-19**:
+
+- (shane) preference to not have a negative in the function name
+
+## Executor
+
+### Exposing Scheduling of Tasks in Executor and a Better Default
+
+> Currently there is a hard coded procedure for handling ready tasks in the executor, first timers, then subscriptions, and so on.
+> This scheduling is not fair and results in non-deterministic behavior and starvation issues.
+>
+> We should provide a better default scheduling which is fairer and ideally deterministic, something like round-robin or FIFO.
+>
+> Additionally, we should make it easier to let the user override the scheduling logic in the executor.
+
+- https://github.com/ros2/rclcpp/pull/614
+- https://github.com/ros2/rclcpp/issues/633
+- https://github.com/ros2/rclcpp/issues/392
+
+**Suggested Action**: Follow up on proposals to implement FIFO scheduling and refactor the Executor design to more easily expose the scheduling logic.
+
+**Notes from 2020-03-19**:
+
+- No comments.
+
+### Make it possible to wait on entities (e.g. Subscriptions) without an Executor
+
+> Currently, it is only possible to use things like Timers and Subscriptions and Services with an executor.
+> It should be possible, however, to either poll these entities or wait on them and then decide which to process as a user.
+>
+> This is most easily accomplished with a WaitSet-like class.
+
+- https://github.com/ros2/rclcpp/issues/520
+
+**Suggested Action**: implement WaitSet class in rclcpp so that this is possible, and make "waitable" entities such that they can be polled, e.g. `Subscription`s should have a user facing `take()` method, which can fail if no data is available.
+
+**Notes from 2020-03-19**:
+
+- No comments.
+
+### Make it possible to use multiple executors per node
+
+> Currently, you cannot use more than one executor per node, this limits your options when it comes to distributing work within a node across threads.
+> You can use a multi-threaded executor, or make your own executor which does this, but it is often convenient to be able to spin part of the node separately from the the rest of the node.
+
+- https://github.com/ros2/rclcpp/issues/519
+
+**Suggested Action**: Make this possible, moving the exclusivity to be between an executor and callback groups rather than nodes.
+
+**Notes from 2020-03-19**:
+
+- No comments.
+
+### Implement a Lock-free Executor
+
+> This would presumably be useful for real-time and safety critical systems where locks and any kind of blocking code is considered undesirable.
+
+- https://github.com/ros2/rclcpp/issues/77
+
+**Suggested Action**: Keep in backlog until someone needs it specifically.
+
+**Notes from 2020-03-19**:
+
+- No comments.
+
+### Add implementation of `spin_some()` to the `MultiThreadedExecutor`
+
+> Currently `spin_some()` is only available in the `SingleThreadedExecutor`.
+
+- https://github.com/ros2/rclcpp/issues/85
+
+**Suggested Action**: Defer.
+
+**Notes from 2020-03-19**:
+
+- No comments.
+
+## Node
+
+### Do argument parsing outside of node constructor
+
+> Things that come from command line arguments should be separately passed into the node's constructor rather than passing in arguments and asking the node to do the parsing.
+
+- https://github.com/ros2/rclcpp/issues/492
+
+**Suggested Action**: Defer until after foxy.
+
+**Notes from 2020-03-23**:
+
+- (dirk) may be related to ROS 1 heritage of argc/argv being passed to node directly
+- (shane) impacts rcl API as well, two parts "global options" as well node specific options
+- (dirk) what is the recommendation to users that want to add arguments programmatically
+  - user should be able to get non-ros argc/argv somehow (seems like you can now)
+- (jacob) the argument in NodeOptions are used for application specific argument via component loading as well
+
+## Timer
+
+### Timer based on ROS Time
+
+> `node->create_wall_timer` does exactly what it says; creates a timer that will call the callback when the wall time expires.  But this is almost never what the user wants, since this won’t work properly in simulation.  Suggestion: deprecate `create_wall_timer`, add a new method called `create_timer` that takes the timer to use as one of the arguments, which defaults to ROS_TIME.
+
+- https://github.com/ros2/rclcpp/blob/96ebf59a6045a535730d98fff25e522807c7aa75/rclcpp/include/rclcpp/node.hpp#L219-L230
+- https://github.com/ros2/rclcpp/issues/465
+
+**Suggested Action**: Promote `rclcpp::create_timer()` which is templated on a clock type, as suggested, but leave `create_wall_timer` as a convenience.
+
+**Notes from 2020-03-19**:
+
+- (shane) may be a `rclcpp::create_timer()` that can be used to create a non-wall timer already
+
+## Publisher
+
+## Subscription
+
+### Callback Signature
+
+> Is there a reason the subscription callback must have a smart pointer argument instead of accepting a const-reference argument?
+
+- https://github.com/ros2/rclcpp/blob/96ebf59a6045a535730d98fff25e522807c7aa75/rclcpp/include/rclcpp/any_subscription_callback.hpp#L44-L52
+- https://github.com/ros2/rclcpp/issues/281
+
+**Suggested Action**: Provide const reference as an option, add documentation as to the implications of one callback signature versus others.
+
+**Notes from 2020-03-19**:
+
+- (dirk) have const reference and document it
+
+## Service Server
+
+### Allow for asynchronous Service Server callbacks
+
+> Currently, the only callback signature for Service Servers takes a request and must return a response.
+> This means that all of the activity of the service server has to happen within that function.
+> This can cause issues, specifically if you want to call another service within the current service server's callback, as it causes deadlock issues trying to synchronously call the second service within a spin callback.
+> More generally, it seems likely that long running service server callbacks may be necessary in the future and requiring them to be synchronous would tie up at least on thread in the spinning executor unnecessarily.
+
+- https://github.com/ros2/rclcpp/issues/491
+
+**Suggested Action**: Defer.
+
+**Notes from 2020-03-23**:
+
+- (dirk) likely new API, so possible to backport
+
+## Service Client
+
+### Callback has SharedFuture rather than const reference to response
+
+> Why does the Client::send_async_request take in a callback that has a SharedFuture argument instead of an argument that is simply a const-reference (or smart pointer) to the service response type? The current API seems to imply that the callback ought to check whether the promise is broken or fulfilled before trying to access it. Is that the case? If so, it should be documented in the header.
+
+- https://github.com/ros2/rclcpp/blob/7c1721a0b390be8242a6b824489d0bc861f6a0ad/rclcpp/include/rclcpp/client.hpp#L134
+
+**Suggested Action**: Update ticket and defer.
+
+**Notes from 2020-03-19**:
+
+- (wjwwood) we wanted the user to handle error cases with the future?
+- (dirk) future allows for single callback (rather than one for response and one for error)
+- (jacob) actions uses a "wrapped result" object
+
+### rclcpp missing synchronous `send_request` and issues with deadlocks
+
+> This has been reported by several users, but there is only an `async_send_request` currently. `rclpy` has a synchronous `send_request` but  it has issues with deadlock, specifically if you call it without spinning in another thread then it will deadlock. Or if you call it from within a spin callback when using a single threaded executor, it will deadlock.
+
+- https://discourse.ros.org/t/synchronous-request-to-service-in-callback-results-in-deadlock/12767
+- https://github.com/ros2/rclcpp/issues/975
+- https://github.com/ros2/demos/blob/948b4f4869298f39cfe99d3ae517ad60a72a8909/demo_nodes_cpp/src/services/add_two_ints_client.cpp#L24-L39
+
+**Suggested Action**: Update issue and defer. Also defer decision on reconciling rclpy's send_request.
+
+**Notes from 2020-03-23**:
+
+- (karsten/shane) async spinner helps in rclpy version, rclcpp could emulate
+- (chris) sees three options:
+  - only async (current case in rclcpp)
+  - have sync version, add lots of docs that spinning needs to happen elsewhere (current case for rclpy)
+  - reentrant spinning
+- (william) you either need async/await from language or ".then" syntax (we have this in async_send_request())
+- (chris) more error checking for recursive spinning
+- (chris) weird that rclcpp and rclpy have different API
+- (shane) thinks it is ok to have different API, but rclpy is not ideal
+
+## Parameters
+
+### Expected vs Unexpected parameters
+
+> Allow node author to define expected parameters and what happens when an unexpected parameter is set.
+
+- https://github.com/ros2/rclcpp/issues/475
+- https://github.com/ros2/rclcpp/tree/check_parameters
+
+**Suggested Action**: Defer as nice to have.
+
+**Notes from 2020-03-23**:
+
+- None.
+
+### Implicitly cast integer values for double parameters
+
+> If we try to pass an integer value to a double parameter from the command line or from a parameters YAML file we get a `rclcpp::ParameterTypeException`.
+> For example, passing a parameter from the command line:
+>
+>     ros2 run foo_package foo_node --ros-args -p foo_arg:=1
+>
+> results in the following error:
+>
+>     terminate called after throwing an instance of 'rclcpp::ParameterTypeException'
+>       what():  expected [double] got [integer]
+>
+> and we can fix it by explicitly making our value a floating point number:
+>
+>     ros2 run foo_package foo_node --ros-args -p foo_arg:=1.0
+>
+> But, it seems reasonable to me that if a user forgets to explicitly provide a floating point value that we should implicitly cast an integer to a float (as is done in many programming languages).
+
+- https://github.com/ros2/rclcpp/issues/979
+
+**Suggested Action**: Continue with issue.
+
+**Notes from 2020-03-23**:
+
+- (shane) says "yes please" :)
+
+### Use `std::variant` instead of custom `ParameterValue` class
+
+> This is only possible if C++17 is available, but it would simplify our code, make our interface more standard, and allow us to use constexpr-if to simply our templated code.
+
+**Suggested Action**: Create an issue for future work.
+
+**Notes from 2020-03-23**:
+
+- (chris) not sure churn is worth
+- (ivan) other places for std::variant, like AnySubscriptionCallback
+
+### Cannot set name or value on `Parameter`/`ParameterValue`
+
+> Both `Parameter` and `ParameterValue` are read-only after construction.
+
+- https://github.com/ros2/rclcpp/issues/238
+
+**Suggested Action**: Update issue, possibly close.
+
+**Notes from 2020-03-23**:
+
+- (chris/william) setting values on temporary (local) objects is not reflected in the node, so misleading
+
+## Parameter Clients
+
+### No timeout option with synchronous parameter client calls
+
+> As an example, SyncParametersClient::set_parameters doesn't take a timeout option. So, if anything goes wrong in the service call (e.g. the server goes down), we will get stuck waiting indefinitely.
+
+- https://github.com/ros2/rclcpp/issues/360
+- https://github.com/ros2/rclcpp/blob/96ebf59a6045a535730d98fff25e522807c7aa75/rclcpp/src/rclcpp/parameter_client.cpp#L453-L468
+
+**Suggested Action**: Update issue, decide if it can be taken for Foxy or not.
+
+**Notes from 2020-03-23**:
+
+- (tfoote) Seems like adding a timeout is a good idea.
+
+### Name of AsyncParametersClient inconsistent
+
+> AsyncParameter**s**Client uses plural, when filename is singular (and ParameterService is singular):
+
+- https://github.com/ros2/rclcpp/blob/7c1721a0b390be8242a6b824489d0bc861f6a0ad/rclcpp/include/rclcpp/parameter_client.hpp#L44
+
+**Suggested Action**: Reconcile class and file name, switch to singular name?
+
+**Notes from on-line, post 2020-03-23 meeting**:
+
+- (tfoote) +1 for homogenizing to singular
+
+### `SyncParametersClient::get_parameters` doesn't allow you to detect error cases
+
+> E.g. https://github.com/ros2/rclcpp/blob/249b7d80d8f677edcda05052f598de84f4c2181c/rclcpp/src/rclcpp/parameter_client.cpp#L246-L257 returns an empty vector if something goes wrong which is also a valid response.
+
+- https://github.com/ros2/rclcpp/issues/200
+- https://github.com/ros2/rclcpp/blob/96ebf59a6045a535730d98fff25e522807c7aa75/rclcpp/src/rclcpp/parameter_client.cpp#L412-L426
+
+**Suggested Action**: Throw an exception to indicate if something went wrong and document other expected conditions of the API.
+
+**Notes from on-line, post 2020-03-23 meeting**:
+
+- (tfoote) An empty list is not a valid response unless you passed in an empty list. The return should have the same length as the request in the same order. Any parameters that are not set should return a ParameterVariant with type PARAMETER_NOT_SET. to indicate that it was polled and determined to not be set. Suggested action improve documentation of the API to clarify a short or incomplete.
+- (jacobperron) I think throwing an exception is also a valid action, making it clear that an error occurred.
+- (wjwwood) Using exceptions to indicate an exceptional case (something went wrong) seems reasonable to me too.
+
+## Clock
+
+### Clock Jump callbacks on System or Steady time?
+
+> Currently time jump callbacks are registered via Clock::create_jump_handler(). Jump handlers are only invoked by TimeSource::set_clock(). This is only called if the clock type is RCL_ROS_TIME and ROS time is active.
+
+- https://github.com/ros2/rclcpp/issues/528
+
+**Suggested Action**: Document that time jumping is only detected with ROS time, consider a warning.
+
+**Notes from on-line, post 2020-03-23 meeting**:
+
+- (tfoote) There should be no jumps in steady time. If there's a big change in system time, it doesn't necessarily mean that time jumped, just that you might have been sleeping for a long time. Most ntp systems adjust the slew rate these days instead of jumping but still that's an external process and I don't know of any APIs to introspect the state of the clock. I'm not sure that we have a way to detect jumps in time for system or steady time. To that end I think that we should be clear that we only provide callbacks when simulation time starts or stops, or simulation time jumps. We should also strongly recommend that operators not actively adjust their system clocks while running ROS nodes.
+- (jacobperron) I agree with Tully, if we don't have a way to detect system time jumps then I think we should just document that this only works with ROS time. In addition to documentation, we could log an info or warning message if the user registers jump callback with steady or system time, but it may be unnecessarily noisy.
+

rclcpp/include/rclcpp/any_executable.hpp

@@ -29,8 +29,6 @@
 
 namespace rclcpp
 {
-namespace executor
-{
 
 struct AnyExecutable
 {
@@ -47,10 +45,15 @@ struct AnyExecutable
   rclcpp::ClientBase::SharedPtr client;
   rclcpp::Waitable::SharedPtr waitable;
   // These are used to keep the scope on the containing items
-  rclcpp::callback_group::CallbackGroup::SharedPtr callback_group;
+  rclcpp::CallbackGroup::SharedPtr callback_group;
   rclcpp::node_interfaces::NodeBaseInterface::SharedPtr node_base;
 };
 
+namespace executor
+{
+
+using AnyExecutable [[deprecated("use rclcpp::AnyExecutable instead")]] = AnyExecutable;
+
 }  // namespace executor
 }  // namespace rclcpp
 

rclcpp/include/rclcpp/any_service_callback.hpp

@@ -24,6 +24,7 @@
 #include "rclcpp/visibility_control.hpp"
 #include "rmw/types.h"
 #include "tracetools/tracetools.h"
+#include "tracetools/utils.hpp"
 
 namespace rclcpp
 {
@@ -98,6 +99,23 @@ public:
     }
     TRACEPOINT(callback_end, (const void *)this);
   }
+
+  void register_callback_for_tracing()
+  {
+#ifndef TRACETOOLS_DISABLED
+    if (shared_ptr_callback_) {
+      TRACEPOINT(
+        rclcpp_callback_register,
+        (const void *)this,
+        get_symbol(shared_ptr_callback_));
+    } else if (shared_ptr_with_request_header_callback_) {
+      TRACEPOINT(
+        rclcpp_callback_register,
+        (const void *)this,
+        get_symbol(shared_ptr_with_request_header_callback_));
+    }
+#endif  // TRACETOOLS_DISABLED
+  }
 };
 
 }  // namespace rclcpp

rclcpp/include/rclcpp/any_subscription_callback.hpp

@@ -25,6 +25,7 @@
 
 #include "rclcpp/allocator/allocator_common.hpp"
 #include "rclcpp/function_traits.hpp"
+#include "rclcpp/message_info.hpp"
 #include "rclcpp/visibility_control.hpp"
 #include "tracetools/tracetools.h"
 #include "tracetools/utils.hpp"
@@ -43,13 +44,13 @@ class AnySubscriptionCallback
 
   using SharedPtrCallback = std::function<void (const std::shared_ptr<MessageT>)>;
   using SharedPtrWithInfoCallback =
-    std::function<void (const std::shared_ptr<MessageT>, const rmw_message_info_t &)>;
+    std::function<void (const std::shared_ptr<MessageT>, const rclcpp::MessageInfo &)>;
   using ConstSharedPtrCallback = std::function<void (const std::shared_ptr<const MessageT>)>;
   using ConstSharedPtrWithInfoCallback =
-    std::function<void (const std::shared_ptr<const MessageT>, const rmw_message_info_t &)>;
+    std::function<void (const std::shared_ptr<const MessageT>, const rclcpp::MessageInfo &)>;
   using UniquePtrCallback = std::function<void (MessageUniquePtr)>;
   using UniquePtrWithInfoCallback =
-    std::function<void (MessageUniquePtr, const rmw_message_info_t &)>;
+    std::function<void (MessageUniquePtr, const rclcpp::MessageInfo &)>;
 
   SharedPtrCallback shared_ptr_callback_;
   SharedPtrWithInfoCallback shared_ptr_with_info_callback_;
@@ -155,7 +156,7 @@ public:
   }
 
   void dispatch(
-    std::shared_ptr<MessageT> message, const rmw_message_info_t & message_info)
+    std::shared_ptr<MessageT> message, const rclcpp::MessageInfo & message_info)
   {
     TRACEPOINT(callback_start, (const void *)this, false);
     if (shared_ptr_callback_) {
@@ -181,7 +182,7 @@ public:
   }
 
   void dispatch_intra_process(
-    ConstMessageSharedPtr message, const rmw_message_info_t & message_info)
+    ConstMessageSharedPtr message, const rclcpp::MessageInfo & message_info)
   {
     TRACEPOINT(callback_start, (const void *)this, true);
     if (const_shared_ptr_callback_) {
@@ -204,7 +205,7 @@ public:
   }
 
   void dispatch_intra_process(
-    MessageUniquePtr message, const rmw_message_info_t & message_info)
+    MessageUniquePtr message, const rclcpp::MessageInfo & message_info)
   {
     TRACEPOINT(callback_start, (const void *)this, true);
     if (shared_ptr_callback_) {
@@ -234,6 +235,7 @@ public:
 
   void register_callback_for_tracing()
   {
+#ifndef TRACETOOLS_DISABLED
     if (shared_ptr_callback_) {
       TRACEPOINT(
         rclcpp_callback_register,
@@ -244,6 +246,16 @@ public:
         rclcpp_callback_register,
         (const void *)this,
         get_symbol(shared_ptr_with_info_callback_));
+    } else if (const_shared_ptr_callback_) {
+      TRACEPOINT(
+        rclcpp_callback_register,
+        (const void *)this,
+        get_symbol(const_shared_ptr_callback_));
+    } else if (const_shared_ptr_with_info_callback_) {
+      TRACEPOINT(
+        rclcpp_callback_register,
+        (const void *)this,
+        get_symbol(const_shared_ptr_with_info_callback_));
     } else if (unique_ptr_callback_) {
       TRACEPOINT(
         rclcpp_callback_register,
@@ -255,6 +267,7 @@ public:
         (const void *)this,
         get_symbol(unique_ptr_with_info_callback_));
     }
+#endif  // TRACETOOLS_DISABLED
   }
 
 private:

rclcpp/include/rclcpp/callback_group.hpp

@@ -40,9 +40,6 @@ class NodeTopics;
 class NodeWaitables;
 }  // namespace node_interfaces
 
-namespace callback_group
-{
-
 enum class CallbackGroupType
 {
   MutuallyExclusive,
@@ -162,6 +159,12 @@ private:
   }
 };
 
+namespace callback_group
+{
+
+using CallbackGroupType [[deprecated("use rclcpp::CallbackGroupType instead")]] = CallbackGroupType;
+using CallbackGroup [[deprecated("use rclcpp::CallbackGroup instead")]] = CallbackGroup;
+
 }  // namespace callback_group
 }  // namespace rclcpp
 

rclcpp/include/rclcpp/client.hpp

@@ -15,6 +15,7 @@
 #ifndef RCLCPP__CLIENT_HPP_
 #define RCLCPP__CLIENT_HPP_
 
+#include <atomic>
 #include <future>
 #include <map>
 #include <memory>
@@ -62,22 +63,64 @@ public:
   RCLCPP_PUBLIC
   virtual ~ClientBase();
 
+  /// Take the next response for this client as a type erased pointer.
+  /**
+   * The type erased pointer allows for this method to be used in a type
+   * agnostic way along with ClientBase::create_response(),
+   * ClientBase::create_request_header(), and ClientBase::handle_response().
+   * The typed version of this can be used if the Service type is known,
+   * \sa Client::take_response().
+   *
+   * \param[out] response_out The type erased pointer to a Service Response into
+   *   which the middleware will copy the response being taken.
+   * \param[out] request_header_out The request header to be filled by the
+   *   middleware when taking, and which can be used to associte the response
+   *   to a specific request.
+   * \returns true if the response was taken, otherwise false.
+   * \throws rclcpp::exceptions::RCLError based exceptions if the underlying
+   *   rcl function fail.
+   */
+  RCLCPP_PUBLIC
+  bool
+  take_type_erased_response(void * response_out, rmw_request_id_t & request_header_out);
+
+  /// Return the name of the service.
+  /** \return The name of the service. */
   RCLCPP_PUBLIC
   const char *
   get_service_name() const;
 
+  /// Return the rcl_client_t client handle in a std::shared_ptr.
+  /**
+   * This handle remains valid after the Client is destroyed.
+   * The actual rcl client is not finalized until it is out of scope everywhere.
+   */
   RCLCPP_PUBLIC
   std::shared_ptr<rcl_client_t>
   get_client_handle();
 
+  /// Return the rcl_client_t client handle in a std::shared_ptr.
+  /**
+   * This handle remains valid after the Client is destroyed.
+   * The actual rcl client is not finalized until it is out of scope everywhere.
+   */
   RCLCPP_PUBLIC
   std::shared_ptr<const rcl_client_t>
   get_client_handle() const;
 
+  /// Return if the service is ready.
+  /**
+   * \return `true` if the service is ready, `false` otherwise
+   */
   RCLCPP_PUBLIC
   bool
   service_is_ready() const;
 
+  /// Wait for a service to be ready.
+  /**
+   * \param timeout maximum time to wait
+   * \return `true` if the service is ready and the timeout is not over, `false` otherwise
+   */
   template<typename RepT = int64_t, typename RatioT = std::milli>
   bool
   wait_for_service(
@@ -93,6 +136,20 @@ public:
   virtual void handle_response(
     std::shared_ptr<rmw_request_id_t> request_header, std::shared_ptr<void> response) = 0;
 
+  /// Exchange the "in use by wait set" state for this client.
+  /**
+   * This is used to ensure this client is not used by multiple
+   * wait sets at the same time.
+   *
+   * \param[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.
+   */
+  RCLCPP_PUBLIC
+  bool
+  exchange_in_use_by_wait_set_state(bool in_use_state);
+
 protected:
   RCLCPP_DISABLE_COPY(ClientBase)
 
@@ -113,6 +170,8 @@ protected:
   std::shared_ptr<rclcpp::Context> context_;
 
   std::shared_ptr<rcl_client_t> client_handle_;
+
+  std::atomic<bool> in_use_by_wait_set_{false};
 };
 
 template<typename ServiceT>
@@ -136,6 +195,17 @@ public:
 
   RCLCPP_SMART_PTR_DEFINITIONS(Client)
 
+  /// Default constructor.
+  /**
+   * The constructor for a Client is almost never called directly.
+   * Instead, clients should be instantiated through the function
+   * rclcpp::create_client().
+   *
+   * \param[in] node_base NodeBaseInterface pointer that is used in part of the setup.
+   * \param[in] node_graph The node graph interface of the corresponding node.
+   * \param[in] service_name Name of the topic to publish to.
+   * \param[in] client_options options for the subscription.
+   */
   Client(
     rclcpp::node_interfaces::NodeBaseInterface * node_base,
     rclcpp::node_interfaces::NodeGraphInterface::SharedPtr node_graph,
@@ -171,12 +241,39 @@ public:
   {
   }
 
+  /// Take the next response for this client.
+  /**
+   * \sa ClientBase::take_type_erased_response().
+   *
+   * \param[out] response_out The reference to a Service Response into
+   *   which the middleware will copy the response being taken.
+   * \param[out] request_header_out The request header to be filled by the
+   *   middleware when taking, and which can be used to associte the response
+   *   to a specific request.
+   * \returns true if the response was taken, otherwise false.
+   * \throws rclcpp::exceptions::RCLError based exceptions if the underlying
+   *   rcl function fail.
+   */
+  bool
+  take_response(typename ServiceT::Response & response_out, rmw_request_id_t & request_header_out)
+  {
+    return this->take_type_erased_response(&response_out, request_header_out);
+  }
+
+  /// Create a shared pointer with the response type
+  /**
+   * \return shared pointer with the response type
+   */
   std::shared_ptr<void>
   create_response() override
   {
     return std::shared_ptr<void>(new typename ServiceT::Response());
   }
 
+  /// Create a shared pointer with a rmw_request_id_t
+  /**
+   * \return shared pointer with a rmw_request_id_t
+   */
   std::shared_ptr<rmw_request_id_t>
   create_request_header() override
   {
@@ -185,6 +282,11 @@ public:
     return std::shared_ptr<rmw_request_id_t>(new rmw_request_id_t);
   }
 
+  /// Handle a server response
+  /**
+    * \param[in] request_header used to check if the secuence number is valid
+    * \param[in] response message with the server response
+   */
   void
   handle_response(
     std::shared_ptr<rmw_request_id_t> request_header,

rclcpp/include/rclcpp/clock.hpp

@@ -16,6 +16,8 @@
 #define RCLCPP__CLOCK_HPP_
 
 #include <functional>
+#include <memory>
+#include <mutex>
 
 #include "rclcpp/macros.hpp"
 #include "rclcpp/time.hpp"
@@ -87,6 +89,7 @@ public:
   bool
   ros_time_is_active();
 
+  /// Return the rcl_clock_t clock handle
   RCLCPP_PUBLIC
   rcl_clock_t *
   get_clock_handle() noexcept;
@@ -95,6 +98,11 @@ public:
   rcl_clock_type_t
   get_clock_type() const noexcept;
 
+  /// Get the clock's mutex
+  RCLCPP_PUBLIC
+  std::mutex &
+  get_clock_mutex() noexcept;
+
   // Add a callback to invoke if the jump threshold is exceeded.
   /**
    * These callback functions must remain valid as long as the
@@ -107,9 +115,9 @@ public:
    *
    * Function is only applicable if the clock_type is `RCL_ROS_TIME`
    *
-   * \param pre_callback. Must be non-throwing
-   * \param post_callback. Must be non-throwing.
-   * \param threshold. Callbacks will be triggered if the time jump is greater
+   * \param pre_callback Must be non-throwing
+   * \param post_callback Must be non-throwing.
+   * \param threshold Callbacks will be triggered if the time jump is greater
    * then the threshold.
    * \throws anything rclcpp::exceptions::throw_from_rcl_error can throw.
    * \throws std::bad_alloc if the allocation of the JumpHandler fails.
@@ -132,10 +140,10 @@ private:
     bool before_jump,
     void * user_data);
 
-  /// Internal storage backed by rcl
-  rcl_clock_t rcl_clock_;
-  friend TimeSource;  /// Allow TimeSource to access the rcl_clock_ datatype.
-  rcl_allocator_t allocator_;
+  /// Private internal storage
+  class Impl;
+
+  std::shared_ptr<Impl> impl_;
 };
 
 }  // namespace rclcpp

rclcpp/include/rclcpp/context.hpp

@@ -44,6 +44,9 @@ public:
   : std::runtime_error("context is already initialized") {}
 };
 
+/// Forward declare WeakContextsWrapper
+class WeakContextsWrapper;
+
 /// Context which encapsulates shared state between nodes and other similar entities.
 /**
  * A context also represents the lifecycle between init and shutdown of rclcpp.
@@ -100,6 +103,9 @@ public:
    * \param[in] argv argument array which may contain arguments intended for ROS
    * \param[in] init_options initialization options for rclcpp and underlying layers
    * \throw ContextAlreadyInitialized if called if init is called more than once
+   * \throws anything rclcpp::exceptions::throw_from_rcl_error can throw.
+   * \throws std::runtime_error if the global logging configure mutex is NULL
+   * \throws exceptions::UnknownROSArgsError if there are unknown ROS arguments
    */
   RCLCPP_PUBLIC
   virtual
@@ -159,7 +165,7 @@ public:
    *
    * \param[in] reason the description of why shutdown happened
    * \return true if shutdown was successful, false if context was already shutdown
-   * \throw various exceptions derived from RCLErrorBase, if rcl_shutdown fails
+   * \throw various exceptions derived from rclcpp::exceptions::RCLError, if rcl_shutdown fails
    */
   RCLCPP_PUBLIC
   virtual
@@ -260,6 +266,7 @@ public:
    * \param[in] wait_set Pointer to the rcl_wait_set_t that will be using the
    *   resulting guard condition.
    * \return Pointer to the guard condition.
+   * \throws anything rclcpp::exceptions::throw_from_rcl_error can throw.
    */
   RCLCPP_PUBLIC
   rcl_guard_condition_t *
@@ -279,6 +286,8 @@ public:
    *
    * \param[in] wait_set Pointer to the rcl_wait_set_t that was using the
    *   resulting guard condition.
+   * \throws anything rclcpp::exceptions::throw_from_rcl_error can throw.
+   * \throws std::runtime_error if a nonexistent wait set is trying to release sigint guard condition.
    */
   RCLCPP_PUBLIC
   void
@@ -338,6 +347,9 @@ private:
   rclcpp::InitOptions init_options_;
   std::string shutdown_reason_;
 
+  // Keep shared ownership of the global logging mutex.
+  std::shared_ptr<std::recursive_mutex> logging_mutex_;
+
   std::unordered_map<std::type_index, std::shared_ptr<void>> sub_contexts_;
   // This mutex is recursive so that the constructor of a sub context may
   // attempt to acquire another sub context.
@@ -355,6 +367,9 @@ private:
   std::mutex interrupt_guard_cond_handles_mutex_;
   /// Guard conditions for interrupting of associated wait sets on interrupt_all_wait_sets().
   std::unordered_map<rcl_wait_set_t *, rcl_guard_condition_t> interrupt_guard_cond_handles_;
+
+  /// Keep shared ownership of global vector of weak contexts
+  std::shared_ptr<WeakContextsWrapper> weak_contexts_;
 };
 
 /// Return a copy of the list of context shared pointers.

rclcpp/include/rclcpp/contexts/default_context.hpp

@@ -22,8 +22,6 @@ namespace rclcpp
 {
 namespace contexts
 {
-namespace default_context
-{
 
 class DefaultContext : public rclcpp::Context
 {
@@ -38,6 +36,21 @@ RCLCPP_PUBLIC
 DefaultContext::SharedPtr
 get_global_default_context();
 
+namespace default_context
+{
+
+using DefaultContext
+[[deprecated("use rclcpp::contexts::DefaultContext instead")]] = DefaultContext;
+
+[[deprecated("use rclcpp::contexts::get_global_default_context() instead")]]
+RCLCPP_PUBLIC
+inline
+DefaultContext::SharedPtr
+get_global_default_context()
+{
+  return rclcpp::contexts::get_global_default_context();
+}
+
 }  // namespace default_context
 }  // namespace contexts
 }  // namespace rclcpp

rclcpp/include/rclcpp/create_client.hpp

@@ -35,7 +35,7 @@ create_client(
   std::shared_ptr<node_interfaces::NodeServicesInterface> node_services,
   const std::string & service_name,
   const rmw_qos_profile_t & qos_profile,
-  rclcpp::callback_group::CallbackGroup::SharedPtr group)
+  rclcpp::CallbackGroup::SharedPtr group)
 {
   rcl_client_options_t options = rcl_client_get_default_options();
   options.qos = qos_profile;

rclcpp/include/rclcpp/create_service.hpp

@@ -37,7 +37,7 @@ create_service(
   const std::string & service_name,
   CallbackT && callback,
   const rmw_qos_profile_t & qos_profile,
-  rclcpp::callback_group::CallbackGroup::SharedPtr group)
+  rclcpp::CallbackGroup::SharedPtr group)
 {
   rclcpp::AnyServiceCallback<ServiceT> any_service_callback;
   any_service_callback.set(std::forward<CallbackT>(callback));

rclcpp/include/rclcpp/create_subscription.hpp

@@ -15,15 +15,27 @@
 #ifndef RCLCPP__CREATE_SUBSCRIPTION_HPP_
 #define RCLCPP__CREATE_SUBSCRIPTION_HPP_
 
+#include <chrono>
+#include <functional>
 #include <memory>
+#include <stdexcept>
 #include <string>
 #include <utility>
 
+#include "rclcpp/detail/resolve_enable_topic_statistics.hpp"
+
+#include "rclcpp/node_interfaces/get_node_timers_interface.hpp"
 #include "rclcpp/node_interfaces/get_node_topics_interface.hpp"
+#include "rclcpp/node_interfaces/node_timers_interface.hpp"
 #include "rclcpp/node_interfaces/node_topics_interface.hpp"
+
+#include "rclcpp/create_publisher.hpp"
+#include "rclcpp/create_timer.hpp"
+#include "rclcpp/qos.hpp"
 #include "rclcpp/subscription_factory.hpp"
 #include "rclcpp/subscription_options.hpp"
-#include "rclcpp/qos.hpp"
+#include "rclcpp/timer.hpp"
+#include "rclcpp/topic_statistics/subscription_topic_statistics.hpp"
 #include "rmw/qos_profiles.h"
 
 namespace rclcpp
@@ -34,6 +46,23 @@ namespace rclcpp
  * The NodeT type only needs to have a method called get_node_topics_interface()
  * which returns a shared_ptr to a NodeTopicsInterface, or be a
  * NodeTopicsInterface pointer itself.
+ *
+ * \tparam MessageT
+ * \tparam CallbackT
+ * \tparam AllocatorT
+ * \tparam CallbackMessageT
+ * \tparam SubscriptionT
+ * \tparam MessageMemoryStrategyT
+ * \tparam NodeT
+ * \param node
+ * \param topic_name
+ * \param qos
+ * \param callback
+ * \param options
+ * \param msg_mem_strat
+ * \return the created subscription
+ * \throws std::invalid_argument if topic statistics is enabled and the publish period is
+ * less than or equal to zero.
  */
 template<
   typename MessageT,
@@ -64,10 +93,59 @@ create_subscription(
   using rclcpp::node_interfaces::get_node_topics_interface;
   auto node_topics = get_node_topics_interface(std::forward<NodeT>(node));
 
+  std::shared_ptr<rclcpp::topic_statistics::SubscriptionTopicStatistics<CallbackMessageT>>
+  subscription_topic_stats = nullptr;
+
+  if (rclcpp::detail::resolve_enable_topic_statistics(
+      options,
+      *node_topics->get_node_base_interface()))
+  {
+    if (options.topic_stats_options.publish_period <= std::chrono::milliseconds(0)) {
+      throw std::invalid_argument(
+              "topic_stats_options.publish_period must be greater than 0, specified value of " +
+              std::to_string(options.topic_stats_options.publish_period.count()) +
+              " ms");
+    }
+
+    std::shared_ptr<Publisher<statistics_msgs::msg::MetricsMessage>> publisher =
+      create_publisher<statistics_msgs::msg::MetricsMessage>(
+      node,
+      options.topic_stats_options.publish_topic,
+      qos);
+
+    subscription_topic_stats = std::make_shared<
+      rclcpp::topic_statistics::SubscriptionTopicStatistics<CallbackMessageT>
+      >(node_topics->get_node_base_interface()->get_name(), publisher);
+
+    std::weak_ptr<
+      rclcpp::topic_statistics::SubscriptionTopicStatistics<CallbackMessageT>
+    > weak_subscription_topic_stats(subscription_topic_stats);
+    auto sub_call_back = [weak_subscription_topic_stats]() {
+        auto subscription_topic_stats = weak_subscription_topic_stats.lock();
+        if (subscription_topic_stats) {
+          subscription_topic_stats->publish_message();
+        }
+      };
+
+    auto node_timer_interface = node_topics->get_node_timers_interface();
+
+    auto timer = create_wall_timer(
+      std::chrono::duration_cast<std::chrono::nanoseconds>(
+        options.topic_stats_options.publish_period),
+      sub_call_back,
+      options.callback_group,
+      node_topics->get_node_base_interface(),
+      node_timer_interface
+    );
+
+    subscription_topic_stats->set_publisher_timer(timer);
+  }
+
   auto factory = rclcpp::create_subscription_factory<MessageT>(
     std::forward<CallbackT>(callback),
     options,
-    msg_mem_strat
+    msg_mem_strat,
+    subscription_topic_stats
   );
 
   auto sub = node_topics->create_subscription(topic_name, factory, qos);

rclcpp/include/rclcpp/create_timer.hpp

@@ -15,6 +15,8 @@
 #ifndef RCLCPP__CREATE_TIMER_HPP_
 #define RCLCPP__CREATE_TIMER_HPP_
 
+#include <chrono>
+#include <exception>
 #include <memory>
 #include <string>
 #include <utility>
@@ -32,12 +34,12 @@ namespace rclcpp
 template<typename CallbackT>
 typename rclcpp::TimerBase::SharedPtr
 create_timer(
-  node_interfaces::NodeBaseInterface * node_base,
-  node_interfaces::NodeTimersInterface * node_timers,
+  std::shared_ptr<node_interfaces::NodeBaseInterface> node_base,
+  std::shared_ptr<node_interfaces::NodeTimersInterface> node_timers,
   rclcpp::Clock::SharedPtr clock,
   rclcpp::Duration period,
   CallbackT && callback,
-  rclcpp::callback_group::CallbackGroup::SharedPtr group = nullptr)
+  rclcpp::CallbackGroup::SharedPtr group = nullptr)
 {
   auto timer = rclcpp::GenericTimer<CallbackT>::make_shared(
     clock,
@@ -57,7 +59,7 @@ create_timer(
   rclcpp::Clock::SharedPtr clock,
   rclcpp::Duration period,
   CallbackT && callback,
-  rclcpp::callback_group::CallbackGroup::SharedPtr group = nullptr)
+  rclcpp::CallbackGroup::SharedPtr group = nullptr)
 {
   return create_timer(
     rclcpp::node_interfaces::get_node_base_interface(node),
@@ -68,6 +70,74 @@ create_timer(
     group);
 }
 
+/// Convenience method to create a timer with node resources.
+/**
+ *
+ * \tparam DurationRepT
+ * \tparam DurationT
+ * \tparam CallbackT
+ * \param period period to execute callback. This duration must be 0 <= period < nanoseconds::max()
+ * \param callback callback to execute via the timer period
+ * \param group
+ * \param node_base
+ * \param node_timers
+ * \return
+ * \throws std::invalid argument if either node_base or node_timers
+ * are null, or period is negative or too large
+ */
+template<typename DurationRepT, typename DurationT, typename CallbackT>
+typename rclcpp::WallTimer<CallbackT>::SharedPtr
+create_wall_timer(
+  std::chrono::duration<DurationRepT, DurationT> period,
+  CallbackT callback,
+  rclcpp::CallbackGroup::SharedPtr group,
+  node_interfaces::NodeBaseInterface * node_base,
+  node_interfaces::NodeTimersInterface * node_timers)
+{
+  if (node_base == nullptr) {
+    throw std::invalid_argument{"input node_base cannot be null"};
+  }
+
+  if (node_timers == nullptr) {
+    throw std::invalid_argument{"input node_timers cannot be null"};
+  }
+
+  if (period < std::chrono::duration<DurationRepT, DurationT>::zero()) {
+    throw std::invalid_argument{"timer period cannot be negative"};
+  }
+
+  // Casting to a double representation might lose precision and allow the check below to succeed
+  // but the actual cast to nanoseconds fail. Using 1 DurationT worth of nanoseconds less than max.
+  constexpr auto maximum_safe_cast_ns =
+    std::chrono::nanoseconds::max() - std::chrono::duration<DurationRepT, DurationT>(1);
+
+  // If period is greater than nanoseconds::max(), the duration_cast to nanoseconds will overflow
+  // a signed integer, which is undefined behavior. Checking whether any std::chrono::duration is
+  // greater than nanoseconds::max() is a difficult general problem. This is a more conservative
+  // version of Howard Hinnant's (the <chrono> guy>) response here:
+  // https://stackoverflow.com/a/44637334/2089061
+  // However, this doesn't solve the issue for all possible duration types of period.
+  // Follow-up issue: https://github.com/ros2/rclcpp/issues/1177
+  constexpr auto ns_max_as_double =
+    std::chrono::duration_cast<std::chrono::duration<double, std::chrono::nanoseconds::period>>(
+    maximum_safe_cast_ns);
+  if (period > ns_max_as_double) {
+    throw std::invalid_argument{
+            "timer period must be less than std::chrono::nanoseconds::max()"};
+  }
+
+  const auto period_ns = std::chrono::duration_cast<std::chrono::nanoseconds>(period);
+  if (period_ns < std::chrono::nanoseconds::zero()) {
+    throw std::runtime_error{
+            "Casting timer period to nanoseconds resulted in integer overflow."};
+  }
+
+  auto timer = rclcpp::WallTimer<CallbackT>::make_shared(
+    period_ns, std::move(callback), node_base->get_context());
+  node_timers->add_timer(timer, group);
+  return timer;
+}
+
 }  // namespace rclcpp
 
 #endif  // RCLCPP__CREATE_TIMER_HPP_

rclcpp/include/rclcpp/detail/mutex_two_priorities.hpp

@@ -0,0 +1,76 @@
+// Copyright 2021 Open Source Robotics Foundation, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef RCLCPP__DETAIL__MUTEX_TWO_PRIORITIES_HPP_
+#define RCLCPP__DETAIL__MUTEX_TWO_PRIORITIES_HPP_
+
+#include <condition_variable>
+#include <mutex>
+
+namespace rclcpp
+{
+namespace detail
+{
+/// \internal A mutex that has two locking mechanism, one with higher priority than the other.
+/**
+ * After the current mutex owner release the lock, a thread that used the high
+ * priority mechanism will have priority over threads that used the low priority mechanism.
+ */
+class MutexTwoPriorities
+{
+public:
+  class HighPriorityLockable
+  {
+public:
+    explicit HighPriorityLockable(MutexTwoPriorities & parent);
+
+    void lock();
+
+    void unlock();
+
+private:
+    MutexTwoPriorities & parent_;
+  };
+
+  class LowPriorityLockable
+  {
+public:
+    explicit LowPriorityLockable(MutexTwoPriorities & parent);
+
+    void lock();
+
+    void unlock();
+
+private:
+    MutexTwoPriorities & parent_;
+  };
+
+  HighPriorityLockable
+  get_high_priority_lockable();
+
+  LowPriorityLockable
+  get_low_priority_lockable();
+
+private:
+  std::condition_variable hp_cv_;
+  std::condition_variable lp_cv_;
+  std::mutex cv_mutex_;
+  size_t hp_waiting_count_{0u};
+  bool data_taken_{false};
+};
+
+}  // namespace detail
+}  // namespace rclcpp
+
+#endif  // RCLCPP__DETAIL__MUTEX_TWO_PRIORITIES_HPP_

rclcpp/include/rclcpp/detail/resolve_enable_topic_statistics.hpp

@@ -0,0 +1,53 @@
+// Copyright 2020 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef RCLCPP__DETAIL__RESOLVE_ENABLE_TOPIC_STATISTICS_HPP_
+#define RCLCPP__DETAIL__RESOLVE_ENABLE_TOPIC_STATISTICS_HPP_
+
+#include <stdexcept>
+
+#include "rclcpp/topic_statistics_state.hpp"
+
+namespace rclcpp
+{
+namespace detail
+{
+
+/// Return whether or not topic statistics is enabled, resolving "NodeDefault" if needed.
+template<typename OptionsT, typename NodeBaseT>
+bool
+resolve_enable_topic_statistics(const OptionsT & options, const NodeBaseT & node_base)
+{
+  bool topic_stats_enabled;
+  switch (options.topic_stats_options.state) {
+    case TopicStatisticsState::Enable:
+      topic_stats_enabled = true;
+      break;
+    case TopicStatisticsState::Disable:
+      topic_stats_enabled = false;
+      break;
+    case TopicStatisticsState::NodeDefault:
+      topic_stats_enabled = node_base.get_enable_topic_statistics_default();
+      break;
+    default:
+      throw std::runtime_error("Unrecognized EnableTopicStatistics value");
+  }
+
+  return topic_stats_enabled;
+}
+
+}  // namespace detail
+}  // namespace rclcpp
+
+#endif  // RCLCPP__DETAIL__RESOLVE_ENABLE_TOPIC_STATISTICS_HPP_

rclcpp/include/rclcpp/detail/utilities.hpp

@@ -0,0 +1,40 @@
+// Copyright 2019 Open Source Robotics Foundation, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef RCLCPP__DETAIL__UTILITIES_HPP_
+#define RCLCPP__DETAIL__UTILITIES_HPP_
+
+#include "rclcpp/detail/utilities.hpp"
+
+#include <string>
+#include <vector>
+
+#include "rcl/allocator.h"
+#include "rcl/arguments.h"
+
+namespace rclcpp
+{
+namespace detail
+{
+
+std::vector<std::string>
+get_unparsed_ros_arguments(
+  int argc, char const * const argv[],
+  rcl_arguments_t * arguments,
+  rcl_allocator_t allocator);
+
+}  // namespace detail
+}  // namespace rclcpp
+
+#endif  // RCLCPP__DETAIL__UTILITIES_HPP_

rclcpp/include/rclcpp/duration.hpp

@@ -26,11 +26,22 @@ namespace rclcpp
 class RCLCPP_PUBLIC Duration
 {
 public:
+  /// Duration constructor.
+  /**
+   * Initializes the time values for seconds and nanoseconds individually.
+   * Large values for nsecs are wrapped automatically with the remainder added to secs.
+   * Both inputs must be integers.
+   * Seconds can be negative.
+   *
+   * \param seconds time in seconds
+   * \param nanoseconds time in nanoseconds
+   */
   Duration(int32_t seconds, uint32_t nanoseconds);
 
-  // This constructor matches any numeric value - ints or floats
+  // This constructor matches any numeric value - ints or floats.
   explicit Duration(rcl_duration_value_t nanoseconds);
 
+  // This constructor matches std::chrono::nanoseconds.
   explicit Duration(std::chrono::nanoseconds nanoseconds);
 
   // This constructor matches any std::chrono value other than nanoseconds
@@ -44,6 +55,10 @@ public:
   // cppcheck-suppress noExplicitConstructor
   Duration(const builtin_interfaces::msg::Duration & duration_msg);  // NOLINT(runtime/explicit)
 
+  /// Time constructor
+  /**
+   * \param duration rcl_duration_t structure to copy.
+   */
   explicit Duration(const rcl_duration_t & duration);
 
   Duration(const Duration & rhs);
@@ -57,11 +72,14 @@ public:
   operator=(const Duration & rhs);
 
   Duration &
-  operator=(const builtin_interfaces::msg::Duration & Duration_msg);
+  operator=(const builtin_interfaces::msg::Duration & duration_msg);
 
   bool
   operator==(const rclcpp::Duration & rhs) const;
 
+  bool
+  operator!=(const rclcpp::Duration & rhs) const;
+
   bool
   operator<(const rclcpp::Duration & rhs) const;
 
@@ -80,6 +98,10 @@ public:
   Duration
   operator-(const rclcpp::Duration & rhs) const;
 
+  /// Get the maximum representable value.
+  /**
+   * \return the maximum representable value
+   */
   static
   Duration
   max();
@@ -87,19 +109,27 @@ public:
   Duration
   operator*(double scale) const;
 
+  /// Get duration in nanosecods
+  /**
+   * \return the duration in nanoseconds as a rcl_duration_value_t.
+   */
   rcl_duration_value_t
   nanoseconds() const;
 
-  /// \return the duration in seconds as a floating point number.
-  /// \warning Depending on sizeof(double) there could be significant precision loss.
-  /// When an exact time is required use nanoseconds() instead.
+  /// Get duration in seconds
+  /**
+   * \warning Depending on sizeof(double) there could be significant precision loss.
+   *   When an exact time is required use nanoseconds() instead.
+   * \return the duration in seconds as a floating point number.
+   */
   double
   seconds() const;
 
-  // Create a duration object from a floating point number representing seconds
+  /// Create a duration object from a floating point number representing seconds
   static Duration
   from_seconds(double seconds);
 
+  /// Convert Duration into a std::chrono::Duration.
   template<class DurationT>
   DurationT
   to_chrono() const
@@ -107,6 +137,7 @@ public:
     return std::chrono::duration_cast<DurationT>(std::chrono::nanoseconds(this->nanoseconds()));
   }
 
+  /// Convert Duration into rmw_time_t.
   rmw_time_t
   to_rmw_time() const;
 

rclcpp/include/rclcpp/event.hpp

@@ -29,17 +29,33 @@ class Event
 public:
   RCLCPP_SMART_PTR_DEFINITIONS_NOT_COPYABLE(Event)
 
+  /// Default construct
+  /**
+   * Set the default value to false
+   */
   RCLCPP_PUBLIC
   Event();
 
+  /// Set the Event state value to true
+  /**
+   * \return The state value before the call.
+   */
   RCLCPP_PUBLIC
   bool
   set();
 
+  /// Get the state value of the Event
+  /**
+   * \return the Event state value
+   */
   RCLCPP_PUBLIC
   bool
   check();
 
+  /// Get the state value of the Event and set to false
+  /**
+   * \return the Event state value
+   */
   RCLCPP_PUBLIC
   bool
   check_and_clear();

rclcpp/include/rclcpp/exceptions.hpp

@@ -15,246 +15,6 @@
 #ifndef RCLCPP__EXCEPTIONS_HPP_
 #define RCLCPP__EXCEPTIONS_HPP_
 
-#include <stdexcept>
-#include <string>
-#include <vector>
-
-#include "rcl/error_handling.h"
-#include "rcl/types.h"
-#include "rclcpp/visibility_control.hpp"
-
-#include "rcpputils/join.hpp"
-
-namespace rclcpp
-{
-namespace exceptions
-{
-
-/// Thrown when a method is trying to use a node, but it is invalid.
-class InvalidNodeError : public std::runtime_error
-{
-public:
-  InvalidNodeError()
-  : std::runtime_error("node is invalid") {}
-};
-
-/// Thrown when a any kind of name (node, namespace, topic, etc.) is invalid.
-class NameValidationError : public std::invalid_argument
-{
-public:
-  NameValidationError(
-    const char * name_type_,
-    const char * name_,
-    const char * error_msg_,
-    size_t invalid_index_)
-  : std::invalid_argument(format_error(name_type_, name_, error_msg_, invalid_index_)),
-    name_type(name_type_), name(name_), error_msg(error_msg_), invalid_index(invalid_index_)
-  {}
-
-  static std::string
-  format_error(
-    const char * name_type,
-    const char * name,
-    const char * error_msg,
-    size_t invalid_index);
-
-  const std::string name_type;
-  const std::string name;
-  const std::string error_msg;
-  const size_t invalid_index;
-};
-
-/// Thrown when a node name is invalid.
-class InvalidNodeNameError : public NameValidationError
-{
-public:
-  InvalidNodeNameError(const char * node_name, const char * error_msg, size_t invalid_index)
-  : NameValidationError("node name", node_name, error_msg, invalid_index)
-  {}
-};
-
-/// Thrown when a node namespace is invalid.
-class InvalidNamespaceError : public NameValidationError
-{
-public:
-  InvalidNamespaceError(const char * namespace_, const char * error_msg, size_t invalid_index)
-  : NameValidationError("namespace", namespace_, error_msg, invalid_index)
-  {}
-};
-
-/// Thrown when a topic name is invalid.
-class InvalidTopicNameError : public NameValidationError
-{
-public:
-  InvalidTopicNameError(const char * namespace_, const char * error_msg, size_t invalid_index)
-  : NameValidationError("topic name", namespace_, error_msg, invalid_index)
-  {}
-};
-
-/// Thrown when a service name is invalid.
-class InvalidServiceNameError : public NameValidationError
-{
-public:
-  InvalidServiceNameError(const char * namespace_, const char * error_msg, size_t invalid_index)
-  : NameValidationError("service name", namespace_, error_msg, invalid_index)
-  {}
-};
-
-/// Throw a C++ std::exception which was created based on an rcl error.
-/**
- * Passing nullptr for reset_error is safe and will avoid calling any function
- * to reset the error.
- *
- * \param ret the return code for the current error state
- * \param prefix string to prefix to the error if applicable (not all errors have custom messages)
- * \param error_state error state to create exception from, if nullptr rcl_get_error_state is used
- * \param reset_error function to be called before throwing which whill clear the error state
- * \throws std::invalid_argument if ret is RCL_RET_OK
- * \throws std::runtime_error if the rcl_get_error_state returns 0
- * \throws RCLErrorBase some child class exception based on ret
- */
-/* *INDENT-OFF* */  // Uncrustify cannot yet understand [[noreturn]] properly
-RCLCPP_PUBLIC
-void
-throw_from_rcl_error [[noreturn]] (
-  rcl_ret_t ret,
-  const std::string & prefix = "",
-  const rcl_error_state_t * error_state = nullptr,
-  void (* reset_error)() = rcl_reset_error);
-/* *INDENT-ON* */
-
-class RCLErrorBase
-{
-public:
-  RCLCPP_PUBLIC
-  RCLErrorBase(rcl_ret_t ret, const rcl_error_state_t * error_state);
-  virtual ~RCLErrorBase() {}
-
-  rcl_ret_t ret;
-  std::string message;
-  std::string file;
-  size_t line;
-  std::string formatted_message;
-};
-
-/// Created when the return code does not match one of the other specialized exceptions.
-class RCLError : public RCLErrorBase, public std::runtime_error
-{
-public:
-  RCLCPP_PUBLIC
-  RCLError(rcl_ret_t ret, const rcl_error_state_t * error_state, const std::string & prefix);
-  RCLCPP_PUBLIC
-  RCLError(const RCLErrorBase & base_exc, const std::string & prefix);
-};
-
-/// Created when the ret is RCL_RET_BAD_ALLOC.
-class RCLBadAlloc : public RCLErrorBase, public std::bad_alloc
-{
-public:
-  RCLCPP_PUBLIC
-  RCLBadAlloc(rcl_ret_t ret, const rcl_error_state_t * error_state);
-  RCLCPP_PUBLIC
-  explicit RCLBadAlloc(const RCLErrorBase & base_exc);
-};
-
-/// Created when the ret is RCL_RET_INVALID_ARGUMENT.
-class RCLInvalidArgument : public RCLErrorBase, public std::invalid_argument
-{
-public:
-  RCLCPP_PUBLIC
-  RCLInvalidArgument(
-    rcl_ret_t ret,
-    const rcl_error_state_t * error_state,
-    const std::string & prefix);
-  RCLCPP_PUBLIC
-  RCLInvalidArgument(const RCLErrorBase & base_exc, const std::string & prefix);
-};
-
-/// Created when the ret is RCL_RET_INVALID_ROS_ARGS.
-class RCLInvalidROSArgsError : public RCLErrorBase, public std::runtime_error
-{
-public:
-  RCLCPP_PUBLIC
-  RCLInvalidROSArgsError(
-    rcl_ret_t ret, const rcl_error_state_t * error_state, const std::string & prefix);
-  RCLCPP_PUBLIC
-  RCLInvalidROSArgsError(const RCLErrorBase & base_exc, const std::string & prefix);
-};
-
-/// Thrown when unparsed ROS specific arguments are found.
-class UnknownROSArgsError : public std::runtime_error
-{
-public:
-  explicit UnknownROSArgsError(std::vector<std::string> && unknown_ros_args_in)
-  : std::runtime_error(
-      "found unknown ROS arguments: '" + rcpputils::join(unknown_ros_args_in, "', '") + "'"),
-    unknown_ros_args(unknown_ros_args_in)
-  {
-  }
-
-  const std::vector<std::string> unknown_ros_args;
-};
-
-/// Thrown when an invalid rclcpp::Event object or SharedPtr is encountered.
-class InvalidEventError : public std::runtime_error
-{
-public:
-  InvalidEventError()
-  : std::runtime_error("event is invalid") {}
-};
-
-/// Thrown when an unregistered rclcpp::Event is encountered where a registered one was expected.
-class EventNotRegisteredError : public std::runtime_error
-{
-public:
-  EventNotRegisteredError()
-  : std::runtime_error("event already registered") {}
-};
-
-/// Thrown if passed parameters are inconsistent or invalid
-class InvalidParametersException : public std::runtime_error
-{
-public:
-  // Inherit constructors from runtime_error.
-  using std::runtime_error::runtime_error;
-};
-
-/// Thrown if passed parameter value is invalid.
-class InvalidParameterValueException : public std::runtime_error
-{
-  // Inherit constructors from runtime_error.
-  using std::runtime_error::runtime_error;
-};
-
-/// Thrown if parameter is already declared.
-class ParameterAlreadyDeclaredException : public std::runtime_error
-{
-  // Inherit constructors from runtime_error.
-  using std::runtime_error::runtime_error;
-};
-
-/// Thrown if parameter is not declared, e.g. either set or get was called without first declaring.
-class ParameterNotDeclaredException : public std::runtime_error
-{
-  // Inherit constructors from runtime_error.
-  using std::runtime_error::runtime_error;
-};
-
-/// Thrown if parameter is immutable and therefore cannot be undeclared.
-class ParameterImmutableException : public std::runtime_error
-{
-  // Inherit constructors from runtime_error.
-  using std::runtime_error::runtime_error;
-};
-
-/// Thrown if parameter is modified while in a set callback.
-class ParameterModifiedInCallbackException : public std::runtime_error
-{
-  // Inherit constructors from runtime_error.
-  using std::runtime_error::runtime_error;
-};
-
-}  // namespace exceptions
-}  // namespace rclcpp
+#include "rclcpp/exceptions/exceptions.hpp"
 
 #endif  // RCLCPP__EXCEPTIONS_HPP_

rclcpp/include/rclcpp/exceptions/exceptions.hpp

@@ -0,0 +1,288 @@
+// Copyright 2016 Open Source Robotics Foundation, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef RCLCPP__EXCEPTIONS__EXCEPTIONS_HPP_
+#define RCLCPP__EXCEPTIONS__EXCEPTIONS_HPP_
+
+#include <stdexcept>
+#include <string>
+#include <vector>
+
+#include "rcl/error_handling.h"
+#include "rcl/types.h"
+#include "rclcpp/visibility_control.hpp"
+
+#include "rcpputils/join.hpp"
+
+namespace rclcpp
+{
+namespace exceptions
+{
+
+/// Thrown when a method is trying to use a node, but it is invalid.
+class InvalidNodeError : public std::runtime_error
+{
+public:
+  InvalidNodeError()
+  : std::runtime_error("node is invalid") {}
+};
+
+/// Thrown when a any kind of name (node, namespace, topic, etc.) is invalid.
+class NameValidationError : public std::invalid_argument
+{
+public:
+  NameValidationError(
+    const char * name_type_,
+    const char * name_,
+    const char * error_msg_,
+    size_t invalid_index_)
+  : std::invalid_argument(format_error(name_type_, name_, error_msg_, invalid_index_)),
+    name_type(name_type_), name(name_), error_msg(error_msg_), invalid_index(invalid_index_)
+  {}
+
+  static std::string
+  format_error(
+    const char * name_type,
+    const char * name,
+    const char * error_msg,
+    size_t invalid_index);
+
+  const std::string name_type;
+  const std::string name;
+  const std::string error_msg;
+  const size_t invalid_index;
+};
+
+/// Thrown when a node name is invalid.
+class InvalidNodeNameError : public NameValidationError
+{
+public:
+  InvalidNodeNameError(const char * node_name, const char * error_msg, size_t invalid_index)
+  : NameValidationError("node name", node_name, error_msg, invalid_index)
+  {}
+};
+
+/// Thrown when a node namespace is invalid.
+class InvalidNamespaceError : public NameValidationError
+{
+public:
+  InvalidNamespaceError(const char * namespace_, const char * error_msg, size_t invalid_index)
+  : NameValidationError("namespace", namespace_, error_msg, invalid_index)
+  {}
+};
+
+/// Thrown when a topic name is invalid.
+class InvalidTopicNameError : public NameValidationError
+{
+public:
+  InvalidTopicNameError(const char * namespace_, const char * error_msg, size_t invalid_index)
+  : NameValidationError("topic name", namespace_, error_msg, invalid_index)
+  {}
+};
+
+/// Thrown when a service name is invalid.
+class InvalidServiceNameError : public NameValidationError
+{
+public:
+  InvalidServiceNameError(const char * namespace_, const char * error_msg, size_t invalid_index)
+  : NameValidationError("service name", namespace_, error_msg, invalid_index)
+  {}
+};
+
+class UnimplementedError : public std::runtime_error
+{
+public:
+  UnimplementedError()
+  : std::runtime_error("This code is unimplemented.") {}
+  explicit UnimplementedError(const std::string & msg)
+  : std::runtime_error(msg) {}
+};
+
+/// Throw a C++ std::exception which was created based on an rcl error.
+/**
+ * Passing nullptr for reset_error is safe and will avoid calling any function
+ * to reset the error.
+ *
+ * \param ret the return code for the current error state
+ * \param prefix string to prefix to the error if applicable (not all errors have custom messages)
+ * \param error_state error state to create exception from, if nullptr rcl_get_error_state is used
+ * \param reset_error function to be called before throwing which whill clear the error state
+ * \throws std::invalid_argument if ret is RCL_RET_OK
+ * \throws std::runtime_error if the rcl_get_error_state returns 0
+ * \throws RCLErrorBase some child class exception based on ret
+ */
+/* *INDENT-OFF* */  // Uncrustify cannot yet understand [[noreturn]] properly
+RCLCPP_PUBLIC
+void
+throw_from_rcl_error [[noreturn]] (
+  rcl_ret_t ret,
+  const std::string & prefix = "",
+  const rcl_error_state_t * error_state = nullptr,
+  void (* reset_error)() = rcl_reset_error);
+/* *INDENT-ON* */
+
+class RCLErrorBase
+{
+public:
+  RCLCPP_PUBLIC
+  RCLErrorBase(rcl_ret_t ret, const rcl_error_state_t * error_state);
+  virtual ~RCLErrorBase() {}
+
+  rcl_ret_t ret;
+  std::string message;
+  std::string file;
+  size_t line;
+  std::string formatted_message;
+};
+
+/// Created when the return code does not match one of the other specialized exceptions.
+class RCLError : public RCLErrorBase, public std::runtime_error
+{
+public:
+  RCLCPP_PUBLIC
+  RCLError(rcl_ret_t ret, const rcl_error_state_t * error_state, const std::string & prefix);
+  RCLCPP_PUBLIC
+  RCLError(const RCLErrorBase & base_exc, const std::string & prefix);
+};
+
+/// Created when the ret is RCL_RET_BAD_ALLOC.
+class RCLBadAlloc : public RCLErrorBase, public std::bad_alloc
+{
+public:
+  RCLCPP_PUBLIC
+  RCLBadAlloc(rcl_ret_t ret, const rcl_error_state_t * error_state);
+  RCLCPP_PUBLIC
+  explicit RCLBadAlloc(const RCLErrorBase & base_exc);
+};
+
+/// Created when the ret is RCL_RET_INVALID_ARGUMENT.
+class RCLInvalidArgument : public RCLErrorBase, public std::invalid_argument
+{
+public:
+  RCLCPP_PUBLIC
+  RCLInvalidArgument(
+    rcl_ret_t ret,
+    const rcl_error_state_t * error_state,
+    const std::string & prefix);
+  RCLCPP_PUBLIC
+  RCLInvalidArgument(const RCLErrorBase & base_exc, const std::string & prefix);
+};
+
+/// Created when the ret is RCL_RET_INVALID_ROS_ARGS.
+class RCLInvalidROSArgsError : public RCLErrorBase, public std::runtime_error
+{
+public:
+  RCLCPP_PUBLIC
+  RCLInvalidROSArgsError(
+    rcl_ret_t ret, const rcl_error_state_t * error_state, const std::string & prefix);
+  RCLCPP_PUBLIC
+  RCLInvalidROSArgsError(const RCLErrorBase & base_exc, const std::string & prefix);
+};
+
+/// Thrown when unparsed ROS specific arguments are found.
+class UnknownROSArgsError : public std::runtime_error
+{
+public:
+  explicit UnknownROSArgsError(std::vector<std::string> && unknown_ros_args_in)
+  : std::runtime_error(
+      "found unknown ROS arguments: '" + rcpputils::join(unknown_ros_args_in, "', '") + "'"),
+    unknown_ros_args(unknown_ros_args_in)
+  {
+  }
+
+  const std::vector<std::string> unknown_ros_args;
+};
+
+/// Thrown when an invalid rclcpp::Event object or SharedPtr is encountered.
+class InvalidEventError : public std::runtime_error
+{
+public:
+  InvalidEventError()
+  : std::runtime_error("event is invalid") {}
+};
+
+/// Thrown when an unregistered rclcpp::Event is encountered where a registered one was expected.
+class EventNotRegisteredError : public std::runtime_error
+{
+public:
+  EventNotRegisteredError()
+  : std::runtime_error("event already registered") {}
+};
+
+/// Thrown if passed parameters are inconsistent or invalid
+class InvalidParametersException : public std::runtime_error
+{
+public:
+  // Inherit constructors from runtime_error.
+  using std::runtime_error::runtime_error;
+};
+
+/// Thrown if passed parameter value is invalid.
+class InvalidParameterValueException : public std::runtime_error
+{
+  // Inherit constructors from runtime_error.
+  using std::runtime_error::runtime_error;
+};
+
+/// Thrown if requested parameter type is invalid.
+/**
+ * Essentially the same as rclcpp::ParameterTypeException, but with parameter
+ * name in the error message.
+ */
+class InvalidParameterTypeException : public std::runtime_error
+{
+public:
+  /// Construct an instance.
+  /**
+   * \param[in] name the name of the parameter.
+   * \param[in] message custom exception message.
+   */
+  RCLCPP_PUBLIC
+  InvalidParameterTypeException(const std::string & name, const std::string message)
+  : std::runtime_error("parameter '" + name + "' has invalid type: " + message)
+  {}
+};
+
+/// Thrown if parameter is already declared.
+class ParameterAlreadyDeclaredException : public std::runtime_error
+{
+  // Inherit constructors from runtime_error.
+  using std::runtime_error::runtime_error;
+};
+
+/// Thrown if parameter is not declared, e.g. either set or get was called without first declaring.
+class ParameterNotDeclaredException : public std::runtime_error
+{
+  // Inherit constructors from runtime_error.
+  using std::runtime_error::runtime_error;
+};
+
+/// Thrown if parameter is immutable and therefore cannot be undeclared.
+class ParameterImmutableException : public std::runtime_error
+{
+  // Inherit constructors from runtime_error.
+  using std::runtime_error::runtime_error;
+};
+
+/// Thrown if parameter is modified while in a set callback.
+class ParameterModifiedInCallbackException : public std::runtime_error
+{
+  // Inherit constructors from runtime_error.
+  using std::runtime_error::runtime_error;
+};
+
+}  // namespace exceptions
+}  // namespace rclcpp
+
+#endif  // RCLCPP__EXCEPTIONS__EXCEPTIONS_HPP_

rclcpp/include/rclcpp/executor.hpp

@@ -30,11 +30,14 @@
 #include "rcl/wait.h"
 
 #include "rclcpp/contexts/default_context.hpp"
+#include "rclcpp/executor_options.hpp"
+#include "rclcpp/future_return_code.hpp"
 #include "rclcpp/memory_strategies.hpp"
 #include "rclcpp/memory_strategy.hpp"
 #include "rclcpp/node_interfaces/node_base_interface.hpp"
 #include "rclcpp/utilities.hpp"
 #include "rclcpp/visibility_control.hpp"
+#include "rclcpp/scope_exit.hpp"
 
 namespace rclcpp
 {
@@ -42,48 +45,6 @@ namespace rclcpp
 // Forward declaration is used in convenience method signature.
 class Node;
 
-namespace executor
-{
-
-/// Return codes to be used with spin_until_future_complete.
-/**
- * SUCCESS: The future is complete and can be accessed with "get" without blocking.
- *          This does not indicate that the operation succeeded; "get" may still throw an exception.
- * INTERRUPTED: The future is not complete, spinning was interrupted by Ctrl-C or another error.
- * TIMEOUT: Spinning timed out.
- */
-enum class FutureReturnCode {SUCCESS, INTERRUPTED, TIMEOUT};
-
-RCLCPP_PUBLIC
-std::ostream &
-operator<<(std::ostream & os, const FutureReturnCode & future_return_code);
-
-RCLCPP_PUBLIC
-std::string
-to_string(const FutureReturnCode & future_return_code);
-
-///
-/**
- * Options to be passed to the executor constructor.
- */
-struct ExecutorArgs
-{
-  ExecutorArgs()
-  : memory_strategy(memory_strategies::create_default_strategy()),
-    context(rclcpp::contexts::default_context::get_global_default_context()),
-    max_conditions(0)
-  {}
-
-  memory_strategy::MemoryStrategy::SharedPtr memory_strategy;
-  std::shared_ptr<rclcpp::Context> context;
-  size_t max_conditions;
-};
-
-static inline ExecutorArgs create_default_executor_arguments()
-{
-  return ExecutorArgs();
-}
-
 /// Coordinate the order and timing of available communication tasks.
 /**
  * Executor provides spin functions (including spin_node_once and spin_some).
@@ -100,9 +61,11 @@ public:
   RCLCPP_SMART_PTR_DEFINITIONS_NOT_COPYABLE(Executor)
 
   /// Default constructor.
-  // \param[in] ms The memory strategy to be used with this executor.
+  /**
+   * \param[in] options Options used to configure the executor.
+   */
   RCLCPP_PUBLIC
-  explicit Executor(const ExecutorArgs & args = ExecutorArgs());
+  explicit Executor(const rclcpp::ExecutorOptions & options = rclcpp::ExecutorOptions());
 
   /// Default destructor.
   RCLCPP_PUBLIC
@@ -126,6 +89,9 @@ public:
   add_node(rclcpp::node_interfaces::NodeBaseInterface::SharedPtr node_ptr, bool notify = true);
 
   /// Convenience function which takes Node and forwards NodeBaseInterface.
+  /**
+   * \see rclcpp::Executor::add_node
+   */
   RCLCPP_PUBLIC
   virtual void
   add_node(std::shared_ptr<rclcpp::Node> node_ptr, bool notify = true);
@@ -142,6 +108,9 @@ public:
   remove_node(rclcpp::node_interfaces::NodeBaseInterface::SharedPtr node_ptr, bool notify = true);
 
   /// Convenience function which takes Node and forwards NodeBaseInterface.
+  /**
+   * \see rclcpp::Executor::remove_node
+   */
   RCLCPP_PUBLIC
   virtual void
   remove_node(std::shared_ptr<rclcpp::Node> node_ptr, bool notify = true);
@@ -223,7 +192,7 @@ public:
   template<typename ResponseT, typename TimeRepT = int64_t, typename TimeT = std::milli>
   FutureReturnCode
   spin_until_future_complete(
-    std::shared_future<ResponseT> & future,
+    const std::shared_future<ResponseT> & future,
     std::chrono::duration<TimeRepT, TimeT> timeout = std::chrono::duration<TimeRepT, TimeT>(-1))
   {
     // TODO(wjwwood): does not work recursively; can't call spin_node_until_future_complete
@@ -244,9 +213,14 @@ public:
     }
     std::chrono::nanoseconds timeout_left = timeout_ns;
 
-    while (rclcpp::ok(this->context_)) {
+    if (spinning.exchange(true)) {
+      throw std::runtime_error("spin_until_future_complete() called while already spinning");
+    }
+    RCLCPP_SCOPE_EXIT(this->spinning.store(false); );
+    while (rclcpp::ok(this->context_) && spinning.load()) {
       // Do one item of work.
-      spin_once(timeout_left);
+      spin_once_impl(timeout_left);
+
       // Check if the future is set, return SUCCESS if it is.
       status = future.wait_for(std::chrono::seconds(0));
       if (status == std::future_status::ready) {
@@ -270,7 +244,10 @@ public:
   }
 
   /// Cancel any running spin* function, causing it to return.
-  /* This function can be called asynchonously from any thread. */
+  /**
+   * This function can be called asynchonously from any thread.
+   * \throws std::runtime_error if there is an issue triggering the guard condition
+   */
   RCLCPP_PUBLIC
   void
   cancel();
@@ -280,6 +257,7 @@ public:
    * Switching the memory strategy while the executor is spinning in another threading could have
    * unintended consequences.
    * \param[in] memory_strategy Shared pointer to the memory strategy to set.
+   * \throws std::runtime_error if memory_strategy is null
    */
   RCLCPP_PUBLIC
   void
@@ -293,8 +271,10 @@ protected:
     std::chrono::nanoseconds timeout);
 
   /// Find the next available executable and do the work associated with it.
-  /** \param[in] any_exec Union structure that can hold any executable type (timer, subscription,
+  /**
+   * \param[in] any_exec Union structure that can hold any executable type (timer, subscription,
    * service, client).
+   * \throws std::runtime_error if there is an issue triggering the guard condition
    */
   RCLCPP_PUBLIC
   void
@@ -317,16 +297,19 @@ protected:
   static void
   execute_client(rclcpp::ClientBase::SharedPtr client);
 
+  /**
+   * \throws std::runtime_error if the wait set can be cleared
+   */
   RCLCPP_PUBLIC
   void
   wait_for_work(std::chrono::nanoseconds timeout = std::chrono::nanoseconds(-1));
 
   RCLCPP_PUBLIC
   rclcpp::node_interfaces::NodeBaseInterface::SharedPtr
-  get_node_by_group(rclcpp::callback_group::CallbackGroup::SharedPtr group);
+  get_node_by_group(rclcpp::CallbackGroup::SharedPtr group);
 
   RCLCPP_PUBLIC
-  rclcpp::callback_group::CallbackGroup::SharedPtr
+  rclcpp::CallbackGroup::SharedPtr
   get_group_by_timer(rclcpp::TimerBase::SharedPtr timer);
 
   RCLCPP_PUBLIC
@@ -357,13 +340,22 @@ protected:
   /// The context associated with this executor.
   std::shared_ptr<rclcpp::Context> context_;
 
-private:
   RCLCPP_DISABLE_COPY(Executor)
 
   std::list<rclcpp::node_interfaces::NodeBaseInterface::WeakPtr> weak_nodes_;
   std::list<const rcl_guard_condition_t *> guard_conditions_;
+
+private:
+  RCLCPP_PUBLIC
+  void
+  spin_once_impl(std::chrono::nanoseconds timeout);
 };
 
+namespace executor
+{
+
+using Executor [[deprecated("use rclcpp::Executor instead")]] = rclcpp::Executor;
+
 }  // namespace executor
 }  // namespace rclcpp
 

rclcpp/include/rclcpp/executor_options.hpp

@@ -0,0 +1,57 @@
+// Copyright 2014-2020 Open Source Robotics Foundation, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef RCLCPP__EXECUTOR_OPTIONS_HPP_
+#define RCLCPP__EXECUTOR_OPTIONS_HPP_
+
+#include "rclcpp/context.hpp"
+#include "rclcpp/contexts/default_context.hpp"
+#include "rclcpp/memory_strategies.hpp"
+#include "rclcpp/memory_strategy.hpp"
+#include "rclcpp/visibility_control.hpp"
+
+namespace rclcpp
+{
+
+/// Options to be passed to the executor constructor.
+struct ExecutorOptions
+{
+  ExecutorOptions()
+  : memory_strategy(rclcpp::memory_strategies::create_default_strategy()),
+    context(rclcpp::contexts::get_global_default_context()),
+    max_conditions(0)
+  {}
+
+  rclcpp::memory_strategy::MemoryStrategy::SharedPtr memory_strategy;
+  rclcpp::Context::SharedPtr context;
+  size_t max_conditions;
+};
+
+namespace executor
+{
+
+using ExecutorArgs [[deprecated("use rclcpp::ExecutorOptions instead")]] = ExecutorOptions;
+
+[[deprecated("use rclcpp::ExecutorOptions() instead")]]
+inline
+rclcpp::ExecutorOptions
+create_default_executor_arguments()
+{
+  return rclcpp::ExecutorOptions();
+}
+
+}  // namespace executor
+}  // namespace rclcpp
+
+#endif  // RCLCPP__EXECUTOR_OPTIONS_HPP_

rclcpp/include/rclcpp/executors.hpp

@@ -20,6 +20,7 @@
 
 #include "rclcpp/executors/multi_threaded_executor.hpp"
 #include "rclcpp/executors/single_threaded_executor.hpp"
+#include "rclcpp/executors/static_single_threaded_executor.hpp"
 #include "rclcpp/node.hpp"
 #include "rclcpp/utilities.hpp"
 #include "rclcpp/visibility_control.hpp"
@@ -66,11 +67,11 @@ using rclcpp::executors::SingleThreadedExecutor;
  * \return The return code, one of `SUCCESS`, `INTERRUPTED`, or `TIMEOUT`.
  */
 template<typename ResponseT, typename TimeRepT = int64_t, typename TimeT = std::milli>
-rclcpp::executor::FutureReturnCode
+rclcpp::FutureReturnCode
 spin_node_until_future_complete(
-  rclcpp::executor::Executor & executor,
+  rclcpp::Executor & executor,
   rclcpp::node_interfaces::NodeBaseInterface::SharedPtr node_ptr,
-  std::shared_future<ResponseT> & future,
+  const std::shared_future<ResponseT> & future,
   std::chrono::duration<TimeRepT, TimeT> timeout = std::chrono::duration<TimeRepT, TimeT>(-1))
 {
   // TODO(wjwwood): does not work recursively; can't call spin_node_until_future_complete
@@ -83,11 +84,11 @@ spin_node_until_future_complete(
 
 template<typename NodeT = rclcpp::Node, typename ResponseT, typename TimeRepT = int64_t,
   typename TimeT = std::milli>
-rclcpp::executor::FutureReturnCode
+rclcpp::FutureReturnCode
 spin_node_until_future_complete(
-  rclcpp::executor::Executor & executor,
+  rclcpp::Executor & executor,
   std::shared_ptr<NodeT> node_ptr,
-  std::shared_future<ResponseT> & future,
+  const std::shared_future<ResponseT> & future,
   std::chrono::duration<TimeRepT, TimeT> timeout = std::chrono::duration<TimeRepT, TimeT>(-1))
 {
   return rclcpp::executors::spin_node_until_future_complete(
@@ -100,10 +101,10 @@ spin_node_until_future_complete(
 }  // namespace executors
 
 template<typename FutureT, typename TimeRepT = int64_t, typename TimeT = std::milli>
-rclcpp::executor::FutureReturnCode
+rclcpp::FutureReturnCode
 spin_until_future_complete(
   rclcpp::node_interfaces::NodeBaseInterface::SharedPtr node_ptr,
-  std::shared_future<FutureT> & future,
+  const std::shared_future<FutureT> & future,
   std::chrono::duration<TimeRepT, TimeT> timeout = std::chrono::duration<TimeRepT, TimeT>(-1))
 {
   rclcpp::executors::SingleThreadedExecutor executor;
@@ -112,10 +113,10 @@ spin_until_future_complete(
 
 template<typename NodeT = rclcpp::Node, typename FutureT, typename TimeRepT = int64_t,
   typename TimeT = std::milli>
-rclcpp::executor::FutureReturnCode
+rclcpp::FutureReturnCode
 spin_until_future_complete(
   std::shared_ptr<NodeT> node_ptr,
-  std::shared_future<FutureT> & future,
+  const std::shared_future<FutureT> & future,
   std::chrono::duration<TimeRepT, TimeT> timeout = std::chrono::duration<TimeRepT, TimeT>(-1))
 {
   return rclcpp::spin_until_future_complete(node_ptr->get_node_base_interface(), future, timeout);

rclcpp/include/rclcpp/executors/multi_threaded_executor.hpp

@@ -22,6 +22,7 @@
 #include <thread>
 #include <unordered_map>
 
+#include "rclcpp/detail/mutex_two_priorities.hpp"
 #include "rclcpp/executor.hpp"
 #include "rclcpp/macros.hpp"
 #include "rclcpp/memory_strategies.hpp"
@@ -32,7 +33,7 @@ namespace rclcpp
 namespace executors
 {
 
-class MultiThreadedExecutor : public executor::Executor
+class MultiThreadedExecutor : public rclcpp::Executor
 {
 public:
   RCLCPP_SMART_PTR_DEFINITIONS(MultiThreadedExecutor)
@@ -45,14 +46,15 @@ public:
    * This is useful for reproducing some bugs related to taking work more than
    * once.
    *
-   * \param args common arguments for all executors
+   * \param options common options for all executors
    * \param number_of_threads number of threads to have in the thread pool,
    *   the default 0 will use the number of cpu cores found instead
    * \param yield_before_execute if true std::this_thread::yield() is called
+   * \param timeout maximum time to wait
    */
   RCLCPP_PUBLIC
   MultiThreadedExecutor(
-    const executor::ExecutorArgs & args = executor::ExecutorArgs(),
+    const rclcpp::ExecutorOptions & options = rclcpp::ExecutorOptions(),
     size_t number_of_threads = 0,
     bool yield_before_execute = false,
     std::chrono::nanoseconds timeout = std::chrono::nanoseconds(-1));
@@ -60,9 +62,13 @@ public:
   RCLCPP_PUBLIC
   virtual ~MultiThreadedExecutor();
 
+  /**
+   * \sa rclcpp::Executor:spin() for more details
+   * \throws std::runtime_error when spin() called while already spinning
+   */
   RCLCPP_PUBLIC
   void
-  spin();
+  spin() override;
 
   RCLCPP_PUBLIC
   size_t
@@ -76,12 +82,17 @@ protected:
 private:
   RCLCPP_DISABLE_COPY(MultiThreadedExecutor)
 
-  std::mutex wait_mutex_;
+  std::mutex wait_mutex_;  // Unused. Leave it for ABI compatibility.
   size_t number_of_threads_;
   bool yield_before_execute_;
   std::chrono::nanoseconds next_exec_timeout_;
 
   std::set<TimerBase::SharedPtr> scheduled_timers_;
+  static std::unordered_map<MultiThreadedExecutor *,
+    std::shared_ptr<detail::MutexTwoPriorities>> wait_mutex_set_;
+  static std::mutex shared_wait_mutex_;
+  // These variables are declared as static variables for ABI-compatibiliity.
+  // And they mimic member variables needed to backport from master.
 };
 
 }  // namespace executors

rclcpp/include/rclcpp/executors/single_threaded_executor.hpp

@@ -35,28 +35,35 @@ namespace rclcpp
 namespace executors
 {
 
-/// Single-threaded executor implementation
-// This is the default executor created by rclcpp::spin.
-class SingleThreadedExecutor : public executor::Executor
+/// Single-threaded executor implementation.
+/**
+ * This is the default executor created by rclcpp::spin.
+ */
+class SingleThreadedExecutor : public rclcpp::Executor
 {
 public:
   RCLCPP_SMART_PTR_DEFINITIONS(SingleThreadedExecutor)
 
   /// Default constructor. See the default constructor for Executor.
   RCLCPP_PUBLIC
-  SingleThreadedExecutor(
-    const executor::ExecutorArgs & args = executor::ExecutorArgs());
+  explicit SingleThreadedExecutor(
+    const rclcpp::ExecutorOptions & options = rclcpp::ExecutorOptions());
 
-  /// Default destrcutor.
+  /// Default destructor.
   RCLCPP_PUBLIC
   virtual ~SingleThreadedExecutor();
 
   /// Single-threaded implementation of spin.
-  // This function will block until work comes in, execute it, and keep blocking.
-  // It will only be interrupt by a CTRL-C (managed by the global signal handler).
+  /**
+   * This function will block until work comes in, execute it, and then repeat
+   * the process until canceled.
+   * It may be interrupt by a call to rclcpp::Executor::cancel() or by ctrl-c
+   * if the associated context is configured to shutdown on SIGINT.
+   * \throws std::runtime_error when spin() called while already spinning
+   */
   RCLCPP_PUBLIC
   void
-  spin();
+  spin() override;
 
 private:
   RCLCPP_DISABLE_COPY(SingleThreadedExecutor)

rclcpp/include/rclcpp/executors/static_executor_entities_collector.hpp

@@ -0,0 +1,244 @@
+// Copyright 2020 Open Source Robotics Foundation, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef RCLCPP__EXECUTORS__STATIC_EXECUTOR_ENTITIES_COLLECTOR_HPP_
+#define RCLCPP__EXECUTORS__STATIC_EXECUTOR_ENTITIES_COLLECTOR_HPP_
+
+#include <chrono>
+#include <list>
+#include <memory>
+
+#include "rcl/guard_condition.h"
+#include "rcl/wait.h"
+
+#include "rclcpp/experimental/executable_list.hpp"
+#include "rclcpp/macros.hpp"
+#include "rclcpp/memory_strategy.hpp"
+#include "rclcpp/visibility_control.hpp"
+#include "rclcpp/waitable.hpp"
+
+namespace rclcpp
+{
+namespace executors
+{
+
+class StaticExecutorEntitiesCollector final
+  : public rclcpp::Waitable,
+  public std::enable_shared_from_this<StaticExecutorEntitiesCollector>
+{
+public:
+  RCLCPP_SMART_PTR_DEFINITIONS(StaticExecutorEntitiesCollector)
+
+  // Constructor
+  RCLCPP_PUBLIC
+  StaticExecutorEntitiesCollector() = default;
+
+  // Destructor
+  RCLCPP_PUBLIC
+  ~StaticExecutorEntitiesCollector();
+
+  /// Initialize StaticExecutorEntitiesCollector
+  /**
+   * \param p_wait_set A reference to the wait set to be used in the executor
+   * \param memory_strategy Shared pointer to the memory strategy to set.
+   * \param executor_guard_condition executor's guard condition
+   * \throws std::runtime_error if memory strategy is null
+   */
+  RCLCPP_PUBLIC
+  void
+  init(
+    rcl_wait_set_t * p_wait_set,
+    rclcpp::memory_strategy::MemoryStrategy::SharedPtr & memory_strategy,
+    rcl_guard_condition_t * executor_guard_condition);
+
+  /// Finalize StaticExecutorEntitiesCollector to clear resources
+  RCLCPP_PUBLIC
+  void
+  fini();
+
+  RCLCPP_PUBLIC
+  void
+  execute() override;
+
+  RCLCPP_PUBLIC
+  void
+  fill_memory_strategy();
+
+  RCLCPP_PUBLIC
+  void
+  fill_executable_list();
+
+  /// Function to reallocate space for entities in the wait set.
+  /**
+   * \throws std::runtime_error if wait set couldn't be cleared or resized.
+   */
+  RCLCPP_PUBLIC
+  void
+  prepare_wait_set();
+
+  /// Function to add_handles_to_wait_set and wait for work and
+  /**
+   * block until the wait set is ready or until the timeout has been exceeded.
+   * \throws std::runtime_error if wait set couldn't be cleared or filled.
+   * \throws any rcl errors from rcl_wait, \sa rclcpp::exceptions::throw_from_rcl_error()
+   */
+  RCLCPP_PUBLIC
+  void
+  refresh_wait_set(std::chrono::nanoseconds timeout = std::chrono::nanoseconds(-1));
+
+  /**
+   * \throws std::runtime_error if it couldn't add guard condition to wait set
+   */
+  RCLCPP_PUBLIC
+  bool
+  add_to_wait_set(rcl_wait_set_t * wait_set) override;
+
+  RCLCPP_PUBLIC
+  size_t
+  get_number_of_ready_guard_conditions() override;
+
+  /**
+   * \sa rclcpp::Executor::add_node()
+   * \throw std::runtime_error if node was already added
+   */
+  RCLCPP_PUBLIC
+  void
+  add_node(
+    rclcpp::node_interfaces::NodeBaseInterface::SharedPtr node_ptr);
+
+  /**
+   * \sa rclcpp::Executor::remove_node()
+   * \throw std::runtime_error if no guard condition is associated with node.
+   */
+  RCLCPP_PUBLIC
+  bool
+  remove_node(
+    rclcpp::node_interfaces::NodeBaseInterface::SharedPtr node_ptr);
+
+  /// Complete all available queued work without blocking.
+  /**
+   * This function checks if after the guard condition was triggered
+   * (or a spurious wakeup happened) we are really ready to execute
+   * i.e. re-collect entities
+   */
+  RCLCPP_PUBLIC
+  bool
+  is_ready(rcl_wait_set_t * wait_set) override;
+
+  /// Return number of timers
+  /**
+   * \return number of timers
+   */
+  RCLCPP_PUBLIC
+  size_t
+  get_number_of_timers() {return exec_list_.number_of_timers;}
+
+  /// Return number of subscriptions
+  /**
+   * \return number of subscriptions
+   */
+  RCLCPP_PUBLIC
+  size_t
+  get_number_of_subscriptions() {return exec_list_.number_of_subscriptions;}
+
+  /// Return number of services
+  /**
+   * \return number of services
+   */
+  RCLCPP_PUBLIC
+  size_t
+  get_number_of_services() {return exec_list_.number_of_services;}
+
+  /// Return number of clients
+  /**
+   * \return number of clients
+   */
+  RCLCPP_PUBLIC
+  size_t
+  get_number_of_clients() {return exec_list_.number_of_clients;}
+
+  /// Return number of waitables
+  /**
+   * \return number of waitables
+   */
+  RCLCPP_PUBLIC
+  size_t
+  get_number_of_waitables() {return exec_list_.number_of_waitables;}
+
+  /** Return a SubscritionBase Sharedptr by index.
+   * \param[in] i The index of the SubscritionBase
+   * \return a SubscritionBase shared pointer
+   * \throws std::out_of_range if the argument is higher than the size of the structrue.
+   */
+  RCLCPP_PUBLIC
+  rclcpp::SubscriptionBase::SharedPtr
+  get_subscription(size_t i) {return exec_list_.subscription[i];}
+
+  /** Return a TimerBase Sharedptr by index.
+   * \param[in] i The index of the TimerBase
+   * \return a TimerBase shared pointer
+   * \throws std::out_of_range if the argument is higher than the size.
+   */
+  RCLCPP_PUBLIC
+  rclcpp::TimerBase::SharedPtr
+  get_timer(size_t i) {return exec_list_.timer[i];}
+
+  /** Return a ServiceBase Sharedptr by index.
+   * \param[in] i The index of the ServiceBase
+   * \return a ServiceBase shared pointer
+   * \throws std::out_of_range if the argument is higher than the size.
+   */
+  RCLCPP_PUBLIC
+  rclcpp::ServiceBase::SharedPtr
+  get_service(size_t i) {return exec_list_.service[i];}
+
+  /** Return a ClientBase Sharedptr by index
+   * \param[in] i The index of the ClientBase
+   * \return a ClientBase shared pointer
+   * \throws std::out_of_range if the argument is higher than the size.
+   */
+  RCLCPP_PUBLIC
+  rclcpp::ClientBase::SharedPtr
+  get_client(size_t i) {return exec_list_.client[i];}
+
+  /** Return a Waitable Sharedptr by index
+   * \param[in] i The index of the Waitable
+   * \return a Waitable shared pointer
+   * \throws std::out_of_range if the argument is higher than the size.
+   */
+  RCLCPP_PUBLIC
+  rclcpp::Waitable::SharedPtr
+  get_waitable(size_t i) {return exec_list_.waitable[i];}
+
+private:
+  /// Nodes guard conditions which trigger this waitable
+  std::list<const rcl_guard_condition_t *> guard_conditions_;
+
+  /// Memory strategy: an interface for handling user-defined memory allocation strategies.
+  rclcpp::memory_strategy::MemoryStrategy::SharedPtr memory_strategy_;
+
+  /// List of weak nodes registered in the static executor
+  std::list<rclcpp::node_interfaces::NodeBaseInterface::WeakPtr> weak_nodes_;
+
+  /// Wait set for managing entities that the rmw layer waits on.
+  rcl_wait_set_t * p_wait_set_ = nullptr;
+
+  /// Executable list: timers, subscribers, clients, services and waitables
+  rclcpp::experimental::ExecutableList exec_list_;
+};
+
+}  // namespace executors
+}  // namespace rclcpp
+
+#endif  // RCLCPP__EXECUTORS__STATIC_EXECUTOR_ENTITIES_COLLECTOR_HPP_

rclcpp/include/rclcpp/executors/static_single_threaded_executor.hpp

@@ -0,0 +1,213 @@
+// Copyright 2019 Nobleo Technology
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef RCLCPP__EXECUTORS__STATIC_SINGLE_THREADED_EXECUTOR_HPP_
+#define RCLCPP__EXECUTORS__STATIC_SINGLE_THREADED_EXECUTOR_HPP_
+
+#include <cassert>
+#include <cstdlib>
+#include <memory>
+#include <vector>
+#include <string>
+
+#include "rmw/rmw.h"
+
+#include "rclcpp/executor.hpp"
+#include "rclcpp/executors/static_executor_entities_collector.hpp"
+#include "rclcpp/experimental/executable_list.hpp"
+#include "rclcpp/macros.hpp"
+#include "rclcpp/memory_strategies.hpp"
+#include "rclcpp/node.hpp"
+#include "rclcpp/rate.hpp"
+#include "rclcpp/utilities.hpp"
+#include "rclcpp/visibility_control.hpp"
+
+namespace rclcpp
+{
+namespace executors
+{
+
+/// Static executor implementation
+/**
+ * This executor is a static version of the original single threaded executor.
+ * It's static because it doesn't reconstruct the executable list for every iteration.
+ * All nodes, callbackgroups, timers, subscriptions etc. are created before
+ * spin() is called, and modified only when an entity is added/removed to/from a node.
+ *
+ * To run this executor instead of SingleThreadedExecutor replace:
+ * rclcpp::executors::SingleThreadedExecutor exec;
+ * by
+ * rclcpp::executors::StaticSingleThreadedExecutor exec;
+ * in your source code and spin node(s) in the following way:
+ * exec.add_node(node);
+ * exec.spin();
+ * exec.remove_node(node);
+ */
+class StaticSingleThreadedExecutor : public rclcpp::Executor
+{
+public:
+  RCLCPP_SMART_PTR_DEFINITIONS(StaticSingleThreadedExecutor)
+
+  /// Default constructor. See the default constructor for Executor.
+  RCLCPP_PUBLIC
+  explicit StaticSingleThreadedExecutor(
+    const rclcpp::ExecutorOptions & options = rclcpp::ExecutorOptions());
+
+  /// Default destrcutor.
+  RCLCPP_PUBLIC
+  virtual ~StaticSingleThreadedExecutor();
+
+  /// Static executor implementation of spin.
+  /**
+   * This function will block until work comes in, execute it, and keep blocking.
+   * It will only be interrupted by a CTRL-C (managed by the global signal handler).
+   * \throws std::runtime_error when spin() called while already spinning
+   */
+  RCLCPP_PUBLIC
+  void
+  spin() override;
+
+  /// Add a node to the executor.
+  /**
+   * An executor can have zero or more nodes which provide work during `spin` functions.
+   * \param[in] node_ptr Shared pointer to the node to be added.
+   * \param[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.
+   * \throw std::runtime_error if node was already added or if rcl_trigger_guard_condition
+   * return an error
+   */
+  RCLCPP_PUBLIC
+  void
+  add_node(
+    rclcpp::node_interfaces::NodeBaseInterface::SharedPtr node_ptr,
+    bool notify = true) override;
+
+  /// Convenience function which takes Node and forwards NodeBaseInterface.
+  /**
+   * \throw std::runtime_error if node was already added or if rcl_trigger_guard_condition
+   * returns an error
+   */
+  RCLCPP_PUBLIC
+  void
+  add_node(std::shared_ptr<rclcpp::Node> node_ptr, bool notify = true) override;
+
+  /// Remove a node from the executor.
+  /**
+   * \param[in] node_ptr Shared pointer to the node to remove.
+   * \param[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.
+   * \throw std::runtime_error if rcl_trigger_guard_condition returns an error
+   */
+  RCLCPP_PUBLIC
+  void
+  remove_node(
+    rclcpp::node_interfaces::NodeBaseInterface::SharedPtr node_ptr,
+    bool notify = true) override;
+
+  /// Convenience function which takes Node and forwards NodeBaseInterface.
+  /**
+   * \throw std::runtime_error if rcl_trigger_guard_condition returns an error
+   */
+  RCLCPP_PUBLIC
+  void
+  remove_node(std::shared_ptr<rclcpp::Node> node_ptr, bool notify = true) override;
+
+  /// Spin (blocking) until the future is complete, it times out waiting, or rclcpp is interrupted.
+  /**
+   * \param[in] future The future to wait on. If this function returns SUCCESS, the future can be
+   *   accessed without blocking (though it may still throw an exception).
+   * \param[in] timeout Optional timeout parameter, which gets passed to
+   *    Executor::execute_ready_executables.
+   *   `-1` is block forever, `0` is non-blocking.
+   *   If the time spent inside the blocking loop exceeds this timeout, return a TIMEOUT return
+   *   code.
+   * \return The return code, one of `SUCCESS`, `INTERRUPTED`, or `TIMEOUT`.
+   *
+   *  Example usage:
+   *  rclcpp::executors::StaticSingleThreadedExecutor exec;
+   *  // ... other part of code like creating node
+   *  // define future
+   *  exec.add_node(node);
+   *  exec.spin_until_future_complete(future);
+   */
+  template<typename ResponseT, typename TimeRepT = int64_t, typename TimeT = std::milli>
+  rclcpp::FutureReturnCode
+  spin_until_future_complete(
+    std::shared_future<ResponseT> & future,
+    std::chrono::duration<TimeRepT, TimeT> timeout = std::chrono::duration<TimeRepT, TimeT>(-1))
+  {
+    std::future_status status = future.wait_for(std::chrono::seconds(0));
+    if (status == std::future_status::ready) {
+      return rclcpp::FutureReturnCode::SUCCESS;
+    }
+
+    auto end_time = std::chrono::steady_clock::now();
+    std::chrono::nanoseconds timeout_ns = std::chrono::duration_cast<std::chrono::nanoseconds>(
+      timeout);
+    if (timeout_ns > std::chrono::nanoseconds::zero()) {
+      end_time += timeout_ns;
+    }
+    std::chrono::nanoseconds timeout_left = timeout_ns;
+
+    entities_collector_->init(&wait_set_, memory_strategy_, &interrupt_guard_condition_);
+    RCLCPP_SCOPE_EXIT(entities_collector_->fini());
+
+    while (rclcpp::ok(this->context_)) {
+      // Do one set of work.
+      entities_collector_->refresh_wait_set(timeout_left);
+      execute_ready_executables();
+      // Check if the future is set, return SUCCESS if it is.
+      status = future.wait_for(std::chrono::seconds(0));
+      if (status == std::future_status::ready) {
+        return rclcpp::FutureReturnCode::SUCCESS;
+      }
+      // If the original timeout is < 0, then this is blocking, never TIMEOUT.
+      if (timeout_ns < std::chrono::nanoseconds::zero()) {
+        continue;
+      }
+      // Otherwise check if we still have time to wait, return TIMEOUT if not.
+      auto now = std::chrono::steady_clock::now();
+      if (now >= end_time) {
+        return rclcpp::FutureReturnCode::TIMEOUT;
+      }
+      // Subtract the elapsed time from the original timeout.
+      timeout_left = std::chrono::duration_cast<std::chrono::nanoseconds>(end_time - now);
+    }
+
+    // The future did not complete before ok() returned false, return INTERRUPTED.
+    return rclcpp::FutureReturnCode::INTERRUPTED;
+  }
+
+protected:
+  /// Check which executables in ExecutableList struct are ready from wait_set and execute them.
+  /**
+   * \param[in] exec_list Structure that can hold subscriptionbases, timerbases, etc
+   * \param[in] timeout Optional timeout parameter.
+   */
+  RCLCPP_PUBLIC
+  void
+  execute_ready_executables();
+
+private:
+  RCLCPP_DISABLE_COPY(StaticSingleThreadedExecutor)
+
+  StaticExecutorEntitiesCollector::SharedPtr entities_collector_;
+};
+
+}  // namespace executors
+}  // namespace rclcpp
+
+#endif  // RCLCPP__EXECUTORS__STATIC_SINGLE_THREADED_EXECUTOR_HPP_

rclcpp/include/rclcpp/expand_topic_or_service_name.hpp

@@ -49,6 +49,8 @@ namespace rclcpp
  * \throws InvalidServiceNameError if name is invalid and is_service is true
  * \throws std::bad_alloc if memory cannot be allocated
  * \throws RCLError if an unexpect error occurs
+ * \throws std::runtime_error if the topic name is unexpectedly valid or,
+ *    if the rcl name is invalid or if the rcl namespace is invalid
  */
 RCLCPP_PUBLIC
 std::string

rclcpp/include/rclcpp/experimental/executable_list.hpp

@@ -0,0 +1,92 @@
+// Copyright 2019 Nobleo Technology
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef RCLCPP__EXPERIMENTAL__EXECUTABLE_LIST_HPP_
+#define RCLCPP__EXPERIMENTAL__EXECUTABLE_LIST_HPP_
+
+#include <memory>
+#include <vector>
+
+#include "rclcpp/client.hpp"
+#include "rclcpp/service.hpp"
+#include "rclcpp/subscription_base.hpp"
+#include "rclcpp/timer.hpp"
+#include "rclcpp/visibility_control.hpp"
+#include "rclcpp/waitable.hpp"
+
+namespace rclcpp
+{
+namespace experimental
+{
+
+/// This class contains subscriptionbase, timerbase, etc. which can be used to run callbacks.
+class ExecutableList final
+{
+public:
+  RCLCPP_PUBLIC
+  ExecutableList();
+
+  RCLCPP_PUBLIC
+  ~ExecutableList();
+
+  RCLCPP_PUBLIC
+  void
+  clear();
+
+  RCLCPP_PUBLIC
+  void
+  add_subscription(rclcpp::SubscriptionBase::SharedPtr subscription);
+
+  RCLCPP_PUBLIC
+  void
+  add_timer(rclcpp::TimerBase::SharedPtr timer);
+
+  RCLCPP_PUBLIC
+  void
+  add_service(rclcpp::ServiceBase::SharedPtr service);
+
+  RCLCPP_PUBLIC
+  void
+  add_client(rclcpp::ClientBase::SharedPtr client);
+
+  RCLCPP_PUBLIC
+  void
+  add_waitable(rclcpp::Waitable::SharedPtr waitable);
+
+  // Vector containing the SubscriptionBase of all the subscriptions added to the executor.
+  std::vector<rclcpp::SubscriptionBase::SharedPtr> subscription;
+  // Contains the count of added subscriptions
+  size_t number_of_subscriptions;
+  // Vector containing the TimerBase of all the timers added to the executor.
+  std::vector<rclcpp::TimerBase::SharedPtr> timer;
+  // Contains the count of added timers
+  size_t number_of_timers;
+  // Vector containing the ServiceBase of all the services added to the executor.
+  std::vector<rclcpp::ServiceBase::SharedPtr> service;
+  // Contains the count of added services
+  size_t number_of_services;
+  // Vector containing the ClientBase of all the clients added to the executor.
+  std::vector<rclcpp::ClientBase::SharedPtr> client;
+  // Contains the count of added clients
+  size_t number_of_clients;
+  // Vector containing all the waitables added to the executor.
+  std::vector<rclcpp::Waitable::SharedPtr> waitable;
+  // Contains the count of added waitables
+  size_t number_of_waitables;
+};
+
+}  // namespace experimental
+}  // namespace rclcpp
+
+#endif  // RCLCPP__EXPERIMENTAL__EXECUTABLE_LIST_HPP_

rclcpp/include/rclcpp/experimental/intra_process_manager.hpp

@@ -202,7 +202,8 @@ public:
       // None of the buffers require ownership, so we promote the pointer
       std::shared_ptr<MessageT> msg = std::move(message);
 
-      this->template add_shared_msg_to_buffers<MessageT>(msg, sub_ids.take_shared_subscriptions);
+      this->template add_shared_msg_to_buffers<MessageT, Alloc, Deleter>(
+        msg, sub_ids.take_shared_subscriptions);
     } else if (!sub_ids.take_ownership_subscriptions.empty() && // NOLINT
       sub_ids.take_shared_subscriptions.size() <= 1)
     {
@@ -227,12 +228,10 @@ public:
       // for the buffers that do not require ownership
       auto shared_msg = std::allocate_shared<MessageT, MessageAllocatorT>(*allocator, *message);
 
-      this->template add_shared_msg_to_buffers<MessageT>(shared_msg,
-        sub_ids.take_shared_subscriptions);
+      this->template add_shared_msg_to_buffers<MessageT, Alloc, Deleter>(
+        shared_msg, sub_ids.take_shared_subscriptions);
       this->template add_owned_msg_to_buffers<MessageT, Alloc, Deleter>(
-        std::move(message),
-        sub_ids.take_ownership_subscriptions,
-        allocator);
+        std::move(message), sub_ids.take_ownership_subscriptions, allocator);
     }
   }
 
@@ -265,8 +264,8 @@ public:
       // If there are no owning, just convert to shared.
       std::shared_ptr<MessageT> shared_msg = std::move(message);
       if (!sub_ids.take_shared_subscriptions.empty()) {
-        this->template add_shared_msg_to_buffers<MessageT>(shared_msg,
-          sub_ids.take_shared_subscriptions);
+        this->template add_shared_msg_to_buffers<MessageT, Alloc, Deleter>(
+          shared_msg, sub_ids.take_shared_subscriptions);
       }
       return shared_msg;
     } else {
@@ -275,7 +274,7 @@ public:
       auto shared_msg = std::allocate_shared<MessageT, MessageAllocatorT>(*allocator, *message);
 
       if (!sub_ids.take_shared_subscriptions.empty()) {
-        this->template add_shared_msg_to_buffers<MessageT>(
+        this->template add_shared_msg_to_buffers<MessageT, Alloc, Deleter>(
           shared_msg,
           sub_ids.take_shared_subscriptions);
       }
@@ -352,7 +351,10 @@ private:
   bool
   can_communicate(PublisherInfo pub_info, SubscriptionInfo sub_info) const;
 
-  template<typename MessageT>
+  template<
+    typename MessageT,
+    typename Alloc,
+    typename Deleter>
   void
   add_shared_msg_to_buffers(
     std::shared_ptr<const MessageT> message,
@@ -365,10 +367,16 @@ private:
       }
       auto subscription_base = subscription_it->second.subscription;
 
-      auto subscription = std::static_pointer_cast<
-        rclcpp::experimental::SubscriptionIntraProcess<MessageT>
+      auto subscription = std::dynamic_pointer_cast<
+        rclcpp::experimental::SubscriptionIntraProcess<MessageT, Alloc, Deleter>
         >(subscription_base);
-
+      if (nullptr == subscription) {
+        throw std::runtime_error(
+                "failed to dynamic cast SubscriptionIntraProcessBase to "
+                "SubscriptionIntraProcess<MessageT, Alloc, Deleter>, which "
+                "can happen when the publisher and subscription use different "
+                "allocator types, which is not supported");
+      }
       subscription->provide_intra_process_message(message);
     }
   }
@@ -393,9 +401,16 @@ private:
       }
       auto subscription_base = subscription_it->second.subscription;
 
-      auto subscription = std::static_pointer_cast<
-        rclcpp::experimental::SubscriptionIntraProcess<MessageT>
+      auto subscription = std::dynamic_pointer_cast<
+        rclcpp::experimental::SubscriptionIntraProcess<MessageT, Alloc, Deleter>
         >(subscription_base);
+      if (nullptr == subscription) {
+        throw std::runtime_error(
+                "failed to dynamic cast SubscriptionIntraProcessBase to "
+                "SubscriptionIntraProcess<MessageT, Alloc, Deleter>, which "
+                "can happen when the publisher and subscription use different "
+                "allocator types, which is not supported");
+      }
 
       if (std::next(it) == subscription_ids.end()) {
         // If this is the last subscription, give up ownership

rclcpp/include/rclcpp/experimental/subscription_intra_process.hpp

@@ -97,7 +97,9 @@ public:
     // The callback object gets copied, so if registration is done too early/before this point
     // (e.g. in `AnySubscriptionCallback::set()`), its address won't match any address used later
     // in subsequent tracepoints.
+#ifndef TRACETOOLS_DISABLED
     any_callback_.register_callback_for_tracing();
+#endif
   }
 
   bool
@@ -152,6 +154,7 @@ private:
   execute_impl()
   {
     rmw_message_info_t msg_info;
+    msg_info.publisher_gid = {0, {0}};
     msg_info.from_intra_process = true;
 
     if (any_callback_.use_take_shared_method()) {

rclcpp/include/rclcpp/function_traits.hpp

@@ -88,8 +88,7 @@ struct function_traits<std::_Bind<ReturnTypeT(ClassT::*(FArgs ...))(Args ...)>>
 struct function_traits<std::_Bind<std::_Mem_fn<ReturnTypeT (ClassT::*)(Args ...)>(FArgs ...)>>
 #elif defined _MSC_VER  // MS Visual Studio
 struct function_traits<
-  std::_Binder<std::_Unforced, ReturnTypeT(__cdecl ClassT::*)(Args ...), FArgs ...>
->
+  std::_Binder<std::_Unforced, ReturnTypeT (ClassT::*)(Args ...), FArgs ...>>
 #else
 #error "Unsupported C++ compiler / standard library"
 #endif
@@ -106,8 +105,7 @@ struct function_traits<std::_Bind<ReturnTypeT(ClassT::*(FArgs ...))(Args ...) co
 struct function_traits<std::_Bind<std::_Mem_fn<ReturnTypeT (ClassT::*)(Args ...) const>(FArgs ...)>>
 #elif defined _MSC_VER  // MS Visual Studio
 struct function_traits<
-  std::_Binder<std::_Unforced, ReturnTypeT(__cdecl ClassT::*)(Args ...) const, FArgs ...>
->
+  std::_Binder<std::_Unforced, ReturnTypeT (ClassT::*)(Args ...) const, FArgs ...>>
 #else
 #error "Unsupported C++ compiler / standard library"
 #endif
@@ -121,7 +119,7 @@ struct function_traits<std::__bind<ReturnTypeT( &)(Args ...), FArgs ...>>
 #elif defined __GLIBCXX__  // glibc++ (GNU C++)
 struct function_traits<std::_Bind<ReturnTypeT(*(FArgs ...))(Args ...)>>
 #elif defined _MSC_VER  // MS Visual Studio
-struct function_traits<std::_Binder<std::_Unforced, ReturnTypeT(__cdecl &)(Args ...), FArgs ...>>
+struct function_traits<std::_Binder<std::_Unforced, ReturnTypeT( &)(Args ...), FArgs ...>>
 #else
 #error "Unsupported C++ compiler / standard library"
 #endif

rclcpp/include/rclcpp/future_return_code.hpp

@@ -0,0 +1,61 @@
+// Copyright 2014 Open Source Robotics Foundation, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef RCLCPP__FUTURE_RETURN_CODE_HPP_
+#define RCLCPP__FUTURE_RETURN_CODE_HPP_
+
+#include <iostream>
+#include <string>
+
+#include "rclcpp/visibility_control.hpp"
+
+namespace rclcpp
+{
+
+/// Return codes to be used with spin_until_future_complete.
+/**
+ * SUCCESS: The future is complete and can be accessed with "get" without blocking.
+ *          This does not indicate that the operation succeeded; "get" may still throw an exception.
+ * INTERRUPTED: The future is not complete, spinning was interrupted by Ctrl-C or another error.
+ * TIMEOUT: Spinning timed out.
+ */
+enum class FutureReturnCode {SUCCESS, INTERRUPTED, TIMEOUT};
+
+/// Stream operator for FutureReturnCode.
+RCLCPP_PUBLIC
+std::ostream &
+operator<<(std::ostream & os, const FutureReturnCode & future_return_code);
+
+/// String conversion function for FutureReturnCode.
+RCLCPP_PUBLIC
+std::string
+to_string(const FutureReturnCode & future_return_code);
+
+namespace executor
+{
+
+using FutureReturnCode [[deprecated("use rclcpp::FutureReturnCode instead")]] = FutureReturnCode;
+
+[[deprecated("use rclcpp::to_string(const rclcpp::FutureReturnCode &) instead")]]
+inline
+std::string
+to_string(const rclcpp::FutureReturnCode & future_return_code)
+{
+  return rclcpp::to_string(future_return_code);
+}
+
+}  // namespace executor
+}  // namespace rclcpp
+
+#endif  // RCLCPP__FUTURE_RETURN_CODE_HPP_

rclcpp/include/rclcpp/graph_listener.hpp

@@ -73,6 +73,8 @@ public:
    * This function is thread-safe.
    *
    * \throws GraphListenerShutdownError if the GraphListener is shutdown
+   * \throws std::runtime if the parent context was destroyed
+   * \throws anything rclcpp::exceptions::throw_from_rcl_error can throw.
    */
   RCLCPP_PUBLIC
   virtual
@@ -165,7 +167,7 @@ private:
   void
   __shutdown(bool);
 
-  rclcpp::Context::SharedPtr parent_context_;
+  rclcpp::Context::WeakPtr parent_context_;
 
   std::thread listener_thread_;
   bool is_started_;
@@ -177,7 +179,6 @@ private:
   std::vector<rclcpp::node_interfaces::NodeGraphInterface *> node_graph_interfaces_;
 
   rcl_guard_condition_t interrupt_guard_condition_ = rcl_get_zero_initialized_guard_condition();
-  std::shared_ptr<rcl_context_t> interrupt_guard_condition_context_;
   rcl_guard_condition_t * shutdown_guard_condition_;
   rcl_wait_set_t wait_set_ = rcl_get_zero_initialized_wait_set();
 };

rclcpp/include/rclcpp/guard_condition.hpp

@@ -0,0 +1,100 @@
+// Copyright 2020 Open Source Robotics Foundation, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef RCLCPP__GUARD_CONDITION_HPP_
+#define RCLCPP__GUARD_CONDITION_HPP_
+
+#include <atomic>
+
+#include "rcl/guard_condition.h"
+
+#include "rclcpp/context.hpp"
+#include "rclcpp/contexts/default_context.hpp"
+#include "rclcpp/macros.hpp"
+#include "rclcpp/visibility_control.hpp"
+
+namespace rclcpp
+{
+
+/// A condition that can be waited on in a single wait set and asynchronously triggered.
+class GuardCondition
+{
+public:
+  RCLCPP_SMART_PTR_DEFINITIONS_NOT_COPYABLE(GuardCondition)
+
+  // TODO(wjwwood): support custom allocator, maybe restrict to polymorphic allocator
+  /// Construct the guard condition, optionally specifying which Context to use.
+  /**
+   * \param[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.
+   * \throws std::invalid_argument if the context is nullptr.
+   * \throws rclcpp::exceptions::RCLError based exceptions when underlying
+   *   rcl functions fail.
+   */
+  RCLCPP_PUBLIC
+  explicit GuardCondition(
+    rclcpp::Context::SharedPtr context =
+    rclcpp::contexts::get_global_default_context());
+
+  RCLCPP_PUBLIC
+  virtual
+  ~GuardCondition();
+
+  /// Return the context used when creating this guard condition.
+  RCLCPP_PUBLIC
+  rclcpp::Context::SharedPtr
+  get_context() const;
+
+  /// Return the underlying rcl guard condition structure.
+  RCLCPP_PUBLIC
+  const rcl_guard_condition_t &
+  get_rcl_guard_condition() const;
+
+  /// 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.
+   *
+   * \throws rclcpp::exceptions::RCLError based exceptions when underlying
+   *   rcl functions fail.
+   */
+  RCLCPP_PUBLIC
+  void
+  trigger();
+
+  /// 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.
+   *
+   * \param[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.
+   */
+  RCLCPP_PUBLIC
+  bool
+  exchange_in_use_by_wait_set_state(bool in_use_state);
+
+protected:
+  rclcpp::Context::SharedPtr context_;
+  rcl_guard_condition_t rcl_guard_condition_;
+  std::atomic<bool> in_use_by_wait_set_{false};
+};
+
+}  // namespace rclcpp
+
+#endif  // RCLCPP__GUARD_CONDITION_HPP_

rclcpp/include/rclcpp/init_options.hpp

@@ -30,11 +30,21 @@ public:
   /// If true, the context will be shutdown on SIGINT by the signal handler (if it was installed).
   bool shutdown_on_sigint = true;
 
-  /// Constructor which allows you to specify the allocator used within the init options.
+  /// Constructor
+  /**
+   * It allows you to specify the allocator used within the init options.
+   * \param[in] allocator used allocate memory within the init options
+   * \throws anything rclcpp::exceptions::throw_from_rcl_error can throw.
+   */
   RCLCPP_PUBLIC
   explicit InitOptions(rcl_allocator_t allocator = rcl_get_default_allocator());
 
   /// Constructor which is initialized by an existing init_options.
+  /**
+   * Initialized by an existing init_options.
+   * \param[in] init_options rcl_init_options_t to initialized
+   * \throws anything rclcpp::exceptions::throw_from_rcl_error can throw.
+   */
   RCLCPP_PUBLIC
   explicit InitOptions(const rcl_init_options_t & init_options);
 
@@ -42,6 +52,16 @@ public:
   RCLCPP_PUBLIC
   InitOptions(const InitOptions & other);
 
+  /// Return `true` if logging should be initialized when `rclcpp::Context::init` is called.
+  RCLCPP_PUBLIC
+  bool
+  auto_initialize_logging() const;
+
+  /// Set flag indicating if logging should be initialized or not.
+  RCLCPP_PUBLIC
+  InitOptions &
+  auto_initialize_logging(bool initialize_logging);
+
   /// Assignment operator.
   RCLCPP_PUBLIC
   InitOptions &
@@ -52,6 +72,10 @@ public:
   ~InitOptions();
 
   /// Return the rcl init options.
+  /**
+   * \return the rcl init options.
+   * \throws anything rclcpp::exceptions::throw_from_rcl_error can throw.
+   */
   RCLCPP_PUBLIC
   const rcl_init_options_t *
   get_rcl_init_options() const;
@@ -62,6 +86,7 @@ protected:
 
 private:
   std::unique_ptr<rcl_init_options_t> init_options_;
+  bool initialize_logging_{true};
 };
 
 }  // namespace rclcpp

rclcpp/include/rclcpp/loaned_message.hpp

@@ -52,8 +52,9 @@ public:
    * However, this user code is ought to be usable even when dynamically linked against
    * a middleware which doesn't support message loaning in which case the allocator will be used.
    *
-   * \param pub rclcpp::Publisher instance to which the memory belongs
-   * \param allocator Allocator instance in case middleware can not allocate messages
+   * \param[in] pub rclcpp::Publisher instance to which the memory belongs
+   * \param[in] allocator Allocator instance in case middleware can not allocate messages
+   * \throws anything rclcpp::exceptions::throw_from_rcl_error can throw.
    */
   LoanedMessage(
     const rclcpp::PublisherBase & pub,
@@ -65,7 +66,7 @@ public:
     if (pub_.can_loan_messages()) {
       void * message_ptr = nullptr;
       auto ret = rcl_borrow_loaned_message(
-        pub_.get_publisher_handle(),
+        pub_.get_publisher_handle().get(),
         rosidl_typesupport_cpp::get_message_type_support_handle<MessageT>(),
         &message_ptr);
       if (RCL_RET_OK != ret) {
@@ -98,8 +99,9 @@ public:
    * However, this user code is ought to be usable even when dynamically linked against
    * a middleware which doesn't support message loaning in which case the allocator will be used.
    *
-   * \param pub rclcpp::Publisher instance to which the memory belongs
-   * \param allocator Allocator instance in case middleware can not allocate messages
+   * \param[in] pub rclcpp::Publisher instance to which the memory belongs
+   * \param[in] allocator Allocator instance in case middleware can not allocate messages
+   * \throws anything rclcpp::exceptions::throw_from_rcl_error can throw.
    */
   LoanedMessage(
     const rclcpp::PublisherBase * pub,
@@ -137,7 +139,7 @@ public:
     if (pub_.can_loan_messages()) {
       // return allocated memory to the middleware
       auto ret =
-        rcl_return_loaned_message_from_publisher(pub_.get_publisher_handle(), message_);
+        rcl_return_loaned_message_from_publisher(pub_.get_publisher_handle().get(), message_);
       if (ret != RCL_RET_OK) {
         RCLCPP_ERROR(
           error_logger, "rcl_deallocate_loaned_message failed: %s", rcl_get_error_string().str);

rclcpp/include/rclcpp/memory_strategies.hpp

@@ -23,6 +23,10 @@ namespace rclcpp
 namespace memory_strategies
 {
 
+/// Create a MemoryStrategy sharedPtr
+/**
+ * \return a MemoryStrategy sharedPtr
+ */
 RCLCPP_PUBLIC
 memory_strategy::MemoryStrategy::SharedPtr
 create_default_strategy();

rclcpp/include/rclcpp/memory_strategy.hpp

@@ -56,6 +56,7 @@ public:
   virtual size_t number_of_guard_conditions() const = 0;
   virtual size_t number_of_waitables() const = 0;
 
+  virtual void add_waitable_handle(const rclcpp::Waitable::SharedPtr & waitable) = 0;
   virtual bool add_handles_to_wait_set(rcl_wait_set_t * wait_set) = 0;
   virtual void clear_handles() = 0;
   virtual void remove_null_handles(rcl_wait_set_t * wait_set) = 0;
@@ -66,27 +67,27 @@ public:
 
   virtual void
   get_next_subscription(
-    rclcpp::executor::AnyExecutable & any_exec,
+    rclcpp::AnyExecutable & any_exec,
     const WeakNodeList & weak_nodes) = 0;
 
   virtual void
   get_next_service(
-    rclcpp::executor::AnyExecutable & any_exec,
+    rclcpp::AnyExecutable & any_exec,
     const WeakNodeList & weak_nodes) = 0;
 
   virtual void
   get_next_client(
-    rclcpp::executor::AnyExecutable & any_exec,
+    rclcpp::AnyExecutable & any_exec,
     const WeakNodeList & weak_nodes) = 0;
 
   virtual void
   get_next_timer(
-    rclcpp::executor::AnyExecutable & any_exec,
+    rclcpp::AnyExecutable & any_exec,
     const WeakNodeList & weak_nodes) = 0;
 
   virtual void
   get_next_waitable(
-    rclcpp::executor::AnyExecutable & any_exec,
+    rclcpp::AnyExecutable & any_exec,
     const WeakNodeList & weak_nodes) = 0;
 
   virtual rcl_allocator_t
@@ -114,30 +115,30 @@ public:
 
   static rclcpp::node_interfaces::NodeBaseInterface::SharedPtr
   get_node_by_group(
-    rclcpp::callback_group::CallbackGroup::SharedPtr group,
+    rclcpp::CallbackGroup::SharedPtr group,
     const WeakNodeList & weak_nodes);
 
-  static rclcpp::callback_group::CallbackGroup::SharedPtr
+  static rclcpp::CallbackGroup::SharedPtr
   get_group_by_subscription(
     rclcpp::SubscriptionBase::SharedPtr subscription,
     const WeakNodeList & weak_nodes);
 
-  static rclcpp::callback_group::CallbackGroup::SharedPtr
+  static rclcpp::CallbackGroup::SharedPtr
   get_group_by_service(
     rclcpp::ServiceBase::SharedPtr service,
     const WeakNodeList & weak_nodes);
 
-  static rclcpp::callback_group::CallbackGroup::SharedPtr
+  static rclcpp::CallbackGroup::SharedPtr
   get_group_by_client(
     rclcpp::ClientBase::SharedPtr client,
     const WeakNodeList & weak_nodes);
 
-  static rclcpp::callback_group::CallbackGroup::SharedPtr
+  static rclcpp::CallbackGroup::SharedPtr
   get_group_by_timer(
     rclcpp::TimerBase::SharedPtr timer,
     const WeakNodeList & weak_nodes);
 
-  static rclcpp::callback_group::CallbackGroup::SharedPtr
+  static rclcpp::CallbackGroup::SharedPtr
   get_group_by_waitable(
     rclcpp::Waitable::SharedPtr waitable,
     const WeakNodeList & weak_nodes);

rclcpp/include/rclcpp/message_info.hpp

@@ -0,0 +1,55 @@
+// Copyright 2020 Open Source Robotics Foundation, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef RCLCPP__MESSAGE_INFO_HPP_
+#define RCLCPP__MESSAGE_INFO_HPP_
+
+#include "rmw/types.h"
+
+#include "rclcpp/visibility_control.hpp"
+
+namespace rclcpp
+{
+
+/// Additional meta data about messages taken from subscriptions.
+class RCLCPP_PUBLIC MessageInfo
+{
+public:
+  /// Default empty constructor.
+  MessageInfo() = default;
+
+  /// Conversion constructor, which is intentionally not marked as explicit.
+  /**
+   * \param[in] rmw_message_info message info to initialize the class
+   */
+  // cppcheck-suppress noExplicitConstructor
+  MessageInfo(const rmw_message_info_t & rmw_message_info);  // NOLINT(runtime/explicit)
+
+  virtual ~MessageInfo();
+
+  /// Return the message info as the underlying rmw message info type.
+  const rmw_message_info_t &
+  get_rmw_message_info() const;
+
+  /// Return the message info as the underlying rmw message info type.
+  rmw_message_info_t &
+  get_rmw_message_info();
+
+private:
+  rmw_message_info_t rmw_message_info_;
+};
+
+}  // namespace rclcpp
+
+#endif  // RCLCPP__MESSAGE_INFO_HPP_

rclcpp/include/rclcpp/message_memory_strategy.hpp

@@ -23,6 +23,7 @@
 #include "rclcpp/allocator/allocator_common.hpp"
 #include "rclcpp/exceptions.hpp"
 #include "rclcpp/macros.hpp"
+#include "rclcpp/serialized_message.hpp"
 #include "rclcpp/visibility_control.hpp"
 
 #include "rcutils/logging_macros.h"
@@ -46,10 +47,10 @@ public:
   using MessageAlloc = typename MessageAllocTraits::allocator_type;
   using MessageDeleter = allocator::Deleter<MessageAlloc, MessageT>;
 
-  using SerializedMessageAllocTraits = allocator::AllocRebind<rcl_serialized_message_t, Alloc>;
+  using SerializedMessageAllocTraits = allocator::AllocRebind<rclcpp::SerializedMessage, Alloc>;
   using SerializedMessageAlloc = typename SerializedMessageAllocTraits::allocator_type;
   using SerializedMessageDeleter =
-    allocator::Deleter<SerializedMessageAlloc, rcl_serialized_message_t>;
+    allocator::Deleter<SerializedMessageAlloc, rclcpp::SerializedMessage>;
 
   using BufferAllocTraits = allocator::AllocRebind<char, Alloc>;
   using BufferAlloc = typename BufferAllocTraits::allocator_type;
@@ -86,31 +87,12 @@ public:
     return std::allocate_shared<MessageT, MessageAlloc>(*message_allocator_.get());
   }
 
-  virtual std::shared_ptr<rcl_serialized_message_t> borrow_serialized_message(size_t capacity)
+  virtual std::shared_ptr<rclcpp::SerializedMessage> borrow_serialized_message(size_t capacity)
   {
-    auto msg = new rcl_serialized_message_t;
-    *msg = rmw_get_zero_initialized_serialized_message();
-    auto ret = rmw_serialized_message_init(msg, capacity, &rcutils_allocator_);
-    if (ret != RCL_RET_OK) {
-      rclcpp::exceptions::throw_from_rcl_error(ret);
-    }
-
-    auto serialized_msg = std::shared_ptr<rcl_serialized_message_t>(
-      msg,
-      [](rmw_serialized_message_t * msg) {
-        auto fini_ret = rmw_serialized_message_fini(msg);
-        delete msg;
-        if (fini_ret != RCL_RET_OK) {
-          RCUTILS_LOG_ERROR_NAMED(
-            "rclcpp",
-            "failed to destroy serialized message: %s", rcl_get_error_string().str);
-        }
-      });
-
-    return serialized_msg;
+    return std::make_shared<rclcpp::SerializedMessage>(capacity);
   }
 
-  virtual std::shared_ptr<rcl_serialized_message_t> borrow_serialized_message()
+  virtual std::shared_ptr<rclcpp::SerializedMessage> borrow_serialized_message()
   {
     return borrow_serialized_message(default_buffer_capacity_);
   }
@@ -127,7 +109,8 @@ public:
     msg.reset();
   }
 
-  virtual void return_serialized_message(std::shared_ptr<rcl_serialized_message_t> & serialized_msg)
+  virtual void return_serialized_message(
+    std::shared_ptr<rclcpp::SerializedMessage> & serialized_msg)
   {
     serialized_msg.reset();
   }

rclcpp/include/rclcpp/node.hpp

@@ -26,6 +26,8 @@
 #include <utility>
 #include <vector>
 
+#include "rcutils/macros.h"
+
 #include "rcl/error_handling.h"
 #include "rcl/node.h"
 
@@ -78,6 +80,7 @@ public:
   /**
    * \param[in] node_name Name of the node.
    * \param[in] options Additional options to control creation of the node.
+   * \throws InvalidNamespaceError if the namespace is invalid
    */
   RCLCPP_PUBLIC
   explicit Node(
@@ -89,6 +92,7 @@ public:
    * \param[in] node_name Name of the node.
    * \param[in] namespace_ Namespace of the node.
    * \param[in] options Additional options to control creation of the node.
+   * \throws InvalidNamespaceError if the namespace is invalid
    */
   RCLCPP_PUBLIC
   explicit Node(
@@ -122,6 +126,7 @@ public:
   /// Get the fully-qualified name of the node.
   /**
    * The fully-qualified name includes the local namespace and name of the node.
+   * \return fully-qualified name of the node.
    */
   RCLCPP_PUBLIC
   const char *
@@ -135,12 +140,12 @@ public:
 
   /// Create and return a callback group.
   RCLCPP_PUBLIC
-  rclcpp::callback_group::CallbackGroup::SharedPtr
-  create_callback_group(rclcpp::callback_group::CallbackGroupType group_type);
+  rclcpp::CallbackGroup::SharedPtr
+  create_callback_group(rclcpp::CallbackGroupType group_type);
 
   /// Return the list of callback groups in the node.
   RCLCPP_PUBLIC
-  const std::vector<rclcpp::callback_group::CallbackGroup::WeakPtr> &
+  const std::vector<rclcpp::CallbackGroup::WeakPtr> &
   get_callback_groups() const;
 
   /// Create and return a Publisher.
@@ -156,7 +161,7 @@ public:
    * pub = node->create_publisher<MsgT>("chatter", QoS(10));  // implicitly KeepLast
    * pub = node->create_publisher<MsgT>("chatter", QoS(KeepLast(10)));
    * pub = node->create_publisher<MsgT>("chatter", QoS(KeepAll()));
-   * pub = node->create_publisher<MsgT>("chatter", QoS(1).best_effort().volatile());
+   * pub = node->create_publisher<MsgT>("chatter", QoS(1).best_effort().durability_volatile());
    * {
    *   rclcpp::QoS custom_qos(KeepLast(10), rmw_qos_profile_sensor_data);
    *   pub = node->create_publisher<MsgT>("chatter", custom_qos);
@@ -186,8 +191,8 @@ public:
   /// Create and return a Subscription.
   /**
    * \param[in] topic_name The topic to subscribe on.
+   * \param[in] qos QoS profile for Subcription.
    * \param[in] callback The user-defined callback function to receive a message
-   * \param[in] qos_history_depth The depth of the subscription's incoming message queue.
    * \param[in] options Additional options for the creation of the Subscription.
    * \param[in] msg_mem_strat The message memory strategy to use for allocating messages.
    * \return Shared pointer to the created subscription.
@@ -227,24 +232,37 @@ public:
   create_wall_timer(
     std::chrono::duration<DurationRepT, DurationT> period,
     CallbackT callback,
-    rclcpp::callback_group::CallbackGroup::SharedPtr group = nullptr);
+    rclcpp::CallbackGroup::SharedPtr group = nullptr);
 
-  /* Create and return a Client. */
+  /// Create and return a Client.
+  /**
+   * \param[in] service_name The topic to service on.
+   * \param[in] qos_profile rmw_qos_profile_t Quality of service profile for client.
+   * \param[in] group Callback group to call the service.
+   * \return Shared pointer to the created client.
+   */
   template<typename ServiceT>
   typename rclcpp::Client<ServiceT>::SharedPtr
   create_client(
     const std::string & service_name,
     const rmw_qos_profile_t & qos_profile = rmw_qos_profile_services_default,
-    rclcpp::callback_group::CallbackGroup::SharedPtr group = nullptr);
+    rclcpp::CallbackGroup::SharedPtr group = nullptr);
 
-  /* Create and return a Service. */
+  /// Create and return a Service.
+  /**
+   * \param[in] service_name The topic to service on.
+   * \param[in] callback User-defined callback function.
+   * \param[in] qos_profile rmw_qos_profile_t Quality of service profile for client.
+   * \param[in] group Callback group to call the service.
+   * \return Shared pointer to the created service.
+   */
   template<typename ServiceT, typename CallbackT>
   typename rclcpp::Service<ServiceT>::SharedPtr
   create_service(
     const std::string & service_name,
     CallbackT && callback,
     const rmw_qos_profile_t & qos_profile = rmw_qos_profile_services_default,
-    rclcpp::callback_group::CallbackGroup::SharedPtr group = nullptr);
+    rclcpp::CallbackGroup::SharedPtr group = nullptr);
 
   /// Declare and initialize a parameter, return the effective value.
   /**
@@ -264,7 +282,7 @@ public:
    * If `ignore_override` is `true`, the parameter override will be ignored.
    *
    * This method, if successful, will result in any callback registered with
-   * set_on_parameters_set_callback to be called.
+   * add_on_set_parameters_callback to be called.
    * If that callback prevents the initial value for the parameter from being
    * set then rclcpp::exceptions::InvalidParameterValueException is thrown.
    *
@@ -301,7 +319,7 @@ public:
    *
    * If the type of the default value, and therefore also the type of return
    * value, differs from the initial value provided in the node options, then
-   * a rclcpp::ParameterTypeException may be thrown.
+   * a rclcpp::exceptions::InvalidParameterTypeException may be thrown.
    * To avoid this, use the declare_parameter() method which returns an
    * rclcpp::ParameterValue instead.
    *
@@ -346,7 +364,7 @@ public:
    * by the function call will be ignored.
    *
    * This method, if successful, will result in any callback registered with
-   * set_on_parameters_set_callback to be called, once for each parameter.
+   * add_on_set_parameters_callback to be called, once for each parameter.
    * If that callback prevents the initial value for any parameter from being
    * set then rclcpp::exceptions::InvalidParameterValueException is thrown.
    *
@@ -388,7 +406,7 @@ public:
   /// Undeclare a previously declared parameter.
   /**
    * This method will not cause a callback registered with
-   * set_on_parameters_set_callback to be called.
+   * add_on_set_parameters_callback to be called.
    *
    * \param[in] name The name of the parameter to be undeclared.
    * \throws rclcpp::exceptions::ParameterNotDeclaredException if the parameter
@@ -422,7 +440,7 @@ public:
    * Parameter overrides are ignored by set_parameter.
    *
    * This method will result in any callback registered with
-   * set_on_parameters_set_callback to be called.
+   * add_on_set_parameters_callback to be called.
    * If the callback prevents the parameter from being set, then it will be
    * reflected in the SetParametersResult that is returned, but no exception
    * will be thrown.
@@ -463,7 +481,7 @@ public:
    * corresponding SetParametersResult in the vector returned by this function.
    *
    * This method will result in any callback registered with
-   * set_on_parameters_set_callback to be called, once for each parameter.
+   * add_on_set_parameters_callback to be called, once for each parameter.
    * If the callback prevents the parameter from being set, then, as mentioned
    * before, it will be reflected in the corresponding SetParametersResult
    * that is returned, but no exception will be thrown.
@@ -494,7 +512,7 @@ public:
    * If the exception is thrown then none of the parameters will have been set.
    *
    * This method will result in any callback registered with
-   * set_on_parameters_set_callback to be called, just one time.
+   * add_on_set_parameters_callback to be called, just one time.
    * If the callback prevents the parameters from being set, then it will be
    * reflected in the SetParametersResult which is returned, but no exception
    * will be thrown.
@@ -672,6 +690,7 @@ public:
    * \throws rclcpp::exceptions::ParameterNotDeclaredException if the
    *   parameter has not been declared and undeclared parameters are not
    *   allowed.
+   * \throws std::runtime_error if the number of described parameters is more than one
    */
   RCLCPP_PUBLIC
   rcl_interfaces::msg::ParameterDescriptor
@@ -694,6 +713,7 @@ public:
    * \throws rclcpp::exceptions::ParameterNotDeclaredException if any of the
    *   parameters have not been declared and undeclared parameters are not
    *   allowed.
+   * \throws std::runtime_error if the number of described parameters is more than one
    */
   RCLCPP_PUBLIC
   std::vector<rcl_interfaces::msg::ParameterDescriptor>
@@ -774,7 +794,7 @@ public:
    * of the {get,list,describe}_parameter() methods), but may *not* modify
    * other parameters (by calling any of the {set,declare}_parameter() methods)
    * or modify the registered callback itself (by calling the
-   * set_on_parameters_set_callback() method).  If a callback tries to do any
+   * add_on_set_parameters_callback() method).  If a callback tries to do any
    * of the latter things,
    * rclcpp::exceptions::ParameterModifiedInCallbackException will be thrown.
    *
@@ -794,6 +814,7 @@ public:
    * \throws std::bad_alloc if the allocation of the OnSetParametersCallbackHandle fails.
    */
   RCLCPP_PUBLIC
+  RCUTILS_WARN_UNUSED
   OnSetParametersCallbackHandle::SharedPtr
   add_on_set_parameters_callback(OnParametersSetCallbackType callback);
 
@@ -826,6 +847,7 @@ public:
 
   /// Register a callback to be called anytime a parameter is about to be changed.
   /**
+   * \deprecated Use add_on_set_parameters_callback instead.
    * With this method, only one callback can be set at a time. The callback that was previously
    * set by this method is returned or `nullptr` if no callback was previously set.
    *
@@ -838,6 +860,7 @@ public:
    * \return The previous callback that was registered, if there was one,
    *   otherwise nullptr.
    */
+  [[deprecated("use add_on_set_parameters_callback(OnParametersSetCallbackType callback) instead")]]
   RCLCPP_PUBLIC
   OnParametersSetCallbackType
   set_on_parameters_set_callback(rclcpp::Node::OnParametersSetCallbackType callback);
@@ -851,22 +874,106 @@ public:
   std::vector<std::string>
   get_node_names() const;
 
+  /// Return a map of existing topic names to list of topic types.
+  /**
+   * \return a map of existing topic names to list of topic types.
+   * \throws std::runtime_error anything that rcl_error can throw
+   */
   RCLCPP_PUBLIC
   std::map<std::string, std::vector<std::string>>
   get_topic_names_and_types() const;
 
+  /// Return a map of existing service names to list of service types.
+  /**
+   * \return a map of existing service names to list of service types.
+   * \throws std::runtime_error anything that rcl_error can throw
+   */
   RCLCPP_PUBLIC
   std::map<std::string, std::vector<std::string>>
   get_service_names_and_types() const;
 
+  /// Return a map of existing service names to list of service types for a specific node.
+  /**
+   * This function only considers services - not clients.
+   * The returned names are the actual names used and do not have remap rules applied.
+   *
+   * \param[in] node_name name of the node.
+   * \param[in] namespace_ namespace of the node.
+   * \return a map of existing service names to list of service types.
+   * \throws std::runtime_error anything that rcl_error can throw.
+   */
+  RCLCPP_PUBLIC
+  std::map<std::string, std::vector<std::string>>
+  get_service_names_and_types_by_node(
+    const std::string & node_name,
+    const std::string & namespace_) const;
+
   RCLCPP_PUBLIC
   size_t
   count_publishers(const std::string & topic_name) const;
 
+  /// Return the number of subscribers who have created a subscription for a given topic.
+  /**
+   * \param[in] topic_name the topic_name on which to count the subscribers.
+   * \return number of subscribers who have created a subscription for a given topic.
+   * \throws std::runtime_error if publishers could not be counted
+   */
   RCLCPP_PUBLIC
   size_t
   count_subscribers(const std::string & topic_name) const;
 
+  /// Return the topic endpoint information about publishers on a given topic.
+  /**
+   * The returned parameter is a list of topic endpoint information, where each item will contain
+   * the node name, node namespace, topic type, endpoint type, topic endpoint's GID, and its QoS
+   * profile.
+   *
+   * When the `no_mangle` parameter is `true`, the provided `topic_name` should be a valid topic
+   * name for the middleware (useful when combining ROS with native middleware (e.g. DDS) apps).
+   * When the `no_mangle` parameter is `false`, the provided `topic_name` should follow
+   * ROS topic name conventions.
+   *
+   * `topic_name` may be a relative, private, or fully qualified topic name.
+   * A relative or private topic will be expanded using this node's namespace and name.
+   * The queried `topic_name` is not remapped.
+   *
+   * \param[in] topic_name the topic_name on which to find the publishers.
+   * \param[in] no_mangle if `true`, `topic_name` needs to be a valid middleware topic name,
+   *   otherwise it should be a valid ROS topic name. Defaults to `false`.
+   * \return a list of TopicEndpointInfo representing all the publishers on this topic.
+   * \throws InvalidTopicNameError if the given topic_name is invalid.
+   * \throws std::runtime_error if internal error happens.
+   */
+  RCLCPP_PUBLIC
+  std::vector<rclcpp::TopicEndpointInfo>
+  get_publishers_info_by_topic(const std::string & topic_name, bool no_mangle = false) const;
+
+  /// Return the topic endpoint information about subscriptions on a given topic.
+  /**
+   * The returned parameter is a list of topic endpoint information, where each item will contain
+   * the node name, node namespace, topic type, endpoint type, topic endpoint's GID, and its QoS
+   * profile.
+   *
+   * When the `no_mangle` parameter is `true`, the provided `topic_name` should be a valid topic
+   * name for the middleware (useful when combining ROS with native middleware (e.g. DDS) apps).
+   * When the `no_mangle` parameter is `false`, the provided `topic_name` should follow
+   * ROS topic name conventions.
+   *
+   * `topic_name` may be a relative, private, or fully qualified topic name.
+   * A relative or private topic will be expanded using this node's namespace and name.
+   * The queried `topic_name` is not remapped.
+   *
+   * \param[in] topic_name the topic_name on which to find the subscriptions.
+   * \param[in] no_mangle if `true`, `topic_name` needs to be a valid middleware topic name,
+   *   otherwise it should be a valid ROS topic name. Defaults to `false`.
+   * \return a list of TopicEndpointInfo representing all the subscriptions on this topic.
+   * \throws InvalidTopicNameError if the given topic_name is invalid.
+   * \throws std::runtime_error if internal error happens.
+   */
+  RCLCPP_PUBLIC
+  std::vector<rclcpp::TopicEndpointInfo>
+  get_subscriptions_info_by_topic(const std::string & topic_name, bool no_mangle = false) const;
+
   /// Return a graph event, which will be set anytime a graph change occurs.
   /* The graph Event object is a loan which must be returned.
    * The Event object is scoped and therefore to return the loan just let it go
@@ -880,6 +987,9 @@ public:
   /**
    * The given Event must be acquire through the get_graph_event() method.
    *
+   * \param[in] event pointer to an Event to wait for
+   * \param[in] timeout nanoseconds to wait for the Event to change the state
+   *
    * \throws InvalidEventError if the given event is nullptr
    * \throws EventNotRegisteredError if the given event was not acquired with
    *   get_graph_event().
@@ -890,13 +1000,29 @@ public:
     rclcpp::Event::SharedPtr event,
     std::chrono::nanoseconds timeout);
 
+  /// Get a clock as a non-const shared pointer which is managed by the node.
+  /**
+   * \sa rclcpp::node_interfaces::NodeClock::get_clock
+   */
   RCLCPP_PUBLIC
   rclcpp::Clock::SharedPtr
   get_clock();
 
+  /// Get a clock as a const shared pointer which is managed by the node.
+  /**
+   * \sa rclcpp::node_interfaces::NodeClock::get_clock
+   */
+  RCLCPP_PUBLIC
+  rclcpp::Clock::ConstSharedPtr
+  get_clock() const;
+
+  /// Returns current time from the time source specified by clock_type.
+  /**
+   * \sa rclcpp::Clock::now
+   */
   RCLCPP_PUBLIC
   Time
-  now();
+  now() const;
 
   /// Return the Node's internal NodeBaseInterface implementation.
   RCLCPP_PUBLIC
@@ -943,7 +1069,7 @@ public:
   rclcpp::node_interfaces::NodeParametersInterface::SharedPtr
   get_node_parameters_interface();
 
-  /// Return the Node's internal NodeParametersInterface implementation.
+  /// Return the Node's internal NodeTimeSourceInterface implementation.
   RCLCPP_PUBLIC
   rclcpp::node_interfaces::NodeTimeSourceInterface::SharedPtr
   get_node_time_source_interface();
@@ -1055,19 +1181,6 @@ public:
   const rclcpp::NodeOptions &
   get_node_options() const;
 
-  /// Manually assert that this Node is alive (for RMW_QOS_POLICY_LIVELINESS_MANUAL_BY_NODE).
-  /**
-   * If the rmw Liveliness policy is set to RMW_QOS_POLICY_LIVELINESS_MANUAL_BY_NODE, the creator
-   * of this node may manually call `assert_liveliness` at some point in time to signal to the rest
-   * of the system that this Node is still alive.
-   *
-   * \return `true` if the liveliness was asserted successfully, otherwise `false`
-   */
-  RCLCPP_PUBLIC
-  RCUTILS_WARN_UNUSED
-  bool
-  assert_liveliness() const;
-
 protected:
   /// Construct a sub-node, which will extend the namespace of all entities created with it.
   /**
@@ -1086,7 +1199,7 @@ private:
 
   RCLCPP_PUBLIC
   bool
-  group_in_node(callback_group::CallbackGroup::SharedPtr group);
+  group_in_node(CallbackGroup::SharedPtr group);
 
   rclcpp::node_interfaces::NodeBaseInterface::SharedPtr node_base_;
   rclcpp::node_interfaces::NodeGraphInterface::SharedPtr node_graph_;

rclcpp/include/rclcpp/node_impl.hpp

@@ -19,6 +19,7 @@
 #include <rmw/rmw.h>
 
 #include <algorithm>
+#include <chrono>
 #include <cstdlib>
 #include <iostream>
 #include <limits>
@@ -33,15 +34,16 @@
 #include "rcl/publisher.h"
 #include "rcl/subscription.h"
 
-#include "rcl_interfaces/msg/intra_process_message.hpp"
-
 #include "rclcpp/contexts/default_context.hpp"
 #include "rclcpp/create_client.hpp"
 #include "rclcpp/create_publisher.hpp"
 #include "rclcpp/create_service.hpp"
+#include "rclcpp/create_timer.hpp"
 #include "rclcpp/create_subscription.hpp"
+#include "rclcpp/detail/resolve_enable_topic_statistics.hpp"
 #include "rclcpp/parameter.hpp"
 #include "rclcpp/qos.hpp"
+#include "rclcpp/timer.hpp"
 #include "rclcpp/type_support_decl.hpp"
 #include "rclcpp/visibility_control.hpp"
 
@@ -107,14 +109,14 @@ typename rclcpp::WallTimer<CallbackT>::SharedPtr
 Node::create_wall_timer(
   std::chrono::duration<DurationRepT, DurationT> period,
   CallbackT callback,
-  rclcpp::callback_group::CallbackGroup::SharedPtr group)
+  rclcpp::CallbackGroup::SharedPtr group)
 {
-  auto timer = rclcpp::WallTimer<CallbackT>::make_shared(
-    std::chrono::duration_cast<std::chrono::nanoseconds>(period),
+  return rclcpp::create_wall_timer(
+    period,
     std::move(callback),
-    this->node_base_->get_context());
-  node_timers_->add_timer(timer, group);
-  return timer;
+    group,
+    this->node_base_.get(),
+    this->node_timers_.get());
 }
 
 template<typename ServiceT>
@@ -122,7 +124,7 @@ typename Client<ServiceT>::SharedPtr
 Node::create_client(
   const std::string & service_name,
   const rmw_qos_profile_t & qos_profile,
-  rclcpp::callback_group::CallbackGroup::SharedPtr group)
+  rclcpp::CallbackGroup::SharedPtr group)
 {
   return rclcpp::create_client<ServiceT>(
     node_base_,
@@ -139,7 +141,7 @@ Node::create_service(
   const std::string & service_name,
   CallbackT && callback,
   const rmw_qos_profile_t & qos_profile,
-  rclcpp::callback_group::CallbackGroup::SharedPtr group)
+  rclcpp::CallbackGroup::SharedPtr group)
 {
   return rclcpp::create_service<ServiceT, CallbackT>(
     node_base_,
@@ -158,12 +160,16 @@ Node::declare_parameter(
   const rcl_interfaces::msg::ParameterDescriptor & parameter_descriptor,
   bool ignore_override)
 {
-  return this->declare_parameter(
-    name,
-    rclcpp::ParameterValue(default_value),
-    parameter_descriptor,
-    ignore_override
-  ).get<ParameterT>();
+  try {
+    return this->declare_parameter(
+      name,
+      rclcpp::ParameterValue(default_value),
+      parameter_descriptor,
+      ignore_override
+    ).get<ParameterT>();
+  } catch (const ParameterTypeException & ex) {
+    throw exceptions::InvalidParameterTypeException(name, ex.what());
+  }
 }
 
 template<typename ParameterT>

rclcpp/include/rclcpp/node_interfaces/get_node_base_interface.hpp

@@ -1,149 +0,0 @@
-// Copyright 2019 Open Source Robotics Foundation, Inc.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//     http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-#ifndef RCLCPP__NODE_INTERFACES__GET_NODE_BASE_INTERFACE_HPP_
-#define RCLCPP__NODE_INTERFACES__GET_NODE_BASE_INTERFACE_HPP_
-
-#include <memory>
-#include <utility>
-#include <type_traits>
-
-#include "rclcpp/node_interfaces/node_base_interface.hpp"
-
-/// This header provides the get_node_base_interface() template function.
-/**
- * This function is useful for getting the NodeBaseInterface pointer from
- * various kinds of Node-like classes.
- *
- * It's able to get the NodeBaseInterface pointer so long as the class
- * has a method called ``get_node_base_interface()`` which returns
- * either a pointer (const or not) to a NodeBaseInterface or a
- * std::shared_ptr to a NodeBaseInterface.
- */
-
-namespace rclcpp
-{
-namespace node_interfaces
-{
-
-namespace detail
-{
-
-// This is a meta-programming checker for if a given Node-like object has a
-// getter called get_node_base_interface() which returns various types,
-// e.g. const pointer or a shared pointer.
-template<typename NodeType, typename ReturnType>
-struct has_get_node_base_interface
-{
-private:
-  template<typename T>
-  static constexpr
-  auto
-  check(T *)->typename std::is_same<
-    decltype(std::declval<T>().get_node_base_interface()),
-    ReturnType
-  >::type;
-
-  template<typename>
-  static constexpr
-  std::false_type
-  check(...);
-
-public:
-  using type = decltype(check<NodeType>(nullptr));
-  static constexpr bool value = type::value;
-};
-
-// If NodeType is a pointer to NodeBaseInterface already (just normal function overload).
-inline
-rclcpp::node_interfaces::NodeBaseInterface *
-get_node_base_interface_from_pointer(rclcpp::node_interfaces::NodeBaseInterface * pointer)
-{
-  return pointer;
-}
-
-// If NodeType has a method called get_node_base_interface() which returns a shared pointer.
-template<
-  typename NodeType,
-  typename std::enable_if<has_get_node_base_interface<
-    typename std::remove_pointer<NodeType>::type,
-    std::shared_ptr<rclcpp::node_interfaces::NodeBaseInterface>
-  >::value, int>::type = 0
->
-rclcpp::node_interfaces::NodeBaseInterface *
-get_node_base_interface_from_pointer(NodeType node_pointer)
-{
-  return node_pointer->get_node_base_interface().get();
-}
-
-// If NodeType has a method called get_node_base_interface() which returns a pointer.
-template<
-  typename NodeType,
-  typename std::enable_if<has_get_node_base_interface<
-    typename std::remove_pointer<NodeType>::type,
-    rclcpp::node_interfaces::NodeBaseInterface *
-  >::value, int>::type = 0
->
-rclcpp::node_interfaces::NodeBaseInterface *
-get_node_base_interface_from_pointer(NodeType node_pointer)
-{
-  return node_pointer->get_node_base_interface();
-}
-
-// Forward shared_ptr's to const node pointer signatures.
-template<
-  typename NodeType,
-  typename std::enable_if<std::is_same<
-    NodeType,
-    typename std::shared_ptr<typename std::remove_pointer<NodeType>::type::element_type> *
-  >::value, int>::type = 0
->
-rclcpp::node_interfaces::NodeBaseInterface *
-get_node_base_interface_from_pointer(NodeType node_shared_pointer)
-{
-  return get_node_base_interface_from_pointer(node_shared_pointer->get());
-}
-
-}  // namespace detail
-
-/// Get the NodeBaseInterface as a pointer from a pointer to a "Node like" object.
-template<
-  typename NodeType,
-  typename std::enable_if<std::is_pointer<NodeType>::value, int>::type = 0
->
-rclcpp::node_interfaces::NodeBaseInterface *
-get_node_base_interface(NodeType node_pointer)
-{
-  // Forward pointers to detail implmentation directly.
-  return detail::get_node_base_interface_from_pointer(node_pointer);
-}
-
-/// Get the NodeBaseInterface as a pointer from a "Node like" object.
-template<
-  typename NodeType,
-  typename std::enable_if<
-    !std::is_pointer<typename std::remove_reference<NodeType>::type>::value, int
-  >::type = 0
->
-rclcpp::node_interfaces::NodeBaseInterface *
-get_node_base_interface(NodeType && node_reference)
-{
-  // Forward references to detail implmentation as a pointer.
-  return detail::get_node_base_interface_from_pointer(&node_reference);
-}
-
-}  // namespace node_interfaces
-}  // namespace rclcpp
-
-#endif  // RCLCPP__NODE_INTERFACES__GET_NODE_BASE_INTERFACE_HPP_

rclcpp/include/rclcpp/node_interfaces/get_node_timers_interface.hpp

@@ -1,149 +0,0 @@
-// Copyright 2019 Open Source Robotics Foundation, Inc.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//     http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-#ifndef RCLCPP__NODE_INTERFACES__GET_NODE_TIMERS_INTERFACE_HPP_
-#define RCLCPP__NODE_INTERFACES__GET_NODE_TIMERS_INTERFACE_HPP_
-
-#include <memory>
-#include <utility>
-#include <type_traits>
-
-#include "rclcpp/node_interfaces/node_timers_interface.hpp"
-
-/// This header provides the get_node_timers_interface() template function.
-/**
- * This function is useful for getting the NodeTimersInterface pointer from
- * various kinds of Node-like classes.
- *
- * It's able to get the NodeTimersInterface pointer so long as the class
- * has a method called ``get_node_timers_interface()`` which returns
- * either a pointer (const or not) to a NodeTimersInterface or a
- * std::shared_ptr to a NodeTimersInterface.
- */
-
-namespace rclcpp
-{
-namespace node_interfaces
-{
-
-namespace detail
-{
-
-// This is a meta-programming checker for if a given Node-like object has a
-// getter called get_node_timers_interface() which returns various types,
-// e.g. const pointer or a shared pointer.
-template<typename NodeType, typename ReturnType>
-struct has_get_node_timers_interface
-{
-private:
-  template<typename T>
-  static constexpr
-  auto
-  check(T *)->typename std::is_same<
-    decltype(std::declval<T>().get_node_timers_interface()),
-    ReturnType
-  >::type;
-
-  template<typename>
-  static constexpr
-  std::false_type
-  check(...);
-
-public:
-  using type = decltype(check<NodeType>(nullptr));
-  static constexpr bool value = type::value;
-};
-
-// If NodeType is a pointer to NodeTimersInterface already (just normal function overload).
-inline
-rclcpp::node_interfaces::NodeTimersInterface *
-get_node_timers_interface_from_pointer(rclcpp::node_interfaces::NodeTimersInterface * pointer)
-{
-  return pointer;
-}
-
-// If NodeType has a method called get_node_timers_interface() which returns a shared pointer.
-template<
-  typename NodeType,
-  typename std::enable_if<has_get_node_timers_interface<
-    typename std::remove_pointer<NodeType>::type,
-    std::shared_ptr<rclcpp::node_interfaces::NodeTimersInterface>
-  >::value, int>::type = 0
->
-rclcpp::node_interfaces::NodeTimersInterface *
-get_node_timers_interface_from_pointer(NodeType node_pointer)
-{
-  return node_pointer->get_node_timers_interface().get();
-}
-
-// If NodeType has a method called get_node_timers_interface() which returns a pointer.
-template<
-  typename NodeType,
-  typename std::enable_if<has_get_node_timers_interface<
-    typename std::remove_pointer<NodeType>::type,
-    rclcpp::node_interfaces::NodeTimersInterface *
-  >::value, int>::type = 0
->
-rclcpp::node_interfaces::NodeTimersInterface *
-get_node_timers_interface_from_pointer(NodeType node_pointer)
-{
-  return node_pointer->get_node_timers_interface();
-}
-
-// Forward shared_ptr's to const node pointer signatures.
-template<
-  typename NodeType,
-  typename std::enable_if<std::is_same<
-    NodeType,
-    typename std::shared_ptr<typename std::remove_pointer<NodeType>::type::element_type> *
-  >::value, int>::type = 0
->
-rclcpp::node_interfaces::NodeTimersInterface *
-get_node_timers_interface_from_pointer(NodeType node_shared_pointer)
-{
-  return get_node_timers_interface_from_pointer(node_shared_pointer->get());
-}
-
-}  // namespace detail
-
-/// Get the NodeTimersInterface as a pointer from a pointer to a "Node like" object.
-template<
-  typename NodeType,
-  typename std::enable_if<std::is_pointer<NodeType>::value, int>::type = 0
->
-rclcpp::node_interfaces::NodeTimersInterface *
-get_node_timers_interface(NodeType node_pointer)
-{
-  // Forward pointers to detail implmentation directly.
-  return detail::get_node_timers_interface_from_pointer(node_pointer);
-}
-
-/// Get the NodeTimersInterface as a pointer from a "Node like" object.
-template<
-  typename NodeType,
-  typename std::enable_if<
-    !std::is_pointer<typename std::remove_reference<NodeType>::type>::value, int
-  >::type = 0
->
-rclcpp::node_interfaces::NodeTimersInterface *
-get_node_timers_interface(NodeType && node_reference)
-{
-  // Forward references to detail implmentation as a pointer.
-  return detail::get_node_timers_interface_from_pointer(&node_reference);
-}
-
-}  // namespace node_interfaces
-}  // namespace rclcpp
-
-#endif  // RCLCPP__NODE_INTERFACES__GET_NODE_TIMERS_INTERFACE_HPP_

rclcpp/include/rclcpp/node_interfaces/get_node_topics_interface.hpp

@@ -1,149 +0,0 @@
-// Copyright 2019 Open Source Robotics Foundation, Inc.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//     http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-#ifndef RCLCPP__NODE_INTERFACES__GET_NODE_TOPICS_INTERFACE_HPP_
-#define RCLCPP__NODE_INTERFACES__GET_NODE_TOPICS_INTERFACE_HPP_
-
-#include <memory>
-#include <utility>
-#include <type_traits>
-
-#include "rclcpp/node_interfaces/node_topics_interface.hpp"
-
-/// This header provides the get_node_topics_interface() template function.
-/**
- * This function is useful for getting the NodeTopicsInterface pointer from
- * various kinds of Node-like classes.
- *
- * It's able to get the NodeTopicsInterface pointer so long as the class
- * has a method called ``get_node_topics_interface()`` which returns
- * either a pointer (const or not) to a NodeTopicsInterface or a
- * std::shared_ptr to a NodeTopicsInterface.
- */
-
-namespace rclcpp
-{
-namespace node_interfaces
-{
-
-namespace detail
-{
-
-// This is a meta-programming checker for if a given Node-like object has a
-// getter called get_node_topics_interface() which returns various types,
-// e.g. const pointer or a shared pointer.
-template<typename NodeType, typename ReturnType>
-struct has_get_node_topics_interface
-{
-private:
-  template<typename T>
-  static constexpr
-  auto
-  check(T *)->typename std::is_same<
-    decltype(std::declval<T>().get_node_topics_interface()),
-    ReturnType
-  >::type;
-
-  template<typename>
-  static constexpr
-  std::false_type
-  check(...);
-
-public:
-  using type = decltype(check<NodeType>(nullptr));
-  static constexpr bool value = type::value;
-};
-
-// If NodeType is a pointer to NodeTopicsInterface already (just normal function overload).
-inline
-rclcpp::node_interfaces::NodeTopicsInterface *
-get_node_topics_interface_from_pointer(rclcpp::node_interfaces::NodeTopicsInterface * pointer)
-{
-  return pointer;
-}
-
-// If NodeType has a method called get_node_topics_interface() which returns a shared pointer.
-template<
-  typename NodeType,
-  typename std::enable_if<has_get_node_topics_interface<
-    typename std::remove_pointer<NodeType>::type,
-    std::shared_ptr<rclcpp::node_interfaces::NodeTopicsInterface>
-  >::value, int>::type = 0
->
-rclcpp::node_interfaces::NodeTopicsInterface *
-get_node_topics_interface_from_pointer(NodeType node_pointer)
-{
-  return node_pointer->get_node_topics_interface().get();
-}
-
-// If NodeType has a method called get_node_topics_interface() which returns a pointer.
-template<
-  typename NodeType,
-  typename std::enable_if<has_get_node_topics_interface<
-    typename std::remove_pointer<NodeType>::type,
-    rclcpp::node_interfaces::NodeTopicsInterface *
-  >::value, int>::type = 0
->
-rclcpp::node_interfaces::NodeTopicsInterface *
-get_node_topics_interface_from_pointer(NodeType node_pointer)
-{
-  return node_pointer->get_node_topics_interface();
-}
-
-// Forward shared_ptr's to const node pointer signatures.
-template<
-  typename NodeType,
-  typename std::enable_if<std::is_same<
-    NodeType,
-    typename std::shared_ptr<typename std::remove_pointer<NodeType>::type::element_type> *
-  >::value, int>::type = 0
->
-rclcpp::node_interfaces::NodeTopicsInterface *
-get_node_topics_interface_from_pointer(NodeType node_shared_pointer)
-{
-  return get_node_topics_interface_from_pointer(node_shared_pointer->get());
-}
-
-}  // namespace detail
-
-/// Get the NodeTopicsInterface as a pointer from a pointer to a "Node like" object.
-template<
-  typename NodeType,
-  typename std::enable_if<std::is_pointer<NodeType>::value, int>::type = 0
->
-rclcpp::node_interfaces::NodeTopicsInterface *
-get_node_topics_interface(NodeType node_pointer)
-{
-  // Forward pointers to detail implmentation directly.
-  return detail::get_node_topics_interface_from_pointer(node_pointer);
-}
-
-/// Get the NodeTopicsInterface as a pointer from a "Node like" object.
-template<
-  typename NodeType,
-  typename std::enable_if<
-    !std::is_pointer<typename std::remove_reference<NodeType>::type>::value, int
-  >::type = 0
->
-rclcpp::node_interfaces::NodeTopicsInterface *
-get_node_topics_interface(NodeType && node_reference)
-{
-  // Forward references to detail implmentation as a pointer.
-  return detail::get_node_topics_interface_from_pointer(&node_reference);
-}
-
-}  // namespace node_interfaces
-}  // namespace rclcpp
-
-#endif  // RCLCPP__NODE_INTERFACES__GET_NODE_TOPICS_INTERFACE_HPP_

rclcpp/include/rclcpp/node_interfaces/node_base.hpp

@@ -23,7 +23,6 @@
 #include "rclcpp/context.hpp"
 #include "rclcpp/macros.hpp"
 #include "rclcpp/node_interfaces/node_base_interface.hpp"
-#include "rclcpp/node_options.hpp"
 #include "rclcpp/visibility_control.hpp"
 
 namespace rclcpp
@@ -43,107 +42,91 @@ public:
     const std::string & namespace_,
     rclcpp::Context::SharedPtr context,
     const rcl_node_options_t & rcl_node_options,
-    bool use_intra_process_default);
+    bool use_intra_process_default,
+    bool enable_topic_statistics_default);
 
   RCLCPP_PUBLIC
   virtual
   ~NodeBase();
 
   RCLCPP_PUBLIC
-  virtual
   const char *
-  get_name() const;
+  get_name() const override;
 
   RCLCPP_PUBLIC
-  virtual
   const char *
-  get_namespace() const;
+  get_namespace() const override;
 
   RCLCPP_PUBLIC
-  virtual
   const char *
-  get_fully_qualified_name() const;
+  get_fully_qualified_name() const override;
 
   RCLCPP_PUBLIC
-  virtual
   rclcpp::Context::SharedPtr
-  get_context();
+  get_context() override;
 
   RCLCPP_PUBLIC
-  virtual
   rcl_node_t *
-  get_rcl_node_handle();
+  get_rcl_node_handle() override;
 
   RCLCPP_PUBLIC
-  virtual
   const rcl_node_t *
-  get_rcl_node_handle() const;
+  get_rcl_node_handle() const override;
 
   RCLCPP_PUBLIC
-  virtual
   std::shared_ptr<rcl_node_t>
-  get_shared_rcl_node_handle();
+  get_shared_rcl_node_handle() override;
 
   RCLCPP_PUBLIC
-  virtual
   std::shared_ptr<const rcl_node_t>
-  get_shared_rcl_node_handle() const;
+  get_shared_rcl_node_handle() const override;
+
+  RCLCPP_PUBLIC
+  rclcpp::CallbackGroup::SharedPtr
+  create_callback_group(rclcpp::CallbackGroupType group_type) override;
+
+  RCLCPP_PUBLIC
+  rclcpp::CallbackGroup::SharedPtr
+  get_default_callback_group() override;
 
   RCLCPP_PUBLIC
-  virtual
   bool
-  assert_liveliness() const;
+  callback_group_in_node(rclcpp::CallbackGroup::SharedPtr group) override;
 
   RCLCPP_PUBLIC
-  virtual
-  rclcpp::callback_group::CallbackGroup::SharedPtr
-  create_callback_group(rclcpp::callback_group::CallbackGroupType group_type);
+  const std::vector<rclcpp::CallbackGroup::WeakPtr> &
+  get_callback_groups() const override;
 
   RCLCPP_PUBLIC
-  virtual
-  rclcpp::callback_group::CallbackGroup::SharedPtr
-  get_default_callback_group();
-
-  RCLCPP_PUBLIC
-  virtual
-  bool
-  callback_group_in_node(rclcpp::callback_group::CallbackGroup::SharedPtr group);
-
-  RCLCPP_PUBLIC
-  virtual
-  const std::vector<rclcpp::callback_group::CallbackGroup::WeakPtr> &
-  get_callback_groups() const;
-
-  RCLCPP_PUBLIC
-  virtual
   std::atomic_bool &
-  get_associated_with_executor_atomic();
+  get_associated_with_executor_atomic() override;
 
   RCLCPP_PUBLIC
-  virtual
   rcl_guard_condition_t *
-  get_notify_guard_condition();
+  get_notify_guard_condition() override;
 
   RCLCPP_PUBLIC
-  virtual
   std::unique_lock<std::recursive_mutex>
-  acquire_notify_guard_condition_lock() const;
+  acquire_notify_guard_condition_lock() const override;
 
   RCLCPP_PUBLIC
-  virtual
   bool
-  get_use_intra_process_default() const;
+  get_use_intra_process_default() const override;
+
+  bool
+  get_enable_topic_statistics_default() const override;
 
 private:
   RCLCPP_DISABLE_COPY(NodeBase)
 
   rclcpp::Context::SharedPtr context_;
   bool use_intra_process_default_;
+  bool enable_topic_statistics_default_;
 
   std::shared_ptr<rcl_node_t> node_handle_;
 
-  rclcpp::callback_group::CallbackGroup::SharedPtr default_callback_group_;
-  std::vector<rclcpp::callback_group::CallbackGroup::WeakPtr> callback_groups_;
+  rclcpp::CallbackGroup::SharedPtr default_callback_group_;
+  std::vector<rclcpp::CallbackGroup::WeakPtr> callback_groups_;
 
   std::atomic_bool associated_with_executor_;
 

rclcpp/include/rclcpp/node_interfaces/node_base_interface.hpp

@@ -102,34 +102,28 @@ public:
   std::shared_ptr<const rcl_node_t>
   get_shared_rcl_node_handle() const = 0;
 
-  /// Manually assert that this Node is alive (for RMW_QOS_POLICY_LIVELINESS_MANUAL_BY_NODE).
-  RCLCPP_PUBLIC
-  virtual
-  bool
-  assert_liveliness() const = 0;
-
   /// Create and return a callback group.
   RCLCPP_PUBLIC
   virtual
-  rclcpp::callback_group::CallbackGroup::SharedPtr
-  create_callback_group(rclcpp::callback_group::CallbackGroupType group_type) = 0;
+  rclcpp::CallbackGroup::SharedPtr
+  create_callback_group(rclcpp::CallbackGroupType group_type) = 0;
 
   /// Return the default callback group.
   RCLCPP_PUBLIC
   virtual
-  rclcpp::callback_group::CallbackGroup::SharedPtr
+  rclcpp::CallbackGroup::SharedPtr
   get_default_callback_group() = 0;
 
   /// Return true if the given callback group is associated with this node.
   RCLCPP_PUBLIC
   virtual
   bool
-  callback_group_in_node(rclcpp::callback_group::CallbackGroup::SharedPtr group) = 0;
+  callback_group_in_node(rclcpp::CallbackGroup::SharedPtr group) = 0;
 
   /// Return list of callback groups associated with this node.
   RCLCPP_PUBLIC
   virtual
-  const std::vector<rclcpp::callback_group::CallbackGroup::WeakPtr> &
+  const std::vector<rclcpp::CallbackGroup::WeakPtr> &
   get_callback_groups() const = 0;
 
   /// Return the atomic bool which is used to ensure only one executor is used.
@@ -161,6 +155,12 @@ public:
   virtual
   bool
   get_use_intra_process_default() const = 0;
+
+  /// Return the default preference for enabling topic statistics collection.
+  RCLCPP_PUBLIC
+  virtual
+  bool
+  get_enable_topic_statistics_default() const = 0;
 };
 
 }  // namespace node_interfaces

rclcpp/include/rclcpp/node_interfaces/node_clock.hpp

@@ -15,14 +15,14 @@
 #ifndef RCLCPP__NODE_INTERFACES__NODE_CLOCK_HPP_
 #define RCLCPP__NODE_INTERFACES__NODE_CLOCK_HPP_
 
-#include "rclcpp/callback_group.hpp"
 #include "rclcpp/clock.hpp"
 #include "rclcpp/macros.hpp"
 #include "rclcpp/node_interfaces/node_base_interface.hpp"
 #include "rclcpp/node_interfaces/node_clock_interface.hpp"
-#include "rclcpp/node_interfaces/node_parameters_interface.hpp"
+#include "rclcpp/node_interfaces/node_graph_interface.hpp"
+#include "rclcpp/node_interfaces/node_logging_interface.hpp"
+#include "rclcpp/node_interfaces/node_services_interface.hpp"
 #include "rclcpp/node_interfaces/node_topics_interface.hpp"
-#include "rclcpp/time_source.hpp"
 #include "rclcpp/visibility_control.hpp"
 
 namespace rclcpp
@@ -50,9 +50,13 @@ public:
 
   /// Get a clock which will be kept up to date by the node.
   RCLCPP_PUBLIC
-  virtual
   rclcpp::Clock::SharedPtr
-  get_clock();
+  get_clock() override;
+
+  /// Get a clock which will be kept up to date by the node.
+  RCLCPP_PUBLIC
+  rclcpp::Clock::ConstSharedPtr
+  get_clock() const override;
 
 private:
   RCLCPP_DISABLE_COPY(NodeClock)

rclcpp/include/rclcpp/node_interfaces/node_clock_interface.hpp

@@ -15,7 +15,6 @@
 #ifndef RCLCPP__NODE_INTERFACES__NODE_CLOCK_INTERFACE_HPP_
 #define RCLCPP__NODE_INTERFACES__NODE_CLOCK_INTERFACE_HPP_
 
-#include "rclcpp/callback_group.hpp"
 #include "rclcpp/clock.hpp"
 #include "rclcpp/macros.hpp"
 #include "rclcpp/visibility_control.hpp"
@@ -40,6 +39,12 @@ public:
   virtual
   rclcpp::Clock::SharedPtr
   get_clock() = 0;
+
+  /// Get a const ROS clock which will be kept up to date by the node.
+  RCLCPP_PUBLIC
+  virtual
+  rclcpp::Clock::ConstSharedPtr
+  get_clock() const = 0;
 };
 
 }  // namespace node_interfaces

rclcpp/include/rclcpp/node_interfaces/node_graph.hpp

@@ -30,6 +30,7 @@
 #include "rclcpp/node_interfaces/node_base_interface.hpp"
 #include "rclcpp/node_interfaces/node_graph_interface.hpp"
 #include "rclcpp/visibility_control.hpp"
+#include "rmw/topic_endpoint_info_array.h"
 
 namespace rclcpp
 {
@@ -56,66 +57,72 @@ public:
   ~NodeGraph();
 
   RCLCPP_PUBLIC
-  virtual
   std::map<std::string, std::vector<std::string>>
-  get_topic_names_and_types(bool no_demangle = false) const;
+  get_topic_names_and_types(bool no_demangle = false) const override;
 
   RCLCPP_PUBLIC
-  virtual
   std::map<std::string, std::vector<std::string>>
-  get_service_names_and_types() const;
+  get_service_names_and_types() const override;
+
+  RCLCPP_PUBLIC
+  std::map<std::string, std::vector<std::string>>
+  get_service_names_and_types_by_node(
+    const std::string & node_name,
+    const std::string & namespace_) const override;
 
   RCLCPP_PUBLIC
-  virtual
   std::vector<std::string>
-  get_node_names() const;
+  get_node_names() const override;
 
   RCLCPP_PUBLIC
-  virtual
   std::vector<std::pair<std::string, std::string>>
-  get_node_names_and_namespaces() const;
+  get_node_names_and_namespaces() const override;
 
   RCLCPP_PUBLIC
-  virtual
   size_t
-  count_publishers(const std::string & topic_name) const;
+  count_publishers(const std::string & topic_name) const override;
 
   RCLCPP_PUBLIC
-  virtual
   size_t
-  count_subscribers(const std::string & topic_name) const;
+  count_subscribers(const std::string & topic_name) const override;
 
   RCLCPP_PUBLIC
-  virtual
   const rcl_guard_condition_t *
-  get_graph_guard_condition() const;
+  get_graph_guard_condition() const override;
 
   RCLCPP_PUBLIC
-  virtual
   void
-  notify_graph_change();
+  notify_graph_change() override;
 
   RCLCPP_PUBLIC
-  virtual
   void
-  notify_shutdown();
+  notify_shutdown() override;
 
   RCLCPP_PUBLIC
-  virtual
   rclcpp::Event::SharedPtr
-  get_graph_event();
+  get_graph_event() override;
 
   RCLCPP_PUBLIC
-  virtual
   void
   wait_for_graph_change(
     rclcpp::Event::SharedPtr event,
-    std::chrono::nanoseconds timeout);
+    std::chrono::nanoseconds timeout) override;
 
   RCLCPP_PUBLIC
-  virtual
   size_t
-  count_graph_users();
+  count_graph_users() override;
+
+  RCLCPP_PUBLIC
+  std::vector<rclcpp::TopicEndpointInfo>
+  get_publishers_info_by_topic(
+    const std::string & topic_name,
+    bool no_mangle = false) const override;
+
+  RCLCPP_PUBLIC
+  std::vector<rclcpp::TopicEndpointInfo>
+  get_subscriptions_info_by_topic(
+    const std::string & topic_name,
+    bool no_mangle = false) const override;
 
 private:
   RCLCPP_DISABLE_COPY(NodeGraph)

rclcpp/include/rclcpp/node_interfaces/node_graph_interface.hpp

@@ -15,20 +15,120 @@
 #ifndef RCLCPP__NODE_INTERFACES__NODE_GRAPH_INTERFACE_HPP_
 #define RCLCPP__NODE_INTERFACES__NODE_GRAPH_INTERFACE_HPP_
 
+#include <algorithm>
+#include <array>
 #include <chrono>
 #include <map>
 #include <string>
 #include <utility>
 #include <vector>
 
+#include "rcl/graph.h"
 #include "rcl/guard_condition.h"
 
 #include "rclcpp/event.hpp"
 #include "rclcpp/macros.hpp"
+#include "rclcpp/qos.hpp"
 #include "rclcpp/visibility_control.hpp"
 
 namespace rclcpp
 {
+
+enum class EndpointType
+{
+  Invalid = RMW_ENDPOINT_INVALID,
+  Publisher = RMW_ENDPOINT_PUBLISHER,
+  Subscription = RMW_ENDPOINT_SUBSCRIPTION
+};
+
+/**
+ * Struct that contains topic endpoint information like the associated node name, node namespace,
+ * topic type, endpoint type, endpoint GID, and its QoS.
+ */
+class TopicEndpointInfo
+{
+public:
+  /// Construct a TopicEndpointInfo from a rcl_topic_endpoint_info_t.
+  RCLCPP_PUBLIC
+  explicit TopicEndpointInfo(const rcl_topic_endpoint_info_t & info)
+  : node_name_(info.node_name),
+    node_namespace_(info.node_namespace),
+    topic_type_(info.topic_type),
+    endpoint_type_(static_cast<rclcpp::EndpointType>(info.endpoint_type)),
+    qos_profile_({info.qos_profile.history, info.qos_profile.depth}, info.qos_profile)
+  {
+    std::copy(info.endpoint_gid, info.endpoint_gid + RMW_GID_STORAGE_SIZE, endpoint_gid_.begin());
+  }
+
+  /// Get a mutable reference to the node name.
+  RCLCPP_PUBLIC
+  std::string &
+  node_name();
+
+  /// Get a const reference to the node name.
+  RCLCPP_PUBLIC
+  const std::string &
+  node_name() const;
+
+  /// Get a mutable reference to the node namespace.
+  RCLCPP_PUBLIC
+  std::string &
+  node_namespace();
+
+  /// Get a const reference to the node namespace.
+  RCLCPP_PUBLIC
+  const std::string &
+  node_namespace() const;
+
+  /// Get a mutable reference to the topic type string.
+  RCLCPP_PUBLIC
+  std::string &
+  topic_type();
+
+  /// Get a const reference to the topic type string.
+  RCLCPP_PUBLIC
+  const std::string &
+  topic_type() const;
+
+  /// Get a mutable reference to the topic endpoint type.
+  RCLCPP_PUBLIC
+  rclcpp::EndpointType &
+  endpoint_type();
+
+  /// Get a const reference to the topic endpoint type.
+  RCLCPP_PUBLIC
+  const rclcpp::EndpointType &
+  endpoint_type() const;
+
+  /// Get a mutable reference to the GID of the topic endpoint.
+  RCLCPP_PUBLIC
+  std::array<uint8_t, RMW_GID_STORAGE_SIZE> &
+  endpoint_gid();
+
+  /// Get a const reference to the GID of the topic endpoint.
+  RCLCPP_PUBLIC
+  const std::array<uint8_t, RMW_GID_STORAGE_SIZE> &
+  endpoint_gid() const;
+
+  /// Get a mutable reference to the QoS profile of the topic endpoint.
+  RCLCPP_PUBLIC
+  rclcpp::QoS &
+  qos_profile();
+
+  /// Get a const reference to the QoS profile of the topic endpoint.
+  RCLCPP_PUBLIC
+  const rclcpp::QoS &
+  qos_profile() const;
+
+private:
+  std::string node_name_;
+  std::string node_namespace_;
+  std::string topic_type_;
+  rclcpp::EndpointType endpoint_type_;
+  std::array<uint8_t, RMW_GID_STORAGE_SIZE> endpoint_gid_;
+  rclcpp::QoS qos_profile_;
+};
+
 namespace node_interfaces
 {
 
@@ -65,6 +165,20 @@ public:
   std::map<std::string, std::vector<std::string>>
   get_service_names_and_types() const = 0;
 
+  /// Return a map of existing service names to list of service types for a specific node.
+  /**
+   * This function only considers services - not clients.
+   *
+   * \param[in] node_name name of the node
+   * \param[in] namespace_ namespace of the node
+   */
+  RCLCPP_PUBLIC
+  virtual
+  std::map<std::string, std::vector<std::string>>
+  get_service_names_and_types_by_node(
+    const std::string & node_name,
+    const std::string & namespace_) const = 0;
+
   /// Return a vector of existing node names (string).
   RCLCPP_PUBLIC
   virtual
@@ -150,6 +264,24 @@ public:
   virtual
   size_t
   count_graph_users() = 0;
+
+  /// Return the topic endpoint information about publishers on a given topic.
+  /**
+   * \sa rclcpp::Node::get_publishers_info_by_topic
+   */
+  RCLCPP_PUBLIC
+  virtual
+  std::vector<rclcpp::TopicEndpointInfo>
+  get_publishers_info_by_topic(const std::string & topic_name, bool no_mangle = false) const = 0;
+
+  /// Return the topic endpoint information about subscriptions on a given topic.
+  /**
+   * \sa rclcpp::Node::get_subscriptions_info_by_topic
+   */
+  RCLCPP_PUBLIC
+  virtual
+  std::vector<rclcpp::TopicEndpointInfo>
+  get_subscriptions_info_by_topic(const std::string & topic_name, bool no_mangle = false) const = 0;
 };
 
 }  // namespace node_interfaces

rclcpp/include/rclcpp/node_interfaces/node_logging.hpp

@@ -42,14 +42,12 @@ public:
   ~NodeLogging();
 
   RCLCPP_PUBLIC
-  virtual
   rclcpp::Logger
-  get_logger() const;
+  get_logger() const override;
 
   RCLCPP_PUBLIC
-  virtual
   const char *
-  get_logger_name() const;
+  get_logger_name() const override;
 
 private:
   RCLCPP_DISABLE_COPY(NodeLogging)

rclcpp/include/rclcpp/node_interfaces/node_logging_interface.hpp

@@ -19,7 +19,6 @@
 
 #include "rclcpp/logger.hpp"
 #include "rclcpp/macros.hpp"
-#include "rclcpp/node_interfaces/node_base_interface.hpp"
 #include "rclcpp/visibility_control.hpp"
 
 namespace rclcpp

rclcpp/include/rclcpp/node_interfaces/node_parameters.hpp

@@ -21,6 +21,8 @@
 #include <string>
 #include <vector>
 
+#include "rcutils/macros.h"
+
 #include "rcl_interfaces/msg/list_parameters_result.hpp"
 #include "rcl_interfaces/msg/parameter_descriptor.hpp"
 #include "rcl_interfaces/msg/parameter_event.hpp"
@@ -28,6 +30,7 @@
 
 #include "rclcpp/macros.hpp"
 #include "rclcpp/node_interfaces/node_base_interface.hpp"
+#include "rclcpp/node_interfaces/node_logging_interface.hpp"
 #include "rclcpp/node_interfaces/node_parameters_interface.hpp"
 #include "rclcpp/node_interfaces/node_services_interface.hpp"
 #include "rclcpp/node_interfaces/node_topics_interface.hpp"
@@ -159,6 +162,7 @@ public:
   list_parameters(const std::vector<std::string> & prefixes, uint64_t depth) const override;
 
   RCLCPP_PUBLIC
+  RCUTILS_WARN_UNUSED
   OnSetParametersCallbackHandle::SharedPtr
   add_on_set_parameters_callback(OnParametersSetCallbackType callback) override;
 
@@ -166,6 +170,7 @@ public:
   void
   remove_on_set_parameters_callback(const OnSetParametersCallbackHandle * const handler) override;
 
+  [[deprecated("use add_on_set_parameters_callback(OnParametersSetCallbackType callback) instead")]]
   RCLCPP_PUBLIC
   OnParametersSetCallbackType
   set_on_parameters_set_callback(OnParametersSetCallbackType callback) override;

rclcpp/include/rclcpp/node_interfaces/node_parameters_interface.hpp

@@ -193,8 +193,10 @@ public:
 
   /// Register a callback for when parameters are being set, return an existing one.
   /**
+   * \deprecated Use add_on_set_parameters_callback instead.
    * \sa rclcpp::Node::set_on_parameters_set_callback
    */
+  [[deprecated("use add_on_set_parameters_callback(OnParametersSetCallbackType callback) instead")]]
   RCLCPP_PUBLIC
   virtual
   OnParametersSetCallbackType

rclcpp/include/rclcpp/node_interfaces/node_services.hpp

@@ -42,18 +42,16 @@ public:
   ~NodeServices();
 
   RCLCPP_PUBLIC
-  virtual
   void
   add_client(
     rclcpp::ClientBase::SharedPtr client_base_ptr,
-    rclcpp::callback_group::CallbackGroup::SharedPtr group);
+    rclcpp::CallbackGroup::SharedPtr group) override;
 
   RCLCPP_PUBLIC
-  virtual
   void
   add_service(
     rclcpp::ServiceBase::SharedPtr service_base_ptr,
-    rclcpp::callback_group::CallbackGroup::SharedPtr group);
+    rclcpp::CallbackGroup::SharedPtr group) override;
 
 private:
   RCLCPP_DISABLE_COPY(NodeServices)

rclcpp/include/rclcpp/node_interfaces/node_services_interface.hpp

@@ -41,14 +41,14 @@ public:
   void
   add_client(
     rclcpp::ClientBase::SharedPtr client_base_ptr,
-    rclcpp::callback_group::CallbackGroup::SharedPtr group) = 0;
+    rclcpp::CallbackGroup::SharedPtr group) = 0;
 
   RCLCPP_PUBLIC
   virtual
   void
   add_service(
     rclcpp::ServiceBase::SharedPtr service_base_ptr,
-    rclcpp::callback_group::CallbackGroup::SharedPtr group) = 0;
+    rclcpp::CallbackGroup::SharedPtr group) = 0;
 };
 
 }  // namespace node_interfaces

rclcpp/include/rclcpp/node_interfaces/node_time_source.hpp

@@ -15,12 +15,13 @@
 #ifndef RCLCPP__NODE_INTERFACES__NODE_TIME_SOURCE_HPP_
 #define RCLCPP__NODE_INTERFACES__NODE_TIME_SOURCE_HPP_
 
-#include "rclcpp/callback_group.hpp"
-#include "rclcpp/clock.hpp"
 #include "rclcpp/macros.hpp"
 #include "rclcpp/node_interfaces/node_base_interface.hpp"
 #include "rclcpp/node_interfaces/node_clock_interface.hpp"
+#include "rclcpp/node_interfaces/node_graph_interface.hpp"
+#include "rclcpp/node_interfaces/node_logging_interface.hpp"
 #include "rclcpp/node_interfaces/node_parameters_interface.hpp"
+#include "rclcpp/node_interfaces/node_services_interface.hpp"
 #include "rclcpp/node_interfaces/node_time_source_interface.hpp"
 #include "rclcpp/node_interfaces/node_topics_interface.hpp"
 #include "rclcpp/time_source.hpp"

rclcpp/include/rclcpp/node_interfaces/node_time_source_interface.hpp

@@ -15,8 +15,6 @@
 #ifndef RCLCPP__NODE_INTERFACES__NODE_TIME_SOURCE_INTERFACE_HPP_
 #define RCLCPP__NODE_INTERFACES__NODE_TIME_SOURCE_INTERFACE_HPP_
 
-#include "rclcpp/callback_group.hpp"
-#include "rclcpp/clock.hpp"
 #include "rclcpp/macros.hpp"
 #include "rclcpp/visibility_control.hpp"
 

rclcpp/include/rclcpp/node_interfaces/node_timers.hpp

@@ -42,11 +42,10 @@ public:
 
   /// Add a timer to the node.
   RCLCPP_PUBLIC
-  virtual
   void
   add_timer(
     rclcpp::TimerBase::SharedPtr timer,
-    rclcpp::callback_group::CallbackGroup::SharedPtr callback_group);
+    rclcpp::CallbackGroup::SharedPtr callback_group) override;
 
 private:
   RCLCPP_DISABLE_COPY(NodeTimers)

rclcpp/include/rclcpp/node_interfaces/node_timers_interface.hpp

@@ -41,7 +41,7 @@ public:
   void
   add_timer(
     rclcpp::TimerBase::SharedPtr timer,
-    rclcpp::callback_group::CallbackGroup::SharedPtr callback_group) = 0;
+    rclcpp::CallbackGroup::SharedPtr callback_group) = 0;
 };
 
 }  // namespace node_interfaces

rclcpp/include/rclcpp/node_interfaces/node_topics.hpp

@@ -22,6 +22,7 @@
 
 #include "rclcpp/macros.hpp"
 #include "rclcpp/node_interfaces/node_base_interface.hpp"
+#include "rclcpp/node_interfaces/node_timers_interface.hpp"
 #include "rclcpp/node_interfaces/node_topics_interface.hpp"
 #include "rclcpp/publisher.hpp"
 #include "rclcpp/publisher_factory.hpp"
@@ -39,7 +40,9 @@ public:
   RCLCPP_SMART_PTR_ALIASES_ONLY(NodeTopicsInterface)
 
   RCLCPP_PUBLIC
-  explicit NodeTopics(rclcpp::node_interfaces::NodeBaseInterface * node_base);
+  NodeTopics(
+    rclcpp::node_interfaces::NodeBaseInterface * node_base,
+    rclcpp::node_interfaces::NodeTimersInterface * node_timers);
 
   RCLCPP_PUBLIC
   ~NodeTopics() override;
@@ -55,7 +58,7 @@ public:
   void
   add_publisher(
     rclcpp::PublisherBase::SharedPtr publisher,
-    rclcpp::callback_group::CallbackGroup::SharedPtr callback_group) override;
+    rclcpp::CallbackGroup::SharedPtr callback_group) override;
 
   RCLCPP_PUBLIC
   rclcpp::SubscriptionBase::SharedPtr
@@ -68,16 +71,21 @@ public:
   void
   add_subscription(
     rclcpp::SubscriptionBase::SharedPtr subscription,
-    rclcpp::callback_group::CallbackGroup::SharedPtr callback_group) override;
+    rclcpp::CallbackGroup::SharedPtr callback_group) override;
 
   RCLCPP_PUBLIC
   rclcpp::node_interfaces::NodeBaseInterface *
   get_node_base_interface() const override;
 
+  RCLCPP_PUBLIC
+  rclcpp::node_interfaces::NodeTimersInterface *
+  get_node_timers_interface() const override;
+
 private:
   RCLCPP_DISABLE_COPY(NodeTopics)
 
   rclcpp::node_interfaces::NodeBaseInterface * node_base_;
+  rclcpp::node_interfaces::NodeTimersInterface * node_timers_;
 };
 
 }  // namespace node_interfaces

rclcpp/include/rclcpp/node_interfaces/node_topics_interface.hpp

@@ -22,7 +22,10 @@
 #include "rcl/publisher.h"
 #include "rcl/subscription.h"
 
+#include "rclcpp/callback_group.hpp"
 #include "rclcpp/macros.hpp"
+#include "rclcpp/node_interfaces/node_base_interface.hpp"
+#include "rclcpp/node_interfaces/node_timers_interface.hpp"
 #include "rclcpp/publisher.hpp"
 #include "rclcpp/publisher_factory.hpp"
 #include "rclcpp/subscription.hpp"
@@ -57,7 +60,7 @@ public:
   void
   add_publisher(
     rclcpp::PublisherBase::SharedPtr publisher,
-    rclcpp::callback_group::CallbackGroup::SharedPtr callback_group) = 0;
+    rclcpp::CallbackGroup::SharedPtr callback_group) = 0;
 
   RCLCPP_PUBLIC
   virtual
@@ -72,12 +75,17 @@ public:
   void
   add_subscription(
     rclcpp::SubscriptionBase::SharedPtr subscription,
-    rclcpp::callback_group::CallbackGroup::SharedPtr callback_group) = 0;
+    rclcpp::CallbackGroup::SharedPtr callback_group) = 0;
 
   RCLCPP_PUBLIC
   virtual
   rclcpp::node_interfaces::NodeBaseInterface *
   get_node_base_interface() const = 0;
+
+  RCLCPP_PUBLIC
+  virtual
+  rclcpp::node_interfaces::NodeTimersInterface *
+  get_node_timers_interface() const = 0;
 };
 
 }  // namespace node_interfaces

rclcpp/include/rclcpp/node_interfaces/node_waitables.hpp

@@ -16,7 +16,6 @@
 #define RCLCPP__NODE_INTERFACES__NODE_WAITABLES_HPP_
 
 #include "rclcpp/callback_group.hpp"
-#include "rclcpp/client.hpp"
 #include "rclcpp/macros.hpp"
 #include "rclcpp/node_interfaces/node_base_interface.hpp"
 #include "rclcpp/node_interfaces/node_waitables_interface.hpp"
@@ -42,18 +41,16 @@ public:
   ~NodeWaitables();
 
   RCLCPP_PUBLIC
-  virtual
   void
   add_waitable(
     rclcpp::Waitable::SharedPtr waitable_base_ptr,
-    rclcpp::callback_group::CallbackGroup::SharedPtr group);
+    rclcpp::CallbackGroup::SharedPtr group) override;
 
   RCLCPP_PUBLIC
-  virtual
   void
   remove_waitable(
     rclcpp::Waitable::SharedPtr waitable_ptr,
-    rclcpp::callback_group::CallbackGroup::SharedPtr group) noexcept;
+    rclcpp::CallbackGroup::SharedPtr group) noexcept override;
 
 private:
   RCLCPP_DISABLE_COPY(NodeWaitables)

rclcpp/include/rclcpp/node_interfaces/node_waitables_interface.hpp

@@ -40,7 +40,7 @@ public:
   void
   add_waitable(
     rclcpp::Waitable::SharedPtr waitable_ptr,
-    rclcpp::callback_group::CallbackGroup::SharedPtr group) = 0;
+    rclcpp::CallbackGroup::SharedPtr group) = 0;
 
   /// \note this function should not throw because it may be called in destructors
   RCLCPP_PUBLIC
@@ -48,7 +48,7 @@ public:
   void
   remove_waitable(
     rclcpp::Waitable::SharedPtr waitable_ptr,
-    rclcpp::callback_group::CallbackGroup::SharedPtr group) noexcept = 0;
+    rclcpp::CallbackGroup::SharedPtr group) noexcept = 0;
 };
 
 }  // namespace node_interfaces

rclcpp/include/rclcpp/node_options.hpp

@@ -38,11 +38,12 @@ public:
   /**
    * Default values for the node options:
    *
-   *   - context = rclcpp::contexts::default_context::get_global_default_context()
+   *   - context = rclcpp::contexts::get_global_default_context()
    *   - arguments = {}
    *   - parameter_overrides = {}
    *   - use_global_arguments = true
    *   - use_intra_process_comms = false
+   *   - enable_topic_statistics = false
    *   - start_parameter_services = true
    *   - start_parameter_event_publisher = true
    *   - parameter_event_qos = rclcpp::ParameterEventQoS
@@ -76,6 +77,9 @@ public:
    * This data structure is created lazily, on the first call to this function.
    * Repeated calls will not regenerate it unless one of the input settings
    * changed, like arguments, use_global_arguments, or the rcl allocator.
+   *
+   * \return a const rcl_node_options_t structure used by the node
+   * \throws exceptions::UnknownROSArgsError if there are unknown ROS arguments
    */
   RCLCPP_PUBLIC
   const rcl_node_options_t *
@@ -152,6 +156,22 @@ public:
   NodeOptions &
   use_global_arguments(bool use_global_arguments);
 
+  /// Return the enable_rosout flag.
+  RCLCPP_PUBLIC
+  bool
+  enable_rosout() const;
+
+  /// Set the enable_rosout flag, return this for parameter idiom.
+  /**
+   * If false this will cause the node not to use rosout logging.
+   *
+   * Defaults to true for now, as there are still some cases where it is
+   * desirable.
+   */
+  RCLCPP_PUBLIC
+  NodeOptions &
+  enable_rosout(bool enable_rosout);
+
   /// Return the use_intra_process_comms flag.
   RCLCPP_PUBLIC
   bool
@@ -171,6 +191,23 @@ public:
   NodeOptions &
   use_intra_process_comms(bool use_intra_process_comms);
 
+  /// Return the enable_topic_statistics flag.
+  RCLCPP_PUBLIC
+  bool
+  enable_topic_statistics() const;
+
+  /// Set the enable_topic_statistics flag, return this for parameter idiom.
+  /**
+   * If true, topic statistics collection and publication will be enabled
+   * for all subscriptions.
+   * This can be used to override the global topic statistics setting.
+   *
+   * Defaults to false.
+   */
+  RCLCPP_PUBLIC
+  NodeOptions &
+  enable_topic_statistics(bool enable_topic_statistics);
+
   /// Return the start_parameter_services flag.
   RCLCPP_PUBLIC
   bool
@@ -304,7 +341,7 @@ private:
   // documentation in this class.
 
   rclcpp::Context::SharedPtr context_ {
-    rclcpp::contexts::default_context::get_global_default_context()};
+    rclcpp::contexts::get_global_default_context()};
 
   std::vector<std::string> arguments_ {};
 
@@ -312,8 +349,12 @@ private:
 
   bool use_global_arguments_ {true};
 
+  bool enable_rosout_ {true};
+
   bool use_intra_process_comms_ {false};
 
+  bool enable_topic_statistics_ {false};
+
   bool start_parameter_services_ {true};
 
   bool start_parameter_event_publisher_ {true};

rclcpp/include/rclcpp/parameter.hpp

@@ -22,6 +22,7 @@
 #include <vector>
 
 #include "rcl_interfaces/msg/parameter.hpp"
+#include "rclcpp/exceptions.hpp"
 #include "rclcpp/parameter_value.hpp"
 #include "rclcpp/visibility_control.hpp"
 
@@ -82,18 +83,22 @@ public:
   bool
   operator!=(const Parameter & rhs) const;
 
+  /// Get the type of the parameter
   RCLCPP_PUBLIC
   ParameterType
   get_type() const;
 
+  /// Get the type name of the parameter
   RCLCPP_PUBLIC
   std::string
   get_type_name() const;
 
+  /// Get the name of the parameter
   RCLCPP_PUBLIC
   const std::string &
   get_name() const;
 
+  /// Get value of parameter as a parameter message.
   RCLCPP_PUBLIC
   rcl_interfaces::msg::ParameterValue
   get_value_message() const;
@@ -104,6 +109,9 @@ public:
   get_parameter_value() const;
 
   /// Get value of parameter using rclcpp::ParameterType as template argument.
+  /**
+   * \throws rclcpp::exceptions::InvalidParameterTypeException if the type doesn't match
+   */
   template<ParameterType ParamT>
   decltype(auto)
   get_value() const
@@ -116,50 +124,89 @@ public:
   decltype(auto)
   get_value() const;
 
+  /// Get value of parameter as boolean.
+  /**
+   * \throws rclcpp::ParameterTypeException if the type doesn't match
+   */
   RCLCPP_PUBLIC
   bool
   as_bool() const;
 
+  /// Get value of parameter as integer.
+  /**
+   * \throws rclcpp::ParameterTypeException if the type doesn't match
+   */
   RCLCPP_PUBLIC
   int64_t
   as_int() const;
 
+  /// Get value of parameter as double.
+  /**
+   * \throws rclcpp::ParameterTypeException if the type doesn't match
+   */
   RCLCPP_PUBLIC
   double
   as_double() const;
 
+  /// Get value of parameter as string.
+  /**
+   * \throws rclcpp::ParameterTypeException if the type doesn't match
+   */
   RCLCPP_PUBLIC
   const std::string &
   as_string() const;
 
+  /// Get value of parameter as byte array (vector<uint8_t>).
+  /**
+   * \throws rclcpp::ParameterTypeException if the type doesn't match
+   */
   RCLCPP_PUBLIC
   const std::vector<uint8_t> &
   as_byte_array() const;
 
+  /// Get value of parameter as bool array (vector<bool>).
+  /**
+   * \throws rclcpp::ParameterTypeException if the type doesn't match
+   */
   RCLCPP_PUBLIC
   const std::vector<bool> &
   as_bool_array() const;
 
+  /// Get value of parameter as integer array (vector<int64_t>).
+  /**
+   * \throws rclcpp::ParameterTypeException if the type doesn't match
+   */
   RCLCPP_PUBLIC
   const std::vector<int64_t> &
   as_integer_array() const;
 
+  /// Get value of parameter as double array (vector<double>).
+  /**
+   * \throws rclcpp::ParameterTypeException if the type doesn't match
+   */
   RCLCPP_PUBLIC
   const std::vector<double> &
   as_double_array() const;
 
+  /// Get value of parameter as string array (vector<std::string>).
+  /**
+   * \throws rclcpp::ParameterTypeException if the type doesn't match
+   */
   RCLCPP_PUBLIC
   const std::vector<std::string> &
   as_string_array() const;
 
+  /// Convert a parameter message in a Parameter class object.
   RCLCPP_PUBLIC
   static Parameter
   from_parameter_msg(const rcl_interfaces::msg::Parameter & parameter);
 
+  /// Convert the class in a parameter message.
   RCLCPP_PUBLIC
   rcl_interfaces::msg::Parameter
   to_parameter_msg() const;
 
+  /// Get value of parameter as a string.
   RCLCPP_PUBLIC
   std::string
   value_to_string() const;
@@ -221,8 +268,12 @@ template<typename T>
 decltype(auto)
 Parameter::get_value() const
 {
-  // use the helper to specialize for the ParameterValue and Parameter cases.
-  return detail::get_value_helper<T>(this);
+  try {
+    // use the helper to specialize for the ParameterValue and Parameter cases.
+    return detail::get_value_helper<T>(this);
+  } catch (const ParameterTypeException & ex) {
+    throw exceptions::InvalidParameterTypeException(this->name_, ex.what());
+  }
 }
 
 }  // namespace rclcpp

rclcpp/include/rclcpp/parameter_client.hpp

@@ -46,6 +46,16 @@ class AsyncParametersClient
 public:
   RCLCPP_SMART_PTR_DEFINITIONS(AsyncParametersClient)
 
+  /// Create an async parameters client.
+  /**
+   * \param[in] node_base_interface The node base interface of the corresponding node.
+   * \param[in] node_topics_interface Node topic base interface.
+   * \param[in] node_graph_interface The node graph interface of the corresponding node.
+   * \param[in] node_services_interface Node service interface.
+   * \param[in] remote_node_name (optional) name of the remote node
+   * \param[in] qos_profile (optional) The rmw qos profile to use to subscribe
+   * \param[in] group (optional) The async parameter client will be added to this callback group.
+   */
   RCLCPP_PUBLIC
   AsyncParametersClient(
     const rclcpp::node_interfaces::NodeBaseInterface::SharedPtr node_base_interface,
@@ -54,21 +64,35 @@ public:
     const rclcpp::node_interfaces::NodeServicesInterface::SharedPtr node_services_interface,
     const std::string & remote_node_name = "",
     const rmw_qos_profile_t & qos_profile = rmw_qos_profile_parameters,
-    rclcpp::callback_group::CallbackGroup::SharedPtr group = nullptr);
+    rclcpp::CallbackGroup::SharedPtr group = nullptr);
 
+  /// Constructor
+  /**
+   * \param[in] node The async paramters client will be added to this node.
+   * \param[in] remote_node_name (optional) name of the remote node
+   * \param[in] qos_profile (optional) The rmw qos profile to use to subscribe
+   * \param[in] group (optional) The async parameter client will be added to this callback group.
+   */
   RCLCPP_PUBLIC
   AsyncParametersClient(
     const rclcpp::Node::SharedPtr node,
     const std::string & remote_node_name = "",
     const rmw_qos_profile_t & qos_profile = rmw_qos_profile_parameters,
-    rclcpp::callback_group::CallbackGroup::SharedPtr group = nullptr);
+    rclcpp::CallbackGroup::SharedPtr group = nullptr);
 
+  /// Constructor
+  /**
+   * \param[in] node The  async paramters client will be added to this node.
+   * \param[in] remote_node_name (optional) name of the remote node
+   * \param[in] qos_profile (optional) The rmw qos profile to use to subscribe
+   * \param[in] group (optional) The async parameter client will be added to this callback group.
+   */
   RCLCPP_PUBLIC
   AsyncParametersClient(
     rclcpp::Node * node,
     const std::string & remote_node_name = "",
     const rmw_qos_profile_t & qos_profile = rmw_qos_profile_parameters,
-    rclcpp::callback_group::CallbackGroup::SharedPtr group = nullptr);
+    rclcpp::CallbackGroup::SharedPtr group = nullptr);
 
   RCLCPP_PUBLIC
   std::shared_future<std::vector<rclcpp::Parameter>>
@@ -153,16 +177,32 @@ public:
   {
     return rclcpp::create_subscription<rcl_interfaces::msg::ParameterEvent>(
       node,
-      "parameter_events",
+      "/parameter_events",
       qos,
       std::forward<CallbackT>(callback),
       options);
   }
 
+  /// Return if the parameter services are ready.
+  /**
+   * This method checks the following services:
+   *  - get parameter
+   *  - get parameter
+   *  - set parameters
+   *  - list parameters
+   *  - describe parameters
+   *
+   * \return `true` if the service is ready, `false` otherwise
+   */
   RCLCPP_PUBLIC
   bool
   service_is_ready() const;
 
+  /// Wait for the services to be ready.
+  /**
+   * \param timeout maximum time to wait
+   * \return `true` if the services are ready and the timeout is not over, `false` otherwise
+   */
   template<typename RepT = int64_t, typename RatioT = std::milli>
   bool
   wait_for_service(
@@ -205,7 +245,7 @@ public:
 
   RCLCPP_PUBLIC
   SyncParametersClient(
-    rclcpp::executor::Executor::SharedPtr executor,
+    rclcpp::Executor::SharedPtr executor,
     rclcpp::Node::SharedPtr node,
     const std::string & remote_node_name = "",
     const rmw_qos_profile_t & qos_profile = rmw_qos_profile_parameters);
@@ -218,14 +258,14 @@ public:
 
   RCLCPP_PUBLIC
   SyncParametersClient(
-    rclcpp::executor::Executor::SharedPtr executor,
+    rclcpp::Executor::SharedPtr executor,
     rclcpp::Node * node,
     const std::string & remote_node_name = "",
     const rmw_qos_profile_t & qos_profile = rmw_qos_profile_parameters);
 
   RCLCPP_PUBLIC
   SyncParametersClient(
-    rclcpp::executor::Executor::SharedPtr executor,
+    rclcpp::Executor::SharedPtr executor,
     const rclcpp::node_interfaces::NodeBaseInterface::SharedPtr node_base_interface,
     const rclcpp::node_interfaces::NodeTopicsInterface::SharedPtr node_topics_interface,
     const rclcpp::node_interfaces::NodeGraphInterface::SharedPtr node_graph_interface,
@@ -271,10 +311,11 @@ public:
   {
     return get_parameter_impl(
       parameter_name,
-      std::function<T()>([&parameter_name]() -> T
-      {
-        throw std::runtime_error("Parameter '" + parameter_name + "' is not set");
-      })
+      std::function<T()>(
+        [&parameter_name]() -> T
+        {
+          throw std::runtime_error("Parameter '" + parameter_name + "' is not set");
+        })
     );
   }
 
@@ -338,7 +379,7 @@ public:
   }
 
 private:
-  rclcpp::executor::Executor::SharedPtr executor_;
+  rclcpp::Executor::SharedPtr executor_;
   const rclcpp::node_interfaces::NodeBaseInterface::SharedPtr node_base_interface_;
   AsyncParametersClient::SharedPtr async_parameters_client_;
 };

rclcpp/include/rclcpp/publisher.hpp

@@ -59,6 +59,17 @@ public:
 
   RCLCPP_SMART_PTR_DEFINITIONS(Publisher<MessageT, AllocatorT>)
 
+  /// Default constructor.
+  /**
+   * The constructor for a Publisher is almost never called directly.
+   * Instead, subscriptions should be instantiated through the function
+   * rclcpp::create_publisher().
+   *
+   * \param[in] node_base NodeBaseInterface pointer that is used in part of the setup.
+   * \param[in] topic Name of the topic to publish to.
+   * \param[in] qos QoS profile for Subcription.
+   * \param[in] options options for the subscription.
+   */
   Publisher(
     rclcpp::node_interfaces::NodeBaseInterface * node_base,
     const std::string & topic,
@@ -84,7 +95,22 @@ public:
         options_.event_callbacks.liveliness_callback,
         RCL_PUBLISHER_LIVELINESS_LOST);
     }
-
+    if (options_.event_callbacks.incompatible_qos_callback) {
+      this->add_event_handler(
+        options_.event_callbacks.incompatible_qos_callback,
+        RCL_PUBLISHER_OFFERED_INCOMPATIBLE_QOS);
+    } else if (options_.use_default_callbacks) {
+      // Register default callback when not specified
+      try {
+        this->add_event_handler(
+          [this](QOSOfferedIncompatibleQoSInfo & info) {
+            this->default_incompatible_qos_callback(info);
+          },
+          RCL_PUBLISHER_OFFERED_INCOMPATIBLE_QOS);
+      } catch (UnsupportedEventTypeException & /*exc*/) {
+        // pass
+      }
+    }
     // Setup continues in the post construction method, post_init_setup().
   }
 
@@ -202,6 +228,12 @@ public:
     return this->do_serialized_publish(&serialized_msg);
   }
 
+  void
+  publish(const SerializedMessage & serialized_msg)
+  {
+    return this->do_serialized_publish(&serialized_msg.get_rcl_serialized_message());
+  }
+
   /// Publish an instance of a LoanedMessage.
   /**
    * When publishing a loaned message, the memory for this ROS message will be deallocated
@@ -247,12 +279,12 @@ protected:
   void
   do_inter_process_publish(const MessageT & msg)
   {
-    auto status = rcl_publish(&publisher_handle_, &msg, nullptr);
+    auto status = rcl_publish(publisher_handle_.get(), &msg, nullptr);
 
     if (RCL_RET_PUBLISHER_INVALID == status) {
       rcl_reset_error();  // next call will reset error message if not context
-      if (rcl_publisher_is_valid_except_context(&publisher_handle_)) {
-        rcl_context_t * context = rcl_publisher_get_context(&publisher_handle_);
+      if (rcl_publisher_is_valid_except_context(publisher_handle_.get())) {
+        rcl_context_t * context = rcl_publisher_get_context(publisher_handle_.get());
         if (nullptr != context && !rcl_context_is_valid(context)) {
           // publisher is invalid due to context being shutdown
           return;
@@ -271,7 +303,7 @@ protected:
       // TODO(Karsten1987): support serialized message passed by intraprocess
       throw std::runtime_error("storing serialized messages in intra process is not supported yet");
     }
-    auto status = rcl_publish_serialized_message(&publisher_handle_, serialized_msg, nullptr);
+    auto status = rcl_publish_serialized_message(publisher_handle_.get(), serialized_msg, nullptr);
     if (RCL_RET_OK != status) {
       rclcpp::exceptions::throw_from_rcl_error(status, "failed to publish serialized message");
     }
@@ -280,12 +312,12 @@ protected:
   void
   do_loaned_message_publish(MessageT * msg)
   {
-    auto status = rcl_publish_loaned_message(&publisher_handle_, msg, nullptr);
+    auto status = rcl_publish_loaned_message(publisher_handle_.get(), msg, nullptr);
 
     if (RCL_RET_PUBLISHER_INVALID == status) {
       rcl_reset_error();  // next call will reset error message if not context
-      if (rcl_publisher_is_valid_except_context(&publisher_handle_)) {
-        rcl_context_t * context = rcl_publisher_get_context(&publisher_handle_);
+      if (rcl_publisher_is_valid_except_context(publisher_handle_.get())) {
+        rcl_context_t * context = rcl_publisher_get_context(publisher_handle_.get());
         if (nullptr != context && !rcl_context_is_valid(context)) {
           // publisher is invalid due to context being shutdown
           return;

rclcpp/include/rclcpp/publisher_base.hpp

@@ -99,13 +99,13 @@ public:
   /// Get the rcl publisher handle.
   /** \return The rcl publisher handle. */
   RCLCPP_PUBLIC
-  rcl_publisher_t *
+  std::shared_ptr<rcl_publisher_t>
   get_publisher_handle();
 
   /// Get the rcl publisher handle.
   /** \return The rcl publisher handle. */
   RCLCPP_PUBLIC
-  const rcl_publisher_t *
+  std::shared_ptr<const rcl_publisher_t>
   get_publisher_handle() const;
 
   /// Get all the QoS event handlers associated with this publisher.
@@ -200,17 +200,21 @@ protected:
     const EventCallbackT & callback,
     const rcl_publisher_event_type_t event_type)
   {
-    auto handler = std::make_shared<QOSEventHandler<EventCallbackT>>(
+    auto handler = std::make_shared<QOSEventHandler<EventCallbackT,
+        std::shared_ptr<rcl_publisher_t>>>(
       callback,
       rcl_publisher_event_init,
-      &publisher_handle_,
+      publisher_handle_,
       event_type);
     event_handlers_.emplace_back(handler);
   }
 
+  RCLCPP_PUBLIC
+  void default_incompatible_qos_callback(QOSOfferedIncompatibleQoSInfo & info) const;
+
   std::shared_ptr<rcl_node_t> rcl_node_handle_;
 
-  rcl_publisher_t publisher_handle_ = rcl_get_zero_initialized_publisher();
+  std::shared_ptr<rcl_publisher_t> publisher_handle_;
 
   std::vector<std::shared_ptr<rclcpp::QOSEventHandlerBase>> event_handlers_;
 

rclcpp/include/rclcpp/publisher_options.hpp

@@ -30,10 +30,7 @@
 namespace rclcpp
 {
 
-namespace callback_group
-{
 class CallbackGroup;
-}  // namespace callback_group
 
 /// Non-templated part of PublisherOptionsWithAllocator<Allocator>.
 struct PublisherOptionsBase
@@ -44,8 +41,11 @@ struct PublisherOptionsBase
   /// Callbacks for various events related to publishers.
   PublisherEventCallbacks event_callbacks;
 
+  /// Whether or not to use default callbacks when user doesn't supply any in event_callbacks
+  bool use_default_callbacks = true;
+
   /// Callback group in which the waitable items from the publisher should be placed.
-  std::shared_ptr<rclcpp::callback_group::CallbackGroup> callback_group;
+  std::shared_ptr<rclcpp::CallbackGroup> callback_group;
 
   /// Optional RMW implementation specific payload to be used during creation of the publisher.
   std::shared_ptr<rclcpp::detail::RMWImplementationSpecificPublisherPayload>
@@ -71,11 +71,8 @@ struct PublisherOptionsWithAllocator : public PublisherOptionsBase
   rcl_publisher_options_t
   to_rcl_publisher_options(const rclcpp::QoS & qos) const
   {
-    rcl_publisher_options_t result;
-    using AllocatorTraits = std::allocator_traits<Allocator>;
-    using MessageAllocatorT = typename AllocatorTraits::template rebind_alloc<MessageT>;
-    auto message_alloc = std::make_shared<MessageAllocatorT>(*this->get_allocator().get());
-    result.allocator = rclcpp::allocator::get_rcl_allocator<MessageT>(*message_alloc);
+    rcl_publisher_options_t result = rcl_publisher_get_default_options();
+    result.allocator = this->get_rcl_allocator();
     result.qos = qos.get_rmw_qos_profile();
 
     // Apply payload to rcl_publisher_options if necessary.
@@ -92,15 +89,32 @@ struct PublisherOptionsWithAllocator : public PublisherOptionsBase
   get_allocator() const
   {
     if (!this->allocator) {
-      // TODO(wjwwood): I would like to use the commented line instead, but
-      //   cppcheck 1.89 fails with:
-      //     Syntax Error: AST broken, binary operator '>' doesn't have two operands.
-      // return std::make_shared<Allocator>();
-      std::shared_ptr<Allocator> tmp(new Allocator());
-      return tmp;
+      return std::make_shared<Allocator>();
     }
     return this->allocator;
   }
+
+private:
+  using PlainAllocator =
+    typename std::allocator_traits<Allocator>::template rebind_alloc<char>;
+
+  rcl_allocator_t
+  get_rcl_allocator() const
+  {
+    if (!plain_allocator_storage_) {
+      plain_allocator_storage_ =
+        std::make_shared<PlainAllocator>(*this->get_allocator());
+    }
+    return rclcpp::allocator::get_rcl_allocator<char>(*plain_allocator_storage_);
+  }
+
+  // This is a temporal workaround, to make sure that get_allocator()
+  // always returns a copy of the same allocator.
+  mutable std::shared_ptr<Allocator> allocator_storage_;
+
+  // This is a temporal workaround, to keep the plain allocator that backs
+  // up the rcl allocator returned in rcl_publisher_options_t alive.
+  mutable std::shared_ptr<PlainAllocator> plain_allocator_storage_;
 };
 
 using PublisherOptions = PublisherOptionsWithAllocator<std::allocator<void>>;

rclcpp/include/rclcpp/qos.hpp

@@ -15,15 +15,20 @@
 #ifndef RCLCPP__QOS_HPP_
 #define RCLCPP__QOS_HPP_
 
-#include <rmw/qos_profiles.h>
-#include <rmw/types.h>
+#include <string>
 
 #include "rclcpp/duration.hpp"
 #include "rclcpp/visibility_control.hpp"
+#include "rmw/incompatible_qos_events_statuses.h"
+#include "rmw/qos_profiles.h"
+#include "rmw/types.h"
 
 namespace rclcpp
 {
 
+RCLCPP_PUBLIC
+std::string qos_policy_name_from_kind(rmw_qos_policy_kind_t policy_kind);
+
 /// QoS initialization values, cannot be created directly, use KeepAll or KeepLast instead.
 struct RCLCPP_PUBLIC QoSInitialization
 {
@@ -151,6 +156,24 @@ private:
   rmw_qos_profile_t rmw_qos_profile_;
 };
 
+/// Check if two QoS profiles are exactly equal in all policy values.
+RCLCPP_PUBLIC
+bool operator==(const QoS & left, const QoS & right);
+RCLCPP_PUBLIC
+bool operator!=(const QoS & left, const QoS & right);
+
+/**
+ * Sensor Data QoS class
+ *    - History: Keep last,
+ *    - Depth: 5,
+ *    - Reliability: Best effort,
+ *    - Durability: Volatile,
+ *    - Deadline: Default,
+ *    - Lifespan: Default,
+ *    - Liveliness: System default,
+ *    - Liveliness lease duration: default,
+ *    - avoid ros namespace conventions: false
+ */
 class RCLCPP_PUBLIC SensorDataQoS : public QoS
 {
 public:
@@ -161,6 +184,18 @@ public:
   ));
 };
 
+/**
+ * Parameters QoS class
+ *    - History: Keep last,
+ *    - Depth: 1000,
+ *    - Reliability: Reliable,
+ *    - Durability: Volatile,
+ *    - Deadline: Default,
+ *    - Lifespan: Default,
+ *    - Liveliness: System default,
+ *    - Liveliness lease duration: default,
+ *    - Avoid ros namespace conventions: false
+ */
 class RCLCPP_PUBLIC ParametersQoS : public QoS
 {
 public:
@@ -171,6 +206,18 @@ public:
   ));
 };
 
+/**
+ * Services QoS class
+ *    - History: Keep last,
+ *    - Depth: 10,
+ *    - Reliability: Reliable,
+ *    - Durability: Volatile,
+ *    - Deadline: Default,
+ *    - Lifespan: Default,
+ *    - Liveliness: System default,
+ *    - Liveliness lease duration: default,
+ *    - Avoid ros namespace conventions: false
+ */
 class RCLCPP_PUBLIC ServicesQoS : public QoS
 {
 public:
@@ -181,6 +228,18 @@ public:
   ));
 };
 
+/**
+ * Parameter events QoS class
+ *    - History: Keep last,
+ *    - Depth: 1000,
+ *    - Reliability: Reliable,
+ *    - Durability: Volatile,
+ *    - Deadline: Default,
+ *    - Lifespan: Default,
+ *    - Liveliness: System default,
+ *    - Liveliness lease duration: default,
+ *    - Avoid ros namespace conventions: false
+ */
 class RCLCPP_PUBLIC ParameterEventsQoS : public QoS
 {
 public:
@@ -191,6 +250,18 @@ public:
   ));
 };
 
+/**
+ * System defaults QoS class
+ *    - History: System default,
+ *    - Depth: System default,
+ *    - Reliability: System default,
+ *    - Durability: System default,
+ *    - Deadline: Default,
+ *    - Lifespan: Default,
+ *    - Liveliness: System default,
+ *    - Liveliness lease duration: System default,
+ *    - Avoid ros namespace conventions: false
+ */
 class RCLCPP_PUBLIC SystemDefaultsQoS : public QoS
 {
 public:

rclcpp/include/rclcpp/qos_event.hpp

@@ -16,8 +16,10 @@
 #define RCLCPP__QOS_EVENT_HPP_
 
 #include <functional>
+#include <string>
 
 #include "rcl/error_handling.h"
+#include "rmw/incompatible_qos_events_statuses.h"
 
 #include "rcutils/logging_macros.h"
 
@@ -32,17 +34,23 @@ using QOSDeadlineRequestedInfo = rmw_requested_deadline_missed_status_t;
 using QOSDeadlineOfferedInfo = rmw_offered_deadline_missed_status_t;
 using QOSLivelinessChangedInfo = rmw_liveliness_changed_status_t;
 using QOSLivelinessLostInfo = rmw_liveliness_lost_status_t;
+using QOSOfferedIncompatibleQoSInfo = rmw_offered_qos_incompatible_event_status_t;
+using QOSRequestedIncompatibleQoSInfo = rmw_requested_qos_incompatible_event_status_t;
 
 using QOSDeadlineRequestedCallbackType = std::function<void (QOSDeadlineRequestedInfo &)>;
 using QOSDeadlineOfferedCallbackType = std::function<void (QOSDeadlineOfferedInfo &)>;
 using QOSLivelinessChangedCallbackType = std::function<void (QOSLivelinessChangedInfo &)>;
 using QOSLivelinessLostCallbackType = std::function<void (QOSLivelinessLostInfo &)>;
+using QOSOfferedIncompatibleQoSCallbackType = std::function<void (QOSOfferedIncompatibleQoSInfo &)>;
+using QOSRequestedIncompatibleQoSCallbackType =
+  std::function<void (QOSRequestedIncompatibleQoSInfo &)>;
 
 /// Contains callbacks for various types of events a Publisher can receive from the middleware.
 struct PublisherEventCallbacks
 {
   QOSDeadlineOfferedCallbackType deadline_callback;
   QOSLivelinessLostCallbackType liveliness_callback;
+  QOSOfferedIncompatibleQoSCallbackType incompatible_qos_callback;
 };
 
 /// Contains callbacks for non-message events that a Subscription can receive from the middleware.
@@ -50,6 +58,22 @@ struct SubscriptionEventCallbacks
 {
   QOSDeadlineRequestedCallbackType deadline_callback;
   QOSLivelinessChangedCallbackType liveliness_callback;
+  QOSRequestedIncompatibleQoSCallbackType incompatible_qos_callback;
+};
+
+class UnsupportedEventTypeException : public exceptions::RCLErrorBase, public std::runtime_error
+{
+public:
+  RCLCPP_PUBLIC
+  UnsupportedEventTypeException(
+    rcl_ret_t ret,
+    const rcl_error_state_t * error_state,
+    const std::string & prefix);
+
+  RCLCPP_PUBLIC
+  UnsupportedEventTypeException(
+    const exceptions::RCLErrorBase & base_exc,
+    const std::string & prefix);
 };
 
 class QOSEventHandlerBase : public Waitable
@@ -78,11 +102,11 @@ protected:
   size_t wait_set_event_index_;
 };
 
-template<typename EventCallbackT>
+template<typename EventCallbackT, typename ParentHandleT>
 class QOSEventHandler : public QOSEventHandlerBase
 {
 public:
-  template<typename InitFuncT, typename ParentHandleT, typename EventTypeEnum>
+  template<typename InitFuncT, typename EventTypeEnum>
   QOSEventHandler(
     const EventCallbackT & callback,
     InitFuncT init_func,
@@ -90,10 +114,17 @@ public:
     EventTypeEnum event_type)
   : event_callback_(callback)
   {
+    parent_handle_ = parent_handle;
     event_handle_ = rcl_get_zero_initialized_event();
-    rcl_ret_t ret = init_func(&event_handle_, parent_handle, event_type);
+    rcl_ret_t ret = init_func(&event_handle_, parent_handle.get(), event_type);
     if (ret != RCL_RET_OK) {
-      rclcpp::exceptions::throw_from_rcl_error(ret, "could not create event");
+      if (ret == RCL_RET_UNSUPPORTED) {
+        UnsupportedEventTypeException exc(ret, rcl_get_error_state(), "Failed to initialize event");
+        rcl_reset_error();
+        throw exc;
+      } else {
+        rclcpp::exceptions::throw_from_rcl_error(ret, "Failed to initialize event");
+      }
     }
   }
 
@@ -118,6 +149,7 @@ private:
   using EventCallbackInfoT = typename std::remove_reference<typename
       rclcpp::function_traits::function_traits<EventCallbackT>::template argument_type<0>>::type;
 
+  ParentHandleT parent_handle_;
   EventCallbackT event_callback_;
 };
 

rclcpp/include/rclcpp/rate.hpp

@@ -31,6 +31,7 @@ class RateBase
 public:
   RCLCPP_SMART_PTR_DEFINITIONS_NOT_COPYABLE(RateBase)
 
+  virtual ~RateBase() {}
   virtual bool sleep() = 0;
   virtual bool is_steady() const = 0;
   virtual void reset() = 0;

rclcpp/include/rclcpp/rclcpp.hpp

@@ -81,7 +81,7 @@
  *   - rclcpp/executors/multi_threaded_executor.hpp
  * - CallbackGroups (mechanism for enforcing concurrency rules for callbacks):
  *   - rclcpp::Node::create_callback_group()
- *   - rclcpp::callback_group::CallbackGroup
+ *   - rclcpp::CallbackGroup
  *   - rclcpp/callback_group.hpp
  *
  * Additionally, there are some methods for introspecting the ROS graph:
@@ -128,6 +128,7 @@
  *   - rclcpp/context.hpp
  *   - rclcpp/contexts/default_context.hpp
  * - Various utilities:
+ *   - rclcpp/duration.hpp
  *   - rclcpp/function_traits.hpp
  *   - rclcpp/macros.hpp
  *   - rclcpp/scope_exit.hpp
@@ -143,6 +144,7 @@
 #include <memory>
 
 #include "rclcpp/executors.hpp"
+#include "rclcpp/guard_condition.hpp"
 #include "rclcpp/logging.hpp"
 #include "rclcpp/node.hpp"
 #include "rclcpp/parameter.hpp"
@@ -152,6 +154,7 @@
 #include "rclcpp/time.hpp"
 #include "rclcpp/utilities.hpp"
 #include "rclcpp/visibility_control.hpp"
+#include "rclcpp/wait_set.hpp"
 #include "rclcpp/waitable.hpp"
 
 #endif  // RCLCPP__RCLCPP_HPP_

rclcpp/include/rclcpp/serialization.hpp

@@ -0,0 +1,98 @@
+// Copyright 2020 Open Source Robotics Foundation, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef RCLCPP__SERIALIZATION_HPP_
+#define RCLCPP__SERIALIZATION_HPP_
+
+#include <memory>
+#include <stdexcept>
+#include <string>
+
+#include "rclcpp/visibility_control.hpp"
+
+#include "rcl/types.h"
+
+#include "rosidl_runtime_c/message_type_support_struct.h"
+
+#include "rosidl_typesupport_cpp/message_type_support.hpp"
+
+namespace rclcpp
+{
+
+class SerializedMessage;
+
+namespace serialization_traits
+{
+// trait to check if type is the object oriented serialized message
+template<typename T>
+struct is_serialized_message_class : std::false_type
+{};
+
+template<>
+struct is_serialized_message_class<SerializedMessage>: std::true_type
+{};
+}  // namespace serialization_traits
+
+/// Interface to (de)serialize a message
+class RCLCPP_PUBLIC_TYPE SerializationBase
+{
+public:
+  /// Constructor of SerializationBase
+  /**
+   * \param[in] type_support handle for the message type support
+   * to be used for serialization and deserialization.
+   */
+  explicit SerializationBase(const rosidl_message_type_support_t * type_support);
+
+  /// Destructor of SerializationBase
+  virtual ~SerializationBase() = default;
+
+  /// Serialize a ROS2 message to a serialized stream
+  /**
+   * \param[in] ros_message The ROS2 message which is read and serialized by rmw.
+   * \param[out] serialized_message The serialized message.
+   */
+  void serialize_message(
+    const void * ros_message, SerializedMessage * serialized_message) const;
+
+  /// Deserialize a serialized stream to a ROS message
+  /**
+   * \param[in] serialized_message The serialized message to be converted to ROS2 by rmw.
+   * \param[out] ros_message The deserialized ROS2 message.
+   */
+  void deserialize_message(
+    const SerializedMessage * serialized_message, void * ros_message) const;
+
+private:
+  const rosidl_message_type_support_t * type_support_;
+};
+
+/// Default implementation to (de)serialize a message by using rmw_(de)serialize
+template<typename MessageT>
+class Serialization : public SerializationBase
+{
+public:
+  /// Constructor of Serialization
+  Serialization()
+  : SerializationBase(rosidl_typesupport_cpp::get_message_type_support_handle<MessageT>())
+  {
+    static_assert(
+      !serialization_traits::is_serialized_message_class<MessageT>::value,
+      "Serialization of serialized message to serialized message is not possible.");
+  }
+};
+
+}  // namespace rclcpp
+
+#endif  // RCLCPP__SERIALIZATION_HPP_

rclcpp/include/rclcpp/serialized_message.hpp

@@ -0,0 +1,121 @@
+// Copyright 2020 Open Source Robotics Foundation, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef RCLCPP__SERIALIZED_MESSAGE_HPP_
+#define RCLCPP__SERIALIZED_MESSAGE_HPP_
+
+#include "rcl/allocator.h"
+#include "rcl/types.h"
+
+#include "rclcpp/visibility_control.hpp"
+
+namespace rclcpp
+{
+
+/// Object oriented version of rcl_serialized_message_t with destructor to avoid memory leaks
+class RCLCPP_PUBLIC_TYPE SerializedMessage
+{
+public:
+  /// Default constructor for a SerializedMessage
+  /**
+   * Default constructs a serialized message and initalizes it
+   * with initial capacity of 0.
+   * The allocator defaults to `rcl_get_default_allocator()`.
+   *
+   * \param[in] allocator The allocator to be used for the initialization.
+   */
+  explicit SerializedMessage(
+    const rcl_allocator_t & allocator = rcl_get_default_allocator());
+
+  /// Default constructor for a SerializedMessage
+  /**
+   * Default constructs a serialized message and initalizes it
+   * with the provided capacity.
+   * The allocator defaults to `rcl_get_default_allocator()`.
+   *
+   * \param[in] initial_capacity The amount of memory to be allocated.
+   * \param[in] allocator The allocator to be used for the initialization.
+   */
+  SerializedMessage(
+    size_t initial_capacity,
+    const rcl_allocator_t & allocator = rcl_get_default_allocator());
+
+  /// Copy Constructor for a SerializedMessage
+  SerializedMessage(const SerializedMessage & other);
+
+  /// Constructor for a SerializedMessage from a rcl_serialized_message_t
+  explicit SerializedMessage(const rcl_serialized_message_t & other);
+
+  /// Move Constructor for a SerializedMessage
+  SerializedMessage(SerializedMessage && other);
+
+  /// Constructor for a SerializedMessage from a moved rcl_serialized_message_t
+  explicit SerializedMessage(rcl_serialized_message_t && other);
+
+  /// Copy assignment operator
+  SerializedMessage & operator=(const SerializedMessage & other);
+
+  /// Copy assignment operator from a rcl_serialized_message_t
+  SerializedMessage & operator=(const rcl_serialized_message_t & other);
+
+  /// Move assignment operator
+  SerializedMessage & operator=(SerializedMessage && other);
+
+  /// Move assignment operator from a rcl_serialized_message_t
+  SerializedMessage & operator=(rcl_serialized_message_t && other);
+
+  /// Destructor for a SerializedMessage
+  virtual ~SerializedMessage();
+
+  /// Get the underlying rcl_serialized_t handle
+  rcl_serialized_message_t & get_rcl_serialized_message();
+
+  // Get a const handle to the underlying rcl_serialized_message_t
+  const rcl_serialized_message_t & get_rcl_serialized_message() const;
+
+  /// Get the size of the serialized data buffer
+  /**
+   * Note, this is different from the actual amount of allocated memory.
+   * This can be obtained via a call to `capacity`.
+   */
+  size_t size() const;
+
+  /// Get the size of allocated memory for the data buffer
+  /**
+   * Note, this is different from the amount of content in the buffer.
+   * This can be obtained via a call to `size`.
+   */
+  size_t capacity() const;
+
+  /// Allocate memory in the data buffer
+  /**
+   * The data buffer of the underlying rcl_serialized_message_t will be resized.
+   * This might change the data layout and invalidates all pointers to the data.
+   */
+  void reserve(size_t capacity);
+
+  /// Release the underlying rcl_serialized_message_t
+  /**
+   * The memory (i.e. the data buffer) of the serialized message will no longer
+   * be managed by this instance and the memory won't be deallocated on destruction.
+   */
+  rcl_serialized_message_t release_rcl_serialized_message();
+
+private:
+  rcl_serialized_message_t serialized_message_;
+};
+
+}  // namespace rclcpp
+
+#endif  // RCLCPP__SERIALIZED_MESSAGE_HPP_

rclcpp/include/rclcpp/service.hpp

@@ -15,6 +15,7 @@
 #ifndef RCLCPP__SERVICE_HPP_
 #define RCLCPP__SERVICE_HPP_
 
+#include <atomic>
 #include <functional>
 #include <iostream>
 #include <memory>
@@ -44,30 +45,82 @@ public:
   RCLCPP_SMART_PTR_DEFINITIONS_NOT_COPYABLE(ServiceBase)
 
   RCLCPP_PUBLIC
-  explicit ServiceBase(
-    std::shared_ptr<rcl_node_t> node_handle);
+  explicit ServiceBase(std::shared_ptr<rcl_node_t> node_handle);
 
   RCLCPP_PUBLIC
   virtual ~ServiceBase();
 
+  /// Return the name of the service.
+  /** \return The name of the service. */
   RCLCPP_PUBLIC
   const char *
   get_service_name();
 
+  /// Return the rcl_service_t service handle in a std::shared_ptr.
+  /**
+   * This handle remains valid after the Service is destroyed.
+   * The actual rcl service is not finalized until it is out of scope everywhere.
+   */
   RCLCPP_PUBLIC
   std::shared_ptr<rcl_service_t>
   get_service_handle();
 
+  /// Return the rcl_service_t service handle in a std::shared_ptr.
+  /**
+   * This handle remains valid after the Service is destroyed.
+   * The actual rcl service is not finalized until it is out of scope everywhere.
+   */
   RCLCPP_PUBLIC
   std::shared_ptr<const rcl_service_t>
   get_service_handle() const;
 
-  virtual std::shared_ptr<void> create_request() = 0;
-  virtual std::shared_ptr<rmw_request_id_t> create_request_header() = 0;
-  virtual void handle_request(
+  /// Take the next request from the service as a type erased pointer.
+  /**
+   * This type erased version of \sa Service::take_request() is useful when
+   * using the service in a type agnostic way with methods like
+   * ServiceBase::create_request(), ServiceBase::create_request_header(), and
+   * ServiceBase::handle_request().
+   *
+   * \param[out] request_out The type erased pointer to a service request object
+   *   into which the middleware will copy the taken request.
+   * \param[out] request_id_out The output id for the request which can be used
+   *   to associate response with this request in the future.
+   * \returns true if the request was taken, otherwise false.
+   * \throws rclcpp::exceptions::RCLError based exceptions if the underlying
+   *   rcl calls fail.
+   */
+  RCLCPP_PUBLIC
+  bool
+  take_type_erased_request(void * request_out, rmw_request_id_t & request_id_out);
+
+  virtual
+  std::shared_ptr<void>
+  create_request() = 0;
+
+  virtual
+  std::shared_ptr<rmw_request_id_t>
+  create_request_header() = 0;
+
+  virtual
+  void
+  handle_request(
     std::shared_ptr<rmw_request_id_t> request_header,
     std::shared_ptr<void> request) = 0;
 
+  /// Exchange the "in use by wait set" state for this service.
+  /**
+   * This is used to ensure this service is not used by multiple
+   * wait sets at the same time.
+   *
+   * \param[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.
+   */
+  RCLCPP_PUBLIC
+  bool
+  exchange_in_use_by_wait_set_state(bool in_use_state);
+
 protected:
   RCLCPP_DISABLE_COPY(ServiceBase)
 
@@ -83,6 +136,8 @@ protected:
 
   std::shared_ptr<rcl_service_t> service_handle_;
   bool owns_rcl_handle_ = true;
+
+  std::atomic<bool> in_use_by_wait_set_{false};
 };
 
 template<typename ServiceT>
@@ -101,6 +156,17 @@ public:
       std::shared_ptr<typename ServiceT::Response>)>;
   RCLCPP_SMART_PTR_DEFINITIONS(Service)
 
+  /// Default constructor.
+  /**
+   * The constructor for a Service is almost never called directly.
+   * Instead, services should be instantiated through the function
+   * rclcpp::create_service().
+   *
+   * \param[in] node_handle NodeBaseInterface pointer that is used in part of the setup.
+   * \param[in] service_name Name of the topic to publish to.
+   * \param[in] any_callback User defined callback to call when a client request is received.
+   * \param[in] service_options options for the subscription.
+   */
   Service(
     std::shared_ptr<rcl_node_t> node_handle,
     const std::string & service_name,
@@ -111,25 +177,16 @@ public:
     using rosidl_typesupport_cpp::get_service_type_support_handle;
     auto service_type_support_handle = get_service_type_support_handle<ServiceT>();
 
-    std::weak_ptr<rcl_node_t> weak_node_handle(node_handle_);
     // rcl does the static memory allocation here
     service_handle_ = std::shared_ptr<rcl_service_t>(
-      new rcl_service_t, [weak_node_handle](rcl_service_t * service)
+      new rcl_service_t, [handle = node_handle_](rcl_service_t * service)
       {
-        auto handle = weak_node_handle.lock();
-        if (handle) {
-          if (rcl_service_fini(service, handle.get()) != RCL_RET_OK) {
-            RCLCPP_ERROR(
-              rclcpp::get_node_logger(handle.get()).get_child("rclcpp"),
-              "Error in destruction of rcl service handle: %s",
-              rcl_get_error_string().str);
-            rcl_reset_error();
-          }
-        } else {
+        if (rcl_service_fini(service, handle.get()) != RCL_RET_OK) {
           RCLCPP_ERROR(
-            rclcpp::get_logger("rclcpp"),
-            "Error in destruction of rcl service handle: "
-            "the Node Handle was destructed too early. You will leak memory");
+            rclcpp::get_node_logger(handle.get()).get_child("rclcpp"),
+            "Error in destruction of rcl service handle: %s",
+            rcl_get_error_string().str);
+          rcl_reset_error();
         }
         delete service;
       });
@@ -159,8 +216,21 @@ public:
       rclcpp_service_callback_added,
       (const void *)get_service_handle().get(),
       (const void *)&any_callback_);
+#ifndef TRACETOOLS_DISABLED
+    any_callback_.register_callback_for_tracing();
+#endif
   }
 
+  /// Default constructor.
+  /**
+   * The constructor for a Service is almost never called directly.
+   * Instead, services should be instantiated through the function
+   * rclcpp::create_service().
+   *
+   * \param[in] node_handle NodeBaseInterface pointer that is used in part of the setup.
+   * \param[in] service_handle service handle.
+   * \param[in] any_callback User defined callback to call when a client request is received.
+   */
   Service(
     std::shared_ptr<rcl_node_t> node_handle,
     std::shared_ptr<rcl_service_t> service_handle,
@@ -181,8 +251,21 @@ public:
       rclcpp_service_callback_added,
       (const void *)get_service_handle().get(),
       (const void *)&any_callback_);
+#ifndef TRACETOOLS_DISABLED
+    any_callback_.register_callback_for_tracing();
+#endif
   }
 
+  /// Default constructor.
+  /**
+   * The constructor for a Service is almost never called directly.
+   * Instead, services should be instantiated through the function
+   * rclcpp::create_service().
+   *
+   * \param[in] node_handle NodeBaseInterface pointer that is used in part of the setup.
+   * \param[in] service_handle service handle.
+   * \param[in] any_callback User defined callback to call when a client request is received.
+   */
   Service(
     std::shared_ptr<rcl_node_t> node_handle,
     rcl_service_t * service_handle,
@@ -205,6 +288,9 @@ public:
       rclcpp_service_callback_added,
       (const void *)get_service_handle().get(),
       (const void *)&any_callback_);
+#ifndef TRACETOOLS_DISABLED
+    any_callback_.register_callback_for_tracing();
+#endif
   }
 
   Service() = delete;
@@ -213,36 +299,63 @@ public:
   {
   }
 
-  std::shared_ptr<void> create_request()
+  /// Take the next request from the service.
+  /**
+   * \sa ServiceBase::take_type_erased_request().
+   *
+   * \param[out] request_out The reference to a service request object
+   *   into which the middleware will copy the taken request.
+   * \param[out] request_id_out The output id for the request which can be used
+   *   to associate response with this request in the future.
+   * \returns true if the request was taken, otherwise false.
+   * \throws rclcpp::exceptions::RCLError based exceptions if the underlying
+   *   rcl calls fail.
+   */
+  bool
+  take_request(typename ServiceT::Request & request_out, rmw_request_id_t & request_id_out)
   {
-    return std::shared_ptr<void>(new typename ServiceT::Request());
+    return this->take_type_erased_request(&request_out, request_id_out);
   }
 
-  std::shared_ptr<rmw_request_id_t> create_request_header()
+  std::shared_ptr<void>
+  create_request() override
   {
-    // TODO(wjwwood): This should probably use rmw_request_id's allocator.
-    //                (since it is a C type)
-    return std::shared_ptr<rmw_request_id_t>(new rmw_request_id_t);
+    return std::make_shared<typename ServiceT::Request>();
   }
 
-  void handle_request(
+  std::shared_ptr<rmw_request_id_t>
+  create_request_header() override
+  {
+    return std::make_shared<rmw_request_id_t>();
+  }
+
+  void
+  handle_request(
     std::shared_ptr<rmw_request_id_t> request_header,
-    std::shared_ptr<void> request)
+    std::shared_ptr<void> request) override
   {
     auto typed_request = std::static_pointer_cast<typename ServiceT::Request>(request);
-    auto response = std::shared_ptr<typename ServiceT::Response>(new typename ServiceT::Response);
+    auto response = std::make_shared<typename ServiceT::Response>();
     any_callback_.dispatch(request_header, typed_request, response);
-    send_response(request_header, response);
+    send_response(*request_header, *response);
   }
 
-  void send_response(
+  [[deprecated("use the send_response() which takes references instead of shared pointers")]]
+  void
+  send_response(
     std::shared_ptr<rmw_request_id_t> req_id,
     std::shared_ptr<typename ServiceT::Response> response)
   {
-    rcl_ret_t status = rcl_send_response(get_service_handle().get(), req_id.get(), response.get());
+    send_response(*req_id, *response);
+  }
 
-    if (status != RCL_RET_OK) {
-      rclcpp::exceptions::throw_from_rcl_error(status, "failed to send response");
+  void
+  send_response(rmw_request_id_t & req_id, typename ServiceT::Response & response)
+  {
+    rcl_ret_t ret = rcl_send_response(get_service_handle().get(), &req_id, &response);
+
+    if (ret != RCL_RET_OK) {
+      rclcpp::exceptions::throw_from_rcl_error(ret, "failed to send response");
     }
   }
 

rclcpp/include/rclcpp/strategies/allocator_memory_strategy.hpp

@@ -61,7 +61,7 @@ public:
     allocator_ = std::make_shared<VoidAlloc>();
   }
 
-  void add_guard_condition(const rcl_guard_condition_t * guard_condition)
+  void add_guard_condition(const rcl_guard_condition_t * guard_condition) override
   {
     for (const auto & existing_guard_condition : guard_conditions_) {
       if (existing_guard_condition == guard_condition) {
@@ -71,7 +71,7 @@ public:
     guard_conditions_.push_back(guard_condition);
   }
 
-  void remove_guard_condition(const rcl_guard_condition_t * guard_condition)
+  void remove_guard_condition(const rcl_guard_condition_t * guard_condition) override
   {
     for (auto it = guard_conditions_.begin(); it != guard_conditions_.end(); ++it) {
       if (*it == guard_condition) {
@@ -81,7 +81,7 @@ public:
     }
   }
 
-  void clear_handles()
+  void clear_handles() override
   {
     subscription_handles_.clear();
     service_handles_.clear();
@@ -90,7 +90,7 @@ public:
     waitable_handles_.clear();
   }
 
-  virtual void remove_null_handles(rcl_wait_set_t * wait_set)
+  void remove_null_handles(rcl_wait_set_t * wait_set) override
   {
     // TODO(jacobperron): Check if wait set sizes are what we expect them to be?
     //                    e.g. wait_set->size_of_clients == client_handles_.size()
@@ -150,7 +150,7 @@ public:
     );
   }
 
-  bool collect_entities(const WeakNodeList & weak_nodes)
+  bool collect_entities(const WeakNodeList & weak_nodes) override
   {
     bool has_invalid_weak_nodes = false;
     for (auto & weak_node : weak_nodes) {
@@ -169,20 +169,23 @@ public:
             subscription_handles_.push_back(subscription->get_subscription_handle());
             return false;
           });
-
-        group->find_service_ptrs_if([this](const rclcpp::ServiceBase::SharedPtr & service) {
+        group->find_service_ptrs_if(
+          [this](const rclcpp::ServiceBase::SharedPtr & service) {
             service_handles_.push_back(service->get_service_handle());
             return false;
           });
-        group->find_client_ptrs_if([this](const rclcpp::ClientBase::SharedPtr & client) {
+        group->find_client_ptrs_if(
+          [this](const rclcpp::ClientBase::SharedPtr & client) {
             client_handles_.push_back(client->get_client_handle());
             return false;
           });
-        group->find_timer_ptrs_if([this](const rclcpp::TimerBase::SharedPtr & timer) {
+        group->find_timer_ptrs_if(
+          [this](const rclcpp::TimerBase::SharedPtr & timer) {
             timer_handles_.push_back(timer->get_timer_handle());
             return false;
           });
-        group->find_waitable_ptrs_if([this](const rclcpp::Waitable::SharedPtr & waitable) {
+        group->find_waitable_ptrs_if(
+          [this](const rclcpp::Waitable::SharedPtr & waitable) {
             waitable_handles_.push_back(waitable);
             return false;
           });
@@ -191,7 +194,15 @@ public:
     return has_invalid_weak_nodes;
   }
 
-  bool add_handles_to_wait_set(rcl_wait_set_t * wait_set)
+  void add_waitable_handle(const rclcpp::Waitable::SharedPtr & waitable) override
+  {
+    if (nullptr == waitable) {
+      throw std::runtime_error("waitable object unexpectedly nullptr");
+    }
+    waitable_handles_.push_back(waitable);
+  }
+
+  bool add_handles_to_wait_set(rcl_wait_set_t * wait_set) override
   {
     for (auto subscription : subscription_handles_) {
       if (rcl_wait_set_add_subscription(wait_set, subscription.get(), NULL) != RCL_RET_OK) {
@@ -250,10 +261,10 @@ public:
     return true;
   }
 
-  virtual void
+  void
   get_next_subscription(
-    executor::AnyExecutable & any_exec,
-    const WeakNodeList & weak_nodes)
+    rclcpp::AnyExecutable & any_exec,
+    const WeakNodeList & weak_nodes) override
   {
     auto it = subscription_handles_.begin();
     while (it != subscription_handles_.end()) {
@@ -285,10 +296,10 @@ public:
     }
   }
 
-  virtual void
+  void
   get_next_service(
-    executor::AnyExecutable & any_exec,
-    const WeakNodeList & weak_nodes)
+    rclcpp::AnyExecutable & any_exec,
+    const WeakNodeList & weak_nodes) override
   {
     auto it = service_handles_.begin();
     while (it != service_handles_.end()) {
@@ -320,8 +331,8 @@ public:
     }
   }
 
-  virtual void
-  get_next_client(executor::AnyExecutable & any_exec, const WeakNodeList & weak_nodes)
+  void
+  get_next_client(rclcpp::AnyExecutable & any_exec, const WeakNodeList & weak_nodes) override
   {
     auto it = client_handles_.begin();
     while (it != client_handles_.end()) {
@@ -353,10 +364,10 @@ public:
     }
   }
 
-  virtual void
+  void
   get_next_timer(
-    executor::AnyExecutable & any_exec,
-    const WeakNodeList & weak_nodes)
+    rclcpp::AnyExecutable & any_exec,
+    const WeakNodeList & weak_nodes) override
   {
     auto it = timer_handles_.begin();
     while (it != timer_handles_.end()) {
@@ -388,8 +399,8 @@ public:
     }
   }
 
-  virtual void
-  get_next_waitable(executor::AnyExecutable & any_exec, const WeakNodeList & weak_nodes)
+  void
+  get_next_waitable(rclcpp::AnyExecutable & any_exec, const WeakNodeList & weak_nodes) override
   {
     auto it = waitable_handles_.begin();
     while (it != waitable_handles_.end()) {
@@ -421,12 +432,12 @@ public:
     }
   }
 
-  virtual rcl_allocator_t get_allocator()
+  rcl_allocator_t get_allocator() override
   {
     return rclcpp::allocator::get_rcl_allocator<void *, VoidAlloc>(*allocator_.get());
   }
 
-  size_t number_of_ready_subscriptions() const
+  size_t number_of_ready_subscriptions() const override
   {
     size_t number_of_subscriptions = subscription_handles_.size();
     for (auto waitable : waitable_handles_) {
@@ -435,7 +446,7 @@ public:
     return number_of_subscriptions;
   }
 
-  size_t number_of_ready_services() const
+  size_t number_of_ready_services() const override
   {
     size_t number_of_services = service_handles_.size();
     for (auto waitable : waitable_handles_) {
@@ -444,7 +455,7 @@ public:
     return number_of_services;
   }
 
-  size_t number_of_ready_events() const
+  size_t number_of_ready_events() const override
   {
     size_t number_of_events = 0;
     for (auto waitable : waitable_handles_) {
@@ -453,7 +464,7 @@ public:
     return number_of_events;
   }
 
-  size_t number_of_ready_clients() const
+  size_t number_of_ready_clients() const override
   {
     size_t number_of_clients = client_handles_.size();
     for (auto waitable : waitable_handles_) {
@@ -462,7 +473,7 @@ public:
     return number_of_clients;
   }
 
-  size_t number_of_guard_conditions() const
+  size_t number_of_guard_conditions() const override
   {
     size_t number_of_guard_conditions = guard_conditions_.size();
     for (auto waitable : waitable_handles_) {
@@ -471,7 +482,7 @@ public:
     return number_of_guard_conditions;
   }
 
-  size_t number_of_ready_timers() const
+  size_t number_of_ready_timers() const override
   {
     size_t number_of_timers = timer_handles_.size();
     for (auto waitable : waitable_handles_) {
@@ -480,7 +491,7 @@ public:
     return number_of_timers;
   }
 
-  size_t number_of_waitables() const
+  size_t number_of_waitables() const override
   {
     return waitable_handles_.size();
   }

rclcpp/include/rclcpp/strategies/message_pool_memory_strategy.hpp

@@ -17,6 +17,8 @@
 
 #include <memory>
 
+#include "rosidl_runtime_cpp/traits.hpp"
+
 #include "rclcpp/macros.hpp"
 #include "rclcpp/message_memory_strategy.hpp"
 #include "rclcpp/visibility_control.hpp"

rclcpp/include/rclcpp/subscription.hpp

@@ -18,6 +18,7 @@
 #include <rmw/error_handling.h>
 #include <rmw/rmw.h>
 
+#include <chrono>
 #include <functional>
 #include <iostream>
 #include <memory>
@@ -25,7 +26,6 @@
 #include <string>
 #include <utility>
 
-
 #include "rcl/error_handling.h"
 #include "rcl/subscription.h"
 
@@ -38,6 +38,7 @@
 #include "rclcpp/experimental/subscription_intra_process.hpp"
 #include "rclcpp/logging.hpp"
 #include "rclcpp/macros.hpp"
+#include "rclcpp/message_info.hpp"
 #include "rclcpp/message_memory_strategy.hpp"
 #include "rclcpp/node_interfaces/node_base_interface.hpp"
 #include "rclcpp/subscription_base.hpp"
@@ -46,6 +47,7 @@
 #include "rclcpp/type_support_decl.hpp"
 #include "rclcpp/visibility_control.hpp"
 #include "rclcpp/waitable.hpp"
+#include "rclcpp/topic_statistics/subscription_topic_statistics.hpp"
 #include "tracetools/tracetools.h"
 
 namespace rclcpp
@@ -74,6 +76,8 @@ public:
   using MessageDeleter = allocator::Deleter<MessageAllocator, CallbackMessageT>;
   using ConstMessageSharedPtr = std::shared_ptr<const CallbackMessageT>;
   using MessageUniquePtr = std::unique_ptr<CallbackMessageT, MessageDeleter>;
+  using SubscriptionTopicStatisticsSharedPtr =
+    std::shared_ptr<rclcpp::topic_statistics::SubscriptionTopicStatistics<CallbackMessageT>>;
 
   RCLCPP_SMART_PTR_DEFINITIONS(Subscription)
 
@@ -86,9 +90,14 @@ public:
    * \param[in] node_base NodeBaseInterface pointer that is used in part of the setup.
    * \param[in] type_support_handle rosidl type support struct, for the Message type of the topic.
    * \param[in] topic_name Name of the topic to subscribe to.
+   * \param[in] qos QoS profile for Subcription.
    * \param[in] callback User defined callback to call when a message is received.
    * \param[in] options options for the subscription.
    * \param[in] message_memory_strategy The memory strategy to be used for managing message memory.
+   * \param[in] subscription_topic_statistics Optional pointer to a topic statistics subcription.
+   * \throws std::invalid_argument if the QoS is uncompatible with intra-process (if one
+   *   of the following conditions are true: qos_profile.history == RMW_QOS_POLICY_HISTORY_KEEP_ALL,
+   *   qos_profile.depth == 0 or qos_profile.durability != RMW_QOS_POLICY_DURABILITY_VOLATILE).
    */
   Subscription(
     rclcpp::node_interfaces::NodeBaseInterface * node_base,
@@ -97,7 +106,8 @@ public:
     const rclcpp::QoS & qos,
     AnySubscriptionCallback<CallbackMessageT, AllocatorT> callback,
     const rclcpp::SubscriptionOptionsWithAllocator<AllocatorT> & options,
-    typename MessageMemoryStrategyT::SharedPtr message_memory_strategy)
+    typename MessageMemoryStrategyT::SharedPtr message_memory_strategy,
+    SubscriptionTopicStatisticsSharedPtr subscription_topic_statistics = nullptr)
   : SubscriptionBase(
       node_base,
       type_support_handle,
@@ -118,40 +128,55 @@ public:
         options.event_callbacks.liveliness_callback,
         RCL_SUBSCRIPTION_LIVELINESS_CHANGED);
     }
+    if (options.event_callbacks.incompatible_qos_callback) {
+      this->add_event_handler(
+        options.event_callbacks.incompatible_qos_callback,
+        RCL_SUBSCRIPTION_REQUESTED_INCOMPATIBLE_QOS);
+    } else if (options_.use_default_callbacks) {
+      // Register default callback when not specified
+      try {
+        this->add_event_handler(
+          [this](QOSRequestedIncompatibleQoSInfo & info) {
+            this->default_incompatible_qos_callback(info);
+          },
+          RCL_SUBSCRIPTION_REQUESTED_INCOMPATIBLE_QOS);
+      } catch (UnsupportedEventTypeException & /*exc*/) {
+        // pass
+      }
+    }
 
     // Setup intra process publishing if requested.
     if (rclcpp::detail::resolve_use_intra_process(options, *node_base)) {
       using rclcpp::detail::resolve_intra_process_buffer_type;
 
       // Check if the QoS is compatible with intra-process.
-      if (qos.get_rmw_qos_profile().history == RMW_QOS_POLICY_HISTORY_KEEP_ALL) {
+      rmw_qos_profile_t qos_profile = get_actual_qos().get_rmw_qos_profile();
+      if (qos_profile.history == RMW_QOS_POLICY_HISTORY_KEEP_ALL) {
         throw std::invalid_argument(
                 "intraprocess communication is not allowed with keep all history qos policy");
       }
-      if (qos.get_rmw_qos_profile().depth == 0) {
+      if (qos_profile.depth == 0) {
         throw std::invalid_argument(
                 "intraprocess communication is not allowed with 0 depth qos policy");
       }
-      if (qos.get_rmw_qos_profile().durability != RMW_QOS_POLICY_DURABILITY_VOLATILE) {
+      if (qos_profile.durability != RMW_QOS_POLICY_DURABILITY_VOLATILE) {
         throw std::invalid_argument(
                 "intraprocess communication allowed only with volatile durability");
       }
 
       // First create a SubscriptionIntraProcess which will be given to the intra-process manager.
       auto context = node_base->get_context();
-      auto subscription_intra_process = std::make_shared<
-        rclcpp::experimental::SubscriptionIntraProcess<
-          CallbackMessageT,
-          AllocatorT,
-          typename MessageUniquePtr::deleter_type
-        >>(
+      using SubscriptionIntraProcessT = rclcpp::experimental::SubscriptionIntraProcess<
+        CallbackMessageT,
+        AllocatorT,
+        typename MessageUniquePtr::deleter_type>;
+      auto subscription_intra_process = std::make_shared<SubscriptionIntraProcessT>(
         callback,
         options.get_allocator(),
         context,
-        this->get_topic_name(),    // important to get like this, as it has the fully-qualified name
-        qos.get_rmw_qos_profile(),
-        resolve_intra_process_buffer_type(options.intra_process_buffer_type, callback)
-        );
+        this->get_topic_name(),  // important to get like this, as it has the fully-qualified name
+        qos_profile,
+        resolve_intra_process_buffer_type(options.intra_process_buffer_type, callback));
       TRACEPOINT(
         rclcpp_subscription_init,
         (const void *)get_subscription_handle().get(),
@@ -164,6 +189,10 @@ public:
       this->setup_intra_process(intra_process_subscription_id, ipm);
     }
 
+    if (subscription_topic_statistics != nullptr) {
+      this->subscription_topic_statistics_ = std::move(subscription_topic_statistics);
+    }
+
     TRACEPOINT(
       rclcpp_subscription_init,
       (const void *)get_subscription_handle().get(),
@@ -175,11 +204,14 @@ public:
     // The callback object gets copied, so if registration is done too early/before this point
     // (e.g. in `AnySubscriptionCallback::set()`), its address won't match any address used later
     // in subsequent tracepoints.
+#ifndef TRACETOOLS_DISABLED
     any_callback_.register_callback_for_tracing();
+#endif
   }
 
   /// Called after construction to continue setup that requires shared_from_this().
-  void post_init_setup(
+  void
+  post_init_setup(
     rclcpp::node_interfaces::NodeBaseInterface * node_base,
     const rclcpp::QoS & qos,
     const rclcpp::SubscriptionOptionsWithAllocator<AllocatorT> & options)
@@ -189,19 +221,32 @@ public:
     (void)options;
   }
 
-  /// Support dynamically setting the message memory strategy.
+  /// Take the next message from the inter-process subscription.
   /**
-   * Behavior may be undefined if called while the subscription could be executing.
-   * \param[in] message_memory_strategy Shared pointer to the memory strategy to set.
+   * Data may be taken (written) into the message_out and message_info_out even
+   * if false is returned.
+   * Specifically in the case of dropping redundant intra-process data, where
+   * data is received via both intra-process and inter-process (due to the
+   * underlying middleware being unabled to avoid this duplicate delivery) and
+   * so inter-process data from those intra-process publishers is ignored, but
+   * it has to be taken to know if it came from an intra-process publisher or
+   * not, and therefore could be dropped.
+   *
+   * \sa SubscriptionBase::take_type_erased()
+   *
+   * \param[out] message_out The message into which take will copy the data.
+   * \param[out] message_info_out The message info for the taken message.
+   * \returns true if data was taken and is valid, otherwise false
+   * \throws any rcl errors from rcl_take, \sa rclcpp::exceptions::throw_from_rcl_error()
    */
-  void set_message_memory_strategy(
-    typename message_memory_strategy::MessageMemoryStrategy<CallbackMessageT,
-    AllocatorT>::SharedPtr message_memory_strategy)
+  bool
+  take(CallbackMessageT & message_out, rclcpp::MessageInfo & message_info_out)
   {
-    message_memory_strategy_ = message_memory_strategy;
+    return this->take_type_erased(static_cast<void *>(&message_out), message_info_out);
   }
 
-  std::shared_ptr<void> create_message() override
+  std::shared_ptr<void>
+  create_message() override
   {
     /* The default message memory strategy provides a dynamically allocated message on each call to
      * create_message, though alternative memory strategies that re-use a preallocated message may be
@@ -210,48 +255,88 @@ public:
     return message_memory_strategy_->borrow_message();
   }
 
-  std::shared_ptr<rcl_serialized_message_t> create_serialized_message() override
+  std::shared_ptr<rclcpp::SerializedMessage>
+  create_serialized_message() override
   {
     return message_memory_strategy_->borrow_serialized_message();
   }
 
-  void handle_message(
-    std::shared_ptr<void> & message, const rmw_message_info_t & message_info) override
+  void
+  handle_message(
+    std::shared_ptr<void> & message,
+    const rclcpp::MessageInfo & message_info) override
   {
-    if (matches_any_intra_process_publishers(&message_info.publisher_gid)) {
+    if (matches_any_intra_process_publishers(&message_info.get_rmw_message_info().publisher_gid)) {
       // In this case, the message will be delivered via intra process and
       // we should ignore this copy of the message.
       return;
     }
     auto typed_message = std::static_pointer_cast<CallbackMessageT>(message);
     any_callback_.dispatch(typed_message, message_info);
+
+    if (subscription_topic_statistics_) {
+      const auto nanos = std::chrono::time_point_cast<std::chrono::nanoseconds>(
+        std::chrono::system_clock::now());
+      const auto time = rclcpp::Time(nanos.time_since_epoch().count());
+      subscription_topic_statistics_->handle_message(*typed_message, time);
+    }
   }
 
   void
   handle_loaned_message(
-    void * loaned_message, const rmw_message_info_t & message_info) override
+    void * loaned_message,
+    const rclcpp::MessageInfo & message_info) override
   {
+    if (matches_any_intra_process_publishers(&message_info.get_rmw_message_info().publisher_gid)) {
+      // In this case, the message will be delivered via intra process and
+      // we should ignore this copy of the message.
+      return;
+    }
+
     auto typed_message = static_cast<CallbackMessageT *>(loaned_message);
     // message is loaned, so we have to make sure that the deleter does not deallocate the message
     auto sptr = std::shared_ptr<CallbackMessageT>(
       typed_message, [](CallbackMessageT * msg) {(void) msg;});
+
+    std::chrono::time_point<std::chrono::system_clock> now;
+    if (subscription_topic_statistics_) {
+      // get current time before executing callback to
+      // exclude callback duration from topic statistics result.
+      now = std::chrono::system_clock::now();
+    }
+
     any_callback_.dispatch(sptr, message_info);
+
+    if (subscription_topic_statistics_) {
+      const auto nanos = std::chrono::time_point_cast<std::chrono::nanoseconds>(now);
+      const auto time = rclcpp::Time(nanos.time_since_epoch().count());
+      subscription_topic_statistics_->handle_message(*typed_message, time);
+    }
   }
 
   /// Return the borrowed message.
-  /** \param message message to be returned */
-  void return_message(std::shared_ptr<void> & message) override
+  /**
+   * \param[inout] message message to be returned
+   */
+  void
+  return_message(std::shared_ptr<void> & message) override
   {
     auto typed_message = std::static_pointer_cast<CallbackMessageT>(message);
     message_memory_strategy_->return_message(typed_message);
   }
 
-  void return_serialized_message(std::shared_ptr<rcl_serialized_message_t> & message) override
+  /// Return the borrowed serialized message.
+  /**
+   * \param[inout] message serialized message to be returned
+   */
+  void
+  return_serialized_message(std::shared_ptr<rclcpp::SerializedMessage> & message) override
   {
     message_memory_strategy_->return_serialized_message(message);
   }
 
-  bool use_take_shared_method() const
+  bool
+  use_take_shared_method() const
   {
     return any_callback_.use_take_shared_method();
   }
@@ -268,6 +353,8 @@ private:
   const rclcpp::SubscriptionOptionsWithAllocator<AllocatorT> options_;
   typename message_memory_strategy::MessageMemoryStrategy<CallbackMessageT, AllocatorT>::SharedPtr
     message_memory_strategy_;
+  /// Component which computes and publishes topic statistics for this subscriber
+  SubscriptionTopicStatisticsSharedPtr subscription_topic_statistics_{nullptr};
 };
 
 }  // namespace rclcpp

rclcpp/include/rclcpp/subscription_base.hpp

@@ -15,9 +15,12 @@
 #ifndef RCLCPP__SUBSCRIPTION_BASE_HPP_
 #define RCLCPP__SUBSCRIPTION_BASE_HPP_
 
+#include <atomic>
 #include <memory>
 #include <string>
+#include <unordered_map>
 #include <vector>
+#include <utility>
 
 #include "rcl/subscription.h"
 
@@ -27,8 +30,10 @@
 #include "rclcpp/experimental/intra_process_manager.hpp"
 #include "rclcpp/experimental/subscription_intra_process_base.hpp"
 #include "rclcpp/macros.hpp"
+#include "rclcpp/message_info.hpp"
 #include "rclcpp/qos.hpp"
 #include "rclcpp/qos_event.hpp"
+#include "rclcpp/serialized_message.hpp"
 #include "rclcpp/type_support_decl.hpp"
 #include "rclcpp/visibility_control.hpp"
 
@@ -86,7 +91,7 @@ public:
   get_subscription_handle();
 
   RCLCPP_PUBLIC
-  const std::shared_ptr<rcl_subscription_t>
+  std::shared_ptr<const rcl_subscription_t>
   get_subscription_handle() const;
 
   /// Get all the QoS event handlers associated with this subscription.
@@ -105,11 +110,51 @@ public:
    * May throw runtime_error when an unexpected error occurs.
    *
    * \return The actual qos settings.
+   * \throws std::runtime_error if failed to get qos settings
    */
   RCLCPP_PUBLIC
   rclcpp::QoS
   get_actual_qos() const;
 
+  /// Take the next inter-process message from the subscription as a type erased pointer.
+  /**
+   * \sa Subscription::take() for details on how this function works.
+   *
+   * The only difference is that it takes a type erased pointer rather than a
+   * reference to the exact message type.
+   *
+   * This type erased version facilitates using the subscriptions in a type
+   * agnostic way using SubscriptionBase::create_message() and
+   * SubscriptionBase::handle_message().
+   *
+   * \param[out] message_out The type erased message pointer into which take
+   *   will copy the data.
+   * \param[out] message_info_out The message info for the taken message.
+   * \returns true if data was taken and is valid, otherwise false
+   * \throws any rcl errors from rcl_take, \sa rclcpp::exceptions::throw_from_rcl_error()
+   */
+  RCLCPP_PUBLIC
+  bool
+  take_type_erased(void * message_out, rclcpp::MessageInfo & message_info_out);
+
+  /// Take the next inter-process message, in its serialized form, from the subscription.
+  /**
+   * For now, if data is taken (written) into the message_out and
+   * message_info_out then true will be returned.
+   * Unlike Subscription::take(), taking data serialized is not possible via
+   * intra-process for the time being, so it will not need to de-duplicate
+   * data in any case.
+   *
+   * \param[out] message_out The serialized message data structure used to
+   *   store the taken message.
+   * \param[out] message_info_out The message info for the taken message.
+   * \returns true if data was taken and is valid, otherwise false
+   * \throws any rcl errors from rcl_take, \sa rclcpp::exceptions::throw_from_rcl_error()
+   */
+  RCLCPP_PUBLIC
+  bool
+  take_serialized(rclcpp::SerializedMessage & message_out, rclcpp::MessageInfo & message_info_out);
+
   /// Borrow a new message.
   /** \return Shared pointer to the fresh message. */
   RCLCPP_PUBLIC
@@ -121,7 +166,7 @@ public:
   /** \return Shared pointer to a rcl_message_serialized_t. */
   RCLCPP_PUBLIC
   virtual
-  std::shared_ptr<rcl_serialized_message_t>
+  std::shared_ptr<rclcpp::SerializedMessage>
   create_serialized_message() = 0;
 
   /// Check if we need to handle the message, and execute the callback if we do.
@@ -132,12 +177,12 @@ public:
   RCLCPP_PUBLIC
   virtual
   void
-  handle_message(std::shared_ptr<void> & message, const rmw_message_info_t & message_info) = 0;
+  handle_message(std::shared_ptr<void> & message, const rclcpp::MessageInfo & message_info) = 0;
 
   RCLCPP_PUBLIC
   virtual
   void
-  handle_loaned_message(void * loaned_message, const rmw_message_info_t & message_info) = 0;
+  handle_loaned_message(void * loaned_message, const rclcpp::MessageInfo & message_info) = 0;
 
   /// Return the message borrowed in create_message.
   /** \param[in] message Shared pointer to the returned message. */
@@ -151,12 +196,16 @@ public:
   RCLCPP_PUBLIC
   virtual
   void
-  return_serialized_message(std::shared_ptr<rcl_serialized_message_t> & message) = 0;
+  return_serialized_message(std::shared_ptr<rclcpp::SerializedMessage> & message) = 0;
 
   RCLCPP_PUBLIC
   const rosidl_message_type_support_t &
   get_message_type_support_handle() const;
 
+  /// Return if the subscription is serialized
+  /**
+   * \return `true` if the subscription is serialized, `false` otherwise
+   */
   RCLCPP_PUBLIC
   bool
   is_serialized() const;
@@ -188,11 +237,32 @@ public:
     uint64_t intra_process_subscription_id,
     IntraProcessManagerWeakPtr weak_ipm);
 
-  /// Return the waitable for intra-process, or nullptr if intra-process is not setup.
+  /// Return the waitable for intra-process
+  /**
+   * \return the waitable sharedpointer for intra-process, or nullptr if intra-process is not setup.
+   * \throws std::runtime_error if the intra process manager is destroyed
+   */
   RCLCPP_PUBLIC
   rclcpp::Waitable::SharedPtr
   get_intra_process_waitable() const;
 
+  /// Exchange state of whether or not a part of the subscription is used by a wait set.
+  /**
+   * Used to ensure parts of the subscription are not used with multiple wait
+   * sets simultaneously.
+   *
+   * \param[in] pointer_to_subscription_part address of a subscription part
+   * \param[in] in_use_state the new state to exchange, true means "now in use",
+   *   and false means "no longer in use".
+   * \returns the current "in use" state.
+   * \throws std::invalid_argument If pointer_to_subscription_part is nullptr.
+   * \throws std::runtime_error If the pointer given is not a pointer to one of
+   *   the parts of the subscription which can be used with a wait set.
+   */
+  RCLCPP_PUBLIC
+  bool
+  exchange_in_use_by_wait_set_state(void * pointer_to_subscription_part, bool in_use_state);
+
 protected:
   template<typename EventCallbackT>
   void
@@ -200,14 +270,19 @@ protected:
     const EventCallbackT & callback,
     const rcl_subscription_event_type_t event_type)
   {
-    auto handler = std::make_shared<QOSEventHandler<EventCallbackT>>(
+    auto handler = std::make_shared<QOSEventHandler<EventCallbackT,
+        std::shared_ptr<rcl_subscription_t>>>(
       callback,
       rcl_subscription_event_init,
-      get_subscription_handle().get(),
+      get_subscription_handle(),
       event_type);
+    qos_events_in_use_by_wait_set_.insert(std::make_pair(handler.get(), false));
     event_handlers_.emplace_back(handler);
   }
 
+  RCLCPP_PUBLIC
+  void default_incompatible_qos_callback(QOSRequestedIncompatibleQoSInfo & info) const;
+
   RCLCPP_PUBLIC
   bool
   matches_any_intra_process_publishers(const rmw_gid_t * sender_gid) const;
@@ -229,6 +304,11 @@ private:
 
   rosidl_message_type_support_t type_support_;
   bool is_serialized_;
+
+  std::atomic<bool> subscription_in_use_by_wait_set_{false};
+  std::atomic<bool> intra_process_subscription_waitable_in_use_by_wait_set_{false};
+  std::unordered_map<rclcpp::QOSEventHandlerBase *,
+    std::atomic<bool>> qos_events_in_use_by_wait_set_;
 };
 
 }  // namespace rclcpp

rclcpp/include/rclcpp/subscription_factory.hpp

@@ -32,6 +32,7 @@
 #include "rclcpp/subscription_options.hpp"
 #include "rclcpp/subscription_traits.hpp"
 #include "rclcpp/visibility_control.hpp"
+#include "rclcpp/topic_statistics/subscription_topic_statistics.hpp"
 
 namespace rclcpp
 {
@@ -63,6 +64,12 @@ struct SubscriptionFactory
 };
 
 /// Return a SubscriptionFactory setup to create a SubscriptionT<MessageT, AllocatorT>.
+/**
+ * \param[in] callback The user-defined callback function to receive a message
+ * \param[in] options Additional options for the creation of the Subscription.
+ * \param[in] msg_mem_strat The message memory strategy to use for allocating messages.
+ * \param[in] subscription_topic_stats Optional stats callback for topic_statistics
+ */
 template<
   typename MessageT,
   typename CallbackT,
@@ -78,7 +85,10 @@ SubscriptionFactory
 create_subscription_factory(
   CallbackT && callback,
   const rclcpp::SubscriptionOptionsWithAllocator<AllocatorT> & options,
-  typename MessageMemoryStrategyT::SharedPtr msg_mem_strat)
+  typename MessageMemoryStrategyT::SharedPtr msg_mem_strat,
+  std::shared_ptr<rclcpp::topic_statistics::SubscriptionTopicStatistics<CallbackMessageT>>
+  subscription_topic_stats = nullptr
+)
 {
   auto allocator = options.get_allocator();
 
@@ -88,7 +98,7 @@ create_subscription_factory(
 
   SubscriptionFactory factory {
     // factory function that creates a MessageT specific SubscriptionT
-    [options, msg_mem_strat, any_subscription_callback](
+    [options, msg_mem_strat, any_subscription_callback, subscription_topic_stats](
       rclcpp::node_interfaces::NodeBaseInterface * node_base,
       const std::string & topic_name,
       const rclcpp::QoS & qos
@@ -104,7 +114,8 @@ create_subscription_factory(
         qos,
         any_subscription_callback,
         options,
-        msg_mem_strat);
+        msg_mem_strat,
+        subscription_topic_stats);
       // This is used for setting up things like intra process comms which
       // require this->shared_from_this() which cannot be called from
       // the constructor.

rclcpp/include/rclcpp/subscription_options.hpp

@@ -15,6 +15,7 @@
 #ifndef RCLCPP__SUBSCRIPTION_OPTIONS_HPP_
 #define RCLCPP__SUBSCRIPTION_OPTIONS_HPP_
 
+#include <chrono>
 #include <memory>
 #include <string>
 #include <vector>
@@ -25,6 +26,7 @@
 #include "rclcpp/intra_process_setting.hpp"
 #include "rclcpp/qos.hpp"
 #include "rclcpp/qos_event.hpp"
+#include "rclcpp/topic_statistics_state.hpp"
 #include "rclcpp/visibility_control.hpp"
 
 namespace rclcpp
@@ -36,11 +38,14 @@ struct SubscriptionOptionsBase
   /// Callbacks for events related to this subscription.
   SubscriptionEventCallbacks event_callbacks;
 
+  /// Whether or not to use default callbacks when user doesn't supply any in event_callbacks
+  bool use_default_callbacks = true;
+
   /// True to ignore local publications.
   bool ignore_local_publications = false;
 
   /// The callback group for this subscription. NULL to use the default callback group.
-  rclcpp::callback_group::CallbackGroup::SharedPtr callback_group = nullptr;
+  rclcpp::CallbackGroup::SharedPtr callback_group = nullptr;
 
   /// Setting to explicitly set intraprocess communications.
   IntraProcessSetting use_intra_process_comm = IntraProcessSetting::NodeDefault;
@@ -51,6 +56,22 @@ struct SubscriptionOptionsBase
   /// Optional RMW implementation specific payload to be used during creation of the subscription.
   std::shared_ptr<rclcpp::detail::RMWImplementationSpecificSubscriptionPayload>
   rmw_implementation_payload = nullptr;
+
+  // Options to configure topic statistics collector in the subscription.
+  struct TopicStatisticsOptions
+  {
+    // Enable and disable topic statistics calculation and publication. Defaults to disabled.
+    TopicStatisticsState state = TopicStatisticsState::NodeDefault;
+
+    // Topic to which topic statistics get published when enabled. Defaults to /statistics.
+    std::string publish_topic = "/statistics";
+
+    // Topic statistics publication period in ms. Defaults to one second.
+    // Only values greater than zero are allowed.
+    std::chrono::milliseconds publish_period{std::chrono::seconds(1)};
+  };
+
+  TopicStatisticsOptions topic_stats_options;
 };
 
 /// Structure containing optional configuration for Subscriptions.
@@ -69,15 +90,16 @@ struct SubscriptionOptionsWithAllocator : public SubscriptionOptionsBase
   {}
 
   /// Convert this class, with a rclcpp::QoS, into an rcl_subscription_options_t.
+  /**
+   * \param qos QoS profile for subcription.
+   * \return rcl_subscription_options_t structure based on the rclcpp::QoS
+   */
   template<typename MessageT>
   rcl_subscription_options_t
   to_rcl_subscription_options(const rclcpp::QoS & qos) const
   {
     rcl_subscription_options_t result = rcl_subscription_get_default_options();
-    using AllocatorTraits = std::allocator_traits<Allocator>;
-    using MessageAllocatorT = typename AllocatorTraits::template rebind_alloc<MessageT>;
-    auto message_alloc = std::make_shared<MessageAllocatorT>(*allocator.get());
-    result.allocator = allocator::get_rcl_allocator<MessageT>(*message_alloc);
+    result.allocator = this->get_rcl_allocator();
     result.qos = qos.get_rmw_qos_profile();
     result.rmw_subscription_options.ignore_local_publications = this->ignore_local_publications;
 
@@ -98,10 +120,31 @@ struct SubscriptionOptionsWithAllocator : public SubscriptionOptionsBase
     }
     return this->allocator;
   }
+
+private:
+  using PlainAllocator =
+    typename std::allocator_traits<Allocator>::template rebind_alloc<char>;
+
+  rcl_allocator_t
+  get_rcl_allocator() const
+  {
+    if (!plain_allocator_storage_) {
+      plain_allocator_storage_ =
+        std::make_shared<PlainAllocator>(*this->get_allocator());
+    }
+    return rclcpp::allocator::get_rcl_allocator<char>(*plain_allocator_storage_);
+  }
+
+  // This is a temporal workaround, to make sure that get_allocator()
+  // always returns a copy of the same allocator.
+  mutable std::shared_ptr<Allocator> allocator_storage_;
+
+  // This is a temporal workaround, to keep the plain allocator that backs
+  // up the rcl allocator returned in rcl_subscription_options_t alive.
+  mutable std::shared_ptr<PlainAllocator> plain_allocator_storage_;
 };
 
 using SubscriptionOptions = SubscriptionOptionsWithAllocator<std::allocator<void>>;
-
 }  // namespace rclcpp
 
 #endif  // RCLCPP__SUBSCRIPTION_OPTIONS_HPP_

rclcpp/include/rclcpp/subscription_traits.hpp

@@ -18,6 +18,8 @@
 #include <memory>
 
 #include "rclcpp/function_traits.hpp"
+#include "rclcpp/serialized_message.hpp"
+#include "rclcpp/subscription_options.hpp"
 #include "rcl/types.h"
 
 namespace rclcpp
@@ -41,11 +43,11 @@ struct is_serialized_subscription_argument : std::false_type
 {};
 
 template<>
-struct is_serialized_subscription_argument<rcl_serialized_message_t>: std::true_type
+struct is_serialized_subscription_argument<SerializedMessage>: std::true_type
 {};
 
 template<>
-struct is_serialized_subscription_argument<std::shared_ptr<rcl_serialized_message_t>>
+struct is_serialized_subscription_argument<std::shared_ptr<SerializedMessage>>
   : std::true_type
 {};
 
@@ -75,6 +77,7 @@ struct extract_message_type<std::unique_ptr<MessageT, Deleter>>: extract_message
 
 template<
   typename CallbackT,
+  typename AllocatorT = std::allocator<void>,
   // Do not attempt if CallbackT is an integer (mistaken for depth)
   typename = std::enable_if_t<!std::is_integral<
     std::remove_cv_t<std::remove_reference_t<CallbackT>>>::value>,
@@ -85,6 +88,10 @@ template<
   // Do not attempt if CallbackT is a rmw_qos_profile_t (mistaken for qos profile)
   typename = std::enable_if_t<!std::is_same<
     rmw_qos_profile_t,
+    std::remove_cv_t<std::remove_reference_t<CallbackT>>>::value>,
+  // Do not attempt if CallbackT is a rclcpp::SubscriptionOptionsWithAllocator
+  typename = std::enable_if_t<!std::is_same<
+    rclcpp::SubscriptionOptionsWithAllocator<AllocatorT>,
     std::remove_cv_t<std::remove_reference_t<CallbackT>>>::value>
 >
 struct has_message_type : extract_message_type<

rclcpp/include/rclcpp/subscription_wait_set_mask.hpp

@@ -0,0 +1,37 @@
+// Copyright 2020 Open Source Robotics Foundation, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef RCLCPP__SUBSCRIPTION_WAIT_SET_MASK_HPP_
+#define RCLCPP__SUBSCRIPTION_WAIT_SET_MASK_HPP_
+
+#include "rclcpp/visibility_control.hpp"
+
+namespace rclcpp
+{
+
+/// Options used to determine what parts of a subscription get added to or removed from a wait set.
+class RCLCPP_PUBLIC SubscriptionWaitSetMask
+{
+public:
+  /// If true, include the actual subscription.
+  bool include_subscription = true;
+  /// If true, include any events attached to the subscription.
+  bool include_events = true;
+  /// If true, include the waitable used to handle intra process communication.
+  bool include_intra_process_waitable = true;
+};
+
+}  // namespace rclcpp
+
+#endif  // RCLCPP__SUBSCRIPTION_WAIT_SET_MASK_HPP_

rclcpp/include/rclcpp/time.hpp

@@ -31,37 +31,78 @@ class Clock;
 class Time
 {
 public:
+  /// Time constructor
+  /**
+   * Initializes the time values for seconds and nanoseconds individually.
+   * Large values for nanoseconds are wrapped automatically with the remainder added to seconds.
+   * Both inputs must be integers.
+   *
+   * \param seconds part of the time in seconds since time epoch
+   * \param nanoseconds part of the time in nanoseconds since time epoch
+   * \param clock_type clock type
+   * \throws std::runtime_error if seconds are negative
+   */
   RCLCPP_PUBLIC
   Time(int32_t seconds, uint32_t nanoseconds, rcl_clock_type_t clock_type = RCL_SYSTEM_TIME);
 
+  /// Time constructor
+  /**
+   * \param nanoseconds since time epoch
+   * \param clock_type clock type
+   */
   RCLCPP_PUBLIC
-  explicit Time(int64_t nanoseconds = 0, rcl_clock_type_t clock = RCL_SYSTEM_TIME);
+  explicit Time(int64_t nanoseconds = 0, rcl_clock_type_t clock_type = RCL_SYSTEM_TIME);
 
+  /// Copy constructor
   RCLCPP_PUBLIC
   Time(const Time & rhs);
 
+  /// Time constructor
+  /**
+   * \param time_msg builtin_interfaces time message to copy
+   * \param clock_type clock type
+   * \throws std::runtime_error if seconds are negative
+   */
   RCLCPP_PUBLIC
   Time(
     const builtin_interfaces::msg::Time & time_msg,
-    rcl_clock_type_t ros_time = RCL_ROS_TIME);
+    rcl_clock_type_t clock_type = RCL_ROS_TIME);
 
+  /// Time constructor
+  /**
+   * \param time_point rcl_time_point_t structure to copy
+   */
   RCLCPP_PUBLIC
   explicit Time(const rcl_time_point_t & time_point);
 
+  /// Time destructor
   RCLCPP_PUBLIC
   virtual ~Time();
 
+  /// Return a builtin_interfaces::msg::Time object based
   RCLCPP_PUBLIC
   operator builtin_interfaces::msg::Time() const;
 
+  /**
+   * \throws std::runtime_error if seconds are negative
+   */
   RCLCPP_PUBLIC
   Time &
   operator=(const Time & rhs);
 
+  /**
+   * Assign Time from a builtin_interfaces::msg::Time instance.
+   * The clock_type will be reset to RCL_ROS_TIME.
+   * Equivalent to *this = Time(time_msg, RCL_ROS_TIME).
+   * \throws std::runtime_error if seconds are negative
+   */
   RCLCPP_PUBLIC
   Time &
   operator=(const builtin_interfaces::msg::Time & time_msg);
 
+  /**
+   * \throws std::runtime_error if the time sources are different
+   */
   RCLCPP_PUBLIC
   bool
   operator==(const rclcpp::Time & rhs) const;
@@ -70,49 +111,101 @@ public:
   bool
   operator!=(const rclcpp::Time & rhs) const;
 
+  /**
+   * \throws std::runtime_error if the time sources are different
+   */
   RCLCPP_PUBLIC
   bool
   operator<(const rclcpp::Time & rhs) const;
 
+  /**
+   * \throws std::runtime_error if the time sources are different
+   */
   RCLCPP_PUBLIC
   bool
   operator<=(const rclcpp::Time & rhs) const;
 
+  /**
+   * \throws std::runtime_error if the time sources are different
+   */
   RCLCPP_PUBLIC
   bool
   operator>=(const rclcpp::Time & rhs) const;
 
+  /**
+   * \throws std::runtime_error if the time sources are different
+   */
   RCLCPP_PUBLIC
   bool
   operator>(const rclcpp::Time & rhs) const;
 
+  /**
+   * \throws std::overflow_error if addition leads to overflow
+   */
   RCLCPP_PUBLIC
   Time
   operator+(const rclcpp::Duration & rhs) const;
 
+  /**
+   * \throws std::runtime_error if the time sources are different
+   * \throws std::overflow_error if addition leads to overflow
+   */
   RCLCPP_PUBLIC
   Duration
   operator-(const rclcpp::Time & rhs) const;
 
+  /**
+   * \throws std::overflow_error if addition leads to overflow
+   */
   RCLCPP_PUBLIC
   Time
   operator-(const rclcpp::Duration & rhs) const;
 
+  /**
+   * \throws std::overflow_error if addition leads to overflow
+   */
+  RCLCPP_PUBLIC
+  Time &
+  operator+=(const rclcpp::Duration & rhs);
+
+  /**
+   * \throws std::overflow_error if addition leads to overflow
+   */
+  RCLCPP_PUBLIC
+  Time &
+  operator-=(const rclcpp::Duration & rhs);
+
+  /// Get the nanoseconds since epoch
+  /**
+   * \return the nanoseconds since epoch as a rcl_time_point_value_t structure.
+   */
   RCLCPP_PUBLIC
   rcl_time_point_value_t
   nanoseconds() const;
 
+  /// Get the maximum representable value.
+  /**
+   * \return the maximum representable value
+   */
   RCLCPP_PUBLIC
   static Time
   max();
 
-  /// \return the seconds since epoch as a floating point number.
-  /// \warning Depending on sizeof(double) there could be significant precision loss.
-  /// When an exact time is required use nanoseconds() instead.
+  /// Get the seconds since epoch
+  /**
+   * \warning Depending on sizeof(double) there could be significant precision loss.
+   * When an exact time is required use nanoseconds() instead.
+   *
+   * \return the seconds since epoch as a floating point number.
+   */
   RCLCPP_PUBLIC
   double
   seconds() const;
 
+  /// Get the clock type
+  /**
+   * \return the clock type
+   */
   RCLCPP_PUBLIC
   rcl_clock_type_t
   get_clock_type() const;
@@ -122,6 +215,10 @@ private:
   friend Clock;  // Allow clock to manipulate internal data
 };
 
+/**
+ * \throws std::overflow_error if addition leads to overflow
+ */
+RCLCPP_PUBLIC
 Time
 operator+(const rclcpp::Duration & lhs, const rclcpp::Time & rhs);
 

rclcpp/include/rclcpp/time_source.hpp

@@ -35,15 +35,42 @@ class Clock;
 class TimeSource
 {
 public:
+  /// Constructor
+  /**
+   * The node will be attached to the time source.
+   *
+   * \param node std::shared pointer to a initialized node
+   */
   RCLCPP_PUBLIC
   explicit TimeSource(rclcpp::Node::SharedPtr node);
 
+  /// Empty constructor
+  /**
+   * An Empty TimeSource class
+   */
   RCLCPP_PUBLIC
   TimeSource();
 
+  /// Attack node to the time source.
+  /**
+   * \param node std::shared pointer to a initialized node
+   */
   RCLCPP_PUBLIC
   void attachNode(rclcpp::Node::SharedPtr node);
 
+  /// Attack node to the time source.
+  /**
+   * If the parameter `use_sim_time` is `true` then the source time is the simulation time,
+   * otherwise the source time is defined by the system.
+   *
+   * \param node_base_interface Node base interface.
+   * \param node_topics_interface Node topic base interface.
+   * \param node_graph_interface Node graph interface.
+   * \param node_services_interface Node service interface.
+   * \param node_logging_interface Node logging interface.
+   * \param node_clock_interface Node clock interface.
+   * \param node_parameters_interface Node parameters interface.
+   */
   RCLCPP_PUBLIC
   void attachNode(
     rclcpp::node_interfaces::NodeBaseInterface::SharedPtr node_base_interface,
@@ -54,19 +81,23 @@ public:
     rclcpp::node_interfaces::NodeClockInterface::SharedPtr node_clock_interface,
     rclcpp::node_interfaces::NodeParametersInterface::SharedPtr node_parameters_interface);
 
+  /// Detach the node from the time source
   RCLCPP_PUBLIC
   void detachNode();
 
   /// Attach a clock to the time source to be updated
   /**
-   * \throws std::invalid_argument if node is nullptr
+   * \param[in] clock to attach to the time source
+   * \throws std::invalid_argument the time source must be a RCL_ROS_TIME otherwise throws an exception
    */
   RCLCPP_PUBLIC
   void attachClock(rclcpp::Clock::SharedPtr clock);
 
+  /// Detach a clock to the time source
   RCLCPP_PUBLIC
   void detachClock(rclcpp::Clock::SharedPtr clock);
 
+  /// TimeSource Destructor
   RCLCPP_PUBLIC
   ~TimeSource();
 
@@ -117,8 +148,6 @@ private:
   void disable_ros_time();
 
   // Internal helper functions used inside iterators
-  static void enable_ros_time(rclcpp::Clock::SharedPtr clock);
-  static void disable_ros_time(rclcpp::Clock::SharedPtr clock);
   static void set_clock(
     const builtin_interfaces::msg::Time::SharedPtr msg,
     bool set_ros_time_enabled,

rclcpp/include/rclcpp/timer.hpp

@@ -15,6 +15,7 @@
 #ifndef RCLCPP__TIMER_HPP_
 #define RCLCPP__TIMER_HPP_
 
+#include <atomic>
 #include <chrono>
 #include <functional>
 #include <memory>
@@ -47,15 +48,27 @@ class TimerBase
 public:
   RCLCPP_SMART_PTR_DEFINITIONS_NOT_COPYABLE(TimerBase)
 
+  /// TimerBase constructor
+  /**
+   * \param clock A clock to use for time and sleeping
+   * \param period The interval at which the timer fires
+   * \param context node context
+   */
   RCLCPP_PUBLIC
   explicit TimerBase(
     Clock::SharedPtr clock,
     std::chrono::nanoseconds period,
     rclcpp::Context::SharedPtr context);
 
+  /// TimerBase destructor
   RCLCPP_PUBLIC
+  virtual
   ~TimerBase();
 
+  /// Cancel the timer.
+  /**
+   * \throws std::runtime_error if the rcl_timer_cancel returns a failure
+   */
   RCLCPP_PUBLIC
   void
   cancel();
@@ -64,16 +77,21 @@ public:
   /**
    * \return true if the timer has been cancelled, false otherwise
    * \throws std::runtime_error if the rcl_get_error_state returns 0
-   * \throws RCLErrorBase some child class exception based on ret
+   * \throws rclcpp::exceptions::RCLError some child class exception based on ret
    */
   RCLCPP_PUBLIC
   bool
   is_canceled();
 
+  /// Reset the timer.
+  /**
+   * \throws std::runtime_error if the rcl_timer_reset returns a failure
+   */
   RCLCPP_PUBLIC
   void
   reset();
 
+  /// Call the callback function when the timer signal is emitted.
   RCLCPP_PUBLIC
   virtual void
   execute_callback() = 0;
@@ -83,7 +101,10 @@ public:
   get_timer_handle();
 
   /// Check how long the timer has until its next scheduled callback.
-  /** \return A std::chrono::duration representing the relative time until the next callback. */
+  /**
+   * \return A std::chrono::duration representing the relative time until the next callback.
+   * \throws std::runtime_error if the rcl_timer_get_time_until_next_call returns a failure
+   */
   RCLCPP_PUBLIC
   std::chrono::nanoseconds
   time_until_trigger();
@@ -97,13 +118,30 @@ public:
    * This function expects its caller to immediately trigger the callback after this function,
    * since it maintains the last time the callback was triggered.
    * \return True if the timer needs to trigger.
+   * \throws std::runtime_error if it failed to check timer
    */
   RCLCPP_PUBLIC
   bool is_ready();
 
+  /// 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.
+   *
+   * \param[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.
+   */
+  RCLCPP_PUBLIC
+  bool
+  exchange_in_use_by_wait_set_state(bool in_use_state);
+
 protected:
   Clock::SharedPtr clock_;
   std::shared_ptr<rcl_timer_t> timer_handle_;
+
+  std::atomic<bool> in_use_by_wait_set_{false};
 };
 
 
@@ -128,6 +166,7 @@ public:
    * \param[in] clock The clock providing the current time.
    * \param[in] period The interval at which the timer fires.
    * \param[in] callback User-specified callback function.
+   * \param[in] context custom context to be used.
    */
   explicit GenericTimer(
     Clock::SharedPtr clock, std::chrono::nanoseconds period, FunctorT && callback,
@@ -152,6 +191,10 @@ public:
     cancel();
   }
 
+  /**
+   * \sa rclcpp::TimerBase::execute_callback
+   * \throws std::runtime_error if it failed to notify timer that callback occurred
+   */
   void
   execute_callback() override
   {
@@ -192,6 +235,8 @@ public:
     callback_(*this);
   }
 
+  /// Is the clock steady (i.e. is the time between ticks constant?)
+  /** \return True if the clock used by this timer is steady. */
   bool
   is_steady() override
   {
@@ -216,6 +261,12 @@ class WallTimer : public GenericTimer<FunctorT>
 public:
   RCLCPP_SMART_PTR_DEFINITIONS(WallTimer)
 
+  /// Wall timer constructor
+  /**
+   * \param period The interval at which the timer fires
+   * \param callback The callback function to execute every interval
+   * \param context node context
+   */
   WallTimer(
     std::chrono::nanoseconds period,
     FunctorT && callback,

rclcpp/include/rclcpp/topic_statistics/subscription_topic_statistics.hpp

@@ -0,0 +1,244 @@
+// Copyright 2020 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef RCLCPP__TOPIC_STATISTICS__SUBSCRIPTION_TOPIC_STATISTICS_HPP_
+#define RCLCPP__TOPIC_STATISTICS__SUBSCRIPTION_TOPIC_STATISTICS_HPP_
+
+#include <memory>
+#include <string>
+#include <utility>
+#include <vector>
+
+#include "libstatistics_collector/collector/generate_statistics_message.hpp"
+#include "libstatistics_collector/moving_average_statistics/types.hpp"
+#include "libstatistics_collector/topic_statistics_collector/constants.hpp"
+#include "libstatistics_collector/topic_statistics_collector/received_message_age.hpp"
+#include "libstatistics_collector/topic_statistics_collector/received_message_period.hpp"
+
+#include "rcl/time.h"
+#include "rclcpp/time.hpp"
+#include "rclcpp/publisher.hpp"
+#include "rclcpp/timer.hpp"
+
+#include "statistics_msgs/msg/metrics_message.hpp"
+
+namespace rclcpp
+{
+namespace topic_statistics
+{
+
+constexpr const char kDefaultPublishTopicName[]{"/statistics"};
+constexpr const std::chrono::milliseconds kDefaultPublishingPeriod{std::chrono::seconds(1)};
+
+using libstatistics_collector::collector::GenerateStatisticMessage;
+using statistics_msgs::msg::MetricsMessage;
+using libstatistics_collector::moving_average_statistics::StatisticData;
+
+/**
+ * Class used to collect, measure, and publish topic statistics data. Current statistics
+ * supported for subscribers are received message age and received message period.
+ *
+ * \tparam CallbackMessageT the subscribed message type
+ */
+template<typename CallbackMessageT>
+class SubscriptionTopicStatistics
+{
+  using TopicStatsCollector =
+    libstatistics_collector::topic_statistics_collector::TopicStatisticsCollector<
+    CallbackMessageT>;
+  using ReceivedMessageAge =
+    libstatistics_collector::topic_statistics_collector::ReceivedMessageAgeCollector<
+    CallbackMessageT>;
+  using ReceivedMessagePeriod =
+    libstatistics_collector::topic_statistics_collector::ReceivedMessagePeriodCollector<
+    CallbackMessageT>;
+
+public:
+  /// Construct a SubscriptionTopicStatistics object.
+  /**
+   * This object wraps utilities, defined in libstatistics_collector, to collect,
+   * measure, and publish topic statistics data. This throws an invalid_argument
+   * if the input publisher is null.
+   *
+   * \param node_name the name of the node, which created this instance, in order to denote
+   * topic source
+   * \param publisher instance constructed by the node in order to publish statistics data.
+   * This class owns the publisher.
+   * \throws std::invalid_argument if publisher pointer is nullptr
+   */
+  SubscriptionTopicStatistics(
+    const std::string & node_name,
+    rclcpp::Publisher<statistics_msgs::msg::MetricsMessage>::SharedPtr publisher)
+  : node_name_(node_name),
+    publisher_(std::move(publisher))
+  {
+    // TODO(dbbonnie): ros-tooling/aws-roadmap/issues/226, received message age
+
+    if (nullptr == publisher_) {
+      throw std::invalid_argument("publisher pointer is nullptr");
+    }
+
+    bring_up();
+  }
+
+  virtual ~SubscriptionTopicStatistics()
+  {
+    tear_down();
+  }
+
+  /// Handle a message received by the subscription to collect statistics.
+  /**
+   * This method acquires a lock to prevent race conditions to collectors list.
+   *
+   * \param received_message the message received by the subscription
+   * \param now_nanoseconds current time in nanoseconds
+   */
+  virtual void handle_message(
+    const CallbackMessageT & received_message,
+    const rclcpp::Time now_nanoseconds) const
+  {
+    std::lock_guard<std::mutex> lock(mutex_);
+    for (const auto & collector : subscriber_statistics_collectors_) {
+      collector->OnMessageReceived(received_message, now_nanoseconds.nanoseconds());
+    }
+  }
+
+  /// Set the timer used to publish statistics messages.
+  /**
+   * \param publisher_timer the timer to fire the publisher, created by the node
+   */
+  void set_publisher_timer(rclcpp::TimerBase::SharedPtr publisher_timer)
+  {
+    publisher_timer_ = publisher_timer;
+  }
+
+  /// Publish a populated MetricsStatisticsMessage.
+  /**
+   * This method acquires a lock to prevent race conditions to collectors list.
+   */
+  virtual void publish_message()
+  {
+    std::vector<MetricsMessage> msgs;
+    rclcpp::Time window_end{get_current_nanoseconds_since_epoch()};
+
+    {
+      std::lock_guard<std::mutex> lock(mutex_);
+      for (auto & collector : subscriber_statistics_collectors_) {
+        const auto collected_stats = collector->GetStatisticsResults();
+
+        auto message = libstatistics_collector::collector::GenerateStatisticMessage(
+          node_name_,
+          collector->GetMetricName(),
+          collector->GetMetricUnit(),
+          window_start_,
+          window_end,
+          collected_stats);
+        msgs.push_back(message);
+      }
+    }
+
+    for (auto & msg : msgs) {
+      publisher_->publish(msg);
+    }
+    window_start_ = window_end;
+  }
+
+protected:
+  /// Return a vector of all the currently collected data.
+  /**
+   * This method acquires a lock to prevent race conditions to collectors list.
+   *
+   * \return a vector of all the collected data
+   */
+  std::vector<StatisticData> get_current_collector_data() const
+  {
+    std::vector<StatisticData> data;
+    std::lock_guard<std::mutex> lock(mutex_);
+    for (const auto & collector : subscriber_statistics_collectors_) {
+      data.push_back(collector->GetStatisticsResults());
+    }
+    return data;
+  }
+
+private:
+  /// Construct and start all collectors and set window_start_.
+  /**
+   * This method acquires a lock to prevent race conditions to collectors list.
+   */
+  void bring_up()
+  {
+    auto received_message_age = std::make_unique<ReceivedMessageAge>();
+    received_message_age->Start();
+    subscriber_statistics_collectors_.emplace_back(std::move(received_message_age));
+
+    auto received_message_period = std::make_unique<ReceivedMessagePeriod>();
+    received_message_period->Start();
+    {
+      std::lock_guard<std::mutex> lock(mutex_);
+      subscriber_statistics_collectors_.emplace_back(std::move(received_message_period));
+    }
+
+    window_start_ = rclcpp::Time(get_current_nanoseconds_since_epoch());
+  }
+
+  /// Stop all collectors, clear measurements, stop publishing timer, and reset publisher.
+  /**
+   * This method acquires a lock to prevent race conditions to collectors list.
+   */
+  void tear_down()
+  {
+    {
+      std::lock_guard<std::mutex> lock(mutex_);
+      for (auto & collector : subscriber_statistics_collectors_) {
+        collector->Stop();
+      }
+
+      subscriber_statistics_collectors_.clear();
+    }
+
+    if (publisher_timer_) {
+      publisher_timer_->cancel();
+      publisher_timer_.reset();
+    }
+
+    publisher_.reset();
+  }
+
+  /// Return the current nanoseconds (count) since epoch.
+  /**
+   * \return the current nanoseconds (count) since epoch
+   */
+  int64_t get_current_nanoseconds_since_epoch() const
+  {
+    const auto now = std::chrono::system_clock::now();
+    return std::chrono::duration_cast<std::chrono::nanoseconds>(now.time_since_epoch()).count();
+  }
+
+  /// Mutex to protect the subsequence vectors
+  mutable std::mutex mutex_;
+  /// Collection of statistics collectors
+  std::vector<std::unique_ptr<TopicStatsCollector>> subscriber_statistics_collectors_{};
+  /// Node name used to generate topic statistics messages to be published
+  const std::string node_name_;
+  /// Publisher, created by the node, used to publish topic statistics messages
+  rclcpp::Publisher<statistics_msgs::msg::MetricsMessage>::SharedPtr publisher_;
+  /// Timer which fires the publisher
+  rclcpp::TimerBase::SharedPtr publisher_timer_;
+  /// The start of the collection window, used in the published topic statistics message
+  rclcpp::Time window_start_;
+};
+}  // namespace topic_statistics
+}  // namespace rclcpp
+
+#endif  // RCLCPP__TOPIC_STATISTICS__SUBSCRIPTION_TOPIC_STATISTICS_HPP_

rclcpp/include/rclcpp/topic_statistics_state.hpp

@@ -0,0 +1,35 @@
+// Copyright 2019 Open Source Robotics Foundation, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef RCLCPP__TOPIC_STATISTICS_STATE_HPP_
+#define RCLCPP__TOPIC_STATISTICS_STATE_HPP_
+
+namespace rclcpp
+{
+
+/// Represent the state of topic statistics collector.
+/// Used as argument in create_subscriber.
+enum class TopicStatisticsState
+{
+  /// Explicitly enable topic statistics at subscription level.
+  Enable,
+  /// Explicitly disable topic statistics at subscription level.
+  Disable,
+  /// Take topic statistics state from the node.
+  NodeDefault
+};
+
+}  // namespace rclcpp
+
+#endif  // RCLCPP__TOPIC_STATISTICS_STATE_HPP_

rclcpp/include/rclcpp/type_support_decl.hpp

@@ -15,8 +15,8 @@
 #ifndef RCLCPP__TYPE_SUPPORT_DECL_HPP_
 #define RCLCPP__TYPE_SUPPORT_DECL_HPP_
 
-#include "rosidl_generator_cpp/message_type_support_decl.hpp"
-#include "rosidl_generator_cpp/service_type_support_decl.hpp"
+#include "rosidl_runtime_cpp/message_type_support_decl.hpp"
+#include "rosidl_runtime_cpp/service_type_support_decl.hpp"
 
 #include "rosidl_typesupport_cpp/message_type_support.hpp"
 #include "rosidl_typesupport_cpp/service_type_support.hpp"

rclcpp/include/rclcpp/utilities.hpp

@@ -45,7 +45,7 @@ namespace rclcpp
 /// Initialize communications via the rmw implementation and set up a global signal handler.
 /**
  * Initializes the global context which is accessible via the function
- * rclcpp::contexts::default_context::get_global_default_context().
+ * rclcpp::contexts::get_global_default_context().
  * Also, installs the global signal handlers with the function
  * rclcpp::install_signal_handlers().
  *
@@ -121,7 +121,7 @@ init_and_remove_ros_arguments(
  * \param[in] argv Argument vector.
  * \returns Members of the argument vector that are not ROS arguments.
  * \throws anything throw_from_rcl_error can throw
- * \throws rclcpp::exceptions::RCLErrorBase if the parsing fails
+ * \throws rclcpp::exceptions::RCLError if the parsing fails
  */
 RCLCPP_PUBLIC
 std::vector<std::string>
@@ -136,7 +136,7 @@ remove_ros_arguments(int argc, char const * const argv[]);
  * If nullptr is given for the context, then the global context is used, i.e.
  * the context initialized by rclcpp::init().
  *
- * \param[in] context Check for shutdown of this Context.
+ * \param[in] context Optional check for shutdown of this Context.
  * \return true if shutdown has been called, false otherwise
  */
 RCLCPP_PUBLIC
@@ -150,9 +150,10 @@ ok(rclcpp::Context::SharedPtr context = nullptr);
  *
  * Deprecated, as it is no longer different from rcl_ok().
  *
- * \param[in] context Check for initialization of this Context.
+ * \param[in] context Optional check for initialization of this Context.
  * \return true if the context is initialized, and false otherwise
  */
+[[deprecated("use the function ok() instead, which has the same usage.")]]
 RCLCPP_PUBLIC
 bool
 is_initialized(rclcpp::Context::SharedPtr context = nullptr);
@@ -167,7 +168,8 @@ is_initialized(rclcpp::Context::SharedPtr context = nullptr);
  * This will also cause the "on_shutdown" callbacks to be called.
  *
  * \sa rclcpp::Context::shutdown()
- * \param[in] context to be shutdown
+ * \param[in] context Optional to be shutdown
+ * \param[in] reason Optional string passed to the context shutdown method
  * \return true if shutdown was successful, false if context was already shutdown
  */
 RCLCPP_PUBLIC
@@ -205,7 +207,7 @@ on_shutdown(std::function<void()> callback, rclcpp::Context::SharedPtr context =
  * the context initialized by rclcpp::init().
  *
  * \param[in] nanoseconds A std::chrono::duration representing how long to sleep for.
- * \param[in] context which may interrupt this sleep
+ * \param[in] context Optional which may interrupt this sleep
  * \return true if the condition variable did not timeout.
  */
 RCLCPP_PUBLIC

rclcpp/include/rclcpp/wait_for_message.hpp

@@ -0,0 +1,100 @@
+// Copyright 2021 Open Source Robotics Foundation, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef RCLCPP__WAIT_FOR_MESSAGE_HPP_
+#define RCLCPP__WAIT_FOR_MESSAGE_HPP_
+
+#include <memory>
+#include <string>
+
+#include "rclcpp/node.hpp"
+#include "rclcpp/visibility_control.hpp"
+#include "rclcpp/wait_set.hpp"
+
+namespace rclcpp
+{
+/// Wait for the next incoming message.
+/**
+ * Given an already initialized subscription,
+ * wait for the next incoming message to arrive before the specified timeout.
+ *
+ * \param[out] out is the message to be filled when a new message is arriving.
+ * \param[in] subscription shared pointer to a previously initialized subscription.
+ * \param[in] context shared pointer to a context to watch for SIGINT requests.
+ * \param[in] time_to_wait parameter specifying the timeout before returning.
+ * \return true if a message was successfully received, false if message could not
+ * be obtained or shutdown was triggered asynchronously on the context.
+ */
+template<class MsgT, class Rep = int64_t, class Period = std::milli>
+bool wait_for_message(
+  MsgT & out,
+  std::shared_ptr<rclcpp::Subscription<MsgT>> subscription,
+  std::shared_ptr<rclcpp::Context> context,
+  std::chrono::duration<Rep, Period> time_to_wait = std::chrono::duration<Rep, Period>(-1))
+{
+  auto gc = std::make_shared<rclcpp::GuardCondition>(context);
+  auto shutdown_callback = context->on_shutdown(
+    [weak_gc = std::weak_ptr<rclcpp::GuardCondition>{gc}]() {
+      auto strong_gc = weak_gc.lock();
+      if (strong_gc) {
+        strong_gc->trigger();
+      }
+    });
+
+  rclcpp::WaitSet wait_set;
+  wait_set.add_subscription(subscription);
+  wait_set.add_guard_condition(gc);
+  auto ret = wait_set.wait(time_to_wait);
+  if (ret.kind() != rclcpp::WaitResultKind::Ready) {
+    return false;
+  }
+
+  if (wait_set.get_rcl_wait_set().guard_conditions[0]) {
+    return false;
+  }
+
+  rclcpp::MessageInfo info;
+  if (!subscription->take(out, info)) {
+    return false;
+  }
+
+  return true;
+}
+
+/// Wait for the next incoming message.
+/**
+ * Wait for the next incoming message to arrive on a specified topic before the specified timeout.
+ *
+ * \param[out] out is the message to be filled when a new message is arriving.
+ * \param[in] node the node pointer to initialize the subscription on.
+ * \param[in] topic the topic to wait for messages.
+ * \param[in] time_to_wait parameter specifying the timeout before returning.
+ * \return true if a message was successfully received, false if message could not
+ * be obtained or shutdown was triggered asynchronously on the context.
+ */
+template<class MsgT, class Rep = int64_t, class Period = std::milli>
+bool wait_for_message(
+  MsgT & out,
+  rclcpp::Node::SharedPtr node,
+  const std::string & topic,
+  std::chrono::duration<Rep, Period> time_to_wait = std::chrono::duration<Rep, Period>(-1))
+{
+  auto sub = node->create_subscription<MsgT>(topic, 1, [](const std::shared_ptr<MsgT>) {});
+  return wait_for_message<MsgT, Rep, Period>(
+    out, sub, node->get_node_options().context(), time_to_wait);
+}
+
+}  // namespace rclcpp
+
+#endif  // RCLCPP__WAIT_FOR_MESSAGE_HPP_