Avoid unecessary creation of MultiThreadedExecutor (#3090) (#3096)

(cherry picked from commit 8cd4d47ec5)

Signed-off-by: solonovamax <solonovamax@12oclockpoint.com>
Co-authored-by: solo <solonovamax@12oclockpoint.com>

rclcpp/CHANGELOG.rst

@@ -2,6 +2,275 @@
 Changelog for package rclcpp
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
+16.0.18 (2026-02-09)
+--------------------
+* print warning message on owner node if the parameter operation fails. (backport `#3037 <https://github.com/ros2/rclcpp/issues/3037>`_) (`#3040 <https://github.com/ros2/rclcpp/issues/3040>`_)
+* fix context in wait for message wait set (`#3030 <https://github.com/ros2/rclcpp/issues/3030>`_) (`#3033 <https://github.com/ros2/rclcpp/issues/3033>`_)
+* Improve the robustness of the TopicEndpointInfo constructor (backport `#3013 <https://github.com/ros2/rclcpp/issues/3013>`_) (`#3016 <https://github.com/ros2/rclcpp/issues/3016>`_)
+* Contributors: mergify[bot]
+
+16.0.17 (2025-12-23)
+--------------------
+* Unified Node Interfaces: Add const version of get_node_x_interface() (`#3006 <https://github.com/ros2/rclcpp/issues/3006>`_) (`#3010 <https://github.com/ros2/rclcpp/issues/3010>`_)
+* [Humble] Implement Unified Node Interface (NodeInterfaces class) (backport `#2041 <https://github.com/ros2/rclcpp/issues/2041>`_) (`#3002 <https://github.com/ros2/rclcpp/issues/3002>`_)
+* remove I/O from signal handler. (`#3000 <https://github.com/ros2/rclcpp/issues/3000>`_) (`#3005 <https://github.com/ros2/rclcpp/issues/3005>`_)
+* correct test function descriptions (backport `#2970 <https://github.com/ros2/rclcpp/issues/2970>`_) (`#2994 <https://github.com/ros2/rclcpp/issues/2994>`_)
+* Contributors: fabianhirmann, mergify[bot]
+
+16.0.16 (2025-11-18)
+--------------------
+* Fix REP url locations (backport `#2987 <https://github.com/ros2/rclcpp/issues/2987>`_) (`#2991 <https://github.com/ros2/rclcpp/issues/2991>`_)
+* Contributors: mergify[bot]
+
+16.0.15 (2025-09-11)
+--------------------
+* Allow for implicitly convertable loggers as well (`#2922 <https://github.com/ros2/rclcpp/issues/2922>`_) (`#2936 <https://github.com/ros2/rclcpp/issues/2936>`_) (`#2938 <https://github.com/ros2/rclcpp/issues/2938>`_)
+* Fix: improve exception context for parameter_value_from (backport `#2917 <https://github.com/ros2/rclcpp/issues/2917>`_) (`#2921 <https://github.com/ros2/rclcpp/issues/2921>`_)
+* Removed warning test_qos (`#2859 <https://github.com/ros2/rclcpp/issues/2859>`_) (`#2925 <https://github.com/ros2/rclcpp/issues/2925>`_)
+* Add qos parameter for wait_for_message function (`#2903 <https://github.com/ros2/rclcpp/issues/2903>`_) (`#2907 <https://github.com/ros2/rclcpp/issues/2907>`_)
+* Contributors: mergify[bot]
+
+16.0.14 (2025-07-16)
+--------------------
+* fix test_publisher_with_system_default_qos. (backport `#2881 <https://github.com/ros2/rclcpp/issues/2881>`_) (`#2882 <https://github.com/ros2/rclcpp/issues/2882>`_)
+* Contributors: mergify[bot]
+
+16.0.13 (2025-06-23)
+--------------------
+* Fix for memory leaks in rclcpp::SerializedMessage (`#2861 <https://github.com/ros2/rclcpp/issues/2861>`_) (`#2865 <https://github.com/ros2/rclcpp/issues/2865>`_)
+* Added missing chrono includes (backport `#2854 <https://github.com/ros2/rclcpp/issues/2854>`_) (`#2857 <https://github.com/ros2/rclcpp/issues/2857>`_)
+* QoSInitialization::from_rmw does not validate invalid history policy … (backport `#2841 <https://github.com/ros2/rclcpp/issues/2841>`_) (`#2844 <https://github.com/ros2/rclcpp/issues/2844>`_)
+* throws std::invalid_argument if ParameterEvent is NULL. (`#2814 <https://github.com/ros2/rclcpp/issues/2814>`_) (`#2824 <https://github.com/ros2/rclcpp/issues/2824>`_)
+* remove redundant typesupport check in serialization module (`#2808 <https://github.com/ros2/rclcpp/issues/2808>`_) (`#2816 <https://github.com/ros2/rclcpp/issues/2816>`_)
+* Contributors: mergify[bot]
+
+16.0.12 (2025-03-25)
+--------------------
+* doc: Added warning to not instantiate Clock directly with RCL_ROS_TIME (`#2768 <https://github.com/ros2/rclcpp/issues/2768>`_) (`#2770 <https://github.com/ros2/rclcpp/issues/2770>`_)
+* apply actual QoS from rmw to the IPC publisher. (backport `#2707 <https://github.com/ros2/rclcpp/issues/2707>`_) (`#2711 <https://github.com/ros2/rclcpp/issues/2711>`_)
+* Adding in topic name to logging on IPC issues (`#2706 <https://github.com/ros2/rclcpp/issues/2706>`_) (`#2709 <https://github.com/ros2/rclcpp/issues/2709>`_)
+* Contributors: mergify[bot]
+
+16.0.11 (2024-11-25)
+--------------------
+* Fix subscription.is_serialized() for callbacks with message info (`#1950 <https://github.com/ros2/rclcpp/issues/1950>`_) (`#2622 <https://github.com/ros2/rclcpp/issues/2622>`_)
+* Use the same context for the specified node in rclcpp::spin functions… (`#2618 <https://github.com/ros2/rclcpp/issues/2618>`_) (`#2620 <https://github.com/ros2/rclcpp/issues/2620>`_)
+* Contributors: mergify[bot], roscan-tech
+
+16.0.10 (2024-07-26)
+--------------------
+* Add test creating two content filter topics with the same topic name (`#2546 <https://github.com/ros2/rclcpp/issues/2546>`_) (`#2549 <https://github.com/ros2/rclcpp/issues/2549>`_) (`#2551 <https://github.com/ros2/rclcpp/issues/2551>`_)
+* Contributors: mergify[bot]
+
+16.0.9 (2024-05-15)
+-------------------
+* Fix logging macros to build with msvc and cpp20 (`#2063 <https://github.com/ros2/rclcpp/issues/2063>`_) (`#2529 <https://github.com/ros2/rclcpp/issues/2529>`_)
+* address ambiguous auto variable. (`#2481 <https://github.com/ros2/rclcpp/issues/2481>`_) (`#2485 <https://github.com/ros2/rclcpp/issues/2485>`_)
+* Fix clang warning: bugprone-use-after-move (`#2116 <https://github.com/ros2/rclcpp/issues/2116>`_) (`#2459 <https://github.com/ros2/rclcpp/issues/2459>`_)
+* Contributors: Tamaki Nishino, mergify[bot]
+
+16.0.8 (2024-01-24)
+-------------------
+* Add missing stdexcept include (`#2186 <https://github.com/ros2/rclcpp/issues/2186>`_) (`#2394 <https://github.com/ros2/rclcpp/issues/2394>`_)
+* Contributors: gentoo90
+
+16.0.7 (2023-11-13)
+-------------------
+* Disable the loaned messages inside the executor. (backport `#2335 <https://github.com/ros2/rclcpp/issues/2335>`_) (`#2364 <https://github.com/ros2/rclcpp/issues/2364>`_)
+* Add missing 'enable_rosout' comments (`#2345 <https://github.com/ros2/rclcpp/issues/2345>`_) (`#2347 <https://github.com/ros2/rclcpp/issues/2347>`_)
+* address rate related flaky tests. (`#2329 <https://github.com/ros2/rclcpp/issues/2329>`_) (`#2342 <https://github.com/ros2/rclcpp/issues/2342>`_)
+* Update SignalHandler get_global_signal_handler to avoid complex types in static memory (`#2316 <https://github.com/ros2/rclcpp/issues/2316>`_) (`#2321 <https://github.com/ros2/rclcpp/issues/2321>`_)
+* Fix C++20 allocator construct deprecation (`#2292 <https://github.com/ros2/rclcpp/issues/2292>`_) (`#2319 <https://github.com/ros2/rclcpp/issues/2319>`_)
+* Contributors: mergify[bot]
+
+16.0.6 (2023-09-19)
+-------------------
+* Topic correct typeadapter deduction (`#2294 <https://github.com/ros2/rclcpp/issues/2294>`_) (`#2297 <https://github.com/ros2/rclcpp/issues/2297>`_)
+* check thread whether joinable before join (`#2019 <https://github.com/ros2/rclcpp/issues/2019>`_) (`#2275 <https://github.com/ros2/rclcpp/issues/2275>`_)
+* Do not crash Executor when send_response fails due to client failure. (`#2276 <https://github.com/ros2/rclcpp/issues/2276>`_) (`#2280 <https://github.com/ros2/rclcpp/issues/2280>`_)
+* Contributors: mergify[bot]
+
+16.0.5 (2023-07-17)
+-------------------
+* warning: comparison of integer expressions of different signedness (`#2219 <https://github.com/ros2/rclcpp/issues/2219>`_) (`#2223 <https://github.com/ros2/rclcpp/issues/2223>`_)
+* Trigger the intraprocess guard condition with data (`#2164 <https://github.com/ros2/rclcpp/issues/2164>`_) (`#2167 <https://github.com/ros2/rclcpp/issues/2167>`_)
+* Implement validity checks for rclcpp::Clock (`#2040 <https://github.com/ros2/rclcpp/issues/2040>`_) (`#2210 <https://github.com/ros2/rclcpp/issues/2210>`_)
+* Contributors: Tomoya Fujita, mergify[bot]
+
+16.0.4 (2023-04-25)
+-------------------
+* use allocator via init_options argument. (`#2129 <https://github.com/ros2/rclcpp/issues/2129>`_) (`#2131 <https://github.com/ros2/rclcpp/issues/2131>`_)
+* Contributors: mergify[bot]
+
+16.0.3 (2023-01-10)
+-------------------
+* Fix SharedFuture from async_send_request never becomes valid (`#2044 <https://github.com/ros2/rclcpp/issues/2044>`_) (`#2076 <https://github.com/ros2/rclcpp/issues/2076>`_)
+* do not throw exception if trying to dequeue an empty intra-process buffer (`#2061 <https://github.com/ros2/rclcpp/issues/2061>`_) (`#2070 <https://github.com/ros2/rclcpp/issues/2070>`_)
+* fix nullptr dereference in prune_requests_older_than (`#2008 <https://github.com/ros2/rclcpp/issues/2008>`_) (`#2065 <https://github.com/ros2/rclcpp/issues/2065>`_)
+* Fix bug that a callback not reached (`#1640 <https://github.com/ros2/rclcpp/issues/1640>`_) (`#2033 <https://github.com/ros2/rclcpp/issues/2033>`_)
+* Contributors: mergify[bot]
+
+16.0.2 (2022-11-07)
+-------------------
+* fix mismatched issue if using zero_allocate (`#1995 <https://github.com/ros2/rclcpp/issues/1995>`_) (`#2026 <https://github.com/ros2/rclcpp/issues/2026>`_)
+* use regex for wildcard matching (backport `#1839 <https://github.com/ros2/rclcpp/issues/1839>`_) (`#1986 <https://github.com/ros2/rclcpp/issues/1986>`_)
+* Drop wrong template specialization (`#1926 <https://github.com/ros2/rclcpp/issues/1926>`_) (`#1937 <https://github.com/ros2/rclcpp/issues/1937>`_)
+* Add statistics for handle_loaned_message (`#1927 <https://github.com/ros2/rclcpp/issues/1927>`_) (`#1932 <https://github.com/ros2/rclcpp/issues/1932>`_)
+* Contributors: mergify[bot]
+
+16.0.1 (2022-04-13)
+-------------------
+* remove DEFINE_CONTENT_FILTER cmake option (`#1914 <https://github.com/ros2/rclcpp/issues/1914>`_)
+* Contributors: Chen Lihui
+
+16.0.0 (2022-04-08)
+-------------------
+* remove things that were deprecated during galactic (`#1913 <https://github.com/ros2/rclcpp/issues/1913>`_)
+* Contributors: William Woodall
+
+15.4.0 (2022-04-05)
+-------------------
+* add take_data_by_entity_id API to waitable (`#1892 <https://github.com/ros2/rclcpp/issues/1892>`_)
+* add content-filtered-topic interfaces (`#1561 <https://github.com/ros2/rclcpp/issues/1561>`_)
+* Contributors: Alberto Soragna, Chen Lihui
+
+15.3.0 (2022-03-30)
+-------------------
+* [NodeParameters] Set name in param info pre-check (`#1908 <https://github.com/ros2/rclcpp/issues/1908>`_)
+* Add test-dep ament_cmake_google_benchmark (`#1904 <https://github.com/ros2/rclcpp/issues/1904>`_)
+* Add publish by loaned message in GenericPublisher (`#1856 <https://github.com/ros2/rclcpp/issues/1856>`_)
+* Contributors: Abrar Rahman Protyasha, Barry Xu, Gaël Écorchard
+
+15.2.0 (2022-03-24)
+-------------------
+* Add missing ament dependency on rcl_interfaces (`#1903 <https://github.com/ros2/rclcpp/issues/1903>`_)
+* Update data callback tests to account for all published samples (`#1900 <https://github.com/ros2/rclcpp/issues/1900>`_)
+* Increase timeout for acknowledgments to account for slower Connext settings (`#1901 <https://github.com/ros2/rclcpp/issues/1901>`_)
+* clang-tidy: explicit constructors (`#1782 <https://github.com/ros2/rclcpp/issues/1782>`_)
+* Add client/service QoS getters (`#1784 <https://github.com/ros2/rclcpp/issues/1784>`_)
+* Fix a bunch more rosdoc2 issues in rclcpp. (`#1897 <https://github.com/ros2/rclcpp/issues/1897>`_)
+* time_until_trigger returns max time if timer is cancelled (`#1893 <https://github.com/ros2/rclcpp/issues/1893>`_)
+* Micro-optimizations in rclcpp (`#1896 <https://github.com/ros2/rclcpp/issues/1896>`_)
+* Contributors: Andrea Sorbini, Chris Lalancette, Mauro Passerino, Scott K Logan, William Woodall
+
+15.1.0 (2022-03-01)
+-------------------
+* spin_all with a zero timeout. (`#1878 <https://github.com/ros2/rclcpp/issues/1878>`_)
+* Add RMW listener APIs (`#1579 <https://github.com/ros2/rclcpp/issues/1579>`_)
+* Remove fastrtps customization on tests (`#1887 <https://github.com/ros2/rclcpp/issues/1887>`_)
+* Install headers to include/${PROJECT_NAME} (`#1888 <https://github.com/ros2/rclcpp/issues/1888>`_)
+* Use ament_generate_version_header (`#1886 <https://github.com/ros2/rclcpp/issues/1886>`_)
+* use universal reference to support rvalue. (`#1883 <https://github.com/ros2/rclcpp/issues/1883>`_)
+* fix one subscription can wait_for_message twice (`#1870 <https://github.com/ros2/rclcpp/issues/1870>`_)
+* Add return value version of get_parameter_or (`#1813 <https://github.com/ros2/rclcpp/issues/1813>`_)
+* Cleanup time source object lifetimes (`#1867 <https://github.com/ros2/rclcpp/issues/1867>`_)
+* add is_spinning() method to executor base class
+* Contributors: Alberto Soragna, Chen Lihui, Chris Lalancette, Kenji Miyake, Miguel Company, Shane Loretz, Tomoya Fujita, iRobot ROS
+
+15.0.0 (2022-01-14)
+-------------------
+* Cleanup the TypeAdapt tests (`#1858 <https://github.com/ros2/rclcpp/issues/1858>`_)
+* Cleanup includes (`#1857 <https://github.com/ros2/rclcpp/issues/1857>`_)
+* Fix include order and relative paths for cpplint (`#1859 <https://github.com/ros2/rclcpp/issues/1859>`_)
+* Rename stringstream in macros to a more unique name (`#1862 <https://github.com/ros2/rclcpp/issues/1862>`_)
+* Add non transform capabilities for intra-process (`#1849 <https://github.com/ros2/rclcpp/issues/1849>`_)
+* Fix rclcpp documentation build (`#1779 <https://github.com/ros2/rclcpp/issues/1779>`_)
+* Contributors: Chris Lalancette, Doug Smith, Gonzo, Jacob Perron, Michel Hidalgo
+
+14.1.0 (2022-01-05)
+-------------------
+* Use UninitializedStaticallyTypedParameterException (`#1689 <https://github.com/ros2/rclcpp/issues/1689>`_)
+* Add wait_for_all_acked support (`#1662 <https://github.com/ros2/rclcpp/issues/1662>`_)
+* Add tests for function templates of declare_parameter (`#1747 <https://github.com/ros2/rclcpp/issues/1747>`_)
+* Contributors: Barry Xu, Bi0T1N, M. Mostafa Farzan
+
+14.0.0 (2021-12-17)
+-------------------
+* Fixes for uncrustify 0.72 (`#1844 <https://github.com/ros2/rclcpp/issues/1844>`_)
+* use private member to keep the all reference underneath. (`#1845 <https://github.com/ros2/rclcpp/issues/1845>`_)
+* Make node base sharable (`#1832 <https://github.com/ros2/rclcpp/issues/1832>`_)
+* Add Clock::sleep_for() (`#1828 <https://github.com/ros2/rclcpp/issues/1828>`_)
+* Synchronize rcl and std::chrono steady clocks in Clock::sleep_until (`#1830 <https://github.com/ros2/rclcpp/issues/1830>`_)
+* Use rclcpp::guard_condition (`#1612 <https://github.com/ros2/rclcpp/issues/1612>`_)
+* Call CMake function to generate version header (`#1805 <https://github.com/ros2/rclcpp/issues/1805>`_)
+* Use parantheses around logging macro parameter (`#1820 <https://github.com/ros2/rclcpp/issues/1820>`_)
+* Remove author by request (`#1818 <https://github.com/ros2/rclcpp/issues/1818>`_)
+* Update maintainers (`#1817 <https://github.com/ros2/rclcpp/issues/1817>`_)
+* min_forward & min_backward thresholds must not be disabled (`#1815 <https://github.com/ros2/rclcpp/issues/1815>`_)
+* Re-add Clock::sleep_until (`#1814 <https://github.com/ros2/rclcpp/issues/1814>`_)
+* Fix lifetime of context so it remains alive while its dependent node handles are still in use (`#1754 <https://github.com/ros2/rclcpp/issues/1754>`_)
+* Add the interface for pre-shutdown callback (`#1714 <https://github.com/ros2/rclcpp/issues/1714>`_)
+* Take message ownership from moved LoanedMessage (`#1808 <https://github.com/ros2/rclcpp/issues/1808>`_)
+* Suppress clang dead-store warnings in the benchmarks. (`#1802 <https://github.com/ros2/rclcpp/issues/1802>`_)
+* Wait for publisher and subscription to match (`#1777 <https://github.com/ros2/rclcpp/issues/1777>`_)
+* Fix unused QoS profile for clock subscription and make ClockQoS the default (`#1801 <https://github.com/ros2/rclcpp/issues/1801>`_)
+* Contributors: Abrar Rahman Protyasha, Barry Xu, Chen Lihui, Chris Lalancette, Grey, Jacob Perron, Nikolai Morin, Shane Loretz, Tomoya Fujita, mauropasse
+
+13.1.0 (2021-10-18)
+-------------------
+* Fix dangerous std::bind capture in TimeSource implementation. (`#1768 <https://github.com/ros2/rclcpp/issues/1768>`_)
+* Fix dangerous std::bind capture in ParameterEventHandler implementation. (`#1770 <https://github.com/ros2/rclcpp/issues/1770>`_)
+* Handle sigterm, in the same way sigint is being handled. (`#1771 <https://github.com/ros2/rclcpp/issues/1771>`_)
+* rclcpp::Node copy constructor: make copy of node_waitables\_ member. (`#1799 <https://github.com/ros2/rclcpp/issues/1799>`_)
+* Extend NodeGraph to match what rcl provides. (`#1484 <https://github.com/ros2/rclcpp/issues/1484>`_)
+* Context::sleep_for(): replace recursion with do-while to avoid potential stack-overflow. (`#1765 <https://github.com/ros2/rclcpp/issues/1765>`_)
+* extend_sub_namespace(): Verify string::empty() before calling string::front(). (`#1764 <https://github.com/ros2/rclcpp/issues/1764>`_)
+* Deprecate the `void shared_ptr<MessageT>` subscription callback signatures. (`#1713 <https://github.com/ros2/rclcpp/issues/1713>`_)
+* Contributors: Abrar Rahman Protyasha, Chris Lalancette, Emerson Knapp, Geoffrey Biggs, Ivan Santiago Paunovic, Jorge Perez, Tomoya Fujita, William Woodall, Yong-Hao Zou, livanov93
+
+13.0.0 (2021-08-23)
+-------------------
+* Remove can_be_nullptr assignment check for QNX case. (`#1752 <https://github.com/ros2/rclcpp/issues/1752>`_)
+* Update client API to be able to remove pending requests. (`#1734 <https://github.com/ros2/rclcpp/issues/1734>`_)
+* Fix: Allow to add a node while spinning in the StaticSingleThreadedExecutor. (`#1690 <https://github.com/ros2/rclcpp/issues/1690>`_)
+* Add tracing instrumentation for executor and message taking. (`#1738 <https://github.com/ros2/rclcpp/issues/1738>`_)
+* Fix: Reset timer trigger time before execute in StaticSingleThreadedExecutor. (`#1739 <https://github.com/ros2/rclcpp/issues/1739>`_)
+* Use FindPython3 and make python3 dependency explicit. (`#1745 <https://github.com/ros2/rclcpp/issues/1745>`_)
+* Use rosidl_get_typesupport_target(). (`#1729 <https://github.com/ros2/rclcpp/issues/1729>`_)
+* Fix returning invalid namespace if sub_namespace is empty. (`#1658 <https://github.com/ros2/rclcpp/issues/1658>`_)
+* Add free function to wait for a subscription message. (`#1705 <https://github.com/ros2/rclcpp/issues/1705>`_)
+* Use rcpputils/scope_exit.hpp and remove rclcpp/scope_exit.hpp. (`#1727 <https://github.com/ros2/rclcpp/issues/1727>`_)
+* Contributors: Ahmed Sobhy, Christophe Bedard, Ivan Santiago Paunovic, Karsten Knese, M. Hofstätter, Mauro Passerino, Shane Loretz, mauropasse
+
+12.0.0 (2021-07-26)
+-------------------
+* Remove unsafe get_callback_groups API.
+  Callers should change to using for_each_callback_group(), or
+  store the callback groups they need internally.
+* Add in callback_groups_for_each.
+  The main reason to add this method in is to make accesses to the
+  callback_groups\_ vector thread-safe.  By having a
+  callback_groups_for_each that accepts a std::function, we can
+  just have the callers give us the callback they are interested
+  in, and we can take care of the locking.
+  The rest of this fairly large PR is cleaning up all of the places
+  that use get_callback_groups() to instead use
+  callback_groups_for_each().
+* Use a different mechanism to avoid timers being scheduled multiple times by the MultiThreadedExecutor (`#1692 <https://github.com/ros2/rclcpp/issues/1692>`_)
+* Fix windows CI (`#1726 <https://github.com/ros2/rclcpp/issues/1726>`_)
+  Fix bug in AnyServiceCallback introduced in `#1709 <https://github.com/ros2/rclcpp/issues/1709>`_.
+* Contributors: Chris Lalancette, Ivan Santiago Paunovic
+
+11.2.0 (2021-07-21)
+-------------------
+* Support to defer to send a response in services. (`#1709 <https://github.com/ros2/rclcpp/issues/1709>`_)
+  Signed-off-by: Ivan Santiago Paunovic <ivanpauno@ekumenlabs.com>
+* Fix documentation bug. (`#1719 <https://github.com/ros2/rclcpp/issues/1719>`_)
+  Signed-off-by: William Woodall <william@osrfoundation.org>
+* Contributors: Ivan Santiago Paunovic, William Woodall
+
+11.1.0 (2021-07-13)
+-------------------
+* Removed left over ``is_initialized()`` implementation (`#1711 <https://github.com/ros2/rclcpp/issues/1711>`_)
+  Leftover from https://github.com/ros2/rclcpp/pull/1622
+* Fixed declare parameter methods for int and float vectors (`#1696 <https://github.com/ros2/rclcpp/issues/1696>`_)
+* Cleaned up implementation of the intra-process manager (`#1695 <https://github.com/ros2/rclcpp/issues/1695>`_)
+* Added the node name to an executor ``runtime_error`` (`#1686 <https://github.com/ros2/rclcpp/issues/1686>`_)
+* Fixed a typo "Attack" -> "Attach" (`#1687 <https://github.com/ros2/rclcpp/issues/1687>`_)
+* Removed use of std::allocator<>::rebind (`#1678 <https://github.com/ros2/rclcpp/issues/1678>`_)
+  rebind is deprecated in c++17 and removed in c++20
+* Contributors: Alberto Soragna, Chen Lihui, Chris Lalancette, Petter Nilsson, Steve Macenski, William Woodall
+
 11.0.0 (2021-05-18)
 -------------------
 * Allow declare uninitialized parameters (`#1673 <https://github.com/ros2/rclcpp/issues/1673>`_)

rclcpp/CMakeLists.txt

@@ -1,4 +1,4 @@
-cmake_minimum_required(VERSION 3.5)
+cmake_minimum_required(VERSION 3.12)
 
 project(rclcpp)
 
@@ -41,7 +41,7 @@ set(${PROJECT_NAME}_SRCS
   src/rclcpp/clock.cpp
   src/rclcpp/context.cpp
   src/rclcpp/contexts/default_context.cpp
-  src/rclcpp/detail/mutex_two_priorities.cpp
+  src/rclcpp/detail/add_guard_condition_to_rcl_wait_set.cpp
   src/rclcpp/detail/resolve_parameter_overrides.cpp
   src/rclcpp/detail/rmw_implementation_specific_payload.cpp
   src/rclcpp/detail/rmw_implementation_specific_publisher_payload.cpp
@@ -110,6 +110,8 @@ set(${PROJECT_NAME}_SRCS
   src/rclcpp/waitable.cpp
 )
 
+find_package(Python3 REQUIRED COMPONENTS Interpreter)
+
 # "watch" template for changes
 configure_file(
   "resource/logging.hpp.em"
@@ -123,7 +125,7 @@ set(python_code_logging
 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_logging}"
+  COMMAND Python3::Interpreter ARGS -c "${python_code_logging}"
   DEPENDS "${CMAKE_CURRENT_BINARY_DIR}/logging.hpp.em.watch"
   COMMENT "Expanding logging.hpp.em"
   VERBATIM
@@ -147,7 +149,7 @@ foreach(interface_file ${interface_files})
   string(REPLACE ";" "$<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_${interface_name}_traits}"
+    COMMAND Python3::Interpreter ARGS -c "${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
@@ -167,7 +169,7 @@ foreach(interface_file ${interface_files})
   string(REPLACE ";" "$<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_${interface_name}}"
+    COMMAND Python3::Interpreter ARGS -c "${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
@@ -185,13 +187,14 @@ endif()
 target_include_directories(${PROJECT_NAME} PUBLIC
   "$<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/include>"
   "$<BUILD_INTERFACE:${CMAKE_CURRENT_BINARY_DIR}/include>"
-  "$<INSTALL_INTERFACE:include>")
+  "$<INSTALL_INTERFACE:include/${PROJECT_NAME}>")
 target_link_libraries(${PROJECT_NAME} ${CMAKE_THREAD_LIBS_INIT})
 # specific order: dependents before dependencies
 ament_target_dependencies(${PROJECT_NAME}
   "ament_index_cpp"
   "libstatistics_collector"
   "rcl"
+  "rcl_interfaces"
   "rcl_yaml_param_parser"
   "rcpputils"
   "rcutils"
@@ -215,11 +218,14 @@ install(
   RUNTIME DESTINATION bin
 )
 
-# specific order: dependents before dependencies
-ament_export_include_directories(include)
+# Export old-style CMake variables
+ament_export_include_directories("include/${PROJECT_NAME}")
 ament_export_libraries(${PROJECT_NAME})
+
+# Export modern CMake targets
 ament_export_targets(${PROJECT_NAME})
 
+# specific order: dependents before dependencies
 ament_export_dependencies(ament_index_cpp)
 ament_export_dependencies(libstatistics_collector)
 ament_export_dependencies(rcl)
@@ -245,10 +251,12 @@ ament_package()
 
 install(
   DIRECTORY include/ ${CMAKE_CURRENT_BINARY_DIR}/include/
-  DESTINATION include
+  DESTINATION include/${PROJECT_NAME}
 )
 
 if(TEST cppcheck)
   # must set the property after ament_package()
   set_tests_properties(cppcheck PROPERTIES TIMEOUT 500)
 endif()
+
+ament_generate_version_header(${PROJECT_NAME})

rclcpp/Doxyfile

@@ -21,13 +21,22 @@ GENERATE_LATEX         = NO
 ENABLE_PREPROCESSING   = YES
 MACRO_EXPANSION        = YES
 EXPAND_ONLY_PREDEF     = YES
-PREDEFINED             = RCLCPP_PUBLIC=
+PREDEFINED             += DOXYGEN_ONLY
+PREDEFINED             += RCLCPP_LOCAL=
+PREDEFINED             += RCLCPP_PUBLIC=
+PREDEFINED             += RCLCPP_PUBLIC_TYPE=
+PREDEFINED             += RCUTILS_WARN_UNUSED=
+PREDEFINED             += RCPPUTILS_TSA_GUARDED_BY(x)=
+PREDEFINED             += RCPPUTILS_TSA_PT_GUARDED_BY(x)=
+PREDEFINED             += RCPPUTILS_TSA_REQUIRES(x)=
+
+DOT_GRAPH_MAX_NODES    = 101
 
 # Tag files that do not exist will produce a warning and cross-project linking will not work.
-TAGFILES += "../../../../doxygen_tag_files/cppreference-doxygen-web.tag.xml=http://en.cppreference.com/w/"
+#TAGFILES += "../../../../doxygen_tag_files/cppreference-doxygen-web.tag.xml=http://en.cppreference.com/w/"
 # Consider changing "latest" to the version you want to reference (e.g. beta1 or 1.0.0)
-TAGFILES += "../../../../doxygen_tag_files/rcl.tag=http://docs.ros2.org/latest/api/rcl/"
-TAGFILES += "../../../../doxygen_tag_files/rmw.tag=http://docs.ros2.org/latest/api/rmw/"
-TAGFILES += "../../../../doxygen_tag_files/rcutils.tag=http://docs.ros2.org/latest/api/rcutils/"
+#TAGFILES += "../../../../doxygen_tag_files/rcl.tag=http://docs.ros2.org/latest/api/rcl/"
+#TAGFILES += "../../../../doxygen_tag_files/rmw.tag=http://docs.ros2.org/latest/api/rmw/"
+#TAGFILES += "../../../../doxygen_tag_files/rcutils.tag=http://docs.ros2.org/latest/api/rcutils/"
 # Uncomment to generate tag files for cross-project linking.
 #GENERATE_TAGFILE = "../../../../doxygen_tag_files/rclcpp.tag"

rclcpp/QUALITY_DECLARATION.md

@@ -1,10 +1,10 @@
-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).
+This document is a declaration of software quality for the `rclcpp` package, based on the guidelines in [REP-2004](https://reps.openrobotics.org/rep-2004/).
 
 # 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.
+Below are the rationales, notes, and caveats for this claim, organized by each requirement listed in the [Package Quality Categories in REP-2004](https://reps.openrobotics.org/rep-2004/) of the ROS2 developer guide.
 
 ## Version Policy [1]
 
@@ -55,7 +55,7 @@ All pull requests will be peer-reviewed, check [ROS 2 Developer Guide](https://d
 
 ### 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)
+All pull requests must pass CI on all [tier 1 platforms](https://reps.openrobotics.org/rep-2000/#support-tiers)
 
 Currently nightly results can be seen here:
 
@@ -213,7 +213,7 @@ It is **Quality Level 1**, see its [Quality Declaration document](https://gitlab
 
 ## 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.
+`rclcpp` supports all of the tier 1 platforms as described in [REP-2000](https://reps.openrobotics.org/rep-2000/#support-tiers), and tests each change against all of them.
 
 Currently nightly build status can be seen here:
 * [linux-aarch64_release](https://ci.ros2.org/view/nightly/job/nightly_linux-aarch64_release/lastBuild/rclcpp/)
@@ -225,4 +225,4 @@ Currently nightly build status can be seen here:
 
 ### Vulnerability Disclosure Policy [7.i]
 
-This package conforms to the Vulnerability Disclosure Policy in [REP-2006](https://www.ros.org/reps/rep-2006.html).
+This package conforms to the Vulnerability Disclosure Policy in [REP-2006](https://reps.openrobotics.org/rep-2006/).

rclcpp/include/rclcpp/allocator/allocator_common.hpp

@@ -15,6 +15,7 @@
 #ifndef RCLCPP__ALLOCATOR__ALLOCATOR_COMMON_HPP_
 #define RCLCPP__ALLOCATOR__ALLOCATOR_COMMON_HPP_
 
+#include <cstring>
 #include <memory>
 
 #include "rcl/allocator.h"
@@ -39,6 +40,22 @@ void * retyped_allocate(size_t size, void * untyped_allocator)
   return std::allocator_traits<Alloc>::allocate(*typed_allocator, size);
 }
 
+template<typename Alloc>
+void * retyped_zero_allocate(size_t number_of_elem, size_t size_of_elem, void * untyped_allocator)
+{
+  auto typed_allocator = static_cast<Alloc *>(untyped_allocator);
+  if (!typed_allocator) {
+    throw std::runtime_error("Received incorrect allocator type");
+  }
+  size_t size = number_of_elem * size_of_elem;
+  void * allocated_memory =
+    std::allocator_traits<Alloc>::allocate(*typed_allocator, size);
+  if (allocated_memory) {
+    std::memset(allocated_memory, 0, size);
+  }
+  return allocated_memory;
+}
+
 template<typename T, typename Alloc>
 void retyped_deallocate(void * untyped_pointer, void * untyped_allocator)
 {
@@ -73,6 +90,7 @@ rcl_allocator_t get_rcl_allocator(Alloc & allocator)
   rcl_allocator_t rcl_allocator = rcl_get_default_allocator();
 #ifndef _WIN32
   rcl_allocator.allocate = &retyped_allocate<Alloc>;
+  rcl_allocator.zero_allocate = &retyped_zero_allocate<Alloc>;
   rcl_allocator.deallocate = &retyped_deallocate<T, Alloc>;
   rcl_allocator.reallocate = &retyped_reallocate<T, Alloc>;
   rcl_allocator.state = &allocator;

rclcpp/include/rclcpp/allocator/allocator_deleter.hpp

@@ -41,7 +41,7 @@ public:
   }
 
   template<typename T>
-  AllocatorDeleter(const AllocatorDeleter<T> & a)
+  explicit AllocatorDeleter(const AllocatorDeleter<T> & a)
   {
     allocator_ = a.get_allocator();
   }

rclcpp/include/rclcpp/any_service_callback.hpp

@@ -15,10 +15,12 @@
 #ifndef RCLCPP__ANY_SERVICE_CALLBACK_HPP_
 #define RCLCPP__ANY_SERVICE_CALLBACK_HPP_
 
+#include <variant>
 #include <functional>
 #include <memory>
 #include <stdexcept>
 #include <type_traits>
+#include <utility>
 
 #include "rclcpp/function_traits.hpp"
 #include "rclcpp/visibility_control.hpp"
@@ -29,93 +31,204 @@
 namespace rclcpp
 {
 
+namespace detail
+{
+template<typename T, typename = void>
+struct can_be_nullptr : std::false_type {};
+
+// Some lambdas define a comparison with nullptr,
+// but we see a warning that they can never be null when using it.
+// We also test if `T &` can be assigned to `nullptr` to avoid the issue.
+template<typename T>
+#ifdef __QNXNTO__
+struct can_be_nullptr<T, std::void_t<
+    decltype(std::declval<T>() == nullptr)>>: std::true_type {};
+#else
+struct can_be_nullptr<T, std::void_t<
+    decltype(std::declval<T>() == nullptr), decltype(std::declval<T &>() = nullptr)>>
+  : std::true_type {};
+#endif
+}  // namespace detail
+
+// Forward declare
+template<typename ServiceT>
+class Service;
+
 template<typename ServiceT>
 class AnyServiceCallback
 {
-private:
-  using SharedPtrCallback = std::function<
-    void (
-      const std::shared_ptr<typename ServiceT::Request>,
-      std::shared_ptr<typename ServiceT::Response>
-    )>;
-  using SharedPtrWithRequestHeaderCallback = std::function<
-    void (
-      const std::shared_ptr<rmw_request_id_t>,
-      const std::shared_ptr<typename ServiceT::Request>,
-      std::shared_ptr<typename ServiceT::Response>
-    )>;
-
-  SharedPtrCallback shared_ptr_callback_;
-  SharedPtrWithRequestHeaderCallback shared_ptr_with_request_header_callback_;
-
 public:
   AnyServiceCallback()
-  : shared_ptr_callback_(nullptr), shared_ptr_with_request_header_callback_(nullptr)
+  : callback_(std::monostate{})
   {}
 
-  AnyServiceCallback(const AnyServiceCallback &) = default;
-
   template<
     typename CallbackT,
-    typename std::enable_if<
+    typename std::enable_if_t<!detail::can_be_nullptr<CallbackT>::value, int> = 0>
+  void
+  set(CallbackT && callback)
+  {
+    // Workaround Windows issue with std::bind
+    if constexpr (
       rclcpp::function_traits::same_arguments<
         CallbackT,
         SharedPtrCallback
-      >::value
-    >::type * = nullptr
-  >
-  void set(CallbackT callback)
-  {
-    shared_ptr_callback_ = callback;
+      >::value)
+    {
+      callback_.template emplace<SharedPtrCallback>(callback);
+    } else if constexpr (  // NOLINT, can't satisfy both cpplint and uncrustify
+      rclcpp::function_traits::same_arguments<
+        CallbackT,
+        SharedPtrWithRequestHeaderCallback
+      >::value)
+    {
+      callback_.template emplace<SharedPtrWithRequestHeaderCallback>(callback);
+    } else if constexpr (  // NOLINT
+      rclcpp::function_traits::same_arguments<
+        CallbackT,
+        SharedPtrDeferResponseCallback
+      >::value)
+    {
+      callback_.template emplace<SharedPtrDeferResponseCallback>(callback);
+    } else if constexpr (  // NOLINT
+      rclcpp::function_traits::same_arguments<
+        CallbackT,
+        SharedPtrDeferResponseCallbackWithServiceHandle
+      >::value)
+    {
+      callback_.template emplace<SharedPtrDeferResponseCallbackWithServiceHandle>(callback);
+    } else {
+      // the else clause is not needed, but anyways we should only be doing this instead
+      // of all the above workaround ...
+      callback_ = std::forward<CallbackT>(callback);
+    }
   }
 
   template<
     typename CallbackT,
-    typename std::enable_if<
+    typename std::enable_if_t<detail::can_be_nullptr<CallbackT>::value, int> = 0>
+  void
+  set(CallbackT && callback)
+  {
+    if (!callback) {
+      throw std::invalid_argument("AnyServiceCallback::set(): callback cannot be nullptr");
+    }
+    // Workaround Windows issue with std::bind
+    if constexpr (
+      rclcpp::function_traits::same_arguments<
+        CallbackT,
+        SharedPtrCallback
+      >::value)
+    {
+      callback_.template emplace<SharedPtrCallback>(callback);
+    } else if constexpr (  // NOLINT
       rclcpp::function_traits::same_arguments<
         CallbackT,
         SharedPtrWithRequestHeaderCallback
-      >::value
-    >::type * = nullptr
-  >
-  void set(CallbackT callback)
-  {
-    shared_ptr_with_request_header_callback_ = callback;
+      >::value)
+    {
+      callback_.template emplace<SharedPtrWithRequestHeaderCallback>(callback);
+    } else if constexpr (  // NOLINT
+      rclcpp::function_traits::same_arguments<
+        CallbackT,
+        SharedPtrDeferResponseCallback
+      >::value)
+    {
+      callback_.template emplace<SharedPtrDeferResponseCallback>(callback);
+    } else if constexpr (  // NOLINT
+      rclcpp::function_traits::same_arguments<
+        CallbackT,
+        SharedPtrDeferResponseCallbackWithServiceHandle
+      >::value)
+    {
+      callback_.template emplace<SharedPtrDeferResponseCallbackWithServiceHandle>(callback);
+    } else {
+      // the else clause is not needed, but anyways we should only be doing this instead
+      // of all the above workaround ...
+      callback_ = std::forward<CallbackT>(callback);
+    }
   }
 
-  void dispatch(
-    std::shared_ptr<rmw_request_id_t> request_header,
-    std::shared_ptr<typename ServiceT::Request> request,
-    std::shared_ptr<typename ServiceT::Response> response)
+  // template<typename Allocator = std::allocator<typename ServiceT::Response>>
+  std::shared_ptr<typename ServiceT::Response>
+  dispatch(
+    const std::shared_ptr<rclcpp::Service<ServiceT>> & service_handle,
+    const std::shared_ptr<rmw_request_id_t> & request_header,
+    std::shared_ptr<typename ServiceT::Request> request)
   {
     TRACEPOINT(callback_start, static_cast<const void *>(this), false);
-    if (shared_ptr_callback_ != nullptr) {
+    if (std::holds_alternative<std::monostate>(callback_)) {
+      // TODO(ivanpauno): Remove the set method, and force the users of this class
+      // to pass a callback at construnciton.
+      throw std::runtime_error{"unexpected request without any callback set"};
+    }
+    if (std::holds_alternative<SharedPtrDeferResponseCallback>(callback_)) {
+      const auto & cb = std::get<SharedPtrDeferResponseCallback>(callback_);
+      cb(request_header, std::move(request));
+      return nullptr;
+    }
+    if (std::holds_alternative<SharedPtrDeferResponseCallbackWithServiceHandle>(callback_)) {
+      const auto & cb = std::get<SharedPtrDeferResponseCallbackWithServiceHandle>(callback_);
+      cb(service_handle, request_header, std::move(request));
+      return nullptr;
+    }
+    // auto response = allocate_shared<typename ServiceT::Response, Allocator>();
+    auto response = std::make_shared<typename ServiceT::Response>();
+    if (std::holds_alternative<SharedPtrCallback>(callback_)) {
       (void)request_header;
-      shared_ptr_callback_(request, response);
-    } else if (shared_ptr_with_request_header_callback_ != nullptr) {
-      shared_ptr_with_request_header_callback_(request_header, request, response);
-    } else {
-      throw std::runtime_error("unexpected request without any callback set");
+      const auto & cb = std::get<SharedPtrCallback>(callback_);
+      cb(std::move(request), response);
+    } else if (std::holds_alternative<SharedPtrWithRequestHeaderCallback>(callback_)) {
+      const auto & cb = std::get<SharedPtrWithRequestHeaderCallback>(callback_);
+      cb(request_header, std::move(request), response);
     }
     TRACEPOINT(callback_end, static_cast<const void *>(this));
+    return response;
   }
 
   void register_callback_for_tracing()
   {
 #ifndef TRACETOOLS_DISABLED
-    if (shared_ptr_callback_) {
-      TRACEPOINT(
-        rclcpp_callback_register,
-        static_cast<const void *>(this),
-        tracetools::get_symbol(shared_ptr_callback_));
-    } else if (shared_ptr_with_request_header_callback_) {
-      TRACEPOINT(
-        rclcpp_callback_register,
-        static_cast<const void *>(this),
-        tracetools::get_symbol(shared_ptr_with_request_header_callback_));
-    }
+    std::visit(
+      [this](auto && arg) {
+        TRACEPOINT(
+          rclcpp_callback_register,
+          static_cast<const void *>(this),
+          tracetools::get_symbol(arg));
+      }, callback_);
 #endif  // TRACETOOLS_DISABLED
   }
+
+private:
+  using SharedPtrCallback = std::function<
+    void (
+      std::shared_ptr<typename ServiceT::Request>,
+      std::shared_ptr<typename ServiceT::Response>
+    )>;
+  using SharedPtrWithRequestHeaderCallback = std::function<
+    void (
+      std::shared_ptr<rmw_request_id_t>,
+      std::shared_ptr<typename ServiceT::Request>,
+      std::shared_ptr<typename ServiceT::Response>
+    )>;
+  using SharedPtrDeferResponseCallback = std::function<
+    void (
+      std::shared_ptr<rmw_request_id_t>,
+      std::shared_ptr<typename ServiceT::Request>
+    )>;
+  using SharedPtrDeferResponseCallbackWithServiceHandle = std::function<
+    void (
+      std::shared_ptr<rclcpp::Service<ServiceT>>,
+      std::shared_ptr<rmw_request_id_t>,
+      std::shared_ptr<typename ServiceT::Request>
+    )>;
+
+  std::variant<
+    std::monostate,
+    SharedPtrCallback,
+    SharedPtrWithRequestHeaderCallback,
+    SharedPtrDeferResponseCallback,
+    SharedPtrDeferResponseCallbackWithServiceHandle> callback_;
 };
 
 }  // namespace rclcpp

rclcpp/include/rclcpp/any_subscription_callback.hpp

@@ -354,12 +354,6 @@ public:
     allocator::set_allocator_for_deleter(&ros_message_type_deleter_, &ros_message_type_allocator_);
   }
 
-  [[deprecated("use AnySubscriptionCallback(const AllocatorT & allocator) instead")]]
-  explicit
-  AnySubscriptionCallback(std::shared_ptr<AllocatorT> allocator)  // NOLINT[runtime/explicit]
-  : AnySubscriptionCallback(*NotNull<AllocatorT>(allocator.get(), "invalid allocator").pointer)
-  {}
-
   AnySubscriptionCallback(const AnySubscriptionCallback &) = default;
 
   /// Generic function for setting the callback.
@@ -406,10 +400,10 @@ public:
 
   /// Function for shared_ptr to non-const MessageT, which is deprecated.
   template<typename SetT>
-  // TODO(wjwwood): enable this deprecation after Galactic
-  // [[deprecated(
-  //   "use 'void (std::shared_ptr<const MessageT>)' instead"
-  // )]]
+#if !defined(RCLCPP_AVOID_DEPRECATIONS_FOR_UNIT_TESTS)
+  // suppress deprecation warnings in `test_any_subscription_callback.cpp`
+  [[deprecated("use 'void(std::shared_ptr<const MessageT>)' instead")]]
+#endif
   void
   set_deprecated(std::function<void(std::shared_ptr<SetT>)> callback)
   {
@@ -418,10 +412,12 @@ public:
 
   /// Function for shared_ptr to non-const MessageT with MessageInfo, which is deprecated.
   template<typename SetT>
-  // TODO(wjwwood): enable this deprecation after Galactic
-  // [[deprecated(
-  //   "use 'void (std::shared_ptr<const MessageT>, const rclcpp::MessageInfo &)' instead"
-  // )]]
+#if !defined(RCLCPP_AVOID_DEPRECATIONS_FOR_UNIT_TESTS)
+  // suppress deprecation warnings in `test_any_subscription_callback.cpp`
+  [[deprecated(
+          "use 'void(std::shared_ptr<const MessageT>, const rclcpp::MessageInfo &)' instead"
+  )]]
+#endif
   void
   set_deprecated(std::function<void(std::shared_ptr<SetT>, const rclcpp::MessageInfo &)> callback)
   {
@@ -474,6 +470,22 @@ public:
     }
   }
 
+  std::unique_ptr<ROSMessageType, ROSMessageTypeDeleter>
+  convert_custom_type_to_ros_message_unique_ptr(const SubscribedType & msg)
+  {
+    if constexpr (rclcpp::TypeAdapter<MessageT>::is_specialized::value) {
+      auto ptr = ROSMessageTypeAllocatorTraits::allocate(ros_message_type_allocator_, 1);
+      ROSMessageTypeAllocatorTraits::construct(ros_message_type_allocator_, ptr);
+      rclcpp::TypeAdapter<MessageT>::convert_to_ros_message(msg, *ptr);
+      return std::unique_ptr<ROSMessageType, ROSMessageTypeDeleter>(ptr, ros_message_type_deleter_);
+    } else {
+      static_assert(
+        !sizeof(MessageT *),
+        "convert_custom_type_to_ros_message_unique_ptr() "
+        "unexpectedly called without specialized TypeAdapter");
+    }
+  }
+
   // Dispatch when input is a ros message and the output could be anything.
   void
   dispatch(
@@ -656,7 +668,7 @@ public:
 
   void
   dispatch_intra_process(
-    std::shared_ptr<const ROSMessageType> message,
+    std::shared_ptr<const SubscribedType> message,
     const rclcpp::MessageInfo & message_info)
   {
     TRACEPOINT(callback_start, static_cast<const void *>(this), true);
@@ -675,65 +687,89 @@ public:
 
         // conditions for custom type
         if constexpr (is_ta && std::is_same_v<T, ConstRefCallback>) {
-          auto local_message = convert_ros_message_to_custom_type_unique_ptr(*message);
-          callback(*local_message);
+          callback(*message);
         } else if constexpr (is_ta && std::is_same_v<T, ConstRefWithInfoCallback>) {  // NOLINT
-          auto local_message = convert_ros_message_to_custom_type_unique_ptr(*message);
-          callback(*local_message, message_info);
+          callback(*message, message_info);
         } else if constexpr (  // NOLINT[readability/braces]
           is_ta && (
             std::is_same_v<T, UniquePtrCallback>||
             std::is_same_v<T, SharedPtrCallback>
         ))
         {
-          callback(convert_ros_message_to_custom_type_unique_ptr(*message));
+          callback(create_custom_unique_ptr_from_custom_shared_ptr_message(message));
         } else if constexpr (  // NOLINT[readability/braces]
           is_ta && (
             std::is_same_v<T, UniquePtrWithInfoCallback>||
             std::is_same_v<T, SharedPtrWithInfoCallback>
         ))
         {
-          callback(convert_ros_message_to_custom_type_unique_ptr(*message), message_info);
+          callback(create_custom_unique_ptr_from_custom_shared_ptr_message(message), message_info);
         } else if constexpr (  // NOLINT[readability/braces]
           is_ta && (
             std::is_same_v<T, SharedConstPtrCallback>||
             std::is_same_v<T, ConstRefSharedConstPtrCallback>
         ))
         {
-          callback(convert_ros_message_to_custom_type_unique_ptr(*message));
+          callback(message);
         } else if constexpr (  // NOLINT[readability/braces]
           is_ta && (
             std::is_same_v<T, SharedConstPtrWithInfoCallback>||
             std::is_same_v<T, ConstRefSharedConstPtrWithInfoCallback>
         ))
         {
-          callback(convert_ros_message_to_custom_type_unique_ptr(*message), message_info);
+          callback(message, message_info);
         }
         // conditions for ros message type
-        else if constexpr (std::is_same_v<T, ConstRefROSMessageCallback>) {  // NOLINT
-          callback(*message);
-        } else if constexpr (std::is_same_v<T, ConstRefWithInfoROSMessageCallback>) {
-          callback(*message, message_info);
+        else if constexpr (std::is_same_v<T, ConstRefROSMessageCallback>) {  // NOLINT[readability/braces]
+          if constexpr (is_ta) {
+            auto local = convert_custom_type_to_ros_message_unique_ptr(*message);
+            callback(*local);
+          } else {
+            callback(*message);
+          }
+        } else if constexpr (std::is_same_v<T, ConstRefWithInfoROSMessageCallback>) {  // NOLINT[readability/braces]
+          if constexpr (is_ta) {
+            auto local = convert_custom_type_to_ros_message_unique_ptr(*message);
+            callback(*local, message_info);
+          } else {
+            callback(*message, message_info);
+          }
         } else if constexpr (  // NOLINT[readability/braces]
           std::is_same_v<T, UniquePtrROSMessageCallback>||
           std::is_same_v<T, SharedPtrROSMessageCallback>)
         {
-          callback(create_ros_unique_ptr_from_ros_shared_ptr_message(message));
+          if constexpr (is_ta) {
+            callback(convert_custom_type_to_ros_message_unique_ptr(*message));
+          } else {
+            callback(create_ros_unique_ptr_from_ros_shared_ptr_message(message));
+          }
         } else if constexpr (  // NOLINT[readability/braces]
           std::is_same_v<T, UniquePtrWithInfoROSMessageCallback>||
           std::is_same_v<T, SharedPtrWithInfoROSMessageCallback>)
         {
-          callback(create_ros_unique_ptr_from_ros_shared_ptr_message(message), message_info);
+          if constexpr (is_ta) {
+            callback(convert_custom_type_to_ros_message_unique_ptr(*message), message_info);
+          } else {
+            callback(create_ros_unique_ptr_from_ros_shared_ptr_message(message), message_info);
+          }
         } else if constexpr (  // NOLINT[readability/braces]
           std::is_same_v<T, SharedConstPtrROSMessageCallback>||
           std::is_same_v<T, ConstRefSharedConstPtrROSMessageCallback>)
         {
-          callback(message);
+          if constexpr (is_ta) {
+            callback(convert_custom_type_to_ros_message_unique_ptr(*message));
+          } else {
+            callback(message);
+          }
         } else if constexpr (  // NOLINT[readability/braces]
           std::is_same_v<T, SharedConstPtrWithInfoROSMessageCallback>||
           std::is_same_v<T, ConstRefSharedConstPtrWithInfoROSMessageCallback>)
         {
-          callback(message, message_info);
+          if constexpr (is_ta) {
+            callback(convert_custom_type_to_ros_message_unique_ptr(*message), message_info);
+          } else {
+            callback(message, message_info);
+          }
         }
         // condition to catch SerializedMessage types
         else if constexpr (  // NOLINT[readability/braces]
@@ -762,7 +798,7 @@ public:
 
   void
   dispatch_intra_process(
-    std::unique_ptr<ROSMessageType, ROSMessageTypeDeleter> message,
+    std::unique_ptr<SubscribedType, SubscribedTypeDeleter> message,
     const rclcpp::MessageInfo & message_info)
   {
     TRACEPOINT(callback_start, static_cast<const void *>(this), true);
@@ -776,70 +812,98 @@ public:
     // Dispatch.
     std::visit(
       [&message, &message_info, this](auto && callback) {
+        // clang complains that 'this' lambda capture is unused, which is true
+        // in *some* specializations of this template, but not others.  Just
+        // quiet it down.
+        (void)this;
+
         using T = std::decay_t<decltype(callback)>;
         static constexpr bool is_ta = rclcpp::TypeAdapter<MessageT>::is_specialized::value;
 
         // conditions for custom type
         if constexpr (is_ta && std::is_same_v<T, ConstRefCallback>) {
-          auto local_message = convert_ros_message_to_custom_type_unique_ptr(*message);
-          callback(*local_message);
+          callback(*message);
         } else if constexpr (is_ta && std::is_same_v<T, ConstRefWithInfoCallback>) {  // NOLINT
-          auto local_message = convert_ros_message_to_custom_type_unique_ptr(*message);
-          callback(*local_message, message_info);
+          callback(*message, message_info);
         } else if constexpr (  // NOLINT[readability/braces]
           is_ta && (
             std::is_same_v<T, UniquePtrCallback>||
-            std::is_same_v<T, SharedPtrCallback>
-        ))
+            std::is_same_v<T, SharedPtrCallback>))
         {
-          callback(convert_ros_message_to_custom_type_unique_ptr(*message));
+          callback(std::move(message));
         } else if constexpr (  // NOLINT[readability/braces]
           is_ta && (
             std::is_same_v<T, UniquePtrWithInfoCallback>||
             std::is_same_v<T, SharedPtrWithInfoCallback>
         ))
         {
-          callback(convert_ros_message_to_custom_type_unique_ptr(*message), message_info);
+          callback(std::move(message), message_info);
         } else if constexpr (  // NOLINT[readability/braces]
           is_ta && (
             std::is_same_v<T, SharedConstPtrCallback>||
             std::is_same_v<T, ConstRefSharedConstPtrCallback>
         ))
         {
-          callback(convert_ros_message_to_custom_type_unique_ptr(*message));
+          callback(std::move(message));
         } else if constexpr (  // NOLINT[readability/braces]
           is_ta && (
             std::is_same_v<T, SharedConstPtrWithInfoCallback>||
             std::is_same_v<T, ConstRefSharedConstPtrWithInfoCallback>
         ))
         {
-          callback(convert_ros_message_to_custom_type_unique_ptr(*message), message_info);
+          callback(std::move(message), message_info);
         }
         // conditions for ros message type
-        else if constexpr (std::is_same_v<T, ConstRefROSMessageCallback>) {  // NOLINT
-          callback(*message);
-        } else if constexpr (std::is_same_v<T, ConstRefWithInfoROSMessageCallback>) {
-          callback(*message, message_info);
+        else if constexpr (std::is_same_v<T, ConstRefROSMessageCallback>) {  // NOLINT[readability/braces]
+          if constexpr (is_ta) {
+            auto local = convert_custom_type_to_ros_message_unique_ptr(*message);
+            callback(*local);
+          } else {
+            callback(*message);
+          }
+        } else if constexpr (std::is_same_v<T, ConstRefWithInfoROSMessageCallback>) {  // NOLINT[readability/braces]
+          if constexpr (is_ta) {
+            auto local = convert_custom_type_to_ros_message_unique_ptr(*message);
+            callback(*local, message_info);
+          } else {
+            callback(*message, message_info);
+          }
         } else if constexpr (  // NOLINT[readability/braces]
           std::is_same_v<T, UniquePtrROSMessageCallback>||
           std::is_same_v<T, SharedPtrROSMessageCallback>)
         {
-          callback(std::move(message));
+          if constexpr (is_ta) {
+            callback(convert_custom_type_to_ros_message_unique_ptr(*message));
+          } else {
+            callback(std::move(message));
+          }
         } else if constexpr (  // NOLINT[readability/braces]
           std::is_same_v<T, UniquePtrWithInfoROSMessageCallback>||
           std::is_same_v<T, SharedPtrWithInfoROSMessageCallback>)
         {
-          callback(std::move(message), message_info);
+          if constexpr (is_ta) {
+            callback(convert_custom_type_to_ros_message_unique_ptr(*message), message_info);
+          } else {
+            callback(std::move(message), message_info);
+          }
         } else if constexpr (  // NOLINT[readability/braces]
           std::is_same_v<T, SharedConstPtrROSMessageCallback>||
           std::is_same_v<T, ConstRefSharedConstPtrROSMessageCallback>)
         {
-          callback(std::move(message));
+          if constexpr (is_ta) {
+            callback(convert_custom_type_to_ros_message_unique_ptr(*message));
+          } else {
+            callback(std::move(message));
+          }
         } else if constexpr (  // NOLINT[readability/braces]
           std::is_same_v<T, SharedConstPtrWithInfoROSMessageCallback>||
           std::is_same_v<T, ConstRefSharedConstPtrWithInfoROSMessageCallback>)
         {
-          callback(std::move(message), message_info);
+          if constexpr (is_ta) {
+            callback(convert_custom_type_to_ros_message_unique_ptr(*message), message_info);
+          } else {
+            callback(std::move(message), message_info);
+          }
         }
         // condition to catch SerializedMessage types
         else if constexpr (  // NOLINT[readability/braces]
@@ -886,7 +950,13 @@ public:
       std::holds_alternative<UniquePtrSerializedMessageCallback>(callback_variant_) ||
       std::holds_alternative<SharedConstPtrSerializedMessageCallback>(callback_variant_) ||
       std::holds_alternative<ConstRefSharedConstPtrSerializedMessageCallback>(callback_variant_) ||
-      std::holds_alternative<SharedPtrSerializedMessageCallback>(callback_variant_);
+      std::holds_alternative<SharedPtrSerializedMessageCallback>(callback_variant_) ||
+      std::holds_alternative<ConstRefSerializedMessageWithInfoCallback>(callback_variant_) ||
+      std::holds_alternative<UniquePtrSerializedMessageWithInfoCallback>(callback_variant_) ||
+      std::holds_alternative<SharedConstPtrSerializedMessageWithInfoCallback>(callback_variant_) ||
+      std::holds_alternative<ConstRefSharedConstPtrSerializedMessageWithInfoCallback>(
+      callback_variant_) ||
+      std::holds_alternative<SharedPtrSerializedMessageWithInfoCallback>(callback_variant_);
   }
 
   void

rclcpp/include/rclcpp/callback_group.hpp

@@ -16,11 +16,14 @@
 #define RCLCPP__CALLBACK_GROUP_HPP_
 
 #include <atomic>
+#include <functional>
+#include <memory>
 #include <mutex>
-#include <string>
 #include <vector>
 
 #include "rclcpp/client.hpp"
+#include "rclcpp/context.hpp"
+#include "rclcpp/guard_condition.hpp"
 #include "rclcpp/publisher_base.hpp"
 #include "rclcpp/service.hpp"
 #include "rclcpp/subscription_base.hpp"
@@ -95,6 +98,10 @@ public:
     CallbackGroupType group_type,
     bool automatically_add_to_executor_with_node = true);
 
+  /// Default destructor.
+  RCLCPP_PUBLIC
+  ~CallbackGroup();
+
   template<typename Function>
   rclcpp::SubscriptionBase::SharedPtr
   find_subscription_ptrs_if(Function func) const
@@ -138,6 +145,14 @@ public:
   const CallbackGroupType &
   type() const;
 
+  RCLCPP_PUBLIC
+  void collect_all_ptrs(
+    std::function<void(const rclcpp::SubscriptionBase::SharedPtr &)> sub_func,
+    std::function<void(const rclcpp::ServiceBase::SharedPtr &)> service_func,
+    std::function<void(const rclcpp::ClientBase::SharedPtr &)> client_func,
+    std::function<void(const rclcpp::TimerBase::SharedPtr &)> timer_func,
+    std::function<void(const rclcpp::Waitable::SharedPtr &)> waitable_func) const;
+
   /// Return a reference to the 'associated with executor' atomic boolean.
   /**
    * When a callback group is added to an executor this boolean is checked
@@ -163,6 +178,16 @@ public:
   bool
   automatically_add_to_executor_with_node() const;
 
+  /// Defer creating the notify guard condition and return it.
+  RCLCPP_PUBLIC
+  rclcpp::GuardCondition::SharedPtr
+  get_notify_guard_condition(const rclcpp::Context::SharedPtr context_ptr);
+
+  /// Trigger the notify guard condition.
+  RCLCPP_PUBLIC
+  void
+  trigger_notify_guard_condition();
+
 protected:
   RCLCPP_DISABLE_COPY(CallbackGroup)
 
@@ -205,6 +230,9 @@ protected:
   std::vector<rclcpp::Waitable::WeakPtr> waitable_ptrs_;
   std::atomic_bool can_be_taken_from_;
   const bool automatically_add_to_executor_with_node_;
+  // defer the creation of the guard condition
+  std::shared_ptr<rclcpp::GuardCondition> notify_guard_condition_ = nullptr;
+  std::recursive_mutex notify_guard_condition_mutex_;
 
 private:
   template<typename TypeT, typename Function>

rclcpp/include/rclcpp/client.hpp

@@ -17,34 +17,103 @@
 
 #include <atomic>
 #include <future>
-#include <map>
+#include <unordered_map>
 #include <memory>
+#include <mutex>
+#include <optional>  // NOLINT, cpplint doesn't think this is a cpp std header
 #include <sstream>
 #include <string>
 #include <tuple>
 #include <utility>
+#include <variant>  // NOLINT
+#include <vector>
 
 #include "rcl/client.h"
 #include "rcl/error_handling.h"
+#include "rcl/event_callback.h"
 #include "rcl/wait.h"
 
+#include "rclcpp/detail/cpp_callback_trampoline.hpp"
 #include "rclcpp/exceptions.hpp"
+#include "rclcpp/expand_topic_or_service_name.hpp"
 #include "rclcpp/function_traits.hpp"
+#include "rclcpp/logging.hpp"
 #include "rclcpp/macros.hpp"
 #include "rclcpp/node_interfaces/node_graph_interface.hpp"
+#include "rclcpp/qos.hpp"
 #include "rclcpp/type_support_decl.hpp"
 #include "rclcpp/utilities.hpp"
-#include "rclcpp/expand_topic_or_service_name.hpp"
 #include "rclcpp/visibility_control.hpp"
 
-#include "rcutils/logging_macros.h"
-
 #include "rmw/error_handling.h"
+#include "rmw/impl/cpp/demangle.hpp"
 #include "rmw/rmw.h"
 
 namespace rclcpp
 {
 
+namespace detail
+{
+template<typename FutureT>
+struct FutureAndRequestId
+{
+  FutureT future;
+  int64_t request_id;
+
+  FutureAndRequestId(FutureT impl, int64_t req_id)
+  : future(std::move(impl)), request_id(req_id)
+  {}
+
+  /// Allow implicit conversions to `std::future` by reference.
+  operator FutureT &() {return this->future;}
+
+  /// Deprecated, use the `future` member variable instead.
+  /**
+   * Allow implicit conversions to `std::future` by value.
+   * \deprecated
+   */
+  [[deprecated("FutureAndRequestId: use .future instead of an implicit conversion")]]
+  operator FutureT() {return this->future;}
+
+  // delegate future like methods in the std::future impl_
+
+  /// See std::future::get().
+  auto get() {return this->future.get();}
+  /// See std::future::valid().
+  bool valid() const noexcept {return this->future.valid();}
+  /// See std::future::wait().
+  void wait() const {return this->future.wait();}
+  /// See std::future::wait_for().
+  template<class Rep, class Period>
+  std::future_status wait_for(
+    const std::chrono::duration<Rep, Period> & timeout_duration) const
+  {
+    return this->future.wait_for(timeout_duration);
+  }
+  /// See std::future::wait_until().
+  template<class Clock, class Duration>
+  std::future_status wait_until(
+    const std::chrono::time_point<Clock, Duration> & timeout_time) const
+  {
+    return this->future.wait_until(timeout_time);
+  }
+
+  // Rule of five, we could use the rule of zero here, but better be explicit as some of the
+  // methods are deleted.
+
+  /// Move constructor.
+  FutureAndRequestId(FutureAndRequestId && other) noexcept = default;
+  /// Deleted copy constructor, each instance is a unique owner of the future.
+  FutureAndRequestId(const FutureAndRequestId & other) = delete;
+  /// Move assignment.
+  FutureAndRequestId & operator=(FutureAndRequestId && other) noexcept = default;
+  /// Deleted copy assignment, each instance is a unique owner of the future.
+  FutureAndRequestId & operator=(const FutureAndRequestId & other) = delete;
+  /// Destructor.
+  ~FutureAndRequestId() = default;
+};
+}  // namespace detail
+
 namespace node_interfaces
 {
 class NodeBaseInterface;
@@ -150,6 +219,122 @@ public:
   bool
   exchange_in_use_by_wait_set_state(bool in_use_state);
 
+  /// Get the actual request publsher QoS settings, after the defaults have been determined.
+  /**
+   * The actual configuration applied when using RMW_QOS_POLICY_*_SYSTEM_DEFAULT
+   * can only be resolved after the creation of the client, and it
+   * depends on the underlying rmw implementation.
+   * If the underlying setting in use can't be represented in ROS terms,
+   * it will be set to RMW_QOS_POLICY_*_UNKNOWN.
+   * May throw runtime_error when an unexpected error occurs.
+   *
+   * \return The actual request publsher qos settings.
+   * \throws std::runtime_error if failed to get qos settings
+   */
+  RCLCPP_PUBLIC
+  rclcpp::QoS
+  get_request_publisher_actual_qos() const;
+
+  /// Get the actual response subscription QoS settings, after the defaults have been determined.
+  /**
+   * The actual configuration applied when using RMW_QOS_POLICY_*_SYSTEM_DEFAULT
+   * can only be resolved after the creation of the client, and it
+   * depends on the underlying rmw implementation.
+   * If the underlying setting in use can't be represented in ROS terms,
+   * it will be set to RMW_QOS_POLICY_*_UNKNOWN.
+   * May throw runtime_error when an unexpected error occurs.
+   *
+   * \return The actual response subscription qos settings.
+   * \throws std::runtime_error if failed to get qos settings
+   */
+  RCLCPP_PUBLIC
+  rclcpp::QoS
+  get_response_subscription_actual_qos() const;
+
+  /// Set a callback to be called when each new response is received.
+  /**
+   * The callback receives a size_t which is the number of responses received
+   * since the last time this callback was called.
+   * Normally this is 1, but can be > 1 if responses were received before any
+   * callback was set.
+   *
+   * Since this callback is called from the middleware, you should aim to make
+   * it fast and not blocking.
+   * If you need to do a lot of work or wait for some other event, you should
+   * spin it off to another thread, otherwise you risk blocking the middleware.
+   *
+   * Calling it again will clear any previously set callback.
+   *
+   * An exception will be thrown if the callback is not callable.
+   *
+   * This function is thread-safe.
+   *
+   * If you want more information available in the callback, like the client
+   * or other information, you may use a lambda with captures or std::bind.
+   *
+   * \sa rmw_client_set_on_new_response_callback
+   * \sa rcl_client_set_on_new_response_callback
+   *
+   * \param[in] callback functor to be called when a new response is received
+   */
+  void
+  set_on_new_response_callback(std::function<void(size_t)> callback)
+  {
+    if (!callback) {
+      throw std::invalid_argument(
+              "The callback passed to set_on_new_response_callback "
+              "is not callable.");
+    }
+
+    auto new_callback =
+      [callback, this](size_t number_of_responses) {
+        try {
+          callback(number_of_responses);
+        } catch (const std::exception & exception) {
+          RCLCPP_ERROR_STREAM(
+            node_logger_,
+            "rclcpp::ClientBase@" << this <<
+              " caught " << rmw::impl::cpp::demangle(exception) <<
+              " exception in user-provided callback for the 'on new response' callback: " <<
+              exception.what());
+        } catch (...) {
+          RCLCPP_ERROR_STREAM(
+            node_logger_,
+            "rclcpp::ClientBase@" << this <<
+              " caught unhandled exception in user-provided callback " <<
+              "for the 'on new response' callback");
+        }
+      };
+
+    std::lock_guard<std::recursive_mutex> lock(callback_mutex_);
+
+    // Set it temporarily to the new callback, while we replace the old one.
+    // This two-step setting, prevents a gap where the old std::function has
+    // been replaced but the middleware hasn't been told about the new one yet.
+    set_on_new_response_callback(
+      rclcpp::detail::cpp_callback_trampoline<const void *, size_t>,
+      static_cast<const void *>(&new_callback));
+
+    // Store the std::function to keep it in scope, also overwrites the existing one.
+    on_new_response_callback_ = new_callback;
+
+    // Set it again, now using the permanent storage.
+    set_on_new_response_callback(
+      rclcpp::detail::cpp_callback_trampoline<const void *, size_t>,
+      static_cast<const void *>(&on_new_response_callback_));
+  }
+
+  /// Unset the callback registered for new responses, if any.
+  void
+  clear_on_new_response_callback()
+  {
+    std::lock_guard<std::recursive_mutex> lock(callback_mutex_);
+    if (on_new_response_callback_) {
+      set_on_new_response_callback(nullptr, nullptr);
+      on_new_response_callback_ = nullptr;
+    }
+  }
+
 protected:
   RCLCPP_DISABLE_COPY(ClientBase)
 
@@ -165,19 +350,30 @@ protected:
   const rcl_node_t *
   get_rcl_node_handle() const;
 
+  RCLCPP_PUBLIC
+  void
+  set_on_new_response_callback(rcl_event_callback_t callback, const void * user_data);
+
   rclcpp::node_interfaces::NodeGraphInterface::WeakPtr node_graph_;
   std::shared_ptr<rcl_node_t> node_handle_;
   std::shared_ptr<rclcpp::Context> context_;
+  rclcpp::Logger node_logger_;
 
   std::shared_ptr<rcl_client_t> client_handle_;
 
   std::atomic<bool> in_use_by_wait_set_{false};
+
+  std::recursive_mutex callback_mutex_;
+  std::function<void(size_t)> on_new_response_callback_{nullptr};
 };
 
 template<typename ServiceT>
 class Client : public ClientBase
 {
 public:
+  using Request = typename ServiceT::Request;
+  using Response = typename ServiceT::Response;
+
   using SharedRequest = typename ServiceT::Request::SharedPtr;
   using SharedResponse = typename ServiceT::Response::SharedPtr;
 
@@ -187,6 +383,7 @@ public:
   using SharedPromise = std::shared_ptr<Promise>;
   using SharedPromiseWithRequest = std::shared_ptr<PromiseWithRequest>;
 
+  using Future = std::future<SharedResponse>;
   using SharedFuture = std::shared_future<SharedResponse>;
   using SharedFutureWithRequest = std::shared_future<std::pair<SharedRequest, SharedResponse>>;
 
@@ -195,6 +392,64 @@ public:
 
   RCLCPP_SMART_PTR_DEFINITIONS(Client)
 
+  /// A convenient Client::Future and request id pair.
+  /**
+   * Public members:
+   * - future: a std::future<SharedResponse>.
+   * - request_id: the request id associated with the future.
+   *
+   * All the other methods are equivalent to the ones std::future provides.
+   */
+  struct FutureAndRequestId
+    : detail::FutureAndRequestId<std::future<SharedResponse>>
+  {
+    using detail::FutureAndRequestId<std::future<SharedResponse>>::FutureAndRequestId;
+
+    /// Deprecated, use `.future.share()` instead.
+    /**
+     * Allow implicit conversions to `std::shared_future` by value.
+     * \deprecated
+     */
+    [[deprecated(
+      "FutureAndRequestId: use .future.share() instead of an implicit conversion")]]
+    operator SharedFuture() {return this->future.share();}
+
+    // delegate future like methods in the std::future impl_
+
+    /// See std::future::share().
+    SharedFuture share() noexcept {return this->future.share();}
+  };
+
+  /// A convenient Client::SharedFuture and request id pair.
+  /**
+   * Public members:
+   * - future: a std::shared_future<SharedResponse>.
+   * - request_id: the request id associated with the future.
+   *
+   * All the other methods are equivalent to the ones std::shared_future provides.
+   */
+  struct SharedFutureAndRequestId
+    : detail::FutureAndRequestId<std::shared_future<SharedResponse>>
+  {
+    using detail::FutureAndRequestId<std::shared_future<SharedResponse>>::FutureAndRequestId;
+  };
+
+  /// A convenient Client::SharedFutureWithRequest and request id pair.
+  /**
+   * Public members:
+   * - future: a std::shared_future<SharedResponse>.
+   * - request_id: the request id associated with the future.
+   *
+   * All the other methods are equivalent to the ones std::shared_future provides.
+   */
+  struct SharedFutureWithRequestAndRequestId
+    : detail::FutureAndRequestId<std::shared_future<std::pair<SharedRequest, SharedResponse>>>
+  {
+    using detail::FutureAndRequestId<
+      std::shared_future<std::pair<SharedRequest, SharedResponse>>
+    >::FutureAndRequestId;
+  };
+
   /// Default constructor.
   /**
    * The constructor for a Client is almost never called directly.
@@ -292,34 +547,89 @@ public:
     std::shared_ptr<rmw_request_id_t> request_header,
     std::shared_ptr<void> response) override
   {
-    std::unique_lock<std::mutex> lock(pending_requests_mutex_);
-    auto typed_response = std::static_pointer_cast<typename ServiceT::Response>(response);
-    int64_t sequence_number = request_header->sequence_number;
-    // TODO(esteve) this should throw instead since it is not expected to happen in the first place
-    if (this->pending_requests_.count(sequence_number) == 0) {
-      RCUTILS_LOG_ERROR_NAMED(
-        "rclcpp",
-        "Received invalid sequence number. Ignoring...");
+    std::optional<CallbackInfoVariant>
+    optional_pending_request = this->get_and_erase_pending_request(request_header->sequence_number);
+    if (!optional_pending_request) {
       return;
     }
-    auto tuple = this->pending_requests_[sequence_number];
-    auto call_promise = std::get<0>(tuple);
-    auto callback = std::get<1>(tuple);
-    auto future = std::get<2>(tuple);
-    this->pending_requests_.erase(sequence_number);
-    // Unlock here to allow the service to be called recursively from one of its callbacks.
-    lock.unlock();
-
-    call_promise->set_value(typed_response);
-    callback(future);
+    auto & value = *optional_pending_request;
+    auto typed_response = std::static_pointer_cast<typename ServiceT::Response>(
+      std::move(response));
+    if (std::holds_alternative<Promise>(value)) {
+      auto & promise = std::get<Promise>(value);
+      promise.set_value(std::move(typed_response));
+    } else if (std::holds_alternative<CallbackTypeValueVariant>(value)) {
+      auto & inner = std::get<CallbackTypeValueVariant>(value);
+      const auto & callback = std::get<CallbackType>(inner);
+      auto & promise = std::get<Promise>(inner);
+      auto & future = std::get<SharedFuture>(inner);
+      promise.set_value(std::move(typed_response));
+      callback(std::move(future));
+    } else if (std::holds_alternative<CallbackWithRequestTypeValueVariant>(value)) {
+      auto & inner = std::get<CallbackWithRequestTypeValueVariant>(value);
+      const auto & callback = std::get<CallbackWithRequestType>(inner);
+      auto & promise = std::get<PromiseWithRequest>(inner);
+      auto & future = std::get<SharedFutureWithRequest>(inner);
+      auto & request = std::get<SharedRequest>(inner);
+      promise.set_value(std::make_pair(std::move(request), std::move(typed_response)));
+      callback(std::move(future));
+    }
   }
 
-  SharedFuture
+  /// Send a request to the service server.
+  /**
+   * This method returns a `FutureAndRequestId` instance
+   * that can be passed to Executor::spin_until_future_complete() to
+   * wait until it has been completed.
+   *
+   * If the future never completes,
+   * e.g. the call to Executor::spin_until_future_complete() times out,
+   * Client::remove_pending_request() must be called to clean the client internal state.
+   * Not doing so will make the `Client` instance to use more memory each time a response is not
+   * received from the service server.
+   *
+   * ```cpp
+   * auto future = client->async_send_request(my_request);
+   * if (
+   *   rclcpp::FutureReturnCode::TIMEOUT ==
+   *   executor->spin_until_future_complete(future, timeout))
+   * {
+   *   client->remove_pending_request(future);
+   *   // handle timeout
+   * } else {
+   *   handle_response(future.get());
+   * }
+   * ```
+   *
+   * \param[in] request request to be send.
+   * \return a FutureAndRequestId instance.
+   */
+  FutureAndRequestId
   async_send_request(SharedRequest request)
   {
-    return async_send_request(request, [](SharedFuture) {});
+    Promise promise;
+    auto future = promise.get_future();
+    auto req_id = async_send_request_impl(
+      *request,
+      std::move(promise));
+    return FutureAndRequestId(std::move(future), req_id);
   }
 
+  /// Send a request to the service server and schedule a callback in the executor.
+  /**
+   * Similar to the previous overload, but a callback will automatically be called when a response is received.
+   *
+   * If the callback is never called, because we never got a reply for the service server, remove_pending_request()
+   * has to be called with the returned request id or prune_pending_requests().
+   * Not doing so will make the `Client` instance use more memory each time a response is not
+   * received from the service server.
+   * In this case, it's convenient to setup a timer to cleanup the pending requests.
+   * See for example the `examples_rclcpp_async_client` package in https://github.com/ros2/examples.
+   *
+   * \param[in] request request to be send.
+   * \param[in] cb callback that will be called when we get a response for this request.
+   * \return the request id representing the request just sent.
+   */
   template<
     typename CallbackT,
     typename std::enable_if<
@@ -329,23 +639,28 @@ public:
       >::value
     >::type * = nullptr
   >
-  SharedFuture
+  SharedFutureAndRequestId
   async_send_request(SharedRequest request, CallbackT && cb)
   {
-    std::lock_guard<std::mutex> lock(pending_requests_mutex_);
-    int64_t sequence_number;
-    rcl_ret_t ret = rcl_send_request(get_client_handle().get(), request.get(), &sequence_number);
-    if (RCL_RET_OK != ret) {
-      rclcpp::exceptions::throw_from_rcl_error(ret, "failed to send request");
-    }
-
-    SharedPromise call_promise = std::make_shared<Promise>();
-    SharedFuture f(call_promise->get_future());
-    pending_requests_[sequence_number] =
-      std::make_tuple(call_promise, std::forward<CallbackType>(cb), f);
-    return f;
+    Promise promise;
+    auto shared_future = promise.get_future().share();
+    auto req_id = async_send_request_impl(
+      *request,
+      std::make_tuple(
+        CallbackType{std::forward<CallbackT>(cb)},
+        shared_future,
+        std::move(promise)));
+    return SharedFutureAndRequestId{std::move(shared_future), req_id};
   }
 
+  /// Send a request to the service server and schedule a callback in the executor.
+  /**
+   * Similar to the previous method, but you can get both the request and response in the callback.
+   *
+   * \param[in] request request to be send.
+   * \param[in] cb callback that will be called when we get a response for this request.
+   * \return the request id representing the request just sent.
+   */
   template<
     typename CallbackT,
     typename std::enable_if<
@@ -355,28 +670,165 @@ public:
       >::value
     >::type * = nullptr
   >
-  SharedFutureWithRequest
+  SharedFutureWithRequestAndRequestId
   async_send_request(SharedRequest request, CallbackT && cb)
   {
-    SharedPromiseWithRequest promise = std::make_shared<PromiseWithRequest>();
-    SharedFutureWithRequest future_with_request(promise->get_future());
-
-    auto wrapping_cb = [future_with_request, promise, request,
-        cb = std::forward<CallbackWithRequestType>(cb)](SharedFuture future) {
-        auto response = future.get();
-        promise->set_value(std::make_pair(request, response));
-        cb(future_with_request);
-      };
-
-    async_send_request(request, wrapping_cb);
-
-    return future_with_request;
+    PromiseWithRequest promise;
+    auto shared_future = promise.get_future().share();
+    auto req_id = async_send_request_impl(
+      *request,
+      std::make_tuple(
+        CallbackWithRequestType{std::forward<CallbackT>(cb)},
+        request,
+        shared_future,
+        std::move(promise)));
+    return SharedFutureWithRequestAndRequestId{std::move(shared_future), req_id};
+  }
+
+  /// Cleanup a pending request.
+  /**
+   * This notifies the client that we have waited long enough for a response from the server
+   * to come, we have given up and we are not waiting for a response anymore.
+   *
+   * Not calling this will make the client start using more memory for each request
+   * that never got a reply from the server.
+   *
+   * \param[in] request_id request id returned by async_send_request().
+   * \return true when a pending request was removed, false if not (e.g. a response was received).
+   */
+  bool
+  remove_pending_request(int64_t request_id)
+  {
+    std::lock_guard guard(pending_requests_mutex_);
+    return pending_requests_.erase(request_id) != 0u;
+  }
+
+  /// Cleanup a pending request.
+  /**
+   * Convenient overload, same as:
+   *
+   * `Client::remove_pending_request(this, future.request_id)`.
+   */
+  bool
+  remove_pending_request(const FutureAndRequestId & future)
+  {
+    return this->remove_pending_request(future.request_id);
+  }
+
+  /// Cleanup a pending request.
+  /**
+   * Convenient overload, same as:
+   *
+   * `Client::remove_pending_request(this, future.request_id)`.
+   */
+  bool
+  remove_pending_request(const SharedFutureAndRequestId & future)
+  {
+    return this->remove_pending_request(future.request_id);
+  }
+
+  /// Cleanup a pending request.
+  /**
+   * Convenient overload, same as:
+   *
+   * `Client::remove_pending_request(this, future.request_id)`.
+   */
+  bool
+  remove_pending_request(const SharedFutureWithRequestAndRequestId & future)
+  {
+    return this->remove_pending_request(future.request_id);
+  }
+
+  /// Clean all pending requests.
+  /**
+   * \return number of pending requests that were removed.
+   */
+  size_t
+  prune_pending_requests()
+  {
+    std::lock_guard guard(pending_requests_mutex_);
+    auto ret = pending_requests_.size();
+    pending_requests_.clear();
+    return ret;
+  }
+
+  /// Clean all pending requests older than a time_point.
+  /**
+   * \param[in] time_point Requests that were sent before this point are going to be removed.
+   * \param[inout] pruned_requests Removed requests id will be pushed to the vector
+   *  if a pointer is provided.
+   * \return number of pending requests that were removed.
+   */
+  template<typename AllocatorT = std::allocator<int64_t>>
+  size_t
+  prune_requests_older_than(
+    std::chrono::time_point<std::chrono::system_clock> time_point,
+    std::vector<int64_t, AllocatorT> * pruned_requests = nullptr)
+  {
+    std::lock_guard guard(pending_requests_mutex_);
+    auto old_size = pending_requests_.size();
+    for (auto it = pending_requests_.begin(), last = pending_requests_.end(); it != last; ) {
+      if (it->second.first < time_point) {
+        if (pruned_requests) {
+          pruned_requests->push_back(it->first);
+        }
+        it = pending_requests_.erase(it);
+      } else {
+        ++it;
+      }
+    }
+    return old_size - pending_requests_.size();
+  }
+
+protected:
+  using CallbackTypeValueVariant = std::tuple<CallbackType, SharedFuture, Promise>;
+  using CallbackWithRequestTypeValueVariant = std::tuple<
+    CallbackWithRequestType, SharedRequest, SharedFutureWithRequest, PromiseWithRequest>;
+
+  using CallbackInfoVariant = std::variant<
+    std::promise<SharedResponse>,
+    CallbackTypeValueVariant,
+    CallbackWithRequestTypeValueVariant>;
+
+  int64_t
+  async_send_request_impl(const Request & request, CallbackInfoVariant value)
+  {
+    int64_t sequence_number;
+    std::lock_guard<std::mutex> lock(pending_requests_mutex_);
+    rcl_ret_t ret = rcl_send_request(get_client_handle().get(), &request, &sequence_number);
+    if (RCL_RET_OK != ret) {
+      rclcpp::exceptions::throw_from_rcl_error(ret, "failed to send request");
+    }
+    pending_requests_.try_emplace(
+      sequence_number,
+      std::make_pair(std::chrono::system_clock::now(), std::move(value)));
+    return sequence_number;
+  }
+
+  std::optional<CallbackInfoVariant>
+  get_and_erase_pending_request(int64_t request_number)
+  {
+    std::unique_lock<std::mutex> lock(pending_requests_mutex_);
+    auto it = this->pending_requests_.find(request_number);
+    if (it == this->pending_requests_.end()) {
+      RCUTILS_LOG_DEBUG_NAMED(
+        "rclcpp",
+        "Received invalid sequence number. Ignoring...");
+      return std::nullopt;
+    }
+    std::optional<CallbackInfoVariant> value = std::move(it->second.second);
+    this->pending_requests_.erase(request_number);
+    return value;
   }
 
-private:
   RCLCPP_DISABLE_COPY(Client)
 
-  std::map<int64_t, std::tuple<SharedPromise, CallbackType, SharedFuture>> pending_requests_;
+  std::unordered_map<
+    int64_t,
+    std::pair<
+      std::chrono::time_point<std::chrono::system_clock>,
+      CallbackInfoVariant>>
+  pending_requests_;
   std::mutex pending_requests_mutex_;
 };
 

rclcpp/include/rclcpp/clock.hpp

@@ -19,6 +19,7 @@
 #include <memory>
 #include <mutex>
 
+#include "rclcpp/contexts/default_context.hpp"
 #include "rclcpp/macros.hpp"
 #include "rclcpp/time.hpp"
 #include "rclcpp/visibility_control.hpp"
@@ -59,6 +60,13 @@ public:
   /**
    * Initializes the clock instance with the given clock_type.
    *
+   * WARNING Don't instantiate a clock using RCL_ROS_TIME directly,
+   * unless you really know what you are doing. By default no TimeSource
+   * is attached to a new clock. This will lead to the unexpected behavior,
+   * that your RCL_ROS_TIME will run always on system time. If you want
+   * a RCL_ROS_TIME use Node::get_clock(), or make sure to attach a
+   * TimeSource yourself.
+   *
    * \param clock_type type of the clock.
    * \throws anything rclcpp::exceptions::throw_from_rcl_error can throw.
    */
@@ -78,6 +86,109 @@ public:
   Time
   now();
 
+  /**
+   * Sleep until a specified Time, according to clock type.
+   *
+   * Notes for RCL_ROS_TIME clock type:
+   *   - Can sleep forever if ros time is active and received clock never reaches `until`
+   *   - If ROS time enabled state changes during the sleep, this method will immediately return
+   *     false. There is not a consistent choice of sleeping time when the time source changes,
+   *     so this is up to the caller to call again if needed.
+   *
+   * \warning When using gcc < 10 or when using gcc >= 10 and pthreads lacks the function
+   *    `pthread_cond_clockwait`, steady clocks may sleep using the system clock.
+   *    If so, steady clock sleep times can be affected by system clock time jumps.
+   *    Depending on the steady clock's epoch and resolution in comparison to the system clock's,
+   *    an overflow when converting steady clock durations to system clock times may cause
+   *    undefined behavior.
+   *    For more info see these issues:
+   *    https://gcc.gnu.org/bugzilla/show_bug.cgi?id=41861
+   *    https://gcc.gnu.org/bugzilla/show_bug.cgi?id=58931
+   *
+   * \param until absolute time according to current clock type to sleep until.
+   * \param context the rclcpp context the clock should use to check that ROS is still initialized.
+   * \return true immediately if `until` is in the past
+   * \return true when the time `until` is reached
+   * \return false if time cannot be reached reliably, for example from shutdown or a change
+   *    of time source.
+   * \throws std::runtime_error if the context is invalid
+   * \throws std::runtime_error if `until` has a different clock type from this clock
+   */
+  RCLCPP_PUBLIC
+  bool
+  sleep_until(
+    Time until,
+    Context::SharedPtr context = contexts::get_global_default_context());
+
+  /**
+   * Sleep for a specified Duration.
+   *
+   * Equivalent to
+   *
+   * ```cpp
+   * clock->sleep_until(clock->now() + rel_time, context)
+   * ```
+   *
+   * The function will return immediately if `rel_time` is zero or negative.
+   *
+   * \param rel_time the length of time to sleep for.
+   * \param context the rclcpp context the clock should use to check that ROS is still initialized.
+   * \return true when the end time is reached
+   * \return false if time cannot be reached reliably, for example from shutdown or a change
+   *    of time source.
+   * \throws std::runtime_error if the context is invalid
+   */
+  RCLCPP_PUBLIC
+  bool
+  sleep_for(
+    Duration rel_time,
+    Context::SharedPtr context = contexts::get_global_default_context());
+
+  /**
+   * Check if the clock is started.
+   *
+   * A started clock is a clock that reflects non-zero time.
+   * Typically a clock will be unstarted if it is using RCL_ROS_TIME with ROS time and
+   * nothing has been published on the clock topic yet.
+   *
+   * \return true if clock is started
+   * \throws std::runtime_error if the clock is not rcl_clock_valid
+   */
+  RCLCPP_PUBLIC
+  bool
+  started();
+
+  /**
+   * Wait until clock to start.
+   *
+   * \rclcpp::Clock::started
+   * \param context the context to wait in
+   * \return true if clock was already started or became started
+   * \throws std::runtime_error if the context is invalid or clock is not rcl_clock_valid
+   */
+  RCLCPP_PUBLIC
+  bool
+  wait_until_started(Context::SharedPtr context = contexts::get_global_default_context());
+
+  /**
+   * Wait for clock to start, with timeout.
+   *
+   * The timeout is waited in steady time.
+   *
+   * \rclcpp::Clock::started
+   * \param timeout the maximum time to wait for.
+   * \param context the context to wait in.
+   * \param wait_tick_ns the time to wait between each iteration of the wait loop (in nanoseconds).
+   * \return true if clock was or became valid
+   * \throws std::runtime_error if the context is invalid or clock is not rcl_clock_valid
+   */
+  RCLCPP_PUBLIC
+  bool
+  wait_until_started(
+    const rclcpp::Duration & timeout,
+    Context::SharedPtr context = contexts::get_global_default_context(),
+    const rclcpp::Duration & wait_tick_ns = rclcpp::Duration(0, static_cast<uint32_t>(1e7)));
+
   /**
    * Returns the clock of the type `RCL_ROS_TIME` is active.
    *

rclcpp/include/rclcpp/context.hpp

@@ -26,6 +26,7 @@
 #include <unordered_set>
 #include <utility>
 #include <vector>
+#include <stdexcept>
 
 #include "rcl/context.h"
 #include "rcl/guard_condition.h"
@@ -48,17 +49,20 @@ public:
 /// Forward declare WeakContextsWrapper
 class WeakContextsWrapper;
 
-class OnShutdownCallbackHandle
+class ShutdownCallbackHandle
 {
   friend class Context;
 
 public:
-  using OnShutdownCallbackType = std::function<void ()>;
+  using ShutdownCallbackType = std::function<void ()>;
 
 private:
-  std::weak_ptr<OnShutdownCallbackType> callback;
+  std::weak_ptr<ShutdownCallbackType> callback;
 };
 
+using OnShutdownCallbackHandle = ShutdownCallbackHandle;
+using PreShutdownCallbackHandle = ShutdownCallbackHandle;
+
 /// Context which encapsulates shared state between nodes and other similar entities.
 /**
  * A context also represents the lifecycle between init and shutdown of rclcpp.
@@ -75,7 +79,7 @@ public:
    * Every context which is constructed is added to a global vector of contexts,
    * which is used by the signal handler to conditionally shutdown each context
    * on SIGINT.
-   * See the shutdown_on_sigint option in the InitOptions class.
+   * See the shutdown_on_signal option in the InitOptions class.
    */
   RCLCPP_PUBLIC
   Context();
@@ -93,7 +97,7 @@ public:
    * Note that this function does not setup any signal handlers, so if you want
    * it to be shutdown by the signal handler, then you need to either install
    * them manually with rclcpp::install_signal_handlers() or use rclcpp::init().
-   * In addition to installing the signal handlers, the shutdown_on_sigint
+   * In addition to installing the signal handlers, the shutdown_on_signal
    * of the InitOptions needs to be `true` for this context to be shutdown by
    * the signal handler, otherwise it will be passed over.
    *
@@ -124,7 +128,7 @@ public:
   void
   init(
     int argc,
-    char const * const argv[],
+    char const * const * argv,
     const rclcpp::InitOptions & init_options = rclcpp::InitOptions());
 
   /// Return true if the context is valid, otherwise false.
@@ -189,7 +193,7 @@ public:
   bool
   shutdown(const std::string & reason);
 
-  using OnShutdownCallback = OnShutdownCallbackHandle::OnShutdownCallbackType;
+  using OnShutdownCallback = OnShutdownCallbackHandle::ShutdownCallbackType;
 
   /// Add a on_shutdown callback to be called when shutdown is called for this context.
   /**
@@ -197,7 +201,7 @@ public:
    * to last step in shutdown().
    *
    * When shutdown occurs due to the signal handler, these callbacks are run
-   * asynchronoulsy in the dedicated singal handling thread.
+   * asynchronously in the dedicated singal handling thread.
    *
    * Also, shutdown() may be called from the destructor of this function.
    * Therefore, it is not safe to throw exceptions from these callbacks.
@@ -221,7 +225,7 @@ public:
    * to last step in shutdown().
    *
    * When shutdown occurs due to the signal handler, these callbacks are run
-   * asynchronously in the dedicated singal handling thread.
+   * asynchronously in the dedicated signal handling thread.
    *
    * Also, shutdown() may be called from the destructor of this function.
    * Therefore, it is not safe to throw exceptions from these callbacks.
@@ -249,6 +253,33 @@ public:
   bool
   remove_on_shutdown_callback(const OnShutdownCallbackHandle & callback_handle);
 
+  using PreShutdownCallback = PreShutdownCallbackHandle::ShutdownCallbackType;
+
+  /// Add a pre_shutdown callback to be called before shutdown is called for this context.
+  /**
+   * These callbacks will be called in the order they are added.
+   *
+   * When shutdown occurs due to the signal handler, these callbacks are run
+   * asynchronously in the dedicated signal handling thread.
+   *
+   * \param[in] callback the pre_shutdown callback to be registered
+   * \return the created callback handle
+   */
+  RCLCPP_PUBLIC
+  virtual
+  PreShutdownCallbackHandle
+  add_pre_shutdown_callback(PreShutdownCallback callback);
+
+  /// Remove an registered pre_shutdown callback.
+  /**
+   * \param[in] callback_handle the pre_shutdown callback handle to be removed.
+   * \return true if the callback is found and removed, otherwise false.
+   */
+  RCLCPP_PUBLIC
+  virtual
+  bool
+  remove_pre_shutdown_callback(const PreShutdownCallbackHandle & callback_handle);
+
   /// Return the shutdown callbacks.
   /**
    * Returned callbacks are a copy of the registered callbacks.
@@ -257,6 +288,14 @@ public:
   std::vector<OnShutdownCallback>
   get_on_shutdown_callbacks() const;
 
+  /// Return the pre-shutdown callbacks.
+  /**
+   * Returned callbacks are a copy of the registered callbacks.
+   */
+  RCLCPP_PUBLIC
+  std::vector<PreShutdownCallback>
+  get_pre_shutdown_callbacks() const;
+
   /// Return the internal rcl context.
   RCLCPP_PUBLIC
   std::shared_ptr<rcl_context_t>
@@ -268,7 +307,7 @@ public:
    *
    *   - this context is shutdown()
    *   - this context is destructed (resulting in shutdown)
-   *   - this context has shutdown_on_sigint=true and SIGINT occurs (resulting in shutdown)
+   *   - this context has shutdown_on_signal=true and SIGINT/SIGTERM occurs (resulting in shutdown)
    *   - interrupt_all_sleep_for() is called
    *
    * \param[in] nanoseconds A std::chrono::duration representing how long to sleep for.
@@ -338,6 +377,9 @@ private:
   std::unordered_set<std::shared_ptr<OnShutdownCallback>> on_shutdown_callbacks_;
   mutable std::mutex on_shutdown_callbacks_mutex_;
 
+  std::unordered_set<std::shared_ptr<PreShutdownCallback>> pre_shutdown_callbacks_;
+  mutable std::mutex pre_shutdown_callbacks_mutex_;
+
   /// Condition variable for timed sleep (see sleep_for).
   std::condition_variable interrupt_condition_variable_;
   /// Mutex for protecting the global condition variable.
@@ -345,6 +387,29 @@ private:
 
   /// Keep shared ownership of global vector of weak contexts
   std::shared_ptr<WeakContextsWrapper> weak_contexts_;
+
+  enum class ShutdownType
+  {
+    pre_shutdown,
+    on_shutdown
+  };
+
+  using ShutdownCallback = ShutdownCallbackHandle::ShutdownCallbackType;
+
+  RCLCPP_LOCAL
+  ShutdownCallbackHandle
+  add_shutdown_callback(
+    ShutdownType shutdown_type,
+    ShutdownCallback callback);
+
+  RCLCPP_LOCAL
+  bool
+  remove_shutdown_callback(
+    ShutdownType shutdown_type,
+    const ShutdownCallbackHandle & callback_handle);
+
+  std::vector<rclcpp::Context::ShutdownCallback>
+  get_shutdown_callback(ShutdownType shutdown_type) const;
 };
 
 /// Return a copy of the list of context shared pointers.

rclcpp/include/rclcpp/create_publisher.hpp

@@ -92,7 +92,7 @@ template<
   typename NodeT>
 std::shared_ptr<PublisherT>
 create_publisher(
-  NodeT & node,
+  NodeT && node,
   const std::string & topic_name,
   const rclcpp::QoS & qos,
   const rclcpp::PublisherOptionsWithAllocator<AllocatorT> & options = (

rclcpp/include/rclcpp/detail/add_guard_condition_to_rcl_wait_set.hpp

@@ -0,0 +1,39 @@
+// 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__ADD_GUARD_CONDITION_TO_RCL_WAIT_SET_HPP_
+#define RCLCPP__DETAIL__ADD_GUARD_CONDITION_TO_RCL_WAIT_SET_HPP_
+
+#include "rclcpp/guard_condition.hpp"
+
+namespace rclcpp
+{
+namespace detail
+{
+
+/// Adds the guard condition to a waitset
+/**
+ * \param[in] wait_set reference to a wait set where to add the guard condition
+ * \param[in] guard_condition reference to the guard_condition to be added
+ */
+RCLCPP_PUBLIC
+void
+add_guard_condition_to_rcl_wait_set(
+  rcl_wait_set_t & wait_set,
+  const rclcpp::GuardCondition & guard_condition);
+
+}  // namespace detail
+}  // namespace rclcpp
+
+#endif  // RCLCPP__DETAIL__ADD_GUARD_CONDITION_TO_RCL_WAIT_SET_HPP_

rclcpp/include/rclcpp/detail/cpp_callback_trampoline.hpp

@@ -0,0 +1,68 @@
+// 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__CPP_CALLBACK_TRAMPOLINE_HPP_
+#define RCLCPP__DETAIL__CPP_CALLBACK_TRAMPOLINE_HPP_
+
+#include <functional>
+
+namespace rclcpp
+{
+
+namespace detail
+{
+
+/// Trampoline pattern for wrapping std::function into C-style callbacks.
+/**
+ * A common pattern in C is for a function to take a function pointer and a
+ * void pointer for "user data" which is passed to the function pointer when it
+ * is called from within C.
+ *
+ * It works by using the user data pointer to store a pointer to a
+ * std::function instance.
+ * So when called from C, this function will cast the user data to the right
+ * std::function type and call it.
+ *
+ * This should allow you to use free functions, lambdas with and without
+ * captures, and various kinds of std::bind instances.
+ *
+ * The interior of this function is likely to be executed within a C runtime,
+ * so no exceptions should be thrown at this point, and doing so results in
+ * undefined behavior.
+ *
+ * \tparam UserDataT Deduced type based on what is passed for user data,
+ *   usually this type is either `void *` or `const void *`.
+ * \tparam Args the arguments being passed to the callback
+ * \tparam ReturnT the return type of this function and the callback, default void
+ * \param user_data the function pointer, possibly type erased
+ * \param args the arguments to be forwarded to the callback
+ * \returns whatever the callback returns, if anything
+ */
+template<
+  typename UserDataT,
+  typename ... Args,
+  typename ReturnT = void
+>
+ReturnT
+cpp_callback_trampoline(UserDataT user_data, Args ... args) noexcept
+{
+  auto & actual_callback = *reinterpret_cast<const std::function<ReturnT(Args...)> *>(user_data);
+  return actual_callback(args ...);
+}
+
+}  // namespace detail
+
+}  // namespace rclcpp
+
+#endif  // RCLCPP__DETAIL__CPP_CALLBACK_TRAMPOLINE_HPP_

rclcpp/include/rclcpp/detail/mutex_two_priorities.hpp

@@ -1,76 +0,0 @@
-// 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/qos_parameters.hpp

@@ -104,6 +104,7 @@ declare_parameter_or_get(
   }
 }
 
+#ifdef DOXYGEN_ONLY
 /// \internal Declare QoS parameters for the given entity.
 /**
  * \tparam NodeT Node pointer or reference type.
@@ -116,12 +117,23 @@ declare_parameter_or_get(
  * \param default_qos User provided qos. It will be used as a default for the parameters declared.
  * \return qos profile based on the user provided parameter overrides.
  */
+template<typename NodeT, typename EntityQosParametersTraits>
+rclcpp::QoS
+  declare_qos_parameters(
+  const ::rclcpp::QosOverridingOptions & options,
+  NodeT & node,
+  const std::string & topic_name,
+  const ::rclcpp::QoS & default_qos,
+  EntityQosParametersTraits);
+
+#else
+
 template<typename NodeT, typename EntityQosParametersTraits>
 std::enable_if_t<
-  rclcpp::node_interfaces::has_node_parameters_interface<
+  (rclcpp::node_interfaces::has_node_parameters_interface<
     decltype(std::declval<typename rcpputils::remove_pointer<NodeT>::type>())>::value ||
   std::is_same<typename std::decay_t<NodeT>,
-  rclcpp::node_interfaces::NodeParametersInterface::SharedPtr>::value,
+  rclcpp::node_interfaces::NodeParametersInterface::SharedPtr>::value),
   rclcpp::QoS>
 declare_qos_parameters(
   const ::rclcpp::QosOverridingOptions & options,
@@ -204,6 +216,8 @@ declare_qos_parameters(
   return default_qos;
 }
 
+#endif
+
 /// \internal Helper function to get a rmw qos policy value from a string.
 #define RCLCPP_DETAIL_APPLY_QOS_OVERRIDE_FROM_PARAMETER_STRING( \
     kind_lower, kind_upper, parameter_value, rclcpp_qos) \

rclcpp/include/rclcpp/detail/subscription_callback_type_helper.hpp

@@ -38,6 +38,7 @@ namespace detail
  *
  * This issue, with the lambda's, can be demonstrated with this minimal program:
  *
+ * \code{.cpp}
  *   #include <functional>
  *   #include <memory>
  *
@@ -52,6 +53,7 @@ namespace detail
  *     std::function<void (std::shared_ptr<int>)> cb = [](std::shared_ptr<int>){};
  *     f(cb);
  *   }
+ * \endcode
  *
  * If this program ever starts working in a future version of C++, this class
  * may become redundant.

rclcpp/include/rclcpp/detail/template_contains.hpp

@@ -0,0 +1,47 @@
+// Copyright 2022 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__TEMPLATE_CONTAINS_HPP_
+#define RCLCPP__DETAIL__TEMPLATE_CONTAINS_HPP_
+
+#include <type_traits>
+
+namespace rclcpp
+{
+namespace detail
+{
+
+/// Template meta-function that checks if a given T is contained in the list Us.
+template<typename T, typename ... Us>
+struct template_contains;
+
+template<typename ... Args>
+inline constexpr bool template_contains_v = template_contains<Args ...>::value;
+
+template<typename T, typename NextT, typename ... Us>
+struct template_contains<T, NextT, Us ...>
+{
+  enum { value = (std::is_same_v<T, NextT>|| template_contains_v<T, Us ...>)};
+};
+
+template<typename T>
+struct template_contains<T>
+{
+  enum { value = false };
+};
+
+}  // namespace detail
+}  // namespace rclcpp
+
+#endif  // RCLCPP__DETAIL__TEMPLATE_CONTAINS_HPP_

rclcpp/include/rclcpp/detail/template_unique.hpp

@@ -0,0 +1,49 @@
+// Copyright 2022 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__TEMPLATE_UNIQUE_HPP_
+#define RCLCPP__DETAIL__TEMPLATE_UNIQUE_HPP_
+
+#include <type_traits>
+
+#include "rclcpp/detail/template_contains.hpp"
+
+namespace rclcpp
+{
+namespace detail
+{
+
+/// Template meta-function that checks if a given list Ts contains unique types.
+template<typename ... Ts>
+struct template_unique;
+
+template<typename ... Args>
+inline constexpr bool template_unique_v = template_unique<Args ...>::value;
+
+template<typename NextT, typename ... Ts>
+struct template_unique<NextT, Ts ...>
+{
+  enum { value = !template_contains_v<NextT, Ts ...>&& template_unique_v<Ts ...>};
+};
+
+template<typename T>
+struct template_unique<T>
+{
+  enum { value = true };
+};
+
+}  // namespace detail
+}  // namespace rclcpp
+
+#endif  // RCLCPP__DETAIL__TEMPLATE_UNIQUE_HPP_

rclcpp/include/rclcpp/detail/utilities.hpp

@@ -30,7 +30,7 @@ namespace detail
 
 std::vector<std::string>
 get_unparsed_ros_arguments(
-  int argc, char const * const argv[],
+  int argc, char const * const * argv,
   rcl_arguments_t * arguments,
   rcl_allocator_t allocator);
 

rclcpp/include/rclcpp/duration.hpp

@@ -38,13 +38,6 @@ public:
    */
   Duration(int32_t seconds, uint32_t nanoseconds);
 
-  /// Construct duration from the specified nanoseconds.
-  [[deprecated(
-    "Use Duration::from_nanoseconds instead or std::chrono_literals. For example:"
-    "rclcpp::Duration::from_nanoseconds(int64_variable);"
-    "rclcpp::Duration(0ns);")]]
-  explicit Duration(rcl_duration_value_t nanoseconds);
-
   /// Construct duration from the specified std::chrono::nanoseconds.
   explicit Duration(std::chrono::nanoseconds nanoseconds);
 

rclcpp/include/rclcpp/exceptions/exceptions.hpp

@@ -109,6 +109,8 @@ public:
   : std::runtime_error(msg) {}
 };
 
+typedef void (* reset_error_function_t)();
+
 /// 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
@@ -129,7 +131,7 @@ 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);
+  reset_error_function_t reset_error = rcl_reset_error);
 /* *INDENT-ON* */
 
 class RCLErrorBase
@@ -254,6 +256,23 @@ public:
   {}
 };
 
+/// Thrown if user attempts to create an uninitialized statically typed parameter
+/**
+ * (see https://github.com/ros2/rclcpp/issues/1691)
+ */
+class UninitializedStaticallyTypedParameterException : public std::runtime_error
+{
+public:
+  /// Construct an instance.
+  /**
+   * \param[in] name the name of the parameter.
+   */
+  RCLCPP_PUBLIC
+  explicit UninitializedStaticallyTypedParameterException(const std::string & name)
+  : std::runtime_error("Statically typed parameter '" + name + "' must be initialized.")
+  {}
+};
+
 /// Thrown if parameter is already declared.
 class ParameterAlreadyDeclaredException : public std::runtime_error
 {
@@ -289,7 +308,6 @@ public:
   /// Construct an instance.
   /**
    * \param[in] name the name of the parameter.
-   * \param[in] message custom exception message.
    */
   explicit ParameterUninitializedException(const std::string & name)
   : std::runtime_error("parameter '" + name + "' is not initialized")

rclcpp/include/rclcpp/executor.hpp

@@ -29,6 +29,7 @@
 
 #include "rcl/guard_condition.h"
 #include "rcl/wait.h"
+#include "rcpputils/scope_exit.hpp"
 
 #include "rclcpp/context.hpp"
 #include "rclcpp/contexts/default_context.hpp"
@@ -40,7 +41,6 @@
 #include "rclcpp/node_interfaces/node_base_interface.hpp"
 #include "rclcpp/utilities.hpp"
 #include "rclcpp/visibility_control.hpp"
-#include "rclcpp/scope_exit.hpp"
 
 namespace rclcpp
 {
@@ -305,7 +305,9 @@ public:
    * If the time that waitables take to be executed is longer than the period on which new waitables
    * become ready, this method will execute work repeatedly until `max_duration` has elapsed.
    *
-   * \param[in] max_duration The maximum amount of time to spend executing work. Must be positive.
+   * \param[in] max_duration The maximum amount of time to spend executing work, must be >= 0.
+   *   `0` is potentially block forever until no more work is available.
+   * \throw std::invalid_argument if max_duration is less than 0.
    * Note that spin_all() may take longer than this time as it only returns once max_duration has
    * been exceeded.
    */
@@ -354,7 +356,7 @@ public:
     if (spinning.exchange(true)) {
       throw std::runtime_error("spin_until_future_complete() called while already spinning");
     }
-    RCLCPP_SCOPE_EXIT(this->spinning.store(false); );
+    RCPPUTILS_SCOPE_EXIT(this->spinning.store(false); );
     while (rclcpp::ok(this->context_) && spinning.load()) {
       // Do one item of work.
       spin_once_impl(timeout_left);
@@ -401,6 +403,15 @@ public:
   void
   set_memory_strategy(memory_strategy::MemoryStrategy::SharedPtr memory_strategy);
 
+  /// Returns true if the executor is currently spinning.
+  /**
+   * This function can be called asynchronously from any thread.
+   * \return True if the executor is currently spinning.
+   */
+  RCLCPP_PUBLIC
+  bool
+  is_spinning();
+
 protected:
   RCLCPP_PUBLIC
   void
@@ -455,6 +466,7 @@ protected:
   /// Return true if the node has been added to this executor.
   /**
    * \param[in] node_ptr a shared pointer that points to a node base interface
+   * \param[in] weak_groups_to_nodes map to nodes to lookup
    * \return true if the node is associated with the executor, otherwise false
    */
   RCLCPP_PUBLIC
@@ -525,7 +537,7 @@ protected:
   std::atomic_bool spinning;
 
   /// Guard condition for signaling the rmw layer to wake up for special events.
-  rcl_guard_condition_t interrupt_guard_condition_ = rcl_get_zero_initialized_guard_condition();
+  rclcpp::GuardCondition interrupt_guard_condition_;
 
   std::shared_ptr<rclcpp::GuardCondition> shutdown_guard_condition_;
 
@@ -548,14 +560,14 @@ protected:
   virtual void
   spin_once_impl(std::chrono::nanoseconds timeout);
 
-  typedef std::map<rclcpp::node_interfaces::NodeBaseInterface::WeakPtr,
-      const rcl_guard_condition_t *,
-      std::owner_less<rclcpp::node_interfaces::NodeBaseInterface::WeakPtr>>
-    WeakNodesToGuardConditionsMap;
+  typedef std::map<rclcpp::CallbackGroup::WeakPtr,
+      const rclcpp::GuardCondition *,
+      std::owner_less<rclcpp::CallbackGroup::WeakPtr>>
+    WeakCallbackGroupsToGuardConditionsMap;
 
-  /// maps nodes to guard conditions
-  WeakNodesToGuardConditionsMap
-  weak_nodes_to_guard_conditions_ RCPPUTILS_TSA_GUARDED_BY(mutex_);
+  /// maps callback groups to guard conditions
+  WeakCallbackGroupsToGuardConditionsMap
+  weak_groups_to_guard_conditions_ RCPPUTILS_TSA_GUARDED_BY(mutex_);
 
   /// maps callback groups associated to nodes
   WeakCallbackGroupsToNodesMap

rclcpp/include/rclcpp/executors.hpp

@@ -107,7 +107,9 @@ spin_until_future_complete(
   const FutureT & future,
   std::chrono::duration<TimeRepT, TimeT> timeout = std::chrono::duration<TimeRepT, TimeT>(-1))
 {
-  rclcpp::executors::SingleThreadedExecutor executor;
+  rclcpp::ExecutorOptions options;
+  options.context = node_ptr->get_context();
+  rclcpp::executors::SingleThreadedExecutor executor(options);
   return executors::spin_node_until_future_complete<FutureT>(executor, node_ptr, future, timeout);
 }
 

rclcpp/include/rclcpp/executors/multi_threaded_executor.hpp

@@ -22,7 +22,6 @@
 #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"
@@ -53,7 +52,7 @@ public:
    * \param timeout maximum time to wait
    */
   RCLCPP_PUBLIC
-  MultiThreadedExecutor(
+  explicit MultiThreadedExecutor(
     const rclcpp::ExecutorOptions & options = rclcpp::ExecutorOptions(),
     size_t number_of_threads = 0,
     bool yield_before_execute = false,
@@ -82,12 +81,10 @@ protected:
 private:
   RCLCPP_DISABLE_COPY(MultiThreadedExecutor)
 
-  detail::MutexTwoPriorities wait_mutex_;
+  std::mutex wait_mutex_;
   size_t number_of_threads_;
   bool yield_before_execute_;
   std::chrono::nanoseconds next_exec_timeout_;
-
-  std::set<TimerBase::SharedPtr> scheduled_timers_;
 };
 
 }  // namespace executors

rclcpp/include/rclcpp/executors/static_executor_entities_collector.hpp

@@ -57,15 +57,13 @@ public:
   /**
    * \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);
+    rclcpp::memory_strategy::MemoryStrategy::SharedPtr memory_strategy);
 
   /// Finalize StaticExecutorEntitiesCollector to clear resources
   RCLCPP_PUBLIC
@@ -104,7 +102,7 @@ public:
    * \throws std::runtime_error if it couldn't add guard condition to wait set
    */
   RCLCPP_PUBLIC
-  bool
+  void
   add_to_wait_set(rcl_wait_set_t * wait_set) override;
 
   RCLCPP_PUBLIC
@@ -301,7 +299,8 @@ private:
 
   /// Return true if the node belongs to the collector
   /**
-   * \param[in] group_ptr a node base interface shared pointer
+   * \param[in] node_ptr a node base interface shared pointer
+   * \param[in] weak_groups_to_nodes map to nodes to lookup
    * \return boolean whether a node belongs the collector
    */
   bool
@@ -330,7 +329,7 @@ private:
   WeakCallbackGroupsToNodesMap weak_groups_to_nodes_associated_with_executor_;
 
   typedef std::map<rclcpp::node_interfaces::NodeBaseInterface::WeakPtr,
-      const rcl_guard_condition_t *,
+      const rclcpp::GuardCondition *,
       std::owner_less<rclcpp::node_interfaces::NodeBaseInterface::WeakPtr>>
     WeakNodesToGuardConditionsMap;
   WeakNodesToGuardConditionsMap weak_nodes_to_guard_conditions_;
@@ -338,6 +337,10 @@ private:
   /// List of weak nodes registered in the static executor
   std::list<rclcpp::node_interfaces::NodeBaseInterface::WeakPtr> weak_nodes_;
 
+  // Mutex to protect vector of new nodes.
+  std::mutex new_nodes_mutex_;
+  std::vector<rclcpp::node_interfaces::NodeBaseInterface::WeakPtr> new_nodes_;
+
   /// Wait set for managing entities that the rmw layer waits on.
   rcl_wait_set_t * p_wait_set_ = nullptr;
 

rclcpp/include/rclcpp/executors/static_single_threaded_executor.hpp

@@ -99,9 +99,10 @@ public:
 
   /// Static executor implementation of spin all
   /**
-   * This non-blocking function will execute entities until
-   * timeout or no more work available. If new entities get ready
-   * while executing work available, they will be executed
+   * This non-blocking function will execute entities until timeout (must be >= 0)
+   * or no more work available.
+   * If timeout is `0`, potentially it blocks forever until no more work is available.
+   * If new entities get ready while executing work available, they will be executed
    * as long as the timeout hasn't expired.
    *
    * Example:

rclcpp/include/rclcpp/experimental/buffers/intra_process_buffer.hpp

@@ -16,6 +16,7 @@
 #define RCLCPP__EXPERIMENTAL__BUFFERS__INTRA_PROCESS_BUFFER_HPP_
 
 #include <memory>
+#include <stdexcept>
 #include <type_traits>
 #include <utility>
 

rclcpp/include/rclcpp/experimental/buffers/ring_buffer_implementation.hpp

@@ -15,10 +15,6 @@
 #ifndef RCLCPP__EXPERIMENTAL__BUFFERS__RING_BUFFER_IMPLEMENTATION_HPP_
 #define RCLCPP__EXPERIMENTAL__BUFFERS__RING_BUFFER_IMPLEMENTATION_HPP_
 
-#include <algorithm>
-#include <cstddef>
-#include <cstdint>
-#include <memory>
 #include <mutex>
 #include <stdexcept>
 #include <utility>
@@ -90,8 +86,7 @@ public:
     std::lock_guard<std::mutex> lock(mutex_);
 
     if (!has_data_()) {
-      RCLCPP_ERROR(rclcpp::get_logger("rclcpp"), "Calling dequeue on empty intra-process buffer");
-      throw std::runtime_error("Calling dequeue on empty intra-process buffer");
+      return BufferT();
     }
 
     auto request = std::move(ring_buffer_[read_index_]);

rclcpp/include/rclcpp/experimental/create_intra_process_buffer.hpp

@@ -16,11 +16,9 @@
 #define RCLCPP__EXPERIMENTAL__CREATE_INTRA_PROCESS_BUFFER_HPP_
 
 #include <memory>
-#include <type_traits>
+#include <stdexcept>
 #include <utility>
 
-#include "rcl/subscription.h"
-
 #include "rclcpp/experimental/buffers/intra_process_buffer.hpp"
 #include "rclcpp/experimental/buffers/ring_buffer_implementation.hpp"
 #include "rclcpp/intra_process_buffer_type.hpp"

rclcpp/include/rclcpp/experimental/executable_list.hpp

@@ -15,7 +15,6 @@
 #ifndef RCLCPP__EXPERIMENTAL__EXECUTABLE_LIST_HPP_
 #define RCLCPP__EXPERIMENTAL__EXECUTABLE_LIST_HPP_
 
-#include <memory>
 #include <vector>
 
 #include "rclcpp/client.hpp"

rclcpp/include/rclcpp/experimental/intra_process_manager.hpp

@@ -19,18 +19,16 @@
 
 #include <shared_mutex>
 
-#include <algorithm>
-#include <atomic>
-#include <cstdint>
-#include <exception>
-#include <map>
+#include <iterator>
 #include <memory>
-#include <string>
+#include <stdexcept>
 #include <unordered_map>
 #include <utility>
 #include <vector>
+#include <typeinfo>
 
 #include "rclcpp/allocator/allocator_deleter.hpp"
+#include "rclcpp/experimental/ros_message_intra_process_buffer.hpp"
 #include "rclcpp/experimental/subscription_intra_process.hpp"
 #include "rclcpp/experimental/subscription_intra_process_base.hpp"
 #include "rclcpp/experimental/subscription_intra_process_buffer.hpp"
@@ -38,6 +36,7 @@
 #include "rclcpp/logging.hpp"
 #include "rclcpp/macros.hpp"
 #include "rclcpp/publisher_base.hpp"
+#include "rclcpp/type_adapter.hpp"
 #include "rclcpp/visibility_control.hpp"
 
 namespace rclcpp
@@ -173,11 +172,14 @@ public:
    *
    * \param intra_process_publisher_id the id of the publisher of this message.
    * \param message the message that is being stored.
+   * \param allocator for allocations when buffering messages.
    */
   template<
     typename MessageT,
-    typename Alloc = std::allocator<void>,
-    typename Deleter = std::default_delete<MessageT>>
+    typename ROSMessageType,
+    typename Alloc,
+    typename Deleter = std::default_delete<MessageT>
+  >
   void
   do_intra_process_publish(
     uint64_t intra_process_publisher_id,
@@ -203,7 +205,7 @@ 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, Alloc, Deleter>(
+      this->template add_shared_msg_to_buffers<MessageT, Alloc, Deleter, ROSMessageType>(
         msg, sub_ids.take_shared_subscriptions);
     } else if (!sub_ids.take_ownership_subscriptions.empty() && // NOLINT
       sub_ids.take_shared_subscriptions.size() <= 1)
@@ -217,8 +219,7 @@ public:
         concatenated_vector.end(),
         sub_ids.take_ownership_subscriptions.begin(),
         sub_ids.take_ownership_subscriptions.end());
-
-      this->template add_owned_msg_to_buffers<MessageT, Alloc, Deleter>(
+      this->template add_owned_msg_to_buffers<MessageT, Alloc, Deleter, ROSMessageType>(
         std::move(message),
         concatenated_vector,
         allocator);
@@ -229,17 +230,19 @@ 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, Alloc, Deleter>(
+      this->template add_shared_msg_to_buffers<MessageT, Alloc, Deleter, ROSMessageType>(
         shared_msg, sub_ids.take_shared_subscriptions);
-      this->template add_owned_msg_to_buffers<MessageT, Alloc, Deleter>(
+      this->template add_owned_msg_to_buffers<MessageT, Alloc, Deleter, ROSMessageType>(
         std::move(message), sub_ids.take_ownership_subscriptions, allocator);
     }
   }
 
   template<
     typename MessageT,
-    typename Alloc = std::allocator<void>,
-    typename Deleter = std::default_delete<MessageT>>
+    typename ROSMessageType,
+    typename Alloc,
+    typename Deleter = std::default_delete<MessageT>
+  >
   std::shared_ptr<const MessageT>
   do_intra_process_publish_and_return_shared(
     uint64_t intra_process_publisher_id,
@@ -265,7 +268,7 @@ 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, Alloc, Deleter>(
+        this->template add_shared_msg_to_buffers<MessageT, Alloc, Deleter, ROSMessageType>(
           shared_msg, sub_ids.take_shared_subscriptions);
       }
       return shared_msg;
@@ -275,17 +278,16 @@ 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, Alloc, Deleter>(
+        this->template add_shared_msg_to_buffers<MessageT, Alloc, Deleter, ROSMessageType>(
           shared_msg,
           sub_ids.take_shared_subscriptions);
       }
       if (!sub_ids.take_ownership_subscriptions.empty()) {
-        this->template add_owned_msg_to_buffers<MessageT, Alloc, Deleter>(
+        this->template add_owned_msg_to_buffers<MessageT, Alloc, Deleter, ROSMessageType>(
           std::move(message),
           sub_ids.take_ownership_subscriptions,
           allocator);
       }
-
       return shared_msg;
     }
   }
@@ -338,41 +340,83 @@ private:
   template<
     typename MessageT,
     typename Alloc,
-    typename Deleter>
+    typename Deleter,
+    typename ROSMessageType>
   void
   add_shared_msg_to_buffers(
     std::shared_ptr<const MessageT> message,
     std::vector<uint64_t> subscription_ids)
   {
+    using ROSMessageTypeAllocatorTraits = allocator::AllocRebind<ROSMessageType, Alloc>;
+    using ROSMessageTypeAllocator = typename ROSMessageTypeAllocatorTraits::allocator_type;
+    using ROSMessageTypeDeleter = allocator::Deleter<ROSMessageTypeAllocator, ROSMessageType>;
+
+    using PublishedType = typename rclcpp::TypeAdapter<MessageT>::custom_type;
+    using PublishedTypeAllocatorTraits = allocator::AllocRebind<PublishedType, Alloc>;
+    using PublishedTypeAllocator = typename PublishedTypeAllocatorTraits::allocator_type;
+    using PublishedTypeDeleter = allocator::Deleter<PublishedTypeAllocator, PublishedType>;
+
     for (auto id : subscription_ids) {
       auto subscription_it = subscriptions_.find(id);
       if (subscription_it == subscriptions_.end()) {
         throw std::runtime_error("subscription has unexpectedly gone out of scope");
       }
       auto subscription_base = subscription_it->second.lock();
-      if (subscription_base) {
-        auto subscription = std::dynamic_pointer_cast<
-          rclcpp::experimental::SubscriptionIntraProcessBuffer<MessageT, Alloc, Deleter>
-          >(subscription_base);
-        if (nullptr == subscription) {
-          throw std::runtime_error(
-                  "failed to dynamic cast SubscriptionIntraProcessBase to "
-                  "SubscriptionIntraProcessBuffer<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);
-      } else {
+      if (subscription_base == nullptr) {
         subscriptions_.erase(id);
+        continue;
+      }
+
+      auto subscription = std::dynamic_pointer_cast<
+        rclcpp::experimental::SubscriptionIntraProcessBuffer<PublishedType,
+        PublishedTypeAllocator, PublishedTypeDeleter, ROSMessageType>
+        >(subscription_base);
+      if (subscription != nullptr) {
+        subscription->provide_intra_process_data(message);
+        continue;
+      }
+
+      auto ros_message_subscription = std::dynamic_pointer_cast<
+        rclcpp::experimental::SubscriptionROSMsgIntraProcessBuffer<ROSMessageType,
+        ROSMessageTypeAllocator, ROSMessageTypeDeleter>
+        >(subscription_base);
+      if (nullptr == ros_message_subscription) {
+        throw std::runtime_error(
+                "failed to dynamic cast SubscriptionIntraProcessBase to "
+                "SubscriptionIntraProcessBuffer<MessageT, Alloc, Deleter>, or to "
+                "SubscriptionROSMsgIntraProcessBuffer<ROSMessageType,ROSMessageTypeAllocator,"
+                "ROSMessageTypeDeleter> which can happen when the publisher and "
+                "subscription use different allocator types, which is not supported");
+      }
+
+      if constexpr (rclcpp::TypeAdapter<MessageT>::is_specialized::value) {
+        ROSMessageType ros_msg;
+        rclcpp::TypeAdapter<MessageT>::convert_to_ros_message(*message, ros_msg);
+        ros_message_subscription->provide_intra_process_message(
+          std::make_shared<ROSMessageType>(ros_msg));
+      } else {
+        if constexpr (std::is_same<MessageT, ROSMessageType>::value) {
+          ros_message_subscription->provide_intra_process_message(message);
+        } else {
+          if constexpr (std::is_same<typename rclcpp::TypeAdapter<MessageT,
+            ROSMessageType>::ros_message_type, ROSMessageType>::value)
+          {
+            ROSMessageType ros_msg;
+            rclcpp::TypeAdapter<MessageT, ROSMessageType>::convert_to_ros_message(
+              *message, ros_msg);
+            ros_message_subscription->provide_intra_process_message(
+              std::make_shared<ROSMessageType>(ros_msg));
+          }
+        }
       }
     }
   }
 
   template<
     typename MessageT,
-    typename Alloc = std::allocator<void>,
-    typename Deleter = std::default_delete<MessageT>>
+    typename Alloc,
+    typename Deleter,
+    typename ROSMessageType>
   void
   add_owned_msg_to_buffers(
     std::unique_ptr<MessageT, Deleter> message,
@@ -382,39 +426,88 @@ private:
     using MessageAllocTraits = allocator::AllocRebind<MessageT, Alloc>;
     using MessageUniquePtr = std::unique_ptr<MessageT, Deleter>;
 
+    using ROSMessageTypeAllocatorTraits = allocator::AllocRebind<ROSMessageType, Alloc>;
+    using ROSMessageTypeAllocator = typename ROSMessageTypeAllocatorTraits::allocator_type;
+    using ROSMessageTypeDeleter = allocator::Deleter<ROSMessageTypeAllocator, ROSMessageType>;
+
+    using PublishedType = typename rclcpp::TypeAdapter<MessageT>::custom_type;
+    using PublishedTypeAllocatorTraits = allocator::AllocRebind<PublishedType, Alloc>;
+    using PublishedTypeAllocator = typename PublishedTypeAllocatorTraits::allocator_type;
+    using PublishedTypeDeleter = allocator::Deleter<PublishedTypeAllocator, PublishedType>;
+
     for (auto it = subscription_ids.begin(); it != subscription_ids.end(); it++) {
       auto subscription_it = subscriptions_.find(*it);
       if (subscription_it == subscriptions_.end()) {
         throw std::runtime_error("subscription has unexpectedly gone out of scope");
       }
       auto subscription_base = subscription_it->second.lock();
-      if (subscription_base) {
-        auto subscription = std::dynamic_pointer_cast<
-          rclcpp::experimental::SubscriptionIntraProcessBuffer<MessageT, Alloc, Deleter>
-          >(subscription_base);
-        if (nullptr == subscription) {
-          throw std::runtime_error(
-                  "failed to dynamic cast SubscriptionIntraProcessBase to "
-                  "SubscriptionIntraProcessBuffer<MessageT, Alloc, Deleter>, which "
-                  "can happen when the publisher and subscription use different "
-                  "allocator types, which is not supported");
-        }
+      if (subscription_base == nullptr) {
+        subscriptions_.erase(subscription_it);
+        continue;
+      }
 
+      auto subscription = std::dynamic_pointer_cast<
+        rclcpp::experimental::SubscriptionIntraProcessBuffer<PublishedType,
+        PublishedTypeAllocator, PublishedTypeDeleter, ROSMessageType>
+        >(subscription_base);
+      if (subscription != nullptr) {
         if (std::next(it) == subscription_ids.end()) {
           // If this is the last subscription, give up ownership
-          subscription->provide_intra_process_message(std::move(message));
+          subscription->provide_intra_process_data(std::move(message));
+          // Last message delivered, break from for loop
+          break;
         } else {
           // Copy the message since we have additional subscriptions to serve
-          MessageUniquePtr copy_message;
           Deleter deleter = message.get_deleter();
           auto ptr = MessageAllocTraits::allocate(allocator, 1);
           MessageAllocTraits::construct(allocator, ptr, *message);
-          copy_message = MessageUniquePtr(ptr, deleter);
 
-          subscription->provide_intra_process_message(std::move(copy_message));
+          subscription->provide_intra_process_data(std::move(MessageUniquePtr(ptr, deleter)));
         }
+
+        continue;
+      }
+
+      auto ros_message_subscription = std::dynamic_pointer_cast<
+        rclcpp::experimental::SubscriptionROSMsgIntraProcessBuffer<ROSMessageType,
+        ROSMessageTypeAllocator, ROSMessageTypeDeleter>
+        >(subscription_base);
+      if (nullptr == ros_message_subscription) {
+        throw std::runtime_error(
+                "failed to dynamic cast SubscriptionIntraProcessBase to "
+                "SubscriptionIntraProcessBuffer<MessageT, Alloc, Deleter>, or to "
+                "SubscriptionROSMsgIntraProcessBuffer<ROSMessageType,ROSMessageTypeAllocator,"
+                "ROSMessageTypeDeleter> which can happen when the publisher and "
+                "subscription use different allocator types, which is not supported");
+      }
+
+      if constexpr (rclcpp::TypeAdapter<MessageT, ROSMessageType>::is_specialized::value) {
+        ROSMessageTypeAllocator ros_message_alloc(allocator);
+        auto ptr = ROSMessageTypeAllocatorTraits::allocate(ros_message_alloc, 1);
+        ROSMessageTypeAllocatorTraits::construct(ros_message_alloc, ptr);
+        ROSMessageTypeDeleter deleter;
+        allocator::set_allocator_for_deleter(&deleter, &allocator);
+        rclcpp::TypeAdapter<MessageT, ROSMessageType>::convert_to_ros_message(*message, *ptr);
+        auto ros_msg = std::unique_ptr<ROSMessageType, ROSMessageTypeDeleter>(ptr, deleter);
+        ros_message_subscription->provide_intra_process_message(std::move(ros_msg));
       } else {
-        subscriptions_.erase(subscription_it);
+        if constexpr (std::is_same<MessageT, ROSMessageType>::value) {
+          if (std::next(it) == subscription_ids.end()) {
+            // If this is the last subscription, give up ownership
+            ros_message_subscription->provide_intra_process_message(std::move(message));
+            // Last message delivered, break from for loop
+            break;
+          } else {
+            // Copy the message since we have additional subscriptions to serve
+            Deleter deleter = message.get_deleter();
+            allocator::set_allocator_for_deleter(&deleter, &allocator);
+            auto ptr = MessageAllocTraits::allocate(allocator, 1);
+            MessageAllocTraits::construct(allocator, ptr, *message);
+
+            ros_message_subscription->provide_intra_process_message(
+              std::move(MessageUniquePtr(ptr, deleter)));
+          }
+        }
       }
     }
   }

rclcpp/include/rclcpp/experimental/ros_message_intra_process_buffer.hpp

@@ -0,0 +1,68 @@
+// 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__EXPERIMENTAL__ROS_MESSAGE_INTRA_PROCESS_BUFFER_HPP_
+#define RCLCPP__EXPERIMENTAL__ROS_MESSAGE_INTRA_PROCESS_BUFFER_HPP_
+
+#include <memory>
+#include <string>
+
+#include "rcl/error_handling.h"
+
+#include "rclcpp/any_subscription_callback.hpp"
+#include "rclcpp/context.hpp"
+#include "rclcpp/experimental/subscription_intra_process_base.hpp"
+#include "tracetools/tracetools.h"
+
+namespace rclcpp
+{
+namespace experimental
+{
+
+template<
+  typename RosMessageT,
+  typename Alloc = std::allocator<void>,
+  typename Deleter = std::default_delete<void>
+>
+class SubscriptionROSMsgIntraProcessBuffer : public SubscriptionIntraProcessBase
+{
+public:
+  using ROSMessageTypeAllocatorTraits = allocator::AllocRebind<RosMessageT, Alloc>;
+  using ROSMessageTypeAllocator = typename ROSMessageTypeAllocatorTraits::allocator_type;
+  using ROSMessageTypeDeleter = allocator::Deleter<ROSMessageTypeAllocator, RosMessageT>;
+
+  using ConstMessageSharedPtr = std::shared_ptr<const RosMessageT>;
+  using MessageUniquePtr = std::unique_ptr<RosMessageT, ROSMessageTypeDeleter>;
+
+  SubscriptionROSMsgIntraProcessBuffer(
+    rclcpp::Context::SharedPtr context,
+    const std::string & topic_name,
+    const rclcpp::QoS & qos_profile)
+  : SubscriptionIntraProcessBase(context, topic_name, qos_profile)
+  {}
+
+  virtual ~SubscriptionROSMsgIntraProcessBuffer()
+  {}
+
+  virtual void
+  provide_intra_process_message(ConstMessageSharedPtr message) = 0;
+
+  virtual void
+  provide_intra_process_message(MessageUniquePtr message) = 0;
+};
+
+}  // namespace experimental
+}  // namespace rclcpp
+
+#endif  // RCLCPP__EXPERIMENTAL__ROS_MESSAGE_INTRA_PROCESS_BUFFER_HPP_

rclcpp/include/rclcpp/experimental/subscription_intra_process.hpp

@@ -15,25 +15,22 @@
 #ifndef RCLCPP__EXPERIMENTAL__SUBSCRIPTION_INTRA_PROCESS_HPP_
 #define RCLCPP__EXPERIMENTAL__SUBSCRIPTION_INTRA_PROCESS_HPP_
 
-#include <rmw/rmw.h>
+#include <rmw/types.h>
 
-#include <functional>
-#include <map>
 #include <memory>
 #include <stdexcept>
 #include <string>
+#include <type_traits>
 #include <utility>
 
-#include "rcl/error_handling.h"
+#include "rcl/types.h"
 
 #include "rclcpp/any_subscription_callback.hpp"
+#include "rclcpp/context.hpp"
 #include "rclcpp/experimental/buffers/intra_process_buffer.hpp"
-#include "rclcpp/experimental/create_intra_process_buffer.hpp"
-#include "rclcpp/experimental/subscription_intra_process_base.hpp"
 #include "rclcpp/experimental/subscription_intra_process_buffer.hpp"
 #include "rclcpp/qos.hpp"
 #include "rclcpp/type_support_decl.hpp"
-#include "rclcpp/waitable.hpp"
 #include "tracetools/tracetools.h"
 
 namespace rclcpp
@@ -43,40 +40,47 @@ namespace experimental
 
 template<
   typename MessageT,
-  typename Alloc = std::allocator<void>,
-  typename Deleter = std::default_delete<MessageT>,
-  typename CallbackMessageT = MessageT>
+  typename SubscribedType,
+  typename SubscribedTypeAlloc = std::allocator<SubscribedType>,
+  typename SubscribedTypeDeleter = std::default_delete<SubscribedType>,
+  typename ROSMessageType = SubscribedType,
+  typename Alloc = std::allocator<void>
+>
 class SubscriptionIntraProcess
   : public SubscriptionIntraProcessBuffer<
-    MessageT,
-    Alloc,
-    Deleter
+    SubscribedType,
+    SubscribedTypeAlloc,
+    SubscribedTypeDeleter,
+    ROSMessageType
   >
 {
   using SubscriptionIntraProcessBufferT = SubscriptionIntraProcessBuffer<
-    MessageT,
-    Alloc,
-    Deleter
+    SubscribedType,
+    SubscribedTypeAlloc,
+    SubscribedTypeDeleter,
+    ROSMessageType
   >;
 
 public:
   RCLCPP_SMART_PTR_DEFINITIONS(SubscriptionIntraProcess)
 
-  using MessageAllocTraits = typename SubscriptionIntraProcessBufferT::MessageAllocTraits;
-  using MessageAlloc = typename SubscriptionIntraProcessBufferT::MessageAlloc;
-  using ConstMessageSharedPtr = typename SubscriptionIntraProcessBufferT::ConstMessageSharedPtr;
-  using MessageUniquePtr = typename SubscriptionIntraProcessBufferT::MessageUniquePtr;
+  using MessageAllocTraits =
+    typename SubscriptionIntraProcessBufferT::SubscribedTypeAllocatorTraits;
+  using MessageAlloc = typename SubscriptionIntraProcessBufferT::SubscribedTypeAllocator;
+  using ConstMessageSharedPtr = typename SubscriptionIntraProcessBufferT::ConstDataSharedPtr;
+  using MessageUniquePtr = typename SubscriptionIntraProcessBufferT::SubscribedTypeUniquePtr;
   using BufferUniquePtr = typename SubscriptionIntraProcessBufferT::BufferUniquePtr;
 
   SubscriptionIntraProcess(
-    AnySubscriptionCallback<CallbackMessageT, Alloc> callback,
+    AnySubscriptionCallback<MessageT, Alloc> callback,
     std::shared_ptr<Alloc> allocator,
     rclcpp::Context::SharedPtr context,
     const std::string & topic_name,
     const rclcpp::QoS & qos_profile,
     rclcpp::IntraProcessBufferType buffer_type)
-  : SubscriptionIntraProcessBuffer<MessageT, Alloc, Deleter>(
-      allocator,
+  : SubscriptionIntraProcessBuffer<SubscribedType, SubscribedTypeAlloc,
+      SubscribedTypeDeleter, ROSMessageType>(
+      std::make_shared<SubscribedTypeAlloc>(*allocator),
       context,
       topic_name,
       qos_profile,
@@ -98,16 +102,29 @@ public:
   virtual ~SubscriptionIntraProcess() = default;
 
   std::shared_ptr<void>
-  take_data()
+  take_data() override
   {
     ConstMessageSharedPtr shared_msg;
     MessageUniquePtr unique_msg;
 
     if (any_callback_.use_take_shared_method()) {
       shared_msg = this->buffer_->consume_shared();
+      if (!shared_msg) {
+        return nullptr;
+      }
     } else {
       unique_msg = this->buffer_->consume_unique();
+      if (!unique_msg) {
+        return nullptr;
+      }
     }
+
+    if (this->buffer_->has_data()) {
+      // If there is data still to be processed, indicate to the
+      // executor or waitset by triggering the guard condition.
+      this->trigger_guard_condition();
+    }
+
     return std::static_pointer_cast<void>(
       std::make_shared<std::pair<ConstMessageSharedPtr, MessageUniquePtr>>(
         std::pair<ConstMessageSharedPtr, MessageUniquePtr>(
@@ -115,9 +132,9 @@ public:
     );
   }
 
-  void execute(std::shared_ptr<void> & data)
+  void execute(std::shared_ptr<void> & data) override
   {
-    execute_impl<MessageT>(data);
+    execute_impl<SubscribedType>(data);
   }
 
 protected:
@@ -134,7 +151,7 @@ protected:
   execute_impl(std::shared_ptr<void> & data)
   {
     if (!data) {
-      throw std::runtime_error("'data' is empty");
+      return;
     }
 
     rmw_message_info_t msg_info;
@@ -154,7 +171,7 @@ protected:
     shared_ptr.reset();
   }
 
-  AnySubscriptionCallback<CallbackMessageT, Alloc> any_callback_;
+  AnySubscriptionCallback<MessageT, Alloc> any_callback_;
 };
 
 }  // namespace experimental

rclcpp/include/rclcpp/experimental/subscription_intra_process_base.hpp

@@ -15,18 +15,17 @@
 #ifndef RCLCPP__EXPERIMENTAL__SUBSCRIPTION_INTRA_PROCESS_BASE_HPP_
 #define RCLCPP__EXPERIMENTAL__SUBSCRIPTION_INTRA_PROCESS_BASE_HPP_
 
-#include <rmw/rmw.h>
-
-#include <functional>
+#include <algorithm>
 #include <memory>
 #include <mutex>
 #include <string>
-#include <utility>
 
-#include "rcl/error_handling.h"
+#include "rcl/wait.h"
+#include "rmw/impl/cpp/demangle.hpp"
 
+#include "rclcpp/guard_condition.hpp"
+#include "rclcpp/logging.hpp"
 #include "rclcpp/qos.hpp"
-#include "rclcpp/type_support_decl.hpp"
 #include "rclcpp/waitable.hpp"
 
 namespace rclcpp
@@ -39,34 +38,48 @@ class SubscriptionIntraProcessBase : public rclcpp::Waitable
 public:
   RCLCPP_SMART_PTR_ALIASES_ONLY(SubscriptionIntraProcessBase)
 
+  enum class EntityType : std::size_t
+  {
+    Subscription,
+  };
+
   RCLCPP_PUBLIC
   SubscriptionIntraProcessBase(
+    rclcpp::Context::SharedPtr context,
     const std::string & topic_name,
     const rclcpp::QoS & qos_profile)
-  : topic_name_(topic_name), qos_profile_(qos_profile)
+  : gc_(context), topic_name_(topic_name), qos_profile_(qos_profile)
   {}
 
-  virtual ~SubscriptionIntraProcessBase() = default;
+  RCLCPP_PUBLIC
+  virtual ~SubscriptionIntraProcessBase();
 
   RCLCPP_PUBLIC
   size_t
-  get_number_of_ready_guard_conditions() {return 1;}
+  get_number_of_ready_guard_conditions() override {return 1;}
 
   RCLCPP_PUBLIC
-  bool
-  add_to_wait_set(rcl_wait_set_t * wait_set);
+  void
+  add_to_wait_set(rcl_wait_set_t * wait_set) override;
 
-  virtual bool
-  is_ready(rcl_wait_set_t * wait_set) = 0;
+  bool
+  is_ready(rcl_wait_set_t * wait_set) override = 0;
+
+  std::shared_ptr<void>
+  take_data() override = 0;
+
+  std::shared_ptr<void>
+  take_data_by_entity_id(size_t id) override
+  {
+    (void)id;
+    return take_data();
+  }
+
+  void
+  execute(std::shared_ptr<void> & data) override = 0;
 
   virtual
-  std::shared_ptr<void>
-  take_data() = 0;
-
-  virtual void
-  execute(std::shared_ptr<void> & data) = 0;
-
-  virtual bool
+  bool
   use_take_shared_method() const = 0;
 
   RCLCPP_PUBLIC
@@ -77,14 +90,108 @@ public:
   QoS
   get_actual_qos() const;
 
-protected:
-  std::recursive_mutex reentrant_mutex_;
-  rcl_guard_condition_t gc_;
+  /// Set a callback to be called when each new message arrives.
+  /**
+   * The callback receives a size_t which is the number of messages received
+   * since the last time this callback was called.
+   * Normally this is 1, but can be > 1 if messages were received before any
+   * callback was set.
+   *
+   * The callback also receives an int identifier argument.
+   * This is needed because a Waitable may be composed of several distinct entities,
+   * such as subscriptions, services, etc.
+   * The application should provide a generic callback function that will be then
+   * forwarded by the waitable to all of its entities.
+   * Before forwarding, a different value for the identifier argument will be
+   * bound to the function.
+   * This implies that the provided callback can use the identifier to behave
+   * differently depending on which entity triggered the waitable to become ready.
+   *
+   * Calling it again will clear any previously set callback.
+   *
+   * An exception will be thrown if the callback is not callable.
+   *
+   * This function is thread-safe.
+   *
+   * If you want more information available in the callback, like the subscription
+   * or other information, you may use a lambda with captures or std::bind.
+   *
+   * \param[in] callback functor to be called when a new message is received.
+   */
+  void
+  set_on_ready_callback(std::function<void(size_t, int)> callback) override
+  {
+    if (!callback) {
+      throw std::invalid_argument(
+              "The callback passed to set_on_ready_callback "
+              "is not callable.");
+    }
+
+    // Note: we bind the int identifier argument to this waitable's entity types
+    auto new_callback =
+      [callback, this](size_t number_of_events) {
+        try {
+          callback(number_of_events, static_cast<int>(EntityType::Subscription));
+        } catch (const std::exception & exception) {
+          RCLCPP_ERROR_STREAM(
+            // TODO(wjwwood): get this class access to the node logger it is associated with
+            rclcpp::get_logger("rclcpp"),
+            "rclcpp::SubscriptionIntraProcessBase@" << this <<
+              " caught " << rmw::impl::cpp::demangle(exception) <<
+              " exception in user-provided callback for the 'on ready' callback: " <<
+              exception.what());
+        } catch (...) {
+          RCLCPP_ERROR_STREAM(
+            rclcpp::get_logger("rclcpp"),
+            "rclcpp::SubscriptionIntraProcessBase@" << this <<
+              " caught unhandled exception in user-provided callback " <<
+              "for the 'on ready' callback");
+        }
+      };
+
+    std::lock_guard<std::recursive_mutex> lock(callback_mutex_);
+    on_new_message_callback_ = new_callback;
+
+    if (unread_count_ > 0) {
+      if (qos_profile_.history() == HistoryPolicy::KeepAll) {
+        on_new_message_callback_(unread_count_);
+      } else {
+        // Use qos profile depth as upper bound for unread_count_
+        on_new_message_callback_(std::min(unread_count_, qos_profile_.depth()));
+      }
+      unread_count_ = 0;
+    }
+  }
+
+  /// Unset the callback registered for new messages, if any.
+  void
+  clear_on_ready_callback() override
+  {
+    std::lock_guard<std::recursive_mutex> lock(callback_mutex_);
+    on_new_message_callback_ = nullptr;
+  }
+
+protected:
+  std::recursive_mutex callback_mutex_;
+  std::function<void(size_t)> on_new_message_callback_ {nullptr};
+  size_t unread_count_{0};
+  rclcpp::GuardCondition gc_;
 
-private:
   virtual void
   trigger_guard_condition() = 0;
 
+  void
+  invoke_on_new_message()
+  {
+    std::lock_guard<std::recursive_mutex> lock(this->callback_mutex_);
+    if (this->on_new_message_callback_) {
+      this->on_new_message_callback_(1);
+    } else {
+      this->unread_count_++;
+    }
+  }
+
+private:
   std::string topic_name_;
   QoS qos_profile_;
 };

rclcpp/include/rclcpp/experimental/subscription_intra_process_buffer.hpp

@@ -15,25 +15,21 @@
 #ifndef RCLCPP__EXPERIMENTAL__SUBSCRIPTION_INTRA_PROCESS_BUFFER_HPP_
 #define RCLCPP__EXPERIMENTAL__SUBSCRIPTION_INTRA_PROCESS_BUFFER_HPP_
 
-#include <rmw/rmw.h>
-
-#include <functional>
-#include <map>
 #include <memory>
-#include <stdexcept>
 #include <string>
+#include <stdexcept>
 #include <utility>
 
 #include "rcl/error_handling.h"
+#include "rcl/guard_condition.h"
+#include "rcl/wait.h"
 
-#include "rclcpp/any_subscription_callback.hpp"
 #include "rclcpp/experimental/buffers/intra_process_buffer.hpp"
 #include "rclcpp/experimental/create_intra_process_buffer.hpp"
 #include "rclcpp/experimental/subscription_intra_process_base.hpp"
+#include "rclcpp/experimental/ros_message_intra_process_buffer.hpp"
 #include "rclcpp/qos.hpp"
 #include "rclcpp/type_support_decl.hpp"
-#include "rclcpp/waitable.hpp"
-#include "tracetools/tracetools.h"
 
 namespace rclcpp
 {
@@ -41,24 +37,39 @@ namespace experimental
 {
 
 template<
-  typename MessageT,
-  typename Alloc = std::allocator<void>,
-  typename Deleter = std::default_delete<MessageT>
+  typename SubscribedType,
+  typename Alloc = std::allocator<SubscribedType>,
+  typename Deleter = std::default_delete<SubscribedType>,
+  /// MessageT::ros_message_type if MessageT is a TypeAdapter,
+  /// otherwise just MessageT.
+  typename ROSMessageType = SubscribedType
 >
-class SubscriptionIntraProcessBuffer : public SubscriptionIntraProcessBase
+class SubscriptionIntraProcessBuffer : public SubscriptionROSMsgIntraProcessBuffer<ROSMessageType,
+    typename allocator::AllocRebind<ROSMessageType, Alloc>::allocator_type,
+    allocator::Deleter<typename allocator::AllocRebind<ROSMessageType, Alloc>::allocator_type,
+    ROSMessageType>>
 {
 public:
   RCLCPP_SMART_PTR_DEFINITIONS(SubscriptionIntraProcessBuffer)
 
-  using MessageAllocTraits = allocator::AllocRebind<MessageT, Alloc>;
-  using MessageAlloc = typename MessageAllocTraits::allocator_type;
-  using ConstMessageSharedPtr = std::shared_ptr<const MessageT>;
-  using MessageUniquePtr = std::unique_ptr<MessageT, Deleter>;
+  using SubscribedTypeAllocatorTraits = allocator::AllocRebind<SubscribedType, Alloc>;
+  using SubscribedTypeAllocator = typename SubscribedTypeAllocatorTraits::allocator_type;
+  using SubscribedTypeDeleter = allocator::Deleter<SubscribedTypeAllocator, SubscribedType>;
+
+  using ROSMessageTypeAllocatorTraits = allocator::AllocRebind<ROSMessageType, Alloc>;
+  using ROSMessageTypeAllocator = typename ROSMessageTypeAllocatorTraits::allocator_type;
+  using ROSMessageTypeDeleter = allocator::Deleter<ROSMessageTypeAllocator, ROSMessageType>;
+
+  using ConstMessageSharedPtr = std::shared_ptr<const ROSMessageType>;
+  using MessageUniquePtr = std::unique_ptr<ROSMessageType, ROSMessageTypeDeleter>;
+
+  using ConstDataSharedPtr = std::shared_ptr<const SubscribedType>;
+  using SubscribedTypeUniquePtr = std::unique_ptr<SubscribedType, SubscribedTypeDeleter>;
 
   using BufferUniquePtr = typename rclcpp::experimental::buffers::IntraProcessBuffer<
-    MessageT,
+    SubscribedType,
     Alloc,
-    Deleter
+    SubscribedTypeDeleter
     >::UniquePtr;
 
   SubscriptionIntraProcessBuffer(
@@ -67,74 +78,101 @@ public:
     const std::string & topic_name,
     const rclcpp::QoS & qos_profile,
     rclcpp::IntraProcessBufferType buffer_type)
-  : SubscriptionIntraProcessBase(topic_name, qos_profile)
+  : SubscriptionROSMsgIntraProcessBuffer<ROSMessageType, ROSMessageTypeAllocator,
+      ROSMessageTypeDeleter>(
+      context, topic_name, qos_profile),
+    subscribed_type_allocator_(*allocator)
   {
+    allocator::set_allocator_for_deleter(&subscribed_type_deleter_, &subscribed_type_allocator_);
+
     // Create the intra-process buffer.
-    buffer_ = rclcpp::experimental::create_intra_process_buffer<MessageT, Alloc, Deleter>(
+    buffer_ = rclcpp::experimental::create_intra_process_buffer<SubscribedType, Alloc,
+        SubscribedTypeDeleter>(
       buffer_type,
       qos_profile,
-      allocator);
-
-    // Create the guard condition.
-    rcl_guard_condition_options_t guard_condition_options =
-      rcl_guard_condition_get_default_options();
-
-    gc_ = rcl_get_zero_initialized_guard_condition();
-    rcl_ret_t ret = rcl_guard_condition_init(
-      &gc_, context->get_rcl_context().get(), guard_condition_options);
-
-    if (RCL_RET_OK != ret) {
-      throw std::runtime_error(
-              "SubscriptionIntraProcessBuffer init error initializing guard condition");
-    }
-  }
-
-  virtual ~SubscriptionIntraProcessBuffer()
-  {
-    if (rcl_guard_condition_fini(&gc_) != RCL_RET_OK) {
-      RCUTILS_LOG_ERROR_NAMED(
-        "rclcpp",
-        "Failed to destroy guard condition: %s",
-        rcutils_get_error_string().str);
-    }
+      std::make_shared<Alloc>(subscribed_type_allocator_));
   }
 
   bool
-  is_ready(rcl_wait_set_t * wait_set)
+  is_ready(rcl_wait_set_t * wait_set) override
   {
     (void) wait_set;
     return buffer_->has_data();
   }
 
+  SubscribedTypeUniquePtr
+  convert_ros_message_to_subscribed_type_unique_ptr(const ROSMessageType & msg)
+  {
+    if constexpr (!std::is_same<SubscribedType, ROSMessageType>::value) {
+      auto ptr = SubscribedTypeAllocatorTraits::allocate(subscribed_type_allocator_, 1);
+      SubscribedTypeAllocatorTraits::construct(subscribed_type_allocator_, ptr);
+      rclcpp::TypeAdapter<SubscribedType, ROSMessageType>::convert_to_custom(msg, *ptr);
+      return SubscribedTypeUniquePtr(ptr, subscribed_type_deleter_);
+    } else {
+      throw std::runtime_error(
+              "convert_ros_message_to_subscribed_type_unique_ptr "
+              "unexpectedly called without TypeAdapter");
+    }
+  }
+
   void
-  provide_intra_process_message(ConstMessageSharedPtr message)
+  provide_intra_process_message(ConstMessageSharedPtr message) override
+  {
+    if constexpr (std::is_same<SubscribedType, ROSMessageType>::value) {
+      buffer_->add_shared(std::move(message));
+      trigger_guard_condition();
+    } else {
+      buffer_->add_shared(convert_ros_message_to_subscribed_type_unique_ptr(*message));
+      trigger_guard_condition();
+    }
+    this->invoke_on_new_message();
+  }
+
+  void
+  provide_intra_process_message(MessageUniquePtr message) override
+  {
+    if constexpr (std::is_same<SubscribedType, ROSMessageType>::value) {
+      buffer_->add_unique(std::move(message));
+      trigger_guard_condition();
+    } else {
+      buffer_->add_unique(convert_ros_message_to_subscribed_type_unique_ptr(*message));
+      trigger_guard_condition();
+    }
+    this->invoke_on_new_message();
+  }
+
+  void
+  provide_intra_process_data(ConstDataSharedPtr message)
   {
     buffer_->add_shared(std::move(message));
     trigger_guard_condition();
+    this->invoke_on_new_message();
   }
 
   void
-  provide_intra_process_message(MessageUniquePtr message)
+  provide_intra_process_data(SubscribedTypeUniquePtr message)
   {
     buffer_->add_unique(std::move(message));
     trigger_guard_condition();
+    this->invoke_on_new_message();
   }
 
   bool
-  use_take_shared_method() const
+  use_take_shared_method() const override
   {
     return buffer_->use_take_shared_method();
   }
 
 protected:
   void
-  trigger_guard_condition()
+  trigger_guard_condition() override
   {
-    rcl_ret_t ret = rcl_trigger_guard_condition(&gc_);
-    (void)ret;
+    this->gc_.trigger();
   }
 
   BufferUniquePtr buffer_;
+  SubscribedTypeAllocator subscribed_type_allocator_;
+  SubscribedTypeDeleter subscribed_type_deleter_;
 };
 
 }  // namespace experimental

rclcpp/include/rclcpp/function_traits.hpp

@@ -80,10 +80,12 @@ struct function_traits<ReturnTypeT (*)(Args ...)>: function_traits<ReturnTypeT(A
 
 // std::bind for object methods
 template<typename ClassT, typename ReturnTypeT, typename ... Args, typename ... FArgs>
-#if defined _LIBCPP_VERSION  // libc++ (Clang)
+#if defined DOXYGEN_ONLY
+struct function_traits<std::bind<ReturnTypeT (ClassT::*)(Args ...), FArgs ...>>
+#elif defined _LIBCPP_VERSION  // libc++ (Clang)
 struct function_traits<std::__bind<ReturnTypeT (ClassT::*)(Args ...), FArgs ...>>
 #elif defined _GLIBCXX_RELEASE  // glibc++ (GNU C++ >= 7.1)
-struct function_traits<std::_Bind<ReturnTypeT(ClassT::*(FArgs ...))(Args ...)>>
+struct function_traits<std::_Bind<ReturnTypeT(ClassT::* (FArgs ...))(Args ...)>>
 #elif defined __GLIBCXX__  // glibc++ (GNU C++)
 struct function_traits<std::_Bind<std::_Mem_fn<ReturnTypeT (ClassT::*)(Args ...)>(FArgs ...)>>
 #elif defined _MSC_VER  // MS Visual Studio
@@ -97,10 +99,12 @@ struct function_traits<
 
 // std::bind for object const methods
 template<typename ClassT, typename ReturnTypeT, typename ... Args, typename ... FArgs>
-#if defined _LIBCPP_VERSION  // libc++ (Clang)
+#if defined DOXYGEN_ONLY
+struct function_traits<std::bind<ReturnTypeT (ClassT::*)(Args ...) const, FArgs ...>>
+#elif defined _LIBCPP_VERSION  // libc++ (Clang)
 struct function_traits<std::__bind<ReturnTypeT (ClassT::*)(Args ...) const, FArgs ...>>
 #elif defined _GLIBCXX_RELEASE  // glibc++ (GNU C++ >= 7.1)
-struct function_traits<std::_Bind<ReturnTypeT(ClassT::*(FArgs ...))(Args ...) const>>
+struct function_traits<std::_Bind<ReturnTypeT(ClassT::* (FArgs ...))(Args ...) const>>
 #elif defined __GLIBCXX__  // glibc++ (GNU C++)
 struct function_traits<std::_Bind<std::_Mem_fn<ReturnTypeT (ClassT::*)(Args ...) const>(FArgs ...)>>
 #elif defined _MSC_VER  // MS Visual Studio
@@ -114,7 +118,9 @@ struct function_traits<
 
 // std::bind for free functions
 template<typename ReturnTypeT, typename ... Args, typename ... FArgs>
-#if defined _LIBCPP_VERSION  // libc++ (Clang)
+#if defined DOXYGEN_ONLY
+struct function_traits<std::bind<ReturnTypeT( &)(Args ...), FArgs ...>>
+#elif defined _LIBCPP_VERSION  // libc++ (Clang)
 struct function_traits<std::__bind<ReturnTypeT( &)(Args ...), FArgs ...>>
 #elif defined __GLIBCXX__  // glibc++ (GNU C++)
 struct function_traits<std::_Bind<ReturnTypeT(*(FArgs ...))(Args ...)>>

rclcpp/include/rclcpp/generic_publisher.hpp

@@ -31,6 +31,8 @@
 #include "rclcpp/typesupport_helpers.hpp"
 #include "rclcpp/visibility_control.hpp"
 
+#include "rmw/rmw.h"
+
 namespace rclcpp
 {
 
@@ -60,7 +62,6 @@ public:
    * \param topic_name Topic name
    * \param topic_type Topic type
    * \param qos %QoS settings
-   * \param callback Callback for new messages of serialized form
    * \param options %Publisher options.
    * Not all publisher options are currently respected, the only relevant options for this
    * publisher are `event_callbacks`, `use_default_callbacks`, and `%callback_group`.
@@ -117,9 +118,24 @@ public:
   RCLCPP_PUBLIC
   void publish(const rclcpp::SerializedMessage & message);
 
+  /**
+   * Publish a rclcpp::SerializedMessage via loaned message after de-serialization.
+   *
+   * \param message a serialized message
+   * \throws anything rclcpp::exceptions::throw_from_rcl_error can show
+   */
+  RCLCPP_PUBLIC
+  void publish_as_loaned_msg(const rclcpp::SerializedMessage & message);
+
 private:
   // The type support library should stay loaded, so it is stored in the GenericPublisher
   std::shared_ptr<rcpputils::SharedLibrary> ts_lib_;
+
+  void * borrow_loaned_message();
+  void deserialize_message(
+    const rmw_serialized_message_t & serialized_message,
+    void * deserialized_msg);
+  void publish_loaned_message(void * loaned_message);
 };
 
 }  // namespace rclcpp

rclcpp/include/rclcpp/get_message_type_support_handle.hpp

@@ -28,7 +28,17 @@
 namespace rclcpp
 {
 
-/// Specialization for when MessageT is an actual ROS message type.
+#ifdef DOXYGEN_ONLY
+
+/// Returns the message type support for the given `MessageT` type.
+/**
+ * \tparam MessageT an actual ROS message type or an adapted type using `rclcpp::TypeAdapter`
+ */
+template<typename MessageT>
+constexpr const rosidl_message_type_support_t & get_message_type_support_handle();
+
+#else
+
 template<typename MessageT>
 constexpr
 typename std::enable_if_t<
@@ -44,7 +54,6 @@ get_message_type_support_handle()
   return *handle;
 }
 
-/// Specialization for when MessageT is an adapted type using rclcpp::TypeAdapter.
 template<typename AdaptedType>
 constexpr
 typename std::enable_if_t<
@@ -63,12 +72,9 @@ get_message_type_support_handle()
   return *handle;
 }
 
-/// Specialization for when MessageT is not a ROS message nor an adapted type.
-/**
- * This specialization is a pass through runtime check, which allows a better
- * static_assert to catch this issue further down the line.
- * This should never get to be called in practice, and is purely defensive.
- */
+// This specialization is a pass through runtime check, which allows a better
+// static_assert to catch this issue further down the line.
+// This should never get to be called in practice, and is purely defensive.
 template<
   typename AdaptedType
 >
@@ -85,6 +91,8 @@ get_message_type_support_handle()
           "should never be called");
 }
 
+#endif
+
 }  // namespace rclcpp
 
 #endif  // RCLCPP__GET_MESSAGE_TYPE_SUPPORT_HANDLE_HPP_

rclcpp/include/rclcpp/graph_listener.hpp

@@ -24,6 +24,7 @@
 #include "rcl/guard_condition.h"
 #include "rcl/wait.h"
 #include "rclcpp/context.hpp"
+#include "rclcpp/guard_condition.hpp"
 #include "rclcpp/macros.hpp"
 #include "rclcpp/node_interfaces/node_graph_interface.hpp"
 #include "rclcpp/visibility_control.hpp"
@@ -187,7 +188,7 @@ private:
   mutable std::mutex node_graph_interfaces_mutex_;
   std::vector<rclcpp::node_interfaces::NodeGraphInterface *> node_graph_interfaces_;
 
-  rcl_guard_condition_t interrupt_guard_condition_ = rcl_get_zero_initialized_guard_condition();
+  rclcpp::GuardCondition interrupt_guard_condition_;
   rcl_wait_set_t wait_set_ = rcl_get_zero_initialized_wait_set();
 };
 

rclcpp/include/rclcpp/guard_condition.hpp

@@ -40,6 +40,8 @@ public:
    *   Defaults to using the global default context singleton.
    *   Shared ownership of the context is held with the guard condition until
    *   destruction.
+   * \param[in] guard_condition_options Optional guard condition options to be used.
+   *   Defaults to using the default guard condition options.
    * \throws std::invalid_argument if the context is nullptr.
    * \throws rclcpp::exceptions::RCLError based exceptions when underlying
    *   rcl functions fail.
@@ -47,7 +49,9 @@ public:
   RCLCPP_PUBLIC
   explicit GuardCondition(
     rclcpp::Context::SharedPtr context =
-    rclcpp::contexts::get_global_default_context());
+    rclcpp::contexts::get_global_default_context(),
+    rcl_guard_condition_options_t guard_condition_options =
+    rcl_guard_condition_get_default_options());
 
   RCLCPP_PUBLIC
   virtual
@@ -58,6 +62,11 @@ public:
   rclcpp::Context::SharedPtr
   get_context() const;
 
+  /// Return the underlying rcl guard condition structure.
+  RCLCPP_PUBLIC
+  rcl_guard_condition_t &
+  get_rcl_guard_condition();
+
   /// Return the underlying rcl guard condition structure.
   RCLCPP_PUBLIC
   const rcl_guard_condition_t &
@@ -89,10 +98,27 @@ public:
   bool
   exchange_in_use_by_wait_set_state(bool in_use_state);
 
+  /// Adds the guard condition to a waitset
+  /**
+   * This function is thread-safe.
+   * \param[in] wait_set pointer to a wait set where to add the guard condition
+   */
+  RCLCPP_PUBLIC
+  void
+  add_to_wait_set(rcl_wait_set_t * wait_set);
+
+  RCLCPP_PUBLIC
+  void
+  set_on_trigger_callback(std::function<void(size_t)> callback);
+
 protected:
   rclcpp::Context::SharedPtr context_;
   rcl_guard_condition_t rcl_guard_condition_;
   std::atomic<bool> in_use_by_wait_set_{false};
+  std::recursive_mutex reentrant_mutex_;
+  std::function<void(size_t)> on_trigger_callback_{nullptr};
+  size_t unread_count_{0};
+  rcl_wait_set_t * wait_set_{nullptr};
 };
 
 }  // namespace rclcpp

rclcpp/include/rclcpp/init_options.hpp

@@ -29,7 +29,7 @@ class InitOptions
 {
 public:
   /// If true, the context will be shutdown on SIGINT by the signal handler (if it was installed).
-  bool shutdown_on_sigint = true;
+  bool shutdown_on_signal = true;
 
   /// Constructor
   /**

rclcpp/include/rclcpp/loaned_message.hpp

@@ -117,7 +117,9 @@ public:
   : pub_(std::move(other.pub_)),
     message_(std::move(other.message_)),
     message_allocator_(std::move(other.message_allocator_))
-  {}
+  {
+    other.message_ = nullptr;
+  }
 
   /// Destructor of the LoanedMessage class.
   /**

rclcpp/include/rclcpp/logger.hpp

@@ -79,7 +79,7 @@ get_node_logger(const rcl_node_t * node);
 /// Get the current logging directory.
 /**
  * For more details of how the logging directory is determined,
- * see \ref rcl_logging_get_logging_directory.
+ * see rcl_logging_get_logging_directory().
  *
  * \returns the logging directory being used.
  * \throws rclcpp::exceptions::RCLError if an unexpected error occurs.

rclcpp/include/rclcpp/memory_strategy.hpp

@@ -64,9 +64,11 @@ public:
   virtual void clear_handles() = 0;
   virtual void remove_null_handles(rcl_wait_set_t * wait_set) = 0;
 
-  virtual void add_guard_condition(const rcl_guard_condition_t * guard_condition) = 0;
+  virtual void
+  add_guard_condition(const rclcpp::GuardCondition & guard_condition) = 0;
 
-  virtual void remove_guard_condition(const rcl_guard_condition_t * guard_condition) = 0;
+  virtual void
+  remove_guard_condition(const rclcpp::GuardCondition * guard_condition) = 0;
 
   virtual void
   get_next_subscription(
@@ -98,52 +100,52 @@ public:
 
   static rclcpp::SubscriptionBase::SharedPtr
   get_subscription_by_handle(
-    std::shared_ptr<const rcl_subscription_t> subscriber_handle,
+    const std::shared_ptr<const rcl_subscription_t> & subscriber_handle,
     const WeakCallbackGroupsToNodesMap & weak_groups_to_nodes);
 
   static rclcpp::ServiceBase::SharedPtr
   get_service_by_handle(
-    std::shared_ptr<const rcl_service_t> service_handle,
+    const std::shared_ptr<const rcl_service_t> & service_handle,
     const WeakCallbackGroupsToNodesMap & weak_groups_to_nodes);
 
   static rclcpp::ClientBase::SharedPtr
   get_client_by_handle(
-    std::shared_ptr<const rcl_client_t> client_handle,
+    const std::shared_ptr<const rcl_client_t> & client_handle,
     const WeakCallbackGroupsToNodesMap & weak_groups_to_nodes);
 
   static rclcpp::TimerBase::SharedPtr
   get_timer_by_handle(
-    std::shared_ptr<const rcl_timer_t> timer_handle,
+    const std::shared_ptr<const rcl_timer_t> & timer_handle,
     const WeakCallbackGroupsToNodesMap & weak_groups_to_nodes);
 
   static rclcpp::node_interfaces::NodeBaseInterface::SharedPtr
   get_node_by_group(
-    rclcpp::CallbackGroup::SharedPtr group,
+    const rclcpp::CallbackGroup::SharedPtr & group,
     const WeakCallbackGroupsToNodesMap & weak_groups_to_nodes);
 
   static rclcpp::CallbackGroup::SharedPtr
   get_group_by_subscription(
-    rclcpp::SubscriptionBase::SharedPtr subscription,
+    const rclcpp::SubscriptionBase::SharedPtr & subscription,
     const WeakCallbackGroupsToNodesMap & weak_groups_to_nodes);
 
   static rclcpp::CallbackGroup::SharedPtr
   get_group_by_service(
-    rclcpp::ServiceBase::SharedPtr service,
+    const rclcpp::ServiceBase::SharedPtr & service,
     const WeakCallbackGroupsToNodesMap & weak_groups_to_nodes);
 
   static rclcpp::CallbackGroup::SharedPtr
   get_group_by_client(
-    rclcpp::ClientBase::SharedPtr client,
+    const rclcpp::ClientBase::SharedPtr & client,
     const WeakCallbackGroupsToNodesMap & weak_groups_to_nodes);
 
   static rclcpp::CallbackGroup::SharedPtr
   get_group_by_timer(
-    rclcpp::TimerBase::SharedPtr timer,
+    const rclcpp::TimerBase::SharedPtr & timer,
     const WeakCallbackGroupsToNodesMap & weak_groups_to_nodes);
 
   static rclcpp::CallbackGroup::SharedPtr
   get_group_by_waitable(
-    rclcpp::Waitable::SharedPtr waitable,
+    const rclcpp::Waitable::SharedPtr & waitable,
     const WeakCallbackGroupsToNodesMap & weak_groups_to_nodes);
 };
 

rclcpp/include/rclcpp/message_memory_strategy.hpp

@@ -18,6 +18,7 @@
 #include <memory>
 #include <stdexcept>
 
+#include "rcl/allocator.h"
 #include "rcl/types.h"
 
 #include "rclcpp/allocator/allocator_common.hpp"
@@ -61,7 +62,12 @@ public:
     message_allocator_ = std::make_shared<MessageAlloc>();
     serialized_message_allocator_ = std::make_shared<SerializedMessageAlloc>();
     buffer_allocator_ = std::make_shared<BufferAlloc>();
-    rcutils_allocator_ = allocator::get_rcl_allocator<char, BufferAlloc>(*buffer_allocator_.get());
+    if constexpr (std::is_same_v<Alloc, std::allocator<void>>) {
+      rcutils_allocator_ = rcl_get_default_allocator();
+    } else {
+      rcutils_allocator_ = allocator::get_rcl_allocator<char,
+          BufferAlloc>(*buffer_allocator_.get());
+    }
   }
 
   explicit MessageMemoryStrategy(std::shared_ptr<Alloc> allocator)
@@ -69,7 +75,12 @@ public:
     message_allocator_ = std::make_shared<MessageAlloc>(*allocator.get());
     serialized_message_allocator_ = std::make_shared<SerializedMessageAlloc>(*allocator.get());
     buffer_allocator_ = std::make_shared<BufferAlloc>(*allocator.get());
-    rcutils_allocator_ = allocator::get_rcl_allocator<char, BufferAlloc>(*buffer_allocator_.get());
+    if constexpr (std::is_same_v<Alloc, std::allocator<void>>) {
+      rcutils_allocator_ = rcl_get_default_allocator();
+    } else {
+      rcutils_allocator_ = allocator::get_rcl_allocator<char,
+          BufferAlloc>(*buffer_allocator_.get());
+    }
   }
 
   virtual ~MessageMemoryStrategy() = default;

rclcpp/include/rclcpp/node.hpp

@@ -148,10 +148,16 @@ public:
     rclcpp::CallbackGroupType group_type,
     bool automatically_add_to_executor_with_node = true);
 
-  /// Return the list of callback groups in the node.
+  /// Iterate over the callback groups in the node, calling the given function on each valid one.
+  /**
+   * This method is called in a thread-safe way, and also makes sure to only call the given
+   * function on those items that are still valid.
+   *
+   * \param[in] func The callback function to call on each valid callback group.
+   */
   RCLCPP_PUBLIC
-  const std::vector<rclcpp::CallbackGroup::WeakPtr> &
-  get_callback_groups() const;
+  void
+  for_each_callback_group(const node_interfaces::NodeBaseInterface::CallbackGroupFunction & func);
 
   /// Create and return a Publisher.
   /**
@@ -389,22 +395,6 @@ public:
     rcl_interfaces::msg::ParameterDescriptor{},
     bool ignore_override = false);
 
-  /// Declare a parameter
-  [[deprecated(
-    "declare_parameter() with only a name is deprecated and will be deleted in the future.\n" \
-    "If you want to declare a parameter that won't change type without a default value use:\n" \
-    "`node->declare_parameter<ParameterT>(name)`, where e.g. ParameterT=int64_t.\n\n" \
-    "If you want to declare a parameter that can dynamically change type use:\n" \
-    "```\n" \
-    "rcl_interfaces::msg::ParameterDescriptor descriptor;\n" \
-    "descriptor.dynamic_typing = true;\n" \
-    "node->declare_parameter(name, rclcpp::ParameterValue{}, descriptor);\n" \
-    "```"
-  )]]
-  RCLCPP_PUBLIC
-  const rclcpp::ParameterValue &
-  declare_parameter(const std::string & name);
-
   /// Declare and initialize a parameter with a type.
   /**
    * See the non-templated declare_parameter() on this class for details.
@@ -714,6 +704,24 @@ public:
     ParameterT & parameter,
     const ParameterT & alternative_value) const;
 
+  /// Return the parameter value, or the "alternative_value" if not set.
+  /**
+   * If the parameter was not set, then the "alternative_value" argument is returned.
+   *
+   * This method will not throw the rclcpp::exceptions::ParameterNotDeclaredException exception.
+   *
+   * In all cases, the parameter is never set or declared within the node.
+   *
+   * \param[in] name The name of the parameter to get.
+   * \param[in] alternative_value Value to be stored in output if the parameter was not set.
+   * \returns The value of the parameter.
+   */
+  template<typename ParameterT>
+  ParameterT
+  get_parameter_or(
+    const std::string & name,
+    const ParameterT & alternative_value) const;
+
   /// Return the parameters by the given parameter names.
   /**
    * Like get_parameters(), this method may throw the
@@ -979,12 +987,15 @@ public:
   std::map<std::string, std::vector<std::string>>
   get_service_names_and_types() const;
 
-  /// Return the number of publishers that are advertised on a given topic.
+  /// Return a map of existing service names to list of service types for a specific node.
   /**
-   * \param[in] node_name the node_name on which to count the publishers.
-   * \param[in] namespace_ the namespace of the node associated with the name
-   * \return number of publishers that are advertised on a given topic.
-   * \throws std::runtime_error if publishers could not be counted
+   * 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>>

rclcpp/include/rclcpp/node_impl.hpp

@@ -220,12 +220,16 @@ Node::declare_parameter(
   // get advantage of parameter value template magic to get
   // the correct rclcpp::ParameterType from ParameterT
   rclcpp::ParameterValue value{ParameterT{}};
-  return this->declare_parameter(
-    name,
-    value.get_type(),
-    parameter_descriptor,
-    ignore_override
-  ).get<ParameterT>();
+  try {
+    return this->declare_parameter(
+      name,
+      value.get_type(),
+      parameter_descriptor,
+      ignore_override
+    ).get<ParameterT>();
+  } catch (const ParameterTypeException &) {
+    throw exceptions::UninitializedStaticallyTypedParameterException(name);
+  }
 }
 
 template<typename ParameterT>
@@ -309,6 +313,17 @@ Node::get_parameter_or(
   return got_parameter;
 }
 
+template<typename ParameterT>
+ParameterT
+Node::get_parameter_or(
+  const std::string & name,
+  const ParameterT & alternative_value) const
+{
+  ParameterT parameter;
+  get_parameter_or(name, parameter, alternative_value);
+  return parameter;
+}
+
 // this is a partially-specialized version of get_parameter above,
 // where our concrete type for ParameterT is std::map, but the to-be-determined
 // type is the value in the map.

rclcpp/include/rclcpp/node_interfaces/detail/node_interfaces_helpers.hpp

@@ -0,0 +1,210 @@
+// Copyright 2022 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__DETAIL__NODE_INTERFACES_HELPERS_HPP_
+#define RCLCPP__NODE_INTERFACES__DETAIL__NODE_INTERFACES_HELPERS_HPP_
+
+#include <memory>
+#include <tuple>
+#include <type_traits>
+#include <utility>
+
+#include "rclcpp/visibility_control.hpp"
+
+namespace rclcpp
+{
+namespace node_interfaces
+{
+namespace detail
+{
+
+// Support and Helper template classes for the NodeInterfaces class.
+
+template<typename NodeT, typename ... Ts>
+std::tuple<std::shared_ptr<Ts>...>
+init_tuple(NodeT & n);
+
+/// Stores the interfaces in a tuple, provides constructors, and getters.
+template<typename ... InterfaceTs>
+struct NodeInterfacesStorage
+{
+  template<typename NodeT>
+  NodeInterfacesStorage(NodeT & node)  // NOLINT(runtime/explicit)
+  : interfaces_(init_tuple<decltype(node), InterfaceTs ...>(node))
+  {}
+
+  explicit NodeInterfacesStorage(std::shared_ptr<InterfaceTs>... args)
+  : interfaces_(args ...)
+  {}
+
+  /// Individual Node Interface non-const getter.
+  template<typename NodeInterfaceT>
+  std::shared_ptr<NodeInterfaceT>
+  get()
+  {
+    static_assert(
+      (std::is_same_v<NodeInterfaceT, InterfaceTs>|| ...),
+      "NodeInterfaces class does not contain given NodeInterfaceT");
+    return std::get<std::shared_ptr<NodeInterfaceT>>(interfaces_);
+  }
+
+  /// Individual Node Interface const getter.
+  template<typename NodeInterfaceT>
+  std::shared_ptr<const NodeInterfaceT>
+  get() const
+  {
+    static_assert(
+      (std::is_same_v<NodeInterfaceT, InterfaceTs>|| ...),
+      "NodeInterfaces class does not contain given NodeInterfaceT");
+    return std::get<std::shared_ptr<NodeInterfaceT>>(interfaces_);
+  }
+
+protected:
+  std::tuple<std::shared_ptr<InterfaceTs>...> interfaces_;
+};
+
+/// Prototype of NodeInterfacesSupports.
+/**
+ * Should read NodeInterfacesSupports<..., T, ...> as "NodeInterfaces supports T", and
+ * if NodeInterfacesSupport is specialized for T, the is_supported should be
+ * set to std::true_type, but by default it is std::false_type, which will
+ * lead to a compiler error when trying to use T with NodeInterfaces.
+ */
+template<typename StorageClassT, typename ... Ts>
+struct NodeInterfacesSupports;
+
+/// Prototype of NodeInterfacesSupportCheck template meta-function.
+/**
+ * This meta-function checks that all the types given are supported,
+ * throwing a more human-readable error if an unsupported type is used.
+ */
+template<typename StorageClassT, typename ... InterfaceTs>
+struct NodeInterfacesSupportCheck;
+
+/// Iterating specialization that ensures classes are supported and inherited.
+template<typename StorageClassT, typename NextInterfaceT, typename ... RemainingInterfaceTs>
+struct NodeInterfacesSupportCheck<StorageClassT, NextInterfaceT, RemainingInterfaceTs ...>
+  : public NodeInterfacesSupportCheck<StorageClassT, RemainingInterfaceTs ...>
+{
+  static_assert(
+    NodeInterfacesSupports<StorageClassT, NextInterfaceT>::is_supported::value,
+    "given NodeInterfaceT is not supported by rclcpp::node_interfaces::NodeInterfaces");
+};
+
+/// Terminating case when there are no more "RemainingInterfaceTs".
+template<typename StorageClassT>
+struct NodeInterfacesSupportCheck<StorageClassT>
+{};
+
+/// Default specialization, needs to be specialized for each supported interface.
+template<typename StorageClassT, typename ... RemainingInterfaceTs>
+struct NodeInterfacesSupports
+{
+  // Specializations need to set this to std::true_type in addition to other interfaces.
+  using is_supported = std::false_type;
+};
+
+/// Terminating specialization of NodeInterfacesSupports.
+template<typename StorageClassT>
+struct NodeInterfacesSupports<StorageClassT>
+  : public StorageClassT
+{
+  /// Perfect forwarding constructor to get arguments down to StorageClassT.
+  template<typename ... ArgsT>
+  explicit NodeInterfacesSupports(ArgsT && ... args)
+  : StorageClassT(std::forward<ArgsT>(args) ...)
+  {}
+};
+
+// Helper functions to initialize the tuple in NodeInterfaces.
+
+template<typename StorageClassT, typename ElementT, typename TupleT, typename NodeT>
+void
+init_element(TupleT & t, NodeT & n)
+{
+  std::get<std::shared_ptr<ElementT>>(t) =
+    NodeInterfacesSupports<StorageClassT, ElementT>::get_from_node_like(n);
+}
+
+template<typename NodeT, typename ... Ts>
+std::tuple<std::shared_ptr<Ts>...>
+init_tuple(NodeT & n)
+{
+  using StorageClassT = NodeInterfacesStorage<Ts ...>;
+  std::tuple<std::shared_ptr<Ts>...> t;
+  (init_element<StorageClassT, Ts>(t, n), ...);
+  return t;
+}
+
+/// Macro for creating specializations with less boilerplate.
+/**
+ * You can use this macro to add support for your interface class if:
+ *
+ * - The standard getter is get_node_{NodeInterfaceName}_interface(), and
+ * - the getter returns a non-const shared_ptr<{NodeInterfaceType}>
+ *
+ * Examples of using this can be seen in the standard node interface headers
+ * in rclcpp, e.g. rclcpp/node_interfaces/node_base_interface.hpp has:
+ *
+ *   RCLCPP_NODE_INTERFACE_HELPERS_SUPPORT(rclcpp::node_interfaces::NodeBaseInterface, base)
+ *
+ * If your interface has a non-standard getter, or you want to instrument it or
+ * something like that, then you'll need to create your own specialization of
+ * the NodeInterfacesSupports struct without this macro.
+ */
+#define RCLCPP_NODE_INTERFACE_HELPERS_SUPPORT(NodeInterfaceType, NodeInterfaceName) \
+  namespace rclcpp::node_interfaces::detail { \
+  template<typename StorageClassT, typename ... RemainingInterfaceTs> \
+  struct NodeInterfacesSupports< \
+    StorageClassT, \
+    NodeInterfaceType, \
+    RemainingInterfaceTs ...> \
+    : public NodeInterfacesSupports<StorageClassT, RemainingInterfaceTs ...> \
+  { \
+    using is_supported = std::true_type; \
+ \
+    template<typename NodeT> \
+    static \
+    std::shared_ptr<NodeInterfaceType> \
+    get_from_node_like(NodeT & node_like) \
+    { \
+      return node_like.get_node_ ## NodeInterfaceName ## _interface(); \
+    } \
+ \
+    /* Perfect forwarding constructor to get arguments down to StorageClassT (eventually). */ \
+    template<typename ... ArgsT> \
+    explicit NodeInterfacesSupports(ArgsT && ... args) \
+      : NodeInterfacesSupports<StorageClassT, RemainingInterfaceTs ...>( \
+        std::forward<ArgsT>(args) ...) \
+    {} \
+ \
+    std::shared_ptr<NodeInterfaceType> \
+    get_node_ ## NodeInterfaceName ## _interface() \
+    { \
+      return StorageClassT::template get<NodeInterfaceType>(); \
+    } \
+ \
+    std::shared_ptr<const NodeInterfaceType> \
+    get_node_ ## NodeInterfaceName ## _interface() const \
+    { \
+      return StorageClassT::template get<NodeInterfaceType>(); \
+    } \
+  }; \
+  }  // namespace rclcpp::node_interfaces::detail
+
+}  // namespace detail
+}  // namespace node_interfaces
+}  // namespace rclcpp
+
+#endif  // RCLCPP__NODE_INTERFACES__DETAIL__NODE_INTERFACES_HELPERS_HPP_

rclcpp/include/rclcpp/node_interfaces/node_base.hpp

@@ -15,11 +15,14 @@
 #ifndef RCLCPP__NODE_INTERFACES__NODE_BASE_HPP_
 #define RCLCPP__NODE_INTERFACES__NODE_BASE_HPP_
 
+#include <functional>
 #include <memory>
+#include <mutex>
 #include <string>
 #include <vector>
 
 #include "rcl/node.h"
+#include "rclcpp/callback_group.hpp"
 #include "rclcpp/context.hpp"
 #include "rclcpp/macros.hpp"
 #include "rclcpp/node_interfaces/node_base_interface.hpp"
@@ -31,7 +34,7 @@ namespace node_interfaces
 {
 
 /// Implementation of the NodeBase part of the Node API.
-class NodeBase : public NodeBaseInterface
+class NodeBase : public NodeBaseInterface, public std::enable_shared_from_this<NodeBase>
 {
 public:
   RCLCPP_SMART_PTR_ALIASES_ONLY(NodeBase)
@@ -95,22 +98,25 @@ public:
   bool
   callback_group_in_node(rclcpp::CallbackGroup::SharedPtr group) override;
 
+  /// Iterate over the stored callback groups, calling the given function on each valid one.
+  /**
+   * This method is called in a thread-safe way, and also makes sure to only call the given
+   * function on those items that are still valid.
+   *
+   * \param[in] func The callback function to call on each valid callback group.
+   */
   RCLCPP_PUBLIC
-  const std::vector<rclcpp::CallbackGroup::WeakPtr> &
-  get_callback_groups() const override;
+  void
+  for_each_callback_group(const CallbackGroupFunction & func) override;
 
   RCLCPP_PUBLIC
   std::atomic_bool &
   get_associated_with_executor_atomic() override;
 
   RCLCPP_PUBLIC
-  rcl_guard_condition_t *
+  rclcpp::GuardCondition &
   get_notify_guard_condition() override;
 
-  RCLCPP_PUBLIC
-  std::unique_lock<std::recursive_mutex>
-  acquire_notify_guard_condition_lock() const override;
-
   RCLCPP_PUBLIC
   bool
   get_use_intra_process_default() const override;
@@ -132,13 +138,14 @@ private:
   std::shared_ptr<rcl_node_t> node_handle_;
 
   rclcpp::CallbackGroup::SharedPtr default_callback_group_;
+  std::mutex callback_groups_mutex_;
   std::vector<rclcpp::CallbackGroup::WeakPtr> callback_groups_;
 
   std::atomic_bool associated_with_executor_;
 
   /// Guard condition for notifying the Executor of changes to this node.
   mutable std::recursive_mutex notify_guard_condition_mutex_;
-  rcl_guard_condition_t notify_guard_condition_ = rcl_get_zero_initialized_guard_condition();
+  rclcpp::GuardCondition notify_guard_condition_;
   bool notify_guard_condition_is_valid_;
 };
 

rclcpp/include/rclcpp/node_interfaces/node_base_interface.hpp

@@ -24,7 +24,9 @@
 
 #include "rclcpp/callback_group.hpp"
 #include "rclcpp/context.hpp"
+#include "rclcpp/guard_condition.hpp"
 #include "rclcpp/macros.hpp"
+#include "rclcpp/node_interfaces/detail/node_interfaces_helpers.hpp"
 #include "rclcpp/visibility_control.hpp"
 
 namespace rclcpp
@@ -122,11 +124,19 @@ public:
   bool
   callback_group_in_node(rclcpp::CallbackGroup::SharedPtr group) = 0;
 
-  /// Return list of callback groups associated with this node.
+  using CallbackGroupFunction = std::function<void (rclcpp::CallbackGroup::SharedPtr)>;
+
+  /// Iterate over the stored callback groups, calling the given function on each valid one.
+  /**
+   * This method is called in a thread-safe way, and also makes sure to only call the given
+   * function on those items that are still valid.
+   *
+   * \param[in] func The callback function to call on each valid callback group.
+   */
   RCLCPP_PUBLIC
   virtual
-  const std::vector<rclcpp::CallbackGroup::WeakPtr> &
-  get_callback_groups() const = 0;
+  void
+  for_each_callback_group(const CallbackGroupFunction & func) = 0;
 
   /// Return the atomic bool which is used to ensure only one executor is used.
   RCLCPP_PUBLIC
@@ -134,24 +144,17 @@ public:
   std::atomic_bool &
   get_associated_with_executor_atomic() = 0;
 
-  /// Return guard condition that should be notified when the internal node state changes.
+  /// Return a guard condition that should be notified when the internal node state changes.
   /**
    * For example, this should be notified when a publisher is added or removed.
    *
-   * \return the rcl_guard_condition_t if it is valid, else nullptr
+   * \return the GuardCondition if it is valid, else thow runtime error
    */
   RCLCPP_PUBLIC
   virtual
-  rcl_guard_condition_t *
+  rclcpp::GuardCondition &
   get_notify_guard_condition() = 0;
 
-  /// Acquire and return a scoped lock that protects the notify guard condition.
-  /** This should be used when triggering the notify guard condition. */
-  RCLCPP_PUBLIC
-  virtual
-  std::unique_lock<std::recursive_mutex>
-  acquire_notify_guard_condition_lock() const = 0;
-
   /// Return the default preference for using intra process communication.
   RCLCPP_PUBLIC
   virtual
@@ -175,4 +178,6 @@ public:
 }  // namespace node_interfaces
 }  // namespace rclcpp
 
+RCLCPP_NODE_INTERFACE_HELPERS_SUPPORT(rclcpp::node_interfaces::NodeBaseInterface, base)
+
 #endif  // RCLCPP__NODE_INTERFACES__NODE_BASE_INTERFACE_HPP_

rclcpp/include/rclcpp/node_interfaces/node_clock_interface.hpp

@@ -17,6 +17,7 @@
 
 #include "rclcpp/clock.hpp"
 #include "rclcpp/macros.hpp"
+#include "rclcpp/node_interfaces/detail/node_interfaces_helpers.hpp"
 #include "rclcpp/visibility_control.hpp"
 
 namespace rclcpp
@@ -50,4 +51,6 @@ public:
 }  // namespace node_interfaces
 }  // namespace rclcpp
 
+RCLCPP_NODE_INTERFACE_HELPERS_SUPPORT(rclcpp::node_interfaces::NodeClockInterface, clock)
+
 #endif  // RCLCPP__NODE_INTERFACES__NODE_CLOCK_INTERFACE_HPP_

rclcpp/include/rclcpp/node_interfaces/node_graph.hpp

@@ -20,6 +20,7 @@
 #include <memory>
 #include <mutex>
 #include <string>
+#include <tuple>
 #include <utility>
 #include <vector>
 
@@ -70,10 +71,34 @@ public:
     const std::string & node_name,
     const std::string & namespace_) const override;
 
+  RCLCPP_PUBLIC
+  std::map<std::string, std::vector<std::string>>
+  get_client_names_and_types_by_node(
+    const std::string & node_name,
+    const std::string & namespace_) const override;
+
+  RCLCPP_PUBLIC
+  std::map<std::string, std::vector<std::string>>
+  get_publisher_names_and_types_by_node(
+    const std::string & node_name,
+    const std::string & namespace_,
+    bool no_demangle = false) const override;
+
+  RCLCPP_PUBLIC
+  std::map<std::string, std::vector<std::string>>
+  get_subscriber_names_and_types_by_node(
+    const std::string & node_name,
+    const std::string & namespace_,
+    bool no_demangle = false) const override;
+
   RCLCPP_PUBLIC
   std::vector<std::string>
   get_node_names() const override;
 
+  RCLCPP_PUBLIC
+  std::vector<std::tuple<std::string, std::string, std::string>>
+  get_node_names_with_enclaves() const override;
+
   RCLCPP_PUBLIC
   std::vector<std::pair<std::string, std::string>>
   get_node_names_and_namespaces() const override;

rclcpp/include/rclcpp/node_interfaces/node_graph_interface.hpp

@@ -20,6 +20,7 @@
 #include <chrono>
 #include <map>
 #include <string>
+#include <tuple>
 #include <utility>
 #include <vector>
 
@@ -28,6 +29,7 @@
 
 #include "rclcpp/event.hpp"
 #include "rclcpp/macros.hpp"
+#include "rclcpp/node_interfaces/detail/node_interfaces_helpers.hpp"
 #include "rclcpp/qos.hpp"
 #include "rclcpp/visibility_control.hpp"
 
@@ -51,12 +53,16 @@ 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)),
+  : endpoint_type_(static_cast<rclcpp::EndpointType>(info.endpoint_type)),
     qos_profile_({info.qos_profile.history, info.qos_profile.depth}, info.qos_profile)
   {
+    if (!info.node_name || !info.node_namespace || !info.topic_type) {
+      throw std::invalid_argument("Constructor TopicEndpointInfo with invalid topic endpoint info");
+    }
+    node_name_ = info.node_name;
+    node_namespace_ = info.node_namespace;
+    topic_type_ = info.topic_type;
+
     std::copy(info.endpoint_gid, info.endpoint_gid + RMW_GID_STORAGE_SIZE, endpoint_gid_.begin());
   }
 
@@ -146,7 +152,9 @@ public:
   /**
    * A topic is considered to exist when at least one publisher or subscriber
    * exists for it, whether they be local or remote to this process.
-   * The returned names are the actual names used and do not have remap rules applied.
+   * The returned names are the actual names of the topics, either announced by another nodes or by this one.
+   * Attempting to create publishers or subscribers using names returned by this function may not
+   * result in the desired topic name being used depending on the remap rules in use.
    *
    * \param[in] no_demangle if true, topic names and types are not demangled
    */
@@ -160,7 +168,9 @@ public:
    * A service is considered to exist when at least one service server or
    * service client exists for it, whether they be local or remote to this
    * process.
-   * The returned names are the actual names used and do not have remap rules applied.
+   * The returned names are the actual names of the services, either announced by another nodes or by this one.
+   * Attempting to create clients or services using names returned by this function may not result in
+   * the desired service name being used depending on the remap rules in use.
    */
   RCLCPP_PUBLIC
   virtual
@@ -170,7 +180,9 @@ public:
   /// 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.
+   * The returned names are the actual names after remap rules applied.
+   * Attempting to create service clients using names returned by this function may not
+   * result in the desired service name being used depending on the remap rules in use.
    *
    * \param[in] node_name name of the node
    * \param[in] namespace_ namespace of the node
@@ -182,18 +194,85 @@ public:
     const std::string & node_name,
     const std::string & namespace_) const = 0;
 
+  /// Return a map of existing service names and types with a specific node.
+  /**
+   * This function only considers clients - not service servers.
+   * The returned names are the actual names after remap rules applied.
+   * Attempting to create service servers using names returned by this function may not
+   * result in the desired service name being used depending on the remap rules in use.
+   *
+   * \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_client_names_and_types_by_node(
+    const std::string & node_name,
+    const std::string & namespace_) const = 0;
+
+  /// Return a map of existing topic names to list of topic types for a specific node.
+  /**
+   * This function only considers publishers - not subscribers.
+   * The returned names are the actual names after remap rules applied.
+   * Attempting to create publishers or subscribers using names returned by this function may not
+   * result in the desired topic name being used depending on the remap rules in use.
+   *
+   * \param[in] node_name name of the node
+   * \param[in] namespace_ namespace of the node
+   * \param[in] no_demangle if true, topic names and types are not demangled
+   */
+  RCLCPP_PUBLIC
+  virtual
+  std::map<std::string, std::vector<std::string>>
+  get_publisher_names_and_types_by_node(
+    const std::string & node_name,
+    const std::string & namespace_,
+    bool no_demangle = false) const = 0;
+
+  /// Return a map of existing topic names to list of topic types for a specific node.
+  /**
+   * This function only considers subscribers - not publishers.
+   * The returned names are the actual names after remap rules applied.
+   * Attempting to create publishers or subscribers using names returned by this function may not
+   * result in the desired topic name being used depending on the remap rules in use.
+   *
+   * \param[in] node_name name of the node
+   * \param[in] namespace_ namespace of the node
+   * \param[in] no_demangle if true, topic names and types are not demangled
+   */
+  RCLCPP_PUBLIC
+  virtual
+  std::map<std::string, std::vector<std::string>>
+  get_subscriber_names_and_types_by_node(
+    const std::string & node_name,
+    const std::string & namespace_,
+    bool no_demangle = false) const = 0;
+
   /// Return a vector of existing node names (string).
   /*
-   * The returned names are the actual names used and do not have remap rules applied.
+   * The returned names are the actual names after remap rules applied.
    */
   RCLCPP_PUBLIC
   virtual
   std::vector<std::string>
   get_node_names() const = 0;
 
+  /// Return a vector of existing node names, namespaces and enclaves (tuple of string).
+  /*
+   * The returned names are the actual names after remap rules applied.
+   * The enclaves contain the runtime security artifacts, those can be
+   * used to establish secured network.
+   * See https://design.ros2.org/articles/ros2_security_enclaves.html
+   */
+  RCLCPP_PUBLIC
+  virtual
+  std::vector<std::tuple<std::string, std::string, std::string>>
+  get_node_names_with_enclaves() const = 0;
+
   /// Return a vector of existing node names and namespaces (pair of string).
   /*
-   * The returned names are the actual names used and do not have remap rules applied.
+   * The returned names are the actual names after remap rules applied.
    */
   RCLCPP_PUBLIC
   virtual
@@ -283,6 +362,8 @@ public:
   /// Return the topic endpoint information about publishers on a given topic.
   /**
    * \param[in] topic_name the actual topic name used; it will not be automatically remapped.
+   * \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.
    * \sa rclcpp::Node::get_publishers_info_by_topic
    */
   RCLCPP_PUBLIC
@@ -293,6 +374,8 @@ public:
   /// Return the topic endpoint information about subscriptions on a given topic.
   /**
    * \param[in] topic_name the actual topic name used; it will not be automatically remapped.
+   * \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.
    * \sa rclcpp::Node::get_subscriptions_info_by_topic
    */
   RCLCPP_PUBLIC
@@ -304,4 +387,6 @@ public:
 }  // namespace node_interfaces
 }  // namespace rclcpp
 
+RCLCPP_NODE_INTERFACE_HELPERS_SUPPORT(rclcpp::node_interfaces::NodeGraphInterface, graph)
+
 #endif  // RCLCPP__NODE_INTERFACES__NODE_GRAPH_INTERFACE_HPP_

rclcpp/include/rclcpp/node_interfaces/node_interfaces.hpp

@@ -0,0 +1,171 @@
+// Copyright 2022 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__NODE_INTERFACES_HPP_
+#define RCLCPP__NODE_INTERFACES__NODE_INTERFACES_HPP_
+
+#include <memory>
+
+#include "rclcpp/detail/template_unique.hpp"
+#include "rclcpp/node_interfaces/detail/node_interfaces_helpers.hpp"
+
+#define ALL_RCLCPP_NODE_INTERFACES \
+  rclcpp::node_interfaces::NodeBaseInterface, \
+  rclcpp::node_interfaces::NodeClockInterface, \
+  rclcpp::node_interfaces::NodeGraphInterface, \
+  rclcpp::node_interfaces::NodeLoggingInterface, \
+  rclcpp::node_interfaces::NodeParametersInterface, \
+  rclcpp::node_interfaces::NodeServicesInterface, \
+  rclcpp::node_interfaces::NodeTimeSourceInterface, \
+  rclcpp::node_interfaces::NodeTimersInterface, \
+  rclcpp::node_interfaces::NodeTopicsInterface, \
+  rclcpp::node_interfaces::NodeWaitablesInterface
+
+
+namespace rclcpp
+{
+namespace node_interfaces
+{
+
+
+/// A helper class for aggregating node interfaces.
+template<typename ... InterfaceTs>
+class NodeInterfaces
+  : public detail::NodeInterfacesSupportCheck<
+    detail::NodeInterfacesStorage<InterfaceTs ...>,
+    InterfaceTs ...
+  >,
+  public detail::NodeInterfacesSupports<
+    detail::NodeInterfacesStorage<InterfaceTs ...>,
+    InterfaceTs ...
+  >
+{
+  static_assert(
+    0 != sizeof ...(InterfaceTs),
+    "must provide at least one interface as a template argument");
+  static_assert(
+    rclcpp::detail::template_unique_v<InterfaceTs ...>,
+    "must provide unique template parameters");
+
+  using NodeInterfacesSupportsT = detail::NodeInterfacesSupports<
+    detail::NodeInterfacesStorage<InterfaceTs ...>,
+    InterfaceTs ...
+  >;
+
+public:
+  /// Create a new NodeInterfaces object using the given node-like object's interfaces.
+  /**
+   * Specify which interfaces you need by passing them as template parameters.
+   *
+   * This allows you to aggregate interfaces from different sources together to pass as a single
+   * aggregate object to any functions that take node interfaces or node-likes, without needing to
+   * templatize that function.
+   *
+   * You may also use this constructor to create a NodeInterfaces that contains a subset of
+   * another NodeInterfaces' interfaces.
+   *
+   * Finally, this class supports implicit conversion from node-like objects, allowing you to
+   * directly pass a node-like to a function that takes a NodeInterfaces object.
+   *
+   * Usage examples:
+   *   ```cpp
+   *   // Suppose we have some function:
+   *   void fn(NodeInterfaces<NodeBaseInterface, NodeClockInterface> interfaces);
+   *
+   *   // Then we can, explicitly:
+   *   rclcpp::Node node("some_node");
+   *   auto ni = NodeInterfaces<NodeBaseInterface, NodeClockInterface>(node);
+   *   fn(ni);
+   *
+   *   // But also:
+   *   fn(node);
+   *
+   *   // Subsetting a NodeInterfaces object also works!
+   *   auto ni_base = NodeInterfaces<NodeBaseInterface>(ni);
+   *
+   *   // Or aggregate them (you could aggregate interfaces from disparate node-likes)
+   *   auto ni_aggregated = NodeInterfaces<NodeBaseInterface, NodeClockInterface>(
+   *     node->get_node_base_interface(),
+   *     node->get_node_clock_interface()
+   *   )
+   *
+   *   // And then to access the interfaces:
+   *   // Get with get<>
+   *   auto base = ni.get<NodeBaseInterface>();
+   *
+   *   // Or the appropriate getter
+   *   auto clock = ni.get_clock_interface();
+   *   ```
+   *
+   * You may use any of the standard node interfaces that come with rclcpp:
+   *   - rclcpp::node_interfaces::NodeBaseInterface
+   *   - rclcpp::node_interfaces::NodeClockInterface
+   *   - rclcpp::node_interfaces::NodeGraphInterface
+   *   - rclcpp::node_interfaces::NodeLoggingInterface
+   *   - rclcpp::node_interfaces::NodeParametersInterface
+   *   - rclcpp::node_interfaces::NodeServicesInterface
+   *   - rclcpp::node_interfaces::NodeTimeSourceInterface
+   *   - rclcpp::node_interfaces::NodeTimersInterface
+   *   - rclcpp::node_interfaces::NodeTopicsInterface
+   *   - rclcpp::node_interfaces::NodeWaitablesInterface
+   *
+   * Or you use custom interfaces as long as you make a template specialization
+   * of the rclcpp::node_interfaces::detail::NodeInterfacesSupport struct using
+   * the RCLCPP_NODE_INTERFACE_HELPERS_SUPPORT macro.
+   *
+   * Usage example:
+   *   ```RCLCPP_NODE_INTERFACE_HELPERS_SUPPORT(rclcpp::node_interfaces::NodeBaseInterface, base)```
+   *
+   * If you choose not to use the helper macro, then you can specialize the
+   * template yourself, but you must:
+   *
+   *   - Provide a template specialization of the get_from_node_like method that gets the interface
+   *     from any node-like that stores the interface, using the node-like's getter
+   *   - Designate the is_supported type as std::true_type using a using directive
+   *   - Provide any number of getter methods to be used to obtain the interface with the
+   *     NodeInterface object, noting that the getters of the storage class will apply to all
+   *     supported interfaces.
+   *     - The getter method names should not clash in name with any other interface getter
+   *       specializations if those other interfaces are meant to be aggregated in the same
+   *       NodeInterfaces object.
+   *
+   * \param[in] node Node-like object from which to get the node interfaces
+   */
+  template<typename NodeT>
+  NodeInterfaces(NodeT & node)  // NOLINT(runtime/explicit)
+  : NodeInterfacesSupportsT(node)
+  {}
+
+  /// NodeT::SharedPtr Constructor
+  template<typename NodeT>
+  NodeInterfaces(std::shared_ptr<NodeT> node)  // NOLINT(runtime/explicit)
+  : NodeInterfaces(
+      [&]() -> NodeT & {
+        if (!node) {
+          throw std::invalid_argument("given node pointer is nullptr");
+        }
+        return *node;
+      }())
+  {}
+
+  explicit NodeInterfaces(std::shared_ptr<InterfaceTs>... args)
+  : NodeInterfacesSupportsT(args ...)
+  {}
+};
+
+
+}  // namespace node_interfaces
+}  // namespace rclcpp
+
+#endif  // RCLCPP__NODE_INTERFACES__NODE_INTERFACES_HPP_

rclcpp/include/rclcpp/node_interfaces/node_logging_interface.hpp

@@ -19,6 +19,7 @@
 
 #include "rclcpp/logger.hpp"
 #include "rclcpp/macros.hpp"
+#include "rclcpp/node_interfaces/detail/node_interfaces_helpers.hpp"
 #include "rclcpp/visibility_control.hpp"
 
 namespace rclcpp
@@ -54,4 +55,6 @@ public:
 }  // namespace node_interfaces
 }  // namespace rclcpp
 
+RCLCPP_NODE_INTERFACE_HELPERS_SUPPORT(rclcpp::node_interfaces::NodeLoggingInterface, logging)
+
 #endif  // RCLCPP__NODE_INTERFACES__NODE_LOGGING_INTERFACE_HPP_

rclcpp/include/rclcpp/node_interfaces/node_parameters.hpp

@@ -103,25 +103,6 @@ public:
   virtual
   ~NodeParameters();
 
-// This is overriding a deprecated method, so we need to ignore the deprecation warning here.
-// Users of the method will still get a warning!
-#ifndef _WIN32
-# pragma GCC diagnostic push
-# pragma GCC diagnostic ignored "-Wdeprecated-declarations"
-#else
-# pragma warning(push)
-# pragma warning(disable: 4996)
-#endif
-  [[deprecated(RCLCPP_INTERNAL_NODE_PARAMETERS_INTERFACE_DEPRECATE_DECLARE)]]
-  RCLCPP_PUBLIC
-  const rclcpp::ParameterValue &
-  declare_parameter(const std::string & name) override;
-#ifndef _WIN32
-# pragma GCC diagnostic pop
-#else
-# pragma warning(pop)
-#endif
-
   RCLCPP_PUBLIC
   const rclcpp::ParameterValue &
   declare_parameter(

rclcpp/include/rclcpp/node_interfaces/node_parameters_interface.hpp

@@ -25,6 +25,7 @@
 #include "rcl_interfaces/msg/set_parameters_result.hpp"
 
 #include "rclcpp/macros.hpp"
+#include "rclcpp/node_interfaces/detail/node_interfaces_helpers.hpp"
 #include "rclcpp/parameter.hpp"
 #include "rclcpp/visibility_control.hpp"
 
@@ -45,17 +46,6 @@ struct OnSetParametersCallbackHandle
   OnParametersSetCallbackType callback;
 };
 
-#define RCLCPP_INTERNAL_NODE_PARAMETERS_INTERFACE_DEPRECATE_DECLARE \
-  "declare_parameter() with only a name is deprecated and will be deleted in the future.\n" \
-  "If you want to declare a parameter that won't change type without a default value use:\n" \
-  "`node_params->declare_parameter(name, type)`, with e.g. type=rclcpp::PARAMETER_INTEGER.\n\n" \
-  "If you want to declare a parameter that can dynamically change type use:\n" \
-  "```\n" \
-  "rcl_interfaces::msg::ParameterDescriptor descriptor;\n" \
-  "descriptor.dynamic_typing = true;\n" \
-  "node_params->declare_parameter(name, rclcpp::ParameterValue{}, descriptor);\n" \
-  "```"
-
 /// Pure virtual interface class for the NodeParameters part of the Node API.
 class NodeParametersInterface
 {
@@ -66,15 +56,6 @@ public:
   virtual
   ~NodeParametersInterface() = default;
 
-  /// Declare a parameter.
-  /**
-   * \sa rclcpp::Node::declare_parameter
-   */
-  [[deprecated(RCLCPP_INTERNAL_NODE_PARAMETERS_INTERFACE_DEPRECATE_DECLARE)]]
-  virtual
-  const rclcpp::ParameterValue &
-  declare_parameter(const std::string & name) = 0;
-
   /// Declare and initialize a parameter.
   /**
    * \sa rclcpp::Node::declare_parameter
@@ -235,4 +216,6 @@ public:
 }  // namespace node_interfaces
 }  // namespace rclcpp
 
+RCLCPP_NODE_INTERFACE_HELPERS_SUPPORT(rclcpp::node_interfaces::NodeParametersInterface, parameters)
+
 #endif  // RCLCPP__NODE_INTERFACES__NODE_PARAMETERS_INTERFACE_HPP_

rclcpp/include/rclcpp/node_interfaces/node_services_interface.hpp

@@ -20,6 +20,7 @@
 #include "rclcpp/callback_group.hpp"
 #include "rclcpp/client.hpp"
 #include "rclcpp/macros.hpp"
+#include "rclcpp/node_interfaces/detail/node_interfaces_helpers.hpp"
 #include "rclcpp/service.hpp"
 #include "rclcpp/visibility_control.hpp"
 
@@ -62,4 +63,6 @@ public:
 }  // namespace node_interfaces
 }  // namespace rclcpp
 
+RCLCPP_NODE_INTERFACE_HELPERS_SUPPORT(rclcpp::node_interfaces::NodeServicesInterface, services)
+
 #endif  // RCLCPP__NODE_INTERFACES__NODE_SERVICES_INTERFACE_HPP_

rclcpp/include/rclcpp/node_interfaces/node_time_source.hpp

@@ -48,7 +48,7 @@ public:
     rclcpp::node_interfaces::NodeLoggingInterface::SharedPtr node_logging,
     rclcpp::node_interfaces::NodeClockInterface::SharedPtr node_clock,
     rclcpp::node_interfaces::NodeParametersInterface::SharedPtr node_parameters,
-    const rclcpp::QoS & qos = rclcpp::RosoutQoS(),
+    const rclcpp::QoS & qos = rclcpp::ClockQoS(),
     bool use_clock_thread = true
   );
 

rclcpp/include/rclcpp/node_interfaces/node_time_source_interface.hpp

@@ -16,6 +16,7 @@
 #define RCLCPP__NODE_INTERFACES__NODE_TIME_SOURCE_INTERFACE_HPP_
 
 #include "rclcpp/macros.hpp"
+#include "rclcpp/node_interfaces/detail/node_interfaces_helpers.hpp"
 #include "rclcpp/visibility_control.hpp"
 
 namespace rclcpp
@@ -37,4 +38,6 @@ public:
 }  // namespace node_interfaces
 }  // namespace rclcpp
 
+RCLCPP_NODE_INTERFACE_HELPERS_SUPPORT(rclcpp::node_interfaces::NodeTimeSourceInterface, time_source)
+
 #endif  // RCLCPP__NODE_INTERFACES__NODE_TIME_SOURCE_INTERFACE_HPP_

rclcpp/include/rclcpp/node_interfaces/node_timers_interface.hpp

@@ -17,6 +17,7 @@
 
 #include "rclcpp/callback_group.hpp"
 #include "rclcpp/macros.hpp"
+#include "rclcpp/node_interfaces/detail/node_interfaces_helpers.hpp"
 #include "rclcpp/timer.hpp"
 #include "rclcpp/visibility_control.hpp"
 
@@ -47,4 +48,6 @@ public:
 }  // namespace node_interfaces
 }  // namespace rclcpp
 
+RCLCPP_NODE_INTERFACE_HELPERS_SUPPORT(rclcpp::node_interfaces::NodeTimersInterface, timers)
+
 #endif  // RCLCPP__NODE_INTERFACES__NODE_TIMERS_INTERFACE_HPP_

rclcpp/include/rclcpp/node_interfaces/node_topics.hpp

@@ -20,12 +20,16 @@
 #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/node_interfaces/node_topics_interface.hpp"
-#include "rclcpp/publisher.hpp"
+#include "rclcpp/publisher_base.hpp"
 #include "rclcpp/publisher_factory.hpp"
+#include "rclcpp/qos.hpp"
+#include "rclcpp/subscription_base.hpp"
+#include "rclcpp/subscription_factory.hpp"
 #include "rclcpp/visibility_control.hpp"
 
 namespace rclcpp

rclcpp/include/rclcpp/node_interfaces/node_topics_interface.hpp

@@ -24,6 +24,7 @@
 
 #include "rclcpp/callback_group.hpp"
 #include "rclcpp/macros.hpp"
+#include "rclcpp/node_interfaces/detail/node_interfaces_helpers.hpp"
 #include "rclcpp/node_interfaces/node_base_interface.hpp"
 #include "rclcpp/node_interfaces/node_timers_interface.hpp"
 #include "rclcpp/publisher.hpp"
@@ -97,4 +98,6 @@ public:
 }  // namespace node_interfaces
 }  // namespace rclcpp
 
+RCLCPP_NODE_INTERFACE_HELPERS_SUPPORT(rclcpp::node_interfaces::NodeTopicsInterface, topics)
+
 #endif  // RCLCPP__NODE_INTERFACES__NODE_TOPICS_INTERFACE_HPP_

rclcpp/include/rclcpp/node_interfaces/node_waitables_interface.hpp

@@ -17,6 +17,7 @@
 
 #include "rclcpp/callback_group.hpp"
 #include "rclcpp/macros.hpp"
+#include "rclcpp/node_interfaces/detail/node_interfaces_helpers.hpp"
 #include "rclcpp/visibility_control.hpp"
 #include "rclcpp/waitable.hpp"
 
@@ -54,4 +55,6 @@ public:
 }  // namespace node_interfaces
 }  // namespace rclcpp
 
+RCLCPP_NODE_INTERFACE_HELPERS_SUPPORT(rclcpp::node_interfaces::NodeWaitablesInterface, waitables)
+
 #endif  // RCLCPP__NODE_INTERFACES__NODE_WAITABLES_INTERFACE_HPP_

rclcpp/include/rclcpp/node_options.hpp

@@ -42,6 +42,7 @@ public:
    *   - arguments = {}
    *   - parameter_overrides = {}
    *   - use_global_arguments = true
+   *   - enable_rosout = true
    *   - use_intra_process_comms = false
    *   - enable_topic_statistics = false
    *   - start_parameter_services = true
@@ -349,6 +350,9 @@ public:
    * global arguments (e.g. parameter overrides from a YAML file), which are
    * not explicitly declared will not appear on the node at all, even if
    * `allow_undeclared_parameters` is true.
+   * Parameter declaration from overrides is done in the node's base constructor,
+   * so the user must take care to check if the parameter is already (e.g.
+   * automatically) declared before declaring it themselves.
    * Already declared parameters will not be re-declared, and parameters
    * declared in this way will use the default constructed ParameterDescriptor.
    */

rclcpp/include/rclcpp/parameter.hpp

@@ -264,6 +264,7 @@ get_value_helper<rclcpp::Parameter>(const rclcpp::Parameter * parameter)
 
 }  // namespace detail
 
+/// \cond
 template<typename T>
 decltype(auto)
 Parameter::get_value() const
@@ -275,6 +276,7 @@ Parameter::get_value() const
     throw exceptions::InvalidParameterTypeException(this->name_, ex.what());
   }
 }
+/// \endcond
 
 }  // namespace rclcpp
 

rclcpp/include/rclcpp/parameter_client.hpp

@@ -79,7 +79,7 @@ public:
    * \param[in] group (optional) The async parameter client will be added to this callback group.
    */
   template<typename NodeT>
-  AsyncParametersClient(
+  explicit AsyncParametersClient(
     const std::shared_ptr<NodeT> node,
     const std::string & remote_node_name = "",
     const rmw_qos_profile_t & qos_profile = rmw_qos_profile_parameters,
@@ -102,7 +102,7 @@ public:
    * \param[in] group (optional) The async parameter client will be added to this callback group.
    */
   template<typename NodeT>
-  AsyncParametersClient(
+  explicit AsyncParametersClient(
     NodeT * node,
     const std::string & remote_node_name = "",
     const rmw_qos_profile_t & qos_profile = rmw_qos_profile_parameters,
@@ -185,7 +185,7 @@ public:
   /**
    * This function filters the parameters to be set based on the node name.
    *
-   * \param yaml_filename the full name of the yaml file
+   * \param parameter_map named parameters to be loaded
    * \return the future of the set_parameter service used to load the parameters
    * \throw InvalidParametersException if there is no parameter to set
    */
@@ -333,7 +333,7 @@ public:
   {}
 
   template<typename NodeT>
-  SyncParametersClient(
+  explicit SyncParametersClient(
     NodeT * node,
     const std::string & remote_node_name = "",
     const rmw_qos_profile_t & qos_profile = rmw_qos_profile_parameters)

rclcpp/include/rclcpp/parameter_event_handler.hpp

@@ -165,17 +165,21 @@ public:
    * \param[in] qos The QoS settings to use for any subscriptions.
    */
   template<typename NodeT>
-  ParameterEventHandler(
+  explicit ParameterEventHandler(
     NodeT node,
     const rclcpp::QoS & qos =
     rclcpp::QoS(rclcpp::QoSInitialization::from_rmw(rmw_qos_profile_parameter_events)))
+  : node_base_(rclcpp::node_interfaces::get_node_base_interface(node))
   {
-    node_base_ = rclcpp::node_interfaces::get_node_base_interface(node);
     auto node_topics = rclcpp::node_interfaces::get_node_topics_interface(node);
 
+    callbacks_ = std::make_shared<Callbacks>();
+
     event_subscription_ = rclcpp::create_subscription<rcl_interfaces::msg::ParameterEvent>(
       node_topics, "/parameter_events", qos,
-      std::bind(&ParameterEventHandler::event_callback, this, std::placeholders::_1));
+      [callbacks = callbacks_](const rcl_interfaces::msg::ParameterEvent & event) {
+        callbacks->event_callback(event);
+      });
   }
 
   using ParameterEventCallbackType =
@@ -249,8 +253,8 @@ public:
   get_parameter_from_event(
     const rcl_interfaces::msg::ParameterEvent & event,
     rclcpp::Parameter & parameter,
-    const std::string parameter_name,
-    const std::string node_name = "");
+    const std::string & parameter_name,
+    const std::string & node_name = "");
 
   /// Get an rclcpp::Parameter from parameter event
   /**
@@ -269,8 +273,8 @@ public:
   static rclcpp::Parameter
   get_parameter_from_event(
     const rcl_interfaces::msg::ParameterEvent & event,
-    const std::string parameter_name,
-    const std::string node_name = "");
+    const std::string & parameter_name,
+    const std::string & node_name = "");
 
   /// Get all rclcpp::Parameter values from a parameter event
   /**
@@ -285,17 +289,6 @@ public:
   using CallbacksContainerType = std::list<ParameterCallbackHandle::WeakPtr>;
 
 protected:
-  /// Callback for parameter events subscriptions.
-  RCLCPP_PUBLIC
-  void
-  event_callback(const rcl_interfaces::msg::ParameterEvent & event);
-
-  // Utility function for resolving node path.
-  std::string resolve_path(const std::string & path);
-
-  // Node interface used for base functionality
-  std::shared_ptr<rclcpp::node_interfaces::NodeBaseInterface> node_base_;
-
   // *INDENT-OFF* Uncrustify doesn't handle indented public/private labels
   // Hash function for string pair required in std::unordered_map
   // See: https://stackoverflow.com/questions/35985960/c-why-is-boosthash-combine-the-best-way-to-combine-hash-values
@@ -319,18 +312,34 @@ protected:
   };
   // *INDENT-ON*
 
-  // Map container for registered parameters
-  std::unordered_map<
-    std::pair<std::string, std::string>,
-    CallbacksContainerType,
-    StringPairHash
-  > parameter_callbacks_;
+  struct Callbacks
+  {
+    std::recursive_mutex mutex_;
+
+    // Map container for registered parameters
+    std::unordered_map<
+      std::pair<std::string, std::string>,
+      CallbacksContainerType,
+      StringPairHash
+    > parameter_callbacks_;
+
+    std::list<ParameterEventCallbackHandle::WeakPtr> event_callbacks_;
+
+    /// Callback for parameter events subscriptions.
+    RCLCPP_PUBLIC
+    void
+    event_callback(const rcl_interfaces::msg::ParameterEvent & event);
+  };
+
+  std::shared_ptr<Callbacks> callbacks_;
+
+  // Utility function for resolving node path.
+  std::string resolve_path(const std::string & path);
+
+  // Node interface used for base functionality
+  std::shared_ptr<rclcpp::node_interfaces::NodeBaseInterface> node_base_;
 
   rclcpp::Subscription<rcl_interfaces::msg::ParameterEvent>::SharedPtr event_subscription_;
-
-  std::list<ParameterEventCallbackHandle::WeakPtr> event_callbacks_;
-
-  std::recursive_mutex mutex_;
 };
 
 }  // namespace rclcpp

rclcpp/include/rclcpp/parameter_events_filter.hpp

@@ -45,6 +45,7 @@ public:
    * \param[in] names A list of parameter names of interest.
    * \param[in] types A list of the types of parameter events of iterest.
    *    EventType NEW, DELETED, or CHANGED
+   * \throws std::invalid_argument if event is NULL.
    *
    * Example Usage:
    *

rclcpp/include/rclcpp/parameter_map.hpp

@@ -41,6 +41,16 @@ RCLCPP_PUBLIC
 ParameterMap
 parameter_map_from(const rcl_params_t * const c_params);
 
+/// Convert parameters from rcl_yaml_param_parser into C++ class instances.
+/// \param[in] c_params C structures containing parameters for multiple nodes.
+/// \param[in] node_fqn a Fully Qualified Name of node, default value is nullptr.
+///   If it's not nullptr, return the relative node parameters belonging to this node_fqn.
+/// \returns a map where the keys are fully qualified node names and values a list of parameters.
+/// \throws InvalidParametersException if the `rcl_params_t` is inconsistent or invalid.
+RCLCPP_PUBLIC
+ParameterMap
+parameter_map_from(const rcl_params_t * const c_params, const char * node_fqn);
+
 /// Convert parameter value from rcl_yaml_param_parser into a C++ class instance.
 /// \param[in] c_value C structure containing a value of a parameter.
 /// \returns an instance of a parameter value

rclcpp/include/rclcpp/parameter_value.hpp

@@ -301,6 +301,16 @@ public:
     return get<ParameterType::PARAMETER_BOOL_ARRAY>();
   }
 
+  template<typename type>
+  constexpr
+  typename std::enable_if<
+    std::is_convertible<
+      type, const std::vector<int> &>::value, const std::vector<int64_t> &>::type
+  get() const
+  {
+    return get<ParameterType::PARAMETER_INTEGER_ARRAY>();
+  }
+
   template<typename type>
   constexpr
   typename std::enable_if<
@@ -311,6 +321,16 @@ public:
     return get<ParameterType::PARAMETER_INTEGER_ARRAY>();
   }
 
+  template<typename type>
+  constexpr
+  typename std::enable_if<
+    std::is_convertible<
+      type, const std::vector<float> &>::value, const std::vector<double> &>::type
+  get() const
+  {
+    return get<ParameterType::PARAMETER_DOUBLE_ARRAY>();
+  }
+
   template<typename type>
   constexpr
   typename std::enable_if<

rclcpp/include/rclcpp/publisher.hpp

@@ -20,12 +20,14 @@
 #include <memory>
 #include <sstream>
 #include <string>
+#include <type_traits>
 #include <utility>
 
 #include "rcl/error_handling.h"
 #include "rcl/publisher.h"
 #include "rmw/error_handling.h"
 #include "rmw/rmw.h"
+#include "rosidl_runtime_cpp/traits.hpp"
 
 #include "rclcpp/allocator/allocator_common.hpp"
 #include "rclcpp/allocator/allocator_deleter.hpp"
@@ -81,7 +83,6 @@ public:
 
   /// MessageT::custom_type if MessageT is a TypeAdapter, otherwise just MessageT.
   using PublishedType = typename rclcpp::TypeAdapter<MessageT>::custom_type;
-  /// MessageT::ros_message_type if MessageT is a TypeAdapter, otherwise just MessageT.
   using ROSMessageType = typename rclcpp::TypeAdapter<MessageT>::ros_message_type;
 
   using PublishedTypeAllocatorTraits = allocator::AllocRebind<PublishedType, AllocatorT>;
@@ -176,8 +177,7 @@ public:
     const rclcpp::QoS & qos,
     const rclcpp::PublisherOptionsWithAllocator<AllocatorT> & options)
   {
-    // Topic is unused for now.
-    (void)topic;
+    (void)qos;
     (void)options;
 
     // If needed, setup intra process communication.
@@ -185,19 +185,23 @@ public:
       auto context = node_base->get_context();
       // Get the intra process manager instance for this context.
       auto ipm = context->get_sub_context<rclcpp::experimental::IntraProcessManager>();
-      // Register the publisher with the intra process manager.
-      if (qos.history() != rclcpp::HistoryPolicy::KeepLast) {
+      // Check if the QoS is compatible with intra-process.
+      auto qos_profile = get_actual_qos();
+      if (qos_profile.history() != rclcpp::HistoryPolicy::KeepLast) {
         throw std::invalid_argument(
-                "intraprocess communication allowed only with keep last history qos policy");
+                "intraprocess communication on topic '" + topic +
+                "' allowed only with keep last history qos policy");
       }
-      if (qos.depth() == 0) {
+      if (qos_profile.depth() == 0) {
         throw std::invalid_argument(
-                "intraprocess communication is not allowed with a zero qos history depth value");
+                "intraprocess communication on topic '" + topic +
+                "' is not allowed with a zero qos history depth value");
       }
-      if (qos.durability() != rclcpp::DurabilityPolicy::Volatile) {
+      if (qos_profile.durability() != rclcpp::DurabilityPolicy::Volatile) {
         throw std::invalid_argument(
                 "intraprocess communication allowed only with volatile durability");
       }
+      // Register the publisher with the intra process manager.
       uint64_t intra_process_publisher_id = ipm->add_publisher(this->shared_from_this());
       this->setup_intra_process(
         intra_process_publisher_id,
@@ -263,10 +267,11 @@ public:
       get_subscription_count() > get_intra_process_subscription_count();
 
     if (inter_process_publish_needed) {
-      auto shared_msg = this->do_intra_process_publish_and_return_shared(std::move(msg));
+      auto shared_msg =
+        this->do_intra_process_ros_message_publish_and_return_shared(std::move(msg));
       this->do_inter_process_publish(*shared_msg);
     } else {
-      this->do_intra_process_publish(std::move(msg));
+      this->do_intra_process_ros_message_publish(std::move(msg));
     }
   }
 
@@ -319,13 +324,28 @@ public:
   >
   publish(std::unique_ptr<T, PublishedTypeDeleter> msg)
   {
-    // TODO(wjwwood): later update this to give the unique_ptr to the intra
-    // process manager and let it decide if it needs to be converted or not.
-    // For now, convert it unconditionally and pass it the ROSMessageType
-    // publish function specialization.
-    auto unique_ros_msg = this->create_ros_message_unique_ptr();
-    rclcpp::TypeAdapter<MessageT>::convert_to_ros_message(*msg, *unique_ros_msg);
-    this->publish(std::move(unique_ros_msg));
+    // Avoid allocating when not using intra process.
+    if (!intra_process_is_enabled_) {
+      // In this case we're not using intra process.
+      ROSMessageType ros_msg;
+      rclcpp::TypeAdapter<MessageT>::convert_to_ros_message(*msg, ros_msg);
+      return this->do_inter_process_publish(ros_msg);
+    }
+
+    bool inter_process_publish_needed =
+      get_subscription_count() > get_intra_process_subscription_count();
+
+    if (inter_process_publish_needed) {
+      ROSMessageType ros_msg;
+      // TODO(clalancette): This is unnecessarily doing an additional conversion
+      // that may have already been done in do_intra_process_publish_and_return_shared().
+      // We should just reuse that effort.
+      rclcpp::TypeAdapter<MessageT>::convert_to_ros_message(*msg, ros_msg);
+      this->do_intra_process_publish(std::move(msg));
+      this->do_inter_process_publish(ros_msg);
+    } else {
+      this->do_intra_process_publish(std::move(msg));
+    }
   }
 
   /// Publish a message on the topic.
@@ -346,12 +366,7 @@ public:
   >
   publish(const T & msg)
   {
-    // TODO(wjwwood): later update this to give the unique_ptr to the intra
-    // process manager and let it decide if it needs to be converted or not.
-    // For now, convert it unconditionally and pass it the ROSMessageType
-    // publish function specialization.
-
-    // Avoid allocating when not using intra process.
+    // Avoid double allocating when not using intra process.
     if (!intra_process_is_enabled_) {
       // Convert to the ROS message equivalent and publish it.
       ROSMessageType ros_msg;
@@ -359,13 +374,12 @@ public:
       // In this case we're not using intra process.
       return this->do_inter_process_publish(ros_msg);
     }
-    // Otherwise we have to allocate memory in a unique_ptr, convert it,
-    // and pass it along.
+
+    // Otherwise we have to allocate memory in a unique_ptr and pass it along.
     // As the message is not const, a copy should be made.
     // A shared_ptr<const MessageT> could also be constructed here.
-    auto unique_ros_msg = this->create_ros_message_unique_ptr();
-    rclcpp::TypeAdapter<MessageT>::convert_to_ros_message(msg, *unique_ros_msg);
-    this->publish(std::move(unique_ros_msg));
+    auto unique_msg = this->duplicate_type_adapt_message_as_unique_ptr(msg);
+    this->publish(std::move(unique_msg));
   }
 
   void
@@ -438,10 +452,7 @@ protected:
   void
   do_inter_process_publish(const ROSMessageType & msg)
   {
-    TRACEPOINT(
-      rclcpp_publish,
-      static_cast<const void *>(publisher_handle_.get()),
-      static_cast<const void *>(&msg));
+    TRACEPOINT(rclcpp_publish, nullptr, static_cast<const void *>(&msg));
     auto status = rcl_publish(publisher_handle_.get(), &msg, nullptr);
 
     if (RCL_RET_PUBLISHER_INVALID == status) {
@@ -494,7 +505,7 @@ protected:
   }
 
   void
-  do_intra_process_publish(std::unique_ptr<ROSMessageType, ROSMessageTypeDeleter> msg)
+  do_intra_process_publish(std::unique_ptr<PublishedType, PublishedTypeDeleter> msg)
   {
     auto ipm = weak_ipm_.lock();
     if (!ipm) {
@@ -505,14 +516,32 @@ protected:
       throw std::runtime_error("cannot publish msg which is a null pointer");
     }
 
-    ipm->template do_intra_process_publish<ROSMessageType, AllocatorT>(
+    ipm->template do_intra_process_publish<PublishedType, ROSMessageType, AllocatorT>(
+      intra_process_publisher_id_,
+      std::move(msg),
+      published_type_allocator_);
+  }
+
+  void
+  do_intra_process_ros_message_publish(std::unique_ptr<ROSMessageType, ROSMessageTypeDeleter> msg)
+  {
+    auto ipm = weak_ipm_.lock();
+    if (!ipm) {
+      throw std::runtime_error(
+              "intra process publish called after destruction of intra process manager");
+    }
+    if (!msg) {
+      throw std::runtime_error("cannot publish msg which is a null pointer");
+    }
+
+    ipm->template do_intra_process_publish<ROSMessageType, ROSMessageType, AllocatorT>(
       intra_process_publisher_id_,
       std::move(msg),
       ros_message_type_allocator_);
   }
 
   std::shared_ptr<const ROSMessageType>
-  do_intra_process_publish_and_return_shared(
+  do_intra_process_ros_message_publish_and_return_shared(
     std::unique_ptr<ROSMessageType, ROSMessageTypeDeleter> msg)
   {
     auto ipm = weak_ipm_.lock();
@@ -524,13 +553,14 @@ protected:
       throw std::runtime_error("cannot publish msg which is a null pointer");
     }
 
-    return ipm->template do_intra_process_publish_and_return_shared<ROSMessageType,
+    return ipm->template do_intra_process_publish_and_return_shared<ROSMessageType, ROSMessageType,
              AllocatorT>(
       intra_process_publisher_id_,
       std::move(msg),
       ros_message_type_allocator_);
   }
 
+
   /// Return a new unique_ptr using the ROSMessageType of the publisher.
   std::unique_ptr<ROSMessageType, ROSMessageTypeDeleter>
   create_ros_message_unique_ptr()
@@ -549,6 +579,15 @@ protected:
     return std::unique_ptr<ROSMessageType, ROSMessageTypeDeleter>(ptr, ros_message_type_deleter_);
   }
 
+  /// Duplicate a given type adapted message as a unique_ptr.
+  std::unique_ptr<PublishedType, PublishedTypeDeleter>
+  duplicate_type_adapt_message_as_unique_ptr(const PublishedType & msg)
+  {
+    auto ptr = PublishedTypeAllocatorTraits::allocate(published_type_allocator_, 1);
+    PublishedTypeAllocatorTraits::construct(published_type_allocator_, ptr, msg);
+    return std::unique_ptr<PublishedType, PublishedTypeDeleter>(ptr, published_type_deleter_);
+  }
+
   /// Copy of original options passed during construction.
   /**
    * It is important to save a copy of this so that the rmw payload which it

rclcpp/include/rclcpp/publisher_base.hpp

@@ -18,11 +18,14 @@
 #include <rmw/error_handling.h>
 #include <rmw/rmw.h>
 
+#include <chrono>
 #include <functional>
 #include <iostream>
 #include <memory>
 #include <sstream>
 #include <string>
+#include <unordered_map>
+#include <utility>
 #include <vector>
 
 #include "rcl/publisher.h"
@@ -33,6 +36,7 @@
 #include "rclcpp/qos_event.hpp"
 #include "rclcpp/type_support_decl.hpp"
 #include "rclcpp/visibility_control.hpp"
+#include "rcpputils/time.hpp"
 
 namespace rclcpp
 {
@@ -110,9 +114,10 @@ public:
   get_publisher_handle() const;
 
   /// Get all the QoS event handlers associated with this publisher.
-  /** \return The vector of QoS event handlers. */
+  /** \return The map of QoS event handlers. */
   RCLCPP_PUBLIC
-  const std::vector<std::shared_ptr<rclcpp::QOSEventHandlerBase>> &
+  const
+  std::unordered_map<rcl_publisher_event_type_t, std::shared_ptr<rclcpp::QOSEventHandlerBase>> &
   get_event_handlers() const;
 
   /// Get subscription count
@@ -203,6 +208,111 @@ public:
   std::vector<rclcpp::NetworkFlowEndpoint>
   get_network_flow_endpoints() const;
 
+  /// Wait until all published messages are acknowledged or until the specified timeout elapses.
+  /**
+   * This method waits until all published messages are acknowledged by all matching
+   * subscriptions or the given timeout elapses.
+   *
+   * If the timeout is negative then this method will block indefinitely until all published
+   * messages are acknowledged.
+   * If the timeout is zero then this method will not block, it will check if all published
+   * messages are acknowledged and return immediately.
+   * If the timeout is greater than zero, this method will wait until all published messages are
+   * acknowledged or the timeout elapses.
+   *
+   * This method only waits for acknowledgments if the publisher's QoS profile is RELIABLE.
+   * Otherwise this method will immediately return `true`.
+   *
+   * \param[in] timeout the duration to wait for all published messages to be acknowledged.
+   * \return `true` if all published messages were acknowledged before the given timeout
+   *   elapsed, otherwise `false`.
+   * \throws rclcpp::exceptions::RCLError if middleware doesn't support or internal error occurs
+   * \throws std::invalid_argument if timeout is greater than std::chrono::nanoseconds::max() or
+   *   less than std::chrono::nanoseconds::min()
+   */
+  template<typename DurationRepT = int64_t, typename DurationT = std::milli>
+  bool
+  wait_for_all_acked(
+    std::chrono::duration<DurationRepT, DurationT> timeout =
+    std::chrono::duration<DurationRepT, DurationT>(-1)) const
+  {
+    rcl_duration_value_t rcl_timeout = rcpputils::convert_to_nanoseconds(timeout).count();
+
+    rcl_ret_t ret = rcl_publisher_wait_for_all_acked(publisher_handle_.get(), rcl_timeout);
+    if (ret == RCL_RET_OK) {
+      return true;
+    } else if (ret == RCL_RET_TIMEOUT) {
+      return false;
+    } else {
+      rclcpp::exceptions::throw_from_rcl_error(ret);
+    }
+  }
+
+  /// Set a callback to be called when each new qos event instance occurs.
+  /**
+   * The callback receives a size_t which is the number of events that occurred
+   * since the last time this callback was called.
+   * Normally this is 1, but can be > 1 if events occurred before any
+   * callback was set.
+   *
+   * Since this callback is called from the middleware, you should aim to make
+   * it fast and not blocking.
+   * If you need to do a lot of work or wait for some other event, you should
+   * spin it off to another thread, otherwise you risk blocking the middleware.
+   *
+   * Calling it again will clear any previously set callback.
+   *
+   * An exception will be thrown if the callback is not callable.
+   *
+   * This function is thread-safe.
+   *
+   * If you want more information available in the callback, like the qos event
+   * or other information, you may use a lambda with captures or std::bind.
+   *
+   * \sa rclcpp::QOSEventHandlerBase::set_on_ready_callback
+   *
+   * \param[in] callback functor to be called when a new event occurs
+   * \param[in] event_type identifier for the qos event we want to attach the callback to
+   */
+  void
+  set_on_new_qos_event_callback(
+    std::function<void(size_t)> callback,
+    rcl_publisher_event_type_t event_type)
+  {
+    if (event_handlers_.count(event_type) == 0) {
+      RCLCPP_WARN(
+        rclcpp::get_logger("rclcpp"),
+        "Calling set_on_new_qos_event_callback for non registered publisher event_type");
+      return;
+    }
+
+    if (!callback) {
+      throw std::invalid_argument(
+              "The callback passed to set_on_new_qos_event_callback "
+              "is not callable.");
+    }
+
+    // The on_ready_callback signature has an extra `int` argument used to disambiguate between
+    // possible different entities within a generic waitable.
+    // We hide that detail to users of this method.
+    std::function<void(size_t, int)> new_callback = std::bind(callback, std::placeholders::_1);
+    event_handlers_[event_type]->set_on_ready_callback(new_callback);
+  }
+
+  /// Unset the callback registered for new qos events, if any.
+  void
+  clear_on_new_qos_event_callback(rcl_publisher_event_type_t event_type)
+  {
+    if (event_handlers_.count(event_type) == 0) {
+      RCLCPP_WARN(
+        rclcpp::get_logger("rclcpp"),
+        "Calling clear_on_new_qos_event_callback for non registered event_type");
+      return;
+    }
+
+    event_handlers_[event_type]->clear_on_ready_callback();
+  }
+
 protected:
   template<typename EventCallbackT>
   void
@@ -216,7 +326,7 @@ protected:
       rcl_publisher_event_init,
       publisher_handle_,
       event_type);
-    event_handlers_.emplace_back(handler);
+    event_handlers_.insert(std::make_pair(event_type, handler));
   }
 
   RCLCPP_PUBLIC
@@ -226,7 +336,8 @@ protected:
 
   std::shared_ptr<rcl_publisher_t> publisher_handle_;
 
-  std::vector<std::shared_ptr<rclcpp::QOSEventHandlerBase>> event_handlers_;
+  std::unordered_map<rcl_publisher_event_type_t,
+    std::shared_ptr<rclcpp::QOSEventHandlerBase>> event_handlers_;
 
   using IntraProcessManagerWeakPtr =
     std::weak_ptr<rclcpp::experimental::IntraProcessManager>;
@@ -235,6 +346,8 @@ protected:
   uint64_t intra_process_publisher_id_;
 
   rmw_gid_t rmw_gid_;
+
+  const rosidl_message_type_support_t type_support_;
 };
 
 }  // namespace rclcpp

rclcpp/include/rclcpp/publisher_options.hpp

@@ -72,7 +72,7 @@ struct PublisherOptionsWithAllocator : public PublisherOptionsBase
   /// Optional custom allocator.
   std::shared_ptr<Allocator> allocator = nullptr;
 
-  PublisherOptionsWithAllocator<Allocator>() {}
+  PublisherOptionsWithAllocator() {}
 
   /// Constructor using base class as input.
   explicit PublisherOptionsWithAllocator(const PublisherOptionsBase & publisher_options_base)
@@ -119,6 +119,10 @@ private:
   rcl_allocator_t
   get_rcl_allocator() const
   {
+    if constexpr (std::is_same_v<Allocator, std::allocator<void>>) {
+      return rcl_get_default_allocator();
+    }
+
     if (!plain_allocator_storage_) {
       plain_allocator_storage_ =
         std::make_shared<PlainAllocator>(*this->get_allocator());

rclcpp/include/rclcpp/qos_event.hpp

@@ -17,16 +17,21 @@
 
 #include <functional>
 #include <memory>
+#include <mutex>
 #include <stdexcept>
 #include <string>
 
 #include "rcl/error_handling.h"
+#include "rcl/event_callback.h"
+#include "rmw/impl/cpp/demangle.hpp"
 #include "rmw/incompatible_qos_events_statuses.h"
 
 #include "rcutils/logging_macros.h"
 
+#include "rclcpp/detail/cpp_callback_trampoline.hpp"
 #include "rclcpp/exceptions.hpp"
 #include "rclcpp/function_traits.hpp"
+#include "rclcpp/logging.hpp"
 #include "rclcpp/waitable.hpp"
 
 namespace rclcpp
@@ -84,6 +89,11 @@ public:
 class QOSEventHandlerBase : public Waitable
 {
 public:
+  enum class EntityType : std::size_t
+  {
+    Event,
+  };
+
   RCLCPP_PUBLIC
   virtual ~QOSEventHandlerBase();
 
@@ -94,7 +104,7 @@ public:
 
   /// Add the Waitable to a wait set.
   RCLCPP_PUBLIC
-  bool
+  void
   add_to_wait_set(rcl_wait_set_t * wait_set) override;
 
   /// Check if the Waitable is ready.
@@ -102,9 +112,111 @@ public:
   bool
   is_ready(rcl_wait_set_t * wait_set) override;
 
+  /// Set a callback to be called when each new event instance occurs.
+  /**
+   * The callback receives a size_t which is the number of events that occurred
+   * since the last time this callback was called.
+   * Normally this is 1, but can be > 1 if events occurred before any
+   * callback was set.
+   *
+   * The callback also receives an int identifier argument.
+   * This is needed because a Waitable may be composed of several distinct entities,
+   * such as subscriptions, services, etc.
+   * The application should provide a generic callback function that will be then
+   * forwarded by the waitable to all of its entities.
+   * Before forwarding, a different value for the identifier argument will be
+   * bond to the function.
+   * This implies that the provided callback can use the identifier to behave
+   * differently depending on which entity triggered the waitable to become ready.
+   *
+   * Since this callback is called from the middleware, you should aim to make
+   * it fast and not blocking.
+   * If you need to do a lot of work or wait for some other event, you should
+   * spin it off to another thread, otherwise you risk blocking the middleware.
+   *
+   * Calling it again will clear any previously set callback.
+   *
+   * An exception will be thrown if the callback is not callable.
+   *
+   * This function is thread-safe.
+   *
+   * If you want more information available in the callback, like the qos event
+   * or other information, you may use a lambda with captures or std::bind.
+   *
+   * \sa rmw_event_set_callback
+   * \sa rcl_event_set_callback
+   *
+   * \param[in] callback functor to be called when a new event occurs
+   */
+  void
+  set_on_ready_callback(std::function<void(size_t, int)> callback) override
+  {
+    if (!callback) {
+      throw std::invalid_argument(
+              "The callback passed to set_on_ready_callback "
+              "is not callable.");
+    }
+
+    // Note: we bind the int identifier argument to this waitable's entity types
+    auto new_callback =
+      [callback, this](size_t number_of_events) {
+        try {
+          callback(number_of_events, static_cast<int>(EntityType::Event));
+        } catch (const std::exception & exception) {
+          RCLCPP_ERROR_STREAM(
+            // TODO(wjwwood): get this class access to the node logger it is associated with
+            rclcpp::get_logger("rclcpp"),
+            "rclcpp::QOSEventHandlerBase@" << this <<
+              " caught " << rmw::impl::cpp::demangle(exception) <<
+              " exception in user-provided callback for the 'on ready' callback: " <<
+              exception.what());
+        } catch (...) {
+          RCLCPP_ERROR_STREAM(
+            rclcpp::get_logger("rclcpp"),
+            "rclcpp::QOSEventHandlerBase@" << this <<
+              " caught unhandled exception in user-provided callback " <<
+              "for the 'on ready' callback");
+        }
+      };
+
+    std::lock_guard<std::recursive_mutex> lock(callback_mutex_);
+
+    // Set it temporarily to the new callback, while we replace the old one.
+    // This two-step setting, prevents a gap where the old std::function has
+    // been replaced but the middleware hasn't been told about the new one yet.
+    set_on_new_event_callback(
+      rclcpp::detail::cpp_callback_trampoline<const void *, size_t>,
+      static_cast<const void *>(&new_callback));
+
+    // Store the std::function to keep it in scope, also overwrites the existing one.
+    on_new_event_callback_ = new_callback;
+
+    // Set it again, now using the permanent storage.
+    set_on_new_event_callback(
+      rclcpp::detail::cpp_callback_trampoline<const void *, size_t>,
+      static_cast<const void *>(&on_new_event_callback_));
+  }
+
+  /// Unset the callback registered for new events, if any.
+  void
+  clear_on_ready_callback() override
+  {
+    std::lock_guard<std::recursive_mutex> lock(callback_mutex_);
+    if (on_new_event_callback_) {
+      set_on_new_event_callback(nullptr, nullptr);
+      on_new_event_callback_ = nullptr;
+    }
+  }
+
 protected:
+  RCLCPP_PUBLIC
+  void
+  set_on_new_event_callback(rcl_event_callback_t callback, const void * user_data);
+
   rcl_event_t event_handle_;
   size_t wait_set_event_index_;
+  std::recursive_mutex callback_mutex_;
+  std::function<void(size_t)> on_new_event_callback_{nullptr};
 };
 
 template<typename EventCallbackT, typename ParentHandleT>
@@ -117,9 +229,8 @@ public:
     InitFuncT init_func,
     ParentHandleT parent_handle,
     EventTypeEnum event_type)
-  : event_callback_(callback)
+  : parent_handle_(parent_handle), event_callback_(callback)
   {
-    parent_handle_ = parent_handle;
     event_handle_ = rcl_get_zero_initialized_event();
     rcl_ret_t ret = init_func(&event_handle_, parent_handle.get(), event_type);
     if (ret != RCL_RET_OK) {
@@ -148,6 +259,13 @@ public:
     return std::static_pointer_cast<void>(std::make_shared<EventCallbackInfoT>(callback_info));
   }
 
+  std::shared_ptr<void>
+  take_data_by_entity_id(size_t id) override
+  {
+    (void)id;
+    return take_data();
+  }
+
   /// Execute any entities of the Waitable that are ready.
   void
   execute(std::shared_ptr<void> & data) override

rclcpp/include/rclcpp/rclcpp.hpp

@@ -140,7 +140,6 @@
  *   - rclcpp/duration.hpp
  *   - rclcpp/function_traits.hpp
  *   - rclcpp/macros.hpp
- *   - rclcpp/scope_exit.hpp
  *   - rclcpp/time.hpp
  *   - rclcpp/utilities.hpp
  *   - rclcpp/typesupport_helpers.hpp

rclcpp/include/rclcpp/scope_exit.hpp

@@ -19,6 +19,10 @@
 #ifndef RCLCPP__SCOPE_EXIT_HPP_
 #define RCLCPP__SCOPE_EXIT_HPP_
 
+// TODO(christophebedard) remove this header completely in I-turtle
+
+#warning rclcpp/scope_exit.hpp has been deprecated, please use rcpputils/scope_exit.hpp instead
+
 #include <functional>
 
 #include "rclcpp/macros.hpp"

rclcpp/include/rclcpp/service.hpp

@@ -19,23 +19,30 @@
 #include <functional>
 #include <iostream>
 #include <memory>
+#include <mutex>
 #include <sstream>
 #include <string>
 
 #include "rcl/error_handling.h"
+#include "rcl/event_callback.h"
 #include "rcl/service.h"
 
-#include "rclcpp/any_service_callback.hpp"
-#include "rclcpp/exceptions.hpp"
-#include "rclcpp/macros.hpp"
-#include "rclcpp/type_support_decl.hpp"
-#include "rclcpp/expand_topic_or_service_name.hpp"
-#include "rclcpp/visibility_control.hpp"
-#include "rclcpp/logging.hpp"
 #include "rmw/error_handling.h"
+#include "rmw/impl/cpp/demangle.hpp"
 #include "rmw/rmw.h"
+
 #include "tracetools/tracetools.h"
 
+#include "rclcpp/any_service_callback.hpp"
+#include "rclcpp/detail/cpp_callback_trampoline.hpp"
+#include "rclcpp/exceptions.hpp"
+#include "rclcpp/expand_topic_or_service_name.hpp"
+#include "rclcpp/logging.hpp"
+#include "rclcpp/macros.hpp"
+#include "rclcpp/qos.hpp"
+#include "rclcpp/type_support_decl.hpp"
+#include "rclcpp/visibility_control.hpp"
+
 namespace rclcpp
 {
 
@@ -121,6 +128,123 @@ public:
   bool
   exchange_in_use_by_wait_set_state(bool in_use_state);
 
+  /// Get the actual response publisher QoS settings, after the defaults have been determined.
+  /**
+   * The actual configuration applied when using RMW_QOS_POLICY_*_SYSTEM_DEFAULT
+   * can only be resolved after the creation of the service, and it
+   * depends on the underlying rmw implementation.
+   * If the underlying setting in use can't be represented in ROS terms,
+   * it will be set to RMW_QOS_POLICY_*_UNKNOWN.
+   * May throw runtime_error when an unexpected error occurs.
+   *
+   * \return The actual response publisher qos settings.
+   * \throws std::runtime_error if failed to get qos settings
+   */
+  RCLCPP_PUBLIC
+  rclcpp::QoS
+  get_response_publisher_actual_qos() const;
+
+  /// Get the actual request subscription QoS settings, after the defaults have been determined.
+  /**
+   * The actual configuration applied when using RMW_QOS_POLICY_*_SYSTEM_DEFAULT
+   * can only be resolved after the creation of the service, and it
+   * depends on the underlying rmw implementation.
+   * If the underlying setting in use can't be represented in ROS terms,
+   * it will be set to RMW_QOS_POLICY_*_UNKNOWN.
+   * May throw runtime_error when an unexpected error occurs.
+   *
+   * \return The actual request subscription qos settings.
+   * \throws std::runtime_error if failed to get qos settings
+   */
+  RCLCPP_PUBLIC
+  rclcpp::QoS
+  get_request_subscription_actual_qos() const;
+
+  /// Set a callback to be called when each new request is received.
+  /**
+   * The callback receives a size_t which is the number of requests received
+   * since the last time this callback was called.
+   * Normally this is 1, but can be > 1 if requests were received before any
+   * callback was set.
+   *
+   * Since this callback is called from the middleware, you should aim to make
+   * it fast and not blocking.
+   * If you need to do a lot of work or wait for some other event, you should
+   * spin it off to another thread, otherwise you risk blocking the middleware.
+   *
+   * Calling it again will clear any previously set callback.
+   *
+   *
+   * An exception will be thrown if the callback is not callable.
+   *
+   * This function is thread-safe.
+   *
+   * If you want more information available in the callback, like the service
+   * or other information, you may use a lambda with captures or std::bind.
+   *
+   * \sa rmw_service_set_on_new_request_callback
+   * \sa rcl_service_set_on_new_request_callback
+   *
+   * \param[in] callback functor to be called when a new request is received
+   */
+  void
+  set_on_new_request_callback(std::function<void(size_t)> callback)
+  {
+    if (!callback) {
+      throw std::invalid_argument(
+              "The callback passed to set_on_new_request_callback "
+              "is not callable.");
+    }
+
+    auto new_callback =
+      [callback, this](size_t number_of_requests) {
+        try {
+          callback(number_of_requests);
+        } catch (const std::exception & exception) {
+          RCLCPP_ERROR_STREAM(
+            node_logger_,
+            "rclcpp::ServiceBase@" << this <<
+              " caught " << rmw::impl::cpp::demangle(exception) <<
+              " exception in user-provided callback for the 'on new request' callback: " <<
+              exception.what());
+        } catch (...) {
+          RCLCPP_ERROR_STREAM(
+            node_logger_,
+            "rclcpp::ServiceBase@" << this <<
+              " caught unhandled exception in user-provided callback " <<
+              "for the 'on new request' callback");
+        }
+      };
+
+    std::lock_guard<std::recursive_mutex> lock(callback_mutex_);
+
+    // Set it temporarily to the new callback, while we replace the old one.
+    // This two-step setting, prevents a gap where the old std::function has
+    // been replaced but the middleware hasn't been told about the new one yet.
+    set_on_new_request_callback(
+      rclcpp::detail::cpp_callback_trampoline<const void *, size_t>,
+      static_cast<const void *>(&new_callback));
+
+    // Store the std::function to keep it in scope, also overwrites the existing one.
+    on_new_request_callback_ = new_callback;
+
+    // Set it again, now using the permanent storage.
+    set_on_new_request_callback(
+      rclcpp::detail::cpp_callback_trampoline<const void *, size_t>,
+      static_cast<const void *>(&on_new_request_callback_));
+  }
+
+  /// Unset the callback registered for new requests, if any.
+  void
+  clear_on_new_request_callback()
+  {
+    std::lock_guard<std::recursive_mutex> lock(callback_mutex_);
+    if (on_new_request_callback_) {
+      set_on_new_request_callback(nullptr, nullptr);
+      on_new_request_callback_ = nullptr;
+    }
+  }
+
 protected:
   RCLCPP_DISABLE_COPY(ServiceBase)
 
@@ -132,16 +256,27 @@ protected:
   const rcl_node_t *
   get_rcl_node_handle() const;
 
+  RCLCPP_PUBLIC
+  void
+  set_on_new_request_callback(rcl_event_callback_t callback, const void * user_data);
+
   std::shared_ptr<rcl_node_t> node_handle_;
 
   std::shared_ptr<rcl_service_t> service_handle_;
   bool owns_rcl_handle_ = true;
 
+  rclcpp::Logger node_logger_;
+
   std::atomic<bool> in_use_by_wait_set_{false};
+
+  std::recursive_mutex callback_mutex_;
+  std::function<void(size_t)> on_new_request_callback_{nullptr};
 };
 
 template<typename ServiceT>
-class Service : public ServiceBase
+class Service
+  : public ServiceBase,
+  public std::enable_shared_from_this<Service<ServiceT>>
 {
 public:
   using CallbackType = std::function<
@@ -335,9 +470,10 @@ public:
     std::shared_ptr<void> request) override
   {
     auto typed_request = std::static_pointer_cast<typename ServiceT::Request>(request);
-    auto response = std::make_shared<typename ServiceT::Response>();
-    any_callback_.dispatch(request_header, typed_request, response);
-    send_response(*request_header, *response);
+    auto response = any_callback_.dispatch(this->shared_from_this(), request_header, typed_request);
+    if (response) {
+      send_response(*request_header, *response);
+    }
   }
 
   void
@@ -345,6 +481,14 @@ public:
   {
     rcl_ret_t ret = rcl_send_response(get_service_handle().get(), &req_id, &response);
 
+    if (ret == RCL_RET_TIMEOUT) {
+      RCLCPP_WARN(
+        node_logger_.get_child("rclcpp"),
+        "failed to send response to %s (timeout): %s",
+        this->get_service_name(), rcl_get_error_string().str);
+      rcl_reset_error();
+      return;
+    }
     if (ret != RCL_RET_OK) {
       rclcpp::exceptions::throw_from_rcl_error(ret, "failed to send response");
     }

rclcpp/include/rclcpp/strategies/allocator_memory_strategy.hpp

@@ -21,6 +21,7 @@
 #include "rcl/allocator.h"
 
 #include "rclcpp/allocator/allocator_common.hpp"
+#include "rclcpp/detail/add_guard_condition_to_rcl_wait_set.hpp"
 #include "rclcpp/memory_strategy.hpp"
 #include "rclcpp/node.hpp"
 #include "rclcpp/visibility_control.hpp"
@@ -61,17 +62,17 @@ public:
     allocator_ = std::make_shared<VoidAlloc>();
   }
 
-  void add_guard_condition(const rcl_guard_condition_t * guard_condition) override
+  void add_guard_condition(const rclcpp::GuardCondition & guard_condition) override
   {
     for (const auto & existing_guard_condition : guard_conditions_) {
-      if (existing_guard_condition == guard_condition) {
+      if (existing_guard_condition == &guard_condition) {
         return;
       }
     }
-    guard_conditions_.push_back(guard_condition);
+    guard_conditions_.push_back(&guard_condition);
   }
 
-  void remove_guard_condition(const rcl_guard_condition_t * guard_condition) override
+  void remove_guard_condition(const rclcpp::GuardCondition * guard_condition) override
   {
     for (auto it = guard_conditions_.begin(); it != guard_conditions_.end(); ++it) {
       if (*it == guard_condition) {
@@ -163,30 +164,22 @@ public:
       if (!group || !group->can_be_taken_from().load()) {
         continue;
       }
-      group->find_subscription_ptrs_if(
+
+      group->collect_all_ptrs(
         [this](const rclcpp::SubscriptionBase::SharedPtr & subscription) {
           subscription_handles_.push_back(subscription->get_subscription_handle());
-          return false;
-        });
-      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) {
           client_handles_.push_back(client->get_client_handle());
-          return false;
-        });
-      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) {
           waitable_handles_.push_back(waitable);
-          return false;
         });
     }
 
@@ -203,7 +196,7 @@ public:
 
   bool add_handles_to_wait_set(rcl_wait_set_t * wait_set) override
   {
-    for (auto subscription : subscription_handles_) {
+    for (const std::shared_ptr<const rcl_subscription_t> & subscription : subscription_handles_) {
       if (rcl_wait_set_add_subscription(wait_set, subscription.get(), NULL) != RCL_RET_OK) {
         RCUTILS_LOG_ERROR_NAMED(
           "rclcpp",
@@ -212,7 +205,7 @@ public:
       }
     }
 
-    for (auto client : client_handles_) {
+    for (const std::shared_ptr<const rcl_client_t> & client : client_handles_) {
       if (rcl_wait_set_add_client(wait_set, client.get(), NULL) != RCL_RET_OK) {
         RCUTILS_LOG_ERROR_NAMED(
           "rclcpp",
@@ -221,7 +214,7 @@ public:
       }
     }
 
-    for (auto service : service_handles_) {
+    for (const std::shared_ptr<const rcl_service_t> & service : service_handles_) {
       if (rcl_wait_set_add_service(wait_set, service.get(), NULL) != RCL_RET_OK) {
         RCUTILS_LOG_ERROR_NAMED(
           "rclcpp",
@@ -230,7 +223,7 @@ public:
       }
     }
 
-    for (auto timer : timer_handles_) {
+    for (const std::shared_ptr<const rcl_timer_t> & timer : timer_handles_) {
       if (rcl_wait_set_add_timer(wait_set, timer.get(), NULL) != RCL_RET_OK) {
         RCUTILS_LOG_ERROR_NAMED(
           "rclcpp",
@@ -240,22 +233,11 @@ public:
     }
 
     for (auto guard_condition : guard_conditions_) {
-      if (rcl_wait_set_add_guard_condition(wait_set, guard_condition, NULL) != RCL_RET_OK) {
-        RCUTILS_LOG_ERROR_NAMED(
-          "rclcpp",
-          "Couldn't add guard_condition to wait set: %s",
-          rcl_get_error_string().str);
-        return false;
-      }
+      detail::add_guard_condition_to_rcl_wait_set(*wait_set, *guard_condition);
     }
 
-    for (auto waitable : waitable_handles_) {
-      if (!waitable->add_to_wait_set(wait_set)) {
-        RCUTILS_LOG_ERROR_NAMED(
-          "rclcpp",
-          "Couldn't add waitable to wait set: %s", rcl_get_error_string().str);
-        return false;
-      }
+    for (const std::shared_ptr<Waitable> & waitable : waitable_handles_) {
+      waitable->add_to_wait_set(wait_set);
     }
     return true;
   }
@@ -388,6 +370,11 @@ public:
           ++it;
           continue;
         }
+        if (!timer->call()) {
+          // timer was cancelled, skip it.
+          ++it;
+          continue;
+        }
         // Otherwise it is safe to set and return the any_exec
         any_exec.timer = timer;
         any_exec.callback_group = group;
@@ -395,7 +382,7 @@ public:
         timer_handles_.erase(it);
         return;
       }
-      // Else, the service is no longer valid, remove it and continue
+      // Else, the timer is no longer valid, remove it and continue
       it = timer_handles_.erase(it);
     }
   }
@@ -407,7 +394,7 @@ public:
   {
     auto it = waitable_handles_.begin();
     while (it != waitable_handles_.end()) {
-      auto waitable = *it;
+      std::shared_ptr<Waitable> & waitable = *it;
       if (waitable) {
         // Find the group for this handle and see if it can be serviced
         auto group = get_group_by_waitable(waitable, weak_groups_to_nodes);
@@ -437,13 +424,17 @@ public:
 
   rcl_allocator_t get_allocator() override
   {
-    return rclcpp::allocator::get_rcl_allocator<void *, VoidAlloc>(*allocator_.get());
+    if constexpr (std::is_same_v<Alloc, std::allocator<void>>) {
+      return rcl_get_default_allocator();
+    } else {
+      return rclcpp::allocator::get_rcl_allocator<void *, VoidAlloc>(*allocator_.get());
+    }
   }
 
   size_t number_of_ready_subscriptions() const override
   {
     size_t number_of_subscriptions = subscription_handles_.size();
-    for (auto waitable : waitable_handles_) {
+    for (const std::shared_ptr<Waitable> & waitable : waitable_handles_) {
       number_of_subscriptions += waitable->get_number_of_ready_subscriptions();
     }
     return number_of_subscriptions;
@@ -452,7 +443,7 @@ public:
   size_t number_of_ready_services() const override
   {
     size_t number_of_services = service_handles_.size();
-    for (auto waitable : waitable_handles_) {
+    for (const std::shared_ptr<Waitable> & waitable : waitable_handles_) {
       number_of_services += waitable->get_number_of_ready_services();
     }
     return number_of_services;
@@ -461,7 +452,7 @@ public:
   size_t number_of_ready_events() const override
   {
     size_t number_of_events = 0;
-    for (auto waitable : waitable_handles_) {
+    for (const std::shared_ptr<Waitable> & waitable : waitable_handles_) {
       number_of_events += waitable->get_number_of_ready_events();
     }
     return number_of_events;
@@ -470,7 +461,7 @@ public:
   size_t number_of_ready_clients() const override
   {
     size_t number_of_clients = client_handles_.size();
-    for (auto waitable : waitable_handles_) {
+    for (const std::shared_ptr<Waitable> & waitable : waitable_handles_) {
       number_of_clients += waitable->get_number_of_ready_clients();
     }
     return number_of_clients;
@@ -479,7 +470,7 @@ public:
   size_t number_of_guard_conditions() const override
   {
     size_t number_of_guard_conditions = guard_conditions_.size();
-    for (auto waitable : waitable_handles_) {
+    for (const std::shared_ptr<Waitable> & waitable : waitable_handles_) {
       number_of_guard_conditions += waitable->get_number_of_ready_guard_conditions();
     }
     return number_of_guard_conditions;
@@ -488,7 +479,7 @@ public:
   size_t number_of_ready_timers() const override
   {
     size_t number_of_timers = timer_handles_.size();
-    for (auto waitable : waitable_handles_) {
+    for (const std::shared_ptr<Waitable> & waitable : waitable_handles_) {
       number_of_timers += waitable->get_number_of_ready_timers();
     }
     return number_of_timers;
@@ -504,7 +495,7 @@ private:
   using VectorRebind =
     std::vector<T, typename std::allocator_traits<Alloc>::template rebind_alloc<T>>;
 
-  VectorRebind<const rcl_guard_condition_t *> guard_conditions_;
+  VectorRebind<const rclcpp::GuardCondition *> guard_conditions_;
 
   VectorRebind<std::shared_ptr<const rcl_subscription_t>> subscription_handles_;
   VectorRebind<std::shared_ptr<const rcl_service_t>> service_handles_;

rclcpp/include/rclcpp/subscription.hpp

@@ -146,19 +146,19 @@ public:
     options_(options),
     message_memory_strategy_(message_memory_strategy)
   {
-    if (options.event_callbacks.deadline_callback) {
+    if (options_.event_callbacks.deadline_callback) {
       this->add_event_handler(
-        options.event_callbacks.deadline_callback,
+        options_.event_callbacks.deadline_callback,
         RCL_SUBSCRIPTION_REQUESTED_DEADLINE_MISSED);
     }
-    if (options.event_callbacks.liveliness_callback) {
+    if (options_.event_callbacks.liveliness_callback) {
       this->add_event_handler(
-        options.event_callbacks.liveliness_callback,
+        options_.event_callbacks.liveliness_callback,
         RCL_SUBSCRIPTION_LIVELINESS_CHANGED);
     }
-    if (options.event_callbacks.incompatible_qos_callback) {
+    if (options_.event_callbacks.incompatible_qos_callback) {
       this->add_event_handler(
-        options.event_callbacks.incompatible_qos_callback,
+        options_.event_callbacks.incompatible_qos_callback,
         RCL_SUBSCRIPTION_REQUESTED_INCOMPATIBLE_QOS);
     } else if (options_.use_default_callbacks) {
       // Register default callback when not specified
@@ -172,40 +172,50 @@ public:
         // pass
       }
     }
-    if (options.event_callbacks.message_lost_callback) {
+    if (options_.event_callbacks.message_lost_callback) {
       this->add_event_handler(
-        options.event_callbacks.message_lost_callback,
+        options_.event_callbacks.message_lost_callback,
         RCL_SUBSCRIPTION_MESSAGE_LOST);
     }
 
     // Setup intra process publishing if requested.
-    if (rclcpp::detail::resolve_use_intra_process(options, *node_base)) {
+    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.
       auto qos_profile = get_actual_qos();
       if (qos_profile.history() != rclcpp::HistoryPolicy::KeepLast) {
         throw std::invalid_argument(
-                "intraprocess communication allowed only with keep last history qos policy");
+                "intraprocess communication on topic '" + topic_name +
+                "' allowed only with keep last history qos policy");
       }
       if (qos_profile.depth() == 0) {
         throw std::invalid_argument(
-                "intraprocess communication is not allowed with 0 depth qos policy");
+                "intraprocess communication on topic '" + topic_name +
+                "' is not allowed with 0 depth qos policy");
       }
       if (qos_profile.durability() != rclcpp::DurabilityPolicy::Volatile) {
         throw std::invalid_argument(
                 "intraprocess communication allowed only with volatile durability");
       }
 
+      using SubscriptionIntraProcessT = rclcpp::experimental::SubscriptionIntraProcess<
+        MessageT,
+        SubscribedType,
+        SubscribedTypeAllocator,
+        SubscribedTypeDeleter,
+        ROSMessageT,
+        AllocatorT>;
+
       // First create a SubscriptionIntraProcess which will be given to the intra-process manager.
       auto context = node_base->get_context();
       subscription_intra_process_ = std::make_shared<SubscriptionIntraProcessT>(
         callback,
-        options.get_allocator(),
+        options_.get_allocator(),
         context,
         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));
+        resolve_intra_process_buffer_type(options_.intra_process_buffer_type, callback));
       TRACEPOINT(
         rclcpp_subscription_init,
         static_cast<const void *>(get_subscription_handle().get()),
@@ -276,7 +286,7 @@ public:
 
   /// Take the next message from the inter-process subscription.
   /**
-   * This verison takes a SubscribedType which is different frmo the
+   * This version takes a SubscribedType which is different from the
    * ROSMessageType when a rclcpp::TypeAdapter is in used.
    *
    * \sa take(ROSMessageType &, rclcpp::MessageInfo &)
@@ -355,11 +365,31 @@ public:
     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<ROSMessageType *>(loaned_message);
     // message is loaned, so we have to make sure that the deleter does not deallocate the message
     auto sptr = std::shared_ptr<ROSMessageType>(
       typed_message, [](ROSMessageType * 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.
@@ -404,13 +434,6 @@ private:
 
   /// Component which computes and publishes topic statistics for this subscriber
   SubscriptionTopicStatisticsSharedPtr subscription_topic_statistics_{nullptr};
-
-  using SubscriptionIntraProcessT = rclcpp::experimental::SubscriptionIntraProcess<
-    ROSMessageType,
-    AllocatorT,
-    ROSMessageTypeDeleter,
-    MessageT>;
-  std::shared_ptr<SubscriptionIntraProcessT> subscription_intra_process_;
 };
 
 }  // namespace rclcpp

rclcpp/include/rclcpp/subscription_base.hpp

@@ -17,16 +17,20 @@
 
 #include <atomic>
 #include <memory>
+#include <mutex>
 #include <string>
 #include <unordered_map>
 #include <vector>
 #include <utility>
 
+#include "rcl/event_callback.h"
 #include "rcl/subscription.h"
 
+#include "rmw/impl/cpp/demangle.hpp"
 #include "rmw/rmw.h"
 
 #include "rclcpp/any_subscription_callback.hpp"
+#include "rclcpp/detail/cpp_callback_trampoline.hpp"
 #include "rclcpp/experimental/intra_process_manager.hpp"
 #include "rclcpp/experimental/subscription_intra_process_base.hpp"
 #include "rclcpp/macros.hpp"
@@ -35,6 +39,7 @@
 #include "rclcpp/qos.hpp"
 #include "rclcpp/qos_event.hpp"
 #include "rclcpp/serialized_message.hpp"
+#include "rclcpp/subscription_content_filter_options.hpp"
 #include "rclcpp/type_support_decl.hpp"
 #include "rclcpp/visibility_control.hpp"
 
@@ -99,15 +104,16 @@ public:
   get_subscription_handle() const;
 
   /// Get all the QoS event handlers associated with this subscription.
-  /** \return The vector of QoS event handlers. */
+  /** \return The map of QoS event handlers. */
   RCLCPP_PUBLIC
-  const std::vector<std::shared_ptr<rclcpp::QOSEventHandlerBase>> &
+  const
+  std::unordered_map<rcl_subscription_event_type_t, std::shared_ptr<rclcpp::QOSEventHandlerBase>> &
   get_event_handlers() const;
 
   /// Get the actual QoS settings, after the defaults have been determined.
   /**
    * The actual configuration applied when using RMW_QOS_POLICY_*_SYSTEM_DEFAULT
-   * can only be resolved after the creation of the publisher, and it
+   * can only be resolved after the creation of the subscription, and it
    * depends on the underlying rmw implementation.
    * If the underlying setting in use can't be represented in ROS terms,
    * it will be set to RMW_QOS_POLICY_*_UNKNOWN.
@@ -283,6 +289,243 @@ public:
   std::vector<rclcpp::NetworkFlowEndpoint>
   get_network_flow_endpoints() const;
 
+  /// Set a callback to be called when each new message is received.
+  /**
+   * The callback receives a size_t which is the number of messages received
+   * since the last time this callback was called.
+   * Normally this is 1, but can be > 1 if messages were received before any
+   * callback was set.
+   *
+   * Since this callback is called from the middleware, you should aim to make
+   * it fast and not blocking.
+   * If you need to do a lot of work or wait for some other event, you should
+   * spin it off to another thread, otherwise you risk blocking the middleware.
+   *
+   * Calling it again will clear any previously set callback.
+   *
+   * This function is thread-safe.
+   *
+   * If you want more information available in the callback, like the subscription
+   * or other information, you may use a lambda with captures or std::bind.
+   *
+   * \sa rmw_subscription_set_on_new_message_callback
+   * \sa rcl_subscription_set_on_new_message_callback
+   *
+   * \param[in] callback functor to be called when a new message is received
+   */
+  void
+  set_on_new_message_callback(std::function<void(size_t)> callback)
+  {
+    if (!callback) {
+      throw std::invalid_argument(
+              "The callback passed to set_on_new_message_callback "
+              "is not callable.");
+    }
+
+    auto new_callback =
+      [callback, this](size_t number_of_messages) {
+        try {
+          callback(number_of_messages);
+        } catch (const std::exception & exception) {
+          RCLCPP_ERROR_STREAM(
+            node_logger_,
+            "rclcpp::SubscriptionBase@" << this <<
+              " caught " << rmw::impl::cpp::demangle(exception) <<
+              " exception in user-provided callback for the 'on new message' callback: " <<
+              exception.what());
+        } catch (...) {
+          RCLCPP_ERROR_STREAM(
+            node_logger_,
+            "rclcpp::SubscriptionBase@" << this <<
+              " caught unhandled exception in user-provided callback " <<
+              "for the 'on new message' callback");
+        }
+      };
+
+    std::lock_guard<std::recursive_mutex> lock(callback_mutex_);
+
+    // Set it temporarily to the new callback, while we replace the old one.
+    // This two-step setting, prevents a gap where the old std::function has
+    // been replaced but the middleware hasn't been told about the new one yet.
+    set_on_new_message_callback(
+      rclcpp::detail::cpp_callback_trampoline<const void *, size_t>,
+      static_cast<const void *>(&new_callback));
+
+    // Store the std::function to keep it in scope, also overwrites the existing one.
+    on_new_message_callback_ = new_callback;
+
+    // Set it again, now using the permanent storage.
+    set_on_new_message_callback(
+      rclcpp::detail::cpp_callback_trampoline<const void *, size_t>,
+      static_cast<const void *>(&on_new_message_callback_));
+  }
+
+  /// Unset the callback registered for new messages, if any.
+  void
+  clear_on_new_message_callback()
+  {
+    std::lock_guard<std::recursive_mutex> lock(callback_mutex_);
+
+    if (on_new_message_callback_) {
+      set_on_new_message_callback(nullptr, nullptr);
+      on_new_message_callback_ = nullptr;
+    }
+  }
+
+  /// Set a callback to be called when each new intra-process message is received.
+  /**
+   * The callback receives a size_t which is the number of messages received
+   * since the last time this callback was called.
+   * Normally this is 1, but can be > 1 if messages were received before any
+   * callback was set.
+   *
+   * Calling it again will clear any previously set callback.
+   *
+   * This function is thread-safe.
+   *
+   * If you want more information available in the callback, like the subscription
+   * or other information, you may use a lambda with captures or std::bind.
+   *
+   * \sa rclcpp::SubscriptionIntraProcessBase::set_on_ready_callback
+   *
+   * \param[in] callback functor to be called when a new message is received
+   */
+  void
+  set_on_new_intra_process_message_callback(std::function<void(size_t)> callback)
+  {
+    if (!use_intra_process_) {
+      RCLCPP_WARN(
+        rclcpp::get_logger("rclcpp"),
+        "Calling set_on_new_intra_process_message_callback for subscription with IPC disabled");
+      return;
+    }
+
+    if (!callback) {
+      throw std::invalid_argument(
+              "The callback passed to set_on_new_intra_process_message_callback "
+              "is not callable.");
+    }
+
+    // The on_ready_callback signature has an extra `int` argument used to disambiguate between
+    // possible different entities within a generic waitable.
+    // We hide that detail to users of this method.
+    std::function<void(size_t, int)> new_callback = std::bind(callback, std::placeholders::_1);
+    subscription_intra_process_->set_on_ready_callback(new_callback);
+  }
+
+  /// Unset the callback registered for new intra-process messages, if any.
+  void
+  clear_on_new_intra_process_message_callback()
+  {
+    if (!use_intra_process_) {
+      RCLCPP_WARN(
+        rclcpp::get_logger("rclcpp"),
+        "Calling clear_on_new_intra_process_message_callback for subscription with IPC disabled");
+      return;
+    }
+
+    subscription_intra_process_->clear_on_ready_callback();
+  }
+
+  /// Set a callback to be called when each new qos event instance occurs.
+  /**
+   * The callback receives a size_t which is the number of events that occurred
+   * since the last time this callback was called.
+   * Normally this is 1, but can be > 1 if events occurred before any
+   * callback was set.
+   *
+   * Since this callback is called from the middleware, you should aim to make
+   * it fast and not blocking.
+   * If you need to do a lot of work or wait for some other event, you should
+   * spin it off to another thread, otherwise you risk blocking the middleware.
+   *
+   * Calling it again will clear any previously set callback.
+   *
+   * An exception will be thrown if the callback is not callable.
+   *
+   * This function is thread-safe.
+   *
+   * If you want more information available in the callback, like the qos event
+   * or other information, you may use a lambda with captures or std::bind.
+   *
+   * \sa rclcpp::QOSEventHandlerBase::set_on_ready_callback
+   *
+   * \param[in] callback functor to be called when a new event occurs
+   * \param[in] event_type identifier for the qos event we want to attach the callback to
+   */
+  void
+  set_on_new_qos_event_callback(
+    std::function<void(size_t)> callback,
+    rcl_subscription_event_type_t event_type)
+  {
+    if (event_handlers_.count(event_type) == 0) {
+      RCLCPP_WARN(
+        rclcpp::get_logger("rclcpp"),
+        "Calling set_on_new_qos_event_callback for non registered subscription event_type");
+      return;
+    }
+
+    if (!callback) {
+      throw std::invalid_argument(
+              "The callback passed to set_on_new_qos_event_callback "
+              "is not callable.");
+    }
+
+    // The on_ready_callback signature has an extra `int` argument used to disambiguate between
+    // possible different entities within a generic waitable.
+    // We hide that detail to users of this method.
+    std::function<void(size_t, int)> new_callback = std::bind(callback, std::placeholders::_1);
+    event_handlers_[event_type]->set_on_ready_callback(new_callback);
+  }
+
+  /// Unset the callback registered for new qos events, if any.
+  void
+  clear_on_new_qos_event_callback(rcl_subscription_event_type_t event_type)
+  {
+    if (event_handlers_.count(event_type) == 0) {
+      RCLCPP_WARN(
+        rclcpp::get_logger("rclcpp"),
+        "Calling clear_on_new_qos_event_callback for non registered event_type");
+      return;
+    }
+
+    event_handlers_[event_type]->clear_on_ready_callback();
+  }
+
+  /// Check if content filtered topic feature of the subscription instance is enabled.
+  /**
+   * \return boolean flag indicating if the content filtered topic of this subscription is enabled.
+   */
+  RCLCPP_PUBLIC
+  bool
+  is_cft_enabled() const;
+
+  /// Set the filter expression and expression parameters for the subscription.
+  /**
+   * \param[in] filter_expression A filter expression to set.
+   *   \sa ContentFilterOptions::filter_expression
+   *   An empty string ("") will clear the content filter setting of the subscription.
+   * \param[in] expression_parameters Array of expression parameters to set.
+   *   \sa ContentFilterOptions::expression_parameters
+   * \throws RCLBadAlloc if memory cannot be allocated
+   * \throws RCLError if an unexpect error occurs
+   */
+  RCLCPP_PUBLIC
+  void
+  set_content_filter(
+    const std::string & filter_expression,
+    const std::vector<std::string> & expression_parameters = {});
+
+  /// Get the filter expression and expression parameters for the subscription.
+  /**
+   * \return rclcpp::ContentFilterOptions The content filter options to get.
+   * \throws RCLBadAlloc if memory cannot be allocated
+   * \throws RCLError if an unexpect error occurs
+   */
+  RCLCPP_PUBLIC
+  rclcpp::ContentFilterOptions
+  get_content_filter() const;
+
 protected:
   template<typename EventCallbackT>
   void
@@ -297,7 +540,7 @@ protected:
       get_subscription_handle(),
       event_type);
     qos_events_in_use_by_wait_set_.insert(std::make_pair(handler.get(), false));
-    event_handlers_.emplace_back(handler);
+    event_handlers_.insert(std::make_pair(event_type, handler));
   }
 
   RCLCPP_PUBLIC
@@ -307,17 +550,24 @@ protected:
   bool
   matches_any_intra_process_publishers(const rmw_gid_t * sender_gid) const;
 
+  RCLCPP_PUBLIC
+  void
+  set_on_new_message_callback(rcl_event_callback_t callback, const void * user_data);
+
   rclcpp::node_interfaces::NodeBaseInterface * const node_base_;
 
   std::shared_ptr<rcl_node_t> node_handle_;
   std::shared_ptr<rcl_subscription_t> subscription_handle_;
   std::shared_ptr<rcl_subscription_t> intra_process_subscription_handle_;
+  rclcpp::Logger node_logger_;
 
-  std::vector<std::shared_ptr<rclcpp::QOSEventHandlerBase>> event_handlers_;
+  std::unordered_map<rcl_subscription_event_type_t,
+    std::shared_ptr<rclcpp::QOSEventHandlerBase>> event_handlers_;
 
   bool use_intra_process_;
   IntraProcessManagerWeakPtr weak_ipm_;
   uint64_t intra_process_subscription_id_;
+  std::shared_ptr<rclcpp::experimental::SubscriptionIntraProcessBase> subscription_intra_process_;
 
 private:
   RCLCPP_DISABLE_COPY(SubscriptionBase)
@@ -329,6 +579,9 @@ private:
   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_;
+
+  std::recursive_mutex callback_mutex_;
+  std::function<void(size_t)> on_new_message_callback_{nullptr};
 };
 
 }  // namespace rclcpp

rclcpp/include/rclcpp/subscription_content_filter_options.hpp

@@ -0,0 +1,38 @@
+// Copyright 2022 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_CONTENT_FILTER_OPTIONS_HPP_
+#define RCLCPP__SUBSCRIPTION_CONTENT_FILTER_OPTIONS_HPP_
+
+#include <string>
+#include <vector>
+
+namespace rclcpp
+{
+
+/// Options to configure content filtered topic in the subscription.
+struct ContentFilterOptions
+{
+  /// Filter expression is similar to the WHERE part of an SQL clause.
+  std::string filter_expression;
+  /**
+   * Expression parameters is the tokens placeholder ‘parameters’ (i.e., "%n" tokens begin from 0)
+   * in the filter_expression. The maximum expression_parameters size is 100.
+   */
+  std::vector<std::string> expression_parameters;
+};
+
+}  // namespace rclcpp
+
+#endif  // RCLCPP__SUBSCRIPTION_CONTENT_FILTER_OPTIONS_HPP_

rclcpp/include/rclcpp/subscription_factory.hpp

@@ -26,14 +26,13 @@
 
 #include "rclcpp/any_subscription_callback.hpp"
 #include "rclcpp/get_message_type_support_handle.hpp"
-#include "rclcpp/intra_process_buffer_type.hpp"
 #include "rclcpp/node_interfaces/node_base_interface.hpp"
 #include "rclcpp/qos.hpp"
 #include "rclcpp/subscription.hpp"
 #include "rclcpp/subscription_options.hpp"
 #include "rclcpp/subscription_traits.hpp"
-#include "rclcpp/visibility_control.hpp"
 #include "rclcpp/topic_statistics/subscription_topic_statistics.hpp"
+#include "rclcpp/visibility_control.hpp"
 
 namespace rclcpp
 {

rclcpp/include/rclcpp/subscription_options.hpp

@@ -28,6 +28,7 @@
 #include "rclcpp/qos.hpp"
 #include "rclcpp/qos_event.hpp"
 #include "rclcpp/qos_overriding_options.hpp"
+#include "rclcpp/subscription_content_filter_options.hpp"
 #include "rclcpp/topic_statistics_state.hpp"
 #include "rclcpp/visibility_control.hpp"
 
@@ -81,6 +82,8 @@ struct SubscriptionOptionsBase
   TopicStatisticsOptions topic_stats_options;
 
   QosOverridingOptions qos_overriding_options;
+
+  ContentFilterOptions content_filter_options;
 };
 
 /// Structure containing optional configuration for Subscriptions.
@@ -94,7 +97,7 @@ struct SubscriptionOptionsWithAllocator : public SubscriptionOptionsBase
   /// Optional custom allocator.
   std::shared_ptr<Allocator> allocator = nullptr;
 
-  SubscriptionOptionsWithAllocator<Allocator>() {}
+  SubscriptionOptionsWithAllocator() {}
 
   /// Constructor using base class as input.
   explicit SubscriptionOptionsWithAllocator(
@@ -123,6 +126,21 @@ struct SubscriptionOptionsWithAllocator : public SubscriptionOptionsBase
       rmw_implementation_payload->modify_rmw_subscription_options(result.rmw_subscription_options);
     }
 
+    // Copy content_filter_options into rcl_subscription_options.
+    if (!content_filter_options.filter_expression.empty()) {
+      std::vector<const char *> cstrings =
+        get_c_vector_string(content_filter_options.expression_parameters);
+      rcl_ret_t ret = rcl_subscription_options_set_content_filter_options(
+        get_c_string(content_filter_options.filter_expression),
+        cstrings.size(),
+        cstrings.data(),
+        &result);
+      if (RCL_RET_OK != ret) {
+        rclcpp::exceptions::throw_from_rcl_error(
+          ret, "failed to set content_filter_options");
+      }
+    }
+
     return result;
   }
 
@@ -145,11 +163,15 @@ private:
   rcl_allocator_t
   get_rcl_allocator() const
   {
-    if (!plain_allocator_storage_) {
-      plain_allocator_storage_ =
-        std::make_shared<PlainAllocator>(*this->get_allocator());
+    if constexpr (std::is_same_v<Allocator, std::allocator<void>>) {
+      return rcl_get_default_allocator();
+    } else {
+      if (!plain_allocator_storage_) {
+        plain_allocator_storage_ =
+          std::make_shared<PlainAllocator>(*this->get_allocator());
+      }
+      return rclcpp::allocator::get_rcl_allocator<char>(*plain_allocator_storage_);
     }
-    return rclcpp::allocator::get_rcl_allocator<char>(*plain_allocator_storage_);
   }
 
   // This is a temporal workaround, to make sure that get_allocator()

rclcpp/include/rclcpp/time_source.hpp

@@ -56,6 +56,7 @@ public:
    *
    * \param node std::shared pointer to a initialized node
    * \param qos QoS that will be used when creating a `/clock` subscription.
+   * \param use_clock_thread whether to spin the attached node in a separate thread
    */
   RCLCPP_PUBLIC
   explicit TimeSource(
@@ -68,12 +69,21 @@ public:
    * An Empty TimeSource class
    *
    * \param qos QoS that will be used when creating a `/clock` subscription.
+   * \param use_clock_thread whether to spin the attached node in a separate thread.
    */
   RCLCPP_PUBLIC
   explicit TimeSource(
     const rclcpp::QoS & qos = rclcpp::ClockQoS(),
     bool use_clock_thread = true);
 
+  // The TimeSource is uncopyable
+  TimeSource(const TimeSource &) = delete;
+  TimeSource & operator=(const TimeSource &) = delete;
+
+  // The TimeSource is moveable
+  TimeSource(TimeSource &&) = default;
+  TimeSource & operator=(TimeSource &&) = default;
+
   /// Attach node to the time source.
   /**
    * \param node std::shared pointer to a initialized node
@@ -116,89 +126,33 @@ public:
   RCLCPP_PUBLIC
   void attachClock(rclcpp::Clock::SharedPtr clock);
 
-  /// Detach a clock to the time source
+  /// Detach a clock from the time source
   RCLCPP_PUBLIC
   void detachClock(rclcpp::Clock::SharedPtr clock);
 
+  /// Get whether a separate clock thread is used or not
+  RCLCPP_PUBLIC
+  bool get_use_clock_thread();
+
+  /// Set whether to use a separate clock thread or not
+  RCLCPP_PUBLIC
+  void set_use_clock_thread(bool use_clock_thread);
+
+  /// Check if the clock thread is joinable
+  RCLCPP_PUBLIC
+  bool clock_thread_is_joinable();
+
   /// TimeSource Destructor
   RCLCPP_PUBLIC
   ~TimeSource();
 
-protected:
-  // Dedicated thread for clock subscription.
-  bool use_clock_thread_;
-  std::thread clock_executor_thread_;
-
 private:
-  // Preserve the node reference
-  rclcpp::node_interfaces::NodeBaseInterface::SharedPtr node_base_;
-  rclcpp::node_interfaces::NodeTopicsInterface::SharedPtr node_topics_;
-  rclcpp::node_interfaces::NodeGraphInterface::SharedPtr node_graph_;
-  rclcpp::node_interfaces::NodeServicesInterface::SharedPtr node_services_;
-  rclcpp::node_interfaces::NodeLoggingInterface::SharedPtr node_logging_;
-  rclcpp::node_interfaces::NodeClockInterface::SharedPtr node_clock_;
-  rclcpp::node_interfaces::NodeParametersInterface::SharedPtr node_parameters_;
+  class NodeState;
+  std::shared_ptr<NodeState> node_state_;
 
-  // Store (and update on node attach) logger for logging.
-  Logger logger_;
-
-  // QoS of the clock subscription.
-  rclcpp::QoS qos_;
-
-  // The subscription for the clock callback
-  using MessageT = rosgraph_msgs::msg::Clock;
-  using Alloc = std::allocator<void>;
-  using SubscriptionT = rclcpp::Subscription<MessageT, Alloc>;
-  std::shared_ptr<SubscriptionT> clock_subscription_{nullptr};
-  std::mutex clock_sub_lock_;
-  rclcpp::CallbackGroup::SharedPtr clock_callback_group_;
-  rclcpp::executors::SingleThreadedExecutor::SharedPtr clock_executor_;
-  std::promise<void> cancel_clock_executor_promise_;
-
-  // The clock callback itself
-  void clock_cb(std::shared_ptr<const rosgraph_msgs::msg::Clock> msg);
-
-  // Create the subscription for the clock topic
-  void create_clock_sub();
-
-  // Destroy the subscription for the clock topic
-  void destroy_clock_sub();
-
-  // Parameter Event subscription
-  using ParamMessageT = rcl_interfaces::msg::ParameterEvent;
-  using ParamSubscriptionT = rclcpp::Subscription<ParamMessageT, Alloc>;
-  std::shared_ptr<ParamSubscriptionT> parameter_subscription_;
-
-  // Callback for parameter updates
-  void on_parameter_event(std::shared_ptr<const rcl_interfaces::msg::ParameterEvent> event);
-
-  // An enum to hold the parameter state
-  enum UseSimTimeParameterState {UNSET, SET_TRUE, SET_FALSE};
-  UseSimTimeParameterState parameter_state_;
-
-  // An internal method to use in the clock callback that iterates and enables all clocks
-  void enable_ros_time();
-  // An internal method to use in the clock callback that iterates and disables all clocks
-  void disable_ros_time();
-
-  // Internal helper functions used inside iterators
-  static void set_clock(
-    const builtin_interfaces::msg::Time::SharedPtr msg,
-    bool set_ros_time_enabled,
-    rclcpp::Clock::SharedPtr clock);
-
-  // Local storage of validity of ROS time
-  // This is needed when new clocks are added.
-  bool ros_time_active_{false};
-  // Last set message to be passed to newly registered clocks
-  std::shared_ptr<const rosgraph_msgs::msg::Clock> last_msg_set_;
-
-  // A lock to protect iterating the associated_clocks_ field.
-  std::mutex clock_list_lock_;
-  // A vector to store references to associated clocks.
-  std::vector<rclcpp::Clock::SharedPtr> associated_clocks_;
-  // A handler for the use_sim_time parameter callback.
-  rclcpp::node_interfaces::OnSetParametersCallbackHandle::SharedPtr sim_time_cb_handler_{nullptr};
+  // Preserve the arguments received by the constructor for reuse at runtime
+  bool constructed_use_clock_thread_;
+  rclcpp::QoS constructed_qos_;
 };
 
 }  // namespace rclcpp

rclcpp/include/rclcpp/timer.hpp

@@ -91,6 +91,17 @@ public:
   void
   reset();
 
+  /// Indicate that we're about to execute the callback.
+  /**
+   * The multithreaded executor takes advantage of this to avoid scheduling
+   * the callback multiple times.
+   *
+   * \return `true` if the callback should be executed, `false` if the timer was canceled.
+   */
+  RCLCPP_PUBLIC
+  virtual bool
+  call() = 0;
+
   /// Call the callback function when the timer signal is emitted.
   RCLCPP_PUBLIC
   virtual void
@@ -102,7 +113,8 @@ public:
 
   /// 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
+   * or std::chrono::nanoseconds::max() if the timer is canceled.
    * \throws std::runtime_error if the rcl_timer_get_time_until_next_call returns a failure
    */
   RCLCPP_PUBLIC
@@ -192,19 +204,28 @@ public:
   }
 
   /**
-   * \sa rclcpp::TimerBase::execute_callback
-   * \throws std::runtime_error if it failed to notify timer that callback occurred
+   * \sa rclcpp::TimerBase::call
+   * \throws std::runtime_error if it failed to notify timer that callback will occurr
    */
-  void
-  execute_callback() override
+  bool
+  call() override
   {
     rcl_ret_t ret = rcl_timer_call(timer_handle_.get());
     if (ret == RCL_RET_TIMER_CANCELED) {
-      return;
+      return false;
     }
     if (ret != RCL_RET_OK) {
       throw std::runtime_error("Failed to notify timer that callback occurred");
     }
+    return true;
+  }
+
+  /**
+   * \sa rclcpp::TimerBase::execute_callback
+   */
+  void
+  execute_callback() override
+  {
     TRACEPOINT(callback_start, static_cast<const void *>(&callback_), false);
     execute_callback_delegate<>();
     TRACEPOINT(callback_end, static_cast<const void *>(&callback_));

rclcpp/include/rclcpp/utilities.hpp

@@ -42,6 +42,20 @@ std::string to_string(T value)
 
 namespace rclcpp
 {
+
+/// Option to indicate which signal handlers rclcpp should install.
+enum class SignalHandlerOptions
+{
+  /// Install both sigint and sigterm, this is the default behavior.
+  All,
+  /// Install only a sigint handler.
+  SigInt,
+  /// Install only a sigterm handler.
+  SigTerm,
+  /// Do not install any signal handler.
+  None,
+};
+
 /// Initialize communications via the rmw implementation and set up a global signal handler.
 /**
  * Initializes the global context which is accessible via the function
@@ -50,10 +64,19 @@ namespace rclcpp
  * rclcpp::install_signal_handlers().
  *
  * \sa rclcpp::Context::init() for more details on arguments and possible exceptions
+ *
+ * \param[in] argc number of command-line arguments to parse.
+ * \param[in] argv array of command-line arguments to parse.
+ * \param[in] init_options initialization options to apply.
+ * \param[in] signal_handler_options option to indicate which signal handlers should be installed.
  */
 RCLCPP_PUBLIC
 void
-init(int argc, char const * const argv[], const InitOptions & init_options = InitOptions());
+init(
+  int argc,
+  char const * const * argv,
+  const InitOptions & init_options = InitOptions(),
+  SignalHandlerOptions signal_handler_options = SignalHandlerOptions::All);
 
 /// Install the global signal handler for rclcpp.
 /**
@@ -67,17 +90,26 @@ init(int argc, char const * const argv[], const InitOptions & init_options = Ini
  *
  * This function is thread-safe.
  *
+ * \param[in] signal_handler_options option to indicate which signal handlers should be installed.
  * \return true if signal handler was installed by this function, false if already installed.
  */
 RCLCPP_PUBLIC
 bool
-install_signal_handlers();
+install_signal_handlers(SignalHandlerOptions signal_handler_options = SignalHandlerOptions::All);
 
 /// Return true if the signal handlers are installed, otherwise false.
 RCLCPP_PUBLIC
 bool
 signal_handlers_installed();
 
+/// Get the current signal handler options.
+/**
+ * If no signal handler is installed, SignalHandlerOptions::None is returned.
+ */
+RCLCPP_PUBLIC
+SignalHandlerOptions
+get_current_signal_handler_options();
+
 /// Uninstall the global signal handler for rclcpp.
 /**
  * This function does not necessarily need to be called, but can be used to
@@ -107,7 +139,7 @@ RCLCPP_PUBLIC
 std::vector<std::string>
 init_and_remove_ros_arguments(
   int argc,
-  char const * const argv[],
+  char const * const * argv,
   const InitOptions & init_options = InitOptions());
 
 /// Remove ROS-specific arguments from argument vector.
@@ -125,7 +157,7 @@ init_and_remove_ros_arguments(
  */
 RCLCPP_PUBLIC
 std::vector<std::string>
-remove_ros_arguments(int argc, char const * const argv[]);
+remove_ros_arguments(int argc, char const * const * argv);
 
 /// Check rclcpp's status.
 /**
@@ -289,6 +321,15 @@ RCLCPP_PUBLIC
 const char *
 get_c_string(const std::string & string_in);
 
+/// Return the std::vector of C string from the given std::vector<std::string>.
+/**
+ * \param[in] strings_in is a std::vector of std::string
+ * \return the std::vector of C string from the std::vector<std::string>
+ */
+RCLCPP_PUBLIC
+std::vector<const char *>
+get_c_vector_string(const std::vector<std::string> & strings_in);
+
 }  // namespace rclcpp
 
 #endif  // RCLCPP__UTILITIES_HPP_

rclcpp/include/rclcpp/wait_for_message.hpp

@@ -0,0 +1,107 @@
+// 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 <future>
+#include <memory>
+#include <string>
+
+#include "rcpputils/scope_exit.hpp"
+
+#include "rclcpp/node.hpp"
+#include "rclcpp/visibility_control.hpp"
+#include "rclcpp/wait_set.hpp"
+#include "rclcpp/qos.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_handle = context->add_on_shutdown_callback(
+    [weak_gc = std::weak_ptr<rclcpp::GuardCondition>{gc}]() {
+      auto strong_gc = weak_gc.lock();
+      if (strong_gc) {
+        strong_gc->trigger();
+      }
+    });
+
+  rclcpp::WaitSet wait_set({}, {}, {}, {}, {}, {}, context);
+  wait_set.add_subscription(subscription);
+  RCPPUTILS_SCOPE_EXIT(wait_set.remove_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.
+ * \param[in] qos parameter specifying QoS settings for the subscription.
+ * \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),
+  const rclcpp::QoS & qos = rclcpp::SystemDefaultsQoS())
+{
+  auto sub = node->create_subscription<MsgT>(topic, qos, [](const std::shared_ptr<const 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_

rclcpp/include/rclcpp/wait_set_policies/detail/storage_policy_common.hpp

@@ -383,10 +383,7 @@ protected:
         continue;
       }
       rclcpp::Waitable & waitable = *waitable_ptr_pair.second;
-      bool successful = waitable.add_to_wait_set(&rcl_wait_set_);
-      if (!successful) {
-        throw std::runtime_error("waitable unexpectedly failed to be added to wait set");
-      }
+      waitable.add_to_wait_set(&rcl_wait_set_);
     }
   }
 

rclcpp/include/rclcpp/wait_set_policies/detail/write_preferring_read_write_lock.hpp

@@ -191,7 +191,7 @@ protected:
 
     WritePreferringReadWriteLock & parent_lock_;
 
-    friend WritePreferringReadWriteLock;
+    friend class WritePreferringReadWriteLock;
   };
 
   /// Write mutex for the WritePreferringReadWriteLock.
@@ -212,7 +212,7 @@ protected:
 
     WritePreferringReadWriteLock & parent_lock_;
 
-    friend WritePreferringReadWriteLock;
+    friend class WritePreferringReadWriteLock;
   };
 
   /// Return read mutex which can be used with standard constructs like std::lock_guard.

rclcpp/include/rclcpp/wait_set_policies/sequential_synchronization.hpp

@@ -203,7 +203,7 @@ protected:
     std::shared_ptr<rclcpp::Waitable> && waitable,
     std::shared_ptr<void> && associated_entity,
     std::function<
-      void(std::shared_ptr<rclcpp::Waitable>&&, std::shared_ptr<void>&&)
+      void(std::shared_ptr<rclcpp::Waitable>&&, std::shared_ptr<void> &&)
     > add_waitable_function)
   {
     // Explicitly no thread synchronization.

rclcpp/include/rclcpp/wait_set_policies/thread_safe_synchronization.hpp

@@ -216,7 +216,7 @@ protected:
     std::shared_ptr<rclcpp::Waitable> && waitable,
     std::shared_ptr<void> && associated_entity,
     std::function<
-      void(std::shared_ptr<rclcpp::Waitable>&&, std::shared_ptr<void>&&)
+      void(std::shared_ptr<rclcpp::Waitable>&&, std::shared_ptr<void> &&)
     > add_waitable_function)
   {
     using rclcpp::wait_set_policies::detail::WritePreferringReadWriteLock;

rclcpp/include/rclcpp/wait_set_template.hpp

@@ -20,13 +20,13 @@
 #include <utility>
 
 #include "rcl/wait.h"
+#include "rcpputils/scope_exit.hpp"
 
 #include "rclcpp/client.hpp"
 #include "rclcpp/context.hpp"
 #include "rclcpp/contexts/default_context.hpp"
 #include "rclcpp/guard_condition.hpp"
 #include "rclcpp/macros.hpp"
-#include "rclcpp/scope_exit.hpp"
 #include "rclcpp/service.hpp"
 #include "rclcpp/subscription_base.hpp"
 #include "rclcpp/subscription_wait_set_mask.hpp"
@@ -155,7 +155,8 @@ public:
           this->storage_add_subscription(std::move(local_subscription));
         }
         if (mask.include_events) {
-          for (auto event : inner_subscription->get_event_handlers()) {
+          for (auto key_event_pair : inner_subscription->get_event_handlers()) {
+            auto event = key_event_pair.second;
             auto local_subscription = inner_subscription;
             bool already_in_use =
             local_subscription->exchange_in_use_by_wait_set_state(event.get(), true);
@@ -225,7 +226,8 @@ public:
           this->storage_remove_subscription(std::move(local_subscription));
         }
         if (mask.include_events) {
-          for (auto event : inner_subscription->get_event_handlers()) {
+          for (auto key_event_pair : inner_subscription->get_event_handlers()) {
+            auto event = key_event_pair.second;
             auto local_subscription = inner_subscription;
             local_subscription->exchange_in_use_by_wait_set_state(event.get(), false);
             this->storage_remove_waitable(std::move(event));
@@ -657,7 +659,7 @@ public:
 
     // ensure the ownership of the entities in the wait set is shared for the duration of wait
     this->storage_acquire_ownerships();
-    RCLCPP_SCOPE_EXIT({this->storage_release_ownerships();});
+    RCPPUTILS_SCOPE_EXIT({this->storage_release_ownerships();});
 
     // this method comes from the SynchronizationPolicy
     return this->template sync_wait<WaitResult<WaitSetTemplate>>(

rclcpp/include/rclcpp/waitable.hpp

@@ -16,6 +16,7 @@
 #define RCLCPP__WAITABLE_HPP_
 
 #include <atomic>
+#include <functional>
 #include <memory>
 
 #include "rclcpp/macros.hpp"
@@ -103,12 +104,11 @@ public:
   /// Add the Waitable to a wait set.
   /**
    * \param[in] wait_set A handle to the wait set to add the Waitable to.
-   * \return `true` if the Waitable is added successfully, `false` otherwise.
    * \throws rclcpp::execptions::RCLError from rcl_wait_set_add_*()
    */
   RCLCPP_PUBLIC
   virtual
-  bool
+  void
   add_to_wait_set(rcl_wait_set_t * wait_set) = 0;
 
   /// Check if the Waitable is ready.
@@ -145,8 +145,7 @@ public:
    * ```cpp
    * // ... create a wait set and a Waitable
    * // Add the Waitable to the wait set
-   * bool add_ret = waitable.add_to_wait_set(wait_set);
-   * // ... error handling
+   * waitable.add_to_wait_set(wait_set);
    * // Wait
    * rcl_ret_t wait_ret = rcl_wait(wait_set);
    * // ... error handling
@@ -161,6 +160,24 @@ public:
   std::shared_ptr<void>
   take_data() = 0;
 
+  /// Take the data so that it can be consumed with `execute`.
+  /**
+   * This function allows to specify an entity ID to take the data from.
+   * Entity IDs are identifiers that can be defined by waitable-derived
+   * classes that are composed of several distinct entities.
+   * The main use-case is in conjunction with the listener APIs.
+   *
+   * \param[in] id the id of the entity from which to take
+   * \returns the type-erased data taken from entity specified
+   *
+   * \sa rclcpp::Waitable::take_data
+   * \sa rclcpp::Waitable::set_on_ready_callback
+   */
+  RCLCPP_PUBLIC
+  virtual
+  std::shared_ptr<void>
+  take_data_by_entity_id(size_t id);
+
   /// Execute data that is passed in.
   /**
    * Before calling this method, the Waitable should be added to a wait set,
@@ -172,8 +189,7 @@ public:
    * ```cpp
    * // ... create a wait set and a Waitable
    * // Add the Waitable to the wait set
-   * bool add_ret = waitable.add_to_wait_set(wait_set);
-   * // ... error handling
+   * waitable.add_to_wait_set(wait_set);
    * // Wait
    * rcl_ret_t wait_ret = rcl_wait(wait_set);
    * // ... error handling
@@ -203,6 +219,45 @@ public:
   bool
   exchange_in_use_by_wait_set_state(bool in_use_state);
 
+  /// Set a callback to be called whenever the waitable becomes ready.
+  /**
+   * The callback receives a size_t which is the number of times the waitable was ready
+   * since the last time this callback was called.
+   * Normally this is 1, but can be > 1 if waitable was triggered before any
+   * callback was set.
+   *
+   * The callback also receives an int identifier argument.
+   * This is needed because a Waitable may be composed of several distinct entities,
+   * such as subscriptions, services, etc.
+   * The application should provide a generic callback function that will be then
+   * forwarded by the waitable to all of its entities.
+   * Before forwarding, a different value for the identifier argument will be
+   * bond to the function.
+   * This implies that the provided callback can use the identifier to behave
+   * differently depending on which entity triggered the waitable to become ready.
+   *
+   * Note: this function must be overridden with a proper implementation
+   * by the custom classes who inherit from rclcpp::Waitable if they want to use it.
+   *
+   * \sa rclcpp::Waitable::clear_on_ready_callback
+   *
+   * \param[in] callback functor to be called when the waitable becomes ready
+   */
+  RCLCPP_PUBLIC
+  virtual
+  void
+  set_on_ready_callback(std::function<void(size_t, int)> callback);
+
+  /// Unset any callback registered via set_on_ready_callback.
+  /**
+   * Note: this function must be overridden with a proper implementation
+   * by the custom classes who inherit from rclcpp::Waitable if they want to use it.
+   */
+  RCLCPP_PUBLIC
+  virtual
+  void
+  clear_on_ready_callback();
+
 private:
   std::atomic<bool> in_use_by_wait_set_{false};
 };  // class Waitable

rclcpp/package.xml

@@ -2,15 +2,17 @@
 <?xml-model href="http://download.ros.org/schema/package_format2.xsd" schematypens="http://www.w3.org/2001/XMLSchema"?>
 <package format="2">
   <name>rclcpp</name>
-  <version>11.0.0</version>
+  <version>16.0.18</version>
   <description>The ROS client library in C++.</description>
   <maintainer email="ivanpauno@ekumenlabs.com">Ivan Paunovic</maintainer>
-  <maintainer email="mabel@openrobotics.org">Mabel Zhang</maintainer>
+  <maintainer email="jacob@openrobotics.org">Jacob Perron</maintainer>
   <maintainer email="william@openrobotics.org">William Woodall</maintainer>
   <license>Apache License 2.0</license>
   <author email="dthomas@openrobotics.org">Dirk Thomas</author>
 
   <buildtool_depend>ament_cmake_ros</buildtool_depend>
+  <buildtool_depend>ament_cmake_gen_version_h</buildtool_depend>
+  <buildtool_depend>python3</buildtool_depend>
 
   <build_depend>ament_index_cpp</build_depend>
   <build_depend>builtin_interfaces</build_depend>
@@ -37,6 +39,7 @@
   <depend>tracetools</depend>
 
   <test_depend>ament_cmake_gmock</test_depend>
+  <test_depend>ament_cmake_google_benchmark</test_depend>
   <test_depend>ament_cmake_gtest</test_depend>
   <test_depend>ament_lint_auto</test_depend>
   <test_depend>ament_lint_common</test_depend>

rclcpp/resource/logging.hpp.em

@@ -125,8 +125,7 @@ def get_rclcpp_suffix_from_features(features):
 ) \
   do { \
     static_assert( \
-      ::std::is_same<typename std::remove_cv<typename std::remove_reference<decltype(logger)>::type>::type, \
-      typename ::rclcpp::Logger>::value, \
+      ::std::is_convertible_v<decltype(logger), ::rclcpp::Logger>, \
       "First argument to logging macros must be an rclcpp::Logger"); \
 @[ if 'throttle' in feature_combination]@ \
     auto get_time_point = [&c=clock](rcutils_time_point_value_t * time_point) -> rcutils_ret_t { \
@@ -141,19 +140,19 @@ def get_rclcpp_suffix_from_features(features):
     }; \
 @[ end if] \
 @[ if 'stream' in feature_combination]@
-    std::stringstream ss; \
-    ss << @(stream_arg); \
+    std::stringstream rclcpp_stream_ss_; \
+    rclcpp_stream_ss_ << @(stream_arg); \
 @[ end if]@
     RCUTILS_LOG_@(severity)@(get_suffix_from_features(feature_combination))_NAMED( \
 @{params = ['get_time_point' if p == 'clock' and 'throttle' in feature_combination else p for p in params]}@
 @[ if params]@
 @(''.join(['      ' + p + ', \\\n' for p in params if p != stream_arg]))@
 @[ end if]@
-      logger.get_name(), \
+      (logger).get_name(), \
 @[ if 'stream' not in feature_combination]@
       __VA_ARGS__); \
 @[ else]@
-      "%s", ss.str().c_str()); \
+      "%s", rclcpp_stream_ss_.str().c_str()); \
 @[ end if]@
   } while (0)
 

rclcpp/src/rclcpp/callback_group.cpp

@@ -12,9 +12,19 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-#include "rclcpp/callback_group.hpp"
+#include <algorithm>
+#include <atomic>
+#include <functional>
+#include <memory>
+#include <mutex>
+#include <stdexcept>
 
-#include <vector>
+#include "rclcpp/callback_group.hpp"
+#include "rclcpp/client.hpp"
+#include "rclcpp/service.hpp"
+#include "rclcpp/subscription_base.hpp"
+#include "rclcpp/timer.hpp"
+#include "rclcpp/waitable.hpp"
 
 using rclcpp::CallbackGroup;
 using rclcpp::CallbackGroupType;
@@ -27,6 +37,10 @@ CallbackGroup::CallbackGroup(
   automatically_add_to_executor_with_node_(automatically_add_to_executor_with_node)
 {}
 
+CallbackGroup::~CallbackGroup()
+{
+  trigger_notify_guard_condition();
+}
 
 std::atomic_bool &
 CallbackGroup::can_be_taken_from()
@@ -40,6 +54,51 @@ CallbackGroup::type() const
   return type_;
 }
 
+void CallbackGroup::collect_all_ptrs(
+  std::function<void(const rclcpp::SubscriptionBase::SharedPtr &)> sub_func,
+  std::function<void(const rclcpp::ServiceBase::SharedPtr &)> service_func,
+  std::function<void(const rclcpp::ClientBase::SharedPtr &)> client_func,
+  std::function<void(const rclcpp::TimerBase::SharedPtr &)> timer_func,
+  std::function<void(const rclcpp::Waitable::SharedPtr &)> waitable_func) const
+{
+  std::lock_guard<std::mutex> lock(mutex_);
+
+  for (const rclcpp::SubscriptionBase::WeakPtr & weak_ptr : subscription_ptrs_) {
+    rclcpp::SubscriptionBase::SharedPtr ref_ptr = weak_ptr.lock();
+    if (ref_ptr) {
+      sub_func(ref_ptr);
+    }
+  }
+
+  for (const rclcpp::ServiceBase::WeakPtr & weak_ptr : service_ptrs_) {
+    rclcpp::ServiceBase::SharedPtr ref_ptr = weak_ptr.lock();
+    if (ref_ptr) {
+      service_func(ref_ptr);
+    }
+  }
+
+  for (const rclcpp::ClientBase::WeakPtr & weak_ptr : client_ptrs_) {
+    rclcpp::ClientBase::SharedPtr ref_ptr = weak_ptr.lock();
+    if (ref_ptr) {
+      client_func(ref_ptr);
+    }
+  }
+
+  for (const rclcpp::TimerBase::WeakPtr & weak_ptr : timer_ptrs_) {
+    rclcpp::TimerBase::SharedPtr ref_ptr = weak_ptr.lock();
+    if (ref_ptr) {
+      timer_func(ref_ptr);
+    }
+  }
+
+  for (const rclcpp::Waitable::WeakPtr & weak_ptr : waitable_ptrs_) {
+    rclcpp::Waitable::SharedPtr ref_ptr = weak_ptr.lock();
+    if (ref_ptr) {
+      waitable_func(ref_ptr);
+    }
+  }
+}
+
 std::atomic_bool &
 CallbackGroup::get_associated_with_executor_atomic()
 {
@@ -52,6 +111,33 @@ CallbackGroup::automatically_add_to_executor_with_node() const
   return automatically_add_to_executor_with_node_;
 }
 
+rclcpp::GuardCondition::SharedPtr
+CallbackGroup::get_notify_guard_condition(const rclcpp::Context::SharedPtr context_ptr)
+{
+  std::lock_guard<std::recursive_mutex> lock(notify_guard_condition_mutex_);
+  if (notify_guard_condition_ && context_ptr != notify_guard_condition_->get_context()) {
+    if (associated_with_executor_) {
+      trigger_notify_guard_condition();
+    }
+    notify_guard_condition_ = nullptr;
+  }
+
+  if (!notify_guard_condition_) {
+    notify_guard_condition_ = std::make_shared<rclcpp::GuardCondition>(context_ptr);
+  }
+
+  return notify_guard_condition_;
+}
+
+void
+CallbackGroup::trigger_notify_guard_condition()
+{
+  std::lock_guard<std::recursive_mutex> lock(notify_guard_condition_mutex_);
+  if (notify_guard_condition_) {
+    notify_guard_condition_->trigger();
+  }
+}
+
 void
 CallbackGroup::add_subscription(
   const rclcpp::SubscriptionBase::SharedPtr subscription_ptr)

rclcpp/src/rclcpp/client.cpp

@@ -38,7 +38,8 @@ ClientBase::ClientBase(
   rclcpp::node_interfaces::NodeGraphInterface::SharedPtr node_graph)
 : node_graph_(node_graph),
   node_handle_(node_base->get_shared_rcl_node_handle()),
-  context_(node_base->get_context())
+  context_(node_base->get_context()),
+  node_logger_(rclcpp::get_node_logger(node_handle_.get()))
 {
   std::weak_ptr<rcl_node_t> weak_node_handle(node_handle_);
   rcl_client_t * new_rcl_client = new rcl_client_t;
@@ -66,6 +67,7 @@ ClientBase::ClientBase(
 
 ClientBase::~ClientBase()
 {
+  clear_on_new_response_callback();
   // Make sure the client handle is destructed as early as possible and before the node handle
   client_handle_.reset();
 }
@@ -198,3 +200,55 @@ ClientBase::exchange_in_use_by_wait_set_state(bool in_use_state)
 {
   return in_use_by_wait_set_.exchange(in_use_state);
 }
+
+rclcpp::QoS
+ClientBase::get_request_publisher_actual_qos() const
+{
+  const rmw_qos_profile_t * qos =
+    rcl_client_request_publisher_get_actual_qos(client_handle_.get());
+  if (!qos) {
+    auto msg =
+      std::string("failed to get client's request publisher qos settings: ") +
+      rcl_get_error_string().str;
+    rcl_reset_error();
+    throw std::runtime_error(msg);
+  }
+
+  rclcpp::QoS request_publisher_qos =
+    rclcpp::QoS(rclcpp::QoSInitialization::from_rmw(*qos), *qos);
+
+  return request_publisher_qos;
+}
+
+rclcpp::QoS
+ClientBase::get_response_subscription_actual_qos() const
+{
+  const rmw_qos_profile_t * qos =
+    rcl_client_response_subscription_get_actual_qos(client_handle_.get());
+  if (!qos) {
+    auto msg =
+      std::string("failed to get client's response subscription qos settings: ") +
+      rcl_get_error_string().str;
+    rcl_reset_error();
+    throw std::runtime_error(msg);
+  }
+
+  rclcpp::QoS response_subscription_qos =
+    rclcpp::QoS(rclcpp::QoSInitialization::from_rmw(*qos), *qos);
+
+  return response_subscription_qos;
+}
+
+void
+ClientBase::set_on_new_response_callback(rcl_event_callback_t callback, const void * user_data)
+{
+  rcl_ret_t ret = rcl_client_set_on_new_response_callback(
+    client_handle_.get(),
+    callback,
+    user_data);
+
+  if (RCL_RET_OK != ret) {
+    using rclcpp::exceptions::throw_from_rcl_error;
+    throw_from_rcl_error(ret, "failed to set the on new response callback for client");
+  }
+}