Add Interfaces for reporting of error and warning messages from HW

doc/index.rst

@@ -32,4 +32,5 @@ Concepts
    Controller Manager <../controller_manager/doc/userdoc.rst>
    Controller Chaining / Cascade Control <../controller_manager/doc/controller_chaining.rst>
    Hardware Components <../hardware_interface/doc/hardware_components_userdoc.rst>
+   Hardware Components <../hardware_interface/doc/error_and_warning_interfaces_userdoc.rst>
    Mock Components <../hardware_interface/doc/mock_components_userdoc.rst>

hardware_interface/CMakeLists.txt

@@ -76,6 +76,15 @@ if(BUILD_TESTING)
 
   ament_add_gmock(test_component_interfaces test/test_component_interfaces.cpp)
   target_link_libraries(test_component_interfaces hardware_interface)
+  ament_target_dependencies(test_component_interfaces ros2_control_test_assets)
+
+  ament_add_gmock(test_component_interfaces_custom_export test/test_component_interfaces_custom_export.cpp)
+  target_link_libraries(test_component_interfaces_custom_export hardware_interface)
+  ament_target_dependencies(test_component_interfaces_custom_export ros2_control_test_assets)
+
+  ament_add_gmock(test_error_warning_codes test/test_error_warning_codes.cpp)
+  target_link_libraries(test_error_warning_codes hardware_interface)
+  ament_target_dependencies(test_error_warning_codes ros2_control_test_assets)
 
   ament_add_gmock(test_component_parser test/test_component_parser.cpp)
   target_link_libraries(test_component_parser hardware_interface)

hardware_interface/doc/error_and_warning_interfaces_userdoc.rst

@@ -0,0 +1,28 @@
+:github_url: https://github.com/ros-controls/ros2_control/blob/{REPOS_FILE_BRANCH}/hardware_interface/doc/error_and_warning_interfaces_userdoc.rst
+
+.. _error_and_warning_interfaces_userdoc:
+
+Error and Warning Interfaces
+============================
+
+By default we now create the following error and warning interfaces:
+
++-----------------+--------------+----------------------------------------------------------------------------------------------------------------------+
+| Type            | Datatype     | Description                                                                                                          |
++=================+====================+================================================================================================================+
+| Emergency Stop  | Bool               | Used for signaling that hardwares emergency stop is active. Only for Actuator and System.                      |
++-----------------+--------------------+----------------------------------------------------------------------------------------------------------------+
++-----------------+--------------------+----------------------------------------------------------------------------------------------------------------+
+| Error Code      | array<uint8_t, 32> | Used for sending 32 error codes (uint8_t) at the same time.                                                    |
++-----------------+--------------------+----------------------------------------------------------------------------------------------------------------+
+| Error Message   | array<string, 32>  | Used for sending 32 error messages where the message at position x corresponds to error code at position x.    |
++-----------------+--------------------+----------------------------------------------------------------------------------------------------------------+
++-----------------+--------------------+----------------------------------------------------------------------------------------------------------------+
+| Warning Code    | array<int8_t, 32>  | Used for sending 32 Warning codes (int8_t) at the same time.                                                   |
++-----------------+--------------------+----------------------------------------------------------------------------------------------------------------+
+| Warning Message | array<string, 32>  | Used for sending 32 warning messages where the message at position x corresponds to warning code at position x.|
++-----------------+--------------------+----------------------------------------------------------------------------------------------------------------+
+
+The error and warning interfaces are created as ``StateInterfaces`` and are stored inside the Actuator-, Sensor- or SystemInterface. They can be accessed via getter and setter methods. E.g. if you want to get/set the emergency stop signal you can do so with the ``get_emergency_stop()`` or ``set_emergency_stop(const bool & emergency_stop)`` methods. For the error and warning signals similar getters and setters exist.
+
+Note: The SensorInterface does not have a Emergency Stop interface.

hardware_interface/include/hardware_interface/actuator.hpp

@@ -65,10 +65,10 @@ class Actuator final
   const rclcpp_lifecycle::State & error();
 
   HARDWARE_INTERFACE_PUBLIC
-  std::vector<StateInterface> export_state_interfaces();
+  std::vector<std::shared_ptr<StateInterface>> export_state_interfaces();
 
   HARDWARE_INTERFACE_PUBLIC
-  std::vector<CommandInterface> export_command_interfaces();
+  std::vector<std::shared_ptr<CommandInterface>> export_command_interfaces();
 
   HARDWARE_INTERFACE_PUBLIC
   return_type prepare_command_mode_switch(