.. _program_listing_file_include_hardware_interface_system_interface.hpp:

Program Listing for File system_interface.hpp
=============================================

|exhale_lsh| :ref:`Return to documentation for file <file_include_hardware_interface_system_interface.hpp>` (``include/hardware_interface/system_interface.hpp``)

.. |exhale_lsh| unicode:: U+021B0 .. UPWARDS ARROW WITH TIP LEFTWARDS

.. code-block:: cpp

   // Copyright 2020 - 2021 ros2_control Development Team
   //
   // 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 HARDWARE_INTERFACE__SYSTEM_INTERFACE_HPP_
   #define HARDWARE_INTERFACE__SYSTEM_INTERFACE_HPP_
   
   #include <memory>
   #include <string>
   #include <vector>
   
   #include "hardware_interface/handle.hpp"
   #include "hardware_interface/hardware_info.hpp"
   #include "hardware_interface/types/hardware_interface_return_values.hpp"
   #include "hardware_interface/types/lifecycle_state_names.hpp"
   #include "lifecycle_msgs/msg/state.hpp"
   #include "rclcpp/duration.hpp"
   #include "rclcpp/time.hpp"
   #include "rclcpp_lifecycle/node_interfaces/lifecycle_node_interface.hpp"
   #include "rclcpp_lifecycle/state.hpp"
   
   namespace hardware_interface
   {
   
   using CallbackReturn = rclcpp_lifecycle::node_interfaces::LifecycleNodeInterface::CallbackReturn;
   
   class SystemInterface : public rclcpp_lifecycle::node_interfaces::LifecycleNodeInterface
   {
   public:
     SystemInterface()
     : lifecycle_state_(rclcpp_lifecycle::State(
         lifecycle_msgs::msg::State::PRIMARY_STATE_UNKNOWN, lifecycle_state_names::UNKNOWN))
     {
     }
   
   
     SystemInterface(const SystemInterface & other) = delete;
   
     SystemInterface(SystemInterface && other) = default;
   
     virtual ~SystemInterface() = default;
   
   
     virtual CallbackReturn on_init(const HardwareInfo & hardware_info)
     {
       info_ = hardware_info;
       return CallbackReturn::SUCCESS;
     };
   
   
     virtual std::vector<StateInterface> export_state_interfaces() = 0;
   
   
     virtual std::vector<CommandInterface> export_command_interfaces() = 0;
   
   
     virtual return_type prepare_command_mode_switch(
       const std::vector<std::string> & /*start_interfaces*/,
       const std::vector<std::string> & /*stop_interfaces*/)
     {
       return return_type::OK;
     }
   
     // Perform switching to the new command interface.
     virtual return_type perform_command_mode_switch(
       const std::vector<std::string> & /*start_interfaces*/,
       const std::vector<std::string> & /*stop_interfaces*/)
     {
       return return_type::OK;
     }
   
   
     virtual return_type read(const rclcpp::Time & time, const rclcpp::Duration & period) = 0;
   
   
     virtual return_type write(const rclcpp::Time & time, const rclcpp::Duration & period) = 0;
   
   
     virtual std::string get_name() const { return info_.name; }
   
   
     virtual std::string get_group_name() const { return info_.group; }
   
   
     const rclcpp_lifecycle::State & get_state() const { return lifecycle_state_; }
   
   
     void set_state(const rclcpp_lifecycle::State & new_state) { lifecycle_state_ = new_state; }
   
   protected:
     HardwareInfo info_;
     rclcpp_lifecycle::State lifecycle_state_;
   };
   
   }  // namespace hardware_interface
   #endif  // HARDWARE_INTERFACE__SYSTEM_INTERFACE_HPP_