cpp_callback_trampoline.hpp

// 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
{
 
 
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_