scope_exit.hpp

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// Copyright 2015-2020 Open Source Robotics Foundation, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
 
#ifndef RCPPUTILS__SCOPE_EXIT_HPP_
#define RCPPUTILS__SCOPE_EXIT_HPP_
 
#include <utility>
 
#include "rcutils/macros.h"
 
namespace rcpputils
{
 
template<typename CallableT>
struct scope_exit final
{
  explicit scope_exit(CallableT && callable)
  : callable_(std::forward<CallableT>(callable))
  {
  }
 
  scope_exit(const scope_exit &) = delete;
  scope_exit(scope_exit &&) = default;
 
  scope_exit & operator=(const scope_exit &) = delete;
  scope_exit & operator=(scope_exit &&) = default;
 
  ~scope_exit()
  {
    if (!cancelled_) {
      callable_();
    }
  }
 
  void cancel()
  {
    cancelled_ = true;
  }
 
private:
  CallableT callable_;
  bool cancelled_{false};
};
 
template<typename CallableT>
scope_exit<CallableT>
make_scope_exit(CallableT && callable)
{
  return scope_exit<CallableT>(std::forward<CallableT>(callable));
}
 
}  // namespace rcpputils
 
#define RCPPUTILS_SCOPE_EXIT(code) \
  auto RCUTILS_JOIN(scope_exit_, __LINE__) = rcpputils::make_scope_exit([&]() {code;})
 
#endif  // RCPPUTILS__SCOPE_EXIT_HPP_