srsRAN_4G/lib/include/srsran/adt/scope_exit.h

/**
 * Copyright 2013-2021 Software Radio Systems Limited
 *
 * This file is part of srsRAN.
 *
 * srsRAN is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as
 * published by the Free Software Foundation, either version 3 of
 * the License, or (at your option) any later version.
 *
 * srsRAN is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Affero General Public License for more details.
 *
 * A copy of the GNU Affero General Public License can be found in
 * the LICENSE file in the top-level directory of this distribution
 * and at http://www.gnu.org/licenses/.
 *
 */

#ifndef SRSRAN_SCOPE_EXIT_H
#define SRSRAN_SCOPE_EXIT_H

#include <type_traits>
#include <utility>

namespace srsran {

namespace detail {

template <typename Callable>
struct scope_exit {
  template <typename C>
  explicit scope_exit(C&& f_) : exit_function(std::forward<C>(f_))
  {}
  scope_exit(scope_exit&& rhs) noexcept : exit_function(std::move(rhs.exit_function)), active(rhs.active)
  {
    rhs.release();
  }
  scope_exit(const scope_exit&) = delete;
  scope_exit& operator=(const scope_exit&) = delete;
  scope_exit& operator=(scope_exit&&) noexcept = delete;
  ~scope_exit()
  {
    if (active) {
      exit_function();
    }
  }

  void release() { active = false; }

private:
  Callable exit_function;
  bool     active = true;
};

} // namespace detail

/**
 * @brief Defers callable call to scope exit
 * @tparam Callable Any type with a call operator
 * @param callable function that is called at scope exit
 * @return object that has to be stored in a local variable
 */
template <typename Callable>
detail::scope_exit<typename std::decay<Callable>::type> make_scope_exit(Callable&& callable)
{
  return detail::scope_exit<typename std::decay<Callable>::type>{std::forward<Callable>(callable)};
}

#define DEFER(FUNC) auto on_exit_call = make_scope_exit([&]() { FUNC })

} // namespace srsran

#endif // SRSRAN_SCOPE_EXIT_H