ConfigSubscriptionHandle.h

#pragma once

#include <functional>
#include <list>
#include <memory>
#include <mutex>
#include <utility>

namespace facebook { namespace logdevice {

namespace configuration {
class UpdateableConfigBase;
enum class SubscriptionStatus;
using subscription_id_t = uint64_t;
} // namespace configuration

class ConfigSubscriptionHandle final {
 public:
  ConfigSubscriptionHandle() noexcept = default;

  ConfigSubscriptionHandle(configuration::UpdateableConfigBase* owner,
                           configuration::subscription_id_t sub_id) noexcept;

  ~ConfigSubscriptionHandle() noexcept;

  ConfigSubscriptionHandle(ConfigSubscriptionHandle&& other) noexcept;

  ConfigSubscriptionHandle&
  operator=(ConfigSubscriptionHandle&& other) noexcept;

  void unsubscribe() noexcept;

  void swap(ConfigSubscriptionHandle& other) noexcept {
    using std::swap;
    swap(owner_, other.owner_);
    swap(sub_id_, other.sub_id_);
  }

 private:
  std::weak_ptr<configuration::UpdateableConfigBase> owner_;
  configuration::subscription_id_t sub_id_;
};

}} // namespace facebook::logdevice

namespace std {
inline void
swap(facebook::logdevice::ConfigSubscriptionHandle& left,
     facebook::logdevice::ConfigSubscriptionHandle& right) noexcept {
  left.swap(right);
}
} // namespace std