packet_id_manager.hpp

// Copyright Takatoshi Kondo 2020
//
// Distributed under the Boost Software License, Version 1.0.
// (See accompanying file LICENSE_1_0.txt or copy at
// http://www.boost.org/LICENSE_1_0.txt)
 
#if !defined(ASYNC_MQTT_UTIL_PACKET_ID_MANAGER_HPP)
#define ASYNC_MQTT_UTIL_PACKET_ID_MANAGER_HPP
 
#include <optional>
 
#include <async_mqtt/util/value_allocator.hpp>
 
namespace async_mqtt {
 
template <typename PacketId>
class packet_id_manager {
    using packet_id_type = PacketId;
 
public:
 
    std::optional<packet_id_type> acquire_unique_id() {
        return va_.allocate();
    }
 
    bool register_id(packet_id_type packet_id) {
        return va_.use(packet_id);
    }
 
    bool is_used_id(packet_id_type packet_id) const {
        return va_.is_used(packet_id);
    }
 
    void release_id(packet_id_type packet_id) {
        va_.deallocate(packet_id);
    }
 
    void clear() {
        va_.clear();
    }
 
private:
    value_allocator<packet_id_type> va_ {1, std::numeric_limits<packet_id_type>::max()};
};
 
} // namespace async_mqtt
 
#endif // ASYNC_MQTT_UTIL_PACKET_ID_MANAGER_HPP