UdpDestination.hpp

// SPDX-FileCopyrightText: 2026 Vincent Leroy
// SPDX-License-Identifier: MIT
//
// This file is part of dfx.
//
// Licensed under the MIT License. See the LICENSE file in the project root
// for full license information.
 
#pragma once
 
// Standard includes
#include <queue>
#include <random>
 
// Project includes
#include "DestinationTransport.hpp"
#include <dfx-fdwatch/PollerFd.hpp>
 
namespace dfx::Core
{
class UdpDestination : public DestinationTransport
{
    enum class WriteResult
    {
        Success,
        Partial,
        Queued,
        Error,
    };
 
public:
    static constexpr auto defaultMtuNetworkOverhead = 64;
 
public:
    UdpDestination(Endpoint endpoint, nlohmann::json config);
 
public:
    void start(FdWatch::Poller & poller) override;
    void stop() noexcept override;

    bool deliver(MessagePtr message) override;
 
private:
    WriteResult _writeData(std::vector<uint8_t> data);
    void _onSocketEvent(FdWatch::EventTriggers events);
 
private:
    FdWatch::PollerFd _socket;
    FdWatch::Poller * _poller;
    std::mt19937 _gen;
    std::uniform_int_distribution<uint32_t> _messageIdGen;
    uint32_t _mtu = 0;
    uint32_t _mtuNetworkOverhead = defaultMtuNetworkOverhead;
 
private:
    bool _canWrite = false;
    std::queue<std::vector<uint8_t>> _pendingData;
};
} // !namespace dfx::Core