send_to_lobby.cpp

void ServerNetworker::registerlobby(Gamestate &state)
{
    xg::Guid message_type(LOBBY_MESSAGE_TYPE_REGISTER);
    xg::Guid lobbyid(GG2_IDENTIFIER);
    xg::Guid compatibility(COMPATIBILITY_IDENTIFIER);

    WriteBuffer buffer;

    // See https://github.com/Medo42/Faucet-Lobby/blob/master/Protocol%20Spec.txt for reference
    // https://github.com/PyGG2/PyGG2/blob/master/server/lobby.py is also helpful

    // Message type for lobby
    for (auto& byte : message_type._bytes)
    {
        buffer.write<uint8_t>(byte);
    }
    // Server id
    for (auto& byte : serverid._bytes)
    {
        buffer.write<uint8_t>(byte);
    }
    // Lobby id
    for (auto& byte : lobbyid._bytes)
    {
        buffer.write<uint8_t>(byte);
    }
    // Transport protocol (0=TCP, 1=UDP)
    buffer.write<uint8_t>(1);
    // Port number
    buffer.write<uint16_t>(host->address.port);
    // Number of total player slots
    buffer.write<uint16_t>(PLAYER_LIMIT);
    // Number of players ingame
    buffer.write<uint16_t>(static_cast<uint16_t>(state.playerlist.size()));
    // Number of AI bots
    buffer.write<uint16_t>(0);
    // Flags
    buffer.write<uint16_t>(0);

    std::map<std::string, std::string> data = {
        {"name", "Vanguard test server"},
        {"game", GAME_NAME},
        {"game_short", GAME_NAME_SHORT},
        {"game_ver", GAME_VERSION},
        {"game_url", GAME_URL},
        {"map", state.currentmap->name}
    };

    // Extra data

    // Write number of key/value pairs
    // Protocol_id isn't a string but fixed so doing it separately
    buffer.write<uint16_t>(data.size() + 1);

    // Compatibility flag
    buffer.write<uint8_t>(std::string("protocol_id").size());
    buffer.writestring("protocol_id");
    buffer.write<uint16_t>(16);
    for (auto& byte : compatibility._bytes)
    {
        buffer.write<uint8_t>(byte);
    }

    // Everything else
    for (auto& entry : data)
    {
        buffer.write<uint8_t>(entry.first.size());
        buffer.writestring(entry.first);
        buffer.write<uint16_t>(entry.second.size());
        buffer.writestring(entry.second);
    }

    std::ofstream file("lobby_registration.bin", std::ios_base::binary);
    file.write(static_cast<char*>(buffer.getdata()), buffer.length());
    file.close();

    Global::logging().print(__FILE__, __LINE__, "Sent packet to lobby");

    ENetPacket *lobbypacket = enet_packet_create(buffer.getdata(), buffer.length(), ENET_PACKET_FLAG_RELIABLE);
    enet_peer_send(lobby, 0, lobbypacket);
}