Question

我正在尝试编写一个允许多个客户端连接的简单服务器。当我运行我的程序时，我得到以下错误作为输出：

[3730] Press [return] to exit.
Listening on: 127.0.0.1:7777
[5d0] Thread Start
Error: system:995 The I/O operation has been aborted because of either a 
thread exit or an application request

我认为这是因为我的客户端对象超出了范围，但我不完全确定这是否真的是问题，或者我的代码是否存在其他问题。

ClientNetwork::ClientNetwork(asio::io_service& ios, const asio::ip::tcp::endpoint& edp) : mIOService(ios), mAcceptor(ios, edp)
{
    /*mAcceptor.open(edp.protocol());
    mAcceptor.set_option(boost::asio::ip::tcp::acceptor::reuse_address(false));*/
    listen();
}
ClientNetwork::~ClientNetwork()
{
    boost::system::error_code ec;
    mAcceptor.close(ec);

    mConnectionThreads.join_all();
    mClients.clear();
    std::cout << "KILLING NETWORK" << std::endl;
}
void ClientNetwork::listen()
{
    mConnectionThreads.create_thread(boost::bind(&ClientNetwork::connectionThread, this));
    Client* c = new Client(mIOService);
    mAcceptor.listen(boost::asio::socket_base::max_connections);
    mAcceptor.async_accept(*c->getSocket(), boost::bind(&ClientNetwork::handleAccept, this, _1, c));

}

void ClientNetwork::handleAccept(const boost::system::error_code& error, Client* client)
{

    if (!error)
    {
        mClients.push_back(client);
        mConnectionThreads.create_thread(boost::bind(&ClientNetwork::connectionThread, this));
        std::cout << mConnectionThreads.size() << std::endl;
    }
    else
    {
        std::cout << "Error: " << error << " " << error.message() << std::endl;
    }
}

这是我的主要内容（不确定它是否完全有用，但觉得包含它会很好：

int main(int argc, char * argv[])
{
    boost::shared_ptr< boost::asio::io_service > io_service(
        new boost::asio::io_service
    );
    boost::shared_ptr< boost::asio::io_service::work > work(
        new boost::asio::io_service::work(*io_service)
    );
    boost::shared_ptr< boost::asio::io_service::strand > strand(
        new boost::asio::io_service::strand(*io_service)
    );
    global_stream_lock.lock();
    std::cout << "[" << boost::this_thread::get_id()
        << "] Press [return] to exit." << std::endl;
    global_stream_lock.unlock();

    /*boost::thread_group worker_threads;
    for (int x = 0; x < 2; ++x)
    {
        worker_threads.create_thread(boost::bind(&WorkerThread, io_service));
    }*/

    /*boost::shared_ptr< boost::asio::ip::tcp::acceptor > acceptor(
        new boost::asio::ip::tcp::acceptor(*io_service)
    );
    boost::shared_ptr< boost::asio::ip::tcp::socket > sock(
        new boost::asio::ip::tcp::socket(*io_service)
    );*/

    try
    {
        boost::asio::ip::tcp::resolver resolver(*io_service);
        boost::asio::ip::tcp::resolver::query query(
            "127.0.0.1",
            boost::lexical_cast< std::string >(7777)
        );
        boost::asio::ip::tcp::endpoint endpoint = *resolver.resolve(query);



        ClientNetwork clientNet(*io_service, endpoint);

        global_stream_lock.lock();
        std::cout << "Listening on: " << endpoint << std::endl;
        global_stream_lock.unlock();
    }
    catch (std::exception & ex)
    {
        global_stream_lock.lock();
        std::cout << "[" << boost::this_thread::get_id()
            << "] Exception: " << ex.what() << std::endl;
        global_stream_lock.unlock();
    }

    std::cin.get();

    //worker_threads.join_all();

    return 0;
}

Answer 1

创建ClientNetwork对象后，首先启动异步操作时，应运行io_service::run方法处理事件循环中的处理程序，然后程序运行，直到至少有一个异步操作要执行。

在try范围结束时io_service->run()：

    ClientNetwork clientNet(*io_service, endpoint);

    global_stream_lock.lock();
    std::cout << "Listening on: " << endpoint << std::endl;
    global_stream_lock.unlock();
    io_service->run();

如果没有这个，ClientNetwork类的析构函数被调用，mAcceptor关闭并打印此错误消息

void ClientNetwork::handleAccept (...) {
  ...
  std::cout << "Error: " << error << " " << error.message() << std::endl;
}

Boost ASIO系统错误995：I / O操作已中止

1 个答案: