使用boost.asio的免费async_*函数时出现奇怪的错误

Getting weird error while using boost.asio's free async_* functions

本文关键字:函数 错误 asio boost 免费 async 使用      更新时间:2023-10-16

我在当前正在编写的应用程序中得到了以下代码片段:

#include "ClientSession.hpp"
void ClientSession::start(void)
{
    auto Self(shared_from_this());
    //boost::asio::read(this->_Socket, boost::asio::buffer(this->_ReadBuffer));
    //this->_Socket.get_io_service().post(boost::bind(&ClientSession::on_read, shared_from_this(), boost::system::error_code::error_code(), 0));
    boost::asio::async_read(this->_Socket, boost::asio::buffer(this->_ReadBuffer), boost::bind(&ClientSession::on_read, Self, _1, _2));
}
void ClientSession::on_read(const boost::system::error_code& Err_, size_t Bytes_)
{
    try 
    {
        if(Err_)
        {
            if(!(Err_ == boost::asio::error::eof || Err_ == boost::asio::error::connection_aborted))
            {
                throw std::runtime_error(Err_.message());
            }
            return;
        }
    }
    catch(std::exception& Ex_)
    {
        this->_OutputHandler.write_error(Ex_.what());
    }
}

调用ClientSession::start的代码是:

void Application::start_accept()
{
    using namespace boost::asio;
    ip::tcp::endpoint Endpoint( ip::address::from_string(this->_Config.get_client_login_server().first), this->_Config.get_client_login_server().second );
    this->_ClientAcceptor.open(Endpoint.protocol());
    this->_ClientAcceptor.bind(Endpoint);
    this->_ClientAcceptor.listen();
    std::shared_ptr<ClientSession> Session = ClientSession::create_new(this->_AsioService, this->_OutputHandler);
    this->_ClientAcceptor.async_accept(Session->get_socket(), boost::bind(&Application::handle_accept, shared_from_this(), Session, _1));
}

如果我用注释掉的一行运行应用程序,它运行得很好(在boost::asio::read版本中,从客户端传输的消息被写入读取缓冲区,在后版本中,处理程序函数被调用,没有任何问题),但如果尝试将我的应用程序与async_read部分一起使用,我的整个应用程序总是崩溃,而不调用完整句柄或!甚至读取一个字节!,至少从asio给我的输出来看是这样的:

@asio|1373633560.834957|0*1|socket@000000BD603D46C0.async_accept@asio|1373633573.324144|>1|ex=系统:0@asio|1373633573.324144|1*2|socket@000000BD603DBAB8.async_receive

我将它解压到一个名为"select_reactor.ipp"的文件中,在该文件中,应用程序试图获取一个boost::asio::detail::mutex::scoped_lock,但它看起来正在失败,该方法的完整代码是:

void select_reactor::start_op(int op_type, socket_type descriptor,
select_reactor::per_descriptor_data&, reactor_op* op,
bool is_continuation, bool)
{
  boost::asio::detail::mutex::scoped_lock lock(mutex_);
  if (shutdown_)
  {
    post_immediate_completion(op, is_continuation);
    return;
  }
  bool first = op_queue_[op_type].enqueue_operation(descriptor, op);
  io_service_.work_started();
  if (first)
    interrupter_.interrupt();
}

我不知道我可能做错了什么,但我不知道是什么,我希望有人能给我一个提示,我能做些什么来解决这个错误。

根据我到目前为止得到的评论,我将添加更完整的代码片段:我的io_service在我的应用程序类中:

class Application
    : public std::enable_shared_from_this<Application>
{
typedef boost::asio::io_service Service;
typedef boost::asio::ip::tcp::acceptor Acceptor;
public:
    Application(void) 
        : _ClientAcceptor(_AsioService), _ApplicationRunning(true)
    {
    }
    ~Application(void);
    /*
     * This is the main method which starts the actual program routine
     * called in main()
     */
    int run(void);
private:
    /*
     * Invokes the first accept and then invokes via async. handle_accept, which invokes itself repeatedly
     */
    void start_accept(void);
    /*
     * handle_accept calls NewClient_->start to invoke the communication with this client 
     */
    void handle_accept(std::shared_ptr<ClientSession> NewClient_, const boost::system::error_code& Err_);
    void loop_for_user_input(void);
    bool handle_user_input(const std::string& Msg_);
    /*
     * This method invokes the threads that call io_service::run()
     */
    static void start_service(Service& AsioService_) { try { AsioService_.run(); } catch(const std::exception& Ex_) { std::cout << Ex_.what() << std::endl; } }
private:
    Configuration _Config;
    Service _AsioService;
    Acceptor _ClientAcceptor;
    OutputHandler _OutputHandler;
    bool _ApplicationRunning;
};

运行方法:

int Application::run(void)
{
    try 
    {
        this->_Config.load();
        this->_OutputHandler.open(this->_Config.get_logs());
        this->start_accept();
        for(int i = 0; i < 4; i++)
        {
            std::thread t(start_service, std::ref(this->_AsioService));
            t.detach();
        }
        this->loop_for_user_input();
    }
    catch(const std::runtime_error& Ex_)
    {
        this->_OutputHandler.write_error(Ex_.what());
    }
    return 0;
}

我发现了错误,这只是我的_WIN32_WINNT预处理器指令中的一个拼写错误,将其设置为_WIN32_ WINNT 0x0601(适用于Windows 7)解决了问题。