提升::接受者::取消未按预期工作

boost::acceptor::cancel doesn't work as expected

本文关键字:工作 接受者 取消 提升      更新时间:2023-10-16

我已经使用boost实现了SocketServer。此套接字服务器旨在按如下方式工作:

  • 接受一定时间的连接
  • 达到超时后停止处理套接字

这是我的代码:

ServerSocket::ServerSocket(unsigned int port)
{
    _io_service.reset(new boost::asio::io_service()) ;
    _endpoint.reset(new boost::asio::ip::tcp::endpoint(boost::asio::ip::tcp::v4(), port));
    _acceptor.reset(new boost::asio::ip::tcp::acceptor(*_io_service, *_endpoint)) ;
    _newConnection = false; 
}
bool ServerSocket::accept(boost::asio::ip::tcp::socket& socket, int timeout)
{
    _newConnection = false;
    _acceptor->async_accept(socket, boost::bind(&ServerSocket::handleAccept, this, &socket));
    _io_service->reset();
    if (timeout > 0)
    {
        int incrementation = 1;
        int time_spent = 0;
        while (time_spent < timeout && !_io_service->poll_one())
        {
            time_spent += incrementation;
            sleep(incrementation);
        }
    }
    else
    {
        _io_service->run_one();
    }
    if (!_newConnection)
    {
        _acceptor->cancel();
    }
    return _newConnection;
}
void ServerSocket::handleAccept(boost::asio::ip::tcp::socket* pSocket)
{
    _newConnection = true;
};

我的问题是:当我调用带有超时和套接字 A 的 accept() 时。如果达到超时并且我使用新的套接字 B 再次调用它,如果 accept() 有效,我会处理 A 而不是 B。

告诉我是否缺少信息。

您可以简单地使用io_service的任务循环,并使用截止时间计时器来取消对接受器的操作。

住在科里鲁

#include <boost/asio.hpp>
#include <boost/bind.hpp>
using namespace boost;
using asio::ip::tcp;
struct ServerSocket
{
    asio::io_service _io_service;
    tcp::endpoint _endpoint;
    tcp::acceptor _acceptor;
    asio::deadline_timer _timer;
    bool _newConnection;
    ServerSocket(unsigned int port)
        : _io_service(),
          _endpoint(tcp::v4(), port),
          _acceptor(_io_service, _endpoint),
          _timer(_io_service),
          _newConnection(false)
    {
    }
    void timer_expired(boost::system::error_code ec)
    {
        if (!ec)
        {
            _acceptor.cancel();
        }
    }
    bool accept(boost::asio::ip::tcp::socket& socket, int timeout)
    {
        _newConnection = false;
        _io_service.reset();
        _timer.expires_from_now(boost::posix_time::seconds(timeout));
        _timer.async_wait(boost::bind(&ServerSocket::timer_expired, this, asio::placeholders::error));
        _acceptor.async_accept(socket, boost::bind(&ServerSocket::handleAccept, this, &socket, asio::placeholders::error));
        _io_service.run();
        return _newConnection;
    }
    void handleAccept(boost::asio::ip::tcp::socket* pSocket, boost::system::error_code ec)
    {
        if (!ec)
        {
            _timer.cancel();
            _newConnection = true;
        }
    };
};
int main()
{
    ServerSocket s(6767);
    tcp::socket socket(s._io_service);
    if (s.accept(socket, 3))
        std::cout << "Accepted connection from " << socket.remote_endpoint() << "n";
    else
        std::cout << "Timeout expiredn";
}

如果只是做!ec,您可能应该明确检查operation_canceled错误代码,但我会将其留给读者作为练习。