C++ boost::asio::deadline#u计时器不';t调用处理程序
我有一个tcp客户端,它轮询服务器以获得一个有截止日期的答案,这样,如果无法到达服务器,客户端就不会被阻止。我遇到的问题是,C++ boost::asio::deadline#u计时器不';t调用处理程序,c++,boost,boost-asio,C++,Boost,Boost Asio,我有一个tcp客户端,它轮询服务器以获得一个有截止日期的答案,这样,如果无法到达服务器,客户端就不会被阻止。我遇到的问题是,async\u wait似乎从未调用其处理程序,在客户端连接失败时有效地阻止了客户端。对tcpPoll的每次调用都有自己的线程(这就是为什么我创建了一个新的io\u服务),但即使没有多线程,它似乎也无法工作。另外,NetworkEntity对象在其生命周期内可以多次调用tcpPoll 我的问题是:是什么阻止了截止时间\u计时器调用其处理程序?(以及如何修复) 以下是一些相关
async\u wait
似乎从未调用其处理程序,在客户端连接失败时有效地阻止了客户端。对tcpPoll
的每次调用都有自己的线程(这就是为什么我创建了一个新的io\u服务
),但即使没有多线程,它似乎也无法工作。另外,NetworkEntity
对象在其生命周期内可以多次调用tcpPoll
我的问题是:是什么阻止了截止时间\u计时器调用其处理程序?(以及如何修复)
以下是一些相关的代码,只要没有任何故障(连接、写入、读取),这些代码就可以正常工作(如果有点长,请原谅):
void NetworkEntity::stop()
{
停止=真;
//闭合插座
//取消超时
}
无效网络实体::检查超时(常量boost::系统::错误代码和错误)
{
如果(停止)
返回;
如果(timeout.expires_at(),我想您一定会被io_服务的多个实例弄糊涂了
我认为这是因为在您的代码中,您从未显示如何初始化timeout
。并且您用于连接的io\u服务
实例仅在tcpPoll
函数中实例化……这让我相信您是在一个单独的io上意外注册了截止时间计时器你连跑都不跑
下面是一个实际可行的版本,注意:
它已经消除了停止
布尔值,因为它是不必要的,并且必然会混淆
有关如何检测各种程序流,请参阅检查超时
和停止
的新实现
完整的代码是自包含的,只比您在问题中发布的代码多几行
#包括
#包括
#包括
使用tcp=boost::asio::ip::tcp;
结构网络实体{
boost::asio::io_服务io_服务;
boost::asio::deadline\u timer timeout{io\u service};
std::string address=“localhost”;
std::字符串端口=“6767”;
int超时=3;
boost::共享\u ptr套接字\uu;
boost::asio::streambuf请求,应答;
无效停止()
{
如果(插座)
{
套接字->取消();
套接字->关闭();
}
超时。取消();
io_服务。停止();
}
无效检查超时(const boost::system::error\u代码和错误)
{
if(error!=boost::asio::error::operation\u中止)
{
停止();
std::下一次是否可以让您的示例自包含?这样的错误可能很明显。这样,我们就花时间“制作”io服务、截止时间计时器、地址/端口值,“猜测”套接字将共享给一个(为什么?)而请求/应答(可能)而且,最糟糕的是,我们根据自己的经验来实现这些,而不一定是您实际如何实现的(这使得我们更难看出是什么让您绊倒了)注意!下次我同意sehe先生的观点,你离成为asio专家不远了亲爱的M先生。asio学习曲线有点难,那篇文章可能会对你有所帮助。我想你是对的,我在构造函数中初始化了timeout\uuu
(我没有显示)使用我的主io_服务
。当我从一个io_服务
更改为每个线程一个时,我没有想到这一点。谢谢!
void NetworkEntity::stop()
{
stopped_ = true;
//close socket
//cancel timeout
}
void NetworkEntity::check_timeout(const boost::system::error_code& error)
{
if (stopped_)
return;
if (timeout_.expires_at() <= boost::asio::deadline_timer::traits_type::now())
{
stop();
timeout_.expires_at(boost::posix_time::pos_infin);
std::cout << address_ << " timed out\n";
}
timeout_.async_wait(boost::bind(&NetworkEntity::check_timeout, this, boost::asio::placeholders::error));
}
std::vector<std::string> NetworkEntity::tcpPoll(const char* message, const char endOfMessage)
{
boost::asio::io_service io_service;
stopped_ = false;
timeout_.expires_from_now(boost::posix_time::seconds(TIMEOUT_));
timeout_.async_wait(boost::bind(&NetworkEntity::check_timeout, this, boost::asio::placeholders::error));
tcp::resolver resolver(io_service);
start_connect(&io_service, resolver.resolve(tcp::resolver::query(address_, port_)), message, endOfMessage);
io_service.run();
//retrieve answer from class
//return answer
}
void NetworkEntity::start_connect(boost::asio::io_service* io_service, tcp::resolver::iterator endpoint_iterator, const std::string message, const char endOfMessage)
{
socket_.reset(new tcp::socket(*io_service));
socket_->async_connect(endpoint_iterator->endpoint(),
boost::bind(&NetworkEntity::handle_connect, this, io_service, boost::asio::placeholders::error, endpoint_iterator, message, endOfMessage));
}
void NetworkEntity::handle_connect(boost::asio::io_service* io_service, const boost::system::error_code& err, tcp::resolver::iterator endpoint_iterator, const std::string message, const char endOfMessage)
{
if(stopped_)
return;
if (err)
{
std::cout << "Connect error: " << err.message() << "\n";
stop();
}
else
{
start_write(message, endOfMessage);
}
}
void NetworkEntity::start_write(const std::string message, const char endOfMessage)
{
std::ostream request_stream(&request_);
request_stream << message;
boost::asio::async_write(*socket_, request_,
boost::bind(&NetworkEntity::handle_write, this, boost::asio::placeholders::error, endOfMessage));
}
void NetworkEntity::handle_write(const boost::system::error_code& error, const char endOfMessage)
{
if (stopped_)
return;
if (!error)
{
//sleep for 500ms to let time for the reciever to process info (had a bug on this one)
start_read(endOfMessage);
}
else
{
std::cout << "write error : " << error.message() << "\n";
stop();
}
}
void NetworkEntity::start_read(const char endOfMessage)
{
boost::asio::async_read_until(*socket_, answer_, endOfMessage,
boost::bind(&NetworkEntity::handle_read, this, boost::asio::placeholders::error));
}
void NetworkEntity::handle_read(const boost::system::error_code& error)
{
if (stopped_)
return;
if (error)
{
std::cout << "read error : " << error.message() << "\n";
stop();
}
else
{
stop();
}
}
#include <iostream>
#include <boost/asio.hpp>
#include <boost/bind.hpp>
using tcp = boost::asio::ip::tcp;
struct NetworkEntity {
boost::asio::io_service io_service;
boost::asio::deadline_timer timeout_{io_service};
std::string address_ = "localhost";
std::string port_ = "6767";
int TIMEOUT_ = 3;
boost::shared_ptr<tcp::socket> socket_;
boost::asio::streambuf request_, answer_;
void stop()
{
if (socket_)
{
socket_->cancel();
socket_->close();
}
timeout_.cancel();
io_service.stop();
}
void check_timeout(const boost::system::error_code& error)
{
if (error != boost::asio::error::operation_aborted)
{
stop();
std::cout << address_ << " timed out\n";
}
timeout_.async_wait(boost::bind(&NetworkEntity::check_timeout, this, boost::asio::placeholders::error));
}
std::vector<std::string> tcpPoll(const char* message, const char endOfMessage)
{
timeout_.expires_from_now(boost::posix_time::seconds(TIMEOUT_));
timeout_.async_wait(boost::bind(&NetworkEntity::check_timeout, this, boost::asio::placeholders::error));
tcp::resolver resolver(io_service);
start_connect(&io_service, resolver.resolve(tcp::resolver::query(address_, port_)), message, endOfMessage);
io_service.run();
//retrieve answer from class
//return answer
std::ostringstream oss;
oss << &answer_;
return { oss.str() };
}
void start_connect(boost::asio::io_service* io_service, tcp::resolver::iterator endpoint_iterator, const std::string message, const char endOfMessage)
{
socket_.reset(new tcp::socket(*io_service));
socket_->async_connect(endpoint_iterator->endpoint(),
boost::bind(&NetworkEntity::handle_connect, this, io_service, boost::asio::placeholders::error, endpoint_iterator, message, endOfMessage));
}
void handle_connect(boost::asio::io_service* io_service,
const boost::system::error_code& err,
tcp::resolver::iterator endpoint_iterator,
const std::string message,
const char endOfMessage)
{
if (err)
{
std::cout << "Connect error: " << err.message() << "\n";
stop();
}
else
{
start_write(message, endOfMessage);
}
}
void start_write(const std::string message, const char endOfMessage)
{
std::ostream request_stream(&request_);
request_stream << message;
boost::asio::async_write(*socket_, request_,
boost::bind(&NetworkEntity::handle_write, this, boost::asio::placeholders::error, endOfMessage));
}
void handle_write(const boost::system::error_code& error, const char endOfMessage)
{
if (!error)
{
//sleep for 500ms to let time for the reciever to process info (had a bug on this one)
start_read(endOfMessage);
}
else
{
std::cout << "write error : " << error.message() << "\n";
stop();
}
}
void start_read(const char endOfMessage)
{
boost::asio::async_read_until(*socket_, answer_, endOfMessage,
boost::bind(&NetworkEntity::handle_read, this, boost::asio::placeholders::error));
}
void handle_read(const boost::system::error_code& error)
{
if (error)
{
std::cout << "read error : " << error.message() << "\n";
}
stop();
}
};
int main()
{
NetworkEntity ne;
for (auto& s : ne.tcpPoll("this is my request", '\n'))
{
std::cout << "Line: '" << s << "'\n";
}
}