boost::asio tcp异步\u读取永远不会返回
我试图将一些现有代码转换为使用boost的asio tcp套接字,而不是我们当前的实现。我可以从boost站点获得一个非常类似的示例(),但是当我尝试将代码放入自己的程序时,它就停止工作了 我在做什么:boost::asio tcp异步\u读取永远不会返回,boost,tcp,boost-asio,Boost,Tcp,Boost Asio,我试图将一些现有代码转换为使用boost的asio tcp套接字,而不是我们当前的实现。我可以从boost站点获得一个非常类似的示例(),但是当我尝试将代码放入自己的程序时,它就停止工作了 我在做什么: 启动服务器进程 服务器进程生成一个空套接字,并使用它(使用tcp::acceptor)侦听端口上的tcp连接(例如10010) 启动客户端进程 让客户端进程创建一个连接到服务器端口的套接字 当服务器看到客户端正在连接时,它开始侦听套接字上的数据(使用async_read),并创建另一个空套接字来
#ifndef CONNECTION_HPP
#define CONNECTION_HPP
#include
#include
#include
class ConnectionTransfer
{
public:
ConnectionTransfer(char* buffer, unsigned int size) :
buffer_(buffer), size_(size) {
}
virtual ~ConnectionTransfer(void){}
char* GetBuffer(){return buffer_;}
unsigned int GetSize(){return size_;}
virtual void CallbackForFinished() = 0;
protected:
char* buffer_;
unsigned int size_;
};
class ConnectionTransferInProgress
{
public:
ConnectionTransferInProgress(ConnectionTransfer* ct):
ct_(ct)
{}
~ConnectionTransferInProgress(void){}
void operator()(const boost::system::error_code& error){Other(error);}
void Other(const boost::system::error_code& error){
if(!error)
ct_->CallbackForFinished();
}
private:
ConnectionTransfer* ct_;
};
class Connection
{
public:
Connection(boost::asio::io_service& io_service):
sock_(io_service)
{}
~Connection(void){}
void AsyncSend(ConnectionTransfer* ct){
ConnectionTransferInProgress tip(ct);
//sock_->async_send(boost::asio::buffer(ct->GetBuffer(),
// static_cast(ct->GetSize())), tip);
boost::asio::async_write(sock_, boost::asio::buffer(ct->GetBuffer(),
static_cast(ct->GetSize())), boost::bind(
&ConnectionTransferInProgress::Other, tip, boost::asio::placeholders::error));
}
void AsyncReceive(ConnectionTransfer* ct){
ConnectionTransferInProgress tip(ct);
//sock_->async_receive(boost::asio::buffer(ct->GetBuffer(),
// static_cast(ct->GetSize())), tip);
boost::asio::async_read(sock_, boost::asio::buffer(ct->GetBuffer(),
static_cast(ct->GetSize())), boost::bind(
&ConnectionTransferInProgress::Other, tip, boost::asio::placeholders::error));
}
boost::asio::ip::tcp::socket& GetSocket(){return sock_;}
private:
boost::asio::ip::tcp::socket sock_;
};
#endif //CONNECTION_HPP
BoostConnectionClient.cpp:
#include "Connection.hpp"
#include
#include
#include
#include
using namespace boost::asio::ip;
bool connected;
bool gotTransfer;
class FakeTransfer : public ConnectionTransfer
{
public:
FakeTransfer(char* buffer, unsigned int size) : ConnectionTransfer(buffer, size)
{
}
void CallbackForFinished()
{
gotTransfer = true;
}
};
void ConnectHandler(const boost::system::error_code& error)
{
if(!error)
connected = true;
}
int main(int argc, char* argv[])
{
connected = false;
gotTransfer = false;
boost::asio::io_service io_service;
Connection* conn = new Connection(io_service);
tcp::endpoint ep(address::from_string("127.0.0.1"), 10011);
conn->GetSocket().async_connect(ep, ConnectHandler);
boost::thread t(boost::bind(&boost::asio::io_service::run, &io_service));
while(!connected)
{
boost::this_thread::sleep(boost::posix_time::millisec(1));
}
std::cout (angle brackets here) "Connected\n";
char data[100];
FakeTransfer* ft = new FakeTransfer(data, 100);
conn->AsyncReceive(ft);
while(!gotTransfer)
{
boost::this_thread::sleep(boost::posix_time::millisec(1));
}
std::cout (angle brackets here) "Done\n";
return 0;
}
BoostConnectionServer.cpp:
#include "Connection.hpp"
#include
#include
#include
#include
using namespace boost::asio::ip;
Connection* conn1;
bool conn1Done;
bool gotTransfer;
Connection* conn2;
class FakeAcceptor
{
public:
FakeAcceptor(boost::asio::io_service& io_service, const tcp::endpoint& endpoint)
:
io_service_(io_service),
acceptor_(io_service, endpoint)
{
conn1 = new Connection(io_service_);
acceptor_.async_accept(conn1->GetSocket(),
boost::bind(&FakeAcceptor::HandleAccept, this, conn1,
boost::asio::placeholders::error));
}
void HandleAccept(Connection* conn, const boost::system::error_code& error)
{
if(conn == conn1)
conn1Done = true;
conn2 = new Connection(io_service_);
acceptor_.async_accept(conn2->GetSocket(),
boost::bind(&FakeAcceptor::HandleAccept, this, conn2,
boost::asio::placeholders::error));
}
boost::asio::io_service& io_service_;
tcp::acceptor acceptor_;
};
class FakeTransfer : public ConnectionTransfer
{
public:
FakeTransfer(char* buffer, unsigned int size) : ConnectionTransfer(buffer, size)
{
}
void CallbackForFinished()
{
gotTransfer = true;
}
};
int main(int argc, char* argv[])
{
boost::asio::io_service io_service;
conn1Done = false;
gotTransfer = false;
tcp::endpoint endpoint(tcp::v4(), 10011);
FakeAcceptor fa(io_service, endpoint);
boost::thread t(boost::bind(&boost::asio::io_service::run, &io_service));
while(!conn1Done)
{
boost::this_thread::sleep(boost::posix_time::millisec(1));
}
std::cout (angle brackets here) "Accepted incoming connection\n";
char data[100];
FakeTransfer* ft = new FakeTransfer(data, 100);
conn1->AsyncReceive(ft);
while(!gotTransfer)
{
boost::this_thread::sleep(boost::posix_time::millisec(1));
}
std::cout (angle brackets here) "Success!\n";
return 0;
}
我四处找了一下,但运气不太好。据我所知,我几乎完全符合样本,所以我一定忽略了一些小东西
谢谢 在客户端代码中,您的
ConnectHandler()
回调函数只设置一个值,然后返回,而不向io_服务发布任何更多工作。此时,async\u connect()
操作是与io\u服务相关的唯一工作;因此,当ConnectHandler()
返回时,就不再有与io_服务相关的工作了。因此,后台线程对io\u service.run()
的调用返回,线程退出
一个可能的选项是从ConnectHandler()
中调用conn->AsyncReceive()
,这样在ConnectHandler()
返回之前调用async\u read()
,因此后台线程对io\u service.run()
的调用将不会返回
另一个更简单的选项是,在创建调用io_service::run的线程之前实例化io_service::work实例(从技术上讲,您可以在io_service.run()
调用返回之前的任何时候执行此操作):
这在io_服务文档中有记录:
正在停止io_服务以防止其工作耗尽
有些应用程序可能需要防止io_服务对象的run()调用在没有更多工作要做时返回。例如,io_服务可能在应用程序异步操作之前启动的后台线程中运行。可以通过创建io_service::work类型的对象来保持run()调用的运行:
异步读取在哪一侧永远不会返回?
...
// some point in the main() method, prior to creating the background thread
boost::asio::io_service::work work(io_service)
...