我正在制作一个客户端套接字。
为了让测试人员更轻松，我想指定套接字将使用的网卡和端口。
昨天，在谷歌搜索中，我发现：将 boost asio 绑定到本地 tcp 端点 https://stackoverflow.com/questions/8416917/binding-boost-asio-to-local-tcp-endpoint
通过执行 open、bind 和 async_connect，我能够绑定到特定的网卡，并且开始在 Wireshark 中看到流量。
然而，Wireshark 报告该套接字已被分配了一个随机端口，而不是我指定的端口。我认为如果端口正在使用中，它会填写传递给绑定方法的 error_code。
我究竟做错了什么？
这是我的最小示例，从我的真实解决方案中提取和编辑。
// Boost Includes
#include <boost/asio.hpp>
#include <boost/atomic.hpp>
#include <boost/bind.hpp>
#include <boost/thread.hpp>
#include <boost/thread/condition_variable.hpp>
// Standard Includes
#include <exception>
#include <memory>
#include <string>
#include <sstream>
boost::asio::io_service g_ioService; /** ASIO sockets require an io_service to run on*/
boost::thread g_thread; /** thread that will run the io_service and hence where callbacks are called*/
boost::asio::ip::tcp::socket g_socket(g_ioService); /** Aync socket*/
boost::asio::ip::tcp::resolver g_resolver(g_ioService); /** Resolves IP Addresses*/
//--------------------------------------------------------------------------------------------------
void OnConnect(const boost::system::error_code & errorCode, boost::asio::ip::tcp::resolver::iterator endpoint)
{
if (errorCode || endpoint == boost::asio::ip::tcp::resolver::iterator())
{
// Error - An error occured while attempting to connect
throw std::runtime_error("An error occured while attempting to connect");
}
// We connected to an endpoint
/*
// Start reading from the socket
auto callback = boost::bind(OnReceive, boost::asio::placeholders::error);
boost::asio::async_read_until(g_socket, m_receiveBuffer, '\n', callback);
*/
}
//--------------------------------------------------------------------------------------------------
void Connect()
{
const std::string hostName = "10.84.0.36";
const unsigned int port = 1007;
// Resolve to translate the server machine name into a list of endpoints
std::ostringstream converter;
converter << port;
const std::string portAsString = converter.str();
boost::asio::ip::tcp::resolver::query query(hostName, portAsString);
boost::system::error_code errorCode;
boost::asio::ip::tcp::resolver::iterator itEnd;
boost::asio::ip::tcp::resolver::iterator itEndpoint = g_resolver.resolve(query, errorCode);
if (errorCode || itEndpoint == itEnd)
{
// Error - Could not resolve either machine
throw std::runtime_error("Could not resolve either machine");
}
g_socket.open(boost::asio::ip::tcp::v4(), errorCode);
if (errorCode)
{
// Could open the g_socket
throw std::runtime_error("Could open the g_socket");
}
boost::asio::ip::tcp::endpoint localEndpoint(boost::asio::ip::address::from_string("10.86.0.18"), 6000);
g_socket.bind(localEndpoint, errorCode);
if (errorCode)
{
// Could bind the g_socket to local endpoint
throw std::runtime_error("Could bind the socket to local endpoint");
}
// Attempt to asynchronously connect using each possible end point until we find one that works
boost::asio::async_connect(g_socket, itEndpoint, boost::bind(OnConnect, boost::asio::placeholders::error, boost::asio::placeholders::iterator));
}
//--------------------------------------------------------------------------------------------------
void g_ioServiceg_threadProc()
{
try
{
// Connect to the server
Connect();
// Run the asynchronous callbacks from the g_socket on this thread
// Until the io_service is stopped from another thread
g_ioService.run();
}
catch (...)
{
throw std::runtime_error("unhandled exception caught from io_service g_thread");
}
}
//--------------------------------------------------------------------------------------------------
int main()
{
// Start up the IO service thread
g_thread.swap(boost::thread(g_ioServiceg_threadProc));
// Hang out awhile
boost::this_thread::sleep_for(boost::chrono::seconds(60));
// Stop the io service and allow the g_thread to exit
// This will cancel any outstanding work on the io_service
g_ioService.stop();
// Join our g_thread
if (g_thread.joinable())
{
g_thread.join();
}
return true;
}
正如您在下面的屏幕截图中看到的，选择了随机端口 32781，而不是我请求的端口 6000。
