Question

我试图用c ++语言创建一个TCP服务器 - 客户端聊天程序，但是在客户端连接中，connect函数无效，我的连接终止。我尝试过setsockopt方法以及更改端口号但是什么都没有用。请帮帮我!! 这是客户方：

#include <iostream>
#include <bits/stdc++.h>
#include <stdio.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <stdlib.h>
#include <unistd.h>
#include <netdb.h>
#include <netinet/in.h>
#include <arpa/inet.h>
using namespace std;

#define IP "10.31.10.157"
int main()
{
    int port=80;
    int buffersize= 1024;
    char buffer[buffersize];
    int client,server;

    sockaddr_in server_addr;
    client=socket(AF_INET,SOCK_STREAM,0);
    if(client<0)
    {
        cout<<"Error creating socket "<<endl;
        exit(1);
    }


    cout<<"Client Socket Created ";
    server_addr.sin_family=AF_INET;
    server_addr.sin_addr.s_addr= inet_addr(IP);
    //server_addr.sin_addr.s_addr= inet_addr(INADDR_ANY);
    server_addr.sin_port=htons(port);
    if(connect(client,(struct sockaddr *) &server_addr, sizeof(server_addr))>0)
    {
        cout<<"\nWrite Bye to end connection\n";

        while(1)
        {
            cout<<"Server: ";
            recv(client,buffer,buffersize,0);
            printf("%s\n",buffer);

            cout<<"Client: ";
            gets(buffer);
            send(client,buffer,buffersize,0);
            if(strcmp(buffer,"Bye")==0)
                break;
        }


    }
    else
        cout<<"Connection Failed";
    cout<<"Connection terminated \n";
    //close(client);
}

服务器端：

#include <iostream>
#include <bits/stdc++.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <stdio.h>
#include <netinet/in.h>
#include <arpa/inet.h>
using namespace std;

int main()
{
    int server,client;
    int buffersize=1024;
    char buffer[buffersize];
    int portNum=80;

    struct sockaddr_in server_addr;
    socklen_t size;
    client=socket(AF_INET,SOCK_STREAM,0);
    if(client<0)
    {
        cout<<"Error establishing connection "<<endl;
        return 0;
    }
    cout<<"Socket connection established \n";
    server_addr.sin_family= AF_INET;
    server_addr.sin_addr.s_addr= htons(INADDR_ANY);
    server_addr.sin_port= htons(portNum);
    if(bind(client, (struct sockaddr *) &server_addr, sizeof(server_addr))<0)
    {
        cout<<"Error binding socket "<<endl;
        return 0;
    }
    size= sizeof(server_addr);
    cout<<"Looking for clients";
    listen(client,1);
    server= accept(client, (struct sockaddr *)&server_addr, &size);
    if(server<0)
    {
        cout<<"Error on accepting"<<endl;
        return 0;
    }

    if(server>0)
    {
        cout<<"\nType Bye to end connection\n";
        while(1)
        {
            cout<<"Server: ";
            gets(buffer);
            send(server,buffer,buffersize,0);
            recv(server,buffer,buffersize,0);
            cout<<"Client: ";
            printf("%s",buffer);
            cout<<"\n";
            if(strcmp(buffer,"Bye")==0)
                break;

        }
    }
    cout<<"Connection terminated ";
    //close(client);
}

服务器程序运行正常，但客户端没有连接到服务器!!

Answer 1

我将分享我正在使用的TCPClient代码。看看你是否可以使用它（直接或修改你的代码）;

TCPClient.h

#pragma once
#define WIN32_LEAN_AND_MEAN
#include <windows.h>
#include <winsock2.h>
#include <ws2tcpip.h>
#include <stdlib.h>
#include <stdio.h>
#include <string>
#include <iostream>


// Need to link with Ws2_32.lib, Mswsock.lib, and Advapi32.lib
#pragma comment (lib, "Ws2_32.lib")
#pragma comment (lib, "Mswsock.lib")
#pragma comment (lib, "AdvApi32.lib")

class TCPClient
{
private:
    static const int DEFAULT_BUFLEN = 512;
    static const std::string DEFAULT_PORT;
    static const int DEFAULT_TIMEOUT = 2000;
    struct addrinfo *result = NULL;
    struct addrinfo *ptr = NULL;
    struct addrinfo hints;
    SOCKET m_connect_socket = INVALID_SOCKET;

public:
    TCPClient();
    ~TCPClient();
    bool Connect(const std::string& address, const std::string& port = DEFAULT_PORT);
    bool Send(const std::string& data);
    bool SetTimeout(int timeout);
    std::string Receive();
};

TCPClient.cpp

#include "stdafx.h"
#include "TCPClient.h"


const std::string TCPClient::DEFAULT_PORT = "50015";

TCPClient::TCPClient()
{   
}

TCPClient::~TCPClient()
{
    closesocket(m_connect_socket);
    WSACleanup();
}



bool TCPClient::Connect(const std::string& address, const std::string& port )
{
    WSADATA wsaData;
    if (WSAStartup(MAKEWORD(2, 2), &wsaData) != 0)
    {
        return false;
    }
    ZeroMemory(&hints, sizeof(hints));
    hints.ai_family = AF_UNSPEC;
    hints.ai_socktype = SOCK_STREAM;
    hints.ai_protocol = IPPROTO_TCP;

    if (getaddrinfo(address.c_str(), port.c_str(), &hints, &result) != 0)
    {
        WSACleanup();
        return false;
    }

    for (ptr = result; ptr != NULL; ptr = ptr->ai_next) 
    {
        m_connect_socket = socket(ptr->ai_family, ptr->ai_socktype,
            ptr->ai_protocol);
        if (m_connect_socket == INVALID_SOCKET) 
        {
            WSACleanup();
            return false;
        }

        if (connect(m_connect_socket, ptr->ai_addr, (int)ptr->ai_addrlen) == SOCKET_ERROR) {
            closesocket(m_connect_socket);
            m_connect_socket = INVALID_SOCKET;
            continue;
        }
        if (!SetTimeout(DEFAULT_TIMEOUT))
        {
            return false;
        }
        break;
    }
    freeaddrinfo(result);

    if (m_connect_socket == INVALID_SOCKET) 
    {
        WSACleanup();
        return false;
    }
    return true;
}


bool TCPClient::Send(const std::string& data)
{
    return send(m_connect_socket, data.c_str(), data.length(), 0) != SOCKET_ERROR;
}

bool TCPClient::SetTimeout(int timeout)
{
    return setsockopt(m_connect_socket, SOL_SOCKET, SO_RCVTIMEO, (const char *)&timeout,
        sizeof(timeout)) == 0;
}

std::string TCPClient::Receive()
{
    char recvbuf[DEFAULT_BUFLEN]="\0";
    recv(m_connect_socket, recvbuf, DEFAULT_BUFLEN, 0);
    return recvbuf;
}

用法

std::string reply;
std::string message = "message";
TCPClient client;

if (client.Connect("127.0.0.1", "50015"))  //check if connection is successful
{
      client.SetTimeout(1000);  // set the timeout to 1 sec, default timeout=2sec. This line is not necessary
      client.Send(message);      //send message
      reply = client.Receive();   //receive reply
      std::cout << "Reply: " << reply << std::endl;
}
else
{
      std::cout << "Connection to socket un-successful\n";
}

return 0;

或使用提升http://www.boost.org/doc/libs/1_42_0/doc/html/boost_asio/tutorial/tutdaytime1.html。

TCP聊天 - 客户端中的连接功能不起作用

1 个答案: