在引入#include <WinSock2.h>之前，定义：

#define FD_SETSIZE      1024

就能实现突破64个socket

客户端---------------：100个tcp的client去连接服务端

DataHeader.hpp

#ifndef _MessageHeader_hpp_
#define _MessageHeader_hpp_


enum CMD
{
    CMD_LOGIN,
    CMD_LOGIN_RET,
    CMD_LOGOUT,
    CMD_LOGOUT_RET,
    CMD_NEW_USER_JOIN,
    CMD_ERROR
};

struct DataHeader
{
    DataHeader()
    {
        dataLength = sizeof(DataHeader);
        cmd = CMD_ERROR;
    }
    short dataLength;
    short cmd;
};

struct Login :public DataHeader
{
    Login()
    {
        dataLength = sizeof(Login);
        cmd = CMD_LOGIN;
    }
    char userName[32];
    char passWord[32];
    char data[932];
};

struct LoginResult :public DataHeader
{
    LoginResult()
    {
        dataLength = sizeof(LoginResult);
        cmd = CMD_LOGIN_RET;
        ret = 1;
    }
    int ret;
    char data[992];
};

struct LogOut :public DataHeader
{
    LogOut()
    {
        dataLength = sizeof(LogOut);
        cmd = CMD_LOGOUT;
    }
    char userName[32];
};

struct LogOutResult :public DataHeader
{
    LogOutResult()
    {
        dataLength = sizeof(LogOutResult);
        cmd = CMD_LOGOUT_RET;
        ret = 1;
    }
    int ret;

};

struct NewUserJoin :public DataHeader
{
    NewUserJoin()
    {
        dataLength = sizeof(NewUserJoin);
        cmd = CMD_NEW_USER_JOIN;
        sock = -1;
    }
    int sock;
};

#endif

 

 

EasyTcpClient.hpp

#ifndef _EasyTcpClient_hpp_
#define _EasyTcpClient_hpp_

#ifdef _WIN32
    #include <windows.h>
    #include <WinSock2.h>
#else
    #include<unistd.h>
    #include<arpa/inet.h>
    #include<string.h>
    #define SOCKET int
    #define INVALID_SOCKET (SOCKET)(~0)
    #define SOCKET_ERROR (-1)
#endif

#include <stdio.h>
#include "DataHeader.hpp"

#define RECV_BUFF_SIZE 10240

class  EasyTcpClient
{
public:
    EasyTcpClient()
    {
        _sock = INVALID_SOCKET;
    }
    //虚析构函数
    virtual ~EasyTcpClient()
    {
        Close();
    }

    //初始化socket
    void InitSocket()
    {
#ifdef _WIN32
        WORD ver = MAKEWORD(2, 2);
        WSADATA dat;
        WSAStartup(ver, &dat);
#endif // _WIN32

        if (_sock != INVALID_SOCKET)
        {
            Close();
        }

        _sock = socket(AF_INET, SOCK_STREAM, 0);
        if (INVALID_SOCKET == _sock)
        {
            printf("错误，建立Socket失败...\n");
        }
        else
        {
            printf("建立Socket成功...\n");
        }

    }

    int Connect(const char* ip, unsigned short port)
    {
        if (INVALID_SOCKET == _sock)
        {
            InitSocket();
        }

        sockaddr_in _sin = {};
        _sin.sin_family = AF_INET;
        _sin.sin_port = htons(port);
#ifdef _WIN32
        _sin.sin_addr.S_un.S_addr = inet_addr(ip);
#else
        _sin.sin_addr.s_addr = inet_addr(ip);
#endif

        int ret = connect(_sock, (const sockaddr*)&_sin, sizeof(sockaddr_in));
        if (SOCKET_ERROR == ret)
        {
            printf("错误，连接服务端失败...\n");
        }
        else
        {
            printf("连接服务端成功...\n");
        }

        return ret;
    }

    bool isRun()
    {
        return (_sock != INVALID_SOCKET);
    }

    bool onRun()
    {
        if (isRun())
        {
            fd_set fdRead;
            FD_ZERO(&fdRead);
            FD_SET(_sock, &fdRead);

            timeval t = { 1, 0 };
            int ret = select(_sock + 1, &fdRead, 0, 0, &t);
            if (ret < 0)
            {
                Close();
                printf("select任务结束1。\n");
                return false;
            }

            if (FD_ISSET(_sock, &fdRead))
            {
                if (-1 == RecvData())
                {
                    Close();
                    printf("select任务结束2。\n");
                    return false;
                }
            }

        }
        return false;
    }

    //接收数据 处理粘包 拆分包
    int RecvData()
    {
        int nLen = recv(_sock, _szRecv, RECV_BUFF_SIZE, 0);
        //printf("nLen=%d\n", nLen);
        if (nLen <= 0)
        {
            printf("服务端%d已退出。\n", _sock);
            return -1;
        }

        //将收到的数据拷贝到消息缓冲区
        memcpy(_szMsgBuf + _lastPos, _szRecv, nLen);
        //消息缓冲区的数据尾部位置后移
        _lastPos += nLen;

        //判断消息缓冲区的数据长度大于消息头DataHeader长度
        while (_lastPos >= sizeof(DataHeader))
        {
            //这时就可以知道当前消息的长度
            DataHeader* header = (DataHeader*)_szMsgBuf;
            //判断是否可以获取一个完整消息
            if (_lastPos >= header->dataLength)
            {
                //剩余的未处理消息缓冲区数据的长度
                int nSize = _lastPos - header->dataLength;
                //处理网络消息
                onNetMsg(header);
                //将消息缓冲区剩余未处理数据前移
                memcpy(_szMsgBuf, _szMsgBuf + header->dataLength, nSize);
                //将消息缓冲区的数据尾部位置前移
                _lastPos = nSize;
            }
            else
            {
                //消息缓冲区剩余数据不够一条完整消息
                break;
            }
        }

        return 0;
    }

    void onNetMsg(DataHeader* pData)
    {
        switch (pData->cmd)
        {
        case CMD_LOGIN_RET:
        {
            LoginResult *pLogin = (LoginResult*)pData;
            //printf("login result:%d\n", pLogin->ret);
        }
        break;
        case CMD_LOGOUT_RET:
        {
            LogOutResult *pLogOut = (LogOutResult*)pData;
            printf("log out result:%d\n", pLogOut->ret);
        }
        break;
        case CMD_NEW_USER_JOIN:
        {
            NewUserJoin *pMsg = (NewUserJoin*)pData;
            printf("new user:%d join.\n", pMsg->sock);
        }
        break;
        case CMD_ERROR:
        {
            printf("收到服务端消息:CMD_ERROR，数据长度:%d\n", pData->dataLength);
        }
        break;
        default:
        {
            printf("收到未定义消息，数据长度:%d\n", pData->dataLength);
        }
        }
    }

    //发送数据
    int SendData(DataHeader* pHeader)
    {
        if (isRun() && pHeader)
        {
            return send(_sock, (const char*)pHeader, pHeader->dataLength, 0);
        }
        return SOCKET_ERROR;
    }

    void Close()
    {
        if (_sock != INVALID_SOCKET)
        {
#ifdef _WIN32
            closesocket(_sock);
            //清除Windows socket环境
            WSACleanup();
#else
            close(_sock);
#endif
            _sock = INVALID_SOCKET;
        }
    }

private:
    SOCKET _sock;

    //接收缓冲区
    char _szRecv[RECV_BUFF_SIZE] = {};

    //第二缓冲区 消息缓冲区
    char _szMsgBuf[RECV_BUFF_SIZE * 10] = {};

    //消息缓冲区的数据尾部位置
    int _lastPos = 0;

};


#endif

 

 

main.cpp

#ifdef  _WIN32
    #define WIN32_LEAN_AND_MEAN
    #define _WINSOCK_DEPRECATED_NO_WARNINGS //也可以放到工程属性，预处理中
    #define _CRT_SECURE_NO_WARNINGS
    #pragma comment(lib, "ws2_32.lib")
#endif 

#include <stdio.h>
#include <thread>
#include "EasyTcpClient.hpp"

bool g_bRun = true;
void cmdThread()
{
    while (true)
    {
        //3输入请求命令
        char cmdBuf[128] = {};
        scanf("%s", cmdBuf);
        getchar();
        //4处理请求
        if (0 == strcmp(cmdBuf, "exit"))
        {
            printf("退出cmdThread线程\n");
            return;
        }
        else
        {
            printf("wrong cmd, please input cmd again.\n");
        }
    }
}

int main()
{
    const int count = 100;
    EasyTcpClient* client[count];
    for (int n=0;n<count;n++)
    {
        client[n] = new EasyTcpClient();
        client[n]->Connect("192.168.10.157", 4567);
    }

    std::thread t(cmdThread);
    t.detach();

    Login login = {};
    strcpy(login.userName, "jj");
    strcpy(login.passWord, "ww");

    while (g_bRun)
    {
        for (int n = 0; n < count; n++)
        {
            client[n]->SendData(&login);
            client[n]->onRun();
        }

    }

    for (int n = 0; n < count; n++)
    {
        client[n]->Close();
    }

    for (int n = 0; n < count; n++)
    {
        delete client[n];
        client[n] = nullptr;
    }

    printf("已退出");
    getchar();
    return 0;
}

 

 

服务端-----------：

DataHeader.hpp

同客户端

 

EasyTcpServer.hpp

#ifndef _EasyTcpServer_hpp_
#define _EasyTcpServer_hpp_

#ifdef _WIN32
    #define FD_SETSIZE      1024
    #define WIN32_LEAN_AND_MEAN
    #define _WINSOCK_DEPRECATED_NO_WARNINGS //也可以放到工程属性，预处理中
    #define _CRT_SECURE_NO_WARNINGS
    #include <windows.h>
    #include <WinSock2.h>
    #pragma comment(lib, "ws2_32.lib")
#else
    #include<unistd.h>
    #include<arpa/inet.h>
    #include<string.h>
    #define SOCKET int
    #define INVALID_SOCKET (SOCKET)(~0)
    #define SOCKET_ERROR (-1)
#endif

#include <stdio.h>
#include <vector>
#include "DataHeader.hpp"

#define RECV_BUFF_SIZE 1024

class ClientSocket
{
public:
    ClientSocket(SOCKET sockfd = INVALID_SOCKET)
    {
        _sockfd = sockfd;
        //memset(_szMsgBuf, 0, sizeof(_szMsgBuf));
    }

    SOCKET sockfd()
    {
        return _sockfd;
    }

    char* msgBuf()
    {
        return _szMsgBuf;
    }

    int getlastPos()
    {
        return _lastPos;
    }

    void setlastPos(int pos)
    {
        _lastPos = pos;
    }

private:
    SOCKET _sockfd = INVALID_SOCKET;
    char _szMsgBuf[RECV_BUFF_SIZE * 10] = {};
    int _lastPos = 0;
};

class EasyTcpServer
{
public:
    EasyTcpServer()
    {
        _sock = INVALID_SOCKET;
    }

    virtual ~EasyTcpServer()
    {
        Close();
    }

    //初始化socket
    SOCKET InitSocket()
    {
#ifdef _WIN32
        WORD ver = MAKEWORD(2, 2);
        WSADATA dat;
        WSAStartup(ver, &dat);
#endif // _WIN32

        if (_sock != INVALID_SOCKET)
        {
            Close();
        }

        _sock = socket(AF_INET, SOCK_STREAM, 0);
        if (INVALID_SOCKET == _sock)
        {
            printf("错误，建立Socket失败...\n");
        }
        else
        {
            printf("建立Socket成功...\n");
        }

        return _sock;
    }

    //绑定端口号
    int Bind(const char* ip, unsigned short port)
    {
        sockaddr_in _sin = {};
        _sin.sin_family = AF_INET;
        _sin.sin_port = htons(4567);//host to net unsigned short

                                    //使用127.0.0.1可以防止外网访问
                                    //启用本机全部的ip地址可以使用，INADDR_ANY

#ifdef _WIN32
        if (ip)
        {
            _sin.sin_addr.S_un.S_addr = inet_addr(ip);
        }
        else
        {
            _sin.sin_addr.S_un.S_addr = INADDR_ANY;
        }

#else
        if (ip)
        {
            _sin.sin_addr.s_addr = inet_addr(ip);
        }
        else
        {
            _sin.sin_addr.s_addr = INADDR_ANY;
        }

#endif

        int ret = bind(_sock, (sockaddr*)&_sin, sizeof(sockaddr_in));
        if (SOCKET_ERROR == ret)
        {
            printf("错误，绑定网络端口失败...\n");
        }
        else
        {
            printf("绑定网络端口成功...\n");
        }

        return ret;
    }

    //监听端口号
    int Listen(int cnt)
    {
        int ret = listen(_sock, cnt);
        if (SOCKET_ERROR == ret)
        {
            printf("错误，监听网络端口失败...\n");
        }
        else
        {
            printf("监听网络端口成功...\n");
        }

        return ret;
    }

    //接收客户端连接
    int Accept()
    {
        sockaddr_in clientAddr = {};
        int nAddrLen = sizeof(clientAddr);
        SOCKET _cSock = INVALID_SOCKET;
#ifdef _WIN32
        _cSock = accept(_sock, (sockaddr*)&clientAddr, &nAddrLen);
#else
        _cSock = accept(_sock, (sockaddr*)&clientAddr, (socklen_t*)&nAddrLen);
#endif
        if (INVALID_SOCKET == _cSock)
        {
            printf("错误，接受到无效客户端socket...\n");
        }
        else
        {

            //NewUserJoin msg;
            //msg.sock = _cSock;
            //Send2All(&msg);

            _clients.push_back(new ClientSocket(_cSock));
            printf("新客户端加入:socket=%d,IP=%s,count=%d\n", _cSock, inet_ntoa(clientAddr.sin_addr), _clients.size());
        }

        return _cSock;
    }

    //关闭socket
    void Close()
    {
        if (_sock != INVALID_SOCKET)
        {
#ifdef _WIN32
            // 关闭套接字
            for (size_t n = 0; n<_clients.size(); n++)
            {
                closesocket(_clients[n]->sockfd());
                delete _clients[n];
            }
            closesocket(_sock);
            //清除Windows socket环境
            WSACleanup();
#else
            for (size_t n = 0; n<clients.size(); n++)
            {
                close(_clients[n]->sockfd());
                delete _clients[n];
            }
            close(_sock);
#endif

            _clients.clear();

        }

    }

    //处理网络消息
    bool OnRun()
    {
        if (!isRun())
        {
            return false;
        }

        fd_set fdRead;
        fd_set fdWrite;
        fd_set fdExp;

        FD_ZERO(&fdRead);
        FD_ZERO(&fdWrite);
        FD_ZERO(&fdExp);

        FD_SET(_sock, &fdRead);
        FD_SET(_sock, &fdWrite);
        FD_SET(_sock, &fdExp);

        SOCKET maxSock = _sock;
        for (size_t n = 0; n<_clients.size(); n++)
        {
            FD_SET(_clients[n]->sockfd(), &fdRead);
            if (maxSock < _clients[n]->sockfd())
            {
                maxSock = _clients[n]->sockfd();
            }
        }

        timeval t = { 1,0 };
        int ret = select(maxSock + 1, &fdRead, &fdWrite, &fdExp, &t);
        if (ret < 0)
        {
            printf("select任务结束。\n");
            Close();
            return false;
        }


        if (FD_ISSET(_sock, &fdRead))
        {
            FD_CLR(_sock, &fdRead);//从集合移除了_sock

            Accept();
        }


        for (int n = (int)_clients.size() - 1; n >= 0; n--)
        {
            if (FD_ISSET(_clients[n]->sockfd(), &fdRead))
            {
                if (-1 == RecvData(_clients[n]))
                {
                    auto iter = _clients.begin() + n;
                    if (iter != _clients.end())
                    {
                        delete _clients[n];
                        _clients.erase(iter);
                    }
                }
            }
        }

        return true;
    }

    //是否工作中
    bool isRun()
    {
        return _sock != INVALID_SOCKET;
    }


    //接收数据 处理粘包 拆分包
    int RecvData(ClientSocket* pClient)
    {

        // 接收客户端数据
        int nLen = (int)recv(pClient->sockfd(), _szRecv, RECV_BUFF_SIZE, 0);
        //printf("nLen=%d\n", nLen);
        if (nLen <= 0)
        {
            printf("客户端%d已退出。\n", pClient->sockfd());
            return -1;
        }

        memcpy(pClient->msgBuf() + pClient->getlastPos(), _szRecv, nLen);
        //消息缓冲区的数据尾部位置后移
        pClient->setlastPos(pClient->getlastPos() + nLen);


        //判断消息缓冲区的数据长度大于消息头DataHeader长度
        while (pClient->getlastPos() >= sizeof(DataHeader))
        {
            //这时就可以知道当前消息的长度
            DataHeader* header = (DataHeader*)pClient->msgBuf();
            //判断是否可以获取一个完整消息
            if (pClient->getlastPos() >= header->dataLength)
            {
                //剩余的未处理消息缓冲区数据的长度
                int nSize = pClient->getlastPos() - header->dataLength;
                //处理网络消息
                onNetMsg(pClient->sockfd(), header);
                //将消息缓冲区剩余未处理数据前移
                memcpy(pClient->msgBuf(), pClient->msgBuf() + header->dataLength, nSize);
                //将消息缓冲区的数据尾部位置前移
                pClient->setlastPos(nSize);
            }
            else
            {
                //消息缓冲区剩余数据不够一条完整消息
                break;
            }
        }

        return 0;
    }

    //响应网络消息
    virtual void onNetMsg(SOCKET _cSock, DataHeader* header)
    {
        switch (header->cmd)
        {
        case CMD_LOGIN:
        {
            Login *pLogin = (Login*)header;
            //printf("客户端%d,cmd logint,user:%s,password:%s\n", _cSock, pLogin->userName, pLogin->passWord);
            //----------------------------
            //----------------------------
            LoginResult longinRet = {};
            Send(_cSock, &longinRet);
        }
        break;
        case CMD_LOGOUT:
        {

            LogOut *pLogOut = (LogOut*)header;
            printf("客户端%d,cmd logout,user:%s\n", _cSock, pLogOut->userName);
            //----------------------------
            LogOutResult logOutRet = {};
            Send(_cSock, &logOutRet);
        }
        break;
        default:
        {
            DataHeader header = {};
            header.cmd = CMD_ERROR;
            Send(_cSock, &header);
        }
        break;
        }
    }

    //指定socket发送数据
    int Send(SOCKET _cSock, DataHeader* header)
    {
        if (isRun() && header)
        {
            return send(_cSock, (const char*)header, header->dataLength, 0);
        }
        return SOCKET_ERROR;
    }

    void Send2All(DataHeader* header)
    {
        if (isRun() && header)
        {
            for (int n = (int)_clients.size() - 1; n >= 0; n--)
            {
                Send(_clients[n]->sockfd(), header);
            }
        }

    }


private:
    SOCKET _sock;
    std::vector<ClientSocket*> _clients;
    char _szRecv[RECV_BUFF_SIZE] = {};

};

#endif

 

 

main.cpp

#ifdef  _WIN32
    #define WIN32_LEAN_AND_MEAN
    #define _WINSOCK_DEPRECATED_NO_WARNINGS //也可以放到工程属性，预处理中
    #define _CRT_SECURE_NO_WARNINGS
    #pragma comment(lib, "ws2_32.lib")
#endif 

#include <stdio.h>
#include <thread>
#include "EasyTcpClient.hpp"

bool g_bRun = true;
void cmdThread()
{
    while (true)
    {
        //3输入请求命令
        char cmdBuf[128] = {};
        scanf("%s", cmdBuf);
        getchar();
        //4处理请求
        if (0 == strcmp(cmdBuf, "exit"))
        {
            printf("退出cmdThread线程\n");
            return;
        }
        else
        {
            printf("wrong cmd, please input cmd again.\n");
        }
    }
}

int main()
{
    const int count = 100;
    EasyTcpClient* client[count];
    for (int n=0;n<count;n++)
    {
        client[n] = new EasyTcpClient();
        client[n]->Connect("192.168.10.157", 4567);
    }

    std::thread t(cmdThread);
    t.detach();

    Login login = {};
    strcpy(login.userName, "jj");
    strcpy(login.passWord, "ww");

    while (g_bRun)
    {
        for (int n = 0; n < count; n++)
        {
            client[n]->SendData(&login);
            client[n]->onRun();
        }

    }

    for (int n = 0; n < count; n++)
    {
        client[n]->Close();
    }

    for (int n = 0; n < count; n++)
    {
        delete client[n];
        client[n] = nullptr;
    }

    printf("已退出");
    getchar();
    return 0;
}