Linux中用C++架設基本TCP/IP server

這是在Linux中用C++以及Linux的system call
寫的一個基本的TCP/IP server
架設server的基本routine就是這樣而已
需要的時候就直接複製使用吧

下面是我寫的程式碼
程式碼解釋我哪天有空再來補(感覺是不會補了哈哈

//tcpserver.cpp
#include <iostream>
#include <string>
#include <cstring>
#include <sstream>
#include <unistd.h>
#include <sys/types.h>
#include <stdlib.h>
#include <signal.h>
#include <arpa/inet.h>
#include <netinet/in.h>
#include <sys/socket.h>  /*for BSD*/

struct socket_info{
        int sockfd;
        struct sockaddr_in      addr;
};

int serverTCP(std::string port){
        int                     sockfd;
        struct sockaddr_in      serv_addr;
        int SERV_TCP_PORT;
        std::stringstream ss;

        /*Open a TCP socket(an Internet stream socket).*/
        if((sockfd = socket(AF_INET, SOCK_STREAM, 0))<0)
                std::cerr << "server: can't open stream socket";

        /*Bind our lacal address so that the client can send to us*/
        ss.clear();
        ss.str(port);
        ss >> SERV_TCP_PORT;
        bzero((char *)&serv_addr, sizeof(serv_addr));
        serv_addr.sin_family = AF_INET;
        serv_addr.sin_addr.s_addr = htonl(INADDR_ANY);
        serv_addr.sin_port = htons(SERV_TCP_PORT);
        if(bind(sockfd, (struct sockaddr*)&serv_addr, sizeof(serv_addr))<0)
                std::cerr << "server: can't bind local address\n";
        /*listen*/
        listen(sockfd,5);

        return sockfd;
}

socket_info acceptTCP(int sockfd){
        struct sockaddr_in      cli_addr;
        socklen_t clilen;
        socket_info client_info; 

        clilen = sizeof(cli_addr);
        client_info.sockfd = accept(sockfd, (struct sockaddr*) &cli_addr, &clilen);
        client_info.addr = cli_addr;
        return client_info;       
}

void handleEachClient(int sockfd){
        dup2(sockfd,STDIN_FILENO);
        dup2(sockfd,STDOUT_FILENO);
        std::string str_read = "";
        while(1){
                std::getline(std::cin, str_read, '\n');
                std::cout << "server echo: " << str_read << std::endl;
        }
}

int main(int argc, char *argv[]){
        int sockfd, newsockfd;
        std::stringstream ss;
        std::string str_port = "";
        socket_info client;

        /*create main tcp server socket*/
        ss.clear();
        ss.str(argv[1]);
        ss >> str_port;
        sockfd = serverTCP(str_port);

        for(;;){
                client = acceptTCP(sockfd);
                std::cout << "newsockfd after accept = " << client.sockfd << std::endl;
                std::string client_ip = inet_ntoa(client.addr.sin_addr);
                std::cout << "client ip = " << client_ip << std::endl;
                int client_port = (int) ntohs(client.addr.sin_port);
                std::cout << "client port = " << client_port << std::endl;
                if(client.sockfd<0)
                        std::cerr << "server: accept error";
                signal(SIGCHLD,SIG_IGN);
                if(fork() == 0){ /*child process*/
                        signal(SIGCHLD,SIG_DFL);
                        close(sockfd);
                        handleEachClient(client.sockfd);
                        exit(0);
                }else{ /*parent process*/
                        close(newsockfd);
                }
        }
}

結果的截圖我就不放了
反正就是server

好了，今天的筆記到此結束
希望有幫助未來遺忘這些的自己，以及需要的人