C++回声服务器_6-多进程pipe版本服务器

傷城~ 2022-03-06 03:36 148阅读 0赞

在服务器多进程版本的基础上，使用管道来向一个子进程发送接收到的数据，该子进程将接收到的数据保存到文件中。客户端代码不变。

## 服务器代码 ##

#include <cstdio>
    #include <cstdlib>
    #include <cstring>
    #include <unistd.h>
    #include <csignal>
    #include <sys/wait.h>
    #include <arpa/inet.h>
    #include <sys/socket.h>
    
    const int BUF_SIZE = 30;
    
    void error_handling(const char *messgae);
    void read_childproc(int sig);
    
    // 接收一个参数，argv[1]为端口号
    int main(int argc, char *argcv[]) {
        int server_sock, client_sock;
        struct sockaddr_in server_addr, client_addr;
        int fds[2]; // 管道描述符
    
        pid_t pid;
        struct sigaction act;
        socklen_t addr_size;
        int str_len, state;
        char buf[BUF_SIZE];
    
        if (argc != 2) {
            printf("Usgae : %s <port>\n", argcv[0]);
            exit(1);
        }
    
        act.sa_handler = read_childproc;
        sigemptyset(&act.sa_mask);
        act.sa_flags = 0;
        state = sigaction(SIGCHLD, &act, 0);
    
        server_sock = socket(PF_INET, SOCK_STREAM, 0);
        memset(&server_addr, 0, sizeof(server_addr));
        server_addr.sin_family = AF_INET;
        server_addr.sin_addr.s_addr = htonl(INADDR_ANY);
        server_addr.sin_port = htons(atoi(argcv[1]));
    
        if (bind(server_sock, (struct sockaddr*)&server_addr, sizeof(server_addr)) == -1) {
            error_handling("bind() error");
        }
    
        if (listen(server_sock, 5) == -1) {
            error_handling("listen() error");
        }
    
        pipe(fds);
        pid = fork();
        if (pid == 0) { // 负责保存数据到文件的子进程
            FILE *fp = fopen("echomsg.txt", "wt");
            char msgbuf[BUF_SIZE];
            int len;
    
            for (int i = 0; i < 10; ++i) {
                len = read(fds[0], msgbuf, BUF_SIZE);
                fwrite((void*)msgbuf, 1, len, fp);
            }
            fclose(fp);
            return 0;
        }
    
        while (1) {
            addr_size = sizeof(client_addr);
            client_sock =accept(server_sock, (struct sockaddr*)&server_addr, &addr_size);
            if (client_sock == -1) {
                continue;
            } else {
                puts("new client connected...");
            }
    
            pid = fork();
            if (pid == 0) {
                close(server_sock);
                while ((str_len = read(client_sock, buf, BUF_SIZE)) != 0) {
                    write(client_sock, buf, str_len);
                    write(fds[1], buf, str_len); // 发送数据给负责保存文件的子进程
                }
                close(client_sock);
                puts("client disconnected...");
                return 0;
            } else {
                close(client_sock);
            }
        }
    
        close(server_sock);
        return 0;
    }

## 项目代码 ##

[github][]

## 参考 ##

[《TCP/IP网络编程》][TCP_IP]

[github]: https://github.com/chenBright/Unix-Linux-Program/tree/master/echo_server/echo_multiprogress_pipe
[TCP_IP]: https://book.douban.com/subject/25911735/