伺服器端編程樣本

標籤：server

int fd_set_nonblock(int fd)

{

    int rv;

    rv = fcntl(fd, F_GETFL, 0);

    if(rv < 0){

    printf("fcntl error\n");

    return -1;

    }

    rv = fcntl(fd, F_SETFL, rv | O_NONBLOCK);

    if(rv < 0){

    printf("fcntl error\n");

    return -1;

    }

    return 0;

}

int init_server_socket()

{

    int fd;

    struct sockaddr_in addr;

    int ret;

    int v_on = 1;

    fd = socket(PF_INET, SOCK_STREAM, 0);

    if (fd < 0) {

    printf("server socket create failed\n");

    return -1;

    }

    ret = setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &v_on, sizeof (v_on));

    if (ret != 0) {

        printf("setsockopt error\n");

        goto out_close_socket;

    }

    memset(&addr, 0, sizeof(struct sockaddr_in));

    addr.sin_family = AF_INET;

    addr.sin_addr.s_addr=INADDR_ANY;

    addr.sin_port = htons(40000);

    ret = bind(fd,(struct sockaddr *)&addr,sizeof(addr));

    if (ret < 0) {

        printf("Server socket bind error\n");

        goto out_close_socket;

    }

    ret = listen(fd, 20);

    if (ret < 0) {

        printf("Server socket listen error\n");

        goto out_close_socket;

    }

    ret = fd_set_nonblock(fd);

    if(ret != 0){

        printf("fd_set_nonblock() failed\n");

        goto out_close_socket;

    }

    return fd;

out_close_socket:

    close(fd);

    return -1;

}

int main(int argc, char *argv[])

{

    int listenfd;

    int rv;

    listenfd = init_server_socket();

    if (listenfd < 0) {

    exit(1);

    }

    while(1){

        fd_set readfds;

        struct timeval t;

        int connfd;

        structsockaddr_in clientaddr;

        socklen_t addrlen;

        int r;

        FD_ZERO(&readfds);

        if(listenfd >= 0)FD_SET(listenfd, &readfds);

        t.tv_sec = 60;

        t.tv_usec = 0;

        r = select(listenfd+1, &readfds, NULL, NULL, &t);

        if(r == 0){

    continue;

        }

        if(r < 0){

            if(errno != EINTR)

        printf("signal caught\n");

    continue;

        }

        if(!FD_ISSET(listenfd, &readfds))

    continue;

        memset(&clientaddr, 0, sizeof(struct sockaddr_in));

        addrlen = sizeof(struct sockaddr_in);

        connfd = accept(listenfd,(struct sockaddr *)&clientaddr, &addrlen);

        if(connfd < 0){

    continue;

        }

        /**********背景工作執行緒**********/

    }

    close(listenfd);

    return 0;

}