第15章 Unix域协议

#include <sys/un.h>

struct sockaddr_un
{
sa_family_t  sun_family;    /*  AF_LOCAL  */
char         sun_path[104]; /*可能是92~108*/
};

#include <sys/socket.h>

//创建两个连接起来的Unix域套接字
int socketpair(int family/*AF_LOCAL*/, int type, int protocol/*0*/, int sockfd[2]);//SOCK_STREAM创建全双工的流管道

#include "../Gnet.h"

void do_client(int connfd)
{
    char buf[MAX_LINE];

    while(fgets(buf, MAX_LINE, stdin) != NULL)
    {
        Write(connfd, buf, strlen(buf));
        memset(buf, 0, MAX_LINE);
        if(Read(connfd, buf, MAX_LINE) == 0)
            perr_exit("server terminated.\n");
        fputs(buf, stdout);
    }
}

int main(int argc, const char* argv[])
{
    int connfd;
    struct sockaddr_un server_addr;

    connfd = Socket(AF_LOCAL, SOCK_STREAM, 0);
    memset(&server_addr, 0, sizeof(server_addr));
    server_addr.sun_family = AF_LOCAL;
    strcpy(server_addr.sun_path, LOCAL_STRPATH);
    Connect(connfd, (struct sockaddr*)&server_addr, sizeof(server_addr));

    do_client(connfd);

    return 0;
}

#include "../Gnet.h"

void do_server(int connfd)
{
    ssize_t nread;
    char buf[MAX_LINE];

    while((nread = Read(connfd, buf, MAX_LINE)) > 0)
        Write(connfd, buf, nread);
}

void sig_child(int signo)
{
    pid_t pid;
    int stat;

    printf("in sig_child.\n");
    while((pid = waitpid(-1,&stat, WNOHANG)) > 0)
        printf("child %d terminated\n", pid);
    printf("out sig_child.\n");
}

int main(int argc, const char* argv[])
{
    int lfd, connfd;
    struct sockaddr_un server_addr, client_addr;
    socklen_t client_addr_len;
    pid_t child_id;

    struct sigaction sigaction_set, sigaction_get;
    sigaction_set.sa_handler = sig_child;
    sigemptyset(&sigaction_set.sa_mask);
    sigaction_set.sa_flags = 0;
    if(sigaction(SIGCHLD, &sigaction_set, &sigaction_get) <0)
        printf("sigaction(SIGCHLD) error!\n");

    memset(&server_addr, 0, sizeof(server_addr));
    unlink(LOCAL_STRPATH);//bind之前删除路径名
    server_addr.sun_family = AF_LOCAL;
    strcpy(server_addr.sun_path, LOCAL_STRPATH);

    lfd = Socket(AF_LOCAL, SOCK_STREAM, 0);
    Bind(lfd, (const struct sockaddr*)&server_addr, sizeof(server_addr));
    Listen(lfd, LISTENQ);

    while(1)
    {
        client_addr_len = sizeof(client_addr_len);
        connfd = Accept(lfd, (struct sockaddr*)&client_addr, &client_addr_len);

        if((child_id = fork()) == 0)//子进程
        {
            Close(lfd);
            do_server(connfd);
            Close(connfd);
            exit(0);
        }
        else//父进程
        {
            printf("child %d connected\n", child_id);
            Close(connfd);
        }
    }

    return 0;
}

#include "../Gnet.h"

void do_client(int udpfd, struct sockaddr* pserver_addr, socklen_t server_addr_len)
{
    char buf[MAX_LINE];
    int nread;

    while(fgets(buf, MAX_LINE, stdin) != NULL)
    {
        sendto(udpfd, buf, strlen(buf), 0, pserver_addr, server_addr_len);
        nread = recvfrom(udpfd, buf, MAX_LINE, 0, NULL, NULL);
        fputs(buf, stdout);
    }
}

int main(int argc, const char* argv[])
{
    int sockfd;
    struct sockaddr_un server_addr, client_addr;

    sockfd = Socket(AF_LOCAL, SOCK_DGRAM, 0);
    memset(&client_addr, 0, sizeof(client_addr));
    client_addr.sun_family = AF_LOCAL;
    strcpy(client_addr.sun_path, tmpnam(NULL));
    Bind(sockfd, (struct sockaddr*)&client_addr, sizeof(client_addr));

    memset(&server_addr, 0, sizeof(server_addr));
    server_addr.sun_family = AF_LOCAL;
    strcpy(server_addr.sun_path, LOCAL_STRPATH);

    do_client(sockfd, (struct sockaddr*)&server_addr, sizeof(server_addr));

    return 0;
}

#include "../Gnet.h"

void do_server(int udpfd)
{
    ssize_t nread;
    char buf[MAX_LINE];
    struct sockaddr_un client_addr;
    socklen_t client_addr_len;

    while(1)
    {
        client_addr_len = sizeof(client_addr);
        nread = recvfrom(udpfd, buf, MAX_LINE, 0, (struct sockaddr*)&client_addr, &client_addr_len);
        sendto(udpfd, buf, nread, 0, (struct sockaddr*)&client_addr, client_addr_len);
    }
}

int main(int argc, const char* argv[])
{
    int udpfd;
    struct sockaddr_un server_addr;

    memset(&server_addr, 0, sizeof(server_addr));
    server_addr.sun_family = AF_LOCAL;
    strcpy(server_addr.sun_path, LOCAL_STRPATH);

    udpfd = Socket(AF_LOCAL, SOCK_DGRAM, 0);
    unlink(LOCAL_STRPATH);
    Bind(udpfd, (const struct sockaddr*)&server_addr, sizeof(server_addr));
    printf("waiting for connecting.\n");

    do_server(udpfd);

    return 0;
}