unix文件通信

在unix文件通信中,如果设置了UNIX_ABSTRACT为1,那么unix通信文件不会在路径目录下显示出来,
如果设置UNIX_ABSTRACT为0,那么unix通信文件将会在路径目录下显示[luther.gliethttp]

头文件unix_abstract.h

#define UNIX_ABSTRACT 1

unix server源码

#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include <sys/socket.h>
#include <sys/un.h>
#include <unistd.h>
#include "unix_abstract.h"

#define DBG_LOG(msg...) printf(msg)

int accept_client(int listen_fd);

int main(void)
{
    int listen_fd;
    size_t path_len;
    struct sockaddr_un addr;
    char *path = "./luther.gliethttp";

    if ((listen_fd = socket(PF_UNIX, SOCK_STREAM, 0)) < 0) {
        DBG_LOG("socket: %s\n", strerror(errno));
        exit(-1);
    }
    
    memset(&addr, '\0', sizeof (addr));
    addr.sun_family = AF_UNIX;
    path_len = strlen (path);
    
    #if UNIX_ABSTRACT
    addr.sun_path[0] = '\0';
    path_len++;
    strncpy(&addr.sun_path[1], path, path_len);
    #else
    strncpy(&addr.sun_path[0], path, path_len);
    unlink(path);
    #endif

    if (bind(listen_fd, (struct sockaddr*)&addr, sizeof(addr)) < 0) {
        DBG_LOG("bind: %s\n", strerror(errno));
        exit(-1);
    }
    
    if (listen (listen_fd, 30) < 0) {
        DBG_LOG("listen: %s\n", strerror(errno));
        exit(-1);
    }

    DBG_LOG("OK\n");

    for (;;) {
        int client_fd;
        
        if ((client_fd = accept_client(listen_fd)) < 0) {
            DBG_LOG("accept_client: %s\n", strerror(errno));
        }

        DBG_LOG("client=%d\n", client_fd);

        sleep(1);
    }
    return 0;
}

int accept_client(int listen_fd)
{
    int client_fd;
    struct sockaddr addr;
    socklen_t addrlen;

    addrlen = sizeof (addr);
  
    retry:
        client_fd = accept(listen_fd, &addr, &addrlen);
        
        if (client_fd < 0) {
            if (errno == EINTR)
            goto retry;
        }
  
    return client_fd;
}

client端源码

#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include <sys/socket.h>
#include <sys/un.h>
#include "unix_abstract.h"

#define DBG_LOG(msg...) printf(msg)

int main(void)
{
    int unix_fd;
    size_t path_len;
    struct sockaddr_un addr;
    char *path = "./luther.gliethttp";

    if ((unix_fd = socket(PF_UNIX, SOCK_STREAM, 0)) < 0) {
        DBG_LOG("socket: %s\n", strerror(errno));
        exit(-1);
    }
    
    memset(&addr, '\0', sizeof (addr));
    addr.sun_family = AF_UNIX;
    path_len = strlen (path);
    
    #if UNIX_ABSTRACT
    addr.sun_path[0] = '\0';
    path_len++;
    strncpy(&addr.sun_path[1], path, path_len);
    #else
    strncpy(&addr.sun_path[0], path, path_len);
    #endif
    
    if (connect(unix_fd, (struct sockaddr*)&addr, sizeof(addr)) < 0) {
        DBG_LOG("connect: %s\n", strerror(errno));
        exit(-1);
    }

    DBG_LOG("OK\n");

    for (;;) {
        char buf[10];
        static int serial = 0;
        sprintf(buf, "%d", serial++);
        write(unix_fd, buf, strlen(buf));
        sleep(1);
    }
    return 0;
}

int accept_client(int listen_fd)
{
    int client_fd;
    struct sockaddr addr;
    socklen_t addrlen;

    addrlen = sizeof (addr);
  
    retry:
        client_fd = accept(listen_fd, &addr, &addrlen);
        
        if (client_fd < 0) {
            if (errno == EINTR)
            goto retry;
        }
  
    return client_fd;
}

luther@gliethttp:~$ gcc -o unix_socket unix_socket.c
luther@gliethttp:~$ gcc -o unix_socket_client unix_socket_client.c
luther@gliethttp:~$ ./unix_socket
OK
client=4
luther@gliethttp:~$ ./unix_socket_client
OK