#include <sys/socket.h>
#include <sys/un.h>
#include <netinet/in.h>
#include <netdb.h>

#include <assert.h>

#include <stdlib.h>
#include <stdio.h>
#include <stddef.h>
#include <unistd.h>
#include <string.h>

void nameinfo(struct sockaddr *sa, socklen_t salen, char *prefix)
{
    char ntop[NI_MAXHOST];
    char strport[NI_MAXSERV];

    if (sa->sa_family == AF_UNIX) {
        struct sockaddr_un *sun = (struct sockaddr_un *)sa;
        socklen_t len = offsetof(struct sockaddr_un, sun_path);
        assert(salen >= len);
        // XXX: salen take '\0' into account
        sun->sun_path[salen - len] = '\0';
    }

    assert(!getnameinfo(sa, salen,
        ntop, sizeof(ntop),
        strport, sizeof(strport),
        NI_NUMERICHOST|NI_NUMERICSERV));

    printf("%ssocklen=%i, family=%i, host=%s, serv=%s\n",
        prefix, salen, sa->sa_family, ntop, strport);
}

int main()
{
    int fd;
    struct sockaddr_storage ss;
    struct sockaddr *sa = (struct sockaddr *)&ss;
    struct sockaddr_un *sun = (struct sockaddr_un *)&ss;
    socklen_t salen;

    puts("AF_UNIX:");
    fd = socket(AF_UNIX, SOCK_STREAM, 0);
    salen = sizeof(ss);
    assert(!getsockname(fd, sa, &salen));
    nameinfo(sa, salen, " ");

    puts(" bind():");
    memset(&ss, 0, sizeof(ss));
    sun->sun_family = AF_UNIX;
    strcpy(sun->sun_path, "/tmp/sock");
    unlink(sun->sun_path);
    salen = sizeof(*sun);
    assert(!bind(fd, sa, salen));
    assert(!getsockname(fd, sa, &salen));
    nameinfo(sa, salen, "  ");

    return 0;
}