#include <unistd.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/un.h>
#include <sys/wait.h>
#include <signal.h>
#include <errno.h>

#define A4_SOCK "./apr_accept4_test_socket"

int main()
{
    pid_t pid;
    int fd;
    struct sockaddr_un loc, rem;
    socklen_t rem_sz;

    if ((pid = fork())) {
        int status;

        unlink(A4_SOCK);

        if ((fd = socket(AF_UNIX, SOCK_STREAM, 0)) == -1)
            goto cleanup_failure2;

        loc.sun_family = AF_UNIX;
        strncpy(loc.sun_path, A4_SOCK, sizeof(loc.sun_path) - 1);

        if (bind(fd, (struct sockaddr *) &loc,
                 sizeof(struct sockaddr_un)) == -1)
            goto cleanup_failure;

        if (listen(fd, 5) == -1)
            goto cleanup_failure;

        rem_sz = sizeof(struct sockaddr_un);
        if (accept4(fd, (struct sockaddr *) &rem, &rem_sz, 0) == -1) {
            goto cleanup_failure;
        }
        else {
            close(fd);
            waitpid(pid, &status, 0);
            unlink(A4_SOCK);
            return 0;
        }

cleanup_failure:
        close(fd);
cleanup_failure2:
        kill(pid, SIGKILL);
        waitpid(pid, &status, 0);
        unlink(A4_SOCK);
        return 1;
    }
    else {
        if ((fd = socket(AF_UNIX, SOCK_STREAM, 0)) == -1)
            return 1; /* this will be bad: we'll hang */

        loc.sun_family = AF_UNIX;
        strncpy(loc.sun_path, A4_SOCK, sizeof(loc.sun_path) - 1);

        while(connect(fd, (struct sockaddr *) &loc,
                      sizeof(struct sockaddr_un)) == -1 &&
              (errno==ENOENT || errno==ECONNREFUSED))
            ;

        close(fd);
        return 0;
    }
}