How can I test a function with void return value when using cunit

I have a function that I need to test with cunit. The function looks like this:

void server(unsigned short port) {
    int sock_fd = socket(AF_INET, SOCK_STREAM, 0);
    if (sock_fd < 0) {
        perror("server: socket");
        exit(1);
    }

    struct sockaddr_in server;
    server.sin_family = AF_INET;
    server.sin_port = htons(port);
    server.sin_addr.s_addr = INADDR_ANY;

    memset(&server.sin_zero, 0, 8);

    if (bind(sock_fd, (struct sockaddr *)&server, sizeof(server)) < 0) {
        perror("server: bind");
        close(sock_fd);
        exit(1);
    }

    if (listen(sock_fd, MAX_BACKLOG) < 0) {
        perror("server: listen");
        close(sock_fd);
        exit(1);
    }
    ......
}

How can I test this function using cunit?