static int addr_strings(const BIO_ADDR *ap, int numeric,
                        char **hostname, char **service)
{
    if (BIO_sock_init() != 1)
        return 0;

    if (1) {
#ifdef AI_PASSIVE
        int ret = 0;
        char host[NI_MAXHOST] = "", serv[NI_MAXSERV] = "";
        int flags = 0;

        if (numeric)
            flags |= NI_NUMERICHOST | NI_NUMERICSERV;

        if ((ret = getnameinfo(BIO_ADDR_sockaddr(ap),
                               BIO_ADDR_sockaddr_size(ap),
                               host, sizeof(host), serv, sizeof(serv),
                               flags)) != 0) {
# ifdef EAI_SYSTEM
            if (ret == EAI_SYSTEM) {
                SYSerr(SYS_F_GETNAMEINFO, get_last_socket_error());
                BIOerr(BIO_F_ADDR_STRINGS, ERR_R_SYS_LIB);
            } else
# endif
            {
                BIOerr(BIO_F_ADDR_STRINGS, ERR_R_SYS_LIB);
                ERR_add_error_data(1, gai_strerror(ret));
            }
            return 0;
        }

        /* VMS getnameinfo() has a bug, it doesn't fill in serv, which
         * leaves it with whatever garbage that happens to be there.
         * However, we initialise serv with the empty string (serv[0]
         * is therefore NUL), so it gets real easy to detect when things
         * didn't go the way one might expect.
         */
        if (serv[0] == '\0') {
            BIO_snprintf(serv, sizeof(serv), "%d",
                         ntohs(BIO_ADDR_rawport(ap)));
        }

        if (hostname)
            *hostname = OPENSSL_strdup(host);
        if (service)
            *service = OPENSSL_strdup(serv);
    } else {
#endif
        if (hostname)
            *hostname = OPENSSL_strdup(inet_ntoa(ap->sin.sin_addr));
        if (service) {
            char serv[6];        /* port is 16 bits => max 5 decimal digits */
            BIO_snprintf(serv, sizeof(serv), "%d", ntohs(ap->sin.sin_port));
            *service = OPENSSL_strdup(serv);
        }
    }

    return 1;
}