ASN1_GENERALIZEDTIME *ASN1_GENERALIZEDTIME_adj(ASN1_GENERALIZEDTIME *s,
                                               time_t t, int offset_day,
                                               long offset_sec)
{
    char *p;
    struct tm *ts;
    struct tm data;
    size_t len = 20;
    ASN1_GENERALIZEDTIME *tmps = NULL;

    if (s == NULL)
        tmps = ASN1_GENERALIZEDTIME_new();
    else
        tmps = s;
    if (tmps == NULL)
        return NULL;

    ts = OPENSSL_gmtime(&t, &data);
    if (ts == NULL)
        goto err;

    if (offset_day || offset_sec) {
        if (!OPENSSL_gmtime_adj(ts, offset_day, offset_sec))
            goto err;
    }

    p = (char *)tmps->data;
    if ((p == NULL) || ((size_t)tmps->length < len)) {
        p = OPENSSL_malloc(len);
        if (p == NULL) {
            ASN1err(ASN1_F_ASN1_GENERALIZEDTIME_ADJ, ERR_R_MALLOC_FAILURE);
            goto err;
        }
        OPENSSL_free(tmps->data);
        tmps->data = (unsigned char *)p;
    }

    sprintf(p, "%04d%02d%02d%02d%02d%02dZ", ts->tm_year + 1900,
            ts->tm_mon + 1, ts->tm_mday, ts->tm_hour, ts->tm_min,
            ts->tm_sec);
    tmps->length = strlen(p);
    tmps->type = V_ASN1_GENERALIZEDTIME;
#ifdef CHARSET_EBCDIC_not
    ebcdic2ascii(tmps->data, tmps->data, tmps->length);
#endif
    return tmps;
 err:
    if (s == NULL)
        ASN1_GENERALIZEDTIME_free(tmps);
    return NULL;
}