this_update

static VALUE
ossl_ocspsres_get_this_update(VALUE self)
{
    OCSP_SINGLERESP *sres;
    int status;
    ASN1_GENERALIZEDTIME *time;

    GetOCSPSingleRes(self, sres);
    status = OCSP_single_get0_status(sres, NULL, NULL, &time, NULL);
    if (status < 0)
        ossl_raise(eOCSPError, "OCSP_single_get0_status");
    if (!time)
        return Qnil;

    return asn1time_to_time(time);
}