cert_list
VECTOR(br_x509_certificate) cert_list = VEC_INIT;
VEC_ADD(cert_list, xc);
if (VEC_LEN(cert_list) == 0) {
*num = VEC_LEN(cert_list);
VEC_ADD(cert_list, dummy);
xcs = VEC_TOARRAY(cert_list);
VEC_CLEAR(cert_list);
cert_list chain = VEC_INIT;