sldns_b32_pton_calculate_size
size_t sldns_b32_pton_calculate_size(size_t src_text_length);
size_t sz = sldns_b32_pton_calculate_size(slen);
size_t sldns_b32_pton_calculate_size(size_t src_text_length);
size_t sz = sldns_b32_pton_calculate_size(slen);