zreceive
if (length_extra[z]) len += zreceive(a, length_extra[z]);
if (dist_extra[z]) dist += zreceive(a, dist_extra[z]);
int hlit = zreceive(a,5) + 257;
int hdist = zreceive(a,5) + 1;
int hclen = zreceive(a,4) + 4;
int s = zreceive(a,3);
c = zreceive(a,2)+3;
c = zreceive(a,3)+3;
c = zreceive(a,7)+11;
zreceive(a, a->num_bits & 7); // discard
final = zreceive(a,1);
type = zreceive(a,2);