if the NSLIST already has a candidate with addresses, never replace
current leader with an empty one. otherwise if the former leader address
was tried and failed, new empty leader would be blamed for this and
penalized

policy has policy.todnames() for table of names

refs #33

refs #33

this fixes a bug when NS drops out of cache, but it's TA not,
so i.e. we end up with TA 'cz' and NS in '.', but we need the root TA

bad control flow, the zone cut should be checked for root, as the second
condition checks if SNAME is at/below cut so the outcome is the same for
root query

the copy doesn't take cdata length into account, but measures string len

refs #43

refs #43

this fixes a bug when a text-declared type wasn’t reused and LJ eventually segfaulted in ffi.new after a lot of redeclarations

the current Go doesn’t support c-shared on other architectures than amd64

fixes #42

fixes #41

this module allows to rewrite address ranges in answers to different address ranges specified in configuration

this allows daemon to try other NSs for fast retransmit if the best chosen NS doesn’t respond within time limit

instead of single I/O request per step, the daemon now retries
all addresses in the selection with 300ms timeout between tries.
there are len(list) + len(list)/2 tries

the idea is to reduce latency when UDP request doesn't punch through,
or some NSs are overwhelmed/faulty

RRs may be touched after resolution completion, this copies RR from
temporary per-recv buffer to answer, which is persistent for the whole
duration of request