[PATCH] CYGWIN: Fix resolver debugging output

Corinna Vinschen corinna-cygwin@cygwin.com
Mon Feb 1 15:02:09 GMT 2021

On Feb  1 14:23, Lavrentiev, Anton (NIH/NLM/NCBI) [C] via Cygwin-patches wrote:
> > Please use %ls, %S is non-standard.
> Sure.
> > For instance, write_record appears to handle DNS_TYPE_A,
> > but not DNS_TYPE_AAAA.
> I can add that, it's not a problem.  But indeed, reparsing of Windows packets,
> does miss AAAA (as well as some other types, such as URI -- not sure if Windows
> has it, though).
> > Would you mind to split this into a patchset with patches for different
> > tasks?  ATM I'm a bit concerned about the ntoh{sl} calls, given the
> > noticable absence of IPv6 support...
> Okay.  BTW, I added ntol/s only for output of *nameserver*'s IPv4:port, because
> nameservers are IPv4 (even in glibc, AFAIK).  The _res structure (same in glibc)
> has these addresses as "struct in_addr", meaning they are IPv4.

But nameservers could be v6 addresses nevertheless, and the values are
stored in the _ext.nsaddrs member these days.  Our definition of
_res_state does not define all the members of _ext as GLibc defines,
though, and our resolver code doesn't use _ext at all, afaics.

> And so there's
> no risk of running into any troubles, but reading the IP addresses in debug output
> is much easier if they are in native order (and same goes for ports, even more).

Except, the value has no meaning for ipv6.


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