Add support default port in /etc/resolver/* files

[nuxlli]

No description provided.

[bAndie91]

It would be useful to assume default port to be 53, not 65535.

[nuxlli]

@bAndie91 the example added after instalation (/etc/resolver/default.dev) is for port 53(nameserver 127.0.0.1) and for port 5353 (nameserver 192.168.50.1). You can check this at: https://github.com/azukiapp/libnss-resolver/blob/master/src%2Fsamples%2Fetc%2Fresolver%2Fdefault.dev

I've created this issue just as a reminder to add support for the contracted form (nameserver host), using port 53 as you pointed. Even this is present in the sample file, it's not possible yet due to a limitation of the c-ares lib, which we use to resolve the requests.

Thank you for your concern!

[petterreinholdtsen]

I suspect the problem you experience is because nssrs_resolver_by_servers() to not initialize all fields in options struct, specifically options.tcp_port and options.udp_port. If you initialize them to 53, the port used will be 53.