resolv: fix resolver to return TRY_AGAIN on timeout

This fixes the internal __dns_lookup to get a h_errno pointer so
it works nicely with the _r variants. Additionally the function is
modified to permanent error if the static buffer lengths are not
enough. And finally it fixed to return TRY_AGAIN if the nameservers
timeout.

res_search is fixed to continue searching if we receive TRY_AGAIN.
It could be a problem with the specific search domain's server
and not necessarily a problem in the recursive resolver we are
querying. For same reason, it does not make sense to differentiate
timeout or SERVFAIL error reply.

The biggest issue this fixes is that we now properly set h_errno
to TRY_AGAIN if upstream nameserver(s) timed out. Previously we
would have returned NETDB_INTERNAL.

Signed-off-by: Timo Teräs <timo.teras@iki.fi>
Signed-off-by: Natanael Copa <ncopa@alpinelinux.org>

0 files changed, 0 insertions, 0 deletions