QDnsLookup: add TimeoutError for timeouts

We were getting InvalidReplyError because it was simply unknown, which
is not very useful. Previously, the Unix code used res_nquery(), which
does not return timeouts as a condition. It returns -1 if a timeout did
happen, but the content in errno could be a left-over from a previous
timeout (see the "Not a typewriter"[1] problem).

With the rewrite to using res_nmkquery() and res_nsend() from the
previous commits, we can rely on errno being set properly by
res_nsend().

$ $objdir/tests/manual/qdnslookup/qdnslookup @0.0.0.1
; <<>> QDnsLookup 6.6.0 <<>> qdnslookup @0.0.0.1
;; status: TimeoutError (Request timed out)
;; QUESTION:
;qt-project.org                 IN A

;; Query time: 10008 ms
;; SERVER: 0.0.0.1#53

Tested on FreeBSD, Linux, macOS, and Windows.

[1] https://en.wikipedia.org/wiki/Not_a_typewriter

Change-Id: I3e3bfef633af4130a03afffd175e31958247f9b1
Reviewed-by: Mårten Nordheim <marten.nordheim@qt.io>

1 files changed, 2 insertions, 1 deletions

diff --git a/tests/auto/network/kernel/qdnslookup/tst_qdnslookup.cpp b/tests/auto/network/kernel/qdnslookup/tst_qdnslookup.cpp
index 4e2a5397a3..d923a0973f 100644
--- a/tests/auto/network/kernel/qdnslookup/tst_qdnslookup.cpp
+++ b/tests/auto/network/kernel/qdnslookup/tst_qdnslookup.cpp
@@ -328,7 +328,8 @@ void tst_QDnsLookup::lookup()
     };
 
     if (!dnsServersMustWork && (lookup.error() == QDnsLookup::ServerFailureError
-                                || lookup.error() == QDnsLookup::ServerRefusedError)) {
+                                || lookup.error() == QDnsLookup::ServerRefusedError
+                                || lookup.error() == QDnsLookup::TimeoutError)) {
         // It's not a QDnsLookup problem if the server refuses to answer the query.
         // This happens for queries of type ANY through Dnsmasq, for example.
         qWarning("Server refused or was unable to answer query; %s", extraErrorMsg().constData());