resolved: remember explicitly whether we already tried a stream connection

poettering · poettering · commit cbe4216dd1b7 · 2015-12-27T01:41:39.000+01:00
On LLMNR we never want to retry stream connections (since local TCP
connections should work, and we don't want to unnecessarily delay
operation), explicitly remember whether we already tried one, instead of
deriving this from a still stored stream object. This way, we can free
the stream early, without forgetting that we tried it.
diff --git a/src/resolve/resolved-dns-transaction.c b/src/resolve/resolved-dns-transaction.c
@@ -421,6 +421,8 @@ static int dns_transaction_open_tcp(DnsTransaction *t) {
         if (t->scope->link)
                 t->stream->ifindex = t->scope->link->ifindex;
 
+        t->tried_stream = true;
+
         return 0;
 }
 
@@ -826,21 +828,18 @@ static usec_t transaction_get_resend_timeout(DnsTransaction *t) {
 }
 
 static int dns_transaction_prepare(DnsTransaction *t, usec_t ts) {
-        bool had_stream;
         int r;
 
         assert(t);
 
-        had_stream = !!t->stream;
-
         dns_transaction_stop(t);
 
         if (t->n_attempts >= TRANSACTION_ATTEMPTS_MAX(t->scope->protocol)) {
                 dns_transaction_complete(t, DNS_TRANSACTION_ATTEMPTS_MAX_REACHED);
                 return 0;
         }
 
-        if (t->scope->protocol == DNS_PROTOCOL_LLMNR && had_stream) {
+        if (t->scope->protocol == DNS_PROTOCOL_LLMNR && t->tried_stream) {
                 /* If we already tried via a stream, then we don't
                  * retry on LLMNR. See RFC 4795, Section 2.7. */
                 dns_transaction_complete(t, DNS_TRANSACTION_ATTEMPTS_MAX_REACHED);
diff --git a/src/resolve/resolved-dns-transaction.h b/src/resolve/resolved-dns-transaction.h
@@ -69,6 +69,8 @@ struct DnsTransaction {
 
         uint16_t id;
 
+        bool tried_stream:1;
+
         bool initial_jitter_scheduled:1;
         bool initial_jitter_elapsed:1;
 
