MB-67804: Merge trinity into phoenix

o  MB-67804: Make sure cb_dist:select does not block net_kernel

Change-Id: I5f176dcbbc28598b7c45ff33024a5b2d7d61c20b

Author: timofey-barmin

apps/ns_server/src/cb_dist.erl

@@ -143,12 +143,18 @@ accept_connection(_, {ConRef, HandshakeProcPid, Module, ConnectionSocket},
 
 -spec select(Node :: atom()) -> true | false.
 select(Node) ->
-    try get_preferred_dist(Node) of
-        Module -> Module:select(Node)
-    catch
-        _:Error ->
-            error_msg("Select for ~p failed. Couldn't find preferred proto: ~p",
-                      [Node, Error]),
+    case dist_util:split_node(Node) of
+        {node, _Name, _Host} ->
+            %% Not proxying select() to preferred proto to avoid blocking
+            %% net_kernel (select() is called by net_kernel).
+            %% Select in inet_tcp_dist (and other protocols) can block
+            %% because it resolves the hostname.
+            %% It seems like the name resolution is not really needed here
+            %% as we already know the protocol (afamily and encryption) that
+            %% we want to use.
+            true;
+        _ ->
+            error_msg("Select failed. Invalid node name: ~p", [Node]),
             false
     end.