Repeat attempts to obtain the remote pidHEADmaster

Sometimes the function would find two pids instead of one,
likely due to timing issues related to reusing port numbers.
In these cases we retry up to 5 times with a short timeout
in between.

1 files changed, 14 insertions, 2 deletions

diff --git a/src/ct_helper.erl b/src/ct_helper.erl
index 5659f47..3723095 100644
--- a/src/ct_helper.erl
+++ b/src/ct_helper.erl
@@ -129,14 +129,26 @@ get_parent_pid(Pid) ->
 get_remote_pid_tcp(Socket) when is_port(Socket) ->
 	get_remote_pid_tcp(inet:sockname(Socket));
 get_remote_pid_tcp(SockName) ->
+	get_remote_pid_tcp(SockName, 5).
+
+get_remote_pid_tcp(SockName, 0) ->
+	AllPorts = [{P, erlang:port_info(P), (catch inet:peername(P))} || P <- erlang:ports()],
+	error({missing_or_duplicate_ports, SockName, AllPorts});
+get_remote_pid_tcp(SockName, Attempts) ->
 	AllPorts = [{P, erlang:port_info(P)} || P <- erlang:ports()],
-	[Pid] = [
+	Result = [
 		proplists:get_value(connected, I)
 	|| {P, I} <- AllPorts,
 		I =/= undefined,
 		proplists:get_value(name, I) =:= "tcp_inet",
 		inet:peername(P) =:= SockName],
-	Pid.
+	case Result of
+		[Pid] ->
+			Pid;
+		_ ->
+			timer:sleep(10),
+			get_remote_pid_tcp(SockName, Attempts - 1)
+	end.
 
 %% @doc Find the pid of the remote end of a TLS socket.
 %%