From fc510c07a1e9879f176824cf91fab1a8ba1ec4c5 Mon Sep 17 00:00:00 2001
From: Hans Svensson <hans.svensson@quviq.com>
Date: Tue, 17 Apr 2018 09:00:22 +0200
Subject: [PATCH] Handle errors in start_link (tcp_closed)

---
 src/enoise.erl            |  6 ++++--
 src/enoise_connection.erl | 16 ++++++++++------
 2 files changed, 14 insertions(+), 8 deletions(-)

diff --git a/src/enoise.erl b/src/enoise.erl
index ad85251..0df59f3 100644
--- a/src/enoise.erl
+++ b/src/enoise.erl
@@ -237,8 +237,10 @@ tcp_handshake(TcpSock, Role, Options) ->
 
             case handshake(Options, Role, ComState) of
                 {ok, #{ rx := Rx, tx := Tx, final_state := FState }, #{ state := {_, _, Buf} }} ->
-                    {ok, Pid} = enoise_connection:start_link(TcpSock, Rx, Tx, self(), {Active, Buf}),
-                    {ok, #enoise{ pid = Pid }, FState};
+                    case enoise_connection:start_link(TcpSock, Rx, Tx, self(), {Active, Buf}) of
+                        {ok, Pid} -> {ok, #enoise{ pid = Pid }, FState};
+                        Err = {error, _} -> Err
+                    end;
                 Err = {error, _} ->
                     Err
             end;
diff --git a/src/enoise_connection.erl b/src/enoise_connection.erl
index a540a9f..e98a7ec 100644
--- a/src/enoise_connection.erl
+++ b/src/enoise_connection.erl
@@ -37,12 +37,16 @@ start_link(TcpSock, Rx, Tx, Owner, {Active0, Buf}) ->
                     tcp_sock = TcpSock, active = Active },
     case gen_server:start_link(?MODULE, [State], []) of
         {ok, Pid} ->
-            ok = gen_tcp:controlling_process(TcpSock, Pid),
-            %% Changing controlling process require a bit of
-            %% fiddling with already received and delivered content...
-            [ Pid ! {tcp, TcpSock, Buf} || Buf /= <<>> ],
-            flush_tcp(Pid, TcpSock),
-            {ok, Pid};
+            case gen_tcp:controlling_process(TcpSock, Pid) of
+                ok ->
+                    %% Changing controlling process require a bit of
+                    %% fiddling with already received and delivered content...
+                    [ Pid ! {tcp, TcpSock, Buf} || Buf /= <<>> ],
+                    flush_tcp(Pid, TcpSock),
+                    {ok, Pid};
+                Err = {error, _} ->
+                    Err
+            end;
         Err = {error, _} ->
             Err
     end.