Minor spec and backwards compatibility fix

2 files changed, 31 insertions, 7 deletions

diff --git a/lib/diameter/src/base/diameter_peer.erl b/lib/diameter/src/base/diameter_peer.erl
index bfd59bee8e..a2a1c567d8 100644
--- a/lib/diameter/src/base/diameter_peer.erl
+++ b/lib/diameter/src/base/diameter_peer.erl
@@ -33,6 +33,9 @@
          abort/1,
          notify/2]).
 
+%% Old interface only called from old code.
+-export([start/3]).  %% < diameter-1.2 (R15B02)
+
 %% Server start.
 -export([start_link/0]).
 
@@ -70,9 +73,30 @@ notify(SvcName, T) ->
     rpc:abcast(nodes(), ?SERVER, {notify, SvcName, T}).
 
 %%% ---------------------------------------------------------------------------
+%%% # start/3
+%%% ---------------------------------------------------------------------------
+
+%% From old code: make is restart.
+start(_T, _Opts, #diameter_service{}) ->
+    {error, restart}.
+
+%%% ---------------------------------------------------------------------------
 %%% # start/1
 %%% ---------------------------------------------------------------------------
 
+-spec start({T, [Opt], #diameter_service{}})
+   -> {TPid, [Addr], Tmo, Data}
+    | {error, [term()]}
+ when T    :: {connect|accept, diameter:transport_ref()},
+      Opt  :: diameter:transport_opt(),
+      TPid :: pid(),
+      Addr :: inet:ip_address(),
+      Tmo  :: non_neg_integer(),
+      Data :: {{T, Mod, Cfg}, [Mod], [{T, [Mod], Cfg}], [Err]},
+      Mod  :: module(),
+      Cfg  :: term(),
+      Err  :: term().
+
 %% Initial start.
 start({T, Opts, #diameter_service{} = Svc}) ->
     start(T, Svc, pair(Opts, [], []), []);
@@ -132,13 +156,8 @@ def(Acc) ->
 start(T, Svc, [{Ms, Cfg, Tmo} | Rest], Errs) ->
     start(T, Ms, Cfg, Svc, Tmo, Rest, Errs);
 
-%% One transport: return the bare error for backwards compatibility.
-start(_, _, [], [Err]) ->
-    {Err};
-
-%% Or not: return list of errors.
 start(_, _, [], Errs) ->
-    {{error, Errs}}.
+    {error, Errs}.
 
 %% start/7
 
diff --git a/lib/diameter/src/base/diameter_peer_fsm.erl b/lib/diameter/src/base/diameter_peer_fsm.erl
index d5e2d690cf..638d905195 100644
--- a/lib/diameter/src/base/diameter_peer_fsm.erl
+++ b/lib/diameter/src/base/diameter_peer_fsm.erl
@@ -121,6 +121,11 @@
 %%% Output: Pid
 %%% ---------------------------------------------------------------------------
 
+-spec start(T, [Opt], #diameter_service{})
+   -> pid()
+ when T   :: {connect|accept, diameter:transport_ref()},
+      Opt :: diameter:transport_opt().
+
 %% diameter_config requires a non-empty list of applications on the
 %% service but diameter_service then constrains the list to any
 %% specified on the transport in question. Check here that the list is
@@ -179,7 +184,7 @@ start_transport(Addrs0, T) ->
             erlang:monitor(process, TPid),
             q_next(TPid, Addrs0, Tmo, Data),
             {TPid, addrs(Addrs, Addrs0)};
-        {No} ->
+        No ->
             exit({shutdown, No})
     end.