Merge branch 'anders/diameter/decode/OTP-12871' into maint-17

* anders/diameter/decode/OTP-12871:
  Don't traverse errors list unnecessarily when detecting missing AVPs
  Don't flag AVP as missing as a consequence of decode error
  Correct inaccurate doc
  Truncate potentially large terms passed to diameter_lib:log/4

4 files changed, 30 insertions, 14 deletions

diff --git a/lib/diameter/doc/src/diameter.xml b/lib/diameter/doc/src/diameter.xml
index ea175a58b8..cb628f9529 100644
--- a/lib/diameter/doc/src/diameter.xml
+++ b/lib/diameter/doc/src/diameter.xml
@@ -1231,9 +1231,7 @@ is not the length of the message in question, as received over the
 transport interface documented in &man_transport;.</p>
 
 <p>
-If <c>exit</c> then a warning report is emitted and the parent of the
-transport process in question exits, which causes the transport
-process itself to exit as described in &man_transport;.
+If <c>exit</c> then the transport process in question exits.
 If <c>handle</c> then the message is processed as usual, a resulting
 &app_handle_request; or &app_handle_answer; callback (if one takes
 place) indicating the <c>5015</c> error (DIAMETER_INVALID_MESSAGE_LENGTH).
diff --git a/lib/diameter/include/diameter_gen.hrl b/lib/diameter/include/diameter_gen.hrl
index e8ffe7f92c..79b8e6ecde 100644
--- a/lib/diameter/include/diameter_gen.hrl
+++ b/lib/diameter/include/diameter_gen.hrl
@@ -185,9 +185,10 @@ decode_avps(Name, Recs) ->
         = lists:foldl(fun(T,A) -> decode(Name, T, A) end,
                       {[], {newrec(Name), []}},
                       Recs),
-    {Rec, Avps, Failed ++ missing(Rec, Name)}.
-%% Append 5005 errors so that a 5014 for the same AVP will take
-%% precedence in a Result-Code/Failed-AVP setting.
+    {Rec, Avps, Failed ++ missing(Rec, Name, Failed)}.
+%% Append 5005 errors so that errors are reported in the order
+%% encountered. Failed-AVP should typically contain the first
+%% encountered error accordg to the RFC.
 
 newrec(Name) ->
     '#new-'(name2rec(Name)).
@@ -200,12 +201,19 @@ newrec(Name) ->
 %%      Failed-AVP AVP SHOULD be included in the message.  The Failed-AVP
 %%      AVP MUST contain an example of the missing AVP complete with the
 %%      Vendor-Id if applicable.  The value field of the missing AVP
-%%      should be of correct minimum length and contain zeroes.
-
-missing(Rec, Name) ->
-    [{5005, empty_avp(F)} || F <- '#info-'(element(1, Rec), fields),
-                             A <- [avp_arity(Name, F)],
-                             false <- [have_arity(A, '#get-'(F, Rec))]].
+%%      should be of correct minimum length and contain zeros.
+
+missing(Rec, Name, Failed) ->
+    Avps = lists:foldl(fun({_, #diameter_avp{code = C, vendor_id = V}}, A) ->
+                               sets:add_element({C,V}, A)
+                       end,
+                       sets:new(),
+                       Failed),
+    [{5005, A} || F <- '#info-'(element(1, Rec), fields),
+                  not have_arity(avp_arity(Name, F), '#get-'(F, Rec)),
+                  #diameter_avp{code = C, vendor_id = V}
+                      = A <- [empty_avp(F)],
+                  not sets:is_element({C,V}, Avps)].
 
 %% Maximum arities have already been checked in building the record.
 
diff --git a/lib/diameter/src/base/diameter_peer_fsm.erl b/lib/diameter/src/base/diameter_peer_fsm.erl
index 2255d0a76b..a9ee4940a3 100644
--- a/lib/diameter/src/base/diameter_peer_fsm.erl
+++ b/lib/diameter/src/base/diameter_peer_fsm.erl
@@ -319,7 +319,7 @@ handle_info(T, #state{} = State) ->
             ?LOG(stop, Reason),
             {stop, {shutdown, Reason}, State};
         stop ->
-            ?LOG(stop, T),
+            ?LOG(stop, truncate(T)),
             {stop, {shutdown, T}, State}
     catch
         exit: {diameter_codec, encode, T} = Reason ->
@@ -355,6 +355,11 @@ code_change(_, State, _) ->
 %% ---------------------------------------------------------------------------
 %% ---------------------------------------------------------------------------
 
+truncate({'DOWN' = T, _, process, Pid, _}) ->
+    {T, Pid};
+truncate(T) ->
+    T.
+
 putr(Key, Val) ->
     put({?MODULE, Key}, Val).
 
diff --git a/lib/diameter/src/base/diameter_watchdog.erl b/lib/diameter/src/base/diameter_watchdog.erl
index de9c4bca33..55c303dec2 100644
--- a/lib/diameter/src/base/diameter_watchdog.erl
+++ b/lib/diameter/src/base/diameter_watchdog.erl
@@ -245,11 +245,16 @@ handle_info(T, #watchdog{} = State) ->
             event(T, State, S),  %%   before 'watchdog'
             {noreply, S};
         stop ->
-            ?LOG(stop, T),
+            ?LOG(stop, truncate(T)),
             event(T, State, State#watchdog{status = down}),
             {stop, {shutdown, T}, State}
     end.
 
+truncate({'DOWN' = T, _, process, Pid, _}) ->
+    {T, Pid};
+truncate(T) ->
+    T.
+
 close({'DOWN', _, process, TPid, {shutdown, Reason}},
       #watchdog{transport = TPid,
                 parent = Pid}) ->