Fix stream handler state being discarded on terminate

When we have to send a response before terminating a stream,
we call info. The state returned by this info call was
discarded when we called terminate after that. This commit
fixes it.

There are no tests for this, however the new metrics test
in the next commit requires the correct behavior so this
is ultimately covered.

src/cowboy_http.erl

@@ -932,9 +932,8 @@ stream_reset(State, StreamID, StreamError={internal_error, _, _}) ->
 stream_terminate(State0=#state{socket=Socket, transport=Transport,
 		out_streamid=OutStreamID, out_state=OutState,
 		streams=Streams0, children=Children0}, StreamID, Reason) ->
-	{value, #stream{state=StreamState, version=Version}, Streams}
-		= lists:keytake(StreamID, #stream.id, Streams0),
-	State1 = case OutState of
+	#stream{version=Version} = lists:keyfind(StreamID, #stream.id, Streams0),
+	State1 = #state{streams=Streams1} = case OutState of
 		wait when element(1, Reason) =:= internal_error ->
 			info(State0, StreamID, {response, 500, #{<<"content-length">> => <<"0">>}, <<>>});
 		wait ->
@@ -945,18 +944,20 @@ stream_terminate(State0=#state{socket=Socket, transport=Transport,
 		_ -> %% done or Version =:= 'HTTP/1.0'
 			State0
 	end,
+	%% Remove the stream from the state.
+	{value, #stream{state=StreamState}, Streams}
+		= lists:keytake(StreamID, #stream.id, Streams1),
+	State2 = State1#state{streams=Streams},
+	%% Stop the stream.
+	stream_call_terminate(StreamID, Reason, StreamState),
+	Children = cowboy_children:shutdown(Children0, StreamID),
 	%% We reset the timeout if there are no active streams anymore.
 	State = case Streams of
-		[] -> set_timeout(State1);
-		_ -> State1
+		[] -> set_timeout(State2);
+		_ -> State2
 	end,
-
-	stream_call_terminate(StreamID, Reason, StreamState),
-
-	Children = cowboy_children:shutdown(Children0, StreamID),
-
+	%% Move on to the next stream.
 	%% @todo Skip the body, if any, or drop the connection if too large.
-
 	%% @todo Only do this if Current =:= StreamID.
 	NextOutStreamID = OutStreamID + 1,
 	case lists:keyfind(NextOutStreamID, #stream.id, Streams) of

src/cowboy_http2.erl

@@ -777,8 +777,9 @@ stream_terminate(State=#state{socket=Socket, transport=Transport,
 	case lists:keytake(StreamID, #stream.id, Streams0) of
 		%% When the stream terminates normally (without sending RST_STREAM)
 		%% and no response was sent, we need to send a proper response back to the client.
-		{value, #stream{state=StreamState, local=idle}, Streams} when Reason =:= normal ->
-			State1 = info(State, StreamID, {response, 204, #{}, <<>>}),
+		{value, #stream{local=idle}, Streams} when Reason =:= normal ->
+			State1 = #state{streams=Streams1} = info(State, StreamID, {response, 204, #{}, <<>>}),
+			#stream{state=StreamState} = lists:keyfind(StreamID, #stream.id, Streams1),
 			stream_call_terminate(StreamID, Reason, StreamState),
 			Children = cowboy_children:shutdown(Children0, StreamID),
 			State1#state{streams=Streams, children=Children};