Merge branch 'peterdmv/inets/fix_http_client/OTP-15242' into maint-20

* peterdmv/inets/fix_http_client/OTP-15242:
  inets: Prepare for release
  inets: Robust handling of 204, 304, 1xx responses

Change-Id: I12dced982907c3462fefb8a4ffaae8b365821f97

3 files changed, 70 insertions, 6 deletions

diff --git a/lib/inets/src/http_client/httpc_handler.erl b/lib/inets/src/http_client/httpc_handler.erl
index 26e4f4e699..1a2ce277bf 100644
--- a/lib/inets/src/http_client/httpc_handler.erl
+++ b/lib/inets/src/http_client/httpc_handler.erl
@@ -980,13 +980,23 @@ handle_http_body(_, #state{status = {ssl_tunnel, Request},
     NewState     = answer_request(Request, ClientErrMsg, State),
     {stop, normal, NewState};
 
-handle_http_body(<<>>, #state{status_line = {_,304, _}} = State) ->
+%% All 1xx (informational), 204 (no content), and 304 (not modified)
+%% responses MUST NOT include a message-body, and thus are always
+%% terminated by the first empty line after the header fields.
+%% This implies that chunked encoding MUST NOT be used for these
+%% status codes.
+handle_http_body(<<>>, #state{headers = Headers,
+                              status_line = {_,StatusCode, _}} = State)
+  when Headers#http_response_h.'transfer-encoding' =/= "chunked" andalso
+       (StatusCode =:= 204 orelse                       %% No Content
+        StatusCode =:= 304 orelse                       %% Not Modified
+        100 =< StatusCode andalso StatusCode =< 199) -> %% Informational
     handle_response(State#state{body = <<>>});
 
-handle_http_body(<<>>, #state{status_line = {_,204, _}} = State) ->
-    handle_response(State#state{body = <<>>});
 
-handle_http_body(<<>>, #state{request = #request{method = head}} = State) ->
+handle_http_body(<<>>, #state{headers = Headers,
+                              request = #request{method = head}} = State)
+  when Headers#http_response_h.'transfer-encoding' =/= "chunked" ->
     handle_response(State#state{body = <<>>});
 
 handle_http_body(Body, #state{headers       = Headers, 
diff --git a/lib/inets/test/httpc_SUITE.erl b/lib/inets/test/httpc_SUITE.erl
index d723fd0460..f3898e1b74 100644
--- a/lib/inets/test/httpc_SUITE.erl
+++ b/lib/inets/test/httpc_SUITE.erl
@@ -157,7 +157,8 @@ misc() ->
     [
      server_does_not_exist,
      timeout_memory_leak,
-     wait_for_whole_response
+     wait_for_whole_response,
+     post_204_chunked
     ].
 
 %%--------------------------------------------------------------------
@@ -1243,6 +1244,59 @@ wait_for_whole_response(Config) when is_list(Config) ->
      ReqSeqNumServer ! shutdown.
 
 %%--------------------------------------------------------------------
+post_204_chunked() ->
+    [{doc,"Test that chunked encoded 204 responses do not freeze the http client"}].
+post_204_chunked(_Config) ->
+    Msg = "HTTP/1.1 204 No Content\r\n" ++
+        "Date: Thu, 23 Aug 2018 13:36:29 GMT\r\n" ++
+        "Content-Type: text/html\r\n" ++
+        "Server: inets/6.5.2.3\r\n" ++
+        "Cache-Control: no-cache\r\n" ++
+        "Pragma: no-cache\r\n" ++
+        "Expires: Fri, 24 Aug 2018 07:49:35 GMT\r\n" ++
+        "Transfer-Encoding: chunked\r\n" ++
+        "\r\n",
+    Chunk = "0\r\n\r\n",
+
+    {ok, ListenSocket} = gen_tcp:listen(0, [{active,once}, binary]),
+    {ok,{_,Port}} = inet:sockname(ListenSocket),
+    spawn(fun () -> custom_server(Msg, Chunk, ListenSocket) end),
+
+    {ok,Host} = inet:gethostname(),
+    End = "/cgi-bin/erl/httpd_example:post_204",
+    URL = ?URL_START ++ Host ++ ":" ++ integer_to_list(Port) ++ End,
+    {ok, _} = httpc:request(post, {URL, [], "text/html", []}, [], []),
+    timer:sleep(500),
+    %% Second request times out in the faulty case.
+    {ok, _} = httpc:request(post, {URL, [], "text/html", []}, [], []).
+
+custom_server(Msg, Chunk, ListenSocket) ->
+    {ok, Accept} = gen_tcp:accept(ListenSocket),
+    receive_packet(),
+    send_response(Msg, Chunk, Accept),
+    custom_server_loop(Msg, Chunk, Accept).
+
+custom_server_loop(Msg, Chunk, Accept) ->
+    receive_packet(),
+    send_response(Msg, Chunk, Accept),
+    custom_server_loop(Msg, Chunk, Accept).
+
+send_response(Msg, Chunk, Socket) ->
+    inet:setopts(Socket, [{active, once}]),
+    gen_tcp:send(Socket, Msg),
+    timer:sleep(250),
+    gen_tcp:send(Socket, Chunk).
+
+receive_packet() ->
+    receive
+        {tcp, _, Msg} ->
+            ct:log("Message received: ~p", [Msg])
+    after
+        1000 ->
+            ct:fail("Timeout: did not recive packet")
+    end.
+
+%%--------------------------------------------------------------------
 stream_fun_server_close() ->
     [{doc, "Test that an error msg is received when using a receiver fun as stream target"}].
 stream_fun_server_close(Config) when is_list(Config) ->
diff --git a/lib/inets/vsn.mk b/lib/inets/vsn.mk
index c1f5a2c4e0..3259a8a195 100644
--- a/lib/inets/vsn.mk
+++ b/lib/inets/vsn.mk
@@ -19,6 +19,6 @@
 # %CopyrightEnd%
 
 APPLICATION = inets
-INETS_VSN   = 6.5.2.3
+INETS_VSN   = 6.5.2.4
 PRE_VSN     =
 APP_VSN     = "$(APPLICATION)-$(INETS_VSN)$(PRE_VSN)"