Better handle socket closing with loop handlers

We now read from the socket to be able to detect errors or TCP close
events, and buffer the data if any. Once the data receive goes over
a certain limit, which defaults to 5000 bytes, we simply close the
connection with an {error, overflow} reason.

test/http_SUITE.erl

@@ -49,6 +49,7 @@
 -export([onresponse_crash/1]).
 -export([onresponse_reply/1]).
 -export([pipeline/1]).
+-export([pipeline_long_polling/1]).
 -export([rest_bad_accept/1]).
 -export([rest_created_path/1]).
 -export([rest_expires/1]).
@@ -112,6 +113,7 @@ groups() ->
 		nc_rand,
 		nc_zero,
 		pipeline,
+		pipeline_long_polling,
 		rest_bad_accept,
 		rest_created_path,
 		rest_expires,
@@ -432,6 +434,8 @@ The document has moved
 <A HREF=\"http://www.google.co.il/\">here</A>.
 </BODY></HTML>",
 	Tests = [
+		{102, <<"GET /long_polling HTTP/1.1\r\nHost: localhost\r\n"
+			"Content-Length: 5000\r\n\r\n", 0:5000/unit:8 >>},
 		{200, ["GET / HTTP/1.0\r\nHost: localhost\r\n"
 			"Set-Cookie: ", HugeCookie, "\r\n\r\n"]},
 		{200, "\r\n\r\n\r\n\r\n\r\nGET / HTTP/1.1\r\nHost: localhost\r\n\r\n"},
@@ -449,6 +453,8 @@ The document has moved
 		{408, "GET / HTTP/1.1\r\nHost: localhost\r\n\r"},
 		{414, Huge},
 		{400, "GET / HTTP/1.1\r\n" ++ Huge},
+		{500, <<"GET /long_polling HTTP/1.1\r\nHost: localhost\r\n"
+			"Content-Length: 100000\r\n\r\n", 0:100000/unit:8 >>},
 		{505, "GET / HTTP/1.2\r\nHost: localhost\r\n\r\n"},
 		{closed, ""},
 		{closed, "\r\n"},
@@ -758,6 +764,16 @@ pipeline(Config) ->
 	{ok, 200, _, Client11} = cowboy_client:response(Client10),
 	{error, closed} = cowboy_client:response(Client11).
 
+pipeline_long_polling(Config) ->
+	Client = ?config(client, Config),
+	{ok, Client2} = cowboy_client:request(<<"GET">>,
+		build_url("/long_polling", Config), Client),
+	{ok, Client3} = cowboy_client:request(<<"GET">>,
+		build_url("/long_polling", Config), Client2),
+	{ok, 102, _, Client4} = cowboy_client:response(Client3),
+	{ok, 102, _, Client5} = cowboy_client:response(Client4),
+	{error, closed} = cowboy_client:response(Client5).
+
 rest_bad_accept(Config) ->
 	Client = ?config(client, Config),
 	{ok, Client2} = cowboy_client:request(<<"GET">>,

test/http_handler_long_polling.erl

@@ -19,4 +19,6 @@ info(timeout, Req, State) ->
 	{loop, Req, State - 1, hibernate}.
 
 terminate({normal, shutdown}, _, _) ->
+	ok;
+terminate({error, overflow}, _, _) ->
 	ok.