Optimize query string parsing

*  Parsing code was moved to cowlib: cowboy_qs:parse_qs/1
 *  A function was added to build query strings: cowboy_qs:qs/1
 *  Also added cowboy_qs:urlencode/1 and cowboy_qsurldecode/1

Makefile

@@ -11,7 +11,7 @@ PLT_APPS = crypto public_key ssl
 # Dependencies.
 
 DEPS = cowlib ranch
-dep_cowlib = pkg://cowlib 0.3.0
+dep_cowlib = pkg://cowlib 0.4.0
 dep_ranch = pkg://ranch 0.8.5
 
 TEST_DEPS = ct_helper gun

rebar.config

@@ -1,4 +1,4 @@
 {deps, [
-	{cowlib, ".*", {git, "git://github.com/extend/cowlib.git", "0.3.0"}},
+	{cowlib, ".*", {git, "git://github.com/extend/cowlib.git", "0.4.0"}},
 	{ranch, ".*", {git, "git://github.com/extend/ranch.git", "0.8.5"}}
 ]}.

src/cowboy_http.erl

@@ -49,7 +49,6 @@
 -export([urldecode/2]).
 -export([urlencode/1]).
 -export([urlencode/2]).
--export([x_www_form_urlencoded/1]).
 
 %% Parsing.
 
@@ -1037,16 +1036,6 @@ tohexu(C) when C < 17 -> $A + C - 10.
 tohexl(C) when C < 10 -> $0 + C;
 tohexl(C) when C < 17 -> $a + C - 10.
 
--spec x_www_form_urlencoded(binary()) -> list({binary(), binary() | true}).
-x_www_form_urlencoded(<<>>) ->
-	[];
-x_www_form_urlencoded(Qs) ->
-	Tokens = binary:split(Qs, <<"&">>, [global, trim]),
-	[case binary:split(Token, <<"=">>) of
-		[Token] -> {urldecode(Token), true};
-		[Name, Value] -> {urldecode(Name), urldecode(Value)}
-	end || Token <- Tokens].
-
 %% Tests.
 
 -ifdef(TEST).
@@ -1227,20 +1216,6 @@ digits_test_() ->
 	],
 	[{V, fun() -> R = digits(V) end} || {V, R} <- Tests].
 
-x_www_form_urlencoded_test_() ->
-	%% {Qs, Result}
-	Tests = [
-		{<<"">>, []},
-		{<<"a=b">>, [{<<"a">>, <<"b">>}]},
-		{<<"aaa=bbb">>, [{<<"aaa">>, <<"bbb">>}]},
-		{<<"a&b">>, [{<<"a">>, true}, {<<"b">>, true}]},
-		{<<"a=b&c&d=e">>, [{<<"a">>, <<"b">>},
-			{<<"c">>, true}, {<<"d">>, <<"e">>}]},
-		{<<"a=b=c=d=e&f=g">>, [{<<"a">>, <<"b=c=d=e">>}, {<<"f">>, <<"g">>}]},
-		{<<"a+b=c+d">>, [{<<"a b">>, <<"c d">>}]}
-	],
-	[{Qs, fun() -> R = x_www_form_urlencoded(Qs) end} || {Qs, R} <- Tests].
-
 urldecode_test_() ->
 	F = fun(Qs, O) ->
 		try urldecode(Qs, O) of

src/cowboy_req.erl

@@ -279,7 +279,7 @@ qs_val(Name, Req) when is_binary(Name) ->
 	-> {binary() | true | Default, Req} when Req::req(), Default::any().
 qs_val(Name, Req=#http_req{qs=RawQs, qs_vals=undefined}, Default)
 		when is_binary(Name) ->
-	QsVals = cowboy_http:x_www_form_urlencoded(RawQs),
+	QsVals = cow_qs:parse_qs(RawQs),
 	qs_val(Name, Req#http_req{qs_vals=QsVals}, Default);
 qs_val(Name, Req, Default) ->
 	case lists:keyfind(Name, 1, Req#http_req.qs_vals) of
@@ -290,7 +290,7 @@ qs_val(Name, Req, Default) ->
 %% @doc Return the full list of query string values.
 -spec qs_vals(Req) -> {list({binary(), binary() | true}), Req} when Req::req().
 qs_vals(Req=#http_req{qs=RawQs, qs_vals=undefined}) ->
-	QsVals = cowboy_http:x_www_form_urlencoded(RawQs),
+	QsVals = cow_qs:parse_qs(RawQs),
 	qs_vals(Req#http_req{qs_vals=QsVals});
 qs_vals(Req=#http_req{qs_vals=QsVals}) ->
 	{QsVals, Req}.
@@ -776,7 +776,7 @@ body_qs(Req) ->
 body_qs(MaxBodyLength, Req) ->
 	case body(MaxBodyLength, Req) of
 		{ok, Body, Req2} ->
-			{ok, cowboy_http:x_www_form_urlencoded(Body), Req2};
+			{ok, cow_qs:parse_qs(Body), Req2};
 		{error, Reason} ->
 			{error, Reason}
 	end.