Don't use decode_packet/3 for parsing the request-line

First step in making all methods and header names binaries to
get rid of many inconsistencies caused by decode_packet/3.

Methods are all binary now. Note that since they are case
sensitive, the usual methods become <<"GET">>, <<"POST">> and so on.

1 files changed, 41 insertions, 3 deletions

diff --git a/src/cowboy_http.erl b/src/cowboy_http.erl
index f3457dc..83a67fe 100644
--- a/src/cowboy_http.erl
+++ b/src/cowboy_http.erl
@@ -17,6 +17,7 @@
 -module(cowboy_http).
 
 %% Parsing.
+-export([request_line/1]).
 -export([list/2]).
 -export([nonempty_list/2]).
 -export([content_type/1]).
@@ -50,8 +51,6 @@
 -export([urlencode/2]).
 -export([x_www_form_urlencoded/2]).
 
--type method() :: 'OPTIONS' | 'GET' | 'HEAD'
-	| 'POST' | 'PUT' | 'DELETE' | 'TRACE' | binary().
 -type uri() :: '*' | {absoluteURI, http | https, Host::binary(),
 	Port::integer() | undefined, Path::binary()}
 	| {scheme, Scheme::binary(), binary()}
@@ -73,7 +72,6 @@
 -type headers() :: [{header(), iodata()}].
 -type status() :: non_neg_integer() | binary().
 
--export_type([method/0]).
 -export_type([uri/0]).
 -export_type([version/0]).
 -export_type([header/0]).
@@ -86,6 +84,46 @@
 
 %% Parsing.
 
+%% @doc Parse a request-line.
+-spec request_line(binary())
+	-> {binary(), binary(), version()} | {error, badarg}.
+request_line(Data) ->
+	token(Data,
+		fun (Rest, Method) ->
+			whitespace(Rest,
+				fun (Rest2) ->
+					uri_to_abspath(Rest2,
+						fun (Rest3, AbsPath) ->
+							whitespace(Rest3,
+								fun (<< "HTTP/", Maj, ".", Min, _/binary >>)
+											when Maj >= $0, Maj =< $9,
+												Min >= $0, Min =< $9 ->
+										{Method, AbsPath, {Maj - $0, Min - $0}};
+									(_) ->
+										{error, badarg}
+								end)
+						end)
+				end)
+		end).
+
+%% We just want to extract the path/qs and skip everything else.
+%% We do not really parse the URI, nor do we need to.
+uri_to_abspath(Data, Fun) ->
+	case binary:split(Data, <<" ">>) of
+		[_] -> %% We require the HTTP version.
+			{error, badarg};
+		[URI, Rest] ->
+			case binary:split(URI, <<"://">>) of
+				[_] -> %% Already is a path or "*".
+					Fun(Rest, URI);
+				[_, NoScheme] ->
+					case binary:split(NoScheme, <<"/">>) of
+						[_] -> <<"/">>;
+						[_, NoHost] -> Fun(Rest, << "/", NoHost/binary >>)
+					end
+			end
+	end.
+
 %% @doc Parse a non-empty list of the given type.
 -spec nonempty_list(binary(), fun()) -> [any(), ...] | {error, badarg}.
 nonempty_list(Data, Fun) ->