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diff --git a/src/cowboy_dispatcher.erl b/src/cowboy_dispatcher.erl
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+%% Copyright (c) 2011, Loïc Hoguin <[email protected]>
+%%
+%% Permission to use, copy, modify, and/or distribute this software for any
+%% purpose with or without fee is hereby granted, provided that the above
+%% copyright notice and this permission notice appear in all copies.
+%%
+%% THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+%% WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+%% MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+%% ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+%% WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+%% ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+%% OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+
+-module(cowboy_dispatcher).
+-export([split_host/1, split_path/1, match/3]). %% API.
+
+-include("include/types.hrl").
+-include_lib("eunit/include/eunit.hrl").
+
+%% API.
+
+-spec split_host(Host::string()) -> Tokens::path_tokens().
+split_host(Host) ->
+	string:tokens(Host, ".").
+
+-spec split_path(Path::string()) -> {Tokens::path_tokens(), Qs::string()}.
+split_path(Path) ->
+	case string:chr(Path, $?) of
+		0 ->
+			{string:tokens(Path, "/"), []};
+		N ->
+			{Path2, [$?|Qs]} = lists:split(N - 1, Path),
+			{string:tokens(Path2, "/"), Qs}
+	end.
+
+-spec match(Host::path_tokens(), Path::path_tokens(), Dispatch::dispatch())
+	-> {ok, Handler::module(), Opts::term(), Binds::bindings()} | {error, notfound}.
+match(_Host, _Path, []) ->
+	{error, notfound};
+match(_Host, _Path, [{'_', '_', Handler, Opts}|_Tail]) ->
+	{ok, Handler, Opts, []};
+match(Host, Path, [{HostMatch, PathMatch, Handler, Opts}|Tail]) ->
+	case try_match(host, Host, HostMatch) of
+		false -> match(Host, Path, Tail);
+		{true, HostBinds} -> case try_match(path, Path, PathMatch) of
+			false -> match(Host, Path, Tail);
+			{true, PathBinds} -> {ok, Handler, Opts, HostBinds ++ PathBinds}
+		end
+	end.
+
+%% Internal.
+
+-spec try_match(Type::host | path, List::path_tokens(), Match::match())
+	-> {true, Binds::bindings()} | false.
+try_match(_Type, _List, '_') ->
+	{true, []};
+try_match(_Type, List, Match) when length(List) =/= length(Match) ->
+	false;
+try_match(host, List, Match) ->
+	list_match(lists:reverse(List), lists:reverse(Match), []);
+try_match(path, List, Match) ->
+	list_match(List, Match, []).
+
+-spec list_match(List::path_tokens(), Match::match(), Binds::bindings())
+	-> {true, Binds::bindings()} | false.
+%% Atom '_' matches anything, continue.
+list_match([_E|Tail], ['_'|TailMatch], Binds) ->
+	list_match(Tail, TailMatch, Binds);
+%% Both values match, continue.
+list_match([E|Tail], [E|TailMatch], Binds) ->
+	list_match(Tail, TailMatch, Binds);
+%% Bind E to the variable name V and continue.
+list_match([E|Tail], [V|TailMatch], Binds) when is_atom(V) ->
+	list_match(Tail, TailMatch, [{V, E}|Binds]);
+%% Values don't match, stop.
+list_match([_E|_Tail], [_F|_TailMatch], _Binds) ->
+	false;
+%% Match complete.
+list_match([], [], Binds) ->
+	{true, Binds}.
+
+%% Tests.
+
+-ifdef(TEST).
+
+split_host_test_() ->
+	%% {Host, Result}
+	Tests = [
+		{"", []},
+		{".........", []},
+		{"*", ["*"]},
+		{"cowboy.dev-extend.eu", ["cowboy", "dev-extend", "eu"]},
+		{"dev-extend..eu", ["dev-extend", "eu"]},
+		{"dev-extend.eu", ["dev-extend", "eu"]},
+		{"a.b.c.d.e.f.g.h.i.j.k.l.m.n.o.p.q.r.s.t.u.v.w.x.y.z",
+			["a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k", "l", "m",
+			 "n", "o", "p", "q", "r", "s", "t", "u", "v", "w", "x", "y", "z"]}
+	],
+	[{H, fun() -> R = split_host(H) end} || {H, R} <- Tests].
+
+split_path_test_() ->
+	%% {Path, Result, QueryString}
+	Tests = [
+		{"?", [], []},
+		{"???", [], "??"},
+		{"*", ["*"], []},
+		{"/", [], []},
+		{"/users", ["users"], []},
+		{"/users?", ["users"], []},
+		{"/users?a", ["users"], "a"},
+		{"/users/42/friends?a=b&c=d&e=notsure?whatever",
+			["users", "42", "friends"], "a=b&c=d&e=notsure?whatever"}
+	],
+	[{P, fun() -> {R, Qs} = split_path(P) end} || {P, R, Qs} <- Tests].
+
+match_test_() ->
+	Dispatch = [
+		{["www", '_', "dev-extend", "eu"], ["users", '_', "mails"],
+			match_any_subdomain_users, []},
+		{["dev-extend", "eu"], ["users", id, "friends"],
+			match_extend_users_friends, []},
+		{["dev-extend", var], ["threads", var],
+			match_duplicate_vars, [we, {expect, two}, var, here]},
+		{["dev-extend", "eu"], '_', match_extend, []},
+		{["erlang", ext], '_', match_erlang_ext, []},
+		{'_', ["users", id, "friends"], match_users_friends, []},
+		{'_', '_', match_any, []}
+	],
+	%% {Host, Path, Result}
+	Tests = [
+		{["any"], [], {ok, match_any, [], []}},
+		{["www", "any", "dev-extend", "eu"], ["users", "42", "mails"],
+			{ok, match_any_subdomain_users, [], []}},
+		{["www", "dev-extend", "eu"], ["users", "42", "mails"],
+			{ok, match_any, [], []}},
+		{["www", "any", "dev-extend", "eu"], ["not_users", "42", "mails"],
+			{ok, match_any, [], []}},
+		{["dev-extend", "eu"], [], {ok, match_extend, [], []}},
+		{["dev-extend", "eu"], ["users", "42", "friends"],
+			{ok, match_extend_users_friends, [], [{id, "42"}]}},
+		{["erlang", "fr"], '_', {ok, match_erlang_ext, [], [{ext, "fr"}]}},
+		{["any"], ["users", "444", "friends"],
+			{ok, match_users_friends, [], [{id, "444"}]}},
+		{["dev-extend", "eu"], ["threads", "987"],
+			{ok, match_duplicate_vars, [we, {expect, two}, var, here],
+			[{var, "eu"}, {var, "987"}]}}
+	],
+	[{lists:flatten(io_lib:format("~p, ~p", [H, P])), fun() ->
+		R = match(H, P, Dispatch)
+	end} || {H, P, R} <- Tests].
+
+-endif.