Add +warn_missing_spec and fix specs

Makefile

@@ -4,6 +4,8 @@ PROJECT = cowboy
 
 # Options.
 
+ERLC_OPTS ?= -Werror +debug_info +warn_export_all +warn_export_vars \
+	+warn_shadow_vars +warn_obsolete_guard +warn_missing_spec
 COMPILE_FIRST = cowboy_middleware cowboy_sub_protocol
 CT_SUITES = eunit http spdy ws
 PLT_APPS = crypto public_key ssl

src/cowboy_app.erl

@@ -18,8 +18,10 @@
 -export([start/2]).
 -export([stop/1]).
 
-start(_Type, _Args) ->
+-spec start(_, _) -> {ok, pid()}.
+start(_, _) ->
 	cowboy_sup:start_link().
 
-stop(_State) ->
+-spec stop(_) -> ok.
+stop(_) ->
 	ok.

src/cowboy_clock.erl

@@ -59,6 +59,7 @@ rfc1123(DateTime) ->
 
 %% gen_server.
 
+-spec init([]) -> {ok, #state{}}.
 init([]) ->
 	?MODULE = ets:new(?MODULE, [set, protected,
 		named_table, {read_concurrency, true}]),
@@ -68,15 +69,20 @@ init([]) ->
 	ets:insert(?MODULE, {rfc1123, B}),
 	{ok, #state{universaltime=T, rfc1123=B, tref=TRef}}.
 
+-spec handle_call(any(), _, State)
+	-> {reply, ignored, State} | {stop, normal, stopped, State}
+	when State::#state{}.
 handle_call(stop, _From, State=#state{tref=TRef}) ->
 	{ok, cancel} = timer:cancel(TRef),
 	{stop, normal, stopped, State};
 handle_call(_Request, _From, State) ->
 	{reply, ignored, State}.
 
+-spec handle_cast(_, State) -> {noreply, State} when State::#state{}.
 handle_cast(_Msg, State) ->
 	{noreply, State}.
 
+-spec handle_info(any(), State) -> {noreply, State} when State::#state{}.
 handle_info(update, #state{universaltime=Prev, rfc1123=B1, tref=TRef}) ->
 	T = erlang:universaltime(),
 	B2 = update_rfc1123(B1, Prev, T),
@@ -85,9 +91,11 @@ handle_info(update, #state{universaltime=Prev, rfc1123=B1, tref=TRef}) ->
 handle_info(_Info, State) ->
 	{noreply, State}.
 
+-spec terminate(_, _) -> ok.
 terminate(_Reason, _State) ->
 	ok.
 
+-spec code_change(_, State, _) -> {ok, State} when State::#state{}.
 code_change(_OldVsn, State, _Extra) ->
 	{ok, State}.
 

src/cowboy_spdy.erl

@@ -37,8 +37,11 @@
 -export([send/2]).
 -export([sendfile/2]).
 
+-type streamid() :: non_neg_integer().
+-type socket() :: {pid(), streamid()}.
+
 -record(child, {
-	streamid :: non_neg_integer(),
+	streamid :: streamid(),
 	pid :: pid(),
 	input = nofin :: fin | nofin,
 	in_buffer = <<>> :: binary(),
@@ -59,7 +62,7 @@
 	peer,
 	zdef,
 	zinf,
-	last_streamid = 0 :: non_neg_integer(),
+	last_streamid = 0 :: streamid(),
 	children = [] :: [#child{}]
 }).
 
@@ -202,6 +205,7 @@ loop(State=#state{parent=Parent, socket=Socket, transport=Transport,
 		terminate(State)
 	end.
 
+-spec system_continue(_, _, #state{}) -> ok.
 system_continue(_, _, State) ->
 	loop(State).
 
@@ -209,6 +213,7 @@ system_continue(_, _, State) ->
 system_terminate(Reason, _, _, _) ->
 	exit(Reason).
 
+-spec system_code_change(Misc, _, _, _) -> {ok, Misc} when Misc::#state{}.
 system_code_change(Misc, _, _, _) ->
 	{ok, Misc}.
 
@@ -351,6 +356,11 @@ delete_child(Pid, State=#state{children=Children}) ->
 
 %% Request process.
 
+-spec request_init(socket(), {inet:ip_address(), inet:port_number()},
+		cowboy:onrequest_fun(), cowboy:onresponse_fun(),
+		cowboy_middleware:env(), [module()],
+		binary(), binary(), binary(), binary(), [{binary(), binary()}])
+	-> ok.
 request_init(FakeSocket, Peer, OnRequest, OnResponse,
 		Env, Middlewares, Method, Host, Path, Version, Headers) ->
 	{Host2, Port} = cow_http:parse_fullhost(Host),
@@ -404,6 +414,7 @@ resume(Env, Tail, Module, Function, Args) ->
 
 %% Reply functions used by cowboy_req.
 
+-spec reply(socket(), binary(), cowboy:http_headers(), iodata()) -> ok.
 reply(Socket = {Pid, _}, Status, Headers, Body) ->
 	_ = case iolist_size(Body) of
 		0 -> Pid ! {reply, Socket, Status, Headers};
@@ -411,23 +422,29 @@ reply(Socket = {Pid, _}, Status, Headers, Body) ->
 	end,
 	ok.
 
+-spec stream_reply(socket(), binary(), cowboy:http_headers()) -> ok.
 stream_reply(Socket = {Pid, _}, Status, Headers) ->
 	_ = Pid ! {stream_reply, Socket, Status, Headers},
 	ok.
 
+-spec stream_data(socket(), iodata()) -> ok.
 stream_data(Socket = {Pid, _}, Data) ->
 	_ = Pid ! {stream_data, Socket, Data},
 	ok.
 
+-spec stream_close(socket()) -> ok.
 stream_close(Socket = {Pid, _}) ->
 	_ = Pid ! {stream_close, Socket},
 	ok.
 
 %% Internal transport functions.
 
+-spec name() -> spdy.
 name() ->
 	spdy.
 
+-spec recv(socket(), non_neg_integer(), timeout())
+	-> {ok, binary()} | {error, timeout}.
 recv(Socket = {Pid, _}, Length, Timeout) ->
 	_ = Pid ! {recv, Socket, self(), Length, Timeout},
 	receive
@@ -435,12 +452,14 @@ recv(Socket = {Pid, _}, Length, Timeout) ->
 			Ret
 	end.
 
+-spec send(socket(), iodata()) -> ok.
 send(Socket, Data) ->
 	stream_data(Socket, Data).
 
 %% We don't wait for the result of the actual sendfile call,
 %% therefore we can't know how much was actually sent.
 %% This isn't a problem as we don't use this value in Cowboy.
+-spec sendfile(socket(), file:name_all()) -> {ok, undefined}.
 sendfile(Socket = {Pid, _}, Filepath) ->
 	_ = Pid ! {sendfile, Socket, Filepath},
 	{ok, undefined}.

src/cowboy_static.erl

@@ -39,6 +39,7 @@
 
 -type state() :: {binary(), {ok, #file_info{}} | {error, atom()}, extra()}.
 
+-spec init(_, _, _) -> {upgrade, protocol, cowboy_rest}.
 init(_, _, _) ->
 	{upgrade, protocol, cowboy_rest}.
 

src/cowboy_sup.erl

@@ -22,6 +22,8 @@
 start_link() ->
 	supervisor:start_link({local, ?MODULE}, ?MODULE, []).
 
+-spec init([])
+	-> {ok, {{supervisor:strategy(), 10, 10}, [supervisor:child_spec()]}}.
 init([]) ->
 	Procs = [{cowboy_clock, {cowboy_clock, start_link, []},
 		permanent, 5000, worker, [cowboy_clock]}],