decode frames

apps/sdlan/src/quic/quic_client.erl

@@ -19,8 +19,27 @@ start() ->
 do_start() ->
     Port = 1365,
     {ok, Conn} = quicer:connect("localhost", Port, [{alpn, ["punchnet/1.0"]}, {verify, none}], 5000),
+
+    receive
+        {quic, connected, Conn} ->
+            ok
+    after 1000 ->
+        ok
+    end,
+
     {ok, Stm} = quicer:start_stream(Conn, []),
-    {ok, 4} = quicer:send(Stm, <<"ping">>),
-    logger:debug("[quic_client] client send success"),
+    receive
+        {quic, stream_started, Stm} ->
+            ok
+    after 1000 ->
+        ok
+    end,
+
+    Data = <<"ping">>,
+    Len = byte_size(Data),
+    Payload = <<Len:16, Data/binary, Len:16, Data/binary>>,
+
+    {ok, SendLen} = quicer:send(Stm, Payload),
+    logger:debug("[quic_client] client send success: ~p", [SendLen]),
     receive {quic, <<"pong">>, Stm, _Props} -> ok end,
     ok = quicer:close_connection(Conn).

apps/sdlan/src/quic/sdlan_quic_channel.erl

@@ -11,6 +11,8 @@
 
 -behaviour(gen_statem).
 
+-define(MAX_FRAME_LEN, 16384).
+
 %% API
 -export([start_link/1]).
 
@@ -19,7 +21,9 @@
 
 -record(state, {
     conn :: quicer:connection_handle(),
-    stream_handle :: undefined | quicer:stream_handle()
+    stream_handle :: undefined | quicer:stream_handle(),
+    %% 累积器，用于处理协议framing的解析
+    buf = <<>>
 }).
 
 %%%===================================================================
@@ -65,11 +69,21 @@ handle_event(internal, do_init, initializing, State = #state{conn = Conn}) ->
             {stop, Reason, State}
     end;
 
-%% 处理quicer相关的信息
-handle_event(info, {quic, Msg, Stream, _Props}, _StateName, State = #state{stream_handle = Stream}) ->
-    logger:debug("[sdlan_quic_channel] get message: ~p", [Msg]),
+handle_event(info, {frame, Frame}, _StateName, State = #state{}) ->
+    logger:debug("[sdlan_quic_channel] get frame: ~p", [Frame]),
     {keep_state, State};
 
+%% 处理quicer相关的信息
+handle_event(info, {quic, Data, Stream, _Props}, _StateName, State = #state{stream_handle = Stream, buf = Buf}) ->
+    logger:debug("[sdlan_quic_channel] get message: ~p", [Data]),
+    case decode_frames(<<Buf/binary, Data/binary>>) of
+        {error, Reason} ->
+            {stop, Reason, State};
+        {ok, NBuf, Frames} ->
+            Actions = [{next_event, info, {frame, Frame}} || Frame <- Frames],
+            {keep_state, State#state{buf = NBuf}, Actions}
+    end;
+
 handle_event(info, {quic_closed, Stream, _Props}, _StateName, State = #state{conn = Conn, stream_handle = Stream}) ->
     quicer:close_connection(Conn),
     {stop, connection_closed, State};
@@ -106,3 +120,16 @@ code_change(_OldVsn, StateName, State = #state{}, _Extra) ->
 %%%===================================================================
 %%% Internal functions
 %%%===================================================================
+
+%% 有2种情况
+%% 1. 收到了多个完整的请求
+%% 2. 不完整，则不处理
+-spec decode_frames(Buf :: binary()) -> {ok, RestBin::binary(), Frames :: list()} | {error, Reason :: any()}.
+decode_frames(Buf) when is_binary(Buf) ->
+    decode_frames0(Buf, []).
+decode_frames0(<<Len:16, _/binary>>, _Frames) when Len > ?MAX_FRAME_LEN ->
+    {error, frame_too_large};
+decode_frames0(<<Len:16, Frame:Len/binary, Rest/binary>>, Frames) ->
+    decode_frames0(Rest, [Frame|Frames]);
+decode_frames0(Rest, Frames) ->
+    {ok, Rest, lists:reverse(Frames)}.