1 // Copyright 2016 The Chromium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4 
5 #ifndef QUICHE_HTTP2_DECODER_PAYLOAD_DECODERS_GOAWAY_PAYLOAD_DECODER_H_
6 #define QUICHE_HTTP2_DECODER_PAYLOAD_DECODERS_GOAWAY_PAYLOAD_DECODER_H_
7 
8 // Decodes the payload of a GOAWAY frame.
9 
10 // TODO(jamessynge): Sweep through all payload decoders, changing the names of
11 // the PayloadState enums so that they are really states, and not actions.
12 
13 #include "quiche/http2/decoder/decode_buffer.h"
14 #include "quiche/http2/decoder/decode_status.h"
15 #include "quiche/http2/decoder/frame_decoder_state.h"
16 #include "quiche/http2/http2_structures.h"
17 #include "quiche/common/platform/api/quiche_export.h"
18 
19 namespace http2 {
20 namespace test {
21 class GoAwayPayloadDecoderPeer;
22 }  // namespace test
23 
24 class QUICHE_EXPORT GoAwayPayloadDecoder {
25  public:
26   // States during decoding of a GOAWAY frame.
27   enum class PayloadState {
28     // At the start of the GOAWAY frame payload, ready to start decoding the
29     // fixed size fields into goaway_fields_.
30     kStartDecodingFixedFields,
31 
32     // Handle the DecodeStatus returned from starting or resuming the
33     // decoding of Http2GoAwayFields into goaway_fields_. If complete,
34     // calls OnGoAwayStart.
35     kHandleFixedFieldsStatus,
36 
37     // Report the Opaque Data portion of the payload to the listener's
38     // OnGoAwayOpaqueData method, and call OnGoAwayEnd when the end of the
39     // payload is reached.
40     kReadOpaqueData,
41 
42     // The fixed size fields weren't all available when the decoder first
43     // tried to decode them (state kStartDecodingFixedFields); this state
44     // resumes the decoding when ResumeDecodingPayload is called later.
45     kResumeDecodingFixedFields,
46   };
47 
48   // Starts the decoding of a GOAWAY frame's payload, and completes it if
49   // the entire payload is in the provided decode buffer.
50   DecodeStatus StartDecodingPayload(FrameDecoderState* state, DecodeBuffer* db);
51 
52   // Resumes decoding a GOAWAY frame's payload that has been split across
53   // decode buffers.
54   DecodeStatus ResumeDecodingPayload(FrameDecoderState* state,
55                                      DecodeBuffer* db);
56 
57  private:
58   friend class test::GoAwayPayloadDecoderPeer;
59 
60   Http2GoAwayFields goaway_fields_;
61   PayloadState payload_state_;
62 };
63 
64 }  // namespace http2
65 
66 #endif  // QUICHE_HTTP2_DECODER_PAYLOAD_DECODERS_GOAWAY_PAYLOAD_DECODER_H_
67