blob: c56417d4f5a8b708ff76965656b8f4c5d1ba2514 [file] [log] [blame]
// Copyright 2016 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
// Decodes the payload of a HEADERS frame.
#include "http2/decoder/decode_buffer.h"
#include "http2/decoder/decode_status.h"
#include "http2/decoder/frame_decoder_state.h"
#include "http2/http2_structures.h"
#include "common/platform/api/quiche_export.h"
namespace http2 {
namespace test {
class HeadersPayloadDecoderPeer;
} // namespace test
class QUICHE_EXPORT_PRIVATE HeadersPayloadDecoder {
// States during decoding of a HEADERS frame, unless the fast path kicks
// in, in which case the state machine will be bypassed.
enum class PayloadState {
// The PADDED flag is set, and we now need to read the Pad Length field
// (the first byte of the payload, after the common frame header).
// The PRIORITY flag is set, and we now need to read the fixed size priority
// fields (E, Stream Dependency, Weight) into priority_fields_. Calls on
// OnHeadersPriority if completely decodes those fields.
// The decoder passes the non-padding portion of the remaining payload
// (i.e. the HPACK block fragment) to the listener's OnHpackFragment method.
// The decoder has finished with the HPACK block fragment, and is now
// ready to skip the trailing padding, if the frame has any.
// The fixed size fields weren't all available when the decoder first tried
// to decode them (state kStartDecodingPriorityFields); this state resumes
// the decoding when ResumeDecodingPayload is called later.
// Starts the decoding of a HEADERS frame's payload, and completes it if
// the entire payload is in the provided decode buffer.
DecodeStatus StartDecodingPayload(FrameDecoderState* state, DecodeBuffer* db);
// Resumes decoding a HEADERS frame's payload that has been split across
// decode buffers.
DecodeStatus ResumeDecodingPayload(FrameDecoderState* state,
DecodeBuffer* db);
friend class test::HeadersPayloadDecoderPeer;
PayloadState payload_state_;
Http2PriorityFields priority_fields_;
} // namespace http2