blob: b497fe7a47ca58e18101032294e6d1a2349d359f [file] [log] [blame]
// Copyright 2017 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.
// HpackDecoderAdapter uses http2::HpackDecoder to decode HPACK blocks into
// HTTP/2 header lists as outlined in
#include <stddef.h>
#include <cstdint>
#include <memory>
#include "base/macros.h"
#include "net/third_party/quiche/src/http2/hpack/decoder/hpack_decoder.h"
#include "net/third_party/quiche/src/http2/hpack/decoder/hpack_decoder_listener.h"
#include "net/third_party/quiche/src/http2/hpack/decoder/hpack_decoder_tables.h"
#include "net/third_party/quiche/src/http2/hpack/hpack_string.h"
#include "net/third_party/quiche/src/http2/hpack/http2_hpack_constants.h"
#include "net/third_party/quiche/src/spdy/core/hpack/hpack_header_table.h"
#include "net/third_party/quiche/src/spdy/core/spdy_header_block.h"
#include "net/third_party/quiche/src/spdy/core/spdy_headers_handler_interface.h"
#include "net/third_party/quiche/src/spdy/platform/api/spdy_export.h"
#include "net/third_party/quiche/src/spdy/platform/api/spdy_string_piece.h"
namespace spdy {
namespace test {
class HpackDecoderAdapterPeer;
} // namespace test
class SPDY_EXPORT_PRIVATE HpackDecoderAdapter {
friend test::HpackDecoderAdapterPeer;
HpackDecoderAdapter(const HpackDecoderAdapter&) = delete;
HpackDecoderAdapter& operator=(const HpackDecoderAdapter&) = delete;
// Called upon acknowledgement of SETTINGS_HEADER_TABLE_SIZE.
void ApplyHeaderTableSizeSetting(size_t size_setting);
// If a SpdyHeadersHandlerInterface is provided, the decoder will emit
// headers to it rather than accumulating them in a SpdyHeaderBlock.
// Does not take ownership of the handler, but does use the pointer until
// the current HPACK block is completely decoded.
void HandleControlFrameHeadersStart(SpdyHeadersHandlerInterface* handler);
// Called as HPACK block fragments arrive. Returns false if an error occurred
// while decoding the block. Does not take ownership of headers_data.
bool HandleControlFrameHeadersData(const char* headers_data,
size_t headers_data_length);
// Called after a HPACK block has been completely delivered via
// HandleControlFrameHeadersData(). Returns false if an error occurred.
// |compressed_len| if non-null will be set to the size of the encoded
// buffered block that was accumulated in HandleControlFrameHeadersData(),
// to support subsequent calculation of compression percentage.
// Discards the handler supplied at the start of decoding the block.
// TODO(jamessynge): Determine if compressed_len is needed; it is used to
// produce UUMA stat Net.SpdyHpackDecompressionPercentage, but only for
// deprecated SPDY3.
bool HandleControlFrameHeadersComplete(size_t* compressed_len);
// Accessor for the most recently decoded headers block. Valid until the next
// call to HandleControlFrameHeadersData().
// TODO(birenroy): Remove this method when all users of HpackDecoder specify
// a SpdyHeadersHandlerInterface.
const SpdyHeaderBlock& decoded_block() const;
void SetHeaderTableDebugVisitor(
std::unique_ptr<HpackHeaderTable::DebugVisitorInterface> visitor);
// Set how much encoded data this decoder is willing to buffer.
// TODO(jamessynge): Resolve definition of this value, as it is currently
// too tied to a single implementation. We probably want to limit one or more
// of these: individual name or value strings, header entries, the entire
// header list, or the HPACK block; we probably shouldn't care about the size
// of individual transport buffers.
void set_max_decode_buffer_size_bytes(size_t max_decode_buffer_size_bytes);
size_t EstimateMemoryUsage() const;
class SPDY_EXPORT_PRIVATE ListenerAdapter
: public http2::HpackDecoderListener,
public http2::HpackDecoderTablesDebugListener {
~ListenerAdapter() override;
// If a SpdyHeadersHandlerInterface is provided, the decoder will emit
// headers to it rather than accumulating them in a SpdyHeaderBlock.
// Does not take ownership of the handler, but does use the pointer until
// the current HPACK block is completely decoded.
void set_handler(SpdyHeadersHandlerInterface* handler);
const SpdyHeaderBlock& decoded_block() const { return decoded_block_; }
void SetHeaderTableDebugVisitor(
std::unique_ptr<HpackHeaderTable::DebugVisitorInterface> visitor);
// Override the HpackDecoderListener methods:
void OnHeaderListStart() override;
void OnHeader(http2::HpackEntryType entry_type,
const http2::HpackString& name,
const http2::HpackString& value) override;
void OnHeaderListEnd() override;
void OnHeaderErrorDetected(SpdyStringPiece error_message) override;
// Override the HpackDecoderTablesDebugListener methods:
int64_t OnEntryInserted(const http2::HpackStringPair& entry,
size_t insert_count) override;
void OnUseEntry(const http2::HpackStringPair& entry,
size_t insert_count,
int64_t insert_time) override;
void AddToTotalHpackBytes(size_t delta) { total_hpack_bytes_ += delta; }
size_t total_hpack_bytes() const { return total_hpack_bytes_; }
// If the caller doesn't provide a handler, the header list is stored in
// this SpdyHeaderBlock.
SpdyHeaderBlock decoded_block_;
// If non-NULL, handles decoded headers. Not owned.
SpdyHeadersHandlerInterface* handler_;
// Total bytes that have been received as input (i.e. HPACK encoded)
// in the current HPACK block.
size_t total_hpack_bytes_;
// Total bytes of the name and value strings in the current HPACK block.
size_t total_uncompressed_bytes_;
// visitor_ is used by a QUIC experiment regarding HPACK; remove
// when the experiment is done.
std::unique_ptr<HpackHeaderTable::DebugVisitorInterface> visitor_;
// Converts calls to HpackDecoderListener into calls to
// SpdyHeadersHandlerInterface.
ListenerAdapter listener_adapter_;
// The actual decoder.
http2::HpackDecoder hpack_decoder_;
// How much encoded data this decoder is willing to buffer.
size_t max_decode_buffer_size_bytes_;
// Flag to keep track of having seen the header block start. Needed at the
// moment because HandleControlFrameHeadersStart won't be called if a handler
// is not being provided by the caller.
bool header_block_started_;
} // namespace spdy