Remove HpackDecoder2.

Also remove associated flag FLAGS_chromium_http2_flag_spdy_use_hpack_decoder2.

HpackDecoder2 (an adapter to //gfe/http2/hpack/decoder) was superseded by
HpackDecoder3, and has not been used in production.

This CL lands server change 149561590 by jamessynge.

BUG=488484

Review-Url: https://codereview.chromium.org/2750853008
Cr-Commit-Position: refs/heads/master@{#457474}

net/BUILD.gn

@@ -1470,8 +1470,6 @@ component("net") {
       "spdy/hpack/hpack_constants.h",
       "spdy/hpack/hpack_decoder.cc",
       "spdy/hpack/hpack_decoder.h",
-      "spdy/hpack/hpack_decoder2.cc",
-      "spdy/hpack/hpack_decoder2.h",
       "spdy/hpack/hpack_decoder3.cc",
       "spdy/hpack/hpack_decoder3.h",
       "spdy/hpack/hpack_decoder_interface.h",
@@ -4611,7 +4609,6 @@ test("net_unittests") {
     "spdy/buffered_spdy_framer_unittest.cc",
     "spdy/fuzzing/hpack_fuzz_util_test.cc",
     "spdy/header_coalescer_test.cc",
-    "spdy/hpack/hpack_decoder2_test.cc",
     "spdy/hpack/hpack_decoder3_test.cc",
     "spdy/hpack/hpack_decoder_test.cc",
     "spdy/hpack/hpack_encoder_test.cc",

net/quic/core/quic_headers_stream_test.cc

@@ -150,13 +150,11 @@ std::ostream& operator<<(std::ostream& os, Http2DecoderChoice v) {
   return os;
 }
 
-enum HpackDecoderChoice { HPACK_DECODER_SPDY, HPACK_DECODER2, HPACK_DECODER3 };
+enum HpackDecoderChoice { HPACK_DECODER_SPDY, HPACK_DECODER3 };
 std::ostream& operator<<(std::ostream& os, HpackDecoderChoice v) {
   switch (v) {
     case HPACK_DECODER_SPDY:
       return os << "SPDY";
-    case HPACK_DECODER2:
-      return os << "HPACK_DECODER2";
     case HPACK_DECODER3:
       return os << "HPACK_DECODER3";
   }
@@ -191,15 +189,9 @@ struct TestParams {
     }
     switch (hpack_decoder) {
       case HPACK_DECODER_SPDY:
-        FLAGS_chromium_http2_flag_spdy_use_hpack_decoder2 = false;
-        FLAGS_chromium_http2_flag_spdy_use_hpack_decoder3 = false;
-        break;
-      case HPACK_DECODER2:
-        FLAGS_chromium_http2_flag_spdy_use_hpack_decoder2 = true;
         FLAGS_chromium_http2_flag_spdy_use_hpack_decoder3 = false;
         break;
       case HPACK_DECODER3:
-        FLAGS_chromium_http2_flag_spdy_use_hpack_decoder2 = false;
         FLAGS_chromium_http2_flag_spdy_use_hpack_decoder3 = true;
         break;
     }
@@ -407,13 +399,13 @@ class QuicHeadersStreamTest : public ::testing::TestWithParam<TestParamsTuple> {
 INSTANTIATE_TEST_CASE_P(
     Tests,
     QuicHeadersStreamTest,
-    ::testing::Combine(
-        ::testing::ValuesIn(AllSupportedVersions()),
-        ::testing::Values(Perspective::IS_CLIENT, Perspective::IS_SERVER),
+    ::testing::Combine(::testing::ValuesIn(AllSupportedVersions()),
+                       ::testing::Values(Perspective::IS_CLIENT,
+                                         Perspective::IS_SERVER),
                        ::testing::Values(HTTP2_DECODER_SPDY,
                                          HTTP2_DECODER_NESTED_SPDY,
                                          HTTP2_DECODER_NEW),
-        ::testing::Values(HPACK_DECODER_SPDY, HPACK_DECODER2, HPACK_DECODER3)));
+                       ::testing::Values(HPACK_DECODER_SPDY, HPACK_DECODER3)));
 
 TEST_P(QuicHeadersStreamTest, StreamId) {
   EXPECT_EQ(3u, headers_stream_->id());
@@ -755,8 +747,7 @@ TEST_P(QuicHeadersStreamTest, RespectHttp2SettingsFrameSupportedFields) {
   stream_frame_.data_buffer = frame.data();
   stream_frame_.data_length = frame.size();
   headers_stream_->OnStreamFrame(stream_frame_);
-  EXPECT_EQ(kTestHeaderTableSize,
-            QuicSpdySessionPeer::GetSpdyFramer(&session_)
+  EXPECT_EQ(kTestHeaderTableSize, QuicSpdySessionPeer::GetSpdyFramer(&session_)
                                       .header_encoder_table_size());
 }
 

net/spdy/hpack/hpack_decoder2.h

-// 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.
-
-#ifndef NET_SPDY_HPACK_HPACK_DECODER2_H_
-#define NET_SPDY_HPACK_HPACK_DECODER2_H_
-
-// HpackDecoder2
-
-// An HpackDecoder decodes header sets as outlined in
-// http://tools.ietf.org/html/rfc7541. This implementation uses the
-// new HpackBlockDecoder in //net/http2/hpack/
-
-#include <stddef.h>
-
-#include <memory>
-#include <string>
-
-#include "base/macros.h"
-#include "base/strings/string_piece.h"
-#include "net/base/net_export.h"
-#include "net/http2/hpack/decoder/hpack_block_decoder.h"
-#include "net/http2/hpack/decoder/hpack_decoder_string_buffer.h"
-#include "net/http2/hpack/decoder/hpack_entry_decoder_listener.h"
-#include "net/http2/hpack/http2_hpack_constants.h"
-#include "net/http2/hpack/huffman/http2_hpack_huffman_decoder.h"
-#include "net/spdy/hpack/hpack_constants.h"
-#include "net/spdy/hpack/hpack_decoder_interface.h"
-#include "net/spdy/hpack/hpack_header_table.h"
-#include "net/spdy/spdy_header_block.h"
-#include "net/spdy/spdy_headers_handler_interface.h"
-
-namespace net {
-namespace test {
-class HpackDecoder2Peer;
-}  // namespace test
-
-class NET_EXPORT_PRIVATE HpackDecoder2 : public HpackDecoderInterface,
-                                         HpackEntryDecoderListener {
- public:
-  friend test::HpackDecoder2Peer;
-  HpackDecoder2();
-  ~HpackDecoder2() override;
-
-  // Override the interface methods:
-
-  void ApplyHeaderTableSizeSetting(size_t size_setting) override;
-  void HandleControlFrameHeadersStart(
-      SpdyHeadersHandlerInterface* handler) override;
-  bool HandleControlFrameHeadersData(const char* headers_data,
-                                     size_t headers_data_length) override;
-  bool HandleControlFrameHeadersComplete(size_t* compressed_len) override;
-  const SpdyHeaderBlock& decoded_block() const override;
-  void SetHeaderTableDebugVisitor(
-      std::unique_ptr<HpackHeaderTable::DebugVisitorInterface> visitor)
-      override;
-  void set_max_decode_buffer_size_bytes(
-      size_t max_decode_buffer_size_bytes) override;
-  size_t EstimateMemoryUsage() const override;
-
- protected:
-  // Override the HpackEntryDecoderListener methods:
-
-  void OnIndexedHeader(size_t index) override;
-  void OnStartLiteralHeader(HpackEntryType entry_type,
-                            size_t maybe_name_index) override;
-  void OnNameStart(bool huffman_encoded, size_t len) override;
-  void OnNameData(const char* data, size_t len) override;
-  void OnNameEnd() override;
-  void OnValueStart(bool huffman_encoded, size_t len) override;
-  void OnValueData(const char* data, size_t len) override;
-  void OnValueEnd() override;
-  void OnDynamicTableSizeUpdate(size_t size) override;
-
- private:
-  // Called when a complete header entry has been decoded, with the name and
-  // value of the entry. If check_header_order_ is true, confirms that
-  // pseudo-headers don't appear after normal headers, else it treats the
-  // headers as malformed, as per sections 8.1.2.3. of the HTTP2 specification.
-  // Calls handler_->OnHeader() if there is a handler, else adds the header
-  // to decoded_block_.
-  void HandleHeaderRepresentation(base::StringPiece name,
-                                  base::StringPiece value);
-
-  // Reset state in preparation for decoding a new HPACK block. Does not reset
-  // the dynamic table.
-  void Reset();
-
-  // Called when an error is detected while decoding. Replaces the listener
-  // in the HpackBlockDecoder with the no-op listener.
-  void SetErrorDetected();
-
-  // Enforce the limit on the maximum size of strings that can be buffered.
-  // It happens that this test is made after the strings have been buffered,
-  // but that isn't a problem because we don't pass enormous buffers into
-  // HandleControlFrameHeadersData.
-  bool EnforceMaxDecodeBufferSize();
-
-  HpackHeaderTable header_table_;
-  SpdyHeaderBlock decoded_block_;
-
-  // Scratch space for storing decoded literals.
-  HpackDecoderStringBuffer name_, value_;
-
-  // If non-NULL, handles decoded headers.
-  SpdyHeadersHandlerInterface* handler_;
-
-  HpackEntryDecoderNoOpListener no_op_listener_;
-
-  // Total bytes that have been received as input (i.e. HPACK encoded).
-  size_t total_hpack_bytes_;
-
-  // Total bytes of the name and value strings in the current HPACK block.
-  size_t total_header_bytes_;
-
-  // How much encoded data this decoder is willing to buffer.
-  size_t max_decode_buffer_size_bytes_ = 32 * 1024;  // 32 KB
-
-  HpackBlockDecoder hpack_block_decoder_;
-
-  // Count of Dynamic Table Size Updates seen in the current HPACK block.
-  uint32_t size_update_count_;
-
-  // The type of the current header entry (with literals) that is being decoded.
-  HpackEntryType entry_type_;
-
-  // Has a header been seen in the current HPACK block?
-  bool header_seen_;
-
-  // Did the HpackBlockDecoder stop in the middle of an entry?
-  bool in_progress_;
-
-  // Has an error been detected while decoding the HPACK block?
-  bool error_detected_;
-
-  // 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.
-  // TODO(jamessynge): Consider collapsing several of these bools into a single
-  // enum representing the state of the decoding process.
-  bool header_block_started_;
-
-  DISALLOW_COPY_AND_ASSIGN(HpackDecoder2);
-};
-
-}  // namespace net
-#endif  // NET_SPDY_HPACK_HPACK_DECODER2_H_

net/spdy/spdy_flags.cc

@@ -12,9 +12,6 @@ bool FLAGS_chromium_http2_flag_log_compressed_size = true;
 // If true, remove use of SpdyFrameBuilder::OverwriteLength().
 bool FLAGS_chromium_http2_flag_remove_rewritelength = true;
 
-// Use //net/http2/hpack/decoder as HPACK entry decoder.
-bool FLAGS_chromium_http2_flag_spdy_use_hpack_decoder2 = false;
-
 // Use //net/http2/hpack/decoder as complete HPACK decoder.
 bool FLAGS_chromium_http2_flag_spdy_use_hpack_decoder3 = true;
 

net/spdy/spdy_flags.h

@@ -11,8 +11,6 @@ namespace net {
 
 NET_EXPORT_PRIVATE extern bool FLAGS_chromium_http2_flag_log_compressed_size;
 NET_EXPORT_PRIVATE extern bool FLAGS_chromium_http2_flag_remove_rewritelength;
-NET_EXPORT_PRIVATE extern bool
-    FLAGS_chromium_http2_flag_spdy_use_hpack_decoder2;
 NET_EXPORT_PRIVATE extern bool
     FLAGS_chromium_http2_flag_spdy_use_hpack_decoder3;
 NET_EXPORT_PRIVATE extern bool FLAGS_use_http2_frame_decoder_adapter;

net/spdy/spdy_framer.cc

@@ -25,7 +25,6 @@
 #include "net/quic/core/quic_flags.h"
 #include "net/spdy/hpack/hpack_constants.h"
 #include "net/spdy/hpack/hpack_decoder.h"
-#include "net/spdy/hpack/hpack_decoder2.h"
 #include "net/spdy/hpack/hpack_decoder3.h"
 #include "net/spdy/http2_frame_decoder_adapter.h"
 #include "net/spdy/platform/api/spdy_estimate_memory_usage.h"
@@ -2403,11 +2402,7 @@ HpackEncoder* SpdyFramer::GetHpackEncoder() {
 HpackDecoderInterface* SpdyFramer::GetHpackDecoder() {
   if (hpack_decoder_.get() == nullptr) {
     if (FLAGS_chromium_http2_flag_spdy_use_hpack_decoder3) {
-      SPDY_BUG_IF(FLAGS_chromium_http2_flag_spdy_use_hpack_decoder2)
-          << "Both alternate decoders are enabled.";
       hpack_decoder_.reset(new HpackDecoder3());
-    } else if (FLAGS_chromium_http2_flag_spdy_use_hpack_decoder2) {
-      hpack_decoder_.reset(new HpackDecoder2());
     } else {
       hpack_decoder_.reset(new HpackDecoder());
     }

net/spdy/spdy_framer_test.cc

@@ -636,7 +636,7 @@ StringPiece GetSerializedHeaders(const SpdySerializedFrame& frame,
 }
 
 enum DecoderChoice { DECODER_SELF, DECODER_NESTED, DECODER_HTTP2 };
-enum HpackChoice { HPACK_DECODER_1, HPACK_DECODER_2, HPACK_DECODER_3 };
+enum HpackChoice { HPACK_DECODER_1, HPACK_DECODER_3 };
 
 class SpdyFramerTest
     : public ::testing::TestWithParam<std::tuple<DecoderChoice, HpackChoice>> {
@@ -659,15 +659,9 @@ class SpdyFramerTest
     }
     switch (std::get<1>(param)) {
       case HPACK_DECODER_1:
-        FLAGS_chromium_http2_flag_spdy_use_hpack_decoder2 = false;
-        FLAGS_chromium_http2_flag_spdy_use_hpack_decoder3 = false;
-        break;
-      case HPACK_DECODER_2:
-        FLAGS_chromium_http2_flag_spdy_use_hpack_decoder2 = true;
         FLAGS_chromium_http2_flag_spdy_use_hpack_decoder3 = false;
         break;
       case HPACK_DECODER_3:
-        FLAGS_chromium_http2_flag_spdy_use_hpack_decoder2 = false;
         FLAGS_chromium_http2_flag_spdy_use_hpack_decoder3 = true;
         break;
     }
@@ -695,12 +689,13 @@ class SpdyFramerTest
   }
 };
 
-INSTANTIATE_TEST_CASE_P(
-    SpdyFramerTests,
+INSTANTIATE_TEST_CASE_P(SpdyFramerTests,
                         SpdyFramerTest,
-    ::testing::Combine(
-        ::testing::Values(DECODER_SELF, DECODER_NESTED, DECODER_HTTP2),
-        ::testing::Values(HPACK_DECODER_1, HPACK_DECODER_2, HPACK_DECODER_3)));
+                        ::testing::Combine(::testing::Values(DECODER_SELF,
+                                                             DECODER_NESTED,
+                                                             DECODER_HTTP2),
+                                           ::testing::Values(HPACK_DECODER_1,
+                                                             HPACK_DECODER_3)));
 
 // Test that we can encode and decode a SpdyHeaderBlock in serialized form.
 TEST_P(SpdyFramerTest, HeaderBlockInBuffer) {