Add a QUIC_FALLTHROUGH_INTENDED annotation to QUIC's platform API.

Merge internal change: 183282622

Change-Id: Ibef39b6e706ebd86972909504ce521b460f813ec
Reviewed-on: https://chromium-review.googlesource.com/886823
Commit-Queue: Ryan Hamilton <rch@chromium.org>
Reviewed-by: Zhongyi Shi <zhongyi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#532148}

net/BUILD.gn

@@ -1432,6 +1432,7 @@ component("net") {
       "quic/platform/api/quic_endian.h",
       "quic/platform/api/quic_estimate_memory_usage.h",
       "quic/platform/api/quic_export.h",
+      "quic/platform/api/quic_fallthrough.h",
       "quic/platform/api/quic_flag_utils.h",
       "quic/platform/api/quic_flags.h",
       "quic/platform/api/quic_hostname_utils.cc",
@@ -1472,6 +1473,7 @@ component("net") {
       "quic/platform/impl/quic_endian_impl.h",
       "quic/platform/impl/quic_estimate_memory_usage_impl.h",
       "quic/platform/impl/quic_export_impl.h",
+      "quic/platform/impl/quic_fallthrough_impl.h",
       "quic/platform/impl/quic_flag_utils_impl.h",
       "quic/platform/impl/quic_flags_impl.cc",
       "quic/platform/impl/quic_flags_impl.h",

net/quic/core/congestion_control/bbr_sender.cc

@@ -10,6 +10,7 @@
 #include "net/quic/core/congestion_control/rtt_stats.h"
 #include "net/quic/core/crypto/crypto_protocol.h"
 #include "net/quic/platform/api/quic_bug_tracker.h"
+#include "net/quic/platform/api/quic_fallthrough.h"
 #include "net/quic/platform/api/quic_flag_utils.h"
 #include "net/quic/platform/api/quic_flags.h"
 #include "net/quic/platform/api/quic_logging.h"
@@ -613,7 +614,7 @@ void BbrSender::UpdateRecoveryState(QuicPacketNumber last_acked_packet,
       if (is_round_start) {
         recovery_state_ = GROWTH;
       }
-      FALLTHROUGH;
+      QUIC_FALLTHROUGH_INTENDED;
 
     case GROWTH:
       // Exit recovery if appropriate.

net/quic/core/congestion_control/send_algorithm_interface.cc

@@ -8,6 +8,7 @@
 #include "net/quic/core/congestion_control/tcp_cubic_sender_bytes.h"
 #include "net/quic/core/quic_packets.h"
 #include "net/quic/platform/api/quic_bug_tracker.h"
+#include "net/quic/platform/api/quic_fallthrough.h"
 #include "net/quic/platform/api/quic_flag_utils.h"
 #include "net/quic/platform/api/quic_flags.h"
 #include "net/quic/platform/api/quic_pcc_sender.h"
@@ -38,7 +39,7 @@ SendAlgorithmInterface* SendAlgorithmInterface::Create(
                                max_congestion_window);
       }
       // Fall back to CUBIC if PCC is disabled.
-      FALLTHROUGH;
+      QUIC_FALLTHROUGH_INTENDED;
     case kCubicBytes:
       return new TcpCubicSenderBytes(
           clock, rtt_stats, false /* don't use Reno */,

net/quic/core/crypto/crypto_framer.cc

@@ -8,6 +8,7 @@
 #include "net/quic/core/quic_data_reader.h"
 #include "net/quic/core/quic_data_writer.h"
 #include "net/quic/core/quic_packets.h"
+#include "net/quic/platform/api/quic_fallthrough.h"
 #include "net/quic/platform/api/quic_str_cat.h"
 #include "net/quic/platform/api/quic_string_piece.h"
 
@@ -245,7 +246,7 @@ QuicErrorCode CryptoFramer::Process(QuicStringPiece input,
       reader.ReadTag(&message_tag);
       message_.set_tag(message_tag);
       state_ = STATE_READING_NUM_ENTRIES;
-      FALLTHROUGH;
+      QUIC_FALLTHROUGH_INTENDED;
     case STATE_READING_NUM_ENTRIES:
       if (reader.BytesRemaining() < kNumEntriesSize + sizeof(uint16_t)) {
         break;
@@ -261,7 +262,7 @@ QuicErrorCode CryptoFramer::Process(QuicStringPiece input,
       tags_and_lengths_.reserve(num_entries_);
       state_ = STATE_READING_TAGS_AND_LENGTHS;
       values_len_ = 0;
-      FALLTHROUGH;
+      QUIC_FALLTHROUGH_INTENDED;
     case STATE_READING_TAGS_AND_LENGTHS: {
       if (reader.BytesRemaining() <
           num_entries_ * (kQuicTagSize + kCryptoEndOffsetSize)) {
@@ -295,7 +296,7 @@ QuicErrorCode CryptoFramer::Process(QuicStringPiece input,
       }
       values_len_ = last_end_offset;
       state_ = STATE_READING_VALUES;
-      FALLTHROUGH;
+      QUIC_FALLTHROUGH_INTENDED;
     }
     case STATE_READING_VALUES:
       if (reader.BytesRemaining() < values_len_) {

net/quic/core/crypto/quic_crypto_server_config.cc

@@ -35,6 +35,7 @@
 #include "net/quic/platform/api/quic_bug_tracker.h"
 #include "net/quic/platform/api/quic_clock.h"
 #include "net/quic/platform/api/quic_endian.h"
+#include "net/quic/platform/api/quic_fallthrough.h"
 #include "net/quic/platform/api/quic_flag_utils.h"
 #include "net/quic/platform/api/quic_flags.h"
 #include "net/quic/platform/api/quic_hostname_utils.h"
@@ -815,7 +816,7 @@ void QuicCryptoServerConfig::ProcessClientHelloAfterGetProof(
                               &params->token_binding_key_param, nullptr)) {
           break;
         }
-        FALLTHROUGH;
+        QUIC_FALLTHROUGH_INTENDED;
       default:
         helper.Fail(QUIC_INVALID_CRYPTO_MESSAGE_PARAMETER,
                     "Invalid Token Binding key parameter");

net/quic/core/quic_framer.cc

@@ -22,6 +22,7 @@
 #include "net/quic/core/quic_utils.h"
 #include "net/quic/platform/api/quic_aligned.h"
 #include "net/quic/platform/api/quic_bug_tracker.h"
+#include "net/quic/platform/api/quic_fallthrough.h"
 #include "net/quic/platform/api/quic_flag_utils.h"
 #include "net/quic/platform/api/quic_flags.h"
 #include "net/quic/platform/api/quic_logging.h"
@@ -417,7 +418,8 @@ size_t QuicFramer::BuildDataPacket(const QuicPacketHeader& header,
         }
         break;
       case MTU_DISCOVERY_FRAME:
-      // MTU discovery frames are serialized as ping frames.
+        // MTU discovery frames are serialized as ping frames.
+        QUIC_FALLTHROUGH_INTENDED;
       case PING_FRAME:
         // Ping has no payload.
         break;
@@ -1884,7 +1886,8 @@ size_t QuicFramer::ComputeFrameLength(
       return GetStopWaitingFrameSize(version_.transport_version,
                                      packet_number_length);
     case MTU_DISCOVERY_FRAME:
-    // MTU discovery frames are serialized as ping frames.
+      // MTU discovery frames are serialized as ping frames.
+      QUIC_FALLTHROUGH_INTENDED;
     case PING_FRAME:
       // Ping has no payload.
       return kQuicFrameTypeSize;

net/quic/core/quic_spdy_session.cc

@@ -11,6 +11,7 @@
 
 #include "net/quic/core/quic_headers_stream.h"
 #include "net/quic/platform/api/quic_bug_tracker.h"
+#include "net/quic/platform/api/quic_fallthrough.h"
 #include "net/quic/platform/api/quic_flag_utils.h"
 #include "net/quic/platform/api/quic_flags.h"
 #include "net/quic/platform/api/quic_logging.h"
@@ -153,7 +154,7 @@ class QuicSpdySession::SpdyFramerVisitor
         if (GetQuicReloadableFlag(quic_send_max_header_list_size)) {
           break;
         }
-        FALLTHROUGH;
+        QUIC_FALLTHROUGH_INTENDED;
       default:
         CloseConnection(
             QuicStrCat("Unsupported field of HTTP/2 SETTINGS frame: ", id),

net/quic/http/decoder/payload_decoders/quic_http_altsvc_payload_decoder.cc

@@ -13,6 +13,7 @@
 #include "net/quic/http/quic_http_constants.h"
 #include "net/quic/http/quic_http_structures.h"
 #include "net/quic/platform/api/quic_bug_tracker.h"
+#include "net/quic/platform/api/quic_fallthrough.h"
 
 namespace net {
 
@@ -74,7 +75,7 @@ QuicHttpAltSvcQuicHttpPayloadDecoder::ResumeDecodingPayload(
     switch (payload_state_) {
       case PayloadState::kStartDecodingStruct:
         status = state->StartDecodingStructureInPayload(&altsvc_fields_, db);
-        FALLTHROUGH;
+        QUIC_FALLTHROUGH_INTENDED;
 
       case PayloadState::kMaybeDecodedStruct:
         if (status == QuicHttpDecodeStatus::kDecodeDone &&
@@ -96,7 +97,7 @@ QuicHttpAltSvcQuicHttpPayloadDecoder::ResumeDecodingPayload(
           DCHECK_GT(altsvc_fields_.origin_length, state->remaining_payload());
           return state->ReportFrameSizeError();
         }
-        FALLTHROUGH;
+        QUIC_FALLTHROUGH_INTENDED;
 
       case PayloadState::kDecodingStrings:
         return DecodeStrings(state, db);

net/quic/http/decoder/payload_decoders/quic_http_data_payload_decoder.cc

@@ -15,6 +15,7 @@
 #include "net/quic/http/quic_http_constants.h"
 #include "net/quic/http/quic_http_structures.h"
 #include "net/quic/platform/api/quic_bug_tracker.h"
+#include "net/quic/platform/api/quic_fallthrough.h"
 
 namespace net {
 
@@ -103,7 +104,7 @@ QuicHttpDecodeStatus QuicHttpDataQuicHttpPayloadDecoder::ResumeDecodingPayload(
       if (status != QuicHttpDecodeStatus::kDecodeDone) {
         return status;
       }
-      FALLTHROUGH;
+      QUIC_FALLTHROUGH_INTENDED;
 
     case PayloadState::kReadPayload:
       avail = state->AvailablePayload(db);
@@ -116,7 +117,7 @@ QuicHttpDecodeStatus QuicHttpDataQuicHttpPayloadDecoder::ResumeDecodingPayload(
         payload_state_ = PayloadState::kReadPayload;
         return QuicHttpDecodeStatus::kDecodeInProgress;
       }
-      FALLTHROUGH;
+      QUIC_FALLTHROUGH_INTENDED;
 
     case PayloadState::kSkipPadding:
       // SkipPadding handles the OnPadding callback.

net/quic/http/decoder/payload_decoders/quic_http_goaway_payload_decoder.cc

@@ -13,6 +13,7 @@
 #include "net/quic/http/quic_http_constants.h"
 #include "net/quic/http/quic_http_structures.h"
 #include "net/quic/platform/api/quic_bug_tracker.h"
+#include "net/quic/platform/api/quic_fallthrough.h"
 
 namespace net {
 
@@ -77,7 +78,7 @@ QuicHttpGoAwayQuicHttpPayloadDecoder::ResumeDecodingPayload(
     switch (payload_state_) {
       case PayloadState::kStartDecodingFixedFields:
         status = state->StartDecodingStructureInPayload(&goaway_fields_, db);
-        FALLTHROUGH;
+        QUIC_FALLTHROUGH_INTENDED;
 
       case PayloadState::kHandleFixedFieldsStatus:
         if (status == QuicHttpDecodeStatus::kDecodeDone) {
@@ -95,7 +96,7 @@ QuicHttpGoAwayQuicHttpPayloadDecoder::ResumeDecodingPayload(
           payload_state_ = PayloadState::kResumeDecodingFixedFields;
           return status;
         }
-        FALLTHROUGH;
+        QUIC_FALLTHROUGH_INTENDED;
 
       case PayloadState::kReadOpaqueData:
         // The opaque data is all the remains to be decoded, so anything left

net/quic/http/decoder/payload_decoders/quic_http_headers_payload_decoder.cc

@@ -15,6 +15,7 @@
 #include "net/quic/http/quic_http_constants.h"
 #include "net/quic/http/quic_http_structures.h"
 #include "net/quic/platform/api/quic_bug_tracker.h"
+#include "net/quic/platform/api/quic_fallthrough.h"
 
 namespace net {
 
@@ -138,7 +139,7 @@ QuicHttpHeadersQuicHttpPayloadDecoder::ResumeDecodingPayload(
           payload_state_ = PayloadState::kReadPayload;
           continue;
         }
-        FALLTHROUGH;
+        QUIC_FALLTHROUGH_INTENDED;
 
       case PayloadState::kStartDecodingPriorityFields:
         status = state->StartDecodingStructureInPayload(&priority_fields_, db);
@@ -147,7 +148,7 @@ QuicHttpHeadersQuicHttpPayloadDecoder::ResumeDecodingPayload(
           return status;
         }
         state->listener()->OnHeadersPriority(priority_fields_);
-        FALLTHROUGH;
+        QUIC_FALLTHROUGH_INTENDED;
 
       case PayloadState::kReadPayload:
         avail = state->AvailablePayload(db);
@@ -160,7 +161,7 @@ QuicHttpHeadersQuicHttpPayloadDecoder::ResumeDecodingPayload(
           payload_state_ = PayloadState::kReadPayload;
           return QuicHttpDecodeStatus::kDecodeInProgress;
         }
-        FALLTHROUGH;
+        QUIC_FALLTHROUGH_INTENDED;
 
       case PayloadState::kSkipPadding:
         // SkipPadding handles the OnPadding callback.

net/quic/http/decoder/payload_decoders/quic_http_push_promise_payload_decoder.cc

@@ -15,6 +15,7 @@
 #include "net/quic/http/quic_http_constants.h"
 #include "net/quic/http/quic_http_structures.h"
 #include "net/quic/platform/api/quic_bug_tracker.h"
+#include "net/quic/platform/api/quic_fallthrough.h"
 
 namespace net {
 
@@ -101,7 +102,7 @@ QuicHttpPushPromiseQuicHttpPayloadDecoder::ResumeDecodingPayload(
           payload_state_ = PayloadState::kReadPadLength;
           return status;
         }
-        FALLTHROUGH;
+        QUIC_FALLTHROUGH_INTENDED;
 
       case PayloadState::kStartDecodingPushPromiseFields:
         status =
@@ -113,7 +114,7 @@ QuicHttpPushPromiseQuicHttpPayloadDecoder::ResumeDecodingPayload(
         // Finished decoding the Promised Stream ID. Can now tell the listener
         // that we're starting to decode a PUSH_PROMISE frame.
         ReportPushPromise(state);
-        FALLTHROUGH;
+        QUIC_FALLTHROUGH_INTENDED;
 
       case PayloadState::kReadPayload:
         DCHECK_LT(state->remaining_payload(), frame_header.payload_length);
@@ -136,7 +137,7 @@ QuicHttpPushPromiseQuicHttpPayloadDecoder::ResumeDecodingPayload(
           payload_state_ = PayloadState::kReadPayload;
           return QuicHttpDecodeStatus::kDecodeInProgress;
         }
-        FALLTHROUGH;
+        QUIC_FALLTHROUGH_INTENDED;
 
       case PayloadState::kSkipPadding:
         // SkipPadding handles the OnPadding callback.

net/quic/platform/api/quic_fallthrough.h

+// Copyright (c) 2018 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_QUIC_PLATFORM_API_QUIC_FALLTHROUGH_H_
+#define NET_QUIC_PLATFORM_API_QUIC_FALLTHROUGH_H_
+
+#include "net/quic/platform/impl/quic_fallthrough_impl.h"
+
+#define QUIC_FALLTHROUGH_INTENDED QUIC_FALLTHROUGH_INTENDED_IMPL
+
+#endif  // NET_QUIC_PLATFORM_API_QUIC_FALLTHROUGH_H_

net/quic/platform/impl/quic_fallthrough_impl.h

+// Copyright (c) 2018 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_QUIC_PLATFORM_IMPL_QUIC_FALLTHROUGH_IMPL_H_
+#define NET_QUIC_PLATFORM_IMPL_QUIC_FALLTHROUGH_IMPL_H_
+
+#define QUIC_FALLTHROUGH_INTENDED_IMPL FALLTHROUGH
+
+#endif  // NET_QUIC_PLATFORM_IMPL_QUIC_FALLTHROUGH_IMPL_H_