std::unique_ptr BaseQLogger::createPacketEvent()

in quic/logging/BaseQLogger.cpp [86:203]
115 lines of code
21 McCabe index (conditional complexity)

std::unique_ptr<QLogPacketEvent> BaseQLogger::createPacketEvent(
    const RegularQuicPacket& regularPacket,
    uint64_t packetSize) {
  auto event = std::make_unique<QLogPacketEvent>();
  event->refTime = std::chrono::duration_cast<std::chrono::microseconds>(
      std::chrono::steady_clock::now().time_since_epoch());
  event->packetSize = packetSize;
  event->eventType = QLogEventType::PacketReceived;
  const ShortHeader* shortHeader = regularPacket.header.asShort();
  if (shortHeader) {
    event->packetType = kShortHeaderPacketType.toString();
  } else {
    event->packetType =
        toQlogString(regularPacket.header.asLong()->getHeaderType()).str();
  }
  if (event->packetType != toString(LongHeader::Types::Retry)) {
    // A Retry packet does not include a packet number.
    event->packetNum = regularPacket.header.getPacketSequenceNum();
  }

  uint64_t numPaddingFrames = 0;
  // looping through the packet to store logs created from frames in the packet
  for (const auto& quicFrame : regularPacket.frames) {
    switch (quicFrame.type()) {
      case QuicFrame::Type::PaddingFrame: {
        ++numPaddingFrames;
        break;
      }
      case QuicFrame::Type::RstStreamFrame: {
        const auto& frame = *quicFrame.asRstStreamFrame();
        event->frames.push_back(std::make_unique<RstStreamFrameLog>(
            frame.streamId, frame.errorCode, frame.offset));
        break;
      }
      case QuicFrame::Type::ConnectionCloseFrame: {
        const auto& frame = *quicFrame.asConnectionCloseFrame();
        event->frames.push_back(std::make_unique<ConnectionCloseFrameLog>(
            frame.errorCode, frame.reasonPhrase, frame.closingFrameType));
        break;
      }
      case QuicFrame::Type::MaxDataFrame: {
        const auto& frame = *quicFrame.asMaxDataFrame();
        event->frames.push_back(
            std::make_unique<MaxDataFrameLog>(frame.maximumData));
        break;
      }
      case QuicFrame::Type::MaxStreamDataFrame: {
        const auto& frame = *quicFrame.asMaxStreamDataFrame();
        event->frames.push_back(std::make_unique<MaxStreamDataFrameLog>(
            frame.streamId, frame.maximumData));
        break;
      }
      case QuicFrame::Type::DataBlockedFrame: {
        const auto& frame = *quicFrame.asDataBlockedFrame();
        event->frames.push_back(
            std::make_unique<DataBlockedFrameLog>(frame.dataLimit));
        break;
      }
      case QuicFrame::Type::StreamDataBlockedFrame: {
        const auto& frame = *quicFrame.asStreamDataBlockedFrame();
        event->frames.push_back(std::make_unique<StreamDataBlockedFrameLog>(
            frame.streamId, frame.dataLimit));
        break;
      }
      case QuicFrame::Type::StreamsBlockedFrame: {
        const auto& frame = *quicFrame.asStreamsBlockedFrame();
        event->frames.push_back(std::make_unique<StreamsBlockedFrameLog>(
            frame.streamLimit, frame.isForBidirectional));
        break;
      }
      case QuicFrame::Type::ReadAckFrame: {
        const auto& frame = *quicFrame.asReadAckFrame();
        event->frames.push_back(
            std::make_unique<ReadAckFrameLog>(frame.ackBlocks, frame.ackDelay));
        break;
      }
      case QuicFrame::Type::ReadStreamFrame: {
        const auto& frame = *quicFrame.asReadStreamFrame();
        event->frames.push_back(std::make_unique<StreamFrameLog>(
            frame.streamId, frame.offset, frame.data->length(), frame.fin));
        break;
      }
      case QuicFrame::Type::ReadCryptoFrame: {
        const auto& frame = *quicFrame.asReadCryptoFrame();
        event->frames.push_back(std::make_unique<CryptoFrameLog>(
            frame.offset, frame.data->length()));
        break;
      }
      case QuicFrame::Type::ReadNewTokenFrame: {
        event->frames.push_back(std::make_unique<ReadNewTokenFrameLog>());
        break;
      }
      case QuicFrame::Type::PingFrame: {
        event->frames.push_back(std::make_unique<quic::PingFrameLog>());
        break;
      }
      case QuicFrame::Type::QuicSimpleFrame: {
        const auto& simpleFrame = *quicFrame.asQuicSimpleFrame();
        addQuicSimpleFrameToEvent(event.get(), simpleFrame);
        break;
      }
      case QuicFrame::Type::NoopFrame: {
        break;
      }
      case QuicFrame::Type::DatagramFrame: {
        const auto& frame = *quicFrame.asDatagramFrame();
        event->frames.push_back(
            std::make_unique<quic::DatagramFrameLog>(frame.length));
        break;
      }
    }
  }
  if (numPaddingFrames > 0) {
    event->frames.push_back(
        std::make_unique<PaddingFrameLog>(numPaddingFrames));
  }
  return event;
}