void FilterManager::encodeData(ActiveStreamEncoderFilter* filter, Buffer::Instance& data,
                               bool end_stream,
                               FilterIterationStartState filter_iteration_start_state) {
  filter_manager_callbacks_.resetIdleTimer();

  // Filter iteration may start at the current filter.
  std::list<ActiveStreamEncoderFilterPtr>::iterator entry =
      commonEncodePrefix(filter, end_stream, filter_iteration_start_state);
  auto trailers_added_entry = encoder_filters_.end();

  const bool trailers_exists_at_start = filter_manager_callbacks_.responseTrailers().has_value();
  for (; entry != encoder_filters_.end(); entry++) {
    if ((*entry)->skipFilter()) {
      continue;
    }
    // If the filter pointed by entry has stopped for all frame type, return now.
    if (handleDataIfStopAll(**entry, data, state_.encoder_filters_streaming_)) {
      return;
    }
    // If end_stream_ is marked for a filter, the data is not for this filter and filters after.
    // For details, please see the comment in the ActiveStream::decodeData() function.
    if ((*entry)->end_stream_) {
      return;
    }
    ASSERT(!(state_.filter_call_state_ & FilterCallState::EncodeData));

    // We check the response_trailers_ pointer here in case addEncodedTrailers
    // is called in encodeData during a previous filter invocation, at which point we communicate to
    // the current and future filters that the stream has not yet ended.
    state_.filter_call_state_ |= FilterCallState::EncodeData;
    if (end_stream) {
      state_.filter_call_state_ |= FilterCallState::LastDataFrame;
    }

    recordLatestDataFilter(entry, state_.latest_data_encoding_filter_, encoder_filters_);

    (*entry)->end_stream_ = end_stream && !filter_manager_callbacks_.responseTrailers();
    FilterDataStatus status = (*entry)->handle_->encodeData(data, (*entry)->end_stream_);
    if (state_.encoder_filter_chain_aborted_) {
      ENVOY_STREAM_LOG(trace, "encodeData filter iteration aborted due to local reply: filter={}",
                       *this, static_cast<const void*>((*entry).get()));
      status = FilterDataStatus::StopIterationNoBuffer;
    }
    if ((*entry)->end_stream_) {
      (*entry)->handle_->encodeComplete();
    }
    state_.filter_call_state_ &= ~FilterCallState::EncodeData;
    if (end_stream) {
      state_.filter_call_state_ &= ~FilterCallState::LastDataFrame;
    }
    ENVOY_STREAM_LOG(trace, "encode data called: filter={} status={}", *this,
                     static_cast<const void*>((*entry).get()), static_cast<uint64_t>(status));

    if (!trailers_exists_at_start && filter_manager_callbacks_.responseTrailers() &&
        trailers_added_entry == encoder_filters_.end()) {
      trailers_added_entry = entry;
    }

    if (!(*entry)->commonHandleAfterDataCallback(status, data, state_.encoder_filters_streaming_)) {
      return;
    }
  }

  const bool modified_end_stream = end_stream && trailers_added_entry == encoder_filters_.end();
  filter_manager_callbacks_.encodeData(data, modified_end_stream);
  if (state_.saw_downstream_reset_) {
    return;
  }
  maybeEndEncode(modified_end_stream);

  // If trailers were adding during encodeData we need to trigger decodeTrailers in order
  // to allow filters to process the trailers.
  if (trailers_added_entry != encoder_filters_.end()) {
    encodeTrailers(trailers_added_entry->get(), *filter_manager_callbacks_.responseTrailers());
  }
}
void FilterManager::encodeData(ActiveStreamEncoderFilter* filter, Buffer::Instance& data,
                               bool end_stream,
                               FilterIterationStartState filter_iteration_start_state) {
  filter_manager_callbacks_.resetIdleTimer();

   
  std::list<ActiveStreamEncoderFilterPtr>::iterator entry =
      commonEncodePrefix(filter, end_stream, filter_iteration_start_state);
  auto trailers_added_entry = encoder_filters_.end();

  const bool trailers_exists_at_start = filter_manager_callbacks_.responseTrailers().has_value();
  for (; entry != encoder_filters_.end(); entry++) {
    if ((*entry)->skipFilter()) {
      continue;
    }
     
    if (handleDataIfStopAll(**entry, data, state_.encoder_filters_streaming_)) {
      return;
    }
     
     
    if ((*entry)->end_stream_) {
      return;
    }
    ASSERT(!(state_.filter_call_state_ & FilterCallState::EncodeData));

     
     
     
    state_.filter_call_state_ |= FilterCallState::EncodeData;
    if (end_stream) {
      state_.filter_call_state_ |= FilterCallState::LastDataFrame;
    }

    recordLatestDataFilter(entry, state_.latest_data_encoding_filter_, encoder_filters_);

    (*entry)->end_stream_ = end_stream && !filter_manager_callbacks_.responseTrailers();
    FilterDataStatus status = (*entry)->handle_->encodeData(data, (*entry)->end_stream_);
    if (state_.encoder_filter_chain_aborted_) {
      ENVOY_STREAM_LOG(trace, "encodeData filter iteration aborted due to local reply: filter={}",
                       *this, static_cast<const void*>((*entry).get()));
      status = FilterDataStatus::StopIterationNoBuffer;
    }
    if ((*entry)->end_stream_) {
      (*entry)->handle_->encodeComplete();
    }
    state_.filter_call_state_ &= ~FilterCallState::EncodeData;
    if (end_stream) {
      state_.filter_call_state_ &= ~FilterCallState::LastDataFrame;
    }
    ENVOY_STREAM_LOG(trace, "encode data called: filter={} status={}", *this,
                     static_cast<const void*>((*entry).get()), static_cast<uint64_t>(status));

    if (!trailers_exists_at_start && filter_manager_callbacks_.responseTrailers() &&
        trailers_added_entry == encoder_filters_.end()) {
      trailers_added_entry = entry;
    }

    if (!(*entry)->commonHandleAfterDataCallback(status, data, state_.encoder_filters_streaming_)) {
      return;
    }
  }

  const bool modified_end_stream = end_stream && trailers_added_entry == encoder_filters_.end();
  filter_manager_callbacks_.encodeData(data, modified_end_stream);
  if (state_.saw_downstream_reset_) {
    return;
  }
  maybeEndEncode(modified_end_stream);

   
   
  if (trailers_added_entry != encoder_filters_.end()) {
    encodeTrailers(trailers_added_entry->get(), *filter_manager_callbacks_.responseTrailers());
  }
}