void HTTPTransaction::resumeIngress()

in proxygen/lib/http/session/HTTPTransaction.cpp [1452:1520]
63 lines of code
18 McCabe index (conditional complexity)

void HTTPTransaction::resumeIngress() {
  VLOG(4) << "resumeIngress request " << *this;
  DestructorGuard g(this);
  if (!ingressPaused_ || isIngressComplete()) {
    VLOG(4) << "can't resume ingress, ingressPaused=" << ingressPaused_
            << ", ingressComplete=" << isIngressComplete()
            << ", inResume_=" << inResume_ << " " << *this;
    return;
  }
  ingressPaused_ = false;
  transport_.resumeIngress(this);
  if (inResume_) {
    VLOG(4) << "skipping recursive resume loop " << *this;
    return;
  }
  inResume_ = true;
  SCOPE_EXIT {
    updateReadTimeout();
    inResume_ = false;
  };

  if (deferredIngress_ && (maxDeferredIngress_ <= deferredIngress_->size())) {
    maxDeferredIngress_ = deferredIngress_->size();
  }

  // Process any deferred ingress callbacks
  // Note: we recheck the ingressPaused_ state because a callback
  // invoked by the resumeIngress() call above could have re-paused
  // the transaction.
  while (!ingressPaused_ && deferredIngress_ && !deferredIngress_->empty()) {
    HTTPEvent& callback(deferredIngress_->front());
    VLOG(5) << "Processing deferred ingress callback of type "
            << callback.getEvent() << " " << *this;
    SCOPE_EXIT {
      if (deferredIngress_) {
        deferredIngress_->pop();
      }
    };
    switch (callback.getEvent()) {
      case HTTPEvent::Type::MESSAGE_BEGIN:
        LOG(FATAL) << "unreachable";
        break;
      case HTTPEvent::Type::HEADERS_COMPLETE:
        processIngressHeadersComplete(callback.getHeaders());
        break;
      case HTTPEvent::Type::BODY: {
        unique_ptr<IOBuf> data = callback.getBody();
        auto len = data->computeChainDataLength();
        INVARIANT(recvWindow_.free(len));
        processIngressBody(std::move(data), len);
      } break;
      case HTTPEvent::Type::CHUNK_HEADER:
        processIngressChunkHeader(callback.getChunkLength());
        break;
      case HTTPEvent::Type::CHUNK_COMPLETE:
        processIngressChunkComplete();
        break;
      case HTTPEvent::Type::TRAILERS_COMPLETE:
        processIngressTrailers(callback.getTrailers());
        break;
      case HTTPEvent::Type::MESSAGE_COMPLETE:
        processIngressEOM();
        break;
      case HTTPEvent::Type::UPGRADE:
        processIngressUpgrade(callback.getUpgradeProtocol());
        break;
    }
  }
}