bool IOBuf::empty() const {
  const IOBuf* current = this;
  do {
    if (current->length() != 0) {
      return false;
    }
    current = current->next_;
  } while (current != this);
  return true;
}
bool IOBuf::empty() const {
  const IOBuf* current = this;
  do {
    if (current->length() != 0) {
      return false;
    }
    current = current->next_;
  } while (current != this);
  return true;
}