void TransactionExecutor::PrepareMessage()

in platform/consensus/execution/transaction_executor.cpp [436:496]
40 lines of code
7 McCabe index (conditional complexity)

void TransactionExecutor::PrepareMessage() {
  while (!IsStop()) {
    std::unique_ptr<Request> request = prepare_queue_.Pop();
    if (request == nullptr) {
      continue;
    }

    uint64_t uid = request->uid();
    int current_f = SetFlag(uid, Start_Prepare);
    if (current_f == 0) {
      // commit has done
      // LOG(ERROR)<<" want prepare, commit started:"<<uid;
//      ClearPromise(uid);
      continue;
    }

    std::promise<int>* p = GetPromise(uid) ;
    assert(p);
    //LOG(ERROR)<<" prepare started:"<<uid;

    // LOG(ERROR)<<" prepare uid:"<<uid;

    // Execute the request, then send the response back to the user.
    std::unique_ptr<BatchUserRequest> batch_request =
        std::make_unique<BatchUserRequest>();
    if (!batch_request->ParseFromString(request->data())) {
      LOG(ERROR) << "parse data fail";
    }
    // batch_request = std::make_unique<BatchUserRequest>();
    batch_request->set_seq(request->seq());
    batch_request->set_hash(request->hash());
    batch_request->set_proxy_id(request->proxy_id());
    if (request->has_committed_certs()) {
      *batch_request->mutable_committed_certs() = request->committed_certs();
    }

    // LOG(ERROR)<<"prepare seq:"<<batch_request->seq()<<" proxy
    // id:"<<request->proxy_id()<<" local id:"<<batch_request->local_id();

    std::unique_ptr<std::vector<std::unique_ptr<google::protobuf::Message>>>
     request_v = transaction_manager_->Prepare(*batch_request);
    {
      std::unique_lock<std::mutex> lk(fd_mutex_[uid % mod]);
   //   assert(request_v);
      // assert(data_[uid%mod].find(uid) == data_[uid%mod].end());
      data_[uid%mod][uid] = std::move(request_v);
      req_[uid % mod][uid] = std::move(batch_request);
    }
    //LOG(ERROR)<<"set promise:"<<uid;
    p->set_value(1);
    {
      int set_ret = SetFlag(uid, End_Prepare);
      if (set_ret == 0) {
        // LOG(ERROR)<<"commit interrupt:"<<uid;
        //ClearPromise(uid);
      } else {
        //LOG(ERROR)<<"prepare done:"<<uid;
      }
    }
  }
}