void Recovery::ReadLogsFromFiles()

in platform/consensus/recovery/recovery.cpp [453:528]
69 lines of code
13 McCabe index (conditional complexity)

void Recovery::ReadLogsFromFiles(
    const std::string& path, int64_t ckpt, int file_idx,
    std::function<void(const SystemInfoData& data)> system_callback,
    std::function<void(std::unique_ptr<Context> context,
                       std::unique_ptr<Request> request)>
        call_back) {
  int fd = open(path.c_str(), O_CREAT | O_RDONLY, 0666);
  if (fd < 0) {
    LOG(ERROR) << " open file fail:" << path;
  }
  LOG(INFO) << "read logs:" << path << " pos:" << lseek(fd, 0, SEEK_CUR);
  assert(fd >= 0);

  size_t data_len = 0;
  Read(fd, sizeof(data_len), reinterpret_cast<char*>(&data_len));
  {
    std::string data;
    char* buf = new char[data_len];
    if (!Read(fd, data_len, buf)) {
      LOG(ERROR) << "Read system info fail";
      return;
    }
    data = std::string(buf, data_len);
    delete buf;
    std::vector<std::string> data_list = ParseRawData(data);

    SystemInfoData info;
    if (data_list.empty() || !info.ParseFromString(data_list[0])) {
      LOG(ERROR) << "parse info fail:" << data.size();
      return;
    }
    LOG(INFO) << "read system info:" << info.DebugString();
    if (file_idx == 0) {
      system_callback(info);
    }
  }

  std::vector<std::unique_ptr<RecoveryData>> request_list;

  while (Read(fd, sizeof(data_len), reinterpret_cast<char*>(&data_len))) {
    std::string data;
    char* buf = new char[data_len];
    if (!Read(fd, data_len, buf)) {
      LOG(ERROR) << "Read data log fail";
      break;
    }
    data = std::string(buf, data_len);
    delete buf;

    std::vector<std::unique_ptr<RecoveryData>> list = ParseData(data);
    if (list.size() == 0) {
      request_list.clear();
      break;
    }
    for (auto& l : list) {
      request_list.push_back(std::move(l));
    }
  }
  if (request_list.size() == 0) {
    ftruncate(fd, 0);
  }
  uint64_t max_seq = 0;
  for (std::unique_ptr<RecoveryData>& recovery_data : request_list) {
    if (ckpt < recovery_data->request->seq()) {
      recovery_data->request->set_is_recovery(true);
      max_seq = recovery_data->request->seq();
      call_back(std::move(recovery_data->context),
                std::move(recovery_data->request));
    }
  }

  LOG(ERROR) << "read log from files:" << path << " done"
             << " recovery max seq:" << max_seq;

  close(fd);
}