bool JNIHelper::ReadFile()

in PlayAssetDelivery/NativeSample/common/ndk_helper/JNIHelper.cpp [133:195]
54 lines of code
7 McCabe index (conditional complexity)

bool JNIHelper::ReadFile(const char* fileName,
                         std::vector<uint8_t>* buffer_ref) {
  if (activity_ == NULL) {
    LOGI(
        "JNIHelper has not been initialized.Call init() to initialize the "
        "helper");
    return false;
  }

  // Lock mutex
  std::lock_guard<std::mutex> lock(mutex_);

  // First, try reading from externalFileDir;
  JNIEnv* env = AttachCurrentThread();
  jstring str_path = GetExternalFilesDirJString(env);

  std::string s;
  if(str_path) {
    const char* path = env->GetStringUTFChars(str_path, NULL);
    s = std::string(path);
    if (fileName[0] != '/') {
      s.append("/");
    }
    s.append(fileName);
    env->ReleaseStringUTFChars(str_path, path);
    env->DeleteLocalRef(str_path);
  }
  std::ifstream f(s.c_str(), std::ios::binary);
  activity_->vm->DetachCurrentThread();
  if (f) {
    LOGI("reading:%s", s.c_str());
    f.seekg(0, std::ifstream::end);
    int32_t fileSize = f.tellg();
    f.seekg(0, std::ifstream::beg);
    buffer_ref->reserve(fileSize);
    buffer_ref->assign(std::istreambuf_iterator<char>(f),
                       std::istreambuf_iterator<char>());
    f.close();
    return true;
  } else {
    // Fallback to assetManager
    AAssetManager* assetManager = activity_->assetManager;
    AAsset* assetFile =
        AAssetManager_open(assetManager, fileName, AASSET_MODE_BUFFER);
    if (!assetFile) {
      return false;
    }
    uint8_t* data = (uint8_t*)AAsset_getBuffer(assetFile);
    int32_t size = AAsset_getLength(assetFile);
    if (data == NULL) {
      AAsset_close(assetFile);

      LOGI("Failed to load:%s", fileName);
      return false;
    }

    buffer_ref->reserve(size);
    buffer_ref->assign(data, data + size);

    AAsset_close(assetFile);
    return true;
  }
}