void NvmCacheState::restoreState()

in cachelib/allocator/NvmCacheState.cpp [102:138]
31 lines of code
11 McCabe index (conditional complexity)

void NvmCacheState::restoreState() {
  // Read previous instance state from nvm state file
  try {
    shouldDropNvmCache_ = fileExists(getFileNameFor(kShouldDropNvmCache));

    if (!fileExists(getFileNameFor(kNvmCacheState))) {
      // No nvm cache state supplied, we return early. Nvm cache will still be
      // started afresh due to wasCleanshutDown_ == false
      return;
    }

    auto metadata = loadMetadata(getFileNameFor(kNvmCacheState));
    wasCleanshutDown_ = *metadata.safeShutDown_ref();

    if (!shouldStartFresh()) {
      if (*metadata.nvmFormatVersion_ref() == kCacheNvmFormatVersion &&
          encryptionEnabled_ == *metadata.encryptionEnabled_ref() &&
          truncateAllocSize_ == *metadata.truncateAllocSize_ref()) {
        creationTime_ = *metadata.creationTime_ref();
      } else {
        XLOGF(ERR,
              "Expected nvm format version {}, but found {}. Expected "
              "encryption to be {}, but found {}. Expected truncateAllocSize "
              "to be {}, but found {}. Dropping NvmCache",
              kCacheNvmFormatVersion, *metadata.nvmFormatVersion_ref(),
              encryptionEnabled_ ? "true" : "false",
              *metadata.encryptionEnabled_ref() ? "true" : "false",
              truncateAllocSize_ ? "true" : "false",
              *metadata.truncateAllocSize_ref() ? "true" : "false");
        shouldDropNvmCache_ = true;
      }
    }
  } catch (const std::exception& ex) {
    XLOGF(ERR, "unable to deserialize nvm metadata file: {}", ex.what());
    shouldDropNvmCache_ = true;
  }
}