if (!status.ok()) GTEST_SKIP() << "Append() not supported: " << status;
  status = new_file->Flush();
  if (!status.ok()) GTEST_SKIP() << "Flush() not supported: " << status;
  status = new_file->Close();
  if (!status.ok()) GTEST_SKIP() << "Close() not supported: " << status;

  std::unique_ptr<ReadOnlyMemoryRegion> region;
  status = env_->NewReadOnlyMemoryRegionFromFile(filepath, &region);

  return StatusFromTF_Status(plugin_status.get());
}

Status ModularWritableFile::Close() {
  if (ops_->close == nullptr)
    return errors::Unimplemented(
        tensorflow::strings::StrCat("Close() not implemented for ", filename_));

  UniquePtrTo_TF_Status plugin_status(TF_NewStatus(), TF_DeleteStatus);
  ops_->close(file_.get(), plugin_status.get());
  return StatusFromTF_Status(plugin_status.get());
}

// to allow their size to be computed and they need to be passable to a backward
// function and deleted (as the backprop code creates lots of gradients the user
// is not interested in).
//
// BackwardFunction needs to be a closure which stores intermediate activations
// from the forward computation and calls a vector-jacobian product function
// (also known as adjoint function) to compute, given downstream gradients,
// upstream gradients.
//

                    << filepath << ": " << TF_Message(s);

    TF_CloseWritableFile(handle, s);
    ASSERT_TF_OK(s) << "TF_CloseWritableFile failed to close handle to "
                    << filepath << ": " << TF_Message(s);

    TF_StringStream* children = TF_GetChildren(dirpath.c_str(), s);
    ASSERT_TF_OK(s) << "TF_GetChildren failed for " << dirpath;

  auto* cc_file = reinterpret_cast<::tensorflow::WritableFile*>(handle);
  TF_SetStatus(status, TF_OK, "");
  ::tensorflow::Set_TF_Status_from_Status(status, cc_file->Close());
  delete cc_file;
}

void TF_SyncWritableFile(TF_WritableFileHandle* handle, TF_Status* status) {
  auto* cc_file = reinterpret_cast<::tensorflow::WritableFile*>(handle);
  TF_SetStatus(status, TF_OK, "");

  if (dst_fd < 0) {
    close(src_fd);
    return -1;
  }

  // Both files have been opened, do the transfer.
  // Since errno would be overridden by `close` below, save it here.
  int error_code = 0;
  if (CopyFileContents(dst_fd, src_fd, size) < 0) error_code = errno;

  close(src_fd);
  close(dst_fd);
  if (error_code != 0) {
    errno = error_code;
    return -1;

TempFile::TempFile(TempFile&& rhs)
    : std::fstream(std::move(rhs)), name_(std::move(rhs.name_)) {}

TempFile::~TempFile() {
  std::fstream::close();
  std::remove(name_.c_str());
}

const std::string TempFile::getName() const { return name_; }

bool TempFile::truncate() {
  std::fstream::close();
  std::fstream::open(name_, std::ios::binary | std::ios::out);
  return std::fstream::is_open();

  } else {
    DCHECK_EQ(nullptr, session);
    return nullptr;
  }
}

void TF_CloseDeprecatedSession(TF_DeprecatedSession* s, TF_Status* status) {
  status->status = s->session->Close();
}

void TF_DeleteDeprecatedSession(TF_DeprecatedSession* s, TF_Status* status) {
  status->status = absl::OkStatus();
  if (s == nullptr) return;
  delete s->session;
  delete s;
}

      : filename_(filename), file_(std::move(file)), ops_(ops) {}

  ~ModularWritableFile() override { ops_->cleanup(file_.get()); }

  Status Append(StringPiece data) override;
  Status Close() override;
  Status Flush() override;
  Status Sync() override;
  Status Name(StringPiece* result) const override;
  Status Tell(int64_t* position) override;

 private:
  std::string filename_;

  Flush(file, status);
}

void Close(const TF_WritableFile* file, TF_Status* status) {
  auto gcs_file = static_cast<GCSFile*>(file->plugin_file);
  TF_VLog(3, "Close: gs://%s/%s", gcs_file->bucket.c_str(),
          gcs_file->object.c_str());
  if (gcs_file->sync_need) {
    Flush(file, status);
  }
  gcs_file->outfile.close();
}

}  // namespace tf_writable_file