class FileStorageController

file_autoload_info in core/modules/file/file.module

Implements hook_autoload_info().

file_entity_info in core/modules/file/file.module

Implements hook_entity_info().

class FileStorageController extends EntityDatabaseStorageController {
  /**
   * Overrides EntityDatabaseStorageController::presave().
   *
   * @param File $entity
   *   The file entity about to be saved.
   */
  protected function preSave(EntityInterface $entity) {
    $entity->timestamp = REQUEST_TIME;
    $entity->filesize = filesize($entity->uri);
    if (!isset($entity->langcode)) {
      // Default the file's language code to none, because files are language
      // neutral more often than language dependent.
      $entity->langcode = LANGUAGE_NONE;
    }

    // The file type is used as a bundle key, and therefore, must not be NULL.
    // It defaults to FILE_TYPE_NONE when loaded via file_load(), but in case
    // file_save() is called on a new file object, default it here too.
    if (!isset($entity->type)) {
      $entity->type = FILE_TYPE_NONE;
    }

    // If the file isn't already assigned a real type, determine what type should
    // be assigned to it.
    if ($entity->type === FILE_TYPE_NONE) {
      $type = file_get_type($entity);
      if (isset($type)) {
        $entity->type = $type;
      }
    }
  }

  /**
   * Overrides EntityDatabaseStorageController::preDelete().
   *
   * @param File[] $entities
   *   The file entities about to be deleted.
   */
  public function preDelete($entities) {
    foreach ($entities as $entity) {
      // Delete the actual file. Failures due to invalid files and files that
      // were already deleted are logged to watchdog but ignored, the
      // corresponding file entity will be deleted.
      file_unmanaged_delete($entity->uri);
    }
    // Delete corresponding file usage entries.
    db_delete('file_usage')
      ->condition('fid', array_keys($entities), 'IN')
      ->execute();
  }

  /**
   * Implements EntityControllerInterface::buildContent().
   */
  public function buildContent(EntityInterface $file, $view_mode = 'full', $langcode = NULL) {
    global $language_content;
    $langcode = $langcode ? $langcode : $language_content->langcode;

    // Remove previously built content, if exists.
    $file->content = array();

    // In case of a multiple view, file_view_multiple() already ran the
    // 'prepare_view' step. An internal flag prevents the operation from running
    // twice.
    // Allow modules to change the view mode.
    $view_mode = key(entity_view_mode_prepare('file', array($file->fid => $file), $view_mode, $langcode));
    field_attach_prepare_view('file', array($file->fid => $file), $view_mode, $langcode);
    entity_prepare_view('file', array($file->fid => $file), $langcode);

    // Build the actual file display.
    $file->content['file'] = file_view_file($file, $view_mode, $langcode);

    // Build fields content.
    $file->content += field_attach_view('file', $file, $view_mode, $langcode);

    $links = array();
    $file->content['links'] = array(
      '#theme' => 'links__file',
      '#pre_render' => array('backdrop_pre_render_links'),
      '#attributes' => array('class' => array('links', 'inline')),
    );
    $file->content['links']['file'] = array(
      '#theme' => 'links__file__file',
      '#links' => $links,
      '#attributes' => array('class' => array('links', 'inline')),
    );

    // Allow modules to make their own additions to the file.
    module_invoke_all('file_view', $file, $view_mode, $langcode);
    module_invoke_all('entity_view', $file, 'file', $view_mode, $langcode);
  }

  /**
   * Overrides DefaultEntityController::view().
   */
  public function view($files, $view_mode = 'full', $langcode = NULL, $page = NULL) {
    global $language_content;
    $langcode = $langcode ? $langcode : $language_content->langcode;

    $view = array();
    foreach ($files as $file) {
      /* @var File $file */
      // Populate $file->content with a render() array.
      $this->buildContent($file, $view_mode, $langcode);

      $build = $file->content;
      // We don't need duplicate rendering info in $file->content.
      unset($file->content);

      $build += array(
        '#theme' => 'file_entity',
        '#file' => $file,
        '#view_mode' => $view_mode,
        '#language' => $langcode,
        '#page' => $page,
      );

      // Add contextual links for this file, except when the file is already
      // being displayed on its own page. Modules may alter this behavior (for
      // example, to restrict contextual links to certain view modes) by
      // implementing hook_file_view_alter().
      if (!empty($file->fid) && !($view_mode == 'full' && file_is_page($file))) {
        $build['#contextual_links']['file'] = array('file', array($file->fid));
      }

      // Allow modules to modify the structured file.
      $type = 'file';
      backdrop_alter(array('file_view', 'entity_view'), $build, $type);
      $view[$type][$file->id()] = $build;
    }

    return $view;
  }

}