file.module 37 KB
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<?php

/**
 * @file
 * Defines a "managed_file" Form API field and a "file" field for Field module.
 */

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use Drupal\entity\EntityFieldQuery;

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// Load all Field module hooks for File.
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require_once DRUPAL_ROOT . '/core/modules/file/file.field.inc';
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/**
 * Implements hook_help().
 */
function file_help($path, $arg) {
  switch ($path) {
    case 'admin/help#file':
      $output = '';
      $output .= '<h3>' . t('About') . '</h3>';
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      $output .= '<p>' . t('The File module defines a <em>File</em> field type for the Field module, which lets you manage and validate uploaded files attached to content on your site (see the <a href="@field-help">Field module help page</a> for more information about fields). For more information, see the online handbook entry for <a href="@file">File module</a>.', array('@field-help' => url('admin/help/field'), '@file' => 'http://drupal.org/documentation/modules/file')) . '</p>';
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      $output .= '<h3>' . t('Uses') . '</h3>';
      $output .= '<dl>';
      $output .= '<dt>' . t('Attaching files to content') . '</dt>';
      $output .= '<dd>' . t('The File module allows users to attach files to content (e.g., PDF files, spreadsheets, etc.), when a <em>File</em> field is added to a given content type using the <a href="@fieldui-help">Field UI module</a>. You can add validation options to your File field, such as specifying a maximum file size and allowed file extensions.', array('@fieldui-help' => url('admin/help/field_ui'))) . '</dd>';
      $output .= '<dt>' . t('Managing attachment display') . '</dt>';
      $output .= '<dd>' . t('When you attach a file to content, you can specify whether it is <em>listed</em> or not. Listed files are displayed automatically in a section at the bottom of your content; non-listed files are available for embedding in your content, but are not included in the list at the bottom.') . '</dd>';
      $output .= '<dt>' . t('Managing file locations') . '</dt>';
      $output .= '<dd>' . t("When you create a File field, you can specify a directory where the files will be stored, which can be within either the <em>public</em> or <em>private</em> files directory. Files in the public directory can be accessed directly through the web server; when public files are listed, direct links to the files are used, and anyone who knows a file's URL can download the file. Files in the private directory are not accessible directly through the web server; when private files are listed, the links are Drupal path requests. This adds to server load and download time, since Drupal must start up and resolve the path for each file download request, but allows for access restrictions.") . '</dd>';
      $output .= '</dl>';
      return $output;
  }
}

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/**
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 * Implements hook_menu().
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 */
function file_menu() {
  $items = array();

  $items['file/ajax'] = array(
    'page callback' => 'file_ajax_upload',
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    'delivery callback' => 'ajax_deliver',
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    'access arguments' => array('access content'),
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    'theme callback' => 'ajax_base_page_theme',
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    'type' => MENU_CALLBACK,
  );
  $items['file/progress'] = array(
    'page callback' => 'file_ajax_progress',
    'access arguments' => array('access content'),
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    'theme callback' => 'ajax_base_page_theme',
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    'type' => MENU_CALLBACK,
  );

  return $items;
}

/**
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 * Implements hook_element_info().
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 *
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 * The managed file element may be used anywhere in Drupal.
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 */
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function file_element_info() {
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  $file_path = drupal_get_path('module', 'file');
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  $types['managed_file'] = array(
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    '#input' => TRUE,
    '#process' => array('file_managed_file_process'),
    '#value_callback' => 'file_managed_file_value',
    '#element_validate' => array('file_managed_file_validate'),
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    '#pre_render' => array('file_managed_file_pre_render'),
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    '#theme' => 'file_managed_file',
    '#theme_wrappers' => array('form_element'),
    '#progress_indicator' => 'throbber',
    '#progress_message' => NULL,
    '#upload_validators' => array(),
    '#upload_location' => NULL,
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    '#size' => 22,
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    '#extended' => FALSE,
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    '#attached' => array(
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      'css' => array($file_path . '/file.admin.css'),
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      'js' => array($file_path . '/file.js'),
    ),
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  );
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  return $types;
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}

/**
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 * Implements hook_theme().
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 */
function file_theme() {
  return array(
    // file.module.
    'file_link' => array(
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      'variables' => array('file' => NULL, 'icon_directory' => NULL),
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    ),
    'file_icon' => array(
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      'variables' => array('file' => NULL, 'icon_directory' => NULL),
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    ),
    'file_managed_file' => array(
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      'render element' => 'element',
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    ),

    // file.field.inc.
    'file_widget' => array(
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      'render element' => 'element',
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    ),
    'file_widget_multiple' => array(
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      'render element' => 'element',
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    ),
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    'file_formatter_table' => array(
      'variables' => array('items' => NULL),
    ),
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    'file_upload_help' => array(
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      'variables' => array('description' => NULL, 'upload_validators' => NULL),
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    ),
  );
}

/**
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 * Implements hook_file_download().
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 *
 * This function takes an extra parameter $field_type so that it may
 * be re-used by other File-like modules, such as Image.
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 */
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function file_file_download($uri, $field_type = 'file') {
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  global $user;

  // Get the file record based on the URI. If not in the database just return.
  $files = file_load_multiple(array(), array('uri' => $uri));
  if (count($files)) {
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    foreach ($files as $item) {
      // Since some database servers sometimes use a case-insensitive comparison
      // by default, double check that the filename is an exact match.
      if ($item->uri === $uri) {
        $file = $item;
        break;
      }
    }
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  }
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  if (!isset($file)) {
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    return;
  }

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  // Find out which (if any) fields of this type contain the file.
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  $references = file_get_file_references($file, NULL, FIELD_LOAD_CURRENT, $field_type);
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  // Stop processing if there are no references in order to avoid returning
  // headers for files controlled by other modules. Make an exception for
  // temporary files where the host entity has not yet been saved (for example,
  // an image preview on a node/add form) in which case, allow download by the
  // file's owner.
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  if (empty($references) && ($file->status == FILE_STATUS_PERMANENT || $file->uid != $user->uid)) {
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      return;
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  }

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  // Default to allow access.
  $denied = FALSE;
  // Loop through all references of this file. If a reference explicitly allows
  // access to the field to which this file belongs, no further checks are done
  // and download access is granted. If a reference denies access, eventually
  // existing additional references are checked. If all references were checked
  // and no reference denied access, access is granted as well. If at least one
  // reference denied access, access is denied.
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  foreach ($references as $field_name => $field_references) {
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    foreach ($field_references as $entity_type => $type_references) {
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      foreach ($type_references as $id => $reference) {
        // Try to load $entity and $field.
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        $entity = entity_load($entity_type, $id);
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        $field = NULL;
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        if ($entity) {
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          // Load all fields for that entity.
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          $field_items = field_get_items($entity_type, $entity, $field_name);

          // Find the field item with the matching URI.
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          foreach ($field_items as $field_item) {
            if ($field_item['uri'] == $uri) {
              $field = field_info_field($field_name);
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              break;
            }
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          }
        }
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        // Check that $entity and $field were loaded successfully and check if
        // access to that field is not disallowed. If any of these checks fail,
        // stop checking access for this reference.
        if (empty($entity) || empty($field) || !field_access('view', $field, $entity_type, $entity)) {
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          $denied = TRUE;
          break;
        }

        // Invoke hook and collect grants/denies for download access.
        // Default to FALSE and let entities overrule this ruling.
        $grants = array('system' => FALSE);
        foreach (module_implements('file_download_access') as $module) {
          $grants = array_merge($grants, array($module => module_invoke($module, 'file_download_access', $field, $entity_type, $entity)));
        }
        // Allow other modules to alter the returned grants/denies.
        drupal_alter('file_download_access', $grants, $field, $entity_type, $entity);

        if (in_array(TRUE, $grants)) {
          // If TRUE is returned, access is granted and no further checks are
          // necessary.
          $denied = FALSE;
          break 3;
        }

        if (in_array(FALSE, $grants)) {
          // If an implementation returns FALSE, access to this entity is denied
          // but the file could belong to another entity to which the user might
          // have access. Continue with these.
          $denied = TRUE;
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        }
      }
    }
  }

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  // Access specifically denied.
  if ($denied) {
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    return -1;
  }

  // Access is granted.
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  $headers = file_get_content_headers($file);
  return $headers;
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}

/**
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 * Ajax callback: Processes file uploads and deletions.
 *
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 * This rebuilds the form element for a particular field item. As long as the
 * form processing is properly encapsulated in the widget element the form
 * should rebuild correctly using FAPI without the need for additional callbacks
 * or processing.
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 *
 * @see file_menu()
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 */
function file_ajax_upload() {
  $form_parents = func_get_args();
  $form_build_id = (string) array_pop($form_parents);

  if (empty($_POST['form_build_id']) || $form_build_id != $_POST['form_build_id']) {
    // Invalid request.
    drupal_set_message(t('An unrecoverable error occurred. The uploaded file likely exceeded the maximum file size (@size) that this server supports.', array('@size' => format_size(file_upload_max_size()))), 'error');
    $commands = array();
    $commands[] = ajax_command_replace(NULL, theme('status_messages'));
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    return array('#type' => 'ajax', '#commands' => $commands);
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  }

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  list($form, $form_state) = ajax_get_form();
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  if (!$form) {
    // Invalid form_build_id.
    drupal_set_message(t('An unrecoverable error occurred. Use of this form has expired. Try reloading the page and submitting again.'), 'error');
    $commands = array();
    $commands[] = ajax_command_replace(NULL, theme('status_messages'));
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    return array('#type' => 'ajax', '#commands' => $commands);
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  }

  // Get the current element and count the number of files.
  $current_element = $form;
  foreach ($form_parents as $parent) {
    $current_element = $current_element[$parent];
  }
  $current_file_count = isset($current_element['#file_upload_delta']) ? $current_element['#file_upload_delta'] : 0;

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  // Process user input. $form and $form_state are modified in the process.
  drupal_process_form($form['#form_id'], $form, $form_state);
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  // Retrieve the element to be rendered.
  foreach ($form_parents as $parent) {
    $form = $form[$parent];
  }

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  // Add the special Ajax class if a new file was added.
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  if (isset($form['#file_upload_delta']) && $current_file_count < $form['#file_upload_delta']) {
    $form[$current_file_count]['#attributes']['class'][] = 'ajax-new-content';
  }
  // Otherwise just add the new content class on a placeholder.
  else {
    $form['#suffix'] .= '<span class="ajax-new-content"></span>';
  }

  $output = theme('status_messages') . drupal_render($form);
  $js = drupal_add_js();
  $settings = call_user_func_array('array_merge_recursive', $js['settings']['data']);

  $commands = array();
  $commands[] = ajax_command_replace(NULL, $output, $settings);
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  return array('#type' => 'ajax', '#commands' => $commands);
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}

/**
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 * Ajax callback: Retrieves upload progress.
 *
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 * @param $key
 *   The unique key for this upload process.
 */
function file_ajax_progress($key) {
  $progress = array(
    'message' => t('Starting upload...'),
    'percentage' => -1,
  );

  $implementation = file_progress_implementation();
  if ($implementation == 'uploadprogress') {
    $status = uploadprogress_get_info($key);
    if (isset($status['bytes_uploaded']) && !empty($status['bytes_total'])) {
      $progress['message'] = t('Uploading... (@current of @total)', array('@current' => format_size($status['bytes_uploaded']), '@total' => format_size($status['bytes_total'])));
      $progress['percentage'] = round(100 * $status['bytes_uploaded'] / $status['bytes_total']);
    }
  }
  elseif ($implementation == 'apc') {
    $status = apc_fetch('upload_' . $key);
    if (isset($status['current']) && !empty($status['total'])) {
      $progress['message'] = t('Uploading... (@current of @total)', array('@current' => format_size($status['current']), '@total' => format_size($status['total'])));
      $progress['percentage'] = round(100 * $status['current'] / $status['total']);
    }
  }

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  drupal_json_output($progress);
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}

/**
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 * Determines the preferred upload progress implementation.
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 *
 * @return
 *   A string indicating which upload progress system is available. Either "apc"
 *   or "uploadprogress". If neither are available, returns FALSE.
 */
function file_progress_implementation() {
  static $implementation;
  if (!isset($implementation)) {
    $implementation = FALSE;

    // We prefer the PECL extension uploadprogress because it supports multiple
    // simultaneous uploads. APC only supports one at a time.
    if (extension_loaded('uploadprogress')) {
      $implementation = 'uploadprogress';
    }
    elseif (extension_loaded('apc') && ini_get('apc.rfc1867')) {
      $implementation = 'apc';
    }
  }
  return $implementation;
}

/**
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 * Implements hook_file_predelete().
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 */
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function file_file_predelete($file) {
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  // TODO: Remove references to a file that is in-use.
}

/**
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 * Render API callback: Expands the managed_file element type.
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 *
 * Expands the file type to include Upload and Remove buttons, as well as
 * support for a default value.
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 *
 * This function is assigned as a #process callback in file_element_info().
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 */
function file_managed_file_process($element, &$form_state, $form) {
  $fid = isset($element['#value']['fid']) ? $element['#value']['fid'] : 0;

  // Set some default element properties.
  $element['#progress_indicator'] = empty($element['#progress_indicator']) ? 'none' : $element['#progress_indicator'];
  $element['#file'] = $fid ? file_load($fid) : FALSE;
  $element['#tree'] = TRUE;

  $ajax_settings = array(
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    'path' => 'file/ajax/' . implode('/', $element['#array_parents']) . '/' . $form['form_build_id']['#value'],
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    'wrapper' => $element['#id'] . '-ajax-wrapper',
    'effect' => 'fade',
    'progress' => array(
      'type' => $element['#progress_indicator'],
      'message' => $element['#progress_message'],
    ),
  );

  // Set up the buttons first since we need to check if they were clicked.
  $element['upload_button'] = array(
    '#name' => implode('_', $element['#parents']) . '_upload_button',
    '#type' => 'submit',
    '#value' => t('Upload'),
    '#validate' => array(),
    '#submit' => array('file_managed_file_submit'),
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    '#limit_validation_errors' => array($element['#parents']),
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    '#ajax' => $ajax_settings,
    '#weight' => -5,
  );

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  // Force the progress indicator for the remove button to be either 'none' or
  // 'throbber', even if the upload button is using something else.
  $ajax_settings['progress']['type'] = ($element['#progress_indicator'] == 'none') ? 'none' : 'throbber';
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  $ajax_settings['progress']['message'] = NULL;
  $ajax_settings['effect'] = 'none';
  $element['remove_button'] = array(
    '#name' => implode('_', $element['#parents']) . '_remove_button',
    '#type' => 'submit',
    '#value' => t('Remove'),
    '#validate' => array(),
    '#submit' => array('file_managed_file_submit'),
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    '#limit_validation_errors' => array($element['#parents']),
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    '#ajax' => $ajax_settings,
    '#weight' => -5,
  );

  $element['fid'] = array(
    '#type' => 'hidden',
    '#value' => $fid,
  );

  // Add progress bar support to the upload if possible.
  if ($element['#progress_indicator'] == 'bar' && $implementation = file_progress_implementation()) {
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    $upload_progress_key = mt_rand();
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    if ($implementation == 'uploadprogress') {
      $element['UPLOAD_IDENTIFIER'] = array(
        '#type' => 'hidden',
        '#value' => $upload_progress_key,
        '#attributes' => array('class' => array('file-progress')),
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        // Uploadprogress extension requires this field to be at the top of the
        // form.
        '#weight' => -20,
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      );
    }
    elseif ($implementation == 'apc') {
      $element['APC_UPLOAD_PROGRESS'] = array(
        '#type' => 'hidden',
        '#value' => $upload_progress_key,
        '#attributes' => array('class' => array('file-progress')),
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        // Uploadprogress extension requires this field to be at the top of the
        // form.
        '#weight' => -20,
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      );
    }

    // Add the upload progress callback.
    $element['upload_button']['#ajax']['progress']['path'] = 'file/progress/' . $upload_progress_key;
  }

  // The file upload field itself.
  $element['upload'] = array(
    '#name' => 'files[' . implode('_', $element['#parents']) . ']',
    '#type' => 'file',
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    '#title' => t('Choose a file'),
    '#title_display' => 'invisible',
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    '#size' => $element['#size'],
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    '#theme_wrappers' => array(),
    '#weight' => -10,
  );

  if ($fid && $element['#file']) {
    $element['filename'] = array(
      '#type' => 'markup',
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      '#markup' => theme('file_link', array('file' => $element['#file'])) . ' ',
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      '#weight' => -10,
    );
  }

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  // Add the extension list to the page as JavaScript settings.
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  if (isset($element['#upload_validators']['file_validate_extensions'][0])) {
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    $extension_list = implode(',', array_filter(explode(' ', $element['#upload_validators']['file_validate_extensions'][0])));
    $element['upload']['#attached']['js'] = array(
      array(
        'type' => 'setting',
        'data' => array('file' => array('elements' => array('#' . $element['#id'] . '-upload' => $extension_list)))
      )
    );
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  }

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  // Prefix and suffix used for Ajax replacement.
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  $element['#prefix'] = '<div id="' . $element['#id'] . '-ajax-wrapper">';
  $element['#suffix'] = '</div>';

  return $element;
}

/**
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 * Render API callback: Determines the value for a managed_file type element.
 *
 * This function is assigned as a #value_callback in file_element_info().
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 */
function file_managed_file_value(&$element, $input = FALSE, $form_state = NULL) {
  $fid = 0;

  // Find the current value of this field from the form state.
  $form_state_fid = $form_state['values'];
  foreach ($element['#parents'] as $parent) {
    $form_state_fid = isset($form_state_fid[$parent]) ? $form_state_fid[$parent] : 0;
  }

  if ($element['#extended'] && isset($form_state_fid['fid'])) {
    $fid = $form_state_fid['fid'];
  }
  elseif (is_numeric($form_state_fid)) {
    $fid = $form_state_fid;
  }

  // Process any input and save new uploads.
  if ($input !== FALSE) {
    $return = $input;

    // Uploads take priority over all other values.
    if ($file = file_managed_file_save_upload($element)) {
      $fid = $file->fid;
    }
    else {
      // Check for #filefield_value_callback values.
      // Because FAPI does not allow multiple #value_callback values like it
      // does for #element_validate and #process, this fills the missing
      // functionality to allow File fields to be extended through FAPI.
      if (isset($element['#file_value_callbacks'])) {
        foreach ($element['#file_value_callbacks'] as $callback) {
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          $callback($element, $input, $form_state);
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        }
      }
      // Load file if the FID has changed to confirm it exists.
      if (isset($input['fid']) && $file = file_load($input['fid'])) {
        $fid = $file->fid;
      }
    }
  }

  // If there is no input, set the default value.
  else {
    if ($element['#extended']) {
      $default_fid = isset($element['#default_value']['fid']) ? $element['#default_value']['fid'] : 0;
      $return = isset($element['#default_value']) ? $element['#default_value'] : array('fid' => 0);
    }
    else {
      $default_fid = isset($element['#default_value']) ? $element['#default_value'] : 0;
      $return = array('fid' => 0);
    }

    // Confirm that the file exists when used as a default value.
    if ($default_fid && $file = file_load($default_fid)) {
      $fid = $file->fid;
    }
  }

  $return['fid'] = $fid;

  return $return;
}

/**
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 * Render API callback: Validates the managed_file element.
 *
 * This function is assigned as a #element_validate callback in
 * file_element_info().
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 */
function file_managed_file_validate(&$element, &$form_state) {
  // If referencing an existing file, only allow if there are existing
  // references. This prevents unmanaged files from being deleted if this
  // item were to be deleted.
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  $clicked_button = end($form_state['triggering_element']['#parents']);
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  if ($clicked_button != 'remove_button' && !empty($element['fid']['#value'])) {
    if ($file = file_load($element['fid']['#value'])) {
      if ($file->status == FILE_STATUS_PERMANENT) {
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        $references = file_usage_list($file);
        if (empty($references)) {
          form_error($element, t('The file used in the !name field may not be referenced.', array('!name' => $element['#title'])));
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        }
      }
    }
    else {
      form_error($element, t('The file referenced by the !name field does not exist.', array('!name' => $element['#title'])));
    }
  }

  // Check required property based on the FID.
  if ($element['#required'] && empty($element['fid']['#value']) && !in_array($clicked_button, array('upload_button', 'remove_button'))) {
    form_error($element['upload'], t('!name field is required.', array('!name' => $element['#title'])));
  }

  // Consolidate the array value of this field to a single FID.
  if (!$element['#extended']) {
    form_set_value($element, $element['fid']['#value'], $form_state);
  }
}

/**
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 * Form submission handler for upload / remove buttons of managed_file elements.
 *
 * @see file_managed_file_process()
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 */
function file_managed_file_submit($form, &$form_state) {
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  // Determine whether it was the upload or the remove button that was clicked,
  // and set $element to the managed_file element that contains that button.
  $parents = $form_state['triggering_element']['#array_parents'];
  $button_key = array_pop($parents);
593
  $element = drupal_array_get_nested_value($form, $parents);
594 595 596 597 598 599 600

  // No action is needed here for the upload button, because all file uploads on
  // the form are processed by file_managed_file_value() regardless of which
  // button was clicked. Action is needed here for the remove button, because we
  // only remove a file in response to its remove button being clicked.
  if ($button_key == 'remove_button') {
    // If it's a temporary file we can safely remove it immediately, otherwise
601 602
    // it's up to the implementing module to remove usages of files to have them
    // removed.
603 604 605 606 607 608 609 610 611
    if ($element['#file'] && $element['#file']->status == 0) {
      file_delete($element['#file']);
    }
    // Update both $form_state['values'] and $form_state['input'] to reflect
    // that the file has been removed, so that the form is rebuilt correctly.
    // $form_state['values'] must be updated in case additional submit handlers
    // run, and for form building functions that run during the rebuild, such as
    // when the managed_file element is part of a field widget.
    // $form_state['input'] must be updated so that file_managed_file_value()
612
    // has correct information during the rebuild.
613 614
    $values_element = $element['#extended'] ? $element['fid'] : $element;
    form_set_value($values_element, NULL, $form_state);
615
    drupal_array_set_nested_value($form_state['input'], $values_element['#parents'], NULL);
616 617 618 619 620 621 622 623 624
  }

  // Set the form to rebuild so that $form is correctly updated in response to
  // processing the file removal. Since this function did not change $form_state
  // if the upload button was clicked, a rebuild isn't necessary in that
  // situation and setting $form_state['redirect'] to FALSE would suffice.
  // However, we choose to always rebuild, to keep the form processing workflow
  // consistent between the two buttons.
  $form_state['rebuild'] = TRUE;
625 626 627
}

/**
628
 * Saves any files that have been uploaded into a managed_file element.
629 630 631
 *
 * @param $element
 *   The FAPI element whose values are being saved.
632
 *
633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659
 * @return
 *   The file object representing the file that was saved, or FALSE if no file
 *   was saved.
 */
function file_managed_file_save_upload($element) {
  $upload_name = implode('_', $element['#parents']);
  if (empty($_FILES['files']['name'][$upload_name])) {
    return FALSE;
  }

  $destination = isset($element['#upload_location']) ? $element['#upload_location'] : NULL;
  if (isset($destination) && !file_prepare_directory($destination, FILE_CREATE_DIRECTORY)) {
    watchdog('file', 'The upload directory %directory for the file field !name could not be created or is not accessible. A newly uploaded file could not be saved in this directory as a consequence, and the upload was canceled.', array('%directory' => $destination, '!name' => $element['#field_name']));
    form_set_error($upload_name, t('The file could not be uploaded.'));
    return FALSE;
  }

  if (!$file = file_save_upload($upload_name, $element['#upload_validators'], $destination)) {
    watchdog('file', 'The file upload failed. %upload', array('%upload' => $upload_name));
    form_set_error($upload_name, t('The file in the !name field was unable to be uploaded.', array('!name' => $element['#title'])));
    return FALSE;
  }

  return $file;
}

/**
660 661 662 663 664 665 666
 * Returns HTML for a managed file element.
 *
 * @param $variables
 *   An associative array containing:
 *   - element: A render element representing the file.
 *
 * @ingroup themeable
667
 */
668 669 670
function theme_file_managed_file($variables) {
  $element = $variables['element'];

671 672 673 674 675 676 677 678 679
  $attributes = array();
  if (isset($element['#id'])) {
    $attributes['id'] = $element['#id'];
  }
  if (!empty($element['#attributes']['class'])) {
    $attributes['class'] = (array) $element['#attributes']['class'];
  }
  $attributes['class'][] = 'form-managed-file';

680 681
  // This wrapper is required to apply JS behaviors and CSS styling.
  $output = '';
682
  $output .= '<div' . drupal_attributes($attributes) . '>';
683 684 685 686 687
  $output .= drupal_render_children($element);
  $output .= '</div>';
  return $output;
}

688
/**
689
 * Render API callback: Hides display of the upload or remove controls.
690 691 692 693 694 695 696 697 698 699 700 701 702 703
 *
 * Upload controls are hidden when a file is already uploaded. Remove controls
 * are hidden when there is no file attached. Controls are hidden here instead
 * of in file_managed_file_process(), because #access for these buttons depends
 * on the managed_file element's #value. See the documentation of form_builder()
 * for more detailed information about the relationship between #process,
 * #value, and #access.
 *
 * Because #access is set here, it affects display only and does not prevent
 * JavaScript or other untrusted code from submitting the form as though access
 * were enabled. The form processing functions for these elements should not
 * assume that the buttons can't be "clicked" just because they are not
 * displayed.
 *
704 705
 * This function is assigned as a #pre_render callback in file_element_info().
 *
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 * @see file_managed_file_process()
 * @see form_builder()
 */
function file_managed_file_pre_render($element) {
  // If we already have a file, we don't want to show the upload controls.
  if (!empty($element['#value']['fid'])) {
    $element['upload']['#access'] = FALSE;
    $element['upload_button']['#access'] = FALSE;
  }
  // If we don't already have a file, there is nothing to remove.
  else {
    $element['remove_button']['#access'] = FALSE;
  }
  return $element;
}

722
/**
723
 * Returns HTML for a link to a file.
724
 *
725 726 727
 * @param $variables
 *   An associative array containing:
 *   - file: A file object to which the link will be created.
728 729
 *   - icon_directory: (optional) A path to a directory of icons to be used for
 *     files. Defaults to the value of the "file_icon_directory" variable.
730 731
 *
 * @ingroup themeable
732
 */
733 734
function theme_file_link($variables) {
  $file = $variables['file'];
735
  $icon_directory = $variables['icon_directory'];
736

737
  $url = file_create_url($file->uri);
738
  $icon = theme('file_icon', array('file' => $file, 'icon_directory' => $icon_directory));
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  // Set options as per anchor format described at
  // http://microformats.org/wiki/file-format-examples
  $options = array(
    'attributes' => array(
      'type' => $file->filemime . '; length=' . $file->filesize,
    ),
  );

  // Use the description as the link text if available.
749
  if (empty($file->description)) {
750
    $link_text = $file->filename;
751 752
  }
  else {
753
    $link_text = $file->description;
754 755 756 757 758 759 760
    $options['attributes']['title'] = check_plain($file->filename);
  }

  return '<span class="file">' . $icon . ' ' . l($link_text, $url, $options) . '</span>';
}

/**
761
 * Returns HTML for an image with an appropriate icon for the given file.
762
 *
763 764 765
 * @param $variables
 *   An associative array containing:
 *   - file: A file object for which to make an icon.
766 767
 *   - icon_directory: (optional) A path to a directory of icons to be used for
 *     files. Defaults to the value of the "file_icon_directory" variable.
768 769
 *
 * @ingroup themeable
770
 */
771 772
function theme_file_icon($variables) {
  $file = $variables['file'];
773
  $icon_directory = $variables['icon_directory'];
774

775
  $mime = check_plain($file->filemime);
776
  $icon_url = file_icon_url($file, $icon_directory);
777 778 779 780
  return '<img class="file-icon" alt="" title="' . $mime . '" src="' . $icon_url . '" />';
}

/**
781
 * Creates a URL to the icon for a file object.
782 783 784 785 786 787
 *
 * @param $file
 *   A file object.
 * @param $icon_directory
 *   (optional) A path to a directory of icons to be used for files. Defaults to
 *   the value of the "file_icon_directory" variable.
788
 *
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 * @return
 *   A URL string to the icon, or FALSE if an appropriate icon cannot be found.
 */
function file_icon_url($file, $icon_directory = NULL) {
  if ($icon_path = file_icon_path($file, $icon_directory)) {
    return base_path() . $icon_path;
  }
  return FALSE;
}

/**
800
 * Creates a path to the icon for a file object.
801 802 803 804 805 806
 *
 * @param $file
 *   A file object.
 * @param $icon_directory
 *   (optional) A path to a directory of icons to be used for files. Defaults to
 *   the value of the "file_icon_directory" variable.
807
 *
808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852
 * @return
 *   A string to the icon as a local path, or FALSE if an appropriate icon could
 *   not be found.
 */
function file_icon_path($file, $icon_directory = NULL) {
  // Use the default set of icons if none specified.
  if (!isset($icon_directory)) {
    $icon_directory = variable_get('file_icon_directory', drupal_get_path('module', 'file') . '/icons');
  }

  // If there's an icon matching the exact mimetype, go for it.
  $dashed_mime = strtr($file->filemime, array('/' => '-'));
  $icon_path = $icon_directory . '/' . $dashed_mime . '.png';
  if (file_exists($icon_path)) {
    return $icon_path;
  }

  // For a few mimetypes, we can "manually" map to a generic icon.
  $generic_mime = (string) file_icon_map($file);
  $icon_path = $icon_directory . '/' . $generic_mime . '.png';
  if ($generic_mime && file_exists($icon_path)) {
    return $icon_path;
  }

  // Use generic icons for each category that provides such icons.
  foreach (array('audio', 'image', 'text', 'video') as $category) {
    if (strpos($file->filemime, $category . '/') === 0) {
      $icon_path = $icon_directory . '/' . $category . '-x-generic.png';
      if (file_exists($icon_path)) {
        return $icon_path;
      }
    }
  }

  // Try application-octet-stream as last fallback.
  $icon_path = $icon_directory . '/application-octet-stream.png';
  if (file_exists($icon_path)) {
    return $icon_path;
  }

  // No icon can be found.
  return FALSE;
}

/**
853
 * Determines the generic icon MIME package based on a file's MIME type.
854 855 856
 *
 * @param $file
 *   A file object.
857
 *
858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984
 * @return
 *   The generic icon MIME package expected for this file.
 */
function file_icon_map($file) {
  switch ($file->filemime) {
    // Word document types.
    case 'application/msword':
    case 'application/vnd.ms-word.document.macroEnabled.12':
    case 'application/vnd.oasis.opendocument.text':
    case 'application/vnd.oasis.opendocument.text-template':
    case 'application/vnd.oasis.opendocument.text-master':
    case 'application/vnd.oasis.opendocument.text-web':
    case 'application/vnd.openxmlformats-officedocument.wordprocessingml.document':
    case 'application/vnd.stardivision.writer':
    case 'application/vnd.sun.xml.writer':
    case 'application/vnd.sun.xml.writer.template':
    case 'application/vnd.sun.xml.writer.global':
    case 'application/vnd.wordperfect':
    case 'application/x-abiword':
    case 'application/x-applix-word':
    case 'application/x-kword':
    case 'application/x-kword-crypt':
      return 'x-office-document';

    // Spreadsheet document types.
    case 'application/vnd.ms-excel':
    case 'application/vnd.ms-excel.sheet.macroEnabled.12':
    case 'application/vnd.oasis.opendocument.spreadsheet':
    case 'application/vnd.oasis.opendocument.spreadsheet-template':
    case 'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet':
    case 'application/vnd.stardivision.calc':
    case 'application/vnd.sun.xml.calc':
    case 'application/vnd.sun.xml.calc.template':
    case 'application/vnd.lotus-1-2-3':
    case 'application/x-applix-spreadsheet':
    case 'application/x-gnumeric':
    case 'application/x-kspread':
    case 'application/x-kspread-crypt':
      return 'x-office-spreadsheet';

    // Presentation document types.
    case 'application/vnd.ms-powerpoint':
    case 'application/vnd.ms-powerpoint.presentation.macroEnabled.12':
    case 'application/vnd.oasis.opendocument.presentation':
    case 'application/vnd.oasis.opendocument.presentation-template':
    case 'application/vnd.openxmlformats-officedocument.presentationml.presentation':
    case 'application/vnd.stardivision.impress':
    case 'application/vnd.sun.xml.impress':
    case 'application/vnd.sun.xml.impress.template':
    case 'application/x-kpresenter':
      return 'x-office-presentation';

    // Compressed archive types.
    case 'application/zip':
    case 'application/x-zip':
    case 'application/stuffit':
    case 'application/x-stuffit':
    case 'application/x-7z-compressed':
    case 'application/x-ace':
    case 'application/x-arj':
    case 'application/x-bzip':
    case 'application/x-bzip-compressed-tar':
    case 'application/x-compress':
    case 'application/x-compressed-tar':
    case 'application/x-cpio-compressed':
    case 'application/x-deb':
    case 'application/x-gzip':
    case 'application/x-java-archive':
    case 'application/x-lha':
    case 'application/x-lhz':
    case 'application/x-lzop':
    case 'application/x-rar':
    case 'application/x-rpm':
    case 'application/x-tzo':
    case 'application/x-tar':
    case 'application/x-tarz':
    case 'application/x-tgz':
      return 'package-x-generic';

    // Script file types.
    case 'application/ecmascript':
    case 'application/javascript':
    case 'application/mathematica':
    case 'application/vnd.mozilla.xul+xml':
    case 'application/x-asp':
    case 'application/x-awk':
    case 'application/x-cgi':
    case 'application/x-csh':
    case 'application/x-m4':
    case 'application/x-perl':
    case 'application/x-php':
    case 'application/x-ruby':
    case 'application/x-shellscript':
    case 'text/vnd.wap.wmlscript':
    case 'text/x-emacs-lisp':
    case 'text/x-haskell':
    case 'text/x-literate-haskell':
    case 'text/x-lua':
    case 'text/x-makefile':
    case 'text/x-matlab':
    case 'text/x-python':
    case 'text/x-sql':
    case 'text/x-tcl':
      return 'text-x-script';

    // HTML aliases.
    case 'application/xhtml+xml':
      return 'text-html';

    // Executable types.
    case 'application/x-macbinary':
    case 'application/x-ms-dos-executable':
    case 'application/x-pef-executable':
      return 'application-x-executable';

    default:
      return FALSE;
  }
}

/**
 * @defgroup file-module-api File module public API functions
 * @{
 * These functions may be used to determine if and where a file is in use.
 */

/**
985
 * Retrieves a list of references to a file.
986 987 988 989
 *
 * @param $file
 *   A file object.
 * @param $field
990 991
 *   (optional) A field array to be used for this check. If given, limits the
 *   reference check to the given field.
992 993 994 995
 * @param $age
 *   (optional) A constant that specifies which references to count. Use
 *   FIELD_LOAD_REVISION to retrieve all references within all revisions or
 *   FIELD_LOAD_CURRENT to retrieve references only in the current revisions.
996
 * @param $field_type
997 998 999
 *   (optional) The name of a field type. If given, limits the reference check
 *   to fields of the given type.
 *
1000 1001 1002
 * @return
 *   An integer value.
 */
1003
function file_get_file_references($file, $field = NULL, $age = FIELD_LOAD_REVISION, $field_type = 'file') {
1004
  $references = drupal_static(__FUNCTION__, array());
1005
  $fields = isset($field) ? array($field['field_name'] => $field) : field_info_fields();
1006 1007

  foreach ($fields as $field_name => $file_field) {
1008
    if ((empty($field_type) || $file_field['type'] == $field_type) && !isset($references[$field_name])) {
1009
      // Get each time this file is used within a field.
1010
      $query = new EntityFieldQuery();
1011 1012 1013 1014
      $query
        ->fieldCondition($file_field, 'fid', $file->fid)
        ->age($age);
      $references[$field_name] = $query->execute();
1015 1016 1017
    }
  }

1018
  return isset($field) ? $references[$field['field_name']] : array_filter($references);
1019 1020 1021 1022 1023
}

/**
 * @} End of "defgroup file-module-api".
 */