filefield_sources.module in FileField Sources 7
Same filename and directory in other branches
Extend FileField to allow files from multiple sources.
File
filefield_sources.moduleView source
<?php
/**
* @file
* Extend FileField to allow files from multiple sources.
*/
/**
* Implements hook_menu().
*/
function filefield_sources_menu() {
$params = array();
return filefield_sources_invoke_all('menu', $params);
}
/**
* Implements hook_element_info().
*/
function filefield_sources_element_info() {
$elements = array();
$elements['managed_file']['#process'] = array(
'filefield_sources_field_process',
);
$elements['managed_file']['#pre_render'] = array(
'filefield_sources_field_pre_render',
);
$elements['managed_file']['#element_validate'] = array(
'filefield_sources_field_validate',
);
$elements['managed_file']['#file_value_callbacks'] = array(
'filefield_sources_field_value',
);
return $elements;
}
/**
* Implements hook_theme().
*/
function filefield_sources_theme() {
$params = array();
$theme = filefield_sources_invoke_all('theme', $params);
$theme['filefield_sources_list'] = array(
'arguments' => array(
'sources' => NULL,
),
);
return $theme;
}
/**
* Implements hook_filefield_sources_widgets().
*
* This returns a list of widgets that are compatible with FileField Sources.
*/
function filefield_sources_filefield_sources_widgets() {
return array(
'file_generic',
'image_image',
);
}
/**
* Implements hook_form_FORM_ID_alter().
*/
function filefield_sources_form_field_ui_field_edit_form_alter(&$form, &$form_state) {
$instance = $form['#instance'];
if (in_array($instance['widget']['type'], module_invoke_all('filefield_sources_widgets'))) {
if (!empty($form['instance']['widget']['settings'])) {
$form['instance']['widget']['settings'] += filefield_sources_form($instance, $form_state);
}
else {
$form['instance']['widget']['settings'] = filefield_sources_form($instance, $form_state);
}
}
}
/**
* A list of settings needed by FileField Sources module on widgets.
*/
function filefield_sources_field_widget_info_alter(&$info) {
$settings = array(
'filefield_sources' => array(),
);
foreach (module_invoke_all('filefield_sources_widgets') as $widget) {
$params = array(
'save',
$widget,
);
$widget_settings = array_merge($settings, filefield_sources_invoke_all('settings', $params));
if (isset($info[$widget])) {
$info[$widget]['settings']['filefield_sources'] = $widget_settings;
}
}
}
/**
* Configuration form for editing FileField Sources settings for a widget.
*/
function filefield_sources_form($instance, &$form_state) {
$settings = $instance['widget']['settings']['filefield_sources'];
// Backward compatibility: auto-enable 'upload'.
$enabled = _filefield_sources_enabled($settings);
$form['filefield_sources'] = array(
'#type' => 'fieldset',
'#title' => t('File sources'),
'#collapsible' => TRUE,
'#collapsed' => TRUE,
'#weight' => 20,
);
$sources = filefield_sources_list();
$form['filefield_sources']['filefield_sources'] = array(
'#type' => 'checkboxes',
'#title' => t('Enabled sources'),
'#options' => $sources,
'#default_value' => $enabled,
'#description' => t('Select the available locations from which this widget may select files.'),
);
// Make sure all includes are loaded for multistep forms.
$sources_info = filefield_sources_info(FALSE);
foreach ($sources_info as $source_name => $source) {
if (isset($source['file'])) {
_filefield_sources_form_include($source['module'], $source['file'], $form_state);
}
}
$params = array(
'form',
$instance,
);
$form['filefield_sources'] = array_merge($form['filefield_sources'], filefield_sources_invoke_all('settings', $params));
return $form;
}
/**
* A #process callback to extend the filefield_widget element type.
*
* Add the central JavaScript and CSS files that allow switching between
* different sources. Third-party modules can also add to the list of sources
* by implementing hook_filefield_sources_info().
*/
function filefield_sources_field_process($element, &$form_state, $form) {
static $js_added;
// If not a recognized field instance, do not process.
if (!isset($element['#field_name']) || !($instance = field_widget_instance($element, $form_state)) || !isset($instance['widget']['settings']['filefield_sources']['filefield_sources'])) {
return $element;
}
// Do all processing as needed by each source.
$sources = filefield_sources_info();
$enabled_sources = _filefield_sources_enabled($instance['widget']['settings']['filefield_sources']);
$context = array(
'enabled_sources' => &$enabled_sources,
'element' => $element,
'form_state' => $form_state,
);
// Allow other modules to alter the sources.
drupal_alter('filefield_sources_sources', $sources, $context);
foreach ($sources as $source_name => $source) {
if (empty($enabled_sources[$source_name])) {
unset($sources[$source_name]);
}
else {
if (isset($source['process'])) {
$function = $source['process'];
$element = $function($element, $form_state, $form);
}
if (isset($source['file'])) {
_filefield_sources_form_include($source['module'], $source['file'], $form_state);
}
}
}
$element['#filefield_sources'] = $sources;
// Exit out if not adding any sources.
if (empty($sources)) {
return $element;
}
// Hide default 'upload' type?
if (!isset($enabled_sources['upload'])) {
foreach (array(
'upload_button',
'upload',
) as $field) {
if (isset($element[$field])) {
$element[$field]['#access'] = FALSE;
}
}
}
// Add basic JS and CSS.
$path = drupal_get_path('module', 'filefield_sources');
$element['#attached']['css'][] = $path . '/filefield_sources.css';
$element['#attached']['js'][] = $path . '/filefield_sources.js';
// Check the element for hint text that might need to be added.
foreach (element_children($element) as $key) {
if (isset($element[$key]['#filefield_sources_hint_text']) && !isset($js_added[$key])) {
$type = str_replace('filefield_', '', $key);
drupal_add_js(array(
'fileFieldSources' => array(
$type => array(
'hintText' => $element[$key]['#filefield_sources_hint_text'],
),
),
), 'setting');
$js_added[$key] = TRUE;
}
}
// Adjust the AJAX settings so that on upload and remove of any individual
// file, the entire group of file fields is updated together.
// Copied directly from file_field_widget_process().
$field = field_widget_field($element, $form_state);
if ($field['cardinality'] != 1) {
$parents = array_slice($element['#array_parents'], 0, -1);
$new_path = 'file/ajax/' . implode('/', $parents) . '/' . $form['form_build_id']['#value'];
$field_element = drupal_array_get_nested_value($form, $parents);
$new_wrapper = $field_element['#id'] . '-ajax-wrapper';
foreach (element_children($element) as $key) {
foreach (element_children($element[$key]) as $subkey) {
if (isset($element[$key][$subkey]['#ajax'])) {
$element[$key][$subkey]['#ajax']['path'] = $new_path;
$element[$key][$subkey]['#ajax']['wrapper'] = $new_wrapper;
$element[$key][$subkey]['#limit_validation_errors'] = array(
$parents,
);
}
}
}
}
// Add the list of sources to the element for toggling between sources.
if (empty($element['fid']['#value'])) {
if (count($enabled_sources) > 1) {
$element['filefield_sources_list'] = array(
'#type' => 'markup',
'#markup' => theme('filefield_sources_list', array(
'element' => $element,
'sources' => $sources,
)),
'#weight' => -20,
);
}
}
return $element;
}
/**
* A #pre_render function to hide sources if a file is currently uploaded.
*/
function filefield_sources_field_pre_render($element) {
// If we already have a file, we don't want to show the upload controls.
if (!empty($element['#value']['fid'])) {
foreach (element_children($element) as $key) {
if (!empty($element[$key]['#filefield_source'])) {
$element[$key]['#access'] = FALSE;
}
}
}
return $element;
}
/**
* An #element_validate function to run source validations.
*/
function filefield_sources_field_validate($element, &$form_state, $form) {
// Do all processing as needed by each source.
$sources = filefield_sources_info();
foreach ($sources as $source) {
if (isset($source['validate'])) {
$function = $source['validate'];
$function($element, $form_state, $form);
}
}
}
/**
* A #submit handler added to all FileField Source buttons.
*/
function filefield_sources_field_submit(&$form, &$form_state) {
$parents = array_slice($form_state['triggering_element']['#array_parents'], 0, -3);
$element = drupal_array_get_nested_value($form, $parents);
$field_name = $element['#field_name'];
$langcode = $element['#language'];
// Get exisitng file values.
// File Field items are stored in the field state after ajax reloads starting
// from Drupal 7.8. We try to support all releases by merging the items.
$field_state = field_form_get_state($element['#field_parents'], $field_name, $langcode, $form_state);
$field_values = drupal_array_get_nested_value($form_state['values'], $parents);
if (isset($field_values) && isset($field_state['items'])) {
$field_values += $field_state['items'];
}
elseif (isset($field_state['items'])) {
$field_values = $field_state['items'];
}
if (isset($field_values)) {
// Update sort order according to weight. Note that this is always stored in
// form state. Sort does not work using regular upload, but that is a core
// bug.
usort($field_values, '_field_sort_items_helper');
// Update form_state values.
drupal_array_set_nested_value($form_state['values'], $parents, $field_values);
// Update items.
$field_state['items'] = $field_values;
field_form_set_state($element['#field_parents'], $field_name, $langcode, $form_state, $field_state);
}
// Clear out input as it will need to be rebuildt.
drupal_array_set_nested_value($form_state['input'], $element['#parents'], NULL);
$form_state['rebuild'] = TRUE;
}
/**
* A #filefield_value_callback to run source value callbacks.
*/
function filefield_sources_field_value($element, &$item, &$form_state) {
// Do all processing as needed by each source.
$sources = filefield_sources_info();
foreach ($sources as $source) {
if (isset($source['value'])) {
$function = $source['value'];
$function($element, $item);
}
}
}
/**
* Call all FileField Source hooks stored in the available include files.
*/
function filefield_sources_invoke_all($method, &$params) {
$return = array();
foreach (filefield_sources_includes() as $source) {
$function = 'filefield_source_' . $source . '_' . $method;
if (function_exists($function)) {
$result = call_user_func_array($function, $params);
if (isset($result) && is_array($result)) {
$return = array_merge_recursive($return, $result);
}
elseif (isset($result)) {
$return[] = $result;
}
}
}
return $return;
}
/**
* Load hook_filefield_sources_info() data from all modules.
*/
function filefield_sources_info($include_default = TRUE) {
// Cache the expensive part.
$cache =& drupal_static(__FUNCTION__, array());
if (empty($cache)) {
$cache['upload'] = array(
'name' => t('Upload (default)'),
'label' => t('Upload'),
'description' => t('Upload a file from your computer.'),
'weight' => -10,
);
// Add the providing module name to each source.
foreach (module_implements('filefield_sources_info') as $module) {
$function = $module . '_filefield_sources_info';
$additions = $function();
foreach ($additions as $source_name => $source_info) {
$additions[$source_name]['module'] = $module;
}
$cache += $additions;
}
drupal_alter('filefield_sources_info', $cache);
uasort($cache, '_filefield_sources_sort');
}
// Remove the upload option from the returned value if needed.
$info = $cache;
if (!$include_default) {
unset($info['upload']);
}
return $info;
}
/**
* Create a list of FileField Sources by name, suitable for a select list.
*/
function filefield_sources_list($include_default = TRUE) {
$info = filefield_sources_info($include_default);
$list = array();
foreach ($info as $key => $source) {
$list[$key] = $source['name'];
}
return $list;
}
/**
* Implements hook_filefield_sources_info().
*/
function filefield_sources_filefield_sources_info() {
$params = array();
return filefield_sources_invoke_all('info', $params);
}
/**
* Load all the potential sources.
*/
function filefield_sources_includes($include = TRUE, $enabled_only = TRUE) {
if ($enabled_only) {
$enabled_includes = variable_get('filefield_sources', filefield_sources_includes(FALSE, FALSE));
}
$includes = array();
$directory = drupal_get_path('module', 'filefield_sources') . '/sources';
foreach (file_scan_directory($directory, '/\\.inc$/') as $file) {
if (!$enabled_only || in_array($file->name, $enabled_includes)) {
$includes[] = $file->name;
if ($include) {
include_once DRUPAL_ROOT . '/' . $file->uri;
}
}
}
return $includes;
}
/**
* Check the current user's access to a file through hook_file_download().
*
* @param $uri
* A file URI as loaded from the database.
* @return
* Boolean TRUE if the user has access, FALSE otherwise.
*
* @see file_download()
* @see hook_file_download().
*/
function filefield_sources_file_access($uri) {
// Always allow access to public files.
$scheme = file_uri_scheme($uri);
if ($scheme === 'public') {
return TRUE;
}
// Or if the current user has the "bypass file access" permission from the
// File Entity module, then reuse of any file is permitted.
if (user_access('bypass file access')) {
return TRUE;
}
$headers = array();
foreach (module_implements('file_download') as $module) {
$function = $module . '_file_download';
$result = $function($uri);
if ($result == -1) {
// Throw away the headers received so far.
$headers = array();
break;
}
if (isset($result) && is_array($result)) {
$headers = array_merge($headers, $result);
}
}
return !empty($headers);
}
/**
* Save a file into the database after validating it.
*
* This function is identical to the core function file_save_upload() except
* that it accepts an input file path instead of an input file source name.
*
* @see file_save_upload().
*/
function filefield_sources_save_file($filepath, $validators = array(), $destination = FALSE, $replace = FILE_EXISTS_RENAME) {
global $user;
// Begin building file object.
$file = new stdClass();
$file->uid = $user->uid;
$file->status = 0;
$file->filename = trim(basename($filepath), '.');
$file->uri = $filepath;
$file->filemime = file_get_mimetype($file->filename);
$file->filesize = filesize($filepath);
$extensions = '';
if (isset($validators['file_validate_extensions'])) {
if (isset($validators['file_validate_extensions'][0])) {
// Build the list of non-munged extensions if the caller provided them.
$extensions = $validators['file_validate_extensions'][0];
}
else {
// If 'file_validate_extensions' is set and the list is empty then the
// caller wants to allow any extension. In this case we have to remove the
// validator or else it will reject all extensions.
unset($validators['file_validate_extensions']);
}
}
else {
// No validator was provided, so add one using the default list.
// Build a default non-munged safe list for file_munge_filename().
$extensions = 'jpg jpeg gif png txt doc xls pdf ppt pps odt ods odp';
$validators['file_validate_extensions'] = array();
$validators['file_validate_extensions'][0] = $extensions;
}
if (!empty($extensions)) {
// Munge the filename to protect against possible malicious extension hiding
// within an unknown file type (ie: filename.html.foo).
$file->filename = file_munge_filename($file->filename, $extensions);
}
// Rename potentially executable files, to help prevent exploits (i.e. will
// rename filename.php.foo and filename.php to filename.php.foo.txt and
// filename.php.txt, respectively). Don't rename if 'allow_insecure_uploads'
// evaluates to TRUE.
if (!variable_get('allow_insecure_uploads', 0) && preg_match('/\\.(php|pl|py|cgi|asp|js)(\\.|$)/i', $file->filename) && substr($file->filename, -4) != '.txt') {
$file->filemime = 'text/plain';
$file->uri .= '.txt';
$file->filename .= '.txt';
// The .txt extension may not be in the allowed list of extensions. We have
// to add it here or else the file upload will fail.
if (!empty($extensions)) {
$validators['file_validate_extensions'][0] .= ' txt';
drupal_set_message(t('For security reasons, your upload has been renamed to %filename.', array(
'%filename' => $file->filename,
)));
}
}
// If the destination is not provided, use the temporary directory.
if (empty($destination)) {
$destination = 'temporary://';
}
// Assert that the destination contains a valid stream.
$destination_scheme = file_uri_scheme($destination);
if (!$destination_scheme || !file_stream_wrapper_valid_scheme($destination_scheme)) {
drupal_set_message(t('The file could not be uploaded, because the destination %destination is invalid.', array(
'%destination' => $destination,
)), 'error');
return FALSE;
}
// A URI may already have a trailing slash or look like "public://".
if (substr($destination, -1) != '/') {
$destination .= '/';
}
// Ensure the destination is writable.
file_prepare_directory($destination, FILE_CREATE_DIRECTORY);
// Check if this is actually the same file being "attached" to a file record.
// If so, it acts as a file replace, except no file is actually moved.
$reuse_file = $destination . $file->filename === $file->uri;
if ($reuse_file) {
$replace = FILE_EXISTS_REPLACE;
}
$file->destination = file_destination($destination . $file->filename, $replace);
// If file_destination() returns FALSE then $replace == FILE_EXISTS_ERROR and
// there's an existing file so we need to bail.
if ($file->destination === FALSE) {
drupal_set_message(t('The file %source could not be uploaded because a file by that name already exists in the destination %directory.', array(
'%source' => $file->filename,
'%directory' => $destination,
)), 'error');
return FALSE;
}
// Add in our check of the the file name length.
$validators['file_validate_name_length'] = array();
// Call the validation functions specified by this function's caller.
$errors = file_validate($file, $validators);
// Check for errors.
if (!empty($errors)) {
$message = t('The specified file %name could not be uploaded.', array(
'%name' => $file->filename,
));
if (count($errors) > 1) {
$message .= theme('item_list', array(
'items' => $errors,
));
}
else {
$message .= ' ' . array_pop($errors);
}
drupal_set_message($message, 'error');
return FALSE;
}
// Move uploaded files from PHP's upload_tmp_dir to Drupal's temporary
// directory. This overcomes open_basedir restrictions for future file
// operations.
$file->uri = $file->destination;
if (!$reuse_file && !file_unmanaged_copy($filepath, $file->uri, $replace)) {
drupal_set_message(t('File upload error. Could not move uploaded file.'), 'error');
watchdog('file', 'Upload error. Could not move uploaded file %file to destination %destination.', array(
'%file' => $file->filename,
'%destination' => $file->uri,
));
return FALSE;
}
// Set the permissions on the new file.
drupal_chmod($file->uri);
// If we are replacing an existing file re-use its database record.
if ($replace == FILE_EXISTS_REPLACE) {
$existing_files = file_load_multiple(array(), array(
'uri' => $file->uri,
));
if (count($existing_files)) {
$existing = reset($existing_files);
$file->fid = $existing->fid;
}
}
// If we made it this far it's safe to record this file in the database.
if ($file = file_save($file)) {
// Track non-public files in the session if they were uploaded by an
// anonymous user. This allows modules such as the File module to only
// grant view access to the specific anonymous user who uploaded the file.
// See similar code in file_save_upload().
if (!$user->uid && !in_array($destination_scheme, variable_get('file_public_schema', array(
'public',
)))) {
$_SESSION['anonymous_allowed_file_ids'][$file->fid] = $file->fid;
}
return $file;
}
return FALSE;
}
/**
* Clean up the file name, munging extensions and transliterating.
*
* @param $filepath
* A string containing a file name or full path. Only the file name will
* actually be modified.
* @return
* A file path with a cleaned-up file name.
*/
function filefield_sources_clean_filename($filepath, $extensions) {
global $user;
$filename = basename($filepath);
if (module_exists('transliteration')) {
module_load_include('inc', 'transliteration');
$langcode = NULL;
if (!empty($_POST['language'])) {
$languages = language_list();
$langcode = isset($languages[$_POST['language']]) ? $_POST['language'] : NULL;
}
$filename = transliteration_clean_filename($filename, $langcode);
}
// Because this transfer mechanism does not use file_save_upload(), we need
// to manually munge the filename to prevent dangerous extensions.
// See file_save_upload().
if (empty($extensions)) {
$extensions = 'jpg jpeg gif png txt doc xls pdf ppt pps odt ods odp';
}
$filename = file_munge_filename($filename, $extensions);
$directory = drupal_dirname($filepath);
return ($directory != '.' ? $directory . '/' : '') . $filename;
}
/**
* Theme the display of the sources list.
*/
function theme_filefield_sources_list($variables) {
$element = $variables['element'];
$sources = $variables['sources'];
$links = array();
foreach ($sources as $name => $source) {
$links[] = '<a href="#" onclick="return false;" title="' . $source['description'] . '" id="' . $element['#id'] . '-' . $name . '-source" class="filefield-source filefield-source-' . $name . '">' . $source['label'] . '</a>';
}
return '<div class="filefield-sources-list">' . implode(' | ', $links) . '</div>';
}
/**
* Validate a file based on the $element['#upload_validators'] property.
*/
function filefield_sources_element_validate($element, $file) {
$validators = $element['#upload_validators'];
$errors = array();
// Since this frequently is used to reference existing files, check that
// they exist first in addition to the normal validations.
if (!file_exists($file->uri)) {
$errors[] = t('The file does not exist.');
}
else {
foreach ($validators as $function => $args) {
// Add the $file variable to the list of arguments and pass it by
// reference (required for PHP 5.3 and higher).
array_unshift($args, NULL);
$args[0] =& $file;
$errors = array_merge($errors, call_user_func_array($function, $args));
}
}
// Check for validation errors.
if (!empty($errors)) {
$message = t('The selected file %name could not be referenced.', array(
'%name' => $file->filename,
));
if (count($errors) > 1) {
$message .= '<ul><li>' . implode('</li><li>', $errors) . '</li></ul>';
}
else {
$message .= ' ' . array_pop($errors);
}
form_error($element, $message);
return 0;
}
return 1;
}
/**
* Generate help text based on the $element['#upload_validators'] property.
*/
function filefield_sources_element_validation_help($validators) {
$desc = array();
foreach ($validators as $callback => $arguments) {
$help_func = $callback . '_help';
if (function_exists($help_func)) {
$desc[] = call_user_func_array($help_func, $arguments);
}
}
return empty($desc) ? '' : implode('<br />', $desc);
}
/**
* Menu access callback; Checks user access to edit a file field.
*/
function _filefield_sources_field_access($entity_type, $bundle_name, $field_name) {
$field = field_info_field($field_name);
return field_access('edit', $field, $entity_type);
}
/**
* Custom sort function for ordering sources.
*/
function _filefield_sources_sort($a, $b) {
$a = (array) $a + array(
'weight' => 0,
'label' => '',
);
$b = (array) $b + array(
'weight' => 0,
'label' => '',
);
return $a['weight'] < $b['weight'] ? -1 : ($a['weight'] > $b['weight'] ? 1 : strnatcasecmp($a['label'], $b['label']));
}
/**
* Ensure that a source include file is loaded into $form_state.
*/
function _filefield_sources_form_include($module, $filepath, &$form_state) {
$last_dot = strrpos($filepath, '.');
$path = substr($filepath, 0, $last_dot);
$extension = substr($filepath, $last_dot + 1);
form_load_include($form_state, $extension, $module, $path);
}
/**
* Helper to return enabled sources for a field
*
* This provides backward compatibility for 'upload' type.
*
* @see http://drupal.org/node/932994
*/
function _filefield_sources_enabled($settings) {
if (!isset($settings['filefield_sources']['upload'])) {
$settings['filefield_sources']['upload'] = 'upload';
}
$enabled = array_keys(array_filter($settings['filefield_sources']));
return drupal_map_assoc($enabled);
}Functions
Name |
Description |
|---|---|
| filefield_sources_clean_filename | Clean up the file name, munging extensions and transliterating. |
| filefield_sources_element_info | Implements hook_element_info(). |
| filefield_sources_element_validate | Validate a file based on the $element['#upload_validators'] property. |
| filefield_sources_element_validation_help | Generate help text based on the $element['#upload_validators'] property. |
| filefield_sources_field_pre_render | A #pre_render function to hide sources if a file is currently uploaded. |
| filefield_sources_field_process | A #process callback to extend the filefield_widget element type. |
| filefield_sources_field_submit | A #submit handler added to all FileField Source buttons. |
| filefield_sources_field_validate | An #element_validate function to run source validations. |
| filefield_sources_field_value | A #filefield_value_callback to run source value callbacks. |
| filefield_sources_field_widget_info_alter | A list of settings needed by FileField Sources module on widgets. |
| filefield_sources_filefield_sources_info | Implements hook_filefield_sources_info(). |
| filefield_sources_filefield_sources_widgets | Implements hook_filefield_sources_widgets(). |
| filefield_sources_file_access | Check the current user's access to a file through hook_file_download(). |
| filefield_sources_form | Configuration form for editing FileField Sources settings for a widget. |
| filefield_sources_form_field_ui_field_edit_form_alter | Implements hook_form_FORM_ID_alter(). |
| filefield_sources_includes | Load all the potential sources. |
| filefield_sources_info | Load hook_filefield_sources_info() data from all modules. |
| filefield_sources_invoke_all | Call all FileField Source hooks stored in the available include files. |
| filefield_sources_list | Create a list of FileField Sources by name, suitable for a select list. |
| filefield_sources_menu | Implements hook_menu(). |
| filefield_sources_save_file | Save a file into the database after validating it. |
| filefield_sources_theme | Implements hook_theme(). |
| theme_filefield_sources_list | Theme the display of the sources list. |
| _filefield_sources_enabled | Helper to return enabled sources for a field |
| _filefield_sources_field_access | Menu access callback; Checks user access to edit a file field. |
| _filefield_sources_form_include | Ensure that a source include file is loaded into $form_state. |
| _filefield_sources_sort | Custom sort function for ordering sources. |