file.module

Same filename in other branches
  1. 7.x modules/file/file.module
  2. 9 core/modules/file/file.module
  3. 8.9.x core/modules/file/file.module
  4. 10 core/modules/file/file.module

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core/modules/file/file.module

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<?php


/**
 * @file
 */
use Drupal\Component\Utility\NestedArray;
use Drupal\Core\Entity\EntityStorageInterface;
use Drupal\Core\Field\FieldDefinitionInterface;
use Drupal\Core\Field\FieldFilteredMarkup;
use Drupal\Core\File\Exception\FileException;
use Drupal\Core\File\Exception\FileExistsException;
use Drupal\Core\File\Exception\FileWriteException;
use Drupal\Core\File\Exception\InvalidStreamWrapperException;
use Drupal\Core\File\FileExists;
use Drupal\Core\File\FileSystemInterface;
use Drupal\Core\Form\FormStateInterface;
use Drupal\Core\Link;
use Drupal\Core\Lock\LockAcquiringException;
use Drupal\Core\Messenger\MessengerInterface;
use Drupal\Core\Render\Element;
use Drupal\Core\StringTranslation\ByteSizeMarkup;
use Drupal\Core\Template\Attribute;
use Drupal\file\FileInterface;
use Drupal\file\IconMimeTypes;
use Drupal\file\Upload\FormUploadedFile;

/**
 * Examines a file entity and returns appropriate content headers for download.
 *
 * @param \Drupal\file\FileInterface $file
 *   A file entity.
 *
 * @return array
 *   An associative array of headers, as expected by
 *   \Symfony\Component\HttpFoundation\StreamedResponse.
 */
function file_get_content_headers(FileInterface $file) {
    return [
        'Content-Type' => $file->getMimeType(),
        'Content-Length' => $file->getSize(),
        'Cache-Control' => 'private',
    ];
}

/**
 * Saves form file uploads.
 *
 * The files will be added to the {file_managed} table as temporary files.
 * Temporary files are periodically cleaned. Use the 'file.usage' service to
 * register the usage of the file which will automatically mark it as permanent.
 *
 * @param array $element
 *   The FAPI element whose values are being saved.
 * @param \Drupal\Core\Form\FormStateInterface $form_state
 *   The current state of the form.
 * @param null|int $delta
 *   (optional) The delta of the file to return the file entity.
 *   Defaults to NULL.
 * @param \Drupal\Core\File\FileExists|int $fileExists
 *   (optional) The replace behavior when the destination file already exists.
 *
 * @return array|\Drupal\file\FileInterface|null|false
 *   An array of file entities or a single file entity if $delta != NULL. Each
 *   array element contains the file entity if the upload succeeded or FALSE if
 *   there was an error. Function returns NULL if no file was uploaded.
 *
 * @throws \ValueError
 *    Thrown if $fileExists is a legacy int and not a valid value.
 *
 * @internal
 *   This function is internal, and may be removed in a minor version release.
 *   It wraps file_save_upload() to allow correct error handling in forms.
 *   Contrib and custom code should not call this function, they should use the
 *   managed file upload widgets in core.
 *
 * @see https://www.drupal.org/project/drupal/issues/3069020
 * @see https://www.drupal.org/project/drupal/issues/2482783
 */
function _file_save_upload_from_form(array $element, FormStateInterface $form_state, $delta = NULL, FileExists|int $fileExists = FileExists::Rename) {
    if (!$fileExists instanceof FileExists) {
        // @phpstan-ignore staticMethod.deprecated
        $fileExists = FileExists::fromLegacyInt($fileExists, __METHOD__);
    }
    // Get all errors set before calling this method. This will also clear them
    // from the messenger service.
    $errors_before = \Drupal::messenger()->deleteByType(MessengerInterface::TYPE_ERROR);
    $upload_location = $element['#upload_location'] ?? FALSE;
    $upload_name = implode('_', $element['#parents']);
    $upload_validators = $element['#upload_validators'] ?? [];
    $result = file_save_upload($upload_name, $upload_validators, $upload_location, $delta, $fileExists);
    // Get new errors that are generated while trying to save the upload. This
    // will also clear them from the messenger service.
    $errors_new = \Drupal::messenger()->deleteByType(MessengerInterface::TYPE_ERROR);
    if (!empty($errors_new)) {
        if (count($errors_new) > 1) {
            // Render multiple errors into a single message.
            // This is needed because only one error per element is supported.
            $render_array = [
                'error' => [
                    '#markup' => t('One or more files could not be uploaded.'),
                ],
                'item_list' => [
                    '#theme' => 'item_list',
                    '#items' => $errors_new,
                ],
            ];
            $error_message = \Drupal::service('renderer')->renderInIsolation($render_array);
        }
        else {
            $error_message = reset($errors_new);
        }
        $form_state->setError($element, $error_message);
    }
    // Ensure that errors set prior to calling this method are still shown to the
    // user.
    if (!empty($errors_before)) {
        foreach ($errors_before as $error) {
            \Drupal::messenger()->addError($error);
        }
    }
    return $result;
}

/**
 * Saves file uploads to a new location.
 *
 * The files will be added to the {file_managed} table as temporary files.
 * Temporary files are periodically cleaned. Use the 'file.usage' service to
 * register the usage of the file which will automatically mark it as permanent.
 *
 * Note that this function does not support correct form error handling. The
 * file upload widgets in core do support this. It is advised to use these in
 * any custom form, instead of calling this function.
 *
 * @param string $form_field_name
 *   A string that is the associative array key of the upload form element in
 *   the form array.
 * @param array $validators
 *   (optional) An associative array of Validation Constraint plugins used to
 *   validate the file.
 *   If the array is empty, 'FileExtension' will be used by default with a safe
 *   list of extensions, as follows: "jpg jpeg gif png txt doc xls pdf ppt pps
 *   odt ods odp". To allow all extensions, you must explicitly set this array
 *   to ['FileExtension' => []]. (Beware: this is not safe and should only be
 *   allowed for trusted users, if at all.)
 * @param string|false $destination
 *   (optional) A string containing the URI that the file should be copied to.
 *   This must be a stream wrapper URI. If this value is omitted or set to
 *   FALSE, Drupal's temporary files scheme will be used ("temporary://").
 * @param null|int $delta
 *   (optional) The delta of the file to return the file entity.
 *   Defaults to NULL.
 * @param \Drupal\Core\File\FileExists|int $fileExists
 *   (optional) The replace behavior when the destination file already exists.
 *
 * @return array|\Drupal\file\FileInterface|null|false
 *   An array of file entities or a single file entity if $delta != NULL. Each
 *   array element contains the file entity if the upload succeeded or FALSE if
 *   there was an error. Function returns NULL if no file was uploaded.
 *
 * @throws \ValueError
 *   Thrown if $fileExists is a legacy int and not a valid value.
 *
 * @see _file_save_upload_from_form()
 */
function file_save_upload($form_field_name, $validators = [], $destination = FALSE, $delta = NULL, FileExists|int $fileExists = FileExists::Rename) {
    if (!$fileExists instanceof FileExists) {
        // @phpstan-ignore staticMethod.deprecated
        $fileExists = FileExists::fromLegacyInt($fileExists, __METHOD__);
    }
    static $upload_cache;
    $all_files = \Drupal::request()->files
        ->get('files', []);
    // Make sure there's an upload to process.
    if (empty($all_files[$form_field_name])) {
        return NULL;
    }
    $file_upload = $all_files[$form_field_name];
    // Return cached objects without processing since the file will have
    // already been processed and the paths in $_FILES will be invalid.
    if (isset($upload_cache[$form_field_name])) {
        if (isset($delta)) {
            return $upload_cache[$form_field_name][$delta];
        }
        return $upload_cache[$form_field_name];
    }
    // Prepare uploaded files info. Representation is slightly different
    // for multiple uploads and we fix that here.
    $uploaded_files = $file_upload;
    if (!is_array($file_upload)) {
        $uploaded_files = [
            $file_upload,
        ];
    }
    if ($destination === FALSE || $destination === NULL) {
        $destination = 'temporary://';
    }
    
    /** @var \Drupal\file\Upload\FileUploadHandler $file_upload_handler */
    $file_upload_handler = \Drupal::service('file.upload_handler');
    
    /** @var \Drupal\Core\Render\RendererInterface $renderer */
    $renderer = \Drupal::service('renderer');
    $files = [];
    
    /** @var \Symfony\Component\HttpFoundation\File\UploadedFile $uploaded_file */
    foreach ($uploaded_files as $i => $uploaded_file) {
        try {
            $form_uploaded_file = new FormUploadedFile($uploaded_file);
            $result = $file_upload_handler->handleFileUpload($form_uploaded_file, $validators, $destination, $fileExists);
            if ($result->hasViolations()) {
                $errors = [];
                foreach ($result->getViolations() as $violation) {
                    $errors[] = $violation->getMessage();
                }
                $message = [
                    'error' => [
                        '#markup' => t('The specified file %name could not be uploaded.', [
                            '%name' => $uploaded_file->getClientOriginalName(),
                        ]),
                    ],
                    'item_list' => [
                        '#theme' => 'item_list',
                        '#items' => $errors,
                    ],
                ];
                // @todo Add support for render arrays in
                // \Drupal\Core\Messenger\MessengerInterface::addMessage()?
                // @see https://www.drupal.org/node/2505497.
                \Drupal::messenger()->addError($renderer->renderInIsolation($message));
                $files[$i] = FALSE;
                continue;
            }
            $file = $result->getFile();
            // If the filename has been modified, let the user know.
            if ($result->isRenamed()) {
                if ($result->isSecurityRename()) {
                    $message = t('For security reasons, your upload has been renamed to %filename.', [
                        '%filename' => $file->getFilename(),
                    ]);
                }
                else {
                    $message = t('Your upload has been renamed to %filename.', [
                        '%filename' => $file->getFilename(),
                    ]);
                }
                \Drupal::messenger()->addStatus($message);
            }
            $files[$i] = $file;
        } catch (FileExistsException) {
            \Drupal::messenger()->addError(t('Destination file "%file" exists', [
                '%file' => $destination . $uploaded_file->getFilename(),
            ]));
            $files[$i] = FALSE;
        } catch (InvalidStreamWrapperException) {
            \Drupal::messenger()->addError(t('The file could not be uploaded because the destination "%destination" is invalid.', [
                '%destination' => $destination,
            ]));
            $files[$i] = FALSE;
        } catch (FileWriteException) {
            \Drupal::messenger()->addError(t('File upload error. Could not move uploaded file.'));
            \Drupal::logger('file')->notice('Upload error. Could not move uploaded file %file to destination %destination.', [
                '%file' => $uploaded_file->getClientOriginalName(),
                '%destination' => $destination . '/' . $uploaded_file->getClientOriginalName(),
            ]);
            $files[$i] = FALSE;
        } catch (FileException) {
            \Drupal::messenger()->addError(t('The file %filename could not be uploaded because the name is invalid.', [
                '%filename' => $uploaded_file->getClientOriginalName(),
            ]));
            $files[$i] = FALSE;
        } catch (LockAcquiringException) {
            \Drupal::messenger()->addError(t('File already locked for writing.'));
            $files[$i] = FALSE;
        }
    }
    // Add files to the cache.
    $upload_cache[$form_field_name] = $files;
    return isset($delta) ? $files[$delta] : $files;
}

/**
 * Form submission handler for upload / remove buttons of managed_file elements.
 *
 * @see \Drupal\file\Element\ManagedFile::processManagedFile()
 */
function file_managed_file_submit($form, FormStateInterface $form_state) {
    // 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->getTriggeringElement()['#array_parents'];
    $button_key = array_pop($parents);
    $element = NestedArray::getValue($form, $parents);
    // No action is needed here for the upload button, because all file uploads on
    // the form are processed by \Drupal\file\Element\ManagedFile::valueCallback()
    // regardless of which button was clicked. Action is needed here for the
    // remove button, because we only remove a file in response to its remove
    // button being clicked.
    if ($button_key == 'remove_button') {
        $fids = array_keys($element['#files']);
        // Get files that will be removed.
        if ($element['#multiple']) {
            $remove_fids = [];
            foreach (Element::children($element) as $name) {
                if (str_starts_with($name, 'file_') && $element[$name]['selected']['#value']) {
                    $remove_fids[] = (int) substr($name, 5);
                }
            }
            $fids = array_diff($fids, $remove_fids);
        }
        else {
            // If we deal with single upload element remove the file and set
            // element's value to empty array (file could not be removed from
            // element if we don't do that).
            $remove_fids = $fids;
            $fids = [];
        }
        foreach ($remove_fids as $fid) {
            // If it's a temporary file we can safely remove it immediately, otherwise
            // it's up to the implementing module to remove usages of files to have them
            // removed.
            if ($element['#files'][$fid] && $element['#files'][$fid]->isTemporary()) {
                $element['#files'][$fid]->delete();
            }
        }
        // Update both $form_state->getValues() and FormState::$input to reflect
        // that the file has been removed, so that the form is rebuilt correctly.
        // $form_state->getValues() must be updated in case additional submit
        // handlers run, and for form building functions that run during the
        // rebuild, such as when the managed_file element is part of a field widget.
        // FormState::$input must be updated so that
        // \Drupal\file\Element\ManagedFile::valueCallback() has correct information
        // during the rebuild.
        $form_state->setValueForElement($element['fids'], implode(' ', $fids));
        NestedArray::setValue($form_state->getUserInput(), $element['fids']['#parents'], implode(' ', $fids));
    }
    // 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 calling $form_state->disableRedirect() would suffice.
    // However, we choose to always rebuild, to keep the form processing workflow
    // consistent between the two buttons.
    $form_state->setRebuild();
}

/**
 * Saves any files that have been uploaded into a managed_file element.
 *
 * @param array $element
 *   The FAPI element whose values are being saved.
 * @param \Drupal\Core\Form\FormStateInterface $form_state
 *   The current state of the form.
 *
 * @return array|false
 *   An array of file entities for each file that was saved, keyed by its file
 *   ID. Each array element contains a file entity. Function returns FALSE if
 *   upload directory could not be created or no files were uploaded.
 */
function file_managed_file_save_upload($element, FormStateInterface $form_state) {
    $upload_name = implode('_', $element['#parents']);
    $all_files = \Drupal::request()->files
        ->get('files', []);
    if (empty($all_files[$upload_name])) {
        return FALSE;
    }
    $file_upload = $all_files[$upload_name];
    $destination = $element['#upload_location'] ?? NULL;
    if (isset($destination) && !\Drupal::service('file_system')->prepareDirectory($destination, FileSystemInterface::CREATE_DIRECTORY)) {
        \Drupal::logger('file')->notice('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.', [
            '%directory' => $destination,
            '%name' => $element['#field_name'],
        ]);
        $form_state->setError($element, t('The file could not be uploaded.'));
        return FALSE;
    }
    // Save attached files to the database.
    $files_uploaded = $element['#multiple'] && count(array_filter($file_upload)) > 0;
    $files_uploaded |= !$element['#multiple'] && !empty($file_upload);
    if ($files_uploaded) {
        if (!($files = _file_save_upload_from_form($element, $form_state))) {
            \Drupal::logger('file')->notice('The file upload failed. %upload', [
                '%upload' => $upload_name,
            ]);
            return [];
        }
        // Value callback expects FIDs to be keys.
        $files = array_filter($files);
        $fids = array_map(function ($file) {
            return $file->id();
        }, $files);
        return empty($files) ? [] : array_combine($fids, $files);
    }
    return [];
}

/**
 * Prepares variables for file form widget templates.
 *
 * Default template: file-managed-file.html.twig.
 *
 * @param array $variables
 *   An associative array containing:
 *   - element: A render element representing the file.
 */
function template_preprocess_file_managed_file(&$variables) {
    $element = $variables['element'];
    $variables['attributes'] = [];
    if (isset($element['#id'])) {
        $variables['attributes']['id'] = $element['#id'];
    }
    if (!empty($element['#attributes']['class'])) {
        $variables['attributes']['class'] = (array) $element['#attributes']['class'];
    }
}

/**
 * Prepares variables for file link templates.
 *
 * Default template: file-link.html.twig.
 *
 * @param array $variables
 *   An associative array containing:
 *   - file: A File entity to which the link will be created.
 *   - icon_directory: (optional) A path to a directory of icons to be used for
 *     files. Defaults to the value of the "icon.directory" variable.
 *   - description: A description to be displayed instead of the filename.
 *   - attributes: An associative array of attributes to be placed in the a tag.
 */
function template_preprocess_file_link(&$variables) {
    $file = $variables['file'];
    $options = [];
    
    /** @var \Drupal\Core\File\FileUrlGeneratorInterface $file_url_generator */
    $file_url_generator = \Drupal::service('file_url_generator');
    $url = $file_url_generator->generate($file->getFileUri());
    $mime_type = $file->getMimeType();
    $options['attributes']['type'] = $mime_type;
    // Use the description as the link text if available.
    if (empty($variables['description'])) {
        $link_text = $file->getFilename();
    }
    else {
        $link_text = $variables['description'];
        $options['attributes']['title'] = $file->getFilename();
    }
    // Classes to add to the file field for icons.
    $classes = [
        'file',
        // Add a specific class for each and every mime type.
'file--mime-' . strtr($mime_type, [
            '/' => '-',
            '.' => '-',
        ]),
        // Add a more general class for groups of well known MIME types.
'file--' . IconMimeTypes::getIconClass($mime_type),
    ];
    // Set file classes to the options array.
    $variables['attributes'] = new Attribute($variables['attributes']);
    $variables['attributes']->addClass($classes);
    $variables['file_size'] = $file->getSize() !== NULL ? ByteSizeMarkup::create($file->getSize()) : '';
    $variables['link'] = Link::fromTextAndUrl($link_text, $url->mergeOptions($options))
        ->toRenderable();
}

/**
 * Prepares variables for multi file form widget templates.
 *
 * Default template: file-widget-multiple.html.twig.
 *
 * @param array $variables
 *   An associative array containing:
 *   - element: A render element representing the widgets.
 */
function template_preprocess_file_widget_multiple(&$variables) {
    $element = $variables['element'];
    // Special ID and classes for draggable tables.
    $weight_class = $element['#id'] . '-weight';
    $table_id = $element['#id'] . '-table';
    // Build up a table of applicable fields.
    $headers = [];
    $headers[] = t('File information');
    if ($element['#display_field']) {
        $headers[] = [
            'data' => t('Display'),
            'class' => [
                'checkbox',
            ],
        ];
    }
    $headers[] = t('Weight');
    $headers[] = t('Operations');
    // Get our list of widgets in order (needed when the form comes back after
    // preview or failed validation).
    $widgets = [];
    foreach (Element::children($element) as $key) {
        $widgets[] =& $element[$key];
    }
    usort($widgets, '_field_multiple_value_form_sort_helper');
    $rows = [];
    foreach ($widgets as &$widget) {
        // Save the uploading row for last.
        if (empty($widget['#files'])) {
            $widget['#title'] = $element['#file_upload_title'];
            $widget['#description'] = \Drupal::service('renderer')->renderInIsolation($element['#file_upload_description']);
            continue;
        }
        // Delay rendering of the buttons, so that they can be rendered later in the
        // "operations" column.
        $operations_elements = [];
        foreach (Element::children($widget) as $key) {
            if (isset($widget[$key]['#type']) && $widget[$key]['#type'] == 'submit') {
                hide($widget[$key]);
                $operations_elements[] =& $widget[$key];
            }
        }
        // Delay rendering of the "Display" option and the weight selector, so that
        // each can be rendered later in its own column.
        if ($element['#display_field']) {
            hide($widget['display']);
        }
        hide($widget['_weight']);
        $widget['_weight']['#attributes']['class'] = [
            $weight_class,
        ];
        // Render everything else together in a column, without the normal wrappers.
        $row = [];
        $widget['#theme_wrappers'] = [];
        $row[] = \Drupal::service('renderer')->render($widget);
        // Arrange the row with the rest of the rendered columns.
        if ($element['#display_field']) {
            unset($widget['display']['#title']);
            $row[] = [
                'data' => $widget['display'],
                'class' => [
                    'checkbox',
                ],
            ];
        }
        $row[] = [
            'data' => $widget['_weight'],
        ];
        // Show the buttons that had previously been marked as hidden in this
        // preprocess function. We use show() to undo the earlier hide().
        foreach (Element::children($operations_elements) as $key) {
            show($operations_elements[$key]);
        }
        $row[] = [
            'data' => $operations_elements,
        ];
        $rows[] = [
            'data' => $row,
            'class' => isset($widget['#attributes']['class']) ? array_merge($widget['#attributes']['class'], [
                'draggable',
            ]) : [
                'draggable',
            ],
        ];
    }
    $variables['table'] = [
        '#type' => 'table',
        '#header' => $headers,
        '#rows' => $rows,
        '#attributes' => [
            'id' => $table_id,
        ],
        '#tabledrag' => [
            [
                'action' => 'order',
                'relationship' => 'sibling',
                'group' => $weight_class,
            ],
        ],
        '#access' => !empty($rows),
    ];
    $variables['element'] = $element;
}

/**
 * Prepares variables for file upload help text templates.
 *
 * Default template: file-upload-help.html.twig.
 *
 * @param array $variables
 *   An associative array containing:
 *   - description: The normal description for this field, specified by the
 *     user.
 *   - upload_validators: An array of upload validators as used in
 *     $element['#upload_validators'].
 */
function template_preprocess_file_upload_help(&$variables) {
    $description = $variables['description'];
    $upload_validators = $variables['upload_validators'];
    $cardinality = $variables['cardinality'];
    $descriptions = [];
    if (!empty($description)) {
        $descriptions[] = FieldFilteredMarkup::create($description);
    }
    if (isset($cardinality)) {
        if ($cardinality == -1) {
            $descriptions[] = t('Unlimited number of files can be uploaded to this field.');
        }
        else {
            $descriptions[] = \Drupal::translation()->formatPlural($cardinality, 'One file only.', 'Maximum @count files.');
        }
    }
    if (isset($upload_validators['FileSizeLimit'])) {
        $descriptions[] = t('@size limit.', [
            '@size' => ByteSizeMarkup::create($upload_validators['FileSizeLimit']['fileLimit']),
        ]);
    }
    if (isset($upload_validators['FileExtension'])) {
        $descriptions[] = t('Allowed types: @extensions.', [
            '@extensions' => $upload_validators['FileExtension']['extensions'],
        ]);
    }
    if (isset($upload_validators['FileImageDimensions'])) {
        $max = $upload_validators['FileImageDimensions']['maxDimensions'];
        $min = $upload_validators['FileImageDimensions']['minDimensions'];
        if ($min && $max && $min == $max) {
            $descriptions[] = t('Images must be exactly <strong>@size</strong> pixels.', [
                '@size' => $max,
            ]);
        }
        elseif ($min && $max) {
            $descriptions[] = t('Images must be larger than <strong>@min</strong> pixels. Images larger than <strong>@max</strong> pixels will be resized.', [
                '@min' => $min,
                '@max' => $max,
            ]);
        }
        elseif ($min) {
            $descriptions[] = t('Images must be larger than <strong>@min</strong> pixels.', [
                '@min' => $min,
            ]);
        }
        elseif ($max) {
            $descriptions[] = t('Images larger than <strong>@max</strong> pixels will be resized.', [
                '@max' => $max,
            ]);
        }
    }
    $variables['descriptions'] = $descriptions;
}

/**
 * Retrieves a list of references to a file.
 *
 * @param \Drupal\file\FileInterface $file
 *   A file entity.
 * @param \Drupal\Core\Field\FieldDefinitionInterface|null $field
 *   (optional) A field definition to be used for this check. If given,
 *   limits the reference check to the given field. Defaults to NULL.
 * @param int $age
 *   (optional) A constant that specifies which references to count. Use
 *   EntityStorageInterface::FIELD_LOAD_REVISION (the default) to retrieve all
 *   references within all revisions or
 *   EntityStorageInterface::FIELD_LOAD_CURRENT to retrieve references only in
 *   the current revisions of all entities that have references to this file.
 * @param string $field_type
 *   (optional) The name of a field type. If given, limits the reference check
 *   to fields of the given type. If both $field and $field_type are given but
 *   $field is not the same type as $field_type, an empty array will be
 *   returned. Defaults to 'file'.
 *
 * @return array
 *   A multidimensional array. The keys are field_name, entity_type,
 *   entity_id and the value is an entity referencing this file.
 *
 * @ingroup file
 */
function file_get_file_references(FileInterface $file, ?FieldDefinitionInterface $field = NULL, $age = EntityStorageInterface::FIELD_LOAD_REVISION, $field_type = 'file') {
    $references =& drupal_static(__FUNCTION__, []);
    $field_columns =& drupal_static(__FUNCTION__ . ':field_columns', []);
    // Fill the static cache, disregard $field and $field_type for now.
    if (!isset($references[$file->id()][$age])) {
        $references[$file->id()][$age] = [];
        $usage_list = \Drupal::service('file.usage')->listUsage($file);
        $file_usage_list = $usage_list['file'] ?? [];
        foreach ($file_usage_list as $entity_type_id => $entity_ids) {
            $entities = \Drupal::entityTypeManager()->getStorage($entity_type_id)
                ->loadMultiple(array_keys($entity_ids));
            foreach ($entities as $entity) {
                $bundle = $entity->bundle();
                // We need to find file fields for this entity type and bundle.
                if (!isset($file_fields[$entity_type_id][$bundle])) {
                    $file_fields[$entity_type_id][$bundle] = [];
                    // This contains the possible field names.
                    foreach ($entity->getFieldDefinitions() as $field_name => $field_definition) {
                        // If this is the first time this field type is seen, check
                        // whether it references files.
                        if (!isset($field_columns[$field_definition->getType()])) {
                            $field_columns[$field_definition->getType()] = file_field_find_file_reference_column($field_definition);
                        }
                        // If the field type does reference files then record it.
                        if ($field_columns[$field_definition->getType()]) {
                            $file_fields[$entity_type_id][$bundle][$field_name] = $field_columns[$field_definition->getType()];
                        }
                    }
                }
                foreach ($file_fields[$entity_type_id][$bundle] as $field_name => $field_column) {
                    // Iterate over the field items to find the referenced file and field
                    // name. This will fail if the usage checked is in a non-current
                    // revision because field items are from the current
                    // revision.
                    // We also iterate over all translations because a file can be linked
                    // to a language other than the default.
                    foreach ($entity->getTranslationLanguages() as $langcode => $language) {
                        foreach ($entity->getTranslation($langcode)
                            ->get($field_name) as $item) {
                            if ($file->id() == $item->{$field_column}) {
                                $references[$file->id()][$age][$field_name][$entity_type_id][$entity->id()] = $entity;
                                break;
                            }
                        }
                    }
                }
            }
        }
    }
    $return = $references[$file->id()][$age];
    // Filter the static cache down to the requested entries. The usual static
    // cache is very small so this will be very fast.
    $entity_field_manager = \Drupal::service('entity_field.manager');
    if ($field || $field_type) {
        foreach ($return as $field_name => $data) {
            foreach (array_keys($data) as $entity_type_id) {
                $field_storage_definitions = $entity_field_manager->getFieldStorageDefinitions($entity_type_id);
                $current_field = $field_storage_definitions[$field_name];
                if ($field_type && $current_field->getType() != $field_type || $field && $field->uuid() != $current_field->uuid()) {
                    unset($return[$field_name][$entity_type_id]);
                }
            }
        }
    }
    return $return;
}

/**
 * Determine whether a field references files stored in {file_managed}.
 *
 * @param \Drupal\Core\Field\FieldDefinitionInterface $field
 *   A field definition.
 *
 * @return bool
 *   The field column if the field references {file_managed}.fid, typically
 *   fid, FALSE if it does not.
 */
function file_field_find_file_reference_column(FieldDefinitionInterface $field) {
    $schema = $field->getFieldStorageDefinition()
        ->getSchema();
    foreach ($schema['foreign keys'] as $data) {
        if ($data['table'] == 'file_managed') {
            foreach ($data['columns'] as $field_column => $column) {
                if ($column == 'fid') {
                    return $field_column;
                }
            }
        }
    }
    return FALSE;
}

/**
 * Form submission handler for file system settings form.
 */
function file_system_settings_submit(array &$form, FormStateInterface $form_state) {
    $config = \Drupal::configFactory()->getEditable('file.settings')
        ->set('filename_sanitization', $form_state->getValue('filename_sanitization'));
    $config->save();
}

Functions

Title Deprecated Summary
file_field_find_file_reference_column Determine whether a field references files stored in {file_managed}.
file_get_content_headers Examines a file entity and returns appropriate content headers for download.
file_get_file_references Retrieves a list of references to a file.
file_managed_file_save_upload Saves any files that have been uploaded into a managed_file element.
file_managed_file_submit Form submission handler for upload / remove buttons of managed_file elements.
file_save_upload Saves file uploads to a new location.
file_system_settings_submit Form submission handler for file system settings form.
template_preprocess_file_link Prepares variables for file link templates.
template_preprocess_file_managed_file Prepares variables for file form widget templates.
template_preprocess_file_upload_help Prepares variables for file upload help text templates.
template_preprocess_file_widget_multiple Prepares variables for multi file form widget templates.
_file_save_upload_from_form Saves form file uploads.

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