Code style cleanup, mostly comments and PHPdoc.
[project/filefield.git] / filefield.module
1 <?php
2 // $Id$
3
4 /**
5 * @file
6 * FileField: Defines a CCK file field type.
7 *
8 * Uses content.module to store the fid and field specific metadata,
9 * and Drupal's {files} table to store the actual file data.
10 */
11
12 include_once('field_file.inc');
13
14 /**
15 * Implementation of hook_init().
16 */
17 function filefield_init() {
18 // File hooks and callbacks may be used by any module.
19 module_load_include('inc', 'filefield', 'filefield_widget');
20 drupal_add_css(drupal_get_path('module', 'filefield') .'/filefield.css');
21
22 // Conditional module support.
23 if (module_exists('token')) {
24 module_load_include('inc', 'filefield', 'filefield.token');
25 }
26 }
27
28 /**
29 * Implementation of hook_menu().
30 */
31 function filefield_menu() {
32 $items = array();
33
34 $items['filefield/ahah/%/%/%'] = array(
35 'page callback' => 'filefield_js',
36 'page arguments' => array(2, 3, 4),
37 'access callback' => 'filefield_edit_access',
38 'access arguments' => array(3),
39 'type' => MENU_CALLBACK,
40 );
41 return $items;
42 }
43
44 /**
45 * Implementation of hook_elements().
46 * @todo: autogenerate element registry entries for widgets.
47 */
48 function filefield_elements() {
49 $elements = array();
50 $elements['filefield_widget'] = array(
51 '#input' => TRUE,
52 '#columns' => array('fid', 'list', 'data'),
53 '#process' => array('filefield_widget_process'),
54 '#value_callback' => 'filefield_widget_value',
55 '#element_validate' => array('filefield_widget_validate'),
56 '#description' => t('Changes made to the attachments are not permanent until you save this post.'),
57 );
58 return $elements;
59 }
60
61 /**
62 * Implementation of hook_theme().
63 * @todo: autogenerate theme registry entrys for widgets.
64 */
65 function filefield_theme() {
66 return array(
67 'filefield_file' => array(
68 'arguments' => array('file' => NULL),
69 'file' => 'filefield_formatter.inc',
70 ),
71 'filefield_icon' => array(
72 'arguments' => array('file' => NULL),
73 'file' => 'filefield.theme.inc',
74 ),
75 'filefield_widget' => array(
76 'arguments' => array('element' => NULL),
77 'file' => 'filefield_widget.inc',
78 ),
79 'filefield_widget_item' => array(
80 'arguments' => array('element' => NULL),
81 'file' => 'filefield_widget.inc',
82 ),
83 'filefield_widget_preview' => array(
84 'arguments' => array('element' => NULL),
85 'file' => 'filefield_widget.inc',
86 ),
87 'filefield_widget_file' => array(
88 'arguments' => array('element' => NULL),
89 'file' => 'filefield_widget.inc',
90 ),
91
92
93 'filefield_formatter_default' => array(
94 'arguments' => array('element' => NULL),
95 'file' => 'filefield_formatter.inc',
96 ),
97 'filefield_formatter_url_plain' => array(
98 'arguments' => array('element' => NULL),
99 'file' => 'filefield_formatter.inc',
100 ),
101 'filefield_formatter_path_plain' => array(
102 'arguments' => array('element' => NULL),
103 'file' => 'filefield_formatter.inc',
104 ),
105 'filefield_item' => array(
106 'arguments' => array('file' => NULL, 'field' => NULL),
107 'file' => 'filefield_formatter.inc',
108 ),
109 'filefield_file' => array(
110 'arguments' => array('file' => NULL),
111 'file' => 'filefield_formatter.inc',
112 ),
113
114 );
115 }
116
117 /**
118 * Implementation of hook_file_download(). Yes, *that* hook that causes
119 * any attempt for file upload module interoperability to fail spectacularly.
120 */
121 function filefield_file_download($file) {
122 $file = file_create_path($file);
123
124 $result = db_query("SELECT * FROM {files} WHERE filepath = '%s'", $file);
125 if (!$file = db_fetch_object($result)) {
126 // We don't really care about this file.
127 return;
128 }
129
130 // Find out if any filefield contains this file, and if so, which field
131 // and node it belongs to. Required for later access checking.
132 $cck_files = array();
133 foreach (content_fields() as $field) {
134 if ($field['type'] == 'filefield' || $field['type'] == 'image') {
135 $db_info = content_database_info($field);
136 $table = $db_info['table'];
137 $fid_column = $db_info['columns']['fid']['column'];
138
139 $columns = array('vid', 'nid');
140 foreach ($db_info['columns'] as $property_name => $column_info) {
141 $columns[] = $column_info['column'] .' AS '. $property_name;
142 }
143 $result = db_query("SELECT ". implode(', ', $columns) ."
144 FROM {". $table ."}
145 WHERE ". $fid_column ." = %d", $file->fid);
146
147 while ($content = db_fetch_array($result)) {
148 $content['field'] = $field;
149 $cck_files[$field['field_name']][$content['vid']] = $content;
150 }
151 }
152 }
153 // If no filefield item is involved with this file, we don't care about it.
154 if (empty($cck_files)) {
155 return;
156 }
157
158 // If any node includes this file but the user may not view this field,
159 // then deny the download.
160 foreach ($cck_files as $field_name => $field_files) {
161 if (!filefield_view_access($field_name)) {
162 return -1;
163 }
164 }
165
166 // So the overall field view permissions are not denied, but if access is
167 // denied for a specific node containing the file, deny the download as well.
168 // It's probably a little too restrictive, but I can't think of a
169 // better way at the moment. Input appreciated.
170 // (And yeah, node access checks also include checking for 'access content'.)
171 $nodes = array();
172 foreach ($cck_files as $field_name => $field_files) {
173 foreach ($field_files as $revision_id => $content) {
174 // Checking separately for each revision is probably not the best idea -
175 // what if 'view revisions' is disabled? So, let's just check for the
176 // current revision of that node.
177 if (isset($nodes[$content['nid']])) {
178 continue; // don't check the same node twice
179 }
180 $node = node_load($content['nid']);
181 if (!node_access('view', $node)) {
182 // You don't have permission to view the node this file is attached to.
183 return -1;
184 }
185 $nodes[$content['nid']] = $node;
186 }
187 }
188
189 // Well I guess you can see this file.
190 $name = mime_header_encode($file->filename);
191 $type = mime_header_encode($file->filemime);
192 // Serve images and text inline for the browser to display rather than download.
193 $disposition = ereg('^(text/|image/)', $file->filemime) ? 'inline' : 'attachment';
194 return array(
195 'Content-Type: '. $type .'; name='. $name,
196 'Content-Length: '. $file->filesize,
197 'Content-Disposition: '. $disposition .'; filename='. $name,
198 'Cache-Control: private',
199 );
200 }
201
202 /**
203 * Implementation of hook_form_alter().
204 *
205 * Set the appropriate attibutes to allow file uploads on the field settings
206 * form.
207 */
208 function filefield_form_alter(&$form, $form_state, $form_id) {
209 if ($form_id == 'content_field_edit_form' && isset($form['#field']) && $form['#field']['type'] == 'filefield') {
210 $form['#attributes']['enctype'] = 'multipart/form-data';
211 }
212
213 if (preg_match('/_node_form$/', $form_id)) {
214 $form['#attributes']['enctype'] = 'multipart/form-data';
215 }
216 }
217
218 /**
219 * Implementation of CCK's hook_field_info().
220 */
221 function filefield_field_info() {
222 return array(
223 'filefield' => array(
224 'label' => 'File',
225 'description' => t('Store an arbitrary file.'),
226 ),
227 );
228 }
229
230 /**
231 * Implementation of hook_field_settings().
232 */
233 function filefield_field_settings($op, $field) {
234 $return = array();
235
236 module_load_include('inc', 'filefield', 'filefield_field');
237 $op = str_replace(' ', '_', $op);
238 // add filefield specific handlers...
239 $function = 'filefield_field_settings_'. $op;
240 if (function_exists($function)) {
241 $result = $function($field);
242 if (isset($result) && is_array($result)) {
243 $return = $result;
244 }
245 }
246
247 // dynamically load widgets file and callbacks for other fields utilizing
248 // filefield's hook_field_settings implementation.
249 module_load_include('inc', $field['module'], $field['type'] .'_field');
250 $function = $field['module'] .'_'. $field['type'] .'_field_settings_'. $op;
251 if (function_exists($function)) {
252 $result = $function($field);
253 if (isset($result) && is_array($result)) {
254 $return = array_merge($return, $result);
255 }
256 }
257
258 return $return;
259
260 }
261
262 /**
263 * Implementtation of CCK's hook_field().
264 */
265 function filefield_field($op, $node, $field, &$items, $teaser, $page) {
266 module_load_include('inc', 'filefield', 'filefield_field');
267 $op = str_replace(' ', '_', $op);
268 // add filefield specific handlers...
269 $function = 'filefield_field_'. $op;
270 if (function_exists($function)) {
271 return $function($node, $field, $items, $teaser, $page);
272 }
273 }
274
275 /**
276 * Implementation of CCK's hook_widget_settings().
277 */
278 function filefield_widget_settings($op, $widget) {
279 switch ($op) {
280 case 'form':
281 return filefield_widget_settings_form($widget);
282 case 'save':
283 return filefield_widget_settings_save($widget);
284 }
285 }
286
287 /**
288 * Implementation of hook_widget().
289 */
290 function filefield_widget(&$form, &$form_state, $field, $items, $delta = 0) {
291 // CCK doesn't give a validate callback at the field level...
292 // and FAPI's #require is naieve to complex structures...
293 // we validate at the field level ourselves.
294 if (empty($form['#validate']) || !in_array('filefield_node_form_validate', $form['#validate'])) {
295 $form['#validate'][] = 'filefield_node_form_validate';
296 }
297 if (empty($form['#submit']) || !in_array('filefield_node_form_submit', $form['#submit'])) {
298 $form['#submit'][] = 'filefield_node_form_submit';
299 }
300 $form['#attributes'] = array('enctype' => 'multipart/form-data');
301
302 module_load_include('inc', 'filefield', 'field_widget');
303 module_load_include('inc', $field['widget']['module'], $field['widget']['module'] .'_widget');
304
305 $item = array('fid' => 0, 'list' => $field['list_default'], 'data' => array('description' => ''));
306 if (isset($items[$delta])) {
307 $item = array_merge($item, $items[$delta]);
308 }
309 $element = array(
310 '#title' => $field['widget']['label'],
311 '#type' => $field['widget']['type'],
312 '#default_value' => $item,
313 '#upload_validators' => filefield_widget_upload_validators($field),
314 );
315
316 return $element;
317 }
318
319 /**
320 * Get the upload validators for a file field.
321 *
322 * @param $field
323 * A CCK field array.
324 * @return
325 * An array suitable for passing to file_save_upload() or the file field
326 * element's '#upload_validators' property.
327 */
328 function filefield_widget_upload_validators($field) {
329 $max_filesize = parse_size(file_upload_max_size());
330 if (!empty($field['widget']['max_filesize_per_file']) && parse_size($field['widget']['max_filesize_per_file']) < $max_filesize) {
331 $max_filesize = parse_size($field['widget']['max_filesize_per_file']);
332 }
333
334 $validators = array(
335 // associate the field to the file on validation.
336 'filefield_validate_associate_field' => array($field),
337 'filefield_validate_size' => array($max_filesize),
338 // Override core since it excludes uid 1 on the extension check.
339 // Filefield only excuses uid 1 of quota requirements.
340 'filefield_validate_extensions' => array($field['widget']['file_extensions']),
341 );
342 return $validators;
343 }
344
345 /**
346 * Implementation of CCK's hook_content_is_empty().
347 *
348 * The result of this determines whether content.module will save the value of
349 * the field. Note that content module has some interesting behaviors for empty
350 * values. It will always save at least one record for every node revision,
351 * even if the values are all NULL. If it is a multi-value field with an
352 * explicit limit, CCK will save that number of empty entries.
353 */
354 function filefield_content_is_empty($item, $field) {
355 return empty($item['fid']) || (int)$item['fid'] == 0;
356 }
357
358 /**
359 * Implementation of CCK's hook_widget_info().
360 */
361 function filefield_widget_info() {
362 return array(
363 'filefield_widget' => array(
364 'label' => t('File Upload'),
365 'field types' => array('filefield'),
366 'multiple values' => CONTENT_HANDLE_CORE,
367 'callbacks' => array('default value' => CONTENT_CALLBACK_CUSTOM),
368 'description' => t('A plain file upload widget.'),
369 ),
370 );
371 }
372
373 /**
374 * Implementation of CCK's hook_field_formatter_info().
375 */
376 function filefield_field_formatter_info() {
377 return array(
378 'default' => array(
379 'label' => t('Generic files'),
380 'field types' => array('filefield'),
381 'multiple values' => CONTENT_HANDLE_CORE,
382 'description' => t('Displays all kinds of files with an icon and a linked file description.'),
383 ),
384 'path_plain' => array(
385 'label' => t('Path to file'),
386 'field types' => array('filefield'),
387 'description' => t('Displays the file system path to the file.'),
388 ),
389 'url_plain' => array(
390 'label' => t('URL to file'),
391 'field types' => array('filefield'),
392 'description' => t('Displays a full URL to the file.'),
393 ),
394 );
395 }
396
397 /**
398 * Determine the most appropriate icon for the given file's mimetype.
399 *
400 * @param $file
401 * A file object.
402 * @return
403 * The URL of the icon image file, or FALSE if no icon could be found.
404 */
405 function filefield_icon_url($file) {
406 include_once(drupal_get_path('module', 'filefield') .'/filefield.theme.inc');
407 return _filefield_icon_url($file);
408 }
409
410 /**
411 * Access callback for the JavaScript upload and deletion AHAH callbacks.
412 *
413 * The content_permissions module provides nice fine-grained permissions for
414 * us to check, so we can make sure that the user may actually edit the file.
415 */
416 function filefield_edit_access($field_name) {
417 if (module_exists('content_permissions')) {
418 return user_access('edit '. $field_name);
419 }
420 // No content permissions to check, so let's fall back to a more general permission.
421 return user_access('access content');
422 }
423
424 /**
425 * Access callback that checks if the current user may view the filefield.
426 */
427 function filefield_view_access($field_name) {
428 if (module_exists('content_permissions')) {
429 return user_access('view '. $field_name);
430 }
431 // No content permissions to check, so let's fall back to a more general permission.
432 return user_access('access content');
433 }
434
435 /**
436 * Menu callback; Shared AHAH callback for uploads and deletions.
437 *
438 * This rebuilds the form element for a particular field item. As long as the
439 * form processing is properly encapsulated in the widget element the form
440 * should rebuild correctly using FAPI without the need for additional callbacks
441 * or processing.
442 */
443 function filefield_js($type_name, $field_name, $delta) {
444 $field = content_fields($field_name, $type_name);
445
446 if (empty($field) || empty($_POST['form_build_id'])) {
447 // Invalid request.
448 print drupal_to_js(array('data' => ''));
449 exit;
450 }
451
452 // Build the new form.
453 $form_state = array('submitted' => FALSE);
454 $form_build_id = $_POST['form_build_id'];
455 $form = form_get_cache($form_build_id, $form_state);
456
457 if (!$form) {
458 // Invalid form_build_id.
459 print drupal_to_js(array('data' => ''));
460 exit;
461 }
462
463 // Build the form. This calls the file field's #value_callback function and
464 // saves the uploaded file. Since this form is already marked as cached
465 // (the #cache property is TRUE), the cache is updated automatically and we
466 // don't need to call form_set_cache().
467 $args = $form['#parameters'];
468 $form_id = array_shift($args);
469 $form['#post'] = $_POST;
470 $form = form_builder($form_id, $form, $form_state);
471
472 // Update the cached form with the new element at the right place in the form.
473 if (module_exists('fieldgroup') && ($group_name = _fieldgroup_field_get_group($type_name, $field_name))) {
474 if (isset($form['#multigroups']) && isset($form['#multigroups'][$group_name][$field_name])) {
475 $form_element = $form[$group_name][$delta][$field_name];
476 }
477 else {
478 $form_element = $form[$group_name][$field_name][$delta];
479 }
480 }
481 else {
482 $form_element = $form[$field_name][$delta];
483 }
484
485 if (isset($form_element['_weight'])) {
486 unset($form_element['_weight']);
487 }
488
489 $output = drupal_render($form_element);
490
491 // AHAH is not being nice to us and doesn't know the "other" button (that is,
492 // either "Upload" or "Delete") yet. Which in turn causes it not to attach
493 // AHAH behaviours after replacing the element. So we need to tell it first.
494
495 // Loop through the JS settings and find the settings needed for our buttons.
496 $javascript = drupal_add_js(NULL, NULL);
497 $filefield_ahah_settings = array();
498 if (isset($javascript['setting'])) {
499 foreach ($javascript['setting'] as $settings) {
500 if (isset($settings['ahah'])) {
501 foreach ($settings['ahah'] as $id => $ahah_settings) {
502 if (strpos($id, 'filefield-upload') || strpos($id, 'filefield-remove')) {
503 $filefield_ahah_settings[$id] = $ahah_settings;
504 }
505 }
506 }
507 }
508 }
509
510 // Add the AHAH settings needed for our new buttons.
511 if (!empty($filefield_ahah_settings)) {
512 $output .= '<script type="text/javascript">jQuery.extend(Drupal.settings.ahah, '. drupal_to_js($filefield_ahah_settings) .');</script>';
513 }
514
515 $output = theme('status_messages') . $output;
516
517 // For some reason, file uploads don't like drupal_json() with its manual
518 // setting of the text/javascript HTTP header. So use this one instead.
519 $GLOBALS['devel_shutdown'] = FALSE;
520 print drupal_to_js(array('status' => TRUE, 'data' => $output));
521 exit;
522 }
523
524 /**
525 * Implementation of hook_file_references().
526 */
527 function filefield_file_references($file) {
528 $references = 0;
529 foreach (content_fields() as $field) {
530 if ($field['type'] != 'filefield') {
531 continue;
532 }
533 $references += field_file_references($file, $field);
534 }
535 return array('filefield' => $references);
536 }
537
538 /**
539 * Implementation of hook_file_delete().
540 */
541 function filefield_file_delete($file) {
542 // foreach field... remove items referencing $file.
543 }
544
545 /**
546 * An #upload_validators callback. Check the file matches an allowed extension.
547 *
548 * If the mimedetect module is available, this will also validate that the
549 * content of the file matches the extension. User #1 is included in this check.
550 *
551 * @param $file
552 * A Drupal file object.
553 * @param $extensions
554 * A string with a space separated list of allowed extensions.
555 * @return
556 * An array of any errors cause by this file if it failed validation.
557 */
558 function filefield_validate_extensions($file, $extensions) {
559 global $user;
560 $errors = array();
561
562 if (!empty($extensions)) {
563 $regex = '/\.('. ereg_replace(' +', '|', preg_quote($extensions)) .')$/i';
564 $matches = array();
565 if (preg_match($regex, $file->filename, $matches)) {
566 $extension = $matches[1];
567 // If the extension validates, check that the mimetype matches.
568 if (module_exists('mimedetect')) {
569 $type = mimedetect_mime($file);
570 if ($type != $file->filemime) {
571 $errors[] = t('The file contents (@type) do not match its extension (@extension).', array('@type' => $type, '@extension' => $extension));
572 }
573 }
574 }
575 else {
576 $errors[] = t('Only files with the following extensions are allowed: %files-allowed.', array('%files-allowed' => $extensions));
577 }
578 }
579
580 return $errors;
581 }
582
583 /**
584 * Help text automatically appended to fields that have extension validation.
585 */
586 function filefield_validate_extensions_help($extensions) {
587 if (!empty($extensions)) {
588 return t('Allowed Extensions: %ext', array('%ext' => $extensions));
589 }
590 else {
591 return '';
592 }
593 }
594
595 /**
596 * An #upload_validators callback. Check the file size does not exceed a limit.
597 *
598 * @param $file
599 * A Drupal file object.
600 * @param $file_limit
601 * An integer value limiting the maximum file size in bytes.
602 * @param $file_limit
603 * An integer value limiting the maximum size in bytes a user can upload on
604 * the entire site.
605 * @return
606 * An array of any errors cause by this file if it failed validation.
607 */
608 function filefield_validate_size($file, $file_limit = 0, $user_limit = 0) {
609 global $user;
610
611 $errors = array();
612
613 if ($file_limit && $file->filesize > $file_limit) {
614 $errors[] = t('The file is %filesize exceeding the maximum file size of %maxsize.', array('%filesize' => format_size($file->filesize), '%maxsize' => format_size($file_limit)));
615 }
616
617 // Bypass user limits for uid = 1.
618 if ($user->uid != 1) {
619 $total_size = file_space_used($user->uid) + $file->filesize;
620 if ($user_limit && $total_size > $user_limit) {
621 $errors[] = t('The file is %filesize which would exceed your disk quota of %quota.', array('%filesize' => format_size($file->filesize), '%quota' => format_size($user_limit)));
622 }
623 }
624 return $errors;
625 }
626
627 /**
628 * Automatic help text appended to fields that have file size validation.
629 */
630 function filefield_validate_size_help($size) {
631 return t('Maximum Filesize: %size', array('%size' => format_size(parse_size($size))));
632 }
633
634 /**
635 * An #upload_validators callback. Check an image resolution.
636 *
637 * @param $file
638 * A Drupal file object.
639 * @param $max_size
640 * A string in the format WIDTHxHEIGHT. If the image is larger than this size
641 * the image will be scaled to fit within these dimensions.
642 * @param $min_size
643 * A string in the format WIDTHxHEIGHT. If the image is smaller than this size
644 * a validation error will be returned.
645 * @return
646 * An array of any errors cause by this file if it failed validation.
647 */
648 function filefield_validate_image_resolution(&$file, $maximum_dimensions = 0, $minimum_dimensions = 0) {
649 $errors = array();
650
651 // Check first that the file is an image.
652 if ($info = image_get_info($file->filepath)) {
653 if ($maximum_dimensions) {
654 // Check that it is smaller than the given dimensions.
655 list($width, $height) = explode('x', $maximum_dimensions);
656 if ($info['width'] > $width || $info['height'] > $height) {
657 // Try to resize the image to fit the dimensions.
658 if (image_get_toolkit() && image_scale($file->filepath, $file->filepath, $width, $height)) {
659 drupal_set_message(t('The image was resized to fit within the maximum allowed dimensions of %dimensions pixels.', array('%dimensions' => $maximum_dimensions)));
660
661 // Clear the cached filesize and refresh the image information.
662 clearstatcache();
663 $info = image_get_info($file->filepath);
664 $file->filesize = $info['file_size'];
665 }
666 else {
667 $errors[] = t('The image is too large; the maximum dimensions are %dimensions pixels.', array('%dimensions' => $maximum_dimensions));
668 }
669 }
670 }
671
672 if ($minimum_dimensions) {
673 // Check that it is larger than the given dimensions.
674 list($width, $height) = explode('x', $minimum_dimensions);
675 if ($info['width'] < $width || $info['height'] < $height) {
676 $errors[] = t('The image is too small; the minimum dimensions are %dimensions pixels.', array('%dimensions' => $minimum_dimensions));
677 }
678 }
679 }
680
681 return $errors;
682 }
683
684 /**
685 * Automatic help text appended to fields that have image resolution validation.
686 */
687 function filefield_validate_image_resolution_help($max_size = '0', $min_size = '0') {
688 if (!empty($max_size)) {
689 if (!empty($min_size)) {
690 if ($max_size == $min_size) {
691 return t('Images must be exactly @min_size pixels', array('@min_size' => $min_size));
692 }
693 else {
694 return t('Images must be between @min_size pixels and @max_size', array('@max_size' => $max_size, '@min_size' => $min_size));
695 }
696 }
697 else {
698 if (image_get_toolkit()) {
699 return t('Images larger than @max_size pixels will be scaled', array('@max_size' => $max_size));
700 }
701 else {
702 return t('Images must be smaller than @max_size pixels', array('@max_size' => $max_size));
703 }
704 }
705 }
706 if (!empty($min_size)) {
707 return t('Images must be larger than @max_size pixels', array('@max_size' => $min_size));
708 }
709 }
710
711
712 /**
713 * An #upload_validators callback. Check that a file is an image.
714 *
715 * This check should allow any image that PHP can identify, including png, jpg,
716 * gif, tif, bmp, psd, swc, iff, jpc, jp2, jpx, jb2, xbm, and wbmp.
717 *
718 * This check should be combined with filefield_validate_extensions() to ensure
719 * only web-based images are allowed, however it provides a better check than
720 * extension checking alone if the mimedetect module is not available.
721 *
722 * @param $file
723 * A Drupal file object.
724 * @return
725 * An array of any errors cause by this file if it failed validation.
726 */
727 function filefield_validate_is_image(&$file) {
728 $errors = array();
729 $info = image_get_info($file->filepath);
730 if (!$info || empty($info['extension'])) {
731 $errors[] = t('The file is not a known image format.');
732 }
733 return $errors;
734 }
735
736 /**
737 * An #upload_validators callback. Add the field to the file object.
738 *
739 * This validation function adds the field to the file object for later
740 * use in field aware modules implementing hook_file. It's not truly a
741 * validation at all, rather a convient way to add properties to the uploaded
742 * file.
743 */
744 function filefield_validate_associate_field(&$file, $field) {
745 $file->field = $field;
746 return array();
747 }