1<?php
2/**
3 * The plugin API is located in this file, which allows for creating actions
4 * and filters and hooking functions, and methods. The functions or methods will
5 * then be run when the action or filter is called.
6 *
7 * The API callback examples reference functions, but can be methods of classes.
8 * To hook methods, you'll need to pass an array one of two ways.
9 *
10 * Any of the syntaxes explained in the PHP documentation for the
11 * {@link https://www.php.net/manual/en/language.pseudo-types.php#language.types.callback 'callback'}
12 * type are valid.
13 *
14 * Also see the {@link https://developer.wordpress.org/plugins/ Plugin API} for
15 * more information and examples on how to use a lot of these functions.
16 *
17 * This file should have no external dependencies.
18 *
19 * @package WordPress
20 * @subpackage Plugin
21 * @since 1.5.0
22 */
23
24// Initialize the filter globals.
25require __DIR__ . '/class-wp-hook.php';
26
27/** @var WP_Hook[] $wp_filter */
28global $wp_filter;
29
30/** @var int[] $wp_actions */
31global $wp_actions;
32
33/** @var int[] $wp_filters */
34global $wp_filters;
35
36/** @var string[] $wp_current_filter */
37global $wp_current_filter;
38
39if ( $wp_filter ) {
40 $wp_filter = WP_Hook::build_preinitialized_hooks( $wp_filter );
41} else {
42 $wp_filter = array();
43}
44
45if ( ! isset( $wp_actions ) ) {
46 $wp_actions = array();
47}
48
49if ( ! isset( $wp_filters ) ) {
50 $wp_filters = array();
51}
52
53if ( ! isset( $wp_current_filter ) ) {
54 $wp_current_filter = array();
55}
56
57/**
58 * Adds a callback function to a filter hook.
59 *
60 * WordPress offers filter hooks to allow plugins to modify
61 * various types of internal data at runtime.
62 *
63 * A plugin can modify data by binding a callback to a filter hook. When the filter
64 * is later applied, each bound callback is run in order of priority, and given
65 * the opportunity to modify a value by returning a new value.
66 *
67 * The following example shows how a callback function is bound to a filter hook.
68 *
69 * Note that `$example` is passed to the callback, (maybe) modified, then returned:
70 *
71 * function example_callback( $example ) {
72 * // Maybe modify $example in some way.
73 * return $example;
74 * }
75 * add_filter( 'example_filter', 'example_callback' );
76 *
77 * Bound callbacks can accept from none to the total number of arguments passed as parameters
78 * in the corresponding apply_filters() call.
79 *
80 * In other words, if an apply_filters() call passes four total arguments, callbacks bound to
81 * it can accept none (the same as 1) of the arguments or up to four. The important part is that
82 * the `$accepted_args` value must reflect the number of arguments the bound callback *actually*
83 * opted to accept. If no arguments were accepted by the callback that is considered to be the
84 * same as accepting 1 argument. For example:
85 *
86 * // Filter call.
87 * $value = apply_filters( 'hook', $value, $arg2, $arg3 );
88 *
89 * // Accepting zero/one arguments.
90 * function example_callback() {
91 * ...
92 * return 'some value';
93 * }
94 * add_filter( 'hook', 'example_callback' ); // Where $priority is default 10, $accepted_args is default 1.
95 *
96 * // Accepting two arguments (three possible).
97 * function example_callback( $value, $arg2 ) {
98 * ...
99 * return $maybe_modified_value;
100 * }
101 * add_filter( 'hook', 'example_callback', 10, 2 ); // Where $priority is 10, $accepted_args is 2.
102 *
103 * *Note:* The function will return true whether or not the callback is valid.
104 * It is up to you to take care. This is done for optimization purposes, so
105 * everything is as quick as possible.
106 *
107 * @since 0.71
108 *
109 * @global WP_Hook[] $wp_filter A multidimensional array of all hooks and the callbacks hooked to them.
110 *
111 * @param string $hook_name The name of the filter to add the callback to.
112 * @param callable $callback The callback to be run when the filter is applied.
113 * @param int $priority Optional. Used to specify the order in which the functions
114 * associated with a particular filter are executed.
115 * Lower numbers correspond with earlier execution,
116 * and functions with the same priority are executed
117 * in the order in which they were added to the filter. Default 10.
118 * @param int $accepted_args Optional. The number of arguments the function accepts. Default 1.
119 * @return true Always returns true.
120 */
121function add_filter( $hook_name, $callback, $priority = 10, $accepted_args = 1 ) {
122 global $wp_filter;
123
124 if ( ! isset( $wp_filter[ $hook_name ] ) ) {
125 $wp_filter[ $hook_name ] = new WP_Hook();
126 }
127
128 $wp_filter[ $hook_name ]->add_filter( $hook_name, $callback, $priority, $accepted_args );
129
130 return true;
131}
132
133/**
134 * Calls the callback functions that have been added to a filter hook.
135 *
136 * This function invokes all functions attached to filter hook `$hook_name`.
137 * It is possible to create new filter hooks by simply calling this function,
138 * specifying the name of the new hook using the `$hook_name` parameter.
139 *
140 * The function also allows for multiple additional arguments to be passed to hooks.
141 *
142 * Example usage:
143 *
144 * // The filter callback function.
145 * function example_callback( $string, $arg1, $arg2 ) {
146 * // (maybe) modify $string.
147 * return $string;
148 * }
149 * add_filter( 'example_filter', 'example_callback', 10, 3 );
150 *
151 * /*
152 * * Apply the filters by calling the 'example_callback()' function
153 * * that's hooked onto `example_filter` above.
154 * *
155 * * - 'example_filter' is the filter hook.
156 * * - 'filter me' is the value being filtered.
157 * * - $arg1 and $arg2 are the additional arguments passed to the callback.
158 * $value = apply_filters( 'example_filter', 'filter me', $arg1, $arg2 );
159 *
160 * @since 0.71
161 * @since 6.0.0 Formalized the existing and already documented `...$args` parameter
162 * by adding it to the function signature.
163 *
164 * @global WP_Hook[] $wp_filter Stores all of the filters and actions.
165 * @global int[] $wp_filters Stores the number of times each filter was triggered.
166 * @global string[] $wp_current_filter Stores the list of current filters with the current one last.
167 *
168 * @param string $hook_name The name of the filter hook.
169 * @param mixed $value The value to filter.
170 * @param mixed ...$args Optional. Additional parameters to pass to the callback functions.
171 * @return mixed The filtered value after all hooked functions are applied to it.
172 */
173function apply_filters( $hook_name, $value, ...$args ) {
174 global $wp_filter, $wp_filters, $wp_current_filter;
175
176 if ( ! isset( $wp_filters[ $hook_name ] ) ) {
177 $wp_filters[ $hook_name ] = 1;
178 } else {
179 ++$wp_filters[ $hook_name ];
180 }
181
182 // Do 'all' actions first.
183 if ( isset( $wp_filter['all'] ) ) {
184 $wp_current_filter[] = $hook_name;
185
186 $all_args = func_get_args(); // phpcs:ignore PHPCompatibility.FunctionUse.ArgumentFunctionsReportCurrentValue.NeedsInspection
187 _wp_call_all_hook( $all_args );
188 }
189
190 if ( ! isset( $wp_filter[ $hook_name ] ) ) {
191 if ( isset( $wp_filter['all'] ) ) {
192 array_pop( $wp_current_filter );
193 }
194
195 return $value;
196 }
197
198 if ( ! isset( $wp_filter['all'] ) ) {
199 $wp_current_filter[] = $hook_name;
200 }
201
202 // Pass the value to WP_Hook.
203 array_unshift( $args, $value );
204
205 $filtered = $wp_filter[ $hook_name ]->apply_filters( $value, $args );
206
207 array_pop( $wp_current_filter );
208
209 return $filtered;
210}
211
212/**
213 * Calls the callback functions that have been added to a filter hook, specifying arguments in an array.
214 *
215 * @since 3.0.0
216 *
217 * @see apply_filters() This function is identical, but the arguments passed to the
218 * functions hooked to `$hook_name` are supplied using an array.
219 *
220 * @global WP_Hook[] $wp_filter Stores all of the filters and actions.
221 * @global int[] $wp_filters Stores the number of times each filter was triggered.
222 * @global string[] $wp_current_filter Stores the list of current filters with the current one last.
223 *
224 * @param string $hook_name The name of the filter hook.
225 * @param array $args The arguments supplied to the functions hooked to `$hook_name`.
226 * @return mixed The filtered value after all hooked functions are applied to it.
227 */
228function apply_filters_ref_array( $hook_name, $args ) {
229 global $wp_filter, $wp_filters, $wp_current_filter;
230
231 if ( ! isset( $wp_filters[ $hook_name ] ) ) {
232 $wp_filters[ $hook_name ] = 1;
233 } else {
234 ++$wp_filters[ $hook_name ];
235 }
236
237 // Do 'all' actions first.
238 if ( isset( $wp_filter['all'] ) ) {
239 $wp_current_filter[] = $hook_name;
240 $all_args = func_get_args(); // phpcs:ignore PHPCompatibility.FunctionUse.ArgumentFunctionsReportCurrentValue.NeedsInspection
241 _wp_call_all_hook( $all_args );
242 }
243
244 if ( ! isset( $wp_filter[ $hook_name ] ) ) {
245 if ( isset( $wp_filter['all'] ) ) {
246 array_pop( $wp_current_filter );
247 }
248
249 return $args[0];
250 }
251
252 if ( ! isset( $wp_filter['all'] ) ) {
253 $wp_current_filter[] = $hook_name;
254 }
255
256 $filtered = $wp_filter[ $hook_name ]->apply_filters( $args[0], $args );
257
258 array_pop( $wp_current_filter );
259
260 return $filtered;
261}
262
263/**
264 * Checks if any filter has been registered for a hook.
265 *
266 * When using the `$callback` argument, this function may return a non-boolean value
267 * that evaluates to false (e.g. 0), so use the `===` operator for testing the return value.
268 *
269 * @since 2.5.0
270 * @since 6.9.0 Added the `$priority` parameter.
271 *
272 * @global WP_Hook[] $wp_filter Stores all of the filters and actions.
273 *
274 * @param string $hook_name The name of the filter hook.
275 * @param callable|string|array|false $callback Optional. The callback to check for.
276 * This function can be called unconditionally to speculatively check
277 * a callback that may or may not exist. Default false.
278 * @param int|false $priority Optional. The specific priority at which to check for the callback.
279 * Default false.
280 * @return bool|int If `$callback` is omitted, returns boolean for whether the hook has
281 * anything registered. When checking a specific function, the priority
282 * of that hook is returned, or false if the function is not attached.
283 * If `$callback` and `$priority` are both provided, a boolean is returned
284 * for whether the specific function is registered at that priority.
285 */
286function has_filter( $hook_name, $callback = false, $priority = false ) {
287 global $wp_filter;
288
289 if ( ! isset( $wp_filter[ $hook_name ] ) ) {
290 return false;
291 }
292
293 return $wp_filter[ $hook_name ]->has_filter( $hook_name, $callback, $priority );
294}
295
296/**
297 * Removes a callback function from a filter hook.
298 *
299 * This can be used to remove default functions attached to a specific filter
300 * hook and possibly replace them with a substitute.
301 *
302 * To remove a hook, the `$callback` and `$priority` arguments must match
303 * when the hook was added. This goes for both filters and actions. No warning
304 * will be given on removal failure.
305 *
306 * @since 1.2.0
307 *
308 * @global WP_Hook[] $wp_filter Stores all of the filters and actions.
309 *
310 * @param string $hook_name The filter hook to which the function to be removed is hooked.
311 * @param callable|string|array $callback The callback to be removed from running when the filter is applied.
312 * This function can be called unconditionally to speculatively remove
313 * a callback that may or may not exist.
314 * @param int $priority Optional. The exact priority used when adding the original
315 * filter callback. Default 10.
316 * @return bool Whether the function existed before it was removed.
317 */
318function remove_filter( $hook_name, $callback, $priority = 10 ) {
319 global $wp_filter;
320
321 $r = false;
322
323 if ( isset( $wp_filter[ $hook_name ] ) ) {
324 $r = $wp_filter[ $hook_name ]->remove_filter( $hook_name, $callback, $priority );
325
326 if ( ! $wp_filter[ $hook_name ]->callbacks ) {
327 unset( $wp_filter[ $hook_name ] );
328 }
329 }
330
331 return $r;
332}
333
334/**
335 * Removes all of the callback functions from a filter hook.
336 *
337 * @since 2.7.0
338 *
339 * @global WP_Hook[] $wp_filter Stores all of the filters and actions.
340 *
341 * @param string $hook_name The filter to remove callbacks from.
342 * @param int|false $priority Optional. The priority number to remove them from.
343 * Default false.
344 * @return true Always returns true.
345 */
346function remove_all_filters( $hook_name, $priority = false ) {
347 global $wp_filter;
348
349 if ( isset( $wp_filter[ $hook_name ] ) ) {
350 $wp_filter[ $hook_name ]->remove_all_filters( $priority );
351
352 if ( ! $wp_filter[ $hook_name ]->has_filters() ) {
353 unset( $wp_filter[ $hook_name ] );
354 }
355 }
356
357 return true;
358}
359
360/**
361 * Retrieves the name of the current filter hook.
362 *
363 * @since 2.5.0
364 *
365 * @global string[] $wp_current_filter Stores the list of current filters with the current one last
366 *
367 * @return string|false Hook name of the current filter, false if no filter is running.
368 */
369function current_filter() {
370 global $wp_current_filter;
371
372 return end( $wp_current_filter );
373}
374
375/**
376 * Returns whether or not a filter hook is currently being processed.
377 *
378 * The function current_filter() only returns the most recent filter being executed.
379 * did_filter() returns the number of times a filter has been applied during
380 * the current request.
381 *
382 * This function allows detection for any filter currently being executed
383 * (regardless of whether it's the most recent filter to fire, in the case of
384 * hooks called from hook callbacks) to be verified.
385 *
386 * @since 3.9.0
387 *
388 * @see current_filter()
389 * @see did_filter()
390 * @global string[] $wp_current_filter Current filter.
391 *
392 * @param string|null $hook_name Optional. Filter hook to check. Defaults to null,
393 * which checks if any filter is currently being run.
394 * @return bool Whether the filter is currently in the stack.
395 */
396function doing_filter( $hook_name = null ) {
397 global $wp_current_filter;
398
399 if ( null === $hook_name ) {
400 return ! empty( $wp_current_filter );
401 }
402
403 return in_array( $hook_name, $wp_current_filter, true );
404}
405
406/**
407 * Retrieves the number of times a filter has been applied during the current request.
408 *
409 * @since 6.1.0
410 *
411 * @global int[] $wp_filters Stores the number of times each filter was triggered.
412 *
413 * @param string $hook_name The name of the filter hook.
414 * @return int The number of times the filter hook has been applied.
415 */
416function did_filter( $hook_name ) {
417 global $wp_filters;
418
419 if ( ! isset( $wp_filters[ $hook_name ] ) ) {
420 return 0;
421 }
422
423 return $wp_filters[ $hook_name ];
424}
425
426/**
427 * Adds a callback function to an action hook.
428 *
429 * Actions are the hooks that the WordPress core launches at specific points
430 * during execution, or when specific events occur. Plugins can specify that
431 * one or more of its PHP functions are executed at these points, using the
432 * Action API.
433 *
434 * @since 1.2.0
435 *
436 * @param string $hook_name The name of the action to add the callback to.
437 * @param callable $callback The callback to be run when the action is called.
438 * @param int $priority Optional. Used to specify the order in which the functions
439 * associated with a particular action are executed.
440 * Lower numbers correspond with earlier execution,
441 * and functions with the same priority are executed
442 * in the order in which they were added to the action. Default 10.
443 * @param int $accepted_args Optional. The number of arguments the function accepts. Default 1.
444 * @return true Always returns true.
445 */
446function add_action( $hook_name, $callback, $priority = 10, $accepted_args = 1 ) {
447 return add_filter( $hook_name, $callback, $priority, $accepted_args );
448}
449
450/**
451 * Calls the callback functions that have been added to an action hook.
452 *
453 * This function invokes all functions attached to action hook `$hook_name`.
454 * It is possible to create new action hooks by simply calling this function,
455 * specifying the name of the new hook using the `$hook_name` parameter.
456 *
457 * You can pass extra arguments to the hooks, much like you can with `apply_filters()`.
458 *
459 * Example usage:
460 *
461 * // The action callback function.
462 * function example_callback( $arg1, $arg2 ) {
463 * // (maybe) do something with the args.
464 * }
465 * add_action( 'example_action', 'example_callback', 10, 2 );
466 *
467 * /*
468 * * Trigger the actions by calling the 'example_callback()' function
469 * * that's hooked onto `example_action` above.
470 * *
471 * * - 'example_action' is the action hook.
472 * * - $arg1 and $arg2 are the additional arguments passed to the callback.
473 * do_action( 'example_action', $arg1, $arg2 );
474 *
475 * @since 1.2.0
476 * @since 5.3.0 Formalized the existing and already documented `...$arg` parameter
477 * by adding it to the function signature.
478 *
479 * @global WP_Hook[] $wp_filter Stores all of the filters and actions.
480 * @global int[] $wp_actions Stores the number of times each action was triggered.
481 * @global string[] $wp_current_filter Stores the list of current filters with the current one last.
482 *
483 * @param string $hook_name The name of the action to be executed.
484 * @param mixed ...$arg Optional. Additional arguments which are passed on to the
485 * functions hooked to the action. Default empty.
486 */
487function do_action( $hook_name, ...$arg ) {
488 global $wp_filter, $wp_actions, $wp_current_filter;
489
490 if ( ! isset( $wp_actions[ $hook_name ] ) ) {
491 $wp_actions[ $hook_name ] = 1;
492 } else {
493 ++$wp_actions[ $hook_name ];
494 }
495
496 // Do 'all' actions first.
497 if ( isset( $wp_filter['all'] ) ) {
498 $wp_current_filter[] = $hook_name;
499 $all_args = func_get_args(); // phpcs:ignore PHPCompatibility.FunctionUse.ArgumentFunctionsReportCurrentValue.NeedsInspection
500 _wp_call_all_hook( $all_args );
501 }
502
503 if ( ! isset( $wp_filter[ $hook_name ] ) ) {
504 if ( isset( $wp_filter['all'] ) ) {
505 array_pop( $wp_current_filter );
506 }
507
508 return;
509 }
510
511 if ( ! isset( $wp_filter['all'] ) ) {
512 $wp_current_filter[] = $hook_name;
513 }
514
515 if ( empty( $arg ) ) {
516 $arg[] = '';
517 } elseif ( is_array( $arg[0] ) && 1 === count( $arg[0] ) && isset( $arg[0][0] ) && is_object( $arg[0][0] ) ) {
518 // Backward compatibility for PHP4-style passing of `array( &$this )` as action `$arg`.
519 $arg[0] = $arg[0][0];
520 }
521
522 $wp_filter[ $hook_name ]->do_action( $arg );
523
524 array_pop( $wp_current_filter );
525}
526
527/**
528 * Calls the callback functions that have been added to an action hook, specifying arguments in an array.
529 *
530 * @since 2.1.0
531 *
532 * @see do_action() This function is identical, but the arguments passed to the
533 * functions hooked to `$hook_name` are supplied using an array.
534 *
535 * @global WP_Hook[] $wp_filter Stores all of the filters and actions.
536 * @global int[] $wp_actions Stores the number of times each action was triggered.
537 * @global string[] $wp_current_filter Stores the list of current filters with the current one last.
538 *
539 * @param string $hook_name The name of the action to be executed.
540 * @param array $args The arguments supplied to the functions hooked to `$hook_name`.
541 */
542function do_action_ref_array( $hook_name, $args ) {
543 global $wp_filter, $wp_actions, $wp_current_filter;
544
545 if ( ! isset( $wp_actions[ $hook_name ] ) ) {
546 $wp_actions[ $hook_name ] = 1;
547 } else {
548 ++$wp_actions[ $hook_name ];
549 }
550
551 // Do 'all' actions first.
552 if ( isset( $wp_filter['all'] ) ) {
553 $wp_current_filter[] = $hook_name;
554 $all_args = func_get_args(); // phpcs:ignore PHPCompatibility.FunctionUse.ArgumentFunctionsReportCurrentValue.NeedsInspection
555 _wp_call_all_hook( $all_args );
556 }
557
558 if ( ! isset( $wp_filter[ $hook_name ] ) ) {
559 if ( isset( $wp_filter['all'] ) ) {
560 array_pop( $wp_current_filter );
561 }
562
563 return;
564 }
565
566 if ( ! isset( $wp_filter['all'] ) ) {
567 $wp_current_filter[] = $hook_name;
568 }
569
570 $wp_filter[ $hook_name ]->do_action( $args );
571
572 array_pop( $wp_current_filter );
573}
574
575/**
576 * Checks if any action has been registered for a hook.
577 *
578 * When using the `$callback` argument, this function may return a non-boolean value
579 * that evaluates to false (e.g. 0), so use the `===` operator for testing the return value.
580 *
581 * @since 2.5.0
582 * @since 6.9.0 Added the `$priority` parameter.
583 *
584 * @see has_filter() This function is an alias of has_filter().
585 *
586 * @param string $hook_name The name of the action hook.
587 * @param callable|string|array|false $callback Optional. The callback to check for.
588 * This function can be called unconditionally to speculatively check
589 * a callback that may or may not exist. Default false.
590 * @param int|false $priority Optional. The specific priority at which to check for the callback.
591 * Default false.
592 * @return bool|int If `$callback` is omitted, returns boolean for whether the hook has
593 * anything registered. When checking a specific function, the priority
594 * of that hook is returned, or false if the function is not attached.
595 * If `$callback` and `$priority` are both provided, a boolean is returned
596 * for whether the specific function is registered at that priority.
597 */
598function has_action( $hook_name, $callback = false, $priority = false ) {
599 return has_filter( $hook_name, $callback, $priority );
600}
601
602/**
603 * Removes a callback function from an action hook.
604 *
605 * This can be used to remove default functions attached to a specific action
606 * hook and possibly replace them with a substitute.
607 *
608 * To remove a hook, the `$callback` and `$priority` arguments must match
609 * when the hook was added. This goes for both filters and actions. No warning
610 * will be given on removal failure.
611 *
612 * @since 1.2.0
613 *
614 * @param string $hook_name The action hook to which the function to be removed is hooked.
615 * @param callable|string|array $callback The name of the function which should be removed.
616 * This function can be called unconditionally to speculatively remove
617 * a callback that may or may not exist.
618 * @param int $priority Optional. The exact priority used when adding the original
619 * action callback. Default 10.
620 * @return bool Whether the function is removed.
621 */
622function remove_action( $hook_name, $callback, $priority = 10 ) {
623 return remove_filter( $hook_name, $callback, $priority );
624}
625
626/**
627 * Removes all of the callback functions from an action hook.
628 *
629 * @since 2.7.0
630 *
631 * @param string $hook_name The action to remove callbacks from.
632 * @param int|false $priority Optional. The priority number to remove them from.
633 * Default false.
634 * @return true Always returns true.
635 */
636function remove_all_actions( $hook_name, $priority = false ) {
637 return remove_all_filters( $hook_name, $priority );
638}
639
640/**
641 * Retrieves the name of the current action hook.
642 *
643 * @since 3.9.0
644 *
645 * @return string|false Hook name of the current action, false if no action is running.
646 */
647function current_action() {
648 return current_filter();
649}
650
651/**
652 * Returns whether or not an action hook is currently being processed.
653 *
654 * The function current_action() only returns the most recent action being executed.
655 * did_action() returns the number of times an action has been fired during
656 * the current request.
657 *
658 * This function allows detection for any action currently being executed
659 * (regardless of whether it's the most recent action to fire, in the case of
660 * hooks called from hook callbacks) to be verified.
661 *
662 * @since 3.9.0
663 *
664 * @see current_action()
665 * @see did_action()
666 *
667 * @param string|null $hook_name Optional. Action hook to check. Defaults to null,
668 * which checks if any action is currently being run.
669 * @return bool Whether the action is currently in the stack.
670 */
671function doing_action( $hook_name = null ) {
672 return doing_filter( $hook_name );
673}
674
675/**
676 * Retrieves the number of times an action has been fired during the current request.
677 *
678 * @since 2.1.0
679 *
680 * @global int[] $wp_actions Stores the number of times each action was triggered.
681 *
682 * @param string $hook_name The name of the action hook.
683 * @return int The number of times the action hook has been fired.
684 */
685function did_action( $hook_name ) {
686 global $wp_actions;
687
688 if ( ! isset( $wp_actions[ $hook_name ] ) ) {
689 return 0;
690 }
691
692 return $wp_actions[ $hook_name ];
693}
694
695/**
696 * Fires functions attached to a deprecated filter hook.
697 *
698 * When a filter hook is deprecated, the apply_filters() call is replaced with
699 * apply_filters_deprecated(), which triggers a deprecation notice and then fires
700 * the original filter hook.
701 *
702 * Note: the value and extra arguments passed to the original apply_filters() call
703 * must be passed here to `$args` as an array. For example:
704 *
705 * // Old filter.
706 * return apply_filters( 'wpdocs_filter', $value, $extra_arg );
707 *
708 * // Deprecated.
709 * return apply_filters_deprecated( 'wpdocs_filter', array( $value, $extra_arg ), '4.9.0', 'wpdocs_new_filter' );
710 *
711 * @since 4.6.0
712 *
713 * @see _deprecated_hook()
714 *
715 * @param string $hook_name The name of the filter hook.
716 * @param array $args Array of additional function arguments to be passed to apply_filters().
717 * @param string $version The version of WordPress that deprecated the hook.
718 * @param string $replacement Optional. The hook that should have been used. Default empty.
719 * @param string $message Optional. A message regarding the change. Default empty.
720 * @return mixed The filtered value after all hooked functions are applied to it.
721 */
722function apply_filters_deprecated( $hook_name, $args, $version, $replacement = '', $message = '' ) {
723 if ( ! has_filter( $hook_name ) ) {
724 return $args[0];
725 }
726
727 _deprecated_hook( $hook_name, $version, $replacement, $message );
728
729 return apply_filters_ref_array( $hook_name, $args );
730}
731
732/**
733 * Fires functions attached to a deprecated action hook.
734 *
735 * When an action hook is deprecated, the do_action() call is replaced with
736 * do_action_deprecated(), which triggers a deprecation notice and then fires
737 * the original hook.
738 *
739 * @since 4.6.0
740 *
741 * @see _deprecated_hook()
742 *
743 * @param string $hook_name The name of the action hook.
744 * @param array $args Array of additional function arguments to be passed to do_action().
745 * @param string $version The version of WordPress that deprecated the hook.
746 * @param string $replacement Optional. The hook that should have been used. Default empty.
747 * @param string $message Optional. A message regarding the change. Default empty.
748 */
749function do_action_deprecated( $hook_name, $args, $version, $replacement = '', $message = '' ) {
750 if ( ! has_action( $hook_name ) ) {
751 return;
752 }
753
754 _deprecated_hook( $hook_name, $version, $replacement, $message );
755
756 do_action_ref_array( $hook_name, $args );
757}
758
759//
760// Functions for handling plugins.
761//
762
763/**
764 * Gets the basename of a plugin.
765 *
766 * This method extracts the name of a plugin from its filename.
767 *
768 * @since 1.5.0
769 *
770 * @global array $wp_plugin_paths
771 *
772 * @param string $file The filename of plugin.
773 * @return string The name of a plugin.
774 */
775function plugin_basename( $file ) {
776 global $wp_plugin_paths;
777
778 // $wp_plugin_paths contains normalized paths.
779 $file = wp_normalize_path( $file );
780
781 arsort( $wp_plugin_paths );
782
783 foreach ( $wp_plugin_paths as $dir => $realdir ) {
784 if ( str_starts_with( $file, $realdir ) ) {
785 $file = $dir . substr( $file, strlen( $realdir ) );
786 }
787 }
788
789 $plugin_dir = wp_normalize_path( WP_PLUGIN_DIR );
790 $mu_plugin_dir = wp_normalize_path( WPMU_PLUGIN_DIR );
791
792 // Get relative path from plugins directory.
793 $file = preg_replace( '#^' . preg_quote( $plugin_dir, '#' ) . '/|^' . preg_quote( $mu_plugin_dir, '#' ) . '/#', '', $file );
794 $file = trim( $file, '/' );
795 return $file;
796}
797
798/**
799 * Register a plugin's real path.
800 *
801 * This is used in plugin_basename() to resolve symlinked paths.
802 *
803 * @since 3.9.0
804 *
805 * @see wp_normalize_path()
806 *
807 * @global array $wp_plugin_paths
808 *
809 * @param string $file Known path to the file.
810 * @return bool Whether the path was able to be registered.
811 */
812function wp_register_plugin_realpath( $file ) {
813 global $wp_plugin_paths;
814
815 // Normalize, but store as static to avoid recalculation of a constant value.
816 static $wp_plugin_path = null, $wpmu_plugin_path = null;
817
818 if ( ! isset( $wp_plugin_path ) ) {
819 $wp_plugin_path = wp_normalize_path( WP_PLUGIN_DIR );
820 $wpmu_plugin_path = wp_normalize_path( WPMU_PLUGIN_DIR );
821 }
822
823 $plugin_path = wp_normalize_path( dirname( $file ) );
824 $plugin_realpath = wp_normalize_path( dirname( realpath( $file ) ) );
825
826 if ( $plugin_path === $wp_plugin_path || $plugin_path === $wpmu_plugin_path ) {
827 return false;
828 }
829
830 if ( $plugin_path !== $plugin_realpath ) {
831 $wp_plugin_paths[ $plugin_path ] = $plugin_realpath;
832 }
833
834 return true;
835}
836
837/**
838 * Get the filesystem directory path (with trailing slash) for the plugin __FILE__ passed in.
839 *
840 * @since 2.8.0
841 *
842 * @param string $file The filename of the plugin (__FILE__).
843 * @return string the filesystem path of the directory that contains the plugin.
844 */
845function plugin_dir_path( $file ) {
846 return trailingslashit( dirname( $file ) );
847}
848
849/**
850 * Get the URL directory path (with trailing slash) for the plugin __FILE__ passed in.
851 *
852 * @since 2.8.0
853 *
854 * @param string $file The filename of the plugin (__FILE__).
855 * @return string the URL path of the directory that contains the plugin.
856 */
857function plugin_dir_url( $file ) {
858 return trailingslashit( plugins_url( '', $file ) );
859}
860
861/**
862 * Set the activation hook for a plugin.
863 *
864 * When a plugin is activated, the action 'activate_PLUGINNAME' hook is
865 * called. In the name of this hook, PLUGINNAME is replaced with the name
866 * of the plugin, including the optional subdirectory. For example, when the
867 * plugin is located in wp-content/plugins/sampleplugin/sample.php, then
868 * the name of this hook will become 'activate_sampleplugin/sample.php'.
869 *
870 * When the plugin consists of only one file and is (as by default) located at
871 * wp-content/plugins/sample.php the name of this hook will be
872 * 'activate_sample.php'.
873 *
874 * @since 2.0.0
875 *
876 * @param string $file The filename of the plugin including the path.
877 * @param callable $callback The function hooked to the 'activate_PLUGIN' action.
878 */
879function register_activation_hook( $file, $callback ) {
880 $file = plugin_basename( $file );
881 add_action( 'activate_' . $file, $callback );
882}
883
884/**
885 * Sets the deactivation hook for a plugin.
886 *
887 * When a plugin is deactivated, the action 'deactivate_PLUGINNAME' hook is
888 * called. In the name of this hook, PLUGINNAME is replaced with the name
889 * of the plugin, including the optional subdirectory. For example, when the
890 * plugin is located in wp-content/plugins/sampleplugin/sample.php, then
891 * the name of this hook will become 'deactivate_sampleplugin/sample.php'.
892 *
893 * When the plugin consists of only one file and is (as by default) located at
894 * wp-content/plugins/sample.php the name of this hook will be
895 * 'deactivate_sample.php'.
896 *
897 * @since 2.0.0
898 *
899 * @param string $file The filename of the plugin including the path.
900 * @param callable $callback The function hooked to the 'deactivate_PLUGIN' action.
901 */
902function register_deactivation_hook( $file, $callback ) {
903 $file = plugin_basename( $file );
904 add_action( 'deactivate_' . $file, $callback );
905}
906
907/**
908 * Sets the uninstallation hook for a plugin.
909 *
910 * Registers the uninstall hook that will be called when the user clicks on the
911 * uninstall link that calls for the plugin to uninstall itself. The link won't
912 * be active unless the plugin hooks into the action.
913 *
914 * The plugin should not run arbitrary code outside of functions, when
915 * registering the uninstall hook. In order to run using the hook, the plugin
916 * will have to be included, which means that any code laying outside of a
917 * function will be run during the uninstallation process. The plugin should not
918 * hinder the uninstallation process.
919 *
920 * If the plugin can not be written without running code within the plugin, then
921 * the plugin should create a file named 'uninstall.php' in the base plugin
922 * folder. This file will be called, if it exists, during the uninstallation process
923 * bypassing the uninstall hook. The plugin, when using the 'uninstall.php'
924 * should always check for the 'WP_UNINSTALL_PLUGIN' constant, before
925 * executing.
926 *
927 * @since 2.7.0
928 *
929 * @param string $file Plugin file.
930 * @param callable $callback The callback to run when the hook is called. Must be
931 * a static method or function.
932 */
933function register_uninstall_hook( $file, $callback ) {
934 if ( is_array( $callback ) && is_object( $callback[0] ) ) {
935 _doing_it_wrong( __FUNCTION__, __( 'Only a static class method or function can be used in an uninstall hook.' ), '3.1.0' );
936 return;
937 }
938
939 /*
940 * The option should not be autoloaded, because it is not needed in most
941 * cases. Emphasis should be put on using the 'uninstall.php' way of
942 * uninstalling the plugin.
943 */
944 $uninstallable_plugins = (array) get_option( 'uninstall_plugins' );
945 $plugin_basename = plugin_basename( $file );
946
947 if ( ! isset( $uninstallable_plugins[ $plugin_basename ] ) || $uninstallable_plugins[ $plugin_basename ] !== $callback ) {
948 $uninstallable_plugins[ $plugin_basename ] = $callback;
949 update_option( 'uninstall_plugins', $uninstallable_plugins );
950 }
951}
952
953/**
954 * Calls the 'all' hook, which will process the functions hooked into it.
955 *
956 * The 'all' hook passes all of the arguments or parameters that were used for
957 * the hook, which this function was called for.
958 *
959 * This function is used internally for apply_filters(), do_action(), and
960 * do_action_ref_array() and is not meant to be used from outside those
961 * functions. This function does not check for the existence of the all hook, so
962 * it will fail unless the all hook exists prior to this function call.
963 *
964 * @since 2.5.0
965 * @access private
966 *
967 * @global WP_Hook[] $wp_filter Stores all of the filters and actions.
968 *
969 * @param array $args The collected parameters from the hook that was called.
970 */
971function _wp_call_all_hook( $args ) {
972 global $wp_filter;
973
974 $wp_filter['all']->do_all_hook( $args );
975}
976
977/**
978 * Builds a unique string ID for a hook callback function.
979 *
980 * Functions and static method callbacks are just returned as strings and
981 * shouldn't have any speed penalty.
982 *
983 * @link https://core.trac.wordpress.org/ticket/3875
984 *
985 * @since 2.2.3
986 * @since 5.3.0 Removed workarounds for spl_object_hash().
987 * `$hook_name` and `$priority` are no longer used,
988 * and the function always returns a string.
989 *
990 * @access private
991 *
992 * @param string $hook_name Unused. The name of the filter to build ID for.
993 * @param callable|string|array $callback The callback to generate ID for. The callback may
994 * or may not exist.
995 * @param int $priority Unused. The order in which the functions
996 * associated with a particular action are executed.
997 * @return string|null Unique function ID for usage as array key.
998 * Null if a valid `$callback` is not passed.
999 */
1000function _wp_filter_build_unique_id( $hook_name, $callback, $priority ) {
1001 if ( is_string( $callback ) ) {
1002 return $callback;
1003 }
1004
1005 if ( is_object( $callback ) ) {
1006 // Closures are currently implemented as objects.
1007 $callback = array( $callback, '' );
1008 } else {
1009 $callback = (array) $callback;
1010 }
1011
1012 if ( is_object( $callback[0] ) ) {
1013 // Object class calling.
1014 return spl_object_hash( $callback[0] ) . $callback[1];
1015 } elseif ( is_string( $callback[0] ) ) {
1016 // Static calling.
1017 return $callback[0] . '::' . $callback[1];
1018 }
1019
1020 return null;
1021}
1022