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aaf99e6 Dec 1, 2017
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<?php
/**
* The plugin API is located in this file, which allows for creating actions
* and filters and hooking functions, and methods. The functions or methods will
* then be run when the action or filter is called.
*
* The API callback examples reference functions, but can be methods of classes.
* To hook methods, you'll need to pass an array one of two ways.
*
* Any of the syntaxes explained in the PHP documentation for the
* {@link https://secure.php.net/manual/en/language.pseudo-types.php#language.types.callback 'callback'}
* type are valid.
*
* Also see the {@link https://codex.wordpress.org/Plugin_API Plugin API} for
* more information and examples on how to use a lot of these functions.
*
* This file should have no external dependencies.
*
* @package WordPress
* @subpackage Plugin
* @since 1.5.0
*/
// Initialize the filter globals.
require( dirname( __FILE__ ) . '/class-wp-hook.php' );
/** @var WP_Hook[] $wp_filter */
global $wp_filter, $wp_actions, $wp_current_filter;
if ( $wp_filter ) {
$wp_filter = WP_Hook::build_preinitialized_hooks( $wp_filter );
} else {
$wp_filter = array();
}
if ( ! isset( $wp_actions ) ) {
$wp_actions = array();
}
if ( ! isset( $wp_current_filter ) ) {
$wp_current_filter = array();
}
/**
* Hook a function or method to a specific filter action.
*
* WordPress offers filter hooks to allow plugins to modify
* various types of internal data at runtime.
*
* A plugin can modify data by binding a callback to a filter hook. When the filter
* is later applied, each bound callback is run in order of priority, and given
* the opportunity to modify a value by returning a new value.
*
* The following example shows how a callback function is bound to a filter hook.
*
* Note that `$example` is passed to the callback, (maybe) modified, then returned:
*
* function example_callback( $example ) {
* // Maybe modify $example in some way.
* return $example;
* }
* add_filter( 'example_filter', 'example_callback' );
*
* Bound callbacks can accept from none to the total number of arguments passed as parameters
* in the corresponding apply_filters() call.
*
* In other words, if an apply_filters() call passes four total arguments, callbacks bound to
* it can accept none (the same as 1) of the arguments or up to four. The important part is that
* the `$accepted_args` value must reflect the number of arguments the bound callback *actually*
* opted to accept. If no arguments were accepted by the callback that is considered to be the
* same as accepting 1 argument. For example:
*
* // Filter call.
* $value = apply_filters( 'hook', $value, $arg2, $arg3 );
*
* // Accepting zero/one arguments.
* function example_callback() {
* ...
* return 'some value';
* }
* add_filter( 'hook', 'example_callback' ); // Where $priority is default 10, $accepted_args is default 1.
*
* // Accepting two arguments (three possible).
* function example_callback( $value, $arg2 ) {
* ...
* return $maybe_modified_value;
* }
* add_filter( 'hook', 'example_callback', 10, 2 ); // Where $priority is 10, $accepted_args is 2.
*
* *Note:* The function will return true whether or not the callback is valid.
* It is up to you to take care. This is done for optimization purposes, so
* everything is as quick as possible.
*
* @since 0.71
*
* @global array $wp_filter A multidimensional array of all hooks and the callbacks hooked to them.
*
* @param string $tag The name of the filter to hook the $function_to_add callback to.
* @param callable $function_to_add The callback to be run when the filter is applied.
* @param int $priority Optional. Used to specify the order in which the functions
* associated with a particular action are executed. Default 10.
* Lower numbers correspond with earlier execution,
* and functions with the same priority are executed
* in the order in which they were added to the action.
* @param int $accepted_args Optional. The number of arguments the function accepts. Default 1.
* @return true
*/
function add_filter( $tag, $function_to_add, $priority = 10, $accepted_args = 1 ) {
global $wp_filter;
if ( ! isset( $wp_filter[ $tag ] ) ) {
$wp_filter[ $tag ] = new WP_Hook();
}
$wp_filter[ $tag ]->add_filter( $tag, $function_to_add, $priority, $accepted_args );
return true;
}
/**
* Check if any filter has been registered for a hook.
*
* @since 2.5.0
*
* @global array $wp_filter Stores all of the filters.
*
* @param string $tag The name of the filter hook.
* @param callable|bool $function_to_check Optional. The callback to check for. Default false.
* @return false|int If $function_to_check is omitted, returns boolean for whether the hook has
* anything registered. When checking a specific function, the priority of that
* hook is returned, or false if the function is not attached. When using the
* $function_to_check argument, this function may return a non-boolean value
* that evaluates to false (e.g.) 0, so use the === operator for testing the
* return value.
*/
function has_filter( $tag, $function_to_check = false ) {
global $wp_filter;
if ( ! isset( $wp_filter[ $tag ] ) ) {
return false;
}
return $wp_filter[ $tag ]->has_filter( $tag, $function_to_check );
}
/**
* Call the functions added to a filter hook.
*
* The callback functions attached to filter hook $tag are invoked by calling
* this function. This function can be used to create a new filter hook by
* simply calling this function with the name of the new hook specified using
* the $tag parameter.
*
* The function allows for additional arguments to be added and passed to hooks.
*
* // Our filter callback function
* function example_callback( $string, $arg1, $arg2 ) {
* // (maybe) modify $string
* return $string;
* }
* add_filter( 'example_filter', 'example_callback', 10, 3 );
*
* /*
* * Apply the filters by calling the 'example_callback' function we
* * "hooked" to 'example_filter' using the add_filter() function above.
* * - 'example_filter' is the filter hook $tag
* * - 'filter me' is the value being filtered
* * - $arg1 and $arg2 are the additional arguments passed to the callback.
* $value = apply_filters( 'example_filter', 'filter me', $arg1, $arg2 );
*
* @since 0.71
*
* @global array $wp_filter Stores all of the filters.
* @global array $wp_current_filter Stores the list of current filters with the current one last.
*
* @param string $tag The name of the filter hook.
* @param mixed $value The value on which the filters hooked to `$tag` are applied on.
* @param mixed $var,... Additional variables passed to the functions hooked to `$tag`.
* @return mixed The filtered value after all hooked functions are applied to it.
*/
function apply_filters( $tag, $value ) {
global $wp_filter, $wp_current_filter;
$args = array();
// Do 'all' actions first.
if ( isset( $wp_filter['all'] ) ) {
$wp_current_filter[] = $tag;
$args = func_get_args();
_wp_call_all_hook( $args );
}
if ( ! isset( $wp_filter[ $tag ] ) ) {
if ( isset( $wp_filter['all'] ) ) {
array_pop( $wp_current_filter );
}
return $value;
}
if ( ! isset( $wp_filter['all'] ) ) {
$wp_current_filter[] = $tag;
}
if ( empty( $args ) ) {
$args = func_get_args();
}
// don't pass the tag name to WP_Hook
array_shift( $args );
$filtered = $wp_filter[ $tag ]->apply_filters( $value, $args );
array_pop( $wp_current_filter );
return $filtered;
}
/**
* Execute functions hooked on a specific filter hook, specifying arguments in an array.
*
* @since 3.0.0
*
* @see apply_filters() This function is identical, but the arguments passed to the
* functions hooked to `$tag` are supplied using an array.
*
* @global array $wp_filter Stores all of the filters
* @global array $wp_current_filter Stores the list of current filters with the current one last
*
* @param string $tag The name of the filter hook.
* @param array $args The arguments supplied to the functions hooked to $tag.
* @return mixed The filtered value after all hooked functions are applied to it.
*/
function apply_filters_ref_array( $tag, $args ) {
global $wp_filter, $wp_current_filter;
// Do 'all' actions first
if ( isset( $wp_filter['all'] ) ) {
$wp_current_filter[] = $tag;
$all_args = func_get_args();
_wp_call_all_hook( $all_args );
}
if ( ! isset( $wp_filter[ $tag ] ) ) {
if ( isset( $wp_filter['all'] ) ) {
array_pop( $wp_current_filter );
}
return $args[0];
}
if ( ! isset( $wp_filter['all'] ) ) {
$wp_current_filter[] = $tag;
}
$filtered = $wp_filter[ $tag ]->apply_filters( $args[0], $args );
array_pop( $wp_current_filter );
return $filtered;
}
/**
* Removes a function from a specified filter hook.
*
* This function removes a function attached to a specified filter hook. This
* method can be used to remove default functions attached to a specific filter
* hook and possibly replace them with a substitute.
*
* To remove a hook, the $function_to_remove and $priority arguments must match
* when the hook was added. This goes for both filters and actions. No warning
* will be given on removal failure.
*
* @since 1.2.0
*
* @global array $wp_filter Stores all of the filters
*
* @param string $tag The filter hook to which the function to be removed is hooked.
* @param callable $function_to_remove The name of the function which should be removed.
* @param int $priority Optional. The priority of the function. Default 10.
* @return bool Whether the function existed before it was removed.
*/
function remove_filter( $tag, $function_to_remove, $priority = 10 ) {
global $wp_filter;
$r = false;
if ( isset( $wp_filter[ $tag ] ) ) {
$r = $wp_filter[ $tag ]->remove_filter( $tag, $function_to_remove, $priority );
if ( ! $wp_filter[ $tag ]->callbacks ) {
unset( $wp_filter[ $tag ] );
}
}
return $r;
}
/**
* Remove all of the hooks from a filter.
*
* @since 2.7.0
*
* @global array $wp_filter Stores all of the filters
*
* @param string $tag The filter to remove hooks from.
* @param int|bool $priority Optional. The priority number to remove. Default false.
* @return true True when finished.
*/
function remove_all_filters( $tag, $priority = false ) {
global $wp_filter;
if ( isset( $wp_filter[ $tag ] ) ) {
$wp_filter[ $tag ]->remove_all_filters( $priority );
if ( ! $wp_filter[ $tag ]->has_filters() ) {
unset( $wp_filter[ $tag ] );
}
}
return true;
}
/**
* Retrieve the name of the current filter or action.
*
* @since 2.5.0
*
* @global array $wp_current_filter Stores the list of current filters with the current one last
*
* @return string Hook name of the current filter or action.
*/
function current_filter() {
global $wp_current_filter;
return end( $wp_current_filter );
}
/**
* Retrieve the name of the current action.
*
* @since 3.9.0
*
* @return string Hook name of the current action.
*/
function current_action() {
return current_filter();
}
/**
* Retrieve the name of a filter currently being processed.
*
* The function current_filter() only returns the most recent filter or action
* being executed. did_action() returns true once the action is initially
* processed.
*
* This function allows detection for any filter currently being
* executed (despite not being the most recent filter to fire, in the case of
* hooks called from hook callbacks) to be verified.
*
* @since 3.9.0
*
* @see current_filter()
* @see did_action()
* @global array $wp_current_filter Current filter.
*
* @param null|string $filter Optional. Filter to check. Defaults to null, which
* checks if any filter is currently being run.
* @return bool Whether the filter is currently in the stack.
*/
function doing_filter( $filter = null ) {
global $wp_current_filter;
if ( null === $filter ) {
return ! empty( $wp_current_filter );
}
return in_array( $filter, $wp_current_filter );
}
/**
* Retrieve the name of an action currently being processed.
*
* @since 3.9.0
*
* @param string|null $action Optional. Action to check. Defaults to null, which checks
* if any action is currently being run.
* @return bool Whether the action is currently in the stack.
*/
function doing_action( $action = null ) {
return doing_filter( $action );
}
/**
* Hooks a function on to a specific action.
*
* Actions are the hooks that the WordPress core launches at specific points
* during execution, or when specific events occur. Plugins can specify that
* one or more of its PHP functions are executed at these points, using the
* Action API.
*
* @since 1.2.0
*
* @param string $tag The name of the action to which the $function_to_add is hooked.
* @param callable $function_to_add The name of the function you wish to be called.
* @param int $priority Optional. Used to specify the order in which the functions
* associated with a particular action are executed. Default 10.
* Lower numbers correspond with earlier execution,
* and functions with the same priority are executed
* in the order in which they were added to the action.
* @param int $accepted_args Optional. The number of arguments the function accepts. Default 1.
* @return true Will always return true.
*/
function add_action( $tag, $function_to_add, $priority = 10, $accepted_args = 1 ) {
return add_filter( $tag, $function_to_add, $priority, $accepted_args );
}
/**
* Execute functions hooked on a specific action hook.
*
* This function invokes all functions attached to action hook `$tag`. It is
* possible to create new action hooks by simply calling this function,
* specifying the name of the new hook using the `$tag` parameter.
*
* You can pass extra arguments to the hooks, much like you can with apply_filters().
*
* @since 1.2.0
*
* @global array $wp_filter Stores all of the filters
* @global array $wp_actions Increments the amount of times action was triggered.
* @global array $wp_current_filter Stores the list of current filters with the current one last
*
* @param string $tag The name of the action to be executed.
* @param mixed $arg,... Optional. Additional arguments which are passed on to the
* functions hooked to the action. Default empty.
*/
function do_action( $tag, $arg = '' ) {
global $wp_filter, $wp_actions, $wp_current_filter;
if ( ! isset( $wp_actions[ $tag ] ) ) {
$wp_actions[ $tag ] = 1;
} else {
++$wp_actions[ $tag ];
}
// Do 'all' actions first
if ( isset( $wp_filter['all'] ) ) {
$wp_current_filter[] = $tag;
$all_args = func_get_args();
_wp_call_all_hook( $all_args );
}
if ( ! isset( $wp_filter[ $tag ] ) ) {
if ( isset( $wp_filter['all'] ) ) {
array_pop( $wp_current_filter );
}
return;
}
if ( ! isset( $wp_filter['all'] ) ) {
$wp_current_filter[] = $tag;
}
$args = array();
if ( is_array( $arg ) && 1 == count( $arg ) && isset( $arg[0] ) && is_object( $arg[0] ) ) { // array(&$this)
$args[] =& $arg[0];
} else {
$args[] = $arg;
}
for ( $a = 2, $num = func_num_args(); $a < $num; $a++ ) {
$args[] = func_get_arg( $a );
}
$wp_filter[ $tag ]->do_action( $args );
array_pop( $wp_current_filter );
}
/**
* Retrieve the number of times an action is fired.
*
* @since 2.1.0
*
* @global array $wp_actions Increments the amount of times action was triggered.
*
* @param string $tag The name of the action hook.
* @return int The number of times action hook $tag is fired.
*/
function did_action( $tag ) {
global $wp_actions;
if ( ! isset( $wp_actions[ $tag ] ) ) {
return 0;
}
return $wp_actions[ $tag ];
}
/**
* Execute functions hooked on a specific action hook, specifying arguments in an array.
*
* @since 2.1.0
*
* @see do_action() This function is identical, but the arguments passed to the
* functions hooked to $tag< are supplied using an array.
* @global array $wp_filter Stores all of the filters
* @global array $wp_actions Increments the amount of times action was triggered.
* @global array $wp_current_filter Stores the list of current filters with the current one last
*
* @param string $tag The name of the action to be executed.
* @param array $args The arguments supplied to the functions hooked to `$tag`.
*/
function do_action_ref_array( $tag, $args ) {
global $wp_filter, $wp_actions, $wp_current_filter;
if ( ! isset( $wp_actions[ $tag ] ) ) {
$wp_actions[ $tag ] = 1;
} else {
++$wp_actions[ $tag ];
}
// Do 'all' actions first
if ( isset( $wp_filter['all'] ) ) {
$wp_current_filter[] = $tag;
$all_args = func_get_args();
_wp_call_all_hook( $all_args );
}
if ( ! isset( $wp_filter[ $tag ] ) ) {
if ( isset( $wp_filter['all'] ) ) {
array_pop( $wp_current_filter );
}
return;
}
if ( ! isset( $wp_filter['all'] ) ) {
$wp_current_filter[] = $tag;
}
$wp_filter[ $tag ]->do_action( $args );
array_pop( $wp_current_filter );
}
/**
* Check if any action has been registered for a hook.
*
* @since 2.5.0
*
* @see has_filter() has_action() is an alias of has_filter().
*
* @param string $tag The name of the action hook.
* @param callable|bool $function_to_check Optional. The callback to check for. Default false.
* @return bool|int If $function_to_check is omitted, returns boolean for whether the hook has
* anything registered. When checking a specific function, the priority of that
* hook is returned, or false if the function is not attached. When using the
* $function_to_check argument, this function may return a non-boolean value
* that evaluates to false (e.g.) 0, so use the === operator for testing the
* return value.
*/
function has_action( $tag, $function_to_check = false ) {
return has_filter( $tag, $function_to_check );
}
/**
* Removes a function from a specified action hook.
*
* This function removes a function attached to a specified action hook. This
* method can be used to remove default functions attached to a specific filter
* hook and possibly replace them with a substitute.
*
* @since 1.2.0
*
* @param string $tag The action hook to which the function to be removed is hooked.
* @param callable $function_to_remove The name of the function which should be removed.
* @param int $priority Optional. The priority of the function. Default 10.
* @return bool Whether the function is removed.
*/
function remove_action( $tag, $function_to_remove, $priority = 10 ) {
return remove_filter( $tag, $function_to_remove, $priority );
}
/**
* Remove all of the hooks from an action.
*
* @since 2.7.0
*
* @param string $tag The action to remove hooks from.
* @param int|bool $priority The priority number to remove them from. Default false.
* @return true True when finished.
*/
function remove_all_actions( $tag, $priority = false ) {
return remove_all_filters( $tag, $priority );
}
/**
* Fires functions attached to a deprecated filter hook.
*
* When a filter hook is deprecated, the apply_filters() call is replaced with
* apply_filters_deprecated(), which triggers a deprecation notice and then fires
* the original filter hook.
*
* Note: the value and extra arguments passed to the original apply_filters() call
* must be passed here to `$args` as an array. For example:
*
* // Old filter.
* return apply_filters( 'wpdocs_filter', $value, $extra_arg );
*
* // Deprecated.
* return apply_filters_deprecated( 'wpdocs_filter', array( $value, $extra_arg ), '4.9', 'wpdocs_new_filter' );
*
* @since 4.6.0
*
* @see _deprecated_hook()
*
* @param string $tag The name of the filter hook.
* @param array $args Array of additional function arguments to be passed to apply_filters().
* @param string $version The version of WordPress that deprecated the hook.
* @param string $replacement Optional. The hook that should have been used. Default false.
* @param string $message Optional. A message regarding the change. Default null.
*/
function apply_filters_deprecated( $tag, $args, $version, $replacement = false, $message = null ) {
if ( ! has_filter( $tag ) ) {
return $args[0];
}
_deprecated_hook( $tag, $version, $replacement, $message );
return apply_filters_ref_array( $tag, $args );
}
/**
* Fires functions attached to a deprecated action hook.
*
* When an action hook is deprecated, the do_action() call is replaced with
* do_action_deprecated(), which triggers a deprecation notice and then fires
* the original hook.
*
* @since 4.6.0
*
* @see _deprecated_hook()
*
* @param string $tag The name of the action hook.
* @param array $args Array of additional function arguments to be passed to do_action().
* @param string $version The version of WordPress that deprecated the hook.
* @param string $replacement Optional. The hook that should have been used.
* @param string $message Optional. A message regarding the change.
*/
function do_action_deprecated( $tag, $args, $version, $replacement = false, $message = null ) {
if ( ! has_action( $tag ) ) {
return;
}
_deprecated_hook( $tag, $version, $replacement, $message );
do_action_ref_array( $tag, $args );
}
//
// Functions for handling plugins.
//
/**
* Gets the basename of a plugin.
*
* This method extracts the name of a plugin from its filename.
*
* @since 1.5.0
*
* @global array $wp_plugin_paths
*
* @param string $file The filename of plugin.
* @return string The name of a plugin.
*/
function plugin_basename( $file ) {
global $wp_plugin_paths;
// $wp_plugin_paths contains normalized paths.
$file = wp_normalize_path( $file );
arsort( $wp_plugin_paths );
foreach ( $wp_plugin_paths as $dir => $realdir ) {
if ( strpos( $file, $realdir ) === 0 ) {
$file = $dir . substr( $file, strlen( $realdir ) );
}
}
$plugin_dir = wp_normalize_path( WP_PLUGIN_DIR );
$mu_plugin_dir = wp_normalize_path( WPMU_PLUGIN_DIR );
$file = preg_replace( '#^' . preg_quote( $plugin_dir, '#' ) . '/|^' . preg_quote( $mu_plugin_dir, '#' ) . '/#', '', $file ); // get relative path from plugins dir
$file = trim( $file, '/' );
return $file;
}
/**
* Register a plugin's real path.
*
* This is used in plugin_basename() to resolve symlinked paths.
*
* @since 3.9.0
*
* @see wp_normalize_path()
*
* @global array $wp_plugin_paths
*
* @staticvar string $wp_plugin_path
* @staticvar string $wpmu_plugin_path
*
* @param string $file Known path to the file.
* @return bool Whether the path was able to be registered.
*/
function wp_register_plugin_realpath( $file ) {
global $wp_plugin_paths;
// Normalize, but store as static to avoid recalculation of a constant value
static $wp_plugin_path = null, $wpmu_plugin_path = null;
if ( ! isset( $wp_plugin_path ) ) {
$wp_plugin_path = wp_normalize_path( WP_PLUGIN_DIR );
$wpmu_plugin_path = wp_normalize_path( WPMU_PLUGIN_DIR );
}
$plugin_path = wp_normalize_path( dirname( $file ) );
$plugin_realpath = wp_normalize_path( dirname( realpath( $file ) ) );
if ( $plugin_path === $wp_plugin_path || $plugin_path === $wpmu_plugin_path ) {
return false;
}
if ( $plugin_path !== $plugin_realpath ) {
$wp_plugin_paths[ $plugin_path ] = $plugin_realpath;
}
return true;
}
/**
* Get the filesystem directory path (with trailing slash) for the plugin __FILE__ passed in.
*
* @since 2.8.0
*
* @param string $file The filename of the plugin (__FILE__).
* @return string the filesystem path of the directory that contains the plugin.
*/
function plugin_dir_path( $file ) {
return trailingslashit( dirname( $file ) );
}
/**
* Get the URL directory path (with trailing slash) for the plugin __FILE__ passed in.
*
* @since 2.8.0
*
* @param string $file The filename of the plugin (__FILE__).
* @return string the URL path of the directory that contains the plugin.
*/
function plugin_dir_url( $file ) {
return trailingslashit( plugins_url( '', $file ) );
}
/**
* Set the activation hook for a plugin.
*
* When a plugin is activated, the action 'activate_PLUGINNAME' hook is
* called. In the name of this hook, PLUGINNAME is replaced with the name
* of the plugin, including the optional subdirectory. For example, when the
* plugin is located in wp-content/plugins/sampleplugin/sample.php, then
* the name of this hook will become 'activate_sampleplugin/sample.php'.
*
* When the plugin consists of only one file and is (as by default) located at
* wp-content/plugins/sample.php the name of this hook will be
* 'activate_sample.php'.
*
* @since 2.0.0
*
* @param string $file The filename of the plugin including the path.
* @param callable $function The function hooked to the 'activate_PLUGIN' action.
*/
function register_activation_hook( $file, $function ) {
$file = plugin_basename( $file );
add_action( 'activate_' . $file, $function );
}
/**
* Set the deactivation hook for a plugin.
*
* When a plugin is deactivated, the action 'deactivate_PLUGINNAME' hook is
* called. In the name of this hook, PLUGINNAME is replaced with the name
* of the plugin, including the optional subdirectory. For example, when the
* plugin is located in wp-content/plugins/sampleplugin/sample.php, then
* the name of this hook will become 'deactivate_sampleplugin/sample.php'.
*
* When the plugin consists of only one file and is (as by default) located at
* wp-content/plugins/sample.php the name of this hook will be
* 'deactivate_sample.php'.
*
* @since 2.0.0
*
* @param string $file The filename of the plugin including the path.
* @param callable $function The function hooked to the 'deactivate_PLUGIN' action.
*/
function register_deactivation_hook( $file, $function ) {
$file = plugin_basename( $file );
add_action( 'deactivate_' . $file, $function );
}
/**
* Set the uninstallation hook for a plugin.
*
* Registers the uninstall hook that will be called when the user clicks on the
* uninstall link that calls for the plugin to uninstall itself. The link won't
* be active unless the plugin hooks into the action.
*
* The plugin should not run arbitrary code outside of functions, when
* registering the uninstall hook. In order to run using the hook, the plugin
* will have to be included, which means that any code laying outside of a
* function will be run during the uninstallation process. The plugin should not
* hinder the uninstallation process.
*
* If the plugin can not be written without running code within the plugin, then
* the plugin should create a file named 'uninstall.php' in the base plugin
* folder. This file will be called, if it exists, during the uninstallation process
* bypassing the uninstall hook. The plugin, when using the 'uninstall.php'
* should always check for the 'WP_UNINSTALL_PLUGIN' constant, before
* executing.
*
* @since 2.7.0
*
* @param string $file Plugin file.
* @param callable $callback The callback to run when the hook is called. Must be
* a static method or function.
*/
function register_uninstall_hook( $file, $callback ) {
if ( is_array( $callback ) && is_object( $callback[0] ) ) {
_doing_it_wrong( __FUNCTION__, __( 'Only a static class method or function can be used in an uninstall hook.' ), '3.1.0' );
return;
}
/*
* The option should not be autoloaded, because it is not needed in most
* cases. Emphasis should be put on using the 'uninstall.php' way of
* uninstalling the plugin.
*/
$uninstallable_plugins = (array) get_option( 'uninstall_plugins' );
$uninstallable_plugins[ plugin_basename( $file ) ] = $callback;
update_option( 'uninstall_plugins', $uninstallable_plugins );
}
/**
* Call the 'all' hook, which will process the functions hooked into it.
*
* The 'all' hook passes all of the arguments or parameters that were used for
* the hook, which this function was called for.
*
* This function is used internally for apply_filters(), do_action(), and
* do_action_ref_array() and is not meant to be used from outside those
* functions. This function does not check for the existence of the all hook, so
* it will fail unless the all hook exists prior to this function call.
*
* @since 2.5.0
* @access private
*
* @global array $wp_filter Stores all of the filters
*
* @param array $args The collected parameters from the hook that was called.
*/
function _wp_call_all_hook( $args ) {
global $wp_filter;
$wp_filter['all']->do_all_hook( $args );
}
/**
* Build Unique ID for storage and retrieval.
*
* The old way to serialize the callback caused issues and this function is the
* solution. It works by checking for objects and creating a new property in
* the class to keep track of the object and new objects of the same class that
* need to be added.
*
* It also allows for the removal of actions and filters for objects after they
* change class properties. It is possible to include the property $wp_filter_id
* in your class and set it to "null" or a number to bypass the workaround.
* However this will prevent you from adding new classes and any new classes
* will overwrite the previous hook by the same class.
*
* Functions and static method callbacks are just returned as strings and
* shouldn't have any speed penalty.
*
* @link https://core.trac.wordpress.org/ticket/3875
*
* @since 2.2.3
* @access private
*
* @global array $wp_filter Storage for all of the filters and actions.
* @staticvar int $filter_id_count
*
* @param string $tag Used in counting how many hooks were applied
* @param callable $function Used for creating unique id
* @param int|bool $priority Used in counting how many hooks were applied. If === false
* and $function is an object reference, we return the unique
* id only if it already has one, false otherwise.
* @return string|false Unique ID for usage as array key or false if $priority === false
* and $function is an object reference, and it does not already have
* a unique id.
*/
function _wp_filter_build_unique_id( $tag, $function, $priority ) {
global $wp_filter;
static $filter_id_count = 0;
if ( is_string( $function ) ) {
return $function;
}
if ( is_object( $function ) ) {
// Closures are currently implemented as objects
$function = array( $function, '' );
} else {
$function = (array) $function;
}
if ( is_object( $function[0] ) ) {
// Object Class Calling
if ( function_exists( 'spl_object_hash' ) ) {
return spl_object_hash( $function[0] ) . $function[1];
} else {
$obj_idx = get_class( $function[0] ) . $function[1];
if ( ! isset( $function[0]->wp_filter_id ) ) {
if ( false === $priority ) {
return false;
}
$obj_idx .= isset( $wp_filter[ $tag ][ $priority ] ) ? count( (array) $wp_filter[ $tag ][ $priority ] ) : $filter_id_count;
$function[0]->wp_filter_id = $filter_id_count;
++$filter_id_count;
} else {
$obj_idx .= $function[0]->wp_filter_id;
}
return $obj_idx;
}
} elseif ( is_string( $function[0] ) ) {
// Static Calling
return $function[0] . '::' . $function[1];
}
}