/**
* 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 $tag parameter.
*
* The function allows for additional arguments to be added and passed to hooks.
* <code>
* function example_hook($string, $arg1, $arg2)
* {
* //Do stuff
* return $string;
* }
* $value = apply_filters('example_filter', 'filter me', 'arg1', 'arg2');
* </code>
*
* @package WordPress
* @global array $filters Stores all of the filters
*
* @param string $filter_name The name of the filter hook.
* @param mixed $value The value on which the filters hooked to <tt>$filter_name</tt> are applied on.
* @param mixed $var,... Additional variables passed to the functions hooked to <tt>$filter_name</tt>.
* @return mixed The filtered value after all hooked functions are applied to it.
*/
function apply_filters($filter_name, $string = '')
{
global $filters;
$args = func_get_args();
// Do 'all' actions first
if (isset($filters['all'])) {
_call_all_hook($args);
}
if (!isset($filters[$filter_name])) {
return $string;
}
ksort($filters[$filter_name]);
reset($filters[$filter_name]);
global $current_filter;
$current_filter = $filter_name;
do {
foreach ((array) current($filters[$filter_name]) as $filter) {
$filter_function = $filter['function'];
$string = call_user_func_array($filter['function'], array_slice($args, 1, (int) $filter['num_args']));
}
} while (next($filters[$filter_name]) !== false);
$current_filter = '';
return $string;
}
/**
* Execute functions hooked on a specific action hook, specifying arguments in an array.
*
* @see do_action() This function is identical, but the arguments passed to the
* functions hooked to <tt>$tag</tt> are supplied using an array.
*
* @package WordPress
* @subpackage Plugin
* @since 2.1
* @global array $wp_filter Stores all of the filters
* @global array $wp_actions Increments the amount of times action was triggered.
*
* @param string $tag The name of the action to be executed.
* @param array $args The arguments supplied to the functions hooked to <tt>$tag</tt>
* @return null Will return null if $tag does not exist in $wp_filter array
*/
function do_action_ref_array($tag, $args)
{
global $filters;
global $current_filter;
$current_filter = $tag;
// Do 'all' actions first
if (isset($filters['all'])) {
$all_args = func_get_args();
_call_all_hook($all_args);
}
if (!isset($filters[$tag])) {
return;
}
ksort($filters[$tag]);
reset($filters[$tag]);
do {
foreach ((array) current($filters[$tag]) as $action) {
call_user_func_array($action['function'], array_slice($args, 0, (int) $action['num_args']));
}
} while (next($filters[$tag]) !== false);
$current_filter = '';
}
/**
* Execute functions hooked on a specific filter hook, specifying arguments in an array.
*
* @see apply_filters() This function is identical, but the arguments passed to the
* functions hooked to `$tag` are supplied using an array.
*
* @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, $args)
{
// Do 'all' actions first
if (isset($this->filter['all'])) {
$this->current_filter[] = $tag;
$all_args = func_get_args();
_call_all_hook($all_args);
}
if (!isset($this->filter[$tag])) {
if (isset($this->filter['all'])) {
array_pop($this->current_filter);
}
return $args[0];
}
if (!isset($this->filter['all'])) {
$this->current_filter[] = $tag;
}
// Sort
if (!isset($this->merged_filters[$tag])) {
ksort($this->filter[$tag]);
$this->merged_filters[$tag] = true;
}
reset($this->filter[$tag]);
do {
foreach ((array) current($this->filter[$tag]) as $the_) {
if (!is_null($the_['function'])) {
$args[0] = call_user_func_array($the_['function'], array_slice($args, 0, (int) $the_['accepted_args']));
}
}
} while (next($this->filter[$tag]) !== false);
array_pop($this->current_filter);
return $args[0];
}