WP Merge to rev 5499, this is a big one! Test it before you put it live!

Test only, not for production use yet


git-svn-id: http://svn.automattic.com/wordpress-mu/trunk@972 7be80a69-a1ef-0310-a953-fb0f7c49ff36

1 files changed, 158 insertions, 22 deletions

diff --git a/wp-includes/plugin.php b/wp-includes/plugin.php
index 61580e7..b8bf524 100644
--- a/wp-includes/plugin.php
+++ b/wp-includes/plugin.php
@@ -1,25 +1,53 @@
 <?php
 
-//
-// Filter functions, the core of the WP plugin architecture.
-//
-
+/**
+ * Hooks a function to a specific filter action.
+ * 
+ * Filters are the hooks that WordPress launches to modify text of various types
+ * before adding it to the database or sending it to the browser screen. Plugins 
+ * can specify that one or more of its PHP functions is executed to 
+ * modify specific types of text at these times, using the Filter API.
+ * See the [Plugin API] for a list of filter hooks. 
+ *
+ * @param string $tag The name of the filter to hook the <tt>$function_to_add</tt> to.
+ * @param callback $function_to_add The name of the function to be called 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 $accepted_args optional. The number of arguments the function accept (default 1). In WordPress 1.5.1+, hooked functions can take extra arguments that are set when the matching do_action() or apply_filters() call is run.
+ * @return boolean true if the <tt>$function_to_add</tt> is added succesfully to filter <tt>$tag</tt>. How many arguments your function takes. In WordPress 1.5.1+, hooked functions can take extra arguments that are set when the matching <tt>do_action()</tt> or <tt>apply_filters()</tt> call is run. For example, the action <tt>comment_id_not_found</tt> will pass any functions that hook onto it the ID of the requested comment.
+ */
 function add_filter($tag, $function_to_add, $priority = 10, $accepted_args = 1) {
-	global $wp_filter;
+	global $wp_filter, $merged_filters;
 
 	// So the format is wp_filter['tag']['array of priorities']['array of functions serialized']['array of ['array (functions, accepted_args)]']
 	$wp_filter[$tag][$priority][serialize($function_to_add)] = array('function' => $function_to_add, 'accepted_args' => $accepted_args);
+	unset( $merged_filters[ $tag ] );
 	return true;
 }
 
+/**
+ * Call the functions added to a filter hook.
+ * 
+ * The callback functions attached to filter hook <tt>$tag</tt> are invoked by
+ * calling this function. This function can be used to create a new filter hook
+ * by simply calling this function with the name of the new hook specified using
+ * the <tt>$tag</a> parameter.
+ * @uses merge_filters Merges the filter hooks using this function.
+ * @param string $tag The name of the filter hook.
+ * @param string $string The text on which the filters hooked to <tt>$tag</tt> are applied on.
+ * @param mixed $var,... Additional variables passed to the functions hooked to <tt>$tag</tt>.
+ * @return string The text in <tt>$string</tt> after all hooked functions are applied to it.
+ */
 function apply_filters($tag, $string) {
-	global $wp_filter;
+	global $wp_filter, $merged_filters;
 
-	merge_filters($tag);
+	if ( !isset( $merged_filters[ $tag ] ) )
+		merge_filters($tag);
 
 	if ( !isset($wp_filter[$tag]) )
 		return $string;
 
+	reset( $wp_filter[ $tag ] );
+
 	$args = func_get_args();
 
 	do{
@@ -34,37 +62,87 @@ function apply_filters($tag, $string) {
 	return $string;
 }
 
+/**
+ * Merge the filter functions of a specific filter hook with generic filter functions.
+ * 
+ * It is possible to defined generic filter functions using the filter hook 
+ * <em>all</e>. These functions are called for every filter tag. This function 
+ * merges the functions attached to the <em>all</em> hook with the functions
+ * of a specific hoook defined by <tt>$tag</tt>.
+ * @param string $tag The filter hook of which the functions should be merged.
+ */
 function merge_filters($tag) {
-	global $wp_filter;
+	global $wp_filter, $merged_filters;
 
-	if ( isset($wp_filter['all']) )
+	if ( isset($wp_filter['all']) && is_array($wp_filter['all']) )
 		$wp_filter[$tag] = array_merge($wp_filter['all'], (array) $wp_filter[$tag]);
 
 	if ( isset($wp_filter[$tag]) ){
 		reset($wp_filter[$tag]);
 		uksort($wp_filter[$tag], "strnatcasecmp");
 	}
+	$merged_filters[ $tag ] = true;
 }
 
+/**
+ * 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.
+ * @param string $tag The filter hook to which the function to be removed is hooked.
+ * @param callback $function_to_remove The name of the function which should be removed.
+ * @param int $priority optional. The priority of the function (default: 10).
+ * @param int $accepted_args optional. The number of arguments the function accpets (default: 1).
+ * @return boolean Whether the function is removed.
+ */
 function remove_filter($tag, $function_to_remove, $priority = 10, $accepted_args = 1) {
-	global $wp_filter;
+	$function_to_remove = serialize($function_to_remove);
 
-	unset($GLOBALS['wp_filter'][$tag][$priority][serialize($function_to_remove)]);
+	$r = isset($GLOBALS['wp_filter'][$tag][$priority][$function_to_remove]);
 
-	return true;
-}
+	unset($GLOBALS['wp_filter'][$tag][$priority][$function_to_remove]);
+	unset($GLOBALS['merged_filters'][$tag]);
 
-//
-// Action functions
-//
+	return $r;
+}
 
+/**
+ * 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.
+ * 
+ * @param string $tag The name of the action to which the <tt>$function_to-add</tt> is hooked.
+ * @param callback $function_to_add The name of the function you wish to be called. Note: any of the syntaxes explained in the PHP documentation for the 'callback' type (http://us2.php.net/manual/en/language.pseudo-types.php#language.types.callback) are valid.
+ * @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 $accepted_args optional. The number of arguments the function accept (default 1). In WordPress 1.5.1+, hooked functions can take extra arguments that are set when the matching do_action() or apply_filters() call is run. 
+ * @return boolean Always true.
+ */
 function add_action($tag, $function_to_add, $priority = 10, $accepted_args = 1) {
 	add_filter($tag, $function_to_add, $priority, $accepted_args);
 }
 
+/**
+ * Execute functions hooked on a specific action hook.
+ * 
+ * This function invokes all functions attached to action hook <tt>$tag</tt>.
+ * It is possible to create new action hooks by simply calling this function,
+ * specifying the name of the new hook using the <tt>$tag</tt> parameter.
+ * @uses merge_filters
+ * @param string $tag The name of the action to be executed.
+ * @param mixed $arg,... Optional additional arguments which are passed on to the functions hooked to the action. 
+ */
 function do_action($tag, $arg = '') {
 	global $wp_filter, $wp_actions;
 
+	if ( is_array($wp_actions) )
+		$wp_actions[] = $tag;
+	else
+		$wp_actions = array($tag);
+
 	$args = array();
 	if ( is_array($arg) && 1 == count($arg) && is_object($arg[0]) ) // array(&$this)
 		$args[] =& $arg[0];
@@ -85,19 +163,30 @@ function do_action($tag, $arg = '') {
 
 	} while ( next($wp_filter[$tag]) );
 
-	if ( is_array($wp_actions) )
-		$wp_actions[] = $tag;
-	else
-		$wp_actions = array($tag);
 }
 
-// Returns the number of times an action has been done
+/**
+ * Return the number times an action is fired.
+ * @param string $tag The name of the action hook.
+ * @return int The number of times action hook <tt>$tag</tt> is fired
+ */
 function did_action($tag) {
 	global $wp_actions;
 
+	if ( empty($wp_actions) )
+		return 0;
+
 	return count(array_keys($wp_actions, $tag));
 }
 
+/**
+ * Execute functions hooked on a specific action hook, specifying arguments in a array.
+ * 
+ * This function is identical to {@link do_action}, but the argumetns passe to 
+ * the functions hooked to <tt>$tag</tt> are supplied using an array.
+ * @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>
+ */
 function do_action_ref_array($tag, $args) {
 	global $wp_filter, $wp_actions;
 
@@ -120,25 +209,72 @@ function do_action_ref_array($tag, $args) {
 
 }
 
+/**
+ * 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.
+ * @param string $tag The action hook to which the function to be removed is hooked.
+ * @param callback $function_to_remove The name of the function which should be removed.
+ * @param int $priority optional The priority of the function (default: 10).
+ * @param int $accepted_args optional. The number of arguments the function accpets (default: 1).
+ * @return boolean Whether the function is removed.
+ */
 function remove_action($tag, $function_to_remove, $priority = 10, $accepted_args = 1) {
-	remove_filter($tag, $function_to_remove, $priority, $accepted_args);
+	return remove_filter($tag, $function_to_remove, $priority, $accepted_args);
 }
 
 //
 // Functions for handling plugins.
 //
 
+/**
+ * Gets the basename of a plugin.
+ * 
+ * This method extract the name of a plugin from its filename.
+ * @param string $file The filename of plugin.
+ * @return string The name of a plugin.
+ */
 function plugin_basename($file) {
 	$file = preg_replace('|\\\\+|', '\\\\', $file);
 	$file = preg_replace('/^.*wp-content[\\\\\/]plugins[\\\\\/]/', '', $file);
 	return $file;
 }
 
+/**
+ * Hook a function on a plugin activation action hook.
+ * 
+ * When a plugin is activated, the action 'activate_PLUGINNAME' hook is
+ * activated. 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 <tt>wp-content/plugin/sampleplugin/sample.php</tt>, 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 
+ * <tt>wp-content/plugin/sample.php</tt> the name of this hook will be 
+ * 'activate_sample.php'.
+ * @param string $file The filename of the plugin including the path.
+ * @param string $function the function hooked to the 'activate_PLUGIN' action.
+ */
 function register_activation_hook($file, $function) {
 	$file = plugin_basename($file);
 	add_action('activate_' . $file, $function);
 }
 
+/**
+ * Hook a function on a plugin deactivation action hook.
+ * 
+ * When a plugin is deactivated, the action 'deactivate_PLUGINNAME' hook is
+ * deactivated. 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 <tt>wp-content/plugin/sampleplugin/sample.php</tt>, 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 
+ * <tt>wp-content/plugin/sample.php</tt> the name of this hook will be 
+ * 'activate_sample.php'.
+ * @param string $file The filename of the plugin including the path.
+ * @param string $function the function hooked to the 'activate_PLUGIN' action.
+ */
 function register_deactivation_hook($file, $function) {
 	$file = plugin_basename($file);
 	add_action('deactivate_' . $file, $function);