classes[$class]) || !include($CONFIG->classes[$class])) {
		return false;
	}
}
/**
 * Register all files found in $dir as classes
 * Need to be named MyClass.php
 *
 * @param string $dir The dir to look in
 *
 * @return void
 * @since 1.8.0
 */
function elgg_register_classes($dir) {
	$classes = elgg_get_file_list($dir, array(), array(), array('.php'));
	foreach ($classes as $class) {
		elgg_register_class(basename($class, '.php'), $class);
	}
}
/**
 * Register a classname to a file.
 *
 * @param string $class    The name of the class
 * @param string $location The location of the file
 *
 * @return true
 * @since 1.8.0
 */
function elgg_register_class($class, $location) {
	global $CONFIG;
	if (!isset($CONFIG->classes)) {
		$CONFIG->classes = array();
	}
	$CONFIG->classes[$class] = $location;
	return true;
}
/**
 * Register a php library.
 *
 * @param string $name     The name of the library
 * @param string $location The location of the file
 *
 * @return void
 * @since 1.8.0
 */
function elgg_register_library($name, $location) {
	global $CONFIG;
	if (!isset($CONFIG->libraries)) {
		$CONFIG->libraries = array();
	}
	$CONFIG->libraries[$name] = $location;
}
/**
 * Load a php library.
 *
 * @param string $name The name of the library
 *
 * @return void
 * @throws InvalidParameterException
 * @since 1.8.0
 */
function elgg_load_library($name) {
	global $CONFIG;
	if (!isset($CONFIG->libraries)) {
		$CONFIG->libraries = array();
	}
	if (!isset($CONFIG->libraries[$name])) {
		$error = elgg_echo('InvalidParameterException:LibraryNotRegistered', array($name));
		throw new InvalidParameterException($error);
	}
	if (!include_once($CONFIG->libraries[$name])) {
		$error = elgg_echo('InvalidParameterException:LibraryNotRegistered', array($name));
		throw new InvalidParameterException($error);
	}
}
/**
 * Forward to $location.
 *
 * Sends a 'Location: $location' header and exists.  If headers have
 * already been sent, returns FALSE.
 *
 * @param string $location URL to forward to browser to. Can be path relative to the network's URL.
 * @param string $reason   Short explanation for why we're forwarding
 *
 * @return False False if headers have been sent. Terminates execution if forwarding.
 */
function forward($location = "", $reason = 'system') {
	global $CONFIG;
	if (!headers_sent()) {
		if ($location === REFERER) {
			$location = $_SERVER['HTTP_REFERER'];
		}
		$location = elgg_normalize_url($location);
		// return new forward location or false to stop the forward or empty string to exit
		$current_page = current_page_url();
		$params = array('current_url' => $current_page, 'forward_url' => $location);
		$location = elgg_trigger_plugin_hook('forward', $reason, $params, $location);
		if ($location) {
			header("Location: {$location}");
			exit;
		} else if ($location === '') {
			exit;
		}
	} else {
		throw new SecurityException(elgg_echo('SecurityException:ForwardFailedToRedirect'));
	}
}
/**
 * Register a JavaScript file for inclusion
 *
 * This function handles adding JavaScript to a web page. If multiple
 * calls are made to register the same JavaScript file based on the $id
 * variable, only the last file is included. This allows a plugin to add
 * JavaScript from a view that may be called more than once. It also handles
 * more than one plugin adding the same JavaScript.
 *
 * jQuery plugins often have filenames such as jquery.rating.js. A best practice
 * is to base $name on the filename: "jquery.rating". It is recommended to not
 * use version numbers in the name.
 *
 * The JavaScript files can be local to the server or remote (such as
 * Google's CDN).
 *
 * @param string $name     An identifier for the JavaScript library
 * @param string $url      URL of the JavaScript file
 * @param string $location Page location: head or footer. (default: head)
 * @param int    $priority Priority of the JS file (lower numbers load earlier)
 *
 * @return bool
 * @since 1.8.0
 */
function elgg_register_js($name, $url, $location = 'head', $priority = null) {
	return elgg_register_external_file('js', $name, $url, $location, $priority);
}
/**
 * Unregister a JavaScript file
 *
 * @param string $name The identifier for the JavaScript library
 *
 * @return bool
 * @since 1.8.0
 */
function elgg_unregister_js($name) {
	return elgg_unregister_external_file('js', $name);
}
/**
 * Load a JavaScript resource on this page
 *
 * This must be called before elgg_view_page(). It can be called before the
 * script is registered. If you do not want a script loaded, unregister it.
 *
 * @param string $name Identifier of the JavaScript resource
 *
 * @return void
 * @since 1.8.0
 */
function elgg_load_js($name) {
	elgg_load_external_file('js', $name);
}
/**
 * Get the JavaScript URLs that are loaded
 *
 * @param string $location 'head' or 'footer'
 *
 * @return array
 * @since 1.8.0
 */
function elgg_get_loaded_js($location = 'head') {
	return elgg_get_loaded_external_files('js', $location);
}
/**
 * Register a CSS file for inclusion in the HTML head
 *
 * @param string $name     An identifier for the CSS file
 * @param string $url      URL of the CSS file
 * @param int    $priority Priority of the CSS file (lower numbers load earlier)
 *
 * @return bool
 * @since 1.8.0
 */
function elgg_register_css($name, $url, $priority = null) {
	return elgg_register_external_file('css', $name, $url, 'head', $priority);
}
/**
 * Unregister a CSS file
 *
 * @param string $name The identifier for the CSS file
 *
 * @return bool
 * @since 1.8.0
 */
function elgg_unregister_css($name) {
	return elgg_unregister_external_file('css', $name);
}
/**
 * Load a CSS file for this page
 *
 * This must be called before elgg_view_page(). It can be called before the
 * CSS file is registered. If you do not want a CSS file loaded, unregister it.
 *
 * @param string $name Identifier of the CSS file
 *
 * @return void
 * @since 1.8.0
 */
function elgg_load_css($name) {
	elgg_load_external_file('css', $name);
}
/**
 * Get the loaded CSS URLs
 *
 * @return array
 * @since 1.8.0
 */
function elgg_get_loaded_css() {
	return elgg_get_loaded_external_files('css', 'head');
}
/**
 * Core registration function for external files
 *
 * @param string $type     Type of external resource (js or css)
 * @param string $name     Identifier used as key
 * @param string $url      URL
 * @param string $location Location in the page to include the file
 * @param int    $priority Loading priority of the file
 *
 * @return bool
 * @since 1.8.0
 */
function elgg_register_external_file($type, $name, $url, $location, $priority = 500) {
	global $CONFIG;
	if (empty($name) || empty($url)) {
		return false;
	}
	$url = elgg_format_url($url);
	$url = elgg_normalize_url($url);
	
	elgg_bootstrap_externals_data_structure($type);
	$name = trim(strtolower($name));
	// normalize bogus priorities, but allow empty, null, and false to be defaults.
	if (!is_numeric($priority)) {
		$priority = 500;
	}
	// no negative priorities right now.
	$priority = max((int)$priority, 0);
	$item = elgg_extract($name, $CONFIG->externals_map[$type]);
	if ($item) {
		// updating a registered item
		// don't update loaded because it could already be set
		$item->url = $url;
		$item->location = $location;
		// if loaded before registered, that means it hasn't been added to the list yet
		if ($CONFIG->externals[$type]->contains($item)) {
			$priority = $CONFIG->externals[$type]->move($item, $priority);
		} else {
			$priority = $CONFIG->externals[$type]->add($item, $priority);
		}
	} else {
		$item = new stdClass();
		$item->loaded = false;
		$item->url = $url;
		$item->location = $location;
		$priority = $CONFIG->externals[$type]->add($item, $priority);
	}
	$CONFIG->externals_map[$type][$name] = $item;
	return $priority !== false;
}
/**
 * Unregister an external file
 *
 * @param string $type Type of file: js or css
 * @param string $name The identifier of the file
 *
 * @return bool
 * @since 1.8.0
 */
function elgg_unregister_external_file($type, $name) {
	global $CONFIG;
	elgg_bootstrap_externals_data_structure($type);
	$name = trim(strtolower($name));
	$item = elgg_extract($name, $CONFIG->externals_map[$type]);
	if ($item) {
		unset($CONFIG->externals_map[$type][$name]);
		return $CONFIG->externals[$type]->remove($item);
	}
	return false;
}
/**
 * Load an external resource for use on this page
 *
 * @param string $type Type of file: js or css
 * @param string $name The identifier for the file
 *
 * @return void
 * @since 1.8.0
 */
function elgg_load_external_file($type, $name) {
	global $CONFIG;
	elgg_bootstrap_externals_data_structure($type);
	$name = trim(strtolower($name));
	$item = elgg_extract($name, $CONFIG->externals_map[$type]);
	if ($item) {
		// update a registered item
		$item->loaded = true;
	} else {
		$item = new stdClass();
		$item->loaded = true;
		$item->url = '';
		$item->location = '';
		$priority = $CONFIG->externals[$type]->add($item);
		$CONFIG->externals_map[$type][$name] = $item;
	}
}
/**
 * Get external resource descriptors
 *
 * @param string $type     Type of file: js or css
 * @param string $location Page location
 *
 * @return array
 * @since 1.8.0
 */
function elgg_get_loaded_external_files($type, $location) {
	global $CONFIG;
	if (isset($CONFIG->externals) && $CONFIG->externals[$type] instanceof ElggPriorityList) {
		$items = $CONFIG->externals[$type]->getElements();
		$callback = "return \$v->loaded == true && \$v->location == '$location';";
		$items = array_filter($items, create_function('$v', $callback));
		if ($items) {
			array_walk($items, create_function('&$v,$k', '$v = $v->url;'));
		}
		return $items;
	}
	return array();
}
/**
 * Bootstraps the externals data structure in $CONFIG.
 *
 * @param string $type The type of external, js or css.
 * @access private
 */
function elgg_bootstrap_externals_data_structure($type) {
	global $CONFIG;
	if (!isset($CONFIG->externals)) {
		$CONFIG->externals = array();
	}
	if (!isset($CONFIG->externals[$type]) || !$CONFIG->externals[$type] instanceof ElggPriorityList) {
		$CONFIG->externals[$type] = new ElggPriorityList();
	}
	if (!isset($CONFIG->externals_map)) {
		$CONFIG->externals_map = array();
	}
	if (!isset($CONFIG->externals_map[$type])) {
		$CONFIG->externals_map[$type] = array();
	}
}
/**
 * Returns a list of files in $directory.
 *
 * Only returns files.  Does not recurse into subdirs.
 *
 * @param string $directory  Directory to look in
 * @param array  $exceptions Array of filenames to ignore
 * @param array  $list       Array of files to append to
 * @param mixed  $extensions Array of extensions to allow, NULL for all. Use a dot: array('.php').
 *
 * @return array Filenames in $directory, in the form $directory/filename.
 */
function elgg_get_file_list($directory, $exceptions = array(), $list = array(),
$extensions = NULL) {
	$directory = sanitise_filepath($directory);
	if ($handle = opendir($directory)) {
		while (($file = readdir($handle)) !== FALSE) {
			if (!is_file($directory . $file) || in_array($file, $exceptions)) {
				continue;
			}
			if (is_array($extensions)) {
				if (in_array(strrchr($file, '.'), $extensions)) {
					$list[] = $directory . $file;
				}
			} else {
				$list[] = $directory . $file;
			}
		}
		closedir($handle);
	}
	return $list;
}
/**
 * Sanitise file paths ensuring that they begin and end with slashes etc.
 *
 * @param string $path         The path
 * @param bool   $append_slash Add tailing slash
 *
 * @return string
 */
function sanitise_filepath($path, $append_slash = TRUE) {
	// Convert to correct UNIX paths
	$path = str_replace('\\', '/', $path);
	$path = str_replace('../', '/', $path);
	// replace // with / except when preceeded by :
	$path = preg_replace("/([^:])\/\//", "$1/", $path);
	// Sort trailing slash
	$path = trim($path);
	// rtrim defaults plus /
	$path = rtrim($path, " \n\t\0\x0B/");
	if ($append_slash) {
		$path = $path . '/';
	}
	return $path;
}
/**
 * Queues a message to be displayed.
 *
 * Messages will not be displayed immediately, but are stored in
 * for later display, usually upon next page load.
 *
 * The method of displaying these messages differs depending upon plugins and
 * viewtypes.  The core default viewtype retrieves messages in
 * {@link views/default/page/shells/default.php} and displays messages as
 * javascript popups.
 *
 * @internal Messages are stored as strings in the $_SESSION['msg'][$register] array.
 *
 * @warning This function is used to both add to and clear the message
 * stack.  If $messages is null, $register will be returned and cleared.
 * If $messages is null and $register is empty, all messages will be
 * returned and removed.
 *
 * @important This function handles the standard {@link system_message()} ($register =
 * 'messages') as well as {@link register_error()} messages ($register = 'errors').
 *
 * @param mixed  $message  Optionally, a single message or array of messages to add, (default: null)
 * @param string $register Types of message: "error", "success" (default: success)
 * @param bool   $count    Count the number of messages (default: false)
 *
 * @return true|false|array Either the array of messages, or a response regarding
 *                          whether the message addition was successful.
 * @todo Clean up. Separate registering messages and retrieving them.
 */
function system_messages($message = null, $register = "success", $count = false) {
	if (!isset($_SESSION['msg'])) {
		$_SESSION['msg'] = array();
	}
	if (!isset($_SESSION['msg'][$register]) && !empty($register)) {
		$_SESSION['msg'][$register] = array();
	}
	if (!$count) {
		if (!empty($message) && is_array($message)) {
			$_SESSION['msg'][$register] = array_merge($_SESSION['msg'][$register], $message);
			return true;
		} else if (!empty($message) && is_string($message)) {
			$_SESSION['msg'][$register][] = $message;
			return true;
		} else if (is_null($message)) {
			if ($register != "") {
				$returnarray = array();
				$returnarray[$register] = $_SESSION['msg'][$register];
				$_SESSION['msg'][$register] = array();
			} else {
				$returnarray = $_SESSION['msg'];
				$_SESSION['msg'] = array();
			}
			return $returnarray;
		}
	} else {
		if (!empty($register)) {
			return sizeof($_SESSION['msg'][$register]);
		} else {
			$count = 0;
			foreach ($_SESSION['msg'] as $register => $submessages) {
				$count += sizeof($submessages);
			}
			return $count;
		}
	}
	return false;
}
/**
 * Counts the number of messages, either globally or in a particular register
 *
 * @param string $register Optionally, the register
 *
 * @return integer The number of messages
 */
function count_messages($register = "") {
	return system_messages(null, $register, true);
}
/**
 * Display a system message on next page load.
 *
 * @see system_messages()
 *
 * @param string|array $message Message or messages to add
 *
 * @return bool
 */
function system_message($message) {
	return system_messages($message, "success");
}
/**
 * Display an error on next page load.
 *
 * @see system_messages()
 *
 * @param string|array $error Error or errors to add
 *
 * @return bool
 */
function register_error($error) {
	return system_messages($error, "error");
}
/**
 * Register a callback as an Elgg event handler.
 *
 * Events are emitted by Elgg when certain actions occur.  Plugins
 * can respond to these events or halt them completely by registering a handler
 * as a callback to an event.  Multiple handlers can be registered for
 * the same event and will be executed in order of $priority.  Any handler
 * returning false will halt the execution chain.
 *
 * This function is called with the event name, event type, and handler callback name.
 * Setting the optional $priority allows plugin authors to specify when the
 * callback should be run.  Priorities for plugins should be 1-1000.
 *
 * The callback is passed 3 arguments when called: $event, $type, and optional $params.
 *
 * $event is the name of event being emitted.
 * $type is the type of event or object concerned.
 * $params is an optional parameter passed that can include a related object.  See
 * specific event documentation for details on which events pass what parameteres.
 *
 * @tip If a priority isn't specified it is determined by the order the handler was
 * registered relative to the event and type.  For plugins, this generally means
 * the earlier the plugin is in the load order, the earlier the priorities are for
 * any event handlers.
 *
 * @tip $event and $object_type can use the special keyword 'all'.  Handler callbacks registered
 * with $event = all will be called for all events of type $object_type.  Similarly,
 * callbacks registered with $object_type = all will be called for all events of type
 * $event, regardless of $object_type.  If $event and $object_type both are 'all', the
 * handler callback will be called for all events.
 *
 * @tip Event handler callbacks are considered in the follow order:
 *  - Specific registration where 'all' isn't used.
 *  - Registration where 'all' is used for $event only.
 *  - Registration where 'all' is used for $type only.
 *  - Registration where 'all' is used for both.
 *
 * @warning If you use the 'all' keyword, you must have logic in the handler callback to
 * test the passed parameters before taking an action.
 *
 * @tip When referring to events, the preferred syntax is "event, type".
 *
 * @internal Events are stored in $CONFIG->events as:
 * 
 * $CONFIG->events[$event][$type][$priority] = $callback;
 * 
 *
 * @param string $event       The event type
 * @param string $object_type The object type
 * @param string $callback    The handler callback
 * @param int    $priority    The priority - 0 is default, negative before, positive after
 *
 * @return bool
 * @link http://docs.elgg.org/Tutorials/Plugins/Events
 * @example events/basic.php    Basic example of registering an event handler callback.
 * @example events/advanced.php Advanced example of registering an event handler
 *                              callback and halting execution.
 * @example events/all.php      Example of how to use the 'all' keyword.
 */
function elgg_register_event_handler($event, $object_type, $callback, $priority = 500) {
	global $CONFIG;
	if (empty($event) || empty($object_type)) {
		return FALSE;
	}
	if (!isset($CONFIG->events)) {
		$CONFIG->events = array();
	}
	if (!isset($CONFIG->events[$event])) {
		$CONFIG->events[$event] = array();
	}
	if (!isset($CONFIG->events[$event][$object_type])) {
		$CONFIG->events[$event][$object_type] = array();
	}
	if (!is_callable($callback)) {
		return FALSE;
	}
	$priority = max((int) $priority, 0);
	while (isset($CONFIG->events[$event][$object_type][$priority])) {
		$priority++;
	}
	$CONFIG->events[$event][$object_type][$priority] = $callback;
	ksort($CONFIG->events[$event][$object_type]);
	return TRUE;
}
/**
 * Unregisters a callback for an event.
 *
 * @param string $event       The event type
 * @param string $object_type The object type
 * @param string $callback    The callback
 *
 * @return void
 * @since 1.7
 */
function elgg_unregister_event_handler($event, $object_type, $callback) {
	global $CONFIG;
	foreach ($CONFIG->events[$event][$object_type] as $key => $event_callback) {
		if ($event_callback == $callback) {
			unset($CONFIG->events[$event][$object_type][$key]);
		}
	}
}
/**
 * Trigger an Elgg Event and run all handler callbacks registered to that event, type.
 *
 * This function runs all handlers registered to $event, $object_type or
 * the special keyword 'all' for either or both.
 *
 * $event is usually a verb: create, update, delete, annotation.
 *
 * $object_type is usually a noun: object, group, user, annotation, relationship, metadata.
 *
 * $object is usually an Elgg* object assciated with the event.
 *
 * @warning Elgg events should only be triggered by core.  Plugin authors should use
 * {@link trigger_elgg_plugin_hook()} instead.
 *
 * @tip When referring to events, the preferred syntax is "event, type".
 *
 * @internal Only rarely should events be changed, added, or removed in core.
 * When making changes to events, be sure to first create a ticket in trac.
 *
 * @internal @tip Think of $object_type as the primary namespace element, and
 * $event as the secondary namespace.
 *
 * @param string $event       The event type
 * @param string $object_type The object type
 * @param string $object      The object involved in the event
 *
 * @return bool The result of running all handler callbacks.
 * @link http://docs.elgg.org/Tutorials/Core/Events
 * @internal @example events/emit.php Basic emitting of an Elgg event.
 */
function elgg_trigger_event($event, $object_type, $object = null) {
	global $CONFIG;
	$events = array();
	if (isset($CONFIG->events[$event][$object_type])) {
		$events[] = $CONFIG->events[$event][$object_type];
	}
	if (isset($CONFIG->events['all'][$object_type])) {
		$events[] = $CONFIG->events['all'][$object_type];
	}
	if (isset($CONFIG->events[$event]['all'])) {
		$events[] = $CONFIG->events[$event]['all'];
	}
	if (isset($CONFIG->events['all']['all'])) {
		$events[] = $CONFIG->events['all']['all'];
	}
	$args = array($event, $object_type, $object);
	foreach ($events as $callback_list) {
		if (is_array($callback_list)) {
			foreach ($callback_list as $callback) {
				if (call_user_func_array($callback, $args) === FALSE) {
					return FALSE;
				}
			}
		}
	}
	return TRUE;
}
/**
 * Register a callback as a plugin hook handler.
 *
 * Plugin hooks allow developers to losely couple plugins and features by
 * repsonding to and emitting {@link elgg_trigger_plugin_hook()} customizable hooks.
 * Handler callbacks can respond to the hook, change the details of the hook, or
 * ignore it.
 *
 * Multiple handlers can be registered for a plugin hook, and each callback
 * is called in order of priority.  If the return value of a handler is not
 * null, that value is passed to the next callback in the call stack.  When all
 * callbacks have been run, the final value is passed back to the caller
 * via {@link elgg_trigger_plugin_hook()}.
 *
 * Similar to Elgg Events, plugin hook handler callbacks are registered by passing
 * a hook, a type, and a priority.
 *
 * The callback is passed 4 arguments when called: $hook, $type, $value, and $params.
 *
 *  - str $hook The name of the hook.
 *  - str $type The type of hook.
 *  - mixed $value The return value of the last handler or the default
 *  value if no other handlers have been called.
 *  - mixed $params An optional array of parameters.  Used to provide additional
 *  information to plugins.
 *
 * @internal Plugin hooks are stored in $CONFIG->hooks as:
 * 
 * $CONFIG->hooks[$hook][$type][$priority] = $callback;
 * 
 *
 * @tip Plugin hooks are similar to Elgg Events in that Elgg emits
 * a plugin hook when certain actions occur, but a plugin hook allows you to alter the
 * parameters, as well as halt execution.
 *
 * @tip If a priority isn't specified it is determined by the order the handler was
 * registered relative to the event and type.  For plugins, this generally means
 * the earlier the plugin is in the load order, the earlier the priorities are for
 * any event handlers.
 *
 * @tip Like Elgg Events, $hook and $type can use the special keyword 'all'.
 * Handler callbacks registered with $hook = all will be called for all hooks
 * of type $type.  Similarly, handlers registered with $type = all will be
 * called for all hooks of type $event, regardless of $object_type.  If $hook
 * and $type both are 'all', the handler will be called for all hooks.
 *
 * @tip Plugin hooks are sometimes used to gather lists from plugins.  This is
 * usually done by pushing elements into an array passed in $params.  Be sure
 * to append to and then return $value so you don't overwrite other plugin's
 * values.
 *
 * @warning Unlike Elgg Events, a handler that returns false will NOT halt the
 * execution chain.
 *
 * @param string   $hook     The name of the hook
 * @param string   $type     The type of the hook
 * @param callback $callback The name of a valid function or an array with object and method
 * @param int      $priority The priority - 500 is default, lower numbers called first
 *
 * @return bool
 *
 * @example hooks/register/basic.php Registering for a plugin hook and examining the variables.
 * @example hooks/register/advanced.php Registering for a plugin hook and changing the params.
 * @link http://docs.elgg.org/Tutorials/Plugins/Hooks
 * @since 1.8.0
 */
function elgg_register_plugin_hook_handler($hook, $type, $callback, $priority = 500) {
	global $CONFIG;
	if (empty($hook) || empty($type)) {
		return FALSE;
	}
	if (!isset($CONFIG->hooks)) {
		$CONFIG->hooks = array();
	}
	if (!isset($CONFIG->hooks[$hook])) {
		$CONFIG->hooks[$hook] = array();
	}
	if (!isset($CONFIG->hooks[$hook][$type])) {
		$CONFIG->hooks[$hook][$type] = array();
	}
	if (!is_callable($callback)) {
		return FALSE;
	}
	$priority = max((int) $priority, 0);
	while (isset($CONFIG->hooks[$hook][$type][$priority])) {
		$priority++;
	}
	$CONFIG->hooks[$hook][$type][$priority] = $callback;
	ksort($CONFIG->hooks[$hook][$type]);
	return TRUE;
}
/**
 * Unregister a callback as a plugin hook.
 *
 * @param string   $hook        The name of the hook
 * @param string   $entity_type The name of the type of entity (eg "user", "object" etc)
 * @param callback $callback    The PHP callback to be removed
 *
 * @return void
 * @since 1.8.0
 */
function elgg_unregister_plugin_hook_handler($hook, $entity_type, $callback) {
	global $CONFIG;
	foreach ($CONFIG->hooks[$hook][$entity_type] as $key => $hook_callback) {
		if ($hook_callback == $callback) {
			unset($CONFIG->hooks[$hook][$entity_type][$key]);
		}
	}
}
/**
 * Trigger a Plugin Hook and run all handler callbacks registered to that hook:type.
 *
 * This function runs all handlers regsitered to $hook, $type or
 * the special keyword 'all' for either or both.
 *
 * Use $params to send additional information to the handler callbacks.
 *
 * $returnvalue Is the initial value to pass to the handlers, which can
 * then change it.  It is useful to use $returnvalue to set defaults.
 * If no handlers are registered, $returnvalue is immediately returned.
 *
 * $hook is usually a verb: import, get_views, output.
 *
 * $type is usually a noun: user, ecml, page.
 *
 * @tip Like Elgg Events, $hook and $type can use the special keyword 'all'.
 * Handler callbacks registered with $hook = all will be called for all hooks
 * of type $type.  Similarly, handlers registered with $type = all will be
 * called for all hooks of type $event, regardless of $object_type.  If $hook
 * and $type both are 'all', the handler will be called for all hooks.
 *
 * @internal The checks for $hook and/or $type not being equal to 'all' is to
 * prevent a plugin hook being registered with an 'all' being called more than
 * once if the trigger occurs with an 'all'. An example in core of this is in
 * actions.php:
 * elgg_trigger_plugin_hook('action_gatekeeper:permissions:check', 'all', ...)
 *
 * @see elgg_register_plugin_hook_handler()
 *
 * @param string $hook        The name of the hook to trigger ("all" will
 *                            trigger for all $types regardless of $hook value)
 * @param string $type        The type of the hook to trigger ("all" will
 *                            trigger for all $hooks regardless of $type value)
 * @param mixed  $params      Additional parameters to pass to the handlers
 * @param mixed  $returnvalue An initial return value
 *
 * @return mixed|null The return value of the last handler callback called
 *
 * @example hooks/trigger/basic.php    Trigger a hook that determins if execution
 *                                     should continue.
 * @example hooks/trigger/advanced.php Trigger a hook with a default value and use
 *                                     the results to populate a menu.
 * @example hooks/basic.php            Trigger and respond to a basic plugin hook.
 * @link http://docs.elgg.org/Tutorials/Plugins/Hooks
 *
 * @since 1.8.0
 */
function elgg_trigger_plugin_hook($hook, $type, $params = null, $returnvalue = null) {
	global $CONFIG;
	$hooks = array();
	if (isset($CONFIG->hooks[$hook][$type])) {
		if ($hook != 'all' && $type != 'all') {
			$hooks[] = $CONFIG->hooks[$hook][$type];
		}
	}
	if (isset($CONFIG->hooks['all'][$type])) {
		if ($type != 'all') {
			$hooks[] = $CONFIG->hooks['all'][$type];
		}
	}
	if (isset($CONFIG->hooks[$hook]['all'])) {
		if ($hook != 'all') {
			$hooks[] = $CONFIG->hooks[$hook]['all'];
		}
	}
	if (isset($CONFIG->hooks['all']['all'])) {
		$hooks[] = $CONFIG->hooks['all']['all'];
	}
	foreach ($hooks as $callback_list) {
		if (is_array($callback_list)) {
			foreach ($callback_list as $hookcallback) {
				$args = array($hook, $type, $returnvalue, $params);
				$temp_return_value = call_user_func_array($hookcallback, $args);
				if (!is_null($temp_return_value)) {
					$returnvalue = $temp_return_value;
				}
			}
		}
	}
	return $returnvalue;
}
/**
 * Intercepts, logs, and displays uncaught exceptions.
 *
 * @warning This function should never be called directly.
 *
 * @see http://www.php.net/set-exception-handler
 *
 * @param Exception $exception The exception being handled
 *
 * @return void
 * @access private
 */
function _elgg_php_exception_handler($exception) {
	error_log("*** FATAL EXCEPTION *** : " . $exception);
	// Wipe any existing output buffer
	ob_end_clean();
	// make sure the error isn't cached
	header("Cache-Control: no-cache, must-revalidate", true);
	header('Expires: Fri, 05 Feb 1982 00:00:00 -0500', true);
	// @note Do not send a 500 header because it is not a server error
	try {
		// we don't want the 'pagesetup', 'system' event to fire
		global $CONFIG;
		$CONFIG->pagesetupdone = true;
		elgg_set_viewtype('failsafe');
		$body = elgg_view("messages/exceptions/exception", array('object' => $exception));
		echo elgg_view_page(elgg_echo('exception:title'), $body);
	} catch (Exception $e) {
		$timestamp = time();
		$message = $e->getMessage();
		echo "Fatal error in exception handler. Check log for Exception #$timestamp";
		error_log("Exception #$timestamp : fatal error in exception handler : $message");
	}
}
/**
 * Intercepts catchable PHP errors.
 *
 * @warning This function should never be called directly.
 *
 * @internal
 * For catchable fatal errors, throws an Exception with the error.
 *
 * For non-fatal errors, depending upon the debug settings, either
 * log the error or ignore it.
 *
 * @see http://www.php.net/set-error-handler
 *
 * @param int    $errno    The level of the error raised
 * @param string $errmsg   The error message
 * @param string $filename The filename the error was raised in
 * @param int    $linenum  The line number the error was raised at
 * @param array  $vars     An array that points to the active symbol table where error occurred
 *
 * @return true
 * @access private
 */
function _elgg_php_error_handler($errno, $errmsg, $filename, $linenum, $vars) {
	$error = date("Y-m-d H:i:s (T)") . ": \"$errmsg\" in file $filename (line $linenum)";
	switch ($errno) {
		case E_USER_ERROR:
			error_log("PHP ERROR: $error");
			register_error("ERROR: $error");
			// Since this is a fatal error, we want to stop any further execution but do so gracefully.
			throw new Exception($error);
			break;
		case E_WARNING :
		case E_USER_WARNING :
			error_log("PHP WARNING: $error");
			break;
		default:
			global $CONFIG;
			if (isset($CONFIG->debug) && $CONFIG->debug === 'NOTICE') {
				error_log("PHP NOTICE: $error");
			}
	}
	return true;
}
/**
 * Display or log a message.
 *
 * If $level is >= to the debug setting in {@link $CONFIG->debug}, the
 * message will be sent to {@link elgg_dump()}.  Messages with lower
 * priority than {@link $CONFIG->debug} are ignored.
 *
 * {@link elgg_dump()} outputs all levels but NOTICE to screen by default.
 *
 * @note No messages will be displayed unless debugging has been enabled.
 *
 * @param str $message User message
 * @param str $level   NOTICE | WARNING | ERROR | DEBUG
 *
 * @return bool
 * @since 1.7.0
 * @todo This is complicated and confusing.  Using int constants for debug levels will
 * make things easier.
 */
function elgg_log($message, $level = 'NOTICE') {
	global $CONFIG;
	// only log when debugging is enabled
	if (isset($CONFIG->debug)) {
		// debug to screen or log?
		$to_screen = !($CONFIG->debug == 'NOTICE');
		switch ($level) {
			case 'ERROR':
				// always report
				elgg_dump("$level: $message", $to_screen, $level);
				break;
			case 'WARNING':
			case 'DEBUG':
				// report except if user wants only errors
				if ($CONFIG->debug != 'ERROR') {
					elgg_dump("$level: $message", $to_screen, $level);
				}
				break;
			case 'NOTICE':
			default:
				// only report when lowest level is desired
				if ($CONFIG->debug == 'NOTICE') {
					elgg_dump("$level: $message", FALSE, $level);
				}
				break;
		}
		return TRUE;
	}
	return FALSE;
}
/**
 * Logs or displays $value.
 *
 * If $to_screen is true, $value is displayed to screen.  Else,
 * it is handled by PHP's {@link error_log()} function.
 *
 * A {@elgg_plugin_hook debug log} is called.  If a handler returns
 * false, it will stop the default logging method.
 *
 * @param mixed  $value     The value
 * @param bool   $to_screen Display to screen?
 * @param string $level     The debug level
 *
 * @return void
 * @since 1.7.0
 */
function elgg_dump($value, $to_screen = TRUE, $level = 'NOTICE') {
	global $CONFIG;
	// plugin can return false to stop the default logging method
	$params = array('level' => $level,
					'msg' => $value,
					'to_screen' => $to_screen);
	if (!elgg_trigger_plugin_hook('debug', 'log', $params, true)) {
		return;
	}
	// Do not want to write to screen before page creation has started.
	// This is not fool-proof but probably fixes 95% of the cases when logging
	// results in data sent to the browser before the page is begun.
	if (!isset($CONFIG->pagesetupdone)) {
		$to_screen = FALSE;
	}
	if ($to_screen == TRUE) {
		echo '
'; print_r($value); echo ''; } else { error_log(print_r($value, TRUE)); } } /** * Sends a notice about deprecated use of a function, view, etc. * * This function either displays or logs the deprecation message, * depending upon the deprecation policies in {@link CODING.txt}. * Logged messages are sent with the level of 'WARNING'. * * A user-visual message will be displayed if $dep_version is greater * than 1 minor releases lower than the current Elgg version, or at all * lower than the current Elgg major version. * * @note This will always at least log a warning. Don't use to pre-deprecate things. * This assumes we are releasing in order and deprecating according to policy. * * @see CODING.txt * * @param str $msg Message to log / display. * @param str $dep_version Human-readable *release* version: 1.7, 1.7.3 * @param int $backtrace_level How many levels back to display the backtrace. Useful if calling from * functions that are called from other places (like elgg_view()). Set * to -1 for a full backtrace. * * @return bool * @since 1.7.0 */ function elgg_deprecated_notice($msg, $dep_version, $backtrace_level = 1) { // if it's a major release behind, visual and logged // if it's a 1 minor release behind, visual and logged // if it's for current minor release, logged. // bugfixes don't matter because you're not deprecating between them, RIGHT? if (!$dep_version) { return FALSE; } $elgg_version = get_version(TRUE); $elgg_version_arr = explode('.', $elgg_version); $elgg_major_version = (int)$elgg_version_arr[0]; $elgg_minor_version = (int)$elgg_version_arr[1]; $dep_major_version = (int)$dep_version; $dep_minor_version = 10 * ($dep_version - $dep_major_version); $visual = FALSE; if (($dep_major_version < $elgg_major_version) || ($dep_minor_version < $elgg_minor_version)) { $visual = TRUE; } $msg = "Deprecated in $dep_major_version.$dep_minor_version: $msg"; if ($visual) { register_error($msg); } // Get a file and line number for the log. Never show this in the UI. // Skip over the function that sent this notice and see who called the deprecated // function itself. $msg .= " Called from "; $stack = array(); $backtrace = debug_backtrace(); // never show this call. array_shift($backtrace); $i = count($backtrace); foreach ($backtrace as $trace) { $stack[] = "[#$i] {$trace['file']}:{$trace['line']}"; $i--; if ($backtrace_level > 0) { if ($backtrace_level <= 1) { break; } $backtrace_level--; } } $msg .= implode("