<?php
/**
- * Hooks.php -- a tool for running hook functions
+ * A tool for running hook functions.
+ *
* Copyright 2004, 2005 Evan Prodromou <evan@wikitravel.org>.
*
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
*
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
*
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
*
* @author Evan Prodromou <evan@wikitravel.org>
- * @package MediaWiki
* @see hooks.txt
+ * @file
*/
+class MWHookException extends MWException {}
/**
- * Because programmers assign to $wgHooks, we need to be very
- * careful about its contents. So, there's a lot more error-checking
- * in here than would normally be necessary.
+ * Hooks class.
+ *
+ * Used to supersede $wgHooks, because globals are EVIL.
*/
-function wfRunHooks($event, $args = null) {
+class Hooks {
- global $wgHooks;
- $fname = 'wfRunHooks';
+ protected static $handlers = array();
- if (!is_array($wgHooks)) {
- throw new MWException("Global hooks array is not an array!\n");
- return false;
+ /**
+ * Attach an event handler to a given hook
+ *
+ * @param $name Mixed: name of hook
+ * @param $callback Mixed: callback function to attach
+ * @return void
+ */
+ public static function register( $name, $callback ) {
+ if( !isset( self::$handlers[$name] ) ) {
+ self::$handlers[$name] = array();
+ }
+
+ self::$handlers[$name][] = $callback;
}
- if (!array_key_exists($event, $wgHooks)) {
- return true;
+ /**
+ * Returns true if a hook has a function registered to it.
+ *
+ * @param $name Mixed: name of hook
+ * @return Boolean: true if a hook has a function registered to it
+ */
+ public static function isRegistered( $name ) {
+ if( !isset( self::$handlers[$name] ) ) {
+ self::$handlers[$name] = array();
+ }
+
+ return ( count( self::$handlers[$name] ) != 0 );
}
- if (!is_array($wgHooks[$event])) {
- throw new MWException("Hooks array for event '$event' is not an array!\n");
- return false;
+ /**
+ * Returns an array of all the event functions attached to a hook
+ *
+ * @param $name Mixed: name of the hook
+ * @return array
+ */
+ public static function getHandlers( $name ) {
+ if( !isset( self::$handlers[$name] ) ) {
+ return array();
+ }
+
+ return self::$handlers[$name];
}
- foreach ($wgHooks[$event] as $index => $hook) {
-
- $object = NULL;
- $method = NULL;
- $func = NULL;
- $data = NULL;
- $have_data = false;
-
- /* $hook can be: a function, an object, an array of $function and $data,
- * an array of just a function, an array of object and method, or an
- * array of object, method, and data.
- */
-
- if (is_array($hook)) {
- if (count($hook) < 1) {
- throw new MWException("Empty array in hooks for " . $event . "\n");
- } else if (is_object($hook[0])) {
- $object = $wgHooks[$event][$index][0];
- if (count($hook) < 2) {
- $method = "on" . $event;
- } else {
- $method = $hook[1];
- if (count($hook) > 2) {
- $data = $hook[2];
+ /**
+ * Call hook functions defined in Hooks::register
+ *
+ * Because programmers assign to $wgHooks, we need to be very
+ * careful about its contents. So, there's a lot more error-checking
+ * in here than would normally be necessary.
+ *
+ * @param $event String: event name
+ * @param $args Array: parameters passed to hook functions
+ * @return Boolean True if no handler aborted the hook
+ */
+ public static function run( $event, $args = array() ) {
+ global $wgHooks;
+
+ // Return quickly in the most common case
+ if ( !isset( self::$handlers[$event] ) && !isset( $wgHooks[$event] ) ) {
+ return true;
+ }
+
+ if ( !is_array( self::$handlers ) ) {
+ throw new MWException( "Local hooks array is not an array!\n" );
+ }
+
+ if ( !is_array( $wgHooks ) ) {
+ throw new MWException( "Global hooks array is not an array!\n" );
+ }
+
+ $new_handlers = (array) self::$handlers;
+ $old_handlers = (array) $wgHooks;
+
+ $hook_array = array_merge( $new_handlers, $old_handlers );
+
+ if ( !is_array( $hook_array[$event] ) ) {
+ throw new MWException( "Hooks array for event '$event' is not an array!\n" );
+ }
+
+ foreach ( $hook_array[$event] as $index => $hook ) {
+ $object = null;
+ $method = null;
+ $func = null;
+ $data = null;
+ $have_data = false;
+ $closure = false;
+ $badhookmsg = false;
+
+ /**
+ * $hook can be: a function, an object, an array of $function and
+ * $data, an array of just a function, an array of object and
+ * method, or an array of object, method, and data.
+ */
+ if ( is_array( $hook ) ) {
+ if ( count( $hook ) < 1 ) {
+ throw new MWException( 'Empty array in hooks for ' . $event . "\n" );
+ } elseif ( is_object( $hook[0] ) ) {
+ $object = $hook_array[$event][$index][0];
+ if ( $object instanceof Closure ) {
+ $closure = true;
+ if ( count( $hook ) > 1 ) {
+ $data = $hook[1];
+ $have_data = true;
+ }
+ } else {
+ if ( count( $hook ) < 2 ) {
+ $method = 'on' . $event;
+ } else {
+ $method = $hook[1];
+ if ( count( $hook ) > 2 ) {
+ $data = $hook[2];
+ $have_data = true;
+ }
+ }
+ }
+ } elseif ( is_string( $hook[0] ) ) {
+ $func = $hook[0];
+ if ( count( $hook ) > 1) {
+ $data = $hook[1];
$have_data = true;
}
+ } else {
+ throw new MWException( 'Unknown datatype in hooks for ' . $event . "\n" );
}
- } else if (is_string($hook[0])) {
- $func = $hook[0];
- if (count($hook) > 1) {
- $data = $hook[1];
- $have_data = true;
+ } elseif ( is_string( $hook ) ) { # functions look like strings, too
+ $func = $hook;
+ } elseif ( is_object( $hook ) ) {
+ $object = $hook_array[$event][$index];
+ if ( $object instanceof Closure ) {
+ $closure = true;
+ } else {
+ $method = "on" . $event;
}
} else {
- var_dump( $wgHooks );
- throw new MWException("Unknown datatype in hooks for " . $event . "\n");
+ throw new MWException( 'Unknown datatype in hooks for ' . $event . "\n" );
}
- } else if (is_string($hook)) { # functions look like strings, too
- $func = $hook;
- } else if (is_object($hook)) {
- $object = $wgHooks[$event][$index];
- $method = "on" . $event;
- } else {
- throw new MWException("Unknown datatype in hooks for " . $event . "\n");
- }
- /* We put the first data element on, if needed. */
+ /* We put the first data element on, if needed. */
+ if ( $have_data ) {
+ $hook_args = array_merge( array( $data ), $args );
+ } else {
+ $hook_args = $args;
+ }
- if ($have_data) {
- $hook_args = array_merge(array($data), $args);
- } else {
- $hook_args = $args;
- }
+ if ( $closure ) {
+ $callback = $object;
+ $func = "hook-$event-closure";
+ } elseif ( isset( $object ) ) {
+ $func = get_class( $object ) . '::' . $method;
+ $callback = array( $object, $method );
+ } else {
+ $callback = $func;
+ }
+ // Run autoloader (workaround for call_user_func_array bug)
+ is_callable( $callback );
- if ( isset( $object ) ) {
- $func = get_class( $object ) . '::' . $method;
- }
+ /**
+ * Call the hook. The documentation of call_user_func_array clearly
+ * states that FALSE is returned on failure. However this is not
+ * case always. In some version of PHP if the function signature
+ * does not match the call signature, PHP will issue an warning:
+ * Param y in x expected to be a reference, value given.
+ *
+ * In that case the call will also return null. The following code
+ * catches that warning and provides better error message. The
+ * function documentation also says that:
+ * In other words, it does not depend on the function signature
+ * whether the parameter is passed by a value or by a reference.
+ * There is also PHP bug http://bugs.php.net/bug.php?id=47554 which
+ * is unsurprisingly marked as bogus. In short handling of failures
+ * with call_user_func_array is a failure, the documentation for that
+ * function is wrong and misleading and PHP developers don't see any
+ * problem here.
+ */
+ $retval = null;
+ set_error_handler( 'Hooks::hookErrorHandler' );
+ wfProfileIn( $func );
+ try {
+ $retval = call_user_func_array( $callback, $hook_args );
+ } catch ( MWHookException $e ) {
+ $badhookmsg = $e->getMessage();
+ }
+ wfProfileOut( $func );
+ restore_error_handler();
- /* Call the hook. */
- wfProfileIn( $func );
- if( isset( $object ) ) {
- $retval = call_user_func_array(array($object, $method), $hook_args);
- } else {
- $retval = call_user_func_array($func, $hook_args);
+ /* String return is an error; false return means stop processing. */
+ if ( is_string( $retval ) ) {
+ throw new FatalError( $retval );
+ } elseif( $retval === null ) {
+ if ( $closure ) {
+ $prettyFunc = "$event closure";
+ } elseif( is_array( $callback ) ) {
+ if( is_object( $callback[0] ) ) {
+ $prettyClass = get_class( $callback[0] );
+ } else {
+ $prettyClass = strval( $callback[0] );
+ }
+ $prettyFunc = $prettyClass . '::' . strval( $callback[1] );
+ } else {
+ $prettyFunc = strval( $callback );
+ }
+ if ( $badhookmsg ) {
+ throw new MWException(
+ 'Detected bug in an extension! ' .
+ "Hook $prettyFunc has invalid call signature; " . $badhookmsg
+ );
+ } else {
+ throw new MWException(
+ 'Detected bug in an extension! ' .
+ "Hook $prettyFunc failed to return a value; " .
+ 'should return true to continue hook processing or false to abort.'
+ );
+ }
+ } elseif ( !$retval ) {
+ return false;
+ }
}
- wfProfileOut( $func );
- /* String return is an error; false return means stop processing. */
+ return true;
+ }
- if (is_string($retval)) {
- global $wgOut;
- $wgOut->showFatalError($retval);
- return false;
- } else if (!$retval) {
- return false;
+ /**
+ * This REALLY should be protected... but it's public for compatibility
+ *
+ * @param $errno int Unused
+ * @param $errstr String: error message
+ * @return Boolean: false
+ */
+ public static function hookErrorHandler( $errno, $errstr ) {
+ if ( strpos( $errstr, 'expected to be a reference, value given' ) !== false ) {
+ throw new MWHookException( $errstr );
}
+ return false;
}
-
- return true;
}
-?>
dépôts / lhc / web / wiklou.git / blobdiff