diff options
Diffstat (limited to 'includes/Hooks.php')
| -rw-r--r-- | includes/Hooks.php | 384 |
1 files changed, 226 insertions, 158 deletions
diff --git a/includes/Hooks.php b/includes/Hooks.php index 168f4bd9..dd08d03b 100644 --- a/includes/Hooks.php +++ b/includes/Hooks.php @@ -4,203 +4,271 @@ * * 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> * @see hooks.txt * @file */ +class MWHookException extends MWException {} /** - * Call hook functions defined in $wgHooks + * Hooks class. * - * 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 + * Used to supersede $wgHooks, because globals are EVIL. */ -function wfRunHooks($event, $args = array()) { +class Hooks { - global $wgHooks; + protected static $handlers = array(); - // Return quickly in the most common case - if ( !isset( $wgHooks[$event] ) ) { - return true; + /** + * 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][] = $callback; } - if (!is_array($wgHooks)) { - throw new MWException("Global hooks array is not an array!\n"); + /** + * 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"); + /** + * 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; - $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"); - } else if ( is_object( $hook[0] ) ) { - $object = $wgHooks[$event][$index][0]; - if ( $object instanceof Closure ) { - $closure = true; - if ( count( $hook ) > 1 ) { + /** + * 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 + */ + 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 { - if ( count( $hook ) < 2 ) { - $method = "on" . $event; - } else { - $method = $hook[1]; - if ( count( $hook ) > 2 ) { - $data = $hook[2]; - $have_data = true; - } - } + 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 { - 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]; - if ( $object instanceof Closure ) { - $closure = true; + + /* We put the first data element on, if needed. */ + if ( $have_data ) { + $hook_args = array_merge( array( $data ), $args ); } else { - $method = "on" . $event; + $hook_args = $args; } - } else { - throw new MWException( "Unknown datatype in hooks for " . $event . "\n" ); - } - /* We put the first data element on, if needed. */ + if ( $closure ) { + $callback = $object; + $func = "hook-$event-closure"; + } elseif ( isset( $object ) ) { + $func = get_class( $object ) . '::' . $method; + $callback = array( $object, $method ); + } else { + $callback = $func; + } - if ( $have_data ) { - $hook_args = array_merge(array($data), $args); - } else { - $hook_args = $args; - } + // Run autoloader (workaround for call_user_func_array bug) + is_callable( $callback ); - if ( $closure ) { - $callback = $object; - $func = "hook-$event-closure"; - } elseif ( isset( $object ) ) { - $func = get_class( $object ) . '::' . $method; - $callback = array( $object, $method ); - } elseif ( false !== ( $pos = strpos( $func, '::' ) ) ) { - $callback = array( substr( $func, 0, $pos ), substr( $func, $pos + 2 ) ); - } else { - $callback = $func; - } + /** + * 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(); - // Run autoloader (workaround for call_user_func_array bug) - is_callable( $callback ); - - /* 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( 'hookErrorHandler' ); - wfProfileIn( $func ); - try { - $retval = call_user_func_array( $callback, $hook_args ); - } catch ( MWHookException $e ) { - $badhookmsg = $e->getMessage(); - } - wfProfileOut( $func ); - restore_error_handler(); - - /* String return is an error; false return means stop processing. */ - if ( is_string( $retval ) ) { - global $wgOut; - $wgOut->showFatalError( $retval ); - return false; - } elseif( $retval === null ) { - if ( $closure ) { - $prettyFunc = "$event closure"; - } elseif( is_array( $callback ) ) { - if( is_object( $callback[0] ) ) { - $prettyClass = get_class( $callback[0] ); + /* String return is an error; false return means stop processing. */ + if ( is_string( $retval ) ) { + global $wgOut; + $wgOut->showFatalError( $retval ); + return false; + } 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 { - $prettyClass = strval( $callback[0] ); + $prettyFunc = strval( $callback ); } - $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." ); + 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; } - } else if ( !$retval ) { - return false; } - } - return true; -} + return true; + } -function hookErrorHandler( $errno, $errstr ) { - if ( strpos( $errstr, 'expected to be a reference, value given' ) !== false ) { - throw new MWHookException( $errstr ); + /** + * This REALLY should be protected... but it's public for compatibility + * + * @param $errno 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 false; } - -class MWHookException extends MWException {}
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