includes/Hooks.php

   1 <?php
   2 if ( ! defined( 'MEDIAWIKI' ) )
   3         die( -1 );
   4 /**
   5  * Hooks.php -- a tool for running hook functions
   6  * Copyright 2004, 2005 Evan Prodromou <evan@wikitravel.org>.
   7  *
   8  *  This program is free software; you can redistribute it and/or modify
   9  *  it under the terms of the GNU General Public License as published by
  10  *  the Free Software Foundation; either version 2 of the License, or
  11  *  (at your option) any later version.
  12  *
  13  *  This program is distributed in the hope that it will be useful,
  14  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  *  GNU General Public License for more details.
  17  *
  18  *  You should have received a copy of the GNU General Public License
  19  *  along with this program; if not, write to the Free Software
  20  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  21  *
  22  * @author Evan Prodromou <evan@wikitravel.org>
  23  * @package MediaWiki
  24  * @see hooks.txt
  25  */
  26
  27
  28 /**
  29  * Because programmers assign to $wgHooks, we need to be very
  30  * careful about its contents. So, there's a lot more error-checking
  31  * in here than would normally be necessary.
  32  */
  33 function wfRunHooks($event, $args = null) {
  34
  35         global $wgHooks;
  36         $fname = 'wfRunHooks';
  37         wfProfileIn( $fname );
  38
  39         if (!is_array($wgHooks)) {
  40                 wfDebugDieBacktrace("Global hooks array is not an array!\n");
  41                 wfProfileOut( $fname );
  42                 return false;
  43         }
  44
  45         if (!array_key_exists($event, $wgHooks)) {
  46                 wfProfileOut( $fname );
  47                 return true;
  48         }
  49
  50         if (!is_array($wgHooks[$event])) {
  51                 wfDebugDieBacktrace("Hooks array for event '$event' is not an array!\n");
  52                 wfProfileOut( $fname );
  53                 return false;
  54         }
  55
  56         foreach ($wgHooks[$event] as $index => $hook) {
  57
  58                 $object = NULL;
  59                 $method = NULL;
  60                 $func = NULL;
  61                 $data = NULL;
  62                 $have_data = false;
  63
  64                 /* $hook can be: a function, an object, an array of $function and $data,
  65                  * an array of just a function, an array of object and method, or an
  66                  * array of object, method, and data.
  67                  */
  68
  69                 if (is_array($hook)) {
  70                         if (count($hook) < 1) {
  71                                 wfDebugDieBacktrace("Empty array in hooks for " . $event . "\n");
  72                         } else if (is_object($hook[0])) {
  73                                 $object =& $wgHooks[$event][$index][0];
  74                                 if (count($hook) < 2) {
  75                                         $method = "on" . $event;
  76                                 } else {
  77                                         $method = $hook[1];
  78                                         if (count($hook) > 2) {
  79                                                 $data = $hook[2];
  80                                                 $have_data = true;
  81                                         }
  82                                 }
  83                         } else if (is_string($hook[0])) {
  84                                 $func = $hook[0];
  85                                 if (count($hook) > 1) {
  86                                         $data = $hook[1];
  87                                         $have_data = true;
  88                                 }
  89                         } else {
  90                                 wfDebugDieBacktrace("Unknown datatype in hooks for " . $event . "\n");
  91                         }
  92                 } else if (is_string($hook)) { # functions look like strings, too
  93                         $func = $hook;
  94                 } else if (is_object($hook)) {
  95                         $object =& $wgHooks[$event][$index];
  96                         $method = "on" . $event;
  97                 } else {
  98                         wfDebugDieBacktrace("Unknown datatype in hooks for " . $event . "\n");
  99                 }
 100
 101                 /* We put the first data element on, if needed. */
 102
 103                 if ($have_data) {
 104                         $hook_args = array_merge(array($data), $args);
 105                 } else {
 106                         $hook_args = $args;
 107                 }
 108
 109
 110                 if ( isset( $object ) ) {
 111                         $func = get_class( $object ) . '::' . $method;
 112                 }
 113
 114                 /* Call the hook. */
 115                 wfProfileIn( $func );
 116                 if( isset( $object ) ) {
 117                         $retval = call_user_func_array(array(&$object, $method), $hook_args);
 118                 } else {
 119                         $retval = call_user_func_array($func, $hook_args);
 120                 }
 121                 wfProfileOut( $func );
 122
 123                 /* String return is an error; false return means stop processing. */
 124
 125                 if (is_string($retval)) {
 126                         global $wgOut;
 127                         $wgOut->fatalError($retval);
 128                         wfProfileOut( $fname );
 129                         return false;
 130                 } else if (!$retval) {
 131                         wfProfileOut( $fname );
 132                         return false;
 133                 }
 134         }
 135
 136         wfProfileOut( $fname );
 137         return true;
 138 }
 139 ?>