includes/Title.php

   1 <?php
   2 /**
   3  * See title.txt
   4  * @file
   5  */
   6
   7 if ( !class_exists( 'UtfNormal' ) ) {
   8         require_once( dirname(__FILE__) . '/normal/UtfNormal.php' );
   9 }
  10
  11 define ( 'GAID_FOR_UPDATE', 1 );
  12
  13
  14 /**
  15  * Constants for pr_cascade bitfield
  16  */
  17 define( 'CASCADE', 1 );
  18
  19 /**
  20  * Represents a title within MediaWiki.
  21  * Optionally may contain an interwiki designation or namespace.
  22  * @note This class can fetch various kinds of data from the database;
  23  *       however, it does so inefficiently.
  24  */
  25 class Title {
  26         /** @name Static cache variables */
  27         //@{
  28         static private $titleCache=array();
  29         static private $interwikiCache=array();
  30         //@}
  31
  32         /**
  33          * Title::newFromText maintains a cache to avoid expensive re-normalization of
  34          * commonly used titles. On a batch operation this can become a memory leak
  35          * if not bounded. After hitting this many titles reset the cache.
  36          */
  37         const CACHE_MAX = 1000;
  38
  39
  40         /**
  41          * @name Private member variables
  42          * Please use the accessor functions instead.
  43          * @private
  44          */
  45         //@{
  46
  47         var $mTextform = '';              ///< Text form (spaces not underscores) of the main part
  48         var $mUrlform = '';               ///< URL-encoded form of the main part
  49         var $mDbkeyform = '';             ///< Main part with underscores
  50         var $mUserCaseDBKey;              ///< DB key with the initial letter in the case specified by the user
  51         var $mNamespace = NS_MAIN;        ///< Namespace index, i.e. one of the NS_xxxx constants
  52         var $mInterwiki = '';             ///< Interwiki prefix (or null string)
  53         var $mFragment;                   ///< Title fragment (i.e. the bit after the #)
  54         var $mArticleID = -1;             ///< Article ID, fetched from the link cache on demand
  55         var $mLatestID = false;           ///< ID of most recent revision
  56         var $mRestrictions = array();     ///< Array of groups allowed to edit this article
  57         var $mOldRestrictions = false;
  58         var $mCascadeRestriction;         ///< Cascade restrictions on this page to included templates and images?
  59         var $mRestrictionsExpiry = array();       ///< When do the restrictions on this page expire?
  60         var $mHasCascadingRestrictions;   ///< Are cascading restrictions in effect on this page?
  61         var $mCascadeSources;  ///< Where are the cascading restrictions coming from on this page?
  62         var $mRestrictionsLoaded = false; ///< Boolean for initialisation on demand
  63         var $mPrefixedText;               ///< Text form including namespace/interwiki, initialised on demand
  64         # Don't change the following default, NS_MAIN is hardcoded in several
  65         # places.  See bug 696.
  66         var $mDefaultNamespace = NS_MAIN; ///< Namespace index when there is no namespace
  67                                           # Zero except in {{transclusion}} tags
  68         var $mWatched = null;             ///< Is $wgUser watching this page? null if unfilled, accessed through userIsWatching()
  69         var $mLength = -1;                ///< The page length, 0 for special pages
  70         var $mRedirect = null;            ///< Is the article at this title a redirect?
  71         var $mNotificationTimestamp = array(); ///< Associative array of user ID -> timestamp/false
  72         var $mBacklinkCache = null; ///< Cache of links to this title
  73         //@}
  74
  75
  76         /**
  77          * Constructor
  78          * @private
  79          */
  80         /* private */ function __construct() {}
  81
  82         /**
  83          * Create a new Title from a prefixed DB key
  84          * @param $key \type{\string} The database key, which has underscores
  85          *      instead of spaces, possibly including namespace and
  86          *      interwiki prefixes
  87          * @return \type{Title} the new object, or NULL on an error
  88          */
  89         public static function newFromDBkey( $key ) {
  90                 $t = new Title();
  91                 $t->mDbkeyform = $key;
  92                 if( $t->secureAndSplit() )
  93                         return $t;
  94                 else
  95                         return NULL;
  96         }
  97
  98         /**
  99          * Create a new Title from text, such as what one would find in a link. De-
 100          * codes any HTML entities in the text.
 101          *
 102          * @param $text             string  The link text; spaces, prefixes, and an
 103          *   initial ':' indicating the main namespace are accepted.
 104          * @param $defaultNamespace int     The namespace to use if none is speci-
 105          *   fied by a prefix.  If you want to force a specific namespace even if
 106          *   $text might begin with a namespace prefix, use makeTitle() or
 107          *   makeTitleSafe().
 108          * @return Title  The new object, or null on an error.
 109          */
 110         public static function newFromText( $text, $defaultNamespace = NS_MAIN ) {
 111                 if( is_object( $text ) ) {
 112                         throw new MWException( 'Title::newFromText given an object' );
 113                 }
 114
 115                 /**
 116                  * Wiki pages often contain multiple links to the same page.
 117                  * Title normalization and parsing can become expensive on
 118                  * pages with many links, so we can save a little time by
 119                  * caching them.
 120                  *
 121                  * In theory these are value objects and won't get changed...
 122                  */
 123                 if( $defaultNamespace == NS_MAIN && isset( Title::$titleCache[$text] ) ) {
 124                         return Title::$titleCache[$text];
 125                 }
 126
 127                 /**
 128                  * Convert things like &eacute; &#257; or &#x3017; into real text...
 129                  */
 130                 $filteredText = Sanitizer::decodeCharReferences( $text );
 131
 132                 $t = new Title();
 133                 $t->mDbkeyform = str_replace( ' ', '_', $filteredText );
 134                 $t->mDefaultNamespace = $defaultNamespace;
 135
 136                 static $cachedcount = 0 ;
 137                 if( $t->secureAndSplit() ) {
 138                         if( $defaultNamespace == NS_MAIN ) {
 139                                 if( $cachedcount >= self::CACHE_MAX ) {
 140                                         # Avoid memory leaks on mass operations...
 141                                         Title::$titleCache = array();
 142                                         $cachedcount=0;
 143                                 }
 144                                 $cachedcount++;
 145                                 Title::$titleCache[$text] =& $t;
 146                         }
 147                         return $t;
 148                 } else {
 149                         $ret = NULL;
 150                         return $ret;
 151                 }
 152         }
 153
 154         /**
 155          * Create a new Title from URL-encoded text. Ensures that
 156          * the given title's length does not exceed the maximum.
 157          * @param $url \type{\string} the title, as might be taken from a URL
 158          * @return \type{Title} the new object, or NULL on an error
 159          */
 160         public static function newFromURL( $url ) {
 161                 global $wgLegalTitleChars;
 162                 $t = new Title();
 163
 164                 # For compatibility with old buggy URLs. "+" is usually not valid in titles,
 165                 # but some URLs used it as a space replacement and they still come
 166                 # from some external search tools.
 167                 if ( strpos( $wgLegalTitleChars, '+' ) === false ) {
 168                         $url = str_replace( '+', ' ', $url );
 169                 }
 170
 171                 $t->mDbkeyform = str_replace( ' ', '_', $url );
 172                 if( $t->secureAndSplit() ) {
 173                         return $t;
 174                 } else {
 175                         return NULL;
 176                 }
 177         }
 178
 179         /**
 180          * Create a new Title from an article ID
 181          *
 182          * @todo This is inefficiently implemented, the page row is requested
 183          *       but not used for anything else
 184          *
 185          * @param $id \type{\int} the page_id corresponding to the Title to create
 186          * @param $flags \type{\int} use GAID_FOR_UPDATE to use master
 187          * @return \type{Title} the new object, or NULL on an error
 188          */
 189         public static function newFromID( $id, $flags = 0 ) {
 190                 $fname = 'Title::newFromID';
 191                 $db = ($flags & GAID_FOR_UPDATE) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
 192                 $row = $db->selectRow( 'page', array( 'page_namespace', 'page_title' ),
 193                         array( 'page_id' => $id ), $fname );
 194                 if ( $row !== false ) {
 195                         $title = Title::makeTitle( $row->page_namespace, $row->page_title );
 196                 } else {
 197                         $title = NULL;
 198                 }
 199                 return $title;
 200         }
 201
 202         /**
 203          * Make an array of titles from an array of IDs
 204          * @param $ids \type{\arrayof{\int}} Array of IDs
 205          * @return \type{\arrayof{Title}} Array of Titles
 206          */
 207         public static function newFromIDs( $ids ) {
 208                 if ( !count( $ids ) ) {
 209                         return array();
 210                 }
 211                 $dbr = wfGetDB( DB_SLAVE );
 212                 $res = $dbr->select( 'page', array( 'page_namespace', 'page_title' ),
 213                         'page_id IN (' . $dbr->makeList( $ids ) . ')', __METHOD__ );
 214
 215                 $titles = array();
 216                 foreach( $res as $row ) {
 217                         $titles[] = Title::makeTitle( $row->page_namespace, $row->page_title );
 218                 }
 219                 return $titles;
 220         }
 221
 222         /**
 223          * Make a Title object from a DB row
 224          * @param $row \type{Row} (needs at least page_title,page_namespace)
 225          * @return \type{Title} corresponding Title
 226          */
 227         public static function newFromRow( $row ) {
 228                 $t = self::makeTitle( $row->page_namespace, $row->page_title );
 229
 230                 $t->mArticleID = isset($row->page_id) ? intval($row->page_id) : -1;
 231                 $t->mLength = isset($row->page_len) ? intval($row->page_len) : -1;
 232                 $t->mRedirect = isset($row->page_is_redirect) ? (bool)$row->page_is_redirect : NULL;
 233                 $t->mLatestID = isset($row->page_latest) ? $row->page_latest : false;
 234
 235                 return $t;
 236         }
 237
 238         /**
 239          * Create a new Title from a namespace index and a DB key.
 240          * It's assumed that $ns and $title are *valid*, for instance when
 241          * they came directly from the database or a special page name.
 242          * For convenience, spaces are converted to underscores so that
 243          * eg user_text fields can be used directly.
 244          *
 245          * @param $ns \type{\int} the namespace of the article
 246          * @param $title \type{\string} the unprefixed database key form
 247          * @param $fragment \type{\string} The link fragment (after the "#")
 248          * @return \type{Title} the new object
 249          */
 250         public static function &makeTitle( $ns, $title, $fragment = '' ) {
 251                 $t = new Title();
 252                 $t->mInterwiki = '';
 253                 $t->mFragment = $fragment;
 254                 $t->mNamespace = $ns = intval( $ns );
 255                 $t->mDbkeyform = str_replace( ' ', '_', $title );
 256                 $t->mArticleID = ( $ns >= 0 ) ? -1 : 0;
 257                 $t->mUrlform = wfUrlencode( $t->mDbkeyform );
 258                 $t->mTextform = str_replace( '_', ' ', $title );
 259                 return $t;
 260         }
 261
 262         /**
 263          * Create a new Title from a namespace index and a DB key.
 264          * The parameters will be checked for validity, which is a bit slower
 265          * than makeTitle() but safer for user-provided data.
 266          *
 267          * @param $ns \type{\int} the namespace of the article
 268          * @param $title \type{\string} the database key form
 269          * @param $fragment \type{\string} The link fragment (after the "#")
 270          * @return \type{Title} the new object, or NULL on an error
 271          */
 272         public static function makeTitleSafe( $ns, $title, $fragment = '' ) {
 273                 $t = new Title();
 274                 $t->mDbkeyform = Title::makeName( $ns, $title, $fragment );
 275                 if( $t->secureAndSplit() ) {
 276                         return $t;
 277                 } else {
 278                         return NULL;
 279                 }
 280         }
 281
 282         /**
 283          * Create a new Title for the Main Page
 284          * @return \type{Title} the new object
 285          */
 286         public static function newMainPage() {
 287                 $title = Title::newFromText( wfMsgForContent( 'mainpage' ) );
 288                 // Don't give fatal errors if the message is broken
 289                 if ( !$title ) {
 290                         $title = Title::newFromText( 'Main Page' );
 291                 }
 292                 return $title;
 293         }
 294
 295         /**
 296          * Extract a redirect destination from a string and return the
 297          * Title, or null if the text doesn't contain a valid redirect
 298          * This will only return the very next target, useful for
 299          * the redirect table and other checks that don't need full recursion
 300          *
 301          * @param $text \type{\string} Text with possible redirect
 302          * @return \type{Title} The corresponding Title
 303          */
 304         public static function newFromRedirect( $text ) {
 305                 return self::newFromRedirectInternal( $text );
 306         }
 307
 308         /**
 309          * Extract a redirect destination from a string and return the
 310          * Title, or null if the text doesn't contain a valid redirect
 311          * This will recurse down $wgMaxRedirects times or until a non-redirect target is hit
 312          * in order to provide (hopefully) the Title of the final destination instead of another redirect
 313          *
 314          * @param $text \type{\string} Text with possible redirect
 315          * @return \type{Title} The corresponding Title
 316          */
 317         public static function newFromRedirectRecurse( $text ) {
 318                 $titles = self::newFromRedirectArray( $text );
 319                 return $titles ? array_pop( $titles ) : null;
 320         }
 321
 322         /**
 323          * Extract a redirect destination from a string and return an
 324          * array of Titles, or null if the text doesn't contain a valid redirect
 325          * The last element in the array is the final destination after all redirects
 326          * have been resolved (up to $wgMaxRedirects times)
 327          *
 328          * @param $text \type{\string} Text with possible redirect
 329          * @return \type{\array} Array of Titles, with the destination last
 330          */
 331         public static function newFromRedirectArray( $text ) {
 332                 global $wgMaxRedirects;
 333                 // are redirects disabled?
 334                 if( $wgMaxRedirects < 1 )
 335                         return null;
 336                 $title = self::newFromRedirectInternal( $text );
 337                 if( is_null( $title ) )
 338                         return null;
 339                 // recursive check to follow double redirects
 340                 $recurse = $wgMaxRedirects;
 341                 $titles = array( $title );
 342                 while( --$recurse > 0 ) {
 343                         if( $title->isRedirect() ) {
 344                                 $article = new Article( $title, 0 );
 345                                 $newtitle = $article->getRedirectTarget();
 346                         } else {
 347                                 break;
 348                         }
 349                         // Redirects to some special pages are not permitted
 350                         if( $newtitle instanceOf Title && $newtitle->isValidRedirectTarget() ) {
 351                                 // the new title passes the checks, so make that our current title so that further recursion can be checked
 352                                 $title = $newtitle;
 353                                 $titles[] = $newtitle;
 354                         } else {
 355                                 break;
 356                         }
 357                 }
 358                 return $titles;
 359         }
 360
 361         /**
 362          * Really extract the redirect destination
 363          * Do not call this function directly, use one of the newFromRedirect* functions above
 364          *
 365          * @param $text \type{\string} Text with possible redirect
 366          * @return \type{Title} The corresponding Title
 367          */
 368         protected static function newFromRedirectInternal( $text ) {
 369                 $redir = MagicWord::get( 'redirect' );
 370                 $text = trim($text);
 371                 if( $redir->matchStartAndRemove( $text ) ) {
 372                         // Extract the first link and see if it's usable
 373                         // Ensure that it really does come directly after #REDIRECT
 374                         // Some older redirects included a colon, so don't freak about that!
 375                         $m = array();
 376                         if( preg_match( '!^\s*:?\s*\[{2}(.*?)(?:\|.*?)?\]{2}!', $text, $m ) ) {
 377                                 // Strip preceding colon used to "escape" categories, etc.
 378                                 // and URL-decode links
 379                                 if( strpos( $m[1], '%' ) !== false ) {
 380                                         // Match behavior of inline link parsing here;
 381                                         // don't interpret + as " " most of the time!
 382                                         // It might be safe to just use rawurldecode instead, though.
 383                                         $m[1] = urldecode( ltrim( $m[1], ':' ) );
 384                                 }
 385                                 $title = Title::newFromText( $m[1] );
 386                                 // If the title is a redirect to bad special pages or is invalid, return null
 387                                 if( !$title instanceof Title || !$title->isValidRedirectTarget() ) {
 388                                         return null;
 389                                 }
 390                                 return $title;
 391                         }
 392                 }
 393                 return null;
 394         }
 395
 396 #----------------------------------------------------------------------------
 397 #       Static functions
 398 #----------------------------------------------------------------------------
 399
 400         /**
 401          * Get the prefixed DB key associated with an ID
 402          * @param $id \type{\int} the page_id of the article
 403          * @return \type{Title} an object representing the article, or NULL
 404          *      if no such article was found
 405          */
 406         public static function nameOf( $id ) {
 407                 $dbr = wfGetDB( DB_SLAVE );
 408
 409                 $s = $dbr->selectRow( 'page',
 410                         array( 'page_namespace','page_title' ),
 411                         array( 'page_id' => $id ),
 412                         __METHOD__ );
 413                 if ( $s === false ) { return NULL; }
 414
 415                 $n = self::makeName( $s->page_namespace, $s->page_title );
 416                 return $n;
 417         }
 418
 419         /**
 420          * Get a regex character class describing the legal characters in a link
 421          * @return \type{\string} the list of characters, not delimited
 422          */
 423         public static function legalChars() {
 424                 global $wgLegalTitleChars;
 425                 return $wgLegalTitleChars;
 426         }
 427
 428         /**
 429          * Get a string representation of a title suitable for
 430          * including in a search index
 431          *
 432          * @param $ns \type{\int} a namespace index
 433          * @param $title \type{\string} text-form main part
 434          * @return \type{\string} a stripped-down title string ready for the
 435          *      search index
 436          */
 437         public static function indexTitle( $ns, $title ) {
 438                 global $wgContLang;
 439
 440                 $lc = SearchEngine::legalSearchChars() . '&#;';
 441                 $t = $wgContLang->stripForSearch( $title );
 442                 $t = preg_replace( "/[^{$lc}]+/", ' ', $t );
 443                 $t = $wgContLang->lc( $t );
 444
 445                 # Handle 's, s'
 446                 $t = preg_replace( "/([{$lc}]+)'s( |$)/", "\\1 \\1's ", $t );
 447                 $t = preg_replace( "/([{$lc}]+)s'( |$)/", "\\1s ", $t );
 448
 449                 $t = preg_replace( "/\\s+/", ' ', $t );
 450
 451                 if ( $ns == NS_FILE ) {
 452                         $t = preg_replace( "/ (png|gif|jpg|jpeg|ogg)$/", "", $t );
 453                 }
 454                 return trim( $t );
 455         }
 456
 457         /*
 458          * Make a prefixed DB key from a DB key and a namespace index
 459          * @param $ns \type{\int} numerical representation of the namespace
 460          * @param $title \type{\string} the DB key form the title
 461          * @param $fragment \type{\string} The link fragment (after the "#")
 462          * @return \type{\string} the prefixed form of the title
 463          */
 464         public static function makeName( $ns, $title, $fragment = '' ) {
 465                 global $wgContLang;
 466
 467                 $namespace = $wgContLang->getNsText( $ns );
 468                 $name = $namespace == '' ? $title : "$namespace:$title";
 469                 if ( strval( $fragment ) != '' ) {
 470                         $name .= '#' . $fragment;
 471                 }
 472                 return $name;
 473         }
 474
 475         /**
 476          * Returns the URL associated with an interwiki prefix
 477          * @param $key \type{\string} the interwiki prefix (e.g. "MeatBall")
 478          * @return \type{\string} the associated URL, containing "$1",
 479          *      which should be replaced by an article title
 480          * @static (arguably)
 481          * @deprecated See Interwiki class
 482          */
 483         public function getInterwikiLink( $key )  {
 484                 return Interwiki::fetch( $key )->getURL( );
 485         }
 486
 487         /**
 488          * Determine whether the object refers to a page within
 489          * this project.
 490          *
 491          * @return \type{\bool} TRUE if this is an in-project interwiki link
 492          *      or a wikilink, FALSE otherwise
 493          */
 494         public function isLocal() {
 495                 if ( $this->mInterwiki != '' ) {
 496                         return Interwiki::fetch( $this->mInterwiki )->isLocal();
 497                 } else {
 498                         return true;
 499                 }
 500         }
 501
 502         /**
 503          * Determine whether the object refers to a page within
 504          * this project and is transcludable.
 505          *
 506          * @return \type{\bool} TRUE if this is transcludable
 507          */
 508         public function isTrans() {
 509                 if ($this->mInterwiki == '')
 510                         return false;
 511
 512                 return Interwiki::fetch( $this->mInterwiki )->isTranscludable();
 513         }
 514
 515         /**
 516          * Escape a text fragment, say from a link, for a URL
 517          */
 518         static function escapeFragmentForURL( $fragment ) {
 519                 global $wgEnforceHtmlIds;
 520                 # Note that we don't urlencode the fragment.  urlencoded Unicode
 521                 # fragments appear not to work in IE (at least up to 7) or in at least
 522                 # one version of Opera 9.x.  The W3C validator, for one, doesn't seem
 523                 # to care if they aren't encoded.
 524                 return Sanitizer::escapeId( $fragment,
 525                         $wgEnforceHtmlIds ? 'noninitial' : 'xml' );
 526         }
 527
 528 #----------------------------------------------------------------------------
 529 #       Other stuff
 530 #----------------------------------------------------------------------------
 531
 532         /** Simple accessors */
 533         /**
 534          * Get the text form (spaces not underscores) of the main part
 535          * @return \type{\string} Main part of the title
 536          */
 537         public function getText() { return $this->mTextform; }
 538         /**
 539          * Get the URL-encoded form of the main part
 540          * @return \type{\string} Main part of the title, URL-encoded
 541          */
 542         public function getPartialURL() { return $this->mUrlform; }
 543         /**
 544          * Get the main part with underscores
 545          * @return \type{\string} Main part of the title, with underscores
 546          */
 547         public function getDBkey() { return $this->mDbkeyform; }
 548         /**
 549          * Get the namespace index, i.e.\ one of the NS_xxxx constants.
 550          * @return \type{\int} Namespace index
 551          */
 552         public function getNamespace() { return $this->mNamespace; }
 553         /**
 554          * Get the namespace text
 555          * @return \type{\string} Namespace text
 556          */
 557         public function getNsText() {
 558                 global $wgContLang, $wgCanonicalNamespaceNames;
 559
 560                 if ( '' != $this->mInterwiki ) {
 561                         // This probably shouldn't even happen. ohh man, oh yuck.
 562                         // But for interwiki transclusion it sometimes does.
 563                         // Shit. Shit shit shit.
 564                         //
 565                         // Use the canonical namespaces if possible to try to
 566                         // resolve a foreign namespace.
 567                         if( isset( $wgCanonicalNamespaceNames[$this->mNamespace] ) ) {
 568                                 return $wgCanonicalNamespaceNames[$this->mNamespace];
 569                         }
 570                 }
 571                 return $wgContLang->getNsText( $this->mNamespace );
 572         }
 573         /**
 574          * Get the DB key with the initial letter case as specified by the user
 575          * @return \type{\string} DB key
 576          */
 577         function getUserCaseDBKey() {
 578                 return $this->mUserCaseDBKey;
 579         }
 580         /**
 581          * Get the namespace text of the subject (rather than talk) page
 582          * @return \type{\string} Namespace text
 583          */
 584         public function getSubjectNsText() {
 585                 global $wgContLang;
 586                 return $wgContLang->getNsText( MWNamespace::getSubject( $this->mNamespace ) );
 587         }
 588         /**
 589          * Get the namespace text of the talk page
 590          * @return \type{\string} Namespace text
 591          */
 592         public function getTalkNsText() {
 593                 global $wgContLang;
 594                 return( $wgContLang->getNsText( MWNamespace::getTalk( $this->mNamespace ) ) );
 595         }
 596         /**
 597          * Could this title have a corresponding talk page?
 598          * @return \type{\bool} TRUE or FALSE
 599          */
 600         public function canTalk() {
 601                 return( MWNamespace::canTalk( $this->mNamespace ) );
 602         }
 603         /**
 604          * Get the interwiki prefix (or null string)
 605          * @return \type{\string} Interwiki prefix
 606          */
 607         public function getInterwiki() { return $this->mInterwiki; }
 608         /**
 609          * Get the Title fragment (i.e.\ the bit after the #) in text form
 610          * @return \type{\string} Title fragment
 611          */
 612         public function getFragment() { return $this->mFragment; }
 613         /**
 614          * Get the fragment in URL form, including the "#" character if there is one
 615          * @return \type{\string} Fragment in URL form
 616          */
 617         public function getFragmentForURL() {
 618                 if ( $this->mFragment == '' ) {
 619                         return '';
 620                 } else {
 621                         return '#' . Title::escapeFragmentForURL( $this->mFragment );
 622                 }
 623         }
 624         /**
 625          * Get the default namespace index, for when there is no namespace
 626          * @return \type{\int} Default namespace index
 627          */
 628         public function getDefaultNamespace() { return $this->mDefaultNamespace; }
 629
 630         /**
 631          * Get title for search index
 632          * @return \type{\string} a stripped-down title string ready for the
 633          *      search index
 634          */
 635         public function getIndexTitle() {
 636                 return Title::indexTitle( $this->mNamespace, $this->mTextform );
 637         }
 638
 639         /**
 640          * Get the prefixed database key form
 641          * @return \type{\string} the prefixed title, with underscores and
 642          *      any interwiki and namespace prefixes
 643          */
 644         public function getPrefixedDBkey() {
 645                 $s = $this->prefix( $this->mDbkeyform );
 646                 $s = str_replace( ' ', '_', $s );
 647                 return $s;
 648         }
 649
 650         /**
 651          * Get the prefixed title with spaces.
 652          * This is the form usually used for display
 653          * @return \type{\string} the prefixed title, with spaces
 654          */
 655         public function getPrefixedText() {
 656                 if ( empty( $this->mPrefixedText ) ) { // FIXME: bad usage of empty() ?
 657                         $s = $this->prefix( $this->mTextform );
 658                         $s = str_replace( '_', ' ', $s );
 659                         $this->mPrefixedText = $s;
 660                 }
 661                 return $this->mPrefixedText;
 662         }
 663
 664         /**
 665          * Get the prefixed title with spaces, plus any fragment
 666          * (part beginning with '#')
 667          * @return \type{\string} the prefixed title, with spaces and
 668          *      the fragment, including '#'
 669          */
 670         public function getFullText() {
 671                 $text = $this->getPrefixedText();
 672                 if( '' != $this->mFragment ) {
 673                         $text .= '#' . $this->mFragment;
 674                 }
 675                 return $text;
 676         }
 677
 678         /**
 679          * Get the base name, i.e. the leftmost parts before the /
 680          * @return \type{\string} Base name
 681          */
 682         public function getBaseText() {
 683                 if( !MWNamespace::hasSubpages( $this->mNamespace ) ) {
 684                         return $this->getText();
 685                 }
 686
 687                 $parts = explode( '/', $this->getText() );
 688                 # Don't discard the real title if there's no subpage involved
 689                 if( count( $parts ) > 1 )
 690                         unset( $parts[ count( $parts ) - 1 ] );
 691                 return implode( '/', $parts );
 692         }
 693
 694         /**
 695          * Get the lowest-level subpage name, i.e. the rightmost part after /
 696          * @return \type{\string} Subpage name
 697          */
 698         public function getSubpageText() {
 699                 if( !MWNamespace::hasSubpages( $this->mNamespace ) ) {
 700                         return( $this->mTextform );
 701                 }
 702                 $parts = explode( '/', $this->mTextform );
 703                 return( $parts[ count( $parts ) - 1 ] );
 704         }
 705
 706         /**
 707          * Get a URL-encoded form of the subpage text
 708          * @return \type{\string} URL-encoded subpage name
 709          */
 710         public function getSubpageUrlForm() {
 711                 $text = $this->getSubpageText();
 712                 $text = wfUrlencode( str_replace( ' ', '_', $text ) );
 713                 return( $text );
 714         }
 715
 716         /**
 717          * Get a URL-encoded title (not an actual URL) including interwiki
 718          * @return \type{\string} the URL-encoded form
 719          */
 720         public function getPrefixedURL() {
 721                 $s = $this->prefix( $this->mDbkeyform );
 722                 $s = wfUrlencode( str_replace( ' ', '_', $s ) );
 723                 return $s;
 724         }
 725
 726         /**
 727          * Get a real URL referring to this title, with interwiki link and
 728          * fragment
 729          *
 730          * @param $query \twotypes{\string,\array} an optional query string, not used for interwiki
 731          *   links. Can be specified as an associative array as well, e.g.,
 732          *   array( 'action' => 'edit' ) (keys and values will be URL-escaped).
 733          * @param $variant \type{\string} language variant of url (for sr, zh..)
 734          * @return \type{\string} the URL
 735          */
 736         public function getFullURL( $query = '', $variant = false ) {
 737                 global $wgContLang, $wgServer, $wgRequest;
 738
 739                 if( is_array( $query ) ) {
 740                         $query = wfArrayToCGI( $query );
 741                 }
 742
 743                 $interwiki = Interwiki::fetch( $this->mInterwiki );
 744                 if ( !$interwiki ) {
 745                         $url = $this->getLocalUrl( $query, $variant );
 746
 747                         // Ugly quick hack to avoid duplicate prefixes (bug 4571 etc)
 748                         // Correct fix would be to move the prepending elsewhere.
 749                         if ($wgRequest->getVal('action') != 'render') {
 750                                 $url = $wgServer . $url;
 751                         }
 752                 } else {
 753                         $baseUrl = $interwiki->getURL( );
 754
 755                         $namespace = wfUrlencode( $this->getNsText() );
 756                         if ( '' != $namespace ) {
 757                                 # Can this actually happen? Interwikis shouldn't be parsed.
 758                                 # Yes! It can in interwiki transclusion. But... it probably shouldn't.
 759                                 $namespace .= ':';
 760                         }
 761                         $url = str_replace( '$1', $namespace . $this->mUrlform, $baseUrl );
 762                         $url = wfAppendQuery( $url, $query );
 763                 }
 764
 765                 # Finally, add the fragment.
 766                 $url .= $this->getFragmentForURL();
 767
 768                 wfRunHooks( 'GetFullURL', array( &$this, &$url, $query ) );
 769                 return $url;
 770         }
 771
 772         /**
 773          * Get a URL with no fragment or server name.  If this page is generated
 774          * with action=render, $wgServer is prepended.
 775          * @param mixed $query an optional query string; if not specified,
 776          *       $wgArticlePath will be used.  Can be specified as an associative array
 777          *   as well, e.g., array( 'action' => 'edit' ) (keys and values will be
 778          *   URL-escaped).
 779          * @param $variant \type{\string} language variant of url (for sr, zh..)
 780          * @return \type{\string} the URL
 781          */
 782         public function getLocalURL( $query = '', $variant = false ) {
 783                 global $wgArticlePath, $wgScript, $wgServer, $wgRequest;
 784                 global $wgVariantArticlePath, $wgContLang, $wgUser;
 785
 786                 if( is_array( $query ) ) {
 787                         $query = wfArrayToCGI( $query );
 788                 }
 789
 790                 // internal links should point to same variant as current page (only anonymous users)
 791                 if($variant == false && $wgContLang->hasVariants() && !$wgUser->isLoggedIn()){
 792                         $pref = $wgContLang->getPreferredVariant(false);
 793                         if($pref != $wgContLang->getCode())
 794                                 $variant = $pref;
 795                 }
 796
 797                 if ( $this->isExternal() ) {
 798                         $url = $this->getFullURL();
 799                         if ( $query ) {
 800                                 // This is currently only used for edit section links in the
 801                                 // context of interwiki transclusion. In theory we should
 802                                 // append the query to the end of any existing query string,
 803                                 // but interwiki transclusion is already broken in that case.
 804                                 $url .= "?$query";
 805                         }
 806                 } else {
 807                         $dbkey = wfUrlencode( $this->getPrefixedDBkey() );
 808                         if ( $query == '' ) {
 809                                 if( $variant != false && $wgContLang->hasVariants() ) {
 810                                         if( $wgVariantArticlePath == false ) {
 811                                                 $variantArticlePath =  "$wgScript?title=$1&variant=$2"; // default
 812                                         } else {
 813                                                 $variantArticlePath = $wgVariantArticlePath;
 814                                         }
 815                                         $url = str_replace( '$2', urlencode( $variant ), $variantArticlePath );
 816                                         $url = str_replace( '$1', $dbkey, $url  );
 817                                 } else {
 818                                         $url = str_replace( '$1', $dbkey, $wgArticlePath );
 819                                 }
 820                         } else {
 821                                 global $wgActionPaths;
 822                                 $url = false;
 823                                 $matches = array();
 824                                 if( !empty( $wgActionPaths ) &&
 825                                         preg_match( '/^(.*&|)action=([^&]*)(&(.*)|)$/', $query, $matches ) )
 826                                 {
 827                                         $action = urldecode( $matches[2] );
 828                                         if( isset( $wgActionPaths[$action] ) ) {
 829                                                 $query = $matches[1];
 830                                                 if( isset( $matches[4] ) ) $query .= $matches[4];
 831                                                 $url = str_replace( '$1', $dbkey, $wgActionPaths[$action] );
 832                                                 if( $query != '' ) {
 833                                                         $url = wfAppendQuery( $url, $query );
 834                                                 }
 835                                         }
 836                                 }
 837                                 if ( $url === false ) {
 838                                         if ( $query == '-' ) {
 839                                                 $query = '';
 840                                         }
 841                                         $url = "{$wgScript}?title={$dbkey}&{$query}";
 842                                 }
 843                         }
 844
 845                         // FIXME: this causes breakage in various places when we
 846                         // actually expected a local URL and end up with dupe prefixes.
 847                         if ($wgRequest->getVal('action') == 'render') {
 848                                 $url = $wgServer . $url;
 849                         }
 850                 }
 851                 wfRunHooks( 'GetLocalURL', array( &$this, &$url, $query ) );
 852                 return $url;
 853         }
 854
 855         /**
 856          * Get a URL that's the simplest URL that will be valid to link, locally,
 857          * to the current Title.  It includes the fragment, but does not include
 858          * the server unless action=render is used (or the link is external).  If
 859          * there's a fragment but the prefixed text is empty, we just return a link
 860          * to the fragment.
 861          *
 862          * @param $query \type{\arrayof{\string}} An associative array of key => value pairs for the
 863          *   query string.  Keys and values will be escaped.
 864          * @param $variant \type{\string} Language variant of URL (for sr, zh..).  Ignored
 865          *   for external links.  Default is "false" (same variant as current page,
 866          *   for anonymous users).
 867          * @return \type{\string} the URL
 868          */
 869         public function getLinkUrl( $query = array(), $variant = false ) {
 870                 wfProfileIn( __METHOD__ );
 871                 if( !is_array( $query ) ) {
 872                         wfProfileOut( __METHOD__ );
 873                         throw new MWException( 'Title::getLinkUrl passed a non-array for '.
 874                         '$query' );
 875                 }
 876                 if( $this->isExternal() ) {
 877                         $ret = $this->getFullURL( $query );
 878                 } elseif( $this->getPrefixedText() === ''
 879                 and $this->getFragment() !== '' ) {
 880                         $ret = $this->getFragmentForURL();
 881                 } else {
 882                         $ret = $this->getLocalURL( $query, $variant )
 883                                 . $this->getFragmentForURL();
 884                 }
 885                 wfProfileOut( __METHOD__ );
 886                 return $ret;
 887         }
 888
 889         /**
 890          * Get an HTML-escaped version of the URL form, suitable for
 891          * using in a link, without a server name or fragment
 892          * @param $query \type{\string} an optional query string
 893          * @return \type{\string} the URL
 894          */
 895         public function escapeLocalURL( $query = '' ) {
 896                 return htmlspecialchars( $this->getLocalURL( $query ) );
 897         }
 898
 899         /**
 900          * Get an HTML-escaped version of the URL form, suitable for
 901          * using in a link, including the server name and fragment
 902          *
 903          * @param $query \type{\string} an optional query string
 904          * @return \type{\string} the URL
 905          */
 906         public function escapeFullURL( $query = '' ) {
 907                 return htmlspecialchars( $this->getFullURL( $query ) );
 908         }
 909
 910         /**
 911          * Get the URL form for an internal link.
 912          * - Used in various Squid-related code, in case we have a different
 913          * internal hostname for the server from the exposed one.
 914          *
 915          * @param $query \type{\string} an optional query string
 916          * @param $variant \type{\string} language variant of url (for sr, zh..)
 917          * @return \type{\string} the URL
 918          */
 919         public function getInternalURL( $query = '', $variant = false ) {
 920                 global $wgInternalServer;
 921                 $url = $wgInternalServer . $this->getLocalURL( $query, $variant );
 922                 wfRunHooks( 'GetInternalURL', array( &$this, &$url, $query ) );
 923                 return $url;
 924         }
 925
 926         /**
 927          * Get the edit URL for this Title
 928          * @return \type{\string} the URL, or a null string if this is an
 929          *      interwiki link
 930          */
 931         public function getEditURL() {
 932                 if ( '' != $this->mInterwiki ) { return ''; }
 933                 $s = $this->getLocalURL( 'action=edit' );
 934
 935                 return $s;
 936         }
 937
 938         /**
 939          * Get the HTML-escaped displayable text form.
 940          * Used for the title field in <a> tags.
 941          * @return \type{\string} the text, including any prefixes
 942          */
 943         public function getEscapedText() {
 944                 return htmlspecialchars( $this->getPrefixedText() );
 945         }
 946
 947         /**
 948          * Is this Title interwiki?
 949          * @return \type{\bool}
 950          */
 951         public function isExternal() { return ( '' != $this->mInterwiki ); }
 952
 953         /**
 954          * Is this page "semi-protected" - the *only* protection is autoconfirm?
 955          *
 956          * @param @action \type{\string} Action to check (default: edit)
 957          * @return \type{\bool}
 958          */
 959         public function isSemiProtected( $action = 'edit' ) {
 960                 if( $this->exists() ) {
 961                         $restrictions = $this->getRestrictions( $action );
 962                         if( count( $restrictions ) > 0 ) {
 963                                 foreach( $restrictions as $restriction ) {
 964                                         if( strtolower( $restriction ) != 'autoconfirmed' )
 965                                                 return false;
 966                                 }
 967                         } else {
 968                                 # Not protected
 969                                 return false;
 970                         }
 971                         return true;
 972                 } else {
 973                         # If it doesn't exist, it can't be protected
 974                         return false;
 975                 }
 976         }
 977
 978         /**
 979          * Does the title correspond to a protected article?
 980          * @param $what \type{\string} the action the page is protected from,
 981          * by default checks move and edit
 982          * @return \type{\bool}
 983          */
 984         public function isProtected( $action = '' ) {
 985                 global $wgRestrictionLevels, $wgRestrictionTypes;
 986
 987                 # Special pages have inherent protection
 988                 if( $this->getNamespace() == NS_SPECIAL )
 989                         return true;
 990
 991                 # Check regular protection levels
 992                 foreach( $wgRestrictionTypes as $type ){
 993                         if( $action == $type || $action == '' ) {
 994                                 $r = $this->getRestrictions( $type );
 995                                 foreach( $wgRestrictionLevels as $level ) {
 996                                         if( in_array( $level, $r ) && $level != '' ) {
 997                                                 return true;
 998                                         }
 999                                 }
1000                         }
1001                 }
1002
1003                 return false;
1004         }
1005
1006         /**
1007          * Is $wgUser watching this page?
1008          * @return \type{\bool}
1009          */
1010         public function userIsWatching() {
1011                 global $wgUser;
1012
1013                 if ( is_null( $this->mWatched ) ) {
1014                         if ( NS_SPECIAL == $this->mNamespace || !$wgUser->isLoggedIn()) {
1015                                 $this->mWatched = false;
1016                         } else {
1017                                 $this->mWatched = $wgUser->isWatched( $this );
1018                         }
1019                 }
1020                 return $this->mWatched;
1021         }
1022
1023         /**
1024          * Can $wgUser perform $action on this page?
1025          * This skips potentially expensive cascading permission checks.
1026          *
1027          * Suitable for use for nonessential UI controls in common cases, but
1028          * _not_ for functional access control.
1029          *
1030          * May provide false positives, but should never provide a false negative.
1031          *
1032          * @param $action \type{\string} action that permission needs to be checked for
1033          * @return \type{\bool}
1034          */
1035         public function quickUserCan( $action ) {
1036                 return $this->userCan( $action, false );
1037         }
1038
1039         /**
1040          * Determines if $wgUser is unable to edit this page because it has been protected
1041          * by $wgNamespaceProtection.
1042          *
1043          * @return \type{\bool}
1044          */
1045         public function isNamespaceProtected() {
1046                 global $wgNamespaceProtection, $wgUser;
1047                 if( isset( $wgNamespaceProtection[ $this->mNamespace ] ) ) {
1048                         foreach( (array)$wgNamespaceProtection[ $this->mNamespace ] as $right ) {
1049                                 if( $right != '' && !$wgUser->isAllowed( $right ) )
1050                                         return true;
1051                         }
1052                 }
1053                 return false;
1054         }
1055
1056         /**
1057          * Can $wgUser perform $action on this page?
1058          * @param $action \type{\string} action that permission needs to be checked for
1059          * @param $doExpensiveQueries \type{\bool} Set this to false to avoid doing unnecessary queries.
1060          * @return \type{\bool}
1061          */
1062         public function userCan( $action, $doExpensiveQueries = true ) {
1063                 global $wgUser;
1064                 return ($this->getUserPermissionsErrorsInternal( $action, $wgUser, $doExpensiveQueries, true ) === array());
1065         }
1066
1067         /**
1068          * Can $user perform $action on this page?
1069          *
1070          * FIXME: This *does not* check throttles (User::pingLimiter()).
1071          *
1072          * @param $action \type{\string}action that permission needs to be checked for
1073          * @param $user \type{User} user to check
1074          * @param $doExpensiveQueries \type{\bool} Set this to false to avoid doing unnecessary queries.
1075          * @param $ignoreErrors \type{\arrayof{\string}} Set this to a list of message keys whose corresponding errors may be ignored.
1076          * @return \type{\array} Array of arrays of the arguments to wfMsg to explain permissions problems.
1077          */
1078         public function getUserPermissionsErrors( $action, $user, $doExpensiveQueries = true, $ignoreErrors = array() ) {
1079                 if( !StubObject::isRealObject( $user ) ) {
1080                         //Since StubObject is always used on globals, we can unstub $wgUser here and set $user = $wgUser
1081                         global $wgUser;
1082                         $wgUser->_unstub( '', 5 );
1083                         $user = $wgUser;
1084                 }
1085                 $errors = $this->getUserPermissionsErrorsInternal( $action, $user, $doExpensiveQueries );
1086
1087                 global $wgContLang;
1088                 global $wgLang;
1089                 global $wgEmailConfirmToEdit;
1090
1091                 if ( $wgEmailConfirmToEdit && !$user->isEmailConfirmed() && $action != 'createaccount' ) {
1092                         $errors[] = array( 'confirmedittext' );
1093                 }
1094
1095                 // Edit blocks should not affect reading. Account creation blocks handled at userlogin.
1096                 if ( $action != 'read' && $action != 'createaccount' && $user->isBlockedFrom( $this ) ) {
1097                         $block = $user->mBlock;
1098
1099                         // This is from OutputPage::blockedPage
1100                         // Copied at r23888 by werdna
1101
1102                         $id = $user->blockedBy();
1103                         $reason = $user->blockedFor();
1104                         if( $reason == '' ) {
1105                                 $reason = wfMsg( 'blockednoreason' );
1106                         }
1107                         $ip = wfGetIP();
1108
1109                         if ( is_numeric( $id ) ) {
1110                                 $name = User::whoIs( $id );
1111                         } else {
1112                                 $name = $id;
1113                         }
1114
1115                         $link = '[[' . $wgContLang->getNsText( NS_USER ) . ":{$name}|{$name}]]";
1116                         $blockid = $block->mId;
1117                         $blockExpiry = $user->mBlock->mExpiry;
1118                         $blockTimestamp = $wgLang->timeanddate( wfTimestamp( TS_MW, $user->mBlock->mTimestamp ), true );
1119
1120                         if ( $blockExpiry == 'infinity' ) {
1121                                 // Entry in database (table ipblocks) is 'infinity' but 'ipboptions' uses 'infinite' or 'indefinite'
1122                                 $scBlockExpiryOptions = wfMsg( 'ipboptions' );
1123
1124                                 foreach ( explode( ',', $scBlockExpiryOptions ) as $option ) {
1125                                         if ( strpos( $option, ':' ) == false )
1126                                                 continue;
1127
1128                                         list ($show, $value) = explode( ":", $option );
1129
1130                                         if ( $value == 'infinite' || $value == 'indefinite' ) {
1131                                                 $blockExpiry = $show;
1132                                                 break;
1133                                         }
1134                                 }
1135                         } else {
1136                                 $blockExpiry = $wgLang->timeanddate( wfTimestamp( TS_MW, $blockExpiry ), true );
1137                         }
1138
1139                         $intended = $user->mBlock->mAddress;
1140
1141                         $errors[] = array( ($block->mAuto ? 'autoblockedtext' : 'blockedtext'), $link, $reason, $ip, $name,
1142                                 $blockid, $blockExpiry, $intended, $blockTimestamp );
1143                 }
1144
1145                 // Remove the errors being ignored.
1146
1147                 foreach( $errors as $index => $error ) {
1148                         $error_key = is_array($error) ? $error[0] : $error;
1149
1150                         if (in_array( $error_key, $ignoreErrors )) {
1151                                 unset($errors[$index]);
1152                         }
1153                 }
1154
1155                 return $errors;
1156         }
1157
1158         /**
1159          * Can $user perform $action on this page? This is an internal function,
1160          * which checks ONLY that previously checked by userCan (i.e. it leaves out
1161          * checks on wfReadOnly() and blocks)
1162          *
1163          * @param $action \type{\string} action that permission needs to be checked for
1164          * @param $user \type{User} user to check
1165          * @param $doExpensiveQueries \type{\bool} Set this to false to avoid doing unnecessary queries.
1166          * @param $short \type{\bool} Set this to true to stop after the first permission error.
1167          * @return \type{\array} Array of arrays of the arguments to wfMsg to explain permissions problems.
1168          */
1169         private function getUserPermissionsErrorsInternal( $action, $user, $doExpensiveQueries=true, $short=false ) {
1170                 wfProfileIn( __METHOD__ );
1171
1172                 $errors = array();
1173
1174                 // First stop is permissions checks, which fail most often, and which are easiest to test.
1175                 if ( $action == 'move' ) {
1176                         if( !$user->isAllowed( 'move-rootuserpages' )
1177                                         && $this->getNamespace() == NS_USER && !$this->isSubpage() )
1178                         {
1179                                 // Show user page-specific message only if the user can move other pages
1180                                 $errors[] = array( 'cant-move-user-page' );
1181                         }
1182
1183                         // Check if user is allowed to move files if it's a file
1184                         if( $this->getNamespace() == NS_FILE && !$user->isAllowed( 'movefile' ) ) {
1185                                 $errors[] = array( 'movenotallowedfile' );
1186                         }
1187
1188                         if( !$user->isAllowed( 'move' ) ) {
1189                                 // User can't move anything
1190                                 $errors[] = $user->isAnon() ? array ( 'movenologintext' ) : array ('movenotallowed');
1191                         }
1192                 } elseif ( $action == 'create' ) {
1193                         if( ( $this->isTalkPage() && !$user->isAllowed( 'createtalk' ) ) ||
1194                                 ( !$this->isTalkPage() && !$user->isAllowed( 'createpage' ) ) )
1195                         {
1196                                 $errors[] = $user->isAnon() ? array ('nocreatetext') : array ('nocreate-loggedin');
1197                         }
1198                 } elseif( $action == 'move-target' ) {
1199                         if( !$user->isAllowed( 'move' ) ) {
1200                                 // User can't move anything
1201                                 $errors[] = $user->isAnon() ? array ( 'movenologintext' ) : array ('movenotallowed');
1202                         } elseif( !$user->isAllowed( 'move-rootuserpages' )
1203                                 && $this->getNamespace() == NS_USER && !$this->isSubpage() )
1204                         {
1205                                 // Show user page-specific message only if the user can move other pages
1206                                 $errors[] = array( 'cant-move-to-user-page' );
1207                         }
1208                 } elseif( !$user->isAllowed( $action ) ) {
1209                         $return = null;
1210                         $groups = array_map( array( 'User', 'makeGroupLinkWiki' ),
1211                                 User::getGroupsWithPermission( $action ) );
1212                         if( $groups ) {
1213                                 $return = array( 'badaccess-groups',
1214                                         array( implode( ', ', $groups ), count( $groups ) ) );
1215                         } else {
1216                                 $return = array( "badaccess-group0" );
1217                         }
1218                         $errors[] = $return;
1219                 }
1220
1221                 # Short-circuit point
1222                 if( $short && count($errors) > 0 ) {
1223                         wfProfileOut( __METHOD__ );
1224                         return $errors;
1225                 }
1226
1227                 // Use getUserPermissionsErrors instead
1228                 if( !wfRunHooks( 'userCan', array( &$this, &$user, $action, &$result ) ) ) {
1229                         wfProfileOut( __METHOD__ );
1230                         return $result ? array() : array( array( 'badaccess-group0' ) );
1231                 }
1232                 // Check getUserPermissionsErrors hook
1233                 if( !wfRunHooks( 'getUserPermissionsErrors', array(&$this,&$user,$action,&$result) ) ) {
1234                         if( is_array($result) && count($result) && !is_array($result[0]) )
1235                                 $errors[] = $result; # A single array representing an error
1236                         else if( is_array($result) && is_array($result[0]) )
1237                                 $errors = array_merge( $errors, $result ); # A nested array representing multiple errors
1238                         else if( $result !== '' && is_string($result) )
1239                                 $errors[] = array($result); # A string representing a message-id
1240                         else if( $result === false )
1241                                 $errors[] = array('badaccess-group0'); # a generic "We don't want them to do that"
1242                 }
1243                 # Short-circuit point
1244                 if( $short && count($errors) > 0 ) {
1245                         wfProfileOut( __METHOD__ );
1246                         return $errors;
1247                 }
1248                 // Check getUserPermissionsErrorsExpensive hook
1249                 if( $doExpensiveQueries && !wfRunHooks( 'getUserPermissionsErrorsExpensive', array(&$this,&$user,$action,&$result) ) ) {
1250                         if( is_array($result) && count($result) && !is_array($result[0]) )
1251                                 $errors[] = $result; # A single array representing an error
1252                         else if( is_array($result) && is_array($result[0]) )
1253                                 $errors = array_merge( $errors, $result ); # A nested array representing multiple errors
1254                         else if( $result !== '' && is_string($result) )
1255                                 $errors[] = array($result); # A string representing a message-id
1256                         else if( $result === false )
1257                                 $errors[] = array('badaccess-group0'); # a generic "We don't want them to do that"
1258                 }
1259                 # Short-circuit point
1260                 if( $short && count($errors) > 0 ) {
1261                         wfProfileOut( __METHOD__ );
1262                         return $errors;
1263                 }
1264
1265                 # Only 'createaccount' and 'execute' can be performed on
1266                 # special pages, which don't actually exist in the DB.
1267                 $specialOKActions = array( 'createaccount', 'execute' );
1268                 if( NS_SPECIAL == $this->mNamespace && !in_array( $action, $specialOKActions) ) {
1269                         $errors[] = array('ns-specialprotected');
1270                 }
1271
1272                 # Check $wgNamespaceProtection for restricted namespaces
1273                 if( $this->isNamespaceProtected() ) {
1274                         $ns = $this->getNamespace() == NS_MAIN ?
1275                                 wfMsg( 'nstab-main' ) : $this->getNsText();
1276                         $errors[] = NS_MEDIAWIKI == $this->mNamespace ?
1277                                 array('protectedinterface') : array( 'namespaceprotected',  $ns );
1278                 }
1279
1280                 # Protect css/js subpages of user pages
1281                 # XXX: this might be better using restrictions
1282                 # XXX: Find a way to work around the php bug that prevents using $this->userCanEditCssJsSubpage() from working
1283                 if( $this->isCssJsSubpage() && !$user->isAllowed('editusercssjs')
1284                         && !preg_match('/^'.preg_quote($user->getName(), '/').'\//', $this->mTextform) )
1285                 {
1286                         $errors[] = array('customcssjsprotected');
1287                 }
1288
1289                 # Check against page_restrictions table requirements on this
1290                 # page. The user must possess all required rights for this action.
1291                 foreach( $this->getRestrictions($action) as $right ) {
1292                         // Backwards compatibility, rewrite sysop -> protect
1293                         if( $right == 'sysop' ) {
1294                                 $right = 'protect';
1295                         }
1296                         if( '' != $right && !$user->isAllowed( $right ) ) {
1297                                 // Users with 'editprotected' permission can edit protected pages
1298                                 if( $action=='edit' && $user->isAllowed( 'editprotected' ) ) {
1299                                         // Users with 'editprotected' permission cannot edit protected pages
1300                                         // with cascading option turned on.
1301                                         if( $this->mCascadeRestriction ) {
1302                                                 $errors[] = array( 'protectedpagetext', $right );
1303                                         }
1304                                 } else {
1305                                         $errors[] = array( 'protectedpagetext', $right );
1306                                 }
1307                         }
1308                 }
1309                 # Short-circuit point
1310                 if( $short && count($errors) > 0 ) {
1311                         wfProfileOut( __METHOD__ );
1312                         return $errors;
1313                 }
1314
1315                 if( $doExpensiveQueries && !$this->isCssJsSubpage() ) {
1316                         # We /could/ use the protection level on the source page, but it's fairly ugly
1317                         #  as we have to establish a precedence hierarchy for pages included by multiple
1318                         #  cascade-protected pages. So just restrict it to people with 'protect' permission,
1319                         #  as they could remove the protection anyway.
1320                         list( $cascadingSources, $restrictions ) = $this->getCascadeProtectionSources();
1321                         # Cascading protection depends on more than this page...
1322                         # Several cascading protected pages may include this page...
1323                         # Check each cascading level
1324                         # This is only for protection restrictions, not for all actions
1325                         if( $cascadingSources > 0 && isset($restrictions[$action]) ) {
1326                                 foreach( $restrictions[$action] as $right ) {
1327                                         $right = ( $right == 'sysop' ) ? 'protect' : $right;
1328                                         if( '' != $right && !$user->isAllowed( $right ) ) {
1329                                                 $pages = '';
1330                                                 foreach( $cascadingSources as $page )
1331                                                         $pages .= '* [[:' . $page->getPrefixedText() . "]]\n";
1332                                                 $errors[] = array( 'cascadeprotected', count( $cascadingSources ), $pages );
1333                                         }
1334                                 }
1335                         }
1336                 }
1337                 # Short-circuit point
1338                 if( $short && count($errors) > 0 ) {
1339                         wfProfileOut( __METHOD__ );
1340                         return $errors;
1341                 }
1342
1343                 if( $action == 'protect' ) {
1344                         if( $this->getUserPermissionsErrors('edit', $user) != array() ) {
1345                                 $errors[] = array( 'protect-cantedit' ); // If they can't edit, they shouldn't protect.
1346                         }
1347                 }
1348
1349                 if( $action == 'create' ) {
1350                         $title_protection = $this->getTitleProtection();
1351                         if( is_array($title_protection) ) {
1352                                 extract($title_protection); // is this extract() really needed?
1353
1354                                 if( $pt_create_perm == 'sysop' ) {
1355                                         $pt_create_perm = 'protect'; // B/C
1356                                 }
1357                                 if( $pt_create_perm == '' || !$user->isAllowed($pt_create_perm) ) {
1358                                         $errors[] = array( 'titleprotected', User::whoIs($pt_user), $pt_reason );
1359                                 }
1360                         }
1361                 } elseif( $action == 'move' ) {
1362                         // Check for immobile pages
1363                         if( !MWNamespace::isMovable( $this->getNamespace() ) ) {
1364                                 // Specific message for this case
1365                                 $errors[] = array( 'immobile-source-namespace', $this->getNsText() );
1366                         } elseif( !$this->isMovable() ) {
1367                                 // Less specific message for rarer cases
1368                                 $errors[] = array( 'immobile-page' );
1369                         }
1370                 } elseif( $action == 'move-target' ) {
1371                         if( !MWNamespace::isMovable( $this->getNamespace() ) ) {
1372                                 $errors[] = array( 'immobile-target-namespace', $this->getNsText() );
1373                         } elseif( !$this->isMovable() ) {
1374                                 $errors[] = array( 'immobile-target-page' );
1375                         }
1376                 }
1377
1378                 wfProfileOut( __METHOD__ );
1379                 return $errors;
1380         }
1381
1382         /**
1383          * Is this title subject to title protection?
1384          * @return \type{\mixed} An associative array representing any existent title
1385          *   protection, or false if there's none.
1386          */
1387         private function getTitleProtection() {
1388                 // Can't protect pages in special namespaces
1389                 if ( $this->getNamespace() < 0 ) {
1390                         return false;
1391                 }
1392
1393                 $dbr = wfGetDB( DB_SLAVE );
1394                 $res = $dbr->select( 'protected_titles', '*',
1395                         array( 'pt_namespace' => $this->getNamespace(), 'pt_title' => $this->getDBkey() ),
1396                         __METHOD__ );
1397
1398                 if ($row = $dbr->fetchRow( $res )) {
1399                         return $row;
1400                 } else {
1401                         return false;
1402                 }
1403         }
1404
1405         /**
1406          * Update the title protection status
1407          * @param $create_perm \type{\string} Permission required for creation
1408          * @param $reason \type{\string} Reason for protection
1409          * @param $expiry \type{\string} Expiry timestamp
1410          */
1411         public function updateTitleProtection( $create_perm, $reason, $expiry ) {
1412                 global $wgUser,$wgContLang;
1413
1414                 if ($create_perm == implode(',',$this->getRestrictions('create'))
1415                         && $expiry == $this->mRestrictionsExpiry['create']) {
1416                         // No change
1417                         return true;
1418                 }
1419
1420                 list ($namespace, $title) = array( $this->getNamespace(), $this->getDBkey() );
1421
1422                 $dbw = wfGetDB( DB_MASTER );
1423
1424                 $encodedExpiry = Block::encodeExpiry($expiry, $dbw );
1425
1426                 $expiry_description = '';
1427                 if ( $encodedExpiry != 'infinity' ) {
1428                         $expiry_description = ' (' . wfMsgForContent( 'protect-expiring', $wgContLang->timeanddate( $expiry ) , $wgContLang->date( $expiry ) , $wgContLang->time( $expiry ) ).')';
1429                 }
1430                 else {
1431                         $expiry_description .= ' (' . wfMsgForContent( 'protect-expiry-indefinite' ).')';
1432                 }
1433
1434                 # Update protection table
1435                 if ($create_perm != '' ) {
1436                         $dbw->replace( 'protected_titles', array(array('pt_namespace', 'pt_title')),
1437                                 array( 'pt_namespace' => $namespace, 'pt_title' => $title
1438                                         , 'pt_create_perm' => $create_perm
1439                                         , 'pt_timestamp' => Block::encodeExpiry(wfTimestampNow(), $dbw)
1440                                         , 'pt_expiry' => $encodedExpiry
1441                                         , 'pt_user' => $wgUser->getId(), 'pt_reason' => $reason ), __METHOD__  );
1442                 } else {
1443                         $dbw->delete( 'protected_titles', array( 'pt_namespace' => $namespace,
1444                                 'pt_title' => $title ), __METHOD__ );
1445                 }
1446                 # Update the protection log
1447                 $log = new LogPage( 'protect' );
1448
1449                 if( $create_perm ) {
1450                         $params = array("[create=$create_perm] $expiry_description",'');
1451                         $log->addEntry( $this->mRestrictions['create'] ? 'modify' : 'protect', $this, trim( $reason ), $params );
1452                 } else {
1453                         $log->addEntry( 'unprotect', $this, $reason );
1454                 }
1455
1456                 return true;
1457         }
1458
1459         /**
1460          * Remove any title protection due to page existing
1461          */
1462         public function deleteTitleProtection() {
1463                 $dbw = wfGetDB( DB_MASTER );
1464
1465                 $dbw->delete( 'protected_titles',
1466                         array( 'pt_namespace' => $this->getNamespace(), 'pt_title' => $this->getDBkey() ),
1467                         __METHOD__ );
1468         }
1469
1470         /**
1471          * Can $wgUser edit this page?
1472          * @return \type{\bool} TRUE or FALSE
1473          * @deprecated use userCan('edit')
1474          */
1475         public function userCanEdit( $doExpensiveQueries = true ) {
1476                 return $this->userCan( 'edit', $doExpensiveQueries );
1477         }
1478
1479         /**
1480          * Can $wgUser create this page?
1481          * @return \type{\bool} TRUE or FALSE
1482          * @deprecated use userCan('create')
1483          */
1484         public function userCanCreate( $doExpensiveQueries = true ) {
1485                 return $this->userCan( 'create', $doExpensiveQueries );
1486         }
1487
1488         /**
1489          * Can $wgUser move this page?
1490          * @return \type{\bool} TRUE or FALSE
1491          * @deprecated use userCan('move')
1492          */
1493         public function userCanMove( $doExpensiveQueries = true ) {
1494                 return $this->userCan( 'move', $doExpensiveQueries );
1495         }
1496
1497         /**
1498          * Would anybody with sufficient privileges be able to move this page?
1499          * Some pages just aren't movable.
1500          *
1501          * @return \type{\bool} TRUE or FALSE
1502          */
1503         public function isMovable() {
1504                 return MWNamespace::isMovable( $this->getNamespace() ) && $this->getInterwiki() == '';
1505         }
1506
1507         /**
1508          * Can $wgUser read this page?
1509          * @return \type{\bool} TRUE or FALSE
1510          * @todo fold these checks into userCan()
1511          */
1512         public function userCanRead() {
1513                 global $wgUser, $wgGroupPermissions;
1514
1515                 $result = null;
1516                 wfRunHooks( 'userCan', array( &$this, &$wgUser, 'read', &$result ) );
1517                 if ( $result !== null ) {
1518                         return $result;
1519                 }
1520
1521                 # Shortcut for public wikis, allows skipping quite a bit of code
1522                 if ( !empty( $wgGroupPermissions['*']['read'] ) )
1523                         return true;
1524
1525                 if( $wgUser->isAllowed( 'read' ) ) {
1526                         return true;
1527                 } else {
1528                         global $wgWhitelistRead;
1529
1530                         /**
1531                          * Always grant access to the login page.
1532                          * Even anons need to be able to log in.
1533                         */
1534                         if( $this->isSpecial( 'Userlogin' ) || $this->isSpecial( 'Resetpass' ) ) {
1535                                 return true;
1536                         }
1537
1538                         /**
1539                          * Bail out if there isn't whitelist
1540                          */
1541                         if( !is_array($wgWhitelistRead) ) {
1542                                 return false;
1543                         }
1544
1545                         /**
1546                          * Check for explicit whitelisting
1547                          */
1548                         $name = $this->getPrefixedText();
1549                         $dbName = $this->getPrefixedDBKey();
1550                         // Check with and without underscores
1551                         if( in_array($name,$wgWhitelistRead,true) || in_array($dbName,$wgWhitelistRead,true) )
1552                                 return true;
1553
1554                         /**
1555                          * Old settings might have the title prefixed with
1556                          * a colon for main-namespace pages
1557                          */
1558                         if( $this->getNamespace() == NS_MAIN ) {
1559                                 if( in_array( ':' . $name, $wgWhitelistRead ) )
1560                                         return true;
1561                         }
1562
1563                         /**
1564                          * If it's a special page, ditch the subpage bit
1565                          * and check again
1566                          */
1567                         if( $this->getNamespace() == NS_SPECIAL ) {
1568                                 $name = $this->getDBkey();
1569                                 list( $name, /* $subpage */) = SpecialPage::resolveAliasWithSubpage( $name );
1570                                 if ( $name === false ) {
1571                                         # Invalid special page, but we show standard login required message
1572                                         return false;
1573                                 }
1574
1575                                 $pure = SpecialPage::getTitleFor( $name )->getPrefixedText();
1576                                 if( in_array( $pure, $wgWhitelistRead, true ) )
1577                                         return true;
1578                         }
1579
1580                 }
1581                 return false;
1582         }
1583
1584         /**
1585          * Is this a talk page of some sort?
1586          * @return \type{\bool} TRUE or FALSE
1587          */
1588         public function isTalkPage() {
1589                 return MWNamespace::isTalk( $this->getNamespace() );
1590         }
1591
1592         /**
1593          * Is this a subpage?
1594          * @return \type{\bool} TRUE or FALSE
1595          */
1596         public function isSubpage() {
1597                 return MWNamespace::hasSubpages( $this->mNamespace )
1598                         ? strpos( $this->getText(), '/' ) !== false
1599                         : false;
1600         }
1601
1602         /**
1603          * Does this have subpages?  (Warning, usually requires an extra DB query.)
1604          * @return \type{\bool} TRUE or FALSE
1605          */
1606         public function hasSubpages() {
1607                 if( !MWNamespace::hasSubpages( $this->mNamespace ) ) {
1608                         # Duh
1609                         return false;
1610                 }
1611
1612                 # We dynamically add a member variable for the purpose of this method
1613                 # alone to cache the result.  There's no point in having it hanging
1614                 # around uninitialized in every Title object; therefore we only add it
1615                 # if needed and don't declare it statically.
1616                 if( isset( $this->mHasSubpages ) ) {
1617                         return $this->mHasSubpages;
1618                 }
1619
1620                 $subpages = $this->getSubpages( 1 );
1621                 if( $subpages instanceof TitleArray )
1622                         return $this->mHasSubpages = (bool)$subpages->count();
1623                 return $this->mHasSubpages = false;
1624         }
1625
1626         /**
1627          * Get all subpages of this page.
1628          * @param $limit Maximum number of subpages to fetch; -1 for no limit
1629          * @return mixed TitleArray, or empty array if this page's namespace
1630          *  doesn't allow subpages
1631          */
1632         public function getSubpages( $limit = -1 ) {
1633                 if( !MWNamespace::hasSubpages( $this->getNamespace() ) )
1634                         return array();
1635
1636                 $dbr = wfGetDB( DB_SLAVE );
1637                 $conds['page_namespace'] = $this->getNamespace();
1638                 $conds[] = 'page_title LIKE ' . $dbr->addQuotes(
1639                                 $dbr->escapeLike( $this->getDBkey() ) . '/%' );
1640                 $options = array();
1641                 if( $limit > -1 )
1642                         $options['LIMIT'] = $limit;
1643                 return $this->mSubpages = TitleArray::newFromResult(
1644                         $dbr->select( 'page',
1645                                 array( 'page_id', 'page_namespace', 'page_title' ),
1646                                 $conds,
1647                                 __METHOD__,
1648                                 $options
1649                         )
1650                 );
1651         }
1652
1653         /**
1654          * Could this page contain custom CSS or JavaScript, based
1655          * on the title?
1656          *
1657          * @return \type{\bool} TRUE or FALSE
1658          */
1659         public function isCssOrJsPage() {
1660                 return $this->mNamespace == NS_MEDIAWIKI
1661                         && preg_match( '!\.(?:css|js)$!u', $this->mTextform ) > 0;
1662         }
1663
1664         /**
1665          * Is this a .css or .js subpage of a user page?
1666          * @return \type{\bool} TRUE or FALSE
1667          */
1668         public function isCssJsSubpage() {
1669                 return ( NS_USER == $this->mNamespace and preg_match("/\\/.*\\.(?:css|js)$/", $this->mTextform ) );
1670         }
1671         /**
1672          * Is this a *valid* .css or .js subpage of a user page?
1673          * Check that the corresponding skin exists
1674          * @return \type{\bool} TRUE or FALSE
1675          */
1676         public function isValidCssJsSubpage() {
1677                 if ( $this->isCssJsSubpage() ) {
1678                         $skinNames = Skin::getSkinNames();
1679                         return array_key_exists( $this->getSkinFromCssJsSubpage(), $skinNames );
1680                 } else {
1681                         return false;
1682                 }
1683         }
1684         /**
1685          * Trim down a .css or .js subpage title to get the corresponding skin name
1686          */
1687         public function getSkinFromCssJsSubpage() {
1688                 $subpage = explode( '/', $this->mTextform );
1689                 $subpage = $subpage[ count( $subpage ) - 1 ];
1690                 return( str_replace( array( '.css', '.js' ), array( '', '' ), $subpage ) );
1691         }
1692         /**
1693          * Is this a .css subpage of a user page?
1694          * @return \type{\bool} TRUE or FALSE
1695          */
1696         public function isCssSubpage() {
1697                 return ( NS_USER == $this->mNamespace && preg_match("/\\/.*\\.css$/", $this->mTextform ) );
1698         }
1699         /**
1700          * Is this a .js subpage of a user page?
1701          * @return \type{\bool} TRUE or FALSE
1702          */
1703         public function isJsSubpage() {
1704                 return ( NS_USER == $this->mNamespace && preg_match("/\\/.*\\.js$/", $this->mTextform ) );
1705         }
1706         /**
1707          * Protect css/js subpages of user pages: can $wgUser edit
1708          * this page?
1709          *
1710          * @return \type{\bool} TRUE or FALSE
1711          * @todo XXX: this might be better using restrictions
1712          */
1713         public function userCanEditCssJsSubpage() {
1714                 global $wgUser;
1715                 return ( $wgUser->isAllowed('editusercssjs') || preg_match('/^'.preg_quote($wgUser->getName(), '/').'\//', $this->mTextform) );
1716         }
1717
1718         /**
1719          * Cascading protection: Return true if cascading restrictions apply to this page, false if not.
1720          *
1721          * @return \type{\bool} If the page is subject to cascading restrictions.
1722          */
1723         public function isCascadeProtected() {
1724                 list( $sources, /* $restrictions */ ) = $this->getCascadeProtectionSources( false );
1725                 return ( $sources > 0 );
1726         }
1727
1728         /**
1729          * Cascading protection: Get the source of any cascading restrictions on this page.
1730          *
1731          * @param $get_pages \type{\bool} Whether or not to retrieve the actual pages that the restrictions have come from.
1732          * @return \type{\arrayof{mixed title array, restriction array}} Array of the Title objects of the pages from
1733          *         which cascading restrictions have come, false for none, or true if such restrictions exist, but $get_pages was not set.
1734          *         The restriction array is an array of each type, each of which contains an array of unique groups.
1735          */
1736         public function getCascadeProtectionSources( $get_pages = true ) {
1737                 global $wgRestrictionTypes;
1738
1739                 # Define our dimension of restrictions types
1740                 $pagerestrictions = array();
1741                 foreach( $wgRestrictionTypes as $action )
1742                         $pagerestrictions[$action] = array();
1743
1744                 if ( isset( $this->mCascadeSources ) && $get_pages ) {
1745                         return array( $this->mCascadeSources, $this->mCascadingRestrictions );
1746                 } else if ( isset( $this->mHasCascadingRestrictions ) && !$get_pages ) {
1747                         return array( $this->mHasCascadingRestrictions, $pagerestrictions );
1748                 }
1749
1750                 wfProfileIn( __METHOD__ );
1751
1752                 $dbr = wfGetDB( DB_SLAVE );
1753
1754                 if ( $this->getNamespace() == NS_FILE ) {
1755                         $tables = array ('imagelinks', 'page_restrictions');
1756                         $where_clauses = array(
1757                                 'il_to' => $this->getDBkey(),
1758                                 'il_from=pr_page',
1759                                 'pr_cascade' => 1 );
1760                 } else {
1761                         $tables = array ('templatelinks', 'page_restrictions');
1762                         $where_clauses = array(
1763                                 'tl_namespace' => $this->getNamespace(),
1764                                 'tl_title' => $this->getDBkey(),
1765                                 'tl_from=pr_page',
1766                                 'pr_cascade' => 1 );
1767                 }
1768
1769                 if ( $get_pages ) {
1770                         $cols = array('pr_page', 'page_namespace', 'page_title', 'pr_expiry', 'pr_type', 'pr_level' );
1771                         $where_clauses[] = 'page_id=pr_page';
1772                         $tables[] = 'page';
1773                 } else {
1774                         $cols = array( 'pr_expiry' );
1775                 }
1776
1777                 $res = $dbr->select( $tables, $cols, $where_clauses, __METHOD__ );
1778
1779                 $sources = $get_pages ? array() : false;
1780                 $now = wfTimestampNow();
1781                 $purgeExpired = false;
1782
1783                 foreach( $res as $row ) {
1784                         $expiry = Block::decodeExpiry( $row->pr_expiry );
1785                         if( $expiry > $now ) {
1786                                 if ($get_pages) {
1787                                         $page_id = $row->pr_page;
1788                                         $page_ns = $row->page_namespace;
1789                                         $page_title = $row->page_title;
1790                                         $sources[$page_id] = Title::makeTitle($page_ns, $page_title);
1791                                         # Add groups needed for each restriction type if its not already there
1792                                         # Make sure this restriction type still exists
1793                                         if ( isset($pagerestrictions[$row->pr_type]) && !in_array($row->pr_level, $pagerestrictions[$row->pr_type]) ) {
1794                                                 $pagerestrictions[$row->pr_type][]=$row->pr_level;
1795                                         }
1796                                 } else {
1797                                         $sources = true;
1798                                 }
1799                         } else {
1800                                 // Trigger lazy purge of expired restrictions from the db
1801                                 $purgeExpired = true;
1802                         }
1803                 }
1804                 if( $purgeExpired ) {
1805                         Title::purgeExpiredRestrictions();
1806                 }
1807
1808                 wfProfileOut( __METHOD__ );
1809
1810                 if ( $get_pages ) {
1811                         $this->mCascadeSources = $sources;
1812                         $this->mCascadingRestrictions = $pagerestrictions;
1813                 } else {
1814                         $this->mHasCascadingRestrictions = $sources;
1815                 }
1816                 return array( $sources, $pagerestrictions );
1817         }
1818
1819         function areRestrictionsCascading() {
1820                 if (!$this->mRestrictionsLoaded) {
1821                         $this->loadRestrictions();
1822                 }
1823
1824                 return $this->mCascadeRestriction;
1825         }
1826
1827         /**
1828          * Loads a string into mRestrictions array
1829          * @param $res \type{Resource} restrictions as an SQL result.
1830          */
1831         private function loadRestrictionsFromRow( $res, $oldFashionedRestrictions = NULL ) {
1832                 global $wgRestrictionTypes;
1833                 $dbr = wfGetDB( DB_SLAVE );
1834
1835                 foreach( $wgRestrictionTypes as $type ){
1836                         $this->mRestrictions[$type] = array();
1837                         $this->mRestrictionsExpiry[$type] = Block::decodeExpiry('');
1838                 }
1839
1840                 $this->mCascadeRestriction = false;
1841
1842                 # Backwards-compatibility: also load the restrictions from the page record (old format).
1843
1844                 if ( $oldFashionedRestrictions === NULL ) {
1845                         $oldFashionedRestrictions = $dbr->selectField( 'page', 'page_restrictions',
1846                                 array( 'page_id' => $this->getArticleId() ), __METHOD__ );
1847                 }
1848
1849                 if ($oldFashionedRestrictions != '') {
1850
1851                         foreach( explode( ':', trim( $oldFashionedRestrictions ) ) as $restrict ) {
1852                                 $temp = explode( '=', trim( $restrict ) );
1853                                 if(count($temp) == 1) {
1854                                         // old old format should be treated as edit/move restriction
1855                                         $this->mRestrictions['edit'] = explode( ',', trim( $temp[0] ) );
1856                                         $this->mRestrictions['move'] = explode( ',', trim( $temp[0] ) );
1857                                 } else {
1858                                         $this->mRestrictions[$temp[0]] = explode( ',', trim( $temp[1] ) );
1859                                 }
1860                         }
1861
1862                         $this->mOldRestrictions = true;
1863
1864                 }
1865
1866                 if( $dbr->numRows( $res ) ) {
1867                         # Current system - load second to make them override.
1868                         $now = wfTimestampNow();
1869                         $purgeExpired = false;
1870
1871                         foreach( $res as $row ) {
1872                                 # Cycle through all the restrictions.
1873
1874                                 // Don't take care of restrictions types that aren't in $wgRestrictionTypes
1875                                 if( !in_array( $row->pr_type, $wgRestrictionTypes ) )
1876                                         continue;
1877
1878                                 // This code should be refactored, now that it's being used more generally,
1879                                 // But I don't really see any harm in leaving it in Block for now -werdna
1880                                 $expiry = Block::decodeExpiry( $row->pr_expiry );
1881
1882                                 // Only apply the restrictions if they haven't expired!
1883                                 if ( !$expiry || $expiry > $now ) {
1884                                         $this->mRestrictionsExpiry[$row->pr_type] = $expiry;
1885                                         $this->mRestrictions[$row->pr_type] = explode( ',', trim( $row->pr_level ) );
1886
1887                                         $this->mCascadeRestriction |= $row->pr_cascade;
1888                                 } else {
1889                                         // Trigger a lazy purge of expired restrictions
1890                                         $purgeExpired = true;
1891                                 }
1892                         }
1893
1894                         if( $purgeExpired ) {
1895                                 Title::purgeExpiredRestrictions();
1896                         }
1897                 }
1898
1899                 $this->mRestrictionsLoaded = true;
1900         }
1901
1902         /**
1903          * Load restrictions from the page_restrictions table
1904          */
1905         public function loadRestrictions( $oldFashionedRestrictions = NULL ) {
1906                 if( !$this->mRestrictionsLoaded ) {
1907                         if ($this->exists()) {
1908                                 $dbr = wfGetDB( DB_SLAVE );
1909
1910                                 $res = $dbr->select( 'page_restrictions', '*',
1911                                         array ( 'pr_page' => $this->getArticleId() ), __METHOD__ );
1912
1913                                 $this->loadRestrictionsFromRow( $res, $oldFashionedRestrictions );
1914                         } else {
1915                                 $title_protection = $this->getTitleProtection();
1916
1917                                 if (is_array($title_protection)) {
1918                                         extract($title_protection);
1919
1920                                         $now = wfTimestampNow();
1921                                         $expiry = Block::decodeExpiry($pt_expiry);
1922
1923                                         if (!$expiry || $expiry > $now) {
1924                                                 // Apply the restrictions
1925                                                 $this->mRestrictionsExpiry['create'] = $expiry;
1926                                                 $this->mRestrictions['create'] = explode(',', trim($pt_create_perm) );
1927                                         } else { // Get rid of the old restrictions
1928                                                 Title::purgeExpiredRestrictions();
1929                                         }
1930                                 } else {
1931                                         $this->mRestrictionsExpiry['create'] = Block::decodeExpiry('');
1932                                 }
1933                                 $this->mRestrictionsLoaded = true;
1934                         }
1935                 }
1936         }
1937
1938         /**
1939          * Purge expired restrictions from the page_restrictions table
1940          */
1941         static function purgeExpiredRestrictions() {
1942                 $dbw = wfGetDB( DB_MASTER );
1943                 $dbw->delete( 'page_restrictions',
1944                         array( 'pr_expiry < ' . $dbw->addQuotes( $dbw->timestamp() ) ),
1945                         __METHOD__ );
1946
1947                 $dbw->delete( 'protected_titles',
1948                         array( 'pt_expiry < ' . $dbw->addQuotes( $dbw->timestamp() ) ),
1949                         __METHOD__ );
1950         }
1951
1952         /**
1953          * Accessor/initialisation for mRestrictions
1954          *
1955          * @param $action \type{\string} action that permission needs to be checked for
1956          * @return \type{\arrayof{\string}} the array of groups allowed to edit this article
1957          */
1958         public function getRestrictions( $action ) {
1959                 if( !$this->mRestrictionsLoaded ) {
1960                         $this->loadRestrictions();
1961                 }
1962                 return isset( $this->mRestrictions[$action] )
1963                                 ? $this->mRestrictions[$action]
1964                                 : array();
1965         }
1966
1967         /**
1968          * Get the expiry time for the restriction against a given action
1969          * @return 14-char timestamp, or 'infinity' if the page is protected forever
1970          * or not protected at all, or false if the action is not recognised.
1971          */
1972         public function getRestrictionExpiry( $action ) {
1973                 if( !$this->mRestrictionsLoaded ) {
1974                         $this->loadRestrictions();
1975                 }
1976                 return isset( $this->mRestrictionsExpiry[$action] ) ? $this->mRestrictionsExpiry[$action] : false;
1977         }
1978
1979         /**
1980          * Is there a version of this page in the deletion archive?
1981          * @return \type{\int} the number of archived revisions
1982          */
1983         public function isDeleted() {
1984                 $fname = 'Title::isDeleted';
1985                 if ( $this->getNamespace() < 0 ) {
1986                         $n = 0;
1987                 } else {
1988                         $dbr = wfGetDB( DB_SLAVE );
1989                         $n = $dbr->selectField( 'archive', 'COUNT(*)', array( 'ar_namespace' => $this->getNamespace(),
1990                                 'ar_title' => $this->getDBkey() ), $fname );
1991                         if( $this->getNamespace() == NS_FILE ) {
1992                                 $n += $dbr->selectField( 'filearchive', 'COUNT(*)',
1993                                         array( 'fa_name' => $this->getDBkey() ), $fname );
1994                         }
1995                 }
1996                 return (int)$n;
1997         }
1998
1999         /**
2000          * Get the article ID for this Title from the link cache,
2001          * adding it if necessary
2002          * @param $flags \type{\int} a bit field; may be GAID_FOR_UPDATE to select
2003          *      for update
2004          * @return \type{\int} the ID
2005          */
2006         public function getArticleID( $flags = 0 ) {
2007                 if( $this->getNamespace() < 0 ) {
2008                         return $this->mArticleID = 0;
2009                 }
2010                 $linkCache = LinkCache::singleton();
2011                 if( $flags & GAID_FOR_UPDATE ) {
2012                         $oldUpdate = $linkCache->forUpdate( true );
2013                         $linkCache->clearLink( $this );
2014                         $this->mArticleID = $linkCache->addLinkObj( $this );
2015                         $linkCache->forUpdate( $oldUpdate );
2016                 } else {
2017                         if( -1 == $this->mArticleID ) {
2018                                 $this->mArticleID = $linkCache->addLinkObj( $this );
2019                         }
2020                 }
2021                 return $this->mArticleID;
2022         }
2023
2024         /**
2025          * Is this an article that is a redirect page?
2026          * Uses link cache, adding it if necessary
2027          * @param $flags \type{\int} a bit field; may be GAID_FOR_UPDATE to select for update
2028          * @return \type{\bool}
2029          */
2030         public function isRedirect( $flags = 0 ) {
2031                 if( !is_null($this->mRedirect) )
2032                         return $this->mRedirect;
2033                 # Calling getArticleID() loads the field from cache as needed
2034                 if( !$this->getArticleID($flags) ) {
2035                         return $this->mRedirect = false;
2036                 }
2037                 $linkCache = LinkCache::singleton();
2038                 $this->mRedirect = (bool)$linkCache->getGoodLinkFieldObj( $this, 'redirect' );
2039
2040                 return $this->mRedirect;
2041         }
2042
2043         /**
2044          * What is the length of this page?
2045          * Uses link cache, adding it if necessary
2046          * @param $flags \type{\int} a bit field; may be GAID_FOR_UPDATE to select for update
2047          * @return \type{\bool}
2048          */
2049         public function getLength( $flags = 0 ) {
2050                 if( $this->mLength != -1 )
2051                         return $this->mLength;
2052                 # Calling getArticleID() loads the field from cache as needed
2053                 if( !$this->getArticleID($flags) ) {
2054                         return $this->mLength = 0;
2055                 }
2056                 $linkCache = LinkCache::singleton();
2057                 $this->mLength = intval( $linkCache->getGoodLinkFieldObj( $this, 'length' ) );
2058
2059                 return $this->mLength;
2060         }
2061
2062         /**
2063          * What is the page_latest field for this page?
2064          * @param $flags \type{\int} a bit field; may be GAID_FOR_UPDATE to select for update
2065          * @return \type{\int}
2066          */
2067         public function getLatestRevID( $flags = 0 ) {
2068                 if( $this->mLatestID !== false )
2069                         return $this->mLatestID;
2070
2071                 $db = ($flags & GAID_FOR_UPDATE) ? wfGetDB(DB_MASTER) : wfGetDB(DB_SLAVE);
2072                 $this->mLatestID = $db->selectField( 'page', 'page_latest', $this->pageCond(), __METHOD__ );
2073                 return $this->mLatestID;
2074         }
2075
2076         /**
2077          * This clears some fields in this object, and clears any associated
2078          * keys in the "bad links" section of the link cache.
2079          *
2080          * - This is called from Article::insertNewArticle() to allow
2081          * loading of the new page_id. It's also called from
2082          * Article::doDeleteArticle()
2083          *
2084          * @param $newid \type{\int} the new Article ID
2085          */
2086         public function resetArticleID( $newid ) {
2087                 $linkCache = LinkCache::singleton();
2088                 $linkCache->clearBadLink( $this->getPrefixedDBkey() );
2089
2090                 if ( 0 == $newid ) { $this->mArticleID = -1; }
2091                 else { $this->mArticleID = $newid; }
2092                 $this->mRestrictionsLoaded = false;
2093                 $this->mRestrictions = array();
2094         }
2095
2096         /**
2097          * Updates page_touched for this page; called from LinksUpdate.php
2098          * @return \type{\bool} true if the update succeded
2099          */
2100         public function invalidateCache() {
2101                 if( wfReadOnly() ) {
2102                         return;
2103                 }
2104                 $dbw = wfGetDB( DB_MASTER );
2105                 $success = $dbw->update( 'page',
2106                         array( 'page_touched' => $dbw->timestamp() ),
2107                         $this->pageCond(),
2108                         __METHOD__
2109                 );
2110                 HTMLFileCache::clearFileCache( $this );
2111                 return $success;
2112         }
2113
2114         /**
2115          * Prefix some arbitrary text with the namespace or interwiki prefix
2116          * of this object
2117          *
2118          * @param $name \type{\string} the text
2119          * @return \type{\string} the prefixed text
2120          * @private
2121          */
2122         /* private */ function prefix( $name ) {
2123                 $p = '';
2124                 if ( '' != $this->mInterwiki ) {
2125                         $p = $this->mInterwiki . ':';
2126                 }
2127                 if ( 0 != $this->mNamespace ) {
2128                         $p .= $this->getNsText() . ':';
2129                 }
2130                 return $p . $name;
2131         }
2132
2133         /**
2134          * Secure and split - main initialisation function for this object
2135          *
2136          * Assumes that mDbkeyform has been set, and is urldecoded
2137          * and uses underscores, but not otherwise munged.  This function
2138          * removes illegal characters, splits off the interwiki and
2139          * namespace prefixes, sets the other forms, and canonicalizes
2140          * everything.
2141          * @return \type{\bool} true on success
2142          */
2143         private function secureAndSplit() {
2144                 global $wgContLang, $wgLocalInterwiki, $wgCapitalLinks;
2145
2146                 # Initialisation
2147                 static $rxTc = false;
2148                 if( !$rxTc ) {
2149                         # Matching titles will be held as illegal.
2150                         $rxTc = '/' .
2151                                 # Any character not allowed is forbidden...
2152                                 '[^' . Title::legalChars() . ']' .
2153                                 # URL percent encoding sequences interfere with the ability
2154                                 # to round-trip titles -- you can't link to them consistently.
2155                                 '|%[0-9A-Fa-f]{2}' .
2156                                 # XML/HTML character references produce similar issues.
2157                                 '|&[A-Za-z0-9\x80-\xff]+;' .
2158                                 '|&#[0-9]+;' .
2159                                 '|&#x[0-9A-Fa-f]+;' .
2160                                 '/S';
2161                 }
2162
2163                 $this->mInterwiki = $this->mFragment = '';
2164                 $this->mNamespace = $this->mDefaultNamespace; # Usually NS_MAIN
2165
2166                 $dbkey = $this->mDbkeyform;
2167
2168                 # Strip Unicode bidi override characters.
2169                 # Sometimes they slip into cut-n-pasted page titles, where the
2170                 # override chars get included in list displays.
2171                 $dbkey = preg_replace( '/\xE2\x80[\x8E\x8F\xAA-\xAE]/S', '', $dbkey );
2172
2173                 # Clean up whitespace
2174                 #
2175                 $dbkey = preg_replace( '/[ _]+/', '_', $dbkey );
2176                 $dbkey = trim( $dbkey, '_' );
2177
2178                 if ( '' == $dbkey ) {
2179                         return false;
2180                 }
2181
2182                 if( false !== strpos( $dbkey, UTF8_REPLACEMENT ) ) {
2183                         # Contained illegal UTF-8 sequences or forbidden Unicode chars.
2184                         return false;
2185                 }
2186
2187                 $this->mDbkeyform = $dbkey;
2188
2189                 # Initial colon indicates main namespace rather than specified default
2190                 # but should not create invalid {ns,title} pairs such as {0,Project:Foo}
2191                 if ( ':' == $dbkey{0} ) {
2192                         $this->mNamespace = NS_MAIN;
2193                         $dbkey = substr( $dbkey, 1 ); # remove the colon but continue processing
2194                         $dbkey = trim( $dbkey, '_' ); # remove any subsequent whitespace
2195                 }
2196
2197                 # Namespace or interwiki prefix
2198                 $firstPass = true;
2199                 $prefixRegexp = "/^(.+?)_*:_*(.*)$/S";
2200                 do {
2201                         $m = array();
2202                         if ( preg_match( $prefixRegexp, $dbkey, $m ) ) {
2203                                 $p = $m[1];
2204                                 if ( $ns = $wgContLang->getNsIndex( $p ) ) {
2205                                         # Ordinary namespace
2206                                         $dbkey = $m[2];
2207                                         $this->mNamespace = $ns;
2208                                         # For Talk:X pages, check if X has a "namespace" prefix
2209                                         if( $ns == NS_TALK && preg_match( $prefixRegexp, $dbkey, $x ) ) {
2210                                                 if( $wgContLang->getNsIndex( $x[1] ) )
2211                                                         return false; # Disallow Talk:File:x type titles...
2212                                                 else if( Interwiki::isValidInterwiki( $x[1] ) )
2213                                                         return false; # Disallow Talk:Interwiki:x type titles...
2214                                         }
2215                                 } elseif( Interwiki::isValidInterwiki( $p ) ) {
2216                                         if( !$firstPass ) {
2217                                                 # Can't make a local interwiki link to an interwiki link.
2218                                                 # That's just crazy!
2219                                                 return false;
2220                                         }
2221
2222                                         # Interwiki link
2223                                         $dbkey = $m[2];
2224                                         $this->mInterwiki = $wgContLang->lc( $p );
2225
2226                                         # Redundant interwiki prefix to the local wiki
2227                                         if ( 0 == strcasecmp( $this->mInterwiki, $wgLocalInterwiki ) ) {
2228                                                 if( $dbkey == '' ) {
2229                                                         # Can't have an empty self-link
2230                                                         return false;
2231                                                 }
2232                                                 $this->mInterwiki = '';
2233                                                 $firstPass = false;
2234                                                 # Do another namespace split...
2235                                                 continue;
2236                                         }
2237
2238                                         # If there's an initial colon after the interwiki, that also
2239                                         # resets the default namespace
2240                                         if ( $dbkey !== '' && $dbkey[0] == ':' ) {
2241                                                 $this->mNamespace = NS_MAIN;
2242                                                 $dbkey = substr( $dbkey, 1 );
2243                                         }
2244                                 }
2245                                 # If there's no recognized interwiki or namespace,
2246                                 # then let the colon expression be part of the title.
2247                         }
2248                         break;
2249                 } while( true );
2250
2251                 # We already know that some pages won't be in the database!
2252                 #
2253                 if ( '' != $this->mInterwiki || NS_SPECIAL == $this->mNamespace ) {
2254                         $this->mArticleID = 0;
2255                 }
2256                 $fragment = strstr( $dbkey, '#' );
2257                 if ( false !== $fragment ) {
2258                         $this->setFragment( $fragment );
2259                         $dbkey = substr( $dbkey, 0, strlen( $dbkey ) - strlen( $fragment ) );
2260                         # remove whitespace again: prevents "Foo_bar_#"
2261                         # becoming "Foo_bar_"
2262                         $dbkey = preg_replace( '/_*$/', '', $dbkey );
2263                 }
2264
2265                 # Reject illegal characters.
2266                 #
2267                 if( preg_match( $rxTc, $dbkey ) ) {
2268                         return false;
2269                 }
2270
2271                 /**
2272                  * Pages with "/./" or "/../" appearing in the URLs will often be un-
2273                  * reachable due to the way web browsers deal with 'relative' URLs.
2274                  * Also, they conflict with subpage syntax.  Forbid them explicitly.
2275                  */
2276                 if ( strpos( $dbkey, '.' ) !== false &&
2277                      ( $dbkey === '.' || $dbkey === '..' ||
2278                        strpos( $dbkey, './' ) === 0  ||
2279                        strpos( $dbkey, '../' ) === 0 ||
2280                        strpos( $dbkey, '/./' ) !== false ||
2281                        strpos( $dbkey, '/../' ) !== false  ||
2282                        substr( $dbkey, -2 ) == '/.' ||
2283                        substr( $dbkey, -3 ) == '/..' ) )
2284                 {
2285                         return false;
2286                 }
2287
2288                 /**
2289                  * Magic tilde sequences? Nu-uh!
2290                  */
2291                 if( strpos( $dbkey, '~~~' ) !== false ) {
2292                         return false;
2293                 }
2294
2295                 /**
2296                  * Limit the size of titles to 255 bytes.
2297                  * This is typically the size of the underlying database field.
2298                  * We make an exception for special pages, which don't need to be stored
2299                  * in the database, and may edge over 255 bytes due to subpage syntax
2300                  * for long titles, e.g. [[Special:Block/Long name]]
2301                  */
2302                 if ( ( $this->mNamespace != NS_SPECIAL && strlen( $dbkey ) > 255 ) ||
2303                   strlen( $dbkey ) > 512 )
2304                 {
2305                         return false;
2306                 }
2307
2308                 /**
2309                  * Normally, all wiki links are forced to have
2310                  * an initial capital letter so [[foo]] and [[Foo]]
2311                  * point to the same place.
2312                  *
2313                  * Don't force it for interwikis, since the other
2314                  * site might be case-sensitive.
2315                  */
2316                 $this->mUserCaseDBKey = $dbkey;
2317                 if( $wgCapitalLinks && $this->mInterwiki == '') {
2318                         $dbkey = $wgContLang->ucfirst( $dbkey );
2319                 }
2320
2321                 /**
2322                  * Can't make a link to a namespace alone...
2323                  * "empty" local links can only be self-links
2324                  * with a fragment identifier.
2325                  */
2326                 if( $dbkey == '' &&
2327                         $this->mInterwiki == '' &&
2328                         $this->mNamespace != NS_MAIN ) {
2329                         return false;
2330                 }
2331                 // Allow IPv6 usernames to start with '::' by canonicalizing IPv6 titles.
2332                 // IP names are not allowed for accounts, and can only be referring to
2333                 // edits from the IP. Given '::' abbreviations and caps/lowercaps,
2334                 // there are numerous ways to present the same IP. Having sp:contribs scan
2335                 // them all is silly and having some show the edits and others not is
2336                 // inconsistent. Same for talk/userpages. Keep them normalized instead.
2337                 $dbkey = ($this->mNamespace == NS_USER || $this->mNamespace == NS_USER_TALK) ?
2338                         IP::sanitizeIP( $dbkey ) : $dbkey;
2339                 // Any remaining initial :s are illegal.
2340                 if ( $dbkey !== '' && ':' == $dbkey{0} ) {
2341                         return false;
2342                 }
2343
2344                 # Fill fields
2345                 $this->mDbkeyform = $dbkey;
2346                 $this->mUrlform = wfUrlencode( $dbkey );
2347
2348                 $this->mTextform = str_replace( '_', ' ', $dbkey );
2349
2350                 return true;
2351         }
2352
2353         /**
2354          * Set the fragment for this title. Removes the first character from the
2355          * specified fragment before setting, so it assumes you're passing it with
2356          * an initial "#".
2357          *
2358          * Deprecated for public use, use Title::makeTitle() with fragment parameter.
2359          * Still in active use privately.
2360          *
2361          * @param $fragment \type{\string} text
2362          */
2363         public function setFragment( $fragment ) {
2364                 $this->mFragment = str_replace( '_', ' ', substr( $fragment, 1 ) );
2365         }
2366
2367         /**
2368          * Get a Title object associated with the talk page of this article
2369          * @return \type{Title} the object for the talk page
2370          */
2371         public function getTalkPage() {
2372                 return Title::makeTitle( MWNamespace::getTalk( $this->getNamespace() ), $this->getDBkey() );
2373         }
2374
2375         /**
2376          * Get a title object associated with the subject page of this
2377          * talk page
2378          *
2379          * @return \type{Title} the object for the subject page
2380          */
2381         public function getSubjectPage() {
2382                 // Is this the same title?
2383                 $subjectNS = MWNamespace::getSubject( $this->getNamespace() );
2384                 if( $this->getNamespace() == $subjectNS ) {
2385                         return $this;
2386                 }
2387                 return Title::makeTitle( $subjectNS, $this->getDBkey() );
2388         }
2389
2390         /**
2391          * Get an array of Title objects linking to this Title
2392          * Also stores the IDs in the link cache.
2393          *
2394          * WARNING: do not use this function on arbitrary user-supplied titles!
2395          * On heavily-used templates it will max out the memory.
2396          *
2397          * @param array $options may be FOR UPDATE
2398          * @return \type{\arrayof{Title}} the Title objects linking here
2399          */
2400         public function getLinksTo( $options = array(), $table = 'pagelinks', $prefix = 'pl' ) {
2401                 $linkCache = LinkCache::singleton();
2402
2403                 if ( count( $options ) > 0 ) {
2404                         $db = wfGetDB( DB_MASTER );
2405                 } else {
2406                         $db = wfGetDB( DB_SLAVE );
2407                 }
2408
2409                 $res = $db->select( array( 'page', $table ),
2410                         array( 'page_namespace', 'page_title', 'page_id', 'page_len', 'page_is_redirect' ),
2411                         array(
2412                                 "{$prefix}_from=page_id",
2413                                 "{$prefix}_namespace" => $this->getNamespace(),
2414                                 "{$prefix}_title"     => $this->getDBkey() ),
2415                         __METHOD__,
2416                         $options );
2417
2418                 $retVal = array();
2419                 if ( $db->numRows( $res ) ) {
2420                         foreach( $res as $row ) {
2421                                 if ( $titleObj = Title::makeTitle( $row->page_namespace, $row->page_title ) ) {
2422                                         $linkCache->addGoodLinkObj( $row->page_id, $titleObj, $row->page_len, $row->page_is_redirect );
2423                                         $retVal[] = $titleObj;
2424                                 }
2425                         }
2426                 }
2427                 $db->freeResult( $res );
2428                 return $retVal;
2429         }
2430
2431         /**
2432          * Get an array of Title objects using this Title as a template
2433          * Also stores the IDs in the link cache.
2434          *
2435          * WARNING: do not use this function on arbitrary user-supplied titles!
2436          * On heavily-used templates it will max out the memory.
2437          *
2438          * @param array $options may be FOR UPDATE
2439          * @return \type{\arrayof{Title}} the Title objects linking here
2440          */
2441         public function getTemplateLinksTo( $options = array() ) {
2442                 return $this->getLinksTo( $options, 'templatelinks', 'tl' );
2443         }
2444
2445         /**
2446          * Get an array of Title objects referring to non-existent articles linked from this page
2447          *
2448          * @todo check if needed (used only in SpecialBrokenRedirects.php, and should use redirect table in this case)
2449          * @return \type{\arrayof{Title}} the Title objects
2450          */
2451         public function getBrokenLinksFrom() {
2452                 if ( $this->getArticleId() == 0 ) {
2453                         # All links from article ID 0 are false positives
2454                         return array();
2455                 }
2456
2457                 $dbr = wfGetDB( DB_SLAVE );
2458                 $res = $dbr->select(
2459                         array( 'page', 'pagelinks' ),
2460                         array( 'pl_namespace', 'pl_title' ),
2461                         array(
2462                                 'pl_from' => $this->getArticleId(),
2463                                 'page_namespace IS NULL'
2464                         ),
2465                         __METHOD__, array(),
2466                         array(
2467                                 'page' => array(
2468                                         'LEFT JOIN',
2469                                         array( 'pl_namespace=page_namespace', 'pl_title=page_title' )
2470                                 )
2471                         )
2472                 );
2473
2474                 $retVal = array();
2475                 foreach( $res as $row ) {
2476                         $retVal[] = Title::makeTitle( $row->pl_namespace, $row->pl_title );
2477                 }
2478                 return $retVal;
2479         }
2480
2481
2482         /**
2483          * Get a list of URLs to purge from the Squid cache when this
2484          * page changes
2485          *
2486          * @return \type{\arrayof{\string}} the URLs
2487          */
2488         public function getSquidURLs() {
2489                 global $wgContLang;
2490
2491                 $urls = array(
2492                         $this->getInternalURL(),
2493                         $this->getInternalURL( 'action=history' )
2494                 );
2495
2496                 // purge variant urls as well
2497                 if($wgContLang->hasVariants()){
2498                         $variants = $wgContLang->getVariants();
2499                         foreach($variants as $vCode){
2500                                 if($vCode==$wgContLang->getCode()) continue; // we don't want default variant
2501                                 $urls[] = $this->getInternalURL('',$vCode);
2502                         }
2503                 }
2504
2505                 return $urls;
2506         }
2507
2508         /**
2509          * Purge all applicable Squid URLs
2510          */
2511         public function purgeSquid() {
2512                 global $wgUseSquid;
2513                 if ( $wgUseSquid ) {
2514                         $urls = $this->getSquidURLs();
2515                         $u = new SquidUpdate( $urls );
2516                         $u->doUpdate();
2517                 }
2518         }
2519
2520         /**
2521          * Move this page without authentication
2522          * @param &$nt \type{Title} the new page Title
2523          */
2524         public function moveNoAuth( &$nt ) {
2525                 return $this->moveTo( $nt, false );
2526         }
2527
2528         /**
2529          * Check whether a given move operation would be valid.
2530          * Returns true if ok, or a getUserPermissionsErrors()-like array otherwise
2531          * @param &$nt \type{Title} the new title
2532          * @param $auth \type{\bool} indicates whether $wgUser's permissions
2533          *      should be checked
2534          * @param $reason \type{\string} is the log summary of the move, used for spam checking
2535          * @return \type{\mixed} True on success, getUserPermissionsErrors()-like array on failure
2536          */
2537         public function isValidMoveOperation( &$nt, $auth = true, $reason = '' ) {
2538                 global $wgUser;
2539
2540                 $errors = array();
2541                 if( !$nt ) {
2542                         // Normally we'd add this to $errors, but we'll get
2543                         // lots of syntax errors if $nt is not an object
2544                         return array(array('badtitletext'));
2545                 }
2546                 if( $this->equals( $nt ) ) {
2547                         $errors[] = array('selfmove');
2548                 }
2549                 if( !$this->isMovable() ) {
2550                         $errors[] = array( 'immobile-source-namespace', $this->getNsText() );
2551                 }
2552                 if ( $nt->getInterwiki() != '' ) {
2553                         $errors[] = array( 'immobile-target-namespace-iw' );
2554                 }
2555                 if ( !$nt->isMovable() ) {
2556                         $errors[] = array('immobile-target-namespace', $nt->getNsText() );
2557                 }
2558
2559                 $oldid = $this->getArticleID();
2560                 $newid = $nt->getArticleID();
2561
2562                 if ( strlen( $nt->getDBkey() ) < 1 ) {
2563                         $errors[] = array('articleexists');
2564                 }
2565                 if ( ( '' == $this->getDBkey() ) ||
2566                          ( !$oldid ) ||
2567                      ( '' == $nt->getDBkey() ) ) {
2568                         $errors[] = array('badarticleerror');
2569                 }
2570
2571                 // Image-specific checks
2572                 if( $this->getNamespace() == NS_FILE ) {
2573                         $file = wfLocalFile( $this );
2574                         if( $file->exists() ) {
2575                                 if( $nt->getNamespace() != NS_FILE ) {
2576                                         $errors[] = array('imagenocrossnamespace');
2577                                 }
2578                                 if( $nt->getText() != wfStripIllegalFilenameChars( $nt->getText() ) ) {
2579                                         $errors[] = array('imageinvalidfilename');
2580                                 }
2581                                 if( !File::checkExtensionCompatibility( $file, $nt->getDBKey() ) ) {
2582                                         $errors[] = array('imagetypemismatch');
2583                                 }
2584                         }
2585                 }
2586
2587                 if ( $auth ) {
2588                         $errors = wfMergeErrorArrays( $errors,
2589                                 $this->getUserPermissionsErrors('move', $wgUser),
2590                                 $this->getUserPermissionsErrors('edit', $wgUser),
2591                                 $nt->getUserPermissionsErrors('move-target', $wgUser),
2592                                 $nt->getUserPermissionsErrors('edit', $wgUser) );
2593                 }
2594
2595                 $match = EditPage::matchSpamRegex( $reason );
2596                 if( $match !== false ) {
2597                         // This is kind of lame, won't display nice
2598                         $errors[] = array('spamprotectiontext');
2599                 }
2600
2601                 $err = null;
2602                 if( !wfRunHooks( 'AbortMove', array( $this, $nt, $wgUser, &$err, $reason ) ) ) {
2603                         $errors[] = array('hookaborted', $err);
2604                 }
2605
2606                 # The move is allowed only if (1) the target doesn't exist, or
2607                 # (2) the target is a redirect to the source, and has no history
2608                 # (so we can undo bad moves right after they're done).
2609
2610                 if ( 0 != $newid ) { # Target exists; check for validity
2611                         if ( ! $this->isValidMoveTarget( $nt ) ) {
2612                                 $errors[] = array('articleexists');
2613                         }
2614                 } else {
2615                         $tp = $nt->getTitleProtection();
2616                         $right = ( $tp['pt_create_perm'] == 'sysop' ) ? 'protect' : $tp['pt_create_perm'];
2617                         if ( $tp and !$wgUser->isAllowed( $right ) ) {
2618                                 $errors[] = array('cantmove-titleprotected');
2619                         }
2620                 }
2621                 if(empty($errors))
2622                         return true;
2623                 return $errors;
2624         }
2625
2626         /**
2627          * Move a title to a new location
2628          * @param &$nt \type{Title} the new title
2629          * @param $auth \type{\bool} indicates whether $wgUser's permissions
2630          *      should be checked
2631          * @param $reason \type{\string} The reason for the move
2632          * @param $createRedirect \type{\bool} Whether to create a redirect from the old title to the new title.
2633          *  Ignored if the user doesn't have the suppressredirect right.
2634          * @return \type{\mixed} true on success, getUserPermissionsErrors()-like array on failure
2635          */
2636         public function moveTo( &$nt, $auth = true, $reason = '', $createRedirect = true ) {
2637                 $err = $this->isValidMoveOperation( $nt, $auth, $reason );
2638                 if( is_array( $err ) ) {
2639                         return $err;
2640                 }
2641
2642                 $pageid = $this->getArticleID();
2643                 $protected = $this->isProtected();
2644                 if( $nt->exists() ) {
2645                         $err = $this->moveOverExistingRedirect( $nt, $reason, $createRedirect );
2646                         $pageCountChange = ($createRedirect ? 0 : -1);
2647                 } else { # Target didn't exist, do normal move.
2648                         $err = $this->moveToNewTitle( $nt, $reason, $createRedirect );
2649                         $pageCountChange = ($createRedirect ? 1 : 0);
2650                 }
2651
2652                 if( is_array( $err ) ) {
2653                         return $err;
2654                 }
2655                 $redirid = $this->getArticleID();
2656
2657                 // Category memberships include a sort key which may be customized.
2658                 // If it's left as the default (the page title), we need to update
2659                 // the sort key to match the new title.
2660                 //
2661                 // Be careful to avoid resetting cl_timestamp, which may disturb
2662                 // time-based lists on some sites.
2663                 //
2664                 // Warning -- if the sort key is *explicitly* set to the old title,
2665                 // we can't actually distinguish it from a default here, and it'll
2666                 // be set to the new title even though it really shouldn't.
2667                 // It'll get corrected on the next edit, but resetting cl_timestamp.
2668                 $dbw = wfGetDB( DB_MASTER );
2669                 $dbw->update( 'categorylinks',
2670                         array(
2671                                 'cl_sortkey' => $nt->getPrefixedText(),
2672                                 'cl_timestamp=cl_timestamp' ),
2673                         array(
2674                                 'cl_from' => $pageid,
2675                                 'cl_sortkey' => $this->getPrefixedText() ),
2676                         __METHOD__ );
2677
2678                 if( $protected ) {
2679                         # Protect the redirect title as the title used to be...
2680                         $dbw->insertSelect( 'page_restrictions', 'page_restrictions',
2681                                 array(
2682                                         'pr_page'    => $redirid,
2683                                         'pr_type'    => 'pr_type',
2684                                         'pr_level'   => 'pr_level',
2685                                         'pr_cascade' => 'pr_cascade',
2686                                         'pr_user'    => 'pr_user',
2687                                         'pr_expiry'  => 'pr_expiry'
2688                                 ),
2689                                 array( 'pr_page' => $pageid ),
2690                                 __METHOD__,
2691                                 array( 'IGNORE' )
2692                         );
2693                         # Update the protection log
2694                         $log = new LogPage( 'protect' );
2695                         $comment = wfMsgForContent( 'prot_1movedto2', $this->getPrefixedText(), $nt->getPrefixedText() );
2696                         if( $reason ) $comment .= wfMsgForContent( 'colon-separator' ) . $reason;
2697                         $log->addEntry( 'move_prot', $nt, $comment, array($this->getPrefixedText()) ); // FIXME: $params?
2698                 }
2699
2700                 # Update watchlists
2701                 $oldnamespace = $this->getNamespace() & ~1;
2702                 $newnamespace = $nt->getNamespace() & ~1;
2703                 $oldtitle = $this->getDBkey();
2704                 $newtitle = $nt->getDBkey();
2705
2706                 if( $oldnamespace != $newnamespace || $oldtitle != $newtitle ) {
2707                         WatchedItem::duplicateEntries( $this, $nt );
2708                 }
2709
2710                 # Update search engine
2711                 $u = new SearchUpdate( $pageid, $nt->getPrefixedDBkey() );
2712                 $u->doUpdate();
2713                 $u = new SearchUpdate( $redirid, $this->getPrefixedDBkey(), '' );
2714                 $u->doUpdate();
2715
2716                 # Update site_stats
2717                 if( $this->isContentPage() && !$nt->isContentPage() ) {
2718                         # No longer a content page
2719                         # Not viewed, edited, removing
2720                         $u = new SiteStatsUpdate( 0, 1, -1, $pageCountChange );
2721                 } elseif( !$this->isContentPage() && $nt->isContentPage() ) {
2722                         # Now a content page
2723                         # Not viewed, edited, adding
2724                         $u = new SiteStatsUpdate( 0, 1, +1, $pageCountChange );
2725                 } elseif( $pageCountChange ) {
2726                         # Redirect added
2727                         $u = new SiteStatsUpdate( 0, 0, 0, 1 );
2728                 } else {
2729                         # Nothing special
2730                         $u = false;
2731                 }
2732                 if( $u )
2733                         $u->doUpdate();
2734                 # Update message cache for interface messages
2735                 if( $nt->getNamespace() == NS_MEDIAWIKI ) {
2736                         global $wgMessageCache;
2737                         $oldarticle = new Article( $this );
2738                         $wgMessageCache->replace( $this->getDBkey(), $oldarticle->getContent() );
2739                         $newarticle = new Article( $nt );
2740                         $wgMessageCache->replace( $nt->getDBkey(), $newarticle->getContent() );
2741                 }
2742
2743                 global $wgUser;
2744                 wfRunHooks( 'TitleMoveComplete', array( &$this, &$nt, &$wgUser, $pageid, $redirid ) );
2745                 return true;
2746         }
2747
2748         /**
2749          * Move page to a title which is at present a redirect to the
2750          * source page
2751          *
2752          * @param &$nt \type{Title} the page to move to, which should currently
2753          *      be a redirect
2754          * @param $reason \type{\string} The reason for the move
2755          * @param $createRedirect \type{\bool} Whether to leave a redirect at the old title.
2756          *  Ignored if the user doesn't have the suppressredirect right
2757          */
2758         private function moveOverExistingRedirect( &$nt, $reason = '', $createRedirect = true ) {
2759                 global $wgUseSquid, $wgUser;
2760                 $fname = 'Title::moveOverExistingRedirect';
2761                 $comment = wfMsgForContent( '1movedto2_redir', $this->getPrefixedText(), $nt->getPrefixedText() );
2762
2763                 if ( $reason ) {
2764                         $comment .= ": $reason";
2765                 }
2766
2767                 $now = wfTimestampNow();
2768                 $newid = $nt->getArticleID();
2769                 $oldid = $this->getArticleID();
2770                 $latest = $this->getLatestRevID();
2771
2772                 $dbw = wfGetDB( DB_MASTER );
2773
2774                 # Delete the old redirect. We don't save it to history since
2775                 # by definition if we've got here it's rather uninteresting.
2776                 # We have to remove it so that the next step doesn't trigger
2777                 # a conflict on the unique namespace+title index...
2778                 $dbw->delete( 'page', array( 'page_id' => $newid ), $fname );
2779                 if ( !$dbw->cascadingDeletes() ) {
2780                         $dbw->delete( 'revision', array( 'rev_page' => $newid ), __METHOD__ );
2781                         global $wgUseTrackbacks;
2782                         if ($wgUseTrackbacks)
2783                                 $dbw->delete( 'trackbacks', array( 'tb_page' => $newid ), __METHOD__ );
2784                         $dbw->delete( 'pagelinks', array( 'pl_from' => $newid ), __METHOD__ );
2785                         $dbw->delete( 'imagelinks', array( 'il_from' => $newid ), __METHOD__ );
2786                         $dbw->delete( 'categorylinks', array( 'cl_from' => $newid ), __METHOD__ );
2787                         $dbw->delete( 'templatelinks', array( 'tl_from' => $newid ), __METHOD__ );
2788                         $dbw->delete( 'externallinks', array( 'el_from' => $newid ), __METHOD__ );
2789                         $dbw->delete( 'langlinks', array( 'll_from' => $newid ), __METHOD__ );
2790                         $dbw->delete( 'redirect', array( 'rd_from' => $newid ), __METHOD__ );
2791                 }
2792
2793                 # Save a null revision in the page's history notifying of the move
2794                 $nullRevision = Revision::newNullRevision( $dbw, $oldid, $comment, true );
2795                 $nullRevId = $nullRevision->insertOn( $dbw );
2796
2797                 $article = new Article( $this );
2798                 wfRunHooks( 'NewRevisionFromEditComplete', array($article, $nullRevision, $latest, $wgUser) );
2799
2800                 # Change the name of the target page:
2801                 $dbw->update( 'page',
2802                         /* SET */ array(
2803                                 'page_touched'   => $dbw->timestamp($now),
2804                                 'page_namespace' => $nt->getNamespace(),
2805                                 'page_title'     => $nt->getDBkey(),
2806                                 'page_latest'    => $nullRevId,
2807                         ),
2808                         /* WHERE */ array( 'page_id' => $oldid ),
2809                         $fname
2810                 );
2811                 $nt->resetArticleID( $oldid );
2812
2813                 # Recreate the redirect, this time in the other direction.
2814                 if( $createRedirect || !$wgUser->isAllowed('suppressredirect') ) {
2815                         $mwRedir = MagicWord::get( 'redirect' );
2816                         $redirectText = $mwRedir->getSynonym( 0 ) . ' [[' . $nt->getPrefixedText() . "]]\n";
2817                         $redirectArticle = new Article( $this );
2818                         $newid = $redirectArticle->insertOn( $dbw );
2819                         $redirectRevision = new Revision( array(
2820                                 'page'    => $newid,
2821                                 'comment' => $comment,
2822                                 'text'    => $redirectText ) );
2823                         $redirectRevision->insertOn( $dbw );
2824                         $redirectArticle->updateRevisionOn( $dbw, $redirectRevision, 0 );
2825
2826                         wfRunHooks( 'NewRevisionFromEditComplete', array($redirectArticle, $redirectRevision, false, $wgUser) );
2827
2828                         # Now, we record the link from the redirect to the new title.
2829                         # It should have no other outgoing links...
2830                         $dbw->delete( 'pagelinks', array( 'pl_from' => $newid ), $fname );
2831                         $dbw->insert( 'pagelinks',
2832                                 array(
2833                                         'pl_from'      => $newid,
2834                                         'pl_namespace' => $nt->getNamespace(),
2835                                         'pl_title'     => $nt->getDBkey() ),
2836                                 $fname );
2837                         $redirectSuppressed = false;
2838                 } else {
2839                         $this->resetArticleID( 0 );
2840                         $redirectSuppressed = true;
2841                 }
2842
2843                 # Move an image if this is a file
2844                 if( $this->getNamespace() == NS_FILE ) {
2845                         $file = wfLocalFile( $this );
2846                         if( $file->exists() ) {
2847                                 $status = $file->move( $nt );
2848                                 if( !$status->isOk() ) {
2849                                         $dbw->rollback();
2850                                         return $status->getErrorsArray();
2851                                 }
2852                         }
2853                 }
2854
2855                 # Log the move
2856                 $log = new LogPage( 'move' );
2857                 $log->addEntry( 'move_redir', $this, $reason, array( 1 => $nt->getPrefixedText(), 2 => $redirectSuppressed ) );
2858
2859                 # Purge squid
2860                 if ( $wgUseSquid ) {
2861                         $urls = array_merge( $nt->getSquidURLs(), $this->getSquidURLs() );
2862                         $u = new SquidUpdate( $urls );
2863                         $u->doUpdate();
2864                 }
2865
2866         }
2867
2868         /**
2869          * Move page to non-existing title.
2870          * @param &$nt \type{Title} the new Title
2871          * @param $reason \type{\string} The reason for the move
2872          * @param $createRedirect \type{\bool} Whether to create a redirect from the old title to the new title
2873          *  Ignored if the user doesn't have the suppressredirect right
2874          */
2875         private function moveToNewTitle( &$nt, $reason = '', $createRedirect = true ) {
2876                 global $wgUseSquid, $wgUser;
2877                 $fname = 'MovePageForm::moveToNewTitle';
2878                 $comment = wfMsgForContent( '1movedto2', $this->getPrefixedText(), $nt->getPrefixedText() );
2879                 if ( $reason ) {
2880                         $comment .= wfMsgExt( 'colon-separator',
2881                                 array( 'escapenoentities', 'content' ) );
2882                         $comment .= $reason;
2883                 }
2884
2885                 $newid = $nt->getArticleID();
2886                 $oldid = $this->getArticleID();
2887                 $latest = $this->getLatestRevId();
2888
2889                 $dbw = wfGetDB( DB_MASTER );
2890                 $now = $dbw->timestamp();
2891
2892                 # Save a null revision in the page's history notifying of the move
2893                 $nullRevision = Revision::newNullRevision( $dbw, $oldid, $comment, true );
2894                 $nullRevId = $nullRevision->insertOn( $dbw );
2895
2896                 $article = new Article( $this );
2897                 wfRunHooks( 'NewRevisionFromEditComplete', array($article, $nullRevision, $latest, $wgUser) );
2898
2899                 # Rename page entry
2900                 $dbw->update( 'page',
2901                         /* SET */ array(
2902                                 'page_touched'   => $now,
2903                                 'page_namespace' => $nt->getNamespace(),
2904                                 'page_title'     => $nt->getDBkey(),
2905                                 'page_latest'    => $nullRevId,
2906                         ),
2907                         /* WHERE */ array( 'page_id' => $oldid ),
2908                         $fname
2909                 );
2910                 $nt->resetArticleID( $oldid );
2911
2912                 if( $createRedirect || !$wgUser->isAllowed('suppressredirect') ) {
2913                         # Insert redirect
2914                         $mwRedir = MagicWord::get( 'redirect' );
2915                         $redirectText = $mwRedir->getSynonym( 0 ) . ' [[' . $nt->getPrefixedText() . "]]\n";
2916                         $redirectArticle = new Article( $this );
2917                         $newid = $redirectArticle->insertOn( $dbw );
2918                         $redirectRevision = new Revision( array(
2919                                 'page'    => $newid,
2920                                 'comment' => $comment,
2921                                 'text'    => $redirectText ) );
2922                         $redirectRevision->insertOn( $dbw );
2923                         $redirectArticle->updateRevisionOn( $dbw, $redirectRevision, 0 );
2924
2925                         wfRunHooks( 'NewRevisionFromEditComplete', array($redirectArticle, $redirectRevision, false, $wgUser) );
2926
2927                         # Record the just-created redirect's linking to the page
2928                         $dbw->insert( 'pagelinks',
2929                                 array(
2930                                         'pl_from'      => $newid,
2931                                         'pl_namespace' => $nt->getNamespace(),
2932                                         'pl_title'     => $nt->getDBkey() ),
2933                                 $fname );
2934                         $redirectSuppressed = false;
2935                 } else {
2936                         $this->resetArticleID( 0 );
2937                         $redirectSuppressed = true;
2938                 }
2939
2940                 # Move an image if this is a file
2941                 if( $this->getNamespace() == NS_FILE ) {
2942                         $file = wfLocalFile( $this );
2943                         if( $file->exists() ) {
2944                                 $status = $file->move( $nt );
2945                                 if( !$status->isOk() ) {
2946                                         $dbw->rollback();
2947                                         return $status->getErrorsArray();
2948                                 }
2949                         }
2950                 }
2951
2952                 # Log the move
2953                 $log = new LogPage( 'move' );
2954                 $log->addEntry( 'move', $this, $reason, array( 1 => $nt->getPrefixedText(), 2 => $redirectSuppressed ) );
2955
2956                 # Purge caches as per article creation
2957                 Article::onArticleCreate( $nt );
2958
2959                 # Purge old title from squid
2960                 # The new title, and links to the new title, are purged in Article::onArticleCreate()
2961                 $this->purgeSquid();
2962
2963         }
2964
2965         /**
2966          * Move this page's subpages to be subpages of $nt
2967          * @param $nt Title Move target
2968          * @param $auth bool Whether $wgUser's permissions should be checked
2969          * @param $reason string The reason for the move
2970          * @param $createRedirect bool Whether to create redirects from the old subpages to the new ones
2971          *  Ignored if the user doesn't have the 'suppressredirect' right
2972          * @return mixed array with old page titles as keys, and strings (new page titles) or
2973          *  arrays (errors) as values, or an error array with numeric indices if no pages were moved
2974          */
2975         public function moveSubpages( $nt, $auth = true, $reason = '', $createRedirect = true ) {
2976                 global $wgUser, $wgMaximumMovedPages;
2977                 // Check permissions
2978                 if( !$this->userCan( 'move-subpages' ) )
2979                         return array( 'cant-move-subpages' );
2980                 // Do the source and target namespaces support subpages?
2981                 if( !MWNamespace::hasSubpages( $this->getNamespace() ) )
2982                         return array( 'namespace-nosubpages',
2983                                 MWNamespace::getCanonicalName( $this->getNamespace() ) );
2984                 if( !MWNamespace::hasSubpages( $nt->getNamespace() ) )
2985                         return array( 'namespace-nosubpages',
2986                                 MWNamespace::getCanonicalName( $nt->getNamespace() ) );
2987
2988                 $subpages = $this->getSubpages($wgMaximumMovedPages + 1);
2989                 $retval = array();
2990                 $count = 0;
2991                 foreach( $subpages as $oldSubpage ) {
2992                         $count++;
2993                         if( $count > $wgMaximumMovedPages ) {
2994                                 $retval[$oldSubpage->getPrefixedTitle()] =
2995                                                 array( 'movepage-max-pages',
2996                                                         $wgMaximumMovedPages );
2997                                 break;
2998                         }
2999
3000                         if( $oldSubpage->getArticleId() == $this->getArticleId() )
3001                                 // When moving a page to a subpage of itself,
3002                                 // don't move it twice
3003                                 continue;
3004                         $newPageName = preg_replace(
3005                                         '#^'.preg_quote( $this->getDBKey(), '#' ).'#',
3006                                         $nt->getDBKey(), $oldSubpage->getDBKey() );
3007                         if( $oldSubpage->isTalkPage() ) {
3008                                 $newNs = $nt->getTalkPage()->getNamespace();
3009                         } else {
3010                                 $newNs = $nt->getSubjectPage()->getNamespace();
3011                         }
3012                         # Bug 14385: we need makeTitleSafe because the new page names may
3013                         # be longer than 255 characters.
3014                         $newSubpage = Title::makeTitleSafe( $newNs, $newPageName );
3015
3016                         $success = $oldSubpage->moveTo( $newSubpage, $auth, $reason, $createRedirect );
3017                         if( $success === true ) {
3018                                 $retval[$oldSubpage->getPrefixedText()] = $newSubpage->getPrefixedText();
3019                         } else {
3020                                 $retval[$oldSubpage->getPrefixedText()] = $success;
3021                         }
3022                 }
3023                 return $retval;
3024         }
3025
3026         /**
3027          * Checks if this page is just a one-rev redirect.
3028          * Adds lock, so don't use just for light purposes.
3029          *
3030          * @return \type{\bool} TRUE or FALSE
3031          */
3032         public function isSingleRevRedirect() {
3033                 $dbw = wfGetDB( DB_MASTER );
3034                 # Is it a redirect?
3035                 $row = $dbw->selectRow( 'page',
3036                         array( 'page_is_redirect', 'page_latest', 'page_id' ),
3037                         $this->pageCond(),
3038                         __METHOD__,
3039                         array( 'FOR UPDATE' )
3040                 );
3041                 # Cache some fields we may want
3042                 $this->mArticleID = $row ? intval($row->page_id) : 0;
3043                 $this->mRedirect = $row ? (bool)$row->page_is_redirect : false;
3044                 $this->mLatestID = $row ? intval($row->page_latest) : false;
3045                 if( !$this->mRedirect ) {
3046                         return false;
3047                 }
3048                 # Does the article have a history?
3049                 $row = $dbw->selectField( array( 'page', 'revision'),
3050                         'rev_id',
3051                         array( 'page_namespace' => $this->getNamespace(),
3052                                 'page_title' => $this->getDBkey(),
3053                                 'page_id=rev_page',
3054                                 'page_latest != rev_id'
3055                         ),
3056                         __METHOD__,
3057                         array( 'FOR UPDATE' )
3058                 );
3059                 # Return true if there was no history
3060                 return ($row === false);
3061         }
3062
3063         /**
3064          * Checks if $this can be moved to a given Title
3065          * - Selects for update, so don't call it unless you mean business
3066          *
3067          * @param &$nt \type{Title} the new title to check
3068          * @return \type{\bool} TRUE or FALSE
3069          */
3070         public function isValidMoveTarget( $nt ) {
3071                 $dbw = wfGetDB( DB_MASTER );
3072                 # Is it an existsing file?
3073                 if( $nt->getNamespace() == NS_FILE ) {
3074                         $file = wfLocalFile( $nt );
3075                         if( $file->exists() ) {
3076                                 wfDebug( __METHOD__ . ": file exists\n" );
3077                                 return false;
3078                         }
3079                 }
3080                 # Is it a redirect with no history?
3081                 if( !$nt->isSingleRevRedirect() ) {
3082                         wfDebug( __METHOD__ . ": not a one-rev redirect\n" );
3083                         return false;
3084                 }
3085                 # Get the article text
3086                 $rev = Revision::newFromTitle( $nt );
3087                 $text = $rev->getText();
3088                 # Does the redirect point to the source?
3089                 # Or is it a broken self-redirect, usually caused by namespace collisions?
3090                 $m = array();
3091                 if ( preg_match( "/\\[\\[\\s*([^\\]\\|]*)]]/", $text, $m ) ) {
3092                         $redirTitle = Title::newFromText( $m[1] );
3093                         if( !is_object( $redirTitle ) ||
3094                                 ( $redirTitle->getPrefixedDBkey() != $this->getPrefixedDBkey() &&
3095                                 $redirTitle->getPrefixedDBkey() != $nt->getPrefixedDBkey() ) ) {
3096                                 wfDebug( __METHOD__ . ": redirect points to other page\n" );
3097                                 return false;
3098                         }
3099                 } else {
3100                         # Fail safe
3101                         wfDebug( __METHOD__ . ": failsafe\n" );
3102                         return false;
3103                 }
3104                 return true;
3105         }
3106
3107         /**
3108          * Can this title be added to a user's watchlist?
3109          *
3110          * @return \type{\bool} TRUE or FALSE
3111          */
3112         public function isWatchable() {
3113                 return !$this->isExternal() && MWNamespace::isWatchable( $this->getNamespace() );
3114         }
3115
3116         /**
3117          * Get categories to which this Title belongs and return an array of
3118          * categories' names.
3119          *
3120          * @return \type{\array} array an array of parents in the form:
3121          *      $parent => $currentarticle
3122          */
3123         public function getParentCategories() {
3124                 global $wgContLang;
3125
3126                 $titlekey = $this->getArticleId();
3127                 $dbr = wfGetDB( DB_SLAVE );
3128                 $categorylinks = $dbr->tableName( 'categorylinks' );
3129
3130                 # NEW SQL
3131                 $sql = "SELECT * FROM $categorylinks"
3132                      ." WHERE cl_from='$titlekey'"
3133                          ." AND cl_from <> '0'"
3134                          ." ORDER BY cl_sortkey";
3135
3136                 $res = $dbr->query( $sql );
3137
3138                 if( $dbr->numRows( $res ) > 0 ) {
3139                         foreach( $res as $row )
3140                                 //$data[] = Title::newFromText($wgContLang->getNSText ( NS_CATEGORY ).':'.$row->cl_to);
3141                                 $data[$wgContLang->getNSText( NS_CATEGORY ).':'.$row->cl_to] = $this->getFullText();
3142                         $dbr->freeResult( $res );
3143                 } else {
3144                         $data = array();
3145                 }
3146                 return $data;
3147         }
3148
3149         /**
3150          * Get a tree of parent categories
3151          * @param $children \type{\array} an array with the children in the keys, to check for circular refs
3152          * @return \type{\array} Tree of parent categories
3153          */
3154         public function getParentCategoryTree( $children = array() ) {
3155                 $stack = array();
3156                 $parents = $this->getParentCategories();
3157
3158                 if( $parents ) {
3159                         foreach( $parents as $parent => $current ) {
3160                                 if ( array_key_exists( $parent, $children ) ) {
3161                                         # Circular reference
3162                                         $stack[$parent] = array();
3163                                 } else {
3164                                         $nt = Title::newFromText($parent);
3165                                         if ( $nt ) {
3166                                                 $stack[$parent] = $nt->getParentCategoryTree( $children + array($parent => 1) );
3167                                         }
3168                                 }
3169                         }
3170                         return $stack;
3171                 } else {
3172                         return array();
3173                 }
3174         }
3175
3176
3177         /**
3178          * Get an associative array for selecting this title from
3179          * the "page" table
3180          *
3181          * @return \type{\array} Selection array
3182          */
3183         public function pageCond() {
3184                 if( $this->mArticleID > 0 ) {
3185                         // PK avoids secondary lookups in InnoDB, shouldn't hurt other DBs
3186                         return array( 'page_id' => $this->mArticleID );
3187                 } else {
3188                         return array( 'page_namespace' => $this->mNamespace, 'page_title' => $this->mDbkeyform );
3189                 }
3190         }
3191
3192         /**
3193          * Get the revision ID of the previous revision
3194          *
3195          * @param $revId \type{\int} Revision ID. Get the revision that was before this one.
3196          * @param $flags \type{\int} GAID_FOR_UPDATE
3197          * @return \twotypes{\int,\bool} Old revision ID, or FALSE if none exists
3198          */
3199         public function getPreviousRevisionID( $revId, $flags=0 ) {
3200                 $db = ($flags & GAID_FOR_UPDATE) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
3201                 return $db->selectField( 'revision', 'rev_id',
3202                         array(
3203                                 'rev_page' => $this->getArticleId($flags),
3204                                 'rev_id < ' . intval( $revId )
3205                         ),
3206                         __METHOD__,
3207                         array( 'ORDER BY' => 'rev_id DESC' )
3208                 );
3209         }
3210
3211         /**
3212          * Get the revision ID of the next revision
3213          *
3214          * @param $revId \type{\int} Revision ID. Get the revision that was after this one.
3215          * @param $flags \type{\int} GAID_FOR_UPDATE
3216          * @return \twotypes{\int,\bool} Next revision ID, or FALSE if none exists
3217          */
3218         public function getNextRevisionID( $revId, $flags=0 ) {
3219                 $db = ($flags & GAID_FOR_UPDATE) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
3220                 return $db->selectField( 'revision', 'rev_id',
3221                         array(
3222                                 'rev_page' => $this->getArticleId($flags),
3223                                 'rev_id > ' . intval( $revId )
3224                         ),
3225                         __METHOD__,
3226                         array( 'ORDER BY' => 'rev_id' )
3227                 );
3228         }
3229
3230         /**
3231          * Get the first revision of the page
3232          *
3233          * @param $flags \type{\int} GAID_FOR_UPDATE
3234          * @return Revision (or NULL if page doesn't exist)
3235          */
3236         public function getFirstRevision( $flags=0 ) {
3237                 $db = ($flags & GAID_FOR_UPDATE) ? wfGetDB( DB_MASTER ) : wfGetDB( DB_SLAVE );
3238                 $pageId = $this->getArticleId($flags);
3239                 if( !$pageId ) return NULL;
3240                 $row = $db->selectRow( 'revision', '*',
3241                         array( 'rev_page' => $pageId ),
3242                         __METHOD__,
3243                         array( 'ORDER BY' => 'rev_timestamp ASC', 'LIMIT' => 1 )
3244                 );
3245                 if( !$row ) {
3246                         return NULL;
3247                 } else {
3248                         return new Revision( $row );
3249                 }
3250         }
3251
3252         /**
3253          * Check if this is a new page
3254          *
3255          * @return bool
3256          */
3257         public function isNewPage() {
3258                 $dbr = wfGetDB( DB_SLAVE );
3259                 return (bool)$dbr->selectField( 'page', 'page_is_new', $this->pageCond(), __METHOD__ );
3260         }
3261
3262         /**
3263          * Get the oldest revision timestamp of this page
3264          *
3265          * @return string, MW timestamp
3266          */
3267         public function getEarliestRevTime() {
3268                 $dbr = wfGetDB( DB_SLAVE );
3269                 if( $this->exists() ) {
3270                         $min = $dbr->selectField( 'revision',
3271                                 'MIN(rev_timestamp)',
3272                                 array( 'rev_page' => $this->getArticleId() ),
3273                                 __METHOD__ );
3274                         return wfTimestampOrNull( TS_MW, $min );
3275                 }
3276                 return null;
3277         }
3278
3279         /**
3280          * Get the number of revisions between the given revision IDs.
3281          * Used for diffs and other things that really need it.
3282          *
3283          * @param $old \type{\int} Revision ID.
3284          * @param $new \type{\int} Revision ID.
3285          * @return \type{\int} Number of revisions between these IDs.
3286          */
3287         public function countRevisionsBetween( $old, $new ) {
3288                 $dbr = wfGetDB( DB_SLAVE );
3289                 return $dbr->selectField( 'revision', 'count(*)',
3290                         'rev_page = ' . intval( $this->getArticleId() ) .
3291                         ' AND rev_id > ' . intval( $old ) .
3292                         ' AND rev_id < ' . intval( $new ),
3293                         __METHOD__,
3294                         array( 'USE INDEX' => 'PRIMARY' ) );
3295         }
3296
3297         /**
3298          * Compare with another title.
3299          *
3300          * @param \type{Title} $title
3301          * @return \type{\bool} TRUE or FALSE
3302          */
3303         public function equals( Title $title ) {
3304                 // Note: === is necessary for proper matching of number-like titles.
3305                 return $this->getInterwiki() === $title->getInterwiki()
3306                         && $this->getNamespace() == $title->getNamespace()
3307                         && $this->getDBkey() === $title->getDBkey();
3308         }
3309
3310         /**
3311          * Callback for usort() to do title sorts by (namespace, title)
3312          */
3313         static function compare( $a, $b ) {
3314                 if( $a->getNamespace() == $b->getNamespace() ) {
3315                         return strcmp( $a->getText(), $b->getText() );
3316                 } else {
3317                         return $a->getNamespace() - $b->getNamespace();
3318                 }
3319         }
3320
3321         /**
3322          * Return a string representation of this title
3323          *
3324          * @return \type{\string} String representation of this title
3325          */
3326         public function __toString() {
3327                 return $this->getPrefixedText();
3328         }
3329
3330         /**
3331          * Check if page exists.  For historical reasons, this function simply
3332          * checks for the existence of the title in the page table, and will
3333          * thus return false for interwiki links, special pages and the like.
3334          * If you want to know if a title can be meaningfully viewed, you should
3335          * probably call the isKnown() method instead.
3336          *
3337          * @return \type{\bool} TRUE or FALSE
3338          */
3339         public function exists() {
3340                 return $this->getArticleId() != 0;
3341         }
3342
3343         /**
3344          * Should links to this title be shown as potentially viewable (i.e. as
3345          * "bluelinks"), even if there's no record by this title in the page
3346          * table?
3347          *
3348          * This function is semi-deprecated for public use, as well as somewhat
3349          * misleadingly named.  You probably just want to call isKnown(), which
3350          * calls this function internally.
3351          *
3352          * (ISSUE: Most of these checks are cheap, but the file existence check
3353          * can potentially be quite expensive.  Including it here fixes a lot of
3354          * existing code, but we might want to add an optional parameter to skip
3355          * it and any other expensive checks.)
3356          *
3357          * @return \type{\bool} TRUE or FALSE
3358          */
3359         public function isAlwaysKnown() {
3360                 if( $this->mInterwiki != '' ) {
3361                         return true;  // any interwiki link might be viewable, for all we know
3362                 }
3363                 switch( $this->mNamespace ) {
3364                 case NS_MEDIA:
3365                 case NS_FILE:
3366                         return wfFindFile( $this );  // file exists, possibly in a foreign repo
3367                 case NS_SPECIAL:
3368                         return SpecialPage::exists( $this->getDBKey() );  // valid special page
3369                 case NS_MAIN:
3370                         return $this->mDbkeyform == '';  // selflink, possibly with fragment
3371                 case NS_MEDIAWIKI:
3372                         // If the page is form Mediawiki:message/lang, calling wfMsgWeirdKey causes
3373                         // the full l10n of that language to be loaded. That takes much memory and
3374                         // isn't needed. So we strip the language part away.
3375                         // Also, extension messages which are not loaded, are shown as red, because
3376                         // we don't call MessageCache::loadAllMessages.
3377                         list( $basename, /* rest */ ) = explode( '/', $this->mDbkeyform, 2 );
3378                         return wfMsgWeirdKey( $basename );  // known system message
3379                 default:
3380                         return false;
3381                 }
3382         }
3383
3384         /**
3385          * Does this title refer to a page that can (or might) be meaningfully
3386          * viewed?  In particular, this function may be used to determine if
3387          * links to the title should be rendered as "bluelinks" (as opposed to
3388          * "redlinks" to non-existent pages).
3389          *
3390          * @return \type{\bool} TRUE or FALSE
3391          */
3392         public function isKnown() {
3393                 return $this->exists() || $this->isAlwaysKnown();
3394         }
3395
3396         /**
3397         * Is this in a namespace that allows actual pages?
3398         *
3399         * @return \type{\bool} TRUE or FALSE
3400         */
3401         public function canExist() {
3402                 return $this->mNamespace >= 0 && $this->mNamespace != NS_MEDIA;
3403         }
3404
3405         /**
3406          * Update page_touched timestamps and send squid purge messages for
3407          * pages linking to this title. May be sent to the job queue depending
3408          * on the number of links. Typically called on create and delete.
3409          */
3410         public function touchLinks() {
3411                 $u = new HTMLCacheUpdate( $this, 'pagelinks' );
3412                 $u->doUpdate();
3413
3414                 if ( $this->getNamespace() == NS_CATEGORY ) {
3415                         $u = new HTMLCacheUpdate( $this, 'categorylinks' );
3416                         $u->doUpdate();
3417                 }
3418         }
3419
3420         /**
3421          * Get the last touched timestamp
3422          * @param Database $db, optional db
3423          * @return \type{\string} Last touched timestamp
3424          */
3425         public function getTouched( $db = NULL ) {
3426                 $db = isset($db) ? $db : wfGetDB( DB_SLAVE );
3427                 $touched = $db->selectField( 'page', 'page_touched', $this->pageCond(), __METHOD__ );
3428                 return $touched;
3429         }
3430
3431         /**
3432          * Get the timestamp when this page was updated since the user last saw it.
3433          * @param User $user
3434          * @return mixed string/NULL
3435          */
3436         public function getNotificationTimestamp( $user = NULL ) {
3437                 global $wgUser, $wgShowUpdatedMarker;
3438                 // Assume current user if none given
3439                 if( !$user ) $user = $wgUser;
3440                 // Check cache first
3441                 $uid = $user->getId();
3442                 if( isset($this->mNotificationTimestamp[$uid]) ) {
3443                         return $this->mNotificationTimestamp[$uid];
3444                 }
3445                 if( !$uid || !$wgShowUpdatedMarker ) {
3446                         return $this->mNotificationTimestamp[$uid] = false;
3447                 }
3448                 // Don't cache too much!
3449                 if( count($this->mNotificationTimestamp) >= self::CACHE_MAX ) {
3450                         $this->mNotificationTimestamp = array();
3451                 }
3452                 $dbr = wfGetDB( DB_SLAVE );
3453                 $this->mNotificationTimestamp[$uid] = $dbr->selectField( 'watchlist',
3454                         'wl_notificationtimestamp',
3455                         array( 'wl_namespace' => $this->getNamespace(),
3456                                 'wl_title' => $this->getDBkey(),
3457                                 'wl_user' => $user->getId()
3458                         ),
3459                         __METHOD__
3460                 );
3461                 return $this->mNotificationTimestamp[$uid];
3462         }
3463
3464         /**
3465          * Get the trackback URL for this page
3466          * @return \type{\string} Trackback URL
3467          */
3468         public function trackbackURL() {
3469                 global $wgScriptPath, $wgServer;
3470
3471                 return "$wgServer$wgScriptPath/trackback.php?article="
3472                         . htmlspecialchars(urlencode($this->getPrefixedDBkey()));
3473         }
3474
3475         /**
3476          * Get the trackback RDF for this page
3477          * @return \type{\string} Trackback RDF
3478          */
3479         public function trackbackRDF() {
3480                 $url = htmlspecialchars($this->getFullURL());
3481                 $title = htmlspecialchars($this->getText());
3482                 $tburl = $this->trackbackURL();
3483
3484                 // Autodiscovery RDF is placed in comments so HTML validator
3485                 // won't barf. This is a rather icky workaround, but seems
3486                 // frequently used by this kind of RDF thingy.
3487                 //
3488                 // Spec: http://www.sixapart.com/pronet/docs/trackback_spec
3489                 return "<!--
3490 <rdf:RDF xmlns:rdf=\"http://www.w3.org/1999/02/22-rdf-syntax-ns#\"
3491          xmlns:dc=\"http://purl.org/dc/elements/1.1/\"
3492          xmlns:trackback=\"http://madskills.com/public/xml/rss/module/trackback/\">
3493 <rdf:Description
3494    rdf:about=\"$url\"
3495    dc:identifier=\"$url\"
3496    dc:title=\"$title\"
3497    trackback:ping=\"$tburl\" />
3498 </rdf:RDF>
3499 -->";
3500         }
3501
3502         /**
3503          * Generate strings used for xml 'id' names in monobook tabs
3504          * @return \type{\string} XML 'id' name
3505          */
3506         public function getNamespaceKey() {
3507                 global $wgContLang;
3508                 switch ($this->getNamespace()) {
3509                         case NS_MAIN:
3510                         case NS_TALK:
3511                                 return 'nstab-main';
3512                         case NS_USER:
3513                         case NS_USER_TALK:
3514                                 return 'nstab-user';
3515                         case NS_MEDIA:
3516                                 return 'nstab-media';
3517                         case NS_SPECIAL:
3518                                 return 'nstab-special';
3519                         case NS_PROJECT:
3520                         case NS_PROJECT_TALK:
3521                                 return 'nstab-project';
3522                         case NS_FILE:
3523                         case NS_FILE_TALK:
3524                                 return 'nstab-image';
3525                         case NS_MEDIAWIKI:
3526                         case NS_MEDIAWIKI_TALK:
3527                                 return 'nstab-mediawiki';
3528                         case NS_TEMPLATE:
3529                         case NS_TEMPLATE_TALK:
3530                                 return 'nstab-template';
3531                         case NS_HELP:
3532                         case NS_HELP_TALK:
3533                                 return 'nstab-help';
3534                         case NS_CATEGORY:
3535                         case NS_CATEGORY_TALK:
3536                                 return 'nstab-category';
3537                         default:
3538                                 return 'nstab-' . $wgContLang->lc( $this->getSubjectNsText() );
3539                 }
3540         }
3541
3542         /**
3543          * Returns true if this title resolves to the named special page
3544          * @param $name \type{\string} The special page name
3545          */
3546         public function isSpecial( $name ) {
3547                 if ( $this->getNamespace() == NS_SPECIAL ) {
3548                         list( $thisName, /* $subpage */ ) = SpecialPage::resolveAliasWithSubpage( $this->getDBkey() );
3549                         if ( $name == $thisName ) {
3550                                 return true;
3551                         }
3552                 }
3553                 return false;
3554         }
3555
3556         /**
3557          * If the Title refers to a special page alias which is not the local default,
3558          * @return \type{Title} A new Title which points to the local default. Otherwise, returns $this.
3559          */
3560         public function fixSpecialName() {
3561                 if ( $this->getNamespace() == NS_SPECIAL ) {
3562                         $canonicalName = SpecialPage::resolveAlias( $this->mDbkeyform );
3563                         if ( $canonicalName ) {
3564                                 $localName = SpecialPage::getLocalNameFor( $canonicalName );
3565                                 if ( $localName != $this->mDbkeyform ) {
3566                                         return Title::makeTitle( NS_SPECIAL, $localName );
3567                                 }
3568                         }
3569                 }
3570                 return $this;
3571         }
3572
3573         /**
3574          * Is this Title in a namespace which contains content?
3575          * In other words, is this a content page, for the purposes of calculating
3576          * statistics, etc?
3577          *
3578          * @return \type{\bool} TRUE or FALSE
3579          */
3580         public function isContentPage() {
3581                 return MWNamespace::isContent( $this->getNamespace() );
3582         }
3583
3584         /**
3585          * Get all extant redirects to this Title
3586          *
3587          * @param $ns \twotypes{\int,\null} Single namespace to consider;
3588          *            NULL to consider all namespaces
3589          * @return \type{\arrayof{Title}} Redirects to this title
3590          */
3591         public function getRedirectsHere( $ns = null ) {
3592                 $redirs = array();
3593
3594                 $dbr = wfGetDB( DB_SLAVE );
3595                 $where = array(
3596                         'rd_namespace' => $this->getNamespace(),
3597                         'rd_title' => $this->getDBkey(),
3598                         'rd_from = page_id'
3599                 );
3600                 if ( !is_null($ns) ) $where['page_namespace'] = $ns;
3601
3602                 $res = $dbr->select(
3603                         array( 'redirect', 'page' ),
3604                         array( 'page_namespace', 'page_title' ),
3605                         $where,
3606                         __METHOD__
3607                 );
3608
3609
3610                 foreach( $res as $row ) {
3611                         $redirs[] = self::newFromRow( $row );
3612                 }
3613                 return $redirs;
3614         }
3615
3616         /**
3617          * Check if this Title is a valid redirect target
3618          *
3619          * @return \type{\bool} TRUE or FALSE
3620          */
3621         public function isValidRedirectTarget() {
3622                 global $wgInvalidRedirectTargets;
3623
3624                 // invalid redirect targets are stored in a global array, but explicity disallow Userlogout here
3625                 if( $this->isSpecial( 'Userlogout' ) ) {
3626                         return false;
3627                 }
3628
3629                 foreach( $wgInvalidRedirectTargets as $target ) {
3630                         if( $this->isSpecial( $target ) ) {
3631                                 return false;
3632                         }
3633                 }
3634
3635                 return true;
3636         }
3637
3638         /**
3639          * Get a backlink cache object
3640          */
3641         function getBacklinkCache() {
3642                 if ( is_null( $this->mBacklinkCache ) ) {
3643                         $this->mBacklinkCache = new BacklinkCache( $this );
3644                 }
3645                 return $this->mBacklinkCache;
3646         }
3647 }