includes/Title.php

   1 <?php
   2 /**
   3  * See title.txt
   4  *
   5  * @package MediaWiki
   6  */
   7
   8 /** */
   9 require_once( 'normal/UtfNormal.php' );
  10
  11 $wgTitleInterwikiCache = array();
  12 define ( 'GAID_FOR_UPDATE', 1 );
  13
  14 # Title::newFromTitle maintains a cache to avoid
  15 # expensive re-normalization of commonly used titles.
  16 # On a batch operation this can become a memory leak
  17 # if not bounded. After hitting this many titles,
  18 # reset the cache.
  19 define( 'MW_TITLECACHE_MAX', 1000 );
  20
  21 /**
  22  * Title class
  23  * - Represents a title, which may contain an interwiki designation or namespace
  24  * - Can fetch various kinds of data from the database, albeit inefficiently.
  25  *
  26  * @package MediaWiki
  27  */
  28 class Title {
  29         /**
  30          * All member variables should be considered private
  31          * Please use the accessor functions
  32          */
  33
  34          /**#@+
  35          * @access private
  36          */
  37
  38         var $mTextform;           # Text form (spaces not underscores) of the main part
  39         var $mUrlform;            # URL-encoded form of the main part
  40         var $mDbkeyform;          # Main part with underscores
  41         var $mNamespace;          # Namespace index, i.e. one of the NS_xxxx constants
  42         var $mInterwiki;          # Interwiki prefix (or null string)
  43         var $mFragment;           # Title fragment (i.e. the bit after the #)
  44         var $mArticleID;          # Article ID, fetched from the link cache on demand
  45         var $mLatestID;         # ID of most recent revision
  46         var $mRestrictions;       # Array of groups allowed to edit this article
  47                               # Only null or "sysop" are supported
  48         var $mRestrictionsLoaded; # Boolean for initialisation on demand
  49         var $mPrefixedText;       # Text form including namespace/interwiki, initialised on demand
  50         var $mDefaultNamespace;   # Namespace index when there is no namespace
  51                               # Zero except in {{transclusion}} tags
  52         var $mWatched;            # Is $wgUser watching this page? NULL if unfilled, accessed through userIsWatching()
  53         /**#@-*/
  54
  55
  56         /**
  57          * Constructor
  58          * @access private
  59          */
  60         /* private */ function Title() {
  61                 $this->mInterwiki = $this->mUrlform =
  62                 $this->mTextform = $this->mDbkeyform = '';
  63                 $this->mArticleID = -1;
  64                 $this->mNamespace = NS_MAIN;
  65                 $this->mRestrictionsLoaded = false;
  66                 $this->mRestrictions = array();
  67                 # Dont change the following, NS_MAIN is hardcoded in several place
  68                 # See bug #696
  69                 $this->mDefaultNamespace = NS_MAIN;
  70                 $this->mWatched = NULL;
  71                 $this->mLatestID = false;
  72         }
  73
  74         /**
  75          * Create a new Title from a prefixed DB key
  76          * @param string $key The database key, which has underscores
  77          *      instead of spaces, possibly including namespace and
  78          *      interwiki prefixes
  79          * @return Title the new object, or NULL on an error
  80          * @static
  81          * @access public
  82          */
  83         /* static */ function newFromDBkey( $key ) {
  84                 $t = new Title();
  85                 $t->mDbkeyform = $key;
  86                 if( $t->secureAndSplit() )
  87                         return $t;
  88                 else
  89                         return NULL;
  90         }
  91
  92         /**
  93          * Create a new Title from text, such as what one would
  94          * find in a link. Decodes any HTML entities in the text.
  95          *
  96          * @param string $text the link text; spaces, prefixes,
  97          *      and an initial ':' indicating the main namespace
  98          *      are accepted
  99          * @param int $defaultNamespace the namespace to use if
 100          *      none is specified by a prefix
 101          * @return Title the new object, or NULL on an error
 102          * @static
 103          * @access public
 104          */
 105         function &newFromText( $text, $defaultNamespace = NS_MAIN ) {
 106                 $fname = 'Title::newFromText';
 107                 wfProfileIn( $fname );
 108
 109                 if( is_object( $text ) ) {
 110                         wfDebugDieBacktrace( 'Title::newFromText given an object' );
 111                 }
 112
 113                 /**
 114                  * Wiki pages often contain multiple links to the same page.
 115                  * Title normalization and parsing can become expensive on
 116                  * pages with many links, so we can save a little time by
 117                  * caching them.
 118                  *
 119                  * In theory these are value objects and won't get changed...
 120                  */
 121                 static $titleCache = array();
 122                 if( $defaultNamespace == NS_MAIN && isset( $titleCache[$text] ) ) {
 123                         wfProfileOut( $fname );
 124                         return $titleCache[$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                 if( $t->secureAndSplit() ) {
 137                         if( $defaultNamespace == NS_MAIN ) {
 138                                 if( count( $titleCache ) >= MW_TITLECACHE_MAX ) {
 139                                         # Avoid memory leaks on mass operations...
 140                                         $titleCache = array();
 141                                 }
 142                                 $titleCache[$text] =& $t;
 143                         }
 144                         wfProfileOut( $fname );
 145                         return $t;
 146                 } else {
 147                         wfProfileOut( $fname );
 148                         return NULL;
 149                 }
 150         }
 151
 152         /**
 153          * Create a new Title from URL-encoded text. Ensures that
 154          * the given title's length does not exceed the maximum.
 155          * @param string $url the title, as might be taken from a URL
 156          * @return Title the new object, or NULL on an error
 157          * @static
 158          * @access public
 159          */
 160         function newFromURL( $url ) {
 161                 global $wgLang, $wgServer;
 162                 $t = new Title();
 163
 164                 # For compatibility with old buggy URLs. "+" is 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                 $s = str_replace( '+', ' ', $url );
 168
 169                 $t->mDbkeyform = str_replace( ' ', '_', $s );
 170                 if( $t->secureAndSplit() ) {
 171                         return $t;
 172                 } else {
 173                         return NULL;
 174                 }
 175         }
 176
 177         /**
 178          * Create a new Title from an article ID
 179          *
 180          * @todo This is inefficiently implemented, the page row is requested
 181          *       but not used for anything else
 182          *
 183          * @param int $id the page_id corresponding to the Title to create
 184          * @return Title the new object, or NULL on an error
 185          * @access public
 186          * @static
 187          */
 188         function newFromID( $id ) {
 189                 $fname = 'Title::newFromID';
 190                 $dbr =& wfGetDB( DB_SLAVE );
 191                 $row = $dbr->selectRow( 'page', array( 'page_namespace', 'page_title' ),
 192                         array( 'page_id' => $id ), $fname );
 193                 if ( $row !== false ) {
 194                         $title = Title::makeTitle( $row->page_namespace, $row->page_title );
 195                 } else {
 196                         $title = NULL;
 197                 }
 198                 return $title;
 199         }
 200
 201         /**
 202          * Create a new Title from a namespace index and a DB key.
 203          * It's assumed that $ns and $title are *valid*, for instance when
 204          * they came directly from the database or a special page name.
 205          * For convenience, spaces are converted to underscores so that
 206          * eg user_text fields can be used directly.
 207          *
 208          * @param int $ns the namespace of the article
 209          * @param string $title the unprefixed database key form
 210          * @return Title the new object
 211          * @static
 212          * @access public
 213          */
 214         function &makeTitle( $ns, $title ) {
 215                 $t =& new Title();
 216                 $t->mInterwiki = '';
 217                 $t->mFragment = '';
 218                 $t->mNamespace = IntVal( $ns );
 219                 $t->mDbkeyform = str_replace( ' ', '_', $title );
 220                 $t->mArticleID = ( $ns >= 0 ) ? -1 : 0;
 221                 $t->mUrlform = wfUrlencode( $t->mDbkeyform );
 222                 $t->mTextform = str_replace( '_', ' ', $title );
 223                 return $t;
 224         }
 225
 226         /**
 227          * Create a new Title frrom a namespace index and a DB key.
 228          * The parameters will be checked for validity, which is a bit slower
 229          * than makeTitle() but safer for user-provided data.
 230          *
 231          * @param int $ns the namespace of the article
 232          * @param string $title the database key form
 233          * @return Title the new object, or NULL on an error
 234          * @static
 235          * @access public
 236          */
 237         function makeTitleSafe( $ns, $title ) {
 238                 $t = new Title();
 239                 $t->mDbkeyform = Title::makeName( $ns, $title );
 240                 if( $t->secureAndSplit() ) {
 241                         return $t;
 242                 } else {
 243                         return NULL;
 244                 }
 245         }
 246
 247         /**
 248          * Create a new Title for the Main Page
 249          *
 250          * @static
 251          * @return Title the new object
 252          * @access public
 253          */
 254         function newMainPage() {
 255                 return Title::newFromText( wfMsgForContent( 'mainpage' ) );
 256         }
 257
 258         /**
 259          * Create a new Title for a redirect
 260          * @param string $text the redirect title text
 261          * @return Title the new object, or NULL if the text is not a
 262          *      valid redirect
 263          * @static
 264          * @access public
 265          */
 266         function newFromRedirect( $text ) {
 267                 global $wgMwRedir;
 268                 $rt = NULL;
 269                 if ( $wgMwRedir->matchStart( $text ) ) {
 270                         if ( preg_match( '/\[{2}(.*?)(?:\||\]{2})/', $text, $m ) ) {
 271                                 # categories are escaped using : for example one can enter:
 272                                 # #REDIRECT [[:Category:Music]]. Need to remove it.
 273                                 if ( substr($m[1],0,1) == ':') {
 274                                         # We don't want to keep the ':'
 275                                         $m[1] = substr( $m[1], 1 );
 276                                 }
 277
 278                                 $rt = Title::newFromText( $m[1] );
 279                                 # Disallow redirects to Special:Userlogout
 280                                 if ( !is_null($rt) && $rt->getNamespace() == NS_SPECIAL && preg_match( '/^Userlogout/i', $rt->getText() ) ) {
 281                                         $rt = NULL;
 282                                 }
 283                         }
 284                 }
 285                 return $rt;
 286         }
 287
 288 #----------------------------------------------------------------------------
 289 #       Static functions
 290 #----------------------------------------------------------------------------
 291
 292         /**
 293          * Get the prefixed DB key associated with an ID
 294          * @param int $id the page_id of the article
 295          * @return Title an object representing the article, or NULL
 296          *      if no such article was found
 297          * @static
 298          * @access public
 299          */
 300         function nameOf( $id ) {
 301                 $fname = 'Title::nameOf';
 302                 $dbr =& wfGetDB( DB_SLAVE );
 303
 304                 $s = $dbr->selectRow( 'page', array( 'page_namespace','page_title' ),  array( 'page_id' => $id ), $fname );
 305                 if ( $s === false ) { return NULL; }
 306
 307                 $n = Title::makeName( $s->page_namespace, $s->page_title );
 308                 return $n;
 309         }
 310
 311         /**
 312          * Get a regex character class describing the legal characters in a link
 313          * @return string the list of characters, not delimited
 314          * @static
 315          * @access public
 316          */
 317         function legalChars() {
 318                 # Missing characters:
 319                 #  * []|# Needed for link syntax
 320                 #  * % and + are corrupted by Apache when they appear in the path
 321                 #
 322                 # % seems to work though
 323                 #
 324                 # The problem with % is that URLs are double-unescaped: once by Apache's
 325                 # path conversion code, and again by PHP. So %253F, for example, becomes "?".
 326                 # Our code does not double-escape to compensate for this, indeed double escaping
 327                 # would break if the double-escaped title was passed in the query string
 328                 # rather than the path. This is a minor security issue because articles can be
 329                 # created such that they are hard to view or edit. -- TS
 330                 #
 331                 # Theoretically 0x80-0x9F of ISO 8859-1 should be disallowed, but
 332                 # this breaks interlanguage links
 333
 334                 $set = " %!\"$&'()*,\\-.\\/0-9:;=?@A-Z\\\\^_`a-z~\\x80-\\xFF";
 335                 return $set;
 336         }
 337
 338         /**
 339          * Get a string representation of a title suitable for
 340          * including in a search index
 341          *
 342          * @param int $ns a namespace index
 343          * @param string $title text-form main part
 344          * @return string a stripped-down title string ready for the
 345          *      search index
 346          */
 347         /* static */ function indexTitle( $ns, $title ) {
 348                 global $wgDBminWordLen, $wgContLang;
 349                 require_once( 'SearchEngine.php' );
 350
 351                 $lc = SearchEngine::legalSearchChars() . '&#;';
 352                 $t = $wgContLang->stripForSearch( $title );
 353                 $t = preg_replace( "/[^{$lc}]+/", ' ', $t );
 354                 $t = strtolower( $t );
 355
 356                 # Handle 's, s'
 357                 $t = preg_replace( "/([{$lc}]+)'s( |$)/", "\\1 \\1's ", $t );
 358                 $t = preg_replace( "/([{$lc}]+)s'( |$)/", "\\1s ", $t );
 359
 360                 $t = preg_replace( "/\\s+/", ' ', $t );
 361
 362                 if ( $ns == NS_IMAGE ) {
 363                         $t = preg_replace( "/ (png|gif|jpg|jpeg|ogg)$/", "", $t );
 364                 }
 365                 return trim( $t );
 366         }
 367
 368         /*
 369          * Make a prefixed DB key from a DB key and a namespace index
 370          * @param int $ns numerical representation of the namespace
 371          * @param string $title the DB key form the title
 372          * @return string the prefixed form of the title
 373          */
 374         /* static */ function makeName( $ns, $title ) {
 375                 global $wgContLang;
 376
 377                 $n = $wgContLang->getNsText( $ns );
 378                 return $n == '' ? $title : "$n:$title";
 379         }
 380
 381         /**
 382          * Returns the URL associated with an interwiki prefix
 383          * @param string $key the interwiki prefix (e.g. "MeatBall")
 384          * @return the associated URL, containing "$1", which should be
 385          *      replaced by an article title
 386          * @static (arguably)
 387          * @access public
 388          */
 389         function getInterwikiLink( $key, $transludeonly = false ) {
 390                 global $wgMemc, $wgDBname, $wgInterwikiExpiry, $wgTitleInterwikiCache;
 391                 $fname = 'Title::getInterwikiLink';
 392
 393                 wfProfileIn( $fname );
 394
 395                 $k = $wgDBname.':interwiki:'.$key;
 396                 if( array_key_exists( $k, $wgTitleInterwikiCache ) ) {
 397                         wfProfileOut( $fname );
 398                         return $wgTitleInterwikiCache[$k]->iw_url;
 399                 }
 400
 401                 $s = $wgMemc->get( $k );
 402                 # Ignore old keys with no iw_local
 403                 if( $s && isset( $s->iw_local ) && isset($s->iw_trans)) {
 404                         $wgTitleInterwikiCache[$k] = $s;
 405                         wfProfileOut( $fname );
 406                         return $s->iw_url;
 407                 }
 408
 409                 $dbr =& wfGetDB( DB_SLAVE );
 410                 $res = $dbr->select( 'interwiki',
 411                         array( 'iw_url', 'iw_local', 'iw_trans' ),
 412                         array( 'iw_prefix' => $key ), $fname );
 413                 if( !$res ) {
 414                         wfProfileOut( $fname );
 415                         return '';
 416                 }
 417
 418                 $s = $dbr->fetchObject( $res );
 419                 if( !$s ) {
 420                         # Cache non-existence: create a blank object and save it to memcached
 421                         $s = (object)false;
 422                         $s->iw_url = '';
 423                         $s->iw_local = 0;
 424                         $s->iw_trans = 0;
 425                 }
 426                 $wgMemc->set( $k, $s, $wgInterwikiExpiry );
 427                 $wgTitleInterwikiCache[$k] = $s;
 428
 429                 wfProfileOut( $fname );
 430                 return $s->iw_url;
 431         }
 432
 433         /**
 434          * Determine whether the object refers to a page within
 435          * this project.
 436          *
 437          * @return bool TRUE if this is an in-project interwiki link
 438          *      or a wikilink, FALSE otherwise
 439          * @access public
 440          */
 441         function isLocal() {
 442                 global $wgTitleInterwikiCache, $wgDBname;
 443
 444                 if ( $this->mInterwiki != '' ) {
 445                         # Make sure key is loaded into cache
 446                         $this->getInterwikiLink( $this->mInterwiki );
 447                         $k = $wgDBname.':interwiki:' . $this->mInterwiki;
 448                         return (bool)($wgTitleInterwikiCache[$k]->iw_local);
 449                 } else {
 450                         return true;
 451                 }
 452         }
 453
 454         /**
 455          * Determine whether the object refers to a page within
 456          * this project and is transcludable.
 457          *
 458          * @return bool TRUE if this is transcludable
 459          * @access public
 460          */
 461         function isTrans() {
 462                 global $wgTitleInterwikiCache, $wgDBname;
 463
 464                 if ($this->mInterwiki == '' || !$this->isLocal())
 465                         return false;
 466                 # Make sure key is loaded into cache
 467                 $this->getInterwikiLink( $this->mInterwiki );
 468                 $k = $wgDBname.':interwiki:' . $this->mInterwiki;
 469                 return (bool)($wgTitleInterwikiCache[$k]->iw_trans);
 470         }
 471
 472         /**
 473          * Update the page_touched field for an array of title objects
 474          * @todo Inefficient unless the IDs are already loaded into the
 475          *      link cache
 476          * @param array $titles an array of Title objects to be touched
 477          * @param string $timestamp the timestamp to use instead of the
 478          *      default current time
 479          * @static
 480          * @access public
 481          */
 482         function touchArray( $titles, $timestamp = '' ) {
 483                 global $wgUseFileCache;
 484
 485                 if ( count( $titles ) == 0 ) {
 486                         return;
 487                 }
 488                 $dbw =& wfGetDB( DB_MASTER );
 489                 if ( $timestamp == '' ) {
 490                         $timestamp = $dbw->timestamp();
 491                 }
 492                 $page = $dbw->tableName( 'page' );
 493                 $sql = "UPDATE $page SET page_touched='{$timestamp}' WHERE page_id IN (";
 494                 $first = true;
 495
 496                 foreach ( $titles as $title ) {
 497                         if ( $wgUseFileCache ) {
 498                                 $cm = new CacheManager($title);
 499                                 @unlink($cm->fileCacheName());
 500                         }
 501
 502                         if ( ! $first ) {
 503                                 $sql .= ',';
 504                         }
 505                         $first = false;
 506                         $sql .= $title->getArticleID();
 507                 }
 508                 $sql .= ')';
 509                 if ( ! $first ) {
 510                         $dbw->query( $sql, 'Title::touchArray' );
 511                 }
 512         }
 513
 514 #----------------------------------------------------------------------------
 515 #       Other stuff
 516 #----------------------------------------------------------------------------
 517
 518         /** Simple accessors */
 519         /**
 520          * Get the text form (spaces not underscores) of the main part
 521          * @return string
 522          * @access public
 523          */
 524         function getText() { return $this->mTextform; }
 525         /**
 526          * Get the URL-encoded form of the main part
 527          * @return string
 528          * @access public
 529          */
 530         function getPartialURL() { return $this->mUrlform; }
 531         /**
 532          * Get the main part with underscores
 533          * @return string
 534          * @access public
 535          */
 536         function getDBkey() { return $this->mDbkeyform; }
 537         /**
 538          * Get the namespace index, i.e. one of the NS_xxxx constants
 539          * @return int
 540          * @access public
 541          */
 542         function getNamespace() { return $this->mNamespace; }
 543         /**
 544          * Get the interwiki prefix (or null string)
 545          * @return string
 546          * @access public
 547          */
 548         function getInterwiki() { return $this->mInterwiki; }
 549         /**
 550          * Get the Title fragment (i.e. the bit after the #)
 551          * @return string
 552          * @access public
 553          */
 554         function getFragment() { return $this->mFragment; }
 555         /**
 556          * Get the default namespace index, for when there is no namespace
 557          * @return int
 558          * @access public
 559          */
 560         function getDefaultNamespace() { return $this->mDefaultNamespace; }
 561
 562         /**
 563          * Get title for search index
 564          * @return string a stripped-down title string ready for the
 565          *      search index
 566          */
 567         function getIndexTitle() {
 568                 return Title::indexTitle( $this->mNamespace, $this->mTextform );
 569         }
 570
 571         /**
 572          * Get the prefixed database key form
 573          * @return string the prefixed title, with underscores and
 574          *      any interwiki and namespace prefixes
 575          * @access public
 576          */
 577         function getPrefixedDBkey() {
 578                 $s = $this->prefix( $this->mDbkeyform );
 579                 $s = str_replace( ' ', '_', $s );
 580                 return $s;
 581         }
 582
 583         /**
 584          * Get the prefixed title with spaces.
 585          * This is the form usually used for display
 586          * @return string the prefixed title, with spaces
 587          * @access public
 588          */
 589         function getPrefixedText() {
 590                 global $wgContLang;
 591                 if ( empty( $this->mPrefixedText ) ) {
 592                         $s = $this->prefix( $this->mTextform );
 593                         $s = str_replace( '_', ' ', $s );
 594                         $this->mPrefixedText = $s;
 595                 }
 596                 return $this->mPrefixedText;
 597         }
 598
 599         /**
 600          * Get the prefixed title with spaces, plus any fragment
 601          * (part beginning with '#')
 602          * @return string the prefixed title, with spaces and
 603          *      the fragment, including '#'
 604          * @access public
 605          */
 606         function getFullText() {
 607                 global $wgContLang;
 608                 $text = $this->getPrefixedText();
 609                 if( '' != $this->mFragment ) {
 610                         $text .= '#' . $this->mFragment;
 611                 }
 612                 return $text;
 613         }
 614
 615         /**
 616          * Get a URL-encoded title (not an actual URL) including interwiki
 617          * @return string the URL-encoded form
 618          * @access public
 619          */
 620         function getPrefixedURL() {
 621                 $s = $this->prefix( $this->mDbkeyform );
 622                 $s = str_replace( ' ', '_', $s );
 623
 624                 $s = wfUrlencode ( $s ) ;
 625
 626                 # Cleaning up URL to make it look nice -- is this safe?
 627                 $s = str_replace( '%28', '(', $s );
 628                 $s = str_replace( '%29', ')', $s );
 629
 630                 return $s;
 631         }
 632
 633         /**
 634          * Get a real URL referring to this title, with interwiki link and
 635          * fragment
 636          *
 637          * @param string $query an optional query string, not used
 638          *      for interwiki links
 639          * @return string the URL
 640          * @access public
 641          */
 642         function getFullURL( $query = '' ) {
 643                 global $wgContLang, $wgServer, $wgScript, $wgMakeDumpLinks, $wgArticlePath;
 644
 645                 if ( '' == $this->mInterwiki ) {
 646                         return $wgServer . $this->getLocalUrl( $query );
 647                 } elseif ( $wgMakeDumpLinks && $wgContLang->getLanguageName( $this->mInterwiki ) ) {
 648                         $baseUrl = str_replace( '$1', "../../{$this->mInterwiki}/$1", $wgArticlePath );
 649                         $baseUrl = str_replace( '$1', $this->getHashedDirectory() . '/$1', $baseUrl );
 650                 } else {
 651                         $baseUrl = $this->getInterwikiLink( $this->mInterwiki );
 652                 }
 653
 654                 $namespace = $wgContLang->getNsText( $this->mNamespace );
 655                 if ( '' != $namespace ) {
 656                         # Can this actually happen? Interwikis shouldn't be parsed.
 657                         $namepace .= ':';
 658                 }
 659                 $url = str_replace( '$1', $namespace . $this->mUrlform, $baseUrl );
 660                 if( $query != '' ) {
 661                         if( false === strpos( $url, '?' ) ) {
 662                                 $url .= '?';
 663                         } else {
 664                                 $url .= '&';
 665                         }
 666                         $url .= $query;
 667                 }
 668                 if ( '' != $this->mFragment ) {
 669                         $url .= '#' . $this->mFragment;
 670                 }
 671                 return $url;
 672         }
 673
 674         /**
 675          * Get a relative directory for putting an HTML version of this article into
 676          */
 677         function getHashedDirectory() {
 678                 global $wgMakeDumpLinks, $wgInputEncoding;
 679                 $dbkey = $this->getDBkey();
 680
 681                 # Split into characters
 682                 if ( $wgInputEncoding == 'UTF-8' ) {
 683                         preg_match_all( '/./us', $dbkey, $m );
 684                 } else {
 685                         preg_match_all( '/./s', $dbkey, $m );
 686                 }
 687                 $chars = $m[0];
 688                 $length = count( $chars );
 689                 $dir = '';
 690
 691                 for ( $i = 0; $i < $wgMakeDumpLinks; $i++ ) {
 692                         if ( $i ) {
 693                                 $dir .= '/';
 694                         }
 695                         if ( $i >= $length ) {
 696                                 $dir .= '_';
 697                         } elseif ( ord( $chars[$i] ) > 32 ) {
 698                                 $dir .= strtolower( $chars[$i] );
 699                         } else {
 700                                 $dir .= sprintf( "%02X", ord( $chars[$i] ) );
 701                         }
 702                 }
 703                 return $dir;
 704         }
 705
 706         function getHashedFilename() {
 707                 $dbkey = $this->getPrefixedDBkey();
 708                 $mainPage = Title::newMainPage();
 709                 if ( $mainPage->getPrefixedDBkey() == $dbkey ) {
 710                         return 'index.html';
 711                 }
 712
 713                 $dir = $this->getHashedDirectory();
 714
 715                 # Replace illegal charcters for Windows paths with underscores
 716                 $friendlyName = strtr( $dbkey, '/\\*?"<>|~', '_________' );
 717
 718                 # Work out lower case form. We assume we're on a system with case-insensitive
 719                 # filenames, so unless the case is of a special form, we have to disambiguate
 720                 $lowerCase = $this->prefix( ucfirst( strtolower( $this->getDBkey() ) ) );
 721
 722                 # Make it mostly unique
 723                 if ( $lowerCase != $friendlyName  ) {
 724                         $friendlyName .= '_' . substr(md5( $dbkey ), 0, 4);
 725                 }
 726                 # Handle colon specially by replacing it with tilde
 727                 # Thus we reduce the number of paths with hashes appended
 728                 $friendlyName = str_replace( ':', '~', $friendlyName );
 729                 return "$dir/$friendlyName.html";
 730         }
 731
 732         /**
 733          * Get a URL with no fragment or server name.  If this page is generated
 734          * with action=render, $wgServer is prepended.
 735          * @param string $query an optional query string; if not specified,
 736          *      $wgArticlePath will be used.
 737          * @return string the URL
 738          * @access public
 739          */
 740         function getLocalURL( $query = '' ) {
 741                 global $wgLang, $wgArticlePath, $wgScript, $wgMakeDumpLinks, $wgServer, $action;
 742
 743                 if ( $this->isExternal() ) {
 744                         return $this->getFullURL();
 745                 }
 746
 747                 $dbkey = wfUrlencode( $this->getPrefixedDBkey() );
 748                 if ( $wgMakeDumpLinks ) {
 749                         $url = str_replace( '$1', wfUrlencode( $this->getHashedFilename() ), $wgArticlePath );
 750                 } elseif ( $query == '' ) {
 751                         $url = str_replace( '$1', $dbkey, $wgArticlePath );
 752                 } else {
 753                         global $wgActionPaths;
 754                         if( !empty( $wgActionPaths ) &&
 755                                 preg_match( '/^(.*&|)action=([^&]*)(&(.*)|)$/', $query, $matches ) ) {
 756                                 $action = urldecode( $matches[2] );
 757                                 if( isset( $wgActionPaths[$action] ) ) {
 758                                         $query = $matches[1];
 759                                         if( isset( $matches[4] ) ) $query .= $matches[4];
 760                                         $url = str_replace( '$1', $dbkey, $wgActionPaths[$action] );
 761                                         if( $query != '' ) $url .= '?' . $query;
 762                                         return $url;
 763                                 }
 764                         }
 765                         if ( $query == '-' ) {
 766                                 $query = '';
 767                         }
 768                         $url = "{$wgScript}?title={$dbkey}&{$query}";
 769                 }
 770
 771                 if ($action == 'render')
 772                         return $wgServer . $url;
 773                 else
 774                         return $url;
 775         }
 776
 777         /**
 778          * Get an HTML-escaped version of the URL form, suitable for
 779          * using in a link, without a server name or fragment
 780          * @param string $query an optional query string
 781          * @return string the URL
 782          * @access public
 783          */
 784         function escapeLocalURL( $query = '' ) {
 785                 return htmlspecialchars( $this->getLocalURL( $query ) );
 786         }
 787
 788         /**
 789          * Get an HTML-escaped version of the URL form, suitable for
 790          * using in a link, including the server name and fragment
 791          *
 792          * @return string the URL
 793          * @param string $query an optional query string
 794          * @access public
 795          */
 796         function escapeFullURL( $query = '' ) {
 797                 return htmlspecialchars( $this->getFullURL( $query ) );
 798         }
 799
 800         /**
 801          * Get the URL form for an internal link.
 802          * - Used in various Squid-related code, in case we have a different
 803          * internal hostname for the server from the exposed one.
 804          *
 805          * @param string $query an optional query string
 806          * @return string the URL
 807          * @access public
 808          */
 809         function getInternalURL( $query = '' ) {
 810                 global $wgInternalServer;
 811                 return $wgInternalServer . $this->getLocalURL( $query );
 812         }
 813
 814         /**
 815          * Get the edit URL for this Title
 816          * @return string the URL, or a null string if this is an
 817          *      interwiki link
 818          * @access public
 819          */
 820         function getEditURL() {
 821                 global $wgServer, $wgScript;
 822
 823                 if ( '' != $this->mInterwiki ) { return ''; }
 824                 $s = $this->getLocalURL( 'action=edit' );
 825
 826                 return $s;
 827         }
 828
 829         /**
 830          * Get the HTML-escaped displayable text form.
 831          * Used for the title field in <a> tags.
 832          * @return string the text, including any prefixes
 833          * @access public
 834          */
 835         function getEscapedText() {
 836                 return htmlspecialchars( $this->getPrefixedText() );
 837         }
 838
 839         /**
 840          * Is this Title interwiki?
 841          * @return boolean
 842          * @access public
 843          */
 844         function isExternal() { return ( '' != $this->mInterwiki ); }
 845
 846         /**
 847          * Does the title correspond to a protected article?
 848          * @param string $what the action the page is protected from,
 849          *      by default checks move and edit
 850          * @return boolean
 851          * @access public
 852          */
 853         function isProtected($action = '') {
 854                 if ( -1 == $this->mNamespace ) { return true; }
 855                 if($action == 'edit' || $action == '') {
 856                         $a = $this->getRestrictions("edit");
 857                         if ( in_array( 'sysop', $a ) ) { return true; }
 858                 }
 859                 if($action == 'move' || $action == '') {
 860                         $a = $this->getRestrictions("move");
 861                         if ( in_array( 'sysop', $a ) ) { return true; }
 862                 }
 863                 return false;
 864         }
 865
 866         /**
 867          * Is $wgUser is watching this page?
 868          * @return boolean
 869          * @access public
 870          */
 871         function userIsWatching() {
 872                 global $wgUser;
 873
 874                 if ( is_null( $this->mWatched ) ) {
 875                         if ( -1 == $this->mNamespace || 0 == $wgUser->getID()) {
 876                                 $this->mWatched = false;
 877                         } else {
 878                                 $this->mWatched = $wgUser->isWatched( $this );
 879                         }
 880                 }
 881                 return $this->mWatched;
 882         }
 883
 884         /**
 885          * Is $wgUser perform $action this page?
 886          * @param string $action action that permission needs to be checked for
 887          * @return boolean
 888          * @access private
 889          */
 890         function userCan($action) {
 891                 $fname = 'Title::userCanEdit';
 892                 wfProfileIn( $fname );
 893
 894                 global $wgUser;
 895                 if( NS_SPECIAL == $this->mNamespace ) {
 896                         wfProfileOut( $fname );
 897                         return false;
 898                 }
 899                 if( NS_MEDIAWIKI == $this->mNamespace &&
 900                     !$wgUser->isAllowed('editinterface') ) {
 901                         wfProfileOut( $fname );
 902                         return false;
 903                 }
 904                 if( $this->mDbkeyform == '_' ) {
 905                         # FIXME: Is this necessary? Shouldn't be allowed anyway...
 906                         wfProfileOut( $fname );
 907                         return false;
 908                 }
 909
 910                 # protect global styles and js
 911                 if ( NS_MEDIAWIKI == $this->mNamespace
 912                  && preg_match("/\\.(css|js)$/", $this->mTextform )
 913                      && !$wgUser->isAllowed('editinterface') ) {
 914                         wfProfileOut( $fname );
 915                         return false;
 916                 }
 917
 918                 # protect css/js subpages of user pages
 919                 # XXX: this might be better using restrictions
 920                 # XXX: Find a way to work around the php bug that prevents using $this->userCanEditCssJsSubpage() from working
 921                 if( NS_USER == $this->mNamespace
 922                         && preg_match("/\\.(css|js)$/", $this->mTextform )
 923                         && !$wgUser->isAllowed('editinterface')
 924                         && !preg_match('/^'.preg_quote($wgUser->getName(), '/').'\//', $this->mTextform) ) {
 925                         wfProfileOut( $fname );
 926                         return false;
 927                 }
 928
 929                 foreach( $this->getRestrictions($action) as $right ) {
 930                         // Backwards compatibility, rewrite sysop -> protect
 931                         if ( $right == 'sysop' ) {
 932                                 $right = 'protect';
 933                         }
 934                         if( '' != $right && !$wgUser->isAllowed( $right ) ) {
 935                                 wfProfileOut( $fname );
 936                                 return false;
 937                         }
 938                 }
 939
 940                 if( $action == 'move' && !$this->isMovable() ) {
 941                         wfProfileOut( $fname );
 942                         return false;
 943                 }
 944
 945                 wfProfileOut( $fname );
 946                 return true;
 947         }
 948
 949         /**
 950          * Can $wgUser edit this page?
 951          * @return boolean
 952          * @access public
 953          */
 954         function userCanEdit() {
 955                 return $this->userCan('edit');
 956         }
 957
 958         /**
 959          * Can $wgUser move this page?
 960          * @return boolean
 961          * @access public
 962          */
 963         function userCanMove() {
 964                 return $this->userCan('move');
 965         }
 966
 967         /**
 968          * Would anybody with sufficient privileges be able to move this page?
 969          * Some pages just aren't movable.
 970          *
 971          * @return boolean
 972          * @access public
 973          */
 974         function isMovable() {
 975                 return Namespace::isMovable( $this->getNamespace() )
 976                         && $this->getInterwiki() == '';
 977         }
 978
 979         /**
 980          * Can $wgUser read this page?
 981          * @return boolean
 982          * @access public
 983          */
 984         function userCanRead() {
 985                 global $wgUser;
 986
 987                 if( $wgUser->isAllowed('read') ) {
 988                         return true;
 989                 } else {
 990                         global $wgWhitelistRead;
 991
 992                         /** If anon users can create an account,
 993                             they need to reach the login page first! */
 994                         if( $wgUser->isAllowed( 'createaccount' )
 995                             && $this->getNamespace() == NS_SPECIAL
 996                             && $this->getText() == 'Userlogin' ) {
 997                                 return true;
 998                         }
 999
1000                         /** some pages are explicitly allowed */
1001                         $name = $this->getPrefixedText();
1002                         if( $wgWhitelistRead && in_array( $name, $wgWhitelistRead ) ) {
1003                                 return true;
1004                         }
1005
1006                         # Compatibility with old settings
1007                         if( $wgWhitelistRead && $this->getNamespace() == NS_MAIN ) {
1008                                 if( in_array( ':' . $name, $wgWhitelistRead ) ) {
1009                                         return true;
1010                                 }
1011                         }
1012                 }
1013                 return false;
1014         }
1015
1016         /**
1017          * Is this a talk page of some sort?
1018          * @return bool
1019          * @access public
1020          */
1021         function isTalkPage() {
1022                 return Namespace::isTalk( $this->getNamespace() );
1023         }
1024
1025         /**
1026          * Is this a .css or .js subpage of a user page?
1027          * @return bool
1028          * @access public
1029          */
1030         function isCssJsSubpage() {
1031                 return ( NS_USER == $this->mNamespace and preg_match("/\\.(css|js)$/", $this->mTextform ) );
1032         }
1033         /**
1034          * Is this a .css subpage of a user page?
1035          * @return bool
1036          * @access public
1037          */
1038         function isCssSubpage() {
1039                 return ( NS_USER == $this->mNamespace and preg_match("/\\.css$/", $this->mTextform ) );
1040         }
1041         /**
1042          * Is this a .js subpage of a user page?
1043          * @return bool
1044          * @access public
1045          */
1046         function isJsSubpage() {
1047                 return ( NS_USER == $this->mNamespace and preg_match("/\\.js$/", $this->mTextform ) );
1048         }
1049         /**
1050          * Protect css/js subpages of user pages: can $wgUser edit
1051          * this page?
1052          *
1053          * @return boolean
1054          * @todo XXX: this might be better using restrictions
1055          * @access public
1056          */
1057         function userCanEditCssJsSubpage() {
1058                 global $wgUser;
1059                 return ( $wgUser->isAllowed('editinterface') or preg_match('/^'.preg_quote($wgUser->getName(), '/').'\//', $this->mTextform) );
1060         }
1061
1062         /**
1063          * Loads a string into mRestrictions array
1064          * @param string $res restrictions in string format
1065          * @access public
1066          */
1067         function loadRestrictions( $res ) {
1068                 foreach( explode( ':', trim( $res ) ) as $restrict ) {
1069                         $temp = explode( '=', trim( $restrict ) );
1070                         if(count($temp) == 1) {
1071                                 // old format should be treated as edit/move restriction
1072                                 $this->mRestrictions["edit"] = explode( ',', trim( $temp[0] ) );
1073                                 $this->mRestrictions["move"] = explode( ',', trim( $temp[0] ) );
1074                         } else {
1075                                 $this->mRestrictions[$temp[0]] = explode( ',', trim( $temp[1] ) );
1076                         }
1077                 }
1078                 $this->mRestrictionsLoaded = true;
1079         }
1080
1081         /**
1082          * Accessor/initialisation for mRestrictions
1083          * @param string $action action that permission needs to be checked for
1084          * @return array the array of groups allowed to edit this article
1085          * @access public
1086          */
1087         function getRestrictions($action) {
1088                 $id = $this->getArticleID();
1089                 if ( 0 == $id ) { return array(); }
1090
1091                 if ( ! $this->mRestrictionsLoaded ) {
1092                         $dbr =& wfGetDB( DB_SLAVE );
1093                         $res = $dbr->selectField( 'page', 'page_restrictions', 'page_id='.$id );
1094                         $this->loadRestrictions( $res );
1095                 }
1096                 if( isset( $this->mRestrictions[$action] ) ) {
1097                         return $this->mRestrictions[$action];
1098                 }
1099                 return array();
1100         }
1101
1102         /**
1103          * Is there a version of this page in the deletion archive?
1104          * @return int the number of archived revisions
1105          * @access public
1106          */
1107         function isDeleted() {
1108                 $fname = 'Title::isDeleted';
1109                 if ( $this->getNamespace() < 0 ) {
1110                         $n = 0;
1111                 } else {
1112                         $dbr =& wfGetDB( DB_SLAVE );
1113                         $n = $dbr->selectField( 'archive', 'COUNT(*)', array( 'ar_namespace' => $this->getNamespace(),
1114                                 'ar_title' => $this->getDBkey() ), $fname );
1115                 }
1116                 return (int)$n;
1117         }
1118
1119         /**
1120          * Get the article ID for this Title from the link cache,
1121          * adding it if necessary
1122          * @param int $flags a bit field; may be GAID_FOR_UPDATE to select
1123          *      for update
1124          * @return int the ID
1125          * @access public
1126          */
1127         function getArticleID( $flags = 0 ) {
1128                 global $wgLinkCache;
1129
1130                 if ( $flags & GAID_FOR_UPDATE ) {
1131                         $oldUpdate = $wgLinkCache->forUpdate( true );
1132                         $this->mArticleID = $wgLinkCache->addLinkObj( $this );
1133                         $wgLinkCache->forUpdate( $oldUpdate );
1134                 } else {
1135                         if ( -1 == $this->mArticleID ) {
1136                                 $this->mArticleID = $wgLinkCache->addLinkObj( $this );
1137                         }
1138                 }
1139                 return $this->mArticleID;
1140         }
1141
1142         function getLatestRevID() {
1143                 if ($this->mLatestID !== false)
1144                         return $this->mLatestID;
1145
1146                 $db =& wfGetDB(DB_SLAVE);
1147                 return $this->mLatestID = $db->selectField( 'revision',
1148                         "max(rev_id)",
1149                         array('rev_page' => $this->getArticleID()),
1150                         'Title::getLatestRevID' );
1151         }
1152
1153         /**
1154          * This clears some fields in this object, and clears any associated
1155          * keys in the "bad links" section of $wgLinkCache.
1156          *
1157          * - This is called from Article::insertNewArticle() to allow
1158          * loading of the new page_id. It's also called from
1159          * Article::doDeleteArticle()
1160          *
1161          * @param int $newid the new Article ID
1162          * @access public
1163          */
1164         function resetArticleID( $newid ) {
1165                 global $wgLinkCache;
1166                 $wgLinkCache->clearBadLink( $this->getPrefixedDBkey() );
1167
1168                 if ( 0 == $newid ) { $this->mArticleID = -1; }
1169                 else { $this->mArticleID = $newid; }
1170                 $this->mRestrictionsLoaded = false;
1171                 $this->mRestrictions = array();
1172         }
1173
1174         /**
1175          * Updates page_touched for this page; called from LinksUpdate.php
1176          * @return bool true if the update succeded
1177          * @access public
1178          */
1179         function invalidateCache() {
1180                 global $wgUseFileCache;
1181
1182                 if ( wfReadOnly() ) {
1183                         return;
1184                 }
1185
1186                 $now = wfTimestampNow();
1187                 $dbw =& wfGetDB( DB_MASTER );
1188                 $success = $dbw->update( 'page',
1189                         array( /* SET */
1190                                 'page_touched' => $dbw->timestamp()
1191                         ), array( /* WHERE */
1192                                 'page_namespace' => $this->getNamespace() ,
1193                                 'page_title' => $this->getDBkey()
1194                         ), 'Title::invalidateCache'
1195                 );
1196
1197                 if ($wgUseFileCache) {
1198                         $cache = new CacheManager($this);
1199                         @unlink($cache->fileCacheName());
1200                 }
1201
1202                 return $success;
1203         }
1204
1205         /**
1206          * Prefix some arbitrary text with the namespace or interwiki prefix
1207          * of this object
1208          *
1209          * @param string $name the text
1210          * @return string the prefixed text
1211          * @access private
1212          */
1213         /* private */ function prefix( $name ) {
1214                 global $wgContLang;
1215
1216                 $p = '';
1217                 if ( '' != $this->mInterwiki ) {
1218                         $p = $this->mInterwiki . ':';
1219                 }
1220                 if ( 0 != $this->mNamespace ) {
1221                         $p .= $wgContLang->getNsText( $this->mNamespace ) . ':';
1222                 }
1223                 return $p . $name;
1224         }
1225
1226         /**
1227          * Secure and split - main initialisation function for this object
1228          *
1229          * Assumes that mDbkeyform has been set, and is urldecoded
1230          * and uses underscores, but not otherwise munged.  This function
1231          * removes illegal characters, splits off the interwiki and
1232          * namespace prefixes, sets the other forms, and canonicalizes
1233          * everything.
1234          * @return bool true on success
1235          * @access private
1236          */
1237         /* private */ function secureAndSplit() {
1238                 global $wgContLang, $wgLocalInterwiki, $wgCapitalLinks;
1239                 $fname = 'Title::secureAndSplit';
1240                 wfProfileIn( $fname );
1241
1242                 # Initialisation
1243                 static $rxTc = false;
1244                 if( !$rxTc ) {
1245                         # % is needed as well
1246                         $rxTc = '/[^' . Title::legalChars() . ']|%[0-9A-Fa-f]{2}/S';
1247                 }
1248
1249                 $this->mInterwiki = $this->mFragment = '';
1250                 $this->mNamespace = $this->mDefaultNamespace; # Usually NS_MAIN
1251
1252                 # Clean up whitespace
1253                 #
1254                 $t = preg_replace( '/[ _]+/', '_', $this->mDbkeyform );
1255                 $t = trim( $t, '_' );
1256
1257                 if ( '' == $t ) {
1258                         wfProfileOut( $fname );
1259                         return false;
1260                 }
1261
1262                 if( false !== strpos( $t, UTF8_REPLACEMENT ) ) {
1263                         # Contained illegal UTF-8 sequences or forbidden Unicode chars.
1264                         wfProfileOut( $fname );
1265                         return false;
1266                 }
1267
1268                 $this->mDbkeyform = $t;
1269
1270                 # Initial colon indicating main namespace
1271                 if ( ':' == $t{0} ) {
1272                         $r = substr( $t, 1 );
1273                         $this->mNamespace = NS_MAIN;
1274                 } else {
1275                         # Namespace or interwiki prefix
1276                         $firstPass = true;
1277                         do {
1278                                 if ( preg_match( "/^(.+?)_*:_*(.*)$/S", $t, $m ) ) {
1279                                         $p = $m[1];
1280                                         $lowerNs = strtolower( $p );
1281                                         if ( $ns = Namespace::getCanonicalIndex( $lowerNs ) ) {
1282                                                 # Canonical namespace
1283                                                 $t = $m[2];
1284                                                 $this->mNamespace = $ns;
1285                                         } elseif ( $ns = $wgContLang->getNsIndex( $lowerNs )) {
1286                                                 # Ordinary namespace
1287                                                 $t = $m[2];
1288                                                 $this->mNamespace = $ns;
1289                                         } elseif( $this->getInterwikiLink( $p ) ) {
1290                                                 if( !$firstPass ) {
1291                                                         # Can't make a local interwiki link to an interwiki link.
1292                                                         # That's just crazy!
1293                                                         wfProfileOut( $fname );
1294                                                         return false;
1295                                                 }
1296
1297                                                 # Interwiki link
1298                                                 $t = $m[2];
1299                                                 $this->mInterwiki = $p;
1300
1301                                                 # Redundant interwiki prefix to the local wiki
1302                                                 if ( 0 == strcasecmp( $this->mInterwiki, $wgLocalInterwiki ) ) {
1303                                                         if( $t == '' ) {
1304                                                                 # Can't have an empty self-link
1305                                                                 wfProfileOut( $fname );
1306                                                                 return false;
1307                                                         }
1308                                                         $this->mInterwiki = '';
1309                                                         $firstPass = false;
1310                                                         # Do another namespace split...
1311                                                         continue;
1312                                                 }
1313                                         }
1314                                         # If there's no recognized interwiki or namespace,
1315                                         # then let the colon expression be part of the title.
1316                                 }
1317                                 break;
1318                         } while( true );
1319                         $r = $t;
1320                 }
1321
1322                 # We already know that some pages won't be in the database!
1323                 #
1324                 if ( '' != $this->mInterwiki || -1 == $this->mNamespace ) {
1325                         $this->mArticleID = 0;
1326                 }
1327                 $f = strstr( $r, '#' );
1328                 if ( false !== $f ) {
1329                         $this->mFragment = substr( $f, 1 );
1330                         $r = substr( $r, 0, strlen( $r ) - strlen( $f ) );
1331                         # remove whitespace again: prevents "Foo_bar_#"
1332                         # becoming "Foo_bar_"
1333                         $r = preg_replace( '/_*$/', '', $r );
1334                 }
1335
1336                 # Reject illegal characters.
1337                 #
1338                 if( preg_match( $rxTc, $r ) ) {
1339                         wfProfileOut( $fname );
1340                         return false;
1341                 }
1342
1343                 /**
1344                  * Pages with "/./" or "/../" appearing in the URLs will
1345                  * often be unreachable due to the way web browsers deal
1346                  * with 'relative' URLs. Forbid them explicitly.
1347                  */
1348                 if ( strpos( $r, '.' ) !== false &&
1349                      ( $r === '.' || $r === '..' ||
1350                        strpos( $r, './' ) === 0  ||
1351                        strpos( $r, '../' ) === 0 ||
1352                        strpos( $r, '/./' ) !== false ||
1353                        strpos( $r, '/../' ) !== false ) )
1354                 {
1355                         wfProfileOut( $fname );
1356                         return false;
1357                 }
1358
1359                 # We shouldn't need to query the DB for the size.
1360                 #$maxSize = $dbr->textFieldSize( 'page', 'page_title' );
1361                 if ( strlen( $r ) > 255 ) {
1362                         wfProfileOut( $fname );
1363                         return false;
1364                 }
1365
1366                 /**
1367                  * Normally, all wiki links are forced to have
1368                  * an initial capital letter so [[foo]] and [[Foo]]
1369                  * point to the same place.
1370                  *
1371                  * Don't force it for interwikis, since the other
1372                  * site might be case-sensitive.
1373                  */
1374                 if( $wgCapitalLinks && $this->mInterwiki == '') {
1375                         $t = $wgContLang->ucfirst( $r );
1376                 } else {
1377                         $t = $r;
1378                 }
1379
1380                 /**
1381                  * Can't make a link to a namespace alone...
1382                  * "empty" local links can only be self-links
1383                  * with a fragment identifier.
1384                  */
1385                 if( $t == '' &&
1386                         $this->mInterwiki == '' &&
1387                         $this->mNamespace != NS_MAIN ) {
1388                         wfProfileOut( $fname );
1389                         return false;
1390                 }
1391
1392                 # Fill fields
1393                 $this->mDbkeyform = $t;
1394                 $this->mUrlform = wfUrlencode( $t );
1395
1396                 $this->mTextform = str_replace( '_', ' ', $t );
1397
1398                 wfProfileOut( $fname );
1399                 return true;
1400         }
1401
1402         /**
1403          * Get a Title object associated with the talk page of this article
1404          * @return Title the object for the talk page
1405          * @access public
1406          */
1407         function getTalkPage() {
1408                 return Title::makeTitle( Namespace::getTalk( $this->getNamespace() ), $this->getDBkey() );
1409         }
1410
1411         /**
1412          * Get a title object associated with the subject page of this
1413          * talk page
1414          *
1415          * @return Title the object for the subject page
1416          * @access public
1417          */
1418         function getSubjectPage() {
1419                 return Title::makeTitle( Namespace::getSubject( $this->getNamespace() ), $this->getDBkey() );
1420         }
1421
1422         /**
1423          * Get an array of Title objects linking to this Title
1424          * Also stores the IDs in the link cache.
1425          *
1426          * @param string $options may be FOR UPDATE
1427          * @return array the Title objects linking here
1428          * @access public
1429          */
1430         function getLinksTo( $options = '' ) {
1431                 global $wgLinkCache;
1432                 $id = $this->getArticleID();
1433
1434                 if ( $options ) {
1435                         $db =& wfGetDB( DB_MASTER );
1436                 } else {
1437                         $db =& wfGetDB( DB_SLAVE );
1438                 }
1439
1440                 $res = $db->select( array( 'page', 'pagelinks' ),
1441                         array( 'page_namespace', 'page_title', 'page_id' ),
1442                         array(
1443                                 'pl_from=page_id',
1444                                 'pl_namespace' => $this->getNamespace(),
1445                                 'pl_title'     => $this->getDbKey() ),
1446                         'Title::getLinksTo',
1447                         $options );
1448
1449                 $retVal = array();
1450                 if ( $db->numRows( $res ) ) {
1451                         while ( $row = $db->fetchObject( $res ) ) {
1452                                 if ( $titleObj = Title::makeTitle( $row->page_namespace, $row->page_title ) ) {
1453                                         $wgLinkCache->addGoodLinkObj( $row->page_id, $titleObj );
1454                                         $retVal[] = $titleObj;
1455                                 }
1456                         }
1457                 }
1458                 $db->freeResult( $res );
1459                 return $retVal;
1460         }
1461
1462         /**
1463          * Get an array of Title objects referring to non-existent articles linked from this page
1464          *
1465          * @param string $options may be FOR UPDATE
1466          * @return array the Title objects
1467          * @access public
1468          */
1469         function getBrokenLinksFrom( $options = '' ) {
1470                 global $wgLinkCache;
1471
1472                 if ( $options ) {
1473                         $db =& wfGetDB( DB_MASTER );
1474                 } else {
1475                         $db =& wfGetDB( DB_SLAVE );
1476                 }
1477
1478                 $res = $db->safeQuery(
1479                           "SELECT pl_namespace, pl_title
1480                              FROM !
1481                         LEFT JOIN !
1482                                ON pl_namespace=page_namespace
1483                               AND pl_title=page_title
1484                             WHERE pl_from=?
1485                               AND page_namespace IS NULL
1486                                   !",
1487                         $db->tableName( 'pagelinks' ),
1488                         $db->tableName( 'page' ),
1489                         $this->getArticleId(),
1490                         $options );
1491
1492                 $retVal = array();
1493                 if ( $db->numRows( $res ) ) {
1494                         while ( $row = $db->fetchObject( $res ) ) {
1495                                 $retVal[] = Title::makeTitle( $row->pl_namespace, $row->pl_title );
1496                         }
1497                 }
1498                 $db->freeResult( $res );
1499                 return $retVal;
1500         }
1501
1502
1503         /**
1504          * Get a list of URLs to purge from the Squid cache when this
1505          * page changes
1506          *
1507          * @return array the URLs
1508          * @access public
1509          */
1510         function getSquidURLs() {
1511                 return array(
1512                         $this->getInternalURL(),
1513                         $this->getInternalURL( 'action=history' )
1514                 );
1515         }
1516
1517         /**
1518          * Move this page without authentication
1519          * @param Title &$nt the new page Title
1520          * @access public
1521          */
1522         function moveNoAuth( &$nt ) {
1523                 return $this->moveTo( $nt, false );
1524         }
1525
1526         /**
1527          * Check whether a given move operation would be valid.
1528          * Returns true if ok, or a message key string for an error message
1529          * if invalid. (Scarrrrry ugly interface this.)
1530          * @param Title &$nt the new title
1531          * @param bool $auth indicates whether $wgUser's permissions
1532          *      should be checked
1533          * @return mixed true on success, message name on failure
1534          * @access public
1535          */
1536         function isValidMoveOperation( &$nt, $auth = true, $reason = '' ) {
1537                 global $wgUser;
1538                 if( !$this or !$nt ) {
1539                         return 'badtitletext';
1540                 }
1541                 if( $this->equals( $nt ) ) {
1542                         return 'selfmove';
1543                 }
1544                 if( !$this->isMovable() || !$nt->isMovable() ) {
1545                         return 'immobile_namespace';
1546                 }
1547
1548                 $fname = 'Title::move';
1549                 $oldid = $this->getArticleID();
1550                 $newid = $nt->getArticleID();
1551
1552                 if ( strlen( $nt->getDBkey() ) < 1 ) {
1553                         return 'articleexists';
1554                 }
1555                 if ( ( '' == $this->getDBkey() ) ||
1556                          ( !$oldid ) ||
1557                      ( '' == $nt->getDBkey() ) ) {
1558                         return 'badarticleerror';
1559                 }
1560
1561                 if ( $auth && (
1562                                 !$this->userCanEdit() || !$nt->userCanEdit() ||
1563                                 !$this->userCanMove() || !$nt->userCanMove() ) ) {
1564                         return 'protectedpage';
1565                 }
1566
1567                 # The move is allowed only if (1) the target doesn't exist, or
1568                 # (2) the target is a redirect to the source, and has no history
1569                 # (so we can undo bad moves right after they're done).
1570
1571                 if ( 0 != $newid ) { # Target exists; check for validity
1572                         if ( ! $this->isValidMoveTarget( $nt ) ) {
1573                                 return 'articleexists';
1574                         }
1575                 }
1576                 return true;
1577         }
1578
1579         /**
1580          * Move a title to a new location
1581          * @param Title &$nt the new title
1582          * @param bool $auth indicates whether $wgUser's permissions
1583          *      should be checked
1584          * @return mixed true on success, message name on failure
1585          * @access public
1586          */
1587         function moveTo( &$nt, $auth = true, $reason = '' ) {
1588                 $err = $this->isValidMoveOperation( $nt, $auth, $reason );
1589                 if( is_string( $err ) ) {
1590                         return $err;
1591                 }
1592
1593                 $pageid = $this->getArticleID();
1594                 if( $nt->exists() ) {
1595                         $this->moveOverExistingRedirect( $nt, $reason );
1596                         $pageCountChange = 0;
1597                 } else { # Target didn't exist, do normal move.
1598                         $this->moveToNewTitle( $nt, $newid, $reason );
1599                         $pageCountChange = 1;
1600                 }
1601                 $redirid = $this->getArticleID();
1602
1603                 # Fixing category links (those without piped 'alternate' names) to be sorted under the new title
1604                 $dbw =& wfGetDB( DB_MASTER );
1605                 $categorylinks = $dbw->tableName( 'categorylinks' );
1606                 $sql = "UPDATE $categorylinks SET cl_sortkey=" . $dbw->addQuotes( $nt->getPrefixedText() ) .
1607                         " WHERE cl_from=" . $dbw->addQuotes( $pageid ) .
1608                         " AND cl_sortkey=" . $dbw->addQuotes( $this->getPrefixedText() );
1609                 $dbw->query( $sql, 'SpecialMovepage::doSubmit' );
1610
1611                 # Update watchlists
1612
1613                 $oldnamespace = $this->getNamespace() & ~1;
1614                 $newnamespace = $nt->getNamespace() & ~1;
1615                 $oldtitle = $this->getDBkey();
1616                 $newtitle = $nt->getDBkey();
1617
1618                 if( $oldnamespace != $newnamespace || $oldtitle != $newtitle ) {
1619                         WatchedItem::duplicateEntries( $this, $nt );
1620                 }
1621
1622                 # Update search engine
1623                 $u = new SearchUpdate( $pageid, $nt->getPrefixedDBkey() );
1624                 $u->doUpdate();
1625                 $u = new SearchUpdate( $redirid, $this->getPrefixedDBkey(), '' );
1626                 $u->doUpdate();
1627
1628                 # Update site_stats
1629                 if ( $this->getNamespace() == NS_MAIN and $nt->getNamespace() != NS_MAIN ) {
1630                         # Moved out of main namespace
1631                         # not viewed, edited, removing
1632                         $u = new SiteStatsUpdate( 0, 1, -1, $pageCountChange);
1633                 } elseif ( $this->getNamespace() != NS_MAIN and $nt->getNamespace() == NS_MAIN ) {
1634                         # Moved into main namespace
1635                         # not viewed, edited, adding
1636                         $u = new SiteStatsUpdate( 0, 1, +1, $pageCountChange );
1637                 } elseif ( $pageCountChange ) {
1638                         # Added redirect
1639                         $u = new SiteStatsUpdate( 0, 0, 0, 1 );
1640                 } else{
1641                         $u = false;
1642                 }
1643                 if ( $u ) {
1644                         $u->doUpdate();
1645                 }
1646
1647                 wfRunHooks( 'TitleMoveComplete', array( &$this, &$nt, &$wgUser, $pageid, $redirid ) );
1648                 return true;
1649         }
1650
1651         /**
1652          * Move page to a title which is at present a redirect to the
1653          * source page
1654          *
1655          * @param Title &$nt the page to move to, which should currently
1656          *      be a redirect
1657          * @access private
1658          */
1659         function moveOverExistingRedirect( &$nt, $reason = '' ) {
1660                 global $wgUser, $wgLinkCache, $wgUseSquid, $wgMwRedir;
1661                 $fname = 'Title::moveOverExistingRedirect';
1662                 $comment = wfMsgForContent( '1movedto2', $this->getPrefixedText(), $nt->getPrefixedText() );
1663
1664                 if ( $reason ) {
1665                         $comment .= ": $reason";
1666                 }
1667
1668                 $now = wfTimestampNow();
1669                 $rand = wfRandom();
1670                 $newid = $nt->getArticleID();
1671                 $oldid = $this->getArticleID();
1672                 $dbw =& wfGetDB( DB_MASTER );
1673                 $links = $dbw->tableName( 'links' );
1674
1675                 # Delete the old redirect. We don't save it to history since
1676                 # by definition if we've got here it's rather uninteresting.
1677                 # We have to remove it so that the next step doesn't trigger
1678                 # a conflict on the unique namespace+title index...
1679                 $dbw->delete( 'page', array( 'page_id' => $newid ), $fname );
1680
1681                 # Save a null revision in the page's history notifying of the move
1682                 $nullRevision = Revision::newNullRevision( $dbw, $oldid,
1683                         wfMsgForContent( '1movedto2', $this->getPrefixedText(), $nt->getPrefixedText() ),
1684                         true );
1685                 $nullRevId = $nullRevision->insertOn( $dbw );
1686
1687                 # Change the name of the target page:
1688                 $dbw->update( 'page',
1689                         /* SET */ array(
1690                                 'page_touched'   => $dbw->timestamp($now),
1691                                 'page_namespace' => $nt->getNamespace(),
1692                                 'page_title'     => $nt->getDBkey(),
1693                                 'page_latest'    => $nullRevId,
1694                         ),
1695                         /* WHERE */ array( 'page_id' => $oldid ),
1696                         $fname
1697                 );
1698                 $wgLinkCache->clearLink( $nt->getPrefixedDBkey() );
1699
1700                 # Recreate the redirect, this time in the other direction.
1701                 $redirectText = $wgMwRedir->getSynonym( 0 ) . ' [[' . $nt->getPrefixedText() . "]]\n";
1702                 $redirectArticle = new Article( $this );
1703                 $newid = $redirectArticle->insertOn( $dbw );
1704                 $redirectRevision = new Revision( array(
1705                         'page'    => $newid,
1706                         'comment' => $comment,
1707                         'text'    => $redirectText ) );
1708                 $revid = $redirectRevision->insertOn( $dbw );
1709                 $redirectArticle->updateRevisionOn( $dbw, $redirectRevision, 0 );
1710                 $wgLinkCache->clearLink( $this->getPrefixedDBkey() );
1711
1712                 # Log the move
1713                 $log = new LogPage( 'move' );
1714                 $log->addEntry( 'move_redir', $this, $reason, array( 1 => $nt->getPrefixedText() ) );
1715
1716                 # Now, we record the link from the redirect to the new title.
1717                 # It should have no other outgoing links...
1718                 $dbw->delete( 'pagelinks', array( 'pl_from' => $newid ), $fname );
1719                 $dbw->insert( 'pagelinks',
1720                         array(
1721                                 'pl_from'      => $newid,
1722                                 'pl_namespace' => $nt->getNamespace(),
1723                                 'pl_title'     => $nt->getDbKey() ),
1724                         $fname );
1725
1726                 # Purge squid
1727                 if ( $wgUseSquid ) {
1728                         $urls = array_merge( $nt->getSquidURLs(), $this->getSquidURLs() );
1729                         $u = new SquidUpdate( $urls );
1730                         $u->doUpdate();
1731                 }
1732         }
1733
1734         /**
1735          * Move page to non-existing title.
1736          * @param Title &$nt the new Title
1737          * @param int &$newid set to be the new article ID
1738          * @access private
1739          */
1740         function moveToNewTitle( &$nt, &$newid, $reason = '' ) {
1741                 global $wgUser, $wgLinkCache, $wgUseSquid;
1742                 global $wgMwRedir;
1743                 $fname = 'MovePageForm::moveToNewTitle';
1744                 $comment = wfMsgForContent( '1movedto2', $this->getPrefixedText(), $nt->getPrefixedText() );
1745                 if ( $reason ) {
1746                         $comment .= ": $reason";
1747                 }
1748
1749                 $newid = $nt->getArticleID();
1750                 $oldid = $this->getArticleID();
1751                 $dbw =& wfGetDB( DB_MASTER );
1752                 $now = $dbw->timestamp();
1753                 wfSeedRandom();
1754                 $rand = wfRandom();
1755
1756                 # Save a null revision in the page's history notifying of the move
1757                 $nullRevision = Revision::newNullRevision( $dbw, $oldid,
1758                         wfMsgForContent( '1movedto2', $this->getPrefixedText(), $nt->getPrefixedText() ),
1759                         true );
1760                 $nullRevId = $nullRevision->insertOn( $dbw );
1761
1762                 # Rename cur entry
1763                 $dbw->update( 'page',
1764                         /* SET */ array(
1765                                 'page_touched'   => $now,
1766                                 'page_namespace' => $nt->getNamespace(),
1767                                 'page_title'     => $nt->getDBkey(),
1768                                 'page_latest'    => $nullRevId,
1769                         ),
1770                         /* WHERE */ array( 'page_id' => $oldid ),
1771                         $fname
1772                 );
1773
1774                 $wgLinkCache->clearLink( $nt->getPrefixedDBkey() );
1775
1776                 # Insert redirect
1777                 $redirectText = $wgMwRedir->getSynonym( 0 ) . ' [[' . $nt->getPrefixedText() . "]]\n";
1778                 $redirectArticle = new Article( $this );
1779                 $newid = $redirectArticle->insertOn( $dbw );
1780                 $redirectRevision = new Revision( array(
1781                         'page'    => $newid,
1782                         'comment' => $comment,
1783                         'text'    => $redirectText ) );
1784                 $revid = $redirectRevision->insertOn( $dbw );
1785                 $redirectArticle->updateRevisionOn( $dbw, $redirectRevision, 0 );
1786                 $wgLinkCache->clearLink( $this->getPrefixedDBkey() );
1787
1788                 # Log the move
1789                 $log = new LogPage( 'move' );
1790                 $log->addEntry( 'move', $this, $reason, array( 1 => $nt->getPrefixedText()) );
1791
1792                 # Purge caches as per article creation
1793                 Article::onArticleCreate( $nt );
1794
1795                 # Record the just-created redirect's linking to the page
1796                 $dbw->insert( 'pagelinks',
1797                         array(
1798                                 'pl_from'      => $newid,
1799                                 'pl_namespace' => $nt->getNamespace(),
1800                                 'pl_title'     => $nt->getDBkey() ),
1801                         $fname );
1802
1803                 # Non-existent target may have had broken links to it; these must
1804                 # now be touched to update link coloring.
1805                 $nt->touchLinks();
1806
1807                 # Purge old title from squid
1808                 # The new title, and links to the new title, are purged in Article::onArticleCreate()
1809                 $titles = $nt->getLinksTo();
1810                 if ( $wgUseSquid ) {
1811                         $urls = $this->getSquidURLs();
1812                         foreach ( $titles as $linkTitle ) {
1813                                 $urls[] = $linkTitle->getInternalURL();
1814                         }
1815                         $u = new SquidUpdate( $urls );
1816                         $u->doUpdate();
1817                 }
1818         }
1819
1820         /**
1821          * Checks if $this can be moved to a given Title
1822          * - Selects for update, so don't call it unless you mean business
1823          *
1824          * @param Title &$nt the new title to check
1825          * @access public
1826          */
1827         function isValidMoveTarget( $nt ) {
1828
1829                 $fname = 'Title::isValidMoveTarget';
1830                 $dbw =& wfGetDB( DB_MASTER );
1831
1832                 # Is it a redirect?
1833                 $id  = $nt->getArticleID();
1834                 $obj = $dbw->selectRow( array( 'page', 'revision', 'text'),
1835                         array( 'page_is_redirect','old_text' ),
1836                         array( 'page_id' => $id, 'page_latest=rev_id', 'rev_text_id=old_id' ),
1837                         $fname, 'FOR UPDATE' );
1838
1839                 if ( !$obj || 0 == $obj->page_is_redirect ) {
1840                         # Not a redirect
1841                         return false;
1842                 }
1843
1844                 # Does the redirect point to the source?
1845                 if ( preg_match( "/\\[\\[\\s*([^\\]\\|]*)]]/", $obj->old_text, $m ) ) {
1846                         $redirTitle = Title::newFromText( $m[1] );
1847                         if( !is_object( $redirTitle ) ||
1848                                 $redirTitle->getPrefixedDBkey() != $this->getPrefixedDBkey() ) {
1849                                 return false;
1850                         }
1851                 }
1852
1853                 # Does the article have a history?
1854                 $row = $dbw->selectRow( array( 'page', 'revision'),
1855                         array( 'rev_id' ),
1856                         array( 'page_namespace' => $nt->getNamespace(),
1857                                 'page_title' => $nt->getDBkey(),
1858                                 'page_id=rev_page AND page_latest != rev_id'
1859                         ), $fname, 'FOR UPDATE'
1860                 );
1861
1862                 # Return true if there was no history
1863                 return $row === false;
1864         }
1865
1866         /**
1867          * Create a redirect; fails if the title already exists; does
1868          * not notify RC
1869          *
1870          * @param Title $dest the destination of the redirect
1871          * @param string $comment the comment string describing the move
1872          * @return bool true on success
1873          * @access public
1874          */
1875         function createRedirect( $dest, $comment ) {
1876                 global $wgUser;
1877                 if ( $this->getArticleID() ) {
1878                         return false;
1879                 }
1880
1881                 $fname = 'Title::createRedirect';
1882                 $dbw =& wfGetDB( DB_MASTER );
1883
1884                 $article = new Article( $this );
1885                 $newid = $article->insertOn( $dbw );
1886                 $revision = new Revision( array(
1887                         'page'      => $newid,
1888                         'comment'   => $comment,
1889                         'text'      => "#REDIRECT [[" . $dest->getPrefixedText() . "]]\n",
1890                         ) );
1891                 $revisionId = $revision->insertOn( $dbw );
1892                 $article->updateRevisionOn( $dbw, $revision, 0 );
1893
1894                 # Link table
1895                 $dbw->insert( 'pagelinks',
1896                         array(
1897                                 'pl_from'      => $newid,
1898                                 'pl_namespace' => $dest->getNamespace(),
1899                                 'pl_title'     => $dest->getDbKey()
1900                         ), $fname
1901                 );
1902
1903                 Article::onArticleCreate( $this );
1904                 return true;
1905         }
1906
1907         /**
1908          * Get categories to which this Title belongs and return an array of
1909          * categories' names.
1910          *
1911          * @return array an array of parents in the form:
1912          *      $parent => $currentarticle
1913          * @access public
1914          */
1915         function getParentCategories() {
1916                 global $wgContLang,$wgUser;
1917
1918                 $titlekey = $this->getArticleId();
1919                 $sk =& $wgUser->getSkin();
1920                 $parents = array();
1921                 $dbr =& wfGetDB( DB_SLAVE );
1922                 $categorylinks = $dbr->tableName( 'categorylinks' );
1923
1924                 # NEW SQL
1925                 $sql = "SELECT * FROM $categorylinks"
1926                      ." WHERE cl_from='$titlekey'"
1927                          ." AND cl_from <> '0'"
1928                          ." ORDER BY cl_sortkey";
1929
1930                 $res = $dbr->query ( $sql ) ;
1931
1932                 if($dbr->numRows($res) > 0) {
1933                         while ( $x = $dbr->fetchObject ( $res ) )
1934                                 //$data[] = Title::newFromText($wgContLang->getNSText ( NS_CATEGORY ).':'.$x->cl_to);
1935                                 $data[$wgContLang->getNSText ( NS_CATEGORY ).':'.$x->cl_to] = $this->getFullText();
1936                         $dbr->freeResult ( $res ) ;
1937                 } else {
1938                         $data = '';
1939                 }
1940                 return $data;
1941         }
1942
1943         /**
1944          * Get a tree of parent categories
1945          * @param array $children an array with the children in the keys, to check for circular refs
1946          * @return array
1947          * @access public
1948          */
1949         function getParentCategoryTree( $children = array() ) {
1950                 $parents = $this->getParentCategories();
1951
1952                 if($parents != '') {
1953                         foreach($parents as $parent => $current)
1954                         {
1955                                 if ( array_key_exists( $parent, $children ) ) {
1956                                         # Circular reference
1957                                         $stack[$parent] = array();
1958                                 } else {
1959                                         $nt = Title::newFromText($parent);
1960                                         $stack[$parent] = $nt->getParentCategoryTree( $children + array($parent => 1) );
1961                                 }
1962                         }
1963                         return $stack;
1964                 } else {
1965                         return array();
1966                 }
1967         }
1968
1969
1970         /**
1971          * Get an associative array for selecting this title from
1972          * the "cur" table
1973          *
1974          * @return array
1975          * @access public
1976          */
1977         function curCond() {
1978                 wfDebugDieBacktrace( 'curCond called' );
1979                 return array( 'cur_namespace' => $this->mNamespace, 'cur_title' => $this->mDbkeyform );
1980         }
1981
1982         /**
1983          * Get an associative array for selecting this title from the
1984          * "old" table
1985          *
1986          * @return array
1987          * @access public
1988          */
1989         function oldCond() {
1990                 wfDebugDieBacktrace( 'oldCond called' );
1991                 return array( 'old_namespace' => $this->mNamespace, 'old_title' => $this->mDbkeyform );
1992         }
1993
1994         /**
1995          * Get the revision ID of the previous revision
1996          *
1997          * @param integer $revision  Revision ID. Get the revision that was before this one.
1998          * @return interger $oldrevision|false
1999          */
2000         function getPreviousRevisionID( $revision ) {
2001                 $dbr =& wfGetDB( DB_SLAVE );
2002                 return $dbr->selectField( 'revision', 'rev_id',
2003                         'rev_page=' . IntVal( $this->getArticleId() ) .
2004                         ' AND rev_id<' . IntVal( $revision ) . ' ORDER BY rev_id DESC' );
2005         }
2006
2007         /**
2008          * Get the revision ID of the next revision
2009          *
2010          * @param integer $revision  Revision ID. Get the revision that was after this one.
2011          * @return interger $oldrevision|false
2012          */
2013         function getNextRevisionID( $revision ) {
2014                 $dbr =& wfGetDB( DB_SLAVE );
2015                 return $dbr->selectField( 'revision', 'rev_id',
2016                         'rev_page=' . IntVal( $this->getArticleId() ) .
2017                         ' AND rev_id>' . IntVal( $revision ) . ' ORDER BY rev_id' );
2018         }
2019
2020         /**
2021          * Compare with another title.
2022          *
2023          * @param Title $title
2024          * @return bool
2025          */
2026         function equals( &$title ) {
2027                 return $this->getInterwiki() == $title->getInterwiki()
2028                         && $this->getNamespace() == $title->getNamespace()
2029                         && $this->getDbkey() == $title->getDbkey();
2030         }
2031
2032         /**
2033          * Check if page exists
2034          * @return bool
2035          */
2036         function exists() {
2037                 return $this->getArticleId() != 0;
2038         }
2039
2040         /**
2041          * Should a link should be displayed as a known link, just based on its title?
2042          *
2043          * Currently, a self-link with a fragment, special pages and image pages are in
2044          * this category. Special pages never exist in the database. Some images do not
2045          * have description pages in the database, but the description page contains
2046          * useful history information that the user may want to link to.
2047          */
2048         function isAlwaysKnown() {
2049                 return  $this->isExternal() || ( 0 == $this->mNamespace && "" == $this->mDbkeyform )
2050                   || NS_SPECIAL == $this->mNamespace || NS_IMAGE == $this->mNamespace;
2051         }
2052
2053         /**
2054          * Update page_touched timestamps on pages linking to this title.
2055          * In principal, this could be backgrounded and could also do squid
2056          * purging.
2057          */
2058         function touchLinks() {
2059                 $fname = 'Title::touchLinks';
2060
2061                 $dbw =& wfGetDB( DB_MASTER );
2062
2063                 $res = $dbw->select( 'pagelinks',
2064                         array( 'pl_from' ),
2065                         array(
2066                                 'pl_namespace' => $this->getNamespace(),
2067                                 'pl_title'     => $this->getDbKey() ),
2068                         $fname );
2069                 if ( 0 == $dbw->numRows( $res ) ) {
2070                         return;
2071                 }
2072
2073                 $arr = array();
2074                 $toucharr = array();
2075                 while( $row = $dbw->fetchObject( $res ) ) {
2076                         $toucharr[] = $row->pl_from;
2077                 }
2078
2079                 $dbw->update( 'page', /* SET */ array( 'page_touched' => $dbw->timestamp() ),
2080                                                         /* WHERE */ array( 'page_id' => $toucharr ),$fname);
2081         }
2082 }
2083 ?>