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 $wgTitleCache = array();
  13
  14 define ( 'GAID_FOR_UPDATE', 1 );
  15
  16 # Title::newFromTitle maintains a cache to avoid
  17 # expensive re-normalization of commonly used titles.
  18 # On a batch operation this can become a memory leak
  19 # if not bounded. After hitting this many titles,
  20 # reset the cache.
  21 define( 'MW_TITLECACHE_MAX', 1000 );
  22
  23 /**
  24  * Title class
  25  * - Represents a title, which may contain an interwiki designation or namespace
  26  * - Can fetch various kinds of data from the database, albeit inefficiently.
  27  *
  28  * @package MediaWiki
  29  */
  30 class Title {
  31         /**
  32          * All member variables should be considered private
  33          * Please use the accessor functions
  34          */
  35
  36          /**#@+
  37          * @access private
  38          */
  39
  40         var $mTextform;           # Text form (spaces not underscores) of the main part
  41         var $mUrlform;            # URL-encoded form of the main part
  42         var $mDbkeyform;          # Main part with underscores
  43         var $mNamespace;          # Namespace index, i.e. one of the NS_xxxx constants
  44         var $mInterwiki;          # Interwiki prefix (or null string)
  45         var $mFragment;           # Title fragment (i.e. the bit after the #)
  46         var $mArticleID;          # Article ID, fetched from the link cache on demand
  47         var $mLatestID;         # ID of most recent revision
  48         var $mRestrictions;       # Array of groups allowed to edit this article
  49                               # Only null or "sysop" are supported
  50         var $mRestrictionsLoaded; # Boolean for initialisation on demand
  51         var $mPrefixedText;       # Text form including namespace/interwiki, initialised on demand
  52         var $mDefaultNamespace;   # Namespace index when there is no namespace
  53                               # Zero except in {{transclusion}} tags
  54         var $mWatched;            # Is $wgUser watching this page? NULL if unfilled, accessed through userIsWatching()
  55         /**#@-*/
  56
  57
  58         /**
  59          * Constructor
  60          * @access private
  61          */
  62         /* private */ function Title() {
  63                 $this->mInterwiki = $this->mUrlform =
  64                 $this->mTextform = $this->mDbkeyform = '';
  65                 $this->mArticleID = -1;
  66                 $this->mNamespace = NS_MAIN;
  67                 $this->mRestrictionsLoaded = false;
  68                 $this->mRestrictions = array();
  69                 # Dont change the following, NS_MAIN is hardcoded in several place
  70                 # See bug #696
  71                 $this->mDefaultNamespace = NS_MAIN;
  72                 $this->mWatched = NULL;
  73                 $this->mLatestID = false;
  74         }
  75
  76         /**
  77          * Create a new Title from a prefixed DB key
  78          * @param string $key The database key, which has underscores
  79          *      instead of spaces, possibly including namespace and
  80          *      interwiki prefixes
  81          * @return Title the new object, or NULL on an error
  82          * @static
  83          * @access public
  84          */
  85         /* static */ function newFromDBkey( $key ) {
  86                 $t = new Title();
  87                 $t->mDbkeyform = $key;
  88                 if( $t->secureAndSplit() )
  89                         return $t;
  90                 else
  91                         return NULL;
  92         }
  93
  94         /**
  95          * Create a new Title from text, such as what one would
  96          * find in a link. Decodes any HTML entities in the text.
  97          *
  98          * @param string $text the link text; spaces, prefixes,
  99          *      and an initial ':' indicating the main namespace
 100          *      are accepted
 101          * @param int $defaultNamespace the namespace to use if
 102          *      none is specified by a prefix
 103          * @return Title the new object, or NULL on an error
 104          * @static
 105          * @access public
 106          */
 107         function newFromText( $text, $defaultNamespace = NS_MAIN ) {
 108                 global $wgTitleCache;
 109                 $fname = 'Title::newFromText';
 110                 wfProfileIn( $fname );
 111
 112                 if( is_object( $text ) ) {
 113                         wfDebugDieBacktrace( 'Title::newFromText given an object' );
 114                 }
 115
 116                 /**
 117                  * Wiki pages often contain multiple links to the same page.
 118                  * Title normalization and parsing can become expensive on
 119                  * pages with many links, so we can save a little time by
 120                  * caching them.
 121                  *
 122                  * In theory these are value objects and won't get changed...
 123                  */
 124                 if( $defaultNamespace == NS_MAIN && isset( $wgTitleCache[$text] ) ) {
 125                         wfProfileOut( $fname );
 126                         return $wgTitleCache[$text];
 127                 }
 128
 129                 /**
 130                  * Convert things like &eacute; &#257; or &#x3017; into real text...
 131                  */
 132                 $filteredText = Sanitizer::decodeCharReferences( $text );
 133
 134                 $t =& new Title();
 135                 $t->mDbkeyform = str_replace( ' ', '_', $filteredText );
 136                 $t->mDefaultNamespace = $defaultNamespace;
 137
 138                 static $cachedcount = 0 ;
 139                 if( $t->secureAndSplit() ) {
 140                         if( $defaultNamespace == NS_MAIN ) {
 141                                 if( $cachedcount >= MW_TITLECACHE_MAX ) {
 142                                         # Avoid memory leaks on mass operations...
 143                                         $wgTitleCache = array();
 144                                         $cachedcount=0;
 145                                 }
 146                                 $cachedcount++;
 147                                 $wgTitleCache[$text] =& $t;
 148                         }
 149                         wfProfileOut( $fname );
 150                         return $t;
 151                 } else {
 152                         wfProfileOut( $fname );
 153                         $ret = NULL;
 154                         return $ret;
 155                 }
 156         }
 157
 158         /**
 159          * Create a new Title from URL-encoded text. Ensures that
 160          * the given title's length does not exceed the maximum.
 161          * @param string $url the title, as might be taken from a URL
 162          * @return Title the new object, or NULL on an error
 163          * @static
 164          * @access public
 165          */
 166         function newFromURL( $url ) {
 167                 global $wgLegalTitleChars;
 168                 $t = new Title();
 169
 170                 # For compatibility with old buggy URLs. "+" is usually not valid in titles,
 171                 # but some URLs used it as a space replacement and they still come
 172                 # from some external search tools.
 173                 if ( strpos( $wgLegalTitleChars, '+' ) === false ) {
 174                         $url = str_replace( '+', ' ', $url );
 175                 }
 176
 177                 $t->mDbkeyform = str_replace( ' ', '_', $url );
 178                 if( $t->secureAndSplit() ) {
 179                         return $t;
 180                 } else {
 181                         return NULL;
 182                 }
 183         }
 184
 185         /**
 186          * Create a new Title from an article ID
 187          *
 188          * @todo This is inefficiently implemented, the page row is requested
 189          *       but not used for anything else
 190          *
 191          * @param int $id the page_id corresponding to the Title to create
 192          * @return Title the new object, or NULL on an error
 193          * @access public
 194          * @static
 195          */
 196         function newFromID( $id ) {
 197                 $fname = 'Title::newFromID';
 198                 $dbr =& wfGetDB( DB_SLAVE );
 199                 $row = $dbr->selectRow( 'page', array( 'page_namespace', 'page_title' ),
 200                         array( 'page_id' => $id ), $fname );
 201                 if ( $row !== false ) {
 202                         $title = Title::makeTitle( $row->page_namespace, $row->page_title );
 203                 } else {
 204                         $title = NULL;
 205                 }
 206                 return $title;
 207         }
 208
 209         /**
 210          * Create a new Title from a namespace index and a DB key.
 211          * It's assumed that $ns and $title are *valid*, for instance when
 212          * they came directly from the database or a special page name.
 213          * For convenience, spaces are converted to underscores so that
 214          * eg user_text fields can be used directly.
 215          *
 216          * @param int $ns the namespace of the article
 217          * @param string $title the unprefixed database key form
 218          * @return Title the new object
 219          * @static
 220          * @access public
 221          */
 222         function &makeTitle( $ns, $title ) {
 223                 $t =& new Title();
 224                 $t->mInterwiki = '';
 225                 $t->mFragment = '';
 226                 $t->mNamespace = intval( $ns );
 227                 $t->mDbkeyform = str_replace( ' ', '_', $title );
 228                 $t->mArticleID = ( $ns >= 0 ) ? -1 : 0;
 229                 $t->mUrlform = wfUrlencode( $t->mDbkeyform );
 230                 $t->mTextform = str_replace( '_', ' ', $title );
 231                 return $t;
 232         }
 233
 234         /**
 235          * Create a new Title frrom a namespace index and a DB key.
 236          * The parameters will be checked for validity, which is a bit slower
 237          * than makeTitle() but safer for user-provided data.
 238          *
 239          * @param int $ns the namespace of the article
 240          * @param string $title the database key form
 241          * @return Title the new object, or NULL on an error
 242          * @static
 243          * @access public
 244          */
 245         function makeTitleSafe( $ns, $title ) {
 246                 $t = new Title();
 247                 $t->mDbkeyform = Title::makeName( $ns, $title );
 248                 if( $t->secureAndSplit() ) {
 249                         return $t;
 250                 } else {
 251                         return NULL;
 252                 }
 253         }
 254
 255         /**
 256          * Create a new Title for the Main Page
 257          *
 258          * @static
 259          * @return Title the new object
 260          * @access public
 261          */
 262         function newMainPage() {
 263                 return Title::newFromText( wfMsgForContent( 'mainpage' ) );
 264         }
 265
 266         /**
 267          * Create a new Title for a redirect
 268          * @param string $text the redirect title text
 269          * @return Title the new object, or NULL if the text is not a
 270          *      valid redirect
 271          * @static
 272          * @access public
 273          */
 274         function newFromRedirect( $text ) {
 275                 global $wgMwRedir;
 276                 $rt = NULL;
 277                 if ( $wgMwRedir->matchStart( $text ) ) {
 278                         if ( preg_match( '/\[{2}(.*?)(?:\||\]{2})/', $text, $m ) ) {
 279                                 # categories are escaped using : for example one can enter:
 280                                 # #REDIRECT [[:Category:Music]]. Need to remove it.
 281                                 if ( substr($m[1],0,1) == ':') {
 282                                         # We don't want to keep the ':'
 283                                         $m[1] = substr( $m[1], 1 );
 284                                 }
 285
 286                                 $rt = Title::newFromText( $m[1] );
 287                                 # Disallow redirects to Special:Userlogout
 288                                 if ( !is_null($rt) && $rt->getNamespace() == NS_SPECIAL && preg_match( '/^Userlogout/i', $rt->getText() ) ) {
 289                                         $rt = NULL;
 290                                 }
 291                         }
 292                 }
 293                 return $rt;
 294         }
 295
 296 #----------------------------------------------------------------------------
 297 #       Static functions
 298 #----------------------------------------------------------------------------
 299
 300         /**
 301          * Get the prefixed DB key associated with an ID
 302          * @param int $id the page_id of the article
 303          * @return Title an object representing the article, or NULL
 304          *      if no such article was found
 305          * @static
 306          * @access public
 307          */
 308         function nameOf( $id ) {
 309                 $fname = 'Title::nameOf';
 310                 $dbr =& wfGetDB( DB_SLAVE );
 311
 312                 $s = $dbr->selectRow( 'page', array( 'page_namespace','page_title' ),  array( 'page_id' => $id ), $fname );
 313                 if ( $s === false ) { return NULL; }
 314
 315                 $n = Title::makeName( $s->page_namespace, $s->page_title );
 316                 return $n;
 317         }
 318
 319         /**
 320          * Get a regex character class describing the legal characters in a link
 321          * @return string the list of characters, not delimited
 322          * @static
 323          * @access public
 324          */
 325         function legalChars() {
 326                 global $wgLegalTitleChars;
 327                 return $wgLegalTitleChars;
 328         }
 329
 330         /**
 331          * Get a string representation of a title suitable for
 332          * including in a search index
 333          *
 334          * @param int $ns a namespace index
 335          * @param string $title text-form main part
 336          * @return string a stripped-down title string ready for the
 337          *      search index
 338          */
 339         /* static */ function indexTitle( $ns, $title ) {
 340                 global $wgContLang;
 341                 require_once( 'SearchEngine.php' );
 342
 343                 $lc = SearchEngine::legalSearchChars() . '&#;';
 344                 $t = $wgContLang->stripForSearch( $title );
 345                 $t = preg_replace( "/[^{$lc}]+/", ' ', $t );
 346                 $t = strtolower( $t );
 347
 348                 # Handle 's, s'
 349                 $t = preg_replace( "/([{$lc}]+)'s( |$)/", "\\1 \\1's ", $t );
 350                 $t = preg_replace( "/([{$lc}]+)s'( |$)/", "\\1s ", $t );
 351
 352                 $t = preg_replace( "/\\s+/", ' ', $t );
 353
 354                 if ( $ns == NS_IMAGE ) {
 355                         $t = preg_replace( "/ (png|gif|jpg|jpeg|ogg)$/", "", $t );
 356                 }
 357                 return trim( $t );
 358         }
 359
 360         /*
 361          * Make a prefixed DB key from a DB key and a namespace index
 362          * @param int $ns numerical representation of the namespace
 363          * @param string $title the DB key form the title
 364          * @return string the prefixed form of the title
 365          */
 366         /* static */ function makeName( $ns, $title ) {
 367                 global $wgContLang;
 368
 369                 $n = $wgContLang->getNsText( $ns );
 370                 return $n == '' ? $title : "$n:$title";
 371         }
 372
 373         /**
 374          * Returns the URL associated with an interwiki prefix
 375          * @param string $key the interwiki prefix (e.g. "MeatBall")
 376          * @return the associated URL, containing "$1", which should be
 377          *      replaced by an article title
 378          * @static (arguably)
 379          * @access public
 380          */
 381         function getInterwikiLink( $key )  {
 382                 global $wgMemc, $wgDBname, $wgInterwikiExpiry, $wgTitleInterwikiCache;
 383                 global $wgInterwikiCache;
 384                 $fname = 'Title::getInterwikiLink';
 385
 386                 wfProfileIn( $fname );
 387
 388                 $key = strtolower( $key );
 389
 390                 $k = $wgDBname.':interwiki:'.$key;
 391                 if( array_key_exists( $k, $wgTitleInterwikiCache ) ) {
 392                         wfProfileOut( $fname );
 393                         return $wgTitleInterwikiCache[$k]->iw_url;
 394                 }
 395
 396                 if ($wgInterwikiCache) {
 397                         wfProfileOut( $fname );
 398                         return $this->getInterwikiCached( $key );
 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          * Fetch interwiki prefix data from local cache in constant database
 435          *
 436          * More logic is explained in DefaultSettings
 437          *
 438          * @return string URL of interwiki site
 439          * @access public
 440          */
 441         function getInterwikiCached( $key ) {
 442                 global $wgDBname, $wgInterwikiCache, $wgInterwikiScopes, $wgInterwikiFallbackSite;
 443                 global $wgTitleInterwikiCache;
 444                 static $db, $site;
 445                 if (!db)
 446                         $db=dba_open($wgInterwikiCache,'r','cdb');
 447                 /* Resolve site name */
 448                 if ($wgInterwikiScopes>=3 and !$site) {
 449                         $site = dba_fetch("__sites:{$wgDBname}", $db);
 450                         if ($site=="")
 451                                 $site = $wgInterwikiFallbackSite;
 452                 }
 453                 $value = dba_fetch("{$wgDBname}:{$key}", $db);
 454                 if ($value=='' and $wgInterwikiScopes>=3) {
 455                         /* try site-level */
 456                         $value = dba_fetch("_{$site}:{$key}", $db);
 457                 }
 458                 if ($value=='' and $wgInterwikiScopes>=2) {
 459                         /* try globals */
 460                         $value = dba_fetch("__globals:{$key}", $db);
 461                 }
 462                 if ($value=='undef')
 463                         $value='';
 464                 $s = (object)false;
 465                 $s->iw_url = '';
 466                 $s->iw_local = 0;
 467                 $s->iw_trans = 0;
 468                 if ($value!='') {
 469                         list($local,$url)=explode(' ',$value,2);
 470                         $s->iw_url=$url;
 471                         $s->iw_local=$local;
 472                 }
 473                 $wgTitleInterwikiCache[$wgDBname.':interwiki:'.$key] = $s;
 474                 return $s->iw_url;
 475         }
 476         /**
 477          * Determine whether the object refers to a page within
 478          * this project.
 479          *
 480          * @return bool TRUE if this is an in-project interwiki link
 481          *      or a wikilink, FALSE otherwise
 482          * @access public
 483          */
 484         function isLocal() {
 485                 global $wgTitleInterwikiCache, $wgDBname;
 486
 487                 if ( $this->mInterwiki != '' ) {
 488                         # Make sure key is loaded into cache
 489                         $this->getInterwikiLink( $this->mInterwiki );
 490                         $k = $wgDBname.':interwiki:' . $this->mInterwiki;
 491                         return (bool)($wgTitleInterwikiCache[$k]->iw_local);
 492                 } else {
 493                         return true;
 494                 }
 495         }
 496
 497         /**
 498          * Determine whether the object refers to a page within
 499          * this project and is transcludable.
 500          *
 501          * @return bool TRUE if this is transcludable
 502          * @access public
 503          */
 504         function isTrans() {
 505                 global $wgTitleInterwikiCache, $wgDBname;
 506
 507                 if ($this->mInterwiki == '' || !$this->isLocal())
 508                         return false;
 509                 # Make sure key is loaded into cache
 510                 $this->getInterwikiLink( $this->mInterwiki );
 511                 $k = $wgDBname.':interwiki:' . $this->mInterwiki;
 512                 return (bool)($wgTitleInterwikiCache[$k]->iw_trans);
 513         }
 514
 515         /**
 516          * Update the page_touched field for an array of title objects
 517          * @todo Inefficient unless the IDs are already loaded into the
 518          *      link cache
 519          * @param array $titles an array of Title objects to be touched
 520          * @param string $timestamp the timestamp to use instead of the
 521          *      default current time
 522          * @static
 523          * @access public
 524          */
 525         function touchArray( $titles, $timestamp = '' ) {
 526
 527                 if ( count( $titles ) == 0 ) {
 528                         return;
 529                 }
 530                 $dbw =& wfGetDB( DB_MASTER );
 531                 if ( $timestamp == '' ) {
 532                         $timestamp = $dbw->timestamp();
 533                 }
 534                 /*
 535                 $page = $dbw->tableName( 'page' );
 536                 $sql = "UPDATE $page SET page_touched='{$timestamp}' WHERE page_id IN (";
 537                 $first = true;
 538
 539                 foreach ( $titles as $title ) {
 540                         if ( $wgUseFileCache ) {
 541                                 $cm = new CacheManager($title);
 542                                 @unlink($cm->fileCacheName());
 543                         }
 544
 545                         if ( ! $first ) {
 546                                 $sql .= ',';
 547                         }
 548                         $first = false;
 549                         $sql .= $title->getArticleID();
 550                 }
 551                 $sql .= ')';
 552                 if ( ! $first ) {
 553                         $dbw->query( $sql, 'Title::touchArray' );
 554                 }
 555                 */
 556                 // hack hack hack -- brion 2005-07-11. this was unfriendly to db.
 557                 // do them in small chunks:
 558                 $fname = 'Title::touchArray';
 559                 foreach( $titles as $title ) {
 560                         $dbw->update( 'page',
 561                                 array( 'page_touched' => $timestamp ),
 562                                 array(
 563                                         'page_namespace' => $title->getNamespace(),
 564                                         'page_title'     => $title->getDBkey() ),
 565                                 $fname );
 566                 }
 567         }
 568
 569 #----------------------------------------------------------------------------
 570 #       Other stuff
 571 #----------------------------------------------------------------------------
 572
 573         /** Simple accessors */
 574         /**
 575          * Get the text form (spaces not underscores) of the main part
 576          * @return string
 577          * @access public
 578          */
 579         function getText() { return $this->mTextform; }
 580         /**
 581          * Get the URL-encoded form of the main part
 582          * @return string
 583          * @access public
 584          */
 585         function getPartialURL() { return $this->mUrlform; }
 586         /**
 587          * Get the main part with underscores
 588          * @return string
 589          * @access public
 590          */
 591         function getDBkey() { return $this->mDbkeyform; }
 592         /**
 593          * Get the namespace index, i.e. one of the NS_xxxx constants
 594          * @return int
 595          * @access public
 596          */
 597         function getNamespace() { return $this->mNamespace; }
 598         /**
 599          * Get the namespace text
 600          * @return string
 601          * @access public
 602          */
 603         function getNsText() {
 604                 global $wgContLang;
 605                 return $wgContLang->getNsText( $this->mNamespace );
 606         }
 607         /**
 608          * Get the namespace text of the subject (rather than talk) page
 609          * @return string
 610          * @access public
 611          */
 612         function getSubjectNsText() {
 613                 global $wgContLang;
 614                 return $wgContLang->getNsText( Namespace::getSubject( $this->mNamespace ) );
 615         }
 616
 617         /**
 618          * Get the interwiki prefix (or null string)
 619          * @return string
 620          * @access public
 621          */
 622         function getInterwiki() { return $this->mInterwiki; }
 623         /**
 624          * Get the Title fragment (i.e. the bit after the #)
 625          * @return string
 626          * @access public
 627          */
 628         function getFragment() { return $this->mFragment; }
 629         /**
 630          * Get the default namespace index, for when there is no namespace
 631          * @return int
 632          * @access public
 633          */
 634         function getDefaultNamespace() { return $this->mDefaultNamespace; }
 635
 636         /**
 637          * Get title for search index
 638          * @return string a stripped-down title string ready for the
 639          *      search index
 640          */
 641         function getIndexTitle() {
 642                 return Title::indexTitle( $this->mNamespace, $this->mTextform );
 643         }
 644
 645         /**
 646          * Get the prefixed database key form
 647          * @return string the prefixed title, with underscores and
 648          *      any interwiki and namespace prefixes
 649          * @access public
 650          */
 651         function getPrefixedDBkey() {
 652                 $s = $this->prefix( $this->mDbkeyform );
 653                 $s = str_replace( ' ', '_', $s );
 654                 return $s;
 655         }
 656
 657         /**
 658          * Get the prefixed title with spaces.
 659          * This is the form usually used for display
 660          * @return string the prefixed title, with spaces
 661          * @access public
 662          */
 663         function getPrefixedText() {
 664                 global $wgContLang;
 665                 if ( empty( $this->mPrefixedText ) ) { // FIXME: bad usage of empty() ?
 666                         $s = $this->prefix( $this->mTextform );
 667                         $s = str_replace( '_', ' ', $s );
 668                         $this->mPrefixedText = $s;
 669                 }
 670                 return $this->mPrefixedText;
 671         }
 672
 673         /**
 674          * Get the prefixed title with spaces, plus any fragment
 675          * (part beginning with '#')
 676          * @return string the prefixed title, with spaces and
 677          *      the fragment, including '#'
 678          * @access public
 679          */
 680         function getFullText() {
 681                 global $wgContLang;
 682                 $text = $this->getPrefixedText();
 683                 if( '' != $this->mFragment ) {
 684                         $text .= '#' . $this->mFragment;
 685                 }
 686                 return $text;
 687         }
 688
 689         /**
 690          * Get a URL-encoded title (not an actual URL) including interwiki
 691          * @return string the URL-encoded form
 692          * @access public
 693          */
 694         function getPrefixedURL() {
 695                 $s = $this->prefix( $this->mDbkeyform );
 696                 $s = str_replace( ' ', '_', $s );
 697
 698                 $s = wfUrlencode ( $s ) ;
 699
 700                 # Cleaning up URL to make it look nice -- is this safe?
 701                 $s = str_replace( '%28', '(', $s );
 702                 $s = str_replace( '%29', ')', $s );
 703
 704                 return $s;
 705         }
 706
 707         /**
 708          * Get a real URL referring to this title, with interwiki link and
 709          * fragment
 710          *
 711          * @param string $query an optional query string, not used
 712          *      for interwiki links
 713          * @return string the URL
 714          * @access public
 715          */
 716         function getFullURL( $query = '' ) {
 717                 global $wgContLang, $wgServer, $wgRequest;
 718
 719                 if ( '' == $this->mInterwiki ) {
 720                         $url = $this->getLocalUrl( $query );
 721
 722                         // Ugly quick hack to avoid duplicate prefixes (bug 4571 etc)
 723                         // Correct fix would be to move the prepending elsewhere.
 724                         if ($wgRequest->getVal('action') != 'render') {
 725                                 $url = $wgServer . $url;
 726                         }
 727                 } else {
 728                         $baseUrl = $this->getInterwikiLink( $this->mInterwiki );
 729
 730                         $namespace = $wgContLang->getNsText( $this->mNamespace );
 731                         if ( '' != $namespace ) {
 732                                 # Can this actually happen? Interwikis shouldn't be parsed.
 733                                 $namespace .= ':';
 734                         }
 735                         $url = str_replace( '$1', $namespace . $this->mUrlform, $baseUrl );
 736                         if( $query != '' ) {
 737                                 if( false === strpos( $url, '?' ) ) {
 738                                         $url .= '?';
 739                                 } else {
 740                                         $url .= '&';
 741                                 }
 742                                 $url .= $query;
 743                         }
 744                         if ( '' != $this->mFragment ) {
 745                                 $url .= '#' . $this->mFragment;
 746                         }
 747                 }
 748                 wfRunHooks( 'GetFullURL', array( &$this, &$url, $query ) );
 749                 return $url;
 750         }
 751
 752         /**
 753          * Get a URL with no fragment or server name.  If this page is generated
 754          * with action=render, $wgServer is prepended.
 755          * @param string $query an optional query string; if not specified,
 756          *      $wgArticlePath will be used.
 757          * @return string the URL
 758          * @access public
 759          */
 760         function getLocalURL( $query = '' ) {
 761                 global $wgArticlePath, $wgScript, $wgServer, $wgRequest;
 762
 763                 if ( $this->isExternal() ) {
 764                         $url = $this->getFullURL();
 765                 } else {
 766                         $dbkey = wfUrlencode( $this->getPrefixedDBkey() );
 767                         if ( $query == '' ) {
 768                                 $url = str_replace( '$1', $dbkey, $wgArticlePath );
 769                         } else {
 770                                 global $wgActionPaths;
 771                                 $url = false;
 772                                 if( !empty( $wgActionPaths ) &&
 773                                         preg_match( '/^(.*&|)action=([^&]*)(&(.*)|)$/', $query, $matches ) )
 774                                 {
 775                                         $action = urldecode( $matches[2] );
 776                                         if( isset( $wgActionPaths[$action] ) ) {
 777                                                 $query = $matches[1];
 778                                                 if( isset( $matches[4] ) ) $query .= $matches[4];
 779                                                 $url = str_replace( '$1', $dbkey, $wgActionPaths[$action] );
 780                                                 if( $query != '' ) $url .= '?' . $query;
 781                                         }
 782                                 }
 783                                 if ( $url === false ) {
 784                                         if ( $query == '-' ) {
 785                                                 $query = '';
 786                                         }
 787                                         $url = "{$wgScript}?title={$dbkey}&{$query}";
 788                                 }
 789                         }
 790
 791                         // FIXME: this causes breakage in various places when we
 792                         // actually expected a local URL and end up with dupe prefixes.
 793                         if ($wgRequest->getVal('action') == 'render') {
 794                                 $url = $wgServer . $url;
 795                         }
 796                 }
 797                 wfRunHooks( 'GetLocalURL', array( &$this, &$url, $query ) );
 798                 return $url;
 799         }
 800
 801         /**
 802          * Get an HTML-escaped version of the URL form, suitable for
 803          * using in a link, without a server name or fragment
 804          * @param string $query an optional query string
 805          * @return string the URL
 806          * @access public
 807          */
 808         function escapeLocalURL( $query = '' ) {
 809                 return htmlspecialchars( $this->getLocalURL( $query ) );
 810         }
 811
 812         /**
 813          * Get an HTML-escaped version of the URL form, suitable for
 814          * using in a link, including the server name and fragment
 815          *
 816          * @return string the URL
 817          * @param string $query an optional query string
 818          * @access public
 819          */
 820         function escapeFullURL( $query = '' ) {
 821                 return htmlspecialchars( $this->getFullURL( $query ) );
 822         }
 823
 824         /**
 825          * Get the URL form for an internal link.
 826          * - Used in various Squid-related code, in case we have a different
 827          * internal hostname for the server from the exposed one.
 828          *
 829          * @param string $query an optional query string
 830          * @return string the URL
 831          * @access public
 832          */
 833         function getInternalURL( $query = '' ) {
 834                 global $wgInternalServer;
 835                 $url = $wgInternalServer . $this->getLocalURL( $query );
 836                 wfRunHooks( 'GetInternalURL', array( &$this, &$url, $query ) );
 837                 return $url;
 838         }
 839
 840         /**
 841          * Get the edit URL for this Title
 842          * @return string the URL, or a null string if this is an
 843          *      interwiki link
 844          * @access public
 845          */
 846         function getEditURL() {
 847                 global $wgServer, $wgScript;
 848
 849                 if ( '' != $this->mInterwiki ) { return ''; }
 850                 $s = $this->getLocalURL( 'action=edit' );
 851
 852                 return $s;
 853         }
 854
 855         /**
 856          * Get the HTML-escaped displayable text form.
 857          * Used for the title field in <a> tags.
 858          * @return string the text, including any prefixes
 859          * @access public
 860          */
 861         function getEscapedText() {
 862                 return htmlspecialchars( $this->getPrefixedText() );
 863         }
 864
 865         /**
 866          * Is this Title interwiki?
 867          * @return boolean
 868          * @access public
 869          */
 870         function isExternal() { return ( '' != $this->mInterwiki ); }
 871
 872         /**
 873          * Does the title correspond to a protected article?
 874          * @param string $what the action the page is protected from,
 875          *      by default checks move and edit
 876          * @return boolean
 877          * @access public
 878          */
 879         function isProtected( $action = '' ) {
 880                 global $wgRestrictionLevels;
 881                 if ( -1 == $this->mNamespace ) { return true; }
 882
 883                 if( $action == 'edit' || $action == '' ) {
 884                         $r = $this->getRestrictions( 'edit' );
 885                         foreach( $wgRestrictionLevels as $level ) {
 886                                 if( in_array( $level, $r ) && $level != '' ) {
 887                                         return( true );
 888                                 }
 889                         }
 890                 }
 891
 892                 if( $action == 'move' || $action == '' ) {
 893                         $r = $this->getRestrictions( 'move' );
 894                         foreach( $wgRestrictionLevels as $level ) {
 895                                 if( in_array( $level, $r ) && $level != '' ) {
 896                                         return( true );
 897                                 }
 898                         }
 899                 }
 900
 901                 return false;
 902         }
 903
 904         /**
 905          * Is $wgUser is watching this page?
 906          * @return boolean
 907          * @access public
 908          */
 909         function userIsWatching() {
 910                 global $wgUser;
 911
 912                 if ( is_null( $this->mWatched ) ) {
 913                         if ( -1 == $this->mNamespace || 0 == $wgUser->getID()) {
 914                                 $this->mWatched = false;
 915                         } else {
 916                                 $this->mWatched = $wgUser->isWatched( $this );
 917                         }
 918                 }
 919                 return $this->mWatched;
 920         }
 921
 922         /**
 923          * Can $wgUser perform $action this page?
 924          * @param string $action action that permission needs to be checked for
 925          * @return boolean
 926          * @access private
 927          */
 928         function userCan($action) {
 929                 $fname = 'Title::userCan';
 930                 wfProfileIn( $fname );
 931
 932                 global $wgUser;
 933                 if( NS_SPECIAL == $this->mNamespace ) {
 934                         wfProfileOut( $fname );
 935                         return false;
 936                 }
 937                 // XXX: This is the code that prevents unprotecting a page in NS_MEDIAWIKI
 938                 // from taking effect -ævar
 939                 if( NS_MEDIAWIKI == $this->mNamespace &&
 940                     !$wgUser->isAllowed('editinterface') ) {
 941                         wfProfileOut( $fname );
 942                         return false;
 943                 }
 944
 945                 if( $this->mDbkeyform == '_' ) {
 946                         # FIXME: Is this necessary? Shouldn't be allowed anyway...
 947                         wfProfileOut( $fname );
 948                         return false;
 949                 }
 950
 951                 # protect global styles and js
 952                 if ( NS_MEDIAWIKI == $this->mNamespace
 953                  && preg_match("/\\.(css|js)$/", $this->mTextform )
 954                      && !$wgUser->isAllowed('editinterface') ) {
 955                         wfProfileOut( $fname );
 956                         return false;
 957                 }
 958
 959                 # protect css/js subpages of user pages
 960                 # XXX: this might be better using restrictions
 961                 # XXX: Find a way to work around the php bug that prevents using $this->userCanEditCssJsSubpage() from working
 962                 if( NS_USER == $this->mNamespace
 963                         && preg_match("/\\.(css|js)$/", $this->mTextform )
 964                         && !$wgUser->isAllowed('editinterface')
 965                         && !preg_match('/^'.preg_quote($wgUser->getName(), '/').'\//', $this->mTextform) ) {
 966                         wfProfileOut( $fname );
 967                         return false;
 968                 }
 969
 970                 foreach( $this->getRestrictions($action) as $right ) {
 971                         // Backwards compatibility, rewrite sysop -> protect
 972                         if ( $right == 'sysop' ) {
 973                                 $right = 'protect';
 974                         }
 975                         if( '' != $right && !$wgUser->isAllowed( $right ) ) {
 976                                 wfProfileOut( $fname );
 977                                 return false;
 978                         }
 979                 }
 980
 981                 if( $action == 'move' &&
 982                         !( $this->isMovable() && $wgUser->isAllowed( 'move' ) ) ) {
 983                         wfProfileOut( $fname );
 984                         return false;
 985                 }
 986
 987                 if( $action == 'create' ) {
 988                         if( (  $this->isTalkPage() && !$wgUser->isAllowed( 'createtalk' ) ) ||
 989                                 ( !$this->isTalkPage() && !$wgUser->isAllowed( 'createpage' ) ) ) {
 990                                 return false;
 991                         }
 992                 }
 993
 994                 wfProfileOut( $fname );
 995                 return true;
 996         }
 997
 998         /**
 999          * Can $wgUser edit this page?
1000          * @return boolean
1001          * @access public
1002          */
1003         function userCanEdit() {
1004                 return $this->userCan('edit');
1005         }
1006
1007         /**
1008          * Can $wgUser move this page?
1009          * @return boolean
1010          * @access public
1011          */
1012         function userCanMove() {
1013                 return $this->userCan('move');
1014         }
1015
1016         /**
1017          * Would anybody with sufficient privileges be able to move this page?
1018          * Some pages just aren't movable.
1019          *
1020          * @return boolean
1021          * @access public
1022          */
1023         function isMovable() {
1024                 return Namespace::isMovable( $this->getNamespace() )
1025                         && $this->getInterwiki() == '';
1026         }
1027
1028         /**
1029          * Can $wgUser read this page?
1030          * @return boolean
1031          * @access public
1032          */
1033         function userCanRead() {
1034                 global $wgUser;
1035
1036                 if( $wgUser->isAllowed('read') ) {
1037                         return true;
1038                 } else {
1039                         global $wgWhitelistRead;
1040
1041                         /** If anon users can create an account,
1042                             they need to reach the login page first! */
1043                         if( $wgUser->isAllowed( 'createaccount' )
1044                             && $this->getNamespace() == NS_SPECIAL
1045                             && $this->getText() == 'Userlogin' ) {
1046                                 return true;
1047                         }
1048
1049                         /** some pages are explicitly allowed */
1050                         $name = $this->getPrefixedText();
1051                         if( $wgWhitelistRead && in_array( $name, $wgWhitelistRead ) ) {
1052                                 return true;
1053                         }
1054
1055                         # Compatibility with old settings
1056                         if( $wgWhitelistRead && $this->getNamespace() == NS_MAIN ) {
1057                                 if( in_array( ':' . $name, $wgWhitelistRead ) ) {
1058                                         return true;
1059                                 }
1060                         }
1061                 }
1062                 return false;
1063         }
1064
1065         /**
1066          * Is this a talk page of some sort?
1067          * @return bool
1068          * @access public
1069          */
1070         function isTalkPage() {
1071                 return Namespace::isTalk( $this->getNamespace() );
1072         }
1073
1074         /**
1075          * Is this a .css or .js subpage of a user page?
1076          * @return bool
1077          * @access public
1078          */
1079         function isCssJsSubpage() {
1080                 return ( NS_USER == $this->mNamespace and preg_match("/\\.(css|js)$/", $this->mTextform ) );
1081         }
1082         /**
1083          * Is this a .css subpage of a user page?
1084          * @return bool
1085          * @access public
1086          */
1087         function isCssSubpage() {
1088                 return ( NS_USER == $this->mNamespace and preg_match("/\\.css$/", $this->mTextform ) );
1089         }
1090         /**
1091          * Is this a .js subpage of a user page?
1092          * @return bool
1093          * @access public
1094          */
1095         function isJsSubpage() {
1096                 return ( NS_USER == $this->mNamespace and preg_match("/\\.js$/", $this->mTextform ) );
1097         }
1098         /**
1099          * Protect css/js subpages of user pages: can $wgUser edit
1100          * this page?
1101          *
1102          * @return boolean
1103          * @todo XXX: this might be better using restrictions
1104          * @access public
1105          */
1106         function userCanEditCssJsSubpage() {
1107                 global $wgUser;
1108                 return ( $wgUser->isAllowed('editinterface') or preg_match('/^'.preg_quote($wgUser->getName(), '/').'\//', $this->mTextform) );
1109         }
1110
1111         /**
1112          * Loads a string into mRestrictions array
1113          * @param string $res restrictions in string format
1114          * @access public
1115          */
1116         function loadRestrictions( $res ) {
1117                 foreach( explode( ':', trim( $res ) ) as $restrict ) {
1118                         $temp = explode( '=', trim( $restrict ) );
1119                         if(count($temp) == 1) {
1120                                 // old format should be treated as edit/move restriction
1121                                 $this->mRestrictions["edit"] = explode( ',', trim( $temp[0] ) );
1122                                 $this->mRestrictions["move"] = explode( ',', trim( $temp[0] ) );
1123                         } else {
1124                                 $this->mRestrictions[$temp[0]] = explode( ',', trim( $temp[1] ) );
1125                         }
1126                 }
1127                 $this->mRestrictionsLoaded = true;
1128         }
1129
1130         /**
1131          * Accessor/initialisation for mRestrictions
1132          * @param string $action action that permission needs to be checked for
1133          * @return array the array of groups allowed to edit this article
1134          * @access public
1135          */
1136         function getRestrictions($action) {
1137                 $id = $this->getArticleID();
1138                 if ( 0 == $id ) { return array(); }
1139
1140                 if ( ! $this->mRestrictionsLoaded ) {
1141                         $dbr =& wfGetDB( DB_SLAVE );
1142                         $res = $dbr->selectField( 'page', 'page_restrictions', 'page_id='.$id );
1143                         $this->loadRestrictions( $res );
1144                 }
1145                 if( isset( $this->mRestrictions[$action] ) ) {
1146                         return $this->mRestrictions[$action];
1147                 }
1148                 return array();
1149         }
1150
1151         /**
1152          * Is there a version of this page in the deletion archive?
1153          * @return int the number of archived revisions
1154          * @access public
1155          */
1156         function isDeleted() {
1157                 $fname = 'Title::isDeleted';
1158                 if ( $this->getNamespace() < 0 ) {
1159                         $n = 0;
1160                 } else {
1161                         $dbr =& wfGetDB( DB_SLAVE );
1162                         $n = $dbr->selectField( 'archive', 'COUNT(*)', array( 'ar_namespace' => $this->getNamespace(),
1163                                 'ar_title' => $this->getDBkey() ), $fname );
1164                 }
1165                 return (int)$n;
1166         }
1167
1168         /**
1169          * Get the article ID for this Title from the link cache,
1170          * adding it if necessary
1171          * @param int $flags a bit field; may be GAID_FOR_UPDATE to select
1172          *      for update
1173          * @return int the ID
1174          * @access public
1175          */
1176         function getArticleID( $flags = 0 ) {
1177                 $linkCache =& LinkCache::singleton();
1178                 if ( $flags & GAID_FOR_UPDATE ) {
1179                         $oldUpdate = $linkCache->forUpdate( true );
1180                         $this->mArticleID = $linkCache->addLinkObj( $this );
1181                         $linkCache->forUpdate( $oldUpdate );
1182                 } else {
1183                         if ( -1 == $this->mArticleID ) {
1184                                 $this->mArticleID = $linkCache->addLinkObj( $this );
1185                         }
1186                 }
1187                 return $this->mArticleID;
1188         }
1189
1190         function getLatestRevID() {
1191                 if ($this->mLatestID !== false)
1192                         return $this->mLatestID;
1193
1194                 $db =& wfGetDB(DB_SLAVE);
1195                 return $this->mLatestID = $db->selectField( 'revision',
1196                         "max(rev_id)",
1197                         array('rev_page' => $this->getArticleID()),
1198                         'Title::getLatestRevID' );
1199         }
1200
1201         /**
1202          * This clears some fields in this object, and clears any associated
1203          * keys in the "bad links" section of the link cache.
1204          *
1205          * - This is called from Article::insertNewArticle() to allow
1206          * loading of the new page_id. It's also called from
1207          * Article::doDeleteArticle()
1208          *
1209          * @param int $newid the new Article ID
1210          * @access public
1211          */
1212         function resetArticleID( $newid ) {
1213                 $linkCache =& LinkCache::singleton();
1214                 $linkCache->clearBadLink( $this->getPrefixedDBkey() );
1215
1216                 if ( 0 == $newid ) { $this->mArticleID = -1; }
1217                 else { $this->mArticleID = $newid; }
1218                 $this->mRestrictionsLoaded = false;
1219                 $this->mRestrictions = array();
1220         }
1221
1222         /**
1223          * Updates page_touched for this page; called from LinksUpdate.php
1224          * @return bool true if the update succeded
1225          * @access public
1226          */
1227         function invalidateCache() {
1228                 global $wgUseFileCache;
1229
1230                 if ( wfReadOnly() ) {
1231                         return;
1232                 }
1233
1234                 $dbw =& wfGetDB( DB_MASTER );
1235                 $success = $dbw->update( 'page',
1236                         array( /* SET */
1237                                 'page_touched' => $dbw->timestamp()
1238                         ), array( /* WHERE */
1239                                 'page_namespace' => $this->getNamespace() ,
1240                                 'page_title' => $this->getDBkey()
1241                         ), 'Title::invalidateCache'
1242                 );
1243
1244                 if ($wgUseFileCache) {
1245                         $cache = new CacheManager($this);
1246                         @unlink($cache->fileCacheName());
1247                 }
1248
1249                 return $success;
1250         }
1251
1252         /**
1253          * Prefix some arbitrary text with the namespace or interwiki prefix
1254          * of this object
1255          *
1256          * @param string $name the text
1257          * @return string the prefixed text
1258          * @access private
1259          */
1260         /* private */ function prefix( $name ) {
1261                 global $wgContLang;
1262
1263                 $p = '';
1264                 if ( '' != $this->mInterwiki ) {
1265                         $p = $this->mInterwiki . ':';
1266                 }
1267                 if ( 0 != $this->mNamespace ) {
1268                         $p .= $wgContLang->getNsText( $this->mNamespace ) . ':';
1269                 }
1270                 return $p . $name;
1271         }
1272
1273         /**
1274          * Secure and split - main initialisation function for this object
1275          *
1276          * Assumes that mDbkeyform has been set, and is urldecoded
1277          * and uses underscores, but not otherwise munged.  This function
1278          * removes illegal characters, splits off the interwiki and
1279          * namespace prefixes, sets the other forms, and canonicalizes
1280          * everything.
1281          * @return bool true on success
1282          * @access private
1283          */
1284         /* private */ function secureAndSplit() {
1285                 global $wgContLang, $wgLocalInterwiki, $wgCapitalLinks;
1286                 $fname = 'Title::secureAndSplit';
1287                 wfProfileIn( $fname );
1288
1289                 # Initialisation
1290                 static $rxTc = false;
1291                 if( !$rxTc ) {
1292                         # % is needed as well
1293                         $rxTc = '/[^' . Title::legalChars() . ']|%[0-9A-Fa-f]{2}/S';
1294                 }
1295
1296                 $this->mInterwiki = $this->mFragment = '';
1297                 $this->mNamespace = $this->mDefaultNamespace; # Usually NS_MAIN
1298
1299                 # Clean up whitespace
1300                 #
1301                 $t = preg_replace( '/[ _]+/', '_', $this->mDbkeyform );
1302                 $t = trim( $t, '_' );
1303
1304                 if ( '' == $t ) {
1305                         wfProfileOut( $fname );
1306                         return false;
1307                 }
1308
1309                 if( false !== strpos( $t, UTF8_REPLACEMENT ) ) {
1310                         # Contained illegal UTF-8 sequences or forbidden Unicode chars.
1311                         wfProfileOut( $fname );
1312                         return false;
1313                 }
1314
1315                 $this->mDbkeyform = $t;
1316
1317                 # Initial colon indicates main namespace rather than specified default
1318                 # but should not create invalid {ns,title} pairs such as {0,Project:Foo}
1319                 if ( ':' == $t{0} ) {
1320                         $this->mNamespace = NS_MAIN;
1321                         $t = substr( $t, 1 ); # remove the colon but continue processing
1322                 }
1323
1324                 # Namespace or interwiki prefix
1325                 $firstPass = true;
1326                 do {
1327                         if ( preg_match( "/^(.+?)_*:_*(.*)$/S", $t, $m ) ) {
1328                                 $p = $m[1];
1329                                 $lowerNs = strtolower( $p );
1330                                 if ( $ns = Namespace::getCanonicalIndex( $lowerNs ) ) {
1331                                         # Canonical namespace
1332                                         $t = $m[2];
1333                                         $this->mNamespace = $ns;
1334                                 } elseif ( $ns = $wgContLang->getNsIndex( $lowerNs )) {
1335                                         # Ordinary namespace
1336                                         $t = $m[2];
1337                                         $this->mNamespace = $ns;
1338                                 } elseif( $this->getInterwikiLink( $p ) ) {
1339                                         if( !$firstPass ) {
1340                                                 # Can't make a local interwiki link to an interwiki link.
1341                                                 # That's just crazy!
1342                                                 wfProfileOut( $fname );
1343                                                 return false;
1344                                         }
1345
1346                                         # Interwiki link
1347                                         $t = $m[2];
1348                                         $this->mInterwiki = strtolower( $p );
1349
1350                                         # Redundant interwiki prefix to the local wiki
1351                                         if ( 0 == strcasecmp( $this->mInterwiki, $wgLocalInterwiki ) ) {
1352                                                 if( $t == '' ) {
1353                                                         # Can't have an empty self-link
1354                                                         wfProfileOut( $fname );
1355                                                         return false;
1356                                                 }
1357                                                 $this->mInterwiki = '';
1358                                                 $firstPass = false;
1359                                                 # Do another namespace split...
1360                                                 continue;
1361                                         }
1362                                 }
1363                                 # If there's no recognized interwiki or namespace,
1364                                 # then let the colon expression be part of the title.
1365                         }
1366                         break;
1367                 } while( true );
1368                 $r = $t;
1369
1370                 # We already know that some pages won't be in the database!
1371                 #
1372                 if ( '' != $this->mInterwiki || -1 == $this->mNamespace ) {
1373                         $this->mArticleID = 0;
1374                 }
1375                 $f = strstr( $r, '#' );
1376                 if ( false !== $f ) {
1377                         $this->mFragment = substr( $f, 1 );
1378                         $r = substr( $r, 0, strlen( $r ) - strlen( $f ) );
1379                         # remove whitespace again: prevents "Foo_bar_#"
1380                         # becoming "Foo_bar_"
1381                         $r = preg_replace( '/_*$/', '', $r );
1382                 }
1383
1384                 # Reject illegal characters.
1385                 #
1386                 if( preg_match( $rxTc, $r ) ) {
1387                         wfProfileOut( $fname );
1388                         return false;
1389                 }
1390
1391                 /**
1392                  * Pages with "/./" or "/../" appearing in the URLs will
1393                  * often be unreachable due to the way web browsers deal
1394                  * with 'relative' URLs. Forbid them explicitly.
1395                  */
1396                 if ( strpos( $r, '.' ) !== false &&
1397                      ( $r === '.' || $r === '..' ||
1398                        strpos( $r, './' ) === 0  ||
1399                        strpos( $r, '../' ) === 0 ||
1400                        strpos( $r, '/./' ) !== false ||
1401                        strpos( $r, '/../' ) !== false ) )
1402                 {
1403                         wfProfileOut( $fname );
1404                         return false;
1405                 }
1406
1407                 # We shouldn't need to query the DB for the size.
1408                 #$maxSize = $dbr->textFieldSize( 'page', 'page_title' );
1409                 if ( strlen( $r ) > 255 ) {
1410                         wfProfileOut( $fname );
1411                         return false;
1412                 }
1413
1414                 /**
1415                  * Normally, all wiki links are forced to have
1416                  * an initial capital letter so [[foo]] and [[Foo]]
1417                  * point to the same place.
1418                  *
1419                  * Don't force it for interwikis, since the other
1420                  * site might be case-sensitive.
1421                  */
1422                 if( $wgCapitalLinks && $this->mInterwiki == '') {
1423                         $t = $wgContLang->ucfirst( $r );
1424                 } else {
1425                         $t = $r;
1426                 }
1427
1428                 /**
1429                  * Can't make a link to a namespace alone...
1430                  * "empty" local links can only be self-links
1431                  * with a fragment identifier.
1432                  */
1433                 if( $t == '' &&
1434                         $this->mInterwiki == '' &&
1435                         $this->mNamespace != NS_MAIN ) {
1436                         wfProfileOut( $fname );
1437                         return false;
1438                 }
1439
1440                 # Fill fields
1441                 $this->mDbkeyform = $t;
1442                 $this->mUrlform = wfUrlencode( $t );
1443
1444                 $this->mTextform = str_replace( '_', ' ', $t );
1445
1446                 wfProfileOut( $fname );
1447                 return true;
1448         }
1449
1450         /**
1451          * Get a Title object associated with the talk page of this article
1452          * @return Title the object for the talk page
1453          * @access public
1454          */
1455         function getTalkPage() {
1456                 return Title::makeTitle( Namespace::getTalk( $this->getNamespace() ), $this->getDBkey() );
1457         }
1458
1459         /**
1460          * Get a title object associated with the subject page of this
1461          * talk page
1462          *
1463          * @return Title the object for the subject page
1464          * @access public
1465          */
1466         function getSubjectPage() {
1467                 return Title::makeTitle( Namespace::getSubject( $this->getNamespace() ), $this->getDBkey() );
1468         }
1469
1470         /**
1471          * Get an array of Title objects linking to this Title
1472          * Also stores the IDs in the link cache.
1473          *
1474          * @param string $options may be FOR UPDATE
1475          * @return array the Title objects linking here
1476          * @access public
1477          */
1478         function getLinksTo( $options = '', $table = 'pagelinks', $prefix = 'pl' ) {
1479                 $linkCache =& LinkCache::singleton();
1480                 $id = $this->getArticleID();
1481
1482                 if ( $options ) {
1483                         $db =& wfGetDB( DB_MASTER );
1484                 } else {
1485                         $db =& wfGetDB( DB_SLAVE );
1486                 }
1487
1488                 $res = $db->select( array( 'page', $table ),
1489                         array( 'page_namespace', 'page_title', 'page_id' ),
1490                         array(
1491                                 "{$prefix}_from=page_id",
1492                                 "{$prefix}_namespace" => $this->getNamespace(),
1493                                 "{$prefix}_title"     => $this->getDbKey() ),
1494                         'Title::getLinksTo',
1495                         $options );
1496
1497                 $retVal = array();
1498                 if ( $db->numRows( $res ) ) {
1499                         while ( $row = $db->fetchObject( $res ) ) {
1500                                 if ( $titleObj = Title::makeTitle( $row->page_namespace, $row->page_title ) ) {
1501                                         $linkCache->addGoodLinkObj( $row->page_id, $titleObj );
1502                                         $retVal[] = $titleObj;
1503                                 }
1504                         }
1505                 }
1506                 $db->freeResult( $res );
1507                 return $retVal;
1508         }
1509
1510         /**
1511          * Get an array of Title objects using this Title as a template
1512          * Also stores the IDs in the link cache.
1513          *
1514          * @param string $options may be FOR UPDATE
1515          * @return array the Title objects linking here
1516          * @access public
1517          */
1518         function getTemplateLinksTo( $options = '' ) {
1519                 return $this->getLinksTo( $options, 'templatelinks', 'tl' );
1520         }
1521
1522         /**
1523          * Get an array of Title objects referring to non-existent articles linked from this page
1524          *
1525          * @param string $options may be FOR UPDATE
1526          * @return array the Title objects
1527          * @access public
1528          */
1529         function getBrokenLinksFrom( $options = '' ) {
1530                 if ( $options ) {
1531                         $db =& wfGetDB( DB_MASTER );
1532                 } else {
1533                         $db =& wfGetDB( DB_SLAVE );
1534                 }
1535
1536                 $res = $db->safeQuery(
1537                           "SELECT pl_namespace, pl_title
1538                              FROM !
1539                         LEFT JOIN !
1540                                ON pl_namespace=page_namespace
1541                               AND pl_title=page_title
1542                             WHERE pl_from=?
1543                               AND page_namespace IS NULL
1544                                   !",
1545                         $db->tableName( 'pagelinks' ),
1546                         $db->tableName( 'page' ),
1547                         $this->getArticleId(),
1548                         $options );
1549
1550                 $retVal = array();
1551                 if ( $db->numRows( $res ) ) {
1552                         while ( $row = $db->fetchObject( $res ) ) {
1553                                 $retVal[] = Title::makeTitle( $row->pl_namespace, $row->pl_title );
1554                         }
1555                 }
1556                 $db->freeResult( $res );
1557                 return $retVal;
1558         }
1559
1560
1561         /**
1562          * Get a list of URLs to purge from the Squid cache when this
1563          * page changes
1564          *
1565          * @return array the URLs
1566          * @access public
1567          */
1568         function getSquidURLs() {
1569                 return array(
1570                         $this->getInternalURL(),
1571                         $this->getInternalURL( 'action=history' )
1572                 );
1573         }
1574
1575         /**
1576          * Move this page without authentication
1577          * @param Title &$nt the new page Title
1578          * @access public
1579          */
1580         function moveNoAuth( &$nt ) {
1581                 return $this->moveTo( $nt, false );
1582         }
1583
1584         /**
1585          * Check whether a given move operation would be valid.
1586          * Returns true if ok, or a message key string for an error message
1587          * if invalid. (Scarrrrry ugly interface this.)
1588          * @param Title &$nt the new title
1589          * @param bool $auth indicates whether $wgUser's permissions
1590          *      should be checked
1591          * @return mixed true on success, message name on failure
1592          * @access public
1593          */
1594         function isValidMoveOperation( &$nt, $auth = true ) {
1595                 global $wgUser;
1596                 if( !$this or !$nt ) {
1597                         return 'badtitletext';
1598                 }
1599                 if( $this->equals( $nt ) ) {
1600                         return 'selfmove';
1601                 }
1602                 if( !$this->isMovable() || !$nt->isMovable() ) {
1603                         return 'immobile_namespace';
1604                 }
1605
1606                 $oldid = $this->getArticleID();
1607                 $newid = $nt->getArticleID();
1608
1609                 if ( strlen( $nt->getDBkey() ) < 1 ) {
1610                         return 'articleexists';
1611                 }
1612                 if ( ( '' == $this->getDBkey() ) ||
1613                          ( !$oldid ) ||
1614                      ( '' == $nt->getDBkey() ) ) {
1615                         return 'badarticleerror';
1616                 }
1617
1618                 if ( $auth && (
1619                                 !$this->userCanEdit() || !$nt->userCanEdit() ||
1620                                 !$this->userCanMove() || !$nt->userCanMove() ) ) {
1621                         return 'protectedpage';
1622                 }
1623
1624                 # The move is allowed only if (1) the target doesn't exist, or
1625                 # (2) the target is a redirect to the source, and has no history
1626                 # (so we can undo bad moves right after they're done).
1627
1628                 if ( 0 != $newid ) { # Target exists; check for validity
1629                         if ( ! $this->isValidMoveTarget( $nt ) ) {
1630                                 return 'articleexists';
1631                         }
1632                 }
1633                 return true;
1634         }
1635
1636         /**
1637          * Move a title to a new location
1638          * @param Title &$nt the new title
1639          * @param bool $auth indicates whether $wgUser's permissions
1640          *      should be checked
1641          * @return mixed true on success, message name on failure
1642          * @access public
1643          */
1644         function moveTo( &$nt, $auth = true, $reason = '' ) {
1645                 $err = $this->isValidMoveOperation( $nt, $auth );
1646                 if( is_string( $err ) ) {
1647                         return $err;
1648                 }
1649
1650                 $pageid = $this->getArticleID();
1651                 if( $nt->exists() ) {
1652                         $this->moveOverExistingRedirect( $nt, $reason );
1653                         $pageCountChange = 0;
1654                 } else { # Target didn't exist, do normal move.
1655                         $this->moveToNewTitle( $nt, $reason );
1656                         $pageCountChange = 1;
1657                 }
1658                 $redirid = $this->getArticleID();
1659
1660                 # Fixing category links (those without piped 'alternate' names) to be sorted under the new title
1661                 $dbw =& wfGetDB( DB_MASTER );
1662                 $categorylinks = $dbw->tableName( 'categorylinks' );
1663                 $sql = "UPDATE $categorylinks SET cl_sortkey=" . $dbw->addQuotes( $nt->getPrefixedText() ) .
1664                         " WHERE cl_from=" . $dbw->addQuotes( $pageid ) .
1665                         " AND cl_sortkey=" . $dbw->addQuotes( $this->getPrefixedText() );
1666                 $dbw->query( $sql, 'SpecialMovepage::doSubmit' );
1667
1668                 # Update watchlists
1669
1670                 $oldnamespace = $this->getNamespace() & ~1;
1671                 $newnamespace = $nt->getNamespace() & ~1;
1672                 $oldtitle = $this->getDBkey();
1673                 $newtitle = $nt->getDBkey();
1674
1675                 if( $oldnamespace != $newnamespace || $oldtitle != $newtitle ) {
1676                         WatchedItem::duplicateEntries( $this, $nt );
1677                 }
1678
1679                 # Update search engine
1680                 $u = new SearchUpdate( $pageid, $nt->getPrefixedDBkey() );
1681                 $u->doUpdate();
1682                 $u = new SearchUpdate( $redirid, $this->getPrefixedDBkey(), '' );
1683                 $u->doUpdate();
1684
1685                 # Update site_stats
1686                 if ( $this->getNamespace() == NS_MAIN and $nt->getNamespace() != NS_MAIN ) {
1687                         # Moved out of main namespace
1688                         # not viewed, edited, removing
1689                         $u = new SiteStatsUpdate( 0, 1, -1, $pageCountChange);
1690                 } elseif ( $this->getNamespace() != NS_MAIN and $nt->getNamespace() == NS_MAIN ) {
1691                         # Moved into main namespace
1692                         # not viewed, edited, adding
1693                         $u = new SiteStatsUpdate( 0, 1, +1, $pageCountChange );
1694                 } elseif ( $pageCountChange ) {
1695                         # Added redirect
1696                         $u = new SiteStatsUpdate( 0, 0, 0, 1 );
1697                 } else{
1698                         $u = false;
1699                 }
1700                 if ( $u ) {
1701                         $u->doUpdate();
1702                 }
1703
1704                 global $wgUser;
1705                 wfRunHooks( 'TitleMoveComplete', array( &$this, &$nt, &$wgUser, $pageid, $redirid ) );
1706                 return true;
1707         }
1708
1709         /**
1710          * Move page to a title which is at present a redirect to the
1711          * source page
1712          *
1713          * @param Title &$nt the page to move to, which should currently
1714          *      be a redirect
1715          * @access private
1716          */
1717         function moveOverExistingRedirect( &$nt, $reason = '' ) {
1718                 global $wgUser, $wgUseSquid, $wgMwRedir;
1719                 $fname = 'Title::moveOverExistingRedirect';
1720                 $comment = wfMsgForContent( '1movedto2', $this->getPrefixedText(), $nt->getPrefixedText() );
1721
1722                 if ( $reason ) {
1723                         $comment .= ": $reason";
1724                 }
1725
1726                 $now = wfTimestampNow();
1727                 $rand = wfRandom();
1728                 $newid = $nt->getArticleID();
1729                 $oldid = $this->getArticleID();
1730                 $dbw =& wfGetDB( DB_MASTER );
1731                 $linkCache =& LinkCache::singleton();
1732
1733                 # Delete the old redirect. We don't save it to history since
1734                 # by definition if we've got here it's rather uninteresting.
1735                 # We have to remove it so that the next step doesn't trigger
1736                 # a conflict on the unique namespace+title index...
1737                 $dbw->delete( 'page', array( 'page_id' => $newid ), $fname );
1738
1739                 # Save a null revision in the page's history notifying of the move
1740                 $nullRevision = Revision::newNullRevision( $dbw, $oldid, $comment, true );
1741                 $nullRevId = $nullRevision->insertOn( $dbw );
1742
1743                 # Change the name of the target page:
1744                 $dbw->update( 'page',
1745                         /* SET */ array(
1746                                 'page_touched'   => $dbw->timestamp($now),
1747                                 'page_namespace' => $nt->getNamespace(),
1748                                 'page_title'     => $nt->getDBkey(),
1749                                 'page_latest'    => $nullRevId,
1750                         ),
1751                         /* WHERE */ array( 'page_id' => $oldid ),
1752                         $fname
1753                 );
1754                 $linkCache->clearLink( $nt->getPrefixedDBkey() );
1755
1756                 # Recreate the redirect, this time in the other direction.
1757                 $redirectText = $wgMwRedir->getSynonym( 0 ) . ' [[' . $nt->getPrefixedText() . "]]\n";
1758                 $redirectArticle = new Article( $this );
1759                 $newid = $redirectArticle->insertOn( $dbw );
1760                 $redirectRevision = new Revision( array(
1761                         'page'    => $newid,
1762                         'comment' => $comment,
1763                         'text'    => $redirectText ) );
1764                 $revid = $redirectRevision->insertOn( $dbw );
1765                 $redirectArticle->updateRevisionOn( $dbw, $redirectRevision, 0 );
1766                 $linkCache->clearLink( $this->getPrefixedDBkey() );
1767
1768                 # Log the move
1769                 $log = new LogPage( 'move' );
1770                 $log->addEntry( 'move_redir', $this, $reason, array( 1 => $nt->getPrefixedText() ) );
1771
1772                 # Now, we record the link from the redirect to the new title.
1773                 # It should have no other outgoing links...
1774                 $dbw->delete( 'pagelinks', array( 'pl_from' => $newid ), $fname );
1775                 $dbw->insert( 'pagelinks',
1776                         array(
1777                                 'pl_from'      => $newid,
1778                                 'pl_namespace' => $nt->getNamespace(),
1779                                 'pl_title'     => $nt->getDbKey() ),
1780                         $fname );
1781
1782                 # Purge squid
1783                 if ( $wgUseSquid ) {
1784                         $urls = array_merge( $nt->getSquidURLs(), $this->getSquidURLs() );
1785                         $u = new SquidUpdate( $urls );
1786                         $u->doUpdate();
1787                 }
1788         }
1789
1790         /**
1791          * Move page to non-existing title.
1792          * @param Title &$nt the new Title
1793          * @access private
1794          */
1795         function moveToNewTitle( &$nt, $reason = '' ) {
1796                 global $wgUser, $wgUseSquid;
1797                 global $wgMwRedir;
1798                 $fname = 'MovePageForm::moveToNewTitle';
1799                 $comment = wfMsgForContent( '1movedto2', $this->getPrefixedText(), $nt->getPrefixedText() );
1800                 if ( $reason ) {
1801                         $comment .= ": $reason";
1802                 }
1803
1804                 $newid = $nt->getArticleID();
1805                 $oldid = $this->getArticleID();
1806                 $dbw =& wfGetDB( DB_MASTER );
1807                 $now = $dbw->timestamp();
1808                 $rand = wfRandom();
1809                 $linkCache =& LinkCache::singleton();
1810
1811                 # Save a null revision in the page's history notifying of the move
1812                 $nullRevision = Revision::newNullRevision( $dbw, $oldid, $comment, true );
1813                 $nullRevId = $nullRevision->insertOn( $dbw );
1814
1815                 # Rename cur entry
1816                 $dbw->update( 'page',
1817                         /* SET */ array(
1818                                 'page_touched'   => $now,
1819                                 'page_namespace' => $nt->getNamespace(),
1820                                 'page_title'     => $nt->getDBkey(),
1821                                 'page_latest'    => $nullRevId,
1822                         ),
1823                         /* WHERE */ array( 'page_id' => $oldid ),
1824                         $fname
1825                 );
1826
1827                 $linkCache->clearLink( $nt->getPrefixedDBkey() );
1828
1829                 # Insert redirect
1830                 $redirectText = $wgMwRedir->getSynonym( 0 ) . ' [[' . $nt->getPrefixedText() . "]]\n";
1831                 $redirectArticle = new Article( $this );
1832                 $newid = $redirectArticle->insertOn( $dbw );
1833                 $redirectRevision = new Revision( array(
1834                         'page'    => $newid,
1835                         'comment' => $comment,
1836                         'text'    => $redirectText ) );
1837                 $revid = $redirectRevision->insertOn( $dbw );
1838                 $redirectArticle->updateRevisionOn( $dbw, $redirectRevision, 0 );
1839                 $linkCache->clearLink( $this->getPrefixedDBkey() );
1840
1841                 # Log the move
1842                 $log = new LogPage( 'move' );
1843                 $log->addEntry( 'move', $this, $reason, array( 1 => $nt->getPrefixedText()) );
1844
1845                 # Purge caches as per article creation
1846                 Article::onArticleCreate( $nt );
1847
1848                 # Record the just-created redirect's linking to the page
1849                 $dbw->insert( 'pagelinks',
1850                         array(
1851                                 'pl_from'      => $newid,
1852                                 'pl_namespace' => $nt->getNamespace(),
1853                                 'pl_title'     => $nt->getDBkey() ),
1854                         $fname );
1855
1856                 # Non-existent target may have had broken links to it; these must
1857                 # now be touched to update link coloring.
1858                 $nt->touchLinks();
1859
1860                 # Purge old title from squid
1861                 # The new title, and links to the new title, are purged in Article::onArticleCreate()
1862                 $titles = $nt->getLinksTo();
1863                 if ( $wgUseSquid ) {
1864                         $urls = $this->getSquidURLs();
1865                         foreach ( $titles as $linkTitle ) {
1866                                 $urls[] = $linkTitle->getInternalURL();
1867                         }
1868                         $u = new SquidUpdate( $urls );
1869                         $u->doUpdate();
1870                 }
1871         }
1872
1873         /**
1874          * Checks if $this can be moved to a given Title
1875          * - Selects for update, so don't call it unless you mean business
1876          *
1877          * @param Title &$nt the new title to check
1878          * @access public
1879          */
1880         function isValidMoveTarget( $nt ) {
1881
1882                 $fname = 'Title::isValidMoveTarget';
1883                 $dbw =& wfGetDB( DB_MASTER );
1884
1885                 # Is it a redirect?
1886                 $id  = $nt->getArticleID();
1887                 $obj = $dbw->selectRow( array( 'page', 'revision', 'text'),
1888                         array( 'page_is_redirect','old_text','old_flags' ),
1889                         array( 'page_id' => $id, 'page_latest=rev_id', 'rev_text_id=old_id' ),
1890                         $fname, 'FOR UPDATE' );
1891
1892                 if ( !$obj || 0 == $obj->page_is_redirect ) {
1893                         # Not a redirect
1894                         return false;
1895                 }
1896                 $text = Revision::getRevisionText( $obj );
1897
1898                 # Does the redirect point to the source?
1899                 if ( preg_match( "/\\[\\[\\s*([^\\]\\|]*)]]/", $text, $m ) ) {
1900                         $redirTitle = Title::newFromText( $m[1] );
1901                         if( !is_object( $redirTitle ) ||
1902                                 $redirTitle->getPrefixedDBkey() != $this->getPrefixedDBkey() ) {
1903                                 return false;
1904                         }
1905                 } else {
1906                         # Fail safe
1907                         return false;
1908                 }
1909
1910                 # Does the article have a history?
1911                 $row = $dbw->selectRow( array( 'page', 'revision'),
1912                         array( 'rev_id' ),
1913                         array( 'page_namespace' => $nt->getNamespace(),
1914                                 'page_title' => $nt->getDBkey(),
1915                                 'page_id=rev_page AND page_latest != rev_id'
1916                         ), $fname, 'FOR UPDATE'
1917                 );
1918
1919                 # Return true if there was no history
1920                 return $row === false;
1921         }
1922
1923         /**
1924          * Create a redirect; fails if the title already exists; does
1925          * not notify RC
1926          *
1927          * @param Title $dest the destination of the redirect
1928          * @param string $comment the comment string describing the move
1929          * @return bool true on success
1930          * @access public
1931          */
1932         function createRedirect( $dest, $comment ) {
1933                 global $wgUser;
1934                 if ( $this->getArticleID() ) {
1935                         return false;
1936                 }
1937
1938                 $fname = 'Title::createRedirect';
1939                 $dbw =& wfGetDB( DB_MASTER );
1940
1941                 $article = new Article( $this );
1942                 $newid = $article->insertOn( $dbw );
1943                 $revision = new Revision( array(
1944                         'page'      => $newid,
1945                         'comment'   => $comment,
1946                         'text'      => "#REDIRECT [[" . $dest->getPrefixedText() . "]]\n",
1947                         ) );
1948                 $revisionId = $revision->insertOn( $dbw );
1949                 $article->updateRevisionOn( $dbw, $revision, 0 );
1950
1951                 # Link table
1952                 $dbw->insert( 'pagelinks',
1953                         array(
1954                                 'pl_from'      => $newid,
1955                                 'pl_namespace' => $dest->getNamespace(),
1956                                 'pl_title'     => $dest->getDbKey()
1957                         ), $fname
1958                 );
1959
1960                 Article::onArticleCreate( $this );
1961                 return true;
1962         }
1963
1964         /**
1965          * Get categories to which this Title belongs and return an array of
1966          * categories' names.
1967          *
1968          * @return array an array of parents in the form:
1969          *      $parent => $currentarticle
1970          * @access public
1971          */
1972         function getParentCategories() {
1973                 global $wgContLang,$wgUser;
1974
1975                 $titlekey = $this->getArticleId();
1976                 $dbr =& wfGetDB( DB_SLAVE );
1977                 $categorylinks = $dbr->tableName( 'categorylinks' );
1978
1979                 # NEW SQL
1980                 $sql = "SELECT * FROM $categorylinks"
1981                      ." WHERE cl_from='$titlekey'"
1982                          ." AND cl_from <> '0'"
1983                          ." ORDER BY cl_sortkey";
1984
1985                 $res = $dbr->query ( $sql ) ;
1986
1987                 if($dbr->numRows($res) > 0) {
1988                         while ( $x = $dbr->fetchObject ( $res ) )
1989                                 //$data[] = Title::newFromText($wgContLang->getNSText ( NS_CATEGORY ).':'.$x->cl_to);
1990                                 $data[$wgContLang->getNSText ( NS_CATEGORY ).':'.$x->cl_to] = $this->getFullText();
1991                         $dbr->freeResult ( $res ) ;
1992                 } else {
1993                         $data = '';
1994                 }
1995                 return $data;
1996         }
1997
1998         /**
1999          * Get a tree of parent categories
2000          * @param array $children an array with the children in the keys, to check for circular refs
2001          * @return array
2002          * @access public
2003          */
2004         function getParentCategoryTree( $children = array() ) {
2005                 $parents = $this->getParentCategories();
2006
2007                 if($parents != '') {
2008                         foreach($parents as $parent => $current) {
2009                                 if ( array_key_exists( $parent, $children ) ) {
2010                                         # Circular reference
2011                                         $stack[$parent] = array();
2012                                 } else {
2013                                         $nt = Title::newFromText($parent);
2014                                         $stack[$parent] = $nt->getParentCategoryTree( $children + array($parent => 1) );
2015                                 }
2016                         }
2017                         return $stack;
2018                 } else {
2019                         return array();
2020                 }
2021         }
2022
2023
2024         /**
2025          * Get an associative array for selecting this title from
2026          * the "page" table
2027          *
2028          * @return array
2029          * @access public
2030          */
2031         function pageCond() {
2032                 return array( 'page_namespace' => $this->mNamespace, 'page_title' => $this->mDbkeyform );
2033         }
2034
2035         /**
2036          * Get the revision ID of the previous revision
2037          *
2038          * @param integer $revision  Revision ID. Get the revision that was before this one.
2039          * @return interger $oldrevision|false
2040          */
2041         function getPreviousRevisionID( $revision ) {
2042                 $dbr =& wfGetDB( DB_SLAVE );
2043                 return $dbr->selectField( 'revision', 'rev_id',
2044                         'rev_page=' . intval( $this->getArticleId() ) .
2045                         ' AND rev_id<' . intval( $revision ) . ' ORDER BY rev_id DESC' );
2046         }
2047
2048         /**
2049          * Get the revision ID of the next revision
2050          *
2051          * @param integer $revision  Revision ID. Get the revision that was after this one.
2052          * @return interger $oldrevision|false
2053          */
2054         function getNextRevisionID( $revision ) {
2055                 $dbr =& wfGetDB( DB_SLAVE );
2056                 return $dbr->selectField( 'revision', 'rev_id',
2057                         'rev_page=' . intval( $this->getArticleId() ) .
2058                         ' AND rev_id>' . intval( $revision ) . ' ORDER BY rev_id' );
2059         }
2060
2061         /**
2062          * Compare with another title.
2063          *
2064          * @param Title $title
2065          * @return bool
2066          */
2067         function equals( $title ) {
2068                 return $this->getInterwiki() == $title->getInterwiki()
2069                         && $this->getNamespace() == $title->getNamespace()
2070                         && $this->getDbkey() == $title->getDbkey();
2071         }
2072
2073         /**
2074          * Check if page exists
2075          * @return bool
2076          */
2077         function exists() {
2078                 return $this->getArticleId() != 0;
2079         }
2080
2081         /**
2082          * Should a link should be displayed as a known link, just based on its title?
2083          *
2084          * Currently, a self-link with a fragment and special pages are in
2085          * this category. Special pages never exist in the database.
2086          */
2087         function isAlwaysKnown() {
2088                 return  $this->isExternal() || ( 0 == $this->mNamespace && "" == $this->mDbkeyform )
2089                   || NS_SPECIAL == $this->mNamespace;
2090         }
2091
2092         /**
2093          * Update page_touched timestamps on pages linking to this title.
2094          * In principal, this could be backgrounded and could also do squid
2095          * purging.
2096          */
2097         function touchLinks() {
2098                 $fname = 'Title::touchLinks';
2099
2100                 $dbw =& wfGetDB( DB_MASTER );
2101
2102                 $res = $dbw->select( 'pagelinks',
2103                         array( 'pl_from' ),
2104                         array(
2105                                 'pl_namespace' => $this->getNamespace(),
2106                                 'pl_title'     => $this->getDbKey() ),
2107                         $fname );
2108
2109                 $toucharr = array();
2110                 while( $row = $dbw->fetchObject( $res ) ) {
2111                         $toucharr[] = $row->pl_from;
2112                 }
2113                 $dbw->freeResult( $res );
2114
2115                 if( $this->getNamespace() == NS_CATEGORY ) {
2116                         // Categories show up in a separate set of links as well
2117                         $res = $dbw->select( 'categorylinks',
2118                                 array( 'cl_from' ),
2119                                 array( 'cl_to' => $this->getDbKey() ),
2120                                 $fname );
2121                         while( $row = $dbw->fetchObject( $res ) ) {
2122                                 $toucharr[] = $row->cl_from;
2123                         }
2124                         $dbw->freeResult( $res );
2125                 }
2126
2127                 if (!count($toucharr))
2128                         return;
2129                 $dbw->update( 'page', /* SET */ array( 'page_touched' => $dbw->timestamp() ),
2130                                                         /* WHERE */ array( 'page_id' => $toucharr ),$fname);
2131         }
2132
2133         function trackbackURL() {
2134                 global $wgTitle, $wgScriptPath, $wgServer;
2135
2136                 return "$wgServer$wgScriptPath/trackback.php?article="
2137                         . htmlspecialchars(urlencode($wgTitle->getPrefixedDBkey()));
2138         }
2139
2140         function trackbackRDF() {
2141                 $url = htmlspecialchars($this->getFullURL());
2142                 $title = htmlspecialchars($this->getText());
2143                 $tburl = $this->trackbackURL();
2144
2145                 return "
2146 <rdf:RDF xmlns:rdf=\"http://www.w3.org/1999/02/22-rdf-syntax-ns#\"
2147          xmlns:dc=\"http://purl.org/dc/elements/1.1/\"
2148          xmlns:trackback=\"http://madskills.com/public/xml/rss/module/trackback/\">
2149 <rdf:Description
2150    rdf:about=\"$url\"
2151    dc:identifier=\"$url\"
2152    dc:title=\"$title\"
2153    trackback:ping=\"$tburl\" />
2154 </rdf:RDF>";
2155         }
2156 }
2157 ?>