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 define ( 'GAID_FOR_UPDATE', 1 );
  12
  13 # Title::newFromTitle maintains a cache to avoid
  14 # expensive re-normalization of commonly used titles.
  15 # On a batch operation this can become a memory leak
  16 # if not bounded. After hitting this many titles,
  17 # reset the cache.
  18 define( 'MW_TITLECACHE_MAX', 1000 );
  19
  20 /**
  21  * Title class
  22  * - Represents a title, which may contain an interwiki designation or namespace
  23  * - Can fetch various kinds of data from the database, albeit inefficiently.
  24  *
  25  * @package MediaWiki
  26  */
  27 class Title {
  28         /**
  29          * Static cache variables
  30          */
  31         static private $titleCache=array();
  32         static private $interwikiCache=array();
  33
  34
  35         /**
  36          * All member variables should be considered private
  37          * Please use the accessor functions
  38          */
  39
  40          /**#@+
  41          * @private
  42          */
  43
  44         var $mTextform;           # Text form (spaces not underscores) of the main part
  45         var $mUrlform;            # URL-encoded form of the main part
  46         var $mDbkeyform;          # Main part with underscores
  47         var $mNamespace;          # Namespace index, i.e. one of the NS_xxxx constants
  48         var $mInterwiki;          # Interwiki prefix (or null string)
  49         var $mFragment;           # Title fragment (i.e. the bit after the #)
  50         var $mArticleID;          # Article ID, fetched from the link cache on demand
  51         var $mLatestID;         # ID of most recent revision
  52         var $mRestrictions;       # Array of groups allowed to edit this article
  53                                 # Only null or "sysop" are supported
  54         var $mRestrictionsLoaded; # Boolean for initialisation on demand
  55         var $mPrefixedText;       # Text form including namespace/interwiki, initialised on demand
  56         var $mDefaultNamespace;   # Namespace index when there is no namespace
  57                             # Zero except in {{transclusion}} tags
  58         var $mWatched;      # Is $wgUser watching this page? NULL if unfilled, accessed through userIsWatching()
  59         /**#@-*/
  60
  61
  62         /**
  63          * Constructor
  64          * @private
  65          */
  66         /* private */ function Title() {
  67                 $this->mInterwiki = $this->mUrlform =
  68                 $this->mTextform = $this->mDbkeyform = '';
  69                 $this->mArticleID = -1;
  70                 $this->mNamespace = NS_MAIN;
  71                 $this->mRestrictionsLoaded = false;
  72                 $this->mRestrictions = array();
  73                 # Dont change the following, NS_MAIN is hardcoded in several place
  74                 # See bug #696
  75                 $this->mDefaultNamespace = NS_MAIN;
  76                 $this->mWatched = NULL;
  77                 $this->mLatestID = false;
  78         }
  79
  80         /**
  81          * Create a new Title from a prefixed DB key
  82          * @param string $key The database key, which has underscores
  83          *      instead of spaces, possibly including namespace and
  84          *      interwiki prefixes
  85          * @return Title the new object, or NULL on an error
  86          * @static
  87          * @access public
  88          */
  89         /* static */ function newFromDBkey( $key ) {
  90                 $t = new Title();
  91                 $t->mDbkeyform = $key;
  92                 if( $t->secureAndSplit() )
  93                         return $t;
  94                 else
  95                         return NULL;
  96         }
  97
  98         /**
  99          * Create a new Title from text, such as what one would
 100          * find in a link. Decodes any HTML entities in the text.
 101          *
 102          * @param string $text the link text; spaces, prefixes,
 103          *      and an initial ':' indicating the main namespace
 104          *      are accepted
 105          * @param int $defaultNamespace the namespace to use if
 106          *      none is specified by a prefix
 107          * @return Title the new object, or NULL on an error
 108          * @static
 109          * @access public
 110          */
 111         public static function newFromText( $text, $defaultNamespace = NS_MAIN ) {
 112                 $fname = 'Title::newFromText';
 113
 114                 if( is_object( $text ) ) {
 115                         throw new MWException( 'Title::newFromText given an object' );
 116                 }
 117
 118                 /**
 119                  * Wiki pages often contain multiple links to the same page.
 120                  * Title normalization and parsing can become expensive on
 121                  * pages with many links, so we can save a little time by
 122                  * caching them.
 123                  *
 124                  * In theory these are value objects and won't get changed...
 125                  */
 126                 if( $defaultNamespace == NS_MAIN && isset( Title::$titleCache[$text] ) ) {
 127                         return Title::$titleCache[$text];
 128                 }
 129
 130                 /**
 131                  * Convert things like &eacute; &#257; or &#x3017; into real text...
 132                  */
 133                 $filteredText = Sanitizer::decodeCharReferences( $text );
 134
 135                 $t = new Title();
 136                 $t->mDbkeyform = str_replace( ' ', '_', $filteredText );
 137                 $t->mDefaultNamespace = $defaultNamespace;
 138
 139                 static $cachedcount = 0 ;
 140                 if( $t->secureAndSplit() ) {
 141                         if( $defaultNamespace == NS_MAIN ) {
 142                                 if( $cachedcount >= MW_TITLECACHE_MAX ) {
 143                                         # Avoid memory leaks on mass operations...
 144                                         Title::$titleCache = array();
 145                                         $cachedcount=0;
 146                                 }
 147                                 $cachedcount++;
 148                                 Title::$titleCache[$text] =& $t;
 149                         }
 150                         return $t;
 151                 } else {
 152                         $ret = NULL;
 153                         return $ret;
 154                 }
 155         }
 156
 157         /**
 158          * Create a new Title from URL-encoded text. Ensures that
 159          * the given title's length does not exceed the maximum.
 160          * @param string $url the title, as might be taken from a URL
 161          * @return Title the new object, or NULL on an error
 162          * @static
 163          * @access public
 164          */
 165         function newFromURL( $url ) {
 166                 global $wgLegalTitleChars;
 167                 $t = new Title();
 168
 169                 # For compatibility with old buggy URLs. "+" is usually not valid in titles,
 170                 # but some URLs used it as a space replacement and they still come
 171                 # from some external search tools.
 172                 if ( strpos( $wgLegalTitleChars, '+' ) === false ) {
 173                         $url = str_replace( '+', ' ', $url );
 174                 }
 175
 176                 $t->mDbkeyform = str_replace( ' ', '_', $url );
 177                 if( $t->secureAndSplit() ) {
 178                         return $t;
 179                 } else {
 180                         return NULL;
 181                 }
 182         }
 183
 184         /**
 185          * Create a new Title from an article ID
 186          *
 187          * @todo This is inefficiently implemented, the page row is requested
 188          *       but not used for anything else
 189          *
 190          * @param int $id the page_id corresponding to the Title to create
 191          * @return Title the new object, or NULL on an error
 192          * @access public
 193          * @static
 194          */
 195         function newFromID( $id ) {
 196                 $fname = 'Title::newFromID';
 197                 $dbr =& wfGetDB( DB_SLAVE );
 198                 $row = $dbr->selectRow( 'page', array( 'page_namespace', 'page_title' ),
 199                         array( 'page_id' => $id ), $fname );
 200                 if ( $row !== false ) {
 201                         $title = Title::makeTitle( $row->page_namespace, $row->page_title );
 202                 } else {
 203                         $title = NULL;
 204                 }
 205                 return $title;
 206         }
 207
 208         /**
 209          * Make an array of titles from an array of IDs
 210          */
 211         function newFromIDs( $ids ) {
 212                 $dbr =& wfGetDB( DB_SLAVE );
 213                 $res = $dbr->select( 'page', array( 'page_namespace', 'page_title' ),
 214                         'page_id IN (' . $dbr->makeList( $ids ) . ')', __METHOD__ );
 215
 216                 $titles = array();
 217                 while ( $row = $dbr->fetchObject( $res ) ) {
 218                         $titles[] = Title::makeTitle( $row->page_namespace, $row->page_title );
 219                 }
 220                 return $titles;
 221         }
 222
 223         /**
 224          * Create a new Title from a namespace index and a DB key.
 225          * It's assumed that $ns and $title are *valid*, for instance when
 226          * they came directly from the database or a special page name.
 227          * For convenience, spaces are converted to underscores so that
 228          * eg user_text fields can be used directly.
 229          *
 230          * @param int $ns the namespace of the article
 231          * @param string $title the unprefixed database key form
 232          * @return Title the new object
 233          * @static
 234          * @access public
 235          */
 236         public static function &makeTitle( $ns, $title ) {
 237                 $t = new Title();
 238                 $t->mInterwiki = '';
 239                 $t->mFragment = '';
 240                 $t->mNamespace = intval( $ns );
 241                 $t->mDbkeyform = str_replace( ' ', '_', $title );
 242                 $t->mArticleID = ( $ns >= 0 ) ? -1 : 0;
 243                 $t->mUrlform = wfUrlencode( $t->mDbkeyform );
 244                 $t->mTextform = str_replace( '_', ' ', $title );
 245                 return $t;
 246         }
 247
 248         /**
 249          * Create a new Title from a namespace index and a DB key.
 250          * The parameters will be checked for validity, which is a bit slower
 251          * than makeTitle() but safer for user-provided data.
 252          *
 253          * @param int $ns the namespace of the article
 254          * @param string $title the database key form
 255          * @return Title the new object, or NULL on an error
 256          * @static
 257          * @access public
 258          */
 259         public static function makeTitleSafe( $ns, $title ) {
 260                 $t = new Title();
 261                 $t->mDbkeyform = Title::makeName( $ns, $title );
 262                 if( $t->secureAndSplit() ) {
 263                         return $t;
 264                 } else {
 265                         return NULL;
 266                 }
 267         }
 268
 269         /**
 270          * Create a new Title for the Main Page
 271          *
 272          * @static
 273          * @return Title the new object
 274          * @access public
 275          */
 276         public static function newMainPage() {
 277                 return Title::newFromText( wfMsgForContent( 'mainpage' ) );
 278         }
 279
 280         /**
 281          * Create a new Title for a redirect
 282          * @param string $text the redirect title text
 283          * @return Title the new object, or NULL if the text is not a
 284          *      valid redirect
 285          * @static
 286          * @access public
 287          */
 288         public static function newFromRedirect( $text ) {
 289                 $mwRedir = MagicWord::get( 'redirect' );
 290                 $rt = NULL;
 291                 if ( $mwRedir->matchStart( $text ) ) {
 292                         if ( preg_match( '/\[{2}(.*?)(?:\||\]{2})/', $text, $m ) ) {
 293                                 # categories are escaped using : for example one can enter:
 294                                 # #REDIRECT [[:Category:Music]]. Need to remove it.
 295                                 if ( substr($m[1],0,1) == ':') {
 296                                         # We don't want to keep the ':'
 297                                         $m[1] = substr( $m[1], 1 );
 298                                 }
 299
 300                                 $rt = Title::newFromText( $m[1] );
 301                                 # Disallow redirects to Special:Userlogout
 302                                 if ( !is_null($rt) && $rt->getNamespace() == NS_SPECIAL && preg_match( '/^Userlogout/i', $rt->getText() ) ) {
 303                                         $rt = NULL;
 304                                 }
 305                         }
 306                 }
 307                 return $rt;
 308         }
 309
 310 #----------------------------------------------------------------------------
 311 #       Static functions
 312 #----------------------------------------------------------------------------
 313
 314         /**
 315          * Get the prefixed DB key associated with an ID
 316          * @param int $id the page_id of the article
 317          * @return Title an object representing the article, or NULL
 318          *      if no such article was found
 319          * @static
 320          * @access public
 321          */
 322         function nameOf( $id ) {
 323                 $fname = 'Title::nameOf';
 324                 $dbr =& wfGetDB( DB_SLAVE );
 325
 326                 $s = $dbr->selectRow( 'page', array( 'page_namespace','page_title' ),  array( 'page_id' => $id ), $fname );
 327                 if ( $s === false ) { return NULL; }
 328
 329                 $n = Title::makeName( $s->page_namespace, $s->page_title );
 330                 return $n;
 331         }
 332
 333         /**
 334          * Get a regex character class describing the legal characters in a link
 335          * @return string the list of characters, not delimited
 336          * @static
 337          * @access public
 338          */
 339         public static function legalChars() {
 340                 global $wgLegalTitleChars;
 341                 return $wgLegalTitleChars;
 342         }
 343
 344         /**
 345          * Get a string representation of a title suitable for
 346          * including in a search index
 347          *
 348          * @param int $ns a namespace index
 349          * @param string $title text-form main part
 350          * @return string a stripped-down title string ready for the
 351          *      search index
 352          */
 353         /* static */ function indexTitle( $ns, $title ) {
 354                 global $wgContLang;
 355
 356                 $lc = SearchEngine::legalSearchChars() . '&#;';
 357                 $t = $wgContLang->stripForSearch( $title );
 358                 $t = preg_replace( "/[^{$lc}]+/", ' ', $t );
 359                 $t = strtolower( $t );
 360
 361                 # Handle 's, s'
 362                 $t = preg_replace( "/([{$lc}]+)'s( |$)/", "\\1 \\1's ", $t );
 363                 $t = preg_replace( "/([{$lc}]+)s'( |$)/", "\\1s ", $t );
 364
 365                 $t = preg_replace( "/\\s+/", ' ', $t );
 366
 367                 if ( $ns == NS_IMAGE ) {
 368                         $t = preg_replace( "/ (png|gif|jpg|jpeg|ogg)$/", "", $t );
 369                 }
 370                 return trim( $t );
 371         }
 372
 373         /*
 374          * Make a prefixed DB key from a DB key and a namespace index
 375          * @param int $ns numerical representation of the namespace
 376          * @param string $title the DB key form the title
 377          * @return string the prefixed form of the title
 378          */
 379         public static function makeName( $ns, $title ) {
 380                 global $wgContLang;
 381
 382                 $n = $wgContLang->getNsText( $ns );
 383                 return $n == '' ? $title : "$n:$title";
 384         }
 385
 386         /**
 387          * Returns the URL associated with an interwiki prefix
 388          * @param string $key the interwiki prefix (e.g. "MeatBall")
 389          * @return the associated URL, containing "$1", which should be
 390          *      replaced by an article title
 391          * @static (arguably)
 392          * @access public
 393          */
 394         function getInterwikiLink( $key )  {
 395                 global $wgMemc, $wgDBname, $wgInterwikiExpiry;
 396                 global $wgInterwikiCache;
 397                 $fname = 'Title::getInterwikiLink';
 398
 399                 $key = strtolower( $key );
 400
 401                 $k = $wgDBname.':interwiki:'.$key;
 402                 if( array_key_exists( $k, Title::$interwikiCache ) ) {
 403                         return Title::$interwikiCache[$k]->iw_url;
 404                 }
 405
 406                 if ($wgInterwikiCache) {
 407                         return Title::getInterwikiCached( $key );
 408                 }
 409
 410                 $s = $wgMemc->get( $k );
 411                 # Ignore old keys with no iw_local
 412                 if( $s && isset( $s->iw_local ) && isset($s->iw_trans)) {
 413                         Title::$interwikiCache[$k] = $s;
 414                         return $s->iw_url;
 415                 }
 416
 417                 $dbr =& wfGetDB( DB_SLAVE );
 418                 $res = $dbr->select( 'interwiki',
 419                         array( 'iw_url', 'iw_local', 'iw_trans' ),
 420                         array( 'iw_prefix' => $key ), $fname );
 421                 if( !$res ) {
 422                         return '';
 423                 }
 424
 425                 $s = $dbr->fetchObject( $res );
 426                 if( !$s ) {
 427                         # Cache non-existence: create a blank object and save it to memcached
 428                         $s = (object)false;
 429                         $s->iw_url = '';
 430                         $s->iw_local = 0;
 431                         $s->iw_trans = 0;
 432                 }
 433                 $wgMemc->set( $k, $s, $wgInterwikiExpiry );
 434                 Title::$interwikiCache[$k] = $s;
 435
 436                 return $s->iw_url;
 437         }
 438
 439         /**
 440          * Fetch interwiki prefix data from local cache in constant database
 441          *
 442          * More logic is explained in DefaultSettings
 443          *
 444          * @return string URL of interwiki site
 445          * @access public
 446          */
 447         function getInterwikiCached( $key ) {
 448                 global $wgDBname, $wgInterwikiCache, $wgInterwikiScopes, $wgInterwikiFallbackSite;
 449                 static $db, $site;
 450
 451                 if (!$db)
 452                         $db=dba_open($wgInterwikiCache,'r','cdb');
 453                 /* Resolve site name */
 454                 if ($wgInterwikiScopes>=3 and !$site) {
 455                         $site = dba_fetch("__sites:{$wgDBname}", $db);
 456                         if ($site=="")
 457                                 $site = $wgInterwikiFallbackSite;
 458                 }
 459                 $value = dba_fetch("{$wgDBname}:{$key}", $db);
 460                 if ($value=='' and $wgInterwikiScopes>=3) {
 461                         /* try site-level */
 462                         $value = dba_fetch("_{$site}:{$key}", $db);
 463                 }
 464                 if ($value=='' and $wgInterwikiScopes>=2) {
 465                         /* try globals */
 466                         $value = dba_fetch("__global:{$key}", $db);
 467                 }
 468                 if ($value=='undef')
 469                         $value='';
 470                 $s = (object)false;
 471                 $s->iw_url = '';
 472                 $s->iw_local = 0;
 473                 $s->iw_trans = 0;
 474                 if ($value!='') {
 475                         list($local,$url)=explode(' ',$value,2);
 476                         $s->iw_url=$url;
 477                         $s->iw_local=(int)$local;
 478                 }
 479                 Title::$interwikiCache[$wgDBname.':interwiki:'.$key] = $s;
 480                 return $s->iw_url;
 481         }
 482         /**
 483          * Determine whether the object refers to a page within
 484          * this project.
 485          *
 486          * @return bool TRUE if this is an in-project interwiki link
 487          *      or a wikilink, FALSE otherwise
 488          * @access public
 489          */
 490         function isLocal() {
 491                 global $wgDBname;
 492
 493                 if ( $this->mInterwiki != '' ) {
 494                         # Make sure key is loaded into cache
 495                         $this->getInterwikiLink( $this->mInterwiki );
 496                         $k = $wgDBname.':interwiki:' . $this->mInterwiki;
 497                         return (bool)(Title::$interwikiCache[$k]->iw_local);
 498                 } else {
 499                         return true;
 500                 }
 501         }
 502
 503         /**
 504          * Determine whether the object refers to a page within
 505          * this project and is transcludable.
 506          *
 507          * @return bool TRUE if this is transcludable
 508          * @access public
 509          */
 510         function isTrans() {
 511                 global $wgDBname;
 512
 513                 if ($this->mInterwiki == '')
 514                         return false;
 515                 # Make sure key is loaded into cache
 516                 $this->getInterwikiLink( $this->mInterwiki );
 517                 $k = $wgDBname.':interwiki:' . $this->mInterwiki;
 518                 return (bool)(Title::$interwikiCache[$k]->iw_trans);
 519         }
 520
 521         /**
 522          * Update the page_touched field for an array of title objects
 523          * @todo Inefficient unless the IDs are already loaded into the
 524          *      link cache
 525          * @param array $titles an array of Title objects to be touched
 526          * @param string $timestamp the timestamp to use instead of the
 527          *      default current time
 528          * @static
 529          * @access public
 530          */
 531         function touchArray( $titles, $timestamp = '' ) {
 532
 533                 if ( count( $titles ) == 0 ) {
 534                         return;
 535                 }
 536                 $dbw =& wfGetDB( DB_MASTER );
 537                 if ( $timestamp == '' ) {
 538                         $timestamp = $dbw->timestamp();
 539                 }
 540                 /*
 541                 $page = $dbw->tableName( 'page' );
 542                 $sql = "UPDATE $page SET page_touched='{$timestamp}' WHERE page_id IN (";
 543                 $first = true;
 544
 545                 foreach ( $titles as $title ) {
 546                         if ( $wgUseFileCache ) {
 547                                 $cm = new CacheManager($title);
 548                                 @unlink($cm->fileCacheName());
 549                         }
 550
 551                         if ( ! $first ) {
 552                                 $sql .= ',';
 553                         }
 554                         $first = false;
 555                         $sql .= $title->getArticleID();
 556                 }
 557                 $sql .= ')';
 558                 if ( ! $first ) {
 559                         $dbw->query( $sql, 'Title::touchArray' );
 560                 }
 561                 */
 562                 // hack hack hack -- brion 2005-07-11. this was unfriendly to db.
 563                 // do them in small chunks:
 564                 $fname = 'Title::touchArray';
 565                 foreach( $titles as $title ) {
 566                         $dbw->update( 'page',
 567                                 array( 'page_touched' => $timestamp ),
 568                                 array(
 569                                         'page_namespace' => $title->getNamespace(),
 570                                         'page_title'     => $title->getDBkey() ),
 571                                 $fname );
 572                 }
 573         }
 574
 575 #----------------------------------------------------------------------------
 576 #       Other stuff
 577 #----------------------------------------------------------------------------
 578
 579         /** Simple accessors */
 580         /**
 581          * Get the text form (spaces not underscores) of the main part
 582          * @return string
 583          * @access public
 584          */
 585         function getText() { return $this->mTextform; }
 586         /**
 587          * Get the URL-encoded form of the main part
 588          * @return string
 589          * @access public
 590          */
 591         function getPartialURL() { return $this->mUrlform; }
 592         /**
 593          * Get the main part with underscores
 594          * @return string
 595          * @access public
 596          */
 597         function getDBkey() { return $this->mDbkeyform; }
 598         /**
 599          * Get the namespace index, i.e. one of the NS_xxxx constants
 600          * @return int
 601          * @access public
 602          */
 603         function getNamespace() { return $this->mNamespace; }
 604         /**
 605          * Get the namespace text
 606          * @return string
 607          * @access public
 608          */
 609         function getNsText() {
 610                 global $wgContLang;
 611                 return $wgContLang->getNsText( $this->mNamespace );
 612         }
 613         /**
 614          * Get the namespace text of the subject (rather than talk) page
 615          * @return string
 616          * @access public
 617          */
 618         function getSubjectNsText() {
 619                 global $wgContLang;
 620                 return $wgContLang->getNsText( Namespace::getSubject( $this->mNamespace ) );
 621         }
 622
 623         /**
 624          * Get the namespace text of the talk page
 625          * @return string
 626          */
 627         function getTalkNsText() {
 628                 global $wgContLang;
 629                 return( $wgContLang->getNsText( Namespace::getTalk( $this->mNamespace ) ) );
 630         }
 631
 632         /**
 633          * Could this title have a corresponding talk page?
 634          * @return bool
 635          */
 636         function canTalk() {
 637                 return( Namespace::canTalk( $this->mNamespace ) );
 638         }
 639
 640         /**
 641          * Get the interwiki prefix (or null string)
 642          * @return string
 643          * @access public
 644          */
 645         function getInterwiki() { return $this->mInterwiki; }
 646         /**
 647          * Get the Title fragment (i.e. the bit after the #)
 648          * @return string
 649          * @access public
 650          */
 651         function getFragment() { return $this->mFragment; }
 652         /**
 653          * Get the default namespace index, for when there is no namespace
 654          * @return int
 655          * @access public
 656          */
 657         function getDefaultNamespace() { return $this->mDefaultNamespace; }
 658
 659         /**
 660          * Get title for search index
 661          * @return string a stripped-down title string ready for the
 662          *      search index
 663          */
 664         function getIndexTitle() {
 665                 return Title::indexTitle( $this->mNamespace, $this->mTextform );
 666         }
 667
 668         /**
 669          * Get the prefixed database key form
 670          * @return string the prefixed title, with underscores and
 671          *      any interwiki and namespace prefixes
 672          * @access public
 673          */
 674         function getPrefixedDBkey() {
 675                 $s = $this->prefix( $this->mDbkeyform );
 676                 $s = str_replace( ' ', '_', $s );
 677                 return $s;
 678         }
 679
 680         /**
 681          * Get the prefixed title with spaces.
 682          * This is the form usually used for display
 683          * @return string the prefixed title, with spaces
 684          * @access public
 685          */
 686         function getPrefixedText() {
 687                 if ( empty( $this->mPrefixedText ) ) { // FIXME: bad usage of empty() ?
 688                         $s = $this->prefix( $this->mTextform );
 689                         $s = str_replace( '_', ' ', $s );
 690                         $this->mPrefixedText = $s;
 691                 }
 692                 return $this->mPrefixedText;
 693         }
 694
 695         /**
 696          * Get the prefixed title with spaces, plus any fragment
 697          * (part beginning with '#')
 698          * @return string the prefixed title, with spaces and
 699          *      the fragment, including '#'
 700          * @access public
 701          */
 702         function getFullText() {
 703                 $text = $this->getPrefixedText();
 704                 if( '' != $this->mFragment ) {
 705                         $text .= '#' . $this->mFragment;
 706                 }
 707                 return $text;
 708         }
 709
 710         /**
 711          * Get the base name, i.e. the leftmost parts before the /
 712          * @return string Base name
 713          */
 714         function getBaseText() {
 715                 global $wgNamespacesWithSubpages;
 716                 if( isset( $wgNamespacesWithSubpages[ $this->mNamespace ] ) && $wgNamespacesWithSubpages[ $this->mNamespace ] ) {
 717                         $parts = explode( '/', $this->getText() );
 718                         # Don't discard the real title if there's no subpage involved
 719                         if( count( $parts ) > 1 )
 720                                 unset( $parts[ count( $parts ) - 1 ] );
 721                         return implode( '/', $parts );
 722                 } else {
 723                         return $this->getText();
 724                 }
 725         }
 726
 727         /**
 728          * Get the lowest-level subpage name, i.e. the rightmost part after /
 729          * @return string Subpage name
 730          */
 731         function getSubpageText() {
 732                 global $wgNamespacesWithSubpages;
 733                 if( isset( $wgNamespacesWithSubpages[ $this->mNamespace ] ) && $wgNamespacesWithSubpages[ $this->mNamespace ] ) {
 734                         $parts = explode( '/', $this->mTextform );
 735                         return( $parts[ count( $parts ) - 1 ] );
 736                 } else {
 737                         return( $this->mTextform );
 738                 }
 739         }
 740
 741         /**
 742          * Get a URL-encoded form of the subpage text
 743          * @return string URL-encoded subpage name
 744          */
 745         function getSubpageUrlForm() {
 746                 $text = $this->getSubpageText();
 747                 $text = wfUrlencode( str_replace( ' ', '_', $text ) );
 748                 $text = str_replace( '%28', '(', str_replace( '%29', ')', $text ) ); # Clean up the URL; per below, this might not be safe
 749                 return( $text );
 750         }
 751
 752         /**
 753          * Get a URL-encoded title (not an actual URL) including interwiki
 754          * @return string the URL-encoded form
 755          * @access public
 756          */
 757         function getPrefixedURL() {
 758                 $s = $this->prefix( $this->mDbkeyform );
 759                 $s = str_replace( ' ', '_', $s );
 760
 761                 $s = wfUrlencode ( $s ) ;
 762
 763                 # Cleaning up URL to make it look nice -- is this safe?
 764                 $s = str_replace( '%28', '(', $s );
 765                 $s = str_replace( '%29', ')', $s );
 766
 767                 return $s;
 768         }
 769
 770         /**
 771          * Get a real URL referring to this title, with interwiki link and
 772          * fragment
 773          *
 774          * @param string $query an optional query string, not used
 775          *      for interwiki links
 776          * @return string the URL
 777          * @access public
 778          */
 779         function getFullURL( $query = '' ) {
 780                 global $wgContLang, $wgServer, $wgRequest;
 781
 782                 if ( '' == $this->mInterwiki ) {
 783                         $url = $this->getLocalUrl( $query );
 784
 785                         // Ugly quick hack to avoid duplicate prefixes (bug 4571 etc)
 786                         // Correct fix would be to move the prepending elsewhere.
 787                         if ($wgRequest->getVal('action') != 'render') {
 788                                 $url = $wgServer . $url;
 789                         }
 790                 } else {
 791                         $baseUrl = $this->getInterwikiLink( $this->mInterwiki );
 792
 793                         $namespace = $wgContLang->getNsText( $this->mNamespace );
 794                         if ( '' != $namespace ) {
 795                                 # Can this actually happen? Interwikis shouldn't be parsed.
 796                                 $namespace .= ':';
 797                         }
 798                         $url = str_replace( '$1', $namespace . $this->mUrlform, $baseUrl );
 799                         if( $query != '' ) {
 800                                 if( false === strpos( $url, '?' ) ) {
 801                                         $url .= '?';
 802                                 } else {
 803                                         $url .= '&';
 804                                 }
 805                                 $url .= $query;
 806                         }
 807                 }
 808
 809                 # Finally, add the fragment.
 810                 if ( '' != $this->mFragment ) {
 811                         $url .= '#' . $this->mFragment;
 812                 }
 813
 814                 wfRunHooks( 'GetFullURL', array( &$this, &$url, $query ) );
 815                 return $url;
 816         }
 817
 818         /**
 819          * Get a URL with no fragment or server name.  If this page is generated
 820          * with action=render, $wgServer is prepended.
 821          * @param string $query an optional query string; if not specified,
 822          *      $wgArticlePath will be used.
 823          * @return string the URL
 824          * @access public
 825          */
 826         function getLocalURL( $query = '' ) {
 827                 global $wgArticlePath, $wgScript, $wgServer, $wgRequest;
 828
 829                 if ( $this->isExternal() ) {
 830                         $url = $this->getFullURL();
 831                         if ( $query ) {
 832                                 // This is currently only used for edit section links in the
 833                                 // context of interwiki transclusion. In theory we should
 834                                 // append the query to the end of any existing query string,
 835                                 // but interwiki transclusion is already broken in that case.
 836                                 $url .= "?$query";
 837                         }
 838                 } else {
 839                         $dbkey = wfUrlencode( $this->getPrefixedDBkey() );
 840                         if ( $query == '' ) {
 841                                 $url = str_replace( '$1', $dbkey, $wgArticlePath );
 842                         } else {
 843                                 global $wgActionPaths;
 844                                 $url = false;
 845                                 if( !empty( $wgActionPaths ) &&
 846                                         preg_match( '/^(.*&|)action=([^&]*)(&(.*)|)$/', $query, $matches ) )
 847                                 {
 848                                         $action = urldecode( $matches[2] );
 849                                         if( isset( $wgActionPaths[$action] ) ) {
 850                                                 $query = $matches[1];
 851                                                 if( isset( $matches[4] ) ) $query .= $matches[4];
 852                                                 $url = str_replace( '$1', $dbkey, $wgActionPaths[$action] );
 853                                                 if( $query != '' ) $url .= '?' . $query;
 854                                         }
 855                                 }
 856                                 if ( $url === false ) {
 857                                         if ( $query == '-' ) {
 858                                                 $query = '';
 859                                         }
 860                                         $url = "{$wgScript}?title={$dbkey}&{$query}";
 861                                 }
 862                         }
 863
 864                         // FIXME: this causes breakage in various places when we
 865                         // actually expected a local URL and end up with dupe prefixes.
 866                         if ($wgRequest->getVal('action') == 'render') {
 867                                 $url = $wgServer . $url;
 868                         }
 869                 }
 870                 wfRunHooks( 'GetLocalURL', array( &$this, &$url, $query ) );
 871                 return $url;
 872         }
 873
 874         /**
 875          * Get an HTML-escaped version of the URL form, suitable for
 876          * using in a link, without a server name or fragment
 877          * @param string $query an optional query string
 878          * @return string the URL
 879          * @access public
 880          */
 881         function escapeLocalURL( $query = '' ) {
 882                 return htmlspecialchars( $this->getLocalURL( $query ) );
 883         }
 884
 885         /**
 886          * Get an HTML-escaped version of the URL form, suitable for
 887          * using in a link, including the server name and fragment
 888          *
 889          * @return string the URL
 890          * @param string $query an optional query string
 891          * @access public
 892          */
 893         function escapeFullURL( $query = '' ) {
 894                 return htmlspecialchars( $this->getFullURL( $query ) );
 895         }
 896
 897         /**
 898          * Get the URL form for an internal link.
 899          * - Used in various Squid-related code, in case we have a different
 900          * internal hostname for the server from the exposed one.
 901          *
 902          * @param string $query an optional query string
 903          * @return string the URL
 904          * @access public
 905          */
 906         function getInternalURL( $query = '' ) {
 907                 global $wgInternalServer;
 908                 $url = $wgInternalServer . $this->getLocalURL( $query );
 909                 wfRunHooks( 'GetInternalURL', array( &$this, &$url, $query ) );
 910                 return $url;
 911         }
 912
 913         /**
 914          * Get the edit URL for this Title
 915          * @return string the URL, or a null string if this is an
 916          *      interwiki link
 917          * @access public
 918          */
 919         function getEditURL() {
 920                 if ( '' != $this->mInterwiki ) { return ''; }
 921                 $s = $this->getLocalURL( 'action=edit' );
 922
 923                 return $s;
 924         }
 925
 926         /**
 927          * Get the HTML-escaped displayable text form.
 928          * Used for the title field in <a> tags.
 929          * @return string the text, including any prefixes
 930          * @access public
 931          */
 932         function getEscapedText() {
 933                 return htmlspecialchars( $this->getPrefixedText() );
 934         }
 935
 936         /**
 937          * Is this Title interwiki?
 938          * @return boolean
 939          * @access public
 940          */
 941         function isExternal() { return ( '' != $this->mInterwiki ); }
 942
 943         /**
 944          * Is this page "semi-protected" - the *only* protection is autoconfirm?
 945          *
 946          * @param string Action to check (default: edit)
 947          * @return bool
 948          */
 949         function isSemiProtected( $action = 'edit' ) {
 950                 $restrictions = $this->getRestrictions( $action );
 951                 # We do a full compare because this could be an array
 952                 foreach( $restrictions as $restriction ) {
 953                         if( strtolower( $restriction ) != 'autoconfirmed' ) {
 954                                 return( false );
 955                         }
 956                 }
 957                 return( true );
 958         }
 959
 960         /**
 961          * Does the title correspond to a protected article?
 962          * @param string $what the action the page is protected from,
 963          *      by default checks move and edit
 964          * @return boolean
 965          * @access public
 966          */
 967         function isProtected( $action = '' ) {
 968                 global $wgRestrictionLevels;
 969                 if ( -1 == $this->mNamespace ) { return true; }
 970
 971                 if( $action == 'edit' || $action == '' ) {
 972                         $r = $this->getRestrictions( 'edit' );
 973                         foreach( $wgRestrictionLevels as $level ) {
 974                                 if( in_array( $level, $r ) && $level != '' ) {
 975                                         return( true );
 976                                 }
 977                         }
 978                 }
 979
 980                 if( $action == 'move' || $action == '' ) {
 981                         $r = $this->getRestrictions( 'move' );
 982                         foreach( $wgRestrictionLevels as $level ) {
 983                                 if( in_array( $level, $r ) && $level != '' ) {
 984                                         return( true );
 985                                 }
 986                         }
 987                 }
 988
 989                 return false;
 990         }
 991
 992         /**
 993          * Is $wgUser is watching this page?
 994          * @return boolean
 995          * @access public
 996          */
 997         function userIsWatching() {
 998                 global $wgUser;
 999
1000                 if ( is_null( $this->mWatched ) ) {
1001                         if ( -1 == $this->mNamespace || 0 == $wgUser->getID()) {
1002                                 $this->mWatched = false;
1003                         } else {
1004                                 $this->mWatched = $wgUser->isWatched( $this );
1005                         }
1006                 }
1007                 return $this->mWatched;
1008         }
1009
1010         /**
1011          * Can $wgUser perform $action this page?
1012          * @param string $action action that permission needs to be checked for
1013          * @return boolean
1014          * @private
1015          */
1016         function userCan($action) {
1017                 $fname = 'Title::userCan';
1018                 wfProfileIn( $fname );
1019
1020                 global $wgUser;
1021
1022                 $result = null;
1023                 wfRunHooks( 'userCan', array( &$this, &$wgUser, $action, &$result ) );
1024                 if ( $result !== null ) {
1025                         wfProfileOut( $fname );
1026                         return $result;
1027                 }
1028
1029                 if( NS_SPECIAL == $this->mNamespace ) {
1030                         wfProfileOut( $fname );
1031                         return false;
1032                 }
1033                 // XXX: This is the code that prevents unprotecting a page in NS_MEDIAWIKI
1034                 // from taking effect -ævar
1035                 if( NS_MEDIAWIKI == $this->mNamespace &&
1036                     !$wgUser->isAllowed('editinterface') ) {
1037                         wfProfileOut( $fname );
1038                         return false;
1039                 }
1040
1041                 if( $this->mDbkeyform == '_' ) {
1042                         # FIXME: Is this necessary? Shouldn't be allowed anyway...
1043                         wfProfileOut( $fname );
1044                         return false;
1045                 }
1046
1047                 # protect css/js subpages of user pages
1048                 # XXX: this might be better using restrictions
1049                 # XXX: Find a way to work around the php bug that prevents using $this->userCanEditCssJsSubpage() from working
1050                 if( NS_USER == $this->mNamespace
1051                         && preg_match("/\\.(css|js)$/", $this->mTextform )
1052                         && !$wgUser->isAllowed('editinterface')
1053                         && !preg_match('/^'.preg_quote($wgUser->getName(), '/').'\//', $this->mTextform) ) {
1054                         wfProfileOut( $fname );
1055                         return false;
1056                 }
1057
1058                 foreach( $this->getRestrictions($action) as $right ) {
1059                         // Backwards compatibility, rewrite sysop -> protect
1060                         if ( $right == 'sysop' ) {
1061                                 $right = 'protect';
1062                         }
1063                         if( '' != $right && !$wgUser->isAllowed( $right ) ) {
1064                                 wfProfileOut( $fname );
1065                                 return false;
1066                         }
1067                 }
1068
1069                 if( $action == 'move' &&
1070                         !( $this->isMovable() && $wgUser->isAllowed( 'move' ) ) ) {
1071                         wfProfileOut( $fname );
1072                         return false;
1073                 }
1074
1075                 if( $action == 'create' ) {
1076                         if( (  $this->isTalkPage() && !$wgUser->isAllowed( 'createtalk' ) ) ||
1077                                 ( !$this->isTalkPage() && !$wgUser->isAllowed( 'createpage' ) ) ) {
1078                                 wfProfileOut( $fname );
1079                                 return false;
1080                         }
1081                 }
1082
1083                 wfProfileOut( $fname );
1084                 return true;
1085         }
1086
1087         /**
1088          * Can $wgUser edit this page?
1089          * @return boolean
1090          * @access public
1091          */
1092         function userCanEdit() {
1093                 return $this->userCan('edit');
1094         }
1095
1096         /**
1097          * Can $wgUser create this page?
1098          * @return boolean
1099          * @access public
1100          */
1101         function userCanCreate() {
1102                 return $this->userCan('create');
1103         }
1104
1105         /**
1106          * Can $wgUser move this page?
1107          * @return boolean
1108          * @access public
1109          */
1110         function userCanMove() {
1111                 return $this->userCan('move');
1112         }
1113
1114         /**
1115          * Would anybody with sufficient privileges be able to move this page?
1116          * Some pages just aren't movable.
1117          *
1118          * @return boolean
1119          * @access public
1120          */
1121         function isMovable() {
1122                 return Namespace::isMovable( $this->getNamespace() )
1123                         && $this->getInterwiki() == '';
1124         }
1125
1126         /**
1127          * Can $wgUser read this page?
1128          * @return boolean
1129          * @access public
1130          */
1131         function userCanRead() {
1132                 global $wgUser;
1133
1134                 $result = null;
1135                 wfRunHooks( 'userCan', array( &$this, &$wgUser, 'read', &$result ) );
1136                 if ( $result !== null ) {
1137                         return $result;
1138                 }
1139
1140                 if( $wgUser->isAllowed('read') ) {
1141                         return true;
1142                 } else {
1143                         global $wgWhitelistRead;
1144
1145                         /** If anon users can create an account,
1146                             they need to reach the login page first! */
1147                         if( $wgUser->isAllowed( 'createaccount' )
1148                             && $this->getNamespace() == NS_SPECIAL
1149                             && $this->getText() == 'Userlogin' ) {
1150                                 return true;
1151                         }
1152
1153                         /** some pages are explicitly allowed */
1154                         $name = $this->getPrefixedText();
1155                         if( $wgWhitelistRead && in_array( $name, $wgWhitelistRead ) ) {
1156                                 return true;
1157                         }
1158
1159                         # Compatibility with old settings
1160                         if( $wgWhitelistRead && $this->getNamespace() == NS_MAIN ) {
1161                                 if( in_array( ':' . $name, $wgWhitelistRead ) ) {
1162                                         return true;
1163                                 }
1164                         }
1165                 }
1166                 return false;
1167         }
1168
1169         /**
1170          * Is this a talk page of some sort?
1171          * @return bool
1172          * @access public
1173          */
1174         function isTalkPage() {
1175                 return Namespace::isTalk( $this->getNamespace() );
1176         }
1177
1178         /**
1179          * Is this a .css or .js subpage of a user page?
1180          * @return bool
1181          * @access public
1182          */
1183         function isCssJsSubpage() {
1184                 return ( NS_USER == $this->mNamespace and preg_match("/\\.(css|js)$/", $this->mTextform ) );
1185         }
1186         /**
1187          * Is this a *valid* .css or .js subpage of a user page?
1188          * Check that the corresponding skin exists
1189          */
1190         function isValidCssJsSubpage() {
1191                 if ( $this->isCssJsSubpage() ) {
1192                         $skinNames = Skin::getSkinNames();
1193                         return array_key_exists( $this->getSkinFromCssJsSubpage(), $skinNames );
1194                 } else {
1195                         return false;
1196                 }
1197         }
1198         /**
1199          * Trim down a .css or .js subpage title to get the corresponding skin name
1200          */
1201         function getSkinFromCssJsSubpage() {
1202                 $subpage = explode( '/', $this->mTextform );
1203                 $subpage = $subpage[ count( $subpage ) - 1 ];
1204                 return( str_replace( array( '.css', '.js' ), array( '', '' ), $subpage ) );
1205         }
1206         /**
1207          * Is this a .css subpage of a user page?
1208          * @return bool
1209          * @access public
1210          */
1211         function isCssSubpage() {
1212                 return ( NS_USER == $this->mNamespace and preg_match("/\\.css$/", $this->mTextform ) );
1213         }
1214         /**
1215          * Is this a .js subpage of a user page?
1216          * @return bool
1217          * @access public
1218          */
1219         function isJsSubpage() {
1220                 return ( NS_USER == $this->mNamespace and preg_match("/\\.js$/", $this->mTextform ) );
1221         }
1222         /**
1223          * Protect css/js subpages of user pages: can $wgUser edit
1224          * this page?
1225          *
1226          * @return boolean
1227          * @todo XXX: this might be better using restrictions
1228          * @access public
1229          */
1230         function userCanEditCssJsSubpage() {
1231                 global $wgUser;
1232                 return ( $wgUser->isAllowed('editinterface') or preg_match('/^'.preg_quote($wgUser->getName(), '/').'\//', $this->mTextform) );
1233         }
1234
1235         /**
1236          * Loads a string into mRestrictions array
1237          * @param string $res restrictions in string format
1238          * @access public
1239          */
1240         function loadRestrictions( $res ) {
1241                 foreach( explode( ':', trim( $res ) ) as $restrict ) {
1242                         $temp = explode( '=', trim( $restrict ) );
1243                         if(count($temp) == 1) {
1244                                 // old format should be treated as edit/move restriction
1245                                 $this->mRestrictions["edit"] = explode( ',', trim( $temp[0] ) );
1246                                 $this->mRestrictions["move"] = explode( ',', trim( $temp[0] ) );
1247                         } else {
1248                                 $this->mRestrictions[$temp[0]] = explode( ',', trim( $temp[1] ) );
1249                         }
1250                 }
1251                 $this->mRestrictionsLoaded = true;
1252         }
1253
1254         /**
1255          * Accessor/initialisation for mRestrictions
1256          * @param string $action action that permission needs to be checked for
1257          * @return array the array of groups allowed to edit this article
1258          * @access public
1259          */
1260         function getRestrictions($action) {
1261                 $id = $this->getArticleID();
1262                 if ( 0 == $id ) { return array(); }
1263
1264                 if ( ! $this->mRestrictionsLoaded ) {
1265                         $dbr =& wfGetDB( DB_SLAVE );
1266                         $res = $dbr->selectField( 'page', 'page_restrictions', 'page_id='.$id );
1267                         $this->loadRestrictions( $res );
1268                 }
1269                 if( isset( $this->mRestrictions[$action] ) ) {
1270                         return $this->mRestrictions[$action];
1271                 }
1272                 return array();
1273         }
1274
1275         /**
1276          * Is there a version of this page in the deletion archive?
1277          * @return int the number of archived revisions
1278          * @access public
1279          */
1280         function isDeleted() {
1281                 $fname = 'Title::isDeleted';
1282                 if ( $this->getNamespace() < 0 ) {
1283                         $n = 0;
1284                 } else {
1285                         $dbr =& wfGetDB( DB_SLAVE );
1286                         $n = $dbr->selectField( 'archive', 'COUNT(*)', array( 'ar_namespace' => $this->getNamespace(),
1287                                 'ar_title' => $this->getDBkey() ), $fname );
1288                         if( $this->getNamespace() == NS_IMAGE ) {
1289                                 $n += $dbr->selectField( 'filearchive', 'COUNT(*)',
1290                                         array( 'fa_name' => $this->getDBkey() ), $fname );
1291                         }
1292                 }
1293                 return (int)$n;
1294         }
1295
1296         /**
1297          * Get the article ID for this Title from the link cache,
1298          * adding it if necessary
1299          * @param int $flags a bit field; may be GAID_FOR_UPDATE to select
1300          *      for update
1301          * @return int the ID
1302          * @access public
1303          */
1304         function getArticleID( $flags = 0 ) {
1305                 $linkCache =& LinkCache::singleton();
1306                 if ( $flags & GAID_FOR_UPDATE ) {
1307                         $oldUpdate = $linkCache->forUpdate( true );
1308                         $this->mArticleID = $linkCache->addLinkObj( $this );
1309                         $linkCache->forUpdate( $oldUpdate );
1310                 } else {
1311                         if ( -1 == $this->mArticleID ) {
1312                                 $this->mArticleID = $linkCache->addLinkObj( $this );
1313                         }
1314                 }
1315                 return $this->mArticleID;
1316         }
1317
1318         function getLatestRevID() {
1319                 if ($this->mLatestID !== false)
1320                         return $this->mLatestID;
1321
1322                 $db =& wfGetDB(DB_SLAVE);
1323                 return $this->mLatestID = $db->selectField( 'revision',
1324                         "max(rev_id)",
1325                         array('rev_page' => $this->getArticleID()),
1326                         'Title::getLatestRevID' );
1327         }
1328
1329         /**
1330          * This clears some fields in this object, and clears any associated
1331          * keys in the "bad links" section of the link cache.
1332          *
1333          * - This is called from Article::insertNewArticle() to allow
1334          * loading of the new page_id. It's also called from
1335          * Article::doDeleteArticle()
1336          *
1337          * @param int $newid the new Article ID
1338          * @access public
1339          */
1340         function resetArticleID( $newid ) {
1341                 $linkCache =& LinkCache::singleton();
1342                 $linkCache->clearBadLink( $this->getPrefixedDBkey() );
1343
1344                 if ( 0 == $newid ) { $this->mArticleID = -1; }
1345                 else { $this->mArticleID = $newid; }
1346                 $this->mRestrictionsLoaded = false;
1347                 $this->mRestrictions = array();
1348         }
1349
1350         /**
1351          * Updates page_touched for this page; called from LinksUpdate.php
1352          * @return bool true if the update succeded
1353          * @access public
1354          */
1355         function invalidateCache() {
1356                 global $wgUseFileCache;
1357
1358                 if ( wfReadOnly() ) {
1359                         return;
1360                 }
1361
1362                 $dbw =& wfGetDB( DB_MASTER );
1363                 $success = $dbw->update( 'page',
1364                         array( /* SET */
1365                                 'page_touched' => $dbw->timestamp()
1366                         ), array( /* WHERE */
1367                                 'page_namespace' => $this->getNamespace() ,
1368                                 'page_title' => $this->getDBkey()
1369                         ), 'Title::invalidateCache'
1370                 );
1371
1372                 if ($wgUseFileCache) {
1373                         $cache = new CacheManager($this);
1374                         @unlink($cache->fileCacheName());
1375                 }
1376
1377                 return $success;
1378         }
1379
1380         /**
1381          * Prefix some arbitrary text with the namespace or interwiki prefix
1382          * of this object
1383          *
1384          * @param string $name the text
1385          * @return string the prefixed text
1386          * @private
1387          */
1388         /* private */ function prefix( $name ) {
1389                 global $wgContLang;
1390
1391                 $p = '';
1392                 if ( '' != $this->mInterwiki ) {
1393                         $p = $this->mInterwiki . ':';
1394                 }
1395                 if ( 0 != $this->mNamespace ) {
1396                         $p .= $wgContLang->getNsText( $this->mNamespace ) . ':';
1397                 }
1398                 return $p . $name;
1399         }
1400
1401         /**
1402          * Secure and split - main initialisation function for this object
1403          *
1404          * Assumes that mDbkeyform has been set, and is urldecoded
1405          * and uses underscores, but not otherwise munged.  This function
1406          * removes illegal characters, splits off the interwiki and
1407          * namespace prefixes, sets the other forms, and canonicalizes
1408          * everything.
1409          * @return bool true on success
1410          * @private
1411          */
1412         /* private */ function secureAndSplit() {
1413                 global $wgContLang, $wgLocalInterwiki, $wgCapitalLinks;
1414                 $fname = 'Title::secureAndSplit';
1415
1416                 # Initialisation
1417                 static $rxTc = false;
1418                 if( !$rxTc ) {
1419                         # % is needed as well
1420                         $rxTc = '/[^' . Title::legalChars() . ']|%[0-9A-Fa-f]{2}/S';
1421                 }
1422
1423                 $this->mInterwiki = $this->mFragment = '';
1424                 $this->mNamespace = $this->mDefaultNamespace; # Usually NS_MAIN
1425
1426                 # Clean up whitespace
1427                 #
1428                 $t = preg_replace( '/[ _]+/', '_', $this->mDbkeyform );
1429                 $t = trim( $t, '_' );
1430
1431                 if ( '' == $t ) {
1432                         return false;
1433                 }
1434
1435                 if( false !== strpos( $t, UTF8_REPLACEMENT ) ) {
1436                         # Contained illegal UTF-8 sequences or forbidden Unicode chars.
1437                         return false;
1438                 }
1439
1440                 $this->mDbkeyform = $t;
1441
1442                 # Initial colon indicates main namespace rather than specified default
1443                 # but should not create invalid {ns,title} pairs such as {0,Project:Foo}
1444                 if ( ':' == $t{0} ) {
1445                         $this->mNamespace = NS_MAIN;
1446                         $t = substr( $t, 1 ); # remove the colon but continue processing
1447                 }
1448
1449                 # Namespace or interwiki prefix
1450                 $firstPass = true;
1451                 do {
1452                         if ( preg_match( "/^(.+?)_*:_*(.*)$/S", $t, $m ) ) {
1453                                 $p = $m[1];
1454                                 $lowerNs = strtolower( $p );
1455                                 if ( $ns = Namespace::getCanonicalIndex( $lowerNs ) ) {
1456                                         # Canonical namespace
1457                                         $t = $m[2];
1458                                         $this->mNamespace = $ns;
1459                                 } elseif ( $ns = $wgContLang->getNsIndex( $lowerNs )) {
1460                                         # Ordinary namespace
1461                                         $t = $m[2];
1462                                         $this->mNamespace = $ns;
1463                                 } elseif( $this->getInterwikiLink( $p ) ) {
1464                                         if( !$firstPass ) {
1465                                                 # Can't make a local interwiki link to an interwiki link.
1466                                                 # That's just crazy!
1467                                                 return false;
1468                                         }
1469
1470                                         # Interwiki link
1471                                         $t = $m[2];
1472                                         $this->mInterwiki = strtolower( $p );
1473
1474                                         # Redundant interwiki prefix to the local wiki
1475                                         if ( 0 == strcasecmp( $this->mInterwiki, $wgLocalInterwiki ) ) {
1476                                                 if( $t == '' ) {
1477                                                         # Can't have an empty self-link
1478                                                         return false;
1479                                                 }
1480                                                 $this->mInterwiki = '';
1481                                                 $firstPass = false;
1482                                                 # Do another namespace split...
1483                                                 continue;
1484                                         }
1485
1486                                         # If there's an initial colon after the interwiki, that also
1487                                         # resets the default namespace
1488                                         if ( $t !== '' && $t[0] == ':' ) {
1489                                                 $this->mNamespace = NS_MAIN;
1490                                                 $t = substr( $t, 1 );
1491                                         }
1492                                 }
1493                                 # If there's no recognized interwiki or namespace,
1494                                 # then let the colon expression be part of the title.
1495                         }
1496                         break;
1497                 } while( true );
1498                 $r = $t;
1499
1500                 # We already know that some pages won't be in the database!
1501                 #
1502                 if ( '' != $this->mInterwiki || -1 == $this->mNamespace ) {
1503                         $this->mArticleID = 0;
1504                 }
1505                 $f = strstr( $r, '#' );
1506                 if ( false !== $f ) {
1507                         $this->mFragment = substr( $f, 1 );
1508                         $r = substr( $r, 0, strlen( $r ) - strlen( $f ) );
1509                         # remove whitespace again: prevents "Foo_bar_#"
1510                         # becoming "Foo_bar_"
1511                         $r = preg_replace( '/_*$/', '', $r );
1512                 }
1513
1514                 # Reject illegal characters.
1515                 #
1516                 if( preg_match( $rxTc, $r ) ) {
1517                         return false;
1518                 }
1519
1520                 /**
1521                  * Pages with "/./" or "/../" appearing in the URLs will
1522                  * often be unreachable due to the way web browsers deal
1523                  * with 'relative' URLs. Forbid them explicitly.
1524                  */
1525                 if ( strpos( $r, '.' ) !== false &&
1526                      ( $r === '.' || $r === '..' ||
1527                        strpos( $r, './' ) === 0  ||
1528                        strpos( $r, '../' ) === 0 ||
1529                        strpos( $r, '/./' ) !== false ||
1530                        strpos( $r, '/../' ) !== false ) )
1531                 {
1532                         return false;
1533                 }
1534
1535                 # We shouldn't need to query the DB for the size.
1536                 #$maxSize = $dbr->textFieldSize( 'page', 'page_title' );
1537                 if ( strlen( $r ) > 255 ) {
1538                         return false;
1539                 }
1540
1541                 /**
1542                  * Normally, all wiki links are forced to have
1543                  * an initial capital letter so [[foo]] and [[Foo]]
1544                  * point to the same place.
1545                  *
1546                  * Don't force it for interwikis, since the other
1547                  * site might be case-sensitive.
1548                  */
1549                 if( $wgCapitalLinks && $this->mInterwiki == '') {
1550                         $t = $wgContLang->ucfirst( $r );
1551                 } else {
1552                         $t = $r;
1553                 }
1554
1555                 /**
1556                  * Can't make a link to a namespace alone...
1557                  * "empty" local links can only be self-links
1558                  * with a fragment identifier.
1559                  */
1560                 if( $t == '' &&
1561                         $this->mInterwiki == '' &&
1562                         $this->mNamespace != NS_MAIN ) {
1563                         return false;
1564                 }
1565
1566                 // Any remaining initial :s are illegal.
1567                 if ( $t !== '' && ':' == $t{0} ) {
1568                         return false;
1569                 }
1570
1571                 # Fill fields
1572                 $this->mDbkeyform = $t;
1573                 $this->mUrlform = wfUrlencode( $t );
1574
1575                 $this->mTextform = str_replace( '_', ' ', $t );
1576
1577                 return true;
1578         }
1579
1580         /**
1581          * Get a Title object associated with the talk page of this article
1582          * @return Title the object for the talk page
1583          * @access public
1584          */
1585         function getTalkPage() {
1586                 return Title::makeTitle( Namespace::getTalk( $this->getNamespace() ), $this->getDBkey() );
1587         }
1588
1589         /**
1590          * Get a title object associated with the subject page of this
1591          * talk page
1592          *
1593          * @return Title the object for the subject page
1594          * @access public
1595          */
1596         function getSubjectPage() {
1597                 return Title::makeTitle( Namespace::getSubject( $this->getNamespace() ), $this->getDBkey() );
1598         }
1599
1600         /**
1601          * Get an array of Title objects linking to this Title
1602          * Also stores the IDs in the link cache.
1603          *
1604          * WARNING: do not use this function on arbitrary user-supplied titles!
1605          * On heavily-used templates it will max out the memory.
1606          *
1607          * @param string $options may be FOR UPDATE
1608          * @return array the Title objects linking here
1609          * @access public
1610          */
1611         function getLinksTo( $options = '', $table = 'pagelinks', $prefix = 'pl' ) {
1612                 $linkCache =& LinkCache::singleton();
1613                 $id = $this->getArticleID();
1614
1615                 if ( $options ) {
1616                         $db =& wfGetDB( DB_MASTER );
1617                 } else {
1618                         $db =& wfGetDB( DB_SLAVE );
1619                 }
1620
1621                 $res = $db->select( array( 'page', $table ),
1622                         array( 'page_namespace', 'page_title', 'page_id' ),
1623                         array(
1624                                 "{$prefix}_from=page_id",
1625                                 "{$prefix}_namespace" => $this->getNamespace(),
1626                                 "{$prefix}_title"     => $this->getDbKey() ),
1627                         'Title::getLinksTo',
1628                         $options );
1629
1630                 $retVal = array();
1631                 if ( $db->numRows( $res ) ) {
1632                         while ( $row = $db->fetchObject( $res ) ) {
1633                                 if ( $titleObj = Title::makeTitle( $row->page_namespace, $row->page_title ) ) {
1634                                         $linkCache->addGoodLinkObj( $row->page_id, $titleObj );
1635                                         $retVal[] = $titleObj;
1636                                 }
1637                         }
1638                 }
1639                 $db->freeResult( $res );
1640                 return $retVal;
1641         }
1642
1643         /**
1644          * Get an array of Title objects using this Title as a template
1645          * Also stores the IDs in the link cache.
1646          *
1647          * WARNING: do not use this function on arbitrary user-supplied titles!
1648          * On heavily-used templates it will max out the memory.
1649          *
1650          * @param string $options may be FOR UPDATE
1651          * @return array the Title objects linking here
1652          * @access public
1653          */
1654         function getTemplateLinksTo( $options = '' ) {
1655                 return $this->getLinksTo( $options, 'templatelinks', 'tl' );
1656         }
1657
1658         /**
1659          * Get an array of Title objects referring to non-existent articles linked from this page
1660          *
1661          * @param string $options may be FOR UPDATE
1662          * @return array the Title objects
1663          * @access public
1664          */
1665         function getBrokenLinksFrom( $options = '' ) {
1666                 if ( $options ) {
1667                         $db =& wfGetDB( DB_MASTER );
1668                 } else {
1669                         $db =& wfGetDB( DB_SLAVE );
1670                 }
1671
1672                 $res = $db->safeQuery(
1673                           "SELECT pl_namespace, pl_title
1674                              FROM !
1675                         LEFT JOIN !
1676                                ON pl_namespace=page_namespace
1677                               AND pl_title=page_title
1678                             WHERE pl_from=?
1679                               AND page_namespace IS NULL
1680                                   !",
1681                         $db->tableName( 'pagelinks' ),
1682                         $db->tableName( 'page' ),
1683                         $this->getArticleId(),
1684                         $options );
1685
1686                 $retVal = array();
1687                 if ( $db->numRows( $res ) ) {
1688                         while ( $row = $db->fetchObject( $res ) ) {
1689                                 $retVal[] = Title::makeTitle( $row->pl_namespace, $row->pl_title );
1690                         }
1691                 }
1692                 $db->freeResult( $res );
1693                 return $retVal;
1694         }
1695
1696
1697         /**
1698          * Get a list of URLs to purge from the Squid cache when this
1699          * page changes
1700          *
1701          * @return array the URLs
1702          * @access public
1703          */
1704         function getSquidURLs() {
1705                 return array(
1706                         $this->getInternalURL(),
1707                         $this->getInternalURL( 'action=history' )
1708                 );
1709         }
1710
1711         function purgeSquid() {
1712                 global $wgUseSquid;
1713                 if ( $wgUseSquid ) {
1714                         $urls = $this->getSquidURLs();
1715                         $u = new SquidUpdate( $urls );
1716                         $u->doUpdate();
1717                 }
1718         }
1719
1720         /**
1721          * Move this page without authentication
1722          * @param Title &$nt the new page Title
1723          * @access public
1724          */
1725         function moveNoAuth( &$nt ) {
1726                 return $this->moveTo( $nt, false );
1727         }
1728
1729         /**
1730          * Check whether a given move operation would be valid.
1731          * Returns true if ok, or a message key string for an error message
1732          * if invalid. (Scarrrrry ugly interface this.)
1733          * @param Title &$nt the new title
1734          * @param bool $auth indicates whether $wgUser's permissions
1735          *      should be checked
1736          * @return mixed true on success, message name on failure
1737          * @access public
1738          */
1739         function isValidMoveOperation( &$nt, $auth = true ) {
1740                 if( !$this or !$nt ) {
1741                         return 'badtitletext';
1742                 }
1743                 if( $this->equals( $nt ) ) {
1744                         return 'selfmove';
1745                 }
1746                 if( !$this->isMovable() || !$nt->isMovable() ) {
1747                         return 'immobile_namespace';
1748                 }
1749
1750                 $oldid = $this->getArticleID();
1751                 $newid = $nt->getArticleID();
1752
1753                 if ( strlen( $nt->getDBkey() ) < 1 ) {
1754                         return 'articleexists';
1755                 }
1756                 if ( ( '' == $this->getDBkey() ) ||
1757                          ( !$oldid ) ||
1758                      ( '' == $nt->getDBkey() ) ) {
1759                         return 'badarticleerror';
1760                 }
1761
1762                 if ( $auth && (
1763                                 !$this->userCanEdit() || !$nt->userCanEdit() ||
1764                                 !$this->userCanMove() || !$nt->userCanMove() ) ) {
1765                         return 'protectedpage';
1766                 }
1767
1768                 # The move is allowed only if (1) the target doesn't exist, or
1769                 # (2) the target is a redirect to the source, and has no history
1770                 # (so we can undo bad moves right after they're done).
1771
1772                 if ( 0 != $newid ) { # Target exists; check for validity
1773                         if ( ! $this->isValidMoveTarget( $nt ) ) {
1774                                 return 'articleexists';
1775                         }
1776                 }
1777                 return true;
1778         }
1779
1780         /**
1781          * Move a title to a new location
1782          * @param Title &$nt the new title
1783          * @param bool $auth indicates whether $wgUser's permissions
1784          *      should be checked
1785          * @return mixed true on success, message name on failure
1786          * @access public
1787          */
1788         function moveTo( &$nt, $auth = true, $reason = '' ) {
1789                 $err = $this->isValidMoveOperation( $nt, $auth );
1790                 if( is_string( $err ) ) {
1791                         return $err;
1792                 }
1793
1794                 $pageid = $this->getArticleID();
1795                 if( $nt->exists() ) {
1796                         $this->moveOverExistingRedirect( $nt, $reason );
1797                         $pageCountChange = 0;
1798                 } else { # Target didn't exist, do normal move.
1799                         $this->moveToNewTitle( $nt, $reason );
1800                         $pageCountChange = 1;
1801                 }
1802                 $redirid = $this->getArticleID();
1803
1804                 # Fixing category links (those without piped 'alternate' names) to be sorted under the new title
1805                 $dbw =& wfGetDB( DB_MASTER );
1806                 $categorylinks = $dbw->tableName( 'categorylinks' );
1807                 $sql = "UPDATE $categorylinks SET cl_sortkey=" . $dbw->addQuotes( $nt->getPrefixedText() ) .
1808                         " WHERE cl_from=" . $dbw->addQuotes( $pageid ) .
1809                         " AND cl_sortkey=" . $dbw->addQuotes( $this->getPrefixedText() );
1810                 $dbw->query( $sql, 'SpecialMovepage::doSubmit' );
1811
1812                 # Update watchlists
1813
1814                 $oldnamespace = $this->getNamespace() & ~1;
1815                 $newnamespace = $nt->getNamespace() & ~1;
1816                 $oldtitle = $this->getDBkey();
1817                 $newtitle = $nt->getDBkey();
1818
1819                 if( $oldnamespace != $newnamespace || $oldtitle != $newtitle ) {
1820                         WatchedItem::duplicateEntries( $this, $nt );
1821                 }
1822
1823                 # Update search engine
1824                 $u = new SearchUpdate( $pageid, $nt->getPrefixedDBkey() );
1825                 $u->doUpdate();
1826                 $u = new SearchUpdate( $redirid, $this->getPrefixedDBkey(), '' );
1827                 $u->doUpdate();
1828
1829                 # Update site_stats
1830                 if ( $this->getNamespace() == NS_MAIN and $nt->getNamespace() != NS_MAIN ) {
1831                         # Moved out of main namespace
1832                         # not viewed, edited, removing
1833                         $u = new SiteStatsUpdate( 0, 1, -1, $pageCountChange);
1834                 } elseif ( $this->getNamespace() != NS_MAIN and $nt->getNamespace() == NS_MAIN ) {
1835                         # Moved into main namespace
1836                         # not viewed, edited, adding
1837                         $u = new SiteStatsUpdate( 0, 1, +1, $pageCountChange );
1838                 } elseif ( $pageCountChange ) {
1839                         # Added redirect
1840                         $u = new SiteStatsUpdate( 0, 0, 0, 1 );
1841                 } else{
1842                         $u = false;
1843                 }
1844                 if ( $u ) {
1845                         $u->doUpdate();
1846                 }
1847
1848                 global $wgUser;
1849                 wfRunHooks( 'TitleMoveComplete', array( &$this, &$nt, &$wgUser, $pageid, $redirid ) );
1850                 return true;
1851         }
1852
1853         /**
1854          * Move page to a title which is at present a redirect to the
1855          * source page
1856          *
1857          * @param Title &$nt the page to move to, which should currently
1858          *      be a redirect
1859          * @private
1860          */
1861         function moveOverExistingRedirect( &$nt, $reason = '' ) {
1862                 global $wgUseSquid;
1863                 $fname = 'Title::moveOverExistingRedirect';
1864                 $comment = wfMsgForContent( '1movedto2', $this->getPrefixedText(), $nt->getPrefixedText() );
1865
1866                 if ( $reason ) {
1867                         $comment .= ": $reason";
1868                 }
1869
1870                 $now = wfTimestampNow();
1871                 $rand = wfRandom();
1872                 $newid = $nt->getArticleID();
1873                 $oldid = $this->getArticleID();
1874                 $dbw =& wfGetDB( DB_MASTER );
1875                 $linkCache =& LinkCache::singleton();
1876
1877                 # Delete the old redirect. We don't save it to history since
1878                 # by definition if we've got here it's rather uninteresting.
1879                 # We have to remove it so that the next step doesn't trigger
1880                 # a conflict on the unique namespace+title index...
1881                 $dbw->delete( 'page', array( 'page_id' => $newid ), $fname );
1882
1883                 # Save a null revision in the page's history notifying of the move
1884                 $nullRevision = Revision::newNullRevision( $dbw, $oldid, $comment, true );
1885                 $nullRevId = $nullRevision->insertOn( $dbw );
1886
1887                 # Change the name of the target page:
1888                 $dbw->update( 'page',
1889                         /* SET */ array(
1890                                 'page_touched'   => $dbw->timestamp($now),
1891                                 'page_namespace' => $nt->getNamespace(),
1892                                 'page_title'     => $nt->getDBkey(),
1893                                 'page_latest'    => $nullRevId,
1894                         ),
1895                         /* WHERE */ array( 'page_id' => $oldid ),
1896                         $fname
1897                 );
1898                 $linkCache->clearLink( $nt->getPrefixedDBkey() );
1899
1900                 # Recreate the redirect, this time in the other direction.
1901                 $mwRedir = MagicWord::get( 'redirect' );
1902                 $redirectText = $mwRedir->getSynonym( 0 ) . ' [[' . $nt->getPrefixedText() . "]]\n";
1903                 $redirectArticle = new Article( $this );
1904                 $newid = $redirectArticle->insertOn( $dbw );
1905                 $redirectRevision = new Revision( array(
1906                         'page'    => $newid,
1907                         'comment' => $comment,
1908                         'text'    => $redirectText ) );
1909                 $revid = $redirectRevision->insertOn( $dbw );
1910                 $redirectArticle->updateRevisionOn( $dbw, $redirectRevision, 0 );
1911                 $linkCache->clearLink( $this->getPrefixedDBkey() );
1912
1913                 # Log the move
1914                 $log = new LogPage( 'move' );
1915                 $log->addEntry( 'move_redir', $this, $reason, array( 1 => $nt->getPrefixedText() ) );
1916
1917                 # Now, we record the link from the redirect to the new title.
1918                 # It should have no other outgoing links...
1919                 $dbw->delete( 'pagelinks', array( 'pl_from' => $newid ), $fname );
1920                 $dbw->insert( 'pagelinks',
1921                         array(
1922                                 'pl_from'      => $newid,
1923                                 'pl_namespace' => $nt->getNamespace(),
1924                                 'pl_title'     => $nt->getDbKey() ),
1925                         $fname );
1926
1927                 # Purge squid
1928                 if ( $wgUseSquid ) {
1929                         $urls = array_merge( $nt->getSquidURLs(), $this->getSquidURLs() );
1930                         $u = new SquidUpdate( $urls );
1931                         $u->doUpdate();
1932                 }
1933         }
1934
1935         /**
1936          * Move page to non-existing title.
1937          * @param Title &$nt the new Title
1938          * @private
1939          */
1940         function moveToNewTitle( &$nt, $reason = '' ) {
1941                 global $wgUseSquid;
1942                 $fname = 'MovePageForm::moveToNewTitle';
1943                 $comment = wfMsgForContent( '1movedto2', $this->getPrefixedText(), $nt->getPrefixedText() );
1944                 if ( $reason ) {
1945                         $comment .= ": $reason";
1946                 }
1947
1948                 $newid = $nt->getArticleID();
1949                 $oldid = $this->getArticleID();
1950                 $dbw =& wfGetDB( DB_MASTER );
1951                 $now = $dbw->timestamp();
1952                 $rand = wfRandom();
1953                 $linkCache =& LinkCache::singleton();
1954
1955                 # Save a null revision in the page's history notifying of the move
1956                 $nullRevision = Revision::newNullRevision( $dbw, $oldid, $comment, true );
1957                 $nullRevId = $nullRevision->insertOn( $dbw );
1958
1959                 # Rename cur entry
1960                 $dbw->update( 'page',
1961                         /* SET */ array(
1962                                 'page_touched'   => $now,
1963                                 'page_namespace' => $nt->getNamespace(),
1964                                 'page_title'     => $nt->getDBkey(),
1965                                 'page_latest'    => $nullRevId,
1966                         ),
1967                         /* WHERE */ array( 'page_id' => $oldid ),
1968                         $fname
1969                 );
1970
1971                 $linkCache->clearLink( $nt->getPrefixedDBkey() );
1972
1973                 # Insert redirect
1974                 $mwRedir = MagicWord::get( 'redirect' );
1975                 $redirectText = $mwRedir->getSynonym( 0 ) . ' [[' . $nt->getPrefixedText() . "]]\n";
1976                 $redirectArticle = new Article( $this );
1977                 $newid = $redirectArticle->insertOn( $dbw );
1978                 $redirectRevision = new Revision( array(
1979                         'page'    => $newid,
1980                         'comment' => $comment,
1981                         'text'    => $redirectText ) );
1982                 $revid = $redirectRevision->insertOn( $dbw );
1983                 $redirectArticle->updateRevisionOn( $dbw, $redirectRevision, 0 );
1984                 $linkCache->clearLink( $this->getPrefixedDBkey() );
1985
1986                 # Log the move
1987                 $log = new LogPage( 'move' );
1988                 $log->addEntry( 'move', $this, $reason, array( 1 => $nt->getPrefixedText()) );
1989
1990                 # Purge caches as per article creation
1991                 Article::onArticleCreate( $nt );
1992
1993                 # Record the just-created redirect's linking to the page
1994                 $dbw->insert( 'pagelinks',
1995                         array(
1996                                 'pl_from'      => $newid,
1997                                 'pl_namespace' => $nt->getNamespace(),
1998                                 'pl_title'     => $nt->getDBkey() ),
1999                         $fname );
2000
2001                 # Purge old title from squid
2002                 # The new title, and links to the new title, are purged in Article::onArticleCreate()
2003                 $this->purgeSquid();
2004         }
2005
2006         /**
2007          * Checks if $this can be moved to a given Title
2008          * - Selects for update, so don't call it unless you mean business
2009          *
2010          * @param Title &$nt the new title to check
2011          * @access public
2012          */
2013         function isValidMoveTarget( $nt ) {
2014
2015                 $fname = 'Title::isValidMoveTarget';
2016                 $dbw =& wfGetDB( DB_MASTER );
2017
2018                 # Is it a redirect?
2019                 $id  = $nt->getArticleID();
2020                 $obj = $dbw->selectRow( array( 'page', 'revision', 'text'),
2021                         array( 'page_is_redirect','old_text','old_flags' ),
2022                         array( 'page_id' => $id, 'page_latest=rev_id', 'rev_text_id=old_id' ),
2023                         $fname, 'FOR UPDATE' );
2024
2025                 if ( !$obj || 0 == $obj->page_is_redirect ) {
2026                         # Not a redirect
2027                         wfDebug( __METHOD__ . ": not a redirect\n" );
2028                         return false;
2029                 }
2030                 $text = Revision::getRevisionText( $obj );
2031
2032                 # Does the redirect point to the source?
2033                 # Or is it a broken self-redirect, usually caused by namespace collisions?
2034                 if ( preg_match( "/\\[\\[\\s*([^\\]\\|]*)]]/", $text, $m ) ) {
2035                         $redirTitle = Title::newFromText( $m[1] );
2036                         if( !is_object( $redirTitle ) ||
2037                                 ( $redirTitle->getPrefixedDBkey() != $this->getPrefixedDBkey() &&
2038                                 $redirTitle->getPrefixedDBkey() != $nt->getPrefixedDBkey() ) ) {
2039                                 wfDebug( __METHOD__ . ": redirect points to other page\n" );
2040                                 return false;
2041                         }
2042                 } else {
2043                         # Fail safe
2044                         wfDebug( __METHOD__ . ": failsafe\n" );
2045                         return false;
2046                 }
2047
2048                 # Does the article have a history?
2049                 $row = $dbw->selectRow( array( 'page', 'revision'),
2050                         array( 'rev_id' ),
2051                         array( 'page_namespace' => $nt->getNamespace(),
2052                                 'page_title' => $nt->getDBkey(),
2053                                 'page_id=rev_page AND page_latest != rev_id'
2054                         ), $fname, 'FOR UPDATE'
2055                 );
2056
2057                 # Return true if there was no history
2058                 return $row === false;
2059         }
2060
2061         /**
2062          * Create a redirect; fails if the title already exists; does
2063          * not notify RC
2064          *
2065          * @param Title $dest the destination of the redirect
2066          * @param string $comment the comment string describing the move
2067          * @return bool true on success
2068          * @access public
2069          */
2070         function createRedirect( $dest, $comment ) {
2071                 if ( $this->getArticleID() ) {
2072                         return false;
2073                 }
2074
2075                 $fname = 'Title::createRedirect';
2076                 $dbw =& wfGetDB( DB_MASTER );
2077
2078                 $article = new Article( $this );
2079                 $newid = $article->insertOn( $dbw );
2080                 $revision = new Revision( array(
2081                         'page'      => $newid,
2082                         'comment'   => $comment,
2083                         'text'      => "#REDIRECT [[" . $dest->getPrefixedText() . "]]\n",
2084                         ) );
2085                 $revisionId = $revision->insertOn( $dbw );
2086                 $article->updateRevisionOn( $dbw, $revision, 0 );
2087
2088                 # Link table
2089                 $dbw->insert( 'pagelinks',
2090                         array(
2091                                 'pl_from'      => $newid,
2092                                 'pl_namespace' => $dest->getNamespace(),
2093                                 'pl_title'     => $dest->getDbKey()
2094                         ), $fname
2095                 );
2096
2097                 Article::onArticleCreate( $this );
2098                 return true;
2099         }
2100
2101         /**
2102          * Get categories to which this Title belongs and return an array of
2103          * categories' names.
2104          *
2105          * @return array an array of parents in the form:
2106          *      $parent => $currentarticle
2107          * @access public
2108          */
2109         function getParentCategories() {
2110                 global $wgContLang;
2111
2112                 $titlekey = $this->getArticleId();
2113                 $dbr =& wfGetDB( DB_SLAVE );
2114                 $categorylinks = $dbr->tableName( 'categorylinks' );
2115
2116                 # NEW SQL
2117                 $sql = "SELECT * FROM $categorylinks"
2118                      ." WHERE cl_from='$titlekey'"
2119                          ." AND cl_from <> '0'"
2120                          ." ORDER BY cl_sortkey";
2121
2122                 $res = $dbr->query ( $sql ) ;
2123
2124                 if($dbr->numRows($res) > 0) {
2125                         while ( $x = $dbr->fetchObject ( $res ) )
2126                                 //$data[] = Title::newFromText($wgContLang->getNSText ( NS_CATEGORY ).':'.$x->cl_to);
2127                                 $data[$wgContLang->getNSText ( NS_CATEGORY ).':'.$x->cl_to] = $this->getFullText();
2128                         $dbr->freeResult ( $res ) ;
2129                 } else {
2130                         $data = '';
2131                 }
2132                 return $data;
2133         }
2134
2135         /**
2136          * Get a tree of parent categories
2137          * @param array $children an array with the children in the keys, to check for circular refs
2138          * @return array
2139          * @access public
2140          */
2141         function getParentCategoryTree( $children = array() ) {
2142                 $parents = $this->getParentCategories();
2143
2144                 if($parents != '') {
2145                         foreach($parents as $parent => $current) {
2146                                 if ( array_key_exists( $parent, $children ) ) {
2147                                         # Circular reference
2148                                         $stack[$parent] = array();
2149                                 } else {
2150                                         $nt = Title::newFromText($parent);
2151                                         if ( $nt ) {
2152                                                 $stack[$parent] = $nt->getParentCategoryTree( $children + array($parent => 1) );
2153                                         }
2154                                 }
2155                         }
2156                         return $stack;
2157                 } else {
2158                         return array();
2159                 }
2160         }
2161
2162
2163         /**
2164          * Get an associative array for selecting this title from
2165          * the "page" table
2166          *
2167          * @return array
2168          * @access public
2169          */
2170         function pageCond() {
2171                 return array( 'page_namespace' => $this->mNamespace, 'page_title' => $this->mDbkeyform );
2172         }
2173
2174         /**
2175          * Get the revision ID of the previous revision
2176          *
2177          * @param integer $revision  Revision ID. Get the revision that was before this one.
2178          * @return interger $oldrevision|false
2179          */
2180         function getPreviousRevisionID( $revision ) {
2181                 $dbr =& wfGetDB( DB_SLAVE );
2182                 return $dbr->selectField( 'revision', 'rev_id',
2183                         'rev_page=' . intval( $this->getArticleId() ) .
2184                         ' AND rev_id<' . intval( $revision ) . ' ORDER BY rev_id DESC' );
2185         }
2186
2187         /**
2188          * Get the revision ID of the next revision
2189          *
2190          * @param integer $revision  Revision ID. Get the revision that was after this one.
2191          * @return interger $oldrevision|false
2192          */
2193         function getNextRevisionID( $revision ) {
2194                 $dbr =& wfGetDB( DB_SLAVE );
2195                 return $dbr->selectField( 'revision', 'rev_id',
2196                         'rev_page=' . intval( $this->getArticleId() ) .
2197                         ' AND rev_id>' . intval( $revision ) . ' ORDER BY rev_id' );
2198         }
2199
2200         /**
2201          * Compare with another title.
2202          *
2203          * @param Title $title
2204          * @return bool
2205          */
2206         function equals( $title ) {
2207                 // Note: === is necessary for proper matching of number-like titles.
2208                 return $this->getInterwiki() === $title->getInterwiki()
2209                         && $this->getNamespace() == $title->getNamespace()
2210                         && $this->getDbkey() === $title->getDbkey();
2211         }
2212
2213         /**
2214          * Check if page exists
2215          * @return bool
2216          */
2217         function exists() {
2218                 return $this->getArticleId() != 0;
2219         }
2220
2221         /**
2222          * Should a link should be displayed as a known link, just based on its title?
2223          *
2224          * Currently, a self-link with a fragment and special pages are in
2225          * this category. Special pages never exist in the database.
2226          */
2227         function isAlwaysKnown() {
2228                 return  $this->isExternal() || ( 0 == $this->mNamespace && "" == $this->mDbkeyform )
2229                   || NS_SPECIAL == $this->mNamespace;
2230         }
2231
2232         /**
2233          * Update page_touched timestamps and send squid purge messages for
2234          * pages linking to this title. May be sent to the job queue depending
2235          * on the number of links. Typically called on create and delete.
2236          */
2237         function touchLinks() {
2238                 $u = new HTMLCacheUpdate( $this, 'pagelinks' );
2239                 $u->doUpdate();
2240
2241                 if ( $this->getNamespace() == NS_CATEGORY ) {
2242                         $u = new HTMLCacheUpdate( $this, 'categorylinks' );
2243                         $u->doUpdate();
2244                 }
2245         }
2246
2247         /**
2248          * Get the last touched timestamp
2249          */
2250         function getTouched() {
2251                 $dbr =& wfGetDB( DB_SLAVE );
2252                 $touched = $dbr->selectField( 'page', 'page_touched',
2253                         array(
2254                                 'page_namespace' => $this->getNamespace(),
2255                                 'page_title' => $this->getDBkey()
2256                         ), __METHOD__
2257                 );
2258                 return $touched;
2259         }
2260
2261         /**
2262          * Get a cached value from a global cache that is invalidated when this page changes
2263          * @param string $key the key
2264          * @param callback $callback A callback function which generates the value on cache miss
2265          */
2266         function getRelatedCache( $memc, $key, $expiry, $callback, $params = array() ) {
2267                 $touched = $this->getTouched();
2268                 $cacheEntry = $memc->get( $key );
2269                 if ( $cacheEntry ) {
2270                         if ( $cacheEntry['touched'] >= $touched ) {
2271                                 return $cacheEntry['value'];
2272                         } else {
2273                                 wfDebug( __METHOD__.": $key expired\n" );
2274                         }
2275                 } else {
2276                         wfDebug( __METHOD__.": $key not found\n" );
2277                 }
2278                 $value = call_user_func_array( $callback, $params );
2279                 $cacheEntry = array(
2280                         'value' => $value,
2281                         'touched' => $touched
2282                 );
2283                 $memc->set( $key, $cacheEntry, $expiry );
2284                 return $value;
2285         }
2286
2287         function trackbackURL() {
2288                 global $wgTitle, $wgScriptPath, $wgServer;
2289
2290                 return "$wgServer$wgScriptPath/trackback.php?article="
2291                         . htmlspecialchars(urlencode($wgTitle->getPrefixedDBkey()));
2292         }
2293
2294         function trackbackRDF() {
2295                 $url = htmlspecialchars($this->getFullURL());
2296                 $title = htmlspecialchars($this->getText());
2297                 $tburl = $this->trackbackURL();
2298
2299                 return "
2300 <rdf:RDF xmlns:rdf=\"http://www.w3.org/1999/02/22-rdf-syntax-ns#\"
2301          xmlns:dc=\"http://purl.org/dc/elements/1.1/\"
2302          xmlns:trackback=\"http://madskills.com/public/xml/rss/module/trackback/\">
2303 <rdf:Description
2304    rdf:about=\"$url\"
2305    dc:identifier=\"$url\"
2306    dc:title=\"$title\"
2307    trackback:ping=\"$tburl\" />
2308 </rdf:RDF>";
2309         }
2310
2311         /**
2312          * Generate strings used for xml 'id' names in monobook tabs
2313          * @return string
2314          */
2315         function getNamespaceKey() {
2316                 switch ($this->getNamespace()) {
2317                         case NS_MAIN:
2318                         case NS_TALK:
2319                                 return 'nstab-main';
2320                         case NS_USER:
2321                         case NS_USER_TALK:
2322                                 return 'nstab-user';
2323                         case NS_MEDIA:
2324                                 return 'nstab-media';
2325                         case NS_SPECIAL:
2326                                 return 'nstab-special';
2327                         case NS_PROJECT:
2328                         case NS_PROJECT_TALK:
2329                                 return 'nstab-project';
2330                         case NS_IMAGE:
2331                         case NS_IMAGE_TALK:
2332                                 return 'nstab-image';
2333                         case NS_MEDIAWIKI:
2334                         case NS_MEDIAWIKI_TALK:
2335                                 return 'nstab-mediawiki';
2336                         case NS_TEMPLATE:
2337                         case NS_TEMPLATE_TALK:
2338                                 return 'nstab-template';
2339                         case NS_HELP:
2340                         case NS_HELP_TALK:
2341                                 return 'nstab-help';
2342                         case NS_CATEGORY:
2343                         case NS_CATEGORY_TALK:
2344                                 return 'nstab-category';
2345                         default:
2346                                 return 'nstab-' . strtolower( $this->getSubjectNsText() );
2347                 }
2348         }
2349 }
2350 ?>