includes/Title.php

   1 <?php
   2 # See title.doc
   3
   4 /* private static */ $title_interwiki_cache = array();
   5
   6 # Title class
   7 #
   8 # * Represents a title, which may contain an interwiki designation or namespace
   9 # * Can fetch various kinds of data from the database, albeit inefficiently.
  10 #
  11 class Title {
  12         # All member variables should be considered private
  13         # Please use the accessor functions
  14
  15         var $mTextform;           # Text form (spaces not underscores) of the main part
  16         var $mUrlform;            # URL-encoded form of the main part
  17         var $mDbkeyform;          # Main part with underscores
  18         var $mNamespace;          # Namespace index, i.e. one of the NS_xxxx constants
  19         var $mInterwiki;          # Interwiki prefix (or null string)
  20         var $mFragment;           # Title fragment (i.e. the bit after the #)
  21         var $mArticleID;          # Article ID, fetched from the link cache on demand
  22         var $mRestrictions;       # Array of groups allowed to edit this article
  23                               # Only null or "sysop" are supported
  24         var $mRestrictionsLoaded; # Boolean for initialisation on demand
  25         var $mPrefixedText;       # Text form including namespace/interwiki, initialised on demand
  26         var $mDefaultNamespace;   # Namespace index when there is no namespace
  27                               # Zero except in {{transclusion}} tags
  28
  29 #----------------------------------------------------------------------------
  30 #   Construction
  31 #----------------------------------------------------------------------------
  32
  33         /* private */ function Title()
  34         {
  35                 $this->mInterwiki = $this->mUrlform =
  36                 $this->mTextform = $this->mDbkeyform = "";
  37                 $this->mArticleID = -1;
  38                 $this->mNamespace = 0;
  39                 $this->mRestrictionsLoaded = false;
  40                 $this->mRestrictions = array();
  41         $this->mDefaultNamespace = 0;
  42         }
  43
  44         # From a prefixed DB key
  45         /* static */ function newFromDBkey( $key )
  46         {
  47                 $t = new Title();
  48                 $t->mDbkeyform = $key;
  49                 if( $t->secureAndSplit() )
  50                         return $t;
  51                 else
  52                         return NULL;
  53         }
  54
  55         # From text, such as what you would find in a link
  56         /* static */ function newFromText( $text, $defaultNamespace = 0 )
  57         {
  58                 static $trans;
  59                 $fname = "Title::newFromText";
  60                 wfProfileIn( $fname );
  61
  62                 # Note - mixing latin1 named entities and unicode numbered
  63                 # ones will result in a bad link.
  64                 if( !isset( $trans ) ) {
  65                         global $wgInputEncoding;
  66                         $trans = array_flip( get_html_translation_table( HTML_ENTITIES ) );
  67                         if( strcasecmp( "utf-8", $wgInputEncoding ) == 0 ) {
  68                                 $trans = array_map( "utf8_encode", $trans );
  69                         }
  70                 }
  71
  72                 if( is_object( $text ) ) {
  73                         wfDebugDieBacktrace( "Called with object instead of string." );
  74                 }
  75                 $text = strtr( $text, $trans );
  76
  77                 $text = wfMungeToUtf8( $text );
  78
  79
  80                 # What was this for? TS 2004-03-03
  81                 # $text = urldecode( $text );
  82
  83                 $t = new Title();
  84                 $t->mDbkeyform = str_replace( " ", "_", $text );
  85                 $t->mDefaultNamespace = $defaultNamespace;
  86
  87                 wfProfileOut( $fname );
  88                 if ( !is_object( $t ) ) {
  89                         var_dump( debug_backtrace() );
  90                 }
  91                 if( $t->secureAndSplit() ) {
  92                         return $t;
  93                 } else {
  94                         return NULL;
  95                 }
  96         }
  97
  98         # From a URL-encoded title
  99         /* static */ function newFromURL( $url )
 100         {
 101                 global $wgLang, $wgServer;
 102                 $t = new Title();
 103                 $s = urldecode( $url ); # This is technically wrong, as anything
 104                                                                 # we've gotten is already decoded by PHP.
 105                                                                 # Kept for backwards compatibility with
 106                                                                 # buggy URLs we had for a while...
 107                 $s = $url;
 108
 109                 # For links that came from outside, check for alternate/legacy
 110                 # character encoding.
 111                 wfDebug( "Servr: $wgServer\n" );
 112                 if( empty( $_SERVER["HTTP_REFERER"] ) ||
 113                         strncmp($wgServer, $_SERVER["HTTP_REFERER"], strlen( $wgServer ) ) )
 114                 {
 115                         $s = $wgLang->checkTitleEncoding( $s );
 116                 } else {
 117                         wfDebug( "Refer: {$_SERVER['HTTP_REFERER']}\n" );
 118                 }
 119
 120                 $t->mDbkeyform = str_replace( " ", "_", $s );
 121                 if( $t->secureAndSplit() ) {
 122
 123                         # check that lenght of title is < cur_title size
 124                         $sql = "SHOW COLUMNS FROM cur LIKE \"cur_title\";";
 125                         $cur_title_object = wfFetchObject(wfQuery( $sql, DB_READ ));
 126
 127                         preg_match( "/\((.*)\)/", $cur_title_object->Type, $cur_title_size);
 128
 129                         if (strlen($t->mDbkeyform) > $cur_title_size[1] ) {
 130                                 return NULL;
 131                         }
 132
 133                         return $t;
 134                 } else {
 135                         return NULL;
 136                 }
 137         }
 138
 139         # From a cur_id
 140         # This is inefficiently implemented, the cur row is requested but not
 141         # used for anything else
 142         /* static */ function newFromID( $id )
 143         {
 144                 $fname = "Title::newFromID";
 145                 $row = wfGetArray( "cur", array( "cur_namespace", "cur_title" ),
 146                         array( "cur_id" => $id ), $fname );
 147                 if ( $row !== false ) {
 148                         $title = Title::makeTitle( $row->cur_namespace, $row->cur_title );
 149                 } else {
 150                         $title = NULL;
 151                 }
 152                 return $title;
 153         }
 154
 155         # From a namespace index and a DB key
 156         /* static */ function makeTitle( $ns, $title )
 157         {
 158                 $t = new Title();
 159                 $t->mDbkeyform = Title::makeName( $ns, $title );
 160                 if( $t->secureAndSplit() ) {
 161                         return $t;
 162                 } else {
 163                         return NULL;
 164                 }
 165         }
 166
 167         function newMainPage()
 168         {
 169                 return Title::newFromText( wfMsg( "mainpage" ) );
 170         }
 171
 172 #----------------------------------------------------------------------------
 173 #       Static functions
 174 #----------------------------------------------------------------------------
 175
 176         # Get the prefixed DB key associated with an ID
 177         /* static */ function nameOf( $id )
 178         {
 179                 $sql = "SELECT cur_namespace,cur_title FROM cur WHERE " .
 180                   "cur_id={$id}";
 181                 $res = wfQuery( $sql, DB_READ, "Article::nameOf" );
 182                 if ( 0 == wfNumRows( $res ) ) { return NULL; }
 183
 184                 $s = wfFetchObject( $res );
 185                 $n = Title::makeName( $s->cur_namespace, $s->cur_title );
 186                 return $n;
 187         }
 188
 189         # Get a regex character class describing the legal characters in a link
 190         /* static */ function legalChars()
 191         {
 192                 # Missing characters:
 193                 #  * []|# Needed for link syntax
 194                 #  * % and + are corrupted by Apache when they appear in the path
 195                 #
 196                 # Theoretically 0x80-0x9F of ISO 8859-1 should be disallowed, but
 197                 # this breaks interlanguage links
 198
 199                 $set = " !\"$&'()*,\\-.\\/0-9:;<=>?@A-Z\\\\^_`a-z{}~\\x80-\\xFF";
 200                 return $set;
 201         }
 202
 203         # Returns a stripped-down a title string ready for the search index
 204         # Takes a namespace index and a text-form main part
 205         /* static */ function indexTitle( $ns, $title )
 206         {
 207                 global $wgDBminWordLen, $wgLang;
 208
 209                 $lc = SearchEngine::legalSearchChars() . "&#;";
 210                 $t = $wgLang->stripForSearch( $title );
 211                 $t = preg_replace( "/[^{$lc}]+/", " ", $t );
 212                 $t = strtolower( $t );
 213
 214                 # Handle 's, s'
 215                 $t = preg_replace( "/([{$lc}]+)'s( |$)/", "\\1 \\1's ", $t );
 216                 $t = preg_replace( "/([{$lc}]+)s'( |$)/", "\\1s ", $t );
 217
 218                 $t = preg_replace( "/\\s+/", " ", $t );
 219
 220                 if ( $ns == Namespace::getImage() ) {
 221                         $t = preg_replace( "/ (png|gif|jpg|jpeg|ogg)$/", "", $t );
 222                 }
 223                 return trim( $t );
 224         }
 225
 226         # Make a prefixed DB key from a DB key and a namespace index
 227         /* static */ function makeName( $ns, $title )
 228         {
 229                 global $wgLang;
 230
 231                 $n = $wgLang->getNsText( $ns );
 232                 if ( "" == $n ) { return $title; }
 233                 else { return "{$n}:{$title}"; }
 234         }
 235
 236         # Arguably static
 237         # Returns the URL associated with an interwiki prefix
 238         # The URL contains $1, which is replaced by the title
 239         function getInterwikiLink( $key )
 240         {
 241                 global $wgMemc, $wgDBname;
 242                 static $title_interwiki_cache = array();
 243
 244                 $k = "$wgDBname:interwiki:$key";
 245
 246                 if( array_key_exists( $k, $title_interwiki_cache ) )
 247                         return $title_interwiki_cache[$k]->iw_url;
 248
 249                 $s = $wgMemc->get( $k );
 250                 if( $s ) {
 251                         $title_interwiki_cache[$k] = $s;
 252                         return $s->iw_url;
 253                 }
 254                 $dkey = wfStrencode( $key );
 255                 $query = "SELECT iw_url FROM interwiki WHERE iw_prefix='$dkey'";
 256                 $res = wfQuery( $query, DB_READ, "Title::getInterwikiLink" );
 257                 if(!$res) return "";
 258
 259                 $s = wfFetchObject( $res );
 260                 if(!$s) {
 261                         $s = (object)false;
 262                         $s->iw_url = "";
 263                 }
 264                 $wgMemc->set( $k, $s );
 265                 $title_interwiki_cache[$k] = $s;
 266                 return $s->iw_url;
 267         }
 268
 269         # Update the cur_touched field for an array of title objects
 270         # Inefficient unless the IDs are already loaded into the link cache
 271         /* static */ function touchArray( $titles, $timestamp = "" ) {
 272                 if ( count( $titles ) == 0 ) {
 273                         return;
 274                 }
 275                 if ( $timestamp == "" ) {
 276                         $timestamp = wfTimestampNow();
 277                 }
 278                 $sql = "UPDATE cur SET cur_touched='{$timestamp}' WHERE cur_id IN (";
 279                 $first = true;
 280
 281                 foreach ( $titles as $title ) {
 282                         if ( ! $first ) {
 283                                 $sql .= ",";
 284                         }
 285
 286                         $first = false;
 287                         $sql .= $title->getArticleID();
 288                 }
 289                 $sql .= ")";
 290                 if ( ! $first ) {
 291                         wfQuery( $sql, DB_WRITE, "Title::touchArray" );
 292                 }
 293         }
 294
 295 #----------------------------------------------------------------------------
 296 #       Other stuff
 297 #----------------------------------------------------------------------------
 298
 299         # Simple accessors
 300         # See the definitions at the top of this file
 301
 302         function getText() { return $this->mTextform; }
 303         function getPartialURL() { return $this->mUrlform; }
 304         function getDBkey() { return $this->mDbkeyform; }
 305         function getNamespace() { return $this->mNamespace; }
 306         function setNamespace( $n ) { $this->mNamespace = $n; }
 307         function getInterwiki() { return $this->mInterwiki; }
 308         function getFragment() { return $this->mFragment; }
 309         function getDefaultNamespace() { return $this->mDefaultNamespace; }
 310
 311         # Get title for search index
 312         function getIndexTitle()
 313         {
 314                 return Title::indexTitle( $this->mNamespace, $this->mTextform );
 315         }
 316
 317         # Get prefixed title with underscores
 318         function getPrefixedDBkey()
 319         {
 320                 $s = $this->prefix( $this->mDbkeyform );
 321                 $s = str_replace( " ", "_", $s );
 322                 return $s;
 323         }
 324
 325         # Get prefixed title with spaces
 326         # This is the form usually used for display
 327         function getPrefixedText()
 328         {
 329                 if ( empty( $this->mPrefixedText ) ) {
 330                         $s = $this->prefix( $this->mTextform );
 331                         $s = str_replace( "_", " ", $s );
 332                         $this->mPrefixedText = $s;
 333                 }
 334                 return $this->mPrefixedText;
 335         }
 336
 337         # Get a URL-encoded title (not an actual URL) including interwiki
 338         function getPrefixedURL()
 339         {
 340                 $s = $this->prefix( $this->mDbkeyform );
 341                 $s = str_replace( " ", "_", $s );
 342
 343                 $s = wfUrlencode ( $s ) ;
 344
 345                 # Cleaning up URL to make it look nice -- is this safe?
 346                 $s = preg_replace( "/%3[Aa]/", ":", $s );
 347                 $s = preg_replace( "/%2[Ff]/", "/", $s );
 348                 $s = str_replace( "%28", "(", $s );
 349                 $s = str_replace( "%29", ")", $s );
 350
 351                 return $s;
 352         }
 353
 354         # Get a real URL referring to this title, with interwiki link and fragment
 355         function getFullURL( $query = "" )
 356         {
 357                 global $wgLang, $wgArticlePath, $wgServer, $wgScript;
 358
 359                 if ( "" == $this->mInterwiki ) {
 360                         $p = $wgArticlePath;
 361                         return $wgServer . $this->getLocalUrl( $query );
 362                 }
 363
 364                 $p = $this->getInterwikiLink( $this->mInterwiki );
 365                 $n = $wgLang->getNsText( $this->mNamespace );
 366                 if ( "" != $n ) { $n .= ":"; }
 367                 $u = str_replace( "$1", $n . $this->mUrlform, $p );
 368                 if ( "" != $this->mFragment ) {
 369                         $u .= "#" . wfUrlencode( $this->mFragment );
 370                 }
 371                 return $u;
 372         }
 373
 374         # Get a URL with an optional query string, no fragment
 375         # * If $query=="", it will use $wgArticlePath
 376         # * Returns a full for an interwiki link, loses any query string
 377         # * Optionally adds the server and escapes for HTML
 378         # * Setting $query to "-" makes an old-style URL with nothing in the
 379         #   query except a title
 380
 381         function getURL() {
 382                 die( "Call to obsolete obsolete function Title::getURL()" );
 383         }
 384
 385         function getLocalURL( $query = "" )
 386         {
 387                 global $wgLang, $wgArticlePath, $wgScript;
 388
 389                 if ( $this->isExternal() ) {
 390                         return $this->getFullURL();
 391                 }
 392
 393                 $dbkey = wfUrlencode( $this->getPrefixedDBkey() );
 394                 if ( $query == "" ) {
 395                         $url = str_replace( "$1", $dbkey, $wgArticlePath );
 396                 } else {
 397                         if ( $query == "-" ) {
 398                                 $query = "";
 399                         }
 400                         if ( $wgScript != "" ) {
 401                                 $url = "{$wgScript}?title={$dbkey}&{$query}";
 402                         } else {
 403                                 # Top level wiki
 404                                 $url = "/{$dbkey}?{$query}";
 405                         }
 406                 }
 407                 return $url;
 408         }
 409
 410         function escapeLocalURL( $query = "" ) {
 411                 return wfEscapeHTML( $this->getLocalURL( $query ) );
 412         }
 413
 414         function escapeFullURL( $query = "" ) {
 415                 return wfEscapeHTML( $this->getFullURL( $query ) );
 416         }
 417
 418         function getInternalURL( $query = "" ) {
 419                 # Used in various Squid-related code, in case we have a different
 420                 # internal hostname for the server than the exposed one.
 421                 global $wgInternalServer;
 422                 return $wgInternalServer . $this->getLocalURL( $query );
 423         }
 424
 425         # Get the edit URL, or a null string if it is an interwiki link
 426         function getEditURL()
 427         {
 428                 global $wgServer, $wgScript;
 429
 430                 if ( "" != $this->mInterwiki ) { return ""; }
 431                 $s = $this->getLocalURL( "action=edit" );
 432
 433                 return $s;
 434         }
 435
 436         # Get HTML-escaped displayable text
 437         # For the title field in <a> tags
 438         function getEscapedText()
 439         {
 440                 return wfEscapeHTML( $this->getPrefixedText() );
 441         }
 442
 443         # Is the title interwiki?
 444         function isExternal() { return ( "" != $this->mInterwiki ); }
 445
 446         # Does the title correspond to a protected article?
 447         function isProtected()
 448         {
 449                 if ( -1 == $this->mNamespace ) { return true; }
 450                 $a = $this->getRestrictions();
 451                 if ( in_array( "sysop", $a ) ) { return true; }
 452                 return false;
 453         }
 454
 455         # Is the page a log page, i.e. one where the history is messed up by
 456         # LogPage.php? This used to be used for suppressing diff links in recent
 457         # changes, but now that's done by setting a flag in the recentchanges
 458         # table. Hence, this probably is no longer used.
 459         function isLog()
 460         {
 461                 if ( $this->mNamespace != Namespace::getWikipedia() ) {
 462                         return false;
 463                 }
 464                 if ( ( 0 == strcmp( wfMsg( "uploadlogpage" ), $this->mDbkeyform ) ) ||
 465                   ( 0 == strcmp( wfMsg( "dellogpage" ), $this->mDbkeyform ) ) ) {
 466                         return true;
 467                 }
 468                 return false;
 469         }
 470
 471         # Is $wgUser is watching this page?
 472         function userIsWatching()
 473         {
 474                 global $wgUser;
 475
 476                 if ( -1 == $this->mNamespace ) { return false; }
 477                 if ( 0 == $wgUser->getID() ) { return false; }
 478
 479                 return $wgUser->isWatched( $this );
 480         }
 481
 482         # Can $wgUser edit this page?
 483         function userCanEdit()
 484         {
 485                 global $wgUser;
 486
 487                 if ( -1 == $this->mNamespace ) { return false; }
 488                 # if ( 0 == $this->getArticleID() ) { return false; }
 489                 if ( $this->mDbkeyform == "_" ) { return false; }
 490                 # protect css/js subpages of user pages
 491                 # XXX: this might be better using restrictions
 492                 if( Namespace::getUser() == $this->mNamespace
 493                         and preg_match("/\\.(css|js)$/", $this->mTextform )
 494                         and !$wgUser->isDeveloper()
 495                         and !preg_match("/^".$wgUser->getName()."/", $this->mTextform) )
 496                 { return false; }
 497
 498                 $ur = $wgUser->getRights();
 499                 foreach ( $this->getRestrictions() as $r ) {
 500                         if ( "" != $r && ( ! in_array( $r, $ur ) ) ) {
 501                                 return false;
 502                         }
 503                 }
 504                 return true;
 505         }
 506
 507         # Accessor/initialisation for mRestrictions
 508         function getRestrictions()
 509         {
 510                 $id = $this->getArticleID();
 511                 if ( 0 == $id ) { return array(); }
 512
 513                 if ( ! $this->mRestrictionsLoaded ) {
 514                         $res = wfGetSQL( "cur", "cur_restrictions", "cur_id=$id" );
 515                         $this->mRestrictions = explode( ",", trim( $res ) );
 516                         $this->mRestrictionsLoaded = true;
 517                 }
 518                 return $this->mRestrictions;
 519         }
 520
 521         # Is there a version of this page in the deletion archive?
 522         function isDeleted() {
 523                 $ns = $this->getNamespace();
 524                 $t = wfStrencode( $this->getDBkey() );
 525                 $sql = "SELECT COUNT(*) AS n FROM archive WHERE ar_namespace=$ns AND ar_title='$t'";
 526                 if( $res = wfQuery( $sql, DB_READ ) ) {
 527                         $s = wfFetchObject( $res );
 528                         return $s->n;
 529                 }
 530                 return 0;
 531         }
 532
 533         # Get the article ID from the link cache
 534         # Used very heavily, e.g. in Parser::replaceInternalLinks()
 535         function getArticleID()
 536         {
 537                 global $wgLinkCache;
 538
 539                 if ( -1 != $this->mArticleID ) { return $this->mArticleID; }
 540                 $this->mArticleID = $wgLinkCache->addLinkObj( $this );
 541                 return $this->mArticleID;
 542         }
 543
 544         # This clears some fields in this object, and clears any associated keys in the
 545         # "bad links" section of $wgLinkCache. This is called from Article::insertNewArticle()
 546         # to allow loading of the new cur_id. It's also called from Article::doDeleteArticle()
 547         function resetArticleID( $newid )
 548         {
 549                 global $wgLinkCache;
 550                 $wgLinkCache->clearBadLink( $this->getPrefixedDBkey() );
 551
 552                 if ( 0 == $newid ) { $this->mArticleID = -1; }
 553                 else { $this->mArticleID = $newid; }
 554                 $this->mRestrictionsLoaded = false;
 555                 $this->mRestrictions = array();
 556         }
 557
 558         # Updates cur_touched
 559         # Called from LinksUpdate.php
 560         function invalidateCache() {
 561                 $now = wfTimestampNow();
 562                 $ns = $this->getNamespace();
 563                 $ti = wfStrencode( $this->getDBkey() );
 564                 $sql = "UPDATE cur SET cur_touched='$now' WHERE cur_namespace=$ns AND cur_title='$ti'";
 565                 return wfQuery( $sql, DB_WRITE, "Title::invalidateCache" );
 566         }
 567
 568         # Prefixes some arbitrary text with the namespace or interwiki prefix of this object
 569         /* private */ function prefix( $name )
 570         {
 571                 global $wgLang;
 572
 573                 $p = "";
 574                 if ( "" != $this->mInterwiki ) {
 575                         $p = $this->mInterwiki . ":";
 576                 }
 577                 if ( 0 != $this->mNamespace ) {
 578                         $p .= $wgLang->getNsText( $this->mNamespace ) . ":";
 579                 }
 580                 return $p . $name;
 581         }
 582
 583         # Secure and split - main initialisation function for this object
 584         #
 585         # Assumes that mDbkeyform has been set, and is urldecoded
 586     # and uses undersocres, but not otherwise munged.  This function
 587     # removes illegal characters, splits off the winterwiki and
 588     # namespace prefixes, sets the other forms, and canonicalizes
 589     # everything.
 590         #
 591         /* private */ function secureAndSplit()
 592         {
 593                 global $wgLang, $wgLocalInterwiki, $wgCapitalLinks;
 594                 $fname = "Title::secureAndSplit";
 595                 wfProfileIn( $fname );
 596
 597                 static $imgpre = false;
 598                 static $rxTc = false;
 599
 600                 # Initialisation
 601                 if ( $imgpre === false ) {
 602                         $imgpre = ":" . $wgLang->getNsText( Namespace::getImage() ) . ":";
 603                         $rxTc = "/[^" . Title::legalChars() . "]/";
 604                 }
 605
 606                 $this->mInterwiki = $this->mFragment = "";
 607                 $this->mNamespace = $this->mDefaultNamespace; # Usually NS_MAIN
 608
 609                 # Clean up whitespace
 610                 #
 611                 $t = preg_replace( "/[\\s_]+/", "_", $this->mDbkeyform );
 612                 $t = preg_replace( '/^_*(.*?)_*$/', '$1', $t );
 613
 614                 if ( "" == $t ) {
 615                         wfProfileOut( $fname );
 616                         return false;
 617                 }
 618
 619                 $this->mDbkeyform = $t;
 620                 $done = false;
 621
 622                 # :Image: namespace
 623                 if ( 0 == strncasecmp( $imgpre, $t, strlen( $imgpre ) ) ) {
 624                         $t = substr( $t, 1 );
 625                 }
 626
 627                 # Initial colon indicating main namespace
 628                 if ( ":" == $t{0} ) {
 629                         $r = substr( $t, 1 );
 630                         $this->mNamespace = NS_MAIN;
 631                 } else {
 632                         # Namespace or interwiki prefix
 633                         if ( preg_match( "/^((?:i|x|[a-z]{2,3})(?:-[a-z0-9]+)?|[A-Za-z0-9_\\x80-\\xff]+?)_*:_*(.*)$/", $t, $m ) ) {
 634                                 #$p = strtolower( $m[1] );
 635                                 $p = $m[1];
 636                                 $lowerNs = strtolower( $p );
 637                                 if ( $ns = Namespace::getCanonicalIndex( $lowerNs ) ) {
 638                                         # Canonical namespace
 639                                         $t = $m[2];
 640                                         $this->mNamespace = $ns;
 641                                 } elseif ( $ns = $wgLang->getNsIndex( $lowerNs )) {
 642                                         # Ordinary namespace
 643                                         $t = $m[2];
 644                                         $this->mNamespace = $ns;
 645                                 } elseif ( $this->getInterwikiLink( $p ) ) {
 646                                         # Interwiki link
 647                                         $t = $m[2];
 648                                         $this->mInterwiki = $p;
 649
 650                                         if ( !preg_match( "/^([A-Za-z0-9_\\x80-\\xff]+):(.*)$/", $t, $m ) ) {
 651                                                 $done = true;
 652                                         } elseif($this->mInterwiki != $wgLocalInterwiki) {
 653                                                 $done = true;
 654                                         }
 655                                 }
 656                         }
 657                         $r = $t;
 658                 }
 659
 660                 # Redundant interwiki prefix to the local wiki
 661                 if ( 0 == strcmp( $this->mInterwiki, $wgLocalInterwiki ) ) {
 662                         $this->mInterwiki = "";
 663                 }
 664                 # We already know that some pages won't be in the database!
 665                 #
 666                 if ( "" != $this->mInterwiki || -1 == $this->mNamespace ) {
 667                         $this->mArticleID = 0;
 668                 }
 669                 $f = strstr( $r, "#" );
 670                 if ( false !== $f ) {
 671                         $this->mFragment = substr( $f, 1 );
 672                         $r = substr( $r, 0, strlen( $r ) - strlen( $f ) );
 673                 }
 674
 675                 # Reject illegal characters.
 676                 #
 677                 if( preg_match( $rxTc, $r ) ) {
 678                         return false;
 679                 }
 680
 681                 # "." and ".." conflict with the directories of those names
 682                 if ( $r === "." || $r === ".." ) {
 683                         return false;
 684                 }
 685
 686                 # Initial capital letter
 687                 if( $wgCapitalLinks && $this->mInterwiki == "") {
 688                         $t = $wgLang->ucfirst( $r );
 689                 }
 690
 691                 # Fill fields
 692                 $this->mDbkeyform = $t;
 693                 $this->mUrlform = wfUrlencode( $t );
 694
 695                 $this->mTextform = str_replace( "_", " ", $t );
 696
 697                 wfProfileOut( $fname );
 698                 return true;
 699         }
 700
 701         # Get a title object associated with the talk page of this article
 702         function getTalkPage() {
 703                 return Title::makeTitle( Namespace::getTalk( $this->getNamespace() ), $this->getDBkey() );
 704         }
 705
 706         # Get a title object associated with the subject page of this talk page
 707         function getSubjectPage() {
 708                 return Title::makeTitle( Namespace::getSubject( $this->getNamespace() ), $this->getDBkey() );
 709         }
 710
 711         # Get an array of Title objects linking to this title
 712         # Also stores the IDs in the link cache
 713         function getLinksTo() {
 714                 global $wgLinkCache;
 715                 $id = $this->getArticleID();
 716                 $sql = "SELECT cur_namespace,cur_title,cur_id FROM cur,links WHERE l_from=cur_id AND l_to={$id}";
 717                 $res = wfQuery( $sql, DB_READ, "Title::getLinksTo" );
 718                 $retVal = array();
 719                 if ( wfNumRows( $res ) ) {
 720                         while ( $row = wfFetchObject( $res ) ) {
 721                                 $titleObj = Title::makeTitle( $row->cur_namespace, $row->cur_title );
 722                                 $wgLinkCache->addGoodLink( $row->cur_id, $titleObj->getPrefixedDBkey() );
 723                                 $retVal[] = $titleObj;
 724                         }
 725                 }
 726                 wfFreeResult( $res );
 727                 return $retVal;
 728         }
 729
 730         # Get an array of Title objects linking to this non-existent title
 731         # Also stores the IDs in the link cache
 732         function getBrokenLinksTo() {
 733                 global $wgLinkCache;
 734                 $encTitle = wfStrencode( $this->getPrefixedDBkey() );
 735                 $sql = "SELECT cur_namespace,cur_title,cur_id FROM brokenlinks,cur " .
 736                   "WHERE bl_from=cur_id AND bl_to='$encTitle'";
 737                 $res = wfQuery( $sql, DB_READ, "Title::getBrokenLinksTo" );
 738                 $retVal = array();
 739                 if ( wfNumRows( $res ) ) {
 740                         while ( $row = wfFetchObject( $res ) ) {
 741                                 $titleObj = Title::makeTitle( $row->cur_namespace, $row->cur_title );
 742                                 $wgLinkCache->addGoodLink( $titleObj->getPrefixedDBkey(), $row->cur_id );
 743                                 $retVal[] = $titleObj;
 744                         }
 745                 }
 746                 wfFreeResult( $res );
 747                 return $retVal;
 748         }
 749
 750         function getSquidURLs() {
 751                 return array(
 752                         $this->getInternalURL(),
 753                         $this->getInternalURL( "action=history" )
 754                 );
 755         }
 756
 757         function moveNoAuth( &$nt ) {
 758                 return $this->moveTo( $nt, false );
 759         }
 760
 761         # Move a title to a new location
 762         # Returns true on success, message name on failure
 763         # auth indicates whether wgUser's permissions should be checked
 764         function moveTo( &$nt, $auth = true ) {
 765                 if( !$this or !$nt ) {
 766                         return "badtitletext";
 767                 }
 768
 769                 $fname = "Title::move";
 770                 $oldid = $this->getArticleID();
 771                 $newid = $nt->getArticleID();
 772
 773                 if ( strlen( $nt->getDBkey() ) < 1 ) {
 774                         return "articleexists";
 775                 }
 776                 if ( ( ! Namespace::isMovable( $this->getNamespace() ) ) ||
 777                          ( "" == $this->getDBkey() ) ||
 778                          ( "" != $this->getInterwiki() ) ||
 779                          ( !$oldid ) ||
 780                      ( ! Namespace::isMovable( $nt->getNamespace() ) ) ||
 781                          ( "" == $nt->getDBkey() ) ||
 782                          ( "" != $nt->getInterwiki() ) ) {
 783                         return "badarticleerror";
 784                 }
 785
 786                 if ( $auth && ( !$this->userCanEdit() || !$nt->userCanEdit() ) ) {
 787                         return "protectedpage";
 788                 }
 789
 790                 # The move is allowed only if (1) the target doesn't exist, or
 791                 # (2) the target is a redirect to the source, and has no history
 792                 # (so we can undo bad moves right after they're done).
 793
 794                 if ( 0 != $newid ) { # Target exists; check for validity
 795                         if ( ! $this->isValidMoveTarget( $nt ) ) {
 796                                 return "articleexists";
 797                         }
 798                         $this->moveOverExistingRedirect( $nt );
 799                 } else { # Target didn't exist, do normal move.
 800                         $this->moveToNewTitle( $nt, $newid );
 801                 }
 802
 803                 # Update watchlists
 804
 805                 $oldnamespace = $this->getNamespace() & ~1;
 806                 $newnamespace = $nt->getNamespace() & ~1;
 807                 $oldtitle = $this->getDBkey();
 808                 $newtitle = $nt->getDBkey();
 809
 810                 if( $oldnamespace != $newnamespace && $oldtitle != $newtitle ) {
 811                         WatchedItem::duplicateEntries( $this, $nt );
 812                 }
 813
 814                 # Update search engine
 815                 $u = new SearchUpdate( $oldid, $nt->getPrefixedDBkey() );
 816                 $u->doUpdate();
 817                 $u = new SearchUpdate( $newid, $this->getPrefixedDBkey(), "" );
 818                 $u->doUpdate();
 819
 820                 return true;
 821         }
 822
 823         # Move page to title which is presently a redirect to the source page
 824
 825         /* private */ function moveOverExistingRedirect( &$nt )
 826         {
 827                 global $wgUser, $wgLinkCache, $wgUseSquid, $wgMwRedir;
 828                 $fname = "Title::moveOverExistingRedirect";
 829                 $comment = wfMsg( "1movedto2", $this->getPrefixedText(), $nt->getPrefixedText() );
 830
 831         $now = wfTimestampNow();
 832         $won = wfInvertTimestamp( $now );
 833                 $newid = $nt->getArticleID();
 834                 $oldid = $this->getArticleID();
 835
 836                 # Change the name of the target page:
 837                 wfUpdateArray(
 838                         /* table */ 'cur',
 839                         /* SET */ array(
 840                                 'cur_touched' => $now,
 841                                 'cur_namespace' => $nt->getNamespace(),
 842                                 'cur_title' => $nt->getDBkey()
 843                         ),
 844                         /* WHERE */ array( 'cur_id' => $oldid ),
 845                         $fname
 846                 );
 847                 $wgLinkCache->clearLink( $nt->getPrefixedDBkey() );
 848
 849                 # Repurpose the old redirect. We don't save it to history since
 850                 # by definition if we've got here it's rather uninteresting.
 851
 852                 $redirectText = $wgMwRedir->getSynonym( 0 ) . " [[" . $nt->getPrefixedText() . "]]\n";
 853                 wfUpdateArray(
 854                         /* table */ 'cur',
 855                         /* SET */ array(
 856                                 'cur_touched' => $now,
 857                                 'cur_timestamp' => $now,
 858                                 'inverse_timestamp' => $won,
 859                                 'cur_namespace' => $this->getNamespace(),
 860                                 'cur_title' => $this->getDBkey(),
 861                                 'cur_text' => $wgMwRedir->getSynonym( 0 ) . " [[" . $nt->getPrefixedText() . "]]\n",
 862                                 'cur_comment' => $comment,
 863                                 'cur_user' => $wgUser->getID(),
 864                                 'cur_minor_edit' => 0,
 865                                 'cur_counter' => 0,
 866                                 'cur_restrictions' => '',
 867                                 'cur_user_text' => $wgUser->getName(),
 868                                 'cur_is_redirect' => 1,
 869                                 'cur_is_new' => 1
 870                         ),
 871                         /* WHERE */ array( 'cur_id' => $newid ),
 872                         $fname
 873                 );
 874
 875                 $wgLinkCache->clearLink( $this->getPrefixedDBkey() );
 876
 877                 # Fix the redundant names for the past revisions of the target page.
 878                 # The redirect should have no old revisions.
 879                 wfUpdateArray(
 880                         /* table */ 'old',
 881                         /* SET */ array(
 882                                 'old_namespace' => $nt->getNamespace(),
 883                                 'old_title' => $nt->getDBkey(),
 884                         ),
 885                         /* WHERE */ array(
 886                                 'old_namespace' => $this->getNamespace(),
 887                                 'old_title' => $this->getDBkey(),
 888                         ),
 889                         $fname
 890                 );
 891
 892                 RecentChange::notifyMove( $now, $this, $nt, $wgUser, $comment );
 893
 894                 # Swap links
 895
 896                 # Load titles and IDs
 897                 $linksToOld = $this->getLinksTo();
 898                 $linksToNew = $nt->getLinksTo();
 899
 900                 # Make function to convert Titles to IDs
 901                 $titleToID = create_function('$t', 'return $t->getArticleID();');
 902
 903                 # Reassign links to old title
 904                 if ( count( $linksToOld ) ) {
 905                         $sql = "UPDATE links SET l_to=$newid WHERE l_from IN (";
 906                         $sql .= implode( ",", array_map( $titleToID, $linksToOld ) );
 907                         $sql .= ")";
 908                         wfQuery( $sql, DB_WRITE, $fname );
 909                 }
 910
 911                 # Reassign links to new title
 912                 if ( count( $linksToNew ) ) {
 913                         $sql = "UPDATE links SET l_to=$oldid WHERE l_from IN (";
 914                         $sql .= implode( ",", array_map( $titleToID, $linksToNew ) );
 915                         $sql .= ")";
 916                         wfQuery( $sql, DB_WRITE, $fname );
 917                 }
 918
 919                 # Note: the insert below must be after the updates above!
 920
 921                 # Now, we record the link from the redirect to the new title.
 922                 # It should have no other outgoing links...
 923                 $sql = "DELETE FROM links WHERE l_from={$newid}";
 924                 wfQuery( $sql, DB_WRITE, $fname );
 925                 $sql = "INSERT INTO links (l_from,l_to) VALUES ({$newid},{$oldid})";
 926                 wfQuery( $sql, DB_WRITE, $fname );
 927
 928                 # Purge squid
 929                 if ( $wgUseSquid ) {
 930                         $urls = array_merge( $nt->getSquidURLs(), $this->getSquidURLs() );
 931                         $u = new SquidUpdate( $urls );
 932                         $u->doUpdate();
 933                 }
 934         }
 935
 936         # Move page to non-existing title.
 937         # Sets $newid to be the new article ID
 938
 939         /* private */ function moveToNewTitle( &$nt, &$newid )
 940         {
 941                 global $wgUser, $wgLinkCache, $wgUseSquid;
 942                 $fname = "MovePageForm::moveToNewTitle";
 943                 $comment = wfMsg( "1movedto2", $this->getPrefixedText(), $nt->getPrefixedText() );
 944
 945                 $now = wfTimestampNow();
 946                 $won = wfInvertTimestamp( $now );
 947                 $newid = $nt->getArticleID();
 948                 $oldid = $this->getArticleID();
 949
 950                 # Rename cur entry
 951                 wfUpdateArray(
 952                         /* table */ 'cur',
 953                         /* SET */ array(
 954                                 'cur_touched' => $now,
 955                                 'cur_namespace' => $nt->getNamespace(),
 956                                 'cur_title' => $nt->getDBkey()
 957                         ),
 958                         /* WHERE */ array( 'cur_id' => $oldid ),
 959                         $fname
 960                 );
 961
 962                 $wgLinkCache->clearLink( $nt->getPrefixedDBkey() );
 963
 964                 # Insert redirct
 965                 wfInsertArray( 'cur', array(
 966                         'cur_namespace' => $this->getNamespace(),
 967                         'cur_title' => $this->getDBkey(),
 968                         'cur_comment' => $comment,
 969                         'cur_user' => $wgUser->getID(),
 970                         'cur_user_text' => $wgUser->getName(),
 971                         'cur_timestamp' => $now,
 972                         'inverse_timestamp' => $won,
 973                         'cur_touched' => $now,
 974                         'cur_is_redirect' => 1,
 975                         'cur_is_new' => 1,
 976                         'cur_text' => "#REDIRECT [[" . $nt->getPrefixedText() . "]]\n" )
 977                 );
 978                 $newid = wfInsertId();
 979                 $wgLinkCache->clearLink( $this->getPrefixedDBkey() );
 980
 981                 # Rename old entries
 982                 wfUpdateArray(
 983                         /* table */ 'old',
 984                         /* SET */ array(
 985                                 'old_namespace' => $nt->getNamespace(),
 986                                 'old_title' => $nt->getDBkey()
 987                         ),
 988                         /* WHERE */ array(
 989                                 'old_namespace' => $this->getNamespace(),
 990                                 'old_title' => $this->getDBkey()
 991                         ), $fname
 992                 );
 993
 994                 # Miscellaneous updates
 995
 996                 RecentChange::notifyMove( $now, $this, $nt, $wgUser, $comment );
 997                 Article::onArticleCreate( $nt );
 998
 999                 # Any text links to the old title must be reassigned to the redirect
1000                 $sql = "UPDATE links SET l_to={$newid} WHERE l_to={$oldid}";
1001                 wfQuery( $sql, DB_WRITE, $fname );
1002
1003                 # Record the just-created redirect's linking to the page
1004                 $sql = "INSERT INTO links (l_from,l_to) VALUES ({$newid},{$oldid})";
1005                 wfQuery( $sql, DB_WRITE, $fname );
1006
1007                 # Non-existent target may have had broken links to it; these must
1008                 # now be removed and made into good links.
1009                 $update = new LinksUpdate( $oldid, $nt->getPrefixedDBkey() );
1010                 $update->fixBrokenLinks();
1011
1012                 # Purge old title from squid
1013                 # The new title, and links to the new title, are purged in Article::onArticleCreate()
1014                 $titles = $nt->getLinksTo();
1015                 if ( $wgUseSquid ) {
1016                         $urls = $this->getSquidURLs();
1017                         foreach ( $titles as $linkTitle ) {
1018                                 $urls[] = $linkTitle->getInternalURL();
1019                         }
1020                         $u = new SquidUpdate( $urls );
1021                         $u->doUpdate();
1022                 }
1023         }
1024
1025         # Checks if $this can be moved to $nt
1026         # Both titles must exist in the database, otherwise it will blow up
1027         function isValidMoveTarget( $nt )
1028         {
1029                 $fname = "Title::isValidMoveTarget";
1030
1031                 # Is it a redirect?
1032                 $id  = $nt->getArticleID();
1033                 $sql = "SELECT cur_is_redirect,cur_text FROM cur " .
1034                   "WHERE cur_id={$id}";
1035                 $res = wfQuery( $sql, DB_READ, $fname );
1036                 $obj = wfFetchObject( $res );
1037
1038                 if ( 0 == $obj->cur_is_redirect ) {
1039                         # Not a redirect
1040                         return false;
1041                 }
1042
1043                 # Does the redirect point to the source?
1044                 if ( preg_match( "/\\[\\[\\s*([^\\]]*)]]/", $obj->cur_text, $m ) ) {
1045                         $redirTitle = Title::newFromText( $m[1] );
1046                         if ( 0 != strcmp( $redirTitle->getPrefixedDBkey(), $this->getPrefixedDBkey() ) ) {
1047                                 return false;
1048                         }
1049                 }
1050
1051                 # Does the article have a history?
1052                 $row = wfGetArray( 'old', array( 'old_id' ), array(
1053                         'old_namespace' => $nt->getNamespace(),
1054                         'old_title' => $nt->getDBkey() )
1055                 );
1056
1057                 # Return true if there was no history
1058                 return $row === false;
1059         }
1060
1061         # Create a redirect, fails if the title already exists, does not notify RC
1062         # Returns success
1063         function createRedirect( $dest, $comment ) {
1064                 global $wgUser;
1065                 if ( $this->getArticleID() ) {
1066                         return false;
1067                 }
1068
1069                 $now = wfTimestampNow();
1070                 $won = wfInvertTimestamp( $now );
1071
1072                 wfInsertArray( 'cur', array(
1073                         'cur_namespace' => $this->getNamespace(),
1074                         'cur_title' => $this->getDBkey(),
1075                         'cur_comment' => $comment,
1076                         'cur_user' => $wgUser->getID(),
1077                         'cur_user_text' => $wgUser->getName(),
1078                         'cur_timestamp' => $now,
1079                         'inverse_timestamp' => $won,
1080                         'cur_touched' => $now,
1081                         'cur_is_redirect' => 1,
1082                         'cur_is_new' => 1,
1083                         'cur_text' => "#REDIRECT [[" . $dest->getPrefixedText() . "]]\n"
1084                 ));
1085                 $newid = wfInsertId();
1086                 $this->resetArticleID( $newid );
1087
1088                 # Link table
1089                 if ( $dest->getArticleID() ) {
1090                         wfInsertArray( 'links', array(
1091                                 'l_to' => $dest->getArticleID(),
1092                                 'l_from' => $newid
1093                         ));
1094                 } else {
1095                         wfInsertArray( 'brokenlinks', array(
1096                                 'bl_to' => $dest->getPrefixedDBkey(),
1097                                 'bl_from' => $newid
1098                         ));
1099                 }
1100
1101                 Article::onArticleCreate( $this );
1102                 return true;
1103         }
1104 }
1105 ?>