includes/Title.php

   1 <?php
   2 # See title.doc
   3
   4 $wgTitleInterwikiCache = 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
  12 define ( 'GAID_FOR_UPDATE', 1 );
  13
  14 class Title {
  15         # All member variables should be considered private
  16         # Please use the accessor functions
  17
  18         var $mTextform;           # Text form (spaces not underscores) of the main part
  19         var $mUrlform;            # URL-encoded form of the main part
  20         var $mDbkeyform;          # Main part with underscores
  21         var $mNamespace;          # Namespace index, i.e. one of the NS_xxxx constants
  22         var $mInterwiki;          # Interwiki prefix (or null string)
  23         var $mFragment;           # Title fragment (i.e. the bit after the #)
  24         var $mArticleID;          # Article ID, fetched from the link cache on demand
  25         var $mRestrictions;       # Array of groups allowed to edit this article
  26                               # Only null or "sysop" are supported
  27         var $mRestrictionsLoaded; # Boolean for initialisation on demand
  28         var $mPrefixedText;       # Text form including namespace/interwiki, initialised on demand
  29         var $mDefaultNamespace;   # Namespace index when there is no namespace
  30                               # Zero except in {{transclusion}} tags
  31
  32 #----------------------------------------------------------------------------
  33 #   Construction
  34 #----------------------------------------------------------------------------
  35
  36         /* private */ function Title() {
  37                 $this->mInterwiki = $this->mUrlform =
  38                 $this->mTextform = $this->mDbkeyform = '';
  39                 $this->mArticleID = -1;
  40                 $this->mNamespace = 0;
  41                 $this->mRestrictionsLoaded = false;
  42                 $this->mRestrictions = array();
  43         $this->mDefaultNamespace = 0;
  44         }
  45
  46         # From a prefixed DB key
  47         /* static */ function newFromDBkey( $key ) {
  48                 $t = new Title();
  49                 $t->mDbkeyform = $key;
  50                 if( $t->secureAndSplit() )
  51                         return $t;
  52                 else
  53                         return NULL;
  54         }
  55
  56         # From text, such as what you would find in a link
  57         /* static */ function newFromText( $text, $defaultNamespace = 0 ) {
  58                 $fname = 'Title::newFromText';
  59                 wfProfileIn( $fname );
  60
  61                 if( is_object( $text ) ) {
  62                         wfDebugDieBacktrace( 'Called with object instead of string.' );
  63                 }
  64                 global $wgInputEncoding;
  65                 $text = do_html_entity_decode( $text, ENT_COMPAT, $wgInputEncoding );
  66
  67                 $text = wfMungeToUtf8( $text );
  68
  69
  70                 # What was this for? TS 2004-03-03
  71                 # $text = urldecode( $text );
  72
  73                 $t = new Title();
  74                 $t->mDbkeyform = str_replace( ' ', '_', $text );
  75                 $t->mDefaultNamespace = $defaultNamespace;
  76
  77                 wfProfileOut( $fname );
  78                 if ( !is_object( $t ) ) {
  79                         var_dump( debug_backtrace() );
  80                 }
  81                 if( $t->secureAndSplit() ) {
  82                         return $t;
  83                 } else {
  84                         return NULL;
  85                 }
  86         }
  87
  88         # From a URL-encoded title
  89         /* static */ function newFromURL( $url ) {
  90                 global $wgLang, $wgServer;
  91                 $t = new Title();
  92
  93                 # For compatibility with old buggy URLs. "+" is not valid in titles,
  94                 # but some URLs used it as a space replacement and they still come
  95                 # from some external search tools.
  96                 $s = str_replace( '+', ' ', $url );
  97
  98                 # For links that came from outside, check for alternate/legacy
  99                 # character encoding.
 100                 wfDebug( "Servr: $wgServer\n" );
 101                 if( empty( $_SERVER['HTTP_REFERER'] ) ||
 102                         strncmp($wgServer, $_SERVER['HTTP_REFERER'], strlen( $wgServer ) ) )
 103                 {
 104                         $s = $wgLang->checkTitleEncoding( $s );
 105                 } else {
 106                         wfDebug( "Refer: {$_SERVER['HTTP_REFERER']}\n" );
 107                 }
 108
 109                 $t->mDbkeyform = str_replace( ' ', '_', $s );
 110                 if( $t->secureAndSplit() ) {
 111                         # check that length of title is < cur_title size
 112                         $dbr =& wfGetDB( DB_SLAVE );
 113                         $maxSize = $dbr->textFieldSize( 'cur', 'cur_title' );
 114                         if ( $maxSize != -1 && strlen( $t->mDbkeyform ) > $maxSize ) {
 115                                 return NULL;
 116                         }
 117
 118                         return $t;
 119                 } else {
 120                         return NULL;
 121                 }
 122         }
 123
 124         # From a cur_id
 125         # This is inefficiently implemented, the cur row is requested but not
 126         # used for anything else
 127         /* static */ function newFromID( $id ) {
 128                 $fname = 'Title::newFromID';
 129                 $dbr =& wfGetDB( DB_SLAVE );
 130                 $row = $dbr->getArray( 'cur', array( 'cur_namespace', 'cur_title' ),
 131                         array( 'cur_id' => $id ), $fname );
 132                 if ( $row !== false ) {
 133                         $title = Title::makeTitle( $row->cur_namespace, $row->cur_title );
 134                 } else {
 135                         $title = NULL;
 136                 }
 137                 return $title;
 138         }
 139
 140         # From a namespace index and a DB key.
 141         # It's assumed that $ns and $title are *valid*, for instance when
 142         # they came directly from the database or a special page name.
 143         /* static */ function &makeTitle( $ns, $title ) {
 144                 $t =& new Title();
 145                 $t->mInterwiki = '';
 146                 $t->mFragment = '';
 147                 $t->mNamespace = $ns;
 148                 $t->mDbkeyform = $title;
 149                 $t->mArticleID = ( $ns >= 0 ) ? 0 : -1;
 150                 $t->mUrlform = wfUrlencode( $title );
 151                 $t->mTextform = str_replace( '_', ' ', $title );
 152                 return $t;
 153         }
 154
 155         # From a namespace index and a DB key.
 156         # These will be checked for validity, which is a bit slower
 157         # than makeTitle() but safer for user-provided data.
 158         /* static */ function makeTitleSafe( $ns, $title ) {
 159                 $t = new Title();
 160                 $t->mDbkeyform = Title::makeName( $ns, $title );
 161                 if( $t->secureAndSplit() ) {
 162                         return $t;
 163                 } else {
 164                         return NULL;
 165                 }
 166         }
 167
 168         /* static */ function newMainPage() {
 169                 return Title::newFromText( wfMsg( 'mainpage' ) );
 170         }
 171
 172         # Get the title object for a redirect
 173         # Returns NULL if the text is not a valid redirect
 174         /* static */ function newFromRedirect( $text ) {
 175                 global $wgMwRedir;
 176                 $rt = NULL;
 177                 if ( $wgMwRedir->matchStart( $text ) ) {
 178                         if ( preg_match( '/\\[\\[([^\\]\\|]+)[\\]\\|]/', $text, $m ) ) {
 179                                 # categories are escaped using : for example one can enter:
 180                                 # #REDIRECT [[:Category:Music]]. Need to remove it.
 181                                 if ( substr($m[1],0,1) == ':') {
 182                                         # We don't want to keep the ':'
 183                                         $m[1] = substr( $m[1], 1 );
 184                                 }
 185
 186                                 $rt = Title::newFromText( $m[1] );
 187                         }
 188                 }
 189                 return $rt;
 190         }
 191
 192 #----------------------------------------------------------------------------
 193 #       Static functions
 194 #----------------------------------------------------------------------------
 195
 196         # Get the prefixed DB key associated with an ID
 197         /* static */ function nameOf( $id ) {
 198                 $fname = 'Title::nameOf';
 199                 $dbr =& wfGetDB( DB_SLAVE );
 200
 201                 $s = $dbr->getArray( 'cur', array( 'cur_namespace','cur_title' ),  array( 'cur_id' => $id ), $fname );
 202                 if ( $s === false ) { return NULL; }
 203
 204                 $n = Title::makeName( $s->cur_namespace, $s->cur_title );
 205                 return $n;
 206         }
 207
 208         # Get a regex character class describing the legal characters in a link
 209         /* static */ function legalChars() {
 210                 # Missing characters:
 211                 #  * []|# Needed for link syntax
 212                 #  * % and + are corrupted by Apache when they appear in the path
 213                 #
 214                 # % seems to work though
 215                 #
 216                 # The problem with % is that URLs are double-unescaped: once by Apache's
 217                 # path conversion code, and again by PHP. So %253F, for example, becomes "?".
 218                 # Our code does not double-escape to compensate for this, indeed double escaping
 219                 # would break if the double-escaped title was passed in the query string
 220                 # rather than the path. This is a minor security issue because articles can be
 221                 # created such that they are hard to view or edit. -- TS
 222                 #
 223                 # Theoretically 0x80-0x9F of ISO 8859-1 should be disallowed, but
 224                 # this breaks interlanguage links
 225
 226                 $set = " %!\"$&'()*,\\-.\\/0-9:;=?@A-Z\\\\^_`a-z{}~\\x80-\\xFF";
 227                 return $set;
 228         }
 229
 230         # Returns a stripped-down a title string ready for the search index
 231         # Takes a namespace index and a text-form main part
 232         /* static */ function indexTitle( $ns, $title ) {
 233                 global $wgDBminWordLen, $wgLang;
 234                 require_once( 'SearchEngine.php' );
 235
 236                 $lc = SearchEngine::legalSearchChars() . '&#;';
 237                 $t = $wgLang->stripForSearch( $title );
 238                 $t = preg_replace( "/[^{$lc}]+/", ' ', $t );
 239                 $t = strtolower( $t );
 240
 241                 # Handle 's, s'
 242                 $t = preg_replace( "/([{$lc}]+)'s( |$)/", "\\1 \\1's ", $t );
 243                 $t = preg_replace( "/([{$lc}]+)s'( |$)/", "\\1s ", $t );
 244
 245                 $t = preg_replace( "/\\s+/", ' ', $t );
 246
 247                 if ( $ns == Namespace::getImage() ) {
 248                         $t = preg_replace( "/ (png|gif|jpg|jpeg|ogg)$/", "", $t );
 249                 }
 250                 return trim( $t );
 251         }
 252
 253         # Make a prefixed DB key from a DB key and a namespace index
 254         /* static */ function makeName( $ns, $title ) {
 255                 global $wgLang;
 256
 257                 $n = $wgLang->getNsText( $ns );
 258                 if ( '' == $n ) { return $title; }
 259                 else { return $n.':'.$title; }
 260         }
 261
 262         # Arguably static
 263         # Returns the URL associated with an interwiki prefix
 264         # The URL contains $1, which is replaced by the title
 265         function getInterwikiLink( $key ) {
 266                 global $wgMemc, $wgDBname, $wgInterwikiExpiry, $wgTitleInterwikiCache;
 267                 $fname = 'Title::getInterwikiLink';
 268                 $k = $wgDBname.':interwiki:'.$key;
 269
 270                 if( array_key_exists( $k, $wgTitleInterwikiCache ) )
 271                         return $wgTitleInterwikiCache[$k]->iw_url;
 272
 273                 $s = $wgMemc->get( $k );
 274                 # Ignore old keys with no iw_local
 275                 if( $s && isset( $s->iw_local ) ) {
 276                         $wgTitleInterwikiCache[$k] = $s;
 277                         return $s->iw_url;
 278                 }
 279                 $dbr =& wfGetDB( DB_SLAVE );
 280                 $res = $dbr->select( 'interwiki', array( 'iw_url', 'iw_local' ), array( 'iw_prefix' => $key ), $fname );
 281                 if(!$res) return '';
 282
 283                 $s = $dbr->fetchObject( $res );
 284                 if(!$s) {
 285                         # Cache non-existence: create a blank object and save it to memcached
 286                         $s = (object)false;
 287                         $s->iw_url = '';
 288                         $s->iw_local = 0;
 289                 }
 290                 $wgMemc->set( $k, $s, $wgInterwikiExpiry );
 291                 $wgTitleInterwikiCache[$k] = $s;
 292                 return $s->iw_url;
 293         }
 294
 295         function isLocal() {
 296                 global $wgTitleInterwikiCache, $wgDBname;
 297
 298                 if ( $this->mInterwiki != '' ) {
 299                         # Make sure key is loaded into cache
 300                         $this->getInterwikiLink( $this->mInterwiki );
 301                         $k = $wgDBname.':interwiki:' . $this->mInterwiki;
 302                         return (bool)($wgTitleInterwikiCache[$k]->iw_local);
 303                 } else {
 304                         return true;
 305                 }
 306         }
 307
 308         # Update the cur_touched field for an array of title objects
 309         # Inefficient unless the IDs are already loaded into the link cache
 310         /* static */ function touchArray( $titles, $timestamp = '' ) {
 311                 if ( count( $titles ) == 0 ) {
 312                         return;
 313                 }
 314                 if ( $timestamp == '' ) {
 315                         $timestamp = wfTimestampNow();
 316                 }
 317                 $dbw =& wfGetDB( DB_MASTER );
 318                 $cur = $dbw->tableName( 'cur' );
 319                 $sql = "UPDATE $cur SET cur_touched='{$timestamp}' WHERE cur_id IN (";
 320                 $first = true;
 321
 322                 foreach ( $titles as $title ) {
 323                         if ( ! $first ) {
 324                                 $sql .= ',';
 325                         }
 326                         $first = false;
 327                         $sql .= $title->getArticleID();
 328                 }
 329                 $sql .= ')';
 330                 if ( ! $first ) {
 331                         $dbw->query( $sql, 'Title::touchArray' );
 332                 }
 333         }
 334
 335 #----------------------------------------------------------------------------
 336 #       Other stuff
 337 #----------------------------------------------------------------------------
 338
 339         # Simple accessors
 340         # See the definitions at the top of this file
 341
 342         function getText() { return $this->mTextform; }
 343         function getPartialURL() { return $this->mUrlform; }
 344         function getDBkey() { return $this->mDbkeyform; }
 345         function getNamespace() { return $this->mNamespace; }
 346         function setNamespace( $n ) { $this->mNamespace = $n; }
 347         function getInterwiki() { return $this->mInterwiki; }
 348         function getFragment() { return $this->mFragment; }
 349         function getDefaultNamespace() { return $this->mDefaultNamespace; }
 350
 351         # Get title for search index
 352         function getIndexTitle() {
 353                 return Title::indexTitle( $this->mNamespace, $this->mTextform );
 354         }
 355
 356         # Get prefixed title with underscores
 357         function getPrefixedDBkey() {
 358                 $s = $this->prefix( $this->mDbkeyform );
 359                 $s = str_replace( ' ', '_', $s );
 360                 return $s;
 361         }
 362
 363         # Get prefixed title with spaces
 364         # This is the form usually used for display
 365         function getPrefixedText() {
 366                 if ( empty( $this->mPrefixedText ) ) {
 367                         $s = $this->prefix( $this->mTextform );
 368                         $s = str_replace( '_', ' ', $s );
 369                         $this->mPrefixedText = $s;
 370                 }
 371                 return $this->mPrefixedText;
 372         }
 373
 374         # As getPrefixedText(), plus fragment.
 375         function getFullText() {
 376                 $text = $this->getPrefixedText();
 377                 if( '' != $this->mFragment ) {
 378                         $text .= '#' . $this->mFragment;
 379                 }
 380                 return $text;
 381         }
 382
 383         # Get a URL-encoded title (not an actual URL) including interwiki
 384         function getPrefixedURL() {
 385                 $s = $this->prefix( $this->mDbkeyform );
 386                 $s = str_replace( ' ', '_', $s );
 387
 388                 $s = wfUrlencode ( $s ) ;
 389
 390                 # Cleaning up URL to make it look nice -- is this safe?
 391                 $s = preg_replace( '/%3[Aa]/', ':', $s );
 392                 $s = preg_replace( '/%2[Ff]/', '/', $s );
 393                 $s = str_replace( '%28', '(', $s );
 394                 $s = str_replace( '%29', ')', $s );
 395
 396                 return $s;
 397         }
 398
 399         # Get a real URL referring to this title, with interwiki link and fragment
 400         function getFullURL( $query = '' ) {
 401                 global $wgLang, $wgArticlePath, $wgServer, $wgScript;
 402
 403                 if ( '' == $this->mInterwiki ) {
 404                         $p = $wgArticlePath;
 405                         return $wgServer . $this->getLocalUrl( $query );
 406                 } else {
 407                         $baseUrl = $this->getInterwikiLink( $this->mInterwiki );
 408                         $namespace = $wgLang->getNsText( $this->mNamespace );
 409                         if ( '' != $namespace ) {
 410                                 # Can this actually happen? Interwikis shouldn't be parsed.
 411                                 $namepace .= ':';
 412                         }
 413                         $url = str_replace( '$1', $namespace . $this->mUrlform, $baseUrl );
 414                         if ( '' != $this->mFragment ) {
 415                                 $url .= '#' . $this->mFragment;
 416                         }
 417                         return $url;
 418                 }
 419         }
 420
 421         # Get a URL with an optional query string, no fragment
 422         # * If $query=="", it will use $wgArticlePath
 423         # * Returns a full for an interwiki link, loses any query string
 424         # * Optionally adds the server and escapes for HTML
 425         # * Setting $query to "-" makes an old-style URL with nothing in the
 426         #   query except a title
 427
 428         function getURL() {
 429                 die( 'Call to obsolete obsolete function Title::getURL()' );
 430         }
 431
 432         function getLocalURL( $query = '' ) {
 433                 global $wgLang, $wgArticlePath, $wgScript;
 434
 435                 if ( $this->isExternal() ) {
 436                         return $this->getFullURL();
 437                 }
 438
 439                 $dbkey = wfUrlencode( $this->getPrefixedDBkey() );
 440                 if ( $query == '' ) {
 441                         $url = str_replace( '$1', $dbkey, $wgArticlePath );
 442                 } else {
 443                         if ( $query == '-' ) {
 444                                 $query = '';
 445                         }
 446                         if ( $wgScript != '' ) {
 447                                 $url = "{$wgScript}?title={$dbkey}&{$query}";
 448                         } else {
 449                                 # Top level wiki
 450                                 $url = "/{$dbkey}?{$query}";
 451                         }
 452                 }
 453                 return $url;
 454         }
 455
 456         function escapeLocalURL( $query = '' ) {
 457                 return htmlspecialchars( $this->getLocalURL( $query ) );
 458         }
 459
 460         function escapeFullURL( $query = '' ) {
 461                 return htmlspecialchars( $this->getFullURL( $query ) );
 462         }
 463
 464         function getInternalURL( $query = '' ) {
 465                 # Used in various Squid-related code, in case we have a different
 466                 # internal hostname for the server than the exposed one.
 467                 global $wgInternalServer;
 468                 return $wgInternalServer . $this->getLocalURL( $query );
 469         }
 470
 471         # Get the edit URL, or a null string if it is an interwiki link
 472         function getEditURL() {
 473                 global $wgServer, $wgScript;
 474
 475                 if ( '' != $this->mInterwiki ) { return ''; }
 476                 $s = $this->getLocalURL( 'action=edit' );
 477
 478                 return $s;
 479         }
 480
 481         # Get HTML-escaped displayable text
 482         # For the title field in <a> tags
 483         function getEscapedText() {
 484                 return htmlspecialchars( $this->getPrefixedText() );
 485         }
 486
 487         # Is the title interwiki?
 488         function isExternal() { return ( '' != $this->mInterwiki ); }
 489
 490         # Does the title correspond to a protected article?
 491         function isProtected() {
 492                 if ( -1 == $this->mNamespace ) { return true; }
 493                 $a = $this->getRestrictions();
 494                 if ( in_array( 'sysop', $a ) ) { return true; }
 495                 return false;
 496         }
 497
 498         # Is the page a log page, i.e. one where the history is messed up by
 499         # LogPage.php? This used to be used for suppressing diff links in recent
 500         # changes, but now that's done by setting a flag in the recentchanges
 501         # table. Hence, this probably is no longer used.
 502         function isLog() {
 503                 if ( $this->mNamespace != Namespace::getWikipedia() ) {
 504                         return false;
 505                 }
 506                 if ( ( 0 == strcmp( wfMsg( 'uploadlogpage' ), $this->mDbkeyform ) ) ||
 507                   ( 0 == strcmp( wfMsg( 'dellogpage' ), $this->mDbkeyform ) ) ) {
 508                         return true;
 509                 }
 510                 return false;
 511         }
 512
 513         # Is $wgUser is watching this page?
 514         function userIsWatching() {
 515                 global $wgUser;
 516
 517                 if ( -1 == $this->mNamespace ) { return false; }
 518                 if ( 0 == $wgUser->getID() ) { return false; }
 519
 520                 return $wgUser->isWatched( $this );
 521         }
 522
 523         # Can $wgUser edit this page?
 524         function userCanEdit() {
 525                 global $wgUser;
 526                 if ( -1 == $this->mNamespace ) { return false; }
 527                 if ( NS_MEDIAWIKI == $this->mNamespace && !$wgUser->isSysop() ) { return false; }
 528                 # if ( 0 == $this->getArticleID() ) { return false; }
 529                 if ( $this->mDbkeyform == '_' ) { return false; }
 530                 # protect global styles and js
 531                 if ( NS_MEDIAWIKI == $this->mNamespace
 532                      && preg_match("/\\.(css|js)$/", $this->mTextform )
 533                      && !$wgUser->isSysop() )
 534                 { return false; }
 535                 //if ( $this->isCssJsSubpage() and !$this->userCanEditCssJsSubpage() ) { return false; }
 536                 # protect css/js subpages of user pages
 537                 # XXX: this might be better using restrictions
 538                 # XXX: Find a way to work around the php bug that prevents using $this->userCanEditCssJsSubpage() from working
 539                 if( Namespace::getUser() == $this->mNamespace
 540                         and preg_match("/\\.(css|js)$/", $this->mTextform )
 541                         and !$wgUser->isSysop()
 542                         and !preg_match('/^'.preg_quote($wgUser->getName(), '/').'/', $this->mTextform) )
 543                 { return false; }
 544                 $ur = $wgUser->getRights();
 545                 foreach ( $this->getRestrictions() as $r ) {
 546                         if ( '' != $r && ( ! in_array( $r, $ur ) ) ) {
 547                                 return false;
 548                         }
 549                 }
 550                 return true;
 551         }
 552
 553         function userCanRead() {
 554                 global $wgUser;
 555                 global $wgWhitelistRead;
 556
 557                 if( 0 != $wgUser->getID() ) return true;
 558                 if( !is_array( $wgWhitelistRead ) ) return true;
 559
 560                 $name = $this->getPrefixedText();
 561                 if( in_array( $name, $wgWhitelistRead ) ) return true;
 562
 563                 # Compatibility with old settings
 564                 if( $this->getNamespace() == NS_MAIN ) {
 565                         if( in_array( ':' . $name, $wgWhitelistRead ) ) return true;
 566                 }
 567                 return false;
 568         }
 569
 570         function isCssJsSubpage() {
 571                 return ( Namespace::getUser() == $this->mNamespace and preg_match("/\\.(css|js)$/", $this->mTextform ) );
 572         }
 573         function isCssSubpage() {
 574                 return ( Namespace::getUser() == $this->mNamespace and preg_match("/\\.css$/", $this->mTextform ) );
 575         }
 576         function isJsSubpage() {
 577                 return ( Namespace::getUser() == $this->mNamespace and preg_match("/\\.js$/", $this->mTextform ) );
 578         }
 579         function userCanEditCssJsSubpage() {
 580                 # protect css/js subpages of user pages
 581                 # XXX: this might be better using restrictions
 582                 global $wgUser;
 583                 return ( $wgUser->isSysop() or preg_match('/^'.preg_quote($wgUser->getName()).'/', $this->mTextform) );
 584         }
 585
 586         # Accessor/initialisation for mRestrictions
 587         function getRestrictions() {
 588                 $id = $this->getArticleID();
 589                 if ( 0 == $id ) { return array(); }
 590
 591                 if ( ! $this->mRestrictionsLoaded ) {
 592                         $dbr =& wfGetDB( DB_SLAVE );
 593                         $res = $dbr->getField( 'cur', 'cur_restrictions', 'cur_id='.$id );
 594                         $this->mRestrictions = explode( ',', trim( $res ) );
 595                         $this->mRestrictionsLoaded = true;
 596                 }
 597                 return $this->mRestrictions;
 598         }
 599
 600         # Is there a version of this page in the deletion archive?
 601         # Returns the number of archived revisions
 602         function isDeleted() {
 603                 $fname = 'Title::isDeleted';
 604                 $dbr =& wfGetDB( DB_SLAVE );
 605                 $n = $dbr->getField( 'archive', 'COUNT(*)', array( 'ar_namespace' => $this->getNamespace(),
 606                         'ar_title' => $this->getDBkey() ), $fname );
 607                 return (int)$n;
 608         }
 609
 610         # Get the article ID from the link cache
 611         # $flags is a bit field, may be GAID_FOR_UPDATE to select for update
 612         function getArticleID( $flags = 0 ) {
 613                 global $wgLinkCache;
 614
 615                 if ( $flags & GAID_FOR_UPDATE ) {
 616                         $oldUpdate = $wgLinkCache->forUpdate( true );
 617                         $this->mArticleID = $wgLinkCache->addLinkObj( $this );
 618                         $wgLinkCache->forUpdate( $oldUpdate );
 619                 } else {
 620                         if ( -1 == $this->mArticleID ) {
 621                                 $this->mArticleID = $wgLinkCache->addLinkObj( $this );
 622                         }
 623                 }
 624                 return $this->mArticleID;
 625         }
 626
 627         # This clears some fields in this object, and clears any associated keys in the
 628         # "bad links" section of $wgLinkCache. This is called from Article::insertNewArticle()
 629         # to allow loading of the new cur_id. It's also called from Article::doDeleteArticle()
 630         function resetArticleID( $newid ) {
 631                 global $wgLinkCache;
 632                 $wgLinkCache->clearBadLink( $this->getPrefixedDBkey() );
 633
 634                 if ( 0 == $newid ) { $this->mArticleID = -1; }
 635                 else { $this->mArticleID = $newid; }
 636                 $this->mRestrictionsLoaded = false;
 637                 $this->mRestrictions = array();
 638         }
 639
 640         # Updates cur_touched
 641         # Called from LinksUpdate.php
 642         function invalidateCache() {
 643                 $now = wfTimestampNow();
 644                 $dbw =& wfGetDB( DB_MASTER );
 645                 $success = $dbw->updateArray( 'cur',
 646                         array( /* SET */
 647                                 'cur_touched' => wfTimestampNow()
 648                         ), array( /* WHERE */
 649                                 'cur_namespace' => $this->getNamespace() ,
 650                                 'cur_title' => $this->getDBkey()
 651                         ), 'Title::invalidateCache'
 652                 );
 653                 return $success;
 654         }
 655
 656         # Prefixes some arbitrary text with the namespace or interwiki prefix of this object
 657         /* private */ function prefix( $name ) {
 658                 global $wgLang;
 659
 660                 $p = '';
 661                 if ( '' != $this->mInterwiki ) {
 662                         $p = $this->mInterwiki . ':';
 663                 }
 664                 if ( 0 != $this->mNamespace ) {
 665                         $p .= $wgLang->getNsText( $this->mNamespace ) . ':';
 666                 }
 667                 return $p . $name;
 668         }
 669
 670         # Secure and split - main initialisation function for this object
 671         #
 672         # Assumes that mDbkeyform has been set, and is urldecoded
 673     # and uses underscores, but not otherwise munged.  This function
 674     # removes illegal characters, splits off the interwiki and
 675     # namespace prefixes, sets the other forms, and canonicalizes
 676     # everything.
 677         #
 678         /* private */ function secureAndSplit()
 679         {
 680                 global $wgLang, $wgLocalInterwiki, $wgCapitalLinks;
 681                 $fname = 'Title::secureAndSplit';
 682                 wfProfileIn( $fname );
 683
 684                 static $imgpre = false;
 685                 static $rxTc = false;
 686
 687                 # Initialisation
 688                 if ( $imgpre === false ) {
 689                         $imgpre = ':' . $wgLang->getNsText( Namespace::getImage() ) . ':';
 690                         # % is needed as well
 691                         $rxTc = '/[^' . Title::legalChars() . ']/';
 692                 }
 693
 694                 $this->mInterwiki = $this->mFragment = '';
 695                 $this->mNamespace = $this->mDefaultNamespace; # Usually NS_MAIN
 696
 697                 # Clean up whitespace
 698                 #
 699                 $t = preg_replace( "/[\\s_]+/", '_', $this->mDbkeyform );
 700                 $t = preg_replace( '/^_*(.*?)_*$/', '$1', $t );
 701
 702                 if ( '' == $t ) {
 703                         wfProfileOut( $fname );
 704                         return false;
 705                 }
 706
 707                 $this->mDbkeyform = $t;
 708                 $done = false;
 709
 710                 # :Image: namespace
 711                 if ( 0 == strncasecmp( $imgpre, $t, strlen( $imgpre ) ) ) {
 712                         $t = substr( $t, 1 );
 713                 }
 714
 715                 # Initial colon indicating main namespace
 716                 if ( ':' == $t{0} ) {
 717                         $r = substr( $t, 1 );
 718                         $this->mNamespace = NS_MAIN;
 719                 } else {
 720                         # Namespace or interwiki prefix
 721                         if ( preg_match( "/^(.+?)_*:_*(.*)$/", $t, $m ) ) {
 722                                 #$p = strtolower( $m[1] );
 723                                 $p = $m[1];
 724                                 $lowerNs = strtolower( $p );
 725                                 if ( $ns = Namespace::getCanonicalIndex( $lowerNs ) ) {
 726                                         # Canonical namespace
 727                                         $t = $m[2];
 728                                         $this->mNamespace = $ns;
 729                                 } elseif ( $ns = $wgLang->getNsIndex( $lowerNs )) {
 730                                         # Ordinary namespace
 731                                         $t = $m[2];
 732                                         $this->mNamespace = $ns;
 733                                 } elseif ( $this->getInterwikiLink( $p ) ) {
 734                                         # Interwiki link
 735                                         $t = $m[2];
 736                                         $this->mInterwiki = $p;
 737
 738                                         if ( !preg_match( "/^([A-Za-z0-9_\\x80-\\xff]+):(.*)$/", $t, $m ) ) {
 739                                                 $done = true;
 740                                         } elseif($this->mInterwiki != $wgLocalInterwiki) {
 741                                                 $done = true;
 742                                         }
 743                                 }
 744                         }
 745                         $r = $t;
 746                 }
 747
 748                 # Redundant interwiki prefix to the local wiki
 749                 if ( 0 == strcmp( $this->mInterwiki, $wgLocalInterwiki ) ) {
 750                         $this->mInterwiki = '';
 751                 }
 752                 # We already know that some pages won't be in the database!
 753                 #
 754                 if ( '' != $this->mInterwiki || -1 == $this->mNamespace ) {
 755                         $this->mArticleID = 0;
 756                 }
 757                 $f = strstr( $r, '#' );
 758                 if ( false !== $f ) {
 759                         $this->mFragment = substr( $f, 1 );
 760                         $r = substr( $r, 0, strlen( $r ) - strlen( $f ) );
 761                 }
 762
 763                 # Reject illegal characters.
 764                 #
 765                 if( preg_match( $rxTc, $r ) ) {
 766                         wfProfileOut( $fname );
 767                         return false;
 768                 }
 769
 770                 # "." and ".." conflict with the directories of those namesa
 771                 if ( strpos( $r, '.' ) !== false &&
 772                      ( $r === '.' || $r === '..' ||
 773                        strpos( $r, './' ) === 0  ||
 774                        strpos( $r, '../' ) === 0 ||
 775                        strpos( $r, '/./' ) !== false ||
 776                        strpos( $r, '/../' ) !== false ) )
 777                 {
 778                         wfProfileOut( $fname );
 779                         return false;
 780                 }
 781
 782                 # Initial capital letter
 783                 if( $wgCapitalLinks && $this->mInterwiki == '') {
 784                         $t = $wgLang->ucfirst( $r );
 785                 } else {
 786                         $t = $r;
 787                 }
 788
 789                 # Fill fields
 790                 $this->mDbkeyform = $t;
 791                 $this->mUrlform = wfUrlencode( $t );
 792
 793                 $this->mTextform = str_replace( '_', ' ', $t );
 794
 795                 wfProfileOut( $fname );
 796                 return true;
 797         }
 798
 799         # Get a title object associated with the talk page of this article
 800         function getTalkPage() {
 801                 return Title::makeTitle( Namespace::getTalk( $this->getNamespace() ), $this->getDBkey() );
 802         }
 803
 804         # Get a title object associated with the subject page of this talk page
 805         function getSubjectPage() {
 806                 return Title::makeTitle( Namespace::getSubject( $this->getNamespace() ), $this->getDBkey() );
 807         }
 808
 809         # Get an array of Title objects linking to this title
 810         # Also stores the IDs in the link cache
 811         # $options may be FOR UPDATE
 812         function getLinksTo( $options = '' ) {
 813                 global $wgLinkCache;
 814                 $id = $this->getArticleID();
 815
 816                 if ( $options ) {
 817                         $db =& wfGetDB( DB_MASTER );
 818                 } else {
 819                         $db =& wfGetDB( DB_SLAVE );
 820                 }
 821                 $cur = $db->tableName( 'cur' );
 822                 $links = $db->tableName( 'links' );
 823
 824                 $sql = "SELECT cur_namespace,cur_title,cur_id FROM $cur,$links WHERE l_from=cur_id AND l_to={$id} $options";
 825                 $res = $db->query( $sql, 'Title::getLinksTo' );
 826                 $retVal = array();
 827                 if ( $db->numRows( $res ) ) {
 828                         while ( $row = $db->fetchObject( $res ) ) {
 829                                 if ( $titleObj = Title::makeTitle( $row->cur_namespace, $row->cur_title ) ) {
 830                                         $wgLinkCache->addGoodLink( $row->cur_id, $titleObj->getPrefixedDBkey() );
 831                                         $retVal[] = $titleObj;
 832                                 }
 833                         }
 834                 }
 835                 $db->freeResult( $res );
 836                 return $retVal;
 837         }
 838
 839         # Get an array of Title objects linking to this non-existent title
 840         # Also stores the IDs in the link cache
 841         function getBrokenLinksTo( $options = '' ) {
 842                 global $wgLinkCache;
 843
 844                 if ( $options ) {
 845                         $db =& wfGetDB( DB_MASTER );
 846                 } else {
 847                         $db =& wfGetDB( DB_SLAVE );
 848                 }
 849                 $cur = $db->tableName( 'cur' );
 850                 $brokenlinks = $db->tableName( 'brokenlinks' );
 851                 $encTitle = $db->strencode( $this->getPrefixedDBkey() );
 852
 853                 $sql = "SELECT cur_namespace,cur_title,cur_id FROM $brokenlinks,$cur " .
 854                   "WHERE bl_from=cur_id AND bl_to='$encTitle' $options";
 855                 $res = $db->query( $sql, "Title::getBrokenLinksTo" );
 856                 $retVal = array();
 857                 if ( $db->numRows( $res ) ) {
 858                         while ( $row = $db->fetchObject( $res ) ) {
 859                                 $titleObj = Title::makeTitle( $row->cur_namespace, $row->cur_title );
 860                                 $wgLinkCache->addGoodLink( $row->cur_id, $titleObj->getPrefixedDBkey() );
 861                                 $retVal[] = $titleObj;
 862                         }
 863                 }
 864                 $db->freeResult( $res );
 865                 return $retVal;
 866         }
 867
 868         function getSquidURLs() {
 869                 return array(
 870                         $this->getInternalURL(),
 871                         $this->getInternalURL( 'action=history' )
 872                 );
 873         }
 874
 875         function moveNoAuth( &$nt ) {
 876                 return $this->moveTo( $nt, false );
 877         }
 878
 879         # Move a title to a new location
 880         # Returns true on success, message name on failure
 881         # auth indicates whether wgUser's permissions should be checked
 882         function moveTo( &$nt, $auth = true ) {
 883                 if( !$this or !$nt ) {
 884                         return 'badtitletext';
 885                 }
 886
 887                 $fname = 'Title::move';
 888                 $oldid = $this->getArticleID();
 889                 $newid = $nt->getArticleID();
 890
 891                 if ( strlen( $nt->getDBkey() ) < 1 ) {
 892                         return 'articleexists';
 893                 }
 894                 if ( ( ! Namespace::isMovable( $this->getNamespace() ) ) ||
 895                          ( '' == $this->getDBkey() ) ||
 896                          ( '' != $this->getInterwiki() ) ||
 897                          ( !$oldid ) ||
 898                      ( ! Namespace::isMovable( $nt->getNamespace() ) ) ||
 899                          ( '' == $nt->getDBkey() ) ||
 900                          ( '' != $nt->getInterwiki() ) ) {
 901                         return 'badarticleerror';
 902                 }
 903
 904                 if ( $auth && ( !$this->userCanEdit() || !$nt->userCanEdit() ) ) {
 905                         return 'protectedpage';
 906                 }
 907
 908                 # The move is allowed only if (1) the target doesn't exist, or
 909                 # (2) the target is a redirect to the source, and has no history
 910                 # (so we can undo bad moves right after they're done).
 911
 912                 if ( 0 != $newid ) { # Target exists; check for validity
 913                         if ( ! $this->isValidMoveTarget( $nt ) ) {
 914                                 return 'articleexists';
 915                         }
 916                         $this->moveOverExistingRedirect( $nt );
 917                 } else { # Target didn't exist, do normal move.
 918                         $this->moveToNewTitle( $nt, $newid );
 919                 }
 920
 921                 # Fixing category links (those without piped 'alternate' names) to be sorted under the new title
 922
 923                 $dbw =& wfGetDB( DB_MASTER );
 924                 $sql = "UPDATE categorylinks SET cl_sortkey=" . $dbw->addQuotes( $nt->getPrefixedText() ) .
 925                         " WHERE cl_from=" . $dbw->addQuotes( $this->getArticleID() ) .
 926                         " AND cl_sortkey=" . $dbw->addQuotes( $this->getPrefixedText() );
 927                 $dbw->query( $sql, 'SpecialMovepage::doSubmit' );
 928
 929                 # Update watchlists
 930
 931                 $oldnamespace = $this->getNamespace() & ~1;
 932                 $newnamespace = $nt->getNamespace() & ~1;
 933                 $oldtitle = $this->getDBkey();
 934                 $newtitle = $nt->getDBkey();
 935
 936                 if( $oldnamespace != $newnamespace || $oldtitle != $newtitle ) {
 937                         WatchedItem::duplicateEntries( $this, $nt );
 938                 }
 939
 940                 # Update search engine
 941                 $u = new SearchUpdate( $oldid, $nt->getPrefixedDBkey() );
 942                 $u->doUpdate();
 943                 $u = new SearchUpdate( $newid, $this->getPrefixedDBkey(), '' );
 944                 $u->doUpdate();
 945
 946                 return true;
 947         }
 948
 949         # Move page to title which is presently a redirect to the source page
 950
 951         /* private */ function moveOverExistingRedirect( &$nt ) {
 952                 global $wgUser, $wgLinkCache, $wgUseSquid, $wgMwRedir;
 953                 $fname = 'Title::moveOverExistingRedirect';
 954                 $comment = wfMsg( '1movedto2', $this->getPrefixedText(), $nt->getPrefixedText() );
 955
 956         $now = wfTimestampNow();
 957         $won = wfInvertTimestamp( $now );
 958                 $newid = $nt->getArticleID();
 959                 $oldid = $this->getArticleID();
 960                 $dbw =& wfGetDB( DB_MASTER );
 961                 $links = $dbw->tableName( 'links' );
 962
 963                 # Change the name of the target page:
 964                 $dbw->updateArray( 'cur',
 965                         /* SET */ array(
 966                                 'cur_touched' => $now,
 967                                 'cur_namespace' => $nt->getNamespace(),
 968                                 'cur_title' => $nt->getDBkey()
 969                         ),
 970                         /* WHERE */ array( 'cur_id' => $oldid ),
 971                         $fname
 972                 );
 973                 $wgLinkCache->clearLink( $nt->getPrefixedDBkey() );
 974
 975                 # Repurpose the old redirect. We don't save it to history since
 976                 # by definition if we've got here it's rather uninteresting.
 977
 978                 $redirectText = $wgMwRedir->getSynonym( 0 ) . ' [[' . $nt->getPrefixedText() . "]]\n";
 979                 $dbw->updateArray( 'cur',
 980                         /* SET */ array(
 981                                 'cur_touched' => $now,
 982                                 'cur_timestamp' => $now,
 983                                 'inverse_timestamp' => $won,
 984                                 'cur_namespace' => $this->getNamespace(),
 985                                 'cur_title' => $this->getDBkey(),
 986                                 'cur_text' => $wgMwRedir->getSynonym( 0 ) . ' [[' . $nt->getPrefixedText() . "]]\n",
 987                                 'cur_comment' => $comment,
 988                                 'cur_user' => $wgUser->getID(),
 989                                 'cur_minor_edit' => 0,
 990                                 'cur_counter' => 0,
 991                                 'cur_restrictions' => '',
 992                                 'cur_user_text' => $wgUser->getName(),
 993                                 'cur_is_redirect' => 1,
 994                                 'cur_is_new' => 1
 995                         ),
 996                         /* WHERE */ array( 'cur_id' => $newid ),
 997                         $fname
 998                 );
 999
1000                 $wgLinkCache->clearLink( $this->getPrefixedDBkey() );
1001
1002                 # Fix the redundant names for the past revisions of the target page.
1003                 # The redirect should have no old revisions.
1004                 $dbw->updateArray(
1005                         /* table */ 'old',
1006                         /* SET */ array(
1007                                 'old_namespace' => $nt->getNamespace(),
1008                                 'old_title' => $nt->getDBkey(),
1009                         ),
1010                         /* WHERE */ array(
1011                                 'old_namespace' => $this->getNamespace(),
1012                                 'old_title' => $this->getDBkey(),
1013                         ),
1014                         $fname
1015                 );
1016
1017                 RecentChange::notifyMoveOverRedirect( $now, $this, $nt, $wgUser, $comment );
1018
1019                 # Swap links
1020
1021                 # Load titles and IDs
1022                 $linksToOld = $this->getLinksTo( 'FOR UPDATE' );
1023                 $linksToNew = $nt->getLinksTo( 'FOR UPDATE' );
1024
1025                 # Delete them all
1026                 $sql = "DELETE FROM $links WHERE l_to=$oldid OR l_to=$newid";
1027                 $dbw->query( $sql, $fname );
1028
1029                 # Reinsert
1030                 if ( count( $linksToOld ) || count( $linksToNew )) {
1031                         $sql = "INSERT INTO $links (l_from,l_to) VALUES ";
1032                         $first = true;
1033
1034                         # Insert links to old title
1035                         foreach ( $linksToOld as $linkTitle ) {
1036                                 if ( $first ) {
1037                                         $first = false;
1038                                 } else {
1039                                         $sql .= ',';
1040                                 }
1041                                 $id = $linkTitle->getArticleID();
1042                                 $sql .= "($id,$newid)";
1043                         }
1044
1045                         # Insert links to new title
1046                         foreach ( $linksToNew as $linkTitle ) {
1047                                 if ( $first ) {
1048                                         $first = false;
1049                                 } else {
1050                                         $sql .= ',';
1051                                 }
1052                                 $id = $linkTitle->getArticleID();
1053                                 $sql .= "($id, $oldid)";
1054                         }
1055
1056                         $dbw->query( $sql, DB_MASTER, $fname );
1057                 }
1058
1059                 # Now, we record the link from the redirect to the new title.
1060                 # It should have no other outgoing links...
1061                 $dbw->delete( 'links', array( 'l_from' => $newid ) );
1062                 $dbw->insertArray( 'links', array( 'l_from' => $newid, 'l_to' => $oldid ) );
1063
1064                 # Clear linkscc
1065                 LinkCache::linksccClearLinksTo( $oldid );
1066                 LinkCache::linksccClearLinksTo( $newid );
1067
1068                 # Purge squid
1069                 if ( $wgUseSquid ) {
1070                         $urls = array_merge( $nt->getSquidURLs(), $this->getSquidURLs() );
1071                         $u = new SquidUpdate( $urls );
1072                         $u->doUpdate();
1073                 }
1074         }
1075
1076         # Move page to non-existing title.
1077         # Sets $newid to be the new article ID
1078
1079         /* private */ function moveToNewTitle( &$nt, &$newid ) {
1080                 global $wgUser, $wgLinkCache, $wgUseSquid;
1081                 $fname = 'MovePageForm::moveToNewTitle';
1082                 $comment = wfMsg( '1movedto2', $this->getPrefixedText(), $nt->getPrefixedText() );
1083
1084                 $now = wfTimestampNow();
1085                 $won = wfInvertTimestamp( $now );
1086                 $newid = $nt->getArticleID();
1087                 $oldid = $this->getArticleID();
1088                 $dbw =& wfGetDB( DB_MASTER );
1089
1090                 # Rename cur entry
1091                 $dbw->updateArray( 'cur',
1092                         /* SET */ array(
1093                                 'cur_touched' => $now,
1094                                 'cur_namespace' => $nt->getNamespace(),
1095                                 'cur_title' => $nt->getDBkey()
1096                         ),
1097                         /* WHERE */ array( 'cur_id' => $oldid ),
1098                         $fname
1099                 );
1100
1101                 $wgLinkCache->clearLink( $nt->getPrefixedDBkey() );
1102
1103                 # Insert redirct
1104                 $dbw->insertArray( 'cur', array(
1105                         'cur_namespace' => $this->getNamespace(),
1106                         'cur_title' => $this->getDBkey(),
1107                         'cur_comment' => $comment,
1108                         'cur_user' => $wgUser->getID(),
1109                         'cur_user_text' => $wgUser->getName(),
1110                         'cur_timestamp' => $now,
1111                         'inverse_timestamp' => $won,
1112                         'cur_touched' => $now,
1113                         'cur_is_redirect' => 1,
1114                         'cur_is_new' => 1,
1115                         'cur_text' => "#REDIRECT [[" . $nt->getPrefixedText() . "]]\n" ), $fname
1116                 );
1117                 $newid = $dbw->insertId();
1118                 $wgLinkCache->clearLink( $this->getPrefixedDBkey() );
1119
1120                 # Rename old entries
1121                 $dbw->updateArray(
1122                         /* table */ 'old',
1123                         /* SET */ array(
1124                                 'old_namespace' => $nt->getNamespace(),
1125                                 'old_title' => $nt->getDBkey()
1126                         ),
1127                         /* WHERE */ array(
1128                                 'old_namespace' => $this->getNamespace(),
1129                                 'old_title' => $this->getDBkey()
1130                         ), $fname
1131                 );
1132
1133                 # Record in RC
1134                 RecentChange::notifyMoveToNew( $now, $this, $nt, $wgUser, $comment );
1135
1136                 # Purge squid and linkscc as per article creation
1137                 Article::onArticleCreate( $nt );
1138
1139                 # Any text links to the old title must be reassigned to the redirect
1140                 $dbw->updateArray( 'links', array( 'l_to' => $newid ), array( 'l_to' => $oldid ), $fname );
1141                 LinkCache::linksccClearLinksTo( $oldid );
1142
1143                 # Record the just-created redirect's linking to the page
1144                 $dbw->insertArray( 'links', array( 'l_from' => $newid, 'l_to' => $oldid ), $fname );
1145
1146                 # Non-existent target may have had broken links to it; these must
1147                 # now be removed and made into good links.
1148                 $update = new LinksUpdate( $oldid, $nt->getPrefixedDBkey() );
1149                 $update->fixBrokenLinks();
1150
1151                 # Purge old title from squid
1152                 # The new title, and links to the new title, are purged in Article::onArticleCreate()
1153                 $titles = $nt->getLinksTo();
1154                 if ( $wgUseSquid ) {
1155                         $urls = $this->getSquidURLs();
1156                         foreach ( $titles as $linkTitle ) {
1157                                 $urls[] = $linkTitle->getInternalURL();
1158                         }
1159                         $u = new SquidUpdate( $urls );
1160                         $u->doUpdate();
1161                 }
1162         }
1163
1164         # Checks if $this can be moved to $nt
1165         # Selects for update, so don't call it unless you mean business
1166         function isValidMoveTarget( $nt ) {
1167                 $fname = 'Title::isValidMoveTarget';
1168                 $dbw =& wfGetDB( DB_MASTER );
1169
1170                 # Is it a redirect?
1171                 $id  = $nt->getArticleID();
1172                 $obj = $dbw->getArray( 'cur', array( 'cur_is_redirect','cur_text' ),
1173                         array( 'cur_id' => $id ), $fname, 'FOR UPDATE' );
1174
1175                 if ( !$obj || 0 == $obj->cur_is_redirect ) {
1176                         # Not a redirect
1177                         return false;
1178                 }
1179
1180                 # Does the redirect point to the source?
1181                 if ( preg_match( "/\\[\\[\\s*([^\\]\\|]*)]]/", $obj->cur_text, $m ) ) {
1182                         $redirTitle = Title::newFromText( $m[1] );
1183                         if( !is_object( $redirTitle ) ||
1184                                 $redirTitle->getPrefixedDBkey() != $this->getPrefixedDBkey() ) {
1185                                 return false;
1186                         }
1187                 }
1188
1189                 # Does the article have a history?
1190                 $row = $dbw->getArray( 'old', array( 'old_id' ),
1191                         array(
1192                                 'old_namespace' => $nt->getNamespace(),
1193                                 'old_title' => $nt->getDBkey()
1194                         ), $fname, 'FOR UPDATE'
1195                 );
1196
1197                 # Return true if there was no history
1198                 return $row === false;
1199         }
1200
1201         # Create a redirect, fails if the title already exists, does not notify RC
1202         # Returns success
1203         function createRedirect( $dest, $comment ) {
1204                 global $wgUser;
1205                 if ( $this->getArticleID() ) {
1206                         return false;
1207                 }
1208
1209                 $fname = 'Title::createRedirect';
1210                 $dbw =& wfGetDB( DB_MASTER );
1211                 $now = wfTimestampNow();
1212                 $won = wfInvertTimestamp( $now );
1213                 $seqVal = $dbw->nextSequenceValue( 'cur_cur_id_seq' );
1214
1215                 $dbw->insertArray( 'cur', array(
1216                         'cur_id' => $seqVal,
1217                         'cur_namespace' => $this->getNamespace(),
1218                         'cur_title' => $this->getDBkey(),
1219                         'cur_comment' => $comment,
1220                         'cur_user' => $wgUser->getID(),
1221                         'cur_user_text' => $wgUser->getName(),
1222                         'cur_timestamp' => $now,
1223                         'inverse_timestamp' => $won,
1224                         'cur_touched' => $now,
1225                         'cur_is_redirect' => 1,
1226                         'cur_is_new' => 1,
1227                         'cur_text' => "#REDIRECT [[" . $dest->getPrefixedText() . "]]\n"
1228                 ), $fname );
1229                 $newid = $dbw->insertId();
1230                 $this->resetArticleID( $newid );
1231
1232                 # Link table
1233                 if ( $dest->getArticleID() ) {
1234                         $dbw->insertArray( 'links',
1235                                 array(
1236                                         'l_to' => $dest->getArticleID(),
1237                                         'l_from' => $newid
1238                                 ), $fname
1239                         );
1240                 } else {
1241                         $dbw->insertArray( 'brokenlinks',
1242                                 array(
1243                                         'bl_to' => $dest->getPrefixedDBkey(),
1244                                         'bl_from' => $newid
1245                                 ), $fname
1246                         );
1247                 }
1248
1249                 Article::onArticleCreate( $this );
1250                 return true;
1251         }
1252
1253         # Get categories to wich belong this title and return an array of
1254         # categories names.
1255         function getParentCategories( ) {
1256                 global $wgLang,$wgUser;
1257
1258                 $titlekey = $this->getArticleId();
1259                 $cns = Namespace::getCategory();
1260                 $sk =& $wgUser->getSkin();
1261                 $parents = array();
1262                 $dbr =& wfGetDB( DB_SLAVE );
1263                 $cur = $dbr->tableName( 'cur' );
1264                 $categorylinks = $dbr->tableName( 'categorylinks' );
1265
1266                 # get the parents categories of this title from the database
1267                 $sql = "SELECT DISTINCT cur_id FROM $cur,$categorylinks
1268                         WHERE cl_from='$titlekey' AND cl_to=cur_title AND cur_namespace='$cns'
1269                                 ORDER BY cl_sortkey" ;
1270                 $res = $dbr->query ( $sql ) ;
1271
1272                 if($dbr->numRows($res) > 0) {
1273                         while ( $x = $dbr->fetchObject ( $res ) ) $data[] = $x ;
1274                         $dbr->freeResult ( $res ) ;
1275                 } else {
1276                         $data = '';
1277                 }
1278                 return $data;
1279         }
1280
1281         # will get the parents and grand-parents
1282         # TODO : not sure what's happening when a loop happen like:
1283         #       Encyclopedia > Astronomy > Encyclopedia
1284         function getAllParentCategories(&$stack) {
1285                 global $wgUser,$wgLang;
1286                 $result = '';
1287
1288                 # getting parents
1289                 $parents = $this->getParentCategories( );
1290
1291                 if($parents == '')
1292                 {
1293                         # The current element has no more parent so we dump the stack
1294                         # and make a clean line of categories
1295                         $sk =& $wgUser->getSkin() ;
1296
1297                         foreach ( array_reverse($stack) as $child => $parent )
1298                         {
1299                                 # make a link of that parent
1300                                 $result .= $sk->makeLink($wgLang->getNSText ( Namespace::getCategory() ).':'.$parent,$parent);
1301                                 $result .= ' &gt; ';
1302                                 $lastchild = $child;
1303                         }
1304                         # append the last child.
1305                         # TODO : We should have a last child unless there is an error in the
1306                         # "categorylinks" table.
1307                         if(isset($lastchild)) { $result .= $lastchild; }
1308
1309                         $result .= "<br/>\n";
1310
1311                         # now we can empty the stack
1312                         $stack = array();
1313
1314                 } else {
1315                         # look at parents of current category
1316                         foreach($parents as $parent)
1317                         {
1318                                 # create a title object for the parent
1319                                 $tpar = Title::newFromID($parent->cur_id);
1320                                 # add it to the stack
1321                                 $stack[$this->getText()] = $tpar->getText();
1322                                 # grab its parents
1323                                 $result .= $tpar->getAllParentCategories($stack);
1324                         }
1325                 }
1326
1327                 if(isset($result)) { return $result; }
1328                 else { return ''; };
1329         }
1330
1331         # Returns an associative array for selecting this title from cur
1332         function curCond() {
1333                 return array( 'cur_namespace' => $this->mNamespace, 'cur_title' => $this->mDbkeyform );
1334         }
1335
1336         function oldCond() {
1337                 return array( 'old_namespace' => $this->mNamespace, 'old_title' => $this->mDbkeyform );
1338         }
1339 }
1340 ?>