includes/SearchEngine.php

   1 <?php
   2 /**
   3  * Contain site class
   4  * See search.doc
   5  */
   6
   7 /**
   8  *
   9  */
  10 define( 'MW_SEARCH_OK', true );
  11 define( 'MW_SEARCH_BAD_QUERY', false );
  12
  13 /**
  14  * @todo document
  15  */
  16 class SearchEngine {
  17         /* private */ var $rawText, $filteredText, $searchTerms;
  18         /* private */ var $titleCond, $textCond;
  19
  20         var $doSearchRedirects = true;
  21         var $addToQuery = array();
  22         var $namespacesToSearch = array();
  23         var $alternateTitle;
  24         var $allTitles = false;
  25
  26         function SearchEngine( $text ) {
  27                 $this->rawText = trim( $text );
  28
  29                 # We display the query, so let's strip it for safety
  30                 #
  31                 global $wgDBmysql4;
  32                 $lc = SearchEngine::legalSearchChars() . '()';
  33                 if( $wgDBmysql4 ) {
  34                         $lc .= "\"~<>*+-";
  35                 }
  36                 $this->filteredText = trim( preg_replace( "/[^{$lc}]/", " ", $text ) );
  37                 $this->searchTerms = array();
  38                 $this->strictMatching = true; # Google-style, add '+' on all terms
  39
  40                 $this->db =& wfGetDB( DB_SLAVE );
  41         }
  42
  43         /**
  44          * Return a partial WHERE clause to limit the search to the given namespaces
  45          */
  46         function queryNamespaces() {
  47                 $namespaces = implode( ',', $this->namespacesToSearch );
  48                 if ($namespaces == '') {
  49                         $namespaces = '0';
  50                 }
  51                 return "AND cur_namespace IN (" . $namespaces . ')';
  52         }
  53
  54         /**
  55          * Return a partial WHERE clause to include or exclude redirects from results
  56          */
  57         function searchRedirects() {
  58                 if ( $this->doSearchRedirects ) {
  59                         return '';
  60                 } else {
  61                         return 'AND cur_is_redirect=0 ';
  62                 }
  63         }
  64
  65         /**
  66          * @access private
  67          */ function initNamespaceCheckbox( $i ) {
  68                 global $wgUser, $wgNamespacesToBeSearchedDefault;
  69
  70                 if ($wgUser->getID()) {
  71                         // User is logged in so we retrieve his default namespaces
  72                         return $wgUser->getOption( 'searchNs'.$i );
  73                 } else {
  74                         // User is not logged in so we give him the global default namespaces
  75                         return !empty($wgNamespacesToBeSearchedDefault[ $i ]);
  76                 }
  77         }
  78
  79         /**
  80          * Display the "power search" footer. Does not actually perform the search,
  81          * that is done by showResults()
  82          */
  83         function powersearch() {
  84                 global $wgUser, $wgOut, $wgLang, $wgTitle, $wgRequest;
  85                 $sk =& $wgUser->getSkin();
  86
  87                 $search                 = $this->rawText;
  88                 $searchx                = $wgRequest->getVal( 'searchx' );
  89                 $listredirs             = $wgRequest->getVal( 'redirs' );
  90
  91                 $ret = wfMsg('powersearchtext'); # Text to be returned
  92                 $tempText = ''; # Temporary text, for substitution into $ret
  93
  94                 if( isset( $_REQUEST['searchx'] ) ) {
  95                         $this->addToQuery['searchx'] = '1';
  96                 }
  97
  98                 # Do namespace checkboxes
  99                 $namespaces = $wgLang->getNamespaces();
 100                 foreach ( $namespaces as $i => $namespace ) {
 101                         # Skip virtual namespaces
 102                         if ( $i < 0 ) {
 103                                 continue;
 104                         }
 105
 106                         $formVar = 'ns'.$i;
 107
 108                         # Initialise checkboxValues, either from defaults or from
 109                         # a previous invocation
 110                         if ( !isset( $searchx ) ) {
 111                                 $checkboxValue = $this->initNamespaceCheckbox( $i );
 112                         } else {
 113                                 $checkboxValue = $wgRequest->getVal( $formVar );
 114                         }
 115
 116                         $checked = '';
 117                         if ( $checkboxValue == 1 ) {
 118                                 $checked = ' checked="checked"';
 119                                 $this->addToQuery['ns'.$i] = 1;
 120                                 array_push( $this->namespacesToSearch, $i );
 121                         }
 122                         $name = str_replace( '_', ' ', $namespaces[$i] );
 123                         if ( '' == $name ) {
 124                                 $name = wfMsg( 'blanknamespace' );
 125                         }
 126
 127                         if ( $tempText !== '' ) {
 128                                 $tempText .= ' ';
 129                         }
 130                         $tempText .= "<input type='checkbox' value=\"1\" name=\"" .
 131                           "ns{$i}\"{$checked} />{$name}\n";
 132                 }
 133                 $ret = str_replace ( '$1', $tempText, $ret );
 134
 135                 # List redirects checkbox
 136
 137                 $checked = '';
 138                 if ( $listredirs == 1 ) {
 139                         $this->addToQuery['redirs'] = 1;
 140                         $checked = ' checked="checked"';
 141                 }
 142                 $tempText = "<input type='checkbox' value='1' name=\"redirs\"{$checked} />\n";
 143                 $ret = str_replace( '$2', $tempText, $ret );
 144
 145                 # Search field
 146
 147                 $tempText = "<input type='text' name=\"search\" value=\"" .
 148                         htmlspecialchars( $search ) ."\" width=\"80\" />\n";
 149         $ret = str_replace( "$3", $tempText, $ret );
 150
 151                 # Searchx button
 152
 153                 $tempText = '<input type="submit" name="searchx" value="' .
 154                   wfMsg('powersearch') . "\" />\n";
 155                 $ret = str_replace( '$9', $tempText, $ret );
 156
 157                 $action = $sk->escapeSearchLink();
 158                 $ret = "<br /><br />\n<form id=\"powersearch\" method=\"get\" " .
 159                   "action=\"$action\">\n{$ret}\n</form>\n";
 160
 161                 if ( isset ( $searchx ) ) {
 162                         if ( ! $listredirs ) {
 163                                 $this->doSearchRedirects = false;
 164                         }
 165                 }
 166                 return $ret;
 167         }
 168
 169         function setupPage() {
 170                 global $wgOut;
 171                 $wgOut->setPageTitle( wfMsg( 'searchresults' ) );
 172                 $wgOut->setSubtitle( wfMsg( 'searchquery', htmlspecialchars( $this->rawText ) ) );
 173                 $wgOut->setArticleRelated( false );
 174                 $wgOut->setRobotpolicy( 'noindex,nofollow' );
 175         }
 176
 177         /**
 178          * Perform the search and construct the results page
 179          */
 180         function showResults() {
 181                 global $wgUser, $wgTitle, $wgOut, $wgLang;
 182                 global $wgDisableTextSearch, $wgInputEncoding;
 183                 $fname = 'SearchEngine::showResults';
 184
 185                 $search = $this->rawText;
 186
 187                 $powersearch = $this->powersearch(); /* Need side-effects here? */
 188
 189                 $this->setupPage();
 190
 191                 $sk = $wgUser->getSkin();
 192                 $wgOut->addWikiText( wfMsg( 'searchresulttext' ) );
 193
 194                 if ( !$this->parseQuery() ) {
 195                         $wgOut->addWikiText(
 196                                 '==' . wfMsg( 'badquery' ) . "==\n" .
 197                                 wfMsg( 'badquerytext' ) );
 198                         return;
 199                 }
 200                 list( $limit, $offset ) = wfCheckLimits( 20, 'searchlimit' );
 201
 202                 if ( $wgDisableTextSearch ) {
 203                         $wgOut->addHTML( wfMsg( 'searchdisabled' ) );
 204                         $wgOut->addHTML( wfMsg( 'googlesearch',
 205                                 htmlspecialchars( $this->rawText ),
 206                                 htmlspecialchars( $wgInputEncoding ) ) );
 207                         return;
 208                 }
 209
 210                 $titleMatches = $this->getMatches( $this->titleCond, $limit, $offset );
 211                 $textMatches = $this->getMatches( $this->textCond, $limit, $offset );
 212
 213                 $sk = $wgUser->getSkin();
 214
 215                 $num = count( $titleMatches ) + count( $textMatches );
 216                 if ( $num >= $limit ) {
 217                         $top = wfShowingResults( $offset, $limit );
 218                 } else {
 219                         $top = wfShowingResultsNum( $offset, $limit, $num );
 220                 }
 221                 $wgOut->addHTML( "<p>{$top}</p>\n" );
 222
 223                 # For powersearch
 224                 $a2l = '';
 225                 $akk = array_keys( $this->addToQuery );
 226                 foreach ( $akk AS $ak ) {
 227                         $a2l .= "&{$ak}={$this->addToQuery[$ak]}" ;
 228                 }
 229
 230                 $prevnext = wfViewPrevNext( $offset, $limit, '',
 231                   'search=' . wfUrlencode( $this->filteredText ) . $a2l );
 232                 $wgOut->addHTML( "<br />{$prevnext}\n" );
 233
 234                 $foundsome = $this->showMatches( $titleMatches, $offset, 'notitlematches', 'titlematches' )
 235                                   || $this->showMatches( $textMatches,  $offset, 'notextmatches',  'textmatches'  );
 236
 237                 if ( !$foundsome ) {
 238                         $wgOut->addWikiText( wfMsg( 'nonefound' ) );
 239                 }
 240                 $wgOut->addHTML( "<p>{$prevnext}</p>\n" );
 241                 $wgOut->addHTML( $powersearch );
 242         }
 243
 244         function legalSearchChars() {
 245                 $lc = "A-Za-z_'0-9\\x80-\\xFF\\-";
 246                 return $lc;
 247         }
 248
 249         function parseQuery() {
 250                 global $wgDBmysql4;
 251                 if( $wgDBmysql4 ) {
 252                         # Use cleaner boolean search if available
 253                         return $this->parseQuery4();
 254                 } else {
 255                         # Fall back to ugly hack with multiple search clauses
 256                         return $this->parseQuery3();
 257                 }
 258         }
 259
 260         function parseQuery3() {
 261                 global $wgDBminWordLen, $wgLang;
 262
 263                 # on non mysql4 database: get list of words we don't want to search for
 264                 require_once( 'FulltextStoplist.php' );
 265
 266                 $lc = SearchEngine::legalSearchChars() . '()';
 267                 $q = preg_replace( "/([()])/", " \\1 ", $this->filteredText );
 268                 $q = preg_replace( "/\\s+/", " ", $q );
 269                 $w = explode( ' ', trim( $q ) );
 270
 271                 $last = $cond = '';
 272                 foreach ( $w as $word ) {
 273                         $word = $wgLang->stripForSearch( $word );
 274                         if ( 'and' == $word || 'or' == $word || 'not' == $word
 275                           || '(' == $word || ')' == $word ) {
 276                                 $cond .= ' ' . strtoupper( $word );
 277                                 $last = '';
 278                         } else if ( strlen( $word ) < $wgDBminWordLen ) {
 279                                 continue;
 280                         } else if ( FulltextStoplist::inList( $word ) ) {
 281                                 continue;
 282                         } else {
 283                                 if ( '' != $last ) { $cond .= ' AND'; }
 284                                 $cond .= " (MATCH (##field##) AGAINST ('" .
 285                                   $this->db->strencode( $word ). "'))";
 286                                 $last = $word;
 287                                 array_push( $this->searchTerms, "\\b" . $word . "\\b" );
 288                         }
 289                 }
 290                 if ( 0 == count( $this->searchTerms ) ) {
 291                         return MW_SEARCH_BAD_QUERY;
 292                 }
 293
 294                 $this->titleCond = '(' . str_replace( '##field##',
 295                   'si_title', $cond ) . ' )';
 296
 297                 $this->textCond = '(' . str_replace( '##field##',
 298                   'si_text', $cond ) . ' AND (cur_is_redirect=0) )';
 299
 300                 return MW_SEARCH_OK;
 301         }
 302
 303         function parseQuery4() {
 304                 global $wgLang;
 305                 $lc = SearchEngine::legalSearchChars();
 306                 $searchon = '';
 307                 $this->searchTerms = array();
 308
 309                 # FIXME: This doesn't handle parenthetical expressions.
 310                 if( preg_match_all( '/([-+<>~]?)(([' . $lc . ']+)(\*?)|"[^"]*")/',
 311                           $this->filteredText, $m, PREG_SET_ORDER ) ) {
 312                         foreach( $m as $terms ) {
 313                                 if( $searchon !== '' ) $searchon .= ' ';
 314                                 if( $this->strictMatching && ($terms[1] == '') ) {
 315                                         $terms[1] = '+';
 316                                 }
 317                                 $searchon .= $terms[1] . $wgLang->stripForSearch( $terms[2] );
 318                                 if( !empty( $terms[3] ) ) {
 319                                         $regexp = preg_quote( $terms[3] );
 320                                         if( $terms[4] ) $regexp .= "[0-9A-Za-z_]+";
 321                                 } else {
 322                                         $regexp = preg_quote( str_replace( '"', '', $terms[2] ) );
 323                                 }
 324                                 $this->searchTerms[] = $regexp;
 325                         }
 326                         wfDebug( "Would search with '$searchon'\n" );
 327                         wfDebug( "Match with /\b" . implode( '\b|\b', $this->searchTerms ) . "\b/\n" );
 328                 } else {
 329                         wfDebug( "Can't understand search query '{$this->filteredText}'\n" );
 330                 }
 331
 332                 $searchon = $this->db->strencode( $searchon );
 333                 $this->titleCond = " MATCH(si_title) AGAINST('$searchon' IN BOOLEAN MODE)";
 334                 $this->textCond = " (MATCH(si_text) AGAINST('$searchon' IN BOOLEAN MODE) AND cur_is_redirect=0)";
 335                 return MW_SEARCH_OK;
 336         }
 337
 338         function &getMatches( $cond, $limit, $offset = 0 ) {
 339                 $searchindex = $this->db->tableName( 'searchindex' );
 340                 $cur = $this->db->tableName( 'cur' );
 341                 $searchnamespaces = $this->queryNamespaces();
 342                 $redircond = $this->searchRedirects();
 343
 344                 $sql = "SELECT cur_id,cur_namespace,cur_title," .
 345                   "cur_text FROM $cur,$searchindex " .
 346                   "WHERE cur_id=si_page AND {$cond} " .
 347                   "{$searchnamespaces} {$redircond} " .
 348                   $this->db->limitResult( $limit, $offset );
 349
 350                 $res = $this->db->query( $sql, 'SearchEngine::getMatches' );
 351                 $matches = array();
 352                 while ( $row = $this->db->fetchObject( $res ) ) {
 353                         $matches[] = $row;
 354                 }
 355                 $this->db->freeResult( $res );
 356
 357                 return $matches;
 358         }
 359
 360         function showMatches( &$matches, $offset, $msgEmpty, $msgFound ) {
 361                 global $wgOut;
 362                 if ( 0 == count( $matches ) ) {
 363                         $wgOut->addHTML( "<h2>" . wfMsg( $msgEmpty ) .
 364                           "</h2>\n" );
 365                         return false;
 366                 } else {
 367                         $off = $offset + 1;
 368                         $wgOut->addHTML( "<h2>" . wfMsg( $msgFound ) .
 369                           "</h2>\n<ol start='{$off}'>" );
 370
 371                         foreach( $matches as $row ) {
 372                                 $this->showHit( $row );
 373                         }
 374                         $wgOut->addHTML( "</ol>\n" );
 375                         return true;
 376                 }
 377         }
 378
 379         function showHit( $row ) {
 380                 global $wgUser, $wgOut, $wgLang;
 381
 382                 $t = Title::makeName( $row->cur_namespace, $row->cur_title );
 383                 if( is_null( $t ) ) {
 384                         $wgOut->addHTML( "<!-- Broken link in search result -->\n" );
 385                         return;
 386                 }
 387                 $sk = $wgUser->getSkin();
 388
 389                 $contextlines = $wgUser->getOption( 'contextlines' );
 390                 if ( '' == $contextlines ) { $contextlines = 5; }
 391                 $contextchars = $wgUser->getOption( 'contextchars' );
 392                 if ( '' == $contextchars ) { $contextchars = 50; }
 393
 394                 $link = $sk->makeKnownLink( $t, '' );
 395                 $size = wfMsg( 'nbytes', strlen( $row->cur_text ) );
 396                 $wgOut->addHTML( "<li>{$link} ({$size})" );
 397
 398                 $lines = explode( "\n", $row->cur_text );
 399                 $pat1 = "/(.*)(" . implode( "|", $this->searchTerms ) . ")(.*)/i";
 400                 $lineno = 0;
 401
 402                 foreach ( $lines as $line ) {
 403                         if ( 0 == $contextlines ) {
 404                                 break;
 405                         }
 406                         --$contextlines;
 407                         ++$lineno;
 408                         if ( ! preg_match( $pat1, $line, $m ) ) {
 409                                 continue;
 410                         }
 411
 412                         $pre = $wgLang->truncate( $m[1], -$contextchars, '...' );
 413
 414                         if ( count( $m ) < 3 ) {
 415                                 $post = '';
 416                         } else {
 417                                 $post = $wgLang->truncate( $m[3], $contextchars, '...' );
 418                         }
 419
 420                         $found = $m[2];
 421
 422                         $line = htmlspecialchars( $pre . $found . $post );
 423                         $pat2 = '/(' . implode( '|', $this->searchTerms ) . ")/i";
 424                         $line = preg_replace( $pat2,
 425                           "<span class='searchmatch'>\\1</span>", $line );
 426
 427                         $wgOut->addHTML( "<br /><small>{$lineno}: {$line}</small>\n" );
 428                 }
 429                 $wgOut->addHTML( "</li>\n" );
 430         }
 431
 432         function getNearMatch() {
 433                 # Exact match? No need to look further.
 434                 $title = Title::newFromText( $this->rawText );
 435                 if ( $title->getNamespace() == NS_SPECIAL || 0 != $title->getArticleID() ) {
 436                         return $title;
 437                 }
 438
 439                 # Now try all lower case (i.e. first letter capitalized)
 440                 #
 441                 $title = Title::newFromText( strtolower( $this->rawText ) );
 442                 if ( 0 != $title->getArticleID() ) {
 443                         return $title;
 444                 }
 445
 446                 # Now try capitalized string
 447                 #
 448                 $title = Title::newFromText( ucwords( strtolower( $this->rawText ) ) );
 449                 if ( 0 != $title->getArticleID() ) {
 450                         return $title;
 451                 }
 452
 453                 # Now try all upper case
 454                 #
 455                 $title = Title::newFromText( strtoupper( $this->rawText ) );
 456                 if ( 0 != $title->getArticleID() ) {
 457                         return $title;
 458                 }
 459
 460                 # Entering an IP address goes to the contributions page
 461                 if ( preg_match( '/^\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}$/', $this->rawText ) ) {
 462                         $title = Title::makeTitle( NS_SPECIAL, "Contributions/" . $this->rawText );
 463                         return $title;
 464                 }
 465
 466                 return NULL;
 467         }
 468
 469         function goResult() {
 470                 global $wgOut, $wgGoToEdit;
 471                 global $wgDisableTextSearch;
 472                 $fname = 'SearchEngine::goResult';
 473
 474                 # Try to go to page as entered.
 475                 #
 476                 $t = Title::newFromText( $this->rawText );
 477
 478                 # If the string cannot be used to create a title
 479                 if( is_null( $t ) ){
 480                         $this->showResults();
 481                         return;
 482                 }
 483
 484                 # If there's an exact or very near match, jump right there.
 485                 $t = $this->getNearMatch();
 486                 if( !is_null( $t ) ) {
 487                         $wgOut->redirect( $t->getFullURL() );
 488                         return;
 489                 }
 490
 491                 # No match, generate an edit URL
 492                 $t = Title::newFromText( $this->rawText );
 493
 494                 # If the feature is enabled, go straight to the edit page
 495                 if ( $wgGoToEdit ) {
 496                         $wgOut->redirect( $t->getFullURL( 'action=edit' ) );
 497                         return;
 498                 }
 499
 500                 if( $t ) {
 501                         $editurl = $t->escapeLocalURL( 'action=edit' );
 502                 } else {
 503                         $editurl = ''; # ??
 504                 }
 505                 $wgOut->addHTML( '<p>' . wfMsg('nogomatch', $editurl ) . "</p>\n" );
 506
 507                 # Try a fuzzy title search
 508                 $anyhit = false;
 509                 global $wgDisableFuzzySearch;
 510                 if(! $wgDisableFuzzySearch ){
 511                         foreach( array(NS_MAIN, NS_PROJECT, NS_USER, NS_IMAGE, NS_MEDIAWIKI) as $namespace){
 512                                 $anyhit |= SearchEngine::doFuzzyTitleSearch( $this->rawText, $namespace );
 513                         }
 514                 }
 515
 516                 if( ! $anyhit ){
 517                         return $this->showResults();
 518                 }
 519         }
 520
 521         /**
 522          * @static
 523          */
 524         function doFuzzyTitleSearch( $search, $namespace ){
 525                 global $wgLang, $wgOut;
 526
 527                 $this->setupPage();
 528
 529                 $sstr = ucfirst($search);
 530                 $sstr = str_replace(' ', '_', $sstr);
 531                 $fuzzymatches = SearchEngine::fuzzyTitles( $sstr, $namespace );
 532                 $fuzzymatches = array_slice($fuzzymatches, 0, 10);
 533                 $slen = strlen( $search );
 534                 $wikitext = '';
 535                 foreach($fuzzymatches as $res){
 536                         $t = str_replace('_', ' ', $res[1]);
 537                         $tfull = $wgLang->getNsText( $namespace ) . ":$t|$t";
 538                         if( $namespace == NS_MAIN )
 539                                 $tfull = "$t";
 540                         $distance = $res[0];
 541                         $closeness = (strlen( $search ) - $distance) / strlen( $search );
 542                         $percent = intval( $closeness * 100 ) . '%';
 543                         $stars = str_repeat('*', ceil(5 * $closeness) );
 544                         $wikitext .= "* [[$tfull]] $percent ($stars)\n";
 545                 }
 546                 if( $wikitext ){
 547                         if( $namespace != NS_MAIN )
 548                                 $wikitext = '=== ' . $wgLang->getNsText( $namespace ) . " ===\n" . $wikitext;
 549                         $wgOut->addWikiText( $wikitext );
 550                         return true;
 551                 }
 552                 return false;
 553         }
 554
 555         /**
 556          * @static
 557          */
 558         function fuzzyTitles( $sstr, $namespace = NS_MAIN ){
 559                 $span = 0.10; // weed on title length before doing levenshtein.
 560                 $tolerance = 0.35; // allowed percentage of erronous characters
 561                 $slen = strlen($sstr);
 562                 $tolerance_count = ceil($tolerance * $slen);
 563                 $spanabs = ceil($slen * (1 + $span)) - $slen;
 564                 # print "Word: $sstr, len = $slen, range = [$min, $max], tolerance_count = $tolerance_count<BR>\n";
 565                 $result = array();
 566                 $cnt = 0;
 567                 for( $i=0; $i <= $spanabs; $i++ ){
 568                         $titles = SearchEngine::getTitlesByLength( $slen + $i, $namespace );
 569                         if( $i != 0) {
 570                                 $titles = array_merge($titles, SearchEngine::getTitlesByLength( $slen - $i, $namespace ) );
 571                         }
 572                         foreach($titles as $t){
 573                                 $d = levenshtein($sstr, $t);
 574                                 if($d < $tolerance_count)
 575                                         $result[] = array($d, $t);
 576                                 $cnt++;
 577                         }
 578                 }
 579                 usort($result, 'SearchEngine_pcmp');
 580                 return $result;
 581         }
 582
 583         /**
 584          * static
 585          */
 586         function getTitlesByLength($aLength, $aNamespace = 0){
 587                 global $wgMemc, $wgDBname;
 588                 $fname = 'SearchEngin::getTitlesByLength';
 589
 590                 // to avoid multiple costly SELECTs in case of no memcached
 591                 if( $this->allTitles ){
 592                         if( isset( $this->allTitles[$aLength][$aNamespace] ) ){
 593                                 return $this->allTitles[$aLength][$aNamespace];
 594                         } else {
 595                                 return array();
 596                         }
 597                 }
 598
 599                 $mkey = "$wgDBname:titlesbylength:$aLength:$aNamespace";
 600                 $mkeyts = "$wgDBname:titlesbylength:createtime";
 601                 $ts = $wgMemc->get( $mkeyts );
 602                 $result = $wgMemc->get( $mkey );
 603
 604                 if( time() - $ts < 3600 ){
 605                         // note: in case of insufficient memcached space, we return
 606                         // an empty list instead of starting to hit the DB.
 607                         return is_array( $result ) ? $result : array();
 608                 }
 609
 610                 $wgMemc->set( $mkeyts, time() );
 611
 612                 $res = $this->db->select( 'cur', array( 'cur_title', 'cur_namespace' ), false, $fname );
 613                 $titles = array(); // length, ns, [titles]
 614                 while( $obj = $this->db->fetchObject( $res ) ){
 615                         $title = $obj->cur_title;
 616                         $ns = $obj->cur_namespace;
 617                         $len = strlen( $title );
 618                         $titles[$len][$ns][] = $title;
 619                 }
 620                 foreach($titles as $length => $length_arr){
 621                         foreach($length_arr as $ns => $title_arr){
 622                                 $mkey = "$wgDBname:titlesbylength:$length:$ns";
 623                                 $wgMemc->set( $mkey, $title_arr, 3600 * 24 );
 624                         }
 625                 }
 626                 $this->allTitles = $titles;
 627                 if( isset( $titles[$aLength][$aNamespace] ) )
 628                         return $titles[$aLength][$aNamespace];
 629                 else
 630                         return array();
 631         }
 632 }
 633
 634 /**
 635  * @access private
 636  * @static
 637  */
 638 function SearchEngine_pcmp($a, $b){ return $a[0] - $b[0]; }
 639
 640 ?>