includes/SearchEngine.php

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