Don't look for pipes in the root node.
[lhc/web/wiklou.git] / includes / QueryPage.php
index 75dc112..f656949 100644 (file)
@@ -1,59 +1,68 @@
 <?php
 /**
  * Contain a class for special pages
+ * @file
+ * @ingroup SpecialPages
  */
 
 /**
- * List of query page classes and their associated special pages, 
+ * List of query page classes and their associated special pages,
  * for periodic updates.
  *
- * DO NOT CHANGE THIS LIST without testing that 
+ * DO NOT CHANGE THIS LIST without testing that
  * maintenance/updateSpecialPages.php still works.
  */
 global $wgQueryPages; // not redundant
 $wgQueryPages = array(
 //         QueryPage subclass           Special page name         Limit (false for none, none for the default)
-//----------------------------------------------------------------------------
+// ----------------------------------------------------------------------------
        array( 'AncientPagesPage',              'Ancientpages'                  ),
        array( 'BrokenRedirectsPage',           'BrokenRedirects'               ),
        array( 'DeadendPagesPage',              'Deadendpages'                  ),
        array( 'DisambiguationsPage',           'Disambiguations'               ),
        array( 'DoubleRedirectsPage',           'DoubleRedirects'               ),
-       array( 'ListredirectsPage',             'Listredirects'                                 ),
+       array( 'FileDuplicateSearchPage',       'FileDuplicateSearch'           ),
+       array( 'LinkSearchPage',                'LinkSearch'                    ),
+       array( 'ListredirectsPage',             'Listredirects'                 ),
        array( 'LonelyPagesPage',               'Lonelypages'                   ),
        array( 'LongPagesPage',                 'Longpages'                     ),
+       array( 'MIMEsearchPage',                'MIMEsearch'                    ),
        array( 'MostcategoriesPage',            'Mostcategories'                ),
        array( 'MostimagesPage',                'Mostimages'                    ),
        array( 'MostlinkedCategoriesPage',      'Mostlinkedcategories'          ),
+       array( 'MostlinkedtemplatesPage',       'Mostlinkedtemplates'           ),
        array( 'MostlinkedPage',                'Mostlinked'                    ),
        array( 'MostrevisionsPage',             'Mostrevisions'                 ),
-       array( 'NewPagesPage',                  'Newpages'                      ),
+       array( 'FewestrevisionsPage',           'Fewestrevisions'               ),
        array( 'ShortPagesPage',                'Shortpages'                    ),
        array( 'UncategorizedCategoriesPage',   'Uncategorizedcategories'       ),
        array( 'UncategorizedPagesPage',        'Uncategorizedpages'            ),
-       array( 'UncategorizedImagesPage',       'Uncategorizedimages'                   ),
+       array( 'UncategorizedImagesPage',       'Uncategorizedimages'           ),
+       array( 'UncategorizedTemplatesPage',    'Uncategorizedtemplates'        ),
        array( 'UnusedCategoriesPage',          'Unusedcategories'              ),
        array( 'UnusedimagesPage',              'Unusedimages'                  ),
        array( 'WantedCategoriesPage',          'Wantedcategories'              ),
+       array( 'WantedFilesPage',               'Wantedfiles'                   ),
        array( 'WantedPagesPage',               'Wantedpages'                   ),
+       array( 'WantedTemplatesPage',           'Wantedtemplates'               ),
        array( 'UnwatchedPagesPage',            'Unwatchedpages'                ),
-       array( 'UnusedtemplatesPage',           'Unusedtemplates'                               ),
-       array( 'WithoutInterwikiPage',                  'Withoutinterwiki'                              ),
+       array( 'UnusedtemplatesPage',           'Unusedtemplates'               ),
+       array( 'WithoutInterwikiPage',          'Withoutinterwiki'              ),
 );
 wfRunHooks( 'wgQueryPages', array( &$wgQueryPages ) );
 
 global $wgDisableCounters;
 if ( !$wgDisableCounters )
-       $wgQueryPages[] = array( 'PopularPagesPage',            'Popularpages'          );
+       $wgQueryPages[] = array( 'PopularPagesPage', 'Popularpages' );
 
 
 /**
  * This is a class for doing query pages; since they're almost all the same,
  * we factor out some of the functionality into a superclass, and let
  * subclasses derive from it.
- *
+ * @ingroup SpecialPage
  */
-class QueryPage {
+abstract class QueryPage extends SpecialPage {
        /**
         * Whether or not we want plain listoutput rather than an ordered list
         *
@@ -70,78 +79,130 @@ class QueryPage {
        var $limit = 0;
 
        /**
-        * A mutator for $this->listoutput;
-        *
-        * @param bool $bool
+        * The number of rows returned by the query. Reading this variable
+        * only makes sense in functions that are run after the query has been
+        * done, such as preprocessResults() and formatRow().
         */
-       function setListoutput( $bool ) {
-               $this->listoutput = $bool;
-       }
+       protected $numRows;
+
+       protected $cachedTimestamp = null;
 
        /**
-        * Subclasses return their name here. Make sure the name is also
-        * specified in SpecialPage.php and in Language.php as a language message
-        * param.
+        * Wheter to show prev/next links
         */
-       function getName() {
-               return '';
-       }
+       protected $shownavigation = true;
 
        /**
-        * Return title object representing this page
+        * A mutator for $this->listoutput;
         *
-        * @return Title
+        * @param $bool Boolean
         */
-       function getTitle() {
-               return SpecialPage::getTitleFor( $this->getName() );
+       function setListoutput( $bool ) {
+               $this->listoutput = $bool;
        }
 
        /**
-        * Subclasses return an SQL query here.
+        * Subclasses return an SQL query here, formatted as an array with the
+        * following keys:
+        *    tables => Table(s) for passing to Database::select()
+        *    fields => Field(s) for passing to Database::select(), may be *
+        *    conds => WHERE conditions
+        *    options => options
+        *    join_conds => JOIN conditions
         *
-        * Note that the query itself should return the following four columns:
-        * 'type' (your special page's name), 'namespace', 'title', and 'value'
-        * *in that order*. 'value' is used for sorting.
+        * Note that the query itself should return the following three columns:
+        * 'namespace', 'title', and 'value'. 'value' is used for sorting.
         *
         * These may be stored in the querycache table for expensive queries,
         * and that cached data will be returned sometimes, so the presence of
         * extra fields can't be relied upon. The cached 'value' column will be
-        * an integer; non-numeric values are useful only for sorting the initial
-        * query.
+        * an integer; non-numeric values are useful only for sorting the
+        * initial query (except if they're timestamps, see usesTimestamps()).
+        *
+        * Don't include an ORDER or LIMIT clause, they will be added.
         *
-        * Don't include an ORDER or LIMIT clause, this will be added.
+        * If this function is not overridden or returns something other than
+        * an array, getSQL() will be used instead. This is for backwards
+        * compatibility only and is strongly deprecated.
+        * @return array
+        * @since 1.18
+        */
+       function getQueryInfo() {
+               return null;
+       }
+       
+       /**
+        * For back-compat, subclasses may return a raw SQL query here, as a string.
+        * This is stronly deprecated; getQueryInfo() should be overridden instead.
+        * @return string
         */
        function getSQL() {
-               return "SELECT 'sample' as type, 0 as namespace, 'Sample result' as title, 42 as value";
+               /* Implement getQueryInfo() instead */
+               throw new MWException( "Bug in a QueryPage: doesn't implement getQueryInfo() nor getQuery() properly" );
+       }
+
+       /**
+        * Subclasses return an array of fields to order by here. Don't append
+        * DESC to the field names, that'll be done automatically if
+        * sortDescending() returns true.
+        * @return array
+        * @since 1.18
+        */
+       function getOrderFields() {
+               return array( 'value' );
+       }
+
+       /**
+        * Does this query return timestamps rather than integers in its
+        * 'value' field? If true, this class will convert 'value' to a
+        * UNIX timestamp for caching.
+        * NOTE: formatRow() may get timestamps in TS_MW (mysql), TS_DB (pgsql)
+        *       or TS_UNIX (querycache) format, so be sure to always run them
+        *       through wfTimestamp()
+        * @return bool
+        * @since 1.18
+        */
+       function usesTimestamps() {
+               return false;
        }
 
        /**
         * Override to sort by increasing values
+        *
+        * @return Boolean
         */
        function sortDescending() {
                return true;
        }
 
-       function getOrder() {
-               return ' ORDER BY value ' .
-                       ($this->sortDescending() ? 'DESC' : '');
-       }
-
        /**
         * Is this query expensive (for some definition of expensive)? Then we
         * don't let it run in miser mode. $wgDisableQueryPages causes all query
         * pages to be declared expensive. Some query pages are always expensive.
+        *
+        * @return Boolean
         */
-       function isExpensive( ) {
+       function isExpensive() {
                global $wgDisableQueryPages;
                return $wgDisableQueryPages;
        }
 
        /**
-        * Whether or not the output of the page in question is retrived from
+        * Is the output of this query cacheable? Non-cacheable expensive pages
+        * will be disabled in miser mode and will not have their results written
+        * to the querycache table.
+        * @return Boolean
+        * @since 1.18
+        */
+       public function isCacheable() {
+               return true;
+       }
+
+       /**
+        * Whether or not the output of the page in question is retrieved from
         * the database cache.
         *
-        * @return bool
+        * @return Boolean
         */
        function isCached() {
                global $wgMiserMode;
@@ -151,6 +212,8 @@ class QueryPage {
 
        /**
         * Sometime we dont want to build rss / atom feeds.
+        *
+        * @return Boolean
         */
        function isSyndicated() {
                return true;
@@ -160,16 +223,22 @@ class QueryPage {
         * Formats the results of the query for display. The skin is the current
         * skin; you can use it for making links. The result is a single row of
         * result data. You should be able to grab SQL results off of it.
-        * If the function return "false", the line output will be skipped.
+        * If the function returns false, the line output will be skipped.
+        * @param $skin Skin
+        * @param $result object Result row
+        * @return mixed String or false to skip
+        *
+        * @param $skin Skin object
+        * @param $result Object: database row
         */
-       function formatResult( $skin, $result ) {
-               return '';
-       }
+       abstract function formatResult( $skin, $result );
 
        /**
         * The content returned by this function will be output before any result
+        *
+        * @return String
         */
-       function getPageHeader( ) {
+       function getPageHeader() {
                return '';
        }
 
@@ -177,7 +246,8 @@ class QueryPage {
         * If using extra form wheely-dealies, return a set of parameters here
         * as an associative array. They will be encoded and added to the paging
         * links (prev/next/lengths).
-        * @return array
+        *
+        * @return Array
         */
        function linkParameters() {
                return array();
@@ -186,26 +256,32 @@ class QueryPage {
        /**
         * Some special pages (for example SpecialListusers) might not return the
         * current object formatted, but return the previous one instead.
-        * Setting this to return true, will call one more time wfFormatResult to
-        * be sure that the very last result is formatted and shown.
+        * Setting this to return true will ensure formatResult() is called
+        * one more time to make sure that the very last result is formatted
+        * as well.
         */
-       function tryLastResult( ) {
+       function tryLastResult() {
                return false;
        }
 
        /**
         * Clear the cache and save new results
+        *
+        * @param $limit Integer: limit for SQL statement
+        * @param $ignoreErrors Boolean: whether to ignore database errors
         */
        function recache( $limit, $ignoreErrors = true ) {
-               $fname = get_class($this) . '::recache';
+               if ( !$this->isCacheable() ) {
+                       return 0;
+               }
+               
+               $fname = get_class( $this ) . '::recache';
                $dbw = wfGetDB( DB_MASTER );
-               $dbr = wfGetDB( DB_SLAVE, array( $this->getName(), 'QueryPage::recache', 'vslow' ) );
+               $dbr = wfGetDB( DB_SLAVE, array( $this->getName(), __METHOD__, 'vslow' ) );
                if ( !$dbw || !$dbr ) {
                        return false;
                }
 
-               $querycache = $dbr->tableName( 'querycache' );
-
                if ( $ignoreErrors ) {
                        $ignoreW = $dbw->ignoreErrors( true );
                        $ignoreR = $dbr->ignoreErrors( true );
@@ -214,46 +290,37 @@ class QueryPage {
                # Clear out any old cached data
                $dbw->delete( 'querycache', array( 'qc_type' => $this->getName() ), $fname );
                # Do query
-               $sql = $this->getSQL() . $this->getOrder();
-               if ($limit !== false)
-                       $sql = $dbr->limitResult($sql, $limit, 0);
-               $res = $dbr->query($sql, $fname);
+               $res = $this->reallyDoQuery( $limit, false );
                $num = false;
                if ( $res ) {
                        $num = $dbr->numRows( $res );
                        # Fetch results
-                       $insertSql = "INSERT INTO $querycache (qc_type,qc_namespace,qc_title,qc_value) VALUES ";
-                       $first = true;
+                       $vals = array();
                        while ( $res && $row = $dbr->fetchObject( $res ) ) {
-                               if ( $first ) {
-                                       $first = false;
-                               } else {
-                                       $insertSql .= ',';
-                               }
                                if ( isset( $row->value ) ) {
-                                       $value = $row->value;
+                                       if ( $this->usesTimestamps() ) {
+                                               $value = wfTimestamp( TS_UNIX,
+                                                       $row->value );
+                                       } else {
+                                               $value = intval( $row->value ); // @bug 14414
+                                       }
                                } else {
-                                       $value = '';
+                                       $value = 0;
                                }
 
-                               $insertSql .= '(' .
-                                       $dbw->addQuotes( $row->type ) . ',' .
-                                       $dbw->addQuotes( $row->namespace ) . ',' .
-                                       $dbw->addQuotes( $row->title ) . ',' .
-                                       $dbw->addQuotes( $value ) . ')';
+                               $vals[] = array( 'qc_type' => $this->getName(),
+                                               'qc_namespace' => $row->namespace,
+                                               'qc_title' => $row->title,
+                                               'qc_value' => $value );
                        }
 
                        # Save results into the querycache table on the master
-                       if ( !$first ) {
-                               if ( !$dbw->query( $insertSql, $fname ) ) {
+                       if ( count( $vals ) ) {
+                               if ( !$dbw->insert( 'querycache', $vals, __METHOD__ ) ) {
                                        // Set result to false to indicate error
-                                       $dbr->freeResult( $res );
-                                       $res = false;
+                                       $num = false;
                                }
                        }
-                       if ( $res ) {
-                               $dbr->freeResult( $res );
-                       }
                        if ( $ignoreErrors ) {
                                $dbw->ignoreErrors( $ignoreW );
                                $dbr->ignoreErrors( $ignoreR );
@@ -267,89 +334,183 @@ class QueryPage {
                return $num;
        }
 
+       /**
+        * Run the query and return the result
+        * @param $limit mixed Numerical limit or false for no limit
+        * @param $offset mixed Numerical offset or false for no offset
+        * @return ResultWrapper
+        * @since 1.18
+        */
+       function reallyDoQuery( $limit, $offset = false ) {
+               $fname = get_class( $this ) . "::reallyDoQuery";
+               $dbr = wfGetDB( DB_SLAVE );
+               $query = $this->getQueryInfo();
+               $order = $this->getOrderFields();
+               if ( $this->sortDescending() ) {
+                       foreach ( $order as &$field ) {
+                               $field .= ' DESC';
+                       }
+               }
+               if ( is_array( $query ) ) {
+                       $tables = isset( $query['tables'] ) ? (array)$query['tables'] : array();
+                       $fields = isset( $query['fields'] ) ? (array)$query['fields'] : array();
+                       $conds = isset( $query['conds'] ) ? (array)$query['conds'] : array();
+                       $options = isset( $query['options'] ) ? (array)$query['options'] : array();
+                       $join_conds = isset( $query['join_conds'] ) ? (array)$query['join_conds'] : array();
+                       if ( count( $order ) ) {
+                               $options['ORDER BY'] = implode( ', ', $order );
+                       }
+                       if ( $limit !== false ) {
+                               $options['LIMIT'] = intval( $limit );
+                       }
+                       if ( $offset !== false ) {
+                               $options['OFFSET'] = intval( $offset );
+                       }
+
+                       $res = $dbr->select( $tables, $fields, $conds, $fname,
+                                       $options, $join_conds
+                       );
+               } else {
+                       // Old-fashioned raw SQL style, deprecated
+                       $sql = $this->getSQL();
+                       $sql .= ' ORDER BY ' . implode( ', ', $order );
+                       $sql = $dbr->limitResult( $sql, $limit, $offset );
+                       $res = $dbr->query( $sql, $fname );
+               }
+               return $dbr->resultObject( $res );
+       }
+
+       /**
+        * Parameters and order changed in 1.18
+        */
+       function doQuery( $limit, $offset = false ) {
+               if ( $this->isCached() && $this->isCacheable() ) {
+                       return $this->fetchFromCache( $limit, $offset );
+               } else {
+                       return $this->reallyDoQuery( $limit, $offset );
+               }
+       }
+
+       /**
+        * Fetch the query results from the query cache
+        * @param $limit mixed Numerical limit or false for no limit
+        * @param $offset mixed Numerical offset or false for no offset
+        * @return ResultWrapper
+        * @since 1.18
+        */
+       function fetchFromCache( $limit, $offset = false ) {
+               $dbr = wfGetDB( DB_SLAVE );
+               $options = array ();
+               if ( $limit !== false ) {
+                       $options['LIMIT'] = intval( $limit );
+               }
+               if ( $offset !== false ) {
+                       $options['OFFSET'] = intval( $offset );
+               }
+               $res = $dbr->select( 'querycache', array( 'qc_type',
+                               'qc_namespace AS namespace',
+                               'qc_title AS title',
+                               'qc_value AS value' ),
+                               array( 'qc_type' => $this->getName() ),
+                               __METHOD__, $options
+               );
+               return $dbr->resultObject( $res );
+       }
+       
+       public function getCachedTimestamp() {
+               if ( !is_null( $this->cachedTimestamp ) ) {
+                       $dbr = wfGetDB( DB_SLAVE );
+                       $fname = get_class( $this ) . '::getCachedTimestamp';
+                       $this->cachedTimestamp = $dbr->selectField( 'querycache_info', 'qci_timestamp',
+                               array( 'qci_type' => $this->getName() ), $fname );
+               }
+               return $this->cachedTimestamp;
+       }
+
        /**
         * This is the actual workhorse. It does everything needed to make a
         * real, honest-to-gosh query page.
-        *
-        * @param $offset database query offset
-        * @param $limit database query limit
-        * @param $shownavigation show navigation like "next 200"?
         */
-       function doQuery( $offset, $limit, $shownavigation=true ) {
-               global $wgUser, $wgOut, $wgLang, $wgContLang;
+       function execute( $par ) {
+               global $wgUser, $wgOut, $wgLang;
 
-               $this->offset = $offset;
-               $this->limit = $limit;
+               if ( !$this->userCanExecute( $wgUser ) ) {
+                       $this->displayRestrictionError();
+                       return;
+               }
 
-               $sname = $this->getName();
-               $fname = get_class($this) . '::doQuery';
+               if ( $this->limit == 0 && $this->offset == 0 )
+                       list( $this->limit, $this->offset ) = wfCheckLimits();
                $dbr = wfGetDB( DB_SLAVE );
 
+               $this->setHeaders();
                $wgOut->setSyndicated( $this->isSyndicated() );
 
+               if ( $this->isCached() && !$this->isCacheable() ) {
+                       $wgOut->setSyndicated( false );
+                       $wgOut->addWikiMsg( 'querypage-disabled' );
+                       return 0;
+               }
+
+               // TODO: Use doQuery()
+               // $res = null;
                if ( !$this->isCached() ) {
-                       $sql = $this->getSQL();
+                       $res = $this->reallyDoQuery( $this->limit, $this->offset );
                } else {
                        # Get the cached result
-                       $querycache = $dbr->tableName( 'querycache' );
-                       $type = $dbr->strencode( $sname );
-                       $sql =
-                               "SELECT qc_type as type, qc_namespace as namespace,qc_title as title, qc_value as value
-                                FROM $querycache WHERE qc_type='$type'";
-
-                       if( !$this->listoutput ) {
+                       $res = $this->fetchFromCache( $this->limit, $this->offset );
+                       if ( !$this->listoutput ) {
 
                                # Fetch the timestamp of this update
-                               $tRes = $dbr->select( 'querycache_info', array( 'qci_timestamp' ), array( 'qci_type' => $type ), $fname );
-                               $tRow = $dbr->fetchObject( $tRes );
-                               
-                               if( $tRow ) {
-                                       $updated = $wgLang->timeAndDate( $tRow->qci_timestamp, true, true );
-                                       $cacheNotice = wfMsg( 'perfcachedts', $updated );
-                                       $wgOut->addMeta( 'Data-Cache-Time', $tRow->qci_timestamp );
-                                       $wgOut->addInlineScript( "var dataCacheTime = '{$tRow->qci_timestamp}';" );
+                               $ts = $this->getCachedTimestamp();
+
+                               if ( $ts ) {
+                                       $updated = $wgLang->timeanddate( $ts, true, true );
+                                       $updateddate = $wgLang->date( $ts, true, true );
+                                       $updatedtime = $wgLang->time( $ts, true, true );
+                                       $wgOut->addMeta( 'Data-Cache-Time', $ts );
+                                       $wgOut->addInlineScript( "var dataCacheTime = '$ts';" );
+                                       $wgOut->addWikiMsg( 'perfcachedts', $updated, $updateddate, $updatedtime );
                                } else {
-                                       $cacheNotice = wfMsg( 'perfcached' );
+                                       $wgOut->addWikiMsg( 'perfcached' );
                                }
-       
-                               $wgOut->addWikiText( $cacheNotice );
-                               
+
                                # If updates on this page have been disabled, let the user know
                                # that the data set won't be refreshed for now
                                global $wgDisableQueryPageUpdate;
-                               if( is_array( $wgDisableQueryPageUpdate ) && in_array( $this->getName(), $wgDisableQueryPageUpdate ) ) {
-                                       $wgOut->addWikiText( wfMsg( 'querypage-no-updates' ) );
+                               if ( is_array( $wgDisableQueryPageUpdate ) && in_array( $this->getName(), $wgDisableQueryPageUpdate ) ) {
+                                       $wgOut->addWikiMsg( 'querypage-no-updates' );
                                }
-                               
+
                        }
 
                }
 
-               $sql .= $this->getOrder();
-               $sql = $dbr->limitResult($sql, $limit, $offset);
-               $res = $dbr->query( $sql );
-               $num = $dbr->numRows($res);
+               $this->numRows = $dbr->numRows( $res );
 
                $this->preprocessResults( $dbr, $res );
-               $sk = $wgUser->getSkin();
-               
+
+               $wgOut->addHTML( Xml::openElement( 'div', array( 'class' => 'mw-spcontent' ) ) );
+
                # Top header and navigation
-               if( $shownavigation ) {
-                       $wgOut->addHtml( $this->getPageHeader() );
-                       if( $num > 0 ) {
-                               $wgOut->addHtml( '<p>' . wfShowingResults( $offset, $num ) . '</p>' );
+               if ( $this->shownavigation ) {
+                       $wgOut->addHTML( $this->getPageHeader() );
+                       if ( $this->numRows > 0 ) {
+                               $wgOut->addHTML( '<p>' . wfShowingResults( $this->offset, $this->numRows ) . '</p>' );
                                # Disable the "next" link when we reach the end
-                               $paging = wfViewPrevNext( $offset, $limit, $wgContLang->specialPage( $sname ),
-                                       wfArrayToCGI( $this->linkParameters() ), ( $num < $limit ) );
-                               $wgOut->addHtml( '<p>' . $paging . '</p>' );
+                               $paging = wfViewPrevNext( $this->offset, $this->limit,
+                                       $this->getTitle( $par ),
+                                       wfArrayToCGI( $this->linkParameters() ), ( $this->numRows < $this->limit ) );
+                               $wgOut->addHTML( '<p>' . $paging . '</p>' );
                        } else {
                                # No results to show, so don't bother with "showing X of Y" etc.
                                # -- just let the user know and give up now
-                               $wgOut->addHtml( '<p>' . wfMsgHtml( 'specialpage-empty' ) . '</p>' );
+                               $wgOut->addHTML( '<p>' . wfMsgHtml( 'specialpage-empty' ) . '</p>' );
+                               $wgOut->addHTML( Xml::closeElement( 'div' ) );
                                return;
                        }
                }
-               
+
                # The actual results; specialist subclasses will want to handle this
                # with more than a straight list, so we hand them the info, plus
                # an OutputPage, and let them get on with it
@@ -357,96 +518,108 @@ class QueryPage {
                        $wgUser->getSkin(),
                        $dbr, # Should use a ResultWrapper for this
                        $res,
-                       $dbr->numRows( $res ),
-                       $offset );
+                       $this->numRows,
+                       $this->offset );
 
                # Repeat the paging links at the bottom
-               if( $shownavigation ) {
-                       $wgOut->addHtml( '<p>' . $paging . '</p>' );
+               if ( $this->shownavigation ) {
+                       $wgOut->addHTML( '<p>' . $paging . '</p>' );
                }
-               
-               return $num;
+
+               $wgOut->addHTML( Xml::closeElement( 'div' ) );
+
+               return $this->numRows;
        }
-       
+
        /**
         * Format and output report results using the given information plus
         * OutputPage
         *
-        * @param OutputPage $out OutputPage to print to
-        * @param Skin $skin User skin to use
-        * @param Database $dbr Database (read) connection to use
-        * @param int $res Result pointer
-        * @param int $num Number of available result rows
-        * @param int $offset Paging offset
+        * @param $out OutputPage to print to
+        * @param $skin Skin: user skin to use
+        * @param $dbr Database (read) connection to use
+        * @param $res Integer: result pointer
+        * @param $num Integer: number of available result rows
+        * @param $offset Integer: paging offset
         */
        protected function outputResults( $out, $skin, $dbr, $res, $num, $offset ) {
                global $wgContLang;
-       
-               if( $num > 0 ) {
+
+               if ( $num > 0 ) {
                        $html = array();
-                       if( !$this->listoutput )
+                       if ( !$this->listoutput )
                                $html[] = $this->openList( $offset );
-                       
+
                        # $res might contain the whole 1,000 rows, so we read up to
                        # $num [should update this to use a Pager]
-                       for( $i = 0; $i < $num && $row = $dbr->fetchObject( $res ); $i++ ) {
+                       for ( $i = 0; $i < $num && $row = $dbr->fetchObject( $res ); $i++ ) {
                                $line = $this->formatResult( $skin, $row );
-                               if( $line ) {
-                                       $attr = ( isset( $obj->usepatrol ) && $obj->usepatrol && $obj->patrolled == 0 )
+                               if ( $line ) {
+                                       $attr = ( isset( $row->usepatrol ) && $row->usepatrol && $row->patrolled == 0 )
                                                ? ' class="not-patrolled"'
                                                : '';
                                        $html[] = $this->listoutput
-                                               ? $format
+                                               ? $line
                                                : "<li{$attr}>{$line}</li>\n";
                                }
                        }
-                       
+
                        # Flush the final result
-                       if( $this->tryLastResult() ) {
+                       if ( $this->tryLastResult() ) {
                                $row = null;
                                $line = $this->formatResult( $skin, $row );
-                               if( $line ) {
-                                       $attr = ( isset( $obj->usepatrol ) && $obj->usepatrol && $obj->patrolled == 0 )
+                               if ( $line ) {
+                                       $attr = ( isset( $row->usepatrol ) && $row->usepatrol && $row->patrolled == 0 )
                                                ? ' class="not-patrolled"'
                                                : '';
                                        $html[] = $this->listoutput
-                                               ? $format
+                                               ? $line
                                                : "<li{$attr}>{$line}</li>\n";
                                }
                        }
-                       
-                       if( !$this->listoutput )
+
+                       if ( !$this->listoutput )
                                $html[] = $this->closeList();
-                       
+
                        $html = $this->listoutput
                                ? $wgContLang->listToText( $html )
                                : implode( '', $html );
-                       
-                       $out->addHtml( $html );
+
+                       $out->addHTML( $html );
                }
        }
-       
+
        function openList( $offset ) {
-               return "<ol start='" . ( $offset + 1 ) . "' class='special'>";
+               return "\n<ol start='" . ( $offset + 1 ) . "' class='special'>\n";
        }
-       
+
        function closeList() {
-               return '</ol>';
+               return "</ol>\n";
        }
 
        /**
         * Do any necessary preprocessing of the result object.
-        * You should pass this by reference: &$db , &$res  [although probably no longer necessary in PHP5]
         */
-       function preprocessResults( &$db, &$res ) {}
+       function preprocessResults( $db, $res ) {}
 
        /**
         * Similar to above, but packaging in a syndicated feed instead of a web page
         */
        function doFeed( $class = '', $limit = 50 ) {
-               global $wgFeedClasses;
+               global $wgFeed, $wgFeedClasses;
+
+               if ( !$wgFeed ) {
+                       global $wgOut;
+                       $wgOut->addWikiMsg( 'feed-unavailable' );
+                       return;
+               }
 
-               if( isset($wgFeedClasses[$class]) ) {
+               global $wgFeedLimit;
+               if ( $limit > $wgFeedLimit ) {
+                       $limit = $wgFeedLimit;
+               }
+
+               if ( isset( $wgFeedClasses[$class] ) ) {
                        $feed = new $wgFeedClasses[$class](
                                $this->feedTitle(),
                                $this->feedDesc(),
@@ -454,14 +627,13 @@ class QueryPage {
                        $feed->outHeader();
 
                        $dbr = wfGetDB( DB_SLAVE );
-                       $sql = $this->getSQL() . $this->getOrder();
-                       $sql = $dbr->limitResult( $sql, $limit, 0 );
-                       $res = $dbr->query( $sql, 'QueryPage::doFeed' );
-                       while( $obj = $dbr->fetchObject( $res ) ) {
+                       $res = $this->reallyDoQuery( $limit, 0 );
+                       foreach ( $res as $obj ) {
                                $item = $this->feedResult( $obj );
-                               if( $item ) $feed->outItem( $item );
+                               if ( $item ) {
+                                       $feed->outItem( $item );
+                               }
                        }
-                       $dbr->freeResult( $res );
 
                        $feed->outFooter();
                        return true;
@@ -475,14 +647,14 @@ class QueryPage {
         * feedItemDesc()
         */
        function feedResult( $row ) {
-               if( !isset( $row->title ) ) {
-                       return NULL;
+               if ( !isset( $row->title ) ) {
+                       return null;
                }
                $title = Title::MakeTitle( intval( $row->namespace ), $row->title );
-               if( $title ) {
+               if ( $title ) {
                        $date = isset( $row->timestamp ) ? $row->timestamp : '';
                        $comments = '';
-                       if( $title ) {
+                       if ( $title ) {
                                $talkpage = $title->getTalkPage();
                                $comments = $talkpage->getFullURL();
                        }
@@ -493,9 +665,9 @@ class QueryPage {
                                $title->getFullURL(),
                                $date,
                                $this->feedItemAuthor( $row ),
-                               $comments);
+                               $comments );
                } else {
-                       return NULL;
+                       return null;
                }
        }
 
@@ -508,14 +680,14 @@ class QueryPage {
        }
 
        function feedTitle() {
-               global $wgContLanguageCode, $wgSitename;
+               global $wgLanguageCode, $wgSitename;
                $page = SpecialPage::getPage( $this->getName() );
                $desc = $page->getDescription();
-               return "$wgSitename - $desc [$wgContLanguageCode]";
+               return "$wgSitename - $desc [$wgLanguageCode]";
        }
 
        function feedDesc() {
-               return wfMsg( 'tagline' );
+               return wfMsgExt( 'tagline', 'parsemag' );
        }
 
        function feedUrl() {
@@ -524,4 +696,96 @@ class QueryPage {
        }
 }
 
-?>
\ No newline at end of file
+/**
+ * Class definition for a wanted query page like
+ * WantedPages, WantedTemplates, etc
+ */
+abstract class WantedQueryPage extends QueryPage {
+
+       function isExpensive() {
+               return true;
+       }
+
+       function isSyndicated() {
+               return false;
+       }
+
+       /**
+        * Cache page existence for performance
+        */
+       function preprocessResults( $db, $res ) {
+               $batch = new LinkBatch;
+               foreach ( $res as $row ) {
+                       $batch->add( $row->namespace, $row->title );
+               }
+               $batch->execute();
+
+               // Back to start for display
+               if ( $db->numRows( $res ) > 0 )
+                       // If there are no rows we get an error seeking.
+                       $db->dataSeek( $res, 0 );
+       }
+
+       /**
+        * Should formatResult() always check page existence, even if
+        * the results are fresh?  This is a (hopefully temporary)
+        * kluge for Special:WantedFiles, which may contain false
+        * positives for files that exist e.g. in a shared repo (bug
+        * 6220).
+        */
+       function forceExistenceCheck() {
+               return false;
+       }
+
+       /**
+        * Format an individual result
+        *
+        * @param $skin Skin to use for UI elements
+        * @param $result Result row
+        * @return string
+        */
+       public function formatResult( $skin, $result ) {
+               $title = Title::makeTitleSafe( $result->namespace, $result->title );
+               if ( $title instanceof Title ) {
+                       if ( $this->isCached() || $this->forceExistenceCheck() ) {
+                               $pageLink = $title->isKnown()
+                                       ? '<del>' . $skin->link( $title ) . '</del>'
+                                       : $skin->link(
+                                               $title,
+                                               null,
+                                               array(),
+                                               array(),
+                                               array( 'broken' )
+                                       );
+                       } else {
+                               $pageLink = $skin->link(
+                                       $title,
+                                       null,
+                                       array(),
+                                       array(),
+                                       array( 'broken' )
+                               );
+                       }
+                       return wfSpecialList( $pageLink, $this->makeWlhLink( $title, $skin, $result ) );
+               } else {
+                       $tsafe = htmlspecialchars( $result->title );
+                       return wfMsgHtml( 'wantedpages-badtitle', $tsafe );
+               }
+       }
+
+       /**
+        * Make a "what links here" link for a given title
+        *
+        * @param $title Title to make the link for
+        * @param $skin Skin object to use
+        * @param $result Object: result row
+        * @return string
+        */
+       private function makeWlhLink( $title, $skin, $result ) {
+               global $wgLang;
+               $wlh = SpecialPage::getTitleFor( 'Whatlinkshere' );
+               $label = wfMsgExt( 'nlinks', array( 'parsemag', 'escape' ),
+               $wgLang->formatNum( $result->value ) );
+               return $skin->link( $wlh, $label, array(), array( 'target' => $title->getPrefixedText() ) );
+       }
+}