Merge "Fix spelling mistakes in comments"

[lhc/web/wiklou.git] / includes / specialpage / QueryPage.php

diff --git a/includes/specialpage/QueryPage.php b/includes/specialpage/QueryPage.php
index bfb29ae..9755e8e 100644 (file)
--- a/includes/specialpage/QueryPage.php
+++ b/includes/specialpage/QueryPage.php
@@ -473,12 +473,37 @@ abstract class QueryPage extends SpecialPage {
         * Returns limit and offset, as returned by $this->getRequest()->getLimitOffset().
         * Subclasses may override this to further restrict or modify limit and offset.
         *
+        * @note Restricts the offset parameter, as most query pages have inefficient paging
         * @since 1.26
         *
         * @return int[] list( $limit, $offset )
         */
        protected function getLimitOffset() {
-               return $this->getRequest()->getLimitOffset();
+               list( $limit, $offset ) = $this->getRequest()->getLimitOffset();
+               if ( !$this->getConfig()->get( 'MiserMode' ) ) {
+                       $maxResults = $this->getMaxResults();
+                       // Can't display more than max results on a page
+                       $limit = min( $limit, $maxResults );
+                       // Can't skip over more than $maxResults
+                       $offset = min( $offset, $maxResults );
+                       // Can't let $offset + $limit > $maxResults
+                       $limit = min( $limit, $maxResults - $offset );
+               }
+               return array( $limit, $offset );
+       }
+
+       /**
+        * Get max number of results we can return in miser mode.
+        *
+        * Most QueryPage subclasses use inefficient paging, so limit the max amount we return
+        * This matters for uncached query pages that might otherwise accept an offset of 3 million
+        *
+        * @since 1.27
+        * @return int
+        */
+       protected function getMaxResults() {
+               // Max of 10000, unless we store more than 5000 in query cache.
+               return max( $this->getConfig()->get( 'QueryCacheLimit' ), 10000 );
        }
 
        /**
@@ -562,8 +587,10 @@ abstract class QueryPage extends SpecialPage {
                                        min( $this->numRows, $this->limit ), # do not show the one extra row, if exist
                                        $this->offset + 1, ( min( $this->numRows, $this->limit ) + $this->offset ) )->parseAsBlock() );
                                # Disable the "next" link when we reach the end
+                               $atEnd = ( $this->numRows <= $this->limit )
+                                       || ( $this->offset + $this-> limit  >= $this->getMaxResults() );
                                $paging = $this->getLanguage()->viewPrevNext( $this->getPageTitle( $par ), $this->offset,
-                                       $this->limit, $this->linkParameters(), ( $this->numRows <= $this->limit ) );
+                                       $this->limit, $this->linkParameters(), $atEnd );
                                $out->addHTML( '<p>' . $paging . '</p>' );
                        } else {
                                # No results to show, so don't bother with "showing X of Y" etc.