Robustness - avoid possible divide by zero problem MDL-7425

course/category.php

@@ -328,7 +328,11 @@
         // be moved up and down beyond the paging border
         if ($totalcount > $perpage) {
             $atfirstpage = ($page == 0);
-            $atlastpage = (($page + 1) == ceil($totalcount / $perpage));
+            if ($perpage > 0) {
+                $atlastpage = (($page + 1) == ceil($totalcount / $perpage));
+            } else {
+                $atlastpage = true;
+            }
         } else {
             $atfirstpage = true;
             $atlastpage = true;

lib/weblib.php

@@ -5334,7 +5334,11 @@ function print_paging_bar($totalcount, $page, $perpage, $baseurl, $pagevar='page
             $pagenum = $page - 1;
             $output .= '&nbsp;(<a  href="'. $baseurl . $pagevar .'='. $pagenum .'">'. get_string('previous') .'</a>)&nbsp;';
         }
-        $lastpage = ceil($totalcount / $perpage);
+        if ($perpage > 0) {
+            $lastpage = ceil($totalcount / $perpage);
+        } else {
+            $lastpage = 1;
+        }
         if ($page > 15) {
             $startpage = $page - 10;
             $output .= '&nbsp;<a href="'. $baseurl . $pagevar .'=0">1</a>&nbsp;...';