--- loncom/interface/domainprefs.pm	2019/04/26 20:15:30	1.355
+++ loncom/interface/domainprefs.pm	2019/04/26 20:22:18	1.356
@@ -1,7 +1,7 @@
 # The LearningOnline Network with CAPA
 # Handler to set domain-wide configuration settings
 #
-# $Id: domainprefs.pm,v 1.355 2019/04/26 20:15:30 raeburn Exp $
+# $Id: domainprefs.pm,v 1.356 2019/04/26 20:22:18 raeburn Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -5822,6 +5822,7 @@ sub print_passwords {
         max            => 'Maximum password length',
         chars          => 'Required characters',
         expire         => 'Password expiration (days)',
+        numsaved       => 'Number of previous passwords to save and disallow reuse',
     );
     if ($position eq 'top') {
         my ($othertitle,$usertypes,$types) = &Apache::loncommon::sorted_inst_types($dom);
@@ -6085,7 +6086,7 @@ sub print_passwords {
             $itemcount ++;
         }
     } elsif ($position eq 'lower') {
-        my ($min,$max,%chars,$expire);
+        my ($min,$max,%chars,$expire,$numsaved);
         if (ref($settings) eq 'HASH') {
             if ($settings->{min}) {
                 $min = $settings->{min};
@@ -6099,6 +6100,9 @@ sub print_passwords {
             if ($settings->{expire}) {
                 $expire = $settings->{expire};
             }
+            if ($settings->(numsaved}) {
+                $numsaved = $settings->(numsaved};
+            }
         } else {
             $min = '7';
         }
@@ -6161,6 +6165,13 @@ sub print_passwords {
                       '<input type="text" name="passwords_expire" value="'.$expire.'" size="4" />'.
                       '<span class="LC_fontsize_small"> '.&mt('(Leave blank for no expiration)').'</span>'.
                       '</span></td></tr>';
+        $itemcount ++;
+        $css_class = $itemcount%2?' class="LC_odd_row"':'';
+        $datatable .= '<tr'.$css_class.'><td>'.$titles{'numsaved'}.'</td>'.
+                      '<td class="LC_left_item"><span class="LC_nobreak">'.
+                      '<input type="text" name="passwords_numsaved" value="'.$numsaved.'" size="3" />'.
+                      '<span class="LC_fontsize_small"> '.&mt('(Leave blank to not save previous passwords)').'</span>'.
+                      '</span></td></tr>';
     } else {
         my $checkedon;
         my $checkedoff = ' checked="checked"';
@@ -13984,6 +13995,7 @@ sub modify_passwords {
         max            => 'Maximum password length',
         chars          => 'Required characters',
         expire         => 'Password expiration (days)',
+        numsaved       => 'Number of previous passwords to save',
         reset          => 'Resetting Forgotten Password',
         intauth        => 'Encryption of Stored Passwords (Internal Auth)',
         rules          => 'Rules for LON-CAPA Passwords',
@@ -14191,9 +14203,17 @@ sub modify_passwords {
             $updatedefaults = 1;
         }
     }
-    foreach my $rule ('min','max','expire') {
+    foreach my $rule ('min','max','expire','numsaved') {
         $env{'form.passwords_'.$rule} =~ s/^\s+|\s+$//g;
-        if ($env{'form.passwords_'.$rule} =~ /^(|\d+(|\.\d*))$/) {
+        my $ruleok;
+        if ($rule eq 'expire') {
+            if ($env{'form.passwords_'.$rule} =~ /^\d+(|\.\d*)$/) {
+                $ruleok = 1; 
+            }
+        } elsif ($env{'form.passwords_'.$rule} =~ /^\d+$/) {
+            $ruleok = 1;
+        }
+        if ($ruleok) {
             $newvalues{$rule} = $env{'form.passwords_'.$rule};
             if (exists($current{$rule})) {
                 if ($newvalues{$rule} ne $current{$rule}) {
@@ -14373,13 +14393,14 @@ sub modify_passwords {
                             $resulttext .= '<li>'.&mt('[_1] set to "[_2]"',$titles{$key.'_'.$item},$value).'</li>';
                         }
                     } elsif ($key eq 'rules') {
-                        foreach my $rule ('min','max','expire') {
+                        foreach my $rule ('min','max','expire','numsaved') {
                             if ($confighash{'passwords'}{$rule} eq '') {
-                                $resulttext .= '<li>'.&mt('[_1] not set.',$titles{$rule});
                                 if ($rule eq 'min') {
-                                   $resulttext .= ' '.&mt('Default of 7 will be used');
+                                    $resulttext .= '<li>'.&mt('[_1] not set.',$titles{$rule});
+                                                   ' '.&mt('Default of 7 will be used').'</li>';
+                                } else {
+                                    $resulttext .= '<li>'.&mt('[_1] set to none',$titles{$rule}).'</li>';
                                 }
-                                $resulttext .= '</li>';
                             } else {
                                 $resulttext .= '<li>'.&mt('[_1] set to [_2]',$titles{$rule},$confighash{'passwords'}{$rule}).'</li>';
                             }