better check for freshness

diff --git a/mkgallery.pl b/mkgallery.pl
index 822cd49845d1f900e40ef0c54d0911df1cdfc936..a0cb8eebef6089317ae33056ddfef89ca91737e7 100755 (executable)
--- a/mkgallery.pl
+++ b/mkgallery.pl
@@ -108,6 +108,7 @@ sub iterate {
        my $fullpath .= $self->{-fullpath};
        print "iterate in dir $fullpath\n" if ($debug);
 
+       my $youngest=0;
        my @rdirlist;
        my @rimglist;
        my $D;
@@ -121,6 +122,8 @@ sub iterate {
                if ($child->isdir) {
                        push(@rdirlist,$child);
                } elsif ($child->isimg) {
+                       my @stat = stat($child->{-fullpath});
+                       $youngest = $stat[9] if ($youngest < $stat[9]);
                        push(@rimglist,$child);
                }
        }
@@ -144,6 +147,12 @@ sub iterate {
                $dir->iterate;
        }
 
+# no need to go beyond this point if the directory timestamp did not
+# change since we built index.html file last time.
+
+       my @istat = stat($self->{-fullpath}.'/index.html');
+       return unless ($youngest > $istat[9]);
+
 # 3. iterate through images to build cross-links,
 
        my $previmg = undef;
@@ -361,80 +370,87 @@ sub makeaux {
        # slideshow
        for my $refresh('static', 'slide') {
                my $fn = sprintf("%s/.html/%s-%s.html",$dn,$name,$refresh);
-               my $imgsrc = '../'.$self->{$sizes[1]};
-               my $fwdref;
-               my $bakref;
-               if ($nref) {
-                       $fwdref = sprintf("%s-%s.html",$nref,$refresh);
-               } else {
-                       $fwdref = '../index.html';
-               }
-               if ($pref) {
-                       $bakref = sprintf("%s-%s.html",$pref,$refresh);
-               } else {
-                       $bakref = '../index.html';
-               }
-               my $toggleref;
-               my $toggletext;
-               if ($refresh eq 'slide') {
-                       $toggleref=sprintf("%s-static.html",$name);
-                       $toggletext = 'Stop!';
-               } else {
-                       $toggleref=sprintf("%s-slide.html",$name);
-                       $toggletext = 'Play-&gt;';
-               }
-               my $F;
-               unless (open($F,'>'.$fn)) {
-                       warn "cannot open \"$fn\": $!";
-                       next;
-               }
-               if ($refresh eq 'slide') {
-                       print $F start_html(-title=>$title,
+               if (isnewer($self->{-fullpath},$fn)) {
+                       my $imgsrc = '../'.$self->{$sizes[1]};
+                       my $fwdref;
+                       my $bakref;
+                       if ($nref) {
+                               $fwdref = sprintf("%s-%s.html",$nref,$refresh);
+                       } else {
+                               $fwdref = '../index.html';
+                       }
+                       if ($pref) {
+                               $bakref = sprintf("%s-%s.html",$pref,$refresh);
+                       } else {
+                               $bakref = '../index.html';
+                       }
+                       my $toggleref;
+                       my $toggletext;
+                       if ($refresh eq 'slide') {
+                               $toggleref=sprintf("%s-static.html",$name);
+                               $toggletext = 'Stop!';
+                       } else {
+                               $toggleref=sprintf("%s-slide.html",$name);
+                               $toggletext = 'Play-&gt;';
+                       }
+                       my $F;
+                       unless (open($F,'>'.$fn)) {
+                               warn "cannot open \"$fn\": $!";
+                               next;
+                       }
+                       if ($refresh eq 'slide') {
+                               print $F start_html(
+                                       -title=>$title,
                                        -bgcolor=>"#808080",
                                        -head=>meta({-http_equiv=>'Refresh',
                                                -content=>"3; url=$fwdref"}),
                                        -style=>{-src=>$inc."gallery.css"},
-                               ),"\n";
-                                       
-               } else {
-                       print $F start_html(-title=>$title,
+                                       ),"\n";
+                                               
+                       } else {
+                               print $F start_html(-title=>$title,
                                        -bgcolor=>"#808080",
                                        -style=>{-src=>$inc."gallery.css"},
-                               ),"\n";
+                                       ),"\n";
+                       }
+                       print $F start_center,"\n",
+                               h1($title),"\n",
+                               start_table({-class=>'navi'}),start_Tr,"\n",
+                               td(a({-href=>"../index.html"},"Index")),"\n",
+                               td(a({-href=>$bakref},"&lt;&lt;Prev")),"\n",
+                               td(a({-href=>$toggleref},$toggletext)),"\n",
+                               td(a({-href=>$fwdref},"Next&gt;&gt;")),"\n",
+                               end_Tr,
+                               end_table,"\n",
+                               table({-class=>'picframe'},
+                                       Tr(td(img({-src=>$imgsrc})))),"\n",
+                               end_center,"\n",
+                               end_html,"\n";
+                       close($F);
+               }
+       }
+
+       # info html
+       my $fn = sprintf("%s/.html/%s-info.html",$dn,$name);
+       if (isnewer($self->{-fullpath},$fn)) {
+               my $F;
+               unless (open($F,'>'.$fn)) {
+                       warn "cannot open \"$fn\": $!";
+                       return;
                }
-               print $F start_center,"\n",
+               my $imgsrc = sprintf("../.%s/%s",$sizes[0],$name);
+               print $F start_html(-title=>$title,
+                               -style=>{-src=>$inc."gallery.css"},),"\n",
+                       start_center,"\n",
                        h1($title),"\n",
-                       start_table({-class=>'navi'}),start_Tr,"\n",
-                       td(a({-href=>"../index.html"},"Index")),"\n",
-                       td(a({-href=>$bakref},"&lt;&lt;Prev")),"\n",
-                       td(a({-href=>$toggleref},$toggletext)),"\n",
-                       td(a({-href=>$fwdref},"Next&gt;&gt;")),"\n",
-                       end_Tr,
-                       end_table,"\n",
-                       table({-class=>'picframe'},
-                               Tr(td(img({-src=>$imgsrc})))),"\n",
+                       table({-class=>'ipage'},
+                               Tr(td(img({-src=>$imgsrc})),
+                                       td($self->infotable))),
+                       a({-href=>'../index.html'},'Index'),"\n",
                        end_center,"\n",
                        end_html,"\n";
                close($F);
        }
-       my $fn = sprintf("%s/.html/%s-info.html",$dn,$name);
-       my $F;
-       unless (open($F,'>'.$fn)) {
-               warn "cannot open \"$fn\": $!";
-               return;
-       }
-
-       # info html
-       my $imgsrc = sprintf("../.%s/%s",$sizes[0],$name);
-       print $F start_html(-title=>$title,
-                               -style=>{-src=>$inc."gallery.css"},),"\n",
-               start_center,"\n",
-               h1($title),"\n",
-               table({-class=>'ipage'},Tr(td(img({-src=>$imgsrc})),td($self->infotable))),
-               a({-href=>'../index.html'},'Index'),"\n",
-               end_center,"\n",
-               end_html,"\n";
-       close($F);
 }
 
 sub startindex {