gitweb: Fix "Use of unitialized value" warnings in empty repository

Fix it so gitweb doesn't write "Use of unitialized value..." warnings
(which gets written in web server logs) for empty (no commits)
repository.

In empty repository "last change" (last activity) doesn't make sense;
also there is no sense in parsing commits which aren't there.

In projects list for empty repositories gitweb now writes "No commits"
using "noage" class, instead of leaving cell empty, in the last change
column.

Signed-off-by: Jakub Narebski <jnareb@gmail.com>
Signed-off-by: Junio C Hamano <junkio@cox.net>

gitweb/gitweb.perl

@@ -728,7 +728,9 @@ sub chop_str {
 sub age_class {
 	my $age = shift;
 
-	if ($age < 60*60*2) {
+	if (!defined $age) {
+		return "noage";
+	} elsif ($age < 60*60*2) {
 		return "age0";
 	} elsif ($age < 60*60*24*2) {
 		return "age1";
@@ -1258,7 +1260,8 @@ sub git_get_last_activity {
 	     'refs/heads') or return;
 	my $most_recent = <$fd>;
 	close $fd or return;
-	if ($most_recent =~ / (\d+) [-+][01]\d\d\d$/) {
+	if (defined $most_recent &&
+	    $most_recent =~ / (\d+) [-+][01]\d\d\d$/) {
 		my $timestamp = $1;
 		my $age = time - $timestamp;
 		return ($age, age_string($age));
@@ -2983,7 +2986,7 @@ sub git_project_list_body {
 		                        esc_html($pr->{'descr'})) . "</td>\n" .
 		      "<td><i>" . chop_str($pr->{'owner'}, 15) . "</i></td>\n";
 		print "<td class=\"". age_class($pr->{'age'}) . "\">" .
-		      $pr->{'age_string'} . "</td>\n" .
+		      (defined $pr->{'age_string'} ? $pr->{'age_string'} : "No commits") . "</td>\n" .
 		      "<td class=\"link\">" .
 		      $cgi->a({-href => href(project=>$pr->{'path'}, action=>"summary")}, "summary")   . " | " .
 		      $cgi->a({-href => href(project=>$pr->{'path'}, action=>"shortlog")}, "shortlog") . " | " .
@@ -3335,7 +3338,7 @@ sub git_project_index {
 sub git_summary {
 	my $descr = git_get_project_description($project) || "none";
 	my %co = parse_commit("HEAD");
-	my %cd = parse_date($co{'committer_epoch'}, $co{'committer_tz'});
+	my %cd = %co ? parse_date($co{'committer_epoch'}, $co{'committer_tz'}) : ();
 	my $head = $co{'id'};
 
 	my $owner = git_get_project_owner($project);
@@ -3358,8 +3361,11 @@ sub git_summary {
 	print "<div class=\"title\">&nbsp;</div>\n";
 	print "<table cellspacing=\"0\">\n" .
 	      "<tr><td>description</td><td>" . esc_html($descr) . "</td></tr>\n" .
-	      "<tr><td>owner</td><td>$owner</td></tr>\n" .
-	      "<tr><td>last change</td><td>$cd{'rfc2822'}</td></tr>\n";
+	      "<tr><td>owner</td><td>$owner</td></tr>\n";
+	if (defined $cd{'rfc2822'}) {
+		print "<tr><td>last change</td><td>$cd{'rfc2822'}</td></tr>\n";
+	}
+
 	# use per project git URL list in $projectroot/$project/cloneurl
 	# or make project git URL from git base URL and project name
 	my $url_tag = "URL";
@@ -3382,11 +3388,13 @@ sub git_summary {
 
 	# we need to request one more than 16 (0..15) to check if
 	# those 16 are all
-	my @commitlist = parse_commits($head, 17);
-	git_print_header_div('shortlog');
-	git_shortlog_body(\@commitlist, 0, 15, $refs,
-	                  $#commitlist <=  15 ? undef :
-	                  $cgi->a({-href => href(action=>"shortlog")}, "..."));
+	my @commitlist = $head ? parse_commits($head, 17) : ();
+	if (@commitlist) {
+		git_print_header_div('shortlog');
+		git_shortlog_body(\@commitlist, 0, 15, $refs,
+		                  $#commitlist <=  15 ? undef :
+		                  $cgi->a({-href => href(action=>"shortlog")}, "..."));
+	}
 
 	if (@taglist) {
 		git_print_header_div('tags');