printf qq!<div class="pre"><a id="l%i" href="%s#l%i" class="linenr">%4i</a> %s</div>\n!,
			       $nr, esc_attr(href(-replay => 1)), $nr, $nr,
			       $highlight ? sanitize($line) : esc_html($line, -nbsp=>1);
		}
	}
	close $fd
		or print "Reading blob failed.\n";
	print "</div>";
	git_footer_html();
}

sub git_tree {
	if (!defined $hash_base) {
		$hash_base = "HEAD";
	}
	if (!defined $hash) {
		if (defined $file_name) {
			$hash = git_get_hash_by_path($hash_base, $file_name, "tree");
		} else {
			$hash = $hash_base;
		}
	}
	die_error(404, "No such tree") unless defined($hash);

	my $show_sizes = gitweb_check_feature('show-sizes');
	my $have_blame = gitweb_check_feature('blame');

	my @entries = ();
	{
		local $/ = "\0";
		open my $fd, "-|", git_cmd(), "ls-tree", '-z',
			($show_sizes ? '-l' : ()), @extra_options, $hash
			or die_error(500, "Open git-ls-tree failed");
		@entries = map { chomp; $_ } <$fd>;
		close $fd
			or die_error(404, "Reading tree failed");
	}

	my $refs = git_get_references();
	my $ref = format_ref_marker($refs, $hash_base);
	git_header_html();
	my $basedir = '';
	if (defined $hash_base && (my %co = parse_commit($hash_base))) {
		my @views_nav = ();
		if (defined $file_name) {
			push @views_nav,
				$cgi->a({-href => href(action=>"history", -replay=>1)},
				        "history"),
				$cgi->a({-href => href(action=>"tree",
				                       hash_base=>"HEAD", file_name=>$file_name)},
				        "HEAD"),
		}
		my $snapshot_links = format_snapshot_links($hash);
		if (defined $snapshot_links) {
			# FIXME: Should be available when we have no hash base as well.
			push @views_nav, $snapshot_links;
		}
		git_print_page_nav('tree','', $hash_base, undef, undef,
		                   join(' | ', @views_nav));
		git_print_header_div('commit', esc_html($co{'title'}) . $ref, $hash_base);
	} else {
		undef $hash_base;
		print "<div class=\"page_nav\">\n";
		print "<br/><br/></div>\n";
		print "<div class=\"title\">".esc_html($hash)."</div>\n";
	}
	if (defined $file_name) {
		$basedir = $file_name;
		if ($basedir ne '' && substr($basedir, -1) ne '/') {
			$basedir .= '/';
		}
		git_print_page_path($file_name, 'tree', $hash_base);
	}
	print "<div class=\"page_body\">\n";
	print "<table class=\"tree\">\n";
	my $alternate = 1;
	# '..' (top directory) link if possible
	if (defined $hash_base &&
	    defined $file_name && $file_name =~ m![^/]+$!) {
		if ($alternate) {
			print "<tr class=\"dark\">\n";
		} else {
			print "<tr class=\"light\">\n";
		}
		$alternate ^= 1;

		my $up = $file_name;
		$up =~ s!/?[^/]+$!!;
		undef $up unless $up;
		# based on git_print_tree_entry
		print '<td class="mode">' . mode_str('040000') . "</td>\n";
		print '<td class="size">&nbsp;</td>'."\n" if $show_sizes;
		print '<td class="list">';
		print $cgi->a({-href => href(action=>"tree",
		                             hash_base=>$hash_base,
		                             file_name=>$up)},
		              "..");
		print "</td>\n";
		print "<td class=\"link\"></td>\n";

		print "</tr>\n";
	}
	foreach my $line (@entries) {
		my %t = parse_ls_tree_line($line, -z => 1, -l => $show_sizes);

		if ($alternate) {
			print "<tr class=\"dark\">\n";
		} else {
			print "<tr class=\"light\">\n";
		}
		$alternate ^= 1;

		git_print_tree_entry(\%t, $basedir, $hash_base, $have_blame);

		print "</tr>\n";
	}
	print "</table>\n" .
	      "</div>";
	git_footer_html();
}

sub sanitize_for_filename {
    my $name = shift;

    $name =~ s!/!-!g;
    $name =~ s/[^[:alnum:]_.-]//g;

    return $name;
}

sub snapshot_name {
	my ($project, $hash) = @_;

	# path/to/project.git  -> project
	# path/to/project/.git -> project
	my $name = to_utf8($project);
	$name =~ s,([^/])/*\.git$,$1,;
	$name = sanitize_for_filename(basename($name));

	my $ver = $hash;
	if ($hash =~ /^[0-9a-fA-F]+$/) {
		# shorten SHA-1 hash
		my $full_hash = git_get_full_hash($project, $hash);
		if ($full_hash =~ /^$hash/ && length($hash) > 7) {
			$ver = git_get_short_hash($project, $hash);
		}
	} elsif ($hash =~ m!^refs/tags/(.*)$!) {
		# tags don't need shortened SHA-1 hash
		$ver = $1;
	} else {
		# branches and other need shortened SHA-1 hash
		my $strip_refs = join '|', map { quotemeta } get_branch_refs();
		if ($hash =~ m!^refs/($strip_refs|remotes)/(.*)$!) {
			my $ref_dir = (defined $1) ? $1 : '';
			$ver = $2;

			$ref_dir = sanitize_for_filename($ref_dir);
			# for refs neither in heads nor remotes we want to
			# add a ref dir to archive name
			if ($ref_dir ne '' and $ref_dir ne 'heads' and $ref_dir ne 'remotes') {
				$ver = $ref_dir . '-' . $ver;
			}
		}
		$ver .= '-' . git_get_short_hash($project, $hash);
	}
	# special case of sanitization for filename - we change
	# slashes to dots instead of dashes
	# in case of hierarchical branch names
	$ver =~ s!/!.!g;
	$ver =~ s/[^[:alnum:]_.-]//g;

	# name = project-version_string
	$name = "$name-$ver";

	return wantarray ? ($name, $name) : $name;
}

sub exit_if_unmodified_since {
	my ($latest_epoch) = @_;
	our $cgi;

	my $if_modified = $cgi->http('IF_MODIFIED_SINCE');
	if (defined $if_modified) {
		my $since;
		if (eval { require HTTP::Date; 1; }) {
			$since = HTTP::Date::str2time($if_modified);
		} elsif (eval { require Time::ParseDate; 1; }) {
			$since = Time::ParseDate::parsedate($if_modified, GMT => 1);
		}
		if (defined $since && $latest_epoch <= $since) {
			my %latest_date = parse_date($latest_epoch);
			print $cgi->header(
				-last_modified => $latest_date{'rfc2822'},
				-status => '304 Not Modified');
			goto DONE_GITWEB;
		}
	}
}

sub git_snapshot {
	my $format = $input_params{'snapshot_format'};
	if (!@snapshot_fmts) {
		die_error(403, "Snapshots not allowed");
	}
	# default to first supported snapshot format
	$format ||= $snapshot_fmts[0];
	if ($format !~ m/^[a-z0-9]+$/) {
		die_error(400, "Invalid snapshot format parameter");
	} elsif (!exists($known_snapshot_formats{$format})) {
		die_error(400, "Unknown snapshot format");
	} elsif ($known_snapshot_formats{$format}{'disabled'}) {
		die_error(403, "Snapshot format not allowed");
	} elsif (!grep($_ eq $format, @snapshot_fmts)) {
		die_error(403, "Unsupported snapshot format");
	}

	my $type = git_get_type("$hash^{}");
	if (!$type) {
		die_error(404, 'Object does not exist');
	}  elsif ($type eq 'blob') {
		die_error(400, 'Object is not a tree-ish');
	}

	my ($name, $prefix) = snapshot_name($project, $hash);
	my $filename = "$name$known_snapshot_formats{$format}{'suffix'}";

	my %co = parse_commit($hash);
	exit_if_unmodified_since($co{'committer_epoch'}) if %co;

	my $cmd = quote_command(
		git_cmd(), 'archive',
		"--format=$known_snapshot_formats{$format}{'format'}",
		"--prefix=$prefix/", $hash);
	if (exists $known_snapshot_formats{$format}{'compressor'}) {
		$cmd .= ' | ' . quote_command(@{$known_snapshot_formats{$format}{'compressor'}});
	}

	$filename =~ s/(["\\])/\\$1/g;
	my %latest_date;
	if (%co) {
		%latest_date = parse_date($co{'committer_epoch'}, $co{'committer_tz'});
	}

	print $cgi->header(
		-type => $known_snapshot_formats{$format}{'type'},
		-content_disposition => 'inline; filename="' . $filename . '"',
		%co ? (-last_modified => $latest_date{'rfc2822'}) : (),
		-status => '200 OK');

	open my $fd, "-|", $cmd
		or die_error(500, "Execute git-archive failed");
	binmode STDOUT, ':raw';
	print <$fd>;
	binmode STDOUT, ':utf8'; # as set at the beginning of gitweb.cgi
	close $fd;
}

sub git_log_generic {
	my ($fmt_name, $body_subr, $base, $parent, $file_name, $file_hash) = @_;

	my $head = git_get_head_hash($project);
	if (!defined $base) {
		$base = $head;
	}
	if (!defined $page) {
		$page = 0;
	}
	my $refs = git_get_references();

	my $commit_hash = $base;
	if (defined $parent) {
		$commit_hash = "$parent..$base";
	}
	my @commitlist =
		parse_commits($commit_hash, 101, (100 * $page),
		              defined $file_name ? ($file_name, "--full-history") : ());

	my $ftype;
	if (!defined $file_hash && defined $file_name) {
		# some commits could have deleted file in question,
		# and not have it in tree, but one of them has to have it
		for (my $i = 0; $i < @commitlist; $i++) {
			$file_hash = git_get_hash_by_path($commitlist[$i]{'id'}, $file_name);
			last if defined $file_hash;
		}
	}
	if (defined $file_hash) {
		$ftype = git_get_type($file_hash);
	}
	if (defined $file_name && !defined $ftype) {
		die_error(500, "Unknown type of object");
	}
	my %co;
	if (defined $file_name) {
		%co = parse_commit($base)
			or die_error(404, "Unknown commit object");
	}


	my $paging_nav = format_paging_nav($fmt_name, $page, $#commitlist >= 100);
	my $next_link = '';
	if ($#commitlist >= 100) {
		$next_link =
			$cgi->a({-href => href(-replay=>1, page=>$page+1),
			         -accesskey => "n", -title => "Alt-n"}, "next");
	}
	my $patch_max = gitweb_get_feature('patches');
	if ($patch_max && !defined $file_name) {
		if ($patch_max < 0 || @commitlist <= $patch_max) {
			$paging_nav .= " &sdot; " .
				$cgi->a({-href => href(action=>"patches", -replay=>1)},
					"patches");
		}
	}

	git_header_html();
	git_print_page_nav($fmt_name,'', $hash,$hash,$hash, $paging_nav);
	if (defined $file_name) {
		git_print_header_div('commit', esc_html($co{'title'}), $base);
	} else {
		git_print_header_div('summary', $project)
	}
	git_print_page_path($file_name, $ftype, $hash_base)
		if (defined $file_name);

	$body_subr->(\@commitlist, 0, 99, $refs, $next_link,
	             $file_name, $file_hash, $ftype);

	git_footer_html();
}

sub git_log {
	git_log_generic('log', \&git_log_body,
	                $hash, $hash_parent);
}

sub git_commit {
	$hash ||= $hash_base || "HEAD";
	my %co = parse_commit($hash)
	    or die_error(404, "Unknown commit object");

	my $parent  = $co{'parent'};
	my $parents = $co{'parents'}; # listref

	# we need to prepare $formats_nav before any parameter munging
	my $formats_nav;
	if (!defined $parent) {
		# --root commitdiff
		$formats_nav .= '(initial)';
	} elsif (@$parents == 1) {
		# single parent commit
		$formats_nav .=
			'(parent: ' .
			$cgi->a({-href => href(action=>"commit",
			                       hash=>$parent)},
			        esc_html(substr($parent, 0, 7))) .
			')';
	} else {
		# merge commit
		$formats_nav .=
			'(merge: ' .
			join(' ', map {
				$cgi->a({-href => href(action=>"commit",
				                       hash=>$_)},
				        esc_html(substr($_, 0, 7)));
			} @$parents ) .
			')';
	}
	if (gitweb_check_feature('patches') && @$parents <= 1) {
		$formats_nav .= " | " .
			$cgi->a({-href => href(action=>"patch", -replay=>1)},
				"patch");
	}

	if (!defined $parent) {
		$parent = "--root";
	}
	my @difftree;
	open my $fd, "-|", git_cmd(), "diff-tree", '-r', "--no-commit-id",
		@diff_opts,
		(@$parents <= 1 ? $parent : '-c'),
		$hash, "--"
		or die_error(500, "Open git-diff-tree failed");
	@difftree = map { chomp; $_ } <$fd>;
	close $fd or die_error(404, "Reading git-diff-tree failed");

	# non-textual hash id's can be cached
	my $expires;
	if ($hash =~ m/^[0-9a-fA-F]{40}$/) {
		$expires = "+1d";
	}
	my $refs = git_get_references();
	my $ref = format_ref_marker($refs, $co{'id'});

	git_header_html(undef, $expires);
	git_print_page_nav('commit', '',
	                   $hash, $co{'tree'}, $hash,
	                   $formats_nav);

	if (defined $co{'parent'}) {
		git_print_header_div('commitdiff', esc_html($co{'title'}) . $ref, $hash);
	} else {
		git_print_header_div('tree', esc_html($co{'title'}) . $ref, $co{'tree'}, $hash);
	}
	print "<div class=\"title_text\">\n" .
	      "<table class=\"object_header\">\n";
	git_print_authorship_rows(\%co);
	print "<tr><td>commit</td><td class=\"sha1\">$co{'id'}</td></tr>\n";
	print "<tr>" .
	      "<td>tree</td>" .
	      "<td class=\"sha1\">" .
	      $cgi->a({-href => href(action=>"tree", hash=>$co{'tree'}, hash_base=>$hash),
	               class => "list"}, $co{'tree'}) .
	      "</td>" .
	      "<td class=\"link\">" .
	      $cgi->a({-href => href(action=>"tree", hash=>$co{'tree'}, hash_base=>$hash)},
	              "tree");
	my $snapshot_links = format_snapshot_links($hash);
	if (defined $snapshot_links) {
		print " | " . $snapshot_links;
	}
	print "</td>" .
	      "</tr>\n";

	foreach my $par (@$parents) {
		print "<tr>" .
		      "<td>parent</td>" .
		      "<td class=\"sha1\">" .
		      $cgi->a({-href => href(action=>"commit", hash=>$par),
		               class => "list"}, $par) .
		      "</td>" .
		      "<td class=\"link\">" .
		      $cgi->a({-href => href(action=>"commit", hash=>$par)}, "commit") .
		      " | " .
		      $cgi->a({-href => href(action=>"commitdiff", hash=>$hash, hash_parent=>$par)}, "diff") .
		      "</td>" .
		      "</tr>\n";
	}
	print "</table>".
	      "</div>\n";

	print "<div class=\"page_body\">\n";
	git_print_log($co{'comment'});
	print "</div>\n";

	git_difftree_body(\@difftree, $hash, @$parents);

	git_footer_html();
}

sub git_object {
	# object is defined by:
	# - hash or hash_base alone
	# - hash_base and file_name
	my $type;

	# - hash or hash_base alone
	if ($hash || ($hash_base && !defined $file_name)) {
		my $object_id = $hash || $hash_base;

		open my $fd, "-|", quote_command(
			git_cmd(), 'cat-file', '-t', $object_id) . ' 2> /dev/null'
			or die_error(404, "Object does not exist");
		$type = <$fd>;
		defined $type && chomp $type;
		close $fd
			or die_error(404, "Object does not exist");

	# - hash_base and file_name
	} elsif ($hash_base && defined $file_name) {
		$file_name =~ s,/+$,,;

		system(git_cmd(), "cat-file", '-e', $hash_base) == 0
			or die_error(404, "Base object does not exist");

		# here errors should not happen
		open my $fd, "-|", git_cmd(), "ls-tree", $hash_base, "--", $file_name
			or die_error(500, "Open git-ls-tree failed");
		my $line = <$fd>;
		close $fd;

		#'100644 blob 0fa3f3a66fb6a137f6ec2c19351ed4d807070ffa	panic.c'
		unless ($line && $line =~ m/^([0-9]+) (.+) ([0-9a-fA-F]{40})\t/) {
			die_error(404, "File or directory for given base does not exist");
		}
		$type = $2;
		$hash = $3;
	} else {
		die_error(400, "Not enough information to find object");
	}

	print $cgi->redirect(-uri => href(action=>$type, -full=>1,
	                                  hash=>$hash, hash_base=>$hash_base,
	                                  file_name=>$file_name),
	                     -status => '302 Found');
}

sub git_blobdiff {
	my $format = shift || 'html';
	my $diff_style = $input_params{'diff_style'} || 'inline';

	my $fd;
	my @difftree;
	my %diffinfo;
	my $expires;

	# preparing $fd and %diffinfo for git_patchset_body
	# new style URI
	if (defined $hash_base && defined $hash_parent_base) {
		if (defined $file_name) {
			# read raw output
			open $fd, "-|", git_cmd(), "diff-tree", '-r', @diff_opts,
				$hash_parent_base, $hash_base,
				"--", (defined $file_parent ? $file_parent : ()), $file_name
				or die_error(500, "Open git-diff-tree failed");
			@difftree = map { chomp; $_ } <$fd>;
			close $fd
				or die_error(404, "Reading git-diff-tree failed");
			@difftree
				or die_error(404, "Blob diff not found");

		} elsif (defined $hash &&
		         $hash =~ /[0-9a-fA-F]{40}/) {
			# try to find filename from $hash

			# read filtered raw output
			open $fd, "-|", git_cmd(), "diff-tree", '-r', @diff_opts,
				$hash_parent_base, $hash_base, "--"
				or die_error(500, "Open git-diff-tree failed");
			@difftree =
				# ':100644 100644 03b21826... 3b93d5e7... M	ls-files.c'
				# $hash == to_id
				grep { /^:[0-7]{6} [0-7]{6} [0-9a-fA-F]{40} $hash/ }
				map { chomp; $_ } <$fd>;
			close $fd
				or die_error(404, "Reading git-diff-tree failed");
			@difftree
				or die_error(404, "Blob diff not found");

		} else {
			die_error(400, "Missing one of the blob diff parameters");
		}

		if (@difftree > 1) {
			die_error(400, "Ambiguous blob diff specification");
		}

		%diffinfo = parse_difftree_raw_line($difftree[0]);
		$file_parent ||= $diffinfo{'from_file'} || $file_name;
		$file_name   ||= $diffinfo{'to_file'};

		$hash_parent ||= $diffinfo{'from_id'};
		$hash        ||= $diffinfo{'to_id'};

		# non-textual hash id's can be cached
		if ($hash_base =~ m/^[0-9a-fA-F]{40}$/ &&
		    $hash_parent_base =~ m/^[0-9a-fA-F]{40}$/) {
			$expires = '+1d';
		}

		# open patch output
		open $fd, "-|", git_cmd(), "diff-tree", '-r', @diff_opts,
			'-p', ($format eq 'html' ? "--full-index" : ()),
			$hash_parent_base, $hash_base,
			"--", (defined $file_parent ? $file_parent : ()), $file_name
			or die_error(500, "Open git-diff-tree failed");
	}

	# old/legacy style URI -- not generated anymore since 1.4.3.
	if (!%diffinfo) {
		die_error('404 Not Found', "Missing one of the blob diff parameters")
	}

	# header
	if ($format eq 'html') {
		my $formats_nav =
			$cgi->a({-href => href(action=>"blobdiff_plain", -replay=>1)},
			        "raw");
		$formats_nav .= diff_style_nav($diff_style);
		git_header_html(undef, $expires);
		if (defined $hash_base && (my %co = parse_commit($hash_base))) {
			git_print_page_nav('','', $hash_base,$co{'tree'},$hash_base, $formats_nav);
			git_print_header_div('commit', esc_html($co{'title'}), $hash_base);
		} else {
			print "<div class=\"page_nav\"><br/>$formats_nav<br/></div>\n";
			print "<div class=\"title\">".esc_html("$hash vs $hash_parent")."</div>\n";
		}
		if (defined $file_name) {
			git_print_page_path($file_name, "blob", $hash_base);
		} else {
			print "<div class=\"page_path\"></div>\n";
		}

	} elsif ($format eq 'plain') {
		print $cgi->header(
			-type => 'text/plain',
			-charset => 'utf-8',
			-expires => $expires,
			-content_disposition => 'inline; filename="' . "$file_name" . '.patch"');

		print "X-Git-Url: " . $cgi->self_url() . "\n\n";

	} else {
		die_error(400, "Unknown blobdiff format");
	}

	# patch
	if ($format eq 'html') {
		print "<div class=\"page_body\">\n";

		git_patchset_body($fd, $diff_style,
		                  [ \%diffinfo ], $hash_base, $hash_parent_base);
		close $fd;

		print "</div>\n"; # class="page_body"
		git_footer_html();

	} else {
		while (my $line = <$fd>) {
			$line =~ s!a/($hash|$hash_parent)!'a/'.esc_path($diffinfo{'from_file'})!eg;
			$line =~ s!b/($hash|$hash_parent)!'b/'.esc_path($diffinfo{'to_file'})!eg;

			print $line;

			last if $line =~ m!^\+\+\+!;
		}
		local $/ = undef;
		print <$fd>;
		close $fd;
	}
}

sub git_blobdiff_plain {
	git_blobdiff('plain');
}

# assumes that it is added as later part of already existing navigation,
# so it returns "| foo | bar" rather than just "foo | bar"
sub diff_style_nav {
	my ($diff_style, $is_combined) = @_;
	$diff_style ||= 'inline';

	return "" if ($is_combined);

	my @styles = (inline => 'inline', 'sidebyside' => 'side by side');
	my %styles = @styles;
	@styles =
		@styles[ map { $_ * 2 } 0..$#styles/2 ];

	return join '',
		map { " | ".$_ }
		map {
			$_ eq $diff_style ? $styles{$_} :
			$cgi->a({-href => href(-replay=>1, diff_style => $_)}, $styles{$_})
		} @styles;
}

sub git_commitdiff {
	my %params = @_;
	my $format = $params{-format} || 'html';
	my $diff_style = $input_params{'diff_style'} || 'inline';

	my ($patch_max) = gitweb_get_feature('patches');
	if ($format eq 'patch') {
		die_error(403, "Patch view not allowed") unless $patch_max;
	}

	$hash ||= $hash_base || "HEAD";
	my %co = parse_commit($hash)
	    or die_error(404, "Unknown commit object");

	# choose format for commitdiff for merge
	if (! defined $hash_parent && @{$co{'parents'}} > 1) {
		$hash_parent = '--cc';
	}
	# we need to prepare $formats_nav before almost any parameter munging
	my $formats_nav;
	if ($format eq 'html') {
		$formats_nav =
			$cgi->a({-href => href(action=>"commitdiff_plain", -replay=>1)},
			        "raw");
		if ($patch_max && @{$co{'parents'}} <= 1) {
			$formats_nav .= " | " .
				$cgi->a({-href => href(action=>"patch", -replay=>1)},
					"patch");
		}
		$formats_nav .= diff_style_nav($diff_style, @{$co{'parents'}} > 1);

		if (defined $hash_parent &&
		    $hash_parent ne '-c' && $hash_parent ne '--cc') {
			# commitdiff with two commits given
			my $hash_parent_short = $hash_parent;
			if ($hash_parent =~ m/^[0-9a-fA-F]{40}$/) {
				$hash_parent_short = substr($hash_parent, 0, 7);
			}
			$formats_nav .=
				' (from';
			for (my $i = 0; $i < @{$co{'parents'}}; $i++) {
				if ($co{'parents'}[$i] eq $hash_parent) {
					$formats_nav .= ' parent ' . ($i+1);
					last;
				}
			}
			$formats_nav .= ': ' .
				$cgi->a({-href => href(-replay=>1,
				                       hash=>$hash_parent, hash_base=>undef)},
				        esc_html($hash_parent_short)) .
				')';
		} elsif (!$co{'parent'}) {
			# --root commitdiff
			$formats_nav .= ' (initial)';
		} elsif (scalar @{$co{'parents'}} == 1) {
			# single parent commit
			$formats_nav .=
				' (parent: ' .
				$cgi->a({-href => href(-replay=>1,
				                       hash=>$co{'parent'}, hash_base=>undef)},
				        esc_html(substr($co{'parent'}, 0, 7))) .
				')';
		} else {
			# merge commit
			if ($hash_parent eq '--cc') {
				$formats_nav .= ' | ' .
					$cgi->a({-href => href(-replay=>1,
					                       hash=>$hash, hash_parent=>'-c')},
					        'combined');
			} else { # $hash_parent eq '-c'
				$formats_nav .= ' | ' .
					$cgi->a({-href => href(-replay=>1,
					                       hash=>$hash, hash_parent=>'--cc')},
					        'compact');
			}
			$formats_nav .=
				' (merge: ' .
				join(' ', map {
					$cgi->a({-href => href(-replay=>1,
					                       hash=>$_, hash_base=>undef)},
					        esc_html(substr($_, 0, 7)));
				} @{$co{'parents'}} ) .
				')';
		}
	}

	my $hash_parent_param = $hash_parent;
	if (!defined $hash_parent_param) {
		# --cc for multiple parents, --root for parentless
		$hash_parent_param =
			@{$co{'parents'}} > 1 ? '--cc' : $co{'parent'} || '--root';
	}

	# read commitdiff
	my $fd;
	my @difftree;
	if ($format eq 'html') {
		open $fd, "-|", git_cmd(), "diff-tree", '-r', @diff_opts,
			"--no-commit-id", "--patch-with-raw", "--full-index",
			$hash_parent_param, $hash, "--"
			or die_error(500, "Open git-diff-tree failed");

		while (my $line = <$fd>) {
			chomp $line;
			# empty line ends raw part of diff-tree output
			last unless $line;
			push @difftree, scalar parse_difftree_raw_line($line);
		}

	} elsif ($format eq 'plain') {
		open $fd, "-|", git_cmd(), "diff-tree", '-r', @diff_opts,
			'-p', $hash_parent_param, $hash, "--"
			or die_error(500, "Open git-diff-tree failed");
	} elsif ($format eq 'patch') {
		# For commit ranges, we limit the output to the number of
		# patches specified in the 'patches' feature.
		# For single commits, we limit the output to a single patch,
		# diverging from the git-format-patch default.
		my @commit_spec = ();
		if ($hash_parent) {
			if ($patch_max > 0) {
				push @commit_spec, "-$patch_max";
			}
			push @commit_spec, '-n', "$hash_parent..$hash";
		} else {
			if ($params{-single}) {
				push @commit_spec, '-1';
			} else {
				if ($patch_max > 0) {
					push @commit_spec, "-$patch_max";
				}
				push @commit_spec, "-n";
			}
			push @commit_spec, '--root', $hash;
		}
		open $fd, "-|", git_cmd(), "format-patch", @diff_opts,
			'--encoding=utf8', '--stdout', @commit_spec
			or die_error(500, "Open git-format-patch failed");
	} else {
		die_error(400, "Unknown commitdiff format");
	}

	# non-textual hash id's can be cached
	my $expires;
	if ($hash =~ m/^[0-9a-fA-F]{40}$/) {
		$expires = "+1d";
	}

	# write commit message
	if ($format eq 'html') {
		my $refs = git_get_references();
		my $ref = format_ref_marker($refs, $co{'id'});

		git_header_html(undef, $expires);
		git_print_page_nav('commitdiff','', $hash,$co{'tree'},$hash, $formats_nav);
		git_print_header_div('commit', esc_html($co{'title'}) . $ref, $hash);
		print "<div class=\"title_text\">\n" .
		      "<table class=\"object_header\">\n";
		git_print_authorship_rows(\%co);
		print "</table>".
		      "</div>\n";
		print "<div class=\"page_body\">\n";
		if (@{$co{'comment'}} > 1) {
			print "<div class=\"log\">\n";
			git_print_log($co{'comment'}, -final_empty_line=> 1, -remove_title => 1);
			print "</div>\n"; # class="log"
		}

	} elsif ($format eq 'plain') {
		my $refs = git_get_references("tags");
		my $tagname = git_get_rev_name_tags($hash);
		my $filename = basename($project) . "-$hash.patch";

		print $cgi->header(
			-type => 'text/plain',
			-charset => 'utf-8',
			-expires => $expires,
			-content_disposition => 'inline; filename="' . "$filename" . '"');
		my %ad = parse_date($co{'author_epoch'}, $co{'author_tz'});
		print "From: " . to_utf8($co{'author'}) . "\n";
		print "Date: $ad{'rfc2822'} ($ad{'tz_local'})\n";
		print "Subject: " . to_utf8($co{'title'}) . "\n";

		print "X-Git-Tag: $tagname\n" if $tagname;
		print "X-Git-Url: " . $cgi->self_url() . "\n\n";

		foreach my $line (@{$co{'comment'}}) {
			print to_utf8($line) . "\n";
		}
		print "---\n\n";
	} elsif ($format eq 'patch') {
		my $filename = basename($project) . "-$hash.patch";

		print $cgi->header(
			-type => 'text/plain',
			-charset => 'utf-8',
			-expires => $expires,
			-content_disposition => 'inline; filename="' . "$filename" . '"');
	}

	# write patch
	if ($format eq 'html') {
		my $use_parents = !defined $hash_parent ||
			$hash_parent eq '-c' || $hash_parent eq '--cc';
		git_difftree_body(\@difftree, $hash,
		                  $use_parents ? @{$co{'parents'}} : $hash_parent);
		print "<br/>\n";

		git_patchset_body($fd, $diff_style,
		                  \@difftree, $hash,
		                  $use_parents ? @{$co{'parents'}} : $hash_parent);
		close $fd;
		print "</div>\n"; # class="page_body"
		git_footer_html();

	} elsif ($format eq 'plain') {
		local $/ = undef;
		print <$fd>;
		close $fd
			or print "Reading git-diff-tree failed\n";
	} elsif ($format eq 'patch') {
		local $/ = undef;
		print <$fd>;
		close $fd
			or print "Reading git-format-patch failed\n";
	}
}

sub git_commitdiff_plain {
	git_commitdiff(-format => 'plain');
}

# format-patch-style patches
sub git_patch {
	git_commitdiff(-format => 'patch', -single => 1);
}

sub git_patches {
	git_commitdiff(-format => 'patch');
}

sub git_history {
	git_log_generic('history', \&git_history_body,
	                $hash_base, $hash_parent_base,
	                $file_name, $hash);
}

sub git_search {
	$searchtype ||= 'commit';

	# check if appropriate features are enabled
	gitweb_check_feature('search')
		or die_error(403, "Search is disabled");
	if ($searchtype eq 'pickaxe') {
		# pickaxe may take all resources of your box and run for several minutes
		# with every query - so decide by yourself how public you make this feature
		gitweb_check_feature('pickaxe')
			or die_error(403, "Pickaxe search is disabled");
	}
	if ($searchtype eq 'grep') {
		# grep search might be potentially CPU-intensive, too
		gitweb_check_feature('grep')
			or die_error(403, "Grep search is disabled");
	}

	if (!defined $searchtext) {
		die_error(400, "Text field is empty");
	}
	if (!defined $hash) {
		$hash = git_get_head_hash($project);
	}
	my %co = parse_commit($hash);
	if (!%co) {
		die_error(404, "Unknown commit object");
	}
	if (!defined $page) {
		$page = 0;
	}

	if ($searchtype eq 'commit' ||
	    $searchtype eq 'author' ||
	    $searchtype eq 'committer') {
		git_search_message(%co);
	} elsif ($searchtype eq 'pickaxe') {
		git_search_changes(%co);
	} elsif ($searchtype eq 'grep') {
		git_search_files(%co);
	} e