#!/usr/bin/perl

# gitweb.pl - simple web interface to track changes in git repositories
#
# (C) 2005, Kay Sievers <kay.sievers@vrfy.org>
# (C) 2005, Christian Gierke <ch@gierke.de>
#
# This program is licensed under the GPL v2, or a later version

use strict;
use warnings;
use CGI qw(:standard :escapeHTML);
use CGI::Util qw(unescape);
use CGI::Carp qw(fatalsToBrowser);
use Fcntl ':mode';

my $cgi = new CGI;
my $version =           "149";
my $my_url =            $cgi->url();
my $my_uri =            $cgi->url(-absolute => 1);
my $rss_link = "";

# absolute fs-path which will be prepended to the project path
my $projectroot =       "/pub/scm";

# location of the git-core binaries
my $gitbin =            "/usr/bin";

# location for temporary files needed for diffs
my $gittmp =            "/tmp/gitweb";

# target of the home link on top of all pages
my $home_link =         $my_uri;

# html text to include at home page
my $home_text =         "indextext.html";

# source of projects list
#my $projects_list = $projectroot;
my $projects_list = "index/index.aux";

# input validation and dispatch
my $action = $cgi->param('a');
if (defined $action) {
        if ($action =~ m/[^0-9a-zA-Z\.\-]+/) {
                undef $action;
                die_error(undef, "Invalid action parameter.");
        }
        if ($action eq "git-logo.png") {
                git_logo();
                exit;
        }
} else {
        $action = "summary";
}

my $project = $cgi->param('p');
if (defined $project) {
        if ($project =~ m/(^|\/)(|\.|\.\.)($|\/)/) {
                undef $project;
                die_error(undef, "Non-canonical project parameter.");
        }
        if ($project =~ m/[^a-zA-Z0-9_\.\/\-\+\#\~]/) {
                undef $project;
                die_error(undef, "Invalid character in project parameter.");
        }
        if (!(-d "$projectroot/$project")) {
                undef $project;
                die_error(undef, "No such directory.");
        }
        if (!(-e "$projectroot/$project/HEAD")) {
                undef $project;
                die_error(undef, "No such project.");
        }
        $rss_link = "<link rel=\"alternate\" title=\"$project log\" href=\"$my_uri?p=$project;a=rss\" type=\"application/rss+xml\"/>";
        $ENV{'GIT_OBJECT_DIRECTORY'} = "$projectroot/$project/objects";
        $ENV{'SHA1_FILE_DIRECTORY'} = "$projectroot/$project/objects";
} else {
        git_project_list();
        exit;
}

my $file_name = $cgi->param('f');
if (defined $file_name) {
        if ($file_name =~ m/(^|\/)(|\.|\.\.)($|\/)/) {
                undef $file_name;
                die_error(undef, "Non-canonical file parameter.");
        }
        if ($file_name =~ m/[^a-zA-Z0-9_\.\/\-\+\#\~\:\!]/) {
                undef $file_name;
                die_error(undef, "Invalid character in file parameter.");
        }
}

my $hash = $cgi->param('h');
if (defined $hash && !($hash =~ m/^[0-9a-fA-F]{40}$/)) {
        undef $hash;
        die_error(undef, "Invalid hash parameter.");
}

my $hash_parent = $cgi->param('hp');
if (defined $hash_parent && !($hash_parent =~ m/^[0-9a-fA-F]{40}$/)) {
        undef $hash_parent;
        die_error(undef, "Invalid hash_parent parameter.");
}

my $hash_base = $cgi->param('hb');
if (defined $hash_base && !($hash_base =~ m/^[0-9a-fA-F]{40}$/)) {
        undef $hash_base;
        die_error(undef, "Invalid parent hash parameter.");
}

my $time_back = $cgi->param('t');
if (defined $time_back) {
        if ($time_back =~ m/^[^0-9]+$/) {
                undef $time_back;
                die_error(undef, "Invalid time parameter.");
        }
}

if ($action eq "summary") {
        git_summary();
        exit;
} elsif ($action eq "tags") {
        git_tags();
        exit;
} elsif ($action eq "blob") {
        git_blob();
        exit;
} elsif ($action eq "tree") {
        git_tree();
        exit;
} elsif ($action eq "rss") {
        git_rss();
        exit;
} elsif ($action eq "commit") {
        git_commit();
        exit;
} elsif ($action eq "log") {
        git_log();
        exit;
} elsif ($action eq "blobdiff") {
        git_blobdiff();
        exit;
} elsif ($action eq "commitdiff") {
        git_commitdiff();
        exit;
} elsif ($action eq "history") {
        git_history();
        exit;
} else {
        undef $action;
        die_error(undef, "Unknown action.");
        exit;
}

sub git_header_html {
        my $status = shift || "200 OK";

        my $title = "git";
        if (defined $project) {
                $title .= " - $project";
                if (defined $action) {
                        $title .= "/$action";
                }
        }
        print $cgi->header(-type=>'text/html',  -charset => 'utf-8', -status=> $status);
        print <<EOF;
<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en-US" lang="en-US">
<!-- git web interface v$version, (C) 2005, Kay Sievers <kay.sievers\@vrfy.org>, Christian Gierke <ch\@gierke.de> -->
<head>
<title>$title</title>
$rss_link
<style type="text/css">
body { font-family: sans-serif; font-size: 12px; margin:0px; border:solid #d9d8d1; border-width:1px; margin:10px; }
a { color:#0000cc; }
a:hover, a:visited, a:active { color:#880000; }
div.page_header { height:25px; padding:8px; font-size:18px; font-weight:bold; background-color:#d9d8d1; }
div.page_header a:visited { color:#0000cc; }
div.page_header a:hover { color:#880000; }
div.page_nav { padding:8px; }
div.page_nav a:visited { color:#0000cc; }
div.page_path { font-weight:bold; padding:8px; border:solid #d9d8d1; border-width:0px 0px 1px}
div.page_footer { height:17px; padding:4px 8px; background-color: #d9d8d1; }
div.page_footer_text { float:left; color:#555555; font-style:italic; }
div.page_body { padding:8px; }
div.title, a.title {
        display:block; padding:6px 8px;
        font-weight:bold; background-color:#edece6; text-decoration:none; color:#000000;
}
a.title:hover { background-color: #d9d8d1; }
div.title_text { padding:6px 8px; border: solid #d9d8d1; border-width:0px 0px 1px; }
div.log_body { padding:8px 8px 8px 150px; }
span.age { position:relative; float:left; width:142px; font-style:italic; }
div.log_link {
        font-size:10px; font-family:sans-serif; font-style:normal;
        position:relative; float:left; width:142px;
}
div.list { display:block; padding:4px 8px 2px; }
div.list_head {
        display:block; padding:6px 6px 4px; border:solid #d9d8d1;
        border-width:0px 0px 1px; font-style:italic;
}
div.list a { text-decoration:none; color:#000000; }
div.list a:hover { color:#880000; }
div.list_link {
        padding:4px 8px 6px; border:solid #d9d8d1; border-width:0px 0px 1px;
        font-family:sans-serif; font-size:10px;
}
td { padding:5px 15px 0px 0px; font-size:12px; }
th { padding-right:10px; font-size:12px; text-align:left; }
td.link { font-family:sans-serif; font-size:10px; }
td.pre { font-family:monospace; font-size:12px; white-space:pre; padding:2px 15px 0px 0px; }
div.pre { font-family:monospace; font-size:12px; white-space:pre; }
div.diff_info { font-family:monospace; color:#000099; background-color:#edece6; font-style:italic; }
div.index_include { border:solid #d9d8d1; border-width:0px 0px 1px; padding:12px 8px; }
a.rss_logo { float:right; padding:3px 0px; width:35px; line-height:10px;
        border:1px solid; border-color:#fcc7a5 #7d3302 #3e1a01 #ff954e;
        color:#ffffff; background-color:#ff6600;
        font-weight:bold; font-family:sans-serif; font-size:10px;
        text-align:center; text-decoration:none;
}
a.rss_logo:hover { background-color:#ee5500; }
</style>
</head>
<body>
EOF
        print "<div class=\"page_header\">\n" .
              "<a href=\"http://kernel.org/pub/software/scm/git/docs/\">" .
              "<img src=\"$my_uri?a=git-logo.png\" width=\"72\" height=\"27\" alt=\"git\" style=\"float:right; border-width:0px;\"/></a>";
        print $cgi->a({-href => $home_link}, "projects") . " / ";
        if (defined $project) {
                print $cgi->a({-href => "$my_uri?p=$project;a=summary"}, escapeHTML($project));
                if (defined $action) {
                        print " / $action";
                }
        }
        print "</div>\n";
}

sub git_footer_html {
        print "<div class=\"page_footer\">\n";
        if (defined $project) {
                my $descr = git_read_description($project);
                if (defined $descr) {
                        print "<div class=\"page_footer_text\">" . escapeHTML($descr) . "</div>\n";
                }
                print $cgi->a({-href => "$my_uri?p=$project;a=rss", -class => "rss_logo"}, "RSS") . "\n";
        }
        print "</div>\n" .
              "</body>\n" .
              "</html>";
}

sub die_error {
        my $status = shift || "403 Forbidden";
        my $error = shift || "Malformed query, file missing or permission denied"; 

        git_header_html($status);
        print "<div class=\"page_body\">\n" .
              "<br/><br/>\n";
        print "$status - $error\n";
        print "<br/></div>\n";
        git_footer_html();
        exit;
}

sub git_get_type {
        my $hash = shift;

        open my $fd, "-|", "$gitbin/git-cat-file -t $hash" || return;
        my $type = <$fd>;
        close $fd;
        chomp $type;
        return $type;
}

sub git_read_hash {
        my $path = shift;

        open my $fd, "$projectroot/$path" || return undef;
        my $head = <$fd>;
        close $fd;
        chomp $head;
        if ($head =~ m/^[0-9a-fA-F]{40}$/) {
                return $head;
        }
}

sub git_read_description {
        my $path = shift;

        open my $fd, "$projectroot/$path/description" || return undef;
        my $descr = <$fd>;
        close $fd;
        chomp $descr;
        return $descr;
}

sub git_read_tag {
        my $tag_id = shift;
        my %tag;

        open my $fd, "-|", "$gitbin/git-cat-file tag $tag_id" || return;
        while (my $line = <$fd>) {
                chomp $line;
                if ($line =~ m/^object ([0-9a-fA-F]{40})$/) {
                        $tag{'object'} = $1;
                } elsif ($line =~ m/^type (.*)$/) {
                        $tag{'type'} = $1;
                } elsif ($line =~ m/^tag (.*)$/) {
                        $tag{'name'} = $1;
                }
        }
        close $fd || return;
        if (!defined $tag{'name'}) {
                return
        };
        return %tag
}

sub git_read_commit {
        my $commit = shift;
        my %co;
        my @parents;

        open my $fd, "-|", "$gitbin/git-cat-file commit $commit" || return;
        while (my $line = <$fd>) {
                last if $line eq "\n";
                chomp $line;
                if ($line =~ m/^tree (.*)$/) {
                        $co{'tree'} = $1;
                } elsif ($line =~ m/^parent (.*)$/) {
                        push @parents, $1;
                } elsif ($line =~ m/^author (.*) ([0-9]+) (.*)$/) {
                        $co{'author'} = $1;
                        $co{'author_epoch'} = $2;
                        $co{'author_tz'} = $3;
                        $co{'author_name'} = $co{'author'};
                        $co{'author_name'} =~ s/ <.*//;
                } elsif ($line =~ m/^committer (.*) ([0-9]+) (.*)$/) {
                        $co{'committer'} = $1;
                        $co{'committer_epoch'} = $2;
                        $co{'committer_tz'} = $3;
                        $co{'committer_name'} = $co{'committer'};
                        $co{'committer_name'} =~ s/ <.*//;
                }
        }
        if (!defined $co{'tree'}) {
                close $fd;
                return undef
        };
        $co{'parents'} = \@parents;
        $co{'parent'} = $parents[0];
        my (@comment) = map { chomp; $_ } <$fd>;
        $co{'comment'} = \@comment;
        $comment[0] =~ m/^(.{0,60}[^ ]*)/;
        $co{'title'} = $1;
        if ($comment[0] ne $co{'title'}) {
                $co{'title'} .= " ...";
        }
        close $fd || return;

        my $age = time - $co{'committer_epoch'};
        $co{'age'} = $age;
        if ($age > 60*60*24*365*2) {
                $co{'age_string'} = (int $age/60/60/24/365);
                $co{'age_string'} .= " years ago";
        } elsif ($age > 60*60*24*(365/12)*2) {
                $co{'age_string'} = int $age/60/60/24/(365/12);
                $co{'age_string'} .= " months ago";
        } elsif ($age > 60*60*24*7*2) {
                $co{'age_string'} = int $age/60/60/24/7;
                $co{'age_string'} .= " weeks ago";
        } elsif ($age > 60*60*24*2) {
                $co{'age_string'} = int $age/60/60/24;
                $co{'age_string'} .= " days ago";
        } elsif ($age > 60*60*2) {
                $co{'age_string'} = int $age/60/60;
                $co{'age_string'} .= " hours ago";
        } elsif ($age > 60*2) {
                $co{'age_string'} = int $age/60;
                $co{'age_string'} .= " minutes ago";
        } elsif ($age > 2) {
                $co{'age_string'} = int $age;
                $co{'age_string'} .= " seconds ago";
        } else {
                $co{'age_string'} .= " right now";
        }
        return %co;
}

sub git_diff_html {
        my $from = shift;
        my $from_name = shift;
        my $to = shift;
        my $to_name = shift;

        my $from_tmp = "/dev/null";
        my $to_tmp = "/dev/null";
        my $pid = $$;

        # create tmp from-file
        if (defined $from) {
                $from_tmp = "$gittmp/gitweb_" . $$ . "_from";
                open my $fd2, "> $from_tmp";
                open my $fd, "-|", "$gitbin/git-cat-file blob $from";
                my @file = <$fd>;
                print $fd2 @file;
                close $fd2;
                close $fd;
        }

        # create tmp to-file
        if (defined $to) {
                $to_tmp = "$gittmp/gitweb_" . $$ . "_to";
                open my $fd2, "> $to_tmp";
                open my $fd, "-|", "$gitbin/git-cat-file blob $to";
                my @file = <$fd>;
                print $fd2 @file;
                close $fd2;
                close $fd;
        }

        open my $fd, "-|", "/usr/bin/diff -u -p -L $from_name -L $to_name $from_tmp $to_tmp";
        while (my $line = <$fd>) {
                chomp($line);
                my $char = substr($line, 0, 1);
                my $color = "";
                if ($char eq '+') {
                        $color = " style=\"color:#008800;\"";
                } elsif ($char eq '-') {
                        $color = " style=\"color:#cc0000;\"";
                } elsif ($char eq '@') {
                        $color = " style=\"color:#990099;\"";
                } elsif ($char eq '\\') {
                        # skip errors
                        next;
                }
                print "<div class=\"pre\"$color>" . escapeHTML($line) . "</div>\n";
        }
        close $fd;

        if (defined $from) {
                unlink($from_tmp);
        }
        if (defined $to) {
                unlink($to_tmp);
        }
}

sub mode_str {
        my $mode = oct shift;

        if (S_ISDIR($mode & S_IFMT)) {
                return 'drwxr-xr-x';
        } elsif (S_ISLNK($mode)) {
                return 'lrwxrwxrwx';
        } elsif (S_ISREG($mode)) {
                # git cares only about the executable bit
                if ($mode & S_IXUSR) {
                        return '-rwxr-xr-x';
                } else {
                        return '-rw-r--r--';
                };
        } else {
                return '----------';
        }
}

sub file_type {
        my $mode = oct shift;

        if (S_ISDIR($mode & S_IFMT)) {
                return "directory";
        } elsif (S_ISLNK($mode)) {
                return "symlink";
        } elsif (S_ISREG($mode)) {
                return "file";
        } else {
                return "unknown";
        }
}

sub date_str {
        my $epoch = shift;
        my $tz = shift || "-0000";

        my %date;
        my @months = ("Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec");
        my @days = ("Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat");
        my ($sec, $min, $hour, $mday, $mon, $year, $wday, $yday) = gmtime($epoch);
        $date{'hour'} = $hour;
        $date{'minute'} = $min;
        $date{'mday'} = $mday;
        $date{'day'} = $days[$wday];
        $date{'month'} = $months[$mon];
        $date{'rfc2822'} = sprintf "%s, %d %s %4d %02d:%02d:%02d +0000", $days[$wday], $mday, $months[$mon], 1900+$year, $hour ,$min, $sec;
        $date{'mday-time'} = sprintf "%d %s %02d:%02d", $mday, $months[$mon], $hour ,$min;

        $tz =~ m/^([+\-][0-9][0-9])([0-9][0-9])$/;
        my $local = $epoch + ((int $1 + ($2/60)) * 3600);
        ($sec, $min, $hour, $mday, $mon, $year, $wday, $yday) = gmtime($local);
        $date{'hour_local'} = $hour;
        $date{'minute_local'} = $min;
        $date{'tz_local'} = $tz;
        return %date;
}

# git-logo (cached in browser for one day)
sub git_logo {
        print $cgi->header(-type => 'image/png', -expires => '+1d');
        # cat git-logo.png | hexdump -e '16/1 " %02x"  "\n"' | sed 's/ /\\x/g'
        print   "\x89\x50\x4e\x47\x0d\x0a\x1a\x0a\x00\x00\x00\x0d\x49\x48\x44\x52" .
                "\x00\x00\x00\x48\x00\x00\x00\x1b\x04\x03\x00\x00\x00\x2d\xd9\xd4" .
                "\x2d\x00\x00\x00\x18\x50\x4c\x54\x45\xff\xff\xff\x60\x60\x5d\xb0" .
                "\xaf\xaa\x00\x80\x00\xce\xcd\xc7\xc0\x00\x00\xe8\xe8\xe6\xf7\xf7" .
                "\xf6\x95\x0c\xa7\x47\x00\x00\x00\x73\x49\x44\x41\x54\x28\xcf\x63" .
                "\x48\x67\x20\x04\x4a\x5c\x18\x0a\x08\x2a\x62\x53\x61\x20\x02\x08" .
                "\x0d\x69\x45\xac\xa1\xa1\x01\x30\x0c\x93\x60\x36\x26\x52\x91\xb1" .
                "\x01\x11\xd6\xe1\x55\x64\x6c\x6c\xcc\x6c\x6c\x0c\xa2\x0c\x70\x2a" .
                "\x62\x06\x2a\xc1\x62\x1d\xb3\x01\x02\x53\xa4\x08\xe8\x00\x03\x18" .
                "\x26\x56\x11\xd4\xe1\x20\x97\x1b\xe0\xb4\x0e\x35\x24\x71\x29\x82" .
                "\x99\x30\xb8\x93\x0a\x11\xb9\x45\x88\xc1\x8d\xa0\xa2\x44\x21\x06" .
                "\x27\x41\x82\x40\x85\xc1\x45\x89\x20\x70\x01\x00\xa4\x3d\x21\xc5" .
                "\x12\x1c\x9a\xfe\x00\x00\x00\x00\x49\x45\x4e\x44\xae\x42\x60\x82";
}

sub get_file_owner {
        my $path = shift;

        my ($dev, $ino, $mode, $nlink, $st_uid, $st_gid, $rdev, $size) = stat($path);
        my ($name, $passwd, $uid, $gid, $quota, $comment, $gcos, $dir, $shell) = getpwuid($st_uid);
        if (!defined $gcos) {
                return undef;
        }
        my $owner = $gcos;
        $owner =~ s/[,;].*$//;
        return $owner;
}

sub git_project_list {
        my @list;

        if (-d $projects_list) {
                # search in directory
                my $dir = $projects_list;
                opendir my $dh, $dir || return undef;
                while (my $dir = readdir($dh)) {
                        if (-e "$projectroot/$dir/HEAD") {
                                my $pr = {
                                        path => $dir,
                                };
                                push @list, $pr
                        }
                }
                closedir($dh);
        } elsif (-f $projects_list) {
                # read from file:
                # 'git/git.git:Linus Torvalds'
                # 'linux/hotplug/udev.git'
                open my $fd , $projects_list || return undef;
                while (my $line = <$fd>) {
                        chomp $line;
                        my ($path, $owner) = split ' ', $line;
                        $path = unescape($path);
                        $owner = unescape($owner);
                        if (!defined $path) {
                                next;
                        }
                        if (-e "$projectroot/$path/HEAD") {
                                my $pr = {
                                        path => $path,
                                        owner => $owner,
                                };
                                push @list, $pr
                        }
                }
                close $fd;
        }

        if (!@list) {
                die_error(undef, "No project found.");
        }
        @list = sort {$a->{'path'} cmp $b->{'path'}} @list;

        git_header_html();
        if (-f $home_text) {
                print "<div class=\"index_include\">\n";
                open (my $fd, $home_text);
                print <$fd>;
                close $fd;
                print "</div>\n";
        }
        print "<div class=\"page_body\"><br/>\n" .
              "<table cellspacing=\"0\">\n" .
              "<tr>\n" .
              "<th>Project</th>\n" .
              "<th>Description</th>\n" .
              "<th>Owner</th>\n" .
              "<th>last change</th>\n" .
              "<th></th>\n" .
              "</tr>\n";
        foreach my $pr (@list) {
                my %proj = %$pr;
                my $head = git_read_hash("$proj{'path'}/HEAD");
                if (!defined $head) {
                        next;
                }
                $ENV{'GIT_OBJECT_DIRECTORY'} = "$projectroot/$proj{'path'}/objects";
                $ENV{'SHA1_FILE_DIRECTORY'} = "$projectroot/$proj{'path'}/objects";
                my %co = git_read_commit($head);
                if (!%co) {
                        next;
                }
                my $descr = git_read_description($proj{'path'}) || "";
                # get directory owner if not already specified
                if (!defined $proj{'owner'}) {
                        $proj{'owner'} = get_file_owner("$projectroot/$proj{'path'}") || "";
                }
                print "<tr>\n" .
                      "<td>" . $cgi->a({-href => "$my_uri?p=$proj{'path'};a=summary"}, escapeHTML($proj{'path'})) . "</td>\n" .
                      "<td>$descr</td>\n" .
                      "<td><i>$proj{'owner'}</i></td>\n";
                my $colored_age;
                if ($co{'age'} < 60*60*2) {
                        $colored_age = "<span style =\"color: #009900;\"><b><i>$co{'age_string'}</i></b></span>";
                } elsif ($co{'age'} < 60*60*24*2) {
                        $colored_age = "<span style =\"color: #009900;\"><i>$co{'age_string'}</i></span>";
                } else {
                        $colored_age = "<i>$co{'age_string'}</i>";
                }
                print "<td>$colored_age</td>\n" .
                      "<td class=\"link\">" .
                      $cgi->a({-href => "$my_uri?p=$proj{'path'};a=summary"}, "summary") .
                      " | " . $cgi->a({-href => "$my_uri?p=$proj{'path'};a=log"}, "log") .
                      " | " . $cgi->a({-href => "$my_uri?p=$proj{'path'};a=tree"}, "tree") .
                      "</td>\n" .
                      "</tr>\n";
        }
        print "</table>\n" .
              "<br/>\n" .
              "</div>\n";
        git_footer_html();
}

sub git_read_tags {
        my @taglist;

        opendir my $dh, "$projectroot/$project/refs/tags";
        my @tags = grep !m/^\./, readdir $dh;
        closedir($dh);
        foreach my $tag_file (@tags) {
                my $tag_id = git_read_hash("$project/refs/tags/$tag_file");
                my $type = git_get_type($tag_id) || next;
                my %tag_item;
                my %co;
                if ($type eq "tag") {
                        my %tag = git_read_tag($tag_id);
                        if ($tag{'type'} eq "commit") {
                                %co = git_read_commit($tag{'object'});
                        }
                        $tag_item{'type'} = $tag{'type'};
                        $tag_item{'name'} = $tag{'name'};
                        $tag_item{'id'} = $tag{'object'};
                } elsif ($type eq "commit"){
                        %co = git_read_commit($tag_id);
                        $tag_item{'type'} = "commit";
                        $tag_item{'name'} = $tag_file;
                        $tag_item{'id'} = $tag_id;
                }
                $tag_item{'epoch'} = $co{'author_epoch'} || 0;
                $tag_item{'age'} = $co{'age_string'} || "unknown";

                push @taglist, \%tag_item;
        }
        # sort tags by age
        @taglist = sort {$b->{'epoch'} <=> $a->{'epoch'}} @taglist;
        return \@taglist;
}

sub git_summary {
        my $descr = git_read_description($project) || "none";
        my $head = git_read_hash("$project/HEAD");
        $ENV{'GIT_OBJECT_DIRECTORY'} = "$projectroot/$project/objects";
        $ENV{'SHA1_FILE_DIRECTORY'} = "$projectroot/$project/objects";
        my %co = git_read_commit($head);
        my %cd = date_str($co{'committer_epoch'}, $co{'committer_tz'});

        my $owner;
        if (-f $projects_list) {
                open (my $fd , $projects_list);
                while (my $line = <$fd>) {
                        chomp $line;
                        my ($pr, $ow) = split ' ', $line;
                        $pr = unescape($pr);
                        $ow = unescape($ow);
                        if ($pr eq $project) {
                                $owner = $ow;
                                last;
                        }
                }
                close $fd;
        }
        if (!defined $owner) {
                $owner = get_file_owner("$projectroot/$project");
        }

        git_header_html();
        print "<div class=\"page_nav\">\n" .
              $cgi->a({-href => "$my_uri?p=$project;a=log"}, "log") .
              " | " . $cgi->a({-href => "$my_uri?p=$project;a=tree"}, "tree") .
              "<br/><br/>\n" .
              "</div>\n";
        print "<div class=\"title\">project</div>\n";
        print "<div class=\"page_body\">\n" .
              "<table cellspacing=\"0\">\n" .
              "<tr><td>description</td><td>" . escapeHTML($descr) . "</td></tr>\n" .
              "<tr><td>owner</td><td>$owner</td></tr>\n" .
              "<tr><td>last change</td><td>$cd{'rfc2822'}</td></tr>\n" .
              "</table>\n" .
              "<br/></div>\n";
        open my $fd, "-|", "$gitbin/git-rev-list --max-count=11 " . git_read_hash("$project/HEAD") || die_error(undef, "Open failed.");
        my (@revlist) = map { chomp; $_ } <$fd>;
        close $fd;
        print "<div>\n" .
              $cgi->a({-href => "$my_uri?p=$project;a=log", -class => "title"}, "recent commits") .
              "</div>\n";
        my $i = 10;
        print  "<div class=\"page_body\">\n" .
               "<table cellspacing=\"0\">\n";
        foreach my $commit (@revlist) {
                my %co = git_read_commit($commit);
                my %ad = date_str($co{'author_epoch'});
                print "<tr>\n";
                if (--$i > 0) {
                        print "<td>$co{'age_string'}</td>\n" .
                              "<td>$co{'author_name'}</td>\n" .
                              "<td>" . $cgi->a({-href => "$my_uri?p=$project;a=commit;h=$commit"}, escapeHTML($co{'title'})) . "</td>\n" .
                              "</tr>";
                } else {
                        print "<td>" . $cgi->a({-href => "$my_uri?p=$project;a=log"}, "...") . "</td>\n" .
                        "</tr>";
                        last;
                }
        }
        print "</table\n>" .
              "</div>\n";

        my $taglist = git_read_tags();
        if (defined @$taglist) {
                print "<div>\n" .
                      $cgi->a({-href => "$my_uri?p=$project;a=tags", -class => "title"}, "recent tags") .
                      "</div>\n";
                my $i = 10;
                print  "<div class=\"page_body\">\n" .
                       "<table cellspacing=\"0\">\n";
                foreach my $entry (@$taglist) {
                        my %tag = %$entry;
                        print "<tr>\n";
                        if (--$i > 0) {
                                print "<td>$tag{'age'}</td>\n" .
                                      "<td>" . $cgi->a({-href => "$my_uri?p=$project;a=$tag{'type'};h=$tag{'id'}"}, escapeHTML($tag{'name'})) . "</td>\n" .
                                      "</tr>";
                        } else {
                                print "<td>" . $cgi->a({-href => "$my_uri?p=$project;a=tags"}, "...") . "</td>\n" .
                                "</tr>";
                                last;
                        }
                }
                print "</table\n>" .
                      "</div>\n";
        }
        git_footer_html();
}

sub git_tags {
        my $head = git_read_hash("$project/HEAD");
        git_header_html();
        print "<div class=\"page_nav\">\n" .
              $cgi->a({-href => "$my_uri?p=$project;a=log"}, "log") .
              " | " . $cgi->a({-href => "$my_uri?p=$project;a=commit;h=$head"}, "commit") .
              " | " . $cgi->a({-href => "$my_uri?p=$project;a=tree"}, "tree") .
              "<br/><br/>\n" .
              "</div>\n";
        my $taglist = git_read_tags();
        print "<div>\n" .
              $cgi->a({-href => "$my_uri?p=$project;a=summary", -class => "title"}, "tags") .
              "</div>\n";
        if (defined @$taglist) {
                foreach my $entry (@$taglist) {
                        my %tag = %$entry;
                        print "<div class=\"list\">\n" .
                              $cgi->a({-href => "$my_uri?p=$project;a=$tag{'type'};h=$tag{'id'}"},
                              "<span class=\"age\">$tag{'age'}</span>" .  escapeHTML($tag{'name'})) . "\n" .
                              "</div>\n";
                }
        }
        print "<div class=\"list\"><br/></div>\n";
        git_footer_html();
}

sub git_get_hash_by_path {
        my $base = shift;
        my $path = shift;

        my $tree = $base;
        my @parts = split '/', $path;
        while (my $part = shift @parts) {
                open my $fd, "-|", "$gitbin/git-ls-tree $tree" || die_error(undef, "Open git-ls-tree failed.");
                my (@entries) = map { chomp; $_ } <$fd>;
                close $fd || return undef;
                foreach my $line (@entries) {
                        #'100644        blob    0fa3f3a66fb6a137f6ec2c19351ed4d807070ffa        panic.c'
                        $line =~ m/^([0-9]+)\t(.*)\t(.*)\t(.*)$/;
                        my $t_mode = $1;
                        my $t_type = $2;
                        my $t_hash = $3;
                        my $t_name = $4;
                        if ($t_name eq $part) {
                                if (!(@parts)) {
                                        return $t_hash;
                                }
                                if ($t_type eq "tree") {
                                        $tree = $t_hash;
                                }
                                last;
                        }
                }
        }
}

sub git_blob {
        if (!defined $hash && defined $file_name) {
                my $base = $hash_base || git_read_hash("$project/HEAD");
                $hash = git_get_hash_by_path($base, $file_name, "blob");
        }
        open my $fd, "-|", "$gitbin/git-cat-file blob $hash" || die_error(undef, "Open failed.");
        my $base = $file_name || "";
        git_header_html();
        if (defined $hash_base && (my %co = git_read_commit($hash_base))) {
                print "<div class=\"page_nav\">\n" .
                      $cgi->a({-href => "$my_uri?p=$project;a=commit;h=$hash_base"}, "commit") .
                      " | " . $cgi->a({-href => "$my_uri?p=$project;a=commitdiff;h=$hash_base"}, "commitdiff") .
                      " | " . $cgi->a({-href => "$my_uri?p=$project;a=tree;h=$co{'tree'};hb=$hash_base"}, "tree");
                if (defined $file_name) {
                        print " | " . $cgi->a({-href => "$my_uri?p=$project;a=history;h=$hash_base;f=$file_name"}, "history");
                }
                print "<br/><br/>\n" .
                      "</div>\n";
                print "<div>" .
                      $cgi->a({-href => "$my_uri?p=$project;a=commit;h=$hash_base", -class => "title"}, escapeHTML($co{'title'})) .
                      "</div>\n";
        } else {
                print "<div class=\"page_nav\">\n" .
                      "<br/><br/></div>\n" .
                      "<div class=\"title\">$hash</div>\n";
        }
        if (defined $file_name) {
                print "<div class=\"page_path\">/$file_name</div>\n";
        }
        print "<div class=\"page_body\">\n";
        my $nr;
        while (my $line = <$fd>) {
                chomp $line;
                $nr++;
                print "<div class=\"pre\">";
                printf "<span style=\"color:#999999;\">%4i</span>", $nr;
                print " " .escapeHTML($line) . "</div>\n";
        }
        close $fd || print "Reading blob failed.\n";
        print "</div>";
        git_footer_html();
}

sub git_tree {
        if (!defined $hash) {
                $hash = git_read_hash("$project/HEAD");
                if (defined $file_name) {
                        my $base = $hash_base || git_read_hash("$project/HEAD");
                        $hash = git_get_hash_by_path($base, $file_name, "tree");
                }
        }
        if (!defined $hash_base) {
                $hash_base = git_read_hash("$project/HEAD");
        }
        open my $fd, "-|", "$gitbin/git-ls-tree $hash" || die_error(undef, "Open git-ls-tree failed.");
        my (@entries) = map { chomp; $_ } <$fd>;
        close $fd || die_error(undef, "Reading tree failed.");

        git_header_html();
        my $base_key = "";
        my $file_key = "";
        my $base = "";
        if (defined $hash_base && (my %co = git_read_commit($hash_base))) {
                $base_key = ";hb=$hash_base";
                print "<div class=\"page_nav\">\n" .
                      $cgi->a({-href => "$my_uri?p=$project;a=log"}, "log") .
                      " | " . $cgi->a({-href => "$my_uri?p=$project;a=commit;h=$hash_base"}, "commit") .
                      " | " . $cgi->a({-href => "$my_uri?p=$project;a=commitdiff;h=$hash_base"}, "commitdiff") .
                      " | " . $cgi->a({-href => "$my_uri?p=$project;a=tree;h=$co{'tree'};hb=$hash_base"}, "tree") .
                      "<br/><br/>\n" .
                      "</div>\n";
                print "<div>\n" .
                      $cgi->a({-href => "$my_uri?p=$project;a=commit;h=$hash_base", -class => "title"}, escapeHTML($co{'title'})) . "\n" .
                      "</div>\n";
        } else {
                print "<div class=\"page_nav\">\n";
                print "<br/><br/></div>\n";
                print "<div class=\"title\">$hash</div>\n";
        }
        if (defined $file_name) {
                $base = "$file_name/";
                print "<div class=\"page_path\">/$file_name</div>\n";
        } else {
                print "<div class=\"page_path\">/</div>\n";
        }
        print "<div class=\"page_body\">\n";
        print "<table cellspacing=\"0\">\n";
        foreach my $line (@entries) {
                #'100644        blob    0fa3f3a66fb6a137f6ec2c19351ed4d807070ffa        panic.c'
                $line =~ m/^([0-9]+)\t(.*)\t(.*)\t(.*)$/;
                my $t_mode = $1;
                my $t_type = $2;
                my $t_hash = $3;
                my $t_name = $4;
                $file_key = ";f=$base$t_name";
                print "<tr>\n" .
                      "<td class=\"pre\">" . mode_str($t_mode) . "</td>\n";
                if ($t_type eq "blob") {
                        print "<td class=\"pre\">$t_name</td>\n";
                        print "<td class=\"link\">" .
                              $cgi->a({-href => "$my_uri?p=$project;a=blob;h=$t_hash" . $base_key . $file_key}, "blob") .
                              " | " . $cgi->a({-href => "$my_uri?p=$project;a=history;h=$hash_base" . $file_key}, "history") .
                              "</td>\n";
                } elsif ($t_type eq "tree") {
                        print "<td class=\"pre\">" .
                              $cgi->a({-href => "$my_uri?p=$project;a=tree;h=$t_hash" . $base_key . $file_key}, $t_name) .
                              "</td>\n";
                }
                print "</tr>\n";
        }
        print "</table>\n" .
              "</div>";
        git_footer_html();
}

sub git_rss {
        open my $fd, "-|", "$gitbin/git-rev-list --max-count=20 " . git_read_hash("$project/HEAD") || die_error(undef, "Open failed.");
        my (@revlist) = map { chomp; $_ } <$fd>;
        close $fd || die_error(undef, "Reading rev-list failed.");

        print $cgi->header(-type => 'text/xml', -charset => 'utf-8');
        print "<?xml version=\"1.0\" encoding=\"utf-8\"?>\n".
              "<rss version=\"0.91\">\n";
        print "<channel>\n";
        print "<title>$project</title>\n".
              "<link> $my_url/$project/log</link>\n".
              "<description>$project log</description>\n".
              "<language>en</language>\n";

        foreach my $commit (@revlist) {
                my %co = git_read_commit($commit);
                my %ad = date_str($co{'author_epoch'});
                print "<item>\n" .
                      "\t<title>" . sprintf("%d %s %02d:%02d", $ad{'mday'}, $ad{'month'}, $ad{'hour'}, $ad{'minute'}) . " - " . escapeHTML($co{'title'}) . "</title>\n" .
                      "\t<link> $my_url?p=$project;a=commit;h=$commit</link>\n" .
                      "\t<description>";
                my $comment = $co{'comment'};
                foreach my $line (@$comment) {
                        print escapeHTML($line) . "<br/>\n";
                }
                print "\t</description>\n" .
                      "</item>\n";
        }
        print "</channel></rss>";
}

sub git_log {
        my $head = git_read_hash("$project/HEAD");
        my $limit_option = "";
        if (!defined $time_back) {
                $limit_option = "--max-count=10";
        } elsif ($time_back > 0) {
                my $date = time - $time_back*24*60*60;
                $limit_option = "--max-age=$date";
        }
        open my $fd, "-|", "$gitbin/git-rev-list $limit_option $head" || die_error(undef, "Open failed.");
        my (@revlist) = map { chomp; $_ } <$fd>;
        close $fd || die_error(undef, "Reading rev-list failed.");

        git_header_html();
        print "<div class=\"page_nav\">\n";
        print $cgi->a({-href => "$my_uri?p=$project;a=log"}, "last 10") . " | " .
              $cgi->a({-href => "$my_uri?p=$project;a=log;t=1"}, "day") . " | " .
              $cgi->a({-href => "$my_uri?p=$project;a=log;t=7"}, "week") . " | " .
              $cgi->a({-href => "$my_uri?p=$project;a=log;t=31"}, "month") . " | " .
              $cgi->a({-href => "$my_uri?p=$project;a=log;t=365"}, "year") . " | " .
              $cgi->a({-href => "$my_uri?p=$project;a=log;t=0"}, "all") . "<br/>\n";
        print "<br/>\n" .
              "</div>\n";

        if (!@revlist) {
                my %co = git_read_commit($head);
                print "<div class=\"page_body\"> Last change $co{'age_string'}.<br/><br/></div>\n";
        }

        foreach my $commit (@revlist) {
                my %co = git_read_commit($commit);
                next if !%co;
                my %ad = date_str($co{'author_epoch'});
                print "<div>\n" .
                      $cgi->a({-href => "$my_uri?p=$project;a=commit;h=$commit", -class => "title"},
                      "<span class=\"age\">$co{'age_string'}</span>" . escapeHTML($co{'title'})) . "\n" .
                      "</div>\n";
                print "<div class=\"title_text\">\n" .
                      "<div class=\"log_link\">\n" .
                      $cgi->a({-href => "$my_uri?p=$project;a=commit;h=$commit"}, "commit") .
                      " | " . $cgi->a({-href => "$my_uri?p=$project;a=commitdiff;h=$commit"}, "commitdiff") .
                      "<br/>\n" .
                      "</div>\n" .
                      "<i>" . escapeHTML($co{'author_name'}) .  " [$ad{'rfc2822'}]</i><br/>\n" .
                      "</div>\n" .
                      "<div class=\"log_body\">\n";
                my $comment = $co{'comment'};
                my $empty = 0;
                foreach my $line (@$comment) {
                        if ($line =~ m/^(signed[ \-]off[ \-]by[ :]|acked[ \-]by[ :]|cc[ :])/i) {
                                next;
                        }
                        if ($line eq "") {
                                if ($empty) {
                                        next;
                                }
                                $empty = 1;
                        } else {
                                $empty = 0;
                        }
                        print escapeHTML($line) . "<br/>\n";
                }
                if (!$empty) {
                        print "<br/>\n";
                }
                print "</div>\n";
        }
        git_footer_html();
}

sub git_commit {
        my %co = git_read_commit($hash);
        if (!%co) {
                die_error(undef, "Unknown commit object.");
        }
        my %ad = date_str($co{'author_epoch'}, $co{'author_tz'});
        my %cd = date_str($co{'committer_epoch'}, $co{'committer_tz'});

        my @difftree;
        if (defined $co{'parent'}) {
                open my $fd, "-|", "$gitbin/git-diff-tree -r $co{'parent'} $hash" || die_error(undef, "Open failed.");
                @difftree = map { chomp; $_ } <$fd>;
                close $fd || die_error(undef, "Reading diff-tree failed.");
        } else {
                # fake git-diff-tree output for initial revision
                open my $fd, "-|", "$gitbin/git-ls-tree -r $hash" || die_error(undef, "Open failed.");
                @difftree = map { chomp;  "+" . $_ } <$fd>;
                close $fd || die_error(undef, "Reading ls-tree failed.");
        }
        git_header_html();
        print "<div class=\"page_nav\">\n" .
              $cgi->a({-href => "$my_uri?p=$project;a=log"}, "log") .
              " | " . $cgi->a({-href => "$my_uri?p=$project;a=commit;h=$hash"}, "commit");
        if (defined $co{'parent'}) {
                print " | " . $cgi->a({-href => "$my_uri?p=$project;a=commitdiff;h=$hash"}, "commitdiff");
        }
        print " | " . $cgi->a({-href => "$my_uri?p=$project;a=tree;h=$co{'tree'};hb=$hash"}, "tree") . "\n" .
              "<br/><br/></div>\n";
        if (defined $co{'parent'}) {
                print "<div>\n" .
                      $cgi->a({-href => "$my_uri?p=$project;a=commitdiff;h=$hash", -class => "title"}, escapeHTML($co{'title'})) . "\n" .
                      "</div>\n";
        } else {
                print "<div>\n" .
                      $cgi->a({-href => "$my_uri?p=$project;a=tree;h=$co{'tree'};hb=$hash", -class => "title"}, escapeHTML($co{'title'})) . "\n" .
                      "</div>\n";
        }
        print "<div class=\"title_text\">\n" .
              "<table cellspacing=\"0\">\n";
        print "<tr><td>author</td><td>" . escapeHTML($co{'author'}) . "</td></tr>\n".
              "<tr><td></td><td> $ad{'rfc2822'}";
        if ($ad{'hour_local'} < 6) {
                printf(" (<span style=\"color: #cc0000;\">%02d:%02d</span> %s)", $ad{'hour_local'}, $ad{'minute_local'}, $ad{'tz_local'});
        } else {
                printf(" (%02d:%02d %s)", $ad{'hour_local'}, $ad{'minute_local'}, $ad{'tz_local'});
        }
        print "</td></tr>\n";
        print "<tr><td>committer</td><td>" . escapeHTML($co{'committer'}) . "</td></tr>\n";
        print "<tr><td></td><td> $cd{'rfc2822'}" . sprintf(" (%02d:%02d %s)", $cd{'hour_local'}, $cd{'minute_local'}, $cd{'tz_local'}) . "</td></tr>\n";
        print "<tr><td>commit</td><td style=\"font-family: monospace;\">$hash</td></tr>\n";
        print "<tr><td>tree</td><td style=\"font-family: monospace;\">" .
              $cgi->a({-href => "$my_uri?p=$project;a=tree;h=$co{'tree'};hb=$hash"}, $co{'tree'}) . "</td></tr>\n";
        my $parents  = $co{'parents'};
        foreach my $par (@$parents) {
                print "<tr><td>parent</td><td style=\"font-family: monospace;\">" .
                      $cgi->a({-href => "$my_uri?p=$project;a=commit;h=$par"}, $par) . "</td></tr>\n";
        }
        print "</table>". 
              "</div>\n";
        print "<div class=\"page_body\">\n";
        my $comment = $co{'comment'};
        my $empty = 0;
        my $signed = 0;
        foreach my $line (@$comment) {
                # print only one empty line
                if ($line eq "") {
                        if ($empty || $signed) {
                                next;
                        }
                        $empty = 1;
                } else {
                        $empty = 0;
                }
                if ($line =~ m/^(signed[ \-]off[ \-]by[ :]|acked[ \-]by[ :]|cc[ :])/i) {
                        $signed = 1;
                        print "<span style=\"color: #888888\">" . escapeHTML($line) . "</span><br/>\n";
                } else {
                        $signed = 0;
                        print escapeHTML($line) . "<br/>\n";
                }
        }
        print "</div>\n";
        print "<div class=\"list_head\">\n";
        if ($#difftree > 10) {
                print(($#difftree + 1) . " files changed:\n");
        }
        print "</div>\n";
        foreach my $line (@difftree) {
                # '*100644->100644      blob    9f91a116d91926df3ba936a80f020a6ab1084d2b->bb90a0c3a91eb52020d0db0e8b4f94d30e02d596      net/ipv4/route.c'
                # '+100644      blob    4a83ab6cd565d21ab0385bac6643826b83c2fcd4        arch/arm/lib/bitops.h'
                # '*100664->100644      blob    b1a8e3dd5556b61dd771d32307c6ee5d7150fa43->b1a8e3dd5556b61dd771d32307c6ee5d7150fa43      show-files.c'
                # '*100664->100644      blob    d08e895238bac36d8220586fdc28c27e1a7a76d3->d08e895238bac36d8220586fdc28c27e1a7a76d3      update-cache.c'
                $line =~ m/^(.)(.*)\t(.*)\t(.*)\t(.*)$/;
                my $op = $1;
                my $mode = $2;
                my $type = $3;
                my $id = $4;
                my $file = $5;
                if ($type eq "blob") {
                        if ($op eq "+") {
                                my $mode_chng = "";
                                if (S_ISREG(oct $mode)) {
                                        $mode_chng = sprintf(" with mode: %04o", (oct $mode) & 0777);
                                }
                                print "<div class=\"list\">\n" .
                                      $cgi->a({-href => "$my_uri?p=$project;a=blob;h=$id;hb=$hash;f=$file"},
                                      escapeHTML($file) . " <span style=\"color: #008000;\">[new " . file_type($mode) . "$mode_chng]</span>") . "\n" .
                                      "</div>\n";
                                print "<div class=\"list_link\">\n" .
                                      $cgi->a({-href => "$my_uri?p=$project;a=blob;h=$id;hb=$hash;f=$file"}, "blob") . "\n" .
                                      "</div>\n";
                        } elsif ($op eq "-") {
                                print "<div class=\"list\">\n" .
                                      $cgi->a({-href => "$my_uri?p=$project;a=blob;h=$id;hb=$hash;f=$file"},
                                      escapeHTML($file) .  " <span style=\"color: #c00000;\">[deleted " . file_type($mode) . "]</span>") . "\n" .
                                      "</div>";
                                print "<div class=\"list_link\">\n" .
                                      $cgi->a({-href => "$my_uri?p=$project;a=blob;h=$id;hb=$hash;f=$file"}, "blob") . " | " .
                                      $cgi->a({-href => "$my_uri?p=$project;a=history;h=$hash;f=$file"}, "history") . "\n" .
                                      "</div>\n";
                        } elsif ($op eq "*") {
                                $id =~ m/([0-9a-fA-F]+)->([0-9a-fA-F]+)/;
                                my $from_id = $1;
                                my $to_id = $2;
                                $mode =~ m/^([0-7]{6})->([0-7]{6})$/;
                                my $from_mode = $1;
                                my $to_mode = $2;
                                my $mode_chnge = "";
                                if ($from_mode != $to_mode) {
                                        $mode_chnge = " <span style=\"color: #777777;\">[changed";
                                        if (((oct $from_mode) & S_IFMT) != ((oct $to_mode) & S_IFMT)) {
                                                $mode_chnge .= " from " . file_type($from_mode) . " to " . file_type($to_mode);
                                        }
                                        if (((oct $from_mode) & 0777) != ((oct $to_mode) & 0777)) {
                                                if (S_ISREG($from_mode) && S_ISREG($to_mode)) {
                                                        $mode_chnge .= sprintf(" mode: %04o->%04o", (oct $from_mode) & 0777, (oct $to_mode) & 0777);
                                                } elsif (S_ISREG($to_mode)) {
                                                        $mode_chnge .= sprintf(" mode: %04o", (oct $to_mode) & 0777);
                                                }
                                        }
                                        $mode_chnge .= "]</span>\n";
                                }
                                print "<div class=\"list\">\n";
                                if ($to_id ne $from_id) {
                                        print $cgi->a({-href => "$my_uri?p=$project;a=blobdiff;h=$to_id;hp=$from_id;hb=$hash;f=$file"},
                                              escapeHTML($file) . $mode_chnge) . "\n" .
                                              "</div>\n";
                                } else {
                                        print $cgi->a({-href => "$my_uri?p=$project;a=blob;h=$to_id;hb=$hash;f=$file"},
                                              escapeHTML($file) . $mode_chnge) . "\n" .
                                              "</div>\n";
                                }
                                print "<div class=\"list_link\">\n";
                                if ($to_id ne $from_id) {
                                        print $cgi->a({-href => "$my_uri?p=$project;a=blobdiff;h=$to_id;hp=$from_id;hb=$hash;f=$file"}, "diff") . " | ";
                                }
                                print $cgi->a({-href => "$my_uri?p=$project;a=blob;h=$to_id;hb=$hash;f=$file"}, "blob") . " | " .
                                      $cgi->a({-href => "$my_uri?p=$project;a=history;h=$hash;f=$file"}, "history") . "\n" .
                                      "</div>\n";
                        }
                }
        }
        git_footer_html();
}

sub git_blobdiff {
        mkdir($gittmp, 0700);
        git_header_html();
        if (defined $hash_base && (my %co = git_read_commit($hash_base))) {
                print "<div class=\"page_nav\">\n" .
                      $cgi->a({-href => "$my_uri?p=$project;a=log"}, "log") .
                      " | " . $cgi->a({-href => "$my_uri?p=$project;a=commit;h=$hash_base"}, "commit") .
                      " | " . $cgi->a({-href => "$my_uri?p=$project;a=commitdiff;h=$hash_base"}, "commitdiff") .
                      " | " . $cgi->a({-href => "$my_uri?p=$project;a=tree;h=$co{'tree'};hb=$hash_base"}, "tree");
                        if (defined $file_name) {
                                print " | " . $cgi->a({-href => "$my_uri?p=$project;a=history;h=$hash_base;f=$file_name"}, "history");
                        }
                print "<br/><br/>\n" .
                      "</div>\n";
                print "<div>\n" .
                      $cgi->a({-href => "$my_uri?p=$project;a=commit;h=$hash_base", -class => "title"}, escapeHTML($co{'title'})) . "\n" .
                      "</div>\n";
        } else {
                print "<div class=\"page_nav\">\n" .
                      "<br/><br/></div>\n" .
                      "<div class=\"title\">$hash vs $hash_parent</div>\n";
        }
        if (defined $file_name) {
                print "<div class=\"page_path\">\n" .
                      "/$file_name\n" .
                      "</div>\n";
        }
        print "<div class=\"page_body\">\n" .
              "<div class=\"diff_info\">blob:" .
              $cgi->a({-href => "$my_uri?p=$project;a=blob;h=$hash_parent;hb=$hash_base;f=$file_name"}, $hash_parent) .
              " -> blob:" .
              $cgi->a({-href => "$my_uri?p=$project;a=blob;h=$hash;hb=$hash_base;f=$file_name"}, $hash) .
              "</div>\n";
        git_diff_html($hash_parent, $file_name || $hash_parent, $hash, $file_name || $hash);
        print "</div>";
        git_footer_html();
}

sub git_commitdiff {
        mkdir($gittmp, 0700);
        my %co = git_read_commit($hash);
        if (!%co) {
                die_error(undef, "Unknown commit object.");
        }
        open my $fd, "-|", "$gitbin/git-diff-tree -r $co{'parent'} $hash" || die_error(undef, "Open failed.");
        my (@difftree) = map { chomp; $_ } <$fd>;
        close $fd || die_error(undef, "Reading diff-tree failed.");

        git_header_html();
        print "<div class=\"page_nav\">\n" .
              $cgi->a({-href => "$my_uri?p=$project;a=log"}, "log") .
              " | " . $cgi->a({-href => "$my_uri?p=$project;a=commit;h=$hash"}, "commit") .
              " | " . $cgi->a({-href => "$my_uri?p=$project;a=commitdiff;h=$hash"}, "commitdiff") .
              " | " . $cgi->a({-href => "$my_uri?p=$project;a=tree;h=" .  $co{'tree'} . ";hb=$hash"}, "tree") .
              "<br/><br/></div>\n";
        print "<div>\n" .
              $cgi->a({-href => "$my_uri?p=$project;a=commit;h=$hash", -class => "title"}, escapeHTML($co{'title'})) . "\n" .
              "</div>\n";
        print "<div class=\"page_body\">\n";
        foreach my $line (@difftree) {
                # '*100644->100644      blob    8e5f9bbdf4de94a1bc4b4da8cb06677ce0a57716->8da3a306d0c0c070d87048d14a033df02f40a154      Makefile'
                $line =~ m/^(.)(.*)\t(.*)\t(.*)\t(.*)$/;
                my $op = $1;
                my $mode = $2;
                my $type = $3;
                my $id = $4;
                my $file = $5;
                if ($type eq "blob") {
                        if ($op eq "+") {
                                print "<div class=\"diff_info\">" .  file_type($mode) . ":" .
                                      $cgi->a({-href => "$my_uri?p=$project;a=blob;h=$id;hb=$hash;f=$file"}, $id) . "(new)" .
                                      "</div>\n";
                                git_diff_html(undef, "/dev/null", $id, "b/$file");
                        } elsif ($op eq "-") {
                                print "<div class=\"diff_info\">" . file_type($mode) . ":" .
                                      $cgi->a({-href => "$my_uri?p=$project;a=blob;h=$id;hb=$hash;f=$file"}, $id) . "(deleted)" .
                                      "</div>\n";
                                git_diff_html($id, "a/$file", undef, "/dev/null");
                        } elsif ($op eq "*") {
                                $id =~ m/([0-9a-fA-F]+)->([0-9a-fA-F]+)/;
                                my $from_id = $1;
                                my $to_id = $2;
                                $mode =~ m/([0-7]+)->([0-7]+)/;
                                my $from_mode = $1;
                                my $to_mode = $2;
                                if ($from_id ne $to_id) {
                                        print "<div class=\"diff_info\">" .
                                              file_type($from_mode) . ":" . $cgi->a({-href => "$my_uri?p=$project;a=blob;h=$from_id;hb=$hash;f=$file"}, $from_id) .
                                              " -> " .
                                              file_type($to_mode) . ":" . $cgi->a({-href => "$my_uri?p=$project;a=blob;h=$to_id;hb=$hash;f=$file"}, $to_id);
                                        print "</div>\n";
                                        git_diff_html($from_id, "a/$file",  $to_id, "b/$file");
                                }
                        }
                }
        }
        print "<br/>\n" .
              "</div>";
        git_footer_html();
}

sub git_history {
        if (!defined $hash) {
                $hash = git_read_hash("$project/HEAD");
        }
        my %co = git_read_commit($hash);
        if (!%co) {
                die_error(undef, "Unknown commit object.");
        }
        git_header_html();
        print "<div class=\"page_nav\">\n" .
              $cgi->a({-href => "$my_uri?p=$project;a=commit;h=$hash"}, "commit") . " | " .
              $cgi->a({-href => "$my_uri?p=$project;a=commitdiff;h=$hash"}, "commitdiff") . " | " .
              $cgi->a({-href => "$my_uri?p=$project;a=tree;h=$co{'tree'};hb=$hash"}, "tree") .
              "<br/><br/>\n" .
              "</div>\n";
        print "<div>\n" .
              $cgi->a({-href => "$my_uri?p=$project;a=commit;h=$hash", -class => "title"}, escapeHTML($co{'title'})) . "\n" .
              "</div>\n";
        print "<div class=\"page_path\">\n" .
              "/$file_name<br/>\n";
        print "</div>\n";
        open my $fd, "-|", "$gitbin/git-rev-list $hash | $gitbin/git-diff-tree -r --stdin $file_name";
        my $commit;
        while (my $line = <$fd>) {
                if ($line =~ m/^([0-9a-fA-F]{40}) /){
                        $commit = $1;
                        next;
                }
                if ($line =~ m/^(.)(.*)\t(.*)\t(.*)\t(.*)$/ && (defined $commit)) {
                        my $type = $3;
                        my $file = $5;
                        if ($file ne $file_name || $type ne "blob") {
                                next;
                        }
                        my %co = git_read_commit($commit);
                        if (!%co) {
                                next;
                        }
                        print "<div class=\"list\">\n" .
                              $cgi->a({-href => "$my_uri?p=$project;a=commit;h=$commit"},
                              "<span class=\"age\">$co{'age_string'}</span>" . escapeHTML($co{'title'})) . "\n" .
                              "</div>\n";
                        print "<div class=\"list_link\">\n" .
                              $cgi->a({-href => "$my_uri?p=$project;a=commit;h=$commit"}, "commit") .
                              " | " . $cgi->a({-href => "$my_uri?p=$project;a=tree;h=" .  $co{'tree'} . ";hb=$commit"}, "tree") .
                              " | " . $cgi->a({-href => "$my_uri?p=$project;a=blob;hb=$commit;f=$file"}, "blob");
                        my $blob = git_get_hash_by_path($hash, $file_name);
                        my $blob_parent = git_get_hash_by_path($commit, $file_name);
                        if (defined $blob && defined $blob_parent && $blob ne $blob_parent) {
                                print " | " . $cgi->a({-href => "$my_uri?p=$project;a=blobdiff;h=$blob;hp=$blob_parent;hb=$commit;f=$file"}, "diff");
                        }
                        print "<br/>\n" .
                              "</div>\n";
                        undef $commit;
                }
        }
        close $fd;
        git_footer_html();
}