#!/usr/local/bin/perl
#
###   CGIカウンター SDcountH Ver.1.00
###	(イメージタグ埋め込み型)
###
###	Copyright (c) 2001 Sentora Dori
###	http://lowpower.iis.u-tokyo.ac.jp/~hat
#
#################### 変数設定 ####################

# カウンタファイルをおくディレクトリのパス
$basedir = ".";

#################### 変数設定(ここまで) ####################

# 2: flockを使用する 1: ロックファイルでロックする 0: ロックしない (通常は変更必要なし)
$uselock = 2;
# flockを使用しないロックのときのロックファイル名のベース (変更必要なし)
$baselockfile = './SDlock';

### data format ###

require './gifcat.pl';
&init_form();

$countfile = "$basedir/$countname.txt";

### get host ###

$hostaddr = $ENV{'REMOTE_ADDR'};
$hostname = $ENV{'REMOTE_HOST'};
if ($hostaddr eq $hostname || $hostname eq '') {
    $hostname = gethostbyaddr(pack("C4", split(/\./, $hostaddr)), 2);
}

### data file open ###

if (!open(OUT, "+<$countfile")) {
    &print_error('[no counter data]');
}

# file lock
if (!&lock_file(OUT)) {
    &print_error('[lock error]');
}

# image file check
if (!(-f "$gifdir/0.gif")){
    &print_error("[no image files]");
}

### get counter ###

seek(OUT, 0, 0);
$totalcount = 1 + <OUT>;
$yesterdaycount = 0 + <OUT>;
$todaycount = 1 + <OUT>;
$lastday = <OUT>;
$lasthost = <OUT>;
chomp($lasthost);

### reload? ###

if (($ban_reload || !$countup) && $hostaddr eq $lasthost) {
    $totalcount--;
    $todaycount--;
    &unlock_file(OUT);
    close(OUT);
    if ($usecookie) {
        $nochange = 1;
        $yourcount--;
    }
    goto SHOWPAGE;
}

### get time ###

($sec, $min, $hour, $day, $mon, $year) = localtime(time);
$mon++;
$year += 1900;
$today = "$year-$mon-$day\n";

### first access today? ###

if ($today ne $lastday) {
    ($sec2, $min2, $hour2, $day2, $mon2, $year2) = localtime(time - 24*60*60);
    $mon2++;
    $year2 += 1900;
    $yesterday ="$year2-$mon2-$day2\n";
   if ($yesterday ne $lastday) {
        $yesterdaycount = 0;
    } else {
        $yesterdaycount = $todaycount - 1;
    }
    $todaycount =1;
    $lastday = $today;
}

### put counter ###

seek(OUT, 0, 0);
print OUT "$totalcount\n";
print OUT "$yesterdaycount\n";
print OUT "$todaycount\n";
print OUT "$lastday";
print OUT "$hostaddr\n";
&unlock_file(OUT);
close(OUT);

### html header ###

SHOWPAGE:

print "Content-type: image/gif\n";
print "\n";

### showcounter ###

$count = $totalcount;
$count = $yesterdaycount if ($type eq 'yesterday');
$count = $todaycount if ($type eq 'today');
$count = $yourcount if ($type eq 'your');
&show_counter($count);

### end ###

exit(0);

##################
### subroutine ###
##################

#----- ブラウザへ出力 -----

sub show_counter {
    local($count) = @_;
    @num = split(//, $count);
    if ($counter_order) {
        while (@num < $counter_order) {
            unshift(@num, "0");
        }
    }
    for(0..$#num){ $num[$_]="$gifdir/$num[$_].gif"; }
    binmode(STDOUT);
    $| = 1;
    print &gifcat'gifcat(@num);
}

#----- ブラウザへの入力データの取得 -----

sub init_form {
    local($query, @param, $method);
    $method = $ENV{'REQUEST_METHOD'};
    $method =~ tr/A-Z/a-z/;
    if ($method eq 'post') {
	read(STDIN, $query, $ENV{'CONTENT_LENGTH'});
    } else {
	$query = $ENV{'QUERY_STRING'};
    }
    @param = split(/&/, $query);
    
    $countname = 	($param[0] =~ /^\w+$/) ? $param[0] : '';
    $countup = 		($param[1] == 1) ? $param[1] : 0;
    $type   = 		($param[2] =~ /^\w+$/) ? $param[2] : 'total';
    $counter_order  = 	($param[3] =~ /^\d+$/) ? $param[3] : 5;
    $gifdir  = 		($param[4]) ? $param[4] : './img/default';
    $ban_reload = 	($param[5] == 1) ? $param[5] : 0;
    }

#----- ファイルロック -----

sub lock_file {
    local($FILE) = @_;
    local($LOCK) = "LOCK$FILE";
    local($lockfile) = "$baselockfile$FILE";
    local($retry) = 10;
    if ($uselock == 2) {
        eval(flock($FILE, 2));
        if ($@) {
            return 0;
        } else {
            return 1;
        }
    } elsif ($uselock == 1) {
        while (-f $lockfile) {
            sleep(0.3);
            return 0 if (--$retry <= 0);
        }
        open($LOCK, ">$lockfile") || return 0;
        close($LOCK);
        return 1;
    } else {
        return 1;
    }
}

#----- ファイルアンロック -----

sub unlock_file {
    local($FILE) = @_;
    local($lockfile) = "$baselockfile$FILE";
    if ($uselock == 2) {
        flock($FILE, 8);
    } elsif ($uselock == 1) {
        unlink($lockfile);
    }
}

##### エラー処理 #####

#----- エラー文を出力し終了 -----

sub print_error {
    local($msg) = @_;
    print "Content-type: text/plain\n\n";
    print $msg;
    exit(0);
}