#!/usr/bin/perl

#///// ycount v1.3 /////
#(C)1997 Yasuyuki Ogawa

#directory no settei
$image='./number/';
$kazu='./kazu';
$lockfile='./lockcheck/tukatteru';

#parameter wo torikomu
$_ = $ENV{'QUERY_STRING'};
($keta, $flag) = /keta\=(\d+)(\+?)/;
unless ($keta) {
	exit(0);
}

#siyouchuuka douka wo shiraberu
$loop = 0;
until(symlink("$kazu", "$lockfile")){
	if(++$loop >= 10){
		unlink("$lockfile");
		exit(0);
	}
	sleep(1);
}

#main script
open(KA, "<$kazu");
$cnt = <KA>;
close(KA);
if ($flag eq "+"){
	$cnt++;
	open(KI, ">$kazu");
	print KI $cnt;
	close(KI);
}
unlink("$lockfile");
$num = $cnt < 10**($keta-1) ? 0 : substr($cnt, -$keta, 1);
if (open(IMAGE, "<$image$num.gif")) {
	print "Content-type: image/gif\n\n";
	while (<IMAGE>) {
		print;
	}
	close(IMAGE);
}