<?php
/*
	This code is released unto the public domain
*/
header("Content-Type: text/plain; charset=utf-8");
define('GOOGLE_MAGIC', 0xE6359A60);

//unsigned shift right
function zeroFill($a, $b) {
	$z = hexdec(80000000);

	if ($z & $a) {
		$a = ($a>>1);
		$a &= (~$z);
		$a |= 0x40000000;
		$a = ($a>>($b-1));
	} else {
		$a = ($a>>$b);
	}

	return $a;
}

function mix($a,$b,$c) {
	$a -= $b; $a -= $c; $a ^= (zeroFill($c,13));
	$b -= $c; $b -= $a; $b ^= ($a<<8);
	$c -= $a; $c -= $b; $c ^= (zeroFill($b,13));
	$a -= $b; $a -= $c; $a ^= (zeroFill($c,12));
	$b -= $c; $b -= $a; $b ^= ($a<<16);
	$c -= $a; $c -= $b; $c ^= (zeroFill($b,5));
	$a -= $b; $a -= $c; $a ^= (zeroFill($c,3));
	$b -= $c; $b -= $a; $b ^= ($a<<10);
	$c -= $a; $c -= $b; $c ^= (zeroFill($b,15));

	return array($a,$b,$c);
}

function GoogleCH($url, $length=null, $init=GOOGLE_MAGIC) {
	if(is_null($length)) {
		$length = sizeof($url);
	}
	$a = $b = 0x9E3779B9;
	$c = $init;
	$k = 0;
	$len = $length;
    while ($len >= 12) {
		$a += ($url[$k+0] + ($url[$k+1]<<8) + ($url[$k+2]<<16) + ($url[$k+3]<<24));
		$b += ($url[$k+4] + ($url[$k+5]<<8) + ($url[$k+6]<<16) + ($url[$k+7]<<24));
		$c += ($url[$k+8] + ($url[$k+9]<<8) + ($url[$k+10]<<16) + ($url[$k+11]<<24));
		$mix = mix($a,$b,$c);
		$a = $mix[0]; $b = $mix[1]; $c = $mix[2];
		$k += 12;
		$len -= 12;
	}

	$c += $length;
	/* all the case statements fall through */
	switch($len) { 
		case 11: $c+=($url[$k+10]<<24);
		case 10: $c+=($url[$k+9]<<16);
		case 9 : $c+=($url[$k+8]<<8);
		/* the first byte of c is reserved for the length */ 
		case 8 : $b+=($url[$k+7]<<24);
		case 7 : $b+=($url[$k+6]<<16);
		case 6 : $b+=($url[$k+5]<<8);
		case 5 : $b+=($url[$k+4]);
		case 4 : $a+=($url[$k+3]<<24);
		case 3 : $a+=($url[$k+2]<<16);
		case 2 : $a+=($url[$k+1]<<8);
		case 1 : $a+=($url[$k+0]);
		/* case 0: nothing left to add */
	}
    $mix = mix($a,$b,$c);
    /*-------------------------------------------- report the result */ 
    return $mix[2]; 
} 

//converts a string into an array of integers containing the numeric value of the char 
function strord($string) { 
	for ($i = 0; $i < strlen($string); $i++) {
		$result[$i] = ord($string{$i});
	}
	return $result;
}

// [url]http://www.example.com/[/url] - Checksum: 6540747202 
$url = 'info:' . $_GET['url']; 
$ch = GoogleCH(strord($url));
printf("url:\t%s\n", $_GET['url']);
printf("ch:\t6%u\n", $ch);
printf("google:\thttp://www.google.co.jp/search?client=navclient-auto&ch=6%u&q=%s\n", $ch, $url);
?>