轻松获取Google PageRank值的源码_PHP

Google

　　最近对google的PageRank比较感兴趣，一直想知道如何不用google toolbar来获取pr值。用嗅探工具获得google toolbar发出请求的url为:http://toolbarqueries.google.com//search?client=navclient-auto&ch=64170410360&ie=UTF-8&oe=UTF-8&features=Rank:FVN&q=info:http://www.ugia.cn,其中的关键部分为ch=64170410360,即CheckSum,不知道这个是用的什么算法得出来的。

　　苦苦搜索之后,找到如下代码:

　　转自: http://meese.ath.cx/google via 思路(http://silu.spirezone.com)

/**
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 $c -= $a; $c -= $b; $c ^= (zeroFill($b,13));
$a -= $b; $a -= $c; $a ^= (zeroFill($c,12));
$b -= $c; $b -= $a; $b ^= ($a $c -= $a; $c -= $b; $c ^= (zeroFill($b,5));
$a -= $b; $a -= $c; $a ^= (zeroFill($c,3));
$b -= $c; $b -= $a; $b ^= ($a $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] $b = ($url[$k 4] ($url[$k 5] $c = ($url[$k 8] ($url[$k 9] $mix = mix($a,$b,$c);
$a = $mix[0]; $b = $mix[1]; $c = $mix[2];
$k = 12;
$len -= 12;
}

$c = $length;
switch($len) /* all the case statements fall through */
{
case 11: $c =($url[$k 10] case 10: $c =($url[$k 9] case 9 : $c =($url[$k 8] /* the first byte of c is reserved for the length */
case 8 : $b =($url[$k 7] case 7 : $b =($url[$k 6] case 6 : $b =($url[$k 5] case 5 : $b =($url[$k 4]);
case 4 : $a =($url[$k 3] case 3 : $a =($url[$k 2] case 2 : $a =($url[$k 1] 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 $result[$i] = ord($string{$i});
}
return $result;
}
// http://www.example.com/ - Checksum: 6540747202
$url = 'info:'.$_GET['url'];
$ch = GoogleCH(strord($url));
$url='info:'.urlencode($_GET['url']);
echo file_get_contents("http://www.google.com/search?client=

navclient-auto&ch=6$ch&ie=UTF-8&oe=UTF-8&features=Rank&q=$url");
/* use curl send the user angent
$curl = curl_init("http://www.google.com/search?client=navclient-auto&ch=6$

ch&ie=UTF-8&oe=UTF-8&features=Rank&q=$url");
curl_setopt ($curl, CURLOPT_USERAGENT, "Mozilla/4.0 (compatible;

GoogleToolbar 2.0.110-big; Windows 2000 5.0)");
curl_exec($curl);
*/
?>
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