Sntp.php

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<?php
#require_once 'Zend/TimeSync/Protocol.php';

class Zend_TimeSync_Sntp extends Zend_TimeSync_Protocol
{
    protected $_port = 37;

    private $_delay;

    public function __construct($timeserver, $port)
    {
        $this->_timeserver = 'udp://' . $timeserver;
        if ($port !== null) {
            $this->_port = $port;
        }
    }

    protected function _prepare()
    {
        return "\n";
    }

    protected function _read()
    {
        $result       = fread($this->_socket, 49);
        $this->_delay = (($this->_delay - time()) / 2);

        return $result;
    }

    protected function _write($data)
    {
        $this->_connect();
        $this->_delay = time();
        fputs($this->_socket, $data);
    }

    protected function _extract($result)
    {
        $dec   = hexdec('7fffffff');
        $time  = abs(($dec - hexdec(bin2hex($result))) - $dec);
        $time -= 2208988800;
        // Socket delay
        $time -= $this->_delay;

        $this->_info['offset'] = $this->_delay;

        return $time;
    }
}