Client.php

<?php
namespace PhpTelnet;

class Client
{

    var $uSleepTime = 1250000;

    var $loginSleepTime = 1000000;

    var $connection = null;

    var $server = null;

    var $port = null;

    var $username = null;

    var $password = null;

    var $loginPrompt;

    var $connMessage1;

    var $connMessage2;

    const ERROR_0 = "success";

    CONST ERROR_1 = "couldn't open network connection";

    const ERROR_2 = "unknown host";

    const ERROR_3 = "login failed";

    public function __construct($server, $port, $username = null, $password = null)
    {
        // we need php 5 obviously
        if (version_compare(phpversion(), '5.0', '<')) {
            throw new \Exception('PhpTelnet\'s Client needs PHP 5+ to work.');
        } else {
            $this->server = $server;
            $this->port = $port;
            $this->username = $username;
            $this->password = $password;
        }
    }

    function connect()
    {
        if ($this->connection === NULL) {
            
            $errorNumber = 0;
            
            if ($this->connection = fsockopen($this->server, $this->port, $errno, $errstr, 5)) {
                
                if ($this->username !== null || $this->password !== null) {
                    
                    $r = $this->getResponse();
                    $r = explode("\n", $r);
                    $this->loginPrompt = $r[count($r) - 1];
                    
                    fputs($this->connection, $this->username . "\r");
                    $this->sleep();
                    
                    fputs($this->connection, $this->password . "\r");
                    $this->sleep($this->loginSleepTime);
                    
                    $r = $this->getResponse();
                    $r = explode("\n", $r);
                    if (($r[count($r) - 1] == '') || ($this->loginPrompt == $r[count($r) - 1])) {
                        $errorNumber = 3;
                        $this->disconnect();
                    }
                }
            } else {
                $errorNumber = 1;
            }
            
            if ($errorNumber != 0) {
                $this->throwConnectError($errorNumber);
            }
        } else {
            return true;
        }
    }

    function disconnect($exit = 'exit')
    {
        if ($this->connection) {
            if ($exit)
                $this->execute($exit);
            fclose($this->connection);
            $this->connection = NULL;
        }
    }

    public function execute($cmd)
    {
        $this->connect();
        fwrite($this->connection, $cmd . "\r\n");
        $this->sleep();
        $r = $this->getResponse();
        return $r;
    }

    private function removeNonPrintableCharacters($str)
    {
        return preg_replace('/[\x00-\x09\x0B\x0C\x0E-\x1F\x7F]/', '', $str);
    }

    function getResponse()
    {
        $r = '';
        do {
            $r .= fread($this->connection, 1000);
            $s = socket_get_status($this->connection);
        } while ($s['unread_bytes']);
        return $this->removeNonPrintableCharacters($r);
    }

    function sleep($sleepTime = null)
    {
        if ($sleepTime === null) {
            usleep($this->uSleepTime);
        } else {
            usleep($this->sleepTime);
        }
    }

    function throwConnectError($num)
    {
        throw new \Exception(constant('ERROR_' . $num));
    }
}