SSVNCDaemon.php

<?php

// Copyright (C) 2014 Universitätsbibliothek Mannheim
// See file LICENSE for license details.

require_once("DBConnector.class.php");

class SSVNCDaemon {

private $_URL;

// all during session connected VNC Clients
private $_VNC_CLIENTS;

// count of all connected clients
// private $_VNC_CLIENT_COUNT;

// active client count
private $_CONNECTIONS = 0;

// ignored VNC Clients
// TODO: check if no more longer helpful, has to be cleaned
private $_IGNORE_LIST = array();

public $db;

public function __construct() {

    global $db;
    $this->db = $db;

    // Start Vncviewer
    $handle = $this->startVNCViewer();

    // Read log in loop
    $this->readLog($handle);
}

protected function startVNCViewer() {

    $display=":0";

    if (file_exists('palma.ini')) {

        // Get configuration from ini file.
        $conf = parse_ini_file("palma.ini", true);
        $this->_URL = $conf['path']['control_file'];

        $display = $conf['display']['id'];
        if (isset($conf['display']['ssh'])) {
            $ssh = $conf['display']['ssh'];
        }

    } else {

        // Guess configuration from global PHP variables.
        $this->_URL = dirname($_SERVER['HTTP_REFERER']) . '/' .
                        basename($_SERVER['PHP_SELF'] . '/control.php');
    }

    // Startup SSVNC-Viewer in Multilisten-Mode
    $cmd = "export DISPLAY=".$display."; killall -q ssvncviewer; ssvncviewer -viewonly -multilisten 0 2>&1";
    $handle = popen($cmd, 'r');
    print("[Daemon]: vnc_viewer started");

    return $handle;
}

protected function readLog($handle) {
    print("\n[Daemon]: +++ readLog() +++");

    $halt = 0;

    // local resultset & vncclients
    $resultset = array();
    $vncclients = array();

    // local SSVNC-Client info
    $ip = "";
    $hostname = "";
    $client = array(
                    "ip" => "",
                    "hostname" => "",
                    "active" => 1,
                    "exit" => 0
                    );

    // Read File continuously
    while (!feof($handle)) {

        $buffer = fgets($handle);
        print($buffer);

        if ($this->_CONNECTIONS == 0) {
            //print("\n --- WAITING FOR NEW CONNECTIONS --- \n");
        }

        $ip = $this->parseIP($buffer);
        $hostname = $this->parseHostname($buffer);
        $exit = $this->parseExit($buffer);

        if ($ip!="") {
            $client["ip"]=$ip;
        }
        if ($hostname!="") {
            $client["hostname"]=$hostname;
        }
        if ($exit!=0) {
            $client["exit"]=$exit;
        }

        if ( strstr($buffer, 'create_image') && $client["ip"]!="" &&
            $client["hostname"]!="" ) {

            // add client
            $this->addClient($client["ip"], $client["hostname"]);

            // reset local Client information after adding it
            $client["ip"]="";
            $client["hostname"]="";
        }

        if ($exit==1) {

            // decrease active client count
            if ($this->_CONNECTIONS > 0) {
                $this->_CONNECTIONS--;
                $this->deleteInactiveVncWindow();
            }
        }

        $halt=$this->_CONNECTIONS;

        if ($halt==-1) {
            exit (0);
        }

        flush();

        }

        pclose($handle);

}

protected function parseIP($buffer) {
    $ip = "";
        $line = $buffer;
            if (strpos($line, "Reverse VNC connection from IP")) {
                $line=trim($line);
                $item=explode(":", $line);
                $ip=trim($item[1]);
                $ip=preg_replace('/\W\W\d{4}\/\d{2}\/\d{2} \d{2}/','',$ip);
            }

    if ($ip!="") {
        print("\nFOUND IP: ".$ip."\n");
    }

    return $ip;
}

protected function parseHostname($buffer) {
    $hostname = "";
        $line = $buffer;
            if(strpos($line, "Hostname")) {
                $line=trim($line);
                $item=explode(":",$line);
                $hostname=trim($item[1]);
                $hostname=preg_replace('/\.uni\-mannheim\.de/', '', $hostname);
            }

    if ($hostname!="") {
        print("\nFOUND HOSTNAME: ".$hostname."\n");
    }

    return $hostname;
}

protected function parseExit($buffer) {
    $exit = 0;
        $line = $buffer;
            if (strpos($line, "VNC Viewer exiting")) {
                $line=trim($line);
                $exit = 1;
            }

    if ($exit!=0) {
        print("\nCLIENT HAS DISCONNECTED ".$exit."\n");
    }

    return $exit;
}

protected function addClient($ip, $hostname) {

    $vncclient = array(
                        "ip" => $ip,
                        "hostname" => $hostname,
                        "active" => 1,
                        "exit" => 0
                        );
    $id = 0;
    if (count($this->_VNC_CLIENTS)==0) {
        $id=1;
    } else {
        $id=count($this->_VNC_CLIENTS)+1;
    }

    $this->_VNC_CLIENTS[$id] = $vncclient;

    print("\nCLIENT OBJECT with ID " .$id. " CREATED : "
            . $vncclient["ip"] . " | " . $vncclient["hostname"] . " | "
            . $vncclient["active"] . " | " . $vncclient["exit"] . "\n");
    print($this->_CONNECTIONS+1 . " CLIENT(S) CONNECTED ...");

    $response = $this->sendVncWindowToNuc($id, $vncclient);

    $this->_CONNECTIONS++;

    print("\n active connections: ".$this->_CONNECTIONS+1);
    print("\n all saved clients: ".serialize($this->_VNC_CLIENTS));

}

protected function sendVncWindowToNuc($id, $vncclient) {
    print("\n[Daemon]: +++sendVncWindowToNuc() +++ ");

    $vnc_id = $vncclient["hostname"] . "-" . $id;

    $db = new DBConnector();

    // already existing in db?
    $clients_in_db = array();
    $client_info = $db->getVNC_ClientInfo();

    foreach ($client_info as $info) {
        $clients_in_db[] = $info["file"];
    }

    $ip = $vncclient["ip"];
    $name = $db->querySingle('SELECT user.name
                              FROM address, user
                              WHERE user.userid = (
                                SELECT address.userid
                                FROM address
                                WHERE address.address ="'.$ip.'"
                                )'
                            );

        // print("\n[Daemon]: USERNAME : " . $name);

    $vncClientCount = $db->querySingle('SELECT count(id) FROM window WHERE handler = "vnc"');
    // $vncClientsAll = $db->query("SELECT user.name FROM address");

        // print("\n[Daemon]: clients in db = " . $vncClientCount);
        // print("\n[Daemon]: clients ignored = " . serialize($this->_IGNORE_LIST));

    // if vnc_id not in database create window and send to nuc
    if (!(in_array($vnc_id, $clients_in_db))) {

        // print("\n[Daemon]: insert $vnc_id into db");

        $dt = new DateTime();
        $date = $dt->format('Y-m-d H:i:s');

        $window = array(
            "id" => "",
            "win_id" => "",
            "name" => "",
            "state" => "",
            "file" => $name . "@" . $vnc_id,
            "handler" => "vnc",
            "userid" => $name,
            "date" => $date
            );

        $serializedWindow = serialize($window);

        $sw = urlencode($serializedWindow);
        // Get cURL resource
        $curl = curl_init();
        // Set some options - we are passing in a useragent too here
        curl_setopt_array($curl, array(
            CURLOPT_RETURNTRANSFER => 1,
            CURLOPT_URL => $this->_URL.'?newVncWindow='.$sw,
            CURLOPT_USERAGENT => 'PalMA cURL Request'
            ));
        // Send the request & save response to $resp
        $resp = curl_exec($curl);
        // Close request to clear up some resources
        curl_close($curl);

    }

    // add unique id to ignore list after sending to nuc
    array_push($this->_IGNORE_LIST, $vnc_id);

}

protected function deleteInactiveVncWindow() {
            // print("\n[Daemon]: +++ TODO: deleteInactiveWindow() +++");

        $db = new DBConnector();

        // window_ids in db
        $vnc_windows_in_db = array();
        $client_info = $db->getVNC_ClientInfo();
        foreach($client_info as $info) {
            $vnc_windows_in_db[] = $info["win_id"];
        }

        // window_ids on screen
        $windows_on_screen = array();
        $windows = explode("\n", shell_exec('wmctrl -l'));

        foreach ($windows as $w) {
            $field = explode(' ', $w);
            $id = $field[0];
            if ($id != '') {
                $windows_on_screen[] = $id;
            }
        }

            // print("[Daemon]: clients in db = " . serialize($vnc_windows_in_db));
            // print("[Daemon]: client on screen = " . serialize($windows_on_screen));

        // window_ids that are in the db, but not on the screen (window already closed)
        $inactive_vnc_window_ids = array_diff($vnc_windows_in_db, $windows_on_screen);

        foreach($inactive_vnc_window_ids as $inactive_win_id) {

            // define vnc-id
            $inactive_vnc_id = $db->querySingle("SELECT file FROM window WHERE win_id='".$inactive_win_id."'");

            // delete from database (send to control.php)
            $curl = curl_init();

            curl_setopt_array($curl, array(
                CURLOPT_RETURNTRANSFER => 1,
                CURLOPT_URL => $this->_URL.'?window=vncwin&delete=VNC&vncid='.$inactive_win_id,
                CURLOPT_USERAGENT => 'PalMA cURL Request'
                ));

            $resp = curl_exec($curl);
            curl_close($curl);

            // print("[Daemon]: inactive vnc_id = $inactive_vnc_id >> add to list: " .serialize($this->_IGNORE_LIST));

        }
}

}

$vnc = new SSVNCDaemon();

?>