functions.php

<?php

function do_xmlrpc($request) {
  global $scgi_host, $scgi_port, $scgi_timeout;
  if($response = scgi_send($scgi_host, $scgi_port, $request, $scgi_timeout)) {
    $response = parse_http_response($response);
    $content = str_replace('i8', 'double', $response[1]);
    return xmlrpc_decode(utf8_encode($content));
  } else {
    die('<h1>ERROR: Cannot connect to rtorrent</h1>');
  }
}

// ... snip other functions ...

function parse_http_response($string) {
  $headers = array();
  $arr = explode("\n", $string);
  for($i = 0; $i < count($arr); $i++) {
    $str = trim($arr[$i]);
    if($str === '') {
      return array($headers, implode("\n", array_slice($arr, $i + 1)));
    } else {
      list($name, $val) = explode(':', $str, 2);
      $name = strtolower($name);
      $val = ltrim($val);
      if(is_array($headers[$name])) {
        $headers[$name][] = $val;
      } else if(isset($headers[$name])) {
        $headers[$name] = array($headers[$name], $val);
      } else {
        $headers[$name] = $val;
      }
    }
  }
  return array($headers, '');
}

// from source code of rutorrent
function scgi_send($host, $port, $data, $timeout=5) {
  $result = '';
  $contentlength = strlen($data);
  if($contentlength > 0) {
    $socket = @fsockopen($host, $port, $errno, $errstr, $timeout);
    if($socket) {
      $reqheader = "CONTENT_LENGTH\x00$contentlength\x00SCGI\x001\x00";
      $tosend = strlen($reqheader) . ":$reqheader,$data";
      @fputs($socket, $tosend);
      while(!feof($socket)) {
        $result .= @fread($socket, 4096);
      }
      fclose($socket);
    }
  }
  return $result;
}

?>

Full file is located at http://github.com/nylen/rtgui/blob/master/functions.php