PHP实现的CURL非阻塞调用类

/*****************************************************
 CURL 非阻塞调用类
 Auther: Linvo
 Copyright(C) 2010/10/21
*******************************************************/
/*
  // 使用范例
  // 传入参数说明
  // url 请求地址
  // data POST方式数据
  //并发调用
  $param1 = array(
      array(
        'url' => "http://localhost/a.php?s=1",
        ),
      array(
        'url' => "http://localhost/a.php?s=1",
        'data' => array('aaa' => 1, 'bbb' => 2),
        ),
      );
  //单个调用
  $param2 = array(
      'url' => "http://localhost/a.php?s=0",
      'data' => array('aaa' => 1, 'bbb' => 2),
      );
  //单个调用（GET简便方式）
  $param3 = 'http://localhost/a.php?s=2';
  $ac = new AsyncCURL();
  $ac->set_param($param1);
  $ret = $ac->send();
  //返回值为请求参数顺序的结果数组（元素值为False表示请求错误）
  var_dump($ret);
*/
class AsyncCURL
{
  /**
   * 是否需要返回HTTP头信息
   */
  public $curlopt_header = 0;
  /**
   * 单个CURL调用超时限制
   */
  public $curlopt_timeout = 20;
  private $param = array();
  /**
   * 构造函数（可直接传入请求参数）
   *
   * @param array 可选
   * @return void
   */
  public function __construct($param = False)
  {
    if ($param !== False)
    {
      $this->param = $this->init_param($param);
    }
  }
  /**
   * 设置请求参数
   *
   * @param array
   * @return void
   */
  public function set_param($param)
  {
    $this->param = $this->init_param($param);
  }
  /**
   * 发送请求
   *
   * @return array
   */
  public function send()
  {
    if(!is_array($this->param) || !count($this->param))
    {
      return False;
    }
    $curl = $ret = array();
    $handle = curl_multi_init();
    foreach ($this->param as $k => $v)
    {
      $param = $this->check_param($v);
      if (!$param) $curl[$k] = False;
      else $curl[$k] = $this->add_handle($handle, $param);
    }
    $this->exec_handle($handle);
    foreach ($this->param as $k => $v)
    {
      if ($curl[$k])
      {
        $ret[$k] = curl_multi_getcontent($curl[$k]);
        curl_multi_remove_handle($handle, $curl[$k]);
      } else {
        $ret[$k] = False;
      }
    }
    curl_multi_close($handle);
    return $ret;
  }
  //以下为私有方法
  private function init_param($param)
  {
    $ret = False;
    if (isset($param['url']))
    {
      $ret = array($param);
    } else {
      $ret = isset($param[0]) ? $param : False;
    }
    return $ret;
  }
  private function check_param($param = array())
  {
    $ret = array();
    if (is_string($param))
    {
      $url = $param;
    } else {
      extract($param);
    }
    if (isset($url))
    {
      $url = trim($url);
      $url = stripos($url, 'http://') === 0 ? $url : NULL;
    }
    if (isset($data) && is_array($data) && !empty($data))
    {
      $method = 'POST';
    } else {
      $method = 'GET';
      unset($data);
    }
    if (isset($url)) $ret['url'] = $url;
    if (isset($method)) $ret['method'] = $method;
    if (isset($data)) $ret['data'] = $data;
    $ret = isset($url) ? $ret : False;
    return $ret;
  }
  private function add_handle($handle, $param)
  {
    $curl = curl_init();
    curl_setopt($curl, CURLOPT_URL, $param['url']);
    curl_setopt($curl, CURLOPT_HEADER, $this->curlopt_header);
    curl_setopt($curl, CURLOPT_RETURNTRANSFER, 1);
    curl_setopt($curl, CURLOPT_TIMEOUT, $this->curlopt_timeout);
    if ($param['method'] == 'POST')
    {
      curl_setopt($curl, CURLOPT_POST, 1);
      curl_setopt($curl, CURLOPT_POSTFIELDS, $param['data']);
    }
    curl_multi_add_handle($handle, $curl);
    return $curl;
  }
  private function exec_handle($handle)
  {
    $flag = null;
    do {
      curl_multi_exec($handle, $flag);
    } while ($flag > 0);
  }
}