function http_request($url, $method = 'GET', $postfields = NULL, $headers = array()) {

 

    $parse = parse_url($url);

 

    isset($parse['host']) ||$parse['host'] = '';

    isset($parse['path']) || $parse['path'] = '';

    isset($parse['query']) || $parse['query'] = '';

    isset($parse['port']) || $parse['port'] = '';

 

    $path = $parse['path'] ? $parse['path'].($parse['query'] ? '?'.$parse['query'] : '') : '/';

    $host = $parse['host'];

 

    //协议

    if ($parse['scheme'] == 'https') {

        $version = '1.1';

        $port = empty($parse['port']) ? 443 : $parse['port'];

        $host = 'ssl://'.$host;

    } else {

        $version = '1.0';

        $port = empty($parse['port']) ? 80 : $parse['port'];

    }

 

    //Headers

    $headers[] = "Host: {$parse['host']}";

    $headers[] = 'Connection: Close';

    $headers[] = "User-Agent: $_SERVER[HTTP_USER_AGENT]";

    $headers[] = 'Accept: */*';

 

    //包体信息

    if ($method == 'POST') {

        if(is_array($postfields)){

            $postfields = http_build_query($postfields);

        }

        $headers[] = "Content-type: application/x-www-form-urlencoded";

        $headers[] = 'Content-Length: '.strlen($postfields);

        $out = "POST $path HTTP/$version\r\n".join("\r\n", $headers)."\r\n\r\n".$postfields;

    } else {

        $out = "GET $path HTTP/$version\r\n".join("\r\n", $headers)."\r\n\r\n";

    }

 

    //发送请求

    $limit = 0;

    $fp = fsockopen($host, $port, $errno, $errstr, 30);

 

    if (!$fp) {

        exit('Failed to establish socket connection: '.$url);

    } else {

        $header = $content = '';

        //集阻塞/非阻塞模式流,$block==true则应用流模式

        stream_set_blocking($fp, true);

         //设置流的超时时间

        stream_set_timeout($fp, 30);

        fwrite($fp, $out);

        //从封装协议文件指针中取得报头／元数据

        $status = stream_get_meta_data($fp);

 

        if (!$status['timed_out']) { //未超时

            while (!feof($fp)) {

                $header .= $h = fgets($fp);

                if ($h && ($h == "\r\n" ||  $h == "\n")) break;

                if (strpos($h, 'Content-Length:') !== false) {

                    $limit = intval(substr($header, 15));

                }

            }

 

            $stop = false;

            while (!feof($fp) && !$stop) {

                $data = fread($fp, ($limit == 0 || $limit > 8192 ? 8192 : $limit));

                $content .= $data;

                if ($limit) {

                    $limit -= strlen($data);

                    $stop = $limit <= 0;

                }

            }

        }

        fclose($fp);

 

        //unchunk

        $content = preg_replace_callback(

            '/(?:(?:\r\n|\n)|^)([0-9A-F]+)(?:\r\n|\n){1,2}(.*?)'.

            '((?:\r\n|\n)(?:[0-9A-F]+(?:\r\n|\n))|$)/si',

            create_function(

                '$matches',

                'return hexdec($matches[1]) == strlen($matches[2]) ? $matches[2] : $matches[0];'

            ),

            $content

        );

 

        return $content;

    }

}

ignore_user_abort(TRUE);//如果客户端断开连接，不会引起脚本abort

set_time_limit(0);//取消脚本执行延时上限