THINKPHP 部署nginx上URL 构造错误

if(!IS_CLI) {
    // 当前文件名
    if(!defined('_PHP_FILE_')) {
        if(IS_CGI) {
            //CGI/FASTCGI模式下
            $_temp  = explode('.php',$_SERVER['PHP_SELF']);
            define('_PHP_FILE_',    rtrim(str_replace($_SERVER['HTTP_HOST'],'',$_temp[0].'.php'),'/'));
        }else {
            define('_PHP_FILE_',    rtrim($_SERVER['SCRIPT_NAME'],'/'));
        }
    }
    if(!defined('__ROOT__')) {
        $_root  =   rtrim(dirname(_PHP_FILE_),'/');
        define('__ROOT__',  (($_root=='/' || $_root=='\')?'':$_root));
    }
}