修 CI v1.7.1 的檔案上傳問題

/**
 * Verify that the filetype is allowed
 *
 * @access  public
 * @return  bool
 */ 
function is_allowed_filetype()
{
  if (count($this->allowed_types) == 0 OR ! is_array($this->allowed_types))
  {
    $this->set_error('upload_no_file_types');
    return FALSE;
  }

  $image_types = array('gif', 'jpg', 'jpeg', 'png', 'jpe');

  foreach ($this->allowed_types as $val)
  {
    $mime = $this->mimes_types(strtolower($val));
  
    // Images get some additional checks
    //if (in_array($val, $image_types))

    //FIXED: 僅上傳的檔案為圖檔時，才做圖檔大小的判斷
    if (in_array($val, $image_types) && $val == str_replace(".","",$this->file_ext))
    {
      if (getimagesize($this->file_temp) === FALSE)
      {
        return FALSE;
      }
    }

    if (is_array($mime))
    {
      if (in_array($this->file_type, $mime, TRUE))
      {
        return TRUE;
      }
    }
    else
    {
      if ($mime == $this->file_type)
      {
        return TRUE;
      } 
    }   
  }
  
  return FALSE;
}