gistfile1.rb

    # Take the basename of the upload's original filename.
    # This handles the full Windows paths given by Internet Explorer
    # (and perhaps other broken user agents) without affecting
    # those which give the lone filename.
    # The Windows regexp is adapted from Perl's File::Basename.
    def original_filename
      unless defined? @original_filename
        @original_filename =
          unless original_path.blank?
            if original_path =~ /^(?:.*[:\\\/])?(.*)/m
              $1
            else
              File.basename original_path
            end
          end
      end
      @original_filename
    end