module Rack::Multipart

def parse_multipart(env, params = Rack::Utils.default_query_parser)
  io = env[RACK_INPUT]
  if content_length = env['CONTENT_LENGTH']
    content_length = content_length.to_i
  end
  content_type = env['CONTENT_TYPE']
  tempfile = env[RACK_MULTIPART_TEMPFILE_FACTORY] || Parser::TEMPFILE_FACTORY
  bufsize = env[RACK_MULTIPART_BUFFER_SIZE] || Parser::BUFSIZE
  info = Parser.parse(io, content_length, content_type, tempfile, bufsize, params)
  env[RACK_TEMPFILES] = info.tmp_files
  return info.params
end