Rack::ContentLength

# File lib/rack/content_length.rb, line 10
def initialize(app)
  @app = app
end

# File lib/rack/content_length.rb, line 14
def call(env)
  status, headers, body = @app.call(env)
  headers = HeaderHash.new(headers)

  if !STATUS_WITH_NO_ENTITY_BODY.include?(status.to_i) &&
     !headers[CONTENT_LENGTH] &&
     !headers['Transfer-Encoding'] &&
     body.respond_to?(:to_ary)

    obody = body
    body, length = [], 0
    obody.each { |part| body << part; length += bytesize(part) }

    body = BodyProxy.new(body) do
      obody.close if obody.respond_to?(:close)
    end

    headers[CONTENT_LENGTH] = length.to_s
  end

  [status, headers, body]
end