1 # -*- encoding: binary -*-
3 # Rack response middleware wrapping any IO-like object with an
4 # OS-level file descriptor associated with it. May also be used to
5 # create responses from integer file descriptors or existing +IO+
6 # objects. This may be used in conjunction with the #to_path method
7 # on servers that support it to pass arbitrary file descriptors into
8 # the HTTP response without additional open(2) syscalls
10 # This middleware is currently a no-op for Rubinius, as it lacks
11 # IO.copy_stream in 1.9 and also due to a bug here:
12 # http://github.com/evanphx/rubinius/issues/379
14 class Rainbows::DevFdResponse < Struct.new(:app)
17 FD_MAP = Rainbows::FD_MAP
18 Content_Length = "Content-Length".freeze
19 Transfer_Encoding = "Transfer-Encoding".freeze
20 Rainbows_autochunk = "rainbows.autochunk".freeze
21 Rainbows_model = "rainbows.model"
22 HTTP_VERSION = "HTTP_VERSION"
25 # make this a no-op under Rubinius, it's pointless anyways
26 # since Rubinius doesn't have IO.copy_stream
29 end if defined?(RUBY_ENGINE) && RUBY_ENGINE == 'rbx'
32 # Rack middleware entry point, we'll just pass through responses
33 # unless they respond to +to_io+ or +to_path+
35 status, headers, body = response = app.call(env)
37 # totally uninteresting to us if there's no body
38 if STATUS_WITH_NO_ENTITY_BODY.include?(status.to_i) ||
40 (body.respond_to?(:to_path) && File.file?(body.to_path))
44 io = body.to_io if body.respond_to?(:to_io)
45 io ||= File.open(body.to_path) if body.respond_to?(:to_path)
46 return response if io.nil?
48 headers = Rack::Utils::HeaderHash.new(headers) unless Hash === headers
53 headers[Content_Length] ||= st.size.to_s
54 headers.delete(Transfer_Encoding)
55 elsif st.pipe? || st.socket? # epoll-able things
56 unless headers.include?(Content_Length)
57 if env[Rainbows_autochunk]
58 case env[HTTP_VERSION]
61 headers[Transfer_Encoding] = Chunked
64 env[Rainbows_autochunk] = false
68 # we need to make sure our pipe output is Fiber-compatible
69 case env[Rainbows_model]
70 when :FiberSpawn, :FiberPool, :RevFiberSpawn, :CoolioFiberSpawn
71 io.respond_to?(:kgio_wait_readable) or
72 io = Rainbows::Fiber::IO.new(io)
74 io = Rainbows::Revactor::Proxy.new(io)
76 else # unlikely, char/block device file, directory, ...
79 [ status, headers, Body.new(io, "/dev/fd/#{fileno}", body) ]
82 class Body < Struct.new(:to_io, :to_path, :orig_body)
83 # called by the webserver or other middlewares if they can't
86 to_io.each { |x| yield x }
89 # remain Rack::Lint-compatible for people with wonky systems :P
90 unless File.directory?("/dev/fd")
91 alias to_path_orig to_path
95 # called by the web server after #each
97 to_io.close unless to_io.closed?
98 orig_body.close if orig_body.respond_to?(:close) # may not be an IO
99 rescue IOError # could've been IO::new()'ed and closed