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 class Rainbows::DevFdResponse < Struct.new(:app)
13 FD_MAP = Rainbows::FD_MAP
14 Content_Length = "Content-Length".freeze
15 Transfer_Encoding = "Transfer-Encoding".freeze
16 Rainbows_autochunk = "rainbows.autochunk".freeze
17 Rainbows_model = "rainbows.model"
18 HTTP_VERSION = "HTTP_VERSION"
22 # Rack middleware entry point, we'll just pass through responses
23 # unless they respond to +to_io+ or +to_path+
25 status, headers, body = response = app.call(env)
27 # totally uninteresting to us if there's no body
28 if STATUS_WITH_NO_ENTITY_BODY.include?(status.to_i) ||
30 (body.respond_to?(:to_path) && File.file?(body.to_path))
34 io = body.to_io if body.respond_to?(:to_io)
35 io ||= File.open(body.to_path) if body.respond_to?(:to_path)
36 return response if io.nil?
38 headers = Rack::Utils::HeaderHash.new(headers) unless Hash === headers
43 headers[Content_Length] ||= st.size.to_s
44 headers.delete(Transfer_Encoding)
45 elsif st.pipe? || st.socket? # epoll-able things
46 unless headers.include?(Content_Length)
47 if env[Rainbows_autochunk]
48 case env[HTTP_VERSION]
51 headers[Transfer_Encoding] = Chunked
54 env[Rainbows_autochunk] = false
58 # we need to make sure our pipe output is Fiber-compatible
59 case env[Rainbows_model]
60 when :FiberSpawn, :FiberPool, :RevFiberSpawn, :CoolioFiberSpawn
61 io.respond_to?(:kgio_wait_readable) or
62 io = Rainbows::Fiber::IO.new(io)
64 io = Rainbows::Revactor::Proxy.new(io)
66 else # unlikely, char/block device file, directory, ...
69 [ status, headers, Body.new(io, "/dev/fd/#{fileno}", body) ]
72 class Body < Struct.new(:to_io, :to_path, :orig_body) # :nodoc:
73 # called by the webserver or other middlewares if they can't
76 to_io.each { |x| yield x }
79 # remain Rack::Lint-compatible for people with wonky systems :P
80 unless File.directory?("/dev/fd")
81 alias to_path_orig to_path
85 # called by the web server after #each
87 to_io.close unless to_io.closed?
88 orig_body.close if orig_body.respond_to?(:close) # may not be an IO
89 rescue IOError # could've been IO::new()'ed and closed