Module: FiberScheduler::Compatibility

Defined in:
lib/fiber_scheduler/compatibility.rb

Class Method Summary collapse

Instance Method Summary collapse

Class Method Details

.internal? ⇒ Boolean

Returns:

  • (Boolean) 


60
61
62
 
# File 'lib/fiber_scheduler/compatibility.rb', line 60

def self.internal?
  Thread.current[:_fiber_scheduler]
end

.set_internal! ⇒ Object 



56
57
58
 
# File 'lib/fiber_scheduler/compatibility.rb', line 56

def self.set_internal!
  Thread.current[:_fiber_scheduler] = true # Sets a FIBER local var!
end

Instance Method Details

#fiber(*args, **opts, &block) ⇒ Object 



3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
 
# File 'lib/fiber_scheduler/compatibility.rb', line 3

def fiber(*args, **opts, &block)
  return super unless Compatibility.internal?

  # This is `Fiber.schedule` call inside `FiberScheduler { ... }` block.
  type = args.first
  case type
  when :blocking
    Fiber.new(blocking: true) {
      Compatibility.set_internal!
      yield
    }.tap(&:resume)

  when :waiting
    parent = Fiber.current
    finished = false # prevents races
    blocking = false # prevents #unblock-ing a fiber that never blocked

    # Don't pass *args and **opts to an unknown fiber scheduler class.
    super() do
      Compatibility.set_internal!
      yield
    ensure
      finished = true
      unblock(nil, parent) if blocking
    end

    unless finished
      blocking = true
      block(nil, nil)
    end

  when :fleeting
    # Transfer to current fiber some time - after a fleeting fiber yields.
    unblock(nil, Fiber.current)
    # Alternative to #unblock: Fiber.scheduler.push(Fiber.current)

    Fiber.new(blocking: false) {
      Compatibility.set_internal!
      yield
    }.transfer

  when nil
    # Don't pass *args and **opts to an unknown fiber scheduler class.
    super() do
      Compatibility.set_internal!
      yield
    end

  else
    raise "Unknown type"
  end
end