Class: Datadog::Core::Remote::Component::Barrier

Inherits:
Object
  • Object
show all
Defined in:
lib/datadog/core/remote/component.rb

Overview

Barrier provides a mechanism to fence execution until a condition happens

Instance Method Summary collapse

Constructor Details

#initialize(timeout = nil) ⇒ Barrier

Returns a new instance of Barrier.



63
64
65
66
67
68
69
 
# File 'lib/datadog/core/remote/component.rb', line 63

def initialize(timeout = nil)
  @once = false
  @timeout = timeout

  @mutex = Mutex.new
  @condition = ConditionVariable.new
end

Instance Method Details

#lift ⇒ Object

Release all current waiters



104
105
106
107
108
109
110
111
112
 
# File 'lib/datadog/core/remote/component.rb', line 104

def lift
  @mutex.lock

  @once ||= true

  @condition.broadcast
ensure
  @mutex.unlock
end

#wait_next(timeout = nil) ⇒ Object

Wait for next lift to happen



92
93
94
95
96
97
98
99
100
101
 
# File 'lib/datadog/core/remote/component.rb', line 92

def wait_next(timeout = nil)
  @mutex.lock

  timeout ||= @timeout

  # rbs/core has a bug, timeout type is incorrectly ?Integer
  @condition.wait(@mutex, _ = timeout)
ensure
  @mutex.unlock
end

#wait_once(timeout = nil) ⇒ Object

Wait for first lift to happen, otherwise don’t wait



72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
 
# File 'lib/datadog/core/remote/component.rb', line 72

def wait_once(timeout = nil)
  # TTAS (Test and Test-And-Set) optimisation
  # Since @once only ever goes from false to true, this is semantically valid
  return if @once

  begin
    @mutex.lock

    return if @once

    timeout ||= @timeout

    # rbs/core has a bug, timeout type is incorrectly ?Integer
    @condition.wait(@mutex, _ = timeout)
  ensure
    @mutex.unlock
  end
end