Class: Ori::Semaphore

Inherits:
Object
  • Object
show all
Includes:
Selectable
Defined in:
lib/ori/semaphore.rb

Direct Known Subclasses

Mutex

Instance Method Summary collapse

Constructor Details

#initialize(num_tickets) ⇒ Semaphore

Returns a new instance of Semaphore.

Raises:

  • (ArgumentError) 


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# File 'lib/ori/semaphore.rb', line 7

def initialize(num_tickets)
  raise ArgumentError, "Number of tickets must be positive" if num_tickets <= 0

  @tickets = num_tickets
  @available = num_tickets
end

Instance Method Details

#acquire ⇒ Object 



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# File 'lib/ori/semaphore.rb', line 30

def acquire
  Fiber.yield(self) until available?
  @available -= 1
  true
end

#available? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/ori/semaphore.rb', line 36

def available?
  @available > 0
end

#await ⇒ Object 



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# File 'lib/ori/semaphore.rb', line 44

def await
  Fiber.yield until available?
  true
end

#count ⇒ Object 



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# File 'lib/ori/semaphore.rb', line 40

def count
  @available
end

#release ⇒ Object 



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# File 'lib/ori/semaphore.rb', line 23

def release
  raise "Semaphore overflow" if @available >= @tickets

  @available += 1
  true
end

#sync ⇒ Object 



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# File 'lib/ori/semaphore.rb', line 14

def sync
  acquire
  begin
    yield
  ensure
    release
  end
end