Class: Upfluence::Utils::Semaphore

Inherits:
Object
  • Object
show all
Defined in:
lib/upfluence/utils/semaphore.rb

Instance Method Summary collapse

Constructor Details

#initialize(size) ⇒ Semaphore

Returns a new instance of Semaphore.



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# File 'lib/upfluence/utils/semaphore.rb', line 4

def initialize(size)
  @size = size
  @used = 0
  @mutex = Mutex.new
  @cond = ConditionVariable.new
end

Instance Method Details

#acquire(count = 1) ⇒ Object 



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# File 'lib/upfluence/utils/semaphore.rb', line 11

def acquire(count = 1)
  @mutex.synchronize do
    loop do
      break if @used + count <= @size

      @cond.wait(@mutex)
    end

    @used += count
  end
end

#release(count = 1) ⇒ Object 



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# File 'lib/upfluence/utils/semaphore.rb', line 23

def release(count = 1)
  @mutex.synchronize do
    @used -= count
    @cond.broadcast
  end
end

#synchronize(count = 1, &block) ⇒ Object 



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# File 'lib/upfluence/utils/semaphore.rb', line 30

def synchronize(count = 1, &block)
  acquire(count)
  block.call
ensure
  release(count)
end