Class: OsCtld::Manipulable::ManipulationLock

Inherits:
Object
  • Object
show all
Defined in:
lib/osctld/manipulable.rb

Instance Method Summary collapse

Constructor Details

#initialize ⇒ ManipulationLock

Returns a new instance of ManipulationLock.



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# File 'lib/osctld/manipulable.rb', line 21

def initialize
  @hold = Mutex.new
  @meta = Mutex.new
end

Instance Method Details

#acquire(resource, by, block: false, &codeblock) ⇒ Object 



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# File 'lib/osctld/manipulable.rb', line 26

def acquire(resource, by, block: false, &codeblock)
  if @hold.owned?
    # This thread already holds the lock, just call the block or return,
    # do not release the hold.
    return true unless codeblock

    codeblock.call

  elsif block
    # Get the lock, wait if necessary and release it when done
    @hold.lock
    self.holder = by

    return true unless codeblock

    run_block(&codeblock)

  elsif @hold.try_lock
    # Try to get the hold, but do not wait if it isn't available
    self.holder = by

    return true unless block_given?

    run_block(&codeblock)

  else
    raise ResourceLocked.new(resource, holder)
  end
end

#holder ⇒ Object 



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# File 'lib/osctld/manipulable.rb', line 65

def holder
  @meta.synchronize { @holder }
end

#holder=(v) ⇒ Object (protected) 



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# File 'lib/osctld/manipulable.rb', line 71

def holder=(v)
  @meta.synchronize { @holder = v }
end

#locked? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/osctld/manipulable.rb', line 61

def locked?
  @hold.locked?
end

#release ⇒ Object 



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# File 'lib/osctld/manipulable.rb', line 56

def release
  @hold.unlock
  self.holder = nil
end

#run_block ⇒ Object (protected) 



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# File 'lib/osctld/manipulable.rb', line 75

def run_block
  yield
ensure
  @hold.unlock if @hold.owned?
  self.holder = nil
end