Module: Rex::Ref

Defined in:
lib/rex/sync/ref.rb

Overview

This module provides a uniform reference counted interface for classes to use.

Class Method Summary collapse

Instance Method Summary collapse

Class Method Details

.extended(instance) ⇒ Object

Ensures that the Ref is correctly initialized when extended on an object: “‘ arbitrary_resource = Resource.new arbitrary_resource.extend(::Rex::Ref) “`

Parameters:

  • instance (object) —

    the instance that has just extended the Ref module



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# File 'lib/rex/sync/ref.rb', line 35

def self.extended(instance)
  instance.refinit
end

Instance Method Details

#cleanup ⇒ Object

Called to clean up resources once the ref count drops to zero.



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# File 'lib/rex/sync/ref.rb', line 81

def cleanup
end

#clone ⇒ Object

Raises a TypeError to prevent cloning.

Raises:

  • (TypeError) 


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# File 'lib/rex/sync/ref.rb', line 16

def clone
  raise TypeError, "can't clone instance of Ref #{self.class}"
end

#deref ⇒ Object

Decrements the total number of references. If the reference count reaches zero, true is returned. Otherwise, false is returned.



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# File 'lib/rex/sync/ref.rb', line 66

def deref
  @_references_mutex.synchronize {
    if ((@_references -= 1) == 0)
      cleanup

      true
    else
      false
    end
  }
end

#dup ⇒ Object

Raises a TypeError to prevent duping.

Raises:

  • (TypeError) 


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# File 'lib/rex/sync/ref.rb', line 23

def dup
  raise TypeError, "can't dup instance of Ref #{self.class}"
end

#ref ⇒ Object

Increments the total number of references.



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# File 'lib/rex/sync/ref.rb', line 54

def ref
  @_references_mutex.synchronize {
    @_references += 1
  }

  self
end

#refinit ⇒ Object

Initializes the reference count to one.



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# File 'lib/rex/sync/ref.rb', line 42

def refinit
  return if defined?(@_references)

  @_references       = 1
  @_references_mutex = Mutex.new

  self
end