Class: Origami::Reference

Inherits:
Object
  • Object
show all
Includes:
Comparable, Object
Defined in:
lib/origami/reference.rb,
lib/origami/obfuscation.rb

Overview

Class representing a Reference Object. Reference are like symbolic links pointing to a particular object into the file.

Constant Summary collapse

TOKENS =

:nodoc:

["(?<no>\\d+)" + WHITESPACES + "(?<gen>\\d+)" + WHITESPACES + "R"]
REGEXP_TOKEN = 
Regexp.new(TOKENS.first, Regexp::MULTILINE)
@@regexp = 
Regexp.new(WHITESPACES + TOKENS.first + WHITESPACES)

Instance Attribute Summary collapse

Attributes included from Object

#file_offset, #generation, #no, #objstm_offset, #parent

Class Method Summary collapse

Instance Method Summary collapse

Methods included from Object

#cast_to, #copy, #document, #export, included, #indirect?, #indirect_parent, #logicalize, #logicalize!, #native_type, #numbered?, #post_build, #pre_build, #reference, #set_document, #set_indirect, skip_until_next_obj, #to_o, #type, typeof, #version_required, #xrefs

Constructor Details

#initialize(refno, refgen) ⇒ Reference

Returns a new instance of Reference.



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# File 'lib/origami/reference.rb', line 39

def initialize(refno, refgen)
  super()

  @refno, @refgen = refno, refgen
end

Instance Attribute Details

#refgen ⇒ Object

Returns the value of attribute refgen.



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# File 'lib/origami/reference.rb', line 37

def refgen
  @refgen
end

#refno ⇒ Object

Returns the value of attribute refno.



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# File 'lib/origami/reference.rb', line 37

def refno
  @refno
end

Class Method Details

.parse(stream, _parser = nil) ⇒ Object

:nodoc:



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# File 'lib/origami/reference.rb', line 45

def self.parse(stream, _parser = nil) # :nodoc:
  scanner = Parser.init_scanner(stream)
  offset = scanner.pos

  if scanner.scan(@@regexp).nil?
    raise InvalidReferenceError, "Bad reference to indirect objet format"
  end

  no = scanner['no'].to_i
  gen = scanner['gen'].to_i

  ref = Reference.new(no, gen)
  ref.file_offset = offset

  ref
end

Instance Method Details

#<=>(other) ⇒ Object

:nodoc



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# File 'lib/origami/reference.rb', line 98

def <=>(other) # :nodoc
  to_a <=> other.to_a
end

#==(other) ⇒ Object Also known as: eql?

Compares to Reference object.



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# File 'lib/origami/reference.rb', line 105

def ==(other)
  return false unless other.is_a?(Reference)

  to_a == other.to_a
end

#follow ⇒ Object Also known as: solve

Returns the object pointed to by the reference. The reference must be part of a document. Raises an InvalidReferenceError if the object cannot be found.



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# File 'lib/origami/reference.rb', line 67

def follow
  doc = document

  if doc.nil?
    raise InvalidReferenceError, "Not attached to any document"
  end

  target = doc.get_object(self)

  if target.nil? && !Origami::OPTIONS[:ignore_bad_references]
    raise InvalidReferenceError, "Cannot resolve reference : #{self}"
  end

  target or Null.new
end

#hash ⇒ Object

:nodoc:



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# File 'lib/origami/reference.rb', line 94

def hash # :nodoc:
  to_a.hash
end

#to_a ⇒ Object

Returns a Ruby array with the object number and the generation this reference is pointing to.



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# File 'lib/origami/reference.rb', line 115

def to_a
  [@refno, @refgen]
end

#to_obfuscated_str ⇒ Object 



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# File 'lib/origami/obfuscation.rb', line 182

def to_obfuscated_str
  refstr = refno.to_s + Obfuscator.junk_spaces + refgen.to_s + Obfuscator.junk_spaces + "R"

  super(refstr)
end

#to_s(eol: $/) ⇒ Object

:nodoc:



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# File 'lib/origami/reference.rb', line 119

def to_s(eol: $/) # :nodoc:
  super("#{@refno} #{@refgen} R", eol: eol)
end

#valid? ⇒ Boolean

Returns true if the reference points to an object.

Returns:



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# File 'lib/origami/reference.rb', line 87

def valid?
  solve
  true
rescue InvalidReferenceError
  false
end

#value ⇒ Object

Returns the referenced object value.



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# File 'lib/origami/reference.rb', line 126

def value
  solve.value
end