Class: Bitcoin::BitStreamReader

Inherits:
Object
  • Object
show all
Defined in:
lib/bitcoin/bit_stream.rb

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(payload) ⇒ BitStreamReader

Returns a new instance of BitStreamReader.



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# File 'lib/bitcoin/bit_stream.rb', line 44

def initialize(payload)
  @offset = 8
  @buffer = 0
  @stream = StringIO.new(payload)
end

Instance Attribute Details

#buffer ⇒ Object

Returns the value of attribute buffer.



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# File 'lib/bitcoin/bit_stream.rb', line 41

def buffer
  @buffer
end

#offset ⇒ Object

Returns the value of attribute offset.



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# File 'lib/bitcoin/bit_stream.rb', line 42

def offset
  @offset
end

#stream ⇒ Object (readonly)

Returns the value of attribute stream.



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# File 'lib/bitcoin/bit_stream.rb', line 40

def stream
  @stream
end

Instance Method Details

#read(nbits) ⇒ Object

offset



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# File 'lib/bitcoin/bit_stream.rb', line 51

def read(nbits)
  raise 'nbits must be between 0 and 64' if nbits < 0 || nbits > 64
  data = 0
  while nbits > 0
    if offset == 8
      raise IOError, 'stream is empty.' if stream.eof?
      self.buffer = stream.read(1).bth.to_i(16)
      self.offset = 0
    end
    bits = [8 - offset, nbits].min
    data <<= bits
    tmp = (buffer << offset) & 255
    data = data | (tmp >> (8 - bits))
    self.offset += bits
    nbits -= bits
  end
  data
end