Module: Mycel::Framing

Defined in:
lib/mycel.rb

Overview

Layer 1: Framing — length-prefixed chunks (up to 1,073,741,823 bytes)

Class Method Summary collapse

Instance Method Summary collapse

Class Method Details

.read(io) ⇒ Object

Raises:

  • (EOFError) 


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# File 'lib/mycel.rb', line 83

def self.read(io)
  raise EOFError unless (t1 = io.read(1))
  if ((w = ((t2 = t1.unpack('C')[0]) & 0xC0) >> 6) == 0)
    t3 = 0
  else
    raise EOFError unless (t1 = io.read(w))
    t3 = t1.rjust(4, "\x00").unpack('N')[0]
  end
  io.read(t3 | (t2 & 0x3F) << (w * 8))
end

.write(io, msg) ⇒ Object

Raises:

  • (ArgumentError) 


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# File 'lib/mycel.rb', line 94

def self.write(io, msg)
  begin
    msg = msg.to_s.force_encoding("ASCII-8BIT")
  rescue NoMethodError
    msg = msg.to_s
  end
  raise(ArgumentError) if (l = msg.length) >= 0xC0000000
  w = ((l & 0x3FFFC000 == 0) ?
    ((l & 0x00003FC0 == 0) ? 0 : 1) :
    ((l & 0x3FC00000 == 0) ? 2 : 3))
  h = Array.new
  w.downto(0) do |i|
    h.push 0xff & (l >> (i * 8))
  end
  h[0] = h[0] | w << 6
  io.print h.pack('C*'), msg
end

Instance Method Details

#read_chunk ⇒ Object 



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# File 'lib/mycel.rb', line 112

def read_chunk
  Mycel::Framing.read(self)
end

#write_chunk(msg) ⇒ Object 



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# File 'lib/mycel.rb', line 116

def write_chunk(msg)
  Mycel::Framing.write(self, msg)
end