Method: CoRE::CoAP::Message.parse

Defined in:

lib/core/coap/message.rb

.parse(d) ⇒ Object

Raises:

• (ArgumentError)

# File 'lib/core/coap/message.rb', line 159

def self.parse(d)
  # dpos keeps our current position in parsing d
  b1, mcode, mid = d.unpack("CCn"); dpos = 4
  toklen = b1 & 0xf
  token = d.byteslice(dpos, toklen); dpos += toklen
  b1 >>= 4
  tt = TTYPES[b1 & 0x3]
  b1 >>= 2
  raise ArgumentError, "unknown CoAP version #{b1}" unless b1 == 1
  mcode = METHODS[mcode] || [mcode>>5, mcode&0x1F]

  # collect options
  onumber = 0             # current option number
  options = Hash.new { |h, k| h[k] = [] }
  dlen = d.bytesize
  while dpos < dlen
    tl1 = d.getbyte(dpos); dpos += 1
    raise ArgumentError, "option is not there at #{dpos} with oc #{orig_numopt}" unless tl1 # XXX

    break if tl1 == 0xff

    odelta, dpos = deklausify(d, dpos, tl1 >> 4)
    olen, dpos = deklausify(d, dpos, tl1 & 0xF)

    onumber += odelta

    if dpos + olen > dlen
      raise ArgumentError, "#{olen}-byte option at #{dpos} -- not enough data in #{dlen} total"
    end

    oval = d.byteslice(dpos, olen); dpos += olen
    options[onumber] << oval
  end

  options[CoAP::TOKEN_ON] = [token] if token != ''
  
  # d.bytesize = more than all the rest...
  decode_options_and_put_together(b1, tt, mcode, mid, options,
                                  d.byteslice(dpos, d.bytesize))
end