# Copyright (c) 2007, Neville-Neil Consulting
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# File: $Id: $
#
# Author: George V. Neville-Neil
#
# Description: A raw data class for PCS.  This contains only data, and
# nothing else.  It is the catch all for data that is not known.

import pcs

class payload(pcs.Packet):
    """A raw data packet.

    A payload is a raw, set of bytes, and can be used to terminate any
    packet chain.  When data is not part of a packet, or the packet is
    not known this class is used to encapsulate the data."""

    layout = pcs.Layout()

    def __init__(self, bytes = None):
        """initialize a payload packet"""
        payload = pcs.Field("payload", len(bytes) * 8)
        pcs.Packet.__init__(self, [payload], bytes = bytes)
        self.description = "Data"

        # Unconditionally the last packet in a chain
        self.data = None

    def __str__(self):
        """return a readable version of a payload object"""
        retval = "%s" % self.payload