# This library is free software; you can redistribute it and/or
# modify it under the terms of the GNU Lesser General Public
# License as published by the Free Software Foundation; either
# version 2.1 of the License, or (at your option) any later version.
#
# This library is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
# Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public
# License along with this library; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
#
# UID.py
# Copyright (C) 2010 Simon Newton
"""The UID class."""
__author__ = 'nomis52@gmail.com (Simon Newton)'
class Error(Exception):
"""Base Error Class."""
class UIDOutOfRangeException(Error):
"""Returned when a UID would be out of range."""
class UID(object):
"""Represents a UID."""
def __init__(self, manufacturer_id, device_id):
self._manufacturer_id = manufacturer_id
self._device_id = device_id
@property
def manufacturer_id(self):
return self._manufacturer_id
@property
def device_id(self):
return self._device_id
def IsBroadcast(self):
return self._device_id == 0xffffffff
def __str__(self):
return '%04x:%08x' % (self._manufacturer_id, self._device_id)
def __hash__(self):
return hash(str(self))
def __repr__(self):
return self.__str__()
def __cmp__(self, other):
if other is None:
return 1
if self._manufacturer_id == other._manufacturer_id:
return cmp(self._device_id, other._device_id)
return cmp(self.manufacturer_id, other.manufacturer_id)
@staticmethod
def AllDevices():
return UID(0xffff, 0xffffffff)
@staticmethod
def VendorcastAddress(manufacturer_id):
return UID(manufacturer_id, 0xffffffff)
@staticmethod
def FromString(uid_str):
"""Create a new UID from a string.
Args:
uid_str: The string representation of the UID, e.g. 00f0:12345678.
"""
parts = uid_str.split(':')
if len(parts) != 2:
return None
try:
manufacturer_id = int(parts[0], 16)
device_id = int(parts[1], 16)
except ValueError:
return None
if manufacturer_id > 0xffff or device_id > 0xffffffff:
return None
return UID(manufacturer_id, device_id)
@staticmethod
def NextUID(uid):
if uid == UID.AllDevices():
raise UIDOutOfRangeException(uid)
if uid.IsBroadcast():
return UID(uid.manufacturer_id + 1, 0)
else:
return UID(uid.manufacturer_id, uid.device_id + 1)
@staticmethod
def PreviousUID(uid):
if uid == UID(0, 0):
raise UIDOutOfRangeException(uid)
if uid.device_id == 0:
return UID(uid.manufacturer_id - 1, 0xffffffff)
else:
return UID(uid.manufacturer_id, uid.device_id - 1)