Alexander Afanasyev | 5ba9036 | 2013-07-15 19:58:38 -0700 | [diff] [blame] | 1 | ## -*- Mode: python; py-indent-offset: 4; indent-tabs-mode: nil; coding: utf-8; -*- |
| 2 | # |
| 3 | # Copyright (c) 2011-2013, Regents of the University of California |
| 4 | # Alexander Afanasyev |
| 5 | # |
| 6 | # GNU 3.0 license, See the LICENSE file for more information |
| 7 | # |
| 8 | # Author: Alexander Afanasyev <alexander.afanasyev@ucla.edu> |
| 9 | # |
| 10 | |
| 11 | # |
| 12 | # Based on PyCCN code, copyrighted and licensed as follows |
| 13 | # |
| 14 | # Copyright (c) 2011-2013, Regents of the University of California |
| 15 | # BSD license, See the COPYING file for more information |
| 16 | # Written by: Derek Kulinski <takeda@takeda.tk> |
| 17 | # Jeff Burke <jburke@ucla.edu> |
| 18 | # |
| 19 | |
| 20 | import struct |
| 21 | |
| 22 | class Flag(int): |
| 23 | __initialized = False |
| 24 | _flags = None |
| 25 | _prefix = None |
| 26 | __flags_values__ = None |
| 27 | |
| 28 | @classmethod |
| 29 | def initialize(cls): |
| 30 | cls._flags = {} |
| 31 | cls.__flags_values__ = {} |
| 32 | cls.__initialized = True |
| 33 | |
| 34 | @classmethod |
| 35 | def new_flag(cls, name, value): |
| 36 | if not cls.__initialized: |
| 37 | cls.initialize() |
| 38 | |
| 39 | cls._flags[value] = name |
| 40 | |
| 41 | obj = cls(value) |
| 42 | cls.__flags_values__[value] = obj |
| 43 | |
| 44 | return obj |
| 45 | |
| 46 | def __new__(cls, value): |
| 47 | if cls.__flags_values__.has_key(value): |
| 48 | return cls.__flags_values__[value] |
| 49 | |
| 50 | return super(Flag, cls).__new__(cls, value) |
| 51 | |
| 52 | def generate_repr(self): |
| 53 | val = long(self) |
| 54 | flags = [name for i, name in self._flags.items() if i & val] |
| 55 | return " | ".join(flags) |
| 56 | |
| 57 | def __repr__(self): |
| 58 | if self._prefix: |
| 59 | return self._prefix + "." + self.generate_repr() |
| 60 | |
| 61 | t = type(self) |
| 62 | type_name = "%s.%s" % (t.__module__, t.__name__) |
| 63 | return "<flags %s of type %s>" % (self.generate_repr(), type_name) |
| 64 | |
| 65 | def __and__(self, other): |
| 66 | cls = type(self) |
| 67 | return cls(long(self) & long(other)) |
| 68 | |
| 69 | def __xor__(self, other): |
| 70 | cls = type(self) |
| 71 | return cls(long(self) ^ long(other)) |
| 72 | |
| 73 | def __or__(self, other): |
| 74 | cls = type(self) |
| 75 | return cls(long(self) | long(other)) |
| 76 | |
| 77 | class Enum(Flag): |
| 78 | def __new__(cls, value): |
| 79 | if cls.__flags_values__.has_key(value): |
| 80 | return cls.__flags_values__[value] |
| 81 | |
| 82 | if cls._flags.has_key(value): |
| 83 | return super(Enum, cls).__new__(cls, value) |
| 84 | |
| 85 | raise ValueError("invalid flag value: %d" % value) |
| 86 | |
| 87 | def generate_repr(self): |
| 88 | return self._flags[long(self)] |
| 89 | |
| 90 | def ccn2py_time(value): |
| 91 | bintime = b'\x00' * (8 - len(value)) + value |
| 92 | inttime = struct.unpack("!Q", bintime)[0] |
| 93 | return inttime / 4096.0 |
| 94 | |
| 95 | def py2ccn_time(value): |
| 96 | inttime = int(value * 4096 + 0.5) |
| 97 | bintime = struct.pack("!Q", inttime) |
| 98 | return bintime.lstrip(b'\x00') |