# This file is dual licensed under the terms of the Apache License, Version # 2.0, and the BSD License. See the LICENSE file in the root of this repository # for complete details. from __future__ import absolute_import, division, print_function import abc import binascii import inspect import sys import warnings # the functions deprecated in 1.0 and 1.4 are on an arbitrarily extended # deprecation cycle and should not be removed until we agree on when that cycle # ends. DeprecatedIn10 = DeprecationWarning DeprecatedIn14 = DeprecationWarning DeprecatedIn16 = DeprecationWarning def read_only_property(name): return property(lambda self: getattr(self, name)) def register_interface(iface): def register_decorator(klass): verify_interface(iface, klass) iface.register(klass) return klass return register_decorator def register_interface_if(predicate, iface): def register_decorator(klass): if predicate: verify_interface(iface, klass) iface.register(klass) return klass return register_decorator if hasattr(int, "from_bytes"): int_from_bytes = int.from_bytes else: def int_from_bytes(data, byteorder, signed=False): assert byteorder == 'big' assert not signed # call bytes() on data to allow the use of bytearrays return int(bytes(data).encode('hex'), 16) def int_to_bytes(integer, length=None): hex_string = '%x' % integer if length is None: n = len(hex_string) else: n = length * 2 return binascii.unhexlify(hex_string.zfill(n + (n & 1))) class InterfaceNotImplemented(Exception): pass if hasattr(inspect, "signature"): signature = inspect.signature else: signature = inspect.getargspec def verify_interface(iface, klass): for method in iface.__abstractmethods__: if not hasattr(klass, method): raise InterfaceNotImplemented( "{0} is missing a {1!r} method".format(klass, method) ) if isinstance(getattr(iface, method), abc.abstractproperty): # Can't properly verify these yet. continue sig = signature(getattr(iface, method)) actual = signature(getattr(klass, method)) if sig != actual: raise InterfaceNotImplemented( "{0}.{1}'s signature differs from the expected. Expected: " "{2!r}. Received: {3!r}".format( klass, method, sig, actual ) ) if sys.version_info >= (2, 7): def bit_length(x): return x.bit_length() else: def bit_length(x): return len(bin(x)) - (2 + (x <= 0)) class _DeprecatedValue(object): def __init__(self, value, message, warning_class): self.value = value self.message = message self.warning_class = warning_class class _ModuleWithDeprecations(object): def __init__(self, module): self.__dict__["_module"] = module def __getattr__(self, attr): obj = getattr(self._module, attr) if isinstance(obj, _DeprecatedValue): warnings.warn(obj.message, obj.warning_class, stacklevel=2) obj = obj.value return obj def __setattr__(self, attr, value): setattr(self._module, attr, value) def __delattr__(self, attr): obj = getattr(self._module, attr) if isinstance(obj, _DeprecatedValue): warnings.warn(obj.message, obj.warning_class, stacklevel=2) delattr(self._module, attr) def __dir__(self): return ["_module"] + dir(self._module) def deprecated(value, module_name, message, warning_class): module = sys.modules[module_name] if not isinstance(module, _ModuleWithDeprecations): sys.modules[module_name] = module = _ModuleWithDeprecations(module) return _DeprecatedValue(value, message, warning_class)