EmbeddedPkg: Extend NvVarStoreFormattedLib LIBRARY_CLASS

[mirror_edk2.git] / AppPkg / Applications / Python / Python-2.7.10 / Lib / copy_reg.py

"""Helper to provide extensibility for pickle/cPickle.\r
\r
This is only useful to add pickle support for extension types defined in\r
C, not for instances of user-defined classes.\r
"""\r
\r
from types import ClassType as _ClassType\r
\r
__all__ = ["pickle", "constructor",\r
           "add_extension", "remove_extension", "clear_extension_cache"]\r
\r
dispatch_table = {}\r
\r
def pickle(ob_type, pickle_function, constructor_ob=None):\r
    if type(ob_type) is _ClassType:\r
        raise TypeError("copy_reg is not intended for use with classes")\r
\r
    if not hasattr(pickle_function, '__call__'):\r
        raise TypeError("reduction functions must be callable")\r
    dispatch_table[ob_type] = pickle_function\r
\r
    # The constructor_ob function is a vestige of safe for unpickling.\r
    # There is no reason for the caller to pass it anymore.\r
    if constructor_ob is not None:\r
        constructor(constructor_ob)\r
\r
def constructor(object):\r
    if not hasattr(object, '__call__'):\r
        raise TypeError("constructors must be callable")\r
\r
# Example: provide pickling support for complex numbers.\r
\r
try:\r
    complex\r
except NameError:\r
    pass\r
else:\r
\r
    def pickle_complex(c):\r
        return complex, (c.real, c.imag)\r
\r
    pickle(complex, pickle_complex, complex)\r
\r
# Support for pickling new-style objects\r
\r
def _reconstructor(cls, base, state):\r
    if base is object:\r
        obj = object.__new__(cls)\r
    else:\r
        obj = base.__new__(cls, state)\r
        if base.__init__ != object.__init__:\r
            base.__init__(obj, state)\r
    return obj\r
\r
_HEAPTYPE = 1<<9\r
\r
# Python code for object.__reduce_ex__ for protocols 0 and 1\r
\r
def _reduce_ex(self, proto):\r
    assert proto < 2\r
    for base in self.__class__.__mro__:\r
        if hasattr(base, '__flags__') and not base.__flags__ & _HEAPTYPE:\r
            break\r
    else:\r
        base = object # not really reachable\r
    if base is object:\r
        state = None\r
    else:\r
        if base is self.__class__:\r
            raise TypeError, "can't pickle %s objects" % base.__name__\r
        state = base(self)\r
    args = (self.__class__, base, state)\r
    try:\r
        getstate = self.__getstate__\r
    except AttributeError:\r
        if getattr(self, "__slots__", None):\r
            raise TypeError("a class that defines __slots__ without "\r
                            "defining __getstate__ cannot be pickled")\r
        try:\r
            dict = self.__dict__\r
        except AttributeError:\r
            dict = None\r
    else:\r
        dict = getstate()\r
    if dict:\r
        return _reconstructor, args, dict\r
    else:\r
        return _reconstructor, args\r
\r
# Helper for __reduce_ex__ protocol 2\r
\r
def __newobj__(cls, *args):\r
    return cls.__new__(cls, *args)\r
\r
def _slotnames(cls):\r
    """Return a list of slot names for a given class.\r
\r
    This needs to find slots defined by the class and its bases, so we\r
    can't simply return the __slots__ attribute.  We must walk down\r
    the Method Resolution Order and concatenate the __slots__ of each\r
    class found there.  (This assumes classes don't modify their\r
    __slots__ attribute to misrepresent their slots after the class is\r
    defined.)\r
    """\r
\r
    # Get the value from a cache in the class if possible\r
    names = cls.__dict__.get("__slotnames__")\r
    if names is not None:\r
        return names\r
\r
    # Not cached -- calculate the value\r
    names = []\r
    if not hasattr(cls, "__slots__"):\r
        # This class has no slots\r
        pass\r
    else:\r
        # Slots found -- gather slot names from all base classes\r
        for c in cls.__mro__:\r
            if "__slots__" in c.__dict__:\r
                slots = c.__dict__['__slots__']\r
                # if class has a single slot, it can be given as a string\r
                if isinstance(slots, basestring):\r
                    slots = (slots,)\r
                for name in slots:\r
                    # special descriptors\r
                    if name in ("__dict__", "__weakref__"):\r
                        continue\r
                    # mangled names\r
                    elif name.startswith('__') and not name.endswith('__'):\r
                        names.append('_%s%s' % (c.__name__, name))\r
                    else:\r
                        names.append(name)\r
\r
    # Cache the outcome in the class if at all possible\r
    try:\r
        cls.__slotnames__ = names\r
    except:\r
        pass # But don't die if we can't\r
\r
    return names\r
\r
# A registry of extension codes.  This is an ad-hoc compression\r
# mechanism.  Whenever a global reference to <module>, <name> is about\r
# to be pickled, the (<module>, <name>) tuple is looked up here to see\r
# if it is a registered extension code for it.  Extension codes are\r
# universal, so that the meaning of a pickle does not depend on\r
# context.  (There are also some codes reserved for local use that\r
# don't have this restriction.)  Codes are positive ints; 0 is\r
# reserved.\r
\r
_extension_registry = {}                # key -> code\r
_inverted_registry = {}                 # code -> key\r
_extension_cache = {}                   # code -> object\r
# Don't ever rebind those names:  cPickle grabs a reference to them when\r
# it's initialized, and won't see a rebinding.\r
\r
def add_extension(module, name, code):\r
    """Register an extension code."""\r
    code = int(code)\r
    if not 1 <= code <= 0x7fffffff:\r
        raise ValueError, "code out of range"\r
    key = (module, name)\r
    if (_extension_registry.get(key) == code and\r
        _inverted_registry.get(code) == key):\r
        return # Redundant registrations are benign\r
    if key in _extension_registry:\r
        raise ValueError("key %s is already registered with code %s" %\r
                         (key, _extension_registry[key]))\r
    if code in _inverted_registry:\r
        raise ValueError("code %s is already in use for key %s" %\r
                         (code, _inverted_registry[code]))\r
    _extension_registry[key] = code\r
    _inverted_registry[code] = key\r
\r
def remove_extension(module, name, code):\r
    """Unregister an extension code.  For testing only."""\r
    key = (module, name)\r
    if (_extension_registry.get(key) != code or\r
        _inverted_registry.get(code) != key):\r
        raise ValueError("key %s is not registered with code %s" %\r
                         (key, code))\r
    del _extension_registry[key]\r
    del _inverted_registry[code]\r
    if code in _extension_cache:\r
        del _extension_cache[code]\r
\r
def clear_extension_cache():\r
    _extension_cache.clear()\r
\r
# Standard extension code assignments\r
\r
# Reserved ranges\r
\r
# First  Last Count  Purpose\r
#     1   127   127  Reserved for Python standard library\r
#   128   191    64  Reserved for Zope\r
#   192   239    48  Reserved for 3rd parties\r
#   240   255    16  Reserved for private use (will never be assigned)\r
#   256   Inf   Inf  Reserved for future assignment\r
\r
# Extension codes are assigned by the Python Software Foundation.\r