1
     StructOrUnion):
    kind = 'struct'


class UnionType(StructOrUnion):
    kind = 'union'


class EnumType(StructOrUnionOrEnum):
    kind = 'enum'
    partial = False
    partial_resolved = False

    def __init__(self, name, enumerators, enumvalues, baseinttype=None):
        self.name = name
        self.enumerators = enumerators
        self.enumvalues = enumvalues
        self.baseinttype = baseinttype
        self.build_c_name_with_marker()

    def force_the_name(self, forcename):
        StructOrUnionOrEnum.force_the_name(self, forcename)
        if self.forcename is None:
            name = self.get_official_name()
            self.forcename = '$' + name.replace(' ', '_')

    def check_not_partial(self):
        if self.partial and not self.partial_resolved:
            from . import ffiplatform
            raise ffiplatform.VerificationMissing(self._get_c_name())

    def build_backend_type(self, ffi, finishlist):
        self.check_not_partial()
        base_btype = self.build_baseinttype(ffi, finishlist)
        return global_cache(self, ffi, 'new_enum_type',
                            self.get_official_name(),
                            self.enumerators, self.enumvalues,
                            base_btype, key=self)

    def build_baseinttype(self, ffi, finishlist):
        if self.baseinttype is not None:
            return self.baseinttype.get_cached_btype(ffi, finishlist)
        #
        from . import api
        if self.enumvalues:
            smallest_value = min(self.enumvalues)
            largest_value = max(self.enumvalues)
        else:
            import warnings
            warnings.warn("%r has no values explicitly defined; next version "
                          "will refuse to guess which integer type it is "
                          "meant to be (unsigned/signed, int/long)"
                          % self._get_c_name())
            smallest_value = largest_value = 0
        if smallest_value < 0:   # needs a signed type
            sign = 1
            candidate1 = PrimitiveType("int")
            candidate2 = PrimitiveType("long")
        else:
            sign = 0
            candidate1 = PrimitiveType("unsigned int")
            candidate2 = PrimitiveType("unsigned long")
        btype1 = candidate1.get_cached_btype(ffi, finishlist)
        btype2 = candidate2.get_cached_btype(ffi, finishlist)
        size1 = ffi.sizeof(btype1)
        size2 = ffi.sizeof(btype2)
        if (smallest_value >= ((-1) << (8*size1-1)) and
            largest_value < (1 << (8*size1-sign))):
            return btype1
        if (smallest_value >= ((-1) << (8*size2-1)) and
            largest_value < (1 << (8*size2-sign))):
            return btype2
        raise api.CDefError("%s values don't all fit into either 'long' "
                            "or 'unsigned long'" % self._get_c_name())

def unknown_type(name, structname=None):
    if structname is None:
        structname = '$%s' % name
    tp = StructType(structname, None, None, None)
    tp.force_the_name(name)
    tp.origin = "unknown_type"
    return tp

def unknown_ptr_type(name, structname=None):
    if structname is None:
        structname = '$$%s' % name
    tp = StructType(structname, None, None, None)
    return NamedPointerType(tp, name)


global_lock = allocate_lock()

def global_cache(srctype, ffi, funcname, *args, **kwds):
    key = kwds.pop('key', (funcname, args))
    assert not kwds
    try:
        return ffi._backend.__typecache[key]
    except KeyError:
        pass
    except AttributeError:
        # initialize the __typecache attribute, either at the module level
        # if ffi._backend is a module, or at the class level if ffi._backend
        # is some instance.
        if isinstance(ffi._backend, types.ModuleType):
            ffi._backend.__typecache = weakref.WeakValueDictionary()
        else:
            type(ffi._backend).__typecache = weakref.WeakValueDictionary()
    try:
        res = getattr(ffi._backend, funcname)(*args)
    except NotImplementedError as e:
        raise NotImplementedError("%s: %r: