1 files changed, 0 insertions, 177 deletions
diff --git a/Lib/Bastion.py b/Lib/Bastion.py
deleted file mode 100644
index 5331ba9..0000000
--- a/Lib/Bastion.py
+++ /dev/null
@@ -1,177 +0,0 @@
-"""Bastionification utility.
-
-A bastion (for another object -- the 'original') is an object that has
-the same methods as the original but does not give access to its
-instance variables.  Bastions have a number of uses, but the most
-obvious one is to provide code executing in restricted mode with a
-safe interface to an object implemented in unrestricted mode.
-
-The bastionification routine has an optional second argument which is
-a filter function.  Only those methods for which the filter method
-(called with the method name as argument) returns true are accessible.
-The default filter method returns true unless the method name begins
-with an underscore.
-
-There are a number of possible implementations of bastions.  We use a
-'lazy' approach where the bastion's __getattr__() discipline does all
-the work for a particular method the first time it is used.  This is
-usually fastest, especially if the user doesn't call all available
-methods.  The retrieved methods are stored as instance variables of
-the bastion, so the overhead is only occurred on the first use of each
-method.
-
-Detail: the bastion class has a __repr__() discipline which includes
-the repr() of the original object.  This is precomputed when the
-bastion is created.
-
-"""
-
-__all__ = ["BastionClass", "Bastion"]
-
-from types import MethodType
-
-
-class BastionClass:
-
-    """Helper class used by the Bastion() function.
-
-    You could subclass this and pass the subclass as the bastionclass
-    argument to the Bastion() function, as long as the constructor has
-    the same signature (a get() function and a name for the object).
-
-    """
-
-    def __init__(self, get, name):
-        """Constructor.
-
-        Arguments:
-
-        get - a function that gets the attribute value (by name)
-        name - a human-readable name for the original object
-               (suggestion: use repr(object))
-
-        """
-        self._get_ = get
-        self._name_ = name
-
-    def __repr__(self):
-        """Return a representation string.
-
-        This includes the name passed in to the constructor, so that
-        if you print the bastion during debugging, at least you have
-        some idea of what it is.
-
-        """
-        return "<Bastion for %s>" % self._name_
-
-    def __getattr__(self, name):
-        """Get an as-yet undefined attribute value.
-
-        This calls the get() function that was passed to the
-        constructor.  The result is stored as an instance variable so
-        that the next time the same attribute is requested,
-        __getattr__() won't be invoked.
-
-        If the get() function raises an exception, this is simply
-        passed on -- exceptions are not cached.
-
-        """
-        attribute = self._get_(name)
-        self.__dict__[name] = attribute
-        return attribute
-
-
-def Bastion(object, filter = lambda name: name[:1] != '_',
-            name=None, bastionclass=BastionClass):
-    """Create a bastion for an object, using an optional filter.
-
-    See the Bastion module's documentation for background.
-
-    Arguments:
-
-    object - the original object
-    filter - a predicate that decides whether a function name is OK;
-             by default all names are OK that don't start with '_'
-    name - the name of the object; default repr(object)
-    bastionclass - class used to create the bastion; default BastionClass
-
-    """
-
-    raise RuntimeError, "This code is not secure in Python 2.2 and later"
-
-    # Note: we define *two* ad-hoc functions here, get1 and get2.
-    # Both are intended to be called in the same way: get(name).
-    # It is clear that the real work (getting the attribute
-    # from the object and calling the filter) is done in get1.
-    # Why can't we pass get1 to the bastion?  Because the user
-    # would be able to override the filter argument!  With get2,
-    # overriding the default argument is no security loophole:
-    # all it does is call it.
-    # Also notice that we can't place the object and filter as
-    # instance variables on the bastion object itself, since
-    # the user has full access to all instance variables!
-
-    def get1(name, object=object, filter=filter):
-        """Internal function for Bastion().  See source comments."""
-        if filter(name):
-            attribute = getattr(object, name)
-            if type(attribute) == MethodType:
-                return attribute
-        raise AttributeError, name
-
-    def get2(name, get1=get1):
-        """Internal function for Bastion().  See source comments."""
-        return get1(name)
-
-    if name is None:
-        name = repr(object)
-    return bastionclass(get2, name)
-
-
-def _test():
-    """Test the Bastion() function."""
-    class Original:
-        def __init__(self):
-            self.sum = 0
-        def add(self, n):
-            self._add(n)
-        def _add(self, n):
-            self.sum = self.sum + n
-        def total(self):
-            return self.sum
-    o = Original()
-    b = Bastion(o)
-    testcode = """if 1:
-    b.add(81)
-    b.add(18)
-    print "b.total() =", b.total()
-    try:
-        print "b.sum =", b.sum,
-    except:
-        print "inaccessible"
-    else:
-        print "accessible"
-    try:
-        print "b._add =", b._add,
-    except:
-        print "inaccessible"
-    else:
-        print "accessible"
-    try:
-        print "b._get_.__defaults__ =", map(type, b._get_.__defaults__),
-    except:
-        print "inaccessible"
-    else:
-        print "accessible"
-    \n"""
-    exec(testcode)
-    print('='*20, "Using rexec:", '='*20)
-    import rexec
-    r = rexec.RExec()
-    m = r.add_module('__main__')
-    m.b = b
-    r.r_exec(testcode)
-
-
-if __name__ == '__main__':
-    _test()