diff options
Diffstat (limited to 'Lib/pickle.py')
-rw-r--r-- | Lib/pickle.py | 105 |
1 files changed, 48 insertions, 57 deletions
diff --git a/Lib/pickle.py b/Lib/pickle.py index 7512787..a60b1b7 100644 --- a/Lib/pickle.py +++ b/Lib/pickle.py @@ -27,6 +27,7 @@ from types import FunctionType from copyreg import dispatch_table from copyreg import _extension_registry, _inverted_registry, _extension_cache from itertools import islice +from functools import partial import sys from sys import maxsize from struct import pack, unpack @@ -544,7 +545,7 @@ class _Pickler: write = self.write func_name = getattr(func, "__name__", "") - if self.proto >= 4 and func_name == "__newobj_ex__": + if self.proto >= 2 and func_name == "__newobj_ex__": cls, args, kwargs = args if not hasattr(cls, "__new__"): raise PicklingError("args[0] from {} args has no __new__" @@ -552,10 +553,16 @@ class _Pickler: if obj is not None and cls is not obj.__class__: raise PicklingError("args[0] from {} args has the wrong class" .format(func_name)) - save(cls) - save(args) - save(kwargs) - write(NEWOBJ_EX) + if self.proto >= 4: + save(cls) + save(args) + save(kwargs) + write(NEWOBJ_EX) + else: + func = partial(cls.__new__, cls, *args, **kwargs) + save(func) + save(()) + write(REDUCE) elif self.proto >= 2 and func_name == "__newobj__": # A __reduce__ implementation can direct protocol 2 or newer to # use the more efficient NEWOBJ opcode, while still @@ -1024,7 +1031,7 @@ class _Unpickler: self._unframer = _Unframer(self._file_read, self._file_readline) self.read = self._unframer.read self.readline = self._unframer.readline - self.mark = object() # any new unique object + self.metastack = [] self.stack = [] self.append = self.stack.append self.proto = 0 @@ -1040,20 +1047,12 @@ class _Unpickler: except _Stop as stopinst: return stopinst.value - # Return largest index k such that self.stack[k] is self.mark. - # If the stack doesn't contain a mark, eventually raises IndexError. - # This could be sped by maintaining another stack, of indices at which - # the mark appears. For that matter, the latter stack would suffice, - # and we wouldn't need to push mark objects on self.stack at all. - # Doing so is probably a good thing, though, since if the pickle is - # corrupt (or hostile) we may get a clue from finding self.mark embedded - # in unpickled objects. - def marker(self): - stack = self.stack - mark = self.mark - k = len(stack)-1 - while stack[k] is not mark: k = k-1 - return k + # Return a list of items pushed in the stack after last MARK instruction. + def pop_mark(self): + items = self.stack + self.stack = self.metastack.pop() + self.append = self.stack.append + return items def persistent_load(self, pid): raise UnpicklingError("unsupported persistent id encountered") @@ -1230,8 +1229,8 @@ class _Unpickler: dispatch[SHORT_BINUNICODE[0]] = load_short_binunicode def load_tuple(self): - k = self.marker() - self.stack[k:] = [tuple(self.stack[k+1:])] + items = self.pop_mark() + self.append(tuple(items)) dispatch[TUPLE[0]] = load_tuple def load_empty_tuple(self): @@ -1263,21 +1262,20 @@ class _Unpickler: dispatch[EMPTY_SET[0]] = load_empty_set def load_frozenset(self): - k = self.marker() - self.stack[k:] = [frozenset(self.stack[k+1:])] + items = self.pop_mark() + self.append(frozenset(items)) dispatch[FROZENSET[0]] = load_frozenset def load_list(self): - k = self.marker() - self.stack[k:] = [self.stack[k+1:]] + items = self.pop_mark() + self.append(items) dispatch[LIST[0]] = load_list def load_dict(self): - k = self.marker() - items = self.stack[k+1:] + items = self.pop_mark() d = {items[i]: items[i+1] for i in range(0, len(items), 2)} - self.stack[k:] = [d] + self.append(d) dispatch[DICT[0]] = load_dict # INST and OBJ differ only in how they get a class object. It's not @@ -1285,9 +1283,7 @@ class _Unpickler: # previously diverged and grew different bugs. # klass is the class to instantiate, and k points to the topmost mark # object, following which are the arguments for klass.__init__. - def _instantiate(self, klass, k): - args = tuple(self.stack[k+1:]) - del self.stack[k:] + def _instantiate(self, klass, args): if (args or not isinstance(klass, type) or hasattr(klass, "__getinitargs__")): try: @@ -1303,14 +1299,14 @@ class _Unpickler: module = self.readline()[:-1].decode("ascii") name = self.readline()[:-1].decode("ascii") klass = self.find_class(module, name) - self._instantiate(klass, self.marker()) + self._instantiate(klass, self.pop_mark()) dispatch[INST[0]] = load_inst def load_obj(self): # Stack is ... markobject classobject arg1 arg2 ... - k = self.marker() - klass = self.stack.pop(k+1) - self._instantiate(klass, k) + args = self.pop_mark() + cls = args.pop(0) + self._instantiate(cls, args) dispatch[OBJ[0]] = load_obj def load_newobj(self): @@ -1395,12 +1391,14 @@ class _Unpickler: dispatch[REDUCE[0]] = load_reduce def load_pop(self): - del self.stack[-1] + if self.stack: + del self.stack[-1] + else: + self.pop_mark() dispatch[POP[0]] = load_pop def load_pop_mark(self): - k = self.marker() - del self.stack[k:] + self.pop_mark() dispatch[POP_MARK[0]] = load_pop_mark def load_dup(self): @@ -1456,17 +1454,14 @@ class _Unpickler: dispatch[APPEND[0]] = load_append def load_appends(self): - stack = self.stack - mark = self.marker() - list_obj = stack[mark - 1] - items = stack[mark + 1:] + items = self.pop_mark() + list_obj = self.stack[-1] if isinstance(list_obj, list): list_obj.extend(items) else: append = list_obj.append for item in items: append(item) - del stack[mark:] dispatch[APPENDS[0]] = load_appends def load_setitem(self): @@ -1478,27 +1473,21 @@ class _Unpickler: dispatch[SETITEM[0]] = load_setitem def load_setitems(self): - stack = self.stack - mark = self.marker() - dict = stack[mark - 1] - for i in range(mark + 1, len(stack), 2): - dict[stack[i]] = stack[i + 1] - - del stack[mark:] + items = self.pop_mark() + dict = self.stack[-1] + for i in range(0, len(items), 2): + dict[items[i]] = items[i + 1] dispatch[SETITEMS[0]] = load_setitems def load_additems(self): - stack = self.stack - mark = self.marker() - set_obj = stack[mark - 1] - items = stack[mark + 1:] + items = self.pop_mark() + set_obj = self.stack[-1] if isinstance(set_obj, set): set_obj.update(items) else: add = set_obj.add for item in items: add(item) - del stack[mark:] dispatch[ADDITEMS[0]] = load_additems def load_build(self): @@ -1526,7 +1515,9 @@ class _Unpickler: dispatch[BUILD[0]] = load_build def load_mark(self): - self.append(self.mark) + self.metastack.append(self.stack) + self.stack = [] + self.append = self.stack.append dispatch[MARK[0]] = load_mark def load_stop(self): |