Optimizations and one intentional loophole by Jim Fulton.
The optimizations consist mostly of using local variables to cache
methods or instance variables used a lot (e.g. "self.write").
The loopholes allows marshalling extension types as long as they have
a __class__ attribute (in which case they may support the rest of the
class piclking protocol as well). This allows pickling MESS extension
types.
diff --git a/Lib/pickle.py b/Lib/pickle.py
index 8f5da40..dde3dee 100644
--- a/Lib/pickle.py
+++ b/Lib/pickle.py
@@ -126,7 +126,7 @@
I have no answers. Garbage Collection may also become a problem here.)
"""
-__version__ = "1.5" # Code version
+__version__ = "1.6" # Code version
from types import *
import string
@@ -200,8 +200,11 @@
try:
f = self.dispatch[t]
except KeyError:
- raise PicklingError, \
- "can't pickle %s objects" % `t.__name__`
+ if hasattr(object, '__class__'):
+ f = self.dispatch[InstanceType]
+ else:
+ raise PicklingError, \
+ "can't pickle %s objects" % `t.__name__`
f(self, object)
def persistent_id(self, object):
@@ -234,66 +237,75 @@
def save_tuple(self, object):
d = id(object)
- self.write(MARK)
+ write = self.write
+ save = self.save
+ has_key = self.memo.has_key
+ write(MARK)
n = len(object)
for k in range(n):
- self.save(object[k])
- if self.memo.has_key(d):
+ save(object[k])
+ if has_key(d):
# Saving object[k] has saved us!
while k >= 0:
- self.write(POP)
+ write(POP)
k = k-1
- self.write(GET + `d` + '\n')
+ write(GET + `d` + '\n')
break
else:
- self.write(TUPLE + PUT + `d` + '\n')
+ write(TUPLE + PUT + `d` + '\n')
self.memo[d] = object
dispatch[TupleType] = save_tuple
def save_list(self, object):
d = id(object)
- self.write(MARK)
+ write = self.write
+ save = self.save
+ write(MARK)
n = len(object)
for k in range(n):
item = object[k]
if not safe(item):
break
- self.save(item)
+ save(item)
else:
k = n
- self.write(LIST + PUT + `d` + '\n')
+ write(LIST + PUT + `d` + '\n')
self.memo[d] = object
for k in range(k, n):
item = object[k]
- self.save(item)
- self.write(APPEND)
+ save(item)
+ write(APPEND)
dispatch[ListType] = save_list
def save_dict(self, object):
d = id(object)
- self.write(MARK)
+ write = self.write
+ save = self.save
+ write(MARK)
items = object.items()
n = len(items)
for k in range(n):
key, value = items[k]
if not safe(key) or not safe(value):
break
- self.save(key)
- self.save(value)
+ save(key)
+ save(value)
else:
k = n
self.write(DICT + PUT + `d` + '\n')
self.memo[d] = object
for k in range(k, n):
key, value = items[k]
- self.save(key)
- self.save(value)
- self.write(SETITEM)
+ save(key)
+ save(value)
+ write(SETITEM)
dispatch[DictionaryType] = save_dict
def save_inst(self, object):
d = id(object)
cls = object.__class__
+ write = self.write
+ save = self.save
module = whichmodule(cls)
name = cls.__name__
if hasattr(object, '__getinitargs__'):
@@ -301,11 +313,11 @@
len(args) # XXX Assert it's a sequence
else:
args = ()
- self.write(MARK)
+ write(MARK)
for arg in args:
- self.save(arg)
- self.write(INST + module + '\n' + name + '\n' +
- PUT + `d` + '\n')
+ save(arg)
+ write(INST + module + '\n' + name + '\n' +
+ PUT + `d` + '\n')
self.memo[d] = object
try:
getstate = object.__getstate__
@@ -313,8 +325,8 @@
stuff = object.__dict__
else:
stuff = getstate()
- self.save(stuff)
- self.write(BUILD)
+ save(stuff)
+ write(BUILD)
dispatch[InstanceType] = save_inst
def save_class(self, object):
@@ -361,16 +373,21 @@
def load(self):
self.mark = ['spam'] # Any new unique object
self.stack = []
+ self.append = self.stack.append
+ read = self.read
+ dispatch = self.dispatch
try:
while 1:
- key = self.read(1)
- self.dispatch[key](self)
+ key = read(1)
+ dispatch[key](self)
except STOP, value:
return value
def marker(self):
- k = len(self.stack)-1
- while self.stack[k] != self.mark: k = k-1
+ stack = self.stack
+ mark = self.mark
+ k = len(stack)-1
+ while stack[k] is not mark: k = k-1
return k
dispatch = {}
@@ -381,27 +398,28 @@
def load_persid(self):
pid = self.readline()[:-1]
- self.stack.append(self.persistent_load(pid))
+ self.append(self.persistent_load(pid))
dispatch[PERSID] = load_persid
def load_none(self):
- self.stack.append(None)
+ self.append(None)
dispatch[NONE] = load_none
def load_int(self):
- self.stack.append(string.atoi(self.readline()[:-1], 0))
+ self.append(string.atoi(self.readline()[:-1], 0))
dispatch[INT] = load_int
def load_long(self):
- self.stack.append(string.atol(self.readline()[:-1], 0))
+ self.append(string.atol(self.readline()[:-1], 0))
dispatch[LONG] = load_long
def load_float(self):
- self.stack.append(string.atof(self.readline()[:-1]))
+ self.append(string.atof(self.readline()[:-1]))
dispatch[FLOAT] = load_float
def load_string(self):
- self.stack.append(eval(self.readline()[:-1]))
+ self.append(eval(self.readline()[:-1],
+ {'__builtins__': {}})) # Let's be careful
dispatch[STRING] = load_string
def load_tuple(self):
@@ -433,14 +451,14 @@
name = self.readline()[:-1]
klass = self.find_class(module, name)
value = apply(klass, args)
- self.stack.append(value)
+ self.append(value)
dispatch[INST] = load_inst
def load_class(self):
module = self.readline()[:-1]
name = self.readline()[:-1]
klass = self.find_class(module, name)
- self.stack.append(klass)
+ self.append(klass)
return klass
dispatch[CLASS] = load_class
@@ -453,7 +471,9 @@
"Failed to import class %s from module %s" % \
(name, module)
klass = env[name]
- if type(klass) != ClassType:
+ # if type(klass) != ClassType:
+ if (type(klass) is FunctionType or
+ type(klass) is BuiltinFunctionType):
raise SystemError, \
"Imported object %s from module %s is not a class" % \
(name, module)
@@ -464,11 +484,11 @@
dispatch[POP] = load_pop
def load_dup(self):
- stack.append(stack[-1])
+ self.append(stack[-1])
dispatch[DUP] = load_dup
def load_get(self):
- self.stack.append(self.memo[self.readline()[:-1]])
+ self.append(self.memo[self.readline()[:-1]])
dispatch[GET] = load_get
def load_put(self):
@@ -476,35 +496,39 @@
dispatch[PUT] = load_put
def load_append(self):
- value = self.stack[-1]
- del self.stack[-1]
- list = self.stack[-1]
+ stack = self.stack
+ value = stack[-1]
+ del stack[-1]
+ list = stack[-1]
list.append(value)
dispatch[APPEND] = load_append
def load_setitem(self):
- value = self.stack[-1]
- key = self.stack[-2]
- del self.stack[-2:]
- dict = self.stack[-1]
+ stack = self.stack
+ value = stack[-1]
+ key = stack[-2]
+ del stack[-2:]
+ dict = stack[-1]
dict[key] = value
dispatch[SETITEM] = load_setitem
def load_build(self):
- value = self.stack[-1]
- del self.stack[-1]
- inst = self.stack[-1]
+ stack = self.stack
+ value = stack[-1]
+ del stack[-1]
+ inst = stack[-1]
try:
setstate = inst.__setstate__
except AttributeError:
+ instdict = inst.__dict__
for key in value.keys():
- inst.__dict__[key] = value[key]
+ instdict[key] = value[key]
else:
setstate(value)
dispatch[BUILD] = load_build
def load_mark(self):
- self.stack.append(self.mark)
+ self.append(self.mark)
dispatch[MARK] = load_mark
def load_stop(self):
@@ -516,12 +540,13 @@
# Shorthands
+from StringIO import StringIO
+
def dump(object, file):
Pickler(file).dump(object)
def dumps(object):
- import StringIO
- file = StringIO.StringIO()
+ file = StringIO()
Pickler(file).dump(object)
return file.getvalue()
@@ -529,8 +554,7 @@
return Unpickler(file).load()
def loads(str):
- import StringIO
- file = StringIO.StringIO(str)
+ file = StringIO(str)
return Unpickler(file).load()
@@ -545,7 +569,7 @@
c = C()
c.foo = 1
c.bar = 2L
- x = [0,1,2,3]
+ x = [0, 1, 2, 3]
y = ('abc', 'abc', c, c)
x.append(y)
x.append(y)