"""Create portable serialized representations of Python objects. See module cPickle for a (much) faster implementation. See module copy_reg for a mechanism for registering custom picklers. See module pickletools source for extensive comments. Classes: Pickler Unpickler Functions: dump(object, file) dumps(object) -> string load(file) -> object loads(string) -> object Misc variables: __version__ format_version compatible_formats """ __version__ = "$Revision$" # Code version from types import * from copy_reg import dispatch_table, _reconstructor from copy_reg import extension_registry, inverted_registry, extension_cache import marshal import sys import struct import re import warnings __all__ = ["PickleError", "PicklingError", "UnpicklingError", "Pickler", "Unpickler", "dump", "dumps", "load", "loads"] # These are purely informational; no code uses these. format_version = "2.0" # File format version we write compatible_formats = ["1.0", # Original protocol 0 "1.1", # Protocol 0 with INST added "1.2", # Original protocol 1 "1.3", # Protocol 1 with BINFLOAT added "2.0", # Protocol 2 ] # Old format versions we can read # Why use struct.pack() for pickling but marshal.loads() for # unpickling? struct.pack() is 40% faster than marshal.dumps(), but # marshal.loads() is twice as fast as struct.unpack()! mloads = marshal.loads class PickleError(Exception): """A common base class for the other pickling exceptions.""" pass class PicklingError(PickleError): """This exception is raised when an unpicklable object is passed to the dump() method. """ pass class UnpicklingError(PickleError): """This exception is raised when there is a problem unpickling an object, such as a security violation. Note that other exceptions may also be raised during unpickling, including (but not necessarily limited to) AttributeError, EOFError, ImportError, and IndexError. """ pass # An instance of _Stop is raised by Unpickler.load_stop() in response to # the STOP opcode, passing the object that is the result of unpickling. class _Stop(Exception): def __init__(self, value): self.value = value # Jython has PyStringMap; it's a dict subclass with string keys try: from org.python.core import PyStringMap except ImportError: PyStringMap = None # UnicodeType may or may not be exported (normally imported from types) try: UnicodeType except NameError: UnicodeType = None # Pickle opcodes. See pickletools.py for extensive docs. The listing # here is in kind-of alphabetical order of 1-character pickle code. # pickletools groups them by purpose. MARK = '(' # push special markobject on stack STOP = '.' # every pickle ends with STOP POP = '0' # discard topmost stack item POP_MARK = '1' # discard stack top through topmost markobject DUP = '2' # duplicate top stack item FLOAT = 'F' # push float object; decimal string argument INT = 'I' # push integer or bool; decimal string argument BININT = 'J' # push four-byte signed int BININT1 = 'K' # push 1-byte unsigned int LONG = 'L' # push long; decimal string argument BININT2 = 'M' # push 2-byte unsigned int NONE = 'N' # push None PERSID = 'P' # push persistent object; id is taken from string arg BINPERSID = 'Q' # " " " ; " " " " stack REDUCE = 'R' # apply callable to argtuple, both on stack STRING = 'S' # push string; NL-terminated string argument BINSTRING = 'T' # push string; counted binary string argument SHORT_BINSTRING = 'U' # " " ; " " " " < 256 bytes UNICODE = 'V' # push Unicode string; raw-unicode-escaped'd argument BINUNICODE = 'X' # " " " ; counted UTF-8 string argument APPEND = 'a' # append stack top to list below it BUILD = 'b' # call __setstate__ or __dict__.update() GLOBAL = 'c' # push self.find_class(modname, name); 2 string args DICT = 'd' # build a dict from stack items EMPTY_DICT = '}' # push empty dict APPENDS = 'e' # extend list on stack by topmost stack slice GET = 'g' # push item from memo on stack; index is string arg BINGET = 'h' # " " " " " " ; " " 1-byte arg INST = 'i' # build & push class instance LONG_BINGET = 'j' # push item from memo on stack; index is 4-byte arg LIST = 'l' # build list from topmost stack items EMPTY_LIST = ']' # push empty list OBJ = 'o' # build & push class instance PUT = 'p' # store stack top in memo; index is string arg BINPUT = 'q' # " " " " " ; " " 1-byte arg LONG_BINPUT = 'r' # " " " " " ; " " 4-byte arg SETITEM = 's' # add key+value pair to dict TUPLE = 't' # build tuple from topmost stack items EMPTY_TUPLE = ')' # push empty tuple SETITEMS = 'u' # modify dict by adding topmost key+value pairs BINFLOAT = 'G' # push float; arg is 8-byte float encoding TRUE = 'I01\n' # not an opcode; see INT docs in pickletools.py FALSE = 'I00\n' # not an opcode; see INT docs in pickletools.py # Protocol 2 PROTO = '\x80' # identify pickle protocol NEWOBJ = '\x81' # build object by applying cls.__new__ to argtuple EXT1 = '\x82' # push object from extension registry; 1-byte index EXT2 = '\x83' # ditto, but 2-byte index EXT4 = '\x84' # ditto, but 4-byte index TUPLE1 = '\x85' # build 1-tuple from stack top TUPLE2 = '\x86' # build 2-tuple from two topmost stack items TUPLE3 = '\x87' # build 3-tuple from three topmost stack items NEWTRUE = '\x88' # push True NEWFALSE = '\x89' # push False LONG1 = '\x8a' # push long from < 256 bytes LONG4 = '\x8b' # push really big long _tuplesize2code = [EMPTY_TUPLE, TUPLE1, TUPLE2, TUPLE3] __all__.extend([x for x in dir() if re.match("[A-Z][A-Z0-9_]+$",x)]) del x # Pickling machinery class Pickler: def __init__(self, file, proto=1): """This takes a file-like object for writing a pickle data stream. The optional proto argument tells the pickler to use the given protocol; supported protocols are 0, 1, 2. The default protocol is 1 (in previous Python versions the default was 0). Protocol 1 is more efficient than protocol 0; protocol 2 is more efficient than protocol 1. Protocol 2 is not the default because it is not supported by older Python versions. XXX Protocol 2 is not yet implemented. The file parameter must have a write() method that accepts a single string argument. It can thus be an open file object, a StringIO object, or any other custom object that meets this interface. """ if proto not in (0, 1, 2): raise ValueError, "pickle protocol must be 0, 1 or 2" self.write = file.write self.memo = {} self.proto = int(proto) self.bin = proto >= 1 self.fast = 0 def clear_memo(self): """Clears the pickler's "memo". The memo is the data structure that remembers which objects the pickler has already seen, so that shared or recursive objects are pickled by reference and not by value. This method is useful when re-using picklers. """ self.memo.clear() def dump(self, obj): """Write a pickled representation of obj to the open file. Either the binary or ASCII format will be used, depending on the value of the bin flag passed to the constructor. """ if self.proto >= 2: self.write(PROTO + chr(self.proto)) self.save(obj) self.write(STOP) def memoize(self, obj): """Store an object in the memo.""" # The Pickler memo is a dictionary mapping object ids to 2-tuples # that contain the Unpickler memo key and the object being memoized. # The memo key is written to the pickle and will become # the key in the Unpickler's memo. The object is stored in the # Pickler memo so that transient objects are kept alive during # pickling. # The use of the Unpickler memo length as the memo key is just a # convention. The only requirement is that the memo values be unique. # But there appears no advantage to any other scheme, and this # scheme allows the Unpickler memo to be implemented as a plain (but # growable) array, indexed by memo key. if self.fast: return assert id(obj) not in self.memo memo_len = len(self.memo) self.write(self.put(memo_len)) self.memo[id(obj)] = memo_len, obj # Return a PUT (BINPUT, LONG_BINPUT) opcode string, with argument i. def put(self, i, pack=struct.pack): if self.bin: if i < 256: return BINPUT + chr(i) else: return LONG_BINPUT + pack("= 2: # Protocol 2 can do better than the default __reduce__ if reduce is object.__reduce__: reduce = None if not reduce: self.save_newobj(obj) return if not reduce: raise PicklingError("Can't pickle %r object: %r" % (t.__name__, obj)) rv = reduce(obj) # Check for string returned by reduce(), meaning "save as global" if type(rv) is StringType: self.save_global(obj, rv) return # Assert that reduce() returned a tuple if type(rv) is not TupleType: raise PicklingError("%s must return string or tuple" % reduce) # Assert that it returned a 2-tuple or 3-tuple, and unpack it l = len(rv) if l == 2: func, args = rv state = None elif l == 3: func, args, state = rv else: raise PicklingError("Tuple returned by %s must have " "exactly two or three elements" % reduce) # Save the reduce() output and finally memoize the object self.save_reduce(func, args, state) self.memoize(obj) def persistent_id(self, obj): # This exists so a subclass can override it return None def save_pers(self, pid): # Save a persistent id reference if self.bin: self.save(pid) self.write(BINPERSID) else: self.write(PERSID + str(pid) + '\n') def save_reduce(self, func, args, state=None): # This API is be called by some subclasses # Assert that args is a tuple or None if not isinstance(args, TupleType): if args is None: # A hack for Jim Fulton's ExtensionClass, now deprecated. # See load_reduce() warnings.warn("__basicnew__ special case is deprecated", DeprecationWarning) else: raise PicklingError( "args from reduce() should be a tuple") # Assert that func is callable if not callable(func): raise PicklingError("func from reduce should be callable") save = self.save write = self.write save(func) save(args) write(REDUCE) if state is not None: save(state) write(BUILD) def save_newobj(self, obj): # Save a new-style class instance, using protocol 2. # XXX This is still experimental. assert self.proto >= 2 # This only works for protocol 2 t = type(obj) getnewargs = getattr(obj, "__getnewargs__", None) if getnewargs: args = getnewargs() # This bette not reference obj else: args = () save = self.save write = self.write self.save(t) save(args) write(NEWOBJ) self.memoize(obj) if isinstance(obj, list): n = len(obj) if n > 1: write(MARK) for x in obj: save(x) write(APPENDS) elif n == 1: save(obj[0]) write(APPEND) elif isinstance(obj, dict): n = len(obj) if n > 1: write(MARK) for k, v in obj.iteritems(): save(k) save(v) write(SETITEMS) elif n == 1: k, v = obj.items()[0] save(k) save(v) write(SETITEM) getstate = getattr(obj, "__getstate__", None) if getstate: # A class may define both __getstate__ and __getnewargs__. # If they are the same function, we ignore __getstate__. # This is for the benefit of protocols 0 and 1, which don't # use __getnewargs__. Note that the only way to make them # the same function is something like this: # # class C(object): # def __getstate__(self): # return ... # __getnewargs__ = __getstate__ # # No tricks are needed to ignore __setstate__; it simply # won't be called when we don't generate BUILD. # Also note that when __getnewargs__ and __getstate__ are # the same function, we don't do the default thing of # looking for __dict__ and slots either -- it is assumed # that __getnewargs__ returns all the state there is # (which should be a safe assumption since __getstate__ # returns the *same* state). if getstate == getnewargs: return try: state = getstate() except TypeError, err: # XXX Catch generic exception caused by __slots__ if str(err) != ("a class that defines __slots__ " "without defining __getstate__ " "cannot be pickled"): print repr(str(err)) raise # Not that specific exception getstate = None if not getstate: state = getattr(obj, "__dict__", None) if not state: state = None # If there are slots, the state becomes a tuple of two # items: the first item the regular __dict__ or None, and # the second a dict mapping slot names to slot values names = _slotnames(t) if names: slots = {} nil = [] for name in names: value = getattr(obj, name, nil) if value is not nil: slots[name] = value if slots: state = (state, slots) if state is not None: save(state) write(BUILD) # Methods below this point are dispatched through the dispatch table dispatch = {} def save_none(self, obj): self.write(NONE) dispatch[NoneType] = save_none def save_bool(self, obj): if self.proto >= 2: self.write(obj and NEWTRUE or NEWFALSE) else: self.write(obj and TRUE or FALSE) dispatch[bool] = save_bool def save_int(self, obj, pack=struct.pack): if self.bin: # If the int is small enough to fit in a signed 4-byte 2's-comp # format, we can store it more efficiently than the general # case. # First one- and two-byte unsigned ints: if obj >= 0: if obj <= 0xff: self.write(BININT1 + chr(obj)) return if obj <= 0xffff: self.write("%c%c%c" % (BININT2, obj&0xff, obj>>8)) return # Next check for 4-byte signed ints: high_bits = obj >> 31 # note that Python shift sign-extends if high_bits == 0 or high_bits == -1: # All high bits are copies of bit 2**31, so the value # fits in a 4-byte signed int. self.write(BININT + pack("= 2: bytes = encode_long(obj) n = len(bytes) if n < 256: self.write(LONG1 + chr(n) + bytes) else: self.write(LONG4 + pack("d', obj)) else: self.write(FLOAT + `obj` + '\n') dispatch[FloatType] = save_float def save_string(self, obj, pack=struct.pack): if self.bin: n = len(obj) if n < 256: self.write(SHORT_BINSTRING + chr(n) + obj) else: self.write(BINSTRING + pack("= 2: for element in obj: save(element) # Subtle. Same as in the big comment below. if id(obj) in memo: get = self.get(memo[id(obj)][0]) write(POP * n + get) else: write(_tuplesize2code[n]) self.memoize(obj) return # proto 0, or proto 1 and tuple isn't empty, or proto > 1 and tuple # has more than 3 elements. write(MARK) for element in obj: save(element) if n and id(obj) in memo: # Subtle. d was not in memo when we entered save_tuple(), so # the process of saving the tuple's elements must have saved # the tuple itself: the tuple is recursive. The proper action # now is to throw away everything we put on the stack, and # simply GET the tuple (it's already constructed). This check # could have been done in the "for element" loop instead, but # recursive tuples are a rare thing. get = self.get(memo[id(obj)][0]) if proto: write(POP_MARK + get) else: # proto 0 -- POP_MARK not available write(POP * (n+1) + get) return # No recursion (including the empty-tuple case for protocol 0). self.write(TUPLE) if obj: # No need to memoize empty tuple self.memoize(obj) dispatch[TupleType] = save_tuple # save_empty_tuple() isn't used by anything in Python 2.3. However, I # found a Pickler subclass in Zope3 that calls it, so it's not harmless # to remove it. def save_empty_tuple(self, obj): self.write(EMPTY_TUPLE) def save_list(self, obj): write = self.write save = self.save if self.bin: write(EMPTY_LIST) self.memoize(obj) n = len(obj) if n > 1: write(MARK) for element in obj: save(element) write(APPENDS) elif n: assert n == 1 save(obj[0]) write(APPEND) # else the list is empty, and we're already done else: # proto 0 -- can't use EMPTY_LIST or APPENDS write(MARK + LIST) self.memoize(obj) for element in obj: save(element) write(APPEND) dispatch[ListType] = save_list def save_dict(self, obj): write = self.write save = self.save items = obj.iteritems() if self.bin: write(EMPTY_DICT) self.memoize(obj) if len(obj) > 1: write(MARK) for key, value in items: save(key) save(value) write(SETITEMS) return # else (dict is empty or a singleton), fall through to the # SETITEM code at the end else: # proto 0 -- can't use EMPTY_DICT or SETITEMS write(MARK + DICT) self.memoize(obj) # proto 0 or len(obj) < 2 for key, value in items: save(key) save(value) write(SETITEM) dispatch[DictionaryType] = save_dict if not PyStringMap is None: dispatch[PyStringMap] = save_dict def save_inst(self, obj): cls = obj.__class__ memo = self.memo write = self.write save = self.save if hasattr(obj, '__getinitargs__'): args = obj.__getinitargs__() len(args) # XXX Assert it's a sequence _keep_alive(args, memo) else: args = () write(MARK) if self.bin: save(cls) for arg in args: save(arg) write(OBJ) else: for arg in args: save(arg) write(INST + cls.__module__ + '\n' + cls.__name__ + '\n') self.memoize(obj) try: getstate = obj.__getstate__ except AttributeError: stuff = obj.__dict__ else: stuff = getstate() _keep_alive(stuff, memo) save(stuff) write(BUILD) dispatch[InstanceType] = save_inst def save_global(self, obj, name=None, pack=struct.pack): write = self.write memo = self.memo if name is None: name = obj.__name__ try: module = obj.__module__ except AttributeError: module = whichmodule(obj, name) try: __import__(module) mod = sys.modules[module] klass = getattr(mod, name) except (ImportError, KeyError, AttributeError): raise PicklingError( "Can't pickle %r: it's not found as %s.%s" % (obj, module, name)) else: if klass is not obj: raise PicklingError( "Can't pickle %r: it's not the same object as %s.%s" % (obj, module, name)) if self.proto >= 2: code = extension_registry.get((module, name)) if code: assert code > 0 if code <= 0xff: write(EXT1 + chr(code)) elif code <= 0xffff: write("%c%c%c" % (EXT2, code&0xff, code>>8)) else: write(EXT4 + pack("d', self.read(8))[0]) dispatch[BINFLOAT] = load_binfloat def load_string(self): rep = self.readline()[:-1] for q in "\"'": # double or single quote if rep.startswith(q): if not rep.endswith(q): raise ValueError, "insecure string pickle" rep = rep[len(q):-len(q)] break else: raise ValueError, "insecure string pickle" self.append(rep.decode("string-escape")) dispatch[STRING] = load_string def load_binstring(self): len = mloads('i' + self.read(4)) self.append(self.read(len)) dispatch[BINSTRING] = load_binstring def load_unicode(self): self.append(unicode(self.readline()[:-1],'raw-unicode-escape')) dispatch[UNICODE] = load_unicode def load_binunicode(self): len = mloads('i' + self.read(4)) self.append(unicode(self.read(len),'utf-8')) dispatch[BINUNICODE] = load_binunicode def load_short_binstring(self): len = ord(self.read(1)) self.append(self.read(len)) dispatch[SHORT_BINSTRING] = load_short_binstring def load_tuple(self): k = self.marker() self.stack[k:] = [tuple(self.stack[k+1:])] dispatch[TUPLE] = load_tuple def load_empty_tuple(self): self.stack.append(()) dispatch[EMPTY_TUPLE] = load_empty_tuple def load_tuple1(self): self.stack[-1] = (self.stack[-1],) dispatch[TUPLE1] = load_tuple1 def load_tuple2(self): self.stack[-2:] = [(self.stack[-2], self.stack[-1])] dispatch[TUPLE2] = load_tuple2 def load_tuple3(self): self.stack[-3:] = [(self.stack[-3], self.stack[-2], self.stack[-1])] dispatch[TUPLE3] = load_tuple3 def load_empty_list(self): self.stack.append([]) dispatch[EMPTY_LIST] = load_empty_list def load_empty_dictionary(self): self.stack.append({}) dispatch[EMPTY_DICT] = load_empty_dictionary def load_list(self): k = self.marker() self.stack[k:] = [self.stack[k+1:]] dispatch[LIST] = load_list def load_dict(self): k = self.marker() d = {} items = self.stack[k+1:] for i in range(0, len(items), 2): key = items[i] value = items[i+1] d[key] = value self.stack[k:] = [d] dispatch[DICT] = load_dict # INST and OBJ differ only in how they get a class object. It's not # only sensible to do the rest in a common routine, the two routines # 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:] instantiated = 0 if (not args and type(klass) is ClassType and not hasattr(klass, "__getinitargs__")): try: value = _EmptyClass() value.__class__ = klass instantiated = 1 except RuntimeError: # In restricted execution, assignment to inst.__class__ is # prohibited pass if not instantiated: try: value = klass(*args) except TypeError, err: raise TypeError, "in constructor for %s: %s" % ( klass.__name__, str(err)), sys.exc_info()[2] self.append(value) def load_inst(self): module = self.readline()[:-1] name = self.readline()[:-1] klass = self.find_class(module, name) self._instantiate(klass, self.marker()) dispatch[INST] = 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) dispatch[OBJ] = load_obj def load_newobj(self): args = self.stack.pop() cls = self.stack[-1] obj = cls.__new__(cls, *args) self.stack[-1] = obj dispatch[NEWOBJ] = load_newobj def load_global(self): module = self.readline()[:-1] name = self.readline()[:-1] klass = self.find_class(module, name) self.append(klass) dispatch[GLOBAL] = load_global def load_ext1(self): code = ord(self.read(1)) self.get_extension(code) dispatch[EXT1] = load_ext1 def load_ext2(self): code = mloads('i' + self.read(2) + '\000\000') self.get_extension(code) dispatch[EXT2] = load_ext2 def load_ext4(self): code = mloads('i' + self.read(4)) self.get_extension(code) dispatch[EXT4] = load_ext4 def get_extension(self, code): nil = [] obj = extension_cache.get(code, nil) if obj is not nil: self.append(obj) return key = inverted_registry.get(code) if not key: raise ValueError("unregistered extension code %d" % code) obj = self.find_class(*key) extension_cache[code] = obj self.append(obj) def find_class(self, module, name): # Subclasses may override this __import__(module) mod = sys.modules[module] klass = getattr(mod, name) return klass def load_reduce(self): stack = self.stack args = stack.pop() func = stack[-1] if args is None: # A hack for Jim Fulton's ExtensionClass, now deprecated warnings.warn("__basicnew__ special case is deprecated", DeprecationWarning) value = func.__basicnew__() else: value = func(*args) stack[-1] = value dispatch[REDUCE] = load_reduce def load_pop(self): del self.stack[-1] dispatch[POP] = load_pop def load_pop_mark(self): k = self.marker() del self.stack[k:] dispatch[POP_MARK] = load_pop_mark def load_dup(self): self.append(self.stack[-1]) dispatch[DUP] = load_dup def load_get(self): self.append(self.memo[self.readline()[:-1]]) dispatch[GET] = load_get def load_binget(self): i = ord(self.read(1)) self.append(self.memo[`i`]) dispatch[BINGET] = load_binget def load_long_binget(self): i = mloads('i' + self.read(4)) self.append(self.memo[`i`]) dispatch[LONG_BINGET] = load_long_binget def load_put(self): self.memo[self.readline()[:-1]] = self.stack[-1] dispatch[PUT] = load_put def load_binput(self): i = ord(self.read(1)) self.memo[`i`] = self.stack[-1] dispatch[BINPUT] = load_binput def load_long_binput(self): i = mloads('i' + self.read(4)) self.memo[`i`] = self.stack[-1] dispatch[LONG_BINPUT] = load_long_binput def load_append(self): stack = self.stack value = stack.pop() list = stack[-1] list.append(value) dispatch[APPEND] = load_append def load_appends(self): stack = self.stack mark = self.marker() list = stack[mark - 1] list.extend(stack[mark + 1:]) del stack[mark:] dispatch[APPENDS] = load_appends def load_setitem(self): stack = self.stack value = stack.pop() key = stack.pop() dict = stack[-1] dict[key] = value dispatch[SETITEM] = 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:] dispatch[SETITEMS] = load_setitems def load_build(self): stack = self.stack state = stack.pop() inst = stack[-1] setstate = getattr(inst, "__setstate__", None) if setstate: setstate(state) return slotstate = None if isinstance(state, tuple) and len(state) == 2: state, slotstate = state if state: try: inst.__dict__.update(state) except RuntimeError: # XXX In restricted execution, the instance's __dict__ # is not accessible. Use the old way of unpickling # the instance variables. This is a semantic # difference when unpickling in restricted # vs. unrestricted modes. for k, v in state.items(): setattr(inst, k, v) if slotstate: for k, v in slotstate.items(): setattr(inst, k, v) dispatch[BUILD] = load_build def load_mark(self): self.append(self.mark) dispatch[MARK] = load_mark def load_stop(self): value = self.stack.pop() raise _Stop(value) dispatch[STOP] = load_stop # Helper class for load_inst/load_obj class _EmptyClass: pass # Encode/decode longs. def encode_long(x): r"""Encode a long to a two's complement little-ending binary string. >>> encode_long(255L) '\xff\x00' >>> encode_long(32767L) '\xff\x7f' >>> encode_long(-256L) '\x00\xff' >>> encode_long(-32768L) '\x00\x80' >>> encode_long(-128L) '\x80' >>> encode_long(127L) '\x7f' >>> """ # XXX This is still a quadratic algorithm. # Should use hex() to get started. digits = [] while not -128 <= x < 128: digits.append(x & 0xff) x >>= 8 digits.append(x & 0xff) return "".join(map(chr, digits)) def decode_long(data): r"""Decode a long from a two's complement little-endian binary string. >>> decode_long("\xff\x00") 255L >>> decode_long("\xff\x7f") 32767L >>> decode_long("\x00\xff") -256L >>> decode_long("\x00\x80") -32768L >>> decode_long("\x80") -128L >>> decode_long("\x7f") 127L """ # XXX This is quadratic too. x = 0L i = 0L for c in data: x |= long(ord(c)) << i i += 8L if data and ord(c) >= 0x80: x -= 1L << i return x # Shorthands try: from cStringIO import StringIO except ImportError: from StringIO import StringIO def dump(obj, file, proto=1): Pickler(file, proto).dump(obj) def dumps(obj, proto=1): file = StringIO() Pickler(file, proto).dump(obj) return file.getvalue() def load(file): return Unpickler(file).load() def loads(str): file = StringIO(str) return Unpickler(file).load() # Doctest def _test(): import doctest return doctest.testmod() if __name__ == "__main__": _test()