| """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 | |
| from copy_reg import _extension_registry, _inverted_registry, _extension_cache | |
| import marshal | |
| import sys | |
| import struct | |
| import re | |
| __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 | |
| # Keep in synch with cPickle. This is the highest protocol number we | |
| # know how to read. | |
| HIGHEST_PROTOCOL = 2 | |
| # 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, protocol=None): | |
| """This takes a file-like object for writing a pickle data stream. | |
| The optional protocol argument tells the pickler to use the | |
| given protocol; supported protocols are 0, 1, 2. The default | |
| protocol is 0, to be backwards compatible. (Protocol 0 is the | |
| only protocol that can be written to a file opened in text | |
| mode and read back successfully. When using a protocol higher | |
| than 0, make sure the file is opened in binary mode, both when | |
| pickling and unpickling.) | |
| Protocol 1 is more efficient than protocol 0; protocol 2 is | |
| more efficient than protocol 1. | |
| Specifying a negative protocol version selects the highest | |
| protocol version supported. The higher the protocol used, the | |
| more recent the version of Python needed to read the pickle | |
| produced. | |
| 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 protocol is None: | |
| protocol = 0 | |
| if protocol < 0: | |
| protocol = HIGHEST_PROTOCOL | |
| elif not 0 <= protocol <= HIGHEST_PROTOCOL: | |
| raise ValueError("pickle protocol must be <= %d" % HIGHEST_PROTOCOL) | |
| self.write = file.write | |
| self.memo = {} | |
| self.proto = int(protocol) | |
| self.bin = protocol >= 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.""" | |
| 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("<i", i) | |
| return PUT + repr(i) + '\n' | |
| # Return a GET (BINGET, LONG_BINGET) opcode string, with argument i. | |
| def get(self, i, pack=struct.pack): | |
| if self.bin: | |
| if i < 256: | |
| return BINGET + chr(i) | |
| else: | |
| return LONG_BINGET + pack("<i", i) | |
| return GET + repr(i) + '\n' | |
| def save(self, obj): | |
| # Check for persistent id (defined by a subclass) | |
| pid = self.persistent_id(obj) | |
| if pid: | |
| self.save_pers(pid) | |
| return | |
| # Check the memo | |
| x = self.memo.get(id(obj)) | |
| if x: | |
| self.write(self.get(x[0])) | |
| return | |
| # Check the type dispatch table | |
| t = type(obj) | |
| f = self.dispatch.get(t) | |
| if f: | |
| f(self, obj) # Call unbound method with explicit self | |
| return | |
| # Check for a class with a custom metaclass; treat as regular class | |
| try: | |
| issc = issubclass(t, TypeType) | |
| except TypeError: # t is not a class (old Boost; see SF #502085) | |
| issc = 0 | |
| if issc: | |
| self.save_global(obj) | |
| return | |
| # Check copy_reg.dispatch_table | |
| reduce = dispatch_table.get(t) | |
| if reduce: | |
| rv = reduce(obj) | |
| else: | |
| # Check for a __reduce_ex__ method, fall back to __reduce__ | |
| reduce = getattr(obj, "__reduce_ex__", None) | |
| if reduce: | |
| rv = reduce(self.proto) | |
| else: | |
| reduce = getattr(obj, "__reduce__", None) | |
| if reduce: | |
| rv = reduce() | |
| else: | |
| raise PicklingError("Can't pickle %r object: %r" % | |
| (t.__name__, 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 an appropriately sized tuple | |
| l = len(rv) | |
| if not (2 <= l <= 5): | |
| raise PicklingError("Tuple returned by %s must have " | |
| "two to five elements" % reduce) | |
| # Save the reduce() output and finally memoize the object | |
| self.save_reduce(obj=obj, *rv) | |
| 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, | |
| listitems=None, dictitems=None, obj=None): | |
| # This API is called by some subclasses | |
| # Assert that args is a tuple or None | |
| if not isinstance(args, TupleType): | |
| raise PicklingError("args from reduce() should be a tuple") | |
| # Assert that func is callable | |
| if not hasattr(func, '__call__'): | |
| raise PicklingError("func from reduce should be callable") | |
| save = self.save | |
| write = self.write | |
| # Protocol 2 special case: if func's name is __newobj__, use NEWOBJ | |
| if self.proto >= 2 and getattr(func, "__name__", "") == "__newobj__": | |
| # A __reduce__ implementation can direct protocol 2 to | |
| # use the more efficient NEWOBJ opcode, while still | |
| # allowing protocol 0 and 1 to work normally. For this to | |
| # work, the function returned by __reduce__ should be | |
| # called __newobj__, and its first argument should be a | |
| # new-style class. The implementation for __newobj__ | |
| # should be as follows, although pickle has no way to | |
| # verify this: | |
| # | |
| # def __newobj__(cls, *args): | |
| # return cls.__new__(cls, *args) | |
| # | |
| # Protocols 0 and 1 will pickle a reference to __newobj__, | |
| # while protocol 2 (and above) will pickle a reference to | |
| # cls, the remaining args tuple, and the NEWOBJ code, | |
| # which calls cls.__new__(cls, *args) at unpickling time | |
| # (see load_newobj below). If __reduce__ returns a | |
| # three-tuple, the state from the third tuple item will be | |
| # pickled regardless of the protocol, calling __setstate__ | |
| # at unpickling time (see load_build below). | |
| # | |
| # Note that no standard __newobj__ implementation exists; | |
| # you have to provide your own. This is to enforce | |
| # compatibility with Python 2.2 (pickles written using | |
| # protocol 0 or 1 in Python 2.3 should be unpicklable by | |
| # Python 2.2). | |
| cls = args[0] | |
| if not hasattr(cls, "__new__"): | |
| raise PicklingError( | |
| "args[0] from __newobj__ args has no __new__") | |
| if obj is not None and cls is not obj.__class__: | |
| raise PicklingError( | |
| "args[0] from __newobj__ args has the wrong class") | |
| args = args[1:] | |
| save(cls) | |
| save(args) | |
| write(NEWOBJ) | |
| else: | |
| save(func) | |
| save(args) | |
| write(REDUCE) | |
| if obj is not None: | |
| self.memoize(obj) | |
| # More new special cases (that work with older protocols as | |
| # well): when __reduce__ returns a tuple with 4 or 5 items, | |
| # the 4th and 5th item should be iterators that provide list | |
| # items and dict items (as (key, value) tuples), or None. | |
| if listitems is not None: | |
| self._batch_appends(listitems) | |
| if dictitems is not None: | |
| self._batch_setitems(dictitems) | |
| 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("<i", obj)) | |
| return | |
| # Text pickle, or int too big to fit in signed 4-byte format. | |
| self.write(INT + repr(obj) + '\n') | |
| dispatch[IntType] = save_int | |
| def save_long(self, obj, pack=struct.pack): | |
| if self.proto >= 2: | |
| bytes = encode_long(obj) | |
| n = len(bytes) | |
| if n < 256: | |
| self.write(LONG1 + chr(n) + bytes) | |
| else: | |
| self.write(LONG4 + pack("<i", n) + bytes) | |
| return | |
| self.write(LONG + repr(obj) + '\n') | |
| dispatch[LongType] = save_long | |
| def save_float(self, obj, pack=struct.pack): | |
| if self.bin: | |
| self.write(BINFLOAT + pack('>d', obj)) | |
| else: | |
| self.write(FLOAT + repr(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("<i", n) + obj) | |
| else: | |
| self.write(STRING + repr(obj) + '\n') | |
| self.memoize(obj) | |
| dispatch[StringType] = save_string | |
| def save_unicode(self, obj, pack=struct.pack): | |
| if self.bin: | |
| encoding = obj.encode('utf-8') | |
| n = len(encoding) | |
| self.write(BINUNICODE + pack("<i", n) + encoding) | |
| else: | |
| obj = obj.replace("\\", "\\u005c") | |
| obj = obj.replace("\n", "\\u000a") | |
| self.write(UNICODE + obj.encode('raw-unicode-escape') + '\n') | |
| self.memoize(obj) | |
| dispatch[UnicodeType] = save_unicode | |
| if StringType is UnicodeType: | |
| # This is true for Jython | |
| def save_string(self, obj, pack=struct.pack): | |
| unicode = obj.isunicode() | |
| if self.bin: | |
| if unicode: | |
| obj = obj.encode("utf-8") | |
| l = len(obj) | |
| if l < 256 and not unicode: | |
| self.write(SHORT_BINSTRING + chr(l) + obj) | |
| else: | |
| s = pack("<i", l) | |
| if unicode: | |
| self.write(BINUNICODE + s + obj) | |
| else: | |
| self.write(BINSTRING + s + obj) | |
| else: | |
| if unicode: | |
| obj = obj.replace("\\", "\\u005c") | |
| obj = obj.replace("\n", "\\u000a") | |
| obj = obj.encode('raw-unicode-escape') | |
| self.write(UNICODE + obj + '\n') | |
| else: | |
| self.write(STRING + repr(obj) + '\n') | |
| self.memoize(obj) | |
| dispatch[StringType] = save_string | |
| def save_tuple(self, obj): | |
| write = self.write | |
| proto = self.proto | |
| n = len(obj) | |
| if n == 0: | |
| if proto: | |
| write(EMPTY_TUPLE) | |
| else: | |
| write(MARK + TUPLE) | |
| return | |
| save = self.save | |
| memo = self.memo | |
| if n <= 3 and proto >= 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 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. | |
| self.write(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 | |
| if self.bin: | |
| write(EMPTY_LIST) | |
| else: # proto 0 -- can't use EMPTY_LIST | |
| write(MARK + LIST) | |
| self.memoize(obj) | |
| self._batch_appends(iter(obj)) | |
| dispatch[ListType] = save_list | |
| # Keep in synch with cPickle's BATCHSIZE. Nothing will break if it gets | |
| # out of synch, though. | |
| _BATCHSIZE = 1000 | |
| def _batch_appends(self, items): | |
| # Helper to batch up APPENDS sequences | |
| save = self.save | |
| write = self.write | |
| if not self.bin: | |
| for x in items: | |
| save(x) | |
| write(APPEND) | |
| return | |
| r = xrange(self._BATCHSIZE) | |
| while items is not None: | |
| tmp = [] | |
| for i in r: | |
| try: | |
| x = items.next() | |
| tmp.append(x) | |
| except StopIteration: | |
| items = None | |
| break | |
| n = len(tmp) | |
| if n > 1: | |
| write(MARK) | |
| for x in tmp: | |
| save(x) | |
| write(APPENDS) | |
| elif n: | |
| save(tmp[0]) | |
| write(APPEND) | |
| # else tmp is empty, and we're done | |
| def save_dict(self, obj): | |
| write = self.write | |
| if self.bin: | |
| write(EMPTY_DICT) | |
| else: # proto 0 -- can't use EMPTY_DICT | |
| write(MARK + DICT) | |
| self.memoize(obj) | |
| self._batch_setitems(obj.iteritems()) | |
| dispatch[DictionaryType] = save_dict | |
| if not PyStringMap is None: | |
| dispatch[PyStringMap] = save_dict | |
| def _batch_setitems(self, items): | |
| # Helper to batch up SETITEMS sequences; proto >= 1 only | |
| save = self.save | |
| write = self.write | |
| if not self.bin: | |
| for k, v in items: | |
| save(k) | |
| save(v) | |
| write(SETITEM) | |
| return | |
| r = xrange(self._BATCHSIZE) | |
| while items is not None: | |
| tmp = [] | |
| for i in r: | |
| try: | |
| tmp.append(items.next()) | |
| except StopIteration: | |
| items = None | |
| break | |
| n = len(tmp) | |
| if n > 1: | |
| write(MARK) | |
| for k, v in tmp: | |
| save(k) | |
| save(v) | |
| write(SETITEMS) | |
| elif n: | |
| k, v = tmp[0] | |
| save(k) | |
| save(v) | |
| write(SETITEM) | |
| # else tmp is empty, and we're done | |
| 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__ | |
| module = getattr(obj, "__module__", None) | |
| if module is None: | |
| 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("<i", code)) | |
| return | |
| write(GLOBAL + module + '\n' + name + '\n') | |
| self.memoize(obj) | |
| dispatch[ClassType] = save_global | |
| dispatch[FunctionType] = save_global | |
| dispatch[BuiltinFunctionType] = save_global | |
| dispatch[TypeType] = save_global | |
| # Pickling helpers | |
| def _keep_alive(x, memo): | |
| """Keeps a reference to the object x in the memo. | |
| Because we remember objects by their id, we have | |
| to assure that possibly temporary objects are kept | |
| alive by referencing them. | |
| We store a reference at the id of the memo, which should | |
| normally not be used unless someone tries to deepcopy | |
| the memo itself... | |
| """ | |
| try: | |
| memo[id(memo)].append(x) | |
| except KeyError: | |
| # aha, this is the first one :-) | |
| memo[id(memo)]=[x] | |
| # A cache for whichmodule(), mapping a function object to the name of | |
| # the module in which the function was found. | |
| classmap = {} # called classmap for backwards compatibility | |
| def whichmodule(func, funcname): | |
| """Figure out the module in which a function occurs. | |
| Search sys.modules for the module. | |
| Cache in classmap. | |
| Return a module name. | |
| If the function cannot be found, return "__main__". | |
| """ | |
| # Python functions should always get an __module__ from their globals. | |
| mod = getattr(func, "__module__", None) | |
| if mod is not None: | |
| return mod | |
| if func in classmap: | |
| return classmap[func] | |
| for name, module in sys.modules.items(): | |
| if module is None: | |
| continue # skip dummy package entries | |
| if name != '__main__' and getattr(module, funcname, None) is func: | |
| break | |
| else: | |
| name = '__main__' | |
| classmap[func] = name | |
| return name | |
| # Unpickling machinery | |
| class Unpickler: | |
| def __init__(self, file): | |
| """This takes a file-like object for reading a pickle data stream. | |
| The protocol version of the pickle is detected automatically, so no | |
| proto argument is needed. | |
| The file-like object must have two methods, a read() method that | |
| takes an integer argument, and a readline() method that requires no | |
| arguments. Both methods should return a string. Thus file-like | |
| object can be a file object opened for reading, a StringIO object, | |
| or any other custom object that meets this interface. | |
| """ | |
| self.readline = file.readline | |
| self.read = file.read | |
| self.memo = {} | |
| def load(self): | |
| """Read a pickled object representation from the open file. | |
| Return the reconstituted object hierarchy specified in the file. | |
| """ | |
| self.mark = object() # any new unique object | |
| self.stack = [] | |
| self.append = self.stack.append | |
| read = self.read | |
| dispatch = self.dispatch | |
| try: | |
| while 1: | |
| key = read(1) | |
| dispatch[key](self) | |
| except _Stop, 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 | |
| dispatch = {} | |
| def load_eof(self): | |
| raise EOFError | |
| dispatch[''] = load_eof | |
| def load_proto(self): | |
| proto = ord(self.read(1)) | |
| if not 0 <= proto <= 2: | |
| raise ValueError, "unsupported pickle protocol: %d" % proto | |
| dispatch[PROTO] = load_proto | |
| def load_persid(self): | |
| pid = self.readline()[:-1] | |
| self.append(self.persistent_load(pid)) | |
| dispatch[PERSID] = load_persid | |
| def load_binpersid(self): | |
| pid = self.stack.pop() | |
| self.append(self.persistent_load(pid)) | |
| dispatch[BINPERSID] = load_binpersid | |
| def load_none(self): | |
| self.append(None) | |
| dispatch[NONE] = load_none | |
| def load_false(self): | |
| self.append(False) | |
| dispatch[NEWFALSE] = load_false | |
| def load_true(self): | |
| self.append(True) | |
| dispatch[NEWTRUE] = load_true | |
| def load_int(self): | |
| data = self.readline() | |
| if data == FALSE[1:]: | |
| val = False | |
| elif data == TRUE[1:]: | |
| val = True | |
| else: | |
| try: | |
| val = int(data) | |
| except ValueError: | |
| val = long(data) | |
| self.append(val) | |
| dispatch[INT] = load_int | |
| def load_binint(self): | |
| self.append(mloads('i' + self.read(4))) | |
| dispatch[BININT] = load_binint | |
| def load_binint1(self): | |
| self.append(ord(self.read(1))) | |
| dispatch[BININT1] = load_binint1 | |
| def load_binint2(self): | |
| self.append(mloads('i' + self.read(2) + '\000\000')) | |
| dispatch[BININT2] = load_binint2 | |
| def load_long(self): | |
| self.append(long(self.readline()[:-1], 0)) | |
| dispatch[LONG] = load_long | |
| def load_long1(self): | |
| n = ord(self.read(1)) | |
| bytes = self.read(n) | |
| self.append(decode_long(bytes)) | |
| dispatch[LONG1] = load_long1 | |
| def load_long4(self): | |
| n = mloads('i' + self.read(4)) | |
| bytes = self.read(n) | |
| self.append(decode_long(bytes)) | |
| dispatch[LONG4] = load_long4 | |
| def load_float(self): | |
| self.append(float(self.readline()[:-1])) | |
| dispatch[FLOAT] = load_float | |
| def load_binfloat(self, unpack=struct.unpack): | |
| self.append(unpack('>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] | |
| 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[repr(i)]) | |
| dispatch[BINGET] = load_binget | |
| def load_long_binget(self): | |
| i = mloads('i' + self.read(4)) | |
| self.append(self.memo[repr(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[repr(i)] = self.stack[-1] | |
| dispatch[BINPUT] = load_binput | |
| def load_long_binput(self): | |
| i = mloads('i' + self.read(4)) | |
| self.memo[repr(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: | |
| d = inst.__dict__ | |
| try: | |
| for k, v in state.iteritems(): | |
| d[intern(k)] = v | |
| # keys in state don't have to be strings | |
| # don't blow up, but don't go out of our way | |
| except TypeError: | |
| d.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. | |
| # Note, however, that cPickle has never tried to do the | |
| # .update() business, and always uses | |
| # PyObject_SetItem(inst.__dict__, key, value) in a | |
| # loop over state.items(). | |
| 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 in linear time. | |
| import binascii as _binascii | |
| def encode_long(x): | |
| r"""Encode a long to a two's complement little-endian binary string. | |
| Note that 0L is a special case, returning an empty string, to save a | |
| byte in the LONG1 pickling context. | |
| >>> encode_long(0L) | |
| '' | |
| >>> 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' | |
| >>> | |
| """ | |
| if x == 0: | |
| return '' | |
| if x > 0: | |
| ashex = hex(x) | |
| assert ashex.startswith("0x") | |
| njunkchars = 2 + ashex.endswith('L') | |
| nibbles = len(ashex) - njunkchars | |
| if nibbles & 1: | |
| # need an even # of nibbles for unhexlify | |
| ashex = "0x0" + ashex[2:] | |
| elif int(ashex[2], 16) >= 8: | |
| # "looks negative", so need a byte of sign bits | |
| ashex = "0x00" + ashex[2:] | |
| else: | |
| # Build the 256's-complement: (1L << nbytes) + x. The trick is | |
| # to find the number of bytes in linear time (although that should | |
| # really be a constant-time task). | |
| ashex = hex(-x) | |
| assert ashex.startswith("0x") | |
| njunkchars = 2 + ashex.endswith('L') | |
| nibbles = len(ashex) - njunkchars | |
| if nibbles & 1: | |
| # Extend to a full byte. | |
| nibbles += 1 | |
| nbits = nibbles * 4 | |
| x += 1L << nbits | |
| assert x > 0 | |
| ashex = hex(x) | |
| njunkchars = 2 + ashex.endswith('L') | |
| newnibbles = len(ashex) - njunkchars | |
| if newnibbles < nibbles: | |
| ashex = "0x" + "0" * (nibbles - newnibbles) + ashex[2:] | |
| if int(ashex[2], 16) < 8: | |
| # "looks positive", so need a byte of sign bits | |
| ashex = "0xff" + ashex[2:] | |
| if ashex.endswith('L'): | |
| ashex = ashex[2:-1] | |
| else: | |
| ashex = ashex[2:] | |
| assert len(ashex) & 1 == 0, (x, ashex) | |
| binary = _binascii.unhexlify(ashex) | |
| return binary[::-1] | |
| def decode_long(data): | |
| r"""Decode a long from a two's complement little-endian binary string. | |
| >>> decode_long('') | |
| 0L | |
| >>> 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 | |
| """ | |
| nbytes = len(data) | |
| if nbytes == 0: | |
| return 0L | |
| ashex = _binascii.hexlify(data[::-1]) | |
| n = long(ashex, 16) # quadratic time before Python 2.3; linear now | |
| if data[-1] >= '\x80': | |
| n -= 1L << (nbytes * 8) | |
| return n | |
| # Shorthands | |
| try: | |
| from cStringIO import StringIO | |
| except ImportError: | |
| from StringIO import StringIO | |
| def dump(obj, file, protocol=None): | |
| Pickler(file, protocol).dump(obj) | |
| def dumps(obj, protocol=None): | |
| file = StringIO() | |
| Pickler(file, protocol).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() |