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authormonster <[email protected]>2022-07-07 14:41:37 +0300
committermonster <[email protected]>2022-07-07 14:41:37 +0300
commit06e5c21a835c0e923506c4ff27929f34e00761c2 (patch)
tree75efcbc6854ef9bd476eb8bf00cc5c900da436a2 /contrib/tools/python3/src/Lib/pickletools.py
parent03f024c4412e3aa613bb543cf1660176320ba8f4 (diff)
fix ya.make
Diffstat (limited to 'contrib/tools/python3/src/Lib/pickletools.py')
-rw-r--r--contrib/tools/python3/src/Lib/pickletools.py2890
1 files changed, 0 insertions, 2890 deletions
diff --git a/contrib/tools/python3/src/Lib/pickletools.py b/contrib/tools/python3/src/Lib/pickletools.py
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index 95706e746c9..00000000000
--- a/contrib/tools/python3/src/Lib/pickletools.py
+++ /dev/null
@@ -1,2890 +0,0 @@
-'''"Executable documentation" for the pickle module.
-
-Extensive comments about the pickle protocols and pickle-machine opcodes
-can be found here. Some functions meant for external use:
-
-genops(pickle)
- Generate all the opcodes in a pickle, as (opcode, arg, position) triples.
-
-dis(pickle, out=None, memo=None, indentlevel=4)
- Print a symbolic disassembly of a pickle.
-'''
-
-import codecs
-import io
-import pickle
-import re
-import sys
-
-__all__ = ['dis', 'genops', 'optimize']
-
-bytes_types = pickle.bytes_types
-
-# Other ideas:
-#
-# - A pickle verifier: read a pickle and check it exhaustively for
-# well-formedness. dis() does a lot of this already.
-#
-# - A protocol identifier: examine a pickle and return its protocol number
-# (== the highest .proto attr value among all the opcodes in the pickle).
-# dis() already prints this info at the end.
-#
-# - A pickle optimizer: for example, tuple-building code is sometimes more
-# elaborate than necessary, catering for the possibility that the tuple
-# is recursive. Or lots of times a PUT is generated that's never accessed
-# by a later GET.
-
-
-# "A pickle" is a program for a virtual pickle machine (PM, but more accurately
-# called an unpickling machine). It's a sequence of opcodes, interpreted by the
-# PM, building an arbitrarily complex Python object.
-#
-# For the most part, the PM is very simple: there are no looping, testing, or
-# conditional instructions, no arithmetic and no function calls. Opcodes are
-# executed once each, from first to last, until a STOP opcode is reached.
-#
-# The PM has two data areas, "the stack" and "the memo".
-#
-# Many opcodes push Python objects onto the stack; e.g., INT pushes a Python
-# integer object on the stack, whose value is gotten from a decimal string
-# literal immediately following the INT opcode in the pickle bytestream. Other
-# opcodes take Python objects off the stack. The result of unpickling is
-# whatever object is left on the stack when the final STOP opcode is executed.
-#
-# The memo is simply an array of objects, or it can be implemented as a dict
-# mapping little integers to objects. The memo serves as the PM's "long term
-# memory", and the little integers indexing the memo are akin to variable
-# names. Some opcodes pop a stack object into the memo at a given index,
-# and others push a memo object at a given index onto the stack again.
-#
-# At heart, that's all the PM has. Subtleties arise for these reasons:
-#
-# + Object identity. Objects can be arbitrarily complex, and subobjects
-# may be shared (for example, the list [a, a] refers to the same object a
-# twice). It can be vital that unpickling recreate an isomorphic object
-# graph, faithfully reproducing sharing.
-#
-# + Recursive objects. For example, after "L = []; L.append(L)", L is a
-# list, and L[0] is the same list. This is related to the object identity
-# point, and some sequences of pickle opcodes are subtle in order to
-# get the right result in all cases.
-#
-# + Things pickle doesn't know everything about. Examples of things pickle
-# does know everything about are Python's builtin scalar and container
-# types, like ints and tuples. They generally have opcodes dedicated to
-# them. For things like module references and instances of user-defined
-# classes, pickle's knowledge is limited. Historically, many enhancements
-# have been made to the pickle protocol in order to do a better (faster,
-# and/or more compact) job on those.
-#
-# + Backward compatibility and micro-optimization. As explained below,
-# pickle opcodes never go away, not even when better ways to do a thing
-# get invented. The repertoire of the PM just keeps growing over time.
-# For example, protocol 0 had two opcodes for building Python integers (INT
-# and LONG), protocol 1 added three more for more-efficient pickling of short
-# integers, and protocol 2 added two more for more-efficient pickling of
-# long integers (before protocol 2, the only ways to pickle a Python long
-# took time quadratic in the number of digits, for both pickling and
-# unpickling). "Opcode bloat" isn't so much a subtlety as a source of
-# wearying complication.
-#
-#
-# Pickle protocols:
-#
-# For compatibility, the meaning of a pickle opcode never changes. Instead new
-# pickle opcodes get added, and each version's unpickler can handle all the
-# pickle opcodes in all protocol versions to date. So old pickles continue to
-# be readable forever. The pickler can generally be told to restrict itself to
-# the subset of opcodes available under previous protocol versions too, so that
-# users can create pickles under the current version readable by older
-# versions. However, a pickle does not contain its version number embedded
-# within it. If an older unpickler tries to read a pickle using a later
-# protocol, the result is most likely an exception due to seeing an unknown (in
-# the older unpickler) opcode.
-#
-# The original pickle used what's now called "protocol 0", and what was called
-# "text mode" before Python 2.3. The entire pickle bytestream is made up of
-# printable 7-bit ASCII characters, plus the newline character, in protocol 0.
-# That's why it was called text mode. Protocol 0 is small and elegant, but
-# sometimes painfully inefficient.
-#
-# The second major set of additions is now called "protocol 1", and was called
-# "binary mode" before Python 2.3. This added many opcodes with arguments
-# consisting of arbitrary bytes, including NUL bytes and unprintable "high bit"
-# bytes. Binary mode pickles can be substantially smaller than equivalent
-# text mode pickles, and sometimes faster too; e.g., BININT represents a 4-byte
-# int as 4 bytes following the opcode, which is cheaper to unpickle than the
-# (perhaps) 11-character decimal string attached to INT. Protocol 1 also added
-# a number of opcodes that operate on many stack elements at once (like APPENDS
-# and SETITEMS), and "shortcut" opcodes (like EMPTY_DICT and EMPTY_TUPLE).
-#
-# The third major set of additions came in Python 2.3, and is called "protocol
-# 2". This added:
-#
-# - A better way to pickle instances of new-style classes (NEWOBJ).
-#
-# - A way for a pickle to identify its protocol (PROTO).
-#
-# - Time- and space- efficient pickling of long ints (LONG{1,4}).
-#
-# - Shortcuts for small tuples (TUPLE{1,2,3}}.
-#
-# - Dedicated opcodes for bools (NEWTRUE, NEWFALSE).
-#
-# - The "extension registry", a vector of popular objects that can be pushed
-# efficiently by index (EXT{1,2,4}). This is akin to the memo and GET, but
-# the registry contents are predefined (there's nothing akin to the memo's
-# PUT).
-#
-# Another independent change with Python 2.3 is the abandonment of any
-# pretense that it might be safe to load pickles received from untrusted
-# parties -- no sufficient security analysis has been done to guarantee
-# this and there isn't a use case that warrants the expense of such an
-# analysis.
-#
-# To this end, all tests for __safe_for_unpickling__ or for
-# copyreg.safe_constructors are removed from the unpickling code.
-# References to these variables in the descriptions below are to be seen
-# as describing unpickling in Python 2.2 and before.
-
-
-# Meta-rule: Descriptions are stored in instances of descriptor objects,
-# with plain constructors. No meta-language is defined from which
-# descriptors could be constructed. If you want, e.g., XML, write a little
-# program to generate XML from the objects.
-
-##############################################################################
-# Some pickle opcodes have an argument, following the opcode in the
-# bytestream. An argument is of a specific type, described by an instance
-# of ArgumentDescriptor. These are not to be confused with arguments taken
-# off the stack -- ArgumentDescriptor applies only to arguments embedded in
-# the opcode stream, immediately following an opcode.
-
-# Represents the number of bytes consumed by an argument delimited by the
-# next newline character.
-UP_TO_NEWLINE = -1
-
-# Represents the number of bytes consumed by a two-argument opcode where
-# the first argument gives the number of bytes in the second argument.
-TAKEN_FROM_ARGUMENT1 = -2 # num bytes is 1-byte unsigned int
-TAKEN_FROM_ARGUMENT4 = -3 # num bytes is 4-byte signed little-endian int
-TAKEN_FROM_ARGUMENT4U = -4 # num bytes is 4-byte unsigned little-endian int
-TAKEN_FROM_ARGUMENT8U = -5 # num bytes is 8-byte unsigned little-endian int
-
-class ArgumentDescriptor(object):
- __slots__ = (
- # name of descriptor record, also a module global name; a string
- 'name',
-
- # length of argument, in bytes; an int; UP_TO_NEWLINE and
- # TAKEN_FROM_ARGUMENT{1,4,8} are negative values for variable-length
- # cases
- 'n',
-
- # a function taking a file-like object, reading this kind of argument
- # from the object at the current position, advancing the current
- # position by n bytes, and returning the value of the argument
- 'reader',
-
- # human-readable docs for this arg descriptor; a string
- 'doc',
- )
-
- def __init__(self, name, n, reader, doc):
- assert isinstance(name, str)
- self.name = name
-
- assert isinstance(n, int) and (n >= 0 or
- n in (UP_TO_NEWLINE,
- TAKEN_FROM_ARGUMENT1,
- TAKEN_FROM_ARGUMENT4,
- TAKEN_FROM_ARGUMENT4U,
- TAKEN_FROM_ARGUMENT8U))
- self.n = n
-
- self.reader = reader
-
- assert isinstance(doc, str)
- self.doc = doc
-
-from struct import unpack as _unpack
-
-def read_uint1(f):
- r"""
- >>> import io
- >>> read_uint1(io.BytesIO(b'\xff'))
- 255
- """
-
- data = f.read(1)
- if data:
- return data[0]
- raise ValueError("not enough data in stream to read uint1")
-
-uint1 = ArgumentDescriptor(
- name='uint1',
- n=1,
- reader=read_uint1,
- doc="One-byte unsigned integer.")
-
-
-def read_uint2(f):
- r"""
- >>> import io
- >>> read_uint2(io.BytesIO(b'\xff\x00'))
- 255
- >>> read_uint2(io.BytesIO(b'\xff\xff'))
- 65535
- """
-
- data = f.read(2)
- if len(data) == 2:
- return _unpack("<H", data)[0]
- raise ValueError("not enough data in stream to read uint2")
-
-uint2 = ArgumentDescriptor(
- name='uint2',
- n=2,
- reader=read_uint2,
- doc="Two-byte unsigned integer, little-endian.")
-
-
-def read_int4(f):
- r"""
- >>> import io
- >>> read_int4(io.BytesIO(b'\xff\x00\x00\x00'))
- 255
- >>> read_int4(io.BytesIO(b'\x00\x00\x00\x80')) == -(2**31)
- True
- """
-
- data = f.read(4)
- if len(data) == 4:
- return _unpack("<i", data)[0]
- raise ValueError("not enough data in stream to read int4")
-
-int4 = ArgumentDescriptor(
- name='int4',
- n=4,
- reader=read_int4,
- doc="Four-byte signed integer, little-endian, 2's complement.")
-
-
-def read_uint4(f):
- r"""
- >>> import io
- >>> read_uint4(io.BytesIO(b'\xff\x00\x00\x00'))
- 255
- >>> read_uint4(io.BytesIO(b'\x00\x00\x00\x80')) == 2**31
- True
- """
-
- data = f.read(4)
- if len(data) == 4:
- return _unpack("<I", data)[0]
- raise ValueError("not enough data in stream to read uint4")
-
-uint4 = ArgumentDescriptor(
- name='uint4',
- n=4,
- reader=read_uint4,
- doc="Four-byte unsigned integer, little-endian.")
-
-
-def read_uint8(f):
- r"""
- >>> import io
- >>> read_uint8(io.BytesIO(b'\xff\x00\x00\x00\x00\x00\x00\x00'))
- 255
- >>> read_uint8(io.BytesIO(b'\xff' * 8)) == 2**64-1
- True
- """
-
- data = f.read(8)
- if len(data) == 8:
- return _unpack("<Q", data)[0]
- raise ValueError("not enough data in stream to read uint8")
-
-uint8 = ArgumentDescriptor(
- name='uint8',
- n=8,
- reader=read_uint8,
- doc="Eight-byte unsigned integer, little-endian.")
-
-
-def read_stringnl(f, decode=True, stripquotes=True):
- r"""
- >>> import io
- >>> read_stringnl(io.BytesIO(b"'abcd'\nefg\n"))
- 'abcd'
-
- >>> read_stringnl(io.BytesIO(b"\n"))
- Traceback (most recent call last):
- ...
- ValueError: no string quotes around b''
-
- >>> read_stringnl(io.BytesIO(b"\n"), stripquotes=False)
- ''
-
- >>> read_stringnl(io.BytesIO(b"''\n"))
- ''
-
- >>> read_stringnl(io.BytesIO(b'"abcd"'))
- Traceback (most recent call last):
- ...
- ValueError: no newline found when trying to read stringnl
-
- Embedded escapes are undone in the result.
- >>> read_stringnl(io.BytesIO(br"'a\n\\b\x00c\td'" + b"\n'e'"))
- 'a\n\\b\x00c\td'
- """
-
- data = f.readline()
- if not data.endswith(b'\n'):
- raise ValueError("no newline found when trying to read stringnl")
- data = data[:-1] # lose the newline
-
- if stripquotes:
- for q in (b'"', b"'"):
- if data.startswith(q):
- if not data.endswith(q):
- raise ValueError("strinq quote %r not found at both "
- "ends of %r" % (q, data))
- data = data[1:-1]
- break
- else:
- raise ValueError("no string quotes around %r" % data)
-
- if decode:
- data = codecs.escape_decode(data)[0].decode("ascii")
- return data
-
-stringnl = ArgumentDescriptor(
- name='stringnl',
- n=UP_TO_NEWLINE,
- reader=read_stringnl,
- doc="""A newline-terminated string.
-
- This is a repr-style string, with embedded escapes, and
- bracketing quotes.
- """)
-
-def read_stringnl_noescape(f):
- return read_stringnl(f, stripquotes=False)
-
-stringnl_noescape = ArgumentDescriptor(
- name='stringnl_noescape',
- n=UP_TO_NEWLINE,
- reader=read_stringnl_noescape,
- doc="""A newline-terminated string.
-
- This is a str-style string, without embedded escapes,
- or bracketing quotes. It should consist solely of
- printable ASCII characters.
- """)
-
-def read_stringnl_noescape_pair(f):
- r"""
- >>> import io
- >>> read_stringnl_noescape_pair(io.BytesIO(b"Queue\nEmpty\njunk"))
- 'Queue Empty'
- """
-
- return "%s %s" % (read_stringnl_noescape(f), read_stringnl_noescape(f))
-
-stringnl_noescape_pair = ArgumentDescriptor(
- name='stringnl_noescape_pair',
- n=UP_TO_NEWLINE,
- reader=read_stringnl_noescape_pair,
- doc="""A pair of newline-terminated strings.
-
- These are str-style strings, without embedded
- escapes, or bracketing quotes. They should
- consist solely of printable ASCII characters.
- The pair is returned as a single string, with
- a single blank separating the two strings.
- """)
-
-
-def read_string1(f):
- r"""
- >>> import io
- >>> read_string1(io.BytesIO(b"\x00"))
- ''
- >>> read_string1(io.BytesIO(b"\x03abcdef"))
- 'abc'
- """
-
- n = read_uint1(f)
- assert n >= 0
- data = f.read(n)
- if len(data) == n:
- return data.decode("latin-1")
- raise ValueError("expected %d bytes in a string1, but only %d remain" %
- (n, len(data)))
-
-string1 = ArgumentDescriptor(
- name="string1",
- n=TAKEN_FROM_ARGUMENT1,
- reader=read_string1,
- doc="""A counted string.
-
- The first argument is a 1-byte unsigned int giving the number
- of bytes in the string, and the second argument is that many
- bytes.
- """)
-
-
-def read_string4(f):
- r"""
- >>> import io
- >>> read_string4(io.BytesIO(b"\x00\x00\x00\x00abc"))
- ''
- >>> read_string4(io.BytesIO(b"\x03\x00\x00\x00abcdef"))
- 'abc'
- >>> read_string4(io.BytesIO(b"\x00\x00\x00\x03abcdef"))
- Traceback (most recent call last):
- ...
- ValueError: expected 50331648 bytes in a string4, but only 6 remain
- """
-
- n = read_int4(f)
- if n < 0:
- raise ValueError("string4 byte count < 0: %d" % n)
- data = f.read(n)
- if len(data) == n:
- return data.decode("latin-1")
- raise ValueError("expected %d bytes in a string4, but only %d remain" %
- (n, len(data)))
-
-string4 = ArgumentDescriptor(
- name="string4",
- n=TAKEN_FROM_ARGUMENT4,
- reader=read_string4,
- doc="""A counted string.
-
- The first argument is a 4-byte little-endian signed int giving
- the number of bytes in the string, and the second argument is
- that many bytes.
- """)
-
-
-def read_bytes1(f):
- r"""
- >>> import io
- >>> read_bytes1(io.BytesIO(b"\x00"))
- b''
- >>> read_bytes1(io.BytesIO(b"\x03abcdef"))
- b'abc'
- """
-
- n = read_uint1(f)
- assert n >= 0
- data = f.read(n)
- if len(data) == n:
- return data
- raise ValueError("expected %d bytes in a bytes1, but only %d remain" %
- (n, len(data)))
-
-bytes1 = ArgumentDescriptor(
- name="bytes1",
- n=TAKEN_FROM_ARGUMENT1,
- reader=read_bytes1,
- doc="""A counted bytes string.
-
- The first argument is a 1-byte unsigned int giving the number
- of bytes, and the second argument is that many bytes.
- """)
-
-
-def read_bytes4(f):
- r"""
- >>> import io
- >>> read_bytes4(io.BytesIO(b"\x00\x00\x00\x00abc"))
- b''
- >>> read_bytes4(io.BytesIO(b"\x03\x00\x00\x00abcdef"))
- b'abc'
- >>> read_bytes4(io.BytesIO(b"\x00\x00\x00\x03abcdef"))
- Traceback (most recent call last):
- ...
- ValueError: expected 50331648 bytes in a bytes4, but only 6 remain
- """
-
- n = read_uint4(f)
- assert n >= 0
- if n > sys.maxsize:
- raise ValueError("bytes4 byte count > sys.maxsize: %d" % n)
- data = f.read(n)
- if len(data) == n:
- return data
- raise ValueError("expected %d bytes in a bytes4, but only %d remain" %
- (n, len(data)))
-
-bytes4 = ArgumentDescriptor(
- name="bytes4",
- n=TAKEN_FROM_ARGUMENT4U,
- reader=read_bytes4,
- doc="""A counted bytes string.
-
- The first argument is a 4-byte little-endian unsigned int giving
- the number of bytes, and the second argument is that many bytes.
- """)
-
-
-def read_bytes8(f):
- r"""
- >>> import io, struct, sys
- >>> read_bytes8(io.BytesIO(b"\x00\x00\x00\x00\x00\x00\x00\x00abc"))
- b''
- >>> read_bytes8(io.BytesIO(b"\x03\x00\x00\x00\x00\x00\x00\x00abcdef"))
- b'abc'
- >>> bigsize8 = struct.pack("<Q", sys.maxsize//3)
- >>> read_bytes8(io.BytesIO(bigsize8 + b"abcdef")) #doctest: +ELLIPSIS
- Traceback (most recent call last):
- ...
- ValueError: expected ... bytes in a bytes8, but only 6 remain
- """
-
- n = read_uint8(f)
- assert n >= 0
- if n > sys.maxsize:
- raise ValueError("bytes8 byte count > sys.maxsize: %d" % n)
- data = f.read(n)
- if len(data) == n:
- return data
- raise ValueError("expected %d bytes in a bytes8, but only %d remain" %
- (n, len(data)))
-
-bytes8 = ArgumentDescriptor(
- name="bytes8",
- n=TAKEN_FROM_ARGUMENT8U,
- reader=read_bytes8,
- doc="""A counted bytes string.
-
- The first argument is an 8-byte little-endian unsigned int giving
- the number of bytes, and the second argument is that many bytes.
- """)
-
-
-def read_bytearray8(f):
- r"""
- >>> import io, struct, sys
- >>> read_bytearray8(io.BytesIO(b"\x00\x00\x00\x00\x00\x00\x00\x00abc"))
- bytearray(b'')
- >>> read_bytearray8(io.BytesIO(b"\x03\x00\x00\x00\x00\x00\x00\x00abcdef"))
- bytearray(b'abc')
- >>> bigsize8 = struct.pack("<Q", sys.maxsize//3)
- >>> read_bytearray8(io.BytesIO(bigsize8 + b"abcdef")) #doctest: +ELLIPSIS
- Traceback (most recent call last):
- ...
- ValueError: expected ... bytes in a bytearray8, but only 6 remain
- """
-
- n = read_uint8(f)
- assert n >= 0
- if n > sys.maxsize:
- raise ValueError("bytearray8 byte count > sys.maxsize: %d" % n)
- data = f.read(n)
- if len(data) == n:
- return bytearray(data)
- raise ValueError("expected %d bytes in a bytearray8, but only %d remain" %
- (n, len(data)))
-
-bytearray8 = ArgumentDescriptor(
- name="bytearray8",
- n=TAKEN_FROM_ARGUMENT8U,
- reader=read_bytearray8,
- doc="""A counted bytearray.
-
- The first argument is an 8-byte little-endian unsigned int giving
- the number of bytes, and the second argument is that many bytes.
- """)
-
-def read_unicodestringnl(f):
- r"""
- >>> import io
- >>> read_unicodestringnl(io.BytesIO(b"abc\\uabcd\njunk")) == 'abc\uabcd'
- True
- """
-
- data = f.readline()
- if not data.endswith(b'\n'):
- raise ValueError("no newline found when trying to read "
- "unicodestringnl")
- data = data[:-1] # lose the newline
- return str(data, 'raw-unicode-escape')
-
-unicodestringnl = ArgumentDescriptor(
- name='unicodestringnl',
- n=UP_TO_NEWLINE,
- reader=read_unicodestringnl,
- doc="""A newline-terminated Unicode string.
-
- This is raw-unicode-escape encoded, so consists of
- printable ASCII characters, and may contain embedded
- escape sequences.
- """)
-
-
-def read_unicodestring1(f):
- r"""
- >>> import io
- >>> s = 'abcd\uabcd'
- >>> enc = s.encode('utf-8')
- >>> enc
- b'abcd\xea\xaf\x8d'
- >>> n = bytes([len(enc)]) # little-endian 1-byte length
- >>> t = read_unicodestring1(io.BytesIO(n + enc + b'junk'))
- >>> s == t
- True
-
- >>> read_unicodestring1(io.BytesIO(n + enc[:-1]))
- Traceback (most recent call last):
- ...
- ValueError: expected 7 bytes in a unicodestring1, but only 6 remain
- """
-
- n = read_uint1(f)
- assert n >= 0
- data = f.read(n)
- if len(data) == n:
- return str(data, 'utf-8', 'surrogatepass')
- raise ValueError("expected %d bytes in a unicodestring1, but only %d "
- "remain" % (n, len(data)))
-
-unicodestring1 = ArgumentDescriptor(
- name="unicodestring1",
- n=TAKEN_FROM_ARGUMENT1,
- reader=read_unicodestring1,
- doc="""A counted Unicode string.
-
- The first argument is a 1-byte little-endian signed int
- giving the number of bytes in the string, and the second
- argument-- the UTF-8 encoding of the Unicode string --
- contains that many bytes.
- """)
-
-
-def read_unicodestring4(f):
- r"""
- >>> import io
- >>> s = 'abcd\uabcd'
- >>> enc = s.encode('utf-8')
- >>> enc
- b'abcd\xea\xaf\x8d'
- >>> n = bytes([len(enc), 0, 0, 0]) # little-endian 4-byte length
- >>> t = read_unicodestring4(io.BytesIO(n + enc + b'junk'))
- >>> s == t
- True
-
- >>> read_unicodestring4(io.BytesIO(n + enc[:-1]))
- Traceback (most recent call last):
- ...
- ValueError: expected 7 bytes in a unicodestring4, but only 6 remain
- """
-
- n = read_uint4(f)
- assert n >= 0
- if n > sys.maxsize:
- raise ValueError("unicodestring4 byte count > sys.maxsize: %d" % n)
- data = f.read(n)
- if len(data) == n:
- return str(data, 'utf-8', 'surrogatepass')
- raise ValueError("expected %d bytes in a unicodestring4, but only %d "
- "remain" % (n, len(data)))
-
-unicodestring4 = ArgumentDescriptor(
- name="unicodestring4",
- n=TAKEN_FROM_ARGUMENT4U,
- reader=read_unicodestring4,
- doc="""A counted Unicode string.
-
- The first argument is a 4-byte little-endian signed int
- giving the number of bytes in the string, and the second
- argument-- the UTF-8 encoding of the Unicode string --
- contains that many bytes.
- """)
-
-
-def read_unicodestring8(f):
- r"""
- >>> import io
- >>> s = 'abcd\uabcd'
- >>> enc = s.encode('utf-8')
- >>> enc
- b'abcd\xea\xaf\x8d'
- >>> n = bytes([len(enc)]) + b'\0' * 7 # little-endian 8-byte length
- >>> t = read_unicodestring8(io.BytesIO(n + enc + b'junk'))
- >>> s == t
- True
-
- >>> read_unicodestring8(io.BytesIO(n + enc[:-1]))
- Traceback (most recent call last):
- ...
- ValueError: expected 7 bytes in a unicodestring8, but only 6 remain
- """
-
- n = read_uint8(f)
- assert n >= 0
- if n > sys.maxsize:
- raise ValueError("unicodestring8 byte count > sys.maxsize: %d" % n)
- data = f.read(n)
- if len(data) == n:
- return str(data, 'utf-8', 'surrogatepass')
- raise ValueError("expected %d bytes in a unicodestring8, but only %d "
- "remain" % (n, len(data)))
-
-unicodestring8 = ArgumentDescriptor(
- name="unicodestring8",
- n=TAKEN_FROM_ARGUMENT8U,
- reader=read_unicodestring8,
- doc="""A counted Unicode string.
-
- The first argument is an 8-byte little-endian signed int
- giving the number of bytes in the string, and the second
- argument-- the UTF-8 encoding of the Unicode string --
- contains that many bytes.
- """)
-
-
-def read_decimalnl_short(f):
- r"""
- >>> import io
- >>> read_decimalnl_short(io.BytesIO(b"1234\n56"))
- 1234
-
- >>> read_decimalnl_short(io.BytesIO(b"1234L\n56"))
- Traceback (most recent call last):
- ...
- ValueError: invalid literal for int() with base 10: b'1234L'
- """
-
- s = read_stringnl(f, decode=False, stripquotes=False)
-
- # There's a hack for True and False here.
- if s == b"00":
- return False
- elif s == b"01":
- return True
-
- return int(s)
-
-def read_decimalnl_long(f):
- r"""
- >>> import io
-
- >>> read_decimalnl_long(io.BytesIO(b"1234L\n56"))
- 1234
-
- >>> read_decimalnl_long(io.BytesIO(b"123456789012345678901234L\n6"))
- 123456789012345678901234
- """
-
- s = read_stringnl(f, decode=False, stripquotes=False)
- if s[-1:] == b'L':
- s = s[:-1]
- return int(s)
-
-
-decimalnl_short = ArgumentDescriptor(
- name='decimalnl_short',
- n=UP_TO_NEWLINE,
- reader=read_decimalnl_short,
- doc="""A newline-terminated decimal integer literal.
-
- This never has a trailing 'L', and the integer fit
- in a short Python int on the box where the pickle
- was written -- but there's no guarantee it will fit
- in a short Python int on the box where the pickle
- is read.
- """)
-
-decimalnl_long = ArgumentDescriptor(
- name='decimalnl_long',
- n=UP_TO_NEWLINE,
- reader=read_decimalnl_long,
- doc="""A newline-terminated decimal integer literal.
-
- This has a trailing 'L', and can represent integers
- of any size.
- """)
-
-
-def read_floatnl(f):
- r"""
- >>> import io
- >>> read_floatnl(io.BytesIO(b"-1.25\n6"))
- -1.25
- """
- s = read_stringnl(f, decode=False, stripquotes=False)
- return float(s)
-
-floatnl = ArgumentDescriptor(
- name='floatnl',
- n=UP_TO_NEWLINE,
- reader=read_floatnl,
- doc="""A newline-terminated decimal floating literal.
-
- In general this requires 17 significant digits for roundtrip
- identity, and pickling then unpickling infinities, NaNs, and
- minus zero doesn't work across boxes, or on some boxes even
- on itself (e.g., Windows can't read the strings it produces
- for infinities or NaNs).
- """)
-
-def read_float8(f):
- r"""
- >>> import io, struct
- >>> raw = struct.pack(">d", -1.25)
- >>> raw
- b'\xbf\xf4\x00\x00\x00\x00\x00\x00'
- >>> read_float8(io.BytesIO(raw + b"\n"))
- -1.25
- """
-
- data = f.read(8)
- if len(data) == 8:
- return _unpack(">d", data)[0]
- raise ValueError("not enough data in stream to read float8")
-
-
-float8 = ArgumentDescriptor(
- name='float8',
- n=8,
- reader=read_float8,
- doc="""An 8-byte binary representation of a float, big-endian.
-
- The format is unique to Python, and shared with the struct
- module (format string '>d') "in theory" (the struct and pickle
- implementations don't share the code -- they should). It's
- strongly related to the IEEE-754 double format, and, in normal
- cases, is in fact identical to the big-endian 754 double format.
- On other boxes the dynamic range is limited to that of a 754
- double, and "add a half and chop" rounding is used to reduce
- the precision to 53 bits. However, even on a 754 box,
- infinities, NaNs, and minus zero may not be handled correctly
- (may not survive roundtrip pickling intact).
- """)
-
-# Protocol 2 formats
-
-from pickle import decode_long
-
-def read_long1(f):
- r"""
- >>> import io
- >>> read_long1(io.BytesIO(b"\x00"))
- 0
- >>> read_long1(io.BytesIO(b"\x02\xff\x00"))
- 255
- >>> read_long1(io.BytesIO(b"\x02\xff\x7f"))
- 32767
- >>> read_long1(io.BytesIO(b"\x02\x00\xff"))
- -256
- >>> read_long1(io.BytesIO(b"\x02\x00\x80"))
- -32768
- """
-
- n = read_uint1(f)
- data = f.read(n)
- if len(data) != n:
- raise ValueError("not enough data in stream to read long1")
- return decode_long(data)
-
-long1 = ArgumentDescriptor(
- name="long1",
- n=TAKEN_FROM_ARGUMENT1,
- reader=read_long1,
- doc="""A binary long, little-endian, using 1-byte size.
-
- This first reads one byte as an unsigned size, then reads that
- many bytes and interprets them as a little-endian 2's-complement long.
- If the size is 0, that's taken as a shortcut for the long 0L.
- """)
-
-def read_long4(f):
- r"""
- >>> import io
- >>> read_long4(io.BytesIO(b"\x02\x00\x00\x00\xff\x00"))
- 255
- >>> read_long4(io.BytesIO(b"\x02\x00\x00\x00\xff\x7f"))
- 32767
- >>> read_long4(io.BytesIO(b"\x02\x00\x00\x00\x00\xff"))
- -256
- >>> read_long4(io.BytesIO(b"\x02\x00\x00\x00\x00\x80"))
- -32768
- >>> read_long1(io.BytesIO(b"\x00\x00\x00\x00"))
- 0
- """
-
- n = read_int4(f)
- if n < 0:
- raise ValueError("long4 byte count < 0: %d" % n)
- data = f.read(n)
- if len(data) != n:
- raise ValueError("not enough data in stream to read long4")
- return decode_long(data)
-
-long4 = ArgumentDescriptor(
- name="long4",
- n=TAKEN_FROM_ARGUMENT4,
- reader=read_long4,
- doc="""A binary representation of a long, little-endian.
-
- This first reads four bytes as a signed size (but requires the
- size to be >= 0), then reads that many bytes and interprets them
- as a little-endian 2's-complement long. If the size is 0, that's taken
- as a shortcut for the int 0, although LONG1 should really be used
- then instead (and in any case where # of bytes < 256).
- """)
-
-
-##############################################################################
-# Object descriptors. The stack used by the pickle machine holds objects,
-# and in the stack_before and stack_after attributes of OpcodeInfo
-# descriptors we need names to describe the various types of objects that can
-# appear on the stack.
-
-class StackObject(object):
- __slots__ = (
- # name of descriptor record, for info only
- 'name',
-
- # type of object, or tuple of type objects (meaning the object can
- # be of any type in the tuple)
- 'obtype',
-
- # human-readable docs for this kind of stack object; a string
- 'doc',
- )
-
- def __init__(self, name, obtype, doc):
- assert isinstance(name, str)
- self.name = name
-
- assert isinstance(obtype, type) or isinstance(obtype, tuple)
- if isinstance(obtype, tuple):
- for contained in obtype:
- assert isinstance(contained, type)
- self.obtype = obtype
-
- assert isinstance(doc, str)
- self.doc = doc
-
- def __repr__(self):
- return self.name
-
-
-pyint = pylong = StackObject(
- name='int',
- obtype=int,
- doc="A Python integer object.")
-
-pyinteger_or_bool = StackObject(
- name='int_or_bool',
- obtype=(int, bool),
- doc="A Python integer or boolean object.")
-
-pybool = StackObject(
- name='bool',
- obtype=bool,
- doc="A Python boolean object.")
-
-pyfloat = StackObject(
- name='float',
- obtype=float,
- doc="A Python float object.")
-
-pybytes_or_str = pystring = StackObject(
- name='bytes_or_str',
- obtype=(bytes, str),
- doc="A Python bytes or (Unicode) string object.")
-
-pybytes = StackObject(
- name='bytes',
- obtype=bytes,
- doc="A Python bytes object.")
-
-pybytearray = StackObject(
- name='bytearray',
- obtype=bytearray,
- doc="A Python bytearray object.")
-
-pyunicode = StackObject(
- name='str',
- obtype=str,
- doc="A Python (Unicode) string object.")
-
-pynone = StackObject(
- name="None",
- obtype=type(None),
- doc="The Python None object.")
-
-pytuple = StackObject(
- name="tuple",
- obtype=tuple,
- doc="A Python tuple object.")
-
-pylist = StackObject(
- name="list",
- obtype=list,
- doc="A Python list object.")
-
-pydict = StackObject(
- name="dict",
- obtype=dict,
- doc="A Python dict object.")
-
-pyset = StackObject(
- name="set",
- obtype=set,
- doc="A Python set object.")
-
-pyfrozenset = StackObject(
- name="frozenset",
- obtype=set,
- doc="A Python frozenset object.")
-
-pybuffer = StackObject(
- name='buffer',
- obtype=object,
- doc="A Python buffer-like object.")
-
-anyobject = StackObject(
- name='any',
- obtype=object,
- doc="Any kind of object whatsoever.")
-
-markobject = StackObject(
- name="mark",
- obtype=StackObject,
- doc="""'The mark' is a unique object.
-
-Opcodes that operate on a variable number of objects
-generally don't embed the count of objects in the opcode,
-or pull it off the stack. Instead the MARK opcode is used
-to push a special marker object on the stack, and then
-some other opcodes grab all the objects from the top of
-the stack down to (but not including) the topmost marker
-object.
-""")
-
-stackslice = StackObject(
- name="stackslice",
- obtype=StackObject,
- doc="""An object representing a contiguous slice of the stack.
-
-This is used in conjunction with markobject, to represent all
-of the stack following the topmost markobject. For example,
-the POP_MARK opcode changes the stack from
-
- [..., markobject, stackslice]
-to
- [...]
-
-No matter how many object are on the stack after the topmost
-markobject, POP_MARK gets rid of all of them (including the
-topmost markobject too).
-""")
-
-##############################################################################
-# Descriptors for pickle opcodes.
-
-class OpcodeInfo(object):
-
- __slots__ = (
- # symbolic name of opcode; a string
- 'name',
-
- # the code used in a bytestream to represent the opcode; a
- # one-character string
- 'code',
-
- # If the opcode has an argument embedded in the byte string, an
- # instance of ArgumentDescriptor specifying its type. Note that
- # arg.reader(s) can be used to read and decode the argument from
- # the bytestream s, and arg.doc documents the format of the raw
- # argument bytes. If the opcode doesn't have an argument embedded
- # in the bytestream, arg should be None.
- 'arg',
-
- # what the stack looks like before this opcode runs; a list
- 'stack_before',
-
- # what the stack looks like after this opcode runs; a list
- 'stack_after',
-
- # the protocol number in which this opcode was introduced; an int
- 'proto',
-
- # human-readable docs for this opcode; a string
- 'doc',
- )
-
- def __init__(self, name, code, arg,
- stack_before, stack_after, proto, doc):
- assert isinstance(name, str)
- self.name = name
-
- assert isinstance(code, str)
- assert len(code) == 1
- self.code = code
-
- assert arg is None or isinstance(arg, ArgumentDescriptor)
- self.arg = arg
-
- assert isinstance(stack_before, list)
- for x in stack_before:
- assert isinstance(x, StackObject)
- self.stack_before = stack_before
-
- assert isinstance(stack_after, list)
- for x in stack_after:
- assert isinstance(x, StackObject)
- self.stack_after = stack_after
-
- assert isinstance(proto, int) and 0 <= proto <= pickle.HIGHEST_PROTOCOL
- self.proto = proto
-
- assert isinstance(doc, str)
- self.doc = doc
-
-I = OpcodeInfo
-opcodes = [
-
- # Ways to spell integers.
-
- I(name='INT',
- code='I',
- arg=decimalnl_short,
- stack_before=[],
- stack_after=[pyinteger_or_bool],
- proto=0,
- doc="""Push an integer or bool.
-
- The argument is a newline-terminated decimal literal string.
-
- The intent may have been that this always fit in a short Python int,
- but INT can be generated in pickles written on a 64-bit box that
- require a Python long on a 32-bit box. The difference between this
- and LONG then is that INT skips a trailing 'L', and produces a short
- int whenever possible.
-
- Another difference is due to that, when bool was introduced as a
- distinct type in 2.3, builtin names True and False were also added to
- 2.2.2, mapping to ints 1 and 0. For compatibility in both directions,
- True gets pickled as INT + "I01\\n", and False as INT + "I00\\n".
- Leading zeroes are never produced for a genuine integer. The 2.3
- (and later) unpicklers special-case these and return bool instead;
- earlier unpicklers ignore the leading "0" and return the int.
- """),
-
- I(name='BININT',
- code='J',
- arg=int4,
- stack_before=[],
- stack_after=[pyint],
- proto=1,
- doc="""Push a four-byte signed integer.
-
- This handles the full range of Python (short) integers on a 32-bit
- box, directly as binary bytes (1 for the opcode and 4 for the integer).
- If the integer is non-negative and fits in 1 or 2 bytes, pickling via
- BININT1 or BININT2 saves space.
- """),
-
- I(name='BININT1',
- code='K',
- arg=uint1,
- stack_before=[],
- stack_after=[pyint],
- proto=1,
- doc="""Push a one-byte unsigned integer.
-
- This is a space optimization for pickling very small non-negative ints,
- in range(256).
- """),
-
- I(name='BININT2',
- code='M',
- arg=uint2,
- stack_before=[],
- stack_after=[pyint],
- proto=1,
- doc="""Push a two-byte unsigned integer.
-
- This is a space optimization for pickling small positive ints, in
- range(256, 2**16). Integers in range(256) can also be pickled via
- BININT2, but BININT1 instead saves a byte.
- """),
-
- I(name='LONG',
- code='L',
- arg=decimalnl_long,
- stack_before=[],
- stack_after=[pyint],
- proto=0,
- doc="""Push a long integer.
-
- The same as INT, except that the literal ends with 'L', and always
- unpickles to a Python long. There doesn't seem a real purpose to the
- trailing 'L'.
-
- Note that LONG takes time quadratic in the number of digits when
- unpickling (this is simply due to the nature of decimal->binary
- conversion). Proto 2 added linear-time (in C; still quadratic-time
- in Python) LONG1 and LONG4 opcodes.
- """),
-
- I(name="LONG1",
- code='\x8a',
- arg=long1,
- stack_before=[],
- stack_after=[pyint],
- proto=2,
- doc="""Long integer using one-byte length.
-
- A more efficient encoding of a Python long; the long1 encoding
- says it all."""),
-
- I(name="LONG4",
- code='\x8b',
- arg=long4,
- stack_before=[],
- stack_after=[pyint],
- proto=2,
- doc="""Long integer using found-byte length.
-
- A more efficient encoding of a Python long; the long4 encoding
- says it all."""),
-
- # Ways to spell strings (8-bit, not Unicode).
-
- I(name='STRING',
- code='S',
- arg=stringnl,
- stack_before=[],
- stack_after=[pybytes_or_str],
- proto=0,
- doc="""Push a Python string object.
-
- The argument is a repr-style string, with bracketing quote characters,
- and perhaps embedded escapes. The argument extends until the next
- newline character. These are usually decoded into a str instance
- using the encoding given to the Unpickler constructor. or the default,
- 'ASCII'. If the encoding given was 'bytes' however, they will be
- decoded as bytes object instead.
- """),
-
- I(name='BINSTRING',
- code='T',
- arg=string4,
- stack_before=[],
- stack_after=[pybytes_or_str],
- proto=1,
- doc="""Push a Python string object.
-
- There are two arguments: the first is a 4-byte little-endian
- signed int giving the number of bytes in the string, and the
- second is that many bytes, which are taken literally as the string
- content. These are usually decoded into a str instance using the
- encoding given to the Unpickler constructor. or the default,
- 'ASCII'. If the encoding given was 'bytes' however, they will be
- decoded as bytes object instead.
- """),
-
- I(name='SHORT_BINSTRING',
- code='U',
- arg=string1,
- stack_before=[],
- stack_after=[pybytes_or_str],
- proto=1,
- doc="""Push a Python string object.
-
- There are two arguments: the first is a 1-byte unsigned int giving
- the number of bytes in the string, and the second is that many
- bytes, which are taken literally as the string content. These are
- usually decoded into a str instance using the encoding given to
- the Unpickler constructor. or the default, 'ASCII'. If the
- encoding given was 'bytes' however, they will be decoded as bytes
- object instead.
- """),
-
- # Bytes (protocol 3 and higher)
-
- I(name='BINBYTES',
- code='B',
- arg=bytes4,
- stack_before=[],
- stack_after=[pybytes],
- proto=3,
- doc="""Push a Python bytes object.
-
- There are two arguments: the first is a 4-byte little-endian unsigned int
- giving the number of bytes, and the second is that many bytes, which are
- taken literally as the bytes content.
- """),
-
- I(name='SHORT_BINBYTES',
- code='C',
- arg=bytes1,
- stack_before=[],
- stack_after=[pybytes],
- proto=3,
- doc="""Push a Python bytes object.
-
- There are two arguments: the first is a 1-byte unsigned int giving
- the number of bytes, and the second is that many bytes, which are taken
- literally as the string content.
- """),
-
- I(name='BINBYTES8',
- code='\x8e',
- arg=bytes8,
- stack_before=[],
- stack_after=[pybytes],
- proto=4,
- doc="""Push a Python bytes object.
-
- There are two arguments: the first is an 8-byte unsigned int giving
- the number of bytes in the string, and the second is that many bytes,
- which are taken literally as the string content.
- """),
-
- # Bytearray (protocol 5 and higher)
-
- I(name='BYTEARRAY8',
- code='\x96',
- arg=bytearray8,
- stack_before=[],
- stack_after=[pybytearray],
- proto=5,
- doc="""Push a Python bytearray object.
-
- There are two arguments: the first is an 8-byte unsigned int giving
- the number of bytes in the bytearray, and the second is that many bytes,
- which are taken literally as the bytearray content.
- """),
-
- # Out-of-band buffer (protocol 5 and higher)
-
- I(name='NEXT_BUFFER',
- code='\x97',
- arg=None,
- stack_before=[],
- stack_after=[pybuffer],
- proto=5,
- doc="Push an out-of-band buffer object."),
-
- I(name='READONLY_BUFFER',
- code='\x98',
- arg=None,
- stack_before=[pybuffer],
- stack_after=[pybuffer],
- proto=5,
- doc="Make an out-of-band buffer object read-only."),
-
- # Ways to spell None.
-
- I(name='NONE',
- code='N',
- arg=None,
- stack_before=[],
- stack_after=[pynone],
- proto=0,
- doc="Push None on the stack."),
-
- # Ways to spell bools, starting with proto 2. See INT for how this was
- # done before proto 2.
-
- I(name='NEWTRUE',
- code='\x88',
- arg=None,
- stack_before=[],
- stack_after=[pybool],
- proto=2,
- doc="Push True onto the stack."),
-
- I(name='NEWFALSE',
- code='\x89',
- arg=None,
- stack_before=[],
- stack_after=[pybool],
- proto=2,
- doc="Push False onto the stack."),
-
- # Ways to spell Unicode strings.
-
- I(name='UNICODE',
- code='V',
- arg=unicodestringnl,
- stack_before=[],
- stack_after=[pyunicode],
- proto=0, # this may be pure-text, but it's a later addition
- doc="""Push a Python Unicode string object.
-
- The argument is a raw-unicode-escape encoding of a Unicode string,
- and so may contain embedded escape sequences. The argument extends
- until the next newline character.
- """),
-
- I(name='SHORT_BINUNICODE',
- code='\x8c',
- arg=unicodestring1,
- stack_before=[],
- stack_after=[pyunicode],
- proto=4,
- doc="""Push a Python Unicode string object.
-
- There are two arguments: the first is a 1-byte little-endian signed int
- giving the number of bytes in the string. The second is that many
- bytes, and is the UTF-8 encoding of the Unicode string.
- """),
-
- I(name='BINUNICODE',
- code='X',
- arg=unicodestring4,
- stack_before=[],
- stack_after=[pyunicode],
- proto=1,
- doc="""Push a Python Unicode string object.
-
- There are two arguments: the first is a 4-byte little-endian unsigned int
- giving the number of bytes in the string. The second is that many
- bytes, and is the UTF-8 encoding of the Unicode string.
- """),
-
- I(name='BINUNICODE8',
- code='\x8d',
- arg=unicodestring8,
- stack_before=[],
- stack_after=[pyunicode],
- proto=4,
- doc="""Push a Python Unicode string object.
-
- There are two arguments: the first is an 8-byte little-endian signed int
- giving the number of bytes in the string. The second is that many
- bytes, and is the UTF-8 encoding of the Unicode string.
- """),
-
- # Ways to spell floats.
-
- I(name='FLOAT',
- code='F',
- arg=floatnl,
- stack_before=[],
- stack_after=[pyfloat],
- proto=0,
- doc="""Newline-terminated decimal float literal.
-
- The argument is repr(a_float), and in general requires 17 significant
- digits for roundtrip conversion to be an identity (this is so for
- IEEE-754 double precision values, which is what Python float maps to
- on most boxes).
-
- In general, FLOAT cannot be used to transport infinities, NaNs, or
- minus zero across boxes (or even on a single box, if the platform C
- library can't read the strings it produces for such things -- Windows
- is like that), but may do less damage than BINFLOAT on boxes with
- greater precision or dynamic range than IEEE-754 double.
- """),
-
- I(name='BINFLOAT',
- code='G',
- arg=float8,
- stack_before=[],
- stack_after=[pyfloat],
- proto=1,
- doc="""Float stored in binary form, with 8 bytes of data.
-
- This generally requires less than half the space of FLOAT encoding.
- In general, BINFLOAT cannot be used to transport infinities, NaNs, or
- minus zero, raises an exception if the exponent exceeds the range of
- an IEEE-754 double, and retains no more than 53 bits of precision (if
- there are more than that, "add a half and chop" rounding is used to
- cut it back to 53 significant bits).
- """),
-
- # Ways to build lists.
-
- I(name='EMPTY_LIST',
- code=']',
- arg=None,
- stack_before=[],
- stack_after=[pylist],
- proto=1,
- doc="Push an empty list."),
-
- I(name='APPEND',
- code='a',
- arg=None,
- stack_before=[pylist, anyobject],
- stack_after=[pylist],
- proto=0,
- doc="""Append an object to a list.
-
- Stack before: ... pylist anyobject
- Stack after: ... pylist+[anyobject]
-
- although pylist is really extended in-place.
- """),
-
- I(name='APPENDS',
- code='e',
- arg=None,
- stack_before=[pylist, markobject, stackslice],
- stack_after=[pylist],
- proto=1,
- doc="""Extend a list by a slice of stack objects.
-
- Stack before: ... pylist markobject stackslice
- Stack after: ... pylist+stackslice
-
- although pylist is really extended in-place.
- """),
-
- I(name='LIST',
- code='l',
- arg=None,
- stack_before=[markobject, stackslice],
- stack_after=[pylist],
- proto=0,
- doc="""Build a list out of the topmost stack slice, after markobject.
-
- All the stack entries following the topmost markobject are placed into
- a single Python list, which single list object replaces all of the
- stack from the topmost markobject onward. For example,
-
- Stack before: ... markobject 1 2 3 'abc'
- Stack after: ... [1, 2, 3, 'abc']
- """),
-
- # Ways to build tuples.
-
- I(name='EMPTY_TUPLE',
- code=')',
- arg=None,
- stack_before=[],
- stack_after=[pytuple],
- proto=1,
- doc="Push an empty tuple."),
-
- I(name='TUPLE',
- code='t',
- arg=None,
- stack_before=[markobject, stackslice],
- stack_after=[pytuple],
- proto=0,
- doc="""Build a tuple out of the topmost stack slice, after markobject.
-
- All the stack entries following the topmost markobject are placed into
- a single Python tuple, which single tuple object replaces all of the
- stack from the topmost markobject onward. For example,
-
- Stack before: ... markobject 1 2 3 'abc'
- Stack after: ... (1, 2, 3, 'abc')
- """),
-
- I(name='TUPLE1',
- code='\x85',
- arg=None,
- stack_before=[anyobject],
- stack_after=[pytuple],
- proto=2,
- doc="""Build a one-tuple out of the topmost item on the stack.
-
- This code pops one value off the stack and pushes a tuple of
- length 1 whose one item is that value back onto it. In other
- words:
-
- stack[-1] = tuple(stack[-1:])
- """),
-
- I(name='TUPLE2',
- code='\x86',
- arg=None,
- stack_before=[anyobject, anyobject],
- stack_after=[pytuple],
- proto=2,
- doc="""Build a two-tuple out of the top two items on the stack.
-
- This code pops two values off the stack and pushes a tuple of
- length 2 whose items are those values back onto it. In other
- words:
-
- stack[-2:] = [tuple(stack[-2:])]
- """),
-
- I(name='TUPLE3',
- code='\x87',
- arg=None,
- stack_before=[anyobject, anyobject, anyobject],
- stack_after=[pytuple],
- proto=2,
- doc="""Build a three-tuple out of the top three items on the stack.
-
- This code pops three values off the stack and pushes a tuple of
- length 3 whose items are those values back onto it. In other
- words:
-
- stack[-3:] = [tuple(stack[-3:])]
- """),
-
- # Ways to build dicts.
-
- I(name='EMPTY_DICT',
- code='}',
- arg=None,
- stack_before=[],
- stack_after=[pydict],
- proto=1,
- doc="Push an empty dict."),
-
- I(name='DICT',
- code='d',
- arg=None,
- stack_before=[markobject, stackslice],
- stack_after=[pydict],
- proto=0,
- doc="""Build a dict out of the topmost stack slice, after markobject.
-
- All the stack entries following the topmost markobject are placed into
- a single Python dict, which single dict object replaces all of the
- stack from the topmost markobject onward. The stack slice alternates
- key, value, key, value, .... For example,
-
- Stack before: ... markobject 1 2 3 'abc'
- Stack after: ... {1: 2, 3: 'abc'}
- """),
-
- I(name='SETITEM',
- code='s',
- arg=None,
- stack_before=[pydict, anyobject, anyobject],
- stack_after=[pydict],
- proto=0,
- doc="""Add a key+value pair to an existing dict.
-
- Stack before: ... pydict key value
- Stack after: ... pydict
-
- where pydict has been modified via pydict[key] = value.
- """),
-
- I(name='SETITEMS',
- code='u',
- arg=None,
- stack_before=[pydict, markobject, stackslice],
- stack_after=[pydict],
- proto=1,
- doc="""Add an arbitrary number of key+value pairs to an existing dict.
-
- The slice of the stack following the topmost markobject is taken as
- an alternating sequence of keys and values, added to the dict
- immediately under the topmost markobject. Everything at and after the
- topmost markobject is popped, leaving the mutated dict at the top
- of the stack.
-
- Stack before: ... pydict markobject key_1 value_1 ... key_n value_n
- Stack after: ... pydict
-
- where pydict has been modified via pydict[key_i] = value_i for i in
- 1, 2, ..., n, and in that order.
- """),
-
- # Ways to build sets
-
- I(name='EMPTY_SET',
- code='\x8f',
- arg=None,
- stack_before=[],
- stack_after=[pyset],
- proto=4,
- doc="Push an empty set."),
-
- I(name='ADDITEMS',
- code='\x90',
- arg=None,
- stack_before=[pyset, markobject, stackslice],
- stack_after=[pyset],
- proto=4,
- doc="""Add an arbitrary number of items to an existing set.
-
- The slice of the stack following the topmost markobject is taken as
- a sequence of items, added to the set immediately under the topmost
- markobject. Everything at and after the topmost markobject is popped,
- leaving the mutated set at the top of the stack.
-
- Stack before: ... pyset markobject item_1 ... item_n
- Stack after: ... pyset
-
- where pyset has been modified via pyset.add(item_i) = item_i for i in
- 1, 2, ..., n, and in that order.
- """),
-
- # Way to build frozensets
-
- I(name='FROZENSET',
- code='\x91',
- arg=None,
- stack_before=[markobject, stackslice],
- stack_after=[pyfrozenset],
- proto=4,
- doc="""Build a frozenset out of the topmost slice, after markobject.
-
- All the stack entries following the topmost markobject are placed into
- a single Python frozenset, which single frozenset object replaces all
- of the stack from the topmost markobject onward. For example,
-
- Stack before: ... markobject 1 2 3
- Stack after: ... frozenset({1, 2, 3})
- """),
-
- # Stack manipulation.
-
- I(name='POP',
- code='0',
- arg=None,
- stack_before=[anyobject],
- stack_after=[],
- proto=0,
- doc="Discard the top stack item, shrinking the stack by one item."),
-
- I(name='DUP',
- code='2',
- arg=None,
- stack_before=[anyobject],
- stack_after=[anyobject, anyobject],
- proto=0,
- doc="Push the top stack item onto the stack again, duplicating it."),
-
- I(name='MARK',
- code='(',
- arg=None,
- stack_before=[],
- stack_after=[markobject],
- proto=0,
- doc="""Push markobject onto the stack.
-
- markobject is a unique object, used by other opcodes to identify a
- region of the stack containing a variable number of objects for them
- to work on. See markobject.doc for more detail.
- """),
-
- I(name='POP_MARK',
- code='1',
- arg=None,
- stack_before=[markobject, stackslice],
- stack_after=[],
- proto=1,
- doc="""Pop all the stack objects at and above the topmost markobject.
-
- When an opcode using a variable number of stack objects is done,
- POP_MARK is used to remove those objects, and to remove the markobject
- that delimited their starting position on the stack.
- """),
-
- # Memo manipulation. There are really only two operations (get and put),
- # each in all-text, "short binary", and "long binary" flavors.
-
- I(name='GET',
- code='g',
- arg=decimalnl_short,
- stack_before=[],
- stack_after=[anyobject],
- proto=0,
- doc="""Read an object from the memo and push it on the stack.
-
- The index of the memo object to push is given by the newline-terminated
- decimal string following. BINGET and LONG_BINGET are space-optimized
- versions.
- """),
-
- I(name='BINGET',
- code='h',
- arg=uint1,
- stack_before=[],
- stack_after=[anyobject],
- proto=1,
- doc="""Read an object from the memo and push it on the stack.
-
- The index of the memo object to push is given by the 1-byte unsigned
- integer following.
- """),
-
- I(name='LONG_BINGET',
- code='j',
- arg=uint4,
- stack_before=[],
- stack_after=[anyobject],
- proto=1,
- doc="""Read an object from the memo and push it on the stack.
-
- The index of the memo object to push is given by the 4-byte unsigned
- little-endian integer following.
- """),
-
- I(name='PUT',
- code='p',
- arg=decimalnl_short,
- stack_before=[],
- stack_after=[],
- proto=0,
- doc="""Store the stack top into the memo. The stack is not popped.
-
- The index of the memo location to write into is given by the newline-
- terminated decimal string following. BINPUT and LONG_BINPUT are
- space-optimized versions.
- """),
-
- I(name='BINPUT',
- code='q',
- arg=uint1,
- stack_before=[],
- stack_after=[],
- proto=1,
- doc="""Store the stack top into the memo. The stack is not popped.
-
- The index of the memo location to write into is given by the 1-byte
- unsigned integer following.
- """),
-
- I(name='LONG_BINPUT',
- code='r',
- arg=uint4,
- stack_before=[],
- stack_after=[],
- proto=1,
- doc="""Store the stack top into the memo. The stack is not popped.
-
- The index of the memo location to write into is given by the 4-byte
- unsigned little-endian integer following.
- """),
-
- I(name='MEMOIZE',
- code='\x94',
- arg=None,
- stack_before=[anyobject],
- stack_after=[anyobject],
- proto=4,
- doc="""Store the stack top into the memo. The stack is not popped.
-
- The index of the memo location to write is the number of
- elements currently present in the memo.
- """),
-
- # Access the extension registry (predefined objects). Akin to the GET
- # family.
-
- I(name='EXT1',
- code='\x82',
- arg=uint1,
- stack_before=[],
- stack_after=[anyobject],
- proto=2,
- doc="""Extension code.
-
- This code and the similar EXT2 and EXT4 allow using a registry
- of popular objects that are pickled by name, typically classes.
- It is envisioned that through a global negotiation and
- registration process, third parties can set up a mapping between
- ints and object names.
-
- In order to guarantee pickle interchangeability, the extension
- code registry ought to be global, although a range of codes may
- be reserved for private use.
-
- EXT1 has a 1-byte integer argument. This is used to index into the
- extension registry, and the object at that index is pushed on the stack.
- """),
-
- I(name='EXT2',
- code='\x83',
- arg=uint2,
- stack_before=[],
- stack_after=[anyobject],
- proto=2,
- doc="""Extension code.
-
- See EXT1. EXT2 has a two-byte integer argument.
- """),
-
- I(name='EXT4',
- code='\x84',
- arg=int4,
- stack_before=[],
- stack_after=[anyobject],
- proto=2,
- doc="""Extension code.
-
- See EXT1. EXT4 has a four-byte integer argument.
- """),
-
- # Push a class object, or module function, on the stack, via its module
- # and name.
-
- I(name='GLOBAL',
- code='c',
- arg=stringnl_noescape_pair,
- stack_before=[],
- stack_after=[anyobject],
- proto=0,
- doc="""Push a global object (module.attr) on the stack.
-
- Two newline-terminated strings follow the GLOBAL opcode. The first is
- taken as a module name, and the second as a class name. The class
- object module.class is pushed on the stack. More accurately, the
- object returned by self.find_class(module, class) is pushed on the
- stack, so unpickling subclasses can override this form of lookup.
- """),
-
- I(name='STACK_GLOBAL',
- code='\x93',
- arg=None,
- stack_before=[pyunicode, pyunicode],
- stack_after=[anyobject],
- proto=4,
- doc="""Push a global object (module.attr) on the stack.
- """),
-
- # Ways to build objects of classes pickle doesn't know about directly
- # (user-defined classes). I despair of documenting this accurately
- # and comprehensibly -- you really have to read the pickle code to
- # find all the special cases.
-
- I(name='REDUCE',
- code='R',
- arg=None,
- stack_before=[anyobject, anyobject],
- stack_after=[anyobject],
- proto=0,
- doc="""Push an object built from a callable and an argument tuple.
-
- The opcode is named to remind of the __reduce__() method.
-
- Stack before: ... callable pytuple
- Stack after: ... callable(*pytuple)
-
- The callable and the argument tuple are the first two items returned
- by a __reduce__ method. Applying the callable to the argtuple is
- supposed to reproduce the original object, or at least get it started.
- If the __reduce__ method returns a 3-tuple, the last component is an
- argument to be passed to the object's __setstate__, and then the REDUCE
- opcode is followed by code to create setstate's argument, and then a
- BUILD opcode to apply __setstate__ to that argument.
-
- If not isinstance(callable, type), REDUCE complains unless the
- callable has been registered with the copyreg module's
- safe_constructors dict, or the callable has a magic
- '__safe_for_unpickling__' attribute with a true value. I'm not sure
- why it does this, but I've sure seen this complaint often enough when
- I didn't want to <wink>.
- """),
-
- I(name='BUILD',
- code='b',
- arg=None,
- stack_before=[anyobject, anyobject],
- stack_after=[anyobject],
- proto=0,
- doc="""Finish building an object, via __setstate__ or dict update.
-
- Stack before: ... anyobject argument
- Stack after: ... anyobject
-
- where anyobject may have been mutated, as follows:
-
- If the object has a __setstate__ method,
-
- anyobject.__setstate__(argument)
-
- is called.
-
- Else the argument must be a dict, the object must have a __dict__, and
- the object is updated via
-
- anyobject.__dict__.update(argument)
- """),
-
- I(name='INST',
- code='i',
- arg=stringnl_noescape_pair,
- stack_before=[markobject, stackslice],
- stack_after=[anyobject],
- proto=0,
- doc="""Build a class instance.
-
- This is the protocol 0 version of protocol 1's OBJ opcode.
- INST is followed by two newline-terminated strings, giving a
- module and class name, just as for the GLOBAL opcode (and see
- GLOBAL for more details about that). self.find_class(module, name)
- is used to get a class object.
-
- In addition, all the objects on the stack following the topmost
- markobject are gathered into a tuple and popped (along with the
- topmost markobject), just as for the TUPLE opcode.
-
- Now it gets complicated. If all of these are true:
-
- + The argtuple is empty (markobject was at the top of the stack
- at the start).
-
- + The class object does not have a __getinitargs__ attribute.
-
- then we want to create an old-style class instance without invoking
- its __init__() method (pickle has waffled on this over the years; not
- calling __init__() is current wisdom). In this case, an instance of
- an old-style dummy class is created, and then we try to rebind its
- __class__ attribute to the desired class object. If this succeeds,
- the new instance object is pushed on the stack, and we're done.
-
- Else (the argtuple is not empty, it's not an old-style class object,
- or the class object does have a __getinitargs__ attribute), the code
- first insists that the class object have a __safe_for_unpickling__
- attribute. Unlike as for the __safe_for_unpickling__ check in REDUCE,
- it doesn't matter whether this attribute has a true or false value, it
- only matters whether it exists (XXX this is a bug). If
- __safe_for_unpickling__ doesn't exist, UnpicklingError is raised.
-
- Else (the class object does have a __safe_for_unpickling__ attr),
- the class object obtained from INST's arguments is applied to the
- argtuple obtained from the stack, and the resulting instance object
- is pushed on the stack.
-
- NOTE: checks for __safe_for_unpickling__ went away in Python 2.3.
- NOTE: the distinction between old-style and new-style classes does
- not make sense in Python 3.
- """),
-
- I(name='OBJ',
- code='o',
- arg=None,
- stack_before=[markobject, anyobject, stackslice],
- stack_after=[anyobject],
- proto=1,
- doc="""Build a class instance.
-
- This is the protocol 1 version of protocol 0's INST opcode, and is
- very much like it. The major difference is that the class object
- is taken off the stack, allowing it to be retrieved from the memo
- repeatedly if several instances of the same class are created. This
- can be much more efficient (in both time and space) than repeatedly
- embedding the module and class names in INST opcodes.
-
- Unlike INST, OBJ takes no arguments from the opcode stream. Instead
- the class object is taken off the stack, immediately above the
- topmost markobject:
-
- Stack before: ... markobject classobject stackslice
- Stack after: ... new_instance_object
-
- As for INST, the remainder of the stack above the markobject is
- gathered into an argument tuple, and then the logic seems identical,
- except that no __safe_for_unpickling__ check is done (XXX this is
- a bug). See INST for the gory details.
-
- NOTE: In Python 2.3, INST and OBJ are identical except for how they
- get the class object. That was always the intent; the implementations
- had diverged for accidental reasons.
- """),
-
- I(name='NEWOBJ',
- code='\x81',
- arg=None,
- stack_before=[anyobject, anyobject],
- stack_after=[anyobject],
- proto=2,
- doc="""Build an object instance.
-
- The stack before should be thought of as containing a class
- object followed by an argument tuple (the tuple being the stack
- top). Call these cls and args. They are popped off the stack,
- and the value returned by cls.__new__(cls, *args) is pushed back
- onto the stack.
- """),
-
- I(name='NEWOBJ_EX',
- code='\x92',
- arg=None,
- stack_before=[anyobject, anyobject, anyobject],
- stack_after=[anyobject],
- proto=4,
- doc="""Build an object instance.
-
- The stack before should be thought of as containing a class
- object followed by an argument tuple and by a keyword argument dict
- (the dict being the stack top). Call these cls and args. They are
- popped off the stack, and the value returned by
- cls.__new__(cls, *args, *kwargs) is pushed back onto the stack.
- """),
-
- # Machine control.
-
- I(name='PROTO',
- code='\x80',
- arg=uint1,
- stack_before=[],
- stack_after=[],
- proto=2,
- doc="""Protocol version indicator.
-
- For protocol 2 and above, a pickle must start with this opcode.
- The argument is the protocol version, an int in range(2, 256).
- """),
-
- I(name='STOP',
- code='.',
- arg=None,
- stack_before=[anyobject],
- stack_after=[],
- proto=0,
- doc="""Stop the unpickling machine.
-
- Every pickle ends with this opcode. The object at the top of the stack
- is popped, and that's the result of unpickling. The stack should be
- empty then.
- """),
-
- # Framing support.
-
- I(name='FRAME',
- code='\x95',
- arg=uint8,
- stack_before=[],
- stack_after=[],
- proto=4,
- doc="""Indicate the beginning of a new frame.
-
- The unpickler may use this opcode to safely prefetch data from its
- underlying stream.
- """),
-
- # Ways to deal with persistent IDs.
-
- I(name='PERSID',
- code='P',
- arg=stringnl_noescape,
- stack_before=[],
- stack_after=[anyobject],
- proto=0,
- doc="""Push an object identified by a persistent ID.
-
- The pickle module doesn't define what a persistent ID means. PERSID's
- argument is a newline-terminated str-style (no embedded escapes, no
- bracketing quote characters) string, which *is* "the persistent ID".
- The unpickler passes this string to self.persistent_load(). Whatever
- object that returns is pushed on the stack. There is no implementation
- of persistent_load() in Python's unpickler: it must be supplied by an
- unpickler subclass.
- """),
-
- I(name='BINPERSID',
- code='Q',
- arg=None,
- stack_before=[anyobject],
- stack_after=[anyobject],
- proto=1,
- doc="""Push an object identified by a persistent ID.
-
- Like PERSID, except the persistent ID is popped off the stack (instead
- of being a string embedded in the opcode bytestream). The persistent
- ID is passed to self.persistent_load(), and whatever object that
- returns is pushed on the stack. See PERSID for more detail.
- """),
-]
-del I
-
-# Verify uniqueness of .name and .code members.
-name2i = {}
-code2i = {}
-
-for i, d in enumerate(opcodes):
- if d.name in name2i:
- raise ValueError("repeated name %r at indices %d and %d" %
- (d.name, name2i[d.name], i))
- if d.code in code2i:
- raise ValueError("repeated code %r at indices %d and %d" %
- (d.code, code2i[d.code], i))
-
- name2i[d.name] = i
- code2i[d.code] = i
-
-del name2i, code2i, i, d
-
-##############################################################################
-# Build a code2op dict, mapping opcode characters to OpcodeInfo records.
-# Also ensure we've got the same stuff as pickle.py, although the
-# introspection here is dicey.
-
-code2op = {}
-for d in opcodes:
- code2op[d.code] = d
-del d
-
-def assure_pickle_consistency(verbose=False):
-
- copy = code2op.copy()
- for name in pickle.__all__:
- if not re.match("[A-Z][A-Z0-9_]+$", name):
- if verbose:
- print("skipping %r: it doesn't look like an opcode name" % name)
- continue
- picklecode = getattr(pickle, name)
- if not isinstance(picklecode, bytes) or len(picklecode) != 1:
- if verbose:
- print(("skipping %r: value %r doesn't look like a pickle "
- "code" % (name, picklecode)))
- continue
- picklecode = picklecode.decode("latin-1")
- if picklecode in copy:
- if verbose:
- print("checking name %r w/ code %r for consistency" % (
- name, picklecode))
- d = copy[picklecode]
- if d.name != name:
- raise ValueError("for pickle code %r, pickle.py uses name %r "
- "but we're using name %r" % (picklecode,
- name,
- d.name))
- # Forget this one. Any left over in copy at the end are a problem
- # of a different kind.
- del copy[picklecode]
- else:
- raise ValueError("pickle.py appears to have a pickle opcode with "
- "name %r and code %r, but we don't" %
- (name, picklecode))
- if copy:
- msg = ["we appear to have pickle opcodes that pickle.py doesn't have:"]
- for code, d in copy.items():
- msg.append(" name %r with code %r" % (d.name, code))
- raise ValueError("\n".join(msg))
-
-assure_pickle_consistency()
-del assure_pickle_consistency
-
-##############################################################################
-# A pickle opcode generator.
-
-def _genops(data, yield_end_pos=False):
- if isinstance(data, bytes_types):
- data = io.BytesIO(data)
-
- if hasattr(data, "tell"):
- getpos = data.tell
- else:
- getpos = lambda: None
-
- while True:
- pos = getpos()
- code = data.read(1)
- opcode = code2op.get(code.decode("latin-1"))
- if opcode is None:
- if code == b"":
- raise ValueError("pickle exhausted before seeing STOP")
- else:
- raise ValueError("at position %s, opcode %r unknown" % (
- "<unknown>" if pos is None else pos,
- code))
- if opcode.arg is None:
- arg = None
- else:
- arg = opcode.arg.reader(data)
- if yield_end_pos:
- yield opcode, arg, pos, getpos()
- else:
- yield opcode, arg, pos
- if code == b'.':
- assert opcode.name == 'STOP'
- break
-
-def genops(pickle):
- """Generate all the opcodes in a pickle.
-
- 'pickle' is a file-like object, or string, containing the pickle.
-
- Each opcode in the pickle is generated, from the current pickle position,
- stopping after a STOP opcode is delivered. A triple is generated for
- each opcode:
-
- opcode, arg, pos
-
- opcode is an OpcodeInfo record, describing the current opcode.
-
- If the opcode has an argument embedded in the pickle, arg is its decoded
- value, as a Python object. If the opcode doesn't have an argument, arg
- is None.
-
- If the pickle has a tell() method, pos was the value of pickle.tell()
- before reading the current opcode. If the pickle is a bytes object,
- it's wrapped in a BytesIO object, and the latter's tell() result is
- used. Else (the pickle doesn't have a tell(), and it's not obvious how
- to query its current position) pos is None.
- """
- return _genops(pickle)
-
-##############################################################################
-# A pickle optimizer.
-
-def optimize(p):
- 'Optimize a pickle string by removing unused PUT opcodes'
- put = 'PUT'
- get = 'GET'
- oldids = set() # set of all PUT ids
- newids = {} # set of ids used by a GET opcode
- opcodes = [] # (op, idx) or (pos, end_pos)
- proto = 0
- protoheader = b''
- for opcode, arg, pos, end_pos in _genops(p, yield_end_pos=True):
- if 'PUT' in opcode.name:
- oldids.add(arg)
- opcodes.append((put, arg))
- elif opcode.name == 'MEMOIZE':
- idx = len(oldids)
- oldids.add(idx)
- opcodes.append((put, idx))
- elif 'FRAME' in opcode.name:
- pass
- elif 'GET' in opcode.name:
- if opcode.proto > proto:
- proto = opcode.proto
- newids[arg] = None
- opcodes.append((get, arg))
- elif opcode.name == 'PROTO':
- if arg > proto:
- proto = arg
- if pos == 0:
- protoheader = p[pos:end_pos]
- else:
- opcodes.append((pos, end_pos))
- else:
- opcodes.append((pos, end_pos))
- del oldids
-
- # Copy the opcodes except for PUTS without a corresponding GET
- out = io.BytesIO()
- # Write the PROTO header before any framing
- out.write(protoheader)
- pickler = pickle._Pickler(out, proto)
- if proto >= 4:
- pickler.framer.start_framing()
- idx = 0
- for op, arg in opcodes:
- frameless = False
- if op is put:
- if arg not in newids:
- continue
- data = pickler.put(idx)
- newids[arg] = idx
- idx += 1
- elif op is get:
- data = pickler.get(newids[arg])
- else:
- data = p[op:arg]
- frameless = len(data) > pickler.framer._FRAME_SIZE_TARGET
- pickler.framer.commit_frame(force=frameless)
- if frameless:
- pickler.framer.file_write(data)
- else:
- pickler.write(data)
- pickler.framer.end_framing()
- return out.getvalue()
-
-##############################################################################
-# A symbolic pickle disassembler.
-
-def dis(pickle, out=None, memo=None, indentlevel=4, annotate=0):
- """Produce a symbolic disassembly of a pickle.
-
- 'pickle' is a file-like object, or string, containing a (at least one)
- pickle. The pickle is disassembled from the current position, through
- the first STOP opcode encountered.
-
- Optional arg 'out' is a file-like object to which the disassembly is
- printed. It defaults to sys.stdout.
-
- Optional arg 'memo' is a Python dict, used as the pickle's memo. It
- may be mutated by dis(), if the pickle contains PUT or BINPUT opcodes.
- Passing the same memo object to another dis() call then allows disassembly
- to proceed across multiple pickles that were all created by the same
- pickler with the same memo. Ordinarily you don't need to worry about this.
-
- Optional arg 'indentlevel' is the number of blanks by which to indent
- a new MARK level. It defaults to 4.
-
- Optional arg 'annotate' if nonzero instructs dis() to add short
- description of the opcode on each line of disassembled output.
- The value given to 'annotate' must be an integer and is used as a
- hint for the column where annotation should start. The default
- value is 0, meaning no annotations.
-
- In addition to printing the disassembly, some sanity checks are made:
-
- + All embedded opcode arguments "make sense".
-
- + Explicit and implicit pop operations have enough items on the stack.
-
- + When an opcode implicitly refers to a markobject, a markobject is
- actually on the stack.
-
- + A memo entry isn't referenced before it's defined.
-
- + The markobject isn't stored in the memo.
-
- + A memo entry isn't redefined.
- """
-
- # Most of the hair here is for sanity checks, but most of it is needed
- # anyway to detect when a protocol 0 POP takes a MARK off the stack
- # (which in turn is needed to indent MARK blocks correctly).
-
- stack = [] # crude emulation of unpickler stack
- if memo is None:
- memo = {} # crude emulation of unpickler memo
- maxproto = -1 # max protocol number seen
- markstack = [] # bytecode positions of MARK opcodes
- indentchunk = ' ' * indentlevel
- errormsg = None
- annocol = annotate # column hint for annotations
- for opcode, arg, pos in genops(pickle):
- if pos is not None:
- print("%5d:" % pos, end=' ', file=out)
-
- line = "%-4s %s%s" % (repr(opcode.code)[1:-1],
- indentchunk * len(markstack),
- opcode.name)
-
- maxproto = max(maxproto, opcode.proto)
- before = opcode.stack_before # don't mutate
- after = opcode.stack_after # don't mutate
- numtopop = len(before)
-
- # See whether a MARK should be popped.
- markmsg = None
- if markobject in before or (opcode.name == "POP" and
- stack and
- stack[-1] is markobject):
- assert markobject not in after
- if __debug__:
- if markobject in before:
- assert before[-1] is stackslice
- if markstack:
- markpos = markstack.pop()
- if markpos is None:
- markmsg = "(MARK at unknown opcode offset)"
- else:
- markmsg = "(MARK at %d)" % markpos
- # Pop everything at and after the topmost markobject.
- while stack[-1] is not markobject:
- stack.pop()
- stack.pop()
- # Stop later code from popping too much.
- try:
- numtopop = before.index(markobject)
- except ValueError:
- assert opcode.name == "POP"
- numtopop = 0
- else:
- errormsg = markmsg = "no MARK exists on stack"
-
- # Check for correct memo usage.
- if opcode.name in ("PUT", "BINPUT", "LONG_BINPUT", "MEMOIZE"):
- if opcode.name == "MEMOIZE":
- memo_idx = len(memo)
- markmsg = "(as %d)" % memo_idx
- else:
- assert arg is not None
- memo_idx = arg
- if memo_idx in memo:
- errormsg = "memo key %r already defined" % arg
- elif not stack:
- errormsg = "stack is empty -- can't store into memo"
- elif stack[-1] is markobject:
- errormsg = "can't store markobject in the memo"
- else:
- memo[memo_idx] = stack[-1]
- elif opcode.name in ("GET", "BINGET", "LONG_BINGET"):
- if arg in memo:
- assert len(after) == 1
- after = [memo[arg]] # for better stack emulation
- else:
- errormsg = "memo key %r has never been stored into" % arg
-
- if arg is not None or markmsg:
- # make a mild effort to align arguments
- line += ' ' * (10 - len(opcode.name))
- if arg is not None:
- line += ' ' + repr(arg)
- if markmsg:
- line += ' ' + markmsg
- if annotate:
- line += ' ' * (annocol - len(line))
- # make a mild effort to align annotations
- annocol = len(line)
- if annocol > 50:
- annocol = annotate
- line += ' ' + opcode.doc.split('\n', 1)[0]
- print(line, file=out)
-
- if errormsg:
- # Note that we delayed complaining until the offending opcode
- # was printed.
- raise ValueError(errormsg)
-
- # Emulate the stack effects.
- if len(stack) < numtopop:
- raise ValueError("tries to pop %d items from stack with "
- "only %d items" % (numtopop, len(stack)))
- if numtopop:
- del stack[-numtopop:]
- if markobject in after:
- assert markobject not in before
- markstack.append(pos)
-
- stack.extend(after)
-
- print("highest protocol among opcodes =", maxproto, file=out)
- if stack:
- raise ValueError("stack not empty after STOP: %r" % stack)
-
-# For use in the doctest, simply as an example of a class to pickle.
-class _Example:
- def __init__(self, value):
- self.value = value
-
-_dis_test = r"""
->>> import pickle
->>> x = [1, 2, (3, 4), {b'abc': "def"}]
->>> pkl0 = pickle.dumps(x, 0)
->>> dis(pkl0)
- 0: ( MARK
- 1: l LIST (MARK at 0)
- 2: p PUT 0
- 5: I INT 1
- 8: a APPEND
- 9: I INT 2
- 12: a APPEND
- 13: ( MARK
- 14: I INT 3
- 17: I INT 4
- 20: t TUPLE (MARK at 13)
- 21: p PUT 1
- 24: a APPEND
- 25: ( MARK
- 26: d DICT (MARK at 25)
- 27: p PUT 2
- 30: c GLOBAL '_codecs encode'
- 46: p PUT 3
- 49: ( MARK
- 50: V UNICODE 'abc'
- 55: p PUT 4
- 58: V UNICODE 'latin1'
- 66: p PUT 5
- 69: t TUPLE (MARK at 49)
- 70: p PUT 6
- 73: R REDUCE
- 74: p PUT 7
- 77: V UNICODE 'def'
- 82: p PUT 8
- 85: s SETITEM
- 86: a APPEND
- 87: . STOP
-highest protocol among opcodes = 0
-
-Try again with a "binary" pickle.
-
->>> pkl1 = pickle.dumps(x, 1)
->>> dis(pkl1)
- 0: ] EMPTY_LIST
- 1: q BINPUT 0
- 3: ( MARK
- 4: K BININT1 1
- 6: K BININT1 2
- 8: ( MARK
- 9: K BININT1 3
- 11: K BININT1 4
- 13: t TUPLE (MARK at 8)
- 14: q BINPUT 1
- 16: } EMPTY_DICT
- 17: q BINPUT 2
- 19: c GLOBAL '_codecs encode'
- 35: q BINPUT 3
- 37: ( MARK
- 38: X BINUNICODE 'abc'
- 46: q BINPUT 4
- 48: X BINUNICODE 'latin1'
- 59: q BINPUT 5
- 61: t TUPLE (MARK at 37)
- 62: q BINPUT 6
- 64: R REDUCE
- 65: q BINPUT 7
- 67: X BINUNICODE 'def'
- 75: q BINPUT 8
- 77: s SETITEM
- 78: e APPENDS (MARK at 3)
- 79: . STOP
-highest protocol among opcodes = 1
-
-Exercise the INST/OBJ/BUILD family.
-
->>> import pickletools
->>> dis(pickle.dumps(pickletools.dis, 0))
- 0: c GLOBAL 'pickletools dis'
- 17: p PUT 0
- 20: . STOP
-highest protocol among opcodes = 0
-
->>> from pickletools import _Example
->>> x = [_Example(42)] * 2
->>> dis(pickle.dumps(x, 0))
- 0: ( MARK
- 1: l LIST (MARK at 0)
- 2: p PUT 0
- 5: c GLOBAL 'copy_reg _reconstructor'
- 30: p PUT 1
- 33: ( MARK
- 34: c GLOBAL 'pickletools _Example'
- 56: p PUT 2
- 59: c GLOBAL '__builtin__ object'
- 79: p PUT 3
- 82: N NONE
- 83: t TUPLE (MARK at 33)
- 84: p PUT 4
- 87: R REDUCE
- 88: p PUT 5
- 91: ( MARK
- 92: d DICT (MARK at 91)
- 93: p PUT 6
- 96: V UNICODE 'value'
- 103: p PUT 7
- 106: I INT 42
- 110: s SETITEM
- 111: b BUILD
- 112: a APPEND
- 113: g GET 5
- 116: a APPEND
- 117: . STOP
-highest protocol among opcodes = 0
-
->>> dis(pickle.dumps(x, 1))
- 0: ] EMPTY_LIST
- 1: q BINPUT 0
- 3: ( MARK
- 4: c GLOBAL 'copy_reg _reconstructor'
- 29: q BINPUT 1
- 31: ( MARK
- 32: c GLOBAL 'pickletools _Example'
- 54: q BINPUT 2
- 56: c GLOBAL '__builtin__ object'
- 76: q BINPUT 3
- 78: N NONE
- 79: t TUPLE (MARK at 31)
- 80: q BINPUT 4
- 82: R REDUCE
- 83: q BINPUT 5
- 85: } EMPTY_DICT
- 86: q BINPUT 6
- 88: X BINUNICODE 'value'
- 98: q BINPUT 7
- 100: K BININT1 42
- 102: s SETITEM
- 103: b BUILD
- 104: h BINGET 5
- 106: e APPENDS (MARK at 3)
- 107: . STOP
-highest protocol among opcodes = 1
-
-Try "the canonical" recursive-object test.
-
->>> L = []
->>> T = L,
->>> L.append(T)
->>> L[0] is T
-True
->>> T[0] is L
-True
->>> L[0][0] is L
-True
->>> T[0][0] is T
-True
->>> dis(pickle.dumps(L, 0))
- 0: ( MARK
- 1: l LIST (MARK at 0)
- 2: p PUT 0
- 5: ( MARK
- 6: g GET 0
- 9: t TUPLE (MARK at 5)
- 10: p PUT 1
- 13: a APPEND
- 14: . STOP
-highest protocol among opcodes = 0
-
->>> dis(pickle.dumps(L, 1))
- 0: ] EMPTY_LIST
- 1: q BINPUT 0
- 3: ( MARK
- 4: h BINGET 0
- 6: t TUPLE (MARK at 3)
- 7: q BINPUT 1
- 9: a APPEND
- 10: . STOP
-highest protocol among opcodes = 1
-
-Note that, in the protocol 0 pickle of the recursive tuple, the disassembler
-has to emulate the stack in order to realize that the POP opcode at 16 gets
-rid of the MARK at 0.
-
->>> dis(pickle.dumps(T, 0))
- 0: ( MARK
- 1: ( MARK
- 2: l LIST (MARK at 1)
- 3: p PUT 0
- 6: ( MARK
- 7: g GET 0
- 10: t TUPLE (MARK at 6)
- 11: p PUT 1
- 14: a APPEND
- 15: 0 POP
- 16: 0 POP (MARK at 0)
- 17: g GET 1
- 20: . STOP
-highest protocol among opcodes = 0
-
->>> dis(pickle.dumps(T, 1))
- 0: ( MARK
- 1: ] EMPTY_LIST
- 2: q BINPUT 0
- 4: ( MARK
- 5: h BINGET 0
- 7: t TUPLE (MARK at 4)
- 8: q BINPUT 1
- 10: a APPEND
- 11: 1 POP_MARK (MARK at 0)
- 12: h BINGET 1
- 14: . STOP
-highest protocol among opcodes = 1
-
-Try protocol 2.
-
->>> dis(pickle.dumps(L, 2))
- 0: \x80 PROTO 2
- 2: ] EMPTY_LIST
- 3: q BINPUT 0
- 5: h BINGET 0
- 7: \x85 TUPLE1
- 8: q BINPUT 1
- 10: a APPEND
- 11: . STOP
-highest protocol among opcodes = 2
-
->>> dis(pickle.dumps(T, 2))
- 0: \x80 PROTO 2
- 2: ] EMPTY_LIST
- 3: q BINPUT 0
- 5: h BINGET 0
- 7: \x85 TUPLE1
- 8: q BINPUT 1
- 10: a APPEND
- 11: 0 POP
- 12: h BINGET 1
- 14: . STOP
-highest protocol among opcodes = 2
-
-Try protocol 3 with annotations:
-
->>> dis(pickle.dumps(T, 3), annotate=1)
- 0: \x80 PROTO 3 Protocol version indicator.
- 2: ] EMPTY_LIST Push an empty list.
- 3: q BINPUT 0 Store the stack top into the memo. The stack is not popped.
- 5: h BINGET 0 Read an object from the memo and push it on the stack.
- 7: \x85 TUPLE1 Build a one-tuple out of the topmost item on the stack.
- 8: q BINPUT 1 Store the stack top into the memo. The stack is not popped.
- 10: a APPEND Append an object to a list.
- 11: 0 POP Discard the top stack item, shrinking the stack by one item.
- 12: h BINGET 1 Read an object from the memo and push it on the stack.
- 14: . STOP Stop the unpickling machine.
-highest protocol among opcodes = 2
-
-"""
-
-_memo_test = r"""
->>> import pickle
->>> import io
->>> f = io.BytesIO()
->>> p = pickle.Pickler(f, 2)
->>> x = [1, 2, 3]
->>> p.dump(x)
->>> p.dump(x)
->>> f.seek(0)
-0
->>> memo = {}
->>> dis(f, memo=memo)
- 0: \x80 PROTO 2
- 2: ] EMPTY_LIST
- 3: q BINPUT 0
- 5: ( MARK
- 6: K BININT1 1
- 8: K BININT1 2
- 10: K BININT1 3
- 12: e APPENDS (MARK at 5)
- 13: . STOP
-highest protocol among opcodes = 2
->>> dis(f, memo=memo)
- 14: \x80 PROTO 2
- 16: h BINGET 0
- 18: . STOP
-highest protocol among opcodes = 2
-"""
-
-__test__ = {'disassembler_test': _dis_test,
- 'disassembler_memo_test': _memo_test,
- }
-
-def _test():
- import doctest
- return doctest.testmod()
-
-if __name__ == "__main__":
- import argparse
- parser = argparse.ArgumentParser(
- description='disassemble one or more pickle files')
- parser.add_argument(
- 'pickle_file', type=argparse.FileType('br'),
- nargs='*', help='the pickle file')
- parser.add_argument(
- '-o', '--output', default=sys.stdout, type=argparse.FileType('w'),
- help='the file where the output should be written')
- parser.add_argument(
- '-m', '--memo', action='store_true',
- help='preserve memo between disassemblies')
- parser.add_argument(
- '-l', '--indentlevel', default=4, type=int,
- help='the number of blanks by which to indent a new MARK level')
- parser.add_argument(
- '-a', '--annotate', action='store_true',
- help='annotate each line with a short opcode description')
- parser.add_argument(
- '-p', '--preamble', default="==> {name} <==",
- help='if more than one pickle file is specified, print this before'
- ' each disassembly')
- parser.add_argument(
- '-t', '--test', action='store_true',
- help='run self-test suite')
- parser.add_argument(
- '-v', action='store_true',
- help='run verbosely; only affects self-test run')
- args = parser.parse_args()
- if args.test:
- _test()
- else:
- annotate = 30 if args.annotate else 0
- if not args.pickle_file:
- parser.print_help()
- elif len(args.pickle_file) == 1:
- dis(args.pickle_file[0], args.output, None,
- args.indentlevel, annotate)
- else:
- memo = {} if args.memo else None
- for f in args.pickle_file:
- preamble = args.preamble.format(name=f.name)
- args.output.write(preamble + '\n')
- dis(f, args.output, memo, args.indentlevel, annotate)