python-uncompyle6/uncompyle6/disas.py
rocky 34ecd54e2c README.rst: note addition of pydisassemble
Remove duplicate disassembly printing from scanners and
put common code in caller(s). Show source-code line numbers in disassembly output
and fix alignment of byte offsets.
disas.py: workaround Python 2/3 different layouts before we get to
bytecodes in a code object.
2015-12-15 01:42:07 -05:00

202 lines
6.5 KiB
Python

from __future__ import print_function
"""Disassembler of Python byte code into mnemonics.
This is needed when the bytecode extracted is from
a different version than the currently-running Python.
When the two are the same, you can simply use marshal.loads()
to prodoce a code object
"""
import imp, marshal, pickle, sys, types
import dis as Mdis
from struct import unpack
import uncompyle6
from uncompyle6.magics import magic2int
internStrings = []
# XXX For backwards compatibility
disco = Mdis.disassemble
PYTHON3 = (sys.version_info >= (3, 0))
PYTHON_MAGIC_INT = magic2int(imp.get_magic())
if PYTHON3:
def long(n): return n
def compat_str(s):
return s.decode('utf-8', errors='ignore') if PYTHON3 else str(s)
def marshalLoad(fp):
global internStrings
internStrings = []
return load(fp)
def load(fp, magic_int):
"""
marshal.load() written in Python. When the Python bytecode magic loaded is the
same magic for the running Python interpreter, we can simply use the
Python-supplied mashal.load().
However we need to use this when versions are different since the internal
code structures are different. Sigh.
"""
global internStrings
marshalType = fp.read(1).decode('utf-8')
if marshalType == 'c':
Code = types.CodeType
# FIXME If 'i' is deprecated, what would we use?
co_argcount = unpack('i', fp.read(4))[0]
co_nlocals = unpack('i', fp.read(4))[0]
co_stacksize = unpack('i', fp.read(4))[0]
co_flags = unpack('i', fp.read(4))[0]
# FIXME: somewhere between Python 2.7 and python 3.2 there's
# another 4 bytes before we get to the bytecode. What's going on?
# Again, because magic ints decreased between python 2.7 and 3.0 we need
# a range here.
if 3000 < magic_int < 20121:
fp.read(4)
co_code = load(fp, magic_int)
co_consts = load(fp, magic_int)
co_names = load(fp, magic_int)
co_varnames = load(fp, magic_int)
co_freevars = load(fp, magic_int)
co_cellvars = load(fp, magic_int)
co_filename = load(fp, magic_int)
co_name = load(fp, magic_int)
co_firstlineno = unpack('i', fp.read(4))[0]
co_lnotab = load(fp, magic_int)
# The Python3 code object is different than Python2's which
# we are reading if we get here.
# Also various parameters which were strings are now
# bytes (which is probably more logical).
if PYTHON3:
if PYTHON_MAGIC_INT > 3020:
# In later Python3 magic_ints, there is a
# kwonlyargcount parameter which we set to 0.
return Code(co_argcount, 0, co_nlocals, co_stacksize, co_flags,
bytes(co_code, encoding='utf-8'),
co_consts, co_names, co_varnames, co_filename, co_name,
co_firstlineno, bytes(co_lnotab, encoding='utf-8'),
co_freevars, co_cellvars)
else:
return Code(co_argcount, 0, co_nlocals, co_stacksize, co_flags,
bytes(co_code, encoding='utf-8'),
co_consts, co_names, co_varnames, co_filename, co_name,
co_firstlineno, bytes(co_lnotab, encoding='utf-8'),
co_freevars, co_cellvars)
else:
return Code(co_argcount, co_nlocals, co_stacksize, co_flags, co_code,
co_consts, co_names, co_varnames, co_filename, co_name,
co_firstlineno, co_lnotab, co_freevars, co_cellvars)
# const type
elif marshalType == '.':
return Ellipsis
elif marshalType == '0':
raise KeyError(marshalType)
return None
elif marshalType == 'N':
return None
elif marshalType == 'T':
return True
elif marshalType == 'F':
return False
elif marshalType == 'S':
return StopIteration
# number type
elif marshalType == 'f':
n = fp.read(1)
return float(unpack('d', fp.read(n))[0])
elif marshalType == 'g':
return float(unpack('d', fp.read(8))[0])
elif marshalType == 'i':
return int(unpack('i', fp.read(4))[0])
elif marshalType == 'I':
return unpack('q', fp.read(8))[0]
elif marshalType == 'x':
raise KeyError(marshalType)
return None
elif marshalType == 'y':
raise KeyError(marshalType)
return None
elif marshalType == 'l':
n = unpack('i', fp.read(4))[0]
if n == 0:
return long(0)
size = abs(n)
d = long(0)
for j in range(0, size):
md = int(unpack('h', fp.read(2))[0])
d += md << j*15
if n < 0:
return long(d*-1)
return d
# strings type
elif marshalType == 'R':
refnum = unpack('i', fp.read(4))[0]
return internStrings[refnum]
elif marshalType == 's':
strsize = unpack('i', fp.read(4))[0]
return compat_str(fp.read(strsize))
elif marshalType == 't':
strsize = unpack('i', fp.read(4))[0]
interned = compat_str(fp.read(strsize))
internStrings.append(interned)
return interned
elif marshalType == 'u':
strsize = unpack('i', fp.read(4))[0]
unicodestring = fp.read(strsize)
return unicodestring.decode('utf-8')
# collection type
elif marshalType == '(':
tuplesize = unpack('i', fp.read(4))[0]
ret = tuple()
while tuplesize > 0:
ret += load(fp, magic_int),
tuplesize -= 1
return ret
elif marshalType == '[':
raise KeyError(marshalType)
return None
elif marshalType == '{':
raise KeyError(marshalType)
return None
elif marshalType in ['<', '>']:
raise KeyError(marshalType)
return None
else:
sys.stderr.write("Unknown type %i (hex %x)\n" % (ord(marshalType), ord(marshalType)))
def _test():
"""Simple test program to disassemble a file."""
if sys.argv[1:]:
if sys.argv[2:]:
sys.stderr.write("usage: python dis.py [-|file]\n")
sys.exit(2)
fn = sys.argv[1]
if not fn or fn == "-":
fn = None
else:
fn = None
if fn is None:
f = sys.stdin
else:
f = open(fn)
source = f.read()
if fn is not None:
f.close()
else:
fn = "<stdin>"
code = compile(source, fn, "exec")
Mdis.dis(code)
if __name__ == "__main__":
_test()