mirror of https://github.com/python/cpython
312 lines
9.6 KiB
Python
312 lines
9.6 KiB
Python
"""Disassembler of Python byte code into mnemonics."""
|
|
|
|
import sys
|
|
import types
|
|
|
|
from opcode import *
|
|
from opcode import __all__ as _opcodes_all
|
|
|
|
__all__ = ["dis", "disassemble", "distb", "disco",
|
|
"findlinestarts", "findlabels"] + _opcodes_all
|
|
del _opcodes_all
|
|
|
|
_have_code = (types.MethodType, types.FunctionType, types.CodeType, type)
|
|
|
|
def _try_compile(source, name):
|
|
"""Attempts to compile the given source, first as an expression and
|
|
then as a statement if the first approach fails.
|
|
|
|
Utility function to accept strings in functions that otherwise
|
|
expect code objects
|
|
"""
|
|
try:
|
|
c = compile(source, name, 'eval')
|
|
except SyntaxError:
|
|
c = compile(source, name, 'exec')
|
|
return c
|
|
|
|
def dis(x=None):
|
|
"""Disassemble classes, methods, functions, or code.
|
|
|
|
With no argument, disassemble the last traceback.
|
|
|
|
"""
|
|
if x is None:
|
|
distb()
|
|
return
|
|
if hasattr(x, '__func__'): # Method
|
|
x = x.__func__
|
|
if hasattr(x, '__code__'): # Function
|
|
x = x.__code__
|
|
if hasattr(x, '__dict__'): # Class or module
|
|
items = sorted(x.__dict__.items())
|
|
for name, x1 in items:
|
|
if isinstance(x1, _have_code):
|
|
print("Disassembly of %s:" % name)
|
|
try:
|
|
dis(x1)
|
|
except TypeError as msg:
|
|
print("Sorry:", msg)
|
|
print()
|
|
elif hasattr(x, 'co_code'): # Code object
|
|
disassemble(x)
|
|
elif isinstance(x, (bytes, bytearray)): # Raw bytecode
|
|
_disassemble_bytes(x)
|
|
elif isinstance(x, str): # Source code
|
|
_disassemble_str(x)
|
|
else:
|
|
raise TypeError("don't know how to disassemble %s objects" %
|
|
type(x).__name__)
|
|
|
|
def distb(tb=None):
|
|
"""Disassemble a traceback (default: last traceback)."""
|
|
if tb is None:
|
|
try:
|
|
tb = sys.last_traceback
|
|
except AttributeError:
|
|
raise RuntimeError("no last traceback to disassemble")
|
|
while tb.tb_next: tb = tb.tb_next
|
|
disassemble(tb.tb_frame.f_code, tb.tb_lasti)
|
|
|
|
# The inspect module interrogates this dictionary to build its
|
|
# list of CO_* constants. It is also used by pretty_flags to
|
|
# turn the co_flags field into a human readable list.
|
|
COMPILER_FLAG_NAMES = {
|
|
1: "OPTIMIZED",
|
|
2: "NEWLOCALS",
|
|
4: "VARARGS",
|
|
8: "VARKEYWORDS",
|
|
16: "NESTED",
|
|
32: "GENERATOR",
|
|
64: "NOFREE",
|
|
}
|
|
|
|
def pretty_flags(flags):
|
|
"""Return pretty representation of code flags."""
|
|
names = []
|
|
for i in range(32):
|
|
flag = 1<<i
|
|
if flags & flag:
|
|
names.append(COMPILER_FLAG_NAMES.get(flag, hex(flag)))
|
|
flags ^= flag
|
|
if not flags:
|
|
break
|
|
else:
|
|
names.append(hex(flags))
|
|
return ", ".join(names)
|
|
|
|
def code_info(x):
|
|
"""Formatted details of methods, functions, or code."""
|
|
if hasattr(x, '__func__'): # Method
|
|
x = x.__func__
|
|
if hasattr(x, '__code__'): # Function
|
|
x = x.__code__
|
|
if isinstance(x, str): # Source code
|
|
x = _try_compile(x, "<code_info>")
|
|
if hasattr(x, 'co_code'): # Code object
|
|
return _format_code_info(x)
|
|
else:
|
|
raise TypeError("don't know how to disassemble %s objects" %
|
|
type(x).__name__)
|
|
|
|
def _format_code_info(co):
|
|
lines = []
|
|
lines.append("Name: %s" % co.co_name)
|
|
lines.append("Filename: %s" % co.co_filename)
|
|
lines.append("Argument count: %s" % co.co_argcount)
|
|
lines.append("Kw-only arguments: %s" % co.co_kwonlyargcount)
|
|
lines.append("Number of locals: %s" % co.co_nlocals)
|
|
lines.append("Stack size: %s" % co.co_stacksize)
|
|
lines.append("Flags: %s" % pretty_flags(co.co_flags))
|
|
if co.co_consts:
|
|
lines.append("Constants:")
|
|
for i_c in enumerate(co.co_consts):
|
|
lines.append("%4d: %r" % i_c)
|
|
if co.co_names:
|
|
lines.append("Names:")
|
|
for i_n in enumerate(co.co_names):
|
|
lines.append("%4d: %s" % i_n)
|
|
if co.co_varnames:
|
|
lines.append("Variable names:")
|
|
for i_n in enumerate(co.co_varnames):
|
|
lines.append("%4d: %s" % i_n)
|
|
if co.co_freevars:
|
|
lines.append("Free variables:")
|
|
for i_n in enumerate(co.co_freevars):
|
|
lines.append("%4d: %s" % i_n)
|
|
if co.co_cellvars:
|
|
lines.append("Cell variables:")
|
|
for i_n in enumerate(co.co_cellvars):
|
|
lines.append("%4d: %s" % i_n)
|
|
return "\n".join(lines)
|
|
|
|
def show_code(co):
|
|
"""Show details about a code object."""
|
|
print(code_info(co))
|
|
|
|
def disassemble(co, lasti=-1):
|
|
"""Disassemble a code object."""
|
|
code = co.co_code
|
|
labels = findlabels(code)
|
|
linestarts = dict(findlinestarts(co))
|
|
n = len(code)
|
|
i = 0
|
|
extended_arg = 0
|
|
free = None
|
|
while i < n:
|
|
op = code[i]
|
|
if i in linestarts:
|
|
if i > 0:
|
|
print()
|
|
print("%3d" % linestarts[i], end=' ')
|
|
else:
|
|
print(' ', end=' ')
|
|
|
|
if i == lasti: print('-->', end=' ')
|
|
else: print(' ', end=' ')
|
|
if i in labels: print('>>', end=' ')
|
|
else: print(' ', end=' ')
|
|
print(repr(i).rjust(4), end=' ')
|
|
print(opname[op].ljust(20), end=' ')
|
|
i = i+1
|
|
if op >= HAVE_ARGUMENT:
|
|
oparg = code[i] + code[i+1]*256 + extended_arg
|
|
extended_arg = 0
|
|
i = i+2
|
|
if op == EXTENDED_ARG:
|
|
extended_arg = oparg*65536
|
|
print(repr(oparg).rjust(5), end=' ')
|
|
if op in hasconst:
|
|
print('(' + repr(co.co_consts[oparg]) + ')', end=' ')
|
|
elif op in hasname:
|
|
print('(' + co.co_names[oparg] + ')', end=' ')
|
|
elif op in hasjrel:
|
|
print('(to ' + repr(i + oparg) + ')', end=' ')
|
|
elif op in haslocal:
|
|
print('(' + co.co_varnames[oparg] + ')', end=' ')
|
|
elif op in hascompare:
|
|
print('(' + cmp_op[oparg] + ')', end=' ')
|
|
elif op in hasfree:
|
|
if free is None:
|
|
free = co.co_cellvars + co.co_freevars
|
|
print('(' + free[oparg] + ')', end=' ')
|
|
print()
|
|
|
|
def _disassemble_bytes(code, lasti=-1, varnames=None, names=None,
|
|
constants=None):
|
|
labels = findlabels(code)
|
|
n = len(code)
|
|
i = 0
|
|
while i < n:
|
|
op = code[i]
|
|
if i == lasti: print('-->', end=' ')
|
|
else: print(' ', end=' ')
|
|
if i in labels: print('>>', end=' ')
|
|
else: print(' ', end=' ')
|
|
print(repr(i).rjust(4), end=' ')
|
|
print(opname[op].ljust(15), end=' ')
|
|
i = i+1
|
|
if op >= HAVE_ARGUMENT:
|
|
oparg = code[i] + code[i+1]*256
|
|
i = i+2
|
|
print(repr(oparg).rjust(5), end=' ')
|
|
if op in hasconst:
|
|
if constants:
|
|
print('(' + repr(constants[oparg]) + ')', end=' ')
|
|
else:
|
|
print('(%d)'%oparg, end=' ')
|
|
elif op in hasname:
|
|
if names is not None:
|
|
print('(' + names[oparg] + ')', end=' ')
|
|
else:
|
|
print('(%d)'%oparg, end=' ')
|
|
elif op in hasjrel:
|
|
print('(to ' + repr(i + oparg) + ')', end=' ')
|
|
elif op in haslocal:
|
|
if varnames:
|
|
print('(' + varnames[oparg] + ')', end=' ')
|
|
else:
|
|
print('(%d)' % oparg, end=' ')
|
|
elif op in hascompare:
|
|
print('(' + cmp_op[oparg] + ')', end=' ')
|
|
print()
|
|
|
|
def _disassemble_str(source):
|
|
"""Compile the source string, then disassemble the code object."""
|
|
disassemble(_try_compile(source, '<dis>'))
|
|
|
|
disco = disassemble # XXX For backwards compatibility
|
|
|
|
def findlabels(code):
|
|
"""Detect all offsets in a byte code which are jump targets.
|
|
|
|
Return the list of offsets.
|
|
|
|
"""
|
|
labels = []
|
|
n = len(code)
|
|
i = 0
|
|
while i < n:
|
|
op = code[i]
|
|
i = i+1
|
|
if op >= HAVE_ARGUMENT:
|
|
oparg = code[i] + code[i+1]*256
|
|
i = i+2
|
|
label = -1
|
|
if op in hasjrel:
|
|
label = i+oparg
|
|
elif op in hasjabs:
|
|
label = oparg
|
|
if label >= 0:
|
|
if label not in labels:
|
|
labels.append(label)
|
|
return labels
|
|
|
|
def findlinestarts(code):
|
|
"""Find the offsets in a byte code which are start of lines in the source.
|
|
|
|
Generate pairs (offset, lineno) as described in Python/compile.c.
|
|
|
|
"""
|
|
byte_increments = list(code.co_lnotab[0::2])
|
|
line_increments = list(code.co_lnotab[1::2])
|
|
|
|
lastlineno = None
|
|
lineno = code.co_firstlineno
|
|
addr = 0
|
|
for byte_incr, line_incr in zip(byte_increments, line_increments):
|
|
if byte_incr:
|
|
if lineno != lastlineno:
|
|
yield (addr, lineno)
|
|
lastlineno = lineno
|
|
addr += byte_incr
|
|
lineno += line_incr
|
|
if lineno != lastlineno:
|
|
yield (addr, lineno)
|
|
|
|
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")
|
|
dis(code)
|
|
|
|
if __name__ == "__main__":
|
|
_test()
|