mirror of https://github.com/morpheus65535/bazarr
245 lines
8.8 KiB
Python
245 lines
8.8 KiB
Python
__all__ = ['fix_js_args']
|
|
|
|
import types
|
|
from collections import namedtuple
|
|
import opcode
|
|
import six
|
|
import sys
|
|
import dis
|
|
|
|
if six.PY3:
|
|
xrange = range
|
|
chr = lambda x: x
|
|
|
|
# Opcode constants used for comparison and replacecment
|
|
LOAD_FAST = opcode.opmap['LOAD_FAST']
|
|
LOAD_GLOBAL = opcode.opmap['LOAD_GLOBAL']
|
|
STORE_FAST = opcode.opmap['STORE_FAST']
|
|
|
|
|
|
def fix_js_args(func):
|
|
'''Use this function when unsure whether func takes this and arguments as its last 2 args.
|
|
It will append 2 args if it does not.'''
|
|
fcode = six.get_function_code(func)
|
|
fargs = fcode.co_varnames[fcode.co_argcount - 2:fcode.co_argcount]
|
|
if fargs == ('this', 'arguments') or fargs == ('arguments', 'var'):
|
|
return func
|
|
code = append_arguments(six.get_function_code(func), ('this', 'arguments'))
|
|
|
|
return types.FunctionType(
|
|
code,
|
|
six.get_function_globals(func),
|
|
func.__name__,
|
|
closure=six.get_function_closure(func))
|
|
|
|
|
|
def append_arguments(code_obj, new_locals):
|
|
co_varnames = code_obj.co_varnames # Old locals
|
|
co_names = code_obj.co_names # Old globals
|
|
co_names += tuple(e for e in new_locals if e not in co_names)
|
|
co_argcount = code_obj.co_argcount # Argument count
|
|
co_code = code_obj.co_code # The actual bytecode as a string
|
|
|
|
# Make one pass over the bytecode to identify names that should be
|
|
# left in code_obj.co_names.
|
|
not_removed = set(opcode.hasname) - set([LOAD_GLOBAL])
|
|
saved_names = set()
|
|
for inst in instructions(code_obj):
|
|
if inst[0] in not_removed:
|
|
saved_names.add(co_names[inst[1]])
|
|
|
|
# Build co_names for the new code object. This should consist of
|
|
# globals that were only accessed via LOAD_GLOBAL
|
|
names = tuple(
|
|
name for name in co_names if name not in set(new_locals) - saved_names)
|
|
|
|
# Build a dictionary that maps the indices of the entries in co_names
|
|
# to their entry in the new co_names
|
|
name_translations = dict(
|
|
(co_names.index(name), i) for i, name in enumerate(names))
|
|
|
|
# Build co_varnames for the new code object. This should consist of
|
|
# the entirety of co_varnames with new_locals spliced in after the
|
|
# arguments
|
|
new_locals_len = len(new_locals)
|
|
varnames = (
|
|
co_varnames[:co_argcount] + new_locals + co_varnames[co_argcount:])
|
|
|
|
# Build the dictionary that maps indices of entries in the old co_varnames
|
|
# to their indices in the new co_varnames
|
|
range1, range2 = xrange(co_argcount), xrange(co_argcount, len(co_varnames))
|
|
varname_translations = dict((i, i) for i in range1)
|
|
varname_translations.update((i, i + new_locals_len) for i in range2)
|
|
|
|
# Build the dictionary that maps indices of deleted entries of co_names
|
|
# to their indices in the new co_varnames
|
|
names_to_varnames = dict(
|
|
(co_names.index(name), varnames.index(name)) for name in new_locals)
|
|
|
|
# Now we modify the actual bytecode
|
|
modified = []
|
|
for inst in instructions(code_obj):
|
|
op, arg = inst.opcode, inst.arg
|
|
# If the instruction is a LOAD_GLOBAL, we have to check to see if
|
|
# it's one of the globals that we are replacing. Either way,
|
|
# update its arg using the appropriate dict.
|
|
if inst.opcode == LOAD_GLOBAL:
|
|
if inst.arg in names_to_varnames:
|
|
op = LOAD_FAST
|
|
arg = names_to_varnames[inst.arg]
|
|
elif inst.arg in name_translations:
|
|
arg = name_translations[inst.arg]
|
|
else:
|
|
raise ValueError("a name was lost in translation")
|
|
# If it accesses co_varnames or co_names then update its argument.
|
|
elif inst.opcode in opcode.haslocal:
|
|
arg = varname_translations[inst.arg]
|
|
elif inst.opcode in opcode.hasname:
|
|
arg = name_translations[inst.arg]
|
|
modified.extend(write_instruction(op, arg))
|
|
if six.PY2:
|
|
code = ''.join(modified)
|
|
args = (co_argcount + new_locals_len,
|
|
code_obj.co_nlocals + new_locals_len, code_obj.co_stacksize,
|
|
code_obj.co_flags, code, code_obj.co_consts, names, varnames,
|
|
code_obj.co_filename, code_obj.co_name,
|
|
code_obj.co_firstlineno, code_obj.co_lnotab,
|
|
code_obj.co_freevars, code_obj.co_cellvars)
|
|
else:
|
|
code = bytes(modified)
|
|
args = (co_argcount + new_locals_len, 0,
|
|
code_obj.co_nlocals + new_locals_len, code_obj.co_stacksize,
|
|
code_obj.co_flags, code, code_obj.co_consts, names, varnames,
|
|
code_obj.co_filename, code_obj.co_name,
|
|
code_obj.co_firstlineno, code_obj.co_lnotab,
|
|
code_obj.co_freevars, code_obj.co_cellvars)
|
|
|
|
# Done modifying codestring - make the code object
|
|
if hasattr(code_obj, "replace"):
|
|
# Python 3.8+
|
|
return code_obj.replace(
|
|
co_argcount=co_argcount + new_locals_len,
|
|
co_nlocals=code_obj.co_nlocals + new_locals_len,
|
|
co_code=code,
|
|
co_names=names,
|
|
co_varnames=varnames)
|
|
else:
|
|
return types.CodeType(*args)
|
|
|
|
|
|
def instructions(code_obj):
|
|
# easy for python 3.4+
|
|
if sys.version_info >= (3, 4):
|
|
for inst in dis.Bytecode(code_obj):
|
|
yield inst
|
|
else:
|
|
# otherwise we have to manually parse
|
|
code = code_obj.co_code
|
|
NewInstruction = namedtuple('Instruction', ('opcode', 'arg'))
|
|
if six.PY2:
|
|
code = map(ord, code)
|
|
i, L = 0, len(code)
|
|
extended_arg = 0
|
|
while i < L:
|
|
op = code[i]
|
|
i += 1
|
|
if op < opcode.HAVE_ARGUMENT:
|
|
yield NewInstruction(op, None)
|
|
continue
|
|
oparg = code[i] + (code[i + 1] << 8) + extended_arg
|
|
extended_arg = 0
|
|
i += 2
|
|
if op == opcode.EXTENDED_ARG:
|
|
extended_arg = oparg << 16
|
|
continue
|
|
yield NewInstruction(op, oparg)
|
|
|
|
|
|
def write_instruction(op, arg):
|
|
if sys.version_info < (3, 6):
|
|
if arg is None:
|
|
return [chr(op)]
|
|
elif arg <= 65536:
|
|
return [chr(op), chr(arg & 255), chr((arg >> 8) & 255)]
|
|
elif arg <= 4294967296:
|
|
return [
|
|
chr(opcode.EXTENDED_ARG),
|
|
chr((arg >> 16) & 255),
|
|
chr((arg >> 24) & 255),
|
|
chr(op),
|
|
chr(arg & 255),
|
|
chr((arg >> 8) & 255)
|
|
]
|
|
else:
|
|
raise ValueError("Invalid oparg: {0} is too large".format(oparg))
|
|
else: # python 3.6+ uses wordcode instead of bytecode and they already supply all the EXTENDEND_ARG ops :)
|
|
if arg is None:
|
|
return [chr(op), 0]
|
|
return [chr(op), arg & 255]
|
|
# the code below is for case when extended args are to be determined automatically
|
|
# if op == opcode.EXTENDED_ARG:
|
|
# return [] # this will be added automatically
|
|
# elif arg < 1 << 8:
|
|
# return [chr(op), arg]
|
|
# elif arg < 1 << 32:
|
|
# subs = [1<<24, 1<<16, 1<<8] # allowed op extension sizes
|
|
# for sub in subs:
|
|
# if arg >= sub:
|
|
# fit = int(arg / sub)
|
|
# return [chr(opcode.EXTENDED_ARG), fit] + write_instruction(op, arg - fit * sub)
|
|
# else:
|
|
# raise ValueError("Invalid oparg: {0} is too large".format(oparg))
|
|
|
|
|
|
def check(code_obj):
|
|
old_bytecode = code_obj.co_code
|
|
insts = list(instructions(code_obj))
|
|
|
|
pos_to_inst = {}
|
|
bytelist = []
|
|
|
|
for inst in insts:
|
|
pos_to_inst[len(bytelist)] = inst
|
|
bytelist.extend(write_instruction(inst.opcode, inst.arg))
|
|
if six.PY2:
|
|
new_bytecode = ''.join(bytelist)
|
|
else:
|
|
new_bytecode = bytes(bytelist)
|
|
if new_bytecode != old_bytecode:
|
|
print(new_bytecode)
|
|
print(old_bytecode)
|
|
for i in range(min(len(new_bytecode), len(old_bytecode))):
|
|
if old_bytecode[i] != new_bytecode[i]:
|
|
while 1:
|
|
if i in pos_to_inst:
|
|
print(pos_to_inst[i])
|
|
print(pos_to_inst[i - 2])
|
|
print(list(map(chr, old_bytecode))[i - 4:i + 8])
|
|
print(bytelist[i - 4:i + 8])
|
|
break
|
|
raise RuntimeError(
|
|
'Your python version made changes to the bytecode')
|
|
|
|
|
|
check(six.get_function_code(check))
|
|
|
|
if __name__ == '__main__':
|
|
x = 'Wrong'
|
|
dick = 3000
|
|
|
|
def func(a):
|
|
print(x, y, z, a)
|
|
print(dick)
|
|
d = (x, )
|
|
for e in (e for e in x):
|
|
print(e)
|
|
return x, y, z
|
|
|
|
func2 = types.FunctionType(
|
|
append_arguments(six.get_function_code(func), ('x', 'y', 'z')),
|
|
six.get_function_globals(func),
|
|
func.__name__,
|
|
closure=six.get_function_closure(func))
|
|
args = (2, 2, 3, 4), 3, 4
|
|
assert func2(1, *args) == args
|