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[swfinterp] Extend tests and fix parsing

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This commit is contained in:
Philipp Hagemeister 2014-07-20 00:03:54 +02:00
parent 0cb2056304
commit e75c24e889
4 changed files with 70 additions and 15 deletions
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47
youtube_dl/swfinterp.py
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@ -39,6 +39,16 @@ def _extract_tags(file_contents):
pos += tag_len
class _AVM_Object(object):
def __init__(self, value=None, name_hint=None):
self.value = value
self.name_hint = name_hint
def __repr__(self):
nh = '' if self.name_hint is None else (' %s' % self.name_hint)
return 'AVMObject%s(%r)' % (nh, self.value)
class _AVMClass_Object(object):
def __init__(self, avm_class):
self.avm_class = avm_class
@ -92,8 +102,8 @@ def _s32(reader):
def _s24(reader):
bs = reader.read(3)
assert len(bs) == 3
first_byte = b'\xff' if (ord(bs[0:1]) >= 0x80) else b'\x00'
return struct.unpack('!i', first_byte + bs)
last_byte = b'\xff' if (ord(bs[2:3]) >= 0x80) else b'\x00'
return struct.unpack('<i', bs + last_byte)[0]
def _read_string(reader):
@ -341,8 +351,9 @@ class SWFInterpreter(object):
u30 = lambda: _u30(coder)
print('Invoking %s.%s(%r)' % (avm_class.name, func_name, tuple(args)))
registers = ['(this)'] + list(args) + [None] * m.local_count
registers = [avm_class.variables] + list(args) + [None] * m.local_count
stack = []
scopes = collections.deque([avm_class.variables])
while True:
opcode = _read_byte(coder)
print('opcode: %r, stack(%d): %r' % (opcode, len(stack), stack))
@ -351,6 +362,11 @@ class SWFInterpreter(object):
value = stack.pop()
if value:
coder.seek(coder.tell() + offset)
elif opcode == 18: # iffalse
offset = s24()
value = stack.pop()
if not value:
coder.seek(coder.tell() + offset)
elif opcode == 36: # pushbyte
v = _read_byte(coder)
stack.append(v)
@ -361,9 +377,8 @@ class SWFInterpreter(object):
idx = u30()
stack.append(constant_strings[idx])
elif opcode == 48: # pushscope
# We don't implement the scope register, so we'll just
# ignore the popped value
new_scope = stack.pop()
scopes.append(new_scope)
elif opcode == 70: # callproperty
index = u30()
mname = self.multinames[index]
@ -435,20 +450,28 @@ class SWFInterpreter(object):
arr.append(stack.pop())
arr = arr[::-1]
stack.append(arr)
elif opcode == 93: # findpropstrict
index = u30()
mname = self.multinames[index]
res = self.extract_function(avm_class, mname)
stack.append(res)
elif opcode == 94: # findproperty
index = u30()
mname = self.multinames[index]
res = avm_class.variables.get(mname)
for s in reversed(scopes):
if mname in s:
res = s
break
else:
res = scopes[0]
stack.append(res)
elif opcode == 96: # getlex
index = u30()
mname = self.multinames[index]
res = avm_class.variables.get(mname, None)
for s in reversed(scopes):
if mname in s:
scope = s
break
else:
scope = scopes[0]
# I cannot find where static variables are initialized
# so let's just return None
res = scope.get(mname)
stack.append(res)
elif opcode == 97: # setproperty
index = u30()