test_ok2/contrib/pygreen/msgstruct.py

30 lines
889 B
Python

from struct import pack, unpack, calcsize
def message(tp, *values):
strtype = type('')
typecodes = ['']
for v in values:
if type(v) is strtype:
typecodes.append('%ds' % len(v))
elif 0 <= v < 256:
typecodes.append('B')
else:
typecodes.append('l')
typecodes = ''.join(typecodes)
assert len(typecodes) < 256
return pack(("!B%dsc" % len(typecodes)) + typecodes,
len(typecodes), typecodes, tp, *values)
def decodemessage(data):
if data:
limit = ord(data[0]) + 1
if len(data) >= limit:
typecodes = "!c" + data[1:limit]
end = limit + calcsize(typecodes)
if len(data) >= end:
return unpack(typecodes, data[limit:end]), data[end:]
#elif end > 1000000:
# raise OverflowError
return None, data