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import struct
def write_int_string(s):
return struct.pack('>i%ds' % len(s), len(s), s)
def write_short_string(s):
return struct.pack('>H%ds' % len(s), len(s), s)
def read_short_string(data, cur):
if len(data) < cur+2:
raise IOError("Not enough data left")
(strLen,) = struct.unpack('>H', data[cur:cur+2])
if strLen == -1:
return (None, cur+2)
cur += 2
if len(data) < cur+strLen:
raise IOError("Not enough data left")
out = data[cur:cur+strLen]
return (out, cur+strLen)
def read_int_string(data, cur):
if len(data) < cur+4:
raise IOError("Not enough data left")
(strLen,) = struct.unpack('>i', data[cur:cur+4])
if strLen == -1:
return (None, cur+4)
cur += 4
if len(data) < cur+strLen:
raise IOError("Not enough data left")
out = data[cur:cur+strLen]
return (out, cur+strLen)
def relative_unpack(fmt, data, cur):
size = struct.calcsize(fmt)
if len(data) < cur+size:
raise IOError("Not enough data left")
out = struct.unpack(fmt, data[cur:cur+size])
return (out, cur+size)
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