mirror of
https://github.com/DeclanHoare/shiftgears.git
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31 lines
908 B
Python
31 lines
908 B
Python
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import struct
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from twisted.internet.protocol import Protocol
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s32 = struct.Struct("<i")
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class PayloadStream(Protocol):
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"""'Payloads' are length-prefixed binary blobs used in NetSockets."""
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def __init__(self):
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self.__length = None
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self.__buffer = b""
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def dataReceived(self, data):
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self.__buffer += data
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while True:
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if self.__length is None and len(self.__buffer) >= 4:
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self.__length = s32.unpack(self.__buffer[:4])[0]
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self.__buffer = self.__buffer[4:]
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if self.__length < 0:
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raise ValueError(f"Invalid (negative) payload length {self.__length}")
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if self.__length is not None and len(self.__buffer) >= self.__length:
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payload = self.__buffer[:self.__length]
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self.__buffer = self.__buffer[self.__length:]
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self.__length = None
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self.payloadReceived(payload)
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continue
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break
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def sendPayload(self, data):
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self.transport.write(s32.pack(len(data)) + data)
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