mirror of
https://git.ugnet.gay/CrossTalk/azul.git
synced 2026-05-27 22:59:49 +00:00
Athena Funderburg
55 lines
1.0 KiB
Python
55 lines
1.0 KiB
Python
from . import buffer # because of circular imports, would've prefered to do `from .buffer import ...` but oh well
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from dataclasses import dataclass
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from typing import Optional
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@dataclass
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class TLV:
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__slots__ = ('type', 'data')
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type: int
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data: bytes
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def __init__(self, type: int, data: bytes | str = b''):
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self.type = type
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if isinstance(data, str):
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self.data = data.encode()
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else:
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self.data = data
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def marshal(self) -> bytes:
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buf = buffer.Buffer()
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buf.write_u16(self.type)
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buf.write_u16(len(self.data))
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buf.write_bytes(self.data)
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return buf.data
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def marshal_tlvs(tlvs: list[TLV]) -> bytes:
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return b''.join([tlv.marshal() for tlv in tlvs])
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def unmarshal_tlvs(data: bytes) -> list[TLV]:
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buf = buffer.Buffer(data)
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tlvs = []
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while len(buf) > 4:
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type = buf.read_u16()
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length = buf.read_u16()
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value = buf.read_bytes(length)
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tlvs.append(TLV(type, value))
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return tlvs
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def find_tlv(tlvs: list[TLV], type: int) -> Optional[TLV]:
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for tlv in tlvs:
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if tlv.type == type:
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return tlv
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return None
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