60 lines
1.2 KiB
Python
60 lines
1.2 KiB
Python
from binascii import unhexlify, hexlify
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from collections import Sequence
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class ReadOnlyList(Sequence):
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def __init__(self, lst):
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self.lst = lst
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def __getitem__(self, key):
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return self.lst[key]
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def __len__(self):
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return len(self.lst)
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def subclass_tuple(name, base):
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return type(name, (base,), {'__slots__': ()})
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class cachedproperty(object):
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def __init__(self, f):
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self.f = f
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def __get__(self, obj, type):
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obj = obj or type
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value = self.f(obj)
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setattr(obj, self.f.__name__, value)
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return value
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def bytes_to_int(be_bytes):
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""" Interprets a big-endian sequence of bytes as an integer. """
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return int(hexlify(be_bytes), 16)
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def int_to_bytes(value):
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""" Converts an integer to a big-endian sequence of bytes. """
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length = (value.bit_length() + 7) // 8
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h = '%x' % value
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return unhexlify(('0' * (len(h) % 2) + h).zfill(length * 2))
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def rev_hex(s):
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return hexlify(unhexlify(s)[::-1])
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def int_to_hex(i, length=1):
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s = hex(i)[2:].rstrip('L')
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s = "0" * (2 * length - len(s)) + s
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return rev_hex(s)
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def hex_to_int(s):
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return int(b'0x' + hexlify(s[::-1]), 16)
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def hash_encode(x):
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return hexlify(x[::-1])
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