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39 lines
1009 B
Python
39 lines
1009 B
Python
import sys
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from . import consts
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def to_int_by_words(array: bytes) -> int:
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"""
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Converts array of bytes into an int by reading word size
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of bytes then converted to int using the system's endianness.
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"""
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assert len(array) % consts.WORD_SIZE == 0
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n = 0
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for i in range(0, len(array), consts.WORD_SIZE):
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n = (n << (consts.WORD_SIZE * 8)) + int.from_bytes(
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array[i : i + consts.WORD_SIZE], sys.byteorder
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)
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return n
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def to_bytes_by_words(n: int, length: int) -> bytes:
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"""
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Converting int back to bytes by words.
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"""
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mask = (1 << (consts.WORD_SIZE * 8)) - 1
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array = bytes()
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for i in reversed(range(0, length, consts.WORD_SIZE)):
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array = array + ((n >> (i * 8)) & mask).to_bytes(
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consts.WORD_SIZE, sys.byteorder
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)
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return array
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def int_to_word(n: int) -> bytes:
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return n.to_bytes(consts.WORD_SIZE, sys.byteorder)
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def word_to_int(b: bytes) -> int:
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return int.from_bytes(b, sys.byteorder)
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