42 lines
1.2 KiB
Python
42 lines
1.2 KiB
Python
import math
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class Packer:
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def __init__(self, offset: int = 0):
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self._word_cursor = offset
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self._short_cursor = offset
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self._byte_cursor = offset
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self._boundary = offset % 4
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def _next_block(self) -> int:
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self._word_cursor += 4
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return self._word_cursor - 4
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def request_allocation(self, size: int) -> int:
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if size == 0:
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return self._word_cursor
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elif size == 1:
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if self._byte_cursor % 4 == self._boundary:
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self._byte_cursor = self._next_block() + 1
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else:
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self._byte_cursor += 1
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return self._byte_cursor - 1
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elif size == 2:
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if self._short_cursor % 4 == self._boundary:
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self._short_cursor = self._next_block() + 2
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else:
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self._short_cursor += 2
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return self._short_cursor - 2
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else:
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old_cursor = self._word_cursor
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for _ in range(math.ceil(size / 4)):
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self._word_cursor += 4
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return old_cursor
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def notify_skipped(self, no_bytes: int) -> None:
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for _ in range(math.ceil(no_bytes / 4)):
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self.request_allocation(4)
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__all__ = ("Packer", )
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