78 lines
2.1 KiB
Python
78 lines
2.1 KiB
Python
#!/usr/bin/python
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# -*- coding: utf-8 -*-
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# Copyright 2013 The Plaso Project Authors.
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# Please see the AUTHORS file for details on individual authors.
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#
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# Licensed under the Apache License, Version 2.0 (the "License");
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# you may not use this file except in compliance with the License.
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# You may obtain a copy of the License at
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#
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# http://www.apache.org/licenses/LICENSE-2.0
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#
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# Unless required by applicable law or agreed to in writing, software
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# distributed under the License is distributed on an "AS IS" BASIS,
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# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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# See the License for the specific language governing permissions and
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# limitations under the License.
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"""This file contains buffer related objects used in plaso."""
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class CircularBuffer(object):
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"""Simple circular buffer for storing EventObjects."""
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def __init__(self, size):
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"""Initialize a fixed size circular buffer.
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Args:
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size: An integer indicating the number of elements in the buffer.
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"""
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self._size = size
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self._index = 0
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self._list = []
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def __len__(self):
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"""Return the length (the fixed size)."""
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return self._size
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@property
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def size(self):
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return self._size
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def GetCurrent(self):
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"""Return the current item that index points to."""
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index = self._index - 1
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if index < 0:
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return
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return self._list[index]
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def Clear(self):
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"""Clear all elements in the list."""
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self._list = []
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self._index = 0
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def __iter__(self):
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"""Return all elements from the list."""
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for index in range(0, self._size):
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try:
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yield self._list[(self._index + index) % self._size]
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except IndexError:
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pass
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def Flush(self):
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"""Return a generator for all items and clear the buffer."""
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for item in self:
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yield item
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self.Clear()
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def Append(self, item):
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"""Add an item to the list."""
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if self._index >= self._size:
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self._index = self._index % self._size
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try:
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self._list[self._index] = item
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except IndexError:
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self._list.append(item)
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self._index += 1
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