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#
# This file is part of pysnmp software.
#
# Copyright (c) 2005-2019, Ilya Etingof <etingof@gmail.com>
# License: http://snmplabs.com/pysnmp/license.html
#
import random
random.seed()
class Integer(object):
"""Return a next value in a reasonably MT-safe manner"""
def __init__(self, maximum, increment=256):
self._maximum = maximum
if increment >= maximum:
increment = maximum
self._increment = increment
self._threshold = increment // 2
e = random.randrange(self._maximum - self._increment)
self._bank = list(range(e, e + self._increment))
def __repr__(self):
return '%s(%d, %d)' % (
self.__class__.__name__, self._maximum, self._increment)
def __call__(self):
v = self._bank.pop(0)
if v % self._threshold:
return v
# Should be MT-safe unless too many (~ increment/2) threads
# bump into this code simultaneously
e = self._bank[-1] + 1
if e > self._maximum:
e = 0
self._bank.extend(range(e, e + self._threshold))
return v
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