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88 lines
2.2 KiB
Python
88 lines
2.2 KiB
Python
#! /usr/bin/env python
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"""Find the maximum recursion limit that prevents core dumps
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This script finds the maximum safe recursion limit on a particular
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platform. If you need to change the recursion limit on your system,
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this script will tell you a safe upper bound. To use the new limit,
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call sys.setrecursionlimit.
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This module implements several ways to create infinite recursion in
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Python. Different implementations end up pushing different numbers of
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C stack frames, depending on how many calls through Python's abstract
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C API occur.
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After each round of tests, it prints a message
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Limit of NNNN is fine.
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It ends when Python causes a segmentation fault because the limit is
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too high. On platforms like Mac and Windows, it should exit with a
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MemoryError.
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NB: A program that does not use __methods__ can set a higher limit.
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"""
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import sys
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class RecursiveBlowup1:
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def __init__(self):
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self.__init__()
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def test_init():
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return RecursiveBlowup1()
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class RecursiveBlowup2:
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def __repr__(self):
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return repr(self)
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def test_repr():
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return repr(RecursiveBlowup2())
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class RecursiveBlowup4:
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def __add__(self, x):
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return x + self
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def test_add():
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return RecursiveBlowup4() + RecursiveBlowup4()
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class RecursiveBlowup5:
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def __getattr__(self, attr):
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return getattr(self, attr)
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def test_getattr():
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return RecursiveBlowup5().attr
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class RecursiveBlowup6:
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def __getitem__(self, item):
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return self[item - 2] + self[item - 1]
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def test_getitem():
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return RecursiveBlowup6()[5]
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def test_recurse():
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return test_recurse()
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def check_limit(n, test_func_name):
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sys.setrecursionlimit(n)
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if test_func_name.startswith("test_"):
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print test_func_name[5:]
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else:
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print test_func_name
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test_func = globals()[test_func_name]
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try:
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test_func()
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except RuntimeError:
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pass
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else:
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print "Yikes!"
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limit = 1000
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while 1:
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check_limit(limit, "test_recurse")
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check_limit(limit, "test_add")
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check_limit(limit, "test_repr")
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check_limit(limit, "test_init")
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check_limit(limit, "test_getattr")
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check_limit(limit, "test_getitem")
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print "Limit of %d is fine" % limit
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limit = limit + 100
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