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