cpython/Lib/test/libregrtest/refleak.py

295 lines
8.3 KiB
Python

import errno
import os
import re
import sys
import warnings
from inspect import isabstract
from test import support
try:
MAXFD = os.sysconf("SC_OPEN_MAX")
except Exception:
MAXFD = 256
def fd_count():
"""Count the number of open file descriptors"""
if sys.platform.startswith(('linux', 'freebsd')):
try:
names = os.listdir("/proc/self/fd")
return len(names)
except FileNotFoundError:
pass
count = 0
for fd in range(MAXFD):
try:
# Prefer dup() over fstat(). fstat() can require input/output
# whereas dup() doesn't.
fd2 = os.dup(fd)
except OSError as e:
if e.errno != errno.EBADF:
raise
else:
os.close(fd2)
count += 1
return count
def dash_R(the_module, test, indirect_test, huntrleaks):
"""Run a test multiple times, looking for reference leaks.
Returns:
False if the test didn't leak references; True if we detected refleaks.
"""
# This code is hackish and inelegant, but it seems to do the job.
import copyreg
import collections.abc
if not hasattr(sys, 'gettotalrefcount'):
raise Exception("Tracking reference leaks requires a debug build "
"of Python")
# Save current values for dash_R_cleanup() to restore.
fs = warnings.filters[:]
ps = copyreg.dispatch_table.copy()
pic = sys.path_importer_cache.copy()
try:
import zipimport
except ImportError:
zdc = None # Run unmodified on platforms without zipimport support
else:
zdc = zipimport._zip_directory_cache.copy()
abcs = {}
for abc in [getattr(collections.abc, a) for a in collections.abc.__all__]:
if not isabstract(abc):
continue
for obj in abc.__subclasses__() + [abc]:
abcs[obj] = obj._abc_registry.copy()
# bpo-31217: Integer pool to get a single integer object for the same
# value. The pool is used to prevent false alarm when checking for memory
# block leaks. Fill the pool with values in -1000..1000 which are the most
# common (reference, memory block, file descriptor) differences.
int_pool = {value: value for value in range(-1000, 1000)}
def get_pooled_int(value):
return int_pool.setdefault(value, value)
nwarmup, ntracked, fname = huntrleaks
fname = os.path.join(support.SAVEDCWD, fname)
repcount = nwarmup + ntracked
rc_deltas = [0] * repcount
alloc_deltas = [0] * repcount
fd_deltas = [0] * repcount
print("beginning", repcount, "repetitions", file=sys.stderr)
print(("1234567890"*(repcount//10 + 1))[:repcount], file=sys.stderr,
flush=True)
# initialize variables to make pyflakes quiet
rc_before = alloc_before = fd_before = 0
for i in range(repcount):
indirect_test()
alloc_after, rc_after, fd_after = dash_R_cleanup(fs, ps, pic, zdc,
abcs)
print('.', end='', file=sys.stderr, flush=True)
if i >= nwarmup:
rc_deltas[i] = get_pooled_int(rc_after - rc_before)
alloc_deltas[i] = get_pooled_int(alloc_after - alloc_before)
fd_deltas[i] = get_pooled_int(fd_after - fd_before)
alloc_before = alloc_after
rc_before = rc_after
fd_before = fd_after
print(file=sys.stderr)
# These checkers return False on success, True on failure
def check_rc_deltas(deltas):
# Checker for reference counters and memomry blocks.
#
# bpo-30776: Try to ignore false positives:
#
# [3, 0, 0]
# [0, 1, 0]
# [8, -8, 1]
#
# Expected leaks:
#
# [5, 5, 6]
# [10, 1, 1]
return all(delta >= 1 for delta in deltas)
def check_fd_deltas(deltas):
return any(deltas)
failed = False
for deltas, item_name, checker in [
(rc_deltas, 'references', check_rc_deltas),
(alloc_deltas, 'memory blocks', check_rc_deltas),
(fd_deltas, 'file descriptors', check_fd_deltas)
]:
# ignore warmup runs
deltas = deltas[nwarmup:]
if checker(deltas):
msg = '%s leaked %s %s, sum=%s' % (
test, deltas, item_name, sum(deltas))
print(msg, file=sys.stderr, flush=True)
with open(fname, "a") as refrep:
print(msg, file=refrep)
refrep.flush()
failed = True
return failed
def dash_R_cleanup(fs, ps, pic, zdc, abcs):
import gc, copyreg
import collections.abc
from weakref import WeakSet
# Restore some original values.
warnings.filters[:] = fs
copyreg.dispatch_table.clear()
copyreg.dispatch_table.update(ps)
sys.path_importer_cache.clear()
sys.path_importer_cache.update(pic)
try:
import zipimport
except ImportError:
pass # Run unmodified on platforms without zipimport support
else:
zipimport._zip_directory_cache.clear()
zipimport._zip_directory_cache.update(zdc)
# clear type cache
sys._clear_type_cache()
# Clear ABC registries, restoring previously saved ABC registries.
abs_classes = [getattr(collections.abc, a) for a in collections.abc.__all__]
abs_classes = filter(isabstract, abs_classes)
if 'typing' in sys.modules:
t = sys.modules['typing']
# These classes require special treatment because they do not appear
# in direct subclasses of collections.abc classes
abs_classes = list(abs_classes) + [t.ChainMap, t.Counter, t.DefaultDict]
for abc in abs_classes:
for obj in abc.__subclasses__() + [abc]:
obj._abc_registry = abcs.get(obj, WeakSet()).copy()
obj._abc_cache.clear()
obj._abc_negative_cache.clear()
clear_caches()
# Collect cyclic trash and read memory statistics immediately after.
func1 = sys.getallocatedblocks
func2 = sys.gettotalrefcount
gc.collect()
return func1(), func2(), fd_count()
def clear_caches():
import gc
# Clear the warnings registry, so they can be displayed again
for mod in sys.modules.values():
if hasattr(mod, '__warningregistry__'):
del mod.__warningregistry__
# Flush standard output, so that buffered data is sent to the OS and
# associated Python objects are reclaimed.
for stream in (sys.stdout, sys.stderr, sys.__stdout__, sys.__stderr__):
if stream is not None:
stream.flush()
# Clear assorted module caches.
# Don't worry about resetting the cache if the module is not loaded
try:
distutils_dir_util = sys.modules['distutils.dir_util']
except KeyError:
pass
else:
distutils_dir_util._path_created.clear()
re.purge()
try:
_strptime = sys.modules['_strptime']
except KeyError:
pass
else:
_strptime._regex_cache.clear()
try:
urllib_parse = sys.modules['urllib.parse']
except KeyError:
pass
else:
urllib_parse.clear_cache()
try:
urllib_request = sys.modules['urllib.request']
except KeyError:
pass
else:
urllib_request.urlcleanup()
try:
linecache = sys.modules['linecache']
except KeyError:
pass
else:
linecache.clearcache()
try:
mimetypes = sys.modules['mimetypes']
except KeyError:
pass
else:
mimetypes._default_mime_types()
try:
filecmp = sys.modules['filecmp']
except KeyError:
pass
else:
filecmp._cache.clear()
try:
struct = sys.modules['struct']
except KeyError:
pass
else:
struct._clearcache()
try:
doctest = sys.modules['doctest']
except KeyError:
pass
else:
doctest.master = None
try:
ctypes = sys.modules['ctypes']
except KeyError:
pass
else:
ctypes._reset_cache()
try:
typing = sys.modules['typing']
except KeyError:
pass
else:
for f in typing._cleanups:
f()
gc.collect()
def warm_caches():
# char cache
s = bytes(range(256))
for i in range(256):
s[i:i+1]
# unicode cache
[chr(i) for i in range(256)]
# int cache
list(range(-5, 257))