diff --git a/Doc/library/test.rst b/Doc/library/test.rst index 0aae14c15a6104..9fdb21b8badbbf 100644 --- a/Doc/library/test.rst +++ b/Doc/library/test.rst @@ -1384,6 +1384,13 @@ The :mod:`test.support.threading_helper` module provides support for threading t .. versionadded:: 3.8 +.. function:: run_concurrently(worker_func, nthreads, args=(), kwargs={}) + + Run the worker function concurrently in multiple threads. + Re-raises an exception if any thread raises one, after all threads have + finished. + + :mod:`test.support.os_helper` --- Utilities for os tests ======================================================================== diff --git a/Lib/test/support/threading_helper.py b/Lib/test/support/threading_helper.py index afa25a76f63829..3e04c344a0d66f 100644 --- a/Lib/test/support/threading_helper.py +++ b/Lib/test/support/threading_helper.py @@ -248,3 +248,27 @@ def requires_working_threading(*, module=False): raise unittest.SkipTest(msg) else: return unittest.skipUnless(can_start_thread, msg) + + +def run_concurrently(worker_func, nthreads, args=(), kwargs={}): + """ + Run the worker function concurrently in multiple threads. + """ + barrier = threading.Barrier(nthreads) + + def wrapper_func(*args, **kwargs): + # Wait for all threads to reach this point before proceeding. + barrier.wait() + worker_func(*args, **kwargs) + + with catch_threading_exception() as cm: + workers = [ + threading.Thread(target=wrapper_func, args=args, kwargs=kwargs) + for _ in range(nthreads) + ] + with start_threads(workers): + pass + + # If a worker thread raises an exception, re-raise it. + if cm.exc_value is not None: + raise cm.exc_value diff --git a/Lib/test/test_free_threading/test_grp.py b/Lib/test/test_free_threading/test_grp.py new file mode 100644 index 00000000000000..1a47a9757702be --- /dev/null +++ b/Lib/test/test_free_threading/test_grp.py @@ -0,0 +1,35 @@ +import unittest + +from test.support import import_helper, threading_helper +from test.support.threading_helper import run_concurrently + +grp = import_helper.import_module("grp") + +from test import test_grp + + +NTHREADS = 10 + + +@threading_helper.requires_working_threading() +class TestGrp(unittest.TestCase): + def setUp(self): + self.test_grp = test_grp.GroupDatabaseTestCase() + + def test_racing_test_values(self): + # test_grp.test_values() calls grp.getgrall() and checks the entries + run_concurrently( + worker_func=self.test_grp.test_values, nthreads=NTHREADS + ) + + def test_racing_test_values_extended(self): + # test_grp.test_values_extended() calls grp.getgrall(), grp.getgrgid(), + # grp.getgrnam() and checks the entries + run_concurrently( + worker_func=self.test_grp.test_values_extended, + nthreads=NTHREADS, + ) + + +if __name__ == "__main__": + unittest.main() diff --git a/Lib/test/test_free_threading/test_heapq.py b/Lib/test/test_free_threading/test_heapq.py index ee7adfb2b78d83..d771333ffcc9e0 100644 --- a/Lib/test/test_free_threading/test_heapq.py +++ b/Lib/test/test_free_threading/test_heapq.py @@ -3,10 +3,11 @@ import heapq from enum import Enum -from threading import Thread, Barrier, Lock +from threading import Barrier, Lock from random import shuffle, randint from test.support import threading_helper +from test.support.threading_helper import run_concurrently from test import test_heapq @@ -28,8 +29,8 @@ def test_racing_heapify(self): heap = list(range(OBJECT_COUNT)) shuffle(heap) - self.run_concurrently( - worker_func=heapq.heapify, args=(heap,), nthreads=NTHREADS + run_concurrently( + worker_func=heapq.heapify, nthreads=NTHREADS, args=(heap,) ) self.test_heapq.check_invariant(heap) @@ -40,8 +41,8 @@ def heappush_func(heap): for item in reversed(range(OBJECT_COUNT)): heapq.heappush(heap, item) - self.run_concurrently( - worker_func=heappush_func, args=(heap,), nthreads=NTHREADS + run_concurrently( + worker_func=heappush_func, nthreads=NTHREADS, args=(heap,) ) self.test_heapq.check_invariant(heap) @@ -61,10 +62,10 @@ def heappop_func(heap, pop_count): # Each local list should be sorted self.assertTrue(self.is_sorted_ascending(local_list)) - self.run_concurrently( + run_concurrently( worker_func=heappop_func, - args=(heap, per_thread_pop_count), nthreads=NTHREADS, + args=(heap, per_thread_pop_count), ) self.assertEqual(len(heap), 0) @@ -77,10 +78,10 @@ def heappushpop_func(heap, pushpop_items): popped_item = heapq.heappushpop(heap, item) self.assertTrue(popped_item <= item) - self.run_concurrently( + run_concurrently( worker_func=heappushpop_func, - args=(heap, pushpop_items), nthreads=NTHREADS, + args=(heap, pushpop_items), ) self.assertEqual(len(heap), OBJECT_COUNT) self.test_heapq.check_invariant(heap) @@ -93,10 +94,10 @@ def heapreplace_func(heap, replace_items): for item in replace_items: heapq.heapreplace(heap, item) - self.run_concurrently( + run_concurrently( worker_func=heapreplace_func, - args=(heap, replace_items), nthreads=NTHREADS, + args=(heap, replace_items), ) self.assertEqual(len(heap), OBJECT_COUNT) self.test_heapq.check_invariant(heap) @@ -105,8 +106,8 @@ def test_racing_heapify_max(self): max_heap = list(range(OBJECT_COUNT)) shuffle(max_heap) - self.run_concurrently( - worker_func=heapq.heapify_max, args=(max_heap,), nthreads=NTHREADS + run_concurrently( + worker_func=heapq.heapify_max, nthreads=NTHREADS, args=(max_heap,) ) self.test_heapq.check_max_invariant(max_heap) @@ -117,8 +118,8 @@ def heappush_max_func(max_heap): for item in range(OBJECT_COUNT): heapq.heappush_max(max_heap, item) - self.run_concurrently( - worker_func=heappush_max_func, args=(max_heap,), nthreads=NTHREADS + run_concurrently( + worker_func=heappush_max_func, nthreads=NTHREADS, args=(max_heap,) ) self.test_heapq.check_max_invariant(max_heap) @@ -138,10 +139,10 @@ def heappop_max_func(max_heap, pop_count): # Each local list should be sorted self.assertTrue(self.is_sorted_descending(local_list)) - self.run_concurrently( + run_concurrently( worker_func=heappop_max_func, - args=(max_heap, per_thread_pop_count), nthreads=NTHREADS, + args=(max_heap, per_thread_pop_count), ) self.assertEqual(len(max_heap), 0) @@ -154,10 +155,10 @@ def heappushpop_max_func(max_heap, pushpop_items): popped_item = heapq.heappushpop_max(max_heap, item) self.assertTrue(popped_item >= item) - self.run_concurrently( + run_concurrently( worker_func=heappushpop_max_func, - args=(max_heap, pushpop_items), nthreads=NTHREADS, + args=(max_heap, pushpop_items), ) self.assertEqual(len(max_heap), OBJECT_COUNT) self.test_heapq.check_max_invariant(max_heap) @@ -170,10 +171,10 @@ def heapreplace_max_func(max_heap, replace_items): for item in replace_items: heapq.heapreplace_max(max_heap, item) - self.run_concurrently( + run_concurrently( worker_func=heapreplace_max_func, - args=(max_heap, replace_items), nthreads=NTHREADS, + args=(max_heap, replace_items), ) self.assertEqual(len(max_heap), OBJECT_COUNT) self.test_heapq.check_max_invariant(max_heap) @@ -203,7 +204,7 @@ def worker(): except IndexError: pass - self.run_concurrently(worker, (), n_threads * 2) + run_concurrently(worker, n_threads * 2) @staticmethod def is_sorted_ascending(lst): @@ -241,27 +242,6 @@ def create_random_list(a, b, size): """ return [randint(-a, b) for _ in range(size)] - def run_concurrently(self, worker_func, args, nthreads): - """ - Run the worker function concurrently in multiple threads. - """ - barrier = Barrier(nthreads) - - def wrapper_func(*args): - # Wait for all threads to reach this point before proceeding. - barrier.wait() - worker_func(*args) - - with threading_helper.catch_threading_exception() as cm: - workers = ( - Thread(target=wrapper_func, args=args) for _ in range(nthreads) - ) - with threading_helper.start_threads(workers): - pass - - # Worker threads should not raise any exceptions - self.assertIsNone(cm.exc_value) - if __name__ == "__main__": unittest.main() diff --git a/Misc/NEWS.d/next/Core_and_Builtins/2025-06-12-00-03-34.gh-issue-116738.iBBAdo.rst b/Misc/NEWS.d/next/Core_and_Builtins/2025-06-12-00-03-34.gh-issue-116738.iBBAdo.rst new file mode 100644 index 00000000000000..2a1ed2944d8ddf --- /dev/null +++ b/Misc/NEWS.d/next/Core_and_Builtins/2025-06-12-00-03-34.gh-issue-116738.iBBAdo.rst @@ -0,0 +1 @@ +Make functions in :mod:`grp` thread-safe on the :term:`free threaded ` build. diff --git a/Modules/grpmodule.c b/Modules/grpmodule.c index 29da9936b65504..652958618a2c4c 100644 --- a/Modules/grpmodule.c +++ b/Modules/grpmodule.c @@ -55,6 +55,11 @@ get_grp_state(PyObject *module) static struct PyModuleDef grpmodule; +/* Mutex to protect calls to getgrgid(), getgrnam(), and getgrent(). + * These functions return pointer to static data structure, which + * may be overwritten by any subsequent calls. */ +static PyMutex group_db_mutex = {0}; + #define DEFAULT_BUFFER_SIZE 1024 static PyObject * @@ -168,9 +173,15 @@ grp_getgrgid_impl(PyObject *module, PyObject *id) Py_END_ALLOW_THREADS #else + PyMutex_Lock(&group_db_mutex); + // The getgrgid() function need not be thread-safe. + // https://pubs.opengroup.org/onlinepubs/9699919799/functions/getgrgid.html p = getgrgid(gid); #endif if (p == NULL) { +#ifndef HAVE_GETGRGID_R + PyMutex_Unlock(&group_db_mutex); +#endif PyMem_RawFree(buf); if (nomem == 1) { return PyErr_NoMemory(); @@ -185,6 +196,8 @@ grp_getgrgid_impl(PyObject *module, PyObject *id) retval = mkgrent(module, p); #ifdef HAVE_GETGRGID_R PyMem_RawFree(buf); +#else + PyMutex_Unlock(&group_db_mutex); #endif return retval; } @@ -249,9 +262,15 @@ grp_getgrnam_impl(PyObject *module, PyObject *name) Py_END_ALLOW_THREADS #else + PyMutex_Lock(&group_db_mutex); + // The getgrnam() function need not be thread-safe. + // https://pubs.opengroup.org/onlinepubs/9699919799/functions/getgrnam.html p = getgrnam(name_chars); #endif if (p == NULL) { +#ifndef HAVE_GETGRNAM_R + PyMutex_Unlock(&group_db_mutex); +#endif if (nomem == 1) { PyErr_NoMemory(); } @@ -261,6 +280,9 @@ grp_getgrnam_impl(PyObject *module, PyObject *name) goto out; } retval = mkgrent(module, p); +#ifndef HAVE_GETGRNAM_R + PyMutex_Unlock(&group_db_mutex); +#endif out: PyMem_RawFree(buf); Py_DECREF(bytes); @@ -285,8 +307,7 @@ grp_getgrall_impl(PyObject *module) return NULL; } - static PyMutex getgrall_mutex = {0}; - PyMutex_Lock(&getgrall_mutex); + PyMutex_Lock(&group_db_mutex); setgrent(); struct group *p; @@ -306,7 +327,7 @@ grp_getgrall_impl(PyObject *module) done: endgrent(); - PyMutex_Unlock(&getgrall_mutex); + PyMutex_Unlock(&group_db_mutex); return d; } diff --git a/Tools/c-analyzer/cpython/ignored.tsv b/Tools/c-analyzer/cpython/ignored.tsv index 15b18f5286b399..64a9f11a944176 100644 --- a/Tools/c-analyzer/cpython/ignored.tsv +++ b/Tools/c-analyzer/cpython/ignored.tsv @@ -167,6 +167,7 @@ Python/sysmodule.c - _preinit_xoptions - # XXX need race protection? Modules/faulthandler.c faulthandler_dump_traceback reentrant - Modules/faulthandler.c faulthandler_dump_c_stack reentrant - +Modules/grpmodule.c - group_db_mutex - Python/pylifecycle.c _Py_FatalErrorFormat reentrant - Python/pylifecycle.c fatal_error reentrant -