1"""This test checks for correct wait3() behavior. 2""" 3 4import os 5import subprocess 6import sys 7import time 8import unittest 9from test.fork_wait import ForkWait 10from test import support 11 12if not hasattr(os, 'fork'): 13 raise unittest.SkipTest("os.fork not defined") 14 15if not hasattr(os, 'wait3'): 16 raise unittest.SkipTest("os.wait3 not defined") 17 18class Wait3Test(ForkWait): 19 def wait_impl(self, cpid, *, exitcode): 20 # This many iterations can be required, since some previously run 21 # tests (e.g. test_ctypes) could have spawned a lot of children 22 # very quickly. 23 deadline = time.monotonic() + support.SHORT_TIMEOUT 24 while time.monotonic() <= deadline: 25 # wait3() shouldn't hang, but some of the buildbots seem to hang 26 # in the forking tests. This is an attempt to fix the problem. 27 spid, status, rusage = os.wait3(os.WNOHANG) 28 if spid == cpid: 29 break 30 time.sleep(0.1) 31 32 self.assertEqual(spid, cpid) 33 self.assertEqual(os.waitstatus_to_exitcode(status), exitcode) 34 self.assertTrue(rusage) 35 36 def test_wait3_rusage_initialized(self): 37 # Ensure a successful wait3() call where no child was ready to report 38 # its exit status does not return uninitialized memory in the rusage 39 # structure. See bpo-36279. 40 args = [sys.executable, '-c', 'import sys; sys.stdin.read()'] 41 proc = subprocess.Popen(args, stdin=subprocess.PIPE) 42 try: 43 pid, status, rusage = os.wait3(os.WNOHANG) 44 self.assertEqual(0, pid) 45 self.assertEqual(0, status) 46 self.assertEqual(0, sum(rusage)) 47 finally: 48 proc.stdin.close() 49 proc.wait() 50 51 52def tearDownModule(): 53 support.reap_children() 54 55if __name__ == "__main__": 56 unittest.main() 57