From 2097b9e0ef32ab7a0d745edc0f707c615780c006 Mon Sep 17 00:00:00 2001 From: Victor Stinner Date: Tue, 27 Jun 2017 00:00:51 +0200 Subject: [PATCH] [2.7] bpo-30764: test_subprocess uses SuppressCrashReport (#2405) (#2412) * bpo-30764: Backport support.SuppressCrashReport Backport test.support.SuppressCrashReport context-manager from master. Drop the Windows implementation since it depends on msvcrt.CrtSetReportMode() which isn't available on Python 2.7. * bpo-30764: test_subprocess uses SuppressCrashReport (#2405) bpo-30764, bpo-29335: test_child_terminated_in_stopped_state() of test_subprocess now uses support.SuppressCrashReport() to prevent the creation of a core dump on FreeBSD. (cherry picked from commit cdee3f14f7f4c995e7eedb0bf6a67e260c739f7d) --- Lib/test/support/__init__.py | 79 +++++++++++++++++++++++++++++++++++- Lib/test/test_subprocess.py | 51 ++++++++++++----------- 2 files changed, 103 insertions(+), 27 deletions(-) diff --git a/Lib/test/support/__init__.py b/Lib/test/support/__init__.py index ca55d09337..1f280bc7be 100644 --- a/Lib/test/support/__init__.py +++ b/Lib/test/support/__init__.py @@ -23,6 +23,7 @@ import time import struct import sysconfig import types + try: import thread except ImportError: @@ -43,7 +44,8 @@ __all__ = ["Error", "TestFailed", "ResourceDenied", "import_module", "threading_cleanup", "reap_threads", "start_threads", "cpython_only", "check_impl_detail", "get_attribute", "py3k_bytes", "import_fresh_module", "threading_cleanup", "reap_children", - "strip_python_stderr", "IPV6_ENABLED", "run_with_tz"] + "strip_python_stderr", "IPV6_ENABLED", "run_with_tz", + "SuppressCrashReport"] class Error(Exception): """Base class for regression test exceptions.""" @@ -1842,3 +1844,78 @@ def python_is_optimized(): if opt.startswith('-O'): final_opt = opt return final_opt not in ('', '-O0', '-Og') + + +class SuppressCrashReport: + """Try to prevent a crash report from popping up. + + On Windows, don't display the Windows Error Reporting dialog. On UNIX, + disable the creation of coredump file. + """ + old_value = None + old_modes = None + + def __enter__(self): + """On Windows, disable Windows Error Reporting dialogs using + SetErrorMode. + + On UNIX, try to save the previous core file size limit, then set + soft limit to 0. + """ + if sys.platform.startswith('win'): + # TODO: backport the Windows implementation + pass + else: + try: + import resource + except ImportError: + resource = None + + if resource is not None: + try: + self.old_value = resource.getrlimit(resource.RLIMIT_CORE) + resource.setrlimit(resource.RLIMIT_CORE, + (0, self.old_value[1])) + except (ValueError, OSError): + pass + + if sys.platform == 'darwin': + # Check if the 'Crash Reporter' on OSX was configured + # in 'Developer' mode and warn that it will get triggered + # when it is. + # + # This assumes that this context manager is used in tests + # that might trigger the next manager. + cmd = ['/usr/bin/defaults', 'read', + 'com.apple.CrashReporter', 'DialogType'] + proc = subprocess.Popen(cmd, + stdout=subprocess.PIPE, + stderr=subprocess.PIPE) + with proc: + stdout = proc.communicate()[0] + if stdout.strip() == b'developer': + sys.stdout.write("this test triggers the Crash Reporter, " + "that is intentional") + sys.stdout.flush() + + return self + + def __exit__(self, *ignore_exc): + """Restore Windows ErrorMode or core file behavior to initial value.""" + if self.old_value is None: + return + + if sys.platform.startswith('win'): + # TODO: backport the Windows implementation + pass + else: + try: + import resource + except ImportError: + resource = None + + if resource is not None: + try: + resource.setrlimit(resource.RLIMIT_CORE, self.old_value) + except (ValueError, OSError): + pass diff --git a/Lib/test/test_subprocess.py b/Lib/test/test_subprocess.py index 5220891cbb..e0eb6f2a81 100644 --- a/Lib/test/test_subprocess.py +++ b/Lib/test/test_subprocess.py @@ -10,11 +10,14 @@ import tempfile import time import re import sysconfig +import textwrap try: import ctypes except ImportError: ctypes = None +else: + import ctypes.util try: import resource @@ -1262,43 +1265,39 @@ class POSIXProcessTestCase(BaseTestCase): self.assertEqual(p2.returncode, 0, "Unexpected error: " + repr(stderr)) - _libc_file_extensions = { - 'Linux': 'so.6', - 'Darwin': 'dylib', - } - @unittest.skipIf(not ctypes, 'ctypes module required.') - @unittest.skipIf(platform.uname()[0] not in _libc_file_extensions, - 'Test requires a libc this code can load with ctypes.') - @unittest.skipIf(not sys.executable, 'Test requires sys.executable.') + @unittest.skipIf(not ctypes, 'ctypes module required') + @unittest.skipIf(not sys.executable, 'Test requires sys.executable') def test_child_terminated_in_stopped_state(self): """Test wait() behavior when waitpid returns WIFSTOPPED; issue29335.""" PTRACE_TRACEME = 0 # From glibc and MacOS (PT_TRACE_ME). - libc_name = 'libc.' + self._libc_file_extensions[platform.uname()[0]] + libc_name = ctypes.util.find_library('c') libc = ctypes.CDLL(libc_name) if not hasattr(libc, 'ptrace'): - raise unittest.SkipTest('ptrace() required.') - test_ptrace = subprocess.Popen( - [sys.executable, '-c', """if True: - import ctypes - libc = ctypes.CDLL({libc_name!r}) - libc.ptrace({PTRACE_TRACEME}, 0, 0) - """.format(libc_name=libc_name, PTRACE_TRACEME=PTRACE_TRACEME) - ]) - if test_ptrace.wait() != 0: - raise unittest.SkipTest('ptrace() failed - unable to test.') - child = subprocess.Popen( - [sys.executable, '-c', """if True: + raise unittest.SkipTest('ptrace() required') + + code = textwrap.dedent(""" import ctypes + from test.support import SuppressCrashReport + libc = ctypes.CDLL({libc_name!r}) libc.ptrace({PTRACE_TRACEME}, 0, 0) - libc.printf(ctypes.c_char_p(0xdeadbeef)) # Crash the process. - """.format(libc_name=libc_name, PTRACE_TRACEME=PTRACE_TRACEME) - ]) + """.format(libc_name=libc_name, PTRACE_TRACEME=PTRACE_TRACEME)) + + child = subprocess.Popen([sys.executable, '-c', code]) + if child.wait() != 0: + raise unittest.SkipTest('ptrace() failed - unable to test') + + code += textwrap.dedent(""" + with SuppressCrashReport(): + # Crash the process + libc.printf(ctypes.c_char_p(0xdeadbeef)) # Crash the process. + """) + child = subprocess.Popen([sys.executable, '-c', code]) try: returncode = child.wait() - except Exception as e: + except: child.kill() # Clean up the hung stopped process. - raise e + raise self.assertNotEqual(0, returncode) self.assertLess(returncode, 0) # signal death, likely SIGSEGV. -- 2.50.1