bpo-40094: Add os.waitstatus_to_exitcode() (GH-19201)
Add os.waitstatus_to_exitcode() function to convert a wait status to an
exitcode.
Suggest waitstatus_to_exitcode() usage in the documentation when
appropriate.
Use waitstatus_to_exitcode() in:
* multiprocessing, os, subprocess and _bootsubprocess modules;
* test.support.wait_process();
* setup.py: run_command();
* and many tests.
diff --git a/Lib/_bootsubprocess.py b/Lib/_bootsubprocess.py
index 9c1912f..014782f 100644
--- a/Lib/_bootsubprocess.py
+++ b/Lib/_bootsubprocess.py
@@ -6,15 +6,6 @@
import os
-def _waitstatus_to_exitcode(status):
- if os.WIFEXITED(status):
- return os.WEXITSTATUS(status)
- elif os.WIFSIGNALED(status):
- return -os.WTERMSIG(status)
- else:
- raise ValueError(f"invalid wait status: {status!r}")
-
-
# distutils.spawn used by distutils.command.build_ext
# calls subprocess.Popen().wait()
class Popen:
@@ -37,7 +28,7 @@
else:
# Parent process
_, status = os.waitpid(pid, 0)
- self.returncode = _waitstatus_to_exitcode(status)
+ self.returncode = os.waitstatus_to_exitcode(status)
return self.returncode
@@ -87,7 +78,7 @@
try:
# system() spawns a shell
status = os.system(cmd)
- exitcode = _waitstatus_to_exitcode(status)
+ exitcode = os.waitstatus_to_exitcode(status)
if exitcode:
raise ValueError(f"Command {cmd!r} returned non-zero "
f"exit status {exitcode!r}")
diff --git a/Lib/multiprocessing/forkserver.py b/Lib/multiprocessing/forkserver.py
index 215ac39..22a911a 100644
--- a/Lib/multiprocessing/forkserver.py
+++ b/Lib/multiprocessing/forkserver.py
@@ -237,14 +237,8 @@
break
child_w = pid_to_fd.pop(pid, None)
if child_w is not None:
- if os.WIFSIGNALED(sts):
- returncode = -os.WTERMSIG(sts)
- else:
- if not os.WIFEXITED(sts):
- raise AssertionError(
- "Child {0:n} status is {1:n}".format(
- pid,sts))
- returncode = os.WEXITSTATUS(sts)
+ returncode = os.waitstatus_to_exitcode(sts)
+
# Send exit code to client process
try:
write_signed(child_w, returncode)
diff --git a/Lib/multiprocessing/popen_fork.py b/Lib/multiprocessing/popen_fork.py
index a65b06f..625981c 100644
--- a/Lib/multiprocessing/popen_fork.py
+++ b/Lib/multiprocessing/popen_fork.py
@@ -30,11 +30,7 @@
# e.errno == errno.ECHILD == 10
return None
if pid == self.pid:
- if os.WIFSIGNALED(sts):
- self.returncode = -os.WTERMSIG(sts)
- else:
- assert os.WIFEXITED(sts), "Status is {:n}".format(sts)
- self.returncode = os.WEXITSTATUS(sts)
+ self.returncode = os.waitstatus_to_exitcode(sts)
return self.returncode
def wait(self, timeout=None):
diff --git a/Lib/os.py b/Lib/os.py
index 8459baa..8acd6f1 100644
--- a/Lib/os.py
+++ b/Lib/os.py
@@ -864,12 +864,8 @@
wpid, sts = waitpid(pid, 0)
if WIFSTOPPED(sts):
continue
- elif WIFSIGNALED(sts):
- return -WTERMSIG(sts)
- elif WIFEXITED(sts):
- return WEXITSTATUS(sts)
- else:
- raise OSError("Not stopped, signaled or exited???")
+
+ return waitstatus_to_exitcode(sts)
def spawnv(mode, file, args):
"""spawnv(mode, file, args) -> integer
diff --git a/Lib/subprocess.py b/Lib/subprocess.py
index c8db387..1eeccea 100644
--- a/Lib/subprocess.py
+++ b/Lib/subprocess.py
@@ -1838,23 +1838,17 @@
raise child_exception_type(err_msg)
- def _handle_exitstatus(self, sts, _WIFSIGNALED=os.WIFSIGNALED,
- _WTERMSIG=os.WTERMSIG, _WIFEXITED=os.WIFEXITED,
- _WEXITSTATUS=os.WEXITSTATUS, _WIFSTOPPED=os.WIFSTOPPED,
- _WSTOPSIG=os.WSTOPSIG):
+ def _handle_exitstatus(self, sts,
+ waitstatus_to_exitcode=os.waitstatus_to_exitcode,
+ _WIFSTOPPED=os.WIFSTOPPED,
+ _WSTOPSIG=os.WSTOPSIG):
"""All callers to this function MUST hold self._waitpid_lock."""
# This method is called (indirectly) by __del__, so it cannot
# refer to anything outside of its local scope.
- if _WIFSIGNALED(sts):
- self.returncode = -_WTERMSIG(sts)
- elif _WIFEXITED(sts):
- self.returncode = _WEXITSTATUS(sts)
- elif _WIFSTOPPED(sts):
+ if _WIFSTOPPED(sts):
self.returncode = -_WSTOPSIG(sts)
else:
- # Should never happen
- raise SubprocessError("Unknown child exit status!")
-
+ self.returncode = waitstatus_to_exitcode(sts)
def _internal_poll(self, _deadstate=None, _waitpid=os.waitpid,
_WNOHANG=os.WNOHANG, _ECHILD=errno.ECHILD):
diff --git a/Lib/test/support/__init__.py b/Lib/test/support/__init__.py
index 7272d47..1f792d8 100644
--- a/Lib/test/support/__init__.py
+++ b/Lib/test/support/__init__.py
@@ -3442,18 +3442,11 @@
sleep = min(sleep * 2, max_sleep)
time.sleep(sleep)
-
- if os.WIFEXITED(status):
- exitcode2 = os.WEXITSTATUS(status)
- elif os.WIFSIGNALED(status):
- exitcode2 = -os.WTERMSIG(status)
- else:
- raise ValueError(f"invalid wait status: {status!r}")
else:
# Windows implementation
pid2, status = os.waitpid(pid, 0)
- exitcode2 = (status >> 8)
+ exitcode2 = os.waitstatus_to_exitcode(status)
if exitcode2 != exitcode:
raise AssertionError(f"process {pid} exited with code {exitcode2}, "
f"but exit code {exitcode} is expected")
diff --git a/Lib/test/test_os.py b/Lib/test/test_os.py
index be85616..142cfea 100644
--- a/Lib/test/test_os.py
+++ b/Lib/test/test_os.py
@@ -2794,6 +2794,35 @@
pid = os.spawnv(os.P_NOWAIT, FakePath(args[0]), args)
support.wait_process(pid, exitcode=0)
+ def test_waitstatus_to_exitcode(self):
+ exitcode = 23
+ filename = support.TESTFN
+ self.addCleanup(support.unlink, filename)
+
+ with open(filename, "w") as fp:
+ print(f'import sys; sys.exit({exitcode})', file=fp)
+ fp.flush()
+ args = [sys.executable, filename]
+ pid = os.spawnv(os.P_NOWAIT, args[0], args)
+
+ pid2, status = os.waitpid(pid, 0)
+ self.assertEqual(os.waitstatus_to_exitcode(status), exitcode)
+ self.assertEqual(pid2, pid)
+
+ # Skip the test on Windows
+ @unittest.skipUnless(hasattr(signal, 'SIGKILL'), 'need signal.SIGKILL')
+ def test_waitstatus_to_exitcode_kill(self):
+ signum = signal.SIGKILL
+ args = [sys.executable, '-c',
+ f'import time; time.sleep({support.LONG_TIMEOUT})']
+ pid = os.spawnv(os.P_NOWAIT, args[0], args)
+
+ os.kill(pid, signum)
+
+ pid2, status = os.waitpid(pid, 0)
+ self.assertEqual(os.waitstatus_to_exitcode(status), -signum)
+ self.assertEqual(pid2, pid)
+
class SpawnTests(unittest.TestCase):
def create_args(self, *, with_env=False, use_bytes=False):
diff --git a/Lib/test/test_popen.py b/Lib/test/test_popen.py
index da01a87..ab1bc77 100644
--- a/Lib/test/test_popen.py
+++ b/Lib/test/test_popen.py
@@ -44,10 +44,11 @@
def test_return_code(self):
self.assertEqual(os.popen("exit 0").close(), None)
+ status = os.popen("exit 42").close()
if os.name == 'nt':
- self.assertEqual(os.popen("exit 42").close(), 42)
+ self.assertEqual(status, 42)
else:
- self.assertEqual(os.popen("exit 42").close(), 42 << 8)
+ self.assertEqual(os.waitstatus_to_exitcode(status), 42)
def test_contextmanager(self):
with os.popen("echo hello") as f:
diff --git a/Lib/test/test_pty.py b/Lib/test/test_pty.py
index ce85f57..aa5c687 100644
--- a/Lib/test/test_pty.py
+++ b/Lib/test/test_pty.py
@@ -200,8 +200,8 @@
## raise TestFailed("Unexpected output from child: %r" % line)
(pid, status) = os.waitpid(pid, 0)
- res = status >> 8
- debug("Child (%d) exited with status %d (%d)." % (pid, res, status))
+ res = os.waitstatus_to_exitcode(status)
+ debug("Child (%d) exited with code %d (status %d)." % (pid, res, status))
if res == 1:
self.fail("Child raised an unexpected exception in os.setsid()")
elif res == 2:
diff --git a/Lib/test/test_wait3.py b/Lib/test/test_wait3.py
index 6e06049..aa166ba 100644
--- a/Lib/test/test_wait3.py
+++ b/Lib/test/test_wait3.py
@@ -30,8 +30,7 @@
time.sleep(0.1)
self.assertEqual(spid, cpid)
- self.assertEqual(status, exitcode << 8,
- "cause = %d, exit = %d" % (status&0xff, status>>8))
+ self.assertEqual(os.waitstatus_to_exitcode(status), exitcode)
self.assertTrue(rusage)
def test_wait3_rusage_initialized(self):
diff --git a/Lib/test/test_wait4.py b/Lib/test/test_wait4.py
index 6c7ebcb..f8d5e13 100644
--- a/Lib/test/test_wait4.py
+++ b/Lib/test/test_wait4.py
@@ -29,8 +29,7 @@
break
time.sleep(0.1)
self.assertEqual(spid, cpid)
- self.assertEqual(status, exitcode << 8,
- "cause = %d, exit = %d" % (status&0xff, status>>8))
+ self.assertEqual(os.waitstatus_to_exitcode(status), exitcode)
self.assertTrue(rusage)
def tearDownModule():