diff --git a/Lib/subprocess.py b/Lib/subprocess.py index 36d78180f71..0656c842eef 100644 --- a/Lib/subprocess.py +++ b/Lib/subprocess.py @@ -675,12 +675,12 @@ class Popen(object): return data.decode(encoding) - def __del__(self, sys=sys): + def __del__(self, _maxsize=sys.maxsize, _active=_active): if not self._child_created: # We didn't get to successfully create a child process. return # In case the child hasn't been waited on, check if it's done. - self._internal_poll(_deadstate=sys.maxsize) + self._internal_poll(_deadstate=_maxsize) if self.returncode is None and _active is not None: # Child is still running, keep us alive until we can wait on it. _active.append(self) @@ -883,13 +883,20 @@ class Popen(object): errwrite.Close() - def _internal_poll(self, _deadstate=None): + def _internal_poll(self, _deadstate=None, + _WaitForSingleObject=WaitForSingleObject, + _WAIT_OBJECT_0=WAIT_OBJECT_0, + _GetExitCodeProcess=GetExitCodeProcess): """Check if child process has terminated. Returns returncode - attribute.""" + attribute. + + This method is called by __del__, so it can only refer to objects + in its local scope. + + """ if self.returncode is None: - if(_subprocess.WaitForSingleObject(self._handle, 0) == - _subprocess.WAIT_OBJECT_0): - self.returncode = _subprocess.GetExitCodeProcess(self._handle) + if _WaitForSingleObject(self._handle, 0) == _WAIT_OBJECT_0: + self.returncode = _GetExitCodeProcess(self._handle) return self.returncode @@ -1150,25 +1157,35 @@ class Popen(object): raise child_exception - def _handle_exitstatus(self, sts): - if os.WIFSIGNALED(sts): - self.returncode = -os.WTERMSIG(sts) - elif os.WIFEXITED(sts): - self.returncode = os.WEXITSTATUS(sts) + def _handle_exitstatus(self, sts, _WIFSIGNALED=os.WIFSIGNALED, + _WTERMSIG=os.WTERMSIG, _WIFEXITED=os.WIFEXITED, + _WEXITSTATUS=os.WEXITSTATUS): + # 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) else: # Should never happen raise RuntimeError("Unknown child exit status!") - def _internal_poll(self, _deadstate=None): + def _internal_poll(self, _deadstate=None, _waitpid=os.waitpid, + _WNOHANG=os.WNOHANG, _os_error=os.error): """Check if child process has terminated. Returns returncode - attribute.""" + attribute. + + This method is called by __del__, so it cannot reference anything + outside of the local scope (nor can any methods it calls). + + """ if self.returncode is None: try: - pid, sts = os.waitpid(self.pid, os.WNOHANG) + pid, sts = _waitpid(self.pid, _WNOHANG) if pid == self.pid: self._handle_exitstatus(sts) - except os.error: + except _os_error: if _deadstate is not None: self.returncode = _deadstate return self.returncode diff --git a/Misc/NEWS b/Misc/NEWS index e42566f365e..68bbf31b0b8 100644 --- a/Misc/NEWS +++ b/Misc/NEWS @@ -40,6 +40,9 @@ Core and Builtins Library ------- +- Issue #5099: subprocess.Popen.__del__ no longer references global objects + to prevent issues during interpreter shutdown. + - Issue #8681: Make the zlib module's error messages more informative when the zlib itself doesn't give any detailed explanation.