From 9bd4a245f2ed0ce5a59652976c19ca74e9db518f Mon Sep 17 00:00:00 2001 From: "Gregory P. Smith" Date: Tue, 4 Jan 2011 18:33:38 +0000 Subject: [PATCH] Fix the new bug introduced in the r87710 fix for issue 6643. DummyThread deletes its _block attribute, deal with that. This prevents an uncaught exception in a thread during test_thread. This refactors a bit to better match what I did in the r87727 backport to 2.7. --- Lib/threading.py | 17 +++++++++++++---- 1 file changed, 13 insertions(+), 4 deletions(-) diff --git a/Lib/threading.py b/Lib/threading.py index b586bb0cdcb..392ad141de6 100644 --- a/Lib/threading.py +++ b/Lib/threading.py @@ -395,6 +395,10 @@ class _Event(_Verbose): self._cond = Condition(Lock()) self._flag = False + def _reset_internal_locks(self): + # private! called by Thread._reset_internal_locks by _after_fork() + self._cond.__init__() + def is_set(self): return self._flag @@ -642,6 +646,13 @@ class Thread(_Verbose): # sys.exc_info since it can be changed between instances self._stderr = _sys.stderr + def _reset_internal_locks(self): + # private! Called by _after_fork() to reset our internal locks as + # they may be in an invalid state leading to a deadlock or crash. + if hasattr(self, '_block'): # DummyThread deletes _block + self._block.__init__() + self._started._reset_internal_locks() + def _set_daemon(self): # Overridden in _MainThread and _DummyThread return current_thread().daemon @@ -984,12 +995,11 @@ class _DummyThread(Thread): def __init__(self): Thread.__init__(self, name=_newname("Dummy-%d")) - # Thread.__block consumes an OS-level locking primitive, which + # Thread._block consumes an OS-level locking primitive, which # can never be used by a _DummyThread. Since a _DummyThread # instance is immortal, that's bad, so release this resource. del self._block - self._started.set() self._set_ident() with _active_limbo_lock: @@ -1066,8 +1076,7 @@ def _after_fork(): thread._ident = ident # Any condition variables hanging off of the active thread may # be in an invalid state, so we reinitialize them. - thread._block.__init__() - thread._started._cond.__init__() + thread._reset_internal_locks() new_active[ident] = thread else: # All the others are already stopped.