diff options
Diffstat (limited to 'src/corelib')
| -rw-r--r-- | src/corelib/kernel/qobject.cpp | 20 |
1 files changed, 16 insertions, 4 deletions
diff --git a/src/corelib/kernel/qobject.cpp b/src/corelib/kernel/qobject.cpp index 6ed3b30917..777f95ef6d 100644 --- a/src/corelib/kernel/qobject.cpp +++ b/src/corelib/kernel/qobject.cpp @@ -1,6 +1,7 @@ /**************************************************************************** ** ** Copyright (C) 2013 Digia Plc and/or its subsidiary(-ies). +** Copyright (C) 2013 Olivier Goffart <ogoffart@woboq.com> ** Contact: http://www.qt-project.org/legal ** ** This file is part of the QtCore module of the Qt Toolkit. @@ -852,9 +853,9 @@ QObject::~QObject() // The destroy operation must happen outside the lock if (c->isSlotObject) { + c->isSlotObject = false; locker.unlock(); c->slotObj->destroyIfLastRef(); - c->isSlotObject = false; locker.relock(); } c->deref(); @@ -869,7 +870,15 @@ QObject::~QObject() d->connectionLists = 0; } - // disconnect all senders + /* Disconnect all senders: + * This loop basically just does + * for (node = d->senders; node; node = node->next) { ... } + * + * We need to temporarily unlock the receiver mutex to destroy the functors or to lock the + * sender's mutex. And when the mutex is released, node->next might be destroyed by another + * thread. That's why we set node->prev to &node, that way, if node is destroyed, node will + * be updated. + */ QObjectPrivate::Connection *node = d->senders; while (node) { QObject *sender = node->sender; @@ -882,6 +891,8 @@ QObject::~QObject() bool needToUnlock = QOrderedMutexLocker::relock(signalSlotMutex, m); //the node has maybe been removed while the mutex was unlocked in relock? if (!node || node->sender != sender) { + // We hold the wrong mutex + Q_ASSERT(needToUnlock); m->unlock(); continue; } @@ -901,11 +912,12 @@ QObject::~QObject() m->unlock(); if (slotObj) { + if (node) + node->prev = &node; locker.unlock(); slotObj->destroyIfLastRef(); locker.relock(); } - } } @@ -3186,9 +3198,9 @@ bool QMetaObjectPrivate::disconnectHelper(QObjectPrivate::Connection *c, c->receiver = 0; if (c->isSlotObject) { + c->isSlotObject = false; senderMutex->unlock(); c->slotObj->destroyIfLastRef(); - c->isSlotObject = false; senderMutex->lock(); } |