| /**************************************************************************** |
| ** |
| ** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies). |
| ** All rights reserved. |
| ** Contact: Nokia Corporation (qt-info@nokia.com) |
| ** |
| ** This file is part of the QtCore module of the Qt Toolkit. |
| ** |
| ** $QT_BEGIN_LICENSE:LGPL$ |
| ** GNU Lesser General Public License Usage |
| ** This file may be used under the terms of the GNU Lesser General Public |
| ** License version 2.1 as published by the Free Software Foundation and |
| ** appearing in the file LICENSE.LGPL included in the packaging of this |
| ** file. Please review the following information to ensure the GNU Lesser |
| ** General Public License version 2.1 requirements will be met: |
| ** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html. |
| ** |
| ** In addition, as a special exception, Nokia gives you certain additional |
| ** rights. These rights are described in the Nokia Qt LGPL Exception |
| ** version 1.1, included in the file LGPL_EXCEPTION.txt in this package. |
| ** |
| ** GNU General Public License Usage |
| ** Alternatively, this file may be used under the terms of the GNU General |
| ** Public License version 3.0 as published by the Free Software Foundation |
| ** and appearing in the file LICENSE.GPL included in the packaging of this |
| ** file. Please review the following information to ensure the GNU General |
| ** Public License version 3.0 requirements will be met: |
| ** http://www.gnu.org/copyleft/gpl.html. |
| ** |
| ** Other Usage |
| ** Alternatively, this file may be used in accordance with the terms and |
| ** conditions contained in a signed written agreement between you and Nokia. |
| ** |
| ** |
| ** |
| ** |
| ** |
| ** $QT_END_LICENSE$ |
| ** |
| ****************************************************************************/ |
| |
| #include "qplatformdefs.h" |
| #include "qwaitcondition.h" |
| #include "qmutex.h" |
| #include "qreadwritelock.h" |
| #include "qatomic.h" |
| #include "qstring.h" |
| |
| #include "qmutex_p.h" |
| #include "qreadwritelock_p.h" |
| |
| #include <errno.h> |
| |
| #ifndef QT_NO_THREAD |
| |
| QT_BEGIN_NAMESPACE |
| |
| static void report_error(int code, const char *where, const char *what) |
| { |
| if (code != 0) |
| qWarning("%s: %s failure: %s", where, what, qPrintable(qt_error_string(code))); |
| } |
| |
| |
| |
| class QWaitConditionPrivate { |
| public: |
| pthread_mutex_t mutex; |
| pthread_cond_t cond; |
| int waiters; |
| int wakeups; |
| |
| bool wait(unsigned long time) |
| { |
| int code; |
| forever { |
| if (time != ULONG_MAX) { |
| struct timeval tv; |
| gettimeofday(&tv, 0); |
| |
| timespec ti; |
| ti.tv_nsec = (tv.tv_usec + (time % 1000) * 1000) * 1000; |
| ti.tv_sec = tv.tv_sec + (time / 1000) + (ti.tv_nsec / 1000000000); |
| ti.tv_nsec %= 1000000000; |
| |
| code = pthread_cond_timedwait(&cond, &mutex, &ti); |
| } else { |
| code = pthread_cond_wait(&cond, &mutex); |
| } |
| if (code == 0 && wakeups == 0) { |
| // many vendors warn of spurios wakeups from |
| // pthread_cond_wait(), especially after signal delivery, |
| // even though POSIX doesn't allow for it... sigh |
| continue; |
| } |
| break; |
| } |
| |
| Q_ASSERT_X(waiters > 0, "QWaitCondition::wait", "internal error (waiters)"); |
| --waiters; |
| if (code == 0) { |
| Q_ASSERT_X(wakeups > 0, "QWaitCondition::wait", "internal error (wakeups)"); |
| --wakeups; |
| } |
| report_error(pthread_mutex_unlock(&mutex), "QWaitCondition::wait()", "mutex unlock"); |
| |
| if (code && code != ETIMEDOUT) |
| report_error(code, "QWaitCondition::wait()", "cv wait"); |
| |
| return (code == 0); |
| } |
| }; |
| |
| |
| QWaitCondition::QWaitCondition() |
| { |
| d = new QWaitConditionPrivate; |
| report_error(pthread_mutex_init(&d->mutex, NULL), "QWaitCondition", "mutex init"); |
| report_error(pthread_cond_init(&d->cond, NULL), "QWaitCondition", "cv init"); |
| d->waiters = d->wakeups = 0; |
| } |
| |
| |
| QWaitCondition::~QWaitCondition() |
| { |
| report_error(pthread_cond_destroy(&d->cond), "QWaitCondition", "cv destroy"); |
| report_error(pthread_mutex_destroy(&d->mutex), "QWaitCondition", "mutex destroy"); |
| delete d; |
| } |
| |
| void QWaitCondition::wakeOne() |
| { |
| report_error(pthread_mutex_lock(&d->mutex), "QWaitCondition::wakeOne()", "mutex lock"); |
| d->wakeups = qMin(d->wakeups + 1, d->waiters); |
| report_error(pthread_cond_signal(&d->cond), "QWaitCondition::wakeOne()", "cv signal"); |
| report_error(pthread_mutex_unlock(&d->mutex), "QWaitCondition::wakeOne()", "mutex unlock"); |
| } |
| |
| void QWaitCondition::wakeAll() |
| { |
| report_error(pthread_mutex_lock(&d->mutex), "QWaitCondition::wakeAll()", "mutex lock"); |
| d->wakeups = d->waiters; |
| report_error(pthread_cond_broadcast(&d->cond), "QWaitCondition::wakeAll()", "cv broadcast"); |
| report_error(pthread_mutex_unlock(&d->mutex), "QWaitCondition::wakeAll()", "mutex unlock"); |
| } |
| |
| bool QWaitCondition::wait(QMutex *mutex, unsigned long time) |
| { |
| if (! mutex) |
| return false; |
| if (mutex->d->recursive) { |
| qWarning("QWaitCondition: cannot wait on recursive mutexes"); |
| return false; |
| } |
| |
| report_error(pthread_mutex_lock(&d->mutex), "QWaitCondition::wait()", "mutex lock"); |
| ++d->waiters; |
| mutex->unlock(); |
| |
| bool returnValue = d->wait(time); |
| |
| mutex->lock(); |
| |
| return returnValue; |
| } |
| |
| bool QWaitCondition::wait(QReadWriteLock *readWriteLock, unsigned long time) |
| { |
| if (!readWriteLock || readWriteLock->d->accessCount == 0) |
| return false; |
| if (readWriteLock->d->accessCount < -1) { |
| qWarning("QWaitCondition: cannot wait on QReadWriteLocks with recursive lockForWrite()"); |
| return false; |
| } |
| |
| report_error(pthread_mutex_lock(&d->mutex), "QWaitCondition::wait()", "mutex lock"); |
| ++d->waiters; |
| |
| int previousAccessCount = readWriteLock->d->accessCount; |
| readWriteLock->unlock(); |
| |
| bool returnValue = d->wait(time); |
| |
| if (previousAccessCount < 0) |
| readWriteLock->lockForWrite(); |
| else |
| readWriteLock->lockForRead(); |
| |
| return returnValue; |
| } |
| |
| QT_END_NAMESPACE |
| |
| #endif // QT_NO_THREAD |