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+/****************************************************************************
+**
+** 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.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the Technology Preview License Agreement accompanying
+** this package.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, 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.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "qtconcurrentexception.h"
+
+#ifndef QT_NO_QFUTURE
+#ifndef QT_NO_EXCEPTIONS
+
+QT_BEGIN_NAMESPACE
+
+/*!
+ \class QtConcurrent::Exception
+ \brief The Exception class provides a base class for exceptions that can transferred across threads.
+ \since 4.4
+
+ Qt Concurrent supports throwing and catching exceptions across thread
+ boundaries, provided that the exception inherit from QtConcurrent::Exception
+ and implement two helper functions:
+
+ \snippet doc/src/snippets/code/src_corelib_concurrent_qtconcurrentexception.cpp 0
+
+ QtConcurrent::Exception subclasses must be thrown by value and
+ caught by reference:
+
+ \snippet doc/src/snippets/code/src_corelib_concurrent_qtconcurrentexception.cpp 1
+
+ If you throw an exception that is not a subclass of QtConcurrent::Exception,
+ the Qt Concurrent functions will throw a QtConcurrent::UnhandledException
+ in the receiver thread.
+
+ When using QFuture, transferred exceptions will be thrown when calling the following functions:
+ \list
+ \o QFuture::waitForFinished()
+ \o QFuture::result()
+ \o QFuture::resultAt()
+ \o QFuture::results()
+ \endlist
+*/
+
+/*!
+ \fn QtConcurrent::Exception::raise() const
+ In your QtConcurrent::Exception subclass, reimplement raise() like this:
+
+ \snippet doc/src/snippets/code/src_corelib_concurrent_qtconcurrentexception.cpp 2
+*/
+
+/*!
+ \fn QtConcurrent::Exception::clone() const
+ In your QtConcurrent::Exception subclass, reimplement clone() like this:
+
+ \snippet doc/src/snippets/code/src_corelib_concurrent_qtconcurrentexception.cpp 3
+*/
+
+/*!
+ \class QtConcurrent::UnhandledException
+
+ \brief The UnhandledException class represents an unhandled exception in a worker thread.
+ \since 4.4
+
+ If a worker thread throws an exception that is not a subclass of QtConcurrent::Exception,
+ the Qt Concurrent functions will throw a QtConcurrent::UnhandledException
+ on the receiver thread side.
+
+ Inheriting from this class is not supported.
+*/
+
+/*!
+ \fn QtConcurrent::UnhandledException::raise() const
+ \internal
+*/
+
+/*!
+ \fn QtConcurrent::UnhandledException::clone() const
+ \internal
+*/
+
+namespace QtConcurrent
+{
+
+void Exception::raise() const
+{
+ Exception e = *this;
+ throw e;
+}
+
+Exception *Exception::clone() const
+{
+ return new Exception(*this);
+}
+
+void UnhandledException::raise() const
+{
+ UnhandledException e = *this;
+ throw e;
+}
+
+Exception *UnhandledException::clone() const
+{
+ return new UnhandledException(*this);
+}
+
+#ifndef qdoc
+
+namespace internal {
+
+class Base
+{
+public:
+ Base(Exception *exception)
+ : exception(exception), refCount(1), hasThrown(false) { }
+ ~Base() { delete exception; }
+
+ Exception *exception;
+ QAtomicInt refCount;
+ bool hasThrown;
+};
+
+ExceptionHolder::ExceptionHolder(Exception *exception)
+: base(new Base(exception)) {}
+
+ExceptionHolder::ExceptionHolder(const ExceptionHolder &other)
+: base(other.base)
+{
+ base->refCount.ref();
+}
+
+void ExceptionHolder::operator=(const ExceptionHolder &other)
+{
+ if (base == other.base)
+ return;
+
+ if (base->refCount.deref() == false)
+ delete base;
+
+ base = other.base;
+ base->refCount.ref();
+}
+
+ExceptionHolder::~ExceptionHolder()
+{
+ if (base->refCount.deref() == 0)
+ delete base;
+}
+
+Exception *ExceptionHolder::exception() const
+{
+ return base->exception;
+}
+
+void ExceptionStore::setException(const Exception &e)
+{
+ if (hasException() == false)
+ exceptionHolder = ExceptionHolder(e.clone());
+}
+
+bool ExceptionStore::hasException() const
+{
+ return (exceptionHolder.exception() != 0);
+}
+
+ExceptionHolder ExceptionStore::exception()
+{
+ return exceptionHolder;
+}
+
+void ExceptionStore::throwPossibleException()
+{
+ if (hasException() ) {
+ exceptionHolder.base->hasThrown = true;
+ exceptionHolder.exception()->raise();
+ }
+}
+
+bool ExceptionStore::hasThrown() const { return exceptionHolder.base->hasThrown; }
+
+} // namespace internal
+
+#endif //qdoc
+
+} // namespace QtConcurrent
+
+QT_END_NAMESPACE
+
+#endif // QT_NO_EXCEPTIONS
+#endif // QT_NO_CONCURRENT