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-rw-r--r--src/corelib/kernel/qcoreevent.cpp134
1 files changed, 84 insertions, 50 deletions
diff --git a/src/corelib/kernel/qcoreevent.cpp b/src/corelib/kernel/qcoreevent.cpp
index edf262b8af..191ceaa37b 100644
--- a/src/corelib/kernel/qcoreevent.cpp
+++ b/src/corelib/kernel/qcoreevent.cpp
@@ -1,40 +1,32 @@
/****************************************************************************
**
-** Copyright (C) 2013 Digia Plc and/or its subsidiary(-ies).
+** Copyright (C) 2014 Digia Plc and/or its subsidiary(-ies).
** Contact: http://www.qt-project.org/legal
**
** This file is part of the QtCore module of the Qt Toolkit.
**
-** $QT_BEGIN_LICENSE:LGPL$
+** $QT_BEGIN_LICENSE:LGPL21$
** Commercial License Usage
** Licensees holding valid commercial Qt licenses may use this file in
** accordance with the commercial license agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
-** a written agreement between you and Digia. For licensing terms and
-** conditions see http://qt.digia.com/licensing. For further information
+** a written agreement between you and Digia. For licensing terms and
+** conditions see http://qt.digia.com/licensing. For further information
** use the contact form at http://qt.digia.com/contact-us.
**
** 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.
+** General Public License version 2.1 or version 3 as published by the Free
+** Software Foundation and appearing in the file LICENSE.LGPLv21 and
+** LICENSE.LGPLv3 included in the packaging of this file. Please review the
+** following information to ensure the GNU Lesser General Public License
+** requirements will be met: https://www.gnu.org/licenses/lgpl.html and
+** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
**
** In addition, as a special exception, Digia gives you certain additional
-** rights. These rights are described in the Digia Qt LGPL Exception
+** rights. These rights are described in the Digia 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.
-**
-**
** $QT_END_LICENSE$
**
****************************************************************************/
@@ -43,8 +35,9 @@
#include "qcoreapplication.h"
#include "qcoreapplication_p.h"
-#include "qmutex.h"
-#include "qset.h"
+#include "qbasicatomic.h"
+
+#include <limits>
QT_BEGIN_NAMESPACE
@@ -183,6 +176,7 @@ QT_BEGIN_NAMESPACE
\value MouseMove Mouse move (QMouseEvent).
\value MouseTrackingChange The mouse tracking state has changed.
\value Move Widget's position changed (QMoveEvent).
+ \value NativeGesture The system has detected a gesture (QNativeGestureEvent).
\value OrientationChange The screens orientation has changes (QScreenOrientationChangeEvent)
\value Paint Screen update necessary (QPaintEvent).
\value PaletteChange Palette of the widget changed.
@@ -192,6 +186,7 @@ QT_BEGIN_NAMESPACE
\value Polish The widget is polished.
\value PolishRequest The widget should be polished.
\value QueryWhatsThis The widget should accept the event if it has "What's This?" help.
+ \value ReadOnlyChange Widget's read-only state has changed (since Qt 5.4).
\value RequestSoftwareInputPanel A widget wants to open a software input panel (SIP).
\value Resize Widget's size changed (QResizeEvent).
\value ScrollPrepare The object needs to fill in its geometry information (QScrollPrepareEvent).
@@ -275,6 +270,7 @@ QT_BEGIN_NAMESPACE
\omitvalue FutureCallOut
\omitvalue NativeGesture
\omitvalue WindowChangeInternal
+ \omitvalue ScreenChangeInternal
*/
/*!
@@ -389,13 +385,71 @@ QEvent::~QEvent()
The return value of this function is not defined for paint events.
*/
-class QEventUserEventRegistration
-{
-public:
- QMutex mutex;
- QSet<int> set;
+namespace {
+template <size_t N>
+struct QBasicAtomicBitField {
+ enum {
+ BitsPerInt = std::numeric_limits<uint>::digits,
+ NumInts = (N + BitsPerInt - 1) / BitsPerInt,
+ NumBits = N
+ };
+
+ // This atomic int points to the next (possibly) free ID saving
+ // the otherwise necessary scan through 'data':
+ QBasicAtomicInteger<uint> next;
+ QBasicAtomicInteger<uint> data[NumInts];
+
+ bool allocateSpecific(int which) Q_DECL_NOTHROW
+ {
+ QBasicAtomicInteger<uint> &entry = data[which / BitsPerInt];
+ const uint old = entry.load();
+ const uint bit = 1U << (which % BitsPerInt);
+ return !(old & bit) // wasn't taken
+ && entry.testAndSetRelaxed(old, old | bit); // still wasn't taken
+
+ // don't update 'next' here - it's unlikely that it will need
+ // to be updated, in the general case, and having 'next'
+ // trailing a bit is not a problem, as it is just a starting
+ // hint for allocateNext(), which, when wrong, will just
+ // result in a few more rounds through the allocateNext()
+ // loop.
+ }
+
+ int allocateNext() Q_DECL_NOTHROW
+ {
+ // Unroll loop to iterate over ints, then bits? Would save
+ // potentially a lot of cmpxchgs, because we can scan the
+ // whole int before having to load it again.
+
+ // Then again, this should never execute many iterations, so
+ // leave like this for now:
+ for (uint i = next.load(); i < NumBits; ++i) {
+ if (allocateSpecific(i)) {
+ // remember next (possibly) free id:
+ const uint oldNext = next.load();
+ next.testAndSetRelaxed(oldNext, qMax(i + 1, oldNext));
+ return i;
+ }
+ }
+ return -1;
+ }
};
-Q_GLOBAL_STATIC(QEventUserEventRegistration, userEventRegistrationHelper)
+
+} // unnamed namespace
+
+typedef QBasicAtomicBitField<QEvent::MaxUser - QEvent::User + 1> UserEventTypeRegistry;
+
+static UserEventTypeRegistry userEventTypeRegistry;
+
+static inline int registerEventTypeZeroBased(int id) Q_DECL_NOTHROW
+{
+ // if the type hint hasn't been registered yet, take it:
+ if (id < UserEventTypeRegistry::NumBits && id >= 0 && userEventTypeRegistry.allocateSpecific(id))
+ return id;
+
+ // otherwise, ignore hint:
+ return userEventTypeRegistry.allocateNext();
+}
/*!
\since 4.4
@@ -410,30 +464,10 @@ Q_GLOBAL_STATIC(QEventUserEventRegistration, userEventRegistrationHelper)
Returns -1 if all available values are already taken or the
program is shutting down.
*/
-int QEvent::registerEventType(int hint)
+int QEvent::registerEventType(int hint) Q_DECL_NOTHROW
{
- QEventUserEventRegistration *userEventRegistration
- = userEventRegistrationHelper();
- if (!userEventRegistration)
- return -1;
-
- QMutexLocker locker(&userEventRegistration->mutex);
-
- // if the type hint hasn't been registered yet, take it
- if (hint >= QEvent::User && hint <= QEvent::MaxUser && !userEventRegistration->set.contains(hint)) {
- userEventRegistration->set.insert(hint);
- return hint;
- }
-
- // find a free event type, starting at MaxUser and decreasing
- int id = QEvent::MaxUser;
- while (userEventRegistration->set.contains(id) && id >= QEvent::User)
- --id;
- if (id >= QEvent::User) {
- userEventRegistration->set.insert(id);
- return id;
- }
- return -1;
+ const int result = registerEventTypeZeroBased(QEvent::MaxUser - hint);
+ return result < 0 ? -1 : QEvent::MaxUser - result ;
}
/*!
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