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-rw-r--r--src/corelib/kernel/qelapsedtimer.cpp69
1 files changed, 29 insertions, 40 deletions
diff --git a/src/corelib/kernel/qelapsedtimer.cpp b/src/corelib/kernel/qelapsedtimer.cpp
index 6d9800fd33..230bcac33f 100644
--- a/src/corelib/kernel/qelapsedtimer.cpp
+++ b/src/corelib/kernel/qelapsedtimer.cpp
@@ -1,12 +1,11 @@
/****************************************************************************
**
-** Copyright (C) 2021 The Qt Company Ltd.
+** Copyright (C) 2016 The Qt Company Ltd.
** Contact: https://www.qt.io/licensing/
**
** This file is part of the QtCore module of the Qt Toolkit.
**
-** $QT_BEGIN_LICENSE:COMM$
-**
+** $QT_BEGIN_LICENSE:LGPL$
** Commercial License Usage
** Licensees holding valid commercial Qt licenses may use this file in
** accordance with the commercial license agreement provided with the
@@ -15,25 +14,26 @@
** and conditions see https://www.qt.io/terms-conditions. For further
** information use the contact form at https://www.qt.io/contact-us.
**
-** $QT_END_LICENSE$
-**
-**
-**
-**
-**
-**
-**
-**
-**
-**
-**
-**
-**
-**
-**
-**
-**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
**
+** $QT_END_LICENSE$
**
****************************************************************************/
@@ -111,18 +111,6 @@ QT_BEGIN_NAMESPACE
that the clock used is the same as QElapsedTimer (see
QElapsedTimer::clockType()).
- \section2 32-bit overflows
-
- Some of the clocks used by QElapsedTimer have a limited range and may
- overflow after hitting the upper limit (usually 32-bit). QElapsedTimer
- deals with this overflow issue and presents a consistent timing. However,
- when extracting the time since reference from QElapsedTimer, two
- different processes in the same machine may have different understanding
- of how much time has actually elapsed.
-
- The information on which clocks types may overflow and how to remedy that
- issue is documented along with the clock types.
-
\sa QTime, QTimer, QDeadlineTimer
*/
@@ -138,10 +126,13 @@ QT_BEGIN_NAMESPACE
used.
\value SystemTime The human-readable system time. This clock is not monotonic.
- \value MonotonicClock The system's monotonic clock, usually found in Unix systems. This clock is monotonic and does not overflow.
+ \value MonotonicClock The system's monotonic clock, usually found in Unix systems.
+ This clock is monotonic.
\value TickCounter Not used anymore.
- \value MachAbsoluteTime The Mach kernel's absolute time (\macos and iOS). This clock is monotonic and does not overflow.
- \value PerformanceCounter The performance counter provided by Windows. This clock is monotonic and does not overflow.
+ \value MachAbsoluteTime The Mach kernel's absolute time (\macos and iOS).
+ This clock is monotonic.
+ \value PerformanceCounter The performance counter provided by Windows.
+ This clock is monotonic.
\section2 SystemTime
@@ -159,8 +150,6 @@ QT_BEGIN_NAMESPACE
arbitrary point in the past. This clock type is used on Unix systems
which support POSIX monotonic clocks (\tt{_POSIX_MONOTONIC_CLOCK}).
- This clock does not overflow.
-
\section2 MachAbsoluteTime
This clock type is based on the absolute time presented by Mach kernels,
@@ -169,14 +158,14 @@ QT_BEGIN_NAMESPACE
a POSIX monotonic clock with values differing from the Mach absolute
time.
- This clock is monotonic and does not overflow.
+ This clock is monotonic.
\section2 PerformanceCounter
This clock uses the Windows functions \tt{QueryPerformanceCounter} and
\tt{QueryPerformanceFrequency} to access the system's performance counter.
- This clock is monotonic and does not overflow.
+ This clock is monotonic.
\sa clockType(), isMonotonic()
*/