kwin/autotests/test_x11_timestamp_update.cpp
Martin Gräßlin 0bec9ad733 Improve the x11 timestamp handling
Summary:
So far KWin only updated the x11 timestamp if the new timestamp is larger
than the existing one. While this is a useful thing it creates problems
when the 32 bit msec based time stamp wraps around which happens after
running an X server for 49 days. After the timestamp wrapped around KWin
would not update the timestamp any more and thus some calls might fail.
Most prominent victims are keyboard and pointer grab which fails as the
timestamp is either larger than the server timestamp or smaller than the
last grab timestamp.

Another problem related to timestamp handling is KWin getting broken by
wrong timestamps sent by applications. A prominent example is clusterssh
which used to send a timestamp as unix time which is larger than the
x timestamp and thus our timestamp gets too large.

This change addresses these problems by allowing to reset the timestamp.
This is only used from updateXTime (which is normally invoked before we
do things like grabKeyboard). Thus we make QX11Info::getTimestamp the
ultimate trusted source for timestamps.

BUG: 377901
BUG: 348569
FIXED-IN: 5.8.7

Test Plan: As I cannot wait 50 days: unit tests for the two conditions added.

Reviewers: #kwin, #plasma

Subscribers: plasma-devel, kwin

Tags: #kwin

Differential Revision: https://phabricator.kde.org/D5704
2017-05-03 21:36:34 +02:00

123 lines
3.4 KiB
C++

/********************************************************************
KWin - the KDE window manager
This file is part of the KDE project.
Copyright (C) 2017 Martin Gräßlin <mgraesslin@kde.org>
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*********************************************************************/
#include <QTest>
#include <QX11Info>
#include "main.h"
#include "utils.h"
namespace KWin
{
class X11TestApplication : public Application
{
Q_OBJECT
public:
X11TestApplication(int &argc, char **argv);
virtual ~X11TestApplication();
protected:
void performStartup() override;
};
X11TestApplication::X11TestApplication(int &argc, char **argv)
: Application(OperationModeX11, argc, argv)
{
setX11Connection(QX11Info::connection());
setX11RootWindow(QX11Info::appRootWindow());
}
X11TestApplication::~X11TestApplication()
{
}
void X11TestApplication::performStartup()
{
}
}
class X11TimestampUpdateTest : public QObject
{
Q_OBJECT
private Q_SLOTS:
void testGrabAfterServerTime();
void testBeforeLastGrabTime();
};
void X11TimestampUpdateTest::testGrabAfterServerTime()
{
// this test tries to grab the X keyboard with a timestamp in future
// that should fail, but after updating the X11 timestamp, it should
// work again
KWin::updateXTime();
QCOMPARE(KWin::grabXKeyboard(), true);
KWin::ungrabXKeyboard();
// now let's change the timestamp
KWin::kwinApp()->setX11Time(KWin::xTime() + 5 * 60 * 1000);
// now grab keyboard should fail
QCOMPARE(KWin::grabXKeyboard(), false);
// let's update timestamp, now it should work again
KWin::updateXTime();
QCOMPARE(KWin::grabXKeyboard(), true);
KWin::ungrabXKeyboard();
}
void X11TimestampUpdateTest::testBeforeLastGrabTime()
{
// this test tries to grab the X keyboard with a timestamp before the
// last grab time on the server. That should fail, but after updating the X11
// timestamp it should work again
// first set the grab timestamp
KWin::updateXTime();
QCOMPARE(KWin::grabXKeyboard(), true);
KWin::ungrabXKeyboard();
// now go to past
const auto timestamp = KWin::xTime();
KWin::kwinApp()->setX11Time(KWin::xTime() - 5 * 60 * 1000, KWin::Application::TimestampUpdate::Always);
QCOMPARE(KWin::xTime(), timestamp - 5 * 60 * 1000);
// now grab keyboard should fail
QCOMPARE(KWin::grabXKeyboard(), false);
// let's update timestamp, now it should work again
KWin::updateXTime();
QVERIFY(KWin::xTime() >= timestamp);
QCOMPARE(KWin::grabXKeyboard(), true);
KWin::ungrabXKeyboard();
}
int main(int argc, char *argv[])
{
setenv("QT_QPA_PLATFORM", "xcb", true);
KWin::X11TestApplication app(argc, argv);
app.setAttribute(Qt::AA_Use96Dpi, true);
X11TimestampUpdateTest tc;
return QTest::qExec(&tc, argc, argv);
}
#include "test_x11_timestamp_update.moc"