kwin/screens.cpp
Martin Gräßlin 44e37aacdf Set initial count of screens before calling Screens::init
Screens::init sets up a Qt::QueuedConnection connect from countChanged
to changed. This means that when first setting up the connection a
changed signal will be delivered in the next event cycle. This can mess
with other code. E.g. WaylandServer recreating outputs which can make
Xwayland crash or KWin internally crash.

To solve this problem we just need to make sure to set the output count
to the initial value before performing the init.

Reviewed-By: bshah
2016-08-05 09:59:22 +02:00

243 lines
5.8 KiB
C++

/********************************************************************
KWin - the KDE window manager
This file is part of the KDE project.
Copyright (C) 2013 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 "screens.h"
#include <abstract_client.h>
#include <client.h>
#include "cursor.h"
#include "utils.h"
#include "settings.h"
#include <workspace.h>
#include <config-kwin.h>
#include "platform.h"
#include "wayland_server.h"
#ifdef KWIN_UNIT_TEST
#include <mock_screens.h>
#endif
namespace KWin
{
Screens *Screens::s_self = nullptr;
Screens *Screens::create(QObject *parent)
{
Q_ASSERT(!s_self);
#ifdef KWIN_UNIT_TEST
s_self = new MockScreens(parent);
#else
s_self = kwinApp()->platform()->createScreens(parent);
#endif
Q_ASSERT(s_self);
s_self->init();
return s_self;
}
Screens::Screens(QObject *parent)
: QObject(parent)
, m_count(0)
, m_current(0)
, m_currentFollowsMouse(false)
, m_changedTimer(new QTimer(this))
{
}
Screens::~Screens()
{
s_self = NULL;
}
void Screens::init()
{
m_changedTimer->setSingleShot(true);
m_changedTimer->setInterval(100);
connect(m_changedTimer, SIGNAL(timeout()), SLOT(updateCount()));
connect(m_changedTimer, SIGNAL(timeout()), SIGNAL(changed()));
connect(this, &Screens::countChanged, this, &Screens::changed, Qt::QueuedConnection);
connect(this, &Screens::changed, this, &Screens::updateSize);
connect(this, &Screens::sizeChanged, this, &Screens::geometryChanged);
Settings settings;
settings.setDefaults();
m_currentFollowsMouse = settings.activeMouseScreen();
}
QString Screens::name(int screen) const
{
Q_UNUSED(screen)
qCWarning(KWIN_CORE, "%s::name(int screen) is a stub, please reimplement it!", metaObject()->className());
return QLatin1String("DUMMY");
}
float Screens::refreshRate(int screen) const
{
Q_UNUSED(screen)
qCWarning(KWIN_CORE, "%s::refreshRate(int screen) is a stub, please reimplement it!", metaObject()->className());
return 60.0f;
}
void Screens::reconfigure()
{
if (!m_config) {
return;
}
Settings settings(m_config);
settings.read();
setCurrentFollowsMouse(settings.activeMouseScreen());
}
void Screens::updateSize()
{
QRect bounding;
for (int i = 0; i < count(); ++i) {
bounding = bounding.united(geometry(i));
}
if (m_boundingSize != bounding.size()) {
m_boundingSize = bounding.size();
emit sizeChanged();
}
}
void Screens::setCount(int count)
{
if (m_count == count) {
return;
}
const int previous = m_count;
m_count = count;
emit countChanged(previous, count);
}
void Screens::setCurrent(int current)
{
if (m_current == current) {
return;
}
m_current = current;
emit currentChanged();
}
void Screens::setCurrent(const QPoint &pos)
{
setCurrent(number(pos));
}
void Screens::setCurrent(const AbstractClient *c)
{
if (!c->isActive()) {
return;
}
if (!c->isOnScreen(m_current)) {
setCurrent(c->screen());
}
}
void Screens::setCurrentFollowsMouse(bool follows)
{
if (m_currentFollowsMouse == follows) {
return;
}
m_currentFollowsMouse = follows;
}
int Screens::current() const
{
if (m_currentFollowsMouse) {
return number(Cursor::pos());
}
AbstractClient *client = Workspace::self()->activeClient();
if (client && !client->isOnScreen(m_current)) {
return client->screen();
}
return m_current;
}
int Screens::intersecting(const QRect &r) const
{
int cnt = 0;
for (int i = 0; i < count(); ++i) {
if (geometry(i).intersects(r)) {
++cnt;
}
}
return cnt;
}
BasicScreens::BasicScreens(Platform *backend, QObject *parent)
: Screens(parent)
, m_backend(backend)
{
}
BasicScreens::~BasicScreens() = default;
void BasicScreens::init()
{
updateCount();
KWin::Screens::init();
#ifndef KWIN_UNIT_TEST
connect(m_backend, &Platform::screenSizeChanged,
this, &BasicScreens::startChangedTimer);
#endif
emit changed();
}
QRect BasicScreens::geometry(int screen) const
{
if (screen < m_geometries.count()) {
return m_geometries.at(screen);
}
return QRect();
}
QSize BasicScreens::size(int screen) const
{
if (screen < m_geometries.count()) {
return m_geometries.at(screen).size();
}
return QSize();
}
void BasicScreens::updateCount()
{
m_geometries = m_backend->screenGeometries();
setCount(m_geometries.count());
}
int BasicScreens::number(const QPoint &pos) const
{
int bestScreen = 0;
int minDistance = INT_MAX;
for (int i = 0; i < m_geometries.count(); ++i) {
const QRect &geo = m_geometries.at(i);
if (geo.contains(pos)) {
return i;
}
int distance = QPoint(geo.topLeft() - pos).manhattanLength();
distance = qMin(distance, QPoint(geo.topRight() - pos).manhattanLength());
distance = qMin(distance, QPoint(geo.bottomRight() - pos).manhattanLength());
distance = qMin(distance, QPoint(geo.bottomLeft() - pos).manhattanLength());
if (distance < minDistance) {
minDistance = distance;
bestScreen = i;
}
}
return bestScreen;
}
} // namespace