kwin/main_wayland.cpp
Martin Gräßlin 6bf44b7db4 [wayland] Add an X11 output backend
This new backend allows to start a kwin_wayland server nested on an
X-Server by using a normal X11 window as output. This allows testing
kwin_wayland without needing to start another Wayland server first.

The behavior is triggered by using new command line arguments:
--windowed
--x11-display=<:0>

With optional --width and --height arguments.

In this mode the WaylandBackend is not created at all.

So far the backend is not fully integrated yet and only the QPainter
backend supports this mode.
2015-03-20 14:08:53 +01:00

410 lines
15 KiB
C++

/********************************************************************
KWin - the KDE window manager
This file is part of the KDE project.
Copyright (C) 2014 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 "main_wayland.h"
#include "workspace.h"
#include <config-kwin.h>
// kwin
#include "wayland_backend.h"
#include "wayland_server.h"
#include "xcbutils.h"
#include "x11windowed_backend.h"
// KWayland
#include <KWayland/Server/display.h>
#include <KWayland/Server/seat_interface.h>
// KDE
#include <KLocalizedString>
// Qt
#include <qplatformdefs.h>
#include <QCommandLineParser>
#include <QtConcurrentRun>
#include <QFile>
#include <QFutureWatcher>
#include <QtCore/private/qeventdispatcher_unix_p.h>
#include <QSocketNotifier>
#include <QThread>
#include <QDebug>
#include <QWindow>
// system
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif // HAVE_UNISTD_H
#include <iostream>
namespace KWin
{
static void sighandler(int)
{
QApplication::exit();
}
static int startXServer(int waylandSocket, int wmFd);
static void readDisplay(int pipe);
//************************************
// ApplicationWayland
//************************************
ApplicationWayland::ApplicationWayland(int &argc, char **argv)
: Application(OperationModeWaylandAndX11, argc, argv)
{
}
ApplicationWayland::~ApplicationWayland()
{
destroyWorkspace();
delete Wayland::WaylandBackend::self();
if (x11Connection()) {
Xcb::setInputFocus(XCB_INPUT_FOCUS_POINTER_ROOT);
xcb_disconnect(x11Connection());
}
}
void ApplicationWayland::performStartup()
{
setOperationMode(m_startXWayland ? OperationModeXwayland : OperationModeWaylandAndX11);
// first load options - done internally by a different thread
createOptions();
// try creating the Wayland Backend
createInput();
if (!X11WindowedBackend::self()) {
// only create WaylandBackend if we do not use X11WindowedBackend
Wayland::WaylandBackend *backend = Wayland::WaylandBackend::create();
connect(backend, &Wayland::WaylandBackend::connectionFailed, this,
[] () {
fputs(i18n("kwin_wayland: could not connect to Wayland Server, ensure WAYLAND_DISPLAY is set.\n").toLocal8Bit().constData(), stderr);
::exit(1);
}
);
connect(backend, &Wayland::WaylandBackend::outputsChanged, this, &ApplicationWayland::continueStartupWithScreens);
} else {
continueStartupWithScreens();
}
}
void ApplicationWayland::continueStartupWithScreens()
{
if (Wayland::WaylandBackend::self()) {
disconnect(Wayland::WaylandBackend::self(), &Wayland::WaylandBackend::outputsChanged, this, &ApplicationWayland::continueStartupWithScreens);
}
createScreens();
waylandServer()->initOutputs();
if (!m_startXWayland) {
continueStartupWithX();
return;
}
createCompositor();
int sx[2];
if (socketpair(AF_UNIX, SOCK_STREAM | SOCK_CLOEXEC, 0, sx) < 0) {
std::cerr << "FATAL ERROR: failed to open socket to open XCB connection" << std::endl;
exit(1);
return;
}
const int fd = waylandServer()->createXWaylandConnection();
if (fd == -1) {
std::cerr << "FATAL ERROR: failed to open socket for Xwayland" << std::endl;
exit(1);
return;
}
m_xcbConnectionFd = sx[0];
const int xDisplayPipe = startXServer(fd, sx[1]);
QFutureWatcher<void> *watcher = new QFutureWatcher<void>(this);
QObject::connect(watcher, &QFutureWatcher<void>::finished, this, &ApplicationWayland::continueStartupWithX, Qt::QueuedConnection);
QObject::connect(watcher, &QFutureWatcher<void>::finished, watcher, &QFutureWatcher<void>::deleteLater, Qt::QueuedConnection);
watcher->setFuture(QtConcurrent::run(readDisplay, xDisplayPipe));
}
void ApplicationWayland::continueStartupWithX()
{
createX11Connection();
xcb_connection_t *c = x11Connection();
if (!c) {
// about to quit
return;
}
QSocketNotifier *notifier = new QSocketNotifier(xcb_get_file_descriptor(c), QSocketNotifier::Read, this);
auto processXcbEvents = [this, c] {
while (auto event = xcb_poll_for_event(c)) {
updateX11Time(event);
if (Workspace::self()) {
Workspace::self()->workspaceEvent(event);
}
free(event);
}
xcb_flush(c);
};
connect(notifier, &QSocketNotifier::activated, this, processXcbEvents);
connect(QThread::currentThread()->eventDispatcher(), &QAbstractEventDispatcher::aboutToBlock, this, processXcbEvents);
connect(QThread::currentThread()->eventDispatcher(), &QAbstractEventDispatcher::awake, this, processXcbEvents);
// create selection owner for WM_S0 - magic X display number expected by XWayland
KSelectionOwner owner("WM_S0", c, x11RootWindow());
owner.claim(true);
createAtoms();
setupEventFilters();
// Check whether another windowmanager is running
const uint32_t maskValues[] = {XCB_EVENT_MASK_SUBSTRUCTURE_REDIRECT};
ScopedCPointer<xcb_generic_error_t> redirectCheck(xcb_request_check(connection(),
xcb_change_window_attributes_checked(connection(),
rootWindow(),
XCB_CW_EVENT_MASK,
maskValues)));
if (!redirectCheck.isNull()) {
fputs(i18n("kwin_wayland: an X11 window manager is running on the X11 Display.\n").toLocal8Bit().constData(), stderr);
::exit(1);
}
// HACK: create a QWindow in a thread to force QtWayland to create the client buffer integration
// this performs an eglInitialize which would block as it does a roundtrip to the Wayland server
// in the main thread. By moving into a thread we get the initialize without hitting the problem
// This needs to be done before creating the Workspace as from inside Workspace the dangerous code
// gets hit in the main thread
QFutureWatcher<void> *eglInitWatcher = new QFutureWatcher<void>(this);
connect(eglInitWatcher, &QFutureWatcher<void>::finished, this,
[this, eglInitWatcher] {
eglInitWatcher->deleteLater();
createWorkspace();
Xcb::sync(); // Trigger possible errors, there's still a chance to abort
notifyKSplash();
}
);
eglInitWatcher->setFuture(QtConcurrent::run([] {
QWindow w;
w.setSurfaceType(QSurface::RasterGLSurface);
w.create();
}));
}
void ApplicationWayland::createX11Connection()
{
int screenNumber = 0;
xcb_connection_t *c = nullptr;
if (m_xcbConnectionFd == -1) {
c = xcb_connect(nullptr, &screenNumber);
} else {
c = xcb_connect_to_fd(m_xcbConnectionFd, nullptr);
}
if (int error = xcb_connection_has_error(c)) {
std::cerr << "FATAL ERROR: Creating connection to XServer failed: " << error << std::endl;
exit(1);
return;
}
setX11Connection(c);
// we don't support X11 multi-head in Wayland
setX11ScreenNumber(screenNumber);
setX11RootWindow(defaultScreen()->root);
}
/**
* Starts the Xwayland-Server.
* The new process is started by forking into it.
**/
static int startXServer(int waylandSocket, int wmFd)
{
int pipeFds[2];
if (pipe(pipeFds) != 0) {
std::cerr << "FATAL ERROR failed to create pipe to start Xwayland " << std::endl;
exit(1);
}
pid_t pid = fork();
if (pid == 0) {
// child process - should be turned into X-Server
// writes to pipe, closes read side
close(pipeFds[0]);
char fdbuf[16];
sprintf(fdbuf, "%d", pipeFds[1]);
char wmfdbuf[16];
int fd = dup(wmFd);
if (fd < 0) {
std::cerr << "FATAL ERROR: failed to open socket to open XCB connection" << std::endl;
exit(20);
return -1;
}
sprintf(wmfdbuf, "%d", fd);
int wlfd = dup(waylandSocket);
if (wlfd < 0) {
std::cerr << "FATAL ERROR: failed to open socket for Xwayland" << std::endl;
exit(20);
return -1;
}
qputenv("WAYLAND_SOCKET", QByteArray::number(wlfd));
execlp("Xwayland", "Xwayland", "-displayfd", fdbuf, "-rootless", "-wm", wmfdbuf, (char *)0);
close(pipeFds[1]);
exit(20);
}
// parent process - this is KWin
// reads from pipe, closes write side
close(pipeFds[1]);
return pipeFds[0];
}
static void readDisplay(int pipe)
{
QFile readPipe;
if (!readPipe.open(pipe, QIODevice::ReadOnly)) {
std::cerr << "FATAL ERROR failed to open pipe to start X Server" << std::endl;
exit(1);
}
QByteArray displayNumber = readPipe.readLine();
displayNumber.prepend(QByteArray(":"));
displayNumber.remove(displayNumber.size() -1, 1);
std::cout << "X-Server started on display " << displayNumber.constData() << std::endl;
setenv("DISPLAY", displayNumber.constData(), true);
// close our pipe
close(pipe);
}
} // namespace
extern "C"
KWIN_EXPORT int kdemain(int argc, char * argv[])
{
// process command line arguments to figure out whether we have to start Xwayland and the Wayland socket
QByteArray waylandSocket;
for (int i = 1; i < argc; ++i) {
QByteArray arg = QByteArray::fromRawData(argv[i], qstrlen(argv[i]));
if (arg == "--socket" || arg == "-s") {
if (++i < argc) {
waylandSocket = QByteArray::fromRawData(argv[i], qstrlen(argv[i]));
}
continue;
}
if (arg.startsWith("--socket=")) {
waylandSocket = arg.mid(9);
}
}
// set our own event dispatcher to be able to dispatch events before the event loop is started
QAbstractEventDispatcher *eventDispatcher = new QEventDispatcherUNIX();
QCoreApplication::setEventDispatcher(eventDispatcher);
KWin::WaylandServer *server = KWin::WaylandServer::create(nullptr);
server->init(waylandSocket);
KWin::Application::setupMalloc();
KWin::Application::setupLocalizedString();
KWin::Application::setupLoggingCategoryFilters();
if (signal(SIGTERM, KWin::sighandler) == SIG_IGN)
signal(SIGTERM, SIG_IGN);
if (signal(SIGINT, KWin::sighandler) == SIG_IGN)
signal(SIGINT, SIG_IGN);
if (signal(SIGHUP, KWin::sighandler) == SIG_IGN)
signal(SIGHUP, SIG_IGN);
// enforce wayland plugin, unfortunately command line switch has precedence
setenv("QT_QPA_PLATFORM", "wayland", true);
#if (QT_VERSION < QT_VERSION_CHECK(5, 4, 2))
// TODO: remove warning once we depend on Qt 5.5
qWarning() << "QtWayland 5.4.2 required, application might freeze if not present!";
#endif
qputenv("WAYLAND_SOCKET", QByteArray::number(server->createQtConnection()));
KWin::ApplicationWayland a(argc, argv);
a.setupTranslator();
server->setParent(&a);
KWin::Application::createAboutData();
QCommandLineOption xwaylandOption(QStringLiteral("xwayland"),
i18n("Start a rootless Xwayland server."));
QCommandLineOption waylandSocketOption(QStringList{QStringLiteral("s"), QStringLiteral("socket")},
i18n("Name of the Wayland socket to listen on. If not set \"wayland-0\" is used."),
QStringLiteral("socket"));
QCommandLineOption windowedOption(QStringLiteral("windowed"),
i18n("Use a nested compositor in windowed mode."));
QCommandLineOption x11DisplayOption(QStringLiteral("x11-display"),
i18n("The X11 Display to use in windowed mode on platform X11."),
QStringLiteral("display"));
QCommandLineOption widthOption(QStringLiteral("width"),
i18n("The width for windowed mode. Default width is 1024."),
QStringLiteral("width"));
widthOption.setDefaultValue(QString::number(1024));
QCommandLineOption heightOption(QStringLiteral("height"),
i18n("The height for windowed mode. Default height is 768."),
QStringLiteral("height"));
heightOption.setDefaultValue(QString::number(768));
QCommandLineParser parser;
a.setupCommandLine(&parser);
parser.addOption(xwaylandOption);
parser.addOption(waylandSocketOption);
parser.addOption(windowedOption);
parser.addOption(x11DisplayOption);
parser.addOption(widthOption);
parser.addOption(heightOption);
#if HAVE_INPUT
QCommandLineOption libinputOption(QStringLiteral("libinput"),
i18n("Enable libinput support for input events processing. Note: never use in a nested session."));
parser.addOption(libinputOption);
#endif
parser.process(a);
a.processCommandLine(&parser);
#if HAVE_INPUT
KWin::Application::setUseLibinput(parser.isSet(libinputOption));
#endif
if (parser.isSet(windowedOption)) {
bool ok = false;
const int width = parser.value(widthOption).toInt(&ok);
if (!ok) {
std::cerr << "FATAL ERROR incorrect value for width" << std::endl;
return 1;
}
const int height = parser.value(heightOption).toInt(&ok);
if (!ok) {
std::cerr << "FATAL ERROR incorrect value for height" << std::endl;
return 1;
}
KWin::X11WindowedBackend *x11Backend = KWin::X11WindowedBackend::create(parser.value(x11DisplayOption), QSize(width, height), &a);
if (!x11Backend->isValid()) {
std::cerr << "FATAL ERROR failed to connet to X Server" << std::endl;
return 1;
}
server->seat()->setHasPointer(true);
server->seat()->setHasKeyboard(true);
}
a.setStartXwayland(parser.isSet(xwaylandOption));
a.start();
return a.exec();
}