kwin/main_wayland.cpp
Vlad Zahorodnii b13a74c908 xwayland: Replace criticalError() signal with a less fatal signal
If the Xwayland executable can't be found, the whole session will die
because a criticalError() signal will be emitted.

This change replaces the criticalError() signal with a less severe
signal.

If the errorOccurred() signal has been emitted during the startup
sequence, kwin won't die and will just continue with spawning the
session process.
2020-09-09 15:25:59 +00:00

703 lines
24 KiB
C++

/*
KWin - the KDE window manager
This file is part of the KDE project.
SPDX-FileCopyrightText: 2014 Martin Gräßlin <mgraesslin@kde.org>
SPDX-License-Identifier: GPL-2.0-or-later
*/
#include "main_wayland.h"
#include "composite.h"
#include "virtualkeyboard.h"
#include "workspace.h"
#include <config-kwin.h>
// kwin
#include "platform.h"
#include "effects.h"
#include "tabletmodemanager.h"
#ifdef PipeWire_FOUND
#include "screencast/screencastmanager.h"
#endif
#include "wayland_server.h"
#include "xwl/xwayland.h"
// KWayland
#include <KWaylandServer/display.h>
#include <KWaylandServer/seat_interface.h>
// KDE
#include <KCrash>
#include <KLocalizedString>
#include <KPluginLoader>
#include <KPluginMetaData>
#include <KQuickAddons/QtQuickSettings>
#include <KShell>
// Qt
#include <qplatformdefs.h>
#include <QCommandLineParser>
#include <QFileInfo>
#include <QProcess>
#include <QStyle>
#include <QDebug>
#include <QWindow>
// system
#if HAVE_SYS_PRCTL_H
#include <sys/prctl.h>
#endif
#if HAVE_SYS_PROCCTL_H
#include <sys/procctl.h>
#endif
#if HAVE_LIBCAP
#include <sys/capability.h>
#endif
#include <sched.h>
#include <iostream>
#include <iomanip>
namespace KWin
{
static void sighandler(int)
{
QApplication::exit();
}
void disableDrKonqi()
{
KCrash::setDrKonqiEnabled(false);
}
// run immediately, before Q_CORE_STARTUP functions
// that would enable drkonqi
Q_CONSTRUCTOR_FUNCTION(disableDrKonqi)
enum class RealTimeFlags
{
DontReset,
ResetOnFork
};
namespace {
void gainRealTime(RealTimeFlags flags = RealTimeFlags::DontReset)
{
#if HAVE_SCHED_RESET_ON_FORK
const int minPriority = sched_get_priority_min(SCHED_RR);
struct sched_param sp;
sp.sched_priority = minPriority;
int policy = SCHED_RR;
if (flags == RealTimeFlags::ResetOnFork) {
policy |= SCHED_RESET_ON_FORK;
}
sched_setscheduler(0, policy, &sp);
#else
Q_UNUSED(flags);
#endif
}
}
//************************************
// ApplicationWayland
//************************************
ApplicationWayland::ApplicationWayland(int &argc, char **argv)
: ApplicationWaylandAbstract(OperationModeWaylandOnly, argc, argv)
{
}
ApplicationWayland::~ApplicationWayland()
{
setTerminating();
if (!waylandServer()) {
return;
}
if (auto *platform = kwinApp()->platform()) {
platform->prepareShutdown();
}
// need to unload all effects prior to destroying X connection as they might do X calls
if (effects) {
static_cast<EffectsHandlerImpl*>(effects)->unloadAllEffects();
}
delete m_xwayland;
m_xwayland = nullptr;
destroyWorkspace();
waylandServer()->dispatch();
if (QStyle *s = style()) {
s->unpolish(this);
}
waylandServer()->terminateClientConnections();
destroyCompositor();
}
void ApplicationWayland::performStartup()
{
if (m_startXWayland) {
setOperationMode(OperationModeXwayland);
}
// first load options - done internally by a different thread
createOptions();
waylandServer()->createInternalConnection();
// try creating the Wayland Backend
createInput();
// now libinput thread has been created, adjust scheduler to not leak into other processes
gainRealTime(RealTimeFlags::ResetOnFork);
VirtualKeyboard::create(this);
createBackend();
TabletModeManager::create(this);
#ifdef PipeWire_FOUND
new ScreencastManager(this);
#endif
}
void ApplicationWayland::createBackend()
{
connect(platform(), &Platform::screensQueried, this, &ApplicationWayland::continueStartupWithScreens);
connect(platform(), &Platform::initFailed, this,
[] () {
std::cerr << "FATAL ERROR: backend failed to initialize, exiting now" << std::endl;
QCoreApplication::exit(1);
}
);
platform()->init();
}
void ApplicationWayland::continueStartupWithScreens()
{
disconnect(kwinApp()->platform(), &Platform::screensQueried, this, &ApplicationWayland::continueStartupWithScreens);
createScreens();
WaylandCompositor::create();
connect(Compositor::self(), &Compositor::sceneCreated, this, &ApplicationWayland::continueStartupWithScene);
}
void ApplicationWayland::finalizeStartup()
{
if (m_xwayland) {
disconnect(m_xwayland, &Xwl::Xwayland::errorOccurred, this, &ApplicationWayland::finalizeStartup);
disconnect(m_xwayland, &Xwl::Xwayland::started, this, &ApplicationWayland::finalizeStartup);
}
startSession();
notifyStarted();
}
void ApplicationWayland::continueStartupWithScene()
{
disconnect(Compositor::self(), &Compositor::sceneCreated, this, &ApplicationWayland::continueStartupWithScene);
// Note that we start accepting client connections after creating the Workspace.
createWorkspace();
if (!waylandServer()->start()) {
qFatal("Failed to initialze the Wayland server, exiting now");
}
if (operationMode() == OperationModeWaylandOnly) {
finalizeStartup();
return;
}
m_xwayland = new Xwl::Xwayland(this);
connect(m_xwayland, &Xwl::Xwayland::errorOccurred, this, &ApplicationWayland::finalizeStartup);
connect(m_xwayland, &Xwl::Xwayland::started, this, &ApplicationWayland::finalizeStartup);
m_xwayland->start();
}
void ApplicationWayland::startSession()
{
if (!m_inputMethodServerToStart.isEmpty()) {
QStringList arguments = KShell::splitArgs(m_inputMethodServerToStart);
if (!arguments.isEmpty()) {
QString program = arguments.takeFirst();
int socket = dup(waylandServer()->createInputMethodConnection());
if (socket >= 0) {
QProcessEnvironment environment = processStartupEnvironment();
environment.insert(QStringLiteral("WAYLAND_SOCKET"), QByteArray::number(socket));
environment.insert(QStringLiteral("QT_QPA_PLATFORM"), QStringLiteral("wayland"));
environment.remove("DISPLAY");
environment.remove("WAYLAND_DISPLAY");
QProcess *p = new Process(this);
p->setProcessChannelMode(QProcess::ForwardedErrorChannel);
connect(p, qOverload<int, QProcess::ExitStatus>(&QProcess::finished), this,
[p] {
if (waylandServer()) {
waylandServer()->destroyInputMethodConnection();
}
p->deleteLater();
}
);
p->setProcessEnvironment(environment);
p->setProgram(program);
p->setArguments(arguments);
p->start();
connect(waylandServer(), &WaylandServer::terminatingInternalClientConnection, p, [p] {
p->kill();
p->waitForFinished();
});
}
} else {
qWarning("Failed to launch the input method server: %s is an invalid command",
qPrintable(m_inputMethodServerToStart));
}
}
// start session
if (!m_sessionArgument.isEmpty()) {
QStringList arguments = KShell::splitArgs(m_sessionArgument);
if (!arguments.isEmpty()) {
QString program = arguments.takeFirst();
QProcess *p = new Process(this);
p->setProcessChannelMode(QProcess::ForwardedErrorChannel);
p->setProcessEnvironment(processStartupEnvironment());
connect(p, qOverload<int, QProcess::ExitStatus>(&QProcess::finished), this, [p] (int code, QProcess::ExitStatus status) {
p->deleteLater();
if (status == QProcess::CrashExit) {
qWarning() << "Session process has crashed";
QCoreApplication::exit(-1);
return;
}
if (code) {
qWarning() << "Session process exited with code" << code;
}
QCoreApplication::exit(code);
});
p->setProgram(program);
p->setArguments(arguments);
p->start();
} else {
qWarning("Failed to launch the session process: %s is an invalid command",
qPrintable(m_sessionArgument));
}
}
// start the applications passed to us as command line arguments
if (!m_applicationsToStart.isEmpty()) {
for (const QString &application: m_applicationsToStart) {
QStringList arguments = KShell::splitArgs(application);
if (arguments.isEmpty()) {
qWarning("Failed to launch application: %s is an invalid command",
qPrintable(application));
continue;
}
QString program = arguments.takeFirst();
// note: this will kill the started process when we exit
// this is going to happen anyway as we are the wayland and X server the app connects to
QProcess *p = new Process(this);
p->setProcessChannelMode(QProcess::ForwardedErrorChannel);
p->setProcessEnvironment(processStartupEnvironment());
p->setProgram(program);
p->setArguments(arguments);
p->startDetached();
p->deleteLater();
}
}
}
static const QString s_waylandPlugin = QStringLiteral("KWinWaylandWaylandBackend");
static const QString s_x11Plugin = QStringLiteral("KWinWaylandX11Backend");
static const QString s_fbdevPlugin = QStringLiteral("KWinWaylandFbdevBackend");
#if HAVE_DRM
static const QString s_drmPlugin = QStringLiteral("KWinWaylandDrmBackend");
#endif
#if HAVE_LIBHYBRIS
static const QString s_hwcomposerPlugin = QStringLiteral("KWinWaylandHwcomposerBackend");
#endif
static const QString s_virtualPlugin = QStringLiteral("KWinWaylandVirtualBackend");
static QString automaticBackendSelection()
{
if (qEnvironmentVariableIsSet("WAYLAND_DISPLAY")) {
return s_waylandPlugin;
}
if (qEnvironmentVariableIsSet("DISPLAY")) {
return s_x11Plugin;
}
#if HAVE_LIBHYBRIS
if (qEnvironmentVariableIsSet("ANDROID_ROOT")) {
return s_hwcomposerPlugin;
}
#endif
#if HAVE_DRM
return s_drmPlugin;
#endif
return s_fbdevPlugin;
}
static void disablePtrace()
{
#if HAVE_PR_SET_DUMPABLE
// check whether we are running under a debugger
const QFileInfo parent(QStringLiteral("/proc/%1/exe").arg(getppid()));
if (parent.isSymLink() &&
(parent.symLinkTarget().endsWith(QLatin1String("/gdb")) ||
parent.symLinkTarget().endsWith(QLatin1String("/gdbserver")) ||
parent.symLinkTarget().endsWith(QLatin1String("/lldb-server")))) {
// debugger, don't adjust
return;
}
// disable ptrace in kwin_wayland
prctl(PR_SET_DUMPABLE, 0);
#endif
#if HAVE_PROC_TRACE_CTL
// FreeBSD's rudimentary procfs does not support /proc/<pid>/exe
// We could use the P_TRACED flag of the process to find out
// if the process is being debugged ond FreeBSD.
int mode = PROC_TRACE_CTL_DISABLE;
procctl(P_PID, getpid(), PROC_TRACE_CTL, &mode);
#endif
}
static void unsetDumpable(int sig)
{
#if HAVE_PR_SET_DUMPABLE
prctl(PR_SET_DUMPABLE, 1);
#endif
signal(sig, SIG_IGN);
raise(sig);
return;
}
void dropNiceCapability()
{
#if HAVE_LIBCAP
cap_t caps = cap_get_proc();
if (!caps) {
return;
}
cap_value_t capList[] = { CAP_SYS_NICE };
if (cap_set_flag(caps, CAP_PERMITTED, 1, capList, CAP_CLEAR) == -1) {
cap_free(caps);
return;
}
if (cap_set_flag(caps, CAP_EFFECTIVE, 1, capList, CAP_CLEAR) == -1) {
cap_free(caps);
return;
}
cap_set_proc(caps);
cap_free(caps);
#endif
}
} // namespace
int main(int argc, char * argv[])
{
if (getuid() == 0) {
std::cerr << "kwin_wayland does not support running as root." << std::endl;
return 1;
}
KWin::disablePtrace();
KWin::Application::setupMalloc();
KWin::Application::setupLocalizedString();
KWin::gainRealTime();
KWin::dropNiceCapability();
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);
signal(SIGABRT, KWin::unsetDumpable);
signal(SIGSEGV, KWin::unsetDumpable);
signal(SIGPIPE, SIG_IGN);
// ensure that no thread takes SIGUSR
sigset_t userSignals;
sigemptyset(&userSignals);
sigaddset(&userSignals, SIGUSR1);
sigaddset(&userSignals, SIGUSR2);
pthread_sigmask(SIG_BLOCK, &userSignals, nullptr);
QProcessEnvironment environment = QProcessEnvironment::systemEnvironment();
// enforce our internal qpa plugin, unfortunately command line switch has precedence
setenv("QT_QPA_PLATFORM", "wayland-org.kde.kwin.qpa", true);
qunsetenv("QT_DEVICE_PIXEL_RATIO");
qputenv("QT_IM_MODULE", "qtvirtualkeyboard");
qputenv("QSG_RENDER_LOOP", "basic");
QCoreApplication::setAttribute(Qt::AA_UseHighDpiPixmaps);
KWin::ApplicationWayland a(argc, argv);
a.setupTranslator();
// reset QT_QPA_PLATFORM to a sane value for any processes started from KWin
setenv("QT_QPA_PLATFORM", "wayland", true);
KWin::Application::createAboutData();
KQuickAddons::QtQuickSettings::init();
const auto availablePlugins = KPluginLoader::findPlugins(QStringLiteral("org.kde.kwin.waylandbackends"));
auto hasPlugin = [&availablePlugins] (const QString &name) {
return std::any_of(availablePlugins.begin(), availablePlugins.end(),
[name] (const KPluginMetaData &plugin) {
return plugin.pluginId() == name;
}
);
};
const bool hasSizeOption = hasPlugin(KWin::s_x11Plugin) || hasPlugin(KWin::s_virtualPlugin);
const bool hasOutputCountOption = hasPlugin(KWin::s_x11Plugin);
const bool hasX11Option = hasPlugin(KWin::s_x11Plugin);
const bool hasVirtualOption = hasPlugin(KWin::s_virtualPlugin);
const bool hasWaylandOption = hasPlugin(KWin::s_waylandPlugin);
const bool hasFramebufferOption = hasPlugin(KWin::s_fbdevPlugin);
#if HAVE_DRM
const bool hasDrmOption = hasPlugin(KWin::s_drmPlugin);
#endif
#if HAVE_LIBHYBRIS
const bool hasHwcomposerOption = hasPlugin(KWin::s_hwcomposerPlugin);
#endif
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 framebufferOption(QStringLiteral("framebuffer"),
i18n("Render to framebuffer."));
QCommandLineOption framebufferDeviceOption(QStringLiteral("fb-device"),
i18n("The framebuffer device to render to."),
QStringLiteral("fbdev"));
QCommandLineOption x11DisplayOption(QStringLiteral("x11-display"),
i18n("The X11 Display to use in windowed mode on platform X11."),
QStringLiteral("display"));
QCommandLineOption waylandDisplayOption(QStringLiteral("wayland-display"),
i18n("The Wayland Display to use in windowed mode on platform Wayland."),
QStringLiteral("display"));
QCommandLineOption virtualFbOption(QStringLiteral("virtual"), i18n("Render to a virtual framebuffer."));
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));
QCommandLineOption scaleOption(QStringLiteral("scale"),
i18n("The scale for windowed mode. Default value is 1."),
QStringLiteral("scale"));
scaleOption.setDefaultValue(QString::number(1));
QCommandLineOption outputCountOption(QStringLiteral("output-count"),
i18n("The number of windows to open as outputs in windowed mode. Default value is 1"),
QStringLiteral("count"));
outputCountOption.setDefaultValue(QString::number(1));
QCommandLineParser parser;
a.setupCommandLine(&parser);
parser.addOption(xwaylandOption);
parser.addOption(waylandSocketOption);
if (hasX11Option) {
parser.addOption(x11DisplayOption);
}
if (hasWaylandOption) {
parser.addOption(waylandDisplayOption);
}
if (hasFramebufferOption) {
parser.addOption(framebufferOption);
parser.addOption(framebufferDeviceOption);
}
if (hasVirtualOption) {
parser.addOption(virtualFbOption);
}
if (hasSizeOption) {
parser.addOption(widthOption);
parser.addOption(heightOption);
parser.addOption(scaleOption);
}
if (hasOutputCountOption) {
parser.addOption(outputCountOption);
}
#if HAVE_LIBHYBRIS
QCommandLineOption hwcomposerOption(QStringLiteral("hwcomposer"), i18n("Use libhybris hwcomposer"));
if (hasHwcomposerOption) {
parser.addOption(hwcomposerOption);
}
#endif
QCommandLineOption libinputOption(QStringLiteral("libinput"),
i18n("Enable libinput support for input events processing. Note: never use in a nested session. (deprecated)"));
parser.addOption(libinputOption);
#if HAVE_DRM
QCommandLineOption drmOption(QStringLiteral("drm"), i18n("Render through drm node."));
if (hasDrmOption) {
parser.addOption(drmOption);
}
#endif
QCommandLineOption inputMethodOption(QStringLiteral("inputmethod"),
i18n("Input method that KWin starts."),
QStringLiteral("path/to/imserver"));
parser.addOption(inputMethodOption);
QCommandLineOption listBackendsOption(QStringLiteral("list-backends"),
i18n("List all available backends and quit."));
parser.addOption(listBackendsOption);
QCommandLineOption screenLockerOption(QStringLiteral("lockscreen"),
i18n("Starts the session in locked mode."));
parser.addOption(screenLockerOption);
QCommandLineOption noScreenLockerOption(QStringLiteral("no-lockscreen"),
i18n("Starts the session without lock screen support."));
parser.addOption(noScreenLockerOption);
QCommandLineOption noGlobalShortcutsOption(QStringLiteral("no-global-shortcuts"),
i18n("Starts the session without global shortcuts support."));
parser.addOption(noGlobalShortcutsOption);
QCommandLineOption exitWithSessionOption(QStringLiteral("exit-with-session"),
i18n("Exit after the session application, which is started by KWin, closed."),
QStringLiteral("/path/to/session"));
parser.addOption(exitWithSessionOption);
parser.addPositionalArgument(QStringLiteral("applications"),
i18n("Applications to start once Wayland and Xwayland server are started"),
QStringLiteral("[/path/to/application...]"));
parser.process(a);
a.processCommandLine(&parser);
#ifdef KWIN_BUILD_ACTIVITIES
a.setUseKActivities(false);
#endif
if (parser.isSet(listBackendsOption)) {
for (const auto &plugin: availablePlugins) {
std::cout << std::setw(40) << std::left << qPrintable(plugin.name()) << qPrintable(plugin.description()) << std::endl;
}
return 0;
}
if (parser.isSet(exitWithSessionOption)) {
a.setSessionArgument(parser.value(exitWithSessionOption));
}
KWin::Application::setUseLibinput(parser.isSet(libinputOption));
QString pluginName;
QSize initialWindowSize;
QByteArray deviceIdentifier;
int outputCount = 1;
qreal outputScale = 1;
#if HAVE_DRM
if (hasDrmOption && parser.isSet(drmOption)) {
pluginName = KWin::s_drmPlugin;
}
#endif
if (hasSizeOption) {
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;
}
const qreal scale = parser.value(scaleOption).toDouble(&ok);
if (!ok || scale <= 0) {
std::cerr << "FATAL ERROR incorrect value for scale" << std::endl;
return 1;
}
outputScale = scale;
initialWindowSize = QSize(width, height);
}
if (hasOutputCountOption) {
bool ok = false;
const int count = parser.value(outputCountOption).toInt(&ok);
if (ok) {
outputCount = qMax(1, count);
}
}
if (hasX11Option && parser.isSet(x11DisplayOption)) {
deviceIdentifier = parser.value(x11DisplayOption).toUtf8();
pluginName = KWin::s_x11Plugin;
} else if (hasWaylandOption && parser.isSet(waylandDisplayOption)) {
deviceIdentifier = parser.value(waylandDisplayOption).toUtf8();
pluginName = KWin::s_waylandPlugin;
}
if (hasFramebufferOption && parser.isSet(framebufferOption)) {
pluginName = KWin::s_fbdevPlugin;
deviceIdentifier = parser.value(framebufferDeviceOption).toUtf8();
}
#if HAVE_LIBHYBRIS
if (hasHwcomposerOption && parser.isSet(hwcomposerOption)) {
pluginName = KWin::s_hwcomposerPlugin;
}
#endif
if (hasVirtualOption && parser.isSet(virtualFbOption)) {
pluginName = KWin::s_virtualPlugin;
}
if (pluginName.isEmpty()) {
std::cerr << "No backend specified through command line argument, trying auto resolution" << std::endl;
pluginName = KWin::automaticBackendSelection();
}
auto pluginIt = std::find_if(availablePlugins.begin(), availablePlugins.end(),
[&pluginName] (const KPluginMetaData &plugin) {
return plugin.pluginId() == pluginName;
}
);
if (pluginIt == availablePlugins.end()) {
std::cerr << "FATAL ERROR: could not find a backend" << std::endl;
return 1;
}
// TODO: create backend without having the server running
KWin::WaylandServer *server = KWin::WaylandServer::create(&a);
KWin::WaylandServer::InitializationFlags flags;
if (parser.isSet(screenLockerOption)) {
flags = KWin::WaylandServer::InitializationFlag::LockScreen;
} else if (parser.isSet(noScreenLockerOption)) {
flags = KWin::WaylandServer::InitializationFlag::NoLockScreenIntegration;
}
if (parser.isSet(noGlobalShortcutsOption)) {
flags |= KWin::WaylandServer::InitializationFlag::NoGlobalShortcuts;
}
if (!server->init(parser.value(waylandSocketOption).toUtf8(), flags)) {
std::cerr << "FATAL ERROR: could not create Wayland server" << std::endl;
return 1;
}
a.initPlatform(*pluginIt);
if (!a.platform()) {
std::cerr << "FATAL ERROR: could not instantiate a backend" << std::endl;
return 1;
}
if (!deviceIdentifier.isEmpty()) {
a.platform()->setDeviceIdentifier(deviceIdentifier);
}
if (initialWindowSize.isValid()) {
a.platform()->setInitialWindowSize(initialWindowSize);
}
a.platform()->setInitialOutputScale(outputScale);
a.platform()->setInitialOutputCount(outputCount);
QObject::connect(&a, &KWin::Application::workspaceCreated, server, &KWin::WaylandServer::initWorkspace);
environment.insert(QStringLiteral("WAYLAND_DISPLAY"), server->display()->socketName());
a.setProcessStartupEnvironment(environment);
a.setStartXwayland(parser.isSet(xwaylandOption));
a.setApplicationsToStart(parser.positionalArguments());
a.setInputMethodServerToStart(parser.value(inputMethodOption));
a.start();
return a.exec();
}