feat(slock): implement ext_session_lock_v1 backend

note: did not run lints or fully test yet

src/wayland/session_lock/surface.cpp

@@ -0,0 +1,111 @@
+#include "surface.hpp"
+
+#include <private/qwaylandscreen_p.h>
+#include <private/qwaylandshellsurface_p.h>
+#include <private/qwaylandshmbackingstore_p.h>
+#include <private/qwaylandsurface_p.h>
+#include <private/qwaylandwindow_p.h>
+#include <qlogging.h>
+#include <qobject.h>
+#include <wayland-client-protocol.h>
+
+#include "lock.hpp"
+#include "session_lock.hpp"
+
+QSWaylandSessionLockSurface::QSWaylandSessionLockSurface(QtWaylandClient::QWaylandWindow* window)
+    : QtWaylandClient::QWaylandShellSurface(window) {
+	auto* qwindow = window->window();
+	this->setExtension(LockWindowExtension::get(qwindow));
+
+	if (this->ext == nullptr) {
+		qFatal() << "QSWaylandSessionLockSurface created with null LockWindowExtension";
+		throw nullptr;
+	}
+
+	if (this->ext->lock == nullptr) {
+		qFatal() << "QSWaylandSessionLock for QSWaylandSessionLockSurface died";
+		throw nullptr;
+	}
+
+	wl_output* output = nullptr;
+	auto* waylandScreen = dynamic_cast<QtWaylandClient::QWaylandScreen*>(qwindow->screen()->handle());
+
+	if (waylandScreen != nullptr) {
+		output = waylandScreen->output();
+	} else {
+		qFatal() << "Session lock screen does not corrospond to a real screen. Force closing window";
+		throw nullptr;
+	}
+
+	this->init(this->ext->lock->get_lock_surface(window->waylandSurface()->object(), output));
+}
+
+QSWaylandSessionLockSurface::~QSWaylandSessionLockSurface() { this->destroy(); }
+
+bool QSWaylandSessionLockSurface::isExposed() const { return this->configured; }
+
+void QSWaylandSessionLockSurface::applyConfigure() {
+	this->window()->resizeFromApplyConfigure(this->size);
+}
+
+bool QSWaylandSessionLockSurface::handleExpose(const QRegion& region) {
+	if (this->initBuf != nullptr) {
+		// at this point qt's next commit to the surface will have a new buffer, and we can safely delete this one.
+		delete this->initBuf;
+		this->initBuf = nullptr;
+	}
+
+	return this->QtWaylandClient::QWaylandShellSurface::handleExpose(region);
+}
+
+void QSWaylandSessionLockSurface::setExtension(LockWindowExtension* ext) {
+	if (ext == nullptr) {
+		this->window()->window()->close();
+	} else {
+		if (this->ext != nullptr) {
+			this->ext->surface = nullptr;
+		}
+
+		this->ext = ext;
+		this->ext->surface = this;
+	}
+}
+
+void QSWaylandSessionLockSurface::setVisible() {
+	if (this->configured && !this->visible) initVisible();
+	this->visible = true;
+}
+
+void QSWaylandSessionLockSurface::ext_session_lock_surface_v1_configure(
+    quint32 serial,
+    quint32 width,
+    quint32 height
+) {
+	this->ack_configure(serial);
+
+	this->size = QSize(static_cast<qint32>(width), static_cast<qint32>(height));
+	if (!this->configured) {
+		this->configured = true;
+
+		this->window()->resizeFromApplyConfigure(this->size);
+		this->window()->handleExpose(QRect(QPoint(), this->size));
+		if (this->visible) initVisible();
+	} else {
+		this->window()->applyConfigureWhenPossible();
+	}
+}
+
+void QSWaylandSessionLockSurface::initVisible() {
+	this->visible = true;
+
+	// qt always commits a null buffer in QWaylandWindow::initWindow.
+	// We attach a dummy buffer to satisfy ext_session_lock_v1.
+	this->initBuf = new QtWaylandClient::QWaylandShmBuffer(
+	    this->window()->display(),
+	    size,
+	    QImage::Format_ARGB32
+	);
+
+	this->window()->waylandSurface()->attach(initBuf->buffer(), 0, 0);
+	this->window()->window()->setVisible(true);
+}