Revert "Revert "Add main window shadow for Linux""

This reverts commit b7f5cfe083.

Telegram/SourceFiles/platform/linux/specific_linux.cpp

@@ -81,6 +81,8 @@ constexpr auto kXDGDesktopPortalService = "org.freedesktop.portal.Desktop"_cs;
 constexpr auto kXDGDesktopPortalObjectPath = "/org/freedesktop/portal/desktop"_cs;
 constexpr auto kPropertiesInterface = "org.freedesktop.DBus.Properties"_cs;
 
+constexpr auto kXCBFrameExtentsAtomName = "_GTK_FRAME_EXTENTS"_cs;
+
 QStringList PlatformThemes;
 
 bool IsTrayIconSupported = true;
@@ -298,6 +300,91 @@ bool GetImageFromClipboardSupported() {
 }
 #endif // !TDESKTOP_DISABLE_GTK_INTEGRATION
 
+std::optional<xcb_atom_t> GetXCBAtom(
+		xcb_connection_t *connection,
+		const QString &name) {
+	const auto cookie = xcb_intern_atom(
+		connection,
+		0,
+		name.size(),
+		name.toUtf8());
+
+	auto reply = xcb_intern_atom_reply(
+		connection,
+		cookie,
+		nullptr);
+
+	if (!reply) {
+		return std::nullopt;
+	}
+
+	const auto atom = reply->atom;
+	free(reply);
+
+	return atom;
+}
+
+std::vector<xcb_atom_t> GetXCBWMSupported(xcb_connection_t *connection) {
+	auto netWmAtoms = std::vector<xcb_atom_t>{};
+
+	const auto native = QGuiApplication::platformNativeInterface();
+	if (!native) {
+		return netWmAtoms;
+	}
+
+	const auto root = static_cast<xcb_window_t>(reinterpret_cast<quintptr>(
+		native->nativeResourceForIntegration(QByteArray("rootwindow"))));
+
+	const auto supportedAtom = GetXCBAtom(connection, "_NET_SUPPORTED");
+	if (!supportedAtom.has_value()) {
+		return netWmAtoms;
+	}
+
+	auto offset = 0;
+	auto remaining = 0;
+
+	do {
+		const auto cookie = xcb_get_property(
+			connection,
+			false,
+			root,
+			*supportedAtom,
+			XCB_ATOM_ATOM,
+			offset,
+			1024);
+
+		auto reply = xcb_get_property_reply(
+			connection,
+			cookie,
+			nullptr);
+
+		if (!reply) {
+			break;
+		}
+
+		remaining = 0;
+
+		if (reply->type == XCB_ATOM_ATOM && reply->format == 32) {
+			const auto len = xcb_get_property_value_length(reply)
+				/ sizeof(xcb_atom_t);
+
+			const auto atoms = reinterpret_cast<xcb_atom_t*>(
+				xcb_get_property_value(reply));
+
+			const auto s = netWmAtoms.size();
+			netWmAtoms.resize(s + len);
+			memcpy(netWmAtoms.data() + s, atoms, len * sizeof(xcb_atom_t));
+
+			remaining = reply->bytes_after;
+			offset += len;
+		}
+
+		free(reply);
+	} while (remaining > 0);
+
+	return netWmAtoms;
+}
+
 std::optional<crl::time> XCBLastUserInputTime() {
 	const auto native = QGuiApplication::platformNativeInterface();
 	if (!native) {
@@ -311,24 +398,24 @@ std::optional<crl::time> XCBLastUserInputTime() {
 		return std::nullopt;
 	}
 
-	const auto screen = xcb_setup_roots_iterator(xcb_get_setup(connection)).data;
-	if (!screen) {
-		return std::nullopt;
-	}
+	const auto root = static_cast<xcb_window_t>(reinterpret_cast<quintptr>(
+		native->nativeResourceForIntegration(QByteArray("rootwindow"))));
 
-	const auto cookie = xcb_screensaver_query_info(connection, screen->root);
+	const auto cookie = xcb_screensaver_query_info(
+		connection,
+		root);
 
-	auto info = xcb_screensaver_query_info_reply(
+	auto reply = xcb_screensaver_query_info_reply(
 		connection,
 		cookie,
 		nullptr);
 
-	if (!info) {
+	if (!reply) {
 		return std::nullopt;
 	}
 
-	const auto idle = info->ms_since_user_input;
-	free(info);
+	const auto idle = reply->ms_since_user_input;
+	free(reply);
 
 	return (crl::now() - static_cast<crl::time>(idle));
 }
@@ -468,7 +555,6 @@ enum wl_shell_surface_resize WlResizeFromEdges(Qt::Edges edges) {
 
 bool StartXCBMoveResize(QWindow *window, int edges) {
 	const auto native = QGuiApplication::platformNativeInterface();
-
 	if (!native) {
 		return false;
 	}
@@ -487,29 +573,16 @@ bool StartXCBMoveResize(QWindow *window, int edges) {
 		return false;
 	}
 
-	const auto moveResizeCookie = xcb_intern_atom(
-		connection,
-		0,
-		strlen("_NET_WM_MOVERESIZE"),
-		"_NET_WM_MOVERESIZE");
-
-	auto moveResizeReply = xcb_intern_atom_reply(
-		connection,
-		moveResizeCookie,
-		nullptr);
-
-	if (!moveResizeReply) {
+	const auto moveResize = GetXCBAtom(connection, "_NET_WM_MOVERESIZE");
+	if (!moveResize.has_value()) {
 		return false;
 	}
 
-	const auto moveResize = moveResizeReply->atom;
-	free(moveResizeReply);
-
 	const auto globalPos = QCursor::pos();
 
 	xcb_client_message_event_t xev;
 	xev.response_type = XCB_CLIENT_MESSAGE;
-	xev.type = moveResize;
+	xev.type = *moveResize;
 	xev.sequence = 0;
 	xev.window = window->winId();
 	xev.format = 32;
@@ -582,6 +655,87 @@ bool ShowWaylandWindowMenu(QWindow *window) {
 	return false;
 }
 
+bool XCBFrameExtentsSupported() {
+	const auto native = QGuiApplication::platformNativeInterface();
+	if (!native) {
+		return false;
+	}
+
+	const auto connection = reinterpret_cast<xcb_connection_t*>(
+		native->nativeResourceForIntegration(QByteArray("connection")));
+
+	if (!connection) {
+		return false;
+	}
+
+	const auto frameExtentsAtom = GetXCBAtom(
+		connection,
+		kXCBFrameExtentsAtomName.utf16());
+
+	if (!frameExtentsAtom.has_value()) {
+		return false;
+	}
+
+	return ranges::contains(GetXCBWMSupported(connection), *frameExtentsAtom);
+}
+
+bool SetXCBFrameExtents(QWindow *window, const QMargins &extents) {
+	const auto native = QGuiApplication::platformNativeInterface();
+	if (!native) {
+		return false;
+	}
+
+	const auto connection = reinterpret_cast<xcb_connection_t*>(
+		native->nativeResourceForIntegration(QByteArray("connection")));
+
+	if (!connection) {
+		return false;
+	}
+
+	const auto frameExtentsAtom = GetXCBAtom(
+		connection,
+		kXCBFrameExtentsAtomName.utf16());
+
+	if (!frameExtentsAtom.has_value()) {
+		return false;
+	}
+
+	const auto extentsVector = std::vector<uint>{
+		uint(extents.left()),
+		uint(extents.right()),
+		uint(extents.top()),
+		uint(extents.bottom()),
+	};
+
+	xcb_change_property(
+		connection,
+		XCB_PROP_MODE_REPLACE,
+		window->winId(),
+		*frameExtentsAtom,
+		XCB_ATOM_CARDINAL,
+		32,
+		extentsVector.size(),
+		extentsVector.data());
+
+	return true;
+}
+
+bool SetWaylandWindowGeometry(QWindow *window, const QRect &geometry) {
+#if QT_VERSION >= QT_VERSION_CHECK(5, 13, 0) || defined DESKTOP_APP_QT_PATCHED
+	if (const auto waylandWindow = static_cast<QWaylandWindow*>(
+		window->handle())) {
+		if (const auto seat = waylandWindow->display()->lastInputDevice()) {
+			if (const auto shellSurface = waylandWindow->shellSurface()) {
+				shellSurface->setWindowGeometry(geometry);
+				return true;
+			}
+		}
+	}
+#endif // Qt >= 5.13 || DESKTOP_APP_QT_PATCHED
+
+	return false;
+}
+
 Window::Control GtkKeywordToWindowControl(const QString &keyword) {
 	if (keyword == qstr("minimize")) {
 		return Window::Control::Minimize;
@@ -926,6 +1080,31 @@ bool ShowWindowMenu(QWindow *window) {
 	return false;
 }
 
+bool SetWindowExtents(QWindow *window, const QMargins &extents) {
+	if (IsWayland()) {
+		const auto geometry = QRect(QPoint(), window->size())
+			.marginsRemoved(extents);
+
+		return SetWaylandWindowGeometry(window, geometry);
+	} else {
+		return SetXCBFrameExtents(window, extents);
+	}
+}
+
+bool WindowsNeedShadow() {
+#if QT_VERSION >= QT_VERSION_CHECK(5, 13, 0) || defined DESKTOP_APP_QT_PATCHED
+	if (IsWayland()) {
+		return true;
+	}
+#endif // Qt >= 5.13 || DESKTOP_APP_QT_PATCHED
+
+	if (!IsWayland() && XCBFrameExtentsSupported()) {
+		return true;
+	}
+
+	return false;
+}
+
 Window::ControlsLayout WindowControlsLayout() {
 #ifndef TDESKTOP_DISABLE_GTK_INTEGRATION
 	if (Libs::GtkSettingSupported()