xwayland: port rooted xwayland from wl_shell to xdg-shell protocol

Recently, rooted Xwayland crashes on wlroots-based compositors, because
wlroots removed the deprecated wl_shell protocol.
This MR fixes this by changing the code in question to the xdg-shell
protocol. My motivation do this: on etnaviv-based embedded platforms,
rooted Xwayland is much faster and doesn't cause UI rendering bugs
compared to rootless Xwayland.
Signed-off-by: Lukas F. Hartmann <lukas@mntre.com>

hw/xwayland/Makefile.am

@@ -100,7 +100,9 @@ Xwayland_built_sources +=					\
 	linux-dmabuf-unstable-v1-client-protocol.h		\
 	linux-dmabuf-unstable-v1-protocol.c			\
 	viewporter-client-protocol.h				\
-	viewporter-protocol.c
+	viewporter-protocol.c\
+	xdg-shell-client-protocol.h\
+	xdg-shell-protocol.c
 
 if XWAYLAND_EGLSTREAM
 Xwayland_built_sources +=					\
@@ -154,6 +156,11 @@ viewporter-protocol.c: $(WAYLAND_PROTOCOLS_DATADIR)/stable/viewporter/viewporter
 viewporter-client-protocol.h: $(WAYLAND_PROTOCOLS_DATADIR)/stable/viewporter/viewporter.xml
 	$(AM_V_GEN)$(WAYLAND_SCANNER) client-header < $< > $@
 
+xdg-shell-protocol.c: $(WAYLAND_PROTOCOLS_DATADIR)/stable/xdg-shell/xdg-shell.xml
+	$(AM_V_GEN)$(WAYLAND_SCANNER) @SCANNER_ARG@ < $< > $@
+xdg-shell-client-protocol.h: $(WAYLAND_PROTOCOLS_DATADIR)/stable/xdg-shell/xdg-shell.xml
+	$(AM_V_GEN)$(WAYLAND_SCANNER) client-header < $< > $@
+
 wayland-eglstream-client-protocol.h : $(WAYLAND_EGLSTREAM_DATADIR)/wayland-eglstream.xml
 	$(AM_V_GEN)$(WAYLAND_SCANNER) client-header < $< > $@
 wayland-eglstream-controller-client-protocol.h : $(WAYLAND_EGLSTREAM_DATADIR)/wayland-eglstream-controller.xml

hw/xwayland/meson.build

@@ -40,6 +40,7 @@ kbgrab_xml = join_paths(protodir, 'unstable', 'xwayland-keyboard-grab', 'xwaylan
 xdg_output_xml = join_paths(protodir, 'unstable', 'xdg-output', 'xdg-output-unstable-v1.xml')
 dmabuf_xml = join_paths(protodir, 'unstable', 'linux-dmabuf', 'linux-dmabuf-unstable-v1.xml')
 viewporter_xml = join_paths(protodir, 'stable', 'viewporter', 'viewporter.xml')
+xdg_shell_xml = join_paths(protodir, 'stable', 'xdg-shell', 'xdg-shell.xml')
 
 client_header = generator(scanner,
     output : '@BASENAME@-client-protocol.h',
@@ -63,6 +64,7 @@ srcs += client_header.process(kbgrab_xml)
 srcs += client_header.process(xdg_output_xml)
 srcs += client_header.process(dmabuf_xml)
 srcs += client_header.process(viewporter_xml)
+srcs += client_header.process(xdg_shell_xml)
 srcs += code.process(relative_xml)
 srcs += code.process(pointer_xml)
 srcs += code.process(tablet_xml)
@@ -70,6 +72,7 @@ srcs += code.process(kbgrab_xml)
 srcs += code.process(xdg_output_xml)
 srcs += code.process(dmabuf_xml)
 srcs += code.process(viewporter_xml)
+srcs += code.process(xdg_shell_xml)
 
 xwayland_glamor = []
 eglstream_srcs = []

hw/xwayland/xwayland-screen.c

@@ -54,6 +54,7 @@
 
 #include "xdg-output-unstable-v1-client-protocol.h"
 #include "viewporter-client-protocol.h"
+#include "xdg-shell-client-protocol.h"
 
 static DevPrivateKeyRec xwl_screen_private_key;
 static DevPrivateKeyRec xwl_client_private_key;
@@ -318,6 +319,17 @@ xwl_screen_post_damage(struct xwl_screen *xwl_screen)
     }
 }
 
+static void
+xdg_wm_base_ping(void *data, struct xdg_wm_base *xdg_wm_base,
+                 uint32_t serial)
+{
+    xdg_wm_base_pong(xdg_wm_base, serial);
+}
+
+static const struct xdg_wm_base_listener xdg_wm_base_listener = {
+    xdg_wm_base_ping,
+};
+
 static void
 registry_global(void *data, struct wl_registry *registry, uint32_t id,
                 const char *interface, uint32_t version)
@@ -336,9 +348,12 @@ registry_global(void *data, struct wl_registry *registry, uint32_t id,
     else if (strcmp(interface, "wl_shm") == 0) {
         xwl_screen->shm = wl_registry_bind(registry, id, &wl_shm_interface, 1);
     }
-    else if (strcmp(interface, "wl_shell") == 0) {
-        xwl_screen->shell =
-            wl_registry_bind(registry, id, &wl_shell_interface, 1);
+    else if (strcmp(interface, "xdg_wm_base") == 0) {
+        xwl_screen->xdg_wm_base =
+            wl_registry_bind(registry, id, &xdg_wm_base_interface, 1);
+        xdg_wm_base_add_listener(xwl_screen->xdg_wm_base,
+                                 &xdg_wm_base_listener,
+                                 NULL);
     }
     else if (strcmp(interface, "wl_output") == 0 && version >= 2) {
         if (xwl_output_create(xwl_screen, id))

hw/xwayland/xwayland-screen.h

@@ -79,7 +79,7 @@ struct xwl_screen {
     struct wl_compositor *compositor;
     struct zwp_tablet_manager_v2 *tablet_manager;
     struct wl_shm *shm;
-    struct wl_shell *shell;
+    struct xdg_wm_base *xdg_wm_base;
     struct zwp_relative_pointer_manager_v1 *relative_pointer_manager;
     struct zwp_pointer_constraints_v1 *pointer_constraints;
     struct zwp_xwayland_keyboard_grab_manager_v1 *wp_grab;

hw/xwayland/xwayland-window.c

@@ -44,6 +44,7 @@
 #include "xwayland-shm.h"
 
 #include "viewporter-client-protocol.h"
+#include "xdg-shell-client-protocol.h"
 
 static DevPrivateKeyRec xwl_window_private_key;
 static DevPrivateKeyRec xwl_damage_private_key;
@@ -401,28 +402,15 @@ send_surface_id_event(struct xwl_window *xwl_window)
 }
 
 static void
-shell_surface_ping(void *data,
-                   struct wl_shell_surface *shell_surface, uint32_t serial)
+xdg_surface_handle_configure(void *data,
+                             struct xdg_surface *xdg_surface,
+                             uint32_t serial)
 {
-    wl_shell_surface_pong(shell_surface, serial);
+    xdg_surface_ack_configure(xdg_surface, serial);
 }
 
-static void
-shell_surface_configure(void *data,
-                        struct wl_shell_surface *wl_shell_surface,
-                        uint32_t edges, int32_t width, int32_t height)
-{
-}
-
-static void
-shell_surface_popup_done(void *data, struct wl_shell_surface *wl_shell_surface)
-{
-}
-
-static const struct wl_shell_surface_listener shell_surface_listener = {
-    shell_surface_ping,
-    shell_surface_configure,
-    shell_surface_popup_done
+static const struct xdg_surface_listener xdg_surface_listener = {
+    xdg_surface_handle_configure,
 };
 
 static Bool
@@ -461,17 +449,19 @@ ensure_surface_for_window(WindowPtr window)
     }
 
     if (!xwl_screen->rootless) {
-        xwl_window->shell_surface =
-            wl_shell_get_shell_surface(xwl_screen->shell, xwl_window->surface);
-        if (xwl_window->shell_surface == NULL) {
-            ErrorF("Failed creating shell surface\n");
+        xwl_window->xdg_surface =
+            xdg_wm_base_get_xdg_surface(xwl_screen->xdg_wm_base, xwl_window->surface);
+        if (xwl_window->xdg_surface == NULL) {
+            ErrorF("Failed creating xdg_wm_base xdg_surface\n");
             goto err_surf;
         }
 
-        wl_shell_surface_add_listener(xwl_window->shell_surface,
-                                      &shell_surface_listener, xwl_window);
+        xdg_surface_add_listener(xwl_window->xdg_surface,
+                                 &xdg_surface_listener, xwl_window);
+
+        xdg_surface_get_toplevel(xwl_window->xdg_surface);
 
-        wl_shell_surface_set_toplevel(xwl_window->shell_surface);
+        wl_surface_commit(xwl_window->surface);
 
         region = wl_compositor_create_region(xwl_screen->compositor);
         if (region == NULL) {
@@ -520,8 +510,8 @@ ensure_surface_for_window(WindowPtr window)
     return TRUE;
 
 err_surf:
-    if (xwl_window->shell_surface)
-        wl_shell_surface_destroy(xwl_window->shell_surface);
+    if (xwl_window->xdg_surface)
+        xdg_surface_destroy(xwl_window->xdg_surface);
     wl_surface_destroy(xwl_window->surface);
 err:
     free(xwl_window);

hw/xwayland/xwayland-window.h

@@ -42,7 +42,7 @@ struct xwl_window {
     struct wl_surface *surface;
     struct wp_viewport *viewport;
     float scale_x, scale_y;
-    struct wl_shell_surface *shell_surface;
+    struct xdg_surface *xdg_surface;
     WindowPtr window;
     struct xorg_list link_damage;
     struct xorg_list link_window;