cube: Port Wayland impl from wl-shell to xdg-shell

This change ports vkcube in both C and C++ versions to use the stable
xdg-shell protocol for Wayland compositors. The original wl-shell
protocol has been deprecated and is being removed from major compositor
libraries; wlroots has already dropped support.

New cmake modules have been added to look for Wayland-Protocols
(containing XML descriptions of all common protocols) and
`wayland-scanner`, the tool used to convert the XML files to a usable C
interface.

The change also adds support for the xdg-decoration protocol, which for
some compositors is provided and needed to let them know that they
should draw a titlebar, borders with resize controls, and other standard
features.

Change-Id: I39bedda93a7c5d0aeeb59c68023552723b413567

1 files changed, 84 insertions, 22 deletions

diff --git a/cube/cube.c b/cube/cube.c
index dc5c5705..f8da4f6b 100644
--- a/cube/cube.c
+++ b/cube/cube.c
@@ -37,6 +37,8 @@
 #include <X11/Xutil.h>
 #elif defined(VK_USE_PLATFORM_WAYLAND_KHR)
 #include <linux/input.h>
+#include "xdg-shell-client-header.h"
+#include "xdg-decoration-client-header.h"
 #endif
 
 #ifdef _WIN32
@@ -324,8 +326,12 @@ struct demo {
     struct wl_registry *registry;
     struct wl_compositor *compositor;
     struct wl_surface *window;
-    struct wl_shell *shell;
-    struct wl_shell_surface *shell_surface;
+    struct xdg_wm_base *xdg_wm_base;
+    struct zxdg_decoration_manager_v1 *xdg_decoration_mgr;
+    struct zxdg_toplevel_decoration_v1 *toplevel_decoration;
+    struct xdg_surface *xdg_surface;
+    int xdg_surface_has_been_configured;
+    struct xdg_toplevel *xdg_toplevel;
     struct wl_seat *seat;
     struct wl_pointer *pointer;
     struct wl_keyboard *keyboard;
@@ -2374,9 +2380,14 @@ static void demo_cleanup(struct demo *demo) {
     wl_keyboard_destroy(demo->keyboard);
     wl_pointer_destroy(demo->pointer);
     wl_seat_destroy(demo->seat);
-    wl_shell_surface_destroy(demo->shell_surface);
+    xdg_toplevel_destroy(demo->xdg_toplevel);
+    xdg_surface_destroy(demo->xdg_surface);
     wl_surface_destroy(demo->window);
-    wl_shell_destroy(demo->shell);
+    xdg_wm_base_destroy(demo->xdg_wm_base);
+    if (demo->xdg_decoration_mgr) {
+        zxdg_toplevel_decoration_v1_destroy(demo->toplevel_decoration);
+        zxdg_decoration_manager_v1_destroy(demo->xdg_decoration_mgr);
+    }
     wl_compositor_destroy(demo->compositor);
     wl_registry_destroy(demo->registry);
     wl_display_disconnect(demo->display);
@@ -2757,18 +2768,45 @@ static void demo_run(struct demo *demo) {
     }
 }
 
-static void handle_ping(void *data UNUSED, struct wl_shell_surface *shell_surface, uint32_t serial) {
-    wl_shell_surface_pong(shell_surface, serial);
+static void handle_surface_configure(void *data, struct xdg_surface *xdg_surface, uint32_t serial) {
+    struct demo *demo = (struct demo *)data;
+    xdg_surface_ack_configure(xdg_surface, serial);
+    if (demo->xdg_surface_has_been_configured) {
+        demo_resize(demo);
+    }
+    demo->xdg_surface_has_been_configured = 1;
 }
 
-static void handle_configure(void *data UNUSED, struct wl_shell_surface *shell_surface UNUSED, uint32_t edges UNUSED,
-                             int32_t width UNUSED, int32_t height UNUSED) {}
+static const struct xdg_surface_listener xdg_surface_listener = {handle_surface_configure};
+
+static void handle_toplevel_configure(void *data, struct xdg_toplevel *xdg_toplevel UNUSED, int32_t width, int32_t height,
+                                      struct wl_array *states UNUSED) {
+    struct demo *demo = (struct demo *)data;
+    /* zero values imply the program may choose its own size, so in that case
+     * stay with the existing value (which on startup is the default) */
+    if (width > 0) {
+        demo->width = width;
+    }
+    if (height > 0) {
+        demo->height = height;
+    }
+    /* This should be followed by a surface configure */
+}
 
-static void handle_popup_done(void *data UNUSED, struct wl_shell_surface *shell_surface UNUSED) {}
+static void handle_toplevel_close(void *data, struct xdg_toplevel *xdg_toplevel UNUSED) {
+    struct demo *demo = (struct demo *)data;
+    demo->quit = true;
+}
 
-static const struct wl_shell_surface_listener shell_surface_listener = {handle_ping, handle_configure, handle_popup_done};
+static const struct xdg_toplevel_listener xdg_toplevel_listener = {handle_toplevel_configure, handle_toplevel_close};
 
 static void demo_create_window(struct demo *demo) {
+    if (!demo->xdg_wm_base) {
+        printf("Compositor did not provide the standard protocol xdg-wm-base\n");
+        fflush(stdout);
+        exit(1);
+    }
+
     demo->window = wl_compositor_create_surface(demo->compositor);
     if (!demo->window) {
         printf("Can not create wayland_surface from compositor!\n");
@@ -2776,15 +2814,29 @@ static void demo_create_window(struct demo *demo) {
         exit(1);
     }
 
-    demo->shell_surface = wl_shell_get_shell_surface(demo->shell, demo->window);
-    if (!demo->shell_surface) {
-        printf("Can not get shell_surface from wayland_surface!\n");
+    demo->xdg_surface = xdg_wm_base_get_xdg_surface(demo->xdg_wm_base, demo->window);
+    if (!demo->xdg_surface) {
+        printf("Can not get xdg_surface from wayland_surface!\n");
+        fflush(stdout);
+        exit(1);
+    }
+    demo->xdg_toplevel = xdg_surface_get_toplevel(demo->xdg_surface);
+    if (!demo->xdg_toplevel) {
+        printf("Can not allocate xdg_toplevel for xdg_surface!\n");
         fflush(stdout);
         exit(1);
     }
-    wl_shell_surface_add_listener(demo->shell_surface, &shell_surface_listener, demo);
-    wl_shell_surface_set_toplevel(demo->shell_surface);
-    wl_shell_surface_set_title(demo->shell_surface, APP_SHORT_NAME);
+    xdg_surface_add_listener(demo->xdg_surface, &xdg_surface_listener, demo);
+    xdg_toplevel_add_listener(demo->xdg_toplevel, &xdg_toplevel_listener, demo);
+    xdg_toplevel_set_title(demo->xdg_toplevel, APP_SHORT_NAME);
+    if (demo->xdg_decoration_mgr) {
+        // if supported, let the compositor render titlebars for us
+        demo->toplevel_decoration =
+            zxdg_decoration_manager_v1_get_toplevel_decoration(demo->xdg_decoration_mgr, demo->xdg_toplevel);
+        zxdg_toplevel_decoration_v1_set_mode(demo->toplevel_decoration, ZXDG_TOPLEVEL_DECORATION_V1_MODE_SERVER_SIDE);
+    }
+
+    wl_surface_commit(demo->window);
 }
 #elif defined(VK_USE_PLATFORM_DIRECTFB_EXT)
 static void demo_create_directfb_window(struct demo *demo) {
@@ -3746,7 +3798,7 @@ static void pointer_handle_button(void *data, struct wl_pointer *wl_pointer, uin
                                   uint32_t state) {
     struct demo *demo = data;
     if (button == BTN_LEFT && state == WL_POINTER_BUTTON_STATE_PRESSED) {
-        wl_shell_surface_move(demo->shell_surface, demo->seat, serial);
+        xdg_toplevel_move(demo->xdg_toplevel, demo->seat, serial);
     }
 }
 
@@ -3814,21 +3866,31 @@ static const struct wl_seat_listener seat_listener = {
     seat_handle_capabilities,
 };
 
-static void registry_handle_global(void *data, struct wl_registry *registry, uint32_t id, const char *interface, uint32_t version) {
+static void wm_base_ping(void *data UNUSED, 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 wm_base_listener = {wm_base_ping};
+
+static void registry_handle_global(void *data, struct wl_registry *registry, uint32_t id, const char *interface,
+                                   uint32_t version UNUSED) {
     struct demo *demo = data;
     // pickup wayland objects when they appear
-    if (strcmp(interface, "wl_compositor") == 0) {
+    if (strcmp(interface, wl_compositor_interface.name) == 0) {
         uint32_t minVersion = version < 4 ? version : 4;
         demo->compositor = wl_registry_bind(registry, id, &wl_compositor_interface, minVersion);
         if (demo->VK_KHR_incremental_present_enabled && minVersion < 4) {
             fprintf(stderr, "Wayland compositor doesn't support VK_KHR_incremental_present, disabling.\n");
             demo->VK_KHR_incremental_present_enabled = false;
         }
-    } else if (strcmp(interface, "wl_shell") == 0) {
-        demo->shell = wl_registry_bind(registry, id, &wl_shell_interface, 1);
-    } else if (strcmp(interface, "wl_seat") == 0) {
+    } else if (strcmp(interface, xdg_wm_base_interface.name) == 0) {
+        demo->xdg_wm_base = wl_registry_bind(registry, id, &xdg_wm_base_interface, 1);
+        xdg_wm_base_add_listener(demo->xdg_wm_base, &wm_base_listener, NULL);
+    } else if (strcmp(interface, wl_seat_interface.name) == 0) {
         demo->seat = wl_registry_bind(registry, id, &wl_seat_interface, 1);
         wl_seat_add_listener(demo->seat, &seat_listener, demo);
+    } else if (strcmp(interface, zxdg_decoration_manager_v1_interface.name) == 0) {
+        demo->xdg_decoration_mgr = wl_registry_bind(registry, id, &zxdg_decoration_manager_v1_interface, 1);
     }
 }