Use WLR_PRIVATE for private fields

CONTRIBUTING.md

@@ -237,6 +237,13 @@ used and `#undef` them after.
 * Document the contents and container of a `struct wl_list` with a
   `// content.link` and `// container.list` comment.
 
+### Private fields
+
+Wrap private fields of public structures with `struct { … } WLR_PRIVATE`. This
+ensures that compositor authors don't use them by accident. Within wlroots
+`WLR_PRIVATE` is expanded to nothing, so private fields are accessed in the same
+way as public ones.
+
 ### Safety
 
 * Avoid string manipulation functions which don't take the size of the
@@ -325,12 +332,14 @@ struct wlr_compositor {
 	struct wl_global *global;
 	…
 
-	struct wl_listener display_destroy;
-
 	struct {
 		struct wl_signal new_surface;
 		struct wl_signal destroy;
 	} events;
+
+	struct {
+		struct wl_listener display_destroy;
+	} WLR_PRIVATE;
 };
 ```
 

include/wlr/render/drm_syncobj.h

@@ -29,9 +29,9 @@ struct wlr_drm_syncobj_timeline {
 	int drm_fd;
 	uint32_t handle;
 
-	// private state
+	struct {
-
 		size_t n_refs;
+	} WLR_PRIVATE;
 };
 
 struct wlr_drm_syncobj_timeline_waiter {
@@ -39,10 +39,10 @@ struct wlr_drm_syncobj_timeline_waiter {
 		struct wl_signal ready;
 	} events;
 
-	// private state
+	struct {
-
 		int ev_fd;
 		struct wl_event_source *event_source;
+	} WLR_PRIVATE;
 };
 
 /**

include/wlr/render/wlr_renderer.h

@@ -53,9 +53,9 @@ struct wlr_renderer {
 		bool timeline;
 	} features;
 
-	// private state
+	struct {
-
 		const struct wlr_renderer_impl *impl;
+	} WLR_PRIVATE;
 };
 
 /**

include/wlr/types/wlr_alpha_modifier_v1.h

@@ -20,9 +20,9 @@ struct wlr_alpha_modifier_surface_v1_state {
 struct wlr_alpha_modifier_v1 {
 	struct wl_global *global;
 
-	// private state
+	struct {
-
 		struct wl_listener display_destroy;
+	} WLR_PRIVATE;
 };
 
 struct wlr_alpha_modifier_v1 *wlr_alpha_modifier_v1_create(struct wl_display *display);

include/wlr/types/wlr_buffer.h

@@ -148,12 +148,12 @@ struct wlr_client_buffer {
 	 */
 	struct wlr_buffer *source;
 
-	// private state
+	struct {
-
 		struct wl_listener source_destroy;
 		struct wl_listener renderer_destroy;
 
 		size_t n_ignore_locks;
+	} WLR_PRIVATE;
 };
 
 /**

include/wlr/types/wlr_compositor.h

@@ -236,8 +236,7 @@ struct wlr_surface {
 	struct wlr_addon_set addons;
 	void *data;
 
-	// private state
+	struct {
-
 		struct wl_listener role_resource_destroy;
 
 		struct {
@@ -263,6 +262,7 @@ struct wlr_surface {
 
 		struct wl_resource *pending_buffer_resource;
 		struct wl_listener pending_buffer_resource_destroy;
+	} WLR_PRIVATE;
 };
 
 struct wlr_renderer;

include/wlr/types/wlr_content_type_v1.h

@@ -23,9 +23,9 @@ struct wlr_content_type_manager_v1 {
 
 	void *data;
 
-	// private state
+	struct {
-
 		struct wl_listener display_destroy;
+	} WLR_PRIVATE;
 };
 
 struct wlr_content_type_manager_v1 *wlr_content_type_manager_v1_create(

include/wlr/types/wlr_cursor_shape_v1.h

@@ -28,9 +28,9 @@ struct wlr_cursor_shape_manager_v1 {
 
 	void *data;
 
-	// private state
+	struct {
-
 		struct wl_listener display_destroy;
+	} WLR_PRIVATE;
 };
 
 enum wlr_cursor_shape_manager_v1_device_type {

include/wlr/types/wlr_damage_ring.h

@@ -30,9 +30,9 @@ struct wlr_damage_ring {
 	// Difference between the current buffer and the previous one
 	pixman_region32_t current;
 
-	// private state
+	struct {
-
 		struct wl_list buffers; // wlr_damage_ring_buffer.link
+	} WLR_PRIVATE;
 };
 
 void wlr_damage_ring_init(struct wlr_damage_ring *ring);

include/wlr/types/wlr_drm.h

@@ -40,12 +40,12 @@ struct wlr_drm {
 		struct wl_signal destroy;
 	} events;
 
-	// private state
+	struct {
-
 		char *node_name;
 		struct wlr_drm_format_set formats;
 
 		struct wl_listener display_destroy;
+	} WLR_PRIVATE;
 };
 
 struct wlr_drm_buffer *wlr_drm_buffer_try_from_resource(

include/wlr/types/wlr_foreign_toplevel_management_v1.h

@@ -39,10 +39,10 @@ struct wlr_foreign_toplevel_handle_v1_output {
 	struct wlr_output *output;
 	struct wlr_foreign_toplevel_handle_v1 *toplevel;
 
-	// private state
+	struct {
-
 		struct wl_listener output_bind;
 		struct wl_listener output_destroy;
+	} WLR_PRIVATE;
 };
 
 struct wlr_foreign_toplevel_handle_v1 {

include/wlr/types/wlr_fractional_scale_v1.h

@@ -20,9 +20,9 @@ struct wlr_fractional_scale_manager_v1 {
 		struct wl_signal destroy;
 	} events;
 
-	// private state
+	struct {
-
 		struct wl_listener display_destroy;
+	} WLR_PRIVATE;
 };
 
 void wlr_fractional_scale_v1_notify_scale(

include/wlr/types/wlr_idle_notify_v1.h

@@ -19,12 +19,12 @@ struct wlr_seat;
 struct wlr_idle_notifier_v1 {
 	struct wl_global *global;
 
-	// private state
+	struct {
-
 		bool inhibited;
 		struct wl_list notifications; // wlr_idle_notification_v1.link
 
 		struct wl_listener display_destroy;
+	} WLR_PRIVATE;
 };
 
 

include/wlr/types/wlr_layer_shell_v1.h

@@ -114,9 +114,9 @@ struct wlr_layer_surface_v1 {
 
 	void *data;
 
-	// private state
+	struct {
-
 		struct wlr_surface_synced synced;
+	} WLR_PRIVATE;
 };
 
 struct wlr_layer_shell_v1 *wlr_layer_shell_v1_create(struct wl_display *display,

include/wlr/types/wlr_linux_dmabuf_v1.h

@@ -24,9 +24,9 @@ struct wlr_dmabuf_v1_buffer {
 	struct wl_resource *resource; // can be NULL if the client destroyed it
 	struct wlr_dmabuf_attributes attributes;
 
-	// private state
+	struct {
-
 		struct wl_listener release;
+	} WLR_PRIVATE;
 };
 
 /**
@@ -55,8 +55,7 @@ struct wlr_linux_dmabuf_v1 {
 		struct wl_signal destroy;
 	} events;
 
-	// private state
+	struct {
-
 		struct wlr_linux_dmabuf_feedback_v1_compiled *default_feedback;
 		struct wlr_drm_format_set default_formats; // for legacy clients
 		struct wl_list surfaces; // wlr_linux_dmabuf_v1_surface.link
@@ -67,6 +66,7 @@ struct wlr_linux_dmabuf_v1 {
 
 		bool (*check_dmabuf_callback)(struct wlr_dmabuf_attributes *attribs, void *data);
 		void *check_dmabuf_callback_data;
+	} WLR_PRIVATE;
 };
 
 /**

include/wlr/types/wlr_linux_drm_syncobj_v1.h

@@ -26,11 +26,11 @@ struct wlr_linux_drm_syncobj_surface_v1_state {
 struct wlr_linux_drm_syncobj_manager_v1 {
 	struct wl_global *global;
 
-	// private state
+	struct {
-
 		int drm_fd;
 
 		struct wl_listener display_destroy;
+	} WLR_PRIVATE;
 };
 
 /**

include/wlr/types/wlr_output_layer.h

@@ -50,10 +50,10 @@ struct wlr_output_layer {
 
 	void *data;
 
-	// private state
+	struct {
-
 		struct wlr_fbox src_box;
 		struct wlr_box dst_box;
+	} WLR_PRIVATE;
 };
 
 /**

include/wlr/types/wlr_output_layout.h

@@ -36,9 +36,9 @@ struct wlr_output_layout {
 
 	void *data;
 
-	// private state
+	struct {
-
 		struct wl_listener display_destroy;
+	} WLR_PRIVATE;
 };
 
 struct wlr_output_layout_output {
@@ -55,11 +55,11 @@ struct wlr_output_layout_output {
 		struct wl_signal destroy;
 	} events;
 
-	// private state
+	struct {
-
 		struct wlr_addon addon;
 
 		struct wl_listener commit;
+	} WLR_PRIVATE;
 };
 
 struct wlr_output_layout *wlr_output_layout_create(struct wl_display *display);

include/wlr/types/wlr_output_swapchain_manager.h

@@ -30,9 +30,9 @@ struct wlr_backend_output_state;
 struct wlr_output_swapchain_manager {
 	struct wlr_backend *backend;
 
-	// private state
+	struct {
-
 		struct wl_array outputs; // struct wlr_output_swapchain_manager_output
+	} WLR_PRIVATE;
 };
 
 /**

include/wlr/types/wlr_pointer_constraints_v1.h

@@ -64,13 +64,13 @@ struct wlr_pointer_constraint_v1 {
 
 	void *data;
 
-	// private state
+	struct {
-
 		struct wl_listener surface_commit;
 		struct wl_listener surface_destroy;
 		struct wl_listener seat_destroy;
 
 		struct wlr_surface_synced synced;
+	} WLR_PRIVATE;
 };
 
 struct wlr_pointer_constraints_v1 {

include/wlr/types/wlr_scene.h

@@ -75,9 +75,9 @@ struct wlr_scene_node {
 
 	struct wlr_addon_set addons;
 
-	// private state
+	struct {
-
 		pixman_region32_t visible;
+	} WLR_PRIVATE;
 };
 
 enum wlr_scene_debug_damage_option {
@@ -103,8 +103,7 @@ struct wlr_scene {
 	struct wlr_linux_dmabuf_v1 *linux_dmabuf_v1;
 	struct wlr_gamma_control_manager_v1 *gamma_control_manager_v1;
 
-	// private state
+	struct {
-
 		struct wl_listener linux_dmabuf_v1_destroy;
 		struct wl_listener gamma_control_manager_v1_destroy;
 		struct wl_listener gamma_control_manager_v1_set_gamma;
@@ -113,6 +112,7 @@ struct wlr_scene {
 		bool direct_scanout;
 		bool calculate_visibility;
 		bool highlight_transparent_region;
+	} WLR_PRIVATE;
 };
 
 /** A scene-graph node displaying a single surface. */
@@ -120,8 +120,7 @@ struct wlr_scene_surface {
 	struct wlr_scene_buffer *buffer;
 	struct wlr_surface *surface;
 
-	// private state
+	struct {
-
 		struct wlr_box clip;
 
 		struct wlr_addon addon;
@@ -133,6 +132,7 @@ struct wlr_scene_surface {
 		struct wl_listener frame_done;
 		struct wl_listener surface_destroy;
 		struct wl_listener surface_commit;
+	} WLR_PRIVATE;
 };
 
 /** A scene-graph node displaying a solid-colored rectangle */
@@ -185,8 +185,7 @@ struct wlr_scene_buffer {
 	enum wl_output_transform transform;
 	pixman_region32_t opaque_region;
 
-	// private state
+	struct {
-
 		uint64_t active_outputs;
 		struct wlr_texture *texture;
 		struct wlr_linux_dmabuf_feedback_v1_init_options prev_feedback_options;
@@ -200,6 +199,7 @@ struct wlr_scene_buffer {
 
 		struct wl_listener buffer_release;
 		struct wl_listener renderer_destroy;
+	} WLR_PRIVATE;
 };
 
 /** A viewport for an output in the scene-graph */
@@ -217,8 +217,7 @@ struct wlr_scene_output {
 		struct wl_signal destroy;
 	} events;
 
-	// private state
+	struct {
-
 		pixman_region32_t pending_commit_damage;
 
 		uint8_t index;
@@ -237,6 +236,7 @@ struct wlr_scene_output {
 
 		struct wlr_drm_syncobj_timeline *in_timeline;
 		uint64_t in_point;
+	} WLR_PRIVATE;
 };
 
 struct wlr_scene_timer {
@@ -249,12 +249,12 @@ struct wlr_scene_layer_surface_v1 {
 	struct wlr_scene_tree *tree;
 	struct wlr_layer_surface_v1 *layer_surface;
 
-	// private state
+	struct {
-
 		struct wl_listener tree_destroy;
 		struct wl_listener layer_surface_destroy;
 		struct wl_listener layer_surface_map;
 		struct wl_listener layer_surface_unmap;
+	} WLR_PRIVATE;
 };
 
 /**

include/wlr/types/wlr_security_context_v1.h

@@ -28,11 +28,11 @@ struct wlr_security_context_manager_v1 {
 
 	void *data;
 
-	// private state
+	struct {
-
 		struct wl_list contexts; // wlr_security_context_v1.link
 
 		struct wl_listener display_destroy;
+	} WLR_PRIVATE;
 };
 
 struct wlr_security_context_v1_state {

include/wlr/types/wlr_session_lock_v1.h

@@ -24,9 +24,9 @@ struct wlr_session_lock_manager_v1 {
 
 	void *data;
 
-	// private state
+	struct {
-
 		struct wl_listener display_destroy;
+	} WLR_PRIVATE;
 };
 
 struct wlr_session_lock_v1 {
@@ -42,9 +42,9 @@ struct wlr_session_lock_v1 {
 
 	void *data;
 
-	// private state
+	struct {
-
 		bool locked_sent;
+	} WLR_PRIVATE;
 };
 
 struct wlr_session_lock_surface_v1_state {
@@ -79,11 +79,11 @@ struct wlr_session_lock_surface_v1 {
 
 	void *data;
 
-	// private state
+	struct {
-
 		struct wlr_surface_synced synced;
 
 		struct wl_listener output_destroy;
+	} WLR_PRIVATE;
 };
 
 struct wlr_session_lock_manager_v1 *wlr_session_lock_manager_v1_create(

include/wlr/types/wlr_shm.h

@@ -25,12 +25,12 @@ struct wlr_renderer;
 struct wlr_shm {
 	struct wl_global *global;
 
-	// private state
+	struct {
-
 		uint32_t *formats;
 		size_t formats_len;
 
 		struct wl_listener display_destroy;
+	} WLR_PRIVATE;
 };
 
 /**

include/wlr/types/wlr_single_pixel_buffer_v1.h

@@ -14,9 +14,9 @@
 struct wlr_single_pixel_buffer_manager_v1 {
 	struct wl_global *global;
 
-	// private state
+	struct {
-
 		struct wl_listener display_destroy;
+	} WLR_PRIVATE;
 };
 
 

include/wlr/types/wlr_subcompositor.h

@@ -23,9 +23,9 @@ struct wlr_subsurface_parent_state {
 	int32_t x, y;
 	struct wl_list link;
 
-	// private state
+	struct {
-
 		struct wlr_surface_synced *synced;
+	} WLR_PRIVATE;
 };
 
 struct wlr_subsurface {
@@ -50,9 +50,9 @@ struct wlr_subsurface {
 
 	void *data;
 
-	// private state
+	struct {
-
 		struct wlr_surface_synced parent_synced;
+	} WLR_PRIVATE;
 };
 
 struct wlr_subcompositor {

include/wlr/types/wlr_tearing_control_v1.h

@@ -30,13 +30,13 @@ struct wlr_tearing_control_v1 {
 
 	struct wlr_surface *surface;
 
-	// private state
+	struct {
-
 		enum wp_tearing_control_v1_presentation_hint previous;
 		struct wlr_addon addon;
 		struct wlr_surface_synced synced;
 
 		struct wl_listener surface_commit;
+	} WLR_PRIVATE;
 };
 
 struct wlr_tearing_control_manager_v1 {

include/wlr/types/wlr_transient_seat_v1.h

@@ -17,8 +17,9 @@ struct wlr_transient_seat_v1 {
 	struct wl_resource *resource;
 	struct wlr_seat *seat;
 
-        // private state
+	struct {
 		struct wl_listener seat_destroy;
+	} WLR_PRIVATE;
 };
 
 struct wlr_transient_seat_manager_v1 {

include/wlr/types/wlr_xdg_activation_v1.h

@@ -28,14 +28,14 @@ struct wlr_xdg_activation_token_v1 {
 		struct wl_signal destroy;
 	} events;
 
-	// private state
+	struct {
-
 		char *token;
 		struct wl_resource *resource; // can be NULL
 		struct wl_event_source *timeout; // can be NULL
 
 		struct wl_listener seat_destroy;
 		struct wl_listener surface_destroy;
+	} WLR_PRIVATE;
 };
 
 struct wlr_xdg_activation_v1 {
@@ -49,13 +49,12 @@ struct wlr_xdg_activation_v1 {
 		struct wl_signal new_token; // struct wlr_xdg_activation_token_v1
 	} events;
 
-	// private state
+	struct {
-
 		struct wl_display *display;
-
 		struct wl_global *global;
 
 		struct wl_listener display_destroy;
+	} WLR_PRIVATE;
 };
 
 struct wlr_xdg_activation_v1_request_activate_event {

include/wlr/types/wlr_xdg_decoration_v1.h

@@ -54,13 +54,13 @@ struct wlr_xdg_toplevel_decoration_v1 {
 
 	void *data;
 
-	// private state
+	struct {
-
 		struct wl_listener toplevel_destroy;
 		struct wl_listener surface_configure;
 		struct wl_listener surface_ack_configure;
 
 		struct wlr_surface_synced synced;
+	} WLR_PRIVATE;
 };
 
 struct wlr_xdg_decoration_manager_v1 *

include/wlr/types/wlr_xdg_shell.h

@@ -110,9 +110,9 @@ struct wlr_xdg_popup {
 
 	struct wl_list grab_link; // wlr_xdg_popup_grab.popups
 
-	// private state
+	struct {
-
 		struct wlr_surface_synced synced;
+	} WLR_PRIVATE;
 };
 
 // each seat gets a popup grab
@@ -221,9 +221,9 @@ struct wlr_xdg_toplevel {
 		struct wl_signal set_app_id;
 	} events;
 
-	// private state
+	struct {
-
 		struct wlr_surface_synced synced;
+	} WLR_PRIVATE;
 };
 
 struct wlr_xdg_surface_configure {
@@ -304,11 +304,11 @@ struct wlr_xdg_surface {
 
 	void *data;
 
-	// private state
+	struct {
-
 		struct wlr_surface_synced synced;
 
 		struct wl_listener role_resource_destroy;
+	} WLR_PRIVATE;
 };
 
 struct wlr_xdg_toplevel_move_event {

include/wlr/util/addon.h

@@ -12,8 +12,9 @@
 #include <wayland-server-core.h>
 
 struct wlr_addon_set {
-	// private state
+	struct {
 		struct wl_list addons;
+	} WLR_PRIVATE;
 };
 
 struct wlr_addon;
@@ -26,9 +27,11 @@ struct wlr_addon_interface {
 
 struct wlr_addon {
 	const struct wlr_addon_interface *impl;
-	// private state
+
+	struct {
 		const void *owner;
 		struct wl_list link;
+	} WLR_PRIVATE;
 };
 
 void wlr_addon_set_init(struct wlr_addon_set *set);

include/wlr/xwayland/shell.h

@@ -25,13 +25,13 @@ struct wlr_xwayland_shell_v1 {
 		struct wl_signal new_surface; // struct wlr_xwayland_surface_v1
 	} events;
 
-	// private state
+	struct {
-
 		struct wl_client *client;
 		struct wl_list surfaces; // wlr_xwayland_surface_v1.link
 
 		struct wl_listener display_destroy;
 		struct wl_listener client_destroy;
+	} WLR_PRIVATE;
 };
 
 /**
@@ -41,12 +41,12 @@ struct wlr_xwayland_surface_v1 {
 	struct wlr_surface *surface;
 	uint64_t serial;
 
-	// private state
+	struct {
-
 		struct wl_resource *resource;
 		struct wl_list link;
 		struct wlr_xwayland_shell_v1 *shell;
 		bool added;
+	} WLR_PRIVATE;
 };
 
 /**

include/wlr/xwayland/xwayland.h

@@ -65,13 +65,13 @@ struct wlr_xwayland {
 
 	void *data;
 
-	// private state
+	struct {
-
 		struct wl_listener server_start;
 		struct wl_listener server_ready;
 		struct wl_listener server_destroy;
 		struct wl_listener seat_destroy;
 		struct wl_listener shell_destroy;
+	} WLR_PRIVATE;
 };
 
 enum wlr_xwayland_surface_decorations {

meson.build

@@ -22,6 +22,7 @@ big_endian = target_machine.endian() == 'big'
 add_project_arguments([
 	'-D_POSIX_C_SOURCE=200809L',
 	'-DWLR_USE_UNSTABLE',
+	'-DWLR_PRIVATE=',
 	'-DWLR_LITTLE_ENDIAN=@0@'.format(little_endian.to_int()),
 	'-DWLR_BIG_ENDIAN=@0@'.format(big_endian.to_int()),
 ], language: 'c')