Create & implement transient seat protocol

include/wlr/types/wlr_transient_seat_v1.h

@@ -0,0 +1,63 @@
+/*
+ * This an unstable interface of wlroots. No guarantees are made regarding the
+ * future consistency of this API.
+ */
+#ifndef WLR_USE_UNSTABLE
+#error "Add -DWLR_USE_UNSTABLE to enable unstable wlroots features"
+#endif
+
+#ifndef WLR_TYPES_WLR_TRANSIENT_SEAT_V1_H
+#define WLR_TYPES_WLR_TRANSIENT_SEAT_V1_H
+
+#include <wayland-server-core.h>
+
+struct wlr_seat;
+
+struct wlr_transient_seat_v1 {
+	struct wl_resource *resource;
+	struct wlr_seat *seat;
+
+        // private state
+	struct wl_listener seat_destroy;
+};
+
+struct wlr_transient_seat_manager_v1 {
+	struct wl_global *global;
+	struct wl_listener display_destroy;
+
+	struct {
+		/**
+		 * Upon receiving this signal, call
+		 * wlr_transient_seat_v1_ready() to pass a newly created seat
+		 * to the manager, or
+		 * wlr_transient_seat_v1_deny() to deny the request to create
+		 * a seat.
+		 */
+		struct wl_signal create_seat; // struct wlr_transient_seat_v1
+	} events;
+};
+
+struct wlr_transient_seat_manager_v1 *wlr_transient_seat_manager_v1_create(
+		struct wl_display *display);
+
+/**
+ * To be called when the create_seat event is received.
+ *
+ * This signals that the seat was successfully added and is ready.
+ *
+ * When the transient seat is destroyed by the client, the wlr_seat will be
+ * destroyed. The wlr_seat may also be destroyed from elsewhere, in which case
+ * the transient seat will become inert.
+ */
+void wlr_transient_seat_v1_ready(struct wlr_transient_seat_v1 *seat,
+		struct wlr_seat *wlr_seat);
+
+/**
+ * To be called when the create_seat event is received.
+ *
+ * This signals that the compositor has denied the user's request to create a
+ * transient seat.
+ */
+void wlr_transient_seat_v1_deny(struct wlr_transient_seat_v1 *seat);
+
+#endif /* WLR_TYPES_WLR_TRANSIENT_SEAT_V1_H */

protocol/meson.build

@@ -45,6 +45,7 @@ protocols = {
 	'xdg-foreign-unstable-v1': wl_protocol_dir / 'unstable/xdg-foreign/xdg-foreign-unstable-v1.xml',
 	'xdg-foreign-unstable-v2': wl_protocol_dir / 'unstable/xdg-foreign/xdg-foreign-unstable-v2.xml',
 	'xdg-output-unstable-v1': wl_protocol_dir / 'unstable/xdg-output/xdg-output-unstable-v1.xml',
+	'ext-transient-seat-v1': wl_protocol_dir / 'staging/ext-transient-seat/ext-transient-seat-v1.xml',
 
 	# Other protocols
 	'drm': 'drm.xml',

types/meson.build

@@ -79,6 +79,7 @@ wlr_files += files(
 	'wlr_tablet_tool.c',
 	'wlr_text_input_v3.c',
 	'wlr_touch.c',
+	'wlr_transient_seat_v1.c',
 	'wlr_viewporter.c',
 	'wlr_virtual_keyboard_v1.c',
 	'wlr_virtual_pointer_v1.c',

types/wlr_transient_seat_v1.c

@@ -0,0 +1,160 @@
+#include <assert.h>
+#include <stdlib.h>
+#include <wayland-util.h>
+#include <wlr/types/wlr_seat.h>
+#include <wlr/types/wlr_transient_seat_v1.h>
+#include "ext-transient-seat-v1-protocol.h"
+
+static const struct ext_transient_seat_manager_v1_interface manager_impl;
+static const struct ext_transient_seat_v1_interface transient_seat_impl;
+
+static struct wlr_transient_seat_manager_v1 *manager_from_resource(
+		struct wl_resource *resource) {
+	assert(wl_resource_instance_of(resource,
+		&ext_transient_seat_manager_v1_interface, &manager_impl));
+	return wl_resource_get_user_data(resource);
+}
+
+static struct wlr_transient_seat_v1 *transient_seat_from_resource(
+		struct wl_resource *resource) {
+	assert(wl_resource_instance_of(resource,
+		&ext_transient_seat_v1_interface, &transient_seat_impl));
+	return wl_resource_get_user_data(resource);
+}
+
+static void transient_seat_destroy(struct wlr_transient_seat_v1 *seat) {
+	wl_list_remove(&seat->seat_destroy.link);
+	wlr_seat_destroy(seat->seat);
+	free(seat);
+}
+
+static void transient_seat_handle_resource_destroy(
+		struct wl_resource *resource) {
+	struct wlr_transient_seat_v1 *seat =
+		transient_seat_from_resource(resource);
+	transient_seat_destroy(seat);
+}
+
+static void transient_seat_handle_destroy(struct wl_client *client,
+		struct wl_resource *seat_resource) {
+	wl_resource_destroy(seat_resource);
+}
+
+static const struct ext_transient_seat_v1_interface transient_seat_impl = {
+	.destroy = transient_seat_handle_destroy,
+};
+
+static void manager_create_transient_seat(struct wl_client *client,
+		struct wl_resource *manager_resource, uint32_t id) {
+	struct wlr_transient_seat_manager_v1 *manager =
+		manager_from_resource(manager_resource);
+
+	struct wlr_transient_seat_v1 *seat = calloc(1, sizeof(*seat));
+	if (!seat) {
+		goto failure;
+	}
+
+	int version = wl_resource_get_version(manager_resource);
+	seat->resource = wl_resource_create(client,
+			&ext_transient_seat_v1_interface, version, id);
+	if (!seat->resource) {
+		goto failure;
+	}
+
+	wl_resource_set_implementation(seat->resource, &transient_seat_impl,
+			seat, transient_seat_handle_resource_destroy);
+
+	wl_signal_emit_mutable(&manager->events.create_seat, seat);
+
+	return;
+
+failure:
+	free(seat);
+	wl_client_post_no_memory(client);
+}
+
+static void transient_seat_handle_seat_destroy(struct wl_listener *listener,
+		void *data) {
+	struct wlr_transient_seat_v1 *seat = wl_container_of(listener, seat,
+			seat_destroy);
+	seat->seat = NULL;
+	wl_resource_set_user_data(seat->resource, NULL);
+	transient_seat_destroy(seat);
+}
+
+void wlr_transient_seat_v1_ready(struct wlr_transient_seat_v1 *seat,
+		struct wlr_seat *wlr_seat) {
+	assert(wlr_seat);
+
+	seat->seat = wlr_seat;
+
+	seat->seat_destroy.notify = transient_seat_handle_seat_destroy;
+	wl_signal_add(&wlr_seat->events.destroy, &seat->seat_destroy);
+
+	struct wl_client *client = wl_resource_get_client(seat->resource);
+	uint32_t global_name = wl_global_get_name(seat->seat->global, client);
+	assert(global_name != 0);
+	ext_transient_seat_v1_send_ready(seat->resource, global_name);
+}
+
+void wlr_transient_seat_v1_deny(struct wlr_transient_seat_v1 *seat) {
+	ext_transient_seat_v1_send_denied(seat->resource);
+}
+
+static void manager_handle_destroy(struct wl_client *client,
+		struct wl_resource *manager_resource) {
+	wl_resource_destroy(manager_resource);
+}
+
+static const struct ext_transient_seat_manager_v1_interface manager_impl = {
+	.create = manager_create_transient_seat,
+	.destroy = manager_handle_destroy,
+};
+
+static void handle_display_destroy(struct wl_listener *listener, void *data) {
+	struct wlr_transient_seat_manager_v1 *manager =
+		wl_container_of(listener, manager, display_destroy);
+
+	wl_list_remove(&manager->display_destroy.link);
+	wl_global_destroy(manager->global);
+	free(manager);
+}
+
+static void transient_seat_manager_bind(struct wl_client *client, void *data,
+		uint32_t version, uint32_t id) {
+	struct wlr_transient_seat_manager_v1 *manager = data;
+
+	struct wl_resource *resource = wl_resource_create(client,
+		&ext_transient_seat_manager_v1_interface, version, id);
+
+	if (!resource) {
+		wl_client_post_no_memory(client);
+		return;
+	}
+
+	wl_resource_set_implementation(resource, &manager_impl, manager, NULL);
+}
+
+struct wlr_transient_seat_manager_v1 *wlr_transient_seat_manager_v1_create(
+		struct wl_display *display) {
+	struct wlr_transient_seat_manager_v1 *manager =
+		calloc(1, sizeof(*manager));
+	if (!manager) {
+		return NULL;
+	}
+
+	manager->global = wl_global_create(display,
+		&ext_transient_seat_manager_v1_interface, 1, manager,
+		transient_seat_manager_bind);
+	if (!manager->global) {
+		free(manager);
+		return NULL;
+	}
+
+	manager->display_destroy.notify = handle_display_destroy;
+	wl_display_add_destroy_listener(display, &manager->display_destroy);
+
+	wl_signal_init(&manager->events.create_seat);
+
+	return manager;
+}