backend/wayland: Add registering multiple seats

backend/wayland/backend.c

@@ -157,8 +157,8 @@ static bool backend_start(struct wlr_backend *backend) {
 
 	wl->started = true;
 
-	struct wlr_wl_seat *seat = wl->seat;
+	struct wlr_wl_seat *seat;
-	if (seat != NULL) {
+	wl_list_for_each(seat, &wl->seats, link) {
 		if (seat->keyboard) {
 			create_wl_keyboard(seat);
 		}
@@ -262,6 +262,7 @@ struct wlr_backend *wlr_wl_backend_create(struct wl_display *display,
 	wl->local_display = display;
 	wl_list_init(&wl->devices);
 	wl_list_init(&wl->outputs);
+	wl_list_init(&wl->seats);
 
 	wl->remote_display = wl_display_connect(remote);
 	if (!wl->remote_display) {

backend/wayland/output.c

@@ -586,8 +586,8 @@ struct wlr_output *wlr_wl_output_create(struct wlr_backend *wlr_backend) {
 
 	wlr_signal_emit_safe(&backend->backend.events.new_output, wlr_output);
 
-	struct wlr_wl_seat *seat = backend->seat;
+	struct wlr_wl_seat *seat;
-	if (seat != NULL) {
+	wl_list_for_each(seat, &backend->seats, link) {
 		if (seat->pointer) {
 			create_wl_pointer(seat, output);
 		}

backend/wayland/seat.c

@@ -373,7 +373,6 @@ static struct wlr_wl_input_device *get_wl_input_device_from_input_device(
 }
 
 bool create_wl_seat(struct wl_seat *wl_seat, struct wlr_wl_backend *wl) {
-	assert(!wl->seat);  // only one seat supported at the moment
 	struct wlr_wl_seat *seat = calloc(1, sizeof(struct wlr_wl_seat));
 	if (!seat) {
 		wlr_log_errno(WLR_ERROR, "Allocation failed");
@@ -381,32 +380,31 @@ bool create_wl_seat(struct wl_seat *wl_seat, struct wlr_wl_backend *wl) {
 	}
 	seat->wl_seat = wl_seat;
 	seat->backend = wl;
-	wl->seat = seat;
+	wl_list_insert(&wl->seats, &seat->link);
 	wl_seat_add_listener(wl_seat, &seat_listener, seat);
 	return true;
 }
 
 void destroy_wl_seats(struct wlr_wl_backend *wl) {
-	struct wlr_wl_seat *seat = wl->seat;
+	struct wlr_wl_seat *seat, *tmp_seat;
-	if (!seat) {
+	wl_list_for_each_safe(seat, tmp_seat, &wl->seats, link) {
-		return;
+		if (seat->touch) {
-	}
+			wl_touch_destroy(seat->touch);
-
+		}
-	if (seat->touch) {
+		if (seat->pointer) {
-		wl_touch_destroy(seat->touch);
+			wl_pointer_destroy(seat->pointer);
-	}
+		}
-	if (seat->pointer) {
+		if (seat->keyboard && !wl->started) {
-		wl_pointer_destroy(seat->pointer);
+			// early termination will not be handled by input_device_destroy
-	}
+			wl_keyboard_destroy(seat->keyboard);
-	if (seat->keyboard && !wl->started) {
+		}
-		// early termination will not be handled by input_device_destroy
+		free(seat->name);
-		wl_keyboard_destroy(seat->keyboard);
+		assert(seat->wl_seat);
-	}
-	free(seat->name);
-	if (seat->wl_seat) {
 		wl_seat_destroy(seat->wl_seat);
+
+		wl_list_remove(&seat->link);
+		free(seat);
 	}
-	free(seat);
 }
 
 static struct wlr_wl_seat *input_device_get_seat(struct wlr_input_device *wlr_dev) {

include/backend/wayland.h

@@ -39,7 +39,7 @@ struct wlr_wl_backend {
 	struct wp_presentation *presentation;
 	struct zwp_linux_dmabuf_v1 *zwp_linux_dmabuf_v1;
 	struct zwp_relative_pointer_manager_v1 *zwp_relative_pointer_manager_v1;
-	struct wlr_wl_seat *seat;
+	struct wl_list seats; // wlr_wl_seat.link
 	struct wlr_wl_pointer *current_pointer;
 	struct zwp_tablet_manager_v2 *tablet_manager;
 	struct wlr_drm_format_set linux_dmabuf_v1_formats;
@@ -109,6 +109,7 @@ struct wlr_wl_pointer {
 struct wlr_wl_seat {
 	struct wl_seat *wl_seat;
 
+	struct wl_list link; // wlr_wl_backend.seats
 	char *name;
 	struct wl_touch *touch;
 	struct wl_pointer *pointer;