From faa00a4a3362a8d7ea3942be50f95eb693fddb2e Mon Sep 17 00:00:00 2001
From: emersion <contact@emersion.fr>
Date: Wed, 30 Jan 2019 14:07:59 +0100
Subject: [PATCH] rootston: only allow one drag icon per seat

---
 include/rootston/seat.h |  3 +--
 rootston/cursor.c       |  5 ++---
 rootston/output.c       | 15 +++++++--------
 rootston/seat.c         |  8 +++++---
 4 files changed, 15 insertions(+), 16 deletions(-)

diff --git a/include/rootston/seat.h b/include/rootston/seat.h
index 4667cd38..a91d8481 100644
--- a/include/rootston/seat.h
+++ b/include/rootston/seat.h
@@ -29,7 +29,7 @@ struct roots_seat {
 	struct wl_list views; // roots_seat_view::link
 	bool has_focus;
 
-	struct wl_list drag_icons; // roots_drag_icon::link
+	struct roots_drag_icon *drag_icon; // can be NULL
 
 	struct wl_list keyboards;
 	struct wl_list pointers;
@@ -61,7 +61,6 @@ struct roots_seat_view {
 struct roots_drag_icon {
 	struct roots_seat *seat;
 	struct wlr_drag_icon *wlr_drag_icon;
-	struct wl_list link;
 
 	double x, y;
 
diff --git a/rootston/cursor.c b/rootston/cursor.c
index 838f5d78..6e09c06e 100644
--- a/rootston/cursor.c
+++ b/rootston/cursor.c
@@ -151,9 +151,8 @@ static void roots_passthrough_cursor(struct roots_cursor *cursor,
 		wlr_seat_pointer_clear_focus(seat->seat);
 	}
 
-	struct roots_drag_icon *drag_icon;
-	wl_list_for_each(drag_icon, &seat->drag_icons, link) {
-		roots_drag_icon_update_position(drag_icon);
+	if (seat->drag_icon != NULL) {
+		roots_drag_icon_update_position(seat->drag_icon);
 	}
 }
 
diff --git a/rootston/output.c b/rootston/output.c
index df8328dd..3aad1c06 100644
--- a/rootston/output.c
+++ b/rootston/output.c
@@ -120,15 +120,14 @@ static void drag_icons_for_each_surface(struct roots_input *input,
 		void *user_data) {
 	struct roots_seat *seat;
 	wl_list_for_each(seat, &input->seats, link) {
-		struct roots_drag_icon *drag_icon;
-		wl_list_for_each(drag_icon, &seat->drag_icons, link) {
-			if (!drag_icon->wlr_drag_icon->mapped) {
-				continue;
-			}
-			surface_for_each_surface(drag_icon->wlr_drag_icon->surface,
-				drag_icon->x, drag_icon->y, 0, layout_data,
-				iterator, user_data);
+		struct roots_drag_icon *drag_icon = seat->drag_icon;
+		if (drag_icon == NULL || !drag_icon->wlr_drag_icon->mapped) {
+			continue;
 		}
+
+		surface_for_each_surface(drag_icon->wlr_drag_icon->surface,
+			drag_icon->x, drag_icon->y, 0, layout_data,
+			iterator, user_data);
 	}
 }
 
diff --git a/rootston/seat.c b/rootston/seat.c
index a6281f50..cd95472d 100644
--- a/rootston/seat.c
+++ b/rootston/seat.c
@@ -594,7 +594,9 @@ static void roots_drag_icon_handle_destroy(struct wl_listener *listener,
 		wl_container_of(listener, icon, destroy);
 	roots_drag_icon_damage_whole(icon);
 
-	wl_list_remove(&icon->link);
+	assert(icon->seat->drag_icon == icon);
+	icon->seat->drag_icon = NULL;
+
 	wl_list_remove(&icon->surface_commit.link);
 	wl_list_remove(&icon->unmap.link);
 	wl_list_remove(&icon->destroy.link);
@@ -622,7 +624,8 @@ static void roots_seat_handle_new_drag_icon(struct wl_listener *listener,
 	icon->destroy.notify = roots_drag_icon_handle_destroy;
 	wl_signal_add(&wlr_drag_icon->events.destroy, &icon->destroy);
 
-	wl_list_insert(&seat->drag_icons, &icon->link);
+	assert(seat->drag_icon == NULL);
+	seat->drag_icon = icon;
 
 	roots_drag_icon_update_position(icon);
 }
@@ -706,7 +709,6 @@ struct roots_seat *roots_seat_create(struct roots_input *input, char *name) {
 	wl_list_init(&seat->tablet_pads);
 	wl_list_init(&seat->switches);
 	wl_list_init(&seat->views);
-	wl_list_init(&seat->drag_icons);
 
 	seat->input = input;