From 12a37d666c49b194b542a5092bac3087ab2d9358 Mon Sep 17 00:00:00 2001
From: emersion <contact@emersion.fr>
Date: Sat, 19 May 2018 17:12:01 +0100
Subject: [PATCH] xwayland: listen for wlr_drag destroy

---
 include/xwayland/xwm.h   |  2 ++
 xwayland/selection/dnd.c | 66 +++++++++++++++++++++-------------------
 2 files changed, 36 insertions(+), 32 deletions(-)

diff --git a/include/xwayland/xwm.h b/include/xwayland/xwm.h
index 43ef718c3..9bb9a4268 100644
--- a/include/xwayland/xwm.h
+++ b/include/xwayland/xwm.h
@@ -117,6 +117,7 @@ struct wlr_xwm {
 	struct wl_list unpaired_surfaces; // wlr_xwayland_surface::unpaired_link
 
 	struct wlr_drag *incoming_drag;
+
 	struct wlr_drag *drag;
 	struct wlr_xwayland_surface *drag_focus;
 
@@ -135,6 +136,7 @@ struct wlr_xwm {
 	struct wl_listener seat_drag_drop;
 	struct wl_listener seat_drag_destroy;
 	struct wl_listener seat_drag_source_destroy;
+	struct wl_listener incoming_drag_destroy;
 };
 
 struct wlr_xwm *xwm_create(struct wlr_xwayland *wlr_xwayland);
diff --git a/xwayland/selection/dnd.c b/xwayland/selection/dnd.c
index 6e648c5bc..183ae67aa 100644
--- a/xwayland/selection/dnd.c
+++ b/xwayland/selection/dnd.c
@@ -320,6 +320,19 @@ error:
 	return false;
 }
 
+static void incoming_drag_handle_destroy(struct wl_listener *listener,
+		void *data) {
+	struct wlr_xwm *xwm = wl_container_of(listener, xwm, incoming_drag_destroy);
+
+	static const uint32_t values[] = { XCB_STACK_MODE_BELOW };
+	xcb_configure_window(xwm->xcb_conn, xwm->dnd_window,
+		XCB_CONFIG_WINDOW_STACK_MODE, values);
+	xcb_unmap_window(xwm->xcb_conn, xwm->dnd_window);
+
+	wl_list_remove(&xwm->incoming_drag_destroy.link);
+	xwm->incoming_drag = NULL;
+}
+
 /**
  * Handle an enter message for an incoming DnD operation.
  */
@@ -339,18 +352,19 @@ static void xwm_handle_dnd_enter(struct wlr_xwm *xwm,
 		return;
 	}
 
-	if (xwm->incoming_drag == NULL) {
+	if (xwm->incoming_drag != NULL) {
 		wlr_log(L_DEBUG, "ignoring XdndEnter client message because "
-			"no xwayland drag is being performed");
+			"another xwayland drag is being performed");
 		return;
 	}
 
-	struct wlr_xwayland_data_source *source =
-		xwayland_data_source_from_wlr_data_source(xwm->incoming_drag->source);
+	struct wlr_seat *seat = xwm->seat;
+	struct wlr_seat_client *seat_client =
+		wlr_seat_client_for_wl_client(seat, xwm->xwayland->client);
 
-	if (source->base.mime_types.size > 0) {
-		wlr_log(L_DEBUG, "ignoring XdndEnter client message because "
-			"it has already been received");
+	struct wlr_xwayland_data_source *source =
+		xwayland_data_source_create(&xwm->dnd_selection);
+	if (source == NULL) {
 		return;
 	}
 
@@ -374,6 +388,17 @@ static void xwm_handle_dnd_enter(struct wlr_xwm *xwm,
 		}
 	}
 
+	// TODO: set the icon?
+	xwm->incoming_drag =
+		wlr_seat_client_start_grab(seat_client, &source->base, NULL, NULL);
+	if (xwm->incoming_drag == NULL) {
+		wlr_log(L_ERROR, "could not start grab");
+	}
+
+	wl_signal_add(&xwm->incoming_drag->events.destroy,
+		&xwm->incoming_drag_destroy);
+	xwm->incoming_drag_destroy.notify = incoming_drag_handle_destroy;
+
 	wlr_log(L_DEBUG, "DND_ENTER window=%d", source_window);
 }
 
@@ -399,7 +424,7 @@ static void xwm_handle_dnd_position(struct wlr_xwm *xwm,
 	}
 
 	if (xwm->incoming_drag == NULL) {
-		wlr_log(L_DEBUG, "ignoring XdndEnter client message because "
+		wlr_log(L_DEBUG, "ignoring XdndPosition client message because "
 			"no xwayland drag is being performed");
 		return;
 	}
@@ -453,32 +478,9 @@ int xwm_dnd_handle_xfixes_selection_notify(struct wlr_xwm *xwm,
 		xcb_configure_window(xwm->xcb_conn, xwm->dnd_window,
 			XCB_CONFIG_WINDOW_STACK_MODE, values);
 
-		struct wlr_seat *seat = selection->xwm->seat;
-		struct wlr_seat_client *seat_client = wlr_seat_client_for_wl_client(
-			seat, selection->xwm->xwayland->client);
-
-		struct wlr_xwayland_data_source *source =
-			xwayland_data_source_create(selection);
-		if (source == NULL) {
-			return 0;
-		}
-
-		// TODO: send motion events to DND window
-		selection->xwm->incoming_drag =
-			wlr_seat_client_start_grab(seat_client, &source->base, NULL, NULL);
-		if (selection->xwm->incoming_drag == NULL) {
-			wlr_log(L_ERROR, "could not start grab");
-		}
+		// Let's wait for the DND_ENTER message
 	} else {
 		wlr_log(L_INFO, "end grab");
-
-		static const uint32_t values[] = { XCB_STACK_MODE_BELOW };
-		xcb_configure_window(xwm->xcb_conn, xwm->dnd_window,
-			XCB_CONFIG_WINDOW_STACK_MODE, values);
-		xcb_unmap_window(xwm->xcb_conn, xwm->dnd_window);
-
-		// TODO: drag_end(selection->xwm->incoming_drag)
-		selection->xwm->incoming_drag = NULL;
 	}
 
 	return 1;