view: Add view_set_output()

include/view.h

@@ -52,7 +52,7 @@ struct view {
 	 *
 	 * Many view functions (e.g. view_center(), view_fullscreen(),
 	 * view_maximize(), etc.) allow specifying a particular output
-	 * by setting view->output explicitly before calling them.
+	 * by calling view_set_output() beforehand.
 	 */
 	struct output *output;
 	struct workspace *workspace;
@@ -131,6 +131,7 @@ struct xdg_toplevel_view {
 };
 
 void view_set_activated(struct view *view);
+void view_set_output(struct view *view, struct output *output);
 void view_close(struct view *view);
 
 /**

src/view.c

@@ -111,6 +111,7 @@ static void
 view_discover_output(struct view *view)
 {
 	assert(view);
+	assert(!view->fullscreen);
 	view->output = output_nearest_to(view->server,
 		view->current.x + view->current.width / 2,
 		view->current.y + view->current.height / 2);
@@ -144,6 +145,18 @@ view_set_activated(struct view *view)
 	view->server->focused_view = view;
 }
 
+void
+view_set_output(struct view *view, struct output *output)
+{
+	assert(view);
+	assert(!view->fullscreen);
+	if (!output_is_usable(output)) {
+		wlr_log(WLR_ERROR, "invalid output set for view");
+		return;
+	}
+	view->output = output;
+}
+
 void
 view_close(struct view *view)
 {
@@ -786,6 +799,11 @@ void
 view_on_output_destroy(struct view *view)
 {
 	assert(view);
+	/*
+	 * This is the only time we modify view->output for a fullscreen
+	 * view. We expect view_adjust_for_layout_change() to be called
+	 * shortly afterward, which will exit fullscreen.
+	 */
 	view->output = NULL;
 }
 
@@ -938,7 +956,7 @@ view_snap_to_edge(struct view *view, const char *direction,
 		view_store_natural_geometry(view);
 	}
 	view_set_untiled(view);
-	view->output = output;
+	view_set_output(view, output);
 	view->tiled = edge;
 	view_apply_tiled_geometry(view);
 }

src/xdg.c

@@ -179,7 +179,7 @@ handle_request_maximize(struct wl_listener *listener, void *data)
 {
 	struct view *view = wl_container_of(listener, view, request_maximize);
 	if (!view->mapped && !view->output) {
-		view->output = output_nearest_to_cursor(view->server);
+		view_set_output(view, output_nearest_to_cursor(view->server));
 	}
 	view_maximize(view, xdg_toplevel_from_view(view)->requested.maximized,
 		/*store_natural_geometry*/ true);
@@ -191,14 +191,8 @@ set_fullscreen_from_request(struct view *view,
 {
 	if (!view->fullscreen && requested->fullscreen
 			&& requested->fullscreen_output) {
-		struct output *output = output_from_wlr_output(view->server,
+		view_set_output(view, output_from_wlr_output(view->server,
-			requested->fullscreen_output);
+			requested->fullscreen_output));
-		if (output_is_usable(output)) {
-			view->output = output;
-		} else {
-			wlr_log(WLR_ERROR,
-				"invalid output in fullscreen request");
-		}
 	}
 	view_set_fullscreen(view, requested->fullscreen);
 }
@@ -208,7 +202,7 @@ handle_request_fullscreen(struct wl_listener *listener, void *data)
 {
 	struct view *view = wl_container_of(listener, view, request_fullscreen);
 	if (!view->mapped && !view->output) {
-		view->output = output_nearest_to_cursor(view->server);
+		view_set_output(view, output_nearest_to_cursor(view->server));
 	}
 	set_fullscreen_from_request(view,
 		&xdg_toplevel_from_view(view)->requested);
@@ -315,7 +309,7 @@ position_xdg_toplevel_view(struct view *view)
 		struct view *parent = lookup_view_by_xdg_toplevel(
 			view->server, parent_xdg_toplevel);
 		assert(parent);
-		view->output = parent->output;
+		view_set_output(view, parent->output);
 		view_center(view, &parent->pending);
 	}
 }
@@ -341,7 +335,7 @@ xdg_toplevel_view_map(struct view *view)
 	}
 	view->mapped = true;
 	if (!view->output) {
-		view->output = output_nearest_to_cursor(view->server);
+		view_set_output(view, output_nearest_to_cursor(view->server));
 	}
 	struct wlr_xdg_surface *xdg_surface = xdg_surface_from_view(view);
 	view->surface = xdg_surface->surface;

src/xwayland.c

@@ -96,7 +96,7 @@ ensure_initial_geometry_and_output(struct view *view)
 		 * Just use the cursor output since we don't know yet
 		 * whether the surface position is meaningful.
 		 */
-		view->output = output_nearest_to_cursor(view->server);
+		view_set_output(view, output_nearest_to_cursor(view->server));
 	}
 }