Fix crash in workspace_wrap_children

When workspace_wrap_children is called on a workspace which has a
fullscreen child and the fullscreen child is a direct child of the
workspace, sway would crash.

The workspace's fullscreen pointer is unset when the fullscreen
container is detached and applied again when added to a parent, but in
this case the parent hadn't yet been added to the workspace which meant
con->workspace was NULL.

The fix makes container_handle_fullscreen_reparent return if there's no
workspace, and the fullscreen pointer is reapplied in
workspace_wrap_children.

1 files changed, 2 insertions, 1 deletions

diff --git a/sway/tree/container.c b/sway/tree/container.c
index ff10c1ab..21a0cd76 100644
--- a/sway/tree/container.c
+++ b/sway/tree/container.c
@@ -1063,7 +1063,8 @@ list_t *container_get_current_siblings(struct sway_container *container) {
 }
 
 void container_handle_fullscreen_reparent(struct sway_container *con) {
-        if (!con->is_fullscreen || con->workspace->fullscreen == con) {
+        if (!con->is_fullscreen || !con->workspace ||
+                        con->workspace->fullscreen == con) {
                 return;
         }
         if (con->workspace->fullscreen) {