Fix scratchpad fullscreen behavior and crash

When setting fullscreen on a hidden scratchpad container, there was a
check to see if there was an existing fullscreen container on the
workspace so it could be fullscreen disabled first. Since the workspace
is NULL, it would cause a SIGSEGV. This adds a NULL check to avoid the
crash.

This also changes the behavior of how fullscreen is handled when adding
a container to the scratchpad or changing visibility of a scratchpad
container to match i3's. The behavior is as follows:
- When adding a container to the scratchpad or hiding a container back
  into the scratchpad, there is an implicit fullscreen disable
- When setting fullscreen on a container that is hidden in the
  scratchpad, it will be fullscreen when shown (and fullscreen disabled
  when hidden as stated above)
- When setting fullscreen global on a container that is hidden in the
  scratchpad, it will be shown immediately as fullscreen global. The
  container is not moved to a workspace and remains in the
  scratchpad. The container will be visible until fullscreen disabled
  or killed. Since the container is in the scratchpad, running
  `scratchpad show` or `move container to scratchpad` will have no
  effect

This also changes `container_replace` to transfer fullscreen and
scratchpad status.

1 files changed, 14 insertions, 0 deletions

diff --git a/sway/tree/root.c b/sway/tree/root.c
index a9d306a4..1dabc287 100644
--- a/sway/tree/root.c
+++ b/sway/tree/root.c
@@ -62,6 +62,11 @@ void root_scratchpad_add_container(struct sway_container *con) {
         struct sway_container *parent = con->parent;
         struct sway_workspace *workspace = con->workspace;
 
+        // Clear the fullscreen mode when sending to the scratchpad
+        if (con->fullscreen_mode != FULLSCREEN_NONE) {
+                container_fullscreen_disable(con);
+        }
+
         // When a tiled window is sent to scratchpad, center and resize it.
         if (!container_is_floating(con)) {
                 container_set_floating(con, true);
@@ -143,6 +148,15 @@ void root_scratchpad_hide(struct sway_container *con) {
         struct sway_node *focus = seat_get_focus_inactive(seat, &root->node);
         struct sway_workspace *ws = con->workspace;
 
+        if (con->fullscreen_mode == FULLSCREEN_GLOBAL && !con->workspace) {
+                // If the container was made fullscreen global while in the scratchpad,
+                // it should be shown until fullscreen has been disabled
+                return;
+        }
+
+        if (con->fullscreen_mode != FULLSCREEN_NONE) {
+                container_fullscreen_disable(con);
+        }
         container_detach(con);
         arrange_workspace(ws);
         if (&con->node == focus || node_has_ancestor(focus, &con->node)) {