Refactor destroy functions and save workspaces when there's no outputs

This changes the destroy functions to the following:

* output_begin_destroy
* output_destroy
* workspace_begin_destroy
* workspace_destroy
* container_begin_destroy
* container_destroy
* view_begin_destroy
* view_destroy

The terminology was `destroy` and `free`, and it has been changed to
`begin_destroy` and `destroy` respectively.

When the last output is disconnected, its workspaces will now be stashed
in the root. Upon connection of a new output they will be restored.

There is a new function `workspace_consider_destroy` which decides
whether the given workspace should be destroyed or not (ie. empty and
not visible).

Calling container_begin_destroy will no longer automatically reap the
parents. In some places we want to reap the parents and in some we
don't, so this is left to the caller.

container_reap_empty_recursive and container_reap_empty have been
combined into one function and it will recurse up the tree.

1 files changed, 6 insertions, 4 deletions

diff --git a/sway/tree/view.c b/sway/tree/view.c
index 7bf7325a..ba4a880f 100644
--- a/sway/tree/view.c
+++ b/sway/tree/view.c
@@ -35,7 +35,7 @@ void view_init(struct sway_view *view, enum sway_view_type type,
         wl_signal_init(&view->events.unmap);
 }
 
-void view_free(struct sway_view *view) {
+void view_destroy(struct sway_view *view) {
         if (!sway_assert(view->surface == NULL, "Tried to free mapped view")) {
                 return;
         }
@@ -75,14 +75,14 @@ void view_free(struct sway_view *view) {
  * destroying flag will make the view get freed when the transaction is
  * finished.
  */
-void view_destroy(struct sway_view *view) {
+void view_begin_destroy(struct sway_view *view) {
         if (!sway_assert(view->surface == NULL, "Tried to destroy a mapped view")) {
                 return;
         }
         view->destroying = true;
 
         if (!view->swayc) {
-                view_free(view);
+                view_destroy(view);
         }
 }
 
@@ -560,7 +560,9 @@ void view_unmap(struct sway_view *view) {
         }
 
         bool was_fullscreen = view->swayc->is_fullscreen;
-        struct sway_container *surviving_ancestor = container_destroy(view->swayc);
+        struct sway_container *parent = view->swayc->parent;
+        container_begin_destroy(view->swayc);
+        struct sway_container *surviving_ancestor = container_reap_empty(parent);
 
         // If the workspace wasn't reaped
         if (surviving_ancestor && surviving_ancestor->type >= C_WORKSPACE) {