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.

5 files changed, 21 insertions, 29 deletions

diff --git a/include/sway/output.h b/include/sway/output.h
index d0d034b3..098540fb 100644
--- a/include/sway/output.h
+++ b/include/sway/output.h
@@ -39,6 +39,12 @@ struct sway_output {
         } events;
 };
 
+struct sway_container *output_create(struct sway_output *sway_output);
+
+void output_destroy(struct sway_container *output);
+
+void output_begin_destroy(struct sway_container *output);
+
 typedef void (*sway_surface_iterator_func_t)(struct sway_output *output,
         struct wlr_surface *surface, struct wlr_box *box, float rotation,
         void *user_data);
diff --git a/include/sway/tree/container.h b/include/sway/tree/container.h
index cd886cd0..2cb23d3c 100644
--- a/include/sway/tree/container.h
+++ b/include/sway/tree/container.h
@@ -176,27 +176,6 @@ struct sway_container *container_create(enum sway_container_type type);
 
 const char *container_type_to_str(enum sway_container_type type);
 
-struct sway_container *output_create(struct sway_output *sway_output);
-
-/**
- * Create a new container container. A container container can be a a child of
- * a workspace container or another container container.
- */
-struct sway_container *container_container_create();
-
-/**
- * Create a new output. Outputs are children of the root container and have no
- * order in the tree structure.
- */
-struct sway_container *output_create(struct sway_output *sway_output);
-
-/**
- * Create a new workspace container. Workspaces are children of an output
- * container and are ordered alphabetically by name.
- */
-struct sway_container *workspace_create(struct sway_container *output,
-                const char *name);
-
 /*
  * Create a new view container. A view can be a child of a workspace container
  * or a container container and are rendered in the order and structure of
@@ -205,9 +184,9 @@ struct sway_container *workspace_create(struct sway_container *output,
 struct sway_container *container_view_create(
                 struct sway_container *sibling, struct sway_view *sway_view);
 
-void container_free(struct sway_container *cont);
+void container_destroy(struct sway_container *con);
 
-struct sway_container *container_destroy(struct sway_container *container);
+void container_begin_destroy(struct sway_container *con);
 
 struct sway_container *container_close(struct sway_container *container);
 
@@ -255,10 +234,7 @@ void container_update_textures_recursive(struct sway_container *con);
 
 void container_damage_whole(struct sway_container *container);
 
-bool container_reap_empty(struct sway_container *con);
-
-struct sway_container *container_reap_empty_recursive(
-                struct sway_container *con);
+struct sway_container *container_reap_empty(struct sway_container *con);
 
 struct sway_container *container_flatten(struct sway_container *container);
 
diff --git a/include/sway/tree/root.h b/include/sway/tree/root.h
index d1f04a96..ee4bd836 100644
--- a/include/sway/tree/root.h
+++ b/include/sway/tree/root.h
@@ -24,6 +24,7 @@ struct sway_root {
         struct wl_list outputs; // sway_output::link
 
         list_t *scratchpad; // struct sway_container
+        list_t *saved_workspaces; // For when there's no connected outputs
 
         struct {
                 struct wl_signal new_container;
diff --git a/include/sway/tree/view.h b/include/sway/tree/view.h
index 5fdecc2b..f73ce571 100644
--- a/include/sway/tree/view.h
+++ b/include/sway/tree/view.h
@@ -284,10 +284,10 @@ void view_for_each_popup(struct sway_view *view,
 void view_init(struct sway_view *view, enum sway_view_type type,
         const struct sway_view_impl *impl);
 
-void view_free(struct sway_view *view);
-
 void view_destroy(struct sway_view *view);
 
+void view_begin_destroy(struct sway_view *view);
+
 void view_map(struct sway_view *view, struct wlr_surface *wlr_surface);
 
 void view_unmap(struct sway_view *view);
diff --git a/include/sway/tree/workspace.h b/include/sway/tree/workspace.h
index 35c91017..efcb7c69 100644
--- a/include/sway/tree/workspace.h
+++ b/include/sway/tree/workspace.h
@@ -18,6 +18,15 @@ extern char *prev_workspace_name;
 
 struct sway_container *workspace_get_initial_output(const char *name);
 
+struct sway_container *workspace_create(struct sway_container *output,
+                const char *name);
+
+void workspace_destroy(struct sway_container *workspace);
+
+void workspace_begin_destroy(struct sway_container *workspace);
+
+void workspace_consider_destroy(struct sway_container *ws);
+
 char *workspace_next_name(const char *output_name);
 
 bool workspace_switch(struct sway_container *workspace,