Implement atomic layout updates for tree operations

This implements atomic layout updates for when views map, reparent or
unmap.

include/sway/desktop/transaction.h

@@ -1,5 +1,6 @@
 #ifndef _SWAY_TRANSACTION_H
 #define _SWAY_TRANSACTION_H
+#include <wlr/render/wlr_texture.h>
 #include "sway/tree/container.h"
 
 /**
@@ -48,4 +49,12 @@ void transaction_commit(struct sway_transaction *transaction);
  */
 void transaction_notify_view_ready(struct sway_view *view, uint32_t serial);
 
+/**
+ * Get the texture that should be rendered for a view.
+ *
+ * In most cases this will return the normal live texture for a view, but if the
+ * view is in a transaction then it'll return a saved texture.
+ */
+struct wlr_texture *transaction_get_texture(struct sway_view *view);
+
 #endif

include/sway/server.h

@@ -12,6 +12,7 @@
 #include <wlr/render/wlr_renderer.h>
 // TODO WLR: make Xwayland optional
 #include <wlr/xwayland.h>
+#include "list.h"
 
 struct sway_server {
 	struct wl_display *wl_display;
@@ -43,6 +44,12 @@ struct sway_server {
 
 	struct wlr_wl_shell *wl_shell;
 	struct wl_listener wl_shell_surface;
+
+	bool terminating;
+
+	// When a view is being destroyed and is waiting for a transaction to
+	// complete it will be stored here.
+	list_t *destroying_containers;
 };
 
 struct sway_server server;

include/sway/tree/container.h

@@ -65,8 +65,8 @@ struct sway_container_state {
 	double gaps_inner;
 	double gaps_outer;
 
-	//struct sway_container *parent;
-	//list_t *children;
+	struct sway_container *parent;
+	list_t *children;
 
 	// View properties
 	double view_x, view_y;
@@ -79,6 +79,10 @@ struct sway_container_state {
 	bool border_bottom;
 	bool border_left;
 	bool border_right;
+
+	// Workspace properties
+	struct sway_view *ws_fullscreen;
+	struct sway_container *ws_floating;
 };
 
 struct sway_container {
@@ -128,8 +132,6 @@ struct sway_container {
 
 	struct sway_container *parent;
 
-	list_t *marks; // list of char*
-
 	float alpha;
 
 	struct wlr_texture *title_focused;
@@ -138,6 +140,10 @@ struct sway_container {
 	struct wlr_texture *title_urgent;
 	size_t title_height;
 
+	list_t *instructions; // struct sway_transaction_instruction *
+
+	bool destroying;
+
 	struct {
 		struct wl_signal destroy;
 		// Raised after the tree updates, but before arrange_windows
@@ -181,6 +187,8 @@ 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);
+
 struct sway_container *container_destroy(struct sway_container *container);
 
 struct sway_container *container_close(struct sway_container *container);

include/sway/tree/view.h

@@ -37,7 +37,7 @@ struct sway_view_impl {
 	void (*for_each_surface)(struct sway_view *view,
 		wlr_surface_iterator_func_t iterator, void *user_data);
 	void (*close)(struct sway_view *view);
-	void (*destroy)(struct sway_view *view);
+	void (*free)(struct sway_view *view);
 };
 
 struct sway_view {
@@ -68,15 +68,10 @@ struct sway_view {
 	bool border_left;
 	bool border_right;
 
+	bool destroying;
+
 	list_t *executed_criteria; // struct criteria *
 	list_t *marks;             // char *
-	list_t *instructions;      // struct sway_transaction_instruction *
-
-	// If saved_buffer is set, the main surface of the view will render this
-	// buffer/texture instead of its own. This is used while waiting for
-	// transactions to complete.
-	struct wlr_buffer *saved_buffer;
-	int saved_surface_width, saved_surface_height;
 
 	struct wlr_texture *marks_focused;
 	struct wlr_texture *marks_focused_inactive;
@@ -244,11 +239,16 @@ void view_for_each_surface(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_map(struct sway_view *view, struct wlr_surface *wlr_surface);
 
-void view_unmap(struct sway_view *view);
+/**
+ * Unmap the view and return the surviving parent (after reaping).
+ */
+struct sway_container *view_unmap(struct sway_view *view);
 
 void view_update_position(struct sway_view *view, double lx, double ly);