Simplify transactions by utilising a dirty flag on containers

This PR changes the way we handle transactions to a more simple method.
The new method is to mark containers as dirty from low level code
(eg. arranging, or container_destroy, and eventually seat_set_focus),
then call transaction_commit_dirty which picks up those containers and
runs them through a transaction. The old methods of using transactions
(arrange_and_commit, or creating one manually) are now no longer
possible.

The highest-level code (execute_command and view implementation
handlers) will call transaction_commit_dirty, so most other code just
needs to set containers as dirty. This is done by arranging, but can
also be done by calling container_set_dirty.

5 files changed, 43 insertions, 69 deletions

diff --git a/sway/tree/arrange.c b/sway/tree/arrange.c
index bcc3ee9a..533cf71c 100644
--- a/sway/tree/arrange.c
+++ b/sway/tree/arrange.c
@@ -144,38 +144,22 @@ static void apply_tabbed_or_stacked_layout(struct sway_container *parent) {
 	}
 }
 
-/**
- * If a container has been deleted from the pending tree state, we must add it
- * to the transaction so it can be freed afterwards. To do this, we iterate the
- * server's destroying_containers list and add all of them. We may add more than
- * what we need to, but this is easy and has no negative consequences.
- */
-static void add_deleted_containers(struct sway_transaction *transaction) {
-	for (int i = 0; i < server.destroying_containers->length; ++i) {
-		struct sway_container *child = server.destroying_containers->items[i];
-		transaction_add_container(transaction, child);
-	}
-}
-
-static void arrange_children_of(struct sway_container *parent,
-		struct sway_transaction *transaction);
+static void arrange_children_of(struct sway_container *parent);
 
-static void arrange_floating(struct sway_container *floating,
-		struct sway_transaction *transaction) {
+static void arrange_floating(struct sway_container *floating) {
 	for (int i = 0; i < floating->children->length; ++i) {
 		struct sway_container *floater = floating->children->items[i];
 		if (floater->type == C_VIEW) {
 			view_autoconfigure(floater->sway_view);
 		} else {
-			arrange_children_of(floater, transaction);
+			arrange_children_of(floater);
 		}
-		transaction_add_container(transaction, floater);
+		container_set_dirty(floater);
 	}
-	transaction_add_container(transaction, floating);
+	container_set_dirty(floating);
 }
 
-static void arrange_children_of(struct sway_container *parent,
-		struct sway_transaction *transaction) {
+static void arrange_children_of(struct sway_container *parent) {
 	if (config->reloading) {
 		return;
 	}
@@ -198,7 +182,7 @@ static void arrange_children_of(struct sway_container *parent,
 		apply_horiz_layout(parent);
 		break;
 	case L_FLOATING:
-		arrange_floating(parent, transaction);
+		arrange_floating(parent);
 		break;
 	}
 
@@ -213,14 +197,13 @@ static void arrange_children_of(struct sway_container *parent,
 		if (child->type == C_VIEW) {
 			view_autoconfigure(child->sway_view);
 		} else {
-			arrange_children_of(child, transaction);
+			arrange_children_of(child);
 		}
-		transaction_add_container(transaction, child);
+		container_set_dirty(child);
 	}
 }
 
-static void arrange_workspace(struct sway_container *workspace,
-		struct sway_transaction *transaction) {
+static void arrange_workspace(struct sway_container *workspace) {
 	if (config->reloading) {
 		return;
 	}
@@ -234,15 +217,14 @@ static void arrange_workspace(struct sway_container *workspace,
 	workspace->x = output->x + area->x;
 	workspace->y = output->y + area->y;
 	add_gaps(workspace);
-	transaction_add_container(transaction, workspace);
+	container_set_dirty(workspace);
 	wlr_log(WLR_DEBUG, "Arranging workspace '%s' at %f, %f", workspace->name,
 			workspace->x, workspace->y);
-	arrange_floating(workspace->sway_workspace->floating, transaction);
-	arrange_children_of(workspace, transaction);
+	arrange_floating(workspace->sway_workspace->floating);
+	arrange_children_of(workspace);
 }
 
-static void arrange_output(struct sway_container *output,
-		struct sway_transaction *transaction) {
+static void arrange_output(struct sway_container *output) {
 	if (config->reloading) {
 		return;
 	}
@@ -253,16 +235,16 @@ static void arrange_output(struct sway_container *output,
 	output->y = output_box->y;
 	output->width = output_box->width;
 	output->height = output_box->height;
-	transaction_add_container(transaction, output);
+	container_set_dirty(output);
 	wlr_log(WLR_DEBUG, "Arranging output '%s' at %f,%f",
 			output->name, output->x, output->y);
 	for (int i = 0; i < output->children->length; ++i) {
 		struct sway_container *workspace = output->children->items[i];
-		arrange_workspace(workspace, transaction);
+		arrange_workspace(workspace);
 	}
 }
 
-static void arrange_root(struct sway_transaction *transaction) {
+static void arrange_root() {
 	if (config->reloading) {
 		return;
 	}
@@ -274,43 +256,35 @@ static void arrange_root(struct sway_transaction *transaction) {
 	root_container.y = layout_box->y;
 	root_container.width = layout_box->width;
 	root_container.height = layout_box->height;
-	transaction_add_container(transaction, &root_container);
+	container_set_dirty(&root_container);
 	for (int i = 0; i < root_container.children->length; ++i) {
 		struct sway_container *output = root_container.children->items[i];
-		arrange_output(output, transaction);
+		arrange_output(output);
 	}
 }
 
-void arrange_windows(struct sway_container *container,
-		struct sway_transaction *transaction) {
+void arrange_windows(struct sway_container *container) {
 	switch (container->type) {
 	case C_ROOT:
-		arrange_root(transaction);
+		arrange_root();
 		break;
 	case C_OUTPUT:
-		arrange_output(container, transaction);
+		arrange_output(container);
 		break;
 	case C_WORKSPACE:
-		arrange_workspace(container, transaction);
+		arrange_workspace(container);
 		break;
 	case C_CONTAINER:
-		arrange_children_of(container, transaction);
-		transaction_add_container(transaction, container);
+		arrange_children_of(container);
+		container_set_dirty(container);
 		break;
 	case C_VIEW:
 		view_autoconfigure(container->sway_view);
-		transaction_add_container(transaction, container);
+		container_set_dirty(container);
 		break;
 	case C_TYPES:
 		break;
 	}
-	add_deleted_containers(transaction);
-}
-
-void arrange_and_commit(struct sway_container *container) {
-	struct sway_transaction *transaction = transaction_create();
-	arrange_windows(container, transaction);
-	transaction_commit(transaction);
 }
 
 void remove_gaps(struct sway_container *c) {
diff --git a/sway/tree/container.c b/sway/tree/container.c
index 58852717..35f67cce 100644
--- a/sway/tree/container.c
+++ b/sway/tree/container.c
@@ -159,14 +159,6 @@ void container_free(struct sway_container *cont) {
 	wlr_texture_destroy(cont->title_focused_inactive);
 	wlr_texture_destroy(cont->title_unfocused);
 	wlr_texture_destroy(cont->title_urgent);
-
-	for (int i = 0; i < server.destroying_containers->length; ++i) {
-		if (server.destroying_containers->items[i] == cont) {
-			list_del(server.destroying_containers, i);
-			break;
-		}
-	}
-
 	list_free(cont->instructions);
 	list_free(cont->children);
 	list_free(cont->current.children);
@@ -325,7 +317,7 @@ static struct sway_container *container_destroy_noreaping(
 	}
 
 	con->destroying = true;
-	list_add(server.destroying_containers, con);
+	container_set_dirty(con);
 
 	if (!con->parent) {
 		return NULL;
@@ -1069,9 +1061,15 @@ void container_floating_move_to(struct sway_container *con,
 	if (old_workspace != new_workspace) {
 		container_remove_child(con);
 		container_add_child(new_workspace->sway_workspace->floating, con);
-		struct sway_transaction *transaction = transaction_create();
-		arrange_windows(old_workspace, transaction);
-		arrange_windows(new_workspace, transaction);
-		transaction_commit(transaction);
+		arrange_windows(old_workspace);
+		arrange_windows(new_workspace);
+	}
+}
+
+void container_set_dirty(struct sway_container *container) {
+	if (container->dirty) {
+		return;
 	}
+	container->dirty = true;
+	list_add(server.dirty_containers, container);
 }
diff --git a/sway/tree/layout.c b/sway/tree/layout.c
index ba234e89..54ddb3f9 100644
--- a/sway/tree/layout.c
+++ b/sway/tree/layout.c
@@ -22,7 +22,8 @@ struct sway_container root_container;
 
 static void output_layout_handle_change(struct wl_listener *listener,
 		void *data) {
-	arrange_and_commit(&root_container);
+	arrange_windows(&root_container);
+	transaction_commit_dirty();
 }
 
 void layout_init(void) {
diff --git a/sway/tree/view.c b/sway/tree/view.c
index b356183c..bf380d98 100644
--- a/sway/tree/view.c
+++ b/sway/tree/view.c
@@ -594,11 +594,12 @@ void view_unmap(struct sway_view *view) {
 		ws->sway_workspace->fullscreen = NULL;
 		container_destroy(view->swayc);
 
-		arrange_and_commit(ws->parent);
+		arrange_windows(ws->parent);
 	} else {
 		struct sway_container *parent = container_destroy(view->swayc);
-		arrange_and_commit(parent);
+		arrange_windows(parent);
 	}
+	transaction_commit_dirty();
 	view->surface = NULL;
 }
 
diff --git a/sway/tree/workspace.c b/sway/tree/workspace.c
index 50f9400a..2a2d834a 100644
--- a/sway/tree/workspace.c
+++ b/sway/tree/workspace.c
@@ -427,7 +427,7 @@ bool workspace_switch(struct sway_container *workspace) {
 	}
 	seat_set_focus(seat, next);
 	struct sway_container *output = container_parent(workspace, C_OUTPUT);
-	arrange_and_commit(output);
+	arrange_windows(output);
 	return true;
 }