Implement type safe arguments and demote sway_container

This commit changes the meaning of sway_container so that it only refers
to layout containers and view containers. Workspaces, outputs and the
root are no longer known as containers. Instead, root, outputs,
workspaces and containers are all a type of node, and containers come in
two types: layout containers and view containers.

In addition to the above, this implements type safe variables. This
means we use specific types such as sway_output and sway_workspace
instead of generic containers or nodes. However, it's worth noting that
in a few places places (eg. seat focus and transactions) referring to
them in a generic way is unavoidable which is why we still use nodes in
some places.

If you want a TL;DR, look at node.h, as well as the struct definitions
for root, output, workspace and container. Note that sway_output now
contains a workspaces list, and workspaces now contain a tiling and
floating list, and containers now contain a pointer back to the
workspace.

There are now functions for seat_get_focused_workspace and
seat_get_focused_container. The latter will return NULL if a workspace
itself is focused. Most other seat functions like seat_get_focus and
seat_set_focus now accept and return nodes.

In the config->handler_context struct, current_container has been
replaced with three pointers: node, container and workspace. node is the
same as what current_container was, while workspace is the workspace
that the node resides on and container is the actual container, which
may be NULL if a workspace itself is focused.

The global root_container variable has been replaced with one simply
called root, which is a pointer to the sway_root instance.

The way outputs are created, enabled, disabled and destroyed has
changed. Previously we'd wrap the sway_output in a container when it is
enabled, but as we don't have containers any more it needs a different
approach. The output_create and output_destroy functions previously
created/destroyed the container, but now they create/destroy the
sway_output. There is a new function output_disable to disable an output
without destroying it.

Containers have a new view property. If this is populated then the
container is a view container, otherwise it's a layout container. Like
before, this property is immutable for the life of the container.

Containers have both a `sway_container *parent` and
`sway_workspace *workspace`. As we use specific types now, parent cannot
point to a workspace so it'll be NULL for containers which are direct
children of the workspace. The workspace property is set for all
containers, except those which are hidden in the scratchpad as they have
no workspace.

In some cases we need to refer to workspaces in a container-like way.
For example, workspaces have layout and children, but when using
specific types this makes it difficult. Likewise, it's difficult for a
container to get its parent's layout when the parent could be another
container or a workspace. To make it easier, some helper functions have
been created: container_parent_layout and container_get_siblings.

container_remove_child has been renamed to container_detach and
container_replace_child has been renamed to container_replace.

`container_handle_fullscreen_reparent(con, old_parent)` has had the
old_parent removed. We now unfullscreen the workspace when detaching the
container, so this function is simplified and only needs one argument
now.

container_notify_subtree_changed has been renamed to
container_update_representation. This is more descriptive of its
purpose. I also wanted to be able to call it with whatever container was
changed rather than the container's parent, which makes bubbling up to
the workspace easier.

There are now state structs per node thing. ie. sway_output_state,
sway_workspace_state and sway_container_state.

The focus, move and layout commands have been completely refactored to
work with the specific types. I considered making these a separate PR,
but I'd be backporting my changes only to replace them again, and it's
easier just to test everything at once.

sway/desktop/output.c

@@ -28,10 +28,10 @@
 #include "sway/tree/view.h"
 #include "sway/tree/workspace.h"
 
-struct sway_container *output_by_name(const char *name) {
-	for (int i = 0; i < root_container.children->length; ++i) {
-		struct sway_container *output = root_container.children->items[i];
-		if (strcasecmp(output->name, name) == 0) {
+struct sway_output *output_by_name(const char *name) {
+	for (int i = 0; i < root->outputs->length; ++i) {
+		struct sway_output *output = root->outputs->items[i];
+		if (strcasecmp(output->wlr_output->name, name) == 0) {
 			return output;
 		}
 	}
@@ -98,8 +98,8 @@ static bool get_surface_box(struct surface_iterator_data *data,
 	wlr_box_rotated_bounds(&box, data->rotation, &rotated_box);
 
 	struct wlr_box output_box = {
-		.width = output->swayc->current.swayc_width,
-		.height = output->swayc->current.swayc_height,
+		.width = output->wlr_output->width,
+		.height = output->wlr_output->height,
 	};
 
 	struct wlr_box intersection;
@@ -145,12 +145,12 @@ void output_view_for_each_surface(struct sway_output *output,
 		.user_iterator = iterator,
 		.user_data = user_data,
 		.output = output,
-		.ox = view->swayc->current.view_x - output->swayc->current.swayc_x
+		.ox = view->container->current.view_x - output->wlr_output->lx
 			- view->geometry.x,
-		.oy = view->swayc->current.view_y - output->swayc->current.swayc_y
+		.oy = view->container->current.view_y - output->wlr_output->ly
 			- view->geometry.y,
-		.width = view->swayc->current.view_width,
-		.height = view->swayc->current.view_height,
+		.width = view->container->current.view_width,
+		.height = view->container->current.view_height,
 		.rotation = 0, // TODO
 	};
 
@@ -164,12 +164,12 @@ void output_view_for_each_popup(struct sway_output *output,
 		.user_iterator = iterator,
 		.user_data = user_data,
 		.output = output,
-		.ox = view->swayc->current.view_x - output->swayc->current.swayc_x
+		.ox = view->container->current.view_x - output->wlr_output->lx
 			- view->geometry.x,
-		.oy = view->swayc->current.view_y - output->swayc->current.swayc_y
+		.oy = view->container->current.view_y - output->wlr_output->ly
 			- view->geometry.y,
-		.width = view->swayc->current.view_width,
-		.height = view->swayc->current.view_height,
+		.width = view->container->current.view_width,
+		.height = view->container->current.view_height,
 		.rotation = 0, // TODO
 	};
 
@@ -197,8 +197,8 @@ void output_unmanaged_for_each_surface(struct sway_output *output,
 	wl_list_for_each(unmanaged_surface, unmanaged, link) {
 		struct wlr_xwayland_surface *xsurface =
 			unmanaged_surface->wlr_xwayland_surface;
-		double ox = unmanaged_surface->lx - output->swayc->current.swayc_x;
-		double oy = unmanaged_surface->ly - output->swayc->current.swayc_y;
+		double ox = unmanaged_surface->lx - output->wlr_output->lx;
+		double oy = unmanaged_surface->ly - output->wlr_output->ly;
 
 		output_surface_for_each_surface(output, xsurface->surface, ox, oy,
 			iterator, user_data);
@@ -211,8 +211,8 @@ void output_drag_icons_for_each_surface(struct sway_output *output,
 		void *user_data) {
 	struct sway_drag_icon *drag_icon;
 	wl_list_for_each(drag_icon, drag_icons, link) {
-		double ox = drag_icon->x - output->swayc->x;
-		double oy = drag_icon->y - output->swayc->y;
+		double ox = drag_icon->x - output->wlr_output->lx;
+		double oy = drag_icon->y - output->wlr_output->ly;
 
 		if (drag_icon->wlr_drag_icon->mapped) {
 			output_surface_for_each_surface(output,
@@ -229,19 +229,13 @@ static void scale_box(struct wlr_box *box, float scale) {
 	box->height *= scale;
 }
 
-struct sway_container *output_get_active_workspace(struct sway_output *output) {
+struct sway_workspace *output_get_active_workspace(struct sway_output *output) {
 	struct sway_seat *seat = input_manager_current_seat(input_manager);
-	struct sway_container *focus =
-		seat_get_focus_inactive(seat, output->swayc);
+	struct sway_node *focus = seat_get_active_child(seat, &output->node);
 	if (!focus) {
-		// We've never been to this output before
-		focus = output->swayc->current.children->items[0];
+		return output->workspaces->items[0];
 	}
-	struct sway_container *workspace = focus;
-	if (workspace->type != C_WORKSPACE) {
-		workspace = container_parent(workspace, C_WORKSPACE);
-	}
-	return workspace;
+	return focus->sway_workspace;
 }
 
 bool output_has_opaque_overlay_layer_surface(struct sway_output *output) {
@@ -255,8 +249,8 @@ bool output_has_opaque_overlay_layer_surface(struct sway_output *output) {
 		struct sway_layer_surface *sway_layer_surface =
 			layer_from_wlr_layer_surface(wlr_layer_surface);
 		pixman_box32_t output_box = {
-			.x2 = output->swayc->current.swayc_width,
-			.y2 = output->swayc->current.swayc_height,
+			.x2 = output->wlr_output->width,
+			.y2 = output->wlr_output->height,
 		};
 		pixman_region32_t surface_opaque_box;
 		pixman_region32_init(&surface_opaque_box);
@@ -307,15 +301,15 @@ struct send_frame_done_data {
 
 static void send_frame_done_container_iterator(struct sway_container *con,
 		void *_data) {
-	if (con->type != C_VIEW) {
+	if (!con->view) {
 		return;
 	}
-	if (!view_is_visible(con->sway_view)) {
+	if (!view_is_visible(con->view)) {
 		return;
 	}
 
 	struct send_frame_done_data *data = _data;
-	output_view_for_each_surface(data->output, con->sway_view,
+	output_view_for_each_surface(data->output, con->view,
 		send_frame_done_iterator, data->when);
 }
 
@@ -328,15 +322,14 @@ static void send_frame_done(struct sway_output *output, struct timespec *when) {
 		.output = output,
 		.when = when,
 	};
-	struct sway_container *workspace = output_get_active_workspace(output);
-	if (workspace->current.ws_fullscreen) {
+	struct sway_workspace *workspace = output_get_active_workspace(output);
+	if (workspace->current.fullscreen) {
 		send_frame_done_container_iterator(
-				workspace->current.ws_fullscreen, &data);
-		container_for_each_child(workspace->current.ws_fullscreen,
+				workspace->current.fullscreen, &data);
+		container_for_each_child(workspace->current.fullscreen,
 				send_frame_done_container_iterator, &data);
 #ifdef HAVE_XWAYLAND
-		send_frame_done_unmanaged(output,
-			&root_container.sway_root->xwayland_unmanaged, when);
+		send_frame_done_unmanaged(output, &root->xwayland_unmanaged, when);
 #endif
 	} else {
 		send_frame_done_layer(output,
@@ -348,8 +341,7 @@ static void send_frame_done(struct sway_output *output, struct timespec *when) {
 				send_frame_done_container_iterator, &data);
 
 #ifdef HAVE_XWAYLAND
-		send_frame_done_unmanaged(output,
-			&root_container.sway_root->xwayland_unmanaged, when);
+		send_frame_done_unmanaged(output, &root->xwayland_unmanaged, when);
 #endif
 		send_frame_done_layer(output,
 			&output->layers[ZWLR_LAYER_SHELL_V1_LAYER_TOP], when);
@@ -358,8 +350,7 @@ static void send_frame_done(struct sway_output *output, struct timespec *when) {
 send_frame_overlay:
 	send_frame_done_layer(output,
 		&output->layers[ZWLR_LAYER_SHELL_V1_LAYER_OVERLAY], when);
-	send_frame_done_drag_icons(output, &root_container.sway_root->drag_icons,
-		when);
+	send_frame_done_drag_icons(output, &root->drag_icons, when);
 }
 
 static void damage_handle_frame(struct wl_listener *listener, void *data) {
@@ -391,7 +382,11 @@ static void damage_handle_frame(struct wl_listener *listener, void *data) {
 }
 
 void output_damage_whole(struct sway_output *output) {
-	wlr_output_damage_add_whole(output->damage);
+	// The output can exist with no wlr_output if it's just been disconnected
+	// and the transaction to evacuate it has't completed yet.
+	if (output && output->wlr_output) {
+		wlr_output_damage_add_whole(output->damage);
+	}
 }
 
 static void damage_surface_iterator(struct sway_output *output,
@@ -446,14 +441,9 @@ void output_damage_surface(struct sway_output *output, double ox, double oy,
 
 static void output_damage_view(struct sway_output *output,
 		struct sway_view *view, bool whole) {
-	if (!sway_assert(view->swayc != NULL, "expected a view in the tree")) {
-		return;
-	}
-
 	if (!view_is_visible(view)) {
 		return;
 	}
-
 	output_view_for_each_surface(output, view, damage_surface_iterator, &whole);
 }
 
@@ -466,31 +456,29 @@ void output_damage_from_view(struct sway_output *output,
 void output_damage_box(struct sway_output *output, struct wlr_box *_box) {
 	struct wlr_box box;
 	memcpy(&box, _box, sizeof(struct wlr_box));
-	box.x -= output->swayc->current.swayc_x;
-	box.y -= output->swayc->current.swayc_y;
+	box.x -= output->wlr_output->lx;
+	box.y -= output->wlr_output->ly;
 	scale_box(&box, output->wlr_output->scale);
 	wlr_output_damage_add_box(output->damage, &box);
 }
 
 static void output_damage_whole_container_iterator(struct sway_container *con,
 		void *data) {
-	struct sway_output *output = data;
-
-	if (!sway_assert(con->type == C_VIEW, "expected a view")) {
+	if (!sway_assert(con->view, "expected a view")) {
 		return;
 	}
-
-	output_damage_view(output, con->sway_view, true);
+	struct sway_output *output = data;
+	output_damage_view(output, con->view, true);
 }
 
 void output_damage_whole_container(struct sway_output *output,
 		struct sway_container *con) {
 	// Pad the box by 1px, because the width is a double and might be a fraction
 	struct wlr_box box = {
-		.x = con->current.swayc_x - output->wlr_output->lx - 1,
-		.y = con->current.swayc_y - output->wlr_output->ly - 1,
-		.width = con->current.swayc_width + 2,
-		.height = con->current.swayc_height + 2,
+		.x = con->current.con_x - output->wlr_output->lx - 1,
+		.y = con->current.con_y - output->wlr_output->ly - 1,
+		.width = con->current.con_width + 2,
+		.height = con->current.con_height + 2,
 	};
 	scale_box(&box, output->wlr_output->scale);
 	wlr_output_damage_add_box(output->damage, &box);
@@ -499,44 +487,48 @@ void output_damage_whole_container(struct sway_output *output,
 static void damage_handle_destroy(struct wl_listener *listener, void *data) {
 	struct sway_output *output =
 		wl_container_of(listener, output, damage_destroy);
-	output_begin_destroy(output->swayc);
+	output_disable(output);
+	transaction_commit_dirty();
 }
 
 static void handle_destroy(struct wl_listener *listener, void *data) {
 	struct sway_output *output = wl_container_of(listener, output, destroy);
 	wl_signal_emit(&output->events.destroy, output);
 
-	if (output->swayc) {
-		output_begin_destroy(output->swayc);
+	if (output->enabled) {
+		output_disable(output);
 	}
+	output_begin_destroy(output);
 
-	wl_list_remove(&output->link);
-	wl_list_remove(&output->destroy.link);
-	output->wlr_output->data = NULL;
-	free(output);
-
-	arrange_windows(&root_container);
+	transaction_commit_dirty();
 }
 
 static void handle_mode(struct wl_listener *listener, void *data) {
 	struct sway_output *output = wl_container_of(listener, output, mode);
 	arrange_layers(output);
-	arrange_windows(output->swayc);
+	arrange_output(output);
 	transaction_commit_dirty();
 }
 
 static void handle_transform(struct wl_listener *listener, void *data) {
 	struct sway_output *output = wl_container_of(listener, output, transform);
 	arrange_layers(output);
-	arrange_windows(output->swayc);
+	arrange_output(output);
 	transaction_commit_dirty();
 }
 
+static void update_textures(struct sway_container *con, void *data) {
+	container_update_title_textures(con);
+	if (con->view) {
+		view_update_marks_textures(con->view);
+	}
+}
+
 static void handle_scale(struct wl_listener *listener, void *data) {
 	struct sway_output *output = wl_container_of(listener, output, scale);
 	arrange_layers(output);
-	container_update_textures_recursive(output->swayc);
-	arrange_windows(output->swayc);
+	output_for_each_container(output, update_textures, NULL);
+	arrange_output(output);
 	transaction_commit_dirty();
 }
 
@@ -545,57 +537,27 @@ void handle_new_output(struct wl_listener *listener, void *data) {
 	struct wlr_output *wlr_output = data;
 	wlr_log(WLR_DEBUG, "New output %p: %s", wlr_output, wlr_output->name);
 
-	struct sway_output *output = calloc(1, sizeof(struct sway_output));
+	struct sway_output *output = output_create(wlr_output);
 	if (!output) {
 		return;
 	}
-	output->wlr_output = wlr_output;
-	wlr_output->data = output;
 	output->server = server;
 	output->damage = wlr_output_damage_create(wlr_output);
-
-	wl_signal_add(&wlr_output->events.destroy, &output->destroy);
 	output->destroy.notify = handle_destroy;
 
-	wl_list_insert(&root_container.sway_root->all_outputs, &output->link);
+	struct output_config *oc = output_find_config(output);
 
-	output_enable(output);
-}
-
-void output_enable(struct sway_output *output) {
-	struct wlr_output *wlr_output = output->wlr_output;
-
-	if (!sway_assert(output->swayc == NULL, "output is already enabled")) {
-		return;
+	if (oc && oc->enabled) {
+		output_enable(output, oc);
 	}
 
-	output->swayc = output_create(output);
-	if (!output->swayc) {
-		// Output is disabled
-		return;
-	}
-
-	size_t len = sizeof(output->layers) / sizeof(output->layers[0]);
-	for (size_t i = 0; i < len; ++i) {
-		wl_list_init(&output->layers[i]);
-	}
-	wl_signal_init(&output->events.destroy);
-
-	input_manager_configure_xcursor(input_manager);
-
-	wl_signal_add(&wlr_output->events.mode, &output->mode);
-	output->mode.notify = handle_mode;
-	wl_signal_add(&wlr_output->events.transform, &output->transform);
-	output->transform.notify = handle_transform;
-	wl_signal_add(&wlr_output->events.scale, &output->scale);
-	output->scale.notify = handle_scale;
-
-	wl_signal_add(&output->damage->events.frame, &output->damage_frame);
-	output->damage_frame.notify = damage_handle_frame;
-	wl_signal_add(&output->damage->events.destroy, &output->damage_destroy);
-	output->damage_destroy.notify = damage_handle_destroy;
-
-	arrange_layers(output);
-	arrange_windows(&root_container);
 	transaction_commit_dirty();
 }
+
+void output_add_listeners(struct sway_output *output) {
+	output->mode.notify = handle_mode;
+	output->transform.notify = handle_transform;
+	output->scale.notify = handle_scale;
+	output->damage_frame.notify = damage_handle_frame;
+	output->damage_destroy.notify = damage_handle_destroy;
+}