Implement atomic layout updates for tree operations

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

1 files changed, 93 insertions, 91 deletions

diff --git a/sway/tree/container.c b/sway/tree/container.c
index b071f394..484d26a5 100644
--- a/sway/tree/container.c
+++ b/sway/tree/container.c
@@ -16,7 +16,6 @@
 #include "sway/ipc-server.h"
 #include "sway/output.h"
 #include "sway/server.h"
-#include "sway/tree/arrange.h"
 #include "sway/tree/layout.h"
 #include "sway/tree/view.h"
 #include "sway/tree/workspace.h"
@@ -113,10 +112,11 @@ struct sway_container *container_create(enum sway_container_type type) {
         c->layout = L_NONE;
         c->type = type;
         c->alpha = 1.0f;
+        c->instructions = create_list();
 
         if (type != C_VIEW) {
                 c->children = create_list();
-                //c->pending.children = create_list();
+                c->current.children = create_list();
         }
 
         wl_signal_init(&c->events.destroy);
@@ -133,43 +133,68 @@ struct sway_container *container_create(enum sway_container_type type) {
         return c;
 }
 
-static void _container_destroy(struct sway_container *cont) {
-        if (cont == NULL) {
-                return;
-        }
-
-        wl_signal_emit(&cont->events.destroy, cont);
+static void container_workspace_free(struct sway_workspace *ws) {
+        list_foreach(ws->output_priority, free);
+        list_free(ws->output_priority);
+        ws->floating->destroying = true;
+        container_free(ws->floating);
+        free(ws);
+}
 
-        struct sway_container *parent = cont->parent;
-        if (cont->children != NULL && cont->children->length) {
-                // remove children until there are no more, container_destroy calls
-                // container_remove_child, which removes child from this container
-                while (cont->children != NULL && cont->children->length > 0) {
-                        struct sway_container *child = cont->children->items[0];
-                        ipc_event_window(child, "close");
-                        container_remove_child(child);
-                        _container_destroy(child);
-                }
-        }
-        if (cont->marks) {
-                list_foreach(cont->marks, free);
-                list_free(cont->marks);
-        }
-        if (parent) {
-                parent = container_remove_child(cont);
+void container_free(struct sway_container *cont) {
+        if (!sway_assert(cont->destroying,
+                                "Tried to free container which wasn't marked as destroying")) {
+                return;
         }
-        if (cont->name) {
-                free(cont->name);
+        if (!sway_assert(cont->instructions->length == 0,
+                                "Tried to free container with pending instructions")) {
+                return;
         }
-
+        free(cont->name);
         wlr_texture_destroy(cont->title_focused);
         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->pending.children);
-        cont->children = NULL;
+        list_free(cont->current.children);
+
+        switch (cont->type) {
+        case C_ROOT:
+                break;
+        case C_OUTPUT:
+                cont->sway_output->swayc = NULL;
+                break;
+        case C_WORKSPACE:
+                container_workspace_free(cont->sway_workspace);
+                break;
+        case C_CONTAINER:
+                break;
+        case C_VIEW:
+                {
+                        struct sway_view *view = cont->sway_view;
+                        view->swayc = NULL;
+                        free(view->title_format);
+                        view->title_format = NULL;
+
+                        if (view->destroying) {
+                                view_free(view);
+                        }
+                }
+                break;
+        case C_TYPES:
+                sway_assert(false, "Didn't expect to see C_TYPES here");
+                break;
+        }
+
         free(cont);
 }
 
@@ -186,7 +211,6 @@ static struct sway_container *container_workspace_destroy(
         }
 
         wlr_log(L_DEBUG, "destroying workspace '%s'", workspace->name);
-        ipc_event_window(workspace, "close");
 
         struct sway_container *parent = workspace->parent;
         if (!workspace_is_empty(workspace) && output) {
@@ -209,25 +233,6 @@ static struct sway_container *container_workspace_destroy(
                         container_move_to(floating->children->items[i],
                                         new_workspace->sway_workspace->floating);
                 }
-                arrange_and_commit(new_workspace);
-        }
-
-        struct sway_workspace *sway_workspace = workspace->sway_workspace;
-
-        // This emits the destroy event and also destroys the swayc.
-        _container_destroy(workspace);
-
-        // Clean up the floating container
-        sway_workspace->floating->parent = NULL;
-        _container_destroy(sway_workspace->floating);
-
-        list_foreach(sway_workspace->output_priority, free);
-        list_free(sway_workspace->output_priority);
-
-        free(sway_workspace);
-
-        if (output) {
-                output_damage_whole(output->sway_output);
         }
 
         return parent;
@@ -266,14 +271,13 @@ static struct sway_container *container_output_destroy(
                                         container_add_child(new_output, workspace);
                                         ipc_event_workspace(workspace, NULL, "move");
                                 } else {
-                                        container_workspace_destroy(workspace);
+                                        container_destroy(workspace);
                                 }
 
                                 container_sort_workspaces(new_output);
                         }
                 }
         }
-        arrange_and_commit(&root_container);
 
         wl_list_remove(&output->sway_output->mode.link);
         wl_list_remove(&output->sway_output->transform.link);
@@ -285,12 +289,8 @@ static struct sway_container *container_output_destroy(
         output->sway_output->swayc = NULL;
 
         wlr_log(L_DEBUG, "OUTPUT: Destroying output '%s'", output->name);
-        _container_destroy(output);
-        return &root_container;
-}
 
-static void container_root_finish(struct sway_container *con) {
-        wlr_log(L_ERROR, "TODO: destroy the root container");
+        return &root_container;
 }
 
 bool container_reap_empty(struct sway_container *con) {
@@ -306,13 +306,13 @@ bool container_reap_empty(struct sway_container *con) {
         case C_WORKSPACE:
                 if (!workspace_is_visible(con) && workspace_is_empty(con)) {
                         wlr_log(L_DEBUG, "Destroying workspace via reaper");
-                        container_workspace_destroy(con);
+                        container_destroy(con);
                         return true;
                 }
                 break;
         case C_CONTAINER:
                 if (con->children->length == 0) {
-                        _container_destroy(con);
+                        container_destroy(con);
                         return true;
                 }
         case C_VIEW:
@@ -349,46 +349,48 @@ struct sway_container *container_flatten(struct sway_container *container) {
         return container;
 }
 
+/**
+ * container_destroy() is the first step in destroying a container. We'll emit
+ * events, detach it from the tree and mark it as destroying. The container will
+ * remain in memory until it's no longer used by a transaction, then it will be
+ * freed via container_free().
+ */
 struct sway_container *container_destroy(struct sway_container *con) {
         if (con == NULL) {
                 return NULL;
         }
+        if (con->destroying) {
+                return NULL;
+        }
 
-        struct sway_container *parent = con->parent;
+        // The below functions move their children to somewhere else.
+        if (con->type == C_OUTPUT) {
+                container_output_destroy(con);
+        } else if (con->type == C_WORKSPACE) {
+                // Workspaces will refuse to be destroyed if they're the last workspace
+                // on their output.
+                if (!container_workspace_destroy(con)) {
+                        return NULL;
+                }
+        }
 
-        switch (con->type) {
-                case C_ROOT:
-                        container_root_finish(con);
-                        break;
-                case C_OUTPUT:
-                        // dont try to reap the root after this
-                        container_output_destroy(con);
-                        break;
-                case C_WORKSPACE:
-                        // dont try to reap the output after this
-                        container_workspace_destroy(con);
-                        break;
-                case C_CONTAINER:
-                        if (con->children->length) {
-                                for (int i = 0; i < con->children->length; ++i) {
-                                        struct sway_container *child = con->children->items[0];
-                                        ipc_event_window(child, "close");
-                                        container_remove_child(child);
-                                        container_add_child(parent, child);
-                                }
-                        }
-                        ipc_event_window(con, "close");
-                        _container_destroy(con);
-                        break;
-                case C_VIEW:
-                        _container_destroy(con);
-                        break;
-                case C_TYPES:
-                        wlr_log(L_ERROR, "container_destroy called on an invalid "
-                                "container");
-                        break;
+        // At this point the container being destroyed shouldn't have any children
+        // unless sway is terminating.
+        if (!server.terminating) {
+                if (!sway_assert(!con->children || con->children->length == 0,
+                                        "Didn't expect to see children here")) {
+                        return NULL;
+                }
         }
 
+        wl_signal_emit(&con->events.destroy, con);
+        ipc_event_window(con, "close");
+
+        struct sway_container *parent = container_remove_child(con);
+
+        con->destroying = true;
+        list_add(server.destroying_containers, con);
+
         return container_reap_empty_recursive(parent);
 }