Implement iterators per container type

This introduces the following `for_each` functions:

* root_for_each_workspace
* root_for_each_container
* output_for_each_workspace
* output_for_each_container
* workspace_for_each_container

And introduces the following `find` functions:

* root_find_output
* root_find_workspace
* root_find_container
* output_find_workspace
* output_find_container
* workspace_find_container
* container_find_child

And removes the following functions:

* container_descendants
* container_for_each_descendant
* container_find

This change is preparing the way for demoting sway_container. Eventually
these functions will accept and return sway_outputs, sway_workspaces and
sway_containers (meaning a C_CONTAINER or C_VIEW).

This change also makes it easy to handle abnormalities like the
workspace floating list, root's scratchpad list and (once implemented)
root's saved workspaces list for when there's no connected outputs.

1 files changed, 62 insertions, 9 deletions

diff --git a/sway/tree/workspace.c b/sway/tree/workspace.c
index 1c0e6515..b7090de6 100644
--- a/sway/tree/workspace.c
+++ b/sway/tree/workspace.c
@@ -244,8 +244,7 @@ struct sway_container *workspace_by_number(const char* name) {
         if (wbnd.len <= 0) {
                 return NULL;
         }
-        return container_find(&root_container,
-                        _workspace_by_number, (void *) &wbnd);
+        return root_find_workspace(_workspace_by_number, (void *) &wbnd);
 }
 
 static bool _workspace_by_name(struct sway_container *view, void *data) {
@@ -274,11 +273,11 @@ struct sway_container *workspace_by_name(const char *name) {
         } else if (strcmp(name, "current") == 0) {
                 return current_workspace;
         } else if (strcasecmp(name, "back_and_forth") == 0) {
-                return prev_workspace_name ? container_find(&root_container,
-                                _workspace_by_name, (void *)prev_workspace_name) : NULL;
+                return prev_workspace_name ?
+                        root_find_workspace(_workspace_by_name, (void*)prev_workspace_name)
+                        : NULL;
         } else {
-                return container_find(&root_container, _workspace_by_name,
-                                (void *)name);
+                return root_find_workspace(_workspace_by_name, (void*)name);
         }
 }
 
@@ -518,8 +517,7 @@ struct sway_container *workspace_output_get_highest_available(
                         continue;
                 }
 
-                struct sway_container *output = container_find(&root_container,
-                                _output_by_name, name);
+                struct sway_container *output = root_find_output(_output_by_name, name);
                 if (output) {
                         return output;
                 }
@@ -528,8 +526,13 @@ struct sway_container *workspace_output_get_highest_available(
         return NULL;
 }
 
+static bool find_urgent_iterator(struct sway_container *con, void *data) {
+        return con->type == C_VIEW && view_is_urgent(con->sway_view);
+}
+
 void workspace_detect_urgent(struct sway_container *workspace) {
-        bool new_urgent = container_has_urgent_child(workspace);
+        bool new_urgent = (bool)workspace_find_container(workspace,
+                        find_urgent_iterator, NULL);
 
         if (workspace->sway_workspace->urgent != new_urgent) {
                 workspace->sway_workspace->urgent = new_urgent;
@@ -538,6 +541,56 @@ void workspace_detect_urgent(struct sway_container *workspace) {
         }
 }
 
+void workspace_for_each_container(struct sway_container *ws,
+                void (*f)(struct sway_container *con, void *data), void *data) {
+        if (!sway_assert(ws->type == C_WORKSPACE, "Expected a workspace")) {
+                return;
+        }
+        // Tiling
+        for (int i = 0; i < ws->children->length; ++i) {
+                struct sway_container *container = ws->children->items[i];
+                f(container, data);
+                container_for_each_child(container, f, data);
+        }
+        // Floating
+        for (int i = 0; i < ws->sway_workspace->floating->children->length; ++i) {
+                struct sway_container *container =
+                        ws->sway_workspace->floating->children->items[i];
+                f(container, data);
+                container_for_each_child(container, f, data);
+        }
+}
+
+struct sway_container *workspace_find_container(struct sway_container *ws,
+                bool (*test)(struct sway_container *con, void *data), void *data) {
+        if (!sway_assert(ws->type == C_WORKSPACE, "Expected a workspace")) {
+                return NULL;
+        }
+        struct sway_container *result = NULL;
+        // Tiling
+        for (int i = 0; i < ws->children->length; ++i) {
+                struct sway_container *child = ws->children->items[i];
+                if (test(child, data)) {
+                        return child;
+                }
+                if ((result = container_find_child(child, test, data))) {
+                        return result;
+                }
+        }
+        // Floating
+        for (int i = 0; i < ws->sway_workspace->floating->children->length; ++i) {
+                struct sway_container *child =
+                        ws->sway_workspace->floating->children->items[i];
+                if (test(child, data)) {
+                        return child;
+                }
+                if ((result = container_find_child(child, test, data))) {
+                        return result;
+                }
+        }
+        return NULL;
+}
+
 struct sway_container *workspace_wrap_children(struct sway_container *ws) {
         struct sway_container *middle = container_create(C_CONTAINER);
         middle->layout = ws->layout;