7 files changed, 79 insertions, 83 deletions

diff --git a/common/stringop.c b/common/stringop.c
index 4a37543d..d9ae9925 100644
--- a/common/stringop.c
+++ b/common/stringop.c
@@ -55,6 +55,20 @@ void strip_quotes(char *str) {
         *end = '\0';
 }
 
+char *lenient_strcat(char *dest, const char *src) {
+        if (dest && src) {
+                return strcat(dest, src);
+        }
+        return dest;
+}
+
+char *lenient_strncat(char *dest, const char *src, size_t len) {
+        if (dest && src) {
+                return strncat(dest, src, len);
+        }
+        return dest;
+}
+
 // strcmp that also handles null pointers.
 int lenient_strcmp(char *a, char *b) {
         if (a == b) {
diff --git a/include/stringop.h b/include/stringop.h
index 7c29a745..e7f58011 100644
--- a/include/stringop.h
+++ b/include/stringop.h
@@ -1,5 +1,6 @@
 #ifndef _SWAY_STRINGOP_H
 #define _SWAY_STRINGOP_H
+#include <stdlib.h>
 #include "list.h"
 
 #if !HAVE_DECL_SETENV
@@ -14,6 +15,10 @@ char *strip_whitespace(char *str);
 char *strip_comments(char *str);
 void strip_quotes(char *str);
 
+// strcat that does nothing if dest or src is NULL
+char *lenient_strcat(char *dest, const char *src);
+char *lenient_strncat(char *dest, const char *src, size_t len);
+
 // strcmp that also handles null pointers.
 int lenient_strcmp(char *a, char *b);
 
diff --git a/include/sway/tree/container.h b/include/sway/tree/container.h
index 493c70e2..a5f591ce 100644
--- a/include/sway/tree/container.h
+++ b/include/sway/tree/container.h
@@ -216,7 +216,11 @@ void container_update_title_textures(struct sway_container *container);
  */
 void container_calculate_title_height(struct sway_container *container);
 
-void container_notify_child_title_changed(struct sway_container *container);
+/**
+ * Notify a container that a tree modification has changed in its children,
+ * so the container can update its tree representation.
+ */
+void container_notify_subtree_changed(struct sway_container *container);
 
 /**
  * Return the height of a regular title bar.
diff --git a/sway/commands/layout.c b/sway/commands/layout.c
index 58728f16..6b44b001 100644
--- a/sway/commands/layout.c
+++ b/sway/commands/layout.c
@@ -52,6 +52,7 @@ struct cmd_results *cmd_layout(int argc, char **argv) {
                 }
         }
 
+        container_notify_subtree_changed(parent);
         arrange_children_of(parent);
 
         return cmd_results_new(CMD_SUCCESS, NULL, NULL);
diff --git a/sway/tree/container.c b/sway/tree/container.c
index 9cf18f61..f29a9adc 100644
--- a/sway/tree/container.c
+++ b/sway/tree/container.c
@@ -21,6 +21,7 @@
 #include "sway/tree/view.h"
 #include "sway/tree/workspace.h"
 #include "log.h"
+#include "stringop.h"
 
 static list_t *bfs_queue;
 
@@ -774,42 +775,36 @@ void container_calculate_title_height(struct sway_container *container) {
 }
 
 /**
- * Calculate and return the length of the concatenated child titles.
- * An example concatenated title is: V[Terminal, Firefox]
- * If buffer is not NULL, also populate the buffer with the concatenated title.
+ * Calculate and return the length of the tree representation.
+ * An example tree representation is: V[Terminal, Firefox]
+ * If buffer is not NULL, also populate the buffer with the representation.
  */
-static size_t concatenate_child_titles(struct sway_container *parent,
-                char *buffer) {
-        size_t len = 2; // V[
-        if (buffer) {
-                switch (parent->layout) {
-                case L_VERT:
-                        strcpy(buffer, "V[");
-                        break;
-                case L_HORIZ:
-                        strcpy(buffer, "H[");
-                        break;
-                case L_TABBED:
-                        strcpy(buffer, "T[");
-                        break;
-                case L_STACKED:
-                        strcpy(buffer, "S[");
-                        break;
-                case L_FLOATING:
-                        strcpy(buffer, "F[");
-                        break;
-                case L_NONE:
-                        strcpy(buffer, "D[");
-                        break;
-                }
+static size_t get_tree_representation(struct sway_container *parent, char *buffer) {
+        size_t len = 2;
+        switch (parent->layout) {
+        case L_VERT:
+                lenient_strcat(buffer, "V[");
+                break;
+        case L_HORIZ:
+                lenient_strcat(buffer, "H[");
+                break;
+        case L_TABBED:
+                lenient_strcat(buffer, "T[");
+                break;
+        case L_STACKED:
+                lenient_strcat(buffer, "S[");
+                break;
+        case L_FLOATING:
+                lenient_strcat(buffer, "F[");
+                break;
+        case L_NONE:
+                lenient_strcat(buffer, "D[");
+                break;
         }
-
         for (int i = 0; i < parent->children->length; ++i) {
                 if (i != 0) {
-                        len += 1;
-                        if (buffer) {
-                                strcat(buffer, " ");
-                        }
+                        ++len;
+                        lenient_strcat(buffer, " ");
                 }
                 struct sway_container *child = parent->children->items[i];
                 const char *identifier = NULL;
@@ -819,48 +814,39 @@ static size_t concatenate_child_titles(struct sway_container *parent,
                                 identifier = view_get_app_id(child->sway_view);
                         }
                 } else {
-                        identifier = child->name;
+                        identifier = child->formatted_title;
                 }
                 if (identifier) {
                         len += strlen(identifier);
-                        if (buffer) {
-                                strcat(buffer, identifier);
-                        }
+                        lenient_strcat(buffer, identifier);
                 } else {
                         len += 6;
-                        if (buffer) {
-                                strcat(buffer, "(null)");
-                        }
+                        lenient_strcat(buffer, "(null)");
                 }
         }
-
-        len += 1;
-        if (buffer) {
-                strcat(buffer, "]");
-        }
+        ++len;
+        lenient_strcat(buffer, "]");
         return len;
 }
 
-void container_notify_child_title_changed(struct sway_container *container) {
+void container_notify_subtree_changed(struct sway_container *container) {
         if (!container || container->type != C_CONTAINER) {
                 return;
         }
-        if (container->formatted_title) {
-                free(container->formatted_title);
-        }
+        free(container->formatted_title);
+        container->formatted_title = NULL;
 
-        size_t len = concatenate_child_titles(container, NULL);
+        size_t len = get_tree_representation(container, NULL);
         char *buffer = calloc(len + 1, sizeof(char));
         if (!sway_assert(buffer, "Unable to allocate title string")) {
                 return;
         }
-        concatenate_child_titles(container, buffer);
+        get_tree_representation(container, buffer);
 
-        container->name = buffer;
         container->formatted_title = buffer;
         container_calculate_title_height(container);
         container_update_title_textures(container);
-        container_notify_child_title_changed(container->parent);
+        container_notify_subtree_changed(container->parent);
 }
 
 size_t container_titlebar_height() {
diff --git a/sway/tree/layout.c b/sway/tree/layout.c
index 91759f7b..edc24deb 100644
--- a/sway/tree/layout.c
+++ b/sway/tree/layout.c
@@ -149,7 +149,7 @@ struct sway_container *container_remove_child(struct sway_container *child) {
                 }
         }
         child->parent = NULL;
-        container_notify_child_title_changed(parent);
+        container_notify_subtree_changed(parent);
 
         return parent;
 }
@@ -184,8 +184,8 @@ void container_move_to(struct sway_container *container,
                 container_sort_workspaces(new_parent);
                 seat_set_focus(seat, new_parent);
         }
-        container_notify_child_title_changed(old_parent);
-        container_notify_child_title_changed(new_parent);
+        container_notify_subtree_changed(old_parent);
+        container_notify_subtree_changed(new_parent);
         if (old_parent) {
                 if (old_parent->type == C_OUTPUT) {
                         arrange_output(old_parent);
@@ -497,8 +497,8 @@ void container_move(struct sway_container *container,
                 }
         }
 
-        container_notify_child_title_changed(old_parent);
-        container_notify_child_title_changed(container->parent);
+        container_notify_subtree_changed(old_parent);
+        container_notify_subtree_changed(container->parent);
 
         if (old_parent) {
                 seat_set_focus(config->handler_context.seat, old_parent);
@@ -847,7 +847,7 @@ struct sway_container *container_split(struct sway_container *child,
                 container_add_child(cont, child);
         }
 
-        container_notify_child_title_changed(cont);
+        container_notify_subtree_changed(cont);
 
         return cont;
 }
diff --git a/sway/tree/view.c b/sway/tree/view.c
index 07157818..2f718a73 100644
--- a/sway/tree/view.c
+++ b/sway/tree/view.c
@@ -17,6 +17,7 @@
 #include "sway/tree/workspace.h"
 #include "sway/config.h"
 #include "pango.h"
+#include "stringop.h"
 
 void view_init(struct sway_view *view, enum sway_view_type type,
                 const struct sway_view_impl *impl) {
@@ -470,7 +471,7 @@ void view_map(struct sway_view *view, struct wlr_surface *wlr_surface) {
         input_manager_set_focus(input_manager, cont);
 
         view_update_title(view, false);
-        container_notify_child_title_changed(view->swayc->parent);
+        container_notify_subtree_changed(view->swayc->parent);
         view_execute_criteria(view);
 
         container_damage_whole(cont);
@@ -661,49 +662,35 @@ static size_t parse_title_format(struct sway_view *view, char *buffer) {
         char *format = view->title_format;
         char *next = strchr(format, '%');
         while (next) {
-                if (buffer) {
-                        // Copy everything up to the %
-                        strncat(buffer, format, next - format);
-                }
+                // Copy everything up to the %
+                lenient_strncat(buffer, format, next - format);
                 len += next - format;
                 format = next;
 
                 if (strncmp(next, "%title", 6) == 0) {
-                        if (buffer && title) {
-                                strcat(buffer, title);
-                        }
+                        lenient_strcat(buffer, title);
                         len += title_len;
                         format += 6;
                 } else if (strncmp(next, "%class", 6) == 0) {
-                        if (buffer && class) {
-                                strcat(buffer, class);
-                        }
+                        lenient_strcat(buffer, class);
                         len += class_len;
                         format += 6;
                 } else if (strncmp(next, "%instance", 9) == 0) {
-                        if (buffer && instance) {
-                                strcat(buffer, instance);
-                        }
+                        lenient_strcat(buffer, instance);
                         len += instance_len;
                         format += 9;
                 } else if (strncmp(next, "%shell", 6) == 0) {
-                        if (buffer) {
-                                strcat(buffer, shell);
-                        }
+                        lenient_strcat(buffer, shell);
                         len += shell_len;
                         format += 6;
                 } else {
-                        if (buffer) {
-                                strcat(buffer, "%");
-                        }
+                        lenient_strcat(buffer, "%");
                         ++format;
                         ++len;
                 }
                 next = strchr(format, '%');
         }
-        if (buffer) {
-                strcat(buffer, format);
-        }
+        lenient_strcat(buffer, format);
         len += strlen(format);
 
         return len;
@@ -759,7 +746,6 @@ void view_update_title(struct sway_view *view, bool force) {
         }
         container_calculate_title_height(view->swayc);
         container_update_title_textures(view->swayc);
-        container_notify_child_title_changed(view->swayc->parent);
         config_update_font_height(false);
 }