return existing;
}
+
+int submodule_uses_worktrees(const char *path)
+{
+ char *submodule_gitdir;
+ struct strbuf sb = STRBUF_INIT;
+ DIR *dir;
+ struct dirent *d;
+ int ret = 0;
+ struct repository_format format;
+
+ submodule_gitdir = git_pathdup_submodule(path, "%s", "");
+ if (!submodule_gitdir)
+ return 0;
+
+ /* The env would be set for the superproject. */
+ get_common_dir_noenv(&sb, submodule_gitdir);
+
+ /*
+ * The check below is only known to be good for repository format
+ * version 0 at the time of writing this code.
+ */
+ strbuf_addstr(&sb, "/config");
+ read_repository_format(&format, sb.buf);
+ if (format.version != 0) {
+ strbuf_release(&sb);
+ return 1;
+ }
+
+ /* Replace config by worktrees. */
+ strbuf_setlen(&sb, sb.len - strlen("config"));
+ strbuf_addstr(&sb, "worktrees");
+
+ /* See if there is any file inside the worktrees directory. */
+ dir = opendir(sb.buf);
+ strbuf_release(&sb);
+ free(submodule_gitdir);
+
+ if (!dir)
+ return 0;
+
+ while ((d = readdir(dir)) != NULL) {
+ if (is_dot_or_dotdot(d->d_name))
+ continue;
+
+ ret = 1;
+ break;
+ }
+ closedir(dir);
+ return ret;
+}