+static struct untracked_cache_dir *validate_untracked_cache(struct dir_struct *dir,
+ int base_len,
+ const struct pathspec *pathspec)
+{
+ struct untracked_cache_dir *root;
+
+ if (!dir->untracked)
+ return NULL;
+
+ /*
+ * We only support $GIT_DIR/info/exclude and core.excludesfile
+ * as the global ignore rule files. Any other additions
+ * (e.g. from command line) invalidate the cache. This
+ * condition also catches running setup_standard_excludes()
+ * before setting dir->untracked!
+ */
+ if (dir->unmanaged_exclude_files)
+ return NULL;
+
+ /*
+ * Optimize for the main use case only: whole-tree git
+ * status. More work involved in treat_leading_path() if we
+ * use cache on just a subset of the worktree. pathspec
+ * support could make the matter even worse.
+ */
+ if (base_len || (pathspec && pathspec->nr))
+ return NULL;
+
+ /* Different set of flags may produce different results */
+ if (dir->flags != dir->untracked->dir_flags ||
+ /*
+ * See treat_directory(), case index_nonexistent. Without
+ * this flag, we may need to also cache .git file content
+ * for the resolve_gitlink_ref() call, which we don't.
+ */
+ !(dir->flags & DIR_SHOW_OTHER_DIRECTORIES) ||
+ /* We don't support collecting ignore files */
+ (dir->flags & (DIR_SHOW_IGNORED | DIR_SHOW_IGNORED_TOO |
+ DIR_COLLECT_IGNORED)))
+ return NULL;
+
+ /*
+ * If we use .gitignore in the cache and now you change it to
+ * .gitexclude, everything will go wrong.
+ */
+ if (dir->exclude_per_dir != dir->untracked->exclude_per_dir &&
+ strcmp(dir->exclude_per_dir, dir->untracked->exclude_per_dir))
+ return NULL;
+
+ /*
+ * EXC_CMDL is not considered in the cache. If people set it,
+ * skip the cache.
+ */
+ if (dir->exclude_list_group[EXC_CMDL].nr)
+ return NULL;
+
+ if (!dir->untracked->root) {
+ const int len = sizeof(*dir->untracked->root);
+ dir->untracked->root = xmalloc(len);
+ memset(dir->untracked->root, 0, len);
+ }
+
+ /* Validate $GIT_DIR/info/exclude and core.excludesfile */
+ root = dir->untracked->root;
+ if (hashcmp(dir->ss_info_exclude.sha1,
+ dir->untracked->ss_info_exclude.sha1)) {
+ invalidate_gitignore(dir->untracked, root);
+ dir->untracked->ss_info_exclude = dir->ss_info_exclude;
+ }
+ if (hashcmp(dir->ss_excludes_file.sha1,
+ dir->untracked->ss_excludes_file.sha1)) {
+ invalidate_gitignore(dir->untracked, root);
+ dir->untracked->ss_excludes_file = dir->ss_excludes_file;
+ }
+ return root;
+}
+