extern int ws_blank_line(const char *line, int len, unsigned ws_rule);
/* ls-files */
-int pathspec_match(const char **spec, char *matched, const char *filename, int skiplen);
int report_path_error(const char *ps_matched, const char **pathspec, int prefix_offset);
void overlay_tree_on_cache(const char *tree_name, const char *prefix);