(AUTHORS): Add self.
Change "path" to "file name" whenever possible.
Remove usage comment, as it was a duplication of the code or doc.
Include <wchar.h> if available.
(mbrlen, mbstate_t) [! (HAVE_MBRLEN && HAVE_MBSTATE_T)]: Define.
(NEED_PATHCONF_WRAPPER, PATH_MAX, PATH_MAX_FOR, NAME_MAX,
pathconf_wrapper, portable_chars, dir_ok): Remove.
(NAME_MAX_MINIMUM, PATH_MAX_MINIMUM): New macros.
(pathconf, _PC_NAME_MAX, _PC_PATH_MAX): Define if nonexistent.
(portable_chars_only): New arg FILELEN.
Don't assume ASCII; we might be on an EBCDIC host.
Don't assume unibyte locale in diagnostic.
(component_start, component_len): New functions.
(validate_file_name): Renamed from validate_path. All uses changed.
Pretty much a complete rewrite.
Don't make copy of file arg. Always append trailing slash to
pathconf arg, just in case it's a symlink (this is pure paranoia;
we don't know of any hosts where the trailing slash is required).
Use size_t instead of long int when possible.
Avoid need to call pathconf in most practical cases.
Don't use euidaccess several times to test searchability;
just use lstat once. Reword diagnostic to put the (often very long)
file names last.