This block of code deals with the "basename" part only, which has the
length of "pathlen - (basename - pathname)". Stricten the length check
and remove "pathname" from the main expression to avoid confusion.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>