Sort(1)'s radixsort implementation was broken for multibyte LC_CTYPEs in at
least two ways:
* In actual radix sort, it would only bucket the least significant
byte from each wchar, ignoring the 24 most-significant bits of each
unicode character.
* In degenerate cases / "fast paths," it would fall back to another
sorting algorithm (default: mergesort) with a bogus comparator
offset. The string comparison functions in sort(1) take an offset
in units of the operating character size. However, radixsort was
passing an offset in units of bytes. The byte offset must be
divided by sizeof(wchar_t).
This revision addresses both discovered issues.
Some example testcases:
$ (echo 耳 ; echo 脳 ; echo 耳) | \
LC_CTYPE=ja_JP.UTF-8 LC_COLLATE=C LANG=C sort --radixsort --debug
$ (echo 耳 ; echo 脳 ; echo 耳) | \
LC_CTYPE=C LC_COLLATE=C LANG=C sort --radixsort --debug
$ (for i in $(jot 34); do echo 耳耳耳耳耳; echo 耳耳耳耳脳; echo 耳耳耳耳脴; done) | \
LC_CTYPE=ja_JP.UTF-8 LC_COLLATE=C LANG=C sort --radixsort --debug
PR: 247494
Reported by: knu
MFC after: I do not intend to, but parties interested in stable might want to