Ranier Vilela <ranier...@gmail.com> writes:
> Em seg., 14 de set. de 2020 às 10:53, Daniel Gustafsson <dan...@yesql.se>
> escreveu:
>> If the objection is that an unsigned var is tested with <= 0, then
>> changing the
>> semantics of the function seems a rather drastic solution:
> But if wchar2char must be follow wcstombs_l API.
> wchar2char all calls must be:
> result = wchar2char();
> if (result == 0 || result == (size_t)-1) {
> See at lowerstr_with_len (src/backend/tsearch/ts_locale.c):
Actually, lowerstr_with_len is perfectly fine. It's coercing the
size_t result to int, so (size_t) -1 becomes integer -1 and its
error check for wlen < 0 is correct. It might have a problem if
the coercion to int could overflow, but that cannot happen because
of our restrictions on the size of a palloc'd chunk.
There are some other call sites that are failing to check at all,
which is not so good. But changing the function's API to be both
nonstandard and ambiguous (because a zero result is a perfectly valid
case) doesn't help fix that.
I concur with Daniel that none of the changes shown here are
worthwhile improvements. It's not illegal to test an unsigned
variable for "x <= 0".
regards, tom lane
