Re: [PATCH v2 3/4] parse_commit(): handle broken whitespace-only timestamp

[Andreas Schwab <schwab@linux-m68k.org>]

On Apr 26 2023, Phillip Wood wrote:

> On 25/04/2023 17:06, Junio C Hamano wrote:
>> Phillip Wood <phillip.wood123@gmail.com> writes:
>> 
>>> This probably doesn't matter in practice but we define our own
>>> isspace() that does not treat '\v' and '\f' as whitespace. However
>>> parse_timestamp() (which is just strtoumax()) uses the standard
>>> library's isspace() which does treat those characters as whitespace
>>> and is locale dependent. This means we can potentially stop at a
>>> character that parse_timestamp() treats as whitespace and if there are
>>> no digits after it we'll still walk past the end of the line. Using
>>> Rene's suggestion of testing the character with isdigit() would fix
>>> that. It would also avoid parsing negative timestamps as positive
>>> numbers 
>
>>> and reject any timestamps that begin with a locale dependent
>>> digit.
>
> Sorry, that bit is not correct, I've since checked the C standard and I
> think strtoul() and friends expect ascii digits (isdigit() and isxdigit()
> are also locale independent unlike isspace(), isalpha() etc.)

The standard says:

    In other than the "C" locale, additional locale-specific subject
    sequence forms may be accepted.

-- 
Andreas Schwab, schwab@linux-m68k.org
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