On 2020-04-23 13:18:25-0700, Junio C Hamano <gitster@xxxxxxxxx> wrote:
> Đoàn Trần Công Danh <congdanhqx@xxxxxxxxx> writes:
>
> > In a later patch, we will reuse this logic, move it to a helper, now.
> >
> > While we're at it, explicit states that we intentionally ignore
>
> "explicitly state", perhaps.
>
> > old-and-defective 2nd leap second.
> >
> > Signed-off-by: Đoàn Trần Công Danh <congdanhqx@xxxxxxxxx>
> > ---
> > date.c | 22 +++++++++++++++++-----
> > 1 file changed, 17 insertions(+), 5 deletions(-)
> >
> > diff --git a/date.c b/date.c
> > index b67c5abe24..f5d5a91208 100644
> > --- a/date.c
> > +++ b/date.c
> > @@ -539,6 +539,22 @@ static int set_date(int year, int month, int day, struct tm *now_tm, time_t now,
> > return -1;
> > }
> >
> > +static int set_time(long hour, long minute, long second, struct tm *tm)
> > +{
> > + /* C90 and old POSIX accepts 2 leap seconds, it's a defect,
> > + * ignore second number 61
> > + */
>
> /*
> * Style: our multi-line comments ought to be
> * formatted like this. Slash-asterisk that opens,
> * and asterisk-slash that closes, are both on their
> * own lines.
> */
>
> But I am not sure we want to even have a new comment here. After
> all we are extracting/reinventing exactly the same logic as the
> original. Why we allow "60" might be worth commenting, but if a
> minute that has 62 seconds is a mere historical curiosity, then is
> it worth explaining why "61", which we never even wrote in the code,
> is missing from here?
I think single line like:
/* We accept 61st second for the single? leap second */
Or something along the time, is good enough. Not sure if we want the
word "single" there, though.
I think majority of people don't even know about leap second.
Probability that know about 62nd second is rarer, I think.
> > + if (0 <= hour && hour <= 24 &&
> > + 0 <= minute && minute < 60 &&
> > + 0 <= second && second <= 60) {
> > + tm->tm_hour = hour;
> > + tm->tm_min = minute;
> > + tm->tm_sec = second;
> > + return 0;
> > + }
> > + return -1;
> > +}
>
> I am a bit surprised to see that you chose to unify with the "check
> and set" interface of is_date (now set_date). I was expecting to
> see that we'd have "check-only" helper functions.
>
> This is not a complaint, at least not yet until we see the result of
> using it in new code; it may very well be possible that the "check
> and set" interface would make the new caller(s) clearer.
>
> > static int match_multi_number(timestamp_t num, char c, const char *date,
> > char *end, struct tm *tm, time_t now)
> > {
> > @@ -556,12 +572,8 @@ static int match_multi_number(timestamp_t num, char c, const char *date,
> > case ':':
> > if (num3 < 0)
> > num3 = 0;
> > - if (num < 25 && num2 >= 0 && num2 < 60 && num3 >= 0 && num3 <= 60) {
> > - tm->tm_hour = num;
> > - tm->tm_min = num2;
> > - tm->tm_sec = num3;
> > + if (set_time(num, num2, num3, tm) == 0)
> > break;
> > - }
> > return 0;
>
> This caller does become easier to follow, I would say. Nicely done.
Yes, when I looked around date.c
I saw that the only usecase for validate time is for setting it.
And the incoming patch also has that usage.
I chose to unify those code path to not buy me too much trouble.
I'll take that "Nicely done" means this unification is OK for this
series.
--
Danh
