Re: [PATCH v2 1/4] revision: improve commit_rewrite_person()

[Christian Couder <christian.couder@gmail.com>]

On Sat, Jul 9, 2022 at 3:02 AM Đoàn Trần Công Danh <congdanhqx@gmail.com> wrote:
>
> Add list back to cc

Sorry for not keeping the list in Cc by mistake.

> On 2022-07-08 23:23:07+0200, Christian Couder <christian.couder@gmail.com> wrote:
> > On Fri, Jul 8, 2022 at 4:50 PM Đoàn Trần Công Danh <congdanhqx@gmail.com> wrote:
> > >
> > > On 2022-07-07 21:45:51+0530, Siddharth Asthana <siddharthasthana31@gmail.com> wrote:
> >
> > > > By simplyfying the interface of the commit_rewrite_person(), we also
> > >
> > > s/simplyfying/simplifying/
> >
> > Thanks for noticing the typos!
> >
> > > > +static void commit_rewrite_person(struct strbuf *buf, const char **headers, struct string_list *mailmap)
> > > > +{
> > > > +     size_t buf_offset = 0;
> > > > +
> > > > +     if (!mailmap)
> > > > +             return;
> > > > +
> > > > +     for (;;) {
> > > > +             const char *person, *line = buf->buf + buf_offset;
> > > > +             int i, linelen = strchrnul(line, '\n') - line + 1;
> > >
> > > Would you mind to change those lines to avoid mixed of declaration and
> > > expression.
> >
> > I am not sure we have some clear guidelines on this.
>
> Yes, we don't have a clear guidelines on this, but this would sure
> matches into mixed declaration and expression. And some variables are
> initialized and some aren't in the same line. I was confused in my
> first glance.

Yeah, it might be clearer to avoid having some variables both declared
and initialized while others are only declared on the same line.

> > > Also, I think i and linelen should be ssize_t instead.
> >
> > Could you explain why?
> >
> > I think 'i' is changed only in:
> >
> > for (i = 0; headers[i]; i++)
> >
> > and therefore cannot be négative.
> >
> > While linelen is set only in:
> >
> > linelen = strchrnul(line, '\n') - line + 1;
> >
> > and therefore cannot be négative either.
>
> Yes, both of them can't be negative. As I explained in the part you
> removed.  However, I choose ssize_t in my reply because it's
> a ptrdiff_t.
>
> So, size_t is an obviously a better choice.
> Either size_t and ssize_t could be used in this case, but not int.

I am Ok with size_t. Thanks for the explanations!

> >>> +
> >>> +             if (!linelen || linelen == 1)
> >>> +                     /* End of header */
> >>> +                     return;
> >>
> >>And I think linelen will never be 0 or negative,
> >>even if linelen could be 0, I think we want "linelen != 0"
> >>for integer comparision.

maybe `if (linelen <=1)` is just a simpler check.