Re: [PATCH v2] correct verify_path for Windows
- From
Alex Riesen <raa.lkml@gmail.com>
- Date
- Oct 12, 2008, 18:18 UTC
- Message-ID
- <20081012181836.GA10626@steel.home>
- In-Reply-To
- <20081012135048.GC21650@dpotapov.dyndns.org>
Dmitry Potapov, Sun, Oct 12, 2008 15:50:48 +0200:
Show 29 quoted lines
> On Sun, Oct 12, 2008 at 12:58:52AM +0200, Alex Riesen wrote:
> > 2008/10/11 Dmitry Potapov <dpotapov@gmail.com>:
> > >> > + /* On Windows, file names are case-insensitive */
> > >> > + case 'G':
> > >> > + if ((rest[1]|0x20) != 'i')
> > >> > + break;
> > >> > + if ((rest[2]|0x20) != 't')
> > >> > + break;
> > >>
> > >> We have tolower().
> > >
> > > I am aware of that, but I am not sure what we gain by using it. It seems
> > > it makes only code bigger and slow.
> >
> > It does? Care to look into git-compat-util.h?
>
> As a matter of fact, I did, and I see the following:
>
> #define sane_istest(x,mask) ((sane_ctype[(unsigned char)(x)] & (mask)) != 0)
> #define tolower(x) sane_case((unsigned char)(x), 0x20)
>
> static inline int sane_case(int x, int high)
> {
> if (sane_istest(x, GIT_ALPHA))
> x = (x & ~0x20) | high;
> return x;
> }
>
> So, it looks like an extra look up and an extra comparison here.Does not look like much more code. But:
Show 8 quoted lines
> > BTW, is it such a critical path? > > I am not sure whether it is critical or not. It is called for each > name in path. So, if you have a long path, it may be called quite a > few times per a single path. Also, some operation such 'git add' can > call verify_path() more than once (IIRC, it was called thrice per each > added file). But I have no numbers to tell whether it is noticeable or > not.
I looked at the callers (briefly). Performance could be a problem: add and checkout can work with real big file lists and long pathnames. So ok, than. It is critical.