Re: I created a faster JSON parser

[Herman , Géza]

Eli Zaretskii <eliz@gnu.org> writes:

> > From: Herman, Géza <geza.herman@gmail.com>
> > Cc: Géza Herman <geza.herman@gmail.com>,
> >  emacs-devel@gnu.org
> > Date: Fri, 08 Mar 2024 14:12:19 +0100
> The following is based on an initial reading of the patch:
>
>  . Redundant braces (for blocks of a single code line) is one 
>  issue.
>  . The way you break a long line at the equals sign '=' is 
>  another (we
>    break after '=', not before).
I used clang-format to format my code (I use a completely 
different coding style).  I see that clang-format is configured 
this way in Emacs.  Shouldn't BreakBeforeBinaryOperators be set to 
None or NonAssignment in .clang-format?

>  . The code which handles integers seems to assume that 
>  'unsigned long'
>    is a 64-bit type? if so, this is not true on Windows; please 
>    see how
>    we handle this elsewhere in Emacs, in particular in the
>    WIDE_EMACS_INT case.
That was a mistake on my part, though a different (but similar) 
one.  I originally used a 64-bit type, but then changed it to 
long, because of 32-bit architectures.  The idea is to use a type 
which likely has the same size as a CPU register.  So I think long 
is OK, I just need to change the thresholds to ULONG_MAX.  Or I 
think I'll use ckd_* functions as Collin suggested.

> A more general comment is that you seem to be parsing buffer 
> text
> assuming it's UTF-8?  If so, this is not accurate, as the 
> internal
> representation is a superset of UTF-8, and can represent 
> characters
> above 0x10FFFF.
When does a buffer have characters above 0x10ffff?  I supposed 
that a JSON shouldn't contain characters that are out of range. 
But if the solution is to just remove the upper-range comparison, 
I can do that easily.

> > Can you please send me the necessary documents?
>
> Sent off-list.
Thanks!