Re: novice coding in /linux/net/ipv4/util.c From: DJ Barrow <dj.barrow@asitatech.com>

From: DJ Barrow (dj.barrow@asitatech.com)
Date: Mon Apr 22 2002 - 11:03:50 EST


Richard,
I agree The least offensive way would be to pass in a sring from the caller,
I didn't spot the second endian bug till you mentioned it ;-).

I wish Linus would finally get rid of the errno global as this is equally
stupid on smp machines or else make an errno_array[NR_CPUS] array
& make errno a #define errno errno_array[smp_processor_id()] or
something similar, plenty of others have posted patches for that
rubbish.

Alan Cox is on the list of Authors, he must have wrote it ;-)

On Monday 22 April 2002 16:48, Richard B. Johnson wrote:
> On Mon, 22 Apr 2002, DJ Barrow wrote:
> > Hi ,
> > While debugging last night with Brian O'Sullivan I found this beauty.
> >
> > char *in_ntoa(__u32 in)
> > {
> > static char buff[18];
> > char *p;
> >
> > p = (char *) &in;
> > sprintf(buff, "%d.%d.%d.%d",
> > (p[0] & 255), (p[1] & 255), (p[2] & 255), (p[3] & 255));
> > return(buff);
> > }
> >
> > This textbook peice of novice coding which has existed since 2.2.14.
> > For those who can't spot the error, please note that this function is
> > returning a static string, excellent stuff if you are hoping to reuse the
> > same function like the following
> > printk("%s %s\n",in_ntoa(addr1),in_ntoa(addr2));
> > -
>
> I love it! Last guy wins! I wonder how you fix it without having to
> pass it a pointer to something the caller owns? This is, truly,
> non-trivial. Also, this is in ../linux/net, not something specific
> to Intel, and there is no macro to handle the network-order. It
> just 'comes-out-right' with Intel machines.
>
> Cheers,
> Dick Johnson
>
> Penguin : Linux version 2.4.18 on an i686 machine (797.90 BogoMips).
>
> Windows-2000/Professional isn't.-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/



This archive was generated by hypermail 2b29 : Tue Apr 23 2002 - 22:00:31 EST