[skalibs] long_fmt fails with FMT_LEN (was: Why no negative numbers in the *_fmt routines?)

[Lloyd Zusman <ljz@asfast.com>]

Lloyd Zusman <ljz <at> asfast.com> writes:

> Lloyd Zusman <ljz <at> asfast.com> writes:
> 
> > [ ... ]
> > the integer-based *_fmt routines do not format negative numbers.
> 
> I'm sorry. I missed long_fmt.c and I misread fmtscan.h. I was getting
> errors with negative numbers, and I mistakenly thought that this was
> due to int_fmt failing with values < 0.

Actually, this problem is due to a bug in long_fmt. It doesn't properly
handle the FMT_LEN argument when the value to be formatted is negative.
This is evident in the source code:

unsigned int long_fmt (char *fmt, long n)
{
  if (n >= 0) return ulong_fmt(fmt, n) ;
  *fmt++ = '-' ;
  return 1 + ulong_fmt(fmt, -n) ;
}

This should be changed as follows:

unsigned int long_fmt (char *fmt, long n)
{
  if (n >= 0) return ulong_fmt(fmt, n) ;
  if (fmt != 0) *fmt++ = '-' ;
  return 1 + ulong_fmt(fmt, -n) ;
}

-- 
 Lloyd Zusman
 ljz@asfast.com
 God bless you.