Re: [PATCH]: grub: Fix handling of long printf arguments on 64-bit.

[Yoshinori K. Okuji]

On Saturday 11 April 2009 17:08:29 David Miller wrote:
> The grub printf code tries to treat 'long' and 'int' the same,
> that doesn't work on (most) 64-bit platforms.

Right. Good finding.

Regards,
Okuji

>
> 2009-04-11  David S. Miller  <address@hidden>
>
>       * kern/misc.c (grub_ltoa): New function.
>       (grub_vsprintf): Use it to format 'long' integers.
> ---
>  kern/misc.c |   35 +++++++++++++++++++++++++++++++----
>  1 files changed, 31 insertions(+), 4 deletions(-)
>
> diff --git a/kern/misc.c b/kern/misc.c
> index 23eaa14..85a5d95 100644
> --- a/kern/misc.c
> +++ b/kern/misc.c
> @@ -590,6 +590,31 @@ grub_itoa (char *str, int c, unsigned n)
>    return p;
>  }
>
> +static char *
> +grub_ltoa (char *str, int c, unsigned long n)
> +{
> +  unsigned long base = (c == 'x') ? 16 : 10;
> +  char *p;
> +
> +  if ((long) n < 0 && c == 'd')
> +    {
> +      n = (unsigned) (-((long) n));
> +      *str++ = '-';
> +    }
> +
> +  p = str;
> +  do
> +    {
> +      unsigned long d = n % base;
> +      *p++ = (d > 9) ? d + 'a' - 10 : d + '0';
> +    }
> +  while (n /= base);
> +  *p = 0;
> +
> +  grub_reverse (str);
> +  return p;
> +}
> +
>  /* Divide N by D, return the quotient, and store the remainder in *R.  */
>  grub_uint64_t
>  grub_divmod64 (grub_uint64_t n, grub_uint32_t d, grub_uint32_t *r)
> @@ -790,12 +815,14 @@ grub_vsprintf (char *str, const char *fmt, va_list
> args) ll = va_arg (args, long long);
>                 grub_lltoa (tmp, c, ll);
>               }
> +           else if (longfmt)
> +             {
> +               long l = va_arg (args, long);
> +               grub_ltoa (tmp, c, l);
> +             }
>             else
>               {
> -               if (longfmt)
> -                 n = va_arg (args, long);
> -               else
> -                 n = va_arg (args, int);
> +               n = va_arg (args, int);
>                 grub_itoa (tmp, c, n);
>               }
>             if (! rightfill && grub_strlen (tmp) < format1)