On Sun, Jan 06, 2013 at 11:25:44PM -0500, Nickolai Zeldovich wrote:
> @@ -494,20 +505,15 @@
>
> while (ISDIGIT ((unsigned char)**type))
> {
> - count *= 10;
> -
> - /* Check for overflow.
> - We assume that count is represented using two's-complement;
> - no power of two is divisible by ten, so if an overflow occurs
> - when multiplying by ten, the result will not be a multiple of
> - ten. */
> - if ((count % 10) != 0)
> + /* Check whether we can add another digit without overflow. */
> + if (count > (INT_MAX - 9) / 10)
> {
> while (ISDIGIT ((unsigned char) **type))
> (*type)++;
> return -1;
> }
>
> + count *= 10;
> count += **type - '0';
> (*type)++;
Won't the above preclude parsing 2147483640 up to 2147483647 ?
Because then in the last iteration count 214748364 > (INT_MAX - 9) / 10.
Jakub
