linux/lib/gcd.c
Davidlohr Bueso e96875677f lib/gcd.c: prevent possible div by 0
Account for all properties when a and/or b are 0:
gcd(0, 0) = 0
gcd(a, 0) = a
gcd(0, b) = b

Fixes no known problems in current kernels.

Signed-off-by: Davidlohr Bueso <dave@gnu.org>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-06 03:04:57 +09:00

22 lines
313 B
C

#include <linux/kernel.h>
#include <linux/gcd.h>
#include <linux/export.h>
/* Greatest common divisor */
unsigned long gcd(unsigned long a, unsigned long b)
{
unsigned long r;
if (a < b)
swap(a, b);
if (!b)
return a;
while ((r = a % b) != 0) {
a = b;
b = r;
}
return b;
}
EXPORT_SYMBOL_GPL(gcd);