linux/lib/lcm.c
Rasmus Villemoes 74a5fef7cb lib/lcm.c: ensure correct result whenever it fits
Ensure that lcm(a,b) returns the mathematically correct result, provided
it fits in an unsigned long.  The current version returns garbage if a*b
overflows, even if the final result would fit.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-12-10 17:41:11 -08:00

17 lines
288 B
C

#include <linux/kernel.h>
#include <linux/gcd.h>
#include <linux/export.h>
#include <linux/lcm.h>
/* Lowest common multiple */
unsigned long lcm(unsigned long a, unsigned long b)
{
if (a && b)
return (a / gcd(a, b)) * b;
else if (b)
return b;
return a;
}
EXPORT_SYMBOL_GPL(lcm);