lib/libc/strings/ffs.c


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int ffs(int i)
{
	if (i == 0) {
		return 0;
	}

	int pos = 1;
	unsigned int u = (unsigned int)i;

	while ((u & 1U) == 0U) {
		u >>= 1;
		pos++;
	}

	return pos;
}