From 23b99432e59b4ee994888f7bd8ef1f77bb424756 Mon Sep 17 00:00:00 2001 From: Richard Weinberger Date: Thu, 18 Oct 2018 16:36:38 +0200 Subject: common: Add round functions Signed-off-by: Richard Weinberger Signed-off-by: David Oberhollenzer --- include/common.h | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/include/common.h b/include/common.h index 2f24645..7270769 100644 --- a/include/common.h +++ b/include/common.h @@ -65,6 +65,16 @@ extern "C" { (_x > _y) ? _x : _y; \ }) +/* + * This looks more complex than it should be. But we need to + * get the type for the ~ right in round_down (it needs to be + * as wide as the result!), and we want to evaluate the macro + * arguments just once each. + */ +#define __round_mask(x, y) ((__typeof__(x))((y)-1)) +#define round_up(x, y) ((((x)-1) | __round_mask(x, y))+1) +#define round_down(x, y) ((x) & ~__round_mask(x, y)) + #ifndef O_CLOEXEC #define O_CLOEXEC 0 #endif -- cgit v1.2.3