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| -rw-r--r-- | include/common.h | 10 |
1 files changed, 10 insertions, 0 deletions
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 |