From 99f22182c2be0a6d02204b40f8f792f36d31c745 Mon Sep 17 00:00:00 2001 From: Simon Glass Date: Wed, 7 Sep 2016 16:01:55 -0600 Subject: [PATCH] Add DIV_ROUND_CLOSEST Bring in this useful function from Linux 4.7. BUG=chrome-os-partner:56556 BRANCH=none TEST=build on gru Change-Id: I37617e35b4784d6cdc51e6910aa91f566caf971d Signed-off-by: Simon Glass Reviewed-on: https://chromium-review.googlesource.com/382320 Reviewed-by: Julius Werner --- src/include/stdlib.h | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/src/include/stdlib.h b/src/include/stdlib.h index d6e7fafb25..6200f1c590 100644 --- a/src/include/stdlib.h +++ b/src/include/stdlib.h @@ -16,6 +16,22 @@ static inline unsigned long div_round_up(unsigned int n, unsigned int d) { return (n + d - 1) / d; } + +/* + * Divide positive or negative dividend by positive divisor and round + * to closest integer. Result is undefined for negative divisors and + * for negative dividends if the divisor variable type is unsigned. + */ +#define DIV_ROUND_CLOSEST(x, divisor)( \ +{ \ + typeof(x) __x = x; \ + typeof(divisor) __d = divisor; \ + (((typeof(x))-1) > 0 || \ + ((typeof(divisor))-1) > 0 || (__x) > 0) ? \ + (((__x) + ((__d) / 2)) / (__d)) : \ + (((__x) - ((__d) / 2)) / (__d)); \ +} \ +) #endif