[PATCH 2/2] ubi-utils: ubiformat.c: convert to integer arithmetic

Andrea Adami andrea.adami at gmail.com
Thu Jan 25 00:52:38 PST 2018


Do not cast percent to double, it is just used as upper limit.
Avoid floating point to fix compilation for aarch64 against klibc:

error: '-mgeneral-regs-only' is incompatible with floating-point code
|    int percent = ((double)si->ok_cnt)/si->good_cnt * 100;
|        ^~~~~~~

Notes:
* The checks in the code above this line ensure that si->good_cnt is not 0.

* The code assumes  si->good_cnt * 100  will not overflow, then we can use
  (si->ok_cnt * 100) safely because the former is bigger.

* The truncated result does not affect the logic:
  i.e. a value of 49.9 is truncated to 49 and is still <50.

Signed-off-by: Andrea Adami <andrea.adami at gmail.com>
---
 ubi-utils/ubiformat.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/ubi-utils/ubiformat.c b/ubi-utils/ubiformat.c
index ef0378a..c38b9b4 100644
--- a/ubi-utils/ubiformat.c
+++ b/ubi-utils/ubiformat.c
@@ -844,7 +844,7 @@ int main(int argc, char * const argv[])
 	}
 
 	if (!args.override_ec && si->empty_cnt < si->good_cnt) {
-		int percent = ((double)si->ok_cnt)/si->good_cnt * 100;
+		int percent = (si->ok_cnt * 100) / si->good_cnt;
 
 		/*
 		 * Make sure the majority of eraseblocks have valid
-- 
2.7.4




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