linux-kernel - [PATCH 2/5] drivers/media/video/uvc: Use DIV_ROUND

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Date:	Sat, 1 Aug 2009 21:49:04 +0200 (CEST)
From:	Julia Lawall <julia@...u.dk>
To:	laurent.pinchart@...net.be, linux-media@...r.kernel.org,
	linux-uvc-devel@...ts.berlios.de, linux-kernel@...r.kernel.org,
	kernel-janitors@...r.kernel.org
Subject: [PATCH 2/5] drivers/media/video/uvc: Use DIV_ROUND_CLOSEST

From: Julia Lawall <julia@...u.dk>

The kernel.h macro DIV_ROUND_CLOSEST performs the computation (x + d/2)/d
but is perhaps more readable.

The semantic patch that makes this change is as follows:
(http://www.emn.fr/x-info/coccinelle/)

// <smpl>
@haskernel@
@@

#include <linux/kernel.h>

@depends on haskernel@
expression x,__divisor;
@@

- (((x) + ((__divisor) / 2)) / (__divisor))
+ DIV_ROUND_CLOSEST(x,__divisor)
// </smpl>

Signed-off-by: Julia Lawall <julia@...u.dk>

---
 drivers/media/video/uvc/uvc_v4l2.c  |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/drivers/media/video/uvc/uvc_v4l2.c b/drivers/media/video/uvc/uvc_v4l2.c
index 87cb9cc..6edaaf6 100644
--- a/drivers/media/video/uvc/uvc_v4l2.c
+++ b/drivers/media/video/uvc/uvc_v4l2.c
@@ -95,7 +95,7 @@ static __u32 uvc_try_frame_interval(struct uvc_frame *frame, __u32 interval)
 		const __u32 max = frame->dwFrameInterval[1];
 		const __u32 step = frame->dwFrameInterval[2];
 
-		interval = min + (interval - min + step/2) / step * step;
+		interval = min + DIV_ROUND_CLOSEST(interval-min, step) * step;
 		if (interval > max)
 			interval = max;
 	}
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/