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From: Ezequiel Garcia <elezegarcia@gmail.com>
To: <linux-kernel@vger.kernel.org>, <linux-media@vger.kernel.org>
Cc: Julia.Lawall@lip6.fr, kernel-janitors@vger.kernel.org,
        Ezequiel Garcia <elezegarcia@gmail.com>,
        Peter Senna Tschudin <peter.senna@gmail.com>
Subject: [PATCH 04/23] sn9c102: Replace memcpy with struct assignment
Date: Tue, 23 Oct 2012 16:57:07 -0300
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This kind of memcpy() is error-prone. Its replacement with a struct
assignment is prefered because it's type-safe and much easier to read.

Found by coccinelle. Hand patched and reviewed.
Tested by compilation only.

A simplified version of the semantic match that finds this problem is as
follows: (http://coccinelle.lip6.fr/)

// <smpl>
@@
identifier struct_name;
struct struct_name to;
struct struct_name from;
expression E;
@@
-memcpy(&(to), &(from), E);
+to = from;
// </smpl>

Signed-off-by: Peter Senna Tschudin <peter.senna@gmail.com>
Signed-off-by: Ezequiel Garcia <elezegarcia@gmail.com>
---
 drivers/media/usb/sn9c102/sn9c102_core.c |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/media/usb/sn9c102/sn9c102_core.c b/drivers/media/usb/sn9c102/sn9c102_core.c
index 5bfc8e2..4cae6f8 100644
--- a/drivers/media/usb/sn9c102/sn9c102_core.c
+++ b/drivers/media/usb/sn9c102/sn9c102_core.c
@@ -2824,7 +2824,7 @@ sn9c102_vidioc_querybuf(struct sn9c102_device* cam, void __user * arg)
 	    b.index >= cam->nbuffers || cam->io != IO_MMAP)
 		return -EINVAL;
 
-	memcpy(&b, &cam->frame[b.index].buf, sizeof(b));
+	b = cam->frame[b.index].buf;
 
 	if (cam->frame[b.index].vma_use_count)
 		b.flags |= V4L2_BUF_FLAG_MAPPED;
@@ -2927,7 +2927,7 @@ sn9c102_vidioc_dqbuf(struct sn9c102_device* cam, struct file* filp,
 
 	f->state = F_UNUSED;
 
-	memcpy(&b, &f->buf, sizeof(b));
+	b = f->buf;
 	if (f->vma_use_count)
 		b.flags |= V4L2_BUF_FLAG_MAPPED;
 
-- 
1.7.4.4