Oct 23 2012

[media] sn9c102: Replace memcpy with struct assignment 

Author: Ezequiel Garcia <elezegarcia@gmail.com>

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

Signed-off-by: Peter Senna Tschudin 
Signed-off-by: Ezequiel Garcia 
Signed-off-by: Mauro Carvalho Chehab 

---
 drivers/media/usb/sn9c102/sn9c102_core.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
 
diff --git a/drivers/media/usb/sn9c102/sn9c102_core.c b/drivers/media/usb/sn9c102/sn9c102_core.c
index 6bda81a..c957e9a 100644
--- a/drivers/media/usb/sn9c102/sn9c102_core.c
+++ b/drivers/media/usb/sn9c102/sn9c102_core.c
@@ -2827,7 +2827,7 @@ 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;
@@ -2930,7 +2930,7 @@ 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;

qlambert