[PATCH v2] uvc: Replace memcpy with struct assignment

[PATCH v2] uvc: Replace memcpy with struct assignment

[Ezequiel Garcia]

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.

Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Peter Senna Tschudin <peter.senna@gmail.com>
Signed-off-by: Ezequiel Garcia <elezegarcia@gmail.com>
---
Changes from v1: 
 * Replaced a memcpy() in ucv_ctrl_add_info(),
   originally missed by the coccinelle script.

 drivers/media/usb/uvc/uvc_ctrl.c |    2 +-
 drivers/media/usb/uvc/uvc_v4l2.c |    6 +++---
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/media/usb/uvc/uvc_ctrl.c b/drivers/media/usb/uvc/uvc_ctrl.c
index 516a5b1..f2f6443 100644
--- a/drivers/media/usb/uvc/uvc_ctrl.c
+++ b/drivers/media/usb/uvc/uvc_ctrl.c
@@ -1839,7 +1839,7 @@ static int uvc_ctrl_add_info(struct uvc_device *dev, struct uvc_control *ctrl,
 {
 	int ret = 0;
 
-	memcpy(&ctrl->info, info, sizeof(*info));
+	ctrl->info = *info;
 	INIT_LIST_HEAD(&ctrl->info.mappings);
 
 	/* Allocate an array to save control values (cur, def, max, etc.) */
diff --git a/drivers/media/usb/uvc/uvc_v4l2.c b/drivers/media/usb/uvc/uvc_v4l2.c
index 8e05604..36e79ed 100644
--- a/drivers/media/usb/uvc/uvc_v4l2.c
+++ b/drivers/media/usb/uvc/uvc_v4l2.c
@@ -315,7 +315,7 @@ static int uvc_v4l2_set_format(struct uvc_streaming *stream,
 		goto done;
 	}
 
-	memcpy(&stream->ctrl, &probe, sizeof probe);
+	stream->ctrl = probe;
 	stream->cur_format = format;
 	stream->cur_frame = frame;
 
@@ -387,7 +387,7 @@ static int uvc_v4l2_set_streamparm(struct uvc_streaming *stream,
 		return -EBUSY;
 	}
 
-	memcpy(&probe, &stream->ctrl, sizeof probe);
+	probe = stream->ctrl;
 	probe.dwFrameInterval =
 		uvc_try_frame_interval(stream->cur_frame, interval);
 
@@ -398,7 +398,7 @@ static int uvc_v4l2_set_streamparm(struct uvc_streaming *stream,
 		return ret;
 	}
 
-	memcpy(&stream->ctrl, &probe, sizeof probe);
+	stream->ctrl = probe;
 	mutex_unlock(&stream->mutex);
 
 	/* Return the actual frame period. */
-- 
1.7.4.4

Re: [PATCH v2] uvc: Replace memcpy with struct assignment

[Laurent Pinchart]

Hi,

On Monday 14 January 2013 15:22:55 Ezequiel Garcia wrote:
> 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.
> 
> Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> Signed-off-by: Peter Senna Tschudin <peter.senna@gmail.com>
> Signed-off-by: Ezequiel Garcia <elezegarcia@gmail.com>

Thank you for the patch. I've applied it to my tree.

> ---
> Changes from v1:
>  * Replaced a memcpy() in ucv_ctrl_add_info(),
>    originally missed by the coccinelle script.
> 
>  drivers/media/usb/uvc/uvc_ctrl.c |    2 +-
>  drivers/media/usb/uvc/uvc_v4l2.c |    6 +++---
>  2 files changed, 4 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/media/usb/uvc/uvc_ctrl.c
> b/drivers/media/usb/uvc/uvc_ctrl.c index 516a5b1..f2f6443 100644
> --- a/drivers/media/usb/uvc/uvc_ctrl.c
> +++ b/drivers/media/usb/uvc/uvc_ctrl.c
> @@ -1839,7 +1839,7 @@ static int uvc_ctrl_add_info(struct uvc_device *dev,
> struct uvc_control *ctrl, {
>  	int ret = 0;
> 
> -	memcpy(&ctrl->info, info, sizeof(*info));
> +	ctrl->info = *info;
>  	INIT_LIST_HEAD(&ctrl->info.mappings);
> 
>  	/* Allocate an array to save control values (cur, def, max, etc.) */
> diff --git a/drivers/media/usb/uvc/uvc_v4l2.c
> b/drivers/media/usb/uvc/uvc_v4l2.c index 8e05604..36e79ed 100644
> --- a/drivers/media/usb/uvc/uvc_v4l2.c
> +++ b/drivers/media/usb/uvc/uvc_v4l2.c
> @@ -315,7 +315,7 @@ static int uvc_v4l2_set_format(struct uvc_streaming
> *stream, goto done;
>  	}
> 
> -	memcpy(&stream->ctrl, &probe, sizeof probe);
> +	stream->ctrl = probe;
>  	stream->cur_format = format;
>  	stream->cur_frame = frame;
> 
> @@ -387,7 +387,7 @@ static int uvc_v4l2_set_streamparm(struct uvc_streaming
> *stream, return -EBUSY;
>  	}
> 
> -	memcpy(&probe, &stream->ctrl, sizeof probe);
> +	probe = stream->ctrl;
>  	probe.dwFrameInterval =
>  		uvc_try_frame_interval(stream->cur_frame, interval);
> 
> @@ -398,7 +398,7 @@ static int uvc_v4l2_set_streamparm(struct uvc_streaming
> *stream, return ret;
>  	}
> 
> -	memcpy(&stream->ctrl, &probe, sizeof probe);
> +	stream->ctrl = probe;
>  	mutex_unlock(&stream->mutex);
> 
>  	/* Return the actual frame period. */

-- 
Regards,

Laurent Pinchart