Re: [PATCH 08/23] cx25840: Replace memcpy with struct assignment

Andy Walls
2012-10-23T22:20:23Z

On Tue, 2012-10-23 at 16:57 -0300, 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.
>
> 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>
>

This patch is fine.

Signed-off-by: Andy Walls <awalls@md.metrocast.net>

> Signed-off-by: Peter Senna Tschudin <peter.senna@gmail.com>
> Signed-off-by: Ezequiel Garcia <elezegarcia@gmail.com>
> ---
> drivers/media/i2c/cx25840/cx25840-ir.c | 6 ++----
> 1 files changed, 2 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/media/i2c/cx25840/cx25840-ir.c b/drivers/media/i2c/cx25840/cx25840-ir.c
> index 38ce76e..9ae977b 100644
> --- a/drivers/media/i2c/cx25840/cx25840-ir.c
> +++ b/drivers/media/i2c/cx25840/cx25840-ir.c
> @@ -1251,13 +1251,11 @@ int cx25840_ir_probe(struct v4l2_subdev *sd)
> cx25840_write4(ir_state->c, CX25840_IR_IRQEN_REG, 0);
>
> mutex_init(&ir_state->rx_params_lock);
> - memcpy(&default_params, &default_rx_params,
> - sizeof(struct v4l2_subdev_ir_parameters));
> + default_params = default_rx_params;
> v4l2_subdev_call(sd, ir, rx_s_parameters, &default_params);
>
> mutex_init(&ir_state->tx_params_lock);
> - memcpy(&default_params, &default_tx_params,
> - sizeof(struct v4l2_subdev_ir_parameters));
> + default_params = default_tx_params;
> v4l2_subdev_call(sd, ir, tx_s_parameters, &default_params);
>
> return 0;