Oct 23 2012

[media] dvb-frontends: 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/dvb-frontends/cx24116.c   | 2 +-
 drivers/media/dvb-frontends/drxd_hard.c | 5 ++---
 drivers/media/dvb-frontends/stv0299.c   | 2 +-
 3 files changed, 4 insertions(+), 5 deletions(-)
 
diff --git a/drivers/media/dvb-frontends/cx24116.c b/drivers/media/dvb-frontends/cx24116.c
index b488791..2916d7c 100644
--- a/drivers/media/dvb-frontends/cx24116.c
+++ b/drivers/media/dvb-frontends/cx24116.c
@@ -819,7 +819,7 @@ static int cx24116_read_ucblocks(struct dvb_frontend *fe, u32 *ucblocks)
 static void cx24116_clone_params(struct dvb_frontend *fe)
 {
 	struct cx24116_state *state = fe->demodulator_priv;
-	memcpy(&state->dcur, &state->dnxt, sizeof(state->dcur));
+	state->dcur = state->dnxt;
 }
 
 /* Wait for LNB */
diff --git a/drivers/media/dvb-frontends/drxd_hard.c b/drivers/media/dvb-frontends/drxd_hard.c
index 487c53b..9a213479 100644
--- a/drivers/media/dvb-frontends/drxd_hard.c
+++ b/drivers/media/dvb-frontends/drxd_hard.c
@@ -2965,7 +2965,7 @@ struct dvb_frontend *drxd_attach(const struct drxd_config *config,
 		return NULL;
 	memset(state, 0, sizeof(*state));
 
-	memcpy(&state->ops, &drxd_ops, sizeof(struct dvb_frontend_ops));
+	state->ops = drxd_ops;
 	state->dev = dev;
 	state->config = *config;
 	state->i2c = i2c;
@@ -2976,8 +2976,7 @@ struct dvb_frontend *drxd_attach(const struct drxd_config *config,
 	if (Read16(state, 0, 0, 0) < 0)
 		goto error;
 
-	memcpy(&state->frontend.ops, &drxd_ops,
-	       sizeof(struct dvb_frontend_ops));
+	state->frontend.ops = drxd_ops;
 	state->frontend.demodulator_priv = state;
 	ConfigureMPEGOutput(state, 0);
 	/* add few initialization to allow gate control */
diff --git a/drivers/media/dvb-frontends/stv0299.c b/drivers/media/dvb-frontends/stv0299.c
index 92a6075..b57ecf4 100644
--- a/drivers/media/dvb-frontends/stv0299.c
+++ b/drivers/media/dvb-frontends/stv0299.c
@@ -420,7 +420,7 @@ static int stv0299_send_legacy_dish_cmd (struct dvb_frontend* fe, unsigned long
 
 	do_gettimeofday (&nexttime);
 	if (debug_legacy_dish_switch)
-		memcpy (&tv[0], &nexttime, sizeof (struct timeval));
+		tv[0] = nexttime;
 	stv0299_writeregI (state, 0x0c, reg0x0c | 0x50); /* set LNB to 18V */
 
 	dvb_frontend_sleep_until(&nexttime, 32000);

qlambert