path: root/sound/core/pcm.c
diff options
authorJulia Lawall <julia@diku.dk>2009-10-17 08:33:22 +0200
committerTakashi Iwai <tiwai@suse.de>2009-10-30 12:01:27 +0100
commit4b3be6afa4ab8b3fdce39df68bad71f8b85164de (patch)
tree9022bd2b563fabc987e31277782076db42946bb7 /sound/core/pcm.c
parentb71207e9dc044b30d8b5d7f1c2290ba14563f05c (diff)
ALSA: sound: Move dereference after NULL test and drop unnecessary NULL tests
In pcm.c, if the NULL test on pcm is needed, then the dereference should be after the NULL test. In dummy.c and ali5451.c, the context of the calls to snd_card_dummy_new_mixer and snd_ali_free_voice show that dummy and pvoice, respectively cannot be NULL. A simplified version of the semantic match that detects this problem is as follows (http://coccinelle.lip6.fr/): // <smpl> @match exists@ expression x, E; identifier fld; @@ * x->fld ... when != \(x = E\|&x\) * x == NULL // </smpl> Signed-off-by: Julia Lawall <julia@diku.dk> Signed-off-by: Takashi Iwai <tiwai@suse.de>
Diffstat (limited to 'sound/core/pcm.c')
1 files changed, 3 insertions, 2 deletions
diff --git a/sound/core/pcm.c b/sound/core/pcm.c
index 0c1440121c22..c69c60b2a48a 100644
--- a/sound/core/pcm.c
+++ b/sound/core/pcm.c
@@ -953,11 +953,12 @@ static int snd_pcm_dev_register(struct snd_device *device)
struct snd_pcm_substream *substream;
struct snd_pcm_notify *notify;
char str[16];
- struct snd_pcm *pcm = device->device_data;
+ struct snd_pcm *pcm;
struct device *dev;
- if (snd_BUG_ON(!pcm || !device))
+ if (snd_BUG_ON(!device || !device->device_data))
return -ENXIO;
+ pcm = device->device_data;
err = snd_pcm_add(pcm);
if (err) {