conf: remove alloca() from snd_func_card_id()

Both of alloca() and automatic variables keeps storages on stack, while
the former generates more instructions than the latter. It's better to use
the latter if the size of storage is computable at pre-compile or compile
time; i.e. just for structures.

This commit obsolete usages of alloca() with automatic variables.

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

diff --git a/src/confmisc.c b/src/confmisc.c
index 3f12e340c46d00163b254b3fb2c3a70f9dea59ba..7763511b887d76872aee0e2332a2f23fa832ccf1 100644 (file)
--- a/src/confmisc.c
+++ b/src/confmisc.c
@@ -862,7 +862,7 @@ int snd_func_card_id(snd_config_t **dst, snd_config_t *root, snd_config_t *src,
                     snd_config_t *private_data)
 {
        snd_ctl_t *ctl = NULL;
-       snd_ctl_card_info_t *info;
+       snd_ctl_card_info_t info = {0};
        const char *id;
        int card, err;
        
@@ -874,8 +874,7 @@ int snd_func_card_id(snd_config_t **dst, snd_config_t *root, snd_config_t *src,
                SNDERR("could not open control for card %i", card);
                goto __error;
        }
-       snd_ctl_card_info_alloca(&info);
-       err = snd_ctl_card_info(ctl, info);
+       err = snd_ctl_card_info(ctl, &info);
        if (err < 0) {
                SNDERR("snd_ctl_card_info error: %s", snd_strerror(err));
                goto __error;
@@ -883,7 +882,7 @@ int snd_func_card_id(snd_config_t **dst, snd_config_t *root, snd_config_t *src,
        err = snd_config_get_id(src, &id);
        if (err >= 0)
                err = snd_config_imake_string(dst, id,
-                                             snd_ctl_card_info_get_id(info));
+                                             snd_ctl_card_info_get_id(&info));
       __error:
        if (ctl)
                snd_ctl_close(ctl);