[alsa-devel] [PATCH] control: Allow cset'ing specific values in the multi-value case

[Takashi Iwai]

At Tue,  9 Jun 2015 16:25:07 +0530,
arun at accosted.net wrote:
> 
> From: Arun Raghavan <git at arunraghavan.net>
> 
> This works with syntax like ...
> 
>   amixer cset 'IIR1 Band1'  ,,200
> 
> ... to set the third value of the control to 200.
> ---
>  src/control/ctlparse.c | 10 ++++++----
>  1 file changed, 6 insertions(+), 4 deletions(-)
> 
> diff --git a/src/control/ctlparse.c b/src/control/ctlparse.c
> index 8d6c385..64c6480 100644
> --- a/src/control/ctlparse.c
> +++ b/src/control/ctlparse.c
> @@ -48,9 +48,9 @@ static inline long int convert_prange1(long val, long min, long max)
>  #define check_range(val, min, max) \
>  	((val < min) ? (min) : ((val > max) ? (max) : (val)))
>  
> -static long get_integer(const char **ptr, long min, long max)
> +static long get_integer(const char **ptr, long def, long min, long max)
>  {
> -	long val = min;
> +	long val = def;
>  	char *p = (char *)*ptr, *s;
>  
>  	if (*p == ':')
> @@ -351,6 +351,8 @@ int snd_ctl_ascii_value_parse(snd_ctl_t *handle,
>  			break;
>  		case SND_CTL_ELEM_TYPE_INTEGER:
>  			tmp = get_integer(&ptr,
> +					  snd_ctl_elem_value_get_integer(dst,
> +									 idx),
>  					  snd_ctl_elem_info_get_min(info),
>  					  snd_ctl_elem_info_get_max(info));
>  			snd_ctl_elem_value_set_integer(dst, idx, tmp);
> @@ -364,12 +366,12 @@ int snd_ctl_ascii_value_parse(snd_ctl_t *handle,
>  		case SND_CTL_ELEM_TYPE_ENUMERATED:
>  			tmp = get_ctl_enum_item_index(handle, info, &ptr);
>  			if (tmp < 0)
> -				tmp = get_integer(&ptr, 0,
> +				tmp = get_integer(&ptr, 0, 0,
>  					snd_ctl_elem_info_get_items(info) - 1);
>  			snd_ctl_elem_value_set_enumerated(dst, idx, tmp);
>  			break;
>  		case SND_CTL_ELEM_TYPE_BYTES:
> -			tmp = get_integer(&ptr, 0, 255);
> +			tmp = get_integer(&ptr, 0, 0, 255);
>  			snd_ctl_elem_value_set_byte(dst, idx, tmp);
>  			break;

Hmm, if it's just about skipping the empty element, how about the
patch below instead?


thanks,

Takashi

---
diff --git a/src/control/ctlparse.c b/src/control/ctlparse.c
index 8d6c3859bec4..877a05e3a1f1 100644
--- a/src/control/ctlparse.c
+++ b/src/control/ctlparse.c
@@ -325,6 +325,8 @@ int snd_ctl_ascii_value_parse(snd_ctl_t *handle,
 	snd_ctl_elem_value_set_id(dst, myid);
 	
 	for (idx = 0; idx < count && idx < 128 && ptr && *ptr; idx++) {
+		if (*ptr == ',')
+			goto skip;
 		switch (type) {
 		case SND_CTL_ELEM_TYPE_BOOLEAN:
 			tmp = 0;
@@ -375,6 +377,7 @@ int snd_ctl_ascii_value_parse(snd_ctl_t *handle,
 		default:
 			break;
 		}
+	skip:
 		if (!strchr(value, ','))
 			ptr = value;
 		else if (*ptr == ',')