[alsa-devel] [PATCH - UCM 1/1] ucm: add binary configure file parse

[Takashi Iwai]

At Tue, 20 Jan 2015 16:33:09 +0800,
han.lu at intel.com wrote:
> 
> From: "Lu, Han" <han.lu at intel.com>
> 
> with cset command, UCM set kcontrol parameters directly:
>     cset "name='<KCONTROL_NAME>' 1<,2,3,...>"
> This patch enables UCM to set kcontrol with parameters from
> configure file:
>     cset-bin-file "name='<KCONTROL_NAME>' <path/to/file>"
> where "cset-bin-file" is a newly added keyword alongside of "cset",
> to indicate cset with binary data in file.
> The binary data in file is parameter for audio DSPs, and it's just
> passed by UCM/ALSA as raw data. The data type of the parameter
> element must be byte, and the count is limited by the size of
> struct snd_ctl_elem_value and driver definition.
> 
> Signed-off-by: Lu, Han <han.lu at intel.com>
> 
> diff --git a/src/ucm/main.c b/src/ucm/main.c
> index 37ae4c8..818465a 100644
> --- a/src/ucm/main.c
> +++ b/src/ucm/main.c
> @@ -160,11 +160,62 @@ static int open_ctl(snd_use_case_mgr_t *uc_mgr,
>  	return 0;
>  }
>  
> +static int binary_file_parse(snd_ctl_elem_value_t *dst,
> +			      snd_ctl_elem_info_t *info,
> +			      const char *filepath)
> +{
> +	int err, fd;
> +	struct stat st;
> +	size_t sz;
> +	char *res;
> +	snd_ctl_elem_type_t type;
> +	unsigned int idx, count;
> +
> +	type = snd_ctl_elem_info_get_type(info);
> +	if (type != SND_CTL_ELEM_TYPE_BYTES) {
> +		uc_error("only support byte type!");
> +		err = -EINVAL;
> +		return err;
> +	}
> +	fd = open(filepath, O_RDONLY);
> +	if (fd < 0) {
> +		err = -errno;
> +		return err;
> +	}
> +	if (stat(filepath, &st) == -1) {
> +		err = -errno;
> +		goto __fail;
> +	}
> +	sz = st.st_size;
> +	count = snd_ctl_elem_info_get_count(info);
> +	if (sz == 0 || sz > count || sz > sizeof(dst->value.bytes)) {
> +		uc_error("invalid parameter size!");

A question here is what if the file size is smaller than the expected
data size.  Should we allow this explicitly?  I thought it'd be safer
to bail out, but I'd like to know more about the scenarios behind this
patch.

> +		err = -EINVAL;
> +		goto __fail;
> +	}
> +	res = calloc(sz, 1);

This can be malloc() as we'll overwrite the whole data in anyway.


thanks,

Takashi

> +	if (res == NULL) {
> +		err = -ENOMEM;
> +		goto __fail;
> +	}
> +	if (read(fd, res, sz) != sz) {
> +		err = -errno;
> +		goto __fail_read;
> +	}
> +	for (idx = 0; idx < sz; idx++)
> +		snd_ctl_elem_value_set_byte(dst, idx, *(res + idx));
> +      __fail_read:
> +	free(res);
> +      __fail:
> +	close(fd);
> +	return err;
> +}
> +
>  extern int __snd_ctl_ascii_elem_id_parse(snd_ctl_elem_id_t *dst,
>  					 const char *str,
>  					 const char **ret_ptr);
>  
> -static int execute_cset(snd_ctl_t *ctl, const char *cset)
> +static int execute_cset(snd_ctl_t *ctl, const char *cset, unsigned int type)
>  {
>  	const char *pos;
>  	int err;
> @@ -194,7 +245,10 @@ static int execute_cset(snd_ctl_t *ctl, const char *cset)
>  	err = snd_ctl_elem_info(ctl, info);
>  	if (err < 0)
>  		goto __fail;
> -	err = snd_ctl_ascii_value_parse(ctl, value, info, pos);
> +	if (type == SEQUENCE_ELEMENT_TYPE_CSET_BIN_FILE)
> +		err = binary_file_parse(value, info, pos);
> +	else
> +		err = snd_ctl_ascii_value_parse(ctl, value, info, pos);
>  	if (err < 0)
>  		goto __fail;
>  	err = snd_ctl_elem_write(ctl, value);
> @@ -239,6 +293,7 @@ static int execute_sequence(snd_use_case_mgr_t *uc_mgr,
>  				goto __fail_nomem;
>  			break;
>  		case SEQUENCE_ELEMENT_TYPE_CSET:
> +		case SEQUENCE_ELEMENT_TYPE_CSET_BIN_FILE:
>  			if (cdev == NULL) {
>  				const char *cdev1 = NULL, *cdev2 = NULL;
>  				err = get_value3(&cdev1, "PlaybackCTL",
> @@ -274,7 +329,7 @@ static int execute_sequence(snd_use_case_mgr_t *uc_mgr,
>  					goto __fail;
>  				}
>  			}
> -			err = execute_cset(ctl, s->data.cset);
> +			err = execute_cset(ctl, s->data.cset, s->type);
>  			if (err < 0) {
>  				uc_error("unable to execute cset '%s'\n", s->data.cset);
>  				goto __fail;
> diff --git a/src/ucm/parser.c b/src/ucm/parser.c
> index d7517f6..9e1cb41 100644
> --- a/src/ucm/parser.c
> +++ b/src/ucm/parser.c
> @@ -306,6 +306,16 @@ static int parse_sequence(snd_use_case_mgr_t *uc_mgr ATTRIBUTE_UNUSED,
>  			continue;
>  		}
>  
> +		if (strcmp(cmd, "cset-bin-file") == 0) {
> +			curr->type = SEQUENCE_ELEMENT_TYPE_CSET_BIN_FILE;
> +			err = parse_string(n, &curr->data.cset);
> +			if (err < 0) {
> +				uc_error("error: cset-bin-file requires a string!");
> +				return err;
> +			}
> +			continue;
> +		}
> +
>  		if (strcmp(cmd, "usleep") == 0) {
>  			curr->type = SEQUENCE_ELEMENT_TYPE_SLEEP;
>  			err = snd_config_get_integer(n, &curr->data.sleep);
> diff --git a/src/ucm/ucm_local.h b/src/ucm/ucm_local.h
> index 87f14a2..c1655c7 100644
> --- a/src/ucm/ucm_local.h
> +++ b/src/ucm/ucm_local.h
> @@ -47,6 +47,7 @@
>  #define SEQUENCE_ELEMENT_TYPE_CSET	2
>  #define SEQUENCE_ELEMENT_TYPE_SLEEP	3
>  #define SEQUENCE_ELEMENT_TYPE_EXEC	4
> +#define SEQUENCE_ELEMENT_TYPE_CSET_BIN_FILE	5
>  
>  struct ucm_value {
>          struct list_head list;
> -- 
> 2.1.0
>