[alsa-devel] [PATCH 5/6] control: add a function to add an element of bytes type

[Takashi Sakamoto]

Hi,

On Feb 23 2016 17:31, Clemens Ladisch wrote:
> Takashi Sakamoto wrote:
>> ALSA Ctl core allows userspace applications to add elements of bytes type,
>> while there's no APIs for this purpose in alsa-lib.
>>
>> This commit adds the missing function.
>
>>   /**
>> + * \brief Create and add an user-defined control element of bytes type.
>> + * \param[in] ctl CTL handle.
>> + * \param[in,out] id ID of the new control element.
>> + * \param[in] channels The number of channels which a control element includes.
>
> For this control type, "count" might be a better name.
> Or at least say in the description that this is the number of bytes.

For the name of this variable, I don't mind using 'count'. But then, in 
next commit, snd_ctl_elem_add_bytes_set() has two arguments named 
'count'. And the consistency of API design is lost a bit.

I think that naming the variables depends on interpretation of 'struct 
snd_ctl_elem_value', therefore it mostly depends on taste of each 
developers. For example, to 'bytes' type element set, we can interpret 
'struct snd_ctl_elem_value.bytes' as either 'byte array in an element' 
or 'data for each channels with int8_t (=char) value for an element'.

So I propose the design of ALSA control core. If possible, I'd like to 
follow the design when adding new APIs for a consistent representation. 
If the proposed design is not propper, we can change the design for 
better shape. (but it will sometimes be a dull work depending on taste 
of each developers.)

And, I note that the name of 'channel' is picked up from Mixer APIs in 
alsa-lib. It doesn't come from my brain ;)


Thanks

Takashi Sakamoto