[alsa-devel] [PATCH 1/6] control: rename variables so that it represents the number of channels which an element has
Takashi Sakamoto
o-takashi at sakamocchi.jp
Tue Feb 23 09:52:21 CET 2016
On Feb 23 2016 09:48, Takashi Sakamoto wrote:
> An element has some channels which can be changed in a single operation
> from userspace. In control API, variables to represents the number of
> channels is described as 'count'. On the other hand, in ALSA control core,
> the number of elements in an element set is also described as 'count'.
> They're a bit confusing.
>
> This commit renames 'count' with 'channels'. The 'count' is reserved for
> future commit to describe the number of elements in an element set.
>
> Signed-off-by: Takashi Sakamoto <o-takashi at sakamocchi.jp>
> ---
> src/control/control.c | 38 ++++++++++++++++++++------------------
> 1 file changed, 20 insertions(+), 18 deletions(-)
>
> diff --git a/src/control/control.c b/src/control/control.c
> index 8a5d530..e02727a 100644
> --- a/src/control/control.c
> +++ b/src/control/control.c
> @@ -264,14 +264,15 @@ int snd_ctl_elem_info(snd_ctl_t *ctl, snd_ctl_elem_info_t *info)
> * \brief Create and add an user INTEGER CTL element
> * \param ctl CTL handle
> * \param id CTL element id to add
> - * \param count number of elements
> + * \param channels number of elements
Oops. This is incomplete because in my intension the description of this
argument represents the number of 'channels', not 'elements'.
> * \param min minimum value
> * \param max maximum value
> * \param step value step
> * \return 0 on success otherwise a negative error code
> */
> int snd_ctl_elem_add_integer(snd_ctl_t *ctl, const snd_ctl_elem_id_t *id,
> - unsigned int count, long min, long max, long step)
> + unsigned int channels, long min, long max,
> + long step)
> {
> snd_ctl_elem_info_t *info;
> snd_ctl_elem_value_t *val;
> @@ -284,7 +285,7 @@ int snd_ctl_elem_add_integer(snd_ctl_t *ctl, const snd_ctl_elem_id_t *id,
> info->type = SND_CTL_ELEM_TYPE_INTEGER;
> info->access = SNDRV_CTL_ELEM_ACCESS_READWRITE |
> SNDRV_CTL_ELEM_ACCESS_TLV_READWRITE;
> - info->count = count;
> + info->count = channels;
> info->value.integer.min = min;
> info->value.integer.max = max;
> info->value.integer.step = step;
> @@ -293,7 +294,7 @@ int snd_ctl_elem_add_integer(snd_ctl_t *ctl, const snd_ctl_elem_id_t *id,
> return err;
> snd_ctl_elem_value_alloca(&val);
> val->id = info->id;
> - for (i = 0; i < count; i++)
> + for (i = 0; i < channels; i++)
> val->value.integer.value[i] = min;
> err = ctl->ops->element_write(ctl, val);
> return err;
> @@ -303,15 +304,15 @@ int snd_ctl_elem_add_integer(snd_ctl_t *ctl, const snd_ctl_elem_id_t *id,
> * \brief Create and add an user INTEGER64 CTL element
> * \param ctl CTL handle
> * \param id CTL element id to add
> - * \param count number of elements
> + * \param channels number of elements
Ditto.
> * \param min minimum value
> * \param max maximum value
> * \param step value step
> * \return 0 on success otherwise a negative error code
> */
> int snd_ctl_elem_add_integer64(snd_ctl_t *ctl, const snd_ctl_elem_id_t *id,
> - unsigned int count, long long min, long long max,
> - long long step)
> + unsigned int channels, long long min,
> + long long max, long long step)
> {
> snd_ctl_elem_info_t *info;
> snd_ctl_elem_value_t *val;
> @@ -322,7 +323,7 @@ int snd_ctl_elem_add_integer64(snd_ctl_t *ctl, const snd_ctl_elem_id_t *id,
> snd_ctl_elem_info_alloca(&info);
> info->id = *id;
> info->type = SND_CTL_ELEM_TYPE_INTEGER64;
> - info->count = count;
> + info->count = channels;
> info->value.integer64.min = min;
> info->value.integer64.max = max;
> info->value.integer64.step = step;
> @@ -331,7 +332,7 @@ int snd_ctl_elem_add_integer64(snd_ctl_t *ctl, const snd_ctl_elem_id_t *id,
> return err;
> snd_ctl_elem_value_alloca(&val);
> val->id = info->id;
> - for (i = 0; i < count; i++)
> + for (i = 0; i < channels; i++)
> val->value.integer64.value[i] = min;
> err = ctl->ops->element_write(ctl, val);
> return err;
> @@ -341,11 +342,11 @@ int snd_ctl_elem_add_integer64(snd_ctl_t *ctl, const snd_ctl_elem_id_t *id,
> * \brief Create and add an user BOOLEAN CTL element
> * \param ctl CTL handle
> * \param id CTL element id to add
> - * \param count number of elements
> + * \param channels number of elements
Ditto.
> * \return 0 on success otherwise a negative error code
> */
> int snd_ctl_elem_add_boolean(snd_ctl_t *ctl, const snd_ctl_elem_id_t *id,
> - unsigned int count)
> + unsigned int channels)
> {
> snd_ctl_elem_info_t *info;
>
> @@ -353,7 +354,7 @@ int snd_ctl_elem_add_boolean(snd_ctl_t *ctl, const snd_ctl_elem_id_t *id,
> snd_ctl_elem_info_alloca(&info);
> info->id = *id;
> info->type = SND_CTL_ELEM_TYPE_BOOLEAN;
> - info->count = count;
> + info->count = channels;
> info->value.integer.min = 0;
> info->value.integer.max = 1;
> return ctl->ops->element_add(ctl, info);
> @@ -363,7 +364,7 @@ int snd_ctl_elem_add_boolean(snd_ctl_t *ctl, const snd_ctl_elem_id_t *id,
> * \brief Create and add a user-defined control element of type enumerated.
> * \param[in] ctl Control device handle.
> * \param[in] id ID of the new control element.
> - * \param[in] count Number of element values.
> + * \param[in] channels Number of element values.
Ditto.
> * \param[in] items Range of possible values (0 ... \a items - 1).
> * \param[in] names An array containing \a items strings.
> * \return Zero on success, otherwise a negative error code.
> @@ -380,9 +381,10 @@ int snd_ctl_elem_add_boolean(snd_ctl_t *ctl, const snd_ctl_elem_id_t *id,
> * \par Errors:
> * <dl>
> * <dt>-EBUSY<dd>A control element with ID \a id already exists.
> - * <dt>-EINVAL<dd>\a count is not at least one or greater than 128, or \a items
> - * is not at least one, or a string in \a names is empty or longer than 63
> - * bytes, or the strings in \a names require more than 64 KB storage.
> + * <dt>-EINVAL<dd>\a channels is not at least one or greater than 128, or \a
> + * items is not at least one, or a string in \a names is empty or longer
> + * than 63 bytes, or the strings in \a names require more than 64 KB
> + * storage.
> * <dt>-ENOMEM<dd>Out of memory, or there are too many user control elements.
> * <dt>-ENXIO<dd>This driver does not support (enumerated) user controls.
> * <dt>-ENODEV<dd>Device unplugged.
> @@ -392,7 +394,7 @@ int snd_ctl_elem_add_boolean(snd_ctl_t *ctl, const snd_ctl_elem_id_t *id,
> * snd_ctl_elem_add_enumerated() was introduced in ALSA 1.0.25.
> */
> int snd_ctl_elem_add_enumerated(snd_ctl_t *ctl, const snd_ctl_elem_id_t *id,
> - unsigned int count, unsigned int items,
> + unsigned int channels, unsigned int items,
> const char *const names[])
> {
> snd_ctl_elem_info_t *info;
> @@ -405,7 +407,7 @@ int snd_ctl_elem_add_enumerated(snd_ctl_t *ctl, const snd_ctl_elem_id_t *id,
> snd_ctl_elem_info_alloca(&info);
> info->id = *id;
> info->type = SND_CTL_ELEM_TYPE_ENUMERATED;
> - info->count = count;
> + info->count = channels;
> info->value.enumerated.items = items;
>
> bytes = 0;
Regards
Takashi Sakamoto
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