From: Timo Wischer twischer@de.adit-jv.com
This function can be called without calling snd_pcm_avail_update().
The call to snd_pcm_avail_update() can take some time. Therefore some developers would not like to call it from a real-time context (e.g. from JACK client context).
Signed-off-by: Timo Wischer twischer@de.adit-jv.com
diff --git a/include/pcm_ioplug.h b/include/pcm_ioplug.h index c1310e3..b16fc8b 100644 --- a/include/pcm_ioplug.h +++ b/include/pcm_ioplug.h @@ -235,6 +235,9 @@ int snd_pcm_ioplug_set_param_list(snd_pcm_ioplug_t *io, int type, unsigned int n int snd_pcm_ioplug_set_state(snd_pcm_ioplug_t *ioplug, snd_pcm_state_t state);
/* calucalte the available frames */ +snd_pcm_uframes_t snd_pcm_ioplug_avail(const snd_pcm_ioplug_t * const ioplug, + const snd_pcm_uframes_t hw_ptr, + const snd_pcm_uframes_t appl_ptr); snd_pcm_uframes_t snd_pcm_ioplug_hw_avail(const snd_pcm_ioplug_t * const ioplug, const snd_pcm_uframes_t hw_ptr, const snd_pcm_uframes_t appl_ptr); diff --git a/src/pcm/pcm_ioplug.c b/src/pcm/pcm_ioplug.c index 4d44ae2..6d52c27 100644 --- a/src/pcm/pcm_ioplug.c +++ b/src/pcm/pcm_ioplug.c @@ -1221,6 +1221,21 @@ int snd_pcm_ioplug_set_state(snd_pcm_ioplug_t *ioplug, snd_pcm_state_t state) * \param ioplug the ioplug handle * \param hw_ptr hardware pointer in frames * \param appl_ptr application pointer in frames + * \return available frames for the application + */ +snd_pcm_uframes_t snd_pcm_ioplug_avail(const snd_pcm_ioplug_t * const ioplug, + const snd_pcm_uframes_t hw_ptr, + const snd_pcm_uframes_t appl_ptr) +{ + return __snd_pcm_avail(ioplug->pcm, hw_ptr, appl_ptr); +} + +/** + * \brief Get the available frames. This function can be used to calculate the + * the available frames before calling #snd_pcm_avail_update() + * \param ioplug the ioplug handle + * \param hw_ptr hardware pointer in frames + * \param appl_ptr application pointer in frames * \return available frames for the hardware */ snd_pcm_uframes_t snd_pcm_ioplug_hw_avail(const snd_pcm_ioplug_t * const ioplug, @@ -1230,8 +1245,9 @@ snd_pcm_uframes_t snd_pcm_ioplug_hw_avail(const snd_pcm_ioplug_t * const ioplug, /* available data/space which can be transferred by the user * application */ - const snd_pcm_uframes_t user_avail = __snd_pcm_avail(ioplug->pcm, - hw_ptr, appl_ptr); + const snd_pcm_uframes_t user_avail = snd_pcm_ioplug_avail(ioplug, + hw_ptr, + appl_ptr);
if (user_avail > ioplug->pcm->buffer_size) { /* there was an Xrun */