At Sun, 31 Aug 2014 22:23:47 +0600, Alexander E. Patrakov wrote:

This function returned incorrect results when hw.ptr was near the boundary and hw.appl_ptr was near zero. Here "incorrect" means "greater than the boundary".

The result was incorrect, because it was used as a return value of various *_rewindable() functions and also as the delay for ioplug.

Signed-off-by: Alexander E. Patrakov patrakov@gmail.com

Hrm, the very early version of snd_pcm_mmap_hw_avail() was correctly implemented:

static inline ssize_t snd_pcm_mmap_hw_avail(snd_pcm_t *pcm) { if (pcm->stream == SND_PCM_STREAM_PLAYBACK) return snd_pcm_mmap_playback_hw_avail(pcm); else return snd_pcm_mmap_capture_hw_avail(pcm); }

Since the commit 9a435c2d934a, the breakage was introduced there. I have no idea what and why this was done so, it's a really old commit more than a decade ago.

In anyway, your fix look good and simple, so I applied it as is now, instead of reverting to the old version above.

BTW, at the next done, don't forget to put maintainers to Cc.

thanks,

Takashi

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src/pcm/pcm_local.h | 8 +------- 1 file changed, 1 insertion(+), 7 deletions(-)

diff --git a/src/pcm/pcm_local.h b/src/pcm/pcm_local.h index 80bbe59..74ebd60 100644 --- a/src/pcm/pcm_local.h +++ b/src/pcm/pcm_local.h @@ -461,13 +461,7 @@ static inline snd_pcm_sframes_t snd_pcm_mmap_capture_hw_avail(snd_pcm_t *pcm)

static inline snd_pcm_sframes_t snd_pcm_mmap_hw_avail(snd_pcm_t *pcm) {

• snd_pcm_sframes_t avail;
• avail = *pcm->hw.ptr - *pcm->appl.ptr;
• if (pcm->stream == SND_PCM_STREAM_PLAYBACK)

• avail += pcm->buffer_size;
  

• if (avail < 0)

• avail += pcm->boundary;
  

• return pcm->buffer_size - avail;

• return pcm->buffer_size - snd_pcm_mmap_avail(pcm);

}

static inline const snd_pcm_channel_area_t *snd_pcm_mmap_areas(snd_pcm_t *pcm)

2.1.0

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