[alsa-devel] [PATCH 1/1] Alsa: seq: correctly detect input buffer overflow

[Takashi Iwai]

At Wed,  4 Jun 2014 01:02:51 -0400,
Adam Goode wrote:
> 
> snd_seq_event_dup returns -ENOMEM in some buffer-full conditions,
> but usually returns -EAGAIN. Make -EAGAIN trigger the overflow
> condition in snd_seq_fifo_event_in so that the fifo is cleared
> and -ENOSPC is returned to userspace as stated in the alsa-lib docs.
> 
> Signed-off-by: Adam Goode <agoode at google.com>

Thanks, applied.


Takashi

> 
> diff --git a/sound/core/seq/seq_fifo.c b/sound/core/seq/seq_fifo.c
> index 5599899..53a403e 100644
> --- a/sound/core/seq/seq_fifo.c
> +++ b/sound/core/seq/seq_fifo.c
> @@ -124,7 +124,7 @@ int snd_seq_fifo_event_in(struct snd_seq_fifo *f,
>  	snd_use_lock_use(&f->use_lock);
>  	err = snd_seq_event_dup(f->pool, event, &cell, 1, NULL); /* always non-blocking */
>  	if (err < 0) {
> -		if (err == -ENOMEM)
> +		if ((err == -ENOMEM) || (err == -EAGAIN))
>  			atomic_inc(&f->overflow);
>  		snd_use_lock_free(&f->use_lock);
>  		return err;
> -- 
> 1.9.1.423.g4596e3a
>