alsa: work around slightly broken _delay implementations

Use snd_pcm_avail_delay() in pa_alsa_safe_delay() so that we can check the delay
value against the avail value and patch it up when it looks invalid. Only do
this for capture.
This commit is contained in:
Wim Taymans 2010-09-08 13:26:39 +02:00 committed by Colin Guthrie
parent b0042cec71
commit f29acfd0e0
4 changed files with 46 additions and 6 deletions

View file

@ -1125,10 +1125,11 @@ snd_pcm_sframes_t pa_alsa_safe_avail(snd_pcm_t *pcm, size_t hwbuf_size, const pa
return n;
}
int pa_alsa_safe_delay(snd_pcm_t *pcm, snd_pcm_sframes_t *delay, size_t hwbuf_size, const pa_sample_spec *ss) {
int pa_alsa_safe_delay(snd_pcm_t *pcm, snd_pcm_sframes_t *delay, size_t hwbuf_size, const pa_sample_spec *ss, pa_bool_t capture) {
ssize_t k;
size_t abs_k;
int r;
snd_pcm_sframes_t avail = 0;
pa_assert(pcm);
pa_assert(delay);
@ -1136,9 +1137,10 @@ int pa_alsa_safe_delay(snd_pcm_t *pcm, snd_pcm_sframes_t *delay, size_t hwbuf_si
pa_assert(ss);
/* Some ALSA driver expose weird bugs, let's inform the user about
* what is going on */
* what is going on. We're going to get both the avail and delay values so
* that we can compare and check them for capture */
if ((r = snd_pcm_delay(pcm, delay)) < 0)
if ((r = snd_pcm_avail_delay(pcm, &avail, delay)) < 0)
return r;
k = (ssize_t) *delay * (ssize_t) pa_frame_size(ss);
@ -1167,6 +1169,44 @@ int pa_alsa_safe_delay(snd_pcm_t *pcm, snd_pcm_sframes_t *delay, size_t hwbuf_si
*delay = (snd_pcm_sframes_t) (hwbuf_size / pa_frame_size(ss));
}
if (capture) {
abs_k = (size_t) avail * pa_frame_size(ss);
if (abs_k >= hwbuf_size * 5 ||
abs_k >= pa_bytes_per_second(ss)*10) {
PA_ONCE_BEGIN {
char *dn = pa_alsa_get_driver_name_by_pcm(pcm);
pa_log(_("snd_pcm_avail() returned a value that is exceptionally large: %lu bytes (%lu ms).\n"
"Most likely this is a bug in the ALSA driver '%s'. Please report this issue to the ALSA developers."),
(unsigned long) k,
(unsigned long) (pa_bytes_to_usec(k, ss) / PA_USEC_PER_MSEC),
pa_strnull(dn));
pa_xfree(dn);
pa_alsa_dump(PA_LOG_ERROR, pcm);
} PA_ONCE_END;
/* Mhmm, let's try not to fail completely */
avail = (snd_pcm_sframes_t) (hwbuf_size / pa_frame_size(ss));
}
if (*delay < avail) {
PA_ONCE_BEGIN {
char *dn = pa_alsa_get_driver_name_by_pcm(pcm);
pa_log(_("snd_pcm_avail_delay() returned strange values: delay %lu is less than avail %lu.\n"
"Most likely this is a bug in the ALSA driver '%s'. Please report this issue to the ALSA developers."),
(unsigned long) *delay,
(unsigned long) avail,
pa_strnull(dn));
pa_xfree(dn);
pa_alsa_dump(PA_LOG_ERROR, pcm);
} PA_ONCE_END;
/* try to fixup */
*delay = avail;
}
}
return 0;
}