[PATCH alsa-lib 1/4] pcm: direct: Fix the missing appl_ptr update

Takashi Iwai tiwai at suse.de
Fri Jan 22 15:48:39 CET 2021


A snd_pcm_status() call for the direct plugins receives the status
from the slave PCM, but this doesn't contain a valid appl_ptr, since
the slave PCM for the direct plugins is in a free-wheel mode, hence
the appl_ptr is always zero.  This result in the inconsistent
status->appl_ptr and pcm->appl.ptr, hitting the recently introduced
assert() call.

Fix it by transferring the plugin's appl_ptr to the upper caller.

BugLink: https://bugzilla.opensuse.org/show_bug.cgi?id=1181194
Signed-off-by: Takashi Iwai <tiwai at suse.de>
---
 src/pcm/pcm_dmix.c   | 1 +
 src/pcm/pcm_dshare.c | 1 +
 src/pcm/pcm_dsnoop.c | 1 +
 3 files changed, 3 insertions(+)

diff --git a/src/pcm/pcm_dmix.c b/src/pcm/pcm_dmix.c
index be2675aff0f3..d8495065d5d7 100644
--- a/src/pcm/pcm_dmix.c
+++ b/src/pcm/pcm_dmix.c
@@ -495,6 +495,7 @@ static int snd_pcm_dmix_status(snd_pcm_t *pcm, snd_pcm_status_t * status)
 	}
 
 	status->state = snd_pcm_dmix_state(pcm);
+	status->appl_ptr = *pcm->appl.ptr; /* slave PCM doesn't set appl_ptr */
 	status->trigger_tstamp = dmix->trigger_tstamp;
 	status->avail = snd_pcm_mmap_playback_avail(pcm);
 	status->avail_max = status->avail > dmix->avail_max ? status->avail : dmix->avail_max;
diff --git a/src/pcm/pcm_dshare.c b/src/pcm/pcm_dshare.c
index 10243013714d..dccb137be253 100644
--- a/src/pcm/pcm_dshare.c
+++ b/src/pcm/pcm_dshare.c
@@ -243,6 +243,7 @@ static int snd_pcm_dshare_status(snd_pcm_t *pcm, snd_pcm_status_t * status)
 		break;
 	}
 	status->state = snd_pcm_dshare_state(pcm);
+	status->appl_ptr = *pcm->appl.ptr; /* slave PCM doesn't set appl_ptr */
 	status->trigger_tstamp = dshare->trigger_tstamp;
 	status->avail = snd_pcm_mmap_playback_avail(pcm);
 	status->avail_max = status->avail > dshare->avail_max ? status->avail : dshare->avail_max;
diff --git a/src/pcm/pcm_dsnoop.c b/src/pcm/pcm_dsnoop.c
index c6e8cd279b53..695bf4aa340e 100644
--- a/src/pcm/pcm_dsnoop.c
+++ b/src/pcm/pcm_dsnoop.c
@@ -193,6 +193,7 @@ static int snd_pcm_dsnoop_status(snd_pcm_t *pcm, snd_pcm_status_t * status)
 	snd_pcm_status(dsnoop->spcm, status);
 	state = snd_pcm_state(dsnoop->spcm);
 	status->state = state == SND_PCM_STATE_RUNNING ? dsnoop->state : state;
+	status->appl_ptr = *pcm->appl.ptr; /* slave PCM doesn't set appl_ptr */
 	status->trigger_tstamp = dsnoop->trigger_tstamp;
 	status->avail = snd_pcm_mmap_capture_avail(pcm);
 	status->avail_max = status->avail > dsnoop->avail_max ? status->avail : dsnoop->avail_max;
-- 
2.26.2



More information about the Alsa-devel mailing list