alsa: report xrun

When we record but there is not enough space in the ringbuffer, report
xrun.

1 files changed, 17 insertions, 1 deletions

diff --git a/pipewire-alsa/alsa-plugins/pcm_pipewire.c b/pipewire-alsa/alsa-plugins/pcm_pipewire.c
index 25626113..0e9944f7 100644
--- a/pipewire-alsa/alsa-plugins/pcm_pipewire.c
+++ b/pipewire-alsa/alsa-plugins/pcm_pipewire.c
@@ -64,6 +64,7 @@ typedef struct {
 	unsigned int activated:1;	/* PipeWire is activated? */
 	unsigned int drained:1;
 	unsigned int draining:1;
+	unsigned int xrun_detected:1;
 
 	snd_pcm_uframes_t hw_ptr;
 	snd_pcm_uframes_t boundary;
@@ -160,9 +161,15 @@ static int snd_pcm_pipewire_poll_revents(snd_pcm_ioplug_t *io,
 static snd_pcm_sframes_t snd_pcm_pipewire_pointer(snd_pcm_ioplug_t *io)
 {
 	snd_pcm_pipewire_t *pw = io->private_data;
+	if (pw->xrun_detected)
+		return -EPIPE;
 	if (pw->error < 0)
 		return pw->error;
+#ifdef SND_PCM_IOPLUG_FLAG_BOUNDARY_WA
 	return pw->hw_ptr;
+#else
+	return pw->hw_ptr % io->buffer_size;
+#endif
 }
 
 static int
@@ -274,13 +281,16 @@ snd_pcm_pipewire_process_record(snd_pcm_pipewire_t *pw, struct pw_buffer *b, snd
 	avail = SPA_MIN(maxsize, *hw_avail * bpf);
 	index = d[0].chunk->offset;
 
+	if (maxsize > *hw_avail)
+		pw->xrun_detected = true;
+
 	do {
 	avail = SPA_MIN(avail, pw->min_avail * bpf);
 	offset = index % maxsize;
 	nbytes = SPA_MIN(avail, maxsize - offset);
 	ptr = SPA_MEMBER(d[0].data, offset, void);
 
-	pw_log_trace(NAME" %p: %d %d %d %p", pw, nbytes, avail, offset, ptr);
+	pw_log_trace(NAME" %p: %d %ld %d %d %d %p", pw, maxsize, *hw_avail, nbytes, avail, offset, ptr);
 	nframes = nbytes / bpf;
 
 	for (channel = 0; channel < io->channels; channel++) {
@@ -481,6 +491,7 @@ static int snd_pcm_pipewire_prepare(snd_pcm_ioplug_t *io)
 
 done:
 	pw->hw_ptr = 0;
+	pw->xrun_detected = false;
 
 	pw_thread_loop_unlock(pw->main_loop);
 
@@ -951,6 +962,11 @@ static int snd_pcm_pipewire_open(snd_pcm_t **pcmp, const char *name,
 	pw->io.poll_fd = pw->fd;
 	pw->io.poll_events = POLLIN;
 	pw->io.mmap_rw = 1;
+#ifdef SND_PCM_IOPLUG_FLAG_BOUNDARY_WA
+	pw->io.flags = SND_PCM_IOPLUG_FLAG_BOUNDARY_WA;
+#else
+#warning hw_ptr updates of buffer_size will not be recognized by the ALSA library. Consider to update your ALSA library.
+#endif
 
 	if ((err = snd_pcm_ioplug_create(&pw->io, name, stream, mode)) < 0)
 		goto error;