From bf1c9270875b722665d742f03b1859a038289b4b Mon Sep 17 00:00:00 2001
From: Wim Taymans <wtaymans@redhat.com>
Date: Wed, 5 Dec 2018 11:23:30 +0100
Subject: [PATCH] alsa: reset queued and free buffers on start

When we are out of buffers, drop the available samples.
---
 spa/plugins/alsa/alsa-utils.c | 23 ++++++++++++++++++++++-
 1 file changed, 22 insertions(+), 1 deletion(-)

diff --git a/spa/plugins/alsa/alsa-utils.c b/spa/plugins/alsa/alsa-utils.c
index dfa347cf8..9dc6112d8 100644
--- a/spa/plugins/alsa/alsa-utils.c
+++ b/spa/plugins/alsa/alsa-utils.c
@@ -769,7 +769,8 @@ push_frames(struct state *state,
 	snd_pcm_uframes_t total_frames = 0;
 
 	if (spa_list_is_empty(&state->free)) {
-		spa_log_trace(state->log, "no more buffers");
+		spa_log_warn(state->log, "no more buffers");
+		total_frames = state->threshold;
 	} else {
 		uint8_t *src;
 		size_t n_bytes;
@@ -940,6 +941,24 @@ next:
 	set_timeout(state, state->next_time);
 }
 
+static void reset_buffers(struct state *this)
+{
+	int i;
+
+	spa_list_init(&this->free);
+	spa_list_init(&this->ready);
+
+	for (i = 0; i < this->n_buffers; i++) {
+		struct buffer *b = &this->buffers[i];
+		if (this->stream == SND_PCM_STREAM_PLAYBACK) {
+			SPA_FLAG_SET(b->flags, BUFFER_FLAG_OUT);
+		} else {
+			spa_list_append(&this->free, &b->link);
+			SPA_FLAG_UNSET(b->flags, BUFFER_FLAG_OUT);
+		}
+	}
+}
+
 int spa_alsa_start(struct state *state)
 {
 	int err;
@@ -984,6 +1003,8 @@ int spa_alsa_start(struct state *state)
 		spa_loop_add_source(state->data_loop, &state->source);
 	}
 
+	reset_buffers(state);
+
 	if (state->stream == SND_PCM_STREAM_PLAYBACK) {
 		state->alsa_started = false;
 		spa_alsa_write(state, state->threshold * 2, true);