pcm_utils: check pcm_convert()==0

It is illegal to pass an empty audio buffer around.  pcm_resample()
sometimes seems to result in 0 samples, maybe related to
libsamplerate.  To work around that problem, add special checks after
both pcm_convert() invocations.  Removed the pcm_resample()==0 checks
from pcm_convert().

1 files changed, 9 insertions, 1 deletions

diff --git a/src/output_thread.c b/src/output_thread.c
index b65a601a3..c887828bb 100644
--- a/src/output_thread.c
+++ b/src/output_thread.c
@@ -69,9 +69,17 @@ static void ao_play(struct audio_output *ao)
 
 	assert(size > 0);
 
-	if (!audio_format_equals(&ao->inAudioFormat, &ao->outAudioFormat))
+	if (!audio_format_equals(&ao->inAudioFormat, &ao->outAudioFormat)) {
 		convertAudioFormat(ao, &data, &size);
 
+		/* under certain circumstances, pcm_convert() may
+		   return an empty buffer - this condition should be
+		   investigated further, but for now, do this check as
+		   a workaround: */
+		if (size == 0)
+			return;
+	}
+
 	ret = ao->plugin->play(ao->data, data, size);
 	if (!ret) {
 		ao->plugin->cancel(ao->data);