From 5980b0b9abb77c7a2a5b4709de0255fb6db03a48 Mon Sep 17 00:00:00 2001
From: rdb <git@rdb.name>
Date: Fri, 5 Jan 2018 13:37:00 +0100
Subject: [PATCH] openal: fix warning spam every frame in newer AL
 implementations

This fixes error messages being generated of the form:
AL lib: (WW) alSetError: Error generated on context 0x801cf8800, code 0xa003

This is caused by alSourceUnqueueBuffers being called without first checking whether processed buffers are available using alGetSourcei.

Fixes #180
---
 panda/src/audiotraits/openalAudioSound.cxx | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/panda/src/audiotraits/openalAudioSound.cxx b/panda/src/audiotraits/openalAudioSound.cxx
index da379bfd5c..9abaf24036 100644
--- a/panda/src/audiotraits/openalAudioSound.cxx
+++ b/panda/src/audiotraits/openalAudioSound.cxx
@@ -435,7 +435,11 @@ pull_used_buffers() {
   ReMutexHolder holder(OpenALAudioManager::_lock);
   while (_stream_queued.size()) {
     ALuint buffer = 0;
-    alGetError();
+    ALint num_buffers = 0;
+    alGetSourcei(_source, AL_BUFFERS_PROCESSED, &num_buffers);
+    if (num_buffers <= 0) {
+      break;
+    }
     alSourceUnqueueBuffers(_source, 1, &buffer);
     int err = alGetError();
     if (err == AL_NO_ERROR) {