Workaround for getting AL_STOPPTED state after alSourcePlay(sourceId). (#18228)

cocos/audio/apple/AudioEngine-inl.h

@@ -66,12 +66,14 @@ public:
 
 private:
     void _play2d(AudioCache *cache, int audioID);
+    ALuint findValidSource();
+
     static ALvoid myAlSourceNotificationCallback(ALuint sid, ALuint notificationID, ALvoid* userData);
 
     ALuint _alSources[MAX_AUDIOINSTANCES];
 
     //source,used
-    std::unordered_map<ALuint, bool> _alSourceUsed;
+    std::list<ALuint> _unusedSourcesPool;
 
     //filePath,bufferInfo
     std::unordered_map<std::string, AudioCache> _audioCaches;

cocos/audio/apple/AudioEngine-inl.mm

@@ -289,7 +289,7 @@ bool AudioEngineImpl::init()
             }
 
             for (int i = 0; i < MAX_AUDIOINSTANCES; ++i) {
-                _alSourceUsed[_alSources[i]] = false;
+                _unusedSourcesPool.push_back(_alSources[i]);
                 alSourceAddNotificationExt(_alSources[i], AL_BUFFERS_PROCESSED, myAlSourceNotificationCallback, nullptr);
             }
 
@@ -400,17 +400,9 @@ int AudioEngineImpl::play2d(const std::string &filePath ,bool loop ,float volume
         return AudioEngine::INVALID_AUDIO_ID;
     }
 
-    bool sourceFlag = false;
-    ALuint alSource = 0;
-    for (int i = 0; i < MAX_AUDIOINSTANCES; ++i) {
-        alSource = _alSources[i];
-
-        if ( !_alSourceUsed[alSource]) {
-            sourceFlag = true;
-            break;
-        }
-    }
-    if(!sourceFlag){
+    ALuint alSource = findValidSource();
+    if (alSource == AL_INVALID)
+    {
         return AudioEngine::INVALID_AUDIO_ID;
     }
 
@@ -434,8 +426,6 @@ int AudioEngineImpl::play2d(const std::string &filePath ,bool loop ,float volume
     _audioPlayers[_currentAudioID] = player;
     _threadMutex.unlock();
 
-    _alSourceUsed[alSource] = true;
-
     audioCache->addPlayCallback(std::bind(&AudioEngineImpl::_play2d,this,audioCache,_currentAudioID));
 
     if (_lazyInitLoop) {
@@ -474,6 +464,18 @@ void AudioEngineImpl::_play2d(AudioCache *cache, int audioID)
     }
 }
 
+ALuint AudioEngineImpl::findValidSource()
+{
+    ALuint sourceId = AL_INVALID;
+    if (!_unusedSourcesPool.empty())
+    {
+        sourceId = _unusedSourcesPool.front();
+        _unusedSourcesPool.pop_front();
+    }
+
+    return sourceId;
+}
+
 void AudioEngineImpl::setVolume(int audioID,float volume)
 {
     auto player = _audioPlayers[audioID];
@@ -546,9 +548,6 @@ void AudioEngineImpl::stop(int audioID)
 {
     auto player = _audioPlayers[audioID];
     player->destroy();
-    //Note: Don't set the flag to false here, it should be set in 'update' function.
-    // Otherwise, the state got from alSourceState may be wrong
-//    _alSourceUsed[player->_alSource] = false;
 
     // Call 'update' method to cleanup immediately since the schedule may be cancelled without any notification.
     update(0.0f);
@@ -560,12 +559,6 @@ void AudioEngineImpl::stopAll()
     {
         player.second->destroy();
     }
-    //Note: Don't set the flag to false here, it should be set in 'update' function.
-    // Otherwise, the state got from alSourceState may be wrong
-//    for(int index = 0; index < MAX_AUDIOINSTANCES; ++index)
-//    {
-//        _alSourceUsed[_alSources[index]] = false;
-//    }
 
     // Call 'update' method to cleanup immediately since the schedule may be cancelled without any notification.
     update(0.0f);
@@ -662,7 +655,7 @@ void AudioEngineImpl::update(float dt)
             it = _audioPlayers.erase(it);
             _threadMutex.unlock();
             delete player;
-            _alSourceUsed[alSource] = false;
+            _unusedSourcesPool.push_back(alSource);
         }
         else if (player->_ready && sourceState == AL_STOPPED) {
 
@@ -682,7 +675,7 @@ void AudioEngineImpl::update(float dt)
             }
 
             delete player;
-            _alSourceUsed[alSource] = false;
+            _unusedSourcesPool.push_back(alSource);
         }
         else{
             ++it;