fixed #17800: [iOS] Streaming audio (normally a background music) maybe cut and may not be looped. (#17947)

* fixed #17800: [iOS] Streaming audio (normally a background music) may be cut and may not be looped.

* Updates including.

cocos/audio/apple/AudioEngine-inl.h

@@ -66,6 +66,7 @@ public:
 
 private:
     void _play2d(AudioCache *cache, int audioID);
+    static ALvoid myAlSourceNotificationCallback(ALuint sid, ALuint notificationID, ALvoid* userData);
 
     ALuint _alSources[MAX_AUDIOINSTANCES];
 

cocos/audio/apple/AudioEngine-inl.mm

@@ -41,8 +41,27 @@
 using namespace cocos2d;
 using namespace cocos2d::experimental;
 
-static ALCdevice *s_ALDevice = nullptr;
-static ALCcontext *s_ALContext = nullptr;
+static ALCdevice* s_ALDevice = nullptr;
+static ALCcontext* s_ALContext = nullptr;
+static AudioEngineImpl* s_instance = nullptr;
+
+typedef ALvoid (*alSourceNotificationProc)(ALuint sid, ALuint notificationID, ALvoid* userData);
+typedef ALenum (*alSourceAddNotificationProcPtr)(ALuint sid, ALuint notificationID, alSourceNotificationProc notifyProc, ALvoid* userData);
+static ALenum alSourceAddNotificationExt(ALuint sid, ALuint notificationID, alSourceNotificationProc notifyProc, ALvoid* userData)
+{
+    static alSourceAddNotificationProcPtr proc = nullptr;
+
+    if (proc == nullptr)
+    {
+        proc = (alSourceAddNotificationProcPtr)alcGetProcAddress(nullptr, "alSourceAddNotification");
+    }
+
+    if (proc)
+    {
+        return proc(sid, notificationID, notifyProc, userData);
+    }
+    return AL_INVALID_VALUE;
+}
 
 #if CC_TARGET_PLATFORM == CC_PLATFORM_IOS
 @interface AudioEngineSessionHandler : NSObject
@@ -189,12 +208,29 @@ void AudioEngineInterruptionListenerCallback(void* user_data, UInt32 interruptio
 static id s_AudioEngineSessionHandler = nullptr;
 #endif
 
+ALvoid AudioEngineImpl::myAlSourceNotificationCallback(ALuint sid, ALuint notificationID, ALvoid* userData)
+{
+    // Currently, we only care about AL_BUFFERS_PROCESSED event
+    if (notificationID != AL_BUFFERS_PROCESSED)
+        return;
+
+    AudioPlayer* player = nullptr;
+    for (const auto& e : s_instance->_audioPlayers)
+    {
+        player = e.second;
+        if (player->_alSource == sid && player->_streamingSource)
+        {
+            player->wakeupRotateThread();
+        }
+    }
+}
+
 AudioEngineImpl::AudioEngineImpl()
 : _lazyInitLoop(true)
 , _currentAudioID(0)
 , _scheduler(nullptr)
 {
-
+    s_instance = this;
 }
 
 AudioEngineImpl::~AudioEngineImpl()
@@ -219,6 +255,7 @@ AudioEngineImpl::~AudioEngineImpl()
 #if CC_TARGET_PLATFORM == CC_PLATFORM_IOS
     [s_AudioEngineSessionHandler release];
 #endif
+    s_instance = nullptr;
 }
 
 bool AudioEngineImpl::init()
@@ -245,6 +282,7 @@ bool AudioEngineImpl::init()
 
             for (int i = 0; i < MAX_AUDIOINSTANCES; ++i) {
                 _alSourceUsed[_alSources[i]] = false;
+                alSourceAddNotificationExt(_alSources[i], AL_BUFFERS_PROCESSED, myAlSourceNotificationCallback, nullptr);
             }
 
             // fixed #16170: Random crash in alGenBuffers(AudioCache::readDataTask) at startup
@@ -308,7 +346,6 @@ bool AudioEngineImpl::init()
 
             // ================ Workaround end ================ //
 
-
             _scheduler = Director::getInstance()->getScheduler();
             ret = true;
             ALOGI("OpenAL was initialized successfully!");

cocos/audio/apple/AudioPlayer.h

@@ -27,12 +27,14 @@
 #include "platform/CCPlatformConfig.h"
 #if CC_TARGET_PLATFORM == CC_PLATFORM_IOS || CC_TARGET_PLATFORM == CC_PLATFORM_MAC
 
+#include "platform/CCPlatformMacros.h"
+#include "audio/apple/AudioMacros.h"
+
 #include <condition_variable>
 #include <mutex>
 #include <string>
 #include <thread>
-#import <OpenAL/al.h>
-#include "platform/CCPlatformMacros.h"
+#include <OpenAL/al.h>
 
 NS_CC_BEGIN
 namespace experimental{
@@ -57,6 +59,7 @@ protected:
     void setCache(AudioCache* cache);
     void rotateBufferThread(int offsetFrame);
     bool play2d();
+    void wakeupRotateThread();
 
     AudioCache* _audioCache;
 
@@ -72,12 +75,13 @@ protected:
     //play by circular buffer
     float _currTime;
     bool _streamingSource;
-    ALuint _bufferIds[3];
+    ALuint _bufferIds[QUEUEBUFFER_NUM];
     std::thread* _rotateBufferThread;
     std::condition_variable _sleepCondition;
     std::mutex _sleepMutex;
     bool _timeDirty;
     bool _isRotateThreadExited;
+    std::atomic_bool _needWakeupRotateThread;
 
     std::mutex _play2dMutex;
 

cocos/audio/apple/AudioPlayer.mm

@@ -59,6 +59,7 @@ AudioPlayer::AudioPlayer()
 , _rotateBufferThread(nullptr)
 , _timeDirty(false)
 , _isRotateThreadExited(false)
+, _needWakeupRotateThread(false)
 , _id(++__idIndex)
 {
     memset(_bufferIds, 0, sizeof(_bufferIds));
@@ -71,7 +72,7 @@ AudioPlayer::~AudioPlayer()
 
     if (_streamingSource)
     {
-        alDeleteBuffers(3, _bufferIds);
+        alDeleteBuffers(QUEUEBUFFER_NUM, _bufferIds);
     }
 }
 
@@ -172,7 +173,7 @@ bool AudioPlayer::play2d()
         }
         else
         {
-            alGenBuffers(3, _bufferIds);
+            alGenBuffers(QUEUEBUFFER_NUM, _bufferIds);
 
             auto alError = alGetError();
             if (alError == AL_NO_ERROR)
@@ -302,7 +303,12 @@ void AudioPlayer::rotateBufferThread(int offsetFrame)
                 break;
             }
 
-            _sleepCondition.wait_for(lk,std::chrono::milliseconds(75));
+            if (!_needWakeupRotateThread)
+            {
+                _sleepCondition.wait_for(lk,std::chrono::milliseconds(75));
+            }
+
+            _needWakeupRotateThread = false;
         }
 
     } while(false);
@@ -313,6 +319,12 @@ void AudioPlayer::rotateBufferThread(int offsetFrame)
     _isRotateThreadExited = true;
 }
 
+void AudioPlayer::wakeupRotateThread()
+{
+    _needWakeupRotateThread = true;
+    _sleepCondition.notify_all();
+}
+
 bool AudioPlayer::setLoop(bool loop)
 {
     if (!_isDestroyed ) {