Enable Frontend callback for sharee.

Bug: 209873032
Test: cts.TunerTest#testShareFrontendFromTuner

Change-Id: Iffd4cb5070e65fb298006d9813ce1a5b5c069a5b
diff --git a/media/java/android/media/tv/tuner/Tuner.java b/media/java/android/media/tv/tuner/Tuner.java
index 94de7fa..255b391b 100644
--- a/media/java/android/media/tv/tuner/Tuner.java
+++ b/media/java/android/media/tv/tuner/Tuner.java
@@ -285,7 +285,7 @@
     @Nullable
     private FrontendInfo mFrontendInfo;
     private Integer mFrontendHandle;
-    private Boolean mIsSharedFrontend = false;
+    private Tuner mFeOwnerTuner = null;
     private int mFrontendType = FrontendSettings.TYPE_UNDEFINED;
     private int mUserId;
     private Lnb mLnb;
@@ -442,11 +442,10 @@
         mFrontendLock.lock();
         try {
             mTunerResourceManager.shareFrontend(mClientId, tuner.mClientId);
-            synchronized (mIsSharedFrontend) {
-                mFrontendHandle = tuner.mFrontendHandle;
-                mFrontend = tuner.mFrontend;
-                mIsSharedFrontend = true;
-            }
+            mFeOwnerTuner = tuner;
+            mFeOwnerTuner.registerFrontendCallbackListener(this);
+            mFrontendHandle = mFeOwnerTuner.mFrontendHandle;
+            mFrontend = mFeOwnerTuner.mFrontend;
             nativeShareFrontend(mFrontend.mId);
         } finally {
             releaseTRMSLock();
@@ -513,6 +512,27 @@
     private long mNativeContext; // used by native jMediaTuner
 
     /**
+     * Registers a tuner as a listener for frontend callbacks.
+     */
+    private void registerFrontendCallbackListener(Tuner tuner) {
+        nativeRegisterFeCbListener(tuner.getNativeContext());
+    }
+
+    /**
+     * Unregisters a tuner as a listener for frontend callbacks.
+     */
+    private void unregisterFrontendCallbackListener(Tuner tuner) {
+        nativeUnregisterFeCbListener(tuner.getNativeContext());
+    }
+
+    /**
+     * Returns the pointer to the associated JTuner.
+     */
+    long getNativeContext() {
+        return mNativeContext;
+    }
+
+    /**
      * Releases the Tuner instance.
      */
     @Override
@@ -526,19 +546,21 @@
         }
     }
 
-    private void releaseAll() {
+    private void releaseFrontend() {
         mFrontendLock.lock();
         try {
             if (mFrontendHandle != null) {
-                synchronized (mIsSharedFrontend) {
-                    if (!mIsSharedFrontend) {
-                        int res = nativeCloseFrontend(mFrontendHandle);
-                        if (res != Tuner.RESULT_SUCCESS) {
-                            TunerUtils.throwExceptionForResult(res, "failed to close frontend");
-                        }
-                        mTunerResourceManager.releaseFrontend(mFrontendHandle, mClientId);
+                if (mFeOwnerTuner != null) {
+                    // unregister self from the Frontend callback
+                    mFeOwnerTuner.unregisterFrontendCallbackListener(this);
+                    mFeOwnerTuner = null;
+                } else {
+                    // close resource as owner
+                    int res = nativeCloseFrontend(mFrontendHandle);
+                    if (res != Tuner.RESULT_SUCCESS) {
+                        TunerUtils.throwExceptionForResult(res, "failed to close frontend");
                     }
-                    mIsSharedFrontend = false;
+                    mTunerResourceManager.releaseFrontend(mFrontendHandle, mClientId);
                 }
                 FrameworkStatsLog
                         .write(FrameworkStatsLog.TV_TUNER_STATE_CHANGED, mUserId,
@@ -549,9 +571,14 @@
         } finally {
             mFrontendLock.unlock();
         }
+    }
+
+    private void releaseAll() {
+        releaseFrontend();
 
         mLnbLock.lock();
         try {
+            // mLnb will be non-null only for owner tuner
             if (mLnb != null) {
                 mLnb.close();
             }
@@ -641,6 +668,8 @@
      */
     private native Frontend nativeOpenFrontendByHandle(int handle);
     private native int nativeShareFrontend(int id);
+    private native void nativeRegisterFeCbListener(long nativeContext);
+    private native void nativeUnregisterFeCbListener(long nativeContext);
     @Result
     private native int nativeTune(int type, FrontendSettings settings);
     private native int nativeStopTune();
@@ -1276,7 +1305,7 @@
     }
 
     private void onFrontendEvent(int eventType) {
-        Log.d(TAG, "Got event from tuning. Event type: " + eventType);
+        Log.d(TAG, "Got event from tuning. Event type: " + eventType + " for " + this);
         synchronized (mOnTuneEventLock) {
             if (mOnTuneEventExecutor != null && mOnTuneEventListener != null) {
                 mOnTuneEventExecutor.execute(() -> {
diff --git a/media/jni/android_media_tv_Tuner.cpp b/media/jni/android_media_tv_Tuner.cpp
index c4dfee4..f19f6fd 100644
--- a/media/jni/android_media_tv_Tuner.cpp
+++ b/media/jni/android_media_tv_Tuner.cpp
@@ -947,20 +947,45 @@
 }
 
 /////////////// FrontendClientCallbackImpl ///////////////////////
-FrontendClientCallbackImpl::FrontendClientCallbackImpl(jweak tunerObj) : mObject(tunerObj) {}
+FrontendClientCallbackImpl::FrontendClientCallbackImpl(JTuner* jtuner, jweak listener) {
+    ALOGV("FrontendClientCallbackImpl() with listener:%p", listener);
+    addCallbackListener(jtuner, listener);
+}
+
+void FrontendClientCallbackImpl::addCallbackListener(JTuner* jtuner, jweak listener) {
+    JNIEnv *env = AndroidRuntime::getJNIEnv();
+    jweak listenerRef = env->NewWeakGlobalRef(listener);
+    ALOGV("addCallbackListener() with listener:%p and ref:%p @%p", listener, listenerRef, this);
+    std::scoped_lock<std::mutex> lock(mMutex);
+    mListenersMap[jtuner] = listenerRef;
+}
+
+void FrontendClientCallbackImpl::removeCallbackListener(JTuner* listener) {
+    ALOGV("removeCallbackListener for listener:%p", listener);
+    JNIEnv *env = AndroidRuntime::getJNIEnv();
+    std::scoped_lock<std::mutex> lock(mMutex);
+    if (mListenersMap.find(listener) != mListenersMap.end() && mListenersMap[listener]) {
+        env->DeleteWeakGlobalRef(mListenersMap[listener]);
+        mListenersMap.erase(listener);
+    }
+}
 
 void FrontendClientCallbackImpl::onEvent(FrontendEventType frontendEventType) {
     ALOGV("FrontendClientCallbackImpl::onEvent, type=%d", frontendEventType);
     JNIEnv *env = AndroidRuntime::getJNIEnv();
-    jobject frontend(env->NewLocalRef(mObject));
-    if (!env->IsSameObject(frontend, nullptr)) {
-        env->CallVoidMethod(
-                frontend,
-                gFields.onFrontendEventID,
-                (jint)frontendEventType);
-    } else {
-        ALOGE("FrontendClientCallbackImpl::onEvent:"
-                "Frontend object has been freed. Ignoring callback.");
+    std::scoped_lock<std::mutex> lock(mMutex);
+    for (const auto& mapEntry : mListenersMap) {
+        ALOGV("JTuner:%p, jweak:%p", mapEntry.first, mapEntry.second);
+        jobject frontend(env->NewLocalRef(mapEntry.second));
+        if (!env->IsSameObject(frontend, nullptr)) {
+            env->CallVoidMethod(
+                    frontend,
+                    gFields.onFrontendEventID,
+                    (jint)frontendEventType);
+        } else {
+            ALOGW("FrontendClientCallbackImpl::onEvent:"
+                    "Frontend object has been freed. Ignoring callback.");
+        }
     }
 }
 
@@ -969,12 +994,25 @@
     ALOGV("FrontendClientCallbackImpl::onScanMessage, type=%d", type);
     JNIEnv *env = AndroidRuntime::getJNIEnv();
     jclass clazz = env->FindClass("android/media/tv/tuner/Tuner");
-    jobject frontend(env->NewLocalRef(mObject));
-    if (env->IsSameObject(frontend, nullptr)) {
-        ALOGE("FrontendClientCallbackImpl::onScanMessage:"
-                "Frontend object has been freed. Ignoring callback.");
-        return;
+
+    std::scoped_lock<std::mutex> lock(mMutex);
+    for (const auto& mapEntry : mListenersMap) {
+        jobject frontend(env->NewLocalRef(mapEntry.second));
+        if (env->IsSameObject(frontend, nullptr)) {
+            ALOGE("FrontendClientCallbackImpl::onScanMessage:"
+                    "Tuner object has been freed. Ignoring callback.");
+            continue;
+        }
+        executeOnScanMessage(env, clazz, frontend, type, message);
     }
+}
+
+void FrontendClientCallbackImpl::executeOnScanMessage(
+         JNIEnv *env, const jclass& clazz, const jobject& frontend,
+         FrontendScanMessageType type,
+         const FrontendScanMessage& message) {
+    ALOGV("FrontendClientCallbackImpl::executeOnScanMessage, type=%d", type);
+
     switch(type) {
         case FrontendScanMessageType::LOCKED: {
             if (message.get<FrontendScanMessage::Tag::isLocked>()) {
@@ -1153,11 +1191,14 @@
 }
 
 FrontendClientCallbackImpl::~FrontendClientCallbackImpl() {
-    JNIEnv *env = AndroidRuntime::getJNIEnv();
-    if (mObject != nullptr) {
-        env->DeleteWeakGlobalRef(mObject);
-        mObject = nullptr;
+    JNIEnv *env = android::AndroidRuntime::getJNIEnv();
+    ALOGV("~FrontendClientCallbackImpl()");
+    std::scoped_lock<std::mutex> lock(mMutex);
+    for (const auto& mapEntry : mListenersMap) {
+        ALOGV("deleteRef :%p at @ %p", mapEntry.second, this);
+        env->DeleteWeakGlobalRef(mapEntry.second);
     }
+    mListenersMap.clear();
 }
 
 /////////////// Tuner ///////////////////////
@@ -1176,6 +1217,10 @@
     mSharedFeId = (int)Constant::INVALID_FRONTEND_ID;
 }
 
+jweak JTuner::getObject() {
+    return mObject;
+}
+
 JTuner::~JTuner() {
     if (mFeClient != nullptr) {
         mFeClient->close();
@@ -1188,6 +1233,7 @@
     env->DeleteWeakGlobalRef(mObject);
     env->DeleteGlobalRef(mClass);
     mFeClient = nullptr;
+    mFeClientCb = nullptr;
     mDemuxClient = nullptr;
     mClass = nullptr;
     mObject = nullptr;
@@ -1243,9 +1289,8 @@
         return nullptr;
     }
 
-    sp<FrontendClientCallbackImpl> feClientCb =
-            new FrontendClientCallbackImpl(env->NewWeakGlobalRef(mObject));
-    mFeClient->setCallback(feClientCb);
+    mFeClientCb = new FrontendClientCallbackImpl(this, mObject);
+    mFeClient->setCallback(mFeClientCb);
     // TODO: add more fields to frontend
     return env->NewObject(
             env->FindClass("android/media/tv/tuner/Tuner$Frontend"),
@@ -1265,6 +1310,18 @@
     return (int)Result::SUCCESS;
 }
 
+void JTuner::registerFeCbListener(JTuner* jtuner) {
+    if (mFeClientCb != nullptr && jtuner != nullptr) {
+        mFeClientCb->addCallbackListener(jtuner, jtuner->getObject());
+    }
+}
+
+void JTuner::unregisterFeCbListener(JTuner* jtuner) {
+    if (mFeClientCb != nullptr && jtuner != nullptr) {
+        mFeClientCb->removeCallbackListener(jtuner);
+    }
+}
+
 jobject JTuner::getAnalogFrontendCaps(JNIEnv *env, FrontendCapabilities &caps) {
     jclass clazz = env->FindClass("android/media/tv/tuner/frontend/AnalogFrontendCapabilities");
     jmethodID capsInit = env->GetMethodID(clazz, "<init>", "(II)V");
@@ -3184,6 +3241,20 @@
     return tuner->shareFrontend(id);
 }
 
+static void android_media_tv_Tuner_register_fe_cb_listener(
+        JNIEnv *env, jobject thiz, jlong shareeJTuner) {
+    sp<JTuner> tuner = getTuner(env, thiz);
+    JTuner *jtuner = (JTuner *)shareeJTuner;
+    tuner->registerFeCbListener(jtuner);
+}
+
+static void android_media_tv_Tuner_unregister_fe_cb_listener(
+        JNIEnv *env, jobject thiz, jlong shareeJTuner) {
+    sp<JTuner> tuner = getTuner(env, thiz);
+    JTuner *jtuner = (JTuner *)shareeJTuner;
+    tuner->unregisterFeCbListener(jtuner);
+}
+
 static int android_media_tv_Tuner_tune(JNIEnv *env, jobject thiz, jint type, jobject settings) {
     sp<JTuner> tuner = getTuner(env, thiz);
     FrontendSettings setting = getFrontendSettings(env, type, settings);
@@ -4346,6 +4417,10 @@
             (void *)android_media_tv_Tuner_open_frontend_by_handle },
     { "nativeShareFrontend", "(I)I",
             (void *)android_media_tv_Tuner_share_frontend },
+    { "nativeRegisterFeCbListener", "(J)V",
+            (void*)android_media_tv_Tuner_register_fe_cb_listener },
+    { "nativeUnregisterFeCbListener", "(J)V",
+            (void*)android_media_tv_Tuner_unregister_fe_cb_listener },
     { "nativeTune", "(ILandroid/media/tv/tuner/frontend/FrontendSettings;)I",
             (void *)android_media_tv_Tuner_tune },
     { "nativeStopTune", "()I", (void *)android_media_tv_Tuner_stop_tune },
diff --git a/media/jni/android_media_tv_Tuner.h b/media/jni/android_media_tv_Tuner.h
index 31d24ee..06e2492 100644
--- a/media/jni/android_media_tv_Tuner.h
+++ b/media/jni/android_media_tv_Tuner.h
@@ -149,14 +149,21 @@
     void getRestartEvent(jobjectArray& arr, const int size, const DemuxFilterEvent& event);
 };
 
+struct JTuner;
 struct FrontendClientCallbackImpl : public FrontendClientCallback {
-    FrontendClientCallbackImpl(jweak tunerObj);
+    FrontendClientCallbackImpl(JTuner*, jweak);
     ~FrontendClientCallbackImpl();
     virtual void onEvent(FrontendEventType frontendEventType);
     virtual void onScanMessage(
             FrontendScanMessageType type, const FrontendScanMessage& message);
 
-    jweak mObject;
+    void executeOnScanMessage(JNIEnv *env, const jclass& clazz, const jobject& frontend,
+                              FrontendScanMessageType type,
+                              const FrontendScanMessage& message);
+    void addCallbackListener(JTuner*, jweak obj);
+    void removeCallbackListener(JTuner* jtuner);
+    std::unordered_map<JTuner*, jweak> mListenersMap;
+    std::mutex mMutex;
 };
 
 struct JTuner : public RefBase {
@@ -171,6 +178,8 @@
     jobject getFrontendIds();
     jobject openFrontendByHandle(int feHandle);
     int shareFrontend(int feId);
+    void registerFeCbListener(JTuner* jtuner);
+    void unregisterFeCbListener(JTuner* jtuner);
     jint closeFrontendById(int id);
     jobject getFrontendInfo(int id);
     int tune(const FrontendSettings& settings);
@@ -192,6 +201,8 @@
     jint closeFrontend();
     jint closeDemux();
 
+    jweak getObject();
+
 protected:
     virtual ~JTuner();
 
@@ -200,6 +211,7 @@
     jweak mObject;
     static sp<TunerClient> mTunerClient;
     sp<FrontendClient> mFeClient;
+    sp<FrontendClientCallbackImpl> mFeClientCb;
     int mFeId;
     int mSharedFeId;
     sp<LnbClient> mLnbClient;