Revert^2 "Migrate audio permission provider prop listener"

This reverts commit 236f2a163e657ec4db7eda810db45cac16897ffa.

Reason for revert: Reapply

Change-Id: Ia3cec6493e1d0d54b44175bf8f183c4c937b6449

9 files changed, 124 insertions, 31 deletions

diff --git a/core/jni/android_media_AudioSystem.cpp b/core/jni/android_media_AudioSystem.cpp
index eaff7608ce3b..a278fea3b9bc 100644
--- a/core/jni/android_media_AudioSystem.cpp
+++ b/core/jni/android_media_AudioSystem.cpp
@@ -27,6 +27,7 @@
 #include <android_media_audiopolicy.h>
 #include <android_os_Parcel.h>
 #include <audiomanager/AudioManager.h>
+#include <android-base/properties.h>
 #include <binder/IBinder.h>
 #include <jni.h>
 #include <media/AidlConversion.h>
@@ -41,8 +42,10 @@
 #include <system/audio_policy.h>
 #include <utils/Log.h>
 
+#include <thread>
 #include <optional>
 #include <sstream>
+#include <memory>
 #include <vector>
 
 #include "android_media_AudioAttributes.h"
@@ -261,6 +264,13 @@ static struct {
     jfieldID mMixerBehavior;
 } gAudioMixerAttributesField;
 
+static struct {
+    jclass clazz;
+    jmethodID run;
+} gRunnableClassInfo;
+
+static JavaVM* gVm;
+
 static Mutex gLock;
 
 enum AudioError {
@@ -3363,6 +3373,55 @@ static jboolean android_media_AudioSystem_isBluetoothVariableLatencyEnabled(JNIE
     return enabled;
 }
 
+class JavaSystemPropertyListener {
+  public:
+    JavaSystemPropertyListener(JNIEnv* env, jobject javaCallback, std::string sysPropName) :
+            mCallback(env->NewGlobalRef(javaCallback)),
+            mCachedProperty(android::base::CachedProperty{std::move(sysPropName)}) {
+        mListenerThread = std::thread([this]() mutable {
+            JNIEnv* threadEnv = GetOrAttachJNIEnvironment(gVm);
+            while (!mCleanupSignal.load()) {
+                using namespace std::chrono_literals;
+                // 1s timeout so this thread can read the cleanup signal to (slowly) be able to
+                // be destroyed.
+                std::string newVal = mCachedProperty.WaitForChange(1000ms) ?: "";
+                if (newVal != "" && mLastVal != newVal) {
+                    threadEnv->CallVoidMethod(mCallback, gRunnableClassInfo.run);
+                    mLastVal = std::move(newVal);
+                }
+            }
+            });
+    }
+
+    ~JavaSystemPropertyListener() {
+        mCleanupSignal.store(true);
+        mListenerThread.join();
+        JNIEnv* env = GetOrAttachJNIEnvironment(gVm);
+        env->DeleteGlobalRef(mCallback);
+    }
+
+  private:
+    jobject mCallback;
+    android::base::CachedProperty mCachedProperty;
+    std::thread mListenerThread;
+    std::atomic<bool> mCleanupSignal{false};
+    std::string mLastVal = "";
+};
+
+std::vector<std::unique_ptr<JavaSystemPropertyListener>> gSystemPropertyListeners;
+std::mutex gSysPropLock{};
+
+static void android_media_AudioSystem_listenForSystemPropertyChange(JNIEnv *env,  jobject thiz,
+        jstring sysProp,
+        jobject javaCallback) {
+    ScopedUtfChars sysPropChars{env, sysProp};
+    auto listener = std::make_unique<JavaSystemPropertyListener>(env, javaCallback,
+            std::string{sysPropChars.c_str()});
+    std::unique_lock _l{gSysPropLock};
+    gSystemPropertyListeners.push_back(std::move(listener));
+}
+
+
 // ----------------------------------------------------------------------------
 
 #define MAKE_AUDIO_SYSTEM_METHOD(x) \
@@ -3535,7 +3594,12 @@ static const JNINativeMethod gMethods[] =
                                 android_media_AudioSystem_clearPreferredMixerAttributes),
          MAKE_AUDIO_SYSTEM_METHOD(supportsBluetoothVariableLatency),
          MAKE_AUDIO_SYSTEM_METHOD(setBluetoothVariableLatencyEnabled),
-         MAKE_AUDIO_SYSTEM_METHOD(isBluetoothVariableLatencyEnabled)};
+         MAKE_AUDIO_SYSTEM_METHOD(isBluetoothVariableLatencyEnabled),
+         MAKE_JNI_NATIVE_METHOD("listenForSystemPropertyChange",
+                                "(Ljava/lang/String;Ljava/lang/Runnable;)V",
+                                android_media_AudioSystem_listenForSystemPropertyChange),
+
+        };
 
 static const JNINativeMethod gEventHandlerMethods[] =
         {MAKE_JNI_NATIVE_METHOD("native_setup", "(Ljava/lang/Object;)V",
@@ -3817,6 +3881,12 @@ int register_android_media_AudioSystem(JNIEnv *env)
     gAudioMixerAttributesField.mMixerBehavior =
             GetFieldIDOrDie(env, audioMixerAttributesClass, "mMixerBehavior", "I");
 
+    jclass runnableClazz = FindClassOrDie(env, "java/lang/Runnable");
+    gRunnableClassInfo.clazz = MakeGlobalRefOrDie(env, runnableClazz);
+    gRunnableClassInfo.run = GetMethodIDOrDie(env, runnableClazz, "run", "()V");
+
+    LOG_ALWAYS_FATAL_IF(env->GetJavaVM(&gVm) != 0);
+
     AudioSystem::addErrorCallback(android_media_AudioSystem_error_callback);
 
     RegisterMethodsOrDie(env, kClassPathName, gMethods, NELEM(gMethods));
diff --git a/media/java/android/media/AudioSystem.java b/media/java/android/media/AudioSystem.java
index d148afd3c15d..52b5ff77c031 100644
--- a/media/java/android/media/AudioSystem.java
+++ b/media/java/android/media/AudioSystem.java
@@ -2649,4 +2649,11 @@ public class AudioSystem
      * @hide
      */
     public static native boolean isBluetoothVariableLatencyEnabled();
+
+    /**
+     * Register a native listener for system property sysprop
+     * @param callback the listener which fires when the property changes
+     * @hide
+     */
+    public static native void listenForSystemPropertyChange(String sysprop, Runnable callback);
 }
diff --git a/services/core/java/com/android/server/audio/AudioService.java b/services/core/java/com/android/server/audio/AudioService.java
index 74d218cba7ab..41b984b67d02 100644
--- a/services/core/java/com/android/server/audio/AudioService.java
+++ b/services/core/java/com/android/server/audio/AudioService.java
@@ -734,6 +734,8 @@ public class AudioService extends IAudioService.Stub
     // Broadcast receiver for device connections intent broadcasts
     private final BroadcastReceiver mReceiver = new AudioServiceBroadcastReceiver();
 
+    private final Executor mAudioServerLifecycleExecutor;
+
     private IMediaProjectionManager mProjectionService; // to validate projection token
 
     /** Interface for UserManagerService. */
@@ -1052,7 +1054,8 @@ public class AudioService extends IAudioService.Stub
                               audioserverPermissions() ?
                                 initializeAudioServerPermissionProvider(
                                     context, audioPolicyFacade, audioserverLifecycleExecutor) :
-                                    null
+                                    null,
+                              audioserverLifecycleExecutor
                               );
         }
 
@@ -1138,13 +1141,16 @@ public class AudioService extends IAudioService.Stub
      *               {@link AudioSystemThread} is created as the messaging thread instead.
      * @param appOps {@link AppOpsManager} system service
      * @param enforcer Used for permission enforcing
+     * @param permissionProvider Used to push permissions to audioserver
+     * @param audioserverLifecycleExecutor Used for tasks managing audioserver lifecycle
      */
     @RequiresPermission(Manifest.permission.READ_DEVICE_CONFIG)
     public AudioService(Context context, AudioSystemAdapter audioSystem,
             SystemServerAdapter systemServer, SettingsAdapter settings,
             AudioVolumeGroupHelperBase audioVolumeGroupHelper, AudioPolicyFacade audioPolicy,
             @Nullable Looper looper, AppOpsManager appOps, @NonNull PermissionEnforcer enforcer,
-            /* @NonNull */ AudioServerPermissionProvider permissionProvider) {
+            /* @NonNull */ AudioServerPermissionProvider permissionProvider,
+            Executor audioserverLifecycleExecutor) {
         super(enforcer);
         sLifecycleLogger.enqueue(new EventLogger.StringEvent("AudioService()"));
         mContext = context;
@@ -1152,6 +1158,7 @@ public class AudioService extends IAudioService.Stub
         mAppOps = appOps;
 
         mPermissionProvider = permissionProvider;
+        mAudioServerLifecycleExecutor = audioserverLifecycleExecutor;
 
         mAudioSystem = audioSystem;
         mSystemServer = systemServer;
@@ -1163,6 +1170,34 @@ public class AudioService extends IAudioService.Stub
         mBroadcastHandlerThread = new HandlerThread("AudioService Broadcast");
         mBroadcastHandlerThread.start();
 
+        // Listen to permission invalidations for the PermissionProvider
+        if (audioserverPermissions()) {
+            final Handler broadcastHandler = mBroadcastHandlerThread.getThreadHandler();
+            mAudioSystem.listenForSystemPropertyChange(PermissionManager.CACHE_KEY_PACKAGE_INFO,
+                    new Runnable() {
+                        // Roughly chosen to be long enough to suppress the autocork behavior
+                        // of the permission cache (50ms), and longer than the task could reasonably
+                        // take, even with many packages and users, while not introducing visible
+                        // permission leaks - since the app needs to restart, and trigger an action
+                        // which requires permissions from audioserver before this delay.
+                        // For RECORD_AUDIO, we are additionally protected by appops.
+                        final long UPDATE_DELAY_MS = 110;
+                        final AtomicLong scheduledUpdateTimestamp = new AtomicLong(0);
+                        @Override
+                        public void run() {
+                            var currentTime = SystemClock.uptimeMillis();
+                            if (currentTime > scheduledUpdateTimestamp.get()) {
+                                scheduledUpdateTimestamp.set(currentTime + UPDATE_DELAY_MS);
+                                broadcastHandler.postAtTime( () ->
+                                        mAudioServerLifecycleExecutor.execute(mPermissionProvider
+                                            ::onPermissionStateChanged),
+                                        currentTime + UPDATE_DELAY_MS
+                                    );
+                            }
+                        }
+            });
+        }
+
         mDeviceBroker = new AudioDeviceBroker(mContext, this, mAudioSystem);
 
         mIsSingleVolume = AudioSystem.isSingleVolume(context);
@@ -11972,29 +12007,6 @@ public class AudioService extends IAudioService.Stub
             provider.onServiceStart(audioPolicy.getPermissionController());
         });
 
-        // Set up event listeners
-        // Must be kept in sync with PermissionManager
-        Runnable cacheSysPropHandler = new Runnable() {
-            private AtomicReference<SystemProperties.Handle> mHandle = new AtomicReference();
-            private AtomicLong mNonce = new AtomicLong();
-            @Override
-            public void run() {
-                if (mHandle.get() == null) {
-                    // Cache the handle
-                    mHandle.compareAndSet(null, SystemProperties.find(
-                            PermissionManager.CACHE_KEY_PACKAGE_INFO));
-                }
-                long nonce;
-                SystemProperties.Handle ref;
-                if ((ref = mHandle.get()) != null && (nonce = ref.getLong(0)) != 0 &&
-                        mNonce.getAndSet(nonce) != nonce) {
-                    audioserverExecutor.execute(() -> provider.onPermissionStateChanged());
-                }
-            }
-        };
-
-        SystemProperties.addChangeCallback(cacheSysPropHandler);
-
         IntentFilter packageUpdateFilter = new IntentFilter();
         packageUpdateFilter.addAction(ACTION_PACKAGE_ADDED);
         packageUpdateFilter.addAction(ACTION_PACKAGE_REMOVED);
diff --git a/services/core/java/com/android/server/audio/AudioSystemAdapter.java b/services/core/java/com/android/server/audio/AudioSystemAdapter.java
index 7f4bc74bd59e..d083c68c4c2c 100644
--- a/services/core/java/com/android/server/audio/AudioSystemAdapter.java
+++ b/services/core/java/com/android/server/audio/AudioSystemAdapter.java
@@ -748,6 +748,10 @@ public class AudioSystemAdapter implements AudioSystem.RoutingUpdateCallback,
         return AudioSystem.setMasterMute(mute);
     }
 
+    public void listenForSystemPropertyChange(String systemPropertyName, Runnable callback) {
+        AudioSystem.listenForSystemPropertyChange(systemPropertyName, callback);
+    }
+
     /**
      * Part of AudioService dump
      * @param pw
diff --git a/services/tests/servicestests/src/com/android/server/audio/AbsoluteVolumeBehaviorTest.java b/services/tests/servicestests/src/com/android/server/audio/AbsoluteVolumeBehaviorTest.java
index 758c84a26dcd..ef9580c54de6 100644
--- a/services/tests/servicestests/src/com/android/server/audio/AbsoluteVolumeBehaviorTest.java
+++ b/services/tests/servicestests/src/com/android/server/audio/AbsoluteVolumeBehaviorTest.java
@@ -101,7 +101,7 @@ public class AbsoluteVolumeBehaviorTest {
         mAudioService = new AudioService(mContext, mSpyAudioSystem, mSystemServer,
                 mSettingsAdapter, mAudioVolumeGroupHelper, mMockAudioPolicy,
                 mTestLooper.getLooper(), mock(AppOpsManager.class), mock(PermissionEnforcer.class),
-                mock(AudioServerPermissionProvider.class)) {
+                mock(AudioServerPermissionProvider.class), r -> r.run()) {
             @Override
             public int getDeviceForStream(int stream) {
                 return AudioSystem.DEVICE_OUT_SPEAKER;
diff --git a/services/tests/servicestests/src/com/android/server/audio/AudioDeviceVolumeManagerTest.java b/services/tests/servicestests/src/com/android/server/audio/AudioDeviceVolumeManagerTest.java
index 2cb02bdd2806..464515632997 100644
--- a/services/tests/servicestests/src/com/android/server/audio/AudioDeviceVolumeManagerTest.java
+++ b/services/tests/servicestests/src/com/android/server/audio/AudioDeviceVolumeManagerTest.java
@@ -78,7 +78,7 @@ public class AudioDeviceVolumeManagerTest {
         mAudioService = new AudioService(mContext, mSpyAudioSystem, mSystemServer,
                 mSettingsAdapter, mAudioVolumeGroupHelper, mAudioPolicyMock,
                 mTestLooper.getLooper(), mock(AppOpsManager.class), mock(PermissionEnforcer.class),
-                mock(AudioServerPermissionProvider.class)) {
+                mock(AudioServerPermissionProvider.class), r -> r.run()) {
             @Override
             public int getDeviceForStream(int stream) {
                 return AudioSystem.DEVICE_OUT_SPEAKER;
diff --git a/services/tests/servicestests/src/com/android/server/audio/AudioServiceTest.java b/services/tests/servicestests/src/com/android/server/audio/AudioServiceTest.java
index 037c3c00443c..b7100ea00a40 100644
--- a/services/tests/servicestests/src/com/android/server/audio/AudioServiceTest.java
+++ b/services/tests/servicestests/src/com/android/server/audio/AudioServiceTest.java
@@ -87,7 +87,7 @@ public class AudioServiceTest {
                 .thenReturn(AppOpsManager.MODE_ALLOWED);
         mAudioService = new AudioService(mContext, mSpyAudioSystem, mSpySystemServer,
                 mSettingsAdapter, mAudioVolumeGroupHelper, mMockAudioPolicy, null,
-                mMockAppOpsManager, mMockPermissionEnforcer, mMockPermissionProvider);
+                mMockAppOpsManager, mMockPermissionEnforcer, mMockPermissionProvider, r -> r.run());
     }
 
     /**
diff --git a/services/tests/servicestests/src/com/android/server/audio/DeviceVolumeBehaviorTest.java b/services/tests/servicestests/src/com/android/server/audio/DeviceVolumeBehaviorTest.java
index 27b552fa7cdd..746645a8c585 100644
--- a/services/tests/servicestests/src/com/android/server/audio/DeviceVolumeBehaviorTest.java
+++ b/services/tests/servicestests/src/com/android/server/audio/DeviceVolumeBehaviorTest.java
@@ -78,7 +78,7 @@ public class DeviceVolumeBehaviorTest {
         mAudioService = new AudioService(mContext, mAudioSystem, mSystemServer,
                 mSettingsAdapter, mAudioVolumeGroupHelper, mAudioPolicyMock,
                 mTestLooper.getLooper(), mock(AppOpsManager.class), mock(PermissionEnforcer.class),
-                mock(AudioServerPermissionProvider.class));
+                mock(AudioServerPermissionProvider.class), r -> r.run());
         mTestLooper.dispatchAll();
     }
 
diff --git a/services/tests/servicestests/src/com/android/server/audio/VolumeHelperTest.java b/services/tests/servicestests/src/com/android/server/audio/VolumeHelperTest.java
index 8e34ee1b6a42..e45ab319146c 100644
--- a/services/tests/servicestests/src/com/android/server/audio/VolumeHelperTest.java
+++ b/services/tests/servicestests/src/com/android/server/audio/VolumeHelperTest.java
@@ -160,7 +160,7 @@ public class VolumeHelperTest {
                 @NonNull PermissionEnforcer enforcer,
                 AudioServerPermissionProvider permissionProvider) {
             super(context, audioSystem, systemServer, settings, audioVolumeGroupHelper,
-                    audioPolicy, looper, appOps, enforcer, permissionProvider);
+                    audioPolicy, looper, appOps, enforcer, permissionProvider, r -> r.run());
         }
 
         public void setDeviceForStream(int stream, int device) {