From bf01d9b7a3cd3b7ebc40c0264667c77e7ecd4330 Mon Sep 17 00:00:00 2001
From: Sungsoo Lim <sungsoo@google.com>
Date: Wed, 16 Dec 2020 14:29:20 +0900
Subject: [PATCH] Cache stream volumes to prevent ANR

MediaRourter uses main thread for internal operations, and ANR could
happens if AudioService is not running when MediaRouter tried to get
stream volumes. This CL avoids such ANR by caching stream volumes.

Bug: 170327593
Test: manually
Change-Id: I2560eda6436a89c754224cc835e48fe4f5e36827
---
 media/java/android/media/MediaRouter.java | 26 ++++++++++++++++-------
 1 file changed, 18 insertions(+), 8 deletions(-)

diff --git a/media/java/android/media/MediaRouter.java b/media/java/android/media/MediaRouter.java
index 4940c7647dbc6..36f7bed03bcd9 100644
--- a/media/java/android/media/MediaRouter.java
+++ b/media/java/android/media/MediaRouter.java
@@ -43,6 +43,7 @@ import android.os.RemoteException;
 import android.os.ServiceManager;
 import android.os.UserHandle;
 import android.text.TextUtils;
+import android.util.ArrayMap;
 import android.util.Log;
 import android.view.Display;
 import android.view.DisplayAddress;
@@ -54,6 +55,7 @@ import java.lang.annotation.RetentionPolicy;
 import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.List;
+import java.util.Map;
 import java.util.Objects;
 import java.util.concurrent.CopyOnWriteArrayList;
 
@@ -111,6 +113,8 @@ public class MediaRouter {
         IMediaRouterClient mClient;
         MediaRouterClientState mClientState;
 
+        Map<Integer, Integer> mStreamVolume = new ArrayMap<>();
+
         final IAudioRoutesObserver.Stub mAudioRoutesObserver = new IAudioRoutesObserver.Stub() {
             @Override
             public void dispatchAudioRoutesChanged(final AudioRoutesInfo newRoutes) {
@@ -262,6 +266,17 @@ public class MediaRouter {
             mCurAudioRoutesInfo.bluetoothName = newRoutes.bluetoothName;
         }
 
+        int getStreamVolume(int streamType) {
+            if (!mStreamVolume.containsKey(streamType)) {
+                try {
+                    mStreamVolume.put(streamType, mAudioService.getStreamVolume(streamType));
+                } catch (RemoteException e) {
+                    Log.e(TAG, "Error getting local stream volume", e);
+                }
+            }
+            return mStreamVolume.get(streamType);
+        }
+
         boolean isBluetoothA2dpOn() {
             try {
                 return mBluetoothA2dpRoute != null && mAudioService.isBluetoothA2dpOn();
@@ -1976,13 +1991,7 @@ public class MediaRouter {
          */
         public int getVolume() {
             if (mPlaybackType == PLAYBACK_TYPE_LOCAL) {
-                int vol = 0;
-                try {
-                    vol = sStatic.mAudioService.getStreamVolume(mPlaybackStream);
-                } catch (RemoteException e) {
-                    Log.e(TAG, "Error getting local stream volume", e);
-                }
-                return vol;
+                return sStatic.getStreamVolume(mPlaybackStream);
             } else {
                 return mVolume;
             }
@@ -3139,11 +3148,12 @@ public class MediaRouter {
             if (intent.getAction().equals(AudioManager.VOLUME_CHANGED_ACTION)) {
                 final int streamType = intent.getIntExtra(AudioManager.EXTRA_VOLUME_STREAM_TYPE,
                         -1);
+                final int newVolume = intent.getIntExtra(AudioManager.EXTRA_VOLUME_STREAM_VALUE, 0);
+                sStatic.mStreamVolume.put(streamType, newVolume);
                 if (streamType != AudioManager.STREAM_MUSIC) {
                     return;
                 }
 
-                final int newVolume = intent.getIntExtra(AudioManager.EXTRA_VOLUME_STREAM_VALUE, 0);
                 final int oldVolume = intent.getIntExtra(
                         AudioManager.EXTRA_PREV_VOLUME_STREAM_VALUE, 0);
                 if (newVolume != oldVolume) {