Add Unique Identifier for MediaSessionRecord(s)

- This is part of the work done for b/295518668 and b/297052684 we need
to differentiate between MediaSessionRecords owned by the same app.

- For example an app should be allowed to go to the foreground if it
has at least an active media session in a user-engaged state.

- In case an app has 2 active media sessions that are in a user-engaged
states, moving one of them to user-not-engaged state shouldn't prevent
the app from being in the foreground because of the other session.

Bug: 322776229
Test: adb shell dumpsys media_session
Change-Id: I0958d9b955468757a94eb82c53fde29eb243c13b

4 files changed, 63 insertions, 11 deletions

diff --git a/services/core/java/com/android/server/media/MediaSession2Record.java b/services/core/java/com/android/server/media/MediaSession2Record.java
index db70ce281eb5..a110e5637f82 100644
--- a/services/core/java/com/android/server/media/MediaSession2Record.java
+++ b/services/core/java/com/android/server/media/MediaSession2Record.java
@@ -40,6 +40,7 @@ public class MediaSession2Record implements MediaSessionRecordImpl {
     private static final boolean DEBUG = Log.isLoggable(TAG, Log.DEBUG);
     private final Object mLock = new Object();
 
+    private final int mUniqueId;
     @GuardedBy("mLock")
     private final Session2Token mSessionToken;
     @GuardedBy("mLock")
@@ -63,11 +64,13 @@ public class MediaSession2Record implements MediaSessionRecordImpl {
             MediaSessionService service,
             Looper handlerLooper,
             int pid,
-            int policies) {
+            int policies,
+            int uniqueId) {
         // The lock is required to prevent `Controller2Callback` from using partially initialized
         // `MediaSession2Record.this`.
         synchronized (mLock) {
             mSessionToken = sessionToken;
+            mUniqueId = uniqueId;
             mService = service;
             mHandlerExecutor = new HandlerExecutor(new Handler(handlerLooper));
             mController = new MediaController2.Builder(service.getContext(), sessionToken)
@@ -98,6 +101,13 @@ public class MediaSession2Record implements MediaSessionRecordImpl {
     }
 
     @Override
+    public int getUniqueId() {
+        synchronized (mLock) {
+            return mUniqueId;
+        }
+    }
+
+    @Override
     public String getPackageName() {
         return mSessionToken.getPackageName();
     }
@@ -200,6 +210,7 @@ public class MediaSession2Record implements MediaSessionRecordImpl {
 
     @Override
     public void dump(PrintWriter pw, String prefix) {
+        pw.println(prefix + "uniqueId=" + mUniqueId);
         pw.println(prefix + "token=" + mSessionToken);
         pw.println(prefix + "controller=" + mController);
 
@@ -209,8 +220,7 @@ public class MediaSession2Record implements MediaSessionRecordImpl {
 
     @Override
     public String toString() {
-        // TODO(jaewan): Also add getId().
-        return getPackageName() + " (userId=" + getUserId() + ")";
+        return getPackageName() + "/" + mUniqueId + " (userId=" + getUserId() + ")";
     }
 
     private class Controller2Callback extends MediaController2.ControllerCallback {
diff --git a/services/core/java/com/android/server/media/MediaSessionRecord.java b/services/core/java/com/android/server/media/MediaSessionRecord.java
index 53f780e4d19e..15527041d8eb 100644
--- a/services/core/java/com/android/server/media/MediaSessionRecord.java
+++ b/services/core/java/com/android/server/media/MediaSessionRecord.java
@@ -173,6 +173,7 @@ public class MediaSessionRecord implements IBinder.DeathRecipient, MediaSessionR
     private final int mUserId;
     private final String mPackageName;
     private final String mTag;
+    private final int mUniqueId;
     private final Bundle mSessionInfo;
     private final ControllerStub mController;
     private final MediaSession.Token mSessionToken;
@@ -223,15 +224,25 @@ public class MediaSessionRecord implements IBinder.DeathRecipient, MediaSessionR
 
     private int mPolicies;
 
-    public MediaSessionRecord(int ownerPid, int ownerUid, int userId, String ownerPackageName,
-            ISessionCallback cb, String tag, Bundle sessionInfo,
-            MediaSessionService service, Looper handlerLooper, int policies)
+    public MediaSessionRecord(
+            int ownerPid,
+            int ownerUid,
+            int userId,
+            String ownerPackageName,
+            ISessionCallback cb,
+            String tag,
+            int uniqueId,
+            Bundle sessionInfo,
+            MediaSessionService service,
+            Looper handlerLooper,
+            int policies)
             throws RemoteException {
         mOwnerPid = ownerPid;
         mOwnerUid = ownerUid;
         mUserId = userId;
         mPackageName = ownerPackageName;
         mTag = tag;
+        mUniqueId = uniqueId;
         mSessionInfo = sessionInfo;
         mController = new ControllerStub();
         mSessionToken = new MediaSession.Token(ownerUid, mController);
@@ -292,6 +303,16 @@ public class MediaSessionRecord implements IBinder.DeathRecipient, MediaSessionR
     }
 
     /**
+     * Get the unique id of this session record.
+     *
+     * @return a unique id of this session record.
+     */
+    @Override
+    public int getUniqueId() {
+        return mUniqueId;
+    }
+
+    /**
      * Get the info for this session.
      *
      * @return Info that identifies this session.
@@ -703,7 +724,7 @@ public class MediaSessionRecord implements IBinder.DeathRecipient, MediaSessionR
 
     @Override
     public String toString() {
-        return mPackageName + "/" + mTag + " (userId=" + mUserId + ")";
+        return mPackageName + "/" + mTag + "/" + mUniqueId + " (userId=" + mUserId + ")";
     }
 
     @Override
diff --git a/services/core/java/com/android/server/media/MediaSessionRecordImpl.java b/services/core/java/com/android/server/media/MediaSessionRecordImpl.java
index 99c8ea93936e..e53a2dbe8101 100644
--- a/services/core/java/com/android/server/media/MediaSessionRecordImpl.java
+++ b/services/core/java/com/android/server/media/MediaSessionRecordImpl.java
@@ -32,6 +32,13 @@ import java.io.PrintWriter;
 public interface MediaSessionRecordImpl extends AutoCloseable {
 
     /**
+     * Get the unique id of this session record.
+     *
+     * @return a unique id of this session record.
+     */
+    int getUniqueId();
+
+    /**
      * Get the info for this session.
      *
      * @return Info that identifies this session.
diff --git a/services/core/java/com/android/server/media/MediaSessionService.java b/services/core/java/com/android/server/media/MediaSessionService.java
index 757b26c45ab1..9e98a5809650 100644
--- a/services/core/java/com/android/server/media/MediaSessionService.java
+++ b/services/core/java/com/android/server/media/MediaSessionService.java
@@ -106,6 +106,7 @@ import java.util.HashMap;
 import java.util.HashSet;
 import java.util.List;
 import java.util.Set;
+import java.util.concurrent.atomic.AtomicInteger;
 
 /**
  * System implementation of MediaSessionManager
@@ -155,6 +156,8 @@ public class MediaSessionService extends SystemService implements Monitor {
     /* Maps uid with all user engaging session tokens associated to it */
     private final SparseArray<Set<MediaSession.Token>> mUserEngagingSessions = new SparseArray<>();
 
+    private final AtomicInteger mNextMediaSessionRecordId = new AtomicInteger(1);
+
     // The FullUserRecord of the current users. (i.e. The foreground user that isn't a profile)
     // It's always not null after the MediaSessionService is started.
     private FullUserRecord mCurrentFullUserRecord;
@@ -193,7 +196,8 @@ public class MediaSessionService extends SystemService implements Monitor {
                                     MediaSessionService.this,
                                     mRecordThread.getLooper(),
                                     pid,
-                                    /* policies= */ 0);
+                                    /* policies= */ 0,
+                                    /* uniqueId= */ mNextMediaSessionRecordId.getAndIncrement());
                     synchronized (mLock) {
                         FullUserRecord user = getFullUserRecordLocked(record.getUserId());
                         if (user != null) {
@@ -794,9 +798,19 @@ public class MediaSessionService extends SystemService implements Monitor {
 
             final MediaSessionRecord session;
             try {
-                session = new MediaSessionRecord(callerPid, callerUid, userId,
-                        callerPackageName, cb, tag, sessionInfo, this,
-                        mRecordThread.getLooper(), policies);
+                session =
+                        new MediaSessionRecord(
+                                callerPid,
+                                callerUid,
+                                userId,
+                                callerPackageName,
+                                cb,
+                                tag,
+                                /* uniqueId= */ mNextMediaSessionRecordId.getAndIncrement(),
+                                sessionInfo,
+                                this,
+                                mRecordThread.getLooper(),
+                                policies);
             } catch (RemoteException e) {
                 throw new RuntimeException("Media Session owner died prematurely.", e);
             }