Merge "Ensure backup doesn't reuse ack tokens nearby in time" into oc-dr1-dev

import com.android.server.SystemConfig;

import com.android.server.SystemService;

import com.android.server.backup.PackageManagerBackupAgent.Metadata;

import com.android.server.power.BatterySaverPolicy.ServiceType;

import libcore.io.IoUtils;

import java.io.BufferedInputStream;

    final SparseArray<Operation> mCurrentOperations = new SparseArray<Operation>();

    final Object mCurrentOpLock = new Object();

    final Random mTokenGenerator = new Random();

    final AtomicInteger mNextToken = new AtomicInteger();

    final SparseArray<AdbParams> mAdbBackupRestoreConfirmations = new SparseArray<AdbParams>();

    @GuardedBy("mQueueLock")

    ArrayList<FullBackupEntry> mFullBackupQueue;

    // Utility: build a new random integer token

    // Utility: build a new random integer token.  The low bits are the ordinal of the

    // operation for near-time uniqueness, and the upper bits are random for app-

    // side unpredictability.

    @Override

    public int generateRandomIntegerToken() {

        int token;

        do {

            synchronized (mTokenGenerator) {

                token = mTokenGenerator.nextInt();

            }

        } while (token < 0);

        int token = mTokenGenerator.nextInt() & ~0xFF;

        token |= (mNextToken.incrementAndGet() & 0xFF);

        return token;

    }