content: /*
   * Copyright (C) 2013 The Android Open Source Project
   *
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   *      http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  
  package com.android.server.wifi;
  
  import android.annotation.NonNull;
  import android.net.wifi.ITrafficStateCallback;
  import android.net.wifi.WifiManager;
  import android.os.Handler;
  import android.os.IBinder;
  import android.os.Looper;
  import android.os.RemoteException;
  import android.util.Log;
  
  import com.android.server.wifi.util.ExternalCallbackTracker;
  
  import java.io.FileDescriptor;
  import java.io.PrintWriter;
  
  /**
   * Polls for traffic stats and notifies the clients
   */
  public class WifiTrafficPoller {
  
      private static final String TAG = "WifiTrafficPoller";
  
      private long mTxPkts;
      private long mRxPkts;
      /* Tracks last reported data activity */
      private int mDataActivity;
  
      private final ExternalCallbackTracker<ITrafficStateCallback> mRegisteredCallbacks;
  
      WifiTrafficPoller(@NonNull Looper looper) {
          mRegisteredCallbacks = new ExternalCallbackTracker<ITrafficStateCallback>(
                  new Handler(looper));
      }
  
      /**
       * Add a new callback to the traffic poller.
       */
      public void addCallback(IBinder binder, ITrafficStateCallback callback,
                              int callbackIdentifier) {
          if (!mRegisteredCallbacks.add(binder, callback, callbackIdentifier)) {
              Log.e(TAG, "Failed to add callback");
              return;
          }
      }
  
      /**
       * Remove an existing callback from the traffic poller.
       */
      public void removeCallback(int callbackIdentifier) {
          mRegisteredCallbacks.remove(callbackIdentifier);
      }
  
      void notifyOnDataActivity(long txPkts, long rxPkts) {
          long sent, received;
          long preTxPkts = mTxPkts, preRxPkts = mRxPkts;
          int dataActivity = WifiManager.TrafficStateCallback.DATA_ACTIVITY_NONE;
          mTxPkts = txPkts;
          mRxPkts = rxPkts;
  
          if (preTxPkts > 0 || preRxPkts > 0) {
              sent = mTxPkts - preTxPkts;
              received = mRxPkts - preRxPkts;
              if (sent > 0) {
                  dataActivity |= WifiManager.TrafficStateCallback.DATA_ACTIVITY_OUT;
              }
              if (received > 0) {
                  dataActivity |= WifiManager.TrafficStateCallback.DATA_ACTIVITY_IN;
              }
  
              if (dataActivity != mDataActivity) {
                  mDataActivity = dataActivity;
                  for (ITrafficStateCallback callback : mRegisteredCallbacks.getCallbacks()) {
                      try {
                          callback.onStateChanged(mDataActivity);
                      } catch (RemoteException e) {
                          // Failed to reach, skip
                          // Client removal is handled in WifiService
                      }
                  }
              }
          }
      }
  
      /**
       * Dump method for traffic poller.
       */
      public void dump(FileDescriptor fd, PrintWriter pw, String[] args) {
          pw.println("mTxPkts " + mTxPkts);
          pw.println("mRxPkts " + mRxPkts);
          pw.println("mDataActivity " + mDataActivity);
          pw.println("mRegisteredCallbacks " + mRegisteredCallbacks.getNumCallbacks());
      }
  
  }
  