WifiTrafficPoller.java revision 8e14dcb9dc38149b4672eceb3fe22287ea4343a0 
1/*
2 * Copyright (C) 2013 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17package com.android.server.wifi;
18
19import static android.net.NetworkInfo.DetailedState.CONNECTED;
20
21import android.content.BroadcastReceiver;
22import android.content.Context;
23import android.content.Intent;
24import android.content.IntentFilter;
25import android.net.NetworkInfo;
26import android.net.TrafficStats;
27import android.net.wifi.WifiManager;
28import android.os.Handler;
29import android.os.Looper;
30import android.os.Message;
31import android.os.Messenger;
32import android.os.RemoteException;
33import android.util.Log;
34
35import java.io.FileDescriptor;
36import java.io.PrintWriter;
37import java.util.ArrayList;
38import java.util.List;
39import java.util.concurrent.atomic.AtomicBoolean;
40
41/* Polls for traffic stats and notifies the clients */
42final class WifiTrafficPoller {
43
44    private boolean DBG = false;
45    private boolean VDBG = false;
46
47    private final String TAG = "WifiTrafficPoller";
48    /**
49     * Interval in milliseconds between polling for traffic
50     * statistics
51     */
52    private static final int POLL_TRAFFIC_STATS_INTERVAL_MSECS = 1000;
53
54    private static final int ENABLE_TRAFFIC_STATS_POLL  = 1;
55    private static final int TRAFFIC_STATS_POLL         = 2;
56    private static final int ADD_CLIENT                 = 3;
57    private static final int REMOVE_CLIENT              = 4;
58
59    private boolean mEnableTrafficStatsPoll = false;
60    private int mTrafficStatsPollToken = 0;
61    private long mTxPkts;
62    private long mRxPkts;
63    /* Tracks last reported data activity */
64    private int mDataActivity;
65
66    private final List<Messenger> mClients = new ArrayList<Messenger>();
67    // err on the side of updating at boot since screen on broadcast may be missed
68    // the first time
69    private AtomicBoolean mScreenOn = new AtomicBoolean(true);
70    private final TrafficHandler mTrafficHandler;
71    private NetworkInfo mNetworkInfo;
72    private final String mInterface;
73
74    WifiTrafficPoller(Context context, Looper looper, String iface) {
75        mInterface = iface;
76        mTrafficHandler = new TrafficHandler(looper);
77
78        IntentFilter filter = new IntentFilter();
79        filter.addAction(WifiManager.NETWORK_STATE_CHANGED_ACTION);
80        filter.addAction(Intent.ACTION_SCREEN_OFF);
81        filter.addAction(Intent.ACTION_SCREEN_ON);
82
83        context.registerReceiver(
84                new BroadcastReceiver() {
85                    @Override
86                    public void onReceive(Context context, Intent intent) {
87                        if (intent.getAction().equals(
88                                WifiManager.NETWORK_STATE_CHANGED_ACTION)) {
89                            mNetworkInfo = (NetworkInfo) intent.getParcelableExtra(
90                                    WifiManager.EXTRA_NETWORK_INFO);
91                        } else if (intent.getAction().equals(Intent.ACTION_SCREEN_OFF)) {
92                            mScreenOn.set(false);
93                        } else if (intent.getAction().equals(Intent.ACTION_SCREEN_ON)) {
94                            mScreenOn.set(true);
95                        }
96                        evaluateTrafficStatsPolling();
97                    }
98                }, filter);
99    }
100
101    void addClient(Messenger client) {
102        Message.obtain(mTrafficHandler, ADD_CLIENT, client).sendToTarget();
103    }
104
105    void removeClient(Messenger client) {
106        Message.obtain(mTrafficHandler, REMOVE_CLIENT, client).sendToTarget();
107    }
108
109    void enableVerboseLogging(int verbose) {
110        if (verbose > 0 ) {
111            DBG = true;
112        } else {
113            DBG = false;
114        }
115    }
116
117    private class TrafficHandler extends Handler {
118        public TrafficHandler(Looper looper) {
119            super(looper);
120        }
121
122        public void handleMessage(Message msg) {
123            switch (msg.what) {
124                case ENABLE_TRAFFIC_STATS_POLL:
125                    mEnableTrafficStatsPoll = (msg.arg1 == 1);
126                    if (DBG) {
127                        Log.e(TAG, "ENABLE_TRAFFIC_STATS_POLL "
128                                + mEnableTrafficStatsPoll + " Token "
129                                + Integer.toString(mTrafficStatsPollToken));
130                    }
131                    mTrafficStatsPollToken++;
132                    if (mEnableTrafficStatsPoll) {
133                        notifyOnDataActivity();
134                        sendMessageDelayed(Message.obtain(this, TRAFFIC_STATS_POLL,
135                                mTrafficStatsPollToken, 0), POLL_TRAFFIC_STATS_INTERVAL_MSECS);
136                    }
137                    break;
138                case TRAFFIC_STATS_POLL:
139                    if (VDBG) {
140                        Log.e(TAG, "TRAFFIC_STATS_POLL "
141                                + mEnableTrafficStatsPoll + " Token "
142                                + Integer.toString(mTrafficStatsPollToken)
143                                + " num clients " + mClients.size());
144                    }
145                    if (msg.arg1 == mTrafficStatsPollToken) {
146                        notifyOnDataActivity();
147                        sendMessageDelayed(Message.obtain(this, TRAFFIC_STATS_POLL,
148                                mTrafficStatsPollToken, 0), POLL_TRAFFIC_STATS_INTERVAL_MSECS);
149                    }
150                    break;
151                case ADD_CLIENT:
152                    mClients.add((Messenger) msg.obj);
153                    if (DBG) {
154                        Log.e(TAG, "ADD_CLIENT: "
155                                + Integer.toString(mClients.size()));
156                    }
157                    break;
158                case REMOVE_CLIENT:
159                    mClients.remove(msg.obj);
160                    break;
161            }
162
163        }
164    }
165
166    private void evaluateTrafficStatsPolling() {
167        Message msg;
168        if (mNetworkInfo == null) return;
169        if (mNetworkInfo.getDetailedState() == CONNECTED && mScreenOn.get()) {
170            msg = Message.obtain(mTrafficHandler,
171                    ENABLE_TRAFFIC_STATS_POLL, 1, 0);
172        } else {
173            msg = Message.obtain(mTrafficHandler,
174                    ENABLE_TRAFFIC_STATS_POLL, 0, 0);
175        }
176        msg.sendToTarget();
177    }
178
179    private void notifyOnDataActivity() {
180        long sent, received;
181        long preTxPkts = mTxPkts, preRxPkts = mRxPkts;
182        int dataActivity = WifiManager.DATA_ACTIVITY_NONE;
183
184        mTxPkts = TrafficStats.getTxPackets(mInterface);
185        mRxPkts = TrafficStats.getRxPackets(mInterface);
186
187        if (VDBG) {
188            Log.e(TAG, " packet count Tx="
189                    + Long.toString(mTxPkts)
190                    + " Rx="
191                    + Long.toString(mRxPkts));
192        }
193
194        if (preTxPkts > 0 || preRxPkts > 0) {
195            sent = mTxPkts - preTxPkts;
196            received = mRxPkts - preRxPkts;
197            if (sent > 0) {
198                dataActivity |= WifiManager.DATA_ACTIVITY_OUT;
199            }
200            if (received > 0) {
201                dataActivity |= WifiManager.DATA_ACTIVITY_IN;
202            }
203
204            if (dataActivity != mDataActivity && mScreenOn.get()) {
205                mDataActivity = dataActivity;
206                if (DBG) {
207                    Log.e(TAG, "notifying of data activity "
208                            + Integer.toString(mDataActivity));
209                }
210                for (Messenger client : mClients) {
211                    Message msg = Message.obtain();
212                    msg.what = WifiManager.DATA_ACTIVITY_NOTIFICATION;
213                    msg.arg1 = mDataActivity;
214                    try {
215                        client.send(msg);
216                    } catch (RemoteException e) {
217                        // Failed to reach, skip
218                        // Client removal is handled in WifiService
219                    }
220                }
221            }
222        }
223    }
224
225    void dump(FileDescriptor fd, PrintWriter pw, String[] args) {
226        pw.println("mEnableTrafficStatsPoll " + mEnableTrafficStatsPoll);
227        pw.println("mTrafficStatsPollToken " + mTrafficStatsPollToken);
228        pw.println("mTxPkts " + mTxPkts);
229        pw.println("mRxPkts " + mRxPkts);
230        pw.println("mDataActivity " + mDataActivity);
231    }
232
233}
234