summaryrefslogtreecommitdiffstats
path: root/services/java/com/android/server/net/NetworkStatsService.java
blob: 5d6adc22685e4aa1fc1cc7084c41175c7aa0ac58 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
/*
 * Copyright (C) 2011 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.net;

import static android.Manifest.permission.ACCESS_NETWORK_STATE;
import static android.Manifest.permission.CONNECTIVITY_INTERNAL;
import static android.Manifest.permission.DUMP;
import static android.Manifest.permission.MODIFY_NETWORK_ACCOUNTING;
import static android.Manifest.permission.READ_NETWORK_USAGE_HISTORY;
import static android.content.Intent.ACTION_SHUTDOWN;
import static android.content.Intent.ACTION_UID_REMOVED;
import static android.content.Intent.ACTION_USER_REMOVED;
import static android.content.Intent.EXTRA_UID;
import static android.net.ConnectivityManager.ACTION_TETHER_STATE_CHANGED;
import static android.net.ConnectivityManager.CONNECTIVITY_ACTION_IMMEDIATE;
import static android.net.ConnectivityManager.isNetworkTypeMobile;
import static android.net.NetworkIdentity.COMBINE_SUBTYPE_ENABLED;
import static android.net.NetworkStats.IFACE_ALL;
import static android.net.NetworkStats.SET_ALL;
import static android.net.NetworkStats.SET_DEFAULT;
import static android.net.NetworkStats.SET_FOREGROUND;
import static android.net.NetworkStats.TAG_NONE;
import static android.net.NetworkStats.UID_ALL;
import static android.net.NetworkTemplate.buildTemplateMobileWildcard;
import static android.net.NetworkTemplate.buildTemplateWifiWildcard;
import static android.net.TrafficStats.KB_IN_BYTES;
import static android.net.TrafficStats.MB_IN_BYTES;
import static android.provider.Settings.Global.NETSTATS_DEV_BUCKET_DURATION;
import static android.provider.Settings.Global.NETSTATS_DEV_DELETE_AGE;
import static android.provider.Settings.Global.NETSTATS_DEV_PERSIST_BYTES;
import static android.provider.Settings.Global.NETSTATS_DEV_ROTATE_AGE;
import static android.provider.Settings.Global.NETSTATS_GLOBAL_ALERT_BYTES;
import static android.provider.Settings.Global.NETSTATS_POLL_INTERVAL;
import static android.provider.Settings.Global.NETSTATS_REPORT_XT_OVER_DEV;
import static android.provider.Settings.Global.NETSTATS_SAMPLE_ENABLED;
import static android.provider.Settings.Global.NETSTATS_TIME_CACHE_MAX_AGE;
import static android.provider.Settings.Global.NETSTATS_UID_BUCKET_DURATION;
import static android.provider.Settings.Global.NETSTATS_UID_DELETE_AGE;
import static android.provider.Settings.Global.NETSTATS_UID_PERSIST_BYTES;
import static android.provider.Settings.Global.NETSTATS_UID_ROTATE_AGE;
import static android.provider.Settings.Global.NETSTATS_UID_TAG_BUCKET_DURATION;
import static android.provider.Settings.Global.NETSTATS_UID_TAG_DELETE_AGE;
import static android.provider.Settings.Global.NETSTATS_UID_TAG_PERSIST_BYTES;
import static android.provider.Settings.Global.NETSTATS_UID_TAG_ROTATE_AGE;
import static android.telephony.PhoneStateListener.LISTEN_DATA_CONNECTION_STATE;
import static android.telephony.PhoneStateListener.LISTEN_NONE;
import static android.text.format.DateUtils.DAY_IN_MILLIS;
import static android.text.format.DateUtils.HOUR_IN_MILLIS;
import static android.text.format.DateUtils.MINUTE_IN_MILLIS;
import static android.text.format.DateUtils.SECOND_IN_MILLIS;
import static com.android.internal.util.ArrayUtils.appendElement;
import static com.android.internal.util.ArrayUtils.contains;
import static com.android.internal.util.Preconditions.checkNotNull;
import static com.android.server.NetworkManagementService.LIMIT_GLOBAL_ALERT;
import static com.android.server.NetworkManagementSocketTagger.resetKernelUidStats;
import static com.android.server.NetworkManagementSocketTagger.setKernelCounterSet;

import android.app.AlarmManager;
import android.app.IAlarmManager;
import android.app.PendingIntent;
import android.content.BroadcastReceiver;
import android.content.ContentResolver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.content.pm.ApplicationInfo;
import android.content.pm.PackageManager;
import android.net.IConnectivityManager;
import android.net.INetworkManagementEventObserver;
import android.net.INetworkStatsService;
import android.net.INetworkStatsSession;
import android.net.LinkProperties;
import android.net.NetworkIdentity;
import android.net.NetworkInfo;
import android.net.NetworkState;
import android.net.NetworkStats;
import android.net.NetworkStats.NonMonotonicObserver;
import android.net.NetworkStatsHistory;
import android.net.NetworkTemplate;
import android.net.TrafficStats;
import android.os.Binder;
import android.os.DropBoxManager;
import android.os.Environment;
import android.os.Handler;
import android.os.HandlerThread;
import android.os.INetworkManagementService;
import android.os.Message;
import android.os.PowerManager;
import android.os.RemoteException;
import android.os.SystemClock;
import android.os.UserHandle;
import android.provider.Settings;
import android.provider.Settings.Global;
import android.telephony.PhoneStateListener;
import android.telephony.TelephonyManager;
import android.util.EventLog;
import android.util.Log;
import android.util.MathUtils;
import android.util.NtpTrustedTime;
import android.util.Slog;
import android.util.SparseIntArray;
import android.util.TrustedTime;

import com.android.internal.annotations.VisibleForTesting;
import com.android.internal.util.ArrayUtils;
import com.android.internal.util.FileRotator;
import com.android.internal.util.IndentingPrintWriter;
import com.android.server.EventLogTags;
import com.android.server.connectivity.Tethering;
import com.google.android.collect.Maps;

import java.io.File;
import java.io.FileDescriptor;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.Arrays;
import java.util.HashMap;
import java.util.HashSet;
import java.util.List;

/**
 * Collect and persist detailed network statistics, and provide this data to
 * other system services.
 */
public class NetworkStatsService extends INetworkStatsService.Stub {
    private static final String TAG = "NetworkStats";
    private static final boolean LOGV = false;

    private static final int MSG_PERFORM_POLL = 1;
    private static final int MSG_UPDATE_IFACES = 2;
    private static final int MSG_REGISTER_GLOBAL_ALERT = 3;

    /** Flags to control detail level of poll event. */
    private static final int FLAG_PERSIST_NETWORK = 0x1;
    private static final int FLAG_PERSIST_UID = 0x2;
    private static final int FLAG_PERSIST_ALL = FLAG_PERSIST_NETWORK | FLAG_PERSIST_UID;
    private static final int FLAG_PERSIST_FORCE = 0x100;

    private static final String TAG_NETSTATS_ERROR = "netstats_error";

    private final Context mContext;
    private final INetworkManagementService mNetworkManager;
    private final AlarmManager mAlarmManager;
    private final TrustedTime mTime;
    private final TelephonyManager mTeleManager;
    private final NetworkStatsSettings mSettings;

    private final File mSystemDir;
    private final File mBaseDir;

    private final PowerManager.WakeLock mWakeLock;

    private IConnectivityManager mConnManager;

    @VisibleForTesting
    public static final String ACTION_NETWORK_STATS_POLL =
            "com.android.server.action.NETWORK_STATS_POLL";
    public static final String ACTION_NETWORK_STATS_UPDATED =
            "com.android.server.action.NETWORK_STATS_UPDATED";

    private PendingIntent mPollIntent;

    private static final String PREFIX_DEV = "dev";
    private static final String PREFIX_XT = "xt";
    private static final String PREFIX_UID = "uid";
    private static final String PREFIX_UID_TAG = "uid_tag";

    /**
     * Settings that can be changed externally.
     */
    public interface NetworkStatsSettings {
        public long getPollInterval();
        public long getTimeCacheMaxAge();
        public boolean getSampleEnabled();
        public boolean getReportXtOverDev();

        public static class Config {
            public final long bucketDuration;
            public final long rotateAgeMillis;
            public final long deleteAgeMillis;

            public Config(long bucketDuration, long rotateAgeMillis, long deleteAgeMillis) {
                this.bucketDuration = bucketDuration;
                this.rotateAgeMillis = rotateAgeMillis;
                this.deleteAgeMillis = deleteAgeMillis;
            }
        }

        public Config getDevConfig();
        public Config getXtConfig();
        public Config getUidConfig();
        public Config getUidTagConfig();

        public long getGlobalAlertBytes(long def);
        public long getDevPersistBytes(long def);
        public long getXtPersistBytes(long def);
        public long getUidPersistBytes(long def);
        public long getUidTagPersistBytes(long def);
    }

    private final Object mStatsLock = new Object();

    /** Set of currently active ifaces. */
    private HashMap<String, NetworkIdentitySet> mActiveIfaces = Maps.newHashMap();
    /** Current default active iface. */
    private String mActiveIface;
    /** Set of any ifaces associated with mobile networks since boot. */
    private String[] mMobileIfaces = new String[0];

    private final DropBoxNonMonotonicObserver mNonMonotonicObserver =
            new DropBoxNonMonotonicObserver();

    private NetworkStatsRecorder mDevRecorder;
    private NetworkStatsRecorder mXtRecorder;
    private NetworkStatsRecorder mUidRecorder;
    private NetworkStatsRecorder mUidTagRecorder;

    /** Cached {@link #mDevRecorder} stats. */
    private NetworkStatsCollection mDevStatsCached;
    /** Cached {@link #mXtRecorder} stats. */
    private NetworkStatsCollection mXtStatsCached;

    /** Current counter sets for each UID. */
    private SparseIntArray mActiveUidCounterSet = new SparseIntArray();

    /** Data layer operation counters for splicing into other structures. */
    private NetworkStats mUidOperations = new NetworkStats(0L, 10);

    private final Handler mHandler;

    private boolean mSystemReady;
    private long mPersistThreshold = 2 * MB_IN_BYTES;
    private long mGlobalAlertBytes;

    public NetworkStatsService(
            Context context, INetworkManagementService networkManager, IAlarmManager alarmManager) {
        this(context, networkManager, alarmManager, NtpTrustedTime.getInstance(context),
                getDefaultSystemDir(), new DefaultNetworkStatsSettings(context));
    }

    private static File getDefaultSystemDir() {
        return new File(Environment.getDataDirectory(), "system");
    }

    public NetworkStatsService(Context context, INetworkManagementService networkManager,
            IAlarmManager alarmManager, TrustedTime time, File systemDir,
            NetworkStatsSettings settings) {
        mContext = checkNotNull(context, "missing Context");
        mNetworkManager = checkNotNull(networkManager, "missing INetworkManagementService");
        mTime = checkNotNull(time, "missing TrustedTime");
        mTeleManager = checkNotNull(TelephonyManager.getDefault(), "missing TelephonyManager");
        mSettings = checkNotNull(settings, "missing NetworkStatsSettings");
        mAlarmManager = (AlarmManager) context.getSystemService(Context.ALARM_SERVICE);

        final PowerManager powerManager = (PowerManager) context.getSystemService(
                Context.POWER_SERVICE);
        mWakeLock = powerManager.newWakeLock(PowerManager.PARTIAL_WAKE_LOCK, TAG);

        HandlerThread thread = new HandlerThread(TAG);
        thread.start();
        mHandler = new Handler(thread.getLooper(), mHandlerCallback);

        mSystemDir = checkNotNull(systemDir);
        mBaseDir = new File(systemDir, "netstats");
        mBaseDir.mkdirs();
    }

    public void bindConnectivityManager(IConnectivityManager connManager) {
        mConnManager = checkNotNull(connManager, "missing IConnectivityManager");
    }

    public void systemReady() {
        mSystemReady = true;

        if (!isBandwidthControlEnabled()) {
            Slog.w(TAG, "bandwidth controls disabled, unable to track stats");
            return;
        }

        // create data recorders along with historical rotators
        mDevRecorder = buildRecorder(PREFIX_DEV, mSettings.getDevConfig(), false);
        mXtRecorder = buildRecorder(PREFIX_XT, mSettings.getXtConfig(), false);
        mUidRecorder = buildRecorder(PREFIX_UID, mSettings.getUidConfig(), false);
        mUidTagRecorder = buildRecorder(PREFIX_UID_TAG, mSettings.getUidTagConfig(), true);

        updatePersistThresholds();

        synchronized (mStatsLock) {
            // upgrade any legacy stats, migrating them to rotated files
            maybeUpgradeLegacyStatsLocked();

            // read historical network stats from disk, since policy service
            // might need them right away.
            mDevStatsCached = mDevRecorder.getOrLoadCompleteLocked();
            mXtStatsCached = mXtRecorder.getOrLoadCompleteLocked();

            // bootstrap initial stats to prevent double-counting later
            bootstrapStatsLocked();
        }

        // watch for network interfaces to be claimed
        final IntentFilter connFilter = new IntentFilter(CONNECTIVITY_ACTION_IMMEDIATE);
        mContext.registerReceiver(mConnReceiver, connFilter, CONNECTIVITY_INTERNAL, mHandler);

        // watch for tethering changes
        final IntentFilter tetherFilter = new IntentFilter(ACTION_TETHER_STATE_CHANGED);
        mContext.registerReceiver(mTetherReceiver, tetherFilter, CONNECTIVITY_INTERNAL, mHandler);

        // listen for periodic polling events
        final IntentFilter pollFilter = new IntentFilter(ACTION_NETWORK_STATS_POLL);
        mContext.registerReceiver(mPollReceiver, pollFilter, READ_NETWORK_USAGE_HISTORY, mHandler);

        // listen for uid removal to clean stats
        final IntentFilter removedFilter = new IntentFilter(ACTION_UID_REMOVED);
        mContext.registerReceiver(mRemovedReceiver, removedFilter, null, mHandler);

        // listen for user changes to clean stats
        final IntentFilter userFilter = new IntentFilter(ACTION_USER_REMOVED);
        mContext.registerReceiver(mUserReceiver, userFilter, null, mHandler);

        // persist stats during clean shutdown
        final IntentFilter shutdownFilter = new IntentFilter(ACTION_SHUTDOWN);
        mContext.registerReceiver(mShutdownReceiver, shutdownFilter);

        try {
            mNetworkManager.registerObserver(mAlertObserver);
        } catch (RemoteException e) {
            // ignored; service lives in system_server
        }

        // watch for networkType changes that aren't broadcast through
        // CONNECTIVITY_ACTION_IMMEDIATE above.
        if (!COMBINE_SUBTYPE_ENABLED) {
            mTeleManager.listen(mPhoneListener, LISTEN_DATA_CONNECTION_STATE);
        }

        registerPollAlarmLocked();
        registerGlobalAlert();
    }

    private NetworkStatsRecorder buildRecorder(
            String prefix, NetworkStatsSettings.Config config, boolean includeTags) {
        final DropBoxManager dropBox = (DropBoxManager) mContext.getSystemService(
                Context.DROPBOX_SERVICE);
        return new NetworkStatsRecorder(new FileRotator(
                mBaseDir, prefix, config.rotateAgeMillis, config.deleteAgeMillis),
                mNonMonotonicObserver, dropBox, prefix, config.bucketDuration, includeTags);
    }

    private void shutdownLocked() {
        mContext.unregisterReceiver(mConnReceiver);
        mContext.unregisterReceiver(mTetherReceiver);
        mContext.unregisterReceiver(mPollReceiver);
        mContext.unregisterReceiver(mRemovedReceiver);
        mContext.unregisterReceiver(mShutdownReceiver);

        if (!COMBINE_SUBTYPE_ENABLED) {
            mTeleManager.listen(mPhoneListener, LISTEN_NONE);
        }

        final long currentTime = mTime.hasCache() ? mTime.currentTimeMillis()
                : System.currentTimeMillis();

        // persist any pending stats
        mDevRecorder.forcePersistLocked(currentTime);
        mXtRecorder.forcePersistLocked(currentTime);
        mUidRecorder.forcePersistLocked(currentTime);
        mUidTagRecorder.forcePersistLocked(currentTime);

        mDevRecorder = null;
        mXtRecorder = null;
        mUidRecorder = null;
        mUidTagRecorder = null;

        mDevStatsCached = null;
        mXtStatsCached = null;

        mSystemReady = false;
    }

    private void maybeUpgradeLegacyStatsLocked() {
        File file;
        try {
            file = new File(mSystemDir, "netstats.bin");
            if (file.exists()) {
                mDevRecorder.importLegacyNetworkLocked(file);
                file.delete();
            }

            file = new File(mSystemDir, "netstats_xt.bin");
            if (file.exists()) {
                file.delete();
            }

            file = new File(mSystemDir, "netstats_uid.bin");
            if (file.exists()) {
                mUidRecorder.importLegacyUidLocked(file);
                mUidTagRecorder.importLegacyUidLocked(file);
                file.delete();
            }
        } catch (IOException e) {
            Log.wtf(TAG, "problem during legacy upgrade", e);
        } catch (OutOfMemoryError e) {
            Log.wtf(TAG, "problem during legacy upgrade", e);
        }
    }

    /**
     * Clear any existing {@link #ACTION_NETWORK_STATS_POLL} alarms, and
     * reschedule based on current {@link NetworkStatsSettings#getPollInterval()}.
     */
    private void registerPollAlarmLocked() {
        if (mPollIntent != null) {
            mAlarmManager.cancel(mPollIntent);
        }

        mPollIntent = PendingIntent.getBroadcast(
                mContext, 0, new Intent(ACTION_NETWORK_STATS_POLL), 0);

        final long currentRealtime = SystemClock.elapsedRealtime();
        mAlarmManager.setInexactRepeating(AlarmManager.ELAPSED_REALTIME, currentRealtime,
                mSettings.getPollInterval(), mPollIntent);
    }

    /**
     * Register for a global alert that is delivered through
     * {@link INetworkManagementEventObserver} once a threshold amount of data
     * has been transferred.
     */
    private void registerGlobalAlert() {
        try {
            mNetworkManager.setGlobalAlert(mGlobalAlertBytes);
        } catch (IllegalStateException e) {
            Slog.w(TAG, "problem registering for global alert: " + e);
        } catch (RemoteException e) {
            // ignored; service lives in system_server
        }
    }

    @Override
    public INetworkStatsSession openSession() {
        mContext.enforceCallingOrSelfPermission(READ_NETWORK_USAGE_HISTORY, TAG);
        assertBandwidthControlEnabled();

        // return an IBinder which holds strong references to any loaded stats
        // for its lifetime; when caller closes only weak references remain.

        return new INetworkStatsSession.Stub() {
            private NetworkStatsCollection mUidComplete;
            private NetworkStatsCollection mUidTagComplete;

            private NetworkStatsCollection getUidComplete() {
                if (mUidComplete == null) {
                    synchronized (mStatsLock) {
                        mUidComplete = mUidRecorder.getOrLoadCompleteLocked();
                    }
                }
                return mUidComplete;
            }

            private NetworkStatsCollection getUidTagComplete() {
                if (mUidTagComplete == null) {
                    synchronized (mStatsLock) {
                        mUidTagComplete = mUidTagRecorder.getOrLoadCompleteLocked();
                    }
                }
                return mUidTagComplete;
            }

            @Override
            public NetworkStats getSummaryForNetwork(
                    NetworkTemplate template, long start, long end) {
                return internalGetSummaryForNetwork(template, start, end);
            }

            @Override
            public NetworkStatsHistory getHistoryForNetwork(NetworkTemplate template, int fields) {
                return internalGetHistoryForNetwork(template, fields);
            }

            @Override
            public NetworkStats getSummaryForAllUid(
                    NetworkTemplate template, long start, long end, boolean includeTags) {
                final NetworkStats stats = getUidComplete().getSummary(template, start, end);
                if (includeTags) {
                    final NetworkStats tagStats = getUidTagComplete()
                            .getSummary(template, start, end);
                    stats.combineAllValues(tagStats);
                }
                return stats;
            }

            @Override
            public NetworkStatsHistory getHistoryForUid(
                    NetworkTemplate template, int uid, int set, int tag, int fields) {
                if (tag == TAG_NONE) {
                    return getUidComplete().getHistory(template, uid, set, tag, fields);
                } else {
                    return getUidTagComplete().getHistory(template, uid, set, tag, fields);
                }
            }

            @Override
            public void close() {
                mUidComplete = null;
                mUidTagComplete = null;
            }
        };
    }

    /**
     * Return network summary, splicing between {@link #mDevStatsCached}
     * and {@link #mXtStatsCached} when appropriate.
     */
    private NetworkStats internalGetSummaryForNetwork(
            NetworkTemplate template, long start, long end) {
        if (!mSettings.getReportXtOverDev()) {
            // shortcut when XT reporting disabled
            return mDevStatsCached.getSummary(template, start, end);
        }

        // splice stats between DEV and XT, switching over from DEV to XT at
        // first atomic bucket.
        final long firstAtomicBucket = mXtStatsCached.getFirstAtomicBucketMillis();
        final NetworkStats dev = mDevStatsCached.getSummary(
                template, Math.min(start, firstAtomicBucket), Math.min(end, firstAtomicBucket));
        final NetworkStats xt = mXtStatsCached.getSummary(
                template, Math.max(start, firstAtomicBucket), Math.max(end, firstAtomicBucket));

        xt.combineAllValues(dev);
        return xt;
    }

    /**
     * Return network history, splicing between {@link #mDevStatsCached}
     * and {@link #mXtStatsCached} when appropriate.
     */
    private NetworkStatsHistory internalGetHistoryForNetwork(NetworkTemplate template, int fields) {
        if (!mSettings.getReportXtOverDev()) {
            // shortcut when XT reporting disabled
            return mDevStatsCached.getHistory(template, UID_ALL, SET_ALL, TAG_NONE, fields);
        }

        // splice stats between DEV and XT, switching over from DEV to XT at
        // first atomic bucket.
        final long firstAtomicBucket = mXtStatsCached.getFirstAtomicBucketMillis();
        final NetworkStatsHistory dev = mDevStatsCached.getHistory(
                template, UID_ALL, SET_ALL, TAG_NONE, fields, Long.MIN_VALUE, firstAtomicBucket);
        final NetworkStatsHistory xt = mXtStatsCached.getHistory(
                template, UID_ALL, SET_ALL, TAG_NONE, fields, firstAtomicBucket, Long.MAX_VALUE);

        xt.recordEntireHistory(dev);
        return xt;
    }

    @Override
    public long getNetworkTotalBytes(NetworkTemplate template, long start, long end) {
        mContext.enforceCallingOrSelfPermission(READ_NETWORK_USAGE_HISTORY, TAG);
        assertBandwidthControlEnabled();
        return internalGetSummaryForNetwork(template, start, end).getTotalBytes();
    }

    @Override
    public NetworkStats getDataLayerSnapshotForUid(int uid) throws RemoteException {
        if (Binder.getCallingUid() != uid) {
            mContext.enforceCallingOrSelfPermission(ACCESS_NETWORK_STATE, TAG);
        }
        assertBandwidthControlEnabled();

        // TODO: switch to data layer stats once kernel exports
        // for now, read network layer stats and flatten across all ifaces
        final long token = Binder.clearCallingIdentity();
        final NetworkStats networkLayer;
        try {
            networkLayer = mNetworkManager.getNetworkStatsUidDetail(uid);
        } finally {
            Binder.restoreCallingIdentity(token);
        }

        // splice in operation counts
        networkLayer.spliceOperationsFrom(mUidOperations);

        final NetworkStats dataLayer = new NetworkStats(
                networkLayer.getElapsedRealtime(), networkLayer.size());

        NetworkStats.Entry entry = null;
        for (int i = 0; i < networkLayer.size(); i++) {
            entry = networkLayer.getValues(i, entry);
            entry.iface = IFACE_ALL;
            dataLayer.combineValues(entry);
        }

        return dataLayer;
    }

    @Override
    public String[] getMobileIfaces() {
        return mMobileIfaces;
    }

    @Override
    public void incrementOperationCount(int uid, int tag, int operationCount) {
        if (Binder.getCallingUid() != uid) {
            mContext.enforceCallingOrSelfPermission(MODIFY_NETWORK_ACCOUNTING, TAG);
        }

        if (operationCount < 0) {
            throw new IllegalArgumentException("operation count can only be incremented");
        }
        if (tag == TAG_NONE) {
            throw new IllegalArgumentException("operation count must have specific tag");
        }

        synchronized (mStatsLock) {
            final int set = mActiveUidCounterSet.get(uid, SET_DEFAULT);
            mUidOperations.combineValues(
                    mActiveIface, uid, set, tag, 0L, 0L, 0L, 0L, operationCount);
            mUidOperations.combineValues(
                    mActiveIface, uid, set, TAG_NONE, 0L, 0L, 0L, 0L, operationCount);
        }
    }

    @Override
    public void setUidForeground(int uid, boolean uidForeground) {
        mContext.enforceCallingOrSelfPermission(MODIFY_NETWORK_ACCOUNTING, TAG);

        synchronized (mStatsLock) {
            final int set = uidForeground ? SET_FOREGROUND : SET_DEFAULT;
            final int oldSet = mActiveUidCounterSet.get(uid, SET_DEFAULT);
            if (oldSet != set) {
                mActiveUidCounterSet.put(uid, set);
                setKernelCounterSet(uid, set);
            }
        }
    }

    @Override
    public void forceUpdate() {
        mContext.enforceCallingOrSelfPermission(READ_NETWORK_USAGE_HISTORY, TAG);
        assertBandwidthControlEnabled();

        final long token = Binder.clearCallingIdentity();
        try {
            performPoll(FLAG_PERSIST_ALL);
        } finally {
            Binder.restoreCallingIdentity(token);
        }
    }

    @Override
    public void advisePersistThreshold(long thresholdBytes) {
        mContext.enforceCallingOrSelfPermission(MODIFY_NETWORK_ACCOUNTING, TAG);
        assertBandwidthControlEnabled();

        // clamp threshold into safe range
        mPersistThreshold = MathUtils.constrain(thresholdBytes, 128 * KB_IN_BYTES, 2 * MB_IN_BYTES);
        if (LOGV) {
            Slog.v(TAG, "advisePersistThreshold() given " + thresholdBytes + ", clamped to "
                    + mPersistThreshold);
        }

        // update and persist if beyond new thresholds
        final long currentTime = mTime.hasCache() ? mTime.currentTimeMillis()
                : System.currentTimeMillis();
        synchronized (mStatsLock) {
            if (!mSystemReady) return;

            updatePersistThresholds();

            mDevRecorder.maybePersistLocked(currentTime);
            mXtRecorder.maybePersistLocked(currentTime);
            mUidRecorder.maybePersistLocked(currentTime);
            mUidTagRecorder.maybePersistLocked(currentTime);
        }

        // re-arm global alert
        registerGlobalAlert();
    }

    /**
     * Update {@link NetworkStatsRecorder} and {@link #mGlobalAlertBytes} to
     * reflect current {@link #mPersistThreshold} value. Always defers to
     * {@link Global} values when defined.
     */
    private void updatePersistThresholds() {
        mDevRecorder.setPersistThreshold(mSettings.getDevPersistBytes(mPersistThreshold));
        mXtRecorder.setPersistThreshold(mSettings.getXtPersistBytes(mPersistThreshold));
        mUidRecorder.setPersistThreshold(mSettings.getUidPersistBytes(mPersistThreshold));
        mUidTagRecorder.setPersistThreshold(mSettings.getUidTagPersistBytes(mPersistThreshold));
        mGlobalAlertBytes = mSettings.getGlobalAlertBytes(mPersistThreshold);
    }

    /**
     * Receiver that watches for {@link IConnectivityManager} to claim network
     * interfaces. Used to associate {@link TelephonyManager#getSubscriberId()}
     * with mobile interfaces.
     */
    private BroadcastReceiver mConnReceiver = new BroadcastReceiver() {
        @Override
        public void onReceive(Context context, Intent intent) {
            // on background handler thread, and verified CONNECTIVITY_INTERNAL
            // permission above.
            updateIfaces();
        }
    };

    /**
     * Receiver that watches for {@link Tethering} to claim interface pairs.
     */
    private BroadcastReceiver mTetherReceiver = new BroadcastReceiver() {
        @Override
        public void onReceive(Context context, Intent intent) {
            // on background handler thread, and verified CONNECTIVITY_INTERNAL
            // permission above.
            performPoll(FLAG_PERSIST_NETWORK);
        }
    };

    private BroadcastReceiver mPollReceiver = new BroadcastReceiver() {
        @Override
        public void onReceive(Context context, Intent intent) {
            // on background handler thread, and verified UPDATE_DEVICE_STATS
            // permission above.
            performPoll(FLAG_PERSIST_ALL);

            // verify that we're watching global alert
            registerGlobalAlert();
        }
    };

    private BroadcastReceiver mRemovedReceiver = new BroadcastReceiver() {
        @Override
        public void onReceive(Context context, Intent intent) {
            // on background handler thread, and UID_REMOVED is protected
            // broadcast.

            final int uid = intent.getIntExtra(EXTRA_UID, -1);
            if (uid == -1) return;

            synchronized (mStatsLock) {
                mWakeLock.acquire();
                try {
                    removeUidsLocked(uid);
                } finally {
                    mWakeLock.release();
                }
            }
        }
    };

    private BroadcastReceiver mUserReceiver = new BroadcastReceiver() {
        @Override
        public void onReceive(Context context, Intent intent) {
            // On background handler thread, and USER_REMOVED is protected
            // broadcast.

            final int userId = intent.getIntExtra(Intent.EXTRA_USER_HANDLE, -1);
            if (userId == -1) return;

            synchronized (mStatsLock) {
                mWakeLock.acquire();
                try {
                    removeUserLocked(userId);
                } finally {
                    mWakeLock.release();
                }
            }
        }
    };

    private BroadcastReceiver mShutdownReceiver = new BroadcastReceiver() {
        @Override
        public void onReceive(Context context, Intent intent) {
            // SHUTDOWN is protected broadcast.
            synchronized (mStatsLock) {
                shutdownLocked();
            }
        }
    };

    /**
     * Observer that watches for {@link INetworkManagementService} alerts.
     */
    private INetworkManagementEventObserver mAlertObserver = new BaseNetworkObserver() {
        @Override
        public void limitReached(String limitName, String iface) {
            // only someone like NMS should be calling us
            mContext.enforceCallingOrSelfPermission(CONNECTIVITY_INTERNAL, TAG);

            if (LIMIT_GLOBAL_ALERT.equals(limitName)) {
                // kick off background poll to collect network stats; UID stats
                // are handled during normal polling interval.
                final int flags = FLAG_PERSIST_NETWORK;
                mHandler.obtainMessage(MSG_PERFORM_POLL, flags, 0).sendToTarget();

                // re-arm global alert for next update
                mHandler.obtainMessage(MSG_REGISTER_GLOBAL_ALERT).sendToTarget();
            }
        }
    };

    private int mLastPhoneState = TelephonyManager.DATA_UNKNOWN;
    private int mLastPhoneNetworkType = TelephonyManager.NETWORK_TYPE_UNKNOWN;

    /**
     * Receiver that watches for {@link TelephonyManager} changes, such as
     * transitioning between network types.
     */
    private PhoneStateListener mPhoneListener = new PhoneStateListener() {
        @Override
        public void onDataConnectionStateChanged(int state, int networkType) {
            final boolean stateChanged = state != mLastPhoneState;
            final boolean networkTypeChanged = networkType != mLastPhoneNetworkType;

            if (networkTypeChanged && !stateChanged) {
                // networkType changed without a state change, which means we
                // need to roll our own update. delay long enough for
                // ConnectivityManager to process.
                // TODO: add direct event to ConnectivityService instead of
                // relying on this delay.
                if (LOGV) Slog.v(TAG, "triggering delayed updateIfaces()");
                mHandler.sendMessageDelayed(
                        mHandler.obtainMessage(MSG_UPDATE_IFACES), SECOND_IN_MILLIS);
            }

            mLastPhoneState = state;
            mLastPhoneNetworkType = networkType;
        }
    };

    private void updateIfaces() {
        synchronized (mStatsLock) {
            mWakeLock.acquire();
            try {
                updateIfacesLocked();
            } finally {
                mWakeLock.release();
            }
        }
    }

    /**
     * Inspect all current {@link NetworkState} to derive mapping from {@code
     * iface} to {@link NetworkStatsHistory}. When multiple {@link NetworkInfo}
     * are active on a single {@code iface}, they are combined under a single
     * {@link NetworkIdentitySet}.
     */
    private void updateIfacesLocked() {
        if (!mSystemReady) return;
        if (LOGV) Slog.v(TAG, "updateIfacesLocked()");

        // take one last stats snapshot before updating iface mapping. this
        // isn't perfect, since the kernel may already be counting traffic from
        // the updated network.

        // poll, but only persist network stats to keep codepath fast. UID stats
        // will be persisted during next alarm poll event.
        performPollLocked(FLAG_PERSIST_NETWORK);

        final NetworkState[] states;
        final LinkProperties activeLink;
        try {
            states = mConnManager.getAllNetworkState();
            activeLink = mConnManager.getActiveLinkProperties();
        } catch (RemoteException e) {
            // ignored; service lives in system_server
            return;
        }

        mActiveIface = activeLink != null ? activeLink.getInterfaceName() : null;

        // rebuild active interfaces based on connected networks
        mActiveIfaces.clear();

        for (NetworkState state : states) {
            if (state.networkInfo.isConnected()) {
                // collect networks under their parent interfaces
                final String iface = state.linkProperties.getInterfaceName();

                NetworkIdentitySet ident = mActiveIfaces.get(iface);
                if (ident == null) {
                    ident = new NetworkIdentitySet();
                    mActiveIfaces.put(iface, ident);
                }

                ident.add(NetworkIdentity.buildNetworkIdentity(mContext, state));

                // remember any ifaces associated with mobile networks
                if (isNetworkTypeMobile(state.networkInfo.getType()) && iface != null) {
                    if (!contains(mMobileIfaces, iface)) {
                        mMobileIfaces = appendElement(String.class, mMobileIfaces, iface);
                    }
                }
            }
        }
    }

    /**
     * Bootstrap initial stats snapshot, usually during {@link #systemReady()}
     * so we have baseline values without double-counting.
     */
    private void bootstrapStatsLocked() {
        final long currentTime = mTime.hasCache() ? mTime.currentTimeMillis()
                : System.currentTimeMillis();

        try {
            // snapshot and record current counters; read UID stats first to
            // avoid overcounting dev stats.
            final NetworkStats uidSnapshot = getNetworkStatsUidDetail();
            final NetworkStats xtSnapshot = mNetworkManager.getNetworkStatsSummaryXt();
            final NetworkStats devSnapshot = mNetworkManager.getNetworkStatsSummaryDev();

            mDevRecorder.recordSnapshotLocked(devSnapshot, mActiveIfaces, currentTime);
            mXtRecorder.recordSnapshotLocked(xtSnapshot, mActiveIfaces, currentTime);
            mUidRecorder.recordSnapshotLocked(uidSnapshot, mActiveIfaces, currentTime);
            mUidTagRecorder.recordSnapshotLocked(uidSnapshot, mActiveIfaces, currentTime);

        } catch (IllegalStateException e) {
            Slog.w(TAG, "problem reading network stats: " + e);
        } catch (RemoteException e) {
            // ignored; service lives in system_server
        }
    }

    private void performPoll(int flags) {
        // try refreshing time source when stale
        if (mTime.getCacheAge() > mSettings.getTimeCacheMaxAge()) {
            mTime.forceRefresh();
        }

        synchronized (mStatsLock) {
            mWakeLock.acquire();

            try {
                performPollLocked(flags);
            } finally {
                mWakeLock.release();
            }
        }
    }

    /**
     * Periodic poll operation, reading current statistics and recording into
     * {@link NetworkStatsHistory}.
     */
    private void performPollLocked(int flags) {
        if (!mSystemReady) return;
        if (LOGV) Slog.v(TAG, "performPollLocked(flags=0x" + Integer.toHexString(flags) + ")");

        final long startRealtime = SystemClock.elapsedRealtime();

        final boolean persistNetwork = (flags & FLAG_PERSIST_NETWORK) != 0;
        final boolean persistUid = (flags & FLAG_PERSIST_UID) != 0;
        final boolean persistForce = (flags & FLAG_PERSIST_FORCE) != 0;

        // TODO: consider marking "untrusted" times in historical stats
        final long currentTime = mTime.hasCache() ? mTime.currentTimeMillis()
                : System.currentTimeMillis();

        try {
            // snapshot and record current counters; read UID stats first to
            // avoid overcounting dev stats.
            final NetworkStats uidSnapshot = getNetworkStatsUidDetail();
            final NetworkStats xtSnapshot = mNetworkManager.getNetworkStatsSummaryXt();
            final NetworkStats devSnapshot = mNetworkManager.getNetworkStatsSummaryDev();

            mDevRecorder.recordSnapshotLocked(devSnapshot, mActiveIfaces, currentTime);
            mXtRecorder.recordSnapshotLocked(xtSnapshot, mActiveIfaces, currentTime);
            mUidRecorder.recordSnapshotLocked(uidSnapshot, mActiveIfaces, currentTime);
            mUidTagRecorder.recordSnapshotLocked(uidSnapshot, mActiveIfaces, currentTime);

        } catch (IllegalStateException e) {
            Log.wtf(TAG, "problem reading network stats", e);
            return;
        } catch (RemoteException e) {
            // ignored; service lives in system_server
            return;
        }

        // persist any pending data depending on requested flags
        if (persistForce) {
            mDevRecorder.forcePersistLocked(currentTime);
            mXtRecorder.forcePersistLocked(currentTime);
            mUidRecorder.forcePersistLocked(currentTime);
            mUidTagRecorder.forcePersistLocked(currentTime);
        } else {
            if (persistNetwork) {
                mDevRecorder.maybePersistLocked(currentTime);
                mXtRecorder.maybePersistLocked(currentTime);
            }
            if (persistUid) {
                mUidRecorder.maybePersistLocked(currentTime);
                mUidTagRecorder.maybePersistLocked(currentTime);
            }
        }

        if (LOGV) {
            final long duration = SystemClock.elapsedRealtime() - startRealtime;
            Slog.v(TAG, "performPollLocked() took " + duration + "ms");
        }

        if (mSettings.getSampleEnabled()) {
            // sample stats after each full poll
            performSampleLocked();
        }

        // finally, dispatch updated event to any listeners
        final Intent updatedIntent = new Intent(ACTION_NETWORK_STATS_UPDATED);
        updatedIntent.setFlags(Intent.FLAG_RECEIVER_REGISTERED_ONLY);
        mContext.sendBroadcastAsUser(updatedIntent, UserHandle.ALL,
                READ_NETWORK_USAGE_HISTORY);
    }

    /**
     * Sample recent statistics summary into {@link EventLog}.
     */
    private void performSampleLocked() {
        // TODO: migrate trustedtime fixes to separate binary log events
        final long trustedTime = mTime.hasCache() ? mTime.currentTimeMillis() : -1;

        NetworkTemplate template;
        NetworkStats.Entry devTotal;
        NetworkStats.Entry xtTotal;
        NetworkStats.Entry uidTotal;

        // collect mobile sample
        template = buildTemplateMobileWildcard();
        devTotal = mDevRecorder.getTotalSinceBootLocked(template);
        xtTotal = mXtRecorder.getTotalSinceBootLocked(template);
        uidTotal = mUidRecorder.getTotalSinceBootLocked(template);

        EventLogTags.writeNetstatsMobileSample(
                devTotal.rxBytes, devTotal.rxPackets, devTotal.txBytes, devTotal.txPackets,
                xtTotal.rxBytes, xtTotal.rxPackets, xtTotal.txBytes, xtTotal.txPackets,
                uidTotal.rxBytes, uidTotal.rxPackets, uidTotal.txBytes, uidTotal.txPackets,
                trustedTime);

        // collect wifi sample
        template = buildTemplateWifiWildcard();
        devTotal = mDevRecorder.getTotalSinceBootLocked(template);
        xtTotal = mXtRecorder.getTotalSinceBootLocked(template);
        uidTotal = mUidRecorder.getTotalSinceBootLocked(template);

        EventLogTags.writeNetstatsWifiSample(
                devTotal.rxBytes, devTotal.rxPackets, devTotal.txBytes, devTotal.txPackets,
                xtTotal.rxBytes, xtTotal.rxPackets, xtTotal.txBytes, xtTotal.txPackets,
                uidTotal.rxBytes, uidTotal.rxPackets, uidTotal.txBytes, uidTotal.txPackets,
                trustedTime);
    }

    /**
     * Clean up {@link #mUidRecorder} after UID is removed.
     */
    private void removeUidsLocked(int... uids) {
        if (LOGV) Slog.v(TAG, "removeUidsLocked() for UIDs " + Arrays.toString(uids));

        // Perform one last poll before removing
        performPollLocked(FLAG_PERSIST_ALL);

        mUidRecorder.removeUidsLocked(uids);
        mUidTagRecorder.removeUidsLocked(uids);

        // Clear kernel stats associated with UID
        for (int uid : uids) {
            resetKernelUidStats(uid);
        }
    }

    /**
     * Clean up {@link #mUidRecorder} after user is removed.
     */
    private void removeUserLocked(int userId) {
        if (LOGV) Slog.v(TAG, "removeUserLocked() for userId=" + userId);

        // Build list of UIDs that we should clean up
        int[] uids = new int[0];
        final List<ApplicationInfo> apps = mContext.getPackageManager().getInstalledApplications(
                PackageManager.GET_UNINSTALLED_PACKAGES | PackageManager.GET_DISABLED_COMPONENTS);
        for (ApplicationInfo app : apps) {
            final int uid = UserHandle.getUid(userId, app.uid);
            uids = ArrayUtils.appendInt(uids, uid);
        }

        removeUidsLocked(uids);
    }

    @Override
    protected void dump(FileDescriptor fd, PrintWriter writer, String[] args) {
        mContext.enforceCallingOrSelfPermission(DUMP, TAG);

        final HashSet<String> argSet = new HashSet<String>();
        for (String arg : args) {
            argSet.add(arg);
        }

        // usage: dumpsys netstats --full --uid --tag --poll --checkin
        final boolean poll = argSet.contains("--poll") || argSet.contains("poll");
        final boolean checkin = argSet.contains("--checkin");
        final boolean fullHistory = argSet.contains("--full") || argSet.contains("full");
        final boolean includeUid = argSet.contains("--uid") || argSet.contains("detail");
        final boolean includeTag = argSet.contains("--tag") || argSet.contains("detail");

        final IndentingPrintWriter pw = new IndentingPrintWriter(writer, "  ");

        synchronized (mStatsLock) {
            if (poll) {
                performPollLocked(FLAG_PERSIST_ALL | FLAG_PERSIST_FORCE);
                pw.println("Forced poll");
                return;
            }

            if (checkin) {
                // list current stats files to verify rotation
                pw.println("Current files:");
                pw.increaseIndent();
                for (String file : mBaseDir.list()) {
                    pw.println(file);
                }
                pw.decreaseIndent();
                return;
            }

            pw.println("Active interfaces:");
            pw.increaseIndent();
            for (String iface : mActiveIfaces.keySet()) {
                final NetworkIdentitySet ident = mActiveIfaces.get(iface);
                pw.print("iface="); pw.print(iface);
                pw.print(" ident="); pw.println(ident.toString());
            }
            pw.decreaseIndent();

            pw.println("Dev stats:");
            pw.increaseIndent();
            mDevRecorder.dumpLocked(pw, fullHistory);
            pw.decreaseIndent();

            pw.println("Xt stats:");
            pw.increaseIndent();
            mXtRecorder.dumpLocked(pw, fullHistory);
            pw.decreaseIndent();

            if (includeUid) {
                pw.println("UID stats:");
                pw.increaseIndent();
                mUidRecorder.dumpLocked(pw, fullHistory);
                pw.decreaseIndent();
            }

            if (includeTag) {
                pw.println("UID tag stats:");
                pw.increaseIndent();
                mUidTagRecorder.dumpLocked(pw, fullHistory);
                pw.decreaseIndent();
            }
        }
    }

    /**
     * Return snapshot of current UID statistics, including any
     * {@link TrafficStats#UID_TETHERING} and {@link #mUidOperations} values.
     */
    private NetworkStats getNetworkStatsUidDetail() throws RemoteException {
        final NetworkStats uidSnapshot = mNetworkManager.getNetworkStatsUidDetail(UID_ALL);

        // fold tethering stats and operations into uid snapshot
        final NetworkStats tetherSnapshot = getNetworkStatsTethering();
        uidSnapshot.combineAllValues(tetherSnapshot);
        uidSnapshot.combineAllValues(mUidOperations);

        return uidSnapshot;
    }

    /**
     * Return snapshot of current tethering statistics. Will return empty
     * {@link NetworkStats} if any problems are encountered.
     */
    private NetworkStats getNetworkStatsTethering() throws RemoteException {
        try {
            return mNetworkManager.getNetworkStatsTethering();
        } catch (IllegalStateException e) {
            Log.wtf(TAG, "problem reading network stats", e);
            return new NetworkStats(0L, 10);
        }
    }

    private Handler.Callback mHandlerCallback = new Handler.Callback() {
        @Override
        public boolean handleMessage(Message msg) {
            switch (msg.what) {
                case MSG_PERFORM_POLL: {
                    final int flags = msg.arg1;
                    performPoll(flags);
                    return true;
                }
                case MSG_UPDATE_IFACES: {
                    updateIfaces();
                    return true;
                }
                case MSG_REGISTER_GLOBAL_ALERT: {
                    registerGlobalAlert();
                    return true;
                }
                default: {
                    return false;
                }
            }
        }
    };

    private void assertBandwidthControlEnabled() {
        if (!isBandwidthControlEnabled()) {
            throw new IllegalStateException("Bandwidth module disabled");
        }
    }

    private boolean isBandwidthControlEnabled() {
        final long token = Binder.clearCallingIdentity();
        try {
            return mNetworkManager.isBandwidthControlEnabled();
        } catch (RemoteException e) {
            // ignored; service lives in system_server
            return false;
        } finally {
            Binder.restoreCallingIdentity(token);
        }
    }

    private class DropBoxNonMonotonicObserver implements NonMonotonicObserver<String> {
        @Override
        public void foundNonMonotonic(NetworkStats left, int leftIndex, NetworkStats right,
                int rightIndex, String cookie) {
            Log.w(TAG, "found non-monotonic values; saving to dropbox");

            // record error for debugging
            final StringBuilder builder = new StringBuilder();
            builder.append("found non-monotonic " + cookie + " values at left[" + leftIndex
                    + "] - right[" + rightIndex + "]\n");
            builder.append("left=").append(left).append('\n');
            builder.append("right=").append(right).append('\n');

            final DropBoxManager dropBox = (DropBoxManager) mContext.getSystemService(
                    Context.DROPBOX_SERVICE);
            dropBox.addText(TAG_NETSTATS_ERROR, builder.toString());
        }
    }

    /**
     * Default external settings that read from
     * {@link android.provider.Settings.Global}.
     */
    private static class DefaultNetworkStatsSettings implements NetworkStatsSettings {
        private final ContentResolver mResolver;

        public DefaultNetworkStatsSettings(Context context) {
            mResolver = checkNotNull(context.getContentResolver());
            // TODO: adjust these timings for production builds
        }

        private long getGlobalLong(String name, long def) {
            return Settings.Global.getLong(mResolver, name, def);
        }
        private boolean getGlobalBoolean(String name, boolean def) {
            final int defInt = def ? 1 : 0;
            return Settings.Global.getInt(mResolver, name, defInt) != 0;
        }

        @Override
        public long getPollInterval() {
            return getGlobalLong(NETSTATS_POLL_INTERVAL, 30 * MINUTE_IN_MILLIS);
        }
        @Override
        public long getTimeCacheMaxAge() {
            return getGlobalLong(NETSTATS_TIME_CACHE_MAX_AGE, DAY_IN_MILLIS);
        }
        @Override
        public long getGlobalAlertBytes(long def) {
            return getGlobalLong(NETSTATS_GLOBAL_ALERT_BYTES, def);
        }
        @Override
        public boolean getSampleEnabled() {
            return getGlobalBoolean(NETSTATS_SAMPLE_ENABLED, true);
        }
        @Override
        public boolean getReportXtOverDev() {
            return getGlobalBoolean(NETSTATS_REPORT_XT_OVER_DEV, true);
        }
        @Override
        public Config getDevConfig() {
            return new Config(getGlobalLong(NETSTATS_DEV_BUCKET_DURATION, HOUR_IN_MILLIS),
                    getGlobalLong(NETSTATS_DEV_ROTATE_AGE, 15 * DAY_IN_MILLIS),
                    getGlobalLong(NETSTATS_DEV_DELETE_AGE, 90 * DAY_IN_MILLIS));
        }
        @Override
        public Config getXtConfig() {
            return getDevConfig();
        }
        @Override
        public Config getUidConfig() {
            return new Config(getGlobalLong(NETSTATS_UID_BUCKET_DURATION, 2 * HOUR_IN_MILLIS),
                    getGlobalLong(NETSTATS_UID_ROTATE_AGE, 15 * DAY_IN_MILLIS),
                    getGlobalLong(NETSTATS_UID_DELETE_AGE, 90 * DAY_IN_MILLIS));
        }
        @Override
        public Config getUidTagConfig() {
            return new Config(getGlobalLong(NETSTATS_UID_TAG_BUCKET_DURATION, 2 * HOUR_IN_MILLIS),
                    getGlobalLong(NETSTATS_UID_TAG_ROTATE_AGE, 5 * DAY_IN_MILLIS),
                    getGlobalLong(NETSTATS_UID_TAG_DELETE_AGE, 15 * DAY_IN_MILLIS));
        }
        @Override
        public long getDevPersistBytes(long def) {
            return getGlobalLong(NETSTATS_DEV_PERSIST_BYTES, def);
        }
        @Override
        public long getXtPersistBytes(long def) {
            return getDevPersistBytes(def);
        }
        @Override
        public long getUidPersistBytes(long def) {
            return getGlobalLong(NETSTATS_UID_PERSIST_BYTES, def);
        }
        @Override
        public long getUidTagPersistBytes(long def) {
            return getGlobalLong(NETSTATS_UID_TAG_PERSIST_BYTES, def);
        }
    }
}