1 /*
2  * Copyright (C) 2009 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 
17 package com.android.server;
18 
19 import android.annotation.Nullable;
20 import android.app.ActivityManager;
21 import android.app.AppOpsManager;
22 import android.app.BroadcastOptions;
23 import android.content.BroadcastReceiver;
24 import android.content.ContentResolver;
25 import android.content.Context;
26 import android.content.Intent;
27 import android.content.IntentFilter;
28 import android.content.pm.PackageManager;
29 import android.content.res.Resources;
30 import android.database.ContentObserver;
31 import android.net.Uri;
32 import android.os.Binder;
33 import android.os.Bundle;
34 import android.os.BundleMerger;
35 import android.os.Debug;
36 import android.os.DropBoxManager;
37 import android.os.FileUtils;
38 import android.os.Handler;
39 import android.os.Looper;
40 import android.os.Message;
41 import android.os.ParcelFileDescriptor;
42 import android.os.ResultReceiver;
43 import android.os.ShellCallback;
44 import android.os.ShellCommand;
45 import android.os.StatFs;
46 import android.os.SystemClock;
47 import android.os.UserHandle;
48 import android.provider.Settings;
49 import android.service.dropbox.DropBoxManagerServiceDumpProto;
50 import android.system.ErrnoException;
51 import android.system.Os;
52 import android.system.OsConstants;
53 import android.system.StructStat;
54 import android.text.TextUtils;
55 import android.text.format.TimeMigrationUtils;
56 import android.util.ArrayMap;
57 import android.util.ArraySet;
58 import android.util.Slog;
59 import android.util.proto.ProtoOutputStream;
60 
61 import com.android.internal.R;
62 import com.android.internal.annotations.GuardedBy;
63 import com.android.internal.annotations.VisibleForTesting;
64 import com.android.internal.os.IDropBoxManagerService;
65 import com.android.internal.util.DumpUtils;
66 import com.android.internal.util.FrameworkStatsLog;
67 import com.android.internal.util.ObjectUtils;
68 import com.android.server.DropBoxManagerInternal.EntrySource;
69 
70 import libcore.io.IoUtils;
71 
72 import java.io.ByteArrayInputStream;
73 import java.io.File;
74 import java.io.FileDescriptor;
75 import java.io.FileOutputStream;
76 import java.io.IOException;
77 import java.io.InputStream;
78 import java.io.InputStreamReader;
79 import java.io.PrintWriter;
80 import java.util.ArrayList;
81 import java.util.Arrays;
82 import java.util.List;
83 import java.util.SortedSet;
84 import java.util.TreeSet;
85 import java.util.zip.GZIPOutputStream;
86 
87 /**
88  * Implementation of {@link IDropBoxManagerService} using the filesystem.
89  * Clients use {@link DropBoxManager} to access this service.
90  */
91 public final class DropBoxManagerService extends SystemService {
92     private static final String TAG = "DropBoxManagerService";
93     private static final int DEFAULT_AGE_SECONDS = 3 * 86400;
94     private static final int DEFAULT_MAX_FILES = 1000;
95     private static final int DEFAULT_MAX_FILES_LOWRAM = 300;
96     private static final int DEFAULT_QUOTA_KB = 10 * 1024;
97     private static final int DEFAULT_QUOTA_PERCENT = 10;
98     private static final int DEFAULT_RESERVE_PERCENT = 0;
99     private static final int QUOTA_RESCAN_MILLIS = 5000;
100 
101     private static final boolean PROFILE_DUMP = false;
102 
103     // Max number of bytes of a dropbox entry to write into protobuf.
104     private static final int PROTO_MAX_DATA_BYTES = 256 * 1024;
105 
106     // Size beyond which to force-compress newly added entries.
107     private static final long COMPRESS_THRESHOLD_BYTES = 16_384;
108 
109     // Tags that we should drop by default.
110     private static final List<String> DISABLED_BY_DEFAULT_TAGS =
111             List.of("data_app_wtf", "system_app_wtf", "system_server_wtf");
112 
113     // TODO: This implementation currently uses one file per entry, which is
114     // inefficient for smallish entries -- consider using a single queue file
115     // per tag (or even globally) instead.
116 
117     // The cached context and derived objects
118 
119     private final ContentResolver mContentResolver;
120     private final File mDropBoxDir;
121 
122     // Accounting of all currently written log files (set in init()).
123 
124     private FileList mAllFiles = null;
125     private ArrayMap<String, FileList> mFilesByTag = null;
126 
127     private long mLowPriorityRateLimitPeriod = 0;
128     private ArraySet<String> mLowPriorityTags = null;
129 
130     // Various bits of disk information
131 
132     private StatFs mStatFs = null;
133     private int mBlockSize = 0;
134     private int mCachedQuotaBlocks = 0;  // Space we can use: computed from free space, etc.
135     private long mCachedQuotaUptimeMillis = 0;
136 
137     private volatile boolean mBooted = false;
138 
139     // Provide a way to perform sendBroadcast asynchronously to avoid deadlocks.
140     private final DropBoxManagerBroadcastHandler mHandler;
141 
142     private int mMaxFiles = -1; // -1 means uninitialized.
143 
144     /** Receives events that might indicate a need to clean up files. */
145     private final BroadcastReceiver mReceiver = new BroadcastReceiver() {
146         @Override
147         public void onReceive(Context context, Intent intent) {
148             // For ACTION_DEVICE_STORAGE_LOW:
149             mCachedQuotaUptimeMillis = 0;  // Force a re-check of quota size
150 
151             // Run the initialization in the background (not this main thread).
152             // The init() and trimToFit() methods are synchronized, so they still
153             // block other users -- but at least the onReceive() call can finish.
154             new Thread() {
155                 public void run() {
156                     try {
157                         init();
158                         trimToFit();
159                     } catch (IOException e) {
160                         Slog.e(TAG, "Can't init", e);
161                     }
162                 }
163             }.start();
164         }
165     };
166 
167     private final IDropBoxManagerService.Stub mStub = new IDropBoxManagerService.Stub() {
168         @Override
169         public void addData(String tag, byte[] data, int flags) {
170             DropBoxManagerService.this.addData(tag, data, flags);
171         }
172 
173         @Override
174         public void addFile(String tag, ParcelFileDescriptor fd, int flags) {
175             DropBoxManagerService.this.addFile(tag, fd, flags);
176         }
177 
178         @Override
179         public boolean isTagEnabled(String tag) {
180             return DropBoxManagerService.this.isTagEnabled(tag);
181         }
182 
183         @Override
184         public DropBoxManager.Entry getNextEntry(String tag, long millis, String callingPackage) {
185             return getNextEntryWithAttribution(tag, millis, callingPackage, null);
186         }
187 
188         @Override
189         public DropBoxManager.Entry getNextEntryWithAttribution(String tag, long millis,
190                 String callingPackage, String callingAttributionTag) {
191             return DropBoxManagerService.this.getNextEntry(tag, millis, callingPackage,
192                     callingAttributionTag);
193         }
194 
195         @Override
196         public void dump(FileDescriptor fd, PrintWriter pw, String[] args) {
197             DropBoxManagerService.this.dump(fd, pw, args);
198         }
199 
200         @Override
201         public void onShellCommand(FileDescriptor in, FileDescriptor out,
202                                    FileDescriptor err, String[] args, ShellCallback callback,
203                                    ResultReceiver resultReceiver) {
204             (new ShellCmd()).exec(this, in, out, err, args, callback, resultReceiver);
205         }
206     };
207 
208     private class ShellCmd extends ShellCommand {
209         @Override
onCommand(String cmd)210         public int onCommand(String cmd) {
211             if (cmd == null) {
212                 return handleDefaultCommands(cmd);
213             }
214             final PrintWriter pw = getOutPrintWriter();
215             try {
216                 switch (cmd) {
217                     case "set-rate-limit":
218                         final long period = Long.parseLong(getNextArgRequired());
219                         DropBoxManagerService.this.setLowPriorityRateLimit(period);
220                         break;
221                     case "add-low-priority":
222                         final String addedTag = getNextArgRequired();
223                         DropBoxManagerService.this.addLowPriorityTag(addedTag);
224                         break;
225                     case "remove-low-priority":
226                         final String removeTag = getNextArgRequired();
227                         DropBoxManagerService.this.removeLowPriorityTag(removeTag);
228                         break;
229                     case "restore-defaults":
230                         DropBoxManagerService.this.restoreDefaults();
231                         break;
232                     default:
233                         return handleDefaultCommands(cmd);
234                 }
235             } catch (Exception e) {
236                 pw.println(e);
237             }
238             return 0;
239         }
240 
241         @Override
onHelp()242         public void onHelp() {
243             PrintWriter pw = getOutPrintWriter();
244             pw.println("Dropbox manager service commands:");
245             pw.println("  help");
246             pw.println("    Print this help text.");
247             pw.println("  set-rate-limit PERIOD");
248             pw.println("    Sets low priority broadcast rate limit period to PERIOD ms");
249             pw.println("  add-low-priority TAG");
250             pw.println("    Add TAG to dropbox low priority list");
251             pw.println("  remove-low-priority TAG");
252             pw.println("    Remove TAG from dropbox low priority list");
253             pw.println("  restore-defaults");
254             pw.println("    restore dropbox settings to defaults");
255         }
256     }
257 
258     private class DropBoxManagerBroadcastHandler extends Handler {
259         private final Object mLock = new Object();
260 
261         static final int MSG_SEND_BROADCAST = 1;
262         static final int MSG_SEND_DEFERRED_BROADCAST = 2;
263 
264         @GuardedBy("mLock")
265         private final ArrayMap<String, Intent> mDeferredMap = new ArrayMap();
266 
DropBoxManagerBroadcastHandler(Looper looper)267         DropBoxManagerBroadcastHandler(Looper looper) {
268             super(looper);
269         }
270 
271         @Override
handleMessage(Message msg)272         public void handleMessage(Message msg) {
273             switch (msg.what) {
274                 case MSG_SEND_BROADCAST:
275                     prepareAndSendBroadcast((Intent) msg.obj, null);
276                     break;
277                 case MSG_SEND_DEFERRED_BROADCAST:
278                     Intent deferredIntent;
279                     synchronized (mLock) {
280                         deferredIntent = mDeferredMap.remove((String) msg.obj);
281                     }
282                     if (deferredIntent != null) {
283                         prepareAndSendBroadcast(deferredIntent,
284                                 createBroadcastOptions(deferredIntent));
285                     }
286                     break;
287             }
288         }
289 
prepareAndSendBroadcast(Intent intent, Bundle options)290         private void prepareAndSendBroadcast(Intent intent, Bundle options) {
291             if (!DropBoxManagerService.this.mBooted) {
292                 intent.addFlags(Intent.FLAG_RECEIVER_REGISTERED_ONLY);
293             }
294             getContext().sendBroadcastAsUser(intent, UserHandle.ALL,
295                     android.Manifest.permission.READ_LOGS, options);
296         }
297 
createIntent(String tag, long time)298         private Intent createIntent(String tag, long time) {
299             final Intent dropboxIntent = new Intent(DropBoxManager.ACTION_DROPBOX_ENTRY_ADDED);
300             dropboxIntent.putExtra(DropBoxManager.EXTRA_TAG, tag);
301             dropboxIntent.putExtra(DropBoxManager.EXTRA_TIME, time);
302             dropboxIntent.putExtra(DropBoxManager.EXTRA_DROPPED_COUNT, 0);
303             return dropboxIntent;
304         }
305 
createBroadcastOptions(Intent intent)306         private Bundle createBroadcastOptions(Intent intent) {
307             final BundleMerger extrasMerger = new BundleMerger();
308             extrasMerger.setDefaultMergeStrategy(BundleMerger.STRATEGY_FIRST);
309             extrasMerger.setMergeStrategy(DropBoxManager.EXTRA_TIME,
310                     BundleMerger.STRATEGY_COMPARABLE_MAX);
311             extrasMerger.setMergeStrategy(DropBoxManager.EXTRA_DROPPED_COUNT,
312                     BundleMerger.STRATEGY_NUMBER_INCREMENT_FIRST_AND_ADD);
313 
314             return BroadcastOptions.makeBasic()
315                     .setDeliveryGroupPolicy(BroadcastOptions.DELIVERY_GROUP_POLICY_MERGED)
316                     .setDeliveryGroupMatchingKey(DropBoxManager.ACTION_DROPBOX_ENTRY_ADDED,
317                             intent.getStringExtra(DropBoxManager.EXTRA_TAG))
318                     .setDeliveryGroupExtrasMerger(extrasMerger)
319                     .setDeferralPolicy(BroadcastOptions.DEFERRAL_POLICY_UNTIL_ACTIVE)
320                     .toBundle();
321         }
322 
323         /**
324          * Schedule a dropbox broadcast to be sent asynchronously.
325          */
sendBroadcast(String tag, long time)326         public void sendBroadcast(String tag, long time) {
327             sendMessage(obtainMessage(MSG_SEND_BROADCAST, createIntent(tag, time)));
328         }
329 
330         /**
331          * Possibly schedule a delayed dropbox broadcast. The broadcast will only be scheduled if
332          * no broadcast is currently scheduled. Otherwise updated the scheduled broadcast with the
333          * new intent information, effectively dropping the previous broadcast.
334          */
maybeDeferBroadcast(String tag, long time)335         public void maybeDeferBroadcast(String tag, long time) {
336             synchronized (mLock) {
337                 final Intent intent = mDeferredMap.get(tag);
338                 if (intent == null) {
339                     // Schedule new delayed broadcast.
340                     mDeferredMap.put(tag, createIntent(tag, time));
341                     sendMessageDelayed(obtainMessage(MSG_SEND_DEFERRED_BROADCAST, tag),
342                             mLowPriorityRateLimitPeriod);
343                 } else {
344                     // Broadcast is already scheduled. Update intent with new data.
345                     intent.putExtra(DropBoxManager.EXTRA_TIME, time);
346                     final int dropped = intent.getIntExtra(DropBoxManager.EXTRA_DROPPED_COUNT, 0);
347                     intent.putExtra(DropBoxManager.EXTRA_DROPPED_COUNT, dropped + 1);
348                     return;
349                 }
350             }
351         }
352     }
353 
354     /**
355      * Creates an instance of managed drop box storage using the default dropbox
356      * directory.
357      *
358      * @param context to use for receiving free space & gservices intents
359      */
DropBoxManagerService(final Context context)360     public DropBoxManagerService(final Context context) {
361         this(context, new File("/data/system/dropbox"), FgThread.get().getLooper());
362     }
363 
364     /**
365      * Creates an instance of managed drop box storage.  Normally there is one of these
366      * run by the system, but others can be created for testing and other purposes.
367      *
368      * @param context to use for receiving free space & gservices intents
369      * @param path to store drop box entries in
370      */
371     @VisibleForTesting
DropBoxManagerService(final Context context, File path, Looper looper)372     public DropBoxManagerService(final Context context, File path, Looper looper) {
373         super(context);
374         mDropBoxDir = path;
375         mContentResolver = getContext().getContentResolver();
376         mHandler = new DropBoxManagerBroadcastHandler(looper);
377         LocalServices.addService(DropBoxManagerInternal.class, new DropBoxManagerInternalImpl());
378     }
379 
380     @Override
onStart()381     public void onStart() {
382         publishBinderService(Context.DROPBOX_SERVICE, mStub);
383 
384         // The real work gets done lazily in init() -- that way service creation always
385         // succeeds, and things like disk problems cause individual method failures.
386     }
387 
388     @Override
onBootPhase(int phase)389     public void onBootPhase(int phase) {
390         switch (phase) {
391             case PHASE_SYSTEM_SERVICES_READY:
392                 IntentFilter filter = new IntentFilter();
393                 filter.addAction(Intent.ACTION_DEVICE_STORAGE_LOW);
394                 getContext().registerReceiver(mReceiver, filter);
395 
396                 mContentResolver.registerContentObserver(
397                     Settings.Global.CONTENT_URI, true,
398                     new ContentObserver(new Handler()) {
399                         @Override
400                         public void onChange(boolean selfChange) {
401                             mReceiver.onReceive(getContext(), (Intent) null);
402                         }
403                     });
404 
405                 getLowPriorityResourceConfigs();
406                 break;
407 
408             case PHASE_BOOT_COMPLETED:
409                 mBooted = true;
410                 break;
411         }
412     }
413 
414     /** Retrieves the binder stub -- for test instances */
getServiceStub()415     public IDropBoxManagerService getServiceStub() {
416         return mStub;
417     }
418 
addData(String tag, byte[] data, int flags)419     public void addData(String tag, byte[] data, int flags) {
420         addEntry(tag, new ByteArrayInputStream(data), data.length, flags);
421     }
422 
addFile(String tag, ParcelFileDescriptor fd, int flags)423     public void addFile(String tag, ParcelFileDescriptor fd, int flags) {
424         final StructStat stat;
425         try {
426             stat = Os.fstat(fd.getFileDescriptor());
427 
428             // Verify caller isn't playing games with pipes or sockets
429             if (!OsConstants.S_ISREG(stat.st_mode)) {
430                 throw new IllegalArgumentException(tag + " entry must be real file");
431             }
432         } catch (ErrnoException e) {
433             throw new IllegalArgumentException(e);
434         }
435 
436         addEntry(tag, new ParcelFileDescriptor.AutoCloseInputStream(fd), stat.st_size, flags);
437     }
438 
addEntry(String tag, InputStream in, long length, int flags)439     public void addEntry(String tag, InputStream in, long length, int flags) {
440         // If entry being added is large, and if it's not already compressed,
441         // then we'll force compress it during write
442         boolean forceCompress = false;
443         if ((flags & DropBoxManager.IS_GZIPPED) == 0
444                 && length > COMPRESS_THRESHOLD_BYTES) {
445             forceCompress = true;
446             flags |= DropBoxManager.IS_GZIPPED;
447         }
448 
449         addEntry(tag, new SimpleEntrySource(in, length, forceCompress), flags);
450     }
451 
452     /**
453      * Simple entry which contains data ready to be written.
454      */
455     public static class SimpleEntrySource implements EntrySource {
456         private final InputStream in;
457         private final long length;
458         private final boolean forceCompress;
459 
SimpleEntrySource(InputStream in, long length, boolean forceCompress)460         public SimpleEntrySource(InputStream in, long length, boolean forceCompress) {
461             this.in = in;
462             this.length = length;
463             this.forceCompress = forceCompress;
464         }
465 
length()466         public long length() {
467             return length;
468         }
469 
470         @Override
writeTo(FileDescriptor fd)471         public void writeTo(FileDescriptor fd) throws IOException {
472             // No need to buffer the output here, since data is either coming
473             // from an in-memory buffer, or another file on disk; if we buffered
474             // we'd lose out on sendfile() optimizations
475             if (forceCompress) {
476                 final GZIPOutputStream gzipOutputStream =
477                         new GZIPOutputStream(new FileOutputStream(fd));
478                 FileUtils.copy(in, gzipOutputStream);
479                 gzipOutputStream.close();
480             } else {
481                 FileUtils.copy(in, new FileOutputStream(fd));
482             }
483         }
484 
485         @Override
close()486         public void close() throws IOException {
487             FileUtils.closeQuietly(in);
488         }
489     }
490 
addEntry(String tag, EntrySource entry, int flags)491     public void addEntry(String tag, EntrySource entry, int flags) {
492         File temp = null;
493         try {
494             Slog.i(TAG, "add tag=" + tag + " isTagEnabled=" + isTagEnabled(tag)
495                     + " flags=0x" + Integer.toHexString(flags));
496             if ((flags & DropBoxManager.IS_EMPTY) != 0) throw new IllegalArgumentException();
497 
498             init();
499 
500             // Bail early if we know tag is disabled
501             if (!isTagEnabled(tag)) return;
502 
503             // Drop entries which are too large for our quota
504             final long length = entry.length();
505             final long max = trimToFit();
506             if (length > max) {
507                 // Log and fall through to create empty tombstone below
508                 Slog.w(TAG, "Dropping: " + tag + " (" + length + " > " + max + " bytes)");
509                 logDropboxDropped(
510                         FrameworkStatsLog.DROPBOX_ENTRY_DROPPED__DROP_REASON__ENTRY_TOO_LARGE,
511                         tag,
512                         0);
513             } else {
514                 temp = new File(mDropBoxDir, "drop" + Thread.currentThread().getId() + ".tmp");
515                 try (FileOutputStream out = new FileOutputStream(temp)) {
516                     entry.writeTo(out.getFD());
517                 }
518             }
519 
520             // Writing above succeeded, so create the finalized entry
521             long time = createEntry(temp, tag, flags);
522             temp = null;
523 
524             // Call sendBroadcast after returning from this call to avoid deadlock. In particular
525             // the caller may be holding the WindowManagerService lock but sendBroadcast requires a
526             // lock in ActivityManagerService. ActivityManagerService has been caught holding that
527             // very lock while waiting for the WindowManagerService lock.
528             if (mLowPriorityTags != null && mLowPriorityTags.contains(tag)) {
529                 // Rate limit low priority Dropbox entries
530                 mHandler.maybeDeferBroadcast(tag, time);
531             } else {
532                 mHandler.sendBroadcast(tag, time);
533             }
534         } catch (IOException e) {
535             Slog.e(TAG, "Can't write: " + tag, e);
536             logDropboxDropped(
537                     FrameworkStatsLog.DROPBOX_ENTRY_DROPPED__DROP_REASON__WRITE_FAILURE,
538                     tag,
539                     0);
540         } finally {
541             IoUtils.closeQuietly(entry);
542             if (temp != null) temp.delete();
543         }
544     }
545 
logDropboxDropped(int reason, String tag, long entryAge)546     private void logDropboxDropped(int reason, String tag, long entryAge) {
547         FrameworkStatsLog.write(FrameworkStatsLog.DROPBOX_ENTRY_DROPPED, reason, tag, entryAge);
548     }
549 
isTagEnabled(String tag)550     public boolean isTagEnabled(String tag) {
551         final long token = Binder.clearCallingIdentity();
552         try {
553             if (DISABLED_BY_DEFAULT_TAGS.contains(tag)) {
554                 return "enabled".equals(Settings.Global.getString(
555                     mContentResolver, Settings.Global.DROPBOX_TAG_PREFIX + tag));
556             } else {
557                 return !"disabled".equals(Settings.Global.getString(
558                     mContentResolver, Settings.Global.DROPBOX_TAG_PREFIX + tag));
559             }
560         } finally {
561             Binder.restoreCallingIdentity(token);
562         }
563     }
564 
checkPermission(int callingUid, String callingPackage, @Nullable String callingAttributionTag)565     private boolean checkPermission(int callingUid, String callingPackage,
566             @Nullable String callingAttributionTag) {
567         // If callers have this permission, then we don't need to check
568         // USAGE_STATS, because they are part of the system and have agreed to
569         // check USAGE_STATS before passing the data along.
570         if (getContext().checkCallingPermission(android.Manifest.permission.PEEK_DROPBOX_DATA)
571                 == PackageManager.PERMISSION_GRANTED) {
572             return true;
573         }
574 
575         // Callers always need this permission
576         getContext().enforceCallingOrSelfPermission(
577                 android.Manifest.permission.READ_LOGS, TAG);
578 
579         // Callers also need the ability to read usage statistics
580         switch (getContext().getSystemService(AppOpsManager.class).noteOp(
581                 AppOpsManager.OP_GET_USAGE_STATS, callingUid, callingPackage, callingAttributionTag,
582                 null)) {
583             case AppOpsManager.MODE_ALLOWED:
584                 return true;
585             case AppOpsManager.MODE_DEFAULT:
586                 getContext().enforceCallingOrSelfPermission(
587                         android.Manifest.permission.PACKAGE_USAGE_STATS, TAG);
588                 return true;
589             default:
590                 return false;
591         }
592     }
593 
getNextEntry(String tag, long millis, String callingPackage, @Nullable String callingAttributionTag)594     public synchronized DropBoxManager.Entry getNextEntry(String tag, long millis,
595             String callingPackage, @Nullable String callingAttributionTag) {
596         if (!checkPermission(Binder.getCallingUid(), callingPackage, callingAttributionTag)) {
597             return null;
598         }
599 
600         try {
601             init();
602         } catch (IOException e) {
603             Slog.e(TAG, "Can't init", e);
604             return null;
605         }
606 
607         FileList list = tag == null ? mAllFiles : mFilesByTag.get(tag);
608         if (list == null) return null;
609 
610         for (EntryFile entry : list.contents.tailSet(new EntryFile(millis + 1))) {
611             if (entry.tag == null) continue;
612             if ((entry.flags & DropBoxManager.IS_EMPTY) != 0) {
613                 return new DropBoxManager.Entry(entry.tag, entry.timestampMillis);
614             }
615             final File file = entry.getFile(mDropBoxDir);
616             try {
617                 return new DropBoxManager.Entry(
618                         entry.tag, entry.timestampMillis, file, entry.flags);
619             } catch (IOException e) {
620                 Slog.wtf(TAG, "Can't read: " + file, e);
621                 // Continue to next file
622             }
623         }
624 
625         return null;
626     }
627 
setLowPriorityRateLimit(long period)628     private synchronized void setLowPriorityRateLimit(long period) {
629         mLowPriorityRateLimitPeriod = period;
630     }
631 
addLowPriorityTag(String tag)632     private synchronized void addLowPriorityTag(String tag) {
633         mLowPriorityTags.add(tag);
634     }
635 
removeLowPriorityTag(String tag)636     private synchronized void removeLowPriorityTag(String tag) {
637         mLowPriorityTags.remove(tag);
638     }
639 
restoreDefaults()640     private synchronized void restoreDefaults() {
641         getLowPriorityResourceConfigs();
642     }
643 
dump(FileDescriptor fd, PrintWriter pw, String[] args)644     public synchronized void dump(FileDescriptor fd, PrintWriter pw, String[] args) {
645         if (!DumpUtils.checkDumpAndUsageStatsPermission(getContext(), TAG, pw)) return;
646 
647         try {
648             init();
649         } catch (IOException e) {
650             pw.println("Can't initialize: " + e);
651             Slog.e(TAG, "Can't init", e);
652             return;
653         }
654 
655         if (PROFILE_DUMP) Debug.startMethodTracing("/data/trace/dropbox.dump");
656 
657         StringBuilder out = new StringBuilder();
658         boolean doPrint = false, doFile = false;
659         boolean dumpProto = false;
660         ArrayList<String> searchArgs = new ArrayList<String>();
661         for (int i = 0; args != null && i < args.length; i++) {
662             if (args[i].equals("-p") || args[i].equals("--print")) {
663                 doPrint = true;
664             } else if (args[i].equals("-f") || args[i].equals("--file")) {
665                 doFile = true;
666             } else if (args[i].equals("--proto")) {
667                 dumpProto = true;
668             } else if (args[i].equals("-h") || args[i].equals("--help")) {
669                 pw.println("Dropbox (dropbox) dump options:");
670                 pw.println("  [-h|--help] [-p|--print] [-f|--file] [timestamp]");
671                 pw.println("    -h|--help: print this help");
672                 pw.println("    -p|--print: print full contents of each entry");
673                 pw.println("    -f|--file: print path of each entry's file");
674                 pw.println("    --proto: dump data to proto");
675                 pw.println("  [timestamp] optionally filters to only those entries.");
676                 return;
677             } else if (args[i].startsWith("-")) {
678                 out.append("Unknown argument: ").append(args[i]).append("\n");
679             } else {
680                 searchArgs.add(args[i]);
681             }
682         }
683 
684         if (dumpProto) {
685             dumpProtoLocked(fd, searchArgs);
686             return;
687         }
688 
689         out.append("Drop box contents: ").append(mAllFiles.contents.size()).append(" entries\n");
690         out.append("Max entries: ").append(mMaxFiles).append("\n");
691 
692         out.append("Low priority rate limit period: ");
693         out.append(mLowPriorityRateLimitPeriod).append(" ms\n");
694         out.append("Low priority tags: ").append(mLowPriorityTags).append("\n");
695 
696         if (!searchArgs.isEmpty()) {
697             out.append("Searching for:");
698             for (String a : searchArgs) out.append(" ").append(a);
699             out.append("\n");
700         }
701 
702         int numFound = 0;
703         out.append("\n");
704         for (EntryFile entry : mAllFiles.contents) {
705             if (!matchEntry(entry, searchArgs)) continue;
706 
707             numFound++;
708             if (doPrint) out.append("========================================\n");
709 
710             String date = TimeMigrationUtils.formatMillisWithFixedFormat(entry.timestampMillis);
711             out.append(date).append(" ").append(entry.tag == null ? "(no tag)" : entry.tag);
712 
713             final File file = entry.getFile(mDropBoxDir);
714             if (file == null) {
715                 out.append(" (no file)\n");
716                 continue;
717             } else if ((entry.flags & DropBoxManager.IS_EMPTY) != 0) {
718                 out.append(" (contents lost)\n");
719                 continue;
720             } else {
721                 out.append(" (");
722                 if ((entry.flags & DropBoxManager.IS_GZIPPED) != 0) out.append("compressed ");
723                 out.append((entry.flags & DropBoxManager.IS_TEXT) != 0 ? "text" : "data");
724                 out.append(", ").append(file.length()).append(" bytes)\n");
725             }
726 
727             if (doFile || (doPrint && (entry.flags & DropBoxManager.IS_TEXT) == 0)) {
728                 if (!doPrint) out.append("    ");
729                 out.append(file.getPath()).append("\n");
730             }
731 
732             if ((entry.flags & DropBoxManager.IS_TEXT) != 0 && doPrint) {
733                 DropBoxManager.Entry dbe = null;
734                 InputStreamReader isr = null;
735                 try {
736                     dbe = new DropBoxManager.Entry(
737                              entry.tag, entry.timestampMillis, file, entry.flags);
738 
739                     if (doPrint) {
740                         isr = new InputStreamReader(dbe.getInputStream());
741                         char[] buf = new char[4096];
742                         boolean newline = false;
743                         for (;;) {
744                             int n = isr.read(buf);
745                             if (n <= 0) break;
746                             out.append(buf, 0, n);
747                             newline = (buf[n - 1] == '\n');
748 
749                             // Flush periodically when printing to avoid out-of-memory.
750                             if (out.length() > 65536) {
751                                 pw.write(out.toString());
752                                 out.setLength(0);
753                             }
754                         }
755                         if (!newline) out.append("\n");
756                     }
757                 } catch (IOException e) {
758                     out.append("*** ").append(e.toString()).append("\n");
759                     Slog.e(TAG, "Can't read: " + file, e);
760                 } finally {
761                     if (dbe != null) dbe.close();
762                     if (isr != null) {
763                         try {
764                             isr.close();
765                         } catch (IOException unused) {
766                         }
767                     }
768                 }
769             }
770 
771             if (doPrint) out.append("\n");
772         }
773 
774         if (numFound == 0) out.append("(No entries found.)\n");
775 
776         if (args == null || args.length == 0) {
777             if (!doPrint) out.append("\n");
778             out.append("Usage: dumpsys dropbox [--print|--file] [YYYY-mm-dd] [HH:MM:SS] [tag]\n");
779         }
780 
781         pw.write(out.toString());
782         if (PROFILE_DUMP) Debug.stopMethodTracing();
783     }
784 
matchEntry(EntryFile entry, ArrayList<String> searchArgs)785     private boolean matchEntry(EntryFile entry, ArrayList<String> searchArgs) {
786         String date = TimeMigrationUtils.formatMillisWithFixedFormat(entry.timestampMillis);
787         boolean match = true;
788         int numArgs = searchArgs.size();
789         for (int i = 0; i < numArgs && match; i++) {
790             String arg = searchArgs.get(i);
791             match = (date.contains(arg) || arg.equals(entry.tag));
792         }
793         return match;
794     }
795 
dumpProtoLocked(FileDescriptor fd, ArrayList<String> searchArgs)796     private void dumpProtoLocked(FileDescriptor fd, ArrayList<String> searchArgs) {
797         final ProtoOutputStream proto = new ProtoOutputStream(fd);
798 
799         for (EntryFile entry : mAllFiles.contents) {
800             if (!matchEntry(entry, searchArgs)) continue;
801 
802             final File file = entry.getFile(mDropBoxDir);
803             if ((file == null) || ((entry.flags & DropBoxManager.IS_EMPTY) != 0)) {
804                 continue;
805             }
806 
807             final long bToken = proto.start(DropBoxManagerServiceDumpProto.ENTRIES);
808             proto.write(DropBoxManagerServiceDumpProto.Entry.TIME_MS, entry.timestampMillis);
809             try (
810                 DropBoxManager.Entry dbe = new DropBoxManager.Entry(
811                         entry.tag, entry.timestampMillis, file, entry.flags);
812                 InputStream is = dbe.getInputStream();
813             ) {
814                 if (is != null) {
815                     byte[] buf = new byte[PROTO_MAX_DATA_BYTES];
816                     int readBytes = 0;
817                     int n = 0;
818                     while (n >= 0 && (readBytes += n) < PROTO_MAX_DATA_BYTES) {
819                         n = is.read(buf, readBytes, PROTO_MAX_DATA_BYTES - readBytes);
820                     }
821                     proto.write(DropBoxManagerServiceDumpProto.Entry.DATA,
822                             Arrays.copyOf(buf, readBytes));
823                 }
824             } catch (IOException e) {
825                 Slog.e(TAG, "Can't read: " + file, e);
826             }
827 
828             proto.end(bToken);
829         }
830 
831         proto.flush();
832     }
833 
834     ///////////////////////////////////////////////////////////////////////////
835 
836     /** Chronologically sorted list of {@link EntryFile} */
837     private static final class FileList implements Comparable<FileList> {
838         public int blocks = 0;
839         public final TreeSet<EntryFile> contents = new TreeSet<EntryFile>();
840 
841         /** Sorts bigger FileList instances before smaller ones. */
compareTo(FileList o)842         public final int compareTo(FileList o) {
843             if (blocks != o.blocks) return o.blocks - blocks;
844             if (this == o) return 0;
845             if (hashCode() < o.hashCode()) return -1;
846             if (hashCode() > o.hashCode()) return 1;
847             return 0;
848         }
849     }
850 
851     /**
852      * Metadata describing an on-disk log file.
853      *
854      * Note its instances do no have knowledge on what directory they're stored, just to save
855      * 4/8 bytes per instance.  Instead, {@link #getFile} takes a directory so it can build a
856      * fullpath.
857      */
858     @VisibleForTesting
859     static final class EntryFile implements Comparable<EntryFile> {
860         public final String tag;
861         public final long timestampMillis;
862         public final int flags;
863         public final int blocks;
864 
865         /** Sorts earlier EntryFile instances before later ones. */
compareTo(EntryFile o)866         public final int compareTo(EntryFile o) {
867             int comp = Long.compare(timestampMillis, o.timestampMillis);
868             if (comp != 0) return comp;
869 
870             comp = ObjectUtils.compare(tag, o.tag);
871             if (comp != 0) return comp;
872 
873             comp = Integer.compare(flags, o.flags);
874             if (comp != 0) return comp;
875 
876             return Integer.compare(hashCode(), o.hashCode());
877         }
878 
879         /**
880          * Moves an existing temporary file to a new log filename.
881          *
882          * @param temp file to rename
883          * @param dir to store file in
884          * @param tag to use for new log file name
885          * @param timestampMillis of log entry
886          * @param flags for the entry data
887          * @param blockSize to use for space accounting
888          * @throws IOException if the file can't be moved
889          */
EntryFile(File temp, File dir, String tag,long timestampMillis, int flags, int blockSize)890         public EntryFile(File temp, File dir, String tag,long timestampMillis,
891                          int flags, int blockSize) throws IOException {
892             if ((flags & DropBoxManager.IS_EMPTY) != 0) throw new IllegalArgumentException();
893 
894             this.tag = TextUtils.safeIntern(tag);
895             this.timestampMillis = timestampMillis;
896             this.flags = flags;
897 
898             final File file = this.getFile(dir);
899             if (!temp.renameTo(file)) {
900                 throw new IOException("Can't rename " + temp + " to " + file);
901             }
902             this.blocks = (int) ((file.length() + blockSize - 1) / blockSize);
903         }
904 
905         /**
906          * Creates a zero-length tombstone for a file whose contents were lost.
907          *
908          * @param dir to store file in
909          * @param tag to use for new log file name
910          * @param timestampMillis of log entry
911          * @throws IOException if the file can't be created.
912          */
EntryFile(File dir, String tag, long timestampMillis)913         public EntryFile(File dir, String tag, long timestampMillis) throws IOException {
914             this.tag = TextUtils.safeIntern(tag);
915             this.timestampMillis = timestampMillis;
916             this.flags = DropBoxManager.IS_EMPTY;
917             this.blocks = 0;
918             new FileOutputStream(getFile(dir)).close();
919         }
920 
921         /**
922          * Extracts metadata from an existing on-disk log filename.
923          *
924          * Note when a filename is not recognizable, it will create an instance that
925          * {@link #hasFile()} would return false on, and also remove the file.
926          *
927          * @param file name of existing log file
928          * @param blockSize to use for space accounting
929          */
EntryFile(File file, int blockSize)930         public EntryFile(File file, int blockSize) {
931 
932             boolean parseFailure = false;
933 
934             String name = file.getName();
935             int flags = 0;
936             String tag = null;
937             long millis = 0;
938 
939             final int at = name.lastIndexOf('@');
940             if (at < 0) {
941                 parseFailure = true;
942             } else {
943                 tag = Uri.decode(name.substring(0, at));
944                 if (name.endsWith(".gz")) {
945                     flags |= DropBoxManager.IS_GZIPPED;
946                     name = name.substring(0, name.length() - 3);
947                 }
948                 if (name.endsWith(".lost")) {
949                     flags |= DropBoxManager.IS_EMPTY;
950                     name = name.substring(at + 1, name.length() - 5);
951                 } else if (name.endsWith(".txt")) {
952                     flags |= DropBoxManager.IS_TEXT;
953                     name = name.substring(at + 1, name.length() - 4);
954                 } else if (name.endsWith(".dat")) {
955                     name = name.substring(at + 1, name.length() - 4);
956                 } else {
957                     parseFailure = true;
958                 }
959                 if (!parseFailure) {
960                     try {
961                         millis = Long.parseLong(name);
962                     } catch (NumberFormatException e) {
963                         parseFailure = true;
964                     }
965                 }
966             }
967             if (parseFailure) {
968                 Slog.wtf(TAG, "Invalid filename: " + file);
969 
970                 // Remove the file and return an empty instance.
971                 file.delete();
972                 this.tag = null;
973                 this.flags = DropBoxManager.IS_EMPTY;
974                 this.timestampMillis = 0;
975                 this.blocks = 0;
976                 return;
977             }
978 
979             this.blocks = (int) ((file.length() + blockSize - 1) / blockSize);
980             this.tag = TextUtils.safeIntern(tag);
981             this.flags = flags;
982             this.timestampMillis = millis;
983         }
984 
985         /**
986          * Creates a EntryFile object with only a timestamp for comparison purposes.
987          * @param millis to compare with.
988          */
EntryFile(long millis)989         public EntryFile(long millis) {
990             this.tag = null;
991             this.timestampMillis = millis;
992             this.flags = DropBoxManager.IS_EMPTY;
993             this.blocks = 0;
994         }
995 
996         /**
997          * @return whether an entry actually has a backing file, or it's an empty "tombstone"
998          * entry.
999          */
hasFile()1000         public boolean hasFile() {
1001             return tag != null;
1002         }
1003 
1004         /** @return File extension for the flags. */
getExtension()1005         private String getExtension() {
1006             if ((flags &  DropBoxManager.IS_EMPTY) != 0) {
1007                 return ".lost";
1008             }
1009             return ((flags & DropBoxManager.IS_TEXT) != 0 ? ".txt" : ".dat") +
1010                     ((flags & DropBoxManager.IS_GZIPPED) != 0 ? ".gz" : "");
1011         }
1012 
1013         /**
1014          * @return filename for this entry without the pathname.
1015          */
getFilename()1016         public String getFilename() {
1017             return hasFile() ? Uri.encode(tag) + "@" + timestampMillis + getExtension() : null;
1018         }
1019 
1020         /**
1021          * Get a full-path {@link File} representing this entry.
1022          * @param dir Parent directly.  The caller needs to pass it because {@link EntryFile}s don't
1023          *            know in which directory they're stored.
1024          */
getFile(File dir)1025         public File getFile(File dir) {
1026             return hasFile() ? new File(dir, getFilename()) : null;
1027         }
1028 
1029         /**
1030          * If an entry has a backing file, remove it.
1031          */
deleteFile(File dir)1032         public void deleteFile(File dir) {
1033             if (hasFile()) {
1034                 getFile(dir).delete();
1035             }
1036         }
1037     }
1038 
1039     ///////////////////////////////////////////////////////////////////////////
1040 
1041     /** If never run before, scans disk contents to build in-memory tracking data. */
init()1042     private synchronized void init() throws IOException {
1043         if (mStatFs == null) {
1044             if (!mDropBoxDir.isDirectory() && !mDropBoxDir.mkdirs()) {
1045                 throw new IOException("Can't mkdir: " + mDropBoxDir);
1046             }
1047             try {
1048                 mStatFs = new StatFs(mDropBoxDir.getPath());
1049                 mBlockSize = mStatFs.getBlockSize();
1050             } catch (IllegalArgumentException e) {  // StatFs throws this on error
1051                 throw new IOException("Can't statfs: " + mDropBoxDir);
1052             }
1053         }
1054 
1055         if (mAllFiles == null) {
1056             File[] files = mDropBoxDir.listFiles();
1057             if (files == null) throw new IOException("Can't list files: " + mDropBoxDir);
1058 
1059             mAllFiles = new FileList();
1060             mFilesByTag = new ArrayMap<>();
1061 
1062             // Scan pre-existing files.
1063             for (File file : files) {
1064                 if (file.getName().endsWith(".tmp")) {
1065                     Slog.i(TAG, "Cleaning temp file: " + file);
1066                     file.delete();
1067                     continue;
1068                 }
1069 
1070                 EntryFile entry = new EntryFile(file, mBlockSize);
1071 
1072                 if (entry.hasFile()) {
1073                     // Enroll only when the filename is valid.  Otherwise the above constructor
1074                     // has removed the file already.
1075                     enrollEntry(entry);
1076                 }
1077             }
1078         }
1079     }
1080 
1081     /** Adds a disk log file to in-memory tracking for accounting and enumeration. */
enrollEntry(EntryFile entry)1082     private synchronized void enrollEntry(EntryFile entry) {
1083         mAllFiles.contents.add(entry);
1084         mAllFiles.blocks += entry.blocks;
1085 
1086         // mFilesByTag is used for trimming, so don't list empty files.
1087         // (Zero-length/lost files are trimmed by date from mAllFiles.)
1088 
1089         if (entry.hasFile() && entry.blocks > 0) {
1090             FileList tagFiles = mFilesByTag.get(entry.tag);
1091             if (tagFiles == null) {
1092                 tagFiles = new FileList();
1093                 mFilesByTag.put(TextUtils.safeIntern(entry.tag), tagFiles);
1094             }
1095             tagFiles.contents.add(entry);
1096             tagFiles.blocks += entry.blocks;
1097         }
1098     }
1099 
1100     /** Moves a temporary file to a final log filename and enrolls it. */
createEntry(File temp, String tag, int flags)1101     private synchronized long createEntry(File temp, String tag, int flags) throws IOException {
1102         long t = System.currentTimeMillis();
1103 
1104         // Require each entry to have a unique timestamp; if there are entries
1105         // >10sec in the future (due to clock skew), drag them back to avoid
1106         // keeping them around forever.
1107 
1108         SortedSet<EntryFile> tail = mAllFiles.contents.tailSet(new EntryFile(t + 10000));
1109         EntryFile[] future = null;
1110         if (!tail.isEmpty()) {
1111             future = tail.toArray(new EntryFile[tail.size()]);
1112             tail.clear();  // Remove from mAllFiles
1113         }
1114 
1115         if (!mAllFiles.contents.isEmpty()) {
1116             t = Math.max(t, mAllFiles.contents.last().timestampMillis + 1);
1117         }
1118 
1119         if (future != null) {
1120             for (EntryFile late : future) {
1121                 mAllFiles.blocks -= late.blocks;
1122                 FileList tagFiles = mFilesByTag.get(late.tag);
1123                 if (tagFiles != null && tagFiles.contents.remove(late)) {
1124                     tagFiles.blocks -= late.blocks;
1125                 }
1126                 if ((late.flags & DropBoxManager.IS_EMPTY) == 0) {
1127                     enrollEntry(new EntryFile(late.getFile(mDropBoxDir), mDropBoxDir,
1128                             late.tag, t++, late.flags, mBlockSize));
1129                 } else {
1130                     enrollEntry(new EntryFile(mDropBoxDir, late.tag, t++));
1131                 }
1132             }
1133         }
1134 
1135         if (temp == null) {
1136             enrollEntry(new EntryFile(mDropBoxDir, tag, t));
1137         } else {
1138             enrollEntry(new EntryFile(temp, mDropBoxDir, tag, t, flags, mBlockSize));
1139         }
1140         return t;
1141     }
1142 
1143     /**
1144      * Trims the files on disk to make sure they aren't using too much space.
1145      * @return the overall quota for storage (in bytes)
1146      */
trimToFit()1147     private synchronized long trimToFit() throws IOException {
1148         // Expunge aged items (including tombstones marking deleted data).
1149 
1150         int ageSeconds = Settings.Global.getInt(mContentResolver,
1151                 Settings.Global.DROPBOX_AGE_SECONDS, DEFAULT_AGE_SECONDS);
1152         mMaxFiles = Settings.Global.getInt(mContentResolver,
1153                 Settings.Global.DROPBOX_MAX_FILES,
1154                 (ActivityManager.isLowRamDeviceStatic()
1155                         ?  DEFAULT_MAX_FILES_LOWRAM : DEFAULT_MAX_FILES));
1156         long curTimeMillis = System.currentTimeMillis();
1157         long cutoffMillis = curTimeMillis - ageSeconds * 1000;
1158         while (!mAllFiles.contents.isEmpty()) {
1159             EntryFile entry = mAllFiles.contents.first();
1160             if (entry.timestampMillis > cutoffMillis && mAllFiles.contents.size() < mMaxFiles) {
1161                 break;
1162             }
1163 
1164             logDropboxDropped(
1165                     FrameworkStatsLog.DROPBOX_ENTRY_DROPPED__DROP_REASON__AGED,
1166                     entry.tag,
1167                     curTimeMillis - entry.timestampMillis);
1168 
1169             FileList tag = mFilesByTag.get(entry.tag);
1170             if (tag != null && tag.contents.remove(entry)) tag.blocks -= entry.blocks;
1171             if (mAllFiles.contents.remove(entry)) mAllFiles.blocks -= entry.blocks;
1172             entry.deleteFile(mDropBoxDir);
1173         }
1174 
1175         // Compute overall quota (a fraction of available free space) in blocks.
1176         // The quota changes dynamically based on the amount of free space;
1177         // that way when lots of data is available we can use it, but we'll get
1178         // out of the way if storage starts getting tight.
1179 
1180         long uptimeMillis = SystemClock.uptimeMillis();
1181         if (uptimeMillis > mCachedQuotaUptimeMillis + QUOTA_RESCAN_MILLIS) {
1182             int quotaPercent = Settings.Global.getInt(mContentResolver,
1183                     Settings.Global.DROPBOX_QUOTA_PERCENT, DEFAULT_QUOTA_PERCENT);
1184             int reservePercent = Settings.Global.getInt(mContentResolver,
1185                     Settings.Global.DROPBOX_RESERVE_PERCENT, DEFAULT_RESERVE_PERCENT);
1186             int quotaKb = Settings.Global.getInt(mContentResolver,
1187                     Settings.Global.DROPBOX_QUOTA_KB, DEFAULT_QUOTA_KB);
1188 
1189             String dirPath = mDropBoxDir.getPath();
1190             try {
1191                 mStatFs.restat(dirPath);
1192             } catch (IllegalArgumentException e) {  // restat throws this on error
1193                 throw new IOException("Can't restat: " + mDropBoxDir);
1194             }
1195             long available = mStatFs.getAvailableBlocksLong();
1196             long nonreserved = available - mStatFs.getBlockCountLong() * reservePercent / 100;
1197             long maxAvailableLong = nonreserved * quotaPercent / 100;
1198             int maxAvailable = Math.toIntExact(Math.max(0,
1199                     Math.min(maxAvailableLong, Integer.MAX_VALUE)));
1200             int maximum = quotaKb * 1024 / mBlockSize;
1201             mCachedQuotaBlocks = Math.min(maximum, maxAvailable);
1202             mCachedQuotaUptimeMillis = uptimeMillis;
1203         }
1204 
1205         // If we're using too much space, delete old items to make room.
1206         //
1207         // We trim each tag independently (this is why we keep per-tag lists).
1208         // Space is "fairly" shared between tags -- they are all squeezed
1209         // equally until enough space is reclaimed.
1210         //
1211         // A single circular buffer (a la logcat) would be simpler, but this
1212         // way we can handle fat/bursty data (like 1MB+ bugreports, 300KB+
1213         // kernel crash dumps, and 100KB+ ANR reports) without swamping small,
1214         // well-behaved data streams (event statistics, profile data, etc).
1215         //
1216         // Deleted files are replaced with zero-length tombstones to mark what
1217         // was lost.  Tombstones are expunged by age (see above).
1218 
1219         if (mAllFiles.blocks > mCachedQuotaBlocks) {
1220             // Find a fair share amount of space to limit each tag
1221             int unsqueezed = mAllFiles.blocks, squeezed = 0;
1222             TreeSet<FileList> tags = new TreeSet<FileList>(mFilesByTag.values());
1223             for (FileList tag : tags) {
1224                 if (squeezed > 0 && tag.blocks <= (mCachedQuotaBlocks - unsqueezed) / squeezed) {
1225                     break;
1226                 }
1227                 unsqueezed -= tag.blocks;
1228                 squeezed++;
1229             }
1230             int tagQuota = (mCachedQuotaBlocks - unsqueezed) / squeezed;
1231 
1232             // Remove old items from each tag until it meets the per-tag quota.
1233             for (FileList tag : tags) {
1234                 if (mAllFiles.blocks < mCachedQuotaBlocks) break;
1235                 while (tag.blocks > tagQuota && !tag.contents.isEmpty()) {
1236                     EntryFile entry = tag.contents.first();
1237                     logDropboxDropped(
1238                             FrameworkStatsLog.DROPBOX_ENTRY_DROPPED__DROP_REASON__CLEARING_DATA,
1239                             entry.tag,
1240                             curTimeMillis - entry.timestampMillis);
1241 
1242                     if (tag.contents.remove(entry)) tag.blocks -= entry.blocks;
1243                     if (mAllFiles.contents.remove(entry)) mAllFiles.blocks -= entry.blocks;
1244 
1245                     try {
1246                         entry.deleteFile(mDropBoxDir);
1247                         enrollEntry(new EntryFile(mDropBoxDir, entry.tag, entry.timestampMillis));
1248                     } catch (IOException e) {
1249                         Slog.e(TAG, "Can't write tombstone file", e);
1250                     }
1251                 }
1252             }
1253         }
1254 
1255         return mCachedQuotaBlocks * mBlockSize;
1256     }
1257 
getLowPriorityResourceConfigs()1258     private void getLowPriorityResourceConfigs() {
1259         mLowPriorityRateLimitPeriod = Resources.getSystem().getInteger(
1260                 R.integer.config_dropboxLowPriorityBroadcastRateLimitPeriod);
1261 
1262         final String[] lowPrioritytags = Resources.getSystem().getStringArray(
1263                 R.array.config_dropboxLowPriorityTags);
1264         final int size = lowPrioritytags.length;
1265         if (size == 0) {
1266             mLowPriorityTags = null;
1267             return;
1268         }
1269         mLowPriorityTags = new ArraySet(size);
1270         for (int i = 0; i < size; i++) {
1271             mLowPriorityTags.add(lowPrioritytags[i]);
1272         }
1273     }
1274 
1275     private final class DropBoxManagerInternalImpl extends DropBoxManagerInternal {
1276         @Override
addEntry(String tag, EntrySource entry, int flags)1277         public void addEntry(String tag, EntrySource entry, int flags) {
1278             DropBoxManagerService.this.addEntry(tag, entry, flags);
1279         }
1280     }
1281 }
1282