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.content.BroadcastReceiver; 20 import android.content.ContentResolver; 21 import android.content.Context; 22 import android.content.Intent; 23 import android.content.IntentFilter; 24 import android.content.pm.PackageManager; 25 import android.database.ContentObserver; 26 import android.net.Uri; 27 import android.os.Binder; 28 import android.os.Debug; 29 import android.os.DropBoxManager; 30 import android.os.FileUtils; 31 import android.os.Handler; 32 import android.os.Message; 33 import android.os.StatFs; 34 import android.os.SystemClock; 35 import android.os.UserHandle; 36 import android.provider.Settings; 37 import android.text.format.Time; 38 import android.util.Slog; 39 40 import com.android.internal.os.IDropBoxManagerService; 41 42 import java.io.BufferedOutputStream; 43 import java.io.File; 44 import java.io.FileDescriptor; 45 import java.io.FileOutputStream; 46 import java.io.IOException; 47 import java.io.InputStream; 48 import java.io.InputStreamReader; 49 import java.io.OutputStream; 50 import java.io.PrintWriter; 51 import java.util.ArrayList; 52 import java.util.HashMap; 53 import java.util.SortedSet; 54 import java.util.TreeSet; 55 import java.util.zip.GZIPOutputStream; 56 57 /** 58 * Implementation of {@link IDropBoxManagerService} using the filesystem. 59 * Clients use {@link DropBoxManager} to access this service. 60 */ 61 public final class DropBoxManagerService extends IDropBoxManagerService.Stub { 62 private static final String TAG = "DropBoxManagerService"; 63 private static final int DEFAULT_AGE_SECONDS = 3 * 86400; 64 private static final int DEFAULT_MAX_FILES = 1000; 65 private static final int DEFAULT_QUOTA_KB = 5 * 1024; 66 private static final int DEFAULT_QUOTA_PERCENT = 10; 67 private static final int DEFAULT_RESERVE_PERCENT = 10; 68 private static final int QUOTA_RESCAN_MILLIS = 5000; 69 70 // mHandler 'what' value. 71 private static final int MSG_SEND_BROADCAST = 1; 72 73 private static final boolean PROFILE_DUMP = false; 74 75 // TODO: This implementation currently uses one file per entry, which is 76 // inefficient for smallish entries -- consider using a single queue file 77 // per tag (or even globally) instead. 78 79 // The cached context and derived objects 80 81 private final Context mContext; 82 private final ContentResolver mContentResolver; 83 private final File mDropBoxDir; 84 85 // Accounting of all currently written log files (set in init()). 86 87 private FileList mAllFiles = null; 88 private HashMap<String, FileList> mFilesByTag = null; 89 90 // Various bits of disk information 91 92 private StatFs mStatFs = null; 93 private int mBlockSize = 0; 94 private int mCachedQuotaBlocks = 0; // Space we can use: computed from free space, etc. 95 private long mCachedQuotaUptimeMillis = 0; 96 97 private volatile boolean mBooted = false; 98 99 // Provide a way to perform sendBroadcast asynchronously to avoid deadlocks. 100 private final Handler mHandler; 101 102 /** Receives events that might indicate a need to clean up files. */ 103 private final BroadcastReceiver mReceiver = new BroadcastReceiver() { 104 @Override 105 public void onReceive(Context context, Intent intent) { 106 if (intent != null && Intent.ACTION_BOOT_COMPLETED.equals(intent.getAction())) { 107 mBooted = true; 108 return; 109 } 110 111 // Else, for ACTION_DEVICE_STORAGE_LOW: 112 mCachedQuotaUptimeMillis = 0; // Force a re-check of quota size 113 114 // Run the initialization in the background (not this main thread). 115 // The init() and trimToFit() methods are synchronized, so they still 116 // block other users -- but at least the onReceive() call can finish. 117 new Thread() { 118 public void run() { 119 try { 120 init(); 121 trimToFit(); 122 } catch (IOException e) { 123 Slog.e(TAG, "Can't init", e); 124 } 125 } 126 }.start(); 127 } 128 }; 129 130 /** 131 * Creates an instance of managed drop box storage. Normally there is one of these 132 * run by the system, but others can be created for testing and other purposes. 133 * 134 * @param context to use for receiving free space & gservices intents 135 * @param path to store drop box entries in 136 */ 137 public DropBoxManagerService(final Context context, File path) { 138 mDropBoxDir = path; 139 140 // Set up intent receivers 141 mContext = context; 142 mContentResolver = context.getContentResolver(); 143 144 IntentFilter filter = new IntentFilter(); 145 filter.addAction(Intent.ACTION_DEVICE_STORAGE_LOW); 146 filter.addAction(Intent.ACTION_BOOT_COMPLETED); 147 context.registerReceiver(mReceiver, filter); 148 149 mContentResolver.registerContentObserver( 150 Settings.Global.CONTENT_URI, true, 151 new ContentObserver(new Handler()) { 152 @Override 153 public void onChange(boolean selfChange) { 154 mReceiver.onReceive(context, (Intent) null); 155 } 156 }); 157 158 mHandler = new Handler() { 159 @Override 160 public void handleMessage(Message msg) { 161 if (msg.what == MSG_SEND_BROADCAST) { 162 mContext.sendBroadcastAsUser((Intent)msg.obj, UserHandle.OWNER, 163 android.Manifest.permission.READ_LOGS); 164 } 165 } 166 }; 167 168 // The real work gets done lazily in init() -- that way service creation always 169 // succeeds, and things like disk problems cause individual method failures. 170 } 171 172 /** Unregisters broadcast receivers and any other hooks -- for test instances */ 173 public void stop() { 174 mContext.unregisterReceiver(mReceiver); 175 } 176 177 @Override 178 public void add(DropBoxManager.Entry entry) { 179 File temp = null; 180 OutputStream output = null; 181 final String tag = entry.getTag(); 182 try { 183 int flags = entry.getFlags(); 184 if ((flags & DropBoxManager.IS_EMPTY) != 0) throw new IllegalArgumentException(); 185 186 init(); 187 if (!isTagEnabled(tag)) return; 188 long max = trimToFit(); 189 long lastTrim = System.currentTimeMillis(); 190 191 byte[] buffer = new byte[mBlockSize]; 192 InputStream input = entry.getInputStream(); 193 194 // First, accumulate up to one block worth of data in memory before 195 // deciding whether to compress the data or not. 196 197 int read = 0; 198 while (read < buffer.length) { 199 int n = input.read(buffer, read, buffer.length - read); 200 if (n <= 0) break; 201 read += n; 202 } 203 204 // If we have at least one block, compress it -- otherwise, just write 205 // the data in uncompressed form. 206 207 temp = new File(mDropBoxDir, "drop" + Thread.currentThread().getId() + ".tmp"); 208 int bufferSize = mBlockSize; 209 if (bufferSize > 4096) bufferSize = 4096; 210 if (bufferSize < 512) bufferSize = 512; 211 FileOutputStream foutput = new FileOutputStream(temp); 212 output = new BufferedOutputStream(foutput, bufferSize); 213 if (read == buffer.length && ((flags & DropBoxManager.IS_GZIPPED) == 0)) { 214 output = new GZIPOutputStream(output); 215 flags = flags | DropBoxManager.IS_GZIPPED; 216 } 217 218 do { 219 output.write(buffer, 0, read); 220 221 long now = System.currentTimeMillis(); 222 if (now - lastTrim > 30 * 1000) { 223 max = trimToFit(); // In case data dribbles in slowly 224 lastTrim = now; 225 } 226 227 read = input.read(buffer); 228 if (read <= 0) { 229 FileUtils.sync(foutput); 230 output.close(); // Get a final size measurement 231 output = null; 232 } else { 233 output.flush(); // So the size measurement is pseudo-reasonable 234 } 235 236 long len = temp.length(); 237 if (len > max) { 238 Slog.w(TAG, "Dropping: " + tag + " (" + temp.length() + " > " + max + " bytes)"); 239 temp.delete(); 240 temp = null; // Pass temp = null to createEntry() to leave a tombstone 241 break; 242 } 243 } while (read > 0); 244 245 long time = createEntry(temp, tag, flags); 246 temp = null; 247 248 final Intent dropboxIntent = new Intent(DropBoxManager.ACTION_DROPBOX_ENTRY_ADDED); 249 dropboxIntent.putExtra(DropBoxManager.EXTRA_TAG, tag); 250 dropboxIntent.putExtra(DropBoxManager.EXTRA_TIME, time); 251 if (!mBooted) { 252 dropboxIntent.addFlags(Intent.FLAG_RECEIVER_REGISTERED_ONLY); 253 } 254 // Call sendBroadcast after returning from this call to avoid deadlock. In particular 255 // the caller may be holding the WindowManagerService lock but sendBroadcast requires a 256 // lock in ActivityManagerService. ActivityManagerService has been caught holding that 257 // very lock while waiting for the WindowManagerService lock. 258 mHandler.sendMessage(mHandler.obtainMessage(MSG_SEND_BROADCAST, dropboxIntent)); 259 } catch (IOException e) { 260 Slog.e(TAG, "Can't write: " + tag, e); 261 } finally { 262 try { if (output != null) output.close(); } catch (IOException e) {} 263 entry.close(); 264 if (temp != null) temp.delete(); 265 } 266 } 267 268 public boolean isTagEnabled(String tag) { 269 final long token = Binder.clearCallingIdentity(); 270 try { 271 return !"disabled".equals(Settings.Global.getString( 272 mContentResolver, Settings.Global.DROPBOX_TAG_PREFIX + tag)); 273 } finally { 274 Binder.restoreCallingIdentity(token); 275 } 276 } 277 278 public synchronized DropBoxManager.Entry getNextEntry(String tag, long millis) { 279 if (mContext.checkCallingOrSelfPermission(android.Manifest.permission.READ_LOGS) 280 != PackageManager.PERMISSION_GRANTED) { 281 throw new SecurityException("READ_LOGS permission required"); 282 } 283 284 try { 285 init(); 286 } catch (IOException e) { 287 Slog.e(TAG, "Can't init", e); 288 return null; 289 } 290 291 FileList list = tag == null ? mAllFiles : mFilesByTag.get(tag); 292 if (list == null) return null; 293 294 for (EntryFile entry : list.contents.tailSet(new EntryFile(millis + 1))) { 295 if (entry.tag == null) continue; 296 if ((entry.flags & DropBoxManager.IS_EMPTY) != 0) { 297 return new DropBoxManager.Entry(entry.tag, entry.timestampMillis); 298 } 299 try { 300 return new DropBoxManager.Entry( 301 entry.tag, entry.timestampMillis, entry.file, entry.flags); 302 } catch (IOException e) { 303 Slog.e(TAG, "Can't read: " + entry.file, e); 304 // Continue to next file 305 } 306 } 307 308 return null; 309 } 310 311 public synchronized void dump(FileDescriptor fd, PrintWriter pw, String[] args) { 312 if (mContext.checkCallingOrSelfPermission(android.Manifest.permission.DUMP) 313 != PackageManager.PERMISSION_GRANTED) { 314 pw.println("Permission Denial: Can't dump DropBoxManagerService"); 315 return; 316 } 317 318 try { 319 init(); 320 } catch (IOException e) { 321 pw.println("Can't initialize: " + e); 322 Slog.e(TAG, "Can't init", e); 323 return; 324 } 325 326 if (PROFILE_DUMP) Debug.startMethodTracing("/data/trace/dropbox.dump"); 327 328 StringBuilder out = new StringBuilder(); 329 boolean doPrint = false, doFile = false; 330 ArrayList<String> searchArgs = new ArrayList<String>(); 331 for (int i = 0; args != null && i < args.length; i++) { 332 if (args[i].equals("-p") || args[i].equals("--print")) { 333 doPrint = true; 334 } else if (args[i].equals("-f") || args[i].equals("--file")) { 335 doFile = true; 336 } else if (args[i].startsWith("-")) { 337 out.append("Unknown argument: ").append(args[i]).append("\n"); 338 } else { 339 searchArgs.add(args[i]); 340 } 341 } 342 343 out.append("Drop box contents: ").append(mAllFiles.contents.size()).append(" entries\n"); 344 345 if (!searchArgs.isEmpty()) { 346 out.append("Searching for:"); 347 for (String a : searchArgs) out.append(" ").append(a); 348 out.append("\n"); 349 } 350 351 int numFound = 0, numArgs = searchArgs.size(); 352 Time time = new Time(); 353 out.append("\n"); 354 for (EntryFile entry : mAllFiles.contents) { 355 time.set(entry.timestampMillis); 356 String date = time.format("%Y-%m-%d %H:%M:%S"); 357 boolean match = true; 358 for (int i = 0; i < numArgs && match; i++) { 359 String arg = searchArgs.get(i); 360 match = (date.contains(arg) || arg.equals(entry.tag)); 361 } 362 if (!match) continue; 363 364 numFound++; 365 if (doPrint) out.append("========================================\n"); 366 out.append(date).append(" ").append(entry.tag == null ? "(no tag)" : entry.tag); 367 if (entry.file == null) { 368 out.append(" (no file)\n"); 369 continue; 370 } else if ((entry.flags & DropBoxManager.IS_EMPTY) != 0) { 371 out.append(" (contents lost)\n"); 372 continue; 373 } else { 374 out.append(" ("); 375 if ((entry.flags & DropBoxManager.IS_GZIPPED) != 0) out.append("compressed "); 376 out.append((entry.flags & DropBoxManager.IS_TEXT) != 0 ? "text" : "data"); 377 out.append(", ").append(entry.file.length()).append(" bytes)\n"); 378 } 379 380 if (doFile || (doPrint && (entry.flags & DropBoxManager.IS_TEXT) == 0)) { 381 if (!doPrint) out.append(" "); 382 out.append(entry.file.getPath()).append("\n"); 383 } 384 385 if ((entry.flags & DropBoxManager.IS_TEXT) != 0 && (doPrint || !doFile)) { 386 DropBoxManager.Entry dbe = null; 387 InputStreamReader isr = null; 388 try { 389 dbe = new DropBoxManager.Entry( 390 entry.tag, entry.timestampMillis, entry.file, entry.flags); 391 392 if (doPrint) { 393 isr = new InputStreamReader(dbe.getInputStream()); 394 char[] buf = new char[4096]; 395 boolean newline = false; 396 for (;;) { 397 int n = isr.read(buf); 398 if (n <= 0) break; 399 out.append(buf, 0, n); 400 newline = (buf[n - 1] == '\n'); 401 402 // Flush periodically when printing to avoid out-of-memory. 403 if (out.length() > 65536) { 404 pw.write(out.toString()); 405 out.setLength(0); 406 } 407 } 408 if (!newline) out.append("\n"); 409 } else { 410 String text = dbe.getText(70); 411 out.append(" "); 412 if (text == null) { 413 out.append("[null]"); 414 } else { 415 boolean truncated = (text.length() == 70); 416 out.append(text.trim().replace('\n', '/')); 417 if (truncated) out.append(" ..."); 418 } 419 out.append("\n"); 420 } 421 } catch (IOException e) { 422 out.append("*** ").append(e.toString()).append("\n"); 423 Slog.e(TAG, "Can't read: " + entry.file, e); 424 } finally { 425 if (dbe != null) dbe.close(); 426 if (isr != null) { 427 try { 428 isr.close(); 429 } catch (IOException unused) { 430 } 431 } 432 } 433 } 434 435 if (doPrint) out.append("\n"); 436 } 437 438 if (numFound == 0) out.append("(No entries found.)\n"); 439 440 if (args == null || args.length == 0) { 441 if (!doPrint) out.append("\n"); 442 out.append("Usage: dumpsys dropbox [--print|--file] [YYYY-mm-dd] [HH:MM:SS] [tag]\n"); 443 } 444 445 pw.write(out.toString()); 446 if (PROFILE_DUMP) Debug.stopMethodTracing(); 447 } 448 449 /////////////////////////////////////////////////////////////////////////// 450 451 /** Chronologically sorted list of {@link #EntryFile} */ 452 private static final class FileList implements Comparable<FileList> { 453 public int blocks = 0; 454 public final TreeSet<EntryFile> contents = new TreeSet<EntryFile>(); 455 456 /** Sorts bigger FileList instances before smaller ones. */ 457 public final int compareTo(FileList o) { 458 if (blocks != o.blocks) return o.blocks - blocks; 459 if (this == o) return 0; 460 if (hashCode() < o.hashCode()) return -1; 461 if (hashCode() > o.hashCode()) return 1; 462 return 0; 463 } 464 } 465 466 /** Metadata describing an on-disk log file. */ 467 private static final class EntryFile implements Comparable<EntryFile> { 468 public final String tag; 469 public final long timestampMillis; 470 public final int flags; 471 public final File file; 472 public final int blocks; 473 474 /** Sorts earlier EntryFile instances before later ones. */ 475 public final int compareTo(EntryFile o) { 476 if (timestampMillis < o.timestampMillis) return -1; 477 if (timestampMillis > o.timestampMillis) return 1; 478 if (file != null && o.file != null) return file.compareTo(o.file); 479 if (o.file != null) return -1; 480 if (file != null) return 1; 481 if (this == o) return 0; 482 if (hashCode() < o.hashCode()) return -1; 483 if (hashCode() > o.hashCode()) return 1; 484 return 0; 485 } 486 487 /** 488 * Moves an existing temporary file to a new log filename. 489 * @param temp file to rename 490 * @param dir to store file in 491 * @param tag to use for new log file name 492 * @param timestampMillis of log entry 493 * @param flags for the entry data 494 * @param blockSize to use for space accounting 495 * @throws IOException if the file can't be moved 496 */ 497 public EntryFile(File temp, File dir, String tag,long timestampMillis, 498 int flags, int blockSize) throws IOException { 499 if ((flags & DropBoxManager.IS_EMPTY) != 0) throw new IllegalArgumentException(); 500 501 this.tag = tag; 502 this.timestampMillis = timestampMillis; 503 this.flags = flags; 504 this.file = new File(dir, Uri.encode(tag) + "@" + timestampMillis + 505 ((flags & DropBoxManager.IS_TEXT) != 0 ? ".txt" : ".dat") + 506 ((flags & DropBoxManager.IS_GZIPPED) != 0 ? ".gz" : "")); 507 508 if (!temp.renameTo(this.file)) { 509 throw new IOException("Can't rename " + temp + " to " + this.file); 510 } 511 this.blocks = (int) ((this.file.length() + blockSize - 1) / blockSize); 512 } 513 514 /** 515 * Creates a zero-length tombstone for a file whose contents were lost. 516 * @param dir to store file in 517 * @param tag to use for new log file name 518 * @param timestampMillis of log entry 519 * @throws IOException if the file can't be created. 520 */ 521 public EntryFile(File dir, String tag, long timestampMillis) throws IOException { 522 this.tag = tag; 523 this.timestampMillis = timestampMillis; 524 this.flags = DropBoxManager.IS_EMPTY; 525 this.file = new File(dir, Uri.encode(tag) + "@" + timestampMillis + ".lost"); 526 this.blocks = 0; 527 new FileOutputStream(this.file).close(); 528 } 529 530 /** 531 * Extracts metadata from an existing on-disk log filename. 532 * @param file name of existing log file 533 * @param blockSize to use for space accounting 534 */ 535 public EntryFile(File file, int blockSize) { 536 this.file = file; 537 this.blocks = (int) ((this.file.length() + blockSize - 1) / blockSize); 538 539 String name = file.getName(); 540 int at = name.lastIndexOf('@'); 541 if (at < 0) { 542 this.tag = null; 543 this.timestampMillis = 0; 544 this.flags = DropBoxManager.IS_EMPTY; 545 return; 546 } 547 548 int flags = 0; 549 this.tag = Uri.decode(name.substring(0, at)); 550 if (name.endsWith(".gz")) { 551 flags |= DropBoxManager.IS_GZIPPED; 552 name = name.substring(0, name.length() - 3); 553 } 554 if (name.endsWith(".lost")) { 555 flags |= DropBoxManager.IS_EMPTY; 556 name = name.substring(at + 1, name.length() - 5); 557 } else if (name.endsWith(".txt")) { 558 flags |= DropBoxManager.IS_TEXT; 559 name = name.substring(at + 1, name.length() - 4); 560 } else if (name.endsWith(".dat")) { 561 name = name.substring(at + 1, name.length() - 4); 562 } else { 563 this.flags = DropBoxManager.IS_EMPTY; 564 this.timestampMillis = 0; 565 return; 566 } 567 this.flags = flags; 568 569 long millis; 570 try { millis = Long.valueOf(name); } catch (NumberFormatException e) { millis = 0; } 571 this.timestampMillis = millis; 572 } 573 574 /** 575 * Creates a EntryFile object with only a timestamp for comparison purposes. 576 * @param timestampMillis to compare with. 577 */ 578 public EntryFile(long millis) { 579 this.tag = null; 580 this.timestampMillis = millis; 581 this.flags = DropBoxManager.IS_EMPTY; 582 this.file = null; 583 this.blocks = 0; 584 } 585 } 586 587 /////////////////////////////////////////////////////////////////////////// 588 589 /** If never run before, scans disk contents to build in-memory tracking data. */ 590 private synchronized void init() throws IOException { 591 if (mStatFs == null) { 592 if (!mDropBoxDir.isDirectory() && !mDropBoxDir.mkdirs()) { 593 throw new IOException("Can't mkdir: " + mDropBoxDir); 594 } 595 try { 596 mStatFs = new StatFs(mDropBoxDir.getPath()); 597 mBlockSize = mStatFs.getBlockSize(); 598 } catch (IllegalArgumentException e) { // StatFs throws this on error 599 throw new IOException("Can't statfs: " + mDropBoxDir); 600 } 601 } 602 603 if (mAllFiles == null) { 604 File[] files = mDropBoxDir.listFiles(); 605 if (files == null) throw new IOException("Can't list files: " + mDropBoxDir); 606 607 mAllFiles = new FileList(); 608 mFilesByTag = new HashMap<String, FileList>(); 609 610 // Scan pre-existing files. 611 for (File file : files) { 612 if (file.getName().endsWith(".tmp")) { 613 Slog.i(TAG, "Cleaning temp file: " + file); 614 file.delete(); 615 continue; 616 } 617 618 EntryFile entry = new EntryFile(file, mBlockSize); 619 if (entry.tag == null) { 620 Slog.w(TAG, "Unrecognized file: " + file); 621 continue; 622 } else if (entry.timestampMillis == 0) { 623 Slog.w(TAG, "Invalid filename: " + file); 624 file.delete(); 625 continue; 626 } 627 628 enrollEntry(entry); 629 } 630 } 631 } 632 633 /** Adds a disk log file to in-memory tracking for accounting and enumeration. */ 634 private synchronized void enrollEntry(EntryFile entry) { 635 mAllFiles.contents.add(entry); 636 mAllFiles.blocks += entry.blocks; 637 638 // mFilesByTag is used for trimming, so don't list empty files. 639 // (Zero-length/lost files are trimmed by date from mAllFiles.) 640 641 if (entry.tag != null && entry.file != null && entry.blocks > 0) { 642 FileList tagFiles = mFilesByTag.get(entry.tag); 643 if (tagFiles == null) { 644 tagFiles = new FileList(); 645 mFilesByTag.put(entry.tag, tagFiles); 646 } 647 tagFiles.contents.add(entry); 648 tagFiles.blocks += entry.blocks; 649 } 650 } 651 652 /** Moves a temporary file to a final log filename and enrolls it. */ 653 private synchronized long createEntry(File temp, String tag, int flags) throws IOException { 654 long t = System.currentTimeMillis(); 655 656 // Require each entry to have a unique timestamp; if there are entries 657 // >10sec in the future (due to clock skew), drag them back to avoid 658 // keeping them around forever. 659 660 SortedSet<EntryFile> tail = mAllFiles.contents.tailSet(new EntryFile(t + 10000)); 661 EntryFile[] future = null; 662 if (!tail.isEmpty()) { 663 future = tail.toArray(new EntryFile[tail.size()]); 664 tail.clear(); // Remove from mAllFiles 665 } 666 667 if (!mAllFiles.contents.isEmpty()) { 668 t = Math.max(t, mAllFiles.contents.last().timestampMillis + 1); 669 } 670 671 if (future != null) { 672 for (EntryFile late : future) { 673 mAllFiles.blocks -= late.blocks; 674 FileList tagFiles = mFilesByTag.get(late.tag); 675 if (tagFiles != null && tagFiles.contents.remove(late)) { 676 tagFiles.blocks -= late.blocks; 677 } 678 if ((late.flags & DropBoxManager.IS_EMPTY) == 0) { 679 enrollEntry(new EntryFile( 680 late.file, mDropBoxDir, late.tag, t++, late.flags, mBlockSize)); 681 } else { 682 enrollEntry(new EntryFile(mDropBoxDir, late.tag, t++)); 683 } 684 } 685 } 686 687 if (temp == null) { 688 enrollEntry(new EntryFile(mDropBoxDir, tag, t)); 689 } else { 690 enrollEntry(new EntryFile(temp, mDropBoxDir, tag, t, flags, mBlockSize)); 691 } 692 return t; 693 } 694 695 /** 696 * Trims the files on disk to make sure they aren't using too much space. 697 * @return the overall quota for storage (in bytes) 698 */ 699 private synchronized long trimToFit() { 700 // Expunge aged items (including tombstones marking deleted data). 701 702 int ageSeconds = Settings.Global.getInt(mContentResolver, 703 Settings.Global.DROPBOX_AGE_SECONDS, DEFAULT_AGE_SECONDS); 704 int maxFiles = Settings.Global.getInt(mContentResolver, 705 Settings.Global.DROPBOX_MAX_FILES, DEFAULT_MAX_FILES); 706 long cutoffMillis = System.currentTimeMillis() - ageSeconds * 1000; 707 while (!mAllFiles.contents.isEmpty()) { 708 EntryFile entry = mAllFiles.contents.first(); 709 if (entry.timestampMillis > cutoffMillis && mAllFiles.contents.size() < maxFiles) break; 710 711 FileList tag = mFilesByTag.get(entry.tag); 712 if (tag != null && tag.contents.remove(entry)) tag.blocks -= entry.blocks; 713 if (mAllFiles.contents.remove(entry)) mAllFiles.blocks -= entry.blocks; 714 if (entry.file != null) entry.file.delete(); 715 } 716 717 // Compute overall quota (a fraction of available free space) in blocks. 718 // The quota changes dynamically based on the amount of free space; 719 // that way when lots of data is available we can use it, but we'll get 720 // out of the way if storage starts getting tight. 721 722 long uptimeMillis = SystemClock.uptimeMillis(); 723 if (uptimeMillis > mCachedQuotaUptimeMillis + QUOTA_RESCAN_MILLIS) { 724 int quotaPercent = Settings.Global.getInt(mContentResolver, 725 Settings.Global.DROPBOX_QUOTA_PERCENT, DEFAULT_QUOTA_PERCENT); 726 int reservePercent = Settings.Global.getInt(mContentResolver, 727 Settings.Global.DROPBOX_RESERVE_PERCENT, DEFAULT_RESERVE_PERCENT); 728 int quotaKb = Settings.Global.getInt(mContentResolver, 729 Settings.Global.DROPBOX_QUOTA_KB, DEFAULT_QUOTA_KB); 730 731 mStatFs.restat(mDropBoxDir.getPath()); 732 int available = mStatFs.getAvailableBlocks(); 733 int nonreserved = available - mStatFs.getBlockCount() * reservePercent / 100; 734 int maximum = quotaKb * 1024 / mBlockSize; 735 mCachedQuotaBlocks = Math.min(maximum, Math.max(0, nonreserved * quotaPercent / 100)); 736 mCachedQuotaUptimeMillis = uptimeMillis; 737 } 738 739 // If we're using too much space, delete old items to make room. 740 // 741 // We trim each tag independently (this is why we keep per-tag lists). 742 // Space is "fairly" shared between tags -- they are all squeezed 743 // equally until enough space is reclaimed. 744 // 745 // A single circular buffer (a la logcat) would be simpler, but this 746 // way we can handle fat/bursty data (like 1MB+ bugreports, 300KB+ 747 // kernel crash dumps, and 100KB+ ANR reports) without swamping small, 748 // well-behaved data streams (event statistics, profile data, etc). 749 // 750 // Deleted files are replaced with zero-length tombstones to mark what 751 // was lost. Tombstones are expunged by age (see above). 752 753 if (mAllFiles.blocks > mCachedQuotaBlocks) { 754 // Find a fair share amount of space to limit each tag 755 int unsqueezed = mAllFiles.blocks, squeezed = 0; 756 TreeSet<FileList> tags = new TreeSet<FileList>(mFilesByTag.values()); 757 for (FileList tag : tags) { 758 if (squeezed > 0 && tag.blocks <= (mCachedQuotaBlocks - unsqueezed) / squeezed) { 759 break; 760 } 761 unsqueezed -= tag.blocks; 762 squeezed++; 763 } 764 int tagQuota = (mCachedQuotaBlocks - unsqueezed) / squeezed; 765 766 // Remove old items from each tag until it meets the per-tag quota. 767 for (FileList tag : tags) { 768 if (mAllFiles.blocks < mCachedQuotaBlocks) break; 769 while (tag.blocks > tagQuota && !tag.contents.isEmpty()) { 770 EntryFile entry = tag.contents.first(); 771 if (tag.contents.remove(entry)) tag.blocks -= entry.blocks; 772 if (mAllFiles.contents.remove(entry)) mAllFiles.blocks -= entry.blocks; 773 774 try { 775 if (entry.file != null) entry.file.delete(); 776 enrollEntry(new EntryFile(mDropBoxDir, entry.tag, entry.timestampMillis)); 777 } catch (IOException e) { 778 Slog.e(TAG, "Can't write tombstone file", e); 779 } 780 } 781 } 782 } 783 784 return mCachedQuotaBlocks * mBlockSize; 785 } 786 } 787
