Craig Mautner | 21d24a2 | 2014-04-23 11:45:37 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2014 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.am; |
| 18 | |
| 19 | import android.graphics.Bitmap; |
| 20 | import android.graphics.BitmapFactory; |
| 21 | import android.os.Debug; |
| 22 | import android.os.SystemClock; |
| 23 | import android.util.ArraySet; |
| 24 | import android.util.AtomicFile; |
| 25 | import android.util.Slog; |
| 26 | import android.util.Xml; |
| 27 | import com.android.internal.util.FastXmlSerializer; |
| 28 | import com.android.internal.util.XmlUtils; |
| 29 | import org.xmlpull.v1.XmlPullParser; |
| 30 | import org.xmlpull.v1.XmlPullParserException; |
| 31 | import org.xmlpull.v1.XmlSerializer; |
| 32 | |
| 33 | import java.io.BufferedReader; |
| 34 | import java.io.File; |
| 35 | import java.io.FileOutputStream; |
| 36 | import java.io.FileReader; |
| 37 | import java.io.IOException; |
| 38 | import java.io.StringWriter; |
| 39 | import java.util.ArrayList; |
| 40 | import java.util.Arrays; |
| 41 | import java.util.Comparator; |
| 42 | |
| 43 | public class TaskPersister { |
| 44 | static final String TAG = "TaskPersister"; |
| 45 | static final boolean DEBUG = false; |
| 46 | |
| 47 | /** When in slow mode don't write tasks out faster than this */ |
| 48 | private static final long INTER_TASK_DELAY_MS = 60000; |
| 49 | private static final long DEBUG_INTER_TASK_DELAY_MS = 5000; |
| 50 | |
| 51 | private static final String RECENTS_FILENAME = "_task"; |
| 52 | private static final String TASKS_DIRNAME = "recent_tasks"; |
| 53 | private static final String TASK_EXTENSION = ".xml"; |
| 54 | private static final String IMAGES_DIRNAME = "recent_images"; |
| 55 | private static final String IMAGE_EXTENSION = ".png"; |
| 56 | |
| 57 | private static final String TAG_TASK = "task"; |
| 58 | |
| 59 | private static File sImagesDir; |
| 60 | private static File sTasksDir; |
| 61 | |
| 62 | private final ActivityManagerService mService; |
| 63 | private final ActivityStackSupervisor mStackSupervisor; |
| 64 | |
| 65 | private boolean mRecentsChanged = false; |
| 66 | |
| 67 | private final LazyTaskWriterThread mLazyTaskWriterThread; |
| 68 | |
| 69 | TaskPersister(File systemDir, ActivityStackSupervisor stackSupervisor) { |
| 70 | sTasksDir = new File(systemDir, TASKS_DIRNAME); |
| 71 | if (!sTasksDir.exists()) { |
| 72 | if (!sTasksDir.mkdir()) { |
| 73 | Slog.e(TAG, "Failure creating tasks directory " + sTasksDir); |
| 74 | } |
| 75 | } |
| 76 | |
| 77 | sImagesDir = new File(systemDir, IMAGES_DIRNAME); |
| 78 | if (!sImagesDir.exists()) { |
| 79 | if (!sImagesDir.mkdir()) { |
| 80 | Slog.e(TAG, "Failure creating images directory " + sImagesDir); |
| 81 | } |
| 82 | } |
| 83 | |
| 84 | mStackSupervisor = stackSupervisor; |
| 85 | mService = stackSupervisor.mService; |
| 86 | |
| 87 | mLazyTaskWriterThread = new LazyTaskWriterThread("LazyTaskWriterThread"); |
| 88 | } |
| 89 | |
| 90 | void startPersisting() { |
| 91 | mLazyTaskWriterThread.start(); |
| 92 | } |
| 93 | |
| 94 | public void notify(TaskRecord task, boolean flush) { |
| 95 | if (DEBUG) Slog.d(TAG, "notify: task=" + task + " flush=" + flush + |
| 96 | " Callers=" + Debug.getCallers(4)); |
| 97 | if (task != null) { |
| 98 | task.needsPersisting = true; |
| 99 | } |
| 100 | synchronized (this) { |
| 101 | mLazyTaskWriterThread.mSlow = !flush; |
| 102 | mRecentsChanged = true; |
| 103 | notifyAll(); |
| 104 | } |
| 105 | } |
| 106 | |
| 107 | private StringWriter saveToXml(TaskRecord task) throws IOException, XmlPullParserException { |
| 108 | if (DEBUG) Slog.d(TAG, "saveToXml: task=" + task); |
| 109 | final XmlSerializer xmlSerializer = new FastXmlSerializer(); |
| 110 | StringWriter stringWriter = new StringWriter(); |
| 111 | xmlSerializer.setOutput(stringWriter); |
| 112 | |
| 113 | if (DEBUG) xmlSerializer.setFeature( |
| 114 | "http://xmlpull.org/v1/doc/features.html#indent-output", true); |
| 115 | |
| 116 | // save task |
| 117 | xmlSerializer.startDocument(null, true); |
| 118 | |
| 119 | xmlSerializer.startTag(null, TAG_TASK); |
| 120 | task.saveToXml(xmlSerializer); |
| 121 | xmlSerializer.endTag(null, TAG_TASK); |
| 122 | |
| 123 | xmlSerializer.endDocument(); |
| 124 | xmlSerializer.flush(); |
| 125 | |
| 126 | return stringWriter; |
| 127 | } |
| 128 | |
| 129 | static void saveImage(Bitmap image, String filename) throws IOException { |
| 130 | if (DEBUG) Slog.d(TAG, "saveImage: filename=" + filename); |
| 131 | FileOutputStream imageFile = null; |
| 132 | try { |
| 133 | imageFile = new FileOutputStream(new File(sImagesDir, filename + IMAGE_EXTENSION)); |
| 134 | image.compress(Bitmap.CompressFormat.PNG, 100, imageFile); |
| 135 | } catch (Exception e) { |
| 136 | Slog.e(TAG, "saveImage: unable to save " + filename, e); |
| 137 | } finally { |
| 138 | if (imageFile != null) { |
| 139 | imageFile.close(); |
| 140 | } |
| 141 | } |
| 142 | } |
| 143 | |
| 144 | ArrayList<TaskRecord> restoreTasksLocked() { |
| 145 | final ArrayList<TaskRecord> tasks = new ArrayList<TaskRecord>(); |
| 146 | ArraySet<Integer> recoveredTaskIds = new ArraySet<Integer>(); |
| 147 | |
| 148 | File[] recentFiles = sTasksDir.listFiles(); |
| 149 | if (recentFiles == null) { |
| 150 | Slog.e(TAG, "Unable to list files from " + sTasksDir); |
| 151 | return tasks; |
| 152 | } |
| 153 | |
| 154 | for (int taskNdx = 0; taskNdx < recentFiles.length; ++taskNdx) { |
| 155 | File taskFile = recentFiles[taskNdx]; |
| 156 | if (DEBUG) Slog.d(TAG, "restoreTasksLocked: taskFile=" + taskFile.getName()); |
| 157 | BufferedReader reader = null; |
| 158 | try { |
| 159 | reader = new BufferedReader(new FileReader(taskFile)); |
| 160 | final XmlPullParser in = Xml.newPullParser(); |
| 161 | in.setInput(reader); |
| 162 | |
| 163 | int event; |
| 164 | while (((event = in.next()) != XmlPullParser.END_DOCUMENT) && |
| 165 | event != XmlPullParser.END_TAG) { |
| 166 | final String name = in.getName(); |
| 167 | if (event == XmlPullParser.START_TAG) { |
| 168 | if (DEBUG) Slog.d(TAG, "restoreTasksLocked: START_TAG name=" + name); |
| 169 | if (TAG_TASK.equals(name)) { |
| 170 | final TaskRecord task = |
| 171 | TaskRecord.restoreFromXml(in, mStackSupervisor); |
| 172 | if (DEBUG) Slog.d(TAG, "restoreTasksLocked: restored task=" + task); |
| 173 | if (task != null) { |
| 174 | tasks.add(task); |
| 175 | final int taskId = task.taskId; |
| 176 | recoveredTaskIds.add(taskId); |
| 177 | mStackSupervisor.setNextTaskId(taskId); |
| 178 | } |
| 179 | } else { |
| 180 | Slog.e(TAG, "restoreTasksLocked Unknown xml event=" + event + " name=" |
| 181 | + name); |
| 182 | } |
| 183 | } |
| 184 | XmlUtils.skipCurrentTag(in); |
| 185 | } |
| 186 | } catch (IOException e) { |
| 187 | Slog.e(TAG, "Unable to parse " + taskFile + ". Error " + e); |
| 188 | } catch (XmlPullParserException e) { |
| 189 | Slog.e(TAG, "Unable to parse " + taskFile + ". Error " + e); |
| 190 | } finally { |
| 191 | if (reader != null) { |
| 192 | try { |
| 193 | reader.close(); |
| 194 | } catch (IOException e) { |
| 195 | } |
| 196 | } |
| 197 | } |
| 198 | } |
| 199 | |
| 200 | if (!DEBUG) { |
| 201 | removeObsoleteFiles(recoveredTaskIds); |
| 202 | } |
| 203 | |
| 204 | TaskRecord[] tasksArray = new TaskRecord[tasks.size()]; |
| 205 | tasks.toArray(tasksArray); |
| 206 | Arrays.sort(tasksArray, new Comparator<TaskRecord>() { |
| 207 | @Override |
| 208 | public int compare(TaskRecord lhs, TaskRecord rhs) { |
| 209 | final long diff = lhs.mLastTimeMoved - rhs.mLastTimeMoved; |
| 210 | if (diff < 0) { |
| 211 | return -1; |
| 212 | } else if (diff > 0) { |
| 213 | return +1; |
| 214 | } else { |
| 215 | return 0; |
| 216 | } |
| 217 | } |
| 218 | }); |
| 219 | |
| 220 | return new ArrayList<TaskRecord>(Arrays.asList(tasksArray)); |
| 221 | } |
| 222 | |
| 223 | private void removeObsoleteFiles(ArraySet<Integer> persistentTaskIds, File[] files) { |
| 224 | for (int fileNdx = 0; fileNdx < files.length; ++fileNdx) { |
| 225 | File file = files[fileNdx]; |
| 226 | String filename = file.getName(); |
| 227 | final int taskIdEnd = filename.indexOf('_') + 1; |
| 228 | if (taskIdEnd > 0) { |
| 229 | final int taskId; |
| 230 | try { |
| 231 | taskId = Integer.valueOf(filename.substring(0, taskIdEnd)); |
| 232 | } catch (Exception e) { |
| 233 | if (DEBUG) Slog.d(TAG, "removeObsoleteFile: Can't parse file=" + |
| 234 | file.getName()); |
| 235 | file.delete(); |
| 236 | continue; |
| 237 | } |
| 238 | if (!persistentTaskIds.contains(taskId)) { |
| 239 | if (DEBUG) Slog.d(TAG, "removeObsoleteFile: deleting file=" + file.getName()); |
| 240 | file.delete(); |
| 241 | } |
| 242 | } |
| 243 | } |
| 244 | } |
| 245 | |
| 246 | private void removeObsoleteFiles(ArraySet<Integer> persistentTaskIds) { |
| 247 | removeObsoleteFiles(persistentTaskIds, sTasksDir.listFiles()); |
| 248 | removeObsoleteFiles(persistentTaskIds, sImagesDir.listFiles()); |
| 249 | } |
| 250 | |
| 251 | static Bitmap restoreImage(String filename) { |
| 252 | if (DEBUG) Slog.d(TAG, "restoreImage: restoring " + filename); |
| 253 | return BitmapFactory.decodeFile(sImagesDir + File.separator + filename + IMAGE_EXTENSION); |
| 254 | } |
| 255 | |
| 256 | private class LazyTaskWriterThread extends Thread { |
| 257 | boolean mSlow = true; |
| 258 | |
| 259 | LazyTaskWriterThread(String name) { |
| 260 | super(name); |
| 261 | } |
| 262 | |
| 263 | @Override |
| 264 | public void run() { |
| 265 | ArraySet<Integer> persistentTaskIds = new ArraySet<Integer>(); |
| 266 | while (true) { |
| 267 | // If mSlow, then delay between each call to saveToXml(). |
| 268 | synchronized (TaskPersister.this) { |
| 269 | long now = SystemClock.uptimeMillis(); |
| 270 | final long releaseTime = |
| 271 | now + (DEBUG ? DEBUG_INTER_TASK_DELAY_MS: INTER_TASK_DELAY_MS); |
| 272 | while (mSlow && now < releaseTime) { |
| 273 | try { |
| 274 | if (DEBUG) Slog.d(TAG, "LazyTaskWriter: waiting " + |
| 275 | (releaseTime - now)); |
| 276 | TaskPersister.this.wait(releaseTime - now); |
| 277 | } catch (InterruptedException e) { |
| 278 | } |
| 279 | now = SystemClock.uptimeMillis(); |
| 280 | } |
| 281 | } |
| 282 | |
| 283 | StringWriter stringWriter = null; |
| 284 | TaskRecord task = null; |
| 285 | synchronized(mService) { |
| 286 | final ArrayList<TaskRecord> tasks = mService.mRecentTasks; |
| 287 | persistentTaskIds.clear(); |
| 288 | int taskNdx; |
| 289 | for (taskNdx = tasks.size() - 1; taskNdx >= 0; --taskNdx) { |
| 290 | task = tasks.get(taskNdx); |
| 291 | if (DEBUG) Slog.d(TAG, "LazyTaskWriter: task=" + task + " persistable=" + |
| 292 | task.isPersistable + " needsPersisting=" + task.needsPersisting); |
| 293 | if (task.isPersistable) { |
| 294 | persistentTaskIds.add(task.taskId); |
| 295 | |
| 296 | if (task.needsPersisting) { |
| 297 | try { |
| 298 | stringWriter = saveToXml(task); |
| 299 | break; |
| 300 | } catch (IOException e) { |
| 301 | } catch (XmlPullParserException e) { |
| 302 | } finally { |
| 303 | task.needsPersisting = false; |
| 304 | } |
| 305 | } |
| 306 | } |
| 307 | } |
| 308 | } |
| 309 | |
| 310 | if (stringWriter != null) { |
| 311 | // Write out xml file while not holding mService lock. |
| 312 | FileOutputStream file = null; |
| 313 | AtomicFile atomicFile = null; |
| 314 | try { |
| 315 | atomicFile = new AtomicFile(new File(sTasksDir, |
| 316 | String.valueOf(task.taskId) + RECENTS_FILENAME + TASK_EXTENSION)); |
| 317 | file = atomicFile.startWrite(); |
| 318 | file.write(stringWriter.toString().getBytes()); |
| 319 | file.write('\n'); |
| 320 | atomicFile.finishWrite(file); |
| 321 | } catch (IOException e) { |
| 322 | if (file != null) { |
| 323 | atomicFile.failWrite(file); |
| 324 | } |
| 325 | Slog.e(TAG, "Unable to open " + atomicFile + " for persisting. " + e); |
| 326 | } |
| 327 | } else { |
| 328 | // Made it through the entire list and didn't find anything new that needed |
| 329 | // persisting. |
| 330 | if (!DEBUG) { |
| 331 | removeObsoleteFiles(persistentTaskIds); |
| 332 | } |
| 333 | |
| 334 | // Wait here for someone to call setRecentsChanged(). |
| 335 | synchronized (TaskPersister.this) { |
| 336 | while (!mRecentsChanged) { |
| 337 | if (DEBUG) Slog.d(TAG, "LazyTaskWriter: Waiting."); |
| 338 | try { |
| 339 | TaskPersister.this.wait(); |
| 340 | } catch (InterruptedException e) { |
| 341 | } |
| 342 | } |
| 343 | mRecentsChanged = false; |
| 344 | if (DEBUG) Slog.d(TAG, "LazyTaskWriter: Awake"); |
| 345 | } |
| 346 | } |
| 347 | // Some recents file needs to be written. |
| 348 | } |
| 349 | } |
| 350 | } |
| 351 | } |