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.Context;
21 import android.content.Intent;
22 import android.content.pm.IPackageManager;
23 import android.os.Build;
24 import android.os.DropBoxManager;
25 import android.os.Environment;
26 import android.os.FileObserver;
27 import android.os.FileUtils;
28 import android.os.RecoverySystem;
29 import android.os.RemoteException;
30 import android.os.ServiceManager;
31 import android.os.SystemProperties;
32 import android.os.storage.StorageManager;
33 import android.provider.Downloads;
34 import android.util.AtomicFile;
35 import android.util.Slog;
36 import android.util.Xml;
37 
38 import com.android.internal.annotations.VisibleForTesting;
39 import com.android.internal.logging.MetricsLogger;
40 import com.android.internal.util.ArrayUtils;
41 import com.android.internal.util.FastXmlSerializer;
42 import com.android.internal.util.XmlUtils;
43 
44 import java.io.File;
45 import java.io.FileInputStream;
46 import java.io.FileOutputStream;
47 import java.io.IOException;
48 import java.io.FileNotFoundException;
49 import java.nio.charset.StandardCharsets;
50 import java.util.HashMap;
51 import java.util.Iterator;
52 import java.util.regex.Matcher;
53 import java.util.regex.Pattern;
54 
55 import org.xmlpull.v1.XmlPullParser;
56 import org.xmlpull.v1.XmlPullParserException;
57 import org.xmlpull.v1.XmlSerializer;
58 
59 /**
60  * Performs a number of miscellaneous, non-system-critical actions
61  * after the system has finished booting.
62  */
63 public class BootReceiver extends BroadcastReceiver {
64     private static final String TAG = "BootReceiver";
65 
66     // Maximum size of a logged event (files get truncated if they're longer).
67     // Give userdebug builds a larger max to capture extra debug, esp. for last_kmsg.
68     private static final int LOG_SIZE =
69         SystemProperties.getInt("ro.debuggable", 0) == 1 ? 98304 : 65536;
70 
71     private static final File TOMBSTONE_DIR = new File("/data/tombstones");
72 
73     // The pre-froyo package and class of the system updater, which
74     // ran in the system process.  We need to remove its packages here
75     // in order to clean up after a pre-froyo-to-froyo update.
76     private static final String OLD_UPDATER_PACKAGE =
77         "com.google.android.systemupdater";
78     private static final String OLD_UPDATER_CLASS =
79         "com.google.android.systemupdater.SystemUpdateReceiver";
80 
81     // Keep a reference to the observer so the finalizer doesn't disable it.
82     private static FileObserver sTombstoneObserver = null;
83 
84     private static final String LOG_FILES_FILE = "log-files.xml";
85     private static final AtomicFile sFile = new AtomicFile(new File(
86             Environment.getDataSystemDirectory(), LOG_FILES_FILE));
87     private static final String LAST_HEADER_FILE = "last-header.txt";
88     private static final File lastHeaderFile = new File(
89             Environment.getDataSystemDirectory(), LAST_HEADER_FILE);
90 
91     // example: fs_stat,/dev/block/platform/soc/by-name/userdata,0x5
92     private static final String FS_STAT_PATTERN = "fs_stat,[^,]*/([^/,]+),(0x[0-9a-fA-F]+)";
93     private static final int FS_STAT_FS_FIXED = 0x400; // should match with fs_mgr.cpp:FsStatFlags
94     private static final String FSCK_PASS_PATTERN = "Pass ([1-9]E?):";
95     private static final String FSCK_TREE_OPTIMIZATION_PATTERN =
96             "Inode [0-9]+ extent tree.*could be shorter";
97     private static final String FSCK_FS_MODIFIED = "FILE SYSTEM WAS MODIFIED";
98     // ro.boottime.init.mount_all. + postfix for mount_all duration
99     private static final String[] MOUNT_DURATION_PROPS_POSTFIX =
100             new String[] { "early", "default", "late" };
101     // for reboot, fs shutdown time is recorded in last_kmsg.
102     private static final String[] LAST_KMSG_FILES =
103             new String[] { "/sys/fs/pstore/console-ramoops", "/proc/last_kmsg" };
104     // first: fs shutdown time in ms, second: umount status defined in init/reboot.h
105     private static final String LAST_SHUTDOWN_TIME_PATTERN =
106             "powerctl_shutdown_time_ms:([0-9]+):([0-9]+)";
107     private static final int UMOUNT_STATUS_NOT_AVAILABLE = 4; // should match with init/reboot.h
108 
109     @Override
onReceive(final Context context, Intent intent)110     public void onReceive(final Context context, Intent intent) {
111         // Log boot events in the background to avoid blocking the main thread with I/O
112         new Thread() {
113             @Override
114             public void run() {
115                 try {
116                     logBootEvents(context);
117                 } catch (Exception e) {
118                     Slog.e(TAG, "Can't log boot events", e);
119                 }
120                 try {
121                     boolean onlyCore = false;
122                     try {
123                         onlyCore = IPackageManager.Stub.asInterface(ServiceManager.getService(
124                                 "package")).isOnlyCoreApps();
125                     } catch (RemoteException e) {
126                     }
127                     if (!onlyCore) {
128                         removeOldUpdatePackages(context);
129                     }
130                 } catch (Exception e) {
131                     Slog.e(TAG, "Can't remove old update packages", e);
132                 }
133 
134             }
135         }.start();
136     }
137 
removeOldUpdatePackages(Context context)138     private void removeOldUpdatePackages(Context context) {
139         Downloads.removeAllDownloadsByPackage(context, OLD_UPDATER_PACKAGE, OLD_UPDATER_CLASS);
140     }
141 
getPreviousBootHeaders()142     private String getPreviousBootHeaders() {
143         try {
144             return FileUtils.readTextFile(lastHeaderFile, 0, null);
145         } catch (IOException e) {
146             Slog.e(TAG, "Error reading " + lastHeaderFile, e);
147             return null;
148         }
149     }
150 
getCurrentBootHeaders()151     private String getCurrentBootHeaders() throws IOException {
152         return new StringBuilder(512)
153             .append("Build: ").append(Build.FINGERPRINT).append("\n")
154             .append("Hardware: ").append(Build.BOARD).append("\n")
155             .append("Revision: ")
156             .append(SystemProperties.get("ro.revision", "")).append("\n")
157             .append("Bootloader: ").append(Build.BOOTLOADER).append("\n")
158             .append("Radio: ").append(Build.RADIO).append("\n")
159             .append("Kernel: ")
160             .append(FileUtils.readTextFile(new File("/proc/version"), 1024, "...\n"))
161             .append("\n").toString();
162     }
163 
164 
getBootHeadersToLogAndUpdate()165     private String getBootHeadersToLogAndUpdate() throws IOException {
166         final String oldHeaders = getPreviousBootHeaders();
167         final String newHeaders = getCurrentBootHeaders();
168 
169         try {
170             FileUtils.stringToFile(lastHeaderFile, newHeaders);
171         } catch (IOException e) {
172             Slog.e(TAG, "Error writing " + lastHeaderFile, e);
173         }
174 
175         if (oldHeaders == null) {
176             // If we failed to read the old headers, use the current headers
177             // but note this in the headers so we know
178             return "isPrevious: false\n" + newHeaders;
179         }
180 
181         return "isPrevious: true\n" + oldHeaders;
182     }
183 
logBootEvents(Context ctx)184     private void logBootEvents(Context ctx) throws IOException {
185         final DropBoxManager db = (DropBoxManager) ctx.getSystemService(Context.DROPBOX_SERVICE);
186         final String headers = getBootHeadersToLogAndUpdate();
187         final String bootReason = SystemProperties.get("ro.boot.bootreason", null);
188 
189         String recovery = RecoverySystem.handleAftermath(ctx);
190         if (recovery != null && db != null) {
191             db.addText("SYSTEM_RECOVERY_LOG", headers + recovery);
192         }
193 
194         String lastKmsgFooter = "";
195         if (bootReason != null) {
196             lastKmsgFooter = new StringBuilder(512)
197                 .append("\n")
198                 .append("Boot info:\n")
199                 .append("Last boot reason: ").append(bootReason).append("\n")
200                 .toString();
201         }
202 
203         HashMap<String, Long> timestamps = readTimestamps();
204 
205         if (SystemProperties.getLong("ro.runtime.firstboot", 0) == 0) {
206             if (StorageManager.inCryptKeeperBounce()) {
207                 // Encrypted, first boot to get PIN/pattern/password so data is tmpfs
208                 // Don't set ro.runtime.firstboot so that we will do this again
209                 // when data is properly mounted
210             } else {
211                 String now = Long.toString(System.currentTimeMillis());
212                 SystemProperties.set("ro.runtime.firstboot", now);
213             }
214             if (db != null) db.addText("SYSTEM_BOOT", headers);
215 
216             // Negative sizes mean to take the *tail* of the file (see FileUtils.readTextFile())
217             addFileWithFootersToDropBox(db, timestamps, headers, lastKmsgFooter,
218                     "/proc/last_kmsg", -LOG_SIZE, "SYSTEM_LAST_KMSG");
219             addFileWithFootersToDropBox(db, timestamps, headers, lastKmsgFooter,
220                     "/sys/fs/pstore/console-ramoops", -LOG_SIZE, "SYSTEM_LAST_KMSG");
221             addFileToDropBox(db, timestamps, headers, "/cache/recovery/log", -LOG_SIZE,
222                     "SYSTEM_RECOVERY_LOG");
223             addFileToDropBox(db, timestamps, headers, "/cache/recovery/last_kmsg",
224                     -LOG_SIZE, "SYSTEM_RECOVERY_KMSG");
225             addAuditErrorsToDropBox(db, timestamps, headers, -LOG_SIZE, "SYSTEM_AUDIT");
226         } else {
227             if (db != null) db.addText("SYSTEM_RESTART", headers);
228         }
229         // log always available fs_stat last so that logcat collecting tools can wait until
230         // fs_stat to get all file system metrics.
231         logFsShutdownTime();
232         logFsMountTime();
233         addFsckErrorsToDropBoxAndLogFsStat(db, timestamps, headers, -LOG_SIZE, "SYSTEM_FSCK");
234 
235         // Scan existing tombstones (in case any new ones appeared)
236         File[] tombstoneFiles = TOMBSTONE_DIR.listFiles();
237         for (int i = 0; tombstoneFiles != null && i < tombstoneFiles.length; i++) {
238             if (tombstoneFiles[i].isFile()) {
239                 addFileToDropBox(db, timestamps, headers, tombstoneFiles[i].getPath(),
240                         LOG_SIZE, "SYSTEM_TOMBSTONE");
241             }
242         }
243 
244         writeTimestamps(timestamps);
245 
246         // Start watching for new tombstone files; will record them as they occur.
247         // This gets registered with the singleton file observer thread.
248         sTombstoneObserver = new FileObserver(TOMBSTONE_DIR.getPath(), FileObserver.CLOSE_WRITE) {
249             @Override
250             public void onEvent(int event, String path) {
251                 HashMap<String, Long> timestamps = readTimestamps();
252                 try {
253                     File file = new File(TOMBSTONE_DIR, path);
254                     if (file.isFile()) {
255                         addFileToDropBox(db, timestamps, headers, file.getPath(), LOG_SIZE,
256                                 "SYSTEM_TOMBSTONE");
257                     }
258                 } catch (IOException e) {
259                     Slog.e(TAG, "Can't log tombstone", e);
260                 }
261                 writeTimestamps(timestamps);
262             }
263         };
264 
265         sTombstoneObserver.startWatching();
266     }
267 
addFileToDropBox( DropBoxManager db, HashMap<String, Long> timestamps, String headers, String filename, int maxSize, String tag)268     private static void addFileToDropBox(
269             DropBoxManager db, HashMap<String, Long> timestamps,
270             String headers, String filename, int maxSize, String tag) throws IOException {
271         addFileWithFootersToDropBox(db, timestamps, headers, "", filename, maxSize, tag);
272     }
273 
addFileWithFootersToDropBox( DropBoxManager db, HashMap<String, Long> timestamps, String headers, String footers, String filename, int maxSize, String tag)274     private static void addFileWithFootersToDropBox(
275             DropBoxManager db, HashMap<String, Long> timestamps,
276             String headers, String footers, String filename, int maxSize,
277             String tag) throws IOException {
278         if (db == null || !db.isTagEnabled(tag)) return;  // Logging disabled
279 
280         File file = new File(filename);
281         long fileTime = file.lastModified();
282         if (fileTime <= 0) return;  // File does not exist
283 
284         if (timestamps.containsKey(filename) && timestamps.get(filename) == fileTime) {
285             return;  // Already logged this particular file
286         }
287 
288         timestamps.put(filename, fileTime);
289 
290         Slog.i(TAG, "Copying " + filename + " to DropBox (" + tag + ")");
291         db.addText(tag, headers + FileUtils.readTextFile(file, maxSize, "[[TRUNCATED]]\n") +
292                 footers);
293     }
294 
addAuditErrorsToDropBox(DropBoxManager db, HashMap<String, Long> timestamps, String headers, int maxSize, String tag)295     private static void addAuditErrorsToDropBox(DropBoxManager db,
296             HashMap<String, Long> timestamps, String headers, int maxSize, String tag)
297             throws IOException {
298         if (db == null || !db.isTagEnabled(tag)) return;  // Logging disabled
299         Slog.i(TAG, "Copying audit failures to DropBox");
300 
301         File file = new File("/proc/last_kmsg");
302         long fileTime = file.lastModified();
303         if (fileTime <= 0) {
304             file = new File("/sys/fs/pstore/console-ramoops");
305             fileTime = file.lastModified();
306         }
307 
308         if (fileTime <= 0) return;  // File does not exist
309 
310         if (timestamps.containsKey(tag) && timestamps.get(tag) == fileTime) {
311             return;  // Already logged this particular file
312         }
313 
314         timestamps.put(tag, fileTime);
315 
316         String log = FileUtils.readTextFile(file, maxSize, "[[TRUNCATED]]\n");
317         StringBuilder sb = new StringBuilder();
318         for (String line : log.split("\n")) {
319             if (line.contains("audit")) {
320                 sb.append(line + "\n");
321             }
322         }
323         Slog.i(TAG, "Copied " + sb.toString().length() + " worth of audits to DropBox");
324         db.addText(tag, headers + sb.toString());
325     }
326 
addFsckErrorsToDropBoxAndLogFsStat(DropBoxManager db, HashMap<String, Long> timestamps, String headers, int maxSize, String tag)327     private static void addFsckErrorsToDropBoxAndLogFsStat(DropBoxManager db,
328             HashMap<String, Long> timestamps, String headers, int maxSize, String tag)
329             throws IOException {
330         boolean uploadEnabled = true;
331         if (db == null || !db.isTagEnabled(tag)) {
332             uploadEnabled = false;
333         }
334         boolean uploadNeeded = false;
335         Slog.i(TAG, "Checking for fsck errors");
336 
337         File file = new File("/dev/fscklogs/log");
338         long fileTime = file.lastModified();
339         if (fileTime <= 0) return;  // File does not exist
340 
341         String log = FileUtils.readTextFile(file, maxSize, "[[TRUNCATED]]\n");
342         Pattern pattern = Pattern.compile(FS_STAT_PATTERN);
343         String lines[] = log.split("\n");
344         int lineNumber = 0;
345         int lastFsStatLineNumber = 0;
346         for (String line : lines) { // should check all lines
347             if (line.contains(FSCK_FS_MODIFIED)) {
348                 uploadNeeded = true;
349             } else if (line.contains("fs_stat")){
350                 Matcher matcher = pattern.matcher(line);
351                 if (matcher.find()) {
352                     handleFsckFsStat(matcher, lines, lastFsStatLineNumber, lineNumber);
353                     lastFsStatLineNumber = lineNumber;
354                 } else {
355                     Slog.w(TAG, "cannot parse fs_stat:" + line);
356                 }
357             }
358             lineNumber++;
359         }
360 
361         if (uploadEnabled && uploadNeeded ) {
362             addFileToDropBox(db, timestamps, headers, "/dev/fscklogs/log", maxSize, tag);
363         }
364 
365         // Remove the file so we don't re-upload if the runtime restarts.
366         file.delete();
367     }
368 
logFsMountTime()369     private static void logFsMountTime() {
370         for (String propPostfix : MOUNT_DURATION_PROPS_POSTFIX) {
371             int duration = SystemProperties.getInt("ro.boottime.init.mount_all." + propPostfix, 0);
372             if (duration != 0) {
373                 MetricsLogger.histogram(null, "boot_mount_all_duration_" + propPostfix, duration);
374             }
375         }
376     }
377 
logFsShutdownTime()378     private static void logFsShutdownTime() {
379         File f = null;
380         for (String fileName : LAST_KMSG_FILES) {
381             File file = new File(fileName);
382             if (!file.exists()) continue;
383             f = file;
384             break;
385         }
386         if (f == null) { // no last_kmsg
387             return;
388         }
389 
390         final int maxReadSize = 16*1024;
391         // last_kmsg can be very big, so only parse the last part
392         String lines;
393         try {
394             lines = FileUtils.readTextFile(f, -maxReadSize, null);
395         } catch (IOException e) {
396             Slog.w(TAG, "cannot read last msg", e);
397             return;
398         }
399         Pattern pattern = Pattern.compile(LAST_SHUTDOWN_TIME_PATTERN, Pattern.MULTILINE);
400         Matcher matcher = pattern.matcher(lines);
401         if (matcher.find()) {
402             MetricsLogger.histogram(null, "boot_fs_shutdown_duration",
403                     Integer.parseInt(matcher.group(1)));
404             MetricsLogger.histogram(null, "boot_fs_shutdown_umount_stat",
405                     Integer.parseInt(matcher.group(2)));
406             Slog.i(TAG, "boot_fs_shutdown," + matcher.group(1) + "," + matcher.group(2));
407         } else { // not found
408             // This can happen when a device has too much kernel log after file system unmount
409             // ,exceeding maxReadSize. And having that much kernel logging can affect overall
410             // performance as well. So it is better to fix the kernel to reduce the amount of log.
411             MetricsLogger.histogram(null, "boot_fs_shutdown_umount_stat",
412                     UMOUNT_STATUS_NOT_AVAILABLE);
413             Slog.w(TAG, "boot_fs_shutdown, string not found");
414         }
415     }
416 
417     /**
418      * Fix fs_stat from e2fsck.
419      * For now, only handle the case of quota warning caused by tree optimization. Clear fs fix
420      * flag (=0x400) caused by that.
421      *
422      * @param partition partition name
423      * @param statOrg original stat reported from e2fsck log
424      * @param lines e2fsck logs broken down into lines
425      * @param startLineNumber start line to parse
426      * @param endLineNumber end line. exclusive.
427      * @return updated fs_stat. For tree optimization, will clear bit 0x400.
428      */
429     @VisibleForTesting
fixFsckFsStat(String partition, int statOrg, String[] lines, int startLineNumber, int endLineNumber)430     public static int fixFsckFsStat(String partition, int statOrg, String[] lines,
431             int startLineNumber, int endLineNumber) {
432         int stat = statOrg;
433         if ((stat & FS_STAT_FS_FIXED) != 0) {
434             // fs was fixed. should check if quota warning was caused by tree optimization.
435             // This is not a real fix but optimization, so should not be counted as a fs fix.
436             Pattern passPattern = Pattern.compile(FSCK_PASS_PATTERN);
437             Pattern treeOptPattern = Pattern.compile(FSCK_TREE_OPTIMIZATION_PATTERN);
438             String currentPass = "";
439             boolean foundTreeOptimization = false;
440             boolean foundQuotaFix = false;
441             boolean foundOtherFix = false;
442             String otherFixLine = null;
443             for (int i = startLineNumber; i < endLineNumber; i++) {
444                 String line = lines[i];
445                 if (line.contains(FSCK_FS_MODIFIED)) { // no need to parse above this
446                     break;
447                 } else if (line.startsWith("Pass ")) {
448                     Matcher matcher = passPattern.matcher(line);
449                     if (matcher.find()) {
450                         currentPass = matcher.group(1);
451                     }
452                 } else if (line.startsWith("Inode ")) {
453                     Matcher matcher = treeOptPattern.matcher(line);
454                     if (matcher.find() && currentPass.equals("1")) {
455                         foundTreeOptimization = true;
456                         Slog.i(TAG, "fs_stat, partition:" + partition + " found tree optimization:"
457                                 + line);
458                     } else {
459                         foundOtherFix = true;
460                         otherFixLine = line;
461                         break;
462                     }
463                 } else if (line.startsWith("[QUOTA WARNING]") && currentPass.equals("5")) {
464                     Slog.i(TAG, "fs_stat, partition:" + partition + " found quota warning:"
465                             + line);
466                     foundQuotaFix = true;
467                     if (!foundTreeOptimization) { // only quota warning, this is real fix.
468                         otherFixLine = line;
469                         break;
470                     }
471                 } else if (line.startsWith("Update quota info") && currentPass.equals("5")) {
472                     // follows "[QUOTA WARNING]", ignore
473                 } else {
474                     line = line.trim();
475                     // ignore empty msg or any msg before Pass 1
476                     if (!line.isEmpty() && !currentPass.isEmpty()) {
477                         foundOtherFix = true;
478                         otherFixLine = line;
479                         break;
480                     }
481                 }
482             }
483             if (!foundOtherFix && foundTreeOptimization && foundQuotaFix) {
484                 // not a real fix, so clear it.
485                 Slog.i(TAG, "fs_stat, partition:" + partition +
486                         " quota fix due to tree optimization");
487                 stat &= ~FS_STAT_FS_FIXED;
488             } else {
489                 if (otherFixLine != null) {
490                     Slog.i(TAG, "fs_stat, partition:" + partition + " fix:" + otherFixLine);
491                 }
492             }
493         }
494         return stat;
495     }
496 
handleFsckFsStat(Matcher match, String[] lines, int startLineNumber, int endLineNumber)497     private static void handleFsckFsStat(Matcher match, String[] lines, int startLineNumber,
498             int endLineNumber) {
499         String partition = match.group(1);
500         int stat;
501         try {
502             stat = Integer.decode(match.group(2));
503         } catch (NumberFormatException e) {
504             Slog.w(TAG, "cannot parse fs_stat: partition:" + partition + " stat:" + match.group(2));
505             return;
506         }
507         stat = fixFsckFsStat(partition, stat, lines, startLineNumber, endLineNumber);
508         MetricsLogger.histogram(null, "boot_fs_stat_" + partition, stat);
509         Slog.i(TAG, "fs_stat, partition:" + partition + " stat:0x" + Integer.toHexString(stat));
510     }
511 
readTimestamps()512     private static HashMap<String, Long> readTimestamps() {
513         synchronized (sFile) {
514             HashMap<String, Long> timestamps = new HashMap<String, Long>();
515             boolean success = false;
516             try (final FileInputStream stream = sFile.openRead()) {
517                 XmlPullParser parser = Xml.newPullParser();
518                 parser.setInput(stream, StandardCharsets.UTF_8.name());
519 
520                 int type;
521                 while ((type = parser.next()) != XmlPullParser.START_TAG
522                         && type != XmlPullParser.END_DOCUMENT) {
523                     ;
524                 }
525 
526                 if (type != XmlPullParser.START_TAG) {
527                     throw new IllegalStateException("no start tag found");
528                 }
529 
530                 int outerDepth = parser.getDepth();  // Skip the outer <log-files> tag.
531                 while ((type = parser.next()) != XmlPullParser.END_DOCUMENT
532                         && (type != XmlPullParser.END_TAG || parser.getDepth() > outerDepth)) {
533                     if (type == XmlPullParser.END_TAG || type == XmlPullParser.TEXT) {
534                         continue;
535                     }
536 
537                     String tagName = parser.getName();
538                     if (tagName.equals("log")) {
539                         final String filename = parser.getAttributeValue(null, "filename");
540                         final long timestamp = Long.valueOf(parser.getAttributeValue(
541                                     null, "timestamp"));
542                         timestamps.put(filename, timestamp);
543                     } else {
544                         Slog.w(TAG, "Unknown tag: " + parser.getName());
545                         XmlUtils.skipCurrentTag(parser);
546                     }
547                 }
548                 success = true;
549             } catch (FileNotFoundException e) {
550                 Slog.i(TAG, "No existing last log timestamp file " + sFile.getBaseFile() +
551                         "; starting empty");
552             } catch (IOException e) {
553                 Slog.w(TAG, "Failed parsing " + e);
554             } catch (IllegalStateException e) {
555                 Slog.w(TAG, "Failed parsing " + e);
556             } catch (NullPointerException e) {
557                 Slog.w(TAG, "Failed parsing " + e);
558             } catch (XmlPullParserException e) {
559                 Slog.w(TAG, "Failed parsing " + e);
560             } finally {
561                 if (!success) {
562                     timestamps.clear();
563                 }
564             }
565             return timestamps;
566         }
567     }
568 
writeTimestamps(HashMap<String, Long> timestamps)569     private void writeTimestamps(HashMap<String, Long> timestamps) {
570         synchronized (sFile) {
571             final FileOutputStream stream;
572             try {
573                 stream = sFile.startWrite();
574             } catch (IOException e) {
575                 Slog.w(TAG, "Failed to write timestamp file: " + e);
576                 return;
577             }
578 
579             try {
580                 XmlSerializer out = new FastXmlSerializer();
581                 out.setOutput(stream, StandardCharsets.UTF_8.name());
582                 out.startDocument(null, true);
583                 out.startTag(null, "log-files");
584 
585                 Iterator<String> itor = timestamps.keySet().iterator();
586                 while (itor.hasNext()) {
587                     String filename = itor.next();
588                     out.startTag(null, "log");
589                     out.attribute(null, "filename", filename);
590                     out.attribute(null, "timestamp", timestamps.get(filename).toString());
591                     out.endTag(null, "log");
592                 }
593 
594                 out.endTag(null, "log-files");
595                 out.endDocument();
596 
597                 sFile.finishWrite(stream);
598             } catch (IOException e) {
599                 Slog.w(TAG, "Failed to write timestamp file, using the backup: " + e);
600                 sFile.failWrite(stream);
601             }
602         }
603     }
604 }
605