core/java/com/android/server/BootReceiver.java - platform/frameworks/base - Git at Google

 /*
  * Copyright (C) 2009 The Android Open Source Project
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  *      http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */

 package com.android.server;

 import android.content.BroadcastReceiver;
 import android.content.Context;
 import android.content.Intent;
 import android.content.pm.IPackageManager;
 import android.os.Build;
 import android.os.DropBoxManager;
 import android.os.Environment;
 import android.os.FileObserver;
 import android.os.FileUtils;
 import android.os.RecoverySystem;
 import android.os.RemoteException;
 import android.os.ServiceManager;
 import android.os.SystemProperties;
 import android.os.storage.StorageManager;
 import android.provider.Downloads;
 import android.util.AtomicFile;
 import android.util.Slog;
 import android.util.Xml;

 import com.android.internal.util.FastXmlSerializer;
 import com.android.internal.util.XmlUtils;

 import java.io.File;
 import java.io.FileInputStream;
 import java.io.FileOutputStream;
 import java.io.IOException;
 import java.io.FileNotFoundException;
 import java.nio.charset.StandardCharsets;
 import java.util.HashMap;
 import java.util.Iterator;

 import org.xmlpull.v1.XmlPullParser;
 import org.xmlpull.v1.XmlPullParserException;
 import org.xmlpull.v1.XmlSerializer;

 /**
  * Performs a number of miscellaneous, non-system-critical actions
  * after the system has finished booting.
  */
 public class BootReceiver extends BroadcastReceiver {
     private static final String TAG = "BootReceiver";

     // Maximum size of a logged event (files get truncated if they're longer).
     // Give userdebug builds a larger max to capture extra debug, esp. for last_kmsg.
     private static final int LOG_SIZE =
         SystemProperties.getInt("ro.debuggable", 0) == 1 ? 98304 : 65536;

     private static final File TOMBSTONE_DIR = new File("/data/tombstones");

     // The pre-froyo package and class of the system updater, which
     // ran in the system process.  We need to remove its packages here
     // in order to clean up after a pre-froyo-to-froyo update.
     private static final String OLD_UPDATER_PACKAGE =
         "com.google.android.systemupdater";
     private static final String OLD_UPDATER_CLASS =
         "com.google.android.systemupdater.SystemUpdateReceiver";

     // Keep a reference to the observer so the finalizer doesn't disable it.
     private static FileObserver sTombstoneObserver = null;

     private static final String LOG_FILES_FILE = "log-files.xml";
     private static final AtomicFile sFile = new AtomicFile(new File(
             Environment.getDataSystemDirectory(), LOG_FILES_FILE));
     private static final String LAST_HEADER_FILE = "last-header.txt";
     private static final File lastHeaderFile = new File(
             Environment.getDataSystemDirectory(), LAST_HEADER_FILE);

     @Override
     public void onReceive(final Context context, Intent intent) {
         // Log boot events in the background to avoid blocking the main thread with I/O
         new Thread() {
             @Override
             public void run() {
                 try {
                     logBootEvents(context);
                 } catch (Exception e) {
                     Slog.e(TAG, "Can't log boot events", e);
                 }
                 try {
                     boolean onlyCore = false;
                     try {
                         onlyCore = IPackageManager.Stub.asInterface(ServiceManager.getService(
                                 "package")).isOnlyCoreApps();
                     } catch (RemoteException e) {
                     }
                     if (!onlyCore) {
                         removeOldUpdatePackages(context);
                     }
                 } catch (Exception e) {
                     Slog.e(TAG, "Can't remove old update packages", e);
                 }

             }
         }.start();
     }

     private void removeOldUpdatePackages(Context context) {
         Downloads.removeAllDownloadsByPackage(context, OLD_UPDATER_PACKAGE, OLD_UPDATER_CLASS);
     }

     private String getPreviousBootHeaders() {
         try {
             return FileUtils.readTextFile(lastHeaderFile, 0, null);
         } catch (IOException e) {
             Slog.e(TAG, "Error reading " + lastHeaderFile, e);
             return null;
         }
     }

     private String getCurrentBootHeaders() throws IOException {
         return new StringBuilder(512)
             .append("Build: ").append(Build.FINGERPRINT).append("\n")
             .append("Hardware: ").append(Build.BOARD).append("\n")
             .append("Revision: ")
             .append(SystemProperties.get("ro.revision", "")).append("\n")
             .append("Bootloader: ").append(Build.BOOTLOADER).append("\n")
             .append("Radio: ").append(Build.RADIO).append("\n")
             .append("Kernel: ")
             .append(FileUtils.readTextFile(new File("/proc/version"), 1024, "...\n"))
             .append("\n").toString();
     }


     private String getBootHeadersToLogAndUpdate() throws IOException {
         final String oldHeaders = getPreviousBootHeaders();
         final String newHeaders = getCurrentBootHeaders();

         try {
             FileUtils.stringToFile(lastHeaderFile, newHeaders);
         } catch (IOException e) {
             Slog.e(TAG, "Error writing " + lastHeaderFile, e);
         }

         if (oldHeaders == null) {
             // If we failed to read the old headers, use the current headers
             // but note this in the headers so we know
             return "isPrevious: false\n" + newHeaders;
         }

         return "isPrevious: true\n" + oldHeaders;
     }

     private void logBootEvents(Context ctx) throws IOException {
         final DropBoxManager db = (DropBoxManager) ctx.getSystemService(Context.DROPBOX_SERVICE);
         final String headers = getBootHeadersToLogAndUpdate();
         final String bootReason = SystemProperties.get("ro.boot.bootreason", null);

         String recovery = RecoverySystem.handleAftermath(ctx);
         if (recovery != null && db != null) {
             db.addText("SYSTEM_RECOVERY_LOG", headers + recovery);
         }

         String lastKmsgFooter = "";
         if (bootReason != null) {
             lastKmsgFooter = new StringBuilder(512)
                 .append("\n")
                 .append("Boot info:\n")
                 .append("Last boot reason: ").append(bootReason).append("\n")
                 .toString();
         }

         HashMap<String, Long> timestamps = readTimestamps();

         if (SystemProperties.getLong("ro.runtime.firstboot", 0) == 0) {
             if (StorageManager.inCryptKeeperBounce()) {
                 // Encrypted, first boot to get PIN/pattern/password so data is tmpfs
                 // Don't set ro.runtime.firstboot so that we will do this again
                 // when data is properly mounted
             } else {
                 String now = Long.toString(System.currentTimeMillis());
                 SystemProperties.set("ro.runtime.firstboot", now);
             }
             if (db != null) db.addText("SYSTEM_BOOT", headers);

             // Negative sizes mean to take the *tail* of the file (see FileUtils.readTextFile())
             addFileWithFootersToDropBox(db, timestamps, headers, lastKmsgFooter,
                     "/proc/last_kmsg", -LOG_SIZE, "SYSTEM_LAST_KMSG");
             addFileWithFootersToDropBox(db, timestamps, headers, lastKmsgFooter,
                     "/sys/fs/pstore/console-ramoops", -LOG_SIZE, "SYSTEM_LAST_KMSG");
             addFileToDropBox(db, timestamps, headers, "/cache/recovery/log", -LOG_SIZE,
                     "SYSTEM_RECOVERY_LOG");
             addFileToDropBox(db, timestamps, headers, "/cache/recovery/last_kmsg",
                     -LOG_SIZE, "SYSTEM_RECOVERY_KMSG");
             addAuditErrorsToDropBox(db, timestamps, headers, -LOG_SIZE, "SYSTEM_AUDIT");
             addFsckErrorsToDropBox(db, timestamps, headers, -LOG_SIZE, "SYSTEM_FSCK");
         } else {
             if (db != null) db.addText("SYSTEM_RESTART", headers);
         }

         // Scan existing tombstones (in case any new ones appeared)
         File[] tombstoneFiles = TOMBSTONE_DIR.listFiles();
         for (int i = 0; tombstoneFiles != null && i < tombstoneFiles.length; i++) {
             if (tombstoneFiles[i].isFile()) {
                 addFileToDropBox(db, timestamps, headers, tombstoneFiles[i].getPath(),
                         LOG_SIZE, "SYSTEM_TOMBSTONE");
             }
         }

         writeTimestamps(timestamps);

         // Start watching for new tombstone files; will record them as they occur.
         // This gets registered with the singleton file observer thread.
         sTombstoneObserver = new FileObserver(TOMBSTONE_DIR.getPath(), FileObserver.CLOSE_WRITE) {
             @Override
             public void onEvent(int event, String path) {
                 HashMap<String, Long> timestamps = readTimestamps();
                 try {
                     File file = new File(TOMBSTONE_DIR, path);
                     if (file.isFile()) {
                         addFileToDropBox(db, timestamps, headers, file.getPath(), LOG_SIZE,
                                 "SYSTEM_TOMBSTONE");
                     }
                 } catch (IOException e) {
                     Slog.e(TAG, "Can't log tombstone", e);
                 }
                 writeTimestamps(timestamps);
             }
         };

         sTombstoneObserver.startWatching();
     }

     private static void addFileToDropBox(
             DropBoxManager db, HashMap<String, Long> timestamps,
             String headers, String filename, int maxSize, String tag) throws IOException {
         addFileWithFootersToDropBox(db, timestamps, headers, "", filename, maxSize, tag);
     }

     private static void addFileWithFootersToDropBox(
             DropBoxManager db, HashMap<String, Long> timestamps,
             String headers, String footers, String filename, int maxSize,
             String tag) throws IOException {
         if (db == null || !db.isTagEnabled(tag)) return;  // Logging disabled

         File file = new File(filename);
         long fileTime = file.lastModified();
         if (fileTime <= 0) return;  // File does not exist

         if (timestamps.containsKey(filename) && timestamps.get(filename) == fileTime) {
             return;  // Already logged this particular file
         }

         timestamps.put(filename, fileTime);

         Slog.i(TAG, "Copying " + filename + " to DropBox (" + tag + ")");
         db.addText(tag, headers + FileUtils.readTextFile(file, maxSize, "[[TRUNCATED]]\n") +
                 footers);
     }

     private static void addAuditErrorsToDropBox(DropBoxManager db,
             HashMap<String, Long> timestamps, String headers, int maxSize, String tag)
             throws IOException {
         if (db == null || !db.isTagEnabled(tag)) return;  // Logging disabled
         Slog.i(TAG, "Copying audit failures to DropBox");

         File file = new File("/proc/last_kmsg");
         long fileTime = file.lastModified();
         if (fileTime <= 0) {
             file = new File("/sys/fs/pstore/console-ramoops");
             fileTime = file.lastModified();
         }

         if (fileTime <= 0) return;  // File does not exist

         if (timestamps.containsKey(tag) && timestamps.get(tag) == fileTime) {
             return;  // Already logged this particular file
         }

         timestamps.put(tag, fileTime);

         String log = FileUtils.readTextFile(file, maxSize, "[[TRUNCATED]]\n");
         StringBuilder sb = new StringBuilder();
         for (String line : log.split("\n")) {
             if (line.contains("audit")) {
                 sb.append(line + "\n");
             }
         }
         Slog.i(TAG, "Copied " + sb.toString().length() + " worth of audits to DropBox");
         db.addText(tag, headers + sb.toString());
     }

     private static void addFsckErrorsToDropBox(DropBoxManager db,
             HashMap<String, Long> timestamps, String headers, int maxSize, String tag)
             throws IOException {
         boolean upload_needed = false;
         if (db == null || !db.isTagEnabled(tag)) return;  // Logging disabled
         Slog.i(TAG, "Checking for fsck errors");

         File file = new File("/dev/fscklogs/log");
         long fileTime = file.lastModified();
         if (fileTime <= 0) return;  // File does not exist

         String log = FileUtils.readTextFile(file, maxSize, "[[TRUNCATED]]\n");
         StringBuilder sb = new StringBuilder();
         for (String line : log.split("\n")) {
             if (line.contains("FILE SYSTEM WAS MODIFIED")) {
                 upload_needed = true;
                 break;
             }
         }

         if (upload_needed) {
             addFileToDropBox(db, timestamps, headers, "/dev/fscklogs/log", maxSize, tag);
         }

         // Remove the file so we don't re-upload if the runtime restarts.
         file.delete();
     }

     private static HashMap<String, Long> readTimestamps() {
         synchronized (sFile) {
             HashMap<String, Long> timestamps = new HashMap<String, Long>();
             boolean success = false;
             try (final FileInputStream stream = sFile.openRead()) {
                 XmlPullParser parser = Xml.newPullParser();
                 parser.setInput(stream, StandardCharsets.UTF_8.name());

                 int type;
                 while ((type = parser.next()) != XmlPullParser.START_TAG
                         && type != XmlPullParser.END_DOCUMENT) {
                     ;
                 }

                 if (type != XmlPullParser.START_TAG) {
                     throw new IllegalStateException("no start tag found");
                 }

                 int outerDepth = parser.getDepth();  // Skip the outer <log-files> tag.
                 while ((type = parser.next()) != XmlPullParser.END_DOCUMENT
                         && (type != XmlPullParser.END_TAG || parser.getDepth() > outerDepth)) {
                     if (type == XmlPullParser.END_TAG || type == XmlPullParser.TEXT) {
                         continue;
                     }

                     String tagName = parser.getName();
                     if (tagName.equals("log")) {
                         final String filename = parser.getAttributeValue(null, "filename");
                         final long timestamp = Long.valueOf(parser.getAttributeValue(
                                     null, "timestamp"));
                         timestamps.put(filename, timestamp);
                     } else {
                         Slog.w(TAG, "Unknown tag: " + parser.getName());
                         XmlUtils.skipCurrentTag(parser);
                     }
                 }
                 success = true;
             } catch (FileNotFoundException e) {
                 Slog.i(TAG, "No existing last log timestamp file " + sFile.getBaseFile() +
                         "; starting empty");
             } catch (IOException e) {
                 Slog.w(TAG, "Failed parsing " + e);
             } catch (IllegalStateException e) {
                 Slog.w(TAG, "Failed parsing " + e);
             } catch (NullPointerException e) {
                 Slog.w(TAG, "Failed parsing " + e);
             } catch (XmlPullParserException e) {
                 Slog.w(TAG, "Failed parsing " + e);
             } finally {
                 if (!success) {
                     timestamps.clear();
                 }
             }
             return timestamps;
         }
     }

     private void writeTimestamps(HashMap<String, Long> timestamps) {
         synchronized (sFile) {
             final FileOutputStream stream;
             try {
                 stream = sFile.startWrite();
             } catch (IOException e) {
                 Slog.w(TAG, "Failed to write timestamp file: " + e);
                 return;
             }

             try {
                 XmlSerializer out = new FastXmlSerializer();
                 out.setOutput(stream, StandardCharsets.UTF_8.name());
                 out.startDocument(null, true);
                 out.startTag(null, "log-files");

                 Iterator<String> itor = timestamps.keySet().iterator();
                 while (itor.hasNext()) {
                     String filename = itor.next();
                     out.startTag(null, "log");
                     out.attribute(null, "filename", filename);
                     out.attribute(null, "timestamp", timestamps.get(filename).toString());
                     out.endTag(null, "log");
                 }

                 out.endTag(null, "log-files");
                 out.endDocument();

                 sFile.finishWrite(stream);
             } catch (IOException e) {
                 Slog.w(TAG, "Failed to write timestamp file, using the backup: " + e);
                 sFile.failWrite(stream);
             }
         }
     }
 }
	/*
	* Copyright (C) 2009 The Android Open Source Project
	*
	* Licensed under the Apache License, Version 2.0 (the "License");
	* you may not use this file except in compliance with the License.
	* You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/

	package com.android.server;

	import android.content.BroadcastReceiver;
	import android.content.Context;
	import android.content.Intent;
	import android.content.pm.IPackageManager;
	import android.os.Build;
	import android.os.DropBoxManager;
	import android.os.Environment;
	import android.os.FileObserver;
	import android.os.FileUtils;
	import android.os.RecoverySystem;
	import android.os.RemoteException;
	import android.os.ServiceManager;
	import android.os.SystemProperties;
	import android.os.storage.StorageManager;
	import android.provider.Downloads;
	import android.util.AtomicFile;
	import android.util.Slog;
	import android.util.Xml;

	import com.android.internal.util.FastXmlSerializer;
	import com.android.internal.util.XmlUtils;

	import java.io.File;
	import java.io.FileInputStream;
	import java.io.FileOutputStream;
	import java.io.IOException;
	import java.io.FileNotFoundException;
	import java.nio.charset.StandardCharsets;
	import java.util.HashMap;
	import java.util.Iterator;

	import org.xmlpull.v1.XmlPullParser;
	import org.xmlpull.v1.XmlPullParserException;
	import org.xmlpull.v1.XmlSerializer;

	/**
	* Performs a number of miscellaneous, non-system-critical actions
	* after the system has finished booting.
	*/
	public class BootReceiver extends BroadcastReceiver {
	private static final String TAG = "BootReceiver";

	// Maximum size of a logged event (files get truncated if they're longer).
	// Give userdebug builds a larger max to capture extra debug, esp. for last_kmsg.
	private static final int LOG_SIZE =
	SystemProperties.getInt("ro.debuggable", 0) == 1 ? 98304 : 65536;

	private static final File TOMBSTONE_DIR = new File("/data/tombstones");

	// The pre-froyo package and class of the system updater, which
	// ran in the system process. We need to remove its packages here
	// in order to clean up after a pre-froyo-to-froyo update.
	private static final String OLD_UPDATER_PACKAGE =
	"com.google.android.systemupdater";
	private static final String OLD_UPDATER_CLASS =
	"com.google.android.systemupdater.SystemUpdateReceiver";

	// Keep a reference to the observer so the finalizer doesn't disable it.
	private static FileObserver sTombstoneObserver = null;

	private static final String LOG_FILES_FILE = "log-files.xml";
	private static final AtomicFile sFile = new AtomicFile(new File(
	Environment.getDataSystemDirectory(), LOG_FILES_FILE));
	private static final String LAST_HEADER_FILE = "last-header.txt";
	private static final File lastHeaderFile = new File(
	Environment.getDataSystemDirectory(), LAST_HEADER_FILE);

	@Override
	public void onReceive(final Context context, Intent intent) {
	// Log boot events in the background to avoid blocking the main thread with I/O
	new Thread() {
	@Override
	public void run() {
	try {
	logBootEvents(context);
	} catch (Exception e) {
	Slog.e(TAG, "Can't log boot events", e);
	}
	try {
	boolean onlyCore = false;
	try {
	onlyCore = IPackageManager.Stub.asInterface(ServiceManager.getService(
	"package")).isOnlyCoreApps();
	} catch (RemoteException e) {
	}
	if (!onlyCore) {
	removeOldUpdatePackages(context);
	}
	} catch (Exception e) {
	Slog.e(TAG, "Can't remove old update packages", e);
	}

	}
	}.start();
	}

	private void removeOldUpdatePackages(Context context) {
	Downloads.removeAllDownloadsByPackage(context, OLD_UPDATER_PACKAGE, OLD_UPDATER_CLASS);
	}

	private String getPreviousBootHeaders() {
	try {
	return FileUtils.readTextFile(lastHeaderFile, 0, null);
	} catch (IOException e) {
	Slog.e(TAG, "Error reading " + lastHeaderFile, e);
	return null;
	}
	}

	private String getCurrentBootHeaders() throws IOException {
	return new StringBuilder(512)
	.append("Build: ").append(Build.FINGERPRINT).append("\n")
	.append("Hardware: ").append(Build.BOARD).append("\n")
	.append("Revision: ")
	.append(SystemProperties.get("ro.revision", "")).append("\n")
	.append("Bootloader: ").append(Build.BOOTLOADER).append("\n")
	.append("Radio: ").append(Build.RADIO).append("\n")
	.append("Kernel: ")
	.append(FileUtils.readTextFile(new File("/proc/version"), 1024, "...\n"))
	.append("\n").toString();
	}


	private String getBootHeadersToLogAndUpdate() throws IOException {
	final String oldHeaders = getPreviousBootHeaders();
	final String newHeaders = getCurrentBootHeaders();

	try {
	FileUtils.stringToFile(lastHeaderFile, newHeaders);
	} catch (IOException e) {
	Slog.e(TAG, "Error writing " + lastHeaderFile, e);
	}

	if (oldHeaders == null) {
	// If we failed to read the old headers, use the current headers
	// but note this in the headers so we know
	return "isPrevious: false\n" + newHeaders;
	}

	return "isPrevious: true\n" + oldHeaders;
	}

	private void logBootEvents(Context ctx) throws IOException {
	final DropBoxManager db = (DropBoxManager) ctx.getSystemService(Context.DROPBOX_SERVICE);
	final String headers = getBootHeadersToLogAndUpdate();
	final String bootReason = SystemProperties.get("ro.boot.bootreason", null);

	String recovery = RecoverySystem.handleAftermath(ctx);
	if (recovery != null && db != null) {
	db.addText("SYSTEM_RECOVERY_LOG", headers + recovery);
	}

	String lastKmsgFooter = "";
	if (bootReason != null) {
	lastKmsgFooter = new StringBuilder(512)
	.append("\n")
	.append("Boot info:\n")
	.append("Last boot reason: ").append(bootReason).append("\n")
	.toString();
	}

	HashMap<String, Long> timestamps = readTimestamps();

	if (SystemProperties.getLong("ro.runtime.firstboot", 0) == 0) {
	if (StorageManager.inCryptKeeperBounce()) {
	// Encrypted, first boot to get PIN/pattern/password so data is tmpfs
	// Don't set ro.runtime.firstboot so that we will do this again
	// when data is properly mounted
	} else {
	String now = Long.toString(System.currentTimeMillis());
	SystemProperties.set("ro.runtime.firstboot", now);
	}
	if (db != null) db.addText("SYSTEM_BOOT", headers);

	// Negative sizes mean to take the tail of the file (see FileUtils.readTextFile())
	addFileWithFootersToDropBox(db, timestamps, headers, lastKmsgFooter,
	"/proc/last_kmsg", -LOG_SIZE, "SYSTEM_LAST_KMSG");
	addFileWithFootersToDropBox(db, timestamps, headers, lastKmsgFooter,
	"/sys/fs/pstore/console-ramoops", -LOG_SIZE, "SYSTEM_LAST_KMSG");
	addFileToDropBox(db, timestamps, headers, "/cache/recovery/log", -LOG_SIZE,
	"SYSTEM_RECOVERY_LOG");
	addFileToDropBox(db, timestamps, headers, "/cache/recovery/last_kmsg",
	-LOG_SIZE, "SYSTEM_RECOVERY_KMSG");
	addAuditErrorsToDropBox(db, timestamps, headers, -LOG_SIZE, "SYSTEM_AUDIT");
	addFsckErrorsToDropBox(db, timestamps, headers, -LOG_SIZE, "SYSTEM_FSCK");
	} else {
	if (db != null) db.addText("SYSTEM_RESTART", headers);
	}

	// Scan existing tombstones (in case any new ones appeared)
	File[] tombstoneFiles = TOMBSTONE_DIR.listFiles();
	for (int i = 0; tombstoneFiles != null && i < tombstoneFiles.length; i++) {
	if (tombstoneFiles[i].isFile()) {
	addFileToDropBox(db, timestamps, headers, tombstoneFiles[i].getPath(),
	LOG_SIZE, "SYSTEM_TOMBSTONE");
	}
	}

	writeTimestamps(timestamps);

	// Start watching for new tombstone files; will record them as they occur.
	// This gets registered with the singleton file observer thread.
	sTombstoneObserver = new FileObserver(TOMBSTONE_DIR.getPath(), FileObserver.CLOSE_WRITE) {
	@Override
	public void onEvent(int event, String path) {
	HashMap<String, Long> timestamps = readTimestamps();
	try {
	File file = new File(TOMBSTONE_DIR, path);
	if (file.isFile()) {
	addFileToDropBox(db, timestamps, headers, file.getPath(), LOG_SIZE,
	"SYSTEM_TOMBSTONE");
	}
	} catch (IOException e) {
	Slog.e(TAG, "Can't log tombstone", e);
	}
	writeTimestamps(timestamps);
	}
	};

	sTombstoneObserver.startWatching();
	}

	private static void addFileToDropBox(
	DropBoxManager db, HashMap<String, Long> timestamps,
	String headers, String filename, int maxSize, String tag) throws IOException {
	addFileWithFootersToDropBox(db, timestamps, headers, "", filename, maxSize, tag);
	}

	private static void addFileWithFootersToDropBox(
	DropBoxManager db, HashMap<String, Long> timestamps,
	String headers, String footers, String filename, int maxSize,
	String tag) throws IOException {
	if (db == null \|\| !db.isTagEnabled(tag)) return; // Logging disabled

	File file = new File(filename);
	long fileTime = file.lastModified();
	if (fileTime <= 0) return; // File does not exist

	if (timestamps.containsKey(filename) && timestamps.get(filename) == fileTime) {
	return; // Already logged this particular file
	}

	timestamps.put(filename, fileTime);

	Slog.i(TAG, "Copying " + filename + " to DropBox (" + tag + ")");
	db.addText(tag, headers + FileUtils.readTextFile(file, maxSize, "[[TRUNCATED]]\n") +
	footers);
	}

	private static void addAuditErrorsToDropBox(DropBoxManager db,
	HashMap<String, Long> timestamps, String headers, int maxSize, String tag)
	throws IOException {
	if (db == null \|\| !db.isTagEnabled(tag)) return; // Logging disabled
	Slog.i(TAG, "Copying audit failures to DropBox");

	File file = new File("/proc/last_kmsg");
	long fileTime = file.lastModified();
	if (fileTime <= 0) {
	file = new File("/sys/fs/pstore/console-ramoops");
	fileTime = file.lastModified();
	}

	if (fileTime <= 0) return; // File does not exist

	if (timestamps.containsKey(tag) && timestamps.get(tag) == fileTime) {
	return; // Already logged this particular file
	}

	timestamps.put(tag, fileTime);

	String log = FileUtils.readTextFile(file, maxSize, "[[TRUNCATED]]\n");
	StringBuilder sb = new StringBuilder();
	for (String line : log.split("\n")) {
	if (line.contains("audit")) {
	sb.append(line + "\n");
	}
	}
	Slog.i(TAG, "Copied " + sb.toString().length() + " worth of audits to DropBox");
	db.addText(tag, headers + sb.toString());
	}

	private static void addFsckErrorsToDropBox(DropBoxManager db,
	HashMap<String, Long> timestamps, String headers, int maxSize, String tag)
	throws IOException {
	boolean upload_needed = false;
	if (db == null \|\| !db.isTagEnabled(tag)) return; // Logging disabled
	Slog.i(TAG, "Checking for fsck errors");

	File file = new File("/dev/fscklogs/log");
	long fileTime = file.lastModified();
	if (fileTime <= 0) return; // File does not exist

	String log = FileUtils.readTextFile(file, maxSize, "[[TRUNCATED]]\n");
	StringBuilder sb = new StringBuilder();
	for (String line : log.split("\n")) {
	if (line.contains("FILE SYSTEM WAS MODIFIED")) {
	upload_needed = true;
	break;
	}
	}

	if (upload_needed) {
	addFileToDropBox(db, timestamps, headers, "/dev/fscklogs/log", maxSize, tag);
	}

	// Remove the file so we don't re-upload if the runtime restarts.
	file.delete();
	}

	private static HashMap<String, Long> readTimestamps() {
	synchronized (sFile) {
	HashMap<String, Long> timestamps = new HashMap<String, Long>();
	boolean success = false;
	try (final FileInputStream stream = sFile.openRead()) {
	XmlPullParser parser = Xml.newPullParser();
	parser.setInput(stream, StandardCharsets.UTF_8.name());

	int type;
	while ((type = parser.next()) != XmlPullParser.START_TAG
	&& type != XmlPullParser.END_DOCUMENT) {
	;
	}

	if (type != XmlPullParser.START_TAG) {
	throw new IllegalStateException("no start tag found");
	}

	int outerDepth = parser.getDepth(); // Skip the outer <log-files> tag.
	while ((type = parser.next()) != XmlPullParser.END_DOCUMENT
	&& (type != XmlPullParser.END_TAG \|\| parser.getDepth() > outerDepth)) {
	if (type == XmlPullParser.END_TAG \|\| type == XmlPullParser.TEXT) {
	continue;
	}

	String tagName = parser.getName();
	if (tagName.equals("log")) {
	final String filename = parser.getAttributeValue(null, "filename");
	final long timestamp = Long.valueOf(parser.getAttributeValue(
	null, "timestamp"));
	timestamps.put(filename, timestamp);
	} else {
	Slog.w(TAG, "Unknown tag: " + parser.getName());
	XmlUtils.skipCurrentTag(parser);
	}
	}
	success = true;
	} catch (FileNotFoundException e) {
	Slog.i(TAG, "No existing last log timestamp file " + sFile.getBaseFile() +
	"; starting empty");
	} catch (IOException e) {
	Slog.w(TAG, "Failed parsing " + e);
	} catch (IllegalStateException e) {
	Slog.w(TAG, "Failed parsing " + e);
	} catch (NullPointerException e) {
	Slog.w(TAG, "Failed parsing " + e);
	} catch (XmlPullParserException e) {
	Slog.w(TAG, "Failed parsing " + e);
	} finally {
	if (!success) {
	timestamps.clear();
	}
	}
	return timestamps;
	}
	}

	private void writeTimestamps(HashMap<String, Long> timestamps) {
	synchronized (sFile) {
	final FileOutputStream stream;
	try {
	stream = sFile.startWrite();
	} catch (IOException e) {
	Slog.w(TAG, "Failed to write timestamp file: " + e);
	return;
	}

	try {
	XmlSerializer out = new FastXmlSerializer();
	out.setOutput(stream, StandardCharsets.UTF_8.name());
	out.startDocument(null, true);
	out.startTag(null, "log-files");

	Iterator<String> itor = timestamps.keySet().iterator();
	while (itor.hasNext()) {
	String filename = itor.next();
	out.startTag(null, "log");
	out.attribute(null, "filename", filename);
	out.attribute(null, "timestamp", timestamps.get(filename).toString());
	out.endTag(null, "log");
	}

	out.endTag(null, "log-files");
	out.endDocument();

	sFile.finishWrite(stream);
	} catch (IOException e) {
	Slog.w(TAG, "Failed to write timestamp file, using the backup: " + e);
	sFile.failWrite(stream);
	}
	}
	}
	}