• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 /*
2  * Copyright (C) 2006 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.internal.os;
18 
19 import android.app.ActivityManager;
20 import android.app.ActivityThread;
21 import android.app.ApplicationErrorReport;
22 import android.app.IActivityManager;
23 import android.compat.annotation.UnsupportedAppUsage;
24 import android.content.type.DefaultMimeMapFactory;
25 import android.os.Build;
26 import android.os.DeadObjectException;
27 import android.os.IBinder;
28 import android.os.Process;
29 import android.os.SystemProperties;
30 import android.os.Trace;
31 import android.util.Log;
32 import android.util.Slog;
33 
34 import com.android.internal.logging.AndroidConfig;
35 import com.android.server.NetworkManagementSocketTagger;
36 
37 import dalvik.system.RuntimeHooks;
38 import dalvik.system.VMRuntime;
39 
40 import libcore.content.type.MimeMap;
41 
42 import java.lang.reflect.InvocationTargetException;
43 import java.lang.reflect.Method;
44 import java.lang.reflect.Modifier;
45 import java.util.Objects;
46 import java.util.logging.LogManager;
47 
48 /**
49  * Main entry point for runtime initialization.  Not for
50  * public consumption.
51  * @hide
52  */
53 public class RuntimeInit {
54     final static String TAG = "AndroidRuntime";
55     final static boolean DEBUG = false;
56 
57     /** true if commonInit() has been called */
58     @UnsupportedAppUsage
59     private static boolean initialized;
60 
61     @UnsupportedAppUsage
62     private static IBinder mApplicationObject;
63 
64     private static volatile boolean mCrashing = false;
65 
66     private static volatile ApplicationWtfHandler sDefaultApplicationWtfHandler;
67 
nativeFinishInit()68     private static final native void nativeFinishInit();
nativeSetExitWithoutCleanup(boolean exitWithoutCleanup)69     private static final native void nativeSetExitWithoutCleanup(boolean exitWithoutCleanup);
70 
Clog_e(String tag, String msg, Throwable tr)71     private static int Clog_e(String tag, String msg, Throwable tr) {
72         return Log.printlns(Log.LOG_ID_CRASH, Log.ERROR, tag, msg, tr);
73     }
74 
logUncaught(String threadName, String processName, int pid, Throwable e)75     public static void logUncaught(String threadName, String processName, int pid, Throwable e) {
76         StringBuilder message = new StringBuilder();
77         // The "FATAL EXCEPTION" string is still used on Android even though
78         // apps can set a custom UncaughtExceptionHandler that renders uncaught
79         // exceptions non-fatal.
80         message.append("FATAL EXCEPTION: ").append(threadName).append("\n");
81         if (processName != null) {
82             message.append("Process: ").append(processName).append(", ");
83         }
84         message.append("PID: ").append(pid);
85         Clog_e(TAG, message.toString(), e);
86     }
87 
88     /**
89      * Logs a message when a thread encounters an uncaught exception. By
90      * default, {@link KillApplicationHandler} will terminate this process later,
91      * but apps can override that behavior.
92      */
93     private static class LoggingHandler implements Thread.UncaughtExceptionHandler {
94         public volatile boolean mTriggered = false;
95 
96         @Override
uncaughtException(Thread t, Throwable e)97         public void uncaughtException(Thread t, Throwable e) {
98             mTriggered = true;
99 
100             // Don't re-enter if KillApplicationHandler has already run
101             if (mCrashing) return;
102 
103             // mApplicationObject is null for non-zygote java programs (e.g. "am")
104             // There are also apps running with the system UID. We don't want the
105             // first clause in either of these two cases, only for system_server.
106             if (mApplicationObject == null && (Process.SYSTEM_UID == Process.myUid())) {
107                 Clog_e(TAG, "*** FATAL EXCEPTION IN SYSTEM PROCESS: " + t.getName(), e);
108             } else {
109                 logUncaught(t.getName(), ActivityThread.currentProcessName(), Process.myPid(), e);
110             }
111         }
112     }
113 
114     /**
115      * Handle application death from an uncaught exception.  The framework
116      * catches these for the main threads, so this should only matter for
117      * threads created by applications. Before this method runs, the given
118      * instance of {@link LoggingHandler} should already have logged details
119      * (and if not it is run first).
120      */
121     private static class KillApplicationHandler implements Thread.UncaughtExceptionHandler {
122         private final LoggingHandler mLoggingHandler;
123 
124         /**
125          * Create a new KillApplicationHandler that follows the given LoggingHandler.
126          * If {@link #uncaughtException(Thread, Throwable) uncaughtException} is called
127          * on the created instance without {@code loggingHandler} having been triggered,
128          * {@link LoggingHandler#uncaughtException(Thread, Throwable)
129          * loggingHandler.uncaughtException} will be called first.
130          *
131          * @param loggingHandler the {@link LoggingHandler} expected to have run before
132          *     this instance's {@link #uncaughtException(Thread, Throwable) uncaughtException}
133          *     is being called.
134          */
KillApplicationHandler(LoggingHandler loggingHandler)135         public KillApplicationHandler(LoggingHandler loggingHandler) {
136             this.mLoggingHandler = Objects.requireNonNull(loggingHandler);
137         }
138 
139         @Override
uncaughtException(Thread t, Throwable e)140         public void uncaughtException(Thread t, Throwable e) {
141             try {
142                 ensureLogging(t, e);
143 
144                 // Don't re-enter -- avoid infinite loops if crash-reporting crashes.
145                 if (mCrashing) return;
146                 mCrashing = true;
147 
148                 // Try to end profiling. If a profiler is running at this point, and we kill the
149                 // process (below), the in-memory buffer will be lost. So try to stop, which will
150                 // flush the buffer. (This makes method trace profiling useful to debug crashes.)
151                 if (ActivityThread.currentActivityThread() != null) {
152                     ActivityThread.currentActivityThread().stopProfiling();
153                 }
154 
155                 // Bring up crash dialog, wait for it to be dismissed
156                 ActivityManager.getService().handleApplicationCrash(
157                         mApplicationObject, new ApplicationErrorReport.ParcelableCrashInfo(e));
158             } catch (Throwable t2) {
159                 if (t2 instanceof DeadObjectException) {
160                     // System process is dead; ignore
161                 } else {
162                     try {
163                         Clog_e(TAG, "Error reporting crash", t2);
164                     } catch (Throwable t3) {
165                         // Even Clog_e() fails!  Oh well.
166                     }
167                 }
168             } finally {
169                 // Try everything to make sure this process goes away.
170                 Process.killProcess(Process.myPid());
171                 System.exit(10);
172             }
173         }
174 
175         /**
176          * Ensures that the logging handler has been triggered.
177          *
178          * See b/73380984. This reinstates the pre-O behavior of
179          *
180          *   {@code thread.getUncaughtExceptionHandler().uncaughtException(thread, e);}
181          *
182          * logging the exception (in addition to killing the app). This behavior
183          * was never documented / guaranteed but helps in diagnostics of apps
184          * using the pattern.
185          *
186          * If this KillApplicationHandler is invoked the "regular" way (by
187          * {@link Thread#dispatchUncaughtException(Throwable)
188          * Thread.dispatchUncaughtException} in case of an uncaught exception)
189          * then the pre-handler (expected to be {@link #mLoggingHandler}) will already
190          * have run. Otherwise, we manually invoke it here.
191          */
ensureLogging(Thread t, Throwable e)192         private void ensureLogging(Thread t, Throwable e) {
193             if (!mLoggingHandler.mTriggered) {
194                 try {
195                     mLoggingHandler.uncaughtException(t, e);
196                 } catch (Throwable loggingThrowable) {
197                     // Ignored.
198                 }
199             }
200         }
201     }
202 
203     /**
204      * Common initialization that (unlike {@link #commonInit()} should happen prior to
205      * the Zygote fork.
206      */
preForkInit()207     public static void preForkInit() {
208         if (DEBUG) Slog.d(TAG, "Entered preForkInit.");
209         RuntimeInit.enableDdms();
210         // TODO(b/142019040#comment13): Decide whether to load the default instance eagerly, i.e.
211         // MimeMap.setDefault(DefaultMimeMapFactory.create());
212         /*
213          * Replace libcore's minimal default mapping between MIME types and file
214          * extensions with a mapping that's suitable for Android. Android's mapping
215          * contains many more entries that are derived from IANA registrations but
216          * with several customizations (extensions, overrides).
217          */
218         MimeMap.setDefaultSupplier(DefaultMimeMapFactory::create);
219     }
220 
221     @UnsupportedAppUsage
commonInit()222     protected static final void commonInit() {
223         if (DEBUG) Slog.d(TAG, "Entered RuntimeInit!");
224 
225         /*
226          * set handlers; these apply to all threads in the VM. Apps can replace
227          * the default handler, but not the pre handler.
228          */
229         LoggingHandler loggingHandler = new LoggingHandler();
230         RuntimeHooks.setUncaughtExceptionPreHandler(loggingHandler);
231         Thread.setDefaultUncaughtExceptionHandler(new KillApplicationHandler(loggingHandler));
232 
233         /*
234          * Install a time zone supplier that uses the Android persistent time zone system property.
235          */
236         RuntimeHooks.setTimeZoneIdSupplier(() -> SystemProperties.get("persist.sys.timezone"));
237 
238         /*
239          * Sets handler for java.util.logging to use Android log facilities.
240          * The odd "new instance-and-then-throw-away" is a mirror of how
241          * the "java.util.logging.config.class" system property works. We
242          * can't use the system property here since the logger has almost
243          * certainly already been initialized.
244          */
245         LogManager.getLogManager().reset();
246         new AndroidConfig();
247 
248         /*
249          * Sets the default HTTP User-Agent used by HttpURLConnection.
250          */
251         String userAgent = getDefaultUserAgent();
252         System.setProperty("http.agent", userAgent);
253 
254         /*
255          * Wire socket tagging to traffic stats.
256          */
257         NetworkManagementSocketTagger.install();
258 
259         initialized = true;
260     }
261 
262     /**
263      * Returns an HTTP user agent of the form
264      * "Dalvik/1.1.0 (Linux; U; Android Eclair Build/MAIN)".
265      */
getDefaultUserAgent()266     private static String getDefaultUserAgent() {
267         StringBuilder result = new StringBuilder(64);
268         result.append("Dalvik/");
269         result.append(System.getProperty("java.vm.version")); // such as 1.1.0
270         result.append(" (Linux; U; Android ");
271 
272         String version = Build.VERSION.RELEASE_OR_CODENAME; // "1.0" or "3.4b5"
273         result.append(version.length() > 0 ? version : "1.0");
274 
275         // add the model for the release build
276         if ("REL".equals(Build.VERSION.CODENAME)) {
277             String model = Build.MODEL;
278             if (model.length() > 0) {
279                 result.append("; ");
280                 result.append(model);
281             }
282         }
283         String id = Build.ID; // "MAIN" or "M4-rc20"
284         if (id.length() > 0) {
285             result.append(" Build/");
286             result.append(id);
287         }
288         result.append(")");
289         return result.toString();
290     }
291 
292     /**
293      * Invokes a static "main(argv[]) method on class "className".
294      * Converts various failing exceptions into RuntimeExceptions, with
295      * the assumption that they will then cause the VM instance to exit.
296      *
297      * @param className Fully-qualified class name
298      * @param argv Argument vector for main()
299      * @param classLoader the classLoader to load {@className} with
300      */
findStaticMain(String className, String[] argv, ClassLoader classLoader)301     protected static Runnable findStaticMain(String className, String[] argv,
302             ClassLoader classLoader) {
303         Class<?> cl;
304 
305         try {
306             cl = Class.forName(className, true, classLoader);
307         } catch (ClassNotFoundException ex) {
308             throw new RuntimeException(
309                     "Missing class when invoking static main " + className,
310                     ex);
311         }
312 
313         Method m;
314         try {
315             m = cl.getMethod("main", new Class[] { String[].class });
316         } catch (NoSuchMethodException ex) {
317             throw new RuntimeException(
318                     "Missing static main on " + className, ex);
319         } catch (SecurityException ex) {
320             throw new RuntimeException(
321                     "Problem getting static main on " + className, ex);
322         }
323 
324         int modifiers = m.getModifiers();
325         if (! (Modifier.isStatic(modifiers) && Modifier.isPublic(modifiers))) {
326             throw new RuntimeException(
327                     "Main method is not public and static on " + className);
328         }
329 
330         /*
331          * This throw gets caught in ZygoteInit.main(), which responds
332          * by invoking the exception's run() method. This arrangement
333          * clears up all the stack frames that were required in setting
334          * up the process.
335          */
336         return new MethodAndArgsCaller(m, argv);
337     }
338 
339     @UnsupportedAppUsage
main(String[] argv)340     public static final void main(String[] argv) {
341         preForkInit();
342         if (argv.length == 2 && argv[1].equals("application")) {
343             if (DEBUG) Slog.d(TAG, "RuntimeInit: Starting application");
344             redirectLogStreams();
345         } else {
346             if (DEBUG) Slog.d(TAG, "RuntimeInit: Starting tool");
347         }
348 
349         commonInit();
350 
351         /*
352          * Now that we're running in interpreted code, call back into native code
353          * to run the system.
354          */
355         nativeFinishInit();
356 
357         if (DEBUG) Slog.d(TAG, "Leaving RuntimeInit!");
358     }
359 
applicationInit(int targetSdkVersion, long[] disabledCompatChanges, String[] argv, ClassLoader classLoader)360     protected static Runnable applicationInit(int targetSdkVersion, long[] disabledCompatChanges,
361             String[] argv, ClassLoader classLoader) {
362         // If the application calls System.exit(), terminate the process
363         // immediately without running any shutdown hooks.  It is not possible to
364         // shutdown an Android application gracefully.  Among other things, the
365         // Android runtime shutdown hooks close the Binder driver, which can cause
366         // leftover running threads to crash before the process actually exits.
367         nativeSetExitWithoutCleanup(true);
368 
369         VMRuntime.getRuntime().setTargetSdkVersion(targetSdkVersion);
370         VMRuntime.getRuntime().setDisabledCompatChanges(disabledCompatChanges);
371 
372         final Arguments args = new Arguments(argv);
373 
374         // The end of of the RuntimeInit event (see #zygoteInit).
375         Trace.traceEnd(Trace.TRACE_TAG_ACTIVITY_MANAGER);
376 
377         // Remaining arguments are passed to the start class's static main
378         return findStaticMain(args.startClass, args.startArgs, classLoader);
379     }
380 
381     /**
382      * Redirect System.out and System.err to the Android log.
383      */
redirectLogStreams()384     public static void redirectLogStreams() {
385         System.out.close();
386         System.setOut(new AndroidPrintStream(Log.INFO, "System.out"));
387         System.err.close();
388         System.setErr(new AndroidPrintStream(Log.WARN, "System.err"));
389     }
390 
391     /**
392      * Report a serious error in the current process.  May or may not cause
393      * the process to terminate (depends on system settings).
394      *
395      * @param tag to record with the error
396      * @param t exception describing the error site and conditions
397      */
wtf(String tag, Throwable t, boolean system)398     public static void wtf(String tag, Throwable t, boolean system) {
399         try {
400             boolean exit = false;
401             final IActivityManager am = ActivityManager.getService();
402             if (am != null) {
403                 exit = am.handleApplicationWtf(
404                         mApplicationObject, tag, system,
405                         new ApplicationErrorReport.ParcelableCrashInfo(t),
406                         Process.myPid());
407             } else {
408                 // Unlikely but possible in early system boot
409                 final ApplicationWtfHandler handler = sDefaultApplicationWtfHandler;
410                 if (handler != null) {
411                     exit = handler.handleApplicationWtf(
412                             mApplicationObject, tag, system,
413                             new ApplicationErrorReport.ParcelableCrashInfo(t),
414                             Process.myPid());
415                 } else {
416                     // Simply log the error
417                     Slog.e(TAG, "Original WTF:", t);
418                 }
419             }
420             if (exit) {
421                 // The Activity Manager has already written us off -- now exit.
422                 Process.killProcess(Process.myPid());
423                 System.exit(10);
424             }
425         } catch (Throwable t2) {
426             if (t2 instanceof DeadObjectException) {
427                 // System process is dead; ignore
428             } else {
429                 Slog.e(TAG, "Error reporting WTF", t2);
430                 Slog.e(TAG, "Original WTF:", t);
431             }
432         }
433     }
434 
435     /**
436      * Set the default {@link ApplicationWtfHandler}, in case the ActivityManager is not ready yet.
437      */
setDefaultApplicationWtfHandler(final ApplicationWtfHandler handler)438     public static void setDefaultApplicationWtfHandler(final ApplicationWtfHandler handler) {
439         sDefaultApplicationWtfHandler = handler;
440     }
441 
442     /**
443      * The handler to deal with the serious application errors.
444      */
445     public interface ApplicationWtfHandler {
446         /**
447          * @param app object of the crashing app, null for the system server
448          * @param tag reported by the caller
449          * @param system whether this wtf is coming from the system
450          * @param crashInfo describing the context of the error
451          * @param immediateCallerPid the caller Pid
452          * @return true if the process should exit immediately (WTF is fatal)
453          */
handleApplicationWtf(IBinder app, String tag, boolean system, ApplicationErrorReport.ParcelableCrashInfo crashInfo, int immediateCallerPid)454         boolean handleApplicationWtf(IBinder app, String tag, boolean system,
455                 ApplicationErrorReport.ParcelableCrashInfo crashInfo, int immediateCallerPid);
456     }
457 
458     /**
459      * Set the object identifying this application/process, for reporting VM
460      * errors.
461      */
setApplicationObject(IBinder app)462     public static final void setApplicationObject(IBinder app) {
463         mApplicationObject = app;
464     }
465 
466     @UnsupportedAppUsage
getApplicationObject()467     public static final IBinder getApplicationObject() {
468         return mApplicationObject;
469     }
470 
471     /**
472      * Enable DDMS.
473      */
enableDdms()474     private static void enableDdms() {
475         // Register handlers for DDM messages.
476         android.ddm.DdmRegister.registerHandlers();
477     }
478 
479     /**
480      * Handles argument parsing for args related to the runtime.
481      *
482      * Current recognized args:
483      * <ul>
484      *   <li> <code> [--] &lt;start class name&gt;  &lt;args&gt;
485      * </ul>
486      */
487     static class Arguments {
488         /** first non-option argument */
489         String startClass;
490 
491         /** all following arguments */
492         String[] startArgs;
493 
494         /**
495          * Constructs instance and parses args
496          * @param args runtime command-line args
497          * @throws IllegalArgumentException
498          */
Arguments(String args[])499         Arguments(String args[]) throws IllegalArgumentException {
500             parseArgs(args);
501         }
502 
503         /**
504          * Parses the commandline arguments intended for the Runtime.
505          */
parseArgs(String args[])506         private void parseArgs(String args[])
507                 throws IllegalArgumentException {
508             int curArg = 0;
509             for (; curArg < args.length; curArg++) {
510                 String arg = args[curArg];
511 
512                 if (arg.equals("--")) {
513                     curArg++;
514                     break;
515                 } else if (!arg.startsWith("--")) {
516                     break;
517                 }
518             }
519 
520             if (curArg == args.length) {
521                 throw new IllegalArgumentException("Missing classname argument to RuntimeInit!");
522             }
523 
524             startClass = args[curArg++];
525             startArgs = new String[args.length - curArg];
526             System.arraycopy(args, curArg, startArgs, 0, startArgs.length);
527         }
528     }
529 
530     /**
531      * Helper class which holds a method and arguments and can call them. This is used as part of
532      * a trampoline to get rid of the initial process setup stack frames.
533      */
534     static class MethodAndArgsCaller implements Runnable {
535         /** method to call */
536         private final Method mMethod;
537 
538         /** argument array */
539         private final String[] mArgs;
540 
MethodAndArgsCaller(Method method, String[] args)541         public MethodAndArgsCaller(Method method, String[] args) {
542             mMethod = method;
543             mArgs = args;
544         }
545 
run()546         public void run() {
547             try {
548                 mMethod.invoke(null, new Object[] { mArgs });
549             } catch (IllegalAccessException ex) {
550                 throw new RuntimeException(ex);
551             } catch (InvocationTargetException ex) {
552                 Throwable cause = ex.getCause();
553                 if (cause instanceof RuntimeException) {
554                     throw (RuntimeException) cause;
555                 } else if (cause instanceof Error) {
556                     throw (Error) cause;
557                 }
558                 throw new RuntimeException(ex);
559             }
560         }
561     }
562 }
563