StrictMode.java revision 15ba4061116e088d62a7e05a0037f294f31dff06
1/*
2 * Copyright (C) 2010 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 */
16package android.os;
17
18import android.app.ActivityManagerNative;
19import android.app.ApplicationErrorReport;
20import android.util.Log;
21import android.util.Printer;
22
23import com.android.internal.os.RuntimeInit;
24
25import dalvik.system.BlockGuard;
26
27import java.io.PrintWriter;
28import java.io.StringWriter;
29import java.util.ArrayList;
30import java.util.HashMap;
31
32/**
33 * <p>StrictMode is a developer tool which lets you impose stricter
34 * rules under which your application runs.
35 *
36 * <p>StrictMode is most commonly used to catch accidental disk or
37 * network access on the application's main thread, where UI
38 * operations are received and animations take place.  Keeping disk
39 * and network operations off the main thread makes for much smoother,
40 * more responsive applications.
41 *
42 * <p class="note">Note that even though an Android device's disk is
43 * often on flash memory, many devices run a filesystem on top of that
44 * memory with very limited concurrency.  It's often the case that
45 * almost all disk accesses are fast, but may in individual cases be
46 * dramatically slower when certain I/O is happening in the background
47 * from other processes.  If possible, it's best to assume that such
48 * things are not fast.</p>
49 *
50 * <p>Example code to enable from early in your
51 * {@link android.app.Application}, {@link android.app.Activity}, or
52 * other application component's
53 * {@link android.app.Application#onCreate} method:
54 *
55 * <pre>
56 * public void onCreate() {
57 *     if (DEVELOPER_MODE) {
58 *         StrictMode.setThreadPolicy(StrictMode.DISALLOW_DISK_WRITE |
59 *                 StrictMode.DISALLOW_DISK_READ |
60 *                 StrictMode.DISALLOW_NETWORK |
61 *                 StrictMode.PENALTY_LOG);
62 *     }
63 *     super.onCreate();
64 * }
65 * </pre>
66 *
67 * <p>Then you can watch the output of <code>adb logcat</code> while you
68 * use your application.
69 *
70 * <p>If you find violations that you feel are problematic, there are
71 * a variety of tools to help solve them: threads, {@link android.os.Handler},
72 * {@link android.os.AsyncTask}, {@link android.app.IntentService}, etc.
73 * But don't feel compelled to fix everything that StrictMode finds.  In particular,
74 * a lot of disk accesses are often necessary during the normal activity lifecycle.  Use
75 * StrictMode to find things you did on accident.  Network requests on the UI thread
76 * are almost always a problem, though.
77 *
78 * <p class="note">StrictMode is not a security mechanism and is not
79 * guaranteed to find all disk or network accesses.  While it does
80 * propagate its state across process boundaries when doing
81 * {@link android.os.Binder} calls, it's still ultimately a best
82 * effort mechanism.  Notably, disk or network access from JNI calls
83 * won't necessarily trigger it.  Future versions of Android may catch
84 * more (or fewer) operations, so you should never leave StrictMode
85 * enabled in shipping applications on the Android Market.
86 */
87public final class StrictMode {
88    private static final String TAG = "StrictMode";
89    private static final boolean LOG_V = false;
90
91    // Only log a duplicate stack trace to the logs every second.
92    private static final long MIN_LOG_INTERVAL_MS = 1000;
93
94    // Only show an annoying dialog at most every 30 seconds
95    private static final long MIN_DIALOG_INTERVAL_MS = 30000;
96
97    private StrictMode() {}
98
99    /**
100     * Flag for {@link #setThreadPolicy} to signal that you don't intend for this
101     * thread to write to disk.
102     */
103    public static final int DISALLOW_DISK_WRITE = 0x01;
104
105    /**
106     * Flag for {@link #setThreadPolicy} to signal that you don't intend for this
107     * thread to read from disk.
108     */
109    public static final int DISALLOW_DISK_READ = 0x02;
110
111    /**
112     * Flag for {@link #setThreadPolicy} to signal that you don't intend for this
113     * thread to access the network.
114     */
115    public static final int DISALLOW_NETWORK = 0x04;
116
117    /** @hide */
118    public static final int DISALLOW_MASK =
119            DISALLOW_DISK_WRITE | DISALLOW_DISK_READ | DISALLOW_NETWORK;
120
121    /**
122     * Penalty flag for {@link #setThreadPolicy} to log violations to
123     * the system log, visible with <code>adb logcat</code>.
124     */
125    public static final int PENALTY_LOG = 0x10;  // normal android.util.Log
126
127    /**
128     * Penalty flag for {@link #setThreadPolicy} to show an annoying
129     * dialog to the developer, rate-limited to be only a little
130     * annoying.
131     */
132    public static final int PENALTY_DIALOG = 0x20;
133
134    /**
135     * Penalty flag for {@link #setThreadPolicy} to crash hard if
136     * policy is violated.
137     */
138    public static final int PENALTY_DEATH = 0x40;
139
140    /**
141     * Penalty flag for {@link #setThreadPolicy} to log a stacktrace
142     * and timing data to the
143     * {@link android.os.DropBoxManager DropBox} on policy violation.
144     * Intended mostly for platform integrators doing beta user field
145     * data collection.
146     */
147    public static final int PENALTY_DROPBOX = 0x80;
148
149    /**
150     * Non-public penalty mode which overrides all the other penalty
151     * bits and signals that we're in a Binder call and we should
152     * ignore the other penalty bits and instead serialize back all
153     * our offending stack traces to the caller to ultimately handle
154     * in the originating process.
155     *
156     * This must be kept in sync with the constant in libs/binder/Parcel.cpp
157     *
158     * @hide
159     */
160    public static final int PENALTY_GATHER = 0x100;
161
162    /** @hide */
163    public static final int PENALTY_MASK =
164            PENALTY_LOG | PENALTY_DIALOG |
165            PENALTY_DROPBOX | PENALTY_DEATH;
166
167    /**
168     * Log of strict mode violation stack traces that have occurred
169     * during a Binder call, to be serialized back later to the caller
170     * via Parcel.writeNoException() (amusingly) where the caller can
171     * choose how to react.
172     */
173    private static final ThreadLocal<ArrayList<ViolationInfo>> gatheredViolations =
174            new ThreadLocal<ArrayList<ViolationInfo>>() {
175        @Override protected ArrayList<ViolationInfo> initialValue() {
176            // Starts null to avoid unnecessary allocations when
177            // checking whether there are any violations or not in
178            // hasGatheredViolations() below.
179            return null;
180        }
181    };
182
183    /**
184     * Sets the policy for what actions the current thread isn't
185     * expected to do, as well as the penalty if it does.
186     *
187     * <p>Internally this sets a thread-local integer which is
188     * propagated across cross-process IPC calls, meaning you can
189     * catch violations when a system service or another process
190     * accesses the disk or network on your behalf.
191     *
192     * @param policyMask a bitmask of DISALLOW_* and PENALTY_* values,
193     *     e.g. {@link #DISALLOW_DISK_READ}, {@link #DISALLOW_DISK_WRITE},
194     *     {@link #DISALLOW_NETWORK}, {@link #PENALTY_LOG}.
195     */
196    public static void setThreadPolicy(final int policyMask) {
197        // In addition to the Java-level thread-local in Dalvik's
198        // BlockGuard, we also need to keep a native thread-local in
199        // Binder in order to propagate the value across Binder calls,
200        // even across native-only processes.  The two are kept in
201        // sync via the callback to onStrictModePolicyChange, below.
202        setBlockGuardPolicy(policyMask);
203
204        // And set the Android native version...
205        Binder.setThreadStrictModePolicy(policyMask);
206    }
207
208    // Sets the policy in Dalvik/libcore (BlockGuard)
209    private static void setBlockGuardPolicy(final int policyMask) {
210        if (policyMask == 0) {
211            BlockGuard.setThreadPolicy(BlockGuard.LAX_POLICY);
212            return;
213        }
214        BlockGuard.Policy policy = BlockGuard.getThreadPolicy();
215        if (!(policy instanceof AndroidBlockGuardPolicy)) {
216            BlockGuard.setThreadPolicy(new AndroidBlockGuardPolicy(policyMask));
217        } else {
218            AndroidBlockGuardPolicy androidPolicy = (AndroidBlockGuardPolicy) policy;
219            androidPolicy.setPolicyMask(policyMask);
220        }
221    }
222
223    private static class StrictModeNetworkViolation extends BlockGuard.BlockGuardPolicyException {
224        public StrictModeNetworkViolation(int policyMask) {
225            super(policyMask, DISALLOW_NETWORK);
226        }
227    }
228
229    private static class StrictModeDiskReadViolation extends BlockGuard.BlockGuardPolicyException {
230        public StrictModeDiskReadViolation(int policyMask) {
231            super(policyMask, DISALLOW_DISK_READ);
232        }
233    }
234
235    private static class StrictModeDiskWriteViolation extends BlockGuard.BlockGuardPolicyException {
236        public StrictModeDiskWriteViolation(int policyMask) {
237            super(policyMask, DISALLOW_DISK_WRITE);
238        }
239    }
240
241    /**
242     * Returns the bitmask of the current thread's policy.
243     *
244     * @return the bitmask of all the DISALLOW_* and PENALTY_* bits currently enabled
245     */
246    public static int getThreadPolicy() {
247        return BlockGuard.getThreadPolicy().getPolicyMask();
248    }
249
250    /**
251     * A convenience wrapper around {@link #getThreadPolicy} and
252     * {@link #setThreadPolicy}.  Updates the current thread's policy
253     * mask to allow both reading &amp; writing to disk, returning the
254     * old policy so you can restore it at the end of a block.
255     *
256     * @return the old policy mask, to be passed to setThreadPolicy to
257     *         restore the policy.
258     */
259    public static int allowThreadDiskWrites() {
260        int oldPolicy = getThreadPolicy();
261        int newPolicy = oldPolicy & ~(DISALLOW_DISK_WRITE | DISALLOW_DISK_READ);
262        if (newPolicy != oldPolicy) {
263            setThreadPolicy(newPolicy);
264        }
265        return oldPolicy;
266    }
267
268    /**
269     * A convenience wrapper around {@link #getThreadPolicy} and
270     * {@link #setThreadPolicy}.  Updates the current thread's policy
271     * mask to allow reading from disk, returning the old
272     * policy so you can restore it at the end of a block.
273     *
274     * @return the old policy mask, to be passed to setThreadPolicy to
275     *         restore the policy.
276     */
277    public static int allowThreadDiskReads() {
278        int oldPolicy = getThreadPolicy();
279        int newPolicy = oldPolicy & ~(DISALLOW_DISK_READ);
280        if (newPolicy != oldPolicy) {
281            setThreadPolicy(newPolicy);
282        }
283        return oldPolicy;
284    }
285
286    /**
287     * Enable DropBox logging for debug phone builds.
288     *
289     * @hide
290     */
291    public static boolean conditionallyEnableDebugLogging() {
292        // For debug builds, log event loop stalls to dropbox for analysis.
293        // Similar logic also appears in ActivityThread.java for system apps.
294        if ("user".equals(Build.TYPE)) {
295            return false;
296        }
297        StrictMode.setThreadPolicy(
298            StrictMode.DISALLOW_DISK_WRITE |
299            StrictMode.DISALLOW_DISK_READ |
300            StrictMode.DISALLOW_NETWORK |
301            StrictMode.PENALTY_DROPBOX);
302        return true;
303    }
304
305    /**
306     * Parses the BlockGuard policy mask out from the Exception's
307     * getMessage() String value.  Kinda gross, but least
308     * invasive.  :/
309     *
310     * Input is of form "policy=137 violation=64"
311     *
312     * Returns 0 on failure, which is a valid policy, but not a
313     * valid policy during a violation (else there must've been
314     * some policy in effect to violate).
315     */
316    private static int parsePolicyFromMessage(String message) {
317        if (message == null || !message.startsWith("policy=")) {
318            return 0;
319        }
320        int spaceIndex = message.indexOf(' ');
321        if (spaceIndex == -1) {
322            return 0;
323        }
324        String policyString = message.substring(7, spaceIndex);
325        try {
326            return Integer.valueOf(policyString).intValue();
327        } catch (NumberFormatException e) {
328            return 0;
329        }
330    }
331
332    /**
333     * Like parsePolicyFromMessage(), but returns the violation.
334     */
335    private static int parseViolationFromMessage(String message) {
336        if (message == null) {
337            return 0;
338        }
339        int violationIndex = message.indexOf("violation=");
340        if (violationIndex == -1) {
341            return 0;
342        }
343        String violationString = message.substring(violationIndex + 10);
344        try {
345            return Integer.valueOf(violationString).intValue();
346        } catch (NumberFormatException e) {
347            return 0;
348        }
349    }
350
351    private static class AndroidBlockGuardPolicy implements BlockGuard.Policy {
352        private int mPolicyMask;
353
354        // Map from violation stacktrace hashcode -> uptimeMillis of
355        // last violation.  No locking needed, as this is only
356        // accessed by the same thread.
357        private final HashMap<Integer, Long> mLastViolationTime = new HashMap<Integer, Long>();
358
359        public AndroidBlockGuardPolicy(final int policyMask) {
360            mPolicyMask = policyMask;
361        }
362
363        @Override
364        public String toString() {
365            return "AndroidBlockGuardPolicy; mPolicyMask=" + mPolicyMask;
366        }
367
368        // Part of BlockGuard.Policy interface:
369        public int getPolicyMask() {
370            return mPolicyMask;
371        }
372
373        // Part of BlockGuard.Policy interface:
374        public void onWriteToDisk() {
375            if ((mPolicyMask & DISALLOW_DISK_WRITE) == 0) {
376                return;
377            }
378            BlockGuard.BlockGuardPolicyException e = new StrictModeDiskWriteViolation(mPolicyMask);
379            e.fillInStackTrace();
380            startHandlingViolationException(e);
381        }
382
383        // Part of BlockGuard.Policy interface:
384        public void onReadFromDisk() {
385            if ((mPolicyMask & DISALLOW_DISK_READ) == 0) {
386                return;
387            }
388            BlockGuard.BlockGuardPolicyException e = new StrictModeDiskReadViolation(mPolicyMask);
389            e.fillInStackTrace();
390            startHandlingViolationException(e);
391        }
392
393        // Part of BlockGuard.Policy interface:
394        public void onNetwork() {
395            if ((mPolicyMask & DISALLOW_NETWORK) == 0) {
396                return;
397            }
398            BlockGuard.BlockGuardPolicyException e = new StrictModeNetworkViolation(mPolicyMask);
399            e.fillInStackTrace();
400            startHandlingViolationException(e);
401        }
402
403        public void setPolicyMask(int policyMask) {
404            mPolicyMask = policyMask;
405        }
406
407        // Start handling a violation that just started and hasn't
408        // actually run yet (e.g. no disk write or network operation
409        // has yet occurred).  This sees if we're in an event loop
410        // thread and, if so, uses it to roughly measure how long the
411        // violation took.
412        void startHandlingViolationException(BlockGuard.BlockGuardPolicyException e) {
413            final ViolationInfo info = new ViolationInfo(e, e.getPolicy());
414            info.violationUptimeMillis = SystemClock.uptimeMillis();
415            handleViolationWithTimingAttempt(info);
416        }
417
418        private static final ThreadLocal<ArrayList<ViolationInfo>> violationsBeingTimed =
419                new ThreadLocal<ArrayList<ViolationInfo>>() {
420            @Override protected ArrayList<ViolationInfo> initialValue() {
421                return new ArrayList<ViolationInfo>();
422            }
423        };
424
425        // Attempts to fill in the provided ViolationInfo's
426        // durationMillis field if this thread has a Looper we can use
427        // to measure with.  We measure from the time of violation
428        // until the time the looper is idle again (right before
429        // the next epoll_wait)
430        void handleViolationWithTimingAttempt(final ViolationInfo info) {
431            Looper looper = Looper.myLooper();
432
433            // Without a Looper, we're unable to time how long the
434            // violation takes place.  This case should be rare, as
435            // most users will care about timing violations that
436            // happen on their main UI thread.  Note that this case is
437            // also hit when a violation takes place in a Binder
438            // thread, in "gather" mode.  In this case, the duration
439            // of the violation is computed by the ultimate caller and
440            // its Looper, if any.
441            // TODO: if in gather mode, ignore Looper.myLooper() and always
442            //       go into this immediate mode?
443            if (looper == null) {
444                info.durationMillis = -1;  // unknown (redundant, already set)
445                handleViolation(info);
446                return;
447            }
448
449            MessageQueue queue = Looper.myQueue();
450            final ArrayList<ViolationInfo> records = violationsBeingTimed.get();
451            if (records.size() >= 10) {
452                // Not worth measuring.  Too many offenses in one loop.
453                return;
454            }
455            records.add(info);
456            if (records.size() > 1) {
457                // There's already been a violation this loop, so we've already
458                // registered an idle handler to process the list of violations
459                // at the end of this Looper's loop.
460                return;
461            }
462
463            queue.addIdleHandler(new MessageQueue.IdleHandler() {
464                    public boolean queueIdle() {
465                        long loopFinishTime = SystemClock.uptimeMillis();
466                        for (int n = 0; n < records.size(); ++n) {
467                            ViolationInfo v = records.get(n);
468                            v.violationNumThisLoop = n + 1;
469                            v.durationMillis =
470                                    (int) (loopFinishTime - v.violationUptimeMillis);
471                            handleViolation(v);
472                        }
473                        records.clear();
474                        return false;  // remove this idle handler from the array
475                    }
476                });
477        }
478
479        // Note: It's possible (even quite likely) that the
480        // thread-local policy mask has changed from the time the
481        // violation fired and now (after the violating code ran) due
482        // to people who push/pop temporary policy in regions of code,
483        // hence the policy being passed around.
484        void handleViolation(final ViolationInfo info) {
485            if (info == null || info.crashInfo == null || info.crashInfo.stackTrace == null) {
486                Log.wtf(TAG, "unexpected null stacktrace");
487                return;
488            }
489
490            if (LOG_V) Log.d(TAG, "handleViolation; policy=" + info.policy);
491
492            if ((info.policy & PENALTY_GATHER) != 0) {
493                ArrayList<ViolationInfo> violations = gatheredViolations.get();
494                if (violations == null) {
495                    violations = new ArrayList<ViolationInfo>(1);
496                    gatheredViolations.set(violations);
497                } else if (violations.size() >= 5) {
498                    // Too many.  In a loop or something?  Don't gather them all.
499                    return;
500                }
501                for (ViolationInfo previous : violations) {
502                    if (info.crashInfo.stackTrace.equals(previous.crashInfo.stackTrace)) {
503                        // Duplicate. Don't log.
504                        return;
505                    }
506                }
507                violations.add(info);
508                return;
509            }
510
511            // Not perfect, but fast and good enough for dup suppression.
512            Integer crashFingerprint = info.crashInfo.stackTrace.hashCode();
513            long lastViolationTime = 0;
514            if (mLastViolationTime.containsKey(crashFingerprint)) {
515                lastViolationTime = mLastViolationTime.get(crashFingerprint);
516            }
517            long now = SystemClock.uptimeMillis();
518            mLastViolationTime.put(crashFingerprint, now);
519            long timeSinceLastViolationMillis = lastViolationTime == 0 ?
520                    Long.MAX_VALUE : (now - lastViolationTime);
521
522            if ((info.policy & PENALTY_LOG) != 0 &&
523                timeSinceLastViolationMillis > MIN_LOG_INTERVAL_MS) {
524                if (info.durationMillis != -1) {
525                    Log.d(TAG, "StrictMode policy violation; ~duration=" +
526                          info.durationMillis + " ms: " + info.crashInfo.stackTrace);
527                } else {
528                    Log.d(TAG, "StrictMode policy violation: " + info.crashInfo.stackTrace);
529                }
530            }
531
532            // The violationMask, passed to ActivityManager, is a
533            // subset of the original StrictMode policy bitmask, with
534            // only the bit violated and penalty bits to be executed
535            // by the ActivityManagerService remaining set.
536            int violationMaskSubset = 0;
537
538            if ((info.policy & PENALTY_DIALOG) != 0 &&
539                timeSinceLastViolationMillis > MIN_DIALOG_INTERVAL_MS) {
540                violationMaskSubset |= PENALTY_DIALOG;
541            }
542
543            if ((info.policy & PENALTY_DROPBOX) != 0 && lastViolationTime == 0) {
544                violationMaskSubset |= PENALTY_DROPBOX;
545            }
546
547            if (violationMaskSubset != 0) {
548                int violationBit = parseViolationFromMessage(info.crashInfo.exceptionMessage);
549                violationMaskSubset |= violationBit;
550                final int savedPolicy = getThreadPolicy();
551                try {
552                    // First, remove any policy before we call into the Activity Manager,
553                    // otherwise we'll infinite recurse as we try to log policy violations
554                    // to disk, thus violating policy, thus requiring logging, etc...
555                    // We restore the current policy below, in the finally block.
556                    setThreadPolicy(0);
557
558                    ActivityManagerNative.getDefault().handleApplicationStrictModeViolation(
559                        RuntimeInit.getApplicationObject(),
560                        violationMaskSubset,
561                        info);
562                } catch (RemoteException e) {
563                    Log.e(TAG, "RemoteException trying to handle StrictMode violation", e);
564                } finally {
565                    // Restore the policy.
566                    setThreadPolicy(savedPolicy);
567                }
568            }
569
570            if ((info.policy & PENALTY_DEATH) != 0) {
571                System.err.println("StrictMode policy violation with POLICY_DEATH; shutting down.");
572                Process.killProcess(Process.myPid());
573                System.exit(10);
574            }
575        }
576    }
577
578    /**
579     * Called from Parcel.writeNoException()
580     */
581    /* package */ static boolean hasGatheredViolations() {
582        return gatheredViolations.get() != null;
583    }
584
585    /**
586     * Called from Parcel.writeException(), so we drop this memory and
587     * don't incorrectly attribute it to the wrong caller on the next
588     * Binder call on this thread.
589     */
590    /* package */ static void clearGatheredViolations() {
591        gatheredViolations.set(null);
592    }
593
594    /**
595     * Called from Parcel.writeNoException()
596     */
597    /* package */ static void writeGatheredViolationsToParcel(Parcel p) {
598        ArrayList<ViolationInfo> violations = gatheredViolations.get();
599        if (violations == null) {
600            p.writeInt(0);
601        } else {
602            p.writeInt(violations.size());
603            for (int i = 0; i < violations.size(); ++i) {
604                violations.get(i).writeToParcel(p, 0 /* unused flags? */);
605            }
606            if (LOG_V) Log.d(TAG, "wrote violations to response parcel; num=" + violations.size());
607            violations.clear(); // somewhat redundant, as we're about to null the threadlocal
608        }
609        gatheredViolations.set(null);
610    }
611
612    private static class LogStackTrace extends Exception {}
613
614    /**
615     * Called from Parcel.readException() when the exception is EX_STRICT_MODE_VIOLATIONS,
616     * we here read back all the encoded violations.
617     */
618    /* package */ static void readAndHandleBinderCallViolations(Parcel p) {
619        // Our own stack trace to append
620        StringWriter sw = new StringWriter();
621        new LogStackTrace().printStackTrace(new PrintWriter(sw));
622        String ourStack = sw.toString();
623
624        int policyMask = getThreadPolicy();
625        boolean currentlyGathering = (policyMask & PENALTY_GATHER) != 0;
626
627        int numViolations = p.readInt();
628        for (int i = 0; i < numViolations; ++i) {
629            if (LOG_V) Log.d(TAG, "strict mode violation stacks read from binder call.  i=" + i);
630            ViolationInfo info = new ViolationInfo(p, !currentlyGathering);
631            info.crashInfo.stackTrace += "# via Binder call with stack:\n" + ourStack;
632            BlockGuard.Policy policy = BlockGuard.getThreadPolicy();
633            if (policy instanceof AndroidBlockGuardPolicy) {
634                ((AndroidBlockGuardPolicy) policy).handleViolationWithTimingAttempt(info);
635            }
636        }
637    }
638
639    /**
640     * Called from android_util_Binder.cpp's
641     * android_os_Parcel_enforceInterface when an incoming Binder call
642     * requires changing the StrictMode policy mask.  The role of this
643     * function is to ask Binder for its current (native) thread-local
644     * policy value and synchronize it to libcore's (Java)
645     * thread-local policy value.
646     */
647    private static void onBinderStrictModePolicyChange(int newPolicy) {
648        setBlockGuardPolicy(newPolicy);
649    }
650
651    /**
652     * Parcelable that gets sent in Binder call headers back to callers
653     * to report violations that happened during a cross-process call.
654     *
655     * @hide
656     */
657    public static class ViolationInfo {
658        /**
659         * Stack and other stuff info.
660         */
661        public final ApplicationErrorReport.CrashInfo crashInfo;
662
663        /**
664         * The strict mode policy mask at the time of violation.
665         */
666        public final int policy;
667
668        /**
669         * The wall time duration of the violation, when known.  -1 when
670         * not known.
671         */
672        public int durationMillis = -1;
673
674        /**
675         * Which violation number this was (1-based) since the last Looper loop,
676         * from the perspective of the root caller (if it crossed any processes
677         * via Binder calls).  The value is 0 if the root caller wasn't on a Looper
678         * thread.
679         */
680        public int violationNumThisLoop;
681
682        /**
683         * The time (in terms of SystemClock.uptimeMillis()) that the
684         * violation occurred.
685         */
686        public long violationUptimeMillis;
687
688        /**
689         * Create an uninitialized instance of ViolationInfo
690         */
691        public ViolationInfo() {
692            crashInfo = null;
693            policy = 0;
694        }
695
696        /**
697         * Create an instance of ViolationInfo initialized from an exception.
698         */
699        public ViolationInfo(Throwable tr, int policy) {
700            crashInfo = new ApplicationErrorReport.CrashInfo(tr);
701            violationUptimeMillis = SystemClock.uptimeMillis();
702            this.policy = policy;
703        }
704
705        /**
706         * Create an instance of ViolationInfo initialized from a Parcel.
707         */
708        public ViolationInfo(Parcel in) {
709            this(in, false);
710        }
711
712        /**
713         * Create an instance of ViolationInfo initialized from a Parcel.
714         *
715         * @param unsetGatheringBit if true, the caller is the root caller
716         *   and the gathering penalty should be removed.
717         */
718        public ViolationInfo(Parcel in, boolean unsetGatheringBit) {
719            crashInfo = new ApplicationErrorReport.CrashInfo(in);
720            int rawPolicy = in.readInt();
721            if (unsetGatheringBit) {
722                policy = rawPolicy & ~PENALTY_GATHER;
723            } else {
724                policy = rawPolicy;
725            }
726            durationMillis = in.readInt();
727            violationNumThisLoop = in.readInt();
728            violationUptimeMillis = in.readLong();
729        }
730
731        /**
732         * Save a ViolationInfo instance to a parcel.
733         */
734        public void writeToParcel(Parcel dest, int flags) {
735            crashInfo.writeToParcel(dest, flags);
736            dest.writeInt(policy);
737            dest.writeInt(durationMillis);
738            dest.writeInt(violationNumThisLoop);
739            dest.writeLong(violationUptimeMillis);
740        }
741
742
743        /**
744         * Dump a ViolationInfo instance to a Printer.
745         */
746        public void dump(Printer pw, String prefix) {
747            crashInfo.dump(pw, prefix);
748            pw.println(prefix + "policy: " + policy);
749            if (durationMillis != -1) {
750                pw.println(prefix + "durationMillis: " + durationMillis);
751            }
752            if (violationNumThisLoop != 0) {
753                pw.println(prefix + "violationNumThisLoop: " + violationNumThisLoop);
754            }
755            pw.println(prefix + "violationUptimeMillis: " + violationUptimeMillis);
756        }
757
758    }
759}
760