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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 android.os;
18 
19 import android.net.LocalSocketAddress;
20 import android.net.LocalSocket;
21 import android.util.Log;
22 import dalvik.system.Zygote;
23 
24 import java.io.BufferedWriter;
25 import java.io.DataInputStream;
26 import java.io.IOException;
27 import java.io.OutputStreamWriter;
28 import java.util.ArrayList;
29 
30 /*package*/ class ZygoteStartFailedEx extends Exception {
31     /**
32      * Something prevented the zygote process startup from happening normally
33      */
34 
ZygoteStartFailedEx()35     ZygoteStartFailedEx() {};
ZygoteStartFailedEx(String s)36     ZygoteStartFailedEx(String s) {super(s);}
ZygoteStartFailedEx(Throwable cause)37     ZygoteStartFailedEx(Throwable cause) {super(cause);}
38 }
39 
40 /**
41  * Tools for managing OS processes.
42  */
43 public class Process {
44     private static final String LOG_TAG = "Process";
45 
46     private static final String ZYGOTE_SOCKET = "zygote";
47 
48     /**
49      * Name of a process for running the platform's media services.
50      * {@hide}
51      */
52     public static final String ANDROID_SHARED_MEDIA = "com.android.process.media";
53 
54     /**
55      * Name of the process that Google content providers can share.
56      * {@hide}
57      */
58     public static final String GOOGLE_SHARED_APP_CONTENT = "com.google.process.content";
59 
60     /**
61      * Defines the UID/GID under which system code runs.
62      */
63     public static final int SYSTEM_UID = 1000;
64 
65     /**
66      * Defines the UID/GID under which the telephony code runs.
67      */
68     public static final int PHONE_UID = 1001;
69 
70     /**
71      * Defines the UID/GID for the user shell.
72      * @hide
73      */
74     public static final int SHELL_UID = 2000;
75 
76     /**
77      * Defines the UID/GID for the log group.
78      * @hide
79      */
80     public static final int LOG_UID = 1007;
81 
82     /**
83      * Defines the UID/GID for the WIFI supplicant process.
84      * @hide
85      */
86     public static final int WIFI_UID = 1010;
87 
88     /**
89      * Defines the UID/GID for the mediaserver process.
90      * @hide
91      */
92     public static final int MEDIA_UID = 1013;
93 
94     /**
95      * Defines the UID/GID for the DRM process.
96      * @hide
97      */
98     public static final int DRM_UID = 1019;
99 
100     /**
101      * Defines the GID for the group that allows write access to the SD card.
102      * @hide
103      */
104     public static final int SDCARD_RW_GID = 1015;
105 
106     /**
107      * Defines the UID/GID for the group that controls VPN services.
108      * @hide
109      */
110     public static final int VPN_UID = 1016;
111 
112     /**
113      * Defines the UID/GID for the NFC service process.
114      * @hide
115      */
116     public static final int NFC_UID = 1027;
117 
118     /**
119      * Defines the GID for the group that allows write access to the internal media storage.
120      * @hide
121      */
122     public static final int MEDIA_RW_GID = 1023;
123 
124     /**
125      * Defines the start of a range of UIDs (and GIDs), going from this
126      * number to {@link #LAST_APPLICATION_UID} that are reserved for assigning
127      * to applications.
128      */
129     public static final int FIRST_APPLICATION_UID = 10000;
130     /**
131      * Last of application-specific UIDs starting at
132      * {@link #FIRST_APPLICATION_UID}.
133      */
134     public static final int LAST_APPLICATION_UID = 19999;
135 
136     /**
137      * First uid used for fully isolated sandboxed processes (with no permissions of their own)
138      * @hide
139      */
140     public static final int FIRST_ISOLATED_UID = 99000;
141 
142     /**
143      * Last uid used for fully isolated sandboxed processes (with no permissions of their own)
144      * @hide
145      */
146     public static final int LAST_ISOLATED_UID = 99999;
147 
148     /**
149      * Defines a secondary group id for access to the bluetooth hardware.
150      */
151     public static final int BLUETOOTH_GID = 2000;
152 
153     /**
154      * Standard priority of application threads.
155      * Use with {@link #setThreadPriority(int)} and
156      * {@link #setThreadPriority(int, int)}, <b>not</b> with the normal
157      * {@link java.lang.Thread} class.
158      */
159     public static final int THREAD_PRIORITY_DEFAULT = 0;
160 
161     /*
162      * ***************************************
163      * ** Keep in sync with utils/threads.h **
164      * ***************************************
165      */
166 
167     /**
168      * Lowest available thread priority.  Only for those who really, really
169      * don't want to run if anything else is happening.
170      * Use with {@link #setThreadPriority(int)} and
171      * {@link #setThreadPriority(int, int)}, <b>not</b> with the normal
172      * {@link java.lang.Thread} class.
173      */
174     public static final int THREAD_PRIORITY_LOWEST = 19;
175 
176     /**
177      * Standard priority background threads.  This gives your thread a slightly
178      * lower than normal priority, so that it will have less chance of impacting
179      * the responsiveness of the user interface.
180      * Use with {@link #setThreadPriority(int)} and
181      * {@link #setThreadPriority(int, int)}, <b>not</b> with the normal
182      * {@link java.lang.Thread} class.
183      */
184     public static final int THREAD_PRIORITY_BACKGROUND = 10;
185 
186     /**
187      * Standard priority of threads that are currently running a user interface
188      * that the user is interacting with.  Applications can not normally
189      * change to this priority; the system will automatically adjust your
190      * application threads as the user moves through the UI.
191      * Use with {@link #setThreadPriority(int)} and
192      * {@link #setThreadPriority(int, int)}, <b>not</b> with the normal
193      * {@link java.lang.Thread} class.
194      */
195     public static final int THREAD_PRIORITY_FOREGROUND = -2;
196 
197     /**
198      * Standard priority of system display threads, involved in updating
199      * the user interface.  Applications can not
200      * normally change to this priority.
201      * Use with {@link #setThreadPriority(int)} and
202      * {@link #setThreadPriority(int, int)}, <b>not</b> with the normal
203      * {@link java.lang.Thread} class.
204      */
205     public static final int THREAD_PRIORITY_DISPLAY = -4;
206 
207     /**
208      * Standard priority of the most important display threads, for compositing
209      * the screen and retrieving input events.  Applications can not normally
210      * change to this priority.
211      * Use with {@link #setThreadPriority(int)} and
212      * {@link #setThreadPriority(int, int)}, <b>not</b> with the normal
213      * {@link java.lang.Thread} class.
214      */
215     public static final int THREAD_PRIORITY_URGENT_DISPLAY = -8;
216 
217     /**
218      * Standard priority of audio threads.  Applications can not normally
219      * change to this priority.
220      * Use with {@link #setThreadPriority(int)} and
221      * {@link #setThreadPriority(int, int)}, <b>not</b> with the normal
222      * {@link java.lang.Thread} class.
223      */
224     public static final int THREAD_PRIORITY_AUDIO = -16;
225 
226     /**
227      * Standard priority of the most important audio threads.
228      * Applications can not normally change to this priority.
229      * Use with {@link #setThreadPriority(int)} and
230      * {@link #setThreadPriority(int, int)}, <b>not</b> with the normal
231      * {@link java.lang.Thread} class.
232      */
233     public static final int THREAD_PRIORITY_URGENT_AUDIO = -19;
234 
235     /**
236      * Minimum increment to make a priority more favorable.
237      */
238     public static final int THREAD_PRIORITY_MORE_FAVORABLE = -1;
239 
240     /**
241      * Minimum increment to make a priority less favorable.
242      */
243     public static final int THREAD_PRIORITY_LESS_FAVORABLE = +1;
244 
245     /**
246      * Default scheduling policy
247      * @hide
248      */
249     public static final int SCHED_OTHER = 0;
250 
251     /**
252      * First-In First-Out scheduling policy
253      * @hide
254      */
255     public static final int SCHED_FIFO = 1;
256 
257     /**
258      * Round-Robin scheduling policy
259      * @hide
260      */
261     public static final int SCHED_RR = 2;
262 
263     /**
264      * Batch scheduling policy
265      * @hide
266      */
267     public static final int SCHED_BATCH = 3;
268 
269     /**
270      * Idle scheduling policy
271      * @hide
272      */
273     public static final int SCHED_IDLE = 5;
274 
275     // Keep in sync with SP_* constants of enum type SchedPolicy
276     // declared in system/core/include/cutils/sched_policy.h,
277     // except THREAD_GROUP_DEFAULT does not correspond to any SP_* value.
278 
279     /**
280      * Default thread group -
281      * has meaning with setProcessGroup() only, cannot be used with setThreadGroup().
282      * When used with setProcessGroup(), the group of each thread in the process
283      * is conditionally changed based on that thread's current priority, as follows:
284      * threads with priority numerically less than THREAD_PRIORITY_BACKGROUND
285      * are moved to foreground thread group.  All other threads are left unchanged.
286      * @hide
287      */
288     public static final int THREAD_GROUP_DEFAULT = -1;
289 
290     /**
291      * Background thread group - All threads in
292      * this group are scheduled with a reduced share of the CPU.
293      * Value is same as constant SP_BACKGROUND of enum SchedPolicy.
294      * FIXME rename to THREAD_GROUP_BACKGROUND.
295      * @hide
296      */
297     public static final int THREAD_GROUP_BG_NONINTERACTIVE = 0;
298 
299     /**
300      * Foreground thread group - All threads in
301      * this group are scheduled with a normal share of the CPU.
302      * Value is same as constant SP_FOREGROUND of enum SchedPolicy.
303      * Not used at this level.
304      * @hide
305      **/
306     private static final int THREAD_GROUP_FOREGROUND = 1;
307 
308     /**
309      * System thread group.
310      * @hide
311      **/
312     public static final int THREAD_GROUP_SYSTEM = 2;
313 
314     /**
315      * Application audio thread group.
316      * @hide
317      **/
318     public static final int THREAD_GROUP_AUDIO_APP = 3;
319 
320     /**
321      * System audio thread group.
322      * @hide
323      **/
324     public static final int THREAD_GROUP_AUDIO_SYS = 4;
325 
326     public static final int SIGNAL_QUIT = 3;
327     public static final int SIGNAL_KILL = 9;
328     public static final int SIGNAL_USR1 = 10;
329 
330     // State for communicating with zygote process
331 
332     static LocalSocket sZygoteSocket;
333     static DataInputStream sZygoteInputStream;
334     static BufferedWriter sZygoteWriter;
335 
336     /** true if previous zygote open failed */
337     static boolean sPreviousZygoteOpenFailed;
338 
339     /**
340      * Start a new process.
341      *
342      * <p>If processes are enabled, a new process is created and the
343      * static main() function of a <var>processClass</var> is executed there.
344      * The process will continue running after this function returns.
345      *
346      * <p>If processes are not enabled, a new thread in the caller's
347      * process is created and main() of <var>processClass</var> called there.
348      *
349      * <p>The niceName parameter, if not an empty string, is a custom name to
350      * give to the process instead of using processClass.  This allows you to
351      * make easily identifyable processes even if you are using the same base
352      * <var>processClass</var> to start them.
353      *
354      * @param processClass The class to use as the process's main entry
355      *                     point.
356      * @param niceName A more readable name to use for the process.
357      * @param uid The user-id under which the process will run.
358      * @param gid The group-id under which the process will run.
359      * @param gids Additional group-ids associated with the process.
360      * @param debugFlags Additional flags.
361      * @param targetSdkVersion The target SDK version for the app.
362      * @param zygoteArgs Additional arguments to supply to the zygote process.
363      *
364      * @return An object that describes the result of the attempt to start the process.
365      * @throws RuntimeException on fatal start failure
366      *
367      * {@hide}
368      */
start(final String processClass, final String niceName, int uid, int gid, int[] gids, int debugFlags, int targetSdkVersion, String[] zygoteArgs)369     public static final ProcessStartResult start(final String processClass,
370                                   final String niceName,
371                                   int uid, int gid, int[] gids,
372                                   int debugFlags, int targetSdkVersion,
373                                   String[] zygoteArgs) {
374         try {
375             return startViaZygote(processClass, niceName, uid, gid, gids,
376                     debugFlags, targetSdkVersion, zygoteArgs);
377         } catch (ZygoteStartFailedEx ex) {
378             Log.e(LOG_TAG,
379                     "Starting VM process through Zygote failed");
380             throw new RuntimeException(
381                     "Starting VM process through Zygote failed", ex);
382         }
383     }
384 
385     /** retry interval for opening a zygote socket */
386     static final int ZYGOTE_RETRY_MILLIS = 500;
387 
388     /**
389      * Tries to open socket to Zygote process if not already open. If
390      * already open, does nothing.  May block and retry.
391      */
openZygoteSocketIfNeeded()392     private static void openZygoteSocketIfNeeded()
393             throws ZygoteStartFailedEx {
394 
395         int retryCount;
396 
397         if (sPreviousZygoteOpenFailed) {
398             /*
399              * If we've failed before, expect that we'll fail again and
400              * don't pause for retries.
401              */
402             retryCount = 0;
403         } else {
404             retryCount = 10;
405         }
406 
407         /*
408          * See bug #811181: Sometimes runtime can make it up before zygote.
409          * Really, we'd like to do something better to avoid this condition,
410          * but for now just wait a bit...
411          */
412         for (int retry = 0
413                 ; (sZygoteSocket == null) && (retry < (retryCount + 1))
414                 ; retry++ ) {
415 
416             if (retry > 0) {
417                 try {
418                     Log.i("Zygote", "Zygote not up yet, sleeping...");
419                     Thread.sleep(ZYGOTE_RETRY_MILLIS);
420                 } catch (InterruptedException ex) {
421                     // should never happen
422                 }
423             }
424 
425             try {
426                 sZygoteSocket = new LocalSocket();
427 
428                 sZygoteSocket.connect(new LocalSocketAddress(ZYGOTE_SOCKET,
429                         LocalSocketAddress.Namespace.RESERVED));
430 
431                 sZygoteInputStream
432                         = new DataInputStream(sZygoteSocket.getInputStream());
433 
434                 sZygoteWriter =
435                     new BufferedWriter(
436                             new OutputStreamWriter(
437                                     sZygoteSocket.getOutputStream()),
438                             256);
439 
440                 Log.i("Zygote", "Process: zygote socket opened");
441 
442                 sPreviousZygoteOpenFailed = false;
443                 break;
444             } catch (IOException ex) {
445                 if (sZygoteSocket != null) {
446                     try {
447                         sZygoteSocket.close();
448                     } catch (IOException ex2) {
449                         Log.e(LOG_TAG,"I/O exception on close after exception",
450                                 ex2);
451                     }
452                 }
453 
454                 sZygoteSocket = null;
455             }
456         }
457 
458         if (sZygoteSocket == null) {
459             sPreviousZygoteOpenFailed = true;
460             throw new ZygoteStartFailedEx("connect failed");
461         }
462     }
463 
464     /**
465      * Sends an argument list to the zygote process, which starts a new child
466      * and returns the child's pid. Please note: the present implementation
467      * replaces newlines in the argument list with spaces.
468      * @param args argument list
469      * @return An object that describes the result of the attempt to start the process.
470      * @throws ZygoteStartFailedEx if process start failed for any reason
471      */
zygoteSendArgsAndGetResult(ArrayList<String> args)472     private static ProcessStartResult zygoteSendArgsAndGetResult(ArrayList<String> args)
473             throws ZygoteStartFailedEx {
474         openZygoteSocketIfNeeded();
475 
476         try {
477             /**
478              * See com.android.internal.os.ZygoteInit.readArgumentList()
479              * Presently the wire format to the zygote process is:
480              * a) a count of arguments (argc, in essence)
481              * b) a number of newline-separated argument strings equal to count
482              *
483              * After the zygote process reads these it will write the pid of
484              * the child or -1 on failure, followed by boolean to
485              * indicate whether a wrapper process was used.
486              */
487 
488             sZygoteWriter.write(Integer.toString(args.size()));
489             sZygoteWriter.newLine();
490 
491             int sz = args.size();
492             for (int i = 0; i < sz; i++) {
493                 String arg = args.get(i);
494                 if (arg.indexOf('\n') >= 0) {
495                     throw new ZygoteStartFailedEx(
496                             "embedded newlines not allowed");
497                 }
498                 sZygoteWriter.write(arg);
499                 sZygoteWriter.newLine();
500             }
501 
502             sZygoteWriter.flush();
503 
504             // Should there be a timeout on this?
505             ProcessStartResult result = new ProcessStartResult();
506             result.pid = sZygoteInputStream.readInt();
507             if (result.pid < 0) {
508                 throw new ZygoteStartFailedEx("fork() failed");
509             }
510             result.usingWrapper = sZygoteInputStream.readBoolean();
511             return result;
512         } catch (IOException ex) {
513             try {
514                 if (sZygoteSocket != null) {
515                     sZygoteSocket.close();
516                 }
517             } catch (IOException ex2) {
518                 // we're going to fail anyway
519                 Log.e(LOG_TAG,"I/O exception on routine close", ex2);
520             }
521 
522             sZygoteSocket = null;
523 
524             throw new ZygoteStartFailedEx(ex);
525         }
526     }
527 
528     /**
529      * Starts a new process via the zygote mechanism.
530      *
531      * @param processClass Class name whose static main() to run
532      * @param niceName 'nice' process name to appear in ps
533      * @param uid a POSIX uid that the new process should setuid() to
534      * @param gid a POSIX gid that the new process shuold setgid() to
535      * @param gids null-ok; a list of supplementary group IDs that the
536      * new process should setgroup() to.
537      * @param debugFlags Additional flags.
538      * @param targetSdkVersion The target SDK version for the app.
539      * @param extraArgs Additional arguments to supply to the zygote process.
540      * @return An object that describes the result of the attempt to start the process.
541      * @throws ZygoteStartFailedEx if process start failed for any reason
542      */
startViaZygote(final String processClass, final String niceName, final int uid, final int gid, final int[] gids, int debugFlags, int targetSdkVersion, String[] extraArgs)543     private static ProcessStartResult startViaZygote(final String processClass,
544                                   final String niceName,
545                                   final int uid, final int gid,
546                                   final int[] gids,
547                                   int debugFlags, int targetSdkVersion,
548                                   String[] extraArgs)
549                                   throws ZygoteStartFailedEx {
550         synchronized(Process.class) {
551             ArrayList<String> argsForZygote = new ArrayList<String>();
552 
553             // --runtime-init, --setuid=, --setgid=,
554             // and --setgroups= must go first
555             argsForZygote.add("--runtime-init");
556             argsForZygote.add("--setuid=" + uid);
557             argsForZygote.add("--setgid=" + gid);
558             if ((debugFlags & Zygote.DEBUG_ENABLE_JNI_LOGGING) != 0) {
559                 argsForZygote.add("--enable-jni-logging");
560             }
561             if ((debugFlags & Zygote.DEBUG_ENABLE_SAFEMODE) != 0) {
562                 argsForZygote.add("--enable-safemode");
563             }
564             if ((debugFlags & Zygote.DEBUG_ENABLE_DEBUGGER) != 0) {
565                 argsForZygote.add("--enable-debugger");
566             }
567             if ((debugFlags & Zygote.DEBUG_ENABLE_CHECKJNI) != 0) {
568                 argsForZygote.add("--enable-checkjni");
569             }
570             if ((debugFlags & Zygote.DEBUG_ENABLE_ASSERT) != 0) {
571                 argsForZygote.add("--enable-assert");
572             }
573             argsForZygote.add("--target-sdk-version=" + targetSdkVersion);
574 
575             //TODO optionally enable debuger
576             //argsForZygote.add("--enable-debugger");
577 
578             // --setgroups is a comma-separated list
579             if (gids != null && gids.length > 0) {
580                 StringBuilder sb = new StringBuilder();
581                 sb.append("--setgroups=");
582 
583                 int sz = gids.length;
584                 for (int i = 0; i < sz; i++) {
585                     if (i != 0) {
586                         sb.append(',');
587                     }
588                     sb.append(gids[i]);
589                 }
590 
591                 argsForZygote.add(sb.toString());
592             }
593 
594             if (niceName != null) {
595                 argsForZygote.add("--nice-name=" + niceName);
596             }
597 
598             argsForZygote.add(processClass);
599 
600             if (extraArgs != null) {
601                 for (String arg : extraArgs) {
602                     argsForZygote.add(arg);
603                 }
604             }
605 
606             return zygoteSendArgsAndGetResult(argsForZygote);
607         }
608     }
609 
610     /**
611      * Returns elapsed milliseconds of the time this process has run.
612      * @return  Returns the number of milliseconds this process has return.
613      */
getElapsedCpuTime()614     public static final native long getElapsedCpuTime();
615 
616     /**
617      * Returns the identifier of this process, which can be used with
618      * {@link #killProcess} and {@link #sendSignal}.
619      */
myPid()620     public static final native int myPid();
621 
622     /**
623      * Returns the identifier of the calling thread, which be used with
624      * {@link #setThreadPriority(int, int)}.
625      */
myTid()626     public static final native int myTid();
627 
628     /**
629      * Returns the identifier of this process's user.
630      */
myUid()631     public static final native int myUid();
632 
633     /**
634      * Returns whether the current process is in an isolated sandbox.
635      * @hide
636      */
isIsolated()637     public static final boolean isIsolated() {
638         int uid = UserId.getAppId(myUid());
639         return uid >= FIRST_ISOLATED_UID && uid <= LAST_ISOLATED_UID;
640     }
641 
642     /**
643      * Returns the UID assigned to a particular user name, or -1 if there is
644      * none.  If the given string consists of only numbers, it is converted
645      * directly to a uid.
646      */
getUidForName(String name)647     public static final native int getUidForName(String name);
648 
649     /**
650      * Returns the GID assigned to a particular user name, or -1 if there is
651      * none.  If the given string consists of only numbers, it is converted
652      * directly to a gid.
653      */
getGidForName(String name)654     public static final native int getGidForName(String name);
655 
656     /**
657      * Returns a uid for a currently running process.
658      * @param pid the process id
659      * @return the uid of the process, or -1 if the process is not running.
660      * @hide pending API council review
661      */
getUidForPid(int pid)662     public static final int getUidForPid(int pid) {
663         String[] procStatusLabels = { "Uid:" };
664         long[] procStatusValues = new long[1];
665         procStatusValues[0] = -1;
666         Process.readProcLines("/proc/" + pid + "/status", procStatusLabels, procStatusValues);
667         return (int) procStatusValues[0];
668     }
669 
670     /**
671      * Returns the parent process id for a currently running process.
672      * @param pid the process id
673      * @return the parent process id of the process, or -1 if the process is not running.
674      * @hide
675      */
getParentPid(int pid)676     public static final int getParentPid(int pid) {
677         String[] procStatusLabels = { "PPid:" };
678         long[] procStatusValues = new long[1];
679         procStatusValues[0] = -1;
680         Process.readProcLines("/proc/" + pid + "/status", procStatusLabels, procStatusValues);
681         return (int) procStatusValues[0];
682     }
683 
684     /**
685      * Returns the thread group leader id for a currently running thread.
686      * @param tid the thread id
687      * @return the thread group leader id of the thread, or -1 if the thread is not running.
688      *         This is same as what getpid(2) would return if called by tid.
689      * @hide
690      */
getThreadGroupLeader(int tid)691     public static final int getThreadGroupLeader(int tid) {
692         String[] procStatusLabels = { "Tgid:" };
693         long[] procStatusValues = new long[1];
694         procStatusValues[0] = -1;
695         Process.readProcLines("/proc/" + tid + "/status", procStatusLabels, procStatusValues);
696         return (int) procStatusValues[0];
697     }
698 
699     /**
700      * Set the priority of a thread, based on Linux priorities.
701      *
702      * @param tid The identifier of the thread/process to change.
703      * @param priority A Linux priority level, from -20 for highest scheduling
704      * priority to 19 for lowest scheduling priority.
705      *
706      * @throws IllegalArgumentException Throws IllegalArgumentException if
707      * <var>tid</var> does not exist.
708      * @throws SecurityException Throws SecurityException if your process does
709      * not have permission to modify the given thread, or to use the given
710      * priority.
711      */
setThreadPriority(int tid, int priority)712     public static final native void setThreadPriority(int tid, int priority)
713             throws IllegalArgumentException, SecurityException;
714 
715     /**
716      * Call with 'false' to cause future calls to {@link #setThreadPriority(int)} to
717      * throw an exception if passed a background-level thread priority.  This is only
718      * effective if the JNI layer is built with GUARD_THREAD_PRIORITY defined to 1.
719      *
720      * @hide
721      */
setCanSelfBackground(boolean backgroundOk)722     public static final native void setCanSelfBackground(boolean backgroundOk);
723 
724     /**
725      * Sets the scheduling group for a thread.
726      * @hide
727      * @param tid The identifier of the thread to change.
728      * @param group The target group for this thread from THREAD_GROUP_*.
729      *
730      * @throws IllegalArgumentException Throws IllegalArgumentException if
731      * <var>tid</var> does not exist.
732      * @throws SecurityException Throws SecurityException if your process does
733      * not have permission to modify the given thread, or to use the given
734      * priority.
735      * If the thread is a thread group leader, that is it's gettid() == getpid(),
736      * then the other threads in the same thread group are _not_ affected.
737      */
setThreadGroup(int tid, int group)738     public static final native void setThreadGroup(int tid, int group)
739             throws IllegalArgumentException, SecurityException;
740 
741     /**
742      * Sets the scheduling group for a process and all child threads
743      * @hide
744      * @param pid The identifier of the process to change.
745      * @param group The target group for this process from THREAD_GROUP_*.
746      *
747      * @throws IllegalArgumentException Throws IllegalArgumentException if
748      * <var>tid</var> does not exist.
749      * @throws SecurityException Throws SecurityException if your process does
750      * not have permission to modify the given thread, or to use the given
751      * priority.
752      *
753      * group == THREAD_GROUP_DEFAULT means to move all non-background priority
754      * threads to the foreground scheduling group, but to leave background
755      * priority threads alone.  group == THREAD_GROUP_BG_NONINTERACTIVE moves all
756      * threads, regardless of priority, to the background scheduling group.
757      * group == THREAD_GROUP_FOREGROUND is not allowed.
758      */
setProcessGroup(int pid, int group)759     public static final native void setProcessGroup(int pid, int group)
760             throws IllegalArgumentException, SecurityException;
761 
762     /**
763      * Set the priority of the calling thread, based on Linux priorities.  See
764      * {@link #setThreadPriority(int, int)} for more information.
765      *
766      * @param priority A Linux priority level, from -20 for highest scheduling
767      * priority to 19 for lowest scheduling priority.
768      *
769      * @throws IllegalArgumentException Throws IllegalArgumentException if
770      * <var>tid</var> does not exist.
771      * @throws SecurityException Throws SecurityException if your process does
772      * not have permission to modify the given thread, or to use the given
773      * priority.
774      *
775      * @see #setThreadPriority(int, int)
776      */
setThreadPriority(int priority)777     public static final native void setThreadPriority(int priority)
778             throws IllegalArgumentException, SecurityException;
779 
780     /**
781      * Return the current priority of a thread, based on Linux priorities.
782      *
783      * @param tid The identifier of the thread/process to change.
784      *
785      * @return Returns the current priority, as a Linux priority level,
786      * from -20 for highest scheduling priority to 19 for lowest scheduling
787      * priority.
788      *
789      * @throws IllegalArgumentException Throws IllegalArgumentException if
790      * <var>tid</var> does not exist.
791      */
getThreadPriority(int tid)792     public static final native int getThreadPriority(int tid)
793             throws IllegalArgumentException;
794 
795     /**
796      * Set the scheduling policy and priority of a thread, based on Linux.
797      *
798      * @param tid The identifier of the thread/process to change.
799      * @param policy A Linux scheduling policy such as SCHED_OTHER etc.
800      * @param priority A Linux priority level in a range appropriate for the given policy.
801      *
802      * @throws IllegalArgumentException Throws IllegalArgumentException if
803      * <var>tid</var> does not exist, or if <var>priority</var> is out of range for the policy.
804      * @throws SecurityException Throws SecurityException if your process does
805      * not have permission to modify the given thread, or to use the given
806      * scheduling policy or priority.
807      *
808      * {@hide}
809      */
setThreadScheduler(int tid, int policy, int priority)810     public static final native void setThreadScheduler(int tid, int policy, int priority)
811             throws IllegalArgumentException;
812 
813     /**
814      * Determine whether the current environment supports multiple processes.
815      *
816      * @return Returns true if the system can run in multiple processes, else
817      * false if everything is running in a single process.
818      *
819      * @deprecated This method always returns true.  Do not use.
820      */
821     @Deprecated
supportsProcesses()822     public static final boolean supportsProcesses() {
823         return true;
824     }
825 
826     /**
827      * Set the out-of-memory badness adjustment for a process.
828      *
829      * @param pid The process identifier to set.
830      * @param amt Adjustment value -- linux allows -16 to +15.
831      *
832      * @return Returns true if the underlying system supports this
833      *         feature, else false.
834      *
835      * {@hide}
836      */
setOomAdj(int pid, int amt)837     public static final native boolean setOomAdj(int pid, int amt);
838 
839     /**
840      * Change this process's argv[0] parameter.  This can be useful to show
841      * more descriptive information in things like the 'ps' command.
842      *
843      * @param text The new name of this process.
844      *
845      * {@hide}
846      */
setArgV0(String text)847     public static final native void setArgV0(String text);
848 
849     /**
850      * Kill the process with the given PID.
851      * Note that, though this API allows us to request to
852      * kill any process based on its PID, the kernel will
853      * still impose standard restrictions on which PIDs you
854      * are actually able to kill.  Typically this means only
855      * the process running the caller's packages/application
856      * and any additional processes created by that app; packages
857      * sharing a common UID will also be able to kill each
858      * other's processes.
859      */
killProcess(int pid)860     public static final void killProcess(int pid) {
861         sendSignal(pid, SIGNAL_KILL);
862     }
863 
864     /** @hide */
setUid(int uid)865     public static final native int setUid(int uid);
866 
867     /** @hide */
setGid(int uid)868     public static final native int setGid(int uid);
869 
870     /**
871      * Send a signal to the given process.
872      *
873      * @param pid The pid of the target process.
874      * @param signal The signal to send.
875      */
sendSignal(int pid, int signal)876     public static final native void sendSignal(int pid, int signal);
877 
878     /**
879      * @hide
880      * Private impl for avoiding a log message...  DO NOT USE without doing
881      * your own log, or the Android Illuminati will find you some night and
882      * beat you up.
883      */
killProcessQuiet(int pid)884     public static final void killProcessQuiet(int pid) {
885         sendSignalQuiet(pid, SIGNAL_KILL);
886     }
887 
888     /**
889      * @hide
890      * Private impl for avoiding a log message...  DO NOT USE without doing
891      * your own log, or the Android Illuminati will find you some night and
892      * beat you up.
893      */
sendSignalQuiet(int pid, int signal)894     public static final native void sendSignalQuiet(int pid, int signal);
895 
896     /** @hide */
getFreeMemory()897     public static final native long getFreeMemory();
898 
899     /** @hide */
getTotalMemory()900     public static final native long getTotalMemory();
901 
902     /** @hide */
readProcLines(String path, String[] reqFields, long[] outSizes)903     public static final native void readProcLines(String path,
904             String[] reqFields, long[] outSizes);
905 
906     /** @hide */
getPids(String path, int[] lastArray)907     public static final native int[] getPids(String path, int[] lastArray);
908 
909     /** @hide */
910     public static final int PROC_TERM_MASK = 0xff;
911     /** @hide */
912     public static final int PROC_ZERO_TERM = 0;
913     /** @hide */
914     public static final int PROC_SPACE_TERM = (int)' ';
915     /** @hide */
916     public static final int PROC_TAB_TERM = (int)'\t';
917     /** @hide */
918     public static final int PROC_COMBINE = 0x100;
919     /** @hide */
920     public static final int PROC_PARENS = 0x200;
921     /** @hide */
922     public static final int PROC_OUT_STRING = 0x1000;
923     /** @hide */
924     public static final int PROC_OUT_LONG = 0x2000;
925     /** @hide */
926     public static final int PROC_OUT_FLOAT = 0x4000;
927 
928     /** @hide */
readProcFile(String file, int[] format, String[] outStrings, long[] outLongs, float[] outFloats)929     public static final native boolean readProcFile(String file, int[] format,
930             String[] outStrings, long[] outLongs, float[] outFloats);
931 
932     /** @hide */
parseProcLine(byte[] buffer, int startIndex, int endIndex, int[] format, String[] outStrings, long[] outLongs, float[] outFloats)933     public static final native boolean parseProcLine(byte[] buffer, int startIndex,
934             int endIndex, int[] format, String[] outStrings, long[] outLongs, float[] outFloats);
935 
936     /** @hide */
getPidsForCommands(String[] cmds)937     public static final native int[] getPidsForCommands(String[] cmds);
938 
939     /**
940      * Gets the total Pss value for a given process, in bytes.
941      *
942      * @param pid the process to the Pss for
943      * @return the total Pss value for the given process in bytes,
944      *  or -1 if the value cannot be determined
945      * @hide
946      */
getPss(int pid)947     public static final native long getPss(int pid);
948 
949     /**
950      * Specifies the outcome of having started a process.
951      * @hide
952      */
953     public static final class ProcessStartResult {
954         /**
955          * The PID of the newly started process.
956          * Always >= 0.  (If the start failed, an exception will have been thrown instead.)
957          */
958         public int pid;
959 
960         /**
961          * True if the process was started with a wrapper attached.
962          */
963         public boolean usingWrapper;
964     }
965 }
966