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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 import libcore.io.Libcore;
     31 
     32 /*package*/ class ZygoteStartFailedEx extends Exception {
     33     /**
     34      * Something prevented the zygote process startup from happening normally
     35      */
     36 
     37     ZygoteStartFailedEx() {};
     38     ZygoteStartFailedEx(String s) {super(s);}
     39     ZygoteStartFailedEx(Throwable cause) {super(cause);}
     40 }
     41 
     42 /**
     43  * Tools for managing OS processes.
     44  */
     45 public class Process {
     46     private static final String LOG_TAG = "Process";
     47 
     48     private static final String ZYGOTE_SOCKET = "zygote";
     49 
     50     /**
     51      * Name of a process for running the platform's media services.
     52      * {@hide}
     53      */
     54     public static final String ANDROID_SHARED_MEDIA = "com.android.process.media";
     55 
     56     /**
     57      * Name of the process that Google content providers can share.
     58      * {@hide}
     59      */
     60     public static final String GOOGLE_SHARED_APP_CONTENT = "com.google.process.content";
     61 
     62     /**
     63      * Defines the UID/GID under which system code runs.
     64      */
     65     public static final int SYSTEM_UID = 1000;
     66 
     67     /**
     68      * Defines the UID/GID under which the telephony code runs.
     69      */
     70     public static final int PHONE_UID = 1001;
     71 
     72     /**
     73      * Defines the UID/GID for the user shell.
     74      * @hide
     75      */
     76     public static final int SHELL_UID = 2000;
     77 
     78     /**
     79      * Defines the UID/GID for the log group.
     80      * @hide
     81      */
     82     public static final int LOG_UID = 1007;
     83 
     84     /**
     85      * Defines the UID/GID for the WIFI supplicant process.
     86      * @hide
     87      */
     88     public static final int WIFI_UID = 1010;
     89 
     90     /**
     91      * Defines the UID/GID for the mediaserver process.
     92      * @hide
     93      */
     94     public static final int MEDIA_UID = 1013;
     95 
     96     /**
     97      * Defines the UID/GID for the DRM process.
     98      * @hide
     99      */
    100     public static final int DRM_UID = 1019;
    101 
    102     /**
    103      * Defines the UID/GID for the group that controls VPN services.
    104      * @hide
    105      */
    106     public static final int VPN_UID = 1016;
    107 
    108     /**
    109      * Defines the UID/GID for the NFC service process.
    110      * @hide
    111      */
    112     public static final int NFC_UID = 1027;
    113 
    114     /**
    115      * Defines the UID/GID for the Bluetooth service process.
    116      * @hide
    117      */
    118     public static final int BLUETOOTH_UID = 1002;
    119 
    120     /**
    121      * Defines the GID for the group that allows write access to the internal media storage.
    122      * @hide
    123      */
    124     public static final int MEDIA_RW_GID = 1023;
    125 
    126     /**
    127      * Access to installed package details
    128      * @hide
    129      */
    130     public static final int PACKAGE_INFO_GID = 1032;
    131 
    132     /**
    133      * Defines the start of a range of UIDs (and GIDs), going from this
    134      * number to {@link #LAST_APPLICATION_UID} that are reserved for assigning
    135      * to applications.
    136      */
    137     public static final int FIRST_APPLICATION_UID = 10000;
    138 
    139     /**
    140      * Last of application-specific UIDs starting at
    141      * {@link #FIRST_APPLICATION_UID}.
    142      */
    143     public static final int LAST_APPLICATION_UID = 19999;
    144 
    145     /**
    146      * First uid used for fully isolated sandboxed processes (with no permissions of their own)
    147      * @hide
    148      */
    149     public static final int FIRST_ISOLATED_UID = 99000;
    150 
    151     /**
    152      * Last uid used for fully isolated sandboxed processes (with no permissions of their own)
    153      * @hide
    154      */
    155     public static final int LAST_ISOLATED_UID = 99999;
    156 
    157     /**
    158      * First gid for applications to share resources. Used when forward-locking
    159      * is enabled but all UserHandles need to be able to read the resources.
    160      * @hide
    161      */
    162     public static final int FIRST_SHARED_APPLICATION_GID = 50000;
    163 
    164     /**
    165      * Last gid for applications to share resources. Used when forward-locking
    166      * is enabled but all UserHandles need to be able to read the resources.
    167      * @hide
    168      */
    169     public static final int LAST_SHARED_APPLICATION_GID = 59999;
    170 
    171     /**
    172      * Standard priority of application threads.
    173      * Use with {@link #setThreadPriority(int)} and
    174      * {@link #setThreadPriority(int, int)}, <b>not</b> with the normal
    175      * {@link java.lang.Thread} class.
    176      */
    177     public static final int THREAD_PRIORITY_DEFAULT = 0;
    178 
    179     /*
    180      * ***************************************
    181      * ** Keep in sync with utils/threads.h **
    182      * ***************************************
    183      */
    184 
    185     /**
    186      * Lowest available thread priority.  Only for those who really, really
    187      * don't want to run if anything else is happening.
    188      * Use with {@link #setThreadPriority(int)} and
    189      * {@link #setThreadPriority(int, int)}, <b>not</b> with the normal
    190      * {@link java.lang.Thread} class.
    191      */
    192     public static final int THREAD_PRIORITY_LOWEST = 19;
    193 
    194     /**
    195      * Standard priority background threads.  This gives your thread a slightly
    196      * lower than normal priority, so that it will have less chance of impacting
    197      * the responsiveness of the user interface.
    198      * Use with {@link #setThreadPriority(int)} and
    199      * {@link #setThreadPriority(int, int)}, <b>not</b> with the normal
    200      * {@link java.lang.Thread} class.
    201      */
    202     public static final int THREAD_PRIORITY_BACKGROUND = 10;
    203 
    204     /**
    205      * Standard priority of threads that are currently running a user interface
    206      * that the user is interacting with.  Applications can not normally
    207      * change to this priority; the system will automatically adjust your
    208      * application threads as the user moves through the UI.
    209      * Use with {@link #setThreadPriority(int)} and
    210      * {@link #setThreadPriority(int, int)}, <b>not</b> with the normal
    211      * {@link java.lang.Thread} class.
    212      */
    213     public static final int THREAD_PRIORITY_FOREGROUND = -2;
    214 
    215     /**
    216      * Standard priority of system display threads, involved in updating
    217      * the user interface.  Applications can not
    218      * normally change to this priority.
    219      * Use with {@link #setThreadPriority(int)} and
    220      * {@link #setThreadPriority(int, int)}, <b>not</b> with the normal
    221      * {@link java.lang.Thread} class.
    222      */
    223     public static final int THREAD_PRIORITY_DISPLAY = -4;
    224 
    225     /**
    226      * Standard priority of the most important display threads, for compositing
    227      * the screen and retrieving input events.  Applications can not normally
    228      * 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_DISPLAY = -8;
    234 
    235     /**
    236      * Standard priority of audio threads.  Applications can not normally
    237      * change to this priority.
    238      * Use with {@link #setThreadPriority(int)} and
    239      * {@link #setThreadPriority(int, int)}, <b>not</b> with the normal
    240      * {@link java.lang.Thread} class.
    241      */
    242     public static final int THREAD_PRIORITY_AUDIO = -16;
    243 
    244     /**
    245      * Standard priority of the most important audio threads.
    246      * Applications can not normally change to this priority.
    247      * Use with {@link #setThreadPriority(int)} and
    248      * {@link #setThreadPriority(int, int)}, <b>not</b> with the normal
    249      * {@link java.lang.Thread} class.
    250      */
    251     public static final int THREAD_PRIORITY_URGENT_AUDIO = -19;
    252 
    253     /**
    254      * Minimum increment to make a priority more favorable.
    255      */
    256     public static final int THREAD_PRIORITY_MORE_FAVORABLE = -1;
    257 
    258     /**
    259      * Minimum increment to make a priority less favorable.
    260      */
    261     public static final int THREAD_PRIORITY_LESS_FAVORABLE = +1;
    262 
    263     /**
    264      * Default scheduling policy
    265      * @hide
    266      */
    267     public static final int SCHED_OTHER = 0;
    268 
    269     /**
    270      * First-In First-Out scheduling policy
    271      * @hide
    272      */
    273     public static final int SCHED_FIFO = 1;
    274 
    275     /**
    276      * Round-Robin scheduling policy
    277      * @hide
    278      */
    279     public static final int SCHED_RR = 2;
    280 
    281     /**
    282      * Batch scheduling policy
    283      * @hide
    284      */
    285     public static final int SCHED_BATCH = 3;
    286 
    287     /**
    288      * Idle scheduling policy
    289      * @hide
    290      */
    291     public static final int SCHED_IDLE = 5;
    292 
    293     // Keep in sync with SP_* constants of enum type SchedPolicy
    294     // declared in system/core/include/cutils/sched_policy.h,
    295     // except THREAD_GROUP_DEFAULT does not correspond to any SP_* value.
    296 
    297     /**
    298      * Default thread group -
    299      * has meaning with setProcessGroup() only, cannot be used with setThreadGroup().
    300      * When used with setProcessGroup(), the group of each thread in the process
    301      * is conditionally changed based on that thread's current priority, as follows:
    302      * threads with priority numerically less than THREAD_PRIORITY_BACKGROUND
    303      * are moved to foreground thread group.  All other threads are left unchanged.
    304      * @hide
    305      */
    306     public static final int THREAD_GROUP_DEFAULT = -1;
    307 
    308     /**
    309      * Background thread group - All threads in
    310      * this group are scheduled with a reduced share of the CPU.
    311      * Value is same as constant SP_BACKGROUND of enum SchedPolicy.
    312      * FIXME rename to THREAD_GROUP_BACKGROUND.
    313      * @hide
    314      */
    315     public static final int THREAD_GROUP_BG_NONINTERACTIVE = 0;
    316 
    317     /**
    318      * Foreground thread group - All threads in
    319      * this group are scheduled with a normal share of the CPU.
    320      * Value is same as constant SP_FOREGROUND of enum SchedPolicy.
    321      * Not used at this level.
    322      * @hide
    323      **/
    324     private static final int THREAD_GROUP_FOREGROUND = 1;
    325 
    326     /**
    327      * System thread group.
    328      * @hide
    329      **/
    330     public static final int THREAD_GROUP_SYSTEM = 2;
    331 
    332     /**
    333      * Application audio thread group.
    334      * @hide
    335      **/
    336     public static final int THREAD_GROUP_AUDIO_APP = 3;
    337 
    338     /**
    339      * System audio thread group.
    340      * @hide
    341      **/
    342     public static final int THREAD_GROUP_AUDIO_SYS = 4;
    343 
    344     public static final int SIGNAL_QUIT = 3;
    345     public static final int SIGNAL_KILL = 9;
    346     public static final int SIGNAL_USR1 = 10;
    347 
    348     // State for communicating with zygote process
    349 
    350     static LocalSocket sZygoteSocket;
    351     static DataInputStream sZygoteInputStream;
    352     static BufferedWriter sZygoteWriter;
    353 
    354     /** true if previous zygote open failed */
    355     static boolean sPreviousZygoteOpenFailed;
    356 
    357     /**
    358      * Start a new process.
    359      *
    360      * <p>If processes are enabled, a new process is created and the
    361      * static main() function of a <var>processClass</var> is executed there.
    362      * The process will continue running after this function returns.
    363      *
    364      * <p>If processes are not enabled, a new thread in the caller's
    365      * process is created and main() of <var>processClass</var> called there.
    366      *
    367      * <p>The niceName parameter, if not an empty string, is a custom name to
    368      * give to the process instead of using processClass.  This allows you to
    369      * make easily identifyable processes even if you are using the same base
    370      * <var>processClass</var> to start them.
    371      *
    372      * @param processClass The class to use as the process's main entry
    373      *                     point.
    374      * @param niceName A more readable name to use for the process.
    375      * @param uid The user-id under which the process will run.
    376      * @param gid The group-id under which the process will run.
    377      * @param gids Additional group-ids associated with the process.
    378      * @param debugFlags Additional flags.
    379      * @param targetSdkVersion The target SDK version for the app.
    380      * @param seInfo null-ok SE Android information for the new process.
    381      * @param zygoteArgs Additional arguments to supply to the zygote process.
    382      *
    383      * @return An object that describes the result of the attempt to start the process.
    384      * @throws RuntimeException on fatal start failure
    385      *
    386      * {@hide}
    387      */
    388     public static final ProcessStartResult start(final String processClass,
    389                                   final String niceName,
    390                                   int uid, int gid, int[] gids,
    391                                   int debugFlags, int mountExternal,
    392                                   int targetSdkVersion,
    393                                   String seInfo,
    394                                   String[] zygoteArgs) {
    395         try {
    396             return startViaZygote(processClass, niceName, uid, gid, gids,
    397                     debugFlags, mountExternal, targetSdkVersion, seInfo, zygoteArgs);
    398         } catch (ZygoteStartFailedEx ex) {
    399             Log.e(LOG_TAG,
    400                     "Starting VM process through Zygote failed");
    401             throw new RuntimeException(
    402                     "Starting VM process through Zygote failed", ex);
    403         }
    404     }
    405 
    406     /** retry interval for opening a zygote socket */
    407     static final int ZYGOTE_RETRY_MILLIS = 500;
    408 
    409     /**
    410      * Tries to open socket to Zygote process if not already open. If
    411      * already open, does nothing.  May block and retry.
    412      */
    413     private static void openZygoteSocketIfNeeded()
    414             throws ZygoteStartFailedEx {
    415 
    416         int retryCount;
    417 
    418         if (sPreviousZygoteOpenFailed) {
    419             /*
    420              * If we've failed before, expect that we'll fail again and
    421              * don't pause for retries.
    422              */
    423             retryCount = 0;
    424         } else {
    425             retryCount = 10;
    426         }
    427 
    428         /*
    429          * See bug #811181: Sometimes runtime can make it up before zygote.
    430          * Really, we'd like to do something better to avoid this condition,
    431          * but for now just wait a bit...
    432          */
    433         for (int retry = 0
    434                 ; (sZygoteSocket == null) && (retry < (retryCount + 1))
    435                 ; retry++ ) {
    436 
    437             if (retry > 0) {
    438                 try {
    439                     Log.i("Zygote", "Zygote not up yet, sleeping...");
    440                     Thread.sleep(ZYGOTE_RETRY_MILLIS);
    441                 } catch (InterruptedException ex) {
    442                     // should never happen
    443                 }
    444             }
    445 
    446             try {
    447                 sZygoteSocket = new LocalSocket();
    448 
    449                 sZygoteSocket.connect(new LocalSocketAddress(ZYGOTE_SOCKET,
    450                         LocalSocketAddress.Namespace.RESERVED));
    451 
    452                 sZygoteInputStream
    453                         = new DataInputStream(sZygoteSocket.getInputStream());
    454 
    455                 sZygoteWriter =
    456                     new BufferedWriter(
    457                             new OutputStreamWriter(
    458                                     sZygoteSocket.getOutputStream()),
    459                             256);
    460 
    461                 Log.i("Zygote", "Process: zygote socket opened");
    462 
    463                 sPreviousZygoteOpenFailed = false;
    464                 break;
    465             } catch (IOException ex) {
    466                 if (sZygoteSocket != null) {
    467                     try {
    468                         sZygoteSocket.close();
    469                     } catch (IOException ex2) {
    470                         Log.e(LOG_TAG,"I/O exception on close after exception",
    471                                 ex2);
    472                     }
    473                 }
    474 
    475                 sZygoteSocket = null;
    476             }
    477         }
    478 
    479         if (sZygoteSocket == null) {
    480             sPreviousZygoteOpenFailed = true;
    481             throw new ZygoteStartFailedEx("connect failed");
    482         }
    483     }
    484 
    485     /**
    486      * Sends an argument list to the zygote process, which starts a new child
    487      * and returns the child's pid. Please note: the present implementation
    488      * replaces newlines in the argument list with spaces.
    489      * @param args argument list
    490      * @return An object that describes the result of the attempt to start the process.
    491      * @throws ZygoteStartFailedEx if process start failed for any reason
    492      */
    493     private static ProcessStartResult zygoteSendArgsAndGetResult(ArrayList<String> args)
    494             throws ZygoteStartFailedEx {
    495         openZygoteSocketIfNeeded();
    496 
    497         try {
    498             /**
    499              * See com.android.internal.os.ZygoteInit.readArgumentList()
    500              * Presently the wire format to the zygote process is:
    501              * a) a count of arguments (argc, in essence)
    502              * b) a number of newline-separated argument strings equal to count
    503              *
    504              * After the zygote process reads these it will write the pid of
    505              * the child or -1 on failure, followed by boolean to
    506              * indicate whether a wrapper process was used.
    507              */
    508 
    509             sZygoteWriter.write(Integer.toString(args.size()));
    510             sZygoteWriter.newLine();
    511 
    512             int sz = args.size();
    513             for (int i = 0; i < sz; i++) {
    514                 String arg = args.get(i);
    515                 if (arg.indexOf('\n') >= 0) {
    516                     throw new ZygoteStartFailedEx(
    517                             "embedded newlines not allowed");
    518                 }
    519                 sZygoteWriter.write(arg);
    520                 sZygoteWriter.newLine();
    521             }
    522 
    523             sZygoteWriter.flush();
    524 
    525             // Should there be a timeout on this?
    526             ProcessStartResult result = new ProcessStartResult();
    527             result.pid = sZygoteInputStream.readInt();
    528             if (result.pid < 0) {
    529                 throw new ZygoteStartFailedEx("fork() failed");
    530             }
    531             result.usingWrapper = sZygoteInputStream.readBoolean();
    532             return result;
    533         } catch (IOException ex) {
    534             try {
    535                 if (sZygoteSocket != null) {
    536                     sZygoteSocket.close();
    537                 }
    538             } catch (IOException ex2) {
    539                 // we're going to fail anyway
    540                 Log.e(LOG_TAG,"I/O exception on routine close", ex2);
    541             }
    542 
    543             sZygoteSocket = null;
    544 
    545             throw new ZygoteStartFailedEx(ex);
    546         }
    547     }
    548 
    549     /**
    550      * Starts a new process via the zygote mechanism.
    551      *
    552      * @param processClass Class name whose static main() to run
    553      * @param niceName 'nice' process name to appear in ps
    554      * @param uid a POSIX uid that the new process should setuid() to
    555      * @param gid a POSIX gid that the new process shuold setgid() to
    556      * @param gids null-ok; a list of supplementary group IDs that the
    557      * new process should setgroup() to.
    558      * @param debugFlags Additional flags.
    559      * @param targetSdkVersion The target SDK version for the app.
    560      * @param seInfo null-ok SE Android information for the new process.
    561      * @param extraArgs Additional arguments to supply to the zygote process.
    562      * @return An object that describes the result of the attempt to start the process.
    563      * @throws ZygoteStartFailedEx if process start failed for any reason
    564      */
    565     private static ProcessStartResult startViaZygote(final String processClass,
    566                                   final String niceName,
    567                                   final int uid, final int gid,
    568                                   final int[] gids,
    569                                   int debugFlags, int mountExternal,
    570                                   int targetSdkVersion,
    571                                   String seInfo,
    572                                   String[] extraArgs)
    573                                   throws ZygoteStartFailedEx {
    574         synchronized(Process.class) {
    575             ArrayList<String> argsForZygote = new ArrayList<String>();
    576 
    577             // --runtime-init, --setuid=, --setgid=,
    578             // and --setgroups= must go first
    579             argsForZygote.add("--runtime-init");
    580             argsForZygote.add("--setuid=" + uid);
    581             argsForZygote.add("--setgid=" + gid);
    582             if ((debugFlags & Zygote.DEBUG_ENABLE_JNI_LOGGING) != 0) {
    583                 argsForZygote.add("--enable-jni-logging");
    584             }
    585             if ((debugFlags & Zygote.DEBUG_ENABLE_SAFEMODE) != 0) {
    586                 argsForZygote.add("--enable-safemode");
    587             }
    588             if ((debugFlags & Zygote.DEBUG_ENABLE_DEBUGGER) != 0) {
    589                 argsForZygote.add("--enable-debugger");
    590             }
    591             if ((debugFlags & Zygote.DEBUG_ENABLE_CHECKJNI) != 0) {
    592                 argsForZygote.add("--enable-checkjni");
    593             }
    594             if ((debugFlags & Zygote.DEBUG_ENABLE_ASSERT) != 0) {
    595                 argsForZygote.add("--enable-assert");
    596             }
    597             if (mountExternal == Zygote.MOUNT_EXTERNAL_MULTIUSER) {
    598                 argsForZygote.add("--mount-external-multiuser");
    599             } else if (mountExternal == Zygote.MOUNT_EXTERNAL_MULTIUSER_ALL) {
    600                 argsForZygote.add("--mount-external-multiuser-all");
    601             }
    602             argsForZygote.add("--target-sdk-version=" + targetSdkVersion);
    603 
    604             //TODO optionally enable debuger
    605             //argsForZygote.add("--enable-debugger");
    606 
    607             // --setgroups is a comma-separated list
    608             if (gids != null && gids.length > 0) {
    609                 StringBuilder sb = new StringBuilder();
    610                 sb.append("--setgroups=");
    611 
    612                 int sz = gids.length;
    613                 for (int i = 0; i < sz; i++) {
    614                     if (i != 0) {
    615                         sb.append(',');
    616                     }
    617                     sb.append(gids[i]);
    618                 }
    619 
    620                 argsForZygote.add(sb.toString());
    621             }
    622 
    623             if (niceName != null) {
    624                 argsForZygote.add("--nice-name=" + niceName);
    625             }
    626 
    627             if (seInfo != null) {
    628                 argsForZygote.add("--seinfo=" + seInfo);
    629             }
    630 
    631             argsForZygote.add(processClass);
    632 
    633             if (extraArgs != null) {
    634                 for (String arg : extraArgs) {
    635                     argsForZygote.add(arg);
    636                 }
    637             }
    638 
    639             return zygoteSendArgsAndGetResult(argsForZygote);
    640         }
    641     }
    642 
    643     /**
    644      * Returns elapsed milliseconds of the time this process has run.
    645      * @return  Returns the number of milliseconds this process has return.
    646      */
    647     public static final native long getElapsedCpuTime();
    648 
    649     /**
    650      * Returns the identifier of this process, which can be used with
    651      * {@link #killProcess} and {@link #sendSignal}.
    652      */
    653     public static final int myPid() {
    654         return Libcore.os.getpid();
    655     }
    656 
    657     /**
    658      * Returns the identifier of this process' parent.
    659      * @hide
    660      */
    661     public static final int myPpid() {
    662         return Libcore.os.getppid();
    663     }
    664 
    665     /**
    666      * Returns the identifier of the calling thread, which be used with
    667      * {@link #setThreadPriority(int, int)}.
    668      */
    669     public static final int myTid() {
    670         return Libcore.os.gettid();
    671     }
    672 
    673     /**
    674      * Returns the identifier of this process's uid.  This is the kernel uid
    675      * that the process is running under, which is the identity of its
    676      * app-specific sandbox.  It is different from {@link #myUserHandle} in that
    677      * a uid identifies a specific app sandbox in a specific user.
    678      */
    679     public static final int myUid() {
    680         return Libcore.os.getuid();
    681     }
    682 
    683     /**
    684      * Returns this process's user handle.  This is the
    685      * user the process is running under.  It is distinct from
    686      * {@link #myUid()} in that a particular user will have multiple
    687      * distinct apps running under it each with their own uid.
    688      */
    689     public static final UserHandle myUserHandle() {
    690         return new UserHandle(UserHandle.getUserId(myUid()));
    691     }
    692 
    693     /**
    694      * Returns whether the current process is in an isolated sandbox.
    695      * @hide
    696      */
    697     public static final boolean isIsolated() {
    698         int uid = UserHandle.getAppId(myUid());
    699         return uid >= FIRST_ISOLATED_UID && uid <= LAST_ISOLATED_UID;
    700     }
    701 
    702     /**
    703      * Returns the UID assigned to a particular user name, or -1 if there is
    704      * none.  If the given string consists of only numbers, it is converted
    705      * directly to a uid.
    706      */
    707     public static final native int getUidForName(String name);
    708 
    709     /**
    710      * Returns the GID assigned to a particular user name, or -1 if there is
    711      * none.  If the given string consists of only numbers, it is converted
    712      * directly to a gid.
    713      */
    714     public static final native int getGidForName(String name);
    715 
    716     /**
    717      * Returns a uid for a currently running process.
    718      * @param pid the process id
    719      * @return the uid of the process, or -1 if the process is not running.
    720      * @hide pending API council review
    721      */
    722     public static final int getUidForPid(int pid) {
    723         String[] procStatusLabels = { "Uid:" };
    724         long[] procStatusValues = new long[1];
    725         procStatusValues[0] = -1;
    726         Process.readProcLines("/proc/" + pid + "/status", procStatusLabels, procStatusValues);
    727         return (int) procStatusValues[0];
    728     }
    729 
    730     /**
    731      * Returns the parent process id for a currently running process.
    732      * @param pid the process id
    733      * @return the parent process id of the process, or -1 if the process is not running.
    734      * @hide
    735      */
    736     public static final int getParentPid(int pid) {
    737         String[] procStatusLabels = { "PPid:" };
    738         long[] procStatusValues = new long[1];
    739         procStatusValues[0] = -1;
    740         Process.readProcLines("/proc/" + pid + "/status", procStatusLabels, procStatusValues);
    741         return (int) procStatusValues[0];
    742     }
    743 
    744     /**
    745      * Returns the thread group leader id for a currently running thread.
    746      * @param tid the thread id
    747      * @return the thread group leader id of the thread, or -1 if the thread is not running.
    748      *         This is same as what getpid(2) would return if called by tid.
    749      * @hide
    750      */
    751     public static final int getThreadGroupLeader(int tid) {
    752         String[] procStatusLabels = { "Tgid:" };
    753         long[] procStatusValues = new long[1];
    754         procStatusValues[0] = -1;
    755         Process.readProcLines("/proc/" + tid + "/status", procStatusLabels, procStatusValues);
    756         return (int) procStatusValues[0];
    757     }
    758 
    759     /**
    760      * Set the priority of a thread, based on Linux priorities.
    761      *
    762      * @param tid The identifier of the thread/process to change.
    763      * @param priority A Linux priority level, from -20 for highest scheduling
    764      * priority to 19 for lowest scheduling priority.
    765      *
    766      * @throws IllegalArgumentException Throws IllegalArgumentException if
    767      * <var>tid</var> does not exist.
    768      * @throws SecurityException Throws SecurityException if your process does
    769      * not have permission to modify the given thread, or to use the given
    770      * priority.
    771      */
    772     public static final native void setThreadPriority(int tid, int priority)
    773             throws IllegalArgumentException, SecurityException;
    774 
    775     /**
    776      * Call with 'false' to cause future calls to {@link #setThreadPriority(int)} to
    777      * throw an exception if passed a background-level thread priority.  This is only
    778      * effective if the JNI layer is built with GUARD_THREAD_PRIORITY defined to 1.
    779      *
    780      * @hide
    781      */
    782     public static final native void setCanSelfBackground(boolean backgroundOk);
    783 
    784     /**
    785      * Sets the scheduling group for a thread.
    786      * @hide
    787      * @param tid The identifier of the thread to change.
    788      * @param group The target group for this thread from THREAD_GROUP_*.
    789      *
    790      * @throws IllegalArgumentException Throws IllegalArgumentException if
    791      * <var>tid</var> does not exist.
    792      * @throws SecurityException Throws SecurityException if your process does
    793      * not have permission to modify the given thread, or to use the given
    794      * priority.
    795      * If the thread is a thread group leader, that is it's gettid() == getpid(),
    796      * then the other threads in the same thread group are _not_ affected.
    797      */
    798     public static final native void setThreadGroup(int tid, int group)
    799             throws IllegalArgumentException, SecurityException;
    800 
    801     /**
    802      * Sets the scheduling group for a process and all child threads
    803      * @hide
    804      * @param pid The identifier of the process to change.
    805      * @param group The target group for this process from THREAD_GROUP_*.
    806      *
    807      * @throws IllegalArgumentException Throws IllegalArgumentException if
    808      * <var>tid</var> does not exist.
    809      * @throws SecurityException Throws SecurityException if your process does
    810      * not have permission to modify the given thread, or to use the given
    811      * priority.
    812      *
    813      * group == THREAD_GROUP_DEFAULT means to move all non-background priority
    814      * threads to the foreground scheduling group, but to leave background
    815      * priority threads alone.  group == THREAD_GROUP_BG_NONINTERACTIVE moves all
    816      * threads, regardless of priority, to the background scheduling group.
    817      * group == THREAD_GROUP_FOREGROUND is not allowed.
    818      */
    819     public static final native void setProcessGroup(int pid, int group)
    820             throws IllegalArgumentException, SecurityException;
    821 
    822     /**
    823      * Return the scheduling group of requested process.
    824      *
    825      * @hide
    826      */
    827     public static final native int getProcessGroup(int pid)
    828             throws IllegalArgumentException, SecurityException;
    829 
    830     /**
    831      * Set the priority of the calling thread, based on Linux priorities.  See
    832      * {@link #setThreadPriority(int, int)} for more information.
    833      *
    834      * @param priority A Linux priority level, from -20 for highest scheduling
    835      * priority to 19 for lowest scheduling priority.
    836      *
    837      * @throws IllegalArgumentException Throws IllegalArgumentException if
    838      * <var>tid</var> does not exist.
    839      * @throws SecurityException Throws SecurityException if your process does
    840      * not have permission to modify the given thread, or to use the given
    841      * priority.
    842      *
    843      * @see #setThreadPriority(int, int)
    844      */
    845     public static final native void setThreadPriority(int priority)
    846             throws IllegalArgumentException, SecurityException;
    847 
    848     /**
    849      * Return the current priority of a thread, based on Linux priorities.
    850      *
    851      * @param tid The identifier of the thread/process to change.
    852      *
    853      * @return Returns the current priority, as a Linux priority level,
    854      * from -20 for highest scheduling priority to 19 for lowest scheduling
    855      * priority.
    856      *
    857      * @throws IllegalArgumentException Throws IllegalArgumentException if
    858      * <var>tid</var> does not exist.
    859      */
    860     public static final native int getThreadPriority(int tid)
    861             throws IllegalArgumentException;
    862 
    863     /**
    864      * Set the scheduling policy and priority of a thread, based on Linux.
    865      *
    866      * @param tid The identifier of the thread/process to change.
    867      * @param policy A Linux scheduling policy such as SCHED_OTHER etc.
    868      * @param priority A Linux priority level in a range appropriate for the given policy.
    869      *
    870      * @throws IllegalArgumentException Throws IllegalArgumentException if
    871      * <var>tid</var> does not exist, or if <var>priority</var> is out of range for the policy.
    872      * @throws SecurityException Throws SecurityException if your process does
    873      * not have permission to modify the given thread, or to use the given
    874      * scheduling policy or priority.
    875      *
    876      * {@hide}
    877      */
    878     public static final native void setThreadScheduler(int tid, int policy, int priority)
    879             throws IllegalArgumentException;
    880 
    881     /**
    882      * Determine whether the current environment supports multiple processes.
    883      *
    884      * @return Returns true if the system can run in multiple processes, else
    885      * false if everything is running in a single process.
    886      *
    887      * @deprecated This method always returns true.  Do not use.
    888      */
    889     @Deprecated
    890     public static final boolean supportsProcesses() {
    891         return true;
    892     }
    893 
    894     /**
    895      * Set the out-of-memory badness adjustment for a process.
    896      *
    897      * @param pid The process identifier to set.
    898      * @param amt Adjustment value -- linux allows -16 to +15.
    899      *
    900      * @return Returns true if the underlying system supports this
    901      *         feature, else false.
    902      *
    903      * {@hide}
    904      */
    905     public static final native boolean setOomAdj(int pid, int amt);
    906 
    907     /**
    908      * Adjust the swappiness level for a process.
    909      *
    910      * @param pid The process identifier to set.
    911      * @param is_increased Whether swappiness should be increased or default.
    912      *
    913      * @return Returns true if the underlying system supports this
    914      *         feature, else false.
    915      *
    916      * {@hide}
    917      */
    918     public static final native boolean setSwappiness(int pid, boolean is_increased);
    919 
    920     /**
    921      * Change this process's argv[0] parameter.  This can be useful to show
    922      * more descriptive information in things like the 'ps' command.
    923      *
    924      * @param text The new name of this process.
    925      *
    926      * {@hide}
    927      */
    928     public static final native void setArgV0(String text);
    929 
    930     /**
    931      * Kill the process with the given PID.
    932      * Note that, though this API allows us to request to
    933      * kill any process based on its PID, the kernel will
    934      * still impose standard restrictions on which PIDs you
    935      * are actually able to kill.  Typically this means only
    936      * the process running the caller's packages/application
    937      * and any additional processes created by that app; packages
    938      * sharing a common UID will also be able to kill each
    939      * other's processes.
    940      */
    941     public static final void killProcess(int pid) {
    942         sendSignal(pid, SIGNAL_KILL);
    943     }
    944 
    945     /** @hide */
    946     public static final native int setUid(int uid);
    947 
    948     /** @hide */
    949     public static final native int setGid(int uid);
    950 
    951     /**
    952      * Send a signal to the given process.
    953      *
    954      * @param pid The pid of the target process.
    955      * @param signal The signal to send.
    956      */
    957     public static final native void sendSignal(int pid, int signal);
    958 
    959     /**
    960      * @hide
    961      * Private impl for avoiding a log message...  DO NOT USE without doing
    962      * your own log, or the Android Illuminati will find you some night and
    963      * beat you up.
    964      */
    965     public static final void killProcessQuiet(int pid) {
    966         sendSignalQuiet(pid, SIGNAL_KILL);
    967     }
    968 
    969     /**
    970      * @hide
    971      * Private impl for avoiding a log message...  DO NOT USE without doing
    972      * your own log, or the Android Illuminati will find you some night and
    973      * beat you up.
    974      */
    975     public static final native void sendSignalQuiet(int pid, int signal);
    976 
    977     /** @hide */
    978     public static final native long getFreeMemory();
    979 
    980     /** @hide */
    981     public static final native long getTotalMemory();
    982 
    983     /** @hide */
    984     public static final native void readProcLines(String path,
    985             String[] reqFields, long[] outSizes);
    986 
    987     /** @hide */
    988     public static final native int[] getPids(String path, int[] lastArray);
    989 
    990     /** @hide */
    991     public static final int PROC_TERM_MASK = 0xff;
    992     /** @hide */
    993     public static final int PROC_ZERO_TERM = 0;
    994     /** @hide */
    995     public static final int PROC_SPACE_TERM = (int)' ';
    996     /** @hide */
    997     public static final int PROC_TAB_TERM = (int)'\t';
    998     /** @hide */
    999     public static final int PROC_COMBINE = 0x100;
   1000     /** @hide */
   1001     public static final int PROC_PARENS = 0x200;
   1002     /** @hide */
   1003     public static final int PROC_QUOTES = 0x400;
   1004     /** @hide */
   1005     public static final int PROC_OUT_STRING = 0x1000;
   1006     /** @hide */
   1007     public static final int PROC_OUT_LONG = 0x2000;
   1008     /** @hide */
   1009     public static final int PROC_OUT_FLOAT = 0x4000;
   1010 
   1011     /** @hide */
   1012     public static final native boolean readProcFile(String file, int[] format,
   1013             String[] outStrings, long[] outLongs, float[] outFloats);
   1014 
   1015     /** @hide */
   1016     public static final native boolean parseProcLine(byte[] buffer, int startIndex,
   1017             int endIndex, int[] format, String[] outStrings, long[] outLongs, float[] outFloats);
   1018 
   1019     /** @hide */
   1020     public static final native int[] getPidsForCommands(String[] cmds);
   1021 
   1022     /**
   1023      * Gets the total Pss value for a given process, in bytes.
   1024      *
   1025      * @param pid the process to the Pss for
   1026      * @return the total Pss value for the given process in bytes,
   1027      *  or -1 if the value cannot be determined
   1028      * @hide
   1029      */
   1030     public static final native long getPss(int pid);
   1031 
   1032     /**
   1033      * Specifies the outcome of having started a process.
   1034      * @hide
   1035      */
   1036     public static final class ProcessStartResult {
   1037         /**
   1038          * The PID of the newly started process.
   1039          * Always >= 0.  (If the start failed, an exception will have been thrown instead.)
   1040          */
   1041         public int pid;
   1042 
   1043         /**
   1044          * True if the process was started with a wrapper attached.
   1045          */
   1046         public boolean usingWrapper;
   1047     }
   1048 }
   1049