Process.java revision f1b56449f58963e4f0473d5e26961f68c31759f4
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 17package android.os; 18 19import android.net.LocalSocketAddress; 20import android.net.LocalSocket; 21import android.util.Log; 22import dalvik.system.Zygote; 23 24import java.io.BufferedWriter; 25import java.io.DataInputStream; 26import java.io.IOException; 27import java.io.OutputStreamWriter; 28import java.util.ArrayList; 29 30/*package*/ class ZygoteStartFailedEx extends Exception { 31 /** 32 * Something prevented the zygote process startup from happening normally 33 */ 34 35 ZygoteStartFailedEx() {}; 36 ZygoteStartFailedEx(String s) {super(s);} 37 ZygoteStartFailedEx(Throwable cause) {super(cause);} 38} 39 40/** 41 * Tools for managing OS processes. 42 */ 43public 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 GID for the group that allows write access to the SD card. 96 * @hide 97 */ 98 public static final int SDCARD_RW_GID = 1015; 99 100 /** 101 * Defines the UID/GID for the group that controls VPN services. 102 * @hide 103 */ 104 public static final int VPN_UID = 1016; 105 106 /** 107 * Defines the UID/GID for the NFC service process. 108 * @hide 109 */ 110 public static final int NFC_UID = 1027; 111 112 /** 113 * Defines the GID for the group that allows write access to the internal media storage. 114 * @hide 115 */ 116 public static final int MEDIA_RW_GID = 1023; 117 118 /** 119 * Defines the start of a range of UIDs (and GIDs), going from this 120 * number to {@link #LAST_APPLICATION_UID} that are reserved for assigning 121 * to applications. 122 */ 123 public static final int FIRST_APPLICATION_UID = 10000; 124 /** 125 * Last of application-specific UIDs starting at 126 * {@link #FIRST_APPLICATION_UID}. 127 */ 128 public static final int LAST_APPLICATION_UID = 19999; 129 130 /** 131 * First uid used for fully isolated sandboxed processes (with no permissions of their own) 132 * @hide 133 */ 134 public static final int FIRST_ISOLATED_UID = 99000; 135 136 /** 137 * Last uid used for fully isolated sandboxed processes (with no permissions of their own) 138 * @hide 139 */ 140 public static final int LAST_ISOLATED_UID = 99999; 141 142 /** 143 * Defines a secondary group id for access to the bluetooth hardware. 144 */ 145 public static final int BLUETOOTH_GID = 2000; 146 147 /** 148 * Standard priority of application threads. 149 * Use with {@link #setThreadPriority(int)} and 150 * {@link #setThreadPriority(int, int)}, <b>not</b> with the normal 151 * {@link java.lang.Thread} class. 152 */ 153 public static final int THREAD_PRIORITY_DEFAULT = 0; 154 155 /* 156 * *************************************** 157 * ** Keep in sync with utils/threads.h ** 158 * *************************************** 159 */ 160 161 /** 162 * Lowest available thread priority. Only for those who really, really 163 * don't want to run if anything else is happening. 164 * Use with {@link #setThreadPriority(int)} and 165 * {@link #setThreadPriority(int, int)}, <b>not</b> with the normal 166 * {@link java.lang.Thread} class. 167 */ 168 public static final int THREAD_PRIORITY_LOWEST = 19; 169 170 /** 171 * Standard priority background threads. This gives your thread a slightly 172 * lower than normal priority, so that it will have less chance of impacting 173 * the responsiveness of the user interface. 174 * Use with {@link #setThreadPriority(int)} and 175 * {@link #setThreadPriority(int, int)}, <b>not</b> with the normal 176 * {@link java.lang.Thread} class. 177 */ 178 public static final int THREAD_PRIORITY_BACKGROUND = 10; 179 180 /** 181 * Standard priority of threads that are currently running a user interface 182 * that the user is interacting with. Applications can not normally 183 * change to this priority; the system will automatically adjust your 184 * application threads as the user moves through the UI. 185 * Use with {@link #setThreadPriority(int)} and 186 * {@link #setThreadPriority(int, int)}, <b>not</b> with the normal 187 * {@link java.lang.Thread} class. 188 */ 189 public static final int THREAD_PRIORITY_FOREGROUND = -2; 190 191 /** 192 * Standard priority of system display threads, involved in updating 193 * the user interface. Applications can not 194 * normally change to this priority. 195 * Use with {@link #setThreadPriority(int)} and 196 * {@link #setThreadPriority(int, int)}, <b>not</b> with the normal 197 * {@link java.lang.Thread} class. 198 */ 199 public static final int THREAD_PRIORITY_DISPLAY = -4; 200 201 /** 202 * Standard priority of the most important display threads, for compositing 203 * the screen and retrieving input events. Applications can not normally 204 * change to this priority. 205 * Use with {@link #setThreadPriority(int)} and 206 * {@link #setThreadPriority(int, int)}, <b>not</b> with the normal 207 * {@link java.lang.Thread} class. 208 */ 209 public static final int THREAD_PRIORITY_URGENT_DISPLAY = -8; 210 211 /** 212 * Standard priority of audio threads. Applications can not normally 213 * change to this priority. 214 * Use with {@link #setThreadPriority(int)} and 215 * {@link #setThreadPriority(int, int)}, <b>not</b> with the normal 216 * {@link java.lang.Thread} class. 217 */ 218 public static final int THREAD_PRIORITY_AUDIO = -16; 219 220 /** 221 * Standard priority of the most important audio threads. 222 * Applications can not normally change to this priority. 223 * Use with {@link #setThreadPriority(int)} and 224 * {@link #setThreadPriority(int, int)}, <b>not</b> with the normal 225 * {@link java.lang.Thread} class. 226 */ 227 public static final int THREAD_PRIORITY_URGENT_AUDIO = -19; 228 229 /** 230 * Minimum increment to make a priority more favorable. 231 */ 232 public static final int THREAD_PRIORITY_MORE_FAVORABLE = -1; 233 234 /** 235 * Minimum increment to make a priority less favorable. 236 */ 237 public static final int THREAD_PRIORITY_LESS_FAVORABLE = +1; 238 239 /** 240 * Default scheduling policy 241 * @hide 242 */ 243 public static final int SCHED_OTHER = 0; 244 245 /** 246 * First-In First-Out scheduling policy 247 * @hide 248 */ 249 public static final int SCHED_FIFO = 1; 250 251 /** 252 * Round-Robin scheduling policy 253 * @hide 254 */ 255 public static final int SCHED_RR = 2; 256 257 /** 258 * Batch scheduling policy 259 * @hide 260 */ 261 public static final int SCHED_BATCH = 3; 262 263 /** 264 * Idle scheduling policy 265 * @hide 266 */ 267 public static final int SCHED_IDLE = 5; 268 269 // Keep in sync with SP_* constants of enum type SchedPolicy 270 // declared in system/core/include/cutils/sched_policy.h, 271 // except THREAD_GROUP_DEFAULT does not correspond to any SP_* value. 272 273 /** 274 * Default thread group - 275 * has meaning with setProcessGroup() only, cannot be used with setThreadGroup(). 276 * When used with setProcessGroup(), the group of each thread in the process 277 * is conditionally changed based on that thread's current priority, as follows: 278 * threads with priority numerically less than THREAD_PRIORITY_BACKGROUND 279 * are moved to foreground thread group. All other threads are left unchanged. 280 * @hide 281 */ 282 public static final int THREAD_GROUP_DEFAULT = -1; 283 284 /** 285 * Background thread group - All threads in 286 * this group are scheduled with a reduced share of the CPU. 287 * Value is same as constant SP_BACKGROUND of enum SchedPolicy. 288 * FIXME rename to THREAD_GROUP_BACKGROUND. 289 * @hide 290 */ 291 public static final int THREAD_GROUP_BG_NONINTERACTIVE = 0; 292 293 /** 294 * Foreground thread group - All threads in 295 * this group are scheduled with a normal share of the CPU. 296 * Value is same as constant SP_FOREGROUND of enum SchedPolicy. 297 * Not used at this level. 298 * @hide 299 **/ 300 private static final int THREAD_GROUP_FOREGROUND = 1; 301 302 public static final int SIGNAL_QUIT = 3; 303 public static final int SIGNAL_KILL = 9; 304 public static final int SIGNAL_USR1 = 10; 305 306 // State for communicating with zygote process 307 308 static LocalSocket sZygoteSocket; 309 static DataInputStream sZygoteInputStream; 310 static BufferedWriter sZygoteWriter; 311 312 /** true if previous zygote open failed */ 313 static boolean sPreviousZygoteOpenFailed; 314 315 /** 316 * Start a new process. 317 * 318 * <p>If processes are enabled, a new process is created and the 319 * static main() function of a <var>processClass</var> is executed there. 320 * The process will continue running after this function returns. 321 * 322 * <p>If processes are not enabled, a new thread in the caller's 323 * process is created and main() of <var>processClass</var> called there. 324 * 325 * <p>The niceName parameter, if not an empty string, is a custom name to 326 * give to the process instead of using processClass. This allows you to 327 * make easily identifyable processes even if you are using the same base 328 * <var>processClass</var> to start them. 329 * 330 * @param processClass The class to use as the process's main entry 331 * point. 332 * @param niceName A more readable name to use for the process. 333 * @param uid The user-id under which the process will run. 334 * @param gid The group-id under which the process will run. 335 * @param gids Additional group-ids associated with the process. 336 * @param debugFlags Additional flags. 337 * @param targetSdkVersion The target SDK version for the app. 338 * @param zygoteArgs Additional arguments to supply to the zygote process. 339 * 340 * @return An object that describes the result of the attempt to start the process. 341 * @throws RuntimeException on fatal start failure 342 * 343 * {@hide} 344 */ 345 public static final ProcessStartResult start(final String processClass, 346 final String niceName, 347 int uid, int gid, int[] gids, 348 int debugFlags, int targetSdkVersion, 349 String[] zygoteArgs) { 350 try { 351 return startViaZygote(processClass, niceName, uid, gid, gids, 352 debugFlags, targetSdkVersion, zygoteArgs); 353 } catch (ZygoteStartFailedEx ex) { 354 Log.e(LOG_TAG, 355 "Starting VM process through Zygote failed"); 356 throw new RuntimeException( 357 "Starting VM process through Zygote failed", ex); 358 } 359 } 360 361 /** retry interval for opening a zygote socket */ 362 static final int ZYGOTE_RETRY_MILLIS = 500; 363 364 /** 365 * Tries to open socket to Zygote process if not already open. If 366 * already open, does nothing. May block and retry. 367 */ 368 private static void openZygoteSocketIfNeeded() 369 throws ZygoteStartFailedEx { 370 371 int retryCount; 372 373 if (sPreviousZygoteOpenFailed) { 374 /* 375 * If we've failed before, expect that we'll fail again and 376 * don't pause for retries. 377 */ 378 retryCount = 0; 379 } else { 380 retryCount = 10; 381 } 382 383 /* 384 * See bug #811181: Sometimes runtime can make it up before zygote. 385 * Really, we'd like to do something better to avoid this condition, 386 * but for now just wait a bit... 387 */ 388 for (int retry = 0 389 ; (sZygoteSocket == null) && (retry < (retryCount + 1)) 390 ; retry++ ) { 391 392 if (retry > 0) { 393 try { 394 Log.i("Zygote", "Zygote not up yet, sleeping..."); 395 Thread.sleep(ZYGOTE_RETRY_MILLIS); 396 } catch (InterruptedException ex) { 397 // should never happen 398 } 399 } 400 401 try { 402 sZygoteSocket = new LocalSocket(); 403 404 sZygoteSocket.connect(new LocalSocketAddress(ZYGOTE_SOCKET, 405 LocalSocketAddress.Namespace.RESERVED)); 406 407 sZygoteInputStream 408 = new DataInputStream(sZygoteSocket.getInputStream()); 409 410 sZygoteWriter = 411 new BufferedWriter( 412 new OutputStreamWriter( 413 sZygoteSocket.getOutputStream()), 414 256); 415 416 Log.i("Zygote", "Process: zygote socket opened"); 417 418 sPreviousZygoteOpenFailed = false; 419 break; 420 } catch (IOException ex) { 421 if (sZygoteSocket != null) { 422 try { 423 sZygoteSocket.close(); 424 } catch (IOException ex2) { 425 Log.e(LOG_TAG,"I/O exception on close after exception", 426 ex2); 427 } 428 } 429 430 sZygoteSocket = null; 431 } 432 } 433 434 if (sZygoteSocket == null) { 435 sPreviousZygoteOpenFailed = true; 436 throw new ZygoteStartFailedEx("connect failed"); 437 } 438 } 439 440 /** 441 * Sends an argument list to the zygote process, which starts a new child 442 * and returns the child's pid. Please note: the present implementation 443 * replaces newlines in the argument list with spaces. 444 * @param args argument list 445 * @return An object that describes the result of the attempt to start the process. 446 * @throws ZygoteStartFailedEx if process start failed for any reason 447 */ 448 private static ProcessStartResult zygoteSendArgsAndGetResult(ArrayList<String> args) 449 throws ZygoteStartFailedEx { 450 openZygoteSocketIfNeeded(); 451 452 try { 453 /** 454 * See com.android.internal.os.ZygoteInit.readArgumentList() 455 * Presently the wire format to the zygote process is: 456 * a) a count of arguments (argc, in essence) 457 * b) a number of newline-separated argument strings equal to count 458 * 459 * After the zygote process reads these it will write the pid of 460 * the child or -1 on failure, followed by boolean to 461 * indicate whether a wrapper process was used. 462 */ 463 464 sZygoteWriter.write(Integer.toString(args.size())); 465 sZygoteWriter.newLine(); 466 467 int sz = args.size(); 468 for (int i = 0; i < sz; i++) { 469 String arg = args.get(i); 470 if (arg.indexOf('\n') >= 0) { 471 throw new ZygoteStartFailedEx( 472 "embedded newlines not allowed"); 473 } 474 sZygoteWriter.write(arg); 475 sZygoteWriter.newLine(); 476 } 477 478 sZygoteWriter.flush(); 479 480 // Should there be a timeout on this? 481 ProcessStartResult result = new ProcessStartResult(); 482 result.pid = sZygoteInputStream.readInt(); 483 if (result.pid < 0) { 484 throw new ZygoteStartFailedEx("fork() failed"); 485 } 486 result.usingWrapper = sZygoteInputStream.readBoolean(); 487 return result; 488 } catch (IOException ex) { 489 try { 490 if (sZygoteSocket != null) { 491 sZygoteSocket.close(); 492 } 493 } catch (IOException ex2) { 494 // we're going to fail anyway 495 Log.e(LOG_TAG,"I/O exception on routine close", ex2); 496 } 497 498 sZygoteSocket = null; 499 500 throw new ZygoteStartFailedEx(ex); 501 } 502 } 503 504 /** 505 * Starts a new process via the zygote mechanism. 506 * 507 * @param processClass Class name whose static main() to run 508 * @param niceName 'nice' process name to appear in ps 509 * @param uid a POSIX uid that the new process should setuid() to 510 * @param gid a POSIX gid that the new process shuold setgid() to 511 * @param gids null-ok; a list of supplementary group IDs that the 512 * new process should setgroup() to. 513 * @param debugFlags Additional flags. 514 * @param targetSdkVersion The target SDK version for the app. 515 * @param extraArgs Additional arguments to supply to the zygote process. 516 * @return An object that describes the result of the attempt to start the process. 517 * @throws ZygoteStartFailedEx if process start failed for any reason 518 */ 519 private static ProcessStartResult startViaZygote(final String processClass, 520 final String niceName, 521 final int uid, final int gid, 522 final int[] gids, 523 int debugFlags, int targetSdkVersion, 524 String[] extraArgs) 525 throws ZygoteStartFailedEx { 526 synchronized(Process.class) { 527 ArrayList<String> argsForZygote = new ArrayList<String>(); 528 529 // --runtime-init, --setuid=, --setgid=, 530 // and --setgroups= must go first 531 argsForZygote.add("--runtime-init"); 532 argsForZygote.add("--setuid=" + uid); 533 argsForZygote.add("--setgid=" + gid); 534 if ((debugFlags & Zygote.DEBUG_ENABLE_JNI_LOGGING) != 0) { 535 argsForZygote.add("--enable-jni-logging"); 536 } 537 if ((debugFlags & Zygote.DEBUG_ENABLE_SAFEMODE) != 0) { 538 argsForZygote.add("--enable-safemode"); 539 } 540 if ((debugFlags & Zygote.DEBUG_ENABLE_DEBUGGER) != 0) { 541 argsForZygote.add("--enable-debugger"); 542 } 543 if ((debugFlags & Zygote.DEBUG_ENABLE_CHECKJNI) != 0) { 544 argsForZygote.add("--enable-checkjni"); 545 } 546 if ((debugFlags & Zygote.DEBUG_ENABLE_ASSERT) != 0) { 547 argsForZygote.add("--enable-assert"); 548 } 549 argsForZygote.add("--target-sdk-version=" + targetSdkVersion); 550 551 //TODO optionally enable debuger 552 //argsForZygote.add("--enable-debugger"); 553 554 // --setgroups is a comma-separated list 555 if (gids != null && gids.length > 0) { 556 StringBuilder sb = new StringBuilder(); 557 sb.append("--setgroups="); 558 559 int sz = gids.length; 560 for (int i = 0; i < sz; i++) { 561 if (i != 0) { 562 sb.append(','); 563 } 564 sb.append(gids[i]); 565 } 566 567 argsForZygote.add(sb.toString()); 568 } 569 570 if (niceName != null) { 571 argsForZygote.add("--nice-name=" + niceName); 572 } 573 574 argsForZygote.add(processClass); 575 576 if (extraArgs != null) { 577 for (String arg : extraArgs) { 578 argsForZygote.add(arg); 579 } 580 } 581 582 return zygoteSendArgsAndGetResult(argsForZygote); 583 } 584 } 585 586 /** 587 * Returns elapsed milliseconds of the time this process has run. 588 * @return Returns the number of milliseconds this process has return. 589 */ 590 public static final native long getElapsedCpuTime(); 591 592 /** 593 * Returns the identifier of this process, which can be used with 594 * {@link #killProcess} and {@link #sendSignal}. 595 */ 596 public static final native int myPid(); 597 598 /** 599 * Returns the identifier of the calling thread, which be used with 600 * {@link #setThreadPriority(int, int)}. 601 */ 602 public static final native int myTid(); 603 604 /** 605 * Returns the identifier of this process's user. 606 */ 607 public static final native int myUid(); 608 609 /** 610 * Returns whether the current process is in an isolated sandbox. 611 * @hide 612 */ 613 public static final boolean isIsolated() { 614 int uid = UserId.getAppId(myUid()); 615 return uid >= FIRST_ISOLATED_UID && uid <= LAST_ISOLATED_UID; 616 } 617 618 /** 619 * Returns the UID assigned to a particular user name, or -1 if there is 620 * none. If the given string consists of only numbers, it is converted 621 * directly to a uid. 622 */ 623 public static final native int getUidForName(String name); 624 625 /** 626 * Returns the GID assigned to a particular user name, or -1 if there is 627 * none. If the given string consists of only numbers, it is converted 628 * directly to a gid. 629 */ 630 public static final native int getGidForName(String name); 631 632 /** 633 * Returns a uid for a currently running process. 634 * @param pid the process id 635 * @return the uid of the process, or -1 if the process is not running. 636 * @hide pending API council review 637 */ 638 public static final int getUidForPid(int pid) { 639 String[] procStatusLabels = { "Uid:" }; 640 long[] procStatusValues = new long[1]; 641 procStatusValues[0] = -1; 642 Process.readProcLines("/proc/" + pid + "/status", procStatusLabels, procStatusValues); 643 return (int) procStatusValues[0]; 644 } 645 646 /** 647 * Returns the parent process id for a currently running process. 648 * @param pid the process id 649 * @return the parent process id of the process, or -1 if the process is not running. 650 * @hide 651 */ 652 public static final int getParentPid(int pid) { 653 String[] procStatusLabels = { "PPid:" }; 654 long[] procStatusValues = new long[1]; 655 procStatusValues[0] = -1; 656 Process.readProcLines("/proc/" + pid + "/status", procStatusLabels, procStatusValues); 657 return (int) procStatusValues[0]; 658 } 659 660 /** 661 * Set the priority of a thread, based on Linux priorities. 662 * 663 * @param tid The identifier of the thread/process to change. 664 * @param priority A Linux priority level, from -20 for highest scheduling 665 * priority to 19 for lowest scheduling priority. 666 * 667 * @throws IllegalArgumentException Throws IllegalArgumentException if 668 * <var>tid</var> does not exist. 669 * @throws SecurityException Throws SecurityException if your process does 670 * not have permission to modify the given thread, or to use the given 671 * priority. 672 */ 673 public static final native void setThreadPriority(int tid, int priority) 674 throws IllegalArgumentException, SecurityException; 675 676 /** 677 * Call with 'false' to cause future calls to {@link #setThreadPriority(int)} to 678 * throw an exception if passed a background-level thread priority. This is only 679 * effective if the JNI layer is built with GUARD_THREAD_PRIORITY defined to 1. 680 * 681 * @hide 682 */ 683 public static final native void setCanSelfBackground(boolean backgroundOk); 684 685 /** 686 * Sets the scheduling group for a thread. 687 * @hide 688 * @param tid The identifier of the thread to change. 689 * @param group The target group for this thread from THREAD_GROUP_*. 690 * 691 * @throws IllegalArgumentException Throws IllegalArgumentException if 692 * <var>tid</var> does not exist. 693 * @throws SecurityException Throws SecurityException if your process does 694 * not have permission to modify the given thread, or to use the given 695 * priority. 696 * If the thread is a thread group leader, that is it's gettid() == getpid(), 697 * then the other threads in the same thread group are _not_ affected. 698 */ 699 public static final native void setThreadGroup(int tid, int group) 700 throws IllegalArgumentException, SecurityException; 701 702 /** 703 * Sets the scheduling group for a process and all child threads 704 * @hide 705 * @param pid The identifier of the process to change. 706 * @param group The target group for this process from THREAD_GROUP_*. 707 * 708 * @throws IllegalArgumentException Throws IllegalArgumentException if 709 * <var>tid</var> does not exist. 710 * @throws SecurityException Throws SecurityException if your process does 711 * not have permission to modify the given thread, or to use the given 712 * priority. 713 * 714 * group == THREAD_GROUP_DEFAULT means to move all non-background priority 715 * threads to the foreground scheduling group, but to leave background 716 * priority threads alone. group == THREAD_GROUP_BG_NONINTERACTIVE moves all 717 * threads, regardless of priority, to the background scheduling group. 718 * group == THREAD_GROUP_FOREGROUND is not allowed. 719 */ 720 public static final native void setProcessGroup(int pid, int group) 721 throws IllegalArgumentException, SecurityException; 722 723 /** 724 * Set the priority of the calling thread, based on Linux priorities. See 725 * {@link #setThreadPriority(int, int)} for more information. 726 * 727 * @param priority A Linux priority level, from -20 for highest scheduling 728 * priority to 19 for lowest scheduling priority. 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 * 736 * @see #setThreadPriority(int, int) 737 */ 738 public static final native void setThreadPriority(int priority) 739 throws IllegalArgumentException, SecurityException; 740 741 /** 742 * Return the current priority of a thread, based on Linux priorities. 743 * 744 * @param tid The identifier of the thread/process to change. 745 * 746 * @return Returns the current priority, as a Linux priority level, 747 * from -20 for highest scheduling priority to 19 for lowest scheduling 748 * priority. 749 * 750 * @throws IllegalArgumentException Throws IllegalArgumentException if 751 * <var>tid</var> does not exist. 752 */ 753 public static final native int getThreadPriority(int tid) 754 throws IllegalArgumentException; 755 756 /** 757 * Set the scheduling policy and priority of a thread, based on Linux. 758 * 759 * @param tid The identifier of the thread/process to change. 760 * @param policy A Linux scheduling policy such as SCHED_OTHER etc. 761 * @param priority A Linux priority level in a range appropriate for the given policy. 762 * 763 * @throws IllegalArgumentException Throws IllegalArgumentException if 764 * <var>tid</var> does not exist, or if <var>priority</var> is out of range for the policy. 765 * @throws SecurityException Throws SecurityException if your process does 766 * not have permission to modify the given thread, or to use the given 767 * scheduling policy or priority. 768 * 769 * {@hide} 770 */ 771 public static final native void setThreadScheduler(int tid, int policy, int priority) 772 throws IllegalArgumentException; 773 774 /** 775 * Determine whether the current environment supports multiple processes. 776 * 777 * @return Returns true if the system can run in multiple processes, else 778 * false if everything is running in a single process. 779 * 780 * @deprecated This method always returns true. Do not use. 781 */ 782 @Deprecated 783 public static final boolean supportsProcesses() { 784 return true; 785 } 786 787 /** 788 * Set the out-of-memory badness adjustment for a process. 789 * 790 * @param pid The process identifier to set. 791 * @param amt Adjustment value -- linux allows -16 to +15. 792 * 793 * @return Returns true if the underlying system supports this 794 * feature, else false. 795 * 796 * {@hide} 797 */ 798 public static final native boolean setOomAdj(int pid, int amt); 799 800 /** 801 * Change this process's argv[0] parameter. This can be useful to show 802 * more descriptive information in things like the 'ps' command. 803 * 804 * @param text The new name of this process. 805 * 806 * {@hide} 807 */ 808 public static final native void setArgV0(String text); 809 810 /** 811 * Kill the process with the given PID. 812 * Note that, though this API allows us to request to 813 * kill any process based on its PID, the kernel will 814 * still impose standard restrictions on which PIDs you 815 * are actually able to kill. Typically this means only 816 * the process running the caller's packages/application 817 * and any additional processes created by that app; packages 818 * sharing a common UID will also be able to kill each 819 * other's processes. 820 */ 821 public static final void killProcess(int pid) { 822 sendSignal(pid, SIGNAL_KILL); 823 } 824 825 /** @hide */ 826 public static final native int setUid(int uid); 827 828 /** @hide */ 829 public static final native int setGid(int uid); 830 831 /** 832 * Send a signal to the given process. 833 * 834 * @param pid The pid of the target process. 835 * @param signal The signal to send. 836 */ 837 public static final native void sendSignal(int pid, int signal); 838 839 /** 840 * @hide 841 * Private impl for avoiding a log message... DO NOT USE without doing 842 * your own log, or the Android Illuminati will find you some night and 843 * beat you up. 844 */ 845 public static final void killProcessQuiet(int pid) { 846 sendSignalQuiet(pid, SIGNAL_KILL); 847 } 848 849 /** 850 * @hide 851 * Private impl for avoiding a log message... DO NOT USE without doing 852 * your own log, or the Android Illuminati will find you some night and 853 * beat you up. 854 */ 855 public static final native void sendSignalQuiet(int pid, int signal); 856 857 /** @hide */ 858 public static final native long getFreeMemory(); 859 860 /** @hide */ 861 public static final native void readProcLines(String path, 862 String[] reqFields, long[] outSizes); 863 864 /** @hide */ 865 public static final native int[] getPids(String path, int[] lastArray); 866 867 /** @hide */ 868 public static final int PROC_TERM_MASK = 0xff; 869 /** @hide */ 870 public static final int PROC_ZERO_TERM = 0; 871 /** @hide */ 872 public static final int PROC_SPACE_TERM = (int)' '; 873 /** @hide */ 874 public static final int PROC_TAB_TERM = (int)'\t'; 875 /** @hide */ 876 public static final int PROC_COMBINE = 0x100; 877 /** @hide */ 878 public static final int PROC_PARENS = 0x200; 879 /** @hide */ 880 public static final int PROC_OUT_STRING = 0x1000; 881 /** @hide */ 882 public static final int PROC_OUT_LONG = 0x2000; 883 /** @hide */ 884 public static final int PROC_OUT_FLOAT = 0x4000; 885 886 /** @hide */ 887 public static final native boolean readProcFile(String file, int[] format, 888 String[] outStrings, long[] outLongs, float[] outFloats); 889 890 /** @hide */ 891 public static final native boolean parseProcLine(byte[] buffer, int startIndex, 892 int endIndex, int[] format, String[] outStrings, long[] outLongs, float[] outFloats); 893 894 /** 895 * Gets the total Pss value for a given process, in bytes. 896 * 897 * @param pid the process to the Pss for 898 * @return the total Pss value for the given process in bytes, 899 * or -1 if the value cannot be determined 900 * @hide 901 */ 902 public static final native long getPss(int pid); 903 904 /** 905 * Specifies the outcome of having started a process. 906 * @hide 907 */ 908 public static final class ProcessStartResult { 909 /** 910 * The PID of the newly started process. 911 * Always >= 0. (If the start failed, an exception will have been thrown instead.) 912 */ 913 public int pid; 914 915 /** 916 * True if the process was started with a wrapper attached. 917 */ 918 public boolean usingWrapper; 919 } 920} 921