src/threads/threads-common.c

   1 /* src/threads/threads-common.c - machine independent thread functions
   2
   3    Copyright (C) 2007, 2008
   4    CACAOVM - Verein zur Foerderung der freien virtuellen Maschine CACAO
   5
   6    This file is part of CACAO.
   7
   8    This program is free software; you can redistribute it and/or
   9    modify it under the terms of the GNU General Public License as
  10    published by the Free Software Foundation; either version 2, or (at
  11    your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful, but
  14    WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16    General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program; if not, write to the Free Software
  20    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  21    02110-1301, USA.
  22
  23 */
  24
  25
  26 #include "config.h"
  27
  28 #include <assert.h>
  29 #include <stdint.h>
  30 #include <unistd.h>
  31
  32 #include "vm/types.h"
  33
  34 #include "mm/memory.h"
  35
  36 #include "native/jni.h"
  37 #include "native/llni.h"
  38
  39 #include "native/include/java_lang_Object.h"
  40 #include "native/include/java_lang_String.h"
  41 #include "native/include/java_lang_Thread.h"
  42
  43 #if defined(WITH_CLASSPATH_GNU)
  44 # include "native/include/java_lang_Throwable.h"
  45 # include "native/include/java_lang_VMThread.h"
  46 #endif
  47
  48 #include "threads/critical.h"
  49 #include "threads/lock-common.h"
  50 #include "threads/threadlist.h"
  51 #include "threads/threads-common.h"
  52
  53 #include "toolbox/list.h"
  54
  55 #include "vm/builtin.h"
  56 #include "vm/stringlocal.h"
  57 #include "vm/vm.h"
  58
  59 #include "vm/jit/stacktrace.h"
  60
  61 #include "vmcore/class.h"
  62 #include "vmcore/options.h"
  63
  64 #if defined(ENABLE_STATISTICS)
  65 # include "vmcore/statistics.h"
  66 #endif
  67
  68 #include "vmcore/utf8.h"
  69
  70
  71 /* global variables ***********************************************************/
  72
  73 #if defined(__LINUX__)
  74 /* XXX Remove for exact-GC. */
  75 bool threads_pthreads_implementation_nptl;
  76 #endif
  77
  78
  79 /* threads_preinit *************************************************************
  80
  81    Do some early initialization of stuff required.
  82
  83 *******************************************************************************/
  84
  85 void threads_preinit(void)
  86 {
  87         threadobject *mainthread;
  88 #if defined(__LINUX__) && defined(_CS_GNU_LIBPTHREAD_VERSION)
  89         char         *pathbuf;
  90         size_t        len;
  91 #endif
  92
  93         TRACESUBSYSTEMINITIALIZATION("threads_preinit");
  94
  95 #if defined(__LINUX__)
  96         /* XXX Remove for exact-GC. */
  97
  98         /* On Linux we need to check the pthread implementation. */
  99
 100         /* _CS_GNU_LIBPTHREAD_VERSION (GNU C library only; since glibc 2.3.2) */
 101         /* If the glibc is a pre-2.3.2 version, we fall back to
 102            linuxthreads. */
 103
 104 # if defined(_CS_GNU_LIBPTHREAD_VERSION)
 105         len = confstr(_CS_GNU_LIBPTHREAD_VERSION, NULL, (size_t) 0);
 106
 107         /* Some systems return as length 0 (maybe cross-compilation
 108            related).  In this case we also fall back to linuxthreads. */
 109
 110         if (len > 0) {
 111                 pathbuf = MNEW(char, len);
 112
 113                 (void) confstr(_CS_GNU_LIBPTHREAD_VERSION, pathbuf, len);
 114
 115                 if (strstr(pathbuf, "NPTL") != NULL)
 116                         threads_pthreads_implementation_nptl = true;
 117                 else
 118                         threads_pthreads_implementation_nptl = false;
 119         }
 120         else
 121                 threads_pthreads_implementation_nptl = false;
 122 # else
 123         threads_pthreads_implementation_nptl = false;
 124 # endif
 125 #endif
 126
 127         /* Initialize the threads implementation (sets the thinlock on the
 128            main thread). */
 129
 130         threads_impl_preinit();
 131
 132         /* create internal thread data-structure for the main thread */
 133
 134         mainthread = threads_thread_new();
 135
 136         /* thread is a Java thread and running */
 137
 138         mainthread->flags |= THREAD_FLAG_JAVA;
 139         mainthread->state = THREAD_STATE_RUNNABLE;
 140
 141         /* store the internal thread data-structure in the TSD */
 142
 143         threads_set_current_threadobject(mainthread);
 144 }
 145
 146
 147 /* threads_thread_new **********************************************************
 148
 149    Allocates and initializes an internal thread data-structure and
 150    adds it to the threads list.
 151
 152 *******************************************************************************/
 153
 154 threadobject *threads_thread_new(void)
 155 {
 156         int32_t         index;
 157         threadobject   *t;
 158
 159         /* lock the threads-lists */
 160
 161         threads_list_lock();
 162
 163         index = threadlist_get_free_index();
 164
 165         /* Allocate a thread data structure. */
 166
 167         /* First, try to get one from the free-list. */
 168
 169         t = threadlist_free_first();
 170
 171         if (t != NULL) {
 172                 /* Remove from free list. */
 173
 174                 threadlist_free_remove(t);
 175
 176                 /* Equivalent of MZERO on the else path */
 177
 178                 threads_impl_thread_clear(t);
 179         }
 180         else {
 181 #if defined(ENABLE_GC_BOEHM)
 182                 t = GCNEW_UNCOLLECTABLE(threadobject, 1);
 183 #else
 184                 t = NEW(threadobject);
 185 #endif
 186
 187 #if defined(ENABLE_STATISTICS)
 188                 if (opt_stat)
 189                         size_threadobject += sizeof(threadobject);
 190 #endif
 191
 192                 /* Clear memory. */
 193
 194                 MZERO(t, threadobject, 1);
 195
 196 #if defined(ENABLE_GC_CACAO)
 197                 /* Register reference to java.lang.Thread with the GC. */
 198                 /* FIXME is it ok to do this only once? */
 199
 200                 gc_reference_register(&(t->object), GC_REFTYPE_THREADOBJECT);
 201                 gc_reference_register(&(t->_exceptionptr), GC_REFTYPE_THREADOBJECT);
 202 #endif
 203
 204                 /* Initialize the implementation-specific bits. */
 205
 206                 threads_impl_thread_init(t);
 207         }
 208
 209         /* Pre-compute the thinlock-word. */
 210
 211         assert(index != 0);
 212
 213         t->index     = index;
 214         t->thinlock  = lock_pre_compute_thinlock(t->index);
 215         t->flags     = 0;
 216         t->state     = THREAD_STATE_NEW;
 217
 218 #if defined(ENABLE_GC_CACAO)
 219         t->flags    |= THREAD_FLAG_IN_NATIVE;
 220 #endif
 221
 222         /* Initialize the implementation-specific bits. */
 223
 224         threads_impl_thread_reuse(t);
 225
 226         /* Add the thread to the thread list. */
 227
 228         threadlist_add(t);
 229
 230         /* Unlock the threads-lists. */
 231
 232         threads_list_unlock();
 233
 234         return t;
 235 }
 236
 237
 238 /* threads_thread_free *********************************************************
 239
 240    Remove the thread from the threads-list and free the internal
 241    thread data structure.  The thread index is added to the
 242    thread-index free-list.
 243
 244    IN:
 245        t....thread data structure
 246
 247 *******************************************************************************/
 248
 249 void threads_thread_free(threadobject *t)
 250 {
 251         /* Lock the threads lists. */
 252
 253         threads_list_lock();
 254
 255         /* Remove the thread from the thread-list. */
 256
 257         threadlist_remove(t);
 258
 259         /* Add the thread index to the free list. */
 260
 261         threadlist_index_add(t->index);
 262
 263         /* Add the thread data structure to the free list. */
 264
 265         threads_thread_set_object(t, NULL);
 266
 267         threadlist_free_add(t);
 268
 269         /* Unlock the threads lists. */
 270
 271         threads_list_unlock();
 272 }
 273
 274
 275 /* threads_thread_start_internal ***********************************************
 276
 277    Start an internal thread in the JVM.  No Java thread objects exists
 278    so far.
 279
 280    IN:
 281       name.......UTF-8 name of the thread
 282       f..........function pointer to C function to start
 283
 284 *******************************************************************************/
 285
 286 bool threads_thread_start_internal(utf *name, functionptr f)
 287 {
 288         threadobject       *t;
 289         java_lang_Thread   *object;
 290 #if defined(WITH_CLASSPATH_GNU)
 291         java_lang_VMThread *vmt;
 292 #endif
 293
 294         /* Enter the join-mutex, so if the main-thread is currently
 295            waiting to join all threads, the number of non-daemon threads
 296            is correct. */
 297
 298         threads_mutex_join_lock();
 299
 300         /* create internal thread data-structure */
 301
 302         t = threads_thread_new();
 303
 304         t->flags |= THREAD_FLAG_INTERNAL | THREAD_FLAG_DAEMON;
 305
 306         /* The thread is flagged as (non-)daemon thread, we can leave the
 307            mutex. */
 308
 309         threads_mutex_join_unlock();
 310
 311         /* create the java thread object */
 312
 313         object = (java_lang_Thread *) builtin_new(class_java_lang_Thread);
 314
 315         /* XXX memory leak!!! */
 316         if (object == NULL)
 317                 return false;
 318
 319 #if defined(WITH_CLASSPATH_GNU)
 320         vmt = (java_lang_VMThread *) builtin_new(class_java_lang_VMThread);
 321
 322         /* XXX memory leak!!! */
 323         if (vmt == NULL)
 324                 return false;
 325
 326         LLNI_field_set_ref(vmt, thread, object);
 327         LLNI_field_set_val(vmt, vmdata, (java_lang_Object *) t);
 328
 329         LLNI_field_set_ref(object, vmThread, vmt);
 330 #elif defined(WITH_CLASSPATH_CLDC1_1)
 331         LLNI_field_set_val(object, vm_thread, (java_lang_Object *) t);
 332 #endif
 333
 334         threads_thread_set_object(t, (java_handle_t *) object);
 335
 336         /* set java.lang.Thread fields */
 337
 338 #if defined(WITH_CLASSPATH_GNU)
 339         LLNI_field_set_ref(object, name    , (java_lang_String *) javastring_new(name));
 340 #elif defined(WITH_CLASSPATH_CLDC1_1)
 341         /* FIXME: In cldc the name is a char[] */
 342 /*      LLNI_field_set_ref(object, name    , (java_chararray *) javastring_new(name)); */
 343         LLNI_field_set_ref(object, name    , NULL);
 344 #endif
 345
 346 #if defined(ENABLE_JAVASE)
 347         LLNI_field_set_val(object, daemon  , true);
 348 #endif
 349
 350         LLNI_field_set_val(object, priority, NORM_PRIORITY);
 351
 352         /* start the thread */
 353
 354         threads_impl_thread_start(t, f);
 355
 356         /* everything's ok */
 357
 358         return true;
 359 }
 360
 361
 362 /* threads_thread_start ********************************************************
 363
 364    Start a Java thread in the JVM.  Only the java thread object exists
 365    so far.
 366
 367    IN:
 368       object.....the java thread object java.lang.Thread
 369
 370 *******************************************************************************/
 371
 372 void threads_thread_start(java_handle_t *object)
 373 {
 374         java_lang_Thread   *o;
 375         threadobject       *thread;
 376 #if defined(WITH_CLASSPATH_GNU)
 377         java_lang_VMThread *vmt;
 378 #endif
 379
 380         o = (java_lang_Thread *) object;
 381
 382         /* Enter the join-mutex, so if the main-thread is currently
 383            waiting to join all threads, the number of non-daemon threads
 384            is correct. */
 385
 386         threads_mutex_join_lock();
 387
 388         /* create internal thread data-structure */
 389
 390         thread = threads_thread_new();
 391
 392         /* this is a normal Java thread */
 393
 394         thread->flags |= THREAD_FLAG_JAVA;
 395
 396 #if defined(ENABLE_JAVASE)
 397         /* is this a daemon thread? */
 398
 399         if (LLNI_field_direct(o, daemon) == true)
 400                 thread->flags |= THREAD_FLAG_DAEMON;
 401 #endif
 402
 403         /* The thread is flagged and (non-)daemon thread, we can leave the
 404            mutex. */
 405
 406         threads_mutex_join_unlock();
 407
 408         /* link the two objects together */
 409
 410         threads_thread_set_object(thread, object);
 411
 412 #if defined(WITH_CLASSPATH_GNU)
 413         LLNI_field_get_ref(o, vmThread, vmt);
 414
 415         assert(vmt);
 416         assert(LLNI_field_direct(vmt, vmdata) == NULL);
 417
 418         LLNI_field_set_val(vmt, vmdata, (java_lang_Object *) thread);
 419 #elif defined(WITH_CLASSPATH_CLDC1_1)
 420         LLNI_field_set_val(o, vm_thread, (java_lang_Object *) thread);
 421 #endif
 422
 423         /* Start the thread.  Don't pass a function pointer (NULL) since
 424            we want Thread.run()V here. */
 425
 426         threads_impl_thread_start(thread, NULL);
 427 }
 428
 429
 430 /* threads_thread_print_info ***************************************************
 431
 432    Print information of the passed thread.
 433
 434 *******************************************************************************/
 435
 436 void threads_thread_print_info(threadobject *t)
 437 {
 438         java_lang_Thread *object;
 439 #if defined(WITH_CLASSPATH_GNU)
 440         java_lang_String *namestring;
 441 #endif
 442         utf              *name;
 443
 444         assert(t->state != THREAD_STATE_NEW);
 445
 446         /* the thread may be currently in initalization, don't print it */
 447
 448         object = (java_lang_Thread *) threads_thread_get_object(t);
 449
 450         if (object != NULL) {
 451                 /* get thread name */
 452
 453 #if defined(WITH_CLASSPATH_GNU)
 454                 LLNI_field_get_ref(object, name, namestring);
 455                 name = javastring_toutf((java_handle_t *) namestring, false);
 456 #elif defined(WITH_CLASSPATH_SUN) || defined(WITH_CLASSPATH_CLDC1_1)
 457                 /* FIXME: In cldc the name is a char[] */
 458 /*              name = object->name; */
 459                 name = utf_null;
 460 #else
 461 # error unknown classpath configuration
 462 #endif
 463
 464                 printf("\"");
 465                 utf_display_printable_ascii(name);
 466                 printf("\"");
 467
 468                 if (t->flags & THREAD_FLAG_DAEMON)
 469                         printf(" daemon");
 470
 471                 printf(" prio=%d", LLNI_field_direct(object, priority));
 472
 473 #if SIZEOF_VOID_P == 8
 474                 printf(" t=0x%016lx tid=0x%016lx (%ld)",
 475                            (ptrint) t, (ptrint) t->tid, (ptrint) t->tid);
 476 #else
 477                 printf(" t=0x%08x tid=0x%08x (%d)",
 478                            (ptrint) t, (ptrint) t->tid, (ptrint) t->tid);
 479 #endif
 480
 481                 printf(" index=%d", t->index);
 482
 483                 /* print thread state */
 484
 485                 switch (t->state) {
 486                 case THREAD_STATE_NEW:
 487                         printf(" new");
 488                         break;
 489                 case THREAD_STATE_RUNNABLE:
 490                         printf(" runnable");
 491                         break;
 492                 case THREAD_STATE_BLOCKED:
 493                         printf(" blocked");
 494                         break;
 495                 case THREAD_STATE_WAITING:
 496                         printf(" waiting");
 497                         break;
 498                 case THREAD_STATE_TIMED_WAITING:
 499                         printf(" waiting on condition");
 500                         break;
 501                 case THREAD_STATE_TERMINATED:
 502                         printf(" terminated");
 503                         break;
 504                 default:
 505                         vm_abort("threads_thread_print_info: unknown thread state %d",
 506                                          t->state);
 507                 }
 508         }
 509 }
 510
 511
 512 /* threads_get_current_tid *****************************************************
 513
 514    Return the tid of the current thread.
 515
 516    RETURN VALUE:
 517        the current tid
 518
 519 *******************************************************************************/
 520
 521 ptrint threads_get_current_tid(void)
 522 {
 523         threadobject *thread;
 524
 525         thread = THREADOBJECT;
 526
 527         /* this may happen during bootstrap */
 528
 529         if (thread == NULL)
 530                 return 0;
 531
 532         return (ptrint) thread->tid;
 533 }
 534
 535
 536 /* threads_thread_state_runnable ***********************************************
 537
 538    Set the current state of the given thread to THREAD_STATE_RUNNABLE.
 539
 540    NOTE: If the thread has already terminated, don't set the state.
 541          This is important for threads_detach_thread.
 542
 543 *******************************************************************************/
 544
 545 void threads_thread_state_runnable(threadobject *t)
 546 {
 547         /* Set the state inside a lock. */
 548
 549         threads_list_lock();
 550
 551         if (t->state != THREAD_STATE_TERMINATED)
 552                 t->state = THREAD_STATE_RUNNABLE;
 553
 554         DEBUGTHREADS("is RUNNABLE", t);
 555
 556         threads_list_unlock();
 557 }
 558
 559
 560 /* threads_thread_state_waiting ************************************************
 561
 562    Set the current state of the given thread to THREAD_STATE_WAITING.
 563
 564    NOTE: If the thread has already terminated, don't set the state.
 565          This is important for threads_detach_thread.
 566
 567 *******************************************************************************/
 568
 569 void threads_thread_state_waiting(threadobject *t)
 570 {
 571         /* Set the state inside a lock. */
 572
 573         threads_list_lock();
 574
 575         if (t->state != THREAD_STATE_TERMINATED)
 576                 t->state = THREAD_STATE_WAITING;
 577
 578         DEBUGTHREADS("is WAITING", t);
 579
 580         threads_list_unlock();
 581 }
 582
 583
 584 /* threads_thread_state_timed_waiting ******************************************
 585
 586    Set the current state of the given thread to
 587    THREAD_STATE_TIMED_WAITING.
 588
 589    NOTE: If the thread has already terminated, don't set the state.
 590          This is important for threads_detach_thread.
 591
 592 *******************************************************************************/
 593
 594 void threads_thread_state_timed_waiting(threadobject *t)
 595 {
 596         /* Set the state inside a lock. */
 597
 598         threads_list_lock();
 599
 600         if (t->state != THREAD_STATE_TERMINATED)
 601                 t->state = THREAD_STATE_TIMED_WAITING;
 602
 603         DEBUGTHREADS("is TIMED_WAITING", t);
 604
 605         threads_list_unlock();
 606 }
 607
 608
 609 /* threads_thread_state_terminated *********************************************
 610
 611    Set the current state of the given thread to
 612    THREAD_STATE_TERMINATED.
 613
 614 *******************************************************************************/
 615
 616 void threads_thread_state_terminated(threadobject *t)
 617 {
 618         /* set the state in the lock */
 619
 620         threads_list_lock();
 621
 622         t->state = THREAD_STATE_TERMINATED;
 623
 624         DEBUGTHREADS("is TERMINATED", t);
 625
 626         threads_list_unlock();
 627 }
 628
 629
 630 /* threads_thread_get_state ****************************************************
 631
 632    Returns the current state of the given thread.
 633
 634 *******************************************************************************/
 635
 636 utf *threads_thread_get_state(threadobject *t)
 637 {
 638         utf *u;
 639
 640         switch (t->state) {
 641         case THREAD_STATE_NEW:
 642                 u = utf_new_char("NEW");
 643                 break;
 644         case THREAD_STATE_RUNNABLE:
 645                 u = utf_new_char("RUNNABLE");
 646                 break;
 647         case THREAD_STATE_BLOCKED:
 648                 u = utf_new_char("BLOCKED");
 649                 break;
 650         case THREAD_STATE_WAITING:
 651                 u = utf_new_char("WAITING");
 652                 break;
 653         case THREAD_STATE_TIMED_WAITING:
 654                 u = utf_new_char("TIMED_WAITING");
 655                 break;
 656         case THREAD_STATE_TERMINATED:
 657                 u = utf_new_char("TERMINATED");
 658                 break;
 659         default:
 660                 vm_abort("threads_get_state: unknown thread state %d", t->state);
 661
 662                 /* keep compiler happy */
 663
 664                 u = NULL;
 665         }
 666
 667         return u;
 668 }
 669
 670
 671 /* threads_thread_is_alive *****************************************************
 672
 673    Returns if the give thread is alive.
 674
 675 *******************************************************************************/
 676
 677 bool threads_thread_is_alive(threadobject *t)
 678 {
 679         switch (t->state) {
 680         case THREAD_STATE_NEW:
 681         case THREAD_STATE_TERMINATED:
 682                 return false;
 683
 684         case THREAD_STATE_RUNNABLE:
 685         case THREAD_STATE_BLOCKED:
 686         case THREAD_STATE_WAITING:
 687         case THREAD_STATE_TIMED_WAITING:
 688                 return true;
 689
 690         default:
 691                 vm_abort("threads_thread_is_alive: unknown thread state %d", t->state);
 692         }
 693
 694         /* keep compiler happy */
 695
 696         return false;
 697 }
 698
 699
 700 /* threads_dump ****************************************************************
 701
 702    Dumps info for all threads running in the JVM.  This function is
 703    called when SIGQUIT (<ctrl>-\) is sent to CACAO.
 704
 705 *******************************************************************************/
 706
 707 void threads_dump(void)
 708 {
 709         threadobject *t;
 710
 711         /* XXX we should stop the world here */
 712
 713         /* lock the threads lists */
 714
 715         threads_list_lock();
 716
 717         printf("Full thread dump CACAO "VERSION":\n");
 718
 719         /* iterate over all started threads */
 720
 721         for (t = threadlist_first(); t != NULL; t = threadlist_next(t)) {
 722                 /* ignore threads which are in state NEW */
 723                 if (t->state == THREAD_STATE_NEW)
 724                         continue;
 725
 726 #if defined(ENABLE_GC_CACAO)
 727                 /* Suspend the thread. */
 728                 /* XXX Is the suspend reason correct? */
 729
 730                 if (threads_suspend_thread(t, SUSPEND_REASON_JNI) == false)
 731                         vm_abort("threads_dump: threads_suspend_thread failed");
 732 #endif
 733
 734                 /* Print thread info. */
 735
 736                 printf("\n");
 737                 threads_thread_print_info(t);
 738                 printf("\n");
 739
 740                 /* Print trace of thread. */
 741
 742                 threads_thread_print_stacktrace(t);
 743
 744 #if defined(ENABLE_GC_CACAO)
 745                 /* Resume the thread. */
 746
 747                 if (threads_resume_thread(t) == false)
 748                         vm_abort("threads_dump: threads_resume_thread failed");
 749 #endif
 750         }
 751
 752         /* unlock the threads lists */
 753
 754         threads_list_unlock();
 755 }
 756
 757
 758 /* threads_thread_print_stacktrace *********************************************
 759
 760    Print the current stacktrace of the given thread.
 761
 762 *******************************************************************************/
 763
 764 void threads_thread_print_stacktrace(threadobject *thread)
 765 {
 766         stackframeinfo_t        *sfi;
 767         java_handle_bytearray_t *ba;
 768         stacktrace_t            *st;
 769
 770         /* Build a stacktrace for the passed thread. */
 771
 772         sfi = thread->_stackframeinfo;
 773         ba  = stacktrace_get(sfi);
 774
 775         if (ba != NULL) {
 776                 /* We need a critical section here as we use the byte-array
 777                    data pointer directly. */
 778
 779                 LLNI_CRITICAL_START;
 780
 781                 st = (stacktrace_t *) LLNI_array_data(ba);
 782
 783                 /* Print stacktrace. */
 784
 785                 stacktrace_print(st);
 786
 787                 LLNI_CRITICAL_END;
 788         }
 789         else {
 790                 puts("\t<<No stacktrace available>>");
 791                 fflush(stdout);
 792         }
 793 }
 794
 795
 796 /* threads_print_stacktrace ****************************************************
 797
 798    Print the current stacktrace of the current thread.
 799
 800 *******************************************************************************/
 801
 802 void threads_print_stacktrace(void)
 803 {
 804         threadobject *thread;
 805
 806         thread = THREADOBJECT;
 807
 808         threads_thread_print_stacktrace(thread);
 809 }
 810
 811
 812 /*
 813  * These are local overrides for various environment variables in Emacs.
 814  * Please do not remove this and leave it at the end of the file, where
 815  * Emacs will automagically detect them.
 816  * ---------------------------------------------------------------------
 817  * Local variables:
 818  * mode: c
 819  * indent-tabs-mode: t
 820  * c-basic-offset: 4
 821  * tab-width: 4
 822  * End:
 823  * vim:noexpandtab:sw=4:ts=4:
 824  */