ext/threads/threads.xs

   1 #define PERL_NO_GET_CONTEXT
   2 #include "EXTERN.h"
   3 #include "perl.h"
   4 #include "XSUB.h"
   5
   6 #ifdef USE_ITHREADS
   7
   8
   9 #ifdef WIN32
  10 #include <windows.h>
  11 #include <win32thread.h>
  12 #else
  13 #ifdef OS2
  14 typedef perl_os_thread pthread_t;
  15 #else
  16 #include <pthread.h>
  17 #endif
  18 #include <thread.h>
  19 #define PERL_THREAD_SETSPECIFIC(k,v) pthread_setspecific(k,v)
  20 #ifdef OLD_PTHREADS_API
  21 #define PERL_THREAD_DETACH(t) pthread_detach(&(t))
  22 #else
  23 #define PERL_THREAD_DETACH(t) pthread_detach((t))
  24 #endif  /* OLD_PTHREADS_API */
  25 #endif
  26
  27
  28
  29
  30 /* Values for 'state' member */
  31 #define PERL_ITHR_JOINABLE              0
  32 #define PERL_ITHR_DETACHED              1
  33 #define PERL_ITHR_FINISHED              4
  34 #define PERL_ITHR_JOINED                2
  35
  36 typedef struct ithread_s {
  37     struct ithread_s *next;     /* Next thread in the list */
  38     struct ithread_s *prev;     /* Prev thread in the list */
  39     PerlInterpreter *interp;    /* The threads interpreter */
  40     I32 tid;                    /* Threads module's thread id */
  41     perl_mutex mutex;           /* Mutex for updating things in this struct */
  42     I32 count;                  /* How many SVs have a reference to us */
  43     signed char state;          /* Are we detached ? */
  44     int gimme;                  /* Context of create */
  45     SV* init_function;          /* Code to run */
  46     SV* params;                 /* Args to pass function */
  47 #ifdef WIN32
  48         DWORD   thr;            /* OS's idea if thread id */
  49         HANDLE handle;          /* OS's waitable handle */
  50 #else
  51         pthread_t thr;          /* OS's handle for the thread */
  52 #endif
  53 } ithread;
  54
  55 ithread *threads;
  56
  57 /* Macros to supply the aTHX_ in an embed.h like manner */
  58 #define ithread_join(thread)            Perl_ithread_join(aTHX_ thread)
  59 #define ithread_DESTROY(thread)         Perl_ithread_DESTROY(aTHX_ thread)
  60 #define ithread_CLONE(thread)           Perl_ithread_CLONE(aTHX_ thread)
  61 #define ithread_detach(thread)          Perl_ithread_detach(aTHX_ thread)
  62 #define ithread_tid(thread)             ((thread)->tid)
  63 #define ithread_yield(thread)           (YIELD);
  64
  65 static perl_mutex create_destruct_mutex;  /* protects the creation and destruction of threads*/
  66
  67 I32 tid_counter = 0;
  68 I32 known_threads = 0;
  69 I32 active_threads = 0;
  70
  71
  72 void Perl_ithread_set (pTHX_ ithread* thread)
  73 {
  74   SV* thread_sv = newSViv(PTR2IV(thread));
  75   if(!hv_store(PL_modglobal, "threads::self", 12, thread_sv,0)) {
  76     croak("%s\n","Internal error, couldn't set TLS");
  77   }
  78 }
  79
  80 ithread* Perl_ithread_get (pTHX) {
  81   SV** thread_sv = hv_fetch(PL_modglobal, "threads::self",12,0);
  82   if(!thread_sv) {
  83     croak("%s\n","Internal error, couldn't get TLS");
  84   }
  85   return INT2PTR(ithread*,SvIV(*thread_sv));
  86 }
  87
  88
  89
  90 /*
  91  *  Clear up after thread is done with
  92  */
  93 void
  94 Perl_ithread_destruct (pTHX_ ithread* thread, const char *why)
  95 {
  96         MUTEX_LOCK(&thread->mutex);
  97         if (!thread->next) {
  98             Perl_croak(aTHX_ "panic: destruct destroyed thread %p (%s)",thread, why);
  99         }
 100         if (thread->count != 0) {
 101                 MUTEX_UNLOCK(&thread->mutex);
 102                 return;
 103         }
 104         MUTEX_LOCK(&create_destruct_mutex);
 105         /* Remove from circular list of threads */
 106         if (thread->next == thread) {
 107             /* last one should never get here ? */
 108             threads = NULL;
 109         }
 110         else {
 111             thread->next->prev = thread->prev;
 112             thread->prev->next = thread->next;
 113             if (threads == thread) {
 114                 threads = thread->next;
 115             }
 116             thread->next = NULL;
 117             thread->prev = NULL;
 118         }
 119         known_threads--;
 120         assert( known_threads >= 0 );
 121 #if 0
 122         Perl_warn(aTHX_ "destruct %d @ %p by %p now %d",
 123                   thread->tid,thread->interp,aTHX, known_threads);
 124 #endif
 125         MUTEX_UNLOCK(&create_destruct_mutex);
 126         /* Thread is now disowned */
 127
 128         if(thread->interp) {
 129             dTHXa(thread->interp);
 130             ithread*        current_thread;
 131 #ifdef OEMVS
 132             void *ptr;
 133 #endif
 134             PERL_SET_CONTEXT(thread->interp);
 135             current_thread = Perl_ithread_get(aTHX);
 136             Perl_ithread_set(aTHX_ thread);
 137
 138
 139
 140
 141             SvREFCNT_dec(thread->params);
 142
 143
 144
 145             thread->params = Nullsv;
 146             perl_destruct(thread->interp);
 147             perl_free(thread->interp);
 148             thread->interp = NULL;
 149         }
 150         MUTEX_UNLOCK(&thread->mutex);
 151         MUTEX_DESTROY(&thread->mutex);
 152         PerlMemShared_free(thread);
 153
 154         PERL_SET_CONTEXT(aTHX);
 155 }
 156
 157 int
 158 Perl_ithread_hook(pTHX)
 159 {
 160     int veto_cleanup = 0;
 161     MUTEX_LOCK(&create_destruct_mutex);
 162     if (aTHX == PL_curinterp && active_threads != 1) {
 163         Perl_warn(aTHX_ "A thread exited while %" IVdf " threads were running",
 164                                                 (IV)active_threads);
 165         veto_cleanup = 1;
 166     }
 167     MUTEX_UNLOCK(&create_destruct_mutex);
 168     return veto_cleanup;
 169 }
 170
 171 void
 172 Perl_ithread_detach(pTHX_ ithread *thread)
 173 {
 174     MUTEX_LOCK(&thread->mutex);
 175     if (!(thread->state & (PERL_ITHR_DETACHED|PERL_ITHR_JOINED))) {
 176         thread->state |= PERL_ITHR_DETACHED;
 177 #ifdef WIN32
 178         CloseHandle(thread->handle);
 179         thread->handle = 0;
 180 #else
 181         PERL_THREAD_DETACH(thread->thr);
 182 #endif
 183     }
 184     if ((thread->state & PERL_ITHR_FINISHED) &&
 185         (thread->state & PERL_ITHR_DETACHED)) {
 186         MUTEX_UNLOCK(&thread->mutex);
 187         Perl_ithread_destruct(aTHX_ thread, "detach");
 188     }
 189     else {
 190         MUTEX_UNLOCK(&thread->mutex);
 191     }
 192 }
 193
 194 /* MAGIC (in mg.h sense) hooks */
 195
 196 int
 197 ithread_mg_get(pTHX_ SV *sv, MAGIC *mg)
 198 {
 199     ithread *thread = (ithread *) mg->mg_ptr;
 200     SvIVX(sv) = PTR2IV(thread);
 201     SvIOK_on(sv);
 202     return 0;
 203 }
 204
 205 int
 206 ithread_mg_free(pTHX_ SV *sv, MAGIC *mg)
 207 {
 208     ithread *thread = (ithread *) mg->mg_ptr;
 209     MUTEX_LOCK(&thread->mutex);
 210     thread->count--;
 211     if (thread->count == 0) {
 212        if(thread->state & PERL_ITHR_FINISHED &&
 213           (thread->state & PERL_ITHR_DETACHED ||
 214            thread->state & PERL_ITHR_JOINED))
 215        {
 216             MUTEX_UNLOCK(&thread->mutex);
 217             Perl_ithread_destruct(aTHX_ thread, "no reference");
 218        }
 219        else {
 220             MUTEX_UNLOCK(&thread->mutex);
 221        }
 222     }
 223     else {
 224         MUTEX_UNLOCK(&thread->mutex);
 225     }
 226     return 0;
 227 }
 228
 229 int
 230 ithread_mg_dup(pTHX_ MAGIC *mg, CLONE_PARAMS *param)
 231 {
 232     ithread *thread = (ithread *) mg->mg_ptr;
 233     MUTEX_LOCK(&thread->mutex);
 234     thread->count++;
 235     MUTEX_UNLOCK(&thread->mutex);
 236     return 0;
 237 }
 238
 239 MGVTBL ithread_vtbl = {
 240  ithread_mg_get,        /* get */
 241  0,                     /* set */
 242  0,                     /* len */
 243  0,                     /* clear */
 244  ithread_mg_free,       /* free */
 245  0,                     /* copy */
 246  ithread_mg_dup         /* dup */
 247 };
 248
 249
 250 /*
 251  *      Starts executing the thread. Needs to clean up memory a tad better.
 252  *      Passed as the C level function to run in the new thread
 253  */
 254
 255 #ifdef WIN32
 256 THREAD_RET_TYPE
 257 Perl_ithread_run(LPVOID arg) {
 258 #else
 259 void*
 260 Perl_ithread_run(void * arg) {
 261 #endif
 262         ithread* thread = (ithread*) arg;
 263         dTHXa(thread->interp);
 264         PERL_SET_CONTEXT(thread->interp);
 265         Perl_ithread_set(aTHX_ thread);
 266
 267 #if 0
 268         /* Far from clear messing with ->thr child-side is a good idea */
 269         MUTEX_LOCK(&thread->mutex);
 270 #ifdef WIN32
 271         thread->thr = GetCurrentThreadId();
 272 #else
 273         thread->thr = pthread_self();
 274 #endif
 275         MUTEX_UNLOCK(&thread->mutex);
 276 #endif
 277
 278         PL_perl_destruct_level = 2;
 279
 280         {
 281                 AV* params = (AV*) SvRV(thread->params);
 282                 I32 len = av_len(params)+1;
 283                 int i;
 284                 dSP;
 285                 ENTER;
 286                 SAVETMPS;
 287                 PUSHMARK(SP);
 288                 for(i = 0; i < len; i++) {
 289                     XPUSHs(av_shift(params));
 290                 }
 291                 PUTBACK;
 292                 len = call_sv(thread->init_function, thread->gimme|G_EVAL);
 293
 294                 SPAGAIN;
 295                 for (i=len-1; i >= 0; i--) {
 296                   SV *sv = POPs;
 297                   av_store(params, i, SvREFCNT_inc(sv));
 298                 }
 299                 if (SvTRUE(ERRSV)) {
 300                     Perl_warn(aTHX_ "thread failed to start: %" SVf, ERRSV);
 301                 }
 302                 FREETMPS;
 303                 LEAVE;
 304                 SvREFCNT_dec(thread->init_function);
 305         }
 306
 307         PerlIO_flush((PerlIO*)NULL);
 308         MUTEX_LOCK(&thread->mutex);
 309         thread->state |= PERL_ITHR_FINISHED;
 310
 311         if (thread->state & PERL_ITHR_DETACHED) {
 312                 MUTEX_UNLOCK(&thread->mutex);
 313                 Perl_ithread_destruct(aTHX_ thread, "detached finish");
 314         } else {
 315                 MUTEX_UNLOCK(&thread->mutex);
 316         }
 317         MUTEX_LOCK(&create_destruct_mutex);
 318         active_threads--;
 319         assert( active_threads >= 0 );
 320         MUTEX_UNLOCK(&create_destruct_mutex);
 321
 322 #ifdef WIN32
 323         return (DWORD)0;
 324 #else
 325         return 0;
 326 #endif
 327 }
 328
 329 SV *
 330 ithread_to_SV(pTHX_ SV *obj, ithread *thread, char *classname, bool inc)
 331 {
 332     SV *sv;
 333     MAGIC *mg;
 334     if (inc) {
 335         MUTEX_LOCK(&thread->mutex);
 336         thread->count++;
 337         MUTEX_UNLOCK(&thread->mutex);
 338     }
 339     if (!obj)
 340      obj = newSV(0);
 341     sv = newSVrv(obj,classname);
 342     sv_setiv(sv,PTR2IV(thread));
 343     mg = sv_magicext(sv,Nullsv,PERL_MAGIC_shared_scalar,&ithread_vtbl,(char *)thread,0);
 344     mg->mg_flags |= MGf_DUP;
 345     SvREADONLY_on(sv);
 346     return obj;
 347 }
 348
 349 ithread *
 350 SV_to_ithread(pTHX_ SV *sv)
 351 {
 352     if (SvROK(sv))
 353      {
 354       return INT2PTR(ithread*, SvIV(SvRV(sv)));
 355      }
 356     else
 357      {
 358       return Perl_ithread_get(aTHX);
 359      }
 360 }
 361
 362 /*
 363  * ithread->create(); ( aka ithread->new() )
 364  * Called in context of parent thread
 365  */
 366
 367 SV *
 368 Perl_ithread_create(pTHX_ SV *obj, char* classname, SV* init_function, SV* params)
 369 {
 370         ithread*        thread;
 371         CLONE_PARAMS    clone_param;
 372         ithread*        current_thread = Perl_ithread_get(aTHX);
 373
 374         SV**            tmps_tmp = PL_tmps_stack;
 375         I32             tmps_ix  = PL_tmps_ix;
 376
 377
 378         MUTEX_LOCK(&create_destruct_mutex);
 379         thread = PerlMemShared_malloc(sizeof(ithread));
 380         Zero(thread,1,ithread);
 381         thread->next = threads;
 382         thread->prev = threads->prev;
 383         threads->prev = thread;
 384         thread->prev->next = thread;
 385         /* Set count to 1 immediately in case thread exits before
 386          * we return to caller !
 387          */
 388         thread->count = 1;
 389         MUTEX_INIT(&thread->mutex);
 390         thread->tid = tid_counter++;
 391         thread->gimme = GIMME_V;
 392
 393         /* "Clone" our interpreter into the thread's interpreter
 394          * This gives thread access to "static data" and code.
 395          */
 396
 397         PerlIO_flush((PerlIO*)NULL);
 398         Perl_ithread_set(aTHX_ thread);
 399
 400         SAVEBOOL(PL_srand_called); /* Save this so it becomes the correct
 401                                       value */
 402         PL_srand_called = FALSE; /* Set it to false so we can detect
 403                                     if it gets set during the clone */
 404
 405 #ifdef WIN32
 406         thread->interp = perl_clone(aTHX, CLONEf_KEEP_PTR_TABLE | CLONEf_CLONE_HOST);
 407 #else
 408         thread->interp = perl_clone(aTHX, CLONEf_KEEP_PTR_TABLE);
 409 #endif
 410         /* perl_clone leaves us in new interpreter's context.
 411            As it is tricky to spot an implicit aTHX, create a new scope
 412            with aTHX matching the context for the duration of
 413            our work for new interpreter.
 414          */
 415         {
 416             dTHXa(thread->interp);
 417
 418             /* Here we remove END blocks since they should only run
 419                in the thread they are created
 420             */
 421             SvREFCNT_dec(PL_endav);
 422             PL_endav = newAV();
 423             clone_param.flags = 0;
 424             thread->init_function = sv_dup(init_function, &clone_param);
 425             if (SvREFCNT(thread->init_function) == 0) {
 426                 SvREFCNT_inc(thread->init_function);
 427             }
 428
 429
 430
 431             thread->params = sv_dup(params, &clone_param);
 432             SvREFCNT_inc(thread->params);
 433
 434
 435             /* The code below checks that anything living on
 436                the tmps stack and has been cloned (so it lives in the
 437                ptr_table) has a refcount higher than 0
 438
 439                If the refcount is 0 it means that a something on the
 440                stack/context was holding a reference to it and
 441                since we init_stacks() in perl_clone that won't get
 442                cleaned and we will get a leaked scalar.
 443                The reason it was cloned was that it lived on the
 444                @_ stack.
 445
 446                Example of this can be found in bugreport 15837
 447                where calls in the parameter list end up as a temp
 448
 449                One could argue that this fix should be in perl_clone
 450             */
 451
 452
 453             while (tmps_ix > 0) {
 454               SV* sv = (SV*)ptr_table_fetch(PL_ptr_table, tmps_tmp[tmps_ix]);
 455               tmps_ix--;
 456               if (sv && SvREFCNT(sv) == 0) {
 457                 SvREFCNT_inc(sv);
 458                 SvREFCNT_dec(sv);
 459               }
 460             }
 461
 462
 463
 464             SvTEMP_off(thread->init_function);
 465             ptr_table_free(PL_ptr_table);
 466             PL_ptr_table = NULL;
 467             PL_exit_flags |= PERL_EXIT_DESTRUCT_END;
 468         }
 469         Perl_ithread_set(aTHX_ current_thread);
 470         PERL_SET_CONTEXT(aTHX);
 471
 472         /* Start the thread */
 473
 474 #ifdef WIN32
 475
 476         thread->handle = CreateThread(NULL, 0, Perl_ithread_run,
 477                         (LPVOID)thread, 0, &thread->thr);
 478
 479 #else
 480         {
 481           static pthread_attr_t attr;
 482           static int attr_inited = 0;
 483           static int attr_joinable = PTHREAD_CREATE_JOINABLE;
 484           if (!attr_inited) {
 485             attr_inited = 1;
 486             pthread_attr_init(&attr);
 487           }
 488 #  ifdef PTHREAD_ATTR_SETDETACHSTATE
 489             PTHREAD_ATTR_SETDETACHSTATE(&attr, attr_joinable);
 490 #  endif
 491 #  ifdef THREAD_CREATE_NEEDS_STACK
 492             if(pthread_attr_setstacksize(&attr, THREAD_CREATE_NEEDS_STACK))
 493               Perl_croak(aTHX_ "panic: pthread_attr_setstacksize failed");
 494 #  endif
 495
 496 #ifdef OLD_PTHREADS_API
 497           pthread_create( &thread->thr, attr, Perl_ithread_run, (void *)thread);
 498 #else
 499 #  if defined(HAS_PTHREAD_ATTR_SETSCOPE) && defined(PTHREAD_SCOPE_SYSTEM)
 500           pthread_attr_setscope( &attr, PTHREAD_SCOPE_SYSTEM );
 501 #  endif
 502           pthread_create( &thread->thr, &attr, Perl_ithread_run, (void *)thread);
 503 #endif
 504         }
 505 #endif
 506         known_threads++;
 507         active_threads++;
 508         MUTEX_UNLOCK(&create_destruct_mutex);
 509         sv_2mortal(params);
 510
 511         return ithread_to_SV(aTHX_ obj, thread, classname, FALSE);
 512 }
 513
 514 SV*
 515 Perl_ithread_self (pTHX_ SV *obj, char* Class)
 516 {
 517    ithread *thread = Perl_ithread_get(aTHX);
 518    if (thread)
 519         return ithread_to_SV(aTHX_ obj, thread, Class, TRUE);
 520    else
 521         Perl_croak(aTHX_ "panic: cannot find thread data");
 522    return NULL; /* silence compiler warning */
 523 }
 524
 525 /*
 526  * Joins the thread this code needs to take the returnvalue from the
 527  * call_sv and send it back
 528  */
 529
 530 void
 531 Perl_ithread_CLONE(pTHX_ SV *obj)
 532 {
 533  if (SvROK(obj))
 534   {
 535    ithread *thread = SV_to_ithread(aTHX_ obj);
 536   }
 537  else
 538   {
 539    Perl_warn(aTHX_ "CLONE %" SVf,obj);
 540   }
 541 }
 542
 543 AV*
 544 Perl_ithread_join(pTHX_ SV *obj)
 545 {
 546     ithread *thread = SV_to_ithread(aTHX_ obj);
 547     MUTEX_LOCK(&thread->mutex);
 548     if (thread->state & PERL_ITHR_DETACHED) {
 549         MUTEX_UNLOCK(&thread->mutex);
 550         Perl_croak(aTHX_ "Cannot join a detached thread");
 551     }
 552     else if (thread->state & PERL_ITHR_JOINED) {
 553         MUTEX_UNLOCK(&thread->mutex);
 554         Perl_croak(aTHX_ "Thread already joined");
 555     }
 556     else {
 557         AV* retparam;
 558 #ifdef WIN32
 559         DWORD waitcode;
 560 #else
 561         void *retval;
 562 #endif
 563         MUTEX_UNLOCK(&thread->mutex);
 564 #ifdef WIN32
 565         waitcode = WaitForSingleObject(thread->handle, INFINITE);
 566 #else
 567         pthread_join(thread->thr,&retval);
 568 #endif
 569         MUTEX_LOCK(&thread->mutex);
 570
 571         /* sv_dup over the args */
 572         {
 573           ithread*        current_thread;
 574           AV* params = (AV*) SvRV(thread->params);
 575           CLONE_PARAMS clone_params;
 576           clone_params.stashes = newAV();
 577           clone_params.flags |= CLONEf_JOIN_IN;
 578           PL_ptr_table = ptr_table_new();
 579           current_thread = Perl_ithread_get(aTHX);
 580           Perl_ithread_set(aTHX_ thread);
 581
 582 #if 0
 583           {
 584             I32 len = av_len(params)+1;
 585             I32 i;
 586             for(i = 0; i < len; i++) {
 587               sv_dump(SvRV(AvARRAY(params)[i]));
 588             }
 589           }
 590 #endif
 591           retparam = (AV*) sv_dup((SV*)params, &clone_params);
 592 #if 0
 593           {
 594             I32 len = av_len(retparam)+1;
 595             I32 i;
 596             for(i = 0; i < len; i++) {
 597                 sv_dump(SvRV(AvARRAY(retparam)[i]));
 598             }
 599           }
 600 #endif
 601           Perl_ithread_set(aTHX_ current_thread);
 602           SvREFCNT_dec(clone_params.stashes);
 603           SvREFCNT_inc(retparam);
 604           ptr_table_free(PL_ptr_table);
 605           PL_ptr_table = NULL;
 606
 607         }
 608         /* We are finished with it */
 609         thread->state |= PERL_ITHR_JOINED;
 610         MUTEX_UNLOCK(&thread->mutex);
 611
 612         return retparam;
 613     }
 614     return (AV*)NULL;
 615 }
 616
 617 void
 618 Perl_ithread_DESTROY(pTHX_ SV *sv)
 619 {
 620     ithread *thread = SV_to_ithread(aTHX_ sv);
 621     sv_unmagic(SvRV(sv),PERL_MAGIC_shared_scalar);
 622 }
 623
 624 #endif /* USE_ITHREADS */
 625
 626 MODULE = threads                PACKAGE = threads       PREFIX = ithread_
 627 PROTOTYPES: DISABLE
 628
 629 #ifdef USE_ITHREADS
 630
 631 void
 632 ithread_new (classname, function_to_call, ...)
 633 char *  classname
 634 SV *    function_to_call
 635 CODE:
 636 {
 637     AV* params = newAV();
 638     if (items > 2) {
 639         int i;
 640         for(i = 2; i < items ; i++) {
 641             av_push(params, SvREFCNT_inc(ST(i)));
 642         }
 643     }
 644     ST(0) = sv_2mortal(Perl_ithread_create(aTHX_ Nullsv, classname, function_to_call, newRV_noinc((SV*) params)));
 645     XSRETURN(1);
 646 }
 647
 648 void
 649 ithread_list(char *classname)
 650 PPCODE:
 651 {
 652   ithread *curr_thread;
 653   MUTEX_LOCK(&create_destruct_mutex);
 654   curr_thread = threads;
 655   if(curr_thread->tid != 0)
 656     XPUSHs( sv_2mortal(ithread_to_SV(aTHX_ NULL, curr_thread, classname, TRUE)));
 657   while(curr_thread) {
 658     curr_thread = curr_thread->next;
 659     if(curr_thread == threads)
 660       break;
 661     if(curr_thread->state & PERL_ITHR_DETACHED ||
 662        curr_thread->state & PERL_ITHR_JOINED)
 663          continue;
 664      XPUSHs( sv_2mortal(ithread_to_SV(aTHX_ NULL, curr_thread, classname, TRUE)));
 665   }
 666   MUTEX_UNLOCK(&create_destruct_mutex);
 667 }
 668
 669
 670 void
 671 ithread_self(char *classname)
 672 CODE:
 673 {
 674         ST(0) = sv_2mortal(Perl_ithread_self(aTHX_ Nullsv,classname));
 675         XSRETURN(1);
 676 }
 677
 678 int
 679 ithread_tid(ithread *thread)
 680
 681 void
 682 ithread_join(SV *obj)
 683 PPCODE:
 684 {
 685   AV* params = Perl_ithread_join(aTHX_ obj);
 686   int i;
 687   I32 len = AvFILL(params);
 688   for (i = 0; i <= len; i++) {
 689     SV* tmp = av_shift(params);
 690     XPUSHs(tmp);
 691     sv_2mortal(tmp);
 692   }
 693   SvREFCNT_dec(params);
 694 }
 695
 696 void
 697 yield(...)
 698 CODE:
 699 {
 700     YIELD;
 701 }
 702
 703
 704 void
 705 ithread_detach(ithread *thread)
 706
 707 void
 708 ithread_DESTROY(SV *thread)
 709
 710 #endif /* USE_ITHREADS */
 711
 712 BOOT:
 713 {
 714 #ifdef USE_ITHREADS
 715         ithread* thread;
 716         PL_perl_destruct_level = 2;
 717         MUTEX_INIT(&create_destruct_mutex);
 718         MUTEX_LOCK(&create_destruct_mutex);
 719         PL_threadhook = &Perl_ithread_hook;
 720         thread  = PerlMemShared_malloc(sizeof(ithread));
 721         Zero(thread,1,ithread);
 722         PL_perl_destruct_level = 2;
 723         MUTEX_INIT(&thread->mutex);
 724         threads = thread;
 725         thread->next = thread;
 726         thread->prev = thread;
 727         thread->interp = aTHX;
 728         thread->count  = 1;  /* Immortal. */
 729         thread->tid = tid_counter++;
 730         known_threads++;
 731         active_threads++;
 732         thread->state = PERL_ITHR_DETACHED;
 733 #ifdef WIN32
 734         thread->thr = GetCurrentThreadId();
 735 #else
 736         thread->thr = pthread_self();
 737 #endif
 738
 739         Perl_ithread_set(aTHX_ thread);
 740         MUTEX_UNLOCK(&create_destruct_mutex);
 741 #endif /* USE_ITHREADS */
 742 }
 743