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 #ifdef WIN32
   9 #include <windows.h>
  10 #include <win32thread.h>
  11 #define PERL_THREAD_SETSPECIFIC(k,v) TlsSetValue(k,v)
  12 #define PERL_THREAD_GETSPECIFIC(k,v) v = TlsGetValue(k)
  13 #define PERL_THREAD_ALLOC_SPECIFIC(k) \
  14 STMT_START {\
  15   if((k = TlsAlloc()) == TLS_OUT_OF_INDEXES) {\
  16     PerlIO_printf(PerlIO_stderr(), "panic threads.xs: TlsAlloc");\
  17     exit(1);\
  18   }\
  19 } STMT_END
  20 #else
  21 #ifdef OS2
  22 typedef perl_os_thread pthread_t;
  23 #else
  24 #include <pthread.h>
  25 #endif
  26 #include <thread.h>
  27
  28 #define PERL_THREAD_SETSPECIFIC(k,v) pthread_setspecific(k,v)
  29 #ifdef OLD_PTHREADS_API
  30 #define PERL_THREAD_DETACH(t) pthread_detach(&(t))
  31 #define PERL_THREAD_GETSPECIFIC(k,v) pthread_getspecific(k,&v)
  32 #define PERL_THREAD_ALLOC_SPECIFIC(k) STMT_START {\
  33   if(pthread_keycreate(&(k),0)) {\
  34     PerlIO_printf(PerlIO_stderr(), "panic threads.xs: pthread_key_create");\
  35     exit(1);\
  36   }\
  37 } STMT_END
  38 #else
  39 #define PERL_THREAD_DETACH(t) pthread_detach((t))
  40 #define PERL_THREAD_GETSPECIFIC(k,v) v = pthread_getspecific(k)
  41 #define PERL_THREAD_ALLOC_SPECIFIC(k) STMT_START {\
  42   if(pthread_key_create(&(k),0)) {\
  43     PerlIO_printf(PerlIO_stderr(), "panic threads.xs: pthread_key_create");\
  44     exit(1);\
  45   }\
  46 } STMT_END
  47 #endif
  48 #endif
  49
  50 /* Values for 'state' member */
  51 #define PERL_ITHR_JOINABLE              0
  52 #define PERL_ITHR_DETACHED              1
  53 #define PERL_ITHR_FINISHED              4
  54 #define PERL_ITHR_JOINED                2
  55
  56 typedef struct ithread_s {
  57     struct ithread_s *next;     /* Next thread in the list */
  58     struct ithread_s *prev;     /* Prev thread in the list */
  59     PerlInterpreter *interp;    /* The threads interpreter */
  60     I32 tid;                    /* Threads module's thread id */
  61     perl_mutex mutex;           /* Mutex for updating things in this struct */
  62     I32 count;                  /* How many SVs have a reference to us */
  63     signed char state;          /* Are we detached ? */
  64     int gimme;                  /* Context of create */
  65     SV* init_function;          /* Code to run */
  66     SV* params;                 /* Args to pass function */
  67 #ifdef WIN32
  68         DWORD   thr;            /* OS's idea if thread id */
  69         HANDLE handle;          /* OS's waitable handle */
  70 #else
  71         pthread_t thr;          /* OS's handle for the thread */
  72 #endif
  73 } ithread;
  74
  75 ithread *threads;
  76
  77 /* Macros to supply the aTHX_ in an embed.h like manner */
  78 #define ithread_join(thread)            Perl_ithread_join(aTHX_ thread)
  79 #define ithread_DESTROY(thread)         Perl_ithread_DESTROY(aTHX_ thread)
  80 #define ithread_CLONE(thread)           Perl_ithread_CLONE(aTHX_ thread)
  81 #define ithread_detach(thread)          Perl_ithread_detach(aTHX_ thread)
  82 #define ithread_tid(thread)             ((thread)->tid)
  83 #define ithread_yield(thread)           (YIELD);
  84
  85 static perl_mutex create_destruct_mutex;  /* protects the creation and destruction of threads*/
  86
  87 I32 tid_counter = 0;
  88 I32 known_threads = 0;
  89 I32 active_threads = 0;
  90 perl_key self_key;
  91
  92 /*
  93  *  Clear up after thread is done with
  94  */
  95 void
  96 Perl_ithread_destruct (pTHX_ ithread* thread, const char *why)
  97 {
  98         MUTEX_LOCK(&thread->mutex);
  99         if (!thread->next) {
 100             Perl_croak(aTHX_ "panic: destruct destroyed thread %p (%s)",thread, why);
 101         }
 102         if (thread->count != 0) {
 103                 MUTEX_UNLOCK(&thread->mutex);
 104                 return;
 105         }
 106         MUTEX_LOCK(&create_destruct_mutex);
 107         /* Remove from circular list of threads */
 108         if (thread->next == thread) {
 109             /* last one should never get here ? */
 110             threads = NULL;
 111         }
 112         else {
 113             thread->next->prev = thread->prev;
 114             thread->prev->next = thread->next;
 115             if (threads == thread) {
 116                 threads = thread->next;
 117             }
 118             thread->next = NULL;
 119             thread->prev = NULL;
 120         }
 121         known_threads--;
 122         assert( known_threads >= 0 );
 123 #if 0
 124         Perl_warn(aTHX_ "destruct %d @ %p by %p now %d",
 125                   thread->tid,thread->interp,aTHX, known_threads);
 126 #endif
 127         MUTEX_UNLOCK(&create_destruct_mutex);
 128         /* Thread is now disowned */
 129
 130         if(thread->interp) {
 131             dTHXa(thread->interp);
 132             ithread*        current_thread;
 133             PERL_SET_CONTEXT(thread->interp);
 134             PERL_THREAD_GETSPECIFIC(self_key,current_thread);
 135             PERL_THREAD_SETSPECIFIC(self_key,thread);
 136
 137
 138
 139             SvREFCNT_dec(thread->params);
 140
 141
 142
 143             thread->params = Nullsv;
 144             perl_destruct(thread->interp);
 145             perl_free(thread->interp);
 146             thread->interp = NULL;
 147             PERL_THREAD_SETSPECIFIC(self_key,current_thread);
 148
 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_THREAD_SETSPECIFIC(self_key,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     ithread *thread;
 353 #ifdef OEMVS
 354     void *ptr;
 355 #endif
 356     if (SvROK(sv))
 357      {
 358       thread = INT2PTR(ithread*, SvIV(SvRV(sv)));
 359      }
 360     else
 361      {
 362 #ifdef OEMVS
 363       PERL_THREAD_GETSPECIFIC(self_key,ptr);
 364       thread = (ithread *) ptr;
 365 #else
 366       PERL_THREAD_GETSPECIFIC(self_key,thread);
 367 #endif
 368      }
 369     return thread;
 370 }
 371
 372 /*
 373  * ithread->create(); ( aka ithread->new() )
 374  * Called in context of parent thread
 375  */
 376
 377 SV *
 378 Perl_ithread_create(pTHX_ SV *obj, char* classname, SV* init_function, SV* params)
 379 {
 380         ithread*        thread;
 381         CLONE_PARAMS    clone_param;
 382         ithread*        current_thread;
 383
 384         SV**            tmps_tmp = PL_tmps_stack;
 385         I32             tmps_ix  = PL_tmps_ix;
 386
 387         PERL_THREAD_GETSPECIFIC(self_key,current_thread);
 388         MUTEX_LOCK(&create_destruct_mutex);
 389         thread = PerlMemShared_malloc(sizeof(ithread));
 390         Zero(thread,1,ithread);
 391         thread->next = threads;
 392         thread->prev = threads->prev;
 393         threads->prev = thread;
 394         thread->prev->next = thread;
 395         /* Set count to 1 immediately in case thread exits before
 396          * we return to caller !
 397          */
 398         thread->count = 1;
 399         MUTEX_INIT(&thread->mutex);
 400         thread->tid = tid_counter++;
 401         thread->gimme = GIMME_V;
 402
 403         /* "Clone" our interpreter into the thread's interpreter
 404          * This gives thread access to "static data" and code.
 405          */
 406
 407         PerlIO_flush((PerlIO*)NULL);
 408         PERL_THREAD_SETSPECIFIC(self_key,thread);
 409
 410         SAVEBOOL(PL_srand_called); /* Save this so it becomes the correct
 411                                       value */
 412         PL_srand_called = FALSE; /* Set it to false so we can detect
 413                                     if it gets set during the clone */
 414
 415 #ifdef WIN32
 416         thread->interp = perl_clone(aTHX, CLONEf_KEEP_PTR_TABLE | CLONEf_CLONE_HOST);
 417 #else
 418         thread->interp = perl_clone(aTHX, CLONEf_KEEP_PTR_TABLE);
 419 #endif
 420         /* perl_clone leaves us in new interpreter's context.
 421            As it is tricky to spot an implicit aTHX, create a new scope
 422            with aTHX matching the context for the duration of
 423            our work for new interpreter.
 424          */
 425         {
 426             dTHXa(thread->interp);
 427
 428             /* Here we remove END blocks since they should only run
 429                in the thread they are created
 430             */
 431             SvREFCNT_dec(PL_endav);
 432             PL_endav = newAV();
 433             clone_param.flags = 0;
 434             thread->init_function = sv_dup(init_function, &clone_param);
 435             if (SvREFCNT(thread->init_function) == 0) {
 436                 SvREFCNT_inc(thread->init_function);
 437             }
 438
 439
 440
 441             thread->params = sv_dup(params, &clone_param);
 442             SvREFCNT_inc(thread->params);
 443
 444
 445             /* The code below checks that anything living on
 446                the tmps stack and has been cloned (so it lives in the
 447                ptr_table) has a refcount higher than 0
 448
 449                If the refcount is 0 it means that a something on the
 450                stack/context was holding a reference to it and
 451                since we init_stacks() in perl_clone that won't get
 452                cleaned and we will get a leaked scalar.
 453                The reason it was cloned was that it lived on the
 454                @_ stack.
 455
 456                Example of this can be found in bugreport 15837
 457                where calls in the parameter list end up as a temp
 458
 459                One could argue that this fix should be in perl_clone
 460             */
 461
 462
 463             while (tmps_ix > 0) {
 464               SV* sv = (SV*)ptr_table_fetch(PL_ptr_table, tmps_tmp[tmps_ix]);
 465               tmps_ix--;
 466               if (sv && SvREFCNT(sv) == 0) {
 467                 SvREFCNT_inc(sv);
 468                 SvREFCNT_dec(sv);
 469               }
 470             }
 471
 472
 473
 474             SvTEMP_off(thread->init_function);
 475             ptr_table_free(PL_ptr_table);
 476             PL_ptr_table = NULL;
 477             PL_exit_flags |= PERL_EXIT_DESTRUCT_END;
 478         }
 479         PERL_THREAD_SETSPECIFIC(self_key,current_thread);
 480         PERL_SET_CONTEXT(aTHX);
 481
 482         /* Start the thread */
 483
 484 #ifdef WIN32
 485
 486         thread->handle = CreateThread(NULL, 0, Perl_ithread_run,
 487                         (LPVOID)thread, 0, &thread->thr);
 488
 489 #else
 490         {
 491           static pthread_attr_t attr;
 492           static int attr_inited = 0;
 493           static int attr_joinable = PTHREAD_CREATE_JOINABLE;
 494           if (!attr_inited) {
 495             attr_inited = 1;
 496             pthread_attr_init(&attr);
 497           }
 498 #  ifdef PTHREAD_ATTR_SETDETACHSTATE
 499             PTHREAD_ATTR_SETDETACHSTATE(&attr, attr_joinable);
 500 #  endif
 501 #  ifdef THREAD_CREATE_NEEDS_STACK
 502             if(pthread_attr_setstacksize(&attr, THREAD_CREATE_NEEDS_STACK))
 503               Perl_croak(aTHX_ "panic: pthread_attr_setstacksize failed");
 504 #  endif
 505
 506 #ifdef OLD_PTHREADS_API
 507           pthread_create( &thread->thr, attr, Perl_ithread_run, (void *)thread);
 508 #else
 509 #  if defined(HAS_PTHREAD_ATTR_SETSCOPE) && defined(PTHREAD_SCOPE_SYSTEM)
 510           pthread_attr_setscope( &attr, PTHREAD_SCOPE_SYSTEM );
 511 #  endif
 512           pthread_create( &thread->thr, &attr, Perl_ithread_run, (void *)thread);
 513 #endif
 514         }
 515 #endif
 516         known_threads++;
 517         active_threads++;
 518         MUTEX_UNLOCK(&create_destruct_mutex);
 519         sv_2mortal(params);
 520
 521         return ithread_to_SV(aTHX_ obj, thread, classname, FALSE);
 522 }
 523
 524 SV*
 525 Perl_ithread_self (pTHX_ SV *obj, char* Class)
 526 {
 527     ithread *thread;
 528 #ifdef OEMVS
 529     void *ptr;
 530     PERL_THREAD_GETSPECIFIC(self_key,ptr);
 531     thread = (ithread *) ptr;
 532 #else
 533     PERL_THREAD_GETSPECIFIC(self_key,thread);
 534 #endif
 535    if (thread)
 536         return ithread_to_SV(aTHX_ obj, thread, Class, TRUE);
 537    else
 538         Perl_croak(aTHX_ "panic: cannot find thread data");
 539 }
 540
 541 /*
 542  * Joins the thread this code needs to take the returnvalue from the
 543  * call_sv and send it back
 544  */
 545
 546 void
 547 Perl_ithread_CLONE(pTHX_ SV *obj)
 548 {
 549  if (SvROK(obj))
 550   {
 551    ithread *thread = SV_to_ithread(aTHX_ obj);
 552   }
 553  else
 554   {
 555    Perl_warn(aTHX_ "CLONE %" SVf,obj);
 556   }
 557 }
 558
 559 AV*
 560 Perl_ithread_join(pTHX_ SV *obj)
 561 {
 562     ithread *thread = SV_to_ithread(aTHX_ obj);
 563     MUTEX_LOCK(&thread->mutex);
 564     if (thread->state & PERL_ITHR_DETACHED) {
 565         MUTEX_UNLOCK(&thread->mutex);
 566         Perl_croak(aTHX_ "Cannot join a detached thread");
 567     }
 568     else if (thread->state & PERL_ITHR_JOINED) {
 569         MUTEX_UNLOCK(&thread->mutex);
 570         Perl_croak(aTHX_ "Thread already joined");
 571     }
 572     else {
 573         AV* retparam;
 574 #ifdef WIN32
 575         DWORD waitcode;
 576 #else
 577         void *retval;
 578 #endif
 579         MUTEX_UNLOCK(&thread->mutex);
 580 #ifdef WIN32
 581         waitcode = WaitForSingleObject(thread->handle, INFINITE);
 582 #else
 583         pthread_join(thread->thr,&retval);
 584 #endif
 585         MUTEX_LOCK(&thread->mutex);
 586
 587         /* sv_dup over the args */
 588         {
 589           ithread*        current_thread;
 590           AV* params = (AV*) SvRV(thread->params);
 591           CLONE_PARAMS clone_params;
 592           clone_params.stashes = newAV();
 593           clone_params.flags |= CLONEf_JOIN_IN;
 594           PL_ptr_table = ptr_table_new();
 595           PERL_THREAD_GETSPECIFIC(self_key,current_thread);
 596           PERL_THREAD_SETSPECIFIC(self_key,thread);
 597
 598 #if 0
 599           {
 600             I32 len = av_len(params)+1;
 601             I32 i;
 602             for(i = 0; i < len; i++) {
 603               sv_dump(SvRV(AvARRAY(params)[i]));
 604             }
 605           }
 606 #endif
 607           retparam = (AV*) sv_dup((SV*)params, &clone_params);
 608 #if 0
 609           {
 610             I32 len = av_len(retparam)+1;
 611             I32 i;
 612             for(i = 0; i < len; i++) {
 613                 sv_dump(SvRV(AvARRAY(retparam)[i]));
 614             }
 615           }
 616 #endif
 617           PERL_THREAD_SETSPECIFIC(self_key,current_thread);
 618           SvREFCNT_dec(clone_params.stashes);
 619           SvREFCNT_inc(retparam);
 620           ptr_table_free(PL_ptr_table);
 621           PL_ptr_table = NULL;
 622
 623         }
 624         /* We are finished with it */
 625         thread->state |= PERL_ITHR_JOINED;
 626         MUTEX_UNLOCK(&thread->mutex);
 627
 628         return retparam;
 629     }
 630     return (AV*)NULL;
 631 }
 632
 633 void
 634 Perl_ithread_DESTROY(pTHX_ SV *sv)
 635 {
 636     ithread *thread = SV_to_ithread(aTHX_ sv);
 637     sv_unmagic(SvRV(sv),PERL_MAGIC_shared_scalar);
 638 }
 639
 640 #endif /* USE_ITHREADS */
 641
 642 MODULE = threads                PACKAGE = threads       PREFIX = ithread_
 643 PROTOTYPES: DISABLE
 644
 645 #ifdef USE_ITHREADS
 646
 647 void
 648 ithread_new (classname, function_to_call, ...)
 649 char *  classname
 650 SV *    function_to_call
 651 CODE:
 652 {
 653     AV* params = newAV();
 654     if (items > 2) {
 655         int i;
 656         for(i = 2; i < items ; i++) {
 657             av_push(params, SvREFCNT_inc(ST(i)));
 658         }
 659     }
 660     ST(0) = sv_2mortal(Perl_ithread_create(aTHX_ Nullsv, classname, function_to_call, newRV_noinc((SV*) params)));
 661     XSRETURN(1);
 662 }
 663
 664 void
 665 ithread_list(char *classname)
 666 PPCODE:
 667 {
 668   ithread *curr_thread;
 669   MUTEX_LOCK(&create_destruct_mutex);
 670   curr_thread = threads;
 671   if(curr_thread->tid != 0)
 672     PUSHs( sv_2mortal(ithread_to_SV(aTHX_ NULL, curr_thread, classname, TRUE)));
 673   while(curr_thread) {
 674     curr_thread = curr_thread->next;
 675     if(curr_thread == threads)
 676       break;
 677     if(curr_thread->state & PERL_ITHR_DETACHED ||
 678        curr_thread->state & PERL_ITHR_JOINED)
 679          continue;
 680      PUSHs( sv_2mortal(ithread_to_SV(aTHX_ NULL, curr_thread, classname, TRUE)));
 681   }
 682   MUTEX_UNLOCK(&create_destruct_mutex);
 683 }
 684
 685
 686 void
 687 ithread_self(char *classname)
 688 CODE:
 689 {
 690         ST(0) = sv_2mortal(Perl_ithread_self(aTHX_ Nullsv,classname));
 691         XSRETURN(1);
 692 }
 693
 694 int
 695 ithread_tid(ithread *thread)
 696
 697 void
 698 ithread_join(SV *obj)
 699 PPCODE:
 700 {
 701   AV* params = Perl_ithread_join(aTHX_ obj);
 702   int i;
 703   I32 len = AvFILL(params);
 704   for (i = 0; i <= len; i++) {
 705     SV* tmp = av_shift(params);
 706     XPUSHs(tmp);
 707     sv_2mortal(tmp);
 708   }
 709   SvREFCNT_dec(params);
 710 }
 711
 712 void
 713 yield(...)
 714 CODE:
 715 {
 716     YIELD;
 717 }
 718
 719
 720 void
 721 ithread_detach(ithread *thread)
 722
 723 void
 724 ithread_DESTROY(SV *thread)
 725
 726 #endif /* USE_ITHREADS */
 727
 728 BOOT:
 729 {
 730 #ifdef USE_ITHREADS
 731         ithread* thread;
 732         PL_perl_destruct_level = 2;
 733         PERL_THREAD_ALLOC_SPECIFIC(self_key);
 734         MUTEX_INIT(&create_destruct_mutex);
 735         MUTEX_LOCK(&create_destruct_mutex);
 736         PL_threadhook = &Perl_ithread_hook;
 737         thread  = PerlMemShared_malloc(sizeof(ithread));
 738         Zero(thread,1,ithread);
 739         PL_perl_destruct_level = 2;
 740         MUTEX_INIT(&thread->mutex);
 741         threads = thread;
 742         thread->next = thread;
 743         thread->prev = thread;
 744         thread->interp = aTHX;
 745         thread->count  = 1;  /* Immortal. */
 746         thread->tid = tid_counter++;
 747         known_threads++;
 748         active_threads++;
 749         thread->state = PERL_ITHR_DETACHED;
 750 #ifdef WIN32
 751         thread->thr = GetCurrentThreadId();
 752 #else
 753         thread->thr = pthread_self();
 754 #endif
 755
 756         PERL_THREAD_SETSPECIFIC(self_key,thread);
 757         MUTEX_UNLOCK(&create_destruct_mutex);
 758 #endif /* USE_ITHREADS */
 759 }
 760