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 #ifdef OEMVS
  50 #   define PERL_THREAD_GETSPECIFIC_THREAD(k, t) STMT_START { void *gsptr; PERL_THREAD_GETSPECIFIC(k, gsptr); t = (ithread *) gsptr; } STMT_END
  51 #else
  52 #   define PERL_THREAD_GETSPECIFIC_THREAD(k, t) PERL_THREAD_GETSPECIFIC(k, t)
  53 #endif
  54
  55 /* Values for 'state' member */
  56 #define PERL_ITHR_JOINABLE              0
  57 #define PERL_ITHR_DETACHED              1
  58 #define PERL_ITHR_FINISHED              4
  59 #define PERL_ITHR_JOINED                2
  60
  61 typedef struct ithread_s {
  62     struct ithread_s *next;     /* Next thread in the list */
  63     struct ithread_s *prev;     /* Prev thread in the list */
  64     PerlInterpreter *interp;    /* The threads interpreter */
  65     I32 tid;                    /* Threads module's thread id */
  66     perl_mutex mutex;           /* Mutex for updating things in this struct */
  67     I32 count;                  /* How many SVs have a reference to us */
  68     signed char state;          /* Are we detached ? */
  69     int gimme;                  /* Context of create */
  70     SV* init_function;          /* Code to run */
  71     SV* params;                 /* Args to pass function */
  72 #ifdef WIN32
  73         DWORD   thr;            /* OS's idea if thread id */
  74         HANDLE handle;          /* OS's waitable handle */
  75 #else
  76         pthread_t thr;          /* OS's handle for the thread */
  77 #endif
  78 } ithread;
  79
  80 ithread *threads;
  81
  82 /* Macros to supply the aTHX_ in an embed.h like manner */
  83 #define ithread_join(thread)            Perl_ithread_join(aTHX_ thread)
  84 #define ithread_DESTROY(thread)         Perl_ithread_DESTROY(aTHX_ thread)
  85 #define ithread_CLONE(thread)           Perl_ithread_CLONE(aTHX_ thread)
  86 #define ithread_detach(thread)          Perl_ithread_detach(aTHX_ thread)
  87 #define ithread_tid(thread)             ((thread)->tid)
  88 #define ithread_yield(thread)           (YIELD);
  89
  90 static perl_mutex create_destruct_mutex;  /* protects the creation and destruction of threads*/
  91
  92 I32 tid_counter = 0;
  93 I32 known_threads = 0;
  94 I32 active_threads = 0;
  95 perl_key self_key;
  96
  97 /*
  98  *  Clear up after thread is done with
  99  */
 100 void
 101 Perl_ithread_destruct (pTHX_ ithread* thread, const char *why)
 102 {
 103         MUTEX_LOCK(&thread->mutex);
 104         if (!thread->next) {
 105             Perl_croak(aTHX_ "panic: destruct destroyed thread %p (%s)",thread, why);
 106         }
 107         if (thread->count != 0) {
 108                 MUTEX_UNLOCK(&thread->mutex);
 109                 return;
 110         }
 111         MUTEX_LOCK(&create_destruct_mutex);
 112         /* Remove from circular list of threads */
 113         if (thread->next == thread) {
 114             /* last one should never get here ? */
 115             threads = NULL;
 116         }
 117         else {
 118             thread->next->prev = thread->prev;
 119             thread->prev->next = thread->next;
 120             if (threads == thread) {
 121                 threads = thread->next;
 122             }
 123             thread->next = NULL;
 124             thread->prev = NULL;
 125         }
 126         known_threads--;
 127         assert( known_threads >= 0 );
 128 #if 0
 129         Perl_warn(aTHX_ "destruct %d @ %p by %p now %d",
 130                   thread->tid,thread->interp,aTHX, known_threads);
 131 #endif
 132         MUTEX_UNLOCK(&create_destruct_mutex);
 133         /* Thread is now disowned */
 134
 135         if(thread->interp) {
 136             dTHXa(thread->interp);
 137             ithread*        current_thread;
 138 #ifdef OEMVS
 139             void *ptr;
 140 #endif
 141             PERL_SET_CONTEXT(thread->interp);
 142             PERL_THREAD_GETSPECIFIC_THREAD(self_key, current_thread);
 143             PERL_THREAD_SETSPECIFIC(self_key,thread);
 144
 145
 146
 147             SvREFCNT_dec(thread->params);
 148
 149
 150
 151             thread->params = Nullsv;
 152             perl_destruct(thread->interp);
 153             perl_free(thread->interp);
 154             thread->interp = NULL;
 155             PERL_THREAD_SETSPECIFIC(self_key,current_thread);
 156
 157         }
 158         MUTEX_UNLOCK(&thread->mutex);
 159         MUTEX_DESTROY(&thread->mutex);
 160         PerlMemShared_free(thread);
 161
 162         PERL_SET_CONTEXT(aTHX);
 163 }
 164
 165 int
 166 Perl_ithread_hook(pTHX)
 167 {
 168     int veto_cleanup = 0;
 169     MUTEX_LOCK(&create_destruct_mutex);
 170     if (aTHX == PL_curinterp && active_threads != 1) {
 171         Perl_warn(aTHX_ "A thread exited while %" IVdf " threads were running",
 172                                                 (IV)active_threads);
 173         veto_cleanup = 1;
 174     }
 175     MUTEX_UNLOCK(&create_destruct_mutex);
 176     return veto_cleanup;
 177 }
 178
 179 void
 180 Perl_ithread_detach(pTHX_ ithread *thread)
 181 {
 182     MUTEX_LOCK(&thread->mutex);
 183     if (!(thread->state & (PERL_ITHR_DETACHED|PERL_ITHR_JOINED))) {
 184         thread->state |= PERL_ITHR_DETACHED;
 185 #ifdef WIN32
 186         CloseHandle(thread->handle);
 187         thread->handle = 0;
 188 #else
 189         PERL_THREAD_DETACH(thread->thr);
 190 #endif
 191     }
 192     if ((thread->state & PERL_ITHR_FINISHED) &&
 193         (thread->state & PERL_ITHR_DETACHED)) {
 194         MUTEX_UNLOCK(&thread->mutex);
 195         Perl_ithread_destruct(aTHX_ thread, "detach");
 196     }
 197     else {
 198         MUTEX_UNLOCK(&thread->mutex);
 199     }
 200 }
 201
 202 /* MAGIC (in mg.h sense) hooks */
 203
 204 int
 205 ithread_mg_get(pTHX_ SV *sv, MAGIC *mg)
 206 {
 207     ithread *thread = (ithread *) mg->mg_ptr;
 208     SvIVX(sv) = PTR2IV(thread);
 209     SvIOK_on(sv);
 210     return 0;
 211 }
 212
 213 int
 214 ithread_mg_free(pTHX_ SV *sv, MAGIC *mg)
 215 {
 216     ithread *thread = (ithread *) mg->mg_ptr;
 217     MUTEX_LOCK(&thread->mutex);
 218     thread->count--;
 219     if (thread->count == 0) {
 220        if(thread->state & PERL_ITHR_FINISHED &&
 221           (thread->state & PERL_ITHR_DETACHED ||
 222            thread->state & PERL_ITHR_JOINED))
 223        {
 224             MUTEX_UNLOCK(&thread->mutex);
 225             Perl_ithread_destruct(aTHX_ thread, "no reference");
 226        }
 227        else {
 228             MUTEX_UNLOCK(&thread->mutex);
 229        }
 230     }
 231     else {
 232         MUTEX_UNLOCK(&thread->mutex);
 233     }
 234     return 0;
 235 }
 236
 237 int
 238 ithread_mg_dup(pTHX_ MAGIC *mg, CLONE_PARAMS *param)
 239 {
 240     ithread *thread = (ithread *) mg->mg_ptr;
 241     MUTEX_LOCK(&thread->mutex);
 242     thread->count++;
 243     MUTEX_UNLOCK(&thread->mutex);
 244     return 0;
 245 }
 246
 247 MGVTBL ithread_vtbl = {
 248  ithread_mg_get,        /* get */
 249  0,                     /* set */
 250  0,                     /* len */
 251  0,                     /* clear */
 252  ithread_mg_free,       /* free */
 253  0,                     /* copy */
 254  ithread_mg_dup         /* dup */
 255 };
 256
 257
 258 /*
 259  *      Starts executing the thread. Needs to clean up memory a tad better.
 260  *      Passed as the C level function to run in the new thread
 261  */
 262
 263 #ifdef WIN32
 264 THREAD_RET_TYPE
 265 Perl_ithread_run(LPVOID arg) {
 266 #else
 267 void*
 268 Perl_ithread_run(void * arg) {
 269 #endif
 270         ithread* thread = (ithread*) arg;
 271         dTHXa(thread->interp);
 272         PERL_SET_CONTEXT(thread->interp);
 273         PERL_THREAD_SETSPECIFIC(self_key,thread);
 274
 275 #if 0
 276         /* Far from clear messing with ->thr child-side is a good idea */
 277         MUTEX_LOCK(&thread->mutex);
 278 #ifdef WIN32
 279         thread->thr = GetCurrentThreadId();
 280 #else
 281         thread->thr = pthread_self();
 282 #endif
 283         MUTEX_UNLOCK(&thread->mutex);
 284 #endif
 285
 286         PL_perl_destruct_level = 2;
 287
 288         {
 289                 AV* params = (AV*) SvRV(thread->params);
 290                 I32 len = av_len(params)+1;
 291                 int i;
 292                 dSP;
 293                 ENTER;
 294                 SAVETMPS;
 295                 PUSHMARK(SP);
 296                 for(i = 0; i < len; i++) {
 297                     XPUSHs(av_shift(params));
 298                 }
 299                 PUTBACK;
 300                 len = call_sv(thread->init_function, thread->gimme|G_EVAL);
 301
 302                 SPAGAIN;
 303                 for (i=len-1; i >= 0; i--) {
 304                   SV *sv = POPs;
 305                   av_store(params, i, SvREFCNT_inc(sv));
 306                 }
 307                 if (SvTRUE(ERRSV)) {
 308                     Perl_warn(aTHX_ "thread failed to start: %" SVf, ERRSV);
 309                 }
 310                 FREETMPS;
 311                 LEAVE;
 312                 SvREFCNT_dec(thread->init_function);
 313         }
 314
 315         PerlIO_flush((PerlIO*)NULL);
 316         MUTEX_LOCK(&thread->mutex);
 317         thread->state |= PERL_ITHR_FINISHED;
 318
 319         if (thread->state & PERL_ITHR_DETACHED) {
 320                 MUTEX_UNLOCK(&thread->mutex);
 321                 Perl_ithread_destruct(aTHX_ thread, "detached finish");
 322         } else {
 323                 MUTEX_UNLOCK(&thread->mutex);
 324         }
 325         MUTEX_LOCK(&create_destruct_mutex);
 326         active_threads--;
 327         assert( active_threads >= 0 );
 328         MUTEX_UNLOCK(&create_destruct_mutex);
 329
 330 #ifdef WIN32
 331         return (DWORD)0;
 332 #else
 333         return 0;
 334 #endif
 335 }
 336
 337 SV *
 338 ithread_to_SV(pTHX_ SV *obj, ithread *thread, char *classname, bool inc)
 339 {
 340     SV *sv;
 341     MAGIC *mg;
 342     if (inc) {
 343         MUTEX_LOCK(&thread->mutex);
 344         thread->count++;
 345         MUTEX_UNLOCK(&thread->mutex);
 346     }
 347     if (!obj)
 348      obj = newSV(0);
 349     sv = newSVrv(obj,classname);
 350     sv_setiv(sv,PTR2IV(thread));
 351     mg = sv_magicext(sv,Nullsv,PERL_MAGIC_shared_scalar,&ithread_vtbl,(char *)thread,0);
 352     mg->mg_flags |= MGf_DUP;
 353     SvREADONLY_on(sv);
 354     return obj;
 355 }
 356
 357 ithread *
 358 SV_to_ithread(pTHX_ SV *sv)
 359 {
 360     ithread *thread;
 361     if (SvROK(sv))
 362      {
 363       thread = INT2PTR(ithread*, SvIV(SvRV(sv)));
 364      }
 365     else
 366      {
 367       PERL_THREAD_GETSPECIFIC_THREAD(self_key, thread);
 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_THREAD(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    PERL_THREAD_GETSPECIFIC_THREAD(self_key, thread);
 529    if (thread)
 530         return ithread_to_SV(aTHX_ obj, thread, Class, TRUE);
 531    else
 532         Perl_croak(aTHX_ "panic: cannot find thread data");
 533 }
 534
 535 /*
 536  * Joins the thread this code needs to take the returnvalue from the
 537  * call_sv and send it back
 538  */
 539
 540 void
 541 Perl_ithread_CLONE(pTHX_ SV *obj)
 542 {
 543  if (SvROK(obj))
 544   {
 545    ithread *thread = SV_to_ithread(aTHX_ obj);
 546   }
 547  else
 548   {
 549    Perl_warn(aTHX_ "CLONE %" SVf,obj);
 550   }
 551 }
 552
 553 AV*
 554 Perl_ithread_join(pTHX_ SV *obj)
 555 {
 556     ithread *thread = SV_to_ithread(aTHX_ obj);
 557     MUTEX_LOCK(&thread->mutex);
 558     if (thread->state & PERL_ITHR_DETACHED) {
 559         MUTEX_UNLOCK(&thread->mutex);
 560         Perl_croak(aTHX_ "Cannot join a detached thread");
 561     }
 562     else if (thread->state & PERL_ITHR_JOINED) {
 563         MUTEX_UNLOCK(&thread->mutex);
 564         Perl_croak(aTHX_ "Thread already joined");
 565     }
 566     else {
 567         AV* retparam;
 568 #ifdef WIN32
 569         DWORD waitcode;
 570 #else
 571         void *retval;
 572 #endif
 573         MUTEX_UNLOCK(&thread->mutex);
 574 #ifdef WIN32
 575         waitcode = WaitForSingleObject(thread->handle, INFINITE);
 576 #else
 577         pthread_join(thread->thr,&retval);
 578 #endif
 579         MUTEX_LOCK(&thread->mutex);
 580
 581         /* sv_dup over the args */
 582         {
 583           ithread*        current_thread;
 584           AV* params = (AV*) SvRV(thread->params);
 585           CLONE_PARAMS clone_params;
 586           clone_params.stashes = newAV();
 587           clone_params.flags |= CLONEf_JOIN_IN;
 588           PL_ptr_table = ptr_table_new();
 589           PERL_THREAD_GETSPECIFIC_THREAD(self_key, current_thread);
 590           PERL_THREAD_SETSPECIFIC(self_key,thread);
 591
 592 #if 0
 593           {
 594             I32 len = av_len(params)+1;
 595             I32 i;
 596             for(i = 0; i < len; i++) {
 597               sv_dump(SvRV(AvARRAY(params)[i]));
 598             }
 599           }
 600 #endif
 601           retparam = (AV*) sv_dup((SV*)params, &clone_params);
 602 #if 0
 603           {
 604             I32 len = av_len(retparam)+1;
 605             I32 i;
 606             for(i = 0; i < len; i++) {
 607                 sv_dump(SvRV(AvARRAY(retparam)[i]));
 608             }
 609           }
 610 #endif
 611           PERL_THREAD_SETSPECIFIC(self_key,current_thread);
 612           SvREFCNT_dec(clone_params.stashes);
 613           SvREFCNT_inc(retparam);
 614           ptr_table_free(PL_ptr_table);
 615           PL_ptr_table = NULL;
 616
 617         }
 618         /* We are finished with it */
 619         thread->state |= PERL_ITHR_JOINED;
 620         MUTEX_UNLOCK(&thread->mutex);
 621
 622         return retparam;
 623     }
 624     return (AV*)NULL;
 625 }
 626
 627 void
 628 Perl_ithread_DESTROY(pTHX_ SV *sv)
 629 {
 630     ithread *thread = SV_to_ithread(aTHX_ sv);
 631     sv_unmagic(SvRV(sv),PERL_MAGIC_shared_scalar);
 632 }
 633
 634 #endif /* USE_ITHREADS */
 635
 636 MODULE = threads                PACKAGE = threads       PREFIX = ithread_
 637 PROTOTYPES: DISABLE
 638
 639 #ifdef USE_ITHREADS
 640
 641 void
 642 ithread_new (classname, function_to_call, ...)
 643 char *  classname
 644 SV *    function_to_call
 645 CODE:
 646 {
 647     AV* params = newAV();
 648     if (items > 2) {
 649         int i;
 650         for(i = 2; i < items ; i++) {
 651             av_push(params, SvREFCNT_inc(ST(i)));
 652         }
 653     }
 654     ST(0) = sv_2mortal(Perl_ithread_create(aTHX_ Nullsv, classname, function_to_call, newRV_noinc((SV*) params)));
 655     XSRETURN(1);
 656 }
 657
 658 void
 659 ithread_list(char *classname)
 660 PPCODE:
 661 {
 662   ithread *curr_thread;
 663   MUTEX_LOCK(&create_destruct_mutex);
 664   curr_thread = threads;
 665   if(curr_thread->tid != 0)
 666     XPUSHs( sv_2mortal(ithread_to_SV(aTHX_ NULL, curr_thread, classname, TRUE)));
 667   while(curr_thread) {
 668     curr_thread = curr_thread->next;
 669     if(curr_thread == threads)
 670       break;
 671     if(curr_thread->state & PERL_ITHR_DETACHED ||
 672        curr_thread->state & PERL_ITHR_JOINED)
 673          continue;
 674      XPUSHs( sv_2mortal(ithread_to_SV(aTHX_ NULL, curr_thread, classname, TRUE)));
 675   }
 676   MUTEX_UNLOCK(&create_destruct_mutex);
 677 }
 678
 679
 680 void
 681 ithread_self(char *classname)
 682 CODE:
 683 {
 684         ST(0) = sv_2mortal(Perl_ithread_self(aTHX_ Nullsv,classname));
 685         XSRETURN(1);
 686 }
 687
 688 int
 689 ithread_tid(ithread *thread)
 690
 691 void
 692 ithread_join(SV *obj)
 693 PPCODE:
 694 {
 695   AV* params = Perl_ithread_join(aTHX_ obj);
 696   int i;
 697   I32 len = AvFILL(params);
 698   for (i = 0; i <= len; i++) {
 699     SV* tmp = av_shift(params);
 700     XPUSHs(tmp);
 701     sv_2mortal(tmp);
 702   }
 703   SvREFCNT_dec(params);
 704 }
 705
 706 void
 707 yield(...)
 708 CODE:
 709 {
 710     YIELD;
 711 }
 712
 713
 714 void
 715 ithread_detach(ithread *thread)
 716
 717 void
 718 ithread_DESTROY(SV *thread)
 719
 720 #endif /* USE_ITHREADS */
 721
 722 BOOT:
 723 {
 724 #ifdef USE_ITHREADS
 725         ithread* thread;
 726         PL_perl_destruct_level = 2;
 727         PERL_THREAD_ALLOC_SPECIFIC(self_key);
 728         MUTEX_INIT(&create_destruct_mutex);
 729         MUTEX_LOCK(&create_destruct_mutex);
 730         PL_threadhook = &Perl_ithread_hook;
 731         thread  = PerlMemShared_malloc(sizeof(ithread));
 732         Zero(thread,1,ithread);
 733         PL_perl_destruct_level = 2;
 734         MUTEX_INIT(&thread->mutex);
 735         threads = thread;
 736         thread->next = thread;
 737         thread->prev = thread;
 738         thread->interp = aTHX;
 739         thread->count  = 1;  /* Immortal. */
 740         thread->tid = tid_counter++;
 741         known_threads++;
 742         active_threads++;
 743         thread->state = PERL_ITHR_DETACHED;
 744 #ifdef WIN32
 745         thread->thr = GetCurrentThreadId();
 746 #else
 747         thread->thr = pthread_self();
 748 #endif
 749
 750         PERL_THREAD_SETSPECIFIC(self_key,thread);
 751         MUTEX_UNLOCK(&create_destruct_mutex);
 752 #endif /* USE_ITHREADS */
 753 }
 754