3 * Copyright (c) 2001-2002, 2006 Larry Wall
5 * You may distribute under the terms of either the GNU General Public
6 * License or the Artistic License, as specified in the README file.
8 * "Hand any two wizards a piece of rope and they would instinctively pull in
9 * opposite directions."
12 * Contributed by Artur Bergman <sky AT crucially DOT net>
13 * Pulled in the (an)other direction by Nick Ing-Simmons
14 * <nick AT ing-simmons DOT net>
15 * CPAN version produced by Jerry D. Hedden <jdhedden AT cpan DOT org>
19 * Shared variables are implemented by a scheme similar to tieing.
20 * Each thread has a proxy SV with attached magic -- "private SVs" --
21 * which all point to a single SV in a separate shared interpreter
22 * (PL_sharedsv_space) -- "shared SVs".
24 * The shared SV holds the variable's true values, and its state is
25 * copied between the shared and private SVs with the usual
26 * mg_get()/mg_set() arrangement.
28 * Aggregates (AVs and HVs) are implemented using tie magic, except that
29 * the vtable used is one defined in this file rather than the standard one.
30 * This means that where a tie function like FETCH is normally invoked by
31 * the tie magic's mg_get() function, we completely bypass the calling of a
32 * perl-level function, and directly call C-level code to handle it. On
33 * the other hand, calls to functions like PUSH are done directly by code
34 * in av.c, etc., which we can't bypass. So the best we can do is to provide
35 * XS versions of these functions. We also have to attach a tie object,
36 * blessed into the class threads::shared::tie, to keep the method-calling
39 * Access to aggregate elements is done the usual tied way by returning a
40 * proxy PVLV element with attached element magic.
42 * Pointers to the shared SV are squirrelled away in the mg->mg_ptr field
43 * of magic (with mg_len == 0), and in the IV2PTR(SvIV(sv)) field of tied
44 * object SVs. These pointers have to be hidden like this because they
45 * cross interpreter boundaries, and we don't want sv_clear() and friends
48 * The three basic shared types look like the following:
52 * Shared scalar (my $s : shared):
54 * SV = PVMG(0x7ba238) at 0x7387a8
55 * FLAGS = (PADMY,GMG,SMG)
57 * MG_TYPE = PERL_MAGIC_shared_scalar(n)
58 * MG_PTR = 0x810358 <<<< pointer to the shared SV
62 * Shared aggregate (my @a : shared; my %h : shared):
64 * SV = PVAV(0x7175d0) at 0x738708
67 * MG_TYPE = PERL_MAGIC_tied(P)
68 * MG_OBJ = 0x7136e0 <<<< ref to the tied object
69 * SV = RV(0x7136f0) at 0x7136e0
71 * SV = PVMG(0x7ba238) at 0x738640 <<<< the tied object
72 * FLAGS = (OBJECT,IOK,pIOK)
73 * IV = 8455000 <<<< pointer to the shared AV
74 * STASH = 0x80abf0 "threads::shared::tie"
75 * MG_PTR = 0x810358 "" <<<< another pointer to the shared AV
80 * Aggregate element (my @a : shared; $a[0])
82 * SV = PVLV(0x77f628) at 0x713550
83 * FLAGS = (GMG,SMG,RMG,pIOK)
85 * MG_TYPE = PERL_MAGIC_shared_scalar(n)
86 * MG_PTR = 0x8103c0 "" <<<< pointer to the shared element
88 * MG_TYPE = PERL_MAGIC_tiedelem(p)
89 * MG_OBJ = 0x7136e0 <<<< ref to the tied object
90 * SV = RV(0x7136f0) at 0x7136e0
92 * SV = PVMG(0x7ba278) at 0x738660 <<<< the tied object
93 * FLAGS = (OBJECT,IOK,pIOK)
94 * IV = 8455064 <<<< pointer to the shared AV
95 * STASH = 0x80ac30 "threads::shared::tie"
98 * Note that PERL_MAGIC_tiedelem(p) magic doesn't have a pointer to a
99 * shared SV in mg_ptr; instead this is used to store the hash key,
100 * if any, like normal tied elements. Note also that element SVs may have
101 * pointers to both the shared aggregate and the shared element.
106 * If a shared variable is used as a perl-level lock or condition
107 * variable, then PERL_MAGIC_ext magic is attached to the associated
108 * *shared* SV, whose mg_ptr field points to a malloc'ed structure
109 * containing the necessary mutexes and condition variables.
113 * In this file, any variable name prefixed with 's' (e.g., ssv, stmp or sobj)
114 * usually represents a shared SV which corresponds to a private SV named
115 * without the prefix (e.g., sv, tmp or obj).
120 * Perl 5.8.8 contains threads::shared patches up to 26626 (equivalent to
121 * blead patches 26350+26351).
123 * The CPAN version of threads::shared contains the following blead patches:
124 * 26569 (applicable to 5.9.3 only)
130 #define PERL_NO_GET_CONTEXT
135 #define NEED_vnewSVpvf
144 * The shared things need an intepreter to live in ...
146 PerlInterpreter *PL_sharedsv_space; /* The shared sv space */
147 /* To access shared space we fake aTHX in this scope and thread's context */
149 /* Bug #24255: We include ENTER+SAVETMPS/FREETMPS+LEAVE with
150 * SHARED_CONTEXT/CALLER_CONTEXT macros, so that any mortals, etc. created
151 * while in the shared interpreter context don't languish */
153 #define SHARED_CONTEXT \
155 PERL_SET_CONTEXT((aTHX = PL_sharedsv_space)); \
160 /* So we need a way to switch back to the caller's context... */
161 /* So we declare _another_ copy of the aTHX variable ... */
162 #define dTHXc PerlInterpreter *caller_perl = aTHX
164 /* ... and use it to switch back */
165 #define CALLER_CONTEXT \
169 PERL_SET_CONTEXT((aTHX = caller_perl)); \
173 * Only one thread at a time is allowed to mess with shared space.
178 PerlInterpreter *owner;
187 recursive_lock_t PL_sharedsv_lock; /* Mutex protecting the shared sv space */
190 recursive_lock_init(pTHX_ recursive_lock_t *lock)
192 Zero(lock,1,recursive_lock_t);
193 MUTEX_INIT(&lock->mutex);
194 COND_INIT(&lock->cond);
198 recursive_lock_destroy(pTHX_ recursive_lock_t *lock)
200 MUTEX_DESTROY(&lock->mutex);
201 COND_DESTROY(&lock->cond);
205 recursive_lock_release(pTHX_ recursive_lock_t *lock)
207 MUTEX_LOCK(&lock->mutex);
208 if (lock->owner != aTHX) {
209 MUTEX_UNLOCK(&lock->mutex);
210 } else if (--lock->locks == 0) {
212 COND_SIGNAL(&lock->cond);
214 MUTEX_UNLOCK(&lock->mutex);
218 recursive_lock_acquire(pTHX_ recursive_lock_t *lock, char *file, int line)
221 MUTEX_LOCK(&lock->mutex);
222 if (lock->owner == aTHX) {
225 while (lock->owner) {
227 Perl_warn(aTHX_ " %p waiting - owned by %p %s:%d\n",
228 aTHX, lock->owner, lock->file, lock->line);
230 COND_WAIT(&lock->cond,&lock->mutex);
239 MUTEX_UNLOCK(&lock->mutex);
240 SAVEDESTRUCTOR_X(recursive_lock_release,lock);
246 recursive_lock_acquire(aTHX_ &PL_sharedsv_lock, __FILE__, __LINE__);\
249 /* The unlocking is done automatically at scope exit */
250 #define LEAVE_LOCK LEAVE
253 /* A common idiom is to acquire access and switch in ... */
254 #define SHARED_EDIT \
260 /* ... then switch out and release access. */
261 #define SHARED_RELEASE \
269 This structure is attached (using ext magic) to any shared SV that
270 is used by user-level locking or condition code
274 recursive_lock_t lock; /* For user-levl locks */
275 perl_cond user_cond; /* For user-level conditions */
278 /* Magic used for attaching user_lock structs to shared SVs
280 The vtable used has just one entry - when the SV goes away
281 we free the memory for the above.
285 sharedsv_userlock_free(pTHX_ SV *sv, MAGIC *mg)
287 user_lock *ul = (user_lock *) mg->mg_ptr;
288 assert(aTHX == PL_sharedsv_space);
290 recursive_lock_destroy(aTHX_ &ul->lock);
291 COND_DESTROY(&ul->user_cond);
292 PerlMemShared_free(ul);
298 MGVTBL sharedsv_userlock_vtbl = {
303 sharedsv_userlock_free, /* free */
312 * Access to shared things is heavily based on MAGIC
313 * - in mg.h/mg.c/sv.c sense
316 /* In any thread that has access to a shared thing there is a "proxy"
317 for it in its own space which has 'MAGIC' associated which accesses
321 extern MGVTBL sharedsv_scalar_vtbl; /* Scalars have this vtable */
322 extern MGVTBL sharedsv_array_vtbl; /* Hashes and arrays have this
324 extern MGVTBL sharedsv_elem_vtbl; /* Elements of hashes and arrays have
325 this _AS WELL AS_ the scalar magic:
326 The sharedsv_elem_vtbl associates the element with the array/hash and
327 the sharedsv_scalar_vtbl associates it with the value
331 /* Get shared aggregate SV pointed to by threads::shared::tie magic object */
334 S_sharedsv_from_obj(pTHX_ SV *sv)
336 return ((SvROK(sv)) ? INT2PTR(SV *, SvIV(SvRV(sv))) : NULL);
340 /* Return the user_lock structure (if any) associated with a shared SV.
341 * If create is true, create one if it doesn't exist
344 S_get_userlock(pTHX_ SV* ssv, bool create)
347 user_lock *ul = NULL;
350 /* XXX Redesign the storage of user locks so we don't need a global
351 * lock to access them ???? DAPM */
353 mg = mg_find(ssv, PERL_MAGIC_ext);
355 ul = (user_lock*)(mg->mg_ptr);
359 ul = (user_lock *) PerlMemShared_malloc(sizeof(user_lock));
360 Zero(ul, 1, user_lock);
361 /* Attach to shared SV using ext magic */
362 sv_magicext(ssv, NULL, PERL_MAGIC_ext, &sharedsv_userlock_vtbl,
364 recursive_lock_init(aTHX_ &ul->lock);
365 COND_INIT(&ul->user_cond);
373 =for apidoc sharedsv_find
375 Given a private side SV tries to find if the SV has a shared backend,
376 by looking for the magic.
381 Perl_sharedsv_find(pTHX_ SV *sv)
384 if (SvTYPE(sv) >= SVt_PVMG) {
388 if ((mg = mg_find(sv, PERL_MAGIC_tied))
389 && mg->mg_virtual == &sharedsv_array_vtbl) {
390 return ((SV *)mg->mg_ptr);
394 /* This should work for elements as well as they
395 * have scalar magic as well as their element magic
397 if ((mg = mg_find(sv, PERL_MAGIC_shared_scalar))
398 && mg->mg_virtual == &sharedsv_scalar_vtbl) {
399 return ((SV *)mg->mg_ptr);
404 /* Just for tidyness of API also handle tie objects */
405 if (SvROK(sv) && sv_derived_from(sv, "threads::shared::tie")) {
406 return (S_sharedsv_from_obj(aTHX_ sv));
412 /* Associate a private SV with a shared SV by pointing the appropriate
414 * Assumes lock is held.
417 Perl_sharedsv_associate(pTHX_ SV *sv, SV *ssv)
422 /* If we are asked for any private ops we need a thread */
423 assert ( aTHX != PL_sharedsv_space );
425 /* To avoid need for recursive locks require caller to hold lock */
426 assert ( PL_sharedsv_lock.owner == aTHX );
431 if (!(mg = mg_find(sv, PERL_MAGIC_tied))
432 || mg->mg_virtual != &sharedsv_array_vtbl
433 || (SV*) mg->mg_ptr != ssv)
436 sv_setref_iv(obj, "threads::shared::tie", PTR2IV(ssv));
438 sv_unmagic(sv, PERL_MAGIC_tied);
440 mg = sv_magicext(sv, obj, PERL_MAGIC_tied, &sharedsv_array_vtbl,
442 mg->mg_flags |= (MGf_COPY|MGf_DUP);
443 SvREFCNT_inc_void(ssv);
449 if ((SvTYPE(sv) < SVt_PVMG)
450 || !(mg = mg_find(sv, PERL_MAGIC_shared_scalar))
451 || mg->mg_virtual != &sharedsv_scalar_vtbl
452 || (SV*) mg->mg_ptr != ssv)
455 sv_unmagic(sv, PERL_MAGIC_shared_scalar);
457 mg = sv_magicext(sv, Nullsv, PERL_MAGIC_shared_scalar,
458 &sharedsv_scalar_vtbl, (char *)ssv, 0);
459 mg->mg_flags |= (MGf_DUP
464 SvREFCNT_inc_void(ssv);
469 assert ( Perl_sharedsv_find(aTHX_ sv) == ssv );
473 /* Given a private SV, create and return an associated shared SV.
474 * Assumes lock is held.
477 S_sharedsv_new_shared(pTHX_ SV *sv)
482 assert(PL_sharedsv_lock.owner == aTHX);
483 assert(aTHX != PL_sharedsv_space);
487 SvREFCNT(ssv) = 0; /* Will be upped to 1 by Perl_sharedsv_associate */
488 sv_upgrade(ssv, SvTYPE(sv));
490 Perl_sharedsv_associate(aTHX_ sv, ssv);
495 /* Given a shared SV, create and return an associated private SV.
496 * Assumes lock is held.
499 S_sharedsv_new_private(pTHX_ SV *ssv)
503 assert(PL_sharedsv_lock.owner == aTHX);
504 assert(aTHX != PL_sharedsv_space);
507 sv_upgrade(sv, SvTYPE(ssv));
508 Perl_sharedsv_associate(aTHX_ sv, ssv);
513 /* A threadsafe version of SvREFCNT_dec(ssv) */
516 S_sharedsv_dec(pTHX_ SV* ssv)
521 if (SvREFCNT(ssv) > 1) {
522 /* No side effects, so can do it lightweight */
534 /* Implements Perl-level share() and :shared */
537 Perl_sharedsv_share(pTHX_ SV *sv)
541 Perl_croak(aTHX_ "Cannot share globs yet");
545 Perl_croak(aTHX_ "Cannot share subs yet");
550 (void) S_sharedsv_new_shared(aTHX_ sv);
558 #if defined(WIN32) || defined(OS2)
559 # define ABS2RELMILLI(abs) \
561 abs -= (double)time(NULL); \
562 if (abs > 0) { abs *= 1000; } \
565 #endif /* WIN32 || OS2 */
567 /* Do OS-specific condition timed wait */
570 Perl_sharedsv_cond_timedwait(perl_cond *cond, perl_mutex *mut, double abs)
572 #if defined(NETWARE) || defined(FAKE_THREADS) || defined(I_MACH_CTHREADS)
573 Perl_croak_nocontext("cond_timedwait not supported on this platform");
582 /* See comments in win32/win32thread.h COND_WAIT vis-a-vis race */
583 switch (WaitForSingleObject(cond->sem, (DWORD)abs)) {
584 case WAIT_OBJECT_0: got_it = 1; break;
585 case WAIT_TIMEOUT: break;
587 /* WAIT_FAILED? WAIT_ABANDONED? others? */
588 Perl_croak_nocontext("panic: cond_timedwait (%ld)",GetLastError());
601 if ((rc = DosResetEventSem(*cond,&n_a)) && (rc != ERROR_ALREADY_RESET))
602 Perl_rc = rc, croak_with_os2error("panic: cond_timedwait-reset");
604 if (CheckOSError(DosWaitEventSem(*cond,abs))
605 && (rc != ERROR_INTERRUPT))
606 croak_with_os2error("panic: cond_timedwait");
607 if (rc == ERROR_INTERRUPT) errno = EINTR;
610 # else /* Hope you're I_PTHREAD! */
614 ts.tv_sec = (long)abs;
615 abs -= (NV)ts.tv_sec;
616 ts.tv_nsec = (long)(abs * 1000000000.0);
618 switch (pthread_cond_timedwait(cond, mut, &ts)) {
619 case 0: got_it = 1; break;
620 case ETIMEDOUT: break;
623 if (errno == ETIMEDOUT || errno == EAGAIN)
627 Perl_croak_nocontext("panic: cond_timedwait");
633 #endif /* NETWARE || FAKE_THREADS || I_MACH_CTHREADS */
637 /* Given a shared RV, copy it's value to a private RV, also copying the
638 * object status of the referent.
639 * If the private side is already an appropriate RV->SV combination, keep
643 S_get_RV(pTHX_ SV *sv, SV *ssv) {
644 SV *sobj = SvRV(ssv);
647 ((obj = SvRV(sv))) &&
648 (Perl_sharedsv_find(aTHX_ obj) == sobj) &&
649 (SvTYPE(obj) == SvTYPE(sobj))))
651 /* Can't reuse obj */
653 SvREFCNT_dec(SvRV(sv));
655 assert(SvTYPE(sv) >= SVt_RV);
656 sv_setsv_nomg(sv, &PL_sv_undef);
659 obj = S_sharedsv_new_private(aTHX_ SvRV(ssv));
664 /* Remove any old blessing */
665 SvREFCNT_dec(SvSTASH(obj));
668 if (SvOBJECT(sobj)) {
669 /* Add any new old blessing */
671 char* stash_ptr = SvPV((SV*) SvSTASH(sobj), len);
672 HV* stash = gv_stashpvn(stash_ptr, len, TRUE);
674 SvSTASH_set(obj, (HV*)SvREFCNT_inc(stash));
679 /* ------------ PERL_MAGIC_shared_scalar(n) functions -------------- */
681 /* Get magic for PERL_MAGIC_shared_scalar(n) */
684 sharedsv_scalar_mg_get(pTHX_ SV *sv, MAGIC *mg)
686 SV *ssv = (SV *) mg->mg_ptr;
691 S_get_RV(aTHX_ sv, ssv);
693 sv_setsv_nomg(sv, ssv);
699 /* Copy the contents of a private SV to a shared SV.
700 * Used by various mg_set()-type functions.
701 * Assumes lock is held.
704 sharedsv_scalar_store(pTHX_ SV *sv, SV *ssv)
709 assert(PL_sharedsv_lock.owner == aTHX);
712 SV *sobj = Perl_sharedsv_find(aTHX_ obj);
715 SvUPGRADE(ssv, SVt_RV);
716 sv_setsv_nomg(ssv, &PL_sv_undef);
718 SvRV_set(ssv, SvREFCNT_inc(sobj));
720 if (SvOBJECT(sobj)) {
721 /* Remove any old blessing */
722 SvREFCNT_dec(SvSTASH(sobj));
726 SV* fake_stash = newSVpv(HvNAME_get(SvSTASH(obj)),0);
728 SvSTASH_set(sobj, (HV*)fake_stash);
737 sv_setsv_nomg(ssv, sv);
739 /* Remove any old blessing */
740 SvREFCNT_dec(SvSTASH(ssv));
744 SV* fake_stash = newSVpv(HvNAME_get(SvSTASH(sv)),0);
746 SvSTASH_set(ssv, (HV*)fake_stash);
751 Perl_croak(aTHX_ "Invalid value for shared scalar");
755 /* Set magic for PERL_MAGIC_shared_scalar(n) */
758 sharedsv_scalar_mg_set(pTHX_ SV *sv, MAGIC *mg)
760 SV *ssv = (SV*)(mg->mg_ptr);
763 if (SvTYPE(ssv) < SvTYPE(sv)) {
766 sv_upgrade(ssv, SvTYPE(sv));
769 sharedsv_scalar_store(aTHX_ sv, ssv);
774 /* Free magic for PERL_MAGIC_shared_scalar(n) */
777 sharedsv_scalar_mg_free(pTHX_ SV *sv, MAGIC *mg)
779 S_sharedsv_dec(aTHX_ (SV*)mg->mg_ptr);
784 * Called during cloning of PERL_MAGIC_shared_scalar(n) magic in new thread
787 sharedsv_scalar_mg_dup(pTHX_ MAGIC *mg, CLONE_PARAMS *param)
789 SvREFCNT_inc_void(mg->mg_ptr);
795 * Called during local $shared
798 sharedsv_scalar_mg_local(pTHX_ SV* nsv, MAGIC *mg)
801 SV *ssv = (SV *) mg->mg_ptr;
804 SvREFCNT_inc_void(ssv);
807 nmg = sv_magicext(nsv, mg->mg_obj, mg->mg_type, mg->mg_virtual,
808 mg->mg_ptr, mg->mg_len);
809 nmg->mg_flags = mg->mg_flags;
810 nmg->mg_private = mg->mg_private;
816 MGVTBL sharedsv_scalar_vtbl = {
817 sharedsv_scalar_mg_get, /* get */
818 sharedsv_scalar_mg_set, /* set */
821 sharedsv_scalar_mg_free, /* free */
823 sharedsv_scalar_mg_dup, /* dup */
825 sharedsv_scalar_mg_local, /* local */
829 /* ------------ PERL_MAGIC_tiedelem(p) functions -------------- */
831 /* Get magic for PERL_MAGIC_tiedelem(p) */
834 sharedsv_elem_mg_FETCH(pTHX_ SV *sv, MAGIC *mg)
837 SV *saggregate = S_sharedsv_from_obj(aTHX_ mg->mg_obj);
841 if (SvTYPE(saggregate) == SVt_PVAV) {
842 assert ( mg->mg_ptr == 0 );
844 svp = av_fetch((AV*) saggregate, mg->mg_len, 0);
846 char *key = mg->mg_ptr;
847 STRLEN len = mg->mg_len;
848 assert ( mg->mg_ptr != 0 );
849 if (mg->mg_len == HEf_SVKEY) {
850 key = SvPV((SV *) mg->mg_ptr, len);
853 svp = hv_fetch((HV*) saggregate, key, len, 0);
857 /* Exists in the array */
859 S_get_RV(aTHX_ sv, *svp);
861 /* XXX Can this branch ever happen? DAPM */
862 /* XXX assert("no such branch"); */
863 Perl_sharedsv_associate(aTHX_ sv, *svp);
867 /* Not in the array */
868 sv_setsv(sv, &PL_sv_undef);
874 /* Set magic for PERL_MAGIC_tiedelem(p) */
877 sharedsv_elem_mg_STORE(pTHX_ SV *sv, MAGIC *mg)
880 SV *saggregate = S_sharedsv_from_obj(aTHX_ mg->mg_obj);
882 /* Theory - SV itself is magically shared - and we have ordered the
883 magic such that by the time we get here it has been stored
884 to its shared counterpart
888 if (SvTYPE(saggregate) == SVt_PVAV) {
889 assert ( mg->mg_ptr == 0 );
891 svp = av_fetch((AV*) saggregate, mg->mg_len, 1);
893 char *key = mg->mg_ptr;
894 STRLEN len = mg->mg_len;
895 assert ( mg->mg_ptr != 0 );
896 if (mg->mg_len == HEf_SVKEY)
897 key = SvPV((SV *) mg->mg_ptr, len);
899 svp = hv_fetch((HV*) saggregate, key, len, 1);
902 Perl_sharedsv_associate(aTHX_ sv, *svp);
903 sharedsv_scalar_store(aTHX_ sv, *svp);
908 /* Clear magic for PERL_MAGIC_tiedelem(p) */
911 sharedsv_elem_mg_DELETE(pTHX_ SV *sv, MAGIC *mg)
915 SV *saggregate = S_sharedsv_from_obj(aTHX_ mg->mg_obj);
917 sharedsv_elem_mg_FETCH(aTHX_ sv, mg);
918 if ((shmg = mg_find(sv, PERL_MAGIC_shared_scalar)))
919 sharedsv_scalar_mg_get(aTHX_ sv, shmg);
920 if (SvTYPE(saggregate) == SVt_PVAV) {
922 av_delete((AV*) saggregate, mg->mg_len, G_DISCARD);
924 char *key = mg->mg_ptr;
925 STRLEN len = mg->mg_len;
926 assert ( mg->mg_ptr != 0 );
927 if (mg->mg_len == HEf_SVKEY)
928 key = SvPV((SV *) mg->mg_ptr, len);
930 hv_delete((HV*) saggregate, key, len, G_DISCARD);
937 /* Called during cloning of PERL_MAGIC_tiedelem(p) magic in new
941 sharedsv_elem_mg_dup(pTHX_ MAGIC *mg, CLONE_PARAMS *param)
943 SvREFCNT_inc_void(S_sharedsv_from_obj(aTHX_ mg->mg_obj));
944 assert(mg->mg_flags & MGf_DUP);
948 MGVTBL sharedsv_elem_vtbl = {
949 sharedsv_elem_mg_FETCH, /* get */
950 sharedsv_elem_mg_STORE, /* set */
952 sharedsv_elem_mg_DELETE, /* clear */
955 sharedsv_elem_mg_dup, /* dup */
961 /* ------------ PERL_MAGIC_tied(P) functions -------------- */
963 /* Len magic for PERL_MAGIC_tied(P) */
966 sharedsv_array_mg_FETCHSIZE(pTHX_ SV *sv, MAGIC *mg)
969 SV *ssv = (SV *) mg->mg_ptr;
972 if (SvTYPE(ssv) == SVt_PVAV) {
973 val = av_len((AV*) ssv);
975 /* Not actually defined by tie API but ... */
976 val = HvKEYS((HV*) ssv);
982 /* Clear magic for PERL_MAGIC_tied(P) */
985 sharedsv_array_mg_CLEAR(pTHX_ SV *sv, MAGIC *mg)
988 SV *ssv = (SV *) mg->mg_ptr;
990 if (SvTYPE(ssv) == SVt_PVAV) {
999 /* Free magic for PERL_MAGIC_tied(P) */
1002 sharedsv_array_mg_free(pTHX_ SV *sv, MAGIC *mg)
1004 S_sharedsv_dec(aTHX_ (SV*)mg->mg_ptr);
1009 * Copy magic for PERL_MAGIC_tied(P)
1010 * This is called when perl is about to access an element of
1014 sharedsv_array_mg_copy(pTHX_ SV *sv, MAGIC* mg,
1015 SV *nsv, const char *name, int namlen)
1017 MAGIC *nmg = sv_magicext(nsv,mg->mg_obj,
1018 toLOWER(mg->mg_type),&sharedsv_elem_vtbl,
1020 nmg->mg_flags |= MGf_DUP;
1024 /* Called during cloning of PERL_MAGIC_tied(P) magic in new thread */
1027 sharedsv_array_mg_dup(pTHX_ MAGIC *mg, CLONE_PARAMS *param)
1029 SvREFCNT_inc_void((SV*)mg->mg_ptr);
1030 assert(mg->mg_flags & MGf_DUP);
1034 MGVTBL sharedsv_array_vtbl = {
1037 sharedsv_array_mg_FETCHSIZE,/* len */
1038 sharedsv_array_mg_CLEAR, /* clear */
1039 sharedsv_array_mg_free, /* free */
1040 sharedsv_array_mg_copy, /* copy */
1041 sharedsv_array_mg_dup, /* dup */
1047 =for apidoc sharedsv_unlock
1049 Recursively unlocks a shared sv.
1054 Perl_sharedsv_unlock(pTHX_ SV *ssv)
1056 user_lock *ul = S_get_userlock(aTHX_ ssv, 0);
1058 recursive_lock_release(aTHX_ &ul->lock);
1061 =for apidoc sharedsv_lock
1063 Recursive locks on a sharedsv.
1064 Locks are dynamically scoped at the level of the first lock.
1069 Perl_sharedsv_lock(pTHX_ SV *ssv)
1074 ul = S_get_userlock(aTHX_ ssv, 1);
1075 recursive_lock_acquire(aTHX_ &ul->lock, __FILE__, __LINE__);
1078 /* Handles calls from lock() builtin via PL_lockhook */
1081 Perl_sharedsv_locksv(pTHX_ SV *sv)
1087 ssv = Perl_sharedsv_find(aTHX_ sv);
1089 croak("lock can only be used on shared values");
1090 Perl_sharedsv_lock(aTHX_ ssv);
1093 =head1 Shared SV Functions
1095 =for apidoc sharedsv_init
1097 Saves a space for keeping SVs wider than an interpreter.
1102 Perl_sharedsv_init(pTHX)
1105 /* This pair leaves us in shared context ... */
1106 PL_sharedsv_space = perl_alloc();
1107 perl_construct(PL_sharedsv_space);
1109 recursive_lock_init(aTHX_ &PL_sharedsv_lock);
1110 PL_lockhook = &Perl_sharedsv_locksv;
1111 PL_sharehook = &Perl_sharedsv_share;
1114 #endif /* USE_ITHREADS */
1116 MODULE = threads::shared PACKAGE = threads::shared::tie
1126 SV *sobj = S_sharedsv_from_obj(aTHX_ obj);
1128 for (i = 1; i < items; i++) {
1129 SV* tmp = newSVsv(ST(i));
1132 stmp = S_sharedsv_new_shared(aTHX_ tmp);
1133 sharedsv_scalar_store(aTHX_ tmp, stmp);
1135 av_push((AV*) sobj, stmp);
1136 SvREFCNT_inc_void(stmp);
1143 UNSHIFT(SV *obj, ...)
1146 SV *sobj = S_sharedsv_from_obj(aTHX_ obj);
1150 av_unshift((AV*)sobj, items - 1);
1152 for (i = 1; i < items; i++) {
1153 SV *tmp = newSVsv(ST(i));
1154 SV *stmp = S_sharedsv_new_shared(aTHX_ tmp);
1155 sharedsv_scalar_store(aTHX_ tmp, stmp);
1157 av_store((AV*) sobj, i - 1, stmp);
1158 SvREFCNT_inc_void(stmp);
1169 SV *sobj = S_sharedsv_from_obj(aTHX_ obj);
1173 ssv = av_pop((AV*)sobj);
1175 ST(0) = sv_newmortal();
1176 Perl_sharedsv_associate(aTHX_ ST(0), ssv);
1179 /* XSRETURN(1); - implied */
1186 SV *sobj = S_sharedsv_from_obj(aTHX_ obj);
1190 ssv = av_shift((AV*)sobj);
1192 ST(0) = sv_newmortal();
1193 Perl_sharedsv_associate(aTHX_ ST(0), ssv);
1196 /* XSRETURN(1); - implied */
1200 EXTEND(SV *obj, IV count)
1203 SV *sobj = S_sharedsv_from_obj(aTHX_ obj);
1205 av_extend((AV*)sobj, count);
1210 STORESIZE(SV *obj,IV count)
1213 SV *sobj = S_sharedsv_from_obj(aTHX_ obj);
1215 av_fill((AV*) sobj, count);
1220 EXISTS(SV *obj, SV *index)
1223 SV *sobj = S_sharedsv_from_obj(aTHX_ obj);
1225 if (SvTYPE(sobj) == SVt_PVAV) {
1227 exists = av_exists((AV*) sobj, SvIV(index));
1230 char *key = SvPV(index,len);
1232 exists = hv_exists((HV*) sobj, key, len);
1235 ST(0) = (exists) ? &PL_sv_yes : &PL_sv_no;
1236 /* XSRETURN(1); - implied */
1243 SV *sobj = S_sharedsv_from_obj(aTHX_ obj);
1249 hv_iterinit((HV*) sobj);
1250 entry = hv_iternext((HV*) sobj);
1252 key = hv_iterkey(entry,&len);
1254 ST(0) = sv_2mortal(newSVpv(key, len));
1257 ST(0) = &PL_sv_undef;
1260 /* XSRETURN(1); - implied */
1264 NEXTKEY(SV *obj, SV *oldkey)
1267 SV *sobj = S_sharedsv_from_obj(aTHX_ obj);
1273 entry = hv_iternext((HV*) sobj);
1275 key = hv_iterkey(entry,&len);
1277 ST(0) = sv_2mortal(newSVpv(key, len));
1280 ST(0) = &PL_sv_undef;
1283 /* XSRETURN(1); - implied */
1286 MODULE = threads::shared PACKAGE = threads::shared
1299 ssv = Perl_sharedsv_find(aTHX_ ref);
1302 ST(0) = sv_2mortal(newSVuv(PTR2UV(ssv)));
1303 /* XSRETURN(1); - implied */
1315 ssv = Perl_sharedsv_find(aTHX_ ref);
1317 Perl_warn(aTHX_ "%" SVf " is not shared", ST(0));
1320 ST(0) = sv_2mortal(newSViv(SvREFCNT(ssv)));
1321 /* XSRETURN(1); - implied */
1329 Perl_croak(aTHX_ "Argument to share needs to be passed as ref");
1333 Perl_sharedsv_share(aTHX_ ref);
1334 ST(0) = sv_2mortal(newRV_inc(ref));
1335 /* XSRETURN(1); - implied */
1339 cond_wait(SV *ref_cond, SV *ref_lock = 0)
1340 PROTOTYPE: \[$@%];\[$@%]
1343 perl_cond* user_condition;
1347 if (!SvROK(ref_cond))
1348 Perl_croak(aTHX_ "Argument to cond_wait needs to be passed as ref");
1349 ref_cond = SvRV(ref_cond);
1350 if (SvROK(ref_cond))
1351 ref_cond = SvRV(ref_cond);
1352 ssv = Perl_sharedsv_find(aTHX_ ref_cond);
1354 Perl_croak(aTHX_ "cond_wait can only be used on shared values");
1355 ul = S_get_userlock(aTHX_ ssv, 1);
1357 user_condition = &ul->user_cond;
1358 if (ref_lock && (ref_cond != ref_lock)) {
1359 if (!SvROK(ref_lock))
1360 Perl_croak(aTHX_ "cond_wait lock needs to be passed as ref");
1361 ref_lock = SvRV(ref_lock);
1362 if (SvROK(ref_lock)) ref_lock = SvRV(ref_lock);
1363 ssv = Perl_sharedsv_find(aTHX_ ref_lock);
1365 Perl_croak(aTHX_ "cond_wait lock must be a shared value");
1366 ul = S_get_userlock(aTHX_ ssv, 1);
1368 if (ul->lock.owner != aTHX)
1369 croak("You need a lock before you can cond_wait");
1370 /* Stealing the members of the lock object worries me - NI-S */
1371 MUTEX_LOCK(&ul->lock.mutex);
1372 ul->lock.owner = NULL;
1373 locks = ul->lock.locks;
1376 /* Since we are releasing the lock here we need to tell other
1377 * people that is ok to go ahead and use it */
1378 COND_SIGNAL(&ul->lock.cond);
1379 COND_WAIT(user_condition, &ul->lock.mutex);
1380 while(ul->lock.owner != NULL) {
1381 /* OK -- must reacquire the lock */
1382 COND_WAIT(&ul->lock.cond, &ul->lock.mutex);
1384 ul->lock.owner = aTHX;
1385 ul->lock.locks = locks;
1386 MUTEX_UNLOCK(&ul->lock.mutex);
1390 cond_timedwait(SV *ref_cond, double abs, SV *ref_lock = 0)
1391 PROTOTYPE: \[$@%]$;\[$@%]
1394 perl_cond* user_condition;
1398 if (! SvROK(ref_cond))
1399 Perl_croak(aTHX_ "Argument to cond_timedwait needs to be passed as ref");
1400 ref_cond = SvRV(ref_cond);
1401 if (SvROK(ref_cond))
1402 ref_cond = SvRV(ref_cond);
1403 ssv = Perl_sharedsv_find(aTHX_ ref_cond);
1405 Perl_croak(aTHX_ "cond_timedwait can only be used on shared values");
1406 ul = S_get_userlock(aTHX_ ssv, 1);
1408 user_condition = &ul->user_cond;
1409 if (ref_lock && (ref_cond != ref_lock)) {
1410 if (! SvROK(ref_lock))
1411 Perl_croak(aTHX_ "cond_timedwait lock needs to be passed as ref");
1412 ref_lock = SvRV(ref_lock);
1413 if (SvROK(ref_lock)) ref_lock = SvRV(ref_lock);
1414 ssv = Perl_sharedsv_find(aTHX_ ref_lock);
1416 Perl_croak(aTHX_ "cond_timedwait lock must be a shared value");
1417 ul = S_get_userlock(aTHX_ ssv, 1);
1419 if (ul->lock.owner != aTHX)
1420 Perl_croak(aTHX_ "You need a lock before you can cond_wait");
1422 MUTEX_LOCK(&ul->lock.mutex);
1423 ul->lock.owner = NULL;
1424 locks = ul->lock.locks;
1426 /* Since we are releasing the lock here we need to tell other
1427 * people that is ok to go ahead and use it */
1428 COND_SIGNAL(&ul->lock.cond);
1429 RETVAL = Perl_sharedsv_cond_timedwait(user_condition, &ul->lock.mutex, abs);
1430 while (ul->lock.owner != NULL) {
1431 /* OK -- must reacquire the lock... */
1432 COND_WAIT(&ul->lock.cond, &ul->lock.mutex);
1434 ul->lock.owner = aTHX;
1435 ul->lock.locks = locks;
1436 MUTEX_UNLOCK(&ul->lock.mutex);
1445 cond_signal(SV *ref)
1452 Perl_croak(aTHX_ "Argument to cond_signal needs to be passed as ref");
1456 ssv = Perl_sharedsv_find(aTHX_ ref);
1458 Perl_croak(aTHX_ "cond_signal can only be used on shared values");
1459 ul = S_get_userlock(aTHX_ ssv, 1);
1460 if (ckWARN(WARN_THREADS) && ul->lock.owner != aTHX) {
1461 Perl_warner(aTHX_ packWARN(WARN_THREADS),
1462 "cond_signal() called on unlocked variable");
1464 COND_SIGNAL(&ul->user_cond);
1468 cond_broadcast(SV *ref)
1475 Perl_croak(aTHX_ "Argument to cond_broadcast needs to be passed as ref");
1479 ssv = Perl_sharedsv_find(aTHX_ ref);
1481 Perl_croak(aTHX_ "cond_broadcast can only be used on shared values");
1482 ul = S_get_userlock(aTHX_ ssv, 1);
1483 if (ckWARN(WARN_THREADS) && ul->lock.owner != aTHX) {
1484 Perl_warner(aTHX_ packWARN(WARN_THREADS),
1485 "cond_broadcast() called on unlocked variable");
1487 COND_BROADCAST(&ul->user_cond);
1491 bless(SV* ref, ...);
1498 stash = CopSTASH(PL_curcop);
1500 SV* classname = ST(1);
1505 ! SvGMAGICAL(classname) &&
1506 ! SvAMAGIC(classname) &&
1509 Perl_croak(aTHX_ "Attempt to bless into a reference");
1511 ptr = SvPV(classname, len);
1512 if (ckWARN(WARN_MISC) && len == 0) {
1513 Perl_warner(aTHX_ packWARN(WARN_MISC),
1514 "Explicit blessing to '' (assuming package main)");
1516 stash = gv_stashpvn(ptr, len, TRUE);
1518 SvREFCNT_inc_void(ref);
1519 (void)sv_bless(ref, stash);
1520 ST(0) = sv_2mortal(ref);
1521 ssv = Perl_sharedsv_find(aTHX_ ref);
1527 SV* fake_stash = newSVpv(HvNAME_get(stash), 0);
1528 (void)sv_bless(ssv, (HV*)fake_stash);
1533 /* XSRETURN(1); - implied */
1535 #endif /* USE_ITHREADS */
1540 Perl_sharedsv_init(aTHX);
1541 #endif /* USE_ITHREADS */