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).
118 #define PERL_NO_GET_CONTEXT
123 # define NEED_vnewSVpvf
131 /* Magic signature(s) for mg_private to make PERL_MAGIC_ext magic safer */
132 #define UL_MAGIC_SIG 0x554C /* UL = user lock */
135 * The shared things need an intepreter to live in ...
137 PerlInterpreter *PL_sharedsv_space; /* The shared sv space */
138 /* To access shared space we fake aTHX in this scope and thread's context */
140 /* Bug #24255: We include ENTER+SAVETMPS/FREETMPS+LEAVE with
141 * SHARED_CONTEXT/CALLER_CONTEXT macros, so that any mortals, etc. created
142 * while in the shared interpreter context don't languish */
144 #define SHARED_CONTEXT \
146 PERL_SET_CONTEXT((aTHX = PL_sharedsv_space)); \
151 /* So we need a way to switch back to the caller's context... */
152 /* So we declare _another_ copy of the aTHX variable ... */
153 #define dTHXc PerlInterpreter *caller_perl = aTHX
155 /* ... and use it to switch back */
156 #define CALLER_CONTEXT \
160 PERL_SET_CONTEXT((aTHX = caller_perl)); \
164 * Only one thread at a time is allowed to mess with shared space.
169 PerlInterpreter *owner;
178 recursive_lock_t PL_sharedsv_lock; /* Mutex protecting the shared sv space */
181 recursive_lock_init(pTHX_ recursive_lock_t *lock)
183 Zero(lock,1,recursive_lock_t);
184 MUTEX_INIT(&lock->mutex);
185 COND_INIT(&lock->cond);
189 recursive_lock_destroy(pTHX_ recursive_lock_t *lock)
191 MUTEX_DESTROY(&lock->mutex);
192 COND_DESTROY(&lock->cond);
196 recursive_lock_release(pTHX_ recursive_lock_t *lock)
198 MUTEX_LOCK(&lock->mutex);
199 if (lock->owner == aTHX) {
200 if (--lock->locks == 0) {
202 COND_SIGNAL(&lock->cond);
205 MUTEX_UNLOCK(&lock->mutex);
209 recursive_lock_acquire(pTHX_ recursive_lock_t *lock, char *file, int line)
212 MUTEX_LOCK(&lock->mutex);
213 if (lock->owner == aTHX) {
216 while (lock->owner) {
218 Perl_warn(aTHX_ " %p waiting - owned by %p %s:%d\n",
219 aTHX, lock->owner, lock->file, lock->line);
221 COND_WAIT(&lock->cond,&lock->mutex);
230 MUTEX_UNLOCK(&lock->mutex);
231 SAVEDESTRUCTOR_X(recursive_lock_release,lock);
237 recursive_lock_acquire(aTHX_ &PL_sharedsv_lock, __FILE__, __LINE__);\
240 /* The unlocking is done automatically at scope exit */
241 #define LEAVE_LOCK LEAVE
244 /* A common idiom is to acquire access and switch in ... */
245 #define SHARED_EDIT \
251 /* ... then switch out and release access. */
252 #define SHARED_RELEASE \
260 This structure is attached (using ext magic) to any shared SV that
261 is used by user-level locking or condition code
265 recursive_lock_t lock; /* For user-levl locks */
266 perl_cond user_cond; /* For user-level conditions */
269 /* Magic used for attaching user_lock structs to shared SVs
271 The vtable used has just one entry - when the SV goes away
272 we free the memory for the above.
276 sharedsv_userlock_free(pTHX_ SV *sv, MAGIC *mg)
278 user_lock *ul = (user_lock *) mg->mg_ptr;
279 assert(aTHX == PL_sharedsv_space);
281 recursive_lock_destroy(aTHX_ &ul->lock);
282 COND_DESTROY(&ul->user_cond);
283 PerlMemShared_free(ul);
289 MGVTBL sharedsv_userlock_vtbl = {
294 sharedsv_userlock_free, /* free */
303 * Access to shared things is heavily based on MAGIC
304 * - in mg.h/mg.c/sv.c sense
307 /* In any thread that has access to a shared thing there is a "proxy"
308 for it in its own space which has 'MAGIC' associated which accesses
312 extern MGVTBL sharedsv_scalar_vtbl; /* Scalars have this vtable */
313 extern MGVTBL sharedsv_array_vtbl; /* Hashes and arrays have this
315 extern MGVTBL sharedsv_elem_vtbl; /* Elements of hashes and arrays have
316 this _AS WELL AS_ the scalar magic:
317 The sharedsv_elem_vtbl associates the element with the array/hash and
318 the sharedsv_scalar_vtbl associates it with the value
322 /* Get shared aggregate SV pointed to by threads::shared::tie magic object */
325 S_sharedsv_from_obj(pTHX_ SV *sv)
327 return ((SvROK(sv)) ? INT2PTR(SV *, SvIV(SvRV(sv))) : NULL);
331 /* Return the user_lock structure (if any) associated with a shared SV.
332 * If create is true, create one if it doesn't exist
335 S_get_userlock(pTHX_ SV* ssv, bool create)
338 user_lock *ul = NULL;
341 /* XXX Redesign the storage of user locks so we don't need a global
342 * lock to access them ???? DAPM */
345 /* Version of mg_find that also checks the private signature */
346 for (mg = SvMAGIC(ssv); mg; mg = mg->mg_moremagic) {
347 if ((mg->mg_type == PERL_MAGIC_ext) &&
348 (mg->mg_private == UL_MAGIC_SIG))
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 mg = sv_magicext(ssv, NULL, PERL_MAGIC_ext, &sharedsv_userlock_vtbl,
364 mg->mg_private = UL_MAGIC_SIG; /* Set private signature */
365 recursive_lock_init(aTHX_ &ul->lock);
366 COND_INIT(&ul->user_cond);
374 /* Given a private side SV tries to find if the SV has a shared backend,
375 * by looking for the magic.
378 Perl_sharedsv_find(pTHX_ SV *sv)
381 if (SvTYPE(sv) >= SVt_PVMG) {
385 if ((mg = mg_find(sv, PERL_MAGIC_tied))
386 && mg->mg_virtual == &sharedsv_array_vtbl) {
387 return ((SV *)mg->mg_ptr);
391 /* This should work for elements as well as they
392 * have scalar magic as well as their element magic
394 if ((mg = mg_find(sv, PERL_MAGIC_shared_scalar))
395 && mg->mg_virtual == &sharedsv_scalar_vtbl) {
396 return ((SV *)mg->mg_ptr);
401 /* Just for tidyness of API also handle tie objects */
402 if (SvROK(sv) && sv_derived_from(sv, "threads::shared::tie")) {
403 return (S_sharedsv_from_obj(aTHX_ sv));
409 /* Associate a private SV with a shared SV by pointing the appropriate
411 * Assumes lock is held.
414 Perl_sharedsv_associate(pTHX_ SV *sv, SV *ssv)
418 /* If we are asked for any private ops we need a thread */
419 assert ( aTHX != PL_sharedsv_space );
421 /* To avoid need for recursive locks require caller to hold lock */
422 assert ( PL_sharedsv_lock.owner == aTHX );
427 if (!(mg = mg_find(sv, PERL_MAGIC_tied))
428 || mg->mg_virtual != &sharedsv_array_vtbl
429 || (SV*) mg->mg_ptr != ssv)
432 sv_setref_iv(obj, "threads::shared::tie", PTR2IV(ssv));
434 sv_unmagic(sv, PERL_MAGIC_tied);
436 mg = sv_magicext(sv, obj, PERL_MAGIC_tied, &sharedsv_array_vtbl,
438 mg->mg_flags |= (MGf_COPY|MGf_DUP);
439 SvREFCNT_inc_void(ssv);
445 if ((SvTYPE(sv) < SVt_PVMG)
446 || !(mg = mg_find(sv, PERL_MAGIC_shared_scalar))
447 || mg->mg_virtual != &sharedsv_scalar_vtbl
448 || (SV*) mg->mg_ptr != ssv)
451 sv_unmagic(sv, PERL_MAGIC_shared_scalar);
453 mg = sv_magicext(sv, Nullsv, PERL_MAGIC_shared_scalar,
454 &sharedsv_scalar_vtbl, (char *)ssv, 0);
455 mg->mg_flags |= (MGf_DUP
460 SvREFCNT_inc_void(ssv);
465 assert ( Perl_sharedsv_find(aTHX_ sv) == ssv );
469 /* Given a private SV, create and return an associated shared SV.
470 * Assumes lock is held.
473 S_sharedsv_new_shared(pTHX_ SV *sv)
478 assert(PL_sharedsv_lock.owner == aTHX);
479 assert(aTHX != PL_sharedsv_space);
483 SvREFCNT(ssv) = 0; /* Will be upped to 1 by Perl_sharedsv_associate */
484 sv_upgrade(ssv, SvTYPE(sv));
486 Perl_sharedsv_associate(aTHX_ sv, ssv);
491 /* Given a shared SV, create and return an associated private SV.
492 * Assumes lock is held.
495 S_sharedsv_new_private(pTHX_ SV *ssv)
499 assert(PL_sharedsv_lock.owner == aTHX);
500 assert(aTHX != PL_sharedsv_space);
503 sv_upgrade(sv, SvTYPE(ssv));
504 Perl_sharedsv_associate(aTHX_ sv, ssv);
509 /* A threadsafe version of SvREFCNT_dec(ssv) */
512 S_sharedsv_dec(pTHX_ SV* ssv)
517 if (SvREFCNT(ssv) > 1) {
518 /* No side effects, so can do it lightweight */
530 /* Implements Perl-level share() and :shared */
533 Perl_sharedsv_share(pTHX_ SV *sv)
537 Perl_croak(aTHX_ "Cannot share globs yet");
541 Perl_croak(aTHX_ "Cannot share subs yet");
546 (void) S_sharedsv_new_shared(aTHX_ sv);
555 /* Number of milliseconds from 1/1/1601 to 1/1/1970 */
556 #define EPOCH_BIAS 11644473600000.
558 /* Returns relative time in milliseconds. (Adapted from Time::HiRes.) */
560 S_abs_2_rel_milli(double abs)
564 /* Get current time (in units of 100 nanoseconds since 1/1/1601) */
567 __int64 i64; /* 'signed' to keep compilers happy */
570 GetSystemTimeAsFileTime(&now.ft);
572 /* Relative time in milliseconds */
573 rel = (abs * 1000.) - (((double)now.i64 / 10000.) - EPOCH_BIAS);
582 # define ABS2RELMILLI(abs) \
584 abs -= (double)time(NULL); \
585 if (abs > 0) { abs *= 1000; } \
591 /* Do OS-specific condition timed wait */
594 Perl_sharedsv_cond_timedwait(perl_cond *cond, perl_mutex *mut, double abs)
596 #if defined(NETWARE) || defined(FAKE_THREADS) || defined(I_MACH_CTHREADS)
597 Perl_croak_nocontext("cond_timedwait not supported on this platform");
604 /* See comments in win32/win32thread.h COND_WAIT vis-a-vis race */
605 switch (WaitForSingleObject(cond->sem, S_abs_2_rel_milli(abs))) {
606 case WAIT_OBJECT_0: got_it = 1; break;
607 case WAIT_TIMEOUT: break;
609 /* WAIT_FAILED? WAIT_ABANDONED? others? */
610 Perl_croak_nocontext("panic: cond_timedwait (%ld)",GetLastError());
623 if ((rc = DosResetEventSem(*cond,&n_a)) && (rc != ERROR_ALREADY_RESET))
624 Perl_rc = rc, croak_with_os2error("panic: cond_timedwait-reset");
626 if (CheckOSError(DosWaitEventSem(*cond,abs))
627 && (rc != ERROR_INTERRUPT))
628 croak_with_os2error("panic: cond_timedwait");
629 if (rc == ERROR_INTERRUPT) errno = EINTR;
632 # else /* Hope you're I_PTHREAD! */
636 ts.tv_sec = (long)abs;
637 abs -= (NV)ts.tv_sec;
638 ts.tv_nsec = (long)(abs * 1000000000.0);
640 switch (pthread_cond_timedwait(cond, mut, &ts)) {
641 case 0: got_it = 1; break;
642 case ETIMEDOUT: break;
645 if (errno == ETIMEDOUT || errno == EAGAIN)
649 Perl_croak_nocontext("panic: cond_timedwait");
655 #endif /* NETWARE || FAKE_THREADS || I_MACH_CTHREADS */
659 /* Given a shared RV, copy it's value to a private RV, also copying the
660 * object status of the referent.
661 * If the private side is already an appropriate RV->SV combination, keep
665 S_get_RV(pTHX_ SV *sv, SV *ssv) {
666 SV *sobj = SvRV(ssv);
669 ((obj = SvRV(sv))) &&
670 (Perl_sharedsv_find(aTHX_ obj) == sobj) &&
671 (SvTYPE(obj) == SvTYPE(sobj))))
673 /* Can't reuse obj */
675 SvREFCNT_dec(SvRV(sv));
677 assert(SvTYPE(sv) >= SVt_RV);
678 sv_setsv_nomg(sv, &PL_sv_undef);
681 obj = S_sharedsv_new_private(aTHX_ SvRV(ssv));
686 /* Remove any old blessing */
687 SvREFCNT_dec(SvSTASH(obj));
690 if (SvOBJECT(sobj)) {
691 /* Add any new old blessing */
693 char* stash_ptr = SvPV((SV*) SvSTASH(sobj), len);
694 HV* stash = gv_stashpvn(stash_ptr, len, TRUE);
696 SvSTASH_set(obj, (HV*)SvREFCNT_inc(stash));
701 /* ------------ PERL_MAGIC_shared_scalar(n) functions -------------- */
703 /* Get magic for PERL_MAGIC_shared_scalar(n) */
706 sharedsv_scalar_mg_get(pTHX_ SV *sv, MAGIC *mg)
708 SV *ssv = (SV *) mg->mg_ptr;
713 S_get_RV(aTHX_ sv, ssv);
715 sv_setsv_nomg(sv, ssv);
721 /* Copy the contents of a private SV to a shared SV.
722 * Used by various mg_set()-type functions.
723 * Assumes lock is held.
726 sharedsv_scalar_store(pTHX_ SV *sv, SV *ssv)
731 assert(PL_sharedsv_lock.owner == aTHX);
734 SV *sobj = Perl_sharedsv_find(aTHX_ obj);
737 (void)SvUPGRADE(ssv, SVt_RV);
738 sv_setsv_nomg(ssv, &PL_sv_undef);
740 SvRV_set(ssv, SvREFCNT_inc(sobj));
742 if (SvOBJECT(sobj)) {
743 /* Remove any old blessing */
744 SvREFCNT_dec(SvSTASH(sobj));
748 SV* fake_stash = newSVpv(HvNAME_get(SvSTASH(obj)),0);
750 SvSTASH_set(sobj, (HV*)fake_stash);
759 sv_setsv_nomg(ssv, sv);
761 /* Remove any old blessing */
762 SvREFCNT_dec(SvSTASH(ssv));
766 SV* fake_stash = newSVpv(HvNAME_get(SvSTASH(sv)),0);
768 SvSTASH_set(ssv, (HV*)fake_stash);
773 Perl_croak(aTHX_ "Invalid value for shared scalar");
777 /* Set magic for PERL_MAGIC_shared_scalar(n) */
780 sharedsv_scalar_mg_set(pTHX_ SV *sv, MAGIC *mg)
782 SV *ssv = (SV*)(mg->mg_ptr);
785 if (SvTYPE(ssv) < SvTYPE(sv)) {
788 sv_upgrade(ssv, SvTYPE(sv));
791 sharedsv_scalar_store(aTHX_ sv, ssv);
796 /* Free magic for PERL_MAGIC_shared_scalar(n) */
799 sharedsv_scalar_mg_free(pTHX_ SV *sv, MAGIC *mg)
801 S_sharedsv_dec(aTHX_ (SV*)mg->mg_ptr);
806 * Called during cloning of PERL_MAGIC_shared_scalar(n) magic in new thread
809 sharedsv_scalar_mg_dup(pTHX_ MAGIC *mg, CLONE_PARAMS *param)
811 SvREFCNT_inc_void(mg->mg_ptr);
817 * Called during local $shared
820 sharedsv_scalar_mg_local(pTHX_ SV* nsv, MAGIC *mg)
823 SV *ssv = (SV *) mg->mg_ptr;
826 SvREFCNT_inc_void(ssv);
829 nmg = sv_magicext(nsv, mg->mg_obj, mg->mg_type, mg->mg_virtual,
830 mg->mg_ptr, mg->mg_len);
831 nmg->mg_flags = mg->mg_flags;
832 nmg->mg_private = mg->mg_private;
838 MGVTBL sharedsv_scalar_vtbl = {
839 sharedsv_scalar_mg_get, /* get */
840 sharedsv_scalar_mg_set, /* set */
843 sharedsv_scalar_mg_free, /* free */
845 sharedsv_scalar_mg_dup, /* dup */
847 sharedsv_scalar_mg_local, /* local */
851 /* ------------ PERL_MAGIC_tiedelem(p) functions -------------- */
853 /* Get magic for PERL_MAGIC_tiedelem(p) */
856 sharedsv_elem_mg_FETCH(pTHX_ SV *sv, MAGIC *mg)
859 SV *saggregate = S_sharedsv_from_obj(aTHX_ mg->mg_obj);
863 if (SvTYPE(saggregate) == SVt_PVAV) {
864 assert ( mg->mg_ptr == 0 );
866 svp = av_fetch((AV*) saggregate, mg->mg_len, 0);
868 char *key = mg->mg_ptr;
869 STRLEN len = mg->mg_len;
870 assert ( mg->mg_ptr != 0 );
871 if (mg->mg_len == HEf_SVKEY) {
872 key = SvPV((SV *) mg->mg_ptr, len);
875 svp = hv_fetch((HV*) saggregate, key, len, 0);
879 /* Exists in the array */
881 S_get_RV(aTHX_ sv, *svp);
883 /* XXX Can this branch ever happen? DAPM */
884 /* XXX assert("no such branch"); */
885 Perl_sharedsv_associate(aTHX_ sv, *svp);
889 /* Not in the array */
890 sv_setsv(sv, &PL_sv_undef);
896 /* Set magic for PERL_MAGIC_tiedelem(p) */
899 sharedsv_elem_mg_STORE(pTHX_ SV *sv, MAGIC *mg)
902 SV *saggregate = S_sharedsv_from_obj(aTHX_ mg->mg_obj);
904 /* Theory - SV itself is magically shared - and we have ordered the
905 magic such that by the time we get here it has been stored
906 to its shared counterpart
910 if (SvTYPE(saggregate) == SVt_PVAV) {
911 assert ( mg->mg_ptr == 0 );
913 svp = av_fetch((AV*) saggregate, mg->mg_len, 1);
915 char *key = mg->mg_ptr;
916 STRLEN len = mg->mg_len;
917 assert ( mg->mg_ptr != 0 );
918 if (mg->mg_len == HEf_SVKEY)
919 key = SvPV((SV *) mg->mg_ptr, len);
921 svp = hv_fetch((HV*) saggregate, key, len, 1);
924 Perl_sharedsv_associate(aTHX_ sv, *svp);
925 sharedsv_scalar_store(aTHX_ sv, *svp);
930 /* Clear magic for PERL_MAGIC_tiedelem(p) */
933 sharedsv_elem_mg_DELETE(pTHX_ SV *sv, MAGIC *mg)
937 SV *saggregate = S_sharedsv_from_obj(aTHX_ mg->mg_obj);
939 sharedsv_elem_mg_FETCH(aTHX_ sv, mg);
940 if ((shmg = mg_find(sv, PERL_MAGIC_shared_scalar)))
941 sharedsv_scalar_mg_get(aTHX_ sv, shmg);
942 if (SvTYPE(saggregate) == SVt_PVAV) {
944 av_delete((AV*) saggregate, mg->mg_len, G_DISCARD);
946 char *key = mg->mg_ptr;
947 STRLEN len = mg->mg_len;
948 assert ( mg->mg_ptr != 0 );
949 if (mg->mg_len == HEf_SVKEY)
950 key = SvPV((SV *) mg->mg_ptr, len);
952 hv_delete((HV*) saggregate, key, len, G_DISCARD);
959 /* Called during cloning of PERL_MAGIC_tiedelem(p) magic in new
963 sharedsv_elem_mg_dup(pTHX_ MAGIC *mg, CLONE_PARAMS *param)
965 SvREFCNT_inc_void(S_sharedsv_from_obj(aTHX_ mg->mg_obj));
966 assert(mg->mg_flags & MGf_DUP);
970 MGVTBL sharedsv_elem_vtbl = {
971 sharedsv_elem_mg_FETCH, /* get */
972 sharedsv_elem_mg_STORE, /* set */
974 sharedsv_elem_mg_DELETE, /* clear */
977 sharedsv_elem_mg_dup, /* dup */
983 /* ------------ PERL_MAGIC_tied(P) functions -------------- */
985 /* Len magic for PERL_MAGIC_tied(P) */
988 sharedsv_array_mg_FETCHSIZE(pTHX_ SV *sv, MAGIC *mg)
991 SV *ssv = (SV *) mg->mg_ptr;
994 if (SvTYPE(ssv) == SVt_PVAV) {
995 val = av_len((AV*) ssv);
997 /* Not actually defined by tie API but ... */
998 val = HvKEYS((HV*) ssv);
1004 /* Clear magic for PERL_MAGIC_tied(P) */
1007 sharedsv_array_mg_CLEAR(pTHX_ SV *sv, MAGIC *mg)
1010 SV *ssv = (SV *) mg->mg_ptr;
1012 if (SvTYPE(ssv) == SVt_PVAV) {
1013 av_clear((AV*) ssv);
1015 hv_clear((HV*) ssv);
1021 /* Free magic for PERL_MAGIC_tied(P) */
1024 sharedsv_array_mg_free(pTHX_ SV *sv, MAGIC *mg)
1026 S_sharedsv_dec(aTHX_ (SV*)mg->mg_ptr);
1031 * Copy magic for PERL_MAGIC_tied(P)
1032 * This is called when perl is about to access an element of
1036 sharedsv_array_mg_copy(pTHX_ SV *sv, MAGIC* mg,
1037 SV *nsv, const char *name, int namlen)
1039 MAGIC *nmg = sv_magicext(nsv,mg->mg_obj,
1040 toLOWER(mg->mg_type),&sharedsv_elem_vtbl,
1042 nmg->mg_flags |= MGf_DUP;
1046 /* Called during cloning of PERL_MAGIC_tied(P) magic in new thread */
1049 sharedsv_array_mg_dup(pTHX_ MAGIC *mg, CLONE_PARAMS *param)
1051 SvREFCNT_inc_void((SV*)mg->mg_ptr);
1052 assert(mg->mg_flags & MGf_DUP);
1056 MGVTBL sharedsv_array_vtbl = {
1059 sharedsv_array_mg_FETCHSIZE,/* len */
1060 sharedsv_array_mg_CLEAR, /* clear */
1061 sharedsv_array_mg_free, /* free */
1062 sharedsv_array_mg_copy, /* copy */
1063 sharedsv_array_mg_dup, /* dup */
1070 /* Recursively unlocks a shared sv. */
1073 Perl_sharedsv_unlock(pTHX_ SV *ssv)
1075 user_lock *ul = S_get_userlock(aTHX_ ssv, 0);
1077 recursive_lock_release(aTHX_ &ul->lock);
1081 /* Recursive locks on a sharedsv.
1082 * Locks are dynamically scoped at the level of the first lock.
1085 Perl_sharedsv_lock(pTHX_ SV *ssv)
1090 ul = S_get_userlock(aTHX_ ssv, 1);
1091 recursive_lock_acquire(aTHX_ &ul->lock, __FILE__, __LINE__);
1094 /* Handles calls from lock() builtin via PL_lockhook */
1097 Perl_sharedsv_locksv(pTHX_ SV *sv)
1103 ssv = Perl_sharedsv_find(aTHX_ sv);
1105 croak("lock can only be used on shared values");
1106 Perl_sharedsv_lock(aTHX_ ssv);
1110 /* Saves a space for keeping SVs wider than an interpreter. */
1113 Perl_sharedsv_init(pTHX)
1116 /* This pair leaves us in shared context ... */
1117 PL_sharedsv_space = perl_alloc();
1118 perl_construct(PL_sharedsv_space);
1120 recursive_lock_init(aTHX_ &PL_sharedsv_lock);
1121 PL_lockhook = &Perl_sharedsv_locksv;
1122 PL_sharehook = &Perl_sharedsv_share;
1125 #endif /* USE_ITHREADS */
1127 MODULE = threads::shared PACKAGE = threads::shared::tie
1137 SV *sobj = S_sharedsv_from_obj(aTHX_ obj);
1139 for (i = 1; i < items; i++) {
1140 SV* tmp = newSVsv(ST(i));
1143 stmp = S_sharedsv_new_shared(aTHX_ tmp);
1144 sharedsv_scalar_store(aTHX_ tmp, stmp);
1146 av_push((AV*) sobj, stmp);
1147 SvREFCNT_inc_void(stmp);
1154 UNSHIFT(SV *obj, ...)
1157 SV *sobj = S_sharedsv_from_obj(aTHX_ obj);
1161 av_unshift((AV*)sobj, items - 1);
1163 for (i = 1; i < items; i++) {
1164 SV *tmp = newSVsv(ST(i));
1165 SV *stmp = S_sharedsv_new_shared(aTHX_ tmp);
1166 sharedsv_scalar_store(aTHX_ tmp, stmp);
1168 av_store((AV*) sobj, i - 1, stmp);
1169 SvREFCNT_inc_void(stmp);
1180 SV *sobj = S_sharedsv_from_obj(aTHX_ obj);
1184 ssv = av_pop((AV*)sobj);
1186 ST(0) = sv_newmortal();
1187 Perl_sharedsv_associate(aTHX_ ST(0), ssv);
1190 /* XSRETURN(1); - implied */
1197 SV *sobj = S_sharedsv_from_obj(aTHX_ obj);
1201 ssv = av_shift((AV*)sobj);
1203 ST(0) = sv_newmortal();
1204 Perl_sharedsv_associate(aTHX_ ST(0), ssv);
1207 /* XSRETURN(1); - implied */
1211 EXTEND(SV *obj, IV count)
1214 SV *sobj = S_sharedsv_from_obj(aTHX_ obj);
1216 av_extend((AV*)sobj, count);
1221 STORESIZE(SV *obj,IV count)
1224 SV *sobj = S_sharedsv_from_obj(aTHX_ obj);
1226 av_fill((AV*) sobj, count);
1231 EXISTS(SV *obj, SV *index)
1234 SV *sobj = S_sharedsv_from_obj(aTHX_ obj);
1236 if (SvTYPE(sobj) == SVt_PVAV) {
1238 exists = av_exists((AV*) sobj, SvIV(index));
1241 char *key = SvPV(index,len);
1243 exists = hv_exists((HV*) sobj, key, len);
1246 ST(0) = (exists) ? &PL_sv_yes : &PL_sv_no;
1247 /* XSRETURN(1); - implied */
1254 SV *sobj = S_sharedsv_from_obj(aTHX_ obj);
1260 hv_iterinit((HV*) sobj);
1261 entry = hv_iternext((HV*) sobj);
1263 key = hv_iterkey(entry,&len);
1265 ST(0) = sv_2mortal(newSVpv(key, len));
1268 ST(0) = &PL_sv_undef;
1271 /* XSRETURN(1); - implied */
1275 NEXTKEY(SV *obj, SV *oldkey)
1278 SV *sobj = S_sharedsv_from_obj(aTHX_ obj);
1283 PERL_UNUSED_VAR(oldkey);
1287 entry = hv_iternext((HV*) sobj);
1289 key = hv_iterkey(entry,&len);
1291 ST(0) = sv_2mortal(newSVpv(key, len));
1294 ST(0) = &PL_sv_undef;
1297 /* XSRETURN(1); - implied */
1300 MODULE = threads::shared PACKAGE = threads::shared
1313 ssv = Perl_sharedsv_find(aTHX_ ref);
1316 ST(0) = sv_2mortal(newSVuv(PTR2UV(ssv)));
1317 /* XSRETURN(1); - implied */
1329 ssv = Perl_sharedsv_find(aTHX_ ref);
1331 if (ckWARN(WARN_THREADS)) {
1332 Perl_warner(aTHX_ packWARN(WARN_THREADS),
1333 "%" SVf " is not shared", ST(0));
1337 ST(0) = sv_2mortal(newSViv(SvREFCNT(ssv)));
1338 /* XSRETURN(1); - implied */
1346 Perl_croak(aTHX_ "Argument to share needs to be passed as ref");
1350 Perl_sharedsv_share(aTHX_ ref);
1351 ST(0) = sv_2mortal(newRV_inc(ref));
1352 /* XSRETURN(1); - implied */
1356 cond_wait(SV *ref_cond, SV *ref_lock = 0)
1357 PROTOTYPE: \[$@%];\[$@%]
1360 perl_cond* user_condition;
1364 if (!SvROK(ref_cond))
1365 Perl_croak(aTHX_ "Argument to cond_wait needs to be passed as ref");
1366 ref_cond = SvRV(ref_cond);
1367 if (SvROK(ref_cond))
1368 ref_cond = SvRV(ref_cond);
1369 ssv = Perl_sharedsv_find(aTHX_ ref_cond);
1371 Perl_croak(aTHX_ "cond_wait can only be used on shared values");
1372 ul = S_get_userlock(aTHX_ ssv, 1);
1374 user_condition = &ul->user_cond;
1375 if (ref_lock && (ref_cond != ref_lock)) {
1376 if (!SvROK(ref_lock))
1377 Perl_croak(aTHX_ "cond_wait lock needs to be passed as ref");
1378 ref_lock = SvRV(ref_lock);
1379 if (SvROK(ref_lock)) ref_lock = SvRV(ref_lock);
1380 ssv = Perl_sharedsv_find(aTHX_ ref_lock);
1382 Perl_croak(aTHX_ "cond_wait lock must be a shared value");
1383 ul = S_get_userlock(aTHX_ ssv, 1);
1385 if (ul->lock.owner != aTHX)
1386 croak("You need a lock before you can cond_wait");
1388 /* Stealing the members of the lock object worries me - NI-S */
1389 MUTEX_LOCK(&ul->lock.mutex);
1390 ul->lock.owner = NULL;
1391 locks = ul->lock.locks;
1394 /* Since we are releasing the lock here, we need to tell other
1395 * people that it is ok to go ahead and use it */
1396 COND_SIGNAL(&ul->lock.cond);
1397 COND_WAIT(user_condition, &ul->lock.mutex);
1398 while (ul->lock.owner != NULL) {
1399 /* OK -- must reacquire the lock */
1400 COND_WAIT(&ul->lock.cond, &ul->lock.mutex);
1402 ul->lock.owner = aTHX;
1403 ul->lock.locks = locks;
1404 MUTEX_UNLOCK(&ul->lock.mutex);
1408 cond_timedwait(SV *ref_cond, double abs, SV *ref_lock = 0)
1409 PROTOTYPE: \[$@%]$;\[$@%]
1412 perl_cond* user_condition;
1416 if (! SvROK(ref_cond))
1417 Perl_croak(aTHX_ "Argument to cond_timedwait needs to be passed as ref");
1418 ref_cond = SvRV(ref_cond);
1419 if (SvROK(ref_cond))
1420 ref_cond = SvRV(ref_cond);
1421 ssv = Perl_sharedsv_find(aTHX_ ref_cond);
1423 Perl_croak(aTHX_ "cond_timedwait can only be used on shared values");
1424 ul = S_get_userlock(aTHX_ ssv, 1);
1426 user_condition = &ul->user_cond;
1427 if (ref_lock && (ref_cond != ref_lock)) {
1428 if (! SvROK(ref_lock))
1429 Perl_croak(aTHX_ "cond_timedwait lock needs to be passed as ref");
1430 ref_lock = SvRV(ref_lock);
1431 if (SvROK(ref_lock)) ref_lock = SvRV(ref_lock);
1432 ssv = Perl_sharedsv_find(aTHX_ ref_lock);
1434 Perl_croak(aTHX_ "cond_timedwait lock must be a shared value");
1435 ul = S_get_userlock(aTHX_ ssv, 1);
1437 if (ul->lock.owner != aTHX)
1438 Perl_croak(aTHX_ "You need a lock before you can cond_wait");
1440 MUTEX_LOCK(&ul->lock.mutex);
1441 ul->lock.owner = NULL;
1442 locks = ul->lock.locks;
1444 /* Since we are releasing the lock here, we need to tell other
1445 * people that it is ok to go ahead and use it */
1446 COND_SIGNAL(&ul->lock.cond);
1447 RETVAL = Perl_sharedsv_cond_timedwait(user_condition, &ul->lock.mutex, abs);
1448 while (ul->lock.owner != NULL) {
1449 /* OK -- must reacquire the lock... */
1450 COND_WAIT(&ul->lock.cond, &ul->lock.mutex);
1452 ul->lock.owner = aTHX;
1453 ul->lock.locks = locks;
1454 MUTEX_UNLOCK(&ul->lock.mutex);
1463 cond_signal(SV *ref)
1470 Perl_croak(aTHX_ "Argument to cond_signal needs to be passed as ref");
1474 ssv = Perl_sharedsv_find(aTHX_ ref);
1476 Perl_croak(aTHX_ "cond_signal can only be used on shared values");
1477 ul = S_get_userlock(aTHX_ ssv, 1);
1478 if (ckWARN(WARN_THREADS) && ul->lock.owner != aTHX) {
1479 Perl_warner(aTHX_ packWARN(WARN_THREADS),
1480 "cond_signal() called on unlocked variable");
1482 COND_SIGNAL(&ul->user_cond);
1486 cond_broadcast(SV *ref)
1493 Perl_croak(aTHX_ "Argument to cond_broadcast needs to be passed as ref");
1497 ssv = Perl_sharedsv_find(aTHX_ ref);
1499 Perl_croak(aTHX_ "cond_broadcast can only be used on shared values");
1500 ul = S_get_userlock(aTHX_ ssv, 1);
1501 if (ckWARN(WARN_THREADS) && ul->lock.owner != aTHX) {
1502 Perl_warner(aTHX_ packWARN(WARN_THREADS),
1503 "cond_broadcast() called on unlocked variable");
1505 COND_BROADCAST(&ul->user_cond);
1509 bless(SV* ref, ...);
1516 stash = CopSTASH(PL_curcop);
1518 SV* classname = ST(1);
1523 ! SvGMAGICAL(classname) &&
1524 ! SvAMAGIC(classname) &&
1527 Perl_croak(aTHX_ "Attempt to bless into a reference");
1529 ptr = SvPV(classname, len);
1530 if (ckWARN(WARN_MISC) && len == 0) {
1531 Perl_warner(aTHX_ packWARN(WARN_MISC),
1532 "Explicit blessing to '' (assuming package main)");
1534 stash = gv_stashpvn(ptr, len, TRUE);
1536 SvREFCNT_inc_void(ref);
1537 (void)sv_bless(ref, stash);
1538 ST(0) = sv_2mortal(ref);
1539 ssv = Perl_sharedsv_find(aTHX_ ref);
1545 SV* fake_stash = newSVpv(HvNAME_get(stash), 0);
1546 (void)sv_bless(ssv, (HV*)fake_stash);
1551 /* XSRETURN(1); - implied */
1553 #endif /* USE_ITHREADS */
1558 Perl_sharedsv_init(aTHX);
1559 #endif /* USE_ITHREADS */