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_sv_2pv_flags
124 # define NEED_vnewSVpvf
126 # define NEED_newSVpvn_flags
133 /* Magic signature(s) for mg_private to make PERL_MAGIC_ext magic safer */
134 #define UL_MAGIC_SIG 0x554C /* UL = user lock */
137 * The shared things need an intepreter to live in ...
139 PerlInterpreter *PL_sharedsv_space; /* The shared sv space */
140 /* To access shared space we fake aTHX in this scope and thread's context */
142 /* Bug #24255: We include ENTER+SAVETMPS/FREETMPS+LEAVE with
143 * SHARED_CONTEXT/CALLER_CONTEXT macros, so that any mortals, etc. created
144 * while in the shared interpreter context don't languish */
146 #define SHARED_CONTEXT \
148 PERL_SET_CONTEXT((aTHX = PL_sharedsv_space)); \
153 /* So we need a way to switch back to the caller's context... */
154 /* So we declare _another_ copy of the aTHX variable ... */
155 #define dTHXc PerlInterpreter *caller_perl = aTHX
157 /* ... and use it to switch back */
158 #define CALLER_CONTEXT \
162 PERL_SET_CONTEXT((aTHX = caller_perl)); \
166 * Only one thread at a time is allowed to mess with shared space.
171 PerlInterpreter *owner;
180 recursive_lock_t PL_sharedsv_lock; /* Mutex protecting the shared sv space */
183 recursive_lock_init(pTHX_ recursive_lock_t *lock)
185 Zero(lock,1,recursive_lock_t);
186 MUTEX_INIT(&lock->mutex);
187 COND_INIT(&lock->cond);
191 recursive_lock_destroy(pTHX_ recursive_lock_t *lock)
193 MUTEX_DESTROY(&lock->mutex);
194 COND_DESTROY(&lock->cond);
198 recursive_lock_release(pTHX_ recursive_lock_t *lock)
200 MUTEX_LOCK(&lock->mutex);
201 if (lock->owner == aTHX) {
202 if (--lock->locks == 0) {
204 COND_SIGNAL(&lock->cond);
207 MUTEX_UNLOCK(&lock->mutex);
211 recursive_lock_acquire(pTHX_ recursive_lock_t *lock, char *file, int line)
214 MUTEX_LOCK(&lock->mutex);
215 if (lock->owner == aTHX) {
218 while (lock->owner) {
220 Perl_warn(aTHX_ " %p waiting - owned by %p %s:%d\n",
221 aTHX, lock->owner, lock->file, lock->line);
223 COND_WAIT(&lock->cond,&lock->mutex);
232 MUTEX_UNLOCK(&lock->mutex);
233 SAVEDESTRUCTOR_X(recursive_lock_release,lock);
239 recursive_lock_acquire(aTHX_ &PL_sharedsv_lock, __FILE__, __LINE__);\
242 /* The unlocking is done automatically at scope exit */
243 #define LEAVE_LOCK LEAVE
246 /* A common idiom is to acquire access and switch in ... */
247 #define SHARED_EDIT \
253 /* ... then switch out and release access. */
254 #define SHARED_RELEASE \
262 This structure is attached (using ext magic) to any shared SV that
263 is used by user-level locking or condition code
267 recursive_lock_t lock; /* For user-levl locks */
268 perl_cond user_cond; /* For user-level conditions */
271 /* Magic used for attaching user_lock structs to shared SVs
273 The vtable used has just one entry - when the SV goes away
274 we free the memory for the above.
278 sharedsv_userlock_free(pTHX_ SV *sv, MAGIC *mg)
280 user_lock *ul = (user_lock *) mg->mg_ptr;
281 assert(aTHX == PL_sharedsv_space);
283 recursive_lock_destroy(aTHX_ &ul->lock);
284 COND_DESTROY(&ul->user_cond);
285 PerlMemShared_free(ul);
291 MGVTBL sharedsv_userlock_vtbl = {
296 sharedsv_userlock_free, /* free */
305 * Access to shared things is heavily based on MAGIC
306 * - in mg.h/mg.c/sv.c sense
309 /* In any thread that has access to a shared thing there is a "proxy"
310 for it in its own space which has 'MAGIC' associated which accesses
314 extern MGVTBL sharedsv_scalar_vtbl; /* Scalars have this vtable */
315 extern MGVTBL sharedsv_array_vtbl; /* Hashes and arrays have this
317 extern MGVTBL sharedsv_elem_vtbl; /* Elements of hashes and arrays have
318 this _AS WELL AS_ the scalar magic:
319 The sharedsv_elem_vtbl associates the element with the array/hash and
320 the sharedsv_scalar_vtbl associates it with the value
324 /* Get shared aggregate SV pointed to by threads::shared::tie magic object */
327 S_sharedsv_from_obj(pTHX_ SV *sv)
329 return ((SvROK(sv)) ? INT2PTR(SV *, SvIV(SvRV(sv))) : NULL);
333 /* Return the user_lock structure (if any) associated with a shared SV.
334 * If create is true, create one if it doesn't exist
337 S_get_userlock(pTHX_ SV* ssv, bool create)
340 user_lock *ul = NULL;
343 /* XXX Redesign the storage of user locks so we don't need a global
344 * lock to access them ???? DAPM */
347 /* Version of mg_find that also checks the private signature */
348 for (mg = SvMAGIC(ssv); mg; mg = mg->mg_moremagic) {
349 if ((mg->mg_type == PERL_MAGIC_ext) &&
350 (mg->mg_private == UL_MAGIC_SIG))
357 ul = (user_lock*)(mg->mg_ptr);
361 ul = (user_lock *) PerlMemShared_malloc(sizeof(user_lock));
362 Zero(ul, 1, user_lock);
363 /* Attach to shared SV using ext magic */
364 mg = sv_magicext(ssv, NULL, PERL_MAGIC_ext, &sharedsv_userlock_vtbl,
366 mg->mg_private = UL_MAGIC_SIG; /* Set private signature */
367 recursive_lock_init(aTHX_ &ul->lock);
368 COND_INIT(&ul->user_cond);
376 /* Given a private side SV tries to find if the SV has a shared backend,
377 * by looking for the magic.
380 Perl_sharedsv_find(pTHX_ SV *sv)
383 if (SvTYPE(sv) >= SVt_PVMG) {
387 if ((mg = mg_find(sv, PERL_MAGIC_tied))
388 && mg->mg_virtual == &sharedsv_array_vtbl) {
389 return ((SV *)mg->mg_ptr);
393 /* This should work for elements as well as they
394 * have scalar magic as well as their element magic
396 if ((mg = mg_find(sv, PERL_MAGIC_shared_scalar))
397 && mg->mg_virtual == &sharedsv_scalar_vtbl) {
398 return ((SV *)mg->mg_ptr);
403 /* Just for tidyness of API also handle tie objects */
404 if (SvROK(sv) && sv_derived_from(sv, "threads::shared::tie")) {
405 return (S_sharedsv_from_obj(aTHX_ sv));
411 /* Associate a private SV with a shared SV by pointing the appropriate
413 * Assumes lock is held.
416 Perl_sharedsv_associate(pTHX_ SV *sv, SV *ssv)
420 /* If we are asked for any private ops we need a thread */
421 assert ( aTHX != PL_sharedsv_space );
423 /* To avoid need for recursive locks require caller to hold lock */
424 assert ( PL_sharedsv_lock.owner == aTHX );
429 if (!(mg = mg_find(sv, PERL_MAGIC_tied))
430 || mg->mg_virtual != &sharedsv_array_vtbl
431 || (SV*) mg->mg_ptr != ssv)
434 sv_setref_iv(obj, "threads::shared::tie", PTR2IV(ssv));
436 sv_unmagic(sv, PERL_MAGIC_tied);
438 mg = sv_magicext(sv, obj, PERL_MAGIC_tied, &sharedsv_array_vtbl,
440 mg->mg_flags |= (MGf_COPY|MGf_DUP);
441 SvREFCNT_inc_void(ssv);
447 if ((SvTYPE(sv) < SVt_PVMG)
448 || !(mg = mg_find(sv, PERL_MAGIC_shared_scalar))
449 || mg->mg_virtual != &sharedsv_scalar_vtbl
450 || (SV*) mg->mg_ptr != ssv)
453 sv_unmagic(sv, PERL_MAGIC_shared_scalar);
455 mg = sv_magicext(sv, Nullsv, PERL_MAGIC_shared_scalar,
456 &sharedsv_scalar_vtbl, (char *)ssv, 0);
457 mg->mg_flags |= (MGf_DUP
462 SvREFCNT_inc_void(ssv);
467 assert ( Perl_sharedsv_find(aTHX_ sv) == ssv );
471 /* Given a private SV, create and return an associated shared SV.
472 * Assumes lock is held.
475 S_sharedsv_new_shared(pTHX_ SV *sv)
480 assert(PL_sharedsv_lock.owner == aTHX);
481 assert(aTHX != PL_sharedsv_space);
485 SvREFCNT(ssv) = 0; /* Will be upped to 1 by Perl_sharedsv_associate */
486 sv_upgrade(ssv, SvTYPE(sv));
488 Perl_sharedsv_associate(aTHX_ sv, ssv);
493 /* Given a shared SV, create and return an associated private SV.
494 * Assumes lock is held.
497 S_sharedsv_new_private(pTHX_ SV *ssv)
501 assert(PL_sharedsv_lock.owner == aTHX);
502 assert(aTHX != PL_sharedsv_space);
505 sv_upgrade(sv, SvTYPE(ssv));
506 Perl_sharedsv_associate(aTHX_ sv, ssv);
511 /* A threadsafe version of SvREFCNT_dec(ssv) */
514 S_sharedsv_dec(pTHX_ SV* ssv)
519 if (SvREFCNT(ssv) > 1) {
520 /* No side effects, so can do it lightweight */
532 /* Implements Perl-level share() and :shared */
535 Perl_sharedsv_share(pTHX_ SV *sv)
539 Perl_croak(aTHX_ "Cannot share globs yet");
543 Perl_croak(aTHX_ "Cannot share subs yet");
548 (void) S_sharedsv_new_shared(aTHX_ sv);
557 /* Number of milliseconds from 1/1/1601 to 1/1/1970 */
558 #define EPOCH_BIAS 11644473600000.
560 /* Returns relative time in milliseconds. (Adapted from Time::HiRes.) */
562 S_abs_2_rel_milli(double abs)
566 /* Get current time (in units of 100 nanoseconds since 1/1/1601) */
569 __int64 i64; /* 'signed' to keep compilers happy */
572 GetSystemTimeAsFileTime(&now.ft);
574 /* Relative time in milliseconds */
575 rel = (abs * 1000.) - (((double)now.i64 / 10000.) - EPOCH_BIAS);
584 # define ABS2RELMILLI(abs) \
586 abs -= (double)time(NULL); \
587 if (abs > 0) { abs *= 1000; } \
593 /* Do OS-specific condition timed wait */
596 Perl_sharedsv_cond_timedwait(perl_cond *cond, perl_mutex *mut, double abs)
598 #if defined(NETWARE) || defined(FAKE_THREADS) || defined(I_MACH_CTHREADS)
599 Perl_croak_nocontext("cond_timedwait not supported on this platform");
606 /* See comments in win32/win32thread.h COND_WAIT vis-a-vis race */
607 switch (WaitForSingleObject(cond->sem, S_abs_2_rel_milli(abs))) {
608 case WAIT_OBJECT_0: got_it = 1; break;
609 case WAIT_TIMEOUT: break;
611 /* WAIT_FAILED? WAIT_ABANDONED? others? */
612 Perl_croak_nocontext("panic: cond_timedwait (%ld)",GetLastError());
625 if ((rc = DosResetEventSem(*cond,&n_a)) && (rc != ERROR_ALREADY_RESET))
626 Perl_rc = rc, croak_with_os2error("panic: cond_timedwait-reset");
628 if (CheckOSError(DosWaitEventSem(*cond,abs))
629 && (rc != ERROR_INTERRUPT))
630 croak_with_os2error("panic: cond_timedwait");
631 if (rc == ERROR_INTERRUPT) errno = EINTR;
634 # else /* Hope you're I_PTHREAD! */
638 ts.tv_sec = (long)abs;
639 abs -= (NV)ts.tv_sec;
640 ts.tv_nsec = (long)(abs * 1000000000.0);
642 switch (pthread_cond_timedwait(cond, mut, &ts)) {
643 case 0: got_it = 1; break;
644 case ETIMEDOUT: break;
647 if (errno == ETIMEDOUT || errno == EAGAIN)
651 Perl_croak_nocontext("panic: cond_timedwait");
657 #endif /* NETWARE || FAKE_THREADS || I_MACH_CTHREADS */
661 /* Given a shared RV, copy it's value to a private RV, also copying the
662 * object status of the referent.
663 * If the private side is already an appropriate RV->SV combination, keep
667 S_get_RV(pTHX_ SV *sv, SV *ssv) {
668 SV *sobj = SvRV(ssv);
671 ((obj = SvRV(sv))) &&
672 (Perl_sharedsv_find(aTHX_ obj) == sobj) &&
673 (SvTYPE(obj) == SvTYPE(sobj))))
675 /* Can't reuse obj */
677 SvREFCNT_dec(SvRV(sv));
679 assert(SvTYPE(sv) >= SVt_RV);
680 sv_setsv_nomg(sv, &PL_sv_undef);
683 obj = S_sharedsv_new_private(aTHX_ SvRV(ssv));
688 /* Remove any old blessing */
689 SvREFCNT_dec(SvSTASH(obj));
692 if (SvOBJECT(sobj)) {
693 /* Add any new old blessing */
695 char* stash_ptr = SvPV((SV*) SvSTASH(sobj), len);
696 HV* stash = gv_stashpvn(stash_ptr, len, TRUE);
698 SvSTASH_set(obj, (HV*)SvREFCNT_inc(stash));
703 /* ------------ PERL_MAGIC_shared_scalar(n) functions -------------- */
705 /* Get magic for PERL_MAGIC_shared_scalar(n) */
708 sharedsv_scalar_mg_get(pTHX_ SV *sv, MAGIC *mg)
710 SV *ssv = (SV *) mg->mg_ptr;
715 S_get_RV(aTHX_ sv, ssv);
716 /* Look ahead for refs of refs */
717 if (SvROK(SvRV(ssv))) {
719 S_get_RV(aTHX_ SvRV(sv), SvRV(ssv));
722 sv_setsv_nomg(sv, ssv);
728 /* Copy the contents of a private SV to a shared SV.
729 * Used by various mg_set()-type functions.
730 * Assumes lock is held.
733 sharedsv_scalar_store(pTHX_ SV *sv, SV *ssv)
738 assert(PL_sharedsv_lock.owner == aTHX);
741 SV *sobj = Perl_sharedsv_find(aTHX_ obj);
744 (void)SvUPGRADE(ssv, SVt_RV);
745 sv_setsv_nomg(ssv, &PL_sv_undef);
747 SvRV_set(ssv, SvREFCNT_inc(sobj));
749 if (SvOBJECT(sobj)) {
750 /* Remove any old blessing */
751 SvREFCNT_dec(SvSTASH(sobj));
755 SV* fake_stash = newSVpv(HvNAME_get(SvSTASH(obj)),0);
757 SvSTASH_set(sobj, (HV*)fake_stash);
766 sv_setsv_nomg(ssv, sv);
768 /* Remove any old blessing */
769 SvREFCNT_dec(SvSTASH(ssv));
773 SV* fake_stash = newSVpv(HvNAME_get(SvSTASH(sv)),0);
775 SvSTASH_set(ssv, (HV*)fake_stash);
780 Perl_croak(aTHX_ "Invalid value for shared scalar");
784 /* Set magic for PERL_MAGIC_shared_scalar(n) */
787 sharedsv_scalar_mg_set(pTHX_ SV *sv, MAGIC *mg)
789 SV *ssv = (SV*)(mg->mg_ptr);
792 if (SvTYPE(ssv) < SvTYPE(sv)) {
795 sv_upgrade(ssv, SvTYPE(sv));
798 sharedsv_scalar_store(aTHX_ sv, ssv);
803 /* Free magic for PERL_MAGIC_shared_scalar(n) */
806 sharedsv_scalar_mg_free(pTHX_ SV *sv, MAGIC *mg)
808 S_sharedsv_dec(aTHX_ (SV*)mg->mg_ptr);
813 * Called during cloning of PERL_MAGIC_shared_scalar(n) magic in new thread
816 sharedsv_scalar_mg_dup(pTHX_ MAGIC *mg, CLONE_PARAMS *param)
818 SvREFCNT_inc_void(mg->mg_ptr);
824 * Called during local $shared
827 sharedsv_scalar_mg_local(pTHX_ SV* nsv, MAGIC *mg)
830 SV *ssv = (SV *) mg->mg_ptr;
833 SvREFCNT_inc_void(ssv);
836 nmg = sv_magicext(nsv, mg->mg_obj, mg->mg_type, mg->mg_virtual,
837 mg->mg_ptr, mg->mg_len);
838 nmg->mg_flags = mg->mg_flags;
839 nmg->mg_private = mg->mg_private;
845 MGVTBL sharedsv_scalar_vtbl = {
846 sharedsv_scalar_mg_get, /* get */
847 sharedsv_scalar_mg_set, /* set */
850 sharedsv_scalar_mg_free, /* free */
852 sharedsv_scalar_mg_dup, /* dup */
854 sharedsv_scalar_mg_local, /* local */
858 /* ------------ PERL_MAGIC_tiedelem(p) functions -------------- */
860 /* Get magic for PERL_MAGIC_tiedelem(p) */
863 sharedsv_elem_mg_FETCH(pTHX_ SV *sv, MAGIC *mg)
866 SV *saggregate = S_sharedsv_from_obj(aTHX_ mg->mg_obj);
870 if (SvTYPE(saggregate) == SVt_PVAV) {
871 assert ( mg->mg_ptr == 0 );
873 svp = av_fetch((AV*) saggregate, mg->mg_len, 0);
875 char *key = mg->mg_ptr;
876 I32 len = mg->mg_len;
877 assert ( mg->mg_ptr != 0 );
878 if (mg->mg_len == HEf_SVKEY) {
879 key = SvPV((SV *)mg->mg_ptr, len);
880 if (SvUTF8((SV *)mg->mg_ptr)) {
885 svp = hv_fetch((HV*) saggregate, key, len, 0);
889 /* Exists in the array */
891 S_get_RV(aTHX_ sv, *svp);
892 /* Look ahead for refs of refs */
893 if (SvROK(SvRV(*svp))) {
895 S_get_RV(aTHX_ SvRV(sv), SvRV(*svp));
898 /* $ary->[elem] or $ary->{elem} is a scalar */
899 Perl_sharedsv_associate(aTHX_ sv, *svp);
903 /* Not in the array */
904 sv_setsv(sv, &PL_sv_undef);
910 /* Set magic for PERL_MAGIC_tiedelem(p) */
913 sharedsv_elem_mg_STORE(pTHX_ SV *sv, MAGIC *mg)
916 SV *saggregate = S_sharedsv_from_obj(aTHX_ mg->mg_obj);
918 /* Theory - SV itself is magically shared - and we have ordered the
919 magic such that by the time we get here it has been stored
920 to its shared counterpart
924 if (SvTYPE(saggregate) == SVt_PVAV) {
925 assert ( mg->mg_ptr == 0 );
927 svp = av_fetch((AV*) saggregate, mg->mg_len, 1);
929 char *key = mg->mg_ptr;
930 I32 len = mg->mg_len;
931 assert ( mg->mg_ptr != 0 );
932 if (mg->mg_len == HEf_SVKEY) {
933 key = SvPV((SV *)mg->mg_ptr, len);
934 if (SvUTF8((SV *)mg->mg_ptr)) {
939 svp = hv_fetch((HV*) saggregate, key, len, 1);
942 Perl_sharedsv_associate(aTHX_ sv, *svp);
943 sharedsv_scalar_store(aTHX_ sv, *svp);
948 /* Clear magic for PERL_MAGIC_tiedelem(p) */
951 sharedsv_elem_mg_DELETE(pTHX_ SV *sv, MAGIC *mg)
955 SV *saggregate = S_sharedsv_from_obj(aTHX_ mg->mg_obj);
957 sharedsv_elem_mg_FETCH(aTHX_ sv, mg);
958 if ((shmg = mg_find(sv, PERL_MAGIC_shared_scalar)))
959 sharedsv_scalar_mg_get(aTHX_ sv, shmg);
960 if (SvTYPE(saggregate) == SVt_PVAV) {
962 av_delete((AV*) saggregate, mg->mg_len, G_DISCARD);
964 char *key = mg->mg_ptr;
965 I32 len = mg->mg_len;
966 assert ( mg->mg_ptr != 0 );
967 if (mg->mg_len == HEf_SVKEY) {
968 key = SvPV((SV *)mg->mg_ptr, len);
969 if (SvUTF8((SV *)mg->mg_ptr)) {
974 hv_delete((HV*) saggregate, key, len, G_DISCARD);
981 /* Called during cloning of PERL_MAGIC_tiedelem(p) magic in new
985 sharedsv_elem_mg_dup(pTHX_ MAGIC *mg, CLONE_PARAMS *param)
987 SvREFCNT_inc_void(S_sharedsv_from_obj(aTHX_ mg->mg_obj));
988 assert(mg->mg_flags & MGf_DUP);
992 MGVTBL sharedsv_elem_vtbl = {
993 sharedsv_elem_mg_FETCH, /* get */
994 sharedsv_elem_mg_STORE, /* set */
996 sharedsv_elem_mg_DELETE, /* clear */
999 sharedsv_elem_mg_dup, /* dup */
1005 /* ------------ PERL_MAGIC_tied(P) functions -------------- */
1007 /* Len magic for PERL_MAGIC_tied(P) */
1010 sharedsv_array_mg_FETCHSIZE(pTHX_ SV *sv, MAGIC *mg)
1013 SV *ssv = (SV *) mg->mg_ptr;
1016 if (SvTYPE(ssv) == SVt_PVAV) {
1017 val = av_len((AV*) ssv);
1019 /* Not actually defined by tie API but ... */
1020 val = HvKEYS((HV*) ssv);
1026 /* Clear magic for PERL_MAGIC_tied(P) */
1029 sharedsv_array_mg_CLEAR(pTHX_ SV *sv, MAGIC *mg)
1032 SV *ssv = (SV *) mg->mg_ptr;
1034 if (SvTYPE(ssv) == SVt_PVAV) {
1035 av_clear((AV*) ssv);
1037 hv_clear((HV*) ssv);
1043 /* Free magic for PERL_MAGIC_tied(P) */
1046 sharedsv_array_mg_free(pTHX_ SV *sv, MAGIC *mg)
1048 S_sharedsv_dec(aTHX_ (SV*)mg->mg_ptr);
1053 * Copy magic for PERL_MAGIC_tied(P)
1054 * This is called when perl is about to access an element of
1057 #if PERL_VERSION >= 11
1059 sharedsv_array_mg_copy(pTHX_ SV *sv, MAGIC* mg,
1060 SV *nsv, const char *name, I32 namlen)
1063 sharedsv_array_mg_copy(pTHX_ SV *sv, MAGIC* mg,
1064 SV *nsv, const char *name, int namlen)
1067 MAGIC *nmg = sv_magicext(nsv,mg->mg_obj,
1068 toLOWER(mg->mg_type),&sharedsv_elem_vtbl,
1070 nmg->mg_flags |= MGf_DUP;
1074 /* Called during cloning of PERL_MAGIC_tied(P) magic in new thread */
1077 sharedsv_array_mg_dup(pTHX_ MAGIC *mg, CLONE_PARAMS *param)
1079 SvREFCNT_inc_void((SV*)mg->mg_ptr);
1080 assert(mg->mg_flags & MGf_DUP);
1084 MGVTBL sharedsv_array_vtbl = {
1087 sharedsv_array_mg_FETCHSIZE,/* len */
1088 sharedsv_array_mg_CLEAR, /* clear */
1089 sharedsv_array_mg_free, /* free */
1090 sharedsv_array_mg_copy, /* copy */
1091 sharedsv_array_mg_dup, /* dup */
1098 /* Recursively unlocks a shared sv. */
1101 Perl_sharedsv_unlock(pTHX_ SV *ssv)
1103 user_lock *ul = S_get_userlock(aTHX_ ssv, 0);
1105 recursive_lock_release(aTHX_ &ul->lock);
1109 /* Recursive locks on a sharedsv.
1110 * Locks are dynamically scoped at the level of the first lock.
1113 Perl_sharedsv_lock(pTHX_ SV *ssv)
1118 ul = S_get_userlock(aTHX_ ssv, 1);
1119 recursive_lock_acquire(aTHX_ &ul->lock, __FILE__, __LINE__);
1122 /* Handles calls from lock() builtin via PL_lockhook */
1125 Perl_sharedsv_locksv(pTHX_ SV *sv)
1131 ssv = Perl_sharedsv_find(aTHX_ sv);
1133 croak("lock can only be used on shared values");
1134 Perl_sharedsv_lock(aTHX_ ssv);
1138 /* Can a shared object be destroyed?
1139 * True if not a shared,
1140 * or if detroying last proxy on a shared object
1142 #ifdef PL_destroyhook
1144 Perl_shared_object_destroy(pTHX_ SV *sv)
1150 ssv = Perl_sharedsv_find(aTHX_ sv);
1151 return (!ssv || (SvREFCNT(ssv) <= 1));
1156 /* Saves a space for keeping SVs wider than an interpreter. */
1159 Perl_sharedsv_init(pTHX)
1162 /* This pair leaves us in shared context ... */
1163 PL_sharedsv_space = perl_alloc();
1164 perl_construct(PL_sharedsv_space);
1166 recursive_lock_init(aTHX_ &PL_sharedsv_lock);
1167 PL_lockhook = &Perl_sharedsv_locksv;
1168 PL_sharehook = &Perl_sharedsv_share;
1169 #ifdef PL_destroyhook
1170 PL_destroyhook = &Perl_shared_object_destroy;
1174 #endif /* USE_ITHREADS */
1176 MODULE = threads::shared PACKAGE = threads::shared::tie
1186 SV *sobj = S_sharedsv_from_obj(aTHX_ obj);
1188 for (i = 1; i < items; i++) {
1189 SV* tmp = newSVsv(ST(i));
1192 stmp = S_sharedsv_new_shared(aTHX_ tmp);
1193 sharedsv_scalar_store(aTHX_ tmp, stmp);
1195 av_push((AV*) sobj, stmp);
1196 SvREFCNT_inc_void(stmp);
1203 UNSHIFT(SV *obj, ...)
1206 SV *sobj = S_sharedsv_from_obj(aTHX_ obj);
1210 av_unshift((AV*)sobj, items - 1);
1212 for (i = 1; i < items; i++) {
1213 SV *tmp = newSVsv(ST(i));
1214 SV *stmp = S_sharedsv_new_shared(aTHX_ tmp);
1215 sharedsv_scalar_store(aTHX_ tmp, stmp);
1217 av_store((AV*) sobj, i - 1, stmp);
1218 SvREFCNT_inc_void(stmp);
1229 SV *sobj = S_sharedsv_from_obj(aTHX_ obj);
1233 ssv = av_pop((AV*)sobj);
1235 ST(0) = sv_newmortal();
1236 Perl_sharedsv_associate(aTHX_ ST(0), ssv);
1239 /* XSRETURN(1); - implied */
1246 SV *sobj = S_sharedsv_from_obj(aTHX_ obj);
1250 ssv = av_shift((AV*)sobj);
1252 ST(0) = sv_newmortal();
1253 Perl_sharedsv_associate(aTHX_ ST(0), ssv);
1256 /* XSRETURN(1); - implied */
1260 EXTEND(SV *obj, IV count)
1263 SV *sobj = S_sharedsv_from_obj(aTHX_ obj);
1265 av_extend((AV*)sobj, count);
1270 STORESIZE(SV *obj,IV count)
1273 SV *sobj = S_sharedsv_from_obj(aTHX_ obj);
1275 av_fill((AV*) sobj, count);
1280 EXISTS(SV *obj, SV *index)
1283 SV *sobj = S_sharedsv_from_obj(aTHX_ obj);
1285 if (SvTYPE(sobj) == SVt_PVAV) {
1287 exists = av_exists((AV*) sobj, SvIV(index));
1290 char *key = SvPVutf8(index, len);
1291 if (SvUTF8(index)) {
1295 exists = hv_exists((HV*) sobj, key, len);
1298 ST(0) = (exists) ? &PL_sv_yes : &PL_sv_no;
1299 /* XSRETURN(1); - implied */
1306 SV *sobj = S_sharedsv_from_obj(aTHX_ obj);
1312 hv_iterinit((HV*) sobj);
1313 entry = hv_iternext((HV*) sobj);
1315 I32 utf8 = HeKUTF8(entry);
1316 key = hv_iterkey(entry,&len);
1318 ST(0) = sv_2mortal(newSVpvn_utf8(key, len, utf8));
1321 ST(0) = &PL_sv_undef;
1324 /* XSRETURN(1); - implied */
1328 NEXTKEY(SV *obj, SV *oldkey)
1331 SV *sobj = S_sharedsv_from_obj(aTHX_ obj);
1336 PERL_UNUSED_VAR(oldkey);
1340 entry = hv_iternext((HV*) sobj);
1342 I32 utf8 = HeKUTF8(entry);
1343 key = hv_iterkey(entry,&len);
1345 ST(0) = sv_2mortal(newSVpvn_utf8(key, len, utf8));
1348 ST(0) = &PL_sv_undef;
1351 /* XSRETURN(1); - implied */
1354 MODULE = threads::shared PACKAGE = threads::shared
1364 myref = SvRV(myref);
1365 if (SvMAGICAL(myref))
1368 myref = SvRV(myref);
1369 ssv = Perl_sharedsv_find(aTHX_ myref);
1372 ST(0) = sv_2mortal(newSVuv(PTR2UV(ssv)));
1373 /* XSRETURN(1); - implied */
1382 myref = SvRV(myref);
1384 myref = SvRV(myref);
1385 ssv = Perl_sharedsv_find(aTHX_ myref);
1387 if (ckWARN(WARN_THREADS)) {
1388 Perl_warner(aTHX_ packWARN(WARN_THREADS),
1389 "%" SVf " is not shared", ST(0));
1393 ST(0) = sv_2mortal(newSViv(SvREFCNT(ssv)));
1394 /* XSRETURN(1); - implied */
1402 Perl_croak(aTHX_ "Argument to share needs to be passed as ref");
1403 myref = SvRV(myref);
1405 myref = SvRV(myref);
1406 Perl_sharedsv_share(aTHX_ myref);
1407 ST(0) = sv_2mortal(newRV_inc(myref));
1408 /* XSRETURN(1); - implied */
1412 cond_wait(SV *ref_cond, SV *ref_lock = 0)
1413 PROTOTYPE: \[$@%];\[$@%]
1416 perl_cond* user_condition;
1420 if (!SvROK(ref_cond))
1421 Perl_croak(aTHX_ "Argument to cond_wait needs to be passed as ref");
1422 ref_cond = SvRV(ref_cond);
1423 if (SvROK(ref_cond))
1424 ref_cond = SvRV(ref_cond);
1425 ssv = Perl_sharedsv_find(aTHX_ ref_cond);
1427 Perl_croak(aTHX_ "cond_wait can only be used on shared values");
1428 ul = S_get_userlock(aTHX_ ssv, 1);
1430 user_condition = &ul->user_cond;
1431 if (ref_lock && (ref_cond != ref_lock)) {
1432 if (!SvROK(ref_lock))
1433 Perl_croak(aTHX_ "cond_wait lock needs to be passed as ref");
1434 ref_lock = SvRV(ref_lock);
1435 if (SvROK(ref_lock)) ref_lock = SvRV(ref_lock);
1436 ssv = Perl_sharedsv_find(aTHX_ ref_lock);
1438 Perl_croak(aTHX_ "cond_wait lock must be a shared value");
1439 ul = S_get_userlock(aTHX_ ssv, 1);
1441 if (ul->lock.owner != aTHX)
1442 croak("You need a lock before you can cond_wait");
1444 /* Stealing the members of the lock object worries me - NI-S */
1445 MUTEX_LOCK(&ul->lock.mutex);
1446 ul->lock.owner = NULL;
1447 locks = ul->lock.locks;
1450 /* Since we are releasing the lock here, we need to tell other
1451 * people that it is ok to go ahead and use it */
1452 COND_SIGNAL(&ul->lock.cond);
1453 COND_WAIT(user_condition, &ul->lock.mutex);
1454 while (ul->lock.owner != NULL) {
1455 /* OK -- must reacquire the lock */
1456 COND_WAIT(&ul->lock.cond, &ul->lock.mutex);
1458 ul->lock.owner = aTHX;
1459 ul->lock.locks = locks;
1460 MUTEX_UNLOCK(&ul->lock.mutex);
1464 cond_timedwait(SV *ref_cond, double abs, SV *ref_lock = 0)
1465 PROTOTYPE: \[$@%]$;\[$@%]
1468 perl_cond* user_condition;
1472 if (! SvROK(ref_cond))
1473 Perl_croak(aTHX_ "Argument to cond_timedwait needs to be passed as ref");
1474 ref_cond = SvRV(ref_cond);
1475 if (SvROK(ref_cond))
1476 ref_cond = SvRV(ref_cond);
1477 ssv = Perl_sharedsv_find(aTHX_ ref_cond);
1479 Perl_croak(aTHX_ "cond_timedwait can only be used on shared values");
1480 ul = S_get_userlock(aTHX_ ssv, 1);
1482 user_condition = &ul->user_cond;
1483 if (ref_lock && (ref_cond != ref_lock)) {
1484 if (! SvROK(ref_lock))
1485 Perl_croak(aTHX_ "cond_timedwait lock needs to be passed as ref");
1486 ref_lock = SvRV(ref_lock);
1487 if (SvROK(ref_lock)) ref_lock = SvRV(ref_lock);
1488 ssv = Perl_sharedsv_find(aTHX_ ref_lock);
1490 Perl_croak(aTHX_ "cond_timedwait lock must be a shared value");
1491 ul = S_get_userlock(aTHX_ ssv, 1);
1493 if (ul->lock.owner != aTHX)
1494 Perl_croak(aTHX_ "You need a lock before you can cond_wait");
1496 MUTEX_LOCK(&ul->lock.mutex);
1497 ul->lock.owner = NULL;
1498 locks = ul->lock.locks;
1500 /* Since we are releasing the lock here, we need to tell other
1501 * people that it is ok to go ahead and use it */
1502 COND_SIGNAL(&ul->lock.cond);
1503 RETVAL = Perl_sharedsv_cond_timedwait(user_condition, &ul->lock.mutex, abs);
1504 while (ul->lock.owner != NULL) {
1505 /* OK -- must reacquire the lock... */
1506 COND_WAIT(&ul->lock.cond, &ul->lock.mutex);
1508 ul->lock.owner = aTHX;
1509 ul->lock.locks = locks;
1510 MUTEX_UNLOCK(&ul->lock.mutex);
1519 cond_signal(SV *myref)
1526 Perl_croak(aTHX_ "Argument to cond_signal needs to be passed as ref");
1527 myref = SvRV(myref);
1529 myref = SvRV(myref);
1530 ssv = Perl_sharedsv_find(aTHX_ myref);
1532 Perl_croak(aTHX_ "cond_signal can only be used on shared values");
1533 ul = S_get_userlock(aTHX_ ssv, 1);
1534 if (ckWARN(WARN_THREADS) && ul->lock.owner != aTHX) {
1535 Perl_warner(aTHX_ packWARN(WARN_THREADS),
1536 "cond_signal() called on unlocked variable");
1538 COND_SIGNAL(&ul->user_cond);
1542 cond_broadcast(SV *myref)
1549 Perl_croak(aTHX_ "Argument to cond_broadcast needs to be passed as ref");
1550 myref = SvRV(myref);
1552 myref = SvRV(myref);
1553 ssv = Perl_sharedsv_find(aTHX_ myref);
1555 Perl_croak(aTHX_ "cond_broadcast can only be used on shared values");
1556 ul = S_get_userlock(aTHX_ ssv, 1);
1557 if (ckWARN(WARN_THREADS) && ul->lock.owner != aTHX) {
1558 Perl_warner(aTHX_ packWARN(WARN_THREADS),
1559 "cond_broadcast() called on unlocked variable");
1561 COND_BROADCAST(&ul->user_cond);
1565 bless(SV* myref, ...);
1572 stash = CopSTASH(PL_curcop);
1574 SV* classname = ST(1);
1579 ! SvGMAGICAL(classname) &&
1580 ! SvAMAGIC(classname) &&
1583 Perl_croak(aTHX_ "Attempt to bless into a reference");
1585 ptr = SvPV(classname, len);
1586 if (ckWARN(WARN_MISC) && len == 0) {
1587 Perl_warner(aTHX_ packWARN(WARN_MISC),
1588 "Explicit blessing to '' (assuming package main)");
1590 stash = gv_stashpvn(ptr, len, TRUE);
1592 SvREFCNT_inc_void(myref);
1593 (void)sv_bless(myref, stash);
1594 ST(0) = sv_2mortal(myref);
1595 ssv = Perl_sharedsv_find(aTHX_ myref);
1601 SV* fake_stash = newSVpv(HvNAME_get(stash), 0);
1602 (void)sv_bless(ssv, (HV*)fake_stash);
1607 /* XSRETURN(1); - implied */
1609 #endif /* USE_ITHREADS */
1614 Perl_sharedsv_init(aTHX);
1615 #endif /* USE_ITHREADS */