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
132 /* Magic signature(s) for mg_private to make PERL_MAGIC_ext magic safer */
133 #define UL_MAGIC_SIG 0x554C /* UL = user lock */
136 * The shared things need an intepreter to live in ...
138 PerlInterpreter *PL_sharedsv_space; /* The shared sv space */
139 /* To access shared space we fake aTHX in this scope and thread's context */
141 /* Bug #24255: We include ENTER+SAVETMPS/FREETMPS+LEAVE with
142 * SHARED_CONTEXT/CALLER_CONTEXT macros, so that any mortals, etc. created
143 * while in the shared interpreter context don't languish */
145 #define SHARED_CONTEXT \
147 PERL_SET_CONTEXT((aTHX = PL_sharedsv_space)); \
152 /* So we need a way to switch back to the caller's context... */
153 /* So we declare _another_ copy of the aTHX variable ... */
154 #define dTHXc PerlInterpreter *caller_perl = aTHX
156 /* ... and use it to switch back */
157 #define CALLER_CONTEXT \
161 PERL_SET_CONTEXT((aTHX = caller_perl)); \
165 * Only one thread at a time is allowed to mess with shared space.
170 PerlInterpreter *owner;
179 recursive_lock_t PL_sharedsv_lock; /* Mutex protecting the shared sv space */
182 recursive_lock_init(pTHX_ recursive_lock_t *lock)
184 Zero(lock,1,recursive_lock_t);
185 MUTEX_INIT(&lock->mutex);
186 COND_INIT(&lock->cond);
190 recursive_lock_destroy(pTHX_ recursive_lock_t *lock)
192 MUTEX_DESTROY(&lock->mutex);
193 COND_DESTROY(&lock->cond);
197 recursive_lock_release(pTHX_ recursive_lock_t *lock)
199 MUTEX_LOCK(&lock->mutex);
200 if (lock->owner == aTHX) {
201 if (--lock->locks == 0) {
203 COND_SIGNAL(&lock->cond);
206 MUTEX_UNLOCK(&lock->mutex);
210 recursive_lock_acquire(pTHX_ recursive_lock_t *lock, char *file, int line)
213 MUTEX_LOCK(&lock->mutex);
214 if (lock->owner == aTHX) {
217 while (lock->owner) {
219 Perl_warn(aTHX_ " %p waiting - owned by %p %s:%d\n",
220 aTHX, lock->owner, lock->file, lock->line);
222 COND_WAIT(&lock->cond,&lock->mutex);
231 MUTEX_UNLOCK(&lock->mutex);
232 SAVEDESTRUCTOR_X(recursive_lock_release,lock);
238 recursive_lock_acquire(aTHX_ &PL_sharedsv_lock, __FILE__, __LINE__);\
241 /* The unlocking is done automatically at scope exit */
242 #define LEAVE_LOCK LEAVE
245 /* A common idiom is to acquire access and switch in ... */
246 #define SHARED_EDIT \
252 /* ... then switch out and release access. */
253 #define SHARED_RELEASE \
261 This structure is attached (using ext magic) to any shared SV that
262 is used by user-level locking or condition code
266 recursive_lock_t lock; /* For user-levl locks */
267 perl_cond user_cond; /* For user-level conditions */
270 /* Magic used for attaching user_lock structs to shared SVs
272 The vtable used has just one entry - when the SV goes away
273 we free the memory for the above.
277 sharedsv_userlock_free(pTHX_ SV *sv, MAGIC *mg)
279 user_lock *ul = (user_lock *) mg->mg_ptr;
280 assert(aTHX == PL_sharedsv_space);
282 recursive_lock_destroy(aTHX_ &ul->lock);
283 COND_DESTROY(&ul->user_cond);
284 PerlMemShared_free(ul);
290 MGVTBL sharedsv_userlock_vtbl = {
295 sharedsv_userlock_free, /* free */
304 * Access to shared things is heavily based on MAGIC
305 * - in mg.h/mg.c/sv.c sense
308 /* In any thread that has access to a shared thing there is a "proxy"
309 for it in its own space which has 'MAGIC' associated which accesses
313 extern MGVTBL sharedsv_scalar_vtbl; /* Scalars have this vtable */
314 extern MGVTBL sharedsv_array_vtbl; /* Hashes and arrays have this
316 extern MGVTBL sharedsv_elem_vtbl; /* Elements of hashes and arrays have
317 this _AS WELL AS_ the scalar magic:
318 The sharedsv_elem_vtbl associates the element with the array/hash and
319 the sharedsv_scalar_vtbl associates it with the value
323 /* Get shared aggregate SV pointed to by threads::shared::tie magic object */
326 S_sharedsv_from_obj(pTHX_ SV *sv)
328 return ((SvROK(sv)) ? INT2PTR(SV *, SvIV(SvRV(sv))) : NULL);
332 /* Return the user_lock structure (if any) associated with a shared SV.
333 * If create is true, create one if it doesn't exist
336 S_get_userlock(pTHX_ SV* ssv, bool create)
339 user_lock *ul = NULL;
342 /* XXX Redesign the storage of user locks so we don't need a global
343 * lock to access them ???? DAPM */
346 /* Version of mg_find that also checks the private signature */
347 for (mg = SvMAGIC(ssv); mg; mg = mg->mg_moremagic) {
348 if ((mg->mg_type == PERL_MAGIC_ext) &&
349 (mg->mg_private == UL_MAGIC_SIG))
356 ul = (user_lock*)(mg->mg_ptr);
360 ul = (user_lock *) PerlMemShared_malloc(sizeof(user_lock));
361 Zero(ul, 1, user_lock);
362 /* Attach to shared SV using ext magic */
363 mg = sv_magicext(ssv, NULL, PERL_MAGIC_ext, &sharedsv_userlock_vtbl,
365 mg->mg_private = UL_MAGIC_SIG; /* Set private signature */
366 recursive_lock_init(aTHX_ &ul->lock);
367 COND_INIT(&ul->user_cond);
375 /* Given a private side SV tries to find if the SV has a shared backend,
376 * by looking for the magic.
379 Perl_sharedsv_find(pTHX_ SV *sv)
382 if (SvTYPE(sv) >= SVt_PVMG) {
386 if ((mg = mg_find(sv, PERL_MAGIC_tied))
387 && mg->mg_virtual == &sharedsv_array_vtbl) {
388 return ((SV *)mg->mg_ptr);
392 /* This should work for elements as well as they
393 * have scalar magic as well as their element magic
395 if ((mg = mg_find(sv, PERL_MAGIC_shared_scalar))
396 && mg->mg_virtual == &sharedsv_scalar_vtbl) {
397 return ((SV *)mg->mg_ptr);
402 /* Just for tidyness of API also handle tie objects */
403 if (SvROK(sv) && sv_derived_from(sv, "threads::shared::tie")) {
404 return (S_sharedsv_from_obj(aTHX_ sv));
410 /* Associate a private SV with a shared SV by pointing the appropriate
412 * Assumes lock is held.
415 Perl_sharedsv_associate(pTHX_ SV *sv, SV *ssv)
419 /* If we are asked for any private ops we need a thread */
420 assert ( aTHX != PL_sharedsv_space );
422 /* To avoid need for recursive locks require caller to hold lock */
423 assert ( PL_sharedsv_lock.owner == aTHX );
428 if (!(mg = mg_find(sv, PERL_MAGIC_tied))
429 || mg->mg_virtual != &sharedsv_array_vtbl
430 || (SV*) mg->mg_ptr != ssv)
433 sv_setref_iv(obj, "threads::shared::tie", PTR2IV(ssv));
435 sv_unmagic(sv, PERL_MAGIC_tied);
437 mg = sv_magicext(sv, obj, PERL_MAGIC_tied, &sharedsv_array_vtbl,
439 mg->mg_flags |= (MGf_COPY|MGf_DUP);
440 SvREFCNT_inc_void(ssv);
446 if ((SvTYPE(sv) < SVt_PVMG)
447 || !(mg = mg_find(sv, PERL_MAGIC_shared_scalar))
448 || mg->mg_virtual != &sharedsv_scalar_vtbl
449 || (SV*) mg->mg_ptr != ssv)
452 sv_unmagic(sv, PERL_MAGIC_shared_scalar);
454 mg = sv_magicext(sv, Nullsv, PERL_MAGIC_shared_scalar,
455 &sharedsv_scalar_vtbl, (char *)ssv, 0);
456 mg->mg_flags |= (MGf_DUP
461 SvREFCNT_inc_void(ssv);
466 assert ( Perl_sharedsv_find(aTHX_ sv) == ssv );
470 /* Given a private SV, create and return an associated shared SV.
471 * Assumes lock is held.
474 S_sharedsv_new_shared(pTHX_ SV *sv)
479 assert(PL_sharedsv_lock.owner == aTHX);
480 assert(aTHX != PL_sharedsv_space);
484 SvREFCNT(ssv) = 0; /* Will be upped to 1 by Perl_sharedsv_associate */
485 sv_upgrade(ssv, SvTYPE(sv));
487 Perl_sharedsv_associate(aTHX_ sv, ssv);
492 /* Given a shared SV, create and return an associated private SV.
493 * Assumes lock is held.
496 S_sharedsv_new_private(pTHX_ SV *ssv)
500 assert(PL_sharedsv_lock.owner == aTHX);
501 assert(aTHX != PL_sharedsv_space);
504 sv_upgrade(sv, SvTYPE(ssv));
505 Perl_sharedsv_associate(aTHX_ sv, ssv);
510 /* A threadsafe version of SvREFCNT_dec(ssv) */
513 S_sharedsv_dec(pTHX_ SV* ssv)
518 if (SvREFCNT(ssv) > 1) {
519 /* No side effects, so can do it lightweight */
531 /* Implements Perl-level share() and :shared */
534 Perl_sharedsv_share(pTHX_ SV *sv)
538 Perl_croak(aTHX_ "Cannot share globs yet");
542 Perl_croak(aTHX_ "Cannot share subs yet");
547 (void) S_sharedsv_new_shared(aTHX_ sv);
556 /* Number of milliseconds from 1/1/1601 to 1/1/1970 */
557 #define EPOCH_BIAS 11644473600000.
559 /* Returns relative time in milliseconds. (Adapted from Time::HiRes.) */
561 S_abs_2_rel_milli(double abs)
565 /* Get current time (in units of 100 nanoseconds since 1/1/1601) */
568 __int64 i64; /* 'signed' to keep compilers happy */
571 GetSystemTimeAsFileTime(&now.ft);
573 /* Relative time in milliseconds */
574 rel = (abs * 1000.) - (((double)now.i64 / 10000.) - EPOCH_BIAS);
583 # define ABS2RELMILLI(abs) \
585 abs -= (double)time(NULL); \
586 if (abs > 0) { abs *= 1000; } \
592 /* Do OS-specific condition timed wait */
595 Perl_sharedsv_cond_timedwait(perl_cond *cond, perl_mutex *mut, double abs)
597 #if defined(NETWARE) || defined(FAKE_THREADS) || defined(I_MACH_CTHREADS)
598 Perl_croak_nocontext("cond_timedwait not supported on this platform");
605 /* See comments in win32/win32thread.h COND_WAIT vis-a-vis race */
606 switch (WaitForSingleObject(cond->sem, S_abs_2_rel_milli(abs))) {
607 case WAIT_OBJECT_0: got_it = 1; break;
608 case WAIT_TIMEOUT: break;
610 /* WAIT_FAILED? WAIT_ABANDONED? others? */
611 Perl_croak_nocontext("panic: cond_timedwait (%ld)",GetLastError());
624 if ((rc = DosResetEventSem(*cond,&n_a)) && (rc != ERROR_ALREADY_RESET))
625 Perl_rc = rc, croak_with_os2error("panic: cond_timedwait-reset");
627 if (CheckOSError(DosWaitEventSem(*cond,abs))
628 && (rc != ERROR_INTERRUPT))
629 croak_with_os2error("panic: cond_timedwait");
630 if (rc == ERROR_INTERRUPT) errno = EINTR;
633 # else /* Hope you're I_PTHREAD! */
637 ts.tv_sec = (long)abs;
638 abs -= (NV)ts.tv_sec;
639 ts.tv_nsec = (long)(abs * 1000000000.0);
641 switch (pthread_cond_timedwait(cond, mut, &ts)) {
642 case 0: got_it = 1; break;
643 case ETIMEDOUT: break;
646 if (errno == ETIMEDOUT || errno == EAGAIN)
650 Perl_croak_nocontext("panic: cond_timedwait");
656 #endif /* NETWARE || FAKE_THREADS || I_MACH_CTHREADS */
660 /* Given a shared RV, copy it's value to a private RV, also copying the
661 * object status of the referent.
662 * If the private side is already an appropriate RV->SV combination, keep
666 S_get_RV(pTHX_ SV *sv, SV *ssv) {
667 SV *sobj = SvRV(ssv);
670 ((obj = SvRV(sv))) &&
671 (Perl_sharedsv_find(aTHX_ obj) == sobj) &&
672 (SvTYPE(obj) == SvTYPE(sobj))))
674 /* Can't reuse obj */
676 SvREFCNT_dec(SvRV(sv));
678 assert(SvTYPE(sv) >= SVt_RV);
679 sv_setsv_nomg(sv, &PL_sv_undef);
682 obj = S_sharedsv_new_private(aTHX_ SvRV(ssv));
687 /* Remove any old blessing */
688 SvREFCNT_dec(SvSTASH(obj));
691 if (SvOBJECT(sobj)) {
692 /* Add any new old blessing */
694 char* stash_ptr = SvPV((SV*) SvSTASH(sobj), len);
695 HV* stash = gv_stashpvn(stash_ptr, len, TRUE);
697 SvSTASH_set(obj, (HV*)SvREFCNT_inc(stash));
702 /* ------------ PERL_MAGIC_shared_scalar(n) functions -------------- */
704 /* Get magic for PERL_MAGIC_shared_scalar(n) */
707 sharedsv_scalar_mg_get(pTHX_ SV *sv, MAGIC *mg)
709 SV *ssv = (SV *) mg->mg_ptr;
714 S_get_RV(aTHX_ sv, ssv);
716 sv_setsv_nomg(sv, ssv);
722 /* Copy the contents of a private SV to a shared SV.
723 * Used by various mg_set()-type functions.
724 * Assumes lock is held.
727 sharedsv_scalar_store(pTHX_ SV *sv, SV *ssv)
732 assert(PL_sharedsv_lock.owner == aTHX);
735 SV *sobj = Perl_sharedsv_find(aTHX_ obj);
738 (void)SvUPGRADE(ssv, SVt_RV);
739 sv_setsv_nomg(ssv, &PL_sv_undef);
741 SvRV_set(ssv, SvREFCNT_inc(sobj));
743 if (SvOBJECT(sobj)) {
744 /* Remove any old blessing */
745 SvREFCNT_dec(SvSTASH(sobj));
749 SV* fake_stash = newSVpv(HvNAME_get(SvSTASH(obj)),0);
751 SvSTASH_set(sobj, (HV*)fake_stash);
760 sv_setsv_nomg(ssv, sv);
762 /* Remove any old blessing */
763 SvREFCNT_dec(SvSTASH(ssv));
767 SV* fake_stash = newSVpv(HvNAME_get(SvSTASH(sv)),0);
769 SvSTASH_set(ssv, (HV*)fake_stash);
774 Perl_croak(aTHX_ "Invalid value for shared scalar");
778 /* Set magic for PERL_MAGIC_shared_scalar(n) */
781 sharedsv_scalar_mg_set(pTHX_ SV *sv, MAGIC *mg)
783 SV *ssv = (SV*)(mg->mg_ptr);
786 if (SvTYPE(ssv) < SvTYPE(sv)) {
789 sv_upgrade(ssv, SvTYPE(sv));
792 sharedsv_scalar_store(aTHX_ sv, ssv);
797 /* Free magic for PERL_MAGIC_shared_scalar(n) */
800 sharedsv_scalar_mg_free(pTHX_ SV *sv, MAGIC *mg)
802 S_sharedsv_dec(aTHX_ (SV*)mg->mg_ptr);
807 * Called during cloning of PERL_MAGIC_shared_scalar(n) magic in new thread
810 sharedsv_scalar_mg_dup(pTHX_ MAGIC *mg, CLONE_PARAMS *param)
812 SvREFCNT_inc_void(mg->mg_ptr);
818 * Called during local $shared
821 sharedsv_scalar_mg_local(pTHX_ SV* nsv, MAGIC *mg)
824 SV *ssv = (SV *) mg->mg_ptr;
827 SvREFCNT_inc_void(ssv);
830 nmg = sv_magicext(nsv, mg->mg_obj, mg->mg_type, mg->mg_virtual,
831 mg->mg_ptr, mg->mg_len);
832 nmg->mg_flags = mg->mg_flags;
833 nmg->mg_private = mg->mg_private;
839 MGVTBL sharedsv_scalar_vtbl = {
840 sharedsv_scalar_mg_get, /* get */
841 sharedsv_scalar_mg_set, /* set */
844 sharedsv_scalar_mg_free, /* free */
846 sharedsv_scalar_mg_dup, /* dup */
848 sharedsv_scalar_mg_local, /* local */
852 /* ------------ PERL_MAGIC_tiedelem(p) functions -------------- */
854 /* Get magic for PERL_MAGIC_tiedelem(p) */
857 sharedsv_elem_mg_FETCH(pTHX_ SV *sv, MAGIC *mg)
860 SV *saggregate = S_sharedsv_from_obj(aTHX_ mg->mg_obj);
864 if (SvTYPE(saggregate) == SVt_PVAV) {
865 assert ( mg->mg_ptr == 0 );
867 svp = av_fetch((AV*) saggregate, mg->mg_len, 0);
869 char *key = mg->mg_ptr;
870 STRLEN len = mg->mg_len;
871 assert ( mg->mg_ptr != 0 );
872 if (mg->mg_len == HEf_SVKEY) {
873 key = SvPV((SV *) mg->mg_ptr, len);
876 svp = hv_fetch((HV*) saggregate, key, len, 0);
880 /* Exists in the array */
882 S_get_RV(aTHX_ sv, *svp);
884 /* XXX Can this branch ever happen? DAPM */
885 /* XXX assert("no such branch"); */
886 Perl_sharedsv_associate(aTHX_ sv, *svp);
890 /* Not in the array */
891 sv_setsv(sv, &PL_sv_undef);
897 /* Set magic for PERL_MAGIC_tiedelem(p) */
900 sharedsv_elem_mg_STORE(pTHX_ SV *sv, MAGIC *mg)
903 SV *saggregate = S_sharedsv_from_obj(aTHX_ mg->mg_obj);
905 /* Theory - SV itself is magically shared - and we have ordered the
906 magic such that by the time we get here it has been stored
907 to its shared counterpart
911 if (SvTYPE(saggregate) == SVt_PVAV) {
912 assert ( mg->mg_ptr == 0 );
914 svp = av_fetch((AV*) saggregate, mg->mg_len, 1);
916 char *key = mg->mg_ptr;
917 STRLEN len = mg->mg_len;
918 assert ( mg->mg_ptr != 0 );
919 if (mg->mg_len == HEf_SVKEY)
920 key = SvPV((SV *) mg->mg_ptr, len);
922 svp = hv_fetch((HV*) saggregate, key, len, 1);
925 Perl_sharedsv_associate(aTHX_ sv, *svp);
926 sharedsv_scalar_store(aTHX_ sv, *svp);
931 /* Clear magic for PERL_MAGIC_tiedelem(p) */
934 sharedsv_elem_mg_DELETE(pTHX_ SV *sv, MAGIC *mg)
938 SV *saggregate = S_sharedsv_from_obj(aTHX_ mg->mg_obj);
940 sharedsv_elem_mg_FETCH(aTHX_ sv, mg);
941 if ((shmg = mg_find(sv, PERL_MAGIC_shared_scalar)))
942 sharedsv_scalar_mg_get(aTHX_ sv, shmg);
943 if (SvTYPE(saggregate) == SVt_PVAV) {
945 av_delete((AV*) saggregate, mg->mg_len, G_DISCARD);
947 char *key = mg->mg_ptr;
948 STRLEN len = mg->mg_len;
949 assert ( mg->mg_ptr != 0 );
950 if (mg->mg_len == HEf_SVKEY)
951 key = SvPV((SV *) mg->mg_ptr, len);
953 hv_delete((HV*) saggregate, key, len, G_DISCARD);
960 /* Called during cloning of PERL_MAGIC_tiedelem(p) magic in new
964 sharedsv_elem_mg_dup(pTHX_ MAGIC *mg, CLONE_PARAMS *param)
966 SvREFCNT_inc_void(S_sharedsv_from_obj(aTHX_ mg->mg_obj));
967 assert(mg->mg_flags & MGf_DUP);
971 MGVTBL sharedsv_elem_vtbl = {
972 sharedsv_elem_mg_FETCH, /* get */
973 sharedsv_elem_mg_STORE, /* set */
975 sharedsv_elem_mg_DELETE, /* clear */
978 sharedsv_elem_mg_dup, /* dup */
984 /* ------------ PERL_MAGIC_tied(P) functions -------------- */
986 /* Len magic for PERL_MAGIC_tied(P) */
989 sharedsv_array_mg_FETCHSIZE(pTHX_ SV *sv, MAGIC *mg)
992 SV *ssv = (SV *) mg->mg_ptr;
995 if (SvTYPE(ssv) == SVt_PVAV) {
996 val = av_len((AV*) ssv);
998 /* Not actually defined by tie API but ... */
999 val = HvKEYS((HV*) ssv);
1005 /* Clear magic for PERL_MAGIC_tied(P) */
1008 sharedsv_array_mg_CLEAR(pTHX_ SV *sv, MAGIC *mg)
1011 SV *ssv = (SV *) mg->mg_ptr;
1013 if (SvTYPE(ssv) == SVt_PVAV) {
1014 av_clear((AV*) ssv);
1016 hv_clear((HV*) ssv);
1022 /* Free magic for PERL_MAGIC_tied(P) */
1025 sharedsv_array_mg_free(pTHX_ SV *sv, MAGIC *mg)
1027 S_sharedsv_dec(aTHX_ (SV*)mg->mg_ptr);
1032 * Copy magic for PERL_MAGIC_tied(P)
1033 * This is called when perl is about to access an element of
1037 sharedsv_array_mg_copy(pTHX_ SV *sv, MAGIC* mg,
1038 SV *nsv, const char *name, int namlen)
1040 MAGIC *nmg = sv_magicext(nsv,mg->mg_obj,
1041 toLOWER(mg->mg_type),&sharedsv_elem_vtbl,
1043 nmg->mg_flags |= MGf_DUP;
1047 /* Called during cloning of PERL_MAGIC_tied(P) magic in new thread */
1050 sharedsv_array_mg_dup(pTHX_ MAGIC *mg, CLONE_PARAMS *param)
1052 SvREFCNT_inc_void((SV*)mg->mg_ptr);
1053 assert(mg->mg_flags & MGf_DUP);
1057 MGVTBL sharedsv_array_vtbl = {
1060 sharedsv_array_mg_FETCHSIZE,/* len */
1061 sharedsv_array_mg_CLEAR, /* clear */
1062 sharedsv_array_mg_free, /* free */
1063 sharedsv_array_mg_copy, /* copy */
1064 sharedsv_array_mg_dup, /* dup */
1071 /* Recursively unlocks a shared sv. */
1074 Perl_sharedsv_unlock(pTHX_ SV *ssv)
1076 user_lock *ul = S_get_userlock(aTHX_ ssv, 0);
1078 recursive_lock_release(aTHX_ &ul->lock);
1082 /* Recursive locks on a sharedsv.
1083 * Locks are dynamically scoped at the level of the first lock.
1086 Perl_sharedsv_lock(pTHX_ SV *ssv)
1091 ul = S_get_userlock(aTHX_ ssv, 1);
1092 recursive_lock_acquire(aTHX_ &ul->lock, __FILE__, __LINE__);
1095 /* Handles calls from lock() builtin via PL_lockhook */
1098 Perl_sharedsv_locksv(pTHX_ SV *sv)
1104 ssv = Perl_sharedsv_find(aTHX_ sv);
1106 croak("lock can only be used on shared values");
1107 Perl_sharedsv_lock(aTHX_ ssv);
1111 /* Can a shared object be destroyed?
1112 * True if not a shared,
1113 * or if detroying last proxy on a shared object
1115 #ifdef PL_destroyhook
1117 Perl_shared_object_destroy(pTHX_ SV *sv)
1123 ssv = Perl_sharedsv_find(aTHX_ sv);
1124 return (!ssv || (SvREFCNT(ssv) <= 1));
1129 /* Saves a space for keeping SVs wider than an interpreter. */
1132 Perl_sharedsv_init(pTHX)
1135 /* This pair leaves us in shared context ... */
1136 PL_sharedsv_space = perl_alloc();
1137 perl_construct(PL_sharedsv_space);
1139 recursive_lock_init(aTHX_ &PL_sharedsv_lock);
1140 PL_lockhook = &Perl_sharedsv_locksv;
1141 PL_sharehook = &Perl_sharedsv_share;
1142 #ifdef PL_destroyhook
1143 PL_destroyhook = &Perl_shared_object_destroy;
1147 #endif /* USE_ITHREADS */
1149 MODULE = threads::shared PACKAGE = threads::shared::tie
1159 SV *sobj = S_sharedsv_from_obj(aTHX_ obj);
1161 for (i = 1; i < items; i++) {
1162 SV* tmp = newSVsv(ST(i));
1165 stmp = S_sharedsv_new_shared(aTHX_ tmp);
1166 sharedsv_scalar_store(aTHX_ tmp, stmp);
1168 av_push((AV*) sobj, stmp);
1169 SvREFCNT_inc_void(stmp);
1176 UNSHIFT(SV *obj, ...)
1179 SV *sobj = S_sharedsv_from_obj(aTHX_ obj);
1183 av_unshift((AV*)sobj, items - 1);
1185 for (i = 1; i < items; i++) {
1186 SV *tmp = newSVsv(ST(i));
1187 SV *stmp = S_sharedsv_new_shared(aTHX_ tmp);
1188 sharedsv_scalar_store(aTHX_ tmp, stmp);
1190 av_store((AV*) sobj, i - 1, stmp);
1191 SvREFCNT_inc_void(stmp);
1202 SV *sobj = S_sharedsv_from_obj(aTHX_ obj);
1206 ssv = av_pop((AV*)sobj);
1208 ST(0) = sv_newmortal();
1209 Perl_sharedsv_associate(aTHX_ ST(0), ssv);
1212 /* XSRETURN(1); - implied */
1219 SV *sobj = S_sharedsv_from_obj(aTHX_ obj);
1223 ssv = av_shift((AV*)sobj);
1225 ST(0) = sv_newmortal();
1226 Perl_sharedsv_associate(aTHX_ ST(0), ssv);
1229 /* XSRETURN(1); - implied */
1233 EXTEND(SV *obj, IV count)
1236 SV *sobj = S_sharedsv_from_obj(aTHX_ obj);
1238 av_extend((AV*)sobj, count);
1243 STORESIZE(SV *obj,IV count)
1246 SV *sobj = S_sharedsv_from_obj(aTHX_ obj);
1248 av_fill((AV*) sobj, count);
1253 EXISTS(SV *obj, SV *index)
1256 SV *sobj = S_sharedsv_from_obj(aTHX_ obj);
1258 if (SvTYPE(sobj) == SVt_PVAV) {
1260 exists = av_exists((AV*) sobj, SvIV(index));
1263 char *key = SvPV(index,len);
1265 exists = hv_exists((HV*) sobj, key, len);
1268 ST(0) = (exists) ? &PL_sv_yes : &PL_sv_no;
1269 /* XSRETURN(1); - implied */
1276 SV *sobj = S_sharedsv_from_obj(aTHX_ obj);
1282 hv_iterinit((HV*) sobj);
1283 entry = hv_iternext((HV*) sobj);
1285 key = hv_iterkey(entry,&len);
1287 ST(0) = sv_2mortal(newSVpv(key, len));
1290 ST(0) = &PL_sv_undef;
1293 /* XSRETURN(1); - implied */
1297 NEXTKEY(SV *obj, SV *oldkey)
1300 SV *sobj = S_sharedsv_from_obj(aTHX_ obj);
1305 PERL_UNUSED_VAR(oldkey);
1309 entry = hv_iternext((HV*) sobj);
1311 key = hv_iterkey(entry,&len);
1313 ST(0) = sv_2mortal(newSVpv(key, len));
1316 ST(0) = &PL_sv_undef;
1319 /* XSRETURN(1); - implied */
1322 MODULE = threads::shared PACKAGE = threads::shared
1332 myref = SvRV(myref);
1334 myref = SvRV(myref);
1335 ssv = Perl_sharedsv_find(aTHX_ myref);
1338 ST(0) = sv_2mortal(newSVuv(PTR2UV(ssv)));
1339 /* XSRETURN(1); - implied */
1348 myref = SvRV(myref);
1350 myref = SvRV(myref);
1351 ssv = Perl_sharedsv_find(aTHX_ myref);
1353 if (ckWARN(WARN_THREADS)) {
1354 Perl_warner(aTHX_ packWARN(WARN_THREADS),
1355 "%" SVf " is not shared", ST(0));
1359 ST(0) = sv_2mortal(newSViv(SvREFCNT(ssv)));
1360 /* XSRETURN(1); - implied */
1368 Perl_croak(aTHX_ "Argument to share needs to be passed as ref");
1369 myref = SvRV(myref);
1371 myref = SvRV(myref);
1372 Perl_sharedsv_share(aTHX_ myref);
1373 ST(0) = sv_2mortal(newRV_inc(myref));
1374 /* XSRETURN(1); - implied */
1378 cond_wait(SV *ref_cond, SV *ref_lock = 0)
1379 PROTOTYPE: \[$@%];\[$@%]
1382 perl_cond* user_condition;
1386 if (!SvROK(ref_cond))
1387 Perl_croak(aTHX_ "Argument to cond_wait needs to be passed as ref");
1388 ref_cond = SvRV(ref_cond);
1389 if (SvROK(ref_cond))
1390 ref_cond = SvRV(ref_cond);
1391 ssv = Perl_sharedsv_find(aTHX_ ref_cond);
1393 Perl_croak(aTHX_ "cond_wait can only be used on shared values");
1394 ul = S_get_userlock(aTHX_ ssv, 1);
1396 user_condition = &ul->user_cond;
1397 if (ref_lock && (ref_cond != ref_lock)) {
1398 if (!SvROK(ref_lock))
1399 Perl_croak(aTHX_ "cond_wait lock needs to be passed as ref");
1400 ref_lock = SvRV(ref_lock);
1401 if (SvROK(ref_lock)) ref_lock = SvRV(ref_lock);
1402 ssv = Perl_sharedsv_find(aTHX_ ref_lock);
1404 Perl_croak(aTHX_ "cond_wait lock must be a shared value");
1405 ul = S_get_userlock(aTHX_ ssv, 1);
1407 if (ul->lock.owner != aTHX)
1408 croak("You need a lock before you can cond_wait");
1410 /* Stealing the members of the lock object worries me - NI-S */
1411 MUTEX_LOCK(&ul->lock.mutex);
1412 ul->lock.owner = NULL;
1413 locks = ul->lock.locks;
1416 /* Since we are releasing the lock here, we need to tell other
1417 * people that it is ok to go ahead and use it */
1418 COND_SIGNAL(&ul->lock.cond);
1419 COND_WAIT(user_condition, &ul->lock.mutex);
1420 while (ul->lock.owner != NULL) {
1421 /* OK -- must reacquire the lock */
1422 COND_WAIT(&ul->lock.cond, &ul->lock.mutex);
1424 ul->lock.owner = aTHX;
1425 ul->lock.locks = locks;
1426 MUTEX_UNLOCK(&ul->lock.mutex);
1430 cond_timedwait(SV *ref_cond, double abs, SV *ref_lock = 0)
1431 PROTOTYPE: \[$@%]$;\[$@%]
1434 perl_cond* user_condition;
1438 if (! SvROK(ref_cond))
1439 Perl_croak(aTHX_ "Argument to cond_timedwait needs to be passed as ref");
1440 ref_cond = SvRV(ref_cond);
1441 if (SvROK(ref_cond))
1442 ref_cond = SvRV(ref_cond);
1443 ssv = Perl_sharedsv_find(aTHX_ ref_cond);
1445 Perl_croak(aTHX_ "cond_timedwait can only be used on shared values");
1446 ul = S_get_userlock(aTHX_ ssv, 1);
1448 user_condition = &ul->user_cond;
1449 if (ref_lock && (ref_cond != ref_lock)) {
1450 if (! SvROK(ref_lock))
1451 Perl_croak(aTHX_ "cond_timedwait lock needs to be passed as ref");
1452 ref_lock = SvRV(ref_lock);
1453 if (SvROK(ref_lock)) ref_lock = SvRV(ref_lock);
1454 ssv = Perl_sharedsv_find(aTHX_ ref_lock);
1456 Perl_croak(aTHX_ "cond_timedwait lock must be a shared value");
1457 ul = S_get_userlock(aTHX_ ssv, 1);
1459 if (ul->lock.owner != aTHX)
1460 Perl_croak(aTHX_ "You need a lock before you can cond_wait");
1462 MUTEX_LOCK(&ul->lock.mutex);
1463 ul->lock.owner = NULL;
1464 locks = ul->lock.locks;
1466 /* Since we are releasing the lock here, we need to tell other
1467 * people that it is ok to go ahead and use it */
1468 COND_SIGNAL(&ul->lock.cond);
1469 RETVAL = Perl_sharedsv_cond_timedwait(user_condition, &ul->lock.mutex, abs);
1470 while (ul->lock.owner != NULL) {
1471 /* OK -- must reacquire the lock... */
1472 COND_WAIT(&ul->lock.cond, &ul->lock.mutex);
1474 ul->lock.owner = aTHX;
1475 ul->lock.locks = locks;
1476 MUTEX_UNLOCK(&ul->lock.mutex);
1485 cond_signal(SV *myref)
1492 Perl_croak(aTHX_ "Argument to cond_signal needs to be passed as ref");
1493 myref = SvRV(myref);
1495 myref = SvRV(myref);
1496 ssv = Perl_sharedsv_find(aTHX_ myref);
1498 Perl_croak(aTHX_ "cond_signal can only be used on shared values");
1499 ul = S_get_userlock(aTHX_ ssv, 1);
1500 if (ckWARN(WARN_THREADS) && ul->lock.owner != aTHX) {
1501 Perl_warner(aTHX_ packWARN(WARN_THREADS),
1502 "cond_signal() called on unlocked variable");
1504 COND_SIGNAL(&ul->user_cond);
1508 cond_broadcast(SV *myref)
1515 Perl_croak(aTHX_ "Argument to cond_broadcast needs to be passed as ref");
1516 myref = SvRV(myref);
1518 myref = SvRV(myref);
1519 ssv = Perl_sharedsv_find(aTHX_ myref);
1521 Perl_croak(aTHX_ "cond_broadcast can only be used on shared values");
1522 ul = S_get_userlock(aTHX_ ssv, 1);
1523 if (ckWARN(WARN_THREADS) && ul->lock.owner != aTHX) {
1524 Perl_warner(aTHX_ packWARN(WARN_THREADS),
1525 "cond_broadcast() called on unlocked variable");
1527 COND_BROADCAST(&ul->user_cond);
1531 bless(SV* myref, ...);
1538 stash = CopSTASH(PL_curcop);
1540 SV* classname = ST(1);
1545 ! SvGMAGICAL(classname) &&
1546 ! SvAMAGIC(classname) &&
1549 Perl_croak(aTHX_ "Attempt to bless into a reference");
1551 ptr = SvPV(classname, len);
1552 if (ckWARN(WARN_MISC) && len == 0) {
1553 Perl_warner(aTHX_ packWARN(WARN_MISC),
1554 "Explicit blessing to '' (assuming package main)");
1556 stash = gv_stashpvn(ptr, len, TRUE);
1558 SvREFCNT_inc_void(myref);
1559 (void)sv_bless(myref, stash);
1560 ST(0) = sv_2mortal(myref);
1561 ssv = Perl_sharedsv_find(aTHX_ myref);
1567 SV* fake_stash = newSVpv(HvNAME_get(stash), 0);
1568 (void)sv_bless(ssv, (HV*)fake_stash);
1573 /* XSRETURN(1); - implied */
1575 #endif /* USE_ITHREADS */
1580 Perl_sharedsv_init(aTHX);
1581 #endif /* USE_ITHREADS */