3 * Copyright (C) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
4 * 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008 by Larry Wall and others
6 * You may distribute under the terms of either the GNU General Public
7 * License or the Artistic License, as specified in the README file.
12 * I sit beside the fire and think
13 * of all that I have seen.
16 * [p.278 of _The Lord of the Rings_, II/iii: "The Ring Goes South"]
20 =head1 Hash Manipulation Functions
22 A HV structure represents a Perl hash. It consists mainly of an array
23 of pointers, each of which points to a linked list of HE structures. The
24 array is indexed by the hash function of the key, so each linked list
25 represents all the hash entries with the same hash value. Each HE contains
26 a pointer to the actual value, plus a pointer to a HEK structure which
27 holds the key and hash value.
35 #define PERL_HASH_INTERNAL_ACCESS
38 #define HV_MAX_LENGTH_BEFORE_SPLIT 14
40 static const char S_strtab_error[]
41 = "Cannot modify shared string table in hv_%s";
45 #define new_HE() (HE*)safemalloc(sizeof(HE))
46 #define del_HE(p) safefree((char*)p)
55 void ** const root = &PL_body_roots[HE_SVSLOT];
58 Perl_more_bodies(aTHX_ HE_SVSLOT, sizeof(HE), PERL_ARENA_SIZE);
65 #define new_HE() new_he()
68 HeNEXT(p) = (HE*)(PL_body_roots[HE_SVSLOT]); \
69 PL_body_roots[HE_SVSLOT] = p; \
77 S_save_hek_flags(const char *str, I32 len, U32 hash, int flags)
79 const int flags_masked = flags & HVhek_MASK;
83 PERL_ARGS_ASSERT_SAVE_HEK_FLAGS;
85 Newx(k, HEK_BASESIZE + len + 2, char);
87 Copy(str, HEK_KEY(hek), len, char);
88 HEK_KEY(hek)[len] = 0;
91 HEK_FLAGS(hek) = (unsigned char)flags_masked | HVhek_UNSHARED;
93 if (flags & HVhek_FREEKEY)
98 /* free the pool of temporary HE/HEK pairs returned by hv_fetch_ent
102 Perl_free_tied_hv_pool(pTHX)
105 HE *he = PL_hv_fetch_ent_mh;
108 Safefree(HeKEY_hek(he));
112 PL_hv_fetch_ent_mh = NULL;
115 #if defined(USE_ITHREADS)
117 Perl_hek_dup(pTHX_ HEK *source, CLONE_PARAMS* param)
121 PERL_ARGS_ASSERT_HEK_DUP;
122 PERL_UNUSED_ARG(param);
127 shared = (HEK*)ptr_table_fetch(PL_ptr_table, source);
129 /* We already shared this hash key. */
130 (void)share_hek_hek(shared);
134 = share_hek_flags(HEK_KEY(source), HEK_LEN(source),
135 HEK_HASH(source), HEK_FLAGS(source));
136 ptr_table_store(PL_ptr_table, source, shared);
142 Perl_he_dup(pTHX_ const HE *e, bool shared, CLONE_PARAMS* param)
146 PERL_ARGS_ASSERT_HE_DUP;
150 /* look for it in the table first */
151 ret = (HE*)ptr_table_fetch(PL_ptr_table, e);
155 /* create anew and remember what it is */
157 ptr_table_store(PL_ptr_table, e, ret);
159 HeNEXT(ret) = he_dup(HeNEXT(e),shared, param);
160 if (HeKLEN(e) == HEf_SVKEY) {
162 Newx(k, HEK_BASESIZE + sizeof(const SV *), char);
163 HeKEY_hek(ret) = (HEK*)k;
164 HeKEY_sv(ret) = sv_dup_inc(HeKEY_sv(e), param);
167 /* This is hek_dup inlined, which seems to be important for speed
169 HEK * const source = HeKEY_hek(e);
170 HEK *shared = (HEK*)ptr_table_fetch(PL_ptr_table, source);
173 /* We already shared this hash key. */
174 (void)share_hek_hek(shared);
178 = share_hek_flags(HEK_KEY(source), HEK_LEN(source),
179 HEK_HASH(source), HEK_FLAGS(source));
180 ptr_table_store(PL_ptr_table, source, shared);
182 HeKEY_hek(ret) = shared;
185 HeKEY_hek(ret) = save_hek_flags(HeKEY(e), HeKLEN(e), HeHASH(e),
187 HeVAL(ret) = sv_dup_inc(HeVAL(e), param);
190 #endif /* USE_ITHREADS */
193 S_hv_notallowed(pTHX_ int flags, const char *key, I32 klen,
196 SV * const sv = sv_newmortal();
198 PERL_ARGS_ASSERT_HV_NOTALLOWED;
200 if (!(flags & HVhek_FREEKEY)) {
201 sv_setpvn(sv, key, klen);
204 /* Need to free saved eventually assign to mortal SV */
205 /* XXX is this line an error ???: SV *sv = sv_newmortal(); */
206 sv_usepvn(sv, (char *) key, klen);
208 if (flags & HVhek_UTF8) {
211 Perl_croak(aTHX_ msg, SVfARG(sv));
214 /* (klen == HEf_SVKEY) is special for MAGICAL hv entries, meaning key slot
220 Stores an SV in a hash. The hash key is specified as C<key> and C<klen> is
221 the length of the key. The C<hash> parameter is the precomputed hash
222 value; if it is zero then Perl will compute it. The return value will be
223 NULL if the operation failed or if the value did not need to be actually
224 stored within the hash (as in the case of tied hashes). Otherwise it can
225 be dereferenced to get the original C<SV*>. Note that the caller is
226 responsible for suitably incrementing the reference count of C<val> before
227 the call, and decrementing it if the function returned NULL. Effectively
228 a successful hv_store takes ownership of one reference to C<val>. This is
229 usually what you want; a newly created SV has a reference count of one, so
230 if all your code does is create SVs then store them in a hash, hv_store
231 will own the only reference to the new SV, and your code doesn't need to do
232 anything further to tidy up. hv_store is not implemented as a call to
233 hv_store_ent, and does not create a temporary SV for the key, so if your
234 key data is not already in SV form then use hv_store in preference to
237 See L<perlguts/"Understanding the Magic of Tied Hashes and Arrays"> for more
238 information on how to use this function on tied hashes.
240 =for apidoc hv_store_ent
242 Stores C<val> in a hash. The hash key is specified as C<key>. The C<hash>
243 parameter is the precomputed hash value; if it is zero then Perl will
244 compute it. The return value is the new hash entry so created. It will be
245 NULL if the operation failed or if the value did not need to be actually
246 stored within the hash (as in the case of tied hashes). Otherwise the
247 contents of the return value can be accessed using the C<He?> macros
248 described here. Note that the caller is responsible for suitably
249 incrementing the reference count of C<val> before the call, and
250 decrementing it if the function returned NULL. Effectively a successful
251 hv_store_ent takes ownership of one reference to C<val>. This is
252 usually what you want; a newly created SV has a reference count of one, so
253 if all your code does is create SVs then store them in a hash, hv_store
254 will own the only reference to the new SV, and your code doesn't need to do
255 anything further to tidy up. Note that hv_store_ent only reads the C<key>;
256 unlike C<val> it does not take ownership of it, so maintaining the correct
257 reference count on C<key> is entirely the caller's responsibility. hv_store
258 is not implemented as a call to hv_store_ent, and does not create a temporary
259 SV for the key, so if your key data is not already in SV form then use
260 hv_store in preference to hv_store_ent.
262 See L<perlguts/"Understanding the Magic of Tied Hashes and Arrays"> for more
263 information on how to use this function on tied hashes.
265 =for apidoc hv_exists
267 Returns a boolean indicating whether the specified hash key exists. The
268 C<klen> is the length of the key.
272 Returns the SV which corresponds to the specified key in the hash. The
273 C<klen> is the length of the key. If C<lval> is set then the fetch will be
274 part of a store. Check that the return value is non-null before
275 dereferencing it to an C<SV*>.
277 See L<perlguts/"Understanding the Magic of Tied Hashes and Arrays"> for more
278 information on how to use this function on tied hashes.
280 =for apidoc hv_exists_ent
282 Returns a boolean indicating whether the specified hash key exists. C<hash>
283 can be a valid precomputed hash value, or 0 to ask for it to be
289 /* returns an HE * structure with the all fields set */
290 /* note that hent_val will be a mortal sv for MAGICAL hashes */
292 =for apidoc hv_fetch_ent
294 Returns the hash entry which corresponds to the specified key in the hash.
295 C<hash> must be a valid precomputed hash number for the given C<key>, or 0
296 if you want the function to compute it. IF C<lval> is set then the fetch
297 will be part of a store. Make sure the return value is non-null before
298 accessing it. The return value when C<hv> is a tied hash is a pointer to a
299 static location, so be sure to make a copy of the structure if you need to
302 See L<perlguts/"Understanding the Magic of Tied Hashes and Arrays"> for more
303 information on how to use this function on tied hashes.
308 /* Common code for hv_delete()/hv_exists()/hv_fetch()/hv_store() */
310 Perl_hv_common_key_len(pTHX_ HV *hv, const char *key, I32 klen_i32,
311 const int action, SV *val, const U32 hash)
316 PERL_ARGS_ASSERT_HV_COMMON_KEY_LEN;
325 return hv_common(hv, NULL, key, klen, flags, action, val, hash);
329 Perl_hv_common(pTHX_ HV *hv, SV *keysv, const char *key, STRLEN klen,
330 int flags, int action, SV *val, register U32 hash)
339 const int return_svp = action & HV_FETCH_JUST_SV;
343 if (SvTYPE(hv) == SVTYPEMASK)
346 assert(SvTYPE(hv) == SVt_PVHV);
348 if (SvSMAGICAL(hv) && SvGMAGICAL(hv) && !(action & HV_DISABLE_UVAR_XKEY)) {
350 if ((mg = mg_find((const SV *)hv, PERL_MAGIC_uvar))) {
351 struct ufuncs * const uf = (struct ufuncs *)mg->mg_ptr;
352 if (uf->uf_set == NULL) {
353 SV* obj = mg->mg_obj;
356 keysv = newSVpvn_flags(key, klen, SVs_TEMP |
357 ((flags & HVhek_UTF8)
361 mg->mg_obj = keysv; /* pass key */
362 uf->uf_index = action; /* pass action */
363 magic_getuvar(MUTABLE_SV(hv), mg);
364 keysv = mg->mg_obj; /* may have changed */
367 /* If the key may have changed, then we need to invalidate
368 any passed-in computed hash value. */
374 if (flags & HVhek_FREEKEY)
376 key = SvPV_const(keysv, klen);
377 is_utf8 = (SvUTF8(keysv) != 0);
378 if (SvIsCOW_shared_hash(keysv)) {
379 flags = HVhek_KEYCANONICAL | (is_utf8 ? HVhek_UTF8 : 0);
384 is_utf8 = ((flags & HVhek_UTF8) ? TRUE : FALSE);
387 if (action & HV_DELETE) {
388 return (void *) hv_delete_common(hv, keysv, key, klen,
389 flags | (is_utf8 ? HVhek_UTF8 : 0),
393 xhv = (XPVHV*)SvANY(hv);
395 if (SvRMAGICAL(hv) && !(action & (HV_FETCH_ISSTORE|HV_FETCH_ISEXISTS))) {
396 if (mg_find((const SV *)hv, PERL_MAGIC_tied)
397 || SvGMAGICAL((const SV *)hv))
399 /* FIXME should be able to skimp on the HE/HEK here when
400 HV_FETCH_JUST_SV is true. */
402 keysv = newSVpvn_utf8(key, klen, is_utf8);
404 keysv = newSVsv(keysv);
407 mg_copy(MUTABLE_SV(hv), sv, (char *)keysv, HEf_SVKEY);
409 /* grab a fake HE/HEK pair from the pool or make a new one */
410 entry = PL_hv_fetch_ent_mh;
412 PL_hv_fetch_ent_mh = HeNEXT(entry);
416 Newx(k, HEK_BASESIZE + sizeof(const SV *), char);
417 HeKEY_hek(entry) = (HEK*)k;
419 HeNEXT(entry) = NULL;
420 HeSVKEY_set(entry, keysv);
422 sv_upgrade(sv, SVt_PVLV);
424 /* so we can free entry when freeing sv */
425 LvTARG(sv) = MUTABLE_SV(entry);
427 /* XXX remove at some point? */
428 if (flags & HVhek_FREEKEY)
432 return entry ? (void *) &HeVAL(entry) : NULL;
434 return (void *) entry;
436 #ifdef ENV_IS_CASELESS
437 else if (mg_find((const SV *)hv, PERL_MAGIC_env)) {
439 for (i = 0; i < klen; ++i)
440 if (isLOWER(key[i])) {
441 /* Would be nice if we had a routine to do the
442 copy and upercase in a single pass through. */
443 const char * const nkey = strupr(savepvn(key,klen));
444 /* Note that this fetch is for nkey (the uppercased
445 key) whereas the store is for key (the original) */
446 void *result = hv_common(hv, NULL, nkey, klen,
447 HVhek_FREEKEY, /* free nkey */
448 0 /* non-LVAL fetch */
449 | HV_DISABLE_UVAR_XKEY
452 0 /* compute hash */);
453 if (!result && (action & HV_FETCH_LVALUE)) {
454 /* This call will free key if necessary.
455 Do it this way to encourage compiler to tail
457 result = hv_common(hv, keysv, key, klen, flags,
459 | HV_DISABLE_UVAR_XKEY
463 if (flags & HVhek_FREEKEY)
471 else if (SvRMAGICAL(hv) && (action & HV_FETCH_ISEXISTS)) {
472 if (mg_find((const SV *)hv, PERL_MAGIC_tied)
473 || SvGMAGICAL((const SV *)hv)) {
474 /* I don't understand why hv_exists_ent has svret and sv,
475 whereas hv_exists only had one. */
476 SV * const svret = sv_newmortal();
479 if (keysv || is_utf8) {
481 keysv = newSVpvn_utf8(key, klen, TRUE);
483 keysv = newSVsv(keysv);
485 mg_copy(MUTABLE_SV(hv), sv, (char *)sv_2mortal(keysv), HEf_SVKEY);
487 mg_copy(MUTABLE_SV(hv), sv, key, klen);
489 if (flags & HVhek_FREEKEY)
491 magic_existspack(svret, mg_find(sv, PERL_MAGIC_tiedelem));
492 /* This cast somewhat evil, but I'm merely using NULL/
493 not NULL to return the boolean exists.
494 And I know hv is not NULL. */
495 return SvTRUE(svret) ? (void *)hv : NULL;
497 #ifdef ENV_IS_CASELESS
498 else if (mg_find((const SV *)hv, PERL_MAGIC_env)) {
499 /* XXX This code isn't UTF8 clean. */
500 char * const keysave = (char * const)key;
501 /* Will need to free this, so set FREEKEY flag. */
502 key = savepvn(key,klen);
503 key = (const char*)strupr((char*)key);
508 if (flags & HVhek_FREEKEY) {
511 flags |= HVhek_FREEKEY;
515 else if (action & HV_FETCH_ISSTORE) {
518 hv_magic_check (hv, &needs_copy, &needs_store);
520 const bool save_taint = PL_tainted;
521 if (keysv || is_utf8) {
523 keysv = newSVpvn_utf8(key, klen, TRUE);
526 PL_tainted = SvTAINTED(keysv);
527 keysv = sv_2mortal(newSVsv(keysv));
528 mg_copy(MUTABLE_SV(hv), val, (char*)keysv, HEf_SVKEY);
530 mg_copy(MUTABLE_SV(hv), val, key, klen);
533 TAINT_IF(save_taint);
535 if (flags & HVhek_FREEKEY)
539 #ifdef ENV_IS_CASELESS
540 else if (mg_find((const SV *)hv, PERL_MAGIC_env)) {
541 /* XXX This code isn't UTF8 clean. */
542 const char *keysave = key;
543 /* Will need to free this, so set FREEKEY flag. */
544 key = savepvn(key,klen);
545 key = (const char*)strupr((char*)key);
550 if (flags & HVhek_FREEKEY) {
553 flags |= HVhek_FREEKEY;
561 if ((action & (HV_FETCH_LVALUE | HV_FETCH_ISSTORE))
562 #ifdef DYNAMIC_ENV_FETCH /* if it's an %ENV lookup, we may get it on the fly */
563 || (SvRMAGICAL((const SV *)hv)
564 && mg_find((const SV *)hv, PERL_MAGIC_env))
569 PERL_HV_ARRAY_ALLOC_BYTES(xhv->xhv_max+1 /* HvMAX(hv)+1 */),
571 HvARRAY(hv) = (HE**)array;
573 #ifdef DYNAMIC_ENV_FETCH
574 else if (action & HV_FETCH_ISEXISTS) {
575 /* for an %ENV exists, if we do an insert it's by a recursive
576 store call, so avoid creating HvARRAY(hv) right now. */
580 /* XXX remove at some point? */
581 if (flags & HVhek_FREEKEY)
588 if (is_utf8 & !(flags & HVhek_KEYCANONICAL)) {
589 char * const keysave = (char *)key;
590 key = (char*)bytes_from_utf8((U8*)key, &klen, &is_utf8);
594 flags &= ~HVhek_UTF8;
595 if (key != keysave) {
596 if (flags & HVhek_FREEKEY)
598 flags |= HVhek_WASUTF8 | HVhek_FREEKEY;
599 /* If the caller calculated a hash, it was on the sequence of
600 octets that are the UTF-8 form. We've now changed the sequence
601 of octets stored to that of the equivalent byte representation,
602 so the hash we need is different. */
608 PERL_HASH_INTERNAL(hash, key, klen);
609 /* We don't have a pointer to the hv, so we have to replicate the
610 flag into every HEK, so that hv_iterkeysv can see it. */
611 /* And yes, you do need this even though you are not "storing" because
612 you can flip the flags below if doing an lval lookup. (And that
613 was put in to give the semantics Andreas was expecting.) */
614 flags |= HVhek_REHASH;
616 if (keysv && (SvIsCOW_shared_hash(keysv))) {
617 hash = SvSHARED_HASH(keysv);
619 PERL_HASH(hash, key, klen);
623 masked_flags = (flags & HVhek_MASK);
625 #ifdef DYNAMIC_ENV_FETCH
626 if (!HvARRAY(hv)) entry = NULL;
630 entry = (HvARRAY(hv))[hash & (I32) HvMAX(hv)];
632 for (; entry; entry = HeNEXT(entry)) {
633 if (HeHASH(entry) != hash) /* strings can't be equal */
635 if (HeKLEN(entry) != (I32)klen)
637 if (HeKEY(entry) != key && memNE(HeKEY(entry),key,klen)) /* is this it? */
639 if ((HeKFLAGS(entry) ^ masked_flags) & HVhek_UTF8)
642 if (action & (HV_FETCH_LVALUE|HV_FETCH_ISSTORE)) {
643 if (HeKFLAGS(entry) != masked_flags) {
644 /* We match if HVhek_UTF8 bit in our flags and hash key's
645 match. But if entry was set previously with HVhek_WASUTF8
646 and key now doesn't (or vice versa) then we should change
647 the key's flag, as this is assignment. */
648 if (HvSHAREKEYS(hv)) {
649 /* Need to swap the key we have for a key with the flags we
650 need. As keys are shared we can't just write to the
651 flag, so we share the new one, unshare the old one. */
652 HEK * const new_hek = share_hek_flags(key, klen, hash,
654 unshare_hek (HeKEY_hek(entry));
655 HeKEY_hek(entry) = new_hek;
657 else if (hv == PL_strtab) {
658 /* PL_strtab is usually the only hash without HvSHAREKEYS,
659 so putting this test here is cheap */
660 if (flags & HVhek_FREEKEY)
662 Perl_croak(aTHX_ S_strtab_error,
663 action & HV_FETCH_LVALUE ? "fetch" : "store");
666 HeKFLAGS(entry) = masked_flags;
667 if (masked_flags & HVhek_ENABLEHVKFLAGS)
670 if (HeVAL(entry) == &PL_sv_placeholder) {
671 /* yes, can store into placeholder slot */
672 if (action & HV_FETCH_LVALUE) {
674 /* This preserves behaviour with the old hv_fetch
675 implementation which at this point would bail out
676 with a break; (at "if we find a placeholder, we
677 pretend we haven't found anything")
679 That break mean that if a placeholder were found, it
680 caused a call into hv_store, which in turn would
681 check magic, and if there is no magic end up pretty
682 much back at this point (in hv_store's code). */
685 /* LVAL fetch which actaully needs a store. */
687 HvPLACEHOLDERS(hv)--;
690 if (val != &PL_sv_placeholder)
691 HvPLACEHOLDERS(hv)--;
694 } else if (action & HV_FETCH_ISSTORE) {
695 SvREFCNT_dec(HeVAL(entry));
698 } else if (HeVAL(entry) == &PL_sv_placeholder) {
699 /* if we find a placeholder, we pretend we haven't found
703 if (flags & HVhek_FREEKEY)
706 return entry ? (void *) &HeVAL(entry) : NULL;
710 #ifdef DYNAMIC_ENV_FETCH /* %ENV lookup? If so, try to fetch the value now */
711 if (!(action & HV_FETCH_ISSTORE)
712 && SvRMAGICAL((const SV *)hv)
713 && mg_find((const SV *)hv, PERL_MAGIC_env)) {
715 const char * const env = PerlEnv_ENVgetenv_len(key,&len);
717 sv = newSVpvn(env,len);
719 return hv_common(hv, keysv, key, klen, flags,
720 HV_FETCH_ISSTORE|HV_DISABLE_UVAR_XKEY|return_svp,
726 if (!entry && SvREADONLY(hv) && !(action & HV_FETCH_ISEXISTS)) {
727 hv_notallowed(flags, key, klen,
728 "Attempt to access disallowed key '%"SVf"' in"
729 " a restricted hash");
731 if (!(action & (HV_FETCH_LVALUE|HV_FETCH_ISSTORE))) {
732 /* Not doing some form of store, so return failure. */
733 if (flags & HVhek_FREEKEY)
737 if (action & HV_FETCH_LVALUE) {
740 /* At this point the old hv_fetch code would call to hv_store,
741 which in turn might do some tied magic. So we need to make that
742 magic check happen. */
743 /* gonna assign to this, so it better be there */
744 /* If a fetch-as-store fails on the fetch, then the action is to
745 recurse once into "hv_store". If we didn't do this, then that
746 recursive call would call the key conversion routine again.
747 However, as we replace the original key with the converted
748 key, this would result in a double conversion, which would show
749 up as a bug if the conversion routine is not idempotent. */
750 return hv_common(hv, keysv, key, klen, flags,
751 HV_FETCH_ISSTORE|HV_DISABLE_UVAR_XKEY|return_svp,
753 /* XXX Surely that could leak if the fetch-was-store fails?
754 Just like the hv_fetch. */
758 /* Welcome to hv_store... */
761 /* Not sure if we can get here. I think the only case of oentry being
762 NULL is for %ENV with dynamic env fetch. But that should disappear
763 with magic in the previous code. */
766 PERL_HV_ARRAY_ALLOC_BYTES(xhv->xhv_max+1 /* HvMAX(hv)+1 */),
768 HvARRAY(hv) = (HE**)array;
771 oentry = &(HvARRAY(hv))[hash & (I32) xhv->xhv_max];
774 /* share_hek_flags will do the free for us. This might be considered
777 HeKEY_hek(entry) = share_hek_flags(key, klen, hash, flags);
778 else if (hv == PL_strtab) {
779 /* PL_strtab is usually the only hash without HvSHAREKEYS, so putting
780 this test here is cheap */
781 if (flags & HVhek_FREEKEY)
783 Perl_croak(aTHX_ S_strtab_error,
784 action & HV_FETCH_LVALUE ? "fetch" : "store");
786 else /* gotta do the real thing */
787 HeKEY_hek(entry) = save_hek_flags(key, klen, hash, flags);
789 HeNEXT(entry) = *oentry;
792 if (val == &PL_sv_placeholder)
793 HvPLACEHOLDERS(hv)++;
794 if (masked_flags & HVhek_ENABLEHVKFLAGS)
798 const HE *counter = HeNEXT(entry);
800 xhv->xhv_keys++; /* HvTOTALKEYS(hv)++ */
801 if (!counter) { /* initial entry? */
802 } else if (xhv->xhv_keys > xhv->xhv_max) {
804 } else if(!HvREHASH(hv)) {
807 while ((counter = HeNEXT(counter)))
810 if (n_links > HV_MAX_LENGTH_BEFORE_SPLIT) {
811 /* Use only the old HvKEYS(hv) > HvMAX(hv) condition to limit
812 bucket splits on a rehashed hash, as we're not going to
813 split it again, and if someone is lucky (evil) enough to
814 get all the keys in one list they could exhaust our memory
815 as we repeatedly double the number of buckets on every
816 entry. Linear search feels a less worse thing to do. */
823 return entry ? (void *) &HeVAL(entry) : NULL;
825 return (void *) entry;
829 S_hv_magic_check(HV *hv, bool *needs_copy, bool *needs_store)
831 const MAGIC *mg = SvMAGIC(hv);
833 PERL_ARGS_ASSERT_HV_MAGIC_CHECK;
838 if (isUPPER(mg->mg_type)) {
840 if (mg->mg_type == PERL_MAGIC_tied) {
841 *needs_store = FALSE;
842 return; /* We've set all there is to set. */
845 mg = mg->mg_moremagic;
850 =for apidoc hv_scalar
852 Evaluates the hash in scalar context and returns the result. Handles magic when the hash is tied.
858 Perl_hv_scalar(pTHX_ HV *hv)
862 PERL_ARGS_ASSERT_HV_SCALAR;
864 if (SvRMAGICAL(hv)) {
865 MAGIC * const mg = mg_find((const SV *)hv, PERL_MAGIC_tied);
867 return magic_scalarpack(hv, mg);
871 if (HvTOTALKEYS((const HV *)hv))
872 Perl_sv_setpvf(aTHX_ sv, "%ld/%ld",
873 (long)HvFILL(hv), (long)HvMAX(hv) + 1);
881 =for apidoc hv_delete
883 Deletes a key/value pair in the hash. The value's SV is removed from the
884 hash, made mortal, and returned to the caller. The C<klen> is the length of
885 the key. The C<flags> value will normally be zero; if set to G_DISCARD then
886 NULL will be returned. NULL will also be returned if the key is not found.
888 =for apidoc hv_delete_ent
890 Deletes a key/value pair in the hash. The value SV is removed from the hash,
891 made mortal, and returned to the caller. The C<flags> value will normally be
892 zero; if set to G_DISCARD then NULL will be returned. NULL will also be
893 returned if the key is not found. C<hash> can be a valid precomputed hash
894 value, or 0 to ask for it to be computed.
900 S_hv_delete_common(pTHX_ HV *hv, SV *keysv, const char *key, STRLEN klen,
901 int k_flags, I32 d_flags, U32 hash)
906 register HE **oentry;
907 HE *const *first_entry;
908 bool is_utf8 = (k_flags & HVhek_UTF8) ? TRUE : FALSE;
911 if (SvRMAGICAL(hv)) {
914 hv_magic_check (hv, &needs_copy, &needs_store);
918 entry = (HE *) hv_common(hv, keysv, key, klen,
919 k_flags & ~HVhek_FREEKEY,
920 HV_FETCH_LVALUE|HV_DISABLE_UVAR_XKEY,
922 sv = entry ? HeVAL(entry) : NULL;
928 if (mg_find(sv, PERL_MAGIC_tiedelem)) {
929 /* No longer an element */
930 sv_unmagic(sv, PERL_MAGIC_tiedelem);
933 return NULL; /* element cannot be deleted */
935 #ifdef ENV_IS_CASELESS
936 else if (mg_find((const SV *)hv, PERL_MAGIC_env)) {
937 /* XXX This code isn't UTF8 clean. */
938 keysv = newSVpvn_flags(key, klen, SVs_TEMP);
939 if (k_flags & HVhek_FREEKEY) {
942 key = strupr(SvPVX(keysv));
951 xhv = (XPVHV*)SvANY(hv);
956 const char * const keysave = key;
957 key = (char*)bytes_from_utf8((U8*)key, &klen, &is_utf8);
960 k_flags |= HVhek_UTF8;
962 k_flags &= ~HVhek_UTF8;
963 if (key != keysave) {
964 if (k_flags & HVhek_FREEKEY) {
965 /* This shouldn't happen if our caller does what we expect,
966 but strictly the API allows it. */
969 k_flags |= HVhek_WASUTF8 | HVhek_FREEKEY;
971 HvHASKFLAGS_on(MUTABLE_SV(hv));
975 PERL_HASH_INTERNAL(hash, key, klen);
977 if (keysv && (SvIsCOW_shared_hash(keysv))) {
978 hash = SvSHARED_HASH(keysv);
980 PERL_HASH(hash, key, klen);
984 masked_flags = (k_flags & HVhek_MASK);
986 first_entry = oentry = &(HvARRAY(hv))[hash & (I32) HvMAX(hv)];
988 for (; entry; oentry = &HeNEXT(entry), entry = *oentry) {
991 const char *name = NULL;
995 if (HeHASH(entry) != hash) /* strings can't be equal */
997 if (HeKLEN(entry) != (I32)klen)
999 if (HeKEY(entry) != key && memNE(HeKEY(entry),key,klen)) /* is this it? */
1001 if ((HeKFLAGS(entry) ^ masked_flags) & HVhek_UTF8)
1004 if (hv == PL_strtab) {
1005 if (k_flags & HVhek_FREEKEY)
1007 Perl_croak(aTHX_ S_strtab_error, "delete");
1010 /* if placeholder is here, it's already been deleted.... */
1011 if (HeVAL(entry) == &PL_sv_placeholder) {
1012 if (k_flags & HVhek_FREEKEY)
1016 if (SvREADONLY(hv) && HeVAL(entry) && SvREADONLY(HeVAL(entry))) {
1017 hv_notallowed(k_flags, key, klen,
1018 "Attempt to delete readonly key '%"SVf"' from"
1019 " a restricted hash");
1021 if (k_flags & HVhek_FREEKEY)
1024 /* If this is a stash and the key ends with ::, then someone is
1025 * deleting a package.
1026 * Check whether the gv (HeVAL(entry)) is still in the symbol
1027 * table and then save the name to pass to mro_package_moved after
1029 * We cannot pass the gv to mro_package_moved directly, as that
1030 * function also checks whether the gv is to be found at the loca-
1031 * tion its name indicates, which will no longer be the case once
1032 * this element is deleted. So we have to do that check here.
1034 if (HeVAL(entry) && HvENAME_get(hv)) {
1036 if (keysv) key = SvPV(keysv, klen);
1037 if (klen > 1 && key[klen-2] == ':' && key[klen-1] == ':'
1038 && (klen != 6 || hv!=PL_defstash || memNE(key,"main::",6))
1039 && SvTYPE(sv) == SVt_PVGV && (stash = GvHV((GV *)sv))
1040 && HvENAME_get(stash)) {
1041 SV * const namesv = sv_newmortal();
1042 gv_fullname4(namesv, (GV *)sv, NULL, 0);
1044 gv_fetchsv(namesv, GV_NOADD_NOINIT, SVt_PVGV)
1048 name = SvPV_const(namesv, namlen);
1049 namlen -= 2; /* skip trailing :: */
1050 /* Hang on to it for a bit. */
1051 SvREFCNT_inc_simple_void_NN(
1052 sv_2mortal((SV *)stash)
1058 if (d_flags & G_DISCARD)
1061 sv = sv_2mortal(HeVAL(entry));
1062 HeVAL(entry) = &PL_sv_placeholder;
1066 * If a restricted hash, rather than really deleting the entry, put
1067 * a placeholder there. This marks the key as being "approved", so
1068 * we can still access via not-really-existing key without raising
1071 if (SvREADONLY(hv)) {
1072 SvREFCNT_dec(HeVAL(entry));
1073 HeVAL(entry) = &PL_sv_placeholder;
1074 /* We'll be saving this slot, so the number of allocated keys
1075 * doesn't go down, but the number placeholders goes up */
1076 HvPLACEHOLDERS(hv)++;
1078 *oentry = HeNEXT(entry);
1079 if (SvOOK(hv) && entry == HvAUX(hv)->xhv_eiter /* HvEITER(hv) */)
1082 hv_free_ent(hv, entry);
1083 xhv->xhv_keys--; /* HvTOTALKEYS(hv)-- */
1084 if (xhv->xhv_keys == 0)
1085 HvHASKFLAGS_off(hv);
1088 if (mpm) mro_package_moved(NULL, stash, NULL, name, namlen);
1092 if (SvREADONLY(hv)) {
1093 hv_notallowed(k_flags, key, klen,
1094 "Attempt to delete disallowed key '%"SVf"' from"
1095 " a restricted hash");
1098 if (k_flags & HVhek_FREEKEY)
1104 S_hsplit(pTHX_ HV *hv)
1107 register XPVHV* const xhv = (XPVHV*)SvANY(hv);
1108 const I32 oldsize = (I32) xhv->xhv_max+1; /* HvMAX(hv)+1 (sick) */
1109 register I32 newsize = oldsize * 2;
1111 char *a = (char*) HvARRAY(hv);
1113 int longest_chain = 0;
1116 PERL_ARGS_ASSERT_HSPLIT;
1118 /*PerlIO_printf(PerlIO_stderr(), "hsplit called for %p which had %d\n",
1119 (void*)hv, (int) oldsize);*/
1121 if (HvPLACEHOLDERS_get(hv) && !SvREADONLY(hv)) {
1122 /* Can make this clear any placeholders first for non-restricted hashes,
1123 even though Storable rebuilds restricted hashes by putting in all the
1124 placeholders (first) before turning on the readonly flag, because
1125 Storable always pre-splits the hash. */
1126 hv_clear_placeholders(hv);
1130 #if defined(STRANGE_MALLOC) || defined(MYMALLOC)
1131 Renew(a, PERL_HV_ARRAY_ALLOC_BYTES(newsize)
1132 + (SvOOK(hv) ? sizeof(struct xpvhv_aux) : 0), char);
1138 Move(&a[oldsize * sizeof(HE*)], &a[newsize * sizeof(HE*)], 1, struct xpvhv_aux);
1141 Newx(a, PERL_HV_ARRAY_ALLOC_BYTES(newsize)
1142 + (SvOOK(hv) ? sizeof(struct xpvhv_aux) : 0), char);
1147 Copy(HvARRAY(hv), a, oldsize * sizeof(HE*), char);
1149 Copy(HvAUX(hv), &a[newsize * sizeof(HE*)], 1, struct xpvhv_aux);
1151 Safefree(HvARRAY(hv));
1155 Zero(&a[oldsize * sizeof(HE*)], (newsize-oldsize) * sizeof(HE*), char); /* zero 2nd half*/
1156 xhv->xhv_max = --newsize; /* HvMAX(hv) = --newsize */
1157 HvARRAY(hv) = (HE**) a;
1160 for (i=0; i<oldsize; i++,aep++) {
1161 int left_length = 0;
1162 int right_length = 0;
1167 if (!entry) /* non-existent */
1171 if ((HeHASH(entry) & newsize) != (U32)i) {
1172 *oentry = HeNEXT(entry);
1173 HeNEXT(entry) = *bep;
1178 oentry = &HeNEXT(entry);
1183 /* I think we don't actually need to keep track of the longest length,
1184 merely flag if anything is too long. But for the moment while
1185 developing this code I'll track it. */
1186 if (left_length > longest_chain)
1187 longest_chain = left_length;
1188 if (right_length > longest_chain)
1189 longest_chain = right_length;
1193 /* Pick your policy for "hashing isn't working" here: */
1194 if (longest_chain <= HV_MAX_LENGTH_BEFORE_SPLIT /* split worked? */
1199 if (hv == PL_strtab) {
1200 /* Urg. Someone is doing something nasty to the string table.
1205 /* Awooga. Awooga. Pathological data. */
1206 /*PerlIO_printf(PerlIO_stderr(), "%p %d of %d with %d/%d buckets\n", (void*)hv,
1207 longest_chain, HvTOTALKEYS(hv), HvFILL(hv), 1+HvMAX(hv));*/
1210 Newxz(a, PERL_HV_ARRAY_ALLOC_BYTES(newsize)
1211 + (SvOOK(hv) ? sizeof(struct xpvhv_aux) : 0), char);
1213 Copy(HvAUX(hv), &a[newsize * sizeof(HE*)], 1, struct xpvhv_aux);
1216 was_shared = HvSHAREKEYS(hv);
1218 HvSHAREKEYS_off(hv);
1223 for (i=0; i<newsize; i++,aep++) {
1224 register HE *entry = *aep;
1226 /* We're going to trash this HE's next pointer when we chain it
1227 into the new hash below, so store where we go next. */
1228 HE * const next = HeNEXT(entry);
1233 PERL_HASH_INTERNAL(hash, HeKEY(entry), HeKLEN(entry));
1238 = save_hek_flags(HeKEY(entry), HeKLEN(entry),
1239 hash, HeKFLAGS(entry));
1240 unshare_hek (HeKEY_hek(entry));
1241 HeKEY_hek(entry) = new_hek;
1243 /* Not shared, so simply write the new hash in. */
1244 HeHASH(entry) = hash;
1246 /*PerlIO_printf(PerlIO_stderr(), "%d ", HeKFLAGS(entry));*/
1247 HEK_REHASH_on(HeKEY_hek(entry));
1248 /*PerlIO_printf(PerlIO_stderr(), "%d\n", HeKFLAGS(entry));*/
1250 /* Copy oentry to the correct new chain. */
1251 bep = ((HE**)a) + (hash & (I32) xhv->xhv_max);
1252 HeNEXT(entry) = *bep;
1258 Safefree (HvARRAY(hv));
1259 HvARRAY(hv) = (HE **)a;
1263 Perl_hv_ksplit(pTHX_ HV *hv, IV newmax)
1266 register XPVHV* xhv = (XPVHV*)SvANY(hv);
1267 const I32 oldsize = (I32) xhv->xhv_max+1; /* HvMAX(hv)+1 (sick) */
1268 register I32 newsize;
1273 PERL_ARGS_ASSERT_HV_KSPLIT;
1275 newsize = (I32) newmax; /* possible truncation here */
1276 if (newsize != newmax || newmax <= oldsize)
1278 while ((newsize & (1 + ~newsize)) != newsize) {
1279 newsize &= ~(newsize & (1 + ~newsize)); /* get proper power of 2 */
1281 if (newsize < newmax)
1283 if (newsize < newmax)
1284 return; /* overflow detection */
1286 a = (char *) HvARRAY(hv);
1289 #if defined(STRANGE_MALLOC) || defined(MYMALLOC)
1290 Renew(a, PERL_HV_ARRAY_ALLOC_BYTES(newsize)
1291 + (SvOOK(hv) ? sizeof(struct xpvhv_aux) : 0), char);
1297 Copy(&a[oldsize * sizeof(HE*)], &a[newsize * sizeof(HE*)], 1, struct xpvhv_aux);
1300 Newx(a, PERL_HV_ARRAY_ALLOC_BYTES(newsize)
1301 + (SvOOK(hv) ? sizeof(struct xpvhv_aux) : 0), char);
1306 Copy(HvARRAY(hv), a, oldsize * sizeof(HE*), char);
1308 Copy(HvAUX(hv), &a[newsize * sizeof(HE*)], 1, struct xpvhv_aux);
1310 Safefree(HvARRAY(hv));
1313 Zero(&a[oldsize * sizeof(HE*)], (newsize-oldsize) * sizeof(HE*), char); /* zero 2nd half*/
1316 Newxz(a, PERL_HV_ARRAY_ALLOC_BYTES(newsize), char);
1318 xhv->xhv_max = --newsize; /* HvMAX(hv) = --newsize */
1319 HvARRAY(hv) = (HE **) a;
1320 if (!xhv->xhv_keys /* !HvTOTALKEYS(hv) */) /* skip rest if no entries */
1324 for (i=0; i<oldsize; i++,aep++) {
1328 if (!entry) /* non-existent */
1331 register I32 j = (HeHASH(entry) & newsize);
1335 *oentry = HeNEXT(entry);
1336 HeNEXT(entry) = aep[j];
1340 oentry = &HeNEXT(entry);
1347 Perl_newHVhv(pTHX_ HV *ohv)
1350 HV * const hv = newHV();
1353 if (!ohv || !HvTOTALKEYS(ohv))
1355 hv_max = HvMAX(ohv);
1357 if (!SvMAGICAL((const SV *)ohv)) {
1358 /* It's an ordinary hash, so copy it fast. AMS 20010804 */
1360 const bool shared = !!HvSHAREKEYS(ohv);
1361 HE **ents, ** const oents = (HE **)HvARRAY(ohv);
1363 Newx(a, PERL_HV_ARRAY_ALLOC_BYTES(hv_max+1), char);
1366 /* In each bucket... */
1367 for (i = 0; i <= hv_max; i++) {
1369 HE *oent = oents[i];
1376 /* Copy the linked list of entries. */
1377 for (; oent; oent = HeNEXT(oent)) {
1378 const U32 hash = HeHASH(oent);
1379 const char * const key = HeKEY(oent);
1380 const STRLEN len = HeKLEN(oent);
1381 const int flags = HeKFLAGS(oent);
1382 HE * const ent = new_HE();
1383 SV *const val = HeVAL(oent);
1385 HeVAL(ent) = SvIMMORTAL(val) ? val : newSVsv(val);
1387 = shared ? share_hek_flags(key, len, hash, flags)
1388 : save_hek_flags(key, len, hash, flags);
1399 HvTOTALKEYS(hv) = HvTOTALKEYS(ohv);
1403 /* Iterate over ohv, copying keys and values one at a time. */
1405 const I32 riter = HvRITER_get(ohv);
1406 HE * const eiter = HvEITER_get(ohv);
1407 STRLEN hv_fill = HvFILL(ohv);
1409 /* Can we use fewer buckets? (hv_max is always 2^n-1) */
1410 while (hv_max && hv_max + 1 >= hv_fill * 2)
1411 hv_max = hv_max / 2;
1415 while ((entry = hv_iternext_flags(ohv, 0))) {
1416 SV *const val = HeVAL(entry);
1417 (void)hv_store_flags(hv, HeKEY(entry), HeKLEN(entry),
1418 SvIMMORTAL(val) ? val : newSVsv(val),
1419 HeHASH(entry), HeKFLAGS(entry));
1421 HvRITER_set(ohv, riter);
1422 HvEITER_set(ohv, eiter);
1429 =for apidoc Am|HV *|hv_copy_hints_hv|HV *ohv
1431 A specialised version of L</newHVhv> for copying C<%^H>. I<ohv> must be
1432 a pointer to a hash (which may have C<%^H> magic, but should be generally
1433 non-magical), or C<NULL> (interpreted as an empty hash). The content
1434 of I<ohv> is copied to a new hash, which has the C<%^H>-specific magic
1435 added to it. A pointer to the new hash is returned.
1441 Perl_hv_copy_hints_hv(pTHX_ HV *const ohv)
1443 HV * const hv = newHV();
1445 if (ohv && HvTOTALKEYS(ohv)) {
1446 STRLEN hv_max = HvMAX(ohv);
1447 STRLEN hv_fill = HvFILL(ohv);
1449 const I32 riter = HvRITER_get(ohv);
1450 HE * const eiter = HvEITER_get(ohv);
1452 while (hv_max && hv_max + 1 >= hv_fill * 2)
1453 hv_max = hv_max / 2;
1457 while ((entry = hv_iternext_flags(ohv, 0))) {
1458 SV *const sv = newSVsv(HeVAL(entry));
1459 SV *heksv = newSVhek(HeKEY_hek(entry));
1460 sv_magic(sv, NULL, PERL_MAGIC_hintselem,
1461 (char *)heksv, HEf_SVKEY);
1462 SvREFCNT_dec(heksv);
1463 (void)hv_store_flags(hv, HeKEY(entry), HeKLEN(entry),
1464 sv, HeHASH(entry), HeKFLAGS(entry));
1466 HvRITER_set(ohv, riter);
1467 HvEITER_set(ohv, eiter);
1469 hv_magic(hv, NULL, PERL_MAGIC_hints);
1474 Perl_hv_free_ent(pTHX_ HV *hv, register HE *entry)
1479 PERL_ARGS_ASSERT_HV_FREE_ENT;
1484 if (val && isGV(val) && isGV_with_GP(val) && GvCVu(val) && HvENAME(hv))
1485 mro_method_changed_in(hv); /* deletion of method from stash */
1487 if (HeKLEN(entry) == HEf_SVKEY) {
1488 SvREFCNT_dec(HeKEY_sv(entry));
1489 Safefree(HeKEY_hek(entry));
1491 else if (HvSHAREKEYS(hv))
1492 unshare_hek(HeKEY_hek(entry));
1494 Safefree(HeKEY_hek(entry));
1500 Perl_hv_delayfree_ent(pTHX_ HV *hv, register HE *entry)
1504 PERL_ARGS_ASSERT_HV_DELAYFREE_ENT;
1508 /* SvREFCNT_inc to counter the SvREFCNT_dec in hv_free_ent */
1509 sv_2mortal(SvREFCNT_inc(HeVAL(entry))); /* free between statements */
1510 if (HeKLEN(entry) == HEf_SVKEY) {
1511 sv_2mortal(SvREFCNT_inc(HeKEY_sv(entry)));
1513 hv_free_ent(hv, entry);
1517 =for apidoc hv_clear
1519 Clears a hash, making it empty.
1525 Perl_hv_clear(pTHX_ HV *hv)
1528 register XPVHV* xhv;
1532 DEBUG_A(Perl_hv_assert(aTHX_ hv));
1534 xhv = (XPVHV*)SvANY(hv);
1536 if (SvREADONLY(hv) && HvARRAY(hv) != NULL) {
1537 /* restricted hash: convert all keys to placeholders */
1539 for (i = 0; i <= xhv->xhv_max; i++) {
1540 HE *entry = (HvARRAY(hv))[i];
1541 for (; entry; entry = HeNEXT(entry)) {
1542 /* not already placeholder */
1543 if (HeVAL(entry) != &PL_sv_placeholder) {
1544 if (HeVAL(entry) && SvREADONLY(HeVAL(entry))) {
1545 SV* const keysv = hv_iterkeysv(entry);
1547 "Attempt to delete readonly key '%"SVf"' from a restricted hash",
1550 SvREFCNT_dec(HeVAL(entry));
1551 HeVAL(entry) = &PL_sv_placeholder;
1552 HvPLACEHOLDERS(hv)++;
1560 HvPLACEHOLDERS_set(hv, 0);
1562 Zero(HvARRAY(hv), xhv->xhv_max+1 /* HvMAX(hv)+1 */, HE*);
1565 mg_clear(MUTABLE_SV(hv));
1567 HvHASKFLAGS_off(hv);
1572 mro_isa_changed_in(hv);
1573 HvEITER_set(hv, NULL);
1578 =for apidoc hv_clear_placeholders
1580 Clears any placeholders from a hash. If a restricted hash has any of its keys
1581 marked as readonly and the key is subsequently deleted, the key is not actually
1582 deleted but is marked by assigning it a value of &PL_sv_placeholder. This tags
1583 it so it will be ignored by future operations such as iterating over the hash,
1584 but will still allow the hash to have a value reassigned to the key at some
1585 future point. This function clears any such placeholder keys from the hash.
1586 See Hash::Util::lock_keys() for an example of its use.
1592 Perl_hv_clear_placeholders(pTHX_ HV *hv)
1595 const U32 items = (U32)HvPLACEHOLDERS_get(hv);
1597 PERL_ARGS_ASSERT_HV_CLEAR_PLACEHOLDERS;
1600 clear_placeholders(hv, items);
1604 S_clear_placeholders(pTHX_ HV *hv, U32 items)
1609 PERL_ARGS_ASSERT_CLEAR_PLACEHOLDERS;
1616 /* Loop down the linked list heads */
1618 HE **oentry = &(HvARRAY(hv))[i];
1621 while ((entry = *oentry)) {
1622 if (HeVAL(entry) == &PL_sv_placeholder) {
1623 *oentry = HeNEXT(entry);
1624 if (entry == HvEITER_get(hv))
1627 hv_free_ent(hv, entry);
1631 HvTOTALKEYS(hv) -= (IV)HvPLACEHOLDERS_get(hv);
1632 if (HvKEYS(hv) == 0)
1633 HvHASKFLAGS_off(hv);
1634 HvPLACEHOLDERS_set(hv, 0);
1638 oentry = &HeNEXT(entry);
1643 /* You can't get here, hence assertion should always fail. */
1644 assert (items == 0);
1649 S_hfreeentries(pTHX_ HV *hv)
1651 /* This is the array that we're going to restore */
1652 HE **const orig_array = HvARRAY(hv);
1657 PERL_ARGS_ASSERT_HFREEENTRIES;
1663 /* If the hash is actually a symbol table with a name, look after the
1665 struct xpvhv_aux *iter = HvAUX(hv);
1667 name = iter->xhv_name;
1668 name_count = iter->xhv_name_count;
1669 iter->xhv_name = NULL;
1675 /* orig_array remains unchanged throughout the loop. If after freeing all
1676 the entries it turns out that one of the little blighters has triggered
1677 an action that has caused HvARRAY to be re-allocated, then we set
1678 array to the new HvARRAY, and try again. */
1681 /* This is the one we're going to try to empty. First time round
1682 it's the original array. (Hopefully there will only be 1 time
1684 HE ** const array = HvARRAY(hv);
1687 /* Because we have taken xhv_name out, the only allocated pointer
1688 in the aux structure that might exist is the backreference array.
1693 struct mro_meta *meta;
1694 struct xpvhv_aux *iter = HvAUX(hv);
1695 /* weak references: if called from sv_clear(), the backrefs
1696 * should already have been killed; if there are any left, its
1697 * because we're doing hv_clear() or hv_undef(), and the HV
1698 * will continue to live.
1699 * Because while freeing the entries we fake up a NULL HvARRAY
1700 * (and hence HvAUX), we need to store the backref array
1701 * somewhere else; but it still needs to be visible in case
1702 * any the things we free happen to call sv_del_backref().
1703 * We do this by storing it in magic instead.
1704 * If, during the entry freeing, a destructor happens to add
1705 * a new weak backref, then sv_add_backref will look in both
1706 * places (magic in HvAUX) for the AV, but will create a new
1707 * AV in HvAUX if it can't find one (if it finds it in magic,
1708 * it moves it back into HvAUX. So at the end of the iteration
1709 * we have to allow for this. */
1712 if (iter->xhv_backreferences) {
1713 if (SvTYPE(iter->xhv_backreferences) == SVt_PVAV) {
1714 /* The sv_magic will increase the reference count of the AV,
1715 so we need to drop it first. */
1716 SvREFCNT_dec(iter->xhv_backreferences);
1717 if (AvFILLp(iter->xhv_backreferences) == -1) {
1718 /* Turns out that the array is empty. Just free it. */
1719 SvREFCNT_dec(iter->xhv_backreferences);
1722 sv_magic(MUTABLE_SV(hv),
1723 MUTABLE_SV(iter->xhv_backreferences),
1724 PERL_MAGIC_backref, NULL, 0);
1729 sv_magic(MUTABLE_SV(hv), NULL, PERL_MAGIC_backref, NULL, 0);
1730 mg = mg_find(MUTABLE_SV(hv), PERL_MAGIC_backref);
1731 mg->mg_obj = (SV*)iter->xhv_backreferences;
1733 iter->xhv_backreferences = NULL;
1736 entry = iter->xhv_eiter; /* HvEITER(hv) */
1737 if (entry && HvLAZYDEL(hv)) { /* was deleted earlier? */
1739 hv_free_ent(hv, entry);
1741 iter->xhv_riter = -1; /* HvRITER(hv) = -1 */
1742 iter->xhv_eiter = NULL; /* HvEITER(hv) = NULL */
1744 if((meta = iter->xhv_mro_meta)) {
1745 if (meta->mro_linear_all) {
1746 SvREFCNT_dec(MUTABLE_SV(meta->mro_linear_all));
1747 meta->mro_linear_all = NULL;
1748 /* This is just acting as a shortcut pointer. */
1749 meta->mro_linear_current = NULL;
1750 } else if (meta->mro_linear_current) {
1751 /* Only the current MRO is stored, so this owns the data.
1753 SvREFCNT_dec(meta->mro_linear_current);
1754 meta->mro_linear_current = NULL;
1756 if(meta->mro_nextmethod) SvREFCNT_dec(meta->mro_nextmethod);
1757 SvREFCNT_dec(meta->isa);
1759 iter->xhv_mro_meta = NULL;
1762 /* There are now no allocated pointers in the aux structure. */
1764 SvFLAGS(hv) &= ~SVf_OOK; /* Goodbye, aux structure. */
1765 /* What aux structure? */
1768 /* make everyone else think the array is empty, so that the destructors
1769 * called for freed entries can't recursively mess with us */
1771 ((XPVHV*) SvANY(hv))->xhv_keys = 0;
1775 /* Loop down the linked list heads */
1776 HE *entry = array[i];
1779 register HE * const oentry = entry;
1780 entry = HeNEXT(entry);
1781 hv_free_ent(hv, oentry);
1785 /* As there are no allocated pointers in the aux structure, it's now
1786 safe to free the array we just cleaned up, if it's not the one we're
1787 going to put back. */
1788 if (array != orig_array) {
1793 /* Good. No-one added anything this time round. */
1798 /* Someone attempted to iterate or set the hash name while we had
1799 the array set to 0. We'll catch backferences on the next time
1800 round the while loop. */
1801 assert(HvARRAY(hv));
1803 if (HvAUX(hv)->xhv_name) {
1804 if(HvAUX(hv)->xhv_name_count) {
1805 HEK ** const name = (HEK **)HvAUX(hv)->xhv_name;
1806 I32 const count = HvAUX(hv)->xhv_name_count;
1807 HEK **hekp = name + (count < 0 ? -count : count);
1808 while(hekp-- > name)
1809 unshare_hek_or_pvn(*hekp, 0, 0, 0);
1812 else unshare_hek_or_pvn(HvAUX(hv)->xhv_name, 0, 0, 0);
1816 if (--attempts == 0) {
1817 Perl_die(aTHX_ "panic: hfreeentries failed to free hash - something is repeatedly re-creating entries");
1821 HvARRAY(hv) = orig_array;
1823 /* If the hash was actually a symbol table, put the name back. */
1825 /* We have restored the original array. If name is non-NULL, then
1826 the original array had an aux structure at the end. So this is
1828 struct xpvhv_aux * const aux = HvAUX(hv);
1829 SvFLAGS(hv) |= SVf_OOK;
1830 aux->xhv_name = name;
1831 aux->xhv_name_count = name_count;
1836 =for apidoc hv_undef
1844 Perl_hv_undef(pTHX_ HV *hv)
1847 register XPVHV* xhv;
1852 DEBUG_A(Perl_hv_assert(aTHX_ hv));
1853 xhv = (XPVHV*)SvANY(hv);
1855 if ((name = HvENAME_get(hv)) && !PL_dirty)
1856 mro_isa_changed_in(hv);
1859 if (name || (name = HvNAME(hv))) {
1861 (void)hv_delete(PL_stashcache, name, HvNAMELEN_get(hv), G_DISCARD);
1862 hv_name_set(hv, NULL, 0, 0);
1864 SvFLAGS(hv) &= ~SVf_OOK;
1865 Safefree(HvARRAY(hv));
1866 xhv->xhv_max = 7; /* HvMAX(hv) = 7 (it's a normal hash) */
1868 HvPLACEHOLDERS_set(hv, 0);
1871 mg_clear(MUTABLE_SV(hv));
1877 Returns the number of hash buckets that happen to be in use. This function is
1878 wrapped by the macro C<HvFILL>.
1880 Previously this value was stored in the HV structure, rather than being
1881 calculated on demand.
1887 Perl_hv_fill(pTHX_ HV const *const hv)
1890 HE **ents = HvARRAY(hv);
1892 PERL_ARGS_ASSERT_HV_FILL;
1895 HE *const *const last = ents + HvMAX(hv);
1896 count = last + 1 - ents;
1901 } while (++ents <= last);
1906 static struct xpvhv_aux*
1907 S_hv_auxinit(HV *hv) {
1908 struct xpvhv_aux *iter;
1911 PERL_ARGS_ASSERT_HV_AUXINIT;
1914 Newxz(array, PERL_HV_ARRAY_ALLOC_BYTES(HvMAX(hv) + 1)
1915 + sizeof(struct xpvhv_aux), char);
1917 array = (char *) HvARRAY(hv);
1918 Renew(array, PERL_HV_ARRAY_ALLOC_BYTES(HvMAX(hv) + 1)
1919 + sizeof(struct xpvhv_aux), char);
1921 HvARRAY(hv) = (HE**) array;
1922 /* SvOOK_on(hv) attacks the IV flags. */
1923 SvFLAGS(hv) |= SVf_OOK;
1926 iter->xhv_riter = -1; /* HvRITER(hv) = -1 */
1927 iter->xhv_eiter = NULL; /* HvEITER(hv) = NULL */
1929 iter->xhv_name_count = 0;
1930 iter->xhv_backreferences = 0;
1931 iter->xhv_mro_meta = NULL;
1936 =for apidoc hv_iterinit
1938 Prepares a starting point to traverse a hash table. Returns the number of
1939 keys in the hash (i.e. the same as C<HvKEYS(hv)>). The return value is
1940 currently only meaningful for hashes without tie magic.
1942 NOTE: Before version 5.004_65, C<hv_iterinit> used to return the number of
1943 hash buckets that happen to be in use. If you still need that esoteric
1944 value, you can get it through the macro C<HvFILL(hv)>.
1951 Perl_hv_iterinit(pTHX_ HV *hv)
1953 PERL_ARGS_ASSERT_HV_ITERINIT;
1955 /* FIXME: Are we not NULL, or do we croak? Place bets now! */
1958 Perl_croak(aTHX_ "Bad hash");
1961 struct xpvhv_aux * const iter = HvAUX(hv);
1962 HE * const entry = iter->xhv_eiter; /* HvEITER(hv) */
1963 if (entry && HvLAZYDEL(hv)) { /* was deleted earlier? */
1965 hv_free_ent(hv, entry);
1967 iter->xhv_riter = -1; /* HvRITER(hv) = -1 */
1968 iter->xhv_eiter = NULL; /* HvEITER(hv) = NULL */
1973 /* used to be xhv->xhv_fill before 5.004_65 */
1974 return HvTOTALKEYS(hv);
1978 Perl_hv_riter_p(pTHX_ HV *hv) {
1979 struct xpvhv_aux *iter;
1981 PERL_ARGS_ASSERT_HV_RITER_P;
1984 Perl_croak(aTHX_ "Bad hash");
1986 iter = SvOOK(hv) ? HvAUX(hv) : hv_auxinit(hv);
1987 return &(iter->xhv_riter);
1991 Perl_hv_eiter_p(pTHX_ HV *hv) {
1992 struct xpvhv_aux *iter;
1994 PERL_ARGS_ASSERT_HV_EITER_P;
1997 Perl_croak(aTHX_ "Bad hash");
1999 iter = SvOOK(hv) ? HvAUX(hv) : hv_auxinit(hv);
2000 return &(iter->xhv_eiter);
2004 Perl_hv_riter_set(pTHX_ HV *hv, I32 riter) {
2005 struct xpvhv_aux *iter;
2007 PERL_ARGS_ASSERT_HV_RITER_SET;
2010 Perl_croak(aTHX_ "Bad hash");
2018 iter = hv_auxinit(hv);
2020 iter->xhv_riter = riter;
2024 Perl_hv_eiter_set(pTHX_ HV *hv, HE *eiter) {
2025 struct xpvhv_aux *iter;
2027 PERL_ARGS_ASSERT_HV_EITER_SET;
2030 Perl_croak(aTHX_ "Bad hash");
2035 /* 0 is the default so don't go malloc()ing a new structure just to
2040 iter = hv_auxinit(hv);
2042 iter->xhv_eiter = eiter;
2046 Perl_hv_name_set(pTHX_ HV *hv, const char *name, U32 len, U32 flags)
2049 struct xpvhv_aux *iter;
2053 PERL_ARGS_ASSERT_HV_NAME_SET;
2054 PERL_UNUSED_ARG(flags);
2057 Perl_croak(aTHX_ "panic: hv name too long (%"UVuf")", (UV) len);
2061 if (iter->xhv_name) {
2062 if(iter->xhv_name_count) {
2064 HEK ** const name = (HEK **)HvAUX(hv)->xhv_name;
2065 HEK **hekp = name + (
2066 iter->xhv_name_count < 0
2067 ? -iter->xhv_name_count
2068 : iter->xhv_name_count
2070 while(hekp-- > name+1)
2071 unshare_hek_or_pvn(*hekp, 0, 0, 0);
2072 /* The first elem may be null. */
2073 if(*name) unshare_hek_or_pvn(*name, 0, 0, 0);
2075 spot = &iter->xhv_name;
2076 iter->xhv_name_count = 0;
2079 spot = (HEK **)iter->xhv_name;
2080 if(iter->xhv_name_count > 0) {
2081 /* shift some things over */
2082 Renew(spot, iter->xhv_name_count, HEK *);
2083 spot[iter->xhv_name_count++] = spot[1];
2087 unshare_hek_or_pvn(*spot, 0, 0, 0);
2092 unshare_hek_or_pvn(iter->xhv_name, 0, 0, 0);
2093 spot = &iter->xhv_name;
2096 else spot = &iter->xhv_name;
2101 iter = hv_auxinit(hv);
2102 spot = &iter->xhv_name;
2104 PERL_HASH(hash, name, len);
2105 *spot = name ? share_hek(name, len, hash) : NULL;
2106 iter->xhv_name_count = 0;
2110 =for apidoc hv_ename_add
2112 Adds a name to a stash's internal list of effective names. See
2115 This is called when a stash is assigned to a new location in the symbol
2122 Perl_hv_ename_add(pTHX_ HV *hv, const char *name, U32 len)
2125 struct xpvhv_aux *aux = SvOOK(hv) ? HvAUX(hv) : hv_auxinit(hv);
2128 PERL_ARGS_ASSERT_HV_ENAME_ADD;
2131 Perl_croak(aTHX_ "panic: hv name too long (%"UVuf")", (UV) len);
2133 PERL_HASH(hash, name, len);
2135 if (aux->xhv_name_count) {
2136 HEK ** const xhv_name = (HEK **)aux->xhv_name;
2137 I32 count = aux->xhv_name_count;
2138 HEK **hekp = xhv_name + (count < 0 ? -count : count);
2139 while (hekp-- > xhv_name)
2141 HEK_LEN(*hekp) == (I32)len && memEQ(HEK_KEY(*hekp), name, len)
2143 if (hekp == xhv_name && count < 0)
2144 aux->xhv_name_count = -count;
2147 if (count < 0) aux->xhv_name_count--, count = -count;
2148 else aux->xhv_name_count++;
2149 Renewc(aux->xhv_name, count + 1, HEK *, HEK);
2150 ((HEK **)aux->xhv_name)[count] = share_hek(name, len, hash);
2153 HEK *existing_name = aux->xhv_name;
2155 existing_name && HEK_LEN(existing_name) == (I32)len
2156 && memEQ(HEK_KEY(existing_name), name, len)
2158 Newxc(aux->xhv_name, 2, HEK *, HEK);
2159 aux->xhv_name_count = existing_name ? 2 : -2;
2160 *(HEK **)aux->xhv_name = existing_name;
2161 ((HEK **)aux->xhv_name)[1] = share_hek(name, len, hash);
2166 =for apidoc hv_ename_delete
2168 Removes a name from a stash's internal list of effective names. If this is
2169 the name returned by C<HvENAME>, then another name in the list will take
2170 its place (C<HvENAME> will use it).
2172 This is called when a stash is deleted from the symbol table.
2178 Perl_hv_ename_delete(pTHX_ HV *hv, const char *name, U32 len)
2181 struct xpvhv_aux *aux;
2183 PERL_ARGS_ASSERT_HV_ENAME_DELETE;
2186 Perl_croak(aTHX_ "panic: hv name too long (%"UVuf")", (UV) len);
2188 if (!SvOOK(hv)) return;
2191 if (!aux->xhv_name) return;
2193 if (aux->xhv_name_count) {
2194 HEK ** const namep = (HEK **)aux->xhv_name;
2195 I32 const count = aux->xhv_name_count;
2196 HEK **victim = namep + (count < 0 ? -count : count);
2197 while (victim-- > namep + 1)
2199 HEK_LEN(*victim) == (I32)len
2200 && memEQ(HEK_KEY(*victim), name, len)
2202 unshare_hek_or_pvn(*victim, 0, 0, 0);
2203 if (count < 0) ++aux->xhv_name_count;
2204 else --aux->xhv_name_count;
2206 (aux->xhv_name_count == 1 || aux->xhv_name_count == -1)
2208 ) { /* if there are none left */
2210 aux->xhv_name = NULL;
2211 aux->xhv_name_count = 0;
2214 /* Move the last one back to fill the empty slot. It
2215 does not matter what order they are in. */
2216 *victim = *(namep + (count < 0 ? -count : count) - 1);
2221 count > 0 && HEK_LEN(*namep) == (I32)len
2222 && memEQ(HEK_KEY(*namep),name,len)
2224 aux->xhv_name_count = -count;
2228 HEK_LEN(aux->xhv_name) == (I32)len
2229 && memEQ(HEK_KEY(aux->xhv_name), name, len)
2231 const HEK * const namehek = aux->xhv_name;
2232 Newxc(aux->xhv_name, 1, HEK *, HEK);
2233 *(const HEK **)aux->xhv_name = namehek;
2234 aux->xhv_name_count = -1;
2239 Perl_hv_backreferences_p(pTHX_ HV *hv) {
2240 struct xpvhv_aux * const iter = SvOOK(hv) ? HvAUX(hv) : hv_auxinit(hv);
2242 PERL_ARGS_ASSERT_HV_BACKREFERENCES_P;
2243 PERL_UNUSED_CONTEXT;
2245 return &(iter->xhv_backreferences);
2249 Perl_hv_kill_backrefs(pTHX_ HV *hv) {
2252 PERL_ARGS_ASSERT_HV_KILL_BACKREFS;
2257 av = HvAUX(hv)->xhv_backreferences;
2260 HvAUX(hv)->xhv_backreferences = 0;
2261 Perl_sv_kill_backrefs(aTHX_ MUTABLE_SV(hv), av);
2262 if (SvTYPE(av) == SVt_PVAV)
2268 hv_iternext is implemented as a macro in hv.h
2270 =for apidoc hv_iternext
2272 Returns entries from a hash iterator. See C<hv_iterinit>.
2274 You may call C<hv_delete> or C<hv_delete_ent> on the hash entry that the
2275 iterator currently points to, without losing your place or invalidating your
2276 iterator. Note that in this case the current entry is deleted from the hash
2277 with your iterator holding the last reference to it. Your iterator is flagged
2278 to free the entry on the next call to C<hv_iternext>, so you must not discard
2279 your iterator immediately else the entry will leak - call C<hv_iternext> to
2280 trigger the resource deallocation.
2282 =for apidoc hv_iternext_flags
2284 Returns entries from a hash iterator. See C<hv_iterinit> and C<hv_iternext>.
2285 The C<flags> value will normally be zero; if HV_ITERNEXT_WANTPLACEHOLDERS is
2286 set the placeholders keys (for restricted hashes) will be returned in addition
2287 to normal keys. By default placeholders are automatically skipped over.
2288 Currently a placeholder is implemented with a value that is
2289 C<&Perl_sv_placeholder>. Note that the implementation of placeholders and
2290 restricted hashes may change, and the implementation currently is
2291 insufficiently abstracted for any change to be tidy.
2297 Perl_hv_iternext_flags(pTHX_ HV *hv, I32 flags)
2300 register XPVHV* xhv;
2304 struct xpvhv_aux *iter;
2306 PERL_ARGS_ASSERT_HV_ITERNEXT_FLAGS;
2309 Perl_croak(aTHX_ "Bad hash");
2311 xhv = (XPVHV*)SvANY(hv);
2314 /* Too many things (well, pp_each at least) merrily assume that you can
2315 call iv_iternext without calling hv_iterinit, so we'll have to deal
2321 oldentry = entry = iter->xhv_eiter; /* HvEITER(hv) */
2322 if (SvMAGICAL(hv) && SvRMAGICAL(hv)) {
2323 if ( ( mg = mg_find((const SV *)hv, PERL_MAGIC_tied) ) ) {
2324 SV * const key = sv_newmortal();
2326 sv_setsv(key, HeSVKEY_force(entry));
2327 SvREFCNT_dec(HeSVKEY(entry)); /* get rid of previous key */
2333 /* one HE per MAGICAL hash */
2334 iter->xhv_eiter = entry = new_HE(); /* HvEITER(hv) = new_HE() */
2336 Newxz(k, HEK_BASESIZE + sizeof(const SV *), char);
2338 HeKEY_hek(entry) = hek;
2339 HeKLEN(entry) = HEf_SVKEY;
2341 magic_nextpack(MUTABLE_SV(hv),mg,key);
2343 /* force key to stay around until next time */
2344 HeSVKEY_set(entry, SvREFCNT_inc_simple_NN(key));
2345 return entry; /* beware, hent_val is not set */
2347 SvREFCNT_dec(HeVAL(entry));
2348 Safefree(HeKEY_hek(entry));
2350 iter->xhv_eiter = NULL; /* HvEITER(hv) = NULL */
2354 #if defined(DYNAMIC_ENV_FETCH) && !defined(__riscos__) /* set up %ENV for iteration */
2355 if (!entry && SvRMAGICAL((const SV *)hv)
2356 && mg_find((const SV *)hv, PERL_MAGIC_env)) {
2359 /* The prime_env_iter() on VMS just loaded up new hash values
2360 * so the iteration count needs to be reset back to the beginning
2364 oldentry = entry = iter->xhv_eiter; /* HvEITER(hv) */
2369 /* hv_iterint now ensures this. */
2370 assert (HvARRAY(hv));
2372 /* At start of hash, entry is NULL. */
2375 entry = HeNEXT(entry);
2376 if (!(flags & HV_ITERNEXT_WANTPLACEHOLDERS)) {
2378 * Skip past any placeholders -- don't want to include them in
2381 while (entry && HeVAL(entry) == &PL_sv_placeholder) {
2382 entry = HeNEXT(entry);
2387 /* Skip the entire loop if the hash is empty. */
2388 if ((flags & HV_ITERNEXT_WANTPLACEHOLDERS)
2389 ? HvTOTALKEYS(hv) : HvUSEDKEYS(hv)) {
2391 /* OK. Come to the end of the current list. Grab the next one. */
2393 iter->xhv_riter++; /* HvRITER(hv)++ */
2394 if (iter->xhv_riter > (I32)xhv->xhv_max /* HvRITER(hv) > HvMAX(hv) */) {
2395 /* There is no next one. End of the hash. */
2396 iter->xhv_riter = -1; /* HvRITER(hv) = -1 */
2399 entry = (HvARRAY(hv))[iter->xhv_riter];
2401 if (!(flags & HV_ITERNEXT_WANTPLACEHOLDERS)) {
2402 /* If we have an entry, but it's a placeholder, don't count it.
2404 while (entry && HeVAL(entry) == &PL_sv_placeholder)
2405 entry = HeNEXT(entry);
2407 /* Will loop again if this linked list starts NULL
2408 (for HV_ITERNEXT_WANTPLACEHOLDERS)
2409 or if we run through it and find only placeholders. */
2413 if (oldentry && HvLAZYDEL(hv)) { /* was deleted earlier? */
2415 hv_free_ent(hv, oldentry);
2418 /*if (HvREHASH(hv) && entry && !HeKREHASH(entry))
2419 PerlIO_printf(PerlIO_stderr(), "Awooga %p %p\n", (void*)hv, (void*)entry);*/
2421 iter->xhv_eiter = entry; /* HvEITER(hv) = entry */
2426 =for apidoc hv_iterkey
2428 Returns the key from the current position of the hash iterator. See
2435 Perl_hv_iterkey(pTHX_ register HE *entry, I32 *retlen)
2437 PERL_ARGS_ASSERT_HV_ITERKEY;
2439 if (HeKLEN(entry) == HEf_SVKEY) {
2441 char * const p = SvPV(HeKEY_sv(entry), len);
2446 *retlen = HeKLEN(entry);
2447 return HeKEY(entry);
2451 /* unlike hv_iterval(), this always returns a mortal copy of the key */
2453 =for apidoc hv_iterkeysv
2455 Returns the key as an C<SV*> from the current position of the hash
2456 iterator. The return value will always be a mortal copy of the key. Also
2463 Perl_hv_iterkeysv(pTHX_ register HE *entry)
2465 PERL_ARGS_ASSERT_HV_ITERKEYSV;
2467 return sv_2mortal(newSVhek(HeKEY_hek(entry)));
2471 =for apidoc hv_iterval
2473 Returns the value from the current position of the hash iterator. See
2480 Perl_hv_iterval(pTHX_ HV *hv, register HE *entry)
2482 PERL_ARGS_ASSERT_HV_ITERVAL;
2484 if (SvRMAGICAL(hv)) {
2485 if (mg_find((const SV *)hv, PERL_MAGIC_tied)) {
2486 SV* const sv = sv_newmortal();
2487 if (HeKLEN(entry) == HEf_SVKEY)
2488 mg_copy(MUTABLE_SV(hv), sv, (char*)HeKEY_sv(entry), HEf_SVKEY);
2490 mg_copy(MUTABLE_SV(hv), sv, HeKEY(entry), HeKLEN(entry));
2494 return HeVAL(entry);
2498 =for apidoc hv_iternextsv
2500 Performs an C<hv_iternext>, C<hv_iterkey>, and C<hv_iterval> in one
2507 Perl_hv_iternextsv(pTHX_ HV *hv, char **key, I32 *retlen)
2509 HE * const he = hv_iternext_flags(hv, 0);
2511 PERL_ARGS_ASSERT_HV_ITERNEXTSV;
2515 *key = hv_iterkey(he, retlen);
2516 return hv_iterval(hv, he);
2523 =for apidoc hv_magic
2525 Adds magic to a hash. See C<sv_magic>.
2530 /* possibly free a shared string if no one has access to it
2531 * len and hash must both be valid for str.
2534 Perl_unsharepvn(pTHX_ const char *str, I32 len, U32 hash)
2536 unshare_hek_or_pvn (NULL, str, len, hash);
2541 Perl_unshare_hek(pTHX_ HEK *hek)
2544 unshare_hek_or_pvn(hek, NULL, 0, 0);
2547 /* possibly free a shared string if no one has access to it
2548 hek if non-NULL takes priority over the other 3, else str, len and hash
2549 are used. If so, len and hash must both be valid for str.
2552 S_unshare_hek_or_pvn(pTHX_ const HEK *hek, const char *str, I32 len, U32 hash)
2555 register XPVHV* xhv;
2557 register HE **oentry;
2559 bool is_utf8 = FALSE;
2561 const char * const save = str;
2562 struct shared_he *he = NULL;
2565 /* Find the shared he which is just before us in memory. */
2566 he = (struct shared_he *)(((char *)hek)
2567 - STRUCT_OFFSET(struct shared_he,
2570 /* Assert that the caller passed us a genuine (or at least consistent)
2572 assert (he->shared_he_he.hent_hek == hek);
2574 if (he->shared_he_he.he_valu.hent_refcount - 1) {
2575 --he->shared_he_he.he_valu.hent_refcount;
2579 hash = HEK_HASH(hek);
2580 } else if (len < 0) {
2581 STRLEN tmplen = -len;
2583 /* See the note in hv_fetch(). --jhi */
2584 str = (char*)bytes_from_utf8((U8*)str, &tmplen, &is_utf8);
2587 k_flags = HVhek_UTF8;
2589 k_flags |= HVhek_WASUTF8 | HVhek_FREEKEY;
2592 /* what follows was the moral equivalent of:
2593 if ((Svp = hv_fetch(PL_strtab, tmpsv, FALSE, hash))) {
2595 hv_delete(PL_strtab, str, len, G_DISCARD, hash);
2597 xhv = (XPVHV*)SvANY(PL_strtab);
2598 /* assert(xhv_array != 0) */
2599 first = oentry = &(HvARRAY(PL_strtab))[hash & (I32) HvMAX(PL_strtab)];
2601 const HE *const he_he = &(he->shared_he_he);
2602 for (entry = *oentry; entry; oentry = &HeNEXT(entry), entry = *oentry) {
2607 const int flags_masked = k_flags & HVhek_MASK;
2608 for (entry = *oentry; entry; oentry = &HeNEXT(entry), entry = *oentry) {
2609 if (HeHASH(entry) != hash) /* strings can't be equal */
2611 if (HeKLEN(entry) != len)
2613 if (HeKEY(entry) != str && memNE(HeKEY(entry),str,len)) /* is this it? */
2615 if (HeKFLAGS(entry) != flags_masked)
2622 if (--entry->he_valu.hent_refcount == 0) {
2623 *oentry = HeNEXT(entry);
2625 xhv->xhv_keys--; /* HvTOTALKEYS(hv)-- */
2630 Perl_ck_warner_d(aTHX_ packWARN(WARN_INTERNAL),
2631 "Attempt to free non-existent shared string '%s'%s"
2633 hek ? HEK_KEY(hek) : str,
2634 ((k_flags & HVhek_UTF8) ? " (utf8)" : "") pTHX__VALUE);
2635 if (k_flags & HVhek_FREEKEY)
2639 /* get a (constant) string ptr from the global string table
2640 * string will get added if it is not already there.
2641 * len and hash must both be valid for str.
2644 Perl_share_hek(pTHX_ const char *str, I32 len, register U32 hash)
2646 bool is_utf8 = FALSE;
2648 const char * const save = str;
2650 PERL_ARGS_ASSERT_SHARE_HEK;
2653 STRLEN tmplen = -len;
2655 /* See the note in hv_fetch(). --jhi */
2656 str = (char*)bytes_from_utf8((U8*)str, &tmplen, &is_utf8);
2658 /* If we were able to downgrade here, then than means that we were passed
2659 in a key which only had chars 0-255, but was utf8 encoded. */
2662 /* If we found we were able to downgrade the string to bytes, then
2663 we should flag that it needs upgrading on keys or each. Also flag
2664 that we need share_hek_flags to free the string. */
2666 flags |= HVhek_WASUTF8 | HVhek_FREEKEY;
2669 return share_hek_flags (str, len, hash, flags);
2673 S_share_hek_flags(pTHX_ const char *str, I32 len, register U32 hash, int flags)
2677 const int flags_masked = flags & HVhek_MASK;
2678 const U32 hindex = hash & (I32) HvMAX(PL_strtab);
2679 register XPVHV * const xhv = (XPVHV*)SvANY(PL_strtab);
2681 PERL_ARGS_ASSERT_SHARE_HEK_FLAGS;
2683 /* what follows is the moral equivalent of:
2685 if (!(Svp = hv_fetch(PL_strtab, str, len, FALSE)))
2686 hv_store(PL_strtab, str, len, NULL, hash);
2688 Can't rehash the shared string table, so not sure if it's worth
2689 counting the number of entries in the linked list
2692 /* assert(xhv_array != 0) */
2693 entry = (HvARRAY(PL_strtab))[hindex];
2694 for (;entry; entry = HeNEXT(entry)) {
2695 if (HeHASH(entry) != hash) /* strings can't be equal */
2697 if (HeKLEN(entry) != len)
2699 if (HeKEY(entry) != str && memNE(HeKEY(entry),str,len)) /* is this it? */
2701 if (HeKFLAGS(entry) != flags_masked)
2707 /* What used to be head of the list.
2708 If this is NULL, then we're the first entry for this slot, which
2709 means we need to increate fill. */
2710 struct shared_he *new_entry;
2713 HE **const head = &HvARRAY(PL_strtab)[hindex];
2714 HE *const next = *head;
2716 /* We don't actually store a HE from the arena and a regular HEK.
2717 Instead we allocate one chunk of memory big enough for both,
2718 and put the HEK straight after the HE. This way we can find the
2719 HEK directly from the HE.
2722 Newx(k, STRUCT_OFFSET(struct shared_he,
2723 shared_he_hek.hek_key[0]) + len + 2, char);
2724 new_entry = (struct shared_he *)k;
2725 entry = &(new_entry->shared_he_he);
2726 hek = &(new_entry->shared_he_hek);
2728 Copy(str, HEK_KEY(hek), len, char);
2729 HEK_KEY(hek)[len] = 0;
2731 HEK_HASH(hek) = hash;
2732 HEK_FLAGS(hek) = (unsigned char)flags_masked;
2734 /* Still "point" to the HEK, so that other code need not know what
2736 HeKEY_hek(entry) = hek;
2737 entry->he_valu.hent_refcount = 0;
2738 HeNEXT(entry) = next;
2741 xhv->xhv_keys++; /* HvTOTALKEYS(hv)++ */
2742 if (!next) { /* initial entry? */
2743 } else if (xhv->xhv_keys > xhv->xhv_max /* HvKEYS(hv) > HvMAX(hv) */) {
2748 ++entry->he_valu.hent_refcount;
2750 if (flags & HVhek_FREEKEY)
2753 return HeKEY_hek(entry);
2757 Perl_hv_placeholders_p(pTHX_ HV *hv)
2760 MAGIC *mg = mg_find((const SV *)hv, PERL_MAGIC_rhash);
2762 PERL_ARGS_ASSERT_HV_PLACEHOLDERS_P;
2765 mg = sv_magicext(MUTABLE_SV(hv), 0, PERL_MAGIC_rhash, 0, 0, 0);
2768 Perl_die(aTHX_ "panic: hv_placeholders_p");
2771 return &(mg->mg_len);
2776 Perl_hv_placeholders_get(pTHX_ const HV *hv)
2779 MAGIC * const mg = mg_find((const SV *)hv, PERL_MAGIC_rhash);
2781 PERL_ARGS_ASSERT_HV_PLACEHOLDERS_GET;
2783 return mg ? mg->mg_len : 0;
2787 Perl_hv_placeholders_set(pTHX_ HV *hv, I32 ph)
2790 MAGIC * const mg = mg_find((const SV *)hv, PERL_MAGIC_rhash);
2792 PERL_ARGS_ASSERT_HV_PLACEHOLDERS_SET;
2797 if (!sv_magicext(MUTABLE_SV(hv), 0, PERL_MAGIC_rhash, 0, 0, ph))
2798 Perl_die(aTHX_ "panic: hv_placeholders_set");
2800 /* else we don't need to add magic to record 0 placeholders. */
2804 S_refcounted_he_value(pTHX_ const struct refcounted_he *he)
2809 PERL_ARGS_ASSERT_REFCOUNTED_HE_VALUE;
2811 switch(he->refcounted_he_data[0] & HVrhek_typemask) {
2816 value = &PL_sv_placeholder;
2819 value = newSViv(he->refcounted_he_val.refcounted_he_u_iv);
2822 value = newSVuv(he->refcounted_he_val.refcounted_he_u_uv);
2825 case HVrhek_PV_UTF8:
2826 /* Create a string SV that directly points to the bytes in our
2828 value = newSV_type(SVt_PV);
2829 SvPV_set(value, (char *) he->refcounted_he_data + 1);
2830 SvCUR_set(value, he->refcounted_he_val.refcounted_he_u_len);
2831 /* This stops anything trying to free it */
2832 SvLEN_set(value, 0);
2834 SvREADONLY_on(value);
2835 if ((he->refcounted_he_data[0] & HVrhek_typemask) == HVrhek_PV_UTF8)
2839 Perl_croak(aTHX_ "panic: refcounted_he_value bad flags %"UVxf,
2840 (UV)he->refcounted_he_data[0]);
2846 =for apidoc m|HV *|refcounted_he_chain_2hv|const struct refcounted_he *c|U32 flags
2848 Generates and returns a C<HV *> representing the content of a
2849 C<refcounted_he> chain.
2850 I<flags> is currently unused and must be zero.
2855 Perl_refcounted_he_chain_2hv(pTHX_ const struct refcounted_he *chain, U32 flags)
2859 U32 placeholders, max;
2862 Perl_croak(aTHX_ "panic: refcounted_he_chain_2hv bad flags %"UVxf,
2865 /* We could chase the chain once to get an idea of the number of keys,
2866 and call ksplit. But for now we'll make a potentially inefficient
2867 hash with only 8 entries in its array. */
2872 Newxz(array, PERL_HV_ARRAY_ALLOC_BYTES(max + 1), char);
2873 HvARRAY(hv) = (HE**)array;
2879 U32 hash = chain->refcounted_he_hash;
2881 U32 hash = HEK_HASH(chain->refcounted_he_hek);
2883 HE **oentry = &((HvARRAY(hv))[hash & max]);
2884 HE *entry = *oentry;
2887 for (; entry; entry = HeNEXT(entry)) {
2888 if (HeHASH(entry) == hash) {
2889 /* We might have a duplicate key here. If so, entry is older
2890 than the key we've already put in the hash, so if they are
2891 the same, skip adding entry. */
2893 const STRLEN klen = HeKLEN(entry);
2894 const char *const key = HeKEY(entry);
2895 if (klen == chain->refcounted_he_keylen
2896 && (!!HeKUTF8(entry)
2897 == !!(chain->refcounted_he_data[0] & HVhek_UTF8))
2898 && memEQ(key, REF_HE_KEY(chain), klen))
2901 if (HeKEY_hek(entry) == chain->refcounted_he_hek)
2903 if (HeKLEN(entry) == HEK_LEN(chain->refcounted_he_hek)
2904 && HeKUTF8(entry) == HEK_UTF8(chain->refcounted_he_hek)
2905 && memEQ(HeKEY(entry), HEK_KEY(chain->refcounted_he_hek),
2916 = share_hek_flags(REF_HE_KEY(chain),
2917 chain->refcounted_he_keylen,
2918 chain->refcounted_he_hash,
2919 (chain->refcounted_he_data[0]
2920 & (HVhek_UTF8|HVhek_WASUTF8)));
2922 HeKEY_hek(entry) = share_hek_hek(chain->refcounted_he_hek);
2924 value = refcounted_he_value(chain);
2925 if (value == &PL_sv_placeholder)
2927 HeVAL(entry) = value;
2929 /* Link it into the chain. */
2930 HeNEXT(entry) = *oentry;
2936 chain = chain->refcounted_he_next;
2940 clear_placeholders(hv, placeholders);
2941 HvTOTALKEYS(hv) -= placeholders;
2944 /* We could check in the loop to see if we encounter any keys with key
2945 flags, but it's probably not worth it, as this per-hash flag is only
2946 really meant as an optimisation for things like Storable. */
2948 DEBUG_A(Perl_hv_assert(aTHX_ hv));
2954 =for apidoc m|SV *|refcounted_he_fetch_pvn|const struct refcounted_he *chain|const char *keypv|STRLEN keylen|U32 hash|U32 flags
2956 Search along a C<refcounted_he> chain for an entry with the key specified
2957 by I<keypv> and I<keylen>. If I<flags> has the C<REFCOUNTED_HE_KEY_UTF8>
2958 bit set, the key octets are interpreted as UTF-8, otherwise they
2959 are interpreted as Latin-1. I<hash> is a precomputed hash of the key
2960 string, or zero if it has not been precomputed. Returns a mortal scalar
2961 representing the value associated with the key, or C<&PL_sv_placeholder>
2962 if there is no value associated with the key.
2968 Perl_refcounted_he_fetch_pvn(pTHX_ const struct refcounted_he *chain,
2969 const char *keypv, STRLEN keylen, U32 hash, U32 flags)
2973 PERL_ARGS_ASSERT_REFCOUNTED_HE_FETCH_PVN;
2975 if (flags & ~REFCOUNTED_HE_KEY_UTF8)
2976 Perl_croak(aTHX_ "panic: refcounted_he_fetch_pvn bad flags %"UVxf,
2979 return &PL_sv_placeholder;
2980 if (flags & REFCOUNTED_HE_KEY_UTF8) {
2981 /* For searching purposes, canonicalise to Latin-1 where possible. */
2982 const char *keyend = keypv + keylen, *p;
2983 STRLEN nonascii_count = 0;
2984 for (p = keypv; p != keyend; p++) {
2987 if (!((c & 0xfe) == 0xc2 && ++p != keyend &&
2988 (((U8)*p) & 0xc0) == 0x80))
2989 goto canonicalised_key;
2993 if (nonascii_count) {
2995 const char *p = keypv, *keyend = keypv + keylen;
2996 keylen -= nonascii_count;
2997 Newx(q, keylen, char);
3000 for (; p != keyend; p++, q++) {
3003 ((c & 0x80) ? ((c & 0x03) << 6) | (((U8)*++p) & 0x3f) : c);
3006 flags &= ~REFCOUNTED_HE_KEY_UTF8;
3007 canonicalised_key: ;
3009 utf8_flag = (flags & REFCOUNTED_HE_KEY_UTF8) ? HVhek_UTF8 : 0;
3011 PERL_HASH(hash, keypv, keylen);
3013 for (; chain; chain = chain->refcounted_he_next) {
3016 hash == chain->refcounted_he_hash &&
3017 keylen == chain->refcounted_he_keylen &&
3018 memEQ(REF_HE_KEY(chain), keypv, keylen) &&
3019 utf8_flag == (chain->refcounted_he_data[0] & HVhek_UTF8)
3021 hash == HEK_HASH(chain->refcounted_he_hek) &&
3022 keylen == (STRLEN)HEK_LEN(chain->refcounted_he_hek) &&
3023 memEQ(HEK_KEY(chain->refcounted_he_hek), keypv, keylen) &&
3024 utf8_flag == (HEK_FLAGS(chain->refcounted_he_hek) & HVhek_UTF8)
3027 return sv_2mortal(refcounted_he_value(chain));
3029 return &PL_sv_placeholder;
3033 =for apidoc m|SV *|refcounted_he_fetch_pv|const struct refcounted_he *chain|const char *key|U32 hash|U32 flags
3035 Like L</refcounted_he_fetch_pvn>, but takes a nul-terminated string
3036 instead of a string/length pair.
3042 Perl_refcounted_he_fetch_pv(pTHX_ const struct refcounted_he *chain,
3043 const char *key, U32 hash, U32 flags)
3045 PERL_ARGS_ASSERT_REFCOUNTED_HE_FETCH_PV;
3046 return refcounted_he_fetch_pvn(chain, key, strlen(key), hash, flags);
3050 =for apidoc m|SV *|refcounted_he_fetch_sv|const struct refcounted_he *chain|SV *key|U32 hash|U32 flags
3052 Like L</refcounted_he_fetch_pvn>, but takes a Perl scalar instead of a
3059 Perl_refcounted_he_fetch_sv(pTHX_ const struct refcounted_he *chain,
3060 SV *key, U32 hash, U32 flags)
3064 PERL_ARGS_ASSERT_REFCOUNTED_HE_FETCH_SV;
3065 if (flags & REFCOUNTED_HE_KEY_UTF8)
3066 Perl_croak(aTHX_ "panic: refcounted_he_fetch_sv bad flags %"UVxf,
3068 keypv = SvPV_const(key, keylen);
3070 flags |= REFCOUNTED_HE_KEY_UTF8;
3071 if (!hash && SvIsCOW_shared_hash(key))
3072 hash = SvSHARED_HASH(key);
3073 return refcounted_he_fetch_pvn(chain, keypv, keylen, hash, flags);
3077 =for apidoc m|struct refcounted_he *|refcounted_he_new_pvn|struct refcounted_he *parent|const char *keypv|STRLEN keylen|U32 hash|SV *value|U32 flags
3079 Creates a new C<refcounted_he>. This consists of a single key/value
3080 pair and a reference to an existing C<refcounted_he> chain (which may
3081 be empty), and thus forms a longer chain. When using the longer chain,
3082 the new key/value pair takes precedence over any entry for the same key
3083 further along the chain.
3085 The new key is specified by I<keypv> and I<keylen>. If I<flags> has
3086 the C<REFCOUNTED_HE_KEY_UTF8> bit set, the key octets are interpreted
3087 as UTF-8, otherwise they are interpreted as Latin-1. I<hash> is
3088 a precomputed hash of the key string, or zero if it has not been
3091 I<value> is the scalar value to store for this key. I<value> is copied
3092 by this function, which thus does not take ownership of any reference
3093 to it, and later changes to the scalar will not be reflected in the
3094 value visible in the C<refcounted_he>. Complex types of scalar will not
3095 be stored with referential integrity, but will be coerced to strings.
3096 I<value> may be either null or C<&PL_sv_placeholder> to indicate that no
3097 value is to be associated with the key; this, as with any non-null value,
3098 takes precedence over the existence of a value for the key further along
3101 I<parent> points to the rest of the C<refcounted_he> chain to be
3102 attached to the new C<refcounted_he>. This function takes ownership
3103 of one reference to I<parent>, and returns one reference to the new
3109 struct refcounted_he *
3110 Perl_refcounted_he_new_pvn(pTHX_ struct refcounted_he *parent,
3111 const char *keypv, STRLEN keylen, U32 hash, SV *value, U32 flags)
3114 STRLEN value_len = 0;
3115 const char *value_p = NULL;
3119 STRLEN key_offset = 1;
3120 struct refcounted_he *he;
3121 PERL_ARGS_ASSERT_REFCOUNTED_HE_NEW_PVN;
3123 if (!value || value == &PL_sv_placeholder) {
3124 value_type = HVrhek_delete;
3125 } else if (SvPOK(value)) {
3126 value_type = HVrhek_PV;
3127 } else if (SvIOK(value)) {
3128 value_type = SvUOK((const SV *)value) ? HVrhek_UV : HVrhek_IV;
3129 } else if (!SvOK(value)) {
3130 value_type = HVrhek_undef;
3132 value_type = HVrhek_PV;
3134 is_pv = value_type == HVrhek_PV;
3136 /* Do it this way so that the SvUTF8() test is after the SvPV, in case
3137 the value is overloaded, and doesn't yet have the UTF-8flag set. */
3138 value_p = SvPV_const(value, value_len);
3140 value_type = HVrhek_PV_UTF8;
3141 key_offset = value_len + 2;
3143 hekflags = value_type;
3145 if (flags & REFCOUNTED_HE_KEY_UTF8) {
3146 /* Canonicalise to Latin-1 where possible. */
3147 const char *keyend = keypv + keylen, *p;
3148 STRLEN nonascii_count = 0;
3149 for (p = keypv; p != keyend; p++) {
3152 if (!((c & 0xfe) == 0xc2 && ++p != keyend &&
3153 (((U8)*p) & 0xc0) == 0x80))
3154 goto canonicalised_key;
3158 if (nonascii_count) {
3160 const char *p = keypv, *keyend = keypv + keylen;
3161 keylen -= nonascii_count;
3162 Newx(q, keylen, char);
3165 for (; p != keyend; p++, q++) {
3168 ((c & 0x80) ? ((c & 0x03) << 6) | (((U8)*++p) & 0x3f) : c);
3171 flags &= ~REFCOUNTED_HE_KEY_UTF8;
3172 canonicalised_key: ;
3174 if (flags & REFCOUNTED_HE_KEY_UTF8)
3175 hekflags |= HVhek_UTF8;
3177 PERL_HASH(hash, keypv, keylen);
3180 he = (struct refcounted_he*)
3181 PerlMemShared_malloc(sizeof(struct refcounted_he) - 1
3185 he = (struct refcounted_he*)
3186 PerlMemShared_malloc(sizeof(struct refcounted_he) - 1
3190 he->refcounted_he_next = parent;
3193 Copy(value_p, he->refcounted_he_data + 1, value_len + 1, char);
3194 he->refcounted_he_val.refcounted_he_u_len = value_len;
3195 } else if (value_type == HVrhek_IV) {
3196 he->refcounted_he_val.refcounted_he_u_iv = SvIVX(value);
3197 } else if (value_type == HVrhek_UV) {
3198 he->refcounted_he_val.refcounted_he_u_uv = SvUVX(value);
3202 he->refcounted_he_hash = hash;
3203 he->refcounted_he_keylen = keylen;
3204 Copy(keypv, he->refcounted_he_data + key_offset, keylen, char);
3206 he->refcounted_he_hek = share_hek_flags(keypv, keylen, hash, hekflags);
3209 he->refcounted_he_data[0] = hekflags;
3210 he->refcounted_he_refcnt = 1;
3216 =for apidoc m|struct refcounted_he *|refcounted_he_new_pv|struct refcounted_he *parent|const char *key|U32 hash|SV *value|U32 flags
3218 Like L</refcounted_he_new_pvn>, but takes a nul-terminated string instead
3219 of a string/length pair.
3224 struct refcounted_he *
3225 Perl_refcounted_he_new_pv(pTHX_ struct refcounted_he *parent,
3226 const char *key, U32 hash, SV *value, U32 flags)
3228 PERL_ARGS_ASSERT_REFCOUNTED_HE_NEW_PV;
3229 return refcounted_he_new_pvn(parent, key, strlen(key), hash, value, flags);
3233 =for apidoc m|struct refcounted_he *|refcounted_he_new_sv|struct refcounted_he *parent|SV *key|U32 hash|SV *value|U32 flags
3235 Like L</refcounted_he_new_pvn>, but takes a Perl scalar instead of a
3241 struct refcounted_he *
3242 Perl_refcounted_he_new_sv(pTHX_ struct refcounted_he *parent,
3243 SV *key, U32 hash, SV *value, U32 flags)
3247 PERL_ARGS_ASSERT_REFCOUNTED_HE_NEW_SV;
3248 if (flags & REFCOUNTED_HE_KEY_UTF8)
3249 Perl_croak(aTHX_ "panic: refcounted_he_new_sv bad flags %"UVxf,
3251 keypv = SvPV_const(key, keylen);
3253 flags |= REFCOUNTED_HE_KEY_UTF8;
3254 if (!hash && SvIsCOW_shared_hash(key))
3255 hash = SvSHARED_HASH(key);
3256 return refcounted_he_new_pvn(parent, keypv, keylen, hash, value, flags);
3260 =for apidoc m|void|refcounted_he_free|struct refcounted_he *he
3262 Decrements the reference count of a C<refcounted_he> by one. If the
3263 reference count reaches zero the structure's memory is freed, which
3264 (recursively) causes a reduction of its parent C<refcounted_he>'s
3265 reference count. It is safe to pass a null pointer to this function:
3266 no action occurs in this case.
3272 Perl_refcounted_he_free(pTHX_ struct refcounted_he *he) {
3274 PERL_UNUSED_CONTEXT;
3277 struct refcounted_he *copy;
3281 new_count = --he->refcounted_he_refcnt;
3282 HINTS_REFCNT_UNLOCK;
3288 #ifndef USE_ITHREADS
3289 unshare_hek_or_pvn (he->refcounted_he_hek, 0, 0, 0);
3292 he = he->refcounted_he_next;
3293 PerlMemShared_free(copy);
3298 =for apidoc m|struct refcounted_he *|refcounted_he_inc|struct refcounted_he *he
3300 Increment the reference count of a C<refcounted_he>. The pointer to the
3301 C<refcounted_he> is also returned. It is safe to pass a null pointer
3302 to this function: no action occurs and a null pointer is returned.
3307 struct refcounted_he *
3308 Perl_refcounted_he_inc(pTHX_ struct refcounted_he *he)
3312 he->refcounted_he_refcnt++;
3313 HINTS_REFCNT_UNLOCK;
3318 /* pp_entereval is aware that labels are stored with a key ':' at the top of
3321 Perl_fetch_cop_label(pTHX_ COP *const cop, STRLEN *len, U32 *flags) {
3322 struct refcounted_he *const chain = cop->cop_hints_hash;
3324 PERL_ARGS_ASSERT_FETCH_COP_LABEL;
3329 if (chain->refcounted_he_keylen != 1)
3331 if (*REF_HE_KEY(chain) != ':')
3334 if ((STRLEN)HEK_LEN(chain->refcounted_he_hek) != 1)
3336 if (*HEK_KEY(chain->refcounted_he_hek) != ':')
3339 /* Stop anyone trying to really mess us up by adding their own value for
3341 if ((chain->refcounted_he_data[0] & HVrhek_typemask) != HVrhek_PV
3342 && (chain->refcounted_he_data[0] & HVrhek_typemask) != HVrhek_PV_UTF8)
3346 *len = chain->refcounted_he_val.refcounted_he_u_len;
3348 *flags = ((chain->refcounted_he_data[0] & HVrhek_typemask)
3349 == HVrhek_PV_UTF8) ? SVf_UTF8 : 0;
3351 return chain->refcounted_he_data + 1;
3355 Perl_store_cop_label(pTHX_ COP *const cop, const char *label, STRLEN len,
3359 PERL_ARGS_ASSERT_STORE_COP_LABEL;
3361 if (flags & ~(SVf_UTF8))
3362 Perl_croak(aTHX_ "panic: store_cop_label illegal flag bits 0x%" UVxf,
3364 labelsv = sv_2mortal(newSVpvn(label, len));
3365 if (flags & SVf_UTF8)
3368 = refcounted_he_new_pvs(cop->cop_hints_hash, ":", labelsv, 0);
3372 =for apidoc hv_assert
3374 Check that a hash is in an internally consistent state.
3382 Perl_hv_assert(pTHX_ HV *hv)
3387 int placeholders = 0;
3390 const I32 riter = HvRITER_get(hv);
3391 HE *eiter = HvEITER_get(hv);
3393 PERL_ARGS_ASSERT_HV_ASSERT;
3395 (void)hv_iterinit(hv);
3397 while ((entry = hv_iternext_flags(hv, HV_ITERNEXT_WANTPLACEHOLDERS))) {
3398 /* sanity check the values */
3399 if (HeVAL(entry) == &PL_sv_placeholder)
3403 /* sanity check the keys */
3404 if (HeSVKEY(entry)) {
3405 NOOP; /* Don't know what to check on SV keys. */
3406 } else if (HeKUTF8(entry)) {
3408 if (HeKWASUTF8(entry)) {
3409 PerlIO_printf(Perl_debug_log,
3410 "hash key has both WASUTF8 and UTF8: '%.*s'\n",
3411 (int) HeKLEN(entry), HeKEY(entry));
3414 } else if (HeKWASUTF8(entry))
3417 if (!SvTIED_mg((const SV *)hv, PERL_MAGIC_tied)) {
3418 static const char bad_count[] = "Count %d %s(s), but hash reports %d\n";
3419 const int nhashkeys = HvUSEDKEYS(hv);
3420 const int nhashplaceholders = HvPLACEHOLDERS_get(hv);
3422 if (nhashkeys != real) {
3423 PerlIO_printf(Perl_debug_log, bad_count, real, "keys", nhashkeys );
3426 if (nhashplaceholders != placeholders) {
3427 PerlIO_printf(Perl_debug_log, bad_count, placeholders, "placeholder", nhashplaceholders );
3431 if (withflags && ! HvHASKFLAGS(hv)) {
3432 PerlIO_printf(Perl_debug_log,
3433 "Hash has HASKFLAGS off but I count %d key(s) with flags\n",
3438 sv_dump(MUTABLE_SV(hv));
3440 HvRITER_set(hv, riter); /* Restore hash iterator state */
3441 HvEITER_set(hv, eiter);
3448 * c-indentation-style: bsd
3450 * indent-tabs-mode: t
3453 * ex: set ts=8 sts=4 sw=4 noet: