3 * Copyright (C) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
4 * 2000, 2001, 2002, 2003, 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 of all that I have seen." --Bilbo
16 =head1 Hash Manipulation Functions
21 #define PERL_HASH_INTERNAL_ACCESS
24 #define HV_MAX_LENGTH_BEFORE_SPLIT 14
34 PL_he_root = HeNEXT(he);
43 HeNEXT(p) = (HE*)PL_he_root;
54 New(54, ptr, 1008/sizeof(XPV), XPV);
55 ptr->xpv_pv = (char*)PL_he_arenaroot;
56 PL_he_arenaroot = ptr;
59 heend = &he[1008 / sizeof(HE) - 1];
62 HeNEXT(he) = (HE*)(he + 1);
70 #define new_HE() (HE*)safemalloc(sizeof(HE))
71 #define del_HE(p) safefree((char*)p)
75 #define new_HE() new_he()
76 #define del_HE(p) del_he(p)
81 S_save_hek_flags(pTHX_ const char *str, I32 len, U32 hash, int flags)
83 int flags_masked = flags & HVhek_MASK;
87 New(54, k, HEK_BASESIZE + len + 2, char);
89 Copy(str, HEK_KEY(hek), len, char);
90 HEK_KEY(hek)[len] = 0;
93 HEK_FLAGS(hek) = (unsigned char)flags_masked;
95 if (flags & HVhek_FREEKEY)
100 /* free the pool of temporary HE/HEK pairs retunrned by hv_fetch_ent
104 Perl_free_tied_hv_pool(pTHX)
107 HE *he = PL_hv_fetch_ent_mh;
109 Safefree(HeKEY_hek(he));
114 PL_hv_fetch_ent_mh = Nullhe;
117 #if defined(USE_ITHREADS)
119 Perl_he_dup(pTHX_ HE *e, bool shared, CLONE_PARAMS* param)
125 /* look for it in the table first */
126 ret = (HE*)ptr_table_fetch(PL_ptr_table, e);
130 /* create anew and remember what it is */
132 ptr_table_store(PL_ptr_table, e, ret);
134 HeNEXT(ret) = he_dup(HeNEXT(e),shared, param);
135 if (HeKLEN(e) == HEf_SVKEY) {
137 New(54, k, HEK_BASESIZE + sizeof(SV*), char);
138 HeKEY_hek(ret) = (HEK*)k;
139 HeKEY_sv(ret) = SvREFCNT_inc(sv_dup(HeKEY_sv(e), param));
142 HeKEY_hek(ret) = share_hek_flags(HeKEY(e), HeKLEN(e), HeHASH(e),
145 HeKEY_hek(ret) = save_hek_flags(HeKEY(e), HeKLEN(e), HeHASH(e),
147 HeVAL(ret) = SvREFCNT_inc(sv_dup(HeVAL(e), param));
150 #endif /* USE_ITHREADS */
153 S_hv_notallowed(pTHX_ int flags, const char *key, I32 klen,
156 SV *sv = sv_newmortal(), *esv = sv_newmortal();
157 if (!(flags & HVhek_FREEKEY)) {
158 sv_setpvn(sv, key, klen);
161 /* Need to free saved eventually assign to mortal SV */
162 /* XXX is this line an error ???: SV *sv = sv_newmortal(); */
163 sv_usepvn(sv, (char *) key, klen);
165 if (flags & HVhek_UTF8) {
168 Perl_sv_setpvf(aTHX_ esv, "Attempt to %s a restricted hash", msg);
169 Perl_croak(aTHX_ SvPVX(esv), sv);
172 /* (klen == HEf_SVKEY) is special for MAGICAL hv entries, meaning key slot
175 #define HV_FETCH_ISSTORE 0x01
176 #define HV_FETCH_ISEXISTS 0x02
177 #define HV_FETCH_LVALUE 0x04
178 #define HV_FETCH_JUST_SV 0x08
183 Stores an SV in a hash. The hash key is specified as C<key> and C<klen> is
184 the length of the key. The C<hash> parameter is the precomputed hash
185 value; if it is zero then Perl will compute it. The return value will be
186 NULL if the operation failed or if the value did not need to be actually
187 stored within the hash (as in the case of tied hashes). Otherwise it can
188 be dereferenced to get the original C<SV*>. Note that the caller is
189 responsible for suitably incrementing the reference count of C<val> before
190 the call, and decrementing it if the function returned NULL. Effectively
191 a successful hv_store takes ownership of one reference to C<val>. This is
192 usually what you want; a newly created SV has a reference count of one, so
193 if all your code does is create SVs then store them in a hash, hv_store
194 will own the only reference to the new SV, and your code doesn't need to do
195 anything further to tidy up. hv_store is not implemented as a call to
196 hv_store_ent, and does not create a temporary SV for the key, so if your
197 key data is not already in SV form then use hv_store in preference to
200 See L<perlguts/"Understanding the Magic of Tied Hashes and Arrays"> for more
201 information on how to use this function on tied hashes.
207 Perl_hv_store(pTHX_ HV *hv, const char *key, I32 klen_i32, SV *val, U32 hash)
220 hek = hv_fetch_common (hv, NULL, key, klen, flags,
221 (HV_FETCH_ISSTORE|HV_FETCH_JUST_SV), val, 0);
222 return hek ? &HeVAL(hek) : NULL;
226 Perl_hv_store_flags(pTHX_ HV *hv, const char *key, I32 klen, SV *val,
227 register U32 hash, int flags)
229 HE *hek = hv_fetch_common (hv, NULL, key, klen, flags,
230 (HV_FETCH_ISSTORE|HV_FETCH_JUST_SV), val, hash);
231 return hek ? &HeVAL(hek) : NULL;
235 =for apidoc hv_store_ent
237 Stores C<val> in a hash. The hash key is specified as C<key>. The C<hash>
238 parameter is the precomputed hash value; if it is zero then Perl will
239 compute it. The return value is the new hash entry so created. It will be
240 NULL if the operation failed or if the value did not need to be actually
241 stored within the hash (as in the case of tied hashes). Otherwise the
242 contents of the return value can be accessed using the C<He?> macros
243 described here. Note that the caller is responsible for suitably
244 incrementing the reference count of C<val> before the call, and
245 decrementing it if the function returned NULL. Effectively a successful
246 hv_store_ent takes ownership of one reference to C<val>. This is
247 usually what you want; a newly created SV has a reference count of one, so
248 if all your code does is create SVs then store them in a hash, hv_store
249 will own the only reference to the new SV, and your code doesn't need to do
250 anything further to tidy up. Note that hv_store_ent only reads the C<key>;
251 unlike C<val> it does not take ownership of it, so maintaining the correct
252 reference count on C<key> is entirely the caller's responsibility. hv_store
253 is not implemented as a call to hv_store_ent, and does not create a temporary
254 SV for the key, so if your key data is not already in SV form then use
255 hv_store in preference to hv_store_ent.
257 See L<perlguts/"Understanding the Magic of Tied Hashes and Arrays"> for more
258 information on how to use this function on tied hashes.
264 Perl_hv_store_ent(pTHX_ HV *hv, SV *keysv, SV *val, U32 hash)
266 return hv_fetch_common(hv, keysv, NULL, 0, 0, HV_FETCH_ISSTORE, val, hash);
270 =for apidoc hv_exists
272 Returns a boolean indicating whether the specified hash key exists. The
273 C<klen> is the length of the key.
279 Perl_hv_exists(pTHX_ HV *hv, const char *key, I32 klen_i32)
291 return hv_fetch_common(hv, NULL, key, klen, flags, HV_FETCH_ISEXISTS, 0, 0)
298 Returns the SV which corresponds to the specified key in the hash. The
299 C<klen> is the length of the key. If C<lval> is set then the fetch will be
300 part of a store. Check that the return value is non-null before
301 dereferencing it to an C<SV*>.
303 See L<perlguts/"Understanding the Magic of Tied Hashes and Arrays"> for more
304 information on how to use this function on tied hashes.
310 Perl_hv_fetch(pTHX_ HV *hv, const char *key, I32 klen_i32, I32 lval)
323 hek = hv_fetch_common (hv, NULL, key, klen, flags,
324 HV_FETCH_JUST_SV | (lval ? HV_FETCH_LVALUE : 0),
326 return hek ? &HeVAL(hek) : NULL;
330 =for apidoc hv_exists_ent
332 Returns a boolean indicating whether the specified hash key exists. C<hash>
333 can be a valid precomputed hash value, or 0 to ask for it to be
340 Perl_hv_exists_ent(pTHX_ HV *hv, SV *keysv, U32 hash)
342 return hv_fetch_common(hv, keysv, NULL, 0, 0, HV_FETCH_ISEXISTS, 0, hash)
346 /* returns an HE * structure with the all fields set */
347 /* note that hent_val will be a mortal sv for MAGICAL hashes */
349 =for apidoc hv_fetch_ent
351 Returns the hash entry which corresponds to the specified key in the hash.
352 C<hash> must be a valid precomputed hash number for the given C<key>, or 0
353 if you want the function to compute it. IF C<lval> is set then the fetch
354 will be part of a store. Make sure the return value is non-null before
355 accessing it. The return value when C<tb> is a tied hash is a pointer to a
356 static location, so be sure to make a copy of the structure if you need to
359 See L<perlguts/"Understanding the Magic of Tied Hashes and Arrays"> for more
360 information on how to use this function on tied hashes.
366 Perl_hv_fetch_ent(pTHX_ HV *hv, SV *keysv, I32 lval, register U32 hash)
368 return hv_fetch_common(hv, keysv, NULL, 0, 0,
369 (lval ? HV_FETCH_LVALUE : 0), Nullsv, hash);
373 S_hv_fetch_common(pTHX_ HV *hv, SV *keysv, const char *key, STRLEN klen,
374 int flags, int action, SV *val, register U32 hash)
388 if (flags & HVhek_FREEKEY)
390 key = SvPV(keysv, klen);
392 is_utf8 = (SvUTF8(keysv) != 0);
394 is_utf8 = ((flags & HVhek_UTF8) ? TRUE : FALSE);
397 xhv = (XPVHV*)SvANY(hv);
399 if (SvRMAGICAL(hv) && !(action & (HV_FETCH_ISSTORE|HV_FETCH_ISEXISTS)))
401 if (mg_find((SV*)hv, PERL_MAGIC_tied) || SvGMAGICAL((SV*)hv)) {
404 /* XXX should be able to skimp on the HE/HEK here when
405 HV_FETCH_JUST_SV is true. */
408 keysv = newSVpvn(key, klen);
413 keysv = newSVsv(keysv);
415 mg_copy((SV*)hv, sv, (char *)keysv, HEf_SVKEY);
417 /* grab a fake HE/HEK pair from the pool or make a new one */
418 entry = PL_hv_fetch_ent_mh;
420 PL_hv_fetch_ent_mh = HeNEXT(entry);
424 New(54, k, HEK_BASESIZE + sizeof(SV*), char);
425 HeKEY_hek(entry) = (HEK*)k;
427 HeNEXT(entry) = Nullhe;
428 HeSVKEY_set(entry, keysv);
430 sv_upgrade(sv, SVt_PVLV);
432 /* so we can free entry when freeing sv */
433 LvTARG(sv) = (SV*)entry;
435 /* XXX remove at some point? */
436 if (flags & HVhek_FREEKEY)
441 #ifdef ENV_IS_CASELESS
442 else if (mg_find((SV*)hv, PERL_MAGIC_env)) {
444 for (i = 0; i < klen; ++i)
445 if (isLOWER(key[i])) {
446 /* Would be nice if we had a routine to do the
447 copy and upercase in a single pass through. */
448 char *nkey = strupr(savepvn(key,klen));
449 /* Note that this fetch is for nkey (the uppercased
450 key) whereas the store is for key (the original) */
451 entry = hv_fetch_common(hv, Nullsv, nkey, klen,
452 HVhek_FREEKEY, /* free nkey */
453 0 /* non-LVAL fetch */,
454 Nullsv /* no value */,
455 0 /* compute hash */);
456 if (!entry && (action & HV_FETCH_LVALUE)) {
457 /* This call will free key if necessary.
458 Do it this way to encourage compiler to tail
460 entry = hv_fetch_common(hv, keysv, key, klen,
461 flags, HV_FETCH_ISSTORE,
464 if (flags & HVhek_FREEKEY)
472 else if (SvRMAGICAL(hv) && (action & HV_FETCH_ISEXISTS)) {
473 if (mg_find((SV*)hv, PERL_MAGIC_tied) || SvGMAGICAL((SV*)hv)) {
475 /* I don't understand why hv_exists_ent has svret and sv,
476 whereas hv_exists only had one. */
477 svret = sv_newmortal();
480 if (keysv || is_utf8) {
482 keysv = newSVpvn(key, klen);
485 keysv = newSVsv(keysv);
487 mg_copy((SV*)hv, sv, (char *)sv_2mortal(keysv), HEf_SVKEY);
489 mg_copy((SV*)hv, sv, key, klen);
491 if (flags & HVhek_FREEKEY)
493 magic_existspack(svret, mg_find(sv, PERL_MAGIC_tiedelem));
494 /* This cast somewhat evil, but I'm merely using NULL/
495 not NULL to return the boolean exists.
496 And I know hv is not NULL. */
497 return SvTRUE(svret) ? (HE *)hv : NULL;
499 #ifdef ENV_IS_CASELESS
500 else if (mg_find((SV*)hv, PERL_MAGIC_env)) {
501 /* XXX This code isn't UTF8 clean. */
502 const char *keysave = key;
503 /* Will need to free this, so set FREEKEY flag. */
504 key = savepvn(key,klen);
505 key = (const char*)strupr((char*)key);
509 if (flags & HVhek_FREEKEY) {
512 flags |= HVhek_FREEKEY;
516 else if (action & HV_FETCH_ISSTORE) {
519 hv_magic_check (hv, &needs_copy, &needs_store);
521 bool save_taint = PL_tainted;
522 if (keysv || is_utf8) {
524 keysv = newSVpvn(key, klen);
528 PL_tainted = SvTAINTED(keysv);
529 keysv = sv_2mortal(newSVsv(keysv));
530 mg_copy((SV*)hv, val, (char*)keysv, HEf_SVKEY);
532 mg_copy((SV*)hv, val, key, klen);
535 TAINT_IF(save_taint);
536 if (!xhv->xhv_array /* !HvARRAY(hv) */ && !needs_store) {
537 if (flags & HVhek_FREEKEY)
541 #ifdef ENV_IS_CASELESS
542 else if (mg_find((SV*)hv, PERL_MAGIC_env)) {
543 /* XXX This code isn't UTF8 clean. */
544 const char *keysave = key;
545 /* Will need to free this, so set FREEKEY flag. */
546 key = savepvn(key,klen);
547 key = (const char*)strupr((char*)key);
551 if (flags & HVhek_FREEKEY) {
554 flags |= HVhek_FREEKEY;
561 if (!xhv->xhv_array /* !HvARRAY(hv) */) {
562 if ((action & (HV_FETCH_LVALUE | HV_FETCH_ISSTORE))
563 #ifdef DYNAMIC_ENV_FETCH /* if it's an %ENV lookup, we may get it on the fly */
564 || (SvRMAGICAL((SV*)hv) && mg_find((SV*)hv, PERL_MAGIC_env))
567 Newz(503, xhv->xhv_array /* HvARRAY(hv) */,
568 PERL_HV_ARRAY_ALLOC_BYTES(xhv->xhv_max+1 /* HvMAX(hv)+1 */),
570 #ifdef DYNAMIC_ENV_FETCH
571 else if (action & HV_FETCH_ISEXISTS) {
572 /* for an %ENV exists, if we do an insert it's by a recursive
573 store call, so avoid creating HvARRAY(hv) right now. */
577 /* XXX remove at some point? */
578 if (flags & HVhek_FREEKEY)
586 const char *keysave = key;
587 key = (char*)bytes_from_utf8((U8*)key, &klen, &is_utf8);
591 flags &= ~HVhek_UTF8;
592 if (key != keysave) {
593 if (flags & HVhek_FREEKEY)
595 flags |= HVhek_WASUTF8 | HVhek_FREEKEY;
600 PERL_HASH_INTERNAL(hash, key, klen);
601 /* We don't have a pointer to the hv, so we have to replicate the
602 flag into every HEK, so that hv_iterkeysv can see it. */
603 /* And yes, you do need this even though you are not "storing" because
604 you can flip the flags below if doing an lval lookup. (And that
605 was put in to give the semantics Andreas was expecting.) */
606 flags |= HVhek_REHASH;
608 if (keysv && (SvIsCOW_shared_hash(keysv))) {
611 PERL_HASH(hash, key, klen);
615 masked_flags = (flags & HVhek_MASK);
618 #ifdef DYNAMIC_ENV_FETCH
619 if (!xhv->xhv_array /* !HvARRAY(hv) */) entry = Null(HE*);
623 /* entry = (HvARRAY(hv))[hash & (I32) HvMAX(hv)]; */
624 entry = ((HE**)xhv->xhv_array)[hash & (I32) xhv->xhv_max];
626 for (; entry; ++n_links, entry = HeNEXT(entry)) {
627 if (HeHASH(entry) != hash) /* strings can't be equal */
629 if (HeKLEN(entry) != (I32)klen)
631 if (HeKEY(entry) != key && memNE(HeKEY(entry),key,klen)) /* is this it? */
633 if ((HeKFLAGS(entry) ^ masked_flags) & HVhek_UTF8)
636 if (action & (HV_FETCH_LVALUE|HV_FETCH_ISSTORE)) {
637 if (HeKFLAGS(entry) != masked_flags) {
638 /* We match if HVhek_UTF8 bit in our flags and hash key's
639 match. But if entry was set previously with HVhek_WASUTF8
640 and key now doesn't (or vice versa) then we should change
641 the key's flag, as this is assignment. */
642 if (HvSHAREKEYS(hv)) {
643 /* Need to swap the key we have for a key with the flags we
644 need. As keys are shared we can't just write to the
645 flag, so we share the new one, unshare the old one. */
646 HEK *new_hek = share_hek_flags(key, klen, hash,
648 unshare_hek (HeKEY_hek(entry));
649 HeKEY_hek(entry) = new_hek;
652 HeKFLAGS(entry) = masked_flags;
653 if (masked_flags & HVhek_ENABLEHVKFLAGS)
656 if (HeVAL(entry) == &PL_sv_placeholder) {
657 /* yes, can store into placeholder slot */
658 if (action & HV_FETCH_LVALUE) {
660 /* This preserves behaviour with the old hv_fetch
661 implementation which at this point would bail out
662 with a break; (at "if we find a placeholder, we
663 pretend we haven't found anything")
665 That break mean that if a placeholder were found, it
666 caused a call into hv_store, which in turn would
667 check magic, and if there is no magic end up pretty
668 much back at this point (in hv_store's code). */
671 /* LVAL fetch which actaully needs a store. */
673 xhv->xhv_placeholders--;
676 if (val != &PL_sv_placeholder)
677 xhv->xhv_placeholders--;
680 } else if (action & HV_FETCH_ISSTORE) {
681 SvREFCNT_dec(HeVAL(entry));
684 } else if (HeVAL(entry) == &PL_sv_placeholder) {
685 /* if we find a placeholder, we pretend we haven't found
689 if (flags & HVhek_FREEKEY)
693 #ifdef DYNAMIC_ENV_FETCH /* %ENV lookup? If so, try to fetch the value now */
694 if (!(action & HV_FETCH_ISSTORE)
695 && SvRMAGICAL((SV*)hv) && mg_find((SV*)hv, PERL_MAGIC_env)) {
697 char *env = PerlEnv_ENVgetenv_len(key,&len);
699 sv = newSVpvn(env,len);
701 return hv_fetch_common(hv,keysv,key,klen,flags,HV_FETCH_ISSTORE,sv,
707 if (!entry && SvREADONLY(hv) && !(action & HV_FETCH_ISEXISTS)) {
708 S_hv_notallowed(aTHX_ flags, key, klen,
709 "access disallowed key '%"SVf"' in"
712 if (!(action & (HV_FETCH_LVALUE|HV_FETCH_ISSTORE))) {
713 /* Not doing some form of store, so return failure. */
714 if (flags & HVhek_FREEKEY)
718 if (action & HV_FETCH_LVALUE) {
721 /* At this point the old hv_fetch code would call to hv_store,
722 which in turn might do some tied magic. So we need to make that
723 magic check happen. */
724 /* gonna assign to this, so it better be there */
725 return hv_fetch_common(hv, keysv, key, klen, flags,
726 HV_FETCH_ISSTORE, val, hash);
727 /* XXX Surely that could leak if the fetch-was-store fails?
728 Just like the hv_fetch. */
732 /* Welcome to hv_store... */
734 if (!xhv->xhv_array) {
735 /* Not sure if we can get here. I think the only case of oentry being
736 NULL is for %ENV with dynamic env fetch. But that should disappear
737 with magic in the previous code. */
738 Newz(503, xhv->xhv_array /* HvARRAY(hv) */,
739 PERL_HV_ARRAY_ALLOC_BYTES(xhv->xhv_max+1 /* HvMAX(hv)+1 */),
743 oentry = &((HE**)xhv->xhv_array)[hash & (I32) xhv->xhv_max];
746 /* share_hek_flags will do the free for us. This might be considered
749 HeKEY_hek(entry) = share_hek_flags(key, klen, hash, flags);
750 else /* gotta do the real thing */
751 HeKEY_hek(entry) = save_hek_flags(key, klen, hash, flags);
753 HeNEXT(entry) = *oentry;
756 if (val == &PL_sv_placeholder)
757 xhv->xhv_placeholders++;
758 if (masked_flags & HVhek_ENABLEHVKFLAGS)
761 xhv->xhv_keys++; /* HvKEYS(hv)++ */
762 if (!n_links) { /* initial entry? */
763 xhv->xhv_fill++; /* HvFILL(hv)++ */
764 } else if ((xhv->xhv_keys > (IV)xhv->xhv_max)
765 || ((n_links > HV_MAX_LENGTH_BEFORE_SPLIT) && !HvREHASH(hv))) {
766 /* Use only the old HvKEYS(hv) > HvMAX(hv) condition to limit bucket
767 splits on a rehashed hash, as we're not going to split it again,
768 and if someone is lucky (evil) enough to get all the keys in one
769 list they could exhaust our memory as we repeatedly double the
770 number of buckets on every entry. Linear search feels a less worse
779 S_hv_magic_check(pTHX_ HV *hv, bool *needs_copy, bool *needs_store)
781 MAGIC *mg = SvMAGIC(hv);
785 if (isUPPER(mg->mg_type)) {
787 switch (mg->mg_type) {
788 case PERL_MAGIC_tied:
790 *needs_store = FALSE;
793 mg = mg->mg_moremagic;
798 =for apidoc hv_scalar
800 Evaluates the hash in scalar context and returns the result. Handles magic when the hash is tied.
806 Perl_hv_scalar(pTHX_ HV *hv)
811 if ((SvRMAGICAL(hv) && (mg = mg_find((SV*)hv, PERL_MAGIC_tied)))) {
812 sv = magic_scalarpack(hv, mg);
818 Perl_sv_setpvf(aTHX_ sv, "%ld/%ld",
819 (long)HvFILL(hv), (long)HvMAX(hv) + 1);
827 =for apidoc hv_delete
829 Deletes a key/value pair in the hash. The value SV is removed from the
830 hash and returned to the caller. The C<klen> is the length of the key.
831 The C<flags> value will normally be zero; if set to G_DISCARD then NULL
838 Perl_hv_delete(pTHX_ HV *hv, const char *key, I32 klen_i32, I32 flags)
845 k_flags |= HVhek_UTF8;
849 return hv_delete_common(hv, NULL, key, klen, k_flags, flags, 0);
853 =for apidoc hv_delete_ent
855 Deletes a key/value pair in the hash. The value SV is removed from the
856 hash and returned to the caller. The C<flags> value will normally be zero;
857 if set to G_DISCARD then NULL will be returned. C<hash> can be a valid
858 precomputed hash value, or 0 to ask for it to be computed.
864 Perl_hv_delete_ent(pTHX_ HV *hv, SV *keysv, I32 flags, U32 hash)
866 return hv_delete_common(hv, keysv, NULL, 0, 0, flags, hash);
870 S_hv_delete_common(pTHX_ HV *hv, SV *keysv, const char *key, STRLEN klen,
871 int k_flags, I32 d_flags, U32 hash)
876 register HE **oentry;
885 if (k_flags & HVhek_FREEKEY)
887 key = SvPV(keysv, klen);
889 is_utf8 = (SvUTF8(keysv) != 0);
891 is_utf8 = ((k_flags & HVhek_UTF8) ? TRUE : FALSE);
894 if (SvRMAGICAL(hv)) {
897 hv_magic_check (hv, &needs_copy, &needs_store);
900 entry = hv_fetch_common(hv, keysv, key, klen,
901 k_flags & ~HVhek_FREEKEY, HV_FETCH_LVALUE,
903 sv = entry ? HeVAL(entry) : NULL;
909 if (mg_find(sv, PERL_MAGIC_tiedelem)) {
910 /* No longer an element */
911 sv_unmagic(sv, PERL_MAGIC_tiedelem);
914 return Nullsv; /* element cannot be deleted */
916 #ifdef ENV_IS_CASELESS
917 else if (mg_find((SV*)hv, PERL_MAGIC_env)) {
918 /* XXX This code isn't UTF8 clean. */
919 keysv = sv_2mortal(newSVpvn(key,klen));
920 if (k_flags & HVhek_FREEKEY) {
923 key = strupr(SvPVX(keysv));
932 xhv = (XPVHV*)SvANY(hv);
933 if (!xhv->xhv_array /* !HvARRAY(hv) */)
937 const char *keysave = key;
938 key = (char*)bytes_from_utf8((U8*)key, &klen, &is_utf8);
941 k_flags |= HVhek_UTF8;
943 k_flags &= ~HVhek_UTF8;
944 if (key != keysave) {
945 if (k_flags & HVhek_FREEKEY) {
946 /* This shouldn't happen if our caller does what we expect,
947 but strictly the API allows it. */
950 k_flags |= HVhek_WASUTF8 | HVhek_FREEKEY;
952 HvHASKFLAGS_on((SV*)hv);
956 PERL_HASH_INTERNAL(hash, key, klen);
958 if (keysv && (SvIsCOW_shared_hash(keysv))) {
961 PERL_HASH(hash, key, klen);
965 masked_flags = (k_flags & HVhek_MASK);
967 /* oentry = &(HvARRAY(hv))[hash & (I32) HvMAX(hv)]; */
968 oentry = &((HE**)xhv->xhv_array)[hash & (I32) xhv->xhv_max];
971 for (; entry; i=0, oentry = &HeNEXT(entry), entry = *oentry) {
972 if (HeHASH(entry) != hash) /* strings can't be equal */
974 if (HeKLEN(entry) != (I32)klen)
976 if (HeKEY(entry) != key && memNE(HeKEY(entry),key,klen)) /* is this it? */
978 if ((HeKFLAGS(entry) ^ masked_flags) & HVhek_UTF8)
980 if (k_flags & HVhek_FREEKEY)
983 /* if placeholder is here, it's already been deleted.... */
984 if (HeVAL(entry) == &PL_sv_placeholder)
988 else if (SvREADONLY(hv) && HeVAL(entry) && SvREADONLY(HeVAL(entry))) {
989 S_hv_notallowed(aTHX_ k_flags, key, klen,
990 "delete readonly key '%"SVf"' from"
994 if (d_flags & G_DISCARD)
997 sv = sv_2mortal(HeVAL(entry));
998 HeVAL(entry) = &PL_sv_placeholder;
1002 * If a restricted hash, rather than really deleting the entry, put
1003 * a placeholder there. This marks the key as being "approved", so
1004 * we can still access via not-really-existing key without raising
1007 if (SvREADONLY(hv)) {
1008 SvREFCNT_dec(HeVAL(entry));
1009 HeVAL(entry) = &PL_sv_placeholder;
1010 /* We'll be saving this slot, so the number of allocated keys
1011 * doesn't go down, but the number placeholders goes up */
1012 xhv->xhv_placeholders++; /* HvPLACEHOLDERS(hv)++ */
1014 *oentry = HeNEXT(entry);
1016 xhv->xhv_fill--; /* HvFILL(hv)-- */
1017 if (entry == xhv->xhv_eiter /* HvEITER(hv) */)
1020 hv_free_ent(hv, entry);
1021 xhv->xhv_keys--; /* HvKEYS(hv)-- */
1022 if (xhv->xhv_keys == 0)
1023 HvHASKFLAGS_off(hv);
1027 if (SvREADONLY(hv)) {
1028 S_hv_notallowed(aTHX_ k_flags, key, klen,
1029 "delete disallowed key '%"SVf"' from"
1033 if (k_flags & HVhek_FREEKEY)
1039 S_hsplit(pTHX_ HV *hv)
1041 /* Can't make this clear any placeholders first for non-restricted hashes,
1042 as Storable rebuilds restricted hashes by putting in all the
1043 placeholders (first) before turning on the readonly flag. Hence midway
1044 through restoring the hash there are placeholders which need to remain
1045 even though the hash isn't (currently) flagged as restricted. */
1046 register XPVHV* xhv = (XPVHV*)SvANY(hv);
1047 I32 oldsize = (I32) xhv->xhv_max+1; /* HvMAX(hv)+1 (sick) */
1048 register I32 newsize = oldsize * 2;
1050 register char *a = xhv->xhv_array; /* HvARRAY(hv) */
1054 register HE **oentry;
1055 int longest_chain = 0;
1059 #if defined(STRANGE_MALLOC) || defined(MYMALLOC)
1060 Renew(a, PERL_HV_ARRAY_ALLOC_BYTES(newsize), char);
1066 New(2, a, PERL_HV_ARRAY_ALLOC_BYTES(newsize), char);
1071 Copy(xhv->xhv_array /* HvARRAY(hv) */, a, oldsize * sizeof(HE*), char);
1072 if (oldsize >= 64) {
1073 offer_nice_chunk(xhv->xhv_array /* HvARRAY(hv) */,
1074 PERL_HV_ARRAY_ALLOC_BYTES(oldsize));
1077 Safefree(xhv->xhv_array /* HvARRAY(hv) */);
1081 Zero(&a[oldsize * sizeof(HE*)], (newsize-oldsize) * sizeof(HE*), char); /* zero 2nd half*/
1082 xhv->xhv_max = --newsize; /* HvMAX(hv) = --newsize */
1083 xhv->xhv_array = a; /* HvARRAY(hv) = a */
1086 for (i=0; i<oldsize; i++,aep++) {
1087 int left_length = 0;
1088 int right_length = 0;
1090 if (!*aep) /* non-existent */
1093 for (oentry = aep, entry = *aep; entry; entry = *oentry) {
1094 if ((HeHASH(entry) & newsize) != (U32)i) {
1095 *oentry = HeNEXT(entry);
1096 HeNEXT(entry) = *bep;
1098 xhv->xhv_fill++; /* HvFILL(hv)++ */
1104 oentry = &HeNEXT(entry);
1108 if (!*aep) /* everything moved */
1109 xhv->xhv_fill--; /* HvFILL(hv)-- */
1110 /* I think we don't actually need to keep track of the longest length,
1111 merely flag if anything is too long. But for the moment while
1112 developing this code I'll track it. */
1113 if (left_length > longest_chain)
1114 longest_chain = left_length;
1115 if (right_length > longest_chain)
1116 longest_chain = right_length;
1120 /* Pick your policy for "hashing isn't working" here: */
1121 if (longest_chain <= HV_MAX_LENGTH_BEFORE_SPLIT /* split worked? */
1126 if (hv == PL_strtab) {
1127 /* Urg. Someone is doing something nasty to the string table.
1132 /* Awooga. Awooga. Pathological data. */
1133 /*PerlIO_printf(PerlIO_stderr(), "%p %d of %d with %d/%d buckets\n", hv,
1134 longest_chain, HvTOTALKEYS(hv), HvFILL(hv), 1+HvMAX(hv));*/
1137 Newz(2, a, PERL_HV_ARRAY_ALLOC_BYTES(newsize), char);
1138 was_shared = HvSHAREKEYS(hv);
1141 HvSHAREKEYS_off(hv);
1144 aep = (HE **) xhv->xhv_array;
1146 for (i=0; i<newsize; i++,aep++) {
1149 /* We're going to trash this HE's next pointer when we chain it
1150 into the new hash below, so store where we go next. */
1151 HE *next = HeNEXT(entry);
1155 PERL_HASH_INTERNAL(hash, HeKEY(entry), HeKLEN(entry));
1160 = save_hek_flags(HeKEY(entry), HeKLEN(entry),
1161 hash, HeKFLAGS(entry));
1162 unshare_hek (HeKEY_hek(entry));
1163 HeKEY_hek(entry) = new_hek;
1165 /* Not shared, so simply write the new hash in. */
1166 HeHASH(entry) = hash;
1168 /*PerlIO_printf(PerlIO_stderr(), "%d ", HeKFLAGS(entry));*/
1169 HEK_REHASH_on(HeKEY_hek(entry));
1170 /*PerlIO_printf(PerlIO_stderr(), "%d\n", HeKFLAGS(entry));*/
1172 /* Copy oentry to the correct new chain. */
1173 bep = ((HE**)a) + (hash & (I32) xhv->xhv_max);
1175 xhv->xhv_fill++; /* HvFILL(hv)++ */
1176 HeNEXT(entry) = *bep;
1182 Safefree (xhv->xhv_array);
1183 xhv->xhv_array = a; /* HvARRAY(hv) = a */
1187 Perl_hv_ksplit(pTHX_ HV *hv, IV newmax)
1189 register XPVHV* xhv = (XPVHV*)SvANY(hv);
1190 I32 oldsize = (I32) xhv->xhv_max+1; /* HvMAX(hv)+1 (sick) */
1191 register I32 newsize;
1197 register HE **oentry;
1199 newsize = (I32) newmax; /* possible truncation here */
1200 if (newsize != newmax || newmax <= oldsize)
1202 while ((newsize & (1 + ~newsize)) != newsize) {
1203 newsize &= ~(newsize & (1 + ~newsize)); /* get proper power of 2 */
1205 if (newsize < newmax)
1207 if (newsize < newmax)
1208 return; /* overflow detection */
1210 a = xhv->xhv_array; /* HvARRAY(hv) */
1213 #if defined(STRANGE_MALLOC) || defined(MYMALLOC)
1214 Renew(a, PERL_HV_ARRAY_ALLOC_BYTES(newsize), char);
1220 New(2, a, PERL_HV_ARRAY_ALLOC_BYTES(newsize), char);
1225 Copy(xhv->xhv_array /* HvARRAY(hv) */, a, oldsize * sizeof(HE*), char);
1226 if (oldsize >= 64) {
1227 offer_nice_chunk(xhv->xhv_array /* HvARRAY(hv) */,
1228 PERL_HV_ARRAY_ALLOC_BYTES(oldsize));
1231 Safefree(xhv->xhv_array /* HvARRAY(hv) */);
1234 Zero(&a[oldsize * sizeof(HE*)], (newsize-oldsize) * sizeof(HE*), char); /* zero 2nd half*/
1237 Newz(0, a, PERL_HV_ARRAY_ALLOC_BYTES(newsize), char);
1239 xhv->xhv_max = --newsize; /* HvMAX(hv) = --newsize */
1240 xhv->xhv_array = a; /* HvARRAY(hv) = a */
1241 if (!xhv->xhv_fill /* !HvFILL(hv) */) /* skip rest if no entries */
1245 for (i=0; i<oldsize; i++,aep++) {
1246 if (!*aep) /* non-existent */
1248 for (oentry = aep, entry = *aep; entry; entry = *oentry) {
1249 if ((j = (HeHASH(entry) & newsize)) != i) {
1251 *oentry = HeNEXT(entry);
1252 if (!(HeNEXT(entry) = aep[j]))
1253 xhv->xhv_fill++; /* HvFILL(hv)++ */
1258 oentry = &HeNEXT(entry);
1260 if (!*aep) /* everything moved */
1261 xhv->xhv_fill--; /* HvFILL(hv)-- */
1268 Creates a new HV. The reference count is set to 1.
1277 register XPVHV* xhv;
1279 hv = (HV*)NEWSV(502,0);
1280 sv_upgrade((SV *)hv, SVt_PVHV);
1281 xhv = (XPVHV*)SvANY(hv);
1284 #ifndef NODEFAULT_SHAREKEYS
1285 HvSHAREKEYS_on(hv); /* key-sharing on by default */
1288 xhv->xhv_max = 7; /* HvMAX(hv) = 7 (start with 8 buckets) */
1289 xhv->xhv_fill = 0; /* HvFILL(hv) = 0 */
1290 xhv->xhv_pmroot = 0; /* HvPMROOT(hv) = 0 */
1291 (void)hv_iterinit(hv); /* so each() will start off right */
1296 Perl_newHVhv(pTHX_ HV *ohv)
1299 STRLEN hv_max, hv_fill;
1301 if (!ohv || (hv_fill = HvFILL(ohv)) == 0)
1303 hv_max = HvMAX(ohv);
1305 if (!SvMAGICAL((SV *)ohv)) {
1306 /* It's an ordinary hash, so copy it fast. AMS 20010804 */
1308 bool shared = !!HvSHAREKEYS(ohv);
1309 HE **ents, **oents = (HE **)HvARRAY(ohv);
1311 New(0, a, PERL_HV_ARRAY_ALLOC_BYTES(hv_max+1), char);
1314 /* In each bucket... */
1315 for (i = 0; i <= hv_max; i++) {
1316 HE *prev = NULL, *ent = NULL, *oent = oents[i];
1323 /* Copy the linked list of entries. */
1324 for (oent = oents[i]; oent; oent = HeNEXT(oent)) {
1325 U32 hash = HeHASH(oent);
1326 char *key = HeKEY(oent);
1327 STRLEN len = HeKLEN(oent);
1328 int flags = HeKFLAGS(oent);
1331 HeVAL(ent) = newSVsv(HeVAL(oent));
1333 = shared ? share_hek_flags(key, len, hash, flags)
1334 : save_hek_flags(key, len, hash, flags);
1345 HvFILL(hv) = hv_fill;
1346 HvTOTALKEYS(hv) = HvTOTALKEYS(ohv);
1350 /* Iterate over ohv, copying keys and values one at a time. */
1352 I32 riter = HvRITER(ohv);
1353 HE *eiter = HvEITER(ohv);
1355 /* Can we use fewer buckets? (hv_max is always 2^n-1) */
1356 while (hv_max && hv_max + 1 >= hv_fill * 2)
1357 hv_max = hv_max / 2;
1361 while ((entry = hv_iternext_flags(ohv, 0))) {
1362 hv_store_flags(hv, HeKEY(entry), HeKLEN(entry),
1363 newSVsv(HeVAL(entry)), HeHASH(entry),
1366 HvRITER(ohv) = riter;
1367 HvEITER(ohv) = eiter;
1374 Perl_hv_free_ent(pTHX_ HV *hv, register HE *entry)
1381 if (val && isGV(val) && GvCVu(val) && HvNAME(hv))
1382 PL_sub_generation++; /* may be deletion of method from stash */
1384 if (HeKLEN(entry) == HEf_SVKEY) {
1385 SvREFCNT_dec(HeKEY_sv(entry));
1386 Safefree(HeKEY_hek(entry));
1388 else if (HvSHAREKEYS(hv))
1389 unshare_hek(HeKEY_hek(entry));
1391 Safefree(HeKEY_hek(entry));
1396 Perl_hv_delayfree_ent(pTHX_ HV *hv, register HE *entry)
1400 if (isGV(HeVAL(entry)) && GvCVu(HeVAL(entry)) && HvNAME(hv))
1401 PL_sub_generation++; /* may be deletion of method from stash */
1402 sv_2mortal(HeVAL(entry)); /* free between statements */
1403 if (HeKLEN(entry) == HEf_SVKEY) {
1404 sv_2mortal(HeKEY_sv(entry));
1405 Safefree(HeKEY_hek(entry));
1407 else if (HvSHAREKEYS(hv))
1408 unshare_hek(HeKEY_hek(entry));
1410 Safefree(HeKEY_hek(entry));
1415 =for apidoc hv_clear
1417 Clears a hash, making it empty.
1423 Perl_hv_clear(pTHX_ HV *hv)
1425 register XPVHV* xhv;
1429 DEBUG_A(Perl_hv_assert(aTHX_ hv));
1431 xhv = (XPVHV*)SvANY(hv);
1433 if (SvREADONLY(hv) && xhv->xhv_array != NULL) {
1434 /* restricted hash: convert all keys to placeholders */
1437 for (i = 0; i <= (I32) xhv->xhv_max; i++) {
1438 entry = ((HE**)xhv->xhv_array)[i];
1439 for (; entry; entry = HeNEXT(entry)) {
1440 /* not already placeholder */
1441 if (HeVAL(entry) != &PL_sv_placeholder) {
1442 if (HeVAL(entry) && SvREADONLY(HeVAL(entry))) {
1443 SV* keysv = hv_iterkeysv(entry);
1445 "Attempt to delete readonly key '%"SVf"' from a restricted hash",
1448 SvREFCNT_dec(HeVAL(entry));
1449 HeVAL(entry) = &PL_sv_placeholder;
1450 xhv->xhv_placeholders++; /* HvPLACEHOLDERS(hv)++ */
1458 xhv->xhv_placeholders = 0; /* HvPLACEHOLDERS(hv) = 0 */
1459 if (xhv->xhv_array /* HvARRAY(hv) */)
1460 (void)memzero(xhv->xhv_array /* HvARRAY(hv) */,
1461 (xhv->xhv_max+1 /* HvMAX(hv)+1 */) * sizeof(HE*));
1466 HvHASKFLAGS_off(hv);
1473 =for apidoc hv_clear_placeholders
1475 Clears any placeholders from a hash. If a restricted hash has any of its keys
1476 marked as readonly and the key is subsequently deleted, the key is not actually
1477 deleted but is marked by assigning it a value of &PL_sv_placeholder. This tags
1478 it so it will be ignored by future operations such as iterating over the hash,
1479 but will still allow the hash to have a value reaasigned to the key at some
1480 future point. This function clears any such placeholder keys from the hash.
1481 See Hash::Util::lock_keys() for an example of its use.
1487 Perl_hv_clear_placeholders(pTHX_ HV *hv)
1489 I32 items = (I32)HvPLACEHOLDERS(hv);
1496 /* Loop down the linked list heads */
1498 HE **oentry = &(HvARRAY(hv))[i];
1499 HE *entry = *oentry;
1504 for (; entry; first=0, oentry = &HeNEXT(entry), entry = *oentry) {
1505 if (HeVAL(entry) == &PL_sv_placeholder) {
1506 *oentry = HeNEXT(entry);
1507 if (first && !*oentry)
1508 HvFILL(hv)--; /* This linked list is now empty. */
1512 hv_free_ent(hv, entry);
1516 HvTOTALKEYS(hv) -= HvPLACEHOLDERS(hv);
1517 if (HvKEYS(hv) == 0)
1518 HvHASKFLAGS_off(hv);
1519 HvPLACEHOLDERS(hv) = 0;
1525 /* You can't get here, hence assertion should always fail. */
1526 assert (items == 0);
1531 S_hfreeentries(pTHX_ HV *hv)
1533 register HE **array;
1535 register HE *oentry = Null(HE*);
1546 array = HvARRAY(hv);
1547 /* make everyone else think the array is empty, so that the destructors
1548 * called for freed entries can't recusively mess with us */
1549 HvARRAY(hv) = Null(HE**);
1551 ((XPVHV*) SvANY(hv))->xhv_keys = 0;
1557 entry = HeNEXT(entry);
1558 hv_free_ent(hv, oentry);
1563 entry = array[riter];
1566 HvARRAY(hv) = array;
1567 (void)hv_iterinit(hv);
1571 =for apidoc hv_undef
1579 Perl_hv_undef(pTHX_ HV *hv)
1581 register XPVHV* xhv;
1584 DEBUG_A(Perl_hv_assert(aTHX_ hv));
1585 xhv = (XPVHV*)SvANY(hv);
1587 Safefree(xhv->xhv_array /* HvARRAY(hv) */);
1590 hv_delete(PL_stashcache, HvNAME(hv), strlen(HvNAME(hv)), G_DISCARD);
1591 Safefree(HvNAME(hv));
1594 xhv->xhv_max = 7; /* HvMAX(hv) = 7 (it's a normal hash) */
1595 xhv->xhv_array = 0; /* HvARRAY(hv) = 0 */
1596 xhv->xhv_placeholders = 0; /* HvPLACEHOLDERS(hv) = 0 */
1603 =for apidoc hv_iterinit
1605 Prepares a starting point to traverse a hash table. Returns the number of
1606 keys in the hash (i.e. the same as C<HvKEYS(tb)>). The return value is
1607 currently only meaningful for hashes without tie magic.
1609 NOTE: Before version 5.004_65, C<hv_iterinit> used to return the number of
1610 hash buckets that happen to be in use. If you still need that esoteric
1611 value, you can get it through the macro C<HvFILL(tb)>.
1618 Perl_hv_iterinit(pTHX_ HV *hv)
1620 register XPVHV* xhv;
1624 Perl_croak(aTHX_ "Bad hash");
1625 xhv = (XPVHV*)SvANY(hv);
1626 entry = xhv->xhv_eiter; /* HvEITER(hv) */
1627 if (entry && HvLAZYDEL(hv)) { /* was deleted earlier? */
1629 hv_free_ent(hv, entry);
1631 xhv->xhv_riter = -1; /* HvRITER(hv) = -1 */
1632 xhv->xhv_eiter = Null(HE*); /* HvEITER(hv) = Null(HE*) */
1633 /* used to be xhv->xhv_fill before 5.004_65 */
1634 return XHvTOTALKEYS(xhv);
1637 =for apidoc hv_iternext
1639 Returns entries from a hash iterator. See C<hv_iterinit>.
1641 You may call C<hv_delete> or C<hv_delete_ent> on the hash entry that the
1642 iterator currently points to, without losing your place or invalidating your
1643 iterator. Note that in this case the current entry is deleted from the hash
1644 with your iterator holding the last reference to it. Your iterator is flagged
1645 to free the entry on the next call to C<hv_iternext>, so you must not discard
1646 your iterator immediately else the entry will leak - call C<hv_iternext> to
1647 trigger the resource deallocation.
1653 Perl_hv_iternext(pTHX_ HV *hv)
1655 return hv_iternext_flags(hv, 0);
1659 =for apidoc hv_iternext_flags
1661 Returns entries from a hash iterator. See C<hv_iterinit> and C<hv_iternext>.
1662 The C<flags> value will normally be zero; if HV_ITERNEXT_WANTPLACEHOLDERS is
1663 set the placeholders keys (for restricted hashes) will be returned in addition
1664 to normal keys. By default placeholders are automatically skipped over.
1665 Currently a placeholder is implemented with a value that is
1666 C<&Perl_sv_placeholder>. Note that the implementation of placeholders and
1667 restricted hashes may change, and the implementation currently is
1668 insufficiently abstracted for any change to be tidy.
1674 Perl_hv_iternext_flags(pTHX_ HV *hv, I32 flags)
1676 register XPVHV* xhv;
1682 Perl_croak(aTHX_ "Bad hash");
1683 xhv = (XPVHV*)SvANY(hv);
1684 oldentry = entry = xhv->xhv_eiter; /* HvEITER(hv) */
1686 if ((mg = SvTIED_mg((SV*)hv, PERL_MAGIC_tied))) {
1687 SV *key = sv_newmortal();
1689 sv_setsv(key, HeSVKEY_force(entry));
1690 SvREFCNT_dec(HeSVKEY(entry)); /* get rid of previous key */
1696 /* one HE per MAGICAL hash */
1697 xhv->xhv_eiter = entry = new_HE(); /* HvEITER(hv) = new_HE() */
1699 Newz(54, k, HEK_BASESIZE + sizeof(SV*), char);
1701 HeKEY_hek(entry) = hek;
1702 HeKLEN(entry) = HEf_SVKEY;
1704 magic_nextpack((SV*) hv,mg,key);
1706 /* force key to stay around until next time */
1707 HeSVKEY_set(entry, SvREFCNT_inc(key));
1708 return entry; /* beware, hent_val is not set */
1711 SvREFCNT_dec(HeVAL(entry));
1712 Safefree(HeKEY_hek(entry));
1714 xhv->xhv_eiter = Null(HE*); /* HvEITER(hv) = Null(HE*) */
1717 #ifdef DYNAMIC_ENV_FETCH /* set up %ENV for iteration */
1718 if (!entry && SvRMAGICAL((SV*)hv) && mg_find((SV*)hv, PERL_MAGIC_env))
1722 if (!xhv->xhv_array /* !HvARRAY(hv) */)
1723 Newz(506, xhv->xhv_array /* HvARRAY(hv) */,
1724 PERL_HV_ARRAY_ALLOC_BYTES(xhv->xhv_max+1 /* HvMAX(hv)+1 */),
1726 /* At start of hash, entry is NULL. */
1729 entry = HeNEXT(entry);
1730 if (!(flags & HV_ITERNEXT_WANTPLACEHOLDERS)) {
1732 * Skip past any placeholders -- don't want to include them in
1735 while (entry && HeVAL(entry) == &PL_sv_placeholder) {
1736 entry = HeNEXT(entry);
1741 /* OK. Come to the end of the current list. Grab the next one. */
1743 xhv->xhv_riter++; /* HvRITER(hv)++ */
1744 if (xhv->xhv_riter > (I32)xhv->xhv_max /* HvRITER(hv) > HvMAX(hv) */) {
1745 /* There is no next one. End of the hash. */
1746 xhv->xhv_riter = -1; /* HvRITER(hv) = -1 */
1749 /* entry = (HvARRAY(hv))[HvRITER(hv)]; */
1750 entry = ((HE**)xhv->xhv_array)[xhv->xhv_riter];
1752 if (!(flags & HV_ITERNEXT_WANTPLACEHOLDERS)) {
1753 /* If we have an entry, but it's a placeholder, don't count it.
1755 while (entry && HeVAL(entry) == &PL_sv_placeholder)
1756 entry = HeNEXT(entry);
1758 /* Will loop again if this linked list starts NULL
1759 (for HV_ITERNEXT_WANTPLACEHOLDERS)
1760 or if we run through it and find only placeholders. */
1763 if (oldentry && HvLAZYDEL(hv)) { /* was deleted earlier? */
1765 hv_free_ent(hv, oldentry);
1768 /*if (HvREHASH(hv) && entry && !HeKREHASH(entry))
1769 PerlIO_printf(PerlIO_stderr(), "Awooga %p %p\n", hv, entry);*/
1771 xhv->xhv_eiter = entry; /* HvEITER(hv) = entry */
1776 =for apidoc hv_iterkey
1778 Returns the key from the current position of the hash iterator. See
1785 Perl_hv_iterkey(pTHX_ register HE *entry, I32 *retlen)
1787 if (HeKLEN(entry) == HEf_SVKEY) {
1789 char *p = SvPV(HeKEY_sv(entry), len);
1794 *retlen = HeKLEN(entry);
1795 return HeKEY(entry);
1799 /* unlike hv_iterval(), this always returns a mortal copy of the key */
1801 =for apidoc hv_iterkeysv
1803 Returns the key as an C<SV*> from the current position of the hash
1804 iterator. The return value will always be a mortal copy of the key. Also
1811 Perl_hv_iterkeysv(pTHX_ register HE *entry)
1813 if (HeKLEN(entry) != HEf_SVKEY) {
1814 HEK *hek = HeKEY_hek(entry);
1815 int flags = HEK_FLAGS(hek);
1818 if (flags & HVhek_WASUTF8) {
1820 Andreas would like keys he put in as utf8 to come back as utf8
1822 STRLEN utf8_len = HEK_LEN(hek);
1823 U8 *as_utf8 = bytes_to_utf8 ((U8*)HEK_KEY(hek), &utf8_len);
1825 sv = newSVpvn ((char*)as_utf8, utf8_len);
1827 Safefree (as_utf8); /* bytes_to_utf8() allocates a new string */
1828 } else if (flags & HVhek_REHASH) {
1829 /* We don't have a pointer to the hv, so we have to replicate the
1830 flag into every HEK. This hv is using custom a hasing
1831 algorithm. Hence we can't return a shared string scalar, as
1832 that would contain the (wrong) hash value, and might get passed
1833 into an hv routine with a regular hash */
1835 sv = newSVpvn (HEK_KEY(hek), HEK_LEN(hek));
1839 sv = newSVpvn_share(HEK_KEY(hek),
1840 (HEK_UTF8(hek) ? -HEK_LEN(hek) : HEK_LEN(hek)),
1843 return sv_2mortal(sv);
1845 return sv_mortalcopy(HeKEY_sv(entry));
1849 =for apidoc hv_iterval
1851 Returns the value from the current position of the hash iterator. See
1858 Perl_hv_iterval(pTHX_ HV *hv, register HE *entry)
1860 if (SvRMAGICAL(hv)) {
1861 if (mg_find((SV*)hv, PERL_MAGIC_tied)) {
1862 SV* sv = sv_newmortal();
1863 if (HeKLEN(entry) == HEf_SVKEY)
1864 mg_copy((SV*)hv, sv, (char*)HeKEY_sv(entry), HEf_SVKEY);
1865 else mg_copy((SV*)hv, sv, HeKEY(entry), HeKLEN(entry));
1869 return HeVAL(entry);
1873 =for apidoc hv_iternextsv
1875 Performs an C<hv_iternext>, C<hv_iterkey>, and C<hv_iterval> in one
1882 Perl_hv_iternextsv(pTHX_ HV *hv, char **key, I32 *retlen)
1885 if ( (he = hv_iternext_flags(hv, 0)) == NULL)
1887 *key = hv_iterkey(he, retlen);
1888 return hv_iterval(hv, he);
1892 =for apidoc hv_magic
1894 Adds magic to a hash. See C<sv_magic>.
1900 Perl_hv_magic(pTHX_ HV *hv, GV *gv, int how)
1902 sv_magic((SV*)hv, (SV*)gv, how, Nullch, 0);
1905 #if 0 /* use the macro from hv.h instead */
1908 Perl_sharepvn(pTHX_ const char *sv, I32 len, U32 hash)
1910 return HEK_KEY(share_hek(sv, len, hash));
1915 /* possibly free a shared string if no one has access to it
1916 * len and hash must both be valid for str.
1919 Perl_unsharepvn(pTHX_ const char *str, I32 len, U32 hash)
1921 unshare_hek_or_pvn (NULL, str, len, hash);
1926 Perl_unshare_hek(pTHX_ HEK *hek)
1928 unshare_hek_or_pvn(hek, NULL, 0, 0);
1931 /* possibly free a shared string if no one has access to it
1932 hek if non-NULL takes priority over the other 3, else str, len and hash
1933 are used. If so, len and hash must both be valid for str.
1936 S_unshare_hek_or_pvn(pTHX_ HEK *hek, const char *str, I32 len, U32 hash)
1938 register XPVHV* xhv;
1940 register HE **oentry;
1943 bool is_utf8 = FALSE;
1945 const char *save = str;
1948 hash = HEK_HASH(hek);
1949 } else if (len < 0) {
1950 STRLEN tmplen = -len;
1952 /* See the note in hv_fetch(). --jhi */
1953 str = (char*)bytes_from_utf8((U8*)str, &tmplen, &is_utf8);
1956 k_flags = HVhek_UTF8;
1958 k_flags |= HVhek_WASUTF8 | HVhek_FREEKEY;
1961 /* what follows is the moral equivalent of:
1962 if ((Svp = hv_fetch(PL_strtab, tmpsv, FALSE, hash))) {
1963 if (--*Svp == Nullsv)
1964 hv_delete(PL_strtab, str, len, G_DISCARD, hash);
1966 xhv = (XPVHV*)SvANY(PL_strtab);
1967 /* assert(xhv_array != 0) */
1969 /* oentry = &(HvARRAY(hv))[hash & (I32) HvMAX(hv)]; */
1970 oentry = &((HE**)xhv->xhv_array)[hash & (I32) xhv->xhv_max];
1972 for (entry = *oentry; entry; i=0, oentry = &HeNEXT(entry), entry = *oentry) {
1973 if (HeKEY_hek(entry) != hek)
1979 int flags_masked = k_flags & HVhek_MASK;
1980 for (entry = *oentry; entry; i=0, oentry = &HeNEXT(entry), entry = *oentry) {
1981 if (HeHASH(entry) != hash) /* strings can't be equal */
1983 if (HeKLEN(entry) != len)
1985 if (HeKEY(entry) != str && memNE(HeKEY(entry),str,len)) /* is this it? */
1987 if (HeKFLAGS(entry) != flags_masked)
1995 if (--HeVAL(entry) == Nullsv) {
1996 *oentry = HeNEXT(entry);
1998 xhv->xhv_fill--; /* HvFILL(hv)-- */
1999 Safefree(HeKEY_hek(entry));
2001 xhv->xhv_keys--; /* HvKEYS(hv)-- */
2005 UNLOCK_STRTAB_MUTEX;
2006 if (!found && ckWARN_d(WARN_INTERNAL))
2007 Perl_warner(aTHX_ packWARN(WARN_INTERNAL),
2008 "Attempt to free non-existent shared string '%s'%s",
2009 hek ? HEK_KEY(hek) : str,
2010 (k_flags & HVhek_UTF8) ? " (utf8)" : "");
2011 if (k_flags & HVhek_FREEKEY)
2015 /* get a (constant) string ptr from the global string table
2016 * string will get added if it is not already there.
2017 * len and hash must both be valid for str.
2020 Perl_share_hek(pTHX_ const char *str, I32 len, register U32 hash)
2022 bool is_utf8 = FALSE;
2024 const char *save = str;
2027 STRLEN tmplen = -len;
2029 /* See the note in hv_fetch(). --jhi */
2030 str = (char*)bytes_from_utf8((U8*)str, &tmplen, &is_utf8);
2032 /* If we were able to downgrade here, then than means that we were passed
2033 in a key which only had chars 0-255, but was utf8 encoded. */
2036 /* If we found we were able to downgrade the string to bytes, then
2037 we should flag that it needs upgrading on keys or each. Also flag
2038 that we need share_hek_flags to free the string. */
2040 flags |= HVhek_WASUTF8 | HVhek_FREEKEY;
2043 return share_hek_flags (str, len, hash, flags);
2047 S_share_hek_flags(pTHX_ const char *str, I32 len, register U32 hash, int flags)
2049 register XPVHV* xhv;
2051 register HE **oentry;
2054 int flags_masked = flags & HVhek_MASK;
2056 /* what follows is the moral equivalent of:
2058 if (!(Svp = hv_fetch(PL_strtab, str, len, FALSE)))
2059 hv_store(PL_strtab, str, len, Nullsv, hash);
2061 Can't rehash the shared string table, so not sure if it's worth
2062 counting the number of entries in the linked list
2064 xhv = (XPVHV*)SvANY(PL_strtab);
2065 /* assert(xhv_array != 0) */
2067 /* oentry = &(HvARRAY(hv))[hash & (I32) HvMAX(hv)]; */
2068 oentry = &((HE**)xhv->xhv_array)[hash & (I32) xhv->xhv_max];
2069 for (entry = *oentry; entry; i=0, entry = HeNEXT(entry)) {
2070 if (HeHASH(entry) != hash) /* strings can't be equal */
2072 if (HeKLEN(entry) != len)
2074 if (HeKEY(entry) != str && memNE(HeKEY(entry),str,len)) /* is this it? */
2076 if (HeKFLAGS(entry) != flags_masked)
2083 HeKEY_hek(entry) = save_hek_flags(str, len, hash, flags_masked);
2084 HeVAL(entry) = Nullsv;
2085 HeNEXT(entry) = *oentry;
2087 xhv->xhv_keys++; /* HvKEYS(hv)++ */
2088 if (i) { /* initial entry? */
2089 xhv->xhv_fill++; /* HvFILL(hv)++ */
2090 } else if (xhv->xhv_keys > (IV)xhv->xhv_max /* HvKEYS(hv) > HvMAX(hv) */) {
2095 ++HeVAL(entry); /* use value slot as REFCNT */
2096 UNLOCK_STRTAB_MUTEX;
2098 if (flags & HVhek_FREEKEY)
2101 return HeKEY_hek(entry);
2106 =for apidoc hv_assert
2108 Check that a hash is in an internally consistent state.
2114 Perl_hv_assert(pTHX_ HV *hv)
2118 int placeholders = 0;
2121 I32 riter = HvRITER(hv);
2122 HE *eiter = HvEITER(hv);
2124 (void)hv_iterinit(hv);
2126 while ((entry = hv_iternext_flags(hv, HV_ITERNEXT_WANTPLACEHOLDERS))) {
2127 /* sanity check the values */
2128 if (HeVAL(entry) == &PL_sv_placeholder) {
2133 /* sanity check the keys */
2134 if (HeSVKEY(entry)) {
2135 /* Don't know what to check on SV keys. */
2136 } else if (HeKUTF8(entry)) {
2138 if (HeKWASUTF8(entry)) {
2139 PerlIO_printf(Perl_debug_log,
2140 "hash key has both WASUFT8 and UTF8: '%.*s'\n",
2141 (int) HeKLEN(entry), HeKEY(entry));
2144 } else if (HeKWASUTF8(entry)) {
2148 if (!SvTIED_mg((SV*)hv, PERL_MAGIC_tied)) {
2149 if (HvUSEDKEYS(hv) != real) {
2150 PerlIO_printf(Perl_debug_log, "Count %d key(s), but hash reports %d\n",
2151 (int) real, (int) HvUSEDKEYS(hv));
2154 if (HvPLACEHOLDERS(hv) != placeholders) {
2155 PerlIO_printf(Perl_debug_log,
2156 "Count %d placeholder(s), but hash reports %d\n",
2157 (int) placeholders, (int) HvPLACEHOLDERS(hv));
2161 if (withflags && ! HvHASKFLAGS(hv)) {
2162 PerlIO_printf(Perl_debug_log,
2163 "Hash has HASKFLAGS off but I count %d key(s) with flags\n",
2170 HvRITER(hv) = riter; /* Restore hash iterator state */
2171 HvEITER(hv) = eiter;