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)
86 New(54, k, HEK_BASESIZE + len + 2, char);
88 Copy(str, HEK_KEY(hek), len, char);
89 HEK_KEY(hek)[len] = 0;
92 HEK_FLAGS(hek) = (unsigned char)flags;
96 /* free the pool of temporary HE/HEK pairs retunrned by hv_fetch_ent
100 Perl_free_tied_hv_pool(pTHX)
103 HE *he = PL_hv_fetch_ent_mh;
105 Safefree(HeKEY_hek(he));
110 PL_hv_fetch_ent_mh = Nullhe;
113 #if defined(USE_ITHREADS)
115 Perl_he_dup(pTHX_ HE *e, bool shared, CLONE_PARAMS* param)
121 /* look for it in the table first */
122 ret = (HE*)ptr_table_fetch(PL_ptr_table, e);
126 /* create anew and remember what it is */
128 ptr_table_store(PL_ptr_table, e, ret);
130 HeNEXT(ret) = he_dup(HeNEXT(e),shared, param);
131 if (HeKLEN(e) == HEf_SVKEY) {
133 New(54, k, HEK_BASESIZE + sizeof(SV*), char);
134 HeKEY_hek(ret) = (HEK*)k;
135 HeKEY_sv(ret) = SvREFCNT_inc(sv_dup(HeKEY_sv(e), param));
138 HeKEY_hek(ret) = share_hek_flags(HeKEY(e), HeKLEN(e), HeHASH(e),
141 HeKEY_hek(ret) = save_hek_flags(HeKEY(e), HeKLEN(e), HeHASH(e),
143 HeVAL(ret) = SvREFCNT_inc(sv_dup(HeVAL(e), param));
146 #endif /* USE_ITHREADS */
149 S_hv_notallowed(pTHX_ int flags, const char *key, I32 klen,
152 SV *sv = sv_newmortal(), *esv = sv_newmortal();
153 if (!(flags & HVhek_FREEKEY)) {
154 sv_setpvn(sv, key, klen);
157 /* Need to free saved eventually assign to mortal SV */
158 /* XXX is this line an error ???: SV *sv = sv_newmortal(); */
159 sv_usepvn(sv, (char *) key, klen);
161 if (flags & HVhek_UTF8) {
164 Perl_sv_setpvf(aTHX_ esv, "Attempt to %s a restricted hash", msg);
165 Perl_croak(aTHX_ SvPVX(esv), sv);
168 /* (klen == HEf_SVKEY) is special for MAGICAL hv entries, meaning key slot
171 #define HV_FETCH_ISSTORE 0x01
172 #define HV_FETCH_ISEXISTS 0x02
173 #define HV_FETCH_LVALUE 0x04
174 #define HV_FETCH_JUST_SV 0x08
179 Stores an SV in a hash. The hash key is specified as C<key> and C<klen> is
180 the length of the key. The C<hash> parameter is the precomputed hash
181 value; if it is zero then Perl will compute it. The return value will be
182 NULL if the operation failed or if the value did not need to be actually
183 stored within the hash (as in the case of tied hashes). Otherwise it can
184 be dereferenced to get the original C<SV*>. Note that the caller is
185 responsible for suitably incrementing the reference count of C<val> before
186 the call, and decrementing it if the function returned NULL. Effectively
187 a successful hv_store takes ownership of one reference to C<val>. This is
188 usually what you want; a newly created SV has a reference count of one, so
189 if all your code does is create SVs then store them in a hash, hv_store
190 will own the only reference to the new SV, and your code doesn't need to do
191 anything further to tidy up. hv_store is not implemented as a call to
192 hv_store_ent, and does not create a temporary SV for the key, so if your
193 key data is not already in SV form then use hv_store in preference to
196 See L<perlguts/"Understanding the Magic of Tied Hashes and Arrays"> for more
197 information on how to use this function on tied hashes.
203 Perl_hv_store(pTHX_ HV *hv, const char *key, I32 klen_i32, SV *val, U32 hash)
216 hek = hv_fetch_common (hv, NULL, key, klen, flags,
217 (HV_FETCH_ISSTORE|HV_FETCH_JUST_SV), val, 0);
218 return hek ? &HeVAL(hek) : NULL;
222 Perl_hv_store_flags(pTHX_ HV *hv, const char *key, I32 klen, SV *val,
223 register U32 hash, int flags)
225 HE *hek = hv_fetch_common (hv, NULL, key, klen, flags,
226 (HV_FETCH_ISSTORE|HV_FETCH_JUST_SV), val, hash);
227 return hek ? &HeVAL(hek) : NULL;
231 =for apidoc hv_store_ent
233 Stores C<val> in a hash. The hash key is specified as C<key>. The C<hash>
234 parameter is the precomputed hash value; if it is zero then Perl will
235 compute it. The return value is the new hash entry so created. It will be
236 NULL if the operation failed or if the value did not need to be actually
237 stored within the hash (as in the case of tied hashes). Otherwise the
238 contents of the return value can be accessed using the C<He?> macros
239 described here. Note that the caller is responsible for suitably
240 incrementing the reference count of C<val> before the call, and
241 decrementing it if the function returned NULL. Effectively a successful
242 hv_store_ent takes ownership of one reference to C<val>. This is
243 usually what you want; a newly created SV has a reference count of one, so
244 if all your code does is create SVs then store them in a hash, hv_store
245 will own the only reference to the new SV, and your code doesn't need to do
246 anything further to tidy up. Note that hv_store_ent only reads the C<key>;
247 unlike C<val> it does not take ownership of it, so maintaining the correct
248 reference count on C<key> is entirely the caller's responsibility. hv_store
249 is not implemented as a call to hv_store_ent, and does not create a temporary
250 SV for the key, so if your key data is not already in SV form then use
251 hv_store in preference to hv_store_ent.
253 See L<perlguts/"Understanding the Magic of Tied Hashes and Arrays"> for more
254 information on how to use this function on tied hashes.
260 Perl_hv_store_ent(pTHX_ HV *hv, SV *keysv, SV *val, U32 hash)
262 return hv_fetch_common(hv, keysv, NULL, 0, 0, HV_FETCH_ISSTORE, val, hash);
266 =for apidoc hv_exists
268 Returns a boolean indicating whether the specified hash key exists. The
269 C<klen> is the length of the key.
275 Perl_hv_exists(pTHX_ HV *hv, const char *key, I32 klen_i32)
287 return hv_fetch_common(hv, NULL, key, klen, flags, HV_FETCH_ISEXISTS, 0, 0)
294 Returns the SV which corresponds to the specified key in the hash. The
295 C<klen> is the length of the key. If C<lval> is set then the fetch will be
296 part of a store. Check that the return value is non-null before
297 dereferencing it to an C<SV*>.
299 See L<perlguts/"Understanding the Magic of Tied Hashes and Arrays"> for more
300 information on how to use this function on tied hashes.
306 Perl_hv_fetch(pTHX_ HV *hv, const char *key, I32 klen_i32, I32 lval)
319 hek = hv_fetch_common (hv, NULL, key, klen, flags,
320 HV_FETCH_JUST_SV | (lval ? HV_FETCH_LVALUE : 0),
322 return hek ? &HeVAL(hek) : NULL;
326 =for apidoc hv_exists_ent
328 Returns a boolean indicating whether the specified hash key exists. C<hash>
329 can be a valid precomputed hash value, or 0 to ask for it to be
336 Perl_hv_exists_ent(pTHX_ HV *hv, SV *keysv, U32 hash)
338 return hv_fetch_common(hv, keysv, NULL, 0, 0, HV_FETCH_ISEXISTS, 0, hash)
342 /* returns an HE * structure with the all fields set */
343 /* note that hent_val will be a mortal sv for MAGICAL hashes */
345 =for apidoc hv_fetch_ent
347 Returns the hash entry which corresponds to the specified key in the hash.
348 C<hash> must be a valid precomputed hash number for the given C<key>, or 0
349 if you want the function to compute it. IF C<lval> is set then the fetch
350 will be part of a store. Make sure the return value is non-null before
351 accessing it. The return value when C<tb> is a tied hash is a pointer to a
352 static location, so be sure to make a copy of the structure if you need to
355 See L<perlguts/"Understanding the Magic of Tied Hashes and Arrays"> for more
356 information on how to use this function on tied hashes.
362 Perl_hv_fetch_ent(pTHX_ HV *hv, SV *keysv, I32 lval, register U32 hash)
364 return hv_fetch_common(hv, keysv, NULL, 0, 0,
365 (lval ? HV_FETCH_LVALUE : 0), Nullsv, hash);
369 S_hv_fetch_common(pTHX_ HV *hv, SV *keysv, const char *key, STRLEN klen,
370 int flags, int action, SV *val, register U32 hash)
384 if (flags & HVhek_FREEKEY)
386 key = SvPV(keysv, klen);
388 is_utf8 = (SvUTF8(keysv) != 0);
390 is_utf8 = ((flags & HVhek_UTF8) ? TRUE : FALSE);
393 xhv = (XPVHV*)SvANY(hv);
395 if (SvRMAGICAL(hv) && !(action & (HV_FETCH_ISSTORE|HV_FETCH_ISEXISTS)))
397 if (mg_find((SV*)hv, PERL_MAGIC_tied) || SvGMAGICAL((SV*)hv)) {
400 /* XXX should be able to skimp on the HE/HEK here when
401 HV_FETCH_JUST_SV is true. */
404 keysv = newSVpvn(key, klen);
409 keysv = newSVsv(keysv);
411 mg_copy((SV*)hv, sv, (char *)keysv, HEf_SVKEY);
413 /* grab a fake HE/HEK pair from the pool or make a new one */
414 entry = PL_hv_fetch_ent_mh;
416 PL_hv_fetch_ent_mh = HeNEXT(entry);
420 New(54, k, HEK_BASESIZE + sizeof(SV*), char);
421 HeKEY_hek(entry) = (HEK*)k;
423 HeNEXT(entry) = Nullhe;
424 HeSVKEY_set(entry, keysv);
426 sv_upgrade(sv, SVt_PVLV);
428 /* so we can free entry when freeing sv */
429 LvTARG(sv) = (SV*)entry;
431 /* XXX remove at some point? */
432 if (flags & HVhek_FREEKEY)
437 #ifdef ENV_IS_CASELESS
438 else if (mg_find((SV*)hv, PERL_MAGIC_env)) {
440 for (i = 0; i < klen; ++i)
441 if (isLOWER(key[i])) {
442 /* Would be nice if we had a routine to do the
443 copy and upercase in a single pass through. */
444 char *nkey = strupr(savepvn(key,klen));
445 /* Note that this fetch is for nkey (the uppercased
446 key) whereas the store is for key (the original) */
447 entry = hv_fetch_common(hv, Nullsv, nkey, klen,
448 HVhek_FREEKEY, /* free nkey */
449 0 /* non-LVAL fetch */,
450 Nullsv /* no value */,
451 0 /* compute hash */);
452 if (!entry && (action & HV_FETCH_LVALUE)) {
453 /* This call will free key if necessary.
454 Do it this way to encourage compiler to tail
456 entry = hv_fetch_common(hv, keysv, key, klen,
457 flags, HV_FETCH_ISSTORE,
460 if (flags & HVhek_FREEKEY)
468 else if (SvRMAGICAL(hv) && (action & HV_FETCH_ISEXISTS)) {
469 if (mg_find((SV*)hv, PERL_MAGIC_tied) || SvGMAGICAL((SV*)hv)) {
471 /* I don't understand why hv_exists_ent has svret and sv,
472 whereas hv_exists only had one. */
473 svret = sv_newmortal();
476 if (keysv || is_utf8) {
478 keysv = newSVpvn(key, klen);
481 keysv = newSVsv(keysv);
483 mg_copy((SV*)hv, sv, (char *)sv_2mortal(keysv), HEf_SVKEY);
485 mg_copy((SV*)hv, sv, key, klen);
487 if (flags & HVhek_FREEKEY)
489 magic_existspack(svret, mg_find(sv, PERL_MAGIC_tiedelem));
490 /* This cast somewhat evil, but I'm merely using NULL/
491 not NULL to return the boolean exists.
492 And I know hv is not NULL. */
493 return SvTRUE(svret) ? (HE *)hv : NULL;
495 #ifdef ENV_IS_CASELESS
496 else if (mg_find((SV*)hv, PERL_MAGIC_env)) {
497 /* XXX This code isn't UTF8 clean. */
498 const char *keysave = key;
499 /* Will need to free this, so set FREEKEY flag. */
500 key = savepvn(key,klen);
501 key = (const char*)strupr((char*)key);
505 if (flags & HVhek_FREEKEY) {
508 flags |= HVhek_FREEKEY;
512 else if (action & HV_FETCH_ISSTORE) {
515 hv_magic_check (hv, &needs_copy, &needs_store);
517 bool save_taint = PL_tainted;
518 if (keysv || is_utf8) {
520 keysv = newSVpvn(key, klen);
524 PL_tainted = SvTAINTED(keysv);
525 keysv = sv_2mortal(newSVsv(keysv));
526 mg_copy((SV*)hv, val, (char*)keysv, HEf_SVKEY);
528 mg_copy((SV*)hv, val, key, klen);
531 TAINT_IF(save_taint);
532 if (!xhv->xhv_array /* !HvARRAY(hv) */ && !needs_store) {
533 if (flags & HVhek_FREEKEY)
537 #ifdef ENV_IS_CASELESS
538 else if (mg_find((SV*)hv, PERL_MAGIC_env)) {
539 /* XXX This code isn't UTF8 clean. */
540 const char *keysave = key;
541 /* Will need to free this, so set FREEKEY flag. */
542 key = savepvn(key,klen);
543 key = (const char*)strupr((char*)key);
547 if (flags & HVhek_FREEKEY) {
550 flags |= HVhek_FREEKEY;
557 if (!xhv->xhv_array /* !HvARRAY(hv) */) {
558 if ((action & (HV_FETCH_LVALUE | HV_FETCH_ISSTORE))
559 #ifdef DYNAMIC_ENV_FETCH /* if it's an %ENV lookup, we may get it on the fly */
560 || (SvRMAGICAL((SV*)hv) && mg_find((SV*)hv, PERL_MAGIC_env))
563 Newz(503, xhv->xhv_array /* HvARRAY(hv) */,
564 PERL_HV_ARRAY_ALLOC_BYTES(xhv->xhv_max+1 /* HvMAX(hv)+1 */),
566 #ifdef DYNAMIC_ENV_FETCH
567 else if (action & HV_FETCH_ISEXISTS) {
568 /* for an %ENV exists, if we do an insert it's by a recursive
569 store call, so avoid creating HvARRAY(hv) right now. */
573 /* XXX remove at some point? */
574 if (flags & HVhek_FREEKEY)
582 const char *keysave = key;
583 key = (char*)bytes_from_utf8((U8*)key, &klen, &is_utf8);
587 flags &= ~HVhek_UTF8;
588 if (key != keysave) {
589 if (flags & HVhek_FREEKEY)
591 flags |= HVhek_WASUTF8 | HVhek_FREEKEY;
596 PERL_HASH_INTERNAL(hash, key, klen);
597 /* We don't have a pointer to the hv, so we have to replicate the
598 flag into every HEK, so that hv_iterkeysv can see it. */
599 /* And yes, you do need this even though you are not "storing" because
600 you can flip the flags below if doing an lval lookup. (And that
601 was put in to give the semantics Andreas was expecting.) */
602 flags |= HVhek_REHASH;
604 if (keysv && (SvIsCOW_shared_hash(keysv))) {
607 PERL_HASH(hash, key, klen);
611 masked_flags = (flags & HVhek_MASK);
614 #ifdef DYNAMIC_ENV_FETCH
615 if (!xhv->xhv_array /* !HvARRAY(hv) */) entry = Null(HE*);
619 /* entry = (HvARRAY(hv))[hash & (I32) HvMAX(hv)]; */
620 entry = ((HE**)xhv->xhv_array)[hash & (I32) xhv->xhv_max];
622 for (; entry; ++n_links, entry = HeNEXT(entry)) {
623 if (HeHASH(entry) != hash) /* strings can't be equal */
625 if (HeKLEN(entry) != (I32)klen)
627 if (HeKEY(entry) != key && memNE(HeKEY(entry),key,klen)) /* is this it? */
629 if ((HeKFLAGS(entry) ^ masked_flags) & HVhek_UTF8)
632 if (action & (HV_FETCH_LVALUE|HV_FETCH_ISSTORE)) {
633 if (HeKFLAGS(entry) != masked_flags) {
634 /* We match if HVhek_UTF8 bit in our flags and hash key's
635 match. But if entry was set previously with HVhek_WASUTF8
636 and key now doesn't (or vice versa) then we should change
637 the key's flag, as this is assignment. */
638 if (HvSHAREKEYS(hv)) {
639 /* Need to swap the key we have for a key with the flags we
640 need. As keys are shared we can't just write to the
641 flag, so we share the new one, unshare the old one. */
642 HEK *new_hek = share_hek_flags(key, klen, hash,
644 unshare_hek (HeKEY_hek(entry));
645 HeKEY_hek(entry) = new_hek;
648 HeKFLAGS(entry) = masked_flags;
649 if (masked_flags & HVhek_ENABLEHVKFLAGS)
652 if (HeVAL(entry) == &PL_sv_placeholder) {
653 /* yes, can store into placeholder slot */
654 if (action & HV_FETCH_LVALUE) {
656 /* This preserves behaviour with the old hv_fetch
657 implementation which at this point would bail out
658 with a break; (at "if we find a placeholder, we
659 pretend we haven't found anything")
661 That break mean that if a placeholder were found, it
662 caused a call into hv_store, which in turn would
663 check magic, and if there is no magic end up pretty
664 much back at this point (in hv_store's code). */
667 /* LVAL fetch which actaully needs a store. */
669 xhv->xhv_placeholders--;
672 if (val != &PL_sv_placeholder)
673 xhv->xhv_placeholders--;
676 } else if (action & HV_FETCH_ISSTORE) {
677 SvREFCNT_dec(HeVAL(entry));
680 } else if (HeVAL(entry) == &PL_sv_placeholder) {
681 /* if we find a placeholder, we pretend we haven't found
685 if (flags & HVhek_FREEKEY)
689 #ifdef DYNAMIC_ENV_FETCH /* %ENV lookup? If so, try to fetch the value now */
690 if (!(action & HV_FETCH_ISSTORE)
691 && SvRMAGICAL((SV*)hv) && mg_find((SV*)hv, PERL_MAGIC_env)) {
693 char *env = PerlEnv_ENVgetenv_len(key,&len);
695 sv = newSVpvn(env,len);
697 return hv_fetch_common(hv,keysv,key,klen,flags,HV_FETCH_ISSTORE,sv,
703 if (!entry && SvREADONLY(hv) && !(action & HV_FETCH_ISEXISTS)) {
704 S_hv_notallowed(aTHX_ flags, key, klen,
705 "access disallowed key '%"SVf"' in"
708 if (!(action & (HV_FETCH_LVALUE|HV_FETCH_ISSTORE))) {
709 /* Not doing some form of store, so return failure. */
710 if (flags & HVhek_FREEKEY)
714 if (action & HV_FETCH_LVALUE) {
717 /* At this point the old hv_fetch code would call to hv_store,
718 which in turn might do some tied magic. So we need to make that
719 magic check happen. */
720 /* gonna assign to this, so it better be there */
721 return hv_fetch_common(hv, keysv, key, klen, flags,
722 HV_FETCH_ISSTORE, val, hash);
723 /* XXX Surely that could leak if the fetch-was-store fails?
724 Just like the hv_fetch. */
728 /* Welcome to hv_store... */
730 if (!xhv->xhv_array) {
731 /* Not sure if we can get here. I think the only case of oentry being
732 NULL is for %ENV with dynamic env fetch. But that should disappear
733 with magic in the previous code. */
734 Newz(503, xhv->xhv_array /* HvARRAY(hv) */,
735 PERL_HV_ARRAY_ALLOC_BYTES(xhv->xhv_max+1 /* HvMAX(hv)+1 */),
739 oentry = &((HE**)xhv->xhv_array)[hash & (I32) xhv->xhv_max];
742 /* share_hek_flags will do the free for us. This might be considered
745 HeKEY_hek(entry) = share_hek_flags(key, klen, hash, flags);
746 else /* gotta do the real thing */
747 HeKEY_hek(entry) = save_hek_flags(key, klen, hash, flags);
749 HeNEXT(entry) = *oentry;
752 if (val == &PL_sv_placeholder)
753 xhv->xhv_placeholders++;
754 if (masked_flags & HVhek_ENABLEHVKFLAGS)
757 xhv->xhv_keys++; /* HvKEYS(hv)++ */
758 if (!n_links) { /* initial entry? */
759 xhv->xhv_fill++; /* HvFILL(hv)++ */
760 } else if ((xhv->xhv_keys > (IV)xhv->xhv_max)
761 || ((n_links > HV_MAX_LENGTH_BEFORE_SPLIT) && !HvREHASH(hv))) {
762 /* Use only the old HvKEYS(hv) > HvMAX(hv) condition to limit bucket
763 splits on a rehashed hash, as we're not going to split it again,
764 and if someone is lucky (evil) enough to get all the keys in one
765 list they could exhaust our memory as we repeatedly double the
766 number of buckets on every entry. Linear search feels a less worse
775 S_hv_magic_check(pTHX_ HV *hv, bool *needs_copy, bool *needs_store)
777 MAGIC *mg = SvMAGIC(hv);
781 if (isUPPER(mg->mg_type)) {
783 switch (mg->mg_type) {
784 case PERL_MAGIC_tied:
786 *needs_store = FALSE;
789 mg = mg->mg_moremagic;
794 =for apidoc hv_scalar
796 Evaluates the hash in scalar context and returns the result. Handles magic when the hash is tied.
802 Perl_hv_scalar(pTHX_ HV *hv)
807 if ((SvRMAGICAL(hv) && (mg = mg_find((SV*)hv, PERL_MAGIC_tied)))) {
808 sv = magic_scalarpack(hv, mg);
814 Perl_sv_setpvf(aTHX_ sv, "%ld/%ld",
815 (long)HvFILL(hv), (long)HvMAX(hv) + 1);
823 =for apidoc hv_delete
825 Deletes a key/value pair in the hash. The value SV is removed from the
826 hash and returned to the caller. The C<klen> is the length of the key.
827 The C<flags> value will normally be zero; if set to G_DISCARD then NULL
834 Perl_hv_delete(pTHX_ HV *hv, const char *key, I32 klen_i32, I32 flags)
841 k_flags |= HVhek_UTF8;
845 return hv_delete_common(hv, NULL, key, klen, k_flags, flags, 0);
849 =for apidoc hv_delete_ent
851 Deletes a key/value pair in the hash. The value SV is removed from the
852 hash and returned to the caller. The C<flags> value will normally be zero;
853 if set to G_DISCARD then NULL will be returned. C<hash> can be a valid
854 precomputed hash value, or 0 to ask for it to be computed.
860 Perl_hv_delete_ent(pTHX_ HV *hv, SV *keysv, I32 flags, U32 hash)
862 return hv_delete_common(hv, keysv, NULL, 0, 0, flags, hash);
866 S_hv_delete_common(pTHX_ HV *hv, SV *keysv, const char *key, STRLEN klen,
867 int k_flags, I32 d_flags, U32 hash)
872 register HE **oentry;
881 if (k_flags & HVhek_FREEKEY)
883 key = SvPV(keysv, klen);
885 is_utf8 = (SvUTF8(keysv) != 0);
887 is_utf8 = ((k_flags & HVhek_UTF8) ? TRUE : FALSE);
890 if (SvRMAGICAL(hv)) {
893 hv_magic_check (hv, &needs_copy, &needs_store);
896 entry = hv_fetch_common(hv, keysv, key, klen,
897 k_flags & ~HVhek_FREEKEY, HV_FETCH_LVALUE,
899 sv = entry ? HeVAL(entry) : NULL;
905 if (mg_find(sv, PERL_MAGIC_tiedelem)) {
906 /* No longer an element */
907 sv_unmagic(sv, PERL_MAGIC_tiedelem);
910 return Nullsv; /* element cannot be deleted */
912 #ifdef ENV_IS_CASELESS
913 else if (mg_find((SV*)hv, PERL_MAGIC_env)) {
914 /* XXX This code isn't UTF8 clean. */
915 keysv = sv_2mortal(newSVpvn(key,klen));
916 if (k_flags & HVhek_FREEKEY) {
919 key = strupr(SvPVX(keysv));
928 xhv = (XPVHV*)SvANY(hv);
929 if (!xhv->xhv_array /* !HvARRAY(hv) */)
933 const char *keysave = key;
934 key = (char*)bytes_from_utf8((U8*)key, &klen, &is_utf8);
937 k_flags |= HVhek_UTF8;
939 k_flags &= ~HVhek_UTF8;
940 if (key != keysave) {
941 if (k_flags & HVhek_FREEKEY) {
942 /* This shouldn't happen if our caller does what we expect,
943 but strictly the API allows it. */
946 k_flags |= HVhek_WASUTF8 | HVhek_FREEKEY;
948 HvHASKFLAGS_on((SV*)hv);
952 PERL_HASH_INTERNAL(hash, key, klen);
954 if (keysv && (SvIsCOW_shared_hash(keysv))) {
957 PERL_HASH(hash, key, klen);
959 PERL_HASH(hash, key, klen);
962 masked_flags = (k_flags & HVhek_MASK);
964 /* oentry = &(HvARRAY(hv))[hash & (I32) HvMAX(hv)]; */
965 oentry = &((HE**)xhv->xhv_array)[hash & (I32) xhv->xhv_max];
968 for (; entry; i=0, oentry = &HeNEXT(entry), entry = *oentry) {
969 if (HeHASH(entry) != hash) /* strings can't be equal */
971 if (HeKLEN(entry) != (I32)klen)
973 if (HeKEY(entry) != key && memNE(HeKEY(entry),key,klen)) /* is this it? */
975 if ((HeKFLAGS(entry) ^ masked_flags) & HVhek_UTF8)
977 if (k_flags & HVhek_FREEKEY)
980 /* if placeholder is here, it's already been deleted.... */
981 if (HeVAL(entry) == &PL_sv_placeholder)
984 return Nullsv; /* if still SvREADONLY, leave it deleted. */
986 /* okay, really delete the placeholder. */
987 *oentry = HeNEXT(entry);
989 xhv->xhv_fill--; /* HvFILL(hv)-- */
990 if (entry == xhv->xhv_eiter /* HvEITER(hv) */)
993 hv_free_ent(hv, entry);
994 xhv->xhv_keys--; /* HvKEYS(hv)-- */
995 if (xhv->xhv_keys == 0)
997 xhv->xhv_placeholders--;
1000 else if (SvREADONLY(hv) && HeVAL(entry) && SvREADONLY(HeVAL(entry))) {
1001 S_hv_notallowed(aTHX_ k_flags, key, klen,
1002 "delete readonly key '%"SVf"' from"
1006 if (d_flags & G_DISCARD)
1009 sv = sv_2mortal(HeVAL(entry));
1010 HeVAL(entry) = &PL_sv_placeholder;
1014 * If a restricted hash, rather than really deleting the entry, put
1015 * a placeholder there. This marks the key as being "approved", so
1016 * we can still access via not-really-existing key without raising
1019 if (SvREADONLY(hv)) {
1020 HeVAL(entry) = &PL_sv_placeholder;
1021 /* We'll be saving this slot, so the number of allocated keys
1022 * doesn't go down, but the number placeholders goes up */
1023 xhv->xhv_placeholders++; /* HvPLACEHOLDERS(hv)++ */
1025 *oentry = HeNEXT(entry);
1027 xhv->xhv_fill--; /* HvFILL(hv)-- */
1028 if (entry == xhv->xhv_eiter /* HvEITER(hv) */)
1031 hv_free_ent(hv, entry);
1032 xhv->xhv_keys--; /* HvKEYS(hv)-- */
1033 if (xhv->xhv_keys == 0)
1034 HvHASKFLAGS_off(hv);
1038 if (SvREADONLY(hv)) {
1039 S_hv_notallowed(aTHX_ k_flags, key, klen,
1040 "delete disallowed key '%"SVf"' from"
1044 if (k_flags & HVhek_FREEKEY)
1050 S_hsplit(pTHX_ HV *hv)
1052 register XPVHV* xhv = (XPVHV*)SvANY(hv);
1053 I32 oldsize = (I32) xhv->xhv_max+1; /* HvMAX(hv)+1 (sick) */
1054 register I32 newsize = oldsize * 2;
1056 register char *a = xhv->xhv_array; /* HvARRAY(hv) */
1060 register HE **oentry;
1061 int longest_chain = 0;
1065 #if defined(STRANGE_MALLOC) || defined(MYMALLOC)
1066 Renew(a, PERL_HV_ARRAY_ALLOC_BYTES(newsize), char);
1072 New(2, a, PERL_HV_ARRAY_ALLOC_BYTES(newsize), char);
1077 Copy(xhv->xhv_array /* HvARRAY(hv) */, a, oldsize * sizeof(HE*), char);
1078 if (oldsize >= 64) {
1079 offer_nice_chunk(xhv->xhv_array /* HvARRAY(hv) */,
1080 PERL_HV_ARRAY_ALLOC_BYTES(oldsize));
1083 Safefree(xhv->xhv_array /* HvARRAY(hv) */);
1087 Zero(&a[oldsize * sizeof(HE*)], (newsize-oldsize) * sizeof(HE*), char); /* zero 2nd half*/
1088 xhv->xhv_max = --newsize; /* HvMAX(hv) = --newsize */
1089 xhv->xhv_array = a; /* HvARRAY(hv) = a */
1092 for (i=0; i<oldsize; i++,aep++) {
1093 int left_length = 0;
1094 int right_length = 0;
1096 if (!*aep) /* non-existent */
1099 for (oentry = aep, entry = *aep; entry; entry = *oentry) {
1100 if ((HeHASH(entry) & newsize) != (U32)i) {
1101 *oentry = HeNEXT(entry);
1102 HeNEXT(entry) = *bep;
1104 xhv->xhv_fill++; /* HvFILL(hv)++ */
1110 oentry = &HeNEXT(entry);
1114 if (!*aep) /* everything moved */
1115 xhv->xhv_fill--; /* HvFILL(hv)-- */
1116 /* I think we don't actually need to keep track of the longest length,
1117 merely flag if anything is too long. But for the moment while
1118 developing this code I'll track it. */
1119 if (left_length > longest_chain)
1120 longest_chain = left_length;
1121 if (right_length > longest_chain)
1122 longest_chain = right_length;
1126 /* Pick your policy for "hashing isn't working" here: */
1127 if (longest_chain <= HV_MAX_LENGTH_BEFORE_SPLIT /* split worked? */
1132 if (hv == PL_strtab) {
1133 /* Urg. Someone is doing something nasty to the string table.
1138 /* Awooga. Awooga. Pathological data. */
1139 /*PerlIO_printf(PerlIO_stderr(), "%p %d of %d with %d/%d buckets\n", hv,
1140 longest_chain, HvTOTALKEYS(hv), HvFILL(hv), 1+HvMAX(hv));*/
1143 Newz(2, a, PERL_HV_ARRAY_ALLOC_BYTES(newsize), char);
1144 was_shared = HvSHAREKEYS(hv);
1147 HvSHAREKEYS_off(hv);
1150 aep = (HE **) xhv->xhv_array;
1152 for (i=0; i<newsize; i++,aep++) {
1155 /* We're going to trash this HE's next pointer when we chain it
1156 into the new hash below, so store where we go next. */
1157 HE *next = HeNEXT(entry);
1161 PERL_HASH_INTERNAL(hash, HeKEY(entry), HeKLEN(entry));
1166 = save_hek_flags(HeKEY(entry), HeKLEN(entry),
1167 hash, HeKFLAGS(entry));
1168 unshare_hek (HeKEY_hek(entry));
1169 HeKEY_hek(entry) = new_hek;
1171 /* Not shared, so simply write the new hash in. */
1172 HeHASH(entry) = hash;
1174 /*PerlIO_printf(PerlIO_stderr(), "%d ", HeKFLAGS(entry));*/
1175 HEK_REHASH_on(HeKEY_hek(entry));
1176 /*PerlIO_printf(PerlIO_stderr(), "%d\n", HeKFLAGS(entry));*/
1178 /* Copy oentry to the correct new chain. */
1179 bep = ((HE**)a) + (hash & (I32) xhv->xhv_max);
1181 xhv->xhv_fill++; /* HvFILL(hv)++ */
1182 HeNEXT(entry) = *bep;
1188 Safefree (xhv->xhv_array);
1189 xhv->xhv_array = a; /* HvARRAY(hv) = a */
1193 Perl_hv_ksplit(pTHX_ HV *hv, IV newmax)
1195 register XPVHV* xhv = (XPVHV*)SvANY(hv);
1196 I32 oldsize = (I32) xhv->xhv_max+1; /* HvMAX(hv)+1 (sick) */
1197 register I32 newsize;
1203 register HE **oentry;
1205 newsize = (I32) newmax; /* possible truncation here */
1206 if (newsize != newmax || newmax <= oldsize)
1208 while ((newsize & (1 + ~newsize)) != newsize) {
1209 newsize &= ~(newsize & (1 + ~newsize)); /* get proper power of 2 */
1211 if (newsize < newmax)
1213 if (newsize < newmax)
1214 return; /* overflow detection */
1216 a = xhv->xhv_array; /* HvARRAY(hv) */
1219 #if defined(STRANGE_MALLOC) || defined(MYMALLOC)
1220 Renew(a, PERL_HV_ARRAY_ALLOC_BYTES(newsize), char);
1226 New(2, a, PERL_HV_ARRAY_ALLOC_BYTES(newsize), char);
1231 Copy(xhv->xhv_array /* HvARRAY(hv) */, a, oldsize * sizeof(HE*), char);
1232 if (oldsize >= 64) {
1233 offer_nice_chunk(xhv->xhv_array /* HvARRAY(hv) */,
1234 PERL_HV_ARRAY_ALLOC_BYTES(oldsize));
1237 Safefree(xhv->xhv_array /* HvARRAY(hv) */);
1240 Zero(&a[oldsize * sizeof(HE*)], (newsize-oldsize) * sizeof(HE*), char); /* zero 2nd half*/
1243 Newz(0, a, PERL_HV_ARRAY_ALLOC_BYTES(newsize), char);
1245 xhv->xhv_max = --newsize; /* HvMAX(hv) = --newsize */
1246 xhv->xhv_array = a; /* HvARRAY(hv) = a */
1247 if (!xhv->xhv_fill /* !HvFILL(hv) */) /* skip rest if no entries */
1251 for (i=0; i<oldsize; i++,aep++) {
1252 if (!*aep) /* non-existent */
1254 for (oentry = aep, entry = *aep; entry; entry = *oentry) {
1255 if ((j = (HeHASH(entry) & newsize)) != i) {
1257 *oentry = HeNEXT(entry);
1258 if (!(HeNEXT(entry) = aep[j]))
1259 xhv->xhv_fill++; /* HvFILL(hv)++ */
1264 oentry = &HeNEXT(entry);
1266 if (!*aep) /* everything moved */
1267 xhv->xhv_fill--; /* HvFILL(hv)-- */
1274 Creates a new HV. The reference count is set to 1.
1283 register XPVHV* xhv;
1285 hv = (HV*)NEWSV(502,0);
1286 sv_upgrade((SV *)hv, SVt_PVHV);
1287 xhv = (XPVHV*)SvANY(hv);
1290 #ifndef NODEFAULT_SHAREKEYS
1291 HvSHAREKEYS_on(hv); /* key-sharing on by default */
1294 xhv->xhv_max = 7; /* HvMAX(hv) = 7 (start with 8 buckets) */
1295 xhv->xhv_fill = 0; /* HvFILL(hv) = 0 */
1296 xhv->xhv_pmroot = 0; /* HvPMROOT(hv) = 0 */
1297 (void)hv_iterinit(hv); /* so each() will start off right */
1302 Perl_newHVhv(pTHX_ HV *ohv)
1305 STRLEN hv_max, hv_fill;
1307 if (!ohv || (hv_fill = HvFILL(ohv)) == 0)
1309 hv_max = HvMAX(ohv);
1311 if (!SvMAGICAL((SV *)ohv)) {
1312 /* It's an ordinary hash, so copy it fast. AMS 20010804 */
1314 bool shared = !!HvSHAREKEYS(ohv);
1315 HE **ents, **oents = (HE **)HvARRAY(ohv);
1317 New(0, a, PERL_HV_ARRAY_ALLOC_BYTES(hv_max+1), char);
1320 /* In each bucket... */
1321 for (i = 0; i <= hv_max; i++) {
1322 HE *prev = NULL, *ent = NULL, *oent = oents[i];
1329 /* Copy the linked list of entries. */
1330 for (oent = oents[i]; oent; oent = HeNEXT(oent)) {
1331 U32 hash = HeHASH(oent);
1332 char *key = HeKEY(oent);
1333 STRLEN len = HeKLEN(oent);
1334 int flags = HeKFLAGS(oent);
1337 HeVAL(ent) = newSVsv(HeVAL(oent));
1339 = shared ? share_hek_flags(key, len, hash, flags)
1340 : save_hek_flags(key, len, hash, flags);
1351 HvFILL(hv) = hv_fill;
1352 HvTOTALKEYS(hv) = HvTOTALKEYS(ohv);
1356 /* Iterate over ohv, copying keys and values one at a time. */
1358 I32 riter = HvRITER(ohv);
1359 HE *eiter = HvEITER(ohv);
1361 /* Can we use fewer buckets? (hv_max is always 2^n-1) */
1362 while (hv_max && hv_max + 1 >= hv_fill * 2)
1363 hv_max = hv_max / 2;
1367 while ((entry = hv_iternext_flags(ohv, 0))) {
1368 hv_store_flags(hv, HeKEY(entry), HeKLEN(entry),
1369 newSVsv(HeVAL(entry)), HeHASH(entry),
1372 HvRITER(ohv) = riter;
1373 HvEITER(ohv) = eiter;
1380 Perl_hv_free_ent(pTHX_ HV *hv, register HE *entry)
1387 if (val && isGV(val) && GvCVu(val) && HvNAME(hv))
1388 PL_sub_generation++; /* may be deletion of method from stash */
1390 if (HeKLEN(entry) == HEf_SVKEY) {
1391 SvREFCNT_dec(HeKEY_sv(entry));
1392 Safefree(HeKEY_hek(entry));
1394 else if (HvSHAREKEYS(hv))
1395 unshare_hek(HeKEY_hek(entry));
1397 Safefree(HeKEY_hek(entry));
1402 Perl_hv_delayfree_ent(pTHX_ HV *hv, register HE *entry)
1406 if (isGV(HeVAL(entry)) && GvCVu(HeVAL(entry)) && HvNAME(hv))
1407 PL_sub_generation++; /* may be deletion of method from stash */
1408 sv_2mortal(HeVAL(entry)); /* free between statements */
1409 if (HeKLEN(entry) == HEf_SVKEY) {
1410 sv_2mortal(HeKEY_sv(entry));
1411 Safefree(HeKEY_hek(entry));
1413 else if (HvSHAREKEYS(hv))
1414 unshare_hek(HeKEY_hek(entry));
1416 Safefree(HeKEY_hek(entry));
1421 =for apidoc hv_clear
1423 Clears a hash, making it empty.
1429 Perl_hv_clear(pTHX_ HV *hv)
1431 register XPVHV* xhv;
1435 DEBUG_A(Perl_hv_assert(aTHX_ hv));
1437 xhv = (XPVHV*)SvANY(hv);
1439 if (SvREADONLY(hv) && xhv->xhv_array != NULL) {
1440 /* restricted hash: convert all keys to placeholders */
1443 for (i = 0; i <= (I32) xhv->xhv_max; i++) {
1444 entry = ((HE**)xhv->xhv_array)[i];
1445 for (; entry; entry = HeNEXT(entry)) {
1446 /* not already placeholder */
1447 if (HeVAL(entry) != &PL_sv_placeholder) {
1448 if (HeVAL(entry) && SvREADONLY(HeVAL(entry))) {
1449 SV* keysv = hv_iterkeysv(entry);
1451 "Attempt to delete readonly key '%"SVf"' from a restricted hash",
1454 SvREFCNT_dec(HeVAL(entry));
1455 HeVAL(entry) = &PL_sv_placeholder;
1456 xhv->xhv_placeholders++; /* HvPLACEHOLDERS(hv)++ */
1464 xhv->xhv_placeholders = 0; /* HvPLACEHOLDERS(hv) = 0 */
1465 if (xhv->xhv_array /* HvARRAY(hv) */)
1466 (void)memzero(xhv->xhv_array /* HvARRAY(hv) */,
1467 (xhv->xhv_max+1 /* HvMAX(hv)+1 */) * sizeof(HE*));
1472 HvHASKFLAGS_off(hv);
1479 =for apidoc hv_clear_placeholders
1481 Clears any placeholders from a hash. If a restricted hash has any of its keys
1482 marked as readonly and the key is subsequently deleted, the key is not actually
1483 deleted but is marked by assigning it a value of &PL_sv_placeholder. This tags
1484 it so it will be ignored by future operations such as iterating over the hash,
1485 but will still allow the hash to have a value reaasigned to the key at some
1486 future point. This function clears any such placeholder keys from the hash.
1487 See Hash::Util::lock_keys() for an example of its use.
1493 Perl_hv_clear_placeholders(pTHX_ HV *hv)
1496 items = (I32)HvPLACEHOLDERS(hv);
1499 I32 riter = HvRITER(hv);
1500 HE *eiter = HvEITER(hv);
1502 /* This may look suboptimal with the items *after* the iternext, but
1503 it's quite deliberate. We only get here with items==0 if we've
1504 just deleted the last placeholder in the hash. If we've just done
1505 that then it means that the hash is in lazy delete mode, and the
1506 HE is now only referenced in our iterator. If we just quit the loop
1507 and discarded our iterator then the HE leaks. So we do the && the
1508 other way to ensure iternext is called just one more time, which
1509 has the side effect of triggering the lazy delete. */
1510 while ((entry = hv_iternext_flags(hv, HV_ITERNEXT_WANTPLACEHOLDERS))
1512 SV *val = hv_iterval(hv, entry);
1514 if (val == &PL_sv_placeholder) {
1516 /* It seems that I have to go back in the front of the hash
1517 API to delete a hash, even though I have a HE structure
1518 pointing to the very entry I want to delete, and could hold
1519 onto the previous HE that points to it. And it's easier to
1520 go in with SVs as I can then specify the precomputed hash,
1521 and don't have fun and games with utf8 keys. */
1522 SV *key = hv_iterkeysv(entry);
1524 hv_delete_ent (hv, key, G_DISCARD, HeHASH(entry));
1528 HvRITER(hv) = riter;
1529 HvEITER(hv) = eiter;
1534 S_hfreeentries(pTHX_ HV *hv)
1536 register HE **array;
1538 register HE *oentry = Null(HE*);
1549 array = HvARRAY(hv);
1550 /* make everyone else think the array is empty, so that the destructors
1551 * called for freed entries can't recusively mess with us */
1552 HvARRAY(hv) = Null(HE**);
1554 ((XPVHV*) SvANY(hv))->xhv_keys = 0;
1560 entry = HeNEXT(entry);
1561 hv_free_ent(hv, oentry);
1566 entry = array[riter];
1569 HvARRAY(hv) = array;
1570 (void)hv_iterinit(hv);
1574 =for apidoc hv_undef
1582 Perl_hv_undef(pTHX_ HV *hv)
1584 register XPVHV* xhv;
1587 DEBUG_A(Perl_hv_assert(aTHX_ hv));
1588 xhv = (XPVHV*)SvANY(hv);
1590 Safefree(xhv->xhv_array /* HvARRAY(hv) */);
1593 hv_delete(PL_stashcache, HvNAME(hv), strlen(HvNAME(hv)), G_DISCARD);
1594 Safefree(HvNAME(hv));
1597 xhv->xhv_max = 7; /* HvMAX(hv) = 7 (it's a normal hash) */
1598 xhv->xhv_array = 0; /* HvARRAY(hv) = 0 */
1599 xhv->xhv_placeholders = 0; /* HvPLACEHOLDERS(hv) = 0 */
1606 =for apidoc hv_iterinit
1608 Prepares a starting point to traverse a hash table. Returns the number of
1609 keys in the hash (i.e. the same as C<HvKEYS(tb)>). The return value is
1610 currently only meaningful for hashes without tie magic.
1612 NOTE: Before version 5.004_65, C<hv_iterinit> used to return the number of
1613 hash buckets that happen to be in use. If you still need that esoteric
1614 value, you can get it through the macro C<HvFILL(tb)>.
1621 Perl_hv_iterinit(pTHX_ HV *hv)
1623 register XPVHV* xhv;
1627 Perl_croak(aTHX_ "Bad hash");
1628 xhv = (XPVHV*)SvANY(hv);
1629 entry = xhv->xhv_eiter; /* HvEITER(hv) */
1630 if (entry && HvLAZYDEL(hv)) { /* was deleted earlier? */
1632 hv_free_ent(hv, entry);
1634 xhv->xhv_riter = -1; /* HvRITER(hv) = -1 */
1635 xhv->xhv_eiter = Null(HE*); /* HvEITER(hv) = Null(HE*) */
1636 /* used to be xhv->xhv_fill before 5.004_65 */
1637 return XHvTOTALKEYS(xhv);
1640 =for apidoc hv_iternext
1642 Returns entries from a hash iterator. See C<hv_iterinit>.
1644 You may call C<hv_delete> or C<hv_delete_ent> on the hash entry that the
1645 iterator currently points to, without losing your place or invalidating your
1646 iterator. Note that in this case the current entry is deleted from the hash
1647 with your iterator holding the last reference to it. Your iterator is flagged
1648 to free the entry on the next call to C<hv_iternext>, so you must not discard
1649 your iterator immediately else the entry will leak - call C<hv_iternext> to
1650 trigger the resource deallocation.
1656 Perl_hv_iternext(pTHX_ HV *hv)
1658 return hv_iternext_flags(hv, 0);
1662 =for apidoc hv_iternext_flags
1664 Returns entries from a hash iterator. See C<hv_iterinit> and C<hv_iternext>.
1665 The C<flags> value will normally be zero; if HV_ITERNEXT_WANTPLACEHOLDERS is
1666 set the placeholders keys (for restricted hashes) will be returned in addition
1667 to normal keys. By default placeholders are automatically skipped over.
1668 Currently a placeholder is implemented with a value that is
1669 C<&Perl_sv_placeholder>. Note that the implementation of placeholders and
1670 restricted hashes may change, and the implementation currently is
1671 insufficiently abstracted for any change to be tidy.
1677 Perl_hv_iternext_flags(pTHX_ HV *hv, I32 flags)
1679 register XPVHV* xhv;
1685 Perl_croak(aTHX_ "Bad hash");
1686 xhv = (XPVHV*)SvANY(hv);
1687 oldentry = entry = xhv->xhv_eiter; /* HvEITER(hv) */
1689 if ((mg = SvTIED_mg((SV*)hv, PERL_MAGIC_tied))) {
1690 SV *key = sv_newmortal();
1692 sv_setsv(key, HeSVKEY_force(entry));
1693 SvREFCNT_dec(HeSVKEY(entry)); /* get rid of previous key */
1699 /* one HE per MAGICAL hash */
1700 xhv->xhv_eiter = entry = new_HE(); /* HvEITER(hv) = new_HE() */
1702 Newz(54, k, HEK_BASESIZE + sizeof(SV*), char);
1704 HeKEY_hek(entry) = hek;
1705 HeKLEN(entry) = HEf_SVKEY;
1707 magic_nextpack((SV*) hv,mg,key);
1709 /* force key to stay around until next time */
1710 HeSVKEY_set(entry, SvREFCNT_inc(key));
1711 return entry; /* beware, hent_val is not set */
1714 SvREFCNT_dec(HeVAL(entry));
1715 Safefree(HeKEY_hek(entry));
1717 xhv->xhv_eiter = Null(HE*); /* HvEITER(hv) = Null(HE*) */
1720 #ifdef DYNAMIC_ENV_FETCH /* set up %ENV for iteration */
1721 if (!entry && SvRMAGICAL((SV*)hv) && mg_find((SV*)hv, PERL_MAGIC_env))
1725 if (!xhv->xhv_array /* !HvARRAY(hv) */)
1726 Newz(506, xhv->xhv_array /* HvARRAY(hv) */,
1727 PERL_HV_ARRAY_ALLOC_BYTES(xhv->xhv_max+1 /* HvMAX(hv)+1 */),
1729 /* At start of hash, entry is NULL. */
1732 entry = HeNEXT(entry);
1733 if (!(flags & HV_ITERNEXT_WANTPLACEHOLDERS)) {
1735 * Skip past any placeholders -- don't want to include them in
1738 while (entry && HeVAL(entry) == &PL_sv_placeholder) {
1739 entry = HeNEXT(entry);
1744 /* OK. Come to the end of the current list. Grab the next one. */
1746 xhv->xhv_riter++; /* HvRITER(hv)++ */
1747 if (xhv->xhv_riter > (I32)xhv->xhv_max /* HvRITER(hv) > HvMAX(hv) */) {
1748 /* There is no next one. End of the hash. */
1749 xhv->xhv_riter = -1; /* HvRITER(hv) = -1 */
1752 /* entry = (HvARRAY(hv))[HvRITER(hv)]; */
1753 entry = ((HE**)xhv->xhv_array)[xhv->xhv_riter];
1755 if (!(flags & HV_ITERNEXT_WANTPLACEHOLDERS)) {
1756 /* If we have an entry, but it's a placeholder, don't count it.
1758 while (entry && HeVAL(entry) == &PL_sv_placeholder)
1759 entry = HeNEXT(entry);
1761 /* Will loop again if this linked list starts NULL
1762 (for HV_ITERNEXT_WANTPLACEHOLDERS)
1763 or if we run through it and find only placeholders. */
1766 if (oldentry && HvLAZYDEL(hv)) { /* was deleted earlier? */
1768 hv_free_ent(hv, oldentry);
1771 /*if (HvREHASH(hv) && entry && !HeKREHASH(entry))
1772 PerlIO_printf(PerlIO_stderr(), "Awooga %p %p\n", hv, entry);*/
1774 xhv->xhv_eiter = entry; /* HvEITER(hv) = entry */
1779 =for apidoc hv_iterkey
1781 Returns the key from the current position of the hash iterator. See
1788 Perl_hv_iterkey(pTHX_ register HE *entry, I32 *retlen)
1790 if (HeKLEN(entry) == HEf_SVKEY) {
1792 char *p = SvPV(HeKEY_sv(entry), len);
1797 *retlen = HeKLEN(entry);
1798 return HeKEY(entry);
1802 /* unlike hv_iterval(), this always returns a mortal copy of the key */
1804 =for apidoc hv_iterkeysv
1806 Returns the key as an C<SV*> from the current position of the hash
1807 iterator. The return value will always be a mortal copy of the key. Also
1814 Perl_hv_iterkeysv(pTHX_ register HE *entry)
1816 if (HeKLEN(entry) != HEf_SVKEY) {
1817 HEK *hek = HeKEY_hek(entry);
1818 int flags = HEK_FLAGS(hek);
1821 if (flags & HVhek_WASUTF8) {
1823 Andreas would like keys he put in as utf8 to come back as utf8
1825 STRLEN utf8_len = HEK_LEN(hek);
1826 U8 *as_utf8 = bytes_to_utf8 ((U8*)HEK_KEY(hek), &utf8_len);
1828 sv = newSVpvn ((char*)as_utf8, utf8_len);
1830 Safefree (as_utf8); /* bytes_to_utf8() allocates a new string */
1831 } else if (flags & HVhek_REHASH) {
1832 /* We don't have a pointer to the hv, so we have to replicate the
1833 flag into every HEK. This hv is using custom a hasing
1834 algorithm. Hence we can't return a shared string scalar, as
1835 that would contain the (wrong) hash value, and might get passed
1836 into an hv routine with a regular hash */
1838 sv = newSVpvn (HEK_KEY(hek), HEK_LEN(hek));
1842 sv = newSVpvn_share(HEK_KEY(hek),
1843 (HEK_UTF8(hek) ? -HEK_LEN(hek) : HEK_LEN(hek)),
1846 return sv_2mortal(sv);
1848 return sv_mortalcopy(HeKEY_sv(entry));
1852 =for apidoc hv_iterval
1854 Returns the value from the current position of the hash iterator. See
1861 Perl_hv_iterval(pTHX_ HV *hv, register HE *entry)
1863 if (SvRMAGICAL(hv)) {
1864 if (mg_find((SV*)hv, PERL_MAGIC_tied)) {
1865 SV* sv = sv_newmortal();
1866 if (HeKLEN(entry) == HEf_SVKEY)
1867 mg_copy((SV*)hv, sv, (char*)HeKEY_sv(entry), HEf_SVKEY);
1868 else mg_copy((SV*)hv, sv, HeKEY(entry), HeKLEN(entry));
1872 return HeVAL(entry);
1876 =for apidoc hv_iternextsv
1878 Performs an C<hv_iternext>, C<hv_iterkey>, and C<hv_iterval> in one
1885 Perl_hv_iternextsv(pTHX_ HV *hv, char **key, I32 *retlen)
1888 if ( (he = hv_iternext_flags(hv, 0)) == NULL)
1890 *key = hv_iterkey(he, retlen);
1891 return hv_iterval(hv, he);
1895 =for apidoc hv_magic
1897 Adds magic to a hash. See C<sv_magic>.
1903 Perl_hv_magic(pTHX_ HV *hv, GV *gv, int how)
1905 sv_magic((SV*)hv, (SV*)gv, how, Nullch, 0);
1908 #if 0 /* use the macro from hv.h instead */
1911 Perl_sharepvn(pTHX_ const char *sv, I32 len, U32 hash)
1913 return HEK_KEY(share_hek(sv, len, hash));
1918 /* possibly free a shared string if no one has access to it
1919 * len and hash must both be valid for str.
1922 Perl_unsharepvn(pTHX_ const char *str, I32 len, U32 hash)
1924 unshare_hek_or_pvn (NULL, str, len, hash);
1929 Perl_unshare_hek(pTHX_ HEK *hek)
1931 unshare_hek_or_pvn(hek, NULL, 0, 0);
1934 /* possibly free a shared string if no one has access to it
1935 hek if non-NULL takes priority over the other 3, else str, len and hash
1936 are used. If so, len and hash must both be valid for str.
1939 S_unshare_hek_or_pvn(pTHX_ HEK *hek, const char *str, I32 len, U32 hash)
1941 register XPVHV* xhv;
1943 register HE **oentry;
1946 bool is_utf8 = FALSE;
1948 const char *save = str;
1951 hash = HEK_HASH(hek);
1952 } else if (len < 0) {
1953 STRLEN tmplen = -len;
1955 /* See the note in hv_fetch(). --jhi */
1956 str = (char*)bytes_from_utf8((U8*)str, &tmplen, &is_utf8);
1959 k_flags = HVhek_UTF8;
1961 k_flags |= HVhek_WASUTF8 | HVhek_FREEKEY;
1964 /* what follows is the moral equivalent of:
1965 if ((Svp = hv_fetch(PL_strtab, tmpsv, FALSE, hash))) {
1966 if (--*Svp == Nullsv)
1967 hv_delete(PL_strtab, str, len, G_DISCARD, hash);
1969 xhv = (XPVHV*)SvANY(PL_strtab);
1970 /* assert(xhv_array != 0) */
1972 /* oentry = &(HvARRAY(hv))[hash & (I32) HvMAX(hv)]; */
1973 oentry = &((HE**)xhv->xhv_array)[hash & (I32) xhv->xhv_max];
1975 for (entry = *oentry; entry; i=0, oentry = &HeNEXT(entry), entry = *oentry) {
1976 if (HeKEY_hek(entry) != hek)
1982 int flags_masked = k_flags & HVhek_MASK;
1983 for (entry = *oentry; entry; i=0, oentry = &HeNEXT(entry), entry = *oentry) {
1984 if (HeHASH(entry) != hash) /* strings can't be equal */
1986 if (HeKLEN(entry) != len)
1988 if (HeKEY(entry) != str && memNE(HeKEY(entry),str,len)) /* is this it? */
1990 if (HeKFLAGS(entry) != flags_masked)
1998 if (--HeVAL(entry) == Nullsv) {
1999 *oentry = HeNEXT(entry);
2001 xhv->xhv_fill--; /* HvFILL(hv)-- */
2002 Safefree(HeKEY_hek(entry));
2004 xhv->xhv_keys--; /* HvKEYS(hv)-- */
2008 UNLOCK_STRTAB_MUTEX;
2009 if (!found && ckWARN_d(WARN_INTERNAL))
2010 Perl_warner(aTHX_ packWARN(WARN_INTERNAL),
2011 "Attempt to free non-existent shared string '%s'%s",
2012 hek ? HEK_KEY(hek) : str,
2013 (k_flags & HVhek_UTF8) ? " (utf8)" : "");
2014 if (k_flags & HVhek_FREEKEY)
2018 /* get a (constant) string ptr from the global string table
2019 * string will get added if it is not already there.
2020 * len and hash must both be valid for str.
2023 Perl_share_hek(pTHX_ const char *str, I32 len, register U32 hash)
2025 bool is_utf8 = FALSE;
2027 const char *save = str;
2030 STRLEN tmplen = -len;
2032 /* See the note in hv_fetch(). --jhi */
2033 str = (char*)bytes_from_utf8((U8*)str, &tmplen, &is_utf8);
2035 /* If we were able to downgrade here, then than means that we were passed
2036 in a key which only had chars 0-255, but was utf8 encoded. */
2039 /* If we found we were able to downgrade the string to bytes, then
2040 we should flag that it needs upgrading on keys or each. Also flag
2041 that we need share_hek_flags to free the string. */
2043 flags |= HVhek_WASUTF8 | HVhek_FREEKEY;
2046 return share_hek_flags (str, len, hash, flags);
2050 S_share_hek_flags(pTHX_ const char *str, I32 len, register U32 hash, int flags)
2052 register XPVHV* xhv;
2054 register HE **oentry;
2057 int flags_masked = flags & HVhek_MASK;
2059 /* what follows is the moral equivalent of:
2061 if (!(Svp = hv_fetch(PL_strtab, str, len, FALSE)))
2062 hv_store(PL_strtab, str, len, Nullsv, hash);
2064 Can't rehash the shared string table, so not sure if it's worth
2065 counting the number of entries in the linked list
2067 xhv = (XPVHV*)SvANY(PL_strtab);
2068 /* assert(xhv_array != 0) */
2070 /* oentry = &(HvARRAY(hv))[hash & (I32) HvMAX(hv)]; */
2071 oentry = &((HE**)xhv->xhv_array)[hash & (I32) xhv->xhv_max];
2072 for (entry = *oentry; entry; i=0, entry = HeNEXT(entry)) {
2073 if (HeHASH(entry) != hash) /* strings can't be equal */
2075 if (HeKLEN(entry) != len)
2077 if (HeKEY(entry) != str && memNE(HeKEY(entry),str,len)) /* is this it? */
2079 if (HeKFLAGS(entry) != flags_masked)
2086 HeKEY_hek(entry) = save_hek_flags(str, len, hash, flags);
2087 HeVAL(entry) = Nullsv;
2088 HeNEXT(entry) = *oentry;
2090 xhv->xhv_keys++; /* HvKEYS(hv)++ */
2091 if (i) { /* initial entry? */
2092 xhv->xhv_fill++; /* HvFILL(hv)++ */
2093 } else if (xhv->xhv_keys > (IV)xhv->xhv_max /* HvKEYS(hv) > HvMAX(hv) */) {
2098 ++HeVAL(entry); /* use value slot as REFCNT */
2099 UNLOCK_STRTAB_MUTEX;
2101 if (flags & HVhek_FREEKEY)
2104 return HeKEY_hek(entry);
2109 =for apidoc hv_assert
2111 Check that a hash is in an internally consistent state.
2117 Perl_hv_assert(pTHX_ HV *hv)
2121 int placeholders = 0;
2124 I32 riter = HvRITER(hv);
2125 HE *eiter = HvEITER(hv);
2127 (void)hv_iterinit(hv);
2129 while ((entry = hv_iternext_flags(hv, HV_ITERNEXT_WANTPLACEHOLDERS))) {
2130 /* sanity check the values */
2131 if (HeVAL(entry) == &PL_sv_placeholder) {
2136 /* sanity check the keys */
2137 if (HeSVKEY(entry)) {
2138 /* Don't know what to check on SV keys. */
2139 } else if (HeKUTF8(entry)) {
2141 if (HeKWASUTF8(entry)) {
2142 PerlIO_printf(Perl_debug_log,
2143 "hash key has both WASUFT8 and UTF8: '%.*s'\n",
2144 (int) HeKLEN(entry), HeKEY(entry));
2147 } else if (HeKWASUTF8(entry)) {
2151 if (!SvTIED_mg((SV*)hv, PERL_MAGIC_tied)) {
2152 if (HvUSEDKEYS(hv) != real) {
2153 PerlIO_printf(Perl_debug_log, "Count %d key(s), but hash reports %d\n",
2154 (int) real, (int) HvUSEDKEYS(hv));
2157 if (HvPLACEHOLDERS(hv) != placeholders) {
2158 PerlIO_printf(Perl_debug_log,
2159 "Count %d placeholder(s), but hash reports %d\n",
2160 (int) placeholders, (int) HvPLACEHOLDERS(hv));
2164 if (withflags && ! HvHASKFLAGS(hv)) {
2165 PerlIO_printf(Perl_debug_log,
2166 "Hash has HASKFLAGS off but I count %d key(s) with flags\n",
2173 HvRITER(hv) = riter; /* Restore hash iterator state */
2174 HvEITER(hv) = eiter;