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)
987 return Nullsv; /* if still SvREADONLY, leave it deleted. */
989 /* okay, really delete the placeholder. */
990 *oentry = HeNEXT(entry);
992 xhv->xhv_fill--; /* HvFILL(hv)-- */
993 if (entry == xhv->xhv_eiter /* HvEITER(hv) */)
996 hv_free_ent(hv, entry);
997 xhv->xhv_keys--; /* HvKEYS(hv)-- */
998 if (xhv->xhv_keys == 0)
1000 xhv->xhv_placeholders--;
1003 else if (SvREADONLY(hv) && HeVAL(entry) && SvREADONLY(HeVAL(entry))) {
1004 S_hv_notallowed(aTHX_ k_flags, key, klen,
1005 "delete readonly key '%"SVf"' from"
1009 if (d_flags & G_DISCARD)
1012 sv = sv_2mortal(HeVAL(entry));
1013 HeVAL(entry) = &PL_sv_placeholder;
1017 * If a restricted hash, rather than really deleting the entry, put
1018 * a placeholder there. This marks the key as being "approved", so
1019 * we can still access via not-really-existing key without raising
1022 if (SvREADONLY(hv)) {
1023 HeVAL(entry) = &PL_sv_placeholder;
1024 /* We'll be saving this slot, so the number of allocated keys
1025 * doesn't go down, but the number placeholders goes up */
1026 xhv->xhv_placeholders++; /* HvPLACEHOLDERS(hv)++ */
1028 *oentry = HeNEXT(entry);
1030 xhv->xhv_fill--; /* HvFILL(hv)-- */
1031 if (entry == xhv->xhv_eiter /* HvEITER(hv) */)
1034 hv_free_ent(hv, entry);
1035 xhv->xhv_keys--; /* HvKEYS(hv)-- */
1036 if (xhv->xhv_keys == 0)
1037 HvHASKFLAGS_off(hv);
1041 if (SvREADONLY(hv)) {
1042 S_hv_notallowed(aTHX_ k_flags, key, klen,
1043 "delete disallowed key '%"SVf"' from"
1047 if (k_flags & HVhek_FREEKEY)
1053 S_hsplit(pTHX_ HV *hv)
1055 register XPVHV* xhv = (XPVHV*)SvANY(hv);
1056 I32 oldsize = (I32) xhv->xhv_max+1; /* HvMAX(hv)+1 (sick) */
1057 register I32 newsize = oldsize * 2;
1059 register char *a = xhv->xhv_array; /* HvARRAY(hv) */
1063 register HE **oentry;
1064 int longest_chain = 0;
1068 #if defined(STRANGE_MALLOC) || defined(MYMALLOC)
1069 Renew(a, PERL_HV_ARRAY_ALLOC_BYTES(newsize), char);
1075 New(2, a, PERL_HV_ARRAY_ALLOC_BYTES(newsize), char);
1080 Copy(xhv->xhv_array /* HvARRAY(hv) */, a, oldsize * sizeof(HE*), char);
1081 if (oldsize >= 64) {
1082 offer_nice_chunk(xhv->xhv_array /* HvARRAY(hv) */,
1083 PERL_HV_ARRAY_ALLOC_BYTES(oldsize));
1086 Safefree(xhv->xhv_array /* HvARRAY(hv) */);
1090 Zero(&a[oldsize * sizeof(HE*)], (newsize-oldsize) * sizeof(HE*), char); /* zero 2nd half*/
1091 xhv->xhv_max = --newsize; /* HvMAX(hv) = --newsize */
1092 xhv->xhv_array = a; /* HvARRAY(hv) = a */
1095 for (i=0; i<oldsize; i++,aep++) {
1096 int left_length = 0;
1097 int right_length = 0;
1099 if (!*aep) /* non-existent */
1102 for (oentry = aep, entry = *aep; entry; entry = *oentry) {
1103 if ((HeHASH(entry) & newsize) != (U32)i) {
1104 *oentry = HeNEXT(entry);
1105 HeNEXT(entry) = *bep;
1107 xhv->xhv_fill++; /* HvFILL(hv)++ */
1113 oentry = &HeNEXT(entry);
1117 if (!*aep) /* everything moved */
1118 xhv->xhv_fill--; /* HvFILL(hv)-- */
1119 /* I think we don't actually need to keep track of the longest length,
1120 merely flag if anything is too long. But for the moment while
1121 developing this code I'll track it. */
1122 if (left_length > longest_chain)
1123 longest_chain = left_length;
1124 if (right_length > longest_chain)
1125 longest_chain = right_length;
1129 /* Pick your policy for "hashing isn't working" here: */
1130 if (longest_chain <= HV_MAX_LENGTH_BEFORE_SPLIT /* split worked? */
1135 if (hv == PL_strtab) {
1136 /* Urg. Someone is doing something nasty to the string table.
1141 /* Awooga. Awooga. Pathological data. */
1142 /*PerlIO_printf(PerlIO_stderr(), "%p %d of %d with %d/%d buckets\n", hv,
1143 longest_chain, HvTOTALKEYS(hv), HvFILL(hv), 1+HvMAX(hv));*/
1146 Newz(2, a, PERL_HV_ARRAY_ALLOC_BYTES(newsize), char);
1147 was_shared = HvSHAREKEYS(hv);
1150 HvSHAREKEYS_off(hv);
1153 aep = (HE **) xhv->xhv_array;
1155 for (i=0; i<newsize; i++,aep++) {
1158 /* We're going to trash this HE's next pointer when we chain it
1159 into the new hash below, so store where we go next. */
1160 HE *next = HeNEXT(entry);
1164 PERL_HASH_INTERNAL(hash, HeKEY(entry), HeKLEN(entry));
1169 = save_hek_flags(HeKEY(entry), HeKLEN(entry),
1170 hash, HeKFLAGS(entry));
1171 unshare_hek (HeKEY_hek(entry));
1172 HeKEY_hek(entry) = new_hek;
1174 /* Not shared, so simply write the new hash in. */
1175 HeHASH(entry) = hash;
1177 /*PerlIO_printf(PerlIO_stderr(), "%d ", HeKFLAGS(entry));*/
1178 HEK_REHASH_on(HeKEY_hek(entry));
1179 /*PerlIO_printf(PerlIO_stderr(), "%d\n", HeKFLAGS(entry));*/
1181 /* Copy oentry to the correct new chain. */
1182 bep = ((HE**)a) + (hash & (I32) xhv->xhv_max);
1184 xhv->xhv_fill++; /* HvFILL(hv)++ */
1185 HeNEXT(entry) = *bep;
1191 Safefree (xhv->xhv_array);
1192 xhv->xhv_array = a; /* HvARRAY(hv) = a */
1196 Perl_hv_ksplit(pTHX_ HV *hv, IV newmax)
1198 register XPVHV* xhv = (XPVHV*)SvANY(hv);
1199 I32 oldsize = (I32) xhv->xhv_max+1; /* HvMAX(hv)+1 (sick) */
1200 register I32 newsize;
1206 register HE **oentry;
1208 newsize = (I32) newmax; /* possible truncation here */
1209 if (newsize != newmax || newmax <= oldsize)
1211 while ((newsize & (1 + ~newsize)) != newsize) {
1212 newsize &= ~(newsize & (1 + ~newsize)); /* get proper power of 2 */
1214 if (newsize < newmax)
1216 if (newsize < newmax)
1217 return; /* overflow detection */
1219 a = xhv->xhv_array; /* HvARRAY(hv) */
1222 #if defined(STRANGE_MALLOC) || defined(MYMALLOC)
1223 Renew(a, PERL_HV_ARRAY_ALLOC_BYTES(newsize), char);
1229 New(2, a, PERL_HV_ARRAY_ALLOC_BYTES(newsize), char);
1234 Copy(xhv->xhv_array /* HvARRAY(hv) */, a, oldsize * sizeof(HE*), char);
1235 if (oldsize >= 64) {
1236 offer_nice_chunk(xhv->xhv_array /* HvARRAY(hv) */,
1237 PERL_HV_ARRAY_ALLOC_BYTES(oldsize));
1240 Safefree(xhv->xhv_array /* HvARRAY(hv) */);
1243 Zero(&a[oldsize * sizeof(HE*)], (newsize-oldsize) * sizeof(HE*), char); /* zero 2nd half*/
1246 Newz(0, a, PERL_HV_ARRAY_ALLOC_BYTES(newsize), char);
1248 xhv->xhv_max = --newsize; /* HvMAX(hv) = --newsize */
1249 xhv->xhv_array = a; /* HvARRAY(hv) = a */
1250 if (!xhv->xhv_fill /* !HvFILL(hv) */) /* skip rest if no entries */
1254 for (i=0; i<oldsize; i++,aep++) {
1255 if (!*aep) /* non-existent */
1257 for (oentry = aep, entry = *aep; entry; entry = *oentry) {
1258 if ((j = (HeHASH(entry) & newsize)) != i) {
1260 *oentry = HeNEXT(entry);
1261 if (!(HeNEXT(entry) = aep[j]))
1262 xhv->xhv_fill++; /* HvFILL(hv)++ */
1267 oentry = &HeNEXT(entry);
1269 if (!*aep) /* everything moved */
1270 xhv->xhv_fill--; /* HvFILL(hv)-- */
1277 Creates a new HV. The reference count is set to 1.
1286 register XPVHV* xhv;
1288 hv = (HV*)NEWSV(502,0);
1289 sv_upgrade((SV *)hv, SVt_PVHV);
1290 xhv = (XPVHV*)SvANY(hv);
1293 #ifndef NODEFAULT_SHAREKEYS
1294 HvSHAREKEYS_on(hv); /* key-sharing on by default */
1297 xhv->xhv_max = 7; /* HvMAX(hv) = 7 (start with 8 buckets) */
1298 xhv->xhv_fill = 0; /* HvFILL(hv) = 0 */
1299 xhv->xhv_pmroot = 0; /* HvPMROOT(hv) = 0 */
1300 (void)hv_iterinit(hv); /* so each() will start off right */
1305 Perl_newHVhv(pTHX_ HV *ohv)
1308 STRLEN hv_max, hv_fill;
1310 if (!ohv || (hv_fill = HvFILL(ohv)) == 0)
1312 hv_max = HvMAX(ohv);
1314 if (!SvMAGICAL((SV *)ohv)) {
1315 /* It's an ordinary hash, so copy it fast. AMS 20010804 */
1317 bool shared = !!HvSHAREKEYS(ohv);
1318 HE **ents, **oents = (HE **)HvARRAY(ohv);
1320 New(0, a, PERL_HV_ARRAY_ALLOC_BYTES(hv_max+1), char);
1323 /* In each bucket... */
1324 for (i = 0; i <= hv_max; i++) {
1325 HE *prev = NULL, *ent = NULL, *oent = oents[i];
1332 /* Copy the linked list of entries. */
1333 for (oent = oents[i]; oent; oent = HeNEXT(oent)) {
1334 U32 hash = HeHASH(oent);
1335 char *key = HeKEY(oent);
1336 STRLEN len = HeKLEN(oent);
1337 int flags = HeKFLAGS(oent);
1340 HeVAL(ent) = newSVsv(HeVAL(oent));
1342 = shared ? share_hek_flags(key, len, hash, flags)
1343 : save_hek_flags(key, len, hash, flags);
1354 HvFILL(hv) = hv_fill;
1355 HvTOTALKEYS(hv) = HvTOTALKEYS(ohv);
1359 /* Iterate over ohv, copying keys and values one at a time. */
1361 I32 riter = HvRITER(ohv);
1362 HE *eiter = HvEITER(ohv);
1364 /* Can we use fewer buckets? (hv_max is always 2^n-1) */
1365 while (hv_max && hv_max + 1 >= hv_fill * 2)
1366 hv_max = hv_max / 2;
1370 while ((entry = hv_iternext_flags(ohv, 0))) {
1371 hv_store_flags(hv, HeKEY(entry), HeKLEN(entry),
1372 newSVsv(HeVAL(entry)), HeHASH(entry),
1375 HvRITER(ohv) = riter;
1376 HvEITER(ohv) = eiter;
1383 Perl_hv_free_ent(pTHX_ HV *hv, register HE *entry)
1390 if (val && isGV(val) && GvCVu(val) && HvNAME(hv))
1391 PL_sub_generation++; /* may be deletion of method from stash */
1393 if (HeKLEN(entry) == HEf_SVKEY) {
1394 SvREFCNT_dec(HeKEY_sv(entry));
1395 Safefree(HeKEY_hek(entry));
1397 else if (HvSHAREKEYS(hv))
1398 unshare_hek(HeKEY_hek(entry));
1400 Safefree(HeKEY_hek(entry));
1405 Perl_hv_delayfree_ent(pTHX_ HV *hv, register HE *entry)
1409 if (isGV(HeVAL(entry)) && GvCVu(HeVAL(entry)) && HvNAME(hv))
1410 PL_sub_generation++; /* may be deletion of method from stash */
1411 sv_2mortal(HeVAL(entry)); /* free between statements */
1412 if (HeKLEN(entry) == HEf_SVKEY) {
1413 sv_2mortal(HeKEY_sv(entry));
1414 Safefree(HeKEY_hek(entry));
1416 else if (HvSHAREKEYS(hv))
1417 unshare_hek(HeKEY_hek(entry));
1419 Safefree(HeKEY_hek(entry));
1424 =for apidoc hv_clear
1426 Clears a hash, making it empty.
1432 Perl_hv_clear(pTHX_ HV *hv)
1434 register XPVHV* xhv;
1438 DEBUG_A(Perl_hv_assert(aTHX_ hv));
1440 xhv = (XPVHV*)SvANY(hv);
1442 if (SvREADONLY(hv) && xhv->xhv_array != NULL) {
1443 /* restricted hash: convert all keys to placeholders */
1446 for (i = 0; i <= (I32) xhv->xhv_max; i++) {
1447 entry = ((HE**)xhv->xhv_array)[i];
1448 for (; entry; entry = HeNEXT(entry)) {
1449 /* not already placeholder */
1450 if (HeVAL(entry) != &PL_sv_placeholder) {
1451 if (HeVAL(entry) && SvREADONLY(HeVAL(entry))) {
1452 SV* keysv = hv_iterkeysv(entry);
1454 "Attempt to delete readonly key '%"SVf"' from a restricted hash",
1457 SvREFCNT_dec(HeVAL(entry));
1458 HeVAL(entry) = &PL_sv_placeholder;
1459 xhv->xhv_placeholders++; /* HvPLACEHOLDERS(hv)++ */
1467 xhv->xhv_placeholders = 0; /* HvPLACEHOLDERS(hv) = 0 */
1468 if (xhv->xhv_array /* HvARRAY(hv) */)
1469 (void)memzero(xhv->xhv_array /* HvARRAY(hv) */,
1470 (xhv->xhv_max+1 /* HvMAX(hv)+1 */) * sizeof(HE*));
1475 HvHASKFLAGS_off(hv);
1482 =for apidoc hv_clear_placeholders
1484 Clears any placeholders from a hash. If a restricted hash has any of its keys
1485 marked as readonly and the key is subsequently deleted, the key is not actually
1486 deleted but is marked by assigning it a value of &PL_sv_placeholder. This tags
1487 it so it will be ignored by future operations such as iterating over the hash,
1488 but will still allow the hash to have a value reaasigned to the key at some
1489 future point. This function clears any such placeholder keys from the hash.
1490 See Hash::Util::lock_keys() for an example of its use.
1496 Perl_hv_clear_placeholders(pTHX_ HV *hv)
1499 items = (I32)HvPLACEHOLDERS(hv);
1502 I32 riter = HvRITER(hv);
1503 HE *eiter = HvEITER(hv);
1505 /* This may look suboptimal with the items *after* the iternext, but
1506 it's quite deliberate. We only get here with items==0 if we've
1507 just deleted the last placeholder in the hash. If we've just done
1508 that then it means that the hash is in lazy delete mode, and the
1509 HE is now only referenced in our iterator. If we just quit the loop
1510 and discarded our iterator then the HE leaks. So we do the && the
1511 other way to ensure iternext is called just one more time, which
1512 has the side effect of triggering the lazy delete. */
1513 while ((entry = hv_iternext_flags(hv, HV_ITERNEXT_WANTPLACEHOLDERS))
1515 SV *val = hv_iterval(hv, entry);
1517 if (val == &PL_sv_placeholder) {
1519 /* It seems that I have to go back in the front of the hash
1520 API to delete a hash, even though I have a HE structure
1521 pointing to the very entry I want to delete, and could hold
1522 onto the previous HE that points to it. And it's easier to
1523 go in with SVs as I can then specify the precomputed hash,
1524 and don't have fun and games with utf8 keys. */
1525 SV *key = hv_iterkeysv(entry);
1527 hv_delete_ent (hv, key, G_DISCARD, HeHASH(entry));
1531 HvRITER(hv) = riter;
1532 HvEITER(hv) = eiter;
1537 S_hfreeentries(pTHX_ HV *hv)
1539 register HE **array;
1541 register HE *oentry = Null(HE*);
1552 array = HvARRAY(hv);
1553 /* make everyone else think the array is empty, so that the destructors
1554 * called for freed entries can't recusively mess with us */
1555 HvARRAY(hv) = Null(HE**);
1557 ((XPVHV*) SvANY(hv))->xhv_keys = 0;
1563 entry = HeNEXT(entry);
1564 hv_free_ent(hv, oentry);
1569 entry = array[riter];
1572 HvARRAY(hv) = array;
1573 (void)hv_iterinit(hv);
1577 =for apidoc hv_undef
1585 Perl_hv_undef(pTHX_ HV *hv)
1587 register XPVHV* xhv;
1590 DEBUG_A(Perl_hv_assert(aTHX_ hv));
1591 xhv = (XPVHV*)SvANY(hv);
1593 Safefree(xhv->xhv_array /* HvARRAY(hv) */);
1596 hv_delete(PL_stashcache, HvNAME(hv), strlen(HvNAME(hv)), G_DISCARD);
1597 Safefree(HvNAME(hv));
1600 xhv->xhv_max = 7; /* HvMAX(hv) = 7 (it's a normal hash) */
1601 xhv->xhv_array = 0; /* HvARRAY(hv) = 0 */
1602 xhv->xhv_placeholders = 0; /* HvPLACEHOLDERS(hv) = 0 */
1609 =for apidoc hv_iterinit
1611 Prepares a starting point to traverse a hash table. Returns the number of
1612 keys in the hash (i.e. the same as C<HvKEYS(tb)>). The return value is
1613 currently only meaningful for hashes without tie magic.
1615 NOTE: Before version 5.004_65, C<hv_iterinit> used to return the number of
1616 hash buckets that happen to be in use. If you still need that esoteric
1617 value, you can get it through the macro C<HvFILL(tb)>.
1624 Perl_hv_iterinit(pTHX_ HV *hv)
1626 register XPVHV* xhv;
1630 Perl_croak(aTHX_ "Bad hash");
1631 xhv = (XPVHV*)SvANY(hv);
1632 entry = xhv->xhv_eiter; /* HvEITER(hv) */
1633 if (entry && HvLAZYDEL(hv)) { /* was deleted earlier? */
1635 hv_free_ent(hv, entry);
1637 xhv->xhv_riter = -1; /* HvRITER(hv) = -1 */
1638 xhv->xhv_eiter = Null(HE*); /* HvEITER(hv) = Null(HE*) */
1639 /* used to be xhv->xhv_fill before 5.004_65 */
1640 return XHvTOTALKEYS(xhv);
1643 =for apidoc hv_iternext
1645 Returns entries from a hash iterator. See C<hv_iterinit>.
1647 You may call C<hv_delete> or C<hv_delete_ent> on the hash entry that the
1648 iterator currently points to, without losing your place or invalidating your
1649 iterator. Note that in this case the current entry is deleted from the hash
1650 with your iterator holding the last reference to it. Your iterator is flagged
1651 to free the entry on the next call to C<hv_iternext>, so you must not discard
1652 your iterator immediately else the entry will leak - call C<hv_iternext> to
1653 trigger the resource deallocation.
1659 Perl_hv_iternext(pTHX_ HV *hv)
1661 return hv_iternext_flags(hv, 0);
1665 =for apidoc hv_iternext_flags
1667 Returns entries from a hash iterator. See C<hv_iterinit> and C<hv_iternext>.
1668 The C<flags> value will normally be zero; if HV_ITERNEXT_WANTPLACEHOLDERS is
1669 set the placeholders keys (for restricted hashes) will be returned in addition
1670 to normal keys. By default placeholders are automatically skipped over.
1671 Currently a placeholder is implemented with a value that is
1672 C<&Perl_sv_placeholder>. Note that the implementation of placeholders and
1673 restricted hashes may change, and the implementation currently is
1674 insufficiently abstracted for any change to be tidy.
1680 Perl_hv_iternext_flags(pTHX_ HV *hv, I32 flags)
1682 register XPVHV* xhv;
1688 Perl_croak(aTHX_ "Bad hash");
1689 xhv = (XPVHV*)SvANY(hv);
1690 oldentry = entry = xhv->xhv_eiter; /* HvEITER(hv) */
1692 if ((mg = SvTIED_mg((SV*)hv, PERL_MAGIC_tied))) {
1693 SV *key = sv_newmortal();
1695 sv_setsv(key, HeSVKEY_force(entry));
1696 SvREFCNT_dec(HeSVKEY(entry)); /* get rid of previous key */
1702 /* one HE per MAGICAL hash */
1703 xhv->xhv_eiter = entry = new_HE(); /* HvEITER(hv) = new_HE() */
1705 Newz(54, k, HEK_BASESIZE + sizeof(SV*), char);
1707 HeKEY_hek(entry) = hek;
1708 HeKLEN(entry) = HEf_SVKEY;
1710 magic_nextpack((SV*) hv,mg,key);
1712 /* force key to stay around until next time */
1713 HeSVKEY_set(entry, SvREFCNT_inc(key));
1714 return entry; /* beware, hent_val is not set */
1717 SvREFCNT_dec(HeVAL(entry));
1718 Safefree(HeKEY_hek(entry));
1720 xhv->xhv_eiter = Null(HE*); /* HvEITER(hv) = Null(HE*) */
1723 #ifdef DYNAMIC_ENV_FETCH /* set up %ENV for iteration */
1724 if (!entry && SvRMAGICAL((SV*)hv) && mg_find((SV*)hv, PERL_MAGIC_env))
1728 if (!xhv->xhv_array /* !HvARRAY(hv) */)
1729 Newz(506, xhv->xhv_array /* HvARRAY(hv) */,
1730 PERL_HV_ARRAY_ALLOC_BYTES(xhv->xhv_max+1 /* HvMAX(hv)+1 */),
1732 /* At start of hash, entry is NULL. */
1735 entry = HeNEXT(entry);
1736 if (!(flags & HV_ITERNEXT_WANTPLACEHOLDERS)) {
1738 * Skip past any placeholders -- don't want to include them in
1741 while (entry && HeVAL(entry) == &PL_sv_placeholder) {
1742 entry = HeNEXT(entry);
1747 /* OK. Come to the end of the current list. Grab the next one. */
1749 xhv->xhv_riter++; /* HvRITER(hv)++ */
1750 if (xhv->xhv_riter > (I32)xhv->xhv_max /* HvRITER(hv) > HvMAX(hv) */) {
1751 /* There is no next one. End of the hash. */
1752 xhv->xhv_riter = -1; /* HvRITER(hv) = -1 */
1755 /* entry = (HvARRAY(hv))[HvRITER(hv)]; */
1756 entry = ((HE**)xhv->xhv_array)[xhv->xhv_riter];
1758 if (!(flags & HV_ITERNEXT_WANTPLACEHOLDERS)) {
1759 /* If we have an entry, but it's a placeholder, don't count it.
1761 while (entry && HeVAL(entry) == &PL_sv_placeholder)
1762 entry = HeNEXT(entry);
1764 /* Will loop again if this linked list starts NULL
1765 (for HV_ITERNEXT_WANTPLACEHOLDERS)
1766 or if we run through it and find only placeholders. */
1769 if (oldentry && HvLAZYDEL(hv)) { /* was deleted earlier? */
1771 hv_free_ent(hv, oldentry);
1774 /*if (HvREHASH(hv) && entry && !HeKREHASH(entry))
1775 PerlIO_printf(PerlIO_stderr(), "Awooga %p %p\n", hv, entry);*/
1777 xhv->xhv_eiter = entry; /* HvEITER(hv) = entry */
1782 =for apidoc hv_iterkey
1784 Returns the key from the current position of the hash iterator. See
1791 Perl_hv_iterkey(pTHX_ register HE *entry, I32 *retlen)
1793 if (HeKLEN(entry) == HEf_SVKEY) {
1795 char *p = SvPV(HeKEY_sv(entry), len);
1800 *retlen = HeKLEN(entry);
1801 return HeKEY(entry);
1805 /* unlike hv_iterval(), this always returns a mortal copy of the key */
1807 =for apidoc hv_iterkeysv
1809 Returns the key as an C<SV*> from the current position of the hash
1810 iterator. The return value will always be a mortal copy of the key. Also
1817 Perl_hv_iterkeysv(pTHX_ register HE *entry)
1819 if (HeKLEN(entry) != HEf_SVKEY) {
1820 HEK *hek = HeKEY_hek(entry);
1821 int flags = HEK_FLAGS(hek);
1824 if (flags & HVhek_WASUTF8) {
1826 Andreas would like keys he put in as utf8 to come back as utf8
1828 STRLEN utf8_len = HEK_LEN(hek);
1829 U8 *as_utf8 = bytes_to_utf8 ((U8*)HEK_KEY(hek), &utf8_len);
1831 sv = newSVpvn ((char*)as_utf8, utf8_len);
1833 Safefree (as_utf8); /* bytes_to_utf8() allocates a new string */
1834 } else if (flags & HVhek_REHASH) {
1835 /* We don't have a pointer to the hv, so we have to replicate the
1836 flag into every HEK. This hv is using custom a hasing
1837 algorithm. Hence we can't return a shared string scalar, as
1838 that would contain the (wrong) hash value, and might get passed
1839 into an hv routine with a regular hash */
1841 sv = newSVpvn (HEK_KEY(hek), HEK_LEN(hek));
1845 sv = newSVpvn_share(HEK_KEY(hek),
1846 (HEK_UTF8(hek) ? -HEK_LEN(hek) : HEK_LEN(hek)),
1849 return sv_2mortal(sv);
1851 return sv_mortalcopy(HeKEY_sv(entry));
1855 =for apidoc hv_iterval
1857 Returns the value from the current position of the hash iterator. See
1864 Perl_hv_iterval(pTHX_ HV *hv, register HE *entry)
1866 if (SvRMAGICAL(hv)) {
1867 if (mg_find((SV*)hv, PERL_MAGIC_tied)) {
1868 SV* sv = sv_newmortal();
1869 if (HeKLEN(entry) == HEf_SVKEY)
1870 mg_copy((SV*)hv, sv, (char*)HeKEY_sv(entry), HEf_SVKEY);
1871 else mg_copy((SV*)hv, sv, HeKEY(entry), HeKLEN(entry));
1875 return HeVAL(entry);
1879 =for apidoc hv_iternextsv
1881 Performs an C<hv_iternext>, C<hv_iterkey>, and C<hv_iterval> in one
1888 Perl_hv_iternextsv(pTHX_ HV *hv, char **key, I32 *retlen)
1891 if ( (he = hv_iternext_flags(hv, 0)) == NULL)
1893 *key = hv_iterkey(he, retlen);
1894 return hv_iterval(hv, he);
1898 =for apidoc hv_magic
1900 Adds magic to a hash. See C<sv_magic>.
1906 Perl_hv_magic(pTHX_ HV *hv, GV *gv, int how)
1908 sv_magic((SV*)hv, (SV*)gv, how, Nullch, 0);
1911 #if 0 /* use the macro from hv.h instead */
1914 Perl_sharepvn(pTHX_ const char *sv, I32 len, U32 hash)
1916 return HEK_KEY(share_hek(sv, len, hash));
1921 /* possibly free a shared string if no one has access to it
1922 * len and hash must both be valid for str.
1925 Perl_unsharepvn(pTHX_ const char *str, I32 len, U32 hash)
1927 unshare_hek_or_pvn (NULL, str, len, hash);
1932 Perl_unshare_hek(pTHX_ HEK *hek)
1934 unshare_hek_or_pvn(hek, NULL, 0, 0);
1937 /* possibly free a shared string if no one has access to it
1938 hek if non-NULL takes priority over the other 3, else str, len and hash
1939 are used. If so, len and hash must both be valid for str.
1942 S_unshare_hek_or_pvn(pTHX_ HEK *hek, const char *str, I32 len, U32 hash)
1944 register XPVHV* xhv;
1946 register HE **oentry;
1949 bool is_utf8 = FALSE;
1951 const char *save = str;
1954 hash = HEK_HASH(hek);
1955 } else if (len < 0) {
1956 STRLEN tmplen = -len;
1958 /* See the note in hv_fetch(). --jhi */
1959 str = (char*)bytes_from_utf8((U8*)str, &tmplen, &is_utf8);
1962 k_flags = HVhek_UTF8;
1964 k_flags |= HVhek_WASUTF8 | HVhek_FREEKEY;
1967 /* what follows is the moral equivalent of:
1968 if ((Svp = hv_fetch(PL_strtab, tmpsv, FALSE, hash))) {
1969 if (--*Svp == Nullsv)
1970 hv_delete(PL_strtab, str, len, G_DISCARD, hash);
1972 xhv = (XPVHV*)SvANY(PL_strtab);
1973 /* assert(xhv_array != 0) */
1975 /* oentry = &(HvARRAY(hv))[hash & (I32) HvMAX(hv)]; */
1976 oentry = &((HE**)xhv->xhv_array)[hash & (I32) xhv->xhv_max];
1978 for (entry = *oentry; entry; i=0, oentry = &HeNEXT(entry), entry = *oentry) {
1979 if (HeKEY_hek(entry) != hek)
1985 int flags_masked = k_flags & HVhek_MASK;
1986 for (entry = *oentry; entry; i=0, oentry = &HeNEXT(entry), entry = *oentry) {
1987 if (HeHASH(entry) != hash) /* strings can't be equal */
1989 if (HeKLEN(entry) != len)
1991 if (HeKEY(entry) != str && memNE(HeKEY(entry),str,len)) /* is this it? */
1993 if (HeKFLAGS(entry) != flags_masked)
2001 if (--HeVAL(entry) == Nullsv) {
2002 *oentry = HeNEXT(entry);
2004 xhv->xhv_fill--; /* HvFILL(hv)-- */
2005 Safefree(HeKEY_hek(entry));
2007 xhv->xhv_keys--; /* HvKEYS(hv)-- */
2011 UNLOCK_STRTAB_MUTEX;
2012 if (!found && ckWARN_d(WARN_INTERNAL))
2013 Perl_warner(aTHX_ packWARN(WARN_INTERNAL),
2014 "Attempt to free non-existent shared string '%s'%s",
2015 hek ? HEK_KEY(hek) : str,
2016 (k_flags & HVhek_UTF8) ? " (utf8)" : "");
2017 if (k_flags & HVhek_FREEKEY)
2021 /* get a (constant) string ptr from the global string table
2022 * string will get added if it is not already there.
2023 * len and hash must both be valid for str.
2026 Perl_share_hek(pTHX_ const char *str, I32 len, register U32 hash)
2028 bool is_utf8 = FALSE;
2030 const char *save = str;
2033 STRLEN tmplen = -len;
2035 /* See the note in hv_fetch(). --jhi */
2036 str = (char*)bytes_from_utf8((U8*)str, &tmplen, &is_utf8);
2038 /* If we were able to downgrade here, then than means that we were passed
2039 in a key which only had chars 0-255, but was utf8 encoded. */
2042 /* If we found we were able to downgrade the string to bytes, then
2043 we should flag that it needs upgrading on keys or each. Also flag
2044 that we need share_hek_flags to free the string. */
2046 flags |= HVhek_WASUTF8 | HVhek_FREEKEY;
2049 return share_hek_flags (str, len, hash, flags);
2053 S_share_hek_flags(pTHX_ const char *str, I32 len, register U32 hash, int flags)
2055 register XPVHV* xhv;
2057 register HE **oentry;
2060 int flags_masked = flags & HVhek_MASK;
2062 /* what follows is the moral equivalent of:
2064 if (!(Svp = hv_fetch(PL_strtab, str, len, FALSE)))
2065 hv_store(PL_strtab, str, len, Nullsv, hash);
2067 Can't rehash the shared string table, so not sure if it's worth
2068 counting the number of entries in the linked list
2070 xhv = (XPVHV*)SvANY(PL_strtab);
2071 /* assert(xhv_array != 0) */
2073 /* oentry = &(HvARRAY(hv))[hash & (I32) HvMAX(hv)]; */
2074 oentry = &((HE**)xhv->xhv_array)[hash & (I32) xhv->xhv_max];
2075 for (entry = *oentry; entry; i=0, entry = HeNEXT(entry)) {
2076 if (HeHASH(entry) != hash) /* strings can't be equal */
2078 if (HeKLEN(entry) != len)
2080 if (HeKEY(entry) != str && memNE(HeKEY(entry),str,len)) /* is this it? */
2082 if (HeKFLAGS(entry) != flags_masked)
2089 HeKEY_hek(entry) = save_hek_flags(str, len, hash, flags_masked);
2090 HeVAL(entry) = Nullsv;
2091 HeNEXT(entry) = *oentry;
2093 xhv->xhv_keys++; /* HvKEYS(hv)++ */
2094 if (i) { /* initial entry? */
2095 xhv->xhv_fill++; /* HvFILL(hv)++ */
2096 } else if (xhv->xhv_keys > (IV)xhv->xhv_max /* HvKEYS(hv) > HvMAX(hv) */) {
2101 ++HeVAL(entry); /* use value slot as REFCNT */
2102 UNLOCK_STRTAB_MUTEX;
2104 if (flags & HVhek_FREEKEY)
2107 return HeKEY_hek(entry);
2112 =for apidoc hv_assert
2114 Check that a hash is in an internally consistent state.
2120 Perl_hv_assert(pTHX_ HV *hv)
2124 int placeholders = 0;
2127 I32 riter = HvRITER(hv);
2128 HE *eiter = HvEITER(hv);
2130 (void)hv_iterinit(hv);
2132 while ((entry = hv_iternext_flags(hv, HV_ITERNEXT_WANTPLACEHOLDERS))) {
2133 /* sanity check the values */
2134 if (HeVAL(entry) == &PL_sv_placeholder) {
2139 /* sanity check the keys */
2140 if (HeSVKEY(entry)) {
2141 /* Don't know what to check on SV keys. */
2142 } else if (HeKUTF8(entry)) {
2144 if (HeKWASUTF8(entry)) {
2145 PerlIO_printf(Perl_debug_log,
2146 "hash key has both WASUFT8 and UTF8: '%.*s'\n",
2147 (int) HeKLEN(entry), HeKEY(entry));
2150 } else if (HeKWASUTF8(entry)) {
2154 if (!SvTIED_mg((SV*)hv, PERL_MAGIC_tied)) {
2155 if (HvUSEDKEYS(hv) != real) {
2156 PerlIO_printf(Perl_debug_log, "Count %d key(s), but hash reports %d\n",
2157 (int) real, (int) HvUSEDKEYS(hv));
2160 if (HvPLACEHOLDERS(hv) != placeholders) {
2161 PerlIO_printf(Perl_debug_log,
2162 "Count %d placeholder(s), but hash reports %d\n",
2163 (int) placeholders, (int) HvPLACEHOLDERS(hv));
2167 if (withflags && ! HvHASKFLAGS(hv)) {
2168 PerlIO_printf(Perl_debug_log,
2169 "Hash has HASKFLAGS off but I count %d key(s) with flags\n",
2176 HvRITER(hv) = riter; /* Restore hash iterator state */
2177 HvEITER(hv) = eiter;