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 key = SvPV(keysv, klen);
386 is_utf8 = (SvUTF8(keysv) != 0);
388 is_utf8 = ((flags & HVhek_UTF8) ? TRUE : FALSE);
391 xhv = (XPVHV*)SvANY(hv);
393 if (SvRMAGICAL(hv) && !(action & (HV_FETCH_ISSTORE|HV_FETCH_ISEXISTS)))
395 if (mg_find((SV*)hv, PERL_MAGIC_tied) || SvGMAGICAL((SV*)hv)) {
398 /* XXX should be able to skimp on the HE/HEK here when
399 HV_FETCH_JUST_SV is true. */
402 keysv = newSVpvn(key, klen);
407 keysv = newSVsv(keysv);
409 mg_copy((SV*)hv, sv, (char *)keysv, HEf_SVKEY);
411 /* grab a fake HE/HEK pair from the pool or make a new one */
412 entry = PL_hv_fetch_ent_mh;
414 PL_hv_fetch_ent_mh = HeNEXT(entry);
418 New(54, k, HEK_BASESIZE + sizeof(SV*), char);
419 HeKEY_hek(entry) = (HEK*)k;
421 HeNEXT(entry) = Nullhe;
422 HeSVKEY_set(entry, keysv);
424 sv_upgrade(sv, SVt_PVLV);
426 /* so we can free entry when freeing sv */
427 LvTARG(sv) = (SV*)entry;
429 /* XXX remove at some point? */
430 if (flags & HVhek_FREEKEY)
435 #ifdef ENV_IS_CASELESS
436 else if (mg_find((SV*)hv, PERL_MAGIC_env)) {
438 for (i = 0; i < klen; ++i)
439 if (isLOWER(key[i])) {
440 const char *keysave = key;
441 /* Will need to free this, so set FREEKEY flag
442 on call to hv_fetch_common. */
443 key = savepvn(key,klen);
444 key = (const char*)strupr((char*)key);
446 if (flags & HVhek_FREEKEY)
449 /* This isn't strictly the same as the old hv_fetch
450 magic, which made a call to hv_fetch, followed
451 by a call to hv_store if that failed and lvalue
453 Which I believe could have been done by simply
454 passing the lvalue through to the first hv_fetch.
455 So I will do that here. */
456 return hv_fetch_common(hv, Nullsv, key, klen,
463 else if (SvRMAGICAL(hv) && (action & HV_FETCH_ISEXISTS)) {
464 if (mg_find((SV*)hv, PERL_MAGIC_tied) || SvGMAGICAL((SV*)hv)) {
466 /* I don't understand why hv_exists_ent has svret and sv,
467 whereas hv_exists only had one. */
468 svret = sv_newmortal();
471 if (keysv || is_utf8) {
473 keysv = newSVpvn(key, klen);
476 keysv = newSVsv(keysv);
478 mg_copy((SV*)hv, sv, (char *)sv_2mortal(keysv), HEf_SVKEY);
480 mg_copy((SV*)hv, sv, key, klen);
482 if (flags & HVhek_FREEKEY)
484 magic_existspack(svret, mg_find(sv, PERL_MAGIC_tiedelem));
485 /* This cast somewhat evil, but I'm merely using NULL/
486 not NULL to return the boolean exists.
487 And I know hv is not NULL. */
488 return SvTRUE(svret) ? (HE *)hv : NULL;
490 #ifdef ENV_IS_CASELESS
491 else if (mg_find((SV*)hv, PERL_MAGIC_env)) {
492 /* XXX This code isn't UTF8 clean. */
493 const char *keysave = key;
494 /* Will need to free this, so set FREEKEY flag. */
495 key = savepvn(key,klen);
496 key = (const char*)strupr((char*)key);
500 if (flags & HVhek_FREEKEY) {
503 flags |= HVhek_FREEKEY;
507 else if (action & HV_FETCH_ISSTORE) {
510 hv_magic_check (hv, &needs_copy, &needs_store);
512 bool save_taint = PL_tainted;
513 if (keysv || is_utf8) {
515 keysv = newSVpvn(key, klen);
519 PL_tainted = SvTAINTED(keysv);
520 keysv = sv_2mortal(newSVsv(keysv));
521 mg_copy((SV*)hv, val, (char*)keysv, HEf_SVKEY);
523 mg_copy((SV*)hv, val, key, klen);
526 TAINT_IF(save_taint);
527 if (!xhv->xhv_array /* !HvARRAY(hv) */ && !needs_store) {
528 if (flags & HVhek_FREEKEY)
532 #ifdef ENV_IS_CASELESS
533 else if (mg_find((SV*)hv, PERL_MAGIC_env)) {
534 /* XXX This code isn't UTF8 clean. */
535 const char *keysave = key;
536 /* Will need to free this, so set FREEKEY flag. */
537 key = savepvn(key,klen);
538 key = (const char*)strupr((char*)key);
542 if (flags & HVhek_FREEKEY) {
545 flags |= HVhek_FREEKEY;
552 if (!xhv->xhv_array /* !HvARRAY(hv) */) {
553 if ((action & (HV_FETCH_LVALUE | HV_FETCH_ISSTORE))
554 #ifdef DYNAMIC_ENV_FETCH /* if it's an %ENV lookup, we may get it on the fly */
555 || (SvRMAGICAL((SV*)hv) && mg_find((SV*)hv, PERL_MAGIC_env))
558 Newz(503, xhv->xhv_array /* HvARRAY(hv) */,
559 PERL_HV_ARRAY_ALLOC_BYTES(xhv->xhv_max+1 /* HvMAX(hv)+1 */),
561 #ifdef DYNAMIC_ENV_FETCH
562 else if (action & HV_FETCH_ISEXISTS) {
563 /* for an %ENV exists, if we do an insert it's by a recursive
564 store call, so avoid creating HvARRAY(hv) right now. */
568 /* XXX remove at some point? */
569 if (flags & HVhek_FREEKEY)
577 const char *keysave = key;
578 key = (char*)bytes_from_utf8((U8*)key, &klen, &is_utf8);
582 flags &= ~HVhek_UTF8;
583 if (key != keysave) {
584 if (flags & HVhek_FREEKEY)
586 flags |= HVhek_WASUTF8 | HVhek_FREEKEY;
591 PERL_HASH_INTERNAL(hash, key, klen);
592 /* We don't have a pointer to the hv, so we have to replicate the
593 flag into every HEK, so that hv_iterkeysv can see it. */
594 /* And yes, you do need this even though you are not "storing" because
595 you can flip the flags below if doing an lval lookup. (And that
596 was put in to give the semantics Andreas was expecting.) */
597 flags |= HVhek_REHASH;
599 if (keysv && (SvIsCOW_shared_hash(keysv))) {
602 PERL_HASH(hash, key, klen);
606 masked_flags = (flags & HVhek_MASK);
609 #ifdef DYNAMIC_ENV_FETCH
610 if (!xhv->xhv_array /* !HvARRAY(hv) */) entry = Null(HE*);
614 /* entry = (HvARRAY(hv))[hash & (I32) HvMAX(hv)]; */
615 entry = ((HE**)xhv->xhv_array)[hash & (I32) xhv->xhv_max];
617 for (; entry; ++n_links, entry = HeNEXT(entry)) {
618 if (HeHASH(entry) != hash) /* strings can't be equal */
620 if (HeKLEN(entry) != (I32)klen)
622 if (HeKEY(entry) != key && memNE(HeKEY(entry),key,klen)) /* is this it? */
624 if ((HeKFLAGS(entry) ^ masked_flags) & HVhek_UTF8)
627 if (action & (HV_FETCH_LVALUE|HV_FETCH_ISSTORE)) {
628 if (HeKFLAGS(entry) != masked_flags) {
629 /* We match if HVhek_UTF8 bit in our flags and hash key's
630 match. But if entry was set previously with HVhek_WASUTF8
631 and key now doesn't (or vice versa) then we should change
632 the key's flag, as this is assignment. */
633 if (HvSHAREKEYS(hv)) {
634 /* Need to swap the key we have for a key with the flags we
635 need. As keys are shared we can't just write to the
636 flag, so we share the new one, unshare the old one. */
637 HEK *new_hek = share_hek_flags(key, klen, hash,
639 unshare_hek (HeKEY_hek(entry));
640 HeKEY_hek(entry) = new_hek;
643 HeKFLAGS(entry) = masked_flags;
644 if (masked_flags & HVhek_ENABLEHVKFLAGS)
647 if (HeVAL(entry) == &PL_sv_placeholder) {
648 /* yes, can store into placeholder slot */
649 if (action & HV_FETCH_LVALUE) {
651 /* This preserves behaviour with the old hv_fetch
652 implementation which at this point would bail out
653 with a break; (at "if we find a placeholder, we
654 pretend we haven't found anything")
656 That break mean that if a placeholder were found, it
657 caused a call into hv_store, which in turn would
658 check magic, and if there is no magic end up pretty
659 much back at this point (in hv_store's code). */
662 /* LVAL fetch which actaully needs a store. */
664 xhv->xhv_placeholders--;
667 if (val != &PL_sv_placeholder)
668 xhv->xhv_placeholders--;
671 } else if (action & HV_FETCH_ISSTORE) {
672 SvREFCNT_dec(HeVAL(entry));
675 } else if (HeVAL(entry) == &PL_sv_placeholder) {
676 /* if we find a placeholder, we pretend we haven't found
680 if (flags & HVhek_FREEKEY)
684 #ifdef DYNAMIC_ENV_FETCH /* %ENV lookup? If so, try to fetch the value now */
685 if (!(action & HV_FETCH_ISSTORE)
686 && SvRMAGICAL((SV*)hv) && mg_find((SV*)hv, PERL_MAGIC_env)) {
688 char *env = PerlEnv_ENVgetenv_len(key,&len);
690 sv = newSVpvn(env,len);
692 return hv_fetch_common(hv,keysv,key,klen,flags,HV_FETCH_ISSTORE,sv,
698 if (!entry && SvREADONLY(hv) && !(action & HV_FETCH_ISEXISTS)) {
699 S_hv_notallowed(aTHX_ flags, key, klen,
700 "access disallowed key '%"SVf"' in"
703 if (!(action & (HV_FETCH_LVALUE|HV_FETCH_ISSTORE))) {
704 /* Not doing some form of store, so return failure. */
705 if (flags & HVhek_FREEKEY)
709 if (action & HV_FETCH_LVALUE) {
712 /* At this point the old hv_fetch code would call to hv_store,
713 which in turn might do some tied magic. So we need to make that
714 magic check happen. */
715 /* gonna assign to this, so it better be there */
716 return hv_fetch_common(hv, keysv, key, klen, flags,
717 HV_FETCH_ISSTORE, val, hash);
718 /* XXX Surely that could leak if the fetch-was-store fails?
719 Just like the hv_fetch. */
723 /* Welcome to hv_store... */
725 if (!xhv->xhv_array) {
726 /* Not sure if we can get here. I think the only case of oentry being
727 NULL is for %ENV with dynamic env fetch. But that should disappear
728 with magic in the previous code. */
729 Newz(503, xhv->xhv_array /* HvARRAY(hv) */,
730 PERL_HV_ARRAY_ALLOC_BYTES(xhv->xhv_max+1 /* HvMAX(hv)+1 */),
734 oentry = &((HE**)xhv->xhv_array)[hash & (I32) xhv->xhv_max];
737 /* share_hek_flags will do the free for us. This might be considered
740 HeKEY_hek(entry) = share_hek_flags(key, klen, hash, flags);
741 else /* gotta do the real thing */
742 HeKEY_hek(entry) = save_hek_flags(key, klen, hash, flags);
744 HeNEXT(entry) = *oentry;
747 if (val == &PL_sv_placeholder)
748 xhv->xhv_placeholders++;
749 if (masked_flags & HVhek_ENABLEHVKFLAGS)
752 xhv->xhv_keys++; /* HvKEYS(hv)++ */
753 if (!n_links) { /* initial entry? */
754 xhv->xhv_fill++; /* HvFILL(hv)++ */
755 } else if ((xhv->xhv_keys > (IV)xhv->xhv_max)
756 || ((n_links > HV_MAX_LENGTH_BEFORE_SPLIT) && !HvREHASH(hv))) {
757 /* Use only the old HvKEYS(hv) > HvMAX(hv) condition to limit bucket
758 splits on a rehashed hash, as we're not going to split it again,
759 and if someone is lucky (evil) enough to get all the keys in one
760 list they could exhaust our memory as we repeatedly double the
761 number of buckets on every entry. Linear search feels a less worse
770 S_hv_magic_check(pTHX_ HV *hv, bool *needs_copy, bool *needs_store)
772 MAGIC *mg = SvMAGIC(hv);
776 if (isUPPER(mg->mg_type)) {
778 switch (mg->mg_type) {
779 case PERL_MAGIC_tied:
781 *needs_store = FALSE;
784 mg = mg->mg_moremagic;
789 =for apidoc hv_scalar
791 Evaluates the hash in scalar context and returns the result. Handles magic when the hash is tied.
797 Perl_hv_scalar(pTHX_ HV *hv)
802 if ((SvRMAGICAL(hv) && (mg = mg_find((SV*)hv, PERL_MAGIC_tied)))) {
803 sv = magic_scalarpack(hv, mg);
809 Perl_sv_setpvf(aTHX_ sv, "%ld/%ld",
810 (long)HvFILL(hv), (long)HvMAX(hv) + 1);
818 =for apidoc hv_delete
820 Deletes a key/value pair in the hash. The value SV is removed from the
821 hash and returned to the caller. The C<klen> is the length of the key.
822 The C<flags> value will normally be zero; if set to G_DISCARD then NULL
829 Perl_hv_delete(pTHX_ HV *hv, const char *key, I32 klen_i32, I32 flags)
836 k_flags |= HVhek_UTF8;
840 return hv_delete_common(hv, NULL, key, klen, k_flags, flags, 0);
844 =for apidoc hv_delete_ent
846 Deletes a key/value pair in the hash. The value SV is removed from the
847 hash and returned to the caller. The C<flags> value will normally be zero;
848 if set to G_DISCARD then NULL will be returned. C<hash> can be a valid
849 precomputed hash value, or 0 to ask for it to be computed.
855 Perl_hv_delete_ent(pTHX_ HV *hv, SV *keysv, I32 flags, U32 hash)
857 return hv_delete_common(hv, keysv, NULL, 0, 0, flags, hash);
861 S_hv_delete_common(pTHX_ HV *hv, SV *keysv, const char *key, STRLEN klen,
862 int k_flags, I32 d_flags, U32 hash)
867 register HE **oentry;
876 key = SvPV(keysv, klen);
878 is_utf8 = (SvUTF8(keysv) != 0);
880 is_utf8 = ((k_flags & HVhek_UTF8) ? TRUE : FALSE);
883 if (SvRMAGICAL(hv)) {
886 hv_magic_check (hv, &needs_copy, &needs_store);
889 entry = hv_fetch_common(hv, keysv, key, klen,
890 k_flags & ~HVhek_FREEKEY, HV_FETCH_LVALUE,
892 sv = entry ? HeVAL(entry) : NULL;
898 if (mg_find(sv, PERL_MAGIC_tiedelem)) {
899 /* No longer an element */
900 sv_unmagic(sv, PERL_MAGIC_tiedelem);
903 return Nullsv; /* element cannot be deleted */
905 #ifdef ENV_IS_CASELESS
906 else if (mg_find((SV*)hv, PERL_MAGIC_env)) {
907 /* XXX This code isn't UTF8 clean. */
908 keysv = sv_2mortal(newSVpvn(key,klen));
909 if (k_flags & HVhek_FREEKEY) {
912 key = strupr(SvPVX(keysv));
921 xhv = (XPVHV*)SvANY(hv);
922 if (!xhv->xhv_array /* !HvARRAY(hv) */)
926 const char *keysave = key;
927 key = (char*)bytes_from_utf8((U8*)key, &klen, &is_utf8);
930 k_flags |= HVhek_UTF8;
932 k_flags &= ~HVhek_UTF8;
933 if (key != keysave) {
934 if (k_flags & HVhek_FREEKEY) {
935 /* This shouldn't happen if our caller does what we expect,
936 but strictly the API allows it. */
939 k_flags |= HVhek_WASUTF8 | HVhek_FREEKEY;
941 HvHASKFLAGS_on((SV*)hv);
945 PERL_HASH_INTERNAL(hash, key, klen);
947 if (keysv && (SvIsCOW_shared_hash(keysv))) {
950 PERL_HASH(hash, key, klen);
952 PERL_HASH(hash, key, klen);
955 masked_flags = (k_flags & HVhek_MASK);
957 /* oentry = &(HvARRAY(hv))[hash & (I32) HvMAX(hv)]; */
958 oentry = &((HE**)xhv->xhv_array)[hash & (I32) xhv->xhv_max];
961 for (; entry; i=0, oentry = &HeNEXT(entry), entry = *oentry) {
962 if (HeHASH(entry) != hash) /* strings can't be equal */
964 if (HeKLEN(entry) != (I32)klen)
966 if (HeKEY(entry) != key && memNE(HeKEY(entry),key,klen)) /* is this it? */
968 if ((HeKFLAGS(entry) ^ masked_flags) & HVhek_UTF8)
970 if (k_flags & HVhek_FREEKEY)
973 /* if placeholder is here, it's already been deleted.... */
974 if (HeVAL(entry) == &PL_sv_placeholder)
977 return Nullsv; /* if still SvREADONLY, leave it deleted. */
979 /* okay, really delete the placeholder. */
980 *oentry = HeNEXT(entry);
982 xhv->xhv_fill--; /* HvFILL(hv)-- */
983 if (entry == xhv->xhv_eiter /* HvEITER(hv) */)
986 hv_free_ent(hv, entry);
987 xhv->xhv_keys--; /* HvKEYS(hv)-- */
988 if (xhv->xhv_keys == 0)
990 xhv->xhv_placeholders--;
993 else if (SvREADONLY(hv) && HeVAL(entry) && SvREADONLY(HeVAL(entry))) {
994 S_hv_notallowed(aTHX_ k_flags, key, klen,
995 "delete readonly key '%"SVf"' from"
999 if (d_flags & G_DISCARD)
1002 sv = sv_2mortal(HeVAL(entry));
1003 HeVAL(entry) = &PL_sv_placeholder;
1007 * If a restricted hash, rather than really deleting the entry, put
1008 * a placeholder there. This marks the key as being "approved", so
1009 * we can still access via not-really-existing key without raising
1012 if (SvREADONLY(hv)) {
1013 HeVAL(entry) = &PL_sv_placeholder;
1014 /* We'll be saving this slot, so the number of allocated keys
1015 * doesn't go down, but the number placeholders goes up */
1016 xhv->xhv_placeholders++; /* HvPLACEHOLDERS(hv)++ */
1018 *oentry = HeNEXT(entry);
1020 xhv->xhv_fill--; /* HvFILL(hv)-- */
1021 if (entry == xhv->xhv_eiter /* HvEITER(hv) */)
1024 hv_free_ent(hv, entry);
1025 xhv->xhv_keys--; /* HvKEYS(hv)-- */
1026 if (xhv->xhv_keys == 0)
1027 HvHASKFLAGS_off(hv);
1031 if (SvREADONLY(hv)) {
1032 S_hv_notallowed(aTHX_ k_flags, key, klen,
1033 "delete disallowed key '%"SVf"' from"
1037 if (k_flags & HVhek_FREEKEY)
1043 S_hsplit(pTHX_ HV *hv)
1045 register XPVHV* xhv = (XPVHV*)SvANY(hv);
1046 I32 oldsize = (I32) xhv->xhv_max+1; /* HvMAX(hv)+1 (sick) */
1047 register I32 newsize = oldsize * 2;
1049 register char *a = xhv->xhv_array; /* HvARRAY(hv) */
1053 register HE **oentry;
1054 int longest_chain = 0;
1058 #if defined(STRANGE_MALLOC) || defined(MYMALLOC)
1059 Renew(a, PERL_HV_ARRAY_ALLOC_BYTES(newsize), char);
1065 New(2, a, PERL_HV_ARRAY_ALLOC_BYTES(newsize), char);
1070 Copy(xhv->xhv_array /* HvARRAY(hv) */, a, oldsize * sizeof(HE*), char);
1071 if (oldsize >= 64) {
1072 offer_nice_chunk(xhv->xhv_array /* HvARRAY(hv) */,
1073 PERL_HV_ARRAY_ALLOC_BYTES(oldsize));
1076 Safefree(xhv->xhv_array /* HvARRAY(hv) */);
1080 Zero(&a[oldsize * sizeof(HE*)], (newsize-oldsize) * sizeof(HE*), char); /* zero 2nd half*/
1081 xhv->xhv_max = --newsize; /* HvMAX(hv) = --newsize */
1082 xhv->xhv_array = a; /* HvARRAY(hv) = a */
1085 for (i=0; i<oldsize; i++,aep++) {
1086 int left_length = 0;
1087 int right_length = 0;
1089 if (!*aep) /* non-existent */
1092 for (oentry = aep, entry = *aep; entry; entry = *oentry) {
1093 if ((HeHASH(entry) & newsize) != (U32)i) {
1094 *oentry = HeNEXT(entry);
1095 HeNEXT(entry) = *bep;
1097 xhv->xhv_fill++; /* HvFILL(hv)++ */
1103 oentry = &HeNEXT(entry);
1107 if (!*aep) /* everything moved */
1108 xhv->xhv_fill--; /* HvFILL(hv)-- */
1109 /* I think we don't actually need to keep track of the longest length,
1110 merely flag if anything is too long. But for the moment while
1111 developing this code I'll track it. */
1112 if (left_length > longest_chain)
1113 longest_chain = left_length;
1114 if (right_length > longest_chain)
1115 longest_chain = right_length;
1119 /* Pick your policy for "hashing isn't working" here: */
1120 if (longest_chain <= HV_MAX_LENGTH_BEFORE_SPLIT /* split worked? */
1125 if (hv == PL_strtab) {
1126 /* Urg. Someone is doing something nasty to the string table.
1131 /* Awooga. Awooga. Pathological data. */
1132 /*PerlIO_printf(PerlIO_stderr(), "%p %d of %d with %d/%d buckets\n", hv,
1133 longest_chain, HvTOTALKEYS(hv), HvFILL(hv), 1+HvMAX(hv));*/
1136 Newz(2, a, PERL_HV_ARRAY_ALLOC_BYTES(newsize), char);
1137 was_shared = HvSHAREKEYS(hv);
1140 HvSHAREKEYS_off(hv);
1143 aep = (HE **) xhv->xhv_array;
1145 for (i=0; i<newsize; i++,aep++) {
1148 /* We're going to trash this HE's next pointer when we chain it
1149 into the new hash below, so store where we go next. */
1150 HE *next = HeNEXT(entry);
1154 PERL_HASH_INTERNAL(hash, HeKEY(entry), HeKLEN(entry));
1159 = save_hek_flags(HeKEY(entry), HeKLEN(entry),
1160 hash, HeKFLAGS(entry));
1161 unshare_hek (HeKEY_hek(entry));
1162 HeKEY_hek(entry) = new_hek;
1164 /* Not shared, so simply write the new hash in. */
1165 HeHASH(entry) = hash;
1167 /*PerlIO_printf(PerlIO_stderr(), "%d ", HeKFLAGS(entry));*/
1168 HEK_REHASH_on(HeKEY_hek(entry));
1169 /*PerlIO_printf(PerlIO_stderr(), "%d\n", HeKFLAGS(entry));*/
1171 /* Copy oentry to the correct new chain. */
1172 bep = ((HE**)a) + (hash & (I32) xhv->xhv_max);
1174 xhv->xhv_fill++; /* HvFILL(hv)++ */
1175 HeNEXT(entry) = *bep;
1181 Safefree (xhv->xhv_array);
1182 xhv->xhv_array = a; /* HvARRAY(hv) = a */
1186 Perl_hv_ksplit(pTHX_ HV *hv, IV newmax)
1188 register XPVHV* xhv = (XPVHV*)SvANY(hv);
1189 I32 oldsize = (I32) xhv->xhv_max+1; /* HvMAX(hv)+1 (sick) */
1190 register I32 newsize;
1196 register HE **oentry;
1198 newsize = (I32) newmax; /* possible truncation here */
1199 if (newsize != newmax || newmax <= oldsize)
1201 while ((newsize & (1 + ~newsize)) != newsize) {
1202 newsize &= ~(newsize & (1 + ~newsize)); /* get proper power of 2 */
1204 if (newsize < newmax)
1206 if (newsize < newmax)
1207 return; /* overflow detection */
1209 a = xhv->xhv_array; /* HvARRAY(hv) */
1212 #if defined(STRANGE_MALLOC) || defined(MYMALLOC)
1213 Renew(a, PERL_HV_ARRAY_ALLOC_BYTES(newsize), char);
1219 New(2, a, PERL_HV_ARRAY_ALLOC_BYTES(newsize), char);
1224 Copy(xhv->xhv_array /* HvARRAY(hv) */, a, oldsize * sizeof(HE*), char);
1225 if (oldsize >= 64) {
1226 offer_nice_chunk(xhv->xhv_array /* HvARRAY(hv) */,
1227 PERL_HV_ARRAY_ALLOC_BYTES(oldsize));
1230 Safefree(xhv->xhv_array /* HvARRAY(hv) */);
1233 Zero(&a[oldsize * sizeof(HE*)], (newsize-oldsize) * sizeof(HE*), char); /* zero 2nd half*/
1236 Newz(0, a, PERL_HV_ARRAY_ALLOC_BYTES(newsize), char);
1238 xhv->xhv_max = --newsize; /* HvMAX(hv) = --newsize */
1239 xhv->xhv_array = a; /* HvARRAY(hv) = a */
1240 if (!xhv->xhv_fill /* !HvFILL(hv) */) /* skip rest if no entries */
1244 for (i=0; i<oldsize; i++,aep++) {
1245 if (!*aep) /* non-existent */
1247 for (oentry = aep, entry = *aep; entry; entry = *oentry) {
1248 if ((j = (HeHASH(entry) & newsize)) != i) {
1250 *oentry = HeNEXT(entry);
1251 if (!(HeNEXT(entry) = aep[j]))
1252 xhv->xhv_fill++; /* HvFILL(hv)++ */
1257 oentry = &HeNEXT(entry);
1259 if (!*aep) /* everything moved */
1260 xhv->xhv_fill--; /* HvFILL(hv)-- */
1267 Creates a new HV. The reference count is set to 1.
1276 register XPVHV* xhv;
1278 hv = (HV*)NEWSV(502,0);
1279 sv_upgrade((SV *)hv, SVt_PVHV);
1280 xhv = (XPVHV*)SvANY(hv);
1283 #ifndef NODEFAULT_SHAREKEYS
1284 HvSHAREKEYS_on(hv); /* key-sharing on by default */
1287 xhv->xhv_max = 7; /* HvMAX(hv) = 7 (start with 8 buckets) */
1288 xhv->xhv_fill = 0; /* HvFILL(hv) = 0 */
1289 xhv->xhv_pmroot = 0; /* HvPMROOT(hv) = 0 */
1290 (void)hv_iterinit(hv); /* so each() will start off right */
1295 Perl_newHVhv(pTHX_ HV *ohv)
1298 STRLEN hv_max, hv_fill;
1300 if (!ohv || (hv_fill = HvFILL(ohv)) == 0)
1302 hv_max = HvMAX(ohv);
1304 if (!SvMAGICAL((SV *)ohv)) {
1305 /* It's an ordinary hash, so copy it fast. AMS 20010804 */
1307 bool shared = !!HvSHAREKEYS(ohv);
1308 HE **ents, **oents = (HE **)HvARRAY(ohv);
1310 New(0, a, PERL_HV_ARRAY_ALLOC_BYTES(hv_max+1), char);
1313 /* In each bucket... */
1314 for (i = 0; i <= hv_max; i++) {
1315 HE *prev = NULL, *ent = NULL, *oent = oents[i];
1322 /* Copy the linked list of entries. */
1323 for (oent = oents[i]; oent; oent = HeNEXT(oent)) {
1324 U32 hash = HeHASH(oent);
1325 char *key = HeKEY(oent);
1326 STRLEN len = HeKLEN(oent);
1327 int flags = HeKFLAGS(oent);
1330 HeVAL(ent) = newSVsv(HeVAL(oent));
1332 = shared ? share_hek_flags(key, len, hash, flags)
1333 : save_hek_flags(key, len, hash, flags);
1344 HvFILL(hv) = hv_fill;
1345 HvTOTALKEYS(hv) = HvTOTALKEYS(ohv);
1349 /* Iterate over ohv, copying keys and values one at a time. */
1351 I32 riter = HvRITER(ohv);
1352 HE *eiter = HvEITER(ohv);
1354 /* Can we use fewer buckets? (hv_max is always 2^n-1) */
1355 while (hv_max && hv_max + 1 >= hv_fill * 2)
1356 hv_max = hv_max / 2;
1360 while ((entry = hv_iternext_flags(ohv, 0))) {
1361 hv_store_flags(hv, HeKEY(entry), HeKLEN(entry),
1362 newSVsv(HeVAL(entry)), HeHASH(entry),
1365 HvRITER(ohv) = riter;
1366 HvEITER(ohv) = eiter;
1373 Perl_hv_free_ent(pTHX_ HV *hv, register HE *entry)
1380 if (val && isGV(val) && GvCVu(val) && HvNAME(hv))
1381 PL_sub_generation++; /* may be deletion of method from stash */
1383 if (HeKLEN(entry) == HEf_SVKEY) {
1384 SvREFCNT_dec(HeKEY_sv(entry));
1385 Safefree(HeKEY_hek(entry));
1387 else if (HvSHAREKEYS(hv))
1388 unshare_hek(HeKEY_hek(entry));
1390 Safefree(HeKEY_hek(entry));
1395 Perl_hv_delayfree_ent(pTHX_ HV *hv, register HE *entry)
1399 if (isGV(HeVAL(entry)) && GvCVu(HeVAL(entry)) && HvNAME(hv))
1400 PL_sub_generation++; /* may be deletion of method from stash */
1401 sv_2mortal(HeVAL(entry)); /* free between statements */
1402 if (HeKLEN(entry) == HEf_SVKEY) {
1403 sv_2mortal(HeKEY_sv(entry));
1404 Safefree(HeKEY_hek(entry));
1406 else if (HvSHAREKEYS(hv))
1407 unshare_hek(HeKEY_hek(entry));
1409 Safefree(HeKEY_hek(entry));
1414 =for apidoc hv_clear
1416 Clears a hash, making it empty.
1422 Perl_hv_clear(pTHX_ HV *hv)
1424 register XPVHV* xhv;
1428 DEBUG_A(Perl_hv_assert(aTHX_ hv));
1430 xhv = (XPVHV*)SvANY(hv);
1432 if (SvREADONLY(hv) && xhv->xhv_array != NULL) {
1433 /* restricted hash: convert all keys to placeholders */
1436 for (i = 0; i <= (I32) xhv->xhv_max; i++) {
1437 entry = ((HE**)xhv->xhv_array)[i];
1438 for (; entry; entry = HeNEXT(entry)) {
1439 /* not already placeholder */
1440 if (HeVAL(entry) != &PL_sv_placeholder) {
1441 if (HeVAL(entry) && SvREADONLY(HeVAL(entry))) {
1442 SV* keysv = hv_iterkeysv(entry);
1444 "Attempt to delete readonly key '%"SVf"' from a restricted hash",
1447 SvREFCNT_dec(HeVAL(entry));
1448 HeVAL(entry) = &PL_sv_placeholder;
1449 xhv->xhv_placeholders++; /* HvPLACEHOLDERS(hv)++ */
1457 xhv->xhv_placeholders = 0; /* HvPLACEHOLDERS(hv) = 0 */
1458 if (xhv->xhv_array /* HvARRAY(hv) */)
1459 (void)memzero(xhv->xhv_array /* HvARRAY(hv) */,
1460 (xhv->xhv_max+1 /* HvMAX(hv)+1 */) * sizeof(HE*));
1465 HvHASKFLAGS_off(hv);
1472 =for apidoc hv_clear_placeholders
1474 Clears any placeholders from a hash. If a restricted hash has any of its keys
1475 marked as readonly and the key is subsequently deleted, the key is not actually
1476 deleted but is marked by assigning it a value of &PL_sv_placeholder. This tags
1477 it so it will be ignored by future operations such as iterating over the hash,
1478 but will still allow the hash to have a value reaasigned to the key at some
1479 future point. This function clears any such placeholder keys from the hash.
1480 See Hash::Util::lock_keys() for an example of its use.
1486 Perl_hv_clear_placeholders(pTHX_ HV *hv)
1489 items = (I32)HvPLACEHOLDERS(hv);
1492 I32 riter = HvRITER(hv);
1493 HE *eiter = HvEITER(hv);
1495 /* This may look suboptimal with the items *after* the iternext, but
1496 it's quite deliberate. We only get here with items==0 if we've
1497 just deleted the last placeholder in the hash. If we've just done
1498 that then it means that the hash is in lazy delete mode, and the
1499 HE is now only referenced in our iterator. If we just quit the loop
1500 and discarded our iterator then the HE leaks. So we do the && the
1501 other way to ensure iternext is called just one more time, which
1502 has the side effect of triggering the lazy delete. */
1503 while ((entry = hv_iternext_flags(hv, HV_ITERNEXT_WANTPLACEHOLDERS))
1505 SV *val = hv_iterval(hv, entry);
1507 if (val == &PL_sv_placeholder) {
1509 /* It seems that I have to go back in the front of the hash
1510 API to delete a hash, even though I have a HE structure
1511 pointing to the very entry I want to delete, and could hold
1512 onto the previous HE that points to it. And it's easier to
1513 go in with SVs as I can then specify the precomputed hash,
1514 and don't have fun and games with utf8 keys. */
1515 SV *key = hv_iterkeysv(entry);
1517 hv_delete_ent (hv, key, G_DISCARD, HeHASH(entry));
1521 HvRITER(hv) = riter;
1522 HvEITER(hv) = eiter;
1527 S_hfreeentries(pTHX_ HV *hv)
1529 register HE **array;
1531 register HE *oentry = Null(HE*);
1542 array = HvARRAY(hv);
1543 /* make everyone else think the array is empty, so that the destructors
1544 * called for freed entries can't recusively mess with us */
1545 HvARRAY(hv) = Null(HE**);
1547 ((XPVHV*) SvANY(hv))->xhv_keys = 0;
1553 entry = HeNEXT(entry);
1554 hv_free_ent(hv, oentry);
1559 entry = array[riter];
1562 HvARRAY(hv) = array;
1563 (void)hv_iterinit(hv);
1567 =for apidoc hv_undef
1575 Perl_hv_undef(pTHX_ HV *hv)
1577 register XPVHV* xhv;
1580 DEBUG_A(Perl_hv_assert(aTHX_ hv));
1581 xhv = (XPVHV*)SvANY(hv);
1583 Safefree(xhv->xhv_array /* HvARRAY(hv) */);
1586 hv_delete(PL_stashcache, HvNAME(hv), strlen(HvNAME(hv)), G_DISCARD);
1587 Safefree(HvNAME(hv));
1590 xhv->xhv_max = 7; /* HvMAX(hv) = 7 (it's a normal hash) */
1591 xhv->xhv_array = 0; /* HvARRAY(hv) = 0 */
1592 xhv->xhv_placeholders = 0; /* HvPLACEHOLDERS(hv) = 0 */
1599 =for apidoc hv_iterinit
1601 Prepares a starting point to traverse a hash table. Returns the number of
1602 keys in the hash (i.e. the same as C<HvKEYS(tb)>). The return value is
1603 currently only meaningful for hashes without tie magic.
1605 NOTE: Before version 5.004_65, C<hv_iterinit> used to return the number of
1606 hash buckets that happen to be in use. If you still need that esoteric
1607 value, you can get it through the macro C<HvFILL(tb)>.
1614 Perl_hv_iterinit(pTHX_ HV *hv)
1616 register XPVHV* xhv;
1620 Perl_croak(aTHX_ "Bad hash");
1621 xhv = (XPVHV*)SvANY(hv);
1622 entry = xhv->xhv_eiter; /* HvEITER(hv) */
1623 if (entry && HvLAZYDEL(hv)) { /* was deleted earlier? */
1625 hv_free_ent(hv, entry);
1627 xhv->xhv_riter = -1; /* HvRITER(hv) = -1 */
1628 xhv->xhv_eiter = Null(HE*); /* HvEITER(hv) = Null(HE*) */
1629 /* used to be xhv->xhv_fill before 5.004_65 */
1630 return XHvTOTALKEYS(xhv);
1633 =for apidoc hv_iternext
1635 Returns entries from a hash iterator. See C<hv_iterinit>.
1637 You may call C<hv_delete> or C<hv_delete_ent> on the hash entry that the
1638 iterator currently points to, without losing your place or invalidating your
1639 iterator. Note that in this case the current entry is deleted from the hash
1640 with your iterator holding the last reference to it. Your iterator is flagged
1641 to free the entry on the next call to C<hv_iternext>, so you must not discard
1642 your iterator immediately else the entry will leak - call C<hv_iternext> to
1643 trigger the resource deallocation.
1649 Perl_hv_iternext(pTHX_ HV *hv)
1651 return hv_iternext_flags(hv, 0);
1655 =for apidoc hv_iternext_flags
1657 Returns entries from a hash iterator. See C<hv_iterinit> and C<hv_iternext>.
1658 The C<flags> value will normally be zero; if HV_ITERNEXT_WANTPLACEHOLDERS is
1659 set the placeholders keys (for restricted hashes) will be returned in addition
1660 to normal keys. By default placeholders are automatically skipped over.
1661 Currently a placeholder is implemented with a value that is
1662 C<&Perl_sv_placeholder>. Note that the implementation of placeholders and
1663 restricted hashes may change, and the implementation currently is
1664 insufficiently abstracted for any change to be tidy.
1670 Perl_hv_iternext_flags(pTHX_ HV *hv, I32 flags)
1672 register XPVHV* xhv;
1678 Perl_croak(aTHX_ "Bad hash");
1679 xhv = (XPVHV*)SvANY(hv);
1680 oldentry = entry = xhv->xhv_eiter; /* HvEITER(hv) */
1682 if ((mg = SvTIED_mg((SV*)hv, PERL_MAGIC_tied))) {
1683 SV *key = sv_newmortal();
1685 sv_setsv(key, HeSVKEY_force(entry));
1686 SvREFCNT_dec(HeSVKEY(entry)); /* get rid of previous key */
1692 /* one HE per MAGICAL hash */
1693 xhv->xhv_eiter = entry = new_HE(); /* HvEITER(hv) = new_HE() */
1695 Newz(54, k, HEK_BASESIZE + sizeof(SV*), char);
1697 HeKEY_hek(entry) = hek;
1698 HeKLEN(entry) = HEf_SVKEY;
1700 magic_nextpack((SV*) hv,mg,key);
1702 /* force key to stay around until next time */
1703 HeSVKEY_set(entry, SvREFCNT_inc(key));
1704 return entry; /* beware, hent_val is not set */
1707 SvREFCNT_dec(HeVAL(entry));
1708 Safefree(HeKEY_hek(entry));
1710 xhv->xhv_eiter = Null(HE*); /* HvEITER(hv) = Null(HE*) */
1713 #ifdef DYNAMIC_ENV_FETCH /* set up %ENV for iteration */
1714 if (!entry && SvRMAGICAL((SV*)hv) && mg_find((SV*)hv, PERL_MAGIC_env))
1718 if (!xhv->xhv_array /* !HvARRAY(hv) */)
1719 Newz(506, xhv->xhv_array /* HvARRAY(hv) */,
1720 PERL_HV_ARRAY_ALLOC_BYTES(xhv->xhv_max+1 /* HvMAX(hv)+1 */),
1722 /* At start of hash, entry is NULL. */
1725 entry = HeNEXT(entry);
1726 if (!(flags & HV_ITERNEXT_WANTPLACEHOLDERS)) {
1728 * Skip past any placeholders -- don't want to include them in
1731 while (entry && HeVAL(entry) == &PL_sv_placeholder) {
1732 entry = HeNEXT(entry);
1737 /* OK. Come to the end of the current list. Grab the next one. */
1739 xhv->xhv_riter++; /* HvRITER(hv)++ */
1740 if (xhv->xhv_riter > (I32)xhv->xhv_max /* HvRITER(hv) > HvMAX(hv) */) {
1741 /* There is no next one. End of the hash. */
1742 xhv->xhv_riter = -1; /* HvRITER(hv) = -1 */
1745 /* entry = (HvARRAY(hv))[HvRITER(hv)]; */
1746 entry = ((HE**)xhv->xhv_array)[xhv->xhv_riter];
1748 if (!(flags & HV_ITERNEXT_WANTPLACEHOLDERS)) {
1749 /* If we have an entry, but it's a placeholder, don't count it.
1751 while (entry && HeVAL(entry) == &PL_sv_placeholder)
1752 entry = HeNEXT(entry);
1754 /* Will loop again if this linked list starts NULL
1755 (for HV_ITERNEXT_WANTPLACEHOLDERS)
1756 or if we run through it and find only placeholders. */
1759 if (oldentry && HvLAZYDEL(hv)) { /* was deleted earlier? */
1761 hv_free_ent(hv, oldentry);
1764 /*if (HvREHASH(hv) && entry && !HeKREHASH(entry))
1765 PerlIO_printf(PerlIO_stderr(), "Awooga %p %p\n", hv, entry);*/
1767 xhv->xhv_eiter = entry; /* HvEITER(hv) = entry */
1772 =for apidoc hv_iterkey
1774 Returns the key from the current position of the hash iterator. See
1781 Perl_hv_iterkey(pTHX_ register HE *entry, I32 *retlen)
1783 if (HeKLEN(entry) == HEf_SVKEY) {
1785 char *p = SvPV(HeKEY_sv(entry), len);
1790 *retlen = HeKLEN(entry);
1791 return HeKEY(entry);
1795 /* unlike hv_iterval(), this always returns a mortal copy of the key */
1797 =for apidoc hv_iterkeysv
1799 Returns the key as an C<SV*> from the current position of the hash
1800 iterator. The return value will always be a mortal copy of the key. Also
1807 Perl_hv_iterkeysv(pTHX_ register HE *entry)
1809 if (HeKLEN(entry) != HEf_SVKEY) {
1810 HEK *hek = HeKEY_hek(entry);
1811 int flags = HEK_FLAGS(hek);
1814 if (flags & HVhek_WASUTF8) {
1816 Andreas would like keys he put in as utf8 to come back as utf8
1818 STRLEN utf8_len = HEK_LEN(hek);
1819 U8 *as_utf8 = bytes_to_utf8 ((U8*)HEK_KEY(hek), &utf8_len);
1821 sv = newSVpvn ((char*)as_utf8, utf8_len);
1823 Safefree (as_utf8); /* bytes_to_utf8() allocates a new string */
1824 } else if (flags & HVhek_REHASH) {
1825 /* We don't have a pointer to the hv, so we have to replicate the
1826 flag into every HEK. This hv is using custom a hasing
1827 algorithm. Hence we can't return a shared string scalar, as
1828 that would contain the (wrong) hash value, and might get passed
1829 into an hv routine with a regular hash */
1831 sv = newSVpvn (HEK_KEY(hek), HEK_LEN(hek));
1835 sv = newSVpvn_share(HEK_KEY(hek),
1836 (HEK_UTF8(hek) ? -HEK_LEN(hek) : HEK_LEN(hek)),
1839 return sv_2mortal(sv);
1841 return sv_mortalcopy(HeKEY_sv(entry));
1845 =for apidoc hv_iterval
1847 Returns the value from the current position of the hash iterator. See
1854 Perl_hv_iterval(pTHX_ HV *hv, register HE *entry)
1856 if (SvRMAGICAL(hv)) {
1857 if (mg_find((SV*)hv, PERL_MAGIC_tied)) {
1858 SV* sv = sv_newmortal();
1859 if (HeKLEN(entry) == HEf_SVKEY)
1860 mg_copy((SV*)hv, sv, (char*)HeKEY_sv(entry), HEf_SVKEY);
1861 else mg_copy((SV*)hv, sv, HeKEY(entry), HeKLEN(entry));
1865 return HeVAL(entry);
1869 =for apidoc hv_iternextsv
1871 Performs an C<hv_iternext>, C<hv_iterkey>, and C<hv_iterval> in one
1878 Perl_hv_iternextsv(pTHX_ HV *hv, char **key, I32 *retlen)
1881 if ( (he = hv_iternext_flags(hv, 0)) == NULL)
1883 *key = hv_iterkey(he, retlen);
1884 return hv_iterval(hv, he);
1888 =for apidoc hv_magic
1890 Adds magic to a hash. See C<sv_magic>.
1896 Perl_hv_magic(pTHX_ HV *hv, GV *gv, int how)
1898 sv_magic((SV*)hv, (SV*)gv, how, Nullch, 0);
1901 #if 0 /* use the macro from hv.h instead */
1904 Perl_sharepvn(pTHX_ const char *sv, I32 len, U32 hash)
1906 return HEK_KEY(share_hek(sv, len, hash));
1911 /* possibly free a shared string if no one has access to it
1912 * len and hash must both be valid for str.
1915 Perl_unsharepvn(pTHX_ const char *str, I32 len, U32 hash)
1917 unshare_hek_or_pvn (NULL, str, len, hash);
1922 Perl_unshare_hek(pTHX_ HEK *hek)
1924 unshare_hek_or_pvn(hek, NULL, 0, 0);
1927 /* possibly free a shared string if no one has access to it
1928 hek if non-NULL takes priority over the other 3, else str, len and hash
1929 are used. If so, len and hash must both be valid for str.
1932 S_unshare_hek_or_pvn(pTHX_ HEK *hek, const char *str, I32 len, U32 hash)
1934 register XPVHV* xhv;
1936 register HE **oentry;
1939 bool is_utf8 = FALSE;
1941 const char *save = str;
1944 hash = HEK_HASH(hek);
1945 } else if (len < 0) {
1946 STRLEN tmplen = -len;
1948 /* See the note in hv_fetch(). --jhi */
1949 str = (char*)bytes_from_utf8((U8*)str, &tmplen, &is_utf8);
1952 k_flags = HVhek_UTF8;
1954 k_flags |= HVhek_WASUTF8 | HVhek_FREEKEY;
1957 /* what follows is the moral equivalent of:
1958 if ((Svp = hv_fetch(PL_strtab, tmpsv, FALSE, hash))) {
1959 if (--*Svp == Nullsv)
1960 hv_delete(PL_strtab, str, len, G_DISCARD, hash);
1962 xhv = (XPVHV*)SvANY(PL_strtab);
1963 /* assert(xhv_array != 0) */
1965 /* oentry = &(HvARRAY(hv))[hash & (I32) HvMAX(hv)]; */
1966 oentry = &((HE**)xhv->xhv_array)[hash & (I32) xhv->xhv_max];
1968 for (entry = *oentry; entry; i=0, oentry = &HeNEXT(entry), entry = *oentry) {
1969 if (HeKEY_hek(entry) != hek)
1975 int flags_masked = k_flags & HVhek_MASK;
1976 for (entry = *oentry; entry; i=0, oentry = &HeNEXT(entry), entry = *oentry) {
1977 if (HeHASH(entry) != hash) /* strings can't be equal */
1979 if (HeKLEN(entry) != len)
1981 if (HeKEY(entry) != str && memNE(HeKEY(entry),str,len)) /* is this it? */
1983 if (HeKFLAGS(entry) != flags_masked)
1991 if (--HeVAL(entry) == Nullsv) {
1992 *oentry = HeNEXT(entry);
1994 xhv->xhv_fill--; /* HvFILL(hv)-- */
1995 Safefree(HeKEY_hek(entry));
1997 xhv->xhv_keys--; /* HvKEYS(hv)-- */
2001 UNLOCK_STRTAB_MUTEX;
2002 if (!found && ckWARN_d(WARN_INTERNAL))
2003 Perl_warner(aTHX_ packWARN(WARN_INTERNAL),
2004 "Attempt to free non-existent shared string '%s'%s",
2005 hek ? HEK_KEY(hek) : str,
2006 (k_flags & HVhek_UTF8) ? " (utf8)" : "");
2007 if (k_flags & HVhek_FREEKEY)
2011 /* get a (constant) string ptr from the global string table
2012 * string will get added if it is not already there.
2013 * len and hash must both be valid for str.
2016 Perl_share_hek(pTHX_ const char *str, I32 len, register U32 hash)
2018 bool is_utf8 = FALSE;
2020 const char *save = str;
2023 STRLEN tmplen = -len;
2025 /* See the note in hv_fetch(). --jhi */
2026 str = (char*)bytes_from_utf8((U8*)str, &tmplen, &is_utf8);
2028 /* If we were able to downgrade here, then than means that we were passed
2029 in a key which only had chars 0-255, but was utf8 encoded. */
2032 /* If we found we were able to downgrade the string to bytes, then
2033 we should flag that it needs upgrading on keys or each. Also flag
2034 that we need share_hek_flags to free the string. */
2036 flags |= HVhek_WASUTF8 | HVhek_FREEKEY;
2039 return share_hek_flags (str, len, hash, flags);
2043 S_share_hek_flags(pTHX_ const char *str, I32 len, register U32 hash, int flags)
2045 register XPVHV* xhv;
2047 register HE **oentry;
2050 int flags_masked = flags & HVhek_MASK;
2052 /* what follows is the moral equivalent of:
2054 if (!(Svp = hv_fetch(PL_strtab, str, len, FALSE)))
2055 hv_store(PL_strtab, str, len, Nullsv, hash);
2057 Can't rehash the shared string table, so not sure if it's worth
2058 counting the number of entries in the linked list
2060 xhv = (XPVHV*)SvANY(PL_strtab);
2061 /* assert(xhv_array != 0) */
2063 /* oentry = &(HvARRAY(hv))[hash & (I32) HvMAX(hv)]; */
2064 oentry = &((HE**)xhv->xhv_array)[hash & (I32) xhv->xhv_max];
2065 for (entry = *oentry; entry; i=0, entry = HeNEXT(entry)) {
2066 if (HeHASH(entry) != hash) /* strings can't be equal */
2068 if (HeKLEN(entry) != len)
2070 if (HeKEY(entry) != str && memNE(HeKEY(entry),str,len)) /* is this it? */
2072 if (HeKFLAGS(entry) != flags_masked)
2079 HeKEY_hek(entry) = save_hek_flags(str, len, hash, flags);
2080 HeVAL(entry) = Nullsv;
2081 HeNEXT(entry) = *oentry;
2083 xhv->xhv_keys++; /* HvKEYS(hv)++ */
2084 if (i) { /* initial entry? */
2085 xhv->xhv_fill++; /* HvFILL(hv)++ */
2086 } else if (xhv->xhv_keys > (IV)xhv->xhv_max /* HvKEYS(hv) > HvMAX(hv) */) {
2091 ++HeVAL(entry); /* use value slot as REFCNT */
2092 UNLOCK_STRTAB_MUTEX;
2094 if (flags & HVhek_FREEKEY)
2097 return HeKEY_hek(entry);
2102 =for apidoc hv_assert
2104 Check that a hash is in an internally consistent state.
2110 Perl_hv_assert(pTHX_ HV *hv)
2114 int placeholders = 0;
2117 I32 riter = HvRITER(hv);
2118 HE *eiter = HvEITER(hv);
2120 (void)hv_iterinit(hv);
2122 while ((entry = hv_iternext_flags(hv, HV_ITERNEXT_WANTPLACEHOLDERS))) {
2123 /* sanity check the values */
2124 if (HeVAL(entry) == &PL_sv_placeholder) {
2129 /* sanity check the keys */
2130 if (HeSVKEY(entry)) {
2131 /* Don't know what to check on SV keys. */
2132 } else if (HeKUTF8(entry)) {
2134 if (HeKWASUTF8(entry)) {
2135 PerlIO_printf(Perl_debug_log,
2136 "hash key has both WASUFT8 and UTF8: '%.*s'\n",
2137 (int) HeKLEN(entry), HeKEY(entry));
2140 } else if (HeKWASUTF8(entry)) {
2144 if (!SvTIED_mg((SV*)hv, PERL_MAGIC_tied)) {
2145 if (HvUSEDKEYS(hv) != real) {
2146 PerlIO_printf(Perl_debug_log, "Count %d key(s), but hash reports %d\n",
2147 (int) real, (int) HvUSEDKEYS(hv));
2150 if (HvPLACEHOLDERS(hv) != placeholders) {
2151 PerlIO_printf(Perl_debug_log,
2152 "Count %d placeholder(s), but hash reports %d\n",
2153 (int) placeholders, (int) HvPLACEHOLDERS(hv));
2157 if (withflags && ! HvHASKFLAGS(hv)) {
2158 PerlIO_printf(Perl_debug_log,
2159 "Hash has HASKFLAGS off but I count %d key(s) with flags\n",
2166 HvRITER(hv) = riter; /* Restore hash iterator state */
2167 HvEITER(hv) = eiter;