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 */
906 #ifdef ENV_IS_CASELESS
907 else if (mg_find((SV*)hv, PERL_MAGIC_env)) {
908 /* XXX This code isn't UTF8 clean. */
909 keysv = sv_2mortal(newSVpvn(key,klen));
910 key = strupr(SvPVX(keysv));
912 if (k_flags & HVhek_FREEKEY) {
923 xhv = (XPVHV*)SvANY(hv);
924 if (!xhv->xhv_array /* !HvARRAY(hv) */)
928 const char *keysave = key;
929 key = (char*)bytes_from_utf8((U8*)key, &klen, &is_utf8);
932 k_flags |= HVhek_UTF8;
934 k_flags &= ~HVhek_UTF8;
935 if (key != keysave) {
936 if (k_flags & HVhek_FREEKEY) {
937 /* This shouldn't happen if our caller does what we expect,
938 but strictly the API allows it. */
941 k_flags |= HVhek_WASUTF8 | HVhek_FREEKEY;
943 HvHASKFLAGS_on((SV*)hv);
947 PERL_HASH_INTERNAL(hash, key, klen);
949 if (keysv && (SvIsCOW_shared_hash(keysv))) {
952 PERL_HASH(hash, key, klen);
954 PERL_HASH(hash, key, klen);
957 masked_flags = (k_flags & HVhek_MASK);
959 /* oentry = &(HvARRAY(hv))[hash & (I32) HvMAX(hv)]; */
960 oentry = &((HE**)xhv->xhv_array)[hash & (I32) xhv->xhv_max];
963 for (; entry; i=0, oentry = &HeNEXT(entry), entry = *oentry) {
964 if (HeHASH(entry) != hash) /* strings can't be equal */
966 if (HeKLEN(entry) != (I32)klen)
968 if (HeKEY(entry) != key && memNE(HeKEY(entry),key,klen)) /* is this it? */
970 if ((HeKFLAGS(entry) ^ masked_flags) & HVhek_UTF8)
972 if (k_flags & HVhek_FREEKEY)
975 /* if placeholder is here, it's already been deleted.... */
976 if (HeVAL(entry) == &PL_sv_placeholder)
979 return Nullsv; /* if still SvREADONLY, leave it deleted. */
981 /* okay, really delete the placeholder. */
982 *oentry = HeNEXT(entry);
984 xhv->xhv_fill--; /* HvFILL(hv)-- */
985 if (entry == xhv->xhv_eiter /* HvEITER(hv) */)
988 hv_free_ent(hv, entry);
989 xhv->xhv_keys--; /* HvKEYS(hv)-- */
990 if (xhv->xhv_keys == 0)
992 xhv->xhv_placeholders--;
995 else if (SvREADONLY(hv) && HeVAL(entry) && SvREADONLY(HeVAL(entry))) {
996 S_hv_notallowed(aTHX_ k_flags, key, klen,
997 "delete readonly key '%"SVf"' from"
1001 if (d_flags & G_DISCARD)
1004 sv = sv_2mortal(HeVAL(entry));
1005 HeVAL(entry) = &PL_sv_placeholder;
1009 * If a restricted hash, rather than really deleting the entry, put
1010 * a placeholder there. This marks the key as being "approved", so
1011 * we can still access via not-really-existing key without raising
1014 if (SvREADONLY(hv)) {
1015 HeVAL(entry) = &PL_sv_placeholder;
1016 /* We'll be saving this slot, so the number of allocated keys
1017 * doesn't go down, but the number placeholders goes up */
1018 xhv->xhv_placeholders++; /* HvPLACEHOLDERS(hv)++ */
1020 *oentry = HeNEXT(entry);
1022 xhv->xhv_fill--; /* HvFILL(hv)-- */
1023 if (entry == xhv->xhv_eiter /* HvEITER(hv) */)
1026 hv_free_ent(hv, entry);
1027 xhv->xhv_keys--; /* HvKEYS(hv)-- */
1028 if (xhv->xhv_keys == 0)
1029 HvHASKFLAGS_off(hv);
1033 if (SvREADONLY(hv)) {
1034 S_hv_notallowed(aTHX_ k_flags, key, klen,
1035 "delete disallowed key '%"SVf"' from"
1039 if (k_flags & HVhek_FREEKEY)
1045 S_hsplit(pTHX_ HV *hv)
1047 register XPVHV* xhv = (XPVHV*)SvANY(hv);
1048 I32 oldsize = (I32) xhv->xhv_max+1; /* HvMAX(hv)+1 (sick) */
1049 register I32 newsize = oldsize * 2;
1051 register char *a = xhv->xhv_array; /* HvARRAY(hv) */
1055 register HE **oentry;
1056 int longest_chain = 0;
1060 #if defined(STRANGE_MALLOC) || defined(MYMALLOC)
1061 Renew(a, PERL_HV_ARRAY_ALLOC_BYTES(newsize), char);
1067 New(2, a, PERL_HV_ARRAY_ALLOC_BYTES(newsize), char);
1072 Copy(xhv->xhv_array /* HvARRAY(hv) */, a, oldsize * sizeof(HE*), char);
1073 if (oldsize >= 64) {
1074 offer_nice_chunk(xhv->xhv_array /* HvARRAY(hv) */,
1075 PERL_HV_ARRAY_ALLOC_BYTES(oldsize));
1078 Safefree(xhv->xhv_array /* HvARRAY(hv) */);
1082 Zero(&a[oldsize * sizeof(HE*)], (newsize-oldsize) * sizeof(HE*), char); /* zero 2nd half*/
1083 xhv->xhv_max = --newsize; /* HvMAX(hv) = --newsize */
1084 xhv->xhv_array = a; /* HvARRAY(hv) = a */
1087 for (i=0; i<oldsize; i++,aep++) {
1088 int left_length = 0;
1089 int right_length = 0;
1091 if (!*aep) /* non-existent */
1094 for (oentry = aep, entry = *aep; entry; entry = *oentry) {
1095 if ((HeHASH(entry) & newsize) != (U32)i) {
1096 *oentry = HeNEXT(entry);
1097 HeNEXT(entry) = *bep;
1099 xhv->xhv_fill++; /* HvFILL(hv)++ */
1105 oentry = &HeNEXT(entry);
1109 if (!*aep) /* everything moved */
1110 xhv->xhv_fill--; /* HvFILL(hv)-- */
1111 /* I think we don't actually need to keep track of the longest length,
1112 merely flag if anything is too long. But for the moment while
1113 developing this code I'll track it. */
1114 if (left_length > longest_chain)
1115 longest_chain = left_length;
1116 if (right_length > longest_chain)
1117 longest_chain = right_length;
1121 /* Pick your policy for "hashing isn't working" here: */
1122 if (longest_chain <= HV_MAX_LENGTH_BEFORE_SPLIT /* split worked? */
1127 if (hv == PL_strtab) {
1128 /* Urg. Someone is doing something nasty to the string table.
1133 /* Awooga. Awooga. Pathological data. */
1134 /*PerlIO_printf(PerlIO_stderr(), "%p %d of %d with %d/%d buckets\n", hv,
1135 longest_chain, HvTOTALKEYS(hv), HvFILL(hv), 1+HvMAX(hv));*/
1138 Newz(2, a, PERL_HV_ARRAY_ALLOC_BYTES(newsize), char);
1139 was_shared = HvSHAREKEYS(hv);
1142 HvSHAREKEYS_off(hv);
1145 aep = (HE **) xhv->xhv_array;
1147 for (i=0; i<newsize; i++,aep++) {
1150 /* We're going to trash this HE's next pointer when we chain it
1151 into the new hash below, so store where we go next. */
1152 HE *next = HeNEXT(entry);
1156 PERL_HASH_INTERNAL(hash, HeKEY(entry), HeKLEN(entry));
1161 = save_hek_flags(HeKEY(entry), HeKLEN(entry),
1162 hash, HeKFLAGS(entry));
1163 unshare_hek (HeKEY_hek(entry));
1164 HeKEY_hek(entry) = new_hek;
1166 /* Not shared, so simply write the new hash in. */
1167 HeHASH(entry) = hash;
1169 /*PerlIO_printf(PerlIO_stderr(), "%d ", HeKFLAGS(entry));*/
1170 HEK_REHASH_on(HeKEY_hek(entry));
1171 /*PerlIO_printf(PerlIO_stderr(), "%d\n", HeKFLAGS(entry));*/
1173 /* Copy oentry to the correct new chain. */
1174 bep = ((HE**)a) + (hash & (I32) xhv->xhv_max);
1176 xhv->xhv_fill++; /* HvFILL(hv)++ */
1177 HeNEXT(entry) = *bep;
1183 Safefree (xhv->xhv_array);
1184 xhv->xhv_array = a; /* HvARRAY(hv) = a */
1188 Perl_hv_ksplit(pTHX_ HV *hv, IV newmax)
1190 register XPVHV* xhv = (XPVHV*)SvANY(hv);
1191 I32 oldsize = (I32) xhv->xhv_max+1; /* HvMAX(hv)+1 (sick) */
1192 register I32 newsize;
1198 register HE **oentry;
1200 newsize = (I32) newmax; /* possible truncation here */
1201 if (newsize != newmax || newmax <= oldsize)
1203 while ((newsize & (1 + ~newsize)) != newsize) {
1204 newsize &= ~(newsize & (1 + ~newsize)); /* get proper power of 2 */
1206 if (newsize < newmax)
1208 if (newsize < newmax)
1209 return; /* overflow detection */
1211 a = xhv->xhv_array; /* HvARRAY(hv) */
1214 #if defined(STRANGE_MALLOC) || defined(MYMALLOC)
1215 Renew(a, PERL_HV_ARRAY_ALLOC_BYTES(newsize), char);
1221 New(2, a, PERL_HV_ARRAY_ALLOC_BYTES(newsize), char);
1226 Copy(xhv->xhv_array /* HvARRAY(hv) */, a, oldsize * sizeof(HE*), char);
1227 if (oldsize >= 64) {
1228 offer_nice_chunk(xhv->xhv_array /* HvARRAY(hv) */,
1229 PERL_HV_ARRAY_ALLOC_BYTES(oldsize));
1232 Safefree(xhv->xhv_array /* HvARRAY(hv) */);
1235 Zero(&a[oldsize * sizeof(HE*)], (newsize-oldsize) * sizeof(HE*), char); /* zero 2nd half*/
1238 Newz(0, a, PERL_HV_ARRAY_ALLOC_BYTES(newsize), char);
1240 xhv->xhv_max = --newsize; /* HvMAX(hv) = --newsize */
1241 xhv->xhv_array = a; /* HvARRAY(hv) = a */
1242 if (!xhv->xhv_fill /* !HvFILL(hv) */) /* skip rest if no entries */
1246 for (i=0; i<oldsize; i++,aep++) {
1247 if (!*aep) /* non-existent */
1249 for (oentry = aep, entry = *aep; entry; entry = *oentry) {
1250 if ((j = (HeHASH(entry) & newsize)) != i) {
1252 *oentry = HeNEXT(entry);
1253 if (!(HeNEXT(entry) = aep[j]))
1254 xhv->xhv_fill++; /* HvFILL(hv)++ */
1259 oentry = &HeNEXT(entry);
1261 if (!*aep) /* everything moved */
1262 xhv->xhv_fill--; /* HvFILL(hv)-- */
1269 Creates a new HV. The reference count is set to 1.
1278 register XPVHV* xhv;
1280 hv = (HV*)NEWSV(502,0);
1281 sv_upgrade((SV *)hv, SVt_PVHV);
1282 xhv = (XPVHV*)SvANY(hv);
1285 #ifndef NODEFAULT_SHAREKEYS
1286 HvSHAREKEYS_on(hv); /* key-sharing on by default */
1289 xhv->xhv_max = 7; /* HvMAX(hv) = 7 (start with 8 buckets) */
1290 xhv->xhv_fill = 0; /* HvFILL(hv) = 0 */
1291 xhv->xhv_pmroot = 0; /* HvPMROOT(hv) = 0 */
1292 (void)hv_iterinit(hv); /* so each() will start off right */
1297 Perl_newHVhv(pTHX_ HV *ohv)
1300 STRLEN hv_max, hv_fill;
1302 if (!ohv || (hv_fill = HvFILL(ohv)) == 0)
1304 hv_max = HvMAX(ohv);
1306 if (!SvMAGICAL((SV *)ohv)) {
1307 /* It's an ordinary hash, so copy it fast. AMS 20010804 */
1309 bool shared = !!HvSHAREKEYS(ohv);
1310 HE **ents, **oents = (HE **)HvARRAY(ohv);
1312 New(0, a, PERL_HV_ARRAY_ALLOC_BYTES(hv_max+1), char);
1315 /* In each bucket... */
1316 for (i = 0; i <= hv_max; i++) {
1317 HE *prev = NULL, *ent = NULL, *oent = oents[i];
1324 /* Copy the linked list of entries. */
1325 for (oent = oents[i]; oent; oent = HeNEXT(oent)) {
1326 U32 hash = HeHASH(oent);
1327 char *key = HeKEY(oent);
1328 STRLEN len = HeKLEN(oent);
1329 int flags = HeKFLAGS(oent);
1332 HeVAL(ent) = newSVsv(HeVAL(oent));
1334 = shared ? share_hek_flags(key, len, hash, flags)
1335 : save_hek_flags(key, len, hash, flags);
1346 HvFILL(hv) = hv_fill;
1347 HvTOTALKEYS(hv) = HvTOTALKEYS(ohv);
1351 /* Iterate over ohv, copying keys and values one at a time. */
1353 I32 riter = HvRITER(ohv);
1354 HE *eiter = HvEITER(ohv);
1356 /* Can we use fewer buckets? (hv_max is always 2^n-1) */
1357 while (hv_max && hv_max + 1 >= hv_fill * 2)
1358 hv_max = hv_max / 2;
1362 while ((entry = hv_iternext_flags(ohv, 0))) {
1363 hv_store_flags(hv, HeKEY(entry), HeKLEN(entry),
1364 newSVsv(HeVAL(entry)), HeHASH(entry),
1367 HvRITER(ohv) = riter;
1368 HvEITER(ohv) = eiter;
1375 Perl_hv_free_ent(pTHX_ HV *hv, register HE *entry)
1382 if (val && isGV(val) && GvCVu(val) && HvNAME(hv))
1383 PL_sub_generation++; /* may be deletion of method from stash */
1385 if (HeKLEN(entry) == HEf_SVKEY) {
1386 SvREFCNT_dec(HeKEY_sv(entry));
1387 Safefree(HeKEY_hek(entry));
1389 else if (HvSHAREKEYS(hv))
1390 unshare_hek(HeKEY_hek(entry));
1392 Safefree(HeKEY_hek(entry));
1397 Perl_hv_delayfree_ent(pTHX_ HV *hv, register HE *entry)
1401 if (isGV(HeVAL(entry)) && GvCVu(HeVAL(entry)) && HvNAME(hv))
1402 PL_sub_generation++; /* may be deletion of method from stash */
1403 sv_2mortal(HeVAL(entry)); /* free between statements */
1404 if (HeKLEN(entry) == HEf_SVKEY) {
1405 sv_2mortal(HeKEY_sv(entry));
1406 Safefree(HeKEY_hek(entry));
1408 else if (HvSHAREKEYS(hv))
1409 unshare_hek(HeKEY_hek(entry));
1411 Safefree(HeKEY_hek(entry));
1416 =for apidoc hv_clear
1418 Clears a hash, making it empty.
1424 Perl_hv_clear(pTHX_ HV *hv)
1426 register XPVHV* xhv;
1430 DEBUG_A(Perl_hv_assert(aTHX_ hv));
1432 xhv = (XPVHV*)SvANY(hv);
1434 if (SvREADONLY(hv) && xhv->xhv_array != NULL) {
1435 /* restricted hash: convert all keys to placeholders */
1438 for (i = 0; i <= (I32) xhv->xhv_max; i++) {
1439 entry = ((HE**)xhv->xhv_array)[i];
1440 for (; entry; entry = HeNEXT(entry)) {
1441 /* not already placeholder */
1442 if (HeVAL(entry) != &PL_sv_placeholder) {
1443 if (HeVAL(entry) && SvREADONLY(HeVAL(entry))) {
1444 SV* keysv = hv_iterkeysv(entry);
1446 "Attempt to delete readonly key '%"SVf"' from a restricted hash",
1449 SvREFCNT_dec(HeVAL(entry));
1450 HeVAL(entry) = &PL_sv_placeholder;
1451 xhv->xhv_placeholders++; /* HvPLACEHOLDERS(hv)++ */
1459 xhv->xhv_placeholders = 0; /* HvPLACEHOLDERS(hv) = 0 */
1460 if (xhv->xhv_array /* HvARRAY(hv) */)
1461 (void)memzero(xhv->xhv_array /* HvARRAY(hv) */,
1462 (xhv->xhv_max+1 /* HvMAX(hv)+1 */) * sizeof(HE*));
1467 HvHASKFLAGS_off(hv);
1474 =for apidoc hv_clear_placeholders
1476 Clears any placeholders from a hash. If a restricted hash has any of its keys
1477 marked as readonly and the key is subsequently deleted, the key is not actually
1478 deleted but is marked by assigning it a value of &PL_sv_placeholder. This tags
1479 it so it will be ignored by future operations such as iterating over the hash,
1480 but will still allow the hash to have a value reaasigned to the key at some
1481 future point. This function clears any such placeholder keys from the hash.
1482 See Hash::Util::lock_keys() for an example of its use.
1488 Perl_hv_clear_placeholders(pTHX_ HV *hv)
1491 items = (I32)HvPLACEHOLDERS(hv);
1494 I32 riter = HvRITER(hv);
1495 HE *eiter = HvEITER(hv);
1497 /* This may look suboptimal with the items *after* the iternext, but
1498 it's quite deliberate. We only get here with items==0 if we've
1499 just deleted the last placeholder in the hash. If we've just done
1500 that then it means that the hash is in lazy delete mode, and the
1501 HE is now only referenced in our iterator. If we just quit the loop
1502 and discarded our iterator then the HE leaks. So we do the && the
1503 other way to ensure iternext is called just one more time, which
1504 has the side effect of triggering the lazy delete. */
1505 while ((entry = hv_iternext_flags(hv, HV_ITERNEXT_WANTPLACEHOLDERS))
1507 SV *val = hv_iterval(hv, entry);
1509 if (val == &PL_sv_placeholder) {
1511 /* It seems that I have to go back in the front of the hash
1512 API to delete a hash, even though I have a HE structure
1513 pointing to the very entry I want to delete, and could hold
1514 onto the previous HE that points to it. And it's easier to
1515 go in with SVs as I can then specify the precomputed hash,
1516 and don't have fun and games with utf8 keys. */
1517 SV *key = hv_iterkeysv(entry);
1519 hv_delete_ent (hv, key, G_DISCARD, HeHASH(entry));
1523 HvRITER(hv) = riter;
1524 HvEITER(hv) = eiter;
1529 S_hfreeentries(pTHX_ HV *hv)
1531 register HE **array;
1533 register HE *oentry = Null(HE*);
1544 array = HvARRAY(hv);
1545 /* make everyone else think the array is empty, so that the destructors
1546 * called for freed entries can't recusively mess with us */
1547 HvARRAY(hv) = Null(HE**);
1549 ((XPVHV*) SvANY(hv))->xhv_keys = 0;
1555 entry = HeNEXT(entry);
1556 hv_free_ent(hv, oentry);
1561 entry = array[riter];
1564 HvARRAY(hv) = array;
1565 (void)hv_iterinit(hv);
1569 =for apidoc hv_undef
1577 Perl_hv_undef(pTHX_ HV *hv)
1579 register XPVHV* xhv;
1582 DEBUG_A(Perl_hv_assert(aTHX_ hv));
1583 xhv = (XPVHV*)SvANY(hv);
1585 Safefree(xhv->xhv_array /* HvARRAY(hv) */);
1588 hv_delete(PL_stashcache, HvNAME(hv), strlen(HvNAME(hv)), G_DISCARD);
1589 Safefree(HvNAME(hv));
1592 xhv->xhv_max = 7; /* HvMAX(hv) = 7 (it's a normal hash) */
1593 xhv->xhv_array = 0; /* HvARRAY(hv) = 0 */
1594 xhv->xhv_placeholders = 0; /* HvPLACEHOLDERS(hv) = 0 */
1601 =for apidoc hv_iterinit
1603 Prepares a starting point to traverse a hash table. Returns the number of
1604 keys in the hash (i.e. the same as C<HvKEYS(tb)>). The return value is
1605 currently only meaningful for hashes without tie magic.
1607 NOTE: Before version 5.004_65, C<hv_iterinit> used to return the number of
1608 hash buckets that happen to be in use. If you still need that esoteric
1609 value, you can get it through the macro C<HvFILL(tb)>.
1616 Perl_hv_iterinit(pTHX_ HV *hv)
1618 register XPVHV* xhv;
1622 Perl_croak(aTHX_ "Bad hash");
1623 xhv = (XPVHV*)SvANY(hv);
1624 entry = xhv->xhv_eiter; /* HvEITER(hv) */
1625 if (entry && HvLAZYDEL(hv)) { /* was deleted earlier? */
1627 hv_free_ent(hv, entry);
1629 xhv->xhv_riter = -1; /* HvRITER(hv) = -1 */
1630 xhv->xhv_eiter = Null(HE*); /* HvEITER(hv) = Null(HE*) */
1631 /* used to be xhv->xhv_fill before 5.004_65 */
1632 return XHvTOTALKEYS(xhv);
1635 =for apidoc hv_iternext
1637 Returns entries from a hash iterator. See C<hv_iterinit>.
1639 You may call C<hv_delete> or C<hv_delete_ent> on the hash entry that the
1640 iterator currently points to, without losing your place or invalidating your
1641 iterator. Note that in this case the current entry is deleted from the hash
1642 with your iterator holding the last reference to it. Your iterator is flagged
1643 to free the entry on the next call to C<hv_iternext>, so you must not discard
1644 your iterator immediately else the entry will leak - call C<hv_iternext> to
1645 trigger the resource deallocation.
1651 Perl_hv_iternext(pTHX_ HV *hv)
1653 return hv_iternext_flags(hv, 0);
1657 =for apidoc hv_iternext_flags
1659 Returns entries from a hash iterator. See C<hv_iterinit> and C<hv_iternext>.
1660 The C<flags> value will normally be zero; if HV_ITERNEXT_WANTPLACEHOLDERS is
1661 set the placeholders keys (for restricted hashes) will be returned in addition
1662 to normal keys. By default placeholders are automatically skipped over.
1663 Currently a placeholder is implemented with a value that is
1664 C<&Perl_sv_placeholder>. Note that the implementation of placeholders and
1665 restricted hashes may change, and the implementation currently is
1666 insufficiently abstracted for any change to be tidy.
1672 Perl_hv_iternext_flags(pTHX_ HV *hv, I32 flags)
1674 register XPVHV* xhv;
1680 Perl_croak(aTHX_ "Bad hash");
1681 xhv = (XPVHV*)SvANY(hv);
1682 oldentry = entry = xhv->xhv_eiter; /* HvEITER(hv) */
1684 if ((mg = SvTIED_mg((SV*)hv, PERL_MAGIC_tied))) {
1685 SV *key = sv_newmortal();
1687 sv_setsv(key, HeSVKEY_force(entry));
1688 SvREFCNT_dec(HeSVKEY(entry)); /* get rid of previous key */
1694 /* one HE per MAGICAL hash */
1695 xhv->xhv_eiter = entry = new_HE(); /* HvEITER(hv) = new_HE() */
1697 Newz(54, k, HEK_BASESIZE + sizeof(SV*), char);
1699 HeKEY_hek(entry) = hek;
1700 HeKLEN(entry) = HEf_SVKEY;
1702 magic_nextpack((SV*) hv,mg,key);
1704 /* force key to stay around until next time */
1705 HeSVKEY_set(entry, SvREFCNT_inc(key));
1706 return entry; /* beware, hent_val is not set */
1709 SvREFCNT_dec(HeVAL(entry));
1710 Safefree(HeKEY_hek(entry));
1712 xhv->xhv_eiter = Null(HE*); /* HvEITER(hv) = Null(HE*) */
1715 #ifdef DYNAMIC_ENV_FETCH /* set up %ENV for iteration */
1716 if (!entry && SvRMAGICAL((SV*)hv) && mg_find((SV*)hv, PERL_MAGIC_env))
1720 if (!xhv->xhv_array /* !HvARRAY(hv) */)
1721 Newz(506, xhv->xhv_array /* HvARRAY(hv) */,
1722 PERL_HV_ARRAY_ALLOC_BYTES(xhv->xhv_max+1 /* HvMAX(hv)+1 */),
1724 /* At start of hash, entry is NULL. */
1727 entry = HeNEXT(entry);
1728 if (!(flags & HV_ITERNEXT_WANTPLACEHOLDERS)) {
1730 * Skip past any placeholders -- don't want to include them in
1733 while (entry && HeVAL(entry) == &PL_sv_placeholder) {
1734 entry = HeNEXT(entry);
1739 /* OK. Come to the end of the current list. Grab the next one. */
1741 xhv->xhv_riter++; /* HvRITER(hv)++ */
1742 if (xhv->xhv_riter > (I32)xhv->xhv_max /* HvRITER(hv) > HvMAX(hv) */) {
1743 /* There is no next one. End of the hash. */
1744 xhv->xhv_riter = -1; /* HvRITER(hv) = -1 */
1747 /* entry = (HvARRAY(hv))[HvRITER(hv)]; */
1748 entry = ((HE**)xhv->xhv_array)[xhv->xhv_riter];
1750 if (!(flags & HV_ITERNEXT_WANTPLACEHOLDERS)) {
1751 /* If we have an entry, but it's a placeholder, don't count it.
1753 while (entry && HeVAL(entry) == &PL_sv_placeholder)
1754 entry = HeNEXT(entry);
1756 /* Will loop again if this linked list starts NULL
1757 (for HV_ITERNEXT_WANTPLACEHOLDERS)
1758 or if we run through it and find only placeholders. */
1761 if (oldentry && HvLAZYDEL(hv)) { /* was deleted earlier? */
1763 hv_free_ent(hv, oldentry);
1766 /*if (HvREHASH(hv) && entry && !HeKREHASH(entry))
1767 PerlIO_printf(PerlIO_stderr(), "Awooga %p %p\n", hv, entry);*/
1769 xhv->xhv_eiter = entry; /* HvEITER(hv) = entry */
1774 =for apidoc hv_iterkey
1776 Returns the key from the current position of the hash iterator. See
1783 Perl_hv_iterkey(pTHX_ register HE *entry, I32 *retlen)
1785 if (HeKLEN(entry) == HEf_SVKEY) {
1787 char *p = SvPV(HeKEY_sv(entry), len);
1792 *retlen = HeKLEN(entry);
1793 return HeKEY(entry);
1797 /* unlike hv_iterval(), this always returns a mortal copy of the key */
1799 =for apidoc hv_iterkeysv
1801 Returns the key as an C<SV*> from the current position of the hash
1802 iterator. The return value will always be a mortal copy of the key. Also
1809 Perl_hv_iterkeysv(pTHX_ register HE *entry)
1811 if (HeKLEN(entry) != HEf_SVKEY) {
1812 HEK *hek = HeKEY_hek(entry);
1813 int flags = HEK_FLAGS(hek);
1816 if (flags & HVhek_WASUTF8) {
1818 Andreas would like keys he put in as utf8 to come back as utf8
1820 STRLEN utf8_len = HEK_LEN(hek);
1821 U8 *as_utf8 = bytes_to_utf8 ((U8*)HEK_KEY(hek), &utf8_len);
1823 sv = newSVpvn ((char*)as_utf8, utf8_len);
1825 Safefree (as_utf8); /* bytes_to_utf8() allocates a new string */
1826 } else if (flags & HVhek_REHASH) {
1827 /* We don't have a pointer to the hv, so we have to replicate the
1828 flag into every HEK. This hv is using custom a hasing
1829 algorithm. Hence we can't return a shared string scalar, as
1830 that would contain the (wrong) hash value, and might get passed
1831 into an hv routine with a regular hash */
1833 sv = newSVpvn (HEK_KEY(hek), HEK_LEN(hek));
1837 sv = newSVpvn_share(HEK_KEY(hek),
1838 (HEK_UTF8(hek) ? -HEK_LEN(hek) : HEK_LEN(hek)),
1841 return sv_2mortal(sv);
1843 return sv_mortalcopy(HeKEY_sv(entry));
1847 =for apidoc hv_iterval
1849 Returns the value from the current position of the hash iterator. See
1856 Perl_hv_iterval(pTHX_ HV *hv, register HE *entry)
1858 if (SvRMAGICAL(hv)) {
1859 if (mg_find((SV*)hv, PERL_MAGIC_tied)) {
1860 SV* sv = sv_newmortal();
1861 if (HeKLEN(entry) == HEf_SVKEY)
1862 mg_copy((SV*)hv, sv, (char*)HeKEY_sv(entry), HEf_SVKEY);
1863 else mg_copy((SV*)hv, sv, HeKEY(entry), HeKLEN(entry));
1867 return HeVAL(entry);
1871 =for apidoc hv_iternextsv
1873 Performs an C<hv_iternext>, C<hv_iterkey>, and C<hv_iterval> in one
1880 Perl_hv_iternextsv(pTHX_ HV *hv, char **key, I32 *retlen)
1883 if ( (he = hv_iternext_flags(hv, 0)) == NULL)
1885 *key = hv_iterkey(he, retlen);
1886 return hv_iterval(hv, he);
1890 =for apidoc hv_magic
1892 Adds magic to a hash. See C<sv_magic>.
1898 Perl_hv_magic(pTHX_ HV *hv, GV *gv, int how)
1900 sv_magic((SV*)hv, (SV*)gv, how, Nullch, 0);
1903 #if 0 /* use the macro from hv.h instead */
1906 Perl_sharepvn(pTHX_ const char *sv, I32 len, U32 hash)
1908 return HEK_KEY(share_hek(sv, len, hash));
1913 /* possibly free a shared string if no one has access to it
1914 * len and hash must both be valid for str.
1917 Perl_unsharepvn(pTHX_ const char *str, I32 len, U32 hash)
1919 unshare_hek_or_pvn (NULL, str, len, hash);
1924 Perl_unshare_hek(pTHX_ HEK *hek)
1926 unshare_hek_or_pvn(hek, NULL, 0, 0);
1929 /* possibly free a shared string if no one has access to it
1930 hek if non-NULL takes priority over the other 3, else str, len and hash
1931 are used. If so, len and hash must both be valid for str.
1934 S_unshare_hek_or_pvn(pTHX_ HEK *hek, const char *str, I32 len, U32 hash)
1936 register XPVHV* xhv;
1938 register HE **oentry;
1941 bool is_utf8 = FALSE;
1943 const char *save = str;
1946 hash = HEK_HASH(hek);
1947 } else if (len < 0) {
1948 STRLEN tmplen = -len;
1950 /* See the note in hv_fetch(). --jhi */
1951 str = (char*)bytes_from_utf8((U8*)str, &tmplen, &is_utf8);
1954 k_flags = HVhek_UTF8;
1956 k_flags |= HVhek_WASUTF8 | HVhek_FREEKEY;
1959 /* what follows is the moral equivalent of:
1960 if ((Svp = hv_fetch(PL_strtab, tmpsv, FALSE, hash))) {
1961 if (--*Svp == Nullsv)
1962 hv_delete(PL_strtab, str, len, G_DISCARD, hash);
1964 xhv = (XPVHV*)SvANY(PL_strtab);
1965 /* assert(xhv_array != 0) */
1967 /* oentry = &(HvARRAY(hv))[hash & (I32) HvMAX(hv)]; */
1968 oentry = &((HE**)xhv->xhv_array)[hash & (I32) xhv->xhv_max];
1970 for (entry = *oentry; entry; i=0, oentry = &HeNEXT(entry), entry = *oentry) {
1971 if (HeKEY_hek(entry) != hek)
1977 int flags_masked = k_flags & HVhek_MASK;
1978 for (entry = *oentry; entry; i=0, oentry = &HeNEXT(entry), entry = *oentry) {
1979 if (HeHASH(entry) != hash) /* strings can't be equal */
1981 if (HeKLEN(entry) != len)
1983 if (HeKEY(entry) != str && memNE(HeKEY(entry),str,len)) /* is this it? */
1985 if (HeKFLAGS(entry) != flags_masked)
1993 if (--HeVAL(entry) == Nullsv) {
1994 *oentry = HeNEXT(entry);
1996 xhv->xhv_fill--; /* HvFILL(hv)-- */
1997 Safefree(HeKEY_hek(entry));
1999 xhv->xhv_keys--; /* HvKEYS(hv)-- */
2003 UNLOCK_STRTAB_MUTEX;
2004 if (!found && ckWARN_d(WARN_INTERNAL))
2005 Perl_warner(aTHX_ packWARN(WARN_INTERNAL),
2006 "Attempt to free non-existent shared string '%s'%s",
2007 hek ? HEK_KEY(hek) : str,
2008 (k_flags & HVhek_UTF8) ? " (utf8)" : "");
2009 if (k_flags & HVhek_FREEKEY)
2013 /* get a (constant) string ptr from the global string table
2014 * string will get added if it is not already there.
2015 * len and hash must both be valid for str.
2018 Perl_share_hek(pTHX_ const char *str, I32 len, register U32 hash)
2020 bool is_utf8 = FALSE;
2022 const char *save = str;
2025 STRLEN tmplen = -len;
2027 /* See the note in hv_fetch(). --jhi */
2028 str = (char*)bytes_from_utf8((U8*)str, &tmplen, &is_utf8);
2030 /* If we were able to downgrade here, then than means that we were passed
2031 in a key which only had chars 0-255, but was utf8 encoded. */
2034 /* If we found we were able to downgrade the string to bytes, then
2035 we should flag that it needs upgrading on keys or each. Also flag
2036 that we need share_hek_flags to free the string. */
2038 flags |= HVhek_WASUTF8 | HVhek_FREEKEY;
2041 return share_hek_flags (str, len, hash, flags);
2045 S_share_hek_flags(pTHX_ const char *str, I32 len, register U32 hash, int flags)
2047 register XPVHV* xhv;
2049 register HE **oentry;
2052 int flags_masked = flags & HVhek_MASK;
2054 /* what follows is the moral equivalent of:
2056 if (!(Svp = hv_fetch(PL_strtab, str, len, FALSE)))
2057 hv_store(PL_strtab, str, len, Nullsv, hash);
2059 Can't rehash the shared string table, so not sure if it's worth
2060 counting the number of entries in the linked list
2062 xhv = (XPVHV*)SvANY(PL_strtab);
2063 /* assert(xhv_array != 0) */
2065 /* oentry = &(HvARRAY(hv))[hash & (I32) HvMAX(hv)]; */
2066 oentry = &((HE**)xhv->xhv_array)[hash & (I32) xhv->xhv_max];
2067 for (entry = *oentry; entry; i=0, entry = HeNEXT(entry)) {
2068 if (HeHASH(entry) != hash) /* strings can't be equal */
2070 if (HeKLEN(entry) != len)
2072 if (HeKEY(entry) != str && memNE(HeKEY(entry),str,len)) /* is this it? */
2074 if (HeKFLAGS(entry) != flags_masked)
2081 HeKEY_hek(entry) = save_hek_flags(str, len, hash, flags);
2082 HeVAL(entry) = Nullsv;
2083 HeNEXT(entry) = *oentry;
2085 xhv->xhv_keys++; /* HvKEYS(hv)++ */
2086 if (i) { /* initial entry? */
2087 xhv->xhv_fill++; /* HvFILL(hv)++ */
2088 } else if (xhv->xhv_keys > (IV)xhv->xhv_max /* HvKEYS(hv) > HvMAX(hv) */) {
2093 ++HeVAL(entry); /* use value slot as REFCNT */
2094 UNLOCK_STRTAB_MUTEX;
2096 if (flags & HVhek_FREEKEY)
2099 return HeKEY_hek(entry);
2104 =for apidoc hv_assert
2106 Check that a hash is in an internally consistent state.
2112 Perl_hv_assert(pTHX_ HV *hv)
2116 int placeholders = 0;
2119 I32 riter = HvRITER(hv);
2120 HE *eiter = HvEITER(hv);
2122 (void)hv_iterinit(hv);
2124 while ((entry = hv_iternext_flags(hv, HV_ITERNEXT_WANTPLACEHOLDERS))) {
2125 /* sanity check the values */
2126 if (HeVAL(entry) == &PL_sv_placeholder) {
2131 /* sanity check the keys */
2132 if (HeSVKEY(entry)) {
2133 /* Don't know what to check on SV keys. */
2134 } else if (HeKUTF8(entry)) {
2136 if (HeKWASUTF8(entry)) {
2137 PerlIO_printf(Perl_debug_log,
2138 "hash key has both WASUFT8 and UTF8: '%.*s'\n",
2139 (int) HeKLEN(entry), HeKEY(entry));
2142 } else if (HeKWASUTF8(entry)) {
2146 if (!SvTIED_mg((SV*)hv, PERL_MAGIC_tied)) {
2147 if (HvUSEDKEYS(hv) != real) {
2148 PerlIO_printf(Perl_debug_log, "Count %d key(s), but hash reports %d\n",
2149 (int) real, (int) HvUSEDKEYS(hv));
2152 if (HvPLACEHOLDERS(hv) != placeholders) {
2153 PerlIO_printf(Perl_debug_log,
2154 "Count %d placeholder(s), but hash reports %d\n",
2155 (int) placeholders, (int) HvPLACEHOLDERS(hv));
2159 if (withflags && ! HvHASKFLAGS(hv)) {
2160 PerlIO_printf(Perl_debug_log,
2161 "Hash has HASKFLAGS off but I count %d key(s) with flags\n",
2168 HvRITER(hv) = riter; /* Restore hash iterator state */
2169 HvEITER(hv) = eiter;