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 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));
913 /* keysave not in scope - don't understand - NI-S */
914 if (k_flags & HVhek_FREEKEY) {
926 xhv = (XPVHV*)SvANY(hv);
927 if (!xhv->xhv_array /* !HvARRAY(hv) */)
931 const char *keysave = key;
932 key = (char*)bytes_from_utf8((U8*)key, &klen, &is_utf8);
935 k_flags |= HVhek_UTF8;
937 k_flags &= ~HVhek_UTF8;
938 if (key != keysave) {
939 if (k_flags & HVhek_FREEKEY) {
940 /* This shouldn't happen if our caller does what we expect,
941 but strictly the API allows it. */
944 k_flags |= HVhek_WASUTF8 | HVhek_FREEKEY;
946 HvHASKFLAGS_on((SV*)hv);
950 PERL_HASH_INTERNAL(hash, key, klen);
952 if (keysv && (SvIsCOW_shared_hash(keysv))) {
955 PERL_HASH(hash, key, klen);
957 PERL_HASH(hash, key, klen);
960 masked_flags = (k_flags & HVhek_MASK);
962 /* oentry = &(HvARRAY(hv))[hash & (I32) HvMAX(hv)]; */
963 oentry = &((HE**)xhv->xhv_array)[hash & (I32) xhv->xhv_max];
966 for (; entry; i=0, oentry = &HeNEXT(entry), entry = *oentry) {
967 if (HeHASH(entry) != hash) /* strings can't be equal */
969 if (HeKLEN(entry) != (I32)klen)
971 if (HeKEY(entry) != key && memNE(HeKEY(entry),key,klen)) /* is this it? */
973 if ((HeKFLAGS(entry) ^ masked_flags) & HVhek_UTF8)
975 if (k_flags & HVhek_FREEKEY)
978 /* if placeholder is here, it's already been deleted.... */
979 if (HeVAL(entry) == &PL_sv_placeholder)
982 return Nullsv; /* if still SvREADONLY, leave it deleted. */
984 /* okay, really delete the placeholder. */
985 *oentry = HeNEXT(entry);
987 xhv->xhv_fill--; /* HvFILL(hv)-- */
988 if (entry == xhv->xhv_eiter /* HvEITER(hv) */)
991 hv_free_ent(hv, entry);
992 xhv->xhv_keys--; /* HvKEYS(hv)-- */
993 if (xhv->xhv_keys == 0)
995 xhv->xhv_placeholders--;
998 else if (SvREADONLY(hv) && HeVAL(entry) && SvREADONLY(HeVAL(entry))) {
999 S_hv_notallowed(aTHX_ k_flags, key, klen,
1000 "delete readonly key '%"SVf"' from"
1004 if (d_flags & G_DISCARD)
1007 sv = sv_2mortal(HeVAL(entry));
1008 HeVAL(entry) = &PL_sv_placeholder;
1012 * If a restricted hash, rather than really deleting the entry, put
1013 * a placeholder there. This marks the key as being "approved", so
1014 * we can still access via not-really-existing key without raising
1017 if (SvREADONLY(hv)) {
1018 HeVAL(entry) = &PL_sv_placeholder;
1019 /* We'll be saving this slot, so the number of allocated keys
1020 * doesn't go down, but the number placeholders goes up */
1021 xhv->xhv_placeholders++; /* HvPLACEHOLDERS(hv)++ */
1023 *oentry = HeNEXT(entry);
1025 xhv->xhv_fill--; /* HvFILL(hv)-- */
1026 if (entry == xhv->xhv_eiter /* HvEITER(hv) */)
1029 hv_free_ent(hv, entry);
1030 xhv->xhv_keys--; /* HvKEYS(hv)-- */
1031 if (xhv->xhv_keys == 0)
1032 HvHASKFLAGS_off(hv);
1036 if (SvREADONLY(hv)) {
1037 S_hv_notallowed(aTHX_ k_flags, key, klen,
1038 "delete disallowed key '%"SVf"' from"
1042 if (k_flags & HVhek_FREEKEY)
1048 S_hsplit(pTHX_ HV *hv)
1050 register XPVHV* xhv = (XPVHV*)SvANY(hv);
1051 I32 oldsize = (I32) xhv->xhv_max+1; /* HvMAX(hv)+1 (sick) */
1052 register I32 newsize = oldsize * 2;
1054 register char *a = xhv->xhv_array; /* HvARRAY(hv) */
1058 register HE **oentry;
1059 int longest_chain = 0;
1063 #if defined(STRANGE_MALLOC) || defined(MYMALLOC)
1064 Renew(a, PERL_HV_ARRAY_ALLOC_BYTES(newsize), char);
1070 New(2, a, PERL_HV_ARRAY_ALLOC_BYTES(newsize), char);
1075 Copy(xhv->xhv_array /* HvARRAY(hv) */, a, oldsize * sizeof(HE*), char);
1076 if (oldsize >= 64) {
1077 offer_nice_chunk(xhv->xhv_array /* HvARRAY(hv) */,
1078 PERL_HV_ARRAY_ALLOC_BYTES(oldsize));
1081 Safefree(xhv->xhv_array /* HvARRAY(hv) */);
1085 Zero(&a[oldsize * sizeof(HE*)], (newsize-oldsize) * sizeof(HE*), char); /* zero 2nd half*/
1086 xhv->xhv_max = --newsize; /* HvMAX(hv) = --newsize */
1087 xhv->xhv_array = a; /* HvARRAY(hv) = a */
1090 for (i=0; i<oldsize; i++,aep++) {
1091 int left_length = 0;
1092 int right_length = 0;
1094 if (!*aep) /* non-existent */
1097 for (oentry = aep, entry = *aep; entry; entry = *oentry) {
1098 if ((HeHASH(entry) & newsize) != (U32)i) {
1099 *oentry = HeNEXT(entry);
1100 HeNEXT(entry) = *bep;
1102 xhv->xhv_fill++; /* HvFILL(hv)++ */
1108 oentry = &HeNEXT(entry);
1112 if (!*aep) /* everything moved */
1113 xhv->xhv_fill--; /* HvFILL(hv)-- */
1114 /* I think we don't actually need to keep track of the longest length,
1115 merely flag if anything is too long. But for the moment while
1116 developing this code I'll track it. */
1117 if (left_length > longest_chain)
1118 longest_chain = left_length;
1119 if (right_length > longest_chain)
1120 longest_chain = right_length;
1124 /* Pick your policy for "hashing isn't working" here: */
1125 if (longest_chain <= HV_MAX_LENGTH_BEFORE_SPLIT /* split worked? */
1130 if (hv == PL_strtab) {
1131 /* Urg. Someone is doing something nasty to the string table.
1136 /* Awooga. Awooga. Pathological data. */
1137 /*PerlIO_printf(PerlIO_stderr(), "%p %d of %d with %d/%d buckets\n", hv,
1138 longest_chain, HvTOTALKEYS(hv), HvFILL(hv), 1+HvMAX(hv));*/
1141 Newz(2, a, PERL_HV_ARRAY_ALLOC_BYTES(newsize), char);
1142 was_shared = HvSHAREKEYS(hv);
1145 HvSHAREKEYS_off(hv);
1148 aep = (HE **) xhv->xhv_array;
1150 for (i=0; i<newsize; i++,aep++) {
1153 /* We're going to trash this HE's next pointer when we chain it
1154 into the new hash below, so store where we go next. */
1155 HE *next = HeNEXT(entry);
1159 PERL_HASH_INTERNAL(hash, HeKEY(entry), HeKLEN(entry));
1164 = save_hek_flags(HeKEY(entry), HeKLEN(entry),
1165 hash, HeKFLAGS(entry));
1166 unshare_hek (HeKEY_hek(entry));
1167 HeKEY_hek(entry) = new_hek;
1169 /* Not shared, so simply write the new hash in. */
1170 HeHASH(entry) = hash;
1172 /*PerlIO_printf(PerlIO_stderr(), "%d ", HeKFLAGS(entry));*/
1173 HEK_REHASH_on(HeKEY_hek(entry));
1174 /*PerlIO_printf(PerlIO_stderr(), "%d\n", HeKFLAGS(entry));*/
1176 /* Copy oentry to the correct new chain. */
1177 bep = ((HE**)a) + (hash & (I32) xhv->xhv_max);
1179 xhv->xhv_fill++; /* HvFILL(hv)++ */
1180 HeNEXT(entry) = *bep;
1186 Safefree (xhv->xhv_array);
1187 xhv->xhv_array = a; /* HvARRAY(hv) = a */
1191 Perl_hv_ksplit(pTHX_ HV *hv, IV newmax)
1193 register XPVHV* xhv = (XPVHV*)SvANY(hv);
1194 I32 oldsize = (I32) xhv->xhv_max+1; /* HvMAX(hv)+1 (sick) */
1195 register I32 newsize;
1201 register HE **oentry;
1203 newsize = (I32) newmax; /* possible truncation here */
1204 if (newsize != newmax || newmax <= oldsize)
1206 while ((newsize & (1 + ~newsize)) != newsize) {
1207 newsize &= ~(newsize & (1 + ~newsize)); /* get proper power of 2 */
1209 if (newsize < newmax)
1211 if (newsize < newmax)
1212 return; /* overflow detection */
1214 a = xhv->xhv_array; /* HvARRAY(hv) */
1217 #if defined(STRANGE_MALLOC) || defined(MYMALLOC)
1218 Renew(a, PERL_HV_ARRAY_ALLOC_BYTES(newsize), char);
1224 New(2, a, PERL_HV_ARRAY_ALLOC_BYTES(newsize), char);
1229 Copy(xhv->xhv_array /* HvARRAY(hv) */, a, oldsize * sizeof(HE*), char);
1230 if (oldsize >= 64) {
1231 offer_nice_chunk(xhv->xhv_array /* HvARRAY(hv) */,
1232 PERL_HV_ARRAY_ALLOC_BYTES(oldsize));
1235 Safefree(xhv->xhv_array /* HvARRAY(hv) */);
1238 Zero(&a[oldsize * sizeof(HE*)], (newsize-oldsize) * sizeof(HE*), char); /* zero 2nd half*/
1241 Newz(0, a, PERL_HV_ARRAY_ALLOC_BYTES(newsize), char);
1243 xhv->xhv_max = --newsize; /* HvMAX(hv) = --newsize */
1244 xhv->xhv_array = a; /* HvARRAY(hv) = a */
1245 if (!xhv->xhv_fill /* !HvFILL(hv) */) /* skip rest if no entries */
1249 for (i=0; i<oldsize; i++,aep++) {
1250 if (!*aep) /* non-existent */
1252 for (oentry = aep, entry = *aep; entry; entry = *oentry) {
1253 if ((j = (HeHASH(entry) & newsize)) != i) {
1255 *oentry = HeNEXT(entry);
1256 if (!(HeNEXT(entry) = aep[j]))
1257 xhv->xhv_fill++; /* HvFILL(hv)++ */
1262 oentry = &HeNEXT(entry);
1264 if (!*aep) /* everything moved */
1265 xhv->xhv_fill--; /* HvFILL(hv)-- */
1272 Creates a new HV. The reference count is set to 1.
1281 register XPVHV* xhv;
1283 hv = (HV*)NEWSV(502,0);
1284 sv_upgrade((SV *)hv, SVt_PVHV);
1285 xhv = (XPVHV*)SvANY(hv);
1288 #ifndef NODEFAULT_SHAREKEYS
1289 HvSHAREKEYS_on(hv); /* key-sharing on by default */
1292 xhv->xhv_max = 7; /* HvMAX(hv) = 7 (start with 8 buckets) */
1293 xhv->xhv_fill = 0; /* HvFILL(hv) = 0 */
1294 xhv->xhv_pmroot = 0; /* HvPMROOT(hv) = 0 */
1295 (void)hv_iterinit(hv); /* so each() will start off right */
1300 Perl_newHVhv(pTHX_ HV *ohv)
1303 STRLEN hv_max, hv_fill;
1305 if (!ohv || (hv_fill = HvFILL(ohv)) == 0)
1307 hv_max = HvMAX(ohv);
1309 if (!SvMAGICAL((SV *)ohv)) {
1310 /* It's an ordinary hash, so copy it fast. AMS 20010804 */
1312 bool shared = !!HvSHAREKEYS(ohv);
1313 HE **ents, **oents = (HE **)HvARRAY(ohv);
1315 New(0, a, PERL_HV_ARRAY_ALLOC_BYTES(hv_max+1), char);
1318 /* In each bucket... */
1319 for (i = 0; i <= hv_max; i++) {
1320 HE *prev = NULL, *ent = NULL, *oent = oents[i];
1327 /* Copy the linked list of entries. */
1328 for (oent = oents[i]; oent; oent = HeNEXT(oent)) {
1329 U32 hash = HeHASH(oent);
1330 char *key = HeKEY(oent);
1331 STRLEN len = HeKLEN(oent);
1332 int flags = HeKFLAGS(oent);
1335 HeVAL(ent) = newSVsv(HeVAL(oent));
1337 = shared ? share_hek_flags(key, len, hash, flags)
1338 : save_hek_flags(key, len, hash, flags);
1349 HvFILL(hv) = hv_fill;
1350 HvTOTALKEYS(hv) = HvTOTALKEYS(ohv);
1354 /* Iterate over ohv, copying keys and values one at a time. */
1356 I32 riter = HvRITER(ohv);
1357 HE *eiter = HvEITER(ohv);
1359 /* Can we use fewer buckets? (hv_max is always 2^n-1) */
1360 while (hv_max && hv_max + 1 >= hv_fill * 2)
1361 hv_max = hv_max / 2;
1365 while ((entry = hv_iternext_flags(ohv, 0))) {
1366 hv_store_flags(hv, HeKEY(entry), HeKLEN(entry),
1367 newSVsv(HeVAL(entry)), HeHASH(entry),
1370 HvRITER(ohv) = riter;
1371 HvEITER(ohv) = eiter;
1378 Perl_hv_free_ent(pTHX_ HV *hv, register HE *entry)
1385 if (val && isGV(val) && GvCVu(val) && HvNAME(hv))
1386 PL_sub_generation++; /* may be deletion of method from stash */
1388 if (HeKLEN(entry) == HEf_SVKEY) {
1389 SvREFCNT_dec(HeKEY_sv(entry));
1390 Safefree(HeKEY_hek(entry));
1392 else if (HvSHAREKEYS(hv))
1393 unshare_hek(HeKEY_hek(entry));
1395 Safefree(HeKEY_hek(entry));
1400 Perl_hv_delayfree_ent(pTHX_ HV *hv, register HE *entry)
1404 if (isGV(HeVAL(entry)) && GvCVu(HeVAL(entry)) && HvNAME(hv))
1405 PL_sub_generation++; /* may be deletion of method from stash */
1406 sv_2mortal(HeVAL(entry)); /* free between statements */
1407 if (HeKLEN(entry) == HEf_SVKEY) {
1408 sv_2mortal(HeKEY_sv(entry));
1409 Safefree(HeKEY_hek(entry));
1411 else if (HvSHAREKEYS(hv))
1412 unshare_hek(HeKEY_hek(entry));
1414 Safefree(HeKEY_hek(entry));
1419 =for apidoc hv_clear
1421 Clears a hash, making it empty.
1427 Perl_hv_clear(pTHX_ HV *hv)
1429 register XPVHV* xhv;
1433 DEBUG_A(Perl_hv_assert(aTHX_ hv));
1435 xhv = (XPVHV*)SvANY(hv);
1437 if (SvREADONLY(hv) && xhv->xhv_array != NULL) {
1438 /* restricted hash: convert all keys to placeholders */
1441 for (i = 0; i <= (I32) xhv->xhv_max; i++) {
1442 entry = ((HE**)xhv->xhv_array)[i];
1443 for (; entry; entry = HeNEXT(entry)) {
1444 /* not already placeholder */
1445 if (HeVAL(entry) != &PL_sv_placeholder) {
1446 if (HeVAL(entry) && SvREADONLY(HeVAL(entry))) {
1447 SV* keysv = hv_iterkeysv(entry);
1449 "Attempt to delete readonly key '%"SVf"' from a restricted hash",
1452 SvREFCNT_dec(HeVAL(entry));
1453 HeVAL(entry) = &PL_sv_placeholder;
1454 xhv->xhv_placeholders++; /* HvPLACEHOLDERS(hv)++ */
1462 xhv->xhv_placeholders = 0; /* HvPLACEHOLDERS(hv) = 0 */
1463 if (xhv->xhv_array /* HvARRAY(hv) */)
1464 (void)memzero(xhv->xhv_array /* HvARRAY(hv) */,
1465 (xhv->xhv_max+1 /* HvMAX(hv)+1 */) * sizeof(HE*));
1470 HvHASKFLAGS_off(hv);
1477 =for apidoc hv_clear_placeholders
1479 Clears any placeholders from a hash. If a restricted hash has any of its keys
1480 marked as readonly and the key is subsequently deleted, the key is not actually
1481 deleted but is marked by assigning it a value of &PL_sv_placeholder. This tags
1482 it so it will be ignored by future operations such as iterating over the hash,
1483 but will still allow the hash to have a value reaasigned to the key at some
1484 future point. This function clears any such placeholder keys from the hash.
1485 See Hash::Util::lock_keys() for an example of its use.
1491 Perl_hv_clear_placeholders(pTHX_ HV *hv)
1494 items = (I32)HvPLACEHOLDERS(hv);
1497 I32 riter = HvRITER(hv);
1498 HE *eiter = HvEITER(hv);
1500 /* This may look suboptimal with the items *after* the iternext, but
1501 it's quite deliberate. We only get here with items==0 if we've
1502 just deleted the last placeholder in the hash. If we've just done
1503 that then it means that the hash is in lazy delete mode, and the
1504 HE is now only referenced in our iterator. If we just quit the loop
1505 and discarded our iterator then the HE leaks. So we do the && the
1506 other way to ensure iternext is called just one more time, which
1507 has the side effect of triggering the lazy delete. */
1508 while ((entry = hv_iternext_flags(hv, HV_ITERNEXT_WANTPLACEHOLDERS))
1510 SV *val = hv_iterval(hv, entry);
1512 if (val == &PL_sv_placeholder) {
1514 /* It seems that I have to go back in the front of the hash
1515 API to delete a hash, even though I have a HE structure
1516 pointing to the very entry I want to delete, and could hold
1517 onto the previous HE that points to it. And it's easier to
1518 go in with SVs as I can then specify the precomputed hash,
1519 and don't have fun and games with utf8 keys. */
1520 SV *key = hv_iterkeysv(entry);
1522 hv_delete_ent (hv, key, G_DISCARD, HeHASH(entry));
1526 HvRITER(hv) = riter;
1527 HvEITER(hv) = eiter;
1532 S_hfreeentries(pTHX_ HV *hv)
1534 register HE **array;
1536 register HE *oentry = Null(HE*);
1547 array = HvARRAY(hv);
1548 /* make everyone else think the array is empty, so that the destructors
1549 * called for freed entries can't recusively mess with us */
1550 HvARRAY(hv) = Null(HE**);
1552 ((XPVHV*) SvANY(hv))->xhv_keys = 0;
1558 entry = HeNEXT(entry);
1559 hv_free_ent(hv, oentry);
1564 entry = array[riter];
1567 HvARRAY(hv) = array;
1568 (void)hv_iterinit(hv);
1572 =for apidoc hv_undef
1580 Perl_hv_undef(pTHX_ HV *hv)
1582 register XPVHV* xhv;
1585 DEBUG_A(Perl_hv_assert(aTHX_ hv));
1586 xhv = (XPVHV*)SvANY(hv);
1588 Safefree(xhv->xhv_array /* HvARRAY(hv) */);
1591 hv_delete(PL_stashcache, HvNAME(hv), strlen(HvNAME(hv)), G_DISCARD);
1592 Safefree(HvNAME(hv));
1595 xhv->xhv_max = 7; /* HvMAX(hv) = 7 (it's a normal hash) */
1596 xhv->xhv_array = 0; /* HvARRAY(hv) = 0 */
1597 xhv->xhv_placeholders = 0; /* HvPLACEHOLDERS(hv) = 0 */
1604 =for apidoc hv_iterinit
1606 Prepares a starting point to traverse a hash table. Returns the number of
1607 keys in the hash (i.e. the same as C<HvKEYS(tb)>). The return value is
1608 currently only meaningful for hashes without tie magic.
1610 NOTE: Before version 5.004_65, C<hv_iterinit> used to return the number of
1611 hash buckets that happen to be in use. If you still need that esoteric
1612 value, you can get it through the macro C<HvFILL(tb)>.
1619 Perl_hv_iterinit(pTHX_ HV *hv)
1621 register XPVHV* xhv;
1625 Perl_croak(aTHX_ "Bad hash");
1626 xhv = (XPVHV*)SvANY(hv);
1627 entry = xhv->xhv_eiter; /* HvEITER(hv) */
1628 if (entry && HvLAZYDEL(hv)) { /* was deleted earlier? */
1630 hv_free_ent(hv, entry);
1632 xhv->xhv_riter = -1; /* HvRITER(hv) = -1 */
1633 xhv->xhv_eiter = Null(HE*); /* HvEITER(hv) = Null(HE*) */
1634 /* used to be xhv->xhv_fill before 5.004_65 */
1635 return XHvTOTALKEYS(xhv);
1638 =for apidoc hv_iternext
1640 Returns entries from a hash iterator. See C<hv_iterinit>.
1642 You may call C<hv_delete> or C<hv_delete_ent> on the hash entry that the
1643 iterator currently points to, without losing your place or invalidating your
1644 iterator. Note that in this case the current entry is deleted from the hash
1645 with your iterator holding the last reference to it. Your iterator is flagged
1646 to free the entry on the next call to C<hv_iternext>, so you must not discard
1647 your iterator immediately else the entry will leak - call C<hv_iternext> to
1648 trigger the resource deallocation.
1654 Perl_hv_iternext(pTHX_ HV *hv)
1656 return hv_iternext_flags(hv, 0);
1660 =for apidoc hv_iternext_flags
1662 Returns entries from a hash iterator. See C<hv_iterinit> and C<hv_iternext>.
1663 The C<flags> value will normally be zero; if HV_ITERNEXT_WANTPLACEHOLDERS is
1664 set the placeholders keys (for restricted hashes) will be returned in addition
1665 to normal keys. By default placeholders are automatically skipped over.
1666 Currently a placeholder is implemented with a value that is
1667 C<&Perl_sv_placeholder>. Note that the implementation of placeholders and
1668 restricted hashes may change, and the implementation currently is
1669 insufficiently abstracted for any change to be tidy.
1675 Perl_hv_iternext_flags(pTHX_ HV *hv, I32 flags)
1677 register XPVHV* xhv;
1683 Perl_croak(aTHX_ "Bad hash");
1684 xhv = (XPVHV*)SvANY(hv);
1685 oldentry = entry = xhv->xhv_eiter; /* HvEITER(hv) */
1687 if ((mg = SvTIED_mg((SV*)hv, PERL_MAGIC_tied))) {
1688 SV *key = sv_newmortal();
1690 sv_setsv(key, HeSVKEY_force(entry));
1691 SvREFCNT_dec(HeSVKEY(entry)); /* get rid of previous key */
1697 /* one HE per MAGICAL hash */
1698 xhv->xhv_eiter = entry = new_HE(); /* HvEITER(hv) = new_HE() */
1700 Newz(54, k, HEK_BASESIZE + sizeof(SV*), char);
1702 HeKEY_hek(entry) = hek;
1703 HeKLEN(entry) = HEf_SVKEY;
1705 magic_nextpack((SV*) hv,mg,key);
1707 /* force key to stay around until next time */
1708 HeSVKEY_set(entry, SvREFCNT_inc(key));
1709 return entry; /* beware, hent_val is not set */
1712 SvREFCNT_dec(HeVAL(entry));
1713 Safefree(HeKEY_hek(entry));
1715 xhv->xhv_eiter = Null(HE*); /* HvEITER(hv) = Null(HE*) */
1718 #ifdef DYNAMIC_ENV_FETCH /* set up %ENV for iteration */
1719 if (!entry && SvRMAGICAL((SV*)hv) && mg_find((SV*)hv, PERL_MAGIC_env))
1723 if (!xhv->xhv_array /* !HvARRAY(hv) */)
1724 Newz(506, xhv->xhv_array /* HvARRAY(hv) */,
1725 PERL_HV_ARRAY_ALLOC_BYTES(xhv->xhv_max+1 /* HvMAX(hv)+1 */),
1727 /* At start of hash, entry is NULL. */
1730 entry = HeNEXT(entry);
1731 if (!(flags & HV_ITERNEXT_WANTPLACEHOLDERS)) {
1733 * Skip past any placeholders -- don't want to include them in
1736 while (entry && HeVAL(entry) == &PL_sv_placeholder) {
1737 entry = HeNEXT(entry);
1742 /* OK. Come to the end of the current list. Grab the next one. */
1744 xhv->xhv_riter++; /* HvRITER(hv)++ */
1745 if (xhv->xhv_riter > (I32)xhv->xhv_max /* HvRITER(hv) > HvMAX(hv) */) {
1746 /* There is no next one. End of the hash. */
1747 xhv->xhv_riter = -1; /* HvRITER(hv) = -1 */
1750 /* entry = (HvARRAY(hv))[HvRITER(hv)]; */
1751 entry = ((HE**)xhv->xhv_array)[xhv->xhv_riter];
1753 if (!(flags & HV_ITERNEXT_WANTPLACEHOLDERS)) {
1754 /* If we have an entry, but it's a placeholder, don't count it.
1756 while (entry && HeVAL(entry) == &PL_sv_placeholder)
1757 entry = HeNEXT(entry);
1759 /* Will loop again if this linked list starts NULL
1760 (for HV_ITERNEXT_WANTPLACEHOLDERS)
1761 or if we run through it and find only placeholders. */
1764 if (oldentry && HvLAZYDEL(hv)) { /* was deleted earlier? */
1766 hv_free_ent(hv, oldentry);
1769 /*if (HvREHASH(hv) && entry && !HeKREHASH(entry))
1770 PerlIO_printf(PerlIO_stderr(), "Awooga %p %p\n", hv, entry);*/
1772 xhv->xhv_eiter = entry; /* HvEITER(hv) = entry */
1777 =for apidoc hv_iterkey
1779 Returns the key from the current position of the hash iterator. See
1786 Perl_hv_iterkey(pTHX_ register HE *entry, I32 *retlen)
1788 if (HeKLEN(entry) == HEf_SVKEY) {
1790 char *p = SvPV(HeKEY_sv(entry), len);
1795 *retlen = HeKLEN(entry);
1796 return HeKEY(entry);
1800 /* unlike hv_iterval(), this always returns a mortal copy of the key */
1802 =for apidoc hv_iterkeysv
1804 Returns the key as an C<SV*> from the current position of the hash
1805 iterator. The return value will always be a mortal copy of the key. Also
1812 Perl_hv_iterkeysv(pTHX_ register HE *entry)
1814 if (HeKLEN(entry) != HEf_SVKEY) {
1815 HEK *hek = HeKEY_hek(entry);
1816 int flags = HEK_FLAGS(hek);
1819 if (flags & HVhek_WASUTF8) {
1821 Andreas would like keys he put in as utf8 to come back as utf8
1823 STRLEN utf8_len = HEK_LEN(hek);
1824 U8 *as_utf8 = bytes_to_utf8 ((U8*)HEK_KEY(hek), &utf8_len);
1826 sv = newSVpvn ((char*)as_utf8, utf8_len);
1828 Safefree (as_utf8); /* bytes_to_utf8() allocates a new string */
1829 } else if (flags & HVhek_REHASH) {
1830 /* We don't have a pointer to the hv, so we have to replicate the
1831 flag into every HEK. This hv is using custom a hasing
1832 algorithm. Hence we can't return a shared string scalar, as
1833 that would contain the (wrong) hash value, and might get passed
1834 into an hv routine with a regular hash */
1836 sv = newSVpvn (HEK_KEY(hek), HEK_LEN(hek));
1840 sv = newSVpvn_share(HEK_KEY(hek),
1841 (HEK_UTF8(hek) ? -HEK_LEN(hek) : HEK_LEN(hek)),
1844 return sv_2mortal(sv);
1846 return sv_mortalcopy(HeKEY_sv(entry));
1850 =for apidoc hv_iterval
1852 Returns the value from the current position of the hash iterator. See
1859 Perl_hv_iterval(pTHX_ HV *hv, register HE *entry)
1861 if (SvRMAGICAL(hv)) {
1862 if (mg_find((SV*)hv, PERL_MAGIC_tied)) {
1863 SV* sv = sv_newmortal();
1864 if (HeKLEN(entry) == HEf_SVKEY)
1865 mg_copy((SV*)hv, sv, (char*)HeKEY_sv(entry), HEf_SVKEY);
1866 else mg_copy((SV*)hv, sv, HeKEY(entry), HeKLEN(entry));
1870 return HeVAL(entry);
1874 =for apidoc hv_iternextsv
1876 Performs an C<hv_iternext>, C<hv_iterkey>, and C<hv_iterval> in one
1883 Perl_hv_iternextsv(pTHX_ HV *hv, char **key, I32 *retlen)
1886 if ( (he = hv_iternext_flags(hv, 0)) == NULL)
1888 *key = hv_iterkey(he, retlen);
1889 return hv_iterval(hv, he);
1893 =for apidoc hv_magic
1895 Adds magic to a hash. See C<sv_magic>.
1901 Perl_hv_magic(pTHX_ HV *hv, GV *gv, int how)
1903 sv_magic((SV*)hv, (SV*)gv, how, Nullch, 0);
1906 #if 0 /* use the macro from hv.h instead */
1909 Perl_sharepvn(pTHX_ const char *sv, I32 len, U32 hash)
1911 return HEK_KEY(share_hek(sv, len, hash));
1916 /* possibly free a shared string if no one has access to it
1917 * len and hash must both be valid for str.
1920 Perl_unsharepvn(pTHX_ const char *str, I32 len, U32 hash)
1922 unshare_hek_or_pvn (NULL, str, len, hash);
1927 Perl_unshare_hek(pTHX_ HEK *hek)
1929 unshare_hek_or_pvn(hek, NULL, 0, 0);
1932 /* possibly free a shared string if no one has access to it
1933 hek if non-NULL takes priority over the other 3, else str, len and hash
1934 are used. If so, len and hash must both be valid for str.
1937 S_unshare_hek_or_pvn(pTHX_ HEK *hek, const char *str, I32 len, U32 hash)
1939 register XPVHV* xhv;
1941 register HE **oentry;
1944 bool is_utf8 = FALSE;
1946 const char *save = str;
1949 hash = HEK_HASH(hek);
1950 } else if (len < 0) {
1951 STRLEN tmplen = -len;
1953 /* See the note in hv_fetch(). --jhi */
1954 str = (char*)bytes_from_utf8((U8*)str, &tmplen, &is_utf8);
1957 k_flags = HVhek_UTF8;
1959 k_flags |= HVhek_WASUTF8 | HVhek_FREEKEY;
1962 /* what follows is the moral equivalent of:
1963 if ((Svp = hv_fetch(PL_strtab, tmpsv, FALSE, hash))) {
1964 if (--*Svp == Nullsv)
1965 hv_delete(PL_strtab, str, len, G_DISCARD, hash);
1967 xhv = (XPVHV*)SvANY(PL_strtab);
1968 /* assert(xhv_array != 0) */
1970 /* oentry = &(HvARRAY(hv))[hash & (I32) HvMAX(hv)]; */
1971 oentry = &((HE**)xhv->xhv_array)[hash & (I32) xhv->xhv_max];
1973 for (entry = *oentry; entry; i=0, oentry = &HeNEXT(entry), entry = *oentry) {
1974 if (HeKEY_hek(entry) != hek)
1980 int flags_masked = k_flags & HVhek_MASK;
1981 for (entry = *oentry; entry; i=0, oentry = &HeNEXT(entry), entry = *oentry) {
1982 if (HeHASH(entry) != hash) /* strings can't be equal */
1984 if (HeKLEN(entry) != len)
1986 if (HeKEY(entry) != str && memNE(HeKEY(entry),str,len)) /* is this it? */
1988 if (HeKFLAGS(entry) != flags_masked)
1996 if (--HeVAL(entry) == Nullsv) {
1997 *oentry = HeNEXT(entry);
1999 xhv->xhv_fill--; /* HvFILL(hv)-- */
2000 Safefree(HeKEY_hek(entry));
2002 xhv->xhv_keys--; /* HvKEYS(hv)-- */
2006 UNLOCK_STRTAB_MUTEX;
2007 if (!found && ckWARN_d(WARN_INTERNAL))
2008 Perl_warner(aTHX_ packWARN(WARN_INTERNAL),
2009 "Attempt to free non-existent shared string '%s'%s",
2010 hek ? HEK_KEY(hek) : str,
2011 (k_flags & HVhek_UTF8) ? " (utf8)" : "");
2012 if (k_flags & HVhek_FREEKEY)
2016 /* get a (constant) string ptr from the global string table
2017 * string will get added if it is not already there.
2018 * len and hash must both be valid for str.
2021 Perl_share_hek(pTHX_ const char *str, I32 len, register U32 hash)
2023 bool is_utf8 = FALSE;
2025 const char *save = str;
2028 STRLEN tmplen = -len;
2030 /* See the note in hv_fetch(). --jhi */
2031 str = (char*)bytes_from_utf8((U8*)str, &tmplen, &is_utf8);
2033 /* If we were able to downgrade here, then than means that we were passed
2034 in a key which only had chars 0-255, but was utf8 encoded. */
2037 /* If we found we were able to downgrade the string to bytes, then
2038 we should flag that it needs upgrading on keys or each. Also flag
2039 that we need share_hek_flags to free the string. */
2041 flags |= HVhek_WASUTF8 | HVhek_FREEKEY;
2044 return share_hek_flags (str, len, hash, flags);
2048 S_share_hek_flags(pTHX_ const char *str, I32 len, register U32 hash, int flags)
2050 register XPVHV* xhv;
2052 register HE **oentry;
2055 int flags_masked = flags & HVhek_MASK;
2057 /* what follows is the moral equivalent of:
2059 if (!(Svp = hv_fetch(PL_strtab, str, len, FALSE)))
2060 hv_store(PL_strtab, str, len, Nullsv, hash);
2062 Can't rehash the shared string table, so not sure if it's worth
2063 counting the number of entries in the linked list
2065 xhv = (XPVHV*)SvANY(PL_strtab);
2066 /* assert(xhv_array != 0) */
2068 /* oentry = &(HvARRAY(hv))[hash & (I32) HvMAX(hv)]; */
2069 oentry = &((HE**)xhv->xhv_array)[hash & (I32) xhv->xhv_max];
2070 for (entry = *oentry; entry; i=0, entry = HeNEXT(entry)) {
2071 if (HeHASH(entry) != hash) /* strings can't be equal */
2073 if (HeKLEN(entry) != len)
2075 if (HeKEY(entry) != str && memNE(HeKEY(entry),str,len)) /* is this it? */
2077 if (HeKFLAGS(entry) != flags_masked)
2084 HeKEY_hek(entry) = save_hek_flags(str, len, hash, flags);
2085 HeVAL(entry) = Nullsv;
2086 HeNEXT(entry) = *oentry;
2088 xhv->xhv_keys++; /* HvKEYS(hv)++ */
2089 if (i) { /* initial entry? */
2090 xhv->xhv_fill++; /* HvFILL(hv)++ */
2091 } else if (xhv->xhv_keys > (IV)xhv->xhv_max /* HvKEYS(hv) > HvMAX(hv) */) {
2096 ++HeVAL(entry); /* use value slot as REFCNT */
2097 UNLOCK_STRTAB_MUTEX;
2099 if (flags & HVhek_FREEKEY)
2102 return HeKEY_hek(entry);
2107 =for apidoc hv_assert
2109 Check that a hash is in an internally consistent state.
2115 Perl_hv_assert(pTHX_ HV *hv)
2119 int placeholders = 0;
2122 I32 riter = HvRITER(hv);
2123 HE *eiter = HvEITER(hv);
2125 (void)hv_iterinit(hv);
2127 while ((entry = hv_iternext_flags(hv, HV_ITERNEXT_WANTPLACEHOLDERS))) {
2128 /* sanity check the values */
2129 if (HeVAL(entry) == &PL_sv_placeholder) {
2134 /* sanity check the keys */
2135 if (HeSVKEY(entry)) {
2136 /* Don't know what to check on SV keys. */
2137 } else if (HeKUTF8(entry)) {
2139 if (HeKWASUTF8(entry)) {
2140 PerlIO_printf(Perl_debug_log,
2141 "hash key has both WASUFT8 and UTF8: '%.*s'\n",
2142 (int) HeKLEN(entry), HeKEY(entry));
2145 } else if (HeKWASUTF8(entry)) {
2149 if (!SvTIED_mg((SV*)hv, PERL_MAGIC_tied)) {
2150 if (HvUSEDKEYS(hv) != real) {
2151 PerlIO_printf(Perl_debug_log, "Count %d key(s), but hash reports %d\n",
2152 (int) real, (int) HvUSEDKEYS(hv));
2155 if (HvPLACEHOLDERS(hv) != placeholders) {
2156 PerlIO_printf(Perl_debug_log,
2157 "Count %d placeholder(s), but hash reports %d\n",
2158 (int) placeholders, (int) HvPLACEHOLDERS(hv));
2162 if (withflags && ! HvHASKFLAGS(hv)) {
2163 PerlIO_printf(Perl_debug_log,
2164 "Hash has HASKFLAGS off but I count %d key(s) with flags\n",
2171 HvRITER(hv) = riter; /* Restore hash iterator state */
2172 HvEITER(hv) = eiter;