3 * Copyright (C) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
4 * 2000, 2001, 2002, 2003, by Larry Wall and others
6 * You may distribute under the terms of either the GNU General Public
7 * License or the Artistic License, as specified in the README file.
12 * "I sit beside the fire and think of all that I have seen." --Bilbo
16 =head1 Hash Manipulation Functions
21 #define PERL_HASH_INTERNAL_ACCESS
24 #define HV_MAX_LENGTH_BEFORE_SPLIT 14
34 PL_he_root = HeNEXT(he);
43 HeNEXT(p) = (HE*)PL_he_root;
54 New(54, ptr, 1008/sizeof(XPV), XPV);
55 ptr->xpv_pv = (char*)PL_he_arenaroot;
56 PL_he_arenaroot = ptr;
59 heend = &he[1008 / sizeof(HE) - 1];
62 HeNEXT(he) = (HE*)(he + 1);
70 #define new_HE() (HE*)safemalloc(sizeof(HE))
71 #define del_HE(p) safefree((char*)p)
75 #define new_HE() new_he()
76 #define del_HE(p) del_he(p)
81 S_save_hek_flags(pTHX_ const char *str, I32 len, U32 hash, int flags)
86 New(54, k, HEK_BASESIZE + len + 2, char);
88 Copy(str, HEK_KEY(hek), len, char);
89 HEK_KEY(hek)[len] = 0;
92 HEK_FLAGS(hek) = (unsigned char)flags;
96 /* free the pool of temporary HE/HEK pairs retunrned by hv_fetch_ent
100 Perl_free_tied_hv_pool(pTHX)
103 HE *he = PL_hv_fetch_ent_mh;
105 Safefree(HeKEY_hek(he));
110 PL_hv_fetch_ent_mh = Nullhe;
113 #if defined(USE_ITHREADS)
115 Perl_he_dup(pTHX_ HE *e, bool shared, CLONE_PARAMS* param)
121 /* look for it in the table first */
122 ret = (HE*)ptr_table_fetch(PL_ptr_table, e);
126 /* create anew and remember what it is */
128 ptr_table_store(PL_ptr_table, e, ret);
130 HeNEXT(ret) = he_dup(HeNEXT(e),shared, param);
131 if (HeKLEN(e) == HEf_SVKEY) {
133 New(54, k, HEK_BASESIZE + sizeof(SV*), char);
134 HeKEY_hek(ret) = (HEK*)k;
135 HeKEY_sv(ret) = SvREFCNT_inc(sv_dup(HeKEY_sv(e), param));
138 HeKEY_hek(ret) = share_hek_flags(HeKEY(e), HeKLEN(e), HeHASH(e),
141 HeKEY_hek(ret) = save_hek_flags(HeKEY(e), HeKLEN(e), HeHASH(e),
143 HeVAL(ret) = SvREFCNT_inc(sv_dup(HeVAL(e), param));
146 #endif /* USE_ITHREADS */
149 S_hv_notallowed(pTHX_ int flags, const char *key, I32 klen,
152 SV *sv = sv_newmortal(), *esv = sv_newmortal();
153 if (!(flags & HVhek_FREEKEY)) {
154 sv_setpvn(sv, key, klen);
157 /* Need to free saved eventually assign to mortal SV */
158 /* XXX is this line an error ???: SV *sv = sv_newmortal(); */
159 sv_usepvn(sv, (char *) key, klen);
161 if (flags & HVhek_UTF8) {
164 Perl_sv_setpvf(aTHX_ esv, "Attempt to %s a restricted hash", msg);
165 Perl_croak(aTHX_ SvPVX(esv), sv);
168 /* (klen == HEf_SVKEY) is special for MAGICAL hv entries, meaning key slot
171 #define HV_FETCH_ISSTORE 0x01
172 #define HV_FETCH_ISEXISTS 0x02
173 #define HV_FETCH_LVALUE 0x04
174 #define HV_FETCH_JUST_SV 0x08
179 Stores an SV in a hash. The hash key is specified as C<key> and C<klen> is
180 the length of the key. The C<hash> parameter is the precomputed hash
181 value; if it is zero then Perl will compute it. The return value will be
182 NULL if the operation failed or if the value did not need to be actually
183 stored within the hash (as in the case of tied hashes). Otherwise it can
184 be dereferenced to get the original C<SV*>. Note that the caller is
185 responsible for suitably incrementing the reference count of C<val> before
186 the call, and decrementing it if the function returned NULL. Effectively
187 a successful hv_store takes ownership of one reference to C<val>. This is
188 usually what you want; a newly created SV has a reference count of one, so
189 if all your code does is create SVs then store them in a hash, hv_store
190 will own the only reference to the new SV, and your code doesn't need to do
191 anything further to tidy up. hv_store is not implemented as a call to
192 hv_store_ent, and does not create a temporary SV for the key, so if your
193 key data is not already in SV form then use hv_store in preference to
196 See L<perlguts/"Understanding the Magic of Tied Hashes and Arrays"> for more
197 information on how to use this function on tied hashes.
203 Perl_hv_store(pTHX_ HV *hv, const char *key, I32 klen_i32, SV *val, U32 hash)
216 hek = hv_fetch_common (hv, NULL, key, klen, flags,
217 (HV_FETCH_ISSTORE|HV_FETCH_JUST_SV), val, 0);
218 return hek ? &HeVAL(hek) : NULL;
222 Perl_hv_store_flags(pTHX_ HV *hv, const char *key, I32 klen, SV *val,
223 register U32 hash, int flags)
225 HE *hek = hv_fetch_common (hv, NULL, key, klen, flags,
226 (HV_FETCH_ISSTORE|HV_FETCH_JUST_SV), val, hash);
227 return hek ? &HeVAL(hek) : NULL;
231 =for apidoc hv_store_ent
233 Stores C<val> in a hash. The hash key is specified as C<key>. The C<hash>
234 parameter is the precomputed hash value; if it is zero then Perl will
235 compute it. The return value is the new hash entry so created. It will be
236 NULL if the operation failed or if the value did not need to be actually
237 stored within the hash (as in the case of tied hashes). Otherwise the
238 contents of the return value can be accessed using the C<He?> macros
239 described here. Note that the caller is responsible for suitably
240 incrementing the reference count of C<val> before the call, and
241 decrementing it if the function returned NULL. Effectively a successful
242 hv_store_ent takes ownership of one reference to C<val>. This is
243 usually what you want; a newly created SV has a reference count of one, so
244 if all your code does is create SVs then store them in a hash, hv_store
245 will own the only reference to the new SV, and your code doesn't need to do
246 anything further to tidy up. Note that hv_store_ent only reads the C<key>;
247 unlike C<val> it does not take ownership of it, so maintaining the correct
248 reference count on C<key> is entirely the caller's responsibility. hv_store
249 is not implemented as a call to hv_store_ent, and does not create a temporary
250 SV for the key, so if your key data is not already in SV form then use
251 hv_store in preference to hv_store_ent.
253 See L<perlguts/"Understanding the Magic of Tied Hashes and Arrays"> for more
254 information on how to use this function on tied hashes.
260 Perl_hv_store_ent(pTHX_ HV *hv, SV *keysv, SV *val, U32 hash)
262 return hv_fetch_common(hv, keysv, NULL, 0, 0, HV_FETCH_ISSTORE, val, hash);
266 =for apidoc hv_exists
268 Returns a boolean indicating whether the specified hash key exists. The
269 C<klen> is the length of the key.
275 Perl_hv_exists(pTHX_ HV *hv, const char *key, I32 klen_i32)
287 return hv_fetch_common(hv, NULL, key, klen, flags, HV_FETCH_ISEXISTS, 0, 0)
294 Returns the SV which corresponds to the specified key in the hash. The
295 C<klen> is the length of the key. If C<lval> is set then the fetch will be
296 part of a store. Check that the return value is non-null before
297 dereferencing it to an C<SV*>.
299 See L<perlguts/"Understanding the Magic of Tied Hashes and Arrays"> for more
300 information on how to use this function on tied hashes.
306 Perl_hv_fetch(pTHX_ HV *hv, const char *key, I32 klen_i32, I32 lval)
319 hek = hv_fetch_common (hv, NULL, key, klen, flags,
320 HV_FETCH_JUST_SV | (lval ? HV_FETCH_LVALUE : 0),
322 return hek ? &HeVAL(hek) : NULL;
326 =for apidoc hv_exists_ent
328 Returns a boolean indicating whether the specified hash key exists. C<hash>
329 can be a valid precomputed hash value, or 0 to ask for it to be
336 Perl_hv_exists_ent(pTHX_ HV *hv, SV *keysv, U32 hash)
338 return hv_fetch_common(hv, keysv, NULL, 0, 0, HV_FETCH_ISEXISTS, 0, hash)
342 /* returns an HE * structure with the all fields set */
343 /* note that hent_val will be a mortal sv for MAGICAL hashes */
345 =for apidoc hv_fetch_ent
347 Returns the hash entry which corresponds to the specified key in the hash.
348 C<hash> must be a valid precomputed hash number for the given C<key>, or 0
349 if you want the function to compute it. IF C<lval> is set then the fetch
350 will be part of a store. Make sure the return value is non-null before
351 accessing it. The return value when C<tb> is a tied hash is a pointer to a
352 static location, so be sure to make a copy of the structure if you need to
355 See L<perlguts/"Understanding the Magic of Tied Hashes and Arrays"> for more
356 information on how to use this function on tied hashes.
362 Perl_hv_fetch_ent(pTHX_ HV *hv, SV *keysv, I32 lval, register U32 hash)
364 return hv_fetch_common(hv, keysv, NULL, 0, 0,
365 (lval ? HV_FETCH_LVALUE : 0), Nullsv, hash);
369 S_hv_fetch_common(pTHX_ HV *hv, SV *keysv, const char *key, STRLEN klen,
370 int flags, int action, SV *val, register U32 hash)
384 if (flags & HVhek_FREEKEY)
386 key = SvPV(keysv, klen);
388 is_utf8 = (SvUTF8(keysv) != 0);
390 is_utf8 = ((flags & HVhek_UTF8) ? TRUE : FALSE);
393 xhv = (XPVHV*)SvANY(hv);
395 if (SvRMAGICAL(hv) && !(action & (HV_FETCH_ISSTORE|HV_FETCH_ISEXISTS)))
397 if (mg_find((SV*)hv, PERL_MAGIC_tied) || SvGMAGICAL((SV*)hv)) {
400 /* XXX should be able to skimp on the HE/HEK here when
401 HV_FETCH_JUST_SV is true. */
404 keysv = newSVpvn(key, klen);
409 keysv = newSVsv(keysv);
411 mg_copy((SV*)hv, sv, (char *)keysv, HEf_SVKEY);
413 /* grab a fake HE/HEK pair from the pool or make a new one */
414 entry = PL_hv_fetch_ent_mh;
416 PL_hv_fetch_ent_mh = HeNEXT(entry);
420 New(54, k, HEK_BASESIZE + sizeof(SV*), char);
421 HeKEY_hek(entry) = (HEK*)k;
423 HeNEXT(entry) = Nullhe;
424 HeSVKEY_set(entry, keysv);
426 sv_upgrade(sv, SVt_PVLV);
428 /* so we can free entry when freeing sv */
429 LvTARG(sv) = (SV*)entry;
431 /* XXX remove at some point? */
432 if (flags & HVhek_FREEKEY)
437 #ifdef ENV_IS_CASELESS
438 else if (mg_find((SV*)hv, PERL_MAGIC_env)) {
440 for (i = 0; i < klen; ++i)
441 if (isLOWER(key[i])) {
442 const char *keysave = key;
443 /* Will need to free this, so set FREEKEY flag
444 on call to hv_fetch_common. */
445 key = savepvn(key,klen);
446 key = (const char*)strupr((char*)key);
448 if (flags & HVhek_FREEKEY)
451 /* This isn't strictly the same as the old hv_fetch
452 magic, which made a call to hv_fetch, followed
453 by a call to hv_store if that failed and lvalue
455 Which I believe could have been done by simply
456 passing the lvalue through to the first hv_fetch.
457 So I will do that here. */
458 return hv_fetch_common(hv, Nullsv, key, klen,
465 else if (SvRMAGICAL(hv) && (action & HV_FETCH_ISEXISTS)) {
466 if (mg_find((SV*)hv, PERL_MAGIC_tied) || SvGMAGICAL((SV*)hv)) {
468 /* I don't understand why hv_exists_ent has svret and sv,
469 whereas hv_exists only had one. */
470 svret = sv_newmortal();
473 if (keysv || is_utf8) {
475 keysv = newSVpvn(key, klen);
478 keysv = newSVsv(keysv);
480 mg_copy((SV*)hv, sv, (char *)sv_2mortal(keysv), HEf_SVKEY);
482 mg_copy((SV*)hv, sv, key, klen);
484 if (flags & HVhek_FREEKEY)
486 magic_existspack(svret, mg_find(sv, PERL_MAGIC_tiedelem));
487 /* This cast somewhat evil, but I'm merely using NULL/
488 not NULL to return the boolean exists.
489 And I know hv is not NULL. */
490 return SvTRUE(svret) ? (HE *)hv : NULL;
492 #ifdef ENV_IS_CASELESS
493 else if (mg_find((SV*)hv, PERL_MAGIC_env)) {
494 /* XXX This code isn't UTF8 clean. */
495 const char *keysave = key;
496 /* Will need to free this, so set FREEKEY flag. */
497 key = savepvn(key,klen);
498 key = (const char*)strupr((char*)key);
502 if (flags & HVhek_FREEKEY) {
505 flags |= HVhek_FREEKEY;
509 else if (action & HV_FETCH_ISSTORE) {
512 hv_magic_check (hv, &needs_copy, &needs_store);
514 bool save_taint = PL_tainted;
515 if (keysv || is_utf8) {
517 keysv = newSVpvn(key, klen);
521 PL_tainted = SvTAINTED(keysv);
522 keysv = sv_2mortal(newSVsv(keysv));
523 mg_copy((SV*)hv, val, (char*)keysv, HEf_SVKEY);
525 mg_copy((SV*)hv, val, key, klen);
528 TAINT_IF(save_taint);
529 if (!xhv->xhv_array /* !HvARRAY(hv) */ && !needs_store) {
530 if (flags & HVhek_FREEKEY)
534 #ifdef ENV_IS_CASELESS
535 else if (mg_find((SV*)hv, PERL_MAGIC_env)) {
536 /* XXX This code isn't UTF8 clean. */
537 const char *keysave = key;
538 /* Will need to free this, so set FREEKEY flag. */
539 key = savepvn(key,klen);
540 key = (const char*)strupr((char*)key);
544 if (flags & HVhek_FREEKEY) {
547 flags |= HVhek_FREEKEY;
554 if (!xhv->xhv_array /* !HvARRAY(hv) */) {
555 if ((action & (HV_FETCH_LVALUE | HV_FETCH_ISSTORE))
556 #ifdef DYNAMIC_ENV_FETCH /* if it's an %ENV lookup, we may get it on the fly */
557 || (SvRMAGICAL((SV*)hv) && mg_find((SV*)hv, PERL_MAGIC_env))
560 Newz(503, xhv->xhv_array /* HvARRAY(hv) */,
561 PERL_HV_ARRAY_ALLOC_BYTES(xhv->xhv_max+1 /* HvMAX(hv)+1 */),
563 #ifdef DYNAMIC_ENV_FETCH
564 else if (action & HV_FETCH_ISEXISTS) {
565 /* for an %ENV exists, if we do an insert it's by a recursive
566 store call, so avoid creating HvARRAY(hv) right now. */
570 /* XXX remove at some point? */
571 if (flags & HVhek_FREEKEY)
579 const char *keysave = key;
580 key = (char*)bytes_from_utf8((U8*)key, &klen, &is_utf8);
584 flags &= ~HVhek_UTF8;
585 if (key != keysave) {
586 if (flags & HVhek_FREEKEY)
588 flags |= HVhek_WASUTF8 | HVhek_FREEKEY;
593 PERL_HASH_INTERNAL(hash, key, klen);
594 /* We don't have a pointer to the hv, so we have to replicate the
595 flag into every HEK, so that hv_iterkeysv can see it. */
596 /* And yes, you do need this even though you are not "storing" because
597 you can flip the flags below if doing an lval lookup. (And that
598 was put in to give the semantics Andreas was expecting.) */
599 flags |= HVhek_REHASH;
601 if (keysv && (SvIsCOW_shared_hash(keysv))) {
604 PERL_HASH(hash, key, klen);
608 masked_flags = (flags & HVhek_MASK);
611 #ifdef DYNAMIC_ENV_FETCH
612 if (!xhv->xhv_array /* !HvARRAY(hv) */) entry = Null(HE*);
616 /* entry = (HvARRAY(hv))[hash & (I32) HvMAX(hv)]; */
617 entry = ((HE**)xhv->xhv_array)[hash & (I32) xhv->xhv_max];
619 for (; entry; ++n_links, entry = HeNEXT(entry)) {
620 if (HeHASH(entry) != hash) /* strings can't be equal */
622 if (HeKLEN(entry) != (I32)klen)
624 if (HeKEY(entry) != key && memNE(HeKEY(entry),key,klen)) /* is this it? */
626 if ((HeKFLAGS(entry) ^ masked_flags) & HVhek_UTF8)
629 if (action & (HV_FETCH_LVALUE|HV_FETCH_ISSTORE)) {
630 if (HeKFLAGS(entry) != masked_flags) {
631 /* We match if HVhek_UTF8 bit in our flags and hash key's
632 match. But if entry was set previously with HVhek_WASUTF8
633 and key now doesn't (or vice versa) then we should change
634 the key's flag, as this is assignment. */
635 if (HvSHAREKEYS(hv)) {
636 /* Need to swap the key we have for a key with the flags we
637 need. As keys are shared we can't just write to the
638 flag, so we share the new one, unshare the old one. */
639 HEK *new_hek = share_hek_flags(key, klen, hash,
641 unshare_hek (HeKEY_hek(entry));
642 HeKEY_hek(entry) = new_hek;
645 HeKFLAGS(entry) = masked_flags;
646 if (masked_flags & HVhek_ENABLEHVKFLAGS)
649 if (HeVAL(entry) == &PL_sv_placeholder) {
650 /* yes, can store into placeholder slot */
651 if (action & HV_FETCH_LVALUE) {
653 /* This preserves behaviour with the old hv_fetch
654 implementation which at this point would bail out
655 with a break; (at "if we find a placeholder, we
656 pretend we haven't found anything")
658 That break mean that if a placeholder were found, it
659 caused a call into hv_store, which in turn would
660 check magic, and if there is no magic end up pretty
661 much back at this point (in hv_store's code). */
664 /* LVAL fetch which actaully needs a store. */
666 xhv->xhv_placeholders--;
669 if (val != &PL_sv_placeholder)
670 xhv->xhv_placeholders--;
673 } else if (action & HV_FETCH_ISSTORE) {
674 SvREFCNT_dec(HeVAL(entry));
677 } else if (HeVAL(entry) == &PL_sv_placeholder) {
678 /* if we find a placeholder, we pretend we haven't found
682 if (flags & HVhek_FREEKEY)
686 #ifdef DYNAMIC_ENV_FETCH /* %ENV lookup? If so, try to fetch the value now */
687 if (!(action & HV_FETCH_ISSTORE)
688 && SvRMAGICAL((SV*)hv) && mg_find((SV*)hv, PERL_MAGIC_env)) {
690 char *env = PerlEnv_ENVgetenv_len(key,&len);
692 sv = newSVpvn(env,len);
694 return hv_fetch_common(hv,keysv,key,klen,flags,HV_FETCH_ISSTORE,sv,
700 if (!entry && SvREADONLY(hv) && !(action & HV_FETCH_ISEXISTS)) {
701 S_hv_notallowed(aTHX_ flags, key, klen,
702 "access disallowed key '%"SVf"' in"
705 if (!(action & (HV_FETCH_LVALUE|HV_FETCH_ISSTORE))) {
706 /* Not doing some form of store, so return failure. */
707 if (flags & HVhek_FREEKEY)
711 if (action & HV_FETCH_LVALUE) {
714 /* At this point the old hv_fetch code would call to hv_store,
715 which in turn might do some tied magic. So we need to make that
716 magic check happen. */
717 /* gonna assign to this, so it better be there */
718 return hv_fetch_common(hv, keysv, key, klen, flags,
719 HV_FETCH_ISSTORE, val, hash);
720 /* XXX Surely that could leak if the fetch-was-store fails?
721 Just like the hv_fetch. */
725 /* Welcome to hv_store... */
727 if (!xhv->xhv_array) {
728 /* Not sure if we can get here. I think the only case of oentry being
729 NULL is for %ENV with dynamic env fetch. But that should disappear
730 with magic in the previous code. */
731 Newz(503, xhv->xhv_array /* HvARRAY(hv) */,
732 PERL_HV_ARRAY_ALLOC_BYTES(xhv->xhv_max+1 /* HvMAX(hv)+1 */),
736 oentry = &((HE**)xhv->xhv_array)[hash & (I32) xhv->xhv_max];
739 /* share_hek_flags will do the free for us. This might be considered
742 HeKEY_hek(entry) = share_hek_flags(key, klen, hash, flags);
743 else /* gotta do the real thing */
744 HeKEY_hek(entry) = save_hek_flags(key, klen, hash, flags);
746 HeNEXT(entry) = *oentry;
749 if (val == &PL_sv_placeholder)
750 xhv->xhv_placeholders++;
751 if (masked_flags & HVhek_ENABLEHVKFLAGS)
754 xhv->xhv_keys++; /* HvKEYS(hv)++ */
755 if (!n_links) { /* initial entry? */
756 xhv->xhv_fill++; /* HvFILL(hv)++ */
757 } else if ((xhv->xhv_keys > (IV)xhv->xhv_max)
758 || ((n_links > HV_MAX_LENGTH_BEFORE_SPLIT) && !HvREHASH(hv))) {
759 /* Use only the old HvKEYS(hv) > HvMAX(hv) condition to limit bucket
760 splits on a rehashed hash, as we're not going to split it again,
761 and if someone is lucky (evil) enough to get all the keys in one
762 list they could exhaust our memory as we repeatedly double the
763 number of buckets on every entry. Linear search feels a less worse
772 S_hv_magic_check(pTHX_ HV *hv, bool *needs_copy, bool *needs_store)
774 MAGIC *mg = SvMAGIC(hv);
778 if (isUPPER(mg->mg_type)) {
780 switch (mg->mg_type) {
781 case PERL_MAGIC_tied:
783 *needs_store = FALSE;
786 mg = mg->mg_moremagic;
791 =for apidoc hv_scalar
793 Evaluates the hash in scalar context and returns the result. Handles magic when the hash is tied.
799 Perl_hv_scalar(pTHX_ HV *hv)
804 if ((SvRMAGICAL(hv) && (mg = mg_find((SV*)hv, PERL_MAGIC_tied)))) {
805 sv = magic_scalarpack(hv, mg);
811 Perl_sv_setpvf(aTHX_ sv, "%ld/%ld",
812 (long)HvFILL(hv), (long)HvMAX(hv) + 1);
820 =for apidoc hv_delete
822 Deletes a key/value pair in the hash. The value SV is removed from the
823 hash and returned to the caller. The C<klen> is the length of the key.
824 The C<flags> value will normally be zero; if set to G_DISCARD then NULL
831 Perl_hv_delete(pTHX_ HV *hv, const char *key, I32 klen_i32, I32 flags)
838 k_flags |= HVhek_UTF8;
842 return hv_delete_common(hv, NULL, key, klen, k_flags, flags, 0);
846 =for apidoc hv_delete_ent
848 Deletes a key/value pair in the hash. The value SV is removed from the
849 hash and returned to the caller. The C<flags> value will normally be zero;
850 if set to G_DISCARD then NULL will be returned. C<hash> can be a valid
851 precomputed hash value, or 0 to ask for it to be computed.
857 Perl_hv_delete_ent(pTHX_ HV *hv, SV *keysv, I32 flags, U32 hash)
859 return hv_delete_common(hv, keysv, NULL, 0, 0, flags, hash);
863 S_hv_delete_common(pTHX_ HV *hv, SV *keysv, const char *key, STRLEN klen,
864 int k_flags, I32 d_flags, U32 hash)
869 register HE **oentry;
878 if (k_flags & HVhek_FREEKEY)
880 key = SvPV(keysv, klen);
882 is_utf8 = (SvUTF8(keysv) != 0);
884 is_utf8 = ((k_flags & HVhek_UTF8) ? TRUE : FALSE);
887 if (SvRMAGICAL(hv)) {
890 hv_magic_check (hv, &needs_copy, &needs_store);
893 entry = hv_fetch_common(hv, keysv, key, klen,
894 k_flags & ~HVhek_FREEKEY, HV_FETCH_LVALUE,
896 sv = entry ? HeVAL(entry) : NULL;
902 if (mg_find(sv, PERL_MAGIC_tiedelem)) {
903 /* No longer an element */
904 sv_unmagic(sv, PERL_MAGIC_tiedelem);
907 return Nullsv; /* element cannot be deleted */
909 #ifdef ENV_IS_CASELESS
910 else if (mg_find((SV*)hv, PERL_MAGIC_env)) {
911 /* XXX This code isn't UTF8 clean. */
912 keysv = sv_2mortal(newSVpvn(key,klen));
913 if (k_flags & HVhek_FREEKEY) {
916 key = strupr(SvPVX(keysv));
925 xhv = (XPVHV*)SvANY(hv);
926 if (!xhv->xhv_array /* !HvARRAY(hv) */)
930 const char *keysave = key;
931 key = (char*)bytes_from_utf8((U8*)key, &klen, &is_utf8);
934 k_flags |= HVhek_UTF8;
936 k_flags &= ~HVhek_UTF8;
937 if (key != keysave) {
938 if (k_flags & HVhek_FREEKEY) {
939 /* This shouldn't happen if our caller does what we expect,
940 but strictly the API allows it. */
943 k_flags |= HVhek_WASUTF8 | HVhek_FREEKEY;
945 HvHASKFLAGS_on((SV*)hv);
949 PERL_HASH_INTERNAL(hash, key, klen);
951 if (keysv && (SvIsCOW_shared_hash(keysv))) {
954 PERL_HASH(hash, key, klen);
956 PERL_HASH(hash, key, klen);
959 masked_flags = (k_flags & HVhek_MASK);
961 /* oentry = &(HvARRAY(hv))[hash & (I32) HvMAX(hv)]; */
962 oentry = &((HE**)xhv->xhv_array)[hash & (I32) xhv->xhv_max];
965 for (; entry; i=0, oentry = &HeNEXT(entry), entry = *oentry) {
966 if (HeHASH(entry) != hash) /* strings can't be equal */
968 if (HeKLEN(entry) != (I32)klen)
970 if (HeKEY(entry) != key && memNE(HeKEY(entry),key,klen)) /* is this it? */
972 if ((HeKFLAGS(entry) ^ masked_flags) & HVhek_UTF8)
974 if (k_flags & HVhek_FREEKEY)
977 /* if placeholder is here, it's already been deleted.... */
978 if (HeVAL(entry) == &PL_sv_placeholder)
981 return Nullsv; /* if still SvREADONLY, leave it deleted. */
983 /* okay, really delete the placeholder. */
984 *oentry = HeNEXT(entry);
986 xhv->xhv_fill--; /* HvFILL(hv)-- */
987 if (entry == xhv->xhv_eiter /* HvEITER(hv) */)
990 hv_free_ent(hv, entry);
991 xhv->xhv_keys--; /* HvKEYS(hv)-- */
992 if (xhv->xhv_keys == 0)
994 xhv->xhv_placeholders--;
997 else if (SvREADONLY(hv) && HeVAL(entry) && SvREADONLY(HeVAL(entry))) {
998 S_hv_notallowed(aTHX_ k_flags, key, klen,
999 "delete readonly key '%"SVf"' from"
1003 if (d_flags & G_DISCARD)
1006 sv = sv_2mortal(HeVAL(entry));
1007 HeVAL(entry) = &PL_sv_placeholder;
1011 * If a restricted hash, rather than really deleting the entry, put
1012 * a placeholder there. This marks the key as being "approved", so
1013 * we can still access via not-really-existing key without raising
1016 if (SvREADONLY(hv)) {
1017 HeVAL(entry) = &PL_sv_placeholder;
1018 /* We'll be saving this slot, so the number of allocated keys
1019 * doesn't go down, but the number placeholders goes up */
1020 xhv->xhv_placeholders++; /* HvPLACEHOLDERS(hv)++ */
1022 *oentry = HeNEXT(entry);
1024 xhv->xhv_fill--; /* HvFILL(hv)-- */
1025 if (entry == xhv->xhv_eiter /* HvEITER(hv) */)
1028 hv_free_ent(hv, entry);
1029 xhv->xhv_keys--; /* HvKEYS(hv)-- */
1030 if (xhv->xhv_keys == 0)
1031 HvHASKFLAGS_off(hv);
1035 if (SvREADONLY(hv)) {
1036 S_hv_notallowed(aTHX_ k_flags, key, klen,
1037 "delete disallowed key '%"SVf"' from"
1041 if (k_flags & HVhek_FREEKEY)
1047 S_hsplit(pTHX_ HV *hv)
1049 register XPVHV* xhv = (XPVHV*)SvANY(hv);
1050 I32 oldsize = (I32) xhv->xhv_max+1; /* HvMAX(hv)+1 (sick) */
1051 register I32 newsize = oldsize * 2;
1053 register char *a = xhv->xhv_array; /* HvARRAY(hv) */
1057 register HE **oentry;
1058 int longest_chain = 0;
1062 #if defined(STRANGE_MALLOC) || defined(MYMALLOC)
1063 Renew(a, PERL_HV_ARRAY_ALLOC_BYTES(newsize), char);
1069 New(2, a, PERL_HV_ARRAY_ALLOC_BYTES(newsize), char);
1074 Copy(xhv->xhv_array /* HvARRAY(hv) */, a, oldsize * sizeof(HE*), char);
1075 if (oldsize >= 64) {
1076 offer_nice_chunk(xhv->xhv_array /* HvARRAY(hv) */,
1077 PERL_HV_ARRAY_ALLOC_BYTES(oldsize));
1080 Safefree(xhv->xhv_array /* HvARRAY(hv) */);
1084 Zero(&a[oldsize * sizeof(HE*)], (newsize-oldsize) * sizeof(HE*), char); /* zero 2nd half*/
1085 xhv->xhv_max = --newsize; /* HvMAX(hv) = --newsize */
1086 xhv->xhv_array = a; /* HvARRAY(hv) = a */
1089 for (i=0; i<oldsize; i++,aep++) {
1090 int left_length = 0;
1091 int right_length = 0;
1093 if (!*aep) /* non-existent */
1096 for (oentry = aep, entry = *aep; entry; entry = *oentry) {
1097 if ((HeHASH(entry) & newsize) != (U32)i) {
1098 *oentry = HeNEXT(entry);
1099 HeNEXT(entry) = *bep;
1101 xhv->xhv_fill++; /* HvFILL(hv)++ */
1107 oentry = &HeNEXT(entry);
1111 if (!*aep) /* everything moved */
1112 xhv->xhv_fill--; /* HvFILL(hv)-- */
1113 /* I think we don't actually need to keep track of the longest length,
1114 merely flag if anything is too long. But for the moment while
1115 developing this code I'll track it. */
1116 if (left_length > longest_chain)
1117 longest_chain = left_length;
1118 if (right_length > longest_chain)
1119 longest_chain = right_length;
1123 /* Pick your policy for "hashing isn't working" here: */
1124 if (longest_chain <= HV_MAX_LENGTH_BEFORE_SPLIT /* split worked? */
1129 if (hv == PL_strtab) {
1130 /* Urg. Someone is doing something nasty to the string table.
1135 /* Awooga. Awooga. Pathological data. */
1136 /*PerlIO_printf(PerlIO_stderr(), "%p %d of %d with %d/%d buckets\n", hv,
1137 longest_chain, HvTOTALKEYS(hv), HvFILL(hv), 1+HvMAX(hv));*/
1140 Newz(2, a, PERL_HV_ARRAY_ALLOC_BYTES(newsize), char);
1141 was_shared = HvSHAREKEYS(hv);
1144 HvSHAREKEYS_off(hv);
1147 aep = (HE **) xhv->xhv_array;
1149 for (i=0; i<newsize; i++,aep++) {
1152 /* We're going to trash this HE's next pointer when we chain it
1153 into the new hash below, so store where we go next. */
1154 HE *next = HeNEXT(entry);
1158 PERL_HASH_INTERNAL(hash, HeKEY(entry), HeKLEN(entry));
1163 = save_hek_flags(HeKEY(entry), HeKLEN(entry),
1164 hash, HeKFLAGS(entry));
1165 unshare_hek (HeKEY_hek(entry));
1166 HeKEY_hek(entry) = new_hek;
1168 /* Not shared, so simply write the new hash in. */
1169 HeHASH(entry) = hash;
1171 /*PerlIO_printf(PerlIO_stderr(), "%d ", HeKFLAGS(entry));*/
1172 HEK_REHASH_on(HeKEY_hek(entry));
1173 /*PerlIO_printf(PerlIO_stderr(), "%d\n", HeKFLAGS(entry));*/
1175 /* Copy oentry to the correct new chain. */
1176 bep = ((HE**)a) + (hash & (I32) xhv->xhv_max);
1178 xhv->xhv_fill++; /* HvFILL(hv)++ */
1179 HeNEXT(entry) = *bep;
1185 Safefree (xhv->xhv_array);
1186 xhv->xhv_array = a; /* HvARRAY(hv) = a */
1190 Perl_hv_ksplit(pTHX_ HV *hv, IV newmax)
1192 register XPVHV* xhv = (XPVHV*)SvANY(hv);
1193 I32 oldsize = (I32) xhv->xhv_max+1; /* HvMAX(hv)+1 (sick) */
1194 register I32 newsize;
1200 register HE **oentry;
1202 newsize = (I32) newmax; /* possible truncation here */
1203 if (newsize != newmax || newmax <= oldsize)
1205 while ((newsize & (1 + ~newsize)) != newsize) {
1206 newsize &= ~(newsize & (1 + ~newsize)); /* get proper power of 2 */
1208 if (newsize < newmax)
1210 if (newsize < newmax)
1211 return; /* overflow detection */
1213 a = xhv->xhv_array; /* HvARRAY(hv) */
1216 #if defined(STRANGE_MALLOC) || defined(MYMALLOC)
1217 Renew(a, PERL_HV_ARRAY_ALLOC_BYTES(newsize), char);
1223 New(2, a, PERL_HV_ARRAY_ALLOC_BYTES(newsize), char);
1228 Copy(xhv->xhv_array /* HvARRAY(hv) */, a, oldsize * sizeof(HE*), char);
1229 if (oldsize >= 64) {
1230 offer_nice_chunk(xhv->xhv_array /* HvARRAY(hv) */,
1231 PERL_HV_ARRAY_ALLOC_BYTES(oldsize));
1234 Safefree(xhv->xhv_array /* HvARRAY(hv) */);
1237 Zero(&a[oldsize * sizeof(HE*)], (newsize-oldsize) * sizeof(HE*), char); /* zero 2nd half*/
1240 Newz(0, a, PERL_HV_ARRAY_ALLOC_BYTES(newsize), char);
1242 xhv->xhv_max = --newsize; /* HvMAX(hv) = --newsize */
1243 xhv->xhv_array = a; /* HvARRAY(hv) = a */
1244 if (!xhv->xhv_fill /* !HvFILL(hv) */) /* skip rest if no entries */
1248 for (i=0; i<oldsize; i++,aep++) {
1249 if (!*aep) /* non-existent */
1251 for (oentry = aep, entry = *aep; entry; entry = *oentry) {
1252 if ((j = (HeHASH(entry) & newsize)) != i) {
1254 *oentry = HeNEXT(entry);
1255 if (!(HeNEXT(entry) = aep[j]))
1256 xhv->xhv_fill++; /* HvFILL(hv)++ */
1261 oentry = &HeNEXT(entry);
1263 if (!*aep) /* everything moved */
1264 xhv->xhv_fill--; /* HvFILL(hv)-- */
1271 Creates a new HV. The reference count is set to 1.
1280 register XPVHV* xhv;
1282 hv = (HV*)NEWSV(502,0);
1283 sv_upgrade((SV *)hv, SVt_PVHV);
1284 xhv = (XPVHV*)SvANY(hv);
1287 #ifndef NODEFAULT_SHAREKEYS
1288 HvSHAREKEYS_on(hv); /* key-sharing on by default */
1291 xhv->xhv_max = 7; /* HvMAX(hv) = 7 (start with 8 buckets) */
1292 xhv->xhv_fill = 0; /* HvFILL(hv) = 0 */
1293 xhv->xhv_pmroot = 0; /* HvPMROOT(hv) = 0 */
1294 (void)hv_iterinit(hv); /* so each() will start off right */
1299 Perl_newHVhv(pTHX_ HV *ohv)
1302 STRLEN hv_max, hv_fill;
1304 if (!ohv || (hv_fill = HvFILL(ohv)) == 0)
1306 hv_max = HvMAX(ohv);
1308 if (!SvMAGICAL((SV *)ohv)) {
1309 /* It's an ordinary hash, so copy it fast. AMS 20010804 */
1311 bool shared = !!HvSHAREKEYS(ohv);
1312 HE **ents, **oents = (HE **)HvARRAY(ohv);
1314 New(0, a, PERL_HV_ARRAY_ALLOC_BYTES(hv_max+1), char);
1317 /* In each bucket... */
1318 for (i = 0; i <= hv_max; i++) {
1319 HE *prev = NULL, *ent = NULL, *oent = oents[i];
1326 /* Copy the linked list of entries. */
1327 for (oent = oents[i]; oent; oent = HeNEXT(oent)) {
1328 U32 hash = HeHASH(oent);
1329 char *key = HeKEY(oent);
1330 STRLEN len = HeKLEN(oent);
1331 int flags = HeKFLAGS(oent);
1334 HeVAL(ent) = newSVsv(HeVAL(oent));
1336 = shared ? share_hek_flags(key, len, hash, flags)
1337 : save_hek_flags(key, len, hash, flags);
1348 HvFILL(hv) = hv_fill;
1349 HvTOTALKEYS(hv) = HvTOTALKEYS(ohv);
1353 /* Iterate over ohv, copying keys and values one at a time. */
1355 I32 riter = HvRITER(ohv);
1356 HE *eiter = HvEITER(ohv);
1358 /* Can we use fewer buckets? (hv_max is always 2^n-1) */
1359 while (hv_max && hv_max + 1 >= hv_fill * 2)
1360 hv_max = hv_max / 2;
1364 while ((entry = hv_iternext_flags(ohv, 0))) {
1365 hv_store_flags(hv, HeKEY(entry), HeKLEN(entry),
1366 newSVsv(HeVAL(entry)), HeHASH(entry),
1369 HvRITER(ohv) = riter;
1370 HvEITER(ohv) = eiter;
1377 Perl_hv_free_ent(pTHX_ HV *hv, register HE *entry)
1384 if (val && isGV(val) && GvCVu(val) && HvNAME(hv))
1385 PL_sub_generation++; /* may be deletion of method from stash */
1387 if (HeKLEN(entry) == HEf_SVKEY) {
1388 SvREFCNT_dec(HeKEY_sv(entry));
1389 Safefree(HeKEY_hek(entry));
1391 else if (HvSHAREKEYS(hv))
1392 unshare_hek(HeKEY_hek(entry));
1394 Safefree(HeKEY_hek(entry));
1399 Perl_hv_delayfree_ent(pTHX_ HV *hv, register HE *entry)
1403 if (isGV(HeVAL(entry)) && GvCVu(HeVAL(entry)) && HvNAME(hv))
1404 PL_sub_generation++; /* may be deletion of method from stash */
1405 sv_2mortal(HeVAL(entry)); /* free between statements */
1406 if (HeKLEN(entry) == HEf_SVKEY) {
1407 sv_2mortal(HeKEY_sv(entry));
1408 Safefree(HeKEY_hek(entry));
1410 else if (HvSHAREKEYS(hv))
1411 unshare_hek(HeKEY_hek(entry));
1413 Safefree(HeKEY_hek(entry));
1418 =for apidoc hv_clear
1420 Clears a hash, making it empty.
1426 Perl_hv_clear(pTHX_ HV *hv)
1428 register XPVHV* xhv;
1432 DEBUG_A(Perl_hv_assert(aTHX_ hv));
1434 xhv = (XPVHV*)SvANY(hv);
1436 if (SvREADONLY(hv) && xhv->xhv_array != NULL) {
1437 /* restricted hash: convert all keys to placeholders */
1440 for (i = 0; i <= (I32) xhv->xhv_max; i++) {
1441 entry = ((HE**)xhv->xhv_array)[i];
1442 for (; entry; entry = HeNEXT(entry)) {
1443 /* not already placeholder */
1444 if (HeVAL(entry) != &PL_sv_placeholder) {
1445 if (HeVAL(entry) && SvREADONLY(HeVAL(entry))) {
1446 SV* keysv = hv_iterkeysv(entry);
1448 "Attempt to delete readonly key '%"SVf"' from a restricted hash",
1451 SvREFCNT_dec(HeVAL(entry));
1452 HeVAL(entry) = &PL_sv_placeholder;
1453 xhv->xhv_placeholders++; /* HvPLACEHOLDERS(hv)++ */
1461 xhv->xhv_placeholders = 0; /* HvPLACEHOLDERS(hv) = 0 */
1462 if (xhv->xhv_array /* HvARRAY(hv) */)
1463 (void)memzero(xhv->xhv_array /* HvARRAY(hv) */,
1464 (xhv->xhv_max+1 /* HvMAX(hv)+1 */) * sizeof(HE*));
1469 HvHASKFLAGS_off(hv);
1476 =for apidoc hv_clear_placeholders
1478 Clears any placeholders from a hash. If a restricted hash has any of its keys
1479 marked as readonly and the key is subsequently deleted, the key is not actually
1480 deleted but is marked by assigning it a value of &PL_sv_placeholder. This tags
1481 it so it will be ignored by future operations such as iterating over the hash,
1482 but will still allow the hash to have a value reaasigned to the key at some
1483 future point. This function clears any such placeholder keys from the hash.
1484 See Hash::Util::lock_keys() for an example of its use.
1490 Perl_hv_clear_placeholders(pTHX_ HV *hv)
1493 items = (I32)HvPLACEHOLDERS(hv);
1496 I32 riter = HvRITER(hv);
1497 HE *eiter = HvEITER(hv);
1499 /* This may look suboptimal with the items *after* the iternext, but
1500 it's quite deliberate. We only get here with items==0 if we've
1501 just deleted the last placeholder in the hash. If we've just done
1502 that then it means that the hash is in lazy delete mode, and the
1503 HE is now only referenced in our iterator. If we just quit the loop
1504 and discarded our iterator then the HE leaks. So we do the && the
1505 other way to ensure iternext is called just one more time, which
1506 has the side effect of triggering the lazy delete. */
1507 while ((entry = hv_iternext_flags(hv, HV_ITERNEXT_WANTPLACEHOLDERS))
1509 SV *val = hv_iterval(hv, entry);
1511 if (val == &PL_sv_placeholder) {
1513 /* It seems that I have to go back in the front of the hash
1514 API to delete a hash, even though I have a HE structure
1515 pointing to the very entry I want to delete, and could hold
1516 onto the previous HE that points to it. And it's easier to
1517 go in with SVs as I can then specify the precomputed hash,
1518 and don't have fun and games with utf8 keys. */
1519 SV *key = hv_iterkeysv(entry);
1521 hv_delete_ent (hv, key, G_DISCARD, HeHASH(entry));
1525 HvRITER(hv) = riter;
1526 HvEITER(hv) = eiter;
1531 S_hfreeentries(pTHX_ HV *hv)
1533 register HE **array;
1535 register HE *oentry = Null(HE*);
1546 array = HvARRAY(hv);
1547 /* make everyone else think the array is empty, so that the destructors
1548 * called for freed entries can't recusively mess with us */
1549 HvARRAY(hv) = Null(HE**);
1551 ((XPVHV*) SvANY(hv))->xhv_keys = 0;
1557 entry = HeNEXT(entry);
1558 hv_free_ent(hv, oentry);
1563 entry = array[riter];
1566 HvARRAY(hv) = array;
1567 (void)hv_iterinit(hv);
1571 =for apidoc hv_undef
1579 Perl_hv_undef(pTHX_ HV *hv)
1581 register XPVHV* xhv;
1584 DEBUG_A(Perl_hv_assert(aTHX_ hv));
1585 xhv = (XPVHV*)SvANY(hv);
1587 Safefree(xhv->xhv_array /* HvARRAY(hv) */);
1590 hv_delete(PL_stashcache, HvNAME(hv), strlen(HvNAME(hv)), G_DISCARD);
1591 Safefree(HvNAME(hv));
1594 xhv->xhv_max = 7; /* HvMAX(hv) = 7 (it's a normal hash) */
1595 xhv->xhv_array = 0; /* HvARRAY(hv) = 0 */
1596 xhv->xhv_placeholders = 0; /* HvPLACEHOLDERS(hv) = 0 */
1603 =for apidoc hv_iterinit
1605 Prepares a starting point to traverse a hash table. Returns the number of
1606 keys in the hash (i.e. the same as C<HvKEYS(tb)>). The return value is
1607 currently only meaningful for hashes without tie magic.
1609 NOTE: Before version 5.004_65, C<hv_iterinit> used to return the number of
1610 hash buckets that happen to be in use. If you still need that esoteric
1611 value, you can get it through the macro C<HvFILL(tb)>.
1618 Perl_hv_iterinit(pTHX_ HV *hv)
1620 register XPVHV* xhv;
1624 Perl_croak(aTHX_ "Bad hash");
1625 xhv = (XPVHV*)SvANY(hv);
1626 entry = xhv->xhv_eiter; /* HvEITER(hv) */
1627 if (entry && HvLAZYDEL(hv)) { /* was deleted earlier? */
1629 hv_free_ent(hv, entry);
1631 xhv->xhv_riter = -1; /* HvRITER(hv) = -1 */
1632 xhv->xhv_eiter = Null(HE*); /* HvEITER(hv) = Null(HE*) */
1633 /* used to be xhv->xhv_fill before 5.004_65 */
1634 return XHvTOTALKEYS(xhv);
1637 =for apidoc hv_iternext
1639 Returns entries from a hash iterator. See C<hv_iterinit>.
1641 You may call C<hv_delete> or C<hv_delete_ent> on the hash entry that the
1642 iterator currently points to, without losing your place or invalidating your
1643 iterator. Note that in this case the current entry is deleted from the hash
1644 with your iterator holding the last reference to it. Your iterator is flagged
1645 to free the entry on the next call to C<hv_iternext>, so you must not discard
1646 your iterator immediately else the entry will leak - call C<hv_iternext> to
1647 trigger the resource deallocation.
1653 Perl_hv_iternext(pTHX_ HV *hv)
1655 return hv_iternext_flags(hv, 0);
1659 =for apidoc hv_iternext_flags
1661 Returns entries from a hash iterator. See C<hv_iterinit> and C<hv_iternext>.
1662 The C<flags> value will normally be zero; if HV_ITERNEXT_WANTPLACEHOLDERS is
1663 set the placeholders keys (for restricted hashes) will be returned in addition
1664 to normal keys. By default placeholders are automatically skipped over.
1665 Currently a placeholder is implemented with a value that is
1666 C<&Perl_sv_placeholder>. Note that the implementation of placeholders and
1667 restricted hashes may change, and the implementation currently is
1668 insufficiently abstracted for any change to be tidy.
1674 Perl_hv_iternext_flags(pTHX_ HV *hv, I32 flags)
1676 register XPVHV* xhv;
1682 Perl_croak(aTHX_ "Bad hash");
1683 xhv = (XPVHV*)SvANY(hv);
1684 oldentry = entry = xhv->xhv_eiter; /* HvEITER(hv) */
1686 if ((mg = SvTIED_mg((SV*)hv, PERL_MAGIC_tied))) {
1687 SV *key = sv_newmortal();
1689 sv_setsv(key, HeSVKEY_force(entry));
1690 SvREFCNT_dec(HeSVKEY(entry)); /* get rid of previous key */
1696 /* one HE per MAGICAL hash */
1697 xhv->xhv_eiter = entry = new_HE(); /* HvEITER(hv) = new_HE() */
1699 Newz(54, k, HEK_BASESIZE + sizeof(SV*), char);
1701 HeKEY_hek(entry) = hek;
1702 HeKLEN(entry) = HEf_SVKEY;
1704 magic_nextpack((SV*) hv,mg,key);
1706 /* force key to stay around until next time */
1707 HeSVKEY_set(entry, SvREFCNT_inc(key));
1708 return entry; /* beware, hent_val is not set */
1711 SvREFCNT_dec(HeVAL(entry));
1712 Safefree(HeKEY_hek(entry));
1714 xhv->xhv_eiter = Null(HE*); /* HvEITER(hv) = Null(HE*) */
1717 #ifdef DYNAMIC_ENV_FETCH /* set up %ENV for iteration */
1718 if (!entry && SvRMAGICAL((SV*)hv) && mg_find((SV*)hv, PERL_MAGIC_env))
1722 if (!xhv->xhv_array /* !HvARRAY(hv) */)
1723 Newz(506, xhv->xhv_array /* HvARRAY(hv) */,
1724 PERL_HV_ARRAY_ALLOC_BYTES(xhv->xhv_max+1 /* HvMAX(hv)+1 */),
1726 /* At start of hash, entry is NULL. */
1729 entry = HeNEXT(entry);
1730 if (!(flags & HV_ITERNEXT_WANTPLACEHOLDERS)) {
1732 * Skip past any placeholders -- don't want to include them in
1735 while (entry && HeVAL(entry) == &PL_sv_placeholder) {
1736 entry = HeNEXT(entry);
1741 /* OK. Come to the end of the current list. Grab the next one. */
1743 xhv->xhv_riter++; /* HvRITER(hv)++ */
1744 if (xhv->xhv_riter > (I32)xhv->xhv_max /* HvRITER(hv) > HvMAX(hv) */) {
1745 /* There is no next one. End of the hash. */
1746 xhv->xhv_riter = -1; /* HvRITER(hv) = -1 */
1749 /* entry = (HvARRAY(hv))[HvRITER(hv)]; */
1750 entry = ((HE**)xhv->xhv_array)[xhv->xhv_riter];
1752 if (!(flags & HV_ITERNEXT_WANTPLACEHOLDERS)) {
1753 /* If we have an entry, but it's a placeholder, don't count it.
1755 while (entry && HeVAL(entry) == &PL_sv_placeholder)
1756 entry = HeNEXT(entry);
1758 /* Will loop again if this linked list starts NULL
1759 (for HV_ITERNEXT_WANTPLACEHOLDERS)
1760 or if we run through it and find only placeholders. */
1763 if (oldentry && HvLAZYDEL(hv)) { /* was deleted earlier? */
1765 hv_free_ent(hv, oldentry);
1768 /*if (HvREHASH(hv) && entry && !HeKREHASH(entry))
1769 PerlIO_printf(PerlIO_stderr(), "Awooga %p %p\n", hv, entry);*/
1771 xhv->xhv_eiter = entry; /* HvEITER(hv) = entry */
1776 =for apidoc hv_iterkey
1778 Returns the key from the current position of the hash iterator. See
1785 Perl_hv_iterkey(pTHX_ register HE *entry, I32 *retlen)
1787 if (HeKLEN(entry) == HEf_SVKEY) {
1789 char *p = SvPV(HeKEY_sv(entry), len);
1794 *retlen = HeKLEN(entry);
1795 return HeKEY(entry);
1799 /* unlike hv_iterval(), this always returns a mortal copy of the key */
1801 =for apidoc hv_iterkeysv
1803 Returns the key as an C<SV*> from the current position of the hash
1804 iterator. The return value will always be a mortal copy of the key. Also
1811 Perl_hv_iterkeysv(pTHX_ register HE *entry)
1813 if (HeKLEN(entry) != HEf_SVKEY) {
1814 HEK *hek = HeKEY_hek(entry);
1815 int flags = HEK_FLAGS(hek);
1818 if (flags & HVhek_WASUTF8) {
1820 Andreas would like keys he put in as utf8 to come back as utf8
1822 STRLEN utf8_len = HEK_LEN(hek);
1823 U8 *as_utf8 = bytes_to_utf8 ((U8*)HEK_KEY(hek), &utf8_len);
1825 sv = newSVpvn ((char*)as_utf8, utf8_len);
1827 Safefree (as_utf8); /* bytes_to_utf8() allocates a new string */
1828 } else if (flags & HVhek_REHASH) {
1829 /* We don't have a pointer to the hv, so we have to replicate the
1830 flag into every HEK. This hv is using custom a hasing
1831 algorithm. Hence we can't return a shared string scalar, as
1832 that would contain the (wrong) hash value, and might get passed
1833 into an hv routine with a regular hash */
1835 sv = newSVpvn (HEK_KEY(hek), HEK_LEN(hek));
1839 sv = newSVpvn_share(HEK_KEY(hek),
1840 (HEK_UTF8(hek) ? -HEK_LEN(hek) : HEK_LEN(hek)),
1843 return sv_2mortal(sv);
1845 return sv_mortalcopy(HeKEY_sv(entry));
1849 =for apidoc hv_iterval
1851 Returns the value from the current position of the hash iterator. See
1858 Perl_hv_iterval(pTHX_ HV *hv, register HE *entry)
1860 if (SvRMAGICAL(hv)) {
1861 if (mg_find((SV*)hv, PERL_MAGIC_tied)) {
1862 SV* sv = sv_newmortal();
1863 if (HeKLEN(entry) == HEf_SVKEY)
1864 mg_copy((SV*)hv, sv, (char*)HeKEY_sv(entry), HEf_SVKEY);
1865 else mg_copy((SV*)hv, sv, HeKEY(entry), HeKLEN(entry));
1869 return HeVAL(entry);
1873 =for apidoc hv_iternextsv
1875 Performs an C<hv_iternext>, C<hv_iterkey>, and C<hv_iterval> in one
1882 Perl_hv_iternextsv(pTHX_ HV *hv, char **key, I32 *retlen)
1885 if ( (he = hv_iternext_flags(hv, 0)) == NULL)
1887 *key = hv_iterkey(he, retlen);
1888 return hv_iterval(hv, he);
1892 =for apidoc hv_magic
1894 Adds magic to a hash. See C<sv_magic>.
1900 Perl_hv_magic(pTHX_ HV *hv, GV *gv, int how)
1902 sv_magic((SV*)hv, (SV*)gv, how, Nullch, 0);
1905 #if 0 /* use the macro from hv.h instead */
1908 Perl_sharepvn(pTHX_ const char *sv, I32 len, U32 hash)
1910 return HEK_KEY(share_hek(sv, len, hash));
1915 /* possibly free a shared string if no one has access to it
1916 * len and hash must both be valid for str.
1919 Perl_unsharepvn(pTHX_ const char *str, I32 len, U32 hash)
1921 unshare_hek_or_pvn (NULL, str, len, hash);
1926 Perl_unshare_hek(pTHX_ HEK *hek)
1928 unshare_hek_or_pvn(hek, NULL, 0, 0);
1931 /* possibly free a shared string if no one has access to it
1932 hek if non-NULL takes priority over the other 3, else str, len and hash
1933 are used. If so, len and hash must both be valid for str.
1936 S_unshare_hek_or_pvn(pTHX_ HEK *hek, const char *str, I32 len, U32 hash)
1938 register XPVHV* xhv;
1940 register HE **oentry;
1943 bool is_utf8 = FALSE;
1945 const char *save = str;
1948 hash = HEK_HASH(hek);
1949 } else if (len < 0) {
1950 STRLEN tmplen = -len;
1952 /* See the note in hv_fetch(). --jhi */
1953 str = (char*)bytes_from_utf8((U8*)str, &tmplen, &is_utf8);
1956 k_flags = HVhek_UTF8;
1958 k_flags |= HVhek_WASUTF8 | HVhek_FREEKEY;
1961 /* what follows is the moral equivalent of:
1962 if ((Svp = hv_fetch(PL_strtab, tmpsv, FALSE, hash))) {
1963 if (--*Svp == Nullsv)
1964 hv_delete(PL_strtab, str, len, G_DISCARD, hash);
1966 xhv = (XPVHV*)SvANY(PL_strtab);
1967 /* assert(xhv_array != 0) */
1969 /* oentry = &(HvARRAY(hv))[hash & (I32) HvMAX(hv)]; */
1970 oentry = &((HE**)xhv->xhv_array)[hash & (I32) xhv->xhv_max];
1972 for (entry = *oentry; entry; i=0, oentry = &HeNEXT(entry), entry = *oentry) {
1973 if (HeKEY_hek(entry) != hek)
1979 int flags_masked = k_flags & HVhek_MASK;
1980 for (entry = *oentry; entry; i=0, oentry = &HeNEXT(entry), entry = *oentry) {
1981 if (HeHASH(entry) != hash) /* strings can't be equal */
1983 if (HeKLEN(entry) != len)
1985 if (HeKEY(entry) != str && memNE(HeKEY(entry),str,len)) /* is this it? */
1987 if (HeKFLAGS(entry) != flags_masked)
1995 if (--HeVAL(entry) == Nullsv) {
1996 *oentry = HeNEXT(entry);
1998 xhv->xhv_fill--; /* HvFILL(hv)-- */
1999 Safefree(HeKEY_hek(entry));
2001 xhv->xhv_keys--; /* HvKEYS(hv)-- */
2005 UNLOCK_STRTAB_MUTEX;
2006 if (!found && ckWARN_d(WARN_INTERNAL))
2007 Perl_warner(aTHX_ packWARN(WARN_INTERNAL),
2008 "Attempt to free non-existent shared string '%s'%s",
2009 hek ? HEK_KEY(hek) : str,
2010 (k_flags & HVhek_UTF8) ? " (utf8)" : "");
2011 if (k_flags & HVhek_FREEKEY)
2015 /* get a (constant) string ptr from the global string table
2016 * string will get added if it is not already there.
2017 * len and hash must both be valid for str.
2020 Perl_share_hek(pTHX_ const char *str, I32 len, register U32 hash)
2022 bool is_utf8 = FALSE;
2024 const char *save = str;
2027 STRLEN tmplen = -len;
2029 /* See the note in hv_fetch(). --jhi */
2030 str = (char*)bytes_from_utf8((U8*)str, &tmplen, &is_utf8);
2032 /* If we were able to downgrade here, then than means that we were passed
2033 in a key which only had chars 0-255, but was utf8 encoded. */
2036 /* If we found we were able to downgrade the string to bytes, then
2037 we should flag that it needs upgrading on keys or each. Also flag
2038 that we need share_hek_flags to free the string. */
2040 flags |= HVhek_WASUTF8 | HVhek_FREEKEY;
2043 return share_hek_flags (str, len, hash, flags);
2047 S_share_hek_flags(pTHX_ const char *str, I32 len, register U32 hash, int flags)
2049 register XPVHV* xhv;
2051 register HE **oentry;
2054 int flags_masked = flags & HVhek_MASK;
2056 /* what follows is the moral equivalent of:
2058 if (!(Svp = hv_fetch(PL_strtab, str, len, FALSE)))
2059 hv_store(PL_strtab, str, len, Nullsv, hash);
2061 Can't rehash the shared string table, so not sure if it's worth
2062 counting the number of entries in the linked list
2064 xhv = (XPVHV*)SvANY(PL_strtab);
2065 /* assert(xhv_array != 0) */
2067 /* oentry = &(HvARRAY(hv))[hash & (I32) HvMAX(hv)]; */
2068 oentry = &((HE**)xhv->xhv_array)[hash & (I32) xhv->xhv_max];
2069 for (entry = *oentry; entry; i=0, entry = HeNEXT(entry)) {
2070 if (HeHASH(entry) != hash) /* strings can't be equal */
2072 if (HeKLEN(entry) != len)
2074 if (HeKEY(entry) != str && memNE(HeKEY(entry),str,len)) /* is this it? */
2076 if (HeKFLAGS(entry) != flags_masked)
2083 HeKEY_hek(entry) = save_hek_flags(str, len, hash, flags);
2084 HeVAL(entry) = Nullsv;
2085 HeNEXT(entry) = *oentry;
2087 xhv->xhv_keys++; /* HvKEYS(hv)++ */
2088 if (i) { /* initial entry? */
2089 xhv->xhv_fill++; /* HvFILL(hv)++ */
2090 } else if (xhv->xhv_keys > (IV)xhv->xhv_max /* HvKEYS(hv) > HvMAX(hv) */) {
2095 ++HeVAL(entry); /* use value slot as REFCNT */
2096 UNLOCK_STRTAB_MUTEX;
2098 if (flags & HVhek_FREEKEY)
2101 return HeKEY_hek(entry);
2106 =for apidoc hv_assert
2108 Check that a hash is in an internally consistent state.
2114 Perl_hv_assert(pTHX_ HV *hv)
2118 int placeholders = 0;
2121 I32 riter = HvRITER(hv);
2122 HE *eiter = HvEITER(hv);
2124 (void)hv_iterinit(hv);
2126 while ((entry = hv_iternext_flags(hv, HV_ITERNEXT_WANTPLACEHOLDERS))) {
2127 /* sanity check the values */
2128 if (HeVAL(entry) == &PL_sv_placeholder) {
2133 /* sanity check the keys */
2134 if (HeSVKEY(entry)) {
2135 /* Don't know what to check on SV keys. */
2136 } else if (HeKUTF8(entry)) {
2138 if (HeKWASUTF8(entry)) {
2139 PerlIO_printf(Perl_debug_log,
2140 "hash key has both WASUFT8 and UTF8: '%.*s'\n",
2141 (int) HeKLEN(entry), HeKEY(entry));
2144 } else if (HeKWASUTF8(entry)) {
2148 if (!SvTIED_mg((SV*)hv, PERL_MAGIC_tied)) {
2149 if (HvUSEDKEYS(hv) != real) {
2150 PerlIO_printf(Perl_debug_log, "Count %d key(s), but hash reports %d\n",
2151 (int) real, (int) HvUSEDKEYS(hv));
2154 if (HvPLACEHOLDERS(hv) != placeholders) {
2155 PerlIO_printf(Perl_debug_log,
2156 "Count %d placeholder(s), but hash reports %d\n",
2157 (int) placeholders, (int) HvPLACEHOLDERS(hv));
2161 if (withflags && ! HvHASKFLAGS(hv)) {
2162 PerlIO_printf(Perl_debug_log,
2163 "Hash has HASKFLAGS off but I count %d key(s) with flags\n",
2170 HvRITER(hv) = riter; /* Restore hash iterator state */
2171 HvEITER(hv) = eiter;