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
174 Returns the SV which corresponds to the specified key in the hash. The
175 C<klen> is the length of the key. If C<lval> is set then the fetch will be
176 part of a store. Check that the return value is non-null before
177 dereferencing it to an C<SV*>.
179 See L<perlguts/"Understanding the Magic of Tied Hashes and Arrays"> for more
180 information on how to use this function on tied hashes.
187 Perl_hv_fetch(pTHX_ HV *hv, const char *key, I32 klen, I32 lval)
189 bool is_utf8 = FALSE;
190 const char *keysave = key;
199 STRLEN tmplen = klen;
200 /* Just casting the &klen to (STRLEN) won't work well
201 * if STRLEN and I32 are of different widths. --jhi */
202 key = (char*)bytes_from_utf8((U8*)key, &tmplen, &is_utf8);
204 /* If we were able to downgrade here, then than means that we were
205 passed in a key which only had chars 0-255, but was utf8 encoded. */
208 /* If we found we were able to downgrade the string to bytes, then
209 we should flag that it needs upgrading on keys or each. */
211 flags |= HVhek_WASUTF8 | HVhek_FREEKEY;
214 return hv_fetch_flags (hv, key, klen, lval, flags);
218 S_hv_fetch_flags(pTHX_ HV *hv, const char *key, I32 klen, I32 lval, int flags)
228 if (SvRMAGICAL(hv)) {
229 if (mg_find((SV*)hv, PERL_MAGIC_tied) || SvGMAGICAL((SV*)hv)) {
231 sv_upgrade(sv, SVt_PVLV);
232 if (flags & HVhek_UTF8) {
233 /* This hack based on the code in hv_exists_ent seems to be
234 the easiest way to pass the utf8 flag through and fix
235 the bug in hv_exists for tied hashes with utf8 keys. */
236 SV *keysv = sv_2mortal(newSVpvn(key, klen));
238 mg_copy((SV*)hv, sv, (char *)keysv, HEf_SVKEY);
240 mg_copy((SV*)hv, sv, key, klen);
242 if (flags & HVhek_FREEKEY)
245 LvTARG(sv) = sv; /* fake (SV**) */
246 return &(LvTARG(sv));
248 #ifdef ENV_IS_CASELESS
249 else if (mg_find((SV*)hv, PERL_MAGIC_env)) {
251 for (i = 0; i < klen; ++i)
252 if (isLOWER(key[i])) {
253 char *nkey = strupr(SvPVX(sv_2mortal(newSVpvn(key,klen))));
254 SV **ret = hv_fetch(hv, nkey, klen, 0);
256 ret = hv_store_flags(hv, key, klen, NEWSV(61,0), 0,
258 } else if (flags & HVhek_FREEKEY)
266 /* We use xhv->xhv_foo fields directly instead of HvFOO(hv) to
267 avoid unnecessary pointer dereferencing. */
268 xhv = (XPVHV*)SvANY(hv);
269 if (!xhv->xhv_array /* !HvARRAY(hv) */) {
271 #ifdef DYNAMIC_ENV_FETCH /* if it's an %ENV lookup, we may get it on the fly */
272 || (SvRMAGICAL((SV*)hv) && mg_find((SV*)hv, PERL_MAGIC_env))
275 Newz(503, xhv->xhv_array /* HvARRAY(hv) */,
276 PERL_HV_ARRAY_ALLOC_BYTES(xhv->xhv_max+1 /* HvMAX(hv)+1 */),
279 if (flags & HVhek_FREEKEY)
286 PERL_HASH_INTERNAL(hash, key, klen);
287 /* Yes, you do need this even though you are not "storing" because
288 you can flip the flags below if doing an lval lookup. (And that
289 was put in to give the semantics Andreas was expecting.) */
290 flags |= HVhek_REHASH;
292 PERL_HASH(hash, key, klen);
295 /* entry = (HvARRAY(hv))[hash & (I32) HvMAX(hv)]; */
296 entry = ((HE**)xhv->xhv_array)[hash & (I32) xhv->xhv_max];
297 for (; entry; entry = HeNEXT(entry)) {
298 if (!HeKEY_hek(entry))
300 if (HeHASH(entry) != hash) /* strings can't be equal */
302 if (HeKLEN(entry) != (I32)klen)
304 if (HeKEY(entry) != key && memNE(HeKEY(entry),key,klen)) /* is this it? */
306 /* flags is 0 if not utf8. need HeKFLAGS(entry) also 0.
307 flags is 1 if utf8. need HeKFLAGS(entry) also 1.
308 xor is true if bits differ, in which case this isn't a match. */
309 if ((HeKFLAGS(entry) ^ flags) & HVhek_UTF8)
311 if (lval && HeKFLAGS(entry) != flags) {
312 /* We match if HVhek_UTF8 bit in our flags and hash key's match.
313 But if entry was set previously with HVhek_WASUTF8 and key now
314 doesn't (or vice versa) then we should change the key's flag,
315 as this is assignment. */
316 if (HvSHAREKEYS(hv)) {
317 /* Need to swap the key we have for a key with the flags we
318 need. As keys are shared we can't just write to the flag,
319 so we share the new one, unshare the old one. */
320 int flags_nofree = flags & ~HVhek_FREEKEY;
321 HEK *new_hek = share_hek_flags(key, klen, hash, flags_nofree);
322 unshare_hek (HeKEY_hek(entry));
323 HeKEY_hek(entry) = new_hek;
326 HeKFLAGS(entry) = flags;
327 if (flags & HVhek_ENABLEHVKFLAGS)
330 if (flags & HVhek_FREEKEY)
332 /* if we find a placeholder, we pretend we haven't found anything */
333 if (HeVAL(entry) == &PL_sv_placeholder)
335 return &HeVAL(entry);
338 #ifdef DYNAMIC_ENV_FETCH /* %ENV lookup? If so, try to fetch the value now */
339 if (SvRMAGICAL((SV*)hv) && mg_find((SV*)hv, PERL_MAGIC_env)) {
341 char *env = PerlEnv_ENVgetenv_len(key,&len);
343 sv = newSVpvn(env,len);
345 if (flags & HVhek_FREEKEY)
347 return hv_store(hv,key,klen,sv,hash);
351 if (!entry && SvREADONLY(hv)) {
352 S_hv_notallowed(aTHX_ flags, key, klen,
353 "access disallowed key '%"SVf"' in"
356 if (lval) { /* gonna assign to this, so it better be there */
358 return hv_store_flags(hv,key,klen,sv,hash,flags);
360 if (flags & HVhek_FREEKEY)
365 /* returns an HE * structure with the all fields set */
366 /* note that hent_val will be a mortal sv for MAGICAL hashes */
368 =for apidoc hv_fetch_ent
370 Returns the hash entry which corresponds to the specified key in the hash.
371 C<hash> must be a valid precomputed hash number for the given C<key>, or 0
372 if you want the function to compute it. IF C<lval> is set then the fetch
373 will be part of a store. Make sure the return value is non-null before
374 accessing it. The return value when C<tb> is a tied hash is a pointer to a
375 static location, so be sure to make a copy of the structure if you need to
378 See L<perlguts/"Understanding the Magic of Tied Hashes and Arrays"> for more
379 information on how to use this function on tied hashes.
385 Perl_hv_fetch_ent(pTHX_ HV *hv, SV *keysv, I32 lval, register U32 hash)
399 if (SvRMAGICAL(hv)) {
400 if (mg_find((SV*)hv, PERL_MAGIC_tied) || SvGMAGICAL((SV*)hv)) {
402 keysv = newSVsv(keysv);
403 mg_copy((SV*)hv, sv, (char*)keysv, HEf_SVKEY);
404 /* grab a fake HE/HEK pair from the pool or make a new one */
405 entry = PL_hv_fetch_ent_mh;
407 PL_hv_fetch_ent_mh = HeNEXT(entry);
411 New(54, k, HEK_BASESIZE + sizeof(SV*), char);
412 HeKEY_hek(entry) = (HEK*)k;
414 HeNEXT(entry) = Nullhe;
415 HeSVKEY_set(entry, keysv);
417 sv_upgrade(sv, SVt_PVLV);
419 LvTARG(sv) = (SV*)entry; /* so we can free entry when freeing sv */
422 #ifdef ENV_IS_CASELESS
423 else if (mg_find((SV*)hv, PERL_MAGIC_env)) {
425 key = SvPV(keysv, klen);
426 for (i = 0; i < klen; ++i)
427 if (isLOWER(key[i])) {
428 SV *nkeysv = sv_2mortal(newSVpvn(key,klen));
429 (void)strupr(SvPVX(nkeysv));
430 entry = hv_fetch_ent(hv, nkeysv, 0, 0);
432 entry = hv_store_ent(hv, keysv, NEWSV(61,0), hash);
439 keysave = key = SvPV(keysv, klen);
440 xhv = (XPVHV*)SvANY(hv);
441 if (!xhv->xhv_array /* !HvARRAY(hv) */) {
443 #ifdef DYNAMIC_ENV_FETCH /* if it's an %ENV lookup, we may get it on the fly */
444 || (SvRMAGICAL((SV*)hv) && mg_find((SV*)hv, PERL_MAGIC_env))
447 Newz(503, xhv->xhv_array /* HvARRAY(hv) */,
448 PERL_HV_ARRAY_ALLOC_BYTES(xhv->xhv_max+1 /* HvMAX(hv)+1 */),
454 is_utf8 = (SvUTF8(keysv)!=0);
457 key = (char*)bytes_from_utf8((U8*)key, &klen, &is_utf8);
461 flags |= HVhek_WASUTF8 | HVhek_FREEKEY;
465 PERL_HASH_INTERNAL(hash, key, klen);
466 /* Yes, you do need this even though you are not "storing" because
467 you can flip the flags below if doing an lval lookup. (And that
468 was put in to give the semantics Andreas was expecting.) */
469 flags |= HVhek_REHASH;
471 if SvIsCOW_shared_hash(keysv) {
474 PERL_HASH(hash, key, klen);
478 /* entry = (HvARRAY(hv))[hash & (I32) HvMAX(hv)]; */
479 entry = ((HE**)xhv->xhv_array)[hash & (I32) xhv->xhv_max];
480 for (; entry; entry = HeNEXT(entry)) {
481 if (HeHASH(entry) != hash) /* strings can't be equal */
483 if (HeKLEN(entry) != (I32)klen)
485 if (HeKEY(entry) != key && memNE(HeKEY(entry),key,klen)) /* is this it? */
487 if ((HeKFLAGS(entry) ^ flags) & HVhek_UTF8)
489 if (lval && HeKFLAGS(entry) != flags) {
490 /* We match if HVhek_UTF8 bit in our flags and hash key's match.
491 But if entry was set previously with HVhek_WASUTF8 and key now
492 doesn't (or vice versa) then we should change the key's flag,
493 as this is assignment. */
494 if (HvSHAREKEYS(hv)) {
495 /* Need to swap the key we have for a key with the flags we
496 need. As keys are shared we can't just write to the flag,
497 so we share the new one, unshare the old one. */
498 int flags_nofree = flags & ~HVhek_FREEKEY;
499 HEK *new_hek = share_hek_flags(key, klen, hash, flags_nofree);
500 unshare_hek (HeKEY_hek(entry));
501 HeKEY_hek(entry) = new_hek;
504 HeKFLAGS(entry) = flags;
505 if (flags & HVhek_ENABLEHVKFLAGS)
510 /* if we find a placeholder, we pretend we haven't found anything */
511 if (HeVAL(entry) == &PL_sv_placeholder)
515 #ifdef DYNAMIC_ENV_FETCH /* %ENV lookup? If so, try to fetch the value now */
516 if (SvRMAGICAL((SV*)hv) && mg_find((SV*)hv, PERL_MAGIC_env)) {
518 char *env = PerlEnv_ENVgetenv_len(key,&len);
520 sv = newSVpvn(env,len);
522 return hv_store_ent(hv,keysv,sv,hash);
526 if (!entry && SvREADONLY(hv)) {
527 S_hv_notallowed(aTHX_ flags, key, klen,
528 "access disallowed key '%"SVf"' in"
531 if (flags & HVhek_FREEKEY)
533 if (lval) { /* gonna assign to this, so it better be there */
535 return hv_store_ent(hv,keysv,sv,hash);
541 S_hv_magic_check(pTHX_ HV *hv, bool *needs_copy, bool *needs_store)
543 MAGIC *mg = SvMAGIC(hv);
547 if (isUPPER(mg->mg_type)) {
549 switch (mg->mg_type) {
550 case PERL_MAGIC_tied:
552 *needs_store = FALSE;
555 mg = mg->mg_moremagic;
562 Stores an SV in a hash. The hash key is specified as C<key> and C<klen> is
563 the length of the key. The C<hash> parameter is the precomputed hash
564 value; if it is zero then Perl will compute it. The return value will be
565 NULL if the operation failed or if the value did not need to be actually
566 stored within the hash (as in the case of tied hashes). Otherwise it can
567 be dereferenced to get the original C<SV*>. Note that the caller is
568 responsible for suitably incrementing the reference count of C<val> before
569 the call, and decrementing it if the function returned NULL. Effectively
570 a successful hv_store takes ownership of one reference to C<val>. This is
571 usually what you want; a newly created SV has a reference count of one, so
572 if all your code does is create SVs then store them in a hash, hv_store
573 will own the only reference to the new SV, and your code doesn't need to do
574 anything further to tidy up. hv_store is not implemented as a call to
575 hv_store_ent, and does not create a temporary SV for the key, so if your
576 key data is not already in SV form then use hv_store in preference to
579 See L<perlguts/"Understanding the Magic of Tied Hashes and Arrays"> for more
580 information on how to use this function on tied hashes.
586 Perl_hv_store(pTHX_ HV *hv, const char *key, I32 klen, SV *val, U32 hash)
588 bool is_utf8 = FALSE;
589 const char *keysave = key;
598 STRLEN tmplen = klen;
599 /* Just casting the &klen to (STRLEN) won't work well
600 * if STRLEN and I32 are of different widths. --jhi */
601 key = (char*)bytes_from_utf8((U8*)key, &tmplen, &is_utf8);
603 /* If we were able to downgrade here, then than means that we were
604 passed in a key which only had chars 0-255, but was utf8 encoded. */
607 /* If we found we were able to downgrade the string to bytes, then
608 we should flag that it needs upgrading on keys or each. */
610 flags |= HVhek_WASUTF8 | HVhek_FREEKEY;
613 return hv_store_flags (hv, key, klen, val, hash, flags);
617 Perl_hv_store_flags(pTHX_ HV *hv, const char *key, I32 klen, SV *val,
618 register U32 hash, int flags)
621 register U32 n_links;
623 register HE **oentry;
628 xhv = (XPVHV*)SvANY(hv);
632 hv_magic_check (hv, &needs_copy, &needs_store);
634 if (flags & HVhek_UTF8) {
635 /* This hack based on the code in hv_exists_ent seems to be
636 the easiest way to pass the utf8 flag through and fix
637 the bug in hv_exists for tied hashes with utf8 keys. */
638 SV *keysv = sv_2mortal(newSVpvn(key, klen));
640 mg_copy((SV*)hv, val, (char *)keysv, HEf_SVKEY);
642 mg_copy((SV*)hv, val, key, klen);
644 if (!xhv->xhv_array /* !HvARRAY */ && !needs_store) {
645 if (flags & HVhek_FREEKEY)
649 #ifdef ENV_IS_CASELESS
650 else if (mg_find((SV*)hv, PERL_MAGIC_env)) {
651 key = savepvn(key,klen);
652 key = (const char*)strupr((char*)key);
660 HvHASKFLAGS_on((SV*)hv);
663 /* We don't have a pointer to the hv, so we have to replicate the
664 flag into every HEK, so that hv_iterkeysv can see it. */
665 flags |= HVhek_REHASH;
666 PERL_HASH_INTERNAL(hash, key, klen);
668 PERL_HASH(hash, key, klen);
670 if (!xhv->xhv_array /* !HvARRAY(hv) */)
671 Newz(505, xhv->xhv_array /* HvARRAY(hv) */,
672 PERL_HV_ARRAY_ALLOC_BYTES(xhv->xhv_max+1 /* HvMAX(hv)+1 */),
675 /* oentry = &(HvARRAY(hv))[hash & (I32) HvMAX(hv)]; */
676 oentry = &((HE**)xhv->xhv_array)[hash & (I32) xhv->xhv_max];
680 for (entry = *oentry; entry; ++n_links, entry = HeNEXT(entry)) {
681 if (HeHASH(entry) != hash) /* strings can't be equal */
683 if (HeKLEN(entry) != (I32)klen)
685 if (HeKEY(entry) != key && memNE(HeKEY(entry),key,klen)) /* is this it? */
687 if ((HeKFLAGS(entry) ^ flags) & HVhek_UTF8)
689 if (HeVAL(entry) == &PL_sv_placeholder)
690 xhv->xhv_placeholders--; /* yes, can store into placeholder slot */
692 SvREFCNT_dec(HeVAL(entry));
693 if (flags & HVhek_PLACEHOLD) {
694 /* We have been requested to insert a placeholder. Currently
695 only Storable is allowed to do this. */
696 xhv->xhv_placeholders++;
697 HeVAL(entry) = &PL_sv_placeholder;
701 if (HeKFLAGS(entry) != flags) {
702 /* We match if HVhek_UTF8 bit in our flags and hash key's match.
703 But if entry was set previously with HVhek_WASUTF8 and key now
704 doesn't (or vice versa) then we should change the key's flag,
705 as this is assignment. */
706 if (HvSHAREKEYS(hv)) {
707 /* Need to swap the key we have for a key with the flags we
708 need. As keys are shared we can't just write to the flag,
709 so we share the new one, unshare the old one. */
710 int flags_nofree = flags & ~HVhek_FREEKEY;
711 HEK *new_hek = share_hek_flags(key, klen, hash, flags_nofree);
712 unshare_hek (HeKEY_hek(entry));
713 HeKEY_hek(entry) = new_hek;
716 HeKFLAGS(entry) = flags;
718 if (flags & HVhek_FREEKEY)
720 return &HeVAL(entry);
723 if (SvREADONLY(hv)) {
724 S_hv_notallowed(aTHX_ flags, key, klen,
725 "access disallowed key '%"SVf"' to"
730 /* share_hek_flags will do the free for us. This might be considered
733 HeKEY_hek(entry) = share_hek_flags(key, klen, hash, flags);
734 else /* gotta do the real thing */
735 HeKEY_hek(entry) = save_hek_flags(key, klen, hash, flags);
736 if (flags & HVhek_PLACEHOLD) {
737 /* We have been requested to insert a placeholder. Currently
738 only Storable is allowed to do this. */
739 xhv->xhv_placeholders++;
740 HeVAL(entry) = &PL_sv_placeholder;
743 HeNEXT(entry) = *oentry;
746 xhv->xhv_keys++; /* HvKEYS(hv)++ */
747 if (!n_links) { /* initial entry? */
748 xhv->xhv_fill++; /* HvFILL(hv)++ */
749 } else if ((xhv->xhv_keys > (IV)xhv->xhv_max)
750 || ((n_links > HV_MAX_LENGTH_BEFORE_SPLIT) && !HvREHASH(hv))) {
751 /* Use the old HvKEYS(hv) > HvMAX(hv) condition to limit bucket
752 splits on a rehashed hash, as we're not going to split it again,
753 and if someone is lucky (evil) enough to get all the keys in one
754 list they could exhaust our memory as we repeatedly double the
755 number of buckets on every entry. Linear search feels a less worse
760 return &HeVAL(entry);
764 =for apidoc hv_store_ent
766 Stores C<val> in a hash. The hash key is specified as C<key>. The C<hash>
767 parameter is the precomputed hash value; if it is zero then Perl will
768 compute it. The return value is the new hash entry so created. It will be
769 NULL if the operation failed or if the value did not need to be actually
770 stored within the hash (as in the case of tied hashes). Otherwise the
771 contents of the return value can be accessed using the C<He?> macros
772 described here. Note that the caller is responsible for suitably
773 incrementing the reference count of C<val> before the call, and
774 decrementing it if the function returned NULL. Effectively a successful
775 hv_store_ent takes ownership of one reference to C<val>. This is
776 usually what you want; a newly created SV has a reference count of one, so
777 if all your code does is create SVs then store them in a hash, hv_store
778 will own the only reference to the new SV, and your code doesn't need to do
779 anything further to tidy up. Note that hv_store_ent only reads the C<key>;
780 unlike C<val> it does not take ownership of it, so maintaining the correct
781 reference count on C<key> is entirely the caller's responsibility. hv_store
782 is not implemented as a call to hv_store_ent, and does not create a temporary
783 SV for the key, so if your key data is not already in SV form then use
784 hv_store in preference to hv_store_ent.
786 See L<perlguts/"Understanding the Magic of Tied Hashes and Arrays"> for more
787 information on how to use this function on tied hashes.
793 Perl_hv_store_ent(pTHX_ HV *hv, SV *keysv, SV *val, U32 hash)
808 xhv = (XPVHV*)SvANY(hv);
812 hv_magic_check (hv, &needs_copy, &needs_store);
814 bool save_taint = PL_tainted;
816 PL_tainted = SvTAINTED(keysv);
817 keysv = sv_2mortal(newSVsv(keysv));
818 mg_copy((SV*)hv, val, (char*)keysv, HEf_SVKEY);
819 TAINT_IF(save_taint);
820 if (!xhv->xhv_array /* !HvARRAY(hv) */ && !needs_store)
822 #ifdef ENV_IS_CASELESS
823 else if (mg_find((SV*)hv, PERL_MAGIC_env)) {
824 key = SvPV(keysv, klen);
825 keysv = sv_2mortal(newSVpvn(key,klen));
826 (void)strupr(SvPVX(keysv));
833 keysave = key = SvPV(keysv, klen);
834 is_utf8 = (SvUTF8(keysv) != 0);
837 key = (char*)bytes_from_utf8((U8*)key, &klen, &is_utf8);
841 flags |= HVhek_WASUTF8 | HVhek_FREEKEY;
842 HvHASKFLAGS_on((SV*)hv);
846 /* We don't have a pointer to the hv, so we have to replicate the
847 flag into every HEK, so that hv_iterkeysv can see it. */
848 flags |= HVhek_REHASH;
849 PERL_HASH_INTERNAL(hash, key, klen);
851 if SvIsCOW_shared_hash(keysv) {
854 PERL_HASH(hash, key, klen);
858 if (!xhv->xhv_array /* !HvARRAY(hv) */)
859 Newz(505, xhv->xhv_array /* HvARRAY(hv) */,
860 PERL_HV_ARRAY_ALLOC_BYTES(xhv->xhv_max+1 /* HvMAX(hv)+1 */),
863 /* oentry = &(HvARRAY(hv))[hash & (I32) HvMAX(hv)]; */
864 oentry = &((HE**)xhv->xhv_array)[hash & (I32) xhv->xhv_max];
867 for (; entry; ++n_links, entry = HeNEXT(entry)) {
868 if (HeHASH(entry) != hash) /* strings can't be equal */
870 if (HeKLEN(entry) != (I32)klen)
872 if (HeKEY(entry) != key && memNE(HeKEY(entry),key,klen)) /* is this it? */
874 if ((HeKFLAGS(entry) ^ flags) & HVhek_UTF8)
876 if (HeVAL(entry) == &PL_sv_placeholder)
877 xhv->xhv_placeholders--; /* yes, can store into placeholder slot */
879 SvREFCNT_dec(HeVAL(entry));
881 if (HeKFLAGS(entry) != flags) {
882 /* We match if HVhek_UTF8 bit in our flags and hash key's match.
883 But if entry was set previously with HVhek_WASUTF8 and key now
884 doesn't (or vice versa) then we should change the key's flag,
885 as this is assignment. */
886 if (HvSHAREKEYS(hv)) {
887 /* Need to swap the key we have for a key with the flags we
888 need. As keys are shared we can't just write to the flag,
889 so we share the new one, unshare the old one. */
890 int flags_nofree = flags & ~HVhek_FREEKEY;
891 HEK *new_hek = share_hek_flags(key, klen, hash, flags_nofree);
892 unshare_hek (HeKEY_hek(entry));
893 HeKEY_hek(entry) = new_hek;
896 HeKFLAGS(entry) = flags;
898 if (flags & HVhek_FREEKEY)
903 if (SvREADONLY(hv)) {
904 S_hv_notallowed(aTHX_ flags, key, klen,
905 "access disallowed key '%"SVf"' to"
910 /* share_hek_flags will do the free for us. This might be considered
913 HeKEY_hek(entry) = share_hek_flags(key, klen, hash, flags);
914 else /* gotta do the real thing */
915 HeKEY_hek(entry) = save_hek_flags(key, klen, hash, flags);
917 HeNEXT(entry) = *oentry;
920 xhv->xhv_keys++; /* HvKEYS(hv)++ */
921 if (!n_links) { /* initial entry? */
922 xhv->xhv_fill++; /* HvFILL(hv)++ */
923 } else if ((xhv->xhv_keys > (IV)xhv->xhv_max)
924 || ((n_links > HV_MAX_LENGTH_BEFORE_SPLIT) && !HvREHASH(hv))) {
925 /* Use only the old HvKEYS(hv) > HvMAX(hv) condition to limit bucket
926 splits on a rehashed hash, as we're not going to split it again,
927 and if someone is lucky (evil) enough to get all the keys in one
928 list they could exhaust our memory as we repeatedly double the
929 number of buckets on every entry. Linear search feels a less worse
938 =for apidoc hv_delete
940 Deletes a key/value pair in the hash. The value SV is removed from the
941 hash and returned to the caller. The C<klen> is the length of the key.
942 The C<flags> value will normally be zero; if set to G_DISCARD then NULL
949 Perl_hv_delete(pTHX_ HV *hv, const char *key, I32 klen, I32 flags)
951 return hv_delete_common(hv, NULL, key, klen, flags, 0);
955 =for apidoc hv_delete_ent
957 Deletes a key/value pair in the hash. The value SV is removed from the
958 hash and returned to the caller. The C<flags> value will normally be zero;
959 if set to G_DISCARD then NULL will be returned. C<hash> can be a valid
960 precomputed hash value, or 0 to ask for it to be computed.
966 Perl_hv_delete_ent(pTHX_ HV *hv, SV *keysv, I32 flags, U32 hash)
968 return hv_delete_common(hv, keysv, NULL, 0, flags, hash);
972 S_hv_delete_common(pTHX_ HV *hv, SV *keysv, const char *key, I32 klen_i32,
979 register HE **oentry;
989 key = SvPV(keysv, klen);
990 is_utf8 = (SvUTF8(keysv) != 0);
1002 if (SvRMAGICAL(hv)) {
1005 hv_magic_check (hv, &needs_copy, &needs_store);
1010 if ((entry = hv_fetch_ent(hv, keysv, TRUE, hash))) {
1015 if ((svp = hv_fetch(hv, key, is_utf8 ? -klen : klen, TRUE))) {
1020 if (SvMAGICAL(sv)) {
1024 if (mg_find(sv, PERL_MAGIC_tiedelem)) {
1025 /* No longer an element */
1026 sv_unmagic(sv, PERL_MAGIC_tiedelem);
1029 return Nullsv; /* element cannot be deleted */
1032 #ifdef ENV_IS_CASELESS
1033 else if (mg_find((SV*)hv, PERL_MAGIC_env)) {
1034 /* XXX This code isn't UTF8 clean. */
1035 keysv = sv_2mortal(newSVpvn(key,klen));
1036 keysave = key = strupr(SvPVX(keysv));
1043 xhv = (XPVHV*)SvANY(hv);
1044 if (!xhv->xhv_array /* !HvARRAY(hv) */)
1048 key = (char*)bytes_from_utf8((U8*)key, &klen, &is_utf8);
1050 k_flags = HVhek_UTF8;
1052 k_flags |= HVhek_FREEKEY;
1056 PERL_HASH_INTERNAL(hash, key, klen);
1058 PERL_HASH(hash, key, klen);
1061 /* oentry = &(HvARRAY(hv))[hash & (I32) HvMAX(hv)]; */
1062 oentry = &((HE**)xhv->xhv_array)[hash & (I32) xhv->xhv_max];
1065 for (; entry; i=0, oentry = &HeNEXT(entry), entry = *oentry) {
1066 if (HeHASH(entry) != hash) /* strings can't be equal */
1068 if (HeKLEN(entry) != (I32)klen)
1070 if (HeKEY(entry) != key && memNE(HeKEY(entry),key,klen)) /* is this it? */
1072 if ((HeKFLAGS(entry) ^ k_flags) & HVhek_UTF8)
1074 if (k_flags & HVhek_FREEKEY)
1077 /* if placeholder is here, it's already been deleted.... */
1078 if (HeVAL(entry) == &PL_sv_placeholder)
1081 return Nullsv; /* if still SvREADONLY, leave it deleted. */
1083 /* okay, really delete the placeholder. */
1084 *oentry = HeNEXT(entry);
1086 xhv->xhv_fill--; /* HvFILL(hv)-- */
1087 if (entry == xhv->xhv_eiter /* HvEITER(hv) */)
1090 hv_free_ent(hv, entry);
1091 xhv->xhv_keys--; /* HvKEYS(hv)-- */
1092 if (xhv->xhv_keys == 0)
1093 HvHASKFLAGS_off(hv);
1094 xhv->xhv_placeholders--;
1097 else if (SvREADONLY(hv) && HeVAL(entry) && SvREADONLY(HeVAL(entry))) {
1098 S_hv_notallowed(aTHX_ k_flags, key, klen,
1099 "delete readonly key '%"SVf"' from"
1103 if (flags & G_DISCARD)
1106 sv = sv_2mortal(HeVAL(entry));
1107 HeVAL(entry) = &PL_sv_placeholder;
1111 * If a restricted hash, rather than really deleting the entry, put
1112 * a placeholder there. This marks the key as being "approved", so
1113 * we can still access via not-really-existing key without raising
1116 if (SvREADONLY(hv)) {
1117 HeVAL(entry) = &PL_sv_placeholder;
1118 /* We'll be saving this slot, so the number of allocated keys
1119 * doesn't go down, but the number placeholders goes up */
1120 xhv->xhv_placeholders++; /* HvPLACEHOLDERS(hv)++ */
1122 *oentry = HeNEXT(entry);
1124 xhv->xhv_fill--; /* HvFILL(hv)-- */
1125 if (entry == xhv->xhv_eiter /* HvEITER(hv) */)
1128 hv_free_ent(hv, entry);
1129 xhv->xhv_keys--; /* HvKEYS(hv)-- */
1130 if (xhv->xhv_keys == 0)
1131 HvHASKFLAGS_off(hv);
1135 if (SvREADONLY(hv)) {
1136 S_hv_notallowed(aTHX_ k_flags, key, klen,
1137 "delete disallowed key '%"SVf"' from"
1141 if (k_flags & HVhek_FREEKEY)
1147 =for apidoc hv_exists
1149 Returns a boolean indicating whether the specified hash key exists. The
1150 C<klen> is the length of the key.
1156 Perl_hv_exists(pTHX_ HV *hv, const char *key, I32 klen)
1158 return hv_exists_common(hv, NULL, key, klen, 0);
1162 =for apidoc hv_exists_ent
1164 Returns a boolean indicating whether the specified hash key exists. C<hash>
1165 can be a valid precomputed hash value, or 0 to ask for it to be
1172 Perl_hv_exists_ent(pTHX_ HV *hv, SV *keysv, U32 hash)
1174 return hv_exists_common(hv, keysv, NULL, 0, hash);
1178 S_hv_exists_common(pTHX_ HV *hv, SV *keysv, const char *key, I32 klen_i32,
1181 register XPVHV* xhv;
1186 const char *keysave;
1193 key = SvPV(keysv, klen);
1194 is_utf8 = (SvUTF8(keysv) != 0);
1206 if (SvRMAGICAL(hv)) {
1207 if (mg_find((SV*)hv, PERL_MAGIC_tied) || SvGMAGICAL((SV*)hv)) {
1210 if (keysv || is_utf8) {
1212 keysv = newSVpvn(key, klen);
1215 keysv = newSVsv(keysv);
1217 key = (char *)sv_2mortal(keysv);
1221 /* I don't understand why hv_exists_ent has svret and sv,
1222 whereas hv_exists only had one. */
1223 svret = sv_newmortal();
1224 sv = sv_newmortal();
1225 mg_copy((SV*)hv, sv, key, klen);
1226 magic_existspack(svret, mg_find(sv, PERL_MAGIC_tiedelem));
1227 return (bool)SvTRUE(svret);
1229 #ifdef ENV_IS_CASELESS
1230 else if (mg_find((SV*)hv, PERL_MAGIC_env)) {
1231 /* XXX This code isn't UTF8 clean. */
1232 keysv = sv_2mortal(newSVpvn(key,klen));
1233 keysave = key = strupr(SvPVX(keysv));
1240 xhv = (XPVHV*)SvANY(hv);
1241 #ifndef DYNAMIC_ENV_FETCH
1242 if (!xhv->xhv_array /* !HvARRAY(hv) */)
1247 key = (char*)bytes_from_utf8((U8*)key, &klen, &is_utf8);
1249 k_flags = HVhek_UTF8;
1251 k_flags |= HVhek_FREEKEY;
1254 PERL_HASH_INTERNAL(hash, key, klen);
1256 PERL_HASH(hash, key, klen);
1258 #ifdef DYNAMIC_ENV_FETCH
1259 if (!xhv->xhv_array /* !HvARRAY(hv) */) entry = Null(HE*);
1262 /* entry = (HvARRAY(hv))[hash & (I32) HvMAX(hv)]; */
1263 entry = ((HE**)xhv->xhv_array)[hash & (I32) xhv->xhv_max];
1264 for (; entry; entry = HeNEXT(entry)) {
1265 if (HeHASH(entry) != hash) /* strings can't be equal */
1267 if (HeKLEN(entry) != (I32)klen)
1269 if (HeKEY(entry) != key && memNE(HeKEY(entry),key,klen)) /* is this it? */
1271 if ((HeKFLAGS(entry) ^ k_flags) & HVhek_UTF8)
1273 if (k_flags & HVhek_FREEKEY)
1275 /* If we find the key, but the value is a placeholder, return false. */
1276 if (HeVAL(entry) == &PL_sv_placeholder)
1280 #ifdef DYNAMIC_ENV_FETCH /* is it out there? */
1281 if (SvRMAGICAL((SV*)hv) && mg_find((SV*)hv, PERL_MAGIC_env)) {
1283 char *env = PerlEnv_ENVgetenv_len(key,&len);
1285 sv = newSVpvn(env,len);
1287 (void)hv_store_ent(hv,keysv,sv,hash);
1288 if (k_flags & HVhek_FREEKEY)
1294 if (k_flags & HVhek_FREEKEY)
1301 S_hsplit(pTHX_ HV *hv)
1303 register XPVHV* xhv = (XPVHV*)SvANY(hv);
1304 I32 oldsize = (I32) xhv->xhv_max+1; /* HvMAX(hv)+1 (sick) */
1305 register I32 newsize = oldsize * 2;
1307 register char *a = xhv->xhv_array; /* HvARRAY(hv) */
1311 register HE **oentry;
1312 int longest_chain = 0;
1316 #if defined(STRANGE_MALLOC) || defined(MYMALLOC)
1317 Renew(a, PERL_HV_ARRAY_ALLOC_BYTES(newsize), char);
1323 New(2, a, PERL_HV_ARRAY_ALLOC_BYTES(newsize), char);
1328 Copy(xhv->xhv_array /* HvARRAY(hv) */, a, oldsize * sizeof(HE*), char);
1329 if (oldsize >= 64) {
1330 offer_nice_chunk(xhv->xhv_array /* HvARRAY(hv) */,
1331 PERL_HV_ARRAY_ALLOC_BYTES(oldsize));
1334 Safefree(xhv->xhv_array /* HvARRAY(hv) */);
1338 Zero(&a[oldsize * sizeof(HE*)], (newsize-oldsize) * sizeof(HE*), char); /* zero 2nd half*/
1339 xhv->xhv_max = --newsize; /* HvMAX(hv) = --newsize */
1340 xhv->xhv_array = a; /* HvARRAY(hv) = a */
1343 for (i=0; i<oldsize; i++,aep++) {
1344 int left_length = 0;
1345 int right_length = 0;
1347 if (!*aep) /* non-existent */
1350 for (oentry = aep, entry = *aep; entry; entry = *oentry) {
1351 if ((HeHASH(entry) & newsize) != (U32)i) {
1352 *oentry = HeNEXT(entry);
1353 HeNEXT(entry) = *bep;
1355 xhv->xhv_fill++; /* HvFILL(hv)++ */
1361 oentry = &HeNEXT(entry);
1365 if (!*aep) /* everything moved */
1366 xhv->xhv_fill--; /* HvFILL(hv)-- */
1367 /* I think we don't actually need to keep track of the longest length,
1368 merely flag if anything is too long. But for the moment while
1369 developing this code I'll track it. */
1370 if (left_length > longest_chain)
1371 longest_chain = left_length;
1372 if (right_length > longest_chain)
1373 longest_chain = right_length;
1377 /* Pick your policy for "hashing isn't working" here: */
1378 if (longest_chain <= HV_MAX_LENGTH_BEFORE_SPLIT /* split worked? */
1383 if (hv == PL_strtab) {
1384 /* Urg. Someone is doing something nasty to the string table.
1389 /* Awooga. Awooga. Pathological data. */
1390 /*PerlIO_printf(PerlIO_stderr(), "%p %d of %d with %d/%d buckets\n", hv,
1391 longest_chain, HvTOTALKEYS(hv), HvFILL(hv), 1+HvMAX(hv));*/
1394 Newz(2, a, PERL_HV_ARRAY_ALLOC_BYTES(newsize), char);
1395 was_shared = HvSHAREKEYS(hv);
1398 HvSHAREKEYS_off(hv);
1401 aep = (HE **) xhv->xhv_array;
1403 for (i=0; i<newsize; i++,aep++) {
1406 /* We're going to trash this HE's next pointer when we chain it
1407 into the new hash below, so store where we go next. */
1408 HE *next = HeNEXT(entry);
1412 PERL_HASH_INTERNAL(hash, HeKEY(entry), HeKLEN(entry));
1417 = save_hek_flags(HeKEY(entry), HeKLEN(entry),
1418 hash, HeKFLAGS(entry));
1419 unshare_hek (HeKEY_hek(entry));
1420 HeKEY_hek(entry) = new_hek;
1422 /* Not shared, so simply write the new hash in. */
1423 HeHASH(entry) = hash;
1425 /*PerlIO_printf(PerlIO_stderr(), "%d ", HeKFLAGS(entry));*/
1426 HEK_REHASH_on(HeKEY_hek(entry));
1427 /*PerlIO_printf(PerlIO_stderr(), "%d\n", HeKFLAGS(entry));*/
1429 /* Copy oentry to the correct new chain. */
1430 bep = ((HE**)a) + (hash & (I32) xhv->xhv_max);
1432 xhv->xhv_fill++; /* HvFILL(hv)++ */
1433 HeNEXT(entry) = *bep;
1439 Safefree (xhv->xhv_array);
1440 xhv->xhv_array = a; /* HvARRAY(hv) = a */
1444 Perl_hv_ksplit(pTHX_ HV *hv, IV newmax)
1446 register XPVHV* xhv = (XPVHV*)SvANY(hv);
1447 I32 oldsize = (I32) xhv->xhv_max+1; /* HvMAX(hv)+1 (sick) */
1448 register I32 newsize;
1454 register HE **oentry;
1456 newsize = (I32) newmax; /* possible truncation here */
1457 if (newsize != newmax || newmax <= oldsize)
1459 while ((newsize & (1 + ~newsize)) != newsize) {
1460 newsize &= ~(newsize & (1 + ~newsize)); /* get proper power of 2 */
1462 if (newsize < newmax)
1464 if (newsize < newmax)
1465 return; /* overflow detection */
1467 a = xhv->xhv_array; /* HvARRAY(hv) */
1470 #if defined(STRANGE_MALLOC) || defined(MYMALLOC)
1471 Renew(a, PERL_HV_ARRAY_ALLOC_BYTES(newsize), char);
1477 New(2, a, PERL_HV_ARRAY_ALLOC_BYTES(newsize), char);
1482 Copy(xhv->xhv_array /* HvARRAY(hv) */, a, oldsize * sizeof(HE*), char);
1483 if (oldsize >= 64) {
1484 offer_nice_chunk(xhv->xhv_array /* HvARRAY(hv) */,
1485 PERL_HV_ARRAY_ALLOC_BYTES(oldsize));
1488 Safefree(xhv->xhv_array /* HvARRAY(hv) */);
1491 Zero(&a[oldsize * sizeof(HE*)], (newsize-oldsize) * sizeof(HE*), char); /* zero 2nd half*/
1494 Newz(0, a, PERL_HV_ARRAY_ALLOC_BYTES(newsize), char);
1496 xhv->xhv_max = --newsize; /* HvMAX(hv) = --newsize */
1497 xhv->xhv_array = a; /* HvARRAY(hv) = a */
1498 if (!xhv->xhv_fill /* !HvFILL(hv) */) /* skip rest if no entries */
1502 for (i=0; i<oldsize; i++,aep++) {
1503 if (!*aep) /* non-existent */
1505 for (oentry = aep, entry = *aep; entry; entry = *oentry) {
1506 if ((j = (HeHASH(entry) & newsize)) != i) {
1508 *oentry = HeNEXT(entry);
1509 if (!(HeNEXT(entry) = aep[j]))
1510 xhv->xhv_fill++; /* HvFILL(hv)++ */
1515 oentry = &HeNEXT(entry);
1517 if (!*aep) /* everything moved */
1518 xhv->xhv_fill--; /* HvFILL(hv)-- */
1525 Creates a new HV. The reference count is set to 1.
1534 register XPVHV* xhv;
1536 hv = (HV*)NEWSV(502,0);
1537 sv_upgrade((SV *)hv, SVt_PVHV);
1538 xhv = (XPVHV*)SvANY(hv);
1541 #ifndef NODEFAULT_SHAREKEYS
1542 HvSHAREKEYS_on(hv); /* key-sharing on by default */
1545 xhv->xhv_max = 7; /* HvMAX(hv) = 7 (start with 8 buckets) */
1546 xhv->xhv_fill = 0; /* HvFILL(hv) = 0 */
1547 xhv->xhv_pmroot = 0; /* HvPMROOT(hv) = 0 */
1548 (void)hv_iterinit(hv); /* so each() will start off right */
1553 Perl_newHVhv(pTHX_ HV *ohv)
1556 STRLEN hv_max, hv_fill;
1558 if (!ohv || (hv_fill = HvFILL(ohv)) == 0)
1560 hv_max = HvMAX(ohv);
1562 if (!SvMAGICAL((SV *)ohv)) {
1563 /* It's an ordinary hash, so copy it fast. AMS 20010804 */
1565 bool shared = !!HvSHAREKEYS(ohv);
1566 HE **ents, **oents = (HE **)HvARRAY(ohv);
1568 New(0, a, PERL_HV_ARRAY_ALLOC_BYTES(hv_max+1), char);
1571 /* In each bucket... */
1572 for (i = 0; i <= hv_max; i++) {
1573 HE *prev = NULL, *ent = NULL, *oent = oents[i];
1580 /* Copy the linked list of entries. */
1581 for (oent = oents[i]; oent; oent = HeNEXT(oent)) {
1582 U32 hash = HeHASH(oent);
1583 char *key = HeKEY(oent);
1584 STRLEN len = HeKLEN(oent);
1585 int flags = HeKFLAGS(oent);
1588 HeVAL(ent) = newSVsv(HeVAL(oent));
1590 = shared ? share_hek_flags(key, len, hash, flags)
1591 : save_hek_flags(key, len, hash, flags);
1602 HvFILL(hv) = hv_fill;
1603 HvTOTALKEYS(hv) = HvTOTALKEYS(ohv);
1607 /* Iterate over ohv, copying keys and values one at a time. */
1609 I32 riter = HvRITER(ohv);
1610 HE *eiter = HvEITER(ohv);
1612 /* Can we use fewer buckets? (hv_max is always 2^n-1) */
1613 while (hv_max && hv_max + 1 >= hv_fill * 2)
1614 hv_max = hv_max / 2;
1618 while ((entry = hv_iternext_flags(ohv, 0))) {
1619 hv_store_flags(hv, HeKEY(entry), HeKLEN(entry),
1620 newSVsv(HeVAL(entry)), HeHASH(entry),
1623 HvRITER(ohv) = riter;
1624 HvEITER(ohv) = eiter;
1631 Perl_hv_free_ent(pTHX_ HV *hv, register HE *entry)
1638 if (val && isGV(val) && GvCVu(val) && HvNAME(hv))
1639 PL_sub_generation++; /* may be deletion of method from stash */
1641 if (HeKLEN(entry) == HEf_SVKEY) {
1642 SvREFCNT_dec(HeKEY_sv(entry));
1643 Safefree(HeKEY_hek(entry));
1645 else if (HvSHAREKEYS(hv))
1646 unshare_hek(HeKEY_hek(entry));
1648 Safefree(HeKEY_hek(entry));
1653 Perl_hv_delayfree_ent(pTHX_ HV *hv, register HE *entry)
1657 if (isGV(HeVAL(entry)) && GvCVu(HeVAL(entry)) && HvNAME(hv))
1658 PL_sub_generation++; /* may be deletion of method from stash */
1659 sv_2mortal(HeVAL(entry)); /* free between statements */
1660 if (HeKLEN(entry) == HEf_SVKEY) {
1661 sv_2mortal(HeKEY_sv(entry));
1662 Safefree(HeKEY_hek(entry));
1664 else if (HvSHAREKEYS(hv))
1665 unshare_hek(HeKEY_hek(entry));
1667 Safefree(HeKEY_hek(entry));
1672 =for apidoc hv_clear
1674 Clears a hash, making it empty.
1680 Perl_hv_clear(pTHX_ HV *hv)
1682 register XPVHV* xhv;
1686 DEBUG_A(Perl_hv_assert(aTHX_ hv));
1688 xhv = (XPVHV*)SvANY(hv);
1690 if (SvREADONLY(hv) && xhv->xhv_array != NULL) {
1691 /* restricted hash: convert all keys to placeholders */
1694 for (i = 0; i <= (I32) xhv->xhv_max; i++) {
1695 entry = ((HE**)xhv->xhv_array)[i];
1696 for (; entry; entry = HeNEXT(entry)) {
1697 /* not already placeholder */
1698 if (HeVAL(entry) != &PL_sv_placeholder) {
1699 if (HeVAL(entry) && SvREADONLY(HeVAL(entry))) {
1700 SV* keysv = hv_iterkeysv(entry);
1702 "Attempt to delete readonly key '%"SVf"' from a restricted hash",
1705 SvREFCNT_dec(HeVAL(entry));
1706 HeVAL(entry) = &PL_sv_placeholder;
1707 xhv->xhv_placeholders++; /* HvPLACEHOLDERS(hv)++ */
1715 xhv->xhv_placeholders = 0; /* HvPLACEHOLDERS(hv) = 0 */
1716 if (xhv->xhv_array /* HvARRAY(hv) */)
1717 (void)memzero(xhv->xhv_array /* HvARRAY(hv) */,
1718 (xhv->xhv_max+1 /* HvMAX(hv)+1 */) * sizeof(HE*));
1723 HvHASKFLAGS_off(hv);
1728 S_hfreeentries(pTHX_ HV *hv)
1730 register HE **array;
1732 register HE *oentry = Null(HE*);
1743 array = HvARRAY(hv);
1744 /* make everyone else think the array is empty, so that the destructors
1745 * called for freed entries can't recusively mess with us */
1746 HvARRAY(hv) = Null(HE**);
1748 ((XPVHV*) SvANY(hv))->xhv_keys = 0;
1754 entry = HeNEXT(entry);
1755 hv_free_ent(hv, oentry);
1760 entry = array[riter];
1763 HvARRAY(hv) = array;
1764 (void)hv_iterinit(hv);
1768 =for apidoc hv_undef
1776 Perl_hv_undef(pTHX_ HV *hv)
1778 register XPVHV* xhv;
1781 DEBUG_A(Perl_hv_assert(aTHX_ hv));
1782 xhv = (XPVHV*)SvANY(hv);
1784 Safefree(xhv->xhv_array /* HvARRAY(hv) */);
1787 hv_delete(PL_stashcache, HvNAME(hv), strlen(HvNAME(hv)), G_DISCARD);
1788 Safefree(HvNAME(hv));
1791 xhv->xhv_max = 7; /* HvMAX(hv) = 7 (it's a normal hash) */
1792 xhv->xhv_array = 0; /* HvARRAY(hv) = 0 */
1793 xhv->xhv_placeholders = 0; /* HvPLACEHOLDERS(hv) = 0 */
1800 =for apidoc hv_iterinit
1802 Prepares a starting point to traverse a hash table. Returns the number of
1803 keys in the hash (i.e. the same as C<HvKEYS(tb)>). The return value is
1804 currently only meaningful for hashes without tie magic.
1806 NOTE: Before version 5.004_65, C<hv_iterinit> used to return the number of
1807 hash buckets that happen to be in use. If you still need that esoteric
1808 value, you can get it through the macro C<HvFILL(tb)>.
1815 Perl_hv_iterinit(pTHX_ HV *hv)
1817 register XPVHV* xhv;
1821 Perl_croak(aTHX_ "Bad hash");
1822 xhv = (XPVHV*)SvANY(hv);
1823 entry = xhv->xhv_eiter; /* HvEITER(hv) */
1824 if (entry && HvLAZYDEL(hv)) { /* was deleted earlier? */
1826 hv_free_ent(hv, entry);
1828 xhv->xhv_riter = -1; /* HvRITER(hv) = -1 */
1829 xhv->xhv_eiter = Null(HE*); /* HvEITER(hv) = Null(HE*) */
1830 /* used to be xhv->xhv_fill before 5.004_65 */
1831 return XHvTOTALKEYS(xhv);
1834 =for apidoc hv_iternext
1836 Returns entries from a hash iterator. See C<hv_iterinit>.
1838 You may call C<hv_delete> or C<hv_delete_ent> on the hash entry that the
1839 iterator currently points to, without losing your place or invalidating your
1840 iterator. Note that in this case the current entry is deleted from the hash
1841 with your iterator holding the last reference to it. Your iterator is flagged
1842 to free the entry on the next call to C<hv_iternext>, so you must not discard
1843 your iterator immediately else the entry will leak - call C<hv_iternext> to
1844 trigger the resource deallocation.
1850 Perl_hv_iternext(pTHX_ HV *hv)
1852 return hv_iternext_flags(hv, 0);
1856 =for apidoc hv_iternext_flags
1858 Returns entries from a hash iterator. See C<hv_iterinit> and C<hv_iternext>.
1859 The C<flags> value will normally be zero; if HV_ITERNEXT_WANTPLACEHOLDERS is
1860 set the placeholders keys (for restricted hashes) will be returned in addition
1861 to normal keys. By default placeholders are automatically skipped over.
1862 Currently a placeholder is implemented with a value that is
1863 C<&Perl_sv_placeholder>. Note that the implementation of placeholders and
1864 restricted hashes may change, and the implementation currently is
1865 insufficiently abstracted for any change to be tidy.
1871 Perl_hv_iternext_flags(pTHX_ HV *hv, I32 flags)
1873 register XPVHV* xhv;
1879 Perl_croak(aTHX_ "Bad hash");
1880 xhv = (XPVHV*)SvANY(hv);
1881 oldentry = entry = xhv->xhv_eiter; /* HvEITER(hv) */
1883 if ((mg = SvTIED_mg((SV*)hv, PERL_MAGIC_tied))) {
1884 SV *key = sv_newmortal();
1886 sv_setsv(key, HeSVKEY_force(entry));
1887 SvREFCNT_dec(HeSVKEY(entry)); /* get rid of previous key */
1893 /* one HE per MAGICAL hash */
1894 xhv->xhv_eiter = entry = new_HE(); /* HvEITER(hv) = new_HE() */
1896 Newz(54, k, HEK_BASESIZE + sizeof(SV*), char);
1898 HeKEY_hek(entry) = hek;
1899 HeKLEN(entry) = HEf_SVKEY;
1901 magic_nextpack((SV*) hv,mg,key);
1903 /* force key to stay around until next time */
1904 HeSVKEY_set(entry, SvREFCNT_inc(key));
1905 return entry; /* beware, hent_val is not set */
1908 SvREFCNT_dec(HeVAL(entry));
1909 Safefree(HeKEY_hek(entry));
1911 xhv->xhv_eiter = Null(HE*); /* HvEITER(hv) = Null(HE*) */
1914 #ifdef DYNAMIC_ENV_FETCH /* set up %ENV for iteration */
1915 if (!entry && SvRMAGICAL((SV*)hv) && mg_find((SV*)hv, PERL_MAGIC_env))
1919 if (!xhv->xhv_array /* !HvARRAY(hv) */)
1920 Newz(506, xhv->xhv_array /* HvARRAY(hv) */,
1921 PERL_HV_ARRAY_ALLOC_BYTES(xhv->xhv_max+1 /* HvMAX(hv)+1 */),
1923 /* At start of hash, entry is NULL. */
1926 entry = HeNEXT(entry);
1927 if (!(flags & HV_ITERNEXT_WANTPLACEHOLDERS)) {
1929 * Skip past any placeholders -- don't want to include them in
1932 while (entry && HeVAL(entry) == &PL_sv_placeholder) {
1933 entry = HeNEXT(entry);
1938 /* OK. Come to the end of the current list. Grab the next one. */
1940 xhv->xhv_riter++; /* HvRITER(hv)++ */
1941 if (xhv->xhv_riter > (I32)xhv->xhv_max /* HvRITER(hv) > HvMAX(hv) */) {
1942 /* There is no next one. End of the hash. */
1943 xhv->xhv_riter = -1; /* HvRITER(hv) = -1 */
1946 /* entry = (HvARRAY(hv))[HvRITER(hv)]; */
1947 entry = ((HE**)xhv->xhv_array)[xhv->xhv_riter];
1949 if (!(flags & HV_ITERNEXT_WANTPLACEHOLDERS)) {
1950 /* If we have an entry, but it's a placeholder, don't count it.
1952 while (entry && HeVAL(entry) == &PL_sv_placeholder)
1953 entry = HeNEXT(entry);
1955 /* Will loop again if this linked list starts NULL
1956 (for HV_ITERNEXT_WANTPLACEHOLDERS)
1957 or if we run through it and find only placeholders. */
1960 if (oldentry && HvLAZYDEL(hv)) { /* was deleted earlier? */
1962 hv_free_ent(hv, oldentry);
1965 /*if (HvREHASH(hv) && entry && !HeKREHASH(entry))
1966 PerlIO_printf(PerlIO_stderr(), "Awooga %p %p\n", hv, entry);*/
1968 xhv->xhv_eiter = entry; /* HvEITER(hv) = entry */
1973 =for apidoc hv_iterkey
1975 Returns the key from the current position of the hash iterator. See
1982 Perl_hv_iterkey(pTHX_ register HE *entry, I32 *retlen)
1984 if (HeKLEN(entry) == HEf_SVKEY) {
1986 char *p = SvPV(HeKEY_sv(entry), len);
1991 *retlen = HeKLEN(entry);
1992 return HeKEY(entry);
1996 /* unlike hv_iterval(), this always returns a mortal copy of the key */
1998 =for apidoc hv_iterkeysv
2000 Returns the key as an C<SV*> from the current position of the hash
2001 iterator. The return value will always be a mortal copy of the key. Also
2008 Perl_hv_iterkeysv(pTHX_ register HE *entry)
2010 if (HeKLEN(entry) != HEf_SVKEY) {
2011 HEK *hek = HeKEY_hek(entry);
2012 int flags = HEK_FLAGS(hek);
2015 if (flags & HVhek_WASUTF8) {
2017 Andreas would like keys he put in as utf8 to come back as utf8
2019 STRLEN utf8_len = HEK_LEN(hek);
2020 U8 *as_utf8 = bytes_to_utf8 ((U8*)HEK_KEY(hek), &utf8_len);
2022 sv = newSVpvn ((char*)as_utf8, utf8_len);
2024 Safefree (as_utf8); /* bytes_to_utf8() allocates a new string */
2025 } else if (flags & HVhek_REHASH) {
2026 /* We don't have a pointer to the hv, so we have to replicate the
2027 flag into every HEK. This hv is using custom a hasing
2028 algorithm. Hence we can't return a shared string scalar, as
2029 that would contain the (wrong) hash value, and might get passed
2030 into an hv routine with a regular hash */
2032 sv = newSVpvn (HEK_KEY(hek), HEK_LEN(hek));
2036 sv = newSVpvn_share(HEK_KEY(hek),
2037 (HEK_UTF8(hek) ? -HEK_LEN(hek) : HEK_LEN(hek)),
2040 return sv_2mortal(sv);
2042 return sv_mortalcopy(HeKEY_sv(entry));
2046 =for apidoc hv_iterval
2048 Returns the value from the current position of the hash iterator. See
2055 Perl_hv_iterval(pTHX_ HV *hv, register HE *entry)
2057 if (SvRMAGICAL(hv)) {
2058 if (mg_find((SV*)hv, PERL_MAGIC_tied)) {
2059 SV* sv = sv_newmortal();
2060 if (HeKLEN(entry) == HEf_SVKEY)
2061 mg_copy((SV*)hv, sv, (char*)HeKEY_sv(entry), HEf_SVKEY);
2062 else mg_copy((SV*)hv, sv, HeKEY(entry), HeKLEN(entry));
2066 return HeVAL(entry);
2070 =for apidoc hv_iternextsv
2072 Performs an C<hv_iternext>, C<hv_iterkey>, and C<hv_iterval> in one
2079 Perl_hv_iternextsv(pTHX_ HV *hv, char **key, I32 *retlen)
2082 if ( (he = hv_iternext_flags(hv, 0)) == NULL)
2084 *key = hv_iterkey(he, retlen);
2085 return hv_iterval(hv, he);
2089 =for apidoc hv_magic
2091 Adds magic to a hash. See C<sv_magic>.
2097 Perl_hv_magic(pTHX_ HV *hv, GV *gv, int how)
2099 sv_magic((SV*)hv, (SV*)gv, how, Nullch, 0);
2102 #if 0 /* use the macro from hv.h instead */
2105 Perl_sharepvn(pTHX_ const char *sv, I32 len, U32 hash)
2107 return HEK_KEY(share_hek(sv, len, hash));
2112 /* possibly free a shared string if no one has access to it
2113 * len and hash must both be valid for str.
2116 Perl_unsharepvn(pTHX_ const char *str, I32 len, U32 hash)
2118 unshare_hek_or_pvn (NULL, str, len, hash);
2123 Perl_unshare_hek(pTHX_ HEK *hek)
2125 unshare_hek_or_pvn(hek, NULL, 0, 0);
2128 /* possibly free a shared string if no one has access to it
2129 hek if non-NULL takes priority over the other 3, else str, len and hash
2130 are used. If so, len and hash must both be valid for str.
2133 S_unshare_hek_or_pvn(pTHX_ HEK *hek, const char *str, I32 len, U32 hash)
2135 register XPVHV* xhv;
2137 register HE **oentry;
2140 bool is_utf8 = FALSE;
2142 const char *save = str;
2145 hash = HEK_HASH(hek);
2146 } else if (len < 0) {
2147 STRLEN tmplen = -len;
2149 /* See the note in hv_fetch(). --jhi */
2150 str = (char*)bytes_from_utf8((U8*)str, &tmplen, &is_utf8);
2153 k_flags = HVhek_UTF8;
2155 k_flags |= HVhek_WASUTF8 | HVhek_FREEKEY;
2158 /* what follows is the moral equivalent of:
2159 if ((Svp = hv_fetch(PL_strtab, tmpsv, FALSE, hash))) {
2160 if (--*Svp == Nullsv)
2161 hv_delete(PL_strtab, str, len, G_DISCARD, hash);
2163 xhv = (XPVHV*)SvANY(PL_strtab);
2164 /* assert(xhv_array != 0) */
2166 /* oentry = &(HvARRAY(hv))[hash & (I32) HvMAX(hv)]; */
2167 oentry = &((HE**)xhv->xhv_array)[hash & (I32) xhv->xhv_max];
2169 for (entry = *oentry; entry; i=0, oentry = &HeNEXT(entry), entry = *oentry) {
2170 if (HeKEY_hek(entry) != hek)
2176 int flags_masked = k_flags & HVhek_MASK;
2177 for (entry = *oentry; entry; i=0, oentry = &HeNEXT(entry), entry = *oentry) {
2178 if (HeHASH(entry) != hash) /* strings can't be equal */
2180 if (HeKLEN(entry) != len)
2182 if (HeKEY(entry) != str && memNE(HeKEY(entry),str,len)) /* is this it? */
2184 if (HeKFLAGS(entry) != flags_masked)
2192 if (--HeVAL(entry) == Nullsv) {
2193 *oentry = HeNEXT(entry);
2195 xhv->xhv_fill--; /* HvFILL(hv)-- */
2196 Safefree(HeKEY_hek(entry));
2198 xhv->xhv_keys--; /* HvKEYS(hv)-- */
2202 UNLOCK_STRTAB_MUTEX;
2203 if (!found && ckWARN_d(WARN_INTERNAL))
2204 Perl_warner(aTHX_ packWARN(WARN_INTERNAL),
2205 "Attempt to free non-existent shared string '%s'%s",
2206 hek ? HEK_KEY(hek) : str,
2207 (k_flags & HVhek_UTF8) ? " (utf8)" : "");
2208 if (k_flags & HVhek_FREEKEY)
2212 /* get a (constant) string ptr from the global string table
2213 * string will get added if it is not already there.
2214 * len and hash must both be valid for str.
2217 Perl_share_hek(pTHX_ const char *str, I32 len, register U32 hash)
2219 bool is_utf8 = FALSE;
2221 const char *save = str;
2224 STRLEN tmplen = -len;
2226 /* See the note in hv_fetch(). --jhi */
2227 str = (char*)bytes_from_utf8((U8*)str, &tmplen, &is_utf8);
2229 /* If we were able to downgrade here, then than means that we were passed
2230 in a key which only had chars 0-255, but was utf8 encoded. */
2233 /* If we found we were able to downgrade the string to bytes, then
2234 we should flag that it needs upgrading on keys or each. Also flag
2235 that we need share_hek_flags to free the string. */
2237 flags |= HVhek_WASUTF8 | HVhek_FREEKEY;
2240 return share_hek_flags (str, len, hash, flags);
2244 S_share_hek_flags(pTHX_ const char *str, I32 len, register U32 hash, int flags)
2246 register XPVHV* xhv;
2248 register HE **oentry;
2251 int flags_masked = flags & HVhek_MASK;
2253 /* what follows is the moral equivalent of:
2255 if (!(Svp = hv_fetch(PL_strtab, str, len, FALSE)))
2256 hv_store(PL_strtab, str, len, Nullsv, hash);
2258 Can't rehash the shared string table, so not sure if it's worth
2259 counting the number of entries in the linked list
2261 xhv = (XPVHV*)SvANY(PL_strtab);
2262 /* assert(xhv_array != 0) */
2264 /* oentry = &(HvARRAY(hv))[hash & (I32) HvMAX(hv)]; */
2265 oentry = &((HE**)xhv->xhv_array)[hash & (I32) xhv->xhv_max];
2266 for (entry = *oentry; entry; i=0, entry = HeNEXT(entry)) {
2267 if (HeHASH(entry) != hash) /* strings can't be equal */
2269 if (HeKLEN(entry) != len)
2271 if (HeKEY(entry) != str && memNE(HeKEY(entry),str,len)) /* is this it? */
2273 if (HeKFLAGS(entry) != flags_masked)
2280 HeKEY_hek(entry) = save_hek_flags(str, len, hash, flags);
2281 HeVAL(entry) = Nullsv;
2282 HeNEXT(entry) = *oentry;
2284 xhv->xhv_keys++; /* HvKEYS(hv)++ */
2285 if (i) { /* initial entry? */
2286 xhv->xhv_fill++; /* HvFILL(hv)++ */
2287 } else if (xhv->xhv_keys > (IV)xhv->xhv_max /* HvKEYS(hv) > HvMAX(hv) */) {
2292 ++HeVAL(entry); /* use value slot as REFCNT */
2293 UNLOCK_STRTAB_MUTEX;
2295 if (flags & HVhek_FREEKEY)
2298 return HeKEY_hek(entry);
2303 =for apidoc hv_assert
2305 Check that a hash is in an internally consistent state.
2311 Perl_hv_assert(pTHX_ HV *hv)
2315 int placeholders = 0;
2318 I32 riter = HvRITER(hv);
2319 HE *eiter = HvEITER(hv);
2321 (void)hv_iterinit(hv);
2323 while ((entry = hv_iternext_flags(hv, HV_ITERNEXT_WANTPLACEHOLDERS))) {
2324 /* sanity check the values */
2325 if (HeVAL(entry) == &PL_sv_placeholder) {
2330 /* sanity check the keys */
2331 if (HeSVKEY(entry)) {
2332 /* Don't know what to check on SV keys. */
2333 } else if (HeKUTF8(entry)) {
2335 if (HeKWASUTF8(entry)) {
2336 PerlIO_printf(Perl_debug_log,
2337 "hash key has both WASUFT8 and UTF8: '%.*s'\n",
2338 (int) HeKLEN(entry), HeKEY(entry));
2341 } else if (HeKWASUTF8(entry)) {
2345 if (!SvTIED_mg((SV*)hv, PERL_MAGIC_tied)) {
2346 if (HvUSEDKEYS(hv) != real) {
2347 PerlIO_printf(Perl_debug_log, "Count %d key(s), but hash reports %d\n",
2348 (int) real, (int) HvUSEDKEYS(hv));
2351 if (HvPLACEHOLDERS(hv) != placeholders) {
2352 PerlIO_printf(Perl_debug_log,
2353 "Count %d placeholder(s), but hash reports %d\n",
2354 (int) placeholders, (int) HvPLACEHOLDERS(hv));
2358 if (withflags && ! HvHASKFLAGS(hv)) {
2359 PerlIO_printf(Perl_debug_log,
2360 "Hash has HASKFLAGS off but I count %d key(s) with flags\n",
2367 HvRITER(hv) = riter; /* Restore hash iterator state */
2368 HvEITER(hv) = eiter;