3 * Copyright (C) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
4 * 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 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
18 A HV structure represents a Perl hash. It consists mainly of an array
19 of pointers, each of which points to a linked list of HE structures. The
20 array is indexed by the hash function of the key, so each linked list
21 represents all the hash entries with the same hash value. Each HE contains
22 a pointer to the actual value, plus a pointer to a HEK structure which
23 holds the key and hash value.
31 #define PERL_HASH_INTERNAL_ACCESS
34 #define HV_MAX_LENGTH_BEFORE_SPLIT 14
36 static const char S_strtab_error[]
37 = "Cannot modify shared string table in hv_%s";
43 HE* he = (HE*) Perl_get_arena(aTHX_ PERL_ARENA_SIZE, HE_SVSLOT);
44 HE * const heend = &he[PERL_ARENA_SIZE / sizeof(HE) - 1];
46 PL_body_roots[HE_SVSLOT] = he;
48 HeNEXT(he) = (HE*)(he + 1);
56 #define new_HE() (HE*)safemalloc(sizeof(HE))
57 #define del_HE(p) safefree((char*)p)
66 void ** const root = &PL_body_roots[HE_SVSLOT];
76 #define new_HE() new_he()
79 HeNEXT(p) = (HE*)(PL_body_roots[HE_SVSLOT]); \
80 PL_body_roots[HE_SVSLOT] = p; \
88 S_save_hek_flags(const char *str, I32 len, U32 hash, int flags)
90 const int flags_masked = flags & HVhek_MASK;
94 Newx(k, HEK_BASESIZE + len + 2, char);
96 Copy(str, HEK_KEY(hek), len, char);
97 HEK_KEY(hek)[len] = 0;
100 HEK_FLAGS(hek) = (unsigned char)flags_masked | HVhek_UNSHARED;
102 if (flags & HVhek_FREEKEY)
107 /* free the pool of temporary HE/HEK pairs returned by hv_fetch_ent
111 Perl_free_tied_hv_pool(pTHX)
114 HE *he = PL_hv_fetch_ent_mh;
117 Safefree(HeKEY_hek(he));
121 PL_hv_fetch_ent_mh = NULL;
124 #if defined(USE_ITHREADS)
126 Perl_hek_dup(pTHX_ HEK *source, CLONE_PARAMS* param)
128 HEK *shared = (HEK*)ptr_table_fetch(PL_ptr_table, source);
130 PERL_UNUSED_ARG(param);
133 /* We already shared this hash key. */
134 (void)share_hek_hek(shared);
138 = share_hek_flags(HEK_KEY(source), HEK_LEN(source),
139 HEK_HASH(source), HEK_FLAGS(source));
140 ptr_table_store(PL_ptr_table, source, shared);
146 Perl_he_dup(pTHX_ const HE *e, bool shared, CLONE_PARAMS* param)
152 /* look for it in the table first */
153 ret = (HE*)ptr_table_fetch(PL_ptr_table, e);
157 /* create anew and remember what it is */
159 ptr_table_store(PL_ptr_table, e, ret);
161 HeNEXT(ret) = he_dup(HeNEXT(e),shared, param);
162 if (HeKLEN(e) == HEf_SVKEY) {
164 Newx(k, HEK_BASESIZE + sizeof(SV*), char);
165 HeKEY_hek(ret) = (HEK*)k;
166 HeKEY_sv(ret) = SvREFCNT_inc(sv_dup(HeKEY_sv(e), param));
169 /* This is hek_dup inlined, which seems to be important for speed
171 HEK * const source = HeKEY_hek(e);
172 HEK *shared = (HEK*)ptr_table_fetch(PL_ptr_table, source);
175 /* We already shared this hash key. */
176 (void)share_hek_hek(shared);
180 = share_hek_flags(HEK_KEY(source), HEK_LEN(source),
181 HEK_HASH(source), HEK_FLAGS(source));
182 ptr_table_store(PL_ptr_table, source, shared);
184 HeKEY_hek(ret) = shared;
187 HeKEY_hek(ret) = save_hek_flags(HeKEY(e), HeKLEN(e), HeHASH(e),
189 HeVAL(ret) = SvREFCNT_inc(sv_dup(HeVAL(e), param));
192 #endif /* USE_ITHREADS */
195 S_hv_notallowed(pTHX_ int flags, const char *key, I32 klen,
198 SV * const sv = sv_newmortal();
199 if (!(flags & HVhek_FREEKEY)) {
200 sv_setpvn(sv, key, klen);
203 /* Need to free saved eventually assign to mortal SV */
204 /* XXX is this line an error ???: SV *sv = sv_newmortal(); */
205 sv_usepvn(sv, (char *) key, klen);
207 if (flags & HVhek_UTF8) {
210 Perl_croak(aTHX_ msg, SVfARG(sv));
213 /* (klen == HEf_SVKEY) is special for MAGICAL hv entries, meaning key slot
219 Stores an SV in a hash. The hash key is specified as C<key> and C<klen> is
220 the length of the key. The C<hash> parameter is the precomputed hash
221 value; if it is zero then Perl will compute it. The return value will be
222 NULL if the operation failed or if the value did not need to be actually
223 stored within the hash (as in the case of tied hashes). Otherwise it can
224 be dereferenced to get the original C<SV*>. Note that the caller is
225 responsible for suitably incrementing the reference count of C<val> before
226 the call, and decrementing it if the function returned NULL. Effectively
227 a successful hv_store takes ownership of one reference to C<val>. This is
228 usually what you want; a newly created SV has a reference count of one, so
229 if all your code does is create SVs then store them in a hash, hv_store
230 will own the only reference to the new SV, and your code doesn't need to do
231 anything further to tidy up. hv_store is not implemented as a call to
232 hv_store_ent, and does not create a temporary SV for the key, so if your
233 key data is not already in SV form then use hv_store in preference to
236 See L<perlguts/"Understanding the Magic of Tied Hashes and Arrays"> for more
237 information on how to use this function on tied hashes.
239 =for apidoc hv_store_ent
241 Stores C<val> in a hash. The hash key is specified as C<key>. The C<hash>
242 parameter is the precomputed hash value; if it is zero then Perl will
243 compute it. The return value is the new hash entry so created. It will be
244 NULL if the operation failed or if the value did not need to be actually
245 stored within the hash (as in the case of tied hashes). Otherwise the
246 contents of the return value can be accessed using the C<He?> macros
247 described here. Note that the caller is responsible for suitably
248 incrementing the reference count of C<val> before the call, and
249 decrementing it if the function returned NULL. Effectively a successful
250 hv_store_ent takes ownership of one reference to C<val>. This is
251 usually what you want; a newly created SV has a reference count of one, so
252 if all your code does is create SVs then store them in a hash, hv_store
253 will own the only reference to the new SV, and your code doesn't need to do
254 anything further to tidy up. Note that hv_store_ent only reads the C<key>;
255 unlike C<val> it does not take ownership of it, so maintaining the correct
256 reference count on C<key> is entirely the caller's responsibility. hv_store
257 is not implemented as a call to hv_store_ent, and does not create a temporary
258 SV for the key, so if your key data is not already in SV form then use
259 hv_store in preference to hv_store_ent.
261 See L<perlguts/"Understanding the Magic of Tied Hashes and Arrays"> for more
262 information on how to use this function on tied hashes.
264 =for apidoc hv_exists
266 Returns a boolean indicating whether the specified hash key exists. The
267 C<klen> is the length of the key.
271 Returns the SV which corresponds to the specified key in the hash. The
272 C<klen> is the length of the key. If C<lval> is set then the fetch will be
273 part of a store. Check that the return value is non-null before
274 dereferencing it to an C<SV*>.
276 See L<perlguts/"Understanding the Magic of Tied Hashes and Arrays"> for more
277 information on how to use this function on tied hashes.
279 =for apidoc hv_exists_ent
281 Returns a boolean indicating whether the specified hash key exists. C<hash>
282 can be a valid precomputed hash value, or 0 to ask for it to be
288 /* returns an HE * structure with the all fields set */
289 /* note that hent_val will be a mortal sv for MAGICAL hashes */
291 =for apidoc hv_fetch_ent
293 Returns the hash entry which corresponds to the specified key in the hash.
294 C<hash> must be a valid precomputed hash number for the given C<key>, or 0
295 if you want the function to compute it. IF C<lval> is set then the fetch
296 will be part of a store. Make sure the return value is non-null before
297 accessing it. The return value when C<tb> is a tied hash is a pointer to a
298 static location, so be sure to make a copy of the structure if you need to
301 See L<perlguts/"Understanding the Magic of Tied Hashes and Arrays"> for more
302 information on how to use this function on tied hashes.
307 /* Common code for hv_delete()/hv_exists()/hv_fetch()/hv_store() */
309 Perl_hv_common_key_len(pTHX_ HV *hv, const char *key, I32 klen_i32,
310 const int action, SV *val, const U32 hash)
322 return hv_common(hv, NULL, key, klen, flags, action, val, hash);
326 Perl_hv_common(pTHX_ HV *hv, SV *keysv, const char *key, STRLEN klen,
327 int flags, int action, SV *val, register U32 hash)
336 const int return_svp = action & HV_FETCH_JUST_SV;
340 if (SvTYPE(hv) == SVTYPEMASK)
343 assert(SvTYPE(hv) == SVt_PVHV);
345 if (SvSMAGICAL(hv) && SvGMAGICAL(hv) && !(action & HV_DISABLE_UVAR_XKEY)) {
347 if ((mg = mg_find((SV*)hv, PERL_MAGIC_uvar))) {
348 struct ufuncs * const uf = (struct ufuncs *)mg->mg_ptr;
349 if (uf->uf_set == NULL) {
350 SV* obj = mg->mg_obj;
353 keysv = newSVpvn_flags(key, klen, SVs_TEMP |
354 ((flags & HVhek_UTF8)
358 mg->mg_obj = keysv; /* pass key */
359 uf->uf_index = action; /* pass action */
360 magic_getuvar((SV*)hv, mg);
361 keysv = mg->mg_obj; /* may have changed */
364 /* If the key may have changed, then we need to invalidate
365 any passed-in computed hash value. */
371 if (flags & HVhek_FREEKEY)
373 key = SvPV_const(keysv, klen);
375 is_utf8 = (SvUTF8(keysv) != 0);
377 is_utf8 = ((flags & HVhek_UTF8) ? TRUE : FALSE);
380 if (action & HV_DELETE) {
381 return (void *) hv_delete_common(hv, keysv, key, klen,
382 flags | (is_utf8 ? HVhek_UTF8 : 0),
386 xhv = (XPVHV*)SvANY(hv);
388 if (SvRMAGICAL(hv) && !(action & (HV_FETCH_ISSTORE|HV_FETCH_ISEXISTS))) {
389 if ( mg_find((SV*)hv, PERL_MAGIC_tied) || SvGMAGICAL((SV*)hv))
391 /* FIXME should be able to skimp on the HE/HEK here when
392 HV_FETCH_JUST_SV is true. */
394 keysv = newSVpvn_utf8(key, klen, is_utf8);
396 keysv = newSVsv(keysv);
399 mg_copy((SV*)hv, sv, (char *)keysv, HEf_SVKEY);
401 /* grab a fake HE/HEK pair from the pool or make a new one */
402 entry = PL_hv_fetch_ent_mh;
404 PL_hv_fetch_ent_mh = HeNEXT(entry);
408 Newx(k, HEK_BASESIZE + sizeof(SV*), char);
409 HeKEY_hek(entry) = (HEK*)k;
411 HeNEXT(entry) = NULL;
412 HeSVKEY_set(entry, keysv);
414 sv_upgrade(sv, SVt_PVLV);
416 /* so we can free entry when freeing sv */
417 LvTARG(sv) = (SV*)entry;
419 /* XXX remove at some point? */
420 if (flags & HVhek_FREEKEY)
424 return entry ? (void *) &HeVAL(entry) : NULL;
426 return (void *) entry;
428 #ifdef ENV_IS_CASELESS
429 else if (mg_find((SV*)hv, PERL_MAGIC_env)) {
431 for (i = 0; i < klen; ++i)
432 if (isLOWER(key[i])) {
433 /* Would be nice if we had a routine to do the
434 copy and upercase in a single pass through. */
435 const char * const nkey = strupr(savepvn(key,klen));
436 /* Note that this fetch is for nkey (the uppercased
437 key) whereas the store is for key (the original) */
438 void *result = hv_common(hv, NULL, nkey, klen,
439 HVhek_FREEKEY, /* free nkey */
440 0 /* non-LVAL fetch */
441 | HV_DISABLE_UVAR_XKEY
444 0 /* compute hash */);
445 if (!result && (action & HV_FETCH_LVALUE)) {
446 /* This call will free key if necessary.
447 Do it this way to encourage compiler to tail
449 result = hv_common(hv, keysv, key, klen, flags,
451 | HV_DISABLE_UVAR_XKEY
455 if (flags & HVhek_FREEKEY)
463 else if (SvRMAGICAL(hv) && (action & HV_FETCH_ISEXISTS)) {
464 if (mg_find((SV*)hv, PERL_MAGIC_tied) || SvGMAGICAL((SV*)hv)) {
465 /* I don't understand why hv_exists_ent has svret and sv,
466 whereas hv_exists only had one. */
467 SV * const svret = sv_newmortal();
470 if (keysv || is_utf8) {
472 keysv = newSVpvn_utf8(key, klen, TRUE);
474 keysv = newSVsv(keysv);
476 mg_copy((SV*)hv, sv, (char *)sv_2mortal(keysv), HEf_SVKEY);
478 mg_copy((SV*)hv, sv, key, klen);
480 if (flags & HVhek_FREEKEY)
482 magic_existspack(svret, mg_find(sv, PERL_MAGIC_tiedelem));
483 /* This cast somewhat evil, but I'm merely using NULL/
484 not NULL to return the boolean exists.
485 And I know hv is not NULL. */
486 return SvTRUE(svret) ? (void *)hv : NULL;
488 #ifdef ENV_IS_CASELESS
489 else if (mg_find((SV*)hv, PERL_MAGIC_env)) {
490 /* XXX This code isn't UTF8 clean. */
491 char * const keysave = (char * const)key;
492 /* Will need to free this, so set FREEKEY flag. */
493 key = savepvn(key,klen);
494 key = (const char*)strupr((char*)key);
499 if (flags & HVhek_FREEKEY) {
502 flags |= HVhek_FREEKEY;
506 else if (action & HV_FETCH_ISSTORE) {
509 hv_magic_check (hv, &needs_copy, &needs_store);
511 const bool save_taint = PL_tainted;
512 if (keysv || is_utf8) {
514 keysv = newSVpvn_utf8(key, klen, TRUE);
517 PL_tainted = SvTAINTED(keysv);
518 keysv = sv_2mortal(newSVsv(keysv));
519 mg_copy((SV*)hv, val, (char*)keysv, HEf_SVKEY);
521 mg_copy((SV*)hv, val, key, klen);
524 TAINT_IF(save_taint);
526 if (flags & HVhek_FREEKEY)
530 #ifdef ENV_IS_CASELESS
531 else if (mg_find((SV*)hv, PERL_MAGIC_env)) {
532 /* XXX This code isn't UTF8 clean. */
533 const char *keysave = key;
534 /* Will need to free this, so set FREEKEY flag. */
535 key = savepvn(key,klen);
536 key = (const char*)strupr((char*)key);
541 if (flags & HVhek_FREEKEY) {
544 flags |= HVhek_FREEKEY;
552 if ((action & (HV_FETCH_LVALUE | HV_FETCH_ISSTORE))
553 #ifdef DYNAMIC_ENV_FETCH /* if it's an %ENV lookup, we may get it on the fly */
554 || (SvRMAGICAL((SV*)hv) && mg_find((SV*)hv, PERL_MAGIC_env))
559 PERL_HV_ARRAY_ALLOC_BYTES(xhv->xhv_max+1 /* HvMAX(hv)+1 */),
561 HvARRAY(hv) = (HE**)array;
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 char * const keysave = (char *)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))) {
602 hash = SvSHARED_HASH(keysv);
604 PERL_HASH(hash, key, klen);
608 masked_flags = (flags & HVhek_MASK);
610 #ifdef DYNAMIC_ENV_FETCH
611 if (!HvARRAY(hv)) entry = NULL;
615 entry = (HvARRAY(hv))[hash & (I32) HvMAX(hv)];
617 for (; entry; entry = HeNEXT(entry)) {
618 if (HeHASH(entry) != hash) /* strings can't be equal */
620 if (HeKLEN(entry) != (I32)klen)
622 if (HeKEY(entry) != key && memNE(HeKEY(entry),key,klen)) /* is this it? */
624 if ((HeKFLAGS(entry) ^ masked_flags) & HVhek_UTF8)
627 if (action & (HV_FETCH_LVALUE|HV_FETCH_ISSTORE)) {
628 if (HeKFLAGS(entry) != masked_flags) {
629 /* We match if HVhek_UTF8 bit in our flags and hash key's
630 match. But if entry was set previously with HVhek_WASUTF8
631 and key now doesn't (or vice versa) then we should change
632 the key's flag, as this is assignment. */
633 if (HvSHAREKEYS(hv)) {
634 /* Need to swap the key we have for a key with the flags we
635 need. As keys are shared we can't just write to the
636 flag, so we share the new one, unshare the old one. */
637 HEK * const new_hek = share_hek_flags(key, klen, hash,
639 unshare_hek (HeKEY_hek(entry));
640 HeKEY_hek(entry) = new_hek;
642 else if (hv == PL_strtab) {
643 /* PL_strtab is usually the only hash without HvSHAREKEYS,
644 so putting this test here is cheap */
645 if (flags & HVhek_FREEKEY)
647 Perl_croak(aTHX_ S_strtab_error,
648 action & HV_FETCH_LVALUE ? "fetch" : "store");
651 HeKFLAGS(entry) = masked_flags;
652 if (masked_flags & HVhek_ENABLEHVKFLAGS)
655 if (HeVAL(entry) == &PL_sv_placeholder) {
656 /* yes, can store into placeholder slot */
657 if (action & HV_FETCH_LVALUE) {
659 /* This preserves behaviour with the old hv_fetch
660 implementation which at this point would bail out
661 with a break; (at "if we find a placeholder, we
662 pretend we haven't found anything")
664 That break mean that if a placeholder were found, it
665 caused a call into hv_store, which in turn would
666 check magic, and if there is no magic end up pretty
667 much back at this point (in hv_store's code). */
670 /* LVAL fetch which actaully needs a store. */
672 HvPLACEHOLDERS(hv)--;
675 if (val != &PL_sv_placeholder)
676 HvPLACEHOLDERS(hv)--;
679 } else if (action & HV_FETCH_ISSTORE) {
680 SvREFCNT_dec(HeVAL(entry));
683 } else if (HeVAL(entry) == &PL_sv_placeholder) {
684 /* if we find a placeholder, we pretend we haven't found
688 if (flags & HVhek_FREEKEY)
691 return entry ? (void *) &HeVAL(entry) : NULL;
695 #ifdef DYNAMIC_ENV_FETCH /* %ENV lookup? If so, try to fetch the value now */
696 if (!(action & HV_FETCH_ISSTORE)
697 && SvRMAGICAL((SV*)hv) && mg_find((SV*)hv, PERL_MAGIC_env)) {
699 const char * const env = PerlEnv_ENVgetenv_len(key,&len);
701 sv = newSVpvn(env,len);
703 return hv_common(hv, keysv, key, klen, flags,
704 HV_FETCH_ISSTORE|HV_DISABLE_UVAR_XKEY|return_svp,
710 if (!entry && SvREADONLY(hv) && !(action & HV_FETCH_ISEXISTS)) {
711 hv_notallowed(flags, key, klen,
712 "Attempt to access disallowed key '%"SVf"' in"
713 " a restricted hash");
715 if (!(action & (HV_FETCH_LVALUE|HV_FETCH_ISSTORE))) {
716 /* Not doing some form of store, so return failure. */
717 if (flags & HVhek_FREEKEY)
721 if (action & HV_FETCH_LVALUE) {
724 /* At this point the old hv_fetch code would call to hv_store,
725 which in turn might do some tied magic. So we need to make that
726 magic check happen. */
727 /* gonna assign to this, so it better be there */
728 /* If a fetch-as-store fails on the fetch, then the action is to
729 recurse once into "hv_store". If we didn't do this, then that
730 recursive call would call the key conversion routine again.
731 However, as we replace the original key with the converted
732 key, this would result in a double conversion, which would show
733 up as a bug if the conversion routine is not idempotent. */
734 return hv_common(hv, keysv, key, klen, flags,
735 HV_FETCH_ISSTORE|HV_DISABLE_UVAR_XKEY|return_svp,
737 /* XXX Surely that could leak if the fetch-was-store fails?
738 Just like the hv_fetch. */
742 /* Welcome to hv_store... */
745 /* Not sure if we can get here. I think the only case of oentry being
746 NULL is for %ENV with dynamic env fetch. But that should disappear
747 with magic in the previous code. */
750 PERL_HV_ARRAY_ALLOC_BYTES(xhv->xhv_max+1 /* HvMAX(hv)+1 */),
752 HvARRAY(hv) = (HE**)array;
755 oentry = &(HvARRAY(hv))[hash & (I32) xhv->xhv_max];
758 /* share_hek_flags will do the free for us. This might be considered
761 HeKEY_hek(entry) = share_hek_flags(key, klen, hash, flags);
762 else if (hv == PL_strtab) {
763 /* PL_strtab is usually the only hash without HvSHAREKEYS, so putting
764 this test here is cheap */
765 if (flags & HVhek_FREEKEY)
767 Perl_croak(aTHX_ S_strtab_error,
768 action & HV_FETCH_LVALUE ? "fetch" : "store");
770 else /* gotta do the real thing */
771 HeKEY_hek(entry) = save_hek_flags(key, klen, hash, flags);
773 HeNEXT(entry) = *oentry;
776 if (val == &PL_sv_placeholder)
777 HvPLACEHOLDERS(hv)++;
778 if (masked_flags & HVhek_ENABLEHVKFLAGS)
782 const HE *counter = HeNEXT(entry);
784 xhv->xhv_keys++; /* HvTOTALKEYS(hv)++ */
785 if (!counter) { /* initial entry? */
786 xhv->xhv_fill++; /* HvFILL(hv)++ */
787 } else if (xhv->xhv_keys > (IV)xhv->xhv_max) {
789 } else if(!HvREHASH(hv)) {
792 while ((counter = HeNEXT(counter)))
795 if (n_links > HV_MAX_LENGTH_BEFORE_SPLIT) {
796 /* Use only the old HvKEYS(hv) > HvMAX(hv) condition to limit
797 bucket splits on a rehashed hash, as we're not going to
798 split it again, and if someone is lucky (evil) enough to
799 get all the keys in one list they could exhaust our memory
800 as we repeatedly double the number of buckets on every
801 entry. Linear search feels a less worse thing to do. */
808 return entry ? (void *) &HeVAL(entry) : NULL;
810 return (void *) entry;
814 S_hv_magic_check(HV *hv, bool *needs_copy, bool *needs_store)
816 const MAGIC *mg = SvMAGIC(hv);
820 if (isUPPER(mg->mg_type)) {
822 if (mg->mg_type == PERL_MAGIC_tied) {
823 *needs_store = FALSE;
824 return; /* We've set all there is to set. */
827 mg = mg->mg_moremagic;
832 =for apidoc hv_scalar
834 Evaluates the hash in scalar context and returns the result. Handles magic when the hash is tied.
840 Perl_hv_scalar(pTHX_ HV *hv)
844 if (SvRMAGICAL(hv)) {
845 MAGIC * const mg = mg_find((SV*)hv, PERL_MAGIC_tied);
847 return magic_scalarpack(hv, mg);
852 Perl_sv_setpvf(aTHX_ sv, "%ld/%ld",
853 (long)HvFILL(hv), (long)HvMAX(hv) + 1);
861 =for apidoc hv_delete
863 Deletes a key/value pair in the hash. The value SV is removed from the
864 hash and returned to the caller. The C<klen> is the length of the key.
865 The C<flags> value will normally be zero; if set to G_DISCARD then NULL
868 =for apidoc hv_delete_ent
870 Deletes a key/value pair in the hash. The value SV is removed from the
871 hash and returned to the caller. The C<flags> value will normally be zero;
872 if set to G_DISCARD then NULL will be returned. C<hash> can be a valid
873 precomputed hash value, or 0 to ask for it to be computed.
879 S_hv_delete_common(pTHX_ HV *hv, SV *keysv, const char *key, STRLEN klen,
880 int k_flags, I32 d_flags, U32 hash)
885 register HE **oentry;
886 HE *const *first_entry;
887 bool is_utf8 = (k_flags & HVhek_UTF8) ? TRUE : FALSE;
890 if (SvRMAGICAL(hv)) {
893 hv_magic_check (hv, &needs_copy, &needs_store);
897 entry = (HE *) hv_common(hv, keysv, key, klen,
898 k_flags & ~HVhek_FREEKEY,
899 HV_FETCH_LVALUE|HV_DISABLE_UVAR_XKEY,
901 sv = entry ? HeVAL(entry) : NULL;
907 if (mg_find(sv, PERL_MAGIC_tiedelem)) {
908 /* No longer an element */
909 sv_unmagic(sv, PERL_MAGIC_tiedelem);
912 return NULL; /* element cannot be deleted */
914 #ifdef ENV_IS_CASELESS
915 else if (mg_find((SV*)hv, PERL_MAGIC_env)) {
916 /* XXX This code isn't UTF8 clean. */
917 keysv = newSVpvn_flags(key, klen, SVs_TEMP);
918 if (k_flags & HVhek_FREEKEY) {
921 key = strupr(SvPVX(keysv));
930 xhv = (XPVHV*)SvANY(hv);
935 const char * const keysave = key;
936 key = (char*)bytes_from_utf8((U8*)key, &klen, &is_utf8);
939 k_flags |= HVhek_UTF8;
941 k_flags &= ~HVhek_UTF8;
942 if (key != keysave) {
943 if (k_flags & HVhek_FREEKEY) {
944 /* This shouldn't happen if our caller does what we expect,
945 but strictly the API allows it. */
948 k_flags |= HVhek_WASUTF8 | HVhek_FREEKEY;
950 HvHASKFLAGS_on((SV*)hv);
954 PERL_HASH_INTERNAL(hash, key, klen);
956 if (keysv && (SvIsCOW_shared_hash(keysv))) {
957 hash = SvSHARED_HASH(keysv);
959 PERL_HASH(hash, key, klen);
963 masked_flags = (k_flags & HVhek_MASK);
965 first_entry = oentry = &(HvARRAY(hv))[hash & (I32) HvMAX(hv)];
967 for (; entry; oentry = &HeNEXT(entry), entry = *oentry) {
969 if (HeHASH(entry) != hash) /* strings can't be equal */
971 if (HeKLEN(entry) != (I32)klen)
973 if (HeKEY(entry) != key && memNE(HeKEY(entry),key,klen)) /* is this it? */
975 if ((HeKFLAGS(entry) ^ masked_flags) & HVhek_UTF8)
978 if (hv == PL_strtab) {
979 if (k_flags & HVhek_FREEKEY)
981 Perl_croak(aTHX_ S_strtab_error, "delete");
984 /* if placeholder is here, it's already been deleted.... */
985 if (HeVAL(entry) == &PL_sv_placeholder) {
986 if (k_flags & HVhek_FREEKEY)
990 if (SvREADONLY(hv) && HeVAL(entry) && SvREADONLY(HeVAL(entry))) {
991 hv_notallowed(k_flags, key, klen,
992 "Attempt to delete readonly key '%"SVf"' from"
993 " a restricted hash");
995 if (k_flags & HVhek_FREEKEY)
998 if (d_flags & G_DISCARD)
1001 sv = sv_2mortal(HeVAL(entry));
1002 HeVAL(entry) = &PL_sv_placeholder;
1006 * If a restricted hash, rather than really deleting the entry, put
1007 * a placeholder there. This marks the key as being "approved", so
1008 * we can still access via not-really-existing key without raising
1011 if (SvREADONLY(hv)) {
1012 SvREFCNT_dec(HeVAL(entry));
1013 HeVAL(entry) = &PL_sv_placeholder;
1014 /* We'll be saving this slot, so the number of allocated keys
1015 * doesn't go down, but the number placeholders goes up */
1016 HvPLACEHOLDERS(hv)++;
1018 *oentry = HeNEXT(entry);
1020 xhv->xhv_fill--; /* HvFILL(hv)-- */
1022 if (SvOOK(hv) && entry == HvAUX(hv)->xhv_eiter /* HvEITER(hv) */)
1025 hv_free_ent(hv, entry);
1026 xhv->xhv_keys--; /* HvTOTALKEYS(hv)-- */
1027 if (xhv->xhv_keys == 0)
1028 HvHASKFLAGS_off(hv);
1032 if (SvREADONLY(hv)) {
1033 hv_notallowed(k_flags, key, klen,
1034 "Attempt to delete disallowed key '%"SVf"' from"
1035 " a restricted hash");
1038 if (k_flags & HVhek_FREEKEY)
1044 S_hsplit(pTHX_ HV *hv)
1047 register XPVHV* const xhv = (XPVHV*)SvANY(hv);
1048 const I32 oldsize = (I32) xhv->xhv_max+1; /* HvMAX(hv)+1 (sick) */
1049 register I32 newsize = oldsize * 2;
1051 char *a = (char*) HvARRAY(hv);
1053 register HE **oentry;
1054 int longest_chain = 0;
1057 /*PerlIO_printf(PerlIO_stderr(), "hsplit called for %p which had %d\n",
1058 (void*)hv, (int) oldsize);*/
1060 if (HvPLACEHOLDERS_get(hv) && !SvREADONLY(hv)) {
1061 /* Can make this clear any placeholders first for non-restricted hashes,
1062 even though Storable rebuilds restricted hashes by putting in all the
1063 placeholders (first) before turning on the readonly flag, because
1064 Storable always pre-splits the hash. */
1065 hv_clear_placeholders(hv);
1069 #if defined(STRANGE_MALLOC) || defined(MYMALLOC)
1070 Renew(a, PERL_HV_ARRAY_ALLOC_BYTES(newsize)
1071 + (SvOOK(hv) ? sizeof(struct xpvhv_aux) : 0), char);
1077 Copy(&a[oldsize * sizeof(HE*)], &a[newsize * sizeof(HE*)], 1, struct xpvhv_aux);
1080 Newx(a, PERL_HV_ARRAY_ALLOC_BYTES(newsize)
1081 + (SvOOK(hv) ? sizeof(struct xpvhv_aux) : 0), char);
1086 Copy(HvARRAY(hv), a, oldsize * sizeof(HE*), char);
1088 Copy(HvAUX(hv), &a[newsize * sizeof(HE*)], 1, struct xpvhv_aux);
1090 if (oldsize >= 64) {
1091 offer_nice_chunk(HvARRAY(hv),
1092 PERL_HV_ARRAY_ALLOC_BYTES(oldsize)
1093 + (SvOOK(hv) ? sizeof(struct xpvhv_aux) : 0));
1096 Safefree(HvARRAY(hv));
1100 Zero(&a[oldsize * sizeof(HE*)], (newsize-oldsize) * sizeof(HE*), char); /* zero 2nd half*/
1101 xhv->xhv_max = --newsize; /* HvMAX(hv) = --newsize */
1102 HvARRAY(hv) = (HE**) a;
1105 for (i=0; i<oldsize; i++,aep++) {
1106 int left_length = 0;
1107 int right_length = 0;
1111 if (!*aep) /* non-existent */
1114 for (oentry = aep, entry = *aep; entry; entry = *oentry) {
1115 if ((HeHASH(entry) & newsize) != (U32)i) {
1116 *oentry = HeNEXT(entry);
1117 HeNEXT(entry) = *bep;
1119 xhv->xhv_fill++; /* HvFILL(hv)++ */
1125 oentry = &HeNEXT(entry);
1129 if (!*aep) /* everything moved */
1130 xhv->xhv_fill--; /* HvFILL(hv)-- */
1131 /* I think we don't actually need to keep track of the longest length,
1132 merely flag if anything is too long. But for the moment while
1133 developing this code I'll track it. */
1134 if (left_length > longest_chain)
1135 longest_chain = left_length;
1136 if (right_length > longest_chain)
1137 longest_chain = right_length;
1141 /* Pick your policy for "hashing isn't working" here: */
1142 if (longest_chain <= HV_MAX_LENGTH_BEFORE_SPLIT /* split worked? */
1147 if (hv == PL_strtab) {
1148 /* Urg. Someone is doing something nasty to the string table.
1153 /* Awooga. Awooga. Pathological data. */
1154 /*PerlIO_printf(PerlIO_stderr(), "%p %d of %d with %d/%d buckets\n", (void*)hv,
1155 longest_chain, HvTOTALKEYS(hv), HvFILL(hv), 1+HvMAX(hv));*/
1158 Newxz(a, PERL_HV_ARRAY_ALLOC_BYTES(newsize)
1159 + (SvOOK(hv) ? sizeof(struct xpvhv_aux) : 0), char);
1161 Copy(HvAUX(hv), &a[newsize * sizeof(HE*)], 1, struct xpvhv_aux);
1164 was_shared = HvSHAREKEYS(hv);
1167 HvSHAREKEYS_off(hv);
1172 for (i=0; i<newsize; i++,aep++) {
1173 register HE *entry = *aep;
1175 /* We're going to trash this HE's next pointer when we chain it
1176 into the new hash below, so store where we go next. */
1177 HE * const next = HeNEXT(entry);
1182 PERL_HASH_INTERNAL(hash, HeKEY(entry), HeKLEN(entry));
1187 = save_hek_flags(HeKEY(entry), HeKLEN(entry),
1188 hash, HeKFLAGS(entry));
1189 unshare_hek (HeKEY_hek(entry));
1190 HeKEY_hek(entry) = new_hek;
1192 /* Not shared, so simply write the new hash in. */
1193 HeHASH(entry) = hash;
1195 /*PerlIO_printf(PerlIO_stderr(), "%d ", HeKFLAGS(entry));*/
1196 HEK_REHASH_on(HeKEY_hek(entry));
1197 /*PerlIO_printf(PerlIO_stderr(), "%d\n", HeKFLAGS(entry));*/
1199 /* Copy oentry to the correct new chain. */
1200 bep = ((HE**)a) + (hash & (I32) xhv->xhv_max);
1202 xhv->xhv_fill++; /* HvFILL(hv)++ */
1203 HeNEXT(entry) = *bep;
1209 Safefree (HvARRAY(hv));
1210 HvARRAY(hv) = (HE **)a;
1214 Perl_hv_ksplit(pTHX_ HV *hv, IV newmax)
1217 register XPVHV* xhv = (XPVHV*)SvANY(hv);
1218 const I32 oldsize = (I32) xhv->xhv_max+1; /* HvMAX(hv)+1 (sick) */
1219 register I32 newsize;
1224 register HE **oentry;
1226 newsize = (I32) newmax; /* possible truncation here */
1227 if (newsize != newmax || newmax <= oldsize)
1229 while ((newsize & (1 + ~newsize)) != newsize) {
1230 newsize &= ~(newsize & (1 + ~newsize)); /* get proper power of 2 */
1232 if (newsize < newmax)
1234 if (newsize < newmax)
1235 return; /* overflow detection */
1237 a = (char *) HvARRAY(hv);
1240 #if defined(STRANGE_MALLOC) || defined(MYMALLOC)
1241 Renew(a, PERL_HV_ARRAY_ALLOC_BYTES(newsize)
1242 + (SvOOK(hv) ? sizeof(struct xpvhv_aux) : 0), char);
1248 Copy(&a[oldsize * sizeof(HE*)], &a[newsize * sizeof(HE*)], 1, struct xpvhv_aux);
1251 Newx(a, PERL_HV_ARRAY_ALLOC_BYTES(newsize)
1252 + (SvOOK(hv) ? sizeof(struct xpvhv_aux) : 0), char);
1257 Copy(HvARRAY(hv), a, oldsize * sizeof(HE*), char);
1259 Copy(HvAUX(hv), &a[newsize * sizeof(HE*)], 1, struct xpvhv_aux);
1261 if (oldsize >= 64) {
1262 offer_nice_chunk(HvARRAY(hv),
1263 PERL_HV_ARRAY_ALLOC_BYTES(oldsize)
1264 + (SvOOK(hv) ? sizeof(struct xpvhv_aux) : 0));
1267 Safefree(HvARRAY(hv));
1270 Zero(&a[oldsize * sizeof(HE*)], (newsize-oldsize) * sizeof(HE*), char); /* zero 2nd half*/
1273 Newxz(a, PERL_HV_ARRAY_ALLOC_BYTES(newsize), char);
1275 xhv->xhv_max = --newsize; /* HvMAX(hv) = --newsize */
1276 HvARRAY(hv) = (HE **) a;
1277 if (!xhv->xhv_fill /* !HvFILL(hv) */) /* skip rest if no entries */
1281 for (i=0; i<oldsize; i++,aep++) {
1282 if (!*aep) /* non-existent */
1284 for (oentry = aep, entry = *aep; entry; entry = *oentry) {
1285 register I32 j = (HeHASH(entry) & newsize);
1289 *oentry = HeNEXT(entry);
1290 if (!(HeNEXT(entry) = aep[j]))
1291 xhv->xhv_fill++; /* HvFILL(hv)++ */
1296 oentry = &HeNEXT(entry);
1298 if (!*aep) /* everything moved */
1299 xhv->xhv_fill--; /* HvFILL(hv)-- */
1304 Perl_newHVhv(pTHX_ HV *ohv)
1306 HV * const hv = newHV();
1307 STRLEN hv_max, hv_fill;
1309 if (!ohv || (hv_fill = HvFILL(ohv)) == 0)
1311 hv_max = HvMAX(ohv);
1313 if (!SvMAGICAL((SV *)ohv)) {
1314 /* It's an ordinary hash, so copy it fast. AMS 20010804 */
1316 const bool shared = !!HvSHAREKEYS(ohv);
1317 HE **ents, ** const oents = (HE **)HvARRAY(ohv);
1319 Newx(a, PERL_HV_ARRAY_ALLOC_BYTES(hv_max+1), char);
1322 /* In each bucket... */
1323 for (i = 0; i <= hv_max; i++) {
1325 HE *oent = oents[i];
1332 /* Copy the linked list of entries. */
1333 for (; oent; oent = HeNEXT(oent)) {
1334 const U32 hash = HeHASH(oent);
1335 const char * const key = HeKEY(oent);
1336 const STRLEN len = HeKLEN(oent);
1337 const int flags = HeKFLAGS(oent);
1338 HE * const ent = new_HE();
1340 HeVAL(ent) = newSVsv(HeVAL(oent));
1342 = shared ? share_hek_flags(key, len, hash, flags)
1343 : save_hek_flags(key, len, hash, flags);
1354 HvFILL(hv) = hv_fill;
1355 HvTOTALKEYS(hv) = HvTOTALKEYS(ohv);
1359 /* Iterate over ohv, copying keys and values one at a time. */
1361 const I32 riter = HvRITER_get(ohv);
1362 HE * const eiter = HvEITER_get(ohv);
1364 /* Can we use fewer buckets? (hv_max is always 2^n-1) */
1365 while (hv_max && hv_max + 1 >= hv_fill * 2)
1366 hv_max = hv_max / 2;
1370 while ((entry = hv_iternext_flags(ohv, 0))) {
1371 (void)hv_store_flags(hv, HeKEY(entry), HeKLEN(entry),
1372 newSVsv(HeVAL(entry)), HeHASH(entry),
1375 HvRITER_set(ohv, riter);
1376 HvEITER_set(ohv, eiter);
1382 /* A rather specialised version of newHVhv for copying %^H, ensuring all the
1383 magic stays on it. */
1385 Perl_hv_copy_hints_hv(pTHX_ HV *const ohv)
1387 HV * const hv = newHV();
1390 if (ohv && (hv_fill = HvFILL(ohv))) {
1391 STRLEN hv_max = HvMAX(ohv);
1393 const I32 riter = HvRITER_get(ohv);
1394 HE * const eiter = HvEITER_get(ohv);
1396 while (hv_max && hv_max + 1 >= hv_fill * 2)
1397 hv_max = hv_max / 2;
1401 while ((entry = hv_iternext_flags(ohv, 0))) {
1402 SV *const sv = newSVsv(HeVAL(entry));
1403 sv_magic(sv, NULL, PERL_MAGIC_hintselem,
1404 (char *)newSVhek (HeKEY_hek(entry)), HEf_SVKEY);
1405 (void)hv_store_flags(hv, HeKEY(entry), HeKLEN(entry),
1406 sv, HeHASH(entry), HeKFLAGS(entry));
1408 HvRITER_set(ohv, riter);
1409 HvEITER_set(ohv, eiter);
1411 hv_magic(hv, NULL, PERL_MAGIC_hints);
1416 Perl_hv_free_ent(pTHX_ HV *hv, register HE *entry)
1424 if (val && isGV(val) && isGV_with_GP(val) && GvCVu(val) && HvNAME_get(hv))
1425 mro_method_changed_in(hv); /* deletion of method from stash */
1427 if (HeKLEN(entry) == HEf_SVKEY) {
1428 SvREFCNT_dec(HeKEY_sv(entry));
1429 Safefree(HeKEY_hek(entry));
1431 else if (HvSHAREKEYS(hv))
1432 unshare_hek(HeKEY_hek(entry));
1434 Safefree(HeKEY_hek(entry));
1439 Perl_hv_delayfree_ent(pTHX_ HV *hv, register HE *entry)
1444 /* SvREFCNT_inc to counter the SvREFCNT_dec in hv_free_ent */
1445 sv_2mortal(SvREFCNT_inc(HeVAL(entry))); /* free between statements */
1446 if (HeKLEN(entry) == HEf_SVKEY) {
1447 sv_2mortal(SvREFCNT_inc(HeKEY_sv(entry)));
1449 hv_free_ent(hv, entry);
1453 =for apidoc hv_clear
1455 Clears a hash, making it empty.
1461 Perl_hv_clear(pTHX_ HV *hv)
1464 register XPVHV* xhv;
1468 DEBUG_A(Perl_hv_assert(aTHX_ hv));
1470 xhv = (XPVHV*)SvANY(hv);
1472 if (SvREADONLY(hv) && HvARRAY(hv) != NULL) {
1473 /* restricted hash: convert all keys to placeholders */
1475 for (i = 0; i <= xhv->xhv_max; i++) {
1476 HE *entry = (HvARRAY(hv))[i];
1477 for (; entry; entry = HeNEXT(entry)) {
1478 /* not already placeholder */
1479 if (HeVAL(entry) != &PL_sv_placeholder) {
1480 if (HeVAL(entry) && SvREADONLY(HeVAL(entry))) {
1481 SV* const keysv = hv_iterkeysv(entry);
1483 "Attempt to delete readonly key '%"SVf"' from a restricted hash",
1486 SvREFCNT_dec(HeVAL(entry));
1487 HeVAL(entry) = &PL_sv_placeholder;
1488 HvPLACEHOLDERS(hv)++;
1496 HvPLACEHOLDERS_set(hv, 0);
1498 Zero(HvARRAY(hv), xhv->xhv_max+1 /* HvMAX(hv)+1 */, HE*);
1503 HvHASKFLAGS_off(hv);
1508 mro_isa_changed_in(hv);
1509 HvEITER_set(hv, NULL);
1514 =for apidoc hv_clear_placeholders
1516 Clears any placeholders from a hash. If a restricted hash has any of its keys
1517 marked as readonly and the key is subsequently deleted, the key is not actually
1518 deleted but is marked by assigning it a value of &PL_sv_placeholder. This tags
1519 it so it will be ignored by future operations such as iterating over the hash,
1520 but will still allow the hash to have a value reassigned to the key at some
1521 future point. This function clears any such placeholder keys from the hash.
1522 See Hash::Util::lock_keys() for an example of its use.
1528 Perl_hv_clear_placeholders(pTHX_ HV *hv)
1531 const U32 items = (U32)HvPLACEHOLDERS_get(hv);
1534 clear_placeholders(hv, items);
1538 S_clear_placeholders(pTHX_ HV *hv, U32 items)
1548 /* Loop down the linked list heads */
1550 HE **oentry = &(HvARRAY(hv))[i];
1553 while ((entry = *oentry)) {
1554 if (HeVAL(entry) == &PL_sv_placeholder) {
1555 *oentry = HeNEXT(entry);
1556 if (first && !*oentry)
1557 HvFILL(hv)--; /* This linked list is now empty. */
1558 if (entry == HvEITER_get(hv))
1561 hv_free_ent(hv, entry);
1565 HvTOTALKEYS(hv) -= (IV)HvPLACEHOLDERS_get(hv);
1566 if (HvKEYS(hv) == 0)
1567 HvHASKFLAGS_off(hv);
1568 HvPLACEHOLDERS_set(hv, 0);
1572 oentry = &HeNEXT(entry);
1577 /* You can't get here, hence assertion should always fail. */
1578 assert (items == 0);
1583 S_hfreeentries(pTHX_ HV *hv)
1585 /* This is the array that we're going to restore */
1586 HE **const orig_array = HvARRAY(hv);
1594 /* If the hash is actually a symbol table with a name, look after the
1596 struct xpvhv_aux *iter = HvAUX(hv);
1598 name = iter->xhv_name;
1599 iter->xhv_name = NULL;
1604 /* orig_array remains unchanged throughout the loop. If after freeing all
1605 the entries it turns out that one of the little blighters has triggered
1606 an action that has caused HvARRAY to be re-allocated, then we set
1607 array to the new HvARRAY, and try again. */
1610 /* This is the one we're going to try to empty. First time round
1611 it's the original array. (Hopefully there will only be 1 time
1613 HE ** const array = HvARRAY(hv);
1616 /* Because we have taken xhv_name out, the only allocated pointer
1617 in the aux structure that might exist is the backreference array.
1622 struct mro_meta *meta;
1623 struct xpvhv_aux *iter = HvAUX(hv);
1624 /* If there are weak references to this HV, we need to avoid
1625 freeing them up here. In particular we need to keep the AV
1626 visible as what we're deleting might well have weak references
1627 back to this HV, so the for loop below may well trigger
1628 the removal of backreferences from this array. */
1630 if (iter->xhv_backreferences) {
1631 /* So donate them to regular backref magic to keep them safe.
1632 The sv_magic will increase the reference count of the AV,
1633 so we need to drop it first. */
1634 SvREFCNT_dec(iter->xhv_backreferences);
1635 if (AvFILLp(iter->xhv_backreferences) == -1) {
1636 /* Turns out that the array is empty. Just free it. */
1637 SvREFCNT_dec(iter->xhv_backreferences);
1640 sv_magic((SV*)hv, (SV*)iter->xhv_backreferences,
1641 PERL_MAGIC_backref, NULL, 0);
1643 iter->xhv_backreferences = NULL;
1646 entry = iter->xhv_eiter; /* HvEITER(hv) */
1647 if (entry && HvLAZYDEL(hv)) { /* was deleted earlier? */
1649 hv_free_ent(hv, entry);
1651 iter->xhv_riter = -1; /* HvRITER(hv) = -1 */
1652 iter->xhv_eiter = NULL; /* HvEITER(hv) = NULL */
1654 if((meta = iter->xhv_mro_meta)) {
1655 if(meta->mro_linear_dfs) SvREFCNT_dec(meta->mro_linear_dfs);
1656 if(meta->mro_linear_c3) SvREFCNT_dec(meta->mro_linear_c3);
1657 if(meta->mro_nextmethod) SvREFCNT_dec(meta->mro_nextmethod);
1659 iter->xhv_mro_meta = NULL;
1662 /* There are now no allocated pointers in the aux structure. */
1664 SvFLAGS(hv) &= ~SVf_OOK; /* Goodbye, aux structure. */
1665 /* What aux structure? */
1668 /* make everyone else think the array is empty, so that the destructors
1669 * called for freed entries can't recusively mess with us */
1672 ((XPVHV*) SvANY(hv))->xhv_keys = 0;
1676 /* Loop down the linked list heads */
1677 HE *entry = array[i];
1680 register HE * const oentry = entry;
1681 entry = HeNEXT(entry);
1682 hv_free_ent(hv, oentry);
1686 /* As there are no allocated pointers in the aux structure, it's now
1687 safe to free the array we just cleaned up, if it's not the one we're
1688 going to put back. */
1689 if (array != orig_array) {
1694 /* Good. No-one added anything this time round. */
1699 /* Someone attempted to iterate or set the hash name while we had
1700 the array set to 0. We'll catch backferences on the next time
1701 round the while loop. */
1702 assert(HvARRAY(hv));
1704 if (HvAUX(hv)->xhv_name) {
1705 unshare_hek_or_pvn(HvAUX(hv)->xhv_name, 0, 0, 0);
1709 if (--attempts == 0) {
1710 Perl_die(aTHX_ "panic: hfreeentries failed to free hash - something is repeatedly re-creating entries");
1714 HvARRAY(hv) = orig_array;
1716 /* If the hash was actually a symbol table, put the name back. */
1718 /* We have restored the original array. If name is non-NULL, then
1719 the original array had an aux structure at the end. So this is
1721 SvFLAGS(hv) |= SVf_OOK;
1722 HvAUX(hv)->xhv_name = name;
1727 =for apidoc hv_undef
1735 Perl_hv_undef(pTHX_ HV *hv)
1738 register XPVHV* xhv;
1743 DEBUG_A(Perl_hv_assert(aTHX_ hv));
1744 xhv = (XPVHV*)SvANY(hv);
1746 if ((name = HvNAME_get(hv)) && !PL_dirty)
1747 mro_isa_changed_in(hv);
1752 (void)hv_delete(PL_stashcache, name, HvNAMELEN_get(hv), G_DISCARD);
1753 hv_name_set(hv, NULL, 0, 0);
1755 SvFLAGS(hv) &= ~SVf_OOK;
1756 Safefree(HvARRAY(hv));
1757 xhv->xhv_max = 7; /* HvMAX(hv) = 7 (it's a normal hash) */
1759 HvPLACEHOLDERS_set(hv, 0);
1765 static struct xpvhv_aux*
1766 S_hv_auxinit(HV *hv) {
1767 struct xpvhv_aux *iter;
1771 Newxz(array, PERL_HV_ARRAY_ALLOC_BYTES(HvMAX(hv) + 1)
1772 + sizeof(struct xpvhv_aux), char);
1774 array = (char *) HvARRAY(hv);
1775 Renew(array, PERL_HV_ARRAY_ALLOC_BYTES(HvMAX(hv) + 1)
1776 + sizeof(struct xpvhv_aux), char);
1778 HvARRAY(hv) = (HE**) array;
1779 /* SvOOK_on(hv) attacks the IV flags. */
1780 SvFLAGS(hv) |= SVf_OOK;
1783 iter->xhv_riter = -1; /* HvRITER(hv) = -1 */
1784 iter->xhv_eiter = NULL; /* HvEITER(hv) = NULL */
1786 iter->xhv_backreferences = 0;
1787 iter->xhv_mro_meta = NULL;
1792 =for apidoc hv_iterinit
1794 Prepares a starting point to traverse a hash table. Returns the number of
1795 keys in the hash (i.e. the same as C<HvKEYS(tb)>). The return value is
1796 currently only meaningful for hashes without tie magic.
1798 NOTE: Before version 5.004_65, C<hv_iterinit> used to return the number of
1799 hash buckets that happen to be in use. If you still need that esoteric
1800 value, you can get it through the macro C<HvFILL(tb)>.
1807 Perl_hv_iterinit(pTHX_ HV *hv)
1810 Perl_croak(aTHX_ "Bad hash");
1813 struct xpvhv_aux * const iter = HvAUX(hv);
1814 HE * const entry = iter->xhv_eiter; /* HvEITER(hv) */
1815 if (entry && HvLAZYDEL(hv)) { /* was deleted earlier? */
1817 hv_free_ent(hv, entry);
1819 iter->xhv_riter = -1; /* HvRITER(hv) = -1 */
1820 iter->xhv_eiter = NULL; /* HvEITER(hv) = NULL */
1825 /* used to be xhv->xhv_fill before 5.004_65 */
1826 return HvTOTALKEYS(hv);
1830 Perl_hv_riter_p(pTHX_ HV *hv) {
1831 struct xpvhv_aux *iter;
1834 Perl_croak(aTHX_ "Bad hash");
1836 iter = SvOOK(hv) ? HvAUX(hv) : hv_auxinit(hv);
1837 return &(iter->xhv_riter);
1841 Perl_hv_eiter_p(pTHX_ HV *hv) {
1842 struct xpvhv_aux *iter;
1845 Perl_croak(aTHX_ "Bad hash");
1847 iter = SvOOK(hv) ? HvAUX(hv) : hv_auxinit(hv);
1848 return &(iter->xhv_eiter);
1852 Perl_hv_riter_set(pTHX_ HV *hv, I32 riter) {
1853 struct xpvhv_aux *iter;
1856 Perl_croak(aTHX_ "Bad hash");
1864 iter = hv_auxinit(hv);
1866 iter->xhv_riter = riter;
1870 Perl_hv_eiter_set(pTHX_ HV *hv, HE *eiter) {
1871 struct xpvhv_aux *iter;
1874 Perl_croak(aTHX_ "Bad hash");
1879 /* 0 is the default so don't go malloc()ing a new structure just to
1884 iter = hv_auxinit(hv);
1886 iter->xhv_eiter = eiter;
1890 Perl_hv_name_set(pTHX_ HV *hv, const char *name, U32 len, U32 flags)
1893 struct xpvhv_aux *iter;
1896 PERL_UNUSED_ARG(flags);
1899 Perl_croak(aTHX_ "panic: hv name too long (%"UVuf")", (UV) len);
1903 if (iter->xhv_name) {
1904 unshare_hek_or_pvn(iter->xhv_name, 0, 0, 0);
1910 iter = hv_auxinit(hv);
1912 PERL_HASH(hash, name, len);
1913 iter->xhv_name = name ? share_hek(name, len, hash) : NULL;
1917 Perl_hv_backreferences_p(pTHX_ HV *hv) {
1918 struct xpvhv_aux * const iter = SvOOK(hv) ? HvAUX(hv) : hv_auxinit(hv);
1919 PERL_UNUSED_CONTEXT;
1920 return &(iter->xhv_backreferences);
1924 Perl_hv_kill_backrefs(pTHX_ HV *hv) {
1930 av = HvAUX(hv)->xhv_backreferences;
1933 HvAUX(hv)->xhv_backreferences = 0;
1934 Perl_sv_kill_backrefs(aTHX_ (SV*) hv, av);
1939 hv_iternext is implemented as a macro in hv.h
1941 =for apidoc hv_iternext
1943 Returns entries from a hash iterator. See C<hv_iterinit>.
1945 You may call C<hv_delete> or C<hv_delete_ent> on the hash entry that the
1946 iterator currently points to, without losing your place or invalidating your
1947 iterator. Note that in this case the current entry is deleted from the hash
1948 with your iterator holding the last reference to it. Your iterator is flagged
1949 to free the entry on the next call to C<hv_iternext>, so you must not discard
1950 your iterator immediately else the entry will leak - call C<hv_iternext> to
1951 trigger the resource deallocation.
1953 =for apidoc hv_iternext_flags
1955 Returns entries from a hash iterator. See C<hv_iterinit> and C<hv_iternext>.
1956 The C<flags> value will normally be zero; if HV_ITERNEXT_WANTPLACEHOLDERS is
1957 set the placeholders keys (for restricted hashes) will be returned in addition
1958 to normal keys. By default placeholders are automatically skipped over.
1959 Currently a placeholder is implemented with a value that is
1960 C<&Perl_sv_placeholder>. Note that the implementation of placeholders and
1961 restricted hashes may change, and the implementation currently is
1962 insufficiently abstracted for any change to be tidy.
1968 Perl_hv_iternext_flags(pTHX_ HV *hv, I32 flags)
1971 register XPVHV* xhv;
1975 struct xpvhv_aux *iter;
1978 Perl_croak(aTHX_ "Bad hash");
1980 xhv = (XPVHV*)SvANY(hv);
1983 /* Too many things (well, pp_each at least) merrily assume that you can
1984 call iv_iternext without calling hv_iterinit, so we'll have to deal
1990 oldentry = entry = iter->xhv_eiter; /* HvEITER(hv) */
1991 if (SvMAGICAL(hv) && SvRMAGICAL(hv)) {
1992 if ( ( mg = mg_find((SV*)hv, PERL_MAGIC_tied) ) ) {
1993 SV * const key = sv_newmortal();
1995 sv_setsv(key, HeSVKEY_force(entry));
1996 SvREFCNT_dec(HeSVKEY(entry)); /* get rid of previous key */
2002 /* one HE per MAGICAL hash */
2003 iter->xhv_eiter = entry = new_HE(); /* HvEITER(hv) = new_HE() */
2005 Newxz(k, HEK_BASESIZE + sizeof(SV*), char);
2007 HeKEY_hek(entry) = hek;
2008 HeKLEN(entry) = HEf_SVKEY;
2010 magic_nextpack((SV*) hv,mg,key);
2012 /* force key to stay around until next time */
2013 HeSVKEY_set(entry, SvREFCNT_inc_simple_NN(key));
2014 return entry; /* beware, hent_val is not set */
2017 SvREFCNT_dec(HeVAL(entry));
2018 Safefree(HeKEY_hek(entry));
2020 iter->xhv_eiter = NULL; /* HvEITER(hv) = NULL */
2024 #if defined(DYNAMIC_ENV_FETCH) && !defined(__riscos__) /* set up %ENV for iteration */
2025 if (!entry && SvRMAGICAL((SV*)hv) && mg_find((SV*)hv, PERL_MAGIC_env)) {
2028 /* The prime_env_iter() on VMS just loaded up new hash values
2029 * so the iteration count needs to be reset back to the beginning
2033 oldentry = entry = iter->xhv_eiter; /* HvEITER(hv) */
2038 /* hv_iterint now ensures this. */
2039 assert (HvARRAY(hv));
2041 /* At start of hash, entry is NULL. */
2044 entry = HeNEXT(entry);
2045 if (!(flags & HV_ITERNEXT_WANTPLACEHOLDERS)) {
2047 * Skip past any placeholders -- don't want to include them in
2050 while (entry && HeVAL(entry) == &PL_sv_placeholder) {
2051 entry = HeNEXT(entry);
2056 /* OK. Come to the end of the current list. Grab the next one. */
2058 iter->xhv_riter++; /* HvRITER(hv)++ */
2059 if (iter->xhv_riter > (I32)xhv->xhv_max /* HvRITER(hv) > HvMAX(hv) */) {
2060 /* There is no next one. End of the hash. */
2061 iter->xhv_riter = -1; /* HvRITER(hv) = -1 */
2064 entry = (HvARRAY(hv))[iter->xhv_riter];
2066 if (!(flags & HV_ITERNEXT_WANTPLACEHOLDERS)) {
2067 /* If we have an entry, but it's a placeholder, don't count it.
2069 while (entry && HeVAL(entry) == &PL_sv_placeholder)
2070 entry = HeNEXT(entry);
2072 /* Will loop again if this linked list starts NULL
2073 (for HV_ITERNEXT_WANTPLACEHOLDERS)
2074 or if we run through it and find only placeholders. */
2077 if (oldentry && HvLAZYDEL(hv)) { /* was deleted earlier? */
2079 hv_free_ent(hv, oldentry);
2082 /*if (HvREHASH(hv) && entry && !HeKREHASH(entry))
2083 PerlIO_printf(PerlIO_stderr(), "Awooga %p %p\n", (void*)hv, (void*)entry);*/
2085 iter->xhv_eiter = entry; /* HvEITER(hv) = entry */
2090 =for apidoc hv_iterkey
2092 Returns the key from the current position of the hash iterator. See
2099 Perl_hv_iterkey(pTHX_ register HE *entry, I32 *retlen)
2101 if (HeKLEN(entry) == HEf_SVKEY) {
2103 char * const p = SvPV(HeKEY_sv(entry), len);
2108 *retlen = HeKLEN(entry);
2109 return HeKEY(entry);
2113 /* unlike hv_iterval(), this always returns a mortal copy of the key */
2115 =for apidoc hv_iterkeysv
2117 Returns the key as an C<SV*> from the current position of the hash
2118 iterator. The return value will always be a mortal copy of the key. Also
2125 Perl_hv_iterkeysv(pTHX_ register HE *entry)
2127 return sv_2mortal(newSVhek(HeKEY_hek(entry)));
2131 =for apidoc hv_iterval
2133 Returns the value from the current position of the hash iterator. See
2140 Perl_hv_iterval(pTHX_ HV *hv, register HE *entry)
2142 if (SvRMAGICAL(hv)) {
2143 if (mg_find((SV*)hv, PERL_MAGIC_tied)) {
2144 SV* const sv = sv_newmortal();
2145 if (HeKLEN(entry) == HEf_SVKEY)
2146 mg_copy((SV*)hv, sv, (char*)HeKEY_sv(entry), HEf_SVKEY);
2148 mg_copy((SV*)hv, sv, HeKEY(entry), HeKLEN(entry));
2152 return HeVAL(entry);
2156 =for apidoc hv_iternextsv
2158 Performs an C<hv_iternext>, C<hv_iterkey>, and C<hv_iterval> in one
2165 Perl_hv_iternextsv(pTHX_ HV *hv, char **key, I32 *retlen)
2167 HE * const he = hv_iternext_flags(hv, 0);
2171 *key = hv_iterkey(he, retlen);
2172 return hv_iterval(hv, he);
2179 =for apidoc hv_magic
2181 Adds magic to a hash. See C<sv_magic>.
2186 /* possibly free a shared string if no one has access to it
2187 * len and hash must both be valid for str.
2190 Perl_unsharepvn(pTHX_ const char *str, I32 len, U32 hash)
2192 unshare_hek_or_pvn (NULL, str, len, hash);
2197 Perl_unshare_hek(pTHX_ HEK *hek)
2200 unshare_hek_or_pvn(hek, NULL, 0, 0);
2203 /* possibly free a shared string if no one has access to it
2204 hek if non-NULL takes priority over the other 3, else str, len and hash
2205 are used. If so, len and hash must both be valid for str.
2208 S_unshare_hek_or_pvn(pTHX_ const HEK *hek, const char *str, I32 len, U32 hash)
2211 register XPVHV* xhv;
2213 register HE **oentry;
2215 bool is_utf8 = FALSE;
2217 const char * const save = str;
2218 struct shared_he *he = NULL;
2221 /* Find the shared he which is just before us in memory. */
2222 he = (struct shared_he *)(((char *)hek)
2223 - STRUCT_OFFSET(struct shared_he,
2226 /* Assert that the caller passed us a genuine (or at least consistent)
2228 assert (he->shared_he_he.hent_hek == hek);
2231 if (he->shared_he_he.he_valu.hent_refcount - 1) {
2232 --he->shared_he_he.he_valu.hent_refcount;
2233 UNLOCK_STRTAB_MUTEX;
2236 UNLOCK_STRTAB_MUTEX;
2238 hash = HEK_HASH(hek);
2239 } else if (len < 0) {
2240 STRLEN tmplen = -len;
2242 /* See the note in hv_fetch(). --jhi */
2243 str = (char*)bytes_from_utf8((U8*)str, &tmplen, &is_utf8);
2246 k_flags = HVhek_UTF8;
2248 k_flags |= HVhek_WASUTF8 | HVhek_FREEKEY;
2251 /* what follows was the moral equivalent of:
2252 if ((Svp = hv_fetch(PL_strtab, tmpsv, FALSE, hash))) {
2254 hv_delete(PL_strtab, str, len, G_DISCARD, hash);
2256 xhv = (XPVHV*)SvANY(PL_strtab);
2257 /* assert(xhv_array != 0) */
2259 first = oentry = &(HvARRAY(PL_strtab))[hash & (I32) HvMAX(PL_strtab)];
2261 const HE *const he_he = &(he->shared_he_he);
2262 for (entry = *oentry; entry; oentry = &HeNEXT(entry), entry = *oentry) {
2267 const int flags_masked = k_flags & HVhek_MASK;
2268 for (entry = *oentry; entry; oentry = &HeNEXT(entry), entry = *oentry) {
2269 if (HeHASH(entry) != hash) /* strings can't be equal */
2271 if (HeKLEN(entry) != len)
2273 if (HeKEY(entry) != str && memNE(HeKEY(entry),str,len)) /* is this it? */
2275 if (HeKFLAGS(entry) != flags_masked)
2282 if (--entry->he_valu.hent_refcount == 0) {
2283 *oentry = HeNEXT(entry);
2285 /* There are now no entries in our slot. */
2286 xhv->xhv_fill--; /* HvFILL(hv)-- */
2289 xhv->xhv_keys--; /* HvTOTALKEYS(hv)-- */
2293 UNLOCK_STRTAB_MUTEX;
2294 if (!entry && ckWARN_d(WARN_INTERNAL))
2295 Perl_warner(aTHX_ packWARN(WARN_INTERNAL),
2296 "Attempt to free non-existent shared string '%s'%s"
2298 hek ? HEK_KEY(hek) : str,
2299 ((k_flags & HVhek_UTF8) ? " (utf8)" : "") pTHX__VALUE);
2300 if (k_flags & HVhek_FREEKEY)
2304 /* get a (constant) string ptr from the global string table
2305 * string will get added if it is not already there.
2306 * len and hash must both be valid for str.
2309 Perl_share_hek(pTHX_ const char *str, I32 len, register U32 hash)
2311 bool is_utf8 = FALSE;
2313 const char * const save = str;
2316 STRLEN tmplen = -len;
2318 /* See the note in hv_fetch(). --jhi */
2319 str = (char*)bytes_from_utf8((U8*)str, &tmplen, &is_utf8);
2321 /* If we were able to downgrade here, then than means that we were passed
2322 in a key which only had chars 0-255, but was utf8 encoded. */
2325 /* If we found we were able to downgrade the string to bytes, then
2326 we should flag that it needs upgrading on keys or each. Also flag
2327 that we need share_hek_flags to free the string. */
2329 flags |= HVhek_WASUTF8 | HVhek_FREEKEY;
2332 return share_hek_flags (str, len, hash, flags);
2336 S_share_hek_flags(pTHX_ const char *str, I32 len, register U32 hash, int flags)
2340 const int flags_masked = flags & HVhek_MASK;
2341 const U32 hindex = hash & (I32) HvMAX(PL_strtab);
2343 /* what follows is the moral equivalent of:
2345 if (!(Svp = hv_fetch(PL_strtab, str, len, FALSE)))
2346 hv_store(PL_strtab, str, len, NULL, hash);
2348 Can't rehash the shared string table, so not sure if it's worth
2349 counting the number of entries in the linked list
2351 register XPVHV * const xhv = (XPVHV*)SvANY(PL_strtab);
2352 /* assert(xhv_array != 0) */
2354 entry = (HvARRAY(PL_strtab))[hindex];
2355 for (;entry; entry = HeNEXT(entry)) {
2356 if (HeHASH(entry) != hash) /* strings can't be equal */
2358 if (HeKLEN(entry) != len)
2360 if (HeKEY(entry) != str && memNE(HeKEY(entry),str,len)) /* is this it? */
2362 if (HeKFLAGS(entry) != flags_masked)
2368 /* What used to be head of the list.
2369 If this is NULL, then we're the first entry for this slot, which
2370 means we need to increate fill. */
2371 struct shared_he *new_entry;
2374 HE **const head = &HvARRAY(PL_strtab)[hindex];
2375 HE *const next = *head;
2377 /* We don't actually store a HE from the arena and a regular HEK.
2378 Instead we allocate one chunk of memory big enough for both,
2379 and put the HEK straight after the HE. This way we can find the
2380 HEK directly from the HE.
2383 Newx(k, STRUCT_OFFSET(struct shared_he,
2384 shared_he_hek.hek_key[0]) + len + 2, char);
2385 new_entry = (struct shared_he *)k;
2386 entry = &(new_entry->shared_he_he);
2387 hek = &(new_entry->shared_he_hek);
2389 Copy(str, HEK_KEY(hek), len, char);
2390 HEK_KEY(hek)[len] = 0;
2392 HEK_HASH(hek) = hash;
2393 HEK_FLAGS(hek) = (unsigned char)flags_masked;
2395 /* Still "point" to the HEK, so that other code need not know what
2397 HeKEY_hek(entry) = hek;
2398 entry->he_valu.hent_refcount = 0;
2399 HeNEXT(entry) = next;
2402 xhv->xhv_keys++; /* HvTOTALKEYS(hv)++ */
2403 if (!next) { /* initial entry? */
2404 xhv->xhv_fill++; /* HvFILL(hv)++ */
2405 } else if (xhv->xhv_keys > (IV)xhv->xhv_max /* HvKEYS(hv) > HvMAX(hv) */) {
2410 ++entry->he_valu.hent_refcount;
2411 UNLOCK_STRTAB_MUTEX;
2413 if (flags & HVhek_FREEKEY)
2416 return HeKEY_hek(entry);
2420 Perl_hv_placeholders_p(pTHX_ HV *hv)
2423 MAGIC *mg = mg_find((SV*)hv, PERL_MAGIC_rhash);
2426 mg = sv_magicext((SV*)hv, 0, PERL_MAGIC_rhash, 0, 0, 0);
2429 Perl_die(aTHX_ "panic: hv_placeholders_p");
2432 return &(mg->mg_len);
2437 Perl_hv_placeholders_get(pTHX_ HV *hv)
2440 MAGIC * const mg = mg_find((SV*)hv, PERL_MAGIC_rhash);
2442 return mg ? mg->mg_len : 0;
2446 Perl_hv_placeholders_set(pTHX_ HV *hv, I32 ph)
2449 MAGIC * const mg = mg_find((SV*)hv, PERL_MAGIC_rhash);
2454 if (!sv_magicext((SV*)hv, 0, PERL_MAGIC_rhash, 0, 0, ph))
2455 Perl_die(aTHX_ "panic: hv_placeholders_set");
2457 /* else we don't need to add magic to record 0 placeholders. */
2461 S_refcounted_he_value(pTHX_ const struct refcounted_he *he)
2465 switch(he->refcounted_he_data[0] & HVrhek_typemask) {
2470 value = &PL_sv_placeholder;
2473 value = newSViv(he->refcounted_he_val.refcounted_he_u_iv);
2476 value = newSVuv(he->refcounted_he_val.refcounted_he_u_uv);
2479 case HVrhek_PV_UTF8:
2480 /* Create a string SV that directly points to the bytes in our
2482 value = newSV_type(SVt_PV);
2483 SvPV_set(value, (char *) he->refcounted_he_data + 1);
2484 SvCUR_set(value, he->refcounted_he_val.refcounted_he_u_len);
2485 /* This stops anything trying to free it */
2486 SvLEN_set(value, 0);
2488 SvREADONLY_on(value);
2489 if ((he->refcounted_he_data[0] & HVrhek_typemask) == HVrhek_PV_UTF8)
2493 Perl_croak(aTHX_ "panic: refcounted_he_value bad flags %x",
2494 he->refcounted_he_data[0]);
2500 =for apidoc refcounted_he_chain_2hv
2502 Generates and returns a C<HV *> by walking up the tree starting at the passed
2503 in C<struct refcounted_he *>.
2508 Perl_refcounted_he_chain_2hv(pTHX_ const struct refcounted_he *chain)
2512 U32 placeholders = 0;
2513 /* We could chase the chain once to get an idea of the number of keys,
2514 and call ksplit. But for now we'll make a potentially inefficient
2515 hash with only 8 entries in its array. */
2516 const U32 max = HvMAX(hv);
2520 Newxz(array, PERL_HV_ARRAY_ALLOC_BYTES(max + 1), char);
2521 HvARRAY(hv) = (HE**)array;
2526 U32 hash = chain->refcounted_he_hash;
2528 U32 hash = HEK_HASH(chain->refcounted_he_hek);
2530 HE **oentry = &((HvARRAY(hv))[hash & max]);
2531 HE *entry = *oentry;
2534 for (; entry; entry = HeNEXT(entry)) {
2535 if (HeHASH(entry) == hash) {
2536 /* We might have a duplicate key here. If so, entry is older
2537 than the key we've already put in the hash, so if they are
2538 the same, skip adding entry. */
2540 const STRLEN klen = HeKLEN(entry);
2541 const char *const key = HeKEY(entry);
2542 if (klen == chain->refcounted_he_keylen
2543 && (!!HeKUTF8(entry)
2544 == !!(chain->refcounted_he_data[0] & HVhek_UTF8))
2545 && memEQ(key, REF_HE_KEY(chain), klen))
2548 if (HeKEY_hek(entry) == chain->refcounted_he_hek)
2550 if (HeKLEN(entry) == HEK_LEN(chain->refcounted_he_hek)
2551 && HeKUTF8(entry) == HEK_UTF8(chain->refcounted_he_hek)
2552 && memEQ(HeKEY(entry), HEK_KEY(chain->refcounted_he_hek),
2563 = share_hek_flags(REF_HE_KEY(chain),
2564 chain->refcounted_he_keylen,
2565 chain->refcounted_he_hash,
2566 (chain->refcounted_he_data[0]
2567 & (HVhek_UTF8|HVhek_WASUTF8)));
2569 HeKEY_hek(entry) = share_hek_hek(chain->refcounted_he_hek);
2571 value = refcounted_he_value(chain);
2572 if (value == &PL_sv_placeholder)
2574 HeVAL(entry) = value;
2576 /* Link it into the chain. */
2577 HeNEXT(entry) = *oentry;
2578 if (!HeNEXT(entry)) {
2579 /* initial entry. */
2587 chain = chain->refcounted_he_next;
2591 clear_placeholders(hv, placeholders);
2592 HvTOTALKEYS(hv) -= placeholders;
2595 /* We could check in the loop to see if we encounter any keys with key
2596 flags, but it's probably not worth it, as this per-hash flag is only
2597 really meant as an optimisation for things like Storable. */
2599 DEBUG_A(Perl_hv_assert(aTHX_ hv));
2605 Perl_refcounted_he_fetch(pTHX_ const struct refcounted_he *chain, SV *keysv,
2606 const char *key, STRLEN klen, int flags, U32 hash)
2609 /* Just to be awkward, if you're using this interface the UTF-8-or-not-ness
2610 of your key has to exactly match that which is stored. */
2611 SV *value = &PL_sv_placeholder;
2615 if (flags & HVhek_FREEKEY)
2617 key = SvPV_const(keysv, klen);
2619 is_utf8 = (SvUTF8(keysv) != 0);
2621 is_utf8 = ((flags & HVhek_UTF8) ? TRUE : FALSE);
2625 if (keysv && (SvIsCOW_shared_hash(keysv))) {
2626 hash = SvSHARED_HASH(keysv);
2628 PERL_HASH(hash, key, klen);
2632 for (; chain; chain = chain->refcounted_he_next) {
2634 if (hash != chain->refcounted_he_hash)
2636 if (klen != chain->refcounted_he_keylen)
2638 if (memNE(REF_HE_KEY(chain),key,klen))
2640 if (!!is_utf8 != !!(chain->refcounted_he_data[0] & HVhek_UTF8))
2643 if (hash != HEK_HASH(chain->refcounted_he_hek))
2645 if (klen != (STRLEN)HEK_LEN(chain->refcounted_he_hek))
2647 if (memNE(HEK_KEY(chain->refcounted_he_hek),key,klen))
2649 if (!!is_utf8 != !!HEK_UTF8(chain->refcounted_he_hek))
2653 value = sv_2mortal(refcounted_he_value(chain));
2657 if (flags & HVhek_FREEKEY)
2664 =for apidoc refcounted_he_new
2666 Creates a new C<struct refcounted_he>. As S<key> is copied, and value is
2667 stored in a compact form, all references remain the property of the caller.
2668 The C<struct refcounted_he> is returned with a reference count of 1.
2673 struct refcounted_he *
2674 Perl_refcounted_he_new(pTHX_ struct refcounted_he *const parent,
2675 SV *const key, SV *const value) {
2677 struct refcounted_he *he;
2679 const char *key_p = SvPV_const(key, key_len);
2680 STRLEN value_len = 0;
2681 const char *value_p = NULL;
2686 bool is_utf8 = SvUTF8(key) ? TRUE : FALSE;
2689 value_type = HVrhek_PV;
2690 } else if (SvIOK(value)) {
2691 value_type = HVrhek_IV;
2692 } else if (value == &PL_sv_placeholder) {
2693 value_type = HVrhek_delete;
2694 } else if (!SvOK(value)) {
2695 value_type = HVrhek_undef;
2697 value_type = HVrhek_PV;
2700 if (value_type == HVrhek_PV) {
2701 value_p = SvPV_const(value, value_len);
2702 key_offset = value_len + 2;
2709 he = (struct refcounted_he*)
2710 PerlMemShared_malloc(sizeof(struct refcounted_he) - 1
2714 he = (struct refcounted_he*)
2715 PerlMemShared_malloc(sizeof(struct refcounted_he) - 1
2720 he->refcounted_he_next = parent;
2722 if (value_type == HVrhek_PV) {
2723 Copy(value_p, he->refcounted_he_data + 1, value_len + 1, char);
2724 he->refcounted_he_val.refcounted_he_u_len = value_len;
2725 /* Do it this way so that the SvUTF8() test is after the SvPV, in case
2726 the value is overloaded, and doesn't yet have the UTF-8flag set. */
2728 value_type = HVrhek_PV_UTF8;
2729 } else if (value_type == HVrhek_IV) {
2731 he->refcounted_he_val.refcounted_he_u_uv = SvUVX(value);
2732 value_type = HVrhek_UV;
2734 he->refcounted_he_val.refcounted_he_u_iv = SvIVX(value);
2740 /* Hash keys are always stored normalised to (yes) ISO-8859-1.
2741 As we're going to be building hash keys from this value in future,
2742 normalise it now. */
2743 key_p = (char*)bytes_from_utf8((const U8*)key_p, &key_len, &is_utf8);
2744 flags |= is_utf8 ? HVhek_UTF8 : HVhek_WASUTF8;
2746 PERL_HASH(hash, key_p, key_len);
2749 he->refcounted_he_hash = hash;
2750 he->refcounted_he_keylen = key_len;
2751 Copy(key_p, he->refcounted_he_data + key_offset, key_len, char);
2753 he->refcounted_he_hek = share_hek_flags(key_p, key_len, hash, flags);
2756 if (flags & HVhek_WASUTF8) {
2757 /* If it was downgraded from UTF-8, then the pointer returned from
2758 bytes_from_utf8 is an allocated pointer that we must free. */
2762 he->refcounted_he_data[0] = flags;
2763 he->refcounted_he_refcnt = 1;
2769 =for apidoc refcounted_he_free
2771 Decrements the reference count of the passed in C<struct refcounted_he *>
2772 by one. If the reference count reaches zero the structure's memory is freed,
2773 and C<refcounted_he_free> iterates onto the parent node.
2779 Perl_refcounted_he_free(pTHX_ struct refcounted_he *he) {
2781 PERL_UNUSED_CONTEXT;
2784 struct refcounted_he *copy;
2788 new_count = --he->refcounted_he_refcnt;
2789 HINTS_REFCNT_UNLOCK;
2795 #ifndef USE_ITHREADS
2796 unshare_hek_or_pvn (he->refcounted_he_hek, 0, 0, 0);
2799 he = he->refcounted_he_next;
2800 PerlMemShared_free(copy);
2805 =for apidoc hv_assert
2807 Check that a hash is in an internally consistent state.
2815 Perl_hv_assert(pTHX_ HV *hv)
2820 int placeholders = 0;
2823 const I32 riter = HvRITER_get(hv);
2824 HE *eiter = HvEITER_get(hv);
2826 (void)hv_iterinit(hv);
2828 while ((entry = hv_iternext_flags(hv, HV_ITERNEXT_WANTPLACEHOLDERS))) {
2829 /* sanity check the values */
2830 if (HeVAL(entry) == &PL_sv_placeholder)
2834 /* sanity check the keys */
2835 if (HeSVKEY(entry)) {
2836 NOOP; /* Don't know what to check on SV keys. */
2837 } else if (HeKUTF8(entry)) {
2839 if (HeKWASUTF8(entry)) {
2840 PerlIO_printf(Perl_debug_log,
2841 "hash key has both WASUTF8 and UTF8: '%.*s'\n",
2842 (int) HeKLEN(entry), HeKEY(entry));
2845 } else if (HeKWASUTF8(entry))
2848 if (!SvTIED_mg((SV*)hv, PERL_MAGIC_tied)) {
2849 static const char bad_count[] = "Count %d %s(s), but hash reports %d\n";
2850 const int nhashkeys = HvUSEDKEYS(hv);
2851 const int nhashplaceholders = HvPLACEHOLDERS_get(hv);
2853 if (nhashkeys != real) {
2854 PerlIO_printf(Perl_debug_log, bad_count, real, "keys", nhashkeys );
2857 if (nhashplaceholders != placeholders) {
2858 PerlIO_printf(Perl_debug_log, bad_count, placeholders, "placeholder", nhashplaceholders );
2862 if (withflags && ! HvHASKFLAGS(hv)) {
2863 PerlIO_printf(Perl_debug_log,
2864 "Hash has HASKFLAGS off but I count %d key(s) with flags\n",
2871 HvRITER_set(hv, riter); /* Restore hash iterator state */
2872 HvEITER_set(hv, eiter);
2879 * c-indentation-style: bsd
2881 * indent-tabs-mode: t
2884 * ex: set ts=8 sts=4 sw=4 noet: