3 * Copyright (C) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
4 * 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008 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
13 * of all that I have seen.
16 * [p.278 of _The Lord of the Rings_, II/iii: "The Ring Goes South"]
20 =head1 Hash Manipulation Functions
21 A HV structure represents a Perl hash. It consists mainly of an array
22 of pointers, each of which points to a linked list of HE structures. The
23 array is indexed by the hash function of the key, so each linked list
24 represents all the hash entries with the same hash value. Each HE contains
25 a pointer to the actual value, plus a pointer to a HEK structure which
26 holds the key and hash value.
34 #define PERL_HASH_INTERNAL_ACCESS
37 #define DO_HSPLIT(xhv) ((xhv)->xhv_keys > (xhv)->xhv_max) /* HvTOTALKEYS(hv) > HvMAX(hv) */
38 #define HV_FILL_THRESHOLD 31
40 static const char S_strtab_error[]
41 = "Cannot modify shared string table in hv_%s";
45 #define new_HE() (HE*)safemalloc(sizeof(HE))
46 #define del_HE(p) safefree((char*)p)
54 void ** const root = &PL_body_roots[HE_SVSLOT];
57 Perl_more_bodies(aTHX_ HE_SVSLOT, sizeof(HE), PERL_ARENA_SIZE);
64 #define new_HE() new_he()
67 HeNEXT(p) = (HE*)(PL_body_roots[HE_SVSLOT]); \
68 PL_body_roots[HE_SVSLOT] = p; \
76 S_save_hek_flags(const char *str, I32 len, U32 hash, int flags)
78 const int flags_masked = flags & HVhek_MASK;
82 PERL_ARGS_ASSERT_SAVE_HEK_FLAGS;
84 Newx(k, HEK_BASESIZE + len + 2, char);
86 Copy(str, HEK_KEY(hek), len, char);
87 HEK_KEY(hek)[len] = 0;
90 HEK_FLAGS(hek) = (unsigned char)flags_masked | HVhek_UNSHARED;
92 if (flags & HVhek_FREEKEY)
97 /* free the pool of temporary HE/HEK pairs returned by hv_fetch_ent
101 Perl_free_tied_hv_pool(pTHX)
103 HE *he = PL_hv_fetch_ent_mh;
106 Safefree(HeKEY_hek(he));
110 PL_hv_fetch_ent_mh = NULL;
113 #if defined(USE_ITHREADS)
115 Perl_hek_dup(pTHX_ HEK *source, CLONE_PARAMS* param)
119 PERL_ARGS_ASSERT_HEK_DUP;
120 PERL_UNUSED_ARG(param);
125 shared = (HEK*)ptr_table_fetch(PL_ptr_table, source);
127 /* We already shared this hash key. */
128 (void)share_hek_hek(shared);
132 = share_hek_flags(HEK_KEY(source), HEK_LEN(source),
133 HEK_HASH(source), HEK_FLAGS(source));
134 ptr_table_store(PL_ptr_table, source, shared);
140 Perl_he_dup(pTHX_ const HE *e, bool shared, CLONE_PARAMS* param)
144 PERL_ARGS_ASSERT_HE_DUP;
148 /* look for it in the table first */
149 ret = (HE*)ptr_table_fetch(PL_ptr_table, e);
153 /* create anew and remember what it is */
155 ptr_table_store(PL_ptr_table, e, ret);
157 HeNEXT(ret) = he_dup(HeNEXT(e),shared, param);
158 if (HeKLEN(e) == HEf_SVKEY) {
160 Newx(k, HEK_BASESIZE + sizeof(const SV *), char);
161 HeKEY_hek(ret) = (HEK*)k;
162 HeKEY_sv(ret) = sv_dup_inc(HeKEY_sv(e), param);
165 /* This is hek_dup inlined, which seems to be important for speed
167 HEK * const source = HeKEY_hek(e);
168 HEK *shared = (HEK*)ptr_table_fetch(PL_ptr_table, source);
171 /* We already shared this hash key. */
172 (void)share_hek_hek(shared);
176 = share_hek_flags(HEK_KEY(source), HEK_LEN(source),
177 HEK_HASH(source), HEK_FLAGS(source));
178 ptr_table_store(PL_ptr_table, source, shared);
180 HeKEY_hek(ret) = shared;
183 HeKEY_hek(ret) = save_hek_flags(HeKEY(e), HeKLEN(e), HeHASH(e),
185 HeVAL(ret) = sv_dup_inc(HeVAL(e), param);
188 #endif /* USE_ITHREADS */
191 S_hv_notallowed(pTHX_ int flags, const char *key, I32 klen,
194 SV * const sv = sv_newmortal();
196 PERL_ARGS_ASSERT_HV_NOTALLOWED;
198 if (!(flags & HVhek_FREEKEY)) {
199 sv_setpvn(sv, key, klen);
202 /* Need to free saved eventually assign to mortal SV */
203 /* XXX is this line an error ???: SV *sv = sv_newmortal(); */
204 sv_usepvn(sv, (char *) key, klen);
206 if (flags & HVhek_UTF8) {
209 Perl_croak(aTHX_ msg, SVfARG(sv));
212 /* (klen == HEf_SVKEY) is special for MAGICAL hv entries, meaning key slot
218 Stores an SV in a hash. The hash key is specified as C<key> and the
219 absolute value of C<klen> is the length of the key. If C<klen> is
220 negative the key is assumed to be in UTF-8-encoded Unicode. The
221 C<hash> parameter is the precomputed hash value; if it is zero then
222 Perl will compute it.
224 The return value will be
225 C<NULL> if the operation failed or if the value did not need to be actually
226 stored within the hash (as in the case of tied hashes). Otherwise it can
227 be dereferenced to get the original C<SV*>. Note that the caller is
228 responsible for suitably incrementing the reference count of C<val> before
229 the call, and decrementing it if the function returned C<NULL>. Effectively
230 a successful C<hv_store> takes ownership of one reference to C<val>. This is
231 usually what you want; a newly created SV has a reference count of one, so
232 if all your code does is create SVs then store them in a hash, C<hv_store>
233 will own the only reference to the new SV, and your code doesn't need to do
234 anything further to tidy up. C<hv_store> is not implemented as a call to
235 C<hv_store_ent>, and does not create a temporary SV for the key, so if your
236 key data is not already in SV form then use C<hv_store> in preference to
239 See L<perlguts/"Understanding the Magic of Tied Hashes and Arrays"> for more
240 information on how to use this function on tied hashes.
242 =for apidoc hv_store_ent
244 Stores C<val> in a hash. The hash key is specified as C<key>. The C<hash>
245 parameter is the precomputed hash value; if it is zero then Perl will
246 compute it. The return value is the new hash entry so created. It will be
247 C<NULL> if the operation failed or if the value did not need to be actually
248 stored within the hash (as in the case of tied hashes). Otherwise the
249 contents of the return value can be accessed using the C<He?> macros
250 described here. Note that the caller is responsible for suitably
251 incrementing the reference count of C<val> before the call, and
252 decrementing it if the function returned NULL. Effectively a successful
253 C<hv_store_ent> takes ownership of one reference to C<val>. This is
254 usually what you want; a newly created SV has a reference count of one, so
255 if all your code does is create SVs then store them in a hash, C<hv_store>
256 will own the only reference to the new SV, and your code doesn't need to do
257 anything further to tidy up. Note that C<hv_store_ent> only reads the C<key>;
258 unlike C<val> it does not take ownership of it, so maintaining the correct
259 reference count on C<key> is entirely the caller's responsibility. C<hv_store>
260 is not implemented as a call to C<hv_store_ent>, and does not create a temporary
261 SV for the key, so if your key data is not already in SV form then use
262 C<hv_store> in preference to C<hv_store_ent>.
264 See L<perlguts/"Understanding the Magic of Tied Hashes and Arrays"> for more
265 information on how to use this function on tied hashes.
267 =for apidoc hv_exists
269 Returns a boolean indicating whether the specified hash key exists. The
270 absolute value of C<klen> is the length of the key. If C<klen> is
271 negative the key is assumed to be in UTF-8-encoded Unicode.
275 Returns the SV which corresponds to the specified key in the hash.
276 The absolute value of C<klen> is the length of the key. If C<klen> is
277 negative the key is assumed to be in UTF-8-encoded Unicode. If
278 C<lval> is set then the fetch will be part of a store. This means that if
279 there is no value in the hash associated with the given key, then one is
280 created and a pointer to it is returned. The C<SV*> it points to can be
281 assigned to. But always check that the
282 return value is non-null before dereferencing it to an C<SV*>.
284 See L<perlguts/"Understanding the Magic of Tied Hashes and Arrays"> for more
285 information on how to use this function on tied hashes.
287 =for apidoc hv_exists_ent
289 Returns a boolean indicating whether
290 the specified hash key exists. C<hash>
291 can be a valid precomputed hash value, or 0 to ask for it to be
297 /* returns an HE * structure with the all fields set */
298 /* note that hent_val will be a mortal sv for MAGICAL hashes */
300 =for apidoc hv_fetch_ent
302 Returns the hash entry which corresponds to the specified key in the hash.
303 C<hash> must be a valid precomputed hash number for the given C<key>, or 0
304 if you want the function to compute it. IF C<lval> is set then the fetch
305 will be part of a store. Make sure the return value is non-null before
306 accessing it. The return value when C<hv> is a tied hash is a pointer to a
307 static location, so be sure to make a copy of the structure if you need to
310 See L<perlguts/"Understanding the Magic of Tied Hashes and Arrays"> for more
311 information on how to use this function on tied hashes.
316 /* Common code for hv_delete()/hv_exists()/hv_fetch()/hv_store() */
318 Perl_hv_common_key_len(pTHX_ HV *hv, const char *key, I32 klen_i32,
319 const int action, SV *val, const U32 hash)
324 PERL_ARGS_ASSERT_HV_COMMON_KEY_LEN;
333 return hv_common(hv, NULL, key, klen, flags, action, val, hash);
337 Perl_hv_common(pTHX_ HV *hv, SV *keysv, const char *key, STRLEN klen,
338 int flags, int action, SV *val, U32 hash)
347 const int return_svp = action & HV_FETCH_JUST_SV;
348 HEK *keysv_hek = NULL;
352 if (SvTYPE(hv) == (svtype)SVTYPEMASK)
355 assert(SvTYPE(hv) == SVt_PVHV);
357 if (SvSMAGICAL(hv) && SvGMAGICAL(hv) && !(action & HV_DISABLE_UVAR_XKEY)) {
359 if ((mg = mg_find((const SV *)hv, PERL_MAGIC_uvar))) {
360 struct ufuncs * const uf = (struct ufuncs *)mg->mg_ptr;
361 if (uf->uf_set == NULL) {
362 SV* obj = mg->mg_obj;
365 keysv = newSVpvn_flags(key, klen, SVs_TEMP |
366 ((flags & HVhek_UTF8)
370 mg->mg_obj = keysv; /* pass key */
371 uf->uf_index = action; /* pass action */
372 magic_getuvar(MUTABLE_SV(hv), mg);
373 keysv = mg->mg_obj; /* may have changed */
376 /* If the key may have changed, then we need to invalidate
377 any passed-in computed hash value. */
383 if (flags & HVhek_FREEKEY)
385 key = SvPV_const(keysv, klen);
386 is_utf8 = (SvUTF8(keysv) != 0);
387 if (SvIsCOW_shared_hash(keysv)) {
388 flags = HVhek_KEYCANONICAL | (is_utf8 ? HVhek_UTF8 : 0);
390 flags = is_utf8 ? HVhek_UTF8 : 0;
393 is_utf8 = ((flags & HVhek_UTF8) ? TRUE : FALSE);
396 if (action & HV_DELETE) {
397 return (void *) hv_delete_common(hv, keysv, key, klen,
398 flags, action, hash);
401 xhv = (XPVHV*)SvANY(hv);
403 if (SvRMAGICAL(hv) && !(action & (HV_FETCH_ISSTORE|HV_FETCH_ISEXISTS))) {
404 if (mg_find((const SV *)hv, PERL_MAGIC_tied)
405 || SvGMAGICAL((const SV *)hv))
407 /* FIXME should be able to skimp on the HE/HEK here when
408 HV_FETCH_JUST_SV is true. */
410 keysv = newSVpvn_utf8(key, klen, is_utf8);
412 keysv = newSVsv(keysv);
415 mg_copy(MUTABLE_SV(hv), sv, (char *)keysv, HEf_SVKEY);
417 /* grab a fake HE/HEK pair from the pool or make a new one */
418 entry = PL_hv_fetch_ent_mh;
420 PL_hv_fetch_ent_mh = HeNEXT(entry);
424 Newx(k, HEK_BASESIZE + sizeof(const SV *), char);
425 HeKEY_hek(entry) = (HEK*)k;
427 HeNEXT(entry) = NULL;
428 HeSVKEY_set(entry, keysv);
430 sv_upgrade(sv, SVt_PVLV);
432 /* so we can free entry when freeing sv */
433 LvTARG(sv) = MUTABLE_SV(entry);
435 /* XXX remove at some point? */
436 if (flags & HVhek_FREEKEY)
440 return entry ? (void *) &HeVAL(entry) : NULL;
442 return (void *) entry;
444 #ifdef ENV_IS_CASELESS
445 else if (mg_find((const SV *)hv, PERL_MAGIC_env)) {
447 for (i = 0; i < klen; ++i)
448 if (isLOWER(key[i])) {
449 /* Would be nice if we had a routine to do the
450 copy and upercase in a single pass through. */
451 const char * const nkey = strupr(savepvn(key,klen));
452 /* Note that this fetch is for nkey (the uppercased
453 key) whereas the store is for key (the original) */
454 void *result = hv_common(hv, NULL, nkey, klen,
455 HVhek_FREEKEY, /* free nkey */
456 0 /* non-LVAL fetch */
457 | HV_DISABLE_UVAR_XKEY
460 0 /* compute hash */);
461 if (!result && (action & HV_FETCH_LVALUE)) {
462 /* This call will free key if necessary.
463 Do it this way to encourage compiler to tail
465 result = hv_common(hv, keysv, key, klen, flags,
467 | HV_DISABLE_UVAR_XKEY
471 if (flags & HVhek_FREEKEY)
479 else if (SvRMAGICAL(hv) && (action & HV_FETCH_ISEXISTS)) {
480 if (mg_find((const SV *)hv, PERL_MAGIC_tied)
481 || SvGMAGICAL((const SV *)hv)) {
482 /* I don't understand why hv_exists_ent has svret and sv,
483 whereas hv_exists only had one. */
484 SV * const svret = sv_newmortal();
487 if (keysv || is_utf8) {
489 keysv = newSVpvn_utf8(key, klen, TRUE);
491 keysv = newSVsv(keysv);
493 mg_copy(MUTABLE_SV(hv), sv, (char *)sv_2mortal(keysv), HEf_SVKEY);
495 mg_copy(MUTABLE_SV(hv), sv, key, klen);
497 if (flags & HVhek_FREEKEY)
500 MAGIC * const mg = mg_find(sv, PERL_MAGIC_tiedelem);
502 magic_existspack(svret, mg);
504 /* This cast somewhat evil, but I'm merely using NULL/
505 not NULL to return the boolean exists.
506 And I know hv is not NULL. */
507 return SvTRUE(svret) ? (void *)hv : NULL;
509 #ifdef ENV_IS_CASELESS
510 else if (mg_find((const SV *)hv, PERL_MAGIC_env)) {
511 /* XXX This code isn't UTF8 clean. */
512 char * const keysave = (char * const)key;
513 /* Will need to free this, so set FREEKEY flag. */
514 key = savepvn(key,klen);
515 key = (const char*)strupr((char*)key);
520 if (flags & HVhek_FREEKEY) {
523 flags |= HVhek_FREEKEY;
527 else if (action & HV_FETCH_ISSTORE) {
530 hv_magic_check (hv, &needs_copy, &needs_store);
532 const bool save_taint = TAINT_get;
533 if (keysv || is_utf8) {
535 keysv = newSVpvn_utf8(key, klen, TRUE);
538 TAINT_set(SvTAINTED(keysv));
539 keysv = sv_2mortal(newSVsv(keysv));
540 mg_copy(MUTABLE_SV(hv), val, (char*)keysv, HEf_SVKEY);
542 mg_copy(MUTABLE_SV(hv), val, key, klen);
545 TAINT_IF(save_taint);
546 #ifdef NO_TAINT_SUPPORT
547 PERL_UNUSED_VAR(save_taint);
550 if (flags & HVhek_FREEKEY)
554 #ifdef ENV_IS_CASELESS
555 else if (mg_find((const SV *)hv, PERL_MAGIC_env)) {
556 /* XXX This code isn't UTF8 clean. */
557 const char *keysave = key;
558 /* Will need to free this, so set FREEKEY flag. */
559 key = savepvn(key,klen);
560 key = (const char*)strupr((char*)key);
565 if (flags & HVhek_FREEKEY) {
568 flags |= HVhek_FREEKEY;
576 if ((action & (HV_FETCH_LVALUE | HV_FETCH_ISSTORE))
577 #ifdef DYNAMIC_ENV_FETCH /* if it's an %ENV lookup, we may get it on the fly */
578 || (SvRMAGICAL((const SV *)hv)
579 && mg_find((const SV *)hv, PERL_MAGIC_env))
584 PERL_HV_ARRAY_ALLOC_BYTES(xhv->xhv_max+1 /* HvMAX(hv)+1 */),
586 HvARRAY(hv) = (HE**)array;
588 #ifdef DYNAMIC_ENV_FETCH
589 else if (action & HV_FETCH_ISEXISTS) {
590 /* for an %ENV exists, if we do an insert it's by a recursive
591 store call, so avoid creating HvARRAY(hv) right now. */
595 /* XXX remove at some point? */
596 if (flags & HVhek_FREEKEY)
603 if (is_utf8 && !(flags & HVhek_KEYCANONICAL)) {
604 char * const keysave = (char *)key;
605 key = (char*)bytes_from_utf8((U8*)key, &klen, &is_utf8);
609 flags &= ~HVhek_UTF8;
610 if (key != keysave) {
611 if (flags & HVhek_FREEKEY)
613 flags |= HVhek_WASUTF8 | HVhek_FREEKEY;
614 /* If the caller calculated a hash, it was on the sequence of
615 octets that are the UTF-8 form. We've now changed the sequence
616 of octets stored to that of the equivalent byte representation,
617 so the hash we need is different. */
622 if (keysv && (SvIsCOW_shared_hash(keysv))) {
624 keysv_hek = SvSHARED_HEK_FROM_PV(SvPVX_const(keysv));
625 hash = SvSHARED_HASH(keysv);
628 PERL_HASH(hash, key, klen);
630 masked_flags = (flags & HVhek_MASK);
632 #ifdef DYNAMIC_ENV_FETCH
633 if (!HvARRAY(hv)) entry = NULL;
637 entry = (HvARRAY(hv))[hash & (I32) HvMAX(hv)];
644 /* keysv is actually a HEK in disguise, so we can match just by
645 * comparing the HEK pointers in the HE chain. There is a slight
646 * caveat: on something like "\x80", which has both plain and utf8
647 * representations, perl's hashes do encoding-insensitive lookups,
648 * but preserve the encoding of the stored key. Thus a particular
649 * key could map to two different HEKs in PL_strtab. We only
650 * conclude 'not found' if all the flags are the same; otherwise
651 * we fall back to a full search (this should only happen in rare
654 int keysv_flags = HEK_FLAGS(keysv_hek);
655 HE *orig_entry = entry;
657 for (; entry; entry = HeNEXT(entry)) {
658 HEK *hek = HeKEY_hek(entry);
659 if (hek == keysv_hek)
661 if (HEK_FLAGS(hek) != keysv_flags)
662 break; /* need to do full match */
666 /* failed on shortcut - do full search loop */
670 for (; entry; entry = HeNEXT(entry)) {
671 if (HeHASH(entry) != hash) /* strings can't be equal */
673 if (HeKLEN(entry) != (I32)klen)
675 if (memNE(HeKEY(entry),key,klen)) /* is this it? */
677 if ((HeKFLAGS(entry) ^ masked_flags) & HVhek_UTF8)
681 if (action & (HV_FETCH_LVALUE|HV_FETCH_ISSTORE)) {
682 if (HeKFLAGS(entry) != masked_flags) {
683 /* We match if HVhek_UTF8 bit in our flags and hash key's
684 match. But if entry was set previously with HVhek_WASUTF8
685 and key now doesn't (or vice versa) then we should change
686 the key's flag, as this is assignment. */
687 if (HvSHAREKEYS(hv)) {
688 /* Need to swap the key we have for a key with the flags we
689 need. As keys are shared we can't just write to the
690 flag, so we share the new one, unshare the old one. */
691 HEK * const new_hek = share_hek_flags(key, klen, hash,
693 unshare_hek (HeKEY_hek(entry));
694 HeKEY_hek(entry) = new_hek;
696 else if (hv == PL_strtab) {
697 /* PL_strtab is usually the only hash without HvSHAREKEYS,
698 so putting this test here is cheap */
699 if (flags & HVhek_FREEKEY)
701 Perl_croak(aTHX_ S_strtab_error,
702 action & HV_FETCH_LVALUE ? "fetch" : "store");
705 HeKFLAGS(entry) = masked_flags;
706 if (masked_flags & HVhek_ENABLEHVKFLAGS)
709 if (HeVAL(entry) == &PL_sv_placeholder) {
710 /* yes, can store into placeholder slot */
711 if (action & HV_FETCH_LVALUE) {
713 /* This preserves behaviour with the old hv_fetch
714 implementation which at this point would bail out
715 with a break; (at "if we find a placeholder, we
716 pretend we haven't found anything")
718 That break mean that if a placeholder were found, it
719 caused a call into hv_store, which in turn would
720 check magic, and if there is no magic end up pretty
721 much back at this point (in hv_store's code). */
724 /* LVAL fetch which actually needs a store. */
726 HvPLACEHOLDERS(hv)--;
729 if (val != &PL_sv_placeholder)
730 HvPLACEHOLDERS(hv)--;
733 } else if (action & HV_FETCH_ISSTORE) {
734 SvREFCNT_dec(HeVAL(entry));
737 } else if (HeVAL(entry) == &PL_sv_placeholder) {
738 /* if we find a placeholder, we pretend we haven't found
742 if (flags & HVhek_FREEKEY)
745 return (void *) &HeVAL(entry);
751 #ifdef DYNAMIC_ENV_FETCH /* %ENV lookup? If so, try to fetch the value now */
752 if (!(action & HV_FETCH_ISSTORE)
753 && SvRMAGICAL((const SV *)hv)
754 && mg_find((const SV *)hv, PERL_MAGIC_env)) {
756 const char * const env = PerlEnv_ENVgetenv_len(key,&len);
758 sv = newSVpvn(env,len);
760 return hv_common(hv, keysv, key, klen, flags,
761 HV_FETCH_ISSTORE|HV_DISABLE_UVAR_XKEY|return_svp,
767 if (!entry && SvREADONLY(hv) && !(action & HV_FETCH_ISEXISTS)) {
768 hv_notallowed(flags, key, klen,
769 "Attempt to access disallowed key '%"SVf"' in"
770 " a restricted hash");
772 if (!(action & (HV_FETCH_LVALUE|HV_FETCH_ISSTORE))) {
773 /* Not doing some form of store, so return failure. */
774 if (flags & HVhek_FREEKEY)
778 if (action & HV_FETCH_LVALUE) {
779 val = action & HV_FETCH_EMPTY_HE ? NULL : newSV(0);
781 /* At this point the old hv_fetch code would call to hv_store,
782 which in turn might do some tied magic. So we need to make that
783 magic check happen. */
784 /* gonna assign to this, so it better be there */
785 /* If a fetch-as-store fails on the fetch, then the action is to
786 recurse once into "hv_store". If we didn't do this, then that
787 recursive call would call the key conversion routine again.
788 However, as we replace the original key with the converted
789 key, this would result in a double conversion, which would show
790 up as a bug if the conversion routine is not idempotent.
791 Hence the use of HV_DISABLE_UVAR_XKEY. */
792 return hv_common(hv, keysv, key, klen, flags,
793 HV_FETCH_ISSTORE|HV_DISABLE_UVAR_XKEY|return_svp,
795 /* XXX Surely that could leak if the fetch-was-store fails?
796 Just like the hv_fetch. */
800 /* Welcome to hv_store... */
803 /* Not sure if we can get here. I think the only case of oentry being
804 NULL is for %ENV with dynamic env fetch. But that should disappear
805 with magic in the previous code. */
808 PERL_HV_ARRAY_ALLOC_BYTES(xhv->xhv_max+1 /* HvMAX(hv)+1 */),
810 HvARRAY(hv) = (HE**)array;
813 oentry = &(HvARRAY(hv))[hash & (I32) xhv->xhv_max];
816 /* share_hek_flags will do the free for us. This might be considered
819 HeKEY_hek(entry) = share_hek_flags(key, klen, hash, flags);
820 else if (hv == PL_strtab) {
821 /* PL_strtab is usually the only hash without HvSHAREKEYS, so putting
822 this test here is cheap */
823 if (flags & HVhek_FREEKEY)
825 Perl_croak(aTHX_ S_strtab_error,
826 action & HV_FETCH_LVALUE ? "fetch" : "store");
828 else /* gotta do the real thing */
829 HeKEY_hek(entry) = save_hek_flags(key, klen, hash, flags);
832 if (!*oentry && SvOOK(hv)) {
833 /* initial entry, and aux struct present. */
834 struct xpvhv_aux *const aux = HvAUX(hv);
835 if (aux->xhv_fill_lazy)
836 ++aux->xhv_fill_lazy;
839 #ifdef PERL_HASH_RANDOMIZE_KEYS
840 /* This logic semi-randomizes the insert order in a bucket.
841 * Either we insert into the top, or the slot below the top,
842 * making it harder to see if there is a collision. We also
843 * reset the iterator randomizer if there is one.
845 if ( *oentry && PL_HASH_RAND_BITS_ENABLED) {
847 PL_hash_rand_bits= ROTL_UV(PL_hash_rand_bits,1);
848 if ( PL_hash_rand_bits & 1 ) {
849 HeNEXT(entry) = HeNEXT(*oentry);
850 HeNEXT(*oentry) = entry;
852 HeNEXT(entry) = *oentry;
858 HeNEXT(entry) = *oentry;
861 #ifdef PERL_HASH_RANDOMIZE_KEYS
863 /* Currently this makes various tests warn in annoying ways.
864 * So Silenced for now. - Yves | bogus end of comment =>* /
865 if (HvAUX(hv)->xhv_riter != -1) {
866 Perl_ck_warner_d(aTHX_ packWARN(WARN_INTERNAL),
867 "[TESTING] Inserting into a hash during each() traversal results in undefined behavior"
872 if (PL_HASH_RAND_BITS_ENABLED) {
873 if (PL_HASH_RAND_BITS_ENABLED == 1)
874 PL_hash_rand_bits += (PTRV)entry + 1; /* we don't bother to use ptr_hash here */
875 PL_hash_rand_bits= ROTL_UV(PL_hash_rand_bits,1);
877 HvAUX(hv)->xhv_rand= (U32)PL_hash_rand_bits;
881 if (val == &PL_sv_placeholder)
882 HvPLACEHOLDERS(hv)++;
883 if (masked_flags & HVhek_ENABLEHVKFLAGS)
886 xhv->xhv_keys++; /* HvTOTALKEYS(hv)++ */
887 if ( DO_HSPLIT(xhv) ) {
888 const STRLEN oldsize = xhv->xhv_max + 1;
889 const U32 items = (U32)HvPLACEHOLDERS_get(hv);
891 if (items /* hash has placeholders */
892 && !SvREADONLY(hv) /* but is not a restricted hash */) {
893 /* If this hash previously was a "restricted hash" and had
894 placeholders, but the "restricted" flag has been turned off,
895 then the placeholders no longer serve any useful purpose.
896 However, they have the downsides of taking up RAM, and adding
897 extra steps when finding used values. It's safe to clear them
898 at this point, even though Storable rebuilds restricted hashes by
899 putting in all the placeholders (first) before turning on the
900 readonly flag, because Storable always pre-splits the hash.
901 If we're lucky, then we may clear sufficient placeholders to
902 avoid needing to split the hash at all. */
903 clear_placeholders(hv, items);
905 hsplit(hv, oldsize, oldsize * 2);
907 hsplit(hv, oldsize, oldsize * 2);
911 return entry ? (void *) &HeVAL(entry) : NULL;
913 return (void *) entry;
917 S_hv_magic_check(HV *hv, bool *needs_copy, bool *needs_store)
919 const MAGIC *mg = SvMAGIC(hv);
921 PERL_ARGS_ASSERT_HV_MAGIC_CHECK;
926 if (isUPPER(mg->mg_type)) {
928 if (mg->mg_type == PERL_MAGIC_tied) {
929 *needs_store = FALSE;
930 return; /* We've set all there is to set. */
933 mg = mg->mg_moremagic;
938 =for apidoc hv_scalar
940 Evaluates the hash in scalar context and returns the result. Handles magic
941 when the hash is tied.
947 Perl_hv_scalar(pTHX_ HV *hv)
951 PERL_ARGS_ASSERT_HV_SCALAR;
953 if (SvRMAGICAL(hv)) {
954 MAGIC * const mg = mg_find((const SV *)hv, PERL_MAGIC_tied);
956 return magic_scalarpack(hv, mg);
960 if (HvTOTALKEYS((const HV *)hv))
961 Perl_sv_setpvf(aTHX_ sv, "%ld/%ld",
962 (long)HvFILL(hv), (long)HvMAX(hv) + 1);
970 =for apidoc hv_delete
972 Deletes a key/value pair in the hash. The value's SV is removed from
973 the hash, made mortal, and returned to the caller. The absolute
974 value of C<klen> is the length of the key. If C<klen> is negative the
975 key is assumed to be in UTF-8-encoded Unicode. The C<flags> value
976 will normally be zero; if set to C<G_DISCARD> then C<NULL> will be returned.
977 C<NULL> will also be returned if the key is not found.
979 =for apidoc hv_delete_ent
981 Deletes a key/value pair in the hash. The value SV is removed from the hash,
982 made mortal, and returned to the caller. The C<flags> value will normally be
983 zero; if set to C<G_DISCARD> then C<NULL> will be returned. C<NULL> will also
984 be returned if the key is not found. C<hash> can be a valid precomputed hash
985 value, or 0 to ask for it to be computed.
991 S_hv_delete_common(pTHX_ HV *hv, SV *keysv, const char *key, STRLEN klen,
992 int k_flags, I32 d_flags, U32 hash)
999 bool is_utf8 = (k_flags & HVhek_UTF8) ? TRUE : FALSE;
1001 HEK *keysv_hek = NULL;
1002 U8 mro_changes = 0; /* 1 = isa; 2 = package moved */
1007 if (SvRMAGICAL(hv)) {
1010 hv_magic_check (hv, &needs_copy, &needs_store);
1014 entry = (HE *) hv_common(hv, keysv, key, klen,
1015 k_flags & ~HVhek_FREEKEY,
1016 HV_FETCH_LVALUE|HV_DISABLE_UVAR_XKEY,
1018 sv = entry ? HeVAL(entry) : NULL;
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 NULL; /* element cannot be deleted */
1031 #ifdef ENV_IS_CASELESS
1032 else if (mg_find((const SV *)hv, PERL_MAGIC_env)) {
1033 /* XXX This code isn't UTF8 clean. */
1034 keysv = newSVpvn_flags(key, klen, SVs_TEMP);
1035 if (k_flags & HVhek_FREEKEY) {
1038 key = strupr(SvPVX(keysv));
1047 xhv = (XPVHV*)SvANY(hv);
1051 if (is_utf8 && !(k_flags & HVhek_KEYCANONICAL)) {
1052 const char * const keysave = key;
1053 key = (char*)bytes_from_utf8((U8*)key, &klen, &is_utf8);
1056 k_flags |= HVhek_UTF8;
1058 k_flags &= ~HVhek_UTF8;
1059 if (key != keysave) {
1060 if (k_flags & HVhek_FREEKEY) {
1061 /* This shouldn't happen if our caller does what we expect,
1062 but strictly the API allows it. */
1065 k_flags |= HVhek_WASUTF8 | HVhek_FREEKEY;
1067 HvHASKFLAGS_on(MUTABLE_SV(hv));
1070 if (keysv && (SvIsCOW_shared_hash(keysv))) {
1071 if (HvSHAREKEYS(hv))
1072 keysv_hek = SvSHARED_HEK_FROM_PV(SvPVX_const(keysv));
1073 hash = SvSHARED_HASH(keysv);
1076 PERL_HASH(hash, key, klen);
1078 masked_flags = (k_flags & HVhek_MASK);
1080 first_entry = oentry = &(HvARRAY(hv))[hash & (I32) HvMAX(hv)];
1087 /* keysv is actually a HEK in disguise, so we can match just by
1088 * comparing the HEK pointers in the HE chain. There is a slight
1089 * caveat: on something like "\x80", which has both plain and utf8
1090 * representations, perl's hashes do encoding-insensitive lookups,
1091 * but preserve the encoding of the stored key. Thus a particular
1092 * key could map to two different HEKs in PL_strtab. We only
1093 * conclude 'not found' if all the flags are the same; otherwise
1094 * we fall back to a full search (this should only happen in rare
1097 int keysv_flags = HEK_FLAGS(keysv_hek);
1099 for (; entry; oentry = &HeNEXT(entry), entry = *oentry) {
1100 HEK *hek = HeKEY_hek(entry);
1101 if (hek == keysv_hek)
1103 if (HEK_FLAGS(hek) != keysv_flags)
1104 break; /* need to do full match */
1108 /* failed on shortcut - do full search loop */
1109 oentry = first_entry;
1113 for (; entry; oentry = &HeNEXT(entry), entry = *oentry) {
1114 if (HeHASH(entry) != hash) /* strings can't be equal */
1116 if (HeKLEN(entry) != (I32)klen)
1118 if (memNE(HeKEY(entry),key,klen)) /* is this it? */
1120 if ((HeKFLAGS(entry) ^ masked_flags) & HVhek_UTF8)
1124 if (hv == PL_strtab) {
1125 if (k_flags & HVhek_FREEKEY)
1127 Perl_croak(aTHX_ S_strtab_error, "delete");
1130 /* if placeholder is here, it's already been deleted.... */
1131 if (HeVAL(entry) == &PL_sv_placeholder) {
1132 if (k_flags & HVhek_FREEKEY)
1136 if (SvREADONLY(hv) && HeVAL(entry) && SvREADONLY(HeVAL(entry))) {
1137 hv_notallowed(k_flags, key, klen,
1138 "Attempt to delete readonly key '%"SVf"' from"
1139 " a restricted hash");
1141 if (k_flags & HVhek_FREEKEY)
1144 /* If this is a stash and the key ends with ::, then someone is
1145 * deleting a package.
1147 if (HeVAL(entry) && HvENAME_get(hv)) {
1148 gv = (GV *)HeVAL(entry);
1149 if (keysv) key = SvPV(keysv, klen);
1151 (klen > 1 && key[klen-2] == ':' && key[klen-1] == ':')
1153 (klen == 1 && key[0] == ':')
1155 && (klen != 6 || hv!=PL_defstash || memNE(key,"main::",6))
1156 && SvTYPE(gv) == SVt_PVGV && (stash = GvHV((GV *)gv))
1157 && HvENAME_get(stash)) {
1158 /* A previous version of this code checked that the
1159 * GV was still in the symbol table by fetching the
1160 * GV with its name. That is not necessary (and
1161 * sometimes incorrect), as HvENAME cannot be set
1162 * on hv if it is not in the symtab. */
1164 /* Hang on to it for a bit. */
1165 SvREFCNT_inc_simple_void_NN(
1166 sv_2mortal((SV *)gv)
1169 else if (klen == 3 && strnEQ(key, "ISA", 3))
1173 sv = d_flags & G_DISCARD ? HeVAL(entry) : sv_2mortal(HeVAL(entry));
1174 HeVAL(entry) = &PL_sv_placeholder;
1176 /* deletion of method from stash */
1177 if (isGV(sv) && isGV_with_GP(sv) && GvCVu(sv)
1179 mro_method_changed_in(hv);
1183 * If a restricted hash, rather than really deleting the entry, put
1184 * a placeholder there. This marks the key as being "approved", so
1185 * we can still access via not-really-existing key without raising
1189 /* We'll be saving this slot, so the number of allocated keys
1190 * doesn't go down, but the number placeholders goes up */
1191 HvPLACEHOLDERS(hv)++;
1193 *oentry = HeNEXT(entry);
1194 if(!*first_entry && SvOOK(hv)) {
1195 /* removed last entry, and aux struct present. */
1196 struct xpvhv_aux *const aux = HvAUX(hv);
1197 if (aux->xhv_fill_lazy)
1198 --aux->xhv_fill_lazy;
1200 if (SvOOK(hv) && entry == HvAUX(hv)->xhv_eiter /* HvEITER(hv) */)
1203 if (SvOOK(hv) && HvLAZYDEL(hv) &&
1204 entry == HeNEXT(HvAUX(hv)->xhv_eiter))
1205 HeNEXT(HvAUX(hv)->xhv_eiter) = HeNEXT(entry);
1206 hv_free_ent(hv, entry);
1208 xhv->xhv_keys--; /* HvTOTALKEYS(hv)-- */
1209 if (xhv->xhv_keys == 0)
1210 HvHASKFLAGS_off(hv);
1213 if (d_flags & G_DISCARD) {
1218 if (mro_changes == 1) mro_isa_changed_in(hv);
1219 else if (mro_changes == 2)
1220 mro_package_moved(NULL, stash, gv, 1);
1226 if (SvREADONLY(hv)) {
1227 hv_notallowed(k_flags, key, klen,
1228 "Attempt to delete disallowed key '%"SVf"' from"
1229 " a restricted hash");
1232 if (k_flags & HVhek_FREEKEY)
1239 S_hsplit(pTHX_ HV *hv, STRLEN const oldsize, STRLEN newsize)
1242 char *a = (char*) HvARRAY(hv);
1246 /* already have an HvAUX(hv) so we have to move it */
1248 /* no HvAUX() but array we are going to allocate is large enough
1249 * there is no point in saving the space for the iterator, and
1250 * speeds up later traversals. */
1251 ( ( hv != PL_strtab ) && ( newsize >= PERL_HV_ALLOC_AUX_SIZE ) )
1254 PERL_ARGS_ASSERT_HSPLIT;
1257 Renew(a, PERL_HV_ARRAY_ALLOC_BYTES(newsize)
1258 + (do_aux ? sizeof(struct xpvhv_aux) : 0), char);
1264 #ifdef PERL_HASH_RANDOMIZE_KEYS
1265 /* the idea of this is that we create a "random" value by hashing the address of
1266 * the array, we then use the low bit to decide if we insert at the top, or insert
1267 * second from top. After each such insert we rotate the hashed value. So we can
1268 * use the same hashed value over and over, and in normal build environments use
1269 * very few ops to do so. ROTL32() should produce a single machine operation. */
1270 if (PL_HASH_RAND_BITS_ENABLED) {
1271 if (PL_HASH_RAND_BITS_ENABLED == 1)
1272 PL_hash_rand_bits += ptr_hash((PTRV)a);
1273 PL_hash_rand_bits = ROTL_UV(PL_hash_rand_bits,1);
1276 HvARRAY(hv) = (HE**) a;
1277 HvMAX(hv) = newsize - 1;
1278 /* before we zero the newly added memory, we
1279 * need to deal with the aux struct that may be there
1280 * or have been allocated by us*/
1282 struct xpvhv_aux *const dest
1283 = (struct xpvhv_aux*) &a[newsize * sizeof(HE*)];
1285 /* alread have an aux, copy the old one in place. */
1286 Move(&a[oldsize * sizeof(HE*)], dest, 1, struct xpvhv_aux);
1287 /* we reset the iterator's xhv_rand as well, so they get a totally new ordering */
1288 #ifdef PERL_HASH_RANDOMIZE_KEYS
1289 dest->xhv_rand = (U32)PL_hash_rand_bits;
1291 /* For now, just reset the lazy fill counter.
1292 It would be possible to update the counter in the code below
1294 dest->xhv_fill_lazy = 0;
1296 /* no existing aux structure, but we allocated space for one
1297 * so initialize it properly. This unrolls hv_auxinit() a bit,
1298 * since we have to do the realloc anyway. */
1299 /* first we set the iterator's xhv_rand so it can be copied into lastrand below */
1300 #ifdef PERL_HASH_RANDOMIZE_KEYS
1301 dest->xhv_rand = (U32)PL_hash_rand_bits;
1303 /* this is the "non realloc" part of the hv_auxinit() */
1304 (void)hv_auxinit_internal(dest);
1305 /* Turn on the OOK flag */
1309 /* now we can safely clear the second half */
1310 Zero(&a[oldsize * sizeof(HE*)], (newsize-oldsize) * sizeof(HE*), char); /* zero 2nd half*/
1312 if (!HvTOTALKEYS(hv)) /* skip rest if no entries */
1318 HE **oentry = aep + i;
1321 if (!entry) /* non-existent */
1324 U32 j = (HeHASH(entry) & newsize);
1326 *oentry = HeNEXT(entry);
1327 #ifdef PERL_HASH_RANDOMIZE_KEYS
1328 /* if the target cell is empty or PL_HASH_RAND_BITS_ENABLED is false
1329 * insert to top, otherwise rotate the bucket rand 1 bit,
1330 * and use the new low bit to decide if we insert at top,
1331 * or next from top. IOW, we only rotate on a collision.*/
1332 if (aep[j] && PL_HASH_RAND_BITS_ENABLED) {
1333 PL_hash_rand_bits+= ROTL32(HeHASH(entry), 17);
1334 PL_hash_rand_bits= ROTL_UV(PL_hash_rand_bits,1);
1335 if (PL_hash_rand_bits & 1) {
1336 HeNEXT(entry)= HeNEXT(aep[j]);
1337 HeNEXT(aep[j])= entry;
1339 /* Note, this is structured in such a way as the optimizer
1340 * should eliminate the duplicated code here and below without
1341 * us needing to explicitly use a goto. */
1342 HeNEXT(entry) = aep[j];
1348 /* see comment above about duplicated code */
1349 HeNEXT(entry) = aep[j];
1354 oentry = &HeNEXT(entry);
1358 } while (i++ < oldsize);
1362 Perl_hv_ksplit(pTHX_ HV *hv, IV newmax)
1364 XPVHV* xhv = (XPVHV*)SvANY(hv);
1365 const I32 oldsize = (I32) xhv->xhv_max+1; /* HvMAX(hv)+1 (sick) */
1369 PERL_ARGS_ASSERT_HV_KSPLIT;
1371 newsize = (I32) newmax; /* possible truncation here */
1372 if (newsize != newmax || newmax <= oldsize)
1374 while ((newsize & (1 + ~newsize)) != newsize) {
1375 newsize &= ~(newsize & (1 + ~newsize)); /* get proper power of 2 */
1377 if (newsize < newmax)
1379 if (newsize < newmax)
1380 return; /* overflow detection */
1382 a = (char *) HvARRAY(hv);
1384 hsplit(hv, oldsize, newsize);
1386 Newxz(a, PERL_HV_ARRAY_ALLOC_BYTES(newsize), char);
1387 xhv->xhv_max = --newsize;
1388 HvARRAY(hv) = (HE **) a;
1392 /* IMO this should also handle cases where hv_max is smaller than hv_keys
1393 * as tied hashes could play silly buggers and mess us around. We will
1394 * do the right thing during hv_store() afterwards, but still - Yves */
1395 #define HV_SET_MAX_ADJUSTED_FOR_KEYS(hv,hv_max,hv_keys) STMT_START {\
1396 /* Can we use fewer buckets? (hv_max is always 2^n-1) */ \
1397 if (hv_max < PERL_HASH_DEFAULT_HvMAX) { \
1398 hv_max = PERL_HASH_DEFAULT_HvMAX; \
1400 while (hv_max > PERL_HASH_DEFAULT_HvMAX && hv_max + 1 >= hv_keys * 2) \
1401 hv_max = hv_max / 2; \
1403 HvMAX(hv) = hv_max; \
1408 Perl_newHVhv(pTHX_ HV *ohv)
1411 HV * const hv = newHV();
1414 if (!ohv || (!HvTOTALKEYS(ohv) && !SvMAGICAL((const SV *)ohv)))
1416 hv_max = HvMAX(ohv);
1418 if (!SvMAGICAL((const SV *)ohv)) {
1419 /* It's an ordinary hash, so copy it fast. AMS 20010804 */
1421 const bool shared = !!HvSHAREKEYS(ohv);
1422 HE **ents, ** const oents = (HE **)HvARRAY(ohv);
1424 Newx(a, PERL_HV_ARRAY_ALLOC_BYTES(hv_max+1), char);
1427 /* In each bucket... */
1428 for (i = 0; i <= hv_max; i++) {
1430 HE *oent = oents[i];
1437 /* Copy the linked list of entries. */
1438 for (; oent; oent = HeNEXT(oent)) {
1439 const U32 hash = HeHASH(oent);
1440 const char * const key = HeKEY(oent);
1441 const STRLEN len = HeKLEN(oent);
1442 const int flags = HeKFLAGS(oent);
1443 HE * const ent = new_HE();
1444 SV *const val = HeVAL(oent);
1446 HeVAL(ent) = SvIMMORTAL(val) ? val : newSVsv(val);
1448 = shared ? share_hek_flags(key, len, hash, flags)
1449 : save_hek_flags(key, len, hash, flags);
1460 HvTOTALKEYS(hv) = HvTOTALKEYS(ohv);
1464 /* Iterate over ohv, copying keys and values one at a time. */
1466 const I32 riter = HvRITER_get(ohv);
1467 HE * const eiter = HvEITER_get(ohv);
1468 STRLEN hv_keys = HvTOTALKEYS(ohv);
1470 HV_SET_MAX_ADJUSTED_FOR_KEYS(hv,hv_max,hv_keys);
1473 while ((entry = hv_iternext_flags(ohv, 0))) {
1474 SV *val = hv_iterval(ohv,entry);
1475 SV * const keysv = HeSVKEY(entry);
1476 val = SvIMMORTAL(val) ? val : newSVsv(val);
1478 (void)hv_store_ent(hv, keysv, val, 0);
1480 (void)hv_store_flags(hv, HeKEY(entry), HeKLEN(entry), val,
1481 HeHASH(entry), HeKFLAGS(entry));
1483 HvRITER_set(ohv, riter);
1484 HvEITER_set(ohv, eiter);
1491 =for apidoc Am|HV *|hv_copy_hints_hv|HV *ohv
1493 A specialised version of L</newHVhv> for copying C<%^H>. C<ohv> must be
1494 a pointer to a hash (which may have C<%^H> magic, but should be generally
1495 non-magical), or C<NULL> (interpreted as an empty hash). The content
1496 of C<ohv> is copied to a new hash, which has the C<%^H>-specific magic
1497 added to it. A pointer to the new hash is returned.
1503 Perl_hv_copy_hints_hv(pTHX_ HV *const ohv)
1505 HV * const hv = newHV();
1508 STRLEN hv_max = HvMAX(ohv);
1509 STRLEN hv_keys = HvTOTALKEYS(ohv);
1511 const I32 riter = HvRITER_get(ohv);
1512 HE * const eiter = HvEITER_get(ohv);
1517 HV_SET_MAX_ADJUSTED_FOR_KEYS(hv,hv_max,hv_keys);
1520 while ((entry = hv_iternext_flags(ohv, 0))) {
1521 SV *const sv = newSVsv(hv_iterval(ohv,entry));
1522 SV *heksv = HeSVKEY(entry);
1523 if (!heksv && sv) heksv = newSVhek(HeKEY_hek(entry));
1524 if (sv) sv_magic(sv, NULL, PERL_MAGIC_hintselem,
1525 (char *)heksv, HEf_SVKEY);
1526 if (heksv == HeSVKEY(entry))
1527 (void)hv_store_ent(hv, heksv, sv, 0);
1529 (void)hv_common(hv, heksv, HeKEY(entry), HeKLEN(entry),
1530 HeKFLAGS(entry), HV_FETCH_ISSTORE|HV_FETCH_JUST_SV, sv, HeHASH(entry));
1531 SvREFCNT_dec_NN(heksv);
1534 HvRITER_set(ohv, riter);
1535 HvEITER_set(ohv, eiter);
1537 SvREFCNT_inc_simple_void_NN(hv);
1540 hv_magic(hv, NULL, PERL_MAGIC_hints);
1543 #undef HV_SET_MAX_ADJUSTED_FOR_KEYS
1545 /* like hv_free_ent, but returns the SV rather than freeing it */
1547 S_hv_free_ent_ret(pTHX_ HV *hv, HE *entry)
1551 PERL_ARGS_ASSERT_HV_FREE_ENT_RET;
1554 if (HeKLEN(entry) == HEf_SVKEY) {
1555 SvREFCNT_dec(HeKEY_sv(entry));
1556 Safefree(HeKEY_hek(entry));
1558 else if (HvSHAREKEYS(hv))
1559 unshare_hek(HeKEY_hek(entry));
1561 Safefree(HeKEY_hek(entry));
1568 Perl_hv_free_ent(pTHX_ HV *hv, HE *entry)
1572 PERL_ARGS_ASSERT_HV_FREE_ENT;
1576 val = hv_free_ent_ret(hv, entry);
1582 Perl_hv_delayfree_ent(pTHX_ HV *hv, HE *entry)
1584 PERL_ARGS_ASSERT_HV_DELAYFREE_ENT;
1588 /* SvREFCNT_inc to counter the SvREFCNT_dec in hv_free_ent */
1589 sv_2mortal(SvREFCNT_inc(HeVAL(entry))); /* free between statements */
1590 if (HeKLEN(entry) == HEf_SVKEY) {
1591 sv_2mortal(SvREFCNT_inc(HeKEY_sv(entry)));
1593 hv_free_ent(hv, entry);
1597 =for apidoc hv_clear
1599 Frees the all the elements of a hash, leaving it empty.
1600 The XS equivalent of C<%hash = ()>. See also L</hv_undef>.
1602 If any destructors are triggered as a result, the hv itself may
1609 Perl_hv_clear(pTHX_ HV *hv)
1616 DEBUG_A(Perl_hv_assert(aTHX_ hv));
1618 xhv = (XPVHV*)SvANY(hv);
1621 SAVEFREESV(SvREFCNT_inc_simple_NN(hv));
1622 if (SvREADONLY(hv) && HvARRAY(hv) != NULL) {
1623 /* restricted hash: convert all keys to placeholders */
1625 for (i = 0; i <= xhv->xhv_max; i++) {
1626 HE *entry = (HvARRAY(hv))[i];
1627 for (; entry; entry = HeNEXT(entry)) {
1628 /* not already placeholder */
1629 if (HeVAL(entry) != &PL_sv_placeholder) {
1631 if (SvREADONLY(HeVAL(entry))) {
1632 SV* const keysv = hv_iterkeysv(entry);
1633 Perl_croak_nocontext(
1634 "Attempt to delete readonly key '%"SVf"' from a restricted hash",
1637 SvREFCNT_dec_NN(HeVAL(entry));
1639 HeVAL(entry) = &PL_sv_placeholder;
1640 HvPLACEHOLDERS(hv)++;
1647 HvPLACEHOLDERS_set(hv, 0);
1650 mg_clear(MUTABLE_SV(hv));
1652 HvHASKFLAGS_off(hv);
1656 mro_isa_changed_in(hv);
1657 HvEITER_set(hv, NULL);
1663 =for apidoc hv_clear_placeholders
1665 Clears any placeholders from a hash. If a restricted hash has any of its keys
1666 marked as readonly and the key is subsequently deleted, the key is not actually
1667 deleted but is marked by assigning it a value of C<&PL_sv_placeholder>. This tags
1668 it so it will be ignored by future operations such as iterating over the hash,
1669 but will still allow the hash to have a value reassigned to the key at some
1670 future point. This function clears any such placeholder keys from the hash.
1671 See C<L<Hash::Util::lock_keys()|Hash::Util/lock_keys>> for an example of its
1678 Perl_hv_clear_placeholders(pTHX_ HV *hv)
1680 const U32 items = (U32)HvPLACEHOLDERS_get(hv);
1682 PERL_ARGS_ASSERT_HV_CLEAR_PLACEHOLDERS;
1685 clear_placeholders(hv, items);
1689 S_clear_placeholders(pTHX_ HV *hv, U32 items)
1694 PERL_ARGS_ASSERT_CLEAR_PLACEHOLDERS;
1701 /* Loop down the linked list heads */
1702 HE **oentry = &(HvARRAY(hv))[i];
1705 while ((entry = *oentry)) {
1706 if (HeVAL(entry) == &PL_sv_placeholder) {
1707 *oentry = HeNEXT(entry);
1708 if (entry == HvEITER_get(hv))
1711 if (SvOOK(hv) && HvLAZYDEL(hv) &&
1712 entry == HeNEXT(HvAUX(hv)->xhv_eiter))
1713 HeNEXT(HvAUX(hv)->xhv_eiter) = HeNEXT(entry);
1714 hv_free_ent(hv, entry);
1719 I32 placeholders = HvPLACEHOLDERS_get(hv);
1720 HvTOTALKEYS(hv) -= (IV)placeholders;
1721 /* HvUSEDKEYS expanded */
1722 if ((HvTOTALKEYS(hv) - placeholders) == 0)
1723 HvHASKFLAGS_off(hv);
1724 HvPLACEHOLDERS_set(hv, 0);
1728 oentry = &HeNEXT(entry);
1732 /* You can't get here, hence assertion should always fail. */
1733 assert (items == 0);
1734 NOT_REACHED; /* NOTREACHED */
1738 S_hfreeentries(pTHX_ HV *hv)
1741 XPVHV * const xhv = (XPVHV*)SvANY(hv);
1744 PERL_ARGS_ASSERT_HFREEENTRIES;
1746 while ((sv = Perl_hfree_next_entry(aTHX_ hv, &index))||xhv->xhv_keys) {
1752 /* hfree_next_entry()
1753 * For use only by S_hfreeentries() and sv_clear().
1754 * Delete the next available HE from hv and return the associated SV.
1755 * Returns null on empty hash. Nevertheless null is not a reliable
1756 * indicator that the hash is empty, as the deleted entry may have a
1758 * indexp is a pointer to the current index into HvARRAY. The index should
1759 * initially be set to 0. hfree_next_entry() may update it. */
1762 Perl_hfree_next_entry(pTHX_ HV *hv, STRLEN *indexp)
1764 struct xpvhv_aux *iter;
1768 STRLEN orig_index = *indexp;
1771 PERL_ARGS_ASSERT_HFREE_NEXT_ENTRY;
1773 if (SvOOK(hv) && ((iter = HvAUX(hv)))) {
1774 if ((entry = iter->xhv_eiter)) {
1775 /* the iterator may get resurrected after each
1776 * destructor call, so check each time */
1777 if (entry && HvLAZYDEL(hv)) { /* was deleted earlier? */
1779 hv_free_ent(hv, entry);
1780 /* warning: at this point HvARRAY may have been
1781 * re-allocated, HvMAX changed etc */
1783 iter = HvAUX(hv); /* may have been realloced */
1784 iter->xhv_riter = -1; /* HvRITER(hv) = -1 */
1785 iter->xhv_eiter = NULL; /* HvEITER(hv) = NULL */
1786 #ifdef PERL_HASH_RANDOMIZE_KEYS
1787 iter->xhv_last_rand = iter->xhv_rand;
1790 /* Reset any cached HvFILL() to "unknown". It's unlikely that anyone
1791 will actually call HvFILL() on a hash under destruction, so it
1792 seems pointless attempting to track the number of keys remaining.
1793 But if they do, we want to reset it again. */
1794 if (iter->xhv_fill_lazy)
1795 iter->xhv_fill_lazy = 0;
1798 if (!((XPVHV*)SvANY(hv))->xhv_keys)
1801 array = HvARRAY(hv);
1803 while ( ! ((entry = array[*indexp])) ) {
1804 if ((*indexp)++ >= HvMAX(hv))
1806 assert(*indexp != orig_index);
1808 array[*indexp] = HeNEXT(entry);
1809 ((XPVHV*) SvANY(hv))->xhv_keys--;
1811 if ( PL_phase != PERL_PHASE_DESTRUCT && HvENAME(hv)
1812 && HeVAL(entry) && isGV(HeVAL(entry))
1813 && GvHV(HeVAL(entry)) && HvENAME(GvHV(HeVAL(entry)))
1816 const char * const key = HePV(entry,klen);
1817 if ((klen > 1 && key[klen-1]==':' && key[klen-2]==':')
1818 || (klen == 1 && key[0] == ':')) {
1820 NULL, GvHV(HeVAL(entry)),
1821 (GV *)HeVAL(entry), 0
1825 return hv_free_ent_ret(hv, entry);
1830 =for apidoc hv_undef
1832 Undefines the hash. The XS equivalent of C<undef(%hash)>.
1834 As well as freeing all the elements of the hash (like C<hv_clear()>), this
1835 also frees any auxiliary data and storage associated with the hash.
1837 If any destructors are triggered as a result, the hv itself may
1840 See also L</hv_clear>.
1846 Perl_hv_undef_flags(pTHX_ HV *hv, U32 flags)
1853 save = !!SvREFCNT(hv);
1854 DEBUG_A(Perl_hv_assert(aTHX_ hv));
1855 xhv = (XPVHV*)SvANY(hv);
1857 /* The name must be deleted before the call to hfreeeeentries so that
1858 CVs are anonymised properly. But the effective name must be pre-
1859 served until after that call (and only deleted afterwards if the
1860 call originated from sv_clear). For stashes with one name that is
1861 both the canonical name and the effective name, hv_name_set has to
1862 allocate an array for storing the effective name. We can skip that
1863 during global destruction, as it does not matter where the CVs point
1864 if they will be freed anyway. */
1865 /* note that the code following prior to hfreeentries is duplicated
1866 * in sv_clear(), and changes here should be done there too */
1867 if (PL_phase != PERL_PHASE_DESTRUCT && HvNAME(hv)) {
1868 if (PL_stashcache) {
1869 DEBUG_o(Perl_deb(aTHX_ "hv_undef_flags clearing PL_stashcache for '%"
1870 HEKf"'\n", HEKfARG(HvNAME_HEK(hv))));
1871 (void)hv_deletehek(PL_stashcache, HvNAME_HEK(hv), G_DISCARD);
1873 hv_name_set(hv, NULL, 0, 0);
1877 SAVEFREESV(SvREFCNT_inc_simple_NN(hv));
1881 struct mro_meta *meta;
1884 if (HvENAME_get(hv)) {
1885 if (PL_phase != PERL_PHASE_DESTRUCT)
1886 mro_isa_changed_in(hv);
1887 if (PL_stashcache) {
1888 DEBUG_o(Perl_deb(aTHX_ "hv_undef_flags clearing PL_stashcache for effective name '%"
1889 HEKf"'\n", HEKfARG(HvENAME_HEK(hv))));
1890 (void)hv_deletehek(PL_stashcache, HvENAME_HEK(hv), G_DISCARD);
1894 /* If this call originated from sv_clear, then we must check for
1895 * effective names that need freeing, as well as the usual name. */
1897 if (flags & HV_NAME_SETALL ? !!HvAUX(hv)->xhv_name_u.xhvnameu_name : !!name) {
1898 if (name && PL_stashcache) {
1899 DEBUG_o(Perl_deb(aTHX_ "hv_undef_flags clearing PL_stashcache for name '%"
1900 HEKf"'\n", HEKfARG(HvNAME_HEK(hv))));
1901 (void)hv_deletehek(PL_stashcache, HvNAME_HEK(hv), G_DISCARD);
1903 hv_name_set(hv, NULL, 0, flags);
1905 if((meta = HvAUX(hv)->xhv_mro_meta)) {
1906 if (meta->mro_linear_all) {
1907 SvREFCNT_dec_NN(meta->mro_linear_all);
1908 /* mro_linear_current is just acting as a shortcut pointer,
1912 /* Only the current MRO is stored, so this owns the data.
1914 SvREFCNT_dec(meta->mro_linear_current);
1915 SvREFCNT_dec(meta->mro_nextmethod);
1916 SvREFCNT_dec(meta->isa);
1917 SvREFCNT_dec(meta->super);
1919 HvAUX(hv)->xhv_mro_meta = NULL;
1921 if (!HvAUX(hv)->xhv_name_u.xhvnameu_name && ! HvAUX(hv)->xhv_backreferences)
1922 SvFLAGS(hv) &= ~SVf_OOK;
1925 Safefree(HvARRAY(hv));
1926 xhv->xhv_max = PERL_HASH_DEFAULT_HvMAX; /* HvMAX(hv) = 7 (it's a normal hash) */
1929 /* if we're freeing the HV, the SvMAGIC field has been reused for
1930 * other purposes, and so there can't be any placeholder magic */
1932 HvPLACEHOLDERS_set(hv, 0);
1935 mg_clear(MUTABLE_SV(hv));
1942 Returns the number of hash buckets that
1943 happen to be in use. This function is
1944 wrapped by the macro C<HvFILL>.
1946 Previously this value was always stored in the HV structure, which created an
1947 overhead on every hash (and pretty much every object) for something that was
1948 rarely used. Now we calculate it on demand the first
1949 time that it is needed, and cache it if that calculation
1950 is going to be costly to repeat. The cached
1951 value is updated by insertions and deletions, but (currently) discarded if
1958 Perl_hv_fill(pTHX_ HV *const hv)
1961 HE **ents = HvARRAY(hv);
1962 struct xpvhv_aux *aux = SvOOK(hv) ? HvAUX(hv) : NULL;
1964 PERL_ARGS_ASSERT_HV_FILL;
1966 /* No keys implies no buckets used.
1967 One key can only possibly mean one bucket used. */
1968 if (HvTOTALKEYS(hv) < 2)
1969 return HvTOTALKEYS(hv);
1972 if (aux && aux->xhv_fill_lazy)
1973 return aux->xhv_fill_lazy;
1977 HE *const *const last = ents + HvMAX(hv);
1978 count = last + 1 - ents;
1983 } while (++ents <= last);
1987 if (aux->xhv_fill_lazy)
1988 assert(aux->xhv_fill_lazy == count);
1990 aux->xhv_fill_lazy = count;
1991 } else if (HvMAX(hv) >= HV_FILL_THRESHOLD) {
1992 aux = hv_auxinit(hv);
1993 aux->xhv_fill_lazy = count;
1998 /* hash a pointer to a U32 - Used in the hash traversal randomization
1999 * and bucket order randomization code
2001 * this code was derived from Sereal, which was derived from autobox.
2004 PERL_STATIC_INLINE U32 S_ptr_hash(PTRV u) {
2007 * This is one of Thomas Wang's hash functions for 64-bit integers from:
2008 * http://www.concentric.net/~Ttwang/tech/inthash.htm
2010 u = (~u) + (u << 18);
2018 * This is one of Bob Jenkins' hash functions for 32-bit integers
2019 * from: http://burtleburtle.net/bob/hash/integer.html
2021 u = (u + 0x7ed55d16) + (u << 12);
2022 u = (u ^ 0xc761c23c) ^ (u >> 19);
2023 u = (u + 0x165667b1) + (u << 5);
2024 u = (u + 0xd3a2646c) ^ (u << 9);
2025 u = (u + 0xfd7046c5) + (u << 3);
2026 u = (u ^ 0xb55a4f09) ^ (u >> 16);
2031 static struct xpvhv_aux*
2032 S_hv_auxinit_internal(struct xpvhv_aux *iter) {
2033 PERL_ARGS_ASSERT_HV_AUXINIT_INTERNAL;
2034 iter->xhv_riter = -1; /* HvRITER(hv) = -1 */
2035 iter->xhv_eiter = NULL; /* HvEITER(hv) = NULL */
2036 #ifdef PERL_HASH_RANDOMIZE_KEYS
2037 iter->xhv_last_rand = iter->xhv_rand;
2039 iter->xhv_fill_lazy = 0;
2040 iter->xhv_name_u.xhvnameu_name = 0;
2041 iter->xhv_name_count = 0;
2042 iter->xhv_backreferences = 0;
2043 iter->xhv_mro_meta = NULL;
2044 iter->xhv_aux_flags = 0;
2049 static struct xpvhv_aux*
2050 S_hv_auxinit(pTHX_ HV *hv) {
2051 struct xpvhv_aux *iter;
2054 PERL_ARGS_ASSERT_HV_AUXINIT;
2058 Newxz(array, PERL_HV_ARRAY_ALLOC_BYTES(HvMAX(hv) + 1)
2059 + sizeof(struct xpvhv_aux), char);
2061 array = (char *) HvARRAY(hv);
2062 Renew(array, PERL_HV_ARRAY_ALLOC_BYTES(HvMAX(hv) + 1)
2063 + sizeof(struct xpvhv_aux), char);
2065 HvARRAY(hv) = (HE**)array;
2068 #ifdef PERL_HASH_RANDOMIZE_KEYS
2069 if (PL_HASH_RAND_BITS_ENABLED) {
2070 /* mix in some new state to PL_hash_rand_bits to "randomize" the traversal order*/
2071 if (PL_HASH_RAND_BITS_ENABLED == 1)
2072 PL_hash_rand_bits += ptr_hash((PTRV)array);
2073 PL_hash_rand_bits = ROTL_UV(PL_hash_rand_bits,1);
2075 iter->xhv_rand = (U32)PL_hash_rand_bits;
2081 return hv_auxinit_internal(iter);
2085 =for apidoc hv_iterinit
2087 Prepares a starting point to traverse a hash table. Returns the number of
2088 keys in the hash (i.e. the same as C<HvUSEDKEYS(hv)>). The return value is
2089 currently only meaningful for hashes without tie magic.
2091 NOTE: Before version 5.004_65, C<hv_iterinit> used to return the number of
2092 hash buckets that happen to be in use. If you still need that esoteric
2093 value, you can get it through the macro C<HvFILL(hv)>.
2100 Perl_hv_iterinit(pTHX_ HV *hv)
2102 PERL_ARGS_ASSERT_HV_ITERINIT;
2105 struct xpvhv_aux * iter = HvAUX(hv);
2106 HE * const entry = iter->xhv_eiter; /* HvEITER(hv) */
2107 if (entry && HvLAZYDEL(hv)) { /* was deleted earlier? */
2109 hv_free_ent(hv, entry);
2111 iter = HvAUX(hv); /* may have been reallocated */
2112 iter->xhv_riter = -1; /* HvRITER(hv) = -1 */
2113 iter->xhv_eiter = NULL; /* HvEITER(hv) = NULL */
2114 #ifdef PERL_HASH_RANDOMIZE_KEYS
2115 iter->xhv_last_rand = iter->xhv_rand;
2121 /* used to be xhv->xhv_fill before 5.004_65 */
2122 return HvTOTALKEYS(hv);
2126 Perl_hv_riter_p(pTHX_ HV *hv) {
2127 struct xpvhv_aux *iter;
2129 PERL_ARGS_ASSERT_HV_RITER_P;
2131 iter = SvOOK(hv) ? HvAUX(hv) : hv_auxinit(hv);
2132 return &(iter->xhv_riter);
2136 Perl_hv_eiter_p(pTHX_ HV *hv) {
2137 struct xpvhv_aux *iter;
2139 PERL_ARGS_ASSERT_HV_EITER_P;
2141 iter = SvOOK(hv) ? HvAUX(hv) : hv_auxinit(hv);
2142 return &(iter->xhv_eiter);
2146 Perl_hv_riter_set(pTHX_ HV *hv, I32 riter) {
2147 struct xpvhv_aux *iter;
2149 PERL_ARGS_ASSERT_HV_RITER_SET;
2157 iter = hv_auxinit(hv);
2159 iter->xhv_riter = riter;
2163 Perl_hv_rand_set(pTHX_ HV *hv, U32 new_xhv_rand) {
2164 struct xpvhv_aux *iter;
2166 PERL_ARGS_ASSERT_HV_RAND_SET;
2168 #ifdef PERL_HASH_RANDOMIZE_KEYS
2172 iter = hv_auxinit(hv);
2174 iter->xhv_rand = new_xhv_rand;
2176 Perl_croak(aTHX_ "This Perl has not been built with support for randomized hash key traversal but something called Perl_hv_rand_set().");
2181 Perl_hv_eiter_set(pTHX_ HV *hv, HE *eiter) {
2182 struct xpvhv_aux *iter;
2184 PERL_ARGS_ASSERT_HV_EITER_SET;
2189 /* 0 is the default so don't go malloc()ing a new structure just to
2194 iter = hv_auxinit(hv);
2196 iter->xhv_eiter = eiter;
2200 Perl_hv_name_set(pTHX_ HV *hv, const char *name, U32 len, U32 flags)
2203 struct xpvhv_aux *iter;
2207 PERL_ARGS_ASSERT_HV_NAME_SET;
2210 Perl_croak(aTHX_ "panic: hv name too long (%"UVuf")", (UV) len);
2214 if (iter->xhv_name_u.xhvnameu_name) {
2215 if(iter->xhv_name_count) {
2216 if(flags & HV_NAME_SETALL) {
2217 HEK ** const name = HvAUX(hv)->xhv_name_u.xhvnameu_names;
2218 HEK **hekp = name + (
2219 iter->xhv_name_count < 0
2220 ? -iter->xhv_name_count
2221 : iter->xhv_name_count
2223 while(hekp-- > name+1)
2224 unshare_hek_or_pvn(*hekp, 0, 0, 0);
2225 /* The first elem may be null. */
2226 if(*name) unshare_hek_or_pvn(*name, 0, 0, 0);
2228 iter = HvAUX(hv); /* may been realloced */
2229 spot = &iter->xhv_name_u.xhvnameu_name;
2230 iter->xhv_name_count = 0;
2233 if(iter->xhv_name_count > 0) {
2234 /* shift some things over */
2236 iter->xhv_name_u.xhvnameu_names, iter->xhv_name_count + 1, HEK *
2238 spot = iter->xhv_name_u.xhvnameu_names;
2239 spot[iter->xhv_name_count] = spot[1];
2241 iter->xhv_name_count = -(iter->xhv_name_count + 1);
2243 else if(*(spot = iter->xhv_name_u.xhvnameu_names)) {
2244 unshare_hek_or_pvn(*spot, 0, 0, 0);
2248 else if (flags & HV_NAME_SETALL) {
2249 unshare_hek_or_pvn(iter->xhv_name_u.xhvnameu_name, 0, 0, 0);
2250 iter = HvAUX(hv); /* may been realloced */
2251 spot = &iter->xhv_name_u.xhvnameu_name;
2254 HEK * const existing_name = iter->xhv_name_u.xhvnameu_name;
2255 Newx(iter->xhv_name_u.xhvnameu_names, 2, HEK *);
2256 iter->xhv_name_count = -2;
2257 spot = iter->xhv_name_u.xhvnameu_names;
2258 spot[1] = existing_name;
2261 else { spot = &iter->xhv_name_u.xhvnameu_name; iter->xhv_name_count = 0; }
2266 iter = hv_auxinit(hv);
2267 spot = &iter->xhv_name_u.xhvnameu_name;
2269 PERL_HASH(hash, name, len);
2270 *spot = name ? share_hek(name, flags & SVf_UTF8 ? -(I32)len : (I32)len, hash) : NULL;
2274 This is basically sv_eq_flags() in sv.c, but we avoid the magic
2279 hek_eq_pvn_flags(pTHX_ const HEK *hek, const char* pv, const I32 pvlen, const U32 flags) {
2280 if ( (HEK_UTF8(hek) ? 1 : 0) != (flags & SVf_UTF8 ? 1 : 0) ) {
2281 if (flags & SVf_UTF8)
2282 return (bytes_cmp_utf8(
2283 (const U8*)HEK_KEY(hek), HEK_LEN(hek),
2284 (const U8*)pv, pvlen) == 0);
2286 return (bytes_cmp_utf8(
2287 (const U8*)pv, pvlen,
2288 (const U8*)HEK_KEY(hek), HEK_LEN(hek)) == 0);
2291 return HEK_LEN(hek) == pvlen && ((HEK_KEY(hek) == pv)
2292 || memEQ(HEK_KEY(hek), pv, pvlen));
2296 =for apidoc hv_ename_add
2298 Adds a name to a stash's internal list of effective names. See
2299 C<L</hv_ename_delete>>.
2301 This is called when a stash is assigned to a new location in the symbol
2308 Perl_hv_ename_add(pTHX_ HV *hv, const char *name, U32 len, U32 flags)
2311 struct xpvhv_aux *aux = SvOOK(hv) ? HvAUX(hv) : hv_auxinit(hv);
2314 PERL_ARGS_ASSERT_HV_ENAME_ADD;
2317 Perl_croak(aTHX_ "panic: hv name too long (%"UVuf")", (UV) len);
2319 PERL_HASH(hash, name, len);
2321 if (aux->xhv_name_count) {
2322 I32 count = aux->xhv_name_count;
2323 HEK ** const xhv_name = aux->xhv_name_u.xhvnameu_names + (count<0);
2324 HEK **hekp = xhv_name + (count < 0 ? -count - 1 : count);
2325 while (hekp-- > xhv_name)
2329 (HEK_UTF8(*hekp) || (flags & SVf_UTF8))
2330 ? hek_eq_pvn_flags(aTHX_ *hekp, name, (I32)len, flags)
2331 : (HEK_LEN(*hekp) == (I32)len && memEQ(HEK_KEY(*hekp), name, len))
2333 if (hekp == xhv_name && count < 0)
2334 aux->xhv_name_count = -count;
2338 if (count < 0) aux->xhv_name_count--, count = -count;
2339 else aux->xhv_name_count++;
2340 Renew(aux->xhv_name_u.xhvnameu_names, count + 1, HEK *);
2341 (aux->xhv_name_u.xhvnameu_names)[count] = share_hek(name, (flags & SVf_UTF8 ? -(I32)len : (I32)len), hash);
2344 HEK *existing_name = aux->xhv_name_u.xhvnameu_name;
2347 (HEK_UTF8(existing_name) || (flags & SVf_UTF8))
2348 ? hek_eq_pvn_flags(aTHX_ existing_name, name, (I32)len, flags)
2349 : (HEK_LEN(existing_name) == (I32)len && memEQ(HEK_KEY(existing_name), name, len))
2352 Newx(aux->xhv_name_u.xhvnameu_names, 2, HEK *);
2353 aux->xhv_name_count = existing_name ? 2 : -2;
2354 *aux->xhv_name_u.xhvnameu_names = existing_name;
2355 (aux->xhv_name_u.xhvnameu_names)[1] = share_hek(name, (flags & SVf_UTF8 ? -(I32)len : (I32)len), hash);
2360 =for apidoc hv_ename_delete
2362 Removes a name from a stash's internal list of effective names. If this is
2363 the name returned by C<HvENAME>, then another name in the list will take
2364 its place (C<HvENAME> will use it).
2366 This is called when a stash is deleted from the symbol table.
2372 Perl_hv_ename_delete(pTHX_ HV *hv, const char *name, U32 len, U32 flags)
2374 struct xpvhv_aux *aux;
2376 PERL_ARGS_ASSERT_HV_ENAME_DELETE;
2379 Perl_croak(aTHX_ "panic: hv name too long (%"UVuf")", (UV) len);
2381 if (!SvOOK(hv)) return;
2384 if (!aux->xhv_name_u.xhvnameu_name) return;
2386 if (aux->xhv_name_count) {
2387 HEK ** const namep = aux->xhv_name_u.xhvnameu_names;
2388 I32 const count = aux->xhv_name_count;
2389 HEK **victim = namep + (count < 0 ? -count : count);
2390 while (victim-- > namep + 1)
2392 (HEK_UTF8(*victim) || (flags & SVf_UTF8))
2393 ? hek_eq_pvn_flags(aTHX_ *victim, name, (I32)len, flags)
2394 : (HEK_LEN(*victim) == (I32)len && memEQ(HEK_KEY(*victim), name, len))
2396 unshare_hek_or_pvn(*victim, 0, 0, 0);
2397 aux = HvAUX(hv); /* may been realloced */
2398 if (count < 0) ++aux->xhv_name_count;
2399 else --aux->xhv_name_count;
2401 (aux->xhv_name_count == 1 || aux->xhv_name_count == -1)
2403 ) { /* if there are none left */
2405 aux->xhv_name_u.xhvnameu_names = NULL;
2406 aux->xhv_name_count = 0;
2409 /* Move the last one back to fill the empty slot. It
2410 does not matter what order they are in. */
2411 *victim = *(namep + (count < 0 ? -count : count) - 1);
2416 count > 0 && (HEK_UTF8(*namep) || (flags & SVf_UTF8))
2417 ? hek_eq_pvn_flags(aTHX_ *namep, name, (I32)len, flags)
2418 : (HEK_LEN(*namep) == (I32)len && memEQ(HEK_KEY(*namep), name, len))
2420 aux->xhv_name_count = -count;
2424 (HEK_UTF8(aux->xhv_name_u.xhvnameu_name) || (flags & SVf_UTF8))
2425 ? hek_eq_pvn_flags(aTHX_ aux->xhv_name_u.xhvnameu_name, name, (I32)len, flags)
2426 : (HEK_LEN(aux->xhv_name_u.xhvnameu_name) == (I32)len &&
2427 memEQ(HEK_KEY(aux->xhv_name_u.xhvnameu_name), name, len))
2429 HEK * const namehek = aux->xhv_name_u.xhvnameu_name;
2430 Newx(aux->xhv_name_u.xhvnameu_names, 1, HEK *);
2431 *aux->xhv_name_u.xhvnameu_names = namehek;
2432 aux->xhv_name_count = -1;
2437 Perl_hv_backreferences_p(pTHX_ HV *hv) {
2438 PERL_ARGS_ASSERT_HV_BACKREFERENCES_P;
2439 /* See also Perl_sv_get_backrefs in sv.c where this logic is unrolled */
2441 struct xpvhv_aux * const iter = SvOOK(hv) ? HvAUX(hv) : hv_auxinit(hv);
2442 return &(iter->xhv_backreferences);
2447 Perl_hv_kill_backrefs(pTHX_ HV *hv) {
2450 PERL_ARGS_ASSERT_HV_KILL_BACKREFS;
2455 av = HvAUX(hv)->xhv_backreferences;
2458 HvAUX(hv)->xhv_backreferences = 0;
2459 Perl_sv_kill_backrefs(aTHX_ MUTABLE_SV(hv), av);
2460 if (SvTYPE(av) == SVt_PVAV)
2461 SvREFCNT_dec_NN(av);
2466 hv_iternext is implemented as a macro in hv.h
2468 =for apidoc hv_iternext
2470 Returns entries from a hash iterator. See C<L</hv_iterinit>>.
2472 You may call C<hv_delete> or C<hv_delete_ent> on the hash entry that the
2473 iterator currently points to, without losing your place or invalidating your
2474 iterator. Note that in this case the current entry is deleted from the hash
2475 with your iterator holding the last reference to it. Your iterator is flagged
2476 to free the entry on the next call to C<hv_iternext>, so you must not discard
2477 your iterator immediately else the entry will leak - call C<hv_iternext> to
2478 trigger the resource deallocation.
2480 =for apidoc hv_iternext_flags
2482 Returns entries from a hash iterator. See C<L</hv_iterinit>> and
2484 The C<flags> value will normally be zero; if C<HV_ITERNEXT_WANTPLACEHOLDERS> is
2485 set the placeholders keys (for restricted hashes) will be returned in addition
2486 to normal keys. By default placeholders are automatically skipped over.
2487 Currently a placeholder is implemented with a value that is
2488 C<&PL_sv_placeholder>. Note that the implementation of placeholders and
2489 restricted hashes may change, and the implementation currently is
2490 insufficiently abstracted for any change to be tidy.
2496 Perl_hv_iternext_flags(pTHX_ HV *hv, I32 flags)
2503 struct xpvhv_aux *iter;
2505 PERL_ARGS_ASSERT_HV_ITERNEXT_FLAGS;
2507 xhv = (XPVHV*)SvANY(hv);
2510 /* Too many things (well, pp_each at least) merrily assume that you can
2511 call hv_iternext without calling hv_iterinit, so we'll have to deal
2517 oldentry = entry = iter->xhv_eiter; /* HvEITER(hv) */
2518 if (SvMAGICAL(hv) && SvRMAGICAL(hv)) {
2519 if ( ( mg = mg_find((const SV *)hv, PERL_MAGIC_tied) ) ) {
2520 SV * const key = sv_newmortal();
2522 sv_setsv(key, HeSVKEY_force(entry));
2523 SvREFCNT_dec(HeSVKEY(entry)); /* get rid of previous key */
2524 HeSVKEY_set(entry, NULL);
2530 /* one HE per MAGICAL hash */
2531 iter->xhv_eiter = entry = new_HE(); /* HvEITER(hv) = new_HE() */
2532 HvLAZYDEL_on(hv); /* make sure entry gets freed */
2534 Newxz(k, HEK_BASESIZE + sizeof(const SV *), char);
2536 HeKEY_hek(entry) = hek;
2537 HeKLEN(entry) = HEf_SVKEY;
2539 magic_nextpack(MUTABLE_SV(hv),mg,key);
2541 /* force key to stay around until next time */
2542 HeSVKEY_set(entry, SvREFCNT_inc_simple_NN(key));
2543 return entry; /* beware, hent_val is not set */
2545 SvREFCNT_dec(HeVAL(entry));
2546 Safefree(HeKEY_hek(entry));
2548 iter = HvAUX(hv); /* may been realloced */
2549 iter->xhv_eiter = NULL; /* HvEITER(hv) = NULL */
2554 #if defined(DYNAMIC_ENV_FETCH) && !defined(__riscos__) /* set up %ENV for iteration */
2555 if (!entry && SvRMAGICAL((const SV *)hv)
2556 && mg_find((const SV *)hv, PERL_MAGIC_env)) {
2559 /* The prime_env_iter() on VMS just loaded up new hash values
2560 * so the iteration count needs to be reset back to the beginning
2564 oldentry = entry = iter->xhv_eiter; /* HvEITER(hv) */
2569 /* hv_iterinit now ensures this. */
2570 assert (HvARRAY(hv));
2572 /* At start of hash, entry is NULL. */
2575 entry = HeNEXT(entry);
2576 if (!(flags & HV_ITERNEXT_WANTPLACEHOLDERS)) {
2578 * Skip past any placeholders -- don't want to include them in
2581 while (entry && HeVAL(entry) == &PL_sv_placeholder) {
2582 entry = HeNEXT(entry);
2587 #ifdef PERL_HASH_RANDOMIZE_KEYS
2588 if (iter->xhv_last_rand != iter->xhv_rand) {
2589 if (iter->xhv_riter != -1) {
2590 Perl_ck_warner_d(aTHX_ packWARN(WARN_INTERNAL),
2591 "Use of each() on hash after insertion without resetting hash iterator results in undefined behavior"
2595 iter = HvAUX(hv); /* may been realloced */
2596 iter->xhv_last_rand = iter->xhv_rand;
2600 /* Skip the entire loop if the hash is empty. */
2601 if ((flags & HV_ITERNEXT_WANTPLACEHOLDERS)
2602 ? HvTOTALKEYS(hv) : HvUSEDKEYS(hv)) {
2604 /* OK. Come to the end of the current list. Grab the next one. */
2606 iter->xhv_riter++; /* HvRITER(hv)++ */
2607 if (iter->xhv_riter > (I32)xhv->xhv_max /* HvRITER(hv) > HvMAX(hv) */) {
2608 /* There is no next one. End of the hash. */
2609 iter->xhv_riter = -1; /* HvRITER(hv) = -1 */
2610 #ifdef PERL_HASH_RANDOMIZE_KEYS
2611 iter->xhv_last_rand = iter->xhv_rand; /* reset xhv_last_rand so we can detect inserts during traversal */
2615 entry = (HvARRAY(hv))[ PERL_HASH_ITER_BUCKET(iter) & xhv->xhv_max ];
2617 if (!(flags & HV_ITERNEXT_WANTPLACEHOLDERS)) {
2618 /* If we have an entry, but it's a placeholder, don't count it.
2620 while (entry && HeVAL(entry) == &PL_sv_placeholder)
2621 entry = HeNEXT(entry);
2623 /* Will loop again if this linked list starts NULL
2624 (for HV_ITERNEXT_WANTPLACEHOLDERS)
2625 or if we run through it and find only placeholders. */
2629 iter->xhv_riter = -1;
2630 #ifdef PERL_HASH_RANDOMIZE_KEYS
2631 iter->xhv_last_rand = iter->xhv_rand;
2635 if (oldentry && HvLAZYDEL(hv)) { /* was deleted earlier? */
2637 hv_free_ent(hv, oldentry);
2640 iter = HvAUX(hv); /* may been realloced */
2641 iter->xhv_eiter = entry; /* HvEITER(hv) = entry */
2646 =for apidoc hv_iterkey
2648 Returns the key from the current position of the hash iterator. See
2655 Perl_hv_iterkey(pTHX_ HE *entry, I32 *retlen)
2657 PERL_ARGS_ASSERT_HV_ITERKEY;
2659 if (HeKLEN(entry) == HEf_SVKEY) {
2661 char * const p = SvPV(HeKEY_sv(entry), len);
2666 *retlen = HeKLEN(entry);
2667 return HeKEY(entry);
2671 /* unlike hv_iterval(), this always returns a mortal copy of the key */
2673 =for apidoc hv_iterkeysv
2675 Returns the key as an C<SV*> from the current position of the hash
2676 iterator. The return value will always be a mortal copy of the key. Also
2677 see C<L</hv_iterinit>>.
2683 Perl_hv_iterkeysv(pTHX_ HE *entry)
2685 PERL_ARGS_ASSERT_HV_ITERKEYSV;
2687 return sv_2mortal(newSVhek(HeKEY_hek(entry)));
2691 =for apidoc hv_iterval
2693 Returns the value from the current position of the hash iterator. See
2700 Perl_hv_iterval(pTHX_ HV *hv, HE *entry)
2702 PERL_ARGS_ASSERT_HV_ITERVAL;
2704 if (SvRMAGICAL(hv)) {
2705 if (mg_find((const SV *)hv, PERL_MAGIC_tied)) {
2706 SV* const sv = sv_newmortal();
2707 if (HeKLEN(entry) == HEf_SVKEY)
2708 mg_copy(MUTABLE_SV(hv), sv, (char*)HeKEY_sv(entry), HEf_SVKEY);
2710 mg_copy(MUTABLE_SV(hv), sv, HeKEY(entry), HeKLEN(entry));
2714 return HeVAL(entry);
2718 =for apidoc hv_iternextsv
2720 Performs an C<hv_iternext>, C<hv_iterkey>, and C<hv_iterval> in one
2727 Perl_hv_iternextsv(pTHX_ HV *hv, char **key, I32 *retlen)
2729 HE * const he = hv_iternext_flags(hv, 0);
2731 PERL_ARGS_ASSERT_HV_ITERNEXTSV;
2735 *key = hv_iterkey(he, retlen);
2736 return hv_iterval(hv, he);
2743 =for apidoc hv_magic
2745 Adds magic to a hash. See C<L</sv_magic>>.
2750 /* possibly free a shared string if no one has access to it
2751 * len and hash must both be valid for str.
2754 Perl_unsharepvn(pTHX_ const char *str, I32 len, U32 hash)
2756 unshare_hek_or_pvn (NULL, str, len, hash);
2761 Perl_unshare_hek(pTHX_ HEK *hek)
2764 unshare_hek_or_pvn(hek, NULL, 0, 0);
2767 /* possibly free a shared string if no one has access to it
2768 hek if non-NULL takes priority over the other 3, else str, len and hash
2769 are used. If so, len and hash must both be valid for str.
2772 S_unshare_hek_or_pvn(pTHX_ const HEK *hek, const char *str, I32 len, U32 hash)
2777 bool is_utf8 = FALSE;
2779 const char * const save = str;
2780 struct shared_he *he = NULL;
2783 /* Find the shared he which is just before us in memory. */
2784 he = (struct shared_he *)(((char *)hek)
2785 - STRUCT_OFFSET(struct shared_he,
2788 /* Assert that the caller passed us a genuine (or at least consistent)
2790 assert (he->shared_he_he.hent_hek == hek);
2792 if (he->shared_he_he.he_valu.hent_refcount - 1) {
2793 --he->shared_he_he.he_valu.hent_refcount;
2797 hash = HEK_HASH(hek);
2798 } else if (len < 0) {
2799 STRLEN tmplen = -len;
2801 /* See the note in hv_fetch(). --jhi */
2802 str = (char*)bytes_from_utf8((U8*)str, &tmplen, &is_utf8);
2805 k_flags = HVhek_UTF8;
2807 k_flags |= HVhek_WASUTF8 | HVhek_FREEKEY;
2810 /* what follows was the moral equivalent of:
2811 if ((Svp = hv_fetch(PL_strtab, tmpsv, FALSE, hash))) {
2813 hv_delete(PL_strtab, str, len, G_DISCARD, hash);
2815 xhv = (XPVHV*)SvANY(PL_strtab);
2816 /* assert(xhv_array != 0) */
2817 oentry = &(HvARRAY(PL_strtab))[hash & (I32) HvMAX(PL_strtab)];
2819 const HE *const he_he = &(he->shared_he_he);
2820 for (entry = *oentry; entry; oentry = &HeNEXT(entry), entry = *oentry) {
2825 const int flags_masked = k_flags & HVhek_MASK;
2826 for (entry = *oentry; entry; oentry = &HeNEXT(entry), entry = *oentry) {
2827 if (HeHASH(entry) != hash) /* strings can't be equal */
2829 if (HeKLEN(entry) != len)
2831 if (HeKEY(entry) != str && memNE(HeKEY(entry),str,len)) /* is this it? */
2833 if (HeKFLAGS(entry) != flags_masked)
2840 if (--entry->he_valu.hent_refcount == 0) {
2841 *oentry = HeNEXT(entry);
2843 xhv->xhv_keys--; /* HvTOTALKEYS(hv)-- */
2848 Perl_ck_warner_d(aTHX_ packWARN(WARN_INTERNAL),
2849 "Attempt to free nonexistent shared string '%s'%s"
2851 hek ? HEK_KEY(hek) : str,
2852 ((k_flags & HVhek_UTF8) ? " (utf8)" : "") pTHX__VALUE);
2853 if (k_flags & HVhek_FREEKEY)
2857 /* get a (constant) string ptr from the global string table
2858 * string will get added if it is not already there.
2859 * len and hash must both be valid for str.
2862 Perl_share_hek(pTHX_ const char *str, I32 len, U32 hash)
2864 bool is_utf8 = FALSE;
2866 const char * const save = str;
2868 PERL_ARGS_ASSERT_SHARE_HEK;
2871 STRLEN tmplen = -len;
2873 /* See the note in hv_fetch(). --jhi */
2874 str = (char*)bytes_from_utf8((U8*)str, &tmplen, &is_utf8);
2876 /* If we were able to downgrade here, then than means that we were passed
2877 in a key which only had chars 0-255, but was utf8 encoded. */
2880 /* If we found we were able to downgrade the string to bytes, then
2881 we should flag that it needs upgrading on keys or each. Also flag
2882 that we need share_hek_flags to free the string. */
2885 PERL_HASH(hash, str, len);
2886 flags |= HVhek_WASUTF8 | HVhek_FREEKEY;
2890 return share_hek_flags (str, len, hash, flags);
2894 S_share_hek_flags(pTHX_ const char *str, I32 len, U32 hash, int flags)
2897 const int flags_masked = flags & HVhek_MASK;
2898 const U32 hindex = hash & (I32) HvMAX(PL_strtab);
2899 XPVHV * const xhv = (XPVHV*)SvANY(PL_strtab);
2901 PERL_ARGS_ASSERT_SHARE_HEK_FLAGS;
2903 /* what follows is the moral equivalent of:
2905 if (!(Svp = hv_fetch(PL_strtab, str, len, FALSE)))
2906 hv_store(PL_strtab, str, len, NULL, hash);
2908 Can't rehash the shared string table, so not sure if it's worth
2909 counting the number of entries in the linked list
2912 /* assert(xhv_array != 0) */
2913 entry = (HvARRAY(PL_strtab))[hindex];
2914 for (;entry; entry = HeNEXT(entry)) {
2915 if (HeHASH(entry) != hash) /* strings can't be equal */
2917 if (HeKLEN(entry) != len)
2919 if (HeKEY(entry) != str && memNE(HeKEY(entry),str,len)) /* is this it? */
2921 if (HeKFLAGS(entry) != flags_masked)
2927 /* What used to be head of the list.
2928 If this is NULL, then we're the first entry for this slot, which
2929 means we need to increate fill. */
2930 struct shared_he *new_entry;
2933 HE **const head = &HvARRAY(PL_strtab)[hindex];
2934 HE *const next = *head;
2936 /* We don't actually store a HE from the arena and a regular HEK.
2937 Instead we allocate one chunk of memory big enough for both,
2938 and put the HEK straight after the HE. This way we can find the
2939 HE directly from the HEK.
2942 Newx(k, STRUCT_OFFSET(struct shared_he,
2943 shared_he_hek.hek_key[0]) + len + 2, char);
2944 new_entry = (struct shared_he *)k;
2945 entry = &(new_entry->shared_he_he);
2946 hek = &(new_entry->shared_he_hek);
2948 Copy(str, HEK_KEY(hek), len, char);
2949 HEK_KEY(hek)[len] = 0;
2951 HEK_HASH(hek) = hash;
2952 HEK_FLAGS(hek) = (unsigned char)flags_masked;
2954 /* Still "point" to the HEK, so that other code need not know what
2956 HeKEY_hek(entry) = hek;
2957 entry->he_valu.hent_refcount = 0;
2958 HeNEXT(entry) = next;
2961 xhv->xhv_keys++; /* HvTOTALKEYS(hv)++ */
2962 if (!next) { /* initial entry? */
2963 } else if ( DO_HSPLIT(xhv) ) {
2964 const STRLEN oldsize = xhv->xhv_max + 1;
2965 hsplit(PL_strtab, oldsize, oldsize * 2);
2969 ++entry->he_valu.hent_refcount;
2971 if (flags & HVhek_FREEKEY)
2974 return HeKEY_hek(entry);
2978 Perl_hv_placeholders_p(pTHX_ HV *hv)
2980 MAGIC *mg = mg_find((const SV *)hv, PERL_MAGIC_rhash);
2982 PERL_ARGS_ASSERT_HV_PLACEHOLDERS_P;
2985 mg = sv_magicext(MUTABLE_SV(hv), 0, PERL_MAGIC_rhash, 0, 0, 0);
2988 Perl_die(aTHX_ "panic: hv_placeholders_p");
2991 return &(mg->mg_len);
2996 Perl_hv_placeholders_get(pTHX_ const HV *hv)
2998 MAGIC * const mg = mg_find((const SV *)hv, PERL_MAGIC_rhash);
3000 PERL_ARGS_ASSERT_HV_PLACEHOLDERS_GET;
3001 PERL_UNUSED_CONTEXT;
3003 return mg ? mg->mg_len : 0;
3007 Perl_hv_placeholders_set(pTHX_ HV *hv, I32 ph)
3009 MAGIC * const mg = mg_find((const SV *)hv, PERL_MAGIC_rhash);
3011 PERL_ARGS_ASSERT_HV_PLACEHOLDERS_SET;
3016 if (!sv_magicext(MUTABLE_SV(hv), 0, PERL_MAGIC_rhash, 0, 0, ph))
3017 Perl_die(aTHX_ "panic: hv_placeholders_set");
3019 /* else we don't need to add magic to record 0 placeholders. */
3023 S_refcounted_he_value(pTHX_ const struct refcounted_he *he)
3028 PERL_ARGS_ASSERT_REFCOUNTED_HE_VALUE;
3030 switch(he->refcounted_he_data[0] & HVrhek_typemask) {
3035 value = &PL_sv_placeholder;
3038 value = newSViv(he->refcounted_he_val.refcounted_he_u_iv);
3041 value = newSVuv(he->refcounted_he_val.refcounted_he_u_uv);
3044 case HVrhek_PV_UTF8:
3045 /* Create a string SV that directly points to the bytes in our
3047 value = newSV_type(SVt_PV);
3048 SvPV_set(value, (char *) he->refcounted_he_data + 1);
3049 SvCUR_set(value, he->refcounted_he_val.refcounted_he_u_len);
3050 /* This stops anything trying to free it */
3051 SvLEN_set(value, 0);
3053 SvREADONLY_on(value);
3054 if ((he->refcounted_he_data[0] & HVrhek_typemask) == HVrhek_PV_UTF8)
3058 Perl_croak(aTHX_ "panic: refcounted_he_value bad flags %"UVxf,
3059 (UV)he->refcounted_he_data[0]);
3065 =for apidoc m|HV *|refcounted_he_chain_2hv|const struct refcounted_he *c|U32 flags
3067 Generates and returns a C<HV *> representing the content of a
3068 C<refcounted_he> chain.
3069 C<flags> is currently unused and must be zero.
3074 Perl_refcounted_he_chain_2hv(pTHX_ const struct refcounted_he *chain, U32 flags)
3078 U32 placeholders, max;
3081 Perl_croak(aTHX_ "panic: refcounted_he_chain_2hv bad flags %"UVxf,
3084 /* We could chase the chain once to get an idea of the number of keys,
3085 and call ksplit. But for now we'll make a potentially inefficient
3086 hash with only 8 entries in its array. */
3091 Newxz(array, PERL_HV_ARRAY_ALLOC_BYTES(max + 1), char);
3092 HvARRAY(hv) = (HE**)array;
3098 U32 hash = chain->refcounted_he_hash;
3100 U32 hash = HEK_HASH(chain->refcounted_he_hek);
3102 HE **oentry = &((HvARRAY(hv))[hash & max]);
3103 HE *entry = *oentry;
3106 for (; entry; entry = HeNEXT(entry)) {
3107 if (HeHASH(entry) == hash) {
3108 /* We might have a duplicate key here. If so, entry is older
3109 than the key we've already put in the hash, so if they are
3110 the same, skip adding entry. */
3112 const STRLEN klen = HeKLEN(entry);
3113 const char *const key = HeKEY(entry);
3114 if (klen == chain->refcounted_he_keylen
3115 && (!!HeKUTF8(entry)
3116 == !!(chain->refcounted_he_data[0] & HVhek_UTF8))
3117 && memEQ(key, REF_HE_KEY(chain), klen))
3120 if (HeKEY_hek(entry) == chain->refcounted_he_hek)
3122 if (HeKLEN(entry) == HEK_LEN(chain->refcounted_he_hek)
3123 && HeKUTF8(entry) == HEK_UTF8(chain->refcounted_he_hek)
3124 && memEQ(HeKEY(entry), HEK_KEY(chain->refcounted_he_hek),
3135 = share_hek_flags(REF_HE_KEY(chain),
3136 chain->refcounted_he_keylen,
3137 chain->refcounted_he_hash,
3138 (chain->refcounted_he_data[0]
3139 & (HVhek_UTF8|HVhek_WASUTF8)));
3141 HeKEY_hek(entry) = share_hek_hek(chain->refcounted_he_hek);
3143 value = refcounted_he_value(chain);
3144 if (value == &PL_sv_placeholder)
3146 HeVAL(entry) = value;
3148 /* Link it into the chain. */
3149 HeNEXT(entry) = *oentry;
3155 chain = chain->refcounted_he_next;
3159 clear_placeholders(hv, placeholders);
3160 HvTOTALKEYS(hv) -= placeholders;
3163 /* We could check in the loop to see if we encounter any keys with key
3164 flags, but it's probably not worth it, as this per-hash flag is only
3165 really meant as an optimisation for things like Storable. */
3167 DEBUG_A(Perl_hv_assert(aTHX_ hv));
3173 =for apidoc m|SV *|refcounted_he_fetch_pvn|const struct refcounted_he *chain|const char *keypv|STRLEN keylen|U32 hash|U32 flags
3175 Search along a C<refcounted_he> chain for an entry with the key specified
3176 by C<keypv> and C<keylen>. If C<flags> has the C<REFCOUNTED_HE_KEY_UTF8>
3177 bit set, the key octets are interpreted as UTF-8, otherwise they
3178 are interpreted as Latin-1. C<hash> is a precomputed hash of the key
3179 string, or zero if it has not been precomputed. Returns a mortal scalar
3180 representing the value associated with the key, or C<&PL_sv_placeholder>
3181 if there is no value associated with the key.
3187 Perl_refcounted_he_fetch_pvn(pTHX_ const struct refcounted_he *chain,
3188 const char *keypv, STRLEN keylen, U32 hash, U32 flags)
3192 PERL_ARGS_ASSERT_REFCOUNTED_HE_FETCH_PVN;
3194 if (flags & ~(REFCOUNTED_HE_KEY_UTF8|REFCOUNTED_HE_EXISTS))
3195 Perl_croak(aTHX_ "panic: refcounted_he_fetch_pvn bad flags %"UVxf,
3199 if (flags & REFCOUNTED_HE_KEY_UTF8) {
3200 /* For searching purposes, canonicalise to Latin-1 where possible. */
3201 const char *keyend = keypv + keylen, *p;
3202 STRLEN nonascii_count = 0;
3203 for (p = keypv; p != keyend; p++) {
3204 if (! UTF8_IS_INVARIANT(*p)) {
3205 if (! UTF8_IS_NEXT_CHAR_DOWNGRADEABLE(p, keyend)) {
3206 goto canonicalised_key;
3212 if (nonascii_count) {
3214 const char *p = keypv, *keyend = keypv + keylen;
3215 keylen -= nonascii_count;
3216 Newx(q, keylen, char);
3219 for (; p != keyend; p++, q++) {
3221 if (UTF8_IS_INVARIANT(c)) {
3226 *q = (char) EIGHT_BIT_UTF8_TO_NATIVE(c, *p);
3230 flags &= ~REFCOUNTED_HE_KEY_UTF8;
3231 canonicalised_key: ;
3233 utf8_flag = (flags & REFCOUNTED_HE_KEY_UTF8) ? HVhek_UTF8 : 0;
3235 PERL_HASH(hash, keypv, keylen);
3237 for (; chain; chain = chain->refcounted_he_next) {
3240 hash == chain->refcounted_he_hash &&
3241 keylen == chain->refcounted_he_keylen &&
3242 memEQ(REF_HE_KEY(chain), keypv, keylen) &&
3243 utf8_flag == (chain->refcounted_he_data[0] & HVhek_UTF8)
3245 hash == HEK_HASH(chain->refcounted_he_hek) &&
3246 keylen == (STRLEN)HEK_LEN(chain->refcounted_he_hek) &&
3247 memEQ(HEK_KEY(chain->refcounted_he_hek), keypv, keylen) &&
3248 utf8_flag == (HEK_FLAGS(chain->refcounted_he_hek) & HVhek_UTF8)
3251 if (flags & REFCOUNTED_HE_EXISTS)
3252 return (chain->refcounted_he_data[0] & HVrhek_typemask)
3254 ? NULL : &PL_sv_yes;
3255 return sv_2mortal(refcounted_he_value(chain));
3259 return flags & REFCOUNTED_HE_EXISTS ? NULL : &PL_sv_placeholder;
3263 =for apidoc m|SV *|refcounted_he_fetch_pv|const struct refcounted_he *chain|const char *key|U32 hash|U32 flags
3265 Like L</refcounted_he_fetch_pvn>, but takes a nul-terminated string
3266 instead of a string/length pair.
3272 Perl_refcounted_he_fetch_pv(pTHX_ const struct refcounted_he *chain,
3273 const char *key, U32 hash, U32 flags)
3275 PERL_ARGS_ASSERT_REFCOUNTED_HE_FETCH_PV;
3276 return refcounted_he_fetch_pvn(chain, key, strlen(key), hash, flags);
3280 =for apidoc m|SV *|refcounted_he_fetch_sv|const struct refcounted_he *chain|SV *key|U32 hash|U32 flags
3282 Like L</refcounted_he_fetch_pvn>, but takes a Perl scalar instead of a
3289 Perl_refcounted_he_fetch_sv(pTHX_ const struct refcounted_he *chain,
3290 SV *key, U32 hash, U32 flags)
3294 PERL_ARGS_ASSERT_REFCOUNTED_HE_FETCH_SV;
3295 if (flags & REFCOUNTED_HE_KEY_UTF8)
3296 Perl_croak(aTHX_ "panic: refcounted_he_fetch_sv bad flags %"UVxf,
3298 keypv = SvPV_const(key, keylen);
3300 flags |= REFCOUNTED_HE_KEY_UTF8;
3301 if (!hash && SvIsCOW_shared_hash(key))
3302 hash = SvSHARED_HASH(key);
3303 return refcounted_he_fetch_pvn(chain, keypv, keylen, hash, flags);
3307 =for apidoc m|struct refcounted_he *|refcounted_he_new_pvn|struct refcounted_he *parent|const char *keypv|STRLEN keylen|U32 hash|SV *value|U32 flags
3309 Creates a new C<refcounted_he>. This consists of a single key/value
3310 pair and a reference to an existing C<refcounted_he> chain (which may
3311 be empty), and thus forms a longer chain. When using the longer chain,
3312 the new key/value pair takes precedence over any entry for the same key
3313 further along the chain.
3315 The new key is specified by C<keypv> and C<keylen>. If C<flags> has
3316 the C<REFCOUNTED_HE_KEY_UTF8> bit set, the key octets are interpreted
3317 as UTF-8, otherwise they are interpreted as Latin-1. C<hash> is
3318 a precomputed hash of the key string, or zero if it has not been
3321 C<value> is the scalar value to store for this key. C<value> is copied
3322 by this function, which thus does not take ownership of any reference
3323 to it, and later changes to the scalar will not be reflected in the
3324 value visible in the C<refcounted_he>. Complex types of scalar will not
3325 be stored with referential integrity, but will be coerced to strings.
3326 C<value> may be either null or C<&PL_sv_placeholder> to indicate that no
3327 value is to be associated with the key; this, as with any non-null value,
3328 takes precedence over the existence of a value for the key further along
3331 C<parent> points to the rest of the C<refcounted_he> chain to be
3332 attached to the new C<refcounted_he>. This function takes ownership
3333 of one reference to C<parent>, and returns one reference to the new
3339 struct refcounted_he *
3340 Perl_refcounted_he_new_pvn(pTHX_ struct refcounted_he *parent,
3341 const char *keypv, STRLEN keylen, U32 hash, SV *value, U32 flags)
3344 STRLEN value_len = 0;
3345 const char *value_p = NULL;
3349 STRLEN key_offset = 1;
3350 struct refcounted_he *he;
3351 PERL_ARGS_ASSERT_REFCOUNTED_HE_NEW_PVN;
3353 if (!value || value == &PL_sv_placeholder) {
3354 value_type = HVrhek_delete;
3355 } else if (SvPOK(value)) {
3356 value_type = HVrhek_PV;
3357 } else if (SvIOK(value)) {
3358 value_type = SvUOK((const SV *)value) ? HVrhek_UV : HVrhek_IV;
3359 } else if (!SvOK(value)) {
3360 value_type = HVrhek_undef;
3362 value_type = HVrhek_PV;
3364 is_pv = value_type == HVrhek_PV;
3366 /* Do it this way so that the SvUTF8() test is after the SvPV, in case
3367 the value is overloaded, and doesn't yet have the UTF-8flag set. */
3368 value_p = SvPV_const(value, value_len);
3370 value_type = HVrhek_PV_UTF8;
3371 key_offset = value_len + 2;
3373 hekflags = value_type;
3375 if (flags & REFCOUNTED_HE_KEY_UTF8) {
3376 /* Canonicalise to Latin-1 where possible. */
3377 const char *keyend = keypv + keylen, *p;
3378 STRLEN nonascii_count = 0;
3379 for (p = keypv; p != keyend; p++) {
3380 if (! UTF8_IS_INVARIANT(*p)) {
3381 if (! UTF8_IS_NEXT_CHAR_DOWNGRADEABLE(p, keyend)) {
3382 goto canonicalised_key;
3388 if (nonascii_count) {
3390 const char *p = keypv, *keyend = keypv + keylen;
3391 keylen -= nonascii_count;
3392 Newx(q, keylen, char);
3395 for (; p != keyend; p++, q++) {
3397 if (UTF8_IS_INVARIANT(c)) {
3402 *q = (char) EIGHT_BIT_UTF8_TO_NATIVE(c, *p);
3406 flags &= ~REFCOUNTED_HE_KEY_UTF8;
3407 canonicalised_key: ;
3409 if (flags & REFCOUNTED_HE_KEY_UTF8)
3410 hekflags |= HVhek_UTF8;
3412 PERL_HASH(hash, keypv, keylen);
3415 he = (struct refcounted_he*)
3416 PerlMemShared_malloc(sizeof(struct refcounted_he) - 1
3420 he = (struct refcounted_he*)
3421 PerlMemShared_malloc(sizeof(struct refcounted_he) - 1
3425 he->refcounted_he_next = parent;
3428 Copy(value_p, he->refcounted_he_data + 1, value_len + 1, char);
3429 he->refcounted_he_val.refcounted_he_u_len = value_len;
3430 } else if (value_type == HVrhek_IV) {
3431 he->refcounted_he_val.refcounted_he_u_iv = SvIVX(value);
3432 } else if (value_type == HVrhek_UV) {
3433 he->refcounted_he_val.refcounted_he_u_uv = SvUVX(value);
3437 he->refcounted_he_hash = hash;
3438 he->refcounted_he_keylen = keylen;
3439 Copy(keypv, he->refcounted_he_data + key_offset, keylen, char);
3441 he->refcounted_he_hek = share_hek_flags(keypv, keylen, hash, hekflags);
3444 he->refcounted_he_data[0] = hekflags;
3445 he->refcounted_he_refcnt = 1;
3451 =for apidoc m|struct refcounted_he *|refcounted_he_new_pv|struct refcounted_he *parent|const char *key|U32 hash|SV *value|U32 flags
3453 Like L</refcounted_he_new_pvn>, but takes a nul-terminated string instead
3454 of a string/length pair.
3459 struct refcounted_he *
3460 Perl_refcounted_he_new_pv(pTHX_ struct refcounted_he *parent,
3461 const char *key, U32 hash, SV *value, U32 flags)
3463 PERL_ARGS_ASSERT_REFCOUNTED_HE_NEW_PV;
3464 return refcounted_he_new_pvn(parent, key, strlen(key), hash, value, flags);
3468 =for apidoc m|struct refcounted_he *|refcounted_he_new_sv|struct refcounted_he *parent|SV *key|U32 hash|SV *value|U32 flags
3470 Like L</refcounted_he_new_pvn>, but takes a Perl scalar instead of a
3476 struct refcounted_he *
3477 Perl_refcounted_he_new_sv(pTHX_ struct refcounted_he *parent,
3478 SV *key, U32 hash, SV *value, U32 flags)
3482 PERL_ARGS_ASSERT_REFCOUNTED_HE_NEW_SV;
3483 if (flags & REFCOUNTED_HE_KEY_UTF8)
3484 Perl_croak(aTHX_ "panic: refcounted_he_new_sv bad flags %"UVxf,
3486 keypv = SvPV_const(key, keylen);
3488 flags |= REFCOUNTED_HE_KEY_UTF8;
3489 if (!hash && SvIsCOW_shared_hash(key))
3490 hash = SvSHARED_HASH(key);
3491 return refcounted_he_new_pvn(parent, keypv, keylen, hash, value, flags);
3495 =for apidoc m|void|refcounted_he_free|struct refcounted_he *he
3497 Decrements the reference count of a C<refcounted_he> by one. If the
3498 reference count reaches zero the structure's memory is freed, which
3499 (recursively) causes a reduction of its parent C<refcounted_he>'s
3500 reference count. It is safe to pass a null pointer to this function:
3501 no action occurs in this case.
3507 Perl_refcounted_he_free(pTHX_ struct refcounted_he *he) {
3511 PERL_UNUSED_CONTEXT;
3514 struct refcounted_he *copy;
3518 new_count = --he->refcounted_he_refcnt;
3519 HINTS_REFCNT_UNLOCK;
3525 #ifndef USE_ITHREADS
3526 unshare_hek_or_pvn (he->refcounted_he_hek, 0, 0, 0);
3529 he = he->refcounted_he_next;
3530 PerlMemShared_free(copy);
3535 =for apidoc m|struct refcounted_he *|refcounted_he_inc|struct refcounted_he *he
3537 Increment the reference count of a C<refcounted_he>. The pointer to the
3538 C<refcounted_he> is also returned. It is safe to pass a null pointer
3539 to this function: no action occurs and a null pointer is returned.
3544 struct refcounted_he *
3545 Perl_refcounted_he_inc(pTHX_ struct refcounted_he *he)
3550 PERL_UNUSED_CONTEXT;
3553 he->refcounted_he_refcnt++;
3554 HINTS_REFCNT_UNLOCK;
3560 =for apidoc cop_fetch_label
3562 Returns the label attached to a cop.
3563 The flags pointer may be set to C<SVf_UTF8> or 0.
3568 /* pp_entereval is aware that labels are stored with a key ':' at the top of
3571 Perl_cop_fetch_label(pTHX_ COP *const cop, STRLEN *len, U32 *flags) {
3572 struct refcounted_he *const chain = cop->cop_hints_hash;
3574 PERL_ARGS_ASSERT_COP_FETCH_LABEL;
3575 PERL_UNUSED_CONTEXT;
3580 if (chain->refcounted_he_keylen != 1)
3582 if (*REF_HE_KEY(chain) != ':')
3585 if ((STRLEN)HEK_LEN(chain->refcounted_he_hek) != 1)
3587 if (*HEK_KEY(chain->refcounted_he_hek) != ':')
3590 /* Stop anyone trying to really mess us up by adding their own value for
3592 if ((chain->refcounted_he_data[0] & HVrhek_typemask) != HVrhek_PV
3593 && (chain->refcounted_he_data[0] & HVrhek_typemask) != HVrhek_PV_UTF8)
3597 *len = chain->refcounted_he_val.refcounted_he_u_len;
3599 *flags = ((chain->refcounted_he_data[0] & HVrhek_typemask)
3600 == HVrhek_PV_UTF8) ? SVf_UTF8 : 0;
3602 return chain->refcounted_he_data + 1;
3606 =for apidoc cop_store_label
3608 Save a label into a C<cop_hints_hash>.
3609 You need to set flags to C<SVf_UTF8>
3616 Perl_cop_store_label(pTHX_ COP *const cop, const char *label, STRLEN len,
3620 PERL_ARGS_ASSERT_COP_STORE_LABEL;
3622 if (flags & ~(SVf_UTF8))
3623 Perl_croak(aTHX_ "panic: cop_store_label illegal flag bits 0x%" UVxf,
3625 labelsv = newSVpvn_flags(label, len, SVs_TEMP);
3626 if (flags & SVf_UTF8)
3629 = refcounted_he_new_pvs(cop->cop_hints_hash, ":", labelsv, 0);
3633 =for apidoc hv_assert
3635 Check that a hash is in an internally consistent state.
3643 Perl_hv_assert(pTHX_ HV *hv)
3648 int placeholders = 0;
3651 const I32 riter = HvRITER_get(hv);
3652 HE *eiter = HvEITER_get(hv);
3654 PERL_ARGS_ASSERT_HV_ASSERT;
3656 (void)hv_iterinit(hv);
3658 while ((entry = hv_iternext_flags(hv, HV_ITERNEXT_WANTPLACEHOLDERS))) {
3659 /* sanity check the values */
3660 if (HeVAL(entry) == &PL_sv_placeholder)
3664 /* sanity check the keys */
3665 if (HeSVKEY(entry)) {
3666 NOOP; /* Don't know what to check on SV keys. */
3667 } else if (HeKUTF8(entry)) {
3669 if (HeKWASUTF8(entry)) {
3670 PerlIO_printf(Perl_debug_log,
3671 "hash key has both WASUTF8 and UTF8: '%.*s'\n",
3672 (int) HeKLEN(entry), HeKEY(entry));
3675 } else if (HeKWASUTF8(entry))
3678 if (!SvTIED_mg((const SV *)hv, PERL_MAGIC_tied)) {
3679 static const char bad_count[] = "Count %d %s(s), but hash reports %d\n";
3680 const int nhashkeys = HvUSEDKEYS(hv);
3681 const int nhashplaceholders = HvPLACEHOLDERS_get(hv);
3683 if (nhashkeys != real) {
3684 PerlIO_printf(Perl_debug_log, bad_count, real, "keys", nhashkeys );
3687 if (nhashplaceholders != placeholders) {
3688 PerlIO_printf(Perl_debug_log, bad_count, placeholders, "placeholder", nhashplaceholders );
3692 if (withflags && ! HvHASKFLAGS(hv)) {
3693 PerlIO_printf(Perl_debug_log,
3694 "Hash has HASKFLAGS off but I count %d key(s) with flags\n",
3699 sv_dump(MUTABLE_SV(hv));
3701 HvRITER_set(hv, riter); /* Restore hash iterator state */
3702 HvEITER_set(hv, eiter);
3708 * ex: set ts=8 sts=4 sw=4 et: