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
22 A HV structure represents a Perl hash. It consists mainly of an array
23 of pointers, each of which points to a linked list of HE structures. The
24 array is indexed by the hash function of the key, so each linked list
25 represents all the hash entries with the same hash value. Each HE contains
26 a pointer to the actual value, plus a pointer to a HEK structure which
27 holds the key and hash value.
35 #define PERL_HASH_INTERNAL_ACCESS
38 #define HV_MAX_LENGTH_BEFORE_SPLIT 14
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)
55 void ** const root = &PL_body_roots[HE_SVSLOT];
58 Perl_more_bodies(aTHX_ HE_SVSLOT, sizeof(HE), PERL_ARENA_SIZE);
65 #define new_HE() new_he()
68 HeNEXT(p) = (HE*)(PL_body_roots[HE_SVSLOT]); \
69 PL_body_roots[HE_SVSLOT] = p; \
77 S_save_hek_flags(const char *str, I32 len, U32 hash, int flags)
79 const int flags_masked = flags & HVhek_MASK;
83 PERL_ARGS_ASSERT_SAVE_HEK_FLAGS;
85 Newx(k, HEK_BASESIZE + len + 2, char);
87 Copy(str, HEK_KEY(hek), len, char);
88 HEK_KEY(hek)[len] = 0;
91 HEK_FLAGS(hek) = (unsigned char)flags_masked | HVhek_UNSHARED;
93 if (flags & HVhek_FREEKEY)
98 /* free the pool of temporary HE/HEK pairs returned by hv_fetch_ent
102 Perl_free_tied_hv_pool(pTHX)
105 HE *he = PL_hv_fetch_ent_mh;
108 Safefree(HeKEY_hek(he));
112 PL_hv_fetch_ent_mh = NULL;
115 #if defined(USE_ITHREADS)
117 Perl_hek_dup(pTHX_ HEK *source, CLONE_PARAMS* param)
121 PERL_ARGS_ASSERT_HEK_DUP;
122 PERL_UNUSED_ARG(param);
127 shared = (HEK*)ptr_table_fetch(PL_ptr_table, source);
129 /* We already shared this hash key. */
130 (void)share_hek_hek(shared);
134 = share_hek_flags(HEK_KEY(source), HEK_LEN(source),
135 HEK_HASH(source), HEK_FLAGS(source));
136 ptr_table_store(PL_ptr_table, source, shared);
142 Perl_he_dup(pTHX_ const HE *e, bool shared, CLONE_PARAMS* param)
146 PERL_ARGS_ASSERT_HE_DUP;
150 /* look for it in the table first */
151 ret = (HE*)ptr_table_fetch(PL_ptr_table, e);
155 /* create anew and remember what it is */
157 ptr_table_store(PL_ptr_table, e, ret);
159 HeNEXT(ret) = he_dup(HeNEXT(e),shared, param);
160 if (HeKLEN(e) == HEf_SVKEY) {
162 Newx(k, HEK_BASESIZE + sizeof(const SV *), char);
163 HeKEY_hek(ret) = (HEK*)k;
164 HeKEY_sv(ret) = sv_dup_inc(HeKEY_sv(e), param);
167 /* This is hek_dup inlined, which seems to be important for speed
169 HEK * const source = HeKEY_hek(e);
170 HEK *shared = (HEK*)ptr_table_fetch(PL_ptr_table, source);
173 /* We already shared this hash key. */
174 (void)share_hek_hek(shared);
178 = share_hek_flags(HEK_KEY(source), HEK_LEN(source),
179 HEK_HASH(source), HEK_FLAGS(source));
180 ptr_table_store(PL_ptr_table, source, shared);
182 HeKEY_hek(ret) = shared;
185 HeKEY_hek(ret) = save_hek_flags(HeKEY(e), HeKLEN(e), HeHASH(e),
187 HeVAL(ret) = sv_dup_inc(HeVAL(e), param);
190 #endif /* USE_ITHREADS */
193 S_hv_notallowed(pTHX_ int flags, const char *key, I32 klen,
196 SV * const sv = sv_newmortal();
198 PERL_ARGS_ASSERT_HV_NOTALLOWED;
200 if (!(flags & HVhek_FREEKEY)) {
201 sv_setpvn(sv, key, klen);
204 /* Need to free saved eventually assign to mortal SV */
205 /* XXX is this line an error ???: SV *sv = sv_newmortal(); */
206 sv_usepvn(sv, (char *) key, klen);
208 if (flags & HVhek_UTF8) {
211 Perl_croak(aTHX_ msg, SVfARG(sv));
214 /* (klen == HEf_SVKEY) is special for MAGICAL hv entries, meaning key slot
220 Stores an SV in a hash. The hash key is specified as C<key> and C<klen> is
221 the length of the key. The C<hash> parameter is the precomputed hash
222 value; if it is zero then Perl will compute it. The return value will be
223 NULL if the operation failed or if the value did not need to be actually
224 stored within the hash (as in the case of tied hashes). Otherwise it can
225 be dereferenced to get the original C<SV*>. Note that the caller is
226 responsible for suitably incrementing the reference count of C<val> before
227 the call, and decrementing it if the function returned NULL. Effectively
228 a successful hv_store takes ownership of one reference to C<val>. This is
229 usually what you want; a newly created SV has a reference count of one, so
230 if all your code does is create SVs then store them in a hash, hv_store
231 will own the only reference to the new SV, and your code doesn't need to do
232 anything further to tidy up. hv_store is not implemented as a call to
233 hv_store_ent, and does not create a temporary SV for the key, so if your
234 key data is not already in SV form then use hv_store in preference to
237 See L<perlguts/"Understanding the Magic of Tied Hashes and Arrays"> for more
238 information on how to use this function on tied hashes.
240 =for apidoc hv_store_ent
242 Stores C<val> in a hash. The hash key is specified as C<key>. The C<hash>
243 parameter is the precomputed hash value; if it is zero then Perl will
244 compute it. The return value is the new hash entry so created. It will be
245 NULL if the operation failed or if the value did not need to be actually
246 stored within the hash (as in the case of tied hashes). Otherwise the
247 contents of the return value can be accessed using the C<He?> macros
248 described here. Note that the caller is responsible for suitably
249 incrementing the reference count of C<val> before the call, and
250 decrementing it if the function returned NULL. Effectively a successful
251 hv_store_ent takes ownership of one reference to C<val>. This is
252 usually what you want; a newly created SV has a reference count of one, so
253 if all your code does is create SVs then store them in a hash, hv_store
254 will own the only reference to the new SV, and your code doesn't need to do
255 anything further to tidy up. Note that hv_store_ent only reads the C<key>;
256 unlike C<val> it does not take ownership of it, so maintaining the correct
257 reference count on C<key> is entirely the caller's responsibility. hv_store
258 is not implemented as a call to hv_store_ent, and does not create a temporary
259 SV for the key, so if your key data is not already in SV form then use
260 hv_store in preference to hv_store_ent.
262 See L<perlguts/"Understanding the Magic of Tied Hashes and Arrays"> for more
263 information on how to use this function on tied hashes.
265 =for apidoc hv_exists
267 Returns a boolean indicating whether the specified hash key exists. The
268 C<klen> is the length of the key.
272 Returns the SV which corresponds to the specified key in the hash. The
273 C<klen> is the length of the key. If C<lval> is set then the fetch will be
274 part of a store. Check that the return value is non-null before
275 dereferencing it to an C<SV*>.
277 See L<perlguts/"Understanding the Magic of Tied Hashes and Arrays"> for more
278 information on how to use this function on tied hashes.
280 =for apidoc hv_exists_ent
282 Returns a boolean indicating whether the specified hash key exists. C<hash>
283 can be a valid precomputed hash value, or 0 to ask for it to be
289 /* returns an HE * structure with the all fields set */
290 /* note that hent_val will be a mortal sv for MAGICAL hashes */
292 =for apidoc hv_fetch_ent
294 Returns the hash entry which corresponds to the specified key in the hash.
295 C<hash> must be a valid precomputed hash number for the given C<key>, or 0
296 if you want the function to compute it. IF C<lval> is set then the fetch
297 will be part of a store. Make sure the return value is non-null before
298 accessing it. The return value when C<hv> is a tied hash is a pointer to a
299 static location, so be sure to make a copy of the structure if you need to
302 See L<perlguts/"Understanding the Magic of Tied Hashes and Arrays"> for more
303 information on how to use this function on tied hashes.
308 /* Common code for hv_delete()/hv_exists()/hv_fetch()/hv_store() */
310 Perl_hv_common_key_len(pTHX_ HV *hv, const char *key, I32 klen_i32,
311 const int action, SV *val, const U32 hash)
316 PERL_ARGS_ASSERT_HV_COMMON_KEY_LEN;
325 return hv_common(hv, NULL, key, klen, flags, action, val, hash);
329 Perl_hv_common(pTHX_ HV *hv, SV *keysv, const char *key, STRLEN klen,
330 int flags, int action, SV *val, register U32 hash)
339 const int return_svp = action & HV_FETCH_JUST_SV;
343 if (SvTYPE(hv) == SVTYPEMASK)
346 assert(SvTYPE(hv) == SVt_PVHV);
348 if (SvSMAGICAL(hv) && SvGMAGICAL(hv) && !(action & HV_DISABLE_UVAR_XKEY)) {
350 if ((mg = mg_find((const SV *)hv, PERL_MAGIC_uvar))) {
351 struct ufuncs * const uf = (struct ufuncs *)mg->mg_ptr;
352 if (uf->uf_set == NULL) {
353 SV* obj = mg->mg_obj;
356 keysv = newSVpvn_flags(key, klen, SVs_TEMP |
357 ((flags & HVhek_UTF8)
361 mg->mg_obj = keysv; /* pass key */
362 uf->uf_index = action; /* pass action */
363 magic_getuvar(MUTABLE_SV(hv), mg);
364 keysv = mg->mg_obj; /* may have changed */
367 /* If the key may have changed, then we need to invalidate
368 any passed-in computed hash value. */
374 if (flags & HVhek_FREEKEY)
376 key = SvPV_const(keysv, klen);
377 is_utf8 = (SvUTF8(keysv) != 0);
378 if (SvIsCOW_shared_hash(keysv)) {
379 flags = HVhek_KEYCANONICAL | (is_utf8 ? HVhek_UTF8 : 0);
384 is_utf8 = ((flags & HVhek_UTF8) ? TRUE : FALSE);
387 if (action & HV_DELETE) {
388 return (void *) hv_delete_common(hv, keysv, key, klen,
389 flags | (is_utf8 ? HVhek_UTF8 : 0),
393 xhv = (XPVHV*)SvANY(hv);
395 if (SvRMAGICAL(hv) && !(action & (HV_FETCH_ISSTORE|HV_FETCH_ISEXISTS))) {
396 if (mg_find((const SV *)hv, PERL_MAGIC_tied)
397 || SvGMAGICAL((const SV *)hv))
399 /* FIXME should be able to skimp on the HE/HEK here when
400 HV_FETCH_JUST_SV is true. */
402 keysv = newSVpvn_utf8(key, klen, is_utf8);
404 keysv = newSVsv(keysv);
407 mg_copy(MUTABLE_SV(hv), sv, (char *)keysv, HEf_SVKEY);
409 /* grab a fake HE/HEK pair from the pool or make a new one */
410 entry = PL_hv_fetch_ent_mh;
412 PL_hv_fetch_ent_mh = HeNEXT(entry);
416 Newx(k, HEK_BASESIZE + sizeof(const SV *), char);
417 HeKEY_hek(entry) = (HEK*)k;
419 HeNEXT(entry) = NULL;
420 HeSVKEY_set(entry, keysv);
422 sv_upgrade(sv, SVt_PVLV);
424 /* so we can free entry when freeing sv */
425 LvTARG(sv) = MUTABLE_SV(entry);
427 /* XXX remove at some point? */
428 if (flags & HVhek_FREEKEY)
432 return entry ? (void *) &HeVAL(entry) : NULL;
434 return (void *) entry;
436 #ifdef ENV_IS_CASELESS
437 else if (mg_find((const SV *)hv, PERL_MAGIC_env)) {
439 for (i = 0; i < klen; ++i)
440 if (isLOWER(key[i])) {
441 /* Would be nice if we had a routine to do the
442 copy and upercase in a single pass through. */
443 const char * const nkey = strupr(savepvn(key,klen));
444 /* Note that this fetch is for nkey (the uppercased
445 key) whereas the store is for key (the original) */
446 void *result = hv_common(hv, NULL, nkey, klen,
447 HVhek_FREEKEY, /* free nkey */
448 0 /* non-LVAL fetch */
449 | HV_DISABLE_UVAR_XKEY
452 0 /* compute hash */);
453 if (!result && (action & HV_FETCH_LVALUE)) {
454 /* This call will free key if necessary.
455 Do it this way to encourage compiler to tail
457 result = hv_common(hv, keysv, key, klen, flags,
459 | HV_DISABLE_UVAR_XKEY
463 if (flags & HVhek_FREEKEY)
471 else if (SvRMAGICAL(hv) && (action & HV_FETCH_ISEXISTS)) {
472 if (mg_find((const SV *)hv, PERL_MAGIC_tied)
473 || SvGMAGICAL((const SV *)hv)) {
474 /* I don't understand why hv_exists_ent has svret and sv,
475 whereas hv_exists only had one. */
476 SV * const svret = sv_newmortal();
479 if (keysv || is_utf8) {
481 keysv = newSVpvn_utf8(key, klen, TRUE);
483 keysv = newSVsv(keysv);
485 mg_copy(MUTABLE_SV(hv), sv, (char *)sv_2mortal(keysv), HEf_SVKEY);
487 mg_copy(MUTABLE_SV(hv), sv, key, klen);
489 if (flags & HVhek_FREEKEY)
491 magic_existspack(svret, mg_find(sv, PERL_MAGIC_tiedelem));
492 /* This cast somewhat evil, but I'm merely using NULL/
493 not NULL to return the boolean exists.
494 And I know hv is not NULL. */
495 return SvTRUE(svret) ? (void *)hv : NULL;
497 #ifdef ENV_IS_CASELESS
498 else if (mg_find((const SV *)hv, PERL_MAGIC_env)) {
499 /* XXX This code isn't UTF8 clean. */
500 char * const keysave = (char * const)key;
501 /* Will need to free this, so set FREEKEY flag. */
502 key = savepvn(key,klen);
503 key = (const char*)strupr((char*)key);
508 if (flags & HVhek_FREEKEY) {
511 flags |= HVhek_FREEKEY;
515 else if (action & HV_FETCH_ISSTORE) {
518 hv_magic_check (hv, &needs_copy, &needs_store);
520 const bool save_taint = PL_tainted;
521 if (keysv || is_utf8) {
523 keysv = newSVpvn_utf8(key, klen, TRUE);
526 PL_tainted = SvTAINTED(keysv);
527 keysv = sv_2mortal(newSVsv(keysv));
528 mg_copy(MUTABLE_SV(hv), val, (char*)keysv, HEf_SVKEY);
530 mg_copy(MUTABLE_SV(hv), val, key, klen);
533 TAINT_IF(save_taint);
535 if (flags & HVhek_FREEKEY)
539 #ifdef ENV_IS_CASELESS
540 else if (mg_find((const SV *)hv, PERL_MAGIC_env)) {
541 /* XXX This code isn't UTF8 clean. */
542 const char *keysave = key;
543 /* Will need to free this, so set FREEKEY flag. */
544 key = savepvn(key,klen);
545 key = (const char*)strupr((char*)key);
550 if (flags & HVhek_FREEKEY) {
553 flags |= HVhek_FREEKEY;
561 if ((action & (HV_FETCH_LVALUE | HV_FETCH_ISSTORE))
562 #ifdef DYNAMIC_ENV_FETCH /* if it's an %ENV lookup, we may get it on the fly */
563 || (SvRMAGICAL((const SV *)hv)
564 && mg_find((const SV *)hv, PERL_MAGIC_env))
569 PERL_HV_ARRAY_ALLOC_BYTES(xhv->xhv_max+1 /* HvMAX(hv)+1 */),
571 HvARRAY(hv) = (HE**)array;
573 #ifdef DYNAMIC_ENV_FETCH
574 else if (action & HV_FETCH_ISEXISTS) {
575 /* for an %ENV exists, if we do an insert it's by a recursive
576 store call, so avoid creating HvARRAY(hv) right now. */
580 /* XXX remove at some point? */
581 if (flags & HVhek_FREEKEY)
588 if (is_utf8 & !(flags & HVhek_KEYCANONICAL)) {
589 char * const keysave = (char *)key;
590 key = (char*)bytes_from_utf8((U8*)key, &klen, &is_utf8);
594 flags &= ~HVhek_UTF8;
595 if (key != keysave) {
596 if (flags & HVhek_FREEKEY)
598 flags |= HVhek_WASUTF8 | HVhek_FREEKEY;
599 /* If the caller calculated a hash, it was on the sequence of
600 octets that are the UTF-8 form. We've now changed the sequence
601 of octets stored to that of the equivalent byte representation,
602 so the hash we need is different. */
608 PERL_HASH_INTERNAL(hash, key, klen);
609 /* We don't have a pointer to the hv, so we have to replicate the
610 flag into every HEK, so that hv_iterkeysv can see it. */
611 /* And yes, you do need this even though you are not "storing" because
612 you can flip the flags below if doing an lval lookup. (And that
613 was put in to give the semantics Andreas was expecting.) */
614 flags |= HVhek_REHASH;
616 if (keysv && (SvIsCOW_shared_hash(keysv))) {
617 hash = SvSHARED_HASH(keysv);
619 PERL_HASH(hash, key, klen);
623 masked_flags = (flags & HVhek_MASK);
625 #ifdef DYNAMIC_ENV_FETCH
626 if (!HvARRAY(hv)) entry = NULL;
630 entry = (HvARRAY(hv))[hash & (I32) HvMAX(hv)];
632 for (; entry; entry = HeNEXT(entry)) {
633 if (HeHASH(entry) != hash) /* strings can't be equal */
635 if (HeKLEN(entry) != (I32)klen)
637 if (HeKEY(entry) != key && memNE(HeKEY(entry),key,klen)) /* is this it? */
639 if ((HeKFLAGS(entry) ^ masked_flags) & HVhek_UTF8)
642 if (action & (HV_FETCH_LVALUE|HV_FETCH_ISSTORE)) {
643 if (HeKFLAGS(entry) != masked_flags) {
644 /* We match if HVhek_UTF8 bit in our flags and hash key's
645 match. But if entry was set previously with HVhek_WASUTF8
646 and key now doesn't (or vice versa) then we should change
647 the key's flag, as this is assignment. */
648 if (HvSHAREKEYS(hv)) {
649 /* Need to swap the key we have for a key with the flags we
650 need. As keys are shared we can't just write to the
651 flag, so we share the new one, unshare the old one. */
652 HEK * const new_hek = share_hek_flags(key, klen, hash,
654 unshare_hek (HeKEY_hek(entry));
655 HeKEY_hek(entry) = new_hek;
657 else if (hv == PL_strtab) {
658 /* PL_strtab is usually the only hash without HvSHAREKEYS,
659 so putting this test here is cheap */
660 if (flags & HVhek_FREEKEY)
662 Perl_croak(aTHX_ S_strtab_error,
663 action & HV_FETCH_LVALUE ? "fetch" : "store");
666 HeKFLAGS(entry) = masked_flags;
667 if (masked_flags & HVhek_ENABLEHVKFLAGS)
670 if (HeVAL(entry) == &PL_sv_placeholder) {
671 /* yes, can store into placeholder slot */
672 if (action & HV_FETCH_LVALUE) {
674 /* This preserves behaviour with the old hv_fetch
675 implementation which at this point would bail out
676 with a break; (at "if we find a placeholder, we
677 pretend we haven't found anything")
679 That break mean that if a placeholder were found, it
680 caused a call into hv_store, which in turn would
681 check magic, and if there is no magic end up pretty
682 much back at this point (in hv_store's code). */
685 /* LVAL fetch which actaully needs a store. */
687 HvPLACEHOLDERS(hv)--;
690 if (val != &PL_sv_placeholder)
691 HvPLACEHOLDERS(hv)--;
694 } else if (action & HV_FETCH_ISSTORE) {
695 SvREFCNT_dec(HeVAL(entry));
698 } else if (HeVAL(entry) == &PL_sv_placeholder) {
699 /* if we find a placeholder, we pretend we haven't found
703 if (flags & HVhek_FREEKEY)
706 return entry ? (void *) &HeVAL(entry) : NULL;
710 #ifdef DYNAMIC_ENV_FETCH /* %ENV lookup? If so, try to fetch the value now */
711 if (!(action & HV_FETCH_ISSTORE)
712 && SvRMAGICAL((const SV *)hv)
713 && mg_find((const SV *)hv, PERL_MAGIC_env)) {
715 const char * const env = PerlEnv_ENVgetenv_len(key,&len);
717 sv = newSVpvn(env,len);
719 return hv_common(hv, keysv, key, klen, flags,
720 HV_FETCH_ISSTORE|HV_DISABLE_UVAR_XKEY|return_svp,
726 if (!entry && SvREADONLY(hv) && !(action & HV_FETCH_ISEXISTS)) {
727 hv_notallowed(flags, key, klen,
728 "Attempt to access disallowed key '%"SVf"' in"
729 " a restricted hash");
731 if (!(action & (HV_FETCH_LVALUE|HV_FETCH_ISSTORE))) {
732 /* Not doing some form of store, so return failure. */
733 if (flags & HVhek_FREEKEY)
737 if (action & HV_FETCH_LVALUE) {
738 val = action & HV_FETCH_EMPTY_HE ? NULL : newSV(0);
740 /* At this point the old hv_fetch code would call to hv_store,
741 which in turn might do some tied magic. So we need to make that
742 magic check happen. */
743 /* gonna assign to this, so it better be there */
744 /* If a fetch-as-store fails on the fetch, then the action is to
745 recurse once into "hv_store". If we didn't do this, then that
746 recursive call would call the key conversion routine again.
747 However, as we replace the original key with the converted
748 key, this would result in a double conversion, which would show
749 up as a bug if the conversion routine is not idempotent. */
750 return hv_common(hv, keysv, key, klen, flags,
751 HV_FETCH_ISSTORE|HV_DISABLE_UVAR_XKEY|return_svp,
753 /* XXX Surely that could leak if the fetch-was-store fails?
754 Just like the hv_fetch. */
758 /* Welcome to hv_store... */
761 /* Not sure if we can get here. I think the only case of oentry being
762 NULL is for %ENV with dynamic env fetch. But that should disappear
763 with magic in the previous code. */
766 PERL_HV_ARRAY_ALLOC_BYTES(xhv->xhv_max+1 /* HvMAX(hv)+1 */),
768 HvARRAY(hv) = (HE**)array;
771 oentry = &(HvARRAY(hv))[hash & (I32) xhv->xhv_max];
774 /* share_hek_flags will do the free for us. This might be considered
777 HeKEY_hek(entry) = share_hek_flags(key, klen, hash, flags);
778 else if (hv == PL_strtab) {
779 /* PL_strtab is usually the only hash without HvSHAREKEYS, so putting
780 this test here is cheap */
781 if (flags & HVhek_FREEKEY)
783 Perl_croak(aTHX_ S_strtab_error,
784 action & HV_FETCH_LVALUE ? "fetch" : "store");
786 else /* gotta do the real thing */
787 HeKEY_hek(entry) = save_hek_flags(key, klen, hash, flags);
789 HeNEXT(entry) = *oentry;
792 if (val == &PL_sv_placeholder)
793 HvPLACEHOLDERS(hv)++;
794 if (masked_flags & HVhek_ENABLEHVKFLAGS)
798 const HE *counter = HeNEXT(entry);
800 xhv->xhv_keys++; /* HvTOTALKEYS(hv)++ */
801 if (!counter) { /* initial entry? */
802 } else if (xhv->xhv_keys > xhv->xhv_max) {
804 } else if(!HvREHASH(hv)) {
807 while ((counter = HeNEXT(counter)))
810 if (n_links > HV_MAX_LENGTH_BEFORE_SPLIT) {
811 /* Use only the old HvKEYS(hv) > HvMAX(hv) condition to limit
812 bucket splits on a rehashed hash, as we're not going to
813 split it again, and if someone is lucky (evil) enough to
814 get all the keys in one list they could exhaust our memory
815 as we repeatedly double the number of buckets on every
816 entry. Linear search feels a less worse thing to do. */
823 return entry ? (void *) &HeVAL(entry) : NULL;
825 return (void *) entry;
829 S_hv_magic_check(HV *hv, bool *needs_copy, bool *needs_store)
831 const MAGIC *mg = SvMAGIC(hv);
833 PERL_ARGS_ASSERT_HV_MAGIC_CHECK;
838 if (isUPPER(mg->mg_type)) {
840 if (mg->mg_type == PERL_MAGIC_tied) {
841 *needs_store = FALSE;
842 return; /* We've set all there is to set. */
845 mg = mg->mg_moremagic;
850 =for apidoc hv_scalar
852 Evaluates the hash in scalar context and returns the result. Handles magic when the hash is tied.
858 Perl_hv_scalar(pTHX_ HV *hv)
862 PERL_ARGS_ASSERT_HV_SCALAR;
864 if (SvRMAGICAL(hv)) {
865 MAGIC * const mg = mg_find((const SV *)hv, PERL_MAGIC_tied);
867 return magic_scalarpack(hv, mg);
871 if (HvTOTALKEYS((const HV *)hv))
872 Perl_sv_setpvf(aTHX_ sv, "%ld/%ld",
873 (long)HvFILL(hv), (long)HvMAX(hv) + 1);
881 =for apidoc hv_delete
883 Deletes a key/value pair in the hash. The value's SV is removed from the
884 hash, made mortal, and returned to the caller. The C<klen> is the length of
885 the key. The C<flags> value will normally be zero; if set to G_DISCARD then
886 NULL will be returned. NULL will also be returned if the key is not found.
888 =for apidoc hv_delete_ent
890 Deletes a key/value pair in the hash. The value SV is removed from the hash,
891 made mortal, and returned to the caller. The C<flags> value will normally be
892 zero; if set to G_DISCARD then NULL will be returned. NULL will also be
893 returned if the key is not found. C<hash> can be a valid precomputed hash
894 value, or 0 to ask for it to be computed.
900 S_hv_delete_common(pTHX_ HV *hv, SV *keysv, const char *key, STRLEN klen,
901 int k_flags, I32 d_flags, U32 hash)
906 register HE **oentry;
907 HE *const *first_entry;
908 bool is_utf8 = (k_flags & HVhek_UTF8) ? TRUE : FALSE;
911 if (SvRMAGICAL(hv)) {
914 hv_magic_check (hv, &needs_copy, &needs_store);
918 entry = (HE *) hv_common(hv, keysv, key, klen,
919 k_flags & ~HVhek_FREEKEY,
920 HV_FETCH_LVALUE|HV_DISABLE_UVAR_XKEY,
922 sv = entry ? HeVAL(entry) : NULL;
928 if (mg_find(sv, PERL_MAGIC_tiedelem)) {
929 /* No longer an element */
930 sv_unmagic(sv, PERL_MAGIC_tiedelem);
933 return NULL; /* element cannot be deleted */
935 #ifdef ENV_IS_CASELESS
936 else if (mg_find((const SV *)hv, PERL_MAGIC_env)) {
937 /* XXX This code isn't UTF8 clean. */
938 keysv = newSVpvn_flags(key, klen, SVs_TEMP);
939 if (k_flags & HVhek_FREEKEY) {
942 key = strupr(SvPVX(keysv));
951 xhv = (XPVHV*)SvANY(hv);
956 const char * const keysave = key;
957 key = (char*)bytes_from_utf8((U8*)key, &klen, &is_utf8);
960 k_flags |= HVhek_UTF8;
962 k_flags &= ~HVhek_UTF8;
963 if (key != keysave) {
964 if (k_flags & HVhek_FREEKEY) {
965 /* This shouldn't happen if our caller does what we expect,
966 but strictly the API allows it. */
969 k_flags |= HVhek_WASUTF8 | HVhek_FREEKEY;
971 HvHASKFLAGS_on(MUTABLE_SV(hv));
975 PERL_HASH_INTERNAL(hash, key, klen);
977 if (keysv && (SvIsCOW_shared_hash(keysv))) {
978 hash = SvSHARED_HASH(keysv);
980 PERL_HASH(hash, key, klen);
984 masked_flags = (k_flags & HVhek_MASK);
986 first_entry = oentry = &(HvARRAY(hv))[hash & (I32) HvMAX(hv)];
988 for (; entry; oentry = &HeNEXT(entry), entry = *oentry) {
990 U8 mro_changes = 0; /* 1 = isa; 2 = package moved */
994 if (HeHASH(entry) != hash) /* strings can't be equal */
996 if (HeKLEN(entry) != (I32)klen)
998 if (HeKEY(entry) != key && memNE(HeKEY(entry),key,klen)) /* is this it? */
1000 if ((HeKFLAGS(entry) ^ masked_flags) & HVhek_UTF8)
1003 if (hv == PL_strtab) {
1004 if (k_flags & HVhek_FREEKEY)
1006 Perl_croak(aTHX_ S_strtab_error, "delete");
1009 /* if placeholder is here, it's already been deleted.... */
1010 if (HeVAL(entry) == &PL_sv_placeholder) {
1011 if (k_flags & HVhek_FREEKEY)
1015 if (SvREADONLY(hv) && HeVAL(entry) && SvREADONLY(HeVAL(entry))) {
1016 hv_notallowed(k_flags, key, klen,
1017 "Attempt to delete readonly key '%"SVf"' from"
1018 " a restricted hash");
1020 if (k_flags & HVhek_FREEKEY)
1023 /* If this is a stash and the key ends with ::, then someone is
1024 * deleting a package.
1026 if (HeVAL(entry) && HvENAME_get(hv)) {
1027 gv = (GV *)HeVAL(entry);
1028 if (keysv) key = SvPV(keysv, klen);
1029 if (klen > 1 && key[klen-2] == ':' && key[klen-1] == ':'
1030 && (klen != 6 || hv!=PL_defstash || memNE(key,"main::",6))
1031 && SvTYPE(gv) == SVt_PVGV && (stash = GvHV((GV *)gv))
1032 && HvENAME_get(stash)) {
1033 /* A previous version of this code checked that the
1034 * GV was still in the symbol table by fetching the
1035 * GV with its name. That is not necessary (and
1036 * sometimes incorrect), as HvENAME cannot be set
1037 * on hv if it is not in the symtab. */
1039 /* Hang on to it for a bit. */
1040 SvREFCNT_inc_simple_void_NN(
1041 sv_2mortal((SV *)gv)
1044 else if (klen == 3 && strnEQ(key, "ISA", 3))
1048 if (d_flags & G_DISCARD)
1051 sv = sv_2mortal(HeVAL(entry));
1052 HeVAL(entry) = &PL_sv_placeholder;
1056 * If a restricted hash, rather than really deleting the entry, put
1057 * a placeholder there. This marks the key as being "approved", so
1058 * we can still access via not-really-existing key without raising
1061 if (SvREADONLY(hv)) {
1062 SvREFCNT_dec(HeVAL(entry));
1063 HeVAL(entry) = &PL_sv_placeholder;
1064 /* We'll be saving this slot, so the number of allocated keys
1065 * doesn't go down, but the number placeholders goes up */
1066 HvPLACEHOLDERS(hv)++;
1068 *oentry = HeNEXT(entry);
1069 if (SvOOK(hv) && entry == HvAUX(hv)->xhv_eiter /* HvEITER(hv) */)
1072 hv_free_ent(hv, entry);
1073 xhv->xhv_keys--; /* HvTOTALKEYS(hv)-- */
1074 if (xhv->xhv_keys == 0)
1075 HvHASKFLAGS_off(hv);
1078 if (mro_changes == 1) mro_isa_changed_in(hv);
1079 else if (mro_changes == 2)
1080 mro_package_moved(NULL, stash, gv, NULL, 1);
1084 if (SvREADONLY(hv)) {
1085 hv_notallowed(k_flags, key, klen,
1086 "Attempt to delete disallowed key '%"SVf"' from"
1087 " a restricted hash");
1090 if (k_flags & HVhek_FREEKEY)
1096 S_hsplit(pTHX_ HV *hv)
1099 register XPVHV* const xhv = (XPVHV*)SvANY(hv);
1100 const I32 oldsize = (I32) xhv->xhv_max+1; /* HvMAX(hv)+1 (sick) */
1101 register I32 newsize = oldsize * 2;
1103 char *a = (char*) HvARRAY(hv);
1105 int longest_chain = 0;
1108 PERL_ARGS_ASSERT_HSPLIT;
1110 /*PerlIO_printf(PerlIO_stderr(), "hsplit called for %p which had %d\n",
1111 (void*)hv, (int) oldsize);*/
1113 if (HvPLACEHOLDERS_get(hv) && !SvREADONLY(hv)) {
1114 /* Can make this clear any placeholders first for non-restricted hashes,
1115 even though Storable rebuilds restricted hashes by putting in all the
1116 placeholders (first) before turning on the readonly flag, because
1117 Storable always pre-splits the hash. */
1118 hv_clear_placeholders(hv);
1122 #if defined(STRANGE_MALLOC) || defined(MYMALLOC)
1123 Renew(a, PERL_HV_ARRAY_ALLOC_BYTES(newsize)
1124 + (SvOOK(hv) ? sizeof(struct xpvhv_aux) : 0), char);
1130 Move(&a[oldsize * sizeof(HE*)], &a[newsize * sizeof(HE*)], 1, struct xpvhv_aux);
1133 Newx(a, PERL_HV_ARRAY_ALLOC_BYTES(newsize)
1134 + (SvOOK(hv) ? sizeof(struct xpvhv_aux) : 0), char);
1139 Copy(HvARRAY(hv), a, oldsize * sizeof(HE*), char);
1141 Copy(HvAUX(hv), &a[newsize * sizeof(HE*)], 1, struct xpvhv_aux);
1143 Safefree(HvARRAY(hv));
1147 Zero(&a[oldsize * sizeof(HE*)], (newsize-oldsize) * sizeof(HE*), char); /* zero 2nd half*/
1148 xhv->xhv_max = --newsize; /* HvMAX(hv) = --newsize */
1149 HvARRAY(hv) = (HE**) a;
1152 for (i=0; i<oldsize; i++,aep++) {
1153 int left_length = 0;
1154 int right_length = 0;
1159 if (!entry) /* non-existent */
1163 if ((HeHASH(entry) & newsize) != (U32)i) {
1164 *oentry = HeNEXT(entry);
1165 HeNEXT(entry) = *bep;
1170 oentry = &HeNEXT(entry);
1175 /* I think we don't actually need to keep track of the longest length,
1176 merely flag if anything is too long. But for the moment while
1177 developing this code I'll track it. */
1178 if (left_length > longest_chain)
1179 longest_chain = left_length;
1180 if (right_length > longest_chain)
1181 longest_chain = right_length;
1185 /* Pick your policy for "hashing isn't working" here: */
1186 if (longest_chain <= HV_MAX_LENGTH_BEFORE_SPLIT /* split worked? */
1191 if (hv == PL_strtab) {
1192 /* Urg. Someone is doing something nasty to the string table.
1197 /* Awooga. Awooga. Pathological data. */
1198 /*PerlIO_printf(PerlIO_stderr(), "%p %d of %d with %d/%d buckets\n", (void*)hv,
1199 longest_chain, HvTOTALKEYS(hv), HvFILL(hv), 1+HvMAX(hv));*/
1202 Newxz(a, PERL_HV_ARRAY_ALLOC_BYTES(newsize)
1203 + (SvOOK(hv) ? sizeof(struct xpvhv_aux) : 0), char);
1205 Copy(HvAUX(hv), &a[newsize * sizeof(HE*)], 1, struct xpvhv_aux);
1208 was_shared = HvSHAREKEYS(hv);
1210 HvSHAREKEYS_off(hv);
1215 for (i=0; i<newsize; i++,aep++) {
1216 register HE *entry = *aep;
1218 /* We're going to trash this HE's next pointer when we chain it
1219 into the new hash below, so store where we go next. */
1220 HE * const next = HeNEXT(entry);
1225 PERL_HASH_INTERNAL(hash, HeKEY(entry), HeKLEN(entry));
1230 = save_hek_flags(HeKEY(entry), HeKLEN(entry),
1231 hash, HeKFLAGS(entry));
1232 unshare_hek (HeKEY_hek(entry));
1233 HeKEY_hek(entry) = new_hek;
1235 /* Not shared, so simply write the new hash in. */
1236 HeHASH(entry) = hash;
1238 /*PerlIO_printf(PerlIO_stderr(), "%d ", HeKFLAGS(entry));*/
1239 HEK_REHASH_on(HeKEY_hek(entry));
1240 /*PerlIO_printf(PerlIO_stderr(), "%d\n", HeKFLAGS(entry));*/
1242 /* Copy oentry to the correct new chain. */
1243 bep = ((HE**)a) + (hash & (I32) xhv->xhv_max);
1244 HeNEXT(entry) = *bep;
1250 Safefree (HvARRAY(hv));
1251 HvARRAY(hv) = (HE **)a;
1255 Perl_hv_ksplit(pTHX_ HV *hv, IV newmax)
1258 register XPVHV* xhv = (XPVHV*)SvANY(hv);
1259 const I32 oldsize = (I32) xhv->xhv_max+1; /* HvMAX(hv)+1 (sick) */
1260 register I32 newsize;
1265 PERL_ARGS_ASSERT_HV_KSPLIT;
1267 newsize = (I32) newmax; /* possible truncation here */
1268 if (newsize != newmax || newmax <= oldsize)
1270 while ((newsize & (1 + ~newsize)) != newsize) {
1271 newsize &= ~(newsize & (1 + ~newsize)); /* get proper power of 2 */
1273 if (newsize < newmax)
1275 if (newsize < newmax)
1276 return; /* overflow detection */
1278 a = (char *) HvARRAY(hv);
1281 #if defined(STRANGE_MALLOC) || defined(MYMALLOC)
1282 Renew(a, PERL_HV_ARRAY_ALLOC_BYTES(newsize)
1283 + (SvOOK(hv) ? sizeof(struct xpvhv_aux) : 0), char);
1289 Copy(&a[oldsize * sizeof(HE*)], &a[newsize * sizeof(HE*)], 1, struct xpvhv_aux);
1292 Newx(a, PERL_HV_ARRAY_ALLOC_BYTES(newsize)
1293 + (SvOOK(hv) ? sizeof(struct xpvhv_aux) : 0), char);
1298 Copy(HvARRAY(hv), a, oldsize * sizeof(HE*), char);
1300 Copy(HvAUX(hv), &a[newsize * sizeof(HE*)], 1, struct xpvhv_aux);
1302 Safefree(HvARRAY(hv));
1305 Zero(&a[oldsize * sizeof(HE*)], (newsize-oldsize) * sizeof(HE*), char); /* zero 2nd half*/
1308 Newxz(a, PERL_HV_ARRAY_ALLOC_BYTES(newsize), char);
1310 xhv->xhv_max = --newsize; /* HvMAX(hv) = --newsize */
1311 HvARRAY(hv) = (HE **) a;
1312 if (!xhv->xhv_keys /* !HvTOTALKEYS(hv) */) /* skip rest if no entries */
1316 for (i=0; i<oldsize; i++,aep++) {
1320 if (!entry) /* non-existent */
1323 register I32 j = (HeHASH(entry) & newsize);
1327 *oentry = HeNEXT(entry);
1328 HeNEXT(entry) = aep[j];
1332 oentry = &HeNEXT(entry);
1339 Perl_newHVhv(pTHX_ HV *ohv)
1342 HV * const hv = newHV();
1345 if (!ohv || !HvTOTALKEYS(ohv))
1347 hv_max = HvMAX(ohv);
1349 if (!SvMAGICAL((const SV *)ohv)) {
1350 /* It's an ordinary hash, so copy it fast. AMS 20010804 */
1352 const bool shared = !!HvSHAREKEYS(ohv);
1353 HE **ents, ** const oents = (HE **)HvARRAY(ohv);
1355 Newx(a, PERL_HV_ARRAY_ALLOC_BYTES(hv_max+1), char);
1358 /* In each bucket... */
1359 for (i = 0; i <= hv_max; i++) {
1361 HE *oent = oents[i];
1368 /* Copy the linked list of entries. */
1369 for (; oent; oent = HeNEXT(oent)) {
1370 const U32 hash = HeHASH(oent);
1371 const char * const key = HeKEY(oent);
1372 const STRLEN len = HeKLEN(oent);
1373 const int flags = HeKFLAGS(oent);
1374 HE * const ent = new_HE();
1375 SV *const val = HeVAL(oent);
1377 HeVAL(ent) = SvIMMORTAL(val) ? val : newSVsv(val);
1379 = shared ? share_hek_flags(key, len, hash, flags)
1380 : save_hek_flags(key, len, hash, flags);
1391 HvTOTALKEYS(hv) = HvTOTALKEYS(ohv);
1395 /* Iterate over ohv, copying keys and values one at a time. */
1397 const I32 riter = HvRITER_get(ohv);
1398 HE * const eiter = HvEITER_get(ohv);
1399 STRLEN hv_fill = HvFILL(ohv);
1401 /* Can we use fewer buckets? (hv_max is always 2^n-1) */
1402 while (hv_max && hv_max + 1 >= hv_fill * 2)
1403 hv_max = hv_max / 2;
1407 while ((entry = hv_iternext_flags(ohv, 0))) {
1408 SV *const val = HeVAL(entry);
1409 (void)hv_store_flags(hv, HeKEY(entry), HeKLEN(entry),
1410 SvIMMORTAL(val) ? val : newSVsv(val),
1411 HeHASH(entry), HeKFLAGS(entry));
1413 HvRITER_set(ohv, riter);
1414 HvEITER_set(ohv, eiter);
1421 =for apidoc Am|HV *|hv_copy_hints_hv|HV *ohv
1423 A specialised version of L</newHVhv> for copying C<%^H>. I<ohv> must be
1424 a pointer to a hash (which may have C<%^H> magic, but should be generally
1425 non-magical), or C<NULL> (interpreted as an empty hash). The content
1426 of I<ohv> is copied to a new hash, which has the C<%^H>-specific magic
1427 added to it. A pointer to the new hash is returned.
1433 Perl_hv_copy_hints_hv(pTHX_ HV *const ohv)
1435 HV * const hv = newHV();
1437 if (ohv && HvTOTALKEYS(ohv)) {
1438 STRLEN hv_max = HvMAX(ohv);
1439 STRLEN hv_fill = HvFILL(ohv);
1441 const I32 riter = HvRITER_get(ohv);
1442 HE * const eiter = HvEITER_get(ohv);
1444 while (hv_max && hv_max + 1 >= hv_fill * 2)
1445 hv_max = hv_max / 2;
1449 while ((entry = hv_iternext_flags(ohv, 0))) {
1450 SV *const sv = newSVsv(HeVAL(entry));
1451 SV *heksv = newSVhek(HeKEY_hek(entry));
1452 sv_magic(sv, NULL, PERL_MAGIC_hintselem,
1453 (char *)heksv, HEf_SVKEY);
1454 SvREFCNT_dec(heksv);
1455 (void)hv_store_flags(hv, HeKEY(entry), HeKLEN(entry),
1456 sv, HeHASH(entry), HeKFLAGS(entry));
1458 HvRITER_set(ohv, riter);
1459 HvEITER_set(ohv, eiter);
1461 hv_magic(hv, NULL, PERL_MAGIC_hints);
1466 Perl_hv_free_ent(pTHX_ HV *hv, register HE *entry)
1471 PERL_ARGS_ASSERT_HV_FREE_ENT;
1476 if (val && isGV(val) && isGV_with_GP(val) && GvCVu(val) && HvENAME(hv))
1477 mro_method_changed_in(hv); /* deletion of method from stash */
1479 if (HeKLEN(entry) == HEf_SVKEY) {
1480 SvREFCNT_dec(HeKEY_sv(entry));
1481 Safefree(HeKEY_hek(entry));
1483 else if (HvSHAREKEYS(hv))
1484 unshare_hek(HeKEY_hek(entry));
1486 Safefree(HeKEY_hek(entry));
1492 Perl_hv_delayfree_ent(pTHX_ HV *hv, register HE *entry)
1496 PERL_ARGS_ASSERT_HV_DELAYFREE_ENT;
1500 /* SvREFCNT_inc to counter the SvREFCNT_dec in hv_free_ent */
1501 sv_2mortal(SvREFCNT_inc(HeVAL(entry))); /* free between statements */
1502 if (HeKLEN(entry) == HEf_SVKEY) {
1503 sv_2mortal(SvREFCNT_inc(HeKEY_sv(entry)));
1505 hv_free_ent(hv, entry);
1509 =for apidoc hv_clear
1511 Clears a hash, making it empty.
1517 Perl_hv_clear(pTHX_ HV *hv)
1520 register XPVHV* xhv;
1524 DEBUG_A(Perl_hv_assert(aTHX_ hv));
1526 xhv = (XPVHV*)SvANY(hv);
1528 if (SvREADONLY(hv) && HvARRAY(hv) != NULL) {
1529 /* restricted hash: convert all keys to placeholders */
1531 for (i = 0; i <= xhv->xhv_max; i++) {
1532 HE *entry = (HvARRAY(hv))[i];
1533 for (; entry; entry = HeNEXT(entry)) {
1534 /* not already placeholder */
1535 if (HeVAL(entry) != &PL_sv_placeholder) {
1536 if (HeVAL(entry) && SvREADONLY(HeVAL(entry))) {
1537 SV* const keysv = hv_iterkeysv(entry);
1539 "Attempt to delete readonly key '%"SVf"' from a restricted hash",
1542 SvREFCNT_dec(HeVAL(entry));
1543 HeVAL(entry) = &PL_sv_placeholder;
1544 HvPLACEHOLDERS(hv)++;
1552 HvPLACEHOLDERS_set(hv, 0);
1554 Zero(HvARRAY(hv), xhv->xhv_max+1 /* HvMAX(hv)+1 */, HE*);
1557 mg_clear(MUTABLE_SV(hv));
1559 HvHASKFLAGS_off(hv);
1564 mro_isa_changed_in(hv);
1565 HvEITER_set(hv, NULL);
1570 =for apidoc hv_clear_placeholders
1572 Clears any placeholders from a hash. If a restricted hash has any of its keys
1573 marked as readonly and the key is subsequently deleted, the key is not actually
1574 deleted but is marked by assigning it a value of &PL_sv_placeholder. This tags
1575 it so it will be ignored by future operations such as iterating over the hash,
1576 but will still allow the hash to have a value reassigned to the key at some
1577 future point. This function clears any such placeholder keys from the hash.
1578 See Hash::Util::lock_keys() for an example of its use.
1584 Perl_hv_clear_placeholders(pTHX_ HV *hv)
1587 const U32 items = (U32)HvPLACEHOLDERS_get(hv);
1589 PERL_ARGS_ASSERT_HV_CLEAR_PLACEHOLDERS;
1592 clear_placeholders(hv, items);
1596 S_clear_placeholders(pTHX_ HV *hv, U32 items)
1601 PERL_ARGS_ASSERT_CLEAR_PLACEHOLDERS;
1608 /* Loop down the linked list heads */
1610 HE **oentry = &(HvARRAY(hv))[i];
1613 while ((entry = *oentry)) {
1614 if (HeVAL(entry) == &PL_sv_placeholder) {
1615 *oentry = HeNEXT(entry);
1616 if (entry == HvEITER_get(hv))
1619 hv_free_ent(hv, entry);
1623 HvTOTALKEYS(hv) -= (IV)HvPLACEHOLDERS_get(hv);
1624 if (HvKEYS(hv) == 0)
1625 HvHASKFLAGS_off(hv);
1626 HvPLACEHOLDERS_set(hv, 0);
1630 oentry = &HeNEXT(entry);
1635 /* You can't get here, hence assertion should always fail. */
1636 assert (items == 0);
1641 S_hfreeentries(pTHX_ HV *hv)
1643 /* This is the array that we're going to restore */
1644 HE **const orig_array = HvARRAY(hv);
1645 HE **tmp_array = NULL;
1646 const bool has_aux = SvOOK(hv);
1647 struct xpvhv_aux * current_aux = NULL;
1650 PERL_ARGS_ASSERT_HFREEENTRIES;
1655 /* orig_array remains unchanged throughout the loop. If after freeing all
1656 the entries it turns out that one of the little blighters has triggered
1657 an action that has caused HvARRAY to be re-allocated, then we set
1658 array to the new HvARRAY, and try again. */
1661 /* This is the one we're going to try to empty. First time round
1662 it's the original array. (Hopefully there will only be 1 time
1664 HE ** const array = HvARRAY(hv);
1667 struct xpvhv_aux *iter = SvOOK(hv) ? HvAUX(hv) : NULL;
1669 /* make everyone else think the array is empty, so that the destructors
1670 * called for freed entries can't recursively mess with us */
1676 SvFLAGS(hv) &= ~SVf_OOK; /* Goodbye, aux structure. */
1677 /* What aux structure? */
1678 /* (But we still have a pointer to it in iter.) */
1680 /* Copy the name and MRO stuff to a new aux structure
1682 if (iter->xhv_name || iter->xhv_mro_meta) {
1683 struct xpvhv_aux * const newaux = hv_auxinit(hv);
1684 newaux->xhv_name = iter->xhv_name;
1685 newaux->xhv_name_count = iter->xhv_name_count;
1686 iter->xhv_name = NULL;
1687 newaux->xhv_mro_meta = iter->xhv_mro_meta;
1688 iter->xhv_mro_meta = NULL;
1691 /* Because we have taken xhv_name and
1692 xhv_mro_meta out, the only allocated
1693 pointers in the aux structure that might exist are the back-
1694 reference array and xhv_eiter.
1697 /* weak references: if called from sv_clear(), the backrefs
1698 * should already have been killed; if there are any left, its
1699 * because we're doing hv_clear() or hv_undef(), and the HV
1700 * will continue to live.
1701 * Because while freeing the entries we fake up a NULL HvARRAY
1702 * (and hence HvAUX), we need to store the backref array
1703 * somewhere else; but it still needs to be visible in case
1704 * any the things we free happen to call sv_del_backref().
1705 * We do this by storing it in magic instead.
1706 * If, during the entry freeing, a destructor happens to add
1707 * a new weak backref, then sv_add_backref will look in both
1708 * places (magic in HvAUX) for the AV, but will create a new
1709 * AV in HvAUX if it can't find one (if it finds it in magic,
1710 * it moves it back into HvAUX. So at the end of the iteration
1711 * we have to allow for this. */
1714 if (iter->xhv_backreferences) {
1715 if (SvTYPE(iter->xhv_backreferences) == SVt_PVAV) {
1716 /* The sv_magic will increase the reference count of the AV,
1717 so we need to drop it first. */
1718 SvREFCNT_dec(iter->xhv_backreferences);
1719 if (AvFILLp(iter->xhv_backreferences) == -1) {
1720 /* Turns out that the array is empty. Just free it. */
1721 SvREFCNT_dec(iter->xhv_backreferences);
1724 sv_magic(MUTABLE_SV(hv),
1725 MUTABLE_SV(iter->xhv_backreferences),
1726 PERL_MAGIC_backref, NULL, 0);
1731 sv_magic(MUTABLE_SV(hv), NULL, PERL_MAGIC_backref, NULL, 0);
1732 mg = mg_find(MUTABLE_SV(hv), PERL_MAGIC_backref);
1733 mg->mg_obj = (SV*)iter->xhv_backreferences;
1735 iter->xhv_backreferences = NULL;
1738 entry = iter->xhv_eiter; /* HvEITER(hv) */
1739 if (entry && HvLAZYDEL(hv)) { /* was deleted earlier? */
1741 hv_free_ent(hv, entry);
1743 iter->xhv_riter = -1; /* HvRITER(hv) = -1 */
1744 iter->xhv_eiter = NULL; /* HvEITER(hv) = NULL */
1746 /* There are now no allocated pointers in the aux structure. */
1749 /* If there are no keys, there is nothing left to free. */
1750 if (!((XPVHV*) SvANY(hv))->xhv_keys) break;
1752 /* Since we have removed the HvARRAY (and possibly replaced it by
1753 calling hv_auxinit), set the number of keys accordingly. */
1754 ((XPVHV*) SvANY(hv))->xhv_keys = 0;
1757 /* Loop down the linked list heads */
1758 HE *entry = array[i];
1761 register HE * const oentry = entry;
1762 entry = HeNEXT(entry);
1763 hv_free_ent(hv, oentry);
1767 /* As there are no allocated pointers in the aux structure, it's now
1768 safe to free the array we just cleaned up, if it's not the one we're
1769 going to put back. */
1770 if (array != orig_array) {
1775 /* Good. No-one added anything this time round. */
1779 if (--attempts == 0) {
1780 Perl_die(aTHX_ "panic: hfreeentries failed to free hash - something is repeatedly re-creating entries");
1784 /* Set aside the current array for now, in case we still need it. */
1785 if (SvOOK(hv)) current_aux = HvAUX(hv);
1786 if (HvARRAY(hv) && HvARRAY(hv) != orig_array)
1787 tmp_array = HvARRAY(hv);
1789 HvARRAY(hv) = orig_array;
1792 SvFLAGS(hv) |= SVf_OOK;
1794 SvFLAGS(hv) &=~SVf_OOK;
1796 /* If the hash was actually a symbol table, put the name and MRO
1799 struct xpvhv_aux * const aux
1800 = SvOOK(hv) ? HvAUX(hv) : hv_auxinit(hv);
1801 aux->xhv_name = current_aux->xhv_name;
1802 aux->xhv_name_count = current_aux->xhv_name_count;
1803 aux->xhv_mro_meta = current_aux->xhv_mro_meta;
1806 if (tmp_array) Safefree(tmp_array);
1810 =for apidoc hv_undef
1818 Perl_hv_undef(pTHX_ HV *hv)
1821 register XPVHV* xhv;
1826 DEBUG_A(Perl_hv_assert(aTHX_ hv));
1827 xhv = (XPVHV*)SvANY(hv);
1829 if ((name = HvENAME_get(hv)) && PL_phase != PERL_PHASE_DESTRUCT)
1831 /* Delete the @ISA element before calling mro_package_moved, so it
1833 (void)hv_delete(hv, "ISA", 3, G_DISCARD);
1834 mro_package_moved(NULL, hv, NULL, name, HvENAMELEN_get(hv));
1837 if (name || (name = HvNAME(hv))) {
1839 (void)hv_delete(PL_stashcache, name, HvNAMELEN_get(hv), G_DISCARD);
1840 hv_name_set(hv, NULL, 0, 0);
1844 struct xpvhv_aux * const aux = HvAUX(hv);
1845 struct mro_meta *meta;
1846 if (aux->xhv_name) {
1847 if (PL_stashcache && (name = HvNAME(hv)))
1848 (void)hv_delete(PL_stashcache, name, HvNAMELEN_get(hv), G_DISCARD);
1849 hv_name_set(hv, NULL, 0, 0);
1851 if((meta = aux->xhv_mro_meta)) {
1852 if (meta->mro_linear_all) {
1853 SvREFCNT_dec(MUTABLE_SV(meta->mro_linear_all));
1854 meta->mro_linear_all = NULL;
1855 /* This is just acting as a shortcut pointer. */
1856 meta->mro_linear_current = NULL;
1857 } else if (meta->mro_linear_current) {
1858 /* Only the current MRO is stored, so this owns the data.
1860 SvREFCNT_dec(meta->mro_linear_current);
1861 meta->mro_linear_current = NULL;
1863 if(meta->mro_nextmethod) SvREFCNT_dec(meta->mro_nextmethod);
1864 SvREFCNT_dec(meta->isa);
1866 aux->xhv_mro_meta = NULL;
1869 SvFLAGS(hv) &= ~SVf_OOK;
1870 Safefree(HvARRAY(hv));
1871 xhv->xhv_max = 7; /* HvMAX(hv) = 7 (it's a normal hash) */
1873 HvPLACEHOLDERS_set(hv, 0);
1876 mg_clear(MUTABLE_SV(hv));
1882 Returns the number of hash buckets that happen to be in use. This function is
1883 wrapped by the macro C<HvFILL>.
1885 Previously this value was stored in the HV structure, rather than being
1886 calculated on demand.
1892 Perl_hv_fill(pTHX_ HV const *const hv)
1895 HE **ents = HvARRAY(hv);
1897 PERL_ARGS_ASSERT_HV_FILL;
1900 HE *const *const last = ents + HvMAX(hv);
1901 count = last + 1 - ents;
1906 } while (++ents <= last);
1911 static struct xpvhv_aux*
1912 S_hv_auxinit(HV *hv) {
1913 struct xpvhv_aux *iter;
1916 PERL_ARGS_ASSERT_HV_AUXINIT;
1919 Newxz(array, PERL_HV_ARRAY_ALLOC_BYTES(HvMAX(hv) + 1)
1920 + sizeof(struct xpvhv_aux), char);
1922 array = (char *) HvARRAY(hv);
1923 Renew(array, PERL_HV_ARRAY_ALLOC_BYTES(HvMAX(hv) + 1)
1924 + sizeof(struct xpvhv_aux), char);
1926 HvARRAY(hv) = (HE**) array;
1927 /* SvOOK_on(hv) attacks the IV flags. */
1928 SvFLAGS(hv) |= SVf_OOK;
1931 iter->xhv_riter = -1; /* HvRITER(hv) = -1 */
1932 iter->xhv_eiter = NULL; /* HvEITER(hv) = NULL */
1934 iter->xhv_name_count = 0;
1935 iter->xhv_backreferences = 0;
1936 iter->xhv_mro_meta = NULL;
1941 =for apidoc hv_iterinit
1943 Prepares a starting point to traverse a hash table. Returns the number of
1944 keys in the hash (i.e. the same as C<HvKEYS(hv)>). The return value is
1945 currently only meaningful for hashes without tie magic.
1947 NOTE: Before version 5.004_65, C<hv_iterinit> used to return the number of
1948 hash buckets that happen to be in use. If you still need that esoteric
1949 value, you can get it through the macro C<HvFILL(hv)>.
1956 Perl_hv_iterinit(pTHX_ HV *hv)
1958 PERL_ARGS_ASSERT_HV_ITERINIT;
1960 /* FIXME: Are we not NULL, or do we croak? Place bets now! */
1963 Perl_croak(aTHX_ "Bad hash");
1966 struct xpvhv_aux * const iter = HvAUX(hv);
1967 HE * const entry = iter->xhv_eiter; /* HvEITER(hv) */
1968 if (entry && HvLAZYDEL(hv)) { /* was deleted earlier? */
1970 hv_free_ent(hv, entry);
1972 iter->xhv_riter = -1; /* HvRITER(hv) = -1 */
1973 iter->xhv_eiter = NULL; /* HvEITER(hv) = NULL */
1978 /* used to be xhv->xhv_fill before 5.004_65 */
1979 return HvTOTALKEYS(hv);
1983 Perl_hv_riter_p(pTHX_ HV *hv) {
1984 struct xpvhv_aux *iter;
1986 PERL_ARGS_ASSERT_HV_RITER_P;
1989 Perl_croak(aTHX_ "Bad hash");
1991 iter = SvOOK(hv) ? HvAUX(hv) : hv_auxinit(hv);
1992 return &(iter->xhv_riter);
1996 Perl_hv_eiter_p(pTHX_ HV *hv) {
1997 struct xpvhv_aux *iter;
1999 PERL_ARGS_ASSERT_HV_EITER_P;
2002 Perl_croak(aTHX_ "Bad hash");
2004 iter = SvOOK(hv) ? HvAUX(hv) : hv_auxinit(hv);
2005 return &(iter->xhv_eiter);
2009 Perl_hv_riter_set(pTHX_ HV *hv, I32 riter) {
2010 struct xpvhv_aux *iter;
2012 PERL_ARGS_ASSERT_HV_RITER_SET;
2015 Perl_croak(aTHX_ "Bad hash");
2023 iter = hv_auxinit(hv);
2025 iter->xhv_riter = riter;
2029 Perl_hv_eiter_set(pTHX_ HV *hv, HE *eiter) {
2030 struct xpvhv_aux *iter;
2032 PERL_ARGS_ASSERT_HV_EITER_SET;
2035 Perl_croak(aTHX_ "Bad hash");
2040 /* 0 is the default so don't go malloc()ing a new structure just to
2045 iter = hv_auxinit(hv);
2047 iter->xhv_eiter = eiter;
2051 Perl_hv_name_set(pTHX_ HV *hv, const char *name, U32 len, U32 flags)
2054 struct xpvhv_aux *iter;
2058 PERL_ARGS_ASSERT_HV_NAME_SET;
2059 PERL_UNUSED_ARG(flags);
2062 Perl_croak(aTHX_ "panic: hv name too long (%"UVuf")", (UV) len);
2066 if (iter->xhv_name) {
2067 if(iter->xhv_name_count) {
2069 HEK ** const name = (HEK **)HvAUX(hv)->xhv_name;
2070 HEK **hekp = name + (
2071 iter->xhv_name_count < 0
2072 ? -iter->xhv_name_count
2073 : iter->xhv_name_count
2075 while(hekp-- > name+1)
2076 unshare_hek_or_pvn(*hekp, 0, 0, 0);
2077 /* The first elem may be null. */
2078 if(*name) unshare_hek_or_pvn(*name, 0, 0, 0);
2080 spot = &iter->xhv_name;
2081 iter->xhv_name_count = 0;
2084 spot = (HEK **)iter->xhv_name;
2085 if(iter->xhv_name_count > 0) {
2086 /* shift some things over */
2087 Renew(spot, iter->xhv_name_count, HEK *);
2088 spot[iter->xhv_name_count++] = spot[1];
2092 unshare_hek_or_pvn(*spot, 0, 0, 0);
2097 unshare_hek_or_pvn(iter->xhv_name, 0, 0, 0);
2098 spot = &iter->xhv_name;
2101 else spot = &iter->xhv_name;
2106 iter = hv_auxinit(hv);
2107 spot = &iter->xhv_name;
2109 PERL_HASH(hash, name, len);
2110 *spot = name ? share_hek(name, len, hash) : NULL;
2111 iter->xhv_name_count = 0;
2115 =for apidoc hv_ename_add
2117 Adds a name to a stash's internal list of effective names. See
2120 This is called when a stash is assigned to a new location in the symbol
2127 Perl_hv_ename_add(pTHX_ HV *hv, const char *name, U32 len)
2130 struct xpvhv_aux *aux = SvOOK(hv) ? HvAUX(hv) : hv_auxinit(hv);
2133 PERL_ARGS_ASSERT_HV_ENAME_ADD;
2136 Perl_croak(aTHX_ "panic: hv name too long (%"UVuf")", (UV) len);
2138 PERL_HASH(hash, name, len);
2140 if (aux->xhv_name_count) {
2141 HEK ** const xhv_name = (HEK **)aux->xhv_name;
2142 I32 count = aux->xhv_name_count;
2143 HEK **hekp = xhv_name + (count < 0 ? -count : count);
2144 while (hekp-- > xhv_name)
2146 HEK_LEN(*hekp) == (I32)len && memEQ(HEK_KEY(*hekp), name, len)
2148 if (hekp == xhv_name && count < 0)
2149 aux->xhv_name_count = -count;
2152 if (count < 0) aux->xhv_name_count--, count = -count;
2153 else aux->xhv_name_count++;
2154 Renewc(aux->xhv_name, count + 1, HEK *, HEK);
2155 ((HEK **)aux->xhv_name)[count] = share_hek(name, len, hash);
2158 HEK *existing_name = aux->xhv_name;
2160 existing_name && HEK_LEN(existing_name) == (I32)len
2161 && memEQ(HEK_KEY(existing_name), name, len)
2163 Newxc(aux->xhv_name, 2, HEK *, HEK);
2164 aux->xhv_name_count = existing_name ? 2 : -2;
2165 *(HEK **)aux->xhv_name = existing_name;
2166 ((HEK **)aux->xhv_name)[1] = share_hek(name, len, hash);
2171 =for apidoc hv_ename_delete
2173 Removes a name from a stash's internal list of effective names. If this is
2174 the name returned by C<HvENAME>, then another name in the list will take
2175 its place (C<HvENAME> will use it).
2177 This is called when a stash is deleted from the symbol table.
2183 Perl_hv_ename_delete(pTHX_ HV *hv, const char *name, U32 len)
2186 struct xpvhv_aux *aux;
2188 PERL_ARGS_ASSERT_HV_ENAME_DELETE;
2191 Perl_croak(aTHX_ "panic: hv name too long (%"UVuf")", (UV) len);
2193 if (!SvOOK(hv)) return;
2196 if (!aux->xhv_name) return;
2198 if (aux->xhv_name_count) {
2199 HEK ** const namep = (HEK **)aux->xhv_name;
2200 I32 const count = aux->xhv_name_count;
2201 HEK **victim = namep + (count < 0 ? -count : count);
2202 while (victim-- > namep + 1)
2204 HEK_LEN(*victim) == (I32)len
2205 && memEQ(HEK_KEY(*victim), name, len)
2207 unshare_hek_or_pvn(*victim, 0, 0, 0);
2208 if (count < 0) ++aux->xhv_name_count;
2209 else --aux->xhv_name_count;
2211 (aux->xhv_name_count == 1 || aux->xhv_name_count == -1)
2213 ) { /* if there are none left */
2215 aux->xhv_name = NULL;
2216 aux->xhv_name_count = 0;
2219 /* Move the last one back to fill the empty slot. It
2220 does not matter what order they are in. */
2221 *victim = *(namep + (count < 0 ? -count : count) - 1);
2226 count > 0 && HEK_LEN(*namep) == (I32)len
2227 && memEQ(HEK_KEY(*namep),name,len)
2229 aux->xhv_name_count = -count;
2233 HEK_LEN(aux->xhv_name) == (I32)len
2234 && memEQ(HEK_KEY(aux->xhv_name), name, len)
2236 const HEK * const namehek = aux->xhv_name;
2237 Newxc(aux->xhv_name, 1, HEK *, HEK);
2238 *(const HEK **)aux->xhv_name = namehek;
2239 aux->xhv_name_count = -1;
2244 Perl_hv_backreferences_p(pTHX_ HV *hv) {
2245 struct xpvhv_aux * const iter = SvOOK(hv) ? HvAUX(hv) : hv_auxinit(hv);
2247 PERL_ARGS_ASSERT_HV_BACKREFERENCES_P;
2248 PERL_UNUSED_CONTEXT;
2250 return &(iter->xhv_backreferences);
2254 Perl_hv_kill_backrefs(pTHX_ HV *hv) {
2257 PERL_ARGS_ASSERT_HV_KILL_BACKREFS;
2262 av = HvAUX(hv)->xhv_backreferences;
2265 HvAUX(hv)->xhv_backreferences = 0;
2266 Perl_sv_kill_backrefs(aTHX_ MUTABLE_SV(hv), av);
2267 if (SvTYPE(av) == SVt_PVAV)
2273 hv_iternext is implemented as a macro in hv.h
2275 =for apidoc hv_iternext
2277 Returns entries from a hash iterator. See C<hv_iterinit>.
2279 You may call C<hv_delete> or C<hv_delete_ent> on the hash entry that the
2280 iterator currently points to, without losing your place or invalidating your
2281 iterator. Note that in this case the current entry is deleted from the hash
2282 with your iterator holding the last reference to it. Your iterator is flagged
2283 to free the entry on the next call to C<hv_iternext>, so you must not discard
2284 your iterator immediately else the entry will leak - call C<hv_iternext> to
2285 trigger the resource deallocation.
2287 =for apidoc hv_iternext_flags
2289 Returns entries from a hash iterator. See C<hv_iterinit> and C<hv_iternext>.
2290 The C<flags> value will normally be zero; if HV_ITERNEXT_WANTPLACEHOLDERS is
2291 set the placeholders keys (for restricted hashes) will be returned in addition
2292 to normal keys. By default placeholders are automatically skipped over.
2293 Currently a placeholder is implemented with a value that is
2294 C<&Perl_sv_placeholder>. Note that the implementation of placeholders and
2295 restricted hashes may change, and the implementation currently is
2296 insufficiently abstracted for any change to be tidy.
2302 Perl_hv_iternext_flags(pTHX_ HV *hv, I32 flags)
2305 register XPVHV* xhv;
2309 struct xpvhv_aux *iter;
2311 PERL_ARGS_ASSERT_HV_ITERNEXT_FLAGS;
2314 Perl_croak(aTHX_ "Bad hash");
2316 xhv = (XPVHV*)SvANY(hv);
2319 /* Too many things (well, pp_each at least) merrily assume that you can
2320 call iv_iternext without calling hv_iterinit, so we'll have to deal
2326 oldentry = entry = iter->xhv_eiter; /* HvEITER(hv) */
2327 if (SvMAGICAL(hv) && SvRMAGICAL(hv)) {
2328 if ( ( mg = mg_find((const SV *)hv, PERL_MAGIC_tied) ) ) {
2329 SV * const key = sv_newmortal();
2331 sv_setsv(key, HeSVKEY_force(entry));
2332 SvREFCNT_dec(HeSVKEY(entry)); /* get rid of previous key */
2338 /* one HE per MAGICAL hash */
2339 iter->xhv_eiter = entry = new_HE(); /* HvEITER(hv) = new_HE() */
2341 Newxz(k, HEK_BASESIZE + sizeof(const SV *), char);
2343 HeKEY_hek(entry) = hek;
2344 HeKLEN(entry) = HEf_SVKEY;
2346 magic_nextpack(MUTABLE_SV(hv),mg,key);
2348 /* force key to stay around until next time */
2349 HeSVKEY_set(entry, SvREFCNT_inc_simple_NN(key));
2350 return entry; /* beware, hent_val is not set */
2352 SvREFCNT_dec(HeVAL(entry));
2353 Safefree(HeKEY_hek(entry));
2355 iter->xhv_eiter = NULL; /* HvEITER(hv) = NULL */
2359 #if defined(DYNAMIC_ENV_FETCH) && !defined(__riscos__) /* set up %ENV for iteration */
2360 if (!entry && SvRMAGICAL((const SV *)hv)
2361 && mg_find((const SV *)hv, PERL_MAGIC_env)) {
2364 /* The prime_env_iter() on VMS just loaded up new hash values
2365 * so the iteration count needs to be reset back to the beginning
2369 oldentry = entry = iter->xhv_eiter; /* HvEITER(hv) */
2374 /* hv_iterint now ensures this. */
2375 assert (HvARRAY(hv));
2377 /* At start of hash, entry is NULL. */
2380 entry = HeNEXT(entry);
2381 if (!(flags & HV_ITERNEXT_WANTPLACEHOLDERS)) {
2383 * Skip past any placeholders -- don't want to include them in
2386 while (entry && HeVAL(entry) == &PL_sv_placeholder) {
2387 entry = HeNEXT(entry);
2392 /* Skip the entire loop if the hash is empty. */
2393 if ((flags & HV_ITERNEXT_WANTPLACEHOLDERS)
2394 ? HvTOTALKEYS(hv) : HvUSEDKEYS(hv)) {
2396 /* OK. Come to the end of the current list. Grab the next one. */
2398 iter->xhv_riter++; /* HvRITER(hv)++ */
2399 if (iter->xhv_riter > (I32)xhv->xhv_max /* HvRITER(hv) > HvMAX(hv) */) {
2400 /* There is no next one. End of the hash. */
2401 iter->xhv_riter = -1; /* HvRITER(hv) = -1 */
2404 entry = (HvARRAY(hv))[iter->xhv_riter];
2406 if (!(flags & HV_ITERNEXT_WANTPLACEHOLDERS)) {
2407 /* If we have an entry, but it's a placeholder, don't count it.
2409 while (entry && HeVAL(entry) == &PL_sv_placeholder)
2410 entry = HeNEXT(entry);
2412 /* Will loop again if this linked list starts NULL
2413 (for HV_ITERNEXT_WANTPLACEHOLDERS)
2414 or if we run through it and find only placeholders. */
2418 if (oldentry && HvLAZYDEL(hv)) { /* was deleted earlier? */
2420 hv_free_ent(hv, oldentry);
2423 /*if (HvREHASH(hv) && entry && !HeKREHASH(entry))
2424 PerlIO_printf(PerlIO_stderr(), "Awooga %p %p\n", (void*)hv, (void*)entry);*/
2426 iter->xhv_eiter = entry; /* HvEITER(hv) = entry */
2431 =for apidoc hv_iterkey
2433 Returns the key from the current position of the hash iterator. See
2440 Perl_hv_iterkey(pTHX_ register HE *entry, I32 *retlen)
2442 PERL_ARGS_ASSERT_HV_ITERKEY;
2444 if (HeKLEN(entry) == HEf_SVKEY) {
2446 char * const p = SvPV(HeKEY_sv(entry), len);
2451 *retlen = HeKLEN(entry);
2452 return HeKEY(entry);
2456 /* unlike hv_iterval(), this always returns a mortal copy of the key */
2458 =for apidoc hv_iterkeysv
2460 Returns the key as an C<SV*> from the current position of the hash
2461 iterator. The return value will always be a mortal copy of the key. Also
2468 Perl_hv_iterkeysv(pTHX_ register HE *entry)
2470 PERL_ARGS_ASSERT_HV_ITERKEYSV;
2472 return sv_2mortal(newSVhek(HeKEY_hek(entry)));
2476 =for apidoc hv_iterval
2478 Returns the value from the current position of the hash iterator. See
2485 Perl_hv_iterval(pTHX_ HV *hv, register HE *entry)
2487 PERL_ARGS_ASSERT_HV_ITERVAL;
2489 if (SvRMAGICAL(hv)) {
2490 if (mg_find((const SV *)hv, PERL_MAGIC_tied)) {
2491 SV* const sv = sv_newmortal();
2492 if (HeKLEN(entry) == HEf_SVKEY)
2493 mg_copy(MUTABLE_SV(hv), sv, (char*)HeKEY_sv(entry), HEf_SVKEY);
2495 mg_copy(MUTABLE_SV(hv), sv, HeKEY(entry), HeKLEN(entry));
2499 return HeVAL(entry);
2503 =for apidoc hv_iternextsv
2505 Performs an C<hv_iternext>, C<hv_iterkey>, and C<hv_iterval> in one
2512 Perl_hv_iternextsv(pTHX_ HV *hv, char **key, I32 *retlen)
2514 HE * const he = hv_iternext_flags(hv, 0);
2516 PERL_ARGS_ASSERT_HV_ITERNEXTSV;
2520 *key = hv_iterkey(he, retlen);
2521 return hv_iterval(hv, he);
2528 =for apidoc hv_magic
2530 Adds magic to a hash. See C<sv_magic>.
2535 /* possibly free a shared string if no one has access to it
2536 * len and hash must both be valid for str.
2539 Perl_unsharepvn(pTHX_ const char *str, I32 len, U32 hash)
2541 unshare_hek_or_pvn (NULL, str, len, hash);
2546 Perl_unshare_hek(pTHX_ HEK *hek)
2549 unshare_hek_or_pvn(hek, NULL, 0, 0);
2552 /* possibly free a shared string if no one has access to it
2553 hek if non-NULL takes priority over the other 3, else str, len and hash
2554 are used. If so, len and hash must both be valid for str.
2557 S_unshare_hek_or_pvn(pTHX_ const HEK *hek, const char *str, I32 len, U32 hash)
2560 register XPVHV* xhv;
2562 register HE **oentry;
2564 bool is_utf8 = FALSE;
2566 const char * const save = str;
2567 struct shared_he *he = NULL;
2570 /* Find the shared he which is just before us in memory. */
2571 he = (struct shared_he *)(((char *)hek)
2572 - STRUCT_OFFSET(struct shared_he,
2575 /* Assert that the caller passed us a genuine (or at least consistent)
2577 assert (he->shared_he_he.hent_hek == hek);
2579 if (he->shared_he_he.he_valu.hent_refcount - 1) {
2580 --he->shared_he_he.he_valu.hent_refcount;
2584 hash = HEK_HASH(hek);
2585 } else if (len < 0) {
2586 STRLEN tmplen = -len;
2588 /* See the note in hv_fetch(). --jhi */
2589 str = (char*)bytes_from_utf8((U8*)str, &tmplen, &is_utf8);
2592 k_flags = HVhek_UTF8;
2594 k_flags |= HVhek_WASUTF8 | HVhek_FREEKEY;
2597 /* what follows was the moral equivalent of:
2598 if ((Svp = hv_fetch(PL_strtab, tmpsv, FALSE, hash))) {
2600 hv_delete(PL_strtab, str, len, G_DISCARD, hash);
2602 xhv = (XPVHV*)SvANY(PL_strtab);
2603 /* assert(xhv_array != 0) */
2604 first = oentry = &(HvARRAY(PL_strtab))[hash & (I32) HvMAX(PL_strtab)];
2606 const HE *const he_he = &(he->shared_he_he);
2607 for (entry = *oentry; entry; oentry = &HeNEXT(entry), entry = *oentry) {
2612 const int flags_masked = k_flags & HVhek_MASK;
2613 for (entry = *oentry; entry; oentry = &HeNEXT(entry), entry = *oentry) {
2614 if (HeHASH(entry) != hash) /* strings can't be equal */
2616 if (HeKLEN(entry) != len)
2618 if (HeKEY(entry) != str && memNE(HeKEY(entry),str,len)) /* is this it? */
2620 if (HeKFLAGS(entry) != flags_masked)
2627 if (--entry->he_valu.hent_refcount == 0) {
2628 *oentry = HeNEXT(entry);
2630 xhv->xhv_keys--; /* HvTOTALKEYS(hv)-- */
2635 Perl_ck_warner_d(aTHX_ packWARN(WARN_INTERNAL),
2636 "Attempt to free non-existent shared string '%s'%s"
2638 hek ? HEK_KEY(hek) : str,
2639 ((k_flags & HVhek_UTF8) ? " (utf8)" : "") pTHX__VALUE);
2640 if (k_flags & HVhek_FREEKEY)
2644 /* get a (constant) string ptr from the global string table
2645 * string will get added if it is not already there.
2646 * len and hash must both be valid for str.
2649 Perl_share_hek(pTHX_ const char *str, I32 len, register U32 hash)
2651 bool is_utf8 = FALSE;
2653 const char * const save = str;
2655 PERL_ARGS_ASSERT_SHARE_HEK;
2658 STRLEN tmplen = -len;
2660 /* See the note in hv_fetch(). --jhi */
2661 str = (char*)bytes_from_utf8((U8*)str, &tmplen, &is_utf8);
2663 /* If we were able to downgrade here, then than means that we were passed
2664 in a key which only had chars 0-255, but was utf8 encoded. */
2667 /* If we found we were able to downgrade the string to bytes, then
2668 we should flag that it needs upgrading on keys or each. Also flag
2669 that we need share_hek_flags to free the string. */
2671 flags |= HVhek_WASUTF8 | HVhek_FREEKEY;
2674 return share_hek_flags (str, len, hash, flags);
2678 S_share_hek_flags(pTHX_ const char *str, I32 len, register U32 hash, int flags)
2682 const int flags_masked = flags & HVhek_MASK;
2683 const U32 hindex = hash & (I32) HvMAX(PL_strtab);
2684 register XPVHV * const xhv = (XPVHV*)SvANY(PL_strtab);
2686 PERL_ARGS_ASSERT_SHARE_HEK_FLAGS;
2688 /* what follows is the moral equivalent of:
2690 if (!(Svp = hv_fetch(PL_strtab, str, len, FALSE)))
2691 hv_store(PL_strtab, str, len, NULL, hash);
2693 Can't rehash the shared string table, so not sure if it's worth
2694 counting the number of entries in the linked list
2697 /* assert(xhv_array != 0) */
2698 entry = (HvARRAY(PL_strtab))[hindex];
2699 for (;entry; entry = HeNEXT(entry)) {
2700 if (HeHASH(entry) != hash) /* strings can't be equal */
2702 if (HeKLEN(entry) != len)
2704 if (HeKEY(entry) != str && memNE(HeKEY(entry),str,len)) /* is this it? */
2706 if (HeKFLAGS(entry) != flags_masked)
2712 /* What used to be head of the list.
2713 If this is NULL, then we're the first entry for this slot, which
2714 means we need to increate fill. */
2715 struct shared_he *new_entry;
2718 HE **const head = &HvARRAY(PL_strtab)[hindex];
2719 HE *const next = *head;
2721 /* We don't actually store a HE from the arena and a regular HEK.
2722 Instead we allocate one chunk of memory big enough for both,
2723 and put the HEK straight after the HE. This way we can find the
2724 HEK directly from the HE.
2727 Newx(k, STRUCT_OFFSET(struct shared_he,
2728 shared_he_hek.hek_key[0]) + len + 2, char);
2729 new_entry = (struct shared_he *)k;
2730 entry = &(new_entry->shared_he_he);
2731 hek = &(new_entry->shared_he_hek);
2733 Copy(str, HEK_KEY(hek), len, char);
2734 HEK_KEY(hek)[len] = 0;
2736 HEK_HASH(hek) = hash;
2737 HEK_FLAGS(hek) = (unsigned char)flags_masked;
2739 /* Still "point" to the HEK, so that other code need not know what
2741 HeKEY_hek(entry) = hek;
2742 entry->he_valu.hent_refcount = 0;
2743 HeNEXT(entry) = next;
2746 xhv->xhv_keys++; /* HvTOTALKEYS(hv)++ */
2747 if (!next) { /* initial entry? */
2748 } else if (xhv->xhv_keys > xhv->xhv_max /* HvKEYS(hv) > HvMAX(hv) */) {
2753 ++entry->he_valu.hent_refcount;
2755 if (flags & HVhek_FREEKEY)
2758 return HeKEY_hek(entry);
2762 Perl_hv_placeholders_p(pTHX_ HV *hv)
2765 MAGIC *mg = mg_find((const SV *)hv, PERL_MAGIC_rhash);
2767 PERL_ARGS_ASSERT_HV_PLACEHOLDERS_P;
2770 mg = sv_magicext(MUTABLE_SV(hv), 0, PERL_MAGIC_rhash, 0, 0, 0);
2773 Perl_die(aTHX_ "panic: hv_placeholders_p");
2776 return &(mg->mg_len);
2781 Perl_hv_placeholders_get(pTHX_ const HV *hv)
2784 MAGIC * const mg = mg_find((const SV *)hv, PERL_MAGIC_rhash);
2786 PERL_ARGS_ASSERT_HV_PLACEHOLDERS_GET;
2788 return mg ? mg->mg_len : 0;
2792 Perl_hv_placeholders_set(pTHX_ HV *hv, I32 ph)
2795 MAGIC * const mg = mg_find((const SV *)hv, PERL_MAGIC_rhash);
2797 PERL_ARGS_ASSERT_HV_PLACEHOLDERS_SET;
2802 if (!sv_magicext(MUTABLE_SV(hv), 0, PERL_MAGIC_rhash, 0, 0, ph))
2803 Perl_die(aTHX_ "panic: hv_placeholders_set");
2805 /* else we don't need to add magic to record 0 placeholders. */
2809 S_refcounted_he_value(pTHX_ const struct refcounted_he *he)
2814 PERL_ARGS_ASSERT_REFCOUNTED_HE_VALUE;
2816 switch(he->refcounted_he_data[0] & HVrhek_typemask) {
2821 value = &PL_sv_placeholder;
2824 value = newSViv(he->refcounted_he_val.refcounted_he_u_iv);
2827 value = newSVuv(he->refcounted_he_val.refcounted_he_u_uv);
2830 case HVrhek_PV_UTF8:
2831 /* Create a string SV that directly points to the bytes in our
2833 value = newSV_type(SVt_PV);
2834 SvPV_set(value, (char *) he->refcounted_he_data + 1);
2835 SvCUR_set(value, he->refcounted_he_val.refcounted_he_u_len);
2836 /* This stops anything trying to free it */
2837 SvLEN_set(value, 0);
2839 SvREADONLY_on(value);
2840 if ((he->refcounted_he_data[0] & HVrhek_typemask) == HVrhek_PV_UTF8)
2844 Perl_croak(aTHX_ "panic: refcounted_he_value bad flags %"UVxf,
2845 (UV)he->refcounted_he_data[0]);
2851 =for apidoc m|HV *|refcounted_he_chain_2hv|const struct refcounted_he *c|U32 flags
2853 Generates and returns a C<HV *> representing the content of a
2854 C<refcounted_he> chain.
2855 I<flags> is currently unused and must be zero.
2860 Perl_refcounted_he_chain_2hv(pTHX_ const struct refcounted_he *chain, U32 flags)
2864 U32 placeholders, max;
2867 Perl_croak(aTHX_ "panic: refcounted_he_chain_2hv bad flags %"UVxf,
2870 /* We could chase the chain once to get an idea of the number of keys,
2871 and call ksplit. But for now we'll make a potentially inefficient
2872 hash with only 8 entries in its array. */
2877 Newxz(array, PERL_HV_ARRAY_ALLOC_BYTES(max + 1), char);
2878 HvARRAY(hv) = (HE**)array;
2884 U32 hash = chain->refcounted_he_hash;
2886 U32 hash = HEK_HASH(chain->refcounted_he_hek);
2888 HE **oentry = &((HvARRAY(hv))[hash & max]);
2889 HE *entry = *oentry;
2892 for (; entry; entry = HeNEXT(entry)) {
2893 if (HeHASH(entry) == hash) {
2894 /* We might have a duplicate key here. If so, entry is older
2895 than the key we've already put in the hash, so if they are
2896 the same, skip adding entry. */
2898 const STRLEN klen = HeKLEN(entry);
2899 const char *const key = HeKEY(entry);
2900 if (klen == chain->refcounted_he_keylen
2901 && (!!HeKUTF8(entry)
2902 == !!(chain->refcounted_he_data[0] & HVhek_UTF8))
2903 && memEQ(key, REF_HE_KEY(chain), klen))
2906 if (HeKEY_hek(entry) == chain->refcounted_he_hek)
2908 if (HeKLEN(entry) == HEK_LEN(chain->refcounted_he_hek)
2909 && HeKUTF8(entry) == HEK_UTF8(chain->refcounted_he_hek)
2910 && memEQ(HeKEY(entry), HEK_KEY(chain->refcounted_he_hek),
2921 = share_hek_flags(REF_HE_KEY(chain),
2922 chain->refcounted_he_keylen,
2923 chain->refcounted_he_hash,
2924 (chain->refcounted_he_data[0]
2925 & (HVhek_UTF8|HVhek_WASUTF8)));
2927 HeKEY_hek(entry) = share_hek_hek(chain->refcounted_he_hek);
2929 value = refcounted_he_value(chain);
2930 if (value == &PL_sv_placeholder)
2932 HeVAL(entry) = value;
2934 /* Link it into the chain. */
2935 HeNEXT(entry) = *oentry;
2941 chain = chain->refcounted_he_next;
2945 clear_placeholders(hv, placeholders);
2946 HvTOTALKEYS(hv) -= placeholders;
2949 /* We could check in the loop to see if we encounter any keys with key
2950 flags, but it's probably not worth it, as this per-hash flag is only
2951 really meant as an optimisation for things like Storable. */
2953 DEBUG_A(Perl_hv_assert(aTHX_ hv));
2959 =for apidoc m|SV *|refcounted_he_fetch_pvn|const struct refcounted_he *chain|const char *keypv|STRLEN keylen|U32 hash|U32 flags
2961 Search along a C<refcounted_he> chain for an entry with the key specified
2962 by I<keypv> and I<keylen>. If I<flags> has the C<REFCOUNTED_HE_KEY_UTF8>
2963 bit set, the key octets are interpreted as UTF-8, otherwise they
2964 are interpreted as Latin-1. I<hash> is a precomputed hash of the key
2965 string, or zero if it has not been precomputed. Returns a mortal scalar
2966 representing the value associated with the key, or C<&PL_sv_placeholder>
2967 if there is no value associated with the key.
2973 Perl_refcounted_he_fetch_pvn(pTHX_ const struct refcounted_he *chain,
2974 const char *keypv, STRLEN keylen, U32 hash, U32 flags)
2978 PERL_ARGS_ASSERT_REFCOUNTED_HE_FETCH_PVN;
2980 if (flags & ~REFCOUNTED_HE_KEY_UTF8)
2981 Perl_croak(aTHX_ "panic: refcounted_he_fetch_pvn bad flags %"UVxf,
2984 return &PL_sv_placeholder;
2985 if (flags & REFCOUNTED_HE_KEY_UTF8) {
2986 /* For searching purposes, canonicalise to Latin-1 where possible. */
2987 const char *keyend = keypv + keylen, *p;
2988 STRLEN nonascii_count = 0;
2989 for (p = keypv; p != keyend; p++) {
2992 if (!((c & 0xfe) == 0xc2 && ++p != keyend &&
2993 (((U8)*p) & 0xc0) == 0x80))
2994 goto canonicalised_key;
2998 if (nonascii_count) {
3000 const char *p = keypv, *keyend = keypv + keylen;
3001 keylen -= nonascii_count;
3002 Newx(q, keylen, char);
3005 for (; p != keyend; p++, q++) {
3008 ((c & 0x80) ? ((c & 0x03) << 6) | (((U8)*++p) & 0x3f) : c);
3011 flags &= ~REFCOUNTED_HE_KEY_UTF8;
3012 canonicalised_key: ;
3014 utf8_flag = (flags & REFCOUNTED_HE_KEY_UTF8) ? HVhek_UTF8 : 0;
3016 PERL_HASH(hash, keypv, keylen);
3018 for (; chain; chain = chain->refcounted_he_next) {
3021 hash == chain->refcounted_he_hash &&
3022 keylen == chain->refcounted_he_keylen &&
3023 memEQ(REF_HE_KEY(chain), keypv, keylen) &&
3024 utf8_flag == (chain->refcounted_he_data[0] & HVhek_UTF8)
3026 hash == HEK_HASH(chain->refcounted_he_hek) &&
3027 keylen == (STRLEN)HEK_LEN(chain->refcounted_he_hek) &&
3028 memEQ(HEK_KEY(chain->refcounted_he_hek), keypv, keylen) &&
3029 utf8_flag == (HEK_FLAGS(chain->refcounted_he_hek) & HVhek_UTF8)
3032 return sv_2mortal(refcounted_he_value(chain));
3034 return &PL_sv_placeholder;
3038 =for apidoc m|SV *|refcounted_he_fetch_pv|const struct refcounted_he *chain|const char *key|U32 hash|U32 flags
3040 Like L</refcounted_he_fetch_pvn>, but takes a nul-terminated string
3041 instead of a string/length pair.
3047 Perl_refcounted_he_fetch_pv(pTHX_ const struct refcounted_he *chain,
3048 const char *key, U32 hash, U32 flags)
3050 PERL_ARGS_ASSERT_REFCOUNTED_HE_FETCH_PV;
3051 return refcounted_he_fetch_pvn(chain, key, strlen(key), hash, flags);
3055 =for apidoc m|SV *|refcounted_he_fetch_sv|const struct refcounted_he *chain|SV *key|U32 hash|U32 flags
3057 Like L</refcounted_he_fetch_pvn>, but takes a Perl scalar instead of a
3064 Perl_refcounted_he_fetch_sv(pTHX_ const struct refcounted_he *chain,
3065 SV *key, U32 hash, U32 flags)
3069 PERL_ARGS_ASSERT_REFCOUNTED_HE_FETCH_SV;
3070 if (flags & REFCOUNTED_HE_KEY_UTF8)
3071 Perl_croak(aTHX_ "panic: refcounted_he_fetch_sv bad flags %"UVxf,
3073 keypv = SvPV_const(key, keylen);
3075 flags |= REFCOUNTED_HE_KEY_UTF8;
3076 if (!hash && SvIsCOW_shared_hash(key))
3077 hash = SvSHARED_HASH(key);
3078 return refcounted_he_fetch_pvn(chain, keypv, keylen, hash, flags);
3082 =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
3084 Creates a new C<refcounted_he>. This consists of a single key/value
3085 pair and a reference to an existing C<refcounted_he> chain (which may
3086 be empty), and thus forms a longer chain. When using the longer chain,
3087 the new key/value pair takes precedence over any entry for the same key
3088 further along the chain.
3090 The new key is specified by I<keypv> and I<keylen>. If I<flags> has
3091 the C<REFCOUNTED_HE_KEY_UTF8> bit set, the key octets are interpreted
3092 as UTF-8, otherwise they are interpreted as Latin-1. I<hash> is
3093 a precomputed hash of the key string, or zero if it has not been
3096 I<value> is the scalar value to store for this key. I<value> is copied
3097 by this function, which thus does not take ownership of any reference
3098 to it, and later changes to the scalar will not be reflected in the
3099 value visible in the C<refcounted_he>. Complex types of scalar will not
3100 be stored with referential integrity, but will be coerced to strings.
3101 I<value> may be either null or C<&PL_sv_placeholder> to indicate that no
3102 value is to be associated with the key; this, as with any non-null value,
3103 takes precedence over the existence of a value for the key further along
3106 I<parent> points to the rest of the C<refcounted_he> chain to be
3107 attached to the new C<refcounted_he>. This function takes ownership
3108 of one reference to I<parent>, and returns one reference to the new
3114 struct refcounted_he *
3115 Perl_refcounted_he_new_pvn(pTHX_ struct refcounted_he *parent,
3116 const char *keypv, STRLEN keylen, U32 hash, SV *value, U32 flags)
3119 STRLEN value_len = 0;
3120 const char *value_p = NULL;
3124 STRLEN key_offset = 1;
3125 struct refcounted_he *he;
3126 PERL_ARGS_ASSERT_REFCOUNTED_HE_NEW_PVN;
3128 if (!value || value == &PL_sv_placeholder) {
3129 value_type = HVrhek_delete;
3130 } else if (SvPOK(value)) {
3131 value_type = HVrhek_PV;
3132 } else if (SvIOK(value)) {
3133 value_type = SvUOK((const SV *)value) ? HVrhek_UV : HVrhek_IV;
3134 } else if (!SvOK(value)) {
3135 value_type = HVrhek_undef;
3137 value_type = HVrhek_PV;
3139 is_pv = value_type == HVrhek_PV;
3141 /* Do it this way so that the SvUTF8() test is after the SvPV, in case
3142 the value is overloaded, and doesn't yet have the UTF-8flag set. */
3143 value_p = SvPV_const(value, value_len);
3145 value_type = HVrhek_PV_UTF8;
3146 key_offset = value_len + 2;
3148 hekflags = value_type;
3150 if (flags & REFCOUNTED_HE_KEY_UTF8) {
3151 /* Canonicalise to Latin-1 where possible. */
3152 const char *keyend = keypv + keylen, *p;
3153 STRLEN nonascii_count = 0;
3154 for (p = keypv; p != keyend; p++) {
3157 if (!((c & 0xfe) == 0xc2 && ++p != keyend &&
3158 (((U8)*p) & 0xc0) == 0x80))
3159 goto canonicalised_key;
3163 if (nonascii_count) {
3165 const char *p = keypv, *keyend = keypv + keylen;
3166 keylen -= nonascii_count;
3167 Newx(q, keylen, char);
3170 for (; p != keyend; p++, q++) {
3173 ((c & 0x80) ? ((c & 0x03) << 6) | (((U8)*++p) & 0x3f) : c);
3176 flags &= ~REFCOUNTED_HE_KEY_UTF8;
3177 canonicalised_key: ;
3179 if (flags & REFCOUNTED_HE_KEY_UTF8)
3180 hekflags |= HVhek_UTF8;
3182 PERL_HASH(hash, keypv, keylen);
3185 he = (struct refcounted_he*)
3186 PerlMemShared_malloc(sizeof(struct refcounted_he) - 1
3190 he = (struct refcounted_he*)
3191 PerlMemShared_malloc(sizeof(struct refcounted_he) - 1
3195 he->refcounted_he_next = parent;
3198 Copy(value_p, he->refcounted_he_data + 1, value_len + 1, char);
3199 he->refcounted_he_val.refcounted_he_u_len = value_len;
3200 } else if (value_type == HVrhek_IV) {
3201 he->refcounted_he_val.refcounted_he_u_iv = SvIVX(value);
3202 } else if (value_type == HVrhek_UV) {
3203 he->refcounted_he_val.refcounted_he_u_uv = SvUVX(value);
3207 he->refcounted_he_hash = hash;
3208 he->refcounted_he_keylen = keylen;
3209 Copy(keypv, he->refcounted_he_data + key_offset, keylen, char);
3211 he->refcounted_he_hek = share_hek_flags(keypv, keylen, hash, hekflags);
3214 he->refcounted_he_data[0] = hekflags;
3215 he->refcounted_he_refcnt = 1;
3221 =for apidoc m|struct refcounted_he *|refcounted_he_new_pv|struct refcounted_he *parent|const char *key|U32 hash|SV *value|U32 flags
3223 Like L</refcounted_he_new_pvn>, but takes a nul-terminated string instead
3224 of a string/length pair.
3229 struct refcounted_he *
3230 Perl_refcounted_he_new_pv(pTHX_ struct refcounted_he *parent,
3231 const char *key, U32 hash, SV *value, U32 flags)
3233 PERL_ARGS_ASSERT_REFCOUNTED_HE_NEW_PV;
3234 return refcounted_he_new_pvn(parent, key, strlen(key), hash, value, flags);
3238 =for apidoc m|struct refcounted_he *|refcounted_he_new_sv|struct refcounted_he *parent|SV *key|U32 hash|SV *value|U32 flags
3240 Like L</refcounted_he_new_pvn>, but takes a Perl scalar instead of a
3246 struct refcounted_he *
3247 Perl_refcounted_he_new_sv(pTHX_ struct refcounted_he *parent,
3248 SV *key, U32 hash, SV *value, U32 flags)
3252 PERL_ARGS_ASSERT_REFCOUNTED_HE_NEW_SV;
3253 if (flags & REFCOUNTED_HE_KEY_UTF8)
3254 Perl_croak(aTHX_ "panic: refcounted_he_new_sv bad flags %"UVxf,
3256 keypv = SvPV_const(key, keylen);
3258 flags |= REFCOUNTED_HE_KEY_UTF8;
3259 if (!hash && SvIsCOW_shared_hash(key))
3260 hash = SvSHARED_HASH(key);
3261 return refcounted_he_new_pvn(parent, keypv, keylen, hash, value, flags);
3265 =for apidoc m|void|refcounted_he_free|struct refcounted_he *he
3267 Decrements the reference count of a C<refcounted_he> by one. If the
3268 reference count reaches zero the structure's memory is freed, which
3269 (recursively) causes a reduction of its parent C<refcounted_he>'s
3270 reference count. It is safe to pass a null pointer to this function:
3271 no action occurs in this case.
3277 Perl_refcounted_he_free(pTHX_ struct refcounted_he *he) {
3279 PERL_UNUSED_CONTEXT;
3282 struct refcounted_he *copy;
3286 new_count = --he->refcounted_he_refcnt;
3287 HINTS_REFCNT_UNLOCK;
3293 #ifndef USE_ITHREADS
3294 unshare_hek_or_pvn (he->refcounted_he_hek, 0, 0, 0);
3297 he = he->refcounted_he_next;
3298 PerlMemShared_free(copy);
3303 =for apidoc m|struct refcounted_he *|refcounted_he_inc|struct refcounted_he *he
3305 Increment the reference count of a C<refcounted_he>. The pointer to the
3306 C<refcounted_he> is also returned. It is safe to pass a null pointer
3307 to this function: no action occurs and a null pointer is returned.
3312 struct refcounted_he *
3313 Perl_refcounted_he_inc(pTHX_ struct refcounted_he *he)
3317 he->refcounted_he_refcnt++;
3318 HINTS_REFCNT_UNLOCK;
3323 /* pp_entereval is aware that labels are stored with a key ':' at the top of
3326 Perl_fetch_cop_label(pTHX_ COP *const cop, STRLEN *len, U32 *flags) {
3327 struct refcounted_he *const chain = cop->cop_hints_hash;
3329 PERL_ARGS_ASSERT_FETCH_COP_LABEL;
3334 if (chain->refcounted_he_keylen != 1)
3336 if (*REF_HE_KEY(chain) != ':')
3339 if ((STRLEN)HEK_LEN(chain->refcounted_he_hek) != 1)
3341 if (*HEK_KEY(chain->refcounted_he_hek) != ':')
3344 /* Stop anyone trying to really mess us up by adding their own value for
3346 if ((chain->refcounted_he_data[0] & HVrhek_typemask) != HVrhek_PV
3347 && (chain->refcounted_he_data[0] & HVrhek_typemask) != HVrhek_PV_UTF8)
3351 *len = chain->refcounted_he_val.refcounted_he_u_len;
3353 *flags = ((chain->refcounted_he_data[0] & HVrhek_typemask)
3354 == HVrhek_PV_UTF8) ? SVf_UTF8 : 0;
3356 return chain->refcounted_he_data + 1;
3360 Perl_store_cop_label(pTHX_ COP *const cop, const char *label, STRLEN len,
3364 PERL_ARGS_ASSERT_STORE_COP_LABEL;
3366 if (flags & ~(SVf_UTF8))
3367 Perl_croak(aTHX_ "panic: store_cop_label illegal flag bits 0x%" UVxf,
3369 labelsv = sv_2mortal(newSVpvn(label, len));
3370 if (flags & SVf_UTF8)
3373 = refcounted_he_new_pvs(cop->cop_hints_hash, ":", labelsv, 0);
3377 =for apidoc hv_assert
3379 Check that a hash is in an internally consistent state.
3387 Perl_hv_assert(pTHX_ HV *hv)
3392 int placeholders = 0;
3395 const I32 riter = HvRITER_get(hv);
3396 HE *eiter = HvEITER_get(hv);
3398 PERL_ARGS_ASSERT_HV_ASSERT;
3400 (void)hv_iterinit(hv);
3402 while ((entry = hv_iternext_flags(hv, HV_ITERNEXT_WANTPLACEHOLDERS))) {
3403 /* sanity check the values */
3404 if (HeVAL(entry) == &PL_sv_placeholder)
3408 /* sanity check the keys */
3409 if (HeSVKEY(entry)) {
3410 NOOP; /* Don't know what to check on SV keys. */
3411 } else if (HeKUTF8(entry)) {
3413 if (HeKWASUTF8(entry)) {
3414 PerlIO_printf(Perl_debug_log,
3415 "hash key has both WASUTF8 and UTF8: '%.*s'\n",
3416 (int) HeKLEN(entry), HeKEY(entry));
3419 } else if (HeKWASUTF8(entry))
3422 if (!SvTIED_mg((const SV *)hv, PERL_MAGIC_tied)) {
3423 static const char bad_count[] = "Count %d %s(s), but hash reports %d\n";
3424 const int nhashkeys = HvUSEDKEYS(hv);
3425 const int nhashplaceholders = HvPLACEHOLDERS_get(hv);
3427 if (nhashkeys != real) {
3428 PerlIO_printf(Perl_debug_log, bad_count, real, "keys", nhashkeys );
3431 if (nhashplaceholders != placeholders) {
3432 PerlIO_printf(Perl_debug_log, bad_count, placeholders, "placeholder", nhashplaceholders );
3436 if (withflags && ! HvHASKFLAGS(hv)) {
3437 PerlIO_printf(Perl_debug_log,
3438 "Hash has HASKFLAGS off but I count %d key(s) with flags\n",
3443 sv_dump(MUTABLE_SV(hv));
3445 HvRITER_set(hv, riter); /* Restore hash iterator state */
3446 HvEITER_set(hv, eiter);
3453 * c-indentation-style: bsd
3455 * indent-tabs-mode: t
3458 * ex: set ts=8 sts=4 sw=4 noet: