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 */
991 const char *name = NULL;
995 if (HeHASH(entry) != hash) /* strings can't be equal */
997 if (HeKLEN(entry) != (I32)klen)
999 if (HeKEY(entry) != key && memNE(HeKEY(entry),key,klen)) /* is this it? */
1001 if ((HeKFLAGS(entry) ^ masked_flags) & HVhek_UTF8)
1004 if (hv == PL_strtab) {
1005 if (k_flags & HVhek_FREEKEY)
1007 Perl_croak(aTHX_ S_strtab_error, "delete");
1010 /* if placeholder is here, it's already been deleted.... */
1011 if (HeVAL(entry) == &PL_sv_placeholder) {
1012 if (k_flags & HVhek_FREEKEY)
1016 if (SvREADONLY(hv) && HeVAL(entry) && SvREADONLY(HeVAL(entry))) {
1017 hv_notallowed(k_flags, key, klen,
1018 "Attempt to delete readonly key '%"SVf"' from"
1019 " a restricted hash");
1021 if (k_flags & HVhek_FREEKEY)
1024 /* If this is a stash and the key ends with ::, then someone is
1025 * deleting a package.
1026 * Check whether the gv (HeVAL(entry)) is still in the symbol
1027 * table and then save the name to pass to mro_package_moved after
1029 * We cannot pass the gv to mro_package_moved directly, as that
1030 * function also checks whether the gv is to be found at the loca-
1031 * tion its name indicates, which will no longer be the case once
1032 * this element is deleted. So we have to do that check here.
1034 if (HeVAL(entry) && HvENAME_get(hv)) {
1036 if (keysv) key = SvPV(keysv, klen);
1037 if (klen > 1 && key[klen-2] == ':' && key[klen-1] == ':'
1038 && (klen != 6 || hv!=PL_defstash || memNE(key,"main::",6))
1039 && SvTYPE(sv) == SVt_PVGV && (stash = GvHV((GV *)sv))
1040 && HvENAME_get(stash)) {
1041 SV * const namesv = sv_newmortal();
1042 gv_fullname4(namesv, (GV *)sv, NULL, 0);
1044 gv_fetchsv(namesv, GV_NOADD_NOINIT, SVt_PVGV)
1048 name = SvPV_const(namesv, namlen);
1049 namlen -= 2; /* skip trailing :: */
1050 /* Hang on to it for a bit. */
1051 SvREFCNT_inc_simple_void_NN(
1052 sv_2mortal((SV *)stash)
1056 else if (klen == 3 && strnEQ(key, "ISA", 3))
1060 if (d_flags & G_DISCARD)
1063 sv = sv_2mortal(HeVAL(entry));
1064 HeVAL(entry) = &PL_sv_placeholder;
1068 * If a restricted hash, rather than really deleting the entry, put
1069 * a placeholder there. This marks the key as being "approved", so
1070 * we can still access via not-really-existing key without raising
1073 if (SvREADONLY(hv)) {
1074 SvREFCNT_dec(HeVAL(entry));
1075 HeVAL(entry) = &PL_sv_placeholder;
1076 /* We'll be saving this slot, so the number of allocated keys
1077 * doesn't go down, but the number placeholders goes up */
1078 HvPLACEHOLDERS(hv)++;
1080 *oentry = HeNEXT(entry);
1081 if (SvOOK(hv) && entry == HvAUX(hv)->xhv_eiter /* HvEITER(hv) */)
1084 hv_free_ent(hv, entry);
1085 xhv->xhv_keys--; /* HvTOTALKEYS(hv)-- */
1086 if (xhv->xhv_keys == 0)
1087 HvHASKFLAGS_off(hv);
1090 if (mro_changes == 1) mro_isa_changed_in(hv);
1091 else if (mro_changes == 2)
1092 mro_package_moved(NULL, stash, NULL, name, namlen);
1096 if (SvREADONLY(hv)) {
1097 hv_notallowed(k_flags, key, klen,
1098 "Attempt to delete disallowed key '%"SVf"' from"
1099 " a restricted hash");
1102 if (k_flags & HVhek_FREEKEY)
1108 S_hsplit(pTHX_ HV *hv)
1111 register XPVHV* const xhv = (XPVHV*)SvANY(hv);
1112 const I32 oldsize = (I32) xhv->xhv_max+1; /* HvMAX(hv)+1 (sick) */
1113 register I32 newsize = oldsize * 2;
1115 char *a = (char*) HvARRAY(hv);
1117 int longest_chain = 0;
1120 PERL_ARGS_ASSERT_HSPLIT;
1122 /*PerlIO_printf(PerlIO_stderr(), "hsplit called for %p which had %d\n",
1123 (void*)hv, (int) oldsize);*/
1125 if (HvPLACEHOLDERS_get(hv) && !SvREADONLY(hv)) {
1126 /* Can make this clear any placeholders first for non-restricted hashes,
1127 even though Storable rebuilds restricted hashes by putting in all the
1128 placeholders (first) before turning on the readonly flag, because
1129 Storable always pre-splits the hash. */
1130 hv_clear_placeholders(hv);
1134 #if defined(STRANGE_MALLOC) || defined(MYMALLOC)
1135 Renew(a, PERL_HV_ARRAY_ALLOC_BYTES(newsize)
1136 + (SvOOK(hv) ? sizeof(struct xpvhv_aux) : 0), char);
1142 Move(&a[oldsize * sizeof(HE*)], &a[newsize * sizeof(HE*)], 1, struct xpvhv_aux);
1145 Newx(a, PERL_HV_ARRAY_ALLOC_BYTES(newsize)
1146 + (SvOOK(hv) ? sizeof(struct xpvhv_aux) : 0), char);
1151 Copy(HvARRAY(hv), a, oldsize * sizeof(HE*), char);
1153 Copy(HvAUX(hv), &a[newsize * sizeof(HE*)], 1, struct xpvhv_aux);
1155 Safefree(HvARRAY(hv));
1159 Zero(&a[oldsize * sizeof(HE*)], (newsize-oldsize) * sizeof(HE*), char); /* zero 2nd half*/
1160 xhv->xhv_max = --newsize; /* HvMAX(hv) = --newsize */
1161 HvARRAY(hv) = (HE**) a;
1164 for (i=0; i<oldsize; i++,aep++) {
1165 int left_length = 0;
1166 int right_length = 0;
1171 if (!entry) /* non-existent */
1175 if ((HeHASH(entry) & newsize) != (U32)i) {
1176 *oentry = HeNEXT(entry);
1177 HeNEXT(entry) = *bep;
1182 oentry = &HeNEXT(entry);
1187 /* I think we don't actually need to keep track of the longest length,
1188 merely flag if anything is too long. But for the moment while
1189 developing this code I'll track it. */
1190 if (left_length > longest_chain)
1191 longest_chain = left_length;
1192 if (right_length > longest_chain)
1193 longest_chain = right_length;
1197 /* Pick your policy for "hashing isn't working" here: */
1198 if (longest_chain <= HV_MAX_LENGTH_BEFORE_SPLIT /* split worked? */
1203 if (hv == PL_strtab) {
1204 /* Urg. Someone is doing something nasty to the string table.
1209 /* Awooga. Awooga. Pathological data. */
1210 /*PerlIO_printf(PerlIO_stderr(), "%p %d of %d with %d/%d buckets\n", (void*)hv,
1211 longest_chain, HvTOTALKEYS(hv), HvFILL(hv), 1+HvMAX(hv));*/
1214 Newxz(a, PERL_HV_ARRAY_ALLOC_BYTES(newsize)
1215 + (SvOOK(hv) ? sizeof(struct xpvhv_aux) : 0), char);
1217 Copy(HvAUX(hv), &a[newsize * sizeof(HE*)], 1, struct xpvhv_aux);
1220 was_shared = HvSHAREKEYS(hv);
1222 HvSHAREKEYS_off(hv);
1227 for (i=0; i<newsize; i++,aep++) {
1228 register HE *entry = *aep;
1230 /* We're going to trash this HE's next pointer when we chain it
1231 into the new hash below, so store where we go next. */
1232 HE * const next = HeNEXT(entry);
1237 PERL_HASH_INTERNAL(hash, HeKEY(entry), HeKLEN(entry));
1242 = save_hek_flags(HeKEY(entry), HeKLEN(entry),
1243 hash, HeKFLAGS(entry));
1244 unshare_hek (HeKEY_hek(entry));
1245 HeKEY_hek(entry) = new_hek;
1247 /* Not shared, so simply write the new hash in. */
1248 HeHASH(entry) = hash;
1250 /*PerlIO_printf(PerlIO_stderr(), "%d ", HeKFLAGS(entry));*/
1251 HEK_REHASH_on(HeKEY_hek(entry));
1252 /*PerlIO_printf(PerlIO_stderr(), "%d\n", HeKFLAGS(entry));*/
1254 /* Copy oentry to the correct new chain. */
1255 bep = ((HE**)a) + (hash & (I32) xhv->xhv_max);
1256 HeNEXT(entry) = *bep;
1262 Safefree (HvARRAY(hv));
1263 HvARRAY(hv) = (HE **)a;
1267 Perl_hv_ksplit(pTHX_ HV *hv, IV newmax)
1270 register XPVHV* xhv = (XPVHV*)SvANY(hv);
1271 const I32 oldsize = (I32) xhv->xhv_max+1; /* HvMAX(hv)+1 (sick) */
1272 register I32 newsize;
1277 PERL_ARGS_ASSERT_HV_KSPLIT;
1279 newsize = (I32) newmax; /* possible truncation here */
1280 if (newsize != newmax || newmax <= oldsize)
1282 while ((newsize & (1 + ~newsize)) != newsize) {
1283 newsize &= ~(newsize & (1 + ~newsize)); /* get proper power of 2 */
1285 if (newsize < newmax)
1287 if (newsize < newmax)
1288 return; /* overflow detection */
1290 a = (char *) HvARRAY(hv);
1293 #if defined(STRANGE_MALLOC) || defined(MYMALLOC)
1294 Renew(a, PERL_HV_ARRAY_ALLOC_BYTES(newsize)
1295 + (SvOOK(hv) ? sizeof(struct xpvhv_aux) : 0), char);
1301 Copy(&a[oldsize * sizeof(HE*)], &a[newsize * sizeof(HE*)], 1, struct xpvhv_aux);
1304 Newx(a, PERL_HV_ARRAY_ALLOC_BYTES(newsize)
1305 + (SvOOK(hv) ? sizeof(struct xpvhv_aux) : 0), char);
1310 Copy(HvARRAY(hv), a, oldsize * sizeof(HE*), char);
1312 Copy(HvAUX(hv), &a[newsize * sizeof(HE*)], 1, struct xpvhv_aux);
1314 Safefree(HvARRAY(hv));
1317 Zero(&a[oldsize * sizeof(HE*)], (newsize-oldsize) * sizeof(HE*), char); /* zero 2nd half*/
1320 Newxz(a, PERL_HV_ARRAY_ALLOC_BYTES(newsize), char);
1322 xhv->xhv_max = --newsize; /* HvMAX(hv) = --newsize */
1323 HvARRAY(hv) = (HE **) a;
1324 if (!xhv->xhv_keys /* !HvTOTALKEYS(hv) */) /* skip rest if no entries */
1328 for (i=0; i<oldsize; i++,aep++) {
1332 if (!entry) /* non-existent */
1335 register I32 j = (HeHASH(entry) & newsize);
1339 *oentry = HeNEXT(entry);
1340 HeNEXT(entry) = aep[j];
1344 oentry = &HeNEXT(entry);
1351 Perl_newHVhv(pTHX_ HV *ohv)
1354 HV * const hv = newHV();
1357 if (!ohv || !HvTOTALKEYS(ohv))
1359 hv_max = HvMAX(ohv);
1361 if (!SvMAGICAL((const SV *)ohv)) {
1362 /* It's an ordinary hash, so copy it fast. AMS 20010804 */
1364 const bool shared = !!HvSHAREKEYS(ohv);
1365 HE **ents, ** const oents = (HE **)HvARRAY(ohv);
1367 Newx(a, PERL_HV_ARRAY_ALLOC_BYTES(hv_max+1), char);
1370 /* In each bucket... */
1371 for (i = 0; i <= hv_max; i++) {
1373 HE *oent = oents[i];
1380 /* Copy the linked list of entries. */
1381 for (; oent; oent = HeNEXT(oent)) {
1382 const U32 hash = HeHASH(oent);
1383 const char * const key = HeKEY(oent);
1384 const STRLEN len = HeKLEN(oent);
1385 const int flags = HeKFLAGS(oent);
1386 HE * const ent = new_HE();
1387 SV *const val = HeVAL(oent);
1389 HeVAL(ent) = SvIMMORTAL(val) ? val : newSVsv(val);
1391 = shared ? share_hek_flags(key, len, hash, flags)
1392 : save_hek_flags(key, len, hash, flags);
1403 HvTOTALKEYS(hv) = HvTOTALKEYS(ohv);
1407 /* Iterate over ohv, copying keys and values one at a time. */
1409 const I32 riter = HvRITER_get(ohv);
1410 HE * const eiter = HvEITER_get(ohv);
1411 STRLEN hv_fill = HvFILL(ohv);
1413 /* Can we use fewer buckets? (hv_max is always 2^n-1) */
1414 while (hv_max && hv_max + 1 >= hv_fill * 2)
1415 hv_max = hv_max / 2;
1419 while ((entry = hv_iternext_flags(ohv, 0))) {
1420 SV *const val = HeVAL(entry);
1421 (void)hv_store_flags(hv, HeKEY(entry), HeKLEN(entry),
1422 SvIMMORTAL(val) ? val : newSVsv(val),
1423 HeHASH(entry), HeKFLAGS(entry));
1425 HvRITER_set(ohv, riter);
1426 HvEITER_set(ohv, eiter);
1433 =for apidoc Am|HV *|hv_copy_hints_hv|HV *ohv
1435 A specialised version of L</newHVhv> for copying C<%^H>. I<ohv> must be
1436 a pointer to a hash (which may have C<%^H> magic, but should be generally
1437 non-magical), or C<NULL> (interpreted as an empty hash). The content
1438 of I<ohv> is copied to a new hash, which has the C<%^H>-specific magic
1439 added to it. A pointer to the new hash is returned.
1445 Perl_hv_copy_hints_hv(pTHX_ HV *const ohv)
1447 HV * const hv = newHV();
1449 if (ohv && HvTOTALKEYS(ohv)) {
1450 STRLEN hv_max = HvMAX(ohv);
1451 STRLEN hv_fill = HvFILL(ohv);
1453 const I32 riter = HvRITER_get(ohv);
1454 HE * const eiter = HvEITER_get(ohv);
1456 while (hv_max && hv_max + 1 >= hv_fill * 2)
1457 hv_max = hv_max / 2;
1461 while ((entry = hv_iternext_flags(ohv, 0))) {
1462 SV *const sv = newSVsv(HeVAL(entry));
1463 SV *heksv = newSVhek(HeKEY_hek(entry));
1464 sv_magic(sv, NULL, PERL_MAGIC_hintselem,
1465 (char *)heksv, HEf_SVKEY);
1466 SvREFCNT_dec(heksv);
1467 (void)hv_store_flags(hv, HeKEY(entry), HeKLEN(entry),
1468 sv, HeHASH(entry), HeKFLAGS(entry));
1470 HvRITER_set(ohv, riter);
1471 HvEITER_set(ohv, eiter);
1473 hv_magic(hv, NULL, PERL_MAGIC_hints);
1478 Perl_hv_free_ent(pTHX_ HV *hv, register HE *entry)
1483 PERL_ARGS_ASSERT_HV_FREE_ENT;
1488 if (val && isGV(val) && isGV_with_GP(val) && GvCVu(val) && HvENAME(hv))
1489 mro_method_changed_in(hv); /* deletion of method from stash */
1491 if (HeKLEN(entry) == HEf_SVKEY) {
1492 SvREFCNT_dec(HeKEY_sv(entry));
1493 Safefree(HeKEY_hek(entry));
1495 else if (HvSHAREKEYS(hv))
1496 unshare_hek(HeKEY_hek(entry));
1498 Safefree(HeKEY_hek(entry));
1504 Perl_hv_delayfree_ent(pTHX_ HV *hv, register HE *entry)
1508 PERL_ARGS_ASSERT_HV_DELAYFREE_ENT;
1512 /* SvREFCNT_inc to counter the SvREFCNT_dec in hv_free_ent */
1513 sv_2mortal(SvREFCNT_inc(HeVAL(entry))); /* free between statements */
1514 if (HeKLEN(entry) == HEf_SVKEY) {
1515 sv_2mortal(SvREFCNT_inc(HeKEY_sv(entry)));
1517 hv_free_ent(hv, entry);
1521 =for apidoc hv_clear
1523 Clears a hash, making it empty.
1529 Perl_hv_clear(pTHX_ HV *hv)
1532 register XPVHV* xhv;
1536 DEBUG_A(Perl_hv_assert(aTHX_ hv));
1538 xhv = (XPVHV*)SvANY(hv);
1540 if (SvREADONLY(hv) && HvARRAY(hv) != NULL) {
1541 /* restricted hash: convert all keys to placeholders */
1543 for (i = 0; i <= xhv->xhv_max; i++) {
1544 HE *entry = (HvARRAY(hv))[i];
1545 for (; entry; entry = HeNEXT(entry)) {
1546 /* not already placeholder */
1547 if (HeVAL(entry) != &PL_sv_placeholder) {
1548 if (HeVAL(entry) && SvREADONLY(HeVAL(entry))) {
1549 SV* const keysv = hv_iterkeysv(entry);
1551 "Attempt to delete readonly key '%"SVf"' from a restricted hash",
1554 SvREFCNT_dec(HeVAL(entry));
1555 HeVAL(entry) = &PL_sv_placeholder;
1556 HvPLACEHOLDERS(hv)++;
1564 HvPLACEHOLDERS_set(hv, 0);
1566 Zero(HvARRAY(hv), xhv->xhv_max+1 /* HvMAX(hv)+1 */, HE*);
1569 mg_clear(MUTABLE_SV(hv));
1571 HvHASKFLAGS_off(hv);
1576 mro_isa_changed_in(hv);
1577 HvEITER_set(hv, NULL);
1582 =for apidoc hv_clear_placeholders
1584 Clears any placeholders from a hash. If a restricted hash has any of its keys
1585 marked as readonly and the key is subsequently deleted, the key is not actually
1586 deleted but is marked by assigning it a value of &PL_sv_placeholder. This tags
1587 it so it will be ignored by future operations such as iterating over the hash,
1588 but will still allow the hash to have a value reassigned to the key at some
1589 future point. This function clears any such placeholder keys from the hash.
1590 See Hash::Util::lock_keys() for an example of its use.
1596 Perl_hv_clear_placeholders(pTHX_ HV *hv)
1599 const U32 items = (U32)HvPLACEHOLDERS_get(hv);
1601 PERL_ARGS_ASSERT_HV_CLEAR_PLACEHOLDERS;
1604 clear_placeholders(hv, items);
1608 S_clear_placeholders(pTHX_ HV *hv, U32 items)
1613 PERL_ARGS_ASSERT_CLEAR_PLACEHOLDERS;
1620 /* Loop down the linked list heads */
1622 HE **oentry = &(HvARRAY(hv))[i];
1625 while ((entry = *oentry)) {
1626 if (HeVAL(entry) == &PL_sv_placeholder) {
1627 *oentry = HeNEXT(entry);
1628 if (entry == HvEITER_get(hv))
1631 hv_free_ent(hv, entry);
1635 HvTOTALKEYS(hv) -= (IV)HvPLACEHOLDERS_get(hv);
1636 if (HvKEYS(hv) == 0)
1637 HvHASKFLAGS_off(hv);
1638 HvPLACEHOLDERS_set(hv, 0);
1642 oentry = &HeNEXT(entry);
1647 /* You can't get here, hence assertion should always fail. */
1648 assert (items == 0);
1653 S_hfreeentries(pTHX_ HV *hv)
1655 /* This is the array that we're going to restore */
1656 HE **const orig_array = HvARRAY(hv);
1661 PERL_ARGS_ASSERT_HFREEENTRIES;
1667 /* If the hash is actually a symbol table with a name, look after the
1669 struct xpvhv_aux *iter = HvAUX(hv);
1671 name = iter->xhv_name;
1672 name_count = iter->xhv_name_count;
1673 iter->xhv_name = NULL;
1679 /* orig_array remains unchanged throughout the loop. If after freeing all
1680 the entries it turns out that one of the little blighters has triggered
1681 an action that has caused HvARRAY to be re-allocated, then we set
1682 array to the new HvARRAY, and try again. */
1685 /* This is the one we're going to try to empty. First time round
1686 it's the original array. (Hopefully there will only be 1 time
1688 HE ** const array = HvARRAY(hv);
1691 /* Because we have taken xhv_name out, the only allocated pointer
1692 in the aux structure that might exist is the backreference array.
1697 struct mro_meta *meta;
1698 struct xpvhv_aux *iter = HvAUX(hv);
1699 /* weak references: if called from sv_clear(), the backrefs
1700 * should already have been killed; if there are any left, its
1701 * because we're doing hv_clear() or hv_undef(), and the HV
1702 * will continue to live.
1703 * Because while freeing the entries we fake up a NULL HvARRAY
1704 * (and hence HvAUX), we need to store the backref array
1705 * somewhere else; but it still needs to be visible in case
1706 * any the things we free happen to call sv_del_backref().
1707 * We do this by storing it in magic instead.
1708 * If, during the entry freeing, a destructor happens to add
1709 * a new weak backref, then sv_add_backref will look in both
1710 * places (magic in HvAUX) for the AV, but will create a new
1711 * AV in HvAUX if it can't find one (if it finds it in magic,
1712 * it moves it back into HvAUX. So at the end of the iteration
1713 * we have to allow for this. */
1716 if (iter->xhv_backreferences) {
1717 if (SvTYPE(iter->xhv_backreferences) == SVt_PVAV) {
1718 /* The sv_magic will increase the reference count of the AV,
1719 so we need to drop it first. */
1720 SvREFCNT_dec(iter->xhv_backreferences);
1721 if (AvFILLp(iter->xhv_backreferences) == -1) {
1722 /* Turns out that the array is empty. Just free it. */
1723 SvREFCNT_dec(iter->xhv_backreferences);
1726 sv_magic(MUTABLE_SV(hv),
1727 MUTABLE_SV(iter->xhv_backreferences),
1728 PERL_MAGIC_backref, NULL, 0);
1733 sv_magic(MUTABLE_SV(hv), NULL, PERL_MAGIC_backref, NULL, 0);
1734 mg = mg_find(MUTABLE_SV(hv), PERL_MAGIC_backref);
1735 mg->mg_obj = (SV*)iter->xhv_backreferences;
1737 iter->xhv_backreferences = NULL;
1740 entry = iter->xhv_eiter; /* HvEITER(hv) */
1741 if (entry && HvLAZYDEL(hv)) { /* was deleted earlier? */
1743 hv_free_ent(hv, entry);
1745 iter->xhv_riter = -1; /* HvRITER(hv) = -1 */
1746 iter->xhv_eiter = NULL; /* HvEITER(hv) = NULL */
1748 if((meta = iter->xhv_mro_meta)) {
1749 if (meta->mro_linear_all) {
1750 SvREFCNT_dec(MUTABLE_SV(meta->mro_linear_all));
1751 meta->mro_linear_all = NULL;
1752 /* This is just acting as a shortcut pointer. */
1753 meta->mro_linear_current = NULL;
1754 } else if (meta->mro_linear_current) {
1755 /* Only the current MRO is stored, so this owns the data.
1757 SvREFCNT_dec(meta->mro_linear_current);
1758 meta->mro_linear_current = NULL;
1760 if(meta->mro_nextmethod) SvREFCNT_dec(meta->mro_nextmethod);
1761 SvREFCNT_dec(meta->isa);
1763 iter->xhv_mro_meta = NULL;
1766 /* There are now no allocated pointers in the aux structure. */
1768 SvFLAGS(hv) &= ~SVf_OOK; /* Goodbye, aux structure. */
1769 /* What aux structure? */
1772 /* make everyone else think the array is empty, so that the destructors
1773 * called for freed entries can't recursively mess with us */
1775 ((XPVHV*) SvANY(hv))->xhv_keys = 0;
1779 /* Loop down the linked list heads */
1780 HE *entry = array[i];
1783 register HE * const oentry = entry;
1784 entry = HeNEXT(entry);
1785 hv_free_ent(hv, oentry);
1789 /* As there are no allocated pointers in the aux structure, it's now
1790 safe to free the array we just cleaned up, if it's not the one we're
1791 going to put back. */
1792 if (array != orig_array) {
1797 /* Good. No-one added anything this time round. */
1802 /* Someone attempted to iterate or set the hash name while we had
1803 the array set to 0. We'll catch backferences on the next time
1804 round the while loop. */
1805 assert(HvARRAY(hv));
1807 if (HvAUX(hv)->xhv_name) {
1808 if(HvAUX(hv)->xhv_name_count) {
1809 HEK ** const name = (HEK **)HvAUX(hv)->xhv_name;
1810 I32 const count = HvAUX(hv)->xhv_name_count;
1811 HEK **hekp = name + (count < 0 ? -count : count);
1812 while(hekp-- > name)
1813 unshare_hek_or_pvn(*hekp, 0, 0, 0);
1816 else unshare_hek_or_pvn(HvAUX(hv)->xhv_name, 0, 0, 0);
1820 if (--attempts == 0) {
1821 Perl_die(aTHX_ "panic: hfreeentries failed to free hash - something is repeatedly re-creating entries");
1825 HvARRAY(hv) = orig_array;
1827 /* If the hash was actually a symbol table, put the name back. */
1829 /* We have restored the original array. If name is non-NULL, then
1830 the original array had an aux structure at the end. So this is
1832 struct xpvhv_aux * const aux = HvAUX(hv);
1833 SvFLAGS(hv) |= SVf_OOK;
1834 aux->xhv_name = name;
1835 aux->xhv_name_count = name_count;
1840 =for apidoc hv_undef
1848 Perl_hv_undef(pTHX_ HV *hv)
1851 register XPVHV* xhv;
1856 DEBUG_A(Perl_hv_assert(aTHX_ hv));
1857 xhv = (XPVHV*)SvANY(hv);
1859 if ((name = HvENAME_get(hv)) && PL_phase != PERL_PHASE_DESTRUCT)
1861 /* Delete the @ISA element before calling mro_package_moved, so it
1863 (void)hv_delete(hv, "ISA", 3, G_DISCARD);
1864 mro_package_moved(NULL, hv, NULL, name, HvENAMELEN_get(hv));
1868 if (name || (name = HvNAME(hv))) {
1870 (void)hv_delete(PL_stashcache, name, HvNAMELEN_get(hv), G_DISCARD);
1871 hv_name_set(hv, NULL, 0, 0);
1873 SvFLAGS(hv) &= ~SVf_OOK;
1874 Safefree(HvARRAY(hv));
1875 xhv->xhv_max = 7; /* HvMAX(hv) = 7 (it's a normal hash) */
1877 HvPLACEHOLDERS_set(hv, 0);
1880 mg_clear(MUTABLE_SV(hv));
1886 Returns the number of hash buckets that happen to be in use. This function is
1887 wrapped by the macro C<HvFILL>.
1889 Previously this value was stored in the HV structure, rather than being
1890 calculated on demand.
1896 Perl_hv_fill(pTHX_ HV const *const hv)
1899 HE **ents = HvARRAY(hv);
1901 PERL_ARGS_ASSERT_HV_FILL;
1904 HE *const *const last = ents + HvMAX(hv);
1905 count = last + 1 - ents;
1910 } while (++ents <= last);
1915 static struct xpvhv_aux*
1916 S_hv_auxinit(HV *hv) {
1917 struct xpvhv_aux *iter;
1920 PERL_ARGS_ASSERT_HV_AUXINIT;
1923 Newxz(array, PERL_HV_ARRAY_ALLOC_BYTES(HvMAX(hv) + 1)
1924 + sizeof(struct xpvhv_aux), char);
1926 array = (char *) HvARRAY(hv);
1927 Renew(array, PERL_HV_ARRAY_ALLOC_BYTES(HvMAX(hv) + 1)
1928 + sizeof(struct xpvhv_aux), char);
1930 HvARRAY(hv) = (HE**) array;
1931 /* SvOOK_on(hv) attacks the IV flags. */
1932 SvFLAGS(hv) |= SVf_OOK;
1935 iter->xhv_riter = -1; /* HvRITER(hv) = -1 */
1936 iter->xhv_eiter = NULL; /* HvEITER(hv) = NULL */
1938 iter->xhv_name_count = 0;
1939 iter->xhv_backreferences = 0;
1940 iter->xhv_mro_meta = NULL;
1945 =for apidoc hv_iterinit
1947 Prepares a starting point to traverse a hash table. Returns the number of
1948 keys in the hash (i.e. the same as C<HvKEYS(hv)>). The return value is
1949 currently only meaningful for hashes without tie magic.
1951 NOTE: Before version 5.004_65, C<hv_iterinit> used to return the number of
1952 hash buckets that happen to be in use. If you still need that esoteric
1953 value, you can get it through the macro C<HvFILL(hv)>.
1960 Perl_hv_iterinit(pTHX_ HV *hv)
1962 PERL_ARGS_ASSERT_HV_ITERINIT;
1964 /* FIXME: Are we not NULL, or do we croak? Place bets now! */
1967 Perl_croak(aTHX_ "Bad hash");
1970 struct xpvhv_aux * const iter = HvAUX(hv);
1971 HE * const entry = iter->xhv_eiter; /* HvEITER(hv) */
1972 if (entry && HvLAZYDEL(hv)) { /* was deleted earlier? */
1974 hv_free_ent(hv, entry);
1976 iter->xhv_riter = -1; /* HvRITER(hv) = -1 */
1977 iter->xhv_eiter = NULL; /* HvEITER(hv) = NULL */
1982 /* used to be xhv->xhv_fill before 5.004_65 */
1983 return HvTOTALKEYS(hv);
1987 Perl_hv_riter_p(pTHX_ HV *hv) {
1988 struct xpvhv_aux *iter;
1990 PERL_ARGS_ASSERT_HV_RITER_P;
1993 Perl_croak(aTHX_ "Bad hash");
1995 iter = SvOOK(hv) ? HvAUX(hv) : hv_auxinit(hv);
1996 return &(iter->xhv_riter);
2000 Perl_hv_eiter_p(pTHX_ HV *hv) {
2001 struct xpvhv_aux *iter;
2003 PERL_ARGS_ASSERT_HV_EITER_P;
2006 Perl_croak(aTHX_ "Bad hash");
2008 iter = SvOOK(hv) ? HvAUX(hv) : hv_auxinit(hv);
2009 return &(iter->xhv_eiter);
2013 Perl_hv_riter_set(pTHX_ HV *hv, I32 riter) {
2014 struct xpvhv_aux *iter;
2016 PERL_ARGS_ASSERT_HV_RITER_SET;
2019 Perl_croak(aTHX_ "Bad hash");
2027 iter = hv_auxinit(hv);
2029 iter->xhv_riter = riter;
2033 Perl_hv_eiter_set(pTHX_ HV *hv, HE *eiter) {
2034 struct xpvhv_aux *iter;
2036 PERL_ARGS_ASSERT_HV_EITER_SET;
2039 Perl_croak(aTHX_ "Bad hash");
2044 /* 0 is the default so don't go malloc()ing a new structure just to
2049 iter = hv_auxinit(hv);
2051 iter->xhv_eiter = eiter;
2055 Perl_hv_name_set(pTHX_ HV *hv, const char *name, U32 len, U32 flags)
2058 struct xpvhv_aux *iter;
2062 PERL_ARGS_ASSERT_HV_NAME_SET;
2063 PERL_UNUSED_ARG(flags);
2066 Perl_croak(aTHX_ "panic: hv name too long (%"UVuf")", (UV) len);
2070 if (iter->xhv_name) {
2071 if(iter->xhv_name_count) {
2073 HEK ** const name = (HEK **)HvAUX(hv)->xhv_name;
2074 HEK **hekp = name + (
2075 iter->xhv_name_count < 0
2076 ? -iter->xhv_name_count
2077 : iter->xhv_name_count
2079 while(hekp-- > name+1)
2080 unshare_hek_or_pvn(*hekp, 0, 0, 0);
2081 /* The first elem may be null. */
2082 if(*name) unshare_hek_or_pvn(*name, 0, 0, 0);
2084 spot = &iter->xhv_name;
2085 iter->xhv_name_count = 0;
2088 spot = (HEK **)iter->xhv_name;
2089 if(iter->xhv_name_count > 0) {
2090 /* shift some things over */
2091 Renew(spot, iter->xhv_name_count, HEK *);
2092 spot[iter->xhv_name_count++] = spot[1];
2096 unshare_hek_or_pvn(*spot, 0, 0, 0);
2101 unshare_hek_or_pvn(iter->xhv_name, 0, 0, 0);
2102 spot = &iter->xhv_name;
2105 else spot = &iter->xhv_name;
2110 iter = hv_auxinit(hv);
2111 spot = &iter->xhv_name;
2113 PERL_HASH(hash, name, len);
2114 *spot = name ? share_hek(name, len, hash) : NULL;
2115 iter->xhv_name_count = 0;
2119 =for apidoc hv_ename_add
2121 Adds a name to a stash's internal list of effective names. See
2124 This is called when a stash is assigned to a new location in the symbol
2131 Perl_hv_ename_add(pTHX_ HV *hv, const char *name, U32 len)
2134 struct xpvhv_aux *aux = SvOOK(hv) ? HvAUX(hv) : hv_auxinit(hv);
2137 PERL_ARGS_ASSERT_HV_ENAME_ADD;
2140 Perl_croak(aTHX_ "panic: hv name too long (%"UVuf")", (UV) len);
2142 PERL_HASH(hash, name, len);
2144 if (aux->xhv_name_count) {
2145 HEK ** const xhv_name = (HEK **)aux->xhv_name;
2146 I32 count = aux->xhv_name_count;
2147 HEK **hekp = xhv_name + (count < 0 ? -count : count);
2148 while (hekp-- > xhv_name)
2150 HEK_LEN(*hekp) == (I32)len && memEQ(HEK_KEY(*hekp), name, len)
2152 if (hekp == xhv_name && count < 0)
2153 aux->xhv_name_count = -count;
2156 if (count < 0) aux->xhv_name_count--, count = -count;
2157 else aux->xhv_name_count++;
2158 Renewc(aux->xhv_name, count + 1, HEK *, HEK);
2159 ((HEK **)aux->xhv_name)[count] = share_hek(name, len, hash);
2162 HEK *existing_name = aux->xhv_name;
2164 existing_name && HEK_LEN(existing_name) == (I32)len
2165 && memEQ(HEK_KEY(existing_name), name, len)
2167 Newxc(aux->xhv_name, 2, HEK *, HEK);
2168 aux->xhv_name_count = existing_name ? 2 : -2;
2169 *(HEK **)aux->xhv_name = existing_name;
2170 ((HEK **)aux->xhv_name)[1] = share_hek(name, len, hash);
2175 =for apidoc hv_ename_delete
2177 Removes a name from a stash's internal list of effective names. If this is
2178 the name returned by C<HvENAME>, then another name in the list will take
2179 its place (C<HvENAME> will use it).
2181 This is called when a stash is deleted from the symbol table.
2187 Perl_hv_ename_delete(pTHX_ HV *hv, const char *name, U32 len)
2190 struct xpvhv_aux *aux;
2192 PERL_ARGS_ASSERT_HV_ENAME_DELETE;
2195 Perl_croak(aTHX_ "panic: hv name too long (%"UVuf")", (UV) len);
2197 if (!SvOOK(hv)) return;
2200 if (!aux->xhv_name) return;
2202 if (aux->xhv_name_count) {
2203 HEK ** const namep = (HEK **)aux->xhv_name;
2204 I32 const count = aux->xhv_name_count;
2205 HEK **victim = namep + (count < 0 ? -count : count);
2206 while (victim-- > namep + 1)
2208 HEK_LEN(*victim) == (I32)len
2209 && memEQ(HEK_KEY(*victim), name, len)
2211 unshare_hek_or_pvn(*victim, 0, 0, 0);
2212 if (count < 0) ++aux->xhv_name_count;
2213 else --aux->xhv_name_count;
2215 (aux->xhv_name_count == 1 || aux->xhv_name_count == -1)
2217 ) { /* if there are none left */
2219 aux->xhv_name = NULL;
2220 aux->xhv_name_count = 0;
2223 /* Move the last one back to fill the empty slot. It
2224 does not matter what order they are in. */
2225 *victim = *(namep + (count < 0 ? -count : count) - 1);
2230 count > 0 && HEK_LEN(*namep) == (I32)len
2231 && memEQ(HEK_KEY(*namep),name,len)
2233 aux->xhv_name_count = -count;
2237 HEK_LEN(aux->xhv_name) == (I32)len
2238 && memEQ(HEK_KEY(aux->xhv_name), name, len)
2240 const HEK * const namehek = aux->xhv_name;
2241 Newxc(aux->xhv_name, 1, HEK *, HEK);
2242 *(const HEK **)aux->xhv_name = namehek;
2243 aux->xhv_name_count = -1;
2248 Perl_hv_backreferences_p(pTHX_ HV *hv) {
2249 struct xpvhv_aux * const iter = SvOOK(hv) ? HvAUX(hv) : hv_auxinit(hv);
2251 PERL_ARGS_ASSERT_HV_BACKREFERENCES_P;
2252 PERL_UNUSED_CONTEXT;
2254 return &(iter->xhv_backreferences);
2258 Perl_hv_kill_backrefs(pTHX_ HV *hv) {
2261 PERL_ARGS_ASSERT_HV_KILL_BACKREFS;
2266 av = HvAUX(hv)->xhv_backreferences;
2269 HvAUX(hv)->xhv_backreferences = 0;
2270 Perl_sv_kill_backrefs(aTHX_ MUTABLE_SV(hv), av);
2271 if (SvTYPE(av) == SVt_PVAV)
2277 hv_iternext is implemented as a macro in hv.h
2279 =for apidoc hv_iternext
2281 Returns entries from a hash iterator. See C<hv_iterinit>.
2283 You may call C<hv_delete> or C<hv_delete_ent> on the hash entry that the
2284 iterator currently points to, without losing your place or invalidating your
2285 iterator. Note that in this case the current entry is deleted from the hash
2286 with your iterator holding the last reference to it. Your iterator is flagged
2287 to free the entry on the next call to C<hv_iternext>, so you must not discard
2288 your iterator immediately else the entry will leak - call C<hv_iternext> to
2289 trigger the resource deallocation.
2291 =for apidoc hv_iternext_flags
2293 Returns entries from a hash iterator. See C<hv_iterinit> and C<hv_iternext>.
2294 The C<flags> value will normally be zero; if HV_ITERNEXT_WANTPLACEHOLDERS is
2295 set the placeholders keys (for restricted hashes) will be returned in addition
2296 to normal keys. By default placeholders are automatically skipped over.
2297 Currently a placeholder is implemented with a value that is
2298 C<&Perl_sv_placeholder>. Note that the implementation of placeholders and
2299 restricted hashes may change, and the implementation currently is
2300 insufficiently abstracted for any change to be tidy.
2306 Perl_hv_iternext_flags(pTHX_ HV *hv, I32 flags)
2309 register XPVHV* xhv;
2313 struct xpvhv_aux *iter;
2315 PERL_ARGS_ASSERT_HV_ITERNEXT_FLAGS;
2318 Perl_croak(aTHX_ "Bad hash");
2320 xhv = (XPVHV*)SvANY(hv);
2323 /* Too many things (well, pp_each at least) merrily assume that you can
2324 call iv_iternext without calling hv_iterinit, so we'll have to deal
2330 oldentry = entry = iter->xhv_eiter; /* HvEITER(hv) */
2331 if (SvMAGICAL(hv) && SvRMAGICAL(hv)) {
2332 if ( ( mg = mg_find((const SV *)hv, PERL_MAGIC_tied) ) ) {
2333 SV * const key = sv_newmortal();
2335 sv_setsv(key, HeSVKEY_force(entry));
2336 SvREFCNT_dec(HeSVKEY(entry)); /* get rid of previous key */
2342 /* one HE per MAGICAL hash */
2343 iter->xhv_eiter = entry = new_HE(); /* HvEITER(hv) = new_HE() */
2345 Newxz(k, HEK_BASESIZE + sizeof(const SV *), char);
2347 HeKEY_hek(entry) = hek;
2348 HeKLEN(entry) = HEf_SVKEY;
2350 magic_nextpack(MUTABLE_SV(hv),mg,key);
2352 /* force key to stay around until next time */
2353 HeSVKEY_set(entry, SvREFCNT_inc_simple_NN(key));
2354 return entry; /* beware, hent_val is not set */
2356 SvREFCNT_dec(HeVAL(entry));
2357 Safefree(HeKEY_hek(entry));
2359 iter->xhv_eiter = NULL; /* HvEITER(hv) = NULL */
2363 #if defined(DYNAMIC_ENV_FETCH) && !defined(__riscos__) /* set up %ENV for iteration */
2364 if (!entry && SvRMAGICAL((const SV *)hv)
2365 && mg_find((const SV *)hv, PERL_MAGIC_env)) {
2368 /* The prime_env_iter() on VMS just loaded up new hash values
2369 * so the iteration count needs to be reset back to the beginning
2373 oldentry = entry = iter->xhv_eiter; /* HvEITER(hv) */
2378 /* hv_iterint now ensures this. */
2379 assert (HvARRAY(hv));
2381 /* At start of hash, entry is NULL. */
2384 entry = HeNEXT(entry);
2385 if (!(flags & HV_ITERNEXT_WANTPLACEHOLDERS)) {
2387 * Skip past any placeholders -- don't want to include them in
2390 while (entry && HeVAL(entry) == &PL_sv_placeholder) {
2391 entry = HeNEXT(entry);
2396 /* Skip the entire loop if the hash is empty. */
2397 if ((flags & HV_ITERNEXT_WANTPLACEHOLDERS)
2398 ? HvTOTALKEYS(hv) : HvUSEDKEYS(hv)) {
2400 /* OK. Come to the end of the current list. Grab the next one. */
2402 iter->xhv_riter++; /* HvRITER(hv)++ */
2403 if (iter->xhv_riter > (I32)xhv->xhv_max /* HvRITER(hv) > HvMAX(hv) */) {
2404 /* There is no next one. End of the hash. */
2405 iter->xhv_riter = -1; /* HvRITER(hv) = -1 */
2408 entry = (HvARRAY(hv))[iter->xhv_riter];
2410 if (!(flags & HV_ITERNEXT_WANTPLACEHOLDERS)) {
2411 /* If we have an entry, but it's a placeholder, don't count it.
2413 while (entry && HeVAL(entry) == &PL_sv_placeholder)
2414 entry = HeNEXT(entry);
2416 /* Will loop again if this linked list starts NULL
2417 (for HV_ITERNEXT_WANTPLACEHOLDERS)
2418 or if we run through it and find only placeholders. */
2422 if (oldentry && HvLAZYDEL(hv)) { /* was deleted earlier? */
2424 hv_free_ent(hv, oldentry);
2427 /*if (HvREHASH(hv) && entry && !HeKREHASH(entry))
2428 PerlIO_printf(PerlIO_stderr(), "Awooga %p %p\n", (void*)hv, (void*)entry);*/
2430 iter->xhv_eiter = entry; /* HvEITER(hv) = entry */
2435 =for apidoc hv_iterkey
2437 Returns the key from the current position of the hash iterator. See
2444 Perl_hv_iterkey(pTHX_ register HE *entry, I32 *retlen)
2446 PERL_ARGS_ASSERT_HV_ITERKEY;
2448 if (HeKLEN(entry) == HEf_SVKEY) {
2450 char * const p = SvPV(HeKEY_sv(entry), len);
2455 *retlen = HeKLEN(entry);
2456 return HeKEY(entry);
2460 /* unlike hv_iterval(), this always returns a mortal copy of the key */
2462 =for apidoc hv_iterkeysv
2464 Returns the key as an C<SV*> from the current position of the hash
2465 iterator. The return value will always be a mortal copy of the key. Also
2472 Perl_hv_iterkeysv(pTHX_ register HE *entry)
2474 PERL_ARGS_ASSERT_HV_ITERKEYSV;
2476 return sv_2mortal(newSVhek(HeKEY_hek(entry)));
2480 =for apidoc hv_iterval
2482 Returns the value from the current position of the hash iterator. See
2489 Perl_hv_iterval(pTHX_ HV *hv, register HE *entry)
2491 PERL_ARGS_ASSERT_HV_ITERVAL;
2493 if (SvRMAGICAL(hv)) {
2494 if (mg_find((const SV *)hv, PERL_MAGIC_tied)) {
2495 SV* const sv = sv_newmortal();
2496 if (HeKLEN(entry) == HEf_SVKEY)
2497 mg_copy(MUTABLE_SV(hv), sv, (char*)HeKEY_sv(entry), HEf_SVKEY);
2499 mg_copy(MUTABLE_SV(hv), sv, HeKEY(entry), HeKLEN(entry));
2503 return HeVAL(entry);
2507 =for apidoc hv_iternextsv
2509 Performs an C<hv_iternext>, C<hv_iterkey>, and C<hv_iterval> in one
2516 Perl_hv_iternextsv(pTHX_ HV *hv, char **key, I32 *retlen)
2518 HE * const he = hv_iternext_flags(hv, 0);
2520 PERL_ARGS_ASSERT_HV_ITERNEXTSV;
2524 *key = hv_iterkey(he, retlen);
2525 return hv_iterval(hv, he);
2532 =for apidoc hv_magic
2534 Adds magic to a hash. See C<sv_magic>.
2539 /* possibly free a shared string if no one has access to it
2540 * len and hash must both be valid for str.
2543 Perl_unsharepvn(pTHX_ const char *str, I32 len, U32 hash)
2545 unshare_hek_or_pvn (NULL, str, len, hash);
2550 Perl_unshare_hek(pTHX_ HEK *hek)
2553 unshare_hek_or_pvn(hek, NULL, 0, 0);
2556 /* possibly free a shared string if no one has access to it
2557 hek if non-NULL takes priority over the other 3, else str, len and hash
2558 are used. If so, len and hash must both be valid for str.
2561 S_unshare_hek_or_pvn(pTHX_ const HEK *hek, const char *str, I32 len, U32 hash)
2564 register XPVHV* xhv;
2566 register HE **oentry;
2568 bool is_utf8 = FALSE;
2570 const char * const save = str;
2571 struct shared_he *he = NULL;
2574 /* Find the shared he which is just before us in memory. */
2575 he = (struct shared_he *)(((char *)hek)
2576 - STRUCT_OFFSET(struct shared_he,
2579 /* Assert that the caller passed us a genuine (or at least consistent)
2581 assert (he->shared_he_he.hent_hek == hek);
2583 if (he->shared_he_he.he_valu.hent_refcount - 1) {
2584 --he->shared_he_he.he_valu.hent_refcount;
2588 hash = HEK_HASH(hek);
2589 } else if (len < 0) {
2590 STRLEN tmplen = -len;
2592 /* See the note in hv_fetch(). --jhi */
2593 str = (char*)bytes_from_utf8((U8*)str, &tmplen, &is_utf8);
2596 k_flags = HVhek_UTF8;
2598 k_flags |= HVhek_WASUTF8 | HVhek_FREEKEY;
2601 /* what follows was the moral equivalent of:
2602 if ((Svp = hv_fetch(PL_strtab, tmpsv, FALSE, hash))) {
2604 hv_delete(PL_strtab, str, len, G_DISCARD, hash);
2606 xhv = (XPVHV*)SvANY(PL_strtab);
2607 /* assert(xhv_array != 0) */
2608 first = oentry = &(HvARRAY(PL_strtab))[hash & (I32) HvMAX(PL_strtab)];
2610 const HE *const he_he = &(he->shared_he_he);
2611 for (entry = *oentry; entry; oentry = &HeNEXT(entry), entry = *oentry) {
2616 const int flags_masked = k_flags & HVhek_MASK;
2617 for (entry = *oentry; entry; oentry = &HeNEXT(entry), entry = *oentry) {
2618 if (HeHASH(entry) != hash) /* strings can't be equal */
2620 if (HeKLEN(entry) != len)
2622 if (HeKEY(entry) != str && memNE(HeKEY(entry),str,len)) /* is this it? */
2624 if (HeKFLAGS(entry) != flags_masked)
2631 if (--entry->he_valu.hent_refcount == 0) {
2632 *oentry = HeNEXT(entry);
2634 xhv->xhv_keys--; /* HvTOTALKEYS(hv)-- */
2639 Perl_ck_warner_d(aTHX_ packWARN(WARN_INTERNAL),
2640 "Attempt to free non-existent shared string '%s'%s"
2642 hek ? HEK_KEY(hek) : str,
2643 ((k_flags & HVhek_UTF8) ? " (utf8)" : "") pTHX__VALUE);
2644 if (k_flags & HVhek_FREEKEY)
2648 /* get a (constant) string ptr from the global string table
2649 * string will get added if it is not already there.
2650 * len and hash must both be valid for str.
2653 Perl_share_hek(pTHX_ const char *str, I32 len, register U32 hash)
2655 bool is_utf8 = FALSE;
2657 const char * const save = str;
2659 PERL_ARGS_ASSERT_SHARE_HEK;
2662 STRLEN tmplen = -len;
2664 /* See the note in hv_fetch(). --jhi */
2665 str = (char*)bytes_from_utf8((U8*)str, &tmplen, &is_utf8);
2667 /* If we were able to downgrade here, then than means that we were passed
2668 in a key which only had chars 0-255, but was utf8 encoded. */
2671 /* If we found we were able to downgrade the string to bytes, then
2672 we should flag that it needs upgrading on keys or each. Also flag
2673 that we need share_hek_flags to free the string. */
2675 flags |= HVhek_WASUTF8 | HVhek_FREEKEY;
2678 return share_hek_flags (str, len, hash, flags);
2682 S_share_hek_flags(pTHX_ const char *str, I32 len, register U32 hash, int flags)
2686 const int flags_masked = flags & HVhek_MASK;
2687 const U32 hindex = hash & (I32) HvMAX(PL_strtab);
2688 register XPVHV * const xhv = (XPVHV*)SvANY(PL_strtab);
2690 PERL_ARGS_ASSERT_SHARE_HEK_FLAGS;
2692 /* what follows is the moral equivalent of:
2694 if (!(Svp = hv_fetch(PL_strtab, str, len, FALSE)))
2695 hv_store(PL_strtab, str, len, NULL, hash);
2697 Can't rehash the shared string table, so not sure if it's worth
2698 counting the number of entries in the linked list
2701 /* assert(xhv_array != 0) */
2702 entry = (HvARRAY(PL_strtab))[hindex];
2703 for (;entry; entry = HeNEXT(entry)) {
2704 if (HeHASH(entry) != hash) /* strings can't be equal */
2706 if (HeKLEN(entry) != len)
2708 if (HeKEY(entry) != str && memNE(HeKEY(entry),str,len)) /* is this it? */
2710 if (HeKFLAGS(entry) != flags_masked)
2716 /* What used to be head of the list.
2717 If this is NULL, then we're the first entry for this slot, which
2718 means we need to increate fill. */
2719 struct shared_he *new_entry;
2722 HE **const head = &HvARRAY(PL_strtab)[hindex];
2723 HE *const next = *head;
2725 /* We don't actually store a HE from the arena and a regular HEK.
2726 Instead we allocate one chunk of memory big enough for both,
2727 and put the HEK straight after the HE. This way we can find the
2728 HEK directly from the HE.
2731 Newx(k, STRUCT_OFFSET(struct shared_he,
2732 shared_he_hek.hek_key[0]) + len + 2, char);
2733 new_entry = (struct shared_he *)k;
2734 entry = &(new_entry->shared_he_he);
2735 hek = &(new_entry->shared_he_hek);
2737 Copy(str, HEK_KEY(hek), len, char);
2738 HEK_KEY(hek)[len] = 0;
2740 HEK_HASH(hek) = hash;
2741 HEK_FLAGS(hek) = (unsigned char)flags_masked;
2743 /* Still "point" to the HEK, so that other code need not know what
2745 HeKEY_hek(entry) = hek;
2746 entry->he_valu.hent_refcount = 0;
2747 HeNEXT(entry) = next;
2750 xhv->xhv_keys++; /* HvTOTALKEYS(hv)++ */
2751 if (!next) { /* initial entry? */
2752 } else if (xhv->xhv_keys > xhv->xhv_max /* HvKEYS(hv) > HvMAX(hv) */) {
2757 ++entry->he_valu.hent_refcount;
2759 if (flags & HVhek_FREEKEY)
2762 return HeKEY_hek(entry);
2766 Perl_hv_placeholders_p(pTHX_ HV *hv)
2769 MAGIC *mg = mg_find((const SV *)hv, PERL_MAGIC_rhash);
2771 PERL_ARGS_ASSERT_HV_PLACEHOLDERS_P;
2774 mg = sv_magicext(MUTABLE_SV(hv), 0, PERL_MAGIC_rhash, 0, 0, 0);
2777 Perl_die(aTHX_ "panic: hv_placeholders_p");
2780 return &(mg->mg_len);
2785 Perl_hv_placeholders_get(pTHX_ const HV *hv)
2788 MAGIC * const mg = mg_find((const SV *)hv, PERL_MAGIC_rhash);
2790 PERL_ARGS_ASSERT_HV_PLACEHOLDERS_GET;
2792 return mg ? mg->mg_len : 0;
2796 Perl_hv_placeholders_set(pTHX_ HV *hv, I32 ph)
2799 MAGIC * const mg = mg_find((const SV *)hv, PERL_MAGIC_rhash);
2801 PERL_ARGS_ASSERT_HV_PLACEHOLDERS_SET;
2806 if (!sv_magicext(MUTABLE_SV(hv), 0, PERL_MAGIC_rhash, 0, 0, ph))
2807 Perl_die(aTHX_ "panic: hv_placeholders_set");
2809 /* else we don't need to add magic to record 0 placeholders. */
2813 S_refcounted_he_value(pTHX_ const struct refcounted_he *he)
2818 PERL_ARGS_ASSERT_REFCOUNTED_HE_VALUE;
2820 switch(he->refcounted_he_data[0] & HVrhek_typemask) {
2825 value = &PL_sv_placeholder;
2828 value = newSViv(he->refcounted_he_val.refcounted_he_u_iv);
2831 value = newSVuv(he->refcounted_he_val.refcounted_he_u_uv);
2834 case HVrhek_PV_UTF8:
2835 /* Create a string SV that directly points to the bytes in our
2837 value = newSV_type(SVt_PV);
2838 SvPV_set(value, (char *) he->refcounted_he_data + 1);
2839 SvCUR_set(value, he->refcounted_he_val.refcounted_he_u_len);
2840 /* This stops anything trying to free it */
2841 SvLEN_set(value, 0);
2843 SvREADONLY_on(value);
2844 if ((he->refcounted_he_data[0] & HVrhek_typemask) == HVrhek_PV_UTF8)
2848 Perl_croak(aTHX_ "panic: refcounted_he_value bad flags %"UVxf,
2849 (UV)he->refcounted_he_data[0]);
2855 =for apidoc m|HV *|refcounted_he_chain_2hv|const struct refcounted_he *c|U32 flags
2857 Generates and returns a C<HV *> representing the content of a
2858 C<refcounted_he> chain.
2859 I<flags> is currently unused and must be zero.
2864 Perl_refcounted_he_chain_2hv(pTHX_ const struct refcounted_he *chain, U32 flags)
2868 U32 placeholders, max;
2871 Perl_croak(aTHX_ "panic: refcounted_he_chain_2hv bad flags %"UVxf,
2874 /* We could chase the chain once to get an idea of the number of keys,
2875 and call ksplit. But for now we'll make a potentially inefficient
2876 hash with only 8 entries in its array. */
2881 Newxz(array, PERL_HV_ARRAY_ALLOC_BYTES(max + 1), char);
2882 HvARRAY(hv) = (HE**)array;
2888 U32 hash = chain->refcounted_he_hash;
2890 U32 hash = HEK_HASH(chain->refcounted_he_hek);
2892 HE **oentry = &((HvARRAY(hv))[hash & max]);
2893 HE *entry = *oentry;
2896 for (; entry; entry = HeNEXT(entry)) {
2897 if (HeHASH(entry) == hash) {
2898 /* We might have a duplicate key here. If so, entry is older
2899 than the key we've already put in the hash, so if they are
2900 the same, skip adding entry. */
2902 const STRLEN klen = HeKLEN(entry);
2903 const char *const key = HeKEY(entry);
2904 if (klen == chain->refcounted_he_keylen
2905 && (!!HeKUTF8(entry)
2906 == !!(chain->refcounted_he_data[0] & HVhek_UTF8))
2907 && memEQ(key, REF_HE_KEY(chain), klen))
2910 if (HeKEY_hek(entry) == chain->refcounted_he_hek)
2912 if (HeKLEN(entry) == HEK_LEN(chain->refcounted_he_hek)
2913 && HeKUTF8(entry) == HEK_UTF8(chain->refcounted_he_hek)
2914 && memEQ(HeKEY(entry), HEK_KEY(chain->refcounted_he_hek),
2925 = share_hek_flags(REF_HE_KEY(chain),
2926 chain->refcounted_he_keylen,
2927 chain->refcounted_he_hash,
2928 (chain->refcounted_he_data[0]
2929 & (HVhek_UTF8|HVhek_WASUTF8)));
2931 HeKEY_hek(entry) = share_hek_hek(chain->refcounted_he_hek);
2933 value = refcounted_he_value(chain);
2934 if (value == &PL_sv_placeholder)
2936 HeVAL(entry) = value;
2938 /* Link it into the chain. */
2939 HeNEXT(entry) = *oentry;
2945 chain = chain->refcounted_he_next;
2949 clear_placeholders(hv, placeholders);
2950 HvTOTALKEYS(hv) -= placeholders;
2953 /* We could check in the loop to see if we encounter any keys with key
2954 flags, but it's probably not worth it, as this per-hash flag is only
2955 really meant as an optimisation for things like Storable. */
2957 DEBUG_A(Perl_hv_assert(aTHX_ hv));
2963 =for apidoc m|SV *|refcounted_he_fetch_pvn|const struct refcounted_he *chain|const char *keypv|STRLEN keylen|U32 hash|U32 flags
2965 Search along a C<refcounted_he> chain for an entry with the key specified
2966 by I<keypv> and I<keylen>. If I<flags> has the C<REFCOUNTED_HE_KEY_UTF8>
2967 bit set, the key octets are interpreted as UTF-8, otherwise they
2968 are interpreted as Latin-1. I<hash> is a precomputed hash of the key
2969 string, or zero if it has not been precomputed. Returns a mortal scalar
2970 representing the value associated with the key, or C<&PL_sv_placeholder>
2971 if there is no value associated with the key.
2977 Perl_refcounted_he_fetch_pvn(pTHX_ const struct refcounted_he *chain,
2978 const char *keypv, STRLEN keylen, U32 hash, U32 flags)
2982 PERL_ARGS_ASSERT_REFCOUNTED_HE_FETCH_PVN;
2984 if (flags & ~REFCOUNTED_HE_KEY_UTF8)
2985 Perl_croak(aTHX_ "panic: refcounted_he_fetch_pvn bad flags %"UVxf,
2988 return &PL_sv_placeholder;
2989 if (flags & REFCOUNTED_HE_KEY_UTF8) {
2990 /* For searching purposes, canonicalise to Latin-1 where possible. */
2991 const char *keyend = keypv + keylen, *p;
2992 STRLEN nonascii_count = 0;
2993 for (p = keypv; p != keyend; p++) {
2996 if (!((c & 0xfe) == 0xc2 && ++p != keyend &&
2997 (((U8)*p) & 0xc0) == 0x80))
2998 goto canonicalised_key;
3002 if (nonascii_count) {
3004 const char *p = keypv, *keyend = keypv + keylen;
3005 keylen -= nonascii_count;
3006 Newx(q, keylen, char);
3009 for (; p != keyend; p++, q++) {
3012 ((c & 0x80) ? ((c & 0x03) << 6) | (((U8)*++p) & 0x3f) : c);
3015 flags &= ~REFCOUNTED_HE_KEY_UTF8;
3016 canonicalised_key: ;
3018 utf8_flag = (flags & REFCOUNTED_HE_KEY_UTF8) ? HVhek_UTF8 : 0;
3020 PERL_HASH(hash, keypv, keylen);
3022 for (; chain; chain = chain->refcounted_he_next) {
3025 hash == chain->refcounted_he_hash &&
3026 keylen == chain->refcounted_he_keylen &&
3027 memEQ(REF_HE_KEY(chain), keypv, keylen) &&
3028 utf8_flag == (chain->refcounted_he_data[0] & HVhek_UTF8)
3030 hash == HEK_HASH(chain->refcounted_he_hek) &&
3031 keylen == (STRLEN)HEK_LEN(chain->refcounted_he_hek) &&
3032 memEQ(HEK_KEY(chain->refcounted_he_hek), keypv, keylen) &&
3033 utf8_flag == (HEK_FLAGS(chain->refcounted_he_hek) & HVhek_UTF8)
3036 return sv_2mortal(refcounted_he_value(chain));
3038 return &PL_sv_placeholder;
3042 =for apidoc m|SV *|refcounted_he_fetch_pv|const struct refcounted_he *chain|const char *key|U32 hash|U32 flags
3044 Like L</refcounted_he_fetch_pvn>, but takes a nul-terminated string
3045 instead of a string/length pair.
3051 Perl_refcounted_he_fetch_pv(pTHX_ const struct refcounted_he *chain,
3052 const char *key, U32 hash, U32 flags)
3054 PERL_ARGS_ASSERT_REFCOUNTED_HE_FETCH_PV;
3055 return refcounted_he_fetch_pvn(chain, key, strlen(key), hash, flags);
3059 =for apidoc m|SV *|refcounted_he_fetch_sv|const struct refcounted_he *chain|SV *key|U32 hash|U32 flags
3061 Like L</refcounted_he_fetch_pvn>, but takes a Perl scalar instead of a
3068 Perl_refcounted_he_fetch_sv(pTHX_ const struct refcounted_he *chain,
3069 SV *key, U32 hash, U32 flags)
3073 PERL_ARGS_ASSERT_REFCOUNTED_HE_FETCH_SV;
3074 if (flags & REFCOUNTED_HE_KEY_UTF8)
3075 Perl_croak(aTHX_ "panic: refcounted_he_fetch_sv bad flags %"UVxf,
3077 keypv = SvPV_const(key, keylen);
3079 flags |= REFCOUNTED_HE_KEY_UTF8;
3080 if (!hash && SvIsCOW_shared_hash(key))
3081 hash = SvSHARED_HASH(key);
3082 return refcounted_he_fetch_pvn(chain, keypv, keylen, hash, flags);
3086 =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
3088 Creates a new C<refcounted_he>. This consists of a single key/value
3089 pair and a reference to an existing C<refcounted_he> chain (which may
3090 be empty), and thus forms a longer chain. When using the longer chain,
3091 the new key/value pair takes precedence over any entry for the same key
3092 further along the chain.
3094 The new key is specified by I<keypv> and I<keylen>. If I<flags> has
3095 the C<REFCOUNTED_HE_KEY_UTF8> bit set, the key octets are interpreted
3096 as UTF-8, otherwise they are interpreted as Latin-1. I<hash> is
3097 a precomputed hash of the key string, or zero if it has not been
3100 I<value> is the scalar value to store for this key. I<value> is copied
3101 by this function, which thus does not take ownership of any reference
3102 to it, and later changes to the scalar will not be reflected in the
3103 value visible in the C<refcounted_he>. Complex types of scalar will not
3104 be stored with referential integrity, but will be coerced to strings.
3105 I<value> may be either null or C<&PL_sv_placeholder> to indicate that no
3106 value is to be associated with the key; this, as with any non-null value,
3107 takes precedence over the existence of a value for the key further along
3110 I<parent> points to the rest of the C<refcounted_he> chain to be
3111 attached to the new C<refcounted_he>. This function takes ownership
3112 of one reference to I<parent>, and returns one reference to the new
3118 struct refcounted_he *
3119 Perl_refcounted_he_new_pvn(pTHX_ struct refcounted_he *parent,
3120 const char *keypv, STRLEN keylen, U32 hash, SV *value, U32 flags)
3123 STRLEN value_len = 0;
3124 const char *value_p = NULL;
3128 STRLEN key_offset = 1;
3129 struct refcounted_he *he;
3130 PERL_ARGS_ASSERT_REFCOUNTED_HE_NEW_PVN;
3132 if (!value || value == &PL_sv_placeholder) {
3133 value_type = HVrhek_delete;
3134 } else if (SvPOK(value)) {
3135 value_type = HVrhek_PV;
3136 } else if (SvIOK(value)) {
3137 value_type = SvUOK((const SV *)value) ? HVrhek_UV : HVrhek_IV;
3138 } else if (!SvOK(value)) {
3139 value_type = HVrhek_undef;
3141 value_type = HVrhek_PV;
3143 is_pv = value_type == HVrhek_PV;
3145 /* Do it this way so that the SvUTF8() test is after the SvPV, in case
3146 the value is overloaded, and doesn't yet have the UTF-8flag set. */
3147 value_p = SvPV_const(value, value_len);
3149 value_type = HVrhek_PV_UTF8;
3150 key_offset = value_len + 2;
3152 hekflags = value_type;
3154 if (flags & REFCOUNTED_HE_KEY_UTF8) {
3155 /* Canonicalise to Latin-1 where possible. */
3156 const char *keyend = keypv + keylen, *p;
3157 STRLEN nonascii_count = 0;
3158 for (p = keypv; p != keyend; p++) {
3161 if (!((c & 0xfe) == 0xc2 && ++p != keyend &&
3162 (((U8)*p) & 0xc0) == 0x80))
3163 goto canonicalised_key;
3167 if (nonascii_count) {
3169 const char *p = keypv, *keyend = keypv + keylen;
3170 keylen -= nonascii_count;
3171 Newx(q, keylen, char);
3174 for (; p != keyend; p++, q++) {
3177 ((c & 0x80) ? ((c & 0x03) << 6) | (((U8)*++p) & 0x3f) : c);
3180 flags &= ~REFCOUNTED_HE_KEY_UTF8;
3181 canonicalised_key: ;
3183 if (flags & REFCOUNTED_HE_KEY_UTF8)
3184 hekflags |= HVhek_UTF8;
3186 PERL_HASH(hash, keypv, keylen);
3189 he = (struct refcounted_he*)
3190 PerlMemShared_malloc(sizeof(struct refcounted_he) - 1
3194 he = (struct refcounted_he*)
3195 PerlMemShared_malloc(sizeof(struct refcounted_he) - 1
3199 he->refcounted_he_next = parent;
3202 Copy(value_p, he->refcounted_he_data + 1, value_len + 1, char);
3203 he->refcounted_he_val.refcounted_he_u_len = value_len;
3204 } else if (value_type == HVrhek_IV) {
3205 he->refcounted_he_val.refcounted_he_u_iv = SvIVX(value);
3206 } else if (value_type == HVrhek_UV) {
3207 he->refcounted_he_val.refcounted_he_u_uv = SvUVX(value);
3211 he->refcounted_he_hash = hash;
3212 he->refcounted_he_keylen = keylen;
3213 Copy(keypv, he->refcounted_he_data + key_offset, keylen, char);
3215 he->refcounted_he_hek = share_hek_flags(keypv, keylen, hash, hekflags);
3218 he->refcounted_he_data[0] = hekflags;
3219 he->refcounted_he_refcnt = 1;
3225 =for apidoc m|struct refcounted_he *|refcounted_he_new_pv|struct refcounted_he *parent|const char *key|U32 hash|SV *value|U32 flags
3227 Like L</refcounted_he_new_pvn>, but takes a nul-terminated string instead
3228 of a string/length pair.
3233 struct refcounted_he *
3234 Perl_refcounted_he_new_pv(pTHX_ struct refcounted_he *parent,
3235 const char *key, U32 hash, SV *value, U32 flags)
3237 PERL_ARGS_ASSERT_REFCOUNTED_HE_NEW_PV;
3238 return refcounted_he_new_pvn(parent, key, strlen(key), hash, value, flags);
3242 =for apidoc m|struct refcounted_he *|refcounted_he_new_sv|struct refcounted_he *parent|SV *key|U32 hash|SV *value|U32 flags
3244 Like L</refcounted_he_new_pvn>, but takes a Perl scalar instead of a
3250 struct refcounted_he *
3251 Perl_refcounted_he_new_sv(pTHX_ struct refcounted_he *parent,
3252 SV *key, U32 hash, SV *value, U32 flags)
3256 PERL_ARGS_ASSERT_REFCOUNTED_HE_NEW_SV;
3257 if (flags & REFCOUNTED_HE_KEY_UTF8)
3258 Perl_croak(aTHX_ "panic: refcounted_he_new_sv bad flags %"UVxf,
3260 keypv = SvPV_const(key, keylen);
3262 flags |= REFCOUNTED_HE_KEY_UTF8;
3263 if (!hash && SvIsCOW_shared_hash(key))
3264 hash = SvSHARED_HASH(key);
3265 return refcounted_he_new_pvn(parent, keypv, keylen, hash, value, flags);
3269 =for apidoc m|void|refcounted_he_free|struct refcounted_he *he
3271 Decrements the reference count of a C<refcounted_he> by one. If the
3272 reference count reaches zero the structure's memory is freed, which
3273 (recursively) causes a reduction of its parent C<refcounted_he>'s
3274 reference count. It is safe to pass a null pointer to this function:
3275 no action occurs in this case.
3281 Perl_refcounted_he_free(pTHX_ struct refcounted_he *he) {
3283 PERL_UNUSED_CONTEXT;
3286 struct refcounted_he *copy;
3290 new_count = --he->refcounted_he_refcnt;
3291 HINTS_REFCNT_UNLOCK;
3297 #ifndef USE_ITHREADS
3298 unshare_hek_or_pvn (he->refcounted_he_hek, 0, 0, 0);
3301 he = he->refcounted_he_next;
3302 PerlMemShared_free(copy);
3307 =for apidoc m|struct refcounted_he *|refcounted_he_inc|struct refcounted_he *he
3309 Increment the reference count of a C<refcounted_he>. The pointer to the
3310 C<refcounted_he> is also returned. It is safe to pass a null pointer
3311 to this function: no action occurs and a null pointer is returned.
3316 struct refcounted_he *
3317 Perl_refcounted_he_inc(pTHX_ struct refcounted_he *he)
3321 he->refcounted_he_refcnt++;
3322 HINTS_REFCNT_UNLOCK;
3327 /* pp_entereval is aware that labels are stored with a key ':' at the top of
3330 Perl_fetch_cop_label(pTHX_ COP *const cop, STRLEN *len, U32 *flags) {
3331 struct refcounted_he *const chain = cop->cop_hints_hash;
3333 PERL_ARGS_ASSERT_FETCH_COP_LABEL;
3338 if (chain->refcounted_he_keylen != 1)
3340 if (*REF_HE_KEY(chain) != ':')
3343 if ((STRLEN)HEK_LEN(chain->refcounted_he_hek) != 1)
3345 if (*HEK_KEY(chain->refcounted_he_hek) != ':')
3348 /* Stop anyone trying to really mess us up by adding their own value for
3350 if ((chain->refcounted_he_data[0] & HVrhek_typemask) != HVrhek_PV
3351 && (chain->refcounted_he_data[0] & HVrhek_typemask) != HVrhek_PV_UTF8)
3355 *len = chain->refcounted_he_val.refcounted_he_u_len;
3357 *flags = ((chain->refcounted_he_data[0] & HVrhek_typemask)
3358 == HVrhek_PV_UTF8) ? SVf_UTF8 : 0;
3360 return chain->refcounted_he_data + 1;
3364 Perl_store_cop_label(pTHX_ COP *const cop, const char *label, STRLEN len,
3368 PERL_ARGS_ASSERT_STORE_COP_LABEL;
3370 if (flags & ~(SVf_UTF8))
3371 Perl_croak(aTHX_ "panic: store_cop_label illegal flag bits 0x%" UVxf,
3373 labelsv = sv_2mortal(newSVpvn(label, len));
3374 if (flags & SVf_UTF8)
3377 = refcounted_he_new_pvs(cop->cop_hints_hash, ":", labelsv, 0);
3381 =for apidoc hv_assert
3383 Check that a hash is in an internally consistent state.
3391 Perl_hv_assert(pTHX_ HV *hv)
3396 int placeholders = 0;
3399 const I32 riter = HvRITER_get(hv);
3400 HE *eiter = HvEITER_get(hv);
3402 PERL_ARGS_ASSERT_HV_ASSERT;
3404 (void)hv_iterinit(hv);
3406 while ((entry = hv_iternext_flags(hv, HV_ITERNEXT_WANTPLACEHOLDERS))) {
3407 /* sanity check the values */
3408 if (HeVAL(entry) == &PL_sv_placeholder)
3412 /* sanity check the keys */
3413 if (HeSVKEY(entry)) {
3414 NOOP; /* Don't know what to check on SV keys. */
3415 } else if (HeKUTF8(entry)) {
3417 if (HeKWASUTF8(entry)) {
3418 PerlIO_printf(Perl_debug_log,
3419 "hash key has both WASUTF8 and UTF8: '%.*s'\n",
3420 (int) HeKLEN(entry), HeKEY(entry));
3423 } else if (HeKWASUTF8(entry))
3426 if (!SvTIED_mg((const SV *)hv, PERL_MAGIC_tied)) {
3427 static const char bad_count[] = "Count %d %s(s), but hash reports %d\n";
3428 const int nhashkeys = HvUSEDKEYS(hv);
3429 const int nhashplaceholders = HvPLACEHOLDERS_get(hv);
3431 if (nhashkeys != real) {
3432 PerlIO_printf(Perl_debug_log, bad_count, real, "keys", nhashkeys );
3435 if (nhashplaceholders != placeholders) {
3436 PerlIO_printf(Perl_debug_log, bad_count, placeholders, "placeholder", nhashplaceholders );
3440 if (withflags && ! HvHASKFLAGS(hv)) {
3441 PerlIO_printf(Perl_debug_log,
3442 "Hash has HASKFLAGS off but I count %d key(s) with flags\n",
3447 sv_dump(MUTABLE_SV(hv));
3449 HvRITER_set(hv, riter); /* Restore hash iterator state */
3450 HvEITER_set(hv, eiter);
3457 * c-indentation-style: bsd
3459 * indent-tabs-mode: t
3462 * ex: set ts=8 sts=4 sw=4 noet: