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 actually 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) {
803 /* Use only the old HvKEYS(hv) > HvMAX(hv) condition to limit
804 bucket splits on a rehashed hash, as we're not going to
805 split it again, and if someone is lucky (evil) enough to
806 get all the keys in one list they could exhaust our memory
807 as we repeatedly double the number of buckets on every
808 entry. Linear search feels a less worse thing to do. */
810 } else if(!HvREHASH(hv)) {
813 while ((counter = HeNEXT(counter)))
816 if (n_links > HV_MAX_LENGTH_BEFORE_SPLIT) {
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);
1030 (klen > 1 && key[klen-2] == ':' && key[klen-1] == ':')
1032 (klen == 1 && key[0] == ':')
1034 && (klen != 6 || hv!=PL_defstash || memNE(key,"main::",6))
1035 && SvTYPE(gv) == SVt_PVGV && (stash = GvHV((GV *)gv))
1036 && HvENAME_get(stash)) {
1037 /* A previous version of this code checked that the
1038 * GV was still in the symbol table by fetching the
1039 * GV with its name. That is not necessary (and
1040 * sometimes incorrect), as HvENAME cannot be set
1041 * on hv if it is not in the symtab. */
1043 /* Hang on to it for a bit. */
1044 SvREFCNT_inc_simple_void_NN(
1045 sv_2mortal((SV *)gv)
1048 else if (klen == 3 && strnEQ(key, "ISA", 3))
1052 if (d_flags & G_DISCARD)
1055 sv = sv_2mortal(HeVAL(entry));
1056 HeVAL(entry) = &PL_sv_placeholder;
1060 * If a restricted hash, rather than really deleting the entry, put
1061 * a placeholder there. This marks the key as being "approved", so
1062 * we can still access via not-really-existing key without raising
1065 if (SvREADONLY(hv)) {
1066 SvREFCNT_dec(HeVAL(entry));
1067 HeVAL(entry) = &PL_sv_placeholder;
1068 /* We'll be saving this slot, so the number of allocated keys
1069 * doesn't go down, but the number placeholders goes up */
1070 HvPLACEHOLDERS(hv)++;
1072 *oentry = HeNEXT(entry);
1073 if (SvOOK(hv) && entry == HvAUX(hv)->xhv_eiter /* HvEITER(hv) */)
1076 hv_free_ent(hv, entry);
1077 xhv->xhv_keys--; /* HvTOTALKEYS(hv)-- */
1078 if (xhv->xhv_keys == 0)
1079 HvHASKFLAGS_off(hv);
1082 if (mro_changes == 1) mro_isa_changed_in(hv);
1083 else if (mro_changes == 2)
1084 mro_package_moved(NULL, stash, gv, 1);
1088 if (SvREADONLY(hv)) {
1089 hv_notallowed(k_flags, key, klen,
1090 "Attempt to delete disallowed key '%"SVf"' from"
1091 " a restricted hash");
1094 if (k_flags & HVhek_FREEKEY)
1100 S_hsplit(pTHX_ HV *hv)
1103 register XPVHV* const xhv = (XPVHV*)SvANY(hv);
1104 const I32 oldsize = (I32) xhv->xhv_max+1; /* HvMAX(hv)+1 (sick) */
1105 register I32 newsize = oldsize * 2;
1107 char *a = (char*) HvARRAY(hv);
1109 int longest_chain = 0;
1112 PERL_ARGS_ASSERT_HSPLIT;
1114 /*PerlIO_printf(PerlIO_stderr(), "hsplit called for %p which had %d\n",
1115 (void*)hv, (int) oldsize);*/
1117 if (HvPLACEHOLDERS_get(hv) && !SvREADONLY(hv)) {
1118 /* Can make this clear any placeholders first for non-restricted hashes,
1119 even though Storable rebuilds restricted hashes by putting in all the
1120 placeholders (first) before turning on the readonly flag, because
1121 Storable always pre-splits the hash. */
1122 hv_clear_placeholders(hv);
1126 #if defined(STRANGE_MALLOC) || defined(MYMALLOC)
1127 Renew(a, PERL_HV_ARRAY_ALLOC_BYTES(newsize)
1128 + (SvOOK(hv) ? sizeof(struct xpvhv_aux) : 0), char);
1134 Move(&a[oldsize * sizeof(HE*)], &a[newsize * sizeof(HE*)], 1, struct xpvhv_aux);
1137 Newx(a, PERL_HV_ARRAY_ALLOC_BYTES(newsize)
1138 + (SvOOK(hv) ? sizeof(struct xpvhv_aux) : 0), char);
1143 Copy(HvARRAY(hv), a, oldsize * sizeof(HE*), char);
1145 Copy(HvAUX(hv), &a[newsize * sizeof(HE*)], 1, struct xpvhv_aux);
1147 Safefree(HvARRAY(hv));
1151 Zero(&a[oldsize * sizeof(HE*)], (newsize-oldsize) * sizeof(HE*), char); /* zero 2nd half*/
1152 xhv->xhv_max = --newsize; /* HvMAX(hv) = --newsize */
1153 HvARRAY(hv) = (HE**) a;
1156 for (i=0; i<oldsize; i++,aep++) {
1157 int left_length = 0;
1158 int right_length = 0;
1163 if (!entry) /* non-existent */
1167 if ((HeHASH(entry) & newsize) != (U32)i) {
1168 *oentry = HeNEXT(entry);
1169 HeNEXT(entry) = *bep;
1174 oentry = &HeNEXT(entry);
1179 /* I think we don't actually need to keep track of the longest length,
1180 merely flag if anything is too long. But for the moment while
1181 developing this code I'll track it. */
1182 if (left_length > longest_chain)
1183 longest_chain = left_length;
1184 if (right_length > longest_chain)
1185 longest_chain = right_length;
1189 /* Pick your policy for "hashing isn't working" here: */
1190 if (longest_chain <= HV_MAX_LENGTH_BEFORE_SPLIT /* split worked? */
1195 if (hv == PL_strtab) {
1196 /* Urg. Someone is doing something nasty to the string table.
1201 /* Awooga. Awooga. Pathological data. */
1202 /*PerlIO_printf(PerlIO_stderr(), "%p %d of %d with %d/%d buckets\n", (void*)hv,
1203 longest_chain, HvTOTALKEYS(hv), HvFILL(hv), 1+HvMAX(hv));*/
1206 Newxz(a, PERL_HV_ARRAY_ALLOC_BYTES(newsize)
1207 + (SvOOK(hv) ? sizeof(struct xpvhv_aux) : 0), char);
1209 Copy(HvAUX(hv), &a[newsize * sizeof(HE*)], 1, struct xpvhv_aux);
1212 was_shared = HvSHAREKEYS(hv);
1214 HvSHAREKEYS_off(hv);
1219 for (i=0; i<newsize; i++,aep++) {
1220 register HE *entry = *aep;
1222 /* We're going to trash this HE's next pointer when we chain it
1223 into the new hash below, so store where we go next. */
1224 HE * const next = HeNEXT(entry);
1229 PERL_HASH_INTERNAL(hash, HeKEY(entry), HeKLEN(entry));
1234 = save_hek_flags(HeKEY(entry), HeKLEN(entry),
1235 hash, HeKFLAGS(entry));
1236 unshare_hek (HeKEY_hek(entry));
1237 HeKEY_hek(entry) = new_hek;
1239 /* Not shared, so simply write the new hash in. */
1240 HeHASH(entry) = hash;
1242 /*PerlIO_printf(PerlIO_stderr(), "%d ", HeKFLAGS(entry));*/
1243 HEK_REHASH_on(HeKEY_hek(entry));
1244 /*PerlIO_printf(PerlIO_stderr(), "%d\n", HeKFLAGS(entry));*/
1246 /* Copy oentry to the correct new chain. */
1247 bep = ((HE**)a) + (hash & (I32) xhv->xhv_max);
1248 HeNEXT(entry) = *bep;
1254 Safefree (HvARRAY(hv));
1255 HvARRAY(hv) = (HE **)a;
1259 Perl_hv_ksplit(pTHX_ HV *hv, IV newmax)
1262 register XPVHV* xhv = (XPVHV*)SvANY(hv);
1263 const I32 oldsize = (I32) xhv->xhv_max+1; /* HvMAX(hv)+1 (sick) */
1264 register I32 newsize;
1269 PERL_ARGS_ASSERT_HV_KSPLIT;
1271 newsize = (I32) newmax; /* possible truncation here */
1272 if (newsize != newmax || newmax <= oldsize)
1274 while ((newsize & (1 + ~newsize)) != newsize) {
1275 newsize &= ~(newsize & (1 + ~newsize)); /* get proper power of 2 */
1277 if (newsize < newmax)
1279 if (newsize < newmax)
1280 return; /* overflow detection */
1282 a = (char *) HvARRAY(hv);
1285 #if defined(STRANGE_MALLOC) || defined(MYMALLOC)
1286 Renew(a, PERL_HV_ARRAY_ALLOC_BYTES(newsize)
1287 + (SvOOK(hv) ? sizeof(struct xpvhv_aux) : 0), char);
1293 Copy(&a[oldsize * sizeof(HE*)], &a[newsize * sizeof(HE*)], 1, struct xpvhv_aux);
1296 Newx(a, PERL_HV_ARRAY_ALLOC_BYTES(newsize)
1297 + (SvOOK(hv) ? sizeof(struct xpvhv_aux) : 0), char);
1302 Copy(HvARRAY(hv), a, oldsize * sizeof(HE*), char);
1304 Copy(HvAUX(hv), &a[newsize * sizeof(HE*)], 1, struct xpvhv_aux);
1306 Safefree(HvARRAY(hv));
1309 Zero(&a[oldsize * sizeof(HE*)], (newsize-oldsize) * sizeof(HE*), char); /* zero 2nd half*/
1312 Newxz(a, PERL_HV_ARRAY_ALLOC_BYTES(newsize), char);
1314 xhv->xhv_max = --newsize; /* HvMAX(hv) = --newsize */
1315 HvARRAY(hv) = (HE **) a;
1316 if (!xhv->xhv_keys /* !HvTOTALKEYS(hv) */) /* skip rest if no entries */
1320 for (i=0; i<oldsize; i++,aep++) {
1324 if (!entry) /* non-existent */
1327 register I32 j = (HeHASH(entry) & newsize);
1331 *oentry = HeNEXT(entry);
1332 HeNEXT(entry) = aep[j];
1336 oentry = &HeNEXT(entry);
1343 Perl_newHVhv(pTHX_ HV *ohv)
1346 HV * const hv = newHV();
1349 if (!ohv || !HvTOTALKEYS(ohv))
1351 hv_max = HvMAX(ohv);
1353 if (!SvMAGICAL((const SV *)ohv)) {
1354 /* It's an ordinary hash, so copy it fast. AMS 20010804 */
1356 const bool shared = !!HvSHAREKEYS(ohv);
1357 HE **ents, ** const oents = (HE **)HvARRAY(ohv);
1359 Newx(a, PERL_HV_ARRAY_ALLOC_BYTES(hv_max+1), char);
1362 /* In each bucket... */
1363 for (i = 0; i <= hv_max; i++) {
1365 HE *oent = oents[i];
1372 /* Copy the linked list of entries. */
1373 for (; oent; oent = HeNEXT(oent)) {
1374 const U32 hash = HeHASH(oent);
1375 const char * const key = HeKEY(oent);
1376 const STRLEN len = HeKLEN(oent);
1377 const int flags = HeKFLAGS(oent);
1378 HE * const ent = new_HE();
1379 SV *const val = HeVAL(oent);
1381 HeVAL(ent) = SvIMMORTAL(val) ? val : newSVsv(val);
1383 = shared ? share_hek_flags(key, len, hash, flags)
1384 : save_hek_flags(key, len, hash, flags);
1395 HvTOTALKEYS(hv) = HvTOTALKEYS(ohv);
1399 /* Iterate over ohv, copying keys and values one at a time. */
1401 const I32 riter = HvRITER_get(ohv);
1402 HE * const eiter = HvEITER_get(ohv);
1403 STRLEN hv_fill = HvFILL(ohv);
1405 /* Can we use fewer buckets? (hv_max is always 2^n-1) */
1406 while (hv_max && hv_max + 1 >= hv_fill * 2)
1407 hv_max = hv_max / 2;
1411 while ((entry = hv_iternext_flags(ohv, 0))) {
1412 SV *const val = HeVAL(entry);
1413 (void)hv_store_flags(hv, HeKEY(entry), HeKLEN(entry),
1414 SvIMMORTAL(val) ? val : newSVsv(val),
1415 HeHASH(entry), HeKFLAGS(entry));
1417 HvRITER_set(ohv, riter);
1418 HvEITER_set(ohv, eiter);
1425 =for apidoc Am|HV *|hv_copy_hints_hv|HV *ohv
1427 A specialised version of L</newHVhv> for copying C<%^H>. I<ohv> must be
1428 a pointer to a hash (which may have C<%^H> magic, but should be generally
1429 non-magical), or C<NULL> (interpreted as an empty hash). The content
1430 of I<ohv> is copied to a new hash, which has the C<%^H>-specific magic
1431 added to it. A pointer to the new hash is returned.
1437 Perl_hv_copy_hints_hv(pTHX_ HV *const ohv)
1439 HV * const hv = newHV();
1441 if (ohv && HvTOTALKEYS(ohv)) {
1442 STRLEN hv_max = HvMAX(ohv);
1443 STRLEN hv_fill = HvFILL(ohv);
1445 const I32 riter = HvRITER_get(ohv);
1446 HE * const eiter = HvEITER_get(ohv);
1448 while (hv_max && hv_max + 1 >= hv_fill * 2)
1449 hv_max = hv_max / 2;
1453 while ((entry = hv_iternext_flags(ohv, 0))) {
1454 SV *const sv = newSVsv(HeVAL(entry));
1455 SV *heksv = newSVhek(HeKEY_hek(entry));
1456 sv_magic(sv, NULL, PERL_MAGIC_hintselem,
1457 (char *)heksv, HEf_SVKEY);
1458 SvREFCNT_dec(heksv);
1459 (void)hv_store_flags(hv, HeKEY(entry), HeKLEN(entry),
1460 sv, HeHASH(entry), HeKFLAGS(entry));
1462 HvRITER_set(ohv, riter);
1463 HvEITER_set(ohv, eiter);
1465 hv_magic(hv, NULL, PERL_MAGIC_hints);
1470 Perl_hv_free_ent(pTHX_ HV *hv, register HE *entry)
1475 PERL_ARGS_ASSERT_HV_FREE_ENT;
1480 if (val && isGV(val) && isGV_with_GP(val) && GvCVu(val) && HvENAME(hv))
1481 mro_method_changed_in(hv); /* deletion of method from stash */
1483 if (HeKLEN(entry) == HEf_SVKEY) {
1484 SvREFCNT_dec(HeKEY_sv(entry));
1485 Safefree(HeKEY_hek(entry));
1487 else if (HvSHAREKEYS(hv))
1488 unshare_hek(HeKEY_hek(entry));
1490 Safefree(HeKEY_hek(entry));
1496 Perl_hv_delayfree_ent(pTHX_ HV *hv, register HE *entry)
1500 PERL_ARGS_ASSERT_HV_DELAYFREE_ENT;
1504 /* SvREFCNT_inc to counter the SvREFCNT_dec in hv_free_ent */
1505 sv_2mortal(SvREFCNT_inc(HeVAL(entry))); /* free between statements */
1506 if (HeKLEN(entry) == HEf_SVKEY) {
1507 sv_2mortal(SvREFCNT_inc(HeKEY_sv(entry)));
1509 hv_free_ent(hv, entry);
1513 =for apidoc hv_clear
1515 Clears a hash, making it empty.
1521 Perl_hv_clear(pTHX_ HV *hv)
1524 register XPVHV* xhv;
1528 DEBUG_A(Perl_hv_assert(aTHX_ hv));
1530 xhv = (XPVHV*)SvANY(hv);
1532 if (SvREADONLY(hv) && HvARRAY(hv) != NULL) {
1533 /* restricted hash: convert all keys to placeholders */
1535 for (i = 0; i <= xhv->xhv_max; i++) {
1536 HE *entry = (HvARRAY(hv))[i];
1537 for (; entry; entry = HeNEXT(entry)) {
1538 /* not already placeholder */
1539 if (HeVAL(entry) != &PL_sv_placeholder) {
1540 if (HeVAL(entry) && SvREADONLY(HeVAL(entry))) {
1541 SV* const keysv = hv_iterkeysv(entry);
1543 "Attempt to delete readonly key '%"SVf"' from a restricted hash",
1546 SvREFCNT_dec(HeVAL(entry));
1547 HeVAL(entry) = &PL_sv_placeholder;
1548 HvPLACEHOLDERS(hv)++;
1556 HvPLACEHOLDERS_set(hv, 0);
1558 Zero(HvARRAY(hv), xhv->xhv_max+1 /* HvMAX(hv)+1 */, HE*);
1561 mg_clear(MUTABLE_SV(hv));
1563 HvHASKFLAGS_off(hv);
1568 mro_isa_changed_in(hv);
1569 HvEITER_set(hv, NULL);
1574 =for apidoc hv_clear_placeholders
1576 Clears any placeholders from a hash. If a restricted hash has any of its keys
1577 marked as readonly and the key is subsequently deleted, the key is not actually
1578 deleted but is marked by assigning it a value of &PL_sv_placeholder. This tags
1579 it so it will be ignored by future operations such as iterating over the hash,
1580 but will still allow the hash to have a value reassigned to the key at some
1581 future point. This function clears any such placeholder keys from the hash.
1582 See Hash::Util::lock_keys() for an example of its use.
1588 Perl_hv_clear_placeholders(pTHX_ HV *hv)
1591 const U32 items = (U32)HvPLACEHOLDERS_get(hv);
1593 PERL_ARGS_ASSERT_HV_CLEAR_PLACEHOLDERS;
1596 clear_placeholders(hv, items);
1600 S_clear_placeholders(pTHX_ HV *hv, U32 items)
1605 PERL_ARGS_ASSERT_CLEAR_PLACEHOLDERS;
1612 /* Loop down the linked list heads */
1614 HE **oentry = &(HvARRAY(hv))[i];
1617 while ((entry = *oentry)) {
1618 if (HeVAL(entry) == &PL_sv_placeholder) {
1619 *oentry = HeNEXT(entry);
1620 if (entry == HvEITER_get(hv))
1623 hv_free_ent(hv, entry);
1627 HvTOTALKEYS(hv) -= (IV)HvPLACEHOLDERS_get(hv);
1628 if (HvKEYS(hv) == 0)
1629 HvHASKFLAGS_off(hv);
1630 HvPLACEHOLDERS_set(hv, 0);
1634 oentry = &HeNEXT(entry);
1639 /* You can't get here, hence assertion should always fail. */
1640 assert (items == 0);
1645 S_hfreeentries(pTHX_ HV *hv)
1647 /* This is the array that we're going to restore */
1648 HE **const orig_array = HvARRAY(hv);
1649 HE **tmp_array = NULL;
1650 const bool has_aux = (SvOOK(hv) == SVf_OOK);
1651 struct xpvhv_aux * current_aux = NULL;
1654 const bool mpm = PL_phase != PERL_PHASE_DESTRUCT && HvENAME(hv);
1656 PERL_ARGS_ASSERT_HFREEENTRIES;
1661 /* orig_array remains unchanged throughout the loop. If after freeing all
1662 the entries it turns out that one of the little blighters has triggered
1663 an action that has caused HvARRAY to be re-allocated, then we set
1664 array to the new HvARRAY, and try again. */
1667 /* This is the one we're going to try to empty. First time round
1668 it's the original array. (Hopefully there will only be 1 time
1670 HE ** const array = HvARRAY(hv);
1673 struct xpvhv_aux *iter = SvOOK(hv) ? HvAUX(hv) : NULL;
1675 /* If there are no keys, we only need to free items in the aux
1676 structure and then exit the loop. */
1677 const bool empty = !((XPVHV*) SvANY(hv))->xhv_keys;
1679 /* make everyone else think the array is empty, so that the destructors
1680 * called for freed entries can't recursively mess with us */
1681 if (!empty) HvARRAY(hv) = NULL;
1687 SvFLAGS(hv) &= ~SVf_OOK; /* Goodbye, aux structure. */
1688 /* What aux structure? */
1689 /* (But we still have a pointer to it in iter.) */
1691 /* Copy the name and MRO stuff to a new aux structure
1693 if (iter->xhv_name_u.xhvnameu_name || iter->xhv_mro_meta) {
1694 struct xpvhv_aux * const newaux = hv_auxinit(hv);
1695 newaux->xhv_name_count = iter->xhv_name_count;
1696 if (newaux->xhv_name_count)
1697 newaux->xhv_name_u.xhvnameu_names
1698 = iter->xhv_name_u.xhvnameu_names;
1700 newaux->xhv_name_u.xhvnameu_name
1701 = iter->xhv_name_u.xhvnameu_name;
1703 iter->xhv_name_u.xhvnameu_name = NULL;
1704 newaux->xhv_mro_meta = iter->xhv_mro_meta;
1705 iter->xhv_mro_meta = NULL;
1708 /* Because we have taken xhv_name and xhv_mro_meta out, the
1709 only allocated pointers in the aux structure that might
1710 exist are the back-reference array and xhv_eiter.
1714 /* weak references: if called from sv_clear(), the backrefs
1715 * should already have been killed; if there are any left, its
1716 * because we're doing hv_clear() or hv_undef(), and the HV
1717 * will continue to live.
1718 * Because while freeing the entries we fake up a NULL HvARRAY
1719 * (and hence HvAUX), we need to store the backref array
1720 * somewhere else; but it still needs to be visible in case
1721 * any the things we free happen to call sv_del_backref().
1722 * We do this by storing it in magic instead.
1723 * If, during the entry freeing, a destructor happens to add
1724 * a new weak backref, then sv_add_backref will look in both
1725 * places (magic in HvAUX) for the AV, but will create a new
1726 * AV in HvAUX if it can't find one (if it finds it in magic,
1727 * it moves it back into HvAUX. So at the end of the iteration
1728 * we have to allow for this. */
1731 if (iter->xhv_backreferences) {
1732 if (SvTYPE(iter->xhv_backreferences) == SVt_PVAV) {
1733 /* The sv_magic will increase the reference count of the AV,
1734 so we need to drop it first. */
1735 SvREFCNT_dec(iter->xhv_backreferences);
1736 if (AvFILLp(iter->xhv_backreferences) == -1) {
1737 /* Turns out that the array is empty. Just free it. */
1738 SvREFCNT_dec(iter->xhv_backreferences);
1741 sv_magic(MUTABLE_SV(hv),
1742 MUTABLE_SV(iter->xhv_backreferences),
1743 PERL_MAGIC_backref, NULL, 0);
1748 sv_magic(MUTABLE_SV(hv), NULL, PERL_MAGIC_backref, NULL, 0);
1749 mg = mg_find(MUTABLE_SV(hv), PERL_MAGIC_backref);
1750 mg->mg_obj = (SV*)iter->xhv_backreferences;
1752 iter->xhv_backreferences = NULL;
1755 entry = iter->xhv_eiter; /* HvEITER(hv) */
1756 if (entry && HvLAZYDEL(hv)) { /* was deleted earlier? */
1758 hv_free_ent(hv, entry);
1760 iter->xhv_riter = -1; /* HvRITER(hv) = -1 */
1761 iter->xhv_eiter = NULL; /* HvEITER(hv) = NULL */
1763 /* There are now no allocated pointers in the aux structure
1764 unless the hash is empty. */
1767 /* If there are no keys, there is nothing left to free. */
1770 /* Since we have removed the HvARRAY (and possibly replaced it by
1771 calling hv_auxinit), set the number of keys accordingly. */
1772 ((XPVHV*) SvANY(hv))->xhv_keys = 0;
1775 /* Loop down the linked list heads */
1776 HE *entry = array[i];
1779 register HE * const oentry = entry;
1780 entry = HeNEXT(entry);
1782 mpm && HeVAL(oentry) && isGV(HeVAL(oentry)) &&
1783 GvHV(HeVAL(oentry)) && HvENAME(GvHV(HeVAL(oentry)))
1786 const char * const key = HePV(oentry,klen);
1787 if ((klen > 1 && key[klen-1]==':' && key[klen-2]==':')
1788 || (klen == 1 && key[0] == ':')) {
1790 NULL, GvHV(HeVAL(oentry)),
1791 (GV *)HeVAL(oentry), 0
1795 hv_free_ent(hv, oentry);
1799 /* As there are no allocated pointers in the aux structure, it's now
1800 safe to free the array we just cleaned up, if it's not the one we're
1801 going to put back. */
1802 if (array != orig_array) {
1807 /* Good. No-one added anything this time round. */
1811 if (--attempts == 0) {
1812 Perl_die(aTHX_ "panic: hfreeentries failed to free hash - something is repeatedly re-creating entries");
1816 /* If the array was not replaced, the rest does not apply. */
1817 if (HvARRAY(hv) == orig_array) return;
1819 /* Set aside the current array for now, in case we still need it. */
1820 if (SvOOK(hv)) current_aux = HvAUX(hv);
1822 tmp_array = HvARRAY(hv);
1824 HvARRAY(hv) = orig_array;
1826 if (has_aux && current_aux)
1827 SvFLAGS(hv) |= SVf_OOK;
1829 SvFLAGS(hv) &=~SVf_OOK;
1831 /* If the hash was actually a symbol table, put the name and MRO
1834 struct xpvhv_aux * const aux
1835 = SvOOK(hv) ? HvAUX(hv) : hv_auxinit(hv);
1836 aux->xhv_name_count = current_aux->xhv_name_count;
1837 if(aux->xhv_name_count)
1838 aux->xhv_name_u.xhvnameu_names
1839 = current_aux->xhv_name_u.xhvnameu_names;
1841 aux->xhv_name_u.xhvnameu_name
1842 = current_aux->xhv_name_u.xhvnameu_name;
1843 aux->xhv_mro_meta = current_aux->xhv_mro_meta;
1846 if (tmp_array) Safefree(tmp_array);
1850 =for apidoc hv_undef
1858 Perl_hv_undef_flags(pTHX_ HV *hv, U32 flags)
1861 register XPVHV* xhv;
1866 DEBUG_A(Perl_hv_assert(aTHX_ hv));
1867 xhv = (XPVHV*)SvANY(hv);
1869 /* The name must be deleted before the call to hfreeeeentries so that
1870 CVs are anonymised properly. But the effective name must be pre-
1871 served until after that call (and only deleted afterwards if the
1872 call originated from sv_clear). For stashes with one name that is
1873 both the canonical name and the effective name, hv_name_set has to
1874 allocate an array for storing the effective name. We can skip that
1875 during global destruction, as it does not matter where the CVs point
1876 if they will be freed anyway. */
1877 if (PL_phase != PERL_PHASE_DESTRUCT && (name = HvNAME(hv))) {
1879 (void)hv_delete(PL_stashcache, name, HvNAMELEN_get(hv), G_DISCARD);
1880 hv_name_set(hv, NULL, 0, 0);
1884 struct xpvhv_aux * const aux = HvAUX(hv);
1885 struct mro_meta *meta;
1886 bool zeroed = FALSE;
1888 if ((name = HvENAME_get(hv))) {
1889 if (PL_phase != PERL_PHASE_DESTRUCT) {
1890 /* This must come at this point in case
1891 mro_isa_changed_in dies. */
1892 Zero(HvARRAY(hv), xhv->xhv_max+1 /* HvMAX(hv)+1 */, HE*);
1895 mro_isa_changed_in(hv);
1899 PL_stashcache, name, HvENAMELEN_get(hv), G_DISCARD
1903 /* If this call originated from sv_clear, then we must check for
1904 * effective names that need freeing, as well as the usual name. */
1906 if (flags & HV_NAME_SETALL ? !!aux->xhv_name_u.xhvnameu_name : !!name) {
1907 if (name && PL_stashcache)
1908 (void)hv_delete(PL_stashcache, name, HvNAMELEN_get(hv), G_DISCARD);
1909 hv_name_set(hv, NULL, 0, flags);
1911 if((meta = aux->xhv_mro_meta)) {
1912 if (meta->mro_linear_all) {
1913 SvREFCNT_dec(MUTABLE_SV(meta->mro_linear_all));
1914 meta->mro_linear_all = NULL;
1915 /* This is just acting as a shortcut pointer. */
1916 meta->mro_linear_current = NULL;
1917 } else if (meta->mro_linear_current) {
1918 /* Only the current MRO is stored, so this owns the data.
1920 SvREFCNT_dec(meta->mro_linear_current);
1921 meta->mro_linear_current = NULL;
1923 if(meta->mro_nextmethod) SvREFCNT_dec(meta->mro_nextmethod);
1924 SvREFCNT_dec(meta->isa);
1926 aux->xhv_mro_meta = NULL;
1928 if (!aux->xhv_name_u.xhvnameu_name)
1929 SvFLAGS(hv) &= ~SVf_OOK;
1931 Zero(HvARRAY(hv), xhv->xhv_max+1 /* HvMAX(hv)+1 */, HE*);
1934 Safefree(HvARRAY(hv));
1935 xhv->xhv_max = 7; /* HvMAX(hv) = 7 (it's a normal hash) */
1938 HvPLACEHOLDERS_set(hv, 0);
1941 mg_clear(MUTABLE_SV(hv));
1947 Returns the number of hash buckets that happen to be in use. This function is
1948 wrapped by the macro C<HvFILL>.
1950 Previously this value was stored in the HV structure, rather than being
1951 calculated on demand.
1957 Perl_hv_fill(pTHX_ HV const *const hv)
1960 HE **ents = HvARRAY(hv);
1962 PERL_ARGS_ASSERT_HV_FILL;
1965 HE *const *const last = ents + HvMAX(hv);
1966 count = last + 1 - ents;
1971 } while (++ents <= last);
1976 static struct xpvhv_aux*
1977 S_hv_auxinit(HV *hv) {
1978 struct xpvhv_aux *iter;
1981 PERL_ARGS_ASSERT_HV_AUXINIT;
1984 Newxz(array, PERL_HV_ARRAY_ALLOC_BYTES(HvMAX(hv) + 1)
1985 + sizeof(struct xpvhv_aux), char);
1987 array = (char *) HvARRAY(hv);
1988 Renew(array, PERL_HV_ARRAY_ALLOC_BYTES(HvMAX(hv) + 1)
1989 + sizeof(struct xpvhv_aux), char);
1991 HvARRAY(hv) = (HE**) array;
1992 /* SvOOK_on(hv) attacks the IV flags. */
1993 SvFLAGS(hv) |= SVf_OOK;
1996 iter->xhv_riter = -1; /* HvRITER(hv) = -1 */
1997 iter->xhv_eiter = NULL; /* HvEITER(hv) = NULL */
1998 iter->xhv_name_u.xhvnameu_name = 0;
1999 iter->xhv_name_count = 0;
2000 iter->xhv_backreferences = 0;
2001 iter->xhv_mro_meta = NULL;
2006 =for apidoc hv_iterinit
2008 Prepares a starting point to traverse a hash table. Returns the number of
2009 keys in the hash (i.e. the same as C<HvKEYS(hv)>). The return value is
2010 currently only meaningful for hashes without tie magic.
2012 NOTE: Before version 5.004_65, C<hv_iterinit> used to return the number of
2013 hash buckets that happen to be in use. If you still need that esoteric
2014 value, you can get it through the macro C<HvFILL(hv)>.
2021 Perl_hv_iterinit(pTHX_ HV *hv)
2023 PERL_ARGS_ASSERT_HV_ITERINIT;
2025 /* FIXME: Are we not NULL, or do we croak? Place bets now! */
2028 Perl_croak(aTHX_ "Bad hash");
2031 struct xpvhv_aux * const iter = HvAUX(hv);
2032 HE * const entry = iter->xhv_eiter; /* HvEITER(hv) */
2033 if (entry && HvLAZYDEL(hv)) { /* was deleted earlier? */
2035 hv_free_ent(hv, entry);
2037 iter->xhv_riter = -1; /* HvRITER(hv) = -1 */
2038 iter->xhv_eiter = NULL; /* HvEITER(hv) = NULL */
2043 /* used to be xhv->xhv_fill before 5.004_65 */
2044 return HvTOTALKEYS(hv);
2048 Perl_hv_riter_p(pTHX_ HV *hv) {
2049 struct xpvhv_aux *iter;
2051 PERL_ARGS_ASSERT_HV_RITER_P;
2054 Perl_croak(aTHX_ "Bad hash");
2056 iter = SvOOK(hv) ? HvAUX(hv) : hv_auxinit(hv);
2057 return &(iter->xhv_riter);
2061 Perl_hv_eiter_p(pTHX_ HV *hv) {
2062 struct xpvhv_aux *iter;
2064 PERL_ARGS_ASSERT_HV_EITER_P;
2067 Perl_croak(aTHX_ "Bad hash");
2069 iter = SvOOK(hv) ? HvAUX(hv) : hv_auxinit(hv);
2070 return &(iter->xhv_eiter);
2074 Perl_hv_riter_set(pTHX_ HV *hv, I32 riter) {
2075 struct xpvhv_aux *iter;
2077 PERL_ARGS_ASSERT_HV_RITER_SET;
2080 Perl_croak(aTHX_ "Bad hash");
2088 iter = hv_auxinit(hv);
2090 iter->xhv_riter = riter;
2094 Perl_hv_eiter_set(pTHX_ HV *hv, HE *eiter) {
2095 struct xpvhv_aux *iter;
2097 PERL_ARGS_ASSERT_HV_EITER_SET;
2100 Perl_croak(aTHX_ "Bad hash");
2105 /* 0 is the default so don't go malloc()ing a new structure just to
2110 iter = hv_auxinit(hv);
2112 iter->xhv_eiter = eiter;
2116 Perl_hv_name_set(pTHX_ HV *hv, const char *name, U32 len, U32 flags)
2119 struct xpvhv_aux *iter;
2123 PERL_ARGS_ASSERT_HV_NAME_SET;
2124 PERL_UNUSED_ARG(flags);
2127 Perl_croak(aTHX_ "panic: hv name too long (%"UVuf")", (UV) len);
2131 if (iter->xhv_name_u.xhvnameu_name) {
2132 if(iter->xhv_name_count) {
2133 if(flags & HV_NAME_SETALL) {
2134 HEK ** const name = HvAUX(hv)->xhv_name_u.xhvnameu_names;
2135 HEK **hekp = name + (
2136 iter->xhv_name_count < 0
2137 ? -iter->xhv_name_count
2138 : iter->xhv_name_count
2140 while(hekp-- > name+1)
2141 unshare_hek_or_pvn(*hekp, 0, 0, 0);
2142 /* The first elem may be null. */
2143 if(*name) unshare_hek_or_pvn(*name, 0, 0, 0);
2145 spot = &iter->xhv_name_u.xhvnameu_name;
2146 iter->xhv_name_count = 0;
2149 if(iter->xhv_name_count > 0) {
2150 /* shift some things over */
2152 iter->xhv_name_u.xhvnameu_names, iter->xhv_name_count + 1, HEK *
2154 spot = iter->xhv_name_u.xhvnameu_names;
2155 spot[iter->xhv_name_count] = spot[1];
2157 iter->xhv_name_count = -(iter->xhv_name_count + 1);
2159 else if(*(spot = iter->xhv_name_u.xhvnameu_names)) {
2160 unshare_hek_or_pvn(*spot, 0, 0, 0);
2164 else if (flags & HV_NAME_SETALL) {
2165 unshare_hek_or_pvn(iter->xhv_name_u.xhvnameu_name, 0, 0, 0);
2166 spot = &iter->xhv_name_u.xhvnameu_name;
2169 HEK * const existing_name = iter->xhv_name_u.xhvnameu_name;
2170 Newx(iter->xhv_name_u.xhvnameu_names, 2, HEK *);
2171 iter->xhv_name_count = -2;
2172 spot = iter->xhv_name_u.xhvnameu_names;
2173 spot[1] = existing_name;
2176 else { spot = &iter->xhv_name_u.xhvnameu_name; iter->xhv_name_count = 0; }
2181 iter = hv_auxinit(hv);
2182 spot = &iter->xhv_name_u.xhvnameu_name;
2184 PERL_HASH(hash, name, len);
2185 *spot = name ? share_hek(name, len, hash) : NULL;
2189 =for apidoc hv_ename_add
2191 Adds a name to a stash's internal list of effective names. See
2194 This is called when a stash is assigned to a new location in the symbol
2201 Perl_hv_ename_add(pTHX_ HV *hv, const char *name, U32 len, U32 flags)
2204 struct xpvhv_aux *aux = SvOOK(hv) ? HvAUX(hv) : hv_auxinit(hv);
2207 PERL_ARGS_ASSERT_HV_ENAME_ADD;
2208 PERL_UNUSED_ARG(flags);
2211 Perl_croak(aTHX_ "panic: hv name too long (%"UVuf")", (UV) len);
2213 PERL_HASH(hash, name, len);
2215 if (aux->xhv_name_count) {
2216 HEK ** const xhv_name = aux->xhv_name_u.xhvnameu_names;
2217 I32 count = aux->xhv_name_count;
2218 HEK **hekp = xhv_name + (count < 0 ? -count : count);
2219 while (hekp-- > xhv_name)
2221 HEK_LEN(*hekp) == (I32)len && memEQ(HEK_KEY(*hekp), name, len)
2223 if (hekp == xhv_name && count < 0)
2224 aux->xhv_name_count = -count;
2227 if (count < 0) aux->xhv_name_count--, count = -count;
2228 else aux->xhv_name_count++;
2229 Renew(aux->xhv_name_u.xhvnameu_names, count + 1, HEK *);
2230 (aux->xhv_name_u.xhvnameu_names)[count] = share_hek(name, len, hash);
2233 HEK *existing_name = aux->xhv_name_u.xhvnameu_name;
2235 existing_name && HEK_LEN(existing_name) == (I32)len
2236 && memEQ(HEK_KEY(existing_name), name, len)
2238 Newx(aux->xhv_name_u.xhvnameu_names, 2, HEK *);
2239 aux->xhv_name_count = existing_name ? 2 : -2;
2240 *aux->xhv_name_u.xhvnameu_names = existing_name;
2241 (aux->xhv_name_u.xhvnameu_names)[1] = share_hek(name, len, hash);
2246 =for apidoc hv_ename_delete
2248 Removes a name from a stash's internal list of effective names. If this is
2249 the name returned by C<HvENAME>, then another name in the list will take
2250 its place (C<HvENAME> will use it).
2252 This is called when a stash is deleted from the symbol table.
2258 Perl_hv_ename_delete(pTHX_ HV *hv, const char *name, U32 len, U32 flags)
2261 struct xpvhv_aux *aux;
2263 PERL_ARGS_ASSERT_HV_ENAME_DELETE;
2264 PERL_UNUSED_ARG(flags);
2267 Perl_croak(aTHX_ "panic: hv name too long (%"UVuf")", (UV) len);
2269 if (!SvOOK(hv)) return;
2272 if (!aux->xhv_name_u.xhvnameu_name) return;
2274 if (aux->xhv_name_count) {
2275 HEK ** const namep = aux->xhv_name_u.xhvnameu_names;
2276 I32 const count = aux->xhv_name_count;
2277 HEK **victim = namep + (count < 0 ? -count : count);
2278 while (victim-- > namep + 1)
2280 HEK_LEN(*victim) == (I32)len
2281 && memEQ(HEK_KEY(*victim), name, len)
2283 unshare_hek_or_pvn(*victim, 0, 0, 0);
2284 if (count < 0) ++aux->xhv_name_count;
2285 else --aux->xhv_name_count;
2287 (aux->xhv_name_count == 1 || aux->xhv_name_count == -1)
2289 ) { /* if there are none left */
2291 aux->xhv_name_u.xhvnameu_names = NULL;
2292 aux->xhv_name_count = 0;
2295 /* Move the last one back to fill the empty slot. It
2296 does not matter what order they are in. */
2297 *victim = *(namep + (count < 0 ? -count : count) - 1);
2302 count > 0 && HEK_LEN(*namep) == (I32)len
2303 && memEQ(HEK_KEY(*namep),name,len)
2305 aux->xhv_name_count = -count;
2309 HEK_LEN(aux->xhv_name_u.xhvnameu_name) == (I32)len
2310 && memEQ(HEK_KEY(aux->xhv_name_u.xhvnameu_name), name, len)
2312 HEK * const namehek = aux->xhv_name_u.xhvnameu_name;
2313 Newx(aux->xhv_name_u.xhvnameu_names, 1, HEK *);
2314 *aux->xhv_name_u.xhvnameu_names = namehek;
2315 aux->xhv_name_count = -1;
2320 Perl_hv_backreferences_p(pTHX_ HV *hv) {
2321 struct xpvhv_aux * const iter = SvOOK(hv) ? HvAUX(hv) : hv_auxinit(hv);
2323 PERL_ARGS_ASSERT_HV_BACKREFERENCES_P;
2324 PERL_UNUSED_CONTEXT;
2326 return &(iter->xhv_backreferences);
2330 Perl_hv_kill_backrefs(pTHX_ HV *hv) {
2333 PERL_ARGS_ASSERT_HV_KILL_BACKREFS;
2338 av = HvAUX(hv)->xhv_backreferences;
2341 HvAUX(hv)->xhv_backreferences = 0;
2342 Perl_sv_kill_backrefs(aTHX_ MUTABLE_SV(hv), av);
2343 if (SvTYPE(av) == SVt_PVAV)
2349 hv_iternext is implemented as a macro in hv.h
2351 =for apidoc hv_iternext
2353 Returns entries from a hash iterator. See C<hv_iterinit>.
2355 You may call C<hv_delete> or C<hv_delete_ent> on the hash entry that the
2356 iterator currently points to, without losing your place or invalidating your
2357 iterator. Note that in this case the current entry is deleted from the hash
2358 with your iterator holding the last reference to it. Your iterator is flagged
2359 to free the entry on the next call to C<hv_iternext>, so you must not discard
2360 your iterator immediately else the entry will leak - call C<hv_iternext> to
2361 trigger the resource deallocation.
2363 =for apidoc hv_iternext_flags
2365 Returns entries from a hash iterator. See C<hv_iterinit> and C<hv_iternext>.
2366 The C<flags> value will normally be zero; if HV_ITERNEXT_WANTPLACEHOLDERS is
2367 set the placeholders keys (for restricted hashes) will be returned in addition
2368 to normal keys. By default placeholders are automatically skipped over.
2369 Currently a placeholder is implemented with a value that is
2370 C<&Perl_sv_placeholder>. Note that the implementation of placeholders and
2371 restricted hashes may change, and the implementation currently is
2372 insufficiently abstracted for any change to be tidy.
2378 Perl_hv_iternext_flags(pTHX_ HV *hv, I32 flags)
2381 register XPVHV* xhv;
2385 struct xpvhv_aux *iter;
2387 PERL_ARGS_ASSERT_HV_ITERNEXT_FLAGS;
2390 Perl_croak(aTHX_ "Bad hash");
2392 xhv = (XPVHV*)SvANY(hv);
2395 /* Too many things (well, pp_each at least) merrily assume that you can
2396 call iv_iternext without calling hv_iterinit, so we'll have to deal
2402 oldentry = entry = iter->xhv_eiter; /* HvEITER(hv) */
2403 if (SvMAGICAL(hv) && SvRMAGICAL(hv)) {
2404 if ( ( mg = mg_find((const SV *)hv, PERL_MAGIC_tied) ) ) {
2405 SV * const key = sv_newmortal();
2407 sv_setsv(key, HeSVKEY_force(entry));
2408 SvREFCNT_dec(HeSVKEY(entry)); /* get rid of previous key */
2414 /* one HE per MAGICAL hash */
2415 iter->xhv_eiter = entry = new_HE(); /* HvEITER(hv) = new_HE() */
2417 Newxz(k, HEK_BASESIZE + sizeof(const SV *), char);
2419 HeKEY_hek(entry) = hek;
2420 HeKLEN(entry) = HEf_SVKEY;
2422 magic_nextpack(MUTABLE_SV(hv),mg,key);
2424 /* force key to stay around until next time */
2425 HeSVKEY_set(entry, SvREFCNT_inc_simple_NN(key));
2426 return entry; /* beware, hent_val is not set */
2428 SvREFCNT_dec(HeVAL(entry));
2429 Safefree(HeKEY_hek(entry));
2431 iter->xhv_eiter = NULL; /* HvEITER(hv) = NULL */
2435 #if defined(DYNAMIC_ENV_FETCH) && !defined(__riscos__) /* set up %ENV for iteration */
2436 if (!entry && SvRMAGICAL((const SV *)hv)
2437 && mg_find((const SV *)hv, PERL_MAGIC_env)) {
2440 /* The prime_env_iter() on VMS just loaded up new hash values
2441 * so the iteration count needs to be reset back to the beginning
2445 oldentry = entry = iter->xhv_eiter; /* HvEITER(hv) */
2450 /* hv_iterint now ensures this. */
2451 assert (HvARRAY(hv));
2453 /* At start of hash, entry is NULL. */
2456 entry = HeNEXT(entry);
2457 if (!(flags & HV_ITERNEXT_WANTPLACEHOLDERS)) {
2459 * Skip past any placeholders -- don't want to include them in
2462 while (entry && HeVAL(entry) == &PL_sv_placeholder) {
2463 entry = HeNEXT(entry);
2468 /* Skip the entire loop if the hash is empty. */
2469 if ((flags & HV_ITERNEXT_WANTPLACEHOLDERS)
2470 ? HvTOTALKEYS(hv) : HvUSEDKEYS(hv)) {
2472 /* OK. Come to the end of the current list. Grab the next one. */
2474 iter->xhv_riter++; /* HvRITER(hv)++ */
2475 if (iter->xhv_riter > (I32)xhv->xhv_max /* HvRITER(hv) > HvMAX(hv) */) {
2476 /* There is no next one. End of the hash. */
2477 iter->xhv_riter = -1; /* HvRITER(hv) = -1 */
2480 entry = (HvARRAY(hv))[iter->xhv_riter];
2482 if (!(flags & HV_ITERNEXT_WANTPLACEHOLDERS)) {
2483 /* If we have an entry, but it's a placeholder, don't count it.
2485 while (entry && HeVAL(entry) == &PL_sv_placeholder)
2486 entry = HeNEXT(entry);
2488 /* Will loop again if this linked list starts NULL
2489 (for HV_ITERNEXT_WANTPLACEHOLDERS)
2490 or if we run through it and find only placeholders. */
2494 if (oldentry && HvLAZYDEL(hv)) { /* was deleted earlier? */
2496 hv_free_ent(hv, oldentry);
2499 /*if (HvREHASH(hv) && entry && !HeKREHASH(entry))
2500 PerlIO_printf(PerlIO_stderr(), "Awooga %p %p\n", (void*)hv, (void*)entry);*/
2502 iter->xhv_eiter = entry; /* HvEITER(hv) = entry */
2507 =for apidoc hv_iterkey
2509 Returns the key from the current position of the hash iterator. See
2516 Perl_hv_iterkey(pTHX_ register HE *entry, I32 *retlen)
2518 PERL_ARGS_ASSERT_HV_ITERKEY;
2520 if (HeKLEN(entry) == HEf_SVKEY) {
2522 char * const p = SvPV(HeKEY_sv(entry), len);
2527 *retlen = HeKLEN(entry);
2528 return HeKEY(entry);
2532 /* unlike hv_iterval(), this always returns a mortal copy of the key */
2534 =for apidoc hv_iterkeysv
2536 Returns the key as an C<SV*> from the current position of the hash
2537 iterator. The return value will always be a mortal copy of the key. Also
2544 Perl_hv_iterkeysv(pTHX_ register HE *entry)
2546 PERL_ARGS_ASSERT_HV_ITERKEYSV;
2548 return sv_2mortal(newSVhek(HeKEY_hek(entry)));
2552 =for apidoc hv_iterval
2554 Returns the value from the current position of the hash iterator. See
2561 Perl_hv_iterval(pTHX_ HV *hv, register HE *entry)
2563 PERL_ARGS_ASSERT_HV_ITERVAL;
2565 if (SvRMAGICAL(hv)) {
2566 if (mg_find((const SV *)hv, PERL_MAGIC_tied)) {
2567 SV* const sv = sv_newmortal();
2568 if (HeKLEN(entry) == HEf_SVKEY)
2569 mg_copy(MUTABLE_SV(hv), sv, (char*)HeKEY_sv(entry), HEf_SVKEY);
2571 mg_copy(MUTABLE_SV(hv), sv, HeKEY(entry), HeKLEN(entry));
2575 return HeVAL(entry);
2579 =for apidoc hv_iternextsv
2581 Performs an C<hv_iternext>, C<hv_iterkey>, and C<hv_iterval> in one
2588 Perl_hv_iternextsv(pTHX_ HV *hv, char **key, I32 *retlen)
2590 HE * const he = hv_iternext_flags(hv, 0);
2592 PERL_ARGS_ASSERT_HV_ITERNEXTSV;
2596 *key = hv_iterkey(he, retlen);
2597 return hv_iterval(hv, he);
2604 =for apidoc hv_magic
2606 Adds magic to a hash. See C<sv_magic>.
2611 /* possibly free a shared string if no one has access to it
2612 * len and hash must both be valid for str.
2615 Perl_unsharepvn(pTHX_ const char *str, I32 len, U32 hash)
2617 unshare_hek_or_pvn (NULL, str, len, hash);
2622 Perl_unshare_hek(pTHX_ HEK *hek)
2625 unshare_hek_or_pvn(hek, NULL, 0, 0);
2628 /* possibly free a shared string if no one has access to it
2629 hek if non-NULL takes priority over the other 3, else str, len and hash
2630 are used. If so, len and hash must both be valid for str.
2633 S_unshare_hek_or_pvn(pTHX_ const HEK *hek, const char *str, I32 len, U32 hash)
2636 register XPVHV* xhv;
2638 register HE **oentry;
2640 bool is_utf8 = FALSE;
2642 const char * const save = str;
2643 struct shared_he *he = NULL;
2646 /* Find the shared he which is just before us in memory. */
2647 he = (struct shared_he *)(((char *)hek)
2648 - STRUCT_OFFSET(struct shared_he,
2651 /* Assert that the caller passed us a genuine (or at least consistent)
2653 assert (he->shared_he_he.hent_hek == hek);
2655 if (he->shared_he_he.he_valu.hent_refcount - 1) {
2656 --he->shared_he_he.he_valu.hent_refcount;
2660 hash = HEK_HASH(hek);
2661 } else if (len < 0) {
2662 STRLEN tmplen = -len;
2664 /* See the note in hv_fetch(). --jhi */
2665 str = (char*)bytes_from_utf8((U8*)str, &tmplen, &is_utf8);
2668 k_flags = HVhek_UTF8;
2670 k_flags |= HVhek_WASUTF8 | HVhek_FREEKEY;
2673 /* what follows was the moral equivalent of:
2674 if ((Svp = hv_fetch(PL_strtab, tmpsv, FALSE, hash))) {
2676 hv_delete(PL_strtab, str, len, G_DISCARD, hash);
2678 xhv = (XPVHV*)SvANY(PL_strtab);
2679 /* assert(xhv_array != 0) */
2680 first = oentry = &(HvARRAY(PL_strtab))[hash & (I32) HvMAX(PL_strtab)];
2682 const HE *const he_he = &(he->shared_he_he);
2683 for (entry = *oentry; entry; oentry = &HeNEXT(entry), entry = *oentry) {
2688 const int flags_masked = k_flags & HVhek_MASK;
2689 for (entry = *oentry; entry; oentry = &HeNEXT(entry), entry = *oentry) {
2690 if (HeHASH(entry) != hash) /* strings can't be equal */
2692 if (HeKLEN(entry) != len)
2694 if (HeKEY(entry) != str && memNE(HeKEY(entry),str,len)) /* is this it? */
2696 if (HeKFLAGS(entry) != flags_masked)
2703 if (--entry->he_valu.hent_refcount == 0) {
2704 *oentry = HeNEXT(entry);
2706 xhv->xhv_keys--; /* HvTOTALKEYS(hv)-- */
2711 Perl_ck_warner_d(aTHX_ packWARN(WARN_INTERNAL),
2712 "Attempt to free non-existent shared string '%s'%s"
2714 hek ? HEK_KEY(hek) : str,
2715 ((k_flags & HVhek_UTF8) ? " (utf8)" : "") pTHX__VALUE);
2716 if (k_flags & HVhek_FREEKEY)
2720 /* get a (constant) string ptr from the global string table
2721 * string will get added if it is not already there.
2722 * len and hash must both be valid for str.
2725 Perl_share_hek(pTHX_ const char *str, I32 len, register U32 hash)
2727 bool is_utf8 = FALSE;
2729 const char * const save = str;
2731 PERL_ARGS_ASSERT_SHARE_HEK;
2734 STRLEN tmplen = -len;
2736 /* See the note in hv_fetch(). --jhi */
2737 str = (char*)bytes_from_utf8((U8*)str, &tmplen, &is_utf8);
2739 /* If we were able to downgrade here, then than means that we were passed
2740 in a key which only had chars 0-255, but was utf8 encoded. */
2743 /* If we found we were able to downgrade the string to bytes, then
2744 we should flag that it needs upgrading on keys or each. Also flag
2745 that we need share_hek_flags to free the string. */
2747 flags |= HVhek_WASUTF8 | HVhek_FREEKEY;
2750 return share_hek_flags (str, len, hash, flags);
2754 S_share_hek_flags(pTHX_ const char *str, I32 len, register U32 hash, int flags)
2758 const int flags_masked = flags & HVhek_MASK;
2759 const U32 hindex = hash & (I32) HvMAX(PL_strtab);
2760 register XPVHV * const xhv = (XPVHV*)SvANY(PL_strtab);
2762 PERL_ARGS_ASSERT_SHARE_HEK_FLAGS;
2764 /* what follows is the moral equivalent of:
2766 if (!(Svp = hv_fetch(PL_strtab, str, len, FALSE)))
2767 hv_store(PL_strtab, str, len, NULL, hash);
2769 Can't rehash the shared string table, so not sure if it's worth
2770 counting the number of entries in the linked list
2773 /* assert(xhv_array != 0) */
2774 entry = (HvARRAY(PL_strtab))[hindex];
2775 for (;entry; entry = HeNEXT(entry)) {
2776 if (HeHASH(entry) != hash) /* strings can't be equal */
2778 if (HeKLEN(entry) != len)
2780 if (HeKEY(entry) != str && memNE(HeKEY(entry),str,len)) /* is this it? */
2782 if (HeKFLAGS(entry) != flags_masked)
2788 /* What used to be head of the list.
2789 If this is NULL, then we're the first entry for this slot, which
2790 means we need to increate fill. */
2791 struct shared_he *new_entry;
2794 HE **const head = &HvARRAY(PL_strtab)[hindex];
2795 HE *const next = *head;
2797 /* We don't actually store a HE from the arena and a regular HEK.
2798 Instead we allocate one chunk of memory big enough for both,
2799 and put the HEK straight after the HE. This way we can find the
2800 HEK directly from the HE.
2803 Newx(k, STRUCT_OFFSET(struct shared_he,
2804 shared_he_hek.hek_key[0]) + len + 2, char);
2805 new_entry = (struct shared_he *)k;
2806 entry = &(new_entry->shared_he_he);
2807 hek = &(new_entry->shared_he_hek);
2809 Copy(str, HEK_KEY(hek), len, char);
2810 HEK_KEY(hek)[len] = 0;
2812 HEK_HASH(hek) = hash;
2813 HEK_FLAGS(hek) = (unsigned char)flags_masked;
2815 /* Still "point" to the HEK, so that other code need not know what
2817 HeKEY_hek(entry) = hek;
2818 entry->he_valu.hent_refcount = 0;
2819 HeNEXT(entry) = next;
2822 xhv->xhv_keys++; /* HvTOTALKEYS(hv)++ */
2823 if (!next) { /* initial entry? */
2824 } else if (xhv->xhv_keys > xhv->xhv_max /* HvKEYS(hv) > HvMAX(hv) */) {
2829 ++entry->he_valu.hent_refcount;
2831 if (flags & HVhek_FREEKEY)
2834 return HeKEY_hek(entry);
2838 Perl_hv_placeholders_p(pTHX_ HV *hv)
2841 MAGIC *mg = mg_find((const SV *)hv, PERL_MAGIC_rhash);
2843 PERL_ARGS_ASSERT_HV_PLACEHOLDERS_P;
2846 mg = sv_magicext(MUTABLE_SV(hv), 0, PERL_MAGIC_rhash, 0, 0, 0);
2849 Perl_die(aTHX_ "panic: hv_placeholders_p");
2852 return &(mg->mg_len);
2857 Perl_hv_placeholders_get(pTHX_ const HV *hv)
2860 MAGIC * const mg = mg_find((const SV *)hv, PERL_MAGIC_rhash);
2862 PERL_ARGS_ASSERT_HV_PLACEHOLDERS_GET;
2864 return mg ? mg->mg_len : 0;
2868 Perl_hv_placeholders_set(pTHX_ HV *hv, I32 ph)
2871 MAGIC * const mg = mg_find((const SV *)hv, PERL_MAGIC_rhash);
2873 PERL_ARGS_ASSERT_HV_PLACEHOLDERS_SET;
2878 if (!sv_magicext(MUTABLE_SV(hv), 0, PERL_MAGIC_rhash, 0, 0, ph))
2879 Perl_die(aTHX_ "panic: hv_placeholders_set");
2881 /* else we don't need to add magic to record 0 placeholders. */
2885 S_refcounted_he_value(pTHX_ const struct refcounted_he *he)
2890 PERL_ARGS_ASSERT_REFCOUNTED_HE_VALUE;
2892 switch(he->refcounted_he_data[0] & HVrhek_typemask) {
2897 value = &PL_sv_placeholder;
2900 value = newSViv(he->refcounted_he_val.refcounted_he_u_iv);
2903 value = newSVuv(he->refcounted_he_val.refcounted_he_u_uv);
2906 case HVrhek_PV_UTF8:
2907 /* Create a string SV that directly points to the bytes in our
2909 value = newSV_type(SVt_PV);
2910 SvPV_set(value, (char *) he->refcounted_he_data + 1);
2911 SvCUR_set(value, he->refcounted_he_val.refcounted_he_u_len);
2912 /* This stops anything trying to free it */
2913 SvLEN_set(value, 0);
2915 SvREADONLY_on(value);
2916 if ((he->refcounted_he_data[0] & HVrhek_typemask) == HVrhek_PV_UTF8)
2920 Perl_croak(aTHX_ "panic: refcounted_he_value bad flags %"UVxf,
2921 (UV)he->refcounted_he_data[0]);
2927 =for apidoc m|HV *|refcounted_he_chain_2hv|const struct refcounted_he *c|U32 flags
2929 Generates and returns a C<HV *> representing the content of a
2930 C<refcounted_he> chain.
2931 I<flags> is currently unused and must be zero.
2936 Perl_refcounted_he_chain_2hv(pTHX_ const struct refcounted_he *chain, U32 flags)
2940 U32 placeholders, max;
2943 Perl_croak(aTHX_ "panic: refcounted_he_chain_2hv bad flags %"UVxf,
2946 /* We could chase the chain once to get an idea of the number of keys,
2947 and call ksplit. But for now we'll make a potentially inefficient
2948 hash with only 8 entries in its array. */
2953 Newxz(array, PERL_HV_ARRAY_ALLOC_BYTES(max + 1), char);
2954 HvARRAY(hv) = (HE**)array;
2960 U32 hash = chain->refcounted_he_hash;
2962 U32 hash = HEK_HASH(chain->refcounted_he_hek);
2964 HE **oentry = &((HvARRAY(hv))[hash & max]);
2965 HE *entry = *oentry;
2968 for (; entry; entry = HeNEXT(entry)) {
2969 if (HeHASH(entry) == hash) {
2970 /* We might have a duplicate key here. If so, entry is older
2971 than the key we've already put in the hash, so if they are
2972 the same, skip adding entry. */
2974 const STRLEN klen = HeKLEN(entry);
2975 const char *const key = HeKEY(entry);
2976 if (klen == chain->refcounted_he_keylen
2977 && (!!HeKUTF8(entry)
2978 == !!(chain->refcounted_he_data[0] & HVhek_UTF8))
2979 && memEQ(key, REF_HE_KEY(chain), klen))
2982 if (HeKEY_hek(entry) == chain->refcounted_he_hek)
2984 if (HeKLEN(entry) == HEK_LEN(chain->refcounted_he_hek)
2985 && HeKUTF8(entry) == HEK_UTF8(chain->refcounted_he_hek)
2986 && memEQ(HeKEY(entry), HEK_KEY(chain->refcounted_he_hek),
2997 = share_hek_flags(REF_HE_KEY(chain),
2998 chain->refcounted_he_keylen,
2999 chain->refcounted_he_hash,
3000 (chain->refcounted_he_data[0]
3001 & (HVhek_UTF8|HVhek_WASUTF8)));
3003 HeKEY_hek(entry) = share_hek_hek(chain->refcounted_he_hek);
3005 value = refcounted_he_value(chain);
3006 if (value == &PL_sv_placeholder)
3008 HeVAL(entry) = value;
3010 /* Link it into the chain. */
3011 HeNEXT(entry) = *oentry;
3017 chain = chain->refcounted_he_next;
3021 clear_placeholders(hv, placeholders);
3022 HvTOTALKEYS(hv) -= placeholders;
3025 /* We could check in the loop to see if we encounter any keys with key
3026 flags, but it's probably not worth it, as this per-hash flag is only
3027 really meant as an optimisation for things like Storable. */
3029 DEBUG_A(Perl_hv_assert(aTHX_ hv));
3035 =for apidoc m|SV *|refcounted_he_fetch_pvn|const struct refcounted_he *chain|const char *keypv|STRLEN keylen|U32 hash|U32 flags
3037 Search along a C<refcounted_he> chain for an entry with the key specified
3038 by I<keypv> and I<keylen>. If I<flags> has the C<REFCOUNTED_HE_KEY_UTF8>
3039 bit set, the key octets are interpreted as UTF-8, otherwise they
3040 are interpreted as Latin-1. I<hash> is a precomputed hash of the key
3041 string, or zero if it has not been precomputed. Returns a mortal scalar
3042 representing the value associated with the key, or C<&PL_sv_placeholder>
3043 if there is no value associated with the key.
3049 Perl_refcounted_he_fetch_pvn(pTHX_ const struct refcounted_he *chain,
3050 const char *keypv, STRLEN keylen, U32 hash, U32 flags)
3054 PERL_ARGS_ASSERT_REFCOUNTED_HE_FETCH_PVN;
3056 if (flags & ~REFCOUNTED_HE_KEY_UTF8)
3057 Perl_croak(aTHX_ "panic: refcounted_he_fetch_pvn bad flags %"UVxf,
3060 return &PL_sv_placeholder;
3061 if (flags & REFCOUNTED_HE_KEY_UTF8) {
3062 /* For searching purposes, canonicalise to Latin-1 where possible. */
3063 const char *keyend = keypv + keylen, *p;
3064 STRLEN nonascii_count = 0;
3065 for (p = keypv; p != keyend; p++) {
3068 if (!((c & 0xfe) == 0xc2 && ++p != keyend &&
3069 (((U8)*p) & 0xc0) == 0x80))
3070 goto canonicalised_key;
3074 if (nonascii_count) {
3076 const char *p = keypv, *keyend = keypv + keylen;
3077 keylen -= nonascii_count;
3078 Newx(q, keylen, char);
3081 for (; p != keyend; p++, q++) {
3084 ((c & 0x80) ? ((c & 0x03) << 6) | (((U8)*++p) & 0x3f) : c);
3087 flags &= ~REFCOUNTED_HE_KEY_UTF8;
3088 canonicalised_key: ;
3090 utf8_flag = (flags & REFCOUNTED_HE_KEY_UTF8) ? HVhek_UTF8 : 0;
3092 PERL_HASH(hash, keypv, keylen);
3094 for (; chain; chain = chain->refcounted_he_next) {
3097 hash == chain->refcounted_he_hash &&
3098 keylen == chain->refcounted_he_keylen &&
3099 memEQ(REF_HE_KEY(chain), keypv, keylen) &&
3100 utf8_flag == (chain->refcounted_he_data[0] & HVhek_UTF8)
3102 hash == HEK_HASH(chain->refcounted_he_hek) &&
3103 keylen == (STRLEN)HEK_LEN(chain->refcounted_he_hek) &&
3104 memEQ(HEK_KEY(chain->refcounted_he_hek), keypv, keylen) &&
3105 utf8_flag == (HEK_FLAGS(chain->refcounted_he_hek) & HVhek_UTF8)
3108 return sv_2mortal(refcounted_he_value(chain));
3110 return &PL_sv_placeholder;
3114 =for apidoc m|SV *|refcounted_he_fetch_pv|const struct refcounted_he *chain|const char *key|U32 hash|U32 flags
3116 Like L</refcounted_he_fetch_pvn>, but takes a nul-terminated string
3117 instead of a string/length pair.
3123 Perl_refcounted_he_fetch_pv(pTHX_ const struct refcounted_he *chain,
3124 const char *key, U32 hash, U32 flags)
3126 PERL_ARGS_ASSERT_REFCOUNTED_HE_FETCH_PV;
3127 return refcounted_he_fetch_pvn(chain, key, strlen(key), hash, flags);
3131 =for apidoc m|SV *|refcounted_he_fetch_sv|const struct refcounted_he *chain|SV *key|U32 hash|U32 flags
3133 Like L</refcounted_he_fetch_pvn>, but takes a Perl scalar instead of a
3140 Perl_refcounted_he_fetch_sv(pTHX_ const struct refcounted_he *chain,
3141 SV *key, U32 hash, U32 flags)
3145 PERL_ARGS_ASSERT_REFCOUNTED_HE_FETCH_SV;
3146 if (flags & REFCOUNTED_HE_KEY_UTF8)
3147 Perl_croak(aTHX_ "panic: refcounted_he_fetch_sv bad flags %"UVxf,
3149 keypv = SvPV_const(key, keylen);
3151 flags |= REFCOUNTED_HE_KEY_UTF8;
3152 if (!hash && SvIsCOW_shared_hash(key))
3153 hash = SvSHARED_HASH(key);
3154 return refcounted_he_fetch_pvn(chain, keypv, keylen, hash, flags);
3158 =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
3160 Creates a new C<refcounted_he>. This consists of a single key/value
3161 pair and a reference to an existing C<refcounted_he> chain (which may
3162 be empty), and thus forms a longer chain. When using the longer chain,
3163 the new key/value pair takes precedence over any entry for the same key
3164 further along the chain.
3166 The new key is specified by I<keypv> and I<keylen>. If I<flags> has
3167 the C<REFCOUNTED_HE_KEY_UTF8> bit set, the key octets are interpreted
3168 as UTF-8, otherwise they are interpreted as Latin-1. I<hash> is
3169 a precomputed hash of the key string, or zero if it has not been
3172 I<value> is the scalar value to store for this key. I<value> is copied
3173 by this function, which thus does not take ownership of any reference
3174 to it, and later changes to the scalar will not be reflected in the
3175 value visible in the C<refcounted_he>. Complex types of scalar will not
3176 be stored with referential integrity, but will be coerced to strings.
3177 I<value> may be either null or C<&PL_sv_placeholder> to indicate that no
3178 value is to be associated with the key; this, as with any non-null value,
3179 takes precedence over the existence of a value for the key further along
3182 I<parent> points to the rest of the C<refcounted_he> chain to be
3183 attached to the new C<refcounted_he>. This function takes ownership
3184 of one reference to I<parent>, and returns one reference to the new
3190 struct refcounted_he *
3191 Perl_refcounted_he_new_pvn(pTHX_ struct refcounted_he *parent,
3192 const char *keypv, STRLEN keylen, U32 hash, SV *value, U32 flags)
3195 STRLEN value_len = 0;
3196 const char *value_p = NULL;
3200 STRLEN key_offset = 1;
3201 struct refcounted_he *he;
3202 PERL_ARGS_ASSERT_REFCOUNTED_HE_NEW_PVN;
3204 if (!value || value == &PL_sv_placeholder) {
3205 value_type = HVrhek_delete;
3206 } else if (SvPOK(value)) {
3207 value_type = HVrhek_PV;
3208 } else if (SvIOK(value)) {
3209 value_type = SvUOK((const SV *)value) ? HVrhek_UV : HVrhek_IV;
3210 } else if (!SvOK(value)) {
3211 value_type = HVrhek_undef;
3213 value_type = HVrhek_PV;
3215 is_pv = value_type == HVrhek_PV;
3217 /* Do it this way so that the SvUTF8() test is after the SvPV, in case
3218 the value is overloaded, and doesn't yet have the UTF-8flag set. */
3219 value_p = SvPV_const(value, value_len);
3221 value_type = HVrhek_PV_UTF8;
3222 key_offset = value_len + 2;
3224 hekflags = value_type;
3226 if (flags & REFCOUNTED_HE_KEY_UTF8) {
3227 /* Canonicalise to Latin-1 where possible. */
3228 const char *keyend = keypv + keylen, *p;
3229 STRLEN nonascii_count = 0;
3230 for (p = keypv; p != keyend; p++) {
3233 if (!((c & 0xfe) == 0xc2 && ++p != keyend &&
3234 (((U8)*p) & 0xc0) == 0x80))
3235 goto canonicalised_key;
3239 if (nonascii_count) {
3241 const char *p = keypv, *keyend = keypv + keylen;
3242 keylen -= nonascii_count;
3243 Newx(q, keylen, char);
3246 for (; p != keyend; p++, q++) {
3249 ((c & 0x80) ? ((c & 0x03) << 6) | (((U8)*++p) & 0x3f) : c);
3252 flags &= ~REFCOUNTED_HE_KEY_UTF8;
3253 canonicalised_key: ;
3255 if (flags & REFCOUNTED_HE_KEY_UTF8)
3256 hekflags |= HVhek_UTF8;
3258 PERL_HASH(hash, keypv, keylen);
3261 he = (struct refcounted_he*)
3262 PerlMemShared_malloc(sizeof(struct refcounted_he) - 1
3266 he = (struct refcounted_he*)
3267 PerlMemShared_malloc(sizeof(struct refcounted_he) - 1
3271 he->refcounted_he_next = parent;
3274 Copy(value_p, he->refcounted_he_data + 1, value_len + 1, char);
3275 he->refcounted_he_val.refcounted_he_u_len = value_len;
3276 } else if (value_type == HVrhek_IV) {
3277 he->refcounted_he_val.refcounted_he_u_iv = SvIVX(value);
3278 } else if (value_type == HVrhek_UV) {
3279 he->refcounted_he_val.refcounted_he_u_uv = SvUVX(value);
3283 he->refcounted_he_hash = hash;
3284 he->refcounted_he_keylen = keylen;
3285 Copy(keypv, he->refcounted_he_data + key_offset, keylen, char);
3287 he->refcounted_he_hek = share_hek_flags(keypv, keylen, hash, hekflags);
3290 he->refcounted_he_data[0] = hekflags;
3291 he->refcounted_he_refcnt = 1;
3297 =for apidoc m|struct refcounted_he *|refcounted_he_new_pv|struct refcounted_he *parent|const char *key|U32 hash|SV *value|U32 flags
3299 Like L</refcounted_he_new_pvn>, but takes a nul-terminated string instead
3300 of a string/length pair.
3305 struct refcounted_he *
3306 Perl_refcounted_he_new_pv(pTHX_ struct refcounted_he *parent,
3307 const char *key, U32 hash, SV *value, U32 flags)
3309 PERL_ARGS_ASSERT_REFCOUNTED_HE_NEW_PV;
3310 return refcounted_he_new_pvn(parent, key, strlen(key), hash, value, flags);
3314 =for apidoc m|struct refcounted_he *|refcounted_he_new_sv|struct refcounted_he *parent|SV *key|U32 hash|SV *value|U32 flags
3316 Like L</refcounted_he_new_pvn>, but takes a Perl scalar instead of a
3322 struct refcounted_he *
3323 Perl_refcounted_he_new_sv(pTHX_ struct refcounted_he *parent,
3324 SV *key, U32 hash, SV *value, U32 flags)
3328 PERL_ARGS_ASSERT_REFCOUNTED_HE_NEW_SV;
3329 if (flags & REFCOUNTED_HE_KEY_UTF8)
3330 Perl_croak(aTHX_ "panic: refcounted_he_new_sv bad flags %"UVxf,
3332 keypv = SvPV_const(key, keylen);
3334 flags |= REFCOUNTED_HE_KEY_UTF8;
3335 if (!hash && SvIsCOW_shared_hash(key))
3336 hash = SvSHARED_HASH(key);
3337 return refcounted_he_new_pvn(parent, keypv, keylen, hash, value, flags);
3341 =for apidoc m|void|refcounted_he_free|struct refcounted_he *he
3343 Decrements the reference count of a C<refcounted_he> by one. If the
3344 reference count reaches zero the structure's memory is freed, which
3345 (recursively) causes a reduction of its parent C<refcounted_he>'s
3346 reference count. It is safe to pass a null pointer to this function:
3347 no action occurs in this case.
3353 Perl_refcounted_he_free(pTHX_ struct refcounted_he *he) {
3355 PERL_UNUSED_CONTEXT;
3358 struct refcounted_he *copy;
3362 new_count = --he->refcounted_he_refcnt;
3363 HINTS_REFCNT_UNLOCK;
3369 #ifndef USE_ITHREADS
3370 unshare_hek_or_pvn (he->refcounted_he_hek, 0, 0, 0);
3373 he = he->refcounted_he_next;
3374 PerlMemShared_free(copy);
3379 =for apidoc m|struct refcounted_he *|refcounted_he_inc|struct refcounted_he *he
3381 Increment the reference count of a C<refcounted_he>. The pointer to the
3382 C<refcounted_he> is also returned. It is safe to pass a null pointer
3383 to this function: no action occurs and a null pointer is returned.
3388 struct refcounted_he *
3389 Perl_refcounted_he_inc(pTHX_ struct refcounted_he *he)
3393 he->refcounted_he_refcnt++;
3394 HINTS_REFCNT_UNLOCK;
3399 /* pp_entereval is aware that labels are stored with a key ':' at the top of
3402 Perl_fetch_cop_label(pTHX_ COP *const cop, STRLEN *len, U32 *flags) {
3403 struct refcounted_he *const chain = cop->cop_hints_hash;
3405 PERL_ARGS_ASSERT_FETCH_COP_LABEL;
3410 if (chain->refcounted_he_keylen != 1)
3412 if (*REF_HE_KEY(chain) != ':')
3415 if ((STRLEN)HEK_LEN(chain->refcounted_he_hek) != 1)
3417 if (*HEK_KEY(chain->refcounted_he_hek) != ':')
3420 /* Stop anyone trying to really mess us up by adding their own value for
3422 if ((chain->refcounted_he_data[0] & HVrhek_typemask) != HVrhek_PV
3423 && (chain->refcounted_he_data[0] & HVrhek_typemask) != HVrhek_PV_UTF8)
3427 *len = chain->refcounted_he_val.refcounted_he_u_len;
3429 *flags = ((chain->refcounted_he_data[0] & HVrhek_typemask)
3430 == HVrhek_PV_UTF8) ? SVf_UTF8 : 0;
3432 return chain->refcounted_he_data + 1;
3436 Perl_store_cop_label(pTHX_ COP *const cop, const char *label, STRLEN len,
3440 PERL_ARGS_ASSERT_STORE_COP_LABEL;
3442 if (flags & ~(SVf_UTF8))
3443 Perl_croak(aTHX_ "panic: store_cop_label illegal flag bits 0x%" UVxf,
3445 labelsv = newSVpvn_flags(label, len, SVs_TEMP);
3446 if (flags & SVf_UTF8)
3449 = refcounted_he_new_pvs(cop->cop_hints_hash, ":", labelsv, 0);
3453 =for apidoc hv_assert
3455 Check that a hash is in an internally consistent state.
3463 Perl_hv_assert(pTHX_ HV *hv)
3468 int placeholders = 0;
3471 const I32 riter = HvRITER_get(hv);
3472 HE *eiter = HvEITER_get(hv);
3474 PERL_ARGS_ASSERT_HV_ASSERT;
3476 (void)hv_iterinit(hv);
3478 while ((entry = hv_iternext_flags(hv, HV_ITERNEXT_WANTPLACEHOLDERS))) {
3479 /* sanity check the values */
3480 if (HeVAL(entry) == &PL_sv_placeholder)
3484 /* sanity check the keys */
3485 if (HeSVKEY(entry)) {
3486 NOOP; /* Don't know what to check on SV keys. */
3487 } else if (HeKUTF8(entry)) {
3489 if (HeKWASUTF8(entry)) {
3490 PerlIO_printf(Perl_debug_log,
3491 "hash key has both WASUTF8 and UTF8: '%.*s'\n",
3492 (int) HeKLEN(entry), HeKEY(entry));
3495 } else if (HeKWASUTF8(entry))
3498 if (!SvTIED_mg((const SV *)hv, PERL_MAGIC_tied)) {
3499 static const char bad_count[] = "Count %d %s(s), but hash reports %d\n";
3500 const int nhashkeys = HvUSEDKEYS(hv);
3501 const int nhashplaceholders = HvPLACEHOLDERS_get(hv);
3503 if (nhashkeys != real) {
3504 PerlIO_printf(Perl_debug_log, bad_count, real, "keys", nhashkeys );
3507 if (nhashplaceholders != placeholders) {
3508 PerlIO_printf(Perl_debug_log, bad_count, placeholders, "placeholder", nhashplaceholders );
3512 if (withflags && ! HvHASKFLAGS(hv)) {
3513 PerlIO_printf(Perl_debug_log,
3514 "Hash has HASKFLAGS off but I count %d key(s) with flags\n",
3519 sv_dump(MUTABLE_SV(hv));
3521 HvRITER_set(hv, riter); /* Restore hash iterator state */
3522 HvEITER_set(hv, eiter);
3529 * c-indentation-style: bsd
3531 * indent-tabs-mode: t
3534 * ex: set ts=8 sts=4 sw=4 noet: