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) {
804 } else if(!HvREHASH(hv)) {
807 while ((counter = HeNEXT(counter)))
810 if (n_links > HV_MAX_LENGTH_BEFORE_SPLIT) {
811 /* Use only the old HvKEYS(hv) > HvMAX(hv) condition to limit
812 bucket splits on a rehashed hash, as we're not going to
813 split it again, and if someone is lucky (evil) enough to
814 get all the keys in one list they could exhaust our memory
815 as we repeatedly double the number of buckets on every
816 entry. Linear search feels a less worse thing to do. */
823 return entry ? (void *) &HeVAL(entry) : NULL;
825 return (void *) entry;
829 S_hv_magic_check(HV *hv, bool *needs_copy, bool *needs_store)
831 const MAGIC *mg = SvMAGIC(hv);
833 PERL_ARGS_ASSERT_HV_MAGIC_CHECK;
838 if (isUPPER(mg->mg_type)) {
840 if (mg->mg_type == PERL_MAGIC_tied) {
841 *needs_store = FALSE;
842 return; /* We've set all there is to set. */
845 mg = mg->mg_moremagic;
850 =for apidoc hv_scalar
852 Evaluates the hash in scalar context and returns the result. Handles magic when the hash is tied.
858 Perl_hv_scalar(pTHX_ HV *hv)
862 PERL_ARGS_ASSERT_HV_SCALAR;
864 if (SvRMAGICAL(hv)) {
865 MAGIC * const mg = mg_find((const SV *)hv, PERL_MAGIC_tied);
867 return magic_scalarpack(hv, mg);
871 if (HvTOTALKEYS((const HV *)hv))
872 Perl_sv_setpvf(aTHX_ sv, "%ld/%ld",
873 (long)HvFILL(hv), (long)HvMAX(hv) + 1);
881 =for apidoc hv_delete
883 Deletes a key/value pair in the hash. The value's SV is removed from the
884 hash, made mortal, and returned to the caller. The C<klen> is the length of
885 the key. The C<flags> value will normally be zero; if set to G_DISCARD then
886 NULL will be returned. NULL will also be returned if the key is not found.
888 =for apidoc hv_delete_ent
890 Deletes a key/value pair in the hash. The value SV is removed from the hash,
891 made mortal, and returned to the caller. The C<flags> value will normally be
892 zero; if set to G_DISCARD then NULL will be returned. NULL will also be
893 returned if the key is not found. C<hash> can be a valid precomputed hash
894 value, or 0 to ask for it to be computed.
900 S_hv_delete_common(pTHX_ HV *hv, SV *keysv, const char *key, STRLEN klen,
901 int k_flags, I32 d_flags, U32 hash)
906 register HE **oentry;
907 HE *const *first_entry;
908 bool is_utf8 = (k_flags & HVhek_UTF8) ? TRUE : FALSE;
911 if (SvRMAGICAL(hv)) {
914 hv_magic_check (hv, &needs_copy, &needs_store);
918 entry = (HE *) hv_common(hv, keysv, key, klen,
919 k_flags & ~HVhek_FREEKEY,
920 HV_FETCH_LVALUE|HV_DISABLE_UVAR_XKEY,
922 sv = entry ? HeVAL(entry) : NULL;
928 if (mg_find(sv, PERL_MAGIC_tiedelem)) {
929 /* No longer an element */
930 sv_unmagic(sv, PERL_MAGIC_tiedelem);
933 return NULL; /* element cannot be deleted */
935 #ifdef ENV_IS_CASELESS
936 else if (mg_find((const SV *)hv, PERL_MAGIC_env)) {
937 /* XXX This code isn't UTF8 clean. */
938 keysv = newSVpvn_flags(key, klen, SVs_TEMP);
939 if (k_flags & HVhek_FREEKEY) {
942 key = strupr(SvPVX(keysv));
951 xhv = (XPVHV*)SvANY(hv);
956 const char * const keysave = key;
957 key = (char*)bytes_from_utf8((U8*)key, &klen, &is_utf8);
960 k_flags |= HVhek_UTF8;
962 k_flags &= ~HVhek_UTF8;
963 if (key != keysave) {
964 if (k_flags & HVhek_FREEKEY) {
965 /* This shouldn't happen if our caller does what we expect,
966 but strictly the API allows it. */
969 k_flags |= HVhek_WASUTF8 | HVhek_FREEKEY;
971 HvHASKFLAGS_on(MUTABLE_SV(hv));
975 PERL_HASH_INTERNAL(hash, key, klen);
977 if (keysv && (SvIsCOW_shared_hash(keysv))) {
978 hash = SvSHARED_HASH(keysv);
980 PERL_HASH(hash, key, klen);
984 masked_flags = (k_flags & HVhek_MASK);
986 first_entry = oentry = &(HvARRAY(hv))[hash & (I32) HvMAX(hv)];
988 for (; entry; oentry = &HeNEXT(entry), entry = *oentry) {
990 U8 mro_changes = 0; /* 1 = isa; 2 = package moved */
994 if (HeHASH(entry) != hash) /* strings can't be equal */
996 if (HeKLEN(entry) != (I32)klen)
998 if (HeKEY(entry) != key && memNE(HeKEY(entry),key,klen)) /* is this it? */
1000 if ((HeKFLAGS(entry) ^ masked_flags) & HVhek_UTF8)
1003 if (hv == PL_strtab) {
1004 if (k_flags & HVhek_FREEKEY)
1006 Perl_croak(aTHX_ S_strtab_error, "delete");
1009 /* if placeholder is here, it's already been deleted.... */
1010 if (HeVAL(entry) == &PL_sv_placeholder) {
1011 if (k_flags & HVhek_FREEKEY)
1015 if (SvREADONLY(hv) && HeVAL(entry) && SvREADONLY(HeVAL(entry))) {
1016 hv_notallowed(k_flags, key, klen,
1017 "Attempt to delete readonly key '%"SVf"' from"
1018 " a restricted hash");
1020 if (k_flags & HVhek_FREEKEY)
1023 /* If this is a stash and the key ends with ::, then someone is
1024 * deleting a package.
1026 if (HeVAL(entry) && HvENAME_get(hv)) {
1027 gv = (GV *)HeVAL(entry);
1028 if (keysv) key = SvPV(keysv, klen);
1029 if (klen > 1 && key[klen-2] == ':' && key[klen-1] == ':'
1030 && (klen != 6 || hv!=PL_defstash || memNE(key,"main::",6))
1031 && SvTYPE(gv) == SVt_PVGV && (stash = GvHV((GV *)gv))
1032 && HvENAME_get(stash)) {
1033 /* A previous version of this code checked that the
1034 * GV was still in the symbol table by fetching the
1035 * GV with its name. That is not necessary (and
1036 * sometimes incorrect), as HvENAME cannot be set
1037 * on hv if it is not in the symtab. */
1039 /* Hang on to it for a bit. */
1040 SvREFCNT_inc_simple_void_NN(
1041 sv_2mortal((SV *)gv)
1044 else if (klen == 3 && strnEQ(key, "ISA", 3))
1048 if (d_flags & G_DISCARD)
1051 sv = sv_2mortal(HeVAL(entry));
1052 HeVAL(entry) = &PL_sv_placeholder;
1056 * If a restricted hash, rather than really deleting the entry, put
1057 * a placeholder there. This marks the key as being "approved", so
1058 * we can still access via not-really-existing key without raising
1061 if (SvREADONLY(hv)) {
1062 SvREFCNT_dec(HeVAL(entry));
1063 HeVAL(entry) = &PL_sv_placeholder;
1064 /* We'll be saving this slot, so the number of allocated keys
1065 * doesn't go down, but the number placeholders goes up */
1066 HvPLACEHOLDERS(hv)++;
1068 *oentry = HeNEXT(entry);
1069 if (SvOOK(hv) && entry == HvAUX(hv)->xhv_eiter /* HvEITER(hv) */)
1072 hv_free_ent(hv, entry);
1073 xhv->xhv_keys--; /* HvTOTALKEYS(hv)-- */
1074 if (xhv->xhv_keys == 0)
1075 HvHASKFLAGS_off(hv);
1078 if (mro_changes == 1) mro_isa_changed_in(hv);
1079 else if (mro_changes == 2)
1080 mro_package_moved(NULL, stash, gv, 1);
1084 if (SvREADONLY(hv)) {
1085 hv_notallowed(k_flags, key, klen,
1086 "Attempt to delete disallowed key '%"SVf"' from"
1087 " a restricted hash");
1090 if (k_flags & HVhek_FREEKEY)
1096 S_hsplit(pTHX_ HV *hv)
1099 register XPVHV* const xhv = (XPVHV*)SvANY(hv);
1100 const I32 oldsize = (I32) xhv->xhv_max+1; /* HvMAX(hv)+1 (sick) */
1101 register I32 newsize = oldsize * 2;
1103 char *a = (char*) HvARRAY(hv);
1105 int longest_chain = 0;
1108 PERL_ARGS_ASSERT_HSPLIT;
1110 /*PerlIO_printf(PerlIO_stderr(), "hsplit called for %p which had %d\n",
1111 (void*)hv, (int) oldsize);*/
1113 if (HvPLACEHOLDERS_get(hv) && !SvREADONLY(hv)) {
1114 /* Can make this clear any placeholders first for non-restricted hashes,
1115 even though Storable rebuilds restricted hashes by putting in all the
1116 placeholders (first) before turning on the readonly flag, because
1117 Storable always pre-splits the hash. */
1118 hv_clear_placeholders(hv);
1122 #if defined(STRANGE_MALLOC) || defined(MYMALLOC)
1123 Renew(a, PERL_HV_ARRAY_ALLOC_BYTES(newsize)
1124 + (SvOOK(hv) ? sizeof(struct xpvhv_aux) : 0), char);
1130 Move(&a[oldsize * sizeof(HE*)], &a[newsize * sizeof(HE*)], 1, struct xpvhv_aux);
1133 Newx(a, PERL_HV_ARRAY_ALLOC_BYTES(newsize)
1134 + (SvOOK(hv) ? sizeof(struct xpvhv_aux) : 0), char);
1139 Copy(HvARRAY(hv), a, oldsize * sizeof(HE*), char);
1141 Copy(HvAUX(hv), &a[newsize * sizeof(HE*)], 1, struct xpvhv_aux);
1143 Safefree(HvARRAY(hv));
1147 Zero(&a[oldsize * sizeof(HE*)], (newsize-oldsize) * sizeof(HE*), char); /* zero 2nd half*/
1148 xhv->xhv_max = --newsize; /* HvMAX(hv) = --newsize */
1149 HvARRAY(hv) = (HE**) a;
1152 for (i=0; i<oldsize; i++,aep++) {
1153 int left_length = 0;
1154 int right_length = 0;
1159 if (!entry) /* non-existent */
1163 if ((HeHASH(entry) & newsize) != (U32)i) {
1164 *oentry = HeNEXT(entry);
1165 HeNEXT(entry) = *bep;
1170 oentry = &HeNEXT(entry);
1175 /* I think we don't actually need to keep track of the longest length,
1176 merely flag if anything is too long. But for the moment while
1177 developing this code I'll track it. */
1178 if (left_length > longest_chain)
1179 longest_chain = left_length;
1180 if (right_length > longest_chain)
1181 longest_chain = right_length;
1185 /* Pick your policy for "hashing isn't working" here: */
1186 if (longest_chain <= HV_MAX_LENGTH_BEFORE_SPLIT /* split worked? */
1191 if (hv == PL_strtab) {
1192 /* Urg. Someone is doing something nasty to the string table.
1197 /* Awooga. Awooga. Pathological data. */
1198 /*PerlIO_printf(PerlIO_stderr(), "%p %d of %d with %d/%d buckets\n", (void*)hv,
1199 longest_chain, HvTOTALKEYS(hv), HvFILL(hv), 1+HvMAX(hv));*/
1202 Newxz(a, PERL_HV_ARRAY_ALLOC_BYTES(newsize)
1203 + (SvOOK(hv) ? sizeof(struct xpvhv_aux) : 0), char);
1205 Copy(HvAUX(hv), &a[newsize * sizeof(HE*)], 1, struct xpvhv_aux);
1208 was_shared = HvSHAREKEYS(hv);
1210 HvSHAREKEYS_off(hv);
1215 for (i=0; i<newsize; i++,aep++) {
1216 register HE *entry = *aep;
1218 /* We're going to trash this HE's next pointer when we chain it
1219 into the new hash below, so store where we go next. */
1220 HE * const next = HeNEXT(entry);
1225 PERL_HASH_INTERNAL(hash, HeKEY(entry), HeKLEN(entry));
1230 = save_hek_flags(HeKEY(entry), HeKLEN(entry),
1231 hash, HeKFLAGS(entry));
1232 unshare_hek (HeKEY_hek(entry));
1233 HeKEY_hek(entry) = new_hek;
1235 /* Not shared, so simply write the new hash in. */
1236 HeHASH(entry) = hash;
1238 /*PerlIO_printf(PerlIO_stderr(), "%d ", HeKFLAGS(entry));*/
1239 HEK_REHASH_on(HeKEY_hek(entry));
1240 /*PerlIO_printf(PerlIO_stderr(), "%d\n", HeKFLAGS(entry));*/
1242 /* Copy oentry to the correct new chain. */
1243 bep = ((HE**)a) + (hash & (I32) xhv->xhv_max);
1244 HeNEXT(entry) = *bep;
1250 Safefree (HvARRAY(hv));
1251 HvARRAY(hv) = (HE **)a;
1255 Perl_hv_ksplit(pTHX_ HV *hv, IV newmax)
1258 register XPVHV* xhv = (XPVHV*)SvANY(hv);
1259 const I32 oldsize = (I32) xhv->xhv_max+1; /* HvMAX(hv)+1 (sick) */
1260 register I32 newsize;
1265 PERL_ARGS_ASSERT_HV_KSPLIT;
1267 newsize = (I32) newmax; /* possible truncation here */
1268 if (newsize != newmax || newmax <= oldsize)
1270 while ((newsize & (1 + ~newsize)) != newsize) {
1271 newsize &= ~(newsize & (1 + ~newsize)); /* get proper power of 2 */
1273 if (newsize < newmax)
1275 if (newsize < newmax)
1276 return; /* overflow detection */
1278 a = (char *) HvARRAY(hv);
1281 #if defined(STRANGE_MALLOC) || defined(MYMALLOC)
1282 Renew(a, PERL_HV_ARRAY_ALLOC_BYTES(newsize)
1283 + (SvOOK(hv) ? sizeof(struct xpvhv_aux) : 0), char);
1289 Copy(&a[oldsize * sizeof(HE*)], &a[newsize * sizeof(HE*)], 1, struct xpvhv_aux);
1292 Newx(a, PERL_HV_ARRAY_ALLOC_BYTES(newsize)
1293 + (SvOOK(hv) ? sizeof(struct xpvhv_aux) : 0), char);
1298 Copy(HvARRAY(hv), a, oldsize * sizeof(HE*), char);
1300 Copy(HvAUX(hv), &a[newsize * sizeof(HE*)], 1, struct xpvhv_aux);
1302 Safefree(HvARRAY(hv));
1305 Zero(&a[oldsize * sizeof(HE*)], (newsize-oldsize) * sizeof(HE*), char); /* zero 2nd half*/
1308 Newxz(a, PERL_HV_ARRAY_ALLOC_BYTES(newsize), char);
1310 xhv->xhv_max = --newsize; /* HvMAX(hv) = --newsize */
1311 HvARRAY(hv) = (HE **) a;
1312 if (!xhv->xhv_keys /* !HvTOTALKEYS(hv) */) /* skip rest if no entries */
1316 for (i=0; i<oldsize; i++,aep++) {
1320 if (!entry) /* non-existent */
1323 register I32 j = (HeHASH(entry) & newsize);
1327 *oentry = HeNEXT(entry);
1328 HeNEXT(entry) = aep[j];
1332 oentry = &HeNEXT(entry);
1339 Perl_newHVhv(pTHX_ HV *ohv)
1342 HV * const hv = newHV();
1345 if (!ohv || !HvTOTALKEYS(ohv))
1347 hv_max = HvMAX(ohv);
1349 if (!SvMAGICAL((const SV *)ohv)) {
1350 /* It's an ordinary hash, so copy it fast. AMS 20010804 */
1352 const bool shared = !!HvSHAREKEYS(ohv);
1353 HE **ents, ** const oents = (HE **)HvARRAY(ohv);
1355 Newx(a, PERL_HV_ARRAY_ALLOC_BYTES(hv_max+1), char);
1358 /* In each bucket... */
1359 for (i = 0; i <= hv_max; i++) {
1361 HE *oent = oents[i];
1368 /* Copy the linked list of entries. */
1369 for (; oent; oent = HeNEXT(oent)) {
1370 const U32 hash = HeHASH(oent);
1371 const char * const key = HeKEY(oent);
1372 const STRLEN len = HeKLEN(oent);
1373 const int flags = HeKFLAGS(oent);
1374 HE * const ent = new_HE();
1375 SV *const val = HeVAL(oent);
1377 HeVAL(ent) = SvIMMORTAL(val) ? val : newSVsv(val);
1379 = shared ? share_hek_flags(key, len, hash, flags)
1380 : save_hek_flags(key, len, hash, flags);
1391 HvTOTALKEYS(hv) = HvTOTALKEYS(ohv);
1395 /* Iterate over ohv, copying keys and values one at a time. */
1397 const I32 riter = HvRITER_get(ohv);
1398 HE * const eiter = HvEITER_get(ohv);
1399 STRLEN hv_fill = HvFILL(ohv);
1401 /* Can we use fewer buckets? (hv_max is always 2^n-1) */
1402 while (hv_max && hv_max + 1 >= hv_fill * 2)
1403 hv_max = hv_max / 2;
1407 while ((entry = hv_iternext_flags(ohv, 0))) {
1408 SV *const val = HeVAL(entry);
1409 (void)hv_store_flags(hv, HeKEY(entry), HeKLEN(entry),
1410 SvIMMORTAL(val) ? val : newSVsv(val),
1411 HeHASH(entry), HeKFLAGS(entry));
1413 HvRITER_set(ohv, riter);
1414 HvEITER_set(ohv, eiter);
1421 =for apidoc Am|HV *|hv_copy_hints_hv|HV *ohv
1423 A specialised version of L</newHVhv> for copying C<%^H>. I<ohv> must be
1424 a pointer to a hash (which may have C<%^H> magic, but should be generally
1425 non-magical), or C<NULL> (interpreted as an empty hash). The content
1426 of I<ohv> is copied to a new hash, which has the C<%^H>-specific magic
1427 added to it. A pointer to the new hash is returned.
1433 Perl_hv_copy_hints_hv(pTHX_ HV *const ohv)
1435 HV * const hv = newHV();
1437 if (ohv && HvTOTALKEYS(ohv)) {
1438 STRLEN hv_max = HvMAX(ohv);
1439 STRLEN hv_fill = HvFILL(ohv);
1441 const I32 riter = HvRITER_get(ohv);
1442 HE * const eiter = HvEITER_get(ohv);
1444 while (hv_max && hv_max + 1 >= hv_fill * 2)
1445 hv_max = hv_max / 2;
1449 while ((entry = hv_iternext_flags(ohv, 0))) {
1450 SV *const sv = newSVsv(HeVAL(entry));
1451 SV *heksv = newSVhek(HeKEY_hek(entry));
1452 sv_magic(sv, NULL, PERL_MAGIC_hintselem,
1453 (char *)heksv, HEf_SVKEY);
1454 SvREFCNT_dec(heksv);
1455 (void)hv_store_flags(hv, HeKEY(entry), HeKLEN(entry),
1456 sv, HeHASH(entry), HeKFLAGS(entry));
1458 HvRITER_set(ohv, riter);
1459 HvEITER_set(ohv, eiter);
1461 hv_magic(hv, NULL, PERL_MAGIC_hints);
1466 Perl_hv_free_ent(pTHX_ HV *hv, register HE *entry)
1471 PERL_ARGS_ASSERT_HV_FREE_ENT;
1476 if (val && isGV(val) && isGV_with_GP(val) && GvCVu(val) && HvENAME(hv))
1477 mro_method_changed_in(hv); /* deletion of method from stash */
1479 if (HeKLEN(entry) == HEf_SVKEY) {
1480 SvREFCNT_dec(HeKEY_sv(entry));
1481 Safefree(HeKEY_hek(entry));
1483 else if (HvSHAREKEYS(hv))
1484 unshare_hek(HeKEY_hek(entry));
1486 Safefree(HeKEY_hek(entry));
1492 Perl_hv_delayfree_ent(pTHX_ HV *hv, register HE *entry)
1496 PERL_ARGS_ASSERT_HV_DELAYFREE_ENT;
1500 /* SvREFCNT_inc to counter the SvREFCNT_dec in hv_free_ent */
1501 sv_2mortal(SvREFCNT_inc(HeVAL(entry))); /* free between statements */
1502 if (HeKLEN(entry) == HEf_SVKEY) {
1503 sv_2mortal(SvREFCNT_inc(HeKEY_sv(entry)));
1505 hv_free_ent(hv, entry);
1509 =for apidoc hv_clear
1511 Clears a hash, making it empty.
1517 Perl_hv_clear(pTHX_ HV *hv)
1520 register XPVHV* xhv;
1524 DEBUG_A(Perl_hv_assert(aTHX_ hv));
1526 xhv = (XPVHV*)SvANY(hv);
1528 if (SvREADONLY(hv) && HvARRAY(hv) != NULL) {
1529 /* restricted hash: convert all keys to placeholders */
1531 for (i = 0; i <= xhv->xhv_max; i++) {
1532 HE *entry = (HvARRAY(hv))[i];
1533 for (; entry; entry = HeNEXT(entry)) {
1534 /* not already placeholder */
1535 if (HeVAL(entry) != &PL_sv_placeholder) {
1536 if (HeVAL(entry) && SvREADONLY(HeVAL(entry))) {
1537 SV* const keysv = hv_iterkeysv(entry);
1539 "Attempt to delete readonly key '%"SVf"' from a restricted hash",
1542 SvREFCNT_dec(HeVAL(entry));
1543 HeVAL(entry) = &PL_sv_placeholder;
1544 HvPLACEHOLDERS(hv)++;
1552 HvPLACEHOLDERS_set(hv, 0);
1554 Zero(HvARRAY(hv), xhv->xhv_max+1 /* HvMAX(hv)+1 */, HE*);
1557 mg_clear(MUTABLE_SV(hv));
1559 HvHASKFLAGS_off(hv);
1564 mro_isa_changed_in(hv);
1565 HvEITER_set(hv, NULL);
1570 =for apidoc hv_clear_placeholders
1572 Clears any placeholders from a hash. If a restricted hash has any of its keys
1573 marked as readonly and the key is subsequently deleted, the key is not actually
1574 deleted but is marked by assigning it a value of &PL_sv_placeholder. This tags
1575 it so it will be ignored by future operations such as iterating over the hash,
1576 but will still allow the hash to have a value reassigned to the key at some
1577 future point. This function clears any such placeholder keys from the hash.
1578 See Hash::Util::lock_keys() for an example of its use.
1584 Perl_hv_clear_placeholders(pTHX_ HV *hv)
1587 const U32 items = (U32)HvPLACEHOLDERS_get(hv);
1589 PERL_ARGS_ASSERT_HV_CLEAR_PLACEHOLDERS;
1592 clear_placeholders(hv, items);
1596 S_clear_placeholders(pTHX_ HV *hv, U32 items)
1601 PERL_ARGS_ASSERT_CLEAR_PLACEHOLDERS;
1608 /* Loop down the linked list heads */
1610 HE **oentry = &(HvARRAY(hv))[i];
1613 while ((entry = *oentry)) {
1614 if (HeVAL(entry) == &PL_sv_placeholder) {
1615 *oentry = HeNEXT(entry);
1616 if (entry == HvEITER_get(hv))
1619 hv_free_ent(hv, entry);
1623 HvTOTALKEYS(hv) -= (IV)HvPLACEHOLDERS_get(hv);
1624 if (HvKEYS(hv) == 0)
1625 HvHASKFLAGS_off(hv);
1626 HvPLACEHOLDERS_set(hv, 0);
1630 oentry = &HeNEXT(entry);
1635 /* You can't get here, hence assertion should always fail. */
1636 assert (items == 0);
1641 S_hfreeentries(pTHX_ HV *hv)
1643 /* This is the array that we're going to restore */
1644 HE **const orig_array = HvARRAY(hv);
1645 HE **tmp_array = NULL;
1646 const bool has_aux = (SvOOK(hv) == SVf_OOK);
1647 struct xpvhv_aux * current_aux = NULL;
1650 const bool mpm = PL_phase != PERL_PHASE_DESTRUCT && HvENAME(hv);
1652 PERL_ARGS_ASSERT_HFREEENTRIES;
1657 /* orig_array remains unchanged throughout the loop. If after freeing all
1658 the entries it turns out that one of the little blighters has triggered
1659 an action that has caused HvARRAY to be re-allocated, then we set
1660 array to the new HvARRAY, and try again. */
1663 /* This is the one we're going to try to empty. First time round
1664 it's the original array. (Hopefully there will only be 1 time
1666 HE ** const array = HvARRAY(hv);
1669 struct xpvhv_aux *iter = SvOOK(hv) ? HvAUX(hv) : NULL;
1671 /* If there are no keys, we only need to free items in the aux
1672 structure and then exit the loop. */
1673 const bool empty = !((XPVHV*) SvANY(hv))->xhv_keys;
1675 /* make everyone else think the array is empty, so that the destructors
1676 * called for freed entries can't recursively mess with us */
1677 if (!empty) HvARRAY(hv) = NULL;
1683 SvFLAGS(hv) &= ~SVf_OOK; /* Goodbye, aux structure. */
1684 /* What aux structure? */
1685 /* (But we still have a pointer to it in iter.) */
1687 /* Copy the name and MRO stuff to a new aux structure
1689 if (iter->xhv_name_u.xhvnameu_name || iter->xhv_mro_meta) {
1690 struct xpvhv_aux * const newaux = hv_auxinit(hv);
1691 newaux->xhv_name_count = iter->xhv_name_count;
1692 if (newaux->xhv_name_count)
1693 newaux->xhv_name_u.xhvnameu_names
1694 = iter->xhv_name_u.xhvnameu_names;
1696 newaux->xhv_name_u.xhvnameu_name
1697 = iter->xhv_name_u.xhvnameu_name;
1699 iter->xhv_name_u.xhvnameu_name = NULL;
1700 newaux->xhv_mro_meta = iter->xhv_mro_meta;
1701 iter->xhv_mro_meta = NULL;
1704 /* Because we have taken xhv_name and xhv_mro_meta out, the
1705 only allocated pointers in the aux structure that might
1706 exist are the back-reference array and xhv_eiter.
1710 /* weak references: if called from sv_clear(), the backrefs
1711 * should already have been killed; if there are any left, its
1712 * because we're doing hv_clear() or hv_undef(), and the HV
1713 * will continue to live.
1714 * Because while freeing the entries we fake up a NULL HvARRAY
1715 * (and hence HvAUX), we need to store the backref array
1716 * somewhere else; but it still needs to be visible in case
1717 * any the things we free happen to call sv_del_backref().
1718 * We do this by storing it in magic instead.
1719 * If, during the entry freeing, a destructor happens to add
1720 * a new weak backref, then sv_add_backref will look in both
1721 * places (magic in HvAUX) for the AV, but will create a new
1722 * AV in HvAUX if it can't find one (if it finds it in magic,
1723 * it moves it back into HvAUX. So at the end of the iteration
1724 * we have to allow for this. */
1727 if (iter->xhv_backreferences) {
1728 if (SvTYPE(iter->xhv_backreferences) == SVt_PVAV) {
1729 /* The sv_magic will increase the reference count of the AV,
1730 so we need to drop it first. */
1731 SvREFCNT_dec(iter->xhv_backreferences);
1732 if (AvFILLp(iter->xhv_backreferences) == -1) {
1733 /* Turns out that the array is empty. Just free it. */
1734 SvREFCNT_dec(iter->xhv_backreferences);
1737 sv_magic(MUTABLE_SV(hv),
1738 MUTABLE_SV(iter->xhv_backreferences),
1739 PERL_MAGIC_backref, NULL, 0);
1744 sv_magic(MUTABLE_SV(hv), NULL, PERL_MAGIC_backref, NULL, 0);
1745 mg = mg_find(MUTABLE_SV(hv), PERL_MAGIC_backref);
1746 mg->mg_obj = (SV*)iter->xhv_backreferences;
1748 iter->xhv_backreferences = NULL;
1751 entry = iter->xhv_eiter; /* HvEITER(hv) */
1752 if (entry && HvLAZYDEL(hv)) { /* was deleted earlier? */
1754 hv_free_ent(hv, entry);
1756 iter->xhv_riter = -1; /* HvRITER(hv) = -1 */
1757 iter->xhv_eiter = NULL; /* HvEITER(hv) = NULL */
1759 /* There are now no allocated pointers in the aux structure
1760 unless the hash is empty. */
1763 /* If there are no keys, there is nothing left to free. */
1766 /* Since we have removed the HvARRAY (and possibly replaced it by
1767 calling hv_auxinit), set the number of keys accordingly. */
1768 ((XPVHV*) SvANY(hv))->xhv_keys = 0;
1771 /* Loop down the linked list heads */
1772 HE *entry = array[i];
1775 register HE * const oentry = entry;
1776 entry = HeNEXT(entry);
1778 mpm && HeVAL(oentry) && isGV(HeVAL(oentry)) &&
1779 GvHV(HeVAL(oentry)) && HvENAME(GvHV(HeVAL(oentry)))
1782 const char * const key = HePV(oentry,klen);
1783 if (klen > 1 && key[klen-1]==':' && key[klen-2]==':') {
1785 NULL, GvHV(HeVAL(oentry)),
1786 (GV *)HeVAL(oentry), 0
1790 hv_free_ent(hv, oentry);
1794 /* As there are no allocated pointers in the aux structure, it's now
1795 safe to free the array we just cleaned up, if it's not the one we're
1796 going to put back. */
1797 if (array != orig_array) {
1802 /* Good. No-one added anything this time round. */
1806 if (--attempts == 0) {
1807 Perl_die(aTHX_ "panic: hfreeentries failed to free hash - something is repeatedly re-creating entries");
1811 /* If the array was not replaced, the rest does not apply. */
1812 if (HvARRAY(hv) == orig_array) return;
1814 /* Set aside the current array for now, in case we still need it. */
1815 if (SvOOK(hv)) current_aux = HvAUX(hv);
1817 tmp_array = HvARRAY(hv);
1819 HvARRAY(hv) = orig_array;
1821 if (has_aux && current_aux)
1822 SvFLAGS(hv) |= SVf_OOK;
1824 SvFLAGS(hv) &=~SVf_OOK;
1826 /* If the hash was actually a symbol table, put the name and MRO
1829 struct xpvhv_aux * const aux
1830 = SvOOK(hv) ? HvAUX(hv) : hv_auxinit(hv);
1831 aux->xhv_name_count = current_aux->xhv_name_count;
1832 if(aux->xhv_name_count)
1833 aux->xhv_name_u.xhvnameu_names
1834 = current_aux->xhv_name_u.xhvnameu_names;
1836 aux->xhv_name_u.xhvnameu_name
1837 = current_aux->xhv_name_u.xhvnameu_name;
1838 aux->xhv_mro_meta = current_aux->xhv_mro_meta;
1841 if (tmp_array) Safefree(tmp_array);
1845 =for apidoc hv_undef
1853 Perl_hv_undef_flags(pTHX_ HV *hv, U32 flags)
1856 register XPVHV* xhv;
1861 DEBUG_A(Perl_hv_assert(aTHX_ hv));
1862 xhv = (XPVHV*)SvANY(hv);
1864 /* The name must be deleted before the call to hfreeeeentries so that
1865 CVs are anonymised properly. But the effective name must be pre-
1866 served until after that call (and only deleted afterwards if the
1867 call originated from sv_clear). For stashes with one name that is
1868 both the canonical name and the effective name, hv_name_set has to
1869 allocate an array for storing the effective name. We can skip that
1870 during global destruction, as it does not matter where the CVs point
1871 if they will be freed anyway. */
1872 if (PL_phase != PERL_PHASE_DESTRUCT && (name = HvNAME(hv))) {
1874 (void)hv_delete(PL_stashcache, name, HvNAMELEN_get(hv), G_DISCARD);
1875 hv_name_set(hv, NULL, 0, 0);
1879 struct xpvhv_aux * const aux = HvAUX(hv);
1880 struct mro_meta *meta;
1881 bool zeroed = FALSE;
1883 if ((name = HvENAME_get(hv))) {
1884 if (PL_phase != PERL_PHASE_DESTRUCT) {
1885 /* This must come at this point in case
1886 mro_isa_changed_in dies. */
1887 Zero(HvARRAY(hv), xhv->xhv_max+1 /* HvMAX(hv)+1 */, HE*);
1890 mro_isa_changed_in(hv);
1894 PL_stashcache, name, HvENAMELEN_get(hv), G_DISCARD
1898 /* If this call originated from sv_clear, then we must check for
1899 * effective names that need freeing, as well as the usual name. */
1901 if (flags & HV_NAME_SETALL ? !!aux->xhv_name_u.xhvnameu_name : !!name) {
1902 if (name && PL_stashcache)
1903 (void)hv_delete(PL_stashcache, name, HvNAMELEN_get(hv), G_DISCARD);
1904 hv_name_set(hv, NULL, 0, flags);
1906 if((meta = aux->xhv_mro_meta)) {
1907 if (meta->mro_linear_all) {
1908 SvREFCNT_dec(MUTABLE_SV(meta->mro_linear_all));
1909 meta->mro_linear_all = NULL;
1910 /* This is just acting as a shortcut pointer. */
1911 meta->mro_linear_current = NULL;
1912 } else if (meta->mro_linear_current) {
1913 /* Only the current MRO is stored, so this owns the data.
1915 SvREFCNT_dec(meta->mro_linear_current);
1916 meta->mro_linear_current = NULL;
1918 if(meta->mro_nextmethod) SvREFCNT_dec(meta->mro_nextmethod);
1919 SvREFCNT_dec(meta->isa);
1921 aux->xhv_mro_meta = NULL;
1923 if (!aux->xhv_name_u.xhvnameu_name)
1924 SvFLAGS(hv) &= ~SVf_OOK;
1926 Zero(HvARRAY(hv), xhv->xhv_max+1 /* HvMAX(hv)+1 */, HE*);
1929 Safefree(HvARRAY(hv));
1930 xhv->xhv_max = 7; /* HvMAX(hv) = 7 (it's a normal hash) */
1933 HvPLACEHOLDERS_set(hv, 0);
1936 mg_clear(MUTABLE_SV(hv));
1942 Returns the number of hash buckets that happen to be in use. This function is
1943 wrapped by the macro C<HvFILL>.
1945 Previously this value was stored in the HV structure, rather than being
1946 calculated on demand.
1952 Perl_hv_fill(pTHX_ HV const *const hv)
1955 HE **ents = HvARRAY(hv);
1957 PERL_ARGS_ASSERT_HV_FILL;
1960 HE *const *const last = ents + HvMAX(hv);
1961 count = last + 1 - ents;
1966 } while (++ents <= last);
1971 static struct xpvhv_aux*
1972 S_hv_auxinit(HV *hv) {
1973 struct xpvhv_aux *iter;
1976 PERL_ARGS_ASSERT_HV_AUXINIT;
1979 Newxz(array, PERL_HV_ARRAY_ALLOC_BYTES(HvMAX(hv) + 1)
1980 + sizeof(struct xpvhv_aux), char);
1982 array = (char *) HvARRAY(hv);
1983 Renew(array, PERL_HV_ARRAY_ALLOC_BYTES(HvMAX(hv) + 1)
1984 + sizeof(struct xpvhv_aux), char);
1986 HvARRAY(hv) = (HE**) array;
1987 /* SvOOK_on(hv) attacks the IV flags. */
1988 SvFLAGS(hv) |= SVf_OOK;
1991 iter->xhv_riter = -1; /* HvRITER(hv) = -1 */
1992 iter->xhv_eiter = NULL; /* HvEITER(hv) = NULL */
1993 iter->xhv_name_u.xhvnameu_name = 0;
1994 iter->xhv_name_count = 0;
1995 iter->xhv_backreferences = 0;
1996 iter->xhv_mro_meta = NULL;
2001 =for apidoc hv_iterinit
2003 Prepares a starting point to traverse a hash table. Returns the number of
2004 keys in the hash (i.e. the same as C<HvKEYS(hv)>). The return value is
2005 currently only meaningful for hashes without tie magic.
2007 NOTE: Before version 5.004_65, C<hv_iterinit> used to return the number of
2008 hash buckets that happen to be in use. If you still need that esoteric
2009 value, you can get it through the macro C<HvFILL(hv)>.
2016 Perl_hv_iterinit(pTHX_ HV *hv)
2018 PERL_ARGS_ASSERT_HV_ITERINIT;
2020 /* FIXME: Are we not NULL, or do we croak? Place bets now! */
2023 Perl_croak(aTHX_ "Bad hash");
2026 struct xpvhv_aux * const iter = HvAUX(hv);
2027 HE * const entry = iter->xhv_eiter; /* HvEITER(hv) */
2028 if (entry && HvLAZYDEL(hv)) { /* was deleted earlier? */
2030 hv_free_ent(hv, entry);
2032 iter->xhv_riter = -1; /* HvRITER(hv) = -1 */
2033 iter->xhv_eiter = NULL; /* HvEITER(hv) = NULL */
2038 /* used to be xhv->xhv_fill before 5.004_65 */
2039 return HvTOTALKEYS(hv);
2043 Perl_hv_riter_p(pTHX_ HV *hv) {
2044 struct xpvhv_aux *iter;
2046 PERL_ARGS_ASSERT_HV_RITER_P;
2049 Perl_croak(aTHX_ "Bad hash");
2051 iter = SvOOK(hv) ? HvAUX(hv) : hv_auxinit(hv);
2052 return &(iter->xhv_riter);
2056 Perl_hv_eiter_p(pTHX_ HV *hv) {
2057 struct xpvhv_aux *iter;
2059 PERL_ARGS_ASSERT_HV_EITER_P;
2062 Perl_croak(aTHX_ "Bad hash");
2064 iter = SvOOK(hv) ? HvAUX(hv) : hv_auxinit(hv);
2065 return &(iter->xhv_eiter);
2069 Perl_hv_riter_set(pTHX_ HV *hv, I32 riter) {
2070 struct xpvhv_aux *iter;
2072 PERL_ARGS_ASSERT_HV_RITER_SET;
2075 Perl_croak(aTHX_ "Bad hash");
2083 iter = hv_auxinit(hv);
2085 iter->xhv_riter = riter;
2089 Perl_hv_eiter_set(pTHX_ HV *hv, HE *eiter) {
2090 struct xpvhv_aux *iter;
2092 PERL_ARGS_ASSERT_HV_EITER_SET;
2095 Perl_croak(aTHX_ "Bad hash");
2100 /* 0 is the default so don't go malloc()ing a new structure just to
2105 iter = hv_auxinit(hv);
2107 iter->xhv_eiter = eiter;
2111 Perl_hv_name_set(pTHX_ HV *hv, const char *name, U32 len, U32 flags)
2114 struct xpvhv_aux *iter;
2118 PERL_ARGS_ASSERT_HV_NAME_SET;
2119 PERL_UNUSED_ARG(flags);
2122 Perl_croak(aTHX_ "panic: hv name too long (%"UVuf")", (UV) len);
2126 if (iter->xhv_name_u.xhvnameu_name) {
2127 if(iter->xhv_name_count) {
2128 if(flags & HV_NAME_SETALL) {
2129 HEK ** const name = HvAUX(hv)->xhv_name_u.xhvnameu_names;
2130 HEK **hekp = name + (
2131 iter->xhv_name_count < 0
2132 ? -iter->xhv_name_count
2133 : iter->xhv_name_count
2135 while(hekp-- > name+1)
2136 unshare_hek_or_pvn(*hekp, 0, 0, 0);
2137 /* The first elem may be null. */
2138 if(*name) unshare_hek_or_pvn(*name, 0, 0, 0);
2140 spot = &iter->xhv_name_u.xhvnameu_name;
2141 iter->xhv_name_count = 0;
2144 if(iter->xhv_name_count > 0) {
2145 /* shift some things over */
2147 iter->xhv_name_u.xhvnameu_names, iter->xhv_name_count + 1, HEK *
2149 spot = iter->xhv_name_u.xhvnameu_names;
2150 spot[iter->xhv_name_count] = spot[1];
2152 iter->xhv_name_count = -(iter->xhv_name_count + 1);
2154 else if(*(spot = iter->xhv_name_u.xhvnameu_names)) {
2155 unshare_hek_or_pvn(*spot, 0, 0, 0);
2159 else if (flags & HV_NAME_SETALL) {
2160 unshare_hek_or_pvn(iter->xhv_name_u.xhvnameu_name, 0, 0, 0);
2161 spot = &iter->xhv_name_u.xhvnameu_name;
2164 HEK * const existing_name = iter->xhv_name_u.xhvnameu_name;
2165 Newx(iter->xhv_name_u.xhvnameu_names, 2, HEK *);
2166 iter->xhv_name_count = -2;
2167 spot = iter->xhv_name_u.xhvnameu_names;
2168 spot[1] = existing_name;
2171 else { spot = &iter->xhv_name_u.xhvnameu_name; iter->xhv_name_count = 0; }
2176 iter = hv_auxinit(hv);
2177 spot = &iter->xhv_name_u.xhvnameu_name;
2179 PERL_HASH(hash, name, len);
2180 *spot = name ? share_hek(name, len, hash) : NULL;
2184 =for apidoc hv_ename_add
2186 Adds a name to a stash's internal list of effective names. See
2189 This is called when a stash is assigned to a new location in the symbol
2196 Perl_hv_ename_add(pTHX_ HV *hv, const char *name, U32 len, U32 flags)
2199 struct xpvhv_aux *aux = SvOOK(hv) ? HvAUX(hv) : hv_auxinit(hv);
2202 PERL_ARGS_ASSERT_HV_ENAME_ADD;
2203 PERL_UNUSED_ARG(flags);
2206 Perl_croak(aTHX_ "panic: hv name too long (%"UVuf")", (UV) len);
2208 PERL_HASH(hash, name, len);
2210 if (aux->xhv_name_count) {
2211 HEK ** const xhv_name = aux->xhv_name_u.xhvnameu_names;
2212 I32 count = aux->xhv_name_count;
2213 HEK **hekp = xhv_name + (count < 0 ? -count : count);
2214 while (hekp-- > xhv_name)
2216 HEK_LEN(*hekp) == (I32)len && memEQ(HEK_KEY(*hekp), name, len)
2218 if (hekp == xhv_name && count < 0)
2219 aux->xhv_name_count = -count;
2222 if (count < 0) aux->xhv_name_count--, count = -count;
2223 else aux->xhv_name_count++;
2224 Renew(aux->xhv_name_u.xhvnameu_names, count + 1, HEK *);
2225 (aux->xhv_name_u.xhvnameu_names)[count] = share_hek(name, len, hash);
2228 HEK *existing_name = aux->xhv_name_u.xhvnameu_name;
2230 existing_name && HEK_LEN(existing_name) == (I32)len
2231 && memEQ(HEK_KEY(existing_name), name, len)
2233 Newx(aux->xhv_name_u.xhvnameu_names, 2, HEK *);
2234 aux->xhv_name_count = existing_name ? 2 : -2;
2235 *aux->xhv_name_u.xhvnameu_names = existing_name;
2236 (aux->xhv_name_u.xhvnameu_names)[1] = share_hek(name, len, hash);
2241 =for apidoc hv_ename_delete
2243 Removes a name from a stash's internal list of effective names. If this is
2244 the name returned by C<HvENAME>, then another name in the list will take
2245 its place (C<HvENAME> will use it).
2247 This is called when a stash is deleted from the symbol table.
2253 Perl_hv_ename_delete(pTHX_ HV *hv, const char *name, U32 len, U32 flags)
2256 struct xpvhv_aux *aux;
2258 PERL_ARGS_ASSERT_HV_ENAME_DELETE;
2259 PERL_UNUSED_ARG(flags);
2262 Perl_croak(aTHX_ "panic: hv name too long (%"UVuf")", (UV) len);
2264 if (!SvOOK(hv)) return;
2267 if (!aux->xhv_name_u.xhvnameu_name) return;
2269 if (aux->xhv_name_count) {
2270 HEK ** const namep = aux->xhv_name_u.xhvnameu_names;
2271 I32 const count = aux->xhv_name_count;
2272 HEK **victim = namep + (count < 0 ? -count : count);
2273 while (victim-- > namep + 1)
2275 HEK_LEN(*victim) == (I32)len
2276 && memEQ(HEK_KEY(*victim), name, len)
2278 unshare_hek_or_pvn(*victim, 0, 0, 0);
2279 if (count < 0) ++aux->xhv_name_count;
2280 else --aux->xhv_name_count;
2282 (aux->xhv_name_count == 1 || aux->xhv_name_count == -1)
2284 ) { /* if there are none left */
2286 aux->xhv_name_u.xhvnameu_names = NULL;
2287 aux->xhv_name_count = 0;
2290 /* Move the last one back to fill the empty slot. It
2291 does not matter what order they are in. */
2292 *victim = *(namep + (count < 0 ? -count : count) - 1);
2297 count > 0 && HEK_LEN(*namep) == (I32)len
2298 && memEQ(HEK_KEY(*namep),name,len)
2300 aux->xhv_name_count = -count;
2304 HEK_LEN(aux->xhv_name_u.xhvnameu_name) == (I32)len
2305 && memEQ(HEK_KEY(aux->xhv_name_u.xhvnameu_name), name, len)
2307 HEK * const namehek = aux->xhv_name_u.xhvnameu_name;
2308 Newx(aux->xhv_name_u.xhvnameu_names, 1, HEK *);
2309 *aux->xhv_name_u.xhvnameu_names = namehek;
2310 aux->xhv_name_count = -1;
2315 Perl_hv_backreferences_p(pTHX_ HV *hv) {
2316 struct xpvhv_aux * const iter = SvOOK(hv) ? HvAUX(hv) : hv_auxinit(hv);
2318 PERL_ARGS_ASSERT_HV_BACKREFERENCES_P;
2319 PERL_UNUSED_CONTEXT;
2321 return &(iter->xhv_backreferences);
2325 Perl_hv_kill_backrefs(pTHX_ HV *hv) {
2328 PERL_ARGS_ASSERT_HV_KILL_BACKREFS;
2333 av = HvAUX(hv)->xhv_backreferences;
2336 HvAUX(hv)->xhv_backreferences = 0;
2337 Perl_sv_kill_backrefs(aTHX_ MUTABLE_SV(hv), av);
2338 if (SvTYPE(av) == SVt_PVAV)
2344 hv_iternext is implemented as a macro in hv.h
2346 =for apidoc hv_iternext
2348 Returns entries from a hash iterator. See C<hv_iterinit>.
2350 You may call C<hv_delete> or C<hv_delete_ent> on the hash entry that the
2351 iterator currently points to, without losing your place or invalidating your
2352 iterator. Note that in this case the current entry is deleted from the hash
2353 with your iterator holding the last reference to it. Your iterator is flagged
2354 to free the entry on the next call to C<hv_iternext>, so you must not discard
2355 your iterator immediately else the entry will leak - call C<hv_iternext> to
2356 trigger the resource deallocation.
2358 =for apidoc hv_iternext_flags
2360 Returns entries from a hash iterator. See C<hv_iterinit> and C<hv_iternext>.
2361 The C<flags> value will normally be zero; if HV_ITERNEXT_WANTPLACEHOLDERS is
2362 set the placeholders keys (for restricted hashes) will be returned in addition
2363 to normal keys. By default placeholders are automatically skipped over.
2364 Currently a placeholder is implemented with a value that is
2365 C<&Perl_sv_placeholder>. Note that the implementation of placeholders and
2366 restricted hashes may change, and the implementation currently is
2367 insufficiently abstracted for any change to be tidy.
2373 Perl_hv_iternext_flags(pTHX_ HV *hv, I32 flags)
2376 register XPVHV* xhv;
2380 struct xpvhv_aux *iter;
2382 PERL_ARGS_ASSERT_HV_ITERNEXT_FLAGS;
2385 Perl_croak(aTHX_ "Bad hash");
2387 xhv = (XPVHV*)SvANY(hv);
2390 /* Too many things (well, pp_each at least) merrily assume that you can
2391 call iv_iternext without calling hv_iterinit, so we'll have to deal
2397 oldentry = entry = iter->xhv_eiter; /* HvEITER(hv) */
2398 if (SvMAGICAL(hv) && SvRMAGICAL(hv)) {
2399 if ( ( mg = mg_find((const SV *)hv, PERL_MAGIC_tied) ) ) {
2400 SV * const key = sv_newmortal();
2402 sv_setsv(key, HeSVKEY_force(entry));
2403 SvREFCNT_dec(HeSVKEY(entry)); /* get rid of previous key */
2409 /* one HE per MAGICAL hash */
2410 iter->xhv_eiter = entry = new_HE(); /* HvEITER(hv) = new_HE() */
2412 Newxz(k, HEK_BASESIZE + sizeof(const SV *), char);
2414 HeKEY_hek(entry) = hek;
2415 HeKLEN(entry) = HEf_SVKEY;
2417 magic_nextpack(MUTABLE_SV(hv),mg,key);
2419 /* force key to stay around until next time */
2420 HeSVKEY_set(entry, SvREFCNT_inc_simple_NN(key));
2421 return entry; /* beware, hent_val is not set */
2423 SvREFCNT_dec(HeVAL(entry));
2424 Safefree(HeKEY_hek(entry));
2426 iter->xhv_eiter = NULL; /* HvEITER(hv) = NULL */
2430 #if defined(DYNAMIC_ENV_FETCH) && !defined(__riscos__) /* set up %ENV for iteration */
2431 if (!entry && SvRMAGICAL((const SV *)hv)
2432 && mg_find((const SV *)hv, PERL_MAGIC_env)) {
2435 /* The prime_env_iter() on VMS just loaded up new hash values
2436 * so the iteration count needs to be reset back to the beginning
2440 oldentry = entry = iter->xhv_eiter; /* HvEITER(hv) */
2445 /* hv_iterint now ensures this. */
2446 assert (HvARRAY(hv));
2448 /* At start of hash, entry is NULL. */
2451 entry = HeNEXT(entry);
2452 if (!(flags & HV_ITERNEXT_WANTPLACEHOLDERS)) {
2454 * Skip past any placeholders -- don't want to include them in
2457 while (entry && HeVAL(entry) == &PL_sv_placeholder) {
2458 entry = HeNEXT(entry);
2463 /* Skip the entire loop if the hash is empty. */
2464 if ((flags & HV_ITERNEXT_WANTPLACEHOLDERS)
2465 ? HvTOTALKEYS(hv) : HvUSEDKEYS(hv)) {
2467 /* OK. Come to the end of the current list. Grab the next one. */
2469 iter->xhv_riter++; /* HvRITER(hv)++ */
2470 if (iter->xhv_riter > (I32)xhv->xhv_max /* HvRITER(hv) > HvMAX(hv) */) {
2471 /* There is no next one. End of the hash. */
2472 iter->xhv_riter = -1; /* HvRITER(hv) = -1 */
2475 entry = (HvARRAY(hv))[iter->xhv_riter];
2477 if (!(flags & HV_ITERNEXT_WANTPLACEHOLDERS)) {
2478 /* If we have an entry, but it's a placeholder, don't count it.
2480 while (entry && HeVAL(entry) == &PL_sv_placeholder)
2481 entry = HeNEXT(entry);
2483 /* Will loop again if this linked list starts NULL
2484 (for HV_ITERNEXT_WANTPLACEHOLDERS)
2485 or if we run through it and find only placeholders. */
2489 if (oldentry && HvLAZYDEL(hv)) { /* was deleted earlier? */
2491 hv_free_ent(hv, oldentry);
2494 /*if (HvREHASH(hv) && entry && !HeKREHASH(entry))
2495 PerlIO_printf(PerlIO_stderr(), "Awooga %p %p\n", (void*)hv, (void*)entry);*/
2497 iter->xhv_eiter = entry; /* HvEITER(hv) = entry */
2502 =for apidoc hv_iterkey
2504 Returns the key from the current position of the hash iterator. See
2511 Perl_hv_iterkey(pTHX_ register HE *entry, I32 *retlen)
2513 PERL_ARGS_ASSERT_HV_ITERKEY;
2515 if (HeKLEN(entry) == HEf_SVKEY) {
2517 char * const p = SvPV(HeKEY_sv(entry), len);
2522 *retlen = HeKLEN(entry);
2523 return HeKEY(entry);
2527 /* unlike hv_iterval(), this always returns a mortal copy of the key */
2529 =for apidoc hv_iterkeysv
2531 Returns the key as an C<SV*> from the current position of the hash
2532 iterator. The return value will always be a mortal copy of the key. Also
2539 Perl_hv_iterkeysv(pTHX_ register HE *entry)
2541 PERL_ARGS_ASSERT_HV_ITERKEYSV;
2543 return sv_2mortal(newSVhek(HeKEY_hek(entry)));
2547 =for apidoc hv_iterval
2549 Returns the value from the current position of the hash iterator. See
2556 Perl_hv_iterval(pTHX_ HV *hv, register HE *entry)
2558 PERL_ARGS_ASSERT_HV_ITERVAL;
2560 if (SvRMAGICAL(hv)) {
2561 if (mg_find((const SV *)hv, PERL_MAGIC_tied)) {
2562 SV* const sv = sv_newmortal();
2563 if (HeKLEN(entry) == HEf_SVKEY)
2564 mg_copy(MUTABLE_SV(hv), sv, (char*)HeKEY_sv(entry), HEf_SVKEY);
2566 mg_copy(MUTABLE_SV(hv), sv, HeKEY(entry), HeKLEN(entry));
2570 return HeVAL(entry);
2574 =for apidoc hv_iternextsv
2576 Performs an C<hv_iternext>, C<hv_iterkey>, and C<hv_iterval> in one
2583 Perl_hv_iternextsv(pTHX_ HV *hv, char **key, I32 *retlen)
2585 HE * const he = hv_iternext_flags(hv, 0);
2587 PERL_ARGS_ASSERT_HV_ITERNEXTSV;
2591 *key = hv_iterkey(he, retlen);
2592 return hv_iterval(hv, he);
2599 =for apidoc hv_magic
2601 Adds magic to a hash. See C<sv_magic>.
2606 /* possibly free a shared string if no one has access to it
2607 * len and hash must both be valid for str.
2610 Perl_unsharepvn(pTHX_ const char *str, I32 len, U32 hash)
2612 unshare_hek_or_pvn (NULL, str, len, hash);
2617 Perl_unshare_hek(pTHX_ HEK *hek)
2620 unshare_hek_or_pvn(hek, NULL, 0, 0);
2623 /* possibly free a shared string if no one has access to it
2624 hek if non-NULL takes priority over the other 3, else str, len and hash
2625 are used. If so, len and hash must both be valid for str.
2628 S_unshare_hek_or_pvn(pTHX_ const HEK *hek, const char *str, I32 len, U32 hash)
2631 register XPVHV* xhv;
2633 register HE **oentry;
2635 bool is_utf8 = FALSE;
2637 const char * const save = str;
2638 struct shared_he *he = NULL;
2641 /* Find the shared he which is just before us in memory. */
2642 he = (struct shared_he *)(((char *)hek)
2643 - STRUCT_OFFSET(struct shared_he,
2646 /* Assert that the caller passed us a genuine (or at least consistent)
2648 assert (he->shared_he_he.hent_hek == hek);
2650 if (he->shared_he_he.he_valu.hent_refcount - 1) {
2651 --he->shared_he_he.he_valu.hent_refcount;
2655 hash = HEK_HASH(hek);
2656 } else if (len < 0) {
2657 STRLEN tmplen = -len;
2659 /* See the note in hv_fetch(). --jhi */
2660 str = (char*)bytes_from_utf8((U8*)str, &tmplen, &is_utf8);
2663 k_flags = HVhek_UTF8;
2665 k_flags |= HVhek_WASUTF8 | HVhek_FREEKEY;
2668 /* what follows was the moral equivalent of:
2669 if ((Svp = hv_fetch(PL_strtab, tmpsv, FALSE, hash))) {
2671 hv_delete(PL_strtab, str, len, G_DISCARD, hash);
2673 xhv = (XPVHV*)SvANY(PL_strtab);
2674 /* assert(xhv_array != 0) */
2675 first = oentry = &(HvARRAY(PL_strtab))[hash & (I32) HvMAX(PL_strtab)];
2677 const HE *const he_he = &(he->shared_he_he);
2678 for (entry = *oentry; entry; oentry = &HeNEXT(entry), entry = *oentry) {
2683 const int flags_masked = k_flags & HVhek_MASK;
2684 for (entry = *oentry; entry; oentry = &HeNEXT(entry), entry = *oentry) {
2685 if (HeHASH(entry) != hash) /* strings can't be equal */
2687 if (HeKLEN(entry) != len)
2689 if (HeKEY(entry) != str && memNE(HeKEY(entry),str,len)) /* is this it? */
2691 if (HeKFLAGS(entry) != flags_masked)
2698 if (--entry->he_valu.hent_refcount == 0) {
2699 *oentry = HeNEXT(entry);
2701 xhv->xhv_keys--; /* HvTOTALKEYS(hv)-- */
2706 Perl_ck_warner_d(aTHX_ packWARN(WARN_INTERNAL),
2707 "Attempt to free non-existent shared string '%s'%s"
2709 hek ? HEK_KEY(hek) : str,
2710 ((k_flags & HVhek_UTF8) ? " (utf8)" : "") pTHX__VALUE);
2711 if (k_flags & HVhek_FREEKEY)
2715 /* get a (constant) string ptr from the global string table
2716 * string will get added if it is not already there.
2717 * len and hash must both be valid for str.
2720 Perl_share_hek(pTHX_ const char *str, I32 len, register U32 hash)
2722 bool is_utf8 = FALSE;
2724 const char * const save = str;
2726 PERL_ARGS_ASSERT_SHARE_HEK;
2729 STRLEN tmplen = -len;
2731 /* See the note in hv_fetch(). --jhi */
2732 str = (char*)bytes_from_utf8((U8*)str, &tmplen, &is_utf8);
2734 /* If we were able to downgrade here, then than means that we were passed
2735 in a key which only had chars 0-255, but was utf8 encoded. */
2738 /* If we found we were able to downgrade the string to bytes, then
2739 we should flag that it needs upgrading on keys or each. Also flag
2740 that we need share_hek_flags to free the string. */
2742 flags |= HVhek_WASUTF8 | HVhek_FREEKEY;
2745 return share_hek_flags (str, len, hash, flags);
2749 S_share_hek_flags(pTHX_ const char *str, I32 len, register U32 hash, int flags)
2753 const int flags_masked = flags & HVhek_MASK;
2754 const U32 hindex = hash & (I32) HvMAX(PL_strtab);
2755 register XPVHV * const xhv = (XPVHV*)SvANY(PL_strtab);
2757 PERL_ARGS_ASSERT_SHARE_HEK_FLAGS;
2759 /* what follows is the moral equivalent of:
2761 if (!(Svp = hv_fetch(PL_strtab, str, len, FALSE)))
2762 hv_store(PL_strtab, str, len, NULL, hash);
2764 Can't rehash the shared string table, so not sure if it's worth
2765 counting the number of entries in the linked list
2768 /* assert(xhv_array != 0) */
2769 entry = (HvARRAY(PL_strtab))[hindex];
2770 for (;entry; entry = HeNEXT(entry)) {
2771 if (HeHASH(entry) != hash) /* strings can't be equal */
2773 if (HeKLEN(entry) != len)
2775 if (HeKEY(entry) != str && memNE(HeKEY(entry),str,len)) /* is this it? */
2777 if (HeKFLAGS(entry) != flags_masked)
2783 /* What used to be head of the list.
2784 If this is NULL, then we're the first entry for this slot, which
2785 means we need to increate fill. */
2786 struct shared_he *new_entry;
2789 HE **const head = &HvARRAY(PL_strtab)[hindex];
2790 HE *const next = *head;
2792 /* We don't actually store a HE from the arena and a regular HEK.
2793 Instead we allocate one chunk of memory big enough for both,
2794 and put the HEK straight after the HE. This way we can find the
2795 HEK directly from the HE.
2798 Newx(k, STRUCT_OFFSET(struct shared_he,
2799 shared_he_hek.hek_key[0]) + len + 2, char);
2800 new_entry = (struct shared_he *)k;
2801 entry = &(new_entry->shared_he_he);
2802 hek = &(new_entry->shared_he_hek);
2804 Copy(str, HEK_KEY(hek), len, char);
2805 HEK_KEY(hek)[len] = 0;
2807 HEK_HASH(hek) = hash;
2808 HEK_FLAGS(hek) = (unsigned char)flags_masked;
2810 /* Still "point" to the HEK, so that other code need not know what
2812 HeKEY_hek(entry) = hek;
2813 entry->he_valu.hent_refcount = 0;
2814 HeNEXT(entry) = next;
2817 xhv->xhv_keys++; /* HvTOTALKEYS(hv)++ */
2818 if (!next) { /* initial entry? */
2819 } else if (xhv->xhv_keys > xhv->xhv_max /* HvKEYS(hv) > HvMAX(hv) */) {
2824 ++entry->he_valu.hent_refcount;
2826 if (flags & HVhek_FREEKEY)
2829 return HeKEY_hek(entry);
2833 Perl_hv_placeholders_p(pTHX_ HV *hv)
2836 MAGIC *mg = mg_find((const SV *)hv, PERL_MAGIC_rhash);
2838 PERL_ARGS_ASSERT_HV_PLACEHOLDERS_P;
2841 mg = sv_magicext(MUTABLE_SV(hv), 0, PERL_MAGIC_rhash, 0, 0, 0);
2844 Perl_die(aTHX_ "panic: hv_placeholders_p");
2847 return &(mg->mg_len);
2852 Perl_hv_placeholders_get(pTHX_ const HV *hv)
2855 MAGIC * const mg = mg_find((const SV *)hv, PERL_MAGIC_rhash);
2857 PERL_ARGS_ASSERT_HV_PLACEHOLDERS_GET;
2859 return mg ? mg->mg_len : 0;
2863 Perl_hv_placeholders_set(pTHX_ HV *hv, I32 ph)
2866 MAGIC * const mg = mg_find((const SV *)hv, PERL_MAGIC_rhash);
2868 PERL_ARGS_ASSERT_HV_PLACEHOLDERS_SET;
2873 if (!sv_magicext(MUTABLE_SV(hv), 0, PERL_MAGIC_rhash, 0, 0, ph))
2874 Perl_die(aTHX_ "panic: hv_placeholders_set");
2876 /* else we don't need to add magic to record 0 placeholders. */
2880 S_refcounted_he_value(pTHX_ const struct refcounted_he *he)
2885 PERL_ARGS_ASSERT_REFCOUNTED_HE_VALUE;
2887 switch(he->refcounted_he_data[0] & HVrhek_typemask) {
2892 value = &PL_sv_placeholder;
2895 value = newSViv(he->refcounted_he_val.refcounted_he_u_iv);
2898 value = newSVuv(he->refcounted_he_val.refcounted_he_u_uv);
2901 case HVrhek_PV_UTF8:
2902 /* Create a string SV that directly points to the bytes in our
2904 value = newSV_type(SVt_PV);
2905 SvPV_set(value, (char *) he->refcounted_he_data + 1);
2906 SvCUR_set(value, he->refcounted_he_val.refcounted_he_u_len);
2907 /* This stops anything trying to free it */
2908 SvLEN_set(value, 0);
2910 SvREADONLY_on(value);
2911 if ((he->refcounted_he_data[0] & HVrhek_typemask) == HVrhek_PV_UTF8)
2915 Perl_croak(aTHX_ "panic: refcounted_he_value bad flags %"UVxf,
2916 (UV)he->refcounted_he_data[0]);
2922 =for apidoc m|HV *|refcounted_he_chain_2hv|const struct refcounted_he *c|U32 flags
2924 Generates and returns a C<HV *> representing the content of a
2925 C<refcounted_he> chain.
2926 I<flags> is currently unused and must be zero.
2931 Perl_refcounted_he_chain_2hv(pTHX_ const struct refcounted_he *chain, U32 flags)
2935 U32 placeholders, max;
2938 Perl_croak(aTHX_ "panic: refcounted_he_chain_2hv bad flags %"UVxf,
2941 /* We could chase the chain once to get an idea of the number of keys,
2942 and call ksplit. But for now we'll make a potentially inefficient
2943 hash with only 8 entries in its array. */
2948 Newxz(array, PERL_HV_ARRAY_ALLOC_BYTES(max + 1), char);
2949 HvARRAY(hv) = (HE**)array;
2955 U32 hash = chain->refcounted_he_hash;
2957 U32 hash = HEK_HASH(chain->refcounted_he_hek);
2959 HE **oentry = &((HvARRAY(hv))[hash & max]);
2960 HE *entry = *oentry;
2963 for (; entry; entry = HeNEXT(entry)) {
2964 if (HeHASH(entry) == hash) {
2965 /* We might have a duplicate key here. If so, entry is older
2966 than the key we've already put in the hash, so if they are
2967 the same, skip adding entry. */
2969 const STRLEN klen = HeKLEN(entry);
2970 const char *const key = HeKEY(entry);
2971 if (klen == chain->refcounted_he_keylen
2972 && (!!HeKUTF8(entry)
2973 == !!(chain->refcounted_he_data[0] & HVhek_UTF8))
2974 && memEQ(key, REF_HE_KEY(chain), klen))
2977 if (HeKEY_hek(entry) == chain->refcounted_he_hek)
2979 if (HeKLEN(entry) == HEK_LEN(chain->refcounted_he_hek)
2980 && HeKUTF8(entry) == HEK_UTF8(chain->refcounted_he_hek)
2981 && memEQ(HeKEY(entry), HEK_KEY(chain->refcounted_he_hek),
2992 = share_hek_flags(REF_HE_KEY(chain),
2993 chain->refcounted_he_keylen,
2994 chain->refcounted_he_hash,
2995 (chain->refcounted_he_data[0]
2996 & (HVhek_UTF8|HVhek_WASUTF8)));
2998 HeKEY_hek(entry) = share_hek_hek(chain->refcounted_he_hek);
3000 value = refcounted_he_value(chain);
3001 if (value == &PL_sv_placeholder)
3003 HeVAL(entry) = value;
3005 /* Link it into the chain. */
3006 HeNEXT(entry) = *oentry;
3012 chain = chain->refcounted_he_next;
3016 clear_placeholders(hv, placeholders);
3017 HvTOTALKEYS(hv) -= placeholders;
3020 /* We could check in the loop to see if we encounter any keys with key
3021 flags, but it's probably not worth it, as this per-hash flag is only
3022 really meant as an optimisation for things like Storable. */
3024 DEBUG_A(Perl_hv_assert(aTHX_ hv));
3030 =for apidoc m|SV *|refcounted_he_fetch_pvn|const struct refcounted_he *chain|const char *keypv|STRLEN keylen|U32 hash|U32 flags
3032 Search along a C<refcounted_he> chain for an entry with the key specified
3033 by I<keypv> and I<keylen>. If I<flags> has the C<REFCOUNTED_HE_KEY_UTF8>
3034 bit set, the key octets are interpreted as UTF-8, otherwise they
3035 are interpreted as Latin-1. I<hash> is a precomputed hash of the key
3036 string, or zero if it has not been precomputed. Returns a mortal scalar
3037 representing the value associated with the key, or C<&PL_sv_placeholder>
3038 if there is no value associated with the key.
3044 Perl_refcounted_he_fetch_pvn(pTHX_ const struct refcounted_he *chain,
3045 const char *keypv, STRLEN keylen, U32 hash, U32 flags)
3049 PERL_ARGS_ASSERT_REFCOUNTED_HE_FETCH_PVN;
3051 if (flags & ~REFCOUNTED_HE_KEY_UTF8)
3052 Perl_croak(aTHX_ "panic: refcounted_he_fetch_pvn bad flags %"UVxf,
3055 return &PL_sv_placeholder;
3056 if (flags & REFCOUNTED_HE_KEY_UTF8) {
3057 /* For searching purposes, canonicalise to Latin-1 where possible. */
3058 const char *keyend = keypv + keylen, *p;
3059 STRLEN nonascii_count = 0;
3060 for (p = keypv; p != keyend; p++) {
3063 if (!((c & 0xfe) == 0xc2 && ++p != keyend &&
3064 (((U8)*p) & 0xc0) == 0x80))
3065 goto canonicalised_key;
3069 if (nonascii_count) {
3071 const char *p = keypv, *keyend = keypv + keylen;
3072 keylen -= nonascii_count;
3073 Newx(q, keylen, char);
3076 for (; p != keyend; p++, q++) {
3079 ((c & 0x80) ? ((c & 0x03) << 6) | (((U8)*++p) & 0x3f) : c);
3082 flags &= ~REFCOUNTED_HE_KEY_UTF8;
3083 canonicalised_key: ;
3085 utf8_flag = (flags & REFCOUNTED_HE_KEY_UTF8) ? HVhek_UTF8 : 0;
3087 PERL_HASH(hash, keypv, keylen);
3089 for (; chain; chain = chain->refcounted_he_next) {
3092 hash == chain->refcounted_he_hash &&
3093 keylen == chain->refcounted_he_keylen &&
3094 memEQ(REF_HE_KEY(chain), keypv, keylen) &&
3095 utf8_flag == (chain->refcounted_he_data[0] & HVhek_UTF8)
3097 hash == HEK_HASH(chain->refcounted_he_hek) &&
3098 keylen == (STRLEN)HEK_LEN(chain->refcounted_he_hek) &&
3099 memEQ(HEK_KEY(chain->refcounted_he_hek), keypv, keylen) &&
3100 utf8_flag == (HEK_FLAGS(chain->refcounted_he_hek) & HVhek_UTF8)
3103 return sv_2mortal(refcounted_he_value(chain));
3105 return &PL_sv_placeholder;
3109 =for apidoc m|SV *|refcounted_he_fetch_pv|const struct refcounted_he *chain|const char *key|U32 hash|U32 flags
3111 Like L</refcounted_he_fetch_pvn>, but takes a nul-terminated string
3112 instead of a string/length pair.
3118 Perl_refcounted_he_fetch_pv(pTHX_ const struct refcounted_he *chain,
3119 const char *key, U32 hash, U32 flags)
3121 PERL_ARGS_ASSERT_REFCOUNTED_HE_FETCH_PV;
3122 return refcounted_he_fetch_pvn(chain, key, strlen(key), hash, flags);
3126 =for apidoc m|SV *|refcounted_he_fetch_sv|const struct refcounted_he *chain|SV *key|U32 hash|U32 flags
3128 Like L</refcounted_he_fetch_pvn>, but takes a Perl scalar instead of a
3135 Perl_refcounted_he_fetch_sv(pTHX_ const struct refcounted_he *chain,
3136 SV *key, U32 hash, U32 flags)
3140 PERL_ARGS_ASSERT_REFCOUNTED_HE_FETCH_SV;
3141 if (flags & REFCOUNTED_HE_KEY_UTF8)
3142 Perl_croak(aTHX_ "panic: refcounted_he_fetch_sv bad flags %"UVxf,
3144 keypv = SvPV_const(key, keylen);
3146 flags |= REFCOUNTED_HE_KEY_UTF8;
3147 if (!hash && SvIsCOW_shared_hash(key))
3148 hash = SvSHARED_HASH(key);
3149 return refcounted_he_fetch_pvn(chain, keypv, keylen, hash, flags);
3153 =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
3155 Creates a new C<refcounted_he>. This consists of a single key/value
3156 pair and a reference to an existing C<refcounted_he> chain (which may
3157 be empty), and thus forms a longer chain. When using the longer chain,
3158 the new key/value pair takes precedence over any entry for the same key
3159 further along the chain.
3161 The new key is specified by I<keypv> and I<keylen>. If I<flags> has
3162 the C<REFCOUNTED_HE_KEY_UTF8> bit set, the key octets are interpreted
3163 as UTF-8, otherwise they are interpreted as Latin-1. I<hash> is
3164 a precomputed hash of the key string, or zero if it has not been
3167 I<value> is the scalar value to store for this key. I<value> is copied
3168 by this function, which thus does not take ownership of any reference
3169 to it, and later changes to the scalar will not be reflected in the
3170 value visible in the C<refcounted_he>. Complex types of scalar will not
3171 be stored with referential integrity, but will be coerced to strings.
3172 I<value> may be either null or C<&PL_sv_placeholder> to indicate that no
3173 value is to be associated with the key; this, as with any non-null value,
3174 takes precedence over the existence of a value for the key further along
3177 I<parent> points to the rest of the C<refcounted_he> chain to be
3178 attached to the new C<refcounted_he>. This function takes ownership
3179 of one reference to I<parent>, and returns one reference to the new
3185 struct refcounted_he *
3186 Perl_refcounted_he_new_pvn(pTHX_ struct refcounted_he *parent,
3187 const char *keypv, STRLEN keylen, U32 hash, SV *value, U32 flags)
3190 STRLEN value_len = 0;
3191 const char *value_p = NULL;
3195 STRLEN key_offset = 1;
3196 struct refcounted_he *he;
3197 PERL_ARGS_ASSERT_REFCOUNTED_HE_NEW_PVN;
3199 if (!value || value == &PL_sv_placeholder) {
3200 value_type = HVrhek_delete;
3201 } else if (SvPOK(value)) {
3202 value_type = HVrhek_PV;
3203 } else if (SvIOK(value)) {
3204 value_type = SvUOK((const SV *)value) ? HVrhek_UV : HVrhek_IV;
3205 } else if (!SvOK(value)) {
3206 value_type = HVrhek_undef;
3208 value_type = HVrhek_PV;
3210 is_pv = value_type == HVrhek_PV;
3212 /* Do it this way so that the SvUTF8() test is after the SvPV, in case
3213 the value is overloaded, and doesn't yet have the UTF-8flag set. */
3214 value_p = SvPV_const(value, value_len);
3216 value_type = HVrhek_PV_UTF8;
3217 key_offset = value_len + 2;
3219 hekflags = value_type;
3221 if (flags & REFCOUNTED_HE_KEY_UTF8) {
3222 /* Canonicalise to Latin-1 where possible. */
3223 const char *keyend = keypv + keylen, *p;
3224 STRLEN nonascii_count = 0;
3225 for (p = keypv; p != keyend; p++) {
3228 if (!((c & 0xfe) == 0xc2 && ++p != keyend &&
3229 (((U8)*p) & 0xc0) == 0x80))
3230 goto canonicalised_key;
3234 if (nonascii_count) {
3236 const char *p = keypv, *keyend = keypv + keylen;
3237 keylen -= nonascii_count;
3238 Newx(q, keylen, char);
3241 for (; p != keyend; p++, q++) {
3244 ((c & 0x80) ? ((c & 0x03) << 6) | (((U8)*++p) & 0x3f) : c);
3247 flags &= ~REFCOUNTED_HE_KEY_UTF8;
3248 canonicalised_key: ;
3250 if (flags & REFCOUNTED_HE_KEY_UTF8)
3251 hekflags |= HVhek_UTF8;
3253 PERL_HASH(hash, keypv, keylen);
3256 he = (struct refcounted_he*)
3257 PerlMemShared_malloc(sizeof(struct refcounted_he) - 1
3261 he = (struct refcounted_he*)
3262 PerlMemShared_malloc(sizeof(struct refcounted_he) - 1
3266 he->refcounted_he_next = parent;
3269 Copy(value_p, he->refcounted_he_data + 1, value_len + 1, char);
3270 he->refcounted_he_val.refcounted_he_u_len = value_len;
3271 } else if (value_type == HVrhek_IV) {
3272 he->refcounted_he_val.refcounted_he_u_iv = SvIVX(value);
3273 } else if (value_type == HVrhek_UV) {
3274 he->refcounted_he_val.refcounted_he_u_uv = SvUVX(value);
3278 he->refcounted_he_hash = hash;
3279 he->refcounted_he_keylen = keylen;
3280 Copy(keypv, he->refcounted_he_data + key_offset, keylen, char);
3282 he->refcounted_he_hek = share_hek_flags(keypv, keylen, hash, hekflags);
3285 he->refcounted_he_data[0] = hekflags;
3286 he->refcounted_he_refcnt = 1;
3292 =for apidoc m|struct refcounted_he *|refcounted_he_new_pv|struct refcounted_he *parent|const char *key|U32 hash|SV *value|U32 flags
3294 Like L</refcounted_he_new_pvn>, but takes a nul-terminated string instead
3295 of a string/length pair.
3300 struct refcounted_he *
3301 Perl_refcounted_he_new_pv(pTHX_ struct refcounted_he *parent,
3302 const char *key, U32 hash, SV *value, U32 flags)
3304 PERL_ARGS_ASSERT_REFCOUNTED_HE_NEW_PV;
3305 return refcounted_he_new_pvn(parent, key, strlen(key), hash, value, flags);
3309 =for apidoc m|struct refcounted_he *|refcounted_he_new_sv|struct refcounted_he *parent|SV *key|U32 hash|SV *value|U32 flags
3311 Like L</refcounted_he_new_pvn>, but takes a Perl scalar instead of a
3317 struct refcounted_he *
3318 Perl_refcounted_he_new_sv(pTHX_ struct refcounted_he *parent,
3319 SV *key, U32 hash, SV *value, U32 flags)
3323 PERL_ARGS_ASSERT_REFCOUNTED_HE_NEW_SV;
3324 if (flags & REFCOUNTED_HE_KEY_UTF8)
3325 Perl_croak(aTHX_ "panic: refcounted_he_new_sv bad flags %"UVxf,
3327 keypv = SvPV_const(key, keylen);
3329 flags |= REFCOUNTED_HE_KEY_UTF8;
3330 if (!hash && SvIsCOW_shared_hash(key))
3331 hash = SvSHARED_HASH(key);
3332 return refcounted_he_new_pvn(parent, keypv, keylen, hash, value, flags);
3336 =for apidoc m|void|refcounted_he_free|struct refcounted_he *he
3338 Decrements the reference count of a C<refcounted_he> by one. If the
3339 reference count reaches zero the structure's memory is freed, which
3340 (recursively) causes a reduction of its parent C<refcounted_he>'s
3341 reference count. It is safe to pass a null pointer to this function:
3342 no action occurs in this case.
3348 Perl_refcounted_he_free(pTHX_ struct refcounted_he *he) {
3350 PERL_UNUSED_CONTEXT;
3353 struct refcounted_he *copy;
3357 new_count = --he->refcounted_he_refcnt;
3358 HINTS_REFCNT_UNLOCK;
3364 #ifndef USE_ITHREADS
3365 unshare_hek_or_pvn (he->refcounted_he_hek, 0, 0, 0);
3368 he = he->refcounted_he_next;
3369 PerlMemShared_free(copy);
3374 =for apidoc m|struct refcounted_he *|refcounted_he_inc|struct refcounted_he *he
3376 Increment the reference count of a C<refcounted_he>. The pointer to the
3377 C<refcounted_he> is also returned. It is safe to pass a null pointer
3378 to this function: no action occurs and a null pointer is returned.
3383 struct refcounted_he *
3384 Perl_refcounted_he_inc(pTHX_ struct refcounted_he *he)
3388 he->refcounted_he_refcnt++;
3389 HINTS_REFCNT_UNLOCK;
3394 /* pp_entereval is aware that labels are stored with a key ':' at the top of
3397 Perl_fetch_cop_label(pTHX_ COP *const cop, STRLEN *len, U32 *flags) {
3398 struct refcounted_he *const chain = cop->cop_hints_hash;
3400 PERL_ARGS_ASSERT_FETCH_COP_LABEL;
3405 if (chain->refcounted_he_keylen != 1)
3407 if (*REF_HE_KEY(chain) != ':')
3410 if ((STRLEN)HEK_LEN(chain->refcounted_he_hek) != 1)
3412 if (*HEK_KEY(chain->refcounted_he_hek) != ':')
3415 /* Stop anyone trying to really mess us up by adding their own value for
3417 if ((chain->refcounted_he_data[0] & HVrhek_typemask) != HVrhek_PV
3418 && (chain->refcounted_he_data[0] & HVrhek_typemask) != HVrhek_PV_UTF8)
3422 *len = chain->refcounted_he_val.refcounted_he_u_len;
3424 *flags = ((chain->refcounted_he_data[0] & HVrhek_typemask)
3425 == HVrhek_PV_UTF8) ? SVf_UTF8 : 0;
3427 return chain->refcounted_he_data + 1;
3431 Perl_store_cop_label(pTHX_ COP *const cop, const char *label, STRLEN len,
3435 PERL_ARGS_ASSERT_STORE_COP_LABEL;
3437 if (flags & ~(SVf_UTF8))
3438 Perl_croak(aTHX_ "panic: store_cop_label illegal flag bits 0x%" UVxf,
3440 labelsv = newSVpvn_flags(label, len, SVs_TEMP);
3441 if (flags & SVf_UTF8)
3444 = refcounted_he_new_pvs(cop->cop_hints_hash, ":", labelsv, 0);
3448 =for apidoc hv_assert
3450 Check that a hash is in an internally consistent state.
3458 Perl_hv_assert(pTHX_ HV *hv)
3463 int placeholders = 0;
3466 const I32 riter = HvRITER_get(hv);
3467 HE *eiter = HvEITER_get(hv);
3469 PERL_ARGS_ASSERT_HV_ASSERT;
3471 (void)hv_iterinit(hv);
3473 while ((entry = hv_iternext_flags(hv, HV_ITERNEXT_WANTPLACEHOLDERS))) {
3474 /* sanity check the values */
3475 if (HeVAL(entry) == &PL_sv_placeholder)
3479 /* sanity check the keys */
3480 if (HeSVKEY(entry)) {
3481 NOOP; /* Don't know what to check on SV keys. */
3482 } else if (HeKUTF8(entry)) {
3484 if (HeKWASUTF8(entry)) {
3485 PerlIO_printf(Perl_debug_log,
3486 "hash key has both WASUTF8 and UTF8: '%.*s'\n",
3487 (int) HeKLEN(entry), HeKEY(entry));
3490 } else if (HeKWASUTF8(entry))
3493 if (!SvTIED_mg((const SV *)hv, PERL_MAGIC_tied)) {
3494 static const char bad_count[] = "Count %d %s(s), but hash reports %d\n";
3495 const int nhashkeys = HvUSEDKEYS(hv);
3496 const int nhashplaceholders = HvPLACEHOLDERS_get(hv);
3498 if (nhashkeys != real) {
3499 PerlIO_printf(Perl_debug_log, bad_count, real, "keys", nhashkeys );
3502 if (nhashplaceholders != placeholders) {
3503 PerlIO_printf(Perl_debug_log, bad_count, placeholders, "placeholder", nhashplaceholders );
3507 if (withflags && ! HvHASKFLAGS(hv)) {
3508 PerlIO_printf(Perl_debug_log,
3509 "Hash has HASKFLAGS off but I count %d key(s) with flags\n",
3514 sv_dump(MUTABLE_SV(hv));
3516 HvRITER_set(hv, riter); /* Restore hash iterator state */
3517 HvEITER_set(hv, eiter);
3524 * c-indentation-style: bsd
3526 * indent-tabs-mode: t
3529 * ex: set ts=8 sts=4 sw=4 noet: