This is a live mirror of the Perl 5 development currently hosted at https://github.com/perl/perl5
fix eval qw(BEGIN{die}) style leaks.
[perl5.git] / hv.c
CommitLineData
a0d0e21e 1/* hv.c
79072805 2 *
4bb101f2 3 * Copyright (C) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
b94e2f88 4 * 2000, 2001, 2002, 2003, 2004, 2005, 2006, by Larry Wall and others
79072805
LW
5 *
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.
8 *
a0d0e21e
LW
9 */
10
11/*
12 * "I sit beside the fire and think of all that I have seen." --Bilbo
79072805
LW
13 */
14
d5afce77
RB
15/*
16=head1 Hash Manipulation Functions
166f8a29
DM
17
18A HV structure represents a Perl hash. It consists mainly of an array
19of pointers, each of which points to a linked list of HE structures. The
20array is indexed by the hash function of the key, so each linked list
21represents all the hash entries with the same hash value. Each HE contains
22a pointer to the actual value, plus a pointer to a HEK structure which
23holds the key and hash value.
24
25=cut
26
d5afce77
RB
27*/
28
79072805 29#include "EXTERN.h"
864dbfa3 30#define PERL_IN_HV_C
3d78eb94 31#define PERL_HASH_INTERNAL_ACCESS
79072805
LW
32#include "perl.h"
33
d8012aaf 34#define HV_MAX_LENGTH_BEFORE_SPLIT 14
fdcd69b6 35
d75ce684 36static const char S_strtab_error[]
5d2b1485
NC
37 = "Cannot modify shared string table in hv_%s";
38
cac9b346
NC
39STATIC void
40S_more_he(pTHX)
41{
97aff369 42 dVAR;
cac9b346
NC
43 HE* he;
44 HE* heend;
5e258f8c
JC
45
46 he = (HE*) Perl_get_arena(aTHX_ PERL_ARENA_SIZE);
cac9b346
NC
47
48 heend = &he[PERL_ARENA_SIZE / sizeof(HE) - 1];
d2a0f284 49 PL_body_roots[HE_SVSLOT] = he;
cac9b346
NC
50 while (he < heend) {
51 HeNEXT(he) = (HE*)(he + 1);
52 he++;
53 }
54 HeNEXT(he) = 0;
55}
56
c941fb51
NC
57#ifdef PURIFY
58
59#define new_HE() (HE*)safemalloc(sizeof(HE))
60#define del_HE(p) safefree((char*)p)
61
62#else
63
76e3520e 64STATIC HE*
cea2e8a9 65S_new_he(pTHX)
4633a7c4 66{
97aff369 67 dVAR;
4633a7c4 68 HE* he;
0bd48802 69 void ** const root = &PL_body_roots[HE_SVSLOT];
6a93a7e5 70
333f433b 71 LOCK_SV_MUTEX;
6a93a7e5 72 if (!*root)
cac9b346 73 S_more_he(aTHX);
6a93a7e5 74 he = *root;
ce3e5c45 75 assert(he);
6a93a7e5 76 *root = HeNEXT(he);
333f433b
DG
77 UNLOCK_SV_MUTEX;
78 return he;
4633a7c4
LW
79}
80
c941fb51
NC
81#define new_HE() new_he()
82#define del_HE(p) \
83 STMT_START { \
84 LOCK_SV_MUTEX; \
6a93a7e5
NC
85 HeNEXT(p) = (HE*)(PL_body_roots[HE_SVSLOT]); \
86 PL_body_roots[HE_SVSLOT] = p; \
c941fb51
NC
87 UNLOCK_SV_MUTEX; \
88 } STMT_END
d33b2eba 89
d33b2eba 90
d33b2eba
GS
91
92#endif
93
76e3520e 94STATIC HEK *
5f66b61c 95S_save_hek_flags(const char *str, I32 len, U32 hash, int flags)
bbce6d69 96{
35a4481c 97 const int flags_masked = flags & HVhek_MASK;
bbce6d69
PP
98 char *k;
99 register HEK *hek;
1c846c1f 100
a02a5408 101 Newx(k, HEK_BASESIZE + len + 2, char);
bbce6d69 102 hek = (HEK*)k;
ff68c719 103 Copy(str, HEK_KEY(hek), len, char);
e05949c7 104 HEK_KEY(hek)[len] = 0;
ff68c719
PP
105 HEK_LEN(hek) = len;
106 HEK_HASH(hek) = hash;
45e34800 107 HEK_FLAGS(hek) = (unsigned char)flags_masked | HVhek_UNSHARED;
dcf933a4
NC
108
109 if (flags & HVhek_FREEKEY)
110 Safefree(str);
bbce6d69
PP
111 return hek;
112}
113
4a31713e 114/* free the pool of temporary HE/HEK pairs returned by hv_fetch_ent
dd28f7bb
DM
115 * for tied hashes */
116
117void
118Perl_free_tied_hv_pool(pTHX)
119{
97aff369 120 dVAR;
dd28f7bb
DM
121 HE *he = PL_hv_fetch_ent_mh;
122 while (he) {
9d4ba2ae 123 HE * const ohe = he;
dd28f7bb 124 Safefree(HeKEY_hek(he));
dd28f7bb
DM
125 he = HeNEXT(he);
126 del_HE(ohe);
127 }
4608196e 128 PL_hv_fetch_ent_mh = NULL;
dd28f7bb
DM
129}
130
d18c6117 131#if defined(USE_ITHREADS)
0bff533c
NC
132HEK *
133Perl_hek_dup(pTHX_ HEK *source, CLONE_PARAMS* param)
134{
658b4a4a 135 HEK *shared = (HEK*)ptr_table_fetch(PL_ptr_table, source);
9d4ba2ae
AL
136
137 PERL_UNUSED_ARG(param);
0bff533c
NC
138
139 if (shared) {
140 /* We already shared this hash key. */
454f1e26 141 (void)share_hek_hek(shared);
0bff533c
NC
142 }
143 else {
658b4a4a 144 shared
6e838c70
NC
145 = share_hek_flags(HEK_KEY(source), HEK_LEN(source),
146 HEK_HASH(source), HEK_FLAGS(source));
658b4a4a 147 ptr_table_store(PL_ptr_table, source, shared);
0bff533c 148 }
658b4a4a 149 return shared;
0bff533c
NC
150}
151
d18c6117 152HE *
5c4138a0 153Perl_he_dup(pTHX_ const HE *e, bool shared, CLONE_PARAMS* param)
d18c6117
GS
154{
155 HE *ret;
156
157 if (!e)
4608196e 158 return NULL;
7766f137
GS
159 /* look for it in the table first */
160 ret = (HE*)ptr_table_fetch(PL_ptr_table, e);
161 if (ret)
162 return ret;
163
164 /* create anew and remember what it is */
d33b2eba 165 ret = new_HE();
7766f137
GS
166 ptr_table_store(PL_ptr_table, e, ret);
167
d2d73c3e 168 HeNEXT(ret) = he_dup(HeNEXT(e),shared, param);
dd28f7bb
DM
169 if (HeKLEN(e) == HEf_SVKEY) {
170 char *k;
a02a5408 171 Newx(k, HEK_BASESIZE + sizeof(SV*), char);
dd28f7bb 172 HeKEY_hek(ret) = (HEK*)k;
d2d73c3e 173 HeKEY_sv(ret) = SvREFCNT_inc(sv_dup(HeKEY_sv(e), param));
dd28f7bb 174 }
c21d1a0f 175 else if (shared) {
0bff533c
NC
176 /* This is hek_dup inlined, which seems to be important for speed
177 reasons. */
1b6737cc 178 HEK * const source = HeKEY_hek(e);
658b4a4a 179 HEK *shared = (HEK*)ptr_table_fetch(PL_ptr_table, source);
c21d1a0f
NC
180
181 if (shared) {
182 /* We already shared this hash key. */
454f1e26 183 (void)share_hek_hek(shared);
c21d1a0f
NC
184 }
185 else {
658b4a4a 186 shared
6e838c70
NC
187 = share_hek_flags(HEK_KEY(source), HEK_LEN(source),
188 HEK_HASH(source), HEK_FLAGS(source));
658b4a4a 189 ptr_table_store(PL_ptr_table, source, shared);
c21d1a0f 190 }
658b4a4a 191 HeKEY_hek(ret) = shared;
c21d1a0f 192 }
d18c6117 193 else
19692e8d
NC
194 HeKEY_hek(ret) = save_hek_flags(HeKEY(e), HeKLEN(e), HeHASH(e),
195 HeKFLAGS(e));
d2d73c3e 196 HeVAL(ret) = SvREFCNT_inc(sv_dup(HeVAL(e), param));
d18c6117
GS
197 return ret;
198}
199#endif /* USE_ITHREADS */
200
1b1f1335 201static void
2393f1b9
JH
202S_hv_notallowed(pTHX_ int flags, const char *key, I32 klen,
203 const char *msg)
1b1f1335 204{
1b6737cc 205 SV * const sv = sv_newmortal();
19692e8d 206 if (!(flags & HVhek_FREEKEY)) {
1b1f1335
NIS
207 sv_setpvn(sv, key, klen);
208 }
209 else {
210 /* Need to free saved eventually assign to mortal SV */
34c3c4e3 211 /* XXX is this line an error ???: SV *sv = sv_newmortal(); */
1b1f1335
NIS
212 sv_usepvn(sv, (char *) key, klen);
213 }
19692e8d 214 if (flags & HVhek_UTF8) {
1b1f1335
NIS
215 SvUTF8_on(sv);
216 }
c8cd6465 217 Perl_croak(aTHX_ msg, sv);
1b1f1335
NIS
218}
219
fde52b5c
PP
220/* (klen == HEf_SVKEY) is special for MAGICAL hv entries, meaning key slot
221 * contains an SV* */
222
34a6f7b4
NC
223#define HV_FETCH_ISSTORE 0x01
224#define HV_FETCH_ISEXISTS 0x02
225#define HV_FETCH_LVALUE 0x04
226#define HV_FETCH_JUST_SV 0x08
227
228/*
229=for apidoc hv_store
230
231Stores an SV in a hash. The hash key is specified as C<key> and C<klen> is
232the length of the key. The C<hash> parameter is the precomputed hash
233value; if it is zero then Perl will compute it. The return value will be
234NULL if the operation failed or if the value did not need to be actually
235stored within the hash (as in the case of tied hashes). Otherwise it can
236be dereferenced to get the original C<SV*>. Note that the caller is
237responsible for suitably incrementing the reference count of C<val> before
238the call, and decrementing it if the function returned NULL. Effectively
239a successful hv_store takes ownership of one reference to C<val>. This is
240usually what you want; a newly created SV has a reference count of one, so
241if all your code does is create SVs then store them in a hash, hv_store
242will own the only reference to the new SV, and your code doesn't need to do
243anything further to tidy up. hv_store is not implemented as a call to
244hv_store_ent, and does not create a temporary SV for the key, so if your
245key data is not already in SV form then use hv_store in preference to
246hv_store_ent.
247
248See L<perlguts/"Understanding the Magic of Tied Hashes and Arrays"> for more
249information on how to use this function on tied hashes.
250
251=cut
252*/
253
254SV**
255Perl_hv_store(pTHX_ HV *hv, const char *key, I32 klen_i32, SV *val, U32 hash)
256{
257 HE *hek;
258 STRLEN klen;
259 int flags;
260
261 if (klen_i32 < 0) {
262 klen = -klen_i32;
263 flags = HVhek_UTF8;
264 } else {
265 klen = klen_i32;
266 flags = 0;
267 }
268 hek = hv_fetch_common (hv, NULL, key, klen, flags,
52d01cc2 269 (HV_FETCH_ISSTORE|HV_FETCH_JUST_SV), val, hash);
34a6f7b4
NC
270 return hek ? &HeVAL(hek) : NULL;
271}
272
fabdb6c0 273/* XXX This looks like an ideal candidate to inline */
34a6f7b4
NC
274SV**
275Perl_hv_store_flags(pTHX_ HV *hv, const char *key, I32 klen, SV *val,
276 register U32 hash, int flags)
277{
9d4ba2ae 278 HE * const hek = hv_fetch_common (hv, NULL, key, klen, flags,
34a6f7b4
NC
279 (HV_FETCH_ISSTORE|HV_FETCH_JUST_SV), val, hash);
280 return hek ? &HeVAL(hek) : NULL;
281}
282
283/*
284=for apidoc hv_store_ent
285
286Stores C<val> in a hash. The hash key is specified as C<key>. The C<hash>
287parameter is the precomputed hash value; if it is zero then Perl will
288compute it. The return value is the new hash entry so created. It will be
289NULL if the operation failed or if the value did not need to be actually
290stored within the hash (as in the case of tied hashes). Otherwise the
291contents of the return value can be accessed using the C<He?> macros
292described here. Note that the caller is responsible for suitably
293incrementing the reference count of C<val> before the call, and
294decrementing it if the function returned NULL. Effectively a successful
295hv_store_ent takes ownership of one reference to C<val>. This is
296usually what you want; a newly created SV has a reference count of one, so
297if all your code does is create SVs then store them in a hash, hv_store
298will own the only reference to the new SV, and your code doesn't need to do
299anything further to tidy up. Note that hv_store_ent only reads the C<key>;
300unlike C<val> it does not take ownership of it, so maintaining the correct
301reference count on C<key> is entirely the caller's responsibility. hv_store
302is not implemented as a call to hv_store_ent, and does not create a temporary
303SV for the key, so if your key data is not already in SV form then use
304hv_store in preference to hv_store_ent.
305
306See L<perlguts/"Understanding the Magic of Tied Hashes and Arrays"> for more
307information on how to use this function on tied hashes.
308
309=cut
310*/
311
fabdb6c0 312/* XXX This looks like an ideal candidate to inline */
34a6f7b4
NC
313HE *
314Perl_hv_store_ent(pTHX_ HV *hv, SV *keysv, SV *val, U32 hash)
315{
316 return hv_fetch_common(hv, keysv, NULL, 0, 0, HV_FETCH_ISSTORE, val, hash);
317}
318
319/*
320=for apidoc hv_exists
321
322Returns a boolean indicating whether the specified hash key exists. The
323C<klen> is the length of the key.
324
325=cut
326*/
327
328bool
329Perl_hv_exists(pTHX_ HV *hv, const char *key, I32 klen_i32)
330{
331 STRLEN klen;
332 int flags;
333
334 if (klen_i32 < 0) {
335 klen = -klen_i32;
336 flags = HVhek_UTF8;
337 } else {
338 klen = klen_i32;
339 flags = 0;
340 }
341 return hv_fetch_common(hv, NULL, key, klen, flags, HV_FETCH_ISEXISTS, 0, 0)
342 ? TRUE : FALSE;
343}
344
954c1994
GS
345/*
346=for apidoc hv_fetch
347
348Returns the SV which corresponds to the specified key in the hash. The
349C<klen> is the length of the key. If C<lval> is set then the fetch will be
350part of a store. Check that the return value is non-null before
d1be9408 351dereferencing it to an C<SV*>.
954c1994 352
96f1132b 353See L<perlguts/"Understanding the Magic of Tied Hashes and Arrays"> for more
954c1994
GS
354information on how to use this function on tied hashes.
355
356=cut
357*/
358
79072805 359SV**
c1fe5510 360Perl_hv_fetch(pTHX_ HV *hv, const char *key, I32 klen_i32, I32 lval)
79072805 361{
c1fe5510
NC
362 HE *hek;
363 STRLEN klen;
364 int flags;
365
366 if (klen_i32 < 0) {
367 klen = -klen_i32;
368 flags = HVhek_UTF8;
369 } else {
370 klen = klen_i32;
371 flags = 0;
372 }
373 hek = hv_fetch_common (hv, NULL, key, klen, flags,
c445ea15 374 lval ? (HV_FETCH_JUST_SV | HV_FETCH_LVALUE) : HV_FETCH_JUST_SV,
a0714e2c 375 NULL, 0);
113738bb 376 return hek ? &HeVAL(hek) : NULL;
79072805
LW
377}
378
34a6f7b4
NC
379/*
380=for apidoc hv_exists_ent
381
382Returns a boolean indicating whether the specified hash key exists. C<hash>
383can be a valid precomputed hash value, or 0 to ask for it to be
384computed.
385
386=cut
387*/
388
fabdb6c0 389/* XXX This looks like an ideal candidate to inline */
34a6f7b4
NC
390bool
391Perl_hv_exists_ent(pTHX_ HV *hv, SV *keysv, U32 hash)
392{
393 return hv_fetch_common(hv, keysv, NULL, 0, 0, HV_FETCH_ISEXISTS, 0, hash)
394 ? TRUE : FALSE;
395}
396
d1be9408 397/* returns an HE * structure with the all fields set */
fde52b5c 398/* note that hent_val will be a mortal sv for MAGICAL hashes */
954c1994
GS
399/*
400=for apidoc hv_fetch_ent
401
402Returns the hash entry which corresponds to the specified key in the hash.
403C<hash> must be a valid precomputed hash number for the given C<key>, or 0
404if you want the function to compute it. IF C<lval> is set then the fetch
405will be part of a store. Make sure the return value is non-null before
406accessing it. The return value when C<tb> is a tied hash is a pointer to a
407static location, so be sure to make a copy of the structure if you need to
1c846c1f 408store it somewhere.
954c1994 409
96f1132b 410See L<perlguts/"Understanding the Magic of Tied Hashes and Arrays"> for more
954c1994
GS
411information on how to use this function on tied hashes.
412
413=cut
414*/
415
fde52b5c 416HE *
864dbfa3 417Perl_hv_fetch_ent(pTHX_ HV *hv, SV *keysv, I32 lval, register U32 hash)
fde52b5c 418{
7f66fda2 419 return hv_fetch_common(hv, keysv, NULL, 0, 0,
a0714e2c 420 (lval ? HV_FETCH_LVALUE : 0), NULL, hash);
113738bb
NC
421}
422
8f8d40ab 423STATIC HE *
c1fe5510 424S_hv_fetch_common(pTHX_ HV *hv, SV *keysv, const char *key, STRLEN klen,
b2c64049 425 int flags, int action, SV *val, register U32 hash)
113738bb 426{
27da23d5 427 dVAR;
b2c64049 428 XPVHV* xhv;
b2c64049
NC
429 HE *entry;
430 HE **oentry;
fde52b5c 431 SV *sv;
da58a35d 432 bool is_utf8;
113738bb 433 int masked_flags;
fde52b5c
PP
434
435 if (!hv)
a4fc7abc 436 return NULL;
fde52b5c 437
113738bb 438 if (keysv) {
e593d2fe
AE
439 if (flags & HVhek_FREEKEY)
440 Safefree(key);
5c144d81 441 key = SvPV_const(keysv, klen);
c1fe5510 442 flags = 0;
113738bb
NC
443 is_utf8 = (SvUTF8(keysv) != 0);
444 } else {
c1fe5510 445 is_utf8 = ((flags & HVhek_UTF8) ? TRUE : FALSE);
113738bb 446 }
113738bb 447
b2c64049 448 xhv = (XPVHV*)SvANY(hv);
7f66fda2 449 if (SvMAGICAL(hv)) {
6136c704 450 if (SvRMAGICAL(hv) && !(action & (HV_FETCH_ISSTORE|HV_FETCH_ISEXISTS))) {
7f66fda2
NC
451 if (mg_find((SV*)hv, PERL_MAGIC_tied) || SvGMAGICAL((SV*)hv)) {
452 sv = sv_newmortal();
113738bb 453
7f66fda2
NC
454 /* XXX should be able to skimp on the HE/HEK here when
455 HV_FETCH_JUST_SV is true. */
113738bb 456
7f66fda2
NC
457 if (!keysv) {
458 keysv = newSVpvn(key, klen);
459 if (is_utf8) {
460 SvUTF8_on(keysv);
461 }
462 } else {
463 keysv = newSVsv(keysv);
113738bb 464 }
7f66fda2
NC
465 mg_copy((SV*)hv, sv, (char *)keysv, HEf_SVKEY);
466
467 /* grab a fake HE/HEK pair from the pool or make a new one */
468 entry = PL_hv_fetch_ent_mh;
469 if (entry)
470 PL_hv_fetch_ent_mh = HeNEXT(entry);
471 else {
472 char *k;
473 entry = new_HE();
a02a5408 474 Newx(k, HEK_BASESIZE + sizeof(SV*), char);
7f66fda2
NC
475 HeKEY_hek(entry) = (HEK*)k;
476 }
4608196e 477 HeNEXT(entry) = NULL;
7f66fda2
NC
478 HeSVKEY_set(entry, keysv);
479 HeVAL(entry) = sv;
480 sv_upgrade(sv, SVt_PVLV);
481 LvTYPE(sv) = 'T';
482 /* so we can free entry when freeing sv */
483 LvTARG(sv) = (SV*)entry;
484
485 /* XXX remove at some point? */
486 if (flags & HVhek_FREEKEY)
487 Safefree(key);
488
489 return entry;
113738bb 490 }
7f66fda2
NC
491#ifdef ENV_IS_CASELESS
492 else if (mg_find((SV*)hv, PERL_MAGIC_env)) {
493 U32 i;
494 for (i = 0; i < klen; ++i)
495 if (isLOWER(key[i])) {
086cb327
NC
496 /* Would be nice if we had a routine to do the
497 copy and upercase in a single pass through. */
0bd48802 498 const char * const nkey = strupr(savepvn(key,klen));
086cb327
NC
499 /* Note that this fetch is for nkey (the uppercased
500 key) whereas the store is for key (the original) */
a0714e2c 501 entry = hv_fetch_common(hv, NULL, nkey, klen,
086cb327
NC
502 HVhek_FREEKEY, /* free nkey */
503 0 /* non-LVAL fetch */,
a0714e2c 504 NULL /* no value */,
086cb327
NC
505 0 /* compute hash */);
506 if (!entry && (action & HV_FETCH_LVALUE)) {
507 /* This call will free key if necessary.
508 Do it this way to encourage compiler to tail
509 call optimise. */
510 entry = hv_fetch_common(hv, keysv, key, klen,
511 flags, HV_FETCH_ISSTORE,
561b68a9 512 newSV(0), hash);
086cb327
NC
513 } else {
514 if (flags & HVhek_FREEKEY)
515 Safefree(key);
516 }
517 return entry;
7f66fda2 518 }
902173a3 519 }
7f66fda2
NC
520#endif
521 } /* ISFETCH */
522 else if (SvRMAGICAL(hv) && (action & HV_FETCH_ISEXISTS)) {
523 if (mg_find((SV*)hv, PERL_MAGIC_tied) || SvGMAGICAL((SV*)hv)) {
b2c64049
NC
524 /* I don't understand why hv_exists_ent has svret and sv,
525 whereas hv_exists only had one. */
9d4ba2ae 526 SV * const svret = sv_newmortal();
b2c64049 527 sv = sv_newmortal();
7f66fda2
NC
528
529 if (keysv || is_utf8) {
530 if (!keysv) {
531 keysv = newSVpvn(key, klen);
532 SvUTF8_on(keysv);
533 } else {
534 keysv = newSVsv(keysv);
535 }
b2c64049
NC
536 mg_copy((SV*)hv, sv, (char *)sv_2mortal(keysv), HEf_SVKEY);
537 } else {
538 mg_copy((SV*)hv, sv, key, klen);
7f66fda2 539 }
b2c64049
NC
540 if (flags & HVhek_FREEKEY)
541 Safefree(key);
7f66fda2
NC
542 magic_existspack(svret, mg_find(sv, PERL_MAGIC_tiedelem));
543 /* This cast somewhat evil, but I'm merely using NULL/
544 not NULL to return the boolean exists.
545 And I know hv is not NULL. */
546 return SvTRUE(svret) ? (HE *)hv : NULL;
e7152ba2 547 }
7f66fda2
NC
548#ifdef ENV_IS_CASELESS
549 else if (mg_find((SV*)hv, PERL_MAGIC_env)) {
550 /* XXX This code isn't UTF8 clean. */
a15d23f8 551 char * const keysave = (char * const)key;
b2c64049
NC
552 /* Will need to free this, so set FREEKEY flag. */
553 key = savepvn(key,klen);
554 key = (const char*)strupr((char*)key);
6136c704 555 is_utf8 = FALSE;
7f66fda2 556 hash = 0;
8b4f7dd5 557 keysv = 0;
b2c64049
NC
558
559 if (flags & HVhek_FREEKEY) {
560 Safefree(keysave);
561 }
562 flags |= HVhek_FREEKEY;
7f66fda2 563 }
902173a3 564#endif
7f66fda2 565 } /* ISEXISTS */
b2c64049
NC
566 else if (action & HV_FETCH_ISSTORE) {
567 bool needs_copy;
568 bool needs_store;
569 hv_magic_check (hv, &needs_copy, &needs_store);
570 if (needs_copy) {
a3b680e6 571 const bool save_taint = PL_tainted;
b2c64049
NC
572 if (keysv || is_utf8) {
573 if (!keysv) {
574 keysv = newSVpvn(key, klen);
575 SvUTF8_on(keysv);
576 }
577 if (PL_tainting)
578 PL_tainted = SvTAINTED(keysv);
579 keysv = sv_2mortal(newSVsv(keysv));
580 mg_copy((SV*)hv, val, (char*)keysv, HEf_SVKEY);
581 } else {
582 mg_copy((SV*)hv, val, key, klen);
583 }
584
585 TAINT_IF(save_taint);
1baaf5d7 586 if (!needs_store) {
b2c64049
NC
587 if (flags & HVhek_FREEKEY)
588 Safefree(key);
4608196e 589 return NULL;
b2c64049
NC
590 }
591#ifdef ENV_IS_CASELESS
592 else if (mg_find((SV*)hv, PERL_MAGIC_env)) {
593 /* XXX This code isn't UTF8 clean. */
594 const char *keysave = key;
595 /* Will need to free this, so set FREEKEY flag. */
596 key = savepvn(key,klen);
597 key = (const char*)strupr((char*)key);
6136c704 598 is_utf8 = FALSE;
b2c64049 599 hash = 0;
8b4f7dd5 600 keysv = 0;
b2c64049
NC
601
602 if (flags & HVhek_FREEKEY) {
603 Safefree(keysave);
604 }
605 flags |= HVhek_FREEKEY;
606 }
607#endif
608 }
609 } /* ISSTORE */
7f66fda2 610 } /* SvMAGICAL */
fde52b5c 611
7b2c381c 612 if (!HvARRAY(hv)) {
b2c64049 613 if ((action & (HV_FETCH_LVALUE | HV_FETCH_ISSTORE))
fde52b5c 614#ifdef DYNAMIC_ENV_FETCH /* if it's an %ENV lookup, we may get it on the fly */
8aacddc1 615 || (SvRMAGICAL((SV*)hv) && mg_find((SV*)hv, PERL_MAGIC_env))
fde52b5c 616#endif
d58e6666
NC
617 ) {
618 char *array;
a02a5408 619 Newxz(array,
cbec9347 620 PERL_HV_ARRAY_ALLOC_BYTES(xhv->xhv_max+1 /* HvMAX(hv)+1 */),
d58e6666
NC
621 char);
622 HvARRAY(hv) = (HE**)array;
623 }
7f66fda2
NC
624#ifdef DYNAMIC_ENV_FETCH
625 else if (action & HV_FETCH_ISEXISTS) {
626 /* for an %ENV exists, if we do an insert it's by a recursive
627 store call, so avoid creating HvARRAY(hv) right now. */
628 }
629#endif
113738bb
NC
630 else {
631 /* XXX remove at some point? */
632 if (flags & HVhek_FREEKEY)
633 Safefree(key);
634
fde52b5c 635 return 0;
113738bb 636 }
fde52b5c
PP
637 }
638
19692e8d 639 if (is_utf8) {
41d88b63 640 char * const keysave = (char *)key;
f9a63242 641 key = (char*)bytes_from_utf8((U8*)key, &klen, &is_utf8);
19692e8d 642 if (is_utf8)
c1fe5510
NC
643 flags |= HVhek_UTF8;
644 else
645 flags &= ~HVhek_UTF8;
7f66fda2
NC
646 if (key != keysave) {
647 if (flags & HVhek_FREEKEY)
648 Safefree(keysave);
19692e8d 649 flags |= HVhek_WASUTF8 | HVhek_FREEKEY;
7f66fda2 650 }
19692e8d 651 }
f9a63242 652
4b5190b5
NC
653 if (HvREHASH(hv)) {
654 PERL_HASH_INTERNAL(hash, key, klen);
b2c64049
NC
655 /* We don't have a pointer to the hv, so we have to replicate the
656 flag into every HEK, so that hv_iterkeysv can see it. */
657 /* And yes, you do need this even though you are not "storing" because
fdcd69b6
NC
658 you can flip the flags below if doing an lval lookup. (And that
659 was put in to give the semantics Andreas was expecting.) */
660 flags |= HVhek_REHASH;
4b5190b5 661 } else if (!hash) {
113738bb 662 if (keysv && (SvIsCOW_shared_hash(keysv))) {
c158a4fd 663 hash = SvSHARED_HASH(keysv);
46187eeb
NC
664 } else {
665 PERL_HASH(hash, key, klen);
666 }
667 }
effa1e2d 668
113738bb
NC
669 masked_flags = (flags & HVhek_MASK);
670
7f66fda2 671#ifdef DYNAMIC_ENV_FETCH
4608196e 672 if (!HvARRAY(hv)) entry = NULL;
7f66fda2
NC
673 else
674#endif
b2c64049 675 {
7b2c381c 676 entry = (HvARRAY(hv))[hash & (I32) HvMAX(hv)];
b2c64049 677 }
0298d7b9 678 for (; entry; entry = HeNEXT(entry)) {
fde52b5c
PP
679 if (HeHASH(entry) != hash) /* strings can't be equal */
680 continue;
eb160463 681 if (HeKLEN(entry) != (I32)klen)
fde52b5c 682 continue;
1c846c1f 683 if (HeKEY(entry) != key && memNE(HeKEY(entry),key,klen)) /* is this it? */
fde52b5c 684 continue;
113738bb 685 if ((HeKFLAGS(entry) ^ masked_flags) & HVhek_UTF8)
c3654f1a 686 continue;
b2c64049
NC
687
688 if (action & (HV_FETCH_LVALUE|HV_FETCH_ISSTORE)) {
689 if (HeKFLAGS(entry) != masked_flags) {
690 /* We match if HVhek_UTF8 bit in our flags and hash key's
691 match. But if entry was set previously with HVhek_WASUTF8
692 and key now doesn't (or vice versa) then we should change
693 the key's flag, as this is assignment. */
694 if (HvSHAREKEYS(hv)) {
695 /* Need to swap the key we have for a key with the flags we
696 need. As keys are shared we can't just write to the
697 flag, so we share the new one, unshare the old one. */
6136c704 698 HEK * const new_hek = share_hek_flags(key, klen, hash,
6e838c70 699 masked_flags);
b2c64049
NC
700 unshare_hek (HeKEY_hek(entry));
701 HeKEY_hek(entry) = new_hek;
702 }
5d2b1485
NC
703 else if (hv == PL_strtab) {
704 /* PL_strtab is usually the only hash without HvSHAREKEYS,
705 so putting this test here is cheap */
706 if (flags & HVhek_FREEKEY)
707 Safefree(key);
708 Perl_croak(aTHX_ S_strtab_error,
709 action & HV_FETCH_LVALUE ? "fetch" : "store");
710 }
b2c64049
NC
711 else
712 HeKFLAGS(entry) = masked_flags;
713 if (masked_flags & HVhek_ENABLEHVKFLAGS)
714 HvHASKFLAGS_on(hv);
715 }
716 if (HeVAL(entry) == &PL_sv_placeholder) {
717 /* yes, can store into placeholder slot */
718 if (action & HV_FETCH_LVALUE) {
719 if (SvMAGICAL(hv)) {
720 /* This preserves behaviour with the old hv_fetch
721 implementation which at this point would bail out
722 with a break; (at "if we find a placeholder, we
723 pretend we haven't found anything")
724
725 That break mean that if a placeholder were found, it
726 caused a call into hv_store, which in turn would
727 check magic, and if there is no magic end up pretty
728 much back at this point (in hv_store's code). */
729 break;
730 }
731 /* LVAL fetch which actaully needs a store. */
561b68a9 732 val = newSV(0);
ca732855 733 HvPLACEHOLDERS(hv)--;
b2c64049
NC
734 } else {
735 /* store */
736 if (val != &PL_sv_placeholder)
ca732855 737 HvPLACEHOLDERS(hv)--;
b2c64049
NC
738 }
739 HeVAL(entry) = val;
740 } else if (action & HV_FETCH_ISSTORE) {
741 SvREFCNT_dec(HeVAL(entry));
742 HeVAL(entry) = val;
743 }
27bcc0a7 744 } else if (HeVAL(entry) == &PL_sv_placeholder) {
b2c64049
NC
745 /* if we find a placeholder, we pretend we haven't found
746 anything */
8aacddc1 747 break;
b2c64049 748 }
113738bb
NC
749 if (flags & HVhek_FREEKEY)
750 Safefree(key);
fde52b5c
PP
751 return entry;
752 }
753#ifdef DYNAMIC_ENV_FETCH /* %ENV lookup? If so, try to fetch the value now */
0ed29950
NC
754 if (!(action & HV_FETCH_ISSTORE)
755 && SvRMAGICAL((SV*)hv) && mg_find((SV*)hv, PERL_MAGIC_env)) {
a6c40364 756 unsigned long len;
9d4ba2ae 757 const char * const env = PerlEnv_ENVgetenv_len(key,&len);
a6c40364
GS
758 if (env) {
759 sv = newSVpvn(env,len);
760 SvTAINTED_on(sv);
7fd3d16e 761 return hv_fetch_common(hv,keysv,key,klen,flags,HV_FETCH_ISSTORE,sv,
b2c64049 762 hash);
a6c40364 763 }
fde52b5c
PP
764 }
765#endif
7f66fda2
NC
766
767 if (!entry && SvREADONLY(hv) && !(action & HV_FETCH_ISEXISTS)) {
c445ea15 768 hv_notallowed(flags, key, klen,
c8cd6465
NC
769 "Attempt to access disallowed key '%"SVf"' in"
770 " a restricted hash");
1b1f1335 771 }
b2c64049
NC
772 if (!(action & (HV_FETCH_LVALUE|HV_FETCH_ISSTORE))) {
773 /* Not doing some form of store, so return failure. */
774 if (flags & HVhek_FREEKEY)
775 Safefree(key);
776 return 0;
777 }
113738bb 778 if (action & HV_FETCH_LVALUE) {
561b68a9 779 val = newSV(0);
b2c64049
NC
780 if (SvMAGICAL(hv)) {
781 /* At this point the old hv_fetch code would call to hv_store,
782 which in turn might do some tied magic. So we need to make that
783 magic check happen. */
784 /* gonna assign to this, so it better be there */
785 return hv_fetch_common(hv, keysv, key, klen, flags,
786 HV_FETCH_ISSTORE, val, hash);
787 /* XXX Surely that could leak if the fetch-was-store fails?
788 Just like the hv_fetch. */
113738bb
NC
789 }
790 }
791
b2c64049
NC
792 /* Welcome to hv_store... */
793
7b2c381c 794 if (!HvARRAY(hv)) {
b2c64049
NC
795 /* Not sure if we can get here. I think the only case of oentry being
796 NULL is for %ENV with dynamic env fetch. But that should disappear
797 with magic in the previous code. */
d58e6666 798 char *array;
a02a5408 799 Newxz(array,
b2c64049 800 PERL_HV_ARRAY_ALLOC_BYTES(xhv->xhv_max+1 /* HvMAX(hv)+1 */),
d58e6666
NC
801 char);
802 HvARRAY(hv) = (HE**)array;
b2c64049
NC
803 }
804
7b2c381c 805 oentry = &(HvARRAY(hv))[hash & (I32) xhv->xhv_max];
ab4af705 806
b2c64049
NC
807 entry = new_HE();
808 /* share_hek_flags will do the free for us. This might be considered
809 bad API design. */
810 if (HvSHAREKEYS(hv))
6e838c70 811 HeKEY_hek(entry) = share_hek_flags(key, klen, hash, flags);
5d2b1485
NC
812 else if (hv == PL_strtab) {
813 /* PL_strtab is usually the only hash without HvSHAREKEYS, so putting
814 this test here is cheap */
815 if (flags & HVhek_FREEKEY)
816 Safefree(key);
817 Perl_croak(aTHX_ S_strtab_error,
818 action & HV_FETCH_LVALUE ? "fetch" : "store");
819 }
b2c64049
NC
820 else /* gotta do the real thing */
821 HeKEY_hek(entry) = save_hek_flags(key, klen, hash, flags);
822 HeVAL(entry) = val;
823 HeNEXT(entry) = *oentry;
824 *oentry = entry;
825
826 if (val == &PL_sv_placeholder)
ca732855 827 HvPLACEHOLDERS(hv)++;
b2c64049
NC
828 if (masked_flags & HVhek_ENABLEHVKFLAGS)
829 HvHASKFLAGS_on(hv);
830
0298d7b9
NC
831 {
832 const HE *counter = HeNEXT(entry);
833
4c7185a0 834 xhv->xhv_keys++; /* HvTOTALKEYS(hv)++ */
0298d7b9
NC
835 if (!counter) { /* initial entry? */
836 xhv->xhv_fill++; /* HvFILL(hv)++ */
837 } else if (xhv->xhv_keys > (IV)xhv->xhv_max) {
838 hsplit(hv);
839 } else if(!HvREHASH(hv)) {
840 U32 n_links = 1;
841
842 while ((counter = HeNEXT(counter)))
843 n_links++;
844
845 if (n_links > HV_MAX_LENGTH_BEFORE_SPLIT) {
846 /* Use only the old HvKEYS(hv) > HvMAX(hv) condition to limit
847 bucket splits on a rehashed hash, as we're not going to
848 split it again, and if someone is lucky (evil) enough to
849 get all the keys in one list they could exhaust our memory
850 as we repeatedly double the number of buckets on every
851 entry. Linear search feels a less worse thing to do. */
852 hsplit(hv);
853 }
854 }
fde52b5c 855 }
b2c64049
NC
856
857 return entry;
fde52b5c
PP
858}
859
864dbfa3 860STATIC void
b0e6ae5b 861S_hv_magic_check(HV *hv, bool *needs_copy, bool *needs_store)
d0066dc7 862{
a3b680e6 863 const MAGIC *mg = SvMAGIC(hv);
d0066dc7
OT
864 *needs_copy = FALSE;
865 *needs_store = TRUE;
866 while (mg) {
867 if (isUPPER(mg->mg_type)) {
868 *needs_copy = TRUE;
d60c5a05 869 if (mg->mg_type == PERL_MAGIC_tied) {
d0066dc7 870 *needs_store = FALSE;
4ab2a30b 871 return; /* We've set all there is to set. */
d0066dc7
OT
872 }
873 }
874 mg = mg->mg_moremagic;
875 }
876}
877
954c1994 878/*
a3bcc51e
TP
879=for apidoc hv_scalar
880
881Evaluates the hash in scalar context and returns the result. Handles magic when the hash is tied.
882
883=cut
884*/
885
886SV *
887Perl_hv_scalar(pTHX_ HV *hv)
888{
a3bcc51e 889 SV *sv;
823a54a3
AL
890
891 if (SvRMAGICAL(hv)) {
892 MAGIC * const mg = mg_find((SV*)hv, PERL_MAGIC_tied);
893 if (mg)
894 return magic_scalarpack(hv, mg);
895 }
a3bcc51e
TP
896
897 sv = sv_newmortal();
898 if (HvFILL((HV*)hv))
899 Perl_sv_setpvf(aTHX_ sv, "%ld/%ld",
900 (long)HvFILL(hv), (long)HvMAX(hv) + 1);
901 else
902 sv_setiv(sv, 0);
903
904 return sv;
905}
906
907/*
954c1994
GS
908=for apidoc hv_delete
909
910Deletes a key/value pair in the hash. The value SV is removed from the
1c846c1f 911hash and returned to the caller. The C<klen> is the length of the key.
954c1994
GS
912The C<flags> value will normally be zero; if set to G_DISCARD then NULL
913will be returned.
914
915=cut
916*/
917
79072805 918SV *
cd6d36ac 919Perl_hv_delete(pTHX_ HV *hv, const char *key, I32 klen_i32, I32 flags)
79072805 920{
cd6d36ac 921 STRLEN klen;
6136c704 922 int k_flags;
cd6d36ac
NC
923
924 if (klen_i32 < 0) {
925 klen = -klen_i32;
6136c704 926 k_flags = HVhek_UTF8;
cd6d36ac
NC
927 } else {
928 klen = klen_i32;
6136c704 929 k_flags = 0;
cd6d36ac
NC
930 }
931 return hv_delete_common(hv, NULL, key, klen, k_flags, flags, 0);
fde52b5c
PP
932}
933
954c1994
GS
934/*
935=for apidoc hv_delete_ent
936
937Deletes a key/value pair in the hash. The value SV is removed from the
938hash and returned to the caller. The C<flags> value will normally be zero;
939if set to G_DISCARD then NULL will be returned. C<hash> can be a valid
940precomputed hash value, or 0 to ask for it to be computed.
941
942=cut
943*/
944
fabdb6c0 945/* XXX This looks like an ideal candidate to inline */
fde52b5c 946SV *
864dbfa3 947Perl_hv_delete_ent(pTHX_ HV *hv, SV *keysv, I32 flags, U32 hash)
fde52b5c 948{
cd6d36ac 949 return hv_delete_common(hv, keysv, NULL, 0, 0, flags, hash);
f1317c8d
NC
950}
951
8f8d40ab 952STATIC SV *
cd6d36ac
NC
953S_hv_delete_common(pTHX_ HV *hv, SV *keysv, const char *key, STRLEN klen,
954 int k_flags, I32 d_flags, U32 hash)
f1317c8d 955{
27da23d5 956 dVAR;
cbec9347 957 register XPVHV* xhv;
fde52b5c
PP
958 register HE *entry;
959 register HE **oentry;
9e720f71 960 HE *const *first_entry;
da58a35d 961 bool is_utf8;
7a9669ca 962 int masked_flags;
1c846c1f 963
fde52b5c 964 if (!hv)
a0714e2c 965 return NULL;
f1317c8d
NC
966
967 if (keysv) {
e593d2fe
AE
968 if (k_flags & HVhek_FREEKEY)
969 Safefree(key);
5c144d81 970 key = SvPV_const(keysv, klen);
cd6d36ac 971 k_flags = 0;
f1317c8d
NC
972 is_utf8 = (SvUTF8(keysv) != 0);
973 } else {
cd6d36ac 974 is_utf8 = ((k_flags & HVhek_UTF8) ? TRUE : FALSE);
f1317c8d 975 }
f1317c8d 976
fde52b5c 977 if (SvRMAGICAL(hv)) {
0a0bb7c7
OT
978 bool needs_copy;
979 bool needs_store;
980 hv_magic_check (hv, &needs_copy, &needs_store);
981
f1317c8d 982 if (needs_copy) {
6136c704 983 SV *sv;
7a9669ca
NC
984 entry = hv_fetch_common(hv, keysv, key, klen,
985 k_flags & ~HVhek_FREEKEY, HV_FETCH_LVALUE,
a0714e2c 986 NULL, hash);
7a9669ca 987 sv = entry ? HeVAL(entry) : NULL;
f1317c8d
NC
988 if (sv) {
989 if (SvMAGICAL(sv)) {
990 mg_clear(sv);
991 }
992 if (!needs_store) {
993 if (mg_find(sv, PERL_MAGIC_tiedelem)) {
994 /* No longer an element */
995 sv_unmagic(sv, PERL_MAGIC_tiedelem);
996 return sv;
997 }
a0714e2c 998 return NULL; /* element cannot be deleted */
f1317c8d 999 }
902173a3 1000#ifdef ENV_IS_CASELESS
8167a60a
NC
1001 else if (mg_find((SV*)hv, PERL_MAGIC_env)) {
1002 /* XXX This code isn't UTF8 clean. */
1003 keysv = sv_2mortal(newSVpvn(key,klen));
1004 if (k_flags & HVhek_FREEKEY) {
1005 Safefree(key);
1006 }
1007 key = strupr(SvPVX(keysv));
1008 is_utf8 = 0;
1009 k_flags = 0;
1010 hash = 0;
7f66fda2 1011 }
510ac311 1012#endif
2fd1c6b8 1013 }
2fd1c6b8 1014 }
fde52b5c 1015 }
cbec9347 1016 xhv = (XPVHV*)SvANY(hv);
7b2c381c 1017 if (!HvARRAY(hv))
a0714e2c 1018 return NULL;
fde52b5c 1019
19692e8d 1020 if (is_utf8) {
c445ea15 1021 const char * const keysave = key;
b464bac0 1022 key = (char*)bytes_from_utf8((U8*)key, &klen, &is_utf8);
cd6d36ac 1023
19692e8d 1024 if (is_utf8)
cd6d36ac
NC
1025 k_flags |= HVhek_UTF8;
1026 else
1027 k_flags &= ~HVhek_UTF8;
7f66fda2
NC
1028 if (key != keysave) {
1029 if (k_flags & HVhek_FREEKEY) {
1030 /* This shouldn't happen if our caller does what we expect,
1031 but strictly the API allows it. */
1032 Safefree(keysave);
1033 }
1034 k_flags |= HVhek_WASUTF8 | HVhek_FREEKEY;
1035 }
cd6d36ac 1036 HvHASKFLAGS_on((SV*)hv);
19692e8d 1037 }
f9a63242 1038
4b5190b5
NC
1039 if (HvREHASH(hv)) {
1040 PERL_HASH_INTERNAL(hash, key, klen);
1041 } else if (!hash) {
7a9669ca 1042 if (keysv && (SvIsCOW_shared_hash(keysv))) {
c158a4fd 1043 hash = SvSHARED_HASH(keysv);
7a9669ca
NC
1044 } else {
1045 PERL_HASH(hash, key, klen);
1046 }
4b5190b5 1047 }
fde52b5c 1048
7a9669ca
NC
1049 masked_flags = (k_flags & HVhek_MASK);
1050
9e720f71 1051 first_entry = oentry = &(HvARRAY(hv))[hash & (I32) HvMAX(hv)];
fde52b5c 1052 entry = *oentry;
9e720f71 1053 for (; entry; oentry = &HeNEXT(entry), entry = *oentry) {
6136c704 1054 SV *sv;
fde52b5c
PP
1055 if (HeHASH(entry) != hash) /* strings can't be equal */
1056 continue;
eb160463 1057 if (HeKLEN(entry) != (I32)klen)
fde52b5c 1058 continue;
1c846c1f 1059 if (HeKEY(entry) != key && memNE(HeKEY(entry),key,klen)) /* is this it? */
fde52b5c 1060 continue;
7a9669ca 1061 if ((HeKFLAGS(entry) ^ masked_flags) & HVhek_UTF8)
c3654f1a 1062 continue;
8aacddc1 1063
5d2b1485
NC
1064 if (hv == PL_strtab) {
1065 if (k_flags & HVhek_FREEKEY)
1066 Safefree(key);
1067 Perl_croak(aTHX_ S_strtab_error, "delete");
1068 }
1069
8aacddc1 1070 /* if placeholder is here, it's already been deleted.... */
6136c704
AL
1071 if (HeVAL(entry) == &PL_sv_placeholder) {
1072 if (k_flags & HVhek_FREEKEY)
1073 Safefree(key);
1074 return NULL;
8aacddc1 1075 }
6136c704 1076 if (SvREADONLY(hv) && HeVAL(entry) && SvREADONLY(HeVAL(entry))) {
d4c19fe8 1077 hv_notallowed(k_flags, key, klen,
c8cd6465
NC
1078 "Attempt to delete readonly key '%"SVf"' from"
1079 " a restricted hash");
8aacddc1 1080 }
b84d0860
NC
1081 if (k_flags & HVhek_FREEKEY)
1082 Safefree(key);
8aacddc1 1083
cd6d36ac 1084 if (d_flags & G_DISCARD)
a0714e2c 1085 sv = NULL;
94f7643d 1086 else {
79d01fbf 1087 sv = sv_2mortal(HeVAL(entry));
7996736c 1088 HeVAL(entry) = &PL_sv_placeholder;
94f7643d 1089 }
8aacddc1
NIS
1090
1091 /*
1092 * If a restricted hash, rather than really deleting the entry, put
1093 * a placeholder there. This marks the key as being "approved", so
1094 * we can still access via not-really-existing key without raising
1095 * an error.
1096 */
1097 if (SvREADONLY(hv)) {
754604c4 1098 SvREFCNT_dec(HeVAL(entry));
7996736c 1099 HeVAL(entry) = &PL_sv_placeholder;
8aacddc1
NIS
1100 /* We'll be saving this slot, so the number of allocated keys
1101 * doesn't go down, but the number placeholders goes up */
ca732855 1102 HvPLACEHOLDERS(hv)++;
8aacddc1 1103 } else {
a26e96df 1104 *oentry = HeNEXT(entry);
9e720f71 1105 if(!*first_entry) {
a26e96df 1106 xhv->xhv_fill--; /* HvFILL(hv)-- */
9e720f71 1107 }
b79f7545 1108 if (SvOOK(hv) && entry == HvAUX(hv)->xhv_eiter /* HvEITER(hv) */)
8aacddc1
NIS
1109 HvLAZYDEL_on(hv);
1110 else
1111 hv_free_ent(hv, entry);
4c7185a0 1112 xhv->xhv_keys--; /* HvTOTALKEYS(hv)-- */
574c8022 1113 if (xhv->xhv_keys == 0)
19692e8d 1114 HvHASKFLAGS_off(hv);
8aacddc1 1115 }
79072805
LW
1116 return sv;
1117 }
8aacddc1 1118 if (SvREADONLY(hv)) {
d4c19fe8 1119 hv_notallowed(k_flags, key, klen,
c8cd6465
NC
1120 "Attempt to delete disallowed key '%"SVf"' from"
1121 " a restricted hash");
8aacddc1
NIS
1122 }
1123
19692e8d 1124 if (k_flags & HVhek_FREEKEY)
f9a63242 1125 Safefree(key);
a0714e2c 1126 return NULL;
79072805
LW
1127}
1128
76e3520e 1129STATIC void
cea2e8a9 1130S_hsplit(pTHX_ HV *hv)
79072805 1131{
97aff369 1132 dVAR;
cbec9347 1133 register XPVHV* xhv = (XPVHV*)SvANY(hv);
a3b680e6 1134 const I32 oldsize = (I32) xhv->xhv_max+1; /* HvMAX(hv)+1 (sick) */
79072805
LW
1135 register I32 newsize = oldsize * 2;
1136 register I32 i;
7b2c381c 1137 char *a = (char*) HvARRAY(hv);
72311751 1138 register HE **aep;
79072805 1139 register HE **oentry;
4b5190b5
NC
1140 int longest_chain = 0;
1141 int was_shared;
79072805 1142
18026298
NC
1143 /*PerlIO_printf(PerlIO_stderr(), "hsplit called for %p which had %d\n",
1144 hv, (int) oldsize);*/
1145
5d88ecd7 1146 if (HvPLACEHOLDERS_get(hv) && !SvREADONLY(hv)) {
18026298
NC
1147 /* Can make this clear any placeholders first for non-restricted hashes,
1148 even though Storable rebuilds restricted hashes by putting in all the
1149 placeholders (first) before turning on the readonly flag, because
1150 Storable always pre-splits the hash. */
1151 hv_clear_placeholders(hv);
1152 }
1153
3280af22 1154 PL_nomemok = TRUE;
8d6dde3e 1155#if defined(STRANGE_MALLOC) || defined(MYMALLOC)
b79f7545
NC
1156 Renew(a, PERL_HV_ARRAY_ALLOC_BYTES(newsize)
1157 + (SvOOK(hv) ? sizeof(struct xpvhv_aux) : 0), char);
422a93e5 1158 if (!a) {
4a33f861 1159 PL_nomemok = FALSE;
422a93e5
GA
1160 return;
1161 }
b79f7545 1162 if (SvOOK(hv)) {
7a9b70e9 1163 Copy(&a[oldsize * sizeof(HE*)], &a[newsize * sizeof(HE*)], 1, struct xpvhv_aux);
b79f7545 1164 }
4633a7c4 1165#else
a02a5408 1166 Newx(a, PERL_HV_ARRAY_ALLOC_BYTES(newsize)
b79f7545 1167 + (SvOOK(hv) ? sizeof(struct xpvhv_aux) : 0), char);
422a93e5 1168 if (!a) {
3280af22 1169 PL_nomemok = FALSE;
422a93e5
GA
1170 return;
1171 }
7b2c381c 1172 Copy(HvARRAY(hv), a, oldsize * sizeof(HE*), char);
b79f7545
NC
1173 if (SvOOK(hv)) {
1174 Copy(HvAUX(hv), &a[newsize * sizeof(HE*)], 1, struct xpvhv_aux);
1175 }
fba3b22e 1176 if (oldsize >= 64) {
7b2c381c 1177 offer_nice_chunk(HvARRAY(hv),
b79f7545
NC
1178 PERL_HV_ARRAY_ALLOC_BYTES(oldsize)
1179 + (SvOOK(hv) ? sizeof(struct xpvhv_aux) : 0));
4633a7c4
LW
1180 }
1181 else
7b2c381c 1182 Safefree(HvARRAY(hv));
4633a7c4
LW
1183#endif
1184
3280af22 1185 PL_nomemok = FALSE;
72311751 1186 Zero(&a[oldsize * sizeof(HE*)], (newsize-oldsize) * sizeof(HE*), char); /* zero 2nd half*/
cbec9347 1187 xhv->xhv_max = --newsize; /* HvMAX(hv) = --newsize */
7b2c381c 1188 HvARRAY(hv) = (HE**) a;
72311751 1189 aep = (HE**)a;
79072805 1190
72311751 1191 for (i=0; i<oldsize; i++,aep++) {
4b5190b5
NC
1192 int left_length = 0;
1193 int right_length = 0;
a3b680e6
AL
1194 register HE *entry;
1195 register HE **bep;
4b5190b5 1196
72311751 1197 if (!*aep) /* non-existent */
79072805 1198 continue;
72311751
GS
1199 bep = aep+oldsize;
1200 for (oentry = aep, entry = *aep; entry; entry = *oentry) {
eb160463 1201 if ((HeHASH(entry) & newsize) != (U32)i) {
fde52b5c 1202 *oentry = HeNEXT(entry);
72311751
GS
1203 HeNEXT(entry) = *bep;
1204 if (!*bep)
cbec9347 1205 xhv->xhv_fill++; /* HvFILL(hv)++ */
72311751 1206 *bep = entry;
4b5190b5 1207 right_length++;
79072805
LW
1208 continue;
1209 }
4b5190b5 1210 else {
fde52b5c 1211 oentry = &HeNEXT(entry);
4b5190b5
NC
1212 left_length++;
1213 }
79072805 1214 }
72311751 1215 if (!*aep) /* everything moved */
cbec9347 1216 xhv->xhv_fill--; /* HvFILL(hv)-- */
4b5190b5
NC
1217 /* I think we don't actually need to keep track of the longest length,
1218 merely flag if anything is too long. But for the moment while
1219 developing this code I'll track it. */
1220 if (left_length > longest_chain)
1221 longest_chain = left_length;
1222 if (right_length > longest_chain)
1223 longest_chain = right_length;
1224 }
1225
1226
1227 /* Pick your policy for "hashing isn't working" here: */
fdcd69b6 1228 if (longest_chain <= HV_MAX_LENGTH_BEFORE_SPLIT /* split worked? */
4b5190b5
NC
1229 || HvREHASH(hv)) {
1230 return;
79072805 1231 }
4b5190b5
NC
1232
1233 if (hv == PL_strtab) {
1234 /* Urg. Someone is doing something nasty to the string table.
1235 Can't win. */
1236 return;
1237 }
1238
1239 /* Awooga. Awooga. Pathological data. */
fdcd69b6 1240 /*PerlIO_printf(PerlIO_stderr(), "%p %d of %d with %d/%d buckets\n", hv,
4b5190b5
NC
1241 longest_chain, HvTOTALKEYS(hv), HvFILL(hv), 1+HvMAX(hv));*/
1242
1243 ++newsize;
a02a5408 1244 Newxz(a, PERL_HV_ARRAY_ALLOC_BYTES(newsize)
b79f7545
NC
1245 + (SvOOK(hv) ? sizeof(struct xpvhv_aux) : 0), char);
1246 if (SvOOK(hv)) {
1247 Copy(HvAUX(hv), &a[newsize * sizeof(HE*)], 1, struct xpvhv_aux);
1248 }
1249
4b5190b5
NC
1250 was_shared = HvSHAREKEYS(hv);
1251
1252 xhv->xhv_fill = 0;
1253 HvSHAREKEYS_off(hv);
1254 HvREHASH_on(hv);
1255
7b2c381c 1256 aep = HvARRAY(hv);
4b5190b5
NC
1257
1258 for (i=0; i<newsize; i++,aep++) {
a3b680e6 1259 register HE *entry = *aep;
4b5190b5
NC
1260 while (entry) {
1261 /* We're going to trash this HE's next pointer when we chain it
1262 into the new hash below, so store where we go next. */
9d4ba2ae 1263 HE * const next = HeNEXT(entry);
4b5190b5 1264 UV hash;
a3b680e6 1265 HE **bep;
4b5190b5
NC
1266
1267 /* Rehash it */
1268 PERL_HASH_INTERNAL(hash, HeKEY(entry), HeKLEN(entry));
1269
1270 if (was_shared) {
1271 /* Unshare it. */
aec46f14 1272 HEK * const new_hek
4b5190b5
NC
1273 = save_hek_flags(HeKEY(entry), HeKLEN(entry),
1274 hash, HeKFLAGS(entry));
1275 unshare_hek (HeKEY_hek(entry));
1276 HeKEY_hek(entry) = new_hek;
1277 } else {
1278 /* Not shared, so simply write the new hash in. */
1279 HeHASH(entry) = hash;
1280 }
1281 /*PerlIO_printf(PerlIO_stderr(), "%d ", HeKFLAGS(entry));*/
1282 HEK_REHASH_on(HeKEY_hek(entry));
1283 /*PerlIO_printf(PerlIO_stderr(), "%d\n", HeKFLAGS(entry));*/
1284
1285 /* Copy oentry to the correct new chain. */
1286 bep = ((HE**)a) + (hash & (I32) xhv->xhv_max);
1287 if (!*bep)
1288 xhv->xhv_fill++; /* HvFILL(hv)++ */
1289 HeNEXT(entry) = *bep;
1290 *bep = entry;
1291
1292 entry = next;
1293 }
1294 }
7b2c381c
NC
1295 Safefree (HvARRAY(hv));
1296 HvARRAY(hv) = (HE **)a;
79072805
LW
1297}
1298
72940dca 1299void
864dbfa3 1300Perl_hv_ksplit(pTHX_ HV *hv, IV newmax)
72940dca 1301{
97aff369 1302 dVAR;
cbec9347 1303 register XPVHV* xhv = (XPVHV*)SvANY(hv);
a3b680e6 1304 const I32 oldsize = (I32) xhv->xhv_max+1; /* HvMAX(hv)+1 (sick) */
72940dca
PP
1305 register I32 newsize;
1306 register I32 i;
72311751
GS
1307 register char *a;
1308 register HE **aep;
72940dca
PP
1309 register HE *entry;
1310 register HE **oentry;
1311
1312 newsize = (I32) newmax; /* possible truncation here */
1313 if (newsize != newmax || newmax <= oldsize)
1314 return;
1315 while ((newsize & (1 + ~newsize)) != newsize) {
1316 newsize &= ~(newsize & (1 + ~newsize)); /* get proper power of 2 */
1317 }
1318 if (newsize < newmax)
1319 newsize *= 2;
1320 if (newsize < newmax)
1321 return; /* overflow detection */
1322
7b2c381c 1323 a = (char *) HvARRAY(hv);
72940dca 1324 if (a) {
3280af22 1325 PL_nomemok = TRUE;
8d6dde3e 1326#if defined(STRANGE_MALLOC) || defined(MYMALLOC)
b79f7545
NC
1327 Renew(a, PERL_HV_ARRAY_ALLOC_BYTES(newsize)
1328 + (SvOOK(hv) ? sizeof(struct xpvhv_aux) : 0), char);
8aacddc1 1329 if (!a) {
4a33f861 1330 PL_nomemok = FALSE;
422a93e5
GA
1331 return;
1332 }
b79f7545 1333 if (SvOOK(hv)) {
7a9b70e9 1334 Copy(&a[oldsize * sizeof(HE*)], &a[newsize * sizeof(HE*)], 1, struct xpvhv_aux);
b79f7545 1335 }
72940dca 1336#else
a02a5408 1337 Newx(a, PERL_HV_ARRAY_ALLOC_BYTES(newsize)
b79f7545 1338 + (SvOOK(hv) ? sizeof(struct xpvhv_aux) : 0), char);
8aacddc1 1339 if (!a) {
3280af22 1340 PL_nomemok = FALSE;
422a93e5
GA
1341 return;
1342 }
7b2c381c 1343 Copy(HvARRAY(hv), a, oldsize * sizeof(HE*), char);
b79f7545
NC
1344 if (SvOOK(hv)) {
1345 Copy(HvAUX(hv), &a[newsize * sizeof(HE*)], 1, struct xpvhv_aux);
1346 }
fba3b22e 1347 if (oldsize >= 64) {
7b2c381c 1348 offer_nice_chunk(HvARRAY(hv),
b79f7545
NC
1349 PERL_HV_ARRAY_ALLOC_BYTES(oldsize)
1350 + (SvOOK(hv) ? sizeof(struct xpvhv_aux) : 0));
72940dca
PP
1351 }
1352 else
7b2c381c 1353 Safefree(HvARRAY(hv));
72940dca 1354#endif
3280af22 1355 PL_nomemok = FALSE;
72311751 1356 Zero(&a[oldsize * sizeof(HE*)], (newsize-oldsize) * sizeof(HE*), char); /* zero 2nd half*/
72940dca
PP
1357 }
1358 else {
a02a5408 1359 Newxz(a, PERL_HV_ARRAY_ALLOC_BYTES(newsize), char);
72940dca 1360 }
cbec9347 1361 xhv->xhv_max = --newsize; /* HvMAX(hv) = --newsize */
7b2c381c 1362 HvARRAY(hv) = (HE **) a;
cbec9347 1363 if (!xhv->xhv_fill /* !HvFILL(hv) */) /* skip rest if no entries */
72940dca
PP
1364 return;
1365
72311751
GS
1366 aep = (HE**)a;
1367 for (i=0; i<oldsize; i++,aep++) {
1368 if (!*aep) /* non-existent */
72940dca 1369 continue;
72311751 1370 for (oentry = aep, entry = *aep; entry; entry = *oentry) {
6136c704
AL
1371 register I32 j = (HeHASH(entry) & newsize);
1372
1373 if (j != i) {
72940dca
PP
1374 j -= i;
1375 *oentry = HeNEXT(entry);
72311751 1376 if (!(HeNEXT(entry) = aep[j]))
cbec9347 1377 xhv->xhv_fill++; /* HvFILL(hv)++ */
72311751 1378 aep[j] = entry;
72940dca
PP
1379 continue;
1380 }
1381 else
1382 oentry = &HeNEXT(entry);
1383 }
72311751 1384 if (!*aep) /* everything moved */
cbec9347 1385 xhv->xhv_fill--; /* HvFILL(hv)-- */
72940dca
PP
1386 }
1387}
1388
954c1994
GS
1389/*
1390=for apidoc newHV
1391
1392Creates a new HV. The reference count is set to 1.
1393
1394=cut
1395*/
1396
79072805 1397HV *
864dbfa3 1398Perl_newHV(pTHX)
79072805 1399{
cbec9347 1400 register XPVHV* xhv;
561b68a9 1401 HV * const hv = (HV*)newSV(0);
79072805 1402
a0d0e21e 1403 sv_upgrade((SV *)hv, SVt_PVHV);
cbec9347 1404 xhv = (XPVHV*)SvANY(hv);
79072805
LW
1405 SvPOK_off(hv);
1406 SvNOK_off(hv);
1c846c1f 1407#ifndef NODEFAULT_SHAREKEYS
fde52b5c 1408 HvSHAREKEYS_on(hv); /* key-sharing on by default */
1c846c1f 1409#endif
4b5190b5 1410
cbec9347
JH
1411 xhv->xhv_max = 7; /* HvMAX(hv) = 7 (start with 8 buckets) */
1412 xhv->xhv_fill = 0; /* HvFILL(hv) = 0 */
79072805
LW
1413 return hv;
1414}
1415
b3ac6de7 1416HV *
864dbfa3 1417Perl_newHVhv(pTHX_ HV *ohv)
b3ac6de7 1418{
9d4ba2ae 1419 HV * const hv = newHV();
4beac62f 1420 STRLEN hv_max, hv_fill;
4beac62f
AMS
1421
1422 if (!ohv || (hv_fill = HvFILL(ohv)) == 0)
1423 return hv;
4beac62f 1424 hv_max = HvMAX(ohv);
b3ac6de7 1425
b56ba0bf
AMS
1426 if (!SvMAGICAL((SV *)ohv)) {
1427 /* It's an ordinary hash, so copy it fast. AMS 20010804 */
eb160463 1428 STRLEN i;
a3b680e6 1429 const bool shared = !!HvSHAREKEYS(ohv);
aec46f14 1430 HE **ents, ** const oents = (HE **)HvARRAY(ohv);
ff875642 1431 char *a;
a02a5408 1432 Newx(a, PERL_HV_ARRAY_ALLOC_BYTES(hv_max+1), char);
ff875642 1433 ents = (HE**)a;
b56ba0bf
AMS
1434
1435 /* In each bucket... */
1436 for (i = 0; i <= hv_max; i++) {
6136c704 1437 HE *prev = NULL;
aec46f14 1438 HE *oent = oents[i];
b56ba0bf
AMS
1439
1440 if (!oent) {
1441 ents[i] = NULL;
1442 continue;
1443 }
1444
1445 /* Copy the linked list of entries. */
aec46f14 1446 for (; oent; oent = HeNEXT(oent)) {
a3b680e6
AL
1447 const U32 hash = HeHASH(oent);
1448 const char * const key = HeKEY(oent);
1449 const STRLEN len = HeKLEN(oent);
1450 const int flags = HeKFLAGS(oent);
6136c704 1451 HE * const ent = new_HE();
b56ba0bf 1452
45dea987 1453 HeVAL(ent) = newSVsv(HeVAL(oent));
19692e8d 1454 HeKEY_hek(ent)
6e838c70 1455 = shared ? share_hek_flags(key, len, hash, flags)
19692e8d 1456 : save_hek_flags(key, len, hash, flags);
b56ba0bf
AMS
1457 if (prev)
1458 HeNEXT(prev) = ent;
1459 else
1460 ents[i] = ent;
1461 prev = ent;
1462 HeNEXT(ent) = NULL;
1463 }
1464 }
1465
1466 HvMAX(hv) = hv_max;
1467 HvFILL(hv) = hv_fill;
8aacddc1 1468 HvTOTALKEYS(hv) = HvTOTALKEYS(ohv);
b56ba0bf 1469 HvARRAY(hv) = ents;
aec46f14 1470 } /* not magical */
b56ba0bf
AMS
1471 else {
1472 /* Iterate over ohv, copying keys and values one at a time. */
b3ac6de7 1473 HE *entry;
bfcb3514
NC
1474 const I32 riter = HvRITER_get(ohv);
1475 HE * const eiter = HvEITER_get(ohv);
b56ba0bf
AMS
1476
1477 /* Can we use fewer buckets? (hv_max is always 2^n-1) */
1478 while (hv_max && hv_max + 1 >= hv_fill * 2)
1479 hv_max = hv_max / 2;
1480 HvMAX(hv) = hv_max;
1481
4a76a316 1482 hv_iterinit(ohv);
e16e2ff8 1483 while ((entry = hv_iternext_flags(ohv, 0))) {
19692e8d
NC
1484 hv_store_flags(hv, HeKEY(entry), HeKLEN(entry),
1485 newSVsv(HeVAL(entry)), HeHASH(entry),
1486 HeKFLAGS(entry));
b3ac6de7 1487 }
bfcb3514
NC
1488 HvRITER_set(ohv, riter);
1489 HvEITER_set(ohv, eiter);
b3ac6de7 1490 }
1c846c1f 1491
b3ac6de7
IZ
1492 return hv;
1493}
1494
5b9c0671
NC
1495/* A rather specialised version of newHVhv for copying %^H, ensuring all the
1496 magic stays on it. */
1497HV *
1498Perl_hv_copy_hints_hv(pTHX_ HV *const ohv)
1499{
1500 HV * const hv = newHV();
1501 STRLEN hv_fill;
1502
1503 if (ohv && (hv_fill = HvFILL(ohv))) {
1504 STRLEN hv_max = HvMAX(ohv);
1505 HE *entry;
1506 const I32 riter = HvRITER_get(ohv);
1507 HE * const eiter = HvEITER_get(ohv);
1508
1509 while (hv_max && hv_max + 1 >= hv_fill * 2)
1510 hv_max = hv_max / 2;
1511 HvMAX(hv) = hv_max;
1512
1513 hv_iterinit(ohv);
1514 while ((entry = hv_iternext_flags(ohv, 0))) {
1515 SV *const sv = newSVsv(HeVAL(entry));
1516 sv_magic(sv, NULL, PERL_MAGIC_hintselem,
1517 (char *)newSVhek (HeKEY_hek(entry)), HEf_SVKEY);
1518 hv_store_flags(hv, HeKEY(entry), HeKLEN(entry),
1519 sv, HeHASH(entry), HeKFLAGS(entry));
1520 }
1521 HvRITER_set(ohv, riter);
1522 HvEITER_set(ohv, eiter);
1523 }
1524 hv_magic(hv, NULL, PERL_MAGIC_hints);
1525 return hv;
1526}
1527
79072805 1528void
864dbfa3 1529Perl_hv_free_ent(pTHX_ HV *hv, register HE *entry)
79072805 1530{
97aff369 1531 dVAR;
16bdeea2
GS
1532 SV *val;
1533
68dc0745 1534 if (!entry)
79072805 1535 return;
16bdeea2 1536 val = HeVAL(entry);
bfcb3514 1537 if (val && isGV(val) && GvCVu(val) && HvNAME_get(hv))
3280af22 1538 PL_sub_generation++; /* may be deletion of method from stash */
16bdeea2 1539 SvREFCNT_dec(val);
68dc0745
PP
1540 if (HeKLEN(entry) == HEf_SVKEY) {
1541 SvREFCNT_dec(HeKEY_sv(entry));
8aacddc1 1542 Safefree(HeKEY_hek(entry));
44a8e56a
PP
1543 }
1544 else if (HvSHAREKEYS(hv))
68dc0745 1545 unshare_hek(HeKEY_hek(entry));
fde52b5c 1546 else
68dc0745 1547 Safefree(HeKEY_hek(entry));
d33b2eba 1548 del_HE(entry);
79072805
LW
1549}
1550
1551void
864dbfa3 1552Perl_hv_delayfree_ent(pTHX_ HV *hv, register HE *entry)
79072805 1553{
97aff369 1554 dVAR;
68dc0745 1555 if (!entry)
79072805 1556 return;
bc4947fc
NC
1557 /* SvREFCNT_inc to counter the SvREFCNT_dec in hv_free_ent */
1558 sv_2mortal(SvREFCNT_inc(HeVAL(entry))); /* free between statements */
68dc0745 1559 if (HeKLEN(entry) == HEf_SVKEY) {
bc4947fc 1560 sv_2mortal(SvREFCNT_inc(HeKEY_sv(entry)));
44a8e56a 1561 }
bc4947fc 1562 hv_free_ent(hv, entry);
79072805
LW
1563}
1564
954c1994
GS
1565/*
1566=for apidoc hv_clear
1567
1568Clears a hash, making it empty.
1569
1570=cut
1571*/
1572
79072805 1573void
864dbfa3 1574Perl_hv_clear(pTHX_ HV *hv)
79072805 1575{
27da23d5 1576 dVAR;
cbec9347 1577 register XPVHV* xhv;
79072805
LW
1578 if (!hv)
1579 return;
49293501 1580
ecae49c0
NC
1581 DEBUG_A(Perl_hv_assert(aTHX_ hv));
1582
34c3c4e3
DM
1583 xhv = (XPVHV*)SvANY(hv);
1584
7b2c381c 1585 if (SvREADONLY(hv) && HvARRAY(hv) != NULL) {
34c3c4e3 1586 /* restricted hash: convert all keys to placeholders */
b464bac0
AL
1587 STRLEN i;
1588 for (i = 0; i <= xhv->xhv_max; i++) {
7b2c381c 1589 HE *entry = (HvARRAY(hv))[i];
3a676441
JH
1590 for (; entry; entry = HeNEXT(entry)) {
1591 /* not already placeholder */
7996736c 1592 if (HeVAL(entry) != &PL_sv_placeholder) {
3a676441 1593 if (HeVAL(entry) && SvREADONLY(HeVAL(entry))) {
6136c704 1594 SV* const keysv = hv_iterkeysv(entry);
3a676441 1595 Perl_croak(aTHX_
95b63a38
JH
1596 "Attempt to delete readonly key '%"SVf"' from a restricted hash",
1597 (void*)keysv);
3a676441
JH
1598 }
1599 SvREFCNT_dec(HeVAL(entry));
7996736c 1600 HeVAL(entry) = &PL_sv_placeholder;
ca732855 1601 HvPLACEHOLDERS(hv)++;
3a676441 1602 }
34c3c4e3
DM
1603 }
1604 }
df8c6964 1605 goto reset;
49293501
MS
1606 }
1607
463ee0b2 1608 hfreeentries(hv);
ca732855 1609 HvPLACEHOLDERS_set(hv, 0);
7b2c381c 1610 if (HvARRAY(hv))
41f62432 1611 Zero(HvARRAY(hv), xhv->xhv_max+1 /* HvMAX(hv)+1 */, HE*);
a0d0e21e
LW
1612
1613 if (SvRMAGICAL(hv))
1c846c1f 1614 mg_clear((SV*)hv);
574c8022 1615
19692e8d 1616 HvHASKFLAGS_off(hv);
bb443f97 1617 HvREHASH_off(hv);
df8c6964 1618 reset:
b79f7545 1619 if (SvOOK(hv)) {
bfcb3514
NC
1620 HvEITER_set(hv, NULL);
1621 }
79072805
LW
1622}
1623
3540d4ce
AB
1624/*
1625=for apidoc hv_clear_placeholders
1626
1627Clears any placeholders from a hash. If a restricted hash has any of its keys
1628marked as readonly and the key is subsequently deleted, the key is not actually
1629deleted but is marked by assigning it a value of &PL_sv_placeholder. This tags
1630it so it will be ignored by future operations such as iterating over the hash,
4cdaeff7 1631but will still allow the hash to have a value reassigned to the key at some
3540d4ce
AB
1632future point. This function clears any such placeholder keys from the hash.
1633See Hash::Util::lock_keys() for an example of its use.
1634
1635=cut
1636*/
1637
1638void
1639Perl_hv_clear_placeholders(pTHX_ HV *hv)
1640{
27da23d5 1641 dVAR;
b3ca2e83
NC
1642 const U32 items = (U32)HvPLACEHOLDERS_get(hv);
1643
1644 if (items)
1645 clear_placeholders(hv, items);
1646}
1647
1648static void
1649S_clear_placeholders(pTHX_ HV *hv, U32 items)
1650{
1651 dVAR;
b464bac0 1652 I32 i;
d3677389
NC
1653
1654 if (items == 0)
1655 return;
1656
b464bac0 1657 i = HvMAX(hv);
d3677389
NC
1658 do {
1659 /* Loop down the linked list heads */
6136c704 1660 bool first = TRUE;
d3677389 1661 HE **oentry = &(HvARRAY(hv))[i];
cf6db12b 1662 HE *entry;
d3677389 1663
cf6db12b 1664 while ((entry = *oentry)) {
d3677389
NC
1665 if (HeVAL(entry) == &PL_sv_placeholder) {
1666 *oentry = HeNEXT(entry);
1667 if (first && !*oentry)
1668 HvFILL(hv)--; /* This linked list is now empty. */
2e58978b 1669 if (entry == HvEITER_get(hv))
d3677389
NC
1670 HvLAZYDEL_on(hv);
1671 else
1672 hv_free_ent(hv, entry);
1673
1674 if (--items == 0) {
1675 /* Finished. */
5d88ecd7 1676 HvTOTALKEYS(hv) -= (IV)HvPLACEHOLDERS_get(hv);
d3677389
NC
1677 if (HvKEYS(hv) == 0)
1678 HvHASKFLAGS_off(hv);
5d88ecd7 1679 HvPLACEHOLDERS_set(hv, 0);
d3677389
NC
1680 return;
1681 }
213ce8b3
NC
1682 } else {
1683 oentry = &HeNEXT(entry);
6136c704 1684 first = FALSE;
d3677389
NC
1685 }
1686 }
1687 } while (--i >= 0);
1688 /* You can't get here, hence assertion should always fail. */
1689 assert (items == 0);
1690 assert (0);
3540d4ce
AB
1691}
1692
76e3520e 1693STATIC void
cea2e8a9 1694S_hfreeentries(pTHX_ HV *hv)
79072805 1695{
23976bdd
NC
1696 /* This is the array that we're going to restore */
1697 HE **orig_array;
1698 HEK *name;
1699 int attempts = 100;
3abe233e 1700
a0d0e21e 1701 if (!HvARRAY(hv))
79072805 1702 return;
a0d0e21e 1703
23976bdd
NC
1704 if (SvOOK(hv)) {
1705 /* If the hash is actually a symbol table with a name, look after the
1706 name. */
1707 struct xpvhv_aux *iter = HvAUX(hv);
1708
1709 name = iter->xhv_name;
1710 iter->xhv_name = NULL;
1711 } else {
1712 name = NULL;
1713 }
1714
1715 orig_array = HvARRAY(hv);
1716 /* orig_array remains unchanged throughout the loop. If after freeing all
1717 the entries it turns out that one of the little blighters has triggered
1718 an action that has caused HvARRAY to be re-allocated, then we set
1719 array to the new HvARRAY, and try again. */
1720
1721 while (1) {
1722 /* This is the one we're going to try to empty. First time round
1723 it's the original array. (Hopefully there will only be 1 time
1724 round) */
6136c704 1725 HE ** const array = HvARRAY(hv);
7440661e 1726 I32 i = HvMAX(hv);
23976bdd
NC
1727
1728 /* Because we have taken xhv_name out, the only allocated pointer
1729 in the aux structure that might exist is the backreference array.
1730 */
1731
1732 if (SvOOK(hv)) {
7440661e 1733 HE *entry;
23976bdd
NC
1734 struct xpvhv_aux *iter = HvAUX(hv);
1735 /* If there are weak references to this HV, we need to avoid
1736 freeing them up here. In particular we need to keep the AV
1737 visible as what we're deleting might well have weak references
1738 back to this HV, so the for loop below may well trigger
1739 the removal of backreferences from this array. */
1740
1741 if (iter->xhv_backreferences) {
1742 /* So donate them to regular backref magic to keep them safe.
1743 The sv_magic will increase the reference count of the AV,
1744 so we need to drop it first. */
5b285ea4 1745 SvREFCNT_dec(iter->xhv_backreferences);
23976bdd
NC
1746 if (AvFILLp(iter->xhv_backreferences) == -1) {
1747 /* Turns out that the array is empty. Just free it. */
1748 SvREFCNT_dec(iter->xhv_backreferences);
1b8791d1 1749
23976bdd
NC
1750 } else {
1751 sv_magic((SV*)hv, (SV*)iter->xhv_backreferences,
1752 PERL_MAGIC_backref, NULL, 0);
1753 }
1754 iter->xhv_backreferences = NULL;
5b285ea4 1755 }
86f55936 1756
23976bdd
NC
1757 entry = iter->xhv_eiter; /* HvEITER(hv) */
1758 if (entry && HvLAZYDEL(hv)) { /* was deleted earlier? */
1759 HvLAZYDEL_off(hv);
1760 hv_free_ent(hv, entry);
1761 }
1762 iter->xhv_riter = -1; /* HvRITER(hv) = -1 */
4608196e 1763 iter->xhv_eiter = NULL; /* HvEITER(hv) = NULL */
b79f7545 1764
23976bdd 1765 /* There are now no allocated pointers in the aux structure. */
2f86008e 1766
23976bdd
NC
1767 SvFLAGS(hv) &= ~SVf_OOK; /* Goodbye, aux structure. */
1768 /* What aux structure? */
a0d0e21e 1769 }
bfcb3514 1770
23976bdd
NC
1771 /* make everyone else think the array is empty, so that the destructors
1772 * called for freed entries can't recusively mess with us */
1773 HvARRAY(hv) = NULL;
1774 HvFILL(hv) = 0;
1775 ((XPVHV*) SvANY(hv))->xhv_keys = 0;
1776
7440661e
NC
1777
1778 do {
1779 /* Loop down the linked list heads */
1780 HE *entry = array[i];
1781
1782 while (entry) {
23976bdd
NC
1783 register HE * const oentry = entry;
1784 entry = HeNEXT(entry);
1785 hv_free_ent(hv, oentry);
1786 }
7440661e 1787 } while (--i >= 0);
b79f7545 1788
23976bdd
NC
1789 /* As there are no allocated pointers in the aux structure, it's now
1790 safe to free the array we just cleaned up, if it's not the one we're
1791 going to put back. */
1792 if (array != orig_array) {
1793 Safefree(array);
1794 }
b79f7545 1795
23976bdd
NC
1796 if (!HvARRAY(hv)) {
1797 /* Good. No-one added anything this time round. */
1798 break;
bfcb3514 1799 }
b79f7545 1800
23976bdd
NC
1801 if (SvOOK(hv)) {
1802 /* Someone attempted to iterate or set the hash name while we had
1803 the array set to 0. We'll catch backferences on the next time
1804 round the while loop. */
1805 assert(HvARRAY(hv));
1b8791d1 1806
23976bdd
NC
1807 if (HvAUX(hv)->xhv_name) {
1808 unshare_hek_or_pvn(HvAUX(hv)->xhv_name, 0, 0, 0);
1809 }
1810 }
1811
1812 if (--attempts == 0) {
1813 Perl_die(aTHX_ "panic: hfreeentries failed to free hash - something is repeatedly re-creating entries");
1814 }
6136c704 1815 }
23976bdd
NC
1816
1817 HvARRAY(hv) = orig_array;
1818
1819 /* If the hash was actually a symbol table, put the name back. */
1820 if (name) {
1821 /* We have restored the original array. If name is non-NULL, then
1822 the original array had an aux structure at the end. So this is
1823 valid: */
1824 SvFLAGS(hv) |= SVf_OOK;
1825 HvAUX(hv)->xhv_name = name;
1b8791d1 1826 }
79072805
LW
1827}
1828
954c1994
GS
1829/*
1830=for apidoc hv_undef
1831
1832Undefines the hash.
1833
1834=cut
1835*/
1836
79072805 1837void
864dbfa3 1838Perl_hv_undef(pTHX_ HV *hv)
79072805 1839{
97aff369 1840 dVAR;
cbec9347 1841 register XPVHV* xhv;
bfcb3514 1842 const char *name;
86f55936 1843
79072805
LW
1844 if (!hv)
1845 return;
ecae49c0 1846 DEBUG_A(Perl_hv_assert(aTHX_ hv));
cbec9347 1847 xhv = (XPVHV*)SvANY(hv);
463ee0b2 1848 hfreeentries(hv);
bfcb3514 1849 if ((name = HvNAME_get(hv))) {
7e8961ec 1850 if(PL_stashcache)
7423f6db 1851 hv_delete(PL_stashcache, name, HvNAMELEN_get(hv), G_DISCARD);
bd61b366 1852 hv_name_set(hv, NULL, 0, 0);
85e6fe83 1853 }
b79f7545
NC
1854 SvFLAGS(hv) &= ~SVf_OOK;
1855 Safefree(HvARRAY(hv));
cbec9347 1856 xhv->xhv_max = 7; /* HvMAX(hv) = 7 (it's a normal hash) */
7b2c381c 1857 HvARRAY(hv) = 0;
ca732855 1858 HvPLACEHOLDERS_set(hv, 0);
a0d0e21e
LW
1859
1860 if (SvRMAGICAL(hv))
1c846c1f 1861 mg_clear((SV*)hv);
79072805
LW
1862}
1863
b464bac0 1864static struct xpvhv_aux*
5f66b61c 1865S_hv_auxinit(HV *hv) {
bfcb3514 1866 struct xpvhv_aux *iter;
b79f7545 1867 char *array;
bfcb3514 1868
b79f7545 1869 if (!HvARRAY(hv)) {
a02a5408 1870 Newxz(array, PERL_HV_ARRAY_ALLOC_BYTES(HvMAX(hv) + 1)
b79f7545
NC
1871 + sizeof(struct xpvhv_aux), char);
1872 } else {
1873 array = (char *) HvARRAY(hv);
1874 Renew(array, PERL_HV_ARRAY_ALLOC_BYTES(HvMAX(hv) + 1)
1875 + sizeof(struct xpvhv_aux), char);
1876 }
1877 HvARRAY(hv) = (HE**) array;
1878 /* SvOOK_on(hv) attacks the IV flags. */
1879 SvFLAGS(hv) |= SVf_OOK;
1880 iter = HvAUX(hv);
bfcb3514
NC
1881
1882 iter->xhv_riter = -1; /* HvRITER(hv) = -1 */
4608196e 1883 iter->xhv_eiter = NULL; /* HvEITER(hv) = NULL */
bfcb3514 1884 iter->xhv_name = 0;
86f55936 1885 iter->xhv_backreferences = 0;
bfcb3514
NC
1886 return iter;
1887}
1888
954c1994
GS
1889/*
1890=for apidoc hv_iterinit
1891
1892Prepares a starting point to traverse a hash table. Returns the number of
1893keys in the hash (i.e. the same as C<HvKEYS(tb)>). The return value is
1c846c1f 1894currently only meaningful for hashes without tie magic.
954c1994
GS
1895
1896NOTE: Before version 5.004_65, C<hv_iterinit> used to return the number of
1897hash buckets that happen to be in use. If you still need that esoteric
1898value, you can get it through the macro C<HvFILL(tb)>.
1899
e16e2ff8 1900
954c1994
GS
1901=cut
1902*/
1903
79072805 1904I32
864dbfa3 1905Perl_hv_iterinit(pTHX_ HV *hv)
79072805 1906{
aa689395 1907 if (!hv)
cea2e8a9 1908 Perl_croak(aTHX_ "Bad hash");
bfcb3514 1909
b79f7545 1910 if (SvOOK(hv)) {
6136c704 1911 struct xpvhv_aux * const iter = HvAUX(hv);
0bd48802 1912 HE * const entry = iter->xhv_eiter; /* HvEITER(hv) */
bfcb3514
NC
1913 if (entry && HvLAZYDEL(hv)) { /* was deleted earlier? */
1914 HvLAZYDEL_off(hv);
1915 hv_free_ent(hv, entry);
1916 }
1917 iter->xhv_riter = -1; /* HvRITER(hv) = -1 */
4608196e 1918 iter->xhv_eiter = NULL; /* HvEITER(hv) = NULL */
bfcb3514 1919 } else {
6136c704 1920 hv_auxinit(hv);
72940dca 1921 }
bfcb3514 1922
cbec9347 1923 /* used to be xhv->xhv_fill before 5.004_65 */
5d88ecd7 1924 return HvTOTALKEYS(hv);
79072805 1925}
bfcb3514
NC
1926
1927I32 *
1928Perl_hv_riter_p(pTHX_ HV *hv) {
1929 struct xpvhv_aux *iter;
1930
1931 if (!hv)
1932 Perl_croak(aTHX_ "Bad hash");
1933
6136c704 1934 iter = SvOOK(hv) ? HvAUX(hv) : hv_auxinit(hv);
bfcb3514
NC
1935 return &(iter->xhv_riter);
1936}
1937
1938HE **
1939Perl_hv_eiter_p(pTHX_ HV *hv) {
1940 struct xpvhv_aux *iter;
1941
1942 if (!hv)
1943 Perl_croak(aTHX_ "Bad hash");
1944
6136c704 1945 iter = SvOOK(hv) ? HvAUX(hv) : hv_auxinit(hv);
bfcb3514
NC
1946 return &(iter->xhv_eiter);
1947}
1948
1949void
1950Perl_hv_riter_set(pTHX_ HV *hv, I32 riter) {
1951 struct xpvhv_aux *iter;
1952
1953 if (!hv)
1954 Perl_croak(aTHX_ "Bad hash");
1955
b79f7545
NC
1956 if (SvOOK(hv)) {
1957 iter = HvAUX(hv);
1958 } else {
bfcb3514
NC
1959 if (riter == -1)
1960 return;
1961
6136c704 1962 iter = hv_auxinit(hv);
bfcb3514
NC
1963 }
1964 iter->xhv_riter = riter;
1965}
1966
1967void
1968Perl_hv_eiter_set(pTHX_ HV *hv, HE *eiter) {
1969 struct xpvhv_aux *iter;
1970
1971 if (!hv)
1972 Perl_croak(aTHX_ "Bad hash");
1973
b79f7545
NC
1974 if (SvOOK(hv)) {
1975 iter = HvAUX(hv);
1976 } else {
bfcb3514
NC
1977 /* 0 is the default so don't go malloc()ing a new structure just to
1978 hold 0. */
1979 if (!eiter)
1980 return;
1981
6136c704 1982 iter = hv_auxinit(hv);
bfcb3514
NC
1983 }
1984 iter->xhv_eiter = eiter;
1985}
1986
bfcb3514 1987void
4164be69 1988Perl_hv_name_set(pTHX_ HV *hv, const char *name, U32 len, U32 flags)
bfcb3514 1989{
97aff369 1990 dVAR;
b79f7545 1991 struct xpvhv_aux *iter;
7423f6db 1992 U32 hash;
46c461b5
AL
1993
1994 PERL_UNUSED_ARG(flags);
bfcb3514 1995
4164be69
NC
1996 if (len > I32_MAX)
1997 Perl_croak(aTHX_ "panic: hv name too long (%"UVuf")", (UV) len);
1998
b79f7545
NC
1999 if (SvOOK(hv)) {
2000 iter = HvAUX(hv);
7423f6db
NC
2001 if (iter->xhv_name) {
2002 unshare_hek_or_pvn(iter->xhv_name, 0, 0, 0);
2003 }
16580ff5 2004 } else {
bfcb3514
NC
2005 if (name == 0)
2006 return;
2007
6136c704 2008 iter = hv_auxinit(hv);
bfcb3514 2009 }
7423f6db
NC
2010 PERL_HASH(hash, name, len);
2011 iter->xhv_name = name ? share_hek(name, len, hash) : 0;
bfcb3514
NC
2012}
2013
86f55936
NC
2014AV **
2015Perl_hv_backreferences_p(pTHX_ HV *hv) {
6136c704 2016 struct xpvhv_aux * const iter = SvOOK(hv) ? HvAUX(hv) : hv_auxinit(hv);
96a5add6 2017 PERL_UNUSED_CONTEXT;
86f55936
NC
2018 return &(iter->xhv_backreferences);
2019}
2020
2021void
2022Perl_hv_kill_backrefs(pTHX_ HV *hv) {
2023 AV *av;
2024
2025 if (!SvOOK(hv))
2026 return;
2027
2028 av = HvAUX(hv)->xhv_backreferences;
2029
2030 if (av) {
2031 HvAUX(hv)->xhv_backreferences = 0;
2032 Perl_sv_kill_backrefs(aTHX_ (SV*) hv, av);
2033 }
2034}
2035
954c1994 2036/*
7a7b9979
NC
2037hv_iternext is implemented as a macro in hv.h
2038
954c1994
GS
2039=for apidoc hv_iternext
2040
2041Returns entries from a hash iterator. See C<hv_iterinit>.
2042
fe7bca90
NC
2043You may call C<hv_delete> or C<hv_delete_ent> on the hash entry that the
2044iterator currently points to, without losing your place or invalidating your
2045iterator. Note that in this case the current entry is deleted from the hash
2046with your iterator holding the last reference to it. Your iterator is flagged
2047to free the entry on the next call to C<hv_iternext>, so you must not discard
2048your iterator immediately else the entry will leak - call C<hv_iternext> to
2049trigger the resource deallocation.
2050
fe7bca90
NC
2051=for apidoc hv_iternext_flags
2052
2053Returns entries from a hash iterator. See C<hv_iterinit> and C<hv_iternext>.
2054The C<flags> value will normally be zero; if HV_ITERNEXT_WANTPLACEHOLDERS is
2055set the placeholders keys (for restricted hashes) will be returned in addition
2056to normal keys. By default placeholders are automatically skipped over.
7996736c
MHM
2057Currently a placeholder is implemented with a value that is
2058C<&Perl_sv_placeholder>. Note that the implementation of placeholders and
fe7bca90
NC
2059restricted hashes may change, and the implementation currently is
2060insufficiently abstracted for any change to be tidy.
e16e2ff8 2061
fe7bca90 2062=cut
e16e2ff8
NC
2063*/
2064
2065HE *
2066Perl_hv_iternext_flags(pTHX_ HV *hv, I32 flags)
2067{
27da23d5 2068 dVAR;
cbec9347 2069 register XPVHV* xhv;
79072805 2070 register HE *entry;
a0d0e21e 2071 HE *oldentry;
463ee0b2 2072 MAGIC* mg;
bfcb3514 2073 struct xpvhv_aux *iter;
79072805
LW
2074
2075 if (!hv)
cea2e8a9 2076 Perl_croak(aTHX_ "Bad hash");
cbec9347 2077 xhv = (XPVHV*)SvANY(hv);
bfcb3514 2078
b79f7545 2079 if (!SvOOK(hv)) {
bfcb3514
NC
2080 /* Too many things (well, pp_each at least) merrily assume that you can
2081 call iv_iternext without calling hv_iterinit, so we'll have to deal
2082 with it. */
2083 hv_iterinit(hv);
bfcb3514 2084 }
b79f7545 2085 iter = HvAUX(hv);
bfcb3514
NC
2086
2087 oldentry = entry = iter->xhv_eiter; /* HvEITER(hv) */
463ee0b2 2088
14befaf4 2089 if ((mg = SvTIED_mg((SV*)hv, PERL_MAGIC_tied))) {
c4420975 2090 SV * const key = sv_newmortal();
cd1469e6 2091 if (entry) {
fde52b5c 2092 sv_setsv(key, HeSVKEY_force(entry));
cd1469e6
PP
2093 SvREFCNT_dec(HeSVKEY(entry)); /* get rid of previous key */
2094 }
a0d0e21e 2095 else {
ff68c719 2096 char *k;
bbce6d69 2097 HEK *hek;
ff68c719 2098
cbec9347 2099 /* one HE per MAGICAL hash */
bfcb3514 2100 iter->xhv_eiter = entry = new_HE(); /* HvEITER(hv) = new_HE() */
4633a7c4 2101 Zero(entry, 1, HE);
a02a5408 2102 Newxz(k, HEK_BASESIZE + sizeof(SV*), char);
ff68c719
PP
2103 hek = (HEK*)k;
2104 HeKEY_hek(entry) = hek;
fde52b5c 2105 HeKLEN(entry) = HEf_SVKEY;
a0d0e21e
LW
2106 }
2107 magic_nextpack((SV*) hv,mg,key);
8aacddc1 2108 if (SvOK(key)) {
cd1469e6 2109 /* force key to stay around until next time */
b37c2d43 2110 HeSVKEY_set(entry, SvREFCNT_inc_simple_NN(key));
bbce6d69 2111 return entry; /* beware, hent_val is not set */
8aacddc1 2112 }
fde52b5c
PP
2113 if (HeVAL(entry))
2114 SvREFCNT_dec(HeVAL(entry));
ff68c719 2115 Safefree(HeKEY_hek(entry));
d33b2eba 2116 del_HE(entry);
4608196e
RGS
2117 iter->xhv_eiter = NULL; /* HvEITER(hv) = NULL */
2118 return NULL;
79072805 2119 }
7ee146b1 2120#if defined(DYNAMIC_ENV_FETCH) && !defined(__riscos__) /* set up %ENV for iteration */
03026e68 2121 if (!entry && SvRMAGICAL((SV*)hv) && mg_find((SV*)hv, PERL_MAGIC_env)) {
f675dbe5 2122 prime_env_iter();
03026e68
JM
2123#ifdef VMS
2124 /* The prime_env_iter() on VMS just loaded up new hash values
2125 * so the iteration count needs to be reset back to the beginning
2126 */
2127 hv_iterinit(hv);
2128 iter = HvAUX(hv);
2129 oldentry = entry = iter->xhv_eiter; /* HvEITER(hv) */
2130#endif
2131 }
f675dbe5 2132#endif
463ee0b2 2133
b79f7545
NC
2134 /* hv_iterint now ensures this. */
2135 assert (HvARRAY(hv));
2136
015a5f36 2137 /* At start of hash, entry is NULL. */
fde52b5c 2138 if (entry)
8aacddc1 2139 {
fde52b5c 2140 entry = HeNEXT(entry);
e16e2ff8
NC
2141 if (!(flags & HV_ITERNEXT_WANTPLACEHOLDERS)) {
2142 /*
2143 * Skip past any placeholders -- don't want to include them in
2144 * any iteration.
2145 */
7996736c 2146 while (entry && HeVAL(entry) == &PL_sv_placeholder) {
e16e2ff8
NC
2147 entry = HeNEXT(entry);
2148 }
8aacddc1
NIS
2149 }
2150 }
fde52b5c 2151 while (!entry) {
015a5f36
NC
2152 /* OK. Come to the end of the current list. Grab the next one. */
2153
bfcb3514
NC
2154 iter->xhv_riter++; /* HvRITER(hv)++ */
2155 if (iter->xhv_riter > (I32)xhv->xhv_max /* HvRITER(hv) > HvMAX(hv) */) {
015a5f36 2156 /* There is no next one. End of the hash. */
bfcb3514 2157 iter->xhv_riter = -1; /* HvRITER(hv) = -1 */
fde52b5c 2158 break;
79072805 2159 }
7b2c381c 2160 entry = (HvARRAY(hv))[iter->xhv_riter];
8aacddc1 2161
e16e2ff8 2162 if (!(flags & HV_ITERNEXT_WANTPLACEHOLDERS)) {
015a5f36
NC
2163 /* If we have an entry, but it's a placeholder, don't count it.
2164 Try the next. */
7996736c 2165 while (entry && HeVAL(entry) == &PL_sv_placeholder)
015a5f36
NC
2166 entry = HeNEXT(entry);
2167 }
2168 /* Will loop again if this linked list starts NULL
2169 (for HV_ITERNEXT_WANTPLACEHOLDERS)
2170 or if we run through it and find only placeholders. */
fde52b5c 2171 }
79072805 2172
72940dca
PP
2173 if (oldentry && HvLAZYDEL(hv)) { /* was deleted earlier? */
2174 HvLAZYDEL_off(hv);
68dc0745 2175 hv_free_ent(hv, oldentry);
72940dca 2176 }
a0d0e21e 2177
fdcd69b6
NC
2178 /*if (HvREHASH(hv) && entry && !HeKREHASH(entry))
2179 PerlIO_printf(PerlIO_stderr(), "Awooga %p %p\n", hv, entry);*/
2180
bfcb3514 2181 iter->xhv_eiter = entry; /* HvEITER(hv) = entry */
79072805
LW
2182 return entry;
2183}
2184
954c1994
GS
2185/*
2186=for apidoc hv_iterkey
2187
2188Returns the key from the current position of the hash iterator. See
2189C<hv_iterinit>.
2190
2191=cut
2192*/
2193
79072805 2194char *
864dbfa3 2195Perl_hv_iterkey(pTHX_ register HE *entry, I32 *retlen)
79072805 2196{
fde52b5c 2197 if (HeKLEN(entry) == HEf_SVKEY) {
fb73857a 2198 STRLEN len;
0bd48802 2199 char * const p = SvPV(HeKEY_sv(entry), len);
fb73857a
PP
2200 *retlen = len;
2201 return p;
fde52b5c
PP
2202 }
2203 else {
2204 *retlen = HeKLEN(entry);
2205 return HeKEY(entry);
2206 }
2207}
2208
2209/* unlike hv_iterval(), this always returns a mortal copy of the key */
954c1994
GS
2210/*
2211=for apidoc hv_iterkeysv
2212
2213Returns the key as an C<SV*> from the current position of the hash
2214iterator. The return value will always be a mortal copy of the key. Also
2215see C<hv_iterinit>.
2216
2217=cut
2218*/
2219
fde52b5c 2220SV *
864dbfa3 2221Perl_hv_iterkeysv(pTHX_ register HE *entry)
fde52b5c 2222{
c1b02ed8 2223 return sv_2mortal(newSVhek(HeKEY_hek(entry)));
79072805
LW
2224}
2225
954c1994
GS
2226/*
2227=for apidoc hv_iterval
2228
2229Returns the value from the current position of the hash iterator. See
2230C<hv_iterkey>.
2231
2232=cut
2233*/
2234
79072805 2235SV *
864dbfa3 2236Perl_hv_iterval(pTHX_ HV *hv, register HE *entry)
79072805 2237{
8990e307 2238 if (SvRMAGICAL(hv)) {
14befaf4 2239 if (mg_find((SV*)hv, PERL_MAGIC_tied)) {
c4420975 2240 SV* const sv = sv_newmortal();
bbce6d69
PP
2241 if (HeKLEN(entry) == HEf_SVKEY)
2242 mg_copy((SV*)hv, sv, (char*)HeKEY_sv(entry), HEf_SVKEY);
a3b680e6
AL
2243 else
2244 mg_copy((SV*)hv, sv, HeKEY(entry), HeKLEN(entry));
463ee0b2
LW
2245 return sv;
2246 }
79072805 2247 }
fde52b5c 2248 return HeVAL(entry);
79072805
LW
2249}
2250
954c1994
GS
2251/*
2252=for apidoc hv_iternextsv
2253
2254Performs an C<hv_iternext>, C<hv_iterkey>, and C<hv_iterval> in one
2255operation.
2256
2257=cut
2258*/
2259
a0d0e21e 2260SV *
864dbfa3 2261Perl_hv_iternextsv(pTHX_ HV *hv, char **key, I32 *retlen)
a0d0e21e 2262{
0bd48802
AL
2263 HE * const he = hv_iternext_flags(hv, 0);
2264
2265 if (!he)
a0d0e21e
LW
2266 return NULL;
2267 *key = hv_iterkey(he, retlen);
2268 return hv_iterval(hv, he);
2269}
2270
954c1994 2271/*
bc5cdc23
NC
2272
2273Now a macro in hv.h
2274
954c1994
GS
2275=for apidoc hv_magic
2276
2277Adds magic to a hash. See C<sv_magic>.
2278
2279=cut
2280*/
2281
bbce6d69 2282/* possibly free a shared string if no one has access to it
fde52b5c
PP
2283 * len and hash must both be valid for str.
2284 */
bbce6d69 2285void
864dbfa3 2286Perl_unsharepvn(pTHX_ const char *str, I32 len, U32 hash)
fde52b5c 2287{
19692e8d
NC
2288 unshare_hek_or_pvn (NULL, str, len, hash);
2289}
2290
2291
2292void
2293Perl_unshare_hek(pTHX_ HEK *hek)
2294{
2295 unshare_hek_or_pvn(hek, NULL, 0, 0);
2296}
2297
2298/* possibly free a shared string if no one has access to it
2299 hek if non-NULL takes priority over the other 3, else str, len and hash
2300 are used. If so, len and hash must both be valid for str.
2301 */
df132699 2302STATIC void
97ddebaf 2303S_unshare_hek_or_pvn(pTHX_ const HEK *hek, const char *str, I32 len, U32 hash)
19692e8d 2304{
97aff369 2305 dVAR;
cbec9347 2306 register XPVHV* xhv;
20454177 2307 HE *entry;
fde52b5c 2308 register HE **oentry;
45d1cc86 2309 HE **first;
c3654f1a 2310 bool is_utf8 = FALSE;
19692e8d 2311 int k_flags = 0;
aec46f14 2312 const char * const save = str;
cbbf8932 2313 struct shared_he *he = NULL;
c3654f1a 2314
19692e8d 2315 if (hek) {
cbae3960
NC
2316 /* Find the shared he which is just before us in memory. */
2317 he = (struct shared_he *)(((char *)hek)
2318 - STRUCT_OFFSET(struct shared_he,
2319 shared_he_hek));
2320
2321 /* Assert that the caller passed us a genuine (or at least consistent)
2322 shared hek */
2323 assert (he->shared_he_he.hent_hek == hek);
29404ae0
NC
2324
2325 LOCK_STRTAB_MUTEX;
de616631
NC
2326 if (he->shared_he_he.he_valu.hent_refcount - 1) {
2327 --he->shared_he_he.he_valu.hent_refcount;
29404ae0
NC
2328 UNLOCK_STRTAB_MUTEX;
2329 return;
2330 }
2331 UNLOCK_STRTAB_MUTEX;
2332
19692e8d
NC
2333 hash = HEK_HASH(hek);
2334 } else if (len < 0) {
2335 STRLEN tmplen = -len;
2336 is_utf8 = TRUE;
2337 /* See the note in hv_fetch(). --jhi */
2338 str = (char*)bytes_from_utf8((U8*)str, &tmplen, &is_utf8);
2339 len = tmplen;
2340 if (is_utf8)
2341 k_flags = HVhek_UTF8;
2342 if (str != save)
2343 k_flags |= HVhek_WASUTF8 | HVhek_FREEKEY;
c3654f1a 2344 }
1c846c1f 2345
de616631 2346 /* what follows was the moral equivalent of:
6b88bc9c 2347 if ((Svp = hv_fetch(PL_strtab, tmpsv, FALSE, hash))) {
a0714e2c 2348 if (--*Svp == NULL)
6b88bc9c 2349 hv_delete(PL_strtab, str, len, G_DISCARD, hash);
bbce6d69 2350 } */
cbec9347 2351 xhv = (XPVHV*)SvANY(PL_strtab);
fde52b5c 2352 /* assert(xhv_array != 0) */
5f08fbcd 2353 LOCK_STRTAB_MUTEX;
45d1cc86 2354 first = oentry = &(HvARRAY(PL_strtab))[hash & (I32) HvMAX(PL_strtab)];
6c1b96a1
NC
2355 if (he) {
2356 const HE *const he_he = &(he->shared_he_he);
45d1cc86 2357 for (entry = *oentry; entry; oentry = &HeNEXT(entry), entry = *oentry) {
35ab5632
NC
2358 if (entry == he_he)
2359 break;
19692e8d
NC
2360 }
2361 } else {
35a4481c 2362 const int flags_masked = k_flags & HVhek_MASK;
45d1cc86 2363 for (entry = *oentry; entry; oentry = &HeNEXT(entry), entry = *oentry) {
19692e8d
NC
2364 if (HeHASH(entry) != hash) /* strings can't be equal */
2365 continue;
2366 if (HeKLEN(entry) != len)
2367 continue;
2368 if (HeKEY(entry) != str && memNE(HeKEY(entry),str,len)) /* is this it? */
2369 continue;
2370 if (HeKFLAGS(entry) != flags_masked)
2371 continue;
19692e8d
NC
2372 break;
2373 }
2374 }
2375
35ab5632
NC
2376 if (entry) {
2377 if (--entry->he_valu.hent_refcount == 0) {
19692e8d 2378 *oentry = HeNEXT(entry);
45d1cc86
NC
2379 if (!*first) {
2380 /* There are now no entries in our slot. */
19692e8d 2381 xhv->xhv_fill--; /* HvFILL(hv)-- */
45d1cc86 2382 }
cbae3960 2383 Safefree(entry);
4c7185a0 2384 xhv->xhv_keys--; /* HvTOTALKEYS(hv)-- */
19692e8d 2385 }
fde52b5c 2386 }
19692e8d 2387
333f433b 2388 UNLOCK_STRTAB_MUTEX;
35ab5632 2389 if (!entry && ckWARN_d(WARN_INTERNAL))
19692e8d 2390 Perl_warner(aTHX_ packWARN(WARN_INTERNAL),
472d47bc
SB
2391 "Attempt to free non-existent shared string '%s'%s"
2392 pTHX__FORMAT,
19692e8d 2393 hek ? HEK_KEY(hek) : str,
472d47bc 2394 ((k_flags & HVhek_UTF8) ? " (utf8)" : "") pTHX__VALUE);
19692e8d
NC
2395 if (k_flags & HVhek_FREEKEY)
2396 Safefree(str);
fde52b5c
PP
2397}
2398
bbce6d69
PP
2399/* get a (constant) string ptr from the global string table
2400 * string will get added if it is not already there.
fde52b5c
PP
2401 * len and hash must both be valid for str.
2402 */
bbce6d69 2403HEK *
864dbfa3 2404Perl_share_hek(pTHX_ const char *str, I32 len, register U32 hash)
fde52b5c 2405{
da58a35d 2406 bool is_utf8 = FALSE;
19692e8d 2407 int flags = 0;
aec46f14 2408 const char * const save = str;
da58a35d
JH
2409
2410 if (len < 0) {
77caf834 2411 STRLEN tmplen = -len;
da58a35d 2412 is_utf8 = TRUE;
77caf834
JH
2413 /* See the note in hv_fetch(). --jhi */
2414 str = (char*)bytes_from_utf8((U8*)str, &tmplen, &is_utf8);
2415 len = tmplen;
19692e8d
NC
2416 /* If we were able to downgrade here, then than means that we were passed
2417 in a key which only had chars 0-255, but was utf8 encoded. */
2418 if (is_utf8)
2419 flags = HVhek_UTF8;
2420 /* If we found we were able to downgrade the string to bytes, then
2421 we should flag that it needs upgrading on keys or each. Also flag
2422 that we need share_hek_flags to free the string. */
2423 if (str != save)
2424 flags |= HVhek_WASUTF8 | HVhek_FREEKEY;
2425 }
2426
6e838c70 2427 return share_hek_flags (str, len, hash, flags);
19692e8d
NC
2428}
2429
6e838c70 2430STATIC HEK *
19692e8d
NC
2431S_share_hek_flags(pTHX_ const char *str, I32 len, register U32 hash, int flags)
2432{
97aff369 2433 dVAR;
19692e8d 2434 register HE *entry;
35a4481c 2435 const int flags_masked = flags & HVhek_MASK;
263cb4a6 2436 const U32 hindex = hash & (I32) HvMAX(PL_strtab);
bbce6d69 2437
fde52b5c 2438 /* what follows is the moral equivalent of:
1c846c1f 2439
6b88bc9c 2440 if (!(Svp = hv_fetch(PL_strtab, str, len, FALSE)))
a0714e2c 2441 hv_store(PL_strtab, str, len, NULL, hash);
fdcd69b6
NC
2442
2443 Can't rehash the shared string table, so not sure if it's worth
2444 counting the number of entries in the linked list
bbce6d69 2445 */
1b6737cc 2446 register XPVHV * const xhv = (XPVHV*)SvANY(PL_strtab);
fde52b5c 2447 /* assert(xhv_array != 0) */
5f08fbcd 2448 LOCK_STRTAB_MUTEX;
263cb4a6
NC
2449 entry = (HvARRAY(PL_strtab))[hindex];
2450 for (;entry; entry = HeNEXT(entry)) {
fde52b5c
PP
2451 if (HeHASH(entry) != hash) /* strings can't be equal */
2452 continue;
2453 if (HeKLEN(entry) != len)
2454 continue;
1c846c1f 2455 if (HeKEY(entry) != str && memNE(HeKEY(entry),str,len)) /* is this it? */
fde52b5c 2456 continue;
19692e8d 2457 if (HeKFLAGS(entry) != flags_masked)
c3654f1a 2458 continue;
fde52b5c
PP
2459 break;
2460 }
263cb4a6
NC
2461
2462 if (!entry) {
45d1cc86
NC
2463 /* What used to be head of the list.
2464 If this is NULL, then we're the first entry for this slot, which
2465 means we need to increate fill. */
cbae3960
NC
2466 struct shared_he *new_entry;
2467 HEK *hek;
2468 char *k;
263cb4a6
NC
2469 HE **const head = &HvARRAY(PL_strtab)[hindex];
2470 HE *const next = *head;
cbae3960
NC
2471
2472 /* We don't actually store a HE from the arena and a regular HEK.
2473 Instead we allocate one chunk of memory big enough for both,
2474 and put the HEK straight after the HE. This way we can find the
2475 HEK directly from the HE.
2476 */
2477
a02a5408 2478 Newx(k, STRUCT_OFFSET(struct shared_he,
cbae3960
NC
2479 shared_he_hek.hek_key[0]) + len + 2, char);
2480 new_entry = (struct shared_he *)k;
2481 entry = &(new_entry->shared_he_he);
2482 hek = &(new_entry->shared_he_hek);
2483
2484 Copy(str, HEK_KEY(hek), len, char);
2485 HEK_KEY(hek)[len] = 0;
2486 HEK_LEN(hek) = len;
2487 HEK_HASH(hek) = hash;
2488 HEK_FLAGS(hek) = (unsigned char)flags_masked;
2489
2490 /* Still "point" to the HEK, so that other code need not know what
2491 we're up to. */
2492 HeKEY_hek(entry) = hek;
de616631 2493 entry->he_valu.hent_refcount = 0;
263cb4a6
NC
2494 HeNEXT(entry) = next;
2495 *head = entry;
cbae3960 2496
4c7185a0 2497 xhv->xhv_keys++; /* HvTOTALKEYS(hv)++ */
263cb4a6 2498 if (!next) { /* initial entry? */
cbec9347 2499 xhv->xhv_fill++; /* HvFILL(hv)++ */
4c9cc595 2500 } else if (xhv->xhv_keys > (IV)xhv->xhv_max /* HvKEYS(hv) > HvMAX(hv) */) {
cbec9347 2501 hsplit(PL_strtab);
bbce6d69
PP
2502 }
2503 }
2504
de616631 2505 ++entry->he_valu.hent_refcount;
5f08fbcd 2506 UNLOCK_STRTAB_MUTEX;
19692e8d
NC
2507
2508 if (flags & HVhek_FREEKEY)
f9a63242 2509 Safefree(str);
19692e8d 2510
6e838c70 2511 return HeKEY_hek(entry);
fde52b5c 2512}
ecae49c0 2513
ca732855
NC
2514I32 *
2515Perl_hv_placeholders_p(pTHX_ HV *hv)
2516{
2517 dVAR;
2518 MAGIC *mg = mg_find((SV*)hv, PERL_MAGIC_rhash);
2519
2520 if (!mg) {
2521 mg = sv_magicext((SV*)hv, 0, PERL_MAGIC_rhash, 0, 0, 0);
2522
2523 if (!mg) {
2524 Perl_die(aTHX_ "panic: hv_placeholders_p");
2525 }
2526 }
2527 return &(mg->mg_len);
2528}
2529
2530
2531I32
2532Perl_hv_placeholders_get(pTHX_ HV *hv)
2533{
2534 dVAR;
b464bac0 2535 MAGIC * const mg = mg_find((SV*)hv, PERL_MAGIC_rhash);
ca732855
NC
2536
2537 return mg ? mg->mg_len : 0;
2538}
2539
2540void
ac1e784a 2541Perl_hv_placeholders_set(pTHX_ HV *hv, I32 ph)
ca732855
NC
2542{
2543 dVAR;
b464bac0 2544 MAGIC * const mg = mg_find((SV*)hv, PERL_MAGIC_rhash);
ca732855
NC
2545
2546 if (mg) {
2547 mg->mg_len = ph;
2548 } else if (ph) {
2549 if (!sv_magicext((SV*)hv, 0, PERL_MAGIC_rhash, 0, 0, ph))
2550 Perl_die(aTHX_ "panic: hv_placeholders_set");
2551 }
2552 /* else we don't need to add magic to record 0 placeholders. */
2553}
ecae49c0 2554
7b0bddfa
NC
2555SV *
2556S_refcounted_he_value(pTHX_ const struct refcounted_he *he)
2557{
2558 SV *value;
2559 switch(he->refcounted_he_data[0] & HVrhek_typemask) {
2560 case HVrhek_undef:
2561 value = newSV(0);
2562 break;
2563 case HVrhek_delete:
2564 value = &PL_sv_placeholder;
2565 break;
2566 case HVrhek_IV:
2567 value = (he->refcounted_he_data[0] & HVrhek_UV)
2568 ? newSVuv(he->refcounted_he_val.refcounted_he_u_iv)
2569 : newSViv(he->refcounted_he_val.refcounted_he_u_uv);
2570 break;
2571 case HVrhek_PV:
2572 /* Create a string SV that directly points to the bytes in our
2573 structure. */
2574 value = newSV(0);
2575 sv_upgrade(value, SVt_PV);
2576 SvPV_set(value, (char *) he->refcounted_he_data + 1);
2577 SvCUR_set(value, he->refcounted_he_val.refcounted_he_u_len);
2578 /* This stops anything trying to free it */
2579 SvLEN_set(value, 0);
2580 SvPOK_on(value);
2581 SvREADONLY_on(value);
2582 if (he->refcounted_he_data[0] & HVrhek_UTF8)
2583 SvUTF8_on(value);
2584 break;
2585 default:
2586 Perl_croak(aTHX_ "panic: refcounted_he_value bad flags %x",
2587 he->refcounted_he_data[0]);
2588 }
2589 return value;
2590}
2591
2592#ifdef USE_ITHREADS
2593/* A big expression to find the key offset */
2594#define REF_HE_KEY(chain) \
2595 ((((chain->refcounted_he_data[0] & HVrhek_typemask) == HVrhek_PV) \
2596 ? chain->refcounted_he_val.refcounted_he_u_len + 1 : 0) \
2597 + 1 + chain->refcounted_he_data)
2598#endif
2599
ecae49c0 2600/*
b3ca2e83
NC
2601=for apidoc refcounted_he_chain_2hv
2602
2603Generates an returns a C<HV *> by walking up the tree starting at the passed
2604in C<struct refcounted_he *>.
2605
2606=cut
2607*/
2608HV *
2609Perl_refcounted_he_chain_2hv(pTHX_ const struct refcounted_he *chain)
2610{
7a89be66 2611 dVAR;
b3ca2e83
NC
2612 HV *hv = newHV();
2613 U32 placeholders = 0;
2614 /* We could chase the chain once to get an idea of the number of keys,
2615 and call ksplit. But for now we'll make a potentially inefficient
2616 hash with only 8 entries in its array. */
2617 const U32 max = HvMAX(hv);
2618
2619 if (!HvARRAY(hv)) {
2620 char *array;
2621 Newxz(array, PERL_HV_ARRAY_ALLOC_BYTES(max + 1), char);
2622 HvARRAY(hv) = (HE**)array;
2623 }
2624
2625 while (chain) {
cbb1fbea 2626#ifdef USE_ITHREADS
b6bbf3fa 2627 U32 hash = chain->refcounted_he_hash;
cbb1fbea
NC
2628#else
2629 U32 hash = HEK_HASH(chain->refcounted_he_hek);
2630#endif
b3ca2e83
NC
2631 HE **oentry = &((HvARRAY(hv))[hash & max]);
2632 HE *entry = *oentry;
b6bbf3fa 2633 SV *value;
cbb1fbea 2634
b3ca2e83
NC
2635 for (; entry; entry = HeNEXT(entry)) {
2636 if (HeHASH(entry) == hash) {
2637 goto next_please;
2638 }
2639 }
2640 assert (!entry);
2641 entry = new_HE();
2642
cbb1fbea
NC
2643#ifdef USE_ITHREADS
2644 HeKEY_hek(entry)
7b0bddfa 2645 = share_hek_flags(REF_HE_KEY(chain),
b6bbf3fa
NC
2646 chain->refcounted_he_keylen,
2647 chain->refcounted_he_hash,
2648 (chain->refcounted_he_data[0]
2649 & (HVhek_UTF8|HVhek_WASUTF8)));
cbb1fbea 2650#else
71ad1b0c 2651 HeKEY_hek(entry) = share_hek_hek(chain->refcounted_he_hek);
cbb1fbea 2652#endif
7b0bddfa
NC
2653 value = refcounted_he_value(chain);
2654 if (value == &PL_sv_placeholder)
b3ca2e83 2655 placeholders++;
b6bbf3fa 2656 HeVAL(entry) = value;
b3ca2e83
NC
2657
2658 /* Link it into the chain. */
2659 HeNEXT(entry) = *oentry;
2660 if (!HeNEXT(entry)) {
2661 /* initial entry. */
2662 HvFILL(hv)++;
2663 }
2664 *oentry = entry;
2665
2666 HvTOTALKEYS(hv)++;
2667
2668 next_please:
71ad1b0c 2669 chain = chain->refcounted_he_next;
b3ca2e83
NC
2670 }
2671
2672 if (placeholders) {
2673 clear_placeholders(hv, placeholders);
2674 HvTOTALKEYS(hv) -= placeholders;
2675 }
2676
2677 /* We could check in the loop to see if we encounter any keys with key
2678 flags, but it's probably not worth it, as this per-hash flag is only
2679 really meant as an optimisation for things like Storable. */
2680 HvHASKFLAGS_on(hv);
def9038f 2681 DEBUG_A(Perl_hv_assert(aTHX_ hv));
b3ca2e83
NC
2682
2683 return hv;
2684}
2685
7b0bddfa
NC
2686SV *
2687Perl_refcounted_he_fetch(pTHX_ const struct refcounted_he *chain, SV *keysv,
2688 const char *key, STRLEN klen, int flags, U32 hash)
2689{
2690 /* Just to be awkward, if you're using this interface the UTF-8-or-not-ness
2691 of your key has to exactly match that which is stored. */
2692 SV *value = &PL_sv_placeholder;
7b0bddfa
NC
2693
2694 if (keysv) {
2695 if (flags & HVhek_FREEKEY)
2696 Safefree(key);
2697 key = SvPV_const(keysv, klen);
2698 flags = 0;
7b0bddfa
NC
2699 }
2700
2701 if (!hash) {
2702 if (keysv && (SvIsCOW_shared_hash(keysv))) {
2703 hash = SvSHARED_HASH(keysv);
2704 } else {
2705 PERL_HASH(hash, key, klen);
2706 }
2707 }
2708
2709 for (; chain; chain = chain->refcounted_he_next) {
2710#ifdef USE_ITHREADS
2711 if (hash != chain->refcounted_he_hash)
2712 continue;
2713 if (klen != chain->refcounted_he_keylen)
2714 continue;
2715 if (memNE(REF_HE_KEY(chain),key,klen))
2716 continue;
2717#else
2718 if (hash != HEK_HASH(chain->refcounted_he_hek))
2719 continue;
2720 if (klen != HEK_LEN(chain->refcounted_he_hek))
2721 continue;
2722 if (memNE(HEK_KEY(chain->refcounted_he_hek),key,klen))
2723 continue;
2724#endif
2725
2726 value = sv_2mortal(refcounted_he_value(chain));
2727 break;
2728 }
2729
2730 if (flags & HVhek_FREEKEY)
2731 Safefree(key);
2732
2733 return value;
2734}
2735
b3ca2e83
NC
2736/*
2737=for apidoc refcounted_he_new
2738
ec2a1de7
NC
2739Creates a new C<struct refcounted_he>. As S<key> is copied, and value is
2740stored in a compact form, all references remain the property of the caller.
2741The C<struct refcounted_he> is returned with a reference count of 1.
b3ca2e83
NC
2742
2743=cut
2744*/
2745
2746struct refcounted_he *
2747Perl_refcounted_he_new(pTHX_ struct refcounted_he *const parent,
2748 SV *const key, SV *const value) {
7a89be66 2749 dVAR;
b3ca2e83 2750 struct refcounted_he *he;
b6bbf3fa
NC
2751 STRLEN key_len;
2752 const char *key_p = SvPV_const(key, key_len);
2753 STRLEN value_len = 0;
95b63a38 2754 const char *value_p = NULL;
b6bbf3fa
NC
2755 char value_type;
2756 char flags;
2757 STRLEN key_offset;
b3ca2e83 2758 U32 hash;
b6bbf3fa
NC
2759 bool is_utf8 = SvUTF8(key);
2760
2761 if (SvPOK(value)) {
2762 value_type = HVrhek_PV;
2763 } else if (SvIOK(value)) {
2764 value_type = HVrhek_IV;
2765 } else if (value == &PL_sv_placeholder) {
2766 value_type = HVrhek_delete;
2767 } else if (!SvOK(value)) {
2768 value_type = HVrhek_undef;
2769 } else {
2770 value_type = HVrhek_PV;
2771 }
b3ca2e83 2772
b6bbf3fa
NC
2773 if (value_type == HVrhek_PV) {
2774 value_p = SvPV_const(value, value_len);
2775 key_offset = value_len + 2;
2776 } else {
2777 value_len = 0;
2778 key_offset = 1;
2779 }
2780 flags = value_type;
2781
b6bbf3fa 2782#ifdef USE_ITHREADS
6cef672b 2783 he = PerlMemShared_malloc(sizeof(struct refcounted_he) - 1
b6bbf3fa 2784 + key_len
b6bbf3fa 2785 + key_offset);
6cef672b
NC
2786#else
2787 he = PerlMemShared_malloc(sizeof(struct refcounted_he) - 1
2788 + key_offset);
2789#endif
b3ca2e83 2790
b3ca2e83 2791
71ad1b0c 2792 he->refcounted_he_next = parent;
b6bbf3fa
NC
2793
2794 if (value_type == HVrhek_PV) {
2795 Copy(value_p, he->refcounted_he_data + 1, value_len + 1, char);
2796 he->refcounted_he_val.refcounted_he_u_len = value_len;
2797 if (SvUTF8(value)) {
2798 flags |= HVrhek_UTF8;
2799 }
2800 } else if (value_type == HVrhek_IV) {
2801 if (SvUOK(value)) {
2802 he->refcounted_he_val.refcounted_he_u_uv = SvUVX(value);
2803 flags |= HVrhek_UV;
2804 } else {
2805 he->refcounted_he_val.refcounted_he_u_iv = SvIVX(value);
2806 }
2807 }
2808
2809 if (is_utf8) {
2810 /* Hash keys are always stored normalised to (yes) ISO-8859-1.
2811 As we're going to be building hash keys from this value in future,
2812 normalise it now. */
2813 key_p = (char*)bytes_from_utf8((const U8*)key_p, &key_len, &is_utf8);
2814 flags |= is_utf8 ? HVhek_UTF8 : HVhek_WASUTF8;
2815 }
2816 PERL_HASH(hash, key_p, key_len);
2817
cbb1fbea 2818#ifdef USE_ITHREADS
b6bbf3fa
NC
2819 he->refcounted_he_hash = hash;
2820 he->refcounted_he_keylen = key_len;
2821 Copy(key_p, he->refcounted_he_data + key_offset, key_len, char);
cbb1fbea 2822#else
b6bbf3fa 2823 he->refcounted_he_hek = share_hek_flags(key_p, key_len, hash, flags);
cbb1fbea 2824#endif
b6bbf3fa
NC
2825
2826 if (flags & HVhek_WASUTF8) {
2827 /* If it was downgraded from UTF-8, then the pointer returned from
2828 bytes_from_utf8 is an allocated pointer that we must free. */
2829 Safefree(key_p);
2830 }
2831
2832 he->refcounted_he_data[0] = flags;
b3ca2e83
NC
2833 he->refcounted_he_refcnt = 1;
2834
2835 return he;
2836}
2837
2838/*
2839=for apidoc refcounted_he_free
2840
2841Decrements the reference count of the passed in C<struct refcounted_he *>
2842by one. If the reference count reaches zero the structure's memory is freed,
2843and C<refcounted_he_free> iterates onto the parent node.
2844
2845=cut
2846*/
2847
2848void
2849Perl_refcounted_he_free(pTHX_ struct refcounted_he *he) {
57ca3b03
AL
2850 PERL_UNUSED_CONTEXT;
2851
b3ca2e83
NC
2852 while (he) {
2853 struct refcounted_he *copy;
cbb1fbea 2854 U32 new_count;
b3ca2e83 2855
cbb1fbea
NC
2856 HINTS_REFCNT_LOCK;
2857 new_count = --he->refcounted_he_refcnt;
2858 HINTS_REFCNT_UNLOCK;
2859
2860 if (new_count) {
b3ca2e83 2861 return;
cbb1fbea 2862 }
b3ca2e83 2863
b6bbf3fa 2864#ifndef USE_ITHREADS
71ad1b0c 2865 unshare_hek_or_pvn (he->refcounted_he_hek, 0, 0, 0);
cbb1fbea 2866#endif
b3ca2e83 2867 copy = he;
71ad1b0c 2868 he = he->refcounted_he_next;
b6bbf3fa 2869 PerlMemShared_free(copy);
b3ca2e83
NC
2870 }
2871}
2872
b3ca2e83 2873/*
ecae49c0
NC
2874=for apidoc hv_assert
2875
2876Check that a hash is in an internally consistent state.
2877
2878=cut
2879*/
2880
943795c2
NC
2881#ifdef DEBUGGING
2882
ecae49c0
NC
2883void
2884Perl_hv_assert(pTHX_ HV *hv)
2885{
57ca3b03
AL
2886 dVAR;
2887 HE* entry;
2888 int withflags = 0;
2889 int placeholders = 0;
2890 int real = 0;
2891 int bad = 0;
2892 const I32 riter = HvRITER_get(hv);
2893 HE *eiter = HvEITER_get(hv);
2894
2895 (void)hv_iterinit(hv);
2896
2897 while ((entry = hv_iternext_flags(hv, HV_ITERNEXT_WANTPLACEHOLDERS))) {
2898 /* sanity check the values */
2899 if (HeVAL(entry) == &PL_sv_placeholder)
2900 placeholders++;
2901 else
2902 real++;
2903 /* sanity check the keys */
2904 if (HeSVKEY(entry)) {
6f207bd3 2905 NOOP; /* Don't know what to check on SV keys. */
57ca3b03
AL
2906 } else if (HeKUTF8(entry)) {
2907 withflags++;
2908 if (HeKWASUTF8(entry)) {
2909 PerlIO_printf(Perl_debug_log,
2910 "hash key has both WASUFT8 and UTF8: '%.*s'\n",
2911 (int) HeKLEN(entry), HeKEY(entry));
2912 bad = 1;
2913 }
2914 } else if (HeKWASUTF8(entry))
2915 withflags++;
2916 }
2917 if (!SvTIED_mg((SV*)hv, PERL_MAGIC_tied)) {
2918 static const char bad_count[] = "Count %d %s(s), but hash reports %d\n";
2919 const int nhashkeys = HvUSEDKEYS(hv);
2920 const int nhashplaceholders = HvPLACEHOLDERS_get(hv);
2921
2922 if (nhashkeys != real) {
2923 PerlIO_printf(Perl_debug_log, bad_count, real, "keys", nhashkeys );
2924 bad = 1;
2925 }
2926 if (nhashplaceholders != placeholders) {
2927 PerlIO_printf(Perl_debug_log, bad_count, placeholders, "placeholder", nhashplaceholders );
2928 bad = 1;
2929 }
2930 }
2931 if (withflags && ! HvHASKFLAGS(hv)) {
2932 PerlIO_printf(Perl_debug_log,
2933 "Hash has HASKFLAGS off but I count %d key(s) with flags\n",
2934 withflags);
2935 bad = 1;
2936 }
2937 if (bad) {
2938 sv_dump((SV *)hv);
2939 }
2940 HvRITER_set(hv, riter); /* Restore hash iterator state */
2941 HvEITER_set(hv, eiter);
ecae49c0 2942}
af3babe4 2943
943795c2
NC
2944#endif
2945
af3babe4
NC
2946/*
2947 * Local variables:
2948 * c-indentation-style: bsd
2949 * c-basic-offset: 4
2950 * indent-tabs-mode: t
2951 * End:
2952 *
37442d52
RGS
2953 * ex: set ts=8 sts=4 sw=4 noet:
2954 */