1 /* hv.c 2 * 3 * Copyright (C) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 4 * 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008 by Larry Wall and others 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 * 9 */ 10 11 /* 12 * I sit beside the fire and think 13 * of all that I have seen. 14 * --Bilbo 15 * 16 * [p.278 of _The Lord of the Rings_, II/iii: "The Ring Goes South"] 17 */ 18 19 /* 20 =head1 Hash Manipulation Functions 21 22 A HV structure represents a Perl hash. It consists mainly of an array 23 of pointers, each of which points to a linked list of HE structures. The 24 array is indexed by the hash function of the key, so each linked list 25 represents all the hash entries with the same hash value. Each HE contains 26 a pointer to the actual value, plus a pointer to a HEK structure which 27 holds the key and hash value. 28 29 =cut 30 31 */ 32 33 #include "EXTERN.h" 34 #define PERL_IN_HV_C 35 #define PERL_HASH_INTERNAL_ACCESS 36 #include "perl.h" 37 38 #define DO_HSPLIT(xhv) ((xhv)->xhv_keys > (xhv)->xhv_max) /* HvTOTALKEYS(hv) > HvMAX(hv) */ 39 #define HV_FILL_THRESHOLD 31 40 41 static const char S_strtab_error[] 42 = "Cannot modify shared string table in hv_%s"; 43 44 #ifdef PURIFY 45 46 #define new_HE() (HE*)safemalloc(sizeof(HE)) 47 #define del_HE(p) safefree((char*)p) 48 49 #else 50 51 STATIC HE* 52 S_new_he(pTHX) 53 { 54 dVAR; 55 HE* he; 56 void ** const root = &PL_body_roots[HE_SVSLOT]; 57 58 if (!*root) 59 Perl_more_bodies(aTHX_ HE_SVSLOT, sizeof(HE), PERL_ARENA_SIZE); 60 he = (HE*) *root; 61 assert(he); 62 *root = HeNEXT(he); 63 return he; 64 } 65 66 #define new_HE() new_he() 67 #define del_HE(p) \ 68 STMT_START { \ 69 HeNEXT(p) = (HE*)(PL_body_roots[HE_SVSLOT]); \ 70 PL_body_roots[HE_SVSLOT] = p; \ 71 } STMT_END 72 73 74 75 #endif 76 77 STATIC HEK * 78 S_save_hek_flags(const char *str, I32 len, U32 hash, int flags) 79 { 80 const int flags_masked = flags & HVhek_MASK; 81 char *k; 82 HEK *hek; 83 84 PERL_ARGS_ASSERT_SAVE_HEK_FLAGS; 85 86 Newx(k, HEK_BASESIZE + len + 2, char); 87 hek = (HEK*)k; 88 Copy(str, HEK_KEY(hek), len, char); 89 HEK_KEY(hek)[len] = 0; 90 HEK_LEN(hek) = len; 91 HEK_HASH(hek) = hash; 92 HEK_FLAGS(hek) = (unsigned char)flags_masked | HVhek_UNSHARED; 93 94 if (flags & HVhek_FREEKEY) 95 Safefree(str); 96 return hek; 97 } 98 99 /* free the pool of temporary HE/HEK pairs returned by hv_fetch_ent 100 * for tied hashes */ 101 102 void 103 Perl_free_tied_hv_pool(pTHX) 104 { 105 dVAR; 106 HE *he = PL_hv_fetch_ent_mh; 107 while (he) { 108 HE * const ohe = he; 109 Safefree(HeKEY_hek(he)); 110 he = HeNEXT(he); 111 del_HE(ohe); 112 } 113 PL_hv_fetch_ent_mh = NULL; 114 } 115 116 #if defined(USE_ITHREADS) 117 HEK * 118 Perl_hek_dup(pTHX_ HEK *source, CLONE_PARAMS* param) 119 { 120 HEK *shared; 121 122 PERL_ARGS_ASSERT_HEK_DUP; 123 PERL_UNUSED_ARG(param); 124 125 if (!source) 126 return NULL; 127 128 shared = (HEK*)ptr_table_fetch(PL_ptr_table, source); 129 if (shared) { 130 /* We already shared this hash key. */ 131 (void)share_hek_hek(shared); 132 } 133 else { 134 shared 135 = share_hek_flags(HEK_KEY(source), HEK_LEN(source), 136 HEK_HASH(source), HEK_FLAGS(source)); 137 ptr_table_store(PL_ptr_table, source, shared); 138 } 139 return shared; 140 } 141 142 HE * 143 Perl_he_dup(pTHX_ const HE *e, bool shared, CLONE_PARAMS* param) 144 { 145 HE *ret; 146 147 PERL_ARGS_ASSERT_HE_DUP; 148 149 if (!e) 150 return NULL; 151 /* look for it in the table first */ 152 ret = (HE*)ptr_table_fetch(PL_ptr_table, e); 153 if (ret) 154 return ret; 155 156 /* create anew and remember what it is */ 157 ret = new_HE(); 158 ptr_table_store(PL_ptr_table, e, ret); 159 160 HeNEXT(ret) = he_dup(HeNEXT(e),shared, param); 161 if (HeKLEN(e) == HEf_SVKEY) { 162 char *k; 163 Newx(k, HEK_BASESIZE + sizeof(const SV *), char); 164 HeKEY_hek(ret) = (HEK*)k; 165 HeKEY_sv(ret) = sv_dup_inc(HeKEY_sv(e), param); 166 } 167 else if (shared) { 168 /* This is hek_dup inlined, which seems to be important for speed 169 reasons. */ 170 HEK * const source = HeKEY_hek(e); 171 HEK *shared = (HEK*)ptr_table_fetch(PL_ptr_table, source); 172 173 if (shared) { 174 /* We already shared this hash key. */ 175 (void)share_hek_hek(shared); 176 } 177 else { 178 shared 179 = share_hek_flags(HEK_KEY(source), HEK_LEN(source), 180 HEK_HASH(source), HEK_FLAGS(source)); 181 ptr_table_store(PL_ptr_table, source, shared); 182 } 183 HeKEY_hek(ret) = shared; 184 } 185 else 186 HeKEY_hek(ret) = save_hek_flags(HeKEY(e), HeKLEN(e), HeHASH(e), 187 HeKFLAGS(e)); 188 HeVAL(ret) = sv_dup_inc(HeVAL(e), param); 189 return ret; 190 } 191 #endif /* USE_ITHREADS */ 192 193 static void 194 S_hv_notallowed(pTHX_ int flags, const char *key, I32 klen, 195 const char *msg) 196 { 197 SV * const sv = sv_newmortal(); 198 199 PERL_ARGS_ASSERT_HV_NOTALLOWED; 200 201 if (!(flags & HVhek_FREEKEY)) { 202 sv_setpvn(sv, key, klen); 203 } 204 else { 205 /* Need to free saved eventually assign to mortal SV */ 206 /* XXX is this line an error ???: SV *sv = sv_newmortal(); */ 207 sv_usepvn(sv, (char *) key, klen); 208 } 209 if (flags & HVhek_UTF8) { 210 SvUTF8_on(sv); 211 } 212 Perl_croak(aTHX_ msg, SVfARG(sv)); 213 } 214 215 /* (klen == HEf_SVKEY) is special for MAGICAL hv entries, meaning key slot 216 * contains an SV* */ 217 218 /* 219 =for apidoc hv_store 220 221 Stores an SV in a hash. The hash key is specified as C<key> and the 222 absolute value of C<klen> is the length of the key. If C<klen> is 223 negative the key is assumed to be in UTF-8-encoded Unicode. The 224 C<hash> parameter is the precomputed hash value; if it is zero then 225 Perl will compute it. 226 227 The return value will be 228 NULL if the operation failed or if the value did not need to be actually 229 stored within the hash (as in the case of tied hashes). Otherwise it can 230 be dereferenced to get the original C<SV*>. Note that the caller is 231 responsible for suitably incrementing the reference count of C<val> before 232 the call, and decrementing it if the function returned NULL. Effectively 233 a successful hv_store takes ownership of one reference to C<val>. This is 234 usually what you want; a newly created SV has a reference count of one, so 235 if all your code does is create SVs then store them in a hash, hv_store 236 will own the only reference to the new SV, and your code doesn't need to do 237 anything further to tidy up. hv_store is not implemented as a call to 238 hv_store_ent, and does not create a temporary SV for the key, so if your 239 key data is not already in SV form then use hv_store in preference to 240 hv_store_ent. 241 242 See L<perlguts/"Understanding the Magic of Tied Hashes and Arrays"> for more 243 information on how to use this function on tied hashes. 244 245 =for apidoc hv_store_ent 246 247 Stores C<val> in a hash. The hash key is specified as C<key>. The C<hash> 248 parameter is the precomputed hash value; if it is zero then Perl will 249 compute it. The return value is the new hash entry so created. It will be 250 NULL if the operation failed or if the value did not need to be actually 251 stored within the hash (as in the case of tied hashes). Otherwise the 252 contents of the return value can be accessed using the C<He?> macros 253 described here. Note that the caller is responsible for suitably 254 incrementing the reference count of C<val> before the call, and 255 decrementing it if the function returned NULL. Effectively a successful 256 hv_store_ent takes ownership of one reference to C<val>. This is 257 usually what you want; a newly created SV has a reference count of one, so 258 if all your code does is create SVs then store them in a hash, hv_store 259 will own the only reference to the new SV, and your code doesn't need to do 260 anything further to tidy up. Note that hv_store_ent only reads the C<key>; 261 unlike C<val> it does not take ownership of it, so maintaining the correct 262 reference count on C<key> is entirely the caller's responsibility. hv_store 263 is not implemented as a call to hv_store_ent, and does not create a temporary 264 SV for the key, so if your key data is not already in SV form then use 265 hv_store in preference to hv_store_ent. 266 267 See L<perlguts/"Understanding the Magic of Tied Hashes and Arrays"> for more 268 information on how to use this function on tied hashes. 269 270 =for apidoc hv_exists 271 272 Returns a boolean indicating whether the specified hash key exists. The 273 absolute value of C<klen> is the length of the key. If C<klen> is 274 negative the key is assumed to be in UTF-8-encoded Unicode. 275 276 =for apidoc hv_fetch 277 278 Returns the SV which corresponds to the specified key in the hash. 279 The absolute value of C<klen> is the length of the key. If C<klen> is 280 negative the key is assumed to be in UTF-8-encoded Unicode. If 281 C<lval> is set then the fetch will be part of a store. This means that if 282 there is no value in the hash associated with the given key, then one is 283 created and a pointer to it is returned. The C<SV*> it points to can be 284 assigned to. But always check that the 285 return value is non-null before dereferencing it to an C<SV*>. 286 287 See L<perlguts/"Understanding the Magic of Tied Hashes and Arrays"> for more 288 information on how to use this function on tied hashes. 289 290 =for apidoc hv_exists_ent 291 292 Returns a boolean indicating whether 293 the specified hash key exists. C<hash> 294 can be a valid precomputed hash value, or 0 to ask for it to be 295 computed. 296 297 =cut 298 */ 299 300 /* returns an HE * structure with the all fields set */ 301 /* note that hent_val will be a mortal sv for MAGICAL hashes */ 302 /* 303 =for apidoc hv_fetch_ent 304 305 Returns the hash entry which corresponds to the specified key in the hash. 306 C<hash> must be a valid precomputed hash number for the given C<key>, or 0 307 if you want the function to compute it. IF C<lval> is set then the fetch 308 will be part of a store. Make sure the return value is non-null before 309 accessing it. The return value when C<hv> is a tied hash is a pointer to a 310 static location, so be sure to make a copy of the structure if you need to 311 store it somewhere. 312 313 See L<perlguts/"Understanding the Magic of Tied Hashes and Arrays"> for more 314 information on how to use this function on tied hashes. 315 316 =cut 317 */ 318 319 /* Common code for hv_delete()/hv_exists()/hv_fetch()/hv_store() */ 320 void * 321 Perl_hv_common_key_len(pTHX_ HV *hv, const char *key, I32 klen_i32, 322 const int action, SV *val, const U32 hash) 323 { 324 STRLEN klen; 325 int flags; 326 327 PERL_ARGS_ASSERT_HV_COMMON_KEY_LEN; 328 329 if (klen_i32 < 0) { 330 klen = -klen_i32; 331 flags = HVhek_UTF8; 332 } else { 333 klen = klen_i32; 334 flags = 0; 335 } 336 return hv_common(hv, NULL, key, klen, flags, action, val, hash); 337 } 338 339 void * 340 Perl_hv_common(pTHX_ HV *hv, SV *keysv, const char *key, STRLEN klen, 341 int flags, int action, SV *val, U32 hash) 342 { 343 dVAR; 344 XPVHV* xhv; 345 HE *entry; 346 HE **oentry; 347 SV *sv; 348 bool is_utf8; 349 int masked_flags; 350 const int return_svp = action & HV_FETCH_JUST_SV; 351 352 if (!hv) 353 return NULL; 354 if (SvTYPE(hv) == (svtype)SVTYPEMASK) 355 return NULL; 356 357 assert(SvTYPE(hv) == SVt_PVHV); 358 359 if (SvSMAGICAL(hv) && SvGMAGICAL(hv) && !(action & HV_DISABLE_UVAR_XKEY)) { 360 MAGIC* mg; 361 if ((mg = mg_find((const SV *)hv, PERL_MAGIC_uvar))) { 362 struct ufuncs * const uf = (struct ufuncs *)mg->mg_ptr; 363 if (uf->uf_set == NULL) { 364 SV* obj = mg->mg_obj; 365 366 if (!keysv) { 367 keysv = newSVpvn_flags(key, klen, SVs_TEMP | 368 ((flags & HVhek_UTF8) 369 ? SVf_UTF8 : 0)); 370 } 371 372 mg->mg_obj = keysv; /* pass key */ 373 uf->uf_index = action; /* pass action */ 374 magic_getuvar(MUTABLE_SV(hv), mg); 375 keysv = mg->mg_obj; /* may have changed */ 376 mg->mg_obj = obj; 377 378 /* If the key may have changed, then we need to invalidate 379 any passed-in computed hash value. */ 380 hash = 0; 381 } 382 } 383 } 384 if (keysv) { 385 if (flags & HVhek_FREEKEY) 386 Safefree(key); 387 key = SvPV_const(keysv, klen); 388 is_utf8 = (SvUTF8(keysv) != 0); 389 if (SvIsCOW_shared_hash(keysv)) { 390 flags = HVhek_KEYCANONICAL | (is_utf8 ? HVhek_UTF8 : 0); 391 } else { 392 flags = is_utf8 ? HVhek_UTF8 : 0; 393 } 394 } else { 395 is_utf8 = ((flags & HVhek_UTF8) ? TRUE : FALSE); 396 } 397 398 if (action & HV_DELETE) { 399 return (void *) hv_delete_common(hv, keysv, key, klen, 400 flags, action, hash); 401 } 402 403 xhv = (XPVHV*)SvANY(hv); 404 if (SvMAGICAL(hv)) { 405 if (SvRMAGICAL(hv) && !(action & (HV_FETCH_ISSTORE|HV_FETCH_ISEXISTS))) { 406 if (mg_find((const SV *)hv, PERL_MAGIC_tied) 407 || SvGMAGICAL((const SV *)hv)) 408 { 409 /* FIXME should be able to skimp on the HE/HEK here when 410 HV_FETCH_JUST_SV is true. */ 411 if (!keysv) { 412 keysv = newSVpvn_utf8(key, klen, is_utf8); 413 } else { 414 keysv = newSVsv(keysv); 415 } 416 sv = sv_newmortal(); 417 mg_copy(MUTABLE_SV(hv), sv, (char *)keysv, HEf_SVKEY); 418 419 /* grab a fake HE/HEK pair from the pool or make a new one */ 420 entry = PL_hv_fetch_ent_mh; 421 if (entry) 422 PL_hv_fetch_ent_mh = HeNEXT(entry); 423 else { 424 char *k; 425 entry = new_HE(); 426 Newx(k, HEK_BASESIZE + sizeof(const SV *), char); 427 HeKEY_hek(entry) = (HEK*)k; 428 } 429 HeNEXT(entry) = NULL; 430 HeSVKEY_set(entry, keysv); 431 HeVAL(entry) = sv; 432 sv_upgrade(sv, SVt_PVLV); 433 LvTYPE(sv) = 'T'; 434 /* so we can free entry when freeing sv */ 435 LvTARG(sv) = MUTABLE_SV(entry); 436 437 /* XXX remove at some point? */ 438 if (flags & HVhek_FREEKEY) 439 Safefree(key); 440 441 if (return_svp) { 442 return entry ? (void *) &HeVAL(entry) : NULL; 443 } 444 return (void *) entry; 445 } 446 #ifdef ENV_IS_CASELESS 447 else if (mg_find((const SV *)hv, PERL_MAGIC_env)) { 448 U32 i; 449 for (i = 0; i < klen; ++i) 450 if (isLOWER(key[i])) { 451 /* Would be nice if we had a routine to do the 452 copy and upercase in a single pass through. */ 453 const char * const nkey = strupr(savepvn(key,klen)); 454 /* Note that this fetch is for nkey (the uppercased 455 key) whereas the store is for key (the original) */ 456 void *result = hv_common(hv, NULL, nkey, klen, 457 HVhek_FREEKEY, /* free nkey */ 458 0 /* non-LVAL fetch */ 459 | HV_DISABLE_UVAR_XKEY 460 | return_svp, 461 NULL /* no value */, 462 0 /* compute hash */); 463 if (!result && (action & HV_FETCH_LVALUE)) { 464 /* This call will free key if necessary. 465 Do it this way to encourage compiler to tail 466 call optimise. */ 467 result = hv_common(hv, keysv, key, klen, flags, 468 HV_FETCH_ISSTORE 469 | HV_DISABLE_UVAR_XKEY 470 | return_svp, 471 newSV(0), hash); 472 } else { 473 if (flags & HVhek_FREEKEY) 474 Safefree(key); 475 } 476 return result; 477 } 478 } 479 #endif 480 } /* ISFETCH */ 481 else if (SvRMAGICAL(hv) && (action & HV_FETCH_ISEXISTS)) { 482 if (mg_find((const SV *)hv, PERL_MAGIC_tied) 483 || SvGMAGICAL((const SV *)hv)) { 484 /* I don't understand why hv_exists_ent has svret and sv, 485 whereas hv_exists only had one. */ 486 SV * const svret = sv_newmortal(); 487 sv = sv_newmortal(); 488 489 if (keysv || is_utf8) { 490 if (!keysv) { 491 keysv = newSVpvn_utf8(key, klen, TRUE); 492 } else { 493 keysv = newSVsv(keysv); 494 } 495 mg_copy(MUTABLE_SV(hv), sv, (char *)sv_2mortal(keysv), HEf_SVKEY); 496 } else { 497 mg_copy(MUTABLE_SV(hv), sv, key, klen); 498 } 499 if (flags & HVhek_FREEKEY) 500 Safefree(key); 501 magic_existspack(svret, mg_find(sv, PERL_MAGIC_tiedelem)); 502 /* This cast somewhat evil, but I'm merely using NULL/ 503 not NULL to return the boolean exists. 504 And I know hv is not NULL. */ 505 return SvTRUE(svret) ? (void *)hv : NULL; 506 } 507 #ifdef ENV_IS_CASELESS 508 else if (mg_find((const SV *)hv, PERL_MAGIC_env)) { 509 /* XXX This code isn't UTF8 clean. */ 510 char * const keysave = (char * const)key; 511 /* Will need to free this, so set FREEKEY flag. */ 512 key = savepvn(key,klen); 513 key = (const char*)strupr((char*)key); 514 is_utf8 = FALSE; 515 hash = 0; 516 keysv = 0; 517 518 if (flags & HVhek_FREEKEY) { 519 Safefree(keysave); 520 } 521 flags |= HVhek_FREEKEY; 522 } 523 #endif 524 } /* ISEXISTS */ 525 else if (action & HV_FETCH_ISSTORE) { 526 bool needs_copy; 527 bool needs_store; 528 hv_magic_check (hv, &needs_copy, &needs_store); 529 if (needs_copy) { 530 const bool save_taint = TAINT_get; 531 if (keysv || is_utf8) { 532 if (!keysv) { 533 keysv = newSVpvn_utf8(key, klen, TRUE); 534 } 535 if (TAINTING_get) 536 TAINT_set(SvTAINTED(keysv)); 537 keysv = sv_2mortal(newSVsv(keysv)); 538 mg_copy(MUTABLE_SV(hv), val, (char*)keysv, HEf_SVKEY); 539 } else { 540 mg_copy(MUTABLE_SV(hv), val, key, klen); 541 } 542 543 TAINT_IF(save_taint); 544 #ifdef NO_TAINT_SUPPORT 545 PERL_UNUSED_VAR(save_taint); 546 #endif 547 if (!needs_store) { 548 if (flags & HVhek_FREEKEY) 549 Safefree(key); 550 return NULL; 551 } 552 #ifdef ENV_IS_CASELESS 553 else if (mg_find((const SV *)hv, PERL_MAGIC_env)) { 554 /* XXX This code isn't UTF8 clean. */ 555 const char *keysave = key; 556 /* Will need to free this, so set FREEKEY flag. */ 557 key = savepvn(key,klen); 558 key = (const char*)strupr((char*)key); 559 is_utf8 = FALSE; 560 hash = 0; 561 keysv = 0; 562 563 if (flags & HVhek_FREEKEY) { 564 Safefree(keysave); 565 } 566 flags |= HVhek_FREEKEY; 567 } 568 #endif 569 } 570 } /* ISSTORE */ 571 } /* SvMAGICAL */ 572 573 if (!HvARRAY(hv)) { 574 if ((action & (HV_FETCH_LVALUE | HV_FETCH_ISSTORE)) 575 #ifdef DYNAMIC_ENV_FETCH /* if it's an %ENV lookup, we may get it on the fly */ 576 || (SvRMAGICAL((const SV *)hv) 577 && mg_find((const SV *)hv, PERL_MAGIC_env)) 578 #endif 579 ) { 580 char *array; 581 Newxz(array, 582 PERL_HV_ARRAY_ALLOC_BYTES(xhv->xhv_max+1 /* HvMAX(hv)+1 */), 583 char); 584 HvARRAY(hv) = (HE**)array; 585 } 586 #ifdef DYNAMIC_ENV_FETCH 587 else if (action & HV_FETCH_ISEXISTS) { 588 /* for an %ENV exists, if we do an insert it's by a recursive 589 store call, so avoid creating HvARRAY(hv) right now. */ 590 } 591 #endif 592 else { 593 /* XXX remove at some point? */ 594 if (flags & HVhek_FREEKEY) 595 Safefree(key); 596 597 return NULL; 598 } 599 } 600 601 if (is_utf8 && !(flags & HVhek_KEYCANONICAL)) { 602 char * const keysave = (char *)key; 603 key = (char*)bytes_from_utf8((U8*)key, &klen, &is_utf8); 604 if (is_utf8) 605 flags |= HVhek_UTF8; 606 else 607 flags &= ~HVhek_UTF8; 608 if (key != keysave) { 609 if (flags & HVhek_FREEKEY) 610 Safefree(keysave); 611 flags |= HVhek_WASUTF8 | HVhek_FREEKEY; 612 /* If the caller calculated a hash, it was on the sequence of 613 octets that are the UTF-8 form. We've now changed the sequence 614 of octets stored to that of the equivalent byte representation, 615 so the hash we need is different. */ 616 hash = 0; 617 } 618 } 619 620 if (!hash) { 621 if (keysv && (SvIsCOW_shared_hash(keysv))) 622 hash = SvSHARED_HASH(keysv); 623 else 624 PERL_HASH(hash, key, klen); 625 } 626 627 masked_flags = (flags & HVhek_MASK); 628 629 #ifdef DYNAMIC_ENV_FETCH 630 if (!HvARRAY(hv)) entry = NULL; 631 else 632 #endif 633 { 634 entry = (HvARRAY(hv))[hash & (I32) HvMAX(hv)]; 635 } 636 for (; entry; entry = HeNEXT(entry)) { 637 if (HeHASH(entry) != hash) /* strings can't be equal */ 638 continue; 639 if (HeKLEN(entry) != (I32)klen) 640 continue; 641 if (HeKEY(entry) != key && memNE(HeKEY(entry),key,klen)) /* is this it? */ 642 continue; 643 if ((HeKFLAGS(entry) ^ masked_flags) & HVhek_UTF8) 644 continue; 645 646 if (action & (HV_FETCH_LVALUE|HV_FETCH_ISSTORE)) { 647 if (HeKFLAGS(entry) != masked_flags) { 648 /* We match if HVhek_UTF8 bit in our flags and hash key's 649 match. But if entry was set previously with HVhek_WASUTF8 650 and key now doesn't (or vice versa) then we should change 651 the key's flag, as this is assignment. */ 652 if (HvSHAREKEYS(hv)) { 653 /* Need to swap the key we have for a key with the flags we 654 need. As keys are shared we can't just write to the 655 flag, so we share the new one, unshare the old one. */ 656 HEK * const new_hek = share_hek_flags(key, klen, hash, 657 masked_flags); 658 unshare_hek (HeKEY_hek(entry)); 659 HeKEY_hek(entry) = new_hek; 660 } 661 else if (hv == PL_strtab) { 662 /* PL_strtab is usually the only hash without HvSHAREKEYS, 663 so putting this test here is cheap */ 664 if (flags & HVhek_FREEKEY) 665 Safefree(key); 666 Perl_croak(aTHX_ S_strtab_error, 667 action & HV_FETCH_LVALUE ? "fetch" : "store"); 668 } 669 else 670 HeKFLAGS(entry) = masked_flags; 671 if (masked_flags & HVhek_ENABLEHVKFLAGS) 672 HvHASKFLAGS_on(hv); 673 } 674 if (HeVAL(entry) == &PL_sv_placeholder) { 675 /* yes, can store into placeholder slot */ 676 if (action & HV_FETCH_LVALUE) { 677 if (SvMAGICAL(hv)) { 678 /* This preserves behaviour with the old hv_fetch 679 implementation which at this point would bail out 680 with a break; (at "if we find a placeholder, we 681 pretend we haven't found anything") 682 683 That break mean that if a placeholder were found, it 684 caused a call into hv_store, which in turn would 685 check magic, and if there is no magic end up pretty 686 much back at this point (in hv_store's code). */ 687 break; 688 } 689 /* LVAL fetch which actually needs a store. */ 690 val = newSV(0); 691 HvPLACEHOLDERS(hv)--; 692 } else { 693 /* store */ 694 if (val != &PL_sv_placeholder) 695 HvPLACEHOLDERS(hv)--; 696 } 697 HeVAL(entry) = val; 698 } else if (action & HV_FETCH_ISSTORE) { 699 SvREFCNT_dec(HeVAL(entry)); 700 HeVAL(entry) = val; 701 } 702 } else if (HeVAL(entry) == &PL_sv_placeholder) { 703 /* if we find a placeholder, we pretend we haven't found 704 anything */ 705 break; 706 } 707 if (flags & HVhek_FREEKEY) 708 Safefree(key); 709 if (return_svp) { 710 return entry ? (void *) &HeVAL(entry) : NULL; 711 } 712 return entry; 713 } 714 #ifdef DYNAMIC_ENV_FETCH /* %ENV lookup? If so, try to fetch the value now */ 715 if (!(action & HV_FETCH_ISSTORE) 716 && SvRMAGICAL((const SV *)hv) 717 && mg_find((const SV *)hv, PERL_MAGIC_env)) { 718 unsigned long len; 719 const char * const env = PerlEnv_ENVgetenv_len(key,&len); 720 if (env) { 721 sv = newSVpvn(env,len); 722 SvTAINTED_on(sv); 723 return hv_common(hv, keysv, key, klen, flags, 724 HV_FETCH_ISSTORE|HV_DISABLE_UVAR_XKEY|return_svp, 725 sv, hash); 726 } 727 } 728 #endif 729 730 if (!entry && SvREADONLY(hv) && !(action & HV_FETCH_ISEXISTS)) { 731 hv_notallowed(flags, key, klen, 732 "Attempt to access disallowed key '%"SVf"' in" 733 " a restricted hash"); 734 } 735 if (!(action & (HV_FETCH_LVALUE|HV_FETCH_ISSTORE))) { 736 /* Not doing some form of store, so return failure. */ 737 if (flags & HVhek_FREEKEY) 738 Safefree(key); 739 return NULL; 740 } 741 if (action & HV_FETCH_LVALUE) { 742 val = action & HV_FETCH_EMPTY_HE ? NULL : newSV(0); 743 if (SvMAGICAL(hv)) { 744 /* At this point the old hv_fetch code would call to hv_store, 745 which in turn might do some tied magic. So we need to make that 746 magic check happen. */ 747 /* gonna assign to this, so it better be there */ 748 /* If a fetch-as-store fails on the fetch, then the action is to 749 recurse once into "hv_store". If we didn't do this, then that 750 recursive call would call the key conversion routine again. 751 However, as we replace the original key with the converted 752 key, this would result in a double conversion, which would show 753 up as a bug if the conversion routine is not idempotent. 754 Hence the use of HV_DISABLE_UVAR_XKEY. */ 755 return hv_common(hv, keysv, key, klen, flags, 756 HV_FETCH_ISSTORE|HV_DISABLE_UVAR_XKEY|return_svp, 757 val, hash); 758 /* XXX Surely that could leak if the fetch-was-store fails? 759 Just like the hv_fetch. */ 760 } 761 } 762 763 /* Welcome to hv_store... */ 764 765 if (!HvARRAY(hv)) { 766 /* Not sure if we can get here. I think the only case of oentry being 767 NULL is for %ENV with dynamic env fetch. But that should disappear 768 with magic in the previous code. */ 769 char *array; 770 Newxz(array, 771 PERL_HV_ARRAY_ALLOC_BYTES(xhv->xhv_max+1 /* HvMAX(hv)+1 */), 772 char); 773 HvARRAY(hv) = (HE**)array; 774 } 775 776 oentry = &(HvARRAY(hv))[hash & (I32) xhv->xhv_max]; 777 778 entry = new_HE(); 779 /* share_hek_flags will do the free for us. This might be considered 780 bad API design. */ 781 if (HvSHAREKEYS(hv)) 782 HeKEY_hek(entry) = share_hek_flags(key, klen, hash, flags); 783 else if (hv == PL_strtab) { 784 /* PL_strtab is usually the only hash without HvSHAREKEYS, so putting 785 this test here is cheap */ 786 if (flags & HVhek_FREEKEY) 787 Safefree(key); 788 Perl_croak(aTHX_ S_strtab_error, 789 action & HV_FETCH_LVALUE ? "fetch" : "store"); 790 } 791 else /* gotta do the real thing */ 792 HeKEY_hek(entry) = save_hek_flags(key, klen, hash, flags); 793 HeVAL(entry) = val; 794 795 if (!*oentry && SvOOK(hv)) { 796 /* initial entry, and aux struct present. */ 797 struct xpvhv_aux *const aux = HvAUX(hv); 798 if (aux->xhv_fill_lazy) 799 ++aux->xhv_fill_lazy; 800 } 801 802 #ifdef PERL_HASH_RANDOMIZE_KEYS 803 /* This logic semi-randomizes the insert order in a bucket. 804 * Either we insert into the top, or the slot below the top, 805 * making it harder to see if there is a collision. We also 806 * reset the iterator randomizer if there is one. 807 */ 808 if ( *oentry && PL_HASH_RAND_BITS_ENABLED) { 809 PL_hash_rand_bits++; 810 PL_hash_rand_bits= ROTL_UV(PL_hash_rand_bits,1); 811 if ( PL_hash_rand_bits & 1 ) { 812 HeNEXT(entry) = HeNEXT(*oentry); 813 HeNEXT(*oentry) = entry; 814 } else { 815 HeNEXT(entry) = *oentry; 816 *oentry = entry; 817 } 818 } else 819 #endif 820 { 821 HeNEXT(entry) = *oentry; 822 *oentry = entry; 823 } 824 #ifdef PERL_HASH_RANDOMIZE_KEYS 825 if (SvOOK(hv)) { 826 /* Currently this makes various tests warn in annoying ways. 827 * So Silenced for now. - Yves | bogus end of comment =>* / 828 if (HvAUX(hv)->xhv_riter != -1) { 829 Perl_ck_warner_d(aTHX_ packWARN(WARN_INTERNAL), 830 "[TESTING] Inserting into a hash during each() traversal results in undefined behavior" 831 pTHX__FORMAT 832 pTHX__VALUE); 833 } 834 */ 835 if (PL_HASH_RAND_BITS_ENABLED) { 836 if (PL_HASH_RAND_BITS_ENABLED == 1) 837 PL_hash_rand_bits += (PTRV)entry + 1; /* we don't bother to use ptr_hash here */ 838 PL_hash_rand_bits= ROTL_UV(PL_hash_rand_bits,1); 839 } 840 HvAUX(hv)->xhv_rand= (U32)PL_hash_rand_bits; 841 } 842 #endif 843 844 if (val == &PL_sv_placeholder) 845 HvPLACEHOLDERS(hv)++; 846 if (masked_flags & HVhek_ENABLEHVKFLAGS) 847 HvHASKFLAGS_on(hv); 848 849 xhv->xhv_keys++; /* HvTOTALKEYS(hv)++ */ 850 if ( DO_HSPLIT(xhv) ) { 851 const STRLEN oldsize = xhv->xhv_max + 1; 852 const U32 items = (U32)HvPLACEHOLDERS_get(hv); 853 854 if (items /* hash has placeholders */ 855 && !SvREADONLY(hv) /* but is not a restricted hash */) { 856 /* If this hash previously was a "restricted hash" and had 857 placeholders, but the "restricted" flag has been turned off, 858 then the placeholders no longer serve any useful purpose. 859 However, they have the downsides of taking up RAM, and adding 860 extra steps when finding used values. It's safe to clear them 861 at this point, even though Storable rebuilds restricted hashes by 862 putting in all the placeholders (first) before turning on the 863 readonly flag, because Storable always pre-splits the hash. 864 If we're lucky, then we may clear sufficient placeholders to 865 avoid needing to split the hash at all. */ 866 clear_placeholders(hv, items); 867 if (DO_HSPLIT(xhv)) 868 hsplit(hv, oldsize, oldsize * 2); 869 } else 870 hsplit(hv, oldsize, oldsize * 2); 871 } 872 873 if (return_svp) { 874 return entry ? (void *) &HeVAL(entry) : NULL; 875 } 876 return (void *) entry; 877 } 878 879 STATIC void 880 S_hv_magic_check(HV *hv, bool *needs_copy, bool *needs_store) 881 { 882 const MAGIC *mg = SvMAGIC(hv); 883 884 PERL_ARGS_ASSERT_HV_MAGIC_CHECK; 885 886 *needs_copy = FALSE; 887 *needs_store = TRUE; 888 while (mg) { 889 if (isUPPER(mg->mg_type)) { 890 *needs_copy = TRUE; 891 if (mg->mg_type == PERL_MAGIC_tied) { 892 *needs_store = FALSE; 893 return; /* We've set all there is to set. */ 894 } 895 } 896 mg = mg->mg_moremagic; 897 } 898 } 899 900 /* 901 =for apidoc hv_scalar 902 903 Evaluates the hash in scalar context and returns the result. Handles magic 904 when the hash is tied. 905 906 =cut 907 */ 908 909 SV * 910 Perl_hv_scalar(pTHX_ HV *hv) 911 { 912 SV *sv; 913 914 PERL_ARGS_ASSERT_HV_SCALAR; 915 916 if (SvRMAGICAL(hv)) { 917 MAGIC * const mg = mg_find((const SV *)hv, PERL_MAGIC_tied); 918 if (mg) 919 return magic_scalarpack(hv, mg); 920 } 921 922 sv = sv_newmortal(); 923 if (HvTOTALKEYS((const HV *)hv)) 924 Perl_sv_setpvf(aTHX_ sv, "%ld/%ld", 925 (long)HvFILL(hv), (long)HvMAX(hv) + 1); 926 else 927 sv_setiv(sv, 0); 928 929 return sv; 930 } 931 932 /* 933 =for apidoc hv_delete 934 935 Deletes a key/value pair in the hash. The value's SV is removed from 936 the hash, made mortal, and returned to the caller. The absolute 937 value of C<klen> is the length of the key. If C<klen> is negative the 938 key is assumed to be in UTF-8-encoded Unicode. The C<flags> value 939 will normally be zero; if set to G_DISCARD then NULL will be returned. 940 NULL will also be returned if the key is not found. 941 942 =for apidoc hv_delete_ent 943 944 Deletes a key/value pair in the hash. The value SV is removed from the hash, 945 made mortal, and returned to the caller. The C<flags> value will normally be 946 zero; if set to G_DISCARD then NULL will be returned. NULL will also be 947 returned if the key is not found. C<hash> can be a valid precomputed hash 948 value, or 0 to ask for it to be computed. 949 950 =cut 951 */ 952 953 STATIC SV * 954 S_hv_delete_common(pTHX_ HV *hv, SV *keysv, const char *key, STRLEN klen, 955 int k_flags, I32 d_flags, U32 hash) 956 { 957 dVAR; 958 XPVHV* xhv; 959 HE *entry; 960 HE **oentry; 961 HE *const *first_entry; 962 bool is_utf8 = (k_flags & HVhek_UTF8) ? TRUE : FALSE; 963 int masked_flags; 964 965 if (SvRMAGICAL(hv)) { 966 bool needs_copy; 967 bool needs_store; 968 hv_magic_check (hv, &needs_copy, &needs_store); 969 970 if (needs_copy) { 971 SV *sv; 972 entry = (HE *) hv_common(hv, keysv, key, klen, 973 k_flags & ~HVhek_FREEKEY, 974 HV_FETCH_LVALUE|HV_DISABLE_UVAR_XKEY, 975 NULL, hash); 976 sv = entry ? HeVAL(entry) : NULL; 977 if (sv) { 978 if (SvMAGICAL(sv)) { 979 mg_clear(sv); 980 } 981 if (!needs_store) { 982 if (mg_find(sv, PERL_MAGIC_tiedelem)) { 983 /* No longer an element */ 984 sv_unmagic(sv, PERL_MAGIC_tiedelem); 985 return sv; 986 } 987 return NULL; /* element cannot be deleted */ 988 } 989 #ifdef ENV_IS_CASELESS 990 else if (mg_find((const SV *)hv, PERL_MAGIC_env)) { 991 /* XXX This code isn't UTF8 clean. */ 992 keysv = newSVpvn_flags(key, klen, SVs_TEMP); 993 if (k_flags & HVhek_FREEKEY) { 994 Safefree(key); 995 } 996 key = strupr(SvPVX(keysv)); 997 is_utf8 = 0; 998 k_flags = 0; 999 hash = 0; 1000 } 1001 #endif 1002 } 1003 } 1004 } 1005 xhv = (XPVHV*)SvANY(hv); 1006 if (!HvARRAY(hv)) 1007 return NULL; 1008 1009 if (is_utf8 && !(k_flags & HVhek_KEYCANONICAL)) { 1010 const char * const keysave = key; 1011 key = (char*)bytes_from_utf8((U8*)key, &klen, &is_utf8); 1012 1013 if (is_utf8) 1014 k_flags |= HVhek_UTF8; 1015 else 1016 k_flags &= ~HVhek_UTF8; 1017 if (key != keysave) { 1018 if (k_flags & HVhek_FREEKEY) { 1019 /* This shouldn't happen if our caller does what we expect, 1020 but strictly the API allows it. */ 1021 Safefree(keysave); 1022 } 1023 k_flags |= HVhek_WASUTF8 | HVhek_FREEKEY; 1024 } 1025 HvHASKFLAGS_on(MUTABLE_SV(hv)); 1026 } 1027 1028 if (!hash) { 1029 if (keysv && (SvIsCOW_shared_hash(keysv))) 1030 hash = SvSHARED_HASH(keysv); 1031 else 1032 PERL_HASH(hash, key, klen); 1033 } 1034 1035 masked_flags = (k_flags & HVhek_MASK); 1036 1037 first_entry = oentry = &(HvARRAY(hv))[hash & (I32) HvMAX(hv)]; 1038 entry = *oentry; 1039 for (; entry; oentry = &HeNEXT(entry), entry = *oentry) { 1040 SV *sv; 1041 U8 mro_changes = 0; /* 1 = isa; 2 = package moved */ 1042 GV *gv = NULL; 1043 HV *stash = NULL; 1044 1045 if (HeHASH(entry) != hash) /* strings can't be equal */ 1046 continue; 1047 if (HeKLEN(entry) != (I32)klen) 1048 continue; 1049 if (HeKEY(entry) != key && memNE(HeKEY(entry),key,klen)) /* is this it? */ 1050 continue; 1051 if ((HeKFLAGS(entry) ^ masked_flags) & HVhek_UTF8) 1052 continue; 1053 1054 if (hv == PL_strtab) { 1055 if (k_flags & HVhek_FREEKEY) 1056 Safefree(key); 1057 Perl_croak(aTHX_ S_strtab_error, "delete"); 1058 } 1059 1060 /* if placeholder is here, it's already been deleted.... */ 1061 if (HeVAL(entry) == &PL_sv_placeholder) { 1062 if (k_flags & HVhek_FREEKEY) 1063 Safefree(key); 1064 return NULL; 1065 } 1066 if (SvREADONLY(hv) && HeVAL(entry) && SvREADONLY(HeVAL(entry))) { 1067 hv_notallowed(k_flags, key, klen, 1068 "Attempt to delete readonly key '%"SVf"' from" 1069 " a restricted hash"); 1070 } 1071 if (k_flags & HVhek_FREEKEY) 1072 Safefree(key); 1073 1074 /* If this is a stash and the key ends with ::, then someone is 1075 * deleting a package. 1076 */ 1077 if (HeVAL(entry) && HvENAME_get(hv)) { 1078 gv = (GV *)HeVAL(entry); 1079 if (keysv) key = SvPV(keysv, klen); 1080 if (( 1081 (klen > 1 && key[klen-2] == ':' && key[klen-1] == ':') 1082 || 1083 (klen == 1 && key[0] == ':') 1084 ) 1085 && (klen != 6 || hv!=PL_defstash || memNE(key,"main::",6)) 1086 && SvTYPE(gv) == SVt_PVGV && (stash = GvHV((GV *)gv)) 1087 && HvENAME_get(stash)) { 1088 /* A previous version of this code checked that the 1089 * GV was still in the symbol table by fetching the 1090 * GV with its name. That is not necessary (and 1091 * sometimes incorrect), as HvENAME cannot be set 1092 * on hv if it is not in the symtab. */ 1093 mro_changes = 2; 1094 /* Hang on to it for a bit. */ 1095 SvREFCNT_inc_simple_void_NN( 1096 sv_2mortal((SV *)gv) 1097 ); 1098 } 1099 else if (klen == 3 && strnEQ(key, "ISA", 3)) 1100 mro_changes = 1; 1101 } 1102 1103 sv = d_flags & G_DISCARD ? HeVAL(entry) : sv_2mortal(HeVAL(entry)); 1104 HeVAL(entry) = &PL_sv_placeholder; 1105 if (sv) { 1106 /* deletion of method from stash */ 1107 if (isGV(sv) && isGV_with_GP(sv) && GvCVu(sv) 1108 && HvENAME_get(hv)) 1109 mro_method_changed_in(hv); 1110 } 1111 1112 /* 1113 * If a restricted hash, rather than really deleting the entry, put 1114 * a placeholder there. This marks the key as being "approved", so 1115 * we can still access via not-really-existing key without raising 1116 * an error. 1117 */ 1118 if (SvREADONLY(hv)) 1119 /* We'll be saving this slot, so the number of allocated keys 1120 * doesn't go down, but the number placeholders goes up */ 1121 HvPLACEHOLDERS(hv)++; 1122 else { 1123 *oentry = HeNEXT(entry); 1124 if(!*first_entry && SvOOK(hv)) { 1125 /* removed last entry, and aux struct present. */ 1126 struct xpvhv_aux *const aux = HvAUX(hv); 1127 if (aux->xhv_fill_lazy) 1128 --aux->xhv_fill_lazy; 1129 } 1130 if (SvOOK(hv) && entry == HvAUX(hv)->xhv_eiter /* HvEITER(hv) */) 1131 HvLAZYDEL_on(hv); 1132 else { 1133 if (SvOOK(hv) && HvLAZYDEL(hv) && 1134 entry == HeNEXT(HvAUX(hv)->xhv_eiter)) 1135 HeNEXT(HvAUX(hv)->xhv_eiter) = HeNEXT(entry); 1136 hv_free_ent(hv, entry); 1137 } 1138 xhv->xhv_keys--; /* HvTOTALKEYS(hv)-- */ 1139 if (xhv->xhv_keys == 0) 1140 HvHASKFLAGS_off(hv); 1141 } 1142 1143 if (d_flags & G_DISCARD) { 1144 SvREFCNT_dec(sv); 1145 sv = NULL; 1146 } 1147 1148 if (mro_changes == 1) mro_isa_changed_in(hv); 1149 else if (mro_changes == 2) 1150 mro_package_moved(NULL, stash, gv, 1); 1151 1152 return sv; 1153 } 1154 if (SvREADONLY(hv)) { 1155 hv_notallowed(k_flags, key, klen, 1156 "Attempt to delete disallowed key '%"SVf"' from" 1157 " a restricted hash"); 1158 } 1159 1160 if (k_flags & HVhek_FREEKEY) 1161 Safefree(key); 1162 return NULL; 1163 } 1164 1165 1166 STATIC void 1167 S_hsplit(pTHX_ HV *hv, STRLEN const oldsize, STRLEN newsize) 1168 { 1169 dVAR; 1170 STRLEN i = 0; 1171 char *a = (char*) HvARRAY(hv); 1172 HE **aep; 1173 1174 bool do_aux= ( 1175 /* already have an HvAUX(hv) so we have to move it */ 1176 SvOOK(hv) || 1177 /* no HvAUX() but array we are going to allocate is large enough 1178 * there is no point in saving the space for the iterator, and 1179 * speeds up later traversals. */ 1180 ( ( hv != PL_strtab ) && ( newsize >= PERL_HV_ALLOC_AUX_SIZE ) ) 1181 ); 1182 1183 PERL_ARGS_ASSERT_HSPLIT; 1184 1185 PL_nomemok = TRUE; 1186 Renew(a, PERL_HV_ARRAY_ALLOC_BYTES(newsize) 1187 + (do_aux ? sizeof(struct xpvhv_aux) : 0), char); 1188 PL_nomemok = FALSE; 1189 if (!a) { 1190 return; 1191 } 1192 1193 #ifdef PERL_HASH_RANDOMIZE_KEYS 1194 /* the idea of this is that we create a "random" value by hashing the address of 1195 * the array, we then use the low bit to decide if we insert at the top, or insert 1196 * second from top. After each such insert we rotate the hashed value. So we can 1197 * use the same hashed value over and over, and in normal build environments use 1198 * very few ops to do so. ROTL32() should produce a single machine operation. */ 1199 if (PL_HASH_RAND_BITS_ENABLED) { 1200 if (PL_HASH_RAND_BITS_ENABLED == 1) 1201 PL_hash_rand_bits += ptr_hash((PTRV)a); 1202 PL_hash_rand_bits = ROTL_UV(PL_hash_rand_bits,1); 1203 } 1204 #endif 1205 HvARRAY(hv) = (HE**) a; 1206 HvMAX(hv) = newsize - 1; 1207 /* before we zero the newly added memory, we 1208 * need to deal with the aux struct that may be there 1209 * or have been allocated by us*/ 1210 if (do_aux) { 1211 struct xpvhv_aux *const dest 1212 = (struct xpvhv_aux*) &a[newsize * sizeof(HE*)]; 1213 if (SvOOK(hv)) { 1214 /* alread have an aux, copy the old one in place. */ 1215 Move(&a[oldsize * sizeof(HE*)], dest, 1, struct xpvhv_aux); 1216 /* we reset the iterator's xhv_rand as well, so they get a totally new ordering */ 1217 #ifdef PERL_HASH_RANDOMIZE_KEYS 1218 dest->xhv_rand = (U32)PL_hash_rand_bits; 1219 #endif 1220 /* For now, just reset the lazy fill counter. 1221 It would be possible to update the counter in the code below 1222 instead. */ 1223 dest->xhv_fill_lazy = 0; 1224 } else { 1225 /* no existing aux structure, but we allocated space for one 1226 * so intialize it properly. This unrolls hv_auxinit() a bit, 1227 * since we have to do the realloc anyway. */ 1228 /* first we set the iterator's xhv_rand so it can be copied into lastrand below */ 1229 #ifdef PERL_HASH_RANDOMIZE_KEYS 1230 dest->xhv_rand = (U32)PL_hash_rand_bits; 1231 #endif 1232 /* this is the "non realloc" part of the hv_auxinit() */ 1233 (void)hv_auxinit_internal(dest); 1234 /* Turn on the OOK flag */ 1235 SvOOK_on(hv); 1236 } 1237 } 1238 /* now we can safely clear the second half */ 1239 Zero(&a[oldsize * sizeof(HE*)], (newsize-oldsize) * sizeof(HE*), char); /* zero 2nd half*/ 1240 1241 if (!HvTOTALKEYS(hv)) /* skip rest if no entries */ 1242 return; 1243 1244 newsize--; 1245 aep = (HE**)a; 1246 do { 1247 HE **oentry = aep + i; 1248 HE *entry = aep[i]; 1249 1250 if (!entry) /* non-existent */ 1251 continue; 1252 do { 1253 U32 j = (HeHASH(entry) & newsize); 1254 if (j != (U32)i) { 1255 *oentry = HeNEXT(entry); 1256 #ifdef PERL_HASH_RANDOMIZE_KEYS 1257 /* if the target cell is empty or PL_HASH_RAND_BITS_ENABLED is false 1258 * insert to top, otherwise rotate the bucket rand 1 bit, 1259 * and use the new low bit to decide if we insert at top, 1260 * or next from top. IOW, we only rotate on a collision.*/ 1261 if (aep[j] && PL_HASH_RAND_BITS_ENABLED) { 1262 PL_hash_rand_bits+= ROTL_UV(HeHASH(entry), 17); 1263 PL_hash_rand_bits= ROTL_UV(PL_hash_rand_bits,1); 1264 if (PL_hash_rand_bits & 1) { 1265 HeNEXT(entry)= HeNEXT(aep[j]); 1266 HeNEXT(aep[j])= entry; 1267 } else { 1268 /* Note, this is structured in such a way as the optimizer 1269 * should eliminate the duplicated code here and below without 1270 * us needing to explicitly use a goto. */ 1271 HeNEXT(entry) = aep[j]; 1272 aep[j] = entry; 1273 } 1274 } else 1275 #endif 1276 { 1277 /* see comment above about duplicated code */ 1278 HeNEXT(entry) = aep[j]; 1279 aep[j] = entry; 1280 } 1281 } 1282 else { 1283 oentry = &HeNEXT(entry); 1284 } 1285 entry = *oentry; 1286 } while (entry); 1287 } while (i++ < oldsize); 1288 } 1289 1290 void 1291 Perl_hv_ksplit(pTHX_ HV *hv, IV newmax) 1292 { 1293 dVAR; 1294 XPVHV* xhv = (XPVHV*)SvANY(hv); 1295 const I32 oldsize = (I32) xhv->xhv_max+1; /* HvMAX(hv)+1 (sick) */ 1296 I32 newsize; 1297 char *a; 1298 1299 PERL_ARGS_ASSERT_HV_KSPLIT; 1300 1301 newsize = (I32) newmax; /* possible truncation here */ 1302 if (newsize != newmax || newmax <= oldsize) 1303 return; 1304 while ((newsize & (1 + ~newsize)) != newsize) { 1305 newsize &= ~(newsize & (1 + ~newsize)); /* get proper power of 2 */ 1306 } 1307 if (newsize < newmax) 1308 newsize *= 2; 1309 if (newsize < newmax) 1310 return; /* overflow detection */ 1311 1312 a = (char *) HvARRAY(hv); 1313 if (a) { 1314 hsplit(hv, oldsize, newsize); 1315 } else { 1316 Newxz(a, PERL_HV_ARRAY_ALLOC_BYTES(newsize), char); 1317 xhv->xhv_max = --newsize; 1318 HvARRAY(hv) = (HE **) a; 1319 } 1320 } 1321 1322 /* IMO this should also handle cases where hv_max is smaller than hv_keys 1323 * as tied hashes could play silly buggers and mess us around. We will 1324 * do the right thing during hv_store() afterwards, but still - Yves */ 1325 #define HV_SET_MAX_ADJUSTED_FOR_KEYS(hv,hv_max,hv_keys) STMT_START {\ 1326 /* Can we use fewer buckets? (hv_max is always 2^n-1) */ \ 1327 if (hv_max < PERL_HASH_DEFAULT_HvMAX) { \ 1328 hv_max = PERL_HASH_DEFAULT_HvMAX; \ 1329 } else { \ 1330 while (hv_max > PERL_HASH_DEFAULT_HvMAX && hv_max + 1 >= hv_keys * 2) \ 1331 hv_max = hv_max / 2; \ 1332 } \ 1333 HvMAX(hv) = hv_max; \ 1334 } STMT_END 1335 1336 1337 HV * 1338 Perl_newHVhv(pTHX_ HV *ohv) 1339 { 1340 dVAR; 1341 HV * const hv = newHV(); 1342 STRLEN hv_max; 1343 1344 if (!ohv || (!HvTOTALKEYS(ohv) && !SvMAGICAL((const SV *)ohv))) 1345 return hv; 1346 hv_max = HvMAX(ohv); 1347 1348 if (!SvMAGICAL((const SV *)ohv)) { 1349 /* It's an ordinary hash, so copy it fast. AMS 20010804 */ 1350 STRLEN i; 1351 const bool shared = !!HvSHAREKEYS(ohv); 1352 HE **ents, ** const oents = (HE **)HvARRAY(ohv); 1353 char *a; 1354 Newx(a, PERL_HV_ARRAY_ALLOC_BYTES(hv_max+1), char); 1355 ents = (HE**)a; 1356 1357 /* In each bucket... */ 1358 for (i = 0; i <= hv_max; i++) { 1359 HE *prev = NULL; 1360 HE *oent = oents[i]; 1361 1362 if (!oent) { 1363 ents[i] = NULL; 1364 continue; 1365 } 1366 1367 /* Copy the linked list of entries. */ 1368 for (; oent; oent = HeNEXT(oent)) { 1369 const U32 hash = HeHASH(oent); 1370 const char * const key = HeKEY(oent); 1371 const STRLEN len = HeKLEN(oent); 1372 const int flags = HeKFLAGS(oent); 1373 HE * const ent = new_HE(); 1374 SV *const val = HeVAL(oent); 1375 1376 HeVAL(ent) = SvIMMORTAL(val) ? val : newSVsv(val); 1377 HeKEY_hek(ent) 1378 = shared ? share_hek_flags(key, len, hash, flags) 1379 : save_hek_flags(key, len, hash, flags); 1380 if (prev) 1381 HeNEXT(prev) = ent; 1382 else 1383 ents[i] = ent; 1384 prev = ent; 1385 HeNEXT(ent) = NULL; 1386 } 1387 } 1388 1389 HvMAX(hv) = hv_max; 1390 HvTOTALKEYS(hv) = HvTOTALKEYS(ohv); 1391 HvARRAY(hv) = ents; 1392 } /* not magical */ 1393 else { 1394 /* Iterate over ohv, copying keys and values one at a time. */ 1395 HE *entry; 1396 const I32 riter = HvRITER_get(ohv); 1397 HE * const eiter = HvEITER_get(ohv); 1398 STRLEN hv_keys = HvTOTALKEYS(ohv); 1399 1400 HV_SET_MAX_ADJUSTED_FOR_KEYS(hv,hv_max,hv_keys); 1401 1402 hv_iterinit(ohv); 1403 while ((entry = hv_iternext_flags(ohv, 0))) { 1404 SV *val = hv_iterval(ohv,entry); 1405 SV * const keysv = HeSVKEY(entry); 1406 val = SvIMMORTAL(val) ? val : newSVsv(val); 1407 if (keysv) 1408 (void)hv_store_ent(hv, keysv, val, 0); 1409 else 1410 (void)hv_store_flags(hv, HeKEY(entry), HeKLEN(entry), val, 1411 HeHASH(entry), HeKFLAGS(entry)); 1412 } 1413 HvRITER_set(ohv, riter); 1414 HvEITER_set(ohv, eiter); 1415 } 1416 1417 return hv; 1418 } 1419 1420 /* 1421 =for apidoc Am|HV *|hv_copy_hints_hv|HV *ohv 1422 1423 A specialised version of L</newHVhv> for copying C<%^H>. I<ohv> must be 1424 a pointer to a hash (which may have C<%^H> magic, but should be generally 1425 non-magical), or C<NULL> (interpreted as an empty hash). The content 1426 of I<ohv> is copied to a new hash, which has the C<%^H>-specific magic 1427 added to it. A pointer to the new hash is returned. 1428 1429 =cut 1430 */ 1431 1432 HV * 1433 Perl_hv_copy_hints_hv(pTHX_ HV *const ohv) 1434 { 1435 HV * const hv = newHV(); 1436 1437 if (ohv) { 1438 STRLEN hv_max = HvMAX(ohv); 1439 STRLEN hv_keys = HvTOTALKEYS(ohv); 1440 HE *entry; 1441 const I32 riter = HvRITER_get(ohv); 1442 HE * const eiter = HvEITER_get(ohv); 1443 1444 ENTER; 1445 SAVEFREESV(hv); 1446 1447 HV_SET_MAX_ADJUSTED_FOR_KEYS(hv,hv_max,hv_keys); 1448 1449 hv_iterinit(ohv); 1450 while ((entry = hv_iternext_flags(ohv, 0))) { 1451 SV *const sv = newSVsv(hv_iterval(ohv,entry)); 1452 SV *heksv = HeSVKEY(entry); 1453 if (!heksv && sv) heksv = newSVhek(HeKEY_hek(entry)); 1454 if (sv) sv_magic(sv, NULL, PERL_MAGIC_hintselem, 1455 (char *)heksv, HEf_SVKEY); 1456 if (heksv == HeSVKEY(entry)) 1457 (void)hv_store_ent(hv, heksv, sv, 0); 1458 else { 1459 (void)hv_common(hv, heksv, HeKEY(entry), HeKLEN(entry), 1460 HeKFLAGS(entry), HV_FETCH_ISSTORE|HV_FETCH_JUST_SV, sv, HeHASH(entry)); 1461 SvREFCNT_dec_NN(heksv); 1462 } 1463 } 1464 HvRITER_set(ohv, riter); 1465 HvEITER_set(ohv, eiter); 1466 1467 SvREFCNT_inc_simple_void_NN(hv); 1468 LEAVE; 1469 } 1470 hv_magic(hv, NULL, PERL_MAGIC_hints); 1471 return hv; 1472 } 1473 #undef HV_SET_MAX_ADJUSTED_FOR_KEYS 1474 1475 /* like hv_free_ent, but returns the SV rather than freeing it */ 1476 STATIC SV* 1477 S_hv_free_ent_ret(pTHX_ HV *hv, HE *entry) 1478 { 1479 dVAR; 1480 SV *val; 1481 1482 PERL_ARGS_ASSERT_HV_FREE_ENT_RET; 1483 1484 val = HeVAL(entry); 1485 if (HeKLEN(entry) == HEf_SVKEY) { 1486 SvREFCNT_dec(HeKEY_sv(entry)); 1487 Safefree(HeKEY_hek(entry)); 1488 } 1489 else if (HvSHAREKEYS(hv)) 1490 unshare_hek(HeKEY_hek(entry)); 1491 else 1492 Safefree(HeKEY_hek(entry)); 1493 del_HE(entry); 1494 return val; 1495 } 1496 1497 1498 void 1499 Perl_hv_free_ent(pTHX_ HV *hv, HE *entry) 1500 { 1501 dVAR; 1502 SV *val; 1503 1504 PERL_ARGS_ASSERT_HV_FREE_ENT; 1505 1506 if (!entry) 1507 return; 1508 val = hv_free_ent_ret(hv, entry); 1509 SvREFCNT_dec(val); 1510 } 1511 1512 1513 void 1514 Perl_hv_delayfree_ent(pTHX_ HV *hv, HE *entry) 1515 { 1516 dVAR; 1517 1518 PERL_ARGS_ASSERT_HV_DELAYFREE_ENT; 1519 1520 if (!entry) 1521 return; 1522 /* SvREFCNT_inc to counter the SvREFCNT_dec in hv_free_ent */ 1523 sv_2mortal(SvREFCNT_inc(HeVAL(entry))); /* free between statements */ 1524 if (HeKLEN(entry) == HEf_SVKEY) { 1525 sv_2mortal(SvREFCNT_inc(HeKEY_sv(entry))); 1526 } 1527 hv_free_ent(hv, entry); 1528 } 1529 1530 /* 1531 =for apidoc hv_clear 1532 1533 Frees the all the elements of a hash, leaving it empty. 1534 The XS equivalent of C<%hash = ()>. See also L</hv_undef>. 1535 1536 If any destructors are triggered as a result, the hv itself may 1537 be freed. 1538 1539 =cut 1540 */ 1541 1542 void 1543 Perl_hv_clear(pTHX_ HV *hv) 1544 { 1545 dVAR; 1546 XPVHV* xhv; 1547 if (!hv) 1548 return; 1549 1550 DEBUG_A(Perl_hv_assert(aTHX_ hv)); 1551 1552 xhv = (XPVHV*)SvANY(hv); 1553 1554 ENTER; 1555 SAVEFREESV(SvREFCNT_inc_simple_NN(hv)); 1556 if (SvREADONLY(hv) && HvARRAY(hv) != NULL) { 1557 /* restricted hash: convert all keys to placeholders */ 1558 STRLEN i; 1559 for (i = 0; i <= xhv->xhv_max; i++) { 1560 HE *entry = (HvARRAY(hv))[i]; 1561 for (; entry; entry = HeNEXT(entry)) { 1562 /* not already placeholder */ 1563 if (HeVAL(entry) != &PL_sv_placeholder) { 1564 if (HeVAL(entry)) { 1565 if (SvREADONLY(HeVAL(entry))) { 1566 SV* const keysv = hv_iterkeysv(entry); 1567 Perl_croak_nocontext( 1568 "Attempt to delete readonly key '%"SVf"' from a restricted hash", 1569 (void*)keysv); 1570 } 1571 SvREFCNT_dec_NN(HeVAL(entry)); 1572 } 1573 HeVAL(entry) = &PL_sv_placeholder; 1574 HvPLACEHOLDERS(hv)++; 1575 } 1576 } 1577 } 1578 } 1579 else { 1580 hfreeentries(hv); 1581 HvPLACEHOLDERS_set(hv, 0); 1582 1583 if (SvRMAGICAL(hv)) 1584 mg_clear(MUTABLE_SV(hv)); 1585 1586 HvHASKFLAGS_off(hv); 1587 } 1588 if (SvOOK(hv)) { 1589 if(HvENAME_get(hv)) 1590 mro_isa_changed_in(hv); 1591 HvEITER_set(hv, NULL); 1592 } 1593 LEAVE; 1594 } 1595 1596 /* 1597 =for apidoc hv_clear_placeholders 1598 1599 Clears any placeholders from a hash. If a restricted hash has any of its keys 1600 marked as readonly and the key is subsequently deleted, the key is not actually 1601 deleted but is marked by assigning it a value of &PL_sv_placeholder. This tags 1602 it so it will be ignored by future operations such as iterating over the hash, 1603 but will still allow the hash to have a value reassigned to the key at some 1604 future point. This function clears any such placeholder keys from the hash. 1605 See Hash::Util::lock_keys() for an example of its use. 1606 1607 =cut 1608 */ 1609 1610 void 1611 Perl_hv_clear_placeholders(pTHX_ HV *hv) 1612 { 1613 dVAR; 1614 const U32 items = (U32)HvPLACEHOLDERS_get(hv); 1615 1616 PERL_ARGS_ASSERT_HV_CLEAR_PLACEHOLDERS; 1617 1618 if (items) 1619 clear_placeholders(hv, items); 1620 } 1621 1622 static void 1623 S_clear_placeholders(pTHX_ HV *hv, U32 items) 1624 { 1625 dVAR; 1626 I32 i; 1627 1628 PERL_ARGS_ASSERT_CLEAR_PLACEHOLDERS; 1629 1630 if (items == 0) 1631 return; 1632 1633 i = HvMAX(hv); 1634 do { 1635 /* Loop down the linked list heads */ 1636 HE **oentry = &(HvARRAY(hv))[i]; 1637 HE *entry; 1638 1639 while ((entry = *oentry)) { 1640 if (HeVAL(entry) == &PL_sv_placeholder) { 1641 *oentry = HeNEXT(entry); 1642 if (entry == HvEITER_get(hv)) 1643 HvLAZYDEL_on(hv); 1644 else { 1645 if (SvOOK(hv) && HvLAZYDEL(hv) && 1646 entry == HeNEXT(HvAUX(hv)->xhv_eiter)) 1647 HeNEXT(HvAUX(hv)->xhv_eiter) = HeNEXT(entry); 1648 hv_free_ent(hv, entry); 1649 } 1650 1651 if (--items == 0) { 1652 /* Finished. */ 1653 I32 placeholders = HvPLACEHOLDERS_get(hv); 1654 HvTOTALKEYS(hv) -= (IV)placeholders; 1655 /* HvUSEDKEYS expanded */ 1656 if ((HvTOTALKEYS(hv) - placeholders) == 0) 1657 HvHASKFLAGS_off(hv); 1658 HvPLACEHOLDERS_set(hv, 0); 1659 return; 1660 } 1661 } else { 1662 oentry = &HeNEXT(entry); 1663 } 1664 } 1665 } while (--i >= 0); 1666 /* You can't get here, hence assertion should always fail. */ 1667 assert (items == 0); 1668 NOT_REACHED; 1669 } 1670 1671 STATIC void 1672 S_hfreeentries(pTHX_ HV *hv) 1673 { 1674 STRLEN index = 0; 1675 XPVHV * const xhv = (XPVHV*)SvANY(hv); 1676 SV *sv; 1677 1678 PERL_ARGS_ASSERT_HFREEENTRIES; 1679 1680 while ((sv = Perl_hfree_next_entry(aTHX_ hv, &index))||xhv->xhv_keys) { 1681 SvREFCNT_dec(sv); 1682 } 1683 } 1684 1685 1686 /* hfree_next_entry() 1687 * For use only by S_hfreeentries() and sv_clear(). 1688 * Delete the next available HE from hv and return the associated SV. 1689 * Returns null on empty hash. Nevertheless null is not a reliable 1690 * indicator that the hash is empty, as the deleted entry may have a 1691 * null value. 1692 * indexp is a pointer to the current index into HvARRAY. The index should 1693 * initially be set to 0. hfree_next_entry() may update it. */ 1694 1695 SV* 1696 Perl_hfree_next_entry(pTHX_ HV *hv, STRLEN *indexp) 1697 { 1698 struct xpvhv_aux *iter; 1699 HE *entry; 1700 HE ** array; 1701 #ifdef DEBUGGING 1702 STRLEN orig_index = *indexp; 1703 #endif 1704 1705 PERL_ARGS_ASSERT_HFREE_NEXT_ENTRY; 1706 1707 if (SvOOK(hv) && ((iter = HvAUX(hv)))) { 1708 if ((entry = iter->xhv_eiter)) { 1709 /* the iterator may get resurrected after each 1710 * destructor call, so check each time */ 1711 if (entry && HvLAZYDEL(hv)) { /* was deleted earlier? */ 1712 HvLAZYDEL_off(hv); 1713 hv_free_ent(hv, entry); 1714 /* warning: at this point HvARRAY may have been 1715 * re-allocated, HvMAX changed etc */ 1716 } 1717 iter = HvAUX(hv); /* may have been realloced */ 1718 iter->xhv_riter = -1; /* HvRITER(hv) = -1 */ 1719 iter->xhv_eiter = NULL; /* HvEITER(hv) = NULL */ 1720 #ifdef PERL_HASH_RANDOMIZE_KEYS 1721 iter->xhv_last_rand = iter->xhv_rand; 1722 #endif 1723 } 1724 /* Reset any cached HvFILL() to "unknown". It's unlikely that anyone 1725 will actually call HvFILL() on a hash under destruction, so it 1726 seems pointless attempting to track the number of keys remaining. 1727 But if they do, we want to reset it again. */ 1728 if (iter->xhv_fill_lazy) 1729 iter->xhv_fill_lazy = 0; 1730 } 1731 1732 if (!((XPVHV*)SvANY(hv))->xhv_keys) 1733 return NULL; 1734 1735 array = HvARRAY(hv); 1736 assert(array); 1737 while ( ! ((entry = array[*indexp])) ) { 1738 if ((*indexp)++ >= HvMAX(hv)) 1739 *indexp = 0; 1740 assert(*indexp != orig_index); 1741 } 1742 array[*indexp] = HeNEXT(entry); 1743 ((XPVHV*) SvANY(hv))->xhv_keys--; 1744 1745 if ( PL_phase != PERL_PHASE_DESTRUCT && HvENAME(hv) 1746 && HeVAL(entry) && isGV(HeVAL(entry)) 1747 && GvHV(HeVAL(entry)) && HvENAME(GvHV(HeVAL(entry))) 1748 ) { 1749 STRLEN klen; 1750 const char * const key = HePV(entry,klen); 1751 if ((klen > 1 && key[klen-1]==':' && key[klen-2]==':') 1752 || (klen == 1 && key[0] == ':')) { 1753 mro_package_moved( 1754 NULL, GvHV(HeVAL(entry)), 1755 (GV *)HeVAL(entry), 0 1756 ); 1757 } 1758 } 1759 return hv_free_ent_ret(hv, entry); 1760 } 1761 1762 1763 /* 1764 =for apidoc hv_undef 1765 1766 Undefines the hash. The XS equivalent of C<undef(%hash)>. 1767 1768 As well as freeing all the elements of the hash (like hv_clear()), this 1769 also frees any auxiliary data and storage associated with the hash. 1770 1771 If any destructors are triggered as a result, the hv itself may 1772 be freed. 1773 1774 See also L</hv_clear>. 1775 1776 =cut 1777 */ 1778 1779 void 1780 Perl_hv_undef_flags(pTHX_ HV *hv, U32 flags) 1781 { 1782 dVAR; 1783 XPVHV* xhv; 1784 bool save; 1785 1786 if (!hv) 1787 return; 1788 save = !!SvREFCNT(hv); 1789 DEBUG_A(Perl_hv_assert(aTHX_ hv)); 1790 xhv = (XPVHV*)SvANY(hv); 1791 1792 /* The name must be deleted before the call to hfreeeeentries so that 1793 CVs are anonymised properly. But the effective name must be pre- 1794 served until after that call (and only deleted afterwards if the 1795 call originated from sv_clear). For stashes with one name that is 1796 both the canonical name and the effective name, hv_name_set has to 1797 allocate an array for storing the effective name. We can skip that 1798 during global destruction, as it does not matter where the CVs point 1799 if they will be freed anyway. */ 1800 /* note that the code following prior to hfreeentries is duplicated 1801 * in sv_clear(), and changes here should be done there too */ 1802 if (PL_phase != PERL_PHASE_DESTRUCT && HvNAME(hv)) { 1803 if (PL_stashcache) { 1804 DEBUG_o(Perl_deb(aTHX_ "hv_undef_flags clearing PL_stashcache for '%" 1805 HEKf"'\n", HvNAME_HEK(hv))); 1806 (void)hv_deletehek(PL_stashcache, HvNAME_HEK(hv), G_DISCARD); 1807 } 1808 hv_name_set(hv, NULL, 0, 0); 1809 } 1810 if (save) { 1811 ENTER; 1812 SAVEFREESV(SvREFCNT_inc_simple_NN(hv)); 1813 } 1814 hfreeentries(hv); 1815 if (SvOOK(hv)) { 1816 struct mro_meta *meta; 1817 const char *name; 1818 1819 if (HvENAME_get(hv)) { 1820 if (PL_phase != PERL_PHASE_DESTRUCT) 1821 mro_isa_changed_in(hv); 1822 if (PL_stashcache) { 1823 DEBUG_o(Perl_deb(aTHX_ "hv_undef_flags clearing PL_stashcache for effective name '%" 1824 HEKf"'\n", HvENAME_HEK(hv))); 1825 (void)hv_deletehek(PL_stashcache, HvENAME_HEK(hv), G_DISCARD); 1826 } 1827 } 1828 1829 /* If this call originated from sv_clear, then we must check for 1830 * effective names that need freeing, as well as the usual name. */ 1831 name = HvNAME(hv); 1832 if (flags & HV_NAME_SETALL ? !!HvAUX(hv)->xhv_name_u.xhvnameu_name : !!name) { 1833 if (name && PL_stashcache) { 1834 DEBUG_o(Perl_deb(aTHX_ "hv_undef_flags clearing PL_stashcache for name '%" 1835 HEKf"'\n", HvNAME_HEK(hv))); 1836 (void)hv_deletehek(PL_stashcache, HvNAME_HEK(hv), G_DISCARD); 1837 } 1838 hv_name_set(hv, NULL, 0, flags); 1839 } 1840 if((meta = HvAUX(hv)->xhv_mro_meta)) { 1841 if (meta->mro_linear_all) { 1842 SvREFCNT_dec_NN(meta->mro_linear_all); 1843 /* mro_linear_current is just acting as a shortcut pointer, 1844 hence the else. */ 1845 } 1846 else 1847 /* Only the current MRO is stored, so this owns the data. 1848 */ 1849 SvREFCNT_dec(meta->mro_linear_current); 1850 SvREFCNT_dec(meta->mro_nextmethod); 1851 SvREFCNT_dec(meta->isa); 1852 SvREFCNT_dec(meta->super); 1853 Safefree(meta); 1854 HvAUX(hv)->xhv_mro_meta = NULL; 1855 } 1856 if (!HvAUX(hv)->xhv_name_u.xhvnameu_name && ! HvAUX(hv)->xhv_backreferences) 1857 SvFLAGS(hv) &= ~SVf_OOK; 1858 } 1859 if (!SvOOK(hv)) { 1860 Safefree(HvARRAY(hv)); 1861 xhv->xhv_max = PERL_HASH_DEFAULT_HvMAX; /* HvMAX(hv) = 7 (it's a normal hash) */ 1862 HvARRAY(hv) = 0; 1863 } 1864 /* if we're freeing the HV, the SvMAGIC field has been reused for 1865 * other purposes, and so there can't be any placeholder magic */ 1866 if (SvREFCNT(hv)) 1867 HvPLACEHOLDERS_set(hv, 0); 1868 1869 if (SvRMAGICAL(hv)) 1870 mg_clear(MUTABLE_SV(hv)); 1871 if (save) LEAVE; 1872 } 1873 1874 /* 1875 =for apidoc hv_fill 1876 1877 Returns the number of hash buckets that 1878 happen to be in use. This function is 1879 wrapped by the macro C<HvFILL>. 1880 1881 Previously this value was always stored in the HV structure, which created an 1882 overhead on every hash (and pretty much every object) for something that was 1883 rarely used. Now we calculate it on demand the first 1884 time that it is needed, and cache it if that calculation 1885 is going to be costly to repeat. The cached 1886 value is updated by insertions and deletions, but (currently) discarded if 1887 the hash is split. 1888 1889 =cut 1890 */ 1891 1892 STRLEN 1893 Perl_hv_fill(pTHX_ HV *const hv) 1894 { 1895 STRLEN count = 0; 1896 HE **ents = HvARRAY(hv); 1897 struct xpvhv_aux *aux = SvOOK(hv) ? HvAUX(hv) : NULL; 1898 1899 PERL_ARGS_ASSERT_HV_FILL; 1900 1901 /* No keys implies no buckets used. 1902 One key can only possibly mean one bucket used. */ 1903 if (HvTOTALKEYS(hv) < 2) 1904 return HvTOTALKEYS(hv); 1905 1906 #ifndef DEBUGGING 1907 if (aux && aux->xhv_fill_lazy) 1908 return aux->xhv_fill_lazy; 1909 #endif 1910 1911 if (ents) { 1912 HE *const *const last = ents + HvMAX(hv); 1913 count = last + 1 - ents; 1914 1915 do { 1916 if (!*ents) 1917 --count; 1918 } while (++ents <= last); 1919 } 1920 if (aux) { 1921 #ifdef DEBUGGING 1922 if (aux->xhv_fill_lazy) 1923 assert(aux->xhv_fill_lazy == count); 1924 #endif 1925 aux->xhv_fill_lazy = count; 1926 } else if (HvMAX(hv) >= HV_FILL_THRESHOLD) { 1927 aux = hv_auxinit(hv); 1928 aux->xhv_fill_lazy = count; 1929 } 1930 return count; 1931 } 1932 1933 /* hash a pointer to a U32 - Used in the hash traversal randomization 1934 * and bucket order randomization code 1935 * 1936 * this code was derived from Sereal, which was derived from autobox. 1937 */ 1938 1939 PERL_STATIC_INLINE U32 S_ptr_hash(PTRV u) { 1940 #if PTRSIZE == 8 1941 /* 1942 * This is one of Thomas Wang's hash functions for 64-bit integers from: 1943 * http://www.concentric.net/~Ttwang/tech/inthash.htm 1944 */ 1945 u = (~u) + (u << 18); 1946 u = u ^ (u >> 31); 1947 u = u * 21; 1948 u = u ^ (u >> 11); 1949 u = u + (u << 6); 1950 u = u ^ (u >> 22); 1951 #else 1952 /* 1953 * This is one of Bob Jenkins' hash functions for 32-bit integers 1954 * from: http://burtleburtle.net/bob/hash/integer.html 1955 */ 1956 u = (u + 0x7ed55d16) + (u << 12); 1957 u = (u ^ 0xc761c23c) ^ (u >> 19); 1958 u = (u + 0x165667b1) + (u << 5); 1959 u = (u + 0xd3a2646c) ^ (u << 9); 1960 u = (u + 0xfd7046c5) + (u << 3); 1961 u = (u ^ 0xb55a4f09) ^ (u >> 16); 1962 #endif 1963 return (U32)u; 1964 } 1965 1966 static struct xpvhv_aux* 1967 S_hv_auxinit_internal(struct xpvhv_aux *iter) { 1968 PERL_ARGS_ASSERT_HV_AUXINIT_INTERNAL; 1969 iter->xhv_riter = -1; /* HvRITER(hv) = -1 */ 1970 iter->xhv_eiter = NULL; /* HvEITER(hv) = NULL */ 1971 #ifdef PERL_HASH_RANDOMIZE_KEYS 1972 iter->xhv_last_rand = iter->xhv_rand; 1973 #endif 1974 iter->xhv_fill_lazy = 0; 1975 iter->xhv_name_u.xhvnameu_name = 0; 1976 iter->xhv_name_count = 0; 1977 iter->xhv_backreferences = 0; 1978 iter->xhv_mro_meta = NULL; 1979 iter->xhv_aux_flags = 0; 1980 return iter; 1981 } 1982 1983 1984 static struct xpvhv_aux* 1985 S_hv_auxinit(pTHX_ HV *hv) { 1986 struct xpvhv_aux *iter; 1987 char *array; 1988 1989 PERL_ARGS_ASSERT_HV_AUXINIT; 1990 1991 if (!SvOOK(hv)) { 1992 if (!HvARRAY(hv)) { 1993 Newxz(array, PERL_HV_ARRAY_ALLOC_BYTES(HvMAX(hv) + 1) 1994 + sizeof(struct xpvhv_aux), char); 1995 } else { 1996 array = (char *) HvARRAY(hv); 1997 Renew(array, PERL_HV_ARRAY_ALLOC_BYTES(HvMAX(hv) + 1) 1998 + sizeof(struct xpvhv_aux), char); 1999 } 2000 HvARRAY(hv) = (HE**)array; 2001 SvOOK_on(hv); 2002 iter = HvAUX(hv); 2003 #ifdef PERL_HASH_RANDOMIZE_KEYS 2004 if (PL_HASH_RAND_BITS_ENABLED) { 2005 /* mix in some new state to PL_hash_rand_bits to "randomize" the traversal order*/ 2006 if (PL_HASH_RAND_BITS_ENABLED == 1) 2007 PL_hash_rand_bits += ptr_hash((PTRV)array); 2008 PL_hash_rand_bits = ROTL_UV(PL_hash_rand_bits,1); 2009 } 2010 iter->xhv_rand = (U32)PL_hash_rand_bits; 2011 #endif 2012 } else { 2013 iter = HvAUX(hv); 2014 } 2015 2016 return hv_auxinit_internal(iter); 2017 } 2018 2019 /* 2020 =for apidoc hv_iterinit 2021 2022 Prepares a starting point to traverse a hash table. Returns the number of 2023 keys in the hash (i.e. the same as C<HvUSEDKEYS(hv)>). The return value is 2024 currently only meaningful for hashes without tie magic. 2025 2026 NOTE: Before version 5.004_65, C<hv_iterinit> used to return the number of 2027 hash buckets that happen to be in use. If you still need that esoteric 2028 value, you can get it through the macro C<HvFILL(hv)>. 2029 2030 2031 =cut 2032 */ 2033 2034 I32 2035 Perl_hv_iterinit(pTHX_ HV *hv) 2036 { 2037 PERL_ARGS_ASSERT_HV_ITERINIT; 2038 2039 /* FIXME: Are we not NULL, or do we croak? Place bets now! */ 2040 2041 if (!hv) 2042 Perl_croak(aTHX_ "Bad hash"); 2043 2044 if (SvOOK(hv)) { 2045 struct xpvhv_aux * iter = HvAUX(hv); 2046 HE * const entry = iter->xhv_eiter; /* HvEITER(hv) */ 2047 if (entry && HvLAZYDEL(hv)) { /* was deleted earlier? */ 2048 HvLAZYDEL_off(hv); 2049 hv_free_ent(hv, entry); 2050 } 2051 iter = HvAUX(hv); /* may have been reallocated */ 2052 iter->xhv_riter = -1; /* HvRITER(hv) = -1 */ 2053 iter->xhv_eiter = NULL; /* HvEITER(hv) = NULL */ 2054 #ifdef PERL_HASH_RANDOMIZE_KEYS 2055 iter->xhv_last_rand = iter->xhv_rand; 2056 #endif 2057 } else { 2058 hv_auxinit(hv); 2059 } 2060 2061 /* used to be xhv->xhv_fill before 5.004_65 */ 2062 return HvTOTALKEYS(hv); 2063 } 2064 2065 I32 * 2066 Perl_hv_riter_p(pTHX_ HV *hv) { 2067 struct xpvhv_aux *iter; 2068 2069 PERL_ARGS_ASSERT_HV_RITER_P; 2070 2071 if (!hv) 2072 Perl_croak(aTHX_ "Bad hash"); 2073 2074 iter = SvOOK(hv) ? HvAUX(hv) : hv_auxinit(hv); 2075 return &(iter->xhv_riter); 2076 } 2077 2078 HE ** 2079 Perl_hv_eiter_p(pTHX_ HV *hv) { 2080 struct xpvhv_aux *iter; 2081 2082 PERL_ARGS_ASSERT_HV_EITER_P; 2083 2084 if (!hv) 2085 Perl_croak(aTHX_ "Bad hash"); 2086 2087 iter = SvOOK(hv) ? HvAUX(hv) : hv_auxinit(hv); 2088 return &(iter->xhv_eiter); 2089 } 2090 2091 void 2092 Perl_hv_riter_set(pTHX_ HV *hv, I32 riter) { 2093 struct xpvhv_aux *iter; 2094 2095 PERL_ARGS_ASSERT_HV_RITER_SET; 2096 2097 if (!hv) 2098 Perl_croak(aTHX_ "Bad hash"); 2099 2100 if (SvOOK(hv)) { 2101 iter = HvAUX(hv); 2102 } else { 2103 if (riter == -1) 2104 return; 2105 2106 iter = hv_auxinit(hv); 2107 } 2108 iter->xhv_riter = riter; 2109 } 2110 2111 void 2112 Perl_hv_rand_set(pTHX_ HV *hv, U32 new_xhv_rand) { 2113 struct xpvhv_aux *iter; 2114 2115 PERL_ARGS_ASSERT_HV_RAND_SET; 2116 2117 #ifdef PERL_HASH_RANDOMIZE_KEYS 2118 if (!hv) 2119 Perl_croak(aTHX_ "Bad hash"); 2120 2121 if (SvOOK(hv)) { 2122 iter = HvAUX(hv); 2123 } else { 2124 iter = hv_auxinit(hv); 2125 } 2126 iter->xhv_rand = new_xhv_rand; 2127 #else 2128 Perl_croak(aTHX_ "This Perl has not been built with support for randomized hash key traversal but something called Perl_hv_rand_set()."); 2129 #endif 2130 } 2131 2132 void 2133 Perl_hv_eiter_set(pTHX_ HV *hv, HE *eiter) { 2134 struct xpvhv_aux *iter; 2135 2136 PERL_ARGS_ASSERT_HV_EITER_SET; 2137 2138 if (!hv) 2139 Perl_croak(aTHX_ "Bad hash"); 2140 2141 if (SvOOK(hv)) { 2142 iter = HvAUX(hv); 2143 } else { 2144 /* 0 is the default so don't go malloc()ing a new structure just to 2145 hold 0. */ 2146 if (!eiter) 2147 return; 2148 2149 iter = hv_auxinit(hv); 2150 } 2151 iter->xhv_eiter = eiter; 2152 } 2153 2154 void 2155 Perl_hv_name_set(pTHX_ HV *hv, const char *name, U32 len, U32 flags) 2156 { 2157 dVAR; 2158 struct xpvhv_aux *iter; 2159 U32 hash; 2160 HEK **spot; 2161 2162 PERL_ARGS_ASSERT_HV_NAME_SET; 2163 2164 if (len > I32_MAX) 2165 Perl_croak(aTHX_ "panic: hv name too long (%"UVuf")", (UV) len); 2166 2167 if (SvOOK(hv)) { 2168 iter = HvAUX(hv); 2169 if (iter->xhv_name_u.xhvnameu_name) { 2170 if(iter->xhv_name_count) { 2171 if(flags & HV_NAME_SETALL) { 2172 HEK ** const name = HvAUX(hv)->xhv_name_u.xhvnameu_names; 2173 HEK **hekp = name + ( 2174 iter->xhv_name_count < 0 2175 ? -iter->xhv_name_count 2176 : iter->xhv_name_count 2177 ); 2178 while(hekp-- > name+1) 2179 unshare_hek_or_pvn(*hekp, 0, 0, 0); 2180 /* The first elem may be null. */ 2181 if(*name) unshare_hek_or_pvn(*name, 0, 0, 0); 2182 Safefree(name); 2183 iter = HvAUX(hv); /* may been realloced */ 2184 spot = &iter->xhv_name_u.xhvnameu_name; 2185 iter->xhv_name_count = 0; 2186 } 2187 else { 2188 if(iter->xhv_name_count > 0) { 2189 /* shift some things over */ 2190 Renew( 2191 iter->xhv_name_u.xhvnameu_names, iter->xhv_name_count + 1, HEK * 2192 ); 2193 spot = iter->xhv_name_u.xhvnameu_names; 2194 spot[iter->xhv_name_count] = spot[1]; 2195 spot[1] = spot[0]; 2196 iter->xhv_name_count = -(iter->xhv_name_count + 1); 2197 } 2198 else if(*(spot = iter->xhv_name_u.xhvnameu_names)) { 2199 unshare_hek_or_pvn(*spot, 0, 0, 0); 2200 } 2201 } 2202 } 2203 else if (flags & HV_NAME_SETALL) { 2204 unshare_hek_or_pvn(iter->xhv_name_u.xhvnameu_name, 0, 0, 0); 2205 iter = HvAUX(hv); /* may been realloced */ 2206 spot = &iter->xhv_name_u.xhvnameu_name; 2207 } 2208 else { 2209 HEK * const existing_name = iter->xhv_name_u.xhvnameu_name; 2210 Newx(iter->xhv_name_u.xhvnameu_names, 2, HEK *); 2211 iter->xhv_name_count = -2; 2212 spot = iter->xhv_name_u.xhvnameu_names; 2213 spot[1] = existing_name; 2214 } 2215 } 2216 else { spot = &iter->xhv_name_u.xhvnameu_name; iter->xhv_name_count = 0; } 2217 } else { 2218 if (name == 0) 2219 return; 2220 2221 iter = hv_auxinit(hv); 2222 spot = &iter->xhv_name_u.xhvnameu_name; 2223 } 2224 PERL_HASH(hash, name, len); 2225 *spot = name ? share_hek(name, flags & SVf_UTF8 ? -(I32)len : (I32)len, hash) : NULL; 2226 } 2227 2228 /* 2229 This is basically sv_eq_flags() in sv.c, but we avoid the magic 2230 and bytes checking. 2231 */ 2232 2233 STATIC I32 2234 hek_eq_pvn_flags(pTHX_ const HEK *hek, const char* pv, const I32 pvlen, const U32 flags) { 2235 if ( (HEK_UTF8(hek) ? 1 : 0) != (flags & SVf_UTF8 ? 1 : 0) ) { 2236 if (flags & SVf_UTF8) 2237 return (bytes_cmp_utf8( 2238 (const U8*)HEK_KEY(hek), HEK_LEN(hek), 2239 (const U8*)pv, pvlen) == 0); 2240 else 2241 return (bytes_cmp_utf8( 2242 (const U8*)pv, pvlen, 2243 (const U8*)HEK_KEY(hek), HEK_LEN(hek)) == 0); 2244 } 2245 else 2246 return HEK_LEN(hek) == pvlen && ((HEK_KEY(hek) == pv) 2247 || memEQ(HEK_KEY(hek), pv, pvlen)); 2248 } 2249 2250 /* 2251 =for apidoc hv_ename_add 2252 2253 Adds a name to a stash's internal list of effective names. See 2254 C<hv_ename_delete>. 2255 2256 This is called when a stash is assigned to a new location in the symbol 2257 table. 2258 2259 =cut 2260 */ 2261 2262 void 2263 Perl_hv_ename_add(pTHX_ HV *hv, const char *name, U32 len, U32 flags) 2264 { 2265 dVAR; 2266 struct xpvhv_aux *aux = SvOOK(hv) ? HvAUX(hv) : hv_auxinit(hv); 2267 U32 hash; 2268 2269 PERL_ARGS_ASSERT_HV_ENAME_ADD; 2270 2271 if (len > I32_MAX) 2272 Perl_croak(aTHX_ "panic: hv name too long (%"UVuf")", (UV) len); 2273 2274 PERL_HASH(hash, name, len); 2275 2276 if (aux->xhv_name_count) { 2277 HEK ** const xhv_name = aux->xhv_name_u.xhvnameu_names; 2278 I32 count = aux->xhv_name_count; 2279 HEK **hekp = xhv_name + (count < 0 ? -count : count); 2280 while (hekp-- > xhv_name) 2281 if ( 2282 (HEK_UTF8(*hekp) || (flags & SVf_UTF8)) 2283 ? hek_eq_pvn_flags(aTHX_ *hekp, name, (I32)len, flags) 2284 : (HEK_LEN(*hekp) == (I32)len && memEQ(HEK_KEY(*hekp), name, len)) 2285 ) { 2286 if (hekp == xhv_name && count < 0) 2287 aux->xhv_name_count = -count; 2288 return; 2289 } 2290 if (count < 0) aux->xhv_name_count--, count = -count; 2291 else aux->xhv_name_count++; 2292 Renew(aux->xhv_name_u.xhvnameu_names, count + 1, HEK *); 2293 (aux->xhv_name_u.xhvnameu_names)[count] = share_hek(name, (flags & SVf_UTF8 ? -(I32)len : (I32)len), hash); 2294 } 2295 else { 2296 HEK *existing_name = aux->xhv_name_u.xhvnameu_name; 2297 if ( 2298 existing_name && ( 2299 (HEK_UTF8(existing_name) || (flags & SVf_UTF8)) 2300 ? hek_eq_pvn_flags(aTHX_ existing_name, name, (I32)len, flags) 2301 : (HEK_LEN(existing_name) == (I32)len && memEQ(HEK_KEY(existing_name), name, len)) 2302 ) 2303 ) return; 2304 Newx(aux->xhv_name_u.xhvnameu_names, 2, HEK *); 2305 aux->xhv_name_count = existing_name ? 2 : -2; 2306 *aux->xhv_name_u.xhvnameu_names = existing_name; 2307 (aux->xhv_name_u.xhvnameu_names)[1] = share_hek(name, (flags & SVf_UTF8 ? -(I32)len : (I32)len), hash); 2308 } 2309 } 2310 2311 /* 2312 =for apidoc hv_ename_delete 2313 2314 Removes a name from a stash's internal list of effective names. If this is 2315 the name returned by C<HvENAME>, then another name in the list will take 2316 its place (C<HvENAME> will use it). 2317 2318 This is called when a stash is deleted from the symbol table. 2319 2320 =cut 2321 */ 2322 2323 void 2324 Perl_hv_ename_delete(pTHX_ HV *hv, const char *name, U32 len, U32 flags) 2325 { 2326 dVAR; 2327 struct xpvhv_aux *aux; 2328 2329 PERL_ARGS_ASSERT_HV_ENAME_DELETE; 2330 2331 if (len > I32_MAX) 2332 Perl_croak(aTHX_ "panic: hv name too long (%"UVuf")", (UV) len); 2333 2334 if (!SvOOK(hv)) return; 2335 2336 aux = HvAUX(hv); 2337 if (!aux->xhv_name_u.xhvnameu_name) return; 2338 2339 if (aux->xhv_name_count) { 2340 HEK ** const namep = aux->xhv_name_u.xhvnameu_names; 2341 I32 const count = aux->xhv_name_count; 2342 HEK **victim = namep + (count < 0 ? -count : count); 2343 while (victim-- > namep + 1) 2344 if ( 2345 (HEK_UTF8(*victim) || (flags & SVf_UTF8)) 2346 ? hek_eq_pvn_flags(aTHX_ *victim, name, (I32)len, flags) 2347 : (HEK_LEN(*victim) == (I32)len && memEQ(HEK_KEY(*victim), name, len)) 2348 ) { 2349 unshare_hek_or_pvn(*victim, 0, 0, 0); 2350 aux = HvAUX(hv); /* may been realloced */ 2351 if (count < 0) ++aux->xhv_name_count; 2352 else --aux->xhv_name_count; 2353 if ( 2354 (aux->xhv_name_count == 1 || aux->xhv_name_count == -1) 2355 && !*namep 2356 ) { /* if there are none left */ 2357 Safefree(namep); 2358 aux->xhv_name_u.xhvnameu_names = NULL; 2359 aux->xhv_name_count = 0; 2360 } 2361 else { 2362 /* Move the last one back to fill the empty slot. It 2363 does not matter what order they are in. */ 2364 *victim = *(namep + (count < 0 ? -count : count) - 1); 2365 } 2366 return; 2367 } 2368 if ( 2369 count > 0 && (HEK_UTF8(*namep) || (flags & SVf_UTF8)) 2370 ? hek_eq_pvn_flags(aTHX_ *namep, name, (I32)len, flags) 2371 : (HEK_LEN(*namep) == (I32)len && memEQ(HEK_KEY(*namep), name, len)) 2372 ) { 2373 aux->xhv_name_count = -count; 2374 } 2375 } 2376 else if( 2377 (HEK_UTF8(aux->xhv_name_u.xhvnameu_name) || (flags & SVf_UTF8)) 2378 ? hek_eq_pvn_flags(aTHX_ aux->xhv_name_u.xhvnameu_name, name, (I32)len, flags) 2379 : (HEK_LEN(aux->xhv_name_u.xhvnameu_name) == (I32)len && 2380 memEQ(HEK_KEY(aux->xhv_name_u.xhvnameu_name), name, len)) 2381 ) { 2382 HEK * const namehek = aux->xhv_name_u.xhvnameu_name; 2383 Newx(aux->xhv_name_u.xhvnameu_names, 1, HEK *); 2384 *aux->xhv_name_u.xhvnameu_names = namehek; 2385 aux->xhv_name_count = -1; 2386 } 2387 } 2388 2389 AV ** 2390 Perl_hv_backreferences_p(pTHX_ HV *hv) { 2391 struct xpvhv_aux * const iter = SvOOK(hv) ? HvAUX(hv) : hv_auxinit(hv); 2392 2393 PERL_ARGS_ASSERT_HV_BACKREFERENCES_P; 2394 PERL_UNUSED_CONTEXT; 2395 2396 return &(iter->xhv_backreferences); 2397 } 2398 2399 void 2400 Perl_hv_kill_backrefs(pTHX_ HV *hv) { 2401 AV *av; 2402 2403 PERL_ARGS_ASSERT_HV_KILL_BACKREFS; 2404 2405 if (!SvOOK(hv)) 2406 return; 2407 2408 av = HvAUX(hv)->xhv_backreferences; 2409 2410 if (av) { 2411 HvAUX(hv)->xhv_backreferences = 0; 2412 Perl_sv_kill_backrefs(aTHX_ MUTABLE_SV(hv), av); 2413 if (SvTYPE(av) == SVt_PVAV) 2414 SvREFCNT_dec_NN(av); 2415 } 2416 } 2417 2418 /* 2419 hv_iternext is implemented as a macro in hv.h 2420 2421 =for apidoc hv_iternext 2422 2423 Returns entries from a hash iterator. See C<hv_iterinit>. 2424 2425 You may call C<hv_delete> or C<hv_delete_ent> on the hash entry that the 2426 iterator currently points to, without losing your place or invalidating your 2427 iterator. Note that in this case the current entry is deleted from the hash 2428 with your iterator holding the last reference to it. Your iterator is flagged 2429 to free the entry on the next call to C<hv_iternext>, so you must not discard 2430 your iterator immediately else the entry will leak - call C<hv_iternext> to 2431 trigger the resource deallocation. 2432 2433 =for apidoc hv_iternext_flags 2434 2435 Returns entries from a hash iterator. See C<hv_iterinit> and C<hv_iternext>. 2436 The C<flags> value will normally be zero; if HV_ITERNEXT_WANTPLACEHOLDERS is 2437 set the placeholders keys (for restricted hashes) will be returned in addition 2438 to normal keys. By default placeholders are automatically skipped over. 2439 Currently a placeholder is implemented with a value that is 2440 C<&PL_sv_placeholder>. Note that the implementation of placeholders and 2441 restricted hashes may change, and the implementation currently is 2442 insufficiently abstracted for any change to be tidy. 2443 2444 =cut 2445 */ 2446 2447 HE * 2448 Perl_hv_iternext_flags(pTHX_ HV *hv, I32 flags) 2449 { 2450 dVAR; 2451 XPVHV* xhv; 2452 HE *entry; 2453 HE *oldentry; 2454 MAGIC* mg; 2455 struct xpvhv_aux *iter; 2456 2457 PERL_ARGS_ASSERT_HV_ITERNEXT_FLAGS; 2458 2459 if (!hv) 2460 Perl_croak(aTHX_ "Bad hash"); 2461 2462 xhv = (XPVHV*)SvANY(hv); 2463 2464 if (!SvOOK(hv)) { 2465 /* Too many things (well, pp_each at least) merrily assume that you can 2466 call hv_iternext without calling hv_iterinit, so we'll have to deal 2467 with it. */ 2468 hv_iterinit(hv); 2469 } 2470 iter = HvAUX(hv); 2471 2472 oldentry = entry = iter->xhv_eiter; /* HvEITER(hv) */ 2473 if (SvMAGICAL(hv) && SvRMAGICAL(hv)) { 2474 if ( ( mg = mg_find((const SV *)hv, PERL_MAGIC_tied) ) ) { 2475 SV * const key = sv_newmortal(); 2476 if (entry) { 2477 sv_setsv(key, HeSVKEY_force(entry)); 2478 SvREFCNT_dec(HeSVKEY(entry)); /* get rid of previous key */ 2479 HeSVKEY_set(entry, NULL); 2480 } 2481 else { 2482 char *k; 2483 HEK *hek; 2484 2485 /* one HE per MAGICAL hash */ 2486 iter->xhv_eiter = entry = new_HE(); /* HvEITER(hv) = new_HE() */ 2487 HvLAZYDEL_on(hv); /* make sure entry gets freed */ 2488 Zero(entry, 1, HE); 2489 Newxz(k, HEK_BASESIZE + sizeof(const SV *), char); 2490 hek = (HEK*)k; 2491 HeKEY_hek(entry) = hek; 2492 HeKLEN(entry) = HEf_SVKEY; 2493 } 2494 magic_nextpack(MUTABLE_SV(hv),mg,key); 2495 if (SvOK(key)) { 2496 /* force key to stay around until next time */ 2497 HeSVKEY_set(entry, SvREFCNT_inc_simple_NN(key)); 2498 return entry; /* beware, hent_val is not set */ 2499 } 2500 SvREFCNT_dec(HeVAL(entry)); 2501 Safefree(HeKEY_hek(entry)); 2502 del_HE(entry); 2503 iter = HvAUX(hv); /* may been realloced */ 2504 iter->xhv_eiter = NULL; /* HvEITER(hv) = NULL */ 2505 HvLAZYDEL_off(hv); 2506 return NULL; 2507 } 2508 } 2509 #if defined(DYNAMIC_ENV_FETCH) && !defined(__riscos__) /* set up %ENV for iteration */ 2510 if (!entry && SvRMAGICAL((const SV *)hv) 2511 && mg_find((const SV *)hv, PERL_MAGIC_env)) { 2512 prime_env_iter(); 2513 #ifdef VMS 2514 /* The prime_env_iter() on VMS just loaded up new hash values 2515 * so the iteration count needs to be reset back to the beginning 2516 */ 2517 hv_iterinit(hv); 2518 iter = HvAUX(hv); 2519 oldentry = entry = iter->xhv_eiter; /* HvEITER(hv) */ 2520 #endif 2521 } 2522 #endif 2523 2524 /* hv_iterinit now ensures this. */ 2525 assert (HvARRAY(hv)); 2526 2527 /* At start of hash, entry is NULL. */ 2528 if (entry) 2529 { 2530 entry = HeNEXT(entry); 2531 if (!(flags & HV_ITERNEXT_WANTPLACEHOLDERS)) { 2532 /* 2533 * Skip past any placeholders -- don't want to include them in 2534 * any iteration. 2535 */ 2536 while (entry && HeVAL(entry) == &PL_sv_placeholder) { 2537 entry = HeNEXT(entry); 2538 } 2539 } 2540 } 2541 2542 #ifdef PERL_HASH_RANDOMIZE_KEYS 2543 if (iter->xhv_last_rand != iter->xhv_rand) { 2544 if (iter->xhv_riter != -1) { 2545 Perl_ck_warner_d(aTHX_ packWARN(WARN_INTERNAL), 2546 "Use of each() on hash after insertion without resetting hash iterator results in undefined behavior" 2547 pTHX__FORMAT 2548 pTHX__VALUE); 2549 } 2550 iter = HvAUX(hv); /* may been realloced */ 2551 iter->xhv_last_rand = iter->xhv_rand; 2552 } 2553 #endif 2554 2555 /* Skip the entire loop if the hash is empty. */ 2556 if ((flags & HV_ITERNEXT_WANTPLACEHOLDERS) 2557 ? HvTOTALKEYS(hv) : HvUSEDKEYS(hv)) { 2558 while (!entry) { 2559 /* OK. Come to the end of the current list. Grab the next one. */ 2560 2561 iter->xhv_riter++; /* HvRITER(hv)++ */ 2562 if (iter->xhv_riter > (I32)xhv->xhv_max /* HvRITER(hv) > HvMAX(hv) */) { 2563 /* There is no next one. End of the hash. */ 2564 iter->xhv_riter = -1; /* HvRITER(hv) = -1 */ 2565 #ifdef PERL_HASH_RANDOMIZE_KEYS 2566 iter->xhv_last_rand = iter->xhv_rand; /* reset xhv_last_rand so we can detect inserts during traversal */ 2567 #endif 2568 break; 2569 } 2570 entry = (HvARRAY(hv))[ PERL_HASH_ITER_BUCKET(iter) & xhv->xhv_max ]; 2571 2572 if (!(flags & HV_ITERNEXT_WANTPLACEHOLDERS)) { 2573 /* If we have an entry, but it's a placeholder, don't count it. 2574 Try the next. */ 2575 while (entry && HeVAL(entry) == &PL_sv_placeholder) 2576 entry = HeNEXT(entry); 2577 } 2578 /* Will loop again if this linked list starts NULL 2579 (for HV_ITERNEXT_WANTPLACEHOLDERS) 2580 or if we run through it and find only placeholders. */ 2581 } 2582 } 2583 else { 2584 iter->xhv_riter = -1; 2585 #ifdef PERL_HASH_RANDOMIZE_KEYS 2586 iter->xhv_last_rand = iter->xhv_rand; 2587 #endif 2588 } 2589 2590 if (oldentry && HvLAZYDEL(hv)) { /* was deleted earlier? */ 2591 HvLAZYDEL_off(hv); 2592 hv_free_ent(hv, oldentry); 2593 } 2594 2595 iter = HvAUX(hv); /* may been realloced */ 2596 iter->xhv_eiter = entry; /* HvEITER(hv) = entry */ 2597 return entry; 2598 } 2599 2600 /* 2601 =for apidoc hv_iterkey 2602 2603 Returns the key from the current position of the hash iterator. See 2604 C<hv_iterinit>. 2605 2606 =cut 2607 */ 2608 2609 char * 2610 Perl_hv_iterkey(pTHX_ HE *entry, I32 *retlen) 2611 { 2612 PERL_ARGS_ASSERT_HV_ITERKEY; 2613 2614 if (HeKLEN(entry) == HEf_SVKEY) { 2615 STRLEN len; 2616 char * const p = SvPV(HeKEY_sv(entry), len); 2617 *retlen = len; 2618 return p; 2619 } 2620 else { 2621 *retlen = HeKLEN(entry); 2622 return HeKEY(entry); 2623 } 2624 } 2625 2626 /* unlike hv_iterval(), this always returns a mortal copy of the key */ 2627 /* 2628 =for apidoc hv_iterkeysv 2629 2630 Returns the key as an C<SV*> from the current position of the hash 2631 iterator. The return value will always be a mortal copy of the key. Also 2632 see C<hv_iterinit>. 2633 2634 =cut 2635 */ 2636 2637 SV * 2638 Perl_hv_iterkeysv(pTHX_ HE *entry) 2639 { 2640 PERL_ARGS_ASSERT_HV_ITERKEYSV; 2641 2642 return sv_2mortal(newSVhek(HeKEY_hek(entry))); 2643 } 2644 2645 /* 2646 =for apidoc hv_iterval 2647 2648 Returns the value from the current position of the hash iterator. See 2649 C<hv_iterkey>. 2650 2651 =cut 2652 */ 2653 2654 SV * 2655 Perl_hv_iterval(pTHX_ HV *hv, HE *entry) 2656 { 2657 PERL_ARGS_ASSERT_HV_ITERVAL; 2658 2659 if (SvRMAGICAL(hv)) { 2660 if (mg_find((const SV *)hv, PERL_MAGIC_tied)) { 2661 SV* const sv = sv_newmortal(); 2662 if (HeKLEN(entry) == HEf_SVKEY) 2663 mg_copy(MUTABLE_SV(hv), sv, (char*)HeKEY_sv(entry), HEf_SVKEY); 2664 else 2665 mg_copy(MUTABLE_SV(hv), sv, HeKEY(entry), HeKLEN(entry)); 2666 return sv; 2667 } 2668 } 2669 return HeVAL(entry); 2670 } 2671 2672 /* 2673 =for apidoc hv_iternextsv 2674 2675 Performs an C<hv_iternext>, C<hv_iterkey>, and C<hv_iterval> in one 2676 operation. 2677 2678 =cut 2679 */ 2680 2681 SV * 2682 Perl_hv_iternextsv(pTHX_ HV *hv, char **key, I32 *retlen) 2683 { 2684 HE * const he = hv_iternext_flags(hv, 0); 2685 2686 PERL_ARGS_ASSERT_HV_ITERNEXTSV; 2687 2688 if (!he) 2689 return NULL; 2690 *key = hv_iterkey(he, retlen); 2691 return hv_iterval(hv, he); 2692 } 2693 2694 /* 2695 2696 Now a macro in hv.h 2697 2698 =for apidoc hv_magic 2699 2700 Adds magic to a hash. See C<sv_magic>. 2701 2702 =cut 2703 */ 2704 2705 /* possibly free a shared string if no one has access to it 2706 * len and hash must both be valid for str. 2707 */ 2708 void 2709 Perl_unsharepvn(pTHX_ const char *str, I32 len, U32 hash) 2710 { 2711 unshare_hek_or_pvn (NULL, str, len, hash); 2712 } 2713 2714 2715 void 2716 Perl_unshare_hek(pTHX_ HEK *hek) 2717 { 2718 assert(hek); 2719 unshare_hek_or_pvn(hek, NULL, 0, 0); 2720 } 2721 2722 /* possibly free a shared string if no one has access to it 2723 hek if non-NULL takes priority over the other 3, else str, len and hash 2724 are used. If so, len and hash must both be valid for str. 2725 */ 2726 STATIC void 2727 S_unshare_hek_or_pvn(pTHX_ const HEK *hek, const char *str, I32 len, U32 hash) 2728 { 2729 dVAR; 2730 XPVHV* xhv; 2731 HE *entry; 2732 HE **oentry; 2733 bool is_utf8 = FALSE; 2734 int k_flags = 0; 2735 const char * const save = str; 2736 struct shared_he *he = NULL; 2737 2738 if (hek) { 2739 /* Find the shared he which is just before us in memory. */ 2740 he = (struct shared_he *)(((char *)hek) 2741 - STRUCT_OFFSET(struct shared_he, 2742 shared_he_hek)); 2743 2744 /* Assert that the caller passed us a genuine (or at least consistent) 2745 shared hek */ 2746 assert (he->shared_he_he.hent_hek == hek); 2747 2748 if (he->shared_he_he.he_valu.hent_refcount - 1) { 2749 --he->shared_he_he.he_valu.hent_refcount; 2750 return; 2751 } 2752 2753 hash = HEK_HASH(hek); 2754 } else if (len < 0) { 2755 STRLEN tmplen = -len; 2756 is_utf8 = TRUE; 2757 /* See the note in hv_fetch(). --jhi */ 2758 str = (char*)bytes_from_utf8((U8*)str, &tmplen, &is_utf8); 2759 len = tmplen; 2760 if (is_utf8) 2761 k_flags = HVhek_UTF8; 2762 if (str != save) 2763 k_flags |= HVhek_WASUTF8 | HVhek_FREEKEY; 2764 } 2765 2766 /* what follows was the moral equivalent of: 2767 if ((Svp = hv_fetch(PL_strtab, tmpsv, FALSE, hash))) { 2768 if (--*Svp == NULL) 2769 hv_delete(PL_strtab, str, len, G_DISCARD, hash); 2770 } */ 2771 xhv = (XPVHV*)SvANY(PL_strtab); 2772 /* assert(xhv_array != 0) */ 2773 oentry = &(HvARRAY(PL_strtab))[hash & (I32) HvMAX(PL_strtab)]; 2774 if (he) { 2775 const HE *const he_he = &(he->shared_he_he); 2776 for (entry = *oentry; entry; oentry = &HeNEXT(entry), entry = *oentry) { 2777 if (entry == he_he) 2778 break; 2779 } 2780 } else { 2781 const int flags_masked = k_flags & HVhek_MASK; 2782 for (entry = *oentry; entry; oentry = &HeNEXT(entry), entry = *oentry) { 2783 if (HeHASH(entry) != hash) /* strings can't be equal */ 2784 continue; 2785 if (HeKLEN(entry) != len) 2786 continue; 2787 if (HeKEY(entry) != str && memNE(HeKEY(entry),str,len)) /* is this it? */ 2788 continue; 2789 if (HeKFLAGS(entry) != flags_masked) 2790 continue; 2791 break; 2792 } 2793 } 2794 2795 if (entry) { 2796 if (--entry->he_valu.hent_refcount == 0) { 2797 *oentry = HeNEXT(entry); 2798 Safefree(entry); 2799 xhv->xhv_keys--; /* HvTOTALKEYS(hv)-- */ 2800 } 2801 } 2802 2803 if (!entry) 2804 Perl_ck_warner_d(aTHX_ packWARN(WARN_INTERNAL), 2805 "Attempt to free nonexistent shared string '%s'%s" 2806 pTHX__FORMAT, 2807 hek ? HEK_KEY(hek) : str, 2808 ((k_flags & HVhek_UTF8) ? " (utf8)" : "") pTHX__VALUE); 2809 if (k_flags & HVhek_FREEKEY) 2810 Safefree(str); 2811 } 2812 2813 /* get a (constant) string ptr from the global string table 2814 * string will get added if it is not already there. 2815 * len and hash must both be valid for str. 2816 */ 2817 HEK * 2818 Perl_share_hek(pTHX_ const char *str, I32 len, U32 hash) 2819 { 2820 bool is_utf8 = FALSE; 2821 int flags = 0; 2822 const char * const save = str; 2823 2824 PERL_ARGS_ASSERT_SHARE_HEK; 2825 2826 if (len < 0) { 2827 STRLEN tmplen = -len; 2828 is_utf8 = TRUE; 2829 /* See the note in hv_fetch(). --jhi */ 2830 str = (char*)bytes_from_utf8((U8*)str, &tmplen, &is_utf8); 2831 len = tmplen; 2832 /* If we were able to downgrade here, then than means that we were passed 2833 in a key which only had chars 0-255, but was utf8 encoded. */ 2834 if (is_utf8) 2835 flags = HVhek_UTF8; 2836 /* If we found we were able to downgrade the string to bytes, then 2837 we should flag that it needs upgrading on keys or each. Also flag 2838 that we need share_hek_flags to free the string. */ 2839 if (str != save) { 2840 dVAR; 2841 PERL_HASH(hash, str, len); 2842 flags |= HVhek_WASUTF8 | HVhek_FREEKEY; 2843 } 2844 } 2845 2846 return share_hek_flags (str, len, hash, flags); 2847 } 2848 2849 STATIC HEK * 2850 S_share_hek_flags(pTHX_ const char *str, I32 len, U32 hash, int flags) 2851 { 2852 dVAR; 2853 HE *entry; 2854 const int flags_masked = flags & HVhek_MASK; 2855 const U32 hindex = hash & (I32) HvMAX(PL_strtab); 2856 XPVHV * const xhv = (XPVHV*)SvANY(PL_strtab); 2857 2858 PERL_ARGS_ASSERT_SHARE_HEK_FLAGS; 2859 2860 /* what follows is the moral equivalent of: 2861 2862 if (!(Svp = hv_fetch(PL_strtab, str, len, FALSE))) 2863 hv_store(PL_strtab, str, len, NULL, hash); 2864 2865 Can't rehash the shared string table, so not sure if it's worth 2866 counting the number of entries in the linked list 2867 */ 2868 2869 /* assert(xhv_array != 0) */ 2870 entry = (HvARRAY(PL_strtab))[hindex]; 2871 for (;entry; entry = HeNEXT(entry)) { 2872 if (HeHASH(entry) != hash) /* strings can't be equal */ 2873 continue; 2874 if (HeKLEN(entry) != len) 2875 continue; 2876 if (HeKEY(entry) != str && memNE(HeKEY(entry),str,len)) /* is this it? */ 2877 continue; 2878 if (HeKFLAGS(entry) != flags_masked) 2879 continue; 2880 break; 2881 } 2882 2883 if (!entry) { 2884 /* What used to be head of the list. 2885 If this is NULL, then we're the first entry for this slot, which 2886 means we need to increate fill. */ 2887 struct shared_he *new_entry; 2888 HEK *hek; 2889 char *k; 2890 HE **const head = &HvARRAY(PL_strtab)[hindex]; 2891 HE *const next = *head; 2892 2893 /* We don't actually store a HE from the arena and a regular HEK. 2894 Instead we allocate one chunk of memory big enough for both, 2895 and put the HEK straight after the HE. This way we can find the 2896 HE directly from the HEK. 2897 */ 2898 2899 Newx(k, STRUCT_OFFSET(struct shared_he, 2900 shared_he_hek.hek_key[0]) + len + 2, char); 2901 new_entry = (struct shared_he *)k; 2902 entry = &(new_entry->shared_he_he); 2903 hek = &(new_entry->shared_he_hek); 2904 2905 Copy(str, HEK_KEY(hek), len, char); 2906 HEK_KEY(hek)[len] = 0; 2907 HEK_LEN(hek) = len; 2908 HEK_HASH(hek) = hash; 2909 HEK_FLAGS(hek) = (unsigned char)flags_masked; 2910 2911 /* Still "point" to the HEK, so that other code need not know what 2912 we're up to. */ 2913 HeKEY_hek(entry) = hek; 2914 entry->he_valu.hent_refcount = 0; 2915 HeNEXT(entry) = next; 2916 *head = entry; 2917 2918 xhv->xhv_keys++; /* HvTOTALKEYS(hv)++ */ 2919 if (!next) { /* initial entry? */ 2920 } else if ( DO_HSPLIT(xhv) ) { 2921 const STRLEN oldsize = xhv->xhv_max + 1; 2922 hsplit(PL_strtab, oldsize, oldsize * 2); 2923 } 2924 } 2925 2926 ++entry->he_valu.hent_refcount; 2927 2928 if (flags & HVhek_FREEKEY) 2929 Safefree(str); 2930 2931 return HeKEY_hek(entry); 2932 } 2933 2934 SSize_t * 2935 Perl_hv_placeholders_p(pTHX_ HV *hv) 2936 { 2937 dVAR; 2938 MAGIC *mg = mg_find((const SV *)hv, PERL_MAGIC_rhash); 2939 2940 PERL_ARGS_ASSERT_HV_PLACEHOLDERS_P; 2941 2942 if (!mg) { 2943 mg = sv_magicext(MUTABLE_SV(hv), 0, PERL_MAGIC_rhash, 0, 0, 0); 2944 2945 if (!mg) { 2946 Perl_die(aTHX_ "panic: hv_placeholders_p"); 2947 } 2948 } 2949 return &(mg->mg_len); 2950 } 2951 2952 2953 I32 2954 Perl_hv_placeholders_get(pTHX_ const HV *hv) 2955 { 2956 dVAR; 2957 MAGIC * const mg = mg_find((const SV *)hv, PERL_MAGIC_rhash); 2958 2959 PERL_ARGS_ASSERT_HV_PLACEHOLDERS_GET; 2960 2961 return mg ? mg->mg_len : 0; 2962 } 2963 2964 void 2965 Perl_hv_placeholders_set(pTHX_ HV *hv, I32 ph) 2966 { 2967 dVAR; 2968 MAGIC * const mg = mg_find((const SV *)hv, PERL_MAGIC_rhash); 2969 2970 PERL_ARGS_ASSERT_HV_PLACEHOLDERS_SET; 2971 2972 if (mg) { 2973 mg->mg_len = ph; 2974 } else if (ph) { 2975 if (!sv_magicext(MUTABLE_SV(hv), 0, PERL_MAGIC_rhash, 0, 0, ph)) 2976 Perl_die(aTHX_ "panic: hv_placeholders_set"); 2977 } 2978 /* else we don't need to add magic to record 0 placeholders. */ 2979 } 2980 2981 STATIC SV * 2982 S_refcounted_he_value(pTHX_ const struct refcounted_he *he) 2983 { 2984 dVAR; 2985 SV *value; 2986 2987 PERL_ARGS_ASSERT_REFCOUNTED_HE_VALUE; 2988 2989 switch(he->refcounted_he_data[0] & HVrhek_typemask) { 2990 case HVrhek_undef: 2991 value = newSV(0); 2992 break; 2993 case HVrhek_delete: 2994 value = &PL_sv_placeholder; 2995 break; 2996 case HVrhek_IV: 2997 value = newSViv(he->refcounted_he_val.refcounted_he_u_iv); 2998 break; 2999 case HVrhek_UV: 3000 value = newSVuv(he->refcounted_he_val.refcounted_he_u_uv); 3001 break; 3002 case HVrhek_PV: 3003 case HVrhek_PV_UTF8: 3004 /* Create a string SV that directly points to the bytes in our 3005 structure. */ 3006 value = newSV_type(SVt_PV); 3007 SvPV_set(value, (char *) he->refcounted_he_data + 1); 3008 SvCUR_set(value, he->refcounted_he_val.refcounted_he_u_len); 3009 /* This stops anything trying to free it */ 3010 SvLEN_set(value, 0); 3011 SvPOK_on(value); 3012 SvREADONLY_on(value); 3013 if ((he->refcounted_he_data[0] & HVrhek_typemask) == HVrhek_PV_UTF8) 3014 SvUTF8_on(value); 3015 break; 3016 default: 3017 Perl_croak(aTHX_ "panic: refcounted_he_value bad flags %"UVxf, 3018 (UV)he->refcounted_he_data[0]); 3019 } 3020 return value; 3021 } 3022 3023 /* 3024 =for apidoc m|HV *|refcounted_he_chain_2hv|const struct refcounted_he *c|U32 flags 3025 3026 Generates and returns a C<HV *> representing the content of a 3027 C<refcounted_he> chain. 3028 I<flags> is currently unused and must be zero. 3029 3030 =cut 3031 */ 3032 HV * 3033 Perl_refcounted_he_chain_2hv(pTHX_ const struct refcounted_he *chain, U32 flags) 3034 { 3035 dVAR; 3036 HV *hv; 3037 U32 placeholders, max; 3038 3039 if (flags) 3040 Perl_croak(aTHX_ "panic: refcounted_he_chain_2hv bad flags %"UVxf, 3041 (UV)flags); 3042 3043 /* We could chase the chain once to get an idea of the number of keys, 3044 and call ksplit. But for now we'll make a potentially inefficient 3045 hash with only 8 entries in its array. */ 3046 hv = newHV(); 3047 max = HvMAX(hv); 3048 if (!HvARRAY(hv)) { 3049 char *array; 3050 Newxz(array, PERL_HV_ARRAY_ALLOC_BYTES(max + 1), char); 3051 HvARRAY(hv) = (HE**)array; 3052 } 3053 3054 placeholders = 0; 3055 while (chain) { 3056 #ifdef USE_ITHREADS 3057 U32 hash = chain->refcounted_he_hash; 3058 #else 3059 U32 hash = HEK_HASH(chain->refcounted_he_hek); 3060 #endif 3061 HE **oentry = &((HvARRAY(hv))[hash & max]); 3062 HE *entry = *oentry; 3063 SV *value; 3064 3065 for (; entry; entry = HeNEXT(entry)) { 3066 if (HeHASH(entry) == hash) { 3067 /* We might have a duplicate key here. If so, entry is older 3068 than the key we've already put in the hash, so if they are 3069 the same, skip adding entry. */ 3070 #ifdef USE_ITHREADS 3071 const STRLEN klen = HeKLEN(entry); 3072 const char *const key = HeKEY(entry); 3073 if (klen == chain->refcounted_he_keylen 3074 && (!!HeKUTF8(entry) 3075 == !!(chain->refcounted_he_data[0] & HVhek_UTF8)) 3076 && memEQ(key, REF_HE_KEY(chain), klen)) 3077 goto next_please; 3078 #else 3079 if (HeKEY_hek(entry) == chain->refcounted_he_hek) 3080 goto next_please; 3081 if (HeKLEN(entry) == HEK_LEN(chain->refcounted_he_hek) 3082 && HeKUTF8(entry) == HEK_UTF8(chain->refcounted_he_hek) 3083 && memEQ(HeKEY(entry), HEK_KEY(chain->refcounted_he_hek), 3084 HeKLEN(entry))) 3085 goto next_please; 3086 #endif 3087 } 3088 } 3089 assert (!entry); 3090 entry = new_HE(); 3091 3092 #ifdef USE_ITHREADS 3093 HeKEY_hek(entry) 3094 = share_hek_flags(REF_HE_KEY(chain), 3095 chain->refcounted_he_keylen, 3096 chain->refcounted_he_hash, 3097 (chain->refcounted_he_data[0] 3098 & (HVhek_UTF8|HVhek_WASUTF8))); 3099 #else 3100 HeKEY_hek(entry) = share_hek_hek(chain->refcounted_he_hek); 3101 #endif 3102 value = refcounted_he_value(chain); 3103 if (value == &PL_sv_placeholder) 3104 placeholders++; 3105 HeVAL(entry) = value; 3106 3107 /* Link it into the chain. */ 3108 HeNEXT(entry) = *oentry; 3109 *oentry = entry; 3110 3111 HvTOTALKEYS(hv)++; 3112 3113 next_please: 3114 chain = chain->refcounted_he_next; 3115 } 3116 3117 if (placeholders) { 3118 clear_placeholders(hv, placeholders); 3119 HvTOTALKEYS(hv) -= placeholders; 3120 } 3121 3122 /* We could check in the loop to see if we encounter any keys with key 3123 flags, but it's probably not worth it, as this per-hash flag is only 3124 really meant as an optimisation for things like Storable. */ 3125 HvHASKFLAGS_on(hv); 3126 DEBUG_A(Perl_hv_assert(aTHX_ hv)); 3127 3128 return hv; 3129 } 3130 3131 /* 3132 =for apidoc m|SV *|refcounted_he_fetch_pvn|const struct refcounted_he *chain|const char *keypv|STRLEN keylen|U32 hash|U32 flags 3133 3134 Search along a C<refcounted_he> chain for an entry with the key specified 3135 by I<keypv> and I<keylen>. If I<flags> has the C<REFCOUNTED_HE_KEY_UTF8> 3136 bit set, the key octets are interpreted as UTF-8, otherwise they 3137 are interpreted as Latin-1. I<hash> is a precomputed hash of the key 3138 string, or zero if it has not been precomputed. Returns a mortal scalar 3139 representing the value associated with the key, or C<&PL_sv_placeholder> 3140 if there is no value associated with the key. 3141 3142 =cut 3143 */ 3144 3145 SV * 3146 Perl_refcounted_he_fetch_pvn(pTHX_ const struct refcounted_he *chain, 3147 const char *keypv, STRLEN keylen, U32 hash, U32 flags) 3148 { 3149 dVAR; 3150 U8 utf8_flag; 3151 PERL_ARGS_ASSERT_REFCOUNTED_HE_FETCH_PVN; 3152 3153 if (flags & ~(REFCOUNTED_HE_KEY_UTF8|REFCOUNTED_HE_EXISTS)) 3154 Perl_croak(aTHX_ "panic: refcounted_he_fetch_pvn bad flags %"UVxf, 3155 (UV)flags); 3156 if (!chain) 3157 goto ret; 3158 if (flags & REFCOUNTED_HE_KEY_UTF8) { 3159 /* For searching purposes, canonicalise to Latin-1 where possible. */ 3160 const char *keyend = keypv + keylen, *p; 3161 STRLEN nonascii_count = 0; 3162 for (p = keypv; p != keyend; p++) { 3163 if (! UTF8_IS_INVARIANT(*p)) { 3164 if (! UTF8_IS_NEXT_CHAR_DOWNGRADEABLE(p, keyend)) { 3165 goto canonicalised_key; 3166 } 3167 nonascii_count++; 3168 p++; 3169 } 3170 } 3171 if (nonascii_count) { 3172 char *q; 3173 const char *p = keypv, *keyend = keypv + keylen; 3174 keylen -= nonascii_count; 3175 Newx(q, keylen, char); 3176 SAVEFREEPV(q); 3177 keypv = q; 3178 for (; p != keyend; p++, q++) { 3179 U8 c = (U8)*p; 3180 if (UTF8_IS_INVARIANT(c)) { 3181 *q = (char) c; 3182 } 3183 else { 3184 p++; 3185 *q = (char) TWO_BYTE_UTF8_TO_NATIVE(c, *p); 3186 } 3187 } 3188 } 3189 flags &= ~REFCOUNTED_HE_KEY_UTF8; 3190 canonicalised_key: ; 3191 } 3192 utf8_flag = (flags & REFCOUNTED_HE_KEY_UTF8) ? HVhek_UTF8 : 0; 3193 if (!hash) 3194 PERL_HASH(hash, keypv, keylen); 3195 3196 for (; chain; chain = chain->refcounted_he_next) { 3197 if ( 3198 #ifdef USE_ITHREADS 3199 hash == chain->refcounted_he_hash && 3200 keylen == chain->refcounted_he_keylen && 3201 memEQ(REF_HE_KEY(chain), keypv, keylen) && 3202 utf8_flag == (chain->refcounted_he_data[0] & HVhek_UTF8) 3203 #else 3204 hash == HEK_HASH(chain->refcounted_he_hek) && 3205 keylen == (STRLEN)HEK_LEN(chain->refcounted_he_hek) && 3206 memEQ(HEK_KEY(chain->refcounted_he_hek), keypv, keylen) && 3207 utf8_flag == (HEK_FLAGS(chain->refcounted_he_hek) & HVhek_UTF8) 3208 #endif 3209 ) { 3210 if (flags & REFCOUNTED_HE_EXISTS) 3211 return (chain->refcounted_he_data[0] & HVrhek_typemask) 3212 == HVrhek_delete 3213 ? NULL : &PL_sv_yes; 3214 return sv_2mortal(refcounted_he_value(chain)); 3215 } 3216 } 3217 ret: 3218 return flags & REFCOUNTED_HE_EXISTS ? NULL : &PL_sv_placeholder; 3219 } 3220 3221 /* 3222 =for apidoc m|SV *|refcounted_he_fetch_pv|const struct refcounted_he *chain|const char *key|U32 hash|U32 flags 3223 3224 Like L</refcounted_he_fetch_pvn>, but takes a nul-terminated string 3225 instead of a string/length pair. 3226 3227 =cut 3228 */ 3229 3230 SV * 3231 Perl_refcounted_he_fetch_pv(pTHX_ const struct refcounted_he *chain, 3232 const char *key, U32 hash, U32 flags) 3233 { 3234 PERL_ARGS_ASSERT_REFCOUNTED_HE_FETCH_PV; 3235 return refcounted_he_fetch_pvn(chain, key, strlen(key), hash, flags); 3236 } 3237 3238 /* 3239 =for apidoc m|SV *|refcounted_he_fetch_sv|const struct refcounted_he *chain|SV *key|U32 hash|U32 flags 3240 3241 Like L</refcounted_he_fetch_pvn>, but takes a Perl scalar instead of a 3242 string/length pair. 3243 3244 =cut 3245 */ 3246 3247 SV * 3248 Perl_refcounted_he_fetch_sv(pTHX_ const struct refcounted_he *chain, 3249 SV *key, U32 hash, U32 flags) 3250 { 3251 const char *keypv; 3252 STRLEN keylen; 3253 PERL_ARGS_ASSERT_REFCOUNTED_HE_FETCH_SV; 3254 if (flags & REFCOUNTED_HE_KEY_UTF8) 3255 Perl_croak(aTHX_ "panic: refcounted_he_fetch_sv bad flags %"UVxf, 3256 (UV)flags); 3257 keypv = SvPV_const(key, keylen); 3258 if (SvUTF8(key)) 3259 flags |= REFCOUNTED_HE_KEY_UTF8; 3260 if (!hash && SvIsCOW_shared_hash(key)) 3261 hash = SvSHARED_HASH(key); 3262 return refcounted_he_fetch_pvn(chain, keypv, keylen, hash, flags); 3263 } 3264 3265 /* 3266 =for apidoc m|struct refcounted_he *|refcounted_he_new_pvn|struct refcounted_he *parent|const char *keypv|STRLEN keylen|U32 hash|SV *value|U32 flags 3267 3268 Creates a new C<refcounted_he>. This consists of a single key/value 3269 pair and a reference to an existing C<refcounted_he> chain (which may 3270 be empty), and thus forms a longer chain. When using the longer chain, 3271 the new key/value pair takes precedence over any entry for the same key 3272 further along the chain. 3273 3274 The new key is specified by I<keypv> and I<keylen>. If I<flags> has 3275 the C<REFCOUNTED_HE_KEY_UTF8> bit set, the key octets are interpreted 3276 as UTF-8, otherwise they are interpreted as Latin-1. I<hash> is 3277 a precomputed hash of the key string, or zero if it has not been 3278 precomputed. 3279 3280 I<value> is the scalar value to store for this key. I<value> is copied 3281 by this function, which thus does not take ownership of any reference 3282 to it, and later changes to the scalar will not be reflected in the 3283 value visible in the C<refcounted_he>. Complex types of scalar will not 3284 be stored with referential integrity, but will be coerced to strings. 3285 I<value> may be either null or C<&PL_sv_placeholder> to indicate that no 3286 value is to be associated with the key; this, as with any non-null value, 3287 takes precedence over the existence of a value for the key further along 3288 the chain. 3289 3290 I<parent> points to the rest of the C<refcounted_he> chain to be 3291 attached to the new C<refcounted_he>. This function takes ownership 3292 of one reference to I<parent>, and returns one reference to the new 3293 C<refcounted_he>. 3294 3295 =cut 3296 */ 3297 3298 struct refcounted_he * 3299 Perl_refcounted_he_new_pvn(pTHX_ struct refcounted_he *parent, 3300 const char *keypv, STRLEN keylen, U32 hash, SV *value, U32 flags) 3301 { 3302 dVAR; 3303 STRLEN value_len = 0; 3304 const char *value_p = NULL; 3305 bool is_pv; 3306 char value_type; 3307 char hekflags; 3308 STRLEN key_offset = 1; 3309 struct refcounted_he *he; 3310 PERL_ARGS_ASSERT_REFCOUNTED_HE_NEW_PVN; 3311 3312 if (!value || value == &PL_sv_placeholder) { 3313 value_type = HVrhek_delete; 3314 } else if (SvPOK(value)) { 3315 value_type = HVrhek_PV; 3316 } else if (SvIOK(value)) { 3317 value_type = SvUOK((const SV *)value) ? HVrhek_UV : HVrhek_IV; 3318 } else if (!SvOK(value)) { 3319 value_type = HVrhek_undef; 3320 } else { 3321 value_type = HVrhek_PV; 3322 } 3323 is_pv = value_type == HVrhek_PV; 3324 if (is_pv) { 3325 /* Do it this way so that the SvUTF8() test is after the SvPV, in case 3326 the value is overloaded, and doesn't yet have the UTF-8flag set. */ 3327 value_p = SvPV_const(value, value_len); 3328 if (SvUTF8(value)) 3329 value_type = HVrhek_PV_UTF8; 3330 key_offset = value_len + 2; 3331 } 3332 hekflags = value_type; 3333 3334 if (flags & REFCOUNTED_HE_KEY_UTF8) { 3335 /* Canonicalise to Latin-1 where possible. */ 3336 const char *keyend = keypv + keylen, *p; 3337 STRLEN nonascii_count = 0; 3338 for (p = keypv; p != keyend; p++) { 3339 if (! UTF8_IS_INVARIANT(*p)) { 3340 if (! UTF8_IS_NEXT_CHAR_DOWNGRADEABLE(p, keyend)) { 3341 goto canonicalised_key; 3342 } 3343 nonascii_count++; 3344 p++; 3345 } 3346 } 3347 if (nonascii_count) { 3348 char *q; 3349 const char *p = keypv, *keyend = keypv + keylen; 3350 keylen -= nonascii_count; 3351 Newx(q, keylen, char); 3352 SAVEFREEPV(q); 3353 keypv = q; 3354 for (; p != keyend; p++, q++) { 3355 U8 c = (U8)*p; 3356 if (UTF8_IS_INVARIANT(c)) { 3357 *q = (char) c; 3358 } 3359 else { 3360 p++; 3361 *q = (char) TWO_BYTE_UTF8_TO_NATIVE(c, *p); 3362 } 3363 } 3364 } 3365 flags &= ~REFCOUNTED_HE_KEY_UTF8; 3366 canonicalised_key: ; 3367 } 3368 if (flags & REFCOUNTED_HE_KEY_UTF8) 3369 hekflags |= HVhek_UTF8; 3370 if (!hash) 3371 PERL_HASH(hash, keypv, keylen); 3372 3373 #ifdef USE_ITHREADS 3374 he = (struct refcounted_he*) 3375 PerlMemShared_malloc(sizeof(struct refcounted_he) - 1 3376 + keylen 3377 + key_offset); 3378 #else 3379 he = (struct refcounted_he*) 3380 PerlMemShared_malloc(sizeof(struct refcounted_he) - 1 3381 + key_offset); 3382 #endif 3383 3384 he->refcounted_he_next = parent; 3385 3386 if (is_pv) { 3387 Copy(value_p, he->refcounted_he_data + 1, value_len + 1, char); 3388 he->refcounted_he_val.refcounted_he_u_len = value_len; 3389 } else if (value_type == HVrhek_IV) { 3390 he->refcounted_he_val.refcounted_he_u_iv = SvIVX(value); 3391 } else if (value_type == HVrhek_UV) { 3392 he->refcounted_he_val.refcounted_he_u_uv = SvUVX(value); 3393 } 3394 3395 #ifdef USE_ITHREADS 3396 he->refcounted_he_hash = hash; 3397 he->refcounted_he_keylen = keylen; 3398 Copy(keypv, he->refcounted_he_data + key_offset, keylen, char); 3399 #else 3400 he->refcounted_he_hek = share_hek_flags(keypv, keylen, hash, hekflags); 3401 #endif 3402 3403 he->refcounted_he_data[0] = hekflags; 3404 he->refcounted_he_refcnt = 1; 3405 3406 return he; 3407 } 3408 3409 /* 3410 =for apidoc m|struct refcounted_he *|refcounted_he_new_pv|struct refcounted_he *parent|const char *key|U32 hash|SV *value|U32 flags 3411 3412 Like L</refcounted_he_new_pvn>, but takes a nul-terminated string instead 3413 of a string/length pair. 3414 3415 =cut 3416 */ 3417 3418 struct refcounted_he * 3419 Perl_refcounted_he_new_pv(pTHX_ struct refcounted_he *parent, 3420 const char *key, U32 hash, SV *value, U32 flags) 3421 { 3422 PERL_ARGS_ASSERT_REFCOUNTED_HE_NEW_PV; 3423 return refcounted_he_new_pvn(parent, key, strlen(key), hash, value, flags); 3424 } 3425 3426 /* 3427 =for apidoc m|struct refcounted_he *|refcounted_he_new_sv|struct refcounted_he *parent|SV *key|U32 hash|SV *value|U32 flags 3428 3429 Like L</refcounted_he_new_pvn>, but takes a Perl scalar instead of a 3430 string/length pair. 3431 3432 =cut 3433 */ 3434 3435 struct refcounted_he * 3436 Perl_refcounted_he_new_sv(pTHX_ struct refcounted_he *parent, 3437 SV *key, U32 hash, SV *value, U32 flags) 3438 { 3439 const char *keypv; 3440 STRLEN keylen; 3441 PERL_ARGS_ASSERT_REFCOUNTED_HE_NEW_SV; 3442 if (flags & REFCOUNTED_HE_KEY_UTF8) 3443 Perl_croak(aTHX_ "panic: refcounted_he_new_sv bad flags %"UVxf, 3444 (UV)flags); 3445 keypv = SvPV_const(key, keylen); 3446 if (SvUTF8(key)) 3447 flags |= REFCOUNTED_HE_KEY_UTF8; 3448 if (!hash && SvIsCOW_shared_hash(key)) 3449 hash = SvSHARED_HASH(key); 3450 return refcounted_he_new_pvn(parent, keypv, keylen, hash, value, flags); 3451 } 3452 3453 /* 3454 =for apidoc m|void|refcounted_he_free|struct refcounted_he *he 3455 3456 Decrements the reference count of a C<refcounted_he> by one. If the 3457 reference count reaches zero the structure's memory is freed, which 3458 (recursively) causes a reduction of its parent C<refcounted_he>'s 3459 reference count. It is safe to pass a null pointer to this function: 3460 no action occurs in this case. 3461 3462 =cut 3463 */ 3464 3465 void 3466 Perl_refcounted_he_free(pTHX_ struct refcounted_he *he) { 3467 dVAR; 3468 PERL_UNUSED_CONTEXT; 3469 3470 while (he) { 3471 struct refcounted_he *copy; 3472 U32 new_count; 3473 3474 HINTS_REFCNT_LOCK; 3475 new_count = --he->refcounted_he_refcnt; 3476 HINTS_REFCNT_UNLOCK; 3477 3478 if (new_count) { 3479 return; 3480 } 3481 3482 #ifndef USE_ITHREADS 3483 unshare_hek_or_pvn (he->refcounted_he_hek, 0, 0, 0); 3484 #endif 3485 copy = he; 3486 he = he->refcounted_he_next; 3487 PerlMemShared_free(copy); 3488 } 3489 } 3490 3491 /* 3492 =for apidoc m|struct refcounted_he *|refcounted_he_inc|struct refcounted_he *he 3493 3494 Increment the reference count of a C<refcounted_he>. The pointer to the 3495 C<refcounted_he> is also returned. It is safe to pass a null pointer 3496 to this function: no action occurs and a null pointer is returned. 3497 3498 =cut 3499 */ 3500 3501 struct refcounted_he * 3502 Perl_refcounted_he_inc(pTHX_ struct refcounted_he *he) 3503 { 3504 dVAR; 3505 if (he) { 3506 HINTS_REFCNT_LOCK; 3507 he->refcounted_he_refcnt++; 3508 HINTS_REFCNT_UNLOCK; 3509 } 3510 return he; 3511 } 3512 3513 /* 3514 =for apidoc cop_fetch_label 3515 3516 Returns the label attached to a cop. 3517 The flags pointer may be set to C<SVf_UTF8> or 0. 3518 3519 =cut 3520 */ 3521 3522 /* pp_entereval is aware that labels are stored with a key ':' at the top of 3523 the linked list. */ 3524 const char * 3525 Perl_cop_fetch_label(pTHX_ COP *const cop, STRLEN *len, U32 *flags) { 3526 struct refcounted_he *const chain = cop->cop_hints_hash; 3527 3528 PERL_ARGS_ASSERT_COP_FETCH_LABEL; 3529 3530 if (!chain) 3531 return NULL; 3532 #ifdef USE_ITHREADS 3533 if (chain->refcounted_he_keylen != 1) 3534 return NULL; 3535 if (*REF_HE_KEY(chain) != ':') 3536 return NULL; 3537 #else 3538 if ((STRLEN)HEK_LEN(chain->refcounted_he_hek) != 1) 3539 return NULL; 3540 if (*HEK_KEY(chain->refcounted_he_hek) != ':') 3541 return NULL; 3542 #endif 3543 /* Stop anyone trying to really mess us up by adding their own value for 3544 ':' into %^H */ 3545 if ((chain->refcounted_he_data[0] & HVrhek_typemask) != HVrhek_PV 3546 && (chain->refcounted_he_data[0] & HVrhek_typemask) != HVrhek_PV_UTF8) 3547 return NULL; 3548 3549 if (len) 3550 *len = chain->refcounted_he_val.refcounted_he_u_len; 3551 if (flags) { 3552 *flags = ((chain->refcounted_he_data[0] & HVrhek_typemask) 3553 == HVrhek_PV_UTF8) ? SVf_UTF8 : 0; 3554 } 3555 return chain->refcounted_he_data + 1; 3556 } 3557 3558 /* 3559 =for apidoc cop_store_label 3560 3561 Save a label into a C<cop_hints_hash>. 3562 You need to set flags to C<SVf_UTF8> 3563 for a utf-8 label. 3564 3565 =cut 3566 */ 3567 3568 void 3569 Perl_cop_store_label(pTHX_ COP *const cop, const char *label, STRLEN len, 3570 U32 flags) 3571 { 3572 SV *labelsv; 3573 PERL_ARGS_ASSERT_COP_STORE_LABEL; 3574 3575 if (flags & ~(SVf_UTF8)) 3576 Perl_croak(aTHX_ "panic: cop_store_label illegal flag bits 0x%" UVxf, 3577 (UV)flags); 3578 labelsv = newSVpvn_flags(label, len, SVs_TEMP); 3579 if (flags & SVf_UTF8) 3580 SvUTF8_on(labelsv); 3581 cop->cop_hints_hash 3582 = refcounted_he_new_pvs(cop->cop_hints_hash, ":", labelsv, 0); 3583 } 3584 3585 /* 3586 =for apidoc hv_assert 3587 3588 Check that a hash is in an internally consistent state. 3589 3590 =cut 3591 */ 3592 3593 #ifdef DEBUGGING 3594 3595 void 3596 Perl_hv_assert(pTHX_ HV *hv) 3597 { 3598 dVAR; 3599 HE* entry; 3600 int withflags = 0; 3601 int placeholders = 0; 3602 int real = 0; 3603 int bad = 0; 3604 const I32 riter = HvRITER_get(hv); 3605 HE *eiter = HvEITER_get(hv); 3606 3607 PERL_ARGS_ASSERT_HV_ASSERT; 3608 3609 (void)hv_iterinit(hv); 3610 3611 while ((entry = hv_iternext_flags(hv, HV_ITERNEXT_WANTPLACEHOLDERS))) { 3612 /* sanity check the values */ 3613 if (HeVAL(entry) == &PL_sv_placeholder) 3614 placeholders++; 3615 else 3616 real++; 3617 /* sanity check the keys */ 3618 if (HeSVKEY(entry)) { 3619 NOOP; /* Don't know what to check on SV keys. */ 3620 } else if (HeKUTF8(entry)) { 3621 withflags++; 3622 if (HeKWASUTF8(entry)) { 3623 PerlIO_printf(Perl_debug_log, 3624 "hash key has both WASUTF8 and UTF8: '%.*s'\n", 3625 (int) HeKLEN(entry), HeKEY(entry)); 3626 bad = 1; 3627 } 3628 } else if (HeKWASUTF8(entry)) 3629 withflags++; 3630 } 3631 if (!SvTIED_mg((const SV *)hv, PERL_MAGIC_tied)) { 3632 static const char bad_count[] = "Count %d %s(s), but hash reports %d\n"; 3633 const int nhashkeys = HvUSEDKEYS(hv); 3634 const int nhashplaceholders = HvPLACEHOLDERS_get(hv); 3635 3636 if (nhashkeys != real) { 3637 PerlIO_printf(Perl_debug_log, bad_count, real, "keys", nhashkeys ); 3638 bad = 1; 3639 } 3640 if (nhashplaceholders != placeholders) { 3641 PerlIO_printf(Perl_debug_log, bad_count, placeholders, "placeholder", nhashplaceholders ); 3642 bad = 1; 3643 } 3644 } 3645 if (withflags && ! HvHASKFLAGS(hv)) { 3646 PerlIO_printf(Perl_debug_log, 3647 "Hash has HASKFLAGS off but I count %d key(s) with flags\n", 3648 withflags); 3649 bad = 1; 3650 } 3651 if (bad) { 3652 sv_dump(MUTABLE_SV(hv)); 3653 } 3654 HvRITER_set(hv, riter); /* Restore hash iterator state */ 3655 HvEITER_set(hv, eiter); 3656 } 3657 3658 #endif 3659 3660 /* 3661 * Local variables: 3662 * c-indentation-style: bsd 3663 * c-basic-offset: 4 3664 * indent-tabs-mode: nil 3665 * End: 3666 * 3667 * ex: set ts=8 sts=4 sw=4 et: 3668 */ 3669