1 /* hv.h 2 * 3 * Copyright (C) 1991, 1992, 1993, 1996, 1997, 1998, 1999, 4 * 2000, 2001, 2002, 2003, 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 /* entry in hash value chain */ 12 struct he { 13 /* Keep hent_next first in this structure, because sv_free_arenas take 14 advantage of this to share code between the he arenas and the SV 15 body arenas */ 16 HE *hent_next; /* next entry in chain */ 17 HEK *hent_hek; /* hash key */ 18 union { 19 SV *hent_val; /* scalar value that was hashed */ 20 Size_t hent_refcount; /* references for this shared hash key */ 21 } he_valu; 22 }; 23 24 /* hash key -- defined separately for use as shared pointer */ 25 struct hek { 26 U32 hek_hash; /* hash of key */ 27 I32 hek_len; /* length of hash key */ 28 char hek_key[1]; /* variable-length hash key */ 29 /* the hash-key is \0-terminated */ 30 /* after the \0 there is a byte for flags, such as whether the key 31 is UTF-8 */ 32 }; 33 34 struct shared_he { 35 struct he shared_he_he; 36 struct hek shared_he_hek; 37 }; 38 39 /* Subject to change. 40 Don't access this directly. 41 Use the funcs in mro.c 42 */ 43 44 struct mro_alg { 45 AV *(*resolve)(pTHX_ HV* stash, U32 level); 46 const char *name; 47 U16 length; 48 U16 kflags; /* For the hash API - set HVhek_UTF8 if name is UTF-8 */ 49 U32 hash; /* or 0 */ 50 }; 51 52 struct mro_meta { 53 /* a hash holding the different MROs private data. */ 54 HV *mro_linear_all; 55 /* a pointer directly to the current MROs private data. If mro_linear_all 56 is NULL, this owns the SV reference, else it is just a pointer to a 57 value stored in and owned by mro_linear_all. */ 58 SV *mro_linear_current; 59 HV *mro_nextmethod; /* next::method caching */ 60 U32 cache_gen; /* Bumping this invalidates our method cache */ 61 U32 pkg_gen; /* Bumps when local methods/@ISA change */ 62 const struct mro_alg *mro_which; /* which mro alg is in use? */ 63 HV *isa; /* Everything this class @ISA */ 64 }; 65 66 #define MRO_GET_PRIVATE_DATA(smeta, which) \ 67 (((smeta)->mro_which && (which) == (smeta)->mro_which) \ 68 ? (smeta)->mro_linear_current \ 69 : Perl_mro_get_private_data(aTHX_ (smeta), (which))) 70 71 /* Subject to change. 72 Don't access this directly. 73 */ 74 75 struct xpvhv_aux { 76 HEK *xhv_name; /* name, if a symbol table */ 77 AV *xhv_backreferences; /* back references for weak references */ 78 HE *xhv_eiter; /* current entry of iterator */ 79 I32 xhv_riter; /* current root of iterator */ 80 struct mro_meta *xhv_mro_meta; 81 }; 82 83 /* hash structure: */ 84 /* This structure must match the beginning of struct xpvmg in sv.h. */ 85 struct xpvhv { 86 union _xnvu xnv_u; 87 STRLEN xhv_fill; /* how full xhv_array currently is */ 88 STRLEN xhv_max; /* subscript of last element of xhv_array */ 89 _XPVMG_HEAD; 90 }; 91 92 #define xhv_keys xiv_u.xivu_iv 93 94 /* hash a key */ 95 /* FYI: This is the "One-at-a-Time" algorithm by Bob Jenkins 96 * from requirements by Colin Plumb. 97 * (http://burtleburtle.net/bob/hash/doobs.html) */ 98 /* The use of a temporary pointer and the casting games 99 * is needed to serve the dual purposes of 100 * (a) the hashed data being interpreted as "unsigned char" (new since 5.8, 101 * a "char" can be either signed or unsigned, depending on the compiler) 102 * (b) catering for old code that uses a "char" 103 * 104 * The "hash seed" feature was added in Perl 5.8.1 to perturb the results 105 * to avoid "algorithmic complexity attacks". 106 * 107 * If USE_HASH_SEED is defined, hash randomisation is done by default 108 * If USE_HASH_SEED_EXPLICIT is defined, hash randomisation is done 109 * only if the environment variable PERL_HASH_SEED is set. 110 * For maximal control, one can define PERL_HASH_SEED. 111 * (see also perl.c:perl_parse()). 112 */ 113 #ifndef PERL_HASH_SEED 114 # if defined(USE_HASH_SEED) || defined(USE_HASH_SEED_EXPLICIT) 115 # define PERL_HASH_SEED PL_hash_seed 116 # else 117 # define PERL_HASH_SEED 0 118 # endif 119 #endif 120 #define PERL_HASH(hash,str,len) \ 121 STMT_START { \ 122 register const char * const s_PeRlHaSh_tmp = str; \ 123 register const unsigned char *s_PeRlHaSh = (const unsigned char *)s_PeRlHaSh_tmp; \ 124 register I32 i_PeRlHaSh = len; \ 125 register U32 hash_PeRlHaSh = PERL_HASH_SEED; \ 126 while (i_PeRlHaSh--) { \ 127 hash_PeRlHaSh += *s_PeRlHaSh++; \ 128 hash_PeRlHaSh += (hash_PeRlHaSh << 10); \ 129 hash_PeRlHaSh ^= (hash_PeRlHaSh >> 6); \ 130 } \ 131 hash_PeRlHaSh += (hash_PeRlHaSh << 3); \ 132 hash_PeRlHaSh ^= (hash_PeRlHaSh >> 11); \ 133 (hash) = (hash_PeRlHaSh + (hash_PeRlHaSh << 15)); \ 134 } STMT_END 135 136 /* Only hv.c and mod_perl should be doing this. */ 137 #ifdef PERL_HASH_INTERNAL_ACCESS 138 #define PERL_HASH_INTERNAL(hash,str,len) \ 139 STMT_START { \ 140 register const char * const s_PeRlHaSh_tmp = str; \ 141 register const unsigned char *s_PeRlHaSh = (const unsigned char *)s_PeRlHaSh_tmp; \ 142 register I32 i_PeRlHaSh = len; \ 143 register U32 hash_PeRlHaSh = PL_rehash_seed; \ 144 while (i_PeRlHaSh--) { \ 145 hash_PeRlHaSh += *s_PeRlHaSh++; \ 146 hash_PeRlHaSh += (hash_PeRlHaSh << 10); \ 147 hash_PeRlHaSh ^= (hash_PeRlHaSh >> 6); \ 148 } \ 149 hash_PeRlHaSh += (hash_PeRlHaSh << 3); \ 150 hash_PeRlHaSh ^= (hash_PeRlHaSh >> 11); \ 151 (hash) = (hash_PeRlHaSh + (hash_PeRlHaSh << 15)); \ 152 } STMT_END 153 #endif 154 155 /* 156 =head1 Hash Manipulation Functions 157 158 =for apidoc AmU||HEf_SVKEY 159 This flag, used in the length slot of hash entries and magic structures, 160 specifies the structure contains an C<SV*> pointer where a C<char*> pointer 161 is to be expected. (For information only--not to be used). 162 163 =head1 Handy Values 164 165 =for apidoc AmU||Nullhv 166 Null HV pointer. 167 168 (deprecated - use C<(HV *)NULL> instead) 169 170 =head1 Hash Manipulation Functions 171 172 =for apidoc Am|char*|HvNAME|HV* stash 173 Returns the package name of a stash, or NULL if C<stash> isn't a stash. 174 See C<SvSTASH>, C<CvSTASH>. 175 176 =for apidoc Am|void*|HeKEY|HE* he 177 Returns the actual pointer stored in the key slot of the hash entry. The 178 pointer may be either C<char*> or C<SV*>, depending on the value of 179 C<HeKLEN()>. Can be assigned to. The C<HePV()> or C<HeSVKEY()> macros are 180 usually preferable for finding the value of a key. 181 182 =for apidoc Am|STRLEN|HeKLEN|HE* he 183 If this is negative, and amounts to C<HEf_SVKEY>, it indicates the entry 184 holds an C<SV*> key. Otherwise, holds the actual length of the key. Can 185 be assigned to. The C<HePV()> macro is usually preferable for finding key 186 lengths. 187 188 =for apidoc Am|SV*|HeVAL|HE* he 189 Returns the value slot (type C<SV*>) stored in the hash entry. 190 191 =for apidoc Am|U32|HeHASH|HE* he 192 Returns the computed hash stored in the hash entry. 193 194 =for apidoc Am|char*|HePV|HE* he|STRLEN len 195 Returns the key slot of the hash entry as a C<char*> value, doing any 196 necessary dereferencing of possibly C<SV*> keys. The length of the string 197 is placed in C<len> (this is a macro, so do I<not> use C<&len>). If you do 198 not care about what the length of the key is, you may use the global 199 variable C<PL_na>, though this is rather less efficient than using a local 200 variable. Remember though, that hash keys in perl are free to contain 201 embedded nulls, so using C<strlen()> or similar is not a good way to find 202 the length of hash keys. This is very similar to the C<SvPV()> macro 203 described elsewhere in this document. See also C<HeUTF8>. 204 205 If you are using C<HePV> to get values to pass to C<newSVpvn()> to create a 206 new SV, you should consider using C<newSVhek(HeKEY_hek(he))> as it is more 207 efficient. 208 209 =for apidoc Am|char*|HeUTF8|HE* he 210 Returns whether the C<char *> value returned by C<HePV> is encoded in UTF-8, 211 doing any necessary dereferencing of possibly C<SV*> keys. The value returned 212 will be 0 or non-0, not necessarily 1 (or even a value with any low bits set), 213 so B<do not> blindly assign this to a C<bool> variable, as C<bool> may be a 214 typedef for C<char>. 215 216 =for apidoc Am|SV*|HeSVKEY|HE* he 217 Returns the key as an C<SV*>, or C<NULL> if the hash entry does not 218 contain an C<SV*> key. 219 220 =for apidoc Am|SV*|HeSVKEY_force|HE* he 221 Returns the key as an C<SV*>. Will create and return a temporary mortal 222 C<SV*> if the hash entry contains only a C<char*> key. 223 224 =for apidoc Am|SV*|HeSVKEY_set|HE* he|SV* sv 225 Sets the key to a given C<SV*>, taking care to set the appropriate flags to 226 indicate the presence of an C<SV*> key, and returns the same 227 C<SV*>. 228 229 =cut 230 */ 231 232 /* these hash entry flags ride on hent_klen (for use only in magic/tied HVs) */ 233 #define HEf_SVKEY -2 /* hent_key is an SV* */ 234 235 #ifndef PERL_CORE 236 # define Nullhv Null(HV*) 237 #endif 238 #define HvARRAY(hv) ((hv)->sv_u.svu_hash) 239 #define HvFILL(hv) ((XPVHV*) SvANY(hv))->xhv_fill 240 #define HvMAX(hv) ((XPVHV*) SvANY(hv))->xhv_max 241 /* This quite intentionally does no flag checking first. That's your 242 responsibility. */ 243 #define HvAUX(hv) ((struct xpvhv_aux*)&(HvARRAY(hv)[HvMAX(hv)+1])) 244 #define HvRITER(hv) (*Perl_hv_riter_p(aTHX_ MUTABLE_HV(hv))) 245 #define HvEITER(hv) (*Perl_hv_eiter_p(aTHX_ MUTABLE_HV(hv))) 246 #define HvRITER_set(hv,r) Perl_hv_riter_set(aTHX_ MUTABLE_HV(hv), r) 247 #define HvEITER_set(hv,e) Perl_hv_eiter_set(aTHX_ MUTABLE_HV(hv), e) 248 #define HvRITER_get(hv) (SvOOK(hv) ? HvAUX(hv)->xhv_riter : -1) 249 #define HvEITER_get(hv) (SvOOK(hv) ? HvAUX(hv)->xhv_eiter : NULL) 250 #define HvNAME(hv) HvNAME_get(hv) 251 252 /* Checking that hv is a valid package stash is the 253 caller's responsibility */ 254 #define HvMROMETA(hv) (HvAUX(hv)->xhv_mro_meta \ 255 ? HvAUX(hv)->xhv_mro_meta \ 256 : Perl_mro_meta_init(aTHX_ hv)) 257 258 /* FIXME - all of these should use a UTF8 aware API, which should also involve 259 getting the length. */ 260 /* This macro may go away without notice. */ 261 #define HvNAME_HEK(hv) (SvOOK(hv) ? HvAUX(hv)->xhv_name : NULL) 262 #define HvNAME_get(hv) ((SvOOK(hv) && (HvAUX(hv)->xhv_name)) \ 263 ? HEK_KEY(HvAUX(hv)->xhv_name) : NULL) 264 #define HvNAMELEN_get(hv) ((SvOOK(hv) && (HvAUX(hv)->xhv_name)) \ 265 ? HEK_LEN(HvAUX(hv)->xhv_name) : 0) 266 267 /* the number of keys (including any placeholers) */ 268 #define XHvTOTALKEYS(xhv) ((xhv)->xhv_keys) 269 270 /* 271 * HvKEYS gets the number of keys that actually exist(), and is provided 272 * for backwards compatibility with old XS code. The core uses HvUSEDKEYS 273 * (keys, excluding placeholdes) and HvTOTALKEYS (including placeholders) 274 */ 275 #define HvKEYS(hv) HvUSEDKEYS(hv) 276 #define HvUSEDKEYS(hv) (HvTOTALKEYS(hv) - HvPLACEHOLDERS_get(hv)) 277 #define HvTOTALKEYS(hv) XHvTOTALKEYS((XPVHV*) SvANY(hv)) 278 #define HvPLACEHOLDERS(hv) (*Perl_hv_placeholders_p(aTHX_ MUTABLE_HV(hv))) 279 #define HvPLACEHOLDERS_get(hv) (SvMAGIC(hv) ? Perl_hv_placeholders_get(aTHX_ (const HV *)hv) : 0) 280 #define HvPLACEHOLDERS_set(hv,p) Perl_hv_placeholders_set(aTHX_ MUTABLE_HV(hv), p) 281 282 #define HvSHAREKEYS(hv) (SvFLAGS(hv) & SVphv_SHAREKEYS) 283 #define HvSHAREKEYS_on(hv) (SvFLAGS(hv) |= SVphv_SHAREKEYS) 284 #define HvSHAREKEYS_off(hv) (SvFLAGS(hv) &= ~SVphv_SHAREKEYS) 285 286 /* This is an optimisation flag. It won't be set if all hash keys have a 0 287 * flag. Currently the only flags relate to utf8. 288 * Hence it won't be set if all keys are 8 bit only. It will be set if any key 289 * is utf8 (including 8 bit keys that were entered as utf8, and need upgrading 290 * when retrieved during iteration. It may still be set when there are no longer 291 * any utf8 keys. 292 * See HVhek_ENABLEHVKFLAGS for the trigger. 293 */ 294 #define HvHASKFLAGS(hv) (SvFLAGS(hv) & SVphv_HASKFLAGS) 295 #define HvHASKFLAGS_on(hv) (SvFLAGS(hv) |= SVphv_HASKFLAGS) 296 #define HvHASKFLAGS_off(hv) (SvFLAGS(hv) &= ~SVphv_HASKFLAGS) 297 298 #define HvLAZYDEL(hv) (SvFLAGS(hv) & SVphv_LAZYDEL) 299 #define HvLAZYDEL_on(hv) (SvFLAGS(hv) |= SVphv_LAZYDEL) 300 #define HvLAZYDEL_off(hv) (SvFLAGS(hv) &= ~SVphv_LAZYDEL) 301 302 #define HvREHASH(hv) (SvFLAGS(hv) & SVphv_REHASH) 303 #define HvREHASH_on(hv) (SvFLAGS(hv) |= SVphv_REHASH) 304 #define HvREHASH_off(hv) (SvFLAGS(hv) &= ~SVphv_REHASH) 305 306 #ifndef PERL_CORE 307 # define Nullhe Null(HE*) 308 #endif 309 #define HeNEXT(he) (he)->hent_next 310 #define HeKEY_hek(he) (he)->hent_hek 311 #define HeKEY(he) HEK_KEY(HeKEY_hek(he)) 312 #define HeKEY_sv(he) (*(SV**)HeKEY(he)) 313 #define HeKLEN(he) HEK_LEN(HeKEY_hek(he)) 314 #define HeKUTF8(he) HEK_UTF8(HeKEY_hek(he)) 315 #define HeKWASUTF8(he) HEK_WASUTF8(HeKEY_hek(he)) 316 #define HeKREHASH(he) HEK_REHASH(HeKEY_hek(he)) 317 #define HeKLEN_UTF8(he) (HeKUTF8(he) ? -HeKLEN(he) : HeKLEN(he)) 318 #define HeKFLAGS(he) HEK_FLAGS(HeKEY_hek(he)) 319 #define HeVAL(he) (he)->he_valu.hent_val 320 #define HeHASH(he) HEK_HASH(HeKEY_hek(he)) 321 #define HePV(he,lp) ((HeKLEN(he) == HEf_SVKEY) ? \ 322 SvPV(HeKEY_sv(he),lp) : \ 323 ((lp = HeKLEN(he)), HeKEY(he))) 324 #define HeUTF8(he) ((HeKLEN(he) == HEf_SVKEY) ? \ 325 SvUTF8(HeKEY_sv(he)) : \ 326 (U32)HeKUTF8(he)) 327 328 #define HeSVKEY(he) ((HeKEY(he) && \ 329 HeKLEN(he) == HEf_SVKEY) ? \ 330 HeKEY_sv(he) : NULL) 331 332 #define HeSVKEY_force(he) (HeKEY(he) ? \ 333 ((HeKLEN(he) == HEf_SVKEY) ? \ 334 HeKEY_sv(he) : \ 335 newSVpvn_flags(HeKEY(he), \ 336 HeKLEN(he), SVs_TEMP)) : \ 337 &PL_sv_undef) 338 #define HeSVKEY_set(he,sv) ((HeKLEN(he) = HEf_SVKEY), (HeKEY_sv(he) = sv)) 339 340 #ifndef PERL_CORE 341 # define Nullhek Null(HEK*) 342 #endif 343 #define HEK_BASESIZE STRUCT_OFFSET(HEK, hek_key[0]) 344 #define HEK_HASH(hek) (hek)->hek_hash 345 #define HEK_LEN(hek) (hek)->hek_len 346 #define HEK_KEY(hek) (hek)->hek_key 347 #define HEK_FLAGS(hek) (*((unsigned char *)(HEK_KEY(hek))+HEK_LEN(hek)+1)) 348 349 #define HVhek_UTF8 0x01 /* Key is utf8 encoded. */ 350 #define HVhek_WASUTF8 0x02 /* Key is bytes here, but was supplied as utf8. */ 351 #define HVhek_REHASH 0x04 /* This key is in an hv using a custom HASH . */ 352 #define HVhek_UNSHARED 0x08 /* This key isn't a shared hash key. */ 353 #define HVhek_FREEKEY 0x100 /* Internal flag to say key is malloc()ed. */ 354 #define HVhek_PLACEHOLD 0x200 /* Internal flag to create placeholder. 355 * (may change, but Storable is a core module) */ 356 #define HVhek_KEYCANONICAL 0x400 /* Internal flag - key is in canonical form. 357 If the string is UTF-8, it cannot be 358 converted to bytes. */ 359 #define HVhek_MASK 0xFF 360 361 /* Which flags enable HvHASKFLAGS? Somewhat a hack on a hack, as 362 HVhek_REHASH is only needed because the rehash flag has to be duplicated 363 into all keys as hv_iternext has no access to the hash flags. At this 364 point Storable's tests get upset, because sometimes hashes are "keyed" 365 and sometimes not, depending on the order of data insertion, and whether 366 it triggered rehashing. So currently HVhek_REHASH is exempt. 367 Similarly UNSHARED 368 */ 369 370 #define HVhek_ENABLEHVKFLAGS (HVhek_MASK & ~(HVhek_REHASH|HVhek_UNSHARED)) 371 372 #define HEK_UTF8(hek) (HEK_FLAGS(hek) & HVhek_UTF8) 373 #define HEK_UTF8_on(hek) (HEK_FLAGS(hek) |= HVhek_UTF8) 374 #define HEK_UTF8_off(hek) (HEK_FLAGS(hek) &= ~HVhek_UTF8) 375 #define HEK_WASUTF8(hek) (HEK_FLAGS(hek) & HVhek_WASUTF8) 376 #define HEK_WASUTF8_on(hek) (HEK_FLAGS(hek) |= HVhek_WASUTF8) 377 #define HEK_WASUTF8_off(hek) (HEK_FLAGS(hek) &= ~HVhek_WASUTF8) 378 #define HEK_REHASH(hek) (HEK_FLAGS(hek) & HVhek_REHASH) 379 #define HEK_REHASH_on(hek) (HEK_FLAGS(hek) |= HVhek_REHASH) 380 381 /* calculate HV array allocation */ 382 #ifndef PERL_USE_LARGE_HV_ALLOC 383 /* Default to allocating the correct size - default to assuming that malloc() 384 is not broken and is efficient at allocating blocks sized at powers-of-two. 385 */ 386 # define PERL_HV_ARRAY_ALLOC_BYTES(size) ((size) * sizeof(HE*)) 387 #else 388 # define MALLOC_OVERHEAD 16 389 # define PERL_HV_ARRAY_ALLOC_BYTES(size) \ 390 (((size) < 64) \ 391 ? (size) * sizeof(HE*) \ 392 : (size) * sizeof(HE*) * 2 - MALLOC_OVERHEAD) 393 #endif 394 395 /* Flags for hv_iternext_flags. */ 396 #define HV_ITERNEXT_WANTPLACEHOLDERS 0x01 /* Don't skip placeholders. */ 397 398 #define hv_iternext(hv) hv_iternext_flags(hv, 0) 399 #define hv_magic(hv, gv, how) sv_magic(MUTABLE_SV(hv), MUTABLE_SV(gv), how, NULL, 0) 400 401 /* available as a function in hv.c */ 402 #define Perl_sharepvn(sv, len, hash) HEK_KEY(share_hek(sv, len, hash)) 403 #define sharepvn(sv, len, hash) Perl_sharepvn(sv, len, hash) 404 405 #define share_hek_hek(hek) \ 406 (++(((struct shared_he *)(((char *)hek) \ 407 - STRUCT_OFFSET(struct shared_he, \ 408 shared_he_hek))) \ 409 ->shared_he_he.he_valu.hent_refcount), \ 410 hek) 411 412 #define hv_store_ent(hv, keysv, val, hash) \ 413 ((HE *) hv_common((hv), (keysv), NULL, 0, 0, HV_FETCH_ISSTORE, \ 414 (val), (hash))) 415 416 #define hv_exists_ent(hv, keysv, hash) \ 417 (hv_common((hv), (keysv), NULL, 0, 0, HV_FETCH_ISEXISTS, 0, (hash)) \ 418 ? TRUE : FALSE) 419 #define hv_fetch_ent(hv, keysv, lval, hash) \ 420 ((HE *) hv_common((hv), (keysv), NULL, 0, 0, \ 421 ((lval) ? HV_FETCH_LVALUE : 0), NULL, (hash))) 422 #define hv_delete_ent(hv, key, flags, hash) \ 423 (MUTABLE_SV(hv_common((hv), (key), NULL, 0, 0, (flags) | HV_DELETE, \ 424 NULL, (hash)))) 425 426 #define hv_store_flags(hv, key, klen, val, hash, flags) \ 427 ((SV**) hv_common((hv), NULL, (key), (klen), (flags), \ 428 (HV_FETCH_ISSTORE|HV_FETCH_JUST_SV), (val), \ 429 (hash))) 430 431 #define hv_store(hv, key, klen, val, hash) \ 432 ((SV**) hv_common_key_len((hv), (key), (klen), \ 433 (HV_FETCH_ISSTORE|HV_FETCH_JUST_SV), \ 434 (val), (hash))) 435 436 #define hv_exists(hv, key, klen) \ 437 (hv_common_key_len((hv), (key), (klen), HV_FETCH_ISEXISTS, NULL, 0) \ 438 ? TRUE : FALSE) 439 440 #define hv_fetch(hv, key, klen, lval) \ 441 ((SV**) hv_common_key_len((hv), (key), (klen), (lval) \ 442 ? (HV_FETCH_JUST_SV | HV_FETCH_LVALUE) \ 443 : HV_FETCH_JUST_SV, NULL, 0)) 444 445 #define hv_delete(hv, key, klen, flags) \ 446 (MUTABLE_SV(hv_common_key_len((hv), (key), (klen), \ 447 (flags) | HV_DELETE, NULL, 0))) 448 449 /* This refcounted he structure is used for storing the hints used for lexical 450 pragmas. Without threads, it's basically struct he + refcount. 451 With threads, life gets more complex as the structure needs to be shared 452 between threads (because it hangs from OPs, which are shared), hence the 453 alternate definition and mutex. */ 454 455 struct refcounted_he; 456 457 #ifdef PERL_CORE 458 459 /* Gosh. This really isn't a good name any longer. */ 460 struct refcounted_he { 461 struct refcounted_he *refcounted_he_next; /* next entry in chain */ 462 #ifdef USE_ITHREADS 463 U32 refcounted_he_hash; 464 U32 refcounted_he_keylen; 465 #else 466 HEK *refcounted_he_hek; /* hint key */ 467 #endif 468 union { 469 IV refcounted_he_u_iv; 470 UV refcounted_he_u_uv; 471 STRLEN refcounted_he_u_len; 472 void *refcounted_he_u_ptr; /* Might be useful in future */ 473 } refcounted_he_val; 474 U32 refcounted_he_refcnt; /* reference count */ 475 /* First byte is flags. Then NUL-terminated value. Then for ithreads, 476 non-NUL terminated key. */ 477 char refcounted_he_data[1]; 478 }; 479 480 /* Flag bits are HVhek_UTF8, HVhek_WASUTF8, then */ 481 #define HVrhek_undef 0x00 /* Value is undef. */ 482 #define HVrhek_delete 0x10 /* Value is placeholder - signifies delete. */ 483 #define HVrhek_IV 0x20 /* Value is IV. */ 484 #define HVrhek_UV 0x30 /* Value is UV. */ 485 #define HVrhek_PV 0x40 /* Value is a (byte) string. */ 486 #define HVrhek_PV_UTF8 0x50 /* Value is a (utf8) string. */ 487 /* Two spare. As these have to live in the optree, you can't store anything 488 interpreter specific, such as SVs. :-( */ 489 #define HVrhek_typemask 0x70 490 491 #ifdef USE_ITHREADS 492 /* A big expression to find the key offset */ 493 #define REF_HE_KEY(chain) \ 494 ((((chain->refcounted_he_data[0] & 0x60) == 0x40) \ 495 ? chain->refcounted_he_val.refcounted_he_u_len + 1 : 0) \ 496 + 1 + chain->refcounted_he_data) 497 #endif 498 499 # ifdef USE_ITHREADS 500 # define HINTS_REFCNT_LOCK MUTEX_LOCK(&PL_hints_mutex) 501 # define HINTS_REFCNT_UNLOCK MUTEX_UNLOCK(&PL_hints_mutex) 502 # else 503 # define HINTS_REFCNT_LOCK NOOP 504 # define HINTS_REFCNT_UNLOCK NOOP 505 # endif 506 #endif 507 508 #ifdef USE_ITHREADS 509 # define HINTS_REFCNT_INIT MUTEX_INIT(&PL_hints_mutex) 510 # define HINTS_REFCNT_TERM MUTEX_DESTROY(&PL_hints_mutex) 511 #else 512 # define HINTS_REFCNT_INIT NOOP 513 # define HINTS_REFCNT_TERM NOOP 514 #endif 515 516 /* Hash actions 517 * Passed in PERL_MAGIC_uvar calls 518 */ 519 #define HV_DISABLE_UVAR_XKEY 0x01 520 /* We need to ensure that these don't clash with G_DISCARD, which is 2, as it 521 is documented as being passed to hv_delete(). */ 522 #define HV_FETCH_ISSTORE 0x04 523 #define HV_FETCH_ISEXISTS 0x08 524 #define HV_FETCH_LVALUE 0x10 525 #define HV_FETCH_JUST_SV 0x20 526 #define HV_DELETE 0x40 527 528 /* 529 =for apidoc newHV 530 531 Creates a new HV. The reference count is set to 1. 532 533 =cut 534 */ 535 536 #define newHV() MUTABLE_HV(newSV_type(SVt_PVHV)) 537 538 /* 539 * Local variables: 540 * c-indentation-style: bsd 541 * c-basic-offset: 4 542 * indent-tabs-mode: t 543 * End: 544 * 545 * ex: set ts=8 sts=4 sw=4 noet: 546 */ 547