3 * Copyright (c) 1991-1997, Larry Wall
5 * You may distribute under the terms of either the GNU General Public
6 * License or the Artistic License, as specified in the README file.
11 * "I sit beside the fire and think of all that I have seen." --Bilbo
17 static void hsplit _((HV *hv));
18 static void hfreeentries _((HV *hv));
20 static HE* more_he(void);
37 HeNEXT(p) = (HE*)he_root;
46 he_root = (HE*)safemalloc(1008);
48 heend = &he[1008 / sizeof(HE) - 1];
50 HeNEXT(he) = (HE*)(he + 1);
58 save_hek(char *str, I32 len, U32 hash)
63 New(54, k, HEK_BASESIZE + len + 1, char);
65 Copy(str, HEK_KEY(hek), len, char);
66 *(HEK_KEY(hek) + len) = '\0';
75 unsharepvn(HEK_KEY(hek),HEK_LEN(hek),HEK_HASH(hek));
78 /* (klen == HEf_SVKEY) is special for MAGICAL hv entries, meaning key slot
82 hv_fetch(HV *hv, char *key, U32 klen, I32 lval)
93 if (mg_find((SV*)hv,'P')) {
96 mg_copy((SV*)hv, sv, key, klen);
102 xhv = (XPVHV*)SvANY(hv);
103 if (!xhv->xhv_array) {
105 #ifdef DYNAMIC_ENV_FETCH /* if it's an %ENV lookup, we may get it on the fly */
106 || (HvNAME(hv) && strEQ(HvNAME(hv),ENV_HV_NAME))
109 Newz(503,xhv->xhv_array, sizeof(HE*) * (xhv->xhv_max + 1), char);
114 PERL_HASH(hash, key, klen);
116 entry = ((HE**)xhv->xhv_array)[hash & (I32) xhv->xhv_max];
117 for (; entry; entry = HeNEXT(entry)) {
118 if (HeHASH(entry) != hash) /* strings can't be equal */
120 if (HeKLEN(entry) != klen)
122 if (memNE(HeKEY(entry),key,klen)) /* is this it? */
124 return &HeVAL(entry);
126 #ifdef DYNAMIC_ENV_FETCH /* %ENV lookup? If so, try to fetch the value now */
127 if (HvNAME(hv) && strEQ(HvNAME(hv),ENV_HV_NAME)) {
130 if ((gotenv = ENV_getenv(key)) != Nullch) {
131 sv = newSVpv(gotenv,strlen(gotenv));
133 return hv_store(hv,key,klen,sv,hash);
137 if (lval) { /* gonna assign to this, so it better be there */
139 return hv_store(hv,key,klen,sv,hash);
144 /* returns a HE * structure with the all fields set */
145 /* note that hent_val will be a mortal sv for MAGICAL hashes */
147 hv_fetch_ent(HV *hv, SV *keysv, I32 lval, register U32 hash)
158 if (SvRMAGICAL(hv) && mg_find((SV*)hv,'P')) {
162 keysv = sv_2mortal(newSVsv(keysv));
163 mg_copy((SV*)hv, sv, (char*)keysv, HEf_SVKEY);
164 if (!HeKEY_hek(&mh)) {
166 New(54, k, HEK_BASESIZE + sizeof(SV*), char);
167 HeKEY_hek(&mh) = (HEK*)k;
169 HeSVKEY_set(&mh, keysv);
174 xhv = (XPVHV*)SvANY(hv);
175 if (!xhv->xhv_array) {
177 #ifdef DYNAMIC_ENV_FETCH /* if it's an %ENV lookup, we may get it on the fly */
178 || (HvNAME(hv) && strEQ(HvNAME(hv),ENV_HV_NAME))
181 Newz(503,xhv->xhv_array, sizeof(HE*) * (xhv->xhv_max + 1), char);
186 key = SvPV(keysv, klen);
189 PERL_HASH(hash, key, klen);
191 entry = ((HE**)xhv->xhv_array)[hash & (I32) xhv->xhv_max];
192 for (; entry; entry = HeNEXT(entry)) {
193 if (HeHASH(entry) != hash) /* strings can't be equal */
195 if (HeKLEN(entry) != klen)
197 if (memNE(HeKEY(entry),key,klen)) /* is this it? */
201 #ifdef DYNAMIC_ENV_FETCH /* %ENV lookup? If so, try to fetch the value now */
202 if (HvNAME(hv) && strEQ(HvNAME(hv),ENV_HV_NAME)) {
205 if ((gotenv = ENV_getenv(key)) != Nullch) {
206 sv = newSVpv(gotenv,strlen(gotenv));
208 return hv_store_ent(hv,keysv,sv,hash);
212 if (lval) { /* gonna assign to this, so it better be there */
214 return hv_store_ent(hv,keysv,sv,hash);
220 hv_magic_check (hv, needs_copy, needs_store)
225 MAGIC *mg = SvMAGIC(hv);
229 if (isUPPER(mg->mg_type)) {
231 switch (mg->mg_type) {
235 *needs_store = FALSE;
238 mg = mg->mg_moremagic;
243 hv_store(HV *hv, char *key, U32 klen, SV *val, register U32 hash)
248 register HE **oentry;
253 xhv = (XPVHV*)SvANY(hv);
257 hv_magic_check (hv, &needs_copy, &needs_store);
259 mg_copy((SV*)hv, val, key, klen);
260 if (!xhv->xhv_array && !needs_store)
265 PERL_HASH(hash, key, klen);
268 Newz(505, xhv->xhv_array, sizeof(HE**) * (xhv->xhv_max + 1), char);
270 oentry = &((HE**)xhv->xhv_array)[hash & (I32) xhv->xhv_max];
273 for (entry = *oentry; entry; i=0, entry = HeNEXT(entry)) {
274 if (HeHASH(entry) != hash) /* strings can't be equal */
276 if (HeKLEN(entry) != klen)
278 if (memNE(HeKEY(entry),key,klen)) /* is this it? */
280 SvREFCNT_dec(HeVAL(entry));
282 return &HeVAL(entry);
287 HeKEY_hek(entry) = share_hek(key, klen, hash);
288 else /* gotta do the real thing */
289 HeKEY_hek(entry) = save_hek(key, klen, hash);
291 HeNEXT(entry) = *oentry;
295 if (i) { /* initial entry? */
297 if (xhv->xhv_keys > xhv->xhv_max)
301 return &HeVAL(entry);
305 hv_store_ent(HV *hv, SV *keysv, SV *val, register U32 hash)
312 register HE **oentry;
317 xhv = (XPVHV*)SvANY(hv);
322 hv_magic_check (hv, &needs_copy, &needs_store);
324 bool save_taint = tainted;
326 tainted = SvTAINTED(keysv);
327 keysv = sv_2mortal(newSVsv(keysv));
328 mg_copy((SV*)hv, val, (char*)keysv, HEf_SVKEY);
329 TAINT_IF(save_taint);
330 if (!xhv->xhv_array && !needs_store)
335 key = SvPV(keysv, klen);
338 PERL_HASH(hash, key, klen);
341 Newz(505, xhv->xhv_array, sizeof(HE**) * (xhv->xhv_max + 1), char);
343 oentry = &((HE**)xhv->xhv_array)[hash & (I32) xhv->xhv_max];
346 for (entry = *oentry; entry; i=0, entry = HeNEXT(entry)) {
347 if (HeHASH(entry) != hash) /* strings can't be equal */
349 if (HeKLEN(entry) != klen)
351 if (memNE(HeKEY(entry),key,klen)) /* is this it? */
353 SvREFCNT_dec(HeVAL(entry));
360 HeKEY_hek(entry) = share_hek(key, klen, hash);
361 else /* gotta do the real thing */
362 HeKEY_hek(entry) = save_hek(key, klen, hash);
364 HeNEXT(entry) = *oentry;
368 if (i) { /* initial entry? */
370 if (xhv->xhv_keys > xhv->xhv_max)
378 hv_delete(HV *hv, char *key, U32 klen, I32 flags)
384 register HE **oentry;
389 if (SvRMAGICAL(hv)) {
390 sv = *hv_fetch(hv, key, klen, TRUE);
392 if (mg_find(sv, 's')) {
393 return Nullsv; /* %SIG elements cannot be deleted */
395 if (mg_find(sv, 'p')) {
396 sv_unmagic(sv, 'p'); /* No longer an element */
400 xhv = (XPVHV*)SvANY(hv);
404 PERL_HASH(hash, key, klen);
406 oentry = &((HE**)xhv->xhv_array)[hash & (I32) xhv->xhv_max];
409 for (; entry; i=0, oentry = &HeNEXT(entry), entry = *oentry) {
410 if (HeHASH(entry) != hash) /* strings can't be equal */
412 if (HeKLEN(entry) != klen)
414 if (memNE(HeKEY(entry),key,klen)) /* is this it? */
416 *oentry = HeNEXT(entry);
419 if (flags & G_DISCARD)
422 sv = sv_mortalcopy(HeVAL(entry));
423 if (entry == xhv->xhv_eiter)
426 hv_free_ent(hv, entry);
434 hv_delete_ent(HV *hv, SV *keysv, I32 flags, U32 hash)
441 register HE **oentry;
446 if (SvRMAGICAL(hv)) {
447 entry = hv_fetch_ent(hv, keysv, TRUE, hash);
450 if (mg_find(sv, 'p')) {
451 sv_unmagic(sv, 'p'); /* No longer an element */
455 xhv = (XPVHV*)SvANY(hv);
459 key = SvPV(keysv, klen);
462 PERL_HASH(hash, key, klen);
464 oentry = &((HE**)xhv->xhv_array)[hash & (I32) xhv->xhv_max];
467 for (; entry; i=0, oentry = &HeNEXT(entry), entry = *oentry) {
468 if (HeHASH(entry) != hash) /* strings can't be equal */
470 if (HeKLEN(entry) != klen)
472 if (memNE(HeKEY(entry),key,klen)) /* is this it? */
474 *oentry = HeNEXT(entry);
477 if (flags & G_DISCARD)
480 sv = sv_mortalcopy(HeVAL(entry));
481 if (entry == xhv->xhv_eiter)
484 hv_free_ent(hv, entry);
492 hv_exists(HV *hv, char *key, U32 klen)
502 if (SvRMAGICAL(hv)) {
503 if (mg_find((SV*)hv,'P')) {
506 mg_copy((SV*)hv, sv, key, klen);
507 magic_existspack(sv, mg_find(sv, 'p'));
512 xhv = (XPVHV*)SvANY(hv);
516 PERL_HASH(hash, key, klen);
518 entry = ((HE**)xhv->xhv_array)[hash & (I32) xhv->xhv_max];
519 for (; entry; entry = HeNEXT(entry)) {
520 if (HeHASH(entry) != hash) /* strings can't be equal */
522 if (HeKLEN(entry) != klen)
524 if (memNE(HeKEY(entry),key,klen)) /* is this it? */
533 hv_exists_ent(HV *hv, SV *keysv, U32 hash)
544 if (SvRMAGICAL(hv)) {
545 if (mg_find((SV*)hv,'P')) {
546 dTHR; /* just for SvTRUE */
548 keysv = sv_2mortal(newSVsv(keysv));
549 mg_copy((SV*)hv, sv, (char*)keysv, HEf_SVKEY);
550 magic_existspack(sv, mg_find(sv, 'p'));
555 xhv = (XPVHV*)SvANY(hv);
559 key = SvPV(keysv, klen);
561 PERL_HASH(hash, key, klen);
563 entry = ((HE**)xhv->xhv_array)[hash & (I32) xhv->xhv_max];
564 for (; entry; entry = HeNEXT(entry)) {
565 if (HeHASH(entry) != hash) /* strings can't be equal */
567 if (HeKLEN(entry) != klen)
569 if (memNE(HeKEY(entry),key,klen)) /* is this it? */
579 register XPVHV* xhv = (XPVHV*)SvANY(hv);
580 I32 oldsize = (I32) xhv->xhv_max + 1; /* sic(k) */
581 register I32 newsize = oldsize * 2;
586 register HE **oentry;
587 #ifndef STRANGE_MALLOC
591 a = (HE**)xhv->xhv_array;
593 #ifdef STRANGE_MALLOC
594 Renew(a, newsize, HE*);
596 i = newsize * sizeof(HE*);
597 #define MALLOC_OVERHEAD 16
598 tmp = MALLOC_OVERHEAD;
599 while (tmp - MALLOC_OVERHEAD < i)
601 tmp -= MALLOC_OVERHEAD;
603 assert(tmp >= newsize);
605 Copy(xhv->xhv_array, a, oldsize, HE*);
607 offer_nice_chunk(xhv->xhv_array,
608 oldsize * sizeof(HE*) * 2 - MALLOC_OVERHEAD);
611 Safefree(xhv->xhv_array);
615 Zero(&a[oldsize], oldsize, HE*); /* zero 2nd half*/
616 xhv->xhv_max = --newsize;
617 xhv->xhv_array = (char*)a;
619 for (i=0; i<oldsize; i++,a++) {
620 if (!*a) /* non-existent */
623 for (oentry = a, entry = *a; entry; entry = *oentry) {
624 if ((HeHASH(entry) & newsize) != i) {
625 *oentry = HeNEXT(entry);
633 oentry = &HeNEXT(entry);
635 if (!*a) /* everything moved */
641 hv_ksplit(HV *hv, IV newmax)
643 register XPVHV* xhv = (XPVHV*)SvANY(hv);
644 I32 oldsize = (I32) xhv->xhv_max + 1; /* sic(k) */
645 register I32 newsize;
650 register HE **oentry;
652 newsize = (I32) newmax; /* possible truncation here */
653 if (newsize != newmax || newmax <= oldsize)
655 while ((newsize & (1 + ~newsize)) != newsize) {
656 newsize &= ~(newsize & (1 + ~newsize)); /* get proper power of 2 */
658 if (newsize < newmax)
660 if (newsize < newmax)
661 return; /* overflow detection */
663 a = (HE**)xhv->xhv_array;
666 #ifdef STRANGE_MALLOC
667 Renew(a, newsize, HE*);
669 i = newsize * sizeof(HE*);
671 while (j - MALLOC_OVERHEAD < i)
673 j -= MALLOC_OVERHEAD;
675 assert(j >= newsize);
677 Copy(xhv->xhv_array, a, oldsize, HE*);
679 offer_nice_chunk(xhv->xhv_array,
680 oldsize * sizeof(HE*) * 2 - MALLOC_OVERHEAD);
683 Safefree(xhv->xhv_array);
686 Zero(&a[oldsize], newsize-oldsize, HE*); /* zero 2nd half*/
689 Newz(0, a, newsize, HE*);
691 xhv->xhv_max = --newsize;
692 xhv->xhv_array = (char*)a;
693 if (!xhv->xhv_fill) /* skip rest if no entries */
696 for (i=0; i<oldsize; i++,a++) {
697 if (!*a) /* non-existent */
699 for (oentry = a, entry = *a; entry; entry = *oentry) {
700 if ((j = (HeHASH(entry) & newsize)) != i) {
702 *oentry = HeNEXT(entry);
703 if (!(HeNEXT(entry) = a[j]))
709 oentry = &HeNEXT(entry);
711 if (!*a) /* everything moved */
722 hv = (HV*)NEWSV(502,0);
723 sv_upgrade((SV *)hv, SVt_PVHV);
724 xhv = (XPVHV*)SvANY(hv);
727 #ifndef NODEFAULT_SHAREKEYS
728 HvSHAREKEYS_on(hv); /* key-sharing on by default */
730 xhv->xhv_max = 7; /* start with 8 buckets */
733 (void)hv_iterinit(hv); /* so each() will start off right */
738 hv_free_ent(HV *hv, register HE *entry)
742 if (isGV(HeVAL(entry)) && GvCVu(HeVAL(entry)) && HvNAME(hv))
743 sub_generation++; /* may be deletion of method from stash */
744 SvREFCNT_dec(HeVAL(entry));
745 if (HeKLEN(entry) == HEf_SVKEY) {
746 SvREFCNT_dec(HeKEY_sv(entry));
747 Safefree(HeKEY_hek(entry));
749 else if (HvSHAREKEYS(hv))
750 unshare_hek(HeKEY_hek(entry));
752 Safefree(HeKEY_hek(entry));
757 hv_delayfree_ent(HV *hv, register HE *entry)
761 if (isGV(HeVAL(entry)) && GvCVu(HeVAL(entry)) && HvNAME(hv))
762 sub_generation++; /* may be deletion of method from stash */
763 sv_2mortal(HeVAL(entry)); /* free between statements */
764 if (HeKLEN(entry) == HEf_SVKEY) {
765 sv_2mortal(HeKEY_sv(entry));
766 Safefree(HeKEY_hek(entry));
768 else if (HvSHAREKEYS(hv))
769 unshare_hek(HeKEY_hek(entry));
771 Safefree(HeKEY_hek(entry));
781 xhv = (XPVHV*)SvANY(hv);
786 (void)memzero(xhv->xhv_array, (xhv->xhv_max + 1) * sizeof(HE*));
797 register HE *oentry = Null(HE*);
813 entry = HeNEXT(entry);
814 hv_free_ent(hv, oentry);
819 entry = array[riter];
822 (void)hv_iterinit(hv);
831 xhv = (XPVHV*)SvANY(hv);
833 Safefree(xhv->xhv_array);
835 Safefree(HvNAME(hv));
839 xhv->xhv_max = 7; /* it's a normal hash */
855 xhv = (XPVHV*)SvANY(hv);
856 entry = xhv->xhv_eiter;
857 #ifdef DYNAMIC_ENV_FETCH /* set up %ENV for iteration */
858 if (HvNAME(hv) && strEQ(HvNAME(hv), ENV_HV_NAME))
861 if (entry && HvLAZYDEL(hv)) { /* was deleted earlier? */
863 hv_free_ent(hv, entry);
866 xhv->xhv_eiter = Null(HE*);
867 return xhv->xhv_fill; /* should be xhv->xhv_keys? May change later */
880 xhv = (XPVHV*)SvANY(hv);
881 oldentry = entry = xhv->xhv_eiter;
883 if (SvRMAGICAL(hv) && (mg = mg_find((SV*)hv,'P'))) {
884 SV *key = sv_newmortal();
886 sv_setsv(key, HeSVKEY_force(entry));
887 SvREFCNT_dec(HeSVKEY(entry)); /* get rid of previous key */
893 xhv->xhv_eiter = entry = new_he(); /* one HE per MAGICAL hash */
895 Newz(54, k, HEK_BASESIZE + sizeof(SV*), char);
897 HeKEY_hek(entry) = hek;
898 HeKLEN(entry) = HEf_SVKEY;
900 magic_nextpack((SV*) hv,mg,key);
902 /* force key to stay around until next time */
903 HeSVKEY_set(entry, SvREFCNT_inc(key));
904 return entry; /* beware, hent_val is not set */
907 SvREFCNT_dec(HeVAL(entry));
908 Safefree(HeKEY_hek(entry));
910 xhv->xhv_eiter = Null(HE*);
915 Newz(506,xhv->xhv_array, sizeof(HE*) * (xhv->xhv_max + 1), char);
917 entry = HeNEXT(entry);
920 if (xhv->xhv_riter > xhv->xhv_max) {
924 entry = ((HE**)xhv->xhv_array)[xhv->xhv_riter];
927 if (oldentry && HvLAZYDEL(hv)) { /* was deleted earlier? */
929 hv_free_ent(hv, oldentry);
932 xhv->xhv_eiter = entry;
937 hv_iterkey(register HE *entry, I32 *retlen)
939 if (HeKLEN(entry) == HEf_SVKEY) {
941 char *p = SvPV(HeKEY_sv(entry), len);
946 *retlen = HeKLEN(entry);
951 /* unlike hv_iterval(), this always returns a mortal copy of the key */
953 hv_iterkeysv(register HE *entry)
955 if (HeKLEN(entry) == HEf_SVKEY)
956 return sv_mortalcopy(HeKEY_sv(entry));
958 return sv_2mortal(newSVpv((HeKLEN(entry) ? HeKEY(entry) : ""),
963 hv_iterval(HV *hv, register HE *entry)
965 if (SvRMAGICAL(hv)) {
966 if (mg_find((SV*)hv,'P')) {
967 SV* sv = sv_newmortal();
968 if (HeKLEN(entry) == HEf_SVKEY)
969 mg_copy((SV*)hv, sv, (char*)HeKEY_sv(entry), HEf_SVKEY);
970 else mg_copy((SV*)hv, sv, HeKEY(entry), HeKLEN(entry));
978 hv_iternextsv(HV *hv, char **key, I32 *retlen)
981 if ( (he = hv_iternext(hv)) == NULL)
983 *key = hv_iterkey(he, retlen);
984 return hv_iterval(hv, he);
988 hv_magic(HV *hv, GV *gv, int how)
990 sv_magic((SV*)hv, (SV*)gv, how, Nullch, 0);
994 sharepvn(char *sv, I32 len, U32 hash)
996 return HEK_KEY(share_hek(sv, len, hash));
999 /* possibly free a shared string if no one has access to it
1000 * len and hash must both be valid for str.
1003 unsharepvn(char *str, I32 len, U32 hash)
1005 register XPVHV* xhv;
1007 register HE **oentry;
1011 /* what follows is the moral equivalent of:
1012 if ((Svp = hv_fetch(strtab, tmpsv, FALSE, hash))) {
1013 if (--*Svp == Nullsv)
1014 hv_delete(strtab, str, len, G_DISCARD, hash);
1016 xhv = (XPVHV*)SvANY(strtab);
1017 /* assert(xhv_array != 0) */
1018 oentry = &((HE**)xhv->xhv_array)[hash & (I32) xhv->xhv_max];
1019 for (entry = *oentry; entry; i=0, oentry = &HeNEXT(entry), entry = *oentry) {
1020 if (HeHASH(entry) != hash) /* strings can't be equal */
1022 if (HeKLEN(entry) != len)
1024 if (memNE(HeKEY(entry),str,len)) /* is this it? */
1027 if (--HeVAL(entry) == Nullsv) {
1028 *oentry = HeNEXT(entry);
1031 Safefree(HeKEY_hek(entry));
1039 warn("Attempt to free non-existent shared string");
1042 /* get a (constant) string ptr from the global string table
1043 * string will get added if it is not already there.
1044 * len and hash must both be valid for str.
1047 share_hek(char *str, I32 len, register U32 hash)
1049 register XPVHV* xhv;
1051 register HE **oentry;
1055 /* what follows is the moral equivalent of:
1057 if (!(Svp = hv_fetch(strtab, str, len, FALSE)))
1058 hv_store(strtab, str, len, Nullsv, hash);
1060 xhv = (XPVHV*)SvANY(strtab);
1061 /* assert(xhv_array != 0) */
1062 oentry = &((HE**)xhv->xhv_array)[hash & (I32) xhv->xhv_max];
1063 for (entry = *oentry; entry; i=0, entry = HeNEXT(entry)) {
1064 if (HeHASH(entry) != hash) /* strings can't be equal */
1066 if (HeKLEN(entry) != len)
1068 if (memNE(HeKEY(entry),str,len)) /* is this it? */
1075 HeKEY_hek(entry) = save_hek(str, len, hash);
1076 HeVAL(entry) = Nullsv;
1077 HeNEXT(entry) = *oentry;
1080 if (i) { /* initial entry? */
1082 if (xhv->xhv_keys > xhv->xhv_max)
1087 ++HeVAL(entry); /* use value slot as REFCNT */
1088 return HeKEY_hek(entry);