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));
19 static void hv_magic_check _((HV *hv, bool *needs_copy, bool *needs_store));
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 *hv, bool *needs_copy, bool *needs_store)
222 MAGIC *mg = SvMAGIC(hv);
226 if (isUPPER(mg->mg_type)) {
228 switch (mg->mg_type) {
232 *needs_store = FALSE;
235 mg = mg->mg_moremagic;
240 hv_store(HV *hv, char *key, U32 klen, SV *val, register U32 hash)
245 register HE **oentry;
250 xhv = (XPVHV*)SvANY(hv);
254 hv_magic_check (hv, &needs_copy, &needs_store);
256 mg_copy((SV*)hv, val, key, klen);
257 if (!xhv->xhv_array && !needs_store)
262 PERL_HASH(hash, key, klen);
265 Newz(505, xhv->xhv_array, sizeof(HE**) * (xhv->xhv_max + 1), char);
267 oentry = &((HE**)xhv->xhv_array)[hash & (I32) xhv->xhv_max];
270 for (entry = *oentry; entry; i=0, entry = HeNEXT(entry)) {
271 if (HeHASH(entry) != hash) /* strings can't be equal */
273 if (HeKLEN(entry) != klen)
275 if (memNE(HeKEY(entry),key,klen)) /* is this it? */
277 SvREFCNT_dec(HeVAL(entry));
279 return &HeVAL(entry);
284 HeKEY_hek(entry) = share_hek(key, klen, hash);
285 else /* gotta do the real thing */
286 HeKEY_hek(entry) = save_hek(key, klen, hash);
288 HeNEXT(entry) = *oentry;
292 if (i) { /* initial entry? */
294 if (xhv->xhv_keys > xhv->xhv_max)
298 return &HeVAL(entry);
302 hv_store_ent(HV *hv, SV *keysv, SV *val, register U32 hash)
309 register HE **oentry;
314 xhv = (XPVHV*)SvANY(hv);
319 hv_magic_check (hv, &needs_copy, &needs_store);
321 bool save_taint = tainted;
323 tainted = SvTAINTED(keysv);
324 keysv = sv_2mortal(newSVsv(keysv));
325 mg_copy((SV*)hv, val, (char*)keysv, HEf_SVKEY);
326 TAINT_IF(save_taint);
327 if (!xhv->xhv_array && !needs_store)
332 key = SvPV(keysv, klen);
335 PERL_HASH(hash, key, klen);
338 Newz(505, xhv->xhv_array, sizeof(HE**) * (xhv->xhv_max + 1), char);
340 oentry = &((HE**)xhv->xhv_array)[hash & (I32) xhv->xhv_max];
343 for (entry = *oentry; entry; i=0, entry = HeNEXT(entry)) {
344 if (HeHASH(entry) != hash) /* strings can't be equal */
346 if (HeKLEN(entry) != klen)
348 if (memNE(HeKEY(entry),key,klen)) /* is this it? */
350 SvREFCNT_dec(HeVAL(entry));
357 HeKEY_hek(entry) = share_hek(key, klen, hash);
358 else /* gotta do the real thing */
359 HeKEY_hek(entry) = save_hek(key, klen, hash);
361 HeNEXT(entry) = *oentry;
365 if (i) { /* initial entry? */
367 if (xhv->xhv_keys > xhv->xhv_max)
375 hv_delete(HV *hv, char *key, U32 klen, I32 flags)
381 register HE **oentry;
386 if (SvRMAGICAL(hv)) {
387 sv = *hv_fetch(hv, key, klen, TRUE);
389 if (mg_find(sv, 's')) {
390 return Nullsv; /* %SIG elements cannot be deleted */
392 if (mg_find(sv, 'p')) {
393 sv_unmagic(sv, 'p'); /* No longer an element */
397 xhv = (XPVHV*)SvANY(hv);
401 PERL_HASH(hash, key, klen);
403 oentry = &((HE**)xhv->xhv_array)[hash & (I32) xhv->xhv_max];
406 for (; entry; i=0, oentry = &HeNEXT(entry), entry = *oentry) {
407 if (HeHASH(entry) != hash) /* strings can't be equal */
409 if (HeKLEN(entry) != klen)
411 if (memNE(HeKEY(entry),key,klen)) /* is this it? */
413 *oentry = HeNEXT(entry);
416 if (flags & G_DISCARD)
419 sv = sv_mortalcopy(HeVAL(entry));
420 if (entry == xhv->xhv_eiter)
423 hv_free_ent(hv, entry);
431 hv_delete_ent(HV *hv, SV *keysv, I32 flags, U32 hash)
438 register HE **oentry;
443 if (SvRMAGICAL(hv)) {
444 entry = hv_fetch_ent(hv, keysv, TRUE, hash);
447 if (mg_find(sv, 'p')) {
448 sv_unmagic(sv, 'p'); /* No longer an element */
452 xhv = (XPVHV*)SvANY(hv);
456 key = SvPV(keysv, klen);
459 PERL_HASH(hash, key, klen);
461 oentry = &((HE**)xhv->xhv_array)[hash & (I32) xhv->xhv_max];
464 for (; entry; i=0, oentry = &HeNEXT(entry), entry = *oentry) {
465 if (HeHASH(entry) != hash) /* strings can't be equal */
467 if (HeKLEN(entry) != klen)
469 if (memNE(HeKEY(entry),key,klen)) /* is this it? */
471 *oentry = HeNEXT(entry);
474 if (flags & G_DISCARD)
477 sv = sv_mortalcopy(HeVAL(entry));
478 if (entry == xhv->xhv_eiter)
481 hv_free_ent(hv, entry);
489 hv_exists(HV *hv, char *key, U32 klen)
499 if (SvRMAGICAL(hv)) {
500 if (mg_find((SV*)hv,'P')) {
503 mg_copy((SV*)hv, sv, key, klen);
504 magic_existspack(sv, mg_find(sv, 'p'));
509 xhv = (XPVHV*)SvANY(hv);
513 PERL_HASH(hash, key, klen);
515 entry = ((HE**)xhv->xhv_array)[hash & (I32) xhv->xhv_max];
516 for (; entry; entry = HeNEXT(entry)) {
517 if (HeHASH(entry) != hash) /* strings can't be equal */
519 if (HeKLEN(entry) != klen)
521 if (memNE(HeKEY(entry),key,klen)) /* is this it? */
530 hv_exists_ent(HV *hv, SV *keysv, U32 hash)
541 if (SvRMAGICAL(hv)) {
542 if (mg_find((SV*)hv,'P')) {
543 dTHR; /* just for SvTRUE */
545 keysv = sv_2mortal(newSVsv(keysv));
546 mg_copy((SV*)hv, sv, (char*)keysv, HEf_SVKEY);
547 magic_existspack(sv, mg_find(sv, 'p'));
552 xhv = (XPVHV*)SvANY(hv);
556 key = SvPV(keysv, klen);
558 PERL_HASH(hash, key, klen);
560 entry = ((HE**)xhv->xhv_array)[hash & (I32) xhv->xhv_max];
561 for (; entry; entry = HeNEXT(entry)) {
562 if (HeHASH(entry) != hash) /* strings can't be equal */
564 if (HeKLEN(entry) != klen)
566 if (memNE(HeKEY(entry),key,klen)) /* is this it? */
576 register XPVHV* xhv = (XPVHV*)SvANY(hv);
577 I32 oldsize = (I32) xhv->xhv_max + 1; /* sic(k) */
578 register I32 newsize = oldsize * 2;
583 register HE **oentry;
584 #ifndef STRANGE_MALLOC
588 a = (HE**)xhv->xhv_array;
590 #ifdef STRANGE_MALLOC
591 Renew(a, newsize, HE*);
593 i = newsize * sizeof(HE*);
594 #define MALLOC_OVERHEAD 16
595 tmp = MALLOC_OVERHEAD;
596 while (tmp - MALLOC_OVERHEAD < i)
598 tmp -= MALLOC_OVERHEAD;
600 assert(tmp >= newsize);
602 Copy(xhv->xhv_array, a, oldsize, HE*);
604 offer_nice_chunk(xhv->xhv_array,
605 oldsize * sizeof(HE*) * 2 - MALLOC_OVERHEAD);
608 Safefree(xhv->xhv_array);
612 Zero(&a[oldsize], oldsize, HE*); /* zero 2nd half*/
613 xhv->xhv_max = --newsize;
614 xhv->xhv_array = (char*)a;
616 for (i=0; i<oldsize; i++,a++) {
617 if (!*a) /* non-existent */
620 for (oentry = a, entry = *a; entry; entry = *oentry) {
621 if ((HeHASH(entry) & newsize) != i) {
622 *oentry = HeNEXT(entry);
630 oentry = &HeNEXT(entry);
632 if (!*a) /* everything moved */
638 hv_ksplit(HV *hv, IV newmax)
640 register XPVHV* xhv = (XPVHV*)SvANY(hv);
641 I32 oldsize = (I32) xhv->xhv_max + 1; /* sic(k) */
642 register I32 newsize;
647 register HE **oentry;
649 newsize = (I32) newmax; /* possible truncation here */
650 if (newsize != newmax || newmax <= oldsize)
652 while ((newsize & (1 + ~newsize)) != newsize) {
653 newsize &= ~(newsize & (1 + ~newsize)); /* get proper power of 2 */
655 if (newsize < newmax)
657 if (newsize < newmax)
658 return; /* overflow detection */
660 a = (HE**)xhv->xhv_array;
663 #ifdef STRANGE_MALLOC
664 Renew(a, newsize, HE*);
666 i = newsize * sizeof(HE*);
668 while (j - MALLOC_OVERHEAD < i)
670 j -= MALLOC_OVERHEAD;
672 assert(j >= newsize);
674 Copy(xhv->xhv_array, a, oldsize, HE*);
676 offer_nice_chunk(xhv->xhv_array,
677 oldsize * sizeof(HE*) * 2 - MALLOC_OVERHEAD);
680 Safefree(xhv->xhv_array);
683 Zero(&a[oldsize], newsize-oldsize, HE*); /* zero 2nd half*/
686 Newz(0, a, newsize, HE*);
688 xhv->xhv_max = --newsize;
689 xhv->xhv_array = (char*)a;
690 if (!xhv->xhv_fill) /* skip rest if no entries */
693 for (i=0; i<oldsize; i++,a++) {
694 if (!*a) /* non-existent */
696 for (oentry = a, entry = *a; entry; entry = *oentry) {
697 if ((j = (HeHASH(entry) & newsize)) != i) {
699 *oentry = HeNEXT(entry);
700 if (!(HeNEXT(entry) = a[j]))
706 oentry = &HeNEXT(entry);
708 if (!*a) /* everything moved */
719 hv = (HV*)NEWSV(502,0);
720 sv_upgrade((SV *)hv, SVt_PVHV);
721 xhv = (XPVHV*)SvANY(hv);
724 #ifndef NODEFAULT_SHAREKEYS
725 HvSHAREKEYS_on(hv); /* key-sharing on by default */
727 xhv->xhv_max = 7; /* start with 8 buckets */
730 (void)hv_iterinit(hv); /* so each() will start off right */
735 hv_free_ent(HV *hv, register HE *entry)
739 if (isGV(HeVAL(entry)) && GvCVu(HeVAL(entry)) && HvNAME(hv))
740 sub_generation++; /* may be deletion of method from stash */
741 SvREFCNT_dec(HeVAL(entry));
742 if (HeKLEN(entry) == HEf_SVKEY) {
743 SvREFCNT_dec(HeKEY_sv(entry));
744 Safefree(HeKEY_hek(entry));
746 else if (HvSHAREKEYS(hv))
747 unshare_hek(HeKEY_hek(entry));
749 Safefree(HeKEY_hek(entry));
754 hv_delayfree_ent(HV *hv, register HE *entry)
758 if (isGV(HeVAL(entry)) && GvCVu(HeVAL(entry)) && HvNAME(hv))
759 sub_generation++; /* may be deletion of method from stash */
760 sv_2mortal(HeVAL(entry)); /* free between statements */
761 if (HeKLEN(entry) == HEf_SVKEY) {
762 sv_2mortal(HeKEY_sv(entry));
763 Safefree(HeKEY_hek(entry));
765 else if (HvSHAREKEYS(hv))
766 unshare_hek(HeKEY_hek(entry));
768 Safefree(HeKEY_hek(entry));
778 xhv = (XPVHV*)SvANY(hv);
783 (void)memzero(xhv->xhv_array, (xhv->xhv_max + 1) * sizeof(HE*));
794 register HE *oentry = Null(HE*);
810 entry = HeNEXT(entry);
811 hv_free_ent(hv, oentry);
816 entry = array[riter];
819 (void)hv_iterinit(hv);
828 xhv = (XPVHV*)SvANY(hv);
830 Safefree(xhv->xhv_array);
832 Safefree(HvNAME(hv));
836 xhv->xhv_max = 7; /* it's a normal hash */
852 xhv = (XPVHV*)SvANY(hv);
853 entry = xhv->xhv_eiter;
854 #ifdef DYNAMIC_ENV_FETCH /* set up %ENV for iteration */
855 if (HvNAME(hv) && strEQ(HvNAME(hv), ENV_HV_NAME))
858 if (entry && HvLAZYDEL(hv)) { /* was deleted earlier? */
860 hv_free_ent(hv, entry);
863 xhv->xhv_eiter = Null(HE*);
864 return xhv->xhv_fill; /* should be xhv->xhv_keys? May change later */
877 xhv = (XPVHV*)SvANY(hv);
878 oldentry = entry = xhv->xhv_eiter;
880 if (SvRMAGICAL(hv) && (mg = mg_find((SV*)hv,'P'))) {
881 SV *key = sv_newmortal();
883 sv_setsv(key, HeSVKEY_force(entry));
884 SvREFCNT_dec(HeSVKEY(entry)); /* get rid of previous key */
890 xhv->xhv_eiter = entry = new_he(); /* one HE per MAGICAL hash */
892 Newz(54, k, HEK_BASESIZE + sizeof(SV*), char);
894 HeKEY_hek(entry) = hek;
895 HeKLEN(entry) = HEf_SVKEY;
897 magic_nextpack((SV*) hv,mg,key);
899 /* force key to stay around until next time */
900 HeSVKEY_set(entry, SvREFCNT_inc(key));
901 return entry; /* beware, hent_val is not set */
904 SvREFCNT_dec(HeVAL(entry));
905 Safefree(HeKEY_hek(entry));
907 xhv->xhv_eiter = Null(HE*);
912 Newz(506,xhv->xhv_array, sizeof(HE*) * (xhv->xhv_max + 1), char);
914 entry = HeNEXT(entry);
917 if (xhv->xhv_riter > xhv->xhv_max) {
921 entry = ((HE**)xhv->xhv_array)[xhv->xhv_riter];
924 if (oldentry && HvLAZYDEL(hv)) { /* was deleted earlier? */
926 hv_free_ent(hv, oldentry);
929 xhv->xhv_eiter = entry;
934 hv_iterkey(register HE *entry, I32 *retlen)
936 if (HeKLEN(entry) == HEf_SVKEY) {
938 char *p = SvPV(HeKEY_sv(entry), len);
943 *retlen = HeKLEN(entry);
948 /* unlike hv_iterval(), this always returns a mortal copy of the key */
950 hv_iterkeysv(register HE *entry)
952 if (HeKLEN(entry) == HEf_SVKEY)
953 return sv_mortalcopy(HeKEY_sv(entry));
955 return sv_2mortal(newSVpv((HeKLEN(entry) ? HeKEY(entry) : ""),
960 hv_iterval(HV *hv, register HE *entry)
962 if (SvRMAGICAL(hv)) {
963 if (mg_find((SV*)hv,'P')) {
964 SV* sv = sv_newmortal();
965 if (HeKLEN(entry) == HEf_SVKEY)
966 mg_copy((SV*)hv, sv, (char*)HeKEY_sv(entry), HEf_SVKEY);
967 else mg_copy((SV*)hv, sv, HeKEY(entry), HeKLEN(entry));
975 hv_iternextsv(HV *hv, char **key, I32 *retlen)
978 if ( (he = hv_iternext(hv)) == NULL)
980 *key = hv_iterkey(he, retlen);
981 return hv_iterval(hv, he);
985 hv_magic(HV *hv, GV *gv, int how)
987 sv_magic((SV*)hv, (SV*)gv, how, Nullch, 0);
991 sharepvn(char *sv, I32 len, U32 hash)
993 return HEK_KEY(share_hek(sv, len, hash));
996 /* possibly free a shared string if no one has access to it
997 * len and hash must both be valid for str.
1000 unsharepvn(char *str, I32 len, U32 hash)
1002 register XPVHV* xhv;
1004 register HE **oentry;
1008 /* what follows is the moral equivalent of:
1009 if ((Svp = hv_fetch(strtab, tmpsv, FALSE, hash))) {
1010 if (--*Svp == Nullsv)
1011 hv_delete(strtab, str, len, G_DISCARD, hash);
1013 xhv = (XPVHV*)SvANY(strtab);
1014 /* assert(xhv_array != 0) */
1015 oentry = &((HE**)xhv->xhv_array)[hash & (I32) xhv->xhv_max];
1016 for (entry = *oentry; entry; i=0, oentry = &HeNEXT(entry), entry = *oentry) {
1017 if (HeHASH(entry) != hash) /* strings can't be equal */
1019 if (HeKLEN(entry) != len)
1021 if (memNE(HeKEY(entry),str,len)) /* is this it? */
1024 if (--HeVAL(entry) == Nullsv) {
1025 *oentry = HeNEXT(entry);
1028 Safefree(HeKEY_hek(entry));
1036 warn("Attempt to free non-existent shared string");
1039 /* get a (constant) string ptr from the global string table
1040 * string will get added if it is not already there.
1041 * len and hash must both be valid for str.
1044 share_hek(char *str, I32 len, register U32 hash)
1046 register XPVHV* xhv;
1048 register HE **oentry;
1052 /* what follows is the moral equivalent of:
1054 if (!(Svp = hv_fetch(strtab, str, len, FALSE)))
1055 hv_store(strtab, str, len, Nullsv, hash);
1057 xhv = (XPVHV*)SvANY(strtab);
1058 /* assert(xhv_array != 0) */
1059 oentry = &((HE**)xhv->xhv_array)[hash & (I32) xhv->xhv_max];
1060 for (entry = *oentry; entry; i=0, entry = HeNEXT(entry)) {
1061 if (HeHASH(entry) != hash) /* strings can't be equal */
1063 if (HeKLEN(entry) != len)
1065 if (memNE(HeKEY(entry),str,len)) /* is this it? */
1072 HeKEY_hek(entry) = save_hek(str, len, hash);
1073 HeVAL(entry) = Nullsv;
1074 HeNEXT(entry) = *oentry;
1077 if (i) { /* initial entry? */
1079 if (xhv->xhv_keys > xhv->xhv_max)
1084 ++HeVAL(entry); /* use value slot as REFCNT */
1085 return HeKEY_hek(entry);