3 * Copyright (C) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
4 * 2000, 2001, 2002, 2003, 2004, 2005 by Larry Wall and others
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.
12 * "...for the Entwives desired order, and plenty, and peace (by which they
13 * meant that things should remain where they had set them)." --Treebeard
17 =head1 Array Manipulation Functions
25 Perl_av_reify(pTHX_ AV *av)
32 if (SvTIED_mg((SV*)av, PERL_MAGIC_tied) && ckWARN_d(WARN_DEBUGGING))
33 Perl_warner(aTHX_ packWARN(WARN_DEBUGGING), "av_reify called on tied array");
36 while (key > AvFILLp(av) + 1)
37 AvARRAY(av)[--key] = &PL_sv_undef;
39 SV * const sv = AvARRAY(av)[--key];
41 if (sv != &PL_sv_undef)
42 (void)SvREFCNT_inc(sv);
44 key = AvARRAY(av) - AvALLOC(av);
46 AvALLOC(av)[--key] = &PL_sv_undef;
54 Pre-extend an array. The C<key> is the index to which the array should be
61 Perl_av_extend(pTHX_ AV *av, I32 key)
64 if ((mg = SvTIED_mg((SV*)av, PERL_MAGIC_tied))) {
68 PUSHSTACKi(PERLSI_MAGIC);
71 PUSHs(SvTIED_obj((SV*)av, mg));
72 PUSHs(sv_2mortal(newSViv(key+1)));
74 call_method("EXTEND", G_SCALAR|G_DISCARD);
80 if (key > AvMAX(av)) {
85 if (AvALLOC(av) != AvARRAY(av)) {
86 ary = AvALLOC(av) + AvFILLp(av) + 1;
87 tmp = AvARRAY(av) - AvALLOC(av);
88 Move(AvARRAY(av), AvALLOC(av), AvFILLp(av)+1, SV*);
90 SvPV_set(av, (char*)AvALLOC(av));
93 ary[--tmp] = &PL_sv_undef;
96 if (key > AvMAX(av) - 10) {
97 newmax = key + AvMAX(av);
102 #ifdef PERL_MALLOC_WRAP
103 static const char oom_array_extend[] =
104 "Out of memory during array extend"; /* Duplicated in pp_hot.c */
108 #if !defined(STRANGE_MALLOC) && !defined(MYMALLOC)
114 newmax = malloced_size((void*)AvALLOC(av))/sizeof(SV*) - 1;
119 newmax = key + AvMAX(av) / 5;
121 MEM_WRAP_CHECK_1(newmax+1, SV*, oom_array_extend);
122 #if defined(STRANGE_MALLOC) || defined(MYMALLOC)
123 Renew(AvALLOC(av),newmax+1, SV*);
125 bytes = (newmax + 1) * sizeof(SV*);
126 #define MALLOC_OVERHEAD 16
127 itmp = MALLOC_OVERHEAD;
128 while ((MEM_SIZE)(itmp - MALLOC_OVERHEAD) < bytes)
130 itmp -= MALLOC_OVERHEAD;
132 assert(itmp > newmax);
134 assert(newmax >= AvMAX(av));
135 New(2,ary, newmax+1, SV*);
136 Copy(AvALLOC(av), ary, AvMAX(av)+1, SV*);
138 offer_nice_chunk(AvALLOC(av), (AvMAX(av)+1) * sizeof(SV*));
140 Safefree(AvALLOC(av));
146 ary = AvALLOC(av) + AvMAX(av) + 1;
147 tmp = newmax - AvMAX(av);
148 if (av == PL_curstack) { /* Oops, grew stack (via av_store()?) */
149 PL_stack_sp = AvALLOC(av) + (PL_stack_sp - PL_stack_base);
150 PL_stack_base = AvALLOC(av);
151 PL_stack_max = PL_stack_base + newmax;
155 newmax = key < 3 ? 3 : key;
156 MEM_WRAP_CHECK_1(newmax+1, SV*, oom_array_extend);
157 New(2,AvALLOC(av), newmax+1, SV*);
158 ary = AvALLOC(av) + 1;
160 AvALLOC(av)[0] = &PL_sv_undef; /* For the stacks */
164 ary[--tmp] = &PL_sv_undef;
167 SvPV_set(av, (char*)AvALLOC(av));
176 Returns the SV at the specified index in the array. The C<key> is the
177 index. If C<lval> is set then the fetch will be part of a store. Check
178 that the return value is non-null before dereferencing it to a C<SV*>.
180 See L<perlguts/"Understanding the Magic of Tied Hashes and Arrays"> for
181 more information on how to use this function on tied arrays.
187 Perl_av_fetch(pTHX_ register AV *av, I32 key, I32 lval)
194 if (SvRMAGICAL(av)) {
195 const MAGIC * const tied_magic = mg_find((SV*)av, PERL_MAGIC_tied);
196 if (tied_magic || mg_find((SV*)av, PERL_MAGIC_regdata)) {
197 U32 adjust_index = 1;
199 if (tied_magic && key < 0) {
200 /* Handle negative array indices 20020222 MJD */
201 SV **negative_indices_glob =
202 hv_fetch(SvSTASH(SvRV(SvTIED_obj((SV *)av,
204 NEGATIVE_INDICES_VAR, 16, 0);
206 if (negative_indices_glob
207 && SvTRUE(GvSV(*negative_indices_glob)))
211 if (key < 0 && adjust_index) {
212 key += AvFILL(av) + 1;
218 sv_upgrade(sv, SVt_PVLV);
219 mg_copy((SV*)av, sv, 0, key);
221 LvTARG(sv) = sv; /* fake (SV**) */
222 return &(LvTARG(sv));
227 key += AvFILL(av) + 1;
232 if (key > AvFILLp(av)) {
236 return av_store(av,key,sv);
238 if (AvARRAY(av)[key] == &PL_sv_undef) {
242 return av_store(av,key,sv);
247 && (!AvARRAY(av)[key] /* eg. @_ could have freed elts */
248 || SvTYPE(AvARRAY(av)[key]) == SVTYPEMASK)) {
249 AvARRAY(av)[key] = &PL_sv_undef; /* 1/2 reify */
252 return &AvARRAY(av)[key];
258 Stores an SV in an array. The array index is specified as C<key>. The
259 return value will be NULL if the operation failed or if the value did not
260 need to be actually stored within the array (as in the case of tied
261 arrays). Otherwise it can be dereferenced to get the original C<SV*>. Note
262 that the caller is responsible for suitably incrementing the reference
263 count of C<val> before the call, and decrementing it if the function
266 See L<perlguts/"Understanding the Magic of Tied Hashes and Arrays"> for
267 more information on how to use this function on tied arrays.
273 Perl_av_store(pTHX_ register AV *av, I32 key, SV *val)
282 if (SvRMAGICAL(av)) {
283 const MAGIC * const tied_magic = mg_find((SV*)av, PERL_MAGIC_tied);
285 /* Handle negative array indices 20020222 MJD */
287 unsigned adjust_index = 1;
288 SV **negative_indices_glob =
289 hv_fetch(SvSTASH(SvRV(SvTIED_obj((SV *)av,
291 NEGATIVE_INDICES_VAR, 16, 0);
292 if (negative_indices_glob
293 && SvTRUE(GvSV(*negative_indices_glob)))
296 key += AvFILL(av) + 1;
301 if (val != &PL_sv_undef) {
302 mg_copy((SV*)av, val, 0, key);
310 key += AvFILL(av) + 1;
315 if (SvREADONLY(av) && key >= AvFILL(av))
316 Perl_croak(aTHX_ PL_no_modify);
318 if (!AvREAL(av) && AvREIFY(av))
323 if (AvFILLp(av) < key) {
325 if (av == PL_curstack && key > PL_stack_sp - PL_stack_base)
326 PL_stack_sp = PL_stack_base + key; /* XPUSH in disguise */
328 ary[++AvFILLp(av)] = &PL_sv_undef;
329 while (AvFILLp(av) < key);
334 SvREFCNT_dec(ary[key]);
336 if (SvSMAGICAL(av)) {
337 if (val != &PL_sv_undef) {
338 MAGIC* mg = SvMAGIC(av);
339 sv_magic(val, (SV*)av, toLOWER(mg->mg_type), 0, key);
349 Creates a new AV. The reference count is set to 1.
359 av = (AV*)NEWSV(3,0);
360 sv_upgrade((SV *)av, SVt_PVAV);
363 SvPV_set(av, (char*)0);
364 AvMAX(av) = AvFILLp(av) = -1;
371 Creates a new AV and populates it with a list of SVs. The SVs are copied
372 into the array, so they may be freed after the call to av_make. The new AV
373 will have a reference count of 1.
379 Perl_av_make(pTHX_ register I32 size, register SV **strp)
383 av = (AV*)NEWSV(8,0);
384 sv_upgrade((SV *) av,SVt_PVAV);
386 if (size) { /* `defined' was returning undef for size==0 anyway. */
391 SvPV_set(av, (char*)ary);
392 AvFILLp(av) = size - 1;
393 AvMAX(av) = size - 1;
394 for (i = 0; i < size; i++) {
397 sv_setsv(ary[i], *strp);
405 Perl_av_fake(pTHX_ register I32 size, register SV **strp)
410 av = (AV*)NEWSV(9,0);
411 sv_upgrade((SV *)av, SVt_PVAV);
412 New(4,ary,size+1,SV*);
414 Copy(strp,ary,size,SV*);
416 SvPV_set(av, (char*)ary);
417 AvFILLp(av) = size - 1;
418 AvMAX(av) = size - 1;
430 Clears an array, making it empty. Does not free the memory used by the
437 Perl_av_clear(pTHX_ register AV *av)
442 if (SvREFCNT(av) == 0 && ckWARN_d(WARN_DEBUGGING)) {
443 Perl_warner(aTHX_ packWARN(WARN_DEBUGGING), "Attempt to clear deleted array");
451 Perl_croak(aTHX_ PL_no_modify);
453 /* Give any tie a chance to cleanup first */
461 SV** ary = AvARRAY(av);
462 key = AvFILLp(av) + 1;
464 SV * sv = ary[--key];
465 /* undef the slot before freeing the value, because a
466 * destructor might try to modify this arrray */
467 ary[key] = &PL_sv_undef;
471 if ((key = AvARRAY(av) - AvALLOC(av))) {
473 SvPV_set(av, (char*)AvALLOC(av));
482 Undefines the array. Frees the memory used by the array itself.
488 Perl_av_undef(pTHX_ register AV *av)
494 /* Give any tie a chance to cleanup first */
495 if (SvTIED_mg((SV*)av, PERL_MAGIC_tied))
496 av_fill(av, -1); /* mg_clear() ? */
499 register I32 key = AvFILLp(av) + 1;
501 SvREFCNT_dec(AvARRAY(av)[--key]);
503 Safefree(AvALLOC(av));
505 SvPV_set(av, (char*)0);
506 AvMAX(av) = AvFILLp(av) = -1;
508 SvREFCNT_dec(AvARYLEN(av));
516 Pushes an SV onto the end of the array. The array will grow automatically
517 to accommodate the addition.
523 Perl_av_push(pTHX_ register AV *av, SV *val)
530 Perl_croak(aTHX_ PL_no_modify);
532 if ((mg = SvTIED_mg((SV*)av, PERL_MAGIC_tied))) {
534 PUSHSTACKi(PERLSI_MAGIC);
537 PUSHs(SvTIED_obj((SV*)av, mg));
541 call_method("PUSH", G_SCALAR|G_DISCARD);
546 av_store(av,AvFILLp(av)+1,val);
552 Pops an SV off the end of the array. Returns C<&PL_sv_undef> if the array
559 Perl_av_pop(pTHX_ register AV *av)
568 Perl_croak(aTHX_ PL_no_modify);
569 if ((mg = SvTIED_mg((SV*)av, PERL_MAGIC_tied))) {
571 PUSHSTACKi(PERLSI_MAGIC);
573 XPUSHs(SvTIED_obj((SV*)av, mg));
576 if (call_method("POP", G_SCALAR)) {
577 retval = newSVsv(*PL_stack_sp--);
579 retval = &PL_sv_undef;
587 retval = AvARRAY(av)[AvFILLp(av)];
588 AvARRAY(av)[AvFILLp(av)--] = &PL_sv_undef;
595 =for apidoc av_unshift
597 Unshift the given number of C<undef> values onto the beginning of the
598 array. The array will grow automatically to accommodate the addition. You
599 must then use C<av_store> to assign values to these new elements.
605 Perl_av_unshift(pTHX_ register AV *av, register I32 num)
614 Perl_croak(aTHX_ PL_no_modify);
616 if ((mg = SvTIED_mg((SV*)av, PERL_MAGIC_tied))) {
618 PUSHSTACKi(PERLSI_MAGIC);
621 PUSHs(SvTIED_obj((SV*)av, mg));
627 call_method("UNSHIFT", G_SCALAR|G_DISCARD);
635 if (!AvREAL(av) && AvREIFY(av))
637 i = AvARRAY(av) - AvALLOC(av);
645 SvPV_set(av, (char*)(AvARRAY(av) - i));
651 /* Create extra elements */
652 slide = i > 0 ? i : 0;
654 av_extend(av, i + num);
657 Move(ary, ary + num, i + 1, SV*);
659 ary[--num] = &PL_sv_undef;
661 /* Make extra elements into a buffer */
663 AvFILLp(av) -= slide;
664 SvPV_set(av, (char*)(AvARRAY(av) + slide));
671 Shifts an SV off the beginning of the array.
677 Perl_av_shift(pTHX_ register AV *av)
686 Perl_croak(aTHX_ PL_no_modify);
687 if ((mg = SvTIED_mg((SV*)av, PERL_MAGIC_tied))) {
689 PUSHSTACKi(PERLSI_MAGIC);
691 XPUSHs(SvTIED_obj((SV*)av, mg));
694 if (call_method("SHIFT", G_SCALAR)) {
695 retval = newSVsv(*PL_stack_sp--);
697 retval = &PL_sv_undef;
705 retval = *AvARRAY(av);
707 *AvARRAY(av) = &PL_sv_undef;
708 SvPV_set(av, (char*)(AvARRAY(av) + 1));
719 Returns the highest index in the array. Returns -1 if the array is
726 Perl_av_len(pTHX_ const register AV *av)
734 Ensure than an array has a given number of elements, equivalent to
735 Perl's C<$#array = $fill;>.
740 Perl_av_fill(pTHX_ register AV *av, I32 fill)
745 Perl_croak(aTHX_ "panic: null array");
748 if ((mg = SvTIED_mg((SV*)av, PERL_MAGIC_tied))) {
752 PUSHSTACKi(PERLSI_MAGIC);
755 PUSHs(SvTIED_obj((SV*)av, mg));
756 PUSHs(sv_2mortal(newSViv(fill+1)));
758 call_method("STORESIZE", G_SCALAR|G_DISCARD);
764 if (fill <= AvMAX(av)) {
765 I32 key = AvFILLp(av);
766 SV** ary = AvARRAY(av);
770 SvREFCNT_dec(ary[key]);
771 ary[key--] = &PL_sv_undef;
776 ary[++key] = &PL_sv_undef;
784 (void)av_store(av,fill,&PL_sv_undef);
788 =for apidoc av_delete
790 Deletes the element indexed by C<key> from the array. Returns the
791 deleted element. If C<flags> equals C<G_DISCARD>, the element is freed
792 and null is returned.
797 Perl_av_delete(pTHX_ AV *av, I32 key, I32 flags)
804 Perl_croak(aTHX_ PL_no_modify);
806 if (SvRMAGICAL(av)) {
807 const MAGIC * const tied_magic = mg_find((SV*)av, PERL_MAGIC_tied);
808 if ((tied_magic || mg_find((SV*)av, PERL_MAGIC_regdata))) {
809 /* Handle negative array indices 20020222 MJD */
812 unsigned adjust_index = 1;
814 SV **negative_indices_glob =
815 hv_fetch(SvSTASH(SvRV(SvTIED_obj((SV *)av,
817 NEGATIVE_INDICES_VAR, 16, 0);
818 if (negative_indices_glob
819 && SvTRUE(GvSV(*negative_indices_glob)))
823 key += AvFILL(av) + 1;
828 svp = av_fetch(av, key, TRUE);
832 if (mg_find(sv, PERL_MAGIC_tiedelem)) {
833 sv_unmagic(sv, PERL_MAGIC_tiedelem); /* No longer an element */
842 key += AvFILL(av) + 1;
847 if (key > AvFILLp(av))
850 if (!AvREAL(av) && AvREIFY(av))
852 sv = AvARRAY(av)[key];
853 if (key == AvFILLp(av)) {
854 AvARRAY(av)[key] = &PL_sv_undef;
857 } while (--key >= 0 && AvARRAY(av)[key] == &PL_sv_undef);
860 AvARRAY(av)[key] = &PL_sv_undef;
864 if (flags & G_DISCARD) {
874 =for apidoc av_exists
876 Returns true if the element indexed by C<key> has been initialized.
878 This relies on the fact that uninitialized array elements are set to
884 Perl_av_exists(pTHX_ AV *av, I32 key)
890 if (SvRMAGICAL(av)) {
891 const MAGIC * const tied_magic = mg_find((SV*)av, PERL_MAGIC_tied);
892 if (tied_magic || mg_find((SV*)av, PERL_MAGIC_regdata)) {
893 SV *sv = sv_newmortal();
895 /* Handle negative array indices 20020222 MJD */
897 unsigned adjust_index = 1;
899 SV **negative_indices_glob =
900 hv_fetch(SvSTASH(SvRV(SvTIED_obj((SV *)av,
902 NEGATIVE_INDICES_VAR, 16, 0);
903 if (negative_indices_glob
904 && SvTRUE(GvSV(*negative_indices_glob)))
908 key += AvFILL(av) + 1;
914 mg_copy((SV*)av, sv, 0, key);
915 mg = mg_find(sv, PERL_MAGIC_tiedelem);
917 magic_existspack(sv, mg);
918 return (bool)SvTRUE(sv);
925 key += AvFILL(av) + 1;
930 if (key <= AvFILLp(av) && AvARRAY(av)[key] != &PL_sv_undef
941 * c-indentation-style: bsd
943 * indent-tabs-mode: t
946 * ex: set ts=8 sts=4 sw=4 noet: