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)
34 if (SvTIED_mg((SV*)av, PERL_MAGIC_tied) && ckWARN_d(WARN_DEBUGGING))
35 Perl_warner(aTHX_ packWARN(WARN_DEBUGGING), "av_reify called on tied array");
38 while (key > AvFILLp(av) + 1)
39 AvARRAY(av)[--key] = &PL_sv_undef;
41 SV * const sv = AvARRAY(av)[--key];
43 if (sv != &PL_sv_undef)
44 (void)SvREFCNT_inc(sv);
46 key = AvARRAY(av) - AvALLOC(av);
48 AvALLOC(av)[--key] = &PL_sv_undef;
56 Pre-extend an array. The C<key> is the index to which the array should be
63 Perl_av_extend(pTHX_ AV *av, I32 key)
69 mg = SvTIED_mg((SV*)av, PERL_MAGIC_tied);
74 PUSHSTACKi(PERLSI_MAGIC);
77 PUSHs(SvTIED_obj((SV*)av, mg));
78 PUSHs(sv_2mortal(newSViv(key+1)));
80 call_method("EXTEND", G_SCALAR|G_DISCARD);
86 if (key > AvMAX(av)) {
91 if (AvALLOC(av) != AvARRAY(av)) {
92 ary = AvALLOC(av) + AvFILLp(av) + 1;
93 tmp = AvARRAY(av) - AvALLOC(av);
94 Move(AvARRAY(av), AvALLOC(av), AvFILLp(av)+1, SV*);
96 SvPV_set(av, (char*)AvALLOC(av));
99 ary[--tmp] = &PL_sv_undef;
101 if (key > AvMAX(av) - 10) {
102 newmax = key + AvMAX(av);
107 #ifdef PERL_MALLOC_WRAP
108 static const char oom_array_extend[] =
109 "Out of memory during array extend"; /* Duplicated in pp_hot.c */
113 #if !defined(STRANGE_MALLOC) && !defined(MYMALLOC)
119 newmax = malloced_size((void*)AvALLOC(av))/sizeof(SV*) - 1;
124 newmax = key + AvMAX(av) / 5;
126 MEM_WRAP_CHECK_1(newmax+1, SV*, oom_array_extend);
127 #if defined(STRANGE_MALLOC) || defined(MYMALLOC)
128 Renew(AvALLOC(av),newmax+1, SV*);
130 bytes = (newmax + 1) * sizeof(SV*);
131 #define MALLOC_OVERHEAD 16
132 itmp = MALLOC_OVERHEAD;
133 while ((MEM_SIZE)(itmp - MALLOC_OVERHEAD) < bytes)
135 itmp -= MALLOC_OVERHEAD;
137 assert(itmp > newmax);
139 assert(newmax >= AvMAX(av));
140 Newx(ary, newmax+1, SV*);
141 Copy(AvALLOC(av), ary, AvMAX(av)+1, SV*);
143 offer_nice_chunk(AvALLOC(av), (AvMAX(av)+1) * sizeof(SV*));
145 Safefree(AvALLOC(av));
151 ary = AvALLOC(av) + AvMAX(av) + 1;
152 tmp = newmax - AvMAX(av);
153 if (av == PL_curstack) { /* Oops, grew stack (via av_store()?) */
154 PL_stack_sp = AvALLOC(av) + (PL_stack_sp - PL_stack_base);
155 PL_stack_base = AvALLOC(av);
156 PL_stack_max = PL_stack_base + newmax;
160 newmax = key < 3 ? 3 : key;
161 MEM_WRAP_CHECK_1(newmax+1, SV*, oom_array_extend);
162 Newx(AvALLOC(av), newmax+1, SV*);
163 ary = AvALLOC(av) + 1;
165 AvALLOC(av)[0] = &PL_sv_undef; /* For the stacks */
169 ary[--tmp] = &PL_sv_undef;
172 SvPV_set(av, (char*)AvALLOC(av));
181 Returns the SV at the specified index in the array. The C<key> is the
182 index. If C<lval> is set then the fetch will be part of a store. Check
183 that the return value is non-null before dereferencing it to a C<SV*>.
185 See L<perlguts/"Understanding the Magic of Tied Hashes and Arrays"> for
186 more information on how to use this function on tied arrays.
192 Perl_av_fetch(pTHX_ register AV *av, I32 key, I32 lval)
198 if (SvRMAGICAL(av)) {
199 const MAGIC * const tied_magic = mg_find((SV*)av, PERL_MAGIC_tied);
200 if (tied_magic || mg_find((SV*)av, PERL_MAGIC_regdata)) {
201 U32 adjust_index = 1;
203 if (tied_magic && key < 0) {
204 /* Handle negative array indices 20020222 MJD */
205 SV * const * const negative_indices_glob =
206 hv_fetch(SvSTASH(SvRV(SvTIED_obj((SV *)av,
208 NEGATIVE_INDICES_VAR, 16, 0);
210 if (negative_indices_glob
211 && SvTRUE(GvSV(*negative_indices_glob)))
215 if (key < 0 && adjust_index) {
216 key += AvFILL(av) + 1;
222 sv_upgrade(sv, SVt_PVLV);
223 mg_copy((SV*)av, sv, 0, key);
225 LvTARG(sv) = sv; /* fake (SV**) */
226 return &(LvTARG(sv));
231 key += AvFILL(av) + 1;
236 if (key > AvFILLp(av)) {
240 return av_store(av,key,sv);
242 if (AvARRAY(av)[key] == &PL_sv_undef) {
246 return av_store(av,key,sv);
251 && (!AvARRAY(av)[key] /* eg. @_ could have freed elts */
252 || SvIS_FREED(AvARRAY(av)[key]))) {
253 AvARRAY(av)[key] = &PL_sv_undef; /* 1/2 reify */
256 return &AvARRAY(av)[key];
262 Stores an SV in an array. The array index is specified as C<key>. The
263 return value will be NULL if the operation failed or if the value did not
264 need to be actually stored within the array (as in the case of tied
265 arrays). Otherwise it can be dereferenced to get the original C<SV*>. Note
266 that the caller is responsible for suitably incrementing the reference
267 count of C<val> before the call, and decrementing it if the function
270 See L<perlguts/"Understanding the Magic of Tied Hashes and Arrays"> for
271 more information on how to use this function on tied arrays.
277 Perl_av_store(pTHX_ register AV *av, I32 key, SV *val)
286 if (SvRMAGICAL(av)) {
287 const MAGIC * const tied_magic = mg_find((SV*)av, PERL_MAGIC_tied);
289 /* Handle negative array indices 20020222 MJD */
291 unsigned adjust_index = 1;
292 SV * const * const negative_indices_glob =
293 hv_fetch(SvSTASH(SvRV(SvTIED_obj((SV *)av,
295 NEGATIVE_INDICES_VAR, 16, 0);
296 if (negative_indices_glob
297 && SvTRUE(GvSV(*negative_indices_glob)))
300 key += AvFILL(av) + 1;
305 if (val != &PL_sv_undef) {
306 mg_copy((SV*)av, val, 0, key);
314 key += AvFILL(av) + 1;
319 if (SvREADONLY(av) && key >= AvFILL(av))
320 Perl_croak(aTHX_ PL_no_modify);
322 if (!AvREAL(av) && AvREIFY(av))
327 if (AvFILLp(av) < key) {
329 if (av == PL_curstack && key > PL_stack_sp - PL_stack_base)
330 PL_stack_sp = PL_stack_base + key; /* XPUSH in disguise */
332 ary[++AvFILLp(av)] = &PL_sv_undef;
333 while (AvFILLp(av) < key);
338 SvREFCNT_dec(ary[key]);
340 if (SvSMAGICAL(av)) {
341 if (val != &PL_sv_undef) {
342 const MAGIC* const mg = SvMAGIC(av);
343 sv_magic(val, (SV*)av, toLOWER(mg->mg_type), 0, key);
353 Creates a new AV. The reference count is set to 1.
361 register AV * const av = (AV*)NEWSV(3,0);
363 sv_upgrade((SV *)av, SVt_PVAV);
364 /* sv_upgrade does AvREAL_only() */
366 SvPV_set(av, (char*)0);
367 AvMAX(av) = AvFILLp(av) = -1;
374 Creates a new AV and populates it with a list of SVs. The SVs are copied
375 into the array, so they may be freed after the call to av_make. The new AV
376 will have a reference count of 1.
382 Perl_av_make(pTHX_ register I32 size, register SV **strp)
384 register AV * const av = (AV*)NEWSV(8,0);
386 sv_upgrade((SV *) av,SVt_PVAV);
387 /* sv_upgrade does AvREAL_only() */
388 if (size) { /* "defined" was returning undef for size==0 anyway. */
393 SvPV_set(av, (char*)ary);
394 AvFILLp(av) = size - 1;
395 AvMAX(av) = size - 1;
396 for (i = 0; i < size; i++) {
399 sv_setsv(ary[i], *strp);
409 Clears an array, making it empty. Does not free the memory used by the
416 Perl_av_clear(pTHX_ register AV *av)
422 if (SvREFCNT(av) == 0 && ckWARN_d(WARN_DEBUGGING)) {
423 Perl_warner(aTHX_ packWARN(WARN_DEBUGGING), "Attempt to clear deleted array");
428 Perl_croak(aTHX_ PL_no_modify);
430 /* Give any tie a chance to cleanup first */
438 SV** const ary = AvARRAY(av);
439 key = AvFILLp(av) + 1;
441 SV * const sv = ary[--key];
442 /* undef the slot before freeing the value, because a
443 * destructor might try to modify this arrray */
444 ary[key] = &PL_sv_undef;
448 if ((key = AvARRAY(av) - AvALLOC(av))) {
450 SvPV_set(av, (char*)AvALLOC(av));
459 Undefines the array. Frees the memory used by the array itself.
465 Perl_av_undef(pTHX_ register AV *av)
469 /* Give any tie a chance to cleanup first */
470 if (SvTIED_mg((SV*)av, PERL_MAGIC_tied))
471 av_fill(av, -1); /* mg_clear() ? */
474 register I32 key = AvFILLp(av) + 1;
476 SvREFCNT_dec(AvARRAY(av)[--key]);
478 Safefree(AvALLOC(av));
480 SvPV_set(av, (char*)0);
481 AvMAX(av) = AvFILLp(av) = -1;
487 Pushes an SV onto the end of the array. The array will grow automatically
488 to accommodate the addition.
494 Perl_av_push(pTHX_ register AV *av, SV *val)
501 Perl_croak(aTHX_ PL_no_modify);
503 if ((mg = SvTIED_mg((SV*)av, PERL_MAGIC_tied))) {
505 PUSHSTACKi(PERLSI_MAGIC);
508 PUSHs(SvTIED_obj((SV*)av, mg));
512 call_method("PUSH", G_SCALAR|G_DISCARD);
517 av_store(av,AvFILLp(av)+1,val);
523 Pops an SV off the end of the array. Returns C<&PL_sv_undef> if the array
530 Perl_av_pop(pTHX_ register AV *av)
539 Perl_croak(aTHX_ PL_no_modify);
540 if ((mg = SvTIED_mg((SV*)av, PERL_MAGIC_tied))) {
542 PUSHSTACKi(PERLSI_MAGIC);
544 XPUSHs(SvTIED_obj((SV*)av, mg));
547 if (call_method("POP", G_SCALAR)) {
548 retval = newSVsv(*PL_stack_sp--);
550 retval = &PL_sv_undef;
558 retval = AvARRAY(av)[AvFILLp(av)];
559 AvARRAY(av)[AvFILLp(av)--] = &PL_sv_undef;
566 =for apidoc av_unshift
568 Unshift the given number of C<undef> values onto the beginning of the
569 array. The array will grow automatically to accommodate the addition. You
570 must then use C<av_store> to assign values to these new elements.
576 Perl_av_unshift(pTHX_ register AV *av, register I32 num)
585 Perl_croak(aTHX_ PL_no_modify);
587 if ((mg = SvTIED_mg((SV*)av, PERL_MAGIC_tied))) {
589 PUSHSTACKi(PERLSI_MAGIC);
592 PUSHs(SvTIED_obj((SV*)av, mg));
598 call_method("UNSHIFT", G_SCALAR|G_DISCARD);
606 if (!AvREAL(av) && AvREIFY(av))
608 i = AvARRAY(av) - AvALLOC(av);
616 SvPV_set(av, (char*)(AvARRAY(av) - i));
622 /* Create extra elements */
623 slide = i > 0 ? i : 0;
625 av_extend(av, i + num);
628 Move(ary, ary + num, i + 1, SV*);
630 ary[--num] = &PL_sv_undef;
632 /* Make extra elements into a buffer */
634 AvFILLp(av) -= slide;
635 SvPV_set(av, (char*)(AvARRAY(av) + slide));
642 Shifts an SV off the beginning of the array.
648 Perl_av_shift(pTHX_ register AV *av)
657 Perl_croak(aTHX_ PL_no_modify);
658 if ((mg = SvTIED_mg((SV*)av, PERL_MAGIC_tied))) {
660 PUSHSTACKi(PERLSI_MAGIC);
662 XPUSHs(SvTIED_obj((SV*)av, mg));
665 if (call_method("SHIFT", G_SCALAR)) {
666 retval = newSVsv(*PL_stack_sp--);
668 retval = &PL_sv_undef;
676 retval = *AvARRAY(av);
678 *AvARRAY(av) = &PL_sv_undef;
679 SvPV_set(av, (char*)(AvARRAY(av) + 1));
690 Returns the highest index in the array. Returns -1 if the array is
697 Perl_av_len(pTHX_ register const AV *av)
706 Ensure than an array has a given number of elements, equivalent to
707 Perl's C<$#array = $fill;>.
712 Perl_av_fill(pTHX_ register AV *av, I32 fill)
721 if ((mg = SvTIED_mg((SV*)av, PERL_MAGIC_tied))) {
725 PUSHSTACKi(PERLSI_MAGIC);
728 PUSHs(SvTIED_obj((SV*)av, mg));
729 PUSHs(sv_2mortal(newSViv(fill+1)));
731 call_method("STORESIZE", G_SCALAR|G_DISCARD);
737 if (fill <= AvMAX(av)) {
738 I32 key = AvFILLp(av);
739 SV** const ary = AvARRAY(av);
743 SvREFCNT_dec(ary[key]);
744 ary[key--] = &PL_sv_undef;
749 ary[++key] = &PL_sv_undef;
757 (void)av_store(av,fill,&PL_sv_undef);
761 =for apidoc av_delete
763 Deletes the element indexed by C<key> from the array. Returns the
764 deleted element. If C<flags> equals C<G_DISCARD>, the element is freed
765 and null is returned.
770 Perl_av_delete(pTHX_ AV *av, I32 key, I32 flags)
777 Perl_croak(aTHX_ PL_no_modify);
779 if (SvRMAGICAL(av)) {
780 const MAGIC * const tied_magic = mg_find((SV*)av, PERL_MAGIC_tied);
781 if ((tied_magic || mg_find((SV*)av, PERL_MAGIC_regdata))) {
782 /* Handle negative array indices 20020222 MJD */
785 unsigned adjust_index = 1;
787 SV * const * const negative_indices_glob =
788 hv_fetch(SvSTASH(SvRV(SvTIED_obj((SV *)av,
790 NEGATIVE_INDICES_VAR, 16, 0);
791 if (negative_indices_glob
792 && SvTRUE(GvSV(*negative_indices_glob)))
796 key += AvFILL(av) + 1;
801 svp = av_fetch(av, key, TRUE);
805 if (mg_find(sv, PERL_MAGIC_tiedelem)) {
806 sv_unmagic(sv, PERL_MAGIC_tiedelem); /* No longer an element */
815 key += AvFILL(av) + 1;
820 if (key > AvFILLp(av))
823 if (!AvREAL(av) && AvREIFY(av))
825 sv = AvARRAY(av)[key];
826 if (key == AvFILLp(av)) {
827 AvARRAY(av)[key] = &PL_sv_undef;
830 } while (--key >= 0 && AvARRAY(av)[key] == &PL_sv_undef);
833 AvARRAY(av)[key] = &PL_sv_undef;
837 if (flags & G_DISCARD) {
847 =for apidoc av_exists
849 Returns true if the element indexed by C<key> has been initialized.
851 This relies on the fact that uninitialized array elements are set to
857 Perl_av_exists(pTHX_ AV *av, I32 key)
861 if (SvRMAGICAL(av)) {
862 const MAGIC * const tied_magic = mg_find((SV*)av, PERL_MAGIC_tied);
863 if (tied_magic || mg_find((SV*)av, PERL_MAGIC_regdata)) {
864 SV * const sv = sv_newmortal();
866 /* Handle negative array indices 20020222 MJD */
868 unsigned adjust_index = 1;
870 SV * const * const negative_indices_glob =
871 hv_fetch(SvSTASH(SvRV(SvTIED_obj((SV *)av,
873 NEGATIVE_INDICES_VAR, 16, 0);
874 if (negative_indices_glob
875 && SvTRUE(GvSV(*negative_indices_glob)))
879 key += AvFILL(av) + 1;
885 mg_copy((SV*)av, sv, 0, key);
886 mg = mg_find(sv, PERL_MAGIC_tiedelem);
888 magic_existspack(sv, mg);
889 return (bool)SvTRUE(sv);
896 key += AvFILL(av) + 1;
901 if (key <= AvFILLp(av) && AvARRAY(av)[key] != &PL_sv_undef
911 Perl_av_arylen_p(pTHX_ AV *av) {
917 mg = mg_find((SV*)av, PERL_MAGIC_arylen_p);
920 mg = sv_magicext((SV*)av, 0, PERL_MAGIC_arylen_p, &PL_vtbl_arylen_p,
923 /* sv_magicext won't set this for us because we pass in a NULL obj */
924 mg->mg_flags |= MGf_REFCOUNTED;
926 return &(mg->mg_obj);
931 * c-indentation-style: bsd
933 * indent-tabs-mode: t
936 * ex: set ts=8 sts=4 sw=4 noet: