3 * Copyright (C) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
4 * 2000, 2001, 2002, 2003, 2004, 2005, 2006, 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)
35 if (SvTIED_mg((SV*)av, PERL_MAGIC_tied) && ckWARN_d(WARN_DEBUGGING))
36 Perl_warner(aTHX_ packWARN(WARN_DEBUGGING), "av_reify called on tied array");
39 while (key > AvFILLp(av) + 1)
40 AvARRAY(av)[--key] = &PL_sv_undef;
42 SV * const sv = AvARRAY(av)[--key];
44 if (sv != &PL_sv_undef)
45 SvREFCNT_inc_simple_void_NN(sv);
47 key = AvARRAY(av) - AvALLOC(av);
49 AvALLOC(av)[--key] = &PL_sv_undef;
57 Pre-extend an array. The C<key> is the index to which the array should be
64 Perl_av_extend(pTHX_ AV *av, I32 key)
71 mg = SvTIED_mg((SV*)av, PERL_MAGIC_tied);
76 PUSHSTACKi(PERLSI_MAGIC);
79 PUSHs(SvTIED_obj((SV*)av, mg));
80 PUSHs(sv_2mortal(newSViv(key+1)));
82 call_method("EXTEND", G_SCALAR|G_DISCARD);
88 if (key > AvMAX(av)) {
93 if (AvALLOC(av) != AvARRAY(av)) {
94 ary = AvALLOC(av) + AvFILLp(av) + 1;
95 tmp = AvARRAY(av) - AvALLOC(av);
96 Move(AvARRAY(av), AvALLOC(av), AvFILLp(av)+1, SV*);
98 AvARRAY(av) = AvALLOC(av);
101 ary[--tmp] = &PL_sv_undef;
103 if (key > AvMAX(av) - 10) {
104 newmax = key + AvMAX(av);
109 #ifdef PERL_MALLOC_WRAP
110 static const char oom_array_extend[] =
111 "Out of memory during array extend"; /* Duplicated in pp_hot.c */
115 #if !defined(STRANGE_MALLOC) && !defined(MYMALLOC)
121 newmax = malloced_size((void*)AvALLOC(av))/sizeof(SV*) - 1;
126 newmax = key + AvMAX(av) / 5;
128 MEM_WRAP_CHECK_1(newmax+1, SV*, oom_array_extend);
129 #if defined(STRANGE_MALLOC) || defined(MYMALLOC)
130 Renew(AvALLOC(av),newmax+1, SV*);
132 bytes = (newmax + 1) * sizeof(SV*);
133 #define MALLOC_OVERHEAD 16
134 itmp = MALLOC_OVERHEAD;
135 while ((MEM_SIZE)(itmp - MALLOC_OVERHEAD) < bytes)
137 itmp -= MALLOC_OVERHEAD;
139 assert(itmp > newmax);
141 assert(newmax >= AvMAX(av));
142 Newx(ary, newmax+1, SV*);
143 Copy(AvALLOC(av), ary, AvMAX(av)+1, SV*);
145 offer_nice_chunk(AvALLOC(av), (AvMAX(av)+1) * sizeof(SV*));
147 Safefree(AvALLOC(av));
153 ary = AvALLOC(av) + AvMAX(av) + 1;
154 tmp = newmax - AvMAX(av);
155 if (av == PL_curstack) { /* Oops, grew stack (via av_store()?) */
156 PL_stack_sp = AvALLOC(av) + (PL_stack_sp - PL_stack_base);
157 PL_stack_base = AvALLOC(av);
158 PL_stack_max = PL_stack_base + newmax;
162 newmax = key < 3 ? 3 : key;
163 MEM_WRAP_CHECK_1(newmax+1, SV*, oom_array_extend);
164 Newx(AvALLOC(av), newmax+1, SV*);
165 ary = AvALLOC(av) + 1;
167 AvALLOC(av)[0] = &PL_sv_undef; /* For the stacks */
171 ary[--tmp] = &PL_sv_undef;
174 AvARRAY(av) = AvALLOC(av);
183 Returns the SV at the specified index in the array. The C<key> is the
184 index. If C<lval> is set then the fetch will be part of a store. Check
185 that the return value is non-null before dereferencing it to a C<SV*>.
187 See L<perlguts/"Understanding the Magic of Tied Hashes and Arrays"> for
188 more information on how to use this function on tied arrays.
194 Perl_av_fetch(pTHX_ register AV *av, I32 key, I32 lval)
200 if (SvRMAGICAL(av)) {
201 const MAGIC * const tied_magic = mg_find((SV*)av, PERL_MAGIC_tied);
202 if (tied_magic || mg_find((SV*)av, PERL_MAGIC_regdata)) {
205 I32 adjust_index = 1;
207 /* Handle negative array indices 20020222 MJD */
208 SV * const * const negative_indices_glob =
209 hv_fetch(SvSTASH(SvRV(SvTIED_obj((SV *)av, tied_magic))),
210 NEGATIVE_INDICES_VAR, 16, 0);
212 if (negative_indices_glob && SvTRUE(GvSV(*negative_indices_glob)))
217 key += AvFILL(av) + 1;
224 sv_upgrade(sv, SVt_PVLV);
225 mg_copy((SV*)av, sv, 0, key);
227 LvTARG(sv) = sv; /* fake (SV**) */
228 return &(LvTARG(sv));
233 key += AvFILL(av) + 1;
238 if (key > AvFILLp(av)) {
241 return av_store(av,key,newSV(0));
243 if (AvARRAY(av)[key] == &PL_sv_undef) {
246 return av_store(av,key,newSV(0));
250 && (!AvARRAY(av)[key] /* eg. @_ could have freed elts */
251 || SvIS_FREED(AvARRAY(av)[key]))) {
252 AvARRAY(av)[key] = &PL_sv_undef; /* 1/2 reify */
255 return &AvARRAY(av)[key];
261 Stores an SV in an array. The array index is specified as C<key>. The
262 return value will be NULL if the operation failed or if the value did not
263 need to be actually stored within the array (as in the case of tied
264 arrays). Otherwise it can be dereferenced to get the original C<SV*>. Note
265 that the caller is responsible for suitably incrementing the reference
266 count of C<val> before the call, and decrementing it if the function
269 See L<perlguts/"Understanding the Magic of Tied Hashes and Arrays"> for
270 more information on how to use this function on tied arrays.
276 Perl_av_store(pTHX_ register AV *av, I32 key, SV *val)
283 /* S_regclass relies on being able to pass in a NULL sv
284 (unicode_alternate may be NULL).
290 if (SvRMAGICAL(av)) {
291 const MAGIC * const tied_magic = mg_find((SV*)av, PERL_MAGIC_tied);
293 /* Handle negative array indices 20020222 MJD */
295 bool adjust_index = 1;
296 SV * const * const negative_indices_glob =
297 hv_fetch(SvSTASH(SvRV(SvTIED_obj((SV *)av,
299 NEGATIVE_INDICES_VAR, 16, 0);
300 if (negative_indices_glob
301 && SvTRUE(GvSV(*negative_indices_glob)))
304 key += AvFILL(av) + 1;
309 if (val != &PL_sv_undef) {
310 mg_copy((SV*)av, val, 0, key);
318 key += AvFILL(av) + 1;
323 if (SvREADONLY(av) && key >= AvFILL(av))
324 Perl_croak(aTHX_ PL_no_modify);
326 if (!AvREAL(av) && AvREIFY(av))
331 if (AvFILLp(av) < key) {
333 if (av == PL_curstack && key > PL_stack_sp - PL_stack_base)
334 PL_stack_sp = PL_stack_base + key; /* XPUSH in disguise */
336 ary[++AvFILLp(av)] = &PL_sv_undef;
337 } while (AvFILLp(av) < key);
342 SvREFCNT_dec(ary[key]);
344 if (SvSMAGICAL(av)) {
345 if (val != &PL_sv_undef) {
346 const MAGIC* const mg = SvMAGIC(av);
347 sv_magic(val, (SV*)av, toLOWER(mg->mg_type), 0, key);
357 Creates a new AV. The reference count is set to 1.
365 register AV * const av = (AV*)newSV(0);
367 sv_upgrade((SV *)av, SVt_PVAV);
368 /* sv_upgrade does AvREAL_only() */
371 AvMAX(av) = AvFILLp(av) = -1;
378 Creates a new AV and populates it with a list of SVs. The SVs are copied
379 into the array, so they may be freed after the call to av_make. The new AV
380 will have a reference count of 1.
386 Perl_av_make(pTHX_ register I32 size, register SV **strp)
388 register AV * const av = (AV*)newSV(0);
390 sv_upgrade((SV *) av,SVt_PVAV);
391 /* sv_upgrade does AvREAL_only() */
392 if (size) { /* "defined" was returning undef for size==0 anyway. */
398 AvFILLp(av) = AvMAX(av) = size - 1;
399 for (i = 0; i < size; i++) {
402 sv_setsv(ary[i], *strp);
412 Clears an array, making it empty. Does not free the memory used by the
419 Perl_av_clear(pTHX_ register AV *av)
426 if (SvREFCNT(av) == 0 && ckWARN_d(WARN_DEBUGGING)) {
427 Perl_warner(aTHX_ packWARN(WARN_DEBUGGING), "Attempt to clear deleted array");
432 Perl_croak(aTHX_ PL_no_modify);
434 /* Give any tie a chance to cleanup first */
442 SV** const ary = AvARRAY(av);
443 I32 index = AvFILLp(av) + 1;
445 SV * const sv = ary[--index];
446 /* undef the slot before freeing the value, because a
447 * destructor might try to modify this array */
448 ary[index] = &PL_sv_undef;
452 extra = AvARRAY(av) - AvALLOC(av);
455 AvARRAY(av) = AvALLOC(av);
464 Undefines the array. Frees the memory used by the array itself.
470 Perl_av_undef(pTHX_ register AV *av)
474 /* Give any tie a chance to cleanup first */
475 if (SvTIED_mg((SV*)av, PERL_MAGIC_tied))
476 av_fill(av, -1); /* mg_clear() ? */
479 register I32 key = AvFILLp(av) + 1;
481 SvREFCNT_dec(AvARRAY(av)[--key]);
483 Safefree(AvALLOC(av));
486 AvMAX(av) = AvFILLp(av) = -1;
491 =for apidoc av_create_and_push
493 Push an SV onto the end of the array, creating the array if necessary.
494 A small internal helper function to remove a commonly duplicated idiom.
500 Perl_av_create_and_push(pTHX_ AV **const avp, SV *const val)
510 Pushes an SV onto the end of the array. The array will grow automatically
511 to accommodate the addition.
517 Perl_av_push(pTHX_ register AV *av, SV *val)
524 Perl_croak(aTHX_ PL_no_modify);
526 if ((mg = SvTIED_mg((SV*)av, PERL_MAGIC_tied))) {
528 PUSHSTACKi(PERLSI_MAGIC);
531 PUSHs(SvTIED_obj((SV*)av, mg));
535 call_method("PUSH", G_SCALAR|G_DISCARD);
540 av_store(av,AvFILLp(av)+1,val);
546 Pops an SV off the end of the array. Returns C<&PL_sv_undef> if the array
553 Perl_av_pop(pTHX_ register AV *av)
562 Perl_croak(aTHX_ PL_no_modify);
563 if ((mg = SvTIED_mg((SV*)av, PERL_MAGIC_tied))) {
565 PUSHSTACKi(PERLSI_MAGIC);
567 XPUSHs(SvTIED_obj((SV*)av, mg));
570 if (call_method("POP", G_SCALAR)) {
571 retval = newSVsv(*PL_stack_sp--);
573 retval = &PL_sv_undef;
581 retval = AvARRAY(av)[AvFILLp(av)];
582 AvARRAY(av)[AvFILLp(av)--] = &PL_sv_undef;
590 =for apidoc av_create_and_unshift_one
592 Unshifts an SV onto the beginning of the array, creating the array if
594 A small internal helper function to remove a commonly duplicated idiom.
600 Perl_av_create_and_unshift_one(pTHX_ AV **const avp, SV *const val)
605 return av_store(*avp, 0, val);
609 =for apidoc av_unshift
611 Unshift the given number of C<undef> values onto the beginning of the
612 array. The array will grow automatically to accommodate the addition. You
613 must then use C<av_store> to assign values to these new elements.
619 Perl_av_unshift(pTHX_ register AV *av, register I32 num)
628 Perl_croak(aTHX_ PL_no_modify);
630 if ((mg = SvTIED_mg((SV*)av, PERL_MAGIC_tied))) {
632 PUSHSTACKi(PERLSI_MAGIC);
635 PUSHs(SvTIED_obj((SV*)av, mg));
641 call_method("UNSHIFT", G_SCALAR|G_DISCARD);
649 if (!AvREAL(av) && AvREIFY(av))
651 i = AvARRAY(av) - AvALLOC(av);
659 AvARRAY(av) = AvARRAY(av) - i;
665 /* Create extra elements */
666 slide = i > 0 ? i : 0;
668 av_extend(av, i + num);
671 Move(ary, ary + num, i + 1, SV*);
673 ary[--num] = &PL_sv_undef;
675 /* Make extra elements into a buffer */
677 AvFILLp(av) -= slide;
678 AvARRAY(av) = AvARRAY(av) + slide;
685 Shifts an SV off the beginning of the array.
691 Perl_av_shift(pTHX_ register AV *av)
700 Perl_croak(aTHX_ PL_no_modify);
701 if ((mg = SvTIED_mg((SV*)av, PERL_MAGIC_tied))) {
703 PUSHSTACKi(PERLSI_MAGIC);
705 XPUSHs(SvTIED_obj((SV*)av, mg));
708 if (call_method("SHIFT", G_SCALAR)) {
709 retval = newSVsv(*PL_stack_sp--);
711 retval = &PL_sv_undef;
719 retval = *AvARRAY(av);
721 *AvARRAY(av) = &PL_sv_undef;
722 AvARRAY(av) = AvARRAY(av) + 1;
733 Returns the highest index in the array. The number of elements in the
734 array is C<av_len(av) + 1>. Returns -1 if the array is empty.
740 Perl_av_len(pTHX_ register const AV *av)
749 Set the highest index in the array to the given number, equivalent to
750 Perl's C<$#array = $fill;>.
752 The number of elements in the an array will be C<fill + 1> after
753 av_fill() returns. If the array was previously shorter then the
754 additional elements appended are set to C<PL_sv_undef>. If the array
755 was longer, then the excess elements are freed. C<av_fill(av, -1)> is
756 the same as C<av_clear(av)>.
761 Perl_av_fill(pTHX_ register AV *av, I32 fill)
770 if ((mg = SvTIED_mg((SV*)av, PERL_MAGIC_tied))) {
774 PUSHSTACKi(PERLSI_MAGIC);
777 PUSHs(SvTIED_obj((SV*)av, mg));
778 PUSHs(sv_2mortal(newSViv(fill+1)));
780 call_method("STORESIZE", G_SCALAR|G_DISCARD);
786 if (fill <= AvMAX(av)) {
787 I32 key = AvFILLp(av);
788 SV** const ary = AvARRAY(av);
792 SvREFCNT_dec(ary[key]);
793 ary[key--] = &PL_sv_undef;
798 ary[++key] = &PL_sv_undef;
806 (void)av_store(av,fill,&PL_sv_undef);
810 =for apidoc av_delete
812 Deletes the element indexed by C<key> from the array. Returns the
813 deleted element. If C<flags> equals C<G_DISCARD>, the element is freed
814 and null is returned.
819 Perl_av_delete(pTHX_ AV *av, I32 key, I32 flags)
827 Perl_croak(aTHX_ PL_no_modify);
829 if (SvRMAGICAL(av)) {
830 const MAGIC * const tied_magic = mg_find((SV*)av, PERL_MAGIC_tied);
831 if ((tied_magic || mg_find((SV*)av, PERL_MAGIC_regdata))) {
832 /* Handle negative array indices 20020222 MJD */
835 unsigned adjust_index = 1;
837 SV * const * const negative_indices_glob =
838 hv_fetch(SvSTASH(SvRV(SvTIED_obj((SV *)av,
840 NEGATIVE_INDICES_VAR, 16, 0);
841 if (negative_indices_glob
842 && SvTRUE(GvSV(*negative_indices_glob)))
846 key += AvFILL(av) + 1;
851 svp = av_fetch(av, key, TRUE);
855 if (mg_find(sv, PERL_MAGIC_tiedelem)) {
856 sv_unmagic(sv, PERL_MAGIC_tiedelem); /* No longer an element */
865 key += AvFILL(av) + 1;
870 if (key > AvFILLp(av))
873 if (!AvREAL(av) && AvREIFY(av))
875 sv = AvARRAY(av)[key];
876 if (key == AvFILLp(av)) {
877 AvARRAY(av)[key] = &PL_sv_undef;
880 } while (--key >= 0 && AvARRAY(av)[key] == &PL_sv_undef);
883 AvARRAY(av)[key] = &PL_sv_undef;
887 if (flags & G_DISCARD) {
897 =for apidoc av_exists
899 Returns true if the element indexed by C<key> has been initialized.
901 This relies on the fact that uninitialized array elements are set to
907 Perl_av_exists(pTHX_ AV *av, I32 key)
912 if (SvRMAGICAL(av)) {
913 const MAGIC * const tied_magic = mg_find((SV*)av, PERL_MAGIC_tied);
914 if (tied_magic || mg_find((SV*)av, PERL_MAGIC_regdata)) {
915 SV * const sv = sv_newmortal();
917 /* Handle negative array indices 20020222 MJD */
919 unsigned adjust_index = 1;
921 SV * const * const negative_indices_glob =
922 hv_fetch(SvSTASH(SvRV(SvTIED_obj((SV *)av,
924 NEGATIVE_INDICES_VAR, 16, 0);
925 if (negative_indices_glob
926 && SvTRUE(GvSV(*negative_indices_glob)))
930 key += AvFILL(av) + 1;
936 mg_copy((SV*)av, sv, 0, key);
937 mg = mg_find(sv, PERL_MAGIC_tiedelem);
939 magic_existspack(sv, mg);
940 return (bool)SvTRUE(sv);
947 key += AvFILL(av) + 1;
952 if (key <= AvFILLp(av) && AvARRAY(av)[key] != &PL_sv_undef
962 Perl_av_arylen_p(pTHX_ AV *av) {
968 mg = mg_find((SV*)av, PERL_MAGIC_arylen_p);
971 mg = sv_magicext((SV*)av, 0, PERL_MAGIC_arylen_p, &PL_vtbl_arylen_p,
974 /* sv_magicext won't set this for us because we pass in a NULL obj */
975 mg->mg_flags |= MGf_REFCOUNTED;
977 return &(mg->mg_obj);
982 * c-indentation-style: bsd
984 * indent-tabs-mode: t
987 * ex: set ts=8 sts=4 sw=4 noet: