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_type(SVt_PVAV);
366 /* sv_upgrade does AvREAL_only() */
369 AvMAX(av) = AvFILLp(av) = -1;
376 Creates a new AV and populates it with a list of SVs. The SVs are copied
377 into the array, so they may be freed after the call to av_make. The new AV
378 will have a reference count of 1.
384 Perl_av_make(pTHX_ register I32 size, register SV **strp)
386 register AV * const av = (AV*)newSV_type(SVt_PVAV);
387 /* sv_upgrade does AvREAL_only() */
388 if (size) { /* "defined" was returning undef for size==0 anyway. */
394 AvFILLp(av) = AvMAX(av) = size - 1;
395 for (i = 0; i < size; i++) {
398 sv_setsv(ary[i], *strp);
408 Clears an array, making it empty. Does not free the memory used by the
415 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 I32 index = AvFILLp(av) + 1;
441 SV * const sv = ary[--index];
442 /* undef the slot before freeing the value, because a
443 * destructor might try to modify this array */
444 ary[index] = &PL_sv_undef;
448 extra = AvARRAY(av) - AvALLOC(av);
451 AvARRAY(av) = AvALLOC(av);
460 Undefines the array. Frees the memory used by the array itself.
466 Perl_av_undef(pTHX_ register AV *av)
470 /* Give any tie a chance to cleanup first */
471 if (SvTIED_mg((SV*)av, PERL_MAGIC_tied))
472 av_fill(av, -1); /* mg_clear() ? */
475 register I32 key = AvFILLp(av) + 1;
477 SvREFCNT_dec(AvARRAY(av)[--key]);
479 Safefree(AvALLOC(av));
482 AvMAX(av) = AvFILLp(av) = -1;
487 =for apidoc av_create_and_push
489 Push an SV onto the end of the array, creating the array if necessary.
490 A small internal helper function to remove a commonly duplicated idiom.
496 Perl_av_create_and_push(pTHX_ AV **const avp, SV *const val)
506 Pushes an SV onto the end of the array. The array will grow automatically
507 to accommodate the addition.
513 Perl_av_push(pTHX_ register AV *av, SV *val)
520 Perl_croak(aTHX_ PL_no_modify);
522 if ((mg = SvTIED_mg((SV*)av, PERL_MAGIC_tied))) {
524 PUSHSTACKi(PERLSI_MAGIC);
527 PUSHs(SvTIED_obj((SV*)av, mg));
531 call_method("PUSH", G_SCALAR|G_DISCARD);
536 av_store(av,AvFILLp(av)+1,val);
542 Pops an SV off the end of the array. Returns C<&PL_sv_undef> if the array
549 Perl_av_pop(pTHX_ register AV *av)
558 Perl_croak(aTHX_ PL_no_modify);
559 if ((mg = SvTIED_mg((SV*)av, PERL_MAGIC_tied))) {
561 PUSHSTACKi(PERLSI_MAGIC);
563 XPUSHs(SvTIED_obj((SV*)av, mg));
566 if (call_method("POP", G_SCALAR)) {
567 retval = newSVsv(*PL_stack_sp--);
569 retval = &PL_sv_undef;
577 retval = AvARRAY(av)[AvFILLp(av)];
578 AvARRAY(av)[AvFILLp(av)--] = &PL_sv_undef;
586 =for apidoc av_create_and_unshift_one
588 Unshifts an SV onto the beginning of the array, creating the array if
590 A small internal helper function to remove a commonly duplicated idiom.
596 Perl_av_create_and_unshift_one(pTHX_ AV **const avp, SV *const val)
601 return av_store(*avp, 0, val);
605 =for apidoc av_unshift
607 Unshift the given number of C<undef> values onto the beginning of the
608 array. The array will grow automatically to accommodate the addition. You
609 must then use C<av_store> to assign values to these new elements.
615 Perl_av_unshift(pTHX_ register AV *av, register I32 num)
624 Perl_croak(aTHX_ PL_no_modify);
626 if ((mg = SvTIED_mg((SV*)av, PERL_MAGIC_tied))) {
628 PUSHSTACKi(PERLSI_MAGIC);
631 PUSHs(SvTIED_obj((SV*)av, mg));
637 call_method("UNSHIFT", G_SCALAR|G_DISCARD);
645 if (!AvREAL(av) && AvREIFY(av))
647 i = AvARRAY(av) - AvALLOC(av);
655 AvARRAY(av) = AvARRAY(av) - i;
659 const I32 i = AvFILLp(av);
660 /* Create extra elements */
661 const I32 slide = i > 0 ? i : 0;
663 av_extend(av, i + num);
666 Move(ary, ary + num, i + 1, SV*);
668 ary[--num] = &PL_sv_undef;
670 /* Make extra elements into a buffer */
672 AvFILLp(av) -= slide;
673 AvARRAY(av) = AvARRAY(av) + slide;
680 Shifts an SV off the beginning of the array.
686 Perl_av_shift(pTHX_ register AV *av)
695 Perl_croak(aTHX_ PL_no_modify);
696 if ((mg = SvTIED_mg((SV*)av, PERL_MAGIC_tied))) {
698 PUSHSTACKi(PERLSI_MAGIC);
700 XPUSHs(SvTIED_obj((SV*)av, mg));
703 if (call_method("SHIFT", G_SCALAR)) {
704 retval = newSVsv(*PL_stack_sp--);
706 retval = &PL_sv_undef;
714 retval = *AvARRAY(av);
716 *AvARRAY(av) = &PL_sv_undef;
717 AvARRAY(av) = AvARRAY(av) + 1;
728 Returns the highest index in the array. The number of elements in the
729 array is C<av_len(av) + 1>. Returns -1 if the array is empty.
735 Perl_av_len(pTHX_ register const AV *av)
744 Set the highest index in the array to the given number, equivalent to
745 Perl's C<$#array = $fill;>.
747 The number of elements in the an array will be C<fill + 1> after
748 av_fill() returns. If the array was previously shorter then the
749 additional elements appended are set to C<PL_sv_undef>. If the array
750 was longer, then the excess elements are freed. C<av_fill(av, -1)> is
751 the same as C<av_clear(av)>.
756 Perl_av_fill(pTHX_ register AV *av, I32 fill)
765 if ((mg = SvTIED_mg((SV*)av, PERL_MAGIC_tied))) {
769 PUSHSTACKi(PERLSI_MAGIC);
772 PUSHs(SvTIED_obj((SV*)av, mg));
773 PUSHs(sv_2mortal(newSViv(fill+1)));
775 call_method("STORESIZE", G_SCALAR|G_DISCARD);
781 if (fill <= AvMAX(av)) {
782 I32 key = AvFILLp(av);
783 SV** const ary = AvARRAY(av);
787 SvREFCNT_dec(ary[key]);
788 ary[key--] = &PL_sv_undef;
793 ary[++key] = &PL_sv_undef;
801 (void)av_store(av,fill,&PL_sv_undef);
805 =for apidoc av_delete
807 Deletes the element indexed by C<key> from the array. Returns the
808 deleted element. If C<flags> equals C<G_DISCARD>, the element is freed
809 and null is returned.
814 Perl_av_delete(pTHX_ AV *av, I32 key, I32 flags)
822 Perl_croak(aTHX_ PL_no_modify);
824 if (SvRMAGICAL(av)) {
825 const MAGIC * const tied_magic = mg_find((SV*)av, PERL_MAGIC_tied);
826 if ((tied_magic || mg_find((SV*)av, PERL_MAGIC_regdata))) {
827 /* Handle negative array indices 20020222 MJD */
830 unsigned adjust_index = 1;
832 SV * const * const negative_indices_glob =
833 hv_fetch(SvSTASH(SvRV(SvTIED_obj((SV *)av,
835 NEGATIVE_INDICES_VAR, 16, 0);
836 if (negative_indices_glob
837 && SvTRUE(GvSV(*negative_indices_glob)))
841 key += AvFILL(av) + 1;
846 svp = av_fetch(av, key, TRUE);
850 if (mg_find(sv, PERL_MAGIC_tiedelem)) {
851 sv_unmagic(sv, PERL_MAGIC_tiedelem); /* No longer an element */
860 key += AvFILL(av) + 1;
865 if (key > AvFILLp(av))
868 if (!AvREAL(av) && AvREIFY(av))
870 sv = AvARRAY(av)[key];
871 if (key == AvFILLp(av)) {
872 AvARRAY(av)[key] = &PL_sv_undef;
875 } while (--key >= 0 && AvARRAY(av)[key] == &PL_sv_undef);
878 AvARRAY(av)[key] = &PL_sv_undef;
882 if (flags & G_DISCARD) {
892 =for apidoc av_exists
894 Returns true if the element indexed by C<key> has been initialized.
896 This relies on the fact that uninitialized array elements are set to
902 Perl_av_exists(pTHX_ AV *av, I32 key)
907 if (SvRMAGICAL(av)) {
908 const MAGIC * const tied_magic = mg_find((SV*)av, PERL_MAGIC_tied);
909 if (tied_magic || mg_find((SV*)av, PERL_MAGIC_regdata)) {
910 SV * const sv = sv_newmortal();
912 /* Handle negative array indices 20020222 MJD */
914 unsigned adjust_index = 1;
916 SV * const * const negative_indices_glob =
917 hv_fetch(SvSTASH(SvRV(SvTIED_obj((SV *)av,
919 NEGATIVE_INDICES_VAR, 16, 0);
920 if (negative_indices_glob
921 && SvTRUE(GvSV(*negative_indices_glob)))
925 key += AvFILL(av) + 1;
931 mg_copy((SV*)av, sv, 0, key);
932 mg = mg_find(sv, PERL_MAGIC_tiedelem);
934 magic_existspack(sv, mg);
935 return (bool)SvTRUE(sv);
942 key += AvFILL(av) + 1;
947 if (key <= AvFILLp(av) && AvARRAY(av)[key] != &PL_sv_undef
957 Perl_av_arylen_p(pTHX_ AV *av) {
963 mg = mg_find((SV*)av, PERL_MAGIC_arylen_p);
966 mg = sv_magicext((SV*)av, 0, PERL_MAGIC_arylen_p, &PL_vtbl_arylen_p,
969 /* sv_magicext won't set this for us because we pass in a NULL obj */
970 mg->mg_flags |= MGf_REFCOUNTED;
972 return &(mg->mg_obj);
977 * c-indentation-style: bsd
979 * indent-tabs-mode: t
982 * ex: set ts=8 sts=4 sw=4 noet: