3 * Copyright (C) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
4 * 2000, 2001, 2002, 2003, 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)
33 if (SvTIED_mg((SV*)av, PERL_MAGIC_tied) && ckWARN_d(WARN_DEBUGGING))
34 Perl_warner(aTHX_ packWARN(WARN_DEBUGGING), "av_reify called on tied array");
37 while (key > AvFILLp(av) + 1)
38 AvARRAY(av)[--key] = &PL_sv_undef;
40 sv = AvARRAY(av)[--key];
42 if (sv != &PL_sv_undef)
43 (void)SvREFCNT_inc(sv);
45 key = AvARRAY(av) - AvALLOC(av);
47 AvALLOC(av)[--key] = &PL_sv_undef;
55 Pre-extend an array. The C<key> is the index to which the array should be
62 Perl_av_extend(pTHX_ AV *av, I32 key)
65 if ((mg = SvTIED_mg((SV*)av, PERL_MAGIC_tied))) {
69 PUSHSTACKi(PERLSI_MAGIC);
72 PUSHs(SvTIED_obj((SV*)av, mg));
73 PUSHs(sv_2mortal(newSViv(key+1)));
75 call_method("EXTEND", G_SCALAR|G_DISCARD);
81 if (key > AvMAX(av)) {
86 if (AvALLOC(av) != AvARRAY(av)) {
87 ary = AvALLOC(av) + AvFILLp(av) + 1;
88 tmp = AvARRAY(av) - AvALLOC(av);
89 Move(AvARRAY(av), AvALLOC(av), AvFILLp(av)+1, SV*);
91 SvPVX(av) = (char*)AvALLOC(av);
94 ary[--tmp] = &PL_sv_undef;
97 if (key > AvMAX(av) - 10) {
98 newmax = key + AvMAX(av);
103 #ifdef PERL_MALLOC_WRAP
104 static const char oom_array_extend[] =
105 "Out of memory during array extend"; /* Duplicated in pp_hot.c */
109 #if !defined(STRANGE_MALLOC) && !defined(MYMALLOC)
115 newmax = malloced_size((void*)AvALLOC(av))/sizeof(SV*) - 1;
120 newmax = key + AvMAX(av) / 5;
122 MEM_WRAP_CHECK_1(newmax+1, SV*, oom_array_extend);
123 #if defined(STRANGE_MALLOC) || defined(MYMALLOC)
124 Renew(AvALLOC(av),newmax+1, SV*);
126 bytes = (newmax + 1) * sizeof(SV*);
127 #define MALLOC_OVERHEAD 16
128 itmp = MALLOC_OVERHEAD;
129 while ((MEM_SIZE)(itmp - MALLOC_OVERHEAD) < bytes)
131 itmp -= MALLOC_OVERHEAD;
133 assert(itmp > newmax);
135 assert(newmax >= AvMAX(av));
136 New(2,ary, newmax+1, SV*);
137 Copy(AvALLOC(av), ary, AvMAX(av)+1, SV*);
139 offer_nice_chunk(AvALLOC(av), (AvMAX(av)+1) * sizeof(SV*));
141 Safefree(AvALLOC(av));
147 ary = AvALLOC(av) + AvMAX(av) + 1;
148 tmp = newmax - AvMAX(av);
149 if (av == PL_curstack) { /* Oops, grew stack (via av_store()?) */
150 PL_stack_sp = AvALLOC(av) + (PL_stack_sp - PL_stack_base);
151 PL_stack_base = AvALLOC(av);
152 PL_stack_max = PL_stack_base + newmax;
156 newmax = key < 3 ? 3 : key;
157 MEM_WRAP_CHECK_1(newmax+1, SV*, oom_array_extend);
158 New(2,AvALLOC(av), newmax+1, SV*);
159 ary = AvALLOC(av) + 1;
161 AvALLOC(av)[0] = &PL_sv_undef; /* For the stacks */
165 ary[--tmp] = &PL_sv_undef;
168 SvPVX(av) = (char*)AvALLOC(av);
177 Returns the SV at the specified index in the array. The C<key> is the
178 index. If C<lval> is set then the fetch will be part of a store. Check
179 that the return value is non-null before dereferencing it to a C<SV*>.
181 See L<perlguts/"Understanding the Magic of Tied Hashes and Arrays"> for
182 more information on how to use this function on tied arrays.
188 Perl_av_fetch(pTHX_ register AV *av, I32 key, I32 lval)
195 if (SvRMAGICAL(av)) {
196 MAGIC *tied_magic = mg_find((SV*)av, PERL_MAGIC_tied);
197 if (tied_magic || mg_find((SV*)av, PERL_MAGIC_regdata)) {
198 U32 adjust_index = 1;
200 if (tied_magic && key < 0) {
201 /* Handle negative array indices 20020222 MJD */
202 SV **negative_indices_glob =
203 hv_fetch(SvSTASH(SvRV(SvTIED_obj((SV *)av,
205 NEGATIVE_INDICES_VAR, 16, 0);
207 if (negative_indices_glob
208 && SvTRUE(GvSV(*negative_indices_glob)))
212 if (key < 0 && adjust_index) {
213 key += AvFILL(av) + 1;
219 sv_upgrade(sv, SVt_PVLV);
220 mg_copy((SV*)av, sv, 0, key);
222 LvTARG(sv) = sv; /* fake (SV**) */
223 return &(LvTARG(sv));
228 key += AvFILL(av) + 1;
233 if (key > AvFILLp(av)) {
237 return av_store(av,key,sv);
239 if (AvARRAY(av)[key] == &PL_sv_undef) {
243 return av_store(av,key,sv);
248 && (!AvARRAY(av)[key] /* eg. @_ could have freed elts */
249 || SvTYPE(AvARRAY(av)[key]) == SVTYPEMASK)) {
250 AvARRAY(av)[key] = &PL_sv_undef; /* 1/2 reify */
253 return &AvARRAY(av)[key];
259 Stores an SV in an array. The array index is specified as C<key>. The
260 return value will be NULL if the operation failed or if the value did not
261 need to be actually stored within the array (as in the case of tied
262 arrays). Otherwise it can be dereferenced to get the original C<SV*>. Note
263 that the caller is responsible for suitably incrementing the reference
264 count of C<val> before the call, and decrementing it if the function
267 See L<perlguts/"Understanding the Magic of Tied Hashes and Arrays"> for
268 more information on how to use this function on tied arrays.
274 Perl_av_store(pTHX_ register AV *av, I32 key, SV *val)
283 if (SvRMAGICAL(av)) {
284 MAGIC *tied_magic = mg_find((SV*)av, PERL_MAGIC_tied);
286 /* Handle negative array indices 20020222 MJD */
288 unsigned adjust_index = 1;
289 SV **negative_indices_glob =
290 hv_fetch(SvSTASH(SvRV(SvTIED_obj((SV *)av,
292 NEGATIVE_INDICES_VAR, 16, 0);
293 if (negative_indices_glob
294 && SvTRUE(GvSV(*negative_indices_glob)))
297 key += AvFILL(av) + 1;
302 if (val != &PL_sv_undef) {
303 mg_copy((SV*)av, val, 0, key);
311 key += AvFILL(av) + 1;
316 if (SvREADONLY(av) && key >= AvFILL(av))
317 Perl_croak(aTHX_ PL_no_modify);
319 if (!AvREAL(av) && AvREIFY(av))
324 if (AvFILLp(av) < key) {
326 if (av == PL_curstack && key > PL_stack_sp - PL_stack_base)
327 PL_stack_sp = PL_stack_base + key; /* XPUSH in disguise */
329 ary[++AvFILLp(av)] = &PL_sv_undef;
330 while (AvFILLp(av) < key);
335 SvREFCNT_dec(ary[key]);
337 if (SvSMAGICAL(av)) {
338 if (val != &PL_sv_undef) {
339 MAGIC* mg = SvMAGIC(av);
340 sv_magic(val, (SV*)av, toLOWER(mg->mg_type), 0, key);
350 Creates a new AV. The reference count is set to 1.
360 av = (AV*)NEWSV(3,0);
361 sv_upgrade((SV *)av, SVt_PVAV);
365 AvMAX(av) = AvFILLp(av) = -1;
372 Creates a new AV and populates it with a list of SVs. The SVs are copied
373 into the array, so they may be freed after the call to av_make. The new AV
374 will have a reference count of 1.
380 Perl_av_make(pTHX_ register I32 size, register SV **strp)
386 av = (AV*)NEWSV(8,0);
387 sv_upgrade((SV *) av,SVt_PVAV);
388 AvFLAGS(av) = AVf_REAL;
389 if (size) { /* `defined' was returning undef for size==0 anyway. */
392 SvPVX(av) = (char*)ary;
393 AvFILLp(av) = size - 1;
394 AvMAX(av) = size - 1;
395 for (i = 0; i < size; i++) {
398 sv_setsv(ary[i], *strp);
406 Perl_av_fake(pTHX_ register I32 size, register SV **strp)
411 av = (AV*)NEWSV(9,0);
412 sv_upgrade((SV *)av, SVt_PVAV);
413 New(4,ary,size+1,SV*);
415 Copy(strp,ary,size,SV*);
416 AvFLAGS(av) = AVf_REIFY;
417 SvPVX(av) = (char*)ary;
418 AvFILLp(av) = size - 1;
419 AvMAX(av) = size - 1;
431 Clears an array, making it empty. Does not free the memory used by the
438 Perl_av_clear(pTHX_ register AV *av)
444 if (SvREFCNT(av) == 0 && ckWARN_d(WARN_DEBUGGING)) {
445 Perl_warner(aTHX_ packWARN(WARN_DEBUGGING), "Attempt to clear deleted array");
453 Perl_croak(aTHX_ PL_no_modify);
455 /* Give any tie a chance to cleanup first */
464 key = AvFILLp(av) + 1;
466 SV * sv = ary[--key];
467 /* undef the slot before freeing the value, because a
468 * destructor might try to modify this arrray */
469 ary[key] = &PL_sv_undef;
473 if ((key = AvARRAY(av) - AvALLOC(av))) {
475 SvPVX(av) = (char*)AvALLOC(av);
484 Undefines the array. Frees the memory used by the array itself.
490 Perl_av_undef(pTHX_ register AV *av)
498 /* Give any tie a chance to cleanup first */
499 if (SvTIED_mg((SV*)av, PERL_MAGIC_tied))
500 av_fill(av, -1); /* mg_clear() ? */
503 key = AvFILLp(av) + 1;
505 SvREFCNT_dec(AvARRAY(av)[--key]);
507 Safefree(AvALLOC(av));
510 AvMAX(av) = AvFILLp(av) = -1;
512 SvREFCNT_dec(AvARYLEN(av));
520 Pushes an SV onto the end of the array. The array will grow automatically
521 to accommodate the addition.
527 Perl_av_push(pTHX_ register AV *av, SV *val)
533 Perl_croak(aTHX_ PL_no_modify);
535 if ((mg = SvTIED_mg((SV*)av, PERL_MAGIC_tied))) {
537 PUSHSTACKi(PERLSI_MAGIC);
540 PUSHs(SvTIED_obj((SV*)av, mg));
544 call_method("PUSH", G_SCALAR|G_DISCARD);
549 av_store(av,AvFILLp(av)+1,val);
555 Pops an SV off the end of the array. Returns C<&PL_sv_undef> if the array
562 Perl_av_pop(pTHX_ register AV *av)
570 Perl_croak(aTHX_ PL_no_modify);
571 if ((mg = SvTIED_mg((SV*)av, PERL_MAGIC_tied))) {
573 PUSHSTACKi(PERLSI_MAGIC);
575 XPUSHs(SvTIED_obj((SV*)av, mg));
578 if (call_method("POP", G_SCALAR)) {
579 retval = newSVsv(*PL_stack_sp--);
581 retval = &PL_sv_undef;
589 retval = AvARRAY(av)[AvFILLp(av)];
590 AvARRAY(av)[AvFILLp(av)--] = &PL_sv_undef;
597 =for apidoc av_unshift
599 Unshift the given number of C<undef> values onto the beginning of the
600 array. The array will grow automatically to accommodate the addition. You
601 must then use C<av_store> to assign values to these new elements.
607 Perl_av_unshift(pTHX_ register AV *av, register I32 num)
617 Perl_croak(aTHX_ PL_no_modify);
619 if ((mg = SvTIED_mg((SV*)av, PERL_MAGIC_tied))) {
621 PUSHSTACKi(PERLSI_MAGIC);
624 PUSHs(SvTIED_obj((SV*)av, mg));
630 call_method("UNSHIFT", G_SCALAR|G_DISCARD);
638 if (!AvREAL(av) && AvREIFY(av))
640 i = AvARRAY(av) - AvALLOC(av);
648 SvPVX(av) = (char*)(AvARRAY(av) - i);
652 /* Create extra elements */
653 slide = i > 0 ? i : 0;
655 av_extend(av, i + num);
658 Move(ary, ary + num, i + 1, SV*);
660 ary[--num] = &PL_sv_undef;
662 /* Make extra elements into a buffer */
664 AvFILLp(av) -= slide;
665 SvPVX(av) = (char*)(AvARRAY(av) + slide);
672 Shifts an SV off the beginning of the array.
678 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 SvPVX(av) = (char*)(AvARRAY(av) + 1);
719 Returns the highest index in the array. Returns -1 if the array is
726 Perl_av_len(pTHX_ 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)
744 Perl_croak(aTHX_ "panic: null array");
747 if ((mg = SvTIED_mg((SV*)av, PERL_MAGIC_tied))) {
751 PUSHSTACKi(PERLSI_MAGIC);
754 PUSHs(SvTIED_obj((SV*)av, mg));
755 PUSHs(sv_2mortal(newSViv(fill+1)));
757 call_method("STORESIZE", G_SCALAR|G_DISCARD);
763 if (fill <= AvMAX(av)) {
764 I32 key = AvFILLp(av);
765 SV** ary = AvARRAY(av);
769 SvREFCNT_dec(ary[key]);
770 ary[key--] = &PL_sv_undef;
775 ary[++key] = &PL_sv_undef;
783 (void)av_store(av,fill,&PL_sv_undef);
787 =for apidoc av_delete
789 Deletes the element indexed by C<key> from the array. Returns the
790 deleted element. If C<flags> equals C<G_DISCARD>, the element is freed
791 and null is returned.
796 Perl_av_delete(pTHX_ AV *av, I32 key, I32 flags)
803 Perl_croak(aTHX_ PL_no_modify);
805 if (SvRMAGICAL(av)) {
806 MAGIC *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 */
811 unsigned adjust_index = 1;
813 SV **negative_indices_glob =
814 hv_fetch(SvSTASH(SvRV(SvTIED_obj((SV *)av,
816 NEGATIVE_INDICES_VAR, 16, 0);
817 if (negative_indices_glob
818 && SvTRUE(GvSV(*negative_indices_glob)))
822 key += AvFILL(av) + 1;
827 svp = av_fetch(av, key, TRUE);
831 if (mg_find(sv, PERL_MAGIC_tiedelem)) {
832 sv_unmagic(sv, PERL_MAGIC_tiedelem); /* No longer an element */
841 key += AvFILL(av) + 1;
846 if (key > AvFILLp(av))
849 if (!AvREAL(av) && AvREIFY(av))
851 sv = AvARRAY(av)[key];
852 if (key == AvFILLp(av)) {
853 AvARRAY(av)[key] = &PL_sv_undef;
856 } while (--key >= 0 && AvARRAY(av)[key] == &PL_sv_undef);
859 AvARRAY(av)[key] = &PL_sv_undef;
863 if (flags & G_DISCARD) {
873 =for apidoc av_exists
875 Returns true if the element indexed by C<key> has been initialized.
877 This relies on the fact that uninitialized array elements are set to
883 Perl_av_exists(pTHX_ AV *av, I32 key)
889 if (SvRMAGICAL(av)) {
890 MAGIC *tied_magic = mg_find((SV*)av, PERL_MAGIC_tied);
891 if (tied_magic || mg_find((SV*)av, PERL_MAGIC_regdata)) {
892 SV *sv = sv_newmortal();
894 /* Handle negative array indices 20020222 MJD */
896 unsigned adjust_index = 1;
898 SV **negative_indices_glob =
899 hv_fetch(SvSTASH(SvRV(SvTIED_obj((SV *)av,
901 NEGATIVE_INDICES_VAR, 16, 0);
902 if (negative_indices_glob
903 && SvTRUE(GvSV(*negative_indices_glob)))
907 key += AvFILL(av) + 1;
913 mg_copy((SV*)av, sv, 0, key);
914 mg = mg_find(sv, PERL_MAGIC_tiedelem);
916 magic_existspack(sv, mg);
917 return (bool)SvTRUE(sv);
924 key += AvFILL(av) + 1;
929 if (key <= AvFILLp(av) && AvARRAY(av)[key] != &PL_sv_undef