/*????av.c
?*
?*????Copyright?（C）?1991?1992?1993?1994?1995?1996?1997?1998?1999?2000
?*????2001?2002?2003?2004?2005?2006?2007?2008?by?Larry?Wall?and?others
?*
?*????You?may?distribute?under?the?terms?of?either?the?GNU?General?Public
?*????License?or?the?Artistic?License?as?specified?in?the?README?file.
?*
?*/

/*
?*?‘...for?the?Entwives?desired?order?and?plenty?and?peace?（by?which?they
?*??meant?that?things?should?remain?where?they?had?set?them）.‘?--Treebeard
?*
?*?????[p.476?of?_The?Lord?of?the?Rings_?III/iv:?“Treebeard“]
?*/

/*
=head1?Array?Manipulation?Functions
*/

#include?“EXTERN.h“
#define?PERL_IN_AV_C
#include?“perl.h“

void
Perl_av_reify（pTHX_?AV?*av）
{
????SSize_t?key;

????PERL_ARGS_ASSERT_AV_REIFY;
????assert（SvTYPE（av）?==?SVt_PVAV）;

????if?（AvREAL（av））
	return;
#ifdef?DEBUGGING
????if?（SvTIED_mg（（const?SV?*）av?PERL_MAGIC_tied））
	Perl_ck_warner_d（aTHX_?packWARN（WARN_DEBUGGING）?“av_reify?called?on?tied?array“）;
#endif
????key?=?AvMAX（av）?+?1;
????while?（key?>?AvFILLp（av）?+?1）
	AvARRAY（av）[--key]?=?NULL;
????while?（key）?{
	SV?*?const?sv?=?AvARRAY（av）[--key];
	if?（sv?!=?&PL_sv_undef）
	????SvREFCNT_inc_simple_void（sv）;
????}
????key?=?AvARRAY（av）?-?AvALLOC（av）;
????while?（key）
	AvALLOC（av）[--key]?=?NULL;
????AvREIFY_off（av）;
????AvREAL_on（av）;
}

/*
=for?apidoc?av_extend

Pre-extend?an?array.??The?C?is?the?index?to?which?the?array?should?be
extended.

=cut
*/

void
Perl_av_extend（pTHX_?AV?*av?SSize_t?key）
{
????MAGIC?*mg;

????PERL_ARGS_ASSERT_AV_EXTEND;
????assert（SvTYPE（av）?==?SVt_PVAV）;

????mg?=?SvTIED_mg（（const?SV?*）av?PERL_MAGIC_tied）;
????if?（mg）?{
	SV?*arg1?=?sv_newmortal（）;
	sv_setiv（arg1?（IV）（key?+?1））;
	Perl_magic_methcall（aTHX_?MUTABLE_SV（av）?mg?SV_CONST（EXTEND）?G_DISCARD?1
			????arg1）;
	return;
????}
????av_extend_guts（avkey&AvMAX（av）&AvALLOC（av）&AvARRAY（av））;
}????

/*?The?guts?of?av_extend.??*Not*?for?general?use!?*/
void
Perl_av_extend_guts（pTHX_?AV?*av?SSize_t?key?SSize_t?*maxp?SV?***allocp
			??SV?***arrayp）
{
????PERL_ARGS_ASSERT_AV_EXTEND_GUTS;

????if?（key?????????Perl_croak（aTHX_
????????????“panic:?av_extend_guts（）?negative?count?（%“IVdf“）“?（IV）key）;

????if?（key?>?*maxp）?{
	SV**?ary;
	SSize_t?tmp;
	SSize_t?newmax;

	if?（av?&&?*allocp?!=?*arrayp）?{
	????ary?=?*allocp?+?AvFILLp（av）?+?1;
	????tmp?=?*arrayp?-?*allocp;
	????Move（*arrayp?*allocp?AvFILLp（av）+1?SV*）;
	????*maxp?+=?tmp;
	????*arrayp?=?*allocp;
	????if?（AvREAL（av））?{
		while?（tmp）
		????ary[--tmp]?=?NULL;
	????}
	????if?（key?>?*maxp?-?10）?{
		newmax?=?key?+?*maxp;
		goto?resize;
	????}
	}
	else?{
	????if?（*allocp）?{

#ifdef?Perl_safesysmalloc_size
		/*?Whilst?it?would?be?quite?possible?to?move?this?logic?around
		???（as?I?did?in?the?SV?code）?so?as?to?set?AvMAX（av）?early
		???based?on?calling?Perl_safesysmalloc_size（）?immediately?after
		???allocation?I‘m?not?convinced?that?it?is?a?great?idea?here.
		???In?an?array?we?have?to?loop?round?setting?everything?to
		???NULL?which?means?wr