xref: /onnv-gate/usr/src/cmd/perl/5.8.4/distrib/av.h (revision 0:68f95e015346)
1 /*    av.h
2  *
3  *    Copyright (C) 1991, 1992, 1993, 1995, 1996, 1997, 1998, 1999,
4  *    2000, 2001, 2002, by Larry Wall and others
5  *
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.
8  *
9  */
10 
11 struct xpvav {
12     char*	xav_array;      /* pointer to first array element */
13     SSize_t	xav_fill;       /* Index of last element present */
14     SSize_t	xav_max;        /* max index for which array has space */
15     IV		xof_off;	/* ptr is incremented by offset */
16     NV		xnv_nv;		/* numeric value, if any */
17     MAGIC*	xmg_magic;	/* magic for scalar array */
18     HV*		xmg_stash;	/* class package */
19 
20     SV**	xav_alloc;	/* pointer to beginning of C array of SVs */
21     SV*		xav_arylen;
22     U8		xav_flags;
23 };
24 
25 
26 /* AVf_REAL is set for all AVs whose xav_array contents are refcounted.
27  * Some things like "@_" and the scratchpad list do not set this, to
28  * indicate that they are cheating (for efficiency) by not refcounting
29  * the AV's contents.
30  *
31  * AVf_REIFY is only meaningful on such "fake" AVs (i.e. where AVf_REAL
32  * is not set).  It indicates that the fake AV is capable of becoming
33  * real if the array needs to be modified in some way.  Functions that
34  * modify fake AVs check both flags to call av_reify() as appropriate.
35  *
36  * Note that the Perl stack and @DB::args have neither flag set. (Thus,
37  * items that go on the stack are never refcounted.)
38  *
39  * These internal details are subject to change any time.  AV
40  * manipulations external to perl should not care about any of this.
41  * GSAR 1999-09-10
42  */
43 #define AVf_REAL 1	/* free old entries */
44 #define AVf_REIFY 2	/* can become real */
45 
46 /* XXX this is not used anywhere */
47 #define AVf_REUSED 4	/* got undeffed--don't turn old memory into SVs now */
48 
49 /*
50 =head1 Handy Values
51 
52 =for apidoc AmU||Nullav
53 Null AV pointer.
54 
55 =head1 Array Manipulation Functions
56 
57 =for apidoc Am|int|AvFILL|AV* av
58 Same as C<av_len()>.  Deprecated, use C<av_len()> instead.
59 
60 =cut
61 */
62 
63 #define Nullav Null(AV*)
64 
65 #define AvARRAY(av)	((SV**)((XPVAV*)  SvANY(av))->xav_array)
66 #define AvALLOC(av)	((XPVAV*)  SvANY(av))->xav_alloc
67 #define AvMAX(av)	((XPVAV*)  SvANY(av))->xav_max
68 #define AvFILLp(av)	((XPVAV*)  SvANY(av))->xav_fill
69 #define AvARYLEN(av)	((XPVAV*)  SvANY(av))->xav_arylen
70 #define AvFLAGS(av)	((XPVAV*)  SvANY(av))->xav_flags
71 
72 #define AvREAL(av)	(AvFLAGS(av) & AVf_REAL)
73 #define AvREAL_on(av)	(AvFLAGS(av) |= AVf_REAL)
74 #define AvREAL_off(av)	(AvFLAGS(av) &= ~AVf_REAL)
75 #define AvREIFY(av)	(AvFLAGS(av) & AVf_REIFY)
76 #define AvREIFY_on(av)	(AvFLAGS(av) |= AVf_REIFY)
77 #define AvREIFY_off(av)	(AvFLAGS(av) &= ~AVf_REIFY)
78 #define AvREUSED(av)	(AvFLAGS(av) & AVf_REUSED)
79 #define AvREUSED_on(av)	(AvFLAGS(av) |= AVf_REUSED)
80 #define AvREUSED_off(av) (AvFLAGS(av) &= ~AVf_REUSED)
81 
82 #define AvREALISH(av)	(AvFLAGS(av) & (AVf_REAL|AVf_REIFY))
83 
84 #define AvFILL(av)	((SvRMAGICAL((SV *) (av))) \
85 			  ? mg_size((SV *) av) : AvFILLp(av))
86 
87 #define NEGATIVE_INDICES_VAR "NEGATIVE_INDICES"
88