3 * Copyright (C) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
4 * 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009 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 #undef sv_flags /* Convex has this in <signal.h> for sigvec() */
16 =for apidoc_section $SV_flags
18 =for apidoc Ay||svtype
19 An enum of flags for Perl types. These are found in the file F<sv.h>
20 in the C<svtype> enum. Test these flags with the C<SvTYPE> macro.
42 These are most easily explained from the bottom up.
44 C<SVt_PVIO> is for I/O objects, C<SVt_PVFM> for formats, C<SVt_PVCV> for
45 subroutines, C<SVt_PVHV> for hashes and C<SVt_PVAV> for arrays.
47 All the others are scalar types, that is, things that can be bound to a
48 C<$> variable. For these, the internal types are mostly orthogonal to
49 types in the Perl language.
51 Hence, checking C<< SvTYPE(sv) < SVt_PVAV >> is the best way to see whether
52 something is a scalar.
54 C<SVt_PVGV> represents a typeglob. If C<!SvFAKE(sv)>, then it is a real,
55 incoercible typeglob. If C<SvFAKE(sv)>, then it is a scalar to which a
56 typeglob has been assigned. Assigning to it again will stop it from being
57 a typeglob. C<SVt_PVLV> represents a scalar that delegates to another scalar
58 behind the scenes. It is used, e.g., for the return value of C<substr> and
59 for tied hash and array elements. It can hold any scalar value, including
60 a typeglob. C<SVt_REGEXP> is for regular
61 expressions. C<SVt_INVLIST> is for Perl
62 core internal use only.
64 C<SVt_PVMG> represents a "normal" scalar (not a typeglob, regular expression,
65 or delegate). Since most scalars do not need all the internal fields of a
66 PVMG, we save memory by allocating smaller structs when possible. All the
67 other types are just simpler forms of C<SVt_PVMG>, with fewer internal fields.
68 C<SVt_NULL> can only hold undef. C<SVt_IV> can hold undef, an integer, or a
69 reference. (C<SVt_RV> is an alias for C<SVt_IV>, which exists for backward
70 compatibility.) C<SVt_NV> can hold any of those or a double. C<SVt_PV> can only
71 hold C<undef> or a string. C<SVt_PVIV> is a superset of C<SVt_PV> and C<SVt_IV>.
72 C<SVt_PVNV> is similar. C<SVt_PVMG> can hold anything C<SVt_PVNV> can hold, but it
73 can, but does not have to, be blessed or magical.
75 =for apidoc AmnU||SVt_NULL
76 Type flag for scalars. See L</svtype>.
78 =for apidoc AmnU||SVt_IV
79 Type flag for scalars. See L</svtype>.
81 =for apidoc AmnU||SVt_NV
82 Type flag for scalars. See L</svtype>.
84 =for apidoc AmnU||SVt_PV
85 Type flag for scalars. See L</svtype>.
87 =for apidoc AmnU||SVt_PVIV
88 Type flag for scalars. See L</svtype>.
90 =for apidoc AmnU||SVt_PVNV
91 Type flag for scalars. See L</svtype>.
93 =for apidoc AmnU||SVt_PVMG
94 Type flag for scalars. See L</svtype>.
96 =for apidoc CmnU||SVt_INVLIST
97 Type flag for scalars. See L<perlapi/svtype>.
99 =for apidoc AmnU||SVt_REGEXP
100 Type flag for regular expressions. See L</svtype>.
102 =for apidoc AmnU||SVt_PVGV
103 Type flag for typeglobs. See L</svtype>.
105 =for apidoc AmnU||SVt_PVLV
106 Type flag for scalars. See L</svtype>.
108 =for apidoc AmnU||SVt_PVAV
109 Type flag for arrays. See L</svtype>.
111 =for apidoc AmnU||SVt_PVHV
112 Type flag for hashes. See L</svtype>.
114 =for apidoc AmnU||SVt_PVCV
115 Type flag for subroutines. See L</svtype>.
117 =for apidoc AmnU||SVt_PVFM
118 Type flag for formats. See L</svtype>.
120 =for apidoc AmnU||SVt_PVIO
121 Type flag for I/O objects. See L</svtype>.
125 These are ordered so that the simpler types have a lower value; SvUPGRADE
126 doesn't allow you to upgrade from a higher numbered type to a lower numbered
127 one; also there is code that assumes that anything that has as a PV component
128 has a type numbered >= SVt_PV.
134 /* BIND was here, before INVLIST replaced it. */
137 /* RV was here, before it was merged with IV. */
139 SVt_INVLIST, /* 4, implemented as a PV */
144 /* PVBM was here, before BIND replaced it. */
152 /* 16-31: Unused, though one should be reserved for a
153 * freed sv, if the other 3 bits below the flags ones
155 SVt_LAST /* keep last in enum. used to size arrays */
158 /* *** any alterations to the SV types above need to be reflected in
159 * SVt_MASK and the various PL_valid_types_* tables. As of this writing those
160 * tables are in perl.h. There are also two affected names tables in dump.c,
161 * one in B.xs, and 'bodies_by_type[]' in sv.c.
163 * The bits that match 0xe0 are CURRENTLY UNUSED
164 * The bits above that are for flags, like SVf_IOK */
166 #define SVt_MASK 0x1f /* smallest bitmask that covers all types */
169 /* Fast Boyer Moore tables are now stored in magic attached to PVMGs */
170 # define SVt_PVBM SVt_PVMG
171 /* Anything wanting to create a reference from clean should ensure that it has
172 a scalar of type SVt_IV now: */
173 # define SVt_RV SVt_IV
176 /* The array of arena roots for SV bodies is indexed by SvTYPE. SVt_NULL doesn't
177 * use a body, so that arena root is re-used for HEs. SVt_IV also doesn't, so
178 * that arena root is used for HVs with struct xpvhv_aux. */
179 #if defined(PERL_IN_HV_C) || defined(PERL_IN_XS_APITEST)
180 # define HE_ARENA_ROOT_IX SVt_NULL
182 #if defined(PERL_IN_HV_C) || defined(PERL_IN_SV_C)
183 # define HVAUX_ARENA_ROOT_IX SVt_IV
186 # define SVt_FIRST SVt_NULL /* the type of SV that new_SV() in sv.c returns */
189 #define PERL_ARENA_ROOTS_SIZE (SVt_LAST)
191 /* typedefs to eliminate some typing */
192 typedef struct he HE;
193 typedef struct hek HEK;
195 /* Using C's structural equivalence to help emulate C++ inheritance here... */
197 /* start with 2 sv-head building blocks */
198 #define _SV_HEAD(ptrtype) \
199 ptrtype sv_any; /* pointer to body */ \
200 U32 sv_refcnt; /* how many references to us */ \
201 U32 sv_flags /* what we are */
204 # define _NV_BODYLESS_UNION NV svu_nv;
206 # define _NV_BODYLESS_UNION
209 #define _SV_HEAD_UNION \
211 char* svu_pv; /* pointer to malloced string */ \
215 SV* svu_rv; /* pointer to another SV */ \
223 #ifdef DEBUG_LEAKING_SCALARS
224 #define _SV_HEAD_DEBUG ;\
225 PERL_BITFIELD32 sv_debug_optype:9; /* the type of OP that allocated us */ \
226 PERL_BITFIELD32 sv_debug_inpad:1; /* was allocated in a pad for an OP */ \
227 PERL_BITFIELD32 sv_debug_line:16; /* the line where we were allocated */ \
228 UV sv_debug_serial; /* serial number of sv allocation */ \
229 char * sv_debug_file; /* the file where we were allocated */ \
230 SV * sv_debug_parent /* what we were cloned from (ithreads)*/
232 #define _SV_HEAD_DEBUG
235 struct STRUCT_SV { /* struct sv { */
241 _SV_HEAD(XPVGV*); /* pointer to xpvgv body */
246 _SV_HEAD(XPVCV*); /* pointer to xpvcv body */
251 _SV_HEAD(XPVAV*); /* pointer to xpvav body */
256 _SV_HEAD(XPVHV*); /* pointer to xpvhv body */
261 _SV_HEAD(XPVIO*); /* pointer to xpvio body */
266 _SV_HEAD(struct regexp*); /* pointer to regexp body */
271 _SV_HEAD(XINVLIST*); /* pointer to xpvinvlist body */
276 #undef _SV_HEAD_UNION /* ensure no pollution */
279 =for apidoc_section $SV
281 =for apidoc Am|U32|SvREFCNT|SV* sv
282 Returns the value of the object's reference count. Exposed
283 to perl code via Internals::SvREFCNT().
285 =for apidoc SvREFCNT_inc
286 =for apidoc_item SvREFCNT_inc_NN
287 =for apidoc_item SvREFCNT_inc_void
288 =for apidoc_item |void|SvREFCNT_inc_void_NN|SV* sv
289 =for apidoc_item |SV*|SvREFCNT_inc_simple|SV* sv
290 =for apidoc_item |SV*|SvREFCNT_inc_simple_NN|SV* sv
291 =for apidoc_item |void|SvREFCNT_inc_simple_void|SV* sv
292 =for apidoc_item |void|SvREFCNT_inc_simple_void_NN|SV* sv
294 These all increment the reference count of the given SV.
295 The ones without C<void> in their names return the SV.
297 C<SvREFCNT_inc> is the base operation; the rest are optimizations if various
298 input constraints are known to be true; hence, all can be replaced with
301 C<SvREFCNT_inc_NN> can only be used if you know C<sv> is not C<NULL>. Since we
302 don't have to check the NULLness, it's faster and smaller.
304 C<SvREFCNT_inc_void> can only be used if you don't need the
305 return value. The macro doesn't need to return a meaningful value.
307 C<SvREFCNT_inc_void_NN> can only be used if you both don't need the return
308 value, and you know that C<sv> is not C<NULL>. The macro doesn't need to
309 return a meaningful value, or check for NULLness, so it's smaller and faster.
311 C<SvREFCNT_inc_simple> can only be used with expressions without side
312 effects. Since we don't have to store a temporary value, it's faster.
314 C<SvREFCNT_inc_simple_NN> can only be used with expressions without side
315 effects and you know C<sv> is not C<NULL>. Since we don't have to store a
316 temporary value, nor check for NULLness, it's faster and smaller.
318 C<SvREFCNT_inc_simple_void> can only be used with expressions without side
319 effects and you don't need the return value.
321 C<SvREFCNT_inc_simple_void_NN> can only be used with expressions without side
322 effects, you don't need the return value, and you know C<sv> is not C<NULL>.
324 =for apidoc SvREFCNT_dec
325 =for apidoc_item SvREFCNT_dec_NN
327 These decrement the reference count of the given SV.
329 C<SvREFCNT_dec_NN> may only be used when C<sv> is known to not be C<NULL>.
331 =for apidoc Am|svtype|SvTYPE|SV* sv
332 Returns the type of the SV. See C<L</svtype>>.
334 =for apidoc Am|void|SvUPGRADE|SV* sv|svtype type
335 Used to upgrade an SV to a more complex form. Uses C<sv_upgrade> to
336 perform the upgrade if necessary. See C<L</svtype>>.
341 #define SvANY(sv) (sv)->sv_any
342 #define SvFLAGS(sv) (sv)->sv_flags
343 #define SvREFCNT(sv) (sv)->sv_refcnt
345 #define SvREFCNT_inc(sv) Perl_SvREFCNT_inc(MUTABLE_SV(sv))
346 #define SvREFCNT_inc_simple(sv) SvREFCNT_inc(sv)
347 #define SvREFCNT_inc_NN(sv) Perl_SvREFCNT_inc_NN(MUTABLE_SV(sv))
348 #define SvREFCNT_inc_void(sv) Perl_SvREFCNT_inc_void(MUTABLE_SV(sv))
350 /* These guys don't need the curly blocks */
351 #define SvREFCNT_inc_simple_void(sv) STMT_START { if (sv) SvREFCNT(sv)++; } STMT_END
352 #define SvREFCNT_inc_simple_NN(sv) (++(SvREFCNT(sv)),MUTABLE_SV(sv))
353 #define SvREFCNT_inc_void_NN(sv) (void)(++SvREFCNT(MUTABLE_SV(sv)))
354 #define SvREFCNT_inc_simple_void_NN(sv) (void)(++SvREFCNT(MUTABLE_SV(sv)))
356 #define SvREFCNT_dec(sv) Perl_SvREFCNT_dec(aTHX_ MUTABLE_SV(sv))
357 #define SvREFCNT_dec_NN(sv) Perl_SvREFCNT_dec_NN(aTHX_ MUTABLE_SV(sv))
359 #define SVTYPEMASK 0xff
360 #define SvTYPE(sv) ((svtype)((sv)->sv_flags & SVTYPEMASK))
362 /* Sadly there are some parts of the core that have pointers to already-freed
363 SV heads, and rely on being able to tell that they are now free. So mark
364 them all by using a consistent macro. */
365 #define SvIS_FREED(sv) UNLIKELY(((sv)->sv_flags == SVTYPEMASK))
367 /* this is defined in this peculiar way to avoid compiler warnings.
368 * See the <20121213131428.GD1842@iabyn.com> thread in p5p */
369 #define SvUPGRADE(sv, mt) \
370 ((void)(SvTYPE(sv) >= (mt) || (sv_upgrade(sv, mt),1)))
372 #define SVf_IOK 0x00000100 /* has valid public integer value */
373 #define SVf_NOK 0x00000200 /* has valid public numeric value */
374 #define SVf_POK 0x00000400 /* has valid public pointer value */
375 #define SVf_ROK 0x00000800 /* has a valid reference pointer */
377 #define SVp_IOK 0x00001000 /* has valid non-public integer value */
378 #define SVp_NOK 0x00002000 /* has valid non-public numeric value */
379 #define SVp_POK 0x00004000 /* has valid non-public pointer value */
380 #define SVp_SCREAM 0x00008000 /* currently unused on plain scalars */
381 #define SVphv_CLONEABLE SVp_SCREAM /* PVHV (stashes) clone its objects */
382 #define SVpgv_GP SVp_SCREAM /* GV has a valid GP */
383 #define SVprv_PCS_IMPORTED SVp_SCREAM /* RV is a proxy for a constant
384 subroutine in another package. Set the
385 GvIMPORTED_CV_on() if it needs to be
386 expanded to a real GV */
388 /* SVf_PROTECT is what SVf_READONLY should have been: i.e. modifying
389 * this SV is completely illegal. However, SVf_READONLY (via
390 * Internals::SvREADONLY()) has come to be seen as a flag that can be
391 * temporarily set and unset by the user to indicate e.g. whether a hash
392 * is "locked". Now, Hash::Util et al only set SVf_READONLY, while core
393 * sets both (SVf_READONLY|SVf_PROTECT) to indicate both to core and user
394 * code that this SV should not be messed with.
396 #define SVf_PROTECT 0x00010000 /* very read-only */
397 #define SVs_PADTMP 0x00020000 /* in use as tmp */
398 #define SVs_PADSTALE 0x00040000 /* lexical has gone out of scope;
399 only used when !PADTMP */
400 #define SVs_TEMP 0x00080000 /* mortal (implies string is stealable) */
401 #define SVs_OBJECT 0x00100000 /* is "blessed" */
402 #define SVs_GMG 0x00200000 /* has magical get method */
403 #define SVs_SMG 0x00400000 /* has magical set method */
404 #define SVs_RMG 0x00800000 /* has random magical methods */
406 #define SVf_FAKE 0x01000000 /* 0: glob is just a copy
407 1: SV head arena wasn't malloc()ed
408 2: For PVCV, whether CvUNIQUE(cv)
409 refers to an eval or once only
410 [CvEVAL(cv), CvSPECIAL(cv)]
411 3: HV: informally reserved by DAPM
413 4: Together with other flags (or
414 lack thereof) indicates a regex,
415 including PVLV-as-regex. See
418 #define SVf_OOK 0x02000000 /* has valid offset value. For a PVHV this
419 means that a hv_aux struct is present
420 after the main array */
421 #define SVf_BREAK 0x04000000 /* refcnt is artificially low - used by
422 SVs in final arena cleanup.
423 Set in S_regtry on PL_reg_curpm, so that
424 perl_destruct will skip it.
425 Used for mark and sweep by OP_AASSIGN
427 #define SVf_READONLY 0x08000000 /* may not be modified */
432 #define SVf_THINKFIRST (SVf_READONLY|SVf_PROTECT|SVf_ROK|SVf_FAKE \
435 #define SVf_OK (SVf_IOK|SVf_NOK|SVf_POK|SVf_ROK| \
436 SVp_IOK|SVp_NOK|SVp_POK|SVpgv_GP)
438 #define PRIVSHIFT 4 /* (SVp_?OK >> PRIVSHIFT) == SVf_?OK */
440 /* SVf_AMAGIC means that the stash *may* have overload methods. It's
441 * set each time a function is compiled into a stash, and is reset by the
442 * overload code when called for the first time and finds that there are
443 * no overload methods. Note that this used to be set on the object; but
444 * is now only set on stashes.
446 #define SVf_AMAGIC 0x10000000 /* has magical overloaded methods */
447 #define SVf_IsCOW 0x10000000 /* copy on write (shared hash key if
450 /* Ensure this value does not clash with the GV_ADD* flags in gv.h, or the
451 CV_CKPROTO_* flags in op.c, or the padadd_* flags in pad.h: */
452 #define SVf_UTF8 0x20000000 /* SvPV is UTF-8 encoded
453 This is also set on RVs whose overloaded
454 stringification is UTF-8. This might
455 only happen as a side effect of SvPV() */
457 #define SVphv_SHAREKEYS 0x20000000 /* PVHV keys live on shared string table */
459 /* PVAV could probably use 0x2000000 without conflict. I assume that PVFM can
460 be UTF-8 encoded, and PVCVs could well have UTF-8 prototypes. PVIOs haven't
461 been restructured, so sometimes get used as string buffers. */
464 /* Some private flags. */
467 /* scalar SVs with SVp_POK */
468 #define SVppv_STATIC 0x40000000 /* PV is pointer to static const; must be set with SVf_IsCOW */
470 #define SVpav_REAL 0x40000000 /* free old entries */
472 #define SVphv_LAZYDEL 0x40000000 /* entry in xhv_eiter must be deleted */
474 /* IV, PVIV, PVNV, PVMG, PVGV and (I assume) PVLV */
475 #define SVf_IVisUV 0x80000000 /* use XPVUV instead of XPVIV */
477 #define SVpav_REIFY 0x80000000 /* can become real */
479 #define SVphv_HASKFLAGS 0x80000000 /* keys have flag byte after hash */
480 /* RV upwards. However, SVf_ROK and SVp_IOK are exclusive */
481 #define SVprv_WEAKREF 0x80000000 /* Weak reference */
482 /* pad name vars only */
485 HV* xmg_stash; /* class package */ \
487 STRLEN xpv_cur; /* length of svu_pv as a C string */ \
489 STRLEN xpvlenu_len; /* allocated size */ \
490 struct regexp* xpvlenu_rx; /* regex when SV body is XPVLV */ \
493 #define xpv_len xpv_len_u.xpvlenu_len
496 NV xnv_nv; /* numeric value, if any */
498 line_t xnv_lines; /* used internally by S_scan_subst() */
499 bool xnv_bm_tail; /* an SvVALID (BM) SV has an implicit "\n" */
503 IV xivu_iv; /* integer value */
505 HEK * xivu_namehek; /* xpvlv, xpvgv: GvNAME */
506 bool xivu_eval_seen; /* used internally by S_scan_subst() */
511 MAGIC* xmg_magic; /* linked list of magicalness */
512 STRLEN xmg_hash_index; /* used while freeing hash entries */
524 #define xiv_iv xiv_u.xivu_iv
531 #define xuv_uv xuv_u.xivu_uv
539 /* This structure must match the beginning of struct xpvhv in hv.h. */
552 SSize_t xlvu_stargoff;
556 char xlv_type; /* k=keys .=pos x=substr v=vec /=join/re
557 * y=alem/helem/iter t=tie T=tied HE */
558 char xlv_flags; /* 1 = negative offset 2 = negative len
559 4 = out of range (vec) */
562 #define xlv_targoff xlv_targoff_u.xlvu_targoff
566 IV prev_index; /* caches result of previous invlist_search() */
567 STRLEN iterator; /* Stores where we are in iterating */
568 bool is_offset; /* The data structure for all inversion lists
569 begins with an element for code point U+0000.
570 If this bool is set, the actual list contains
571 that 0; otherwise, the list actually begins
572 with the following element. Thus to invert
573 the list, merely toggle this flag */
576 /* This structure works in 2 ways - regular scalar, or GV with GP */
584 typedef U32 cv_flags_t;
586 #define _XPVCV_COMMON \
594 void (*xcv_xsub) (pTHX_ CV*); \
602 PADLIST * xcv_padlist; \
606 U32 xcv_outside_seq; /* the COP sequence (at the point of our \
607 * compilation) in the lexically enclosing \
609 cv_flags_t xcv_flags; \
610 I32 xcv_depth /* >= 2 indicates recursive call */
612 /* This structure must match XPVCV in cv.h */
623 /* ifp and ofp are normally the same, but sockets need separate streams */
625 /* Cray addresses everything by word boundaries (64 bits) and
626 * code and data pointers cannot be mixed (which is exactly what
627 * Perl_filter_add() tries to do with the dirp), hence the
628 * following union trick (as suggested by Gurusamy Sarathy).
629 * For further information see Geir Johansen's problem report
630 * titled [ID 20000612.002 (#3366)] Perl problem on Cray system
631 * The any pointer (known as IoANY()) will also be a good place
632 * to hang any IO disciplines to.
635 DIR * xiou_dirp; /* for opendir, readdir, etc */
636 void * xiou_any; /* for alignment */
638 /* IV xio_lines is now in IVX $. */
639 IV xio_page; /* $% */
640 IV xio_page_len; /* $= */
641 IV xio_lines_left; /* $- */
642 char * xio_top_name; /* $^ */
643 GV * xio_top_gv; /* $^ */
644 char * xio_fmt_name; /* $~ */
645 GV * xio_fmt_gv; /* $~ */
646 char * xio_bottom_name;/* $^B */
647 GV * xio_bottom_gv; /* $^B */
652 #define xio_dirp xio_dirpu.xiou_dirp
653 #define xio_any xio_dirpu.xiou_any
655 #define IOf_ARGV 1 /* this fp iterates over ARGV */
656 #define IOf_START 2 /* check for null ARGV and substitute '-' */
657 #define IOf_FLUSH 4 /* this fp wants a flush after write op */
658 #define IOf_DIDTOP 8 /* just did top of form */
659 #define IOf_UNTAINT 16 /* consider this fp (and its data) "safe" */
660 #define IOf_NOLINE 32 /* slurped a pseudo-line from empty file */
661 #define IOf_FAKE_DIRP 64 /* xio_dirp is fake (source filters kludge)
662 Also, when this is set, SvPVX() is valid */
664 /* The following macros define implementation-independent predicates on SVs. */
667 =for apidoc Am|U32|SvNIOK|SV* sv
668 Returns a U32 value indicating whether the SV contains a number, integer or
671 =for apidoc Am|U32|SvNIOKp|SV* sv
672 Returns a U32 value indicating whether the SV contains a number, integer or
673 double. Checks the B<private> setting. Use C<SvNIOK> instead.
675 =for apidoc Am|void|SvNIOK_off|SV* sv
676 Unsets the NV/IV status of an SV.
678 =for apidoc Am|U32|SvOK|SV* sv
679 Returns a U32 value indicating whether the value is defined. This is
680 only meaningful for scalars.
682 =for apidoc Am|U32|SvIOKp|SV* sv
683 Returns a U32 value indicating whether the SV contains an integer. Checks
684 the B<private> setting. Use C<SvIOK> instead.
686 =for apidoc Am|U32|SvNOKp|SV* sv
687 Returns a U32 value indicating whether the SV contains a double. Checks the
688 B<private> setting. Use C<SvNOK> instead.
690 =for apidoc Am|U32|SvPOKp|SV* sv
691 Returns a U32 value indicating whether the SV contains a character string.
692 Checks the B<private> setting. Use C<SvPOK> instead.
694 =for apidoc Am|U32|SvIOK|SV* sv
695 Returns a U32 value indicating whether the SV contains an integer.
697 =for apidoc Am|void|SvIOK_on|SV* sv
698 Tells an SV that it is an integer.
700 =for apidoc Am|void|SvIOK_off|SV* sv
701 Unsets the IV status of an SV.
703 =for apidoc Am|void|SvIOK_only|SV* sv
704 Tells an SV that it is an integer and disables all other C<OK> bits.
706 =for apidoc Am|void|SvIOK_only_UV|SV* sv
707 Tells an SV that it is an unsigned integer and disables all other C<OK> bits.
709 =for apidoc Am|bool|SvIOK_UV|SV* sv
710 Returns a boolean indicating whether the SV contains an integer that must be
711 interpreted as unsigned. A non-negative integer whose value is within the
712 range of both an IV and a UV may be flagged as either C<SvUOK> or C<SvIOK>.
714 =for apidoc Am|bool|SvUOK|SV* sv
715 Returns a boolean indicating whether the SV contains an integer that must be
716 interpreted as unsigned. A non-negative integer whose value is within the
717 range of both an IV and a UV may be flagged as either C<SvUOK> or C<SvIOK>.
719 =for apidoc Am|bool|SvIOK_notUV|SV* sv
720 Returns a boolean indicating whether the SV contains a signed integer.
722 =for apidoc Am|U32|SvNOK|SV* sv
723 Returns a U32 value indicating whether the SV contains a double.
725 =for apidoc Am|void|SvNOK_on|SV* sv
726 Tells an SV that it is a double.
728 =for apidoc Am|void|SvNOK_off|SV* sv
729 Unsets the NV status of an SV.
731 =for apidoc Am|void|SvNOK_only|SV* sv
732 Tells an SV that it is a double and disables all other OK bits.
734 =for apidoc Am|U32|SvPOK|SV* sv
735 Returns a U32 value indicating whether the SV contains a character
738 =for apidoc Am|void|SvPOK_on|SV* sv
739 Tells an SV that it is a string.
741 =for apidoc Am|void|SvPOK_off|SV* sv
742 Unsets the PV status of an SV.
744 =for apidoc Am|void|SvPOK_only|SV* sv
745 Tells an SV that it is a string and disables all other C<OK> bits.
746 Will also turn off the UTF-8 status.
748 =for apidoc Am|bool|SvVOK|SV* sv
749 Returns a boolean indicating whether the SV contains a v-string.
751 =for apidoc Am|U32|SvOOK|SV* sv
752 Returns a U32 indicating whether the pointer to the string buffer is offset.
753 This hack is used internally to speed up removal of characters from the
754 beginning of a C<L</SvPV>>. When C<SvOOK> is true, then the start of the
755 allocated string buffer is actually C<SvOOK_offset()> bytes before C<SvPVX>.
756 This offset used to be stored in C<SvIVX>, but is now stored within the spare
759 =for apidoc Am|U32|SvROK|SV* sv
760 Tests if the SV is an RV.
762 =for apidoc Am|void|SvROK_on|SV* sv
763 Tells an SV that it is an RV.
765 =for apidoc Am|void|SvROK_off|SV* sv
766 Unsets the RV status of an SV.
768 =for apidoc Am|SV*|SvRV|SV* sv
769 Dereferences an RV to return the SV.
771 =for apidoc Am|IV|SvIVX|SV* sv
772 Returns the raw value in the SV's IV slot, without checks or conversions.
773 Only use when you are sure C<SvIOK> is true. See also C<L</SvIV>>.
775 =for apidoc Am|UV|SvUVX|SV* sv
776 Returns the raw value in the SV's UV slot, without checks or conversions.
777 Only use when you are sure C<SvIOK> is true. See also C<L</SvUV>>.
779 =for apidoc AmD|UV|SvUVXx|SV* sv
780 This is an unnecessary synonym for L</SvUVX>
782 =for apidoc Am|NV|SvNVX|SV* sv
783 Returns the raw value in the SV's NV slot, without checks or conversions.
784 Only use when you are sure C<SvNOK> is true. See also C<L</SvNV>>.
786 =for apidoc Am|char*|SvPVX|SV* sv
787 =for apidoc_item |char*|SvPVXx|SV* sv
788 =for apidoc_item |const char*|SvPVX_const|SV* sv
789 =for apidoc_item |char*|SvPVX_mutable|SV* sv
791 These return a pointer to the physical string in the SV. The SV must contain a
792 string. Prior to 5.9.3 it is not safe to execute these unless the SV's
795 These are also used to store the name of an autoloaded subroutine in an XS
796 AUTOLOAD routine. See L<perlguts/Autoloading with XSUBs>.
798 C<SvPVXx> is identical to C<SvPVX>.
800 C<SvPVX_mutable> is merely a synonym for C<SvPVX>, but its name emphasizes that
801 the string is modifiable by the caller.
803 C<SvPVX_const> differs in that the return value has been cast so that the
804 compiler will complain if you were to try to modify the contents of the string,
805 (unless you cast away const yourself).
807 =for apidoc Am|STRLEN|SvCUR|SV* sv
808 Returns the length, in bytes, of the PV inside the SV.
809 Note that this may not match Perl's C<length>; for that, use
810 C<sv_len_utf8(sv)>. See C<L</SvLEN>> also.
812 =for apidoc Am|STRLEN|SvLEN|SV* sv
813 Returns the size of the string buffer in the SV, not including any part
814 attributable to C<SvOOK>. See C<L</SvCUR>>.
816 =for apidoc Am|char*|SvEND|SV* sv
817 Returns a pointer to the spot just after the last character in
818 the string which is in the SV, where there is usually a trailing
819 C<NUL> character (even though Perl scalars do not strictly require it).
820 See C<L</SvCUR>>. Access the character as C<*(SvEND(sv))>.
822 Warning: If C<SvCUR> is equal to C<SvLEN>, then C<SvEND> points to
825 =for apidoc Am|HV*|SvSTASH|SV* sv
826 Returns the stash of the SV.
828 =for apidoc Am|void|SvIV_set|SV* sv|IV val
829 Set the value of the IV pointer in sv to val. It is possible to perform
830 the same function of this macro with an lvalue assignment to C<SvIVX>.
831 With future Perls, however, it will be more efficient to use
832 C<SvIV_set> instead of the lvalue assignment to C<SvIVX>.
834 =for apidoc Am|void|SvNV_set|SV* sv|NV val
835 Set the value of the NV pointer in C<sv> to val. See C<L</SvIV_set>>.
837 =for apidoc Am|void|SvPV_set|SV* sv|char* val
838 This is probably not what you want to use, you probably wanted
839 L</sv_usepvn_flags> or L</sv_setpvn> or L</sv_setpvs>.
841 Set the value of the PV pointer in C<sv> to the Perl allocated
842 C<NUL>-terminated string C<val>. See also C<L</SvIV_set>>.
844 Remember to free the previous PV buffer. There are many things to check.
845 Beware that the existing pointer may be involved in copy-on-write or other
846 mischief, so do C<SvOOK_off(sv)> and use C<sv_force_normal> or
847 C<SvPV_force> (or check the C<SvIsCOW> flag) first to make sure this
848 modification is safe. Then finally, if it is not a COW, call
849 C<L</SvPV_free>> to free the previous PV buffer.
851 =for apidoc Am|void|SvUV_set|SV* sv|UV val
852 Set the value of the UV pointer in C<sv> to val. See C<L</SvIV_set>>.
854 =for apidoc Am|void|SvRV_set|SV* sv|SV* val
855 Set the value of the RV pointer in C<sv> to val. See C<L</SvIV_set>>.
857 =for apidoc Am|void|SvMAGIC_set|SV* sv|MAGIC* val
858 Set the value of the MAGIC pointer in C<sv> to val. See C<L</SvIV_set>>.
860 =for apidoc Am|void|SvSTASH_set|SV* sv|HV* val
861 Set the value of the STASH pointer in C<sv> to val. See C<L</SvIV_set>>.
863 =for apidoc Am|void|SvCUR_set|SV* sv|STRLEN len
864 Sets the current length, in bytes, of the C string which is in the SV.
865 See C<L</SvCUR>> and C<SvIV_set>>.
867 =for apidoc Am|void|SvLEN_set|SV* sv|STRLEN len
868 Set the size of the string buffer for the SV. See C<L</SvLEN>>.
873 #define SvNIOK(sv) (SvFLAGS(sv) & (SVf_IOK|SVf_NOK))
874 #define SvNIOKp(sv) (SvFLAGS(sv) & (SVp_IOK|SVp_NOK))
875 #define SvNIOK_off(sv) (SvFLAGS(sv) &= ~(SVf_IOK|SVf_NOK| \
876 SVp_IOK|SVp_NOK|SVf_IVisUV))
878 #define assert_not_ROK(sv) assert_(!SvROK(sv) || !SvRV(sv))
879 #define assert_not_glob(sv) assert_(!isGV_with_GP(sv))
881 #define SvOK(sv) (SvFLAGS(sv) & SVf_OK)
882 #define SvOK_off(sv) (assert_not_ROK(sv) assert_not_glob(sv) \
883 SvFLAGS(sv) &= ~(SVf_OK| \
884 SVf_IVisUV|SVf_UTF8), \
886 #define SvOK_off_exc_UV(sv) (assert_not_ROK(sv) \
887 SvFLAGS(sv) &= ~(SVf_OK| \
891 #define SvOKp(sv) (SvFLAGS(sv) & (SVp_IOK|SVp_NOK|SVp_POK))
892 #define SvIOKp(sv) (SvFLAGS(sv) & SVp_IOK)
893 #define SvIOKp_on(sv) (assert_not_glob(sv) \
894 SvFLAGS(sv) |= SVp_IOK)
895 #define SvNOKp(sv) (SvFLAGS(sv) & SVp_NOK)
896 #define SvNOKp_on(sv) (assert_not_glob(sv) SvFLAGS(sv) |= SVp_NOK)
897 #define SvPOKp(sv) (SvFLAGS(sv) & SVp_POK)
898 #define SvPOKp_on(sv) (assert_not_ROK(sv) assert_not_glob(sv) \
899 SvFLAGS(sv) |= SVp_POK)
901 #define SvIOK(sv) (SvFLAGS(sv) & SVf_IOK)
902 #define SvIOK_on(sv) (assert_not_glob(sv) \
903 SvFLAGS(sv) |= (SVf_IOK|SVp_IOK))
904 #define SvIOK_off(sv) (SvFLAGS(sv) &= ~(SVf_IOK|SVp_IOK|SVf_IVisUV))
905 #define SvIOK_only(sv) (SvOK_off(sv), \
906 SvFLAGS(sv) |= (SVf_IOK|SVp_IOK))
907 #define SvIOK_only_UV(sv) (assert_not_glob(sv) SvOK_off_exc_UV(sv), \
908 SvFLAGS(sv) |= (SVf_IOK|SVp_IOK))
910 #define SvIOK_UV(sv) ((SvFLAGS(sv) & (SVf_IOK|SVf_IVisUV)) \
911 == (SVf_IOK|SVf_IVisUV))
912 #define SvUOK(sv) SvIOK_UV(sv)
913 #define SvIOK_notUV(sv) ((SvFLAGS(sv) & (SVf_IOK|SVf_IVisUV)) \
916 #define SvIsUV(sv) (SvFLAGS(sv) & SVf_IVisUV)
917 #define SvIsUV_on(sv) (SvFLAGS(sv) |= SVf_IVisUV)
918 #define SvIsUV_off(sv) (SvFLAGS(sv) &= ~SVf_IVisUV)
920 #define SvNOK(sv) (SvFLAGS(sv) & SVf_NOK)
921 #define SvNOK_on(sv) (assert_not_glob(sv) \
922 SvFLAGS(sv) |= (SVf_NOK|SVp_NOK))
923 #define SvNOK_off(sv) (SvFLAGS(sv) &= ~(SVf_NOK|SVp_NOK))
924 #define SvNOK_only(sv) (SvOK_off(sv), \
925 SvFLAGS(sv) |= (SVf_NOK|SVp_NOK))
928 =for apidoc Am|U32|SvUTF8|SV* sv
929 Returns a U32 value indicating the UTF-8 status of an SV. If things are set-up
930 properly, this indicates whether or not the SV contains UTF-8 encoded data.
931 You should use this I<after> a call to C<L</SvPV>> or one of its variants, in
932 case any call to string overloading updates the internal flag.
934 If you want to take into account the L<bytes> pragma, use C<L</DO_UTF8>>
937 =for apidoc Am|void|SvUTF8_on|SV *sv
938 Turn on the UTF-8 status of an SV (the data is not changed, just the flag).
939 Do not use frivolously.
941 =for apidoc Am|void|SvUTF8_off|SV *sv
942 Unsets the UTF-8 status of an SV (the data is not changed, just the flag).
943 Do not use frivolously.
945 =for apidoc Am|void|SvPOK_only_UTF8|SV* sv
946 Tells an SV that it is a string and disables all other C<OK> bits,
947 and leaves the UTF-8 status as it was.
952 /* Ensure the return value of this macro does not clash with the GV_ADD* flags
954 #define SvUTF8(sv) (SvFLAGS(sv) & SVf_UTF8)
955 #define SvUTF8_on(sv) (SvFLAGS(sv) |= (SVf_UTF8))
956 #define SvUTF8_off(sv) (SvFLAGS(sv) &= ~(SVf_UTF8))
958 #define SvPOK(sv) (SvFLAGS(sv) & SVf_POK)
959 #define SvPOK_on(sv) (assert_not_ROK(sv) assert_not_glob(sv) \
960 SvFLAGS(sv) |= (SVf_POK|SVp_POK))
961 #define SvPOK_off(sv) (SvFLAGS(sv) &= ~(SVf_POK|SVp_POK))
962 #define SvPOK_only(sv) (assert_not_ROK(sv) assert_not_glob(sv) \
963 SvFLAGS(sv) &= ~(SVf_OK| \
964 SVf_IVisUV|SVf_UTF8), \
965 SvFLAGS(sv) |= (SVf_POK|SVp_POK))
966 #define SvPOK_only_UTF8(sv) (assert_not_ROK(sv) assert_not_glob(sv) \
967 SvFLAGS(sv) &= ~(SVf_OK| \
969 SvFLAGS(sv) |= (SVf_POK|SVp_POK))
971 #define SvVOK(sv) (SvMAGICAL(sv) \
972 && mg_find(sv,PERL_MAGIC_vstring))
974 =for apidoc Am|MAGIC*|SvVSTRING_mg|SV * sv
976 Returns the vstring magic, or NULL if none
980 #define SvVSTRING_mg(sv) (SvMAGICAL(sv) \
981 ? mg_find(sv,PERL_MAGIC_vstring) : NULL)
983 #define SvOOK(sv) (SvFLAGS(sv) & SVf_OOK)
984 #define SvOOK_on(sv) (SvFLAGS(sv) |= SVf_OOK)
988 =for apidoc Am|void|SvOOK_off|SV * sv
990 Remove any string offset.
995 #define SvOOK_off(sv) ((void)(SvOOK(sv) && (sv_backoff(sv),0)))
997 #define SvFAKE(sv) (SvFLAGS(sv) & SVf_FAKE)
998 #define SvFAKE_on(sv) (SvFLAGS(sv) |= SVf_FAKE)
999 #define SvFAKE_off(sv) (SvFLAGS(sv) &= ~SVf_FAKE)
1001 #define SvROK(sv) (SvFLAGS(sv) & SVf_ROK)
1002 #define SvROK_on(sv) (SvFLAGS(sv) |= SVf_ROK)
1003 #define SvROK_off(sv) (SvFLAGS(sv) &= ~(SVf_ROK))
1005 #define SvMAGICAL(sv) (SvFLAGS(sv) & (SVs_GMG|SVs_SMG|SVs_RMG))
1006 #define SvMAGICAL_on(sv) (SvFLAGS(sv) |= (SVs_GMG|SVs_SMG|SVs_RMG))
1007 #define SvMAGICAL_off(sv) (SvFLAGS(sv) &= ~(SVs_GMG|SVs_SMG|SVs_RMG))
1009 #define SvGMAGICAL(sv) (SvFLAGS(sv) & SVs_GMG)
1010 #define SvGMAGICAL_on(sv) (SvFLAGS(sv) |= SVs_GMG)
1011 #define SvGMAGICAL_off(sv) (SvFLAGS(sv) &= ~SVs_GMG)
1013 #define SvSMAGICAL(sv) (SvFLAGS(sv) & SVs_SMG)
1014 #define SvSMAGICAL_on(sv) (SvFLAGS(sv) |= SVs_SMG)
1015 #define SvSMAGICAL_off(sv) (SvFLAGS(sv) &= ~SVs_SMG)
1017 #define SvRMAGICAL(sv) (SvFLAGS(sv) & SVs_RMG)
1018 #define SvRMAGICAL_on(sv) (SvFLAGS(sv) |= SVs_RMG)
1019 #define SvRMAGICAL_off(sv) (SvFLAGS(sv) &= ~SVs_RMG)
1021 #define SvAMAGIC(sv) (SvROK(sv) && SvOBJECT(SvRV(sv)) && \
1022 HvAMAGIC(SvSTASH(SvRV(sv))))
1024 /* To be used on the stashes themselves: */
1025 #define HvAMAGIC(hv) (SvFLAGS(hv) & SVf_AMAGIC)
1026 #define HvAMAGIC_on(hv) (SvFLAGS(hv) |= SVf_AMAGIC)
1027 #define HvAMAGIC_off(hv) (SvFLAGS(hv) &=~ SVf_AMAGIC)
1030 /* "nog" means "doesn't have get magic" */
1031 #define SvPOK_nog(sv) ((SvFLAGS(sv) & (SVf_POK|SVs_GMG)) == SVf_POK)
1032 #define SvIOK_nog(sv) ((SvFLAGS(sv) & (SVf_IOK|SVs_GMG)) == SVf_IOK)
1033 #define SvUOK_nog(sv) ((SvFLAGS(sv) & (SVf_IOK|SVf_IVisUV|SVs_GMG)) == (SVf_IOK|SVf_IVisUV))
1034 #define SvNOK_nog(sv) ((SvFLAGS(sv) & (SVf_NOK|SVs_GMG)) == SVf_NOK)
1035 #define SvNIOK_nog(sv) (SvNIOK(sv) && !(SvFLAGS(sv) & SVs_GMG))
1037 #define SvPOK_nogthink(sv) ((SvFLAGS(sv) & (SVf_POK|SVf_THINKFIRST|SVs_GMG)) == SVf_POK)
1038 #define SvIOK_nogthink(sv) ((SvFLAGS(sv) & (SVf_IOK|SVf_THINKFIRST|SVs_GMG)) == SVf_IOK)
1039 #define SvUOK_nogthink(sv) ((SvFLAGS(sv) & (SVf_IOK|SVf_IVisUV|SVf_THINKFIRST|SVs_GMG)) == (SVf_IOK|SVf_IVisUV))
1040 #define SvNOK_nogthink(sv) ((SvFLAGS(sv) & (SVf_NOK|SVf_THINKFIRST|SVs_GMG)) == SVf_NOK)
1041 #define SvNIOK_nogthink(sv) (SvNIOK(sv) && !(SvFLAGS(sv) & (SVf_THINKFIRST|SVs_GMG)))
1043 #define SvPOK_utf8_nog(sv) ((SvFLAGS(sv) & (SVf_POK|SVf_UTF8|SVs_GMG)) == (SVf_POK|SVf_UTF8))
1044 #define SvPOK_utf8_nogthink(sv) ((SvFLAGS(sv) & (SVf_POK|SVf_UTF8|SVf_THINKFIRST|SVs_GMG)) == (SVf_POK|SVf_UTF8))
1046 #define SvPOK_byte_nog(sv) ((SvFLAGS(sv) & (SVf_POK|SVf_UTF8|SVs_GMG)) == SVf_POK)
1047 #define SvPOK_byte_nogthink(sv) ((SvFLAGS(sv) & (SVf_POK|SVf_UTF8|SVf_THINKFIRST|SVs_GMG)) == SVf_POK)
1049 #define SvPOK_pure_nogthink(sv) \
1050 ((SvFLAGS(sv) & (SVf_POK|SVf_IOK|SVf_NOK|SVf_ROK|SVpgv_GP|SVf_THINKFIRST|SVs_GMG)) == SVf_POK)
1051 #define SvPOK_utf8_pure_nogthink(sv) \
1052 ((SvFLAGS(sv) & (SVf_POK|SVf_UTF8|SVf_IOK|SVf_NOK|SVf_ROK|SVpgv_GP|SVf_THINKFIRST|SVs_GMG)) == (SVf_POK|SVf_UTF8))
1053 #define SvPOK_byte_pure_nogthink(sv) \
1054 ((SvFLAGS(sv) & (SVf_POK|SVf_UTF8|SVf_IOK|SVf_NOK|SVf_ROK|SVpgv_GP|SVf_THINKFIRST|SVs_GMG)) == SVf_POK)
1057 =for apidoc Am|bool|SvIsBOOL|SV* sv
1059 Returns true if the SV is one of the special boolean constants (PL_sv_yes or
1060 PL_sv_no), or is a regular SV whose last assignment stored a copy of one.
1065 #define SvIsBOOL(sv) Perl_sv_isbool(aTHX_ sv)
1068 =for apidoc Am|U32|SvGAMAGIC|SV* sv
1070 Returns true if the SV has get magic or
1071 overloading. If either is true then
1072 the scalar is active data, and has the potential to return a new value every
1073 time it is accessed. Hence you must be careful to
1074 only read it once per user logical operation and work
1075 with that returned value. If neither is true then
1076 the scalar's value cannot change unless written to.
1081 #define SvGAMAGIC(sv) (SvGMAGICAL(sv) || SvAMAGIC(sv))
1083 #define Gv_AMG(stash) \
1084 (HvNAME(stash) && Gv_AMupdate(stash,FALSE) \
1086 : (HvAMAGIC_off(stash), 0))
1088 #define SvWEAKREF(sv) ((SvFLAGS(sv) & (SVf_ROK|SVprv_WEAKREF)) \
1089 == (SVf_ROK|SVprv_WEAKREF))
1090 #define SvWEAKREF_on(sv) (SvFLAGS(sv) |= (SVf_ROK|SVprv_WEAKREF))
1091 #define SvWEAKREF_off(sv) (SvFLAGS(sv) &= ~(SVf_ROK|SVprv_WEAKREF))
1093 #define SvPCS_IMPORTED(sv) ((SvFLAGS(sv) & (SVf_ROK|SVprv_PCS_IMPORTED)) \
1094 == (SVf_ROK|SVprv_PCS_IMPORTED))
1095 #define SvPCS_IMPORTED_on(sv) (SvFLAGS(sv) |= (SVf_ROK|SVprv_PCS_IMPORTED))
1096 #define SvPCS_IMPORTED_off(sv) (SvFLAGS(sv) &= ~(SVf_ROK|SVprv_PCS_IMPORTED))
1099 =for apidoc m|U32|SvTHINKFIRST|SV *sv
1101 A quick flag check to see whether an C<sv> should be passed to C<sv_force_normal>
1102 to be "downgraded" before C<SvIVX> or C<SvPVX> can be modified directly.
1104 For example, if your scalar is a reference and you want to modify the C<SvIVX>
1105 slot, you can't just do C<SvROK_off>, as that will leak the referent.
1107 This is used internally by various sv-modifying functions, such as
1108 C<sv_setsv>, C<sv_setiv> and C<sv_pvn_force>.
1110 One case that this does not handle is a gv without SvFAKE set. After
1112 if (SvTHINKFIRST(gv)) sv_force_normal(gv);
1114 it will still be a gv.
1116 C<SvTHINKFIRST> sometimes produces false positives. In those cases
1117 C<sv_force_normal> does nothing.
1122 #define SvTHINKFIRST(sv) (SvFLAGS(sv) & SVf_THINKFIRST)
1125 #define SvPADMY(sv) !(SvFLAGS(sv) & SVs_PADTMP)
1127 # define SvPADMY_on(sv) SvPADTMP_off(sv)
1130 #define SvPADTMP(sv) (SvFLAGS(sv) & (SVs_PADTMP))
1131 #define SvPADSTALE(sv) (SvFLAGS(sv) & (SVs_PADSTALE))
1133 #define SvPADTMP_on(sv) (SvFLAGS(sv) |= SVs_PADTMP)
1134 #define SvPADTMP_off(sv) (SvFLAGS(sv) &= ~SVs_PADTMP)
1135 #define SvPADSTALE_on(sv) Perl_SvPADSTALE_on(MUTABLE_SV(sv))
1136 #define SvPADSTALE_off(sv) Perl_SvPADSTALE_off(MUTABLE_SV(sv))
1138 #define SvTEMP(sv) (SvFLAGS(sv) & SVs_TEMP)
1139 #define SvTEMP_on(sv) (SvFLAGS(sv) |= SVs_TEMP)
1140 #define SvTEMP_off(sv) (SvFLAGS(sv) &= ~SVs_TEMP)
1142 #define SvOBJECT(sv) (SvFLAGS(sv) & SVs_OBJECT)
1143 #define SvOBJECT_on(sv) (SvFLAGS(sv) |= SVs_OBJECT)
1144 #define SvOBJECT_off(sv) (SvFLAGS(sv) &= ~SVs_OBJECT)
1147 =for apidoc Am|U32|SvREADONLY|SV* sv
1148 Returns true if the argument is readonly, otherwise returns false.
1149 Exposed to perl code via Internals::SvREADONLY().
1151 =for apidoc Am|U32|SvREADONLY_on|SV* sv
1152 Mark an object as readonly. Exactly what this means depends on the object
1153 type. Exposed to perl code via Internals::SvREADONLY().
1155 =for apidoc Am|U32|SvREADONLY_off|SV* sv
1156 Mark an object as not-readonly. Exactly what this mean depends on the
1157 object type. Exposed to perl code via Internals::SvREADONLY().
1162 #define SvREADONLY(sv) (SvFLAGS(sv) & (SVf_READONLY|SVf_PROTECT))
1164 # define SvREADONLY_on(sv) (SvFLAGS(sv) |= (SVf_READONLY|SVf_PROTECT))
1165 # define SvREADONLY_off(sv) (SvFLAGS(sv) &=~(SVf_READONLY|SVf_PROTECT))
1167 # define SvREADONLY_on(sv) (SvFLAGS(sv) |= SVf_READONLY)
1168 # define SvREADONLY_off(sv) (SvFLAGS(sv) &= ~SVf_READONLY)
1171 #define SvSCREAM(sv) ((SvFLAGS(sv) & (SVp_SCREAM|SVp_POK)) == (SVp_SCREAM|SVp_POK))
1172 #define SvSCREAM_on(sv) (SvFLAGS(sv) |= SVp_SCREAM)
1173 #define SvSCREAM_off(sv) (SvFLAGS(sv) &= ~SVp_SCREAM)
1176 # define SvCOMPILED(sv) 0
1177 # define SvCOMPILED_on(sv)
1178 # define SvCOMPILED_off(sv)
1182 #if defined (DEBUGGING) && defined(PERL_USE_GCC_BRACE_GROUPS)
1183 # define SvTAIL(sv) ({ const SV *const _svtail = (const SV *)(sv); \
1184 assert(SvTYPE(_svtail) != SVt_PVAV); \
1185 assert(SvTYPE(_svtail) != SVt_PVHV); \
1186 assert(!(SvFLAGS(_svtail) & (SVf_NOK|SVp_NOK))); \
1187 assert(SvVALID(_svtail)); \
1188 ((XPVNV*)SvANY(_svtail))->xnv_u.xnv_bm_tail; \
1191 # define SvTAIL(_svtail) (((XPVNV*)SvANY(_svtail))->xnv_u.xnv_bm_tail)
1194 /* Does the SV have a Boyer-Moore table attached as magic?
1195 * 'VALID' is a poor name, but is kept for historical reasons. */
1196 #define SvVALID(_svvalid) ( \
1198 && SvSMAGICAL(_svvalid) \
1199 && SvMAGIC(_svvalid) \
1200 && (SvMAGIC(_svvalid)->mg_type == PERL_MAGIC_bm \
1201 || mg_find(_svvalid, PERL_MAGIC_bm)) \
1204 #define SvRVx(sv) SvRV(sv)
1206 #ifdef PERL_DEBUG_COW
1207 /* Need -0.0 for SvNVX to preserve IEEE FP "negative zero" because
1208 +0.0 + -0.0 => +0.0 but -0.0 + -0.0 => -0.0 */
1209 # define SvIVX(sv) (0 + ((XPVIV*) SvANY(sv))->xiv_iv)
1210 # define SvUVX(sv) (0 + ((XPVUV*) SvANY(sv))->xuv_uv)
1211 # define SvNVX(sv) (-0.0 + ((XPVNV*) SvANY(sv))->xnv_u.xnv_nv)
1212 # define SvRV(sv) (0 + (sv)->sv_u.svu_rv)
1213 # define SvRV_const(sv) (0 + (sv)->sv_u.svu_rv)
1214 /* Don't test the core XS code yet. */
1215 # if defined (PERL_CORE) && PERL_DEBUG_COW > 1
1216 # define SvPVX(sv) (0 + (assert_(!SvREADONLY(sv)) (sv)->sv_u.svu_pv))
1218 # define SvPVX(sv) SvPVX_mutable(sv)
1220 # define SvCUR(sv) (0 + ((XPV*) SvANY(sv))->xpv_cur)
1221 # define SvLEN(sv) (0 + ((XPV*) SvANY(sv))->xpv_len)
1222 # define SvEND(sv) ((sv)->sv_u.svu_pv + ((XPV*)SvANY(sv))->xpv_cur)
1224 # define SvMAGIC(sv) (0 + *(assert_(SvTYPE(sv) >= SVt_PVMG) &((XPVMG*) SvANY(sv))->xmg_u.xmg_magic))
1225 # define SvSTASH(sv) (0 + *(assert_(SvTYPE(sv) >= SVt_PVMG) &((XPVMG*) SvANY(sv))->xmg_stash))
1226 #else /* Below is not PERL_DEBUG_COW */
1228 # define SvLEN(sv) (0 + ((XPV*) SvANY(sv))->xpv_len)
1230 # define SvLEN(sv) ((XPV*) SvANY(sv))->xpv_len
1232 # define SvEND(sv) ((sv)->sv_u.svu_pv + ((XPV*)SvANY(sv))->xpv_cur)
1234 # if defined (DEBUGGING) && defined(PERL_USE_GCC_BRACE_GROUPS)
1235 /* These get expanded inside other macros that already use a variable _sv */
1236 # define SvPVX(sv) \
1237 (*({ SV *const _svpvx = MUTABLE_SV(sv); \
1238 assert(PL_valid_types_PVX[SvTYPE(_svpvx) & SVt_MASK]); \
1239 assert(!isGV_with_GP(_svpvx)); \
1240 assert(!(SvTYPE(_svpvx) == SVt_PVIO \
1241 && !(IoFLAGS(_svpvx) & IOf_FAKE_DIRP))); \
1242 &((_svpvx)->sv_u.svu_pv); \
1245 # define SvCUR(sv) \
1246 ({ const SV *const _svcur = (const SV *)(sv); \
1247 assert(PL_valid_types_PVX[SvTYPE(_svcur) & SVt_MASK]); \
1248 assert(!isGV_with_GP(_svcur)); \
1249 assert(!(SvTYPE(_svcur) == SVt_PVIO \
1250 && !(IoFLAGS(_svcur) & IOf_FAKE_DIRP))); \
1251 (((XPV*) MUTABLE_PTR(SvANY(_svcur)))->xpv_cur); \
1254 # define SvCUR(sv) \
1255 (*({ const SV *const _svcur = (const SV *)(sv); \
1256 assert(PL_valid_types_PVX[SvTYPE(_svcur) & SVt_MASK]); \
1257 assert(!isGV_with_GP(_svcur)); \
1258 assert(!(SvTYPE(_svcur) == SVt_PVIO \
1259 && !(IoFLAGS(_svcur) & IOf_FAKE_DIRP))); \
1260 &(((XPV*) MUTABLE_PTR(SvANY(_svcur)))->xpv_cur); \
1263 # define SvIVX(sv) \
1264 (*({ const SV *const _svivx = (const SV *)(sv); \
1265 assert(PL_valid_types_IVX[SvTYPE(_svivx) & SVt_MASK]); \
1266 assert(!isGV_with_GP(_svivx)); \
1267 &(((XPVIV*) MUTABLE_PTR(SvANY(_svivx)))->xiv_iv); \
1269 # define SvUVX(sv) \
1270 (*({ const SV *const _svuvx = (const SV *)(sv); \
1271 assert(PL_valid_types_IVX[SvTYPE(_svuvx) & SVt_MASK]); \
1272 assert(!isGV_with_GP(_svuvx)); \
1273 &(((XPVUV*) MUTABLE_PTR(SvANY(_svuvx)))->xuv_uv); \
1275 # define SvNVX(sv) \
1276 (*({ const SV *const _svnvx = (const SV *)(sv); \
1277 assert(PL_valid_types_NVX[SvTYPE(_svnvx) & SVt_MASK]); \
1278 assert(!isGV_with_GP(_svnvx)); \
1279 &(((XPVNV*) MUTABLE_PTR(SvANY(_svnvx)))->xnv_u.xnv_nv); \
1282 (*({ SV *const _svrv = MUTABLE_SV(sv); \
1283 assert(PL_valid_types_RV[SvTYPE(_svrv) & SVt_MASK]); \
1284 assert(!isGV_with_GP(_svrv)); \
1285 assert(!(SvTYPE(_svrv) == SVt_PVIO \
1286 && !(IoFLAGS(_svrv) & IOf_FAKE_DIRP))); \
1287 &((_svrv)->sv_u.svu_rv); \
1289 # define SvRV_const(sv) \
1290 ({ const SV *const _svrv = (const SV *)(sv); \
1291 assert(PL_valid_types_RV[SvTYPE(_svrv) & SVt_MASK]); \
1292 assert(!isGV_with_GP(_svrv)); \
1293 assert(!(SvTYPE(_svrv) == SVt_PVIO \
1294 && !(IoFLAGS(_svrv) & IOf_FAKE_DIRP))); \
1295 (_svrv)->sv_u.svu_rv; \
1297 # define SvMAGIC(sv) \
1298 (*({ const SV *const _svmagic = (const SV *)(sv); \
1299 assert(SvTYPE(_svmagic) >= SVt_PVMG); \
1300 &(((XPVMG*) MUTABLE_PTR(SvANY(_svmagic)))->xmg_u.xmg_magic); \
1302 # define SvSTASH(sv) \
1303 (*({ const SV *const _svstash = (const SV *)(sv); \
1304 assert(SvTYPE(_svstash) >= SVt_PVMG); \
1305 &(((XPVMG*) MUTABLE_PTR(SvANY(_svstash)))->xmg_stash); \
1307 # else /* Below is not DEBUGGING or can't use brace groups */
1308 # define SvPVX(sv) ((sv)->sv_u.svu_pv)
1309 # define SvCUR(sv) ((XPV*) SvANY(sv))->xpv_cur
1310 # define SvIVX(sv) ((XPVIV*) SvANY(sv))->xiv_iv
1311 # define SvUVX(sv) ((XPVUV*) SvANY(sv))->xuv_uv
1312 # define SvNVX(sv) ((XPVNV*) SvANY(sv))->xnv_u.xnv_nv
1313 # define SvRV(sv) ((sv)->sv_u.svu_rv)
1314 # define SvRV_const(sv) (0 + (sv)->sv_u.svu_rv)
1315 # define SvMAGIC(sv) ((XPVMG*) SvANY(sv))->xmg_u.xmg_magic
1316 # define SvSTASH(sv) ((XPVMG*) SvANY(sv))->xmg_stash
1321 /* Given that these two are new, there can't be any existing code using them
1322 * as LVALUEs, so prevent that from happening */
1323 # define SvPVX_mutable(sv) (0 + (sv)->sv_u.svu_pv)
1324 # define SvPVX_const(sv) ((const char*)(0 + (sv)->sv_u.svu_pv))
1326 /* Except for the poison code, which uses & to scribble over the pointer after
1327 free() is called. */
1328 # define SvPVX_mutable(sv) ((sv)->sv_u.svu_pv)
1329 # define SvPVX_const(sv) ((const char*)((sv)->sv_u.svu_pv))
1332 #define SvIVXx(sv) SvIVX(sv)
1333 #define SvUVXx(sv) SvUVX(sv)
1334 #define SvNVXx(sv) SvNVX(sv)
1335 #define SvPVXx(sv) SvPVX(sv)
1336 #define SvLENx(sv) SvLEN(sv)
1337 #define SvENDx(sv) ((PL_Sv = (sv)), SvEND(PL_Sv))
1340 /* Ask a scalar nicely to try to become an IV, if possible.
1341 Not guaranteed to stay returning void */
1342 /* Macro won't actually call sv_2iv if already IOK */
1343 #define SvIV_please(sv) \
1344 STMT_START {if (!SvIOKp(sv) && (SvFLAGS(sv) & (SVf_NOK|SVf_POK))) \
1345 (void) SvIV(sv); } STMT_END
1346 #define SvIV_please_nomg(sv) \
1347 (!(SvFLAGS(sv) & (SVf_IOK|SVp_IOK)) && (SvFLAGS(sv) & (SVf_NOK|SVf_POK)) \
1348 ? (sv_2iv_flags(sv, 0), SvIOK(sv)) \
1350 #define SvIV_set(sv, val) \
1352 assert(PL_valid_types_IV_set[SvTYPE(sv) & SVt_MASK]); \
1353 assert(!isGV_with_GP(sv)); \
1354 (((XPVIV*) SvANY(sv))->xiv_iv = (val)); } STMT_END
1355 #define SvNV_set(sv, val) \
1357 assert(PL_valid_types_NV_set[SvTYPE(sv) & SVt_MASK]); \
1358 assert(!isGV_with_GP(sv)); \
1359 (((XPVNV*)SvANY(sv))->xnv_u.xnv_nv = (val)); } STMT_END
1360 #define SvPV_set(sv, val) \
1362 assert(PL_valid_types_PVX[SvTYPE(sv) & SVt_MASK]); \
1363 assert(!isGV_with_GP(sv)); \
1364 assert(!(SvTYPE(sv) == SVt_PVIO \
1365 && !(IoFLAGS(sv) & IOf_FAKE_DIRP))); \
1366 ((sv)->sv_u.svu_pv = (val)); } STMT_END
1367 #define SvUV_set(sv, val) \
1369 assert(PL_valid_types_IV_set[SvTYPE(sv) & SVt_MASK]); \
1370 assert(!isGV_with_GP(sv)); \
1371 (((XPVUV*)SvANY(sv))->xuv_uv = (val)); } STMT_END
1372 #define SvRV_set(sv, val) \
1374 assert(PL_valid_types_RV[SvTYPE(sv) & SVt_MASK]); \
1375 assert(!isGV_with_GP(sv)); \
1376 assert(!(SvTYPE(sv) == SVt_PVIO \
1377 && !(IoFLAGS(sv) & IOf_FAKE_DIRP))); \
1378 ((sv)->sv_u.svu_rv = (val)); } STMT_END
1379 #define SvMAGIC_set(sv, val) \
1380 STMT_START { assert(SvTYPE(sv) >= SVt_PVMG); \
1381 (((XPVMG*)SvANY(sv))->xmg_u.xmg_magic = (val)); } STMT_END
1382 #define SvSTASH_set(sv, val) \
1383 STMT_START { assert(SvTYPE(sv) >= SVt_PVMG); \
1384 (((XPVMG*) SvANY(sv))->xmg_stash = (val)); } STMT_END
1385 #define SvCUR_set(sv, val) \
1387 assert(PL_valid_types_PVX[SvTYPE(sv) & SVt_MASK]); \
1388 assert(!isGV_with_GP(sv)); \
1389 assert(!(SvTYPE(sv) == SVt_PVIO \
1390 && !(IoFLAGS(sv) & IOf_FAKE_DIRP))); \
1391 (((XPV*) SvANY(sv))->xpv_cur = (val)); } STMT_END
1392 #define SvLEN_set(sv, val) \
1394 assert(PL_valid_types_PVX[SvTYPE(sv) & SVt_MASK]); \
1395 assert(!isGV_with_GP(sv)); \
1396 assert(!(SvTYPE(sv) == SVt_PVIO \
1397 && !(IoFLAGS(sv) & IOf_FAKE_DIRP))); \
1398 (((XPV*) SvANY(sv))->xpv_len = (val)); } STMT_END
1399 #define SvEND_set(sv, val) \
1400 STMT_START { assert(SvTYPE(sv) >= SVt_PV); \
1401 SvCUR_set(sv, (val) - SvPVX(sv)); } STMT_END
1404 =for apidoc Am|void|SvPV_renew|SV* sv|STRLEN len
1405 Low level micro optimization of C<L</SvGROW>>. It is generally better to use
1406 C<SvGROW> instead. This is because C<SvPV_renew> ignores potential issues that
1407 C<SvGROW> handles. C<sv> needs to have a real C<PV> that is unencombered by
1408 things like COW. Using C<SV_CHECK_THINKFIRST> or
1409 C<SV_CHECK_THINKFIRST_COW_DROP> before calling this should clean it up, but
1410 why not just use C<SvGROW> if you're not sure about the provenance?
1414 #define SvPV_renew(sv,n) \
1415 STMT_START { SvLEN_set(sv, n); \
1416 SvPV_set((sv), (MEM_WRAP_CHECK_(n,char) \
1417 (char*)saferealloc((Malloc_t)SvPVX(sv), \
1418 (MEM_SIZE)((n))))); \
1421 #define SvPV_shrink_to_cur(sv) STMT_START { \
1422 const STRLEN _lEnGtH = SvCUR(sv) + 1; \
1423 SvPV_renew(sv, _lEnGtH); \
1427 =for apidoc Am|void|SvPV_free|SV * sv
1429 Frees the PV buffer in C<sv>, leaving things in a precarious state, so should
1430 only be used as part of a larger operation
1434 #define SvPV_free(sv) \
1436 assert(SvTYPE(sv) >= SVt_PV); \
1438 assert(!SvROK(sv)); \
1439 if(UNLIKELY(SvOOK(sv))) { \
1441 SvOOK_offset(sv, zok); \
1442 SvPV_set(sv, SvPVX_mutable(sv) - zok); \
1443 SvFLAGS(sv) &= ~SVf_OOK; \
1445 Safefree(SvPVX(sv)); \
1450 /* Code that crops up in three places to take a scalar and ready it to hold
1452 # define prepare_SV_for_RV(sv) \
1454 if (SvTYPE(sv) < SVt_PV && SvTYPE(sv) != SVt_IV) \
1455 sv_upgrade(sv, SVt_IV); \
1456 else if (SvTYPE(sv) >= SVt_PV) { \
1465 # define BmFLAGS(sv) (SvTAIL(sv) ? FBMcf_TAIL : 0)
1468 #if defined (DEBUGGING) && defined(PERL_USE_GCC_BRACE_GROUPS)
1469 # define BmUSEFUL(sv) \
1470 (*({ SV *const _bmuseful = MUTABLE_SV(sv); \
1471 assert(SvTYPE(_bmuseful) >= SVt_PVIV); \
1472 assert(SvVALID(_bmuseful)); \
1473 assert(!SvIOK(_bmuseful)); \
1474 &(((XPVIV*) SvANY(_bmuseful))->xiv_u.xivu_iv); \
1477 # define BmUSEFUL(sv) ((XPVIV*) SvANY(sv))->xiv_u.xivu_iv
1482 # define BmRARE(sv) 0
1483 # define BmPREVIOUS(sv) 0
1486 #define FmLINES(sv) ((XPVIV*) SvANY(sv))->xiv_iv
1488 #define LvTYPE(sv) ((XPVLV*) SvANY(sv))->xlv_type
1489 #define LvTARG(sv) ((XPVLV*) SvANY(sv))->xlv_targ
1490 #define LvTARGOFF(sv) ((XPVLV*) SvANY(sv))->xlv_targoff
1491 #define LvSTARGOFF(sv) ((XPVLV*) SvANY(sv))->xlv_targoff_u.xlvu_stargoff
1492 #define LvTARGLEN(sv) ((XPVLV*) SvANY(sv))->xlv_targlen
1493 #define LvFLAGS(sv) ((XPVLV*) SvANY(sv))->xlv_flags
1495 #define LVf_NEG_OFF 0x1
1496 #define LVf_NEG_LEN 0x2
1497 #define LVf_OUT_OF_RANGE 0x4
1499 #define IoIFP(sv) (sv)->sv_u.svu_fp
1500 #define IoOFP(sv) ((XPVIO*) SvANY(sv))->xio_ofp
1501 #define IoDIRP(sv) ((XPVIO*) SvANY(sv))->xio_dirp
1502 #define IoANY(sv) ((XPVIO*) SvANY(sv))->xio_any
1503 #define IoLINES(sv) ((XPVIO*) SvANY(sv))->xiv_u.xivu_iv
1504 #define IoPAGE(sv) ((XPVIO*) SvANY(sv))->xio_page
1505 #define IoPAGE_LEN(sv) ((XPVIO*) SvANY(sv))->xio_page_len
1506 #define IoLINES_LEFT(sv)((XPVIO*) SvANY(sv))->xio_lines_left
1507 #define IoTOP_NAME(sv) ((XPVIO*) SvANY(sv))->xio_top_name
1508 #define IoTOP_GV(sv) ((XPVIO*) SvANY(sv))->xio_top_gv
1509 #define IoFMT_NAME(sv) ((XPVIO*) SvANY(sv))->xio_fmt_name
1510 #define IoFMT_GV(sv) ((XPVIO*) SvANY(sv))->xio_fmt_gv
1511 #define IoBOTTOM_NAME(sv)((XPVIO*) SvANY(sv))->xio_bottom_name
1512 #define IoBOTTOM_GV(sv) ((XPVIO*) SvANY(sv))->xio_bottom_gv
1513 #define IoTYPE(sv) ((XPVIO*) SvANY(sv))->xio_type
1514 #define IoFLAGS(sv) ((XPVIO*) SvANY(sv))->xio_flags
1516 /* IoTYPE(sv) is a single character telling the type of I/O connection. */
1517 #define IoTYPE_RDONLY '<'
1518 #define IoTYPE_WRONLY '>'
1519 #define IoTYPE_RDWR '+'
1520 #define IoTYPE_APPEND 'a'
1521 #define IoTYPE_PIPE '|'
1522 #define IoTYPE_STD '-' /* stdin or stdout */
1523 #define IoTYPE_SOCKET 's'
1524 #define IoTYPE_CLOSED ' '
1525 #define IoTYPE_IMPLICIT 'I' /* stdin or stdout or stderr */
1526 #define IoTYPE_NUMERIC '#' /* fdopen */
1529 =for apidoc Am|bool|SvTAINTED|SV* sv
1530 Checks to see if an SV is tainted. Returns TRUE if it is, FALSE if
1533 =for apidoc Am|void|SvTAINTED_on|SV* sv
1534 Marks an SV as tainted if tainting is enabled.
1536 =for apidoc Am|void|SvTAINTED_off|SV* sv
1537 Untaints an SV. Be I<very> careful with this routine, as it short-circuits
1538 some of Perl's fundamental security features. XS module authors should not
1539 use this function unless they fully understand all the implications of
1540 unconditionally untainting the value. Untainting should be done in the
1541 standard perl fashion, via a carefully crafted regexp, rather than directly
1542 untainting variables.
1544 =for apidoc Am|void|SvTAINT|SV* sv
1545 Taints an SV if tainting is enabled, and if some input to the current
1546 expression is tainted--usually a variable, but possibly also implicit
1547 inputs such as locale settings. C<SvTAINT> propagates that taintedness to
1548 the outputs of an expression in a pessimistic fashion; i.e., without paying
1549 attention to precisely which outputs are influenced by which inputs.
1554 #define sv_taint(sv) sv_magic((sv), NULL, PERL_MAGIC_taint, NULL, 0)
1556 #ifdef NO_TAINT_SUPPORT
1557 # define SvTAINTED(sv) 0
1559 # define SvTAINTED(sv) (SvMAGICAL(sv) && sv_tainted(sv))
1561 #define SvTAINTED_on(sv) STMT_START{ if(UNLIKELY(TAINTING_get)){sv_taint(sv);} }STMT_END
1562 #define SvTAINTED_off(sv) STMT_START{ if(UNLIKELY(TAINTING_get)){sv_untaint(sv);} }STMT_END
1564 #define SvTAINT(sv) \
1566 assert(TAINTING_get || !TAINT_get); \
1567 if (UNLIKELY(TAINT_get)) \
1572 =for apidoc Am|char*|SvPV_force|SV* sv|STRLEN len
1573 =for apidoc_item ||SvPV_force_nolen|SV* sv
1574 =for apidoc_item ||SvPVx_force|SV* sv|STRLEN len
1575 =for apidoc_item ||SvPV_force_nomg|SV* sv|STRLEN len
1576 =for apidoc_item ||SvPV_force_nomg_nolen|SV * sv
1577 =for apidoc_item ||SvPV_force_mutable|SV * sv|STRLEN len
1578 =for apidoc_item ||SvPV_force_flags|SV * sv|STRLEN len|U32 flags
1579 =for apidoc_item ||SvPV_force_flags_nolen|SV * sv|U32 flags
1580 =for apidoc_item ||SvPV_force_flags_mutable|SV * sv|STRLEN len|U32 flags
1581 =for apidoc_item ||SvPVbyte_force
1582 =for apidoc_item ||SvPVbytex_force
1583 =for apidoc_item ||SvPVutf8_force
1584 =for apidoc_item ||SvPVutf8x_force
1586 These are like C<L</SvPV>>, returning the string in the SV, but will force the
1587 SV into containing a string (C<L</SvPOK>>), and only a string
1588 (C<L</SvPOK_only>>), by hook or by crook. You need to use one of these
1589 C<force> routines if you are going to update the C<L</SvPVX>> directly.
1591 Note that coercing an arbitrary scalar into a plain PV will potentially
1592 strip useful data from it. For example if the SV was C<SvROK>, then the
1593 referent will have its reference count decremented, and the SV itself may
1594 be converted to an C<SvPOK> scalar with a string buffer containing a value
1595 such as C<"ARRAY(0x1234)">.
1597 The differences between the forms are:
1599 The forms with C<flags> in their names allow you to use the C<flags> parameter
1600 to specify to perform 'get' magic (by setting the C<SV_GMAGIC> flag) or to skip
1601 'get' magic (by clearing it). The other forms do perform 'get' magic, except
1602 for the ones with C<nomg> in their names, which skip 'get' magic.
1604 The forms that take a C<len> parameter will set that variable to the byte
1605 length of the resultant string (these are macros, so don't use C<&len>).
1607 The forms with C<nolen> in their names indicate they don't have a C<len>
1608 parameter. They should be used only when it is known that the PV is a C
1609 string, terminated by a NUL byte, and without intermediate NUL characters; or
1610 when you don't care about its length.
1612 The forms with C<mutable> in their names are effectively the same as those without,
1613 but the name emphasizes that the string is modifiable by the caller, which it is
1616 C<SvPVutf8_force> is like C<SvPV_force>, but converts C<sv> to UTF-8 first if
1619 C<SvPVutf8x_force> is like C<SvPVutf8_force>, but guarantees to evaluate C<sv>
1620 only once; use the more efficient C<SvPVutf8_force> otherwise.
1622 C<SvPVbyte_force> is like C<SvPV_force>, but converts C<sv> to byte
1623 representation first if currently encoded as UTF-8. If the SV cannot be
1624 downgraded from UTF-8, this croaks.
1626 C<SvPVbytex_force> is like C<SvPVbyte_force>, but guarantees to evaluate C<sv>
1627 only once; use the more efficient C<SvPVbyte_force> otherwise.
1629 =for apidoc Am|char*|SvPV|SV* sv|STRLEN len
1630 =for apidoc_item |char*|SvPVx|SV* sv|STRLEN len
1631 =for apidoc_item |char*|SvPV_nomg|SV* sv|STRLEN len
1632 =for apidoc_item |char*|SvPV_nolen|SV* sv
1633 =for apidoc_item |char*|SvPVx_nolen|SV* sv
1634 =for apidoc_item |char*|SvPV_nomg_nolen|SV* sv
1635 =for apidoc_item |char*|SvPV_mutable|SV* sv|STRLEN len
1636 =for apidoc_item |const char*|SvPV_const|SV* sv|STRLEN len
1637 =for apidoc_item |const char*|SvPVx_const|SV* sv|STRLEN len
1638 =for apidoc_item |const char*|SvPV_nolen_const|SV* sv
1639 =for apidoc_item |const char*|SvPVx_nolen_const|SV* sv
1640 =for apidoc_item |const char*|SvPV_nomg_const|SV* sv|STRLEN len
1641 =for apidoc_item |const char*|SvPV_nomg_const_nolen|SV* sv
1642 =for apidoc_item |char *|SvPV_flags|SV * sv|STRLEN len|U32 flags
1643 =for apidoc_item |const char *|SvPV_flags_const|SV * sv|STRLEN len|U32 flags
1644 =for apidoc_item |char *|SvPV_flags_mutable|SV * sv|STRLEN len|U32 flags
1645 =for apidoc_item |char*|SvPVbyte|SV* sv|STRLEN len
1646 =for apidoc_item |char*|SvPVbyte_nomg|SV* sv|STRLEN len
1647 =for apidoc_item |char*|SvPVbyte_nolen|SV* sv
1648 =for apidoc_item |char*|SvPVbytex_nolen|SV* sv
1649 =for apidoc_item |char*|SvPVbytex|SV* sv|STRLEN len
1650 =for apidoc_item |char*|SvPVbyte_or_null|SV* sv|STRLEN len
1651 =for apidoc_item |char*|SvPVbyte_or_null_nomg|SV* sv|STRLEN len
1652 =for apidoc_item |char*|SvPVutf8|SV* sv|STRLEN len
1653 =for apidoc_item |char*|SvPVutf8x|SV* sv|STRLEN len
1654 =for apidoc_item |char*|SvPVutf8_nomg|SV* sv|STRLEN len
1655 =for apidoc_item |char*|SvPVutf8_nolen|SV* sv
1656 =for apidoc_item |char*|SvPVutf8_or_null|SV* sv|STRLEN len
1657 =for apidoc_item |char*|SvPVutf8_or_null_nomg|SV* sv|STRLEN len
1659 All these return a pointer to the string in C<sv>, or a stringified form of
1660 C<sv> if it does not contain a string. The SV may cache the stringified
1661 version becoming C<SvPOK>.
1663 This is a very basic and common operation, so there are lots of slightly
1664 different versions of it.
1666 Note that there is no guarantee that the return value of C<SvPV(sv)>, for
1667 example, is equal to C<SvPVX(sv)>, or that C<SvPVX(sv)> contains valid data, or
1668 that successive calls to C<SvPV(sv)> (or another of these forms) will return
1669 the same pointer value each time. This is due to the way that things like
1670 overloading and Copy-On-Write are handled. In these cases, the return value
1671 may point to a temporary buffer or similar. If you absolutely need the
1672 C<SvPVX> field to be valid (for example, if you intend to write to it), then
1673 see C<L</SvPV_force>>.
1675 The differences between the forms are:
1677 The forms with neither C<byte> nor C<utf8> in their names (e.g., C<SvPV> or
1678 C<SvPV_nolen>) can expose the SV's internal string buffer. If
1679 that buffer consists entirely of bytes 0-255 and includes any bytes above
1680 127, then you B<MUST> consult C<SvUTF8> to determine the actual code points
1681 the string is meant to contain. Generally speaking, it is probably safer to
1682 prefer C<SvPVbyte>, C<SvPVutf8>, and the like. See
1683 L<perlguts/How do I pass a Perl string to a C library?> for more details.
1685 The forms with C<flags> in their names allow you to use the C<flags> parameter
1686 to specify to process 'get' magic (by setting the C<SV_GMAGIC> flag) or to skip
1687 'get' magic (by clearing it). The other forms process 'get' magic, except for
1688 the ones with C<nomg> in their names, which skip 'get' magic.
1690 The forms that take a C<len> parameter will set that variable to the byte
1691 length of the resultant string (these are macros, so don't use C<&len>).
1693 The forms with C<nolen> in their names indicate they don't have a C<len>
1694 parameter. They should be used only when it is known that the PV is a C
1695 string, terminated by a NUL byte, and without intermediate NUL characters; or
1696 when you don't care about its length.
1698 The forms with C<const> in their names return S<C<const char *>> so that the
1699 compiler will hopefully complain if you were to try to modify the contents of
1700 the string (unless you cast away const yourself).
1702 The other forms return a mutable pointer so that the string is modifiable by
1703 the caller; this is emphasized for the ones with C<mutable> in their names.
1705 The forms whose name ends in C<x> are the same as the corresponding form
1706 without the C<x>, but the C<x> form is guaranteed to evaluate C<sv> exactly
1707 once, with a slight loss of efficiency. Use this if C<sv> is an expression
1710 C<SvPVutf8> is like C<SvPV>, but converts C<sv> to UTF-8 first if not already
1711 UTF-8. Similiarly, the other forms with C<utf8> in their names correspond to
1712 their respective forms without.
1714 C<SvPVutf8_or_null> and C<SvPVutf8_or_null_nomg> don't have corresponding
1715 non-C<utf8> forms. Instead they are like C<SvPVutf8_nomg>, but when C<sv> is
1716 undef, they return C<NULL>.
1718 C<SvPVbyte> is like C<SvPV>, but converts C<sv> to byte representation first if
1719 currently encoded as UTF-8. If C<sv> cannot be downgraded from UTF-8, it
1720 croaks. Similiarly, the other forms with C<byte> in their names correspond to
1721 their respective forms without.
1723 C<SvPVbyte_or_null> doesn't have a corresponding non-C<byte> form. Instead it
1724 is like C<SvPVbyte>, but when C<sv> is undef, it returns C<NULL>.
1726 =for apidoc Am|IV|SvIV|SV* sv
1727 =for apidoc_item SvIVx
1728 =for apidoc_item SvIV_nomg
1730 These coerce the given SV to IV and return it. The returned value in many
1731 circumstances will get stored in C<sv>'s IV slot, but not in all cases. (Use
1732 C<L</sv_setiv>> to make sure it does).
1734 C<SvIVx> is different from the others in that it is guaranteed to evaluate
1735 C<sv> exactly once; the others may evaluate it multiple times. Only use this
1736 form if C<sv> is an expression with side effects, otherwise use the more
1739 C<SvIV_nomg> is the same as C<SvIV>, but does not perform 'get' magic.
1741 =for apidoc Am|NV|SvNV|SV* sv
1742 =for apidoc_item SvNVx
1743 =for apidoc_item SvNV_nomg
1745 These coerce the given SV to NV and return it. The returned value in many
1746 circumstances will get stored in C<sv>'s NV slot, but not in all cases. (Use
1747 C<L</sv_setnv>> to make sure it does).
1749 C<SvNVx> is different from the others in that it is guaranteed to evaluate
1750 C<sv> exactly once; the others may evaluate it multiple times. Only use this
1751 form if C<sv> is an expression with side effects, otherwise use the more
1754 C<SvNV_nomg> is the same as C<SvNV>, but does not perform 'get' magic.
1756 =for apidoc Am|UV|SvUV|SV* sv
1757 =for apidoc_item SvUVx
1758 =for apidoc_item SvUV_nomg
1760 These coerce the given SV to UV and return it. The returned value in many
1761 circumstances will get stored in C<sv>'s UV slot, but not in all cases. (Use
1762 C<L</sv_setuv>> to make sure it does).
1764 C<SvUVx> is different from the others in that it is guaranteed to evaluate
1765 C<sv> exactly once; the others may evaluate it multiple times. Only use this
1766 form if C<sv> is an expression with side effects, otherwise use the more
1769 C<SvUV_nomg> is the same as C<SvUV>, but does not perform 'get' magic.
1772 =for apidoc_item SvTRUEx
1773 =for apidoc_item SvTRUE_nomg
1774 =for apidoc_item SvTRUE_NN
1775 =for apidoc_item SvTRUE_nomg_NN
1777 These return a boolean indicating whether Perl would evaluate the SV as true or
1778 false. See C<L</SvOK>> for a defined/undefined test.
1780 As of Perl 5.32, all are guaranteed to evaluate C<sv> only once. Prior to that
1781 release, only C<SvTRUEx> guaranteed single evaluation; now C<SvTRUEx> is
1782 identical to C<SvTRUE>.
1784 C<SvTRUE_nomg> and C<TRUE_nomg_NN> do not perform 'get' magic; the others do
1785 unless the scalar is already C<SvPOK>, C<SvIOK>, or C<SvNOK> (the public, not
1788 C<SvTRUE_NN> is like C<L</SvTRUE>>, but C<sv> is assumed to be
1789 non-null (NN). If there is a possibility that it is NULL, use plain
1792 C<SvTRUE_nomg_NN> is like C<L</SvTRUE_nomg>>, but C<sv> is assumed to be
1793 non-null (NN). If there is a possibility that it is NULL, use plain
1796 =for apidoc Am|char*|SvPVutf8_force|SV* sv|STRLEN len
1797 Like C<SvPV_force>, but converts C<sv> to UTF-8 first if necessary.
1799 =for apidoc Am|char*|SvPVutf8|SV* sv|STRLEN len
1800 Like C<SvPV>, but converts C<sv> to UTF-8 first if necessary.
1802 =for apidoc Am|char*|SvPVutf8_nomg|SV* sv|STRLEN len
1803 Like C<SvPVutf8>, but does not process get magic.
1805 =for apidoc Am|char*|SvPVutf8_or_null|SV* sv|STRLEN len
1806 Like C<SvPVutf8>, but when C<sv> is undef, returns C<NULL>.
1808 =for apidoc Am|char*|SvPVutf8_or_null_nomg|SV* sv|STRLEN len
1809 Like C<SvPVutf8_or_null>, but does not process get magic.
1811 =for apidoc Am|char*|SvPVutf8_nolen|SV* sv
1812 Like C<SvPV_nolen>, but converts C<sv> to UTF-8 first if necessary.
1814 =for apidoc Am|char*|SvPVbyte_force|SV* sv|STRLEN len
1815 Like C<SvPV_force>, but converts C<sv> to byte representation first if
1816 necessary. If the SV cannot be downgraded from UTF-8, this croaks.
1818 =for apidoc Am|char*|SvPVbyte|SV* sv|STRLEN len
1819 Like C<SvPV>, but converts C<sv> to byte representation first if necessary. If
1820 the SV cannot be downgraded from UTF-8, this croaks.
1822 =for apidoc Am|char*|SvPVbyte_nomg|SV* sv|STRLEN len
1823 Like C<SvPVbyte>, but does not process get magic.
1825 =for apidoc Am|char*|SvPVbyte_or_null|SV* sv|STRLEN len
1826 Like C<SvPVbyte>, but when C<sv> is undef, returns C<NULL>.
1828 =for apidoc Am|char*|SvPVbyte_or_null_nomg|SV* sv|STRLEN len
1829 Like C<SvPVbyte_or_null>, but does not process get magic.
1831 =for apidoc Am|char*|SvPVbyte_nolen|SV* sv
1832 Like C<SvPV_nolen>, but converts C<sv> to byte representation first if
1833 necessary. If the SV cannot be downgraded from UTF-8, this croaks.
1835 =for apidoc Am|U32|SvIsCOW|SV* sv
1836 Returns a U32 value indicating whether the SV is Copy-On-Write (either shared
1837 hash key scalars, or full Copy On Write scalars if 5.9.0 is configured for
1840 =for apidoc Am|bool|SvIsCOW_shared_hash|SV* sv
1841 Returns a boolean indicating whether the SV is Copy-On-Write shared hash key
1847 /* Let us hope that bitmaps for UV and IV are the same */
1848 #define SvIV(sv) (SvIOK_nog(sv) ? SvIVX(sv) : sv_2iv(sv))
1849 #define SvUV(sv) (SvUOK_nog(sv) ? SvUVX(sv) : sv_2uv(sv))
1850 #define SvNV(sv) (SvNOK_nog(sv) ? SvNVX(sv) : sv_2nv(sv))
1852 #define SvIV_nomg(sv) (SvIOK(sv) ? SvIVX(sv) : sv_2iv_flags(sv, 0))
1853 #define SvUV_nomg(sv) (SvUOK(sv) ? SvUVX(sv) : sv_2uv_flags(sv, 0))
1854 #define SvNV_nomg(sv) (SvNOK(sv) ? SvNVX(sv) : sv_2nv_flags(sv, 0))
1858 #define SvPV(sv, len) SvPV_flags(sv, len, SV_GMAGIC)
1859 #define SvPV_const(sv, len) SvPV_flags_const(sv, len, SV_GMAGIC)
1860 #define SvPV_mutable(sv, len) SvPV_flags_mutable(sv, len, SV_GMAGIC)
1862 /* This test is "is there a cached PV that we can use directly?"
1864 * a) SVf_POK is true and there's definitely no get magic on the scalar
1865 * b) SVp_POK is true, there's no get magic, and we know that the cached PV
1866 * came from an IV conversion.
1867 * For the latter case, we don't set SVf_POK so that we can distinguish whether
1868 * the value originated as a string or as an integer, before we cached the
1869 * second representation. */
1870 #define SvPOK_or_cached_IV(sv) \
1871 (((SvFLAGS(sv) & (SVf_POK|SVs_GMG)) == SVf_POK) || ((SvFLAGS(sv) & (SVf_IOK|SVp_POK|SVs_GMG)) == (SVf_IOK|SVp_POK)))
1873 #define SvPV_flags(sv, len, flags) \
1874 (SvPOK_or_cached_IV(sv) \
1875 ? ((len = SvCUR(sv)), SvPVX(sv)) : sv_2pv_flags(sv, &len, flags))
1876 #define SvPV_flags_const(sv, len, flags) \
1877 (SvPOK_or_cached_IV(sv) \
1878 ? ((len = SvCUR(sv)), SvPVX_const(sv)) : \
1879 (const char*) sv_2pv_flags(sv, &len, (flags|SV_CONST_RETURN)))
1880 #define SvPV_flags_const_nolen(sv, flags) \
1881 (SvPOK_or_cached_IV(sv) \
1882 ? SvPVX_const(sv) : \
1883 (const char*) sv_2pv_flags(sv, 0, (flags|SV_CONST_RETURN)))
1884 #define SvPV_flags_mutable(sv, len, flags) \
1885 (SvPOK_or_cached_IV(sv) \
1886 ? ((len = SvCUR(sv)), SvPVX_mutable(sv)) : \
1887 sv_2pv_flags(sv, &len, (flags|SV_MUTABLE_RETURN)))
1889 #define SvPV_force(sv, len) SvPV_force_flags(sv, len, SV_GMAGIC)
1890 #define SvPV_force_nolen(sv) SvPV_force_flags_nolen(sv, SV_GMAGIC)
1891 #define SvPV_force_mutable(sv, len) SvPV_force_flags_mutable(sv, len, SV_GMAGIC)
1893 #define SvPV_force_nomg(sv, len) SvPV_force_flags(sv, len, 0)
1894 #define SvPV_force_nomg_nolen(sv) SvPV_force_flags_nolen(sv, 0)
1896 #define SvPV_force_flags(sv, len, flags) \
1897 (SvPOK_pure_nogthink(sv) \
1898 ? ((len = SvCUR(sv)), SvPVX(sv)) : sv_pvn_force_flags(sv, &len, flags))
1900 #define SvPV_force_flags_nolen(sv, flags) \
1901 (SvPOK_pure_nogthink(sv) \
1902 ? SvPVX(sv) : sv_pvn_force_flags(sv, 0, flags))
1904 #define SvPV_force_flags_mutable(sv, len, flags) \
1905 (SvPOK_pure_nogthink(sv) \
1906 ? ((len = SvCUR(sv)), SvPVX_mutable(sv)) \
1907 : sv_pvn_force_flags(sv, &len, flags|SV_MUTABLE_RETURN))
1909 #define SvPV_nolen(sv) \
1910 (SvPOK_or_cached_IV(sv) \
1911 ? SvPVX(sv) : sv_2pv_flags(sv, 0, SV_GMAGIC))
1913 /* "_nomg" in these defines means no mg_get() */
1914 #define SvPV_nomg_nolen(sv) \
1915 (SvPOK_or_cached_IV(sv) \
1916 ? SvPVX(sv) : sv_2pv_flags(sv, 0, 0))
1918 #define SvPV_nolen_const(sv) \
1919 (SvPOK_or_cached_IV(sv) \
1920 ? SvPVX_const(sv) : sv_2pv_flags(sv, 0, SV_GMAGIC|SV_CONST_RETURN))
1922 #define SvPV_nomg(sv, len) SvPV_flags(sv, len, 0)
1923 #define SvPV_nomg_const(sv, len) SvPV_flags_const(sv, len, 0)
1924 #define SvPV_nomg_const_nolen(sv) SvPV_flags_const_nolen(sv, 0)
1928 #define SvPVutf8(sv, len) \
1929 (SvPOK_utf8_nog(sv) \
1930 ? ((len = SvCUR(sv)), SvPVX(sv)) : sv_2pvutf8(sv, &len))
1932 #define SvPVutf8_or_null(sv, len) \
1933 (SvPOK_utf8_nog(sv) \
1934 ? ((len = SvCUR(sv)), SvPVX(sv)) : (SvGETMAGIC(sv), SvOK(sv)) \
1935 ? sv_2pvutf8_flags(sv, &len, 0) : ((len = 0), NULL))
1937 #define SvPVutf8_nomg(sv, len) \
1938 (SvPOK_utf8_nog(sv) \
1939 ? ((len = SvCUR(sv)), SvPVX(sv)) : sv_2pvutf8_flags(sv, &len, 0))
1941 #define SvPVutf8_or_null_nomg(sv, len) \
1942 (SvPOK_utf8_nog(sv) \
1943 ? ((len = SvCUR(sv)), SvPVX(sv)) : SvOK(sv) \
1944 ? sv_2pvutf8_flags(sv, &len, 0) : ((len = 0), NULL))
1946 #define SvPVutf8_force(sv, len) \
1947 (SvPOK_utf8_pure_nogthink(sv) \
1948 ? ((len = SvCUR(sv)), SvPVX(sv)) : sv_pvutf8n_force(sv, &len))
1950 #define SvPVutf8_nolen(sv) \
1951 (SvPOK_utf8_nog(sv) \
1952 ? SvPVX(sv) : sv_2pvutf8(sv, 0))
1956 #define SvPVbyte(sv, len) \
1957 (SvPOK_byte_nog(sv) \
1958 ? ((len = SvCUR(sv)), SvPVX(sv)) : sv_2pvbyte(sv, &len))
1960 #define SvPVbyte_or_null(sv, len) \
1961 (SvPOK_byte_nog(sv) \
1962 ? ((len = SvCUR(sv)), SvPVX(sv)) : (SvGETMAGIC(sv), SvOK(sv)) \
1963 ? sv_2pvbyte_flags(sv, &len, 0) : ((len = 0), NULL))
1965 #define SvPVbyte_nomg(sv, len) \
1966 (SvPOK_byte_nog(sv) \
1967 ? ((len = SvCUR(sv)), SvPVX(sv)) : sv_2pvbyte_flags(sv, &len, 0))
1969 #define SvPVbyte_or_null_nomg(sv, len) \
1970 (SvPOK_utf8_nog(sv) \
1971 ? ((len = SvCUR(sv)), SvPVX(sv)) : SvOK(sv) \
1972 ? sv_2pvbyte_flags(sv, &len, 0) : ((len = 0), NULL))
1974 #define SvPVbyte_force(sv, len) \
1975 (SvPOK_byte_pure_nogthink(sv) \
1976 ? ((len = SvCUR(sv)), SvPVX(sv)) : sv_pvbyten_force(sv, &len))
1978 #define SvPVbyte_nolen(sv) \
1979 (SvPOK_byte_nog(sv) \
1980 ? SvPVX(sv) : sv_2pvbyte(sv, 0))
1983 /* define FOOx(): idempotent versions of FOO(). If possible, use a local
1984 * var to evaluate the arg once; failing that, use a global if possible;
1985 * failing that, call a function to do the work
1988 #define SvPVx_force(sv, len) sv_pvn_force(sv, &len)
1989 #define SvPVutf8x_force(sv, len) sv_pvutf8n_force(sv, &len)
1990 #define SvPVbytex_force(sv, len) sv_pvbyten_force(sv, &len)
1992 #define SvTRUEx(sv) SvTRUE(sv)
1993 #define SvTRUEx_nomg(sv) SvTRUE_nomg(sv)
1994 #define SvTRUE_nomg_NN(sv) SvTRUE_common(sv, TRUE)
1996 #if defined(PERL_USE_GCC_BRACE_GROUPS)
1998 # define SvIVx(sv) ({SV *_sv = MUTABLE_SV(sv); SvIV(_sv); })
1999 # define SvUVx(sv) ({SV *_sv = MUTABLE_SV(sv); SvUV(_sv); })
2000 # define SvNVx(sv) ({SV *_sv = MUTABLE_SV(sv); SvNV(_sv); })
2001 # define SvPVx(sv, len) ({SV *_sv = (sv); SvPV(_sv, len); })
2002 # define SvPVx_const(sv, len) ({SV *_sv = (sv); SvPV_const(_sv, len); })
2003 # define SvPVx_nolen(sv) ({SV *_sv = (sv); SvPV_nolen(_sv); })
2004 # define SvPVx_nolen_const(sv) ({SV *_sv = (sv); SvPV_nolen_const(_sv); })
2005 # define SvPVutf8x(sv, len) ({SV *_sv = (sv); SvPVutf8(_sv, len); })
2006 # define SvPVbytex(sv, len) ({SV *_sv = (sv); SvPVbyte(_sv, len); })
2007 # define SvPVbytex_nolen(sv) ({SV *_sv = (sv); SvPVbyte_nolen(_sv); })
2009 #else /* __GNUC__ */
2011 /* These inlined macros use globals, which will require a thread
2012 * declaration in user code, so we avoid them under threads */
2014 # define SvIVx(sv) ((PL_Sv = (sv)), SvIV(PL_Sv))
2015 # define SvUVx(sv) ((PL_Sv = (sv)), SvUV(PL_Sv))
2016 # define SvNVx(sv) ((PL_Sv = (sv)), SvNV(PL_Sv))
2017 # define SvPVx(sv, len) ((PL_Sv = (sv)), SvPV(PL_Sv, len))
2018 # define SvPVx_const(sv, len) ((PL_Sv = (sv)), SvPV_const(PL_Sv, len))
2019 # define SvPVx_nolen(sv) ((PL_Sv = (sv)), SvPV_nolen(PL_Sv))
2020 # define SvPVx_nolen_const(sv) ((PL_Sv = (sv)), SvPV_nolen_const(PL_Sv))
2021 # define SvPVutf8x(sv, len) ((PL_Sv = (sv)), SvPVutf8(PL_Sv, len))
2022 # define SvPVbytex(sv, len) ((PL_Sv = (sv)), SvPVbyte(PL_Sv, len))
2023 # define SvPVbytex_nolen(sv) ((PL_Sv = (sv)), SvPVbyte_nolen(PL_Sv))
2024 #endif /* __GNU__ */
2026 #define SvPVXtrue(sv) ( \
2027 ((XPV*)SvANY((sv))) \
2029 ((XPV*)SvANY((sv)))->xpv_cur > 1 \
2031 ((XPV*)SvANY((sv)))->xpv_cur \
2032 && *(sv)->sv_u.svu_pv != '0' \
2037 #define SvIsCOW(sv) (SvFLAGS(sv) & SVf_IsCOW)
2038 #define SvIsCOW_on(sv) (SvFLAGS(sv) |= SVf_IsCOW)
2039 #define SvIsCOW_off(sv) (SvFLAGS(sv) &= ~(SVf_IsCOW|SVppv_STATIC))
2040 #define SvIsCOW_shared_hash(sv) ((SvFLAGS(sv) & (SVf_IsCOW|SVppv_STATIC)) == (SVf_IsCOW) && SvLEN(sv) == 0)
2041 #define SvIsCOW_static(sv) ((SvFLAGS(sv) & (SVf_IsCOW|SVppv_STATIC)) == (SVf_IsCOW|SVppv_STATIC))
2043 #define SvSHARED_HEK_FROM_PV(pvx) \
2044 ((struct hek*)(pvx - STRUCT_OFFSET(struct hek, hek_key)))
2046 =for apidoc Am|struct hek*|SvSHARED_HASH|SV * sv
2047 Returns the hash for C<sv> created by C<L</newSVpvn_share>>.
2051 #define SvSHARED_HASH(sv) (0 + SvSHARED_HEK_FROM_PV(SvPVX_const(sv))->hek_hash)
2053 /* flag values for sv_*_flags functions */
2054 #define SV_UTF8_NO_ENCODING 0 /* No longer used */
2057 =for apidoc AmnhD||SV_UTF8_NO_ENCODING
2062 #define SV_IMMEDIATE_UNREF 1
2064 #define SV_COW_DROP_PV 4
2065 #define SV_NOSTEAL 16
2066 #define SV_CONST_RETURN 32
2067 #define SV_MUTABLE_RETURN 64
2068 #define SV_SMAGIC 128
2069 #define SV_HAS_TRAILING_NUL 256
2070 #define SV_COW_SHARED_HASH_KEYS 512
2071 /* This one is only enabled for PERL_OLD_COPY_ON_WRITE */
2072 /* XXX This flag actually enabled for any COW. But it appears not to do
2073 anything. Can we just remove it? Or will it serve some future
2075 #define SV_COW_OTHER_PVS 1024
2076 /* Make sv_2pv_flags return NULL if something is undefined. */
2077 #define SV_UNDEF_RETURNS_NULL 2048
2078 /* Tell sv_utf8_upgrade() to not check to see if an upgrade is really needed.
2079 * This is used when the caller has already determined it is, and avoids
2081 #define SV_FORCE_UTF8_UPGRADE 4096
2082 /* if (after resolving magic etc), the SV is found to be overloaded,
2083 * don't call the overload magic, just return as-is */
2084 #define SV_SKIP_OVERLOAD 8192
2085 #define SV_CATBYTES 16384
2086 #define SV_CATUTF8 32768
2088 /* The core is safe for this COW optimisation. XS code on CPAN may not be.
2089 So only default to doing the COW setup if we're in the core.
2092 # ifndef SV_DO_COW_SVSETSV
2093 # define SV_DO_COW_SVSETSV SV_COW_SHARED_HASH_KEYS|SV_COW_OTHER_PVS
2097 #ifndef SV_DO_COW_SVSETSV
2098 # define SV_DO_COW_SVSETSV 0
2102 #define sv_unref(sv) sv_unref_flags(sv, 0)
2103 #define sv_force_normal(sv) sv_force_normal_flags(sv, 0)
2104 #define sv_usepvn(sv, p, l) sv_usepvn_flags(sv, p, l, 0)
2105 #define sv_usepvn_mg(sv, p, l) sv_usepvn_flags(sv, p, l, SV_SMAGIC)
2107 /* We are about to replace the SV's current value. So if it's copy on write
2108 we need to normalise it. Use the SV_COW_DROP_PV flag hint to say that
2109 the value is about to get thrown away, so drop the PV rather than go to
2110 the effort of making a read-write copy only for it to get immediately
2113 #define SV_CHECK_THINKFIRST_COW_DROP(sv) if (SvTHINKFIRST(sv)) \
2114 sv_force_normal_flags(sv, SV_COW_DROP_PV)
2116 #ifdef PERL_COPY_ON_WRITE
2117 # define SvCANCOW(sv) \
2119 ? SvLEN(sv) ? CowREFCNT(sv) != SV_COW_REFCNT_MAX : 1 \
2120 : (SvFLAGS(sv) & CAN_COW_MASK) == CAN_COW_FLAGS \
2121 && SvCUR(sv)+1 < SvLEN(sv))
2122 /* Note: To allow 256 COW "copies", a refcnt of 0 means 1. */
2123 # define CowREFCNT(sv) (*(U8 *)(SvPVX(sv)+SvLEN(sv)-1))
2124 # define SV_COW_REFCNT_MAX nBIT_UMAX(sizeof(U8) * CHARBITS)
2125 # define CAN_COW_MASK (SVf_POK|SVf_ROK|SVp_POK|SVf_FAKE| \
2126 SVf_OOK|SVf_BREAK|SVf_READONLY|SVf_PROTECT)
2129 #define CAN_COW_FLAGS (SVp_POK|SVf_POK)
2131 #define SV_CHECK_THINKFIRST(sv) if (SvTHINKFIRST(sv)) \
2132 sv_force_normal_flags(sv, 0)
2135 /* all these 'functions' are now just macros */
2137 #define sv_pv(sv) SvPV_nolen(sv)
2138 #define sv_pvutf8(sv) SvPVutf8_nolen(sv)
2139 #define sv_pvbyte(sv) SvPVbyte_nolen(sv)
2141 #define sv_pvn_force_nomg(sv, lp) sv_pvn_force_flags(sv, lp, 0)
2142 #define sv_utf8_upgrade_flags(sv, flags) sv_utf8_upgrade_flags_grow(sv, flags, 0)
2143 #define sv_utf8_upgrade_nomg(sv) sv_utf8_upgrade_flags(sv, 0)
2144 #define sv_utf8_downgrade(sv, fail_ok) sv_utf8_downgrade_flags(sv, fail_ok, SV_GMAGIC)
2145 #define sv_utf8_downgrade_nomg(sv, fail_ok) sv_utf8_downgrade_flags(sv, fail_ok, 0)
2146 #define sv_catpvn_nomg(dsv, sstr, slen) sv_catpvn_flags(dsv, sstr, slen, 0)
2147 #define sv_catpv_nomg(dsv, sstr) sv_catpv_flags(dsv, sstr, 0)
2148 #define sv_setsv(dsv, ssv) \
2149 sv_setsv_flags(dsv, ssv, SV_GMAGIC|SV_DO_COW_SVSETSV)
2150 #define sv_setsv_nomg(dsv, ssv) sv_setsv_flags(dsv, ssv, SV_DO_COW_SVSETSV)
2151 #define sv_catsv(dsv, ssv) sv_catsv_flags(dsv, ssv, SV_GMAGIC)
2152 #define sv_catsv_nomg(dsv, ssv) sv_catsv_flags(dsv, ssv, 0)
2153 #define sv_catsv_mg(dsv, ssv) sv_catsv_flags(dsv, ssv, SV_GMAGIC|SV_SMAGIC)
2154 #define sv_catpvn(dsv, sstr, slen) sv_catpvn_flags(dsv, sstr, slen, SV_GMAGIC)
2155 #define sv_catpvn_mg(dsv, sstr, slen) sv_catpvn_flags(dsv, sstr, slen, SV_GMAGIC|SV_SMAGIC);
2156 #define sv_copypv(dsv, ssv) sv_copypv_flags(dsv, ssv, SV_GMAGIC)
2157 #define sv_copypv_nomg(dsv, ssv) sv_copypv_flags(dsv, ssv, 0)
2158 #define sv_2pv(sv, lp) sv_2pv_flags(sv, lp, SV_GMAGIC)
2159 #define sv_2pv_nolen(sv) sv_2pv(sv, 0)
2160 #define sv_2pvbyte(sv, lp) sv_2pvbyte_flags(sv, lp, SV_GMAGIC)
2161 #define sv_2pvbyte_nolen(sv) sv_2pvbyte(sv, 0)
2162 #define sv_2pvutf8(sv, lp) sv_2pvutf8_flags(sv, lp, SV_GMAGIC)
2163 #define sv_2pvutf8_nolen(sv) sv_2pvutf8(sv, 0)
2164 #define sv_2pv_nomg(sv, lp) sv_2pv_flags(sv, lp, 0)
2165 #define sv_pvn_force(sv, lp) sv_pvn_force_flags(sv, lp, SV_GMAGIC)
2166 #define sv_utf8_upgrade(sv) sv_utf8_upgrade_flags(sv, SV_GMAGIC)
2167 #define sv_2iv(sv) sv_2iv_flags(sv, SV_GMAGIC)
2168 #define sv_2uv(sv) sv_2uv_flags(sv, SV_GMAGIC)
2169 #define sv_2nv(sv) sv_2nv_flags(sv, SV_GMAGIC)
2170 #define sv_eq(sv1, sv2) sv_eq_flags(sv1, sv2, SV_GMAGIC)
2171 #define sv_cmp(sv1, sv2) sv_cmp_flags(sv1, sv2, SV_GMAGIC)
2172 #define sv_cmp_locale(sv1, sv2) sv_cmp_locale_flags(sv1, sv2, SV_GMAGIC)
2173 #define sv_numeq(sv1, sv2) sv_numeq_flags(sv1, sv2, SV_GMAGIC)
2174 #define sv_streq(sv1, sv2) sv_streq_flags(sv1, sv2, SV_GMAGIC)
2175 #define sv_collxfrm(sv, nxp) sv_collxfrm_flags(sv, nxp, SV_GMAGIC)
2176 #define sv_2bool(sv) sv_2bool_flags(sv, SV_GMAGIC)
2177 #define sv_2bool_nomg(sv) sv_2bool_flags(sv, 0)
2178 #define sv_insert(bigstr, offset, len, little, littlelen) \
2179 Perl_sv_insert_flags(aTHX_ (bigstr),(offset), (len), (little), \
2180 (littlelen), SV_GMAGIC)
2181 #define sv_mortalcopy(sv) \
2182 Perl_sv_mortalcopy_flags(aTHX_ sv, SV_GMAGIC|SV_DO_COW_SVSETSV)
2183 #define sv_cathek(sv,hek) \
2185 HEK * const bmxk = hek; \
2186 sv_catpvn_flags(sv, HEK_KEY(bmxk), HEK_LEN(bmxk), \
2187 HEK_UTF8(bmxk) ? SV_CATUTF8 : SV_CATBYTES); \
2190 /* Should be named SvCatPVN_utf8_upgrade? */
2191 #define sv_catpvn_nomg_utf8_upgrade(dsv, sstr, slen, nsv) \
2194 nsv = newSVpvn_flags(sstr, slen, SVs_TEMP); \
2196 sv_setpvn(nsv, sstr, slen); \
2198 sv_utf8_upgrade(nsv); \
2199 sv_catsv_nomg(dsv, nsv); \
2201 #define sv_catpvn_nomg_maybeutf8(dsv, sstr, slen, is_utf8) \
2202 sv_catpvn_flags(dsv, sstr, slen, (is_utf8)?SV_CATUTF8:SV_CATBYTES)
2204 #if defined(PERL_CORE) || defined(PERL_EXT)
2205 # define sv_or_pv_len_utf8(sv, pv, bytelen) \
2207 ? utf8_length((U8 *)(pv), (U8 *)(pv)+(bytelen)) \
2213 =for apidoc_item ||newRV_inc|
2215 These are identical. They create an RV wrapper for an SV. The reference count
2216 for the original SV is incremented.
2221 #define newRV_inc(sv) newRV(sv)
2223 /* the following macros update any magic values this C<sv> is associated with */
2226 =for apidoc_section $SV
2228 =for apidoc Am|void|SvGETMAGIC|SV* sv
2229 Invokes C<L</mg_get>> on an SV if it has 'get' magic. For example, this
2230 will call C<FETCH> on a tied variable. This macro evaluates its
2231 argument more than once.
2233 =for apidoc Am|void|SvSETMAGIC|SV* sv
2234 Invokes C<L</mg_set>> on an SV if it has 'set' magic. This is necessary
2235 after modifying a scalar, in case it is a magical variable like C<$|>
2236 or a tied variable (it calls C<STORE>). This macro evaluates its
2237 argument more than once.
2239 =for apidoc Am|void|SvSetSV|SV* dsv|SV* ssv
2240 =for apidoc_item SvSetMagicSV
2241 =for apidoc_item SvSetSV_nosteal
2242 =for apidoc_item SvSetMagicSV_nosteal
2244 if C<dsv> is the same as C<ssv>, these do nothing. Otherwise they all call
2245 some form of C<L</sv_setsv>>. They may evaluate their arguments more than
2248 The only differences are:
2250 C<SvSetMagicSV> and C<SvSetMagicSV_nosteal> perform any required 'set' magic
2251 afterwards on the destination SV; C<SvSetSV> and C<SvSetSV_nosteal> do not.
2253 C<SvSetSV_nosteal> C<SvSetMagicSV_nosteal> call a non-destructive version of
2256 =for apidoc Am|void|SvSHARE|SV* sv
2257 Arranges for C<sv> to be shared between threads if a suitable module
2260 =for apidoc Am|void|SvLOCK|SV* sv
2261 Arranges for a mutual exclusion lock to be obtained on C<sv> if a suitable module
2264 =for apidoc Am|void|SvUNLOCK|SV* sv
2265 Releases a mutual exclusion lock on C<sv> if a suitable module
2268 =for apidoc_section $SV
2270 =for apidoc Am|char *|SvGROW|SV* sv|STRLEN len
2271 Expands the character buffer in the SV so that it has room for the
2272 indicated number of bytes (remember to reserve space for an extra trailing
2273 C<NUL> character). Calls C<sv_grow> to perform the expansion if necessary.
2274 Returns a pointer to the character
2275 buffer. SV must be of type >= C<SVt_PV>. One
2276 alternative is to call C<sv_grow> if you are not sure of the type of SV.
2278 You might mistakenly think that C<len> is the number of bytes to add to the
2279 existing size, but instead it is the total size C<sv> should be.
2281 =for apidoc Am|char *|SvPVCLEAR|SV* sv
2282 Ensures that sv is a SVt_PV and that its SvCUR is 0, and that it is
2283 properly null terminated. Equivalent to sv_setpvs(""), but more efficient.
2288 #define SvPVCLEAR(sv) sv_setpv_bufsize(sv,0,0)
2289 #define SvSHARE(sv) PL_sharehook(aTHX_ sv)
2290 #define SvLOCK(sv) PL_lockhook(aTHX_ sv)
2291 #define SvUNLOCK(sv) PL_unlockhook(aTHX_ sv)
2292 #define SvDESTROYABLE(sv) PL_destroyhook(aTHX_ sv)
2294 #define SvGETMAGIC(x) ((void)(UNLIKELY(SvGMAGICAL(x)) && mg_get(x)))
2295 #define SvSETMAGIC(x) STMT_START { if (UNLIKELY(SvSMAGICAL(x))) mg_set(x); } STMT_END
2297 #define SvSetSV_and(dst,src,finally) \
2299 if (LIKELY((dst) != (src))) { \
2300 sv_setsv(dst, src); \
2304 #define SvSetSV_nosteal_and(dst,src,finally) \
2306 if (LIKELY((dst) != (src))) { \
2307 sv_setsv_flags(dst, src, SV_GMAGIC | SV_NOSTEAL | SV_DO_COW_SVSETSV); \
2312 #define SvSetSV(dst,src) \
2313 SvSetSV_and(dst,src,/*nothing*/;)
2314 #define SvSetSV_nosteal(dst,src) \
2315 SvSetSV_nosteal_and(dst,src,/*nothing*/;)
2317 #define SvSetMagicSV(dst,src) \
2318 SvSetSV_and(dst,src,SvSETMAGIC(dst))
2319 #define SvSetMagicSV_nosteal(dst,src) \
2320 SvSetSV_nosteal_and(dst,src,SvSETMAGIC(dst))
2323 #if !defined(SKIP_DEBUGGING)
2324 #define SvPEEK(sv) sv_peek(sv)
2326 #define SvPEEK(sv) ""
2329 /* Is this a per-interpreter immortal SV (rather than global)?
2330 * These should either occupy adjacent entries in the interpreter struct
2331 * (MULTIPLICITY) or adjacent elements of PL_sv_immortals[] otherwise.
2332 * The unsigned (Size_t) cast avoids the need for a second < 0 condition.
2334 #define SvIMMORTAL_INTERP(sv) ((Size_t)((sv) - &PL_sv_yes) < 4)
2336 /* Does this immortal have a true value? Currently only PL_sv_yes does. */
2337 #define SvIMMORTAL_TRUE(sv) ((sv) == &PL_sv_yes)
2339 /* the SvREADONLY() test is to quickly reject most SVs */
2340 #define SvIMMORTAL(sv) \
2342 && (SvIMMORTAL_INTERP(sv) || (sv) == &PL_sv_placeholder))
2345 /* exercise the immortal resurrection code in sv_free2() */
2346 # define SvREFCNT_IMMORTAL 1000
2348 # define SvREFCNT_IMMORTAL ((~(U32)0)/2)
2352 =for apidoc Am|SV *|boolSV|bool b
2354 Returns a true SV if C<b> is a true value, or a false SV if C<b> is 0.
2356 See also C<L</PL_sv_yes>> and C<L</PL_sv_no>>.
2361 #define boolSV(b) ((b) ? &PL_sv_yes : &PL_sv_no)
2364 =for apidoc Am|void|sv_setbool|SV *sv|bool b
2365 =for apidoc_item |void|sv_setbool_mg|SV *sv|bool b
2367 These set an SV to a true or false boolean value, upgrading first if necessary.
2369 They differ only in that C<sv_setbool_mg> handles 'set' magic; C<sv_setbool>
2375 #define sv_setbool(sv, b) sv_setsv(sv, boolSV(b))
2376 #define sv_setbool_mg(sv, b) sv_setsv_mg(sv, boolSV(b))
2378 #define isGV(sv) (SvTYPE(sv) == SVt_PVGV)
2379 /* If I give every macro argument a different name, then there won't be bugs
2380 where nested macros get confused. Been there, done that. */
2382 =for apidoc Am|bool|isGV_with_GP|SV * sv
2383 Returns a boolean as to whether or not C<sv> is a GV with a pointer to a GP
2388 #define isGV_with_GP(pwadak) \
2389 (((SvFLAGS(pwadak) & (SVp_POK|SVpgv_GP)) == SVpgv_GP) \
2390 && (SvTYPE(pwadak) == SVt_PVGV || SvTYPE(pwadak) == SVt_PVLV))
2391 #define isGV_with_GP_on(sv) STMT_START { \
2392 assert (SvTYPE(sv) == SVt_PVGV || SvTYPE(sv) == SVt_PVLV); \
2393 assert (!SvPOKp(sv)); \
2394 assert (!SvIOKp(sv)); \
2395 (SvFLAGS(sv) |= SVpgv_GP); \
2397 #define isGV_with_GP_off(sv) STMT_START { \
2398 assert (SvTYPE(sv) == SVt_PVGV || SvTYPE(sv) == SVt_PVLV); \
2399 assert (!SvPOKp(sv)); \
2400 assert (!SvIOKp(sv)); \
2401 (SvFLAGS(sv) &= ~SVpgv_GP); \
2404 # define isGV_or_RVCV(kadawp) \
2405 (isGV(kadawp) || (SvROK(kadawp) && SvTYPE(SvRV(kadawp)) == SVt_PVCV))
2407 #define isREGEXP(sv) \
2408 (SvTYPE(sv) == SVt_REGEXP \
2409 || (SvFLAGS(sv) & (SVTYPEMASK|SVpgv_GP|SVf_FAKE)) \
2410 == (SVt_PVLV|SVf_FAKE))
2414 # define SvGROW(sv,len) \
2415 (SvIsCOW(sv) || SvLEN(sv) < (len) ? sv_grow(sv,len) : SvPVX(sv))
2417 # define SvGROW(sv,len) (SvLEN(sv) < (len) ? sv_grow(sv,len) : SvPVX(sv))
2419 #define SvGROW_mutable(sv,len) \
2420 (SvLEN(sv) < (len) ? sv_grow(sv,len) : SvPVX_mutable(sv))
2421 #define Sv_Grow sv_grow
2423 #define CLONEf_COPY_STACKS 1
2424 #define CLONEf_KEEP_PTR_TABLE 2
2425 #define CLONEf_CLONE_HOST 4
2426 #define CLONEf_JOIN_IN 8
2428 struct clone_params {
2431 PerlInterpreter *proto_perl;
2432 PerlInterpreter *new_perl;
2436 /* SV_NOSTEAL prevents TEMP buffers being, well, stolen, and saves games
2437 with SvTEMP_off and SvTEMP_on round a call to sv_setsv. */
2438 #define newSVsv(sv) newSVsv_flags((sv), SV_GMAGIC|SV_NOSTEAL)
2439 #define newSVsv_nomg(sv) newSVsv_flags((sv), SV_NOSTEAL)
2442 =for apidoc Am|SV*|newSVpvn_utf8|const char* s|STRLEN len|U32 utf8
2444 Creates a new SV and copies a string (which may contain C<NUL> (C<\0>)
2445 characters) into it. If C<utf8> is true, calls
2446 C<SvUTF8_on> on the new SV. Implemented as a wrapper around C<newSVpvn_flags>.
2451 #define newSVpvn_utf8(s, len, u) newSVpvn_flags((s), (len), (u) ? SVf_UTF8 : 0)
2454 =for apidoc Amx|SV*|newSVpadname|PADNAME *pn
2456 Creates a new SV containing the pad name.
2461 #define newSVpadname(pn) newSVpvn_utf8(PadnamePV(pn), PadnameLEN(pn), TRUE)
2464 =for apidoc Am|void|SvOOK_offset|SV*sv|STRLEN len
2466 Reads into C<len> the offset from C<SvPVX> back to the true start of the
2467 allocated buffer, which will be non-zero if C<sv_chop> has been used to
2468 efficiently remove characters from start of the buffer. Implemented as a
2469 macro, which takes the address of C<len>, which must be of type C<STRLEN>.
2470 Evaluates C<sv> more than once. Sets C<len> to 0 if C<SvOOK(sv)> is false.
2476 /* Does the bot know something I don't?
2477 10:28 <@Nicholas> metabatman
2478 10:28 <+meta> Nicholas: crash
2480 # define SvOOK_offset(sv, offset) STMT_START { \
2481 STATIC_ASSERT_STMT(sizeof(offset) == sizeof(STRLEN)); \
2483 const U8 *_crash = (U8*)SvPVX_const(sv); \
2484 (offset) = *--_crash; \
2486 _crash -= sizeof(STRLEN); \
2487 Copy(_crash, (U8 *)&(offset), sizeof(STRLEN), U8); \
2490 /* Validate the preceding buffer's sentinels to \
2491 verify that no-one is using it. */ \
2492 const U8 *const _bonk = (U8*)SvPVX_const(sv) - (offset);\
2493 while (_crash > _bonk) { \
2495 assert (*_crash == (U8)PTR2UV(_crash)); \
2503 /* This is the same code, but avoids using any temporary variables: */
2504 # define SvOOK_offset(sv, offset) STMT_START { \
2505 STATIC_ASSERT_STMT(sizeof(offset) == sizeof(STRLEN)); \
2507 (offset) = ((U8*)SvPVX_const(sv))[-1]; \
2509 Copy(SvPVX_const(sv) - 1 - sizeof(STRLEN), \
2510 (U8*)&(offset), sizeof(STRLEN), U8); \
2518 #define newIO() MUTABLE_IO(newSV_type(SVt_PVIO))
2520 #if defined(PERL_CORE) || defined(PERL_EXT)
2522 # define SV_CONST(name) \
2523 PL_sv_consts[SV_CONST_##name] \
2524 ? PL_sv_consts[SV_CONST_##name] \
2525 : (PL_sv_consts[SV_CONST_##name] = newSVpv_share(#name, 0))
2527 # define SV_CONST_TIESCALAR 0
2528 # define SV_CONST_TIEARRAY 1
2529 # define SV_CONST_TIEHASH 2
2530 # define SV_CONST_TIEHANDLE 3
2532 # define SV_CONST_FETCH 4
2533 # define SV_CONST_FETCHSIZE 5
2534 # define SV_CONST_STORE 6
2535 # define SV_CONST_STORESIZE 7
2536 # define SV_CONST_EXISTS 8
2538 # define SV_CONST_PUSH 9
2539 # define SV_CONST_POP 10
2540 # define SV_CONST_SHIFT 11
2541 # define SV_CONST_UNSHIFT 12
2542 # define SV_CONST_SPLICE 13
2543 # define SV_CONST_EXTEND 14
2545 # define SV_CONST_FIRSTKEY 15
2546 # define SV_CONST_NEXTKEY 16
2547 # define SV_CONST_SCALAR 17
2549 # define SV_CONST_OPEN 18
2550 # define SV_CONST_WRITE 19
2551 # define SV_CONST_PRINT 20
2552 # define SV_CONST_PRINTF 21
2553 # define SV_CONST_READ 22
2554 # define SV_CONST_READLINE 23
2555 # define SV_CONST_GETC 24
2556 # define SV_CONST_SEEK 25
2557 # define SV_CONST_TELL 26
2558 # define SV_CONST_EOF 27
2559 # define SV_CONST_BINMODE 28
2560 # define SV_CONST_FILENO 29
2561 # define SV_CONST_CLOSE 30
2563 # define SV_CONST_DELETE 31
2564 # define SV_CONST_CLEAR 32
2565 # define SV_CONST_UNTIE 33
2566 # define SV_CONST_DESTROY 34
2569 #define SV_CONSTS_COUNT 35
2572 * Bodyless IVs and NVs!
2574 * Since 5.9.2, we can avoid allocating a body for SVt_IV-type SVs.
2575 * Since the larger IV-holding variants of SVs store their integer
2576 * values in their respective bodies, the family of SvIV() accessor
2577 * macros would naively have to branch on the SV type to find the
2578 * integer value either in the HEAD or BODY. In order to avoid this
2579 * expensive branch, a clever soul has deployed a great hack:
2580 * We set up the SvANY pointer such that instead of pointing to a
2581 * real body, it points into the memory before the location of the
2582 * head. We compute this pointer such that the location of
2583 * the integer member of the hypothetical body struct happens to
2584 * be the same as the location of the integer member of the bodyless
2585 * SV head. This now means that the SvIV() family of accessors can
2586 * always read from the (hypothetical or real) body via SvANY.
2588 * Since the 5.21 dev series, we employ the same trick for NVs
2589 * if the architecture can support it (NVSIZE <= IVSIZE).
2592 /* The following two macros compute the necessary offsets for the above
2593 * trick and store them in SvANY for SvIV() (and friends) to use. */
2596 # define SET_SVANY_FOR_BODYLESS_IV(sv) \
2597 SvANY(sv) = (XPVIV*)((char*)&(sv->sv_u.svu_iv) \
2598 - STRUCT_OFFSET(XPVIV, xiv_iv))
2600 # define SET_SVANY_FOR_BODYLESS_NV(sv) \
2601 SvANY(sv) = (XPVNV*)((char*)&(sv->sv_u.svu_nv) \
2602 - STRUCT_OFFSET(XPVNV, xnv_u.xnv_nv))
2606 * ex: set ts=8 sts=4 sw=4 et: