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a0d0e21e 1/* sv.c
79072805 2 *
4bb101f2 3 * Copyright (C) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
7272f7c1 4 * 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, by Larry Wall and others
79072805
LW
5 *
6 * You may distribute under the terms of either the GNU General Public
7 * License or the Artistic License, as specified in the README file.
8 *
a0d0e21e 9 * "I wonder what the Entish is for 'yes' and 'no'," he thought.
645c22ef
DM
10 *
11 *
5e045b90
AMS
12 * This file contains the code that creates, manipulates and destroys
13 * scalar values (SVs). The other types (AV, HV, GV, etc.) reuse the
14 * structure of an SV, so their creation and destruction is handled
15 * here; higher-level functions are in av.c, hv.c, and so on. Opcode
16 * level functions (eg. substr, split, join) for each of the types are
17 * in the pp*.c files.
79072805
LW
18 */
19
20#include "EXTERN.h"
864dbfa3 21#define PERL_IN_SV_C
79072805 22#include "perl.h"
d2f185dc 23#include "regcomp.h"
79072805 24
51371543 25#define FCALL *f
2c5424a7 26
2f8ed50e
OS
27#ifdef __Lynx__
28/* Missing proto on LynxOS */
29 char *gconvert(double, int, int, char *);
30#endif
31
e23c8137 32#ifdef PERL_UTF8_CACHE_ASSERT
ab455f60 33/* if adding more checks watch out for the following tests:
e23c8137
JH
34 * t/op/index.t t/op/length.t t/op/pat.t t/op/substr.t
35 * lib/utf8.t lib/Unicode/Collate/t/index.t
36 * --jhi
37 */
6f207bd3 38# define ASSERT_UTF8_CACHE(cache) \
ab455f60
NC
39 STMT_START { if (cache) { assert((cache)[0] <= (cache)[1]); \
40 assert((cache)[2] <= (cache)[3]); \
41 assert((cache)[3] <= (cache)[1]);} \
42 } STMT_END
e23c8137 43#else
6f207bd3 44# define ASSERT_UTF8_CACHE(cache) NOOP
e23c8137
JH
45#endif
46
f8c7b90f 47#ifdef PERL_OLD_COPY_ON_WRITE
765f542d 48#define SV_COW_NEXT_SV(sv) INT2PTR(SV *,SvUVX(sv))
607fa7f2 49#define SV_COW_NEXT_SV_SET(current,next) SvUV_set(current, PTR2UV(next))
b5ccf5f2 50/* This is a pessimistic view. Scalar must be purely a read-write PV to copy-
765f542d 51 on-write. */
765f542d 52#endif
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DM
53
54/* ============================================================================
55
56=head1 Allocation and deallocation of SVs.
57
d2a0f284
JC
58An SV (or AV, HV, etc.) is allocated in two parts: the head (struct
59sv, av, hv...) contains type and reference count information, and for
60many types, a pointer to the body (struct xrv, xpv, xpviv...), which
61contains fields specific to each type. Some types store all they need
62in the head, so don't have a body.
63
64In all but the most memory-paranoid configuations (ex: PURIFY), heads
65and bodies are allocated out of arenas, which by default are
66approximately 4K chunks of memory parcelled up into N heads or bodies.
93e68bfb
JC
67Sv-bodies are allocated by their sv-type, guaranteeing size
68consistency needed to allocate safely from arrays.
69
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JC
70For SV-heads, the first slot in each arena is reserved, and holds a
71link to the next arena, some flags, and a note of the number of slots.
72Snaked through each arena chain is a linked list of free items; when
73this becomes empty, an extra arena is allocated and divided up into N
74items which are threaded into the free list.
75
76SV-bodies are similar, but they use arena-sets by default, which
77separate the link and info from the arena itself, and reclaim the 1st
78slot in the arena. SV-bodies are further described later.
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79
80The following global variables are associated with arenas:
81
82 PL_sv_arenaroot pointer to list of SV arenas
83 PL_sv_root pointer to list of free SV structures
84
d2a0f284
JC
85 PL_body_arenas head of linked-list of body arenas
86 PL_body_roots[] array of pointers to list of free bodies of svtype
87 arrays are indexed by the svtype needed
93e68bfb 88
d2a0f284
JC
89A few special SV heads are not allocated from an arena, but are
90instead directly created in the interpreter structure, eg PL_sv_undef.
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91The size of arenas can be changed from the default by setting
92PERL_ARENA_SIZE appropriately at compile time.
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93
94The SV arena serves the secondary purpose of allowing still-live SVs
95to be located and destroyed during final cleanup.
96
97At the lowest level, the macros new_SV() and del_SV() grab and free
98an SV head. (If debugging with -DD, del_SV() calls the function S_del_sv()
99to return the SV to the free list with error checking.) new_SV() calls
100more_sv() / sv_add_arena() to add an extra arena if the free list is empty.
101SVs in the free list have their SvTYPE field set to all ones.
102
ff276b08 103At the time of very final cleanup, sv_free_arenas() is called from
645c22ef 104perl_destruct() to physically free all the arenas allocated since the
6a93a7e5 105start of the interpreter.
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106
107Manipulation of any of the PL_*root pointers is protected by enclosing
108LOCK_SV_MUTEX; ... UNLOCK_SV_MUTEX calls which should Do the Right Thing
109if threads are enabled.
110
111The function visit() scans the SV arenas list, and calls a specified
112function for each SV it finds which is still live - ie which has an SvTYPE
113other than all 1's, and a non-zero SvREFCNT. visit() is used by the
114following functions (specified as [function that calls visit()] / [function
115called by visit() for each SV]):
116
117 sv_report_used() / do_report_used()
f2524eef 118 dump all remaining SVs (debugging aid)
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119
120 sv_clean_objs() / do_clean_objs(),do_clean_named_objs()
121 Attempt to free all objects pointed to by RVs,
122 and, unless DISABLE_DESTRUCTOR_KLUDGE is defined,
123 try to do the same for all objects indirectly
124 referenced by typeglobs too. Called once from
125 perl_destruct(), prior to calling sv_clean_all()
126 below.
127
128 sv_clean_all() / do_clean_all()
129 SvREFCNT_dec(sv) each remaining SV, possibly
130 triggering an sv_free(). It also sets the
131 SVf_BREAK flag on the SV to indicate that the
132 refcnt has been artificially lowered, and thus
133 stopping sv_free() from giving spurious warnings
134 about SVs which unexpectedly have a refcnt
135 of zero. called repeatedly from perl_destruct()
136 until there are no SVs left.
137
93e68bfb 138=head2 Arena allocator API Summary
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139
140Private API to rest of sv.c
141
142 new_SV(), del_SV(),
143
144 new_XIV(), del_XIV(),
145 new_XNV(), del_XNV(),
146 etc
147
148Public API:
149
8cf8f3d1 150 sv_report_used(), sv_clean_objs(), sv_clean_all(), sv_free_arenas()
645c22ef 151
645c22ef
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152=cut
153
154============================================================================ */
155
4561caa4
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156/*
157 * "A time to plant, and a time to uproot what was planted..."
158 */
159
77354fb4
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160/*
161 * nice_chunk and nice_chunk size need to be set
162 * and queried under the protection of sv_mutex
163 */
164void
165Perl_offer_nice_chunk(pTHX_ void *chunk, U32 chunk_size)
166{
97aff369 167 dVAR;
77354fb4
NC
168 void *new_chunk;
169 U32 new_chunk_size;
170 LOCK_SV_MUTEX;
171 new_chunk = (void *)(chunk);
172 new_chunk_size = (chunk_size);
173 if (new_chunk_size > PL_nice_chunk_size) {
174 Safefree(PL_nice_chunk);
175 PL_nice_chunk = (char *) new_chunk;
176 PL_nice_chunk_size = new_chunk_size;
177 } else {
178 Safefree(chunk);
179 }
180 UNLOCK_SV_MUTEX;
181}
cac9b346 182
fd0854ff 183#ifdef DEBUG_LEAKING_SCALARS
22162ca8 184# define FREE_SV_DEBUG_FILE(sv) Safefree((sv)->sv_debug_file)
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185#else
186# define FREE_SV_DEBUG_FILE(sv)
187#endif
188
48614a46
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189#ifdef PERL_POISON
190# define SvARENA_CHAIN(sv) ((sv)->sv_u.svu_rv)
191/* Whilst I'd love to do this, it seems that things like to check on
192 unreferenced scalars
7e337ee0 193# define POSION_SV_HEAD(sv) PoisonNew(sv, 1, struct STRUCT_SV)
48614a46 194*/
7e337ee0
JH
195# define POSION_SV_HEAD(sv) PoisonNew(&SvANY(sv), 1, void *), \
196 PoisonNew(&SvREFCNT(sv), 1, U32)
48614a46
NC
197#else
198# define SvARENA_CHAIN(sv) SvANY(sv)
199# define POSION_SV_HEAD(sv)
200#endif
201
053fc874
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202#define plant_SV(p) \
203 STMT_START { \
fd0854ff 204 FREE_SV_DEBUG_FILE(p); \
48614a46
NC
205 POSION_SV_HEAD(p); \
206 SvARENA_CHAIN(p) = (void *)PL_sv_root; \
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207 SvFLAGS(p) = SVTYPEMASK; \
208 PL_sv_root = (p); \
209 --PL_sv_count; \
210 } STMT_END
a0d0e21e 211
fba3b22e 212/* sv_mutex must be held while calling uproot_SV() */
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213#define uproot_SV(p) \
214 STMT_START { \
215 (p) = PL_sv_root; \
bb7bbd9c 216 PL_sv_root = (SV*)SvARENA_CHAIN(p); \
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217 ++PL_sv_count; \
218 } STMT_END
219
645c22ef 220
cac9b346
NC
221/* make some more SVs by adding another arena */
222
223/* sv_mutex must be held while calling more_sv() */
224STATIC SV*
225S_more_sv(pTHX)
226{
97aff369 227 dVAR;
cac9b346
NC
228 SV* sv;
229
230 if (PL_nice_chunk) {
231 sv_add_arena(PL_nice_chunk, PL_nice_chunk_size, 0);
bd61b366 232 PL_nice_chunk = NULL;
cac9b346
NC
233 PL_nice_chunk_size = 0;
234 }
235 else {
236 char *chunk; /* must use New here to match call to */
d2a0f284 237 Newx(chunk,PERL_ARENA_SIZE,char); /* Safefree() in sv_free_arenas() */
2e7ed132 238 sv_add_arena(chunk, PERL_ARENA_SIZE, 0);
cac9b346
NC
239 }
240 uproot_SV(sv);
241 return sv;
242}
243
645c22ef
DM
244/* new_SV(): return a new, empty SV head */
245
eba0f806
DM
246#ifdef DEBUG_LEAKING_SCALARS
247/* provide a real function for a debugger to play with */
248STATIC SV*
249S_new_SV(pTHX)
250{
251 SV* sv;
252
253 LOCK_SV_MUTEX;
254 if (PL_sv_root)
255 uproot_SV(sv);
256 else
cac9b346 257 sv = S_more_sv(aTHX);
eba0f806
DM
258 UNLOCK_SV_MUTEX;
259 SvANY(sv) = 0;
260 SvREFCNT(sv) = 1;
261 SvFLAGS(sv) = 0;
fd0854ff
DM
262 sv->sv_debug_optype = PL_op ? PL_op->op_type : 0;
263 sv->sv_debug_line = (U16) ((PL_copline == NOLINE) ?
264 (PL_curcop ? CopLINE(PL_curcop) : 0) : PL_copline);
265 sv->sv_debug_inpad = 0;
266 sv->sv_debug_cloned = 0;
fd0854ff 267 sv->sv_debug_file = PL_curcop ? savepv(CopFILE(PL_curcop)): NULL;
fd0854ff 268
eba0f806
DM
269 return sv;
270}
271# define new_SV(p) (p)=S_new_SV(aTHX)
272
273#else
274# define new_SV(p) \
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GS
275 STMT_START { \
276 LOCK_SV_MUTEX; \
277 if (PL_sv_root) \
278 uproot_SV(p); \
279 else \
cac9b346 280 (p) = S_more_sv(aTHX); \
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GS
281 UNLOCK_SV_MUTEX; \
282 SvANY(p) = 0; \
283 SvREFCNT(p) = 1; \
284 SvFLAGS(p) = 0; \
285 } STMT_END
eba0f806 286#endif
463ee0b2 287
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DM
288
289/* del_SV(): return an empty SV head to the free list */
290
a0d0e21e 291#ifdef DEBUGGING
4561caa4 292
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293#define del_SV(p) \
294 STMT_START { \
295 LOCK_SV_MUTEX; \
aea4f609 296 if (DEBUG_D_TEST) \
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GS
297 del_sv(p); \
298 else \
299 plant_SV(p); \
300 UNLOCK_SV_MUTEX; \
301 } STMT_END
a0d0e21e 302
76e3520e 303STATIC void
cea2e8a9 304S_del_sv(pTHX_ SV *p)
463ee0b2 305{
97aff369 306 dVAR;
aea4f609 307 if (DEBUG_D_TEST) {
4633a7c4 308 SV* sva;
a3b680e6 309 bool ok = 0;
3280af22 310 for (sva = PL_sv_arenaroot; sva; sva = (SV *) SvANY(sva)) {
53c1dcc0
AL
311 const SV * const sv = sva + 1;
312 const SV * const svend = &sva[SvREFCNT(sva)];
c0ff570e 313 if (p >= sv && p < svend) {
a0d0e21e 314 ok = 1;
c0ff570e
NC
315 break;
316 }
a0d0e21e
LW
317 }
318 if (!ok) {
0453d815 319 if (ckWARN_d(WARN_INTERNAL))
9014280d 320 Perl_warner(aTHX_ packWARN(WARN_INTERNAL),
472d47bc
SB
321 "Attempt to free non-arena SV: 0x%"UVxf
322 pTHX__FORMAT, PTR2UV(p) pTHX__VALUE);
a0d0e21e
LW
323 return;
324 }
325 }
4561caa4 326 plant_SV(p);
463ee0b2 327}
a0d0e21e 328
4561caa4
CS
329#else /* ! DEBUGGING */
330
331#define del_SV(p) plant_SV(p)
332
333#endif /* DEBUGGING */
463ee0b2 334
645c22ef
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335
336/*
ccfc67b7
JH
337=head1 SV Manipulation Functions
338
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DM
339=for apidoc sv_add_arena
340
341Given a chunk of memory, link it to the head of the list of arenas,
342and split it into a list of free SVs.
343
344=cut
345*/
346
4633a7c4 347void
864dbfa3 348Perl_sv_add_arena(pTHX_ char *ptr, U32 size, U32 flags)
463ee0b2 349{
97aff369 350 dVAR;
0bd48802 351 SV* const sva = (SV*)ptr;
463ee0b2
LW
352 register SV* sv;
353 register SV* svend;
4633a7c4
LW
354
355 /* The first SV in an arena isn't an SV. */
3280af22 356 SvANY(sva) = (void *) PL_sv_arenaroot; /* ptr to next arena */
4633a7c4
LW
357 SvREFCNT(sva) = size / sizeof(SV); /* number of SV slots */
358 SvFLAGS(sva) = flags; /* FAKE if not to be freed */
359
3280af22
NIS
360 PL_sv_arenaroot = sva;
361 PL_sv_root = sva + 1;
4633a7c4
LW
362
363 svend = &sva[SvREFCNT(sva) - 1];
364 sv = sva + 1;
463ee0b2 365 while (sv < svend) {
48614a46 366 SvARENA_CHAIN(sv) = (void *)(SV*)(sv + 1);
03e36789 367#ifdef DEBUGGING
978b032e 368 SvREFCNT(sv) = 0;
03e36789
NC
369#endif
370 /* Must always set typemask because it's awlays checked in on cleanup
371 when the arenas are walked looking for objects. */
8990e307 372 SvFLAGS(sv) = SVTYPEMASK;
463ee0b2
LW
373 sv++;
374 }
48614a46 375 SvARENA_CHAIN(sv) = 0;
03e36789
NC
376#ifdef DEBUGGING
377 SvREFCNT(sv) = 0;
378#endif
4633a7c4
LW
379 SvFLAGS(sv) = SVTYPEMASK;
380}
381
055972dc
DM
382/* visit(): call the named function for each non-free SV in the arenas
383 * whose flags field matches the flags/mask args. */
645c22ef 384
5226ed68 385STATIC I32
055972dc 386S_visit(pTHX_ SVFUNC_t f, U32 flags, U32 mask)
8990e307 387{
97aff369 388 dVAR;
4633a7c4 389 SV* sva;
5226ed68 390 I32 visited = 0;
8990e307 391
3280af22 392 for (sva = PL_sv_arenaroot; sva; sva = (SV*)SvANY(sva)) {
53c1dcc0 393 register const SV * const svend = &sva[SvREFCNT(sva)];
a3b680e6 394 register SV* sv;
4561caa4 395 for (sv = sva + 1; sv < svend; ++sv) {
055972dc
DM
396 if (SvTYPE(sv) != SVTYPEMASK
397 && (sv->sv_flags & mask) == flags
398 && SvREFCNT(sv))
399 {
acfe0abc 400 (FCALL)(aTHX_ sv);
5226ed68
JH
401 ++visited;
402 }
8990e307
LW
403 }
404 }
5226ed68 405 return visited;
8990e307
LW
406}
407
758a08c3
JH
408#ifdef DEBUGGING
409
645c22ef
DM
410/* called by sv_report_used() for each live SV */
411
412static void
acfe0abc 413do_report_used(pTHX_ SV *sv)
645c22ef
DM
414{
415 if (SvTYPE(sv) != SVTYPEMASK) {
416 PerlIO_printf(Perl_debug_log, "****\n");
417 sv_dump(sv);
418 }
419}
758a08c3 420#endif
645c22ef
DM
421
422/*
423=for apidoc sv_report_used
424
425Dump the contents of all SVs not yet freed. (Debugging aid).
426
427=cut
428*/
429
8990e307 430void
864dbfa3 431Perl_sv_report_used(pTHX)
4561caa4 432{
ff270d3a 433#ifdef DEBUGGING
055972dc 434 visit(do_report_used, 0, 0);
96a5add6
AL
435#else
436 PERL_UNUSED_CONTEXT;
ff270d3a 437#endif
4561caa4
CS
438}
439
645c22ef
DM
440/* called by sv_clean_objs() for each live SV */
441
442static void
e15faf7d 443do_clean_objs(pTHX_ SV *ref)
645c22ef 444{
97aff369 445 dVAR;
823a54a3
AL
446 if (SvROK(ref)) {
447 SV * const target = SvRV(ref);
448 if (SvOBJECT(target)) {
449 DEBUG_D((PerlIO_printf(Perl_debug_log, "Cleaning object ref:\n "), sv_dump(ref)));
450 if (SvWEAKREF(ref)) {
451 sv_del_backref(target, ref);
452 SvWEAKREF_off(ref);
453 SvRV_set(ref, NULL);
454 } else {
455 SvROK_off(ref);
456 SvRV_set(ref, NULL);
457 SvREFCNT_dec(target);
458 }
645c22ef
DM
459 }
460 }
461
462 /* XXX Might want to check arrays, etc. */
463}
464
465/* called by sv_clean_objs() for each live SV */
466
467#ifndef DISABLE_DESTRUCTOR_KLUDGE
468static void
acfe0abc 469do_clean_named_objs(pTHX_ SV *sv)
645c22ef 470{
97aff369 471 dVAR;
f7877b28 472 if (SvTYPE(sv) == SVt_PVGV && isGV_with_GP(sv) && GvGP(sv)) {
c69033f2
NC
473 if ((
474#ifdef PERL_DONT_CREATE_GVSV
475 GvSV(sv) &&
476#endif
477 SvOBJECT(GvSV(sv))) ||
645c22ef
DM
478 (GvAV(sv) && SvOBJECT(GvAV(sv))) ||
479 (GvHV(sv) && SvOBJECT(GvHV(sv))) ||
480 (GvIO(sv) && SvOBJECT(GvIO(sv))) ||
481 (GvCV(sv) && SvOBJECT(GvCV(sv))) )
482 {
483 DEBUG_D((PerlIO_printf(Perl_debug_log, "Cleaning named glob object:\n "), sv_dump(sv)));
ec5f3c78 484 SvFLAGS(sv) |= SVf_BREAK;
645c22ef
DM
485 SvREFCNT_dec(sv);
486 }
487 }
488}
489#endif
490
491/*
492=for apidoc sv_clean_objs
493
494Attempt to destroy all objects not yet freed
495
496=cut
497*/
498
4561caa4 499void
864dbfa3 500Perl_sv_clean_objs(pTHX)
4561caa4 501{
97aff369 502 dVAR;
3280af22 503 PL_in_clean_objs = TRUE;
055972dc 504 visit(do_clean_objs, SVf_ROK, SVf_ROK);
4561caa4 505#ifndef DISABLE_DESTRUCTOR_KLUDGE
2d0f3c12 506 /* some barnacles may yet remain, clinging to typeglobs */
055972dc 507 visit(do_clean_named_objs, SVt_PVGV, SVTYPEMASK);
4561caa4 508#endif
3280af22 509 PL_in_clean_objs = FALSE;
4561caa4
CS
510}
511
645c22ef
DM
512/* called by sv_clean_all() for each live SV */
513
514static void
acfe0abc 515do_clean_all(pTHX_ SV *sv)
645c22ef 516{
97aff369 517 dVAR;
645c22ef
DM
518 DEBUG_D((PerlIO_printf(Perl_debug_log, "Cleaning loops: SV at 0x%"UVxf"\n", PTR2UV(sv)) ));
519 SvFLAGS(sv) |= SVf_BREAK;
0e705b3b 520 if (PL_comppad == (AV*)sv) {
7d49f689 521 PL_comppad = NULL;
4608196e 522 PL_curpad = NULL;
0e705b3b 523 }
645c22ef
DM
524 SvREFCNT_dec(sv);
525}
526
527/*
528=for apidoc sv_clean_all
529
530Decrement the refcnt of each remaining SV, possibly triggering a
531cleanup. This function may have to be called multiple times to free
ff276b08 532SVs which are in complex self-referential hierarchies.
645c22ef
DM
533
534=cut
535*/
536
5226ed68 537I32
864dbfa3 538Perl_sv_clean_all(pTHX)
8990e307 539{
97aff369 540 dVAR;
5226ed68 541 I32 cleaned;
3280af22 542 PL_in_clean_all = TRUE;
055972dc 543 cleaned = visit(do_clean_all, 0,0);
3280af22 544 PL_in_clean_all = FALSE;
5226ed68 545 return cleaned;
8990e307 546}
463ee0b2 547
5e258f8c
JC
548/*
549 ARENASETS: a meta-arena implementation which separates arena-info
550 into struct arena_set, which contains an array of struct
551 arena_descs, each holding info for a single arena. By separating
552 the meta-info from the arena, we recover the 1st slot, formerly
553 borrowed for list management. The arena_set is about the size of an
554 arena, avoiding the needless malloc overhead of a naive linked-list
555
556 The cost is 1 arena-set malloc per ~320 arena-mallocs, + the unused
557 memory in the last arena-set (1/2 on average). In trade, we get
558 back the 1st slot in each arena (ie 1.7% of a CV-arena, less for
d2a0f284
JC
559 smaller types). The recovery of the wasted space allows use of
560 small arenas for large, rare body types,
5e258f8c 561*/
5e258f8c 562struct arena_desc {
398c677b
NC
563 char *arena; /* the raw storage, allocated aligned */
564 size_t size; /* its size ~4k typ */
565 int unit_type; /* useful for arena audits */
5e258f8c
JC
566 /* info for sv-heads (eventually)
567 int count, flags;
568 */
569};
570
e6148039
NC
571struct arena_set;
572
573/* Get the maximum number of elements in set[] such that struct arena_set
574 will fit within PERL_ARENA_SIZE, which is probabably just under 4K, and
575 therefore likely to be 1 aligned memory page. */
576
577#define ARENAS_PER_SET ((PERL_ARENA_SIZE - sizeof(struct arena_set*) \
578 - 2 * sizeof(int)) / sizeof (struct arena_desc))
5e258f8c
JC
579
580struct arena_set {
581 struct arena_set* next;
582 int set_size; /* ie ARENAS_PER_SET */
583 int curr; /* index of next available arena-desc */
584 struct arena_desc set[ARENAS_PER_SET];
585};
586
645c22ef
DM
587/*
588=for apidoc sv_free_arenas
589
590Deallocate the memory used by all arenas. Note that all the individual SV
591heads and bodies within the arenas must already have been freed.
592
593=cut
594*/
4633a7c4 595void
864dbfa3 596Perl_sv_free_arenas(pTHX)
4633a7c4 597{
97aff369 598 dVAR;
4633a7c4
LW
599 SV* sva;
600 SV* svanext;
93e68bfb 601 int i;
4633a7c4
LW
602
603 /* Free arenas here, but be careful about fake ones. (We assume
604 contiguity of the fake ones with the corresponding real ones.) */
605
3280af22 606 for (sva = PL_sv_arenaroot; sva; sva = svanext) {
4633a7c4
LW
607 svanext = (SV*) SvANY(sva);
608 while (svanext && SvFAKE(svanext))
609 svanext = (SV*) SvANY(svanext);
610
611 if (!SvFAKE(sva))
1df70142 612 Safefree(sva);
4633a7c4 613 }
93e68bfb 614
5e258f8c
JC
615 {
616 struct arena_set *next, *aroot = (struct arena_set*) PL_body_arenas;
617
618 for (; aroot; aroot = next) {
96a5add6 619 const int max = aroot->curr;
5e258f8c
JC
620 for (i=0; i<max; i++) {
621 assert(aroot->set[i].arena);
622 Safefree(aroot->set[i].arena);
623 }
624 next = aroot->next;
625 Safefree(aroot);
626 }
627 }
dc8220bf 628 PL_body_arenas = 0;
fdda85ca 629
232d1c15 630 for (i=0; i<PERL_ARENA_ROOTS_SIZE; i++)
93e68bfb 631 PL_body_roots[i] = 0;
93e68bfb 632
43c5f42d 633 Safefree(PL_nice_chunk);
bd61b366 634 PL_nice_chunk = NULL;
3280af22
NIS
635 PL_nice_chunk_size = 0;
636 PL_sv_arenaroot = 0;
637 PL_sv_root = 0;
4633a7c4
LW
638}
639
bd81e77b
NC
640/*
641 Here are mid-level routines that manage the allocation of bodies out
642 of the various arenas. There are 5 kinds of arenas:
29489e7c 643
bd81e77b
NC
644 1. SV-head arenas, which are discussed and handled above
645 2. regular body arenas
646 3. arenas for reduced-size bodies
647 4. Hash-Entry arenas
648 5. pte arenas (thread related)
29489e7c 649
bd81e77b
NC
650 Arena types 2 & 3 are chained by body-type off an array of
651 arena-root pointers, which is indexed by svtype. Some of the
652 larger/less used body types are malloced singly, since a large
653 unused block of them is wasteful. Also, several svtypes dont have
654 bodies; the data fits into the sv-head itself. The arena-root
655 pointer thus has a few unused root-pointers (which may be hijacked
656 later for arena types 4,5)
29489e7c 657
bd81e77b
NC
658 3 differs from 2 as an optimization; some body types have several
659 unused fields in the front of the structure (which are kept in-place
660 for consistency). These bodies can be allocated in smaller chunks,
661 because the leading fields arent accessed. Pointers to such bodies
662 are decremented to point at the unused 'ghost' memory, knowing that
663 the pointers are used with offsets to the real memory.
29489e7c 664
bd81e77b
NC
665 HE, HEK arenas are managed separately, with separate code, but may
666 be merge-able later..
667
668 PTE arenas are not sv-bodies, but they share these mid-level
669 mechanics, so are considered here. The new mid-level mechanics rely
670 on the sv_type of the body being allocated, so we just reserve one
671 of the unused body-slots for PTEs, then use it in those (2) PTE
672 contexts below (line ~10k)
673*/
674
bd26d9a3 675/* get_arena(size): this creates custom-sized arenas
5e258f8c
JC
676 TBD: export properly for hv.c: S_more_he().
677*/
678void*
679Perl_get_arena(pTHX_ int arena_size)
680{
7a89be66 681 dVAR;
5e258f8c 682 struct arena_desc* adesc;
476a1e16 683 struct arena_set *newroot, **aroot = (struct arena_set**) &PL_body_arenas;
5e258f8c
JC
684 int curr;
685
476a1e16
JC
686 /* shouldnt need this
687 if (!arena_size) arena_size = PERL_ARENA_SIZE;
688 */
5e258f8c
JC
689
690 /* may need new arena-set to hold new arena */
476a1e16 691 if (!*aroot || (*aroot)->curr >= (*aroot)->set_size) {
5e258f8c
JC
692 Newxz(newroot, 1, struct arena_set);
693 newroot->set_size = ARENAS_PER_SET;
476a1e16
JC
694 newroot->next = *aroot;
695 *aroot = newroot;
ca0270c4 696 DEBUG_m(PerlIO_printf(Perl_debug_log, "new arenaset %p\n", (void*)*aroot));
5e258f8c
JC
697 }
698
699 /* ok, now have arena-set with at least 1 empty/available arena-desc */
476a1e16
JC
700 curr = (*aroot)->curr++;
701 adesc = &((*aroot)->set[curr]);
5e258f8c
JC
702 assert(!adesc->arena);
703
5e258f8c
JC
704 Newxz(adesc->arena, arena_size, char);
705 adesc->size = arena_size;
d2a0f284 706 DEBUG_m(PerlIO_printf(Perl_debug_log, "arena %d added: %p size %d\n",
6c9570dc 707 curr, (void*)adesc->arena, arena_size));
5e258f8c
JC
708
709 return adesc->arena;
5e258f8c
JC
710}
711
53c1dcc0 712
bd81e77b 713/* return a thing to the free list */
29489e7c 714
bd81e77b
NC
715#define del_body(thing, root) \
716 STMT_START { \
00b6aa41 717 void ** const thing_copy = (void **)thing;\
bd81e77b
NC
718 LOCK_SV_MUTEX; \
719 *thing_copy = *root; \
720 *root = (void*)thing_copy; \
721 UNLOCK_SV_MUTEX; \
722 } STMT_END
29489e7c 723
bd81e77b 724/*
d2a0f284
JC
725
726=head1 SV-Body Allocation
727
728Allocation of SV-bodies is similar to SV-heads, differing as follows;
729the allocation mechanism is used for many body types, so is somewhat
730more complicated, it uses arena-sets, and has no need for still-live
731SV detection.
732
733At the outermost level, (new|del)_X*V macros return bodies of the
734appropriate type. These macros call either (new|del)_body_type or
735(new|del)_body_allocated macro pairs, depending on specifics of the
736type. Most body types use the former pair, the latter pair is used to
737allocate body types with "ghost fields".
738
739"ghost fields" are fields that are unused in certain types, and
740consequently dont need to actually exist. They are declared because
741they're part of a "base type", which allows use of functions as
742methods. The simplest examples are AVs and HVs, 2 aggregate types
743which don't use the fields which support SCALAR semantics.
744
745For these types, the arenas are carved up into *_allocated size
746chunks, we thus avoid wasted memory for those unaccessed members.
747When bodies are allocated, we adjust the pointer back in memory by the
748size of the bit not allocated, so it's as if we allocated the full
749structure. (But things will all go boom if you write to the part that
750is "not there", because you'll be overwriting the last members of the
751preceding structure in memory.)
752
753We calculate the correction using the STRUCT_OFFSET macro. For
754example, if xpv_allocated is the same structure as XPV then the two
755OFFSETs sum to zero, and the pointer is unchanged. If the allocated
756structure is smaller (no initial NV actually allocated) then the net
757effect is to subtract the size of the NV from the pointer, to return a
758new pointer as if an initial NV were actually allocated.
759
760This is the same trick as was used for NV and IV bodies. Ironically it
761doesn't need to be used for NV bodies any more, because NV is now at
762the start of the structure. IV bodies don't need it either, because
763they are no longer allocated.
764
765In turn, the new_body_* allocators call S_new_body(), which invokes
766new_body_inline macro, which takes a lock, and takes a body off the
767linked list at PL_body_roots[sv_type], calling S_more_bodies() if
768necessary to refresh an empty list. Then the lock is released, and
769the body is returned.
770
771S_more_bodies calls get_arena(), and carves it up into an array of N
772bodies, which it strings into a linked list. It looks up arena-size
773and body-size from the body_details table described below, thus
774supporting the multiple body-types.
775
776If PURIFY is defined, or PERL_ARENA_SIZE=0, arenas are not used, and
777the (new|del)_X*V macros are mapped directly to malloc/free.
778
779*/
780
781/*
782
783For each sv-type, struct body_details bodies_by_type[] carries
784parameters which control these aspects of SV handling:
785
786Arena_size determines whether arenas are used for this body type, and if
787so, how big they are. PURIFY or PERL_ARENA_SIZE=0 set this field to
788zero, forcing individual mallocs and frees.
789
790Body_size determines how big a body is, and therefore how many fit into
791each arena. Offset carries the body-pointer adjustment needed for
792*_allocated body types, and is used in *_allocated macros.
793
794But its main purpose is to parameterize info needed in
795Perl_sv_upgrade(). The info here dramatically simplifies the function
796vs the implementation in 5.8.7, making it table-driven. All fields
797are used for this, except for arena_size.
798
799For the sv-types that have no bodies, arenas are not used, so those
800PL_body_roots[sv_type] are unused, and can be overloaded. In
801something of a special case, SVt_NULL is borrowed for HE arenas;
802PL_body_roots[SVt_NULL] is filled by S_more_he, but the
803bodies_by_type[SVt_NULL] slot is not used, as the table is not
804available in hv.c,
805
806PTEs also use arenas, but are never seen in Perl_sv_upgrade.
807Nonetheless, they get their own slot in bodies_by_type[SVt_NULL], so
808they can just use the same allocation semantics. At first, PTEs were
809also overloaded to a non-body sv-type, but this yielded hard-to-find
810malloc bugs, so was simplified by claiming a new slot. This choice
811has no consequence at this time.
812
29489e7c
DM
813*/
814
bd81e77b 815struct body_details {
0fb58b32 816 U8 body_size; /* Size to allocate */
10666ae3 817 U8 copy; /* Size of structure to copy (may be shorter) */
0fb58b32 818 U8 offset;
10666ae3
NC
819 unsigned int type : 4; /* We have space for a sanity check. */
820 unsigned int cant_upgrade : 1; /* Cannot upgrade this type */
821 unsigned int zero_nv : 1; /* zero the NV when upgrading from this */
822 unsigned int arena : 1; /* Allocated from an arena */
823 size_t arena_size; /* Size of arena to allocate */
bd81e77b 824};
29489e7c 825
bd81e77b
NC
826#define HADNV FALSE
827#define NONV TRUE
29489e7c 828
d2a0f284 829
bd81e77b
NC
830#ifdef PURIFY
831/* With -DPURFIY we allocate everything directly, and don't use arenas.
832 This seems a rather elegant way to simplify some of the code below. */
833#define HASARENA FALSE
834#else
835#define HASARENA TRUE
836#endif
837#define NOARENA FALSE
29489e7c 838
d2a0f284
JC
839/* Size the arenas to exactly fit a given number of bodies. A count
840 of 0 fits the max number bodies into a PERL_ARENA_SIZE.block,
841 simplifying the default. If count > 0, the arena is sized to fit
842 only that many bodies, allowing arenas to be used for large, rare
843 bodies (XPVFM, XPVIO) without undue waste. The arena size is
844 limited by PERL_ARENA_SIZE, so we can safely oversize the
845 declarations.
846 */
95db5f15
MB
847#define FIT_ARENA0(body_size) \
848 ((size_t)(PERL_ARENA_SIZE / body_size) * body_size)
849#define FIT_ARENAn(count,body_size) \
850 ( count * body_size <= PERL_ARENA_SIZE) \
851 ? count * body_size \
852 : FIT_ARENA0 (body_size)
853#define FIT_ARENA(count,body_size) \
854 count \
855 ? FIT_ARENAn (count, body_size) \
856 : FIT_ARENA0 (body_size)
d2a0f284 857
bd81e77b 858/* A macro to work out the offset needed to subtract from a pointer to (say)
29489e7c 859
bd81e77b
NC
860typedef struct {
861 STRLEN xpv_cur;
862 STRLEN xpv_len;
863} xpv_allocated;
29489e7c 864
bd81e77b 865to make its members accessible via a pointer to (say)
29489e7c 866
bd81e77b
NC
867struct xpv {
868 NV xnv_nv;
869 STRLEN xpv_cur;
870 STRLEN xpv_len;
871};
29489e7c 872
bd81e77b 873*/
29489e7c 874
bd81e77b
NC
875#define relative_STRUCT_OFFSET(longer, shorter, member) \
876 (STRUCT_OFFSET(shorter, member) - STRUCT_OFFSET(longer, member))
29489e7c 877
bd81e77b
NC
878/* Calculate the length to copy. Specifically work out the length less any
879 final padding the compiler needed to add. See the comment in sv_upgrade
880 for why copying the padding proved to be a bug. */
29489e7c 881
bd81e77b
NC
882#define copy_length(type, last_member) \
883 STRUCT_OFFSET(type, last_member) \
884 + sizeof (((type*)SvANY((SV*)0))->last_member)
29489e7c 885
bd81e77b 886static const struct body_details bodies_by_type[] = {
10666ae3
NC
887 { sizeof(HE), 0, 0, SVt_NULL,
888 FALSE, NONV, NOARENA, FIT_ARENA(0, sizeof(HE)) },
d2a0f284 889
1cb9cd50
NC
890 /* The bind placeholder pretends to be an RV for now.
891 Also it's marked as "can't upgrade" top stop anyone using it before it's
892 implemented. */
893 { 0, 0, 0, SVt_BIND, TRUE, NONV, NOARENA, 0 },
894
d2a0f284
JC
895 /* IVs are in the head, so the allocation size is 0.
896 However, the slot is overloaded for PTEs. */
897 { sizeof(struct ptr_tbl_ent), /* This is used for PTEs. */
898 sizeof(IV), /* This is used to copy out the IV body. */
10666ae3 899 STRUCT_OFFSET(XPVIV, xiv_iv), SVt_IV, FALSE, NONV,
d2a0f284
JC
900 NOARENA /* IVS don't need an arena */,
901 /* But PTEs need to know the size of their arena */
902 FIT_ARENA(0, sizeof(struct ptr_tbl_ent))
903 },
904
bd81e77b 905 /* 8 bytes on most ILP32 with IEEE doubles */
10666ae3 906 { sizeof(NV), sizeof(NV), 0, SVt_NV, FALSE, HADNV, HASARENA,
d2a0f284
JC
907 FIT_ARENA(0, sizeof(NV)) },
908
909 /* RVs are in the head now. */
10666ae3 910 { 0, 0, 0, SVt_RV, FALSE, NONV, NOARENA, 0 },
d2a0f284 911
bd81e77b 912 /* 8 bytes on most ILP32 with IEEE doubles */
d2a0f284
JC
913 { sizeof(xpv_allocated),
914 copy_length(XPV, xpv_len)
915 - relative_STRUCT_OFFSET(xpv_allocated, XPV, xpv_cur),
916 + relative_STRUCT_OFFSET(xpv_allocated, XPV, xpv_cur),
10666ae3 917 SVt_PV, FALSE, NONV, HASARENA, FIT_ARENA(0, sizeof(xpv_allocated)) },
d2a0f284 918
bd81e77b 919 /* 12 */
d2a0f284
JC
920 { sizeof(xpviv_allocated),
921 copy_length(XPVIV, xiv_u)
922 - relative_STRUCT_OFFSET(xpviv_allocated, XPVIV, xpv_cur),
923 + relative_STRUCT_OFFSET(xpviv_allocated, XPVIV, xpv_cur),
10666ae3 924 SVt_PVIV, FALSE, NONV, HASARENA, FIT_ARENA(0, sizeof(xpviv_allocated)) },
d2a0f284 925
bd81e77b 926 /* 20 */
10666ae3 927 { sizeof(XPVNV), copy_length(XPVNV, xiv_u), 0, SVt_PVNV, FALSE, HADNV,
d2a0f284
JC
928 HASARENA, FIT_ARENA(0, sizeof(XPVNV)) },
929
bd81e77b 930 /* 28 */
10666ae3 931 { sizeof(XPVMG), copy_length(XPVMG, xmg_stash), 0, SVt_PVMG, FALSE, HADNV,
d2a0f284
JC
932 HASARENA, FIT_ARENA(0, sizeof(XPVMG)) },
933
bd81e77b 934 /* 48 */
10666ae3 935 { sizeof(XPVGV), sizeof(XPVGV), 0, SVt_PVGV, TRUE, HADNV,
d2a0f284
JC
936 HASARENA, FIT_ARENA(0, sizeof(XPVGV)) },
937
bd81e77b 938 /* 64 */
10666ae3 939 { sizeof(XPVLV), sizeof(XPVLV), 0, SVt_PVLV, TRUE, HADNV,
d2a0f284
JC
940 HASARENA, FIT_ARENA(0, sizeof(XPVLV)) },
941
942 { sizeof(xpvav_allocated),
943 copy_length(XPVAV, xmg_stash)
944 - relative_STRUCT_OFFSET(xpvav_allocated, XPVAV, xav_fill),
945 + relative_STRUCT_OFFSET(xpvav_allocated, XPVAV, xav_fill),
10666ae3 946 SVt_PVAV, TRUE, HADNV, HASARENA, FIT_ARENA(0, sizeof(xpvav_allocated)) },
d2a0f284
JC
947
948 { sizeof(xpvhv_allocated),
949 copy_length(XPVHV, xmg_stash)
950 - relative_STRUCT_OFFSET(xpvhv_allocated, XPVHV, xhv_fill),
951 + relative_STRUCT_OFFSET(xpvhv_allocated, XPVHV, xhv_fill),
10666ae3 952 SVt_PVHV, TRUE, HADNV, HASARENA, FIT_ARENA(0, sizeof(xpvhv_allocated)) },
d2a0f284 953
c84c4652 954 /* 56 */
4115f141 955 { sizeof(xpvcv_allocated), sizeof(xpvcv_allocated),
c84c4652 956 + relative_STRUCT_OFFSET(xpvcv_allocated, XPVCV, xpv_cur),
10666ae3 957 SVt_PVCV, TRUE, NONV, HASARENA, FIT_ARENA(0, sizeof(xpvcv_allocated)) },
d2a0f284 958
4115f141 959 { sizeof(xpvfm_allocated), sizeof(xpvfm_allocated),
3038937b 960 + relative_STRUCT_OFFSET(xpvfm_allocated, XPVFM, xpv_cur),
10666ae3 961 SVt_PVFM, TRUE, NONV, NOARENA, FIT_ARENA(20, sizeof(xpvfm_allocated)) },
d2a0f284
JC
962
963 /* XPVIO is 84 bytes, fits 48x */
10666ae3 964 { sizeof(XPVIO), sizeof(XPVIO), 0, SVt_PVIO, TRUE, HADNV,
d2a0f284 965 HASARENA, FIT_ARENA(24, sizeof(XPVIO)) },
bd81e77b 966};
29489e7c 967
d2a0f284
JC
968#define new_body_type(sv_type) \
969 (void *)((char *)S_new_body(aTHX_ sv_type))
29489e7c 970
bd81e77b
NC
971#define del_body_type(p, sv_type) \
972 del_body(p, &PL_body_roots[sv_type])
29489e7c 973
29489e7c 974
bd81e77b 975#define new_body_allocated(sv_type) \
d2a0f284 976 (void *)((char *)S_new_body(aTHX_ sv_type) \
bd81e77b 977 - bodies_by_type[sv_type].offset)
29489e7c 978
bd81e77b
NC
979#define del_body_allocated(p, sv_type) \
980 del_body(p + bodies_by_type[sv_type].offset, &PL_body_roots[sv_type])
29489e7c 981
29489e7c 982
bd81e77b
NC
983#define my_safemalloc(s) (void*)safemalloc(s)
984#define my_safecalloc(s) (void*)safecalloc(s, 1)
985#define my_safefree(p) safefree((char*)p)
29489e7c 986
bd81e77b 987#ifdef PURIFY
29489e7c 988
bd81e77b
NC
989#define new_XNV() my_safemalloc(sizeof(XPVNV))
990#define del_XNV(p) my_safefree(p)
29489e7c 991
bd81e77b
NC
992#define new_XPVNV() my_safemalloc(sizeof(XPVNV))
993#define del_XPVNV(p) my_safefree(p)
29489e7c 994
bd81e77b
NC
995#define new_XPVAV() my_safemalloc(sizeof(XPVAV))
996#define del_XPVAV(p) my_safefree(p)
29489e7c 997
bd81e77b
NC
998#define new_XPVHV() my_safemalloc(sizeof(XPVHV))
999#define del_XPVHV(p) my_safefree(p)
29489e7c 1000
bd81e77b
NC
1001#define new_XPVMG() my_safemalloc(sizeof(XPVMG))
1002#define del_XPVMG(p) my_safefree(p)
29489e7c 1003
bd81e77b
NC
1004#define new_XPVGV() my_safemalloc(sizeof(XPVGV))
1005#define del_XPVGV(p) my_safefree(p)
29489e7c 1006
bd81e77b 1007#else /* !PURIFY */
29489e7c 1008
bd81e77b
NC
1009#define new_XNV() new_body_type(SVt_NV)
1010#define del_XNV(p) del_body_type(p, SVt_NV)
29489e7c 1011
bd81e77b
NC
1012#define new_XPVNV() new_body_type(SVt_PVNV)
1013#define del_XPVNV(p) del_body_type(p, SVt_PVNV)
29489e7c 1014
bd81e77b
NC
1015#define new_XPVAV() new_body_allocated(SVt_PVAV)
1016#define del_XPVAV(p) del_body_allocated(p, SVt_PVAV)
645c22ef 1017
bd81e77b
NC
1018#define new_XPVHV() new_body_allocated(SVt_PVHV)
1019#define del_XPVHV(p) del_body_allocated(p, SVt_PVHV)
645c22ef 1020
bd81e77b
NC
1021#define new_XPVMG() new_body_type(SVt_PVMG)
1022#define del_XPVMG(p) del_body_type(p, SVt_PVMG)
645c22ef 1023
bd81e77b
NC
1024#define new_XPVGV() new_body_type(SVt_PVGV)
1025#define del_XPVGV(p) del_body_type(p, SVt_PVGV)
1d7c1841 1026
bd81e77b 1027#endif /* PURIFY */
93e68bfb 1028
bd81e77b 1029/* no arena for you! */
93e68bfb 1030
bd81e77b 1031#define new_NOARENA(details) \
d2a0f284 1032 my_safemalloc((details)->body_size + (details)->offset)
bd81e77b 1033#define new_NOARENAZ(details) \
d2a0f284
JC
1034 my_safecalloc((details)->body_size + (details)->offset)
1035
0b2d3faa 1036#if defined(DEBUGGING) && !defined(PERL_GLOBAL_STRUCT_PRIVATE)
10666ae3
NC
1037static bool done_sanity_check;
1038#endif
1039
d2a0f284
JC
1040STATIC void *
1041S_more_bodies (pTHX_ svtype sv_type)
1042{
1043 dVAR;
1044 void ** const root = &PL_body_roots[sv_type];
96a5add6 1045 const struct body_details * const bdp = &bodies_by_type[sv_type];
d2a0f284
JC
1046 const size_t body_size = bdp->body_size;
1047 char *start;
1048 const char *end;
1049
1050 assert(bdp->arena_size);
10666ae3 1051
0b2d3faa
JH
1052#if defined(DEBUGGING) && !defined(PERL_GLOBAL_STRUCT_PRIVATE)
1053 /* PERL_GLOBAL_STRUCT_PRIVATE cannot coexist with global
1054 * variables like done_sanity_check. */
10666ae3 1055 if (!done_sanity_check) {
ea471437 1056 unsigned int i = SVt_LAST;
10666ae3
NC
1057
1058 done_sanity_check = TRUE;
1059
1060 while (i--)
1061 assert (bodies_by_type[i].type == i);
1062 }
1063#endif
1064
d2a0f284
JC
1065 start = (char*) Perl_get_arena(aTHX_ bdp->arena_size);
1066
1067 end = start + bdp->arena_size - body_size;
1068
d2a0f284
JC
1069 /* computed count doesnt reflect the 1st slot reservation */
1070 DEBUG_m(PerlIO_printf(Perl_debug_log,
1071 "arena %p end %p arena-size %d type %d size %d ct %d\n",
6c9570dc 1072 (void*)start, (void*)end,
0e84aef4
JH
1073 (int)bdp->arena_size, sv_type, (int)body_size,
1074 (int)bdp->arena_size / (int)body_size));
d2a0f284
JC
1075
1076 *root = (void *)start;
1077
1078 while (start < end) {
1079 char * const next = start + body_size;
1080 *(void**) start = (void *)next;
1081 start = next;
1082 }
1083 *(void **)start = 0;
1084
1085 return *root;
1086}
1087
1088/* grab a new thing from the free list, allocating more if necessary.
1089 The inline version is used for speed in hot routines, and the
1090 function using it serves the rest (unless PURIFY).
1091*/
1092#define new_body_inline(xpv, sv_type) \
1093 STMT_START { \
1094 void ** const r3wt = &PL_body_roots[sv_type]; \
1095 LOCK_SV_MUTEX; \
11b79775
DD
1096 xpv = (PTR_TBL_ENT_t*) (*((void **)(r3wt)) \
1097 ? *((void **)(r3wt)) : more_bodies(sv_type)); \
d2a0f284
JC
1098 *(r3wt) = *(void**)(xpv); \
1099 UNLOCK_SV_MUTEX; \
1100 } STMT_END
1101
1102#ifndef PURIFY
1103
1104STATIC void *
1105S_new_body(pTHX_ svtype sv_type)
1106{
1107 dVAR;
1108 void *xpv;
1109 new_body_inline(xpv, sv_type);
1110 return xpv;
1111}
1112
1113#endif
93e68bfb 1114
bd81e77b
NC
1115/*
1116=for apidoc sv_upgrade
93e68bfb 1117
bd81e77b
NC
1118Upgrade an SV to a more complex form. Generally adds a new body type to the
1119SV, then copies across as much information as possible from the old body.
1120You generally want to use the C<SvUPGRADE> macro wrapper. See also C<svtype>.
93e68bfb 1121
bd81e77b 1122=cut
93e68bfb 1123*/
93e68bfb 1124
bd81e77b 1125void
42d0e0b7 1126Perl_sv_upgrade(pTHX_ register SV *sv, svtype new_type)
cac9b346 1127{
97aff369 1128 dVAR;
bd81e77b
NC
1129 void* old_body;
1130 void* new_body;
42d0e0b7 1131 const svtype old_type = SvTYPE(sv);
d2a0f284 1132 const struct body_details *new_type_details;
bd81e77b
NC
1133 const struct body_details *const old_type_details
1134 = bodies_by_type + old_type;
cac9b346 1135
bd81e77b
NC
1136 if (new_type != SVt_PV && SvIsCOW(sv)) {
1137 sv_force_normal_flags(sv, 0);
1138 }
cac9b346 1139
bd81e77b
NC
1140 if (old_type == new_type)
1141 return;
cac9b346 1142
bd81e77b
NC
1143 if (old_type > new_type)
1144 Perl_croak(aTHX_ "sv_upgrade from type %d down to type %d",
1145 (int)old_type, (int)new_type);
cac9b346 1146
cac9b346 1147
bd81e77b 1148 old_body = SvANY(sv);
de042e1d 1149
bd81e77b
NC
1150 /* Copying structures onto other structures that have been neatly zeroed
1151 has a subtle gotcha. Consider XPVMG
cac9b346 1152
bd81e77b
NC
1153 +------+------+------+------+------+-------+-------+
1154 | NV | CUR | LEN | IV | MAGIC | STASH |
1155 +------+------+------+------+------+-------+-------+
1156 0 4 8 12 16 20 24 28
645c22ef 1157
bd81e77b
NC
1158 where NVs are aligned to 8 bytes, so that sizeof that structure is
1159 actually 32 bytes long, with 4 bytes of padding at the end:
08742458 1160
bd81e77b
NC
1161 +------+------+------+------+------+-------+-------+------+
1162 | NV | CUR | LEN | IV | MAGIC | STASH | ??? |
1163 +------+------+------+------+------+-------+-------+------+
1164 0 4 8 12 16 20 24 28 32
08742458 1165
bd81e77b 1166 so what happens if you allocate memory for this structure:
30f9da9e 1167
bd81e77b
NC
1168 +------+------+------+------+------+-------+-------+------+------+...
1169 | NV | CUR | LEN | IV | MAGIC | STASH | GP | NAME |
1170 +------+------+------+------+------+-------+-------+------+------+...
1171 0 4 8 12 16 20 24 28 32 36
bfc44f79 1172
bd81e77b
NC
1173 zero it, then copy sizeof(XPVMG) bytes on top of it? Not quite what you
1174 expect, because you copy the area marked ??? onto GP. Now, ??? may have
1175 started out as zero once, but it's quite possible that it isn't. So now,
1176 rather than a nicely zeroed GP, you have it pointing somewhere random.
1177 Bugs ensue.
bfc44f79 1178
bd81e77b
NC
1179 (In fact, GP ends up pointing at a previous GP structure, because the
1180 principle cause of the padding in XPVMG getting garbage is a copy of
6c9e42f7
NC
1181 sizeof(XPVMG) bytes from a XPVGV structure in sv_unglob. Right now
1182 this happens to be moot because XPVGV has been re-ordered, with GP
1183 no longer after STASH)
30f9da9e 1184
bd81e77b
NC
1185 So we are careful and work out the size of used parts of all the
1186 structures. */
bfc44f79 1187
bd81e77b
NC
1188 switch (old_type) {
1189 case SVt_NULL:
1190 break;
1191 case SVt_IV:
1192 if (new_type < SVt_PVIV) {
1193 new_type = (new_type == SVt_NV)
1194 ? SVt_PVNV : SVt_PVIV;
bd81e77b
NC
1195 }
1196 break;
1197 case SVt_NV:
1198 if (new_type < SVt_PVNV) {
1199 new_type = SVt_PVNV;
bd81e77b
NC
1200 }
1201 break;
1202 case SVt_RV:
1203 break;
1204 case SVt_PV:
1205 assert(new_type > SVt_PV);
1206 assert(SVt_IV < SVt_PV);
1207 assert(SVt_NV < SVt_PV);
1208 break;
1209 case SVt_PVIV:
1210 break;
1211 case SVt_PVNV:
1212 break;
1213 case SVt_PVMG:
1214 /* Because the XPVMG of PL_mess_sv isn't allocated from the arena,
1215 there's no way that it can be safely upgraded, because perl.c
1216 expects to Safefree(SvANY(PL_mess_sv)) */
1217 assert(sv != PL_mess_sv);
1218 /* This flag bit is used to mean other things in other scalar types.
1219 Given that it only has meaning inside the pad, it shouldn't be set
1220 on anything that can get upgraded. */
00b1698f 1221 assert(!SvPAD_TYPED(sv));
bd81e77b
NC
1222 break;
1223 default:
1224 if (old_type_details->cant_upgrade)
c81225bc
NC
1225 Perl_croak(aTHX_ "Can't upgrade %s (%" UVuf ") to %" UVuf,
1226 sv_reftype(sv, 0), (UV) old_type, (UV) new_type);
bd81e77b 1227 }
2fa1109b 1228 new_type_details = bodies_by_type + new_type;
645c22ef 1229
bd81e77b
NC
1230 SvFLAGS(sv) &= ~SVTYPEMASK;
1231 SvFLAGS(sv) |= new_type;
932e9ff9 1232
ab4416c0
NC
1233 /* This can't happen, as SVt_NULL is <= all values of new_type, so one of
1234 the return statements above will have triggered. */
1235 assert (new_type != SVt_NULL);
bd81e77b 1236 switch (new_type) {
bd81e77b
NC
1237 case SVt_IV:
1238 assert(old_type == SVt_NULL);
1239 SvANY(sv) = (XPVIV*)((char*)&(sv->sv_u.svu_iv) - STRUCT_OFFSET(XPVIV, xiv_iv));
1240 SvIV_set(sv, 0);
1241 return;
1242 case SVt_NV:
1243 assert(old_type == SVt_NULL);
1244 SvANY(sv) = new_XNV();
1245 SvNV_set(sv, 0);
1246 return;
1247 case SVt_RV:
1248 assert(old_type == SVt_NULL);
1249 SvANY(sv) = &sv->sv_u.svu_rv;
1250 SvRV_set(sv, 0);
1251 return;
1252 case SVt_PVHV:
bd81e77b 1253 case SVt_PVAV:
d2a0f284 1254 assert(new_type_details->body_size);
c1ae03ae
NC
1255
1256#ifndef PURIFY
1257 assert(new_type_details->arena);
d2a0f284 1258 assert(new_type_details->arena_size);
c1ae03ae 1259 /* This points to the start of the allocated area. */
d2a0f284
JC
1260 new_body_inline(new_body, new_type);
1261 Zero(new_body, new_type_details->body_size, char);
c1ae03ae
NC
1262 new_body = ((char *)new_body) - new_type_details->offset;
1263#else
1264 /* We always allocated the full length item with PURIFY. To do this
1265 we fake things so that arena is false for all 16 types.. */
1266 new_body = new_NOARENAZ(new_type_details);
1267#endif
1268 SvANY(sv) = new_body;
1269 if (new_type == SVt_PVAV) {
1270 AvMAX(sv) = -1;
1271 AvFILLp(sv) = -1;
1272 AvREAL_only(sv);
1273 }
aeb18a1e 1274
bd81e77b
NC
1275 /* SVt_NULL isn't the only thing upgraded to AV or HV.
1276 The target created by newSVrv also is, and it can have magic.
1277 However, it never has SvPVX set.
1278 */
1279 if (old_type >= SVt_RV) {
1280 assert(SvPVX_const(sv) == 0);
1281 }
aeb18a1e 1282
bd81e77b 1283 if (old_type >= SVt_PVMG) {
e736a858 1284 SvMAGIC_set(sv, ((XPVMG*)old_body)->xmg_u.xmg_magic);
bd81e77b 1285 SvSTASH_set(sv, ((XPVMG*)old_body)->xmg_stash);
797c7171
NC
1286 } else {
1287 sv->sv_u.svu_array = NULL; /* or svu_hash */
bd81e77b
NC
1288 }
1289 break;
93e68bfb 1290
93e68bfb 1291
bd81e77b
NC
1292 case SVt_PVIV:
1293 /* XXX Is this still needed? Was it ever needed? Surely as there is
1294 no route from NV to PVIV, NOK can never be true */
1295 assert(!SvNOKp(sv));
1296 assert(!SvNOK(sv));
1297 case SVt_PVIO:
1298 case SVt_PVFM:
bd81e77b
NC
1299 case SVt_PVGV:
1300 case SVt_PVCV:
1301 case SVt_PVLV:
1302 case SVt_PVMG:
1303 case SVt_PVNV:
1304 case SVt_PV:
93e68bfb 1305
d2a0f284 1306 assert(new_type_details->body_size);
bd81e77b
NC
1307 /* We always allocated the full length item with PURIFY. To do this
1308 we fake things so that arena is false for all 16 types.. */
1309 if(new_type_details->arena) {
1310 /* This points to the start of the allocated area. */
d2a0f284
JC
1311 new_body_inline(new_body, new_type);
1312 Zero(new_body, new_type_details->body_size, char);
bd81e77b
NC
1313 new_body = ((char *)new_body) - new_type_details->offset;
1314 } else {
1315 new_body = new_NOARENAZ(new_type_details);
1316 }
1317 SvANY(sv) = new_body;
5e2fc214 1318
bd81e77b 1319 if (old_type_details->copy) {
f9ba3d20
NC
1320 /* There is now the potential for an upgrade from something without
1321 an offset (PVNV or PVMG) to something with one (PVCV, PVFM) */
1322 int offset = old_type_details->offset;
1323 int length = old_type_details->copy;
1324
1325 if (new_type_details->offset > old_type_details->offset) {
d4c19fe8 1326 const int difference
f9ba3d20
NC
1327 = new_type_details->offset - old_type_details->offset;
1328 offset += difference;
1329 length -= difference;
1330 }
1331 assert (length >= 0);
1332
1333 Copy((char *)old_body + offset, (char *)new_body + offset, length,
1334 char);
bd81e77b
NC
1335 }
1336
1337#ifndef NV_ZERO_IS_ALLBITS_ZERO
f2524eef 1338 /* If NV 0.0 is stores as all bits 0 then Zero() already creates a
e5ce394c
NC
1339 * correct 0.0 for us. Otherwise, if the old body didn't have an
1340 * NV slot, but the new one does, then we need to initialise the
1341 * freshly created NV slot with whatever the correct bit pattern is
1342 * for 0.0 */
1343 if (old_type_details->zero_nv && !new_type_details->zero_nv)
bd81e77b 1344 SvNV_set(sv, 0);
82048762 1345#endif
5e2fc214 1346
bd81e77b 1347 if (new_type == SVt_PVIO)
f2524eef 1348 IoPAGE_LEN(sv) = 60;
bd81e77b 1349 if (old_type < SVt_RV)
6136c704 1350 SvPV_set(sv, NULL);
bd81e77b
NC
1351 break;
1352 default:
afd78fd5
JH
1353 Perl_croak(aTHX_ "panic: sv_upgrade to unknown type %lu",
1354 (unsigned long)new_type);
bd81e77b 1355 }
73171d91 1356
d2a0f284
JC
1357 if (old_type_details->arena) {
1358 /* If there was an old body, then we need to free it.
1359 Note that there is an assumption that all bodies of types that
1360 can be upgraded came from arenas. Only the more complex non-
1361 upgradable types are allowed to be directly malloc()ed. */
bd81e77b
NC
1362#ifdef PURIFY
1363 my_safefree(old_body);
1364#else
1365 del_body((void*)((char*)old_body + old_type_details->offset),
1366 &PL_body_roots[old_type]);
1367#endif
1368 }
1369}
73171d91 1370
bd81e77b
NC
1371/*
1372=for apidoc sv_backoff
73171d91 1373
bd81e77b
NC
1374Remove any string offset. You should normally use the C<SvOOK_off> macro
1375wrapper instead.
73171d91 1376
bd81e77b 1377=cut
73171d91
NC
1378*/
1379
bd81e77b
NC
1380int
1381Perl_sv_backoff(pTHX_ register SV *sv)
1382{
96a5add6 1383 PERL_UNUSED_CONTEXT;
bd81e77b
NC
1384 assert(SvOOK(sv));
1385 assert(SvTYPE(sv) != SVt_PVHV);
1386 assert(SvTYPE(sv) != SVt_PVAV);
1387 if (SvIVX(sv)) {
1388 const char * const s = SvPVX_const(sv);
1389 SvLEN_set(sv, SvLEN(sv) + SvIVX(sv));
1390 SvPV_set(sv, SvPVX(sv) - SvIVX(sv));
1391 SvIV_set(sv, 0);
1392 Move(s, SvPVX(sv), SvCUR(sv)+1, char);
1393 }
1394 SvFLAGS(sv) &= ~SVf_OOK;
1395 return 0;
1396}
73171d91 1397
bd81e77b
NC
1398/*
1399=for apidoc sv_grow
73171d91 1400
bd81e77b
NC
1401Expands the character buffer in the SV. If necessary, uses C<sv_unref> and
1402upgrades the SV to C<SVt_PV>. Returns a pointer to the character buffer.
1403Use the C<SvGROW> wrapper instead.
93e68bfb 1404
bd81e77b
NC
1405=cut
1406*/
93e68bfb 1407
bd81e77b
NC
1408char *
1409Perl_sv_grow(pTHX_ register SV *sv, register STRLEN newlen)
1410{
1411 register char *s;
93e68bfb 1412
5db06880
NC
1413 if (PL_madskills && newlen >= 0x100000) {
1414 PerlIO_printf(Perl_debug_log,
1415 "Allocation too large: %"UVxf"\n", (UV)newlen);
1416 }
bd81e77b
NC
1417#ifdef HAS_64K_LIMIT
1418 if (newlen >= 0x10000) {
1419 PerlIO_printf(Perl_debug_log,
1420 "Allocation too large: %"UVxf"\n", (UV)newlen);
1421 my_exit(1);
1422 }
1423#endif /* HAS_64K_LIMIT */
1424 if (SvROK(sv))
1425 sv_unref(sv);
1426 if (SvTYPE(sv) < SVt_PV) {
1427 sv_upgrade(sv, SVt_PV);
1428 s = SvPVX_mutable(sv);
1429 }
1430 else if (SvOOK(sv)) { /* pv is offset? */
1431 sv_backoff(sv);
1432 s = SvPVX_mutable(sv);
1433 if (newlen > SvLEN(sv))
1434 newlen += 10 * (newlen - SvCUR(sv)); /* avoid copy each time */
1435#ifdef HAS_64K_LIMIT
1436 if (newlen >= 0x10000)
1437 newlen = 0xFFFF;
1438#endif
1439 }
1440 else
1441 s = SvPVX_mutable(sv);
aeb18a1e 1442
bd81e77b
NC
1443 if (newlen > SvLEN(sv)) { /* need more room? */
1444 newlen = PERL_STRLEN_ROUNDUP(newlen);
1445 if (SvLEN(sv) && s) {
1446#ifdef MYMALLOC
1447 const STRLEN l = malloced_size((void*)SvPVX_const(sv));
1448 if (newlen <= l) {
1449 SvLEN_set(sv, l);
1450 return s;
1451 } else
1452#endif
10edeb5d 1453 s = (char*)saferealloc(s, newlen);
bd81e77b
NC
1454 }
1455 else {
10edeb5d 1456 s = (char*)safemalloc(newlen);
bd81e77b
NC
1457 if (SvPVX_const(sv) && SvCUR(sv)) {
1458 Move(SvPVX_const(sv), s, (newlen < SvCUR(sv)) ? newlen : SvCUR(sv), char);
1459 }
1460 }
1461 SvPV_set(sv, s);
1462 SvLEN_set(sv, newlen);
1463 }
1464 return s;
1465}
aeb18a1e 1466
bd81e77b
NC
1467/*
1468=for apidoc sv_setiv
932e9ff9 1469
bd81e77b
NC
1470Copies an integer into the given SV, upgrading first if necessary.
1471Does not handle 'set' magic. See also C<sv_setiv_mg>.
463ee0b2 1472
bd81e77b
NC
1473=cut
1474*/
463ee0b2 1475
bd81e77b
NC
1476void
1477Perl_sv_setiv(pTHX_ register SV *sv, IV i)
1478{
97aff369 1479 dVAR;
bd81e77b
NC
1480 SV_CHECK_THINKFIRST_COW_DROP(sv);
1481 switch (SvTYPE(sv)) {
1482 case SVt_NULL:
1483 sv_upgrade(sv, SVt_IV);
1484 break;
1485 case SVt_NV:
1486 sv_upgrade(sv, SVt_PVNV);
1487 break;
1488 case SVt_RV:
1489 case SVt_PV:
1490 sv_upgrade(sv, SVt_PVIV);
1491 break;
463ee0b2 1492
bd81e77b
NC
1493 case SVt_PVGV:
1494 case SVt_PVAV:
1495 case SVt_PVHV:
1496 case SVt_PVCV:
1497 case SVt_PVFM:
1498 case SVt_PVIO:
1499 Perl_croak(aTHX_ "Can't coerce %s to integer in %s", sv_reftype(sv,0),
1500 OP_DESC(PL_op));
42d0e0b7 1501 default: NOOP;
bd81e77b
NC
1502 }
1503 (void)SvIOK_only(sv); /* validate number */
1504 SvIV_set(sv, i);
1505 SvTAINT(sv);
1506}
932e9ff9 1507
bd81e77b
NC
1508/*
1509=for apidoc sv_setiv_mg
d33b2eba 1510
bd81e77b 1511Like C<sv_setiv>, but also handles 'set' magic.
1c846c1f 1512
bd81e77b
NC
1513=cut
1514*/
d33b2eba 1515
bd81e77b
NC
1516void
1517Perl_sv_setiv_mg(pTHX_ register SV *sv, IV i)
1518{
1519 sv_setiv(sv,i);
1520 SvSETMAGIC(sv);
1521}
727879eb 1522
bd81e77b
NC
1523/*
1524=for apidoc sv_setuv
d33b2eba 1525
bd81e77b
NC
1526Copies an unsigned integer into the given SV, upgrading first if necessary.
1527Does not handle 'set' magic. See also C<sv_setuv_mg>.
9b94d1dd 1528
bd81e77b
NC
1529=cut
1530*/
d33b2eba 1531
bd81e77b
NC
1532void
1533Perl_sv_setuv(pTHX_ register SV *sv, UV u)
1534{
1535 /* With these two if statements:
1536 u=1.49 s=0.52 cu=72.49 cs=10.64 scripts=270 tests=20865
d33b2eba 1537
bd81e77b
NC
1538 without
1539 u=1.35 s=0.47 cu=73.45 cs=11.43 scripts=270 tests=20865
1c846c1f 1540
bd81e77b
NC
1541 If you wish to remove them, please benchmark to see what the effect is
1542 */
1543 if (u <= (UV)IV_MAX) {
1544 sv_setiv(sv, (IV)u);
1545 return;
1546 }
1547 sv_setiv(sv, 0);
1548 SvIsUV_on(sv);
1549 SvUV_set(sv, u);
1550}
d33b2eba 1551
bd81e77b
NC
1552/*
1553=for apidoc sv_setuv_mg
727879eb 1554
bd81e77b 1555Like C<sv_setuv>, but also handles 'set' magic.
9b94d1dd 1556
bd81e77b
NC
1557=cut
1558*/
5e2fc214 1559
bd81e77b
NC
1560void
1561Perl_sv_setuv_mg(pTHX_ register SV *sv, UV u)
1562{
bd81e77b
NC
1563 sv_setuv(sv,u);
1564 SvSETMAGIC(sv);
1565}
5e2fc214 1566
954c1994 1567/*
bd81e77b 1568=for apidoc sv_setnv
954c1994 1569
bd81e77b
NC
1570Copies a double into the given SV, upgrading first if necessary.
1571Does not handle 'set' magic. See also C<sv_setnv_mg>.
954c1994
GS
1572
1573=cut
1574*/
1575
63f97190 1576void
bd81e77b 1577Perl_sv_setnv(pTHX_ register SV *sv, NV num)
79072805 1578{
97aff369 1579 dVAR;
bd81e77b
NC
1580 SV_CHECK_THINKFIRST_COW_DROP(sv);
1581 switch (SvTYPE(sv)) {
79072805 1582 case SVt_NULL:
79072805 1583 case SVt_IV:
bd81e77b 1584 sv_upgrade(sv, SVt_NV);
79072805 1585 break;
ed6116ce 1586 case SVt_RV:
79072805 1587 case SVt_PV:
79072805 1588 case SVt_PVIV:
bd81e77b 1589 sv_upgrade(sv, SVt_PVNV);
79072805 1590 break;
bd4b1eb5 1591
bd4b1eb5 1592 case SVt_PVGV:
bd81e77b
NC
1593 case SVt_PVAV:
1594 case SVt_PVHV:
79072805 1595 case SVt_PVCV:
bd81e77b
NC
1596 case SVt_PVFM:
1597 case SVt_PVIO:
1598 Perl_croak(aTHX_ "Can't coerce %s to number in %s", sv_reftype(sv,0),
1599 OP_NAME(PL_op));
42d0e0b7 1600 default: NOOP;
2068cd4d 1601 }
bd81e77b
NC
1602 SvNV_set(sv, num);
1603 (void)SvNOK_only(sv); /* validate number */
1604 SvTAINT(sv);
79072805
LW
1605}
1606
645c22ef 1607/*
bd81e77b 1608=for apidoc sv_setnv_mg
645c22ef 1609
bd81e77b 1610Like C<sv_setnv>, but also handles 'set' magic.
645c22ef
DM
1611
1612=cut
1613*/
1614
bd81e77b
NC
1615void
1616Perl_sv_setnv_mg(pTHX_ register SV *sv, NV num)
79072805 1617{
bd81e77b
NC
1618 sv_setnv(sv,num);
1619 SvSETMAGIC(sv);
79072805
LW
1620}
1621
bd81e77b
NC
1622/* Print an "isn't numeric" warning, using a cleaned-up,
1623 * printable version of the offending string
1624 */
954c1994 1625
bd81e77b
NC
1626STATIC void
1627S_not_a_number(pTHX_ SV *sv)
79072805 1628{
97aff369 1629 dVAR;
bd81e77b
NC
1630 SV *dsv;
1631 char tmpbuf[64];
1632 const char *pv;
94463019
JH
1633
1634 if (DO_UTF8(sv)) {
396482e1 1635 dsv = sv_2mortal(newSVpvs(""));
94463019
JH
1636 pv = sv_uni_display(dsv, sv, 10, 0);
1637 } else {
1638 char *d = tmpbuf;
551405c4 1639 const char * const limit = tmpbuf + sizeof(tmpbuf) - 8;
94463019
JH
1640 /* each *s can expand to 4 chars + "...\0",
1641 i.e. need room for 8 chars */
ecdeb87c 1642
00b6aa41
AL
1643 const char *s = SvPVX_const(sv);
1644 const char * const end = s + SvCUR(sv);
1645 for ( ; s < end && d < limit; s++ ) {
94463019
JH
1646 int ch = *s & 0xFF;
1647 if (ch & 128 && !isPRINT_LC(ch)) {
1648 *d++ = 'M';
1649 *d++ = '-';
1650 ch &= 127;
1651 }
1652 if (ch == '\n') {
1653 *d++ = '\\';
1654 *d++ = 'n';
1655 }
1656 else if (ch == '\r') {
1657 *d++ = '\\';
1658 *d++ = 'r';
1659 }
1660 else if (ch == '\f') {
1661 *d++ = '\\';
1662 *d++ = 'f';
1663 }
1664 else if (ch == '\\') {
1665 *d++ = '\\';
1666 *d++ = '\\';
1667 }
1668 else if (ch == '\0') {
1669 *d++ = '\\';
1670 *d++ = '0';
1671 }
1672 else if (isPRINT_LC(ch))
1673 *d++ = ch;
1674 else {
1675 *d++ = '^';
1676 *d++ = toCTRL(ch);
1677 }
1678 }
1679 if (s < end) {
1680 *d++ = '.';
1681 *d++ = '.';
1682 *d++ = '.';
1683 }
1684 *d = '\0';
1685 pv = tmpbuf;
a0d0e21e 1686 }
a0d0e21e 1687
533c011a 1688 if (PL_op)
9014280d 1689 Perl_warner(aTHX_ packWARN(WARN_NUMERIC),
94463019
JH
1690 "Argument \"%s\" isn't numeric in %s", pv,
1691 OP_DESC(PL_op));
a0d0e21e 1692 else
9014280d 1693 Perl_warner(aTHX_ packWARN(WARN_NUMERIC),
94463019 1694 "Argument \"%s\" isn't numeric", pv);
a0d0e21e
LW
1695}
1696
c2988b20
NC
1697/*
1698=for apidoc looks_like_number
1699
645c22ef
DM
1700Test if the content of an SV looks like a number (or is a number).
1701C<Inf> and C<Infinity> are treated as numbers (so will not issue a
1702non-numeric warning), even if your atof() doesn't grok them.
c2988b20
NC
1703
1704=cut
1705*/
1706
1707I32
1708Perl_looks_like_number(pTHX_ SV *sv)
1709{
a3b680e6 1710 register const char *sbegin;
c2988b20
NC
1711 STRLEN len;
1712
1713 if (SvPOK(sv)) {
3f7c398e 1714 sbegin = SvPVX_const(sv);
c2988b20
NC
1715 len = SvCUR(sv);
1716 }
1717 else if (SvPOKp(sv))
83003860 1718 sbegin = SvPV_const(sv, len);
c2988b20 1719 else
e0ab1c0e 1720 return SvFLAGS(sv) & (SVf_NOK|SVp_NOK|SVf_IOK|SVp_IOK);
c2988b20
NC
1721 return grok_number(sbegin, len, NULL);
1722}
25da4f38 1723
19f6321d
NC
1724STATIC bool
1725S_glob_2number(pTHX_ GV * const gv)
180488f8
NC
1726{
1727 const U32 wasfake = SvFLAGS(gv) & SVf_FAKE;
1728 SV *const buffer = sv_newmortal();
1729
1730 /* FAKE globs can get coerced, so need to turn this off temporarily if it
1731 is on. */
1732 SvFAKE_off(gv);
1733 gv_efullname3(buffer, gv, "*");
1734 SvFLAGS(gv) |= wasfake;
1735
675c862f
AL
1736 /* We know that all GVs stringify to something that is not-a-number,
1737 so no need to test that. */
1738 if (ckWARN(WARN_NUMERIC))
1739 not_a_number(buffer);
1740 /* We just want something true to return, so that S_sv_2iuv_common
1741 can tail call us and return true. */
19f6321d 1742 return TRUE;
675c862f
AL
1743}
1744
1745STATIC char *
19f6321d 1746S_glob_2pv(pTHX_ GV * const gv, STRLEN * const len)
675c862f
AL
1747{
1748 const U32 wasfake = SvFLAGS(gv) & SVf_FAKE;
1749 SV *const buffer = sv_newmortal();
1750
1751 /* FAKE globs can get coerced, so need to turn this off temporarily if it
1752 is on. */
1753 SvFAKE_off(gv);
1754 gv_efullname3(buffer, gv, "*");
1755 SvFLAGS(gv) |= wasfake;
1756
1757 assert(SvPOK(buffer));
a6d61a6c
NC
1758 if (len) {
1759 *len = SvCUR(buffer);
1760 }
675c862f 1761 return SvPVX(buffer);
180488f8
NC
1762}
1763
25da4f38
IZ
1764/* Actually, ISO C leaves conversion of UV to IV undefined, but
1765 until proven guilty, assume that things are not that bad... */
1766
645c22ef
DM
1767/*
1768 NV_PRESERVES_UV:
1769
1770 As 64 bit platforms often have an NV that doesn't preserve all bits of
28e5dec8
JH
1771 an IV (an assumption perl has been based on to date) it becomes necessary
1772 to remove the assumption that the NV always carries enough precision to
1773 recreate the IV whenever needed, and that the NV is the canonical form.
1774 Instead, IV/UV and NV need to be given equal rights. So as to not lose
645c22ef 1775 precision as a side effect of conversion (which would lead to insanity
28e5dec8
JH
1776 and the dragon(s) in t/op/numconvert.t getting very angry) the intent is
1777 1) to distinguish between IV/UV/NV slots that have cached a valid
1778 conversion where precision was lost and IV/UV/NV slots that have a
1779 valid conversion which has lost no precision
645c22ef 1780 2) to ensure that if a numeric conversion to one form is requested that
28e5dec8
JH
1781 would lose precision, the precise conversion (or differently
1782 imprecise conversion) is also performed and cached, to prevent
1783 requests for different numeric formats on the same SV causing
1784 lossy conversion chains. (lossless conversion chains are perfectly
1785 acceptable (still))
1786
1787
1788 flags are used:
1789 SvIOKp is true if the IV slot contains a valid value
1790 SvIOK is true only if the IV value is accurate (UV if SvIOK_UV true)
1791 SvNOKp is true if the NV slot contains a valid value
1792 SvNOK is true only if the NV value is accurate
1793
1794 so
645c22ef 1795 while converting from PV to NV, check to see if converting that NV to an
28e5dec8
JH
1796 IV(or UV) would lose accuracy over a direct conversion from PV to
1797 IV(or UV). If it would, cache both conversions, return NV, but mark
1798 SV as IOK NOKp (ie not NOK).
1799
645c22ef 1800 While converting from PV to IV, check to see if converting that IV to an
28e5dec8
JH
1801 NV would lose accuracy over a direct conversion from PV to NV. If it
1802 would, cache both conversions, flag similarly.
1803
1804 Before, the SV value "3.2" could become NV=3.2 IV=3 NOK, IOK quite
1805 correctly because if IV & NV were set NV *always* overruled.
645c22ef
DM
1806 Now, "3.2" will become NV=3.2 IV=3 NOK, IOKp, because the flag's meaning
1807 changes - now IV and NV together means that the two are interchangeable:
28e5dec8 1808 SvIVX == (IV) SvNVX && SvNVX == (NV) SvIVX;
d460ef45 1809
645c22ef
DM
1810 The benefit of this is that operations such as pp_add know that if
1811 SvIOK is true for both left and right operands, then integer addition
1812 can be used instead of floating point (for cases where the result won't
1813 overflow). Before, floating point was always used, which could lead to
28e5dec8
JH
1814 loss of precision compared with integer addition.
1815
1816 * making IV and NV equal status should make maths accurate on 64 bit
1817 platforms
1818 * may speed up maths somewhat if pp_add and friends start to use
645c22ef 1819 integers when possible instead of fp. (Hopefully the overhead in
28e5dec8
JH
1820 looking for SvIOK and checking for overflow will not outweigh the
1821 fp to integer speedup)
1822 * will slow down integer operations (callers of SvIV) on "inaccurate"
1823 values, as the change from SvIOK to SvIOKp will cause a call into
1824 sv_2iv each time rather than a macro access direct to the IV slot
1825 * should speed up number->string conversion on integers as IV is
645c22ef 1826 favoured when IV and NV are equally accurate
28e5dec8
JH
1827
1828 ####################################################################
645c22ef
DM
1829 You had better be using SvIOK_notUV if you want an IV for arithmetic:
1830 SvIOK is true if (IV or UV), so you might be getting (IV)SvUV.
1831 On the other hand, SvUOK is true iff UV.
28e5dec8
JH
1832 ####################################################################
1833
645c22ef 1834 Your mileage will vary depending your CPU's relative fp to integer
28e5dec8
JH
1835 performance ratio.
1836*/
1837
1838#ifndef NV_PRESERVES_UV
645c22ef
DM
1839# define IS_NUMBER_UNDERFLOW_IV 1
1840# define IS_NUMBER_UNDERFLOW_UV 2
1841# define IS_NUMBER_IV_AND_UV 2
1842# define IS_NUMBER_OVERFLOW_IV 4
1843# define IS_NUMBER_OVERFLOW_UV 5
1844
1845/* sv_2iuv_non_preserve(): private routine for use by sv_2iv() and sv_2uv() */
28e5dec8
JH
1846
1847/* For sv_2nv these three cases are "SvNOK and don't bother casting" */
1848STATIC int
645c22ef 1849S_sv_2iuv_non_preserve(pTHX_ register SV *sv, I32 numtype)
28e5dec8 1850{
97aff369 1851 dVAR;
b57a0404 1852 PERL_UNUSED_ARG(numtype); /* Used only under DEBUGGING? */
3f7c398e 1853 DEBUG_c(PerlIO_printf(Perl_debug_log,"sv_2iuv_non '%s', IV=0x%"UVxf" NV=%"NVgf" inttype=%"UVXf"\n", SvPVX_const(sv), SvIVX(sv), SvNVX(sv), (UV)numtype));
28e5dec8
JH
1854 if (SvNVX(sv) < (NV)IV_MIN) {
1855 (void)SvIOKp_on(sv);
1856 (void)SvNOK_on(sv);
45977657 1857 SvIV_set(sv, IV_MIN);
28e5dec8
JH
1858 return IS_NUMBER_UNDERFLOW_IV;
1859 }
1860 if (SvNVX(sv) > (NV)UV_MAX) {
1861 (void)SvIOKp_on(sv);
1862 (void)SvNOK_on(sv);
1863 SvIsUV_on(sv);
607fa7f2 1864 SvUV_set(sv, UV_MAX);
28e5dec8
JH
1865 return IS_NUMBER_OVERFLOW_UV;
1866 }
c2988b20
NC
1867 (void)SvIOKp_on(sv);
1868 (void)SvNOK_on(sv);
1869 /* Can't use strtol etc to convert this string. (See truth table in
1870 sv_2iv */
1871 if (SvNVX(sv) <= (UV)IV_MAX) {
45977657 1872 SvIV_set(sv, I_V(SvNVX(sv)));
c2988b20
NC
1873 if ((NV)(SvIVX(sv)) == SvNVX(sv)) {
1874 SvIOK_on(sv); /* Integer is precise. NOK, IOK */
1875 } else {
1876 /* Integer is imprecise. NOK, IOKp */
1877 }
1878 return SvNVX(sv) < 0 ? IS_NUMBER_UNDERFLOW_UV : IS_NUMBER_IV_AND_UV;
1879 }
1880 SvIsUV_on(sv);
607fa7f2 1881 SvUV_set(sv, U_V(SvNVX(sv)));
c2988b20
NC
1882 if ((NV)(SvUVX(sv)) == SvNVX(sv)) {
1883 if (SvUVX(sv) == UV_MAX) {
1884 /* As we know that NVs don't preserve UVs, UV_MAX cannot
1885 possibly be preserved by NV. Hence, it must be overflow.
1886 NOK, IOKp */
1887 return IS_NUMBER_OVERFLOW_UV;
1888 }
1889 SvIOK_on(sv); /* Integer is precise. NOK, UOK */
1890 } else {
1891 /* Integer is imprecise. NOK, IOKp */
28e5dec8 1892 }
c2988b20 1893 return IS_NUMBER_OVERFLOW_IV;
28e5dec8 1894}
645c22ef
DM
1895#endif /* !NV_PRESERVES_UV*/
1896
af359546
NC
1897STATIC bool
1898S_sv_2iuv_common(pTHX_ SV *sv) {
97aff369 1899 dVAR;
af359546 1900 if (SvNOKp(sv)) {
28e5dec8
JH
1901 /* erm. not sure. *should* never get NOKp (without NOK) from sv_2nv
1902 * without also getting a cached IV/UV from it at the same time
1903 * (ie PV->NV conversion should detect loss of accuracy and cache
af359546
NC
1904 * IV or UV at same time to avoid this. */
1905 /* IV-over-UV optimisation - choose to cache IV if possible */
25da4f38
IZ
1906
1907 if (SvTYPE(sv) == SVt_NV)
1908 sv_upgrade(sv, SVt_PVNV);
1909
28e5dec8
JH
1910 (void)SvIOKp_on(sv); /* Must do this first, to clear any SvOOK */
1911 /* < not <= as for NV doesn't preserve UV, ((NV)IV_MAX+1) will almost
1912 certainly cast into the IV range at IV_MAX, whereas the correct
1913 answer is the UV IV_MAX +1. Hence < ensures that dodgy boundary
1914 cases go to UV */
cab190d4
JD
1915#if defined(NAN_COMPARE_BROKEN) && defined(Perl_isnan)
1916 if (Perl_isnan(SvNVX(sv))) {
1917 SvUV_set(sv, 0);
1918 SvIsUV_on(sv);
fdbe6d7c 1919 return FALSE;
cab190d4 1920 }
cab190d4 1921#endif
28e5dec8 1922 if (SvNVX(sv) < (NV)IV_MAX + 0.5) {
45977657 1923 SvIV_set(sv, I_V(SvNVX(sv)));
28e5dec8
JH
1924 if (SvNVX(sv) == (NV) SvIVX(sv)
1925#ifndef NV_PRESERVES_UV
1926 && (((UV)1 << NV_PRESERVES_UV_BITS) >
1927 (UV)(SvIVX(sv) > 0 ? SvIVX(sv) : -SvIVX(sv)))
1928 /* Don't flag it as "accurately an integer" if the number
1929 came from a (by definition imprecise) NV operation, and
1930 we're outside the range of NV integer precision */
1931#endif
1932 ) {
1933 SvIOK_on(sv); /* Can this go wrong with rounding? NWC */
1934 DEBUG_c(PerlIO_printf(Perl_debug_log,
7234c960 1935 "0x%"UVxf" iv(%"NVgf" => %"IVdf") (precise)\n",
28e5dec8
JH
1936 PTR2UV(sv),
1937 SvNVX(sv),
1938 SvIVX(sv)));
1939
1940 } else {
1941 /* IV not precise. No need to convert from PV, as NV
1942 conversion would already have cached IV if it detected
1943 that PV->IV would be better than PV->NV->IV
1944 flags already correct - don't set public IOK. */
1945 DEBUG_c(PerlIO_printf(Perl_debug_log,
7234c960 1946 "0x%"UVxf" iv(%"NVgf" => %"IVdf") (imprecise)\n",
28e5dec8
JH
1947 PTR2UV(sv),
1948 SvNVX(sv),
1949 SvIVX(sv)));
1950 }
1951 /* Can the above go wrong if SvIVX == IV_MIN and SvNVX < IV_MIN,
1952 but the cast (NV)IV_MIN rounds to a the value less (more
1953 negative) than IV_MIN which happens to be equal to SvNVX ??
1954 Analogous to 0xFFFFFFFFFFFFFFFF rounding up to NV (2**64) and
1955 NV rounding back to 0xFFFFFFFFFFFFFFFF, so UVX == UV(NVX) and
1956 (NV)UVX == NVX are both true, but the values differ. :-(
1957 Hopefully for 2s complement IV_MIN is something like
1958 0x8000000000000000 which will be exact. NWC */
d460ef45 1959 }
25da4f38 1960 else {
607fa7f2 1961 SvUV_set(sv, U_V(SvNVX(sv)));
28e5dec8
JH
1962 if (
1963 (SvNVX(sv) == (NV) SvUVX(sv))
1964#ifndef NV_PRESERVES_UV
1965 /* Make sure it's not 0xFFFFFFFFFFFFFFFF */
1966 /*&& (SvUVX(sv) != UV_MAX) irrelevant with code below */
1967 && (((UV)1 << NV_PRESERVES_UV_BITS) > SvUVX(sv))
1968 /* Don't flag it as "accurately an integer" if the number
1969 came from a (by definition imprecise) NV operation, and
1970 we're outside the range of NV integer precision */
1971#endif
1972 )
1973 SvIOK_on(sv);
25da4f38 1974 SvIsUV_on(sv);
1c846c1f 1975 DEBUG_c(PerlIO_printf(Perl_debug_log,
57def98f 1976 "0x%"UVxf" 2iv(%"UVuf" => %"IVdf") (as unsigned)\n",
56431972 1977 PTR2UV(sv),
57def98f
JH
1978 SvUVX(sv),
1979 SvUVX(sv)));
25da4f38 1980 }
748a9306
LW
1981 }
1982 else if (SvPOKp(sv) && SvLEN(sv)) {
c2988b20 1983 UV value;
504618e9 1984 const int numtype = grok_number(SvPVX_const(sv), SvCUR(sv), &value);
af359546 1985 /* We want to avoid a possible problem when we cache an IV/ a UV which
25da4f38 1986 may be later translated to an NV, and the resulting NV is not
c2988b20
NC
1987 the same as the direct translation of the initial string
1988 (eg 123.456 can shortcut to the IV 123 with atol(), but we must
1989 be careful to ensure that the value with the .456 is around if the
1990 NV value is requested in the future).
1c846c1f 1991
af359546 1992 This means that if we cache such an IV/a UV, we need to cache the
25da4f38 1993 NV as well. Moreover, we trade speed for space, and do not
28e5dec8 1994 cache the NV if we are sure it's not needed.
25da4f38 1995 */
16b7a9a4 1996
c2988b20
NC
1997 /* SVt_PVNV is one higher than SVt_PVIV, hence this order */
1998 if ((numtype & (IS_NUMBER_IN_UV | IS_NUMBER_NOT_INT))
1999 == IS_NUMBER_IN_UV) {
5e045b90 2000 /* It's definitely an integer, only upgrade to PVIV */
28e5dec8
JH
2001 if (SvTYPE(sv) < SVt_PVIV)
2002 sv_upgrade(sv, SVt_PVIV);
f7bbb42a 2003 (void)SvIOK_on(sv);
c2988b20
NC
2004 } else if (SvTYPE(sv) < SVt_PVNV)
2005 sv_upgrade(sv, SVt_PVNV);
28e5dec8 2006
f2524eef 2007 /* If NVs preserve UVs then we only use the UV value if we know that
c2988b20
NC
2008 we aren't going to call atof() below. If NVs don't preserve UVs
2009 then the value returned may have more precision than atof() will
2010 return, even though value isn't perfectly accurate. */
2011 if ((numtype & (IS_NUMBER_IN_UV
2012#ifdef NV_PRESERVES_UV
2013 | IS_NUMBER_NOT_INT
2014#endif
2015 )) == IS_NUMBER_IN_UV) {
2016 /* This won't turn off the public IOK flag if it was set above */
2017 (void)SvIOKp_on(sv);
2018
2019 if (!(numtype & IS_NUMBER_NEG)) {
2020 /* positive */;
2021 if (value <= (UV)IV_MAX) {
45977657 2022 SvIV_set(sv, (IV)value);
c2988b20 2023 } else {
af359546 2024 /* it didn't overflow, and it was positive. */
607fa7f2 2025 SvUV_set(sv, value);
c2988b20
NC
2026 SvIsUV_on(sv);
2027 }
2028 } else {
2029 /* 2s complement assumption */
2030 if (value <= (UV)IV_MIN) {
45977657 2031 SvIV_set(sv, -(IV)value);
c2988b20
NC
2032 } else {
2033 /* Too negative for an IV. This is a double upgrade, but
d1be9408 2034 I'm assuming it will be rare. */
c2988b20
NC
2035 if (SvTYPE(sv) < SVt_PVNV)
2036 sv_upgrade(sv, SVt_PVNV);
2037 SvNOK_on(sv);
2038 SvIOK_off(sv);
2039 SvIOKp_on(sv);
9d6ce603 2040 SvNV_set(sv, -(NV)value);
45977657 2041 SvIV_set(sv, IV_MIN);
c2988b20
NC
2042 }
2043 }
2044 }
2045 /* For !NV_PRESERVES_UV and IS_NUMBER_IN_UV and IS_NUMBER_NOT_INT we
2046 will be in the previous block to set the IV slot, and the next
2047 block to set the NV slot. So no else here. */
2048
2049 if ((numtype & (IS_NUMBER_IN_UV | IS_NUMBER_NOT_INT))
2050 != IS_NUMBER_IN_UV) {
2051 /* It wasn't an (integer that doesn't overflow the UV). */
3f7c398e 2052 SvNV_set(sv, Atof(SvPVX_const(sv)));
28e5dec8 2053
c2988b20
NC
2054 if (! numtype && ckWARN(WARN_NUMERIC))
2055 not_a_number(sv);
28e5dec8 2056
65202027 2057#if defined(USE_LONG_DOUBLE)
c2988b20
NC
2058 DEBUG_c(PerlIO_printf(Perl_debug_log, "0x%"UVxf" 2iv(%" PERL_PRIgldbl ")\n",
2059 PTR2UV(sv), SvNVX(sv)));
65202027 2060#else
1779d84d 2061 DEBUG_c(PerlIO_printf(Perl_debug_log, "0x%"UVxf" 2iv(%"NVgf")\n",
c2988b20 2062 PTR2UV(sv), SvNVX(sv)));
65202027 2063#endif
28e5dec8 2064
28e5dec8 2065#ifdef NV_PRESERVES_UV
af359546
NC
2066 (void)SvIOKp_on(sv);
2067 (void)SvNOK_on(sv);
2068 if (SvNVX(sv) < (NV)IV_MAX + 0.5) {
2069 SvIV_set(sv, I_V(SvNVX(sv)));
2070 if ((NV)(SvIVX(sv)) == SvNVX(sv)) {
2071 SvIOK_on(sv);
2072 } else {
6f207bd3 2073 NOOP; /* Integer is imprecise. NOK, IOKp */
af359546
NC
2074 }
2075 /* UV will not work better than IV */
2076 } else {
2077 if (SvNVX(sv) > (NV)UV_MAX) {
2078 SvIsUV_on(sv);
2079 /* Integer is inaccurate. NOK, IOKp, is UV */
2080 SvUV_set(sv, UV_MAX);
af359546
NC
2081 } else {
2082 SvUV_set(sv, U_V(SvNVX(sv)));
2083 /* 0xFFFFFFFFFFFFFFFF not an issue in here, NVs
2084 NV preservse UV so can do correct comparison. */
2085 if ((NV)(SvUVX(sv)) == SvNVX(sv)) {
2086 SvIOK_on(sv);
af359546 2087 } else {
6f207bd3 2088 NOOP; /* Integer is imprecise. NOK, IOKp, is UV */
af359546
NC
2089 }
2090 }
4b0c9573 2091 SvIsUV_on(sv);
af359546 2092 }
28e5dec8 2093#else /* NV_PRESERVES_UV */
c2988b20
NC
2094 if ((numtype & (IS_NUMBER_IN_UV | IS_NUMBER_NOT_INT))
2095 == (IS_NUMBER_IN_UV | IS_NUMBER_NOT_INT)) {
af359546 2096 /* The IV/UV slot will have been set from value returned by
c2988b20
NC
2097 grok_number above. The NV slot has just been set using
2098 Atof. */
560b0c46 2099 SvNOK_on(sv);
c2988b20
NC
2100 assert (SvIOKp(sv));
2101 } else {
2102 if (((UV)1 << NV_PRESERVES_UV_BITS) >
2103 U_V(SvNVX(sv) > 0 ? SvNVX(sv) : -SvNVX(sv))) {
2104 /* Small enough to preserve all bits. */
2105 (void)SvIOKp_on(sv);
2106 SvNOK_on(sv);
45977657 2107 SvIV_set(sv, I_V(SvNVX(sv)));
c2988b20
NC
2108 if ((NV)(SvIVX(sv)) == SvNVX(sv))
2109 SvIOK_on(sv);
2110 /* Assumption: first non-preserved integer is < IV_MAX,
2111 this NV is in the preserved range, therefore: */
2112 if (!(U_V(SvNVX(sv) > 0 ? SvNVX(sv) : -SvNVX(sv))
2113 < (UV)IV_MAX)) {
32fdb065 2114 Perl_croak(aTHX_ "sv_2iv assumed (U_V(fabs((double)SvNVX(sv))) < (UV)IV_MAX) but SvNVX(sv)=%"NVgf" U_V is 0x%"UVxf", IV_MAX is 0x%"UVxf"\n", SvNVX(sv), U_V(SvNVX(sv)), (UV)IV_MAX);
c2988b20
NC
2115 }
2116 } else {
2117 /* IN_UV NOT_INT
2118 0 0 already failed to read UV.
2119 0 1 already failed to read UV.
2120 1 0 you won't get here in this case. IV/UV
2121 slot set, public IOK, Atof() unneeded.
2122 1 1 already read UV.
2123 so there's no point in sv_2iuv_non_preserve() attempting
2124 to use atol, strtol, strtoul etc. */
40a17c4c 2125 sv_2iuv_non_preserve (sv, numtype);
c2988b20
NC
2126 }
2127 }
28e5dec8 2128#endif /* NV_PRESERVES_UV */
25da4f38 2129 }
af359546
NC
2130 }
2131 else {
675c862f 2132 if (isGV_with_GP(sv))
a0933d07 2133 return glob_2number((GV *)sv);
180488f8 2134
af359546
NC
2135 if (!(SvFLAGS(sv) & SVs_PADTMP)) {
2136 if (!PL_localizing && ckWARN(WARN_UNINITIALIZED))
2137 report_uninit(sv);
2138 }
25da4f38
IZ
2139 if (SvTYPE(sv) < SVt_IV)
2140 /* Typically the caller expects that sv_any is not NULL now. */
2141 sv_upgrade(sv, SVt_IV);
af359546
NC
2142 /* Return 0 from the caller. */
2143 return TRUE;
2144 }
2145 return FALSE;
2146}
2147
2148/*
2149=for apidoc sv_2iv_flags
2150
2151Return the integer value of an SV, doing any necessary string
2152conversion. If flags includes SV_GMAGIC, does an mg_get() first.
2153Normally used via the C<SvIV(sv)> and C<SvIVx(sv)> macros.
2154
2155=cut
2156*/
2157
2158IV
2159Perl_sv_2iv_flags(pTHX_ register SV *sv, I32 flags)
2160{
97aff369 2161 dVAR;
af359546 2162 if (!sv)
a0d0e21e 2163 return 0;
cecf5685
NC
2164 if (SvGMAGICAL(sv) || (SvTYPE(sv) == SVt_PVGV && SvVALID(sv))) {
2165 /* FBMs use the same flag bit as SVf_IVisUV, so must let them
50caf62e
NC
2166 cache IVs just in case. In practice it seems that they never
2167 actually anywhere accessible by user Perl code, let alone get used
2168 in anything other than a string context. */
af359546
NC
2169 if (flags & SV_GMAGIC)
2170 mg_get(sv);
2171 if (SvIOKp(sv))
2172 return SvIVX(sv);
2173 if (SvNOKp(sv)) {
2174 return I_V(SvNVX(sv));
2175 }
71c558c3
NC
2176 if (SvPOKp(sv) && SvLEN(sv)) {
2177 UV value;
2178 const int numtype
2179 = grok_number(SvPVX_const(sv), SvCUR(sv), &value);
2180
2181 if ((numtype & (IS_NUMBER_IN_UV | IS_NUMBER_NOT_INT))
2182 == IS_NUMBER_IN_UV) {
2183 /* It's definitely an integer */
2184 if (numtype & IS_NUMBER_NEG) {
2185 if (value < (UV)IV_MIN)
2186 return -(IV)value;
2187 } else {
2188 if (value < (UV)IV_MAX)
2189 return (IV)value;
2190 }
2191 }
2192 if (!numtype) {
2193 if (ckWARN(WARN_NUMERIC))
2194 not_a_number(sv);
2195 }
2196 return I_V(Atof(SvPVX_const(sv)));
2197 }
1c7ff15e
NC
2198 if (SvROK(sv)) {
2199 goto return_rok;
af359546 2200 }
1c7ff15e
NC
2201 assert(SvTYPE(sv) >= SVt_PVMG);
2202 /* This falls through to the report_uninit inside S_sv_2iuv_common. */
4cb1ec55 2203 } else if (SvTHINKFIRST(sv)) {
af359546 2204 if (SvROK(sv)) {
1c7ff15e 2205 return_rok:
af359546
NC
2206 if (SvAMAGIC(sv)) {
2207 SV * const tmpstr=AMG_CALLun(sv,numer);
2208 if (tmpstr && (!SvROK(tmpstr) || (SvRV(tmpstr) != SvRV(sv)))) {
2209 return SvIV(tmpstr);
2210 }
2211 }
2212 return PTR2IV(SvRV(sv));
2213 }
2214 if (SvIsCOW(sv)) {
2215 sv_force_normal_flags(sv, 0);
2216 }
2217 if (SvREADONLY(sv) && !SvOK(sv)) {
2218 if (ckWARN(WARN_UNINITIALIZED))
2219 report_uninit(sv);
2220 return 0;
2221 }
2222 }
2223 if (!SvIOKp(sv)) {
2224 if (S_sv_2iuv_common(aTHX_ sv))
2225 return 0;
79072805 2226 }
1d7c1841
GS
2227 DEBUG_c(PerlIO_printf(Perl_debug_log, "0x%"UVxf" 2iv(%"IVdf")\n",
2228 PTR2UV(sv),SvIVX(sv)));
25da4f38 2229 return SvIsUV(sv) ? (IV)SvUVX(sv) : SvIVX(sv);
79072805
LW
2230}
2231
645c22ef 2232/*
891f9566 2233=for apidoc sv_2uv_flags
645c22ef
DM
2234
2235Return the unsigned integer value of an SV, doing any necessary string
891f9566
YST
2236conversion. If flags includes SV_GMAGIC, does an mg_get() first.
2237Normally used via the C<SvUV(sv)> and C<SvUVx(sv)> macros.
645c22ef
DM
2238
2239=cut
2240*/
2241
ff68c719 2242UV
891f9566 2243Perl_sv_2uv_flags(pTHX_ register SV *sv, I32 flags)
ff68c719 2244{
97aff369 2245 dVAR;
ff68c719
PP
2246 if (!sv)
2247 return 0;
cecf5685
NC
2248 if (SvGMAGICAL(sv) || (SvTYPE(sv) == SVt_PVGV && SvVALID(sv))) {
2249 /* FBMs use the same flag bit as SVf_IVisUV, so must let them
50caf62e 2250 cache IVs just in case. */
891f9566
YST
2251 if (flags & SV_GMAGIC)
2252 mg_get(sv);
ff68c719
PP
2253 if (SvIOKp(sv))
2254 return SvUVX(sv);
2255 if (SvNOKp(sv))
2256 return U_V(SvNVX(sv));
71c558c3
NC
2257 if (SvPOKp(sv) && SvLEN(sv)) {
2258 UV value;
2259 const int numtype
2260 = grok_number(SvPVX_const(sv), SvCUR(sv), &value);
2261
2262 if ((numtype & (IS_NUMBER_IN_UV | IS_NUMBER_NOT_INT))
2263 == IS_NUMBER_IN_UV) {
2264 /* It's definitely an integer */
2265 if (!(numtype & IS_NUMBER_NEG))
2266 return value;
2267 }
2268 if (!numtype) {
2269 if (ckWARN(WARN_NUMERIC))
2270 not_a_number(sv);
2271 }
2272 return U_V(Atof(SvPVX_const(sv)));
2273 }
1c7ff15e
NC
2274 if (SvROK(sv)) {
2275 goto return_rok;
3fe9a6f1 2276 }
1c7ff15e
NC
2277 assert(SvTYPE(sv) >= SVt_PVMG);
2278 /* This falls through to the report_uninit inside S_sv_2iuv_common. */
4cb1ec55 2279 } else if (SvTHINKFIRST(sv)) {
ff68c719 2280 if (SvROK(sv)) {
1c7ff15e 2281 return_rok:
deb46114
NC
2282 if (SvAMAGIC(sv)) {
2283 SV *const tmpstr = AMG_CALLun(sv,numer);
2284 if (tmpstr && (!SvROK(tmpstr) || (SvRV(tmpstr) != SvRV(sv)))) {
2285 return SvUV(tmpstr);
2286 }
2287 }
2288 return PTR2UV(SvRV(sv));
ff68c719 2289 }
765f542d
NC
2290 if (SvIsCOW(sv)) {
2291 sv_force_normal_flags(sv, 0);
8a818333 2292 }
0336b60e 2293 if (SvREADONLY(sv) && !SvOK(sv)) {
0336b60e 2294 if (ckWARN(WARN_UNINITIALIZED))
29489e7c 2295 report_uninit(sv);
ff68c719
PP
2296 return 0;
2297 }
2298 }
af359546
NC
2299 if (!SvIOKp(sv)) {
2300 if (S_sv_2iuv_common(aTHX_ sv))
2301 return 0;
ff68c719 2302 }
25da4f38 2303
1d7c1841
GS
2304 DEBUG_c(PerlIO_printf(Perl_debug_log, "0x%"UVxf" 2uv(%"UVuf")\n",
2305 PTR2UV(sv),SvUVX(sv)));
25da4f38 2306 return SvIsUV(sv) ? SvUVX(sv) : (UV)SvIVX(sv);
ff68c719
PP
2307}
2308
645c22ef
DM
2309/*
2310=for apidoc sv_2nv
2311
2312Return the num value of an SV, doing any necessary string or integer
2313conversion, magic etc. Normally used via the C<SvNV(sv)> and C<SvNVx(sv)>
2314macros.
2315
2316=cut
2317*/
2318
65202027 2319NV
864dbfa3 2320Perl_sv_2nv(pTHX_ register SV *sv)
79072805 2321{
97aff369 2322 dVAR;
79072805
LW
2323 if (!sv)
2324 return 0.0;
cecf5685
NC
2325 if (SvGMAGICAL(sv) || (SvTYPE(sv) == SVt_PVGV && SvVALID(sv))) {
2326 /* FBMs use the same flag bit as SVf_IVisUV, so must let them
50caf62e 2327 cache IVs just in case. */
463ee0b2
LW
2328 mg_get(sv);
2329 if (SvNOKp(sv))
2330 return SvNVX(sv);
0aa395f8 2331 if ((SvPOKp(sv) && SvLEN(sv)) && !SvIOKp(sv)) {
041457d9 2332 if (!SvIOKp(sv) && ckWARN(WARN_NUMERIC) &&
504618e9 2333 !grok_number(SvPVX_const(sv), SvCUR(sv), NULL))
a0d0e21e 2334 not_a_number(sv);
3f7c398e 2335 return Atof(SvPVX_const(sv));
a0d0e21e 2336 }
25da4f38 2337 if (SvIOKp(sv)) {
1c846c1f 2338 if (SvIsUV(sv))
65202027 2339 return (NV)SvUVX(sv);
25da4f38 2340 else
65202027 2341 return (NV)SvIVX(sv);
47a72cb8
NC
2342 }
2343 if (SvROK(sv)) {
2344 goto return_rok;
2345 }
2346 assert(SvTYPE(sv) >= SVt_PVMG);
2347 /* This falls through to the report_uninit near the end of the
2348 function. */
2349 } else if (SvTHINKFIRST(sv)) {
a0d0e21e 2350 if (SvROK(sv)) {
47a72cb8 2351 return_rok:
deb46114
NC
2352 if (SvAMAGIC(sv)) {
2353 SV *const tmpstr = AMG_CALLun(sv,numer);
2354 if (tmpstr && (!SvROK(tmpstr) || (SvRV(tmpstr) != SvRV(sv)))) {
2355 return SvNV(tmpstr);
2356 }
2357 }
2358 return PTR2NV(SvRV(sv));
a0d0e21e 2359 }
765f542d
NC
2360 if (SvIsCOW(sv)) {
2361 sv_force_normal_flags(sv, 0);
8a818333 2362 }
0336b60e 2363 if (SvREADONLY(sv) && !SvOK(sv)) {
599cee73 2364 if (ckWARN(WARN_UNINITIALIZED))
29489e7c 2365 report_uninit(sv);
ed6116ce
LW
2366 return 0.0;
2367 }
79072805
LW
2368 }
2369 if (SvTYPE(sv) < SVt_NV) {
7e25a7e9
NC
2370 /* The logic to use SVt_PVNV if necessary is in sv_upgrade. */
2371 sv_upgrade(sv, SVt_NV);
906f284f 2372#ifdef USE_LONG_DOUBLE
097ee67d 2373 DEBUG_c({
f93f4e46 2374 STORE_NUMERIC_LOCAL_SET_STANDARD();
1d7c1841
GS
2375 PerlIO_printf(Perl_debug_log,
2376 "0x%"UVxf" num(%" PERL_PRIgldbl ")\n",
2377 PTR2UV(sv), SvNVX(sv));
572bbb43
GS
2378 RESTORE_NUMERIC_LOCAL();
2379 });
65202027 2380#else
572bbb43 2381 DEBUG_c({
f93f4e46 2382 STORE_NUMERIC_LOCAL_SET_STANDARD();
1779d84d 2383 PerlIO_printf(Perl_debug_log, "0x%"UVxf" num(%"NVgf")\n",
1d7c1841 2384 PTR2UV(sv), SvNVX(sv));
097ee67d
JH
2385 RESTORE_NUMERIC_LOCAL();
2386 });
572bbb43 2387#endif
79072805
LW
2388 }
2389 else if (SvTYPE(sv) < SVt_PVNV)
2390 sv_upgrade(sv, SVt_PVNV);
59d8ce62
NC
2391 if (SvNOKp(sv)) {
2392 return SvNVX(sv);
61604483 2393 }
59d8ce62 2394 if (SvIOKp(sv)) {
9d6ce603 2395 SvNV_set(sv, SvIsUV(sv) ? (NV)SvUVX(sv) : (NV)SvIVX(sv));
28e5dec8
JH
2396#ifdef NV_PRESERVES_UV
2397 SvNOK_on(sv);
2398#else
2399 /* Only set the public NV OK flag if this NV preserves the IV */
2400 /* Check it's not 0xFFFFFFFFFFFFFFFF */
2401 if (SvIsUV(sv) ? ((SvUVX(sv) != UV_MAX)&&(SvUVX(sv) == U_V(SvNVX(sv))))
2402 : (SvIVX(sv) == I_V(SvNVX(sv))))
2403 SvNOK_on(sv);
2404 else
2405 SvNOKp_on(sv);
2406#endif
93a17b20 2407 }
748a9306 2408 else if (SvPOKp(sv) && SvLEN(sv)) {
c2988b20 2409 UV value;
3f7c398e 2410 const int numtype = grok_number(SvPVX_const(sv), SvCUR(sv), &value);
041457d9 2411 if (!SvIOKp(sv) && !numtype && ckWARN(WARN_NUMERIC))
a0d0e21e 2412 not_a_number(sv);
28e5dec8 2413#ifdef NV_PRESERVES_UV
c2988b20
NC
2414 if ((numtype & (IS_NUMBER_IN_UV | IS_NUMBER_NOT_INT))
2415 == IS_NUMBER_IN_UV) {
5e045b90 2416 /* It's definitely an integer */
9d6ce603 2417 SvNV_set(sv, (numtype & IS_NUMBER_NEG) ? -(NV)value : (NV)value);
c2988b20 2418 } else
3f7c398e 2419 SvNV_set(sv, Atof(SvPVX_const(sv)));
28e5dec8
JH
2420 SvNOK_on(sv);
2421#else
3f7c398e 2422 SvNV_set(sv, Atof(SvPVX_const(sv)));
28e5dec8
JH
2423 /* Only set the public NV OK flag if this NV preserves the value in
2424 the PV at least as well as an IV/UV would.
2425 Not sure how to do this 100% reliably. */
2426 /* if that shift count is out of range then Configure's test is
2427 wonky. We shouldn't be in here with NV_PRESERVES_UV_BITS ==
2428 UV_BITS */
2429 if (((UV)1 << NV_PRESERVES_UV_BITS) >
c2988b20 2430 U_V(SvNVX(sv) > 0 ? SvNVX(sv) : -SvNVX(sv))) {
28e5dec8 2431 SvNOK_on(sv); /* Definitely small enough to preserve all bits */
c2988b20
NC
2432 } else if (!(numtype & IS_NUMBER_IN_UV)) {
2433 /* Can't use strtol etc to convert this string, so don't try.
2434 sv_2iv and sv_2uv will use the NV to convert, not the PV. */
2435 SvNOK_on(sv);
2436 } else {
2437 /* value has been set. It may not be precise. */
2438 if ((numtype & IS_NUMBER_NEG) && (value > (UV)IV_MIN)) {
2439 /* 2s complement assumption for (UV)IV_MIN */
2440 SvNOK_on(sv); /* Integer is too negative. */
2441 } else {
2442 SvNOKp_on(sv);
2443 SvIOKp_on(sv);
6fa402ec 2444
c2988b20 2445 if (numtype & IS_NUMBER_NEG) {
45977657 2446 SvIV_set(sv, -(IV)value);
c2988b20 2447 } else if (value <= (UV)IV_MAX) {
45977657 2448 SvIV_set(sv, (IV)value);
c2988b20 2449 } else {
607fa7f2 2450 SvUV_set(sv, value);
c2988b20
NC
2451 SvIsUV_on(sv);
2452 }
2453
2454 if (numtype & IS_NUMBER_NOT_INT) {
2455 /* I believe that even if the original PV had decimals,
2456 they are lost beyond the limit of the FP precision.
2457 However, neither is canonical, so both only get p
2458 flags. NWC, 2000/11/25 */
2459 /* Both already have p flags, so do nothing */
2460 } else {
66a1b24b 2461 const NV nv = SvNVX(sv);
c2988b20
NC
2462 if (SvNVX(sv) < (NV)IV_MAX + 0.5) {
2463 if (SvIVX(sv) == I_V(nv)) {
2464 SvNOK_on(sv);
c2988b20 2465 } else {
c2988b20
NC
2466 /* It had no "." so it must be integer. */
2467 }
00b6aa41 2468 SvIOK_on(sv);
c2988b20
NC
2469 } else {
2470 /* between IV_MAX and NV(UV_MAX).
2471 Could be slightly > UV_MAX */
6fa402ec 2472
c2988b20
NC
2473 if (numtype & IS_NUMBER_NOT_INT) {
2474 /* UV and NV both imprecise. */
2475 } else {
66a1b24b 2476 const UV nv_as_uv = U_V(nv);
c2988b20
NC
2477
2478 if (value == nv_as_uv && SvUVX(sv) != UV_MAX) {
2479 SvNOK_on(sv);
c2988b20 2480 }
00b6aa41 2481 SvIOK_on(sv);
c2988b20
NC
2482 }
2483 }
2484 }
2485 }
2486 }
28e5dec8 2487#endif /* NV_PRESERVES_UV */
93a17b20 2488 }
79072805 2489 else {
f7877b28 2490 if (isGV_with_GP(sv)) {
19f6321d 2491 glob_2number((GV *)sv);
180488f8
NC
2492 return 0.0;
2493 }
2494
041457d9 2495 if (!PL_localizing && !(SvFLAGS(sv) & SVs_PADTMP) && ckWARN(WARN_UNINITIALIZED))
29489e7c 2496 report_uninit(sv);
7e25a7e9
NC
2497 assert (SvTYPE(sv) >= SVt_NV);
2498 /* Typically the caller expects that sv_any is not NULL now. */
2499 /* XXX Ilya implies that this is a bug in callers that assume this
2500 and ideally should be fixed. */
a0d0e21e 2501 return 0.0;
79072805 2502 }
572bbb43 2503#if defined(USE_LONG_DOUBLE)
097ee67d 2504 DEBUG_c({
f93f4e46 2505 STORE_NUMERIC_LOCAL_SET_STANDARD();
1d7c1841
GS
2506 PerlIO_printf(Perl_debug_log, "0x%"UVxf" 2nv(%" PERL_PRIgldbl ")\n",
2507 PTR2UV(sv), SvNVX(sv));
572bbb43
GS
2508 RESTORE_NUMERIC_LOCAL();
2509 });
65202027 2510#else
572bbb43 2511 DEBUG_c({
f93f4e46 2512 STORE_NUMERIC_LOCAL_SET_STANDARD();
1779d84d 2513 PerlIO_printf(Perl_debug_log, "0x%"UVxf" 1nv(%"NVgf")\n",
1d7c1841 2514 PTR2UV(sv), SvNVX(sv));
097ee67d
JH
2515 RESTORE_NUMERIC_LOCAL();
2516 });
572bbb43 2517#endif
463ee0b2 2518 return SvNVX(sv);
79072805
LW
2519}
2520
645c22ef
DM
2521/* uiv_2buf(): private routine for use by sv_2pv_flags(): print an IV or
2522 * UV as a string towards the end of buf, and return pointers to start and
2523 * end of it.
2524 *
2525 * We assume that buf is at least TYPE_CHARS(UV) long.
2526 */
2527
864dbfa3 2528static char *
aec46f14 2529S_uiv_2buf(char *buf, IV iv, UV uv, int is_uv, char **peob)
25da4f38 2530{
25da4f38 2531 char *ptr = buf + TYPE_CHARS(UV);
823a54a3 2532 char * const ebuf = ptr;
25da4f38 2533 int sign;
25da4f38
IZ
2534
2535 if (is_uv)
2536 sign = 0;
2537 else if (iv >= 0) {
2538 uv = iv;
2539 sign = 0;
2540 } else {
2541 uv = -iv;
2542 sign = 1;
2543 }
2544 do {
eb160463 2545 *--ptr = '0' + (char)(uv % 10);
25da4f38
IZ
2546 } while (uv /= 10);
2547 if (sign)
2548 *--ptr = '-';
2549 *peob = ebuf;
2550 return ptr;
2551}
2552
645c22ef
DM
2553/*
2554=for apidoc sv_2pv_flags
2555
ff276b08 2556Returns a pointer to the string value of an SV, and sets *lp to its length.
645c22ef
DM
2557If flags includes SV_GMAGIC, does an mg_get() first. Coerces sv to a string
2558if necessary.
2559Normally invoked via the C<SvPV_flags> macro. C<sv_2pv()> and C<sv_2pv_nomg>
2560usually end up here too.
2561
2562=cut
2563*/
2564
8d6d96c1
HS
2565char *
2566Perl_sv_2pv_flags(pTHX_ register SV *sv, STRLEN *lp, I32 flags)
2567{
97aff369 2568 dVAR;
79072805 2569 register char *s;
79072805 2570
463ee0b2 2571 if (!sv) {
cdb061a3
NC
2572 if (lp)
2573 *lp = 0;
73d840c0 2574 return (char *)"";
463ee0b2 2575 }
8990e307 2576 if (SvGMAGICAL(sv)) {
8d6d96c1
HS
2577 if (flags & SV_GMAGIC)
2578 mg_get(sv);
463ee0b2 2579 if (SvPOKp(sv)) {
cdb061a3
NC
2580 if (lp)
2581 *lp = SvCUR(sv);
10516c54
NC
2582 if (flags & SV_MUTABLE_RETURN)
2583 return SvPVX_mutable(sv);
4d84ee25
NC
2584 if (flags & SV_CONST_RETURN)
2585 return (char *)SvPVX_const(sv);
463ee0b2
LW
2586 return SvPVX(sv);
2587 }
75dfc8ec
NC
2588 if (SvIOKp(sv) || SvNOKp(sv)) {
2589 char tbuf[64]; /* Must fit sprintf/Gconvert of longest IV/NV */
75dfc8ec
NC
2590 STRLEN len;
2591
2592 if (SvIOKp(sv)) {
e80fed9d 2593 len = SvIsUV(sv)
d9fad198
JH
2594 ? my_snprintf(tbuf, sizeof(tbuf), "%"UVuf, (UV)SvUVX(sv))
2595 : my_snprintf(tbuf, sizeof(tbuf), "%"IVdf, (IV)SvIVX(sv));
75dfc8ec 2596 } else {
e8ada2d0
NC
2597 Gconvert(SvNVX(sv), NV_DIG, 0, tbuf);
2598 len = strlen(tbuf);
75dfc8ec 2599 }
b5b886f0
NC
2600 assert(!SvROK(sv));
2601 {
75dfc8ec
NC
2602 dVAR;
2603
2604#ifdef FIXNEGATIVEZERO
e8ada2d0
NC
2605 if (len == 2 && tbuf[0] == '-' && tbuf[1] == '0') {
2606 tbuf[0] = '0';
2607 tbuf[1] = 0;
75dfc8ec
NC
2608 len = 1;
2609 }
2610#endif
2611 SvUPGRADE(sv, SVt_PV);
2612 if (lp)
2613 *lp = len;
2614 s = SvGROW_mutable(sv, len + 1);
2615 SvCUR_set(sv, len);
2616 SvPOKp_on(sv);
10edeb5d 2617 return (char*)memcpy(s, tbuf, len + 1);
75dfc8ec 2618 }
463ee0b2 2619 }
1c7ff15e
NC
2620 if (SvROK(sv)) {
2621 goto return_rok;
2622 }
2623 assert(SvTYPE(sv) >= SVt_PVMG);
2624 /* This falls through to the report_uninit near the end of the
2625 function. */
2626 } else if (SvTHINKFIRST(sv)) {
ed6116ce 2627 if (SvROK(sv)) {
1c7ff15e 2628 return_rok:
deb46114
NC
2629 if (SvAMAGIC(sv)) {
2630 SV *const tmpstr = AMG_CALLun(sv,string);
2631 if (tmpstr && (!SvROK(tmpstr) || (SvRV(tmpstr) != SvRV(sv)))) {
2632 /* Unwrap this: */
2633 /* char *pv = lp ? SvPV(tmpstr, *lp) : SvPV_nolen(tmpstr);
2634 */
2635
2636 char *pv;
2637 if ((SvFLAGS(tmpstr) & (SVf_POK)) == SVf_POK) {
2638 if (flags & SV_CONST_RETURN) {
2639 pv = (char *) SvPVX_const(tmpstr);
2640 } else {
2641 pv = (flags & SV_MUTABLE_RETURN)
2642 ? SvPVX_mutable(tmpstr) : SvPVX(tmpstr);
2643 }
2644 if (lp)
2645 *lp = SvCUR(tmpstr);
50adf7d2 2646 } else {
deb46114 2647 pv = sv_2pv_flags(tmpstr, lp, flags);
50adf7d2 2648 }
deb46114
NC
2649 if (SvUTF8(tmpstr))
2650 SvUTF8_on(sv);
2651 else
2652 SvUTF8_off(sv);
2653 return pv;
50adf7d2 2654 }
deb46114
NC
2655 }
2656 {
fafee734
NC
2657 STRLEN len;
2658 char *retval;
2659 char *buffer;
f9277f47 2660 MAGIC *mg;
d8eae41e
NC
2661 const SV *const referent = (SV*)SvRV(sv);
2662
2663 if (!referent) {
fafee734
NC
2664 len = 7;
2665 retval = buffer = savepvn("NULLREF", len);
042dae7a
NC
2666 } else if (SvTYPE(referent) == SVt_PVMG
2667 && ((SvFLAGS(referent) &
2668 (SVs_OBJECT|SVf_OK|SVs_GMG|SVs_SMG|SVs_RMG))
2669 == (SVs_OBJECT|SVs_SMG))
de8c5301
YO
2670 && (mg = mg_find(referent, PERL_MAGIC_qr)))
2671 {
2672 char *str = NULL;
2673 I32 haseval = 0;
60df1e07 2674 U32 flags = 0;
de8c5301
YO
2675 (str) = CALLREG_AS_STR(mg,lp,&flags,&haseval);
2676 if (flags & 1)
2677 SvUTF8_on(sv);
2678 else
2679 SvUTF8_off(sv);
2680 PL_reginterp_cnt += haseval;
2681 return str;
d8eae41e
NC
2682 } else {
2683 const char *const typestr = sv_reftype(referent, 0);
fafee734
NC
2684 const STRLEN typelen = strlen(typestr);
2685 UV addr = PTR2UV(referent);
2686 const char *stashname = NULL;
2687 STRLEN stashnamelen = 0; /* hush, gcc */
2688 const char *buffer_end;
d8eae41e 2689
d8eae41e 2690 if (SvOBJECT(referent)) {
fafee734
NC
2691 const HEK *const name = HvNAME_HEK(SvSTASH(referent));
2692
2693 if (name) {
2694 stashname = HEK_KEY(name);
2695 stashnamelen = HEK_LEN(name);
2696
2697 if (HEK_UTF8(name)) {
2698 SvUTF8_on(sv);
2699 } else {
2700 SvUTF8_off(sv);
2701 }
2702 } else {
2703 stashname = "__ANON__";
2704 stashnamelen = 8;
2705 }
2706 len = stashnamelen + 1 /* = */ + typelen + 3 /* (0x */
2707 + 2 * sizeof(UV) + 2 /* )\0 */;
2708 } else {
2709 len = typelen + 3 /* (0x */
2710 + 2 * sizeof(UV) + 2 /* )\0 */;
d8eae41e 2711 }
fafee734
NC
2712
2713 Newx(buffer, len, char);
2714 buffer_end = retval = buffer + len;
2715
2716 /* Working backwards */
2717 *--retval = '\0';
2718 *--retval = ')';
2719 do {
2720 *--retval = PL_hexdigit[addr & 15];
2721 } while (addr >>= 4);
2722 *--retval = 'x';
2723 *--retval = '0';
2724 *--retval = '(';
2725
2726 retval -= typelen;
2727 memcpy(retval, typestr, typelen);
2728
2729 if (stashname) {
2730 *--retval = '=';
2731 retval -= stashnamelen;
2732 memcpy(retval, stashname, stashnamelen);
2733 }
2734 /* retval may not neccesarily have reached the start of the
2735 buffer here. */
2736 assert (retval >= buffer);
2737
2738 len = buffer_end - retval - 1; /* -1 for that \0 */
c080367d 2739 }
042dae7a 2740 if (lp)
fafee734
NC
2741 *lp = len;
2742 SAVEFREEPV(buffer);
2743 return retval;
463ee0b2 2744 }
79072805 2745 }
0336b60e 2746 if (SvREADONLY(sv) && !SvOK(sv)) {
0336b60e 2747 if (ckWARN(WARN_UNINITIALIZED))
29489e7c 2748 report_uninit(sv);
cdb061a3
NC
2749 if (lp)
2750 *lp = 0;
73d840c0 2751 return (char *)"";
79072805 2752 }
79072805 2753 }
28e5dec8
JH
2754 if (SvIOK(sv) || ((SvIOKp(sv) && !SvNOKp(sv)))) {
2755 /* I'm assuming that if both IV and NV are equally valid then
2756 converting the IV is going to be more efficient */
e1ec3a88 2757 const U32 isUIOK = SvIsUV(sv);
28e5dec8
JH
2758 char buf[TYPE_CHARS(UV)];
2759 char *ebuf, *ptr;
2760
2761 if (SvTYPE(sv) < SVt_PVIV)
2762 sv_upgrade(sv, SVt_PVIV);
4ea1d550 2763 ptr = uiv_2buf(buf, SvIVX(sv), SvUVX(sv), isUIOK, &ebuf);
5902b6a9
NC
2764 /* inlined from sv_setpvn */
2765 SvGROW_mutable(sv, (STRLEN)(ebuf - ptr + 1));
4d84ee25 2766 Move(ptr,SvPVX_mutable(sv),ebuf - ptr,char);
28e5dec8
JH
2767 SvCUR_set(sv, ebuf - ptr);
2768 s = SvEND(sv);
2769 *s = '\0';
28e5dec8
JH
2770 }
2771 else if (SvNOKp(sv)) {
c81271c3 2772 const int olderrno = errno;
79072805
LW
2773 if (SvTYPE(sv) < SVt_PVNV)
2774 sv_upgrade(sv, SVt_PVNV);
1c846c1f 2775 /* The +20 is pure guesswork. Configure test needed. --jhi */
5902b6a9 2776 s = SvGROW_mutable(sv, NV_DIG + 20);
c81271c3 2777 /* some Xenix systems wipe out errno here */
79072805 2778#ifdef apollo
463ee0b2 2779 if (SvNVX(sv) == 0.0)
d1307786 2780 my_strlcpy(s, "0", SvLEN(sv));
79072805
LW
2781 else
2782#endif /*apollo*/
bbce6d69 2783 {
2d4389e4 2784 Gconvert(SvNVX(sv), NV_DIG, 0, s);
bbce6d69 2785 }
79072805 2786 errno = olderrno;
a0d0e21e
LW
2787#ifdef FIXNEGATIVEZERO
2788 if (*s == '-' && s[1] == '0' && !s[2])
d1307786 2789 my_strlcpy(s, "0", SvLEN(s));
a0d0e21e 2790#endif
79072805
LW
2791 while (*s) s++;
2792#ifdef hcx
2793 if (s[-1] == '.')
46fc3d4c 2794 *--s = '\0';
79072805
LW
2795#endif
2796 }
79072805 2797 else {
675c862f 2798 if (isGV_with_GP(sv))
19f6321d 2799 return glob_2pv((GV *)sv, lp);
180488f8 2800
041457d9 2801 if (!PL_localizing && !(SvFLAGS(sv) & SVs_PADTMP) && ckWARN(WARN_UNINITIALIZED))
29489e7c 2802 report_uninit(sv);
cdb061a3 2803 if (lp)
00b6aa41 2804 *lp = 0;
25da4f38
IZ
2805 if (SvTYPE(sv) < SVt_PV)
2806 /* Typically the caller expects that sv_any is not NULL now. */
2807 sv_upgrade(sv, SVt_PV);
73d840c0 2808 return (char *)"";
79072805 2809 }
cdb061a3 2810 {
823a54a3 2811 const STRLEN len = s - SvPVX_const(sv);
cdb061a3
NC
2812 if (lp)
2813 *lp = len;
2814 SvCUR_set(sv, len);
2815 }
79072805 2816 SvPOK_on(sv);
1d7c1841 2817 DEBUG_c(PerlIO_printf(Perl_debug_log, "0x%"UVxf" 2pv(%s)\n",
3f7c398e 2818 PTR2UV(sv),SvPVX_const(sv)));
4d84ee25
NC
2819 if (flags & SV_CONST_RETURN)
2820 return (char *)SvPVX_const(sv);
10516c54
NC
2821 if (flags & SV_MUTABLE_RETURN)
2822 return SvPVX_mutable(sv);
463ee0b2
LW
2823 return SvPVX(sv);
2824}
2825
645c22ef 2826/*
6050d10e
JP
2827=for apidoc sv_copypv
2828
2829Copies a stringified representation of the source SV into the
2830destination SV. Automatically performs any necessary mg_get and
54f0641b 2831coercion of numeric values into strings. Guaranteed to preserve
6050d10e 2832UTF-8 flag even from overloaded objects. Similar in nature to
54f0641b
NIS
2833sv_2pv[_flags] but operates directly on an SV instead of just the
2834string. Mostly uses sv_2pv_flags to do its work, except when that
6050d10e
JP
2835would lose the UTF-8'ness of the PV.
2836
2837=cut
2838*/
2839
2840void
2841Perl_sv_copypv(pTHX_ SV *dsv, register SV *ssv)
2842{
446eaa42 2843 STRLEN len;
53c1dcc0 2844 const char * const s = SvPV_const(ssv,len);
cb50f42d 2845 sv_setpvn(dsv,s,len);
446eaa42 2846 if (SvUTF8(ssv))
cb50f42d 2847 SvUTF8_on(dsv);
446eaa42 2848 else
cb50f42d 2849 SvUTF8_off(dsv);
6050d10e
JP
2850}
2851
2852/*
645c22ef
DM
2853=for apidoc sv_2pvbyte
2854
2855Return a pointer to the byte-encoded representation of the SV, and set *lp
1e54db1a 2856to its length. May cause the SV to be downgraded from UTF-8 as a
645c22ef
DM
2857side-effect.
2858
2859Usually accessed via the C<SvPVbyte> macro.
2860
2861=cut
2862*/
2863
7340a771
GS
2864char *
2865Perl_sv_2pvbyte(pTHX_ register SV *sv, STRLEN *lp)
2866{
0875d2fe 2867 sv_utf8_downgrade(sv,0);
97972285 2868 return lp ? SvPV(sv,*lp) : SvPV_nolen(sv);
7340a771
GS
2869}
2870
645c22ef 2871/*
035cbb0e
RGS
2872=for apidoc sv_2pvutf8
2873
2874Return a pointer to the UTF-8-encoded representation of the SV, and set *lp
2875to its length. May cause the SV to be upgraded to UTF-8 as a side-effect.
2876
2877Usually accessed via the C<SvPVutf8> macro.
2878
2879=cut
2880*/
645c22ef 2881
7340a771
GS
2882char *
2883Perl_sv_2pvutf8(pTHX_ register SV *sv, STRLEN *lp)
2884{
035cbb0e
RGS
2885 sv_utf8_upgrade(sv);
2886 return lp ? SvPV(sv,*lp) : SvPV_nolen(sv);
7340a771 2887}
1c846c1f 2888
7ee2227d 2889
645c22ef
DM
2890/*
2891=for apidoc sv_2bool
2892
2893This function is only called on magical items, and is only used by
8cf8f3d1 2894sv_true() or its macro equivalent.
645c22ef
DM
2895
2896=cut
2897*/
2898
463ee0b2 2899bool
864dbfa3 2900Perl_sv_2bool(pTHX_ register SV *sv)
463ee0b2 2901{
97aff369 2902 dVAR;
5b295bef 2903 SvGETMAGIC(sv);
463ee0b2 2904
a0d0e21e
LW
2905 if (!SvOK(sv))
2906 return 0;
2907 if (SvROK(sv)) {
fabdb6c0
AL
2908 if (SvAMAGIC(sv)) {
2909 SV * const tmpsv = AMG_CALLun(sv,bool_);
2910 if (tmpsv && (!SvROK(tmpsv) || (SvRV(tmpsv) != SvRV(sv))))
2911 return (bool)SvTRUE(tmpsv);
2912 }
2913 return SvRV(sv) != 0;
a0d0e21e 2914 }
463ee0b2 2915 if (SvPOKp(sv)) {
53c1dcc0
AL
2916 register XPV* const Xpvtmp = (XPV*)SvANY(sv);
2917 if (Xpvtmp &&
339049b0 2918 (*sv->sv_u.svu_pv > '0' ||
11343788 2919 Xpvtmp->xpv_cur > 1 ||
339049b0 2920 (Xpvtmp->xpv_cur && *sv->sv_u.svu_pv != '0')))
463ee0b2
LW
2921 return 1;
2922 else
2923 return 0;
2924 }
2925 else {
2926 if (SvIOKp(sv))
2927 return SvIVX(sv) != 0;
2928 else {
2929 if (SvNOKp(sv))
2930 return SvNVX(sv) != 0.0;
180488f8 2931 else {
f7877b28 2932 if (isGV_with_GP(sv))
180488f8
NC
2933 return TRUE;
2934 else
2935 return FALSE;
2936 }
463ee0b2
LW
2937 }
2938 }
79072805
LW
2939}
2940
c461cf8f
JH
2941/*
2942=for apidoc sv_utf8_upgrade
2943
78ea37eb 2944Converts the PV of an SV to its UTF-8-encoded form.
645c22ef 2945Forces the SV to string form if it is not already.
4411f3b6
NIS
2946Always sets the SvUTF8 flag to avoid future validity checks even
2947if all the bytes have hibit clear.
c461cf8f 2948
13a6c0e0
JH
2949This is not as a general purpose byte encoding to Unicode interface:
2950use the Encode extension for that.
2951
8d6d96c1
HS
2952=for apidoc sv_utf8_upgrade_flags
2953
78ea37eb 2954Converts the PV of an SV to its UTF-8-encoded form.
645c22ef 2955Forces the SV to string form if it is not already.
8d6d96c1
HS
2956Always sets the SvUTF8 flag to avoid future validity checks even
2957if all the bytes have hibit clear. If C<flags> has C<SV_GMAGIC> bit set,
2958will C<mg_get> on C<sv> if appropriate, else not. C<sv_utf8_upgrade> and
2959C<sv_utf8_upgrade_nomg> are implemented in terms of this function.
2960
13a6c0e0
JH
2961This is not as a general purpose byte encoding to Unicode interface:
2962use the Encode extension for that.
2963
8d6d96c1
HS
2964=cut
2965*/
2966
2967STRLEN
2968Perl_sv_utf8_upgrade_flags(pTHX_ register SV *sv, I32 flags)
2969{
97aff369 2970 dVAR;
808c356f
RGS
2971 if (sv == &PL_sv_undef)
2972 return 0;
e0e62c2a
NIS
2973 if (!SvPOK(sv)) {
2974 STRLEN len = 0;
d52b7888
NC
2975 if (SvREADONLY(sv) && (SvPOKp(sv) || SvIOKp(sv) || SvNOKp(sv))) {
2976 (void) sv_2pv_flags(sv,&len, flags);
2977 if (SvUTF8(sv))
2978 return len;
2979 } else {
2980 (void) SvPV_force(sv,len);
2981 }
e0e62c2a 2982 }
4411f3b6 2983
f5cee72b 2984 if (SvUTF8(sv)) {
5fec3b1d 2985 return SvCUR(sv);
f5cee72b 2986 }
5fec3b1d 2987
765f542d
NC
2988 if (SvIsCOW(sv)) {
2989 sv_force_normal_flags(sv, 0);
db42d148
NIS
2990 }
2991
88632417 2992 if (PL_encoding && !(flags & SV_UTF8_NO_ENCODING))
799ef3cb 2993 sv_recode_to_utf8(sv, PL_encoding);
9f4817db 2994 else { /* Assume Latin-1/EBCDIC */
c4e7c712
NC
2995 /* This function could be much more efficient if we
2996 * had a FLAG in SVs to signal if there are any hibit
2997 * chars in the PV. Given that there isn't such a flag
2998 * make the loop as fast as possible. */
00b6aa41 2999 const U8 * const s = (U8 *) SvPVX_const(sv);
c4420975 3000 const U8 * const e = (U8 *) SvEND(sv);
93524f2b 3001 const U8 *t = s;
c4e7c712
NC
3002
3003 while (t < e) {
53c1dcc0 3004 const U8 ch = *t++;
00b6aa41
AL
3005 /* Check for hi bit */
3006 if (!NATIVE_IS_INVARIANT(ch)) {
3007 STRLEN len = SvCUR(sv) + 1; /* Plus the \0 */
3008 U8 * const recoded = bytes_to_utf8((U8*)s, &len);
3009
3010 SvPV_free(sv); /* No longer using what was there before. */
3011 SvPV_set(sv, (char*)recoded);
3012 SvCUR_set(sv, len - 1);
3013 SvLEN_set(sv, len); /* No longer know the real size. */
c4e7c712 3014 break;
00b6aa41 3015 }
c4e7c712
NC
3016 }
3017 /* Mark as UTF-8 even if no hibit - saves scanning loop */
3018 SvUTF8_on(sv);
560a288e 3019 }
4411f3b6 3020 return SvCUR(sv);
560a288e
GS
3021}
3022
c461cf8f
JH
3023/*
3024=for apidoc sv_utf8_downgrade
3025
78ea37eb
ST
3026Attempts to convert the PV of an SV from characters to bytes.
3027If the PV contains a character beyond byte, this conversion will fail;
3028in this case, either returns false or, if C<fail_ok> is not
c461cf8f
JH
3029true, croaks.
3030
13a6c0e0
JH
3031This is not as a general purpose Unicode to byte encoding interface:
3032use the Encode extension for that.
3033
c461cf8f
JH
3034=cut
3035*/
3036
560a288e
GS
3037bool
3038Perl_sv_utf8_downgrade(pTHX_ register SV* sv, bool fail_ok)
3039{
97aff369 3040 dVAR;
78ea37eb 3041 if (SvPOKp(sv) && SvUTF8(sv)) {
fa301091 3042 if (SvCUR(sv)) {
03cfe0ae 3043 U8 *s;
652088fc 3044 STRLEN len;
fa301091 3045
765f542d
NC
3046 if (SvIsCOW(sv)) {
3047 sv_force_normal_flags(sv, 0);
3048 }
03cfe0ae
NIS
3049 s = (U8 *) SvPV(sv, len);
3050 if (!utf8_to_bytes(s, &len)) {
fa301091
JH
3051 if (fail_ok)
3052 return FALSE;
3053 else {
3054 if (PL_op)
3055 Perl_croak(aTHX_ "Wide character in %s",
53e06cf0 3056 OP_DESC(PL_op));
fa301091
JH
3057 else
3058 Perl_croak(aTHX_ "Wide character");
3059 }
4b3603a4 3060 }
b162af07 3061 SvCUR_set(sv, len);
67e989fb 3062 }
560a288e 3063 }
ffebcc3e 3064 SvUTF8_off(sv);
560a288e
GS
3065 return TRUE;
3066}
3067
c461cf8f
JH
3068/*
3069=for apidoc sv_utf8_encode
3070
78ea37eb
ST
3071Converts the PV of an SV to UTF-8, but then turns the C<SvUTF8>
3072flag off so that it looks like octets again.
c461cf8f
JH
3073
3074=cut
3075*/
3076
560a288e
GS
3077void
3078Perl_sv_utf8_encode(pTHX_ register SV *sv)
3079{
4c94c214
NC
3080 if (SvIsCOW(sv)) {
3081 sv_force_normal_flags(sv, 0);
3082 }
3083 if (SvREADONLY(sv)) {
3084 Perl_croak(aTHX_ PL_no_modify);
3085 }
a5f5288a 3086 (void) sv_utf8_upgrade(sv);
560a288e
GS
3087 SvUTF8_off(sv);
3088}
3089
4411f3b6
NIS
3090/*
3091=for apidoc sv_utf8_decode
3092
78ea37eb
ST
3093If the PV of the SV is an octet sequence in UTF-8
3094and contains a multiple-byte character, the C<SvUTF8> flag is turned on
3095so that it looks like a character. If the PV contains only single-byte
3096characters, the C<SvUTF8> flag stays being off.
3097Scans PV for validity and returns false if the PV is invalid UTF-8.
4411f3b6
NIS
3098
3099=cut
3100*/
3101
560a288e
GS
3102bool
3103Perl_sv_utf8_decode(pTHX_ register SV *sv)
3104{
78ea37eb 3105 if (SvPOKp(sv)) {
93524f2b
NC
3106 const U8 *c;
3107 const U8 *e;
9cbac4c7 3108
645c22ef
DM
3109 /* The octets may have got themselves encoded - get them back as
3110 * bytes
3111 */
3112 if (!sv_utf8_downgrade(sv, TRUE))
560a288e
GS
3113 return FALSE;
3114
3115 /* it is actually just a matter of turning the utf8 flag on, but
3116 * we want to make sure everything inside is valid utf8 first.
3117 */
93524f2b 3118 c = (const U8 *) SvPVX_const(sv);
63cd0674 3119 if (!is_utf8_string(c, SvCUR(sv)+1))
67e989fb 3120 return FALSE;
93524f2b 3121 e = (const U8 *) SvEND(sv);
511c2ff0 3122 while (c < e) {
b64e5050 3123 const U8 ch = *c++;
c4d5f83a 3124 if (!UTF8_IS_INVARIANT(ch)) {
67e989fb
JH
3125 SvUTF8_on(sv);
3126 break;
3127 }
560a288e 3128 }
560a288e
GS
3129 }
3130 return TRUE;
3131}
3132
954c1994
GS
3133/*
3134=for apidoc sv_setsv
3135
645c22ef
DM
3136Copies the contents of the source SV C<ssv> into the destination SV
3137C<dsv>. The source SV may be destroyed if it is mortal, so don't use this
3138function if the source SV needs to be reused. Does not handle 'set' magic.
3139Loosely speaking, it performs a copy-by-value, obliterating any previous
3140content of the destination.
3141
3142You probably want to use one of the assortment of wrappers, such as
3143C<SvSetSV>, C<SvSetSV_nosteal>, C<SvSetMagicSV> and
3144C<SvSetMagicSV_nosteal>.
3145
8d6d96c1
HS
3146=for apidoc sv_setsv_flags
3147
645c22ef
DM
3148Copies the contents of the source SV C<ssv> into the destination SV
3149C<dsv>. The source SV may be destroyed if it is mortal, so don't use this
3150function if the source SV needs to be reused. Does not handle 'set' magic.
3151Loosely speaking, it performs a copy-by-value, obliterating any previous
3152content of the destination.
3153If the C<flags> parameter has the C<SV_GMAGIC> bit set, will C<mg_get> on
5fcdf167
NC
3154C<ssv> if appropriate, else not. If the C<flags> parameter has the
3155C<NOSTEAL> bit set then the buffers of temps will not be stolen. <sv_setsv>
3156and C<sv_setsv_nomg> are implemented in terms of this function.
645c22ef
DM
3157
3158You probably want to use one of the assortment of wrappers, such as
3159C<SvSetSV>, C<SvSetSV_nosteal>, C<SvSetMagicSV> and
3160C<SvSetMagicSV_nosteal>.
3161
3162This is the primary function for copying scalars, and most other
3163copy-ish functions and macros use this underneath.
8d6d96c1
HS
3164
3165=cut
3166*/
3167
5d0301b7 3168static void
2eb42952 3169S_glob_assign_glob(pTHX_ SV *dstr, SV *sstr, const int dtype)
5d0301b7
NC
3170{
3171 if (dtype != SVt_PVGV) {
3172 const char * const name = GvNAME(sstr);
3173 const STRLEN len = GvNAMELEN(sstr);
3174 /* don't upgrade SVt_PVLV: it can hold a glob */
f7877b28
NC
3175 if (dtype != SVt_PVLV) {
3176 if (dtype >= SVt_PV) {
3177 SvPV_free(dstr);
3178 SvPV_set(dstr, 0);
3179 SvLEN_set(dstr, 0);
3180 SvCUR_set(dstr, 0);
3181 }
5d0301b7 3182 sv_upgrade(dstr, SVt_PVGV);
dedf8e73 3183 (void)SvOK_off(dstr);
2e5b91de
NC
3184 /* FIXME - why are we doing this, then turning it off and on again
3185 below? */
3186 isGV_with_GP_on(dstr);
f7877b28 3187 }
5d0301b7
NC
3188 GvSTASH(dstr) = GvSTASH(sstr);
3189 if (GvSTASH(dstr))
3190 Perl_sv_add_backref(aTHX_ (SV*)GvSTASH(dstr), dstr);
ae8cc45f 3191 gv_name_set((GV *)dstr, name, len, GV_ADD);
5d0301b7
NC
3192 SvFAKE_on(dstr); /* can coerce to non-glob */
3193 }
3194
3195#ifdef GV_UNIQUE_CHECK
3196 if (GvUNIQUE((GV*)dstr)) {
3197 Perl_croak(aTHX_ PL_no_modify);
3198 }
3199#endif
3200
f7877b28 3201 gp_free((GV*)dstr);
2e5b91de 3202 isGV_with_GP_off(dstr);
5d0301b7 3203 (void)SvOK_off(dstr);
2e5b91de 3204 isGV_with_GP_on(dstr);
dedf8e73 3205 GvINTRO_off(dstr); /* one-shot flag */
5d0301b7
NC
3206 GvGP(dstr) = gp_ref(GvGP(sstr));
3207 if (SvTAINTED(sstr))
3208 SvTAINT(dstr);
3209 if (GvIMPORTED(dstr) != GVf_IMPORTED
3210 && CopSTASH_ne(PL_curcop, GvSTASH(dstr)))
3211 {
3212 GvIMPORTED_on(dstr);
3213 }
3214 GvMULTI_on(dstr);
3215 return;
3216}
3217
b8473700 3218static void
2eb42952 3219S_glob_assign_ref(pTHX_ SV *dstr, SV *sstr) {
b8473700
NC
3220 SV * const sref = SvREFCNT_inc(SvRV(sstr));
3221 SV *dref = NULL;
3222 const int intro = GvINTRO(dstr);
2440974c 3223 SV **location;
3386d083 3224 U8 import_flag = 0;
27242d61
NC
3225 const U32 stype = SvTYPE(sref);
3226
b8473700
NC
3227
3228#ifdef GV_UNIQUE_CHECK
3229 if (GvUNIQUE((GV*)dstr)) {
3230 Perl_croak(aTHX_ PL_no_modify);
3231 }
3232#endif
3233
3234 if (intro) {
3235 GvINTRO_off(dstr); /* one-shot flag */
3236 GvLINE(dstr) = CopLINE(PL_curcop);
3237 GvEGV(dstr) = (GV*)dstr;
3238 }
3239 GvMULTI_on(dstr);
27242d61 3240 switch (stype) {
b8473700 3241 case SVt_PVCV:
27242d61
NC
3242 location = (SV **) &GvCV(dstr);
3243 import_flag = GVf_IMPORTED_CV;
3244 goto common;
3245 case SVt_PVHV:
3246 location = (SV **) &GvHV(dstr);
3247 import_flag = GVf_IMPORTED_HV;
3248 goto common;
3249 case SVt_PVAV:
3250 location = (SV **) &GvAV(dstr);
3251 import_flag = GVf_IMPORTED_AV;
3252 goto common;
3253 case SVt_PVIO:
3254 location = (SV **) &GvIOp(dstr);
3255 goto common;
3256 case SVt_PVFM:
3257 location = (SV **) &GvFORM(dstr);
3258 default:
3259 location = &GvSV(dstr);
3260 import_flag = GVf_IMPORTED_SV;
3261 common:
b8473700 3262 if (intro) {
27242d61
NC
3263 if (stype == SVt_PVCV) {
3264 if (GvCVGEN(dstr) && GvCV(dstr) != (CV*)sref) {
3265 SvREFCNT_dec(GvCV(dstr));
3266 GvCV(dstr) = NULL;
3267 GvCVGEN(dstr) = 0; /* Switch off cacheness. */
3268 PL_sub_generation++;
3269 }
b8473700 3270 }
27242d61 3271 SAVEGENERICSV(*location);
b8473700
NC
3272 }
3273 else
27242d61
NC
3274 dref = *location;
3275 if (stype == SVt_PVCV && *location != sref) {
3276 CV* const cv = (CV*)*location;
b8473700
NC
3277 if (cv) {
3278 if (!GvCVGEN((GV*)dstr) &&
3279 (CvROOT(cv) || CvXSUB(cv)))
3280 {
3281 /* Redefining a sub - warning is mandatory if
3282 it was a const and its value changed. */
3283 if (CvCONST(cv) && CvCONST((CV*)sref)
3284 && cv_const_sv(cv) == cv_const_sv((CV*)sref)) {
6f207bd3 3285 NOOP;
b8473700
NC
3286 /* They are 2 constant subroutines generated from
3287 the same constant. This probably means that
3288 they are really the "same" proxy subroutine
3289 instantiated in 2 places. Most likely this is
3290 when a constant is exported twice. Don't warn.
3291 */
3292 }
3293 else if (ckWARN(WARN_REDEFINE)
3294 || (CvCONST(cv)
3295 && (!CvCONST((CV*)sref)
3296 || sv_cmp(cv_const_sv(cv),
3297 cv_const_sv((CV*)sref))))) {
3298 Perl_warner(aTHX_ packWARN(WARN_REDEFINE),
10edeb5d
JH
3299 (const char *)
3300 (CvCONST(cv)
3301 ? "Constant subroutine %s::%s redefined"
3302 : "Subroutine %s::%s redefined"),
b8473700
NC
3303 HvNAME_get(GvSTASH((GV*)dstr)),
3304 GvENAME((GV*)dstr));
3305 }
3306 }
3307 if (!intro)
cbf82dd0
NC
3308 cv_ckproto_len(cv, (GV*)dstr,
3309 SvPOK(sref) ? SvPVX_const(sref) : NULL,
3310 SvPOK(sref) ? SvCUR(sref) : 0);
b8473700 3311 }
b8473700
NC
3312 GvCVGEN(dstr) = 0; /* Switch off cacheness. */
3313 GvASSUMECV_on(dstr);
3314 PL_sub_generation++;
3315 }
2440974c 3316 *location = sref;
3386d083
NC
3317 if (import_flag && !(GvFLAGS(dstr) & import_flag)
3318 && CopSTASH_ne(PL_curcop, GvSTASH(dstr))) {
3319 GvFLAGS(dstr) |= import_flag;
b8473700
NC
3320 }
3321 break;
3322 }
b37c2d43 3323 SvREFCNT_dec(dref);
b8473700
NC
3324 if (SvTAINTED(sstr))
3325 SvTAINT(dstr);
3326 return;
3327}
3328
8d6d96c1
HS
3329void
3330Perl_sv_setsv_flags(pTHX_ SV *dstr, register SV *sstr, I32 flags)
3331{
97aff369 3332 dVAR;
8990e307
LW
3333 register U32 sflags;
3334 register int dtype;
42d0e0b7 3335 register svtype stype;
463ee0b2 3336
79072805
LW
3337 if (sstr == dstr)
3338 return;
29f4f0ab
NC
3339
3340 if (SvIS_FREED(dstr)) {
3341 Perl_croak(aTHX_ "panic: attempt to copy value %" SVf
be2597df 3342 " to a freed scalar %p", SVfARG(sstr), (void *)dstr);
29f4f0ab 3343 }
765f542d 3344 SV_CHECK_THINKFIRST_COW_DROP(dstr);
79072805 3345 if (!sstr)
3280af22 3346 sstr = &PL_sv_undef;
29f4f0ab 3347 if (SvIS_FREED(sstr)) {
6c9570dc
MHM
3348 Perl_croak(aTHX_ "panic: attempt to copy freed scalar %p to %p",
3349 (void*)sstr, (void*)dstr);
29f4f0ab 3350 }
8990e307
LW
3351 stype = SvTYPE(sstr);
3352 dtype = SvTYPE(dstr);
79072805 3353
a0d0e21e 3354 SvAMAGIC_off(dstr);
7a5fa8a2 3355 if ( SvVOK(dstr) )
ece467f9
JP
3356 {
3357 /* need to nuke the magic */
3358 mg_free(dstr);
3359 SvRMAGICAL_off(dstr);
3360 }
9e7bc3e8 3361
463ee0b2 3362 /* There's a lot of redundancy below but we're going for speed here */
79072805 3363
8990e307 3364 switch (stype) {
79072805 3365 case SVt_NULL:
aece5585 3366 undef_sstr:
20408e3c
GS
3367 if (dtype != SVt_PVGV) {
3368 (void)SvOK_off(dstr);
3369 return;
3370 }
3371 break;
463ee0b2 3372 case SVt_IV:
aece5585
GA
3373 if (SvIOK(sstr)) {
3374 switch (dtype) {
3375 case SVt_NULL:
8990e307 3376 sv_upgrade(dstr, SVt_IV);
aece5585
GA
3377 break;
3378 case SVt_NV:
aece5585
GA
3379 case SVt_RV:
3380 case SVt_PV:
a0d0e21e 3381 sv_upgrade(dstr, SVt_PVIV);
aece5585 3382 break;
010be86b
NC
3383 case SVt_PVGV:
3384 goto end_of_first_switch;
aece5585
GA
3385 }
3386 (void)SvIOK_only(dstr);
45977657 3387 SvIV_set(dstr, SvIVX(sstr));
25da4f38
IZ
3388 if (SvIsUV(sstr))
3389 SvIsUV_on(dstr);
37c25af0
NC
3390 /* SvTAINTED can only be true if the SV has taint magic, which in
3391 turn means that the SV type is PVMG (or greater). This is the
3392 case statement for SVt_IV, so this cannot be true (whatever gcov
3393 may say). */
3394 assert(!SvTAINTED(sstr));
aece5585 3395 return;
8990e307 3396 }
aece5585
GA
3397 goto undef_sstr;
3398
463ee0b2 3399 case SVt_NV:
aece5585
GA
3400 if (SvNOK(sstr)) {
3401 switch (dtype) {
3402 case SVt_NULL:
3403 case SVt_IV:
8990e307 3404 sv_upgrade(dstr, SVt_NV);
aece5585
GA
3405 break;
3406 case SVt_RV:
3407 case SVt_PV:
3408 case SVt_PVIV:
a0d0e21e 3409 sv_upgrade(dstr, SVt_PVNV);
aece5585 3410 break;
010be86b
NC
3411 case SVt_PVGV:
3412 goto end_of_first_switch;
aece5585 3413 }
9d6ce603 3414 SvNV_set(dstr, SvNVX(sstr));
aece5585 3415 (void)SvNOK_only(dstr);
37c25af0
NC
3416 /* SvTAINTED can only be true if the SV has taint magic, which in
3417 turn means that the SV type is PVMG (or greater). This is the
3418 case statement for SVt_NV, so this cannot be true (whatever gcov
3419 may say). */
3420 assert(!SvTAINTED(sstr));
aece5585 3421 return;
8990e307 3422 }
aece5585
GA
3423 goto undef_sstr;
3424
ed6116ce 3425 case SVt_RV:
8990e307 3426 if (dtype < SVt_RV)
ed6116ce 3427 sv_upgrade(dstr, SVt_RV);
ed6116ce 3428 break;
fc36a67e 3429 case SVt_PVFM:
f8c7b90f 3430#ifdef PERL_OLD_COPY_ON_WRITE
d89fc664
NC
3431 if ((SvFLAGS(sstr) & CAN_COW_MASK) == CAN_COW_FLAGS) {
3432 if (dtype < SVt_PVIV)
3433 sv_upgrade(dstr, SVt_PVIV);
3434 break;
3435 }
3436 /* Fall through */
3437#endif
3438 case SVt_PV:
8990e307 3439 if (dtype < SVt_PV)
463ee0b2 3440 sv_upgrade(dstr, SVt_PV);
463ee0b2
LW
3441 break;
3442 case SVt_PVIV:
8990e307 3443 if (dtype < SVt_PVIV)
463ee0b2 3444 sv_upgrade(dstr, SVt_PVIV);
463ee0b2
LW
3445 break;
3446 case SVt_PVNV:
8990e307 3447 if (dtype < SVt_PVNV)
463ee0b2 3448 sv_upgrade(dstr, SVt_PVNV);
463ee0b2 3449 break;
489f7bfe 3450 default:
a3b680e6
AL
3451 {
3452 const char * const type = sv_reftype(sstr,0);
533c011a 3453 if (PL_op)
a3b680e6 3454 Perl_croak(aTHX_ "Bizarre copy of %s in %s", type, OP_NAME(PL_op));
4633a7c4 3455 else
a3b680e6
AL
3456 Perl_croak(aTHX_ "Bizarre copy of %s", type);
3457 }
4633a7c4
LW
3458 break;
3459
cecf5685 3460 /* case SVt_BIND: */
79072805 3461 case SVt_PVGV:
cecf5685 3462 if (isGV_with_GP(sstr) && dtype <= SVt_PVGV) {
d4c19fe8 3463 glob_assign_glob(dstr, sstr, dtype);
b8c701c1 3464 return;
79072805 3465 }
cecf5685 3466 /* SvVALID means that this PVGV is playing at being an FBM. */
5f66b61c 3467 /*FALLTHROUGH*/
79072805 3468
489f7bfe
NC
3469 case SVt_PVMG:
3470 case SVt_PVLV:
8d6d96c1 3471 if (SvGMAGICAL(sstr) && (flags & SV_GMAGIC)) {
973f89ab 3472 mg_get(sstr);
1d9c78c6 3473 if (SvTYPE(sstr) != stype) {
973f89ab 3474 stype = SvTYPE(sstr);
cecf5685 3475 if (isGV_with_GP(sstr) && stype == SVt_PVGV && dtype <= SVt_PVGV) {
d4c19fe8 3476 glob_assign_glob(dstr, sstr, dtype);
b8c701c1
NC
3477 return;
3478 }
973f89ab
CS
3479 }
3480 }
ded42b9f 3481 if (stype == SVt_PVLV)
862a34c6 3482 SvUPGRADE(dstr, SVt_PVNV);
ded42b9f 3483 else
42d0e0b7 3484 SvUPGRADE(dstr, (svtype)stype);
79072805 3485 }
010be86b 3486 end_of_first_switch:
79072805 3487
ff920335
NC
3488 /* dstr may have been upgraded. */
3489 dtype = SvTYPE(dstr);
8990e307
LW
3490 sflags = SvFLAGS(sstr);
3491
ba2fdce6 3492 if (dtype == SVt_PVCV || dtype == SVt_PVFM) {
85324b4d
NC
3493 /* Assigning to a subroutine sets the prototype. */
3494 if (SvOK(sstr)) {
3495 STRLEN len;
3496 const char *const ptr = SvPV_const(sstr, len);
3497
3498 SvGROW(dstr, len + 1);
3499 Copy(ptr, SvPVX(dstr), len + 1, char);
3500 SvCUR_set(dstr, len);
fcddd32e 3501 SvPOK_only(dstr);
ba2fdce6 3502 SvFLAGS(dstr) |= sflags & SVf_UTF8;
85324b4d
NC
3503 } else {
3504 SvOK_off(dstr);
3505 }
ba2fdce6
NC
3506 } else if (dtype == SVt_PVAV || dtype == SVt_PVHV) {
3507 const char * const type = sv_reftype(dstr,0);
3508 if (PL_op)
3509 Perl_croak(aTHX_ "Cannot copy to %s in %s", type, OP_NAME(PL_op));
3510 else
3511 Perl_croak(aTHX_ "Cannot copy to %s", type);
85324b4d 3512 } else if (sflags & SVf_ROK) {
cecf5685
NC
3513 if (isGV_with_GP(dstr) && dtype == SVt_PVGV
3514 && SvTYPE(SvRV(sstr)) == SVt_PVGV) {
acaa9288
NC
3515 sstr = SvRV(sstr);
3516 if (sstr == dstr) {
3517 if (GvIMPORTED(dstr) != GVf_IMPORTED
3518 && CopSTASH_ne(PL_curcop, GvSTASH(dstr)))
3519 {
3520 GvIMPORTED_on(dstr);
3521 }
3522 GvMULTI_on(dstr);
3523 return;
3524 }
d4c19fe8 3525 glob_assign_glob(dstr, sstr, dtype);
acaa9288
NC
3526 return;
3527 }
3528
8990e307 3529 if (dtype >= SVt_PV) {
b8c701c1 3530 if (dtype == SVt_PVGV) {
d4c19fe8 3531 glob_assign_ref(dstr, sstr);
b8c701c1
NC
3532 return;
3533 }
3f7c398e 3534 if (SvPVX_const(dstr)) {
8bd4d4c5 3535 SvPV_free(dstr);
b162af07
SP
3536 SvLEN_set(dstr, 0);
3537 SvCUR_set(dstr, 0);
a0d0e21e 3538 }
8990e307 3539 }
a0d0e21e 3540 (void)SvOK_off(dstr);
b162af07 3541 SvRV_set(dstr, SvREFCNT_inc(SvRV(sstr)));
96d4b0ee 3542 SvFLAGS(dstr) |= sflags & SVf_ROK;
dfd48732
NC
3543 assert(!(sflags & SVp_NOK));
3544 assert(!(sflags & SVp_IOK));
3545 assert(!(sflags & SVf_NOK));
3546 assert(!(sflags & SVf_IOK));
ed6116ce 3547 }
cecf5685 3548 else if (dtype == SVt_PVGV && isGV_with_GP(dstr)) {
c0c44674
NC
3549 if (!(sflags & SVf_OK)) {
3550 if (ckWARN(WARN_MISC))
3551 Perl_warner(aTHX_ packWARN(WARN_MISC),
3552 "Undefined value assigned to typeglob");
3553 }
3554 else {
3555 GV *gv = gv_fetchsv(sstr, GV_ADD, SVt_PVGV);
3556 if (dstr != (SV*)gv) {
3557 if (GvGP(dstr))
3558 gp_free((GV*)dstr);
3559 GvGP(dstr) = gp_ref(GvGP(gv));
3560 }
3561 }
3562 }
8990e307 3563 else if (sflags & SVp_POK) {
765f542d 3564 bool isSwipe = 0;
79072805
LW
3565
3566 /*
3567 * Check to see if we can just swipe the string. If so, it's a
3568 * possible small lose on short strings, but a big win on long ones.
3f7c398e
SP
3569 * It might even be a win on short strings if SvPVX_const(dstr)
3570 * has to be allocated and SvPVX_const(sstr) has to be freed.
34482cd6
NC
3571 * Likewise if we can set up COW rather than doing an actual copy, we
3572 * drop to the else clause, as the swipe code and the COW setup code
3573 * have much in common.
79072805
LW
3574 */
3575
120fac95
NC
3576 /* Whichever path we take through the next code, we want this true,
3577 and doing it now facilitates the COW check. */
3578 (void)SvPOK_only(dstr);
3579
765f542d 3580 if (
34482cd6
NC
3581 /* If we're already COW then this clause is not true, and if COW
3582 is allowed then we drop down to the else and make dest COW
3583 with us. If caller hasn't said that we're allowed to COW
3584 shared hash keys then we don't do the COW setup, even if the
3585 source scalar is a shared hash key scalar. */
3586 (((flags & SV_COW_SHARED_HASH_KEYS)
3587 ? (sflags & (SVf_FAKE|SVf_READONLY)) != (SVf_FAKE|SVf_READONLY)
3588 : 1 /* If making a COW copy is forbidden then the behaviour we
3589 desire is as if the source SV isn't actually already
3590 COW, even if it is. So we act as if the source flags
3591 are not COW, rather than actually testing them. */
3592 )
f8c7b90f 3593#ifndef PERL_OLD_COPY_ON_WRITE
34482cd6
NC
3594 /* The change that added SV_COW_SHARED_HASH_KEYS makes the logic
3595 when PERL_OLD_COPY_ON_WRITE is defined a little wrong.
3596 Conceptually PERL_OLD_COPY_ON_WRITE being defined should
3597 override SV_COW_SHARED_HASH_KEYS, because it means "always COW"
3598 but in turn, it's somewhat dead code, never expected to go
3599 live, but more kept as a placeholder on how to do it better
3600 in a newer implementation. */
3601 /* If we are COW and dstr is a suitable target then we drop down
3602 into the else and make dest a COW of us. */
b8f9541a
NC
3603 || (SvFLAGS(dstr) & CAN_COW_MASK) != CAN_COW_FLAGS
3604#endif
3605 )
765f542d 3606 &&
765f542d
NC
3607 !(isSwipe =
3608 (sflags & SVs_TEMP) && /* slated for free anyway? */
3609 !(sflags & SVf_OOK) && /* and not involved in OOK hack? */
5fcdf167
NC
3610 (!(flags & SV_NOSTEAL)) &&
3611 /* and we're allowed to steal temps */
765f542d
NC
3612 SvREFCNT(sstr) == 1 && /* and no other references to it? */
3613 SvLEN(sstr) && /* and really is a string */
645c22ef 3614 /* and won't be needed again, potentially */
765f542d 3615 !(PL_op && PL_op->op_type == OP_AASSIGN))
f8c7b90f 3616#ifdef PERL_OLD_COPY_ON_WRITE
765f542d 3617 && !((sflags & CAN_COW_MASK) == CAN_COW_FLAGS
120fac95 3618 && (SvFLAGS(dstr) & CAN_COW_MASK) == CAN_COW_FLAGS
765f542d
NC
3619 && SvTYPE(sstr) >= SVt_PVIV)
3620#endif
3621 ) {
3622 /* Failed the swipe test, and it's not a shared hash key either.
3623 Have to copy the string. */
3624 STRLEN len = SvCUR(sstr);
3625 SvGROW(dstr, len + 1); /* inlined from sv_setpvn */
3f7c398e 3626 Move(SvPVX_const(sstr),SvPVX(dstr),len,char);
765f542d
NC
3627 SvCUR_set(dstr, len);
3628 *SvEND(dstr) = '\0';
765f542d 3629 } else {
f8c7b90f 3630 /* If PERL_OLD_COPY_ON_WRITE is not defined, then isSwipe will always
765f542d 3631 be true in here. */
765f542d
NC
3632 /* Either it's a shared hash key, or it's suitable for
3633 copy-on-write or we can swipe the string. */
46187eeb 3634 if (DEBUG_C_TEST) {
ed252734 3635 PerlIO_printf(Perl_debug_log, "Copy on write: sstr --> dstr\n");
e419cbc5
NC
3636 sv_dump(sstr);
3637 sv_dump(dstr);
46187eeb 3638 }
f8c7b90f 3639#ifdef PERL_OLD_COPY_ON_WRITE
765f542d
NC
3640 if (!isSwipe) {
3641 /* I believe I should acquire a global SV mutex if
3642 it's a COW sv (not a shared hash key) to stop
3643 it going un copy-on-write.
3644 If the source SV has gone un copy on write between up there
3645 and down here, then (assert() that) it is of the correct
3646 form to make it copy on write again */
3647 if ((sflags & (SVf_FAKE | SVf_READONLY))
3648 != (SVf_FAKE | SVf_READONLY)) {
3649 SvREADONLY_on(sstr);
3650 SvFAKE_on(sstr);
3651 /* Make the source SV into a loop of 1.
3652 (about to become 2) */
a29f6d03 3653 SV_COW_NEXT_SV_SET(sstr, sstr);
765f542d
NC
3654 }
3655 }
3656#endif
3657 /* Initial code is common. */
94010e71
NC
3658 if (SvPVX_const(dstr)) { /* we know that dtype >= SVt_PV */
3659 SvPV_free(dstr);
79072805 3660 }
765f542d 3661
765f542d
NC
3662 if (!isSwipe) {
3663 /* making another shared SV. */
3664 STRLEN cur = SvCUR(sstr);
3665 STRLEN len = SvLEN(sstr);
f8c7b90f 3666#ifdef PERL_OLD_COPY_ON_WRITE
765f542d 3667 if (len) {
b8f9541a 3668 assert (SvTYPE(dstr) >= SVt_PVIV);
765f542d
NC
3669 /* SvIsCOW_normal */
3670 /* splice us in between source and next-after-source. */
a29f6d03
NC
3671 SV_COW_NEXT_SV_SET(dstr, SV_COW_NEXT_SV(sstr));
3672 SV_COW_NEXT_SV_SET(sstr, dstr);
940132f3 3673 SvPV_set(dstr, SvPVX_mutable(sstr));
a604c751
NC
3674 } else
3675#endif
3676 {
765f542d 3677 /* SvIsCOW_shared_hash */
46187eeb
NC
3678 DEBUG_C(PerlIO_printf(Perl_debug_log,
3679 "Copy on write: Sharing hash\n"));
b8f9541a 3680
bdd68bc3 3681 assert (SvTYPE(dstr) >= SVt_PV);
765f542d 3682 SvPV_set(dstr,
d1db91c6 3683 HEK_KEY(share_hek_hek(SvSHARED_HEK_FROM_PV(SvPVX_const(sstr)))));
bdd68bc3 3684 }
87a1ef3d
SP
3685 SvLEN_set(dstr, len);
3686 SvCUR_set(dstr, cur);
765f542d
NC
3687 SvREADONLY_on(dstr);
3688 SvFAKE_on(dstr);
3689 /* Relesase a global SV mutex. */
3690 }
3691 else
765f542d 3692 { /* Passes the swipe test. */
78d1e721 3693 SvPV_set(dstr, SvPVX_mutable(sstr));
765f542d
NC
3694 SvLEN_set(dstr, SvLEN(sstr));
3695 SvCUR_set(dstr, SvCUR(sstr));
3696
3697 SvTEMP_off(dstr);
3698 (void)SvOK_off(sstr); /* NOTE: nukes most SvFLAGS on sstr */
6136c704 3699 SvPV_set(sst