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Test arrays containing references, and references to shared arrays.
[perl5.git] / universal.c
CommitLineData
d6376244
JH
1/* universal.c
2 *
3 * Copyright (c) 1997-2002, Larry Wall
4 *
5 * You may distribute under the terms of either the GNU General Public
6 * License or the Artistic License, as specified in the README file.
7 *
8 */
9
d31a8517
AT
10/*
11 * "The roots of those mountains must be roots indeed; there must be
12 * great secrets buried there which have not been discovered since the
13 * beginning." --Gandalf, relating Gollum's story
14 */
15
6d4a7be2 16#include "EXTERN.h"
864dbfa3 17#define PERL_IN_UNIVERSAL_C
6d4a7be2 18#include "perl.h"
6d4a7be2
PP
19
20/*
21 * Contributed by Graham Barr <Graham.Barr@tiuk.ti.com>
22 * The main guts of traverse_isa was actually copied from gv_fetchmeth
23 */
24
76e3520e 25STATIC SV *
301daebc
MS
26S_isa_lookup(pTHX_ HV *stash, const char *name, HV* name_stash,
27 int len, int level)
6d4a7be2
PP
28{
29 AV* av;
30 GV* gv;
31 GV** gvp;
32 HV* hv = Nullhv;
46e4b22b 33 SV* subgen = Nullsv;
6d4a7be2 34
301daebc
MS
35 /* A stash/class can go by many names (ie. User == main::User), so
36 we compare the stash itself just in case */
37 if (name_stash && (stash == name_stash))
38 return &PL_sv_yes;
6d4a7be2 39
46e4b22b 40 if (strEQ(HvNAME(stash), name))
3280af22 41 return &PL_sv_yes;
6d4a7be2
PP
42
43 if (level > 100)
46e4b22b
GS
44 Perl_croak(aTHX_ "Recursive inheritance detected in package '%s'",
45 HvNAME(stash));
6d4a7be2
PP
46
47 gvp = (GV**)hv_fetch(stash, "::ISA::CACHE::", 14, FALSE);
48
46e4b22b
GS
49 if (gvp && (gv = *gvp) != (GV*)&PL_sv_undef && (subgen = GvSV(gv))
50 && (hv = GvHV(gv)))
51 {
52 if (SvIV(subgen) == PL_sub_generation) {
53 SV* sv;
54 SV** svp = (SV**)hv_fetch(hv, name, len, FALSE);
55 if (svp && (sv = *svp) != (SV*)&PL_sv_undef) {
56 DEBUG_o( Perl_deb(aTHX_ "Using cached ISA %s for package %s\n",
57 name, HvNAME(stash)) );
58 return sv;
59 }
60 }
61 else {
62 DEBUG_o( Perl_deb(aTHX_ "ISA Cache in package %s is stale\n",
63 HvNAME(stash)) );
64 hv_clear(hv);
65 sv_setiv(subgen, PL_sub_generation);
66 }
6d4a7be2
PP
67 }
68
69 gvp = (GV**)hv_fetch(stash,"ISA",3,FALSE);
46e4b22b 70
3280af22 71 if (gvp && (gv = *gvp) != (GV*)&PL_sv_undef && (av = GvAV(gv))) {
46e4b22b 72 if (!hv || !subgen) {
6d4a7be2
PP
73 gvp = (GV**)hv_fetch(stash, "::ISA::CACHE::", 14, TRUE);
74
75 gv = *gvp;
76
77 if (SvTYPE(gv) != SVt_PVGV)
78 gv_init(gv, stash, "::ISA::CACHE::", 14, TRUE);
79
46e4b22b
GS
80 if (!hv)
81 hv = GvHVn(gv);
82 if (!subgen) {
83 subgen = newSViv(PL_sub_generation);
84 GvSV(gv) = subgen;
85 }
6d4a7be2 86 }
46e4b22b 87 if (hv) {
6d4a7be2 88 SV** svp = AvARRAY(av);
93965878
NIS
89 /* NOTE: No support for tied ISA */
90 I32 items = AvFILLp(av) + 1;
6d4a7be2
PP
91 while (items--) {
92 SV* sv = *svp++;
93 HV* basestash = gv_stashsv(sv, FALSE);
94 if (!basestash) {
599cee73 95 if (ckWARN(WARN_MISC))
9014280d 96 Perl_warner(aTHX_ packWARN(WARN_SYNTAX),
599cee73 97 "Can't locate package %s for @%s::ISA",
6d4a7be2
PP
98 SvPVX(sv), HvNAME(stash));
99 continue;
100 }
301daebc
MS
101 if (&PL_sv_yes == isa_lookup(basestash, name, name_stash,
102 len, level + 1)) {
3280af22
NIS
103 (void)hv_store(hv,name,len,&PL_sv_yes,0);
104 return &PL_sv_yes;
6d4a7be2
PP
105 }
106 }
3280af22 107 (void)hv_store(hv,name,len,&PL_sv_no,0);
6d4a7be2
PP
108 }
109 }
110
e09f3e01 111 return boolSV(strEQ(name, "UNIVERSAL"));
6d4a7be2
PP
112}
113
954c1994 114/*
ccfc67b7
JH
115=head1 SV Manipulation Functions
116
954c1994
GS
117=for apidoc sv_derived_from
118
119Returns a boolean indicating whether the SV is derived from the specified
120class. This is the function that implements C<UNIVERSAL::isa>. It works
121for class names as well as for objects.
122
123=cut
124*/
125
55497cff 126bool
864dbfa3 127Perl_sv_derived_from(pTHX_ SV *sv, const char *name)
55497cff 128{
55497cff
PP
129 char *type;
130 HV *stash;
301daebc 131 HV *name_stash;
46e4b22b 132
55497cff
PP
133 stash = Nullhv;
134 type = Nullch;
46e4b22b 135
55497cff
PP
136 if (SvGMAGICAL(sv))
137 mg_get(sv) ;
138
139 if (SvROK(sv)) {
140 sv = SvRV(sv);
141 type = sv_reftype(sv,0);
46e4b22b 142 if (SvOBJECT(sv))
55497cff
PP
143 stash = SvSTASH(sv);
144 }
145 else {
146 stash = gv_stashsv(sv, FALSE);
147 }
46e4b22b 148
301daebc
MS
149 name_stash = gv_stashpv(name, FALSE);
150
55497cff 151 return (type && strEQ(type,name)) ||
301daebc
MS
152 (stash && isa_lookup(stash, name, name_stash, strlen(name), 0)
153 == &PL_sv_yes)
55497cff
PP
154 ? TRUE
155 : FALSE ;
55497cff
PP
156}
157
1b026014
NIS
158#include "XSUB.h"
159
acfe0abc
GS
160void XS_UNIVERSAL_isa(pTHX_ CV *cv);
161void XS_UNIVERSAL_can(pTHX_ CV *cv);
162void XS_UNIVERSAL_VERSION(pTHX_ CV *cv);
1b026014
NIS
163XS(XS_utf8_valid);
164XS(XS_utf8_encode);
165XS(XS_utf8_decode);
166XS(XS_utf8_upgrade);
167XS(XS_utf8_downgrade);
168XS(XS_utf8_unicode_to_native);
169XS(XS_utf8_native_to_unicode);
29569577
JH
170XS(XS_Internals_SvREADONLY);
171XS(XS_Internals_SvREFCNT);
dfd4ef2f 172XS(XS_Internals_hv_clear_placeholders);
0cb96387
GS
173
174void
175Perl_boot_core_UNIVERSAL(pTHX)
176{
177 char *file = __FILE__;
178
179 newXS("UNIVERSAL::isa", XS_UNIVERSAL_isa, file);
180 newXS("UNIVERSAL::can", XS_UNIVERSAL_can, file);
181 newXS("UNIVERSAL::VERSION", XS_UNIVERSAL_VERSION, file);
1b026014
NIS
182 newXS("utf8::valid", XS_utf8_valid, file);
183 newXS("utf8::encode", XS_utf8_encode, file);
184 newXS("utf8::decode", XS_utf8_decode, file);
185 newXS("utf8::upgrade", XS_utf8_upgrade, file);
186 newXS("utf8::downgrade", XS_utf8_downgrade, file);
187 newXS("utf8::native_to_unicode", XS_utf8_native_to_unicode, file);
188 newXS("utf8::unicode_to_native", XS_utf8_unicode_to_native, file);
29569577
JH
189 newXSproto("Internals::SvREADONLY",XS_Internals_SvREADONLY, file, "\\[$%@];$");
190 newXSproto("Internals::SvREFCNT",XS_Internals_SvREFCNT, file, "\\[$%@];$");
dfd4ef2f
NC
191 newXSproto("Internals::hv_clear_placeholders",
192 XS_Internals_hv_clear_placeholders, file, "\\%");
0cb96387
GS
193}
194
55497cff 195
6d4a7be2
PP
196XS(XS_UNIVERSAL_isa)
197{
198 dXSARGS;
55497cff
PP
199 SV *sv;
200 char *name;
2d8e6c8d 201 STRLEN n_a;
6d4a7be2
PP
202
203 if (items != 2)
cea2e8a9 204 Perl_croak(aTHX_ "Usage: UNIVERSAL::isa(reference, kind)");
6d4a7be2
PP
205
206 sv = ST(0);
f8f70380 207
d3f7f2b2
GS
208 if (SvGMAGICAL(sv))
209 mg_get(sv);
210
aca069ec 211 if (!SvOK(sv) || !(SvROK(sv) || (SvPOK(sv) && SvCUR(sv))))
f8f70380
GS
212 XSRETURN_UNDEF;
213
2d8e6c8d 214 name = (char *)SvPV(ST(1),n_a);
6d4a7be2 215
54310121 216 ST(0) = boolSV(sv_derived_from(sv, name));
6d4a7be2
PP
217 XSRETURN(1);
218}
219
6d4a7be2
PP
220XS(XS_UNIVERSAL_can)
221{
222 dXSARGS;
223 SV *sv;
224 char *name;
225 SV *rv;
6f08146e 226 HV *pkg = NULL;
2d8e6c8d 227 STRLEN n_a;
6d4a7be2
PP
228
229 if (items != 2)
cea2e8a9 230 Perl_croak(aTHX_ "Usage: UNIVERSAL::can(object-ref, method)");
6d4a7be2
PP
231
232 sv = ST(0);
f8f70380 233
d3f7f2b2
GS
234 if (SvGMAGICAL(sv))
235 mg_get(sv);
236
aca069ec 237 if (!SvOK(sv) || !(SvROK(sv) || (SvPOK(sv) && SvCUR(sv))))
f8f70380
GS
238 XSRETURN_UNDEF;
239
2d8e6c8d 240 name = (char *)SvPV(ST(1),n_a);
3280af22 241 rv = &PL_sv_undef;
6d4a7be2 242
46e4b22b 243 if (SvROK(sv)) {
6f08146e 244 sv = (SV*)SvRV(sv);
46e4b22b 245 if (SvOBJECT(sv))
6f08146e
NIS
246 pkg = SvSTASH(sv);
247 }
248 else {
249 pkg = gv_stashsv(sv, FALSE);
250 }
251
252 if (pkg) {
dc848c6f
PP
253 GV *gv = gv_fetchmethod_autoload(pkg, name, FALSE);
254 if (gv && isGV(gv))
255 rv = sv_2mortal(newRV((SV*)GvCV(gv)));
6d4a7be2
PP
256 }
257
258 ST(0) = rv;
259 XSRETURN(1);
260}
261
6d4a7be2
PP
262XS(XS_UNIVERSAL_VERSION)
263{
264 dXSARGS;
265 HV *pkg;
266 GV **gvp;
267 GV *gv;
268 SV *sv;
269 char *undef;
270
1571675a 271 if (SvROK(ST(0))) {
6d4a7be2 272 sv = (SV*)SvRV(ST(0));
1571675a 273 if (!SvOBJECT(sv))
cea2e8a9 274 Perl_croak(aTHX_ "Cannot find version of an unblessed reference");
6d4a7be2
PP
275 pkg = SvSTASH(sv);
276 }
277 else {
278 pkg = gv_stashsv(ST(0), FALSE);
279 }
280
281 gvp = pkg ? (GV**)hv_fetch(pkg,"VERSION",7,FALSE) : Null(GV**);
282
d4bea2fb 283 if (gvp && isGV(gv = *gvp) && SvOK(sv = GvSV(gv))) {
6d4a7be2
PP
284 SV *nsv = sv_newmortal();
285 sv_setsv(nsv, sv);
286 sv = nsv;
287 undef = Nullch;
288 }
289 else {
3280af22 290 sv = (SV*)&PL_sv_undef;
6d4a7be2
PP
291 undef = "(undef)";
292 }
293
1571675a
GS
294 if (items > 1) {
295 STRLEN len;
296 SV *req = ST(1);
297
62658f4d
PM
298 if (undef) {
299 if (pkg)
300 Perl_croak(aTHX_
301 "%s does not define $%s::VERSION--version check failed",
302 HvNAME(pkg), HvNAME(pkg));
303 else {
304 char *str = SvPVx(ST(0), len);
305
306 Perl_croak(aTHX_
307 "%s defines neither package nor VERSION--version check failed", str);
308 }
309 }
1571675a
GS
310 if (!SvNIOK(sv) && SvPOK(sv)) {
311 char *str = SvPVx(sv,len);
312 while (len) {
313 --len;
314 /* XXX could DWIM "1.2.3" here */
315 if (!isDIGIT(str[len]) && str[len] != '.' && str[len] != '_')
316 break;
317 }
318 if (len) {
4305d8ab 319 if (SvNOK(req) && SvPOK(req)) {
1571675a
GS
320 /* they said C<use Foo v1.2.3> and $Foo::VERSION
321 * doesn't look like a float: do string compare */
322 if (sv_cmp(req,sv) == 1) {
d2560b70
RB
323 Perl_croak(aTHX_ "%s v%"VDf" required--"
324 "this is only v%"VDf,
1571675a
GS
325 HvNAME(pkg), req, sv);
326 }
327 goto finish;
328 }
329 /* they said C<use Foo 1.002_003> and $Foo::VERSION
330 * doesn't look like a float: force numeric compare */
155aba94 331 (void)SvUPGRADE(sv, SVt_PVNV);
1571675a
GS
332 SvNVX(sv) = str_to_version(sv);
333 SvPOK_off(sv);
334 SvNOK_on(sv);
335 }
336 }
337 /* if we get here, we're looking for a numeric comparison,
338 * so force the required version into a float, even if they
339 * said C<use Foo v1.2.3> */
4305d8ab 340 if (SvNOK(req) && SvPOK(req)) {
1571675a
GS
341 NV n = SvNV(req);
342 req = sv_newmortal();
343 sv_setnv(req, n);
344 }
345
f6eb1a96 346 if (SvNV(req) > SvNV(sv))
1571675a 347 Perl_croak(aTHX_ "%s version %s required--this is only version %s",
f6eb1a96 348 HvNAME(pkg), SvPV_nolen(req), SvPV_nolen(sv));
2d8e6c8d 349 }
6d4a7be2 350
1571675a 351finish:
6d4a7be2
PP
352 ST(0) = sv;
353
354 XSRETURN(1);
355}
356
1b026014
NIS
357XS(XS_utf8_valid)
358{
359 dXSARGS;
360 if (items != 1)
361 Perl_croak(aTHX_ "Usage: utf8::valid(sv)");
362 {
363 SV * sv = ST(0);
364 {
365 STRLEN len;
366 char *s = SvPV(sv,len);
367 if (!SvUTF8(sv) || is_utf8_string((U8*)s,len))
368 XSRETURN_YES;
369 else
370 XSRETURN_NO;
371 }
372 }
373 XSRETURN_EMPTY;
374}
375
376XS(XS_utf8_encode)
377{
378 dXSARGS;
379 if (items != 1)
380 Perl_croak(aTHX_ "Usage: utf8::encode(sv)");
381 {
382 SV * sv = ST(0);
383
384 sv_utf8_encode(sv);
385 }
386 XSRETURN_EMPTY;
387}
388
389XS(XS_utf8_decode)
390{
391 dXSARGS;
392 if (items != 1)
393 Perl_croak(aTHX_ "Usage: utf8::decode(sv)");
394 {
395 SV * sv = ST(0);
396 bool RETVAL;
397
398 RETVAL = sv_utf8_decode(sv);
399 ST(0) = boolSV(RETVAL);
400 sv_2mortal(ST(0));
401 }
402 XSRETURN(1);
403}
404
405XS(XS_utf8_upgrade)
406{
407 dXSARGS;
408 if (items != 1)
409 Perl_croak(aTHX_ "Usage: utf8::upgrade(sv)");
410 {
411 SV * sv = ST(0);
412 STRLEN RETVAL;
413 dXSTARG;
414
415 RETVAL = sv_utf8_upgrade(sv);
416 XSprePUSH; PUSHi((IV)RETVAL);
417 }
418 XSRETURN(1);
419}
420
421XS(XS_utf8_downgrade)
422{
423 dXSARGS;
424 if (items < 1 || items > 2)
425 Perl_croak(aTHX_ "Usage: utf8::downgrade(sv, failok=0)");
426 {
427 SV * sv = ST(0);
428 bool failok;
429 bool RETVAL;
430
431 if (items < 2)
432 failok = 0;
433 else {
434 failok = (int)SvIV(ST(1));
435 }
436
437 RETVAL = sv_utf8_downgrade(sv, failok);
438 ST(0) = boolSV(RETVAL);
439 sv_2mortal(ST(0));
440 }
441 XSRETURN(1);
442}
443
444XS(XS_utf8_native_to_unicode)
445{
446 dXSARGS;
447 UV uv = SvUV(ST(0));
b7953727
JH
448
449 if (items > 1)
450 Perl_croak(aTHX_ "Usage: utf8::native_to_unicode(sv)");
451
1b026014
NIS
452 ST(0) = sv_2mortal(newSViv(NATIVE_TO_UNI(uv)));
453 XSRETURN(1);
454}
455
456XS(XS_utf8_unicode_to_native)
457{
458 dXSARGS;
459 UV uv = SvUV(ST(0));
b7953727
JH
460
461 if (items > 1)
462 Perl_croak(aTHX_ "Usage: utf8::unicode_to_native(sv)");
463
1b026014
NIS
464 ST(0) = sv_2mortal(newSViv(UNI_TO_NATIVE(uv)));
465 XSRETURN(1);
466}
467
14a976d6 468XS(XS_Internals_SvREADONLY) /* This is dangerous stuff. */
29569577
JH
469{
470 dXSARGS;
471 SV *sv = SvRV(ST(0));
472 if (items == 1) {
473 if (SvREADONLY(sv))
474 XSRETURN_YES;
475 else
476 XSRETURN_NO;
477 }
478 else if (items == 2) {
479 if (SvTRUE(ST(1))) {
480 SvREADONLY_on(sv);
481 XSRETURN_YES;
482 }
483 else {
14a976d6 484 /* I hope you really know what you are doing. */
29569577
JH
485 SvREADONLY_off(sv);
486 XSRETURN_NO;
487 }
488 }
14a976d6 489 XSRETURN_UNDEF; /* Can't happen. */
29569577
JH
490}
491
14a976d6 492XS(XS_Internals_SvREFCNT) /* This is dangerous stuff. */
29569577
JH
493{
494 dXSARGS;
495 SV *sv = SvRV(ST(0));
496 if (items == 1)
14a976d6 497 XSRETURN_IV(SvREFCNT(sv) - 1); /* Minus the ref created for us. */
29569577 498 else if (items == 2) {
14a976d6 499 /* I hope you really know what you are doing. */
29569577
JH
500 SvREFCNT(sv) = SvIV(ST(1));
501 XSRETURN_IV(SvREFCNT(sv));
502 }
14a976d6 503 XSRETURN_UNDEF; /* Can't happen. */
29569577
JH
504}
505
dfd4ef2f
NC
506/* Maybe this should return the number of placeholders found in scalar context,
507 and a list of them in list context. */
508XS(XS_Internals_hv_clear_placeholders)
509{
510 dXSARGS;
511 HV *hv = (HV *) SvRV(ST(0));
512
513 /* I don't care how many parameters were passed in, but I want to avoid
514 the unused variable warning. */
515
516 items = HvPLACEHOLDERS(hv);
517
518 if (items) {
519 HE *entry;
520 I32 riter = HvRITER(hv);
521 HE *eiter = HvEITER(hv);
522 hv_iterinit(hv);
523 while (items
524 && (entry
525 = hv_iternext_flags(hv, HV_ITERNEXT_WANTPLACEHOLDERS))) {
526 SV *val = hv_iterval(hv, entry);
527
528 if (val == &PL_sv_undef) {
529
530 /* It seems that I have to go back in the front of the hash
531 API to delete a hash, even though I have a HE structure
532 pointing to the very entry I want to delete, and could hold
533 onto the previous HE that points to it. And it's easier to
534 go in with SVs as I can then specify the precomputed hash,
535 and don't have fun and games with utf8 keys. */
536 SV *key = hv_iterkeysv(entry);
537
538 hv_delete_ent (hv, key, G_DISCARD, HeHASH(entry));
539 items--;
540 }
541 }
542 HvRITER(hv) = riter;
543 HvEITER(hv) = eiter;
544 }
545
546 XSRETURN(0);
547}