1 /* This file is part of the Variable::Magic Perl module.
2 * See http://search.cpan.org/dist/Variable-Magic/ */
4 #include <stdlib.h> /* rand(), RAND_MAX */
5 #include <stdio.h> /* sprintf() */
7 #define PERL_NO_GET_CONTEXT
12 #define __PACKAGE__ "Variable::Magic"
14 #define R(S) fprintf(stderr, "R(" #S ") = %d\n", SvREFCNT(S))
16 /* --- Compatibility ------------------------------------------------------- */
19 # define Newx(v, n, c) New(0, v, n, c)
23 # define SvMAGIC_set(sv, val) (SvMAGIC(sv) = (val))
27 # define MY_CXT vmg_globaldata
29 # define START_MY_CXT STATIC my_cxt_t MY_CXT;
33 /* --- Context-safe global data -------------------------------------------- */
35 #define MY_CXT_KEY __PACKAGE__ "::_guts" XS_VERSION
44 /* --- Signatures ---------------------------------------------------------- */
46 #define SIG_MIN ((U16) (1u << 8))
47 #define SIG_MAX ((U16) (1u << 16 - 1))
48 #define SIG_NBR (SIG_MAX - SIG_MIN + 1)
49 #define SIG_WIZ ((U16) (1u << 8 - 1))
51 /* ... Generate signatures ................................................. */
53 STATIC U16 vmg_gensig(pTHX) {
54 #define vmg_gensig() vmg_gensig(aTHX)
60 double u = rand() / (RAND_MAX + 1.0);
61 sig = SIG_NBR * u + SIG_MIN;
62 } while (hv_exists(MY_CXT.wizz, buf, sprintf(buf, "%u", sig)));
67 /* --- MGWIZ structure ----------------------------------------------------- */
72 SV *cb_get, *cb_set, *cb_len, *cb_clear, *cb_free, *cb_data;
75 #define MGWIZ2SV(W) (newSVuv(PTR2UV(W)))
76 #define SV2MGWIZ(S) (INT2PTR(MGWIZ*, SvUVX((SV *) (S))))
78 /* ... Construct private data .............................................. */
80 STATIC SV *vmg_data_new(pTHX_ SV *ctor, SV *sv, AV *args) {
81 #define vmg_data_new(C, S, A) vmg_data_new(aTHX_ (C), (S), (A))
91 XPUSHs(sv_2mortal(newRV_inc(sv)));
93 I32 i, alen = av_len(args);
94 for (i = 0; i < alen; ++i) { XPUSHs(*av_fetch(args, i, 0)); }
98 count = call_sv(ctor, G_SCALAR);
102 if (count != 1) { croak("Callback needs to return 1 scalar\n"); }
104 SvREFCNT_inc(nsv); /* Or it will be destroyed in FREETMPS */
114 STATIC SV *vmg_data_get(SV *sv, U16 sig) {
115 MAGIC *mg, *moremagic;
118 if (SvTYPE(sv) >= SVt_PVMG) {
119 for (mg = SvMAGIC(sv); mg; mg = moremagic) {
120 moremagic = mg->mg_moremagic;
121 if ((mg->mg_type == PERL_MAGIC_ext) && (mg->mg_private == sig)) { break; }
123 if (mg) { return mg->mg_obj; }
129 /* ... Magic cast/dispell .................................................. */
131 STATIC UV vmg_cast(pTHX_ SV *sv, SV *wiz, AV *args) {
132 #define vmg_cast(S, W, A) vmg_cast(aTHX_ (S), (W), (A))
133 MAGIC *mg = NULL, *moremagic = NULL;
139 if (SvTYPE(sv) >= SVt_PVMG) {
140 for (mg = SvMAGIC(sv); mg; mg = moremagic) {
141 moremagic = mg->mg_moremagic;
142 if ((mg->mg_type == PERL_MAGIC_ext) && (mg->mg_private == w->sig)) { break; }
144 if (mg) { return 1; }
147 data = (w->cb_data) ? vmg_data_new(w->cb_data, sv, args) : NULL;
148 mg = sv_magicext(sv, data, PERL_MAGIC_ext, w->vtbl,
149 (const char *) wiz, HEf_SVKEY);
150 mg->mg_private = w->sig;
155 STATIC UV vmg_dispell(pTHX_ SV *sv, U16 sig) {
156 #define vmg_dispell(S, Z) vmg_dispell(aTHX_ (S), (Z))
157 MAGIC *mg, *prevmagic, *moremagic = NULL;
160 if (SvTYPE(sv) < SVt_PVMG) { return 0; }
162 for (prevmagic = NULL, mg = SvMAGIC(sv); mg; prevmagic = mg, mg = moremagic) {
163 moremagic = mg->mg_moremagic;
164 if ((mg->mg_type == PERL_MAGIC_ext) && (mg->mg_private == sig)) { break; }
166 if (!mg) { return 0; }
169 prevmagic->mg_moremagic = moremagic;
171 SvMAGIC_set(sv, moremagic);
173 mg->mg_moremagic = NULL;
175 if (mg->mg_obj != sv) { SvREFCNT_dec(mg->mg_obj); } /* Destroy private data */
176 SvREFCNT_dec((SV *) mg->mg_ptr); /* Unreference the wizard */
182 /* ... svt callbacks ....................................................... */
184 STATIC int vmg_cb_call(pTHX_ SV *cb, SV *sv, SV *data) {
185 #define vmg_cb_call(I, S, D) vmg_cb_call(aTHX_ (I), (S), (D))
195 XPUSHs(sv_2mortal(newRV_inc(sv)));
196 if (data) { XPUSHs(data); }
199 count = call_sv(cb, G_SCALAR);
203 if (count != 1) { croak("Callback needs to return 1 scalar\n"); }
214 STATIC int vmg_svt_get(pTHX_ SV *sv, MAGIC *mg) {
215 return vmg_cb_call(SV2MGWIZ(mg->mg_ptr)->cb_get, sv, mg->mg_obj);
218 STATIC int vmg_svt_set(pTHX_ SV *sv, MAGIC *mg) {
219 return vmg_cb_call(SV2MGWIZ(mg->mg_ptr)->cb_set, sv, mg->mg_obj);
222 STATIC U32 vmg_svt_len(pTHX_ SV *sv, MAGIC *mg) {
232 XPUSHs(sv_2mortal(newRV_inc(sv)));
233 XPUSHs((mg->mg_obj) ? (mg->mg_obj) : &PL_sv_undef);
234 if (SvTYPE(sv) == SVt_PVAV) {
235 XPUSHs(sv_2mortal(newSViv(av_len((AV *) sv) + 1)));
239 count = call_sv(SV2MGWIZ(mg->mg_ptr)->cb_len, G_SCALAR);
243 if (count != 1) { croak("Callback needs to return 1 scalar\n"); }
254 STATIC int vmg_svt_clear(pTHX_ SV *sv, MAGIC *mg) {
255 return vmg_cb_call(SV2MGWIZ(mg->mg_ptr)->cb_clear, sv, mg->mg_obj);
258 STATIC int vmg_svt_free(pTHX_ SV *sv, MAGIC *mg) {
259 /* So that it can survive tmp cleanup in vmg_cb_call */
261 /* Perl_mg_free will get rid of the magic and decrement mg->mg_obj and
262 * mg->mg_ptr reference count */
263 return vmg_cb_call(SV2MGWIZ(mg->mg_ptr)->cb_free, sv, mg->mg_obj);
266 /* ... Wizard destructor ................................................... */
268 STATIC int vmg_wizard_free(pTHX_ SV *wiz, MAGIC *mg) {
275 SvREFCNT_inc(wiz); /* Fake survival - it's gonna be deleted anyway */
276 #if PERL_API_REVISION >= 5 && PERL_API_VERSION >= 9 && PERL_API_SUBVERSION >= 5
277 SvREFCNT_inc(wiz); /* One more push */
279 if (hv_delete(MY_CXT.wizz, buf, sprintf(buf, "%u", w->sig), 0)) {
283 if (w->cb_get != NULL) { SvREFCNT_dec(SvRV(w->cb_get)); }
284 if (w->cb_set != NULL) { SvREFCNT_dec(SvRV(w->cb_set)); }
285 if (w->cb_len != NULL) { SvREFCNT_dec(SvRV(w->cb_len)); }
286 if (w->cb_clear != NULL) { SvREFCNT_dec(SvRV(w->cb_clear)); }
287 if (w->cb_free != NULL) { SvREFCNT_dec(SvRV(w->cb_free)); }
288 if (w->cb_data != NULL) { SvREFCNT_dec(SvRV(w->cb_data)); }
295 STATIC MGVTBL vmg_wizard_vtbl = {
300 vmg_wizard_free, /* free */
303 #endif /* MGf_COPY */
309 STATIC const char vmg_invalid_wiz[] = "Invalid wizard object";
310 STATIC const char vmg_invalid_sv[] = "Invalid variable";
311 STATIC const char vmg_invalid_sig[] = "Invalid numeric signature";
312 STATIC const char vmg_toomanysigs[] = "Too many magic signatures used";
313 STATIC const char vmg_argstorefailed[] = "Error while storing arguments";
315 STATIC U16 vmg_sv2sig(pTHX_ SV *sv) {
316 #define vmg_sv2sig(S) vmg_sv2sig(aTHX_ (S))
321 } else if (SvNOK(sv)) {
323 } else if ((SvPOK(sv) && grok_number(SvPVX(sv), SvCUR(sv), NULL))) {
326 croak(vmg_invalid_sig);
328 if (sig < SIG_MIN) { sig += SIG_MIN; }
329 if (sig > SIG_MAX) { sig %= SIG_MAX + 1; }
334 /* --- XS ------------------------------------------------------------------ */
336 MODULE = Variable::Magic PACKAGE = Variable::Magic
344 MY_CXT.wizz = newHV();
346 stash = gv_stashpv(__PACKAGE__, 1);
347 newCONSTSUB(stash, "SIG_MIN", newSVuv(SIG_MIN));
348 newCONSTSUB(stash, "SIG_MAX", newSVuv(SIG_MAX));
349 newCONSTSUB(stash, "SIG_NBR", newSVuv(SIG_NBR));
351 newCONSTSUB(stash, "MGf_COPY", newSVuv(MGf_COPY));
352 newCONSTSUB(stash, "MGf_DUP", newSVuv(MGf_DUP));
356 SV *_wizard(SV *svsig, SV *cb_get, SV *cb_set, SV *cb_len, SV *cb_clear, SV *cb_free, SV *cb_data)
369 sig = vmg_sv2sig(svsig);
370 if (old = hv_fetch(MY_CXT.wizz, buf, sprintf(buf, "%u", sig), 0)) {
371 ST(0) = sv_2mortal(newRV_inc(*old));
375 if (MY_CXT.count >= SIG_NBR) { croak(vmg_toomanysigs); }
380 t->svt_get = (SvOK(cb_get)) ? vmg_svt_get : NULL;
381 t->svt_set = (SvOK(cb_set)) ? vmg_svt_set : NULL;
382 t->svt_len = (SvOK(cb_len)) ? vmg_svt_len : NULL;
383 t->svt_clear = (SvOK(cb_clear)) ? vmg_svt_clear : NULL;
384 t->svt_free = (SvOK(cb_free)) ? vmg_svt_free : NULL;
387 #endif /* MGf_COPY */
395 w->cb_get = (SvROK(cb_get)) ? newRV_inc(SvRV(cb_get)) : NULL;
396 w->cb_set = (SvROK(cb_set)) ? newRV_inc(SvRV(cb_set)) : NULL;
397 w->cb_len = (SvROK(cb_len)) ? newRV_inc(SvRV(cb_len)) : NULL;
398 w->cb_clear = (SvROK(cb_clear)) ? newRV_inc(SvRV(cb_clear)) : NULL;
399 w->cb_free = (SvROK(cb_free)) ? newRV_inc(SvRV(cb_free)) : NULL;
400 w->cb_data = (SvROK(cb_data)) ? newRV_inc(SvRV(cb_data)) : NULL;
403 mg = sv_magicext(sv, NULL, PERL_MAGIC_ext, &vmg_wizard_vtbl, NULL, -1);
404 mg->mg_private = SIG_WIZ;
406 hv_store(MY_CXT.wizz, buf, sprintf(buf, "%u", sig), sv, 0);
409 RETVAL = newRV_noinc(sv);
417 if (MY_CXT.count >= SIG_NBR) { croak(vmg_toomanysigs); }
418 RETVAL = newSVuv(vmg_gensig());
425 if (!SvROK(wiz)) { croak(vmg_invalid_wiz); }
426 RETVAL = newSVuv(SV2MGWIZ(SvRV(wiz))->sig);
430 SV *cast(SV *sv, SV *wiz, ...)
431 PROTOTYPE: \[$@%&*]$@
439 } else if (SvOK(wiz)) {
442 U16 sig = vmg_sv2sig(wiz);
443 if (old = hv_fetch(MY_CXT.wizz, buf, sprintf(buf, "%u", sig), 0)) {
449 croak(vmg_invalid_sig);
454 av_fill(args, items - 2);
455 for (i = 2; i < items; ++i) {
458 if (av_store(args, i - 2, arg) == NULL) { croak(vmg_argstorefailed); }
461 ret = newSVuv(vmg_cast(SvRV(sv), wiz, args));
467 SV *getdata(SV *sv, SV *wiz)
475 sig = SV2MGWIZ(SvRV(wiz))->sig;
476 } else if (SvOK(wiz)) {
478 sig = vmg_sv2sig(wiz);
479 if (!hv_fetch(MY_CXT.wizz, buf, sprintf(buf, "%u", sig), 0)) {
483 croak(vmg_invalid_wiz);
485 data = vmg_data_get(SvRV(sv), sig);
486 if (!data) { XSRETURN_UNDEF; }
487 ST(0) = newSVsv(data);
490 SV *dispell(SV *sv, SV *wiz)
497 sig = SV2MGWIZ(SvRV(wiz))->sig;
498 } else if (SvOK(wiz)) {
500 sig = vmg_sv2sig(wiz);
501 if (!hv_fetch(MY_CXT.wizz, buf, sprintf(buf, "%u", sig), 0)) {
505 croak(vmg_invalid_wiz);
507 RETVAL = newSVuv(vmg_dispell(SvRV(sv), sig));