1 /* This file is part of the autovivification Perl module.
2 * See http://search.cpan.org/dist/autovivification/ */
4 #define PERL_NO_GET_CONTEXT
9 #define __PACKAGE__ "autovivification"
10 #define __PACKAGE_LEN__ (sizeof(__PACKAGE__)-1)
12 /* --- Compatibility wrappers ---------------------------------------------- */
14 #define A_HAS_PERL(R, V, S) (PERL_REVISION > (R) || (PERL_REVISION == (R) && (PERL_VERSION > (V) || (PERL_VERSION == (V) && (PERL_SUBVERSION >= (S))))))
16 #ifndef A_WORKAROUND_REQUIRE_PROPAGATION
17 # define A_WORKAROUND_REQUIRE_PROPAGATION !A_HAS_PERL(5, 10, 1)
20 /* --- Helpers ------------------------------------------------------------- */
22 #if A_WORKAROUND_REQUIRE_PROPAGATION
29 STATIC SV *a_tag(pTHX_ UV bits) {
30 #define a_tag(B) a_tag(aTHX_ (B))
40 for (si = PL_curstackinfo; si; si = si->si_prev) {
43 for (cxix = si->si_cxix; cxix >= 0; --cxix) {
44 const PERL_CONTEXT *cx = si->si_cxstack + cxix;
46 if (CxTYPE(cx) == CXt_EVAL && cx->blk_eval.old_op_type == OP_REQUIRE)
51 h.requires = requires;
54 return newSVpvn((const char *) &h, sizeof h);
57 STATIC UV a_detag(pTHX_ const SV *hint) {
58 #define a_detag(H) a_detag(aTHX_ (H))
61 if (!(hint && SvOK(hint)))
64 h = (const a_hint_t *) SvPVX(hint);
70 for (si = PL_curstackinfo; si; si = si->si_prev) {
73 for (cxix = si->si_cxix; cxix >= 0; --cxix) {
74 const PERL_CONTEXT *cx = si->si_cxstack + cxix;
76 if (CxTYPE(cx) == CXt_EVAL && cx->blk_eval.old_op_type == OP_REQUIRE
77 && ++requires > h->requires)
86 #else /* A_WORKAROUND_REQUIRE_PROPAGATION */
88 #define a_tag(B) newSVuv(B)
89 #define a_detag(H) (((H) && SvOK(H)) ? SvUVX(H) : 0)
91 #endif /* !A_WORKAROUND_REQUIRE_PROPAGATION */
93 /* Used both for hints and op flags */
94 #define A_HINT_STRICT 1
96 #define A_HINT_FETCH 4
97 #define A_HINT_STORE 8
98 #define A_HINT_EXISTS 16
99 #define A_HINT_DELETE 32
100 #define A_HINT_NOTIFY (A_HINT_STRICT|A_HINT_WARN)
101 #define A_HINT_DO (A_HINT_FETCH|A_HINT_STORE|A_HINT_EXISTS|A_HINT_DELETE)
102 #define A_HINT_MASK (A_HINT_NOTIFY|A_HINT_DO)
104 /* Only used in op flags */
105 #define A_HINT_DEREF 64
107 STATIC U32 a_hash = 0;
109 STATIC UV a_hint(pTHX) {
110 #define a_hint() a_hint(aTHX)
112 #if A_HAS_PERL(5, 9, 5)
113 hint = Perl_refcounted_he_fetch(aTHX_ PL_curcop->cop_hints_hash,
115 __PACKAGE__, __PACKAGE_LEN__,
119 SV **val = hv_fetch(GvHV(PL_hintgv), __PACKAGE__, __PACKAGE_LEN__, a_hash);
124 return a_detag(hint);
127 /* ... op => info map ...................................................... */
135 #define PTABLE_NAME ptable_map
136 #define PTABLE_VAL_FREE(V) PerlMemShared_free(V)
140 /* PerlMemShared_free() needs the [ap]PTBLMS_? default values */
141 #define ptable_map_store(T, K, V) ptable_map_store(aPTBLMS_ (T), (K), (V))
143 STATIC ptable *a_op_map = NULL;
146 STATIC perl_mutex a_op_map_mutex;
149 STATIC void a_map_store(pPTBLMS_ const OP *o, OP *(*old_pp)(pTHX), UV flags) {
150 #define a_map_store(O, PP, F) a_map_store(aPTBLMS_ (O), (PP), (F))
154 MUTEX_LOCK(&a_op_map_mutex);
157 if (!(oi = ptable_fetch(a_op_map, o))) {
158 oi = PerlMemShared_malloc(sizeof *oi);
159 ptable_map_store(a_op_map, o, oi);
167 MUTEX_UNLOCK(&a_op_map_mutex);
171 STATIC const a_op_info *a_map_fetch(const OP *o, a_op_info *oi) {
172 const a_op_info *val;
175 MUTEX_LOCK(&a_op_map_mutex);
178 val = ptable_fetch(a_op_map, o);
186 MUTEX_UNLOCK(&a_op_map_mutex);
192 STATIC void a_map_delete(pTHX_ const OP *o) {
193 #define a_map_delete(O) a_map_delete(aTHX_ (O))
195 MUTEX_LOCK(&a_op_map_mutex);
198 ptable_map_store(a_op_map, o, NULL);
201 MUTEX_UNLOCK(&a_op_map_mutex);
205 STATIC void a_map_set_root(const OP *root, UV flags) {
210 MUTEX_LOCK(&a_op_map_mutex);
214 if (oi = ptable_fetch(a_op_map, o)) {
218 if (!(o->op_flags & OPf_KIDS))
220 o = cUNOPo->op_first;
224 MUTEX_UNLOCK(&a_op_map_mutex);
228 /* ... Lightweight pp_defined() ............................................ */
230 STATIC bool a_defined(pTHX_ SV *sv) {
231 #define a_defined(S) a_defined(aTHX_ (S))
232 bool defined = FALSE;
234 switch (SvTYPE(sv)) {
236 if (AvMAX(sv) >= 0 || SvGMAGICAL(sv)
237 || (SvRMAGICAL(sv) && mg_find(sv, PERL_MAGIC_tied)))
241 if (HvARRAY(sv) || SvGMAGICAL(sv)
242 || (SvRMAGICAL(sv) && mg_find(sv, PERL_MAGIC_tied)))
252 /* --- PP functions -------------------------------------------------------- */
254 /* ... pp_rv2av ............................................................ */
256 STATIC OP *a_pp_rv2av(pTHX) {
262 /* We always need to push an empty array to fool the pp_aelem() that comes
266 av = sv_2mortal((SV *) newAV());
271 a_map_fetch(PL_op, &oi);
273 return CALL_FPTR(oi.old_pp)(aTHX);
276 /* ... pp_rv2hv ............................................................ */
278 STATIC OP *a_pp_rv2hv(pTHX) {
283 a_map_fetch(PL_op, &oi);
286 if (oi.root->op_flags & OPf_MOD) {
289 hv = sv_2mortal((SV *) newHV());
295 return CALL_FPTR(oi.old_pp)(aTHX);
298 /* ... pp_deref (aelem,helem,rv2sv,padsv) .................................. */
300 STATIC const char a_msg_forbidden[] = "Reference vivification forbidden";
301 STATIC const char a_msg_impossible[] = "Can't vivify reference";
303 STATIC OP *a_pp_deref(pTHX) {
308 a_map_fetch(PL_op, &oi);
311 if (flags & A_HINT_DEREF) {
316 old_private = PL_op->op_private;
317 PL_op->op_private = ((old_private & ~OPpDEREF) | OPpLVAL_DEFER);
318 o = CALL_FPTR(oi.old_pp)(aTHX);
319 PL_op->op_private = old_private;
321 if (flags & (A_HINT_NOTIFY|A_HINT_STORE)) {
324 if (flags & A_HINT_STRICT)
325 croak(a_msg_forbidden);
326 else if (flags & A_HINT_WARN)
327 warn(a_msg_forbidden);
328 else /* A_HINT_STORE */
329 croak(a_msg_impossible);
334 } else if (flags && (PL_op->op_private & OPpDEREF || PL_op == oi.root)) {
335 oi.flags = flags & A_HINT_NOTIFY;
337 if ((oi.root->op_flags & (OPf_MOD|OPf_REF)) != (OPf_MOD|OPf_REF)) {
338 if (flags & A_HINT_FETCH)
339 oi.flags |= (A_HINT_FETCH|A_HINT_DEREF);
340 } else if (flags & A_HINT_STORE)
341 oi.flags |= (A_HINT_STORE|A_HINT_DEREF);
343 if (PL_op == oi.root)
344 oi.flags &= ~A_HINT_DEREF;
346 /* We will need the updated flags value in the deref part */
349 if (flags & A_HINT_DEREF)
352 /* This op doesn't need to skip autovivification, so restore the original
353 * state. Be aware that another extension might have saved a_pp_deref as the
354 * ppaddr for this op, so restoring PL_op->op_ppaddr doesn't ensure that this
355 * function will never be called again. That's why we don't remove the op info
356 * from our map and we reset oi.flags to 0, so that it can still run correctly
359 PL_op->op_ppaddr = oi.old_pp;
362 return CALL_FPTR(oi.old_pp)(aTHX);
365 /* ... pp_root (exists,delete) ............................................. */
367 STATIC OP *a_pp_root(pTHX) {
371 if (!a_defined(TOPm1s)) {
374 if (PL_op->op_type == OP_EXISTS)
380 a_map_fetch(PL_op, &oi);
382 return CALL_FPTR(oi.old_pp)(aTHX);
385 /* --- Check functions ----------------------------------------------------- */
387 /* ... ck_pad{any,sv} ...................................................... */
389 /* Sadly, the PADSV OPs we are interested in don't trigger the padsv check
390 * function, but are instead manually mutated from a PADANY. This is why we set
391 * PL_ppaddr[OP_PADSV] in the padany check function so that PADSV OPs will have
392 * their op_ppaddr set to our pp_padsv. PL_ppaddr[OP_PADSV] is then reset at the
393 * beginning of every ck_pad{any,sv}. Some unwanted OPs can still call our
394 * pp_padsv, but much less than if we would have set PL_ppaddr[OP_PADSV]
397 STATIC OP *(*a_pp_padsv_saved)(pTHX) = 0;
399 STATIC void a_pp_padsv_save(void) {
400 if (a_pp_padsv_saved)
403 a_pp_padsv_saved = PL_ppaddr[OP_PADSV];
404 PL_ppaddr[OP_PADSV] = a_pp_deref;
407 STATIC void a_pp_padsv_restore(OP *o) {
408 if (!a_pp_padsv_saved)
411 if (o->op_ppaddr == a_pp_deref)
412 o->op_ppaddr = a_pp_padsv_saved;
414 PL_ppaddr[OP_PADSV] = a_pp_padsv_saved;
415 a_pp_padsv_saved = 0;
418 STATIC OP *(*a_old_ck_padany)(pTHX_ OP *) = 0;
420 STATIC OP *a_ck_padany(pTHX_ OP *o) {
423 a_pp_padsv_restore(o);
425 o = CALL_FPTR(a_old_ck_padany)(aTHX_ o);
428 if (hint & A_HINT_DO) {
430 a_map_store(o, a_pp_padsv_saved, hint);
437 STATIC OP *(*a_old_ck_padsv)(pTHX_ OP *) = 0;
439 STATIC OP *a_ck_padsv(pTHX_ OP *o) {
442 a_pp_padsv_restore(o);
444 o = CALL_FPTR(a_old_ck_padsv)(aTHX_ o);
447 if (hint & A_HINT_DO) {
448 a_map_store(o, o->op_ppaddr, hint);
449 o->op_ppaddr = a_pp_deref;
456 /* ... ck_deref (aelem,helem,rv2sv) ........................................ */
458 STATIC OP *(*a_old_ck_aelem)(pTHX_ OP *) = 0;
459 STATIC OP *(*a_old_ck_helem)(pTHX_ OP *) = 0;
460 STATIC OP *(*a_old_ck_rv2sv)(pTHX_ OP *) = 0;
462 STATIC OP *a_ck_deref(pTHX_ OP *o) {
463 OP * (*old_ck)(pTHX_ OP *o) = 0;
466 switch (o->op_type) {
467 case OP_AELEM: old_ck = a_old_ck_aelem; break;
468 case OP_HELEM: old_ck = a_old_ck_helem; break;
469 case OP_RV2SV: old_ck = a_old_ck_rv2sv; break;
471 o = CALL_FPTR(old_ck)(aTHX_ o);
474 if (hint & A_HINT_DO) {
475 if (!(hint & A_HINT_STRICT) && o->op_flags & OPf_KIDS) {
476 OP *kid = cUNOPo->op_first;
477 switch (kid->op_type) {
479 a_map_store(kid, kid->op_ppaddr, hint);
480 kid->op_ppaddr = a_pp_rv2av;
483 a_map_store(kid, kid->op_ppaddr, hint);
484 kid->op_ppaddr = a_pp_rv2hv;
488 a_map_store(o, o->op_ppaddr, hint);
489 o->op_ppaddr = a_pp_deref;
490 a_map_set_root(o, hint);
497 /* ... ck_root (exists,delete) ............................................. */
499 STATIC OP *(*a_old_ck_exists)(pTHX_ OP *) = 0;
500 STATIC OP *(*a_old_ck_delete)(pTHX_ OP *) = 0;
502 STATIC OP *a_ck_root(pTHX_ OP *o) {
503 OP * (*old_ck)(pTHX_ OP *o) = 0;
504 bool enabled = FALSE;
507 switch (o->op_type) {
509 old_ck = a_old_ck_exists;
510 enabled = hint & A_HINT_EXISTS;
513 old_ck = a_old_ck_delete;
514 enabled = hint & A_HINT_DELETE;
517 o = CALL_FPTR(old_ck)(aTHX_ o);
520 a_map_set_root(o, hint | A_HINT_DEREF);
521 a_map_store(o, o->op_ppaddr, hint);
522 o->op_ppaddr = a_pp_root;
524 a_map_set_root(o, 0);
530 STATIC U32 a_initialized = 0;
532 /* --- XS ------------------------------------------------------------------ */
534 MODULE = autovivification PACKAGE = autovivification
540 if (!a_initialized++) {
543 a_op_map = ptable_new();
545 MUTEX_INIT(&a_op_map_mutex);
548 PERL_HASH(a_hash, __PACKAGE__, __PACKAGE_LEN__);
550 a_old_ck_padany = PL_check[OP_PADANY];
551 PL_check[OP_PADANY] = MEMBER_TO_FPTR(a_ck_padany);
552 a_old_ck_padsv = PL_check[OP_PADSV];
553 PL_check[OP_PADSV] = MEMBER_TO_FPTR(a_ck_padsv);
554 a_old_ck_aelem = PL_check[OP_AELEM];
555 PL_check[OP_AELEM] = MEMBER_TO_FPTR(a_ck_deref);
556 a_old_ck_helem = PL_check[OP_HELEM];
557 PL_check[OP_HELEM] = MEMBER_TO_FPTR(a_ck_deref);
558 a_old_ck_rv2sv = PL_check[OP_RV2SV];
559 PL_check[OP_RV2SV] = MEMBER_TO_FPTR(a_ck_deref);
560 a_old_ck_exists = PL_check[OP_EXISTS];
561 PL_check[OP_EXISTS] = MEMBER_TO_FPTR(a_ck_root);
562 a_old_ck_delete = PL_check[OP_DELETE];
563 PL_check[OP_DELETE] = MEMBER_TO_FPTR(a_ck_root);
565 stash = gv_stashpvn(__PACKAGE__, __PACKAGE_LEN__, 1);
566 newCONSTSUB(stash, "A_HINT_STRICT", newSVuv(A_HINT_STRICT));
567 newCONSTSUB(stash, "A_HINT_WARN", newSVuv(A_HINT_WARN));
568 newCONSTSUB(stash, "A_HINT_FETCH", newSVuv(A_HINT_FETCH));
569 newCONSTSUB(stash, "A_HINT_STORE", newSVuv(A_HINT_STORE));
570 newCONSTSUB(stash, "A_HINT_EXISTS", newSVuv(A_HINT_EXISTS));
571 newCONSTSUB(stash, "A_HINT_DELETE", newSVuv(A_HINT_DELETE));
572 newCONSTSUB(stash, "A_HINT_MASK", newSVuv(A_HINT_MASK));
580 RETVAL = a_tag(SvOK(hint) ? SvUV(hint) : 0);
590 RETVAL = newSVuv(a_detag(tag));