X-Git-Url: https://perl5.git.perl.org/perl5.git/blobdiff_plain/1e9bd1186a044d6e3506ed14fbe055b8f75f7641..2f14ddcd0c64ac3c80bca49bad0af9734d9f6c6b:/mro.c diff --git a/mro.c b/mro.c index c29d38e..cb67950 100644 --- a/mro.c +++ b/mro.c @@ -1,7 +1,7 @@ /* mro.c * * Copyright (c) 2007 Brandon L Black - * Copyright (c) 2007, 2008 Larry Wall and others + * Copyright (c) 2007, 2008, 2009, 2010, 2011 Larry Wall and others * * You may distribute under the terms of either the GNU General Public * License or the Artistic License, as specified in the README file. @@ -37,9 +37,9 @@ Perl_mro_get_private_data(pTHX_ struct mro_meta *const smeta, SV **data; PERL_ARGS_ASSERT_MRO_GET_PRIVATE_DATA; - data = Perl_hv_common(aTHX_ smeta->mro_linear_all, NULL, - which->name, which->length, which->kflags, - HV_FETCH_JUST_SV, NULL, which->hash); + data = (SV **)Perl_hv_common(aTHX_ smeta->mro_linear_all, NULL, + which->name, which->length, which->kflags, + HV_FETCH_JUST_SV, NULL, which->hash); if (!data) return NULL; @@ -105,8 +105,8 @@ Perl_mro_get_from_name(pTHX_ SV *name) { PERL_ARGS_ASSERT_MRO_GET_FROM_NAME; - data = Perl_hv_common(aTHX_ PL_registered_mros, name, NULL, 0, 0, - HV_FETCH_JUST_SV, NULL, 0); + data = (SV **)Perl_hv_common(aTHX_ PL_registered_mros, name, NULL, 0, 0, + HV_FETCH_JUST_SV, NULL, 0); if (!data) return NULL; assert(SvTYPE(*data) == SVt_IV); @@ -114,6 +114,13 @@ Perl_mro_get_from_name(pTHX_ SV *name) { return INT2PTR(const struct mro_alg *, SvUVX(*data)); } +/* +=for apidoc mro_register +Registers a custom mro plugin. See L for details. + +=cut +*/ + void Perl_mro_register(pTHX_ const struct mro_alg *mro) { SV *wrapper = newSVuv(PTR2UV(mro)); @@ -124,7 +131,7 @@ Perl_mro_register(pTHX_ const struct mro_alg *mro) { if (!Perl_hv_common(aTHX_ PL_registered_mros, NULL, mro->name, mro->length, mro->kflags, HV_FETCH_ISSTORE, wrapper, mro->hash)) { - SvREFCNT_dec(wrapper); + SvREFCNT_dec_NN(wrapper); Perl_croak(aTHX_ "panic: hv_store() failed in mro_register() " "for '%.*s' %d", (int) mro->length, mro->name, mro->kflags); } @@ -162,64 +169,28 @@ Perl_mro_meta_dup(pTHX_ struct mro_meta* smeta, CLONE_PARAMS* param) if (newmeta->mro_linear_all) { newmeta->mro_linear_all - = MUTABLE_HV(SvREFCNT_inc(sv_dup((const SV *)newmeta->mro_linear_all, param))); + = MUTABLE_HV(sv_dup_inc((const SV *)newmeta->mro_linear_all, param)); /* This is just acting as a shortcut pointer, and will be automatically updated on the first get. */ newmeta->mro_linear_current = NULL; } else if (newmeta->mro_linear_current) { /* Only the current MRO is stored, so this owns the data. */ newmeta->mro_linear_current - = SvREFCNT_inc(sv_dup((const SV *)newmeta->mro_linear_current, - param)); + = sv_dup_inc((const SV *)newmeta->mro_linear_current, param); } if (newmeta->mro_nextmethod) newmeta->mro_nextmethod - = MUTABLE_HV(SvREFCNT_inc(sv_dup((const SV *)newmeta->mro_nextmethod, param))); + = MUTABLE_HV(sv_dup_inc((const SV *)newmeta->mro_nextmethod, param)); if (newmeta->isa) newmeta->isa - = MUTABLE_HV(SvREFCNT_inc(sv_dup((const SV *)newmeta->isa, param))); + = MUTABLE_HV(sv_dup_inc((const SV *)newmeta->isa, param)); return newmeta; } #endif /* USE_ITHREADS */ -HV * -Perl_get_isa_hash(pTHX_ HV *const stash) -{ - dVAR; - struct mro_meta *const meta = HvMROMETA(stash); - - PERL_ARGS_ASSERT_GET_ISA_HASH; - - if (!meta->isa) { - AV *const isa = mro_get_linear_isa(stash); - if (!meta->isa) { - HV *const isa_hash = newHV(); - /* Linearisation didn't build it for us, so do it here. */ - SV *const *svp = AvARRAY(isa); - SV *const *const svp_end = svp + AvFILLp(isa) + 1; - const HEK *const canon_name = HvNAME_HEK(stash); - - while (svp < svp_end) { - (void) hv_store_ent(isa_hash, *svp++, &PL_sv_undef, 0); - } - - (void) hv_common(isa_hash, NULL, HEK_KEY(canon_name), - HEK_LEN(canon_name), HEK_FLAGS(canon_name), - HV_FETCH_ISSTORE, &PL_sv_undef, - HEK_HASH(canon_name)); - (void) hv_store(isa_hash, "UNIVERSAL", 9, &PL_sv_undef, 0); - - SvREADONLY_on(isa_hash); - - meta->isa = isa_hash; - } - } - return meta->isa; -} - /* =for apidoc mro_get_linear_isa_dfs @@ -246,18 +217,23 @@ S_mro_get_linear_isa_dfs(pTHX_ HV *stash, U32 level) const HEK* stashhek; struct mro_meta* meta; SV *our_name; - HV *stored; + HV *stored = NULL; PERL_ARGS_ASSERT_MRO_GET_LINEAR_ISA_DFS; assert(HvAUX(stash)); - stashhek = HvNAME_HEK(stash); + stashhek + = HvAUX(stash)->xhv_name_u.xhvnameu_name && HvENAME_HEK_NN(stash) + ? HvENAME_HEK_NN(stash) + : HvNAME_HEK(stash); + if (!stashhek) Perl_croak(aTHX_ "Can't linearize anonymous symbol table"); if (level > 100) - Perl_croak(aTHX_ "Recursive inheritance detected in package '%s'", - HEK_KEY(stashhek)); + Perl_croak(aTHX_ + "Recursive inheritance detected in package '%"HEKf"'", + HEKfARG(stashhek)); meta = HvMROMETA(stash); @@ -284,8 +260,6 @@ S_mro_get_linear_isa_dfs(pTHX_ HV *stash, U32 level) It's then retained to be re-used as a fast lookup for ->isa(), by adding our own name and "UNIVERSAL" to it. */ - stored = MUTABLE_HV(sv_2mortal(MUTABLE_SV(newHV()))); - if(av && AvFILLp(av) >= 0) { SV **svp = AvARRAY(av); @@ -316,41 +290,78 @@ S_mro_get_linear_isa_dfs(pTHX_ HV *stash, U32 level) subrv_p = AvARRAY(subrv); subrv_items = AvFILLp(subrv) + 1; } - while(subrv_items--) { - SV *const subsv = *subrv_p++; - /* LVALUE fetch will create a new undefined SV if necessary - */ - HE *const he = hv_fetch_ent(stored, subsv, 1, 0); - assert(he); - if(HeVAL(he) != &PL_sv_undef) { - /* It was newly created. Steal it for our new SV, and - replace it in the hash with the "real" thing. */ - SV *const val = HeVAL(he); - HEK *const key = HeKEY_hek(he); - - HeVAL(he) = &PL_sv_undef; - /* Save copying by making a shared hash key scalar. We - inline this here rather than calling Perl_newSVpvn_share - because we already have the scalar, and we already have - the hash key. */ - assert(SvTYPE(val) == SVt_NULL); - sv_upgrade(val, SVt_PV); - SvPV_set(val, HEK_KEY(share_hek_hek(key))); - SvCUR_set(val, HEK_LEN(key)); - SvREADONLY_on(val); - SvFAKE_on(val); - SvPOK_on(val); - if (HEK_UTF8(key)) - SvUTF8_on(val); - - av_push(retval, val); + if (stored) { + while(subrv_items--) { + SV *const subsv = *subrv_p++; + /* LVALUE fetch will create a new undefined SV if necessary + */ + HE *const he = hv_fetch_ent(stored, subsv, 1, 0); + assert(he); + if(HeVAL(he) != &PL_sv_undef) { + /* It was newly created. Steal it for our new SV, and + replace it in the hash with the "real" thing. */ + SV *const val = HeVAL(he); + HEK *const key = HeKEY_hek(he); + + HeVAL(he) = &PL_sv_undef; + /* Save copying by making a shared hash key scalar. We + inline this here rather than calling + Perl_newSVpvn_share because we already have the + scalar, and we already have the hash key. */ + assert(SvTYPE(val) == SVt_NULL); + sv_upgrade(val, SVt_PV); + SvPV_set(val, HEK_KEY(share_hek_hek(key))); + SvCUR_set(val, HEK_LEN(key)); + SvIsCOW_on(val); + SvPOK_on(val); + if (HEK_UTF8(key)) + SvUTF8_on(val); + + av_push(retval, val); + } } - } + } else { + /* We are the first (or only) parent. We can short cut the + complexity above, because our @ISA is simply us prepended + to our parent's @ISA, and our ->isa cache is simply our + parent's, with our name added. */ + /* newSVsv() is slow. This code is only faster if we can avoid + it by ensuring that SVs in the arrays are shared hash key + scalar SVs, because we can "copy" them very efficiently. + Although to be fair, we can't *ensure* this, as a reference + to the internal array is returned by mro::get_linear_isa(), + so we'll have to be defensive just in case someone faffed + with it. */ + if (basestash) { + SV **svp; + stored = MUTABLE_HV(sv_2mortal((SV*)newHVhv(HvMROMETA(basestash)->isa))); + av_extend(retval, subrv_items); + AvFILLp(retval) = subrv_items; + svp = AvARRAY(retval); + while(subrv_items--) { + SV *const val = *subrv_p++; + *++svp = SvIsCOW_shared_hash(val) + ? newSVhek(SvSHARED_HEK_FROM_PV(SvPVX(val))) + : newSVsv(val); + } + } else { + /* They have no stash. So create ourselves an ->isa cache + as if we'd copied it from what theirs should be. */ + stored = MUTABLE_HV(sv_2mortal(MUTABLE_SV(newHV()))); + (void) hv_store(stored, "UNIVERSAL", 9, &PL_sv_undef, 0); + av_push(retval, + newSVhek(HeKEY_hek(hv_store_ent(stored, sv, + &PL_sv_undef, 0)))); + } + } } + } else { + /* We have no parents. */ + stored = MUTABLE_HV(sv_2mortal(MUTABLE_SV(newHV()))); + (void) hv_store(stored, "UNIVERSAL", 9, &PL_sv_undef, 0); } (void) hv_store_ent(stored, our_name, &PL_sv_undef, 0); - (void) hv_store(stored, "UNIVERSAL", 9, &PL_sv_undef, 0); SvREFCNT_inc_simple_void_NN(stored); SvTEMP_off(stored); @@ -375,10 +386,9 @@ S_mro_get_linear_isa_dfs(pTHX_ HV *stash, U32 level) /* =for apidoc mro_get_linear_isa -Returns either C or -C for the given stash, -dependant upon which MRO is in effect -for that stash. The return value is a +Returns the mro linearisation for the given stash. By default, this +will be whatever C returns unless some +other MRO is in effect for the stash. The return value is a read-only AV*. You are responsible for C on the @@ -393,6 +403,7 @@ AV* Perl_mro_get_linear_isa(pTHX_ HV *stash) { struct mro_meta* meta; + AV *isa; PERL_ARGS_ASSERT_MRO_GET_LINEAR_ISA; if(!SvOOK(stash)) @@ -401,7 +412,55 @@ Perl_mro_get_linear_isa(pTHX_ HV *stash) meta = HvMROMETA(stash); if (!meta->mro_which) Perl_croak(aTHX_ "panic: invalid MRO!"); - return meta->mro_which->resolve(aTHX_ stash, 0); + isa = meta->mro_which->resolve(aTHX_ stash, 0); + + if (meta->mro_which != &dfs_alg) { /* skip for dfs, for speed */ + SV * const namesv = + (HvENAME(stash)||HvNAME(stash)) + ? newSVhek(HvENAME_HEK(stash) + ? HvENAME_HEK(stash) + : HvNAME_HEK(stash)) + : NULL; + + if(namesv && (AvFILLp(isa) == -1 || !sv_eq(*AvARRAY(isa), namesv))) + { + AV * const old = isa; + SV **svp; + SV **ovp = AvARRAY(old); + SV * const * const oend = ovp + AvFILLp(old) + 1; + isa = (AV *)sv_2mortal((SV *)newAV()); + av_extend(isa, AvFILLp(isa) = AvFILLp(old)+1); + *AvARRAY(isa) = namesv; + svp = AvARRAY(isa)+1; + while (ovp < oend) *svp++ = SvREFCNT_inc(*ovp++); + } + else SvREFCNT_dec(namesv); + } + + if (!meta->isa) { + HV *const isa_hash = newHV(); + /* Linearisation didn't build it for us, so do it here. */ + SV *const *svp = AvARRAY(isa); + SV *const *const svp_end = svp + AvFILLp(isa) + 1; + const HEK *canon_name = HvENAME_HEK(stash); + if (!canon_name) canon_name = HvNAME_HEK(stash); + + while (svp < svp_end) { + (void) hv_store_ent(isa_hash, *svp++, &PL_sv_undef, 0); + } + + (void) hv_common(isa_hash, NULL, HEK_KEY(canon_name), + HEK_LEN(canon_name), HEK_FLAGS(canon_name), + HV_FETCH_ISSTORE, &PL_sv_undef, + HEK_HASH(canon_name)); + (void) hv_store(isa_hash, "UNIVERSAL", 9, &PL_sv_undef, 0); + + SvREADONLY_on(isa_hash); + + meta->isa = isa_hash; + } + + return isa; } /* @@ -413,6 +472,20 @@ by the C magic, should not need to invoke directly. =cut */ + +/* Macro to avoid repeating the code five times. */ +#define CLEAR_LINEAR(mEta) \ + if (mEta->mro_linear_all) { \ + SvREFCNT_dec(MUTABLE_SV(mEta->mro_linear_all)); \ + mEta->mro_linear_all = NULL; \ + /* This is just acting as a shortcut pointer. */ \ + mEta->mro_linear_current = NULL; \ + } else if (mEta->mro_linear_current) { \ + /* Only the current MRO is stored, so this owns the data. */ \ + SvREFCNT_dec(mEta->mro_linear_current); \ + mEta->mro_linear_current = NULL; \ + } + void Perl_mro_isa_changed_in(pTHX_ HV* stash) { @@ -424,29 +497,24 @@ Perl_mro_isa_changed_in(pTHX_ HV* stash) I32 items; bool is_universal; struct mro_meta * meta; + HV *isa = NULL; - const char * const stashname = HvNAME_get(stash); - const STRLEN stashname_len = HvNAMELEN_get(stash); + const char * const stashname = HvENAME_get(stash); + const STRLEN stashname_len = HvENAMELEN_get(stash); + const bool stashname_utf8 = HvENAMEUTF8(stash) ? 1 : 0; PERL_ARGS_ASSERT_MRO_ISA_CHANGED_IN; if(!stashname) Perl_croak(aTHX_ "Can't call mro_isa_changed_in() on anonymous symbol table"); + /* wipe out the cached linearizations for this stash */ meta = HvMROMETA(stash); - if (meta->mro_linear_all) { - SvREFCNT_dec(MUTABLE_SV(meta->mro_linear_all)); - meta->mro_linear_all = NULL; - /* This is just acting as a shortcut pointer. */ - meta->mro_linear_current = NULL; - } else if (meta->mro_linear_current) { - /* Only the current MRO is stored, so this owns the data. */ - SvREFCNT_dec(meta->mro_linear_current); - meta->mro_linear_current = NULL; - } + CLEAR_LINEAR(meta); if (meta->isa) { - SvREFCNT_dec(meta->isa); + /* Steal it for our own purposes. */ + isa = (HV *)sv_2mortal((SV *)meta->isa); meta->isa = NULL; } @@ -456,7 +524,8 @@ Perl_mro_isa_changed_in(pTHX_ HV* stash) /* Wipe the global method cache if this package is UNIVERSAL or one of its parents */ - svp = hv_fetch(PL_isarev, stashname, stashname_len, 0); + svp = hv_fetch(PL_isarev, stashname, + stashname_utf8 ? -(I32)stashname_len : (I32)stashname_len, 0); isarev = svp ? MUTABLE_HV(*svp) : NULL; if((stashname_len == 9 && strEQ(stashname, "UNIVERSAL")) @@ -472,39 +541,114 @@ Perl_mro_isa_changed_in(pTHX_ HV* stash) /* wipe next::method cache too */ if(meta->mro_nextmethod) hv_clear(meta->mro_nextmethod); + /* Changes to @ISA might turn overloading on */ + HvAMAGIC_on(stash); + + /* DESTROY can be cached in SvSTASH. */ + if (!SvOBJECT(stash)) SvSTASH(stash) = NULL; + /* Iterate the isarev (classes that are our children), - wiping out their linearization and method caches */ + wiping out their linearization, method and isa caches + and upating PL_isarev. */ if(isarev) { - hv_iterinit(isarev); + HV *isa_hashes = NULL; + + /* We have to iterate through isarev twice to avoid a chicken and + * egg problem: if A inherits from B and both are in isarev, A might + * be processed before B and use B's previous linearisation. + */ + + /* First iteration: Wipe everything, but stash away the isa hashes + * since we still need them for updating PL_isarev. + */ + + if(hv_iterinit(isarev)) { + /* Only create the hash if we need it; i.e., if isarev has + any elements. */ + isa_hashes = (HV *)sv_2mortal((SV *)newHV()); + } while((iter = hv_iternext(isarev))) { - I32 len; - const char* const revkey = hv_iterkey(iter, &len); - HV* revstash = gv_stashpvn(revkey, len, 0); + HV* revstash = gv_stashsv(hv_iterkeysv(iter), 0); struct mro_meta* revmeta; if(!revstash) continue; revmeta = HvMROMETA(revstash); - if (revmeta->mro_linear_all) { - SvREFCNT_dec(MUTABLE_SV(revmeta->mro_linear_all)); - revmeta->mro_linear_all = NULL; - /* This is just acting as a shortcut pointer. */ - revmeta->mro_linear_current = NULL; - } else if (revmeta->mro_linear_current) { - /* Only the current MRO is stored, so this owns the data. */ - SvREFCNT_dec(revmeta->mro_linear_current); - revmeta->mro_linear_current = NULL; - } + CLEAR_LINEAR(revmeta); if(!is_universal) revmeta->cache_gen++; if(revmeta->mro_nextmethod) hv_clear(revmeta->mro_nextmethod); + if (!SvOBJECT(revstash)) SvSTASH(revstash) = NULL; + + (void) + hv_store( + isa_hashes, (const char*)&revstash, sizeof(HV *), + revmeta->isa ? (SV *)revmeta->isa : &PL_sv_undef, 0 + ); + revmeta->isa = NULL; + } + + /* Second pass: Update PL_isarev. We can just use isa_hashes to + * avoid another round of stash lookups. */ + + /* isarev might be deleted from PL_isarev during this loop, so hang + * on to it. */ + SvREFCNT_inc_simple_void_NN(sv_2mortal((SV *)isarev)); + + if(isa_hashes) { + hv_iterinit(isa_hashes); + while((iter = hv_iternext(isa_hashes))) { + HV* const revstash = *(HV **)HEK_KEY(HeKEY_hek(iter)); + HV * const isa = (HV *)HeVAL(iter); + const HEK *namehek; + + /* We're starting at the 2nd element, skipping revstash */ + linear_mro = mro_get_linear_isa(revstash); + svp = AvARRAY(linear_mro) + 1; + items = AvFILLp(linear_mro); + + namehek = HvENAME_HEK(revstash); + if (!namehek) namehek = HvNAME_HEK(revstash); + + while (items--) { + SV* const sv = *svp++; + HV* mroisarev; + + HE *he = hv_fetch_ent(PL_isarev, sv, TRUE, 0); + + /* That fetch should not fail. But if it had to create + a new SV for us, then will need to upgrade it to an + HV (which sv_upgrade() can now do for us). */ + + mroisarev = MUTABLE_HV(HeVAL(he)); + + SvUPGRADE(MUTABLE_SV(mroisarev), SVt_PVHV); + + /* This hash only ever contains PL_sv_yes. Storing it + over itself is almost as cheap as calling hv_exists, + so on aggregate we expect to save time by not making + two calls to the common HV code for the case where + it doesn't exist. */ + + (void) + hv_store( + mroisarev, HEK_KEY(namehek), + HEK_UTF8(namehek) ? -HEK_LEN(namehek) : HEK_LEN(namehek), + &PL_sv_yes, 0 + ); + } + + if((SV *)isa != &PL_sv_undef) + mro_clean_isarev( + isa, HEK_KEY(namehek), HEK_LEN(namehek), + HvMROMETA(revstash)->isa, (HEK_UTF8(namehek) ? SVf_UTF8 : 0) + ); + } } } - /* Now iterate our MRO (parents), and do a few things: - 1) instantiate with the "fake" flag if they don't exist - 2) flag them as universal if we are universal - 3) Add everything from our isarev to their isarev + /* Now iterate our MRO (parents), adding ourselves and everything from + our isarev to their isarev. */ /* We're starting at the 2nd element, skipping ourselves here */ @@ -531,16 +675,610 @@ Perl_mro_isa_changed_in(pTHX_ HV* stash) save time by not making two calls to the common HV code for the case where it doesn't exist. */ - (void)hv_store(mroisarev, stashname, stashname_len, &PL_sv_yes, 0); - - if(isarev) { - hv_iterinit(isarev); - while((iter = hv_iternext(isarev))) { - I32 revkeylen; - char* const revkey = hv_iterkey(iter, &revkeylen); - (void)hv_store(mroisarev, revkey, revkeylen, &PL_sv_yes, 0); + (void)hv_store(mroisarev, stashname, + stashname_utf8 ? -(I32)stashname_len : (I32)stashname_len, &PL_sv_yes, 0); + } + + /* Delete our name from our former parents' isarevs. */ + if(isa && HvARRAY(isa)) + mro_clean_isarev(isa, stashname, stashname_len, meta->isa, + (stashname_utf8 ? SVf_UTF8 : 0) ); +} + +/* Deletes name from all the isarev entries listed in isa */ +STATIC void +S_mro_clean_isarev(pTHX_ HV * const isa, const char * const name, + const STRLEN len, HV * const exceptions, U32 flags) +{ + HE* iter; + + PERL_ARGS_ASSERT_MRO_CLEAN_ISAREV; + + /* Delete our name from our former parents' isarevs. */ + if(isa && HvARRAY(isa) && hv_iterinit(isa)) { + SV **svp; + while((iter = hv_iternext(isa))) { + I32 klen; + const char * const key = hv_iterkey(iter, &klen); + if(exceptions && hv_exists(exceptions, key, HeKUTF8(iter) ? -klen : klen)) + continue; + svp = hv_fetch(PL_isarev, key, HeKUTF8(iter) ? -klen : klen, 0); + if(svp) { + HV * const isarev = (HV *)*svp; + (void)hv_delete(isarev, name, (flags & SVf_UTF8) ? -(I32)len : (I32)len, G_DISCARD); + if(!HvARRAY(isarev) || !HvUSEDKEYS(isarev)) + (void)hv_delete(PL_isarev, key, + HeKUTF8(iter) ? -klen : klen, G_DISCARD); + } + } + } +} + +/* +=for apidoc mro_package_moved + +Call this function to signal to a stash that it has been assigned to +another spot in the stash hierarchy. C is the stash that has been +assigned. C is the stash it replaces, if any. C is the glob +that is actually being assigned to. + +This can also be called with a null first argument to +indicate that C has been deleted. + +This function invalidates isa caches on the old stash, on all subpackages +nested inside it, and on the subclasses of all those, including +non-existent packages that have corresponding entries in C. + +It also sets the effective names (C) on all the stashes as +appropriate. + +If the C is present and is not in the symbol table, then this function +simply returns. This checked will be skipped if C. + +=cut +*/ +void +Perl_mro_package_moved(pTHX_ HV * const stash, HV * const oldstash, + const GV * const gv, U32 flags) +{ + SV *namesv; + HEK **namep; + I32 name_count; + HV *stashes; + HE* iter; + + PERL_ARGS_ASSERT_MRO_PACKAGE_MOVED; + assert(stash || oldstash); + + /* Determine the name(s) of the location that stash was assigned to + * or from which oldstash was removed. + * + * We cannot reliably use the name in oldstash, because it may have + * been deleted from the location in the symbol table that its name + * suggests, as in this case: + * + * $globref = \*foo::bar::; + * Symbol::delete_package("foo"); + * *$globref = \%baz::; + * *$globref = *frelp::; + * # calls mro_package_moved(%frelp::, %baz::, *$globref, NULL, 0) + * + * So we get it from the gv. But, since the gv may no longer be in the + * symbol table, we check that first. The only reliable way to tell is + * to see whether its stash has an effective name and whether the gv + * resides in that stash under its name. That effective name may be + * different from what gv_fullname4 would use. + * If flags & 1, the caller has asked us to skip the check. + */ + if(!(flags & 1)) { + SV **svp; + if( + !GvSTASH(gv) || !HvENAME(GvSTASH(gv)) || + !(svp = hv_fetch(GvSTASH(gv), GvNAME(gv), + GvNAMEUTF8(gv) ? -GvNAMELEN(gv) : GvNAMELEN(gv), 0)) || + *svp != (SV *)gv + ) return; + } + assert(SvOOK(GvSTASH(gv))); + assert(GvNAMELEN(gv)); + assert(GvNAME(gv)[GvNAMELEN(gv) - 1] == ':'); + assert(GvNAMELEN(gv) == 1 || GvNAME(gv)[GvNAMELEN(gv) - 2] == ':'); + name_count = HvAUX(GvSTASH(gv))->xhv_name_count; + if (!name_count) { + name_count = 1; + namep = &HvAUX(GvSTASH(gv))->xhv_name_u.xhvnameu_name; + } + else { + namep = HvAUX(GvSTASH(gv))->xhv_name_u.xhvnameu_names; + if (name_count < 0) ++namep, name_count = -name_count - 1; + } + if (name_count == 1) { + if (HEK_LEN(*namep) == 4 && strnEQ(HEK_KEY(*namep), "main", 4)) { + namesv = GvNAMELEN(gv) == 1 + ? newSVpvs_flags(":", SVs_TEMP) + : newSVpvs_flags("", SVs_TEMP); + } + else { + namesv = sv_2mortal(newSVhek(*namep)); + if (GvNAMELEN(gv) == 1) sv_catpvs(namesv, ":"); + else sv_catpvs(namesv, "::"); + } + if (GvNAMELEN(gv) != 1) { + sv_catpvn_flags( + namesv, GvNAME(gv), GvNAMELEN(gv) - 2, + /* skip trailing :: */ + GvNAMEUTF8(gv) ? SV_CATUTF8 : SV_CATBYTES + ); + } + } + else { + SV *aname; + namesv = sv_2mortal((SV *)newAV()); + while (name_count--) { + if(HEK_LEN(*namep) == 4 && strnEQ(HEK_KEY(*namep), "main", 4)){ + aname = GvNAMELEN(gv) == 1 + ? newSVpvs(":") + : newSVpvs(""); + namep++; + } + else { + aname = newSVhek(*namep++); + if (GvNAMELEN(gv) == 1) sv_catpvs(aname, ":"); + else sv_catpvs(aname, "::"); + } + if (GvNAMELEN(gv) != 1) { + sv_catpvn_flags( + aname, GvNAME(gv), GvNAMELEN(gv) - 2, + /* skip trailing :: */ + GvNAMEUTF8(gv) ? SV_CATUTF8 : SV_CATBYTES + ); } + av_push((AV *)namesv, aname); + } + } + + /* Get a list of all the affected classes. */ + /* We cannot simply pass them all to mro_isa_changed_in to avoid + the list, as that function assumes that only one package has + changed. It does not work with: + + @foo::ISA = qw( B B::B ); + *B:: = delete $::{"A::"}; + + as neither B nor B::B can be updated before the other, since they + will reset caches on foo, which will see either B or B::B with the + wrong name. The names must be set on *all* affected stashes before + we do anything else. (And linearisations must be cleared, too.) + */ + stashes = (HV *) sv_2mortal((SV *)newHV()); + mro_gather_and_rename( + stashes, (HV *) sv_2mortal((SV *)newHV()), + stash, oldstash, namesv + ); + + /* Once the caches have been wiped on all the classes, call + mro_isa_changed_in on each. */ + hv_iterinit(stashes); + while((iter = hv_iternext(stashes))) { + HV * const stash = *(HV **)HEK_KEY(HeKEY_hek(iter)); + if(HvENAME(stash)) { + /* We have to restore the original meta->isa (that + mro_gather_and_rename set aside for us) this way, in case + one class in this list is a superclass of a another class + that we have already encountered. In such a case, meta->isa + will have been overwritten without old entries being deleted + from PL_isarev. */ + struct mro_meta * const meta = HvMROMETA(stash); + if(meta->isa != (HV *)HeVAL(iter)){ + SvREFCNT_dec(meta->isa); + meta->isa + = HeVAL(iter) == &PL_sv_yes + ? NULL + : (HV *)HeVAL(iter); + HeVAL(iter) = NULL; /* We donated our reference count. */ + } + mro_isa_changed_in(stash); + } + } +} + +STATIC void +S_mro_gather_and_rename(pTHX_ HV * const stashes, HV * const seen_stashes, + HV *stash, HV *oldstash, SV *namesv) +{ + XPVHV* xhv; + HE *entry; + I32 riter = -1; + I32 items = 0; + const bool stash_had_name = stash && HvENAME(stash); + bool fetched_isarev = FALSE; + HV *seen = NULL; + HV *isarev = NULL; + SV **svp = NULL; + + PERL_ARGS_ASSERT_MRO_GATHER_AND_RENAME; + + /* We use the seen_stashes hash to keep track of which packages have + been encountered so far. This must be separate from the main list of + stashes, as we need to distinguish between stashes being assigned + and stashes being replaced/deleted. (A nested stash can be on both + sides of an assignment. We cannot simply skip iterating through a + stash on the right if we have seen it on the left, as it will not + get its ename assigned to it.) + + To avoid allocating extra SVs, instead of a bitfield we can make + bizarre use of immortals: + + &PL_sv_undef: seen on the left (oldstash) + &PL_sv_no : seen on the right (stash) + &PL_sv_yes : seen on both sides + + */ + + if(oldstash) { + /* Add to the big list. */ + struct mro_meta * meta; + HE * const entry + = (HE *) + hv_common( + seen_stashes, NULL, (const char *)&oldstash, sizeof(HV *), 0, + HV_FETCH_LVALUE|HV_FETCH_EMPTY_HE, NULL, 0 + ); + if(HeVAL(entry) == &PL_sv_undef || HeVAL(entry) == &PL_sv_yes) { + oldstash = NULL; + goto check_stash; + } + HeVAL(entry) + = HeVAL(entry) == &PL_sv_no ? &PL_sv_yes : &PL_sv_undef; + meta = HvMROMETA(oldstash); + (void) + hv_store( + stashes, (const char *)&oldstash, sizeof(HV *), + meta->isa + ? SvREFCNT_inc_simple_NN((SV *)meta->isa) + : &PL_sv_yes, + 0 + ); + CLEAR_LINEAR(meta); + + /* Update the effective name. */ + if(HvENAME_get(oldstash)) { + const HEK * const enamehek = HvENAME_HEK(oldstash); + if(SvTYPE(namesv) == SVt_PVAV) { + items = AvFILLp((AV *)namesv) + 1; + svp = AvARRAY((AV *)namesv); + } + else { + items = 1; + svp = &namesv; + } + while (items--) { + const U32 name_utf8 = SvUTF8(*svp); + STRLEN len; + const char *name = SvPVx_const(*svp, len); + if(PL_stashcache) { + DEBUG_o(Perl_deb(aTHX_ "mro_gather_and_rename clearing PL_stashcache for '%"SVf"'\n", + *svp)); + (void)hv_delete(PL_stashcache, name, name_utf8 ? -(I32)len : (I32)len, G_DISCARD); + } + ++svp; + hv_ename_delete(oldstash, name, len, name_utf8); + + if (!fetched_isarev) { + /* If the name deletion caused a name change, then we + * are not going to call mro_isa_changed_in with this + * name (and not at all if it has become anonymous) so + * we need to delete old isarev entries here, both + * those in the superclasses and this class's own list + * of subclasses. We simply delete the latter from + * PL_isarev, since we still need it. hv_delete morti- + * fies it for us, so sv_2mortal is not necessary. */ + if(HvENAME_HEK(oldstash) != enamehek) { + if(meta->isa && HvARRAY(meta->isa)) + mro_clean_isarev(meta->isa, name, len, 0, name_utf8); + isarev = (HV *)hv_delete(PL_isarev, name, + name_utf8 ? -(I32)len : (I32)len, 0); + fetched_isarev=TRUE; + } + } + } + } + } + check_stash: + if(stash) { + if(SvTYPE(namesv) == SVt_PVAV) { + items = AvFILLp((AV *)namesv) + 1; + svp = AvARRAY((AV *)namesv); + } + else { + items = 1; + svp = &namesv; + } + while (items--) { + const U32 name_utf8 = SvUTF8(*svp); + STRLEN len; + const char *name = SvPVx_const(*svp++, len); + hv_ename_add(stash, name, len, name_utf8); + } + + /* Add it to the big list if it needs + * mro_isa_changed_in called on it. That happens if it was + * detached from the symbol table (so it had no HvENAME) before + * being assigned to the spot named by the 'name' variable, because + * its cached isa linearisation is now stale (the effective name + * having changed), and subclasses will then use that cache when + * mro_package_moved calls mro_isa_changed_in. (See + * [perl #77358].) + * + * If it did have a name, then its previous name is still + * used in isa caches, and there is no need for + * mro_package_moved to call mro_isa_changed_in. + */ + + entry + = (HE *) + hv_common( + seen_stashes, NULL, (const char *)&stash, sizeof(HV *), 0, + HV_FETCH_LVALUE|HV_FETCH_EMPTY_HE, NULL, 0 + ); + if(HeVAL(entry) == &PL_sv_yes || HeVAL(entry) == &PL_sv_no) + stash = NULL; + else { + HeVAL(entry) + = HeVAL(entry) == &PL_sv_undef ? &PL_sv_yes : &PL_sv_no; + if(!stash_had_name) + { + struct mro_meta * const meta = HvMROMETA(stash); + (void) + hv_store( + stashes, (const char *)&stash, sizeof(HV *), + meta->isa + ? SvREFCNT_inc_simple_NN((SV *)meta->isa) + : &PL_sv_yes, + 0 + ); + CLEAR_LINEAR(meta); + } + } + } + + if(!stash && !oldstash) + /* Both stashes have been encountered already. */ + return; + + /* Add all the subclasses to the big list. */ + if(!fetched_isarev) { + /* If oldstash is not null, then we can use its HvENAME to look up + the isarev hash, since all its subclasses will be listed there. + It will always have an HvENAME. It the HvENAME was removed + above, then fetch_isarev will be true, and this code will not be + reached. + + If oldstash is null, then this is an empty spot with no stash in + it, so subclasses could be listed in isarev hashes belonging to + any of the names, so we have to check all of them. + */ + assert(!oldstash || HvENAME(oldstash)); + if (oldstash) { + /* Extra variable to avoid a compiler warning */ + char * const hvename = HvENAME(oldstash); + fetched_isarev = TRUE; + svp = hv_fetch(PL_isarev, hvename, + HvENAMEUTF8(oldstash) + ? -HvENAMELEN_get(oldstash) + : HvENAMELEN_get(oldstash), 0); + if (svp) isarev = MUTABLE_HV(*svp); + } + else if(SvTYPE(namesv) == SVt_PVAV) { + items = AvFILLp((AV *)namesv) + 1; + svp = AvARRAY((AV *)namesv); + } + else { + items = 1; + svp = &namesv; + } + } + if( + isarev || !fetched_isarev + ) { + while (fetched_isarev || items--) { + HE *iter; + + if (!fetched_isarev) { + HE * const he = hv_fetch_ent(PL_isarev, *svp++, 0, 0); + if (!he || !(isarev = MUTABLE_HV(HeVAL(he)))) continue; + } + + hv_iterinit(isarev); + while((iter = hv_iternext(isarev))) { + HV* revstash = gv_stashsv(hv_iterkeysv(iter), 0); + struct mro_meta * meta; + + if(!revstash) continue; + meta = HvMROMETA(revstash); + (void) + hv_store( + stashes, (const char *)&revstash, sizeof(HV *), + meta->isa + ? SvREFCNT_inc_simple_NN((SV *)meta->isa) + : &PL_sv_yes, + 0 + ); + CLEAR_LINEAR(meta); } + + if (fetched_isarev) break; + } + } + + /* This is partly based on code in hv_iternext_flags. We are not call- + ing that here, as we want to avoid resetting the hash iterator. */ + + /* Skip the entire loop if the hash is empty. */ + if(oldstash && HvUSEDKEYS(oldstash)) { + xhv = (XPVHV*)SvANY(oldstash); + seen = (HV *) sv_2mortal((SV *)newHV()); + + /* Iterate through entries in the oldstash, adding them to the + list, meanwhile doing the equivalent of $seen{$key} = 1. + */ + + while (++riter <= (I32)xhv->xhv_max) { + entry = (HvARRAY(oldstash))[riter]; + + /* Iterate through the entries in this list */ + for(; entry; entry = HeNEXT(entry)) { + const char* key; + I32 len; + + /* If this entry is not a glob, ignore it. + Try the next. */ + if (!isGV(HeVAL(entry))) continue; + + key = hv_iterkey(entry, &len); + if ((len > 1 && key[len-2] == ':' && key[len-1] == ':') + || (len == 1 && key[0] == ':')) { + HV * const oldsubstash = GvHV(HeVAL(entry)); + SV ** const stashentry + = stash ? hv_fetch(stash, key, HeUTF8(entry) ? -(I32)len : (I32)len, 0) : NULL; + HV *substash = NULL; + + /* Avoid main::main::main::... */ + if(oldsubstash == oldstash) continue; + + if( + ( + stashentry && *stashentry + && (substash = GvHV(*stashentry)) + ) + || (oldsubstash && HvENAME_get(oldsubstash)) + ) + { + /* Add :: and the key (minus the trailing ::) + to each name. */ + SV *subname; + if(SvTYPE(namesv) == SVt_PVAV) { + SV *aname; + items = AvFILLp((AV *)namesv) + 1; + svp = AvARRAY((AV *)namesv); + subname = sv_2mortal((SV *)newAV()); + while (items--) { + aname = newSVsv(*svp++); + if (len == 1) + sv_catpvs(aname, ":"); + else { + sv_catpvs(aname, "::"); + sv_catpvn_flags( + aname, key, len-2, + HeUTF8(entry) + ? SV_CATUTF8 : SV_CATBYTES + ); + } + av_push((AV *)subname, aname); + } + } + else { + subname = sv_2mortal(newSVsv(namesv)); + if (len == 1) sv_catpvs(subname, ":"); + else { + sv_catpvs(subname, "::"); + sv_catpvn_flags( + subname, key, len-2, + HeUTF8(entry) ? SV_CATUTF8 : SV_CATBYTES + ); + } + } + mro_gather_and_rename( + stashes, seen_stashes, + substash, oldsubstash, subname + ); + } + + (void)hv_store(seen, key, HeUTF8(entry) ? -(I32)len : (I32)len, &PL_sv_yes, 0); + } + } + } + } + + /* Skip the entire loop if the hash is empty. */ + if (stash && HvUSEDKEYS(stash)) { + xhv = (XPVHV*)SvANY(stash); + riter = -1; + + /* Iterate through the new stash, skipping $seen{$key} items, + calling mro_gather_and_rename(stashes,seen,entry,NULL, ...). */ + while (++riter <= (I32)xhv->xhv_max) { + entry = (HvARRAY(stash))[riter]; + + /* Iterate through the entries in this list */ + for(; entry; entry = HeNEXT(entry)) { + const char* key; + I32 len; + + /* If this entry is not a glob, ignore it. + Try the next. */ + if (!isGV(HeVAL(entry))) continue; + + key = hv_iterkey(entry, &len); + if ((len > 1 && key[len-2] == ':' && key[len-1] == ':') + || (len == 1 && key[0] == ':')) { + HV *substash; + + /* If this entry was seen when we iterated through the + oldstash, skip it. */ + if(seen && hv_exists(seen, key, HeUTF8(entry) ? -(I32)len : (I32)len)) continue; + + /* We get here only if this stash has no corresponding + entry in the stash being replaced. */ + + substash = GvHV(HeVAL(entry)); + if(substash) { + SV *subname; + + /* Avoid checking main::main::main::... */ + if(substash == stash) continue; + + /* Add :: and the key (minus the trailing ::) + to each name. */ + if(SvTYPE(namesv) == SVt_PVAV) { + SV *aname; + items = AvFILLp((AV *)namesv) + 1; + svp = AvARRAY((AV *)namesv); + subname = sv_2mortal((SV *)newAV()); + while (items--) { + aname = newSVsv(*svp++); + if (len == 1) + sv_catpvs(aname, ":"); + else { + sv_catpvs(aname, "::"); + sv_catpvn_flags( + aname, key, len-2, + HeUTF8(entry) + ? SV_CATUTF8 : SV_CATBYTES + ); + } + av_push((AV *)subname, aname); + } + } + else { + subname = sv_2mortal(newSVsv(namesv)); + if (len == 1) sv_catpvs(subname, ":"); + else { + sv_catpvs(subname, "::"); + sv_catpvn_flags( + subname, key, len-2, + HeUTF8(entry) ? SV_CATUTF8 : SV_CATBYTES + ); + } + } + mro_gather_and_rename( + stashes, seen_stashes, + substash, NULL, subname + ); + } + } + } + } } } @@ -552,7 +1290,7 @@ of the given stash, so that they might notice the changes in this one. Ideally, all instances of C in -perl source outside of C should be +perl source outside of F should be replaced by calls to this. Perl automatically handles most of the common @@ -577,10 +1315,12 @@ via, C. void Perl_mro_method_changed_in(pTHX_ HV *stash) { - const char * const stashname = HvNAME_get(stash); - const STRLEN stashname_len = HvNAMELEN_get(stash); + const char * const stashname = HvENAME_get(stash); + const STRLEN stashname_len = HvENAMELEN_get(stash); + const bool stashname_utf8 = HvENAMEUTF8(stash) ? 1 : 0; - SV ** const svp = hv_fetch(PL_isarev, stashname, stashname_len, 0); + SV ** const svp = hv_fetch(PL_isarev, stashname, + stashname_utf8 ? -(I32)stashname_len : (I32)stashname_len, 0); HV * const isarev = svp ? MUTABLE_HV(*svp) : NULL; PERL_ARGS_ASSERT_MRO_METHOD_CHANGED_IN; @@ -591,6 +1331,9 @@ Perl_mro_method_changed_in(pTHX_ HV *stash) /* Inc the package generation, since a local method changed */ HvMROMETA(stash)->pkg_gen++; + /* DESTROY can be cached in SvSTASH. */ + if (!SvOBJECT(stash)) SvSTASH(stash) = NULL; + /* If stash is UNIVERSAL, or one of UNIVERSAL's parents, invalidate all method caches globally */ if((stashname_len == 9 && strEQ(stashname, "UNIVERSAL")) @@ -606,9 +1349,7 @@ Perl_mro_method_changed_in(pTHX_ HV *stash) hv_iterinit(isarev); while((iter = hv_iternext(isarev))) { - I32 len; - const char* const revkey = hv_iterkey(iter, &len); - HV* const revstash = gv_stashpvn(revkey, len, 0); + HV* const revstash = gv_stashsv(hv_iterkeysv(iter), 0); struct mro_meta* mrometa; if(!revstash) continue; @@ -616,8 +1357,13 @@ Perl_mro_method_changed_in(pTHX_ HV *stash) mrometa->cache_gen++; if(mrometa->mro_nextmethod) hv_clear(mrometa->mro_nextmethod); + if (!SvOBJECT(revstash)) SvSTASH(revstash) = NULL; } } + + /* The method change may be due to *{$package . "::()"} = \&nil; in + overload.pm. */ + HvAMAGIC_on(stash); } void @@ -687,8 +1433,8 @@ XS(XS_mro_method_changed_in) * Local variables: * c-indentation-style: bsd * c-basic-offset: 4 - * indent-tabs-mode: t + * indent-tabs-mode: nil * End: * - * ex: set ts=8 sts=4 sw=4 noet: + * ex: set ts=8 sts=4 sw=4 et: */