X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=mro.c;h=fe776474d488c92c69f681f75e991c68a6ac9f74;hb=cd477a63b79827394e51e6698e1a59ee11fa4eeb;hp=81626adf1db978aec5c0497da8540b3ad5b47d5f;hpb=25270bc0b7409c7dbdeef1a6ec0b548e2d3e51a1;p=p5sagit%2Fp5-mst-13.2.git diff --git a/mro.c b/mro.c index 81626ad..fe77647 100644 --- a/mro.c +++ b/mro.c @@ -1,6 +1,7 @@ /* mro.c * * Copyright (c) 2007 Brandon L Black + * Copyright (c) 2007, 2008 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. @@ -8,8 +9,10 @@ */ /* - * "Which order shall we go in?" said Frodo. "Eldest first, or quickest first? - * You'll be last either way, Master Peregrin." + * 'Which order shall we go in?' said Frodo. 'Eldest first, or quickest first? + * You'll be last either way, Master Peregrin.' + * + * [p.101 of _The Lord of the Rings_, I/iii: "A Conspiracy Unmasked"] */ /* @@ -21,29 +24,125 @@ These functions are related to the method resolution order of perl classes */ #include "EXTERN.h" +#define PERL_IN_MRO_C #include "perl.h" +static const struct mro_alg dfs_alg = + {S_mro_get_linear_isa_dfs, "dfs", 3, 0, 0}; + +SV * +Perl_mro_get_private_data(pTHX_ struct mro_meta *const smeta, + const struct mro_alg *const which) +{ + SV **data; + PERL_ARGS_ASSERT_MRO_GET_PRIVATE_DATA; + + 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; + + /* If we've been asked to look up the private data for the current MRO, then + cache it. */ + if (smeta->mro_which == which) + smeta->mro_linear_current = *data; + + return *data; +} + +SV * +Perl_mro_set_private_data(pTHX_ struct mro_meta *const smeta, + const struct mro_alg *const which, SV *const data) +{ + PERL_ARGS_ASSERT_MRO_SET_PRIVATE_DATA; + + if (!smeta->mro_linear_all) { + if (smeta->mro_which == which) { + /* If all we need to store is the current MRO's data, then don't use + memory on a hash with 1 element - store it direct, and signal + this by leaving the would-be-hash NULL. */ + smeta->mro_linear_current = data; + return data; + } else { + HV *const hv = newHV(); + /* Start with 2 buckets. It's unlikely we'll need more. */ + HvMAX(hv) = 1; + smeta->mro_linear_all = hv; + + if (smeta->mro_linear_current) { + /* If we were storing something directly, put it in the hash + before we lose it. */ + Perl_mro_set_private_data(aTHX_ smeta, smeta->mro_which, + smeta->mro_linear_current); + } + } + } + + /* We get here if we're storing more than one linearisation for this stash, + or the linearisation we are storing is not that if its current MRO. */ + + if (smeta->mro_which == which) { + /* If we've been asked to store the private data for the current MRO, + then cache it. */ + smeta->mro_linear_current = data; + } + + if (!Perl_hv_common(aTHX_ smeta->mro_linear_all, NULL, + which->name, which->length, which->kflags, + HV_FETCH_ISSTORE, data, which->hash)) { + Perl_croak(aTHX_ "panic: hv_store() failed in set_mro_private_data() " + "for '%.*s' %d", (int) which->length, which->name, + which->kflags); + } + + return data; +} + +const struct mro_alg * +Perl_mro_get_from_name(pTHX_ SV *name) { + SV **data; + + PERL_ARGS_ASSERT_MRO_GET_FROM_NAME; + + 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); + assert(SvIOK(*data)); + return INT2PTR(const struct mro_alg *, SvUVX(*data)); +} + +void +Perl_mro_register(pTHX_ const struct mro_alg *mro) { + SV *wrapper = newSVuv(PTR2UV(mro)); + + PERL_ARGS_ASSERT_MRO_REGISTER; + + + if (!Perl_hv_common(aTHX_ PL_registered_mros, NULL, + mro->name, mro->length, mro->kflags, + HV_FETCH_ISSTORE, wrapper, mro->hash)) { + SvREFCNT_dec(wrapper); + Perl_croak(aTHX_ "panic: hv_store() failed in mro_register() " + "for '%.*s' %d", (int) mro->length, mro->name, mro->kflags); + } +} + struct mro_meta* Perl_mro_meta_init(pTHX_ HV* stash) { struct mro_meta* newmeta; - assert(stash); + PERL_ARGS_ASSERT_MRO_META_INIT; assert(HvAUX(stash)); assert(!(HvAUX(stash)->xhv_mro_meta)); Newxz(newmeta, 1, struct mro_meta); HvAUX(stash)->xhv_mro_meta = newmeta; - newmeta->sub_generation = 1; - - /* Manually flag UNIVERSAL as being universal. - This happens early in perl booting (when universal.c - does the newXS calls for UNIVERSAL::*), and infects - other packages as they are added to UNIVERSAL's MRO - */ - if(HvNAMELEN_get(stash) == 9 - && strEQ(HEK_KEY(HvAUX(stash)->xhv_name), "UNIVERSAL")) { - HvMROMETA(stash)->is_universal = 1; - } + newmeta->cache_gen = 1; + newmeta->pkg_gen = 1; + newmeta->mro_which = &dfs_alg; return newmeta; } @@ -56,23 +155,30 @@ Perl_mro_meta_dup(pTHX_ struct mro_meta* smeta, CLONE_PARAMS* param) { struct mro_meta* newmeta; - assert(smeta); + PERL_ARGS_ASSERT_MRO_META_DUP; Newx(newmeta, 1, struct mro_meta); Copy(smeta, newmeta, 1, struct mro_meta); - if (newmeta->mro_linear_dfs) - newmeta->mro_linear_dfs - = (AV*) SvREFCNT_inc(sv_dup((SV*)newmeta->mro_linear_dfs, param)); - if (newmeta->mro_linear_c3) - newmeta->mro_linear_c3 - = (AV*) SvREFCNT_inc(sv_dup((SV*)newmeta->mro_linear_c3, param)); - if (newmeta->mro_isarev) - newmeta->mro_isarev - = (HV*) SvREFCNT_inc(sv_dup((SV*)newmeta->mro_isarev, param)); + if (newmeta->mro_linear_all) { + newmeta->mro_linear_all + = MUTABLE_HV(SvREFCNT_inc(sv_dup((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)); + } + if (newmeta->mro_nextmethod) newmeta->mro_nextmethod - = (HV*) SvREFCNT_inc(sv_dup((SV*)newmeta->mro_nextmethod, param)); + = MUTABLE_HV(SvREFCNT_inc(sv_dup((const SV *)newmeta->mro_nextmethod, param))); + if (newmeta->isa) + newmeta->isa + = MUTABLE_HV(SvREFCNT_inc(sv_dup((const SV *)newmeta->isa, param))); return newmeta; } @@ -95,52 +201,58 @@ invalidated). =cut */ -AV* -Perl_mro_get_linear_isa_dfs(pTHX_ HV *stash, I32 level) +static AV* +S_mro_get_linear_isa_dfs(pTHX_ HV *stash, U32 level) { AV* retval; GV** gvp; GV* gv; AV* av; - const char* stashname; + const HEK* stashhek; struct mro_meta* meta; + SV *our_name; + HV *stored; - assert(stash); + PERL_ARGS_ASSERT_MRO_GET_LINEAR_ISA_DFS; assert(HvAUX(stash)); - stashname = HvNAME_get(stash); - if (!stashname) - Perl_croak(aTHX_ - "Can't linearize anonymous symbol table"); + stashhek = 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'", - stashname); + HEK_KEY(stashhek)); meta = HvMROMETA(stash); /* return cache if valid */ - if((retval = meta->mro_linear_dfs)) { + if((retval = MUTABLE_AV(MRO_GET_PRIVATE_DATA(meta, &dfs_alg)))) { return retval; } /* not in cache, make a new one */ - retval = newAV(); - av_push(retval, newSVpv(stashname, 0)); /* add ourselves at the top */ + retval = MUTABLE_AV(sv_2mortal(MUTABLE_SV(newAV()))); + /* We use this later in this function, but don't need a reference to it + beyond the end of this function, so reference count is fine. */ + our_name = newSVhek(stashhek); + av_push(retval, our_name); /* add ourselves at the top */ /* fetch our @ISA */ gvp = (GV**)hv_fetchs(stash, "ISA", FALSE); av = (gvp && (gv = *gvp) && isGV_with_GP(gv)) ? GvAV(gv) : NULL; - if(av && AvFILLp(av) >= 0) { + /* "stored" is used to keep track of all of the classnames we have added to + the MRO so far, so we can do a quick exists check and avoid adding + duplicate classnames to the MRO as we go. + It's then retained to be re-used as a fast lookup for ->isa(), by adding + our own name and "UNIVERSAL" to it. */ - /* "stored" is used to keep track of all of the classnames - we have added to the MRO so far, so we can do a quick - exists check and avoid adding duplicate classnames to - the MRO as we go. */ + stored = MUTABLE_HV(sv_2mortal(MUTABLE_SV(newHV()))); + + if(av && AvFILLp(av) >= 0) { - HV* stored = (HV*)sv_2mortal((SV*)newHV()); SV **svp = AvARRAY(av); I32 items = AvFILLp(av) + 1; @@ -159,7 +271,10 @@ Perl_mro_get_linear_isa_dfs(pTHX_ HV *stash, I32 level) } else { /* otherwise, recurse into ourselves for the MRO - of this @ISA member, and append their MRO to ours */ + of this @ISA member, and append their MRO to ours. + The recursive call could throw an exception, which + has memory management implications here, hence the use of + the mortal. */ const AV *const subrv = mro_get_linear_isa_dfs(basestash, level + 1); @@ -168,182 +283,58 @@ Perl_mro_get_linear_isa_dfs(pTHX_ HV *stash, I32 level) } while(subrv_items--) { SV *const subsv = *subrv_p++; - if(!hv_exists_ent(stored, subsv, 0)) { - hv_store_ent(stored, subsv, &PL_sv_undef, 0); - av_push(retval, newSVsv(subsv)); + /* 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); } } } } - /* we don't want anyone modifying the cache entry but us, - and we do so by replacing it completely */ - SvREADONLY_on(retval); - - meta->mro_linear_dfs = retval; - return retval; -} - -/* -=for apidoc mro_get_linear_isa_c3 + (void) hv_store_ent(stored, our_name, &PL_sv_undef, 0); + (void) hv_store(stored, "UNIVERSAL", 9, &PL_sv_undef, 0); -Returns the C3 linearization of @ISA -the given stash. The return value is a read-only AV*. -C should be 0 (it is used internally in this -function's recursion). + SvREFCNT_inc_simple_void_NN(stored); + SvTEMP_off(stored); + SvREADONLY_on(stored); -You are responsible for C on the -return value if you plan to store it anywhere -semi-permanently (otherwise it might be deleted -out from under you the next time the cache is -invalidated). + meta->isa = stored; -=cut -*/ - -AV* -Perl_mro_get_linear_isa_c3(pTHX_ HV* stash, I32 level) -{ - AV* retval; - GV** gvp; - GV* gv; - AV* isa; - const char* stashname; - STRLEN stashname_len; - struct mro_meta* meta; - - assert(stash); - assert(HvAUX(stash)); - - stashname = HvNAME_get(stash); - stashname_len = HvNAMELEN_get(stash); - if (!stashname) - Perl_croak(aTHX_ - "Can't linearize anonymous symbol table"); - - if (level > 100) - Perl_croak(aTHX_ "Recursive inheritance detected in package '%s'", - stashname); - - meta = HvMROMETA(stash); - - /* return cache if valid */ - if((retval = meta->mro_linear_c3)) { - return retval; - } - - /* not in cache, make a new one */ - - retval = newAV(); - av_push(retval, newSVpvn(stashname, stashname_len)); /* us first */ - - gvp = (GV**)hv_fetchs(stash, "ISA", FALSE); - isa = (gvp && (gv = *gvp) && isGV_with_GP(gv)) ? GvAV(gv) : NULL; - - /* For a better idea how the rest of this works, see the much clearer - pure perl version in Algorithm::C3 0.01: - http://search.cpan.org/src/STEVAN/Algorithm-C3-0.01/lib/Algorithm/C3.pm - (later versions go about it differently than this code for speed reasons) - */ - if(isa && AvFILLp(isa) >= 0) { - SV** seqs_ptr; - I32 seqs_items; - HV* tails = (HV*)sv_2mortal((SV*)newHV()); - AV* seqs = (AV*)sv_2mortal((SV*)newAV()); - I32 items = AvFILLp(isa) + 1; - SV** isa_ptr = AvARRAY(isa); - while(items--) { - AV* isa_lin; - SV* isa_item = *isa_ptr++; - HV* isa_item_stash = gv_stashsv(isa_item, 0); - if(!isa_item_stash) { - isa_lin = newAV(); - av_push(isa_lin, newSVsv(isa_item)); - } - else { - isa_lin = mro_get_linear_isa_c3(isa_item_stash, level + 1); /* recursion */ - } - av_push(seqs, (SV*)av_make(AvFILLp(isa_lin)+1, AvARRAY(isa_lin))); - } - av_push(seqs, (SV*)av_make(AvFILLp(isa)+1, AvARRAY(isa))); - - seqs_ptr = AvARRAY(seqs); - seqs_items = AvFILLp(seqs) + 1; - while(seqs_items--) { - AV* seq = (AV*)*seqs_ptr++; - I32 seq_items = AvFILLp(seq); - if(seq_items > 0) { - SV** seq_ptr = AvARRAY(seq) + 1; - while(seq_items--) { - SV* seqitem = *seq_ptr++; - HE* he = hv_fetch_ent(tails, seqitem, 0, 0); - if(!he) { - hv_store_ent(tails, seqitem, newSViv(1), 0); - } - else { - SV* val = HeVAL(he); - sv_inc(val); - } - } - } - } - - while(1) { - SV* seqhead = NULL; - SV* cand = NULL; - SV* winner = NULL; - SV* val; - HE* tail_entry; - AV* seq; - SV** avptr = AvARRAY(seqs); - items = AvFILLp(seqs)+1; - while(items--) { - SV** svp; - seq = (AV*)*avptr++; - if(AvFILLp(seq) < 0) continue; - svp = av_fetch(seq, 0, 0); - seqhead = *svp; - if(!winner) { - cand = seqhead; - if((tail_entry = hv_fetch_ent(tails, cand, 0, 0)) - && (val = HeVAL(tail_entry)) - && (SvIVX(val) > 0)) - continue; - winner = newSVsv(cand); - av_push(retval, winner); - } - if(!sv_cmp(seqhead, winner)) { - - /* this is basically shift(@seq) in void context */ - SvREFCNT_dec(*AvARRAY(seq)); - *AvARRAY(seq) = &PL_sv_undef; - AvARRAY(seq) = AvARRAY(seq) + 1; - AvMAX(seq)--; - AvFILLp(seq)--; - - if(AvFILLp(seq) < 0) continue; - svp = av_fetch(seq, 0, 0); - seqhead = *svp; - tail_entry = hv_fetch_ent(tails, seqhead, 0, 0); - val = HeVAL(tail_entry); - sv_dec(val); - } - } - if(!cand) break; - if(!winner) { - SvREFCNT_dec(retval); - Perl_croak(aTHX_ "Inconsistent hierarchy during C3 merge of class '%s': " - "merging failed on parent '%"SVf"'", stashname, SVfARG(cand)); - } - } - } + /* now that we're past the exception dangers, grab our own reference to + the AV we're about to use for the result. The reference owned by the + mortals' stack will be released soon, so everything will balance. */ + SvREFCNT_inc_simple_void_NN(retval); + SvTEMP_off(retval); /* we don't want anyone modifying the cache entry but us, and we do so by replacing it completely */ SvREADONLY_on(retval); - meta->mro_linear_c3 = retval; - return retval; + return MUTABLE_AV(Perl_mro_set_private_data(aTHX_ meta, &dfs_alg, + MUTABLE_SV(retval))); } /* @@ -367,17 +358,15 @@ AV* Perl_mro_get_linear_isa(pTHX_ HV *stash) { struct mro_meta* meta; - assert(stash); - assert(HvAUX(stash)); + + PERL_ARGS_ASSERT_MRO_GET_LINEAR_ISA; + if(!SvOOK(stash)) + Perl_croak(aTHX_ "Can't linearize anonymous symbol table"); meta = HvMROMETA(stash); - if(meta->mro_which == MRO_DFS) { - return mro_get_linear_isa_dfs(stash, 0); - } else if(meta->mro_which == MRO_C3) { - return mro_get_linear_isa_c3(stash, 0); - } else { + if (!meta->mro_which) Perl_croak(aTHX_ "panic: invalid MRO!"); - } + return meta->mro_which->resolve(aTHX_ stash, 0); } /* @@ -398,44 +387,80 @@ Perl_mro_isa_changed_in(pTHX_ HV* stash) HE* iter; SV** svp; I32 items; - struct mro_meta* meta; - char* stashname; + bool is_universal; + struct mro_meta * meta; + + const char * const stashname = HvNAME_get(stash); + const STRLEN stashname_len = HvNAMELEN_get(stash); + + PERL_ARGS_ASSERT_MRO_ISA_CHANGED_IN; - stashname = HvNAME_get(stash); + 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); - SvREFCNT_dec((SV*)meta->mro_linear_dfs); - SvREFCNT_dec((SV*)meta->mro_linear_c3); - meta->mro_linear_dfs = NULL; - meta->mro_linear_c3 = NULL; + 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; + } + if (meta->isa) { + SvREFCNT_dec(meta->isa); + meta->isa = NULL; + } + + /* Inc the package generation, since our @ISA changed */ + meta->pkg_gen++; /* Wipe the global method cache if this package is UNIVERSAL or one of its parents */ - if(meta->is_universal) - PL_sub_generation++; - /* Wipe the local method cache otherwise */ - else - meta->sub_generation++; + svp = hv_fetch(PL_isarev, stashname, stashname_len, 0); + isarev = svp ? MUTABLE_HV(*svp) : NULL; + + if((stashname_len == 9 && strEQ(stashname, "UNIVERSAL")) + || (isarev && hv_exists(isarev, "UNIVERSAL", 9))) { + PL_sub_generation++; + is_universal = TRUE; + } + else { /* Wipe the local method cache otherwise */ + meta->cache_gen++; + is_universal = FALSE; + } /* wipe next::method cache too */ if(meta->mro_nextmethod) hv_clear(meta->mro_nextmethod); - + /* Iterate the isarev (classes that are our children), wiping out their linearization and method caches */ - if((isarev = meta->mro_isarev)) { + if(isarev) { hv_iterinit(isarev); while((iter = hv_iternext(isarev))) { - SV* revkey = hv_iterkeysv(iter); - HV* revstash = gv_stashsv(revkey, 0); - struct mro_meta* revmeta = HvMROMETA(revstash); - SvREFCNT_dec((SV*)revmeta->mro_linear_dfs); - SvREFCNT_dec((SV*)revmeta->mro_linear_c3); - revmeta->mro_linear_dfs = NULL; - revmeta->mro_linear_c3 = NULL; - if(!meta->is_universal) - revmeta->sub_generation++; + I32 len; + const char* const revkey = hv_iterkey(iter, &len); + HV* revstash = gv_stashpvn(revkey, len, 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; + } + if(!is_universal) + revmeta->cache_gen++; if(revmeta->mro_nextmethod) hv_clear(revmeta->mro_nextmethod); } @@ -454,44 +479,31 @@ Perl_mro_isa_changed_in(pTHX_ HV* stash) while (items--) { SV* const sv = *svp++; - struct mro_meta* mrometa; HV* mroisarev; - HV* mrostash = gv_stashsv(sv, 0); - if(!mrostash) { - mrostash = gv_stashsv(sv, GV_ADD); - /* - We created the package on the fly, so - that we could store isarev information. - This flag lets gv_fetchmeth know about it, - so that it can still generate the very useful - "Can't locate package Foo for @Bar::ISA" warning. - */ - HvMROMETA(mrostash)->fake = 1; - } + HE *he = hv_fetch_ent(PL_isarev, sv, TRUE, 0); - mrometa = HvMROMETA(mrostash); - mroisarev = mrometa->mro_isarev; + /* 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. */ - /* is_universal is viral */ - if(meta->is_universal) - mrometa->is_universal = 1; + mroisarev = MUTABLE_HV(HeVAL(he)); - if(!mroisarev) - mroisarev = mrometa->mro_isarev = newHV(); + 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. */ - hv_store(mroisarev, stashname, strlen(stashname), &PL_sv_yes, 0); + (void)hv_store(mroisarev, stashname, stashname_len, &PL_sv_yes, 0); if(isarev) { hv_iterinit(isarev); while((iter = hv_iternext(isarev))) { - SV* revkey = hv_iterkeysv(iter); - hv_store_ent(mroisarev, revkey, &PL_sv_yes, 0); + I32 revkeylen; + char* const revkey = hv_iterkey(iter, &revkeylen); + (void)hv_store(mroisarev, revkey, revkeylen, &PL_sv_yes, 0); } } } @@ -500,487 +512,120 @@ Perl_mro_isa_changed_in(pTHX_ HV* stash) /* =for apidoc mro_method_changed_in -Like C, but invalidates method -caching on any child classes of the given stash, so -that they might notice the changes in this one. +Invalidates method caching on any child classes +of the given stash, so that they might notice +the changes in this one. Ideally, all instances of C in -the perl source should be replaced by calls to this. -Some already are, but some are more difficult to -replace. +perl source outside of C should be +replaced by calls to this. + +Perl automatically handles most of the common +ways a method might be redefined. However, there +are a few ways you could change a method in a stash +without the cache code noticing, in which case you +need to call this method afterwards: -Perl has always had problems with method caches -getting out of sync when one directly manipulates -stashes via things like C<%{Foo::} = %{Bar::}> or -C<${Foo::}{bar} = ...> or the equivalent. If -you do this in core or XS code, call this afterwards -on the destination stash to get things back in sync. +1) Directly manipulating the stash HV entries from +XS code. -If you're doing such a thing from pure perl, use -C, which -just calls this. +2) Assigning a reference to a readonly scalar +constant into a stash entry in order to create +a constant subroutine (like constant.pm +does). + +This same method is available from pure perl +via, C. =cut */ void Perl_mro_method_changed_in(pTHX_ HV *stash) { - struct mro_meta* meta = HvMROMETA(stash); - HV* isarev; - HE* iter; + const char * const stashname = HvNAME_get(stash); + const STRLEN stashname_len = HvNAMELEN_get(stash); + + SV ** const svp = hv_fetch(PL_isarev, stashname, stashname_len, 0); + HV * const isarev = svp ? MUTABLE_HV(*svp) : NULL; + + PERL_ARGS_ASSERT_MRO_METHOD_CHANGED_IN; + + if(!stashname) + Perl_croak(aTHX_ "Can't call mro_method_changed_in() on anonymous symbol table"); + + /* Inc the package generation, since a local method changed */ + HvMROMETA(stash)->pkg_gen++; /* If stash is UNIVERSAL, or one of UNIVERSAL's parents, invalidate all method caches globally */ - if(meta->is_universal) { + if((stashname_len == 9 && strEQ(stashname, "UNIVERSAL")) + || (isarev && hv_exists(isarev, "UNIVERSAL", 9))) { PL_sub_generation++; return; } /* else, invalidate the method caches of all child classes, but not itself */ - if((isarev = meta->mro_isarev)) { + if(isarev) { + HE* iter; + hv_iterinit(isarev); while((iter = hv_iternext(isarev))) { - SV* revkey = hv_iterkeysv(iter); - HV* revstash = gv_stashsv(revkey, 0); - struct mro_meta* mrometa = HvMROMETA(revstash); - mrometa->sub_generation++; + I32 len; + const char* const revkey = hv_iterkey(iter, &len); + HV* const revstash = gv_stashpvn(revkey, len, 0); + struct mro_meta* mrometa; + + if(!revstash) continue; + mrometa = HvMROMETA(revstash); + mrometa->cache_gen++; if(mrometa->mro_nextmethod) hv_clear(mrometa->mro_nextmethod); } } } -/* These two are static helpers for next::method and friends, - and re-implement a bunch of the code from pp_caller() in - a more efficient manner for this particular usage. -*/ - -STATIC I32 -__dopoptosub_at(const PERL_CONTEXT *cxstk, I32 startingblock) { - I32 i; - for (i = startingblock; i >= 0; i--) { - if(CxTYPE((PERL_CONTEXT*)(&cxstk[i])) == CXt_SUB) return i; - } - return i; -} - -STATIC SV* -__nextcan(pTHX_ SV* self, I32 throw_nomethod) -{ - register I32 cxix; - register const PERL_CONTEXT *ccstack = cxstack; - const PERL_SI *top_si = PL_curstackinfo; - HV* selfstash; - GV* cvgv; - SV *stashname; - const char *fq_subname; - const char *subname; - STRLEN fq_subname_len; - STRLEN stashname_len; - STRLEN subname_len; - SV* sv; - GV** gvp; - AV* linear_av; - SV** linear_svp; - SV* linear_sv; - HV* curstash; - GV* candidate = NULL; - CV* cand_cv = NULL; - const char *hvname; - I32 items; - struct mro_meta* selfmeta; - HV* nmcache; - HE* cache_entry; - - if(sv_isobject(self)) - selfstash = SvSTASH(SvRV(self)); - else - selfstash = gv_stashsv(self, 0); - - assert(selfstash); - - hvname = HvNAME_get(selfstash); - if (!hvname) - Perl_croak(aTHX_ "Can't use anonymous symbol table for method lookup"); - - cxix = __dopoptosub_at(cxstack, cxstack_ix); - - /* This block finds the contextually-enclosing fully-qualified subname, - much like looking at (caller($i))[3] until you find a real sub that - isn't ANON, etc */ - for (;;) { - /* we may be in a higher stacklevel, so dig down deeper */ - while (cxix < 0) { - if(top_si->si_type == PERLSI_MAIN) - Perl_croak(aTHX_ "next::method/next::can/maybe::next::method must be used in method context"); - top_si = top_si->si_prev; - ccstack = top_si->si_cxstack; - cxix = __dopoptosub_at(ccstack, top_si->si_cxix); - } - - if(CxTYPE((PERL_CONTEXT*)(&ccstack[cxix])) != CXt_SUB - || (PL_DBsub && GvCV(PL_DBsub) && ccstack[cxix].blk_sub.cv == GvCV(PL_DBsub))) { - cxix = __dopoptosub_at(ccstack, cxix - 1); - continue; - } - - { - const I32 dbcxix = __dopoptosub_at(ccstack, cxix - 1); - if (PL_DBsub && GvCV(PL_DBsub) && dbcxix >= 0 && ccstack[dbcxix].blk_sub.cv == GvCV(PL_DBsub)) { - if(CxTYPE((PERL_CONTEXT*)(&ccstack[dbcxix])) != CXt_SUB) { - cxix = dbcxix; - continue; - } - } - } - - cvgv = CvGV(ccstack[cxix].blk_sub.cv); - - if(!isGV(cvgv)) { - cxix = __dopoptosub_at(ccstack, cxix - 1); - continue; - } - - /* we found a real sub here */ - sv = sv_2mortal(newSV(0)); - - gv_efullname3(sv, cvgv, NULL); - - fq_subname = SvPVX(sv); - fq_subname_len = SvCUR(sv); - - subname = strrchr(fq_subname, ':'); - if(!subname) - Perl_croak(aTHX_ "next::method/next::can/maybe::next::method cannot find enclosing method"); - - subname++; - subname_len = fq_subname_len - (subname - fq_subname); - if(subname_len == 8 && strEQ(subname, "__ANON__")) { - cxix = __dopoptosub_at(ccstack, cxix - 1); - continue; - } - break; - } - - /* If we made it to here, we found our context */ - - /* Initialize the next::method cache for this stash - if necessary */ - selfmeta = HvMROMETA(selfstash); - if(!(nmcache = selfmeta->mro_nextmethod)) { - nmcache = selfmeta->mro_nextmethod = newHV(); - } - - /* Use the cached coderef if it exists */ - else if((cache_entry = hv_fetch_ent(nmcache, sv, 0, 0))) { - SV* val = HeVAL(cache_entry); - if(val == &PL_sv_undef) { - if(throw_nomethod) - Perl_croak(aTHX_ "No next::method '%s' found for %s", subname, hvname); - } - return val; - } - - /* beyond here is just for cache misses, so perf isn't as critical */ - - stashname_len = subname - fq_subname - 2; - stashname = sv_2mortal(newSVpvn(fq_subname, stashname_len)); - - linear_av = mro_get_linear_isa_c3(selfstash, 0); /* has ourselves at the top of the list */ - - linear_svp = AvARRAY(linear_av); - items = AvFILLp(linear_av) + 1; - - /* Walk down our MRO, skipping everything up - to the contextually enclosing class */ - while (items--) { - linear_sv = *linear_svp++; - assert(linear_sv); - if(sv_eq(linear_sv, stashname)) - break; - } - - /* Now search the remainder of the MRO for the - same method name as the contextually enclosing - method */ - if(items > 0) { - while (items--) { - linear_sv = *linear_svp++; - assert(linear_sv); - curstash = gv_stashsv(linear_sv, FALSE); - - if (!curstash || (HvMROMETA(curstash)->fake && !HvFILL(curstash))) { - if (ckWARN(WARN_SYNTAX)) - Perl_warner(aTHX_ packWARN(WARN_SYNTAX), "Can't locate package %"SVf" for @%s::ISA", - (void*)linear_sv, hvname); - continue; - } - - assert(curstash); - - gvp = (GV**)hv_fetch(curstash, subname, subname_len, 0); - if (!gvp) continue; - - candidate = *gvp; - assert(candidate); - - if (SvTYPE(candidate) != SVt_PVGV) - gv_init(candidate, curstash, subname, subname_len, TRUE); - - /* Notably, we only look for real entries, not method cache - entries, because in C3 the method cache of a parent is not - valid for the child */ - if (SvTYPE(candidate) == SVt_PVGV && (cand_cv = GvCV(candidate)) && !GvCVGEN(candidate)) { - SvREFCNT_inc_simple_void_NN((SV*)cand_cv); - hv_store_ent(nmcache, newSVsv(sv), (SV*)cand_cv, 0); - return (SV*)cand_cv; - } - } - } - - hv_store_ent(nmcache, newSVsv(sv), &PL_sv_undef, 0); - if(throw_nomethod) - Perl_croak(aTHX_ "No next::method '%s' found for %s", subname, hvname); - return &PL_sv_undef; -} - -#include "XSUB.h" - -XS(XS_mro_get_linear_isa); -XS(XS_mro_set_mro); -XS(XS_mro_get_mro); -XS(XS_mro_get_isarev); -XS(XS_mro_is_universal); -XS(XS_mro_get_global_sub_generation); -XS(XS_mro_invalidate_all_method_caches); -XS(XS_mro_get_sub_generation); -XS(XS_mro_method_changed_in); -XS(XS_next_can); -XS(XS_next_method); -XS(XS_maybe_next_method); - void -Perl_boot_core_mro(pTHX) -{ - dVAR; - static const char file[] = __FILE__; - - newXSproto("mro::get_linear_isa", XS_mro_get_linear_isa, file, "$;$"); - newXSproto("mro::set_mro", XS_mro_set_mro, file, "$$"); - newXSproto("mro::get_mro", XS_mro_get_mro, file, "$"); - newXSproto("mro::get_isarev", XS_mro_get_isarev, file, "$"); - newXSproto("mro::is_universal", XS_mro_is_universal, file, "$"); - newXSproto("mro::get_global_sub_generation", XS_mro_get_global_sub_generation, file, ""); - newXSproto("mro::invalidate_all_method_caches", XS_mro_invalidate_all_method_caches, file, ""); - newXSproto("mro::get_sub_generation", XS_mro_get_sub_generation, file, "$"); - newXSproto("mro::method_changed_in", XS_mro_method_changed_in, file, "$"); - newXS("next::can", XS_next_can, file); - newXS("next::method", XS_next_method, file); - newXS("maybe::next::method", XS_maybe_next_method, file); -} - -XS(XS_mro_get_linear_isa) { - dVAR; - dXSARGS; - AV* RETVAL; - HV* class_stash; - SV* classname; - - PERL_UNUSED_ARG(cv); - - if(items < 1 || items > 2) - Perl_croak(aTHX_ "Usage: mro::get_linear_isa(classname [, type ])"); - - classname = ST(0); - class_stash = gv_stashsv(classname, 0); - if(!class_stash) Perl_croak(aTHX_ "No such class: '%"SVf"'!", SVfARG(classname)); - - if(items > 1) { - char* which = SvPV_nolen(ST(1)); - if(strEQ(which, "dfs")) - RETVAL = mro_get_linear_isa_dfs(class_stash, 0); - else if(strEQ(which, "c3")) - RETVAL = mro_get_linear_isa_c3(class_stash, 0); - else - Perl_croak(aTHX_ "Invalid mro name: '%s'", which); - } - else { - RETVAL = mro_get_linear_isa(class_stash); - } - - ST(0) = newRV_inc((SV*)RETVAL); - sv_2mortal(ST(0)); - XSRETURN(1); -} - -XS(XS_mro_set_mro) +Perl_mro_set_mro(pTHX_ struct mro_meta *const meta, SV *const name) { - dVAR; - dXSARGS; - SV* classname; - char* whichstr; - mro_alg which; - HV* class_stash; - struct mro_meta* meta; - - PERL_UNUSED_ARG(cv); - - if (items != 2) - Perl_croak(aTHX_ "Usage: mro::set_mro(classname, type)"); + const struct mro_alg *const which = Perl_mro_get_from_name(aTHX_ name); + + PERL_ARGS_ASSERT_MRO_SET_MRO; - classname = ST(0); - whichstr = SvPV_nolen(ST(1)); - class_stash = gv_stashsv(classname, GV_ADD); - if(!class_stash) Perl_croak(aTHX_ "Cannot create class: '%"SVf"'!", SVfARG(classname)); - meta = HvMROMETA(class_stash); - - if(strEQ(whichstr, "dfs")) - which = MRO_DFS; - else if(strEQ(whichstr, "c3")) - which = MRO_C3; - else - Perl_croak(aTHX_ "Invalid mro name: '%s'", whichstr); + if (!which) + Perl_croak(aTHX_ "Invalid mro name: '%"SVf"'", name); if(meta->mro_which != which) { - meta->mro_which = which; + if (meta->mro_linear_current && !meta->mro_linear_all) { + /* If we were storing something directly, put it in the hash before + we lose it. */ + Perl_mro_set_private_data(aTHX_ meta, meta->mro_which, + MUTABLE_SV(meta->mro_linear_current)); + } + meta->mro_which = which; + /* Scrub our cached pointer to the private data. */ + meta->mro_linear_current = NULL; /* Only affects local method cache, not even child classes */ - meta->sub_generation++; + meta->cache_gen++; if(meta->mro_nextmethod) hv_clear(meta->mro_nextmethod); } - - XSRETURN_EMPTY; -} - - -XS(XS_mro_get_mro) -{ - dVAR; - dXSARGS; - SV* classname; - HV* class_stash; - struct mro_meta* meta; - - PERL_UNUSED_ARG(cv); - - if (items != 1) - Perl_croak(aTHX_ "Usage: mro::get_mro(classname)"); - - classname = ST(0); - class_stash = gv_stashsv(classname, 0); - if(!class_stash) Perl_croak(aTHX_ "No such class: '%"SVf"'!", SVfARG(classname)); - meta = HvMROMETA(class_stash); - - if(meta->mro_which == MRO_DFS) - ST(0) = sv_2mortal(newSVpvn("dfs", 3)); - else - ST(0) = sv_2mortal(newSVpvn("c3", 2)); - - XSRETURN(1); -} - -XS(XS_mro_get_isarev) -{ - dVAR; - dXSARGS; - SV* classname; - HV* class_stash; - HV* isarev; - - PERL_UNUSED_ARG(cv); - - if (items != 1) - Perl_croak(aTHX_ "Usage: mro::get_isarev(classname)"); - - classname = ST(0); - - class_stash = gv_stashsv(classname, 0); - if(!class_stash) Perl_croak(aTHX_ "No such class: '%"SVf"'!", SVfARG(classname)); - - SP -= items; - - if((isarev = HvMROMETA(class_stash)->mro_isarev)) { - HE* iter; - hv_iterinit(isarev); - while((iter = hv_iternext(isarev))) - XPUSHs(hv_iterkeysv(iter)); - } - - PUTBACK; - return; } -XS(XS_mro_is_universal) -{ - dVAR; - dXSARGS; - SV* classname; - HV* class_stash; - - PERL_UNUSED_ARG(cv); - - if (items != 1) - Perl_croak(aTHX_ "Usage: mro::get_mro(classname)"); - - classname = ST(0); - class_stash = gv_stashsv(classname, 0); - if(!class_stash) Perl_croak(aTHX_ "No such class: '%"SVf"'!", SVfARG(classname)); - - if (HvMROMETA(class_stash)->is_universal) - XSRETURN_YES; - else - XSRETURN_NO; -} - -XS(XS_mro_get_global_sub_generation) -{ - dVAR; - dXSARGS; - - PERL_UNUSED_ARG(cv); - - if (items != 0) - Perl_croak(aTHX_ "Usage: mro::get_global_sub_generation()"); - - ST(0) = sv_2mortal(newSViv(PL_sub_generation)); - XSRETURN(1); -} - -XS(XS_mro_invalidate_all_method_caches) -{ - dVAR; - dXSARGS; - - PERL_UNUSED_ARG(cv); - - if (items != 0) - Perl_croak(aTHX_ "Usage: mro::invalidate_all_method_caches()"); - - PL_sub_generation++; +#include "XSUB.h" - XSRETURN_EMPTY; -} +XS(XS_mro_method_changed_in); -XS(XS_mro_get_sub_generation) +void +Perl_boot_core_mro(pTHX) { dVAR; - dXSARGS; - SV* classname; - HV* class_stash; - - PERL_UNUSED_ARG(cv); - - if(items != 1) - Perl_croak(aTHX_ "Usage: mro::get_sub_generation(classname)"); + static const char file[] = __FILE__; - classname = ST(0); - class_stash = gv_stashsv(classname, 0); - if(!class_stash) Perl_croak(aTHX_ "No such class: '%"SVf"'!", SVfARG(classname)); + Perl_mro_register(aTHX_ &dfs_alg); - ST(0) = sv_2mortal(newSViv(HvMROMETA(class_stash)->sub_generation)); - XSRETURN(1); + newXSproto("mro::method_changed_in", XS_mro_method_changed_in, file, "$"); } XS(XS_mro_method_changed_in) @@ -990,10 +635,8 @@ XS(XS_mro_method_changed_in) SV* classname; HV* class_stash; - PERL_UNUSED_ARG(cv); - if(items != 1) - Perl_croak(aTHX_ "Usage: mro::method_changed_in(classname)"); + croak_xs_usage(cv, "classname"); classname = ST(0); @@ -1005,57 +648,6 @@ XS(XS_mro_method_changed_in) XSRETURN_EMPTY; } -XS(XS_next_can) -{ - dVAR; - dXSARGS; - SV* self = ST(0); - SV* methcv = __nextcan(aTHX_ self, 0); - - PERL_UNUSED_ARG(cv); - PERL_UNUSED_VAR(items); - - if(methcv == &PL_sv_undef) { - ST(0) = &PL_sv_undef; - } - else { - ST(0) = sv_2mortal(newRV_inc(methcv)); - } - - XSRETURN(1); -} - -XS(XS_next_method) -{ - dMARK; - dAX; - SV* self = ST(0); - SV* methcv = __nextcan(aTHX_ self, 1); - - PERL_UNUSED_ARG(cv); - - PL_markstack_ptr++; - call_sv(methcv, GIMME_V); -} - -XS(XS_maybe_next_method) -{ - dMARK; - dAX; - SV* self = ST(0); - SV* methcv = __nextcan(aTHX_ self, 0); - - PERL_UNUSED_ARG(cv); - - if(methcv == &PL_sv_undef) { - ST(0) = &PL_sv_undef; - XSRETURN(1); - } - - PL_markstack_ptr++; - call_sv(methcv, GIMME_V); -} - /* * Local variables: * c-indentation-style: bsd