--- /dev/null
+/*
+----------------------------------------------------------------------------
+
+ Devel::MRO/mro_compat.h - Provides mro functions for XS modules
+
+ Copyright (c) 2008-2009, Goro Fuji (gfx) <gfuji(at)cpan.org>.
+
+ This program is free software; you can redistribute it and/or
+ modify it under the same terms as Perl itself.
+
+----------------------------------------------------------------------------
+
+Usage:
+ #include "mro_compat.h"
+
+Functions:
+ AV* mro_get_linear_isa(HV* stash)
+ UV mro_get_pkg_gen(HV* stash)
+ void mro_method_changed_in(HV* stash)
+
+
+ See "perldoc Devel::MRO" for details.
+ */
+
+
+#ifdef mro_get_linear_isa /* >= 5.10.0 */
+
+/* NOTE:
+ Because ActivePerl 5.10.0 does not provide Perl_mro_meta_init(),
+ which is used in HvMROMETA() macro, this mro_get_pkg_gen() refers
+ to xhv_mro_meta directly.
+*/
+/* compatible with &mro::get_pkg_gen() */
+#ifndef mro_get_pkg_gen
+#define mro_get_pkg_gen(stash) (HvAUX(stash) ? HvAUX(stash)->xhv_mro_meta->pkg_gen : (U32)0)
+#endif
+
+#ifndef mro_get_cache_gen
+#define mro_get_cache_gen(stash) (HvAUX(stash) ? HvAUX(stash)->xhv_mro_meta->cache_gen : (U32)0)
+#endif
+
+#ifndef mro_get_gen
+#define mro_get_gen(stash) (HvAUX(stash) ? (HvAUX(stash)->xhv_mro_meta->pkg_gen + HvAUX(stash)->xhv_mro_meta->cache_gen) : (U32)0)
+#endif
+
+#else /* < 5.10.0 */
+#define mro_get_linear_isa(stash) my_mro_get_linear_isa(aTHX_ stash)
+
+#define mro_method_changed_in(stash) ((void)stash, (void)PL_sub_generation++)
+#define mro_get_pkg_gen(stash) ((void)stash, PL_sub_generation)
+#define mro_get_cache_gen(stash) ((void)stash, (U32)0)
+#define mro_get_gen(stash) ((void)stash, PL_sub_generation)
+
+
+#if defined(NEED_mro_get_linear_isa) && !defined(NEED_mro_get_linear_isa_GLOBAL)
+static AV* my_mro_get_linear_isa(pTHX_ HV* const stash);
+static
+#else
+extern AV* my_mro_get_linear_isa(pTHX_ HV* const stash);
+#endif /* !NEED_mro_get_linear_isa */
+
+#if defined(NEED_mro_get_linear_isa) || defined(NEED_mro_get_linear_isa_GLOBAL)
+#define ISA_CACHE "::LINEALIZED_ISA_CACHE::"
+
+/* call &mro::get_linear_isa, which is actually &MRO::Compat::__get_linear_isa */
+AV*
+my_mro_get_linear_isa(pTHX_ HV* const stash){
+ GV* cachegv;
+ AV* isa; /* linearized ISA cache */
+ SV* gen; /* package generation */
+ CV* get_linear_isa;
+
+ assert(stash != NULL);
+ assert(SvTYPE(stash) == SVt_PVHV);
+
+ cachegv = *(GV**)hv_fetchs(stash, ISA_CACHE, TRUE);
+ if(!isGV(cachegv))
+ gv_init(cachegv, stash, ISA_CACHE, sizeof(ISA_CACHE)-1, GV_ADD);
+
+ isa = GvAVn(cachegv);
+#ifdef GvSVn
+ gen = GvSVn(cachegv);
+#else
+ gen = GvSV(cachegv);
+#endif
+
+ if(SvIOK(gen) && SvIVX(gen) == (IV)mro_get_pkg_gen(stash)){
+ return isa; /* returns the cache if available */
+ }
+ else{
+ SvREADONLY_off(isa);
+ av_clear(isa);
+ }
+
+ get_linear_isa = get_cv("mro::get_linear_isa", FALSE);
+ if(!get_linear_isa){
+ ENTER;
+ SAVETMPS;
+
+ Perl_load_module(aTHX_ PERL_LOADMOD_NOIMPORT, newSVpvs("MRO::Compat"), NULL, NULL);
+ get_linear_isa = get_cv("mro::get_linear_isa", TRUE);
+
+ FREETMPS;
+ LEAVE;
+ }
+
+ {
+ SV* avref;
+ dSP;
+
+ ENTER;
+ SAVETMPS;
+
+ PUSHMARK(SP);
+ mXPUSHp(HvNAME(stash), strlen(HvNAME(stash)));
+ PUTBACK;
+
+ call_sv((SV*)get_linear_isa, G_SCALAR);
+
+ SPAGAIN;
+ avref = POPs;
+ PUTBACK;
+
+ if(SvROK(avref) && SvTYPE(SvRV(avref)) == SVt_PVAV){
+ AV* const av = (AV*)SvRV(avref);
+ I32 const len = AvFILLp(av) + 1;
+ I32 i;
+
+ for(i = 0; i < len; i++){
+ HV* const st = gv_stashsv(AvARRAY(av)[i], FALSE);
+ if(st)
+ av_push(isa, newSVpv(HvNAME(st), 0));
+ }
+ SvREADONLY_on(isa);
+ }
+ else{
+ Perl_croak(aTHX_ "panic: mro::get_linear_isa() didn't return an ARRAY reference");
+ }
+
+ FREETMPS;
+ LEAVE;
+ }
+
+ sv_setiv(gen, (IV)mro_get_pkg_gen(stash));
+ return isa;
+}
+#undef ISA_CACHE
+
+#endif /* !(defined(NEED_mro_get_linear_isa) || defined(NEED_mro_get_linear_isa_GLOBAL)) */
+
+#endif /* end of the file */