#include "EXTERN.h"

#include "perl.h"

#include "XSUB.h"

#ifndef PadARRAY

typedef AV PADNAMELIST;

typedef SV PADNAME;

# if PERL_VERSION < 8 || (PERL_VERSION == 8 && !PERL_SUBVERSION)

typedef AV PAD;

# endif

# define PadlistARRAY(pl)      ((PAD **)AvARRAY(pl))

# define PadlistNAMES(pl)      (*PadlistARRAY(pl))

# define PadnamelistARRAY(pnl) ((PADNAME **)AvARRAY(pnl))

# define PadnamelistMAX(pnl)   AvFILLp(pnl)

# define PadARRAY              AvARRAY

# define PadnamePV(pn)         (SvPOKp(pn) ? SvPVX(pn) : NULL)

#endif

/* cargo-culted from PadWalker */

MODULE = Devel::LexAlias                PACKAGE = Devel::LexAlias

void

_lexalias(SV* cv_ref, char *name, SV* new_rv)

  CODE:

{

    CV*          cv   = SvROK(cv_ref) ? (CV*) SvRV(cv_ref) : NULL;

    PADNAMELIST* padn = cv ? PadlistNAMES(CvPADLIST(cv)) : PL_comppad_name;

    PAD*         padv = cv ? PadlistARRAY(CvPADLIST(cv))[1] : PL_comppad;

    SV*          new_sv;

    I32          i;

    if (!SvROK(new_rv)) croak("ref is not a reference");

    new_sv = SvRV(new_rv);

    for (i = 0; i <= PadnamelistMAX(padn); ++i) {

        PADNAME* namesv = PadnamelistARRAY(padn)[i];

        char*    name_str;

        if (namesv && (name_str = PadnamePV(namesv))) {

            if (!strcmp(name, name_str)) {

                SvREFCNT_dec(PadARRAY(padv)[i]);

                PadARRAY(padv)[i] = new_sv;

                SvREFCNT_inc(new_sv);

                SvPADMY_on(new_sv);

            }

        }

    }

}