%module argv

// This tells SWIG to treat char ** as a special case
%typemap(in) char ** {
	AV *tempav;
	I32 len;
	int i;
	SV  **tv;
	if (!SvROK($input))
	    croak("Argument $argnum is not a reference.");
        if (SvTYPE(SvRV($input)) != SVt_PVAV)
	    croak("Argument $argnum is not an array.");
        tempav = (AV*)SvRV($input);
	len = av_len(tempav);
	$1 = (char **) malloc((len+2)*sizeof(char *));
	for (i = 0; i <= len; i++) {
	    tv = av_fetch(tempav, i, 0);	
	    $1[i] = (char *) SvPV(*tv,PL_na);
        }
	$1[i] = NULL;
};

// This cleans up the char ** array after the function call
%typemap(freearg) char ** {
	free($1);
}

// Creates a new Perl array and places a NULL-terminated char ** into it
%typemap(out) char ** {
	AV *myav;
	SV **svs;
	int i = 0,len = 0;
	/* Figure out how many elements we have */
	while ($1[len])
	   len++;
	svs = (SV **) malloc(len*sizeof(SV *));
	for (i = 0; i < len ; i++) {
	    svs[i] = sv_newmortal();
	    sv_setpv((SV*)svs[i],$1[i]);
	};
	myav =	av_make(len,svs);
	free(svs);
        $result = newRV((SV*)myav);
        sv_2mortal($result);
        argvi++;
}