#include "postgres.h"
 
#include "access/gist.h"
#include "access/itup.h"
#include "access/rtree.h"
#include "utils/elog.h"
#include "utils/palloc.h"
#include "utils/array.h"
#include "utils/builtins.h"
#include "storage/bufpage.h"

PG_FUNCTION_INFO_V1(level);
Datum level(PG_FUNCTION_ARGS); 

Datum level(PG_FUNCTION_ARGS)
{
	int nitems,ndim,*dim;
	char *p=0;
	ArrayType *intarray = (ArrayType *) DatumGetPointer(PG_GETARG_DATUM(0));
	if  (intarray == 0 ) return (int4) 0;
	intarray = DatumGetArrayTypeP(PointerGetDatum(intarray));
	if  (intarray == 0 ) return (int4) 0;
	p = ARR_DATA_PTR(intarray);
	if (p == 0) return (int4) 0;
	ndim = ARR_NDIM(intarray);
	dim = ARR_DIMS(intarray);
	nitems = ArrayGetNItems(ndim, dim);
	return (int4) nitems;
}