Is it posible? Either by using heap_form_tuple or BuildTupleFromCStrings.
CREATE TYPE p_type AS
(
x double precision,
y double precision
);
CREATE TYPE d_type AS
(
i p_type,
e p_type,
id integer
);
CREATE OR REPLACE FUNCTION demo()
RETURNS d_type
AS '/home/user/PostgreSQL/9.0/lib/mylib','demo'
LANGUAGE C STRICT;
Datum demo(PG_FUNCTION_ARGS) {
float8 xe = 3; float8 ye = 4;
bool isnull;
TupleDesc tupdesc; Datum values[3]; HeapTuple tuple;
if (get_call_result_type(fcinfo, NULL, &tupdesc) != TYPEFUNC_COMPOSITE) { ereport(ERROR, (errcode(ERRCODE_FEATURE_NOT_SUPPORTED), errmsg("function returning record called in context that cannot accept type record"))); }
BlessTupleDesc(tupdesc);
values[0] = ?; //how?
values[1] = ?; //how? values[2] = Int32GetDatum(id);
tuple = heap_form_tuple(tupdesc, values, &isnull);
PG_RETURN_DATUM(HeapTupleGetDatum(tuple));