Function numeric_avg_deserialize

src/backend/utils/adt/numeric.c:5091–5145

* numeric_avg_deserialize * Deserialize bytea into NumericAggState for numeric aggregates that * don't require sumX2. Deserializes bytea into NumericAggState using the * standard pq API. * * numeric_avg_serialize(numeric_avg_deserialize(bytea)) must result in a value * which matches the original bytea value. */

 * which matches the original bytea value.
 */
Datum
numeric_avg_deserialize(PG_FUNCTION_ARGS)
{
	bytea	   *sstate;
	NumericAggState *result;
	Datum		temp;
	NumericVar	tmp_var;
	StringInfoData buf;

	if (!AggCheckCallContext(fcinfo, NULL))
		elog(ERROR, "aggregate function called in non-aggregate context");

	sstate = PG_GETARG_BYTEA_PP(0);

	/*
	 * Copy the bytea into a StringInfo so that we can "receive" it using the
	 * standard recv-function infrastructure.
	 */
	initStringInfo(&buf);
	appendBinaryStringInfo(&buf,
						   VARDATA_ANY(sstate), VARSIZE_ANY_EXHDR(sstate));

	result = makeNumericAggStateCurrentContext(false);

	/* N */
	result->N = pq_getmsgint64(&buf);

	/* sumX */
	temp = DirectFunctionCall3(numeric_recv,
							   PointerGetDatum(&buf),
							   ObjectIdGetDatum(InvalidOid),
							   Int32GetDatum(-1));
	init_var_from_num(DatumGetNumeric(temp), &tmp_var);
	accum_sum_add(&(result->sumX), &tmp_var);

	/* maxScale */
	result->maxScale = pq_getmsgint(&buf, 4);

	/* maxScaleCount */
	result->maxScaleCount = pq_getmsgint64(&buf);

	/* NaNcount */
	result->NaNcount = pq_getmsgint64(&buf);

	/* pInfcount */
	result->pInfcount = pq_getmsgint64(&buf);

	/* nInfcount */
	result->nInfcount = pq_getmsgint64(&buf);

	pq_getmsgend(&buf);
	pfree(buf.data);

	PG_RETURN_POINTER(result);
}


/*