Function SendFunctionResult

src/backend/tcop/fastpath.c:66–110

---------------- * SendFunctionResult * ---------------- */

 * ----------------
 */
static void
SendFunctionResult(Datum retval, bool isnull, Oid rettype, int16 format)
{
	StringInfoData buf;

	pq_beginmessage(&buf, 'V');

	if (isnull)
	{
		pq_sendint32(&buf, -1);
	}
	else
	{
		if (format == 0)
		{
			Oid			typoutput;
			bool		typisvarlena;
			char	   *outputstr;

			getTypeOutputInfo(rettype, &typoutput, &typisvarlena);
			outputstr = OidOutputFunctionCall(typoutput, retval);
			pq_sendcountedtext(&buf, outputstr, strlen(outputstr), false);
			pfree(outputstr);
		}
		else if (format == 1)
		{
			Oid			typsend;
			bool		typisvarlena;
			bytea	   *outputbytes;

			getTypeBinaryOutputInfo(rettype, &typsend, &typisvarlena);
			outputbytes = OidSendFunctionCall(typsend, retval);
			pq_sendint32(&buf, VARSIZE(outputbytes) - VARHDRSZ);
			pq_sendbytes(&buf, VARDATA(outputbytes),
						 VARSIZE(outputbytes) - VARHDRSZ);
			pfree(outputbytes);
		}
		else
			ereport(ERROR,
					(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
					 errmsg("unsupported format code: %d", format)));
	}

	pq_endmessage(&buf);
}

/*
 * fetch_fp_info