/*
* assign_func_result_transient_type
* assign typmod if the result of function is transient type.
*
*/
void
assign_func_result_transient_type(Oid funcid)
{
HeapTuple tp;
Form_pg_proc procform;
TupleDesc tupdesc;
cqContext *pcqCtx;
pcqCtx = caql_beginscan(
NULL,
cql("SELECT * FROM pg_proc "
" WHERE oid = :1 ",
ObjectIdGetDatum(funcid)));
tp = caql_getnext(pcqCtx);
caql_endscan(pcqCtx);
if (!HeapTupleIsValid(tp))
elog(ERROR, "cache lookup failed for function %u", funcid);
procform = (Form_pg_proc) GETSTRUCT(tp);
tupdesc = build_function_result_tupdesc_t(tp);
if (tupdesc == NULL)
return;
if (resolve_polymorphic_tupdesc(tupdesc,
&procform->proargtypes,
NULL))
{
if (tupdesc->tdtypeid == RECORDOID &&
tupdesc->tdtypmod < 0)
assign_record_type_typmod(tupdesc);
}
}
/*
* internal_get_result_type -- workhorse code implementing all the above
*
* funcid must always be supplied. call_expr and rsinfo can be NULL if not
* available. We will return TYPEFUNC_RECORD, and store NULL into
* *resultTupleDesc, if we cannot deduce the complete result rowtype from
* the available information.
*/
static TypeFuncClass
internal_get_result_type(Oid funcid,
Node *call_expr,
ReturnSetInfo *rsinfo,
Oid *resultTypeId,
TupleDesc *resultTupleDesc)
{
TypeFuncClass result;
HeapTuple tp;
Form_pg_proc procform;
Oid rettype;
TupleDesc tupdesc;
/* First fetch the function's pg_proc row to inspect its rettype */
tp = SearchSysCache1(PROCOID, ObjectIdGetDatum(funcid));
if (!HeapTupleIsValid(tp))
elog(ERROR, "cache lookup failed for function %u", funcid);
procform = (Form_pg_proc) GETSTRUCT(tp);
rettype = procform->prorettype;
/* Check for OUT parameters defining a RECORD result */
tupdesc = build_function_result_tupdesc_t(tp);
if (tupdesc)
{
/*
* It has OUT parameters, so it's basically like a regular composite
* type, except we have to be able to resolve any polymorphic OUT
* parameters.
*/
if (resultTypeId)
*resultTypeId = rettype;
if (resolve_polymorphic_tupdesc(tupdesc,
&procform->proargtypes,
call_expr))
{
if (tupdesc->tdtypeid == RECORDOID &&
tupdesc->tdtypmod < 0)
assign_record_type_typmod(tupdesc);
if (resultTupleDesc)
*resultTupleDesc = tupdesc;
result = TYPEFUNC_COMPOSITE;
}
else
{
if (resultTupleDesc)
*resultTupleDesc = NULL;
result = TYPEFUNC_RECORD;
}
ReleaseSysCache(tp);
return result;
}
/*
* If scalar polymorphic result, try to resolve it.
*/
if (IsPolymorphicType(rettype))
{
Oid newrettype = exprType(call_expr);
if (newrettype == InvalidOid) /* this probably should not happen */
ereport(ERROR,
(errcode(ERRCODE_DATATYPE_MISMATCH),
errmsg("could not determine actual result type for function \"%s\" declared to return type %s",
NameStr(procform->proname),
format_type_be(rettype))));
rettype = newrettype;
}
if (resultTypeId)
*resultTypeId = rettype;
if (resultTupleDesc)
*resultTupleDesc = NULL; /* default result */
/* Classify the result type */
result = get_type_func_class(rettype);
switch (result)
{
case TYPEFUNC_COMPOSITE:
if (resultTupleDesc)
*resultTupleDesc = lookup_rowtype_tupdesc_copy(rettype, -1);
/* Named composite types can't have any polymorphic columns */
break;
case TYPEFUNC_SCALAR:
break;
case TYPEFUNC_RECORD:
/* We must get the tupledesc from call context */
if (rsinfo && IsA(rsinfo, ReturnSetInfo) &&
rsinfo->expectedDesc != NULL)
{
result = TYPEFUNC_COMPOSITE;
if (resultTupleDesc)
*resultTupleDesc = rsinfo->expectedDesc;
/* Assume no polymorphic columns here, either */
}
break;
default:
break;
}
ReleaseSysCache(tp);
return result;
}