Function fmgr_sql_validator

src/backend/catalog/pg_proc.c:892–1056

* Validator for SQL language functions * * Parse it here in order to be sure that it contains no syntax errors. */

 * Parse it here in order to be sure that it contains no syntax errors.
 */
Datum
fmgr_sql_validator(PG_FUNCTION_ARGS)
{
	Oid			funcoid = PG_GETARG_OID(0);
	HeapTuple	tuple;
	Form_pg_proc proc;
	List	   *raw_parsetree_list;
	List	   *querytree_list;
	ListCell   *lc;
	bool		isnull;
	Datum		tmp;
	char	   *prosrc;
	parse_error_callback_arg callback_arg;
	ErrorContextCallback sqlerrcontext;
	bool		haspolyarg;
	int			i;

	if (!CheckFunctionValidatorAccess(fcinfo->flinfo->fn_oid, funcoid))
		PG_RETURN_VOID();

	tuple = SearchSysCache1(PROCOID, ObjectIdGetDatum(funcoid));
	if (!HeapTupleIsValid(tuple))
		elog(ERROR, "cache lookup failed for function %u", funcoid);
	proc = (Form_pg_proc) GETSTRUCT(tuple);

	/* Disallow pseudotype result */
	/* except for RECORD, VOID, or polymorphic */
	if (get_typtype(proc->prorettype) == TYPTYPE_PSEUDO &&
		proc->prorettype != RECORDOID &&
		proc->prorettype != VOIDOID &&
		!IsPolymorphicType(proc->prorettype))
		ereport(ERROR,
				(errcode(ERRCODE_INVALID_FUNCTION_DEFINITION),
				 errmsg("SQL functions cannot return type %s",
						format_type_be(proc->prorettype))));

	/* Disallow pseudotypes in arguments */
	/* except for polymorphic */
	haspolyarg = false;
	for (i = 0; i < proc->pronargs; i++)
	{
		if (get_typtype(proc->proargtypes.values[i]) == TYPTYPE_PSEUDO)
		{
			if (IsPolymorphicType(proc->proargtypes.values[i]))
				haspolyarg = true;
			else
				ereport(ERROR,
						(errcode(ERRCODE_INVALID_FUNCTION_DEFINITION),
						 errmsg("SQL functions cannot have arguments of type %s",
								format_type_be(proc->proargtypes.values[i]))));
		}
	}

	/* Postpone body checks if !check_function_bodies */
	if (check_function_bodies)
	{
		tmp = SysCacheGetAttr(PROCOID, tuple, Anum_pg_proc_prosrc, &isnull);
		if (isnull)