qapi: Drop unused error argument for list and implicit struct

No backend was setting an error when ending the visit of a list or
implicit struct, or when moving to the next list node.  Make the
callers a bit easier to follow by making this a part of the contract,
and removing the errp argument - callers can then unconditionally end
an object as part of cleanup without having to think about whether a
second error is dominated by a first, because there is no second
error.

A later patch will then tackle the larger task of splitting
visit_end_struct(), which can indeed set an error.

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1454075341-13658-24-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>

1 files changed, 5 insertions, 3 deletions

diff --git a/include/qapi/visitor.h b/include/qapi/visitor.h
index 997555dbd7..5e581dcf7e 100644
--- a/include/qapi/visitor.h
+++ b/include/qapi/visitor.h
@@ -1,6 +1,7 @@
 /*
  * Core Definitions for QAPI Visitor Classes
  *
+ * Copyright (C) 2012-2016 Red Hat, Inc.
  * Copyright IBM, Corp. 2011
  *
  * Authors:
@@ -32,10 +33,11 @@ void visit_start_struct(Visitor *v, const char *name, void **obj,
 void visit_end_struct(Visitor *v, Error **errp);
 void visit_start_implicit_struct(Visitor *v, void **obj, size_t size,
                                  Error **errp);
-void visit_end_implicit_struct(Visitor *v, Error **errp);
+void visit_end_implicit_struct(Visitor *v);
+
 void visit_start_list(Visitor *v, const char *name, Error **errp);
-GenericList *visit_next_list(Visitor *v, GenericList **list, Error **errp);
-void visit_end_list(Visitor *v, Error **errp);
+GenericList *visit_next_list(Visitor *v, GenericList **list);
+void visit_end_list(Visitor *v);
 
 /**
  * Check if an optional member @name of an object needs visiting.