qapi: Replace start_optional()/end_optional() by optional()

Semantics of end_optional() differ subtly from the other end_FOO()
callbacks: when start_FOO() succeeds, the matching end_FOO() gets
called regardless of what happens in between.  end_optional() gets
called only when everything in between succeeds as well.  Entirely
undocumented, like all of the visitor API.

The only user of Visitor Callback end_optional() never did anything,
and was removed in commit 9f9ab46.

I'm about to clean up error handling in the generated visitor code,
and end_optional() is in my way.  No users mean no test cases, and
making non-trivial cleanup transformations without test cases doesn't
strike me as a good idea.

Drop end_optional(), and rename start_optional() to optional().  We
can always go back to a pair of callbacks when we have an actual need.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>

1 files changed, 3 insertions, 3 deletions

diff --git a/qapi/string-input-visitor.c b/qapi/string-input-visitor.c
index 793548ae3a..5780944792 100644
--- a/qapi/string-input-visitor.c
+++ b/qapi/string-input-visitor.c
@@ -120,8 +120,8 @@ static void parse_type_number(Visitor *v, double *obj, const char *name,
     *obj = val;
 }
 
-static void parse_start_optional(Visitor *v, bool *present,
-                                 const char *name, Error **errp)
+static void parse_optional(Visitor *v, bool *present, const char *name,
+                           Error **errp)
 {
     StringInputVisitor *siv = DO_UPCAST(StringInputVisitor, visitor, v);
 
@@ -155,7 +155,7 @@ StringInputVisitor *string_input_visitor_new(const char *str)
     v->visitor.type_bool = parse_type_bool;
     v->visitor.type_str = parse_type_str;
     v->visitor.type_number = parse_type_number;
-    v->visitor.start_optional = parse_start_optional;
+    v->visitor.optional = parse_optional;
 
     v->string = str;
     return v;