qapi script: support enum type as discriminator in union
By default, any union will automatically generate a enum type as
"[UnionName]Kind" in C code, and it is duplicated when the discriminator
is specified as a pre-defined enum type in schema. After this patch,
the pre-defined enum type will be really used as the switch case
condition in generated C code, if discriminator is an enum field.
Signed-off-by: Wenchao Xia <wenchaoqemu@gmail.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
diff --git a/scripts/qapi-visit.py b/scripts/qapi-visit.py
index 0baaf60..45ce3a9 100644
--- a/scripts/qapi-visit.py
+++ b/scripts/qapi-visit.py
@@ -259,10 +259,16 @@
assert not base
return generate_visit_anon_union(name, members)
- # There will always be a discriminator in the C switch code, by default it
- # is an enum type generated silently as "'%sKind' % (name)"
- ret = generate_visit_enum('%sKind' % name, members.keys())
- disc_type = '%sKind' % (name)
+ enum_define = discriminator_find_enum_define(expr)
+ if enum_define:
+ # Use the enum type as discriminator
+ ret = ""
+ disc_type = enum_define['enum_name']
+ else:
+ # There will always be a discriminator in the C switch code, by default it
+ # is an enum type generated silently as "'%sKind' % (name)"
+ ret = generate_visit_enum('%sKind' % name, members.keys())
+ disc_type = '%sKind' % (name)
if base:
base_fields = find_struct(base)['data']
@@ -298,15 +304,16 @@
pop_indent()
if not discriminator:
- desc_type = "type"
+ disc_key = "type"
else:
- desc_type = discriminator
+ disc_key = discriminator
ret += mcgen('''
- visit_type_%(name)sKind(m, &(*obj)->kind, "%(type)s", &err);
+ visit_type_%(disc_type)s(m, &(*obj)->kind, "%(disc_key)s", &err);
if (!err) {
switch ((*obj)->kind) {
''',
- name=name, type=desc_type)
+ disc_type = disc_type,
+ disc_key = disc_key)
for key in members:
if not discriminator:
@@ -517,7 +524,11 @@
ret += generate_visit_list(expr['union'], expr['data'])
fdef.write(ret)
- ret = generate_decl_enum('%sKind' % expr['union'], expr['data'].keys())
+ enum_define = discriminator_find_enum_define(expr)
+ ret = ""
+ if not enum_define:
+ ret = generate_decl_enum('%sKind' % expr['union'],
+ expr['data'].keys())
ret += generate_declaration(expr['union'], expr['data'])
fdecl.write(ret)
elif expr.has_key('enum'):