qapi: Support downstream alternates

Enhance the testsuite to cover downstream alternates, including
whether the branch name or type is downstream.  Update the
generator to mangle alternate names in the appropriate places.
Signed-off-by: NEric Blake <eblake@redhat.com>
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>

scripts/qapi-types.py

@@ -174,16 +174,17 @@ def generate_alternate_qtypes(expr):
     ret = mcgen('''
 const int %(name)s_qtypes[QTYPE_MAX] = {
 ''',
-    name=name)
+                name=c_name(name))
 
     for key in members:
         qtype = find_alternate_member_qtype(members[key])
         assert qtype, "Invalid alternate member"
 
         ret += mcgen('''
-    [ %(qtype)s ] = %(enum_const)s,
+    [%(qtype)s] = %(enum_const)s,
 ''',
-        qtype = qtype, enum_const = c_enum_const(name + 'Kind', key))
+                     qtype = qtype,
+                     enum_const = c_enum_const(name + 'Kind', key))
 
     ret += mcgen('''
 };

scripts/qapi-visit.py

@@ -202,11 +202,11 @@ void visit_type_%(name)s(Visitor *m, %(name)s **obj, const char *name, Error **e
     }
     switch ((*obj)->kind) {
 ''',
-    name=name)
+                name=c_name(name))
 
     # For alternate, always use the default enum type automatically generated
-    # as "'%sKind' % (name)"
-    disc_type = '%sKind' % (name)
+    # as name + 'Kind'
+    disc_type = c_name(name) + 'Kind'
 
     for key in members:
         assert (members[key] in builtin_types.keys()

tests/qapi-schema/qapi-schema-test.json

@@ -120,3 +120,5 @@
 { 'union': '__org.qemu_x-Union2', 'base': '__org.qemu_x-Base',
   'discriminator': '__org.qemu_x-member1',
   'data': { '__org.qemu_x-value': '__org.qemu_x-Struct2' } }
+{ 'alternate': '__org.qemu_x-Alt',
+  'data': { '__org.qemu_x-branch': 'str', 'b': '__org.qemu_x-Base' } }

tests/qapi-schema/qapi-schema-test.out

@@ -28,12 +28,14 @@
  OrderedDict([('struct', '__org.qemu_x-Struct'), ('base', '__org.qemu_x-Base'), ('data', OrderedDict([('__org.qemu_x-member2', 'str')]))]),
  OrderedDict([('union', '__org.qemu_x-Union1'), ('data', OrderedDict([('__org.qemu_x-branch', 'str')]))]),
  OrderedDict([('struct', '__org.qemu_x-Struct2'), ('data', OrderedDict([('array', ['__org.qemu_x-Union1'])]))]),
- OrderedDict([('union', '__org.qemu_x-Union2'), ('base', '__org.qemu_x-Base'), ('discriminator', '__org.qemu_x-member1'), ('data', OrderedDict([('__org.qemu_x-value', '__org.qemu_x-Struct2')]))])]
+ OrderedDict([('union', '__org.qemu_x-Union2'), ('base', '__org.qemu_x-Base'), ('discriminator', '__org.qemu_x-member1'), ('data', OrderedDict([('__org.qemu_x-value', '__org.qemu_x-Struct2')]))]),
+ OrderedDict([('alternate', '__org.qemu_x-Alt'), ('data', OrderedDict([('__org.qemu_x-branch', 'str'), ('b', '__org.qemu_x-Base')]))])]
 [{'enum_name': 'EnumOne', 'enum_values': ['value1', 'value2', 'value3']},
  {'enum_name': '__org.qemu_x-Enum', 'enum_values': ['__org.qemu_x-value']},
  {'enum_name': 'UserDefAlternateKind', 'enum_values': None},
  {'enum_name': 'UserDefNativeListUnionKind', 'enum_values': None},
- {'enum_name': '__org.qemu_x-Union1Kind', 'enum_values': None}]
+ {'enum_name': '__org.qemu_x-Union1Kind', 'enum_values': None},
+ {'enum_name': '__org.qemu_x-AltKind', 'enum_values': None}]
 [OrderedDict([('struct', 'NestedEnumsOne'), ('data', OrderedDict([('enum1', 'EnumOne'), ('*enum2', 'EnumOne'), ('enum3', 'EnumOne'), ('*enum4', 'EnumOne')]))]),
  OrderedDict([('struct', 'UserDefZero'), ('data', OrderedDict([('integer', 'int')]))]),
  OrderedDict([('struct', 'UserDefOne'), ('base', 'UserDefZero'), ('data', OrderedDict([('string', 'str'), ('*enum1', 'EnumOne')]))]),