[Qemu-devel] [PATCH RFC v2 23/47] qapi: New QAPISchemaVisitor

[Markus Armbruster]

The visitor will help keeping the code generation code simple and
reasonably separated from QAPISchema details.

Signed-off-by: Markus Armbruster <address@hidden>
---
 scripts/qapi.py | 44 ++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 44 insertions(+)

diff --git a/scripts/qapi.py b/scripts/qapi.py
index b5fa1be..cac7ab5 100644
--- a/scripts/qapi.py
+++ b/scripts/qapi.py
@@ -767,6 +767,28 @@ class QAPISchemaEntity(object):
         return c_name(self.name)
     def check(self, schema):
         pass
+    def visit(self, visitor):
+        pass
+
+class QAPISchemaVisitor(object):
+    def visit_begin(self):
+        pass
+    def visit_end(self):
+        pass
+    def visit_builtin_type(self, name, info, json_type):
+        pass
+    def visit_enum_type(self, name, info, values):
+        pass
+    def visit_array_type(self, name, info, element_type):
+        pass
+    def visit_object_type(self, name, info, base, members, variants):
+        pass
+    def visit_alternate_type(self, name, info, variants):
+        pass
+    def visit_command(self, name, info, args, rets, gen, success_response):
+        pass
+    def visit_event(self, name, info, data):
+        pass
 
 class QAPISchemaType(QAPISchemaEntity):
     def c_type(self, is_param=False):
@@ -804,6 +826,8 @@ class QAPISchemaBuiltinType(QAPISchemaType):
         return self.c_null_val
     def json_type(self):
         return self.json_type_name
+    def visit(self, visitor):
+        visitor.visit_builtin_type(self.name, self.info, self.json_type())
 
 class QAPISchemaEnumType(QAPISchemaType):
     def __init__(self, name, info, values):
@@ -817,6 +841,8 @@ class QAPISchemaEnumType(QAPISchemaType):
         return c_enum_const(self.name, self.values[0])
     def json_type(self):
         return 'string'
+    def visit(self, visitor):
+        visitor.visit_enum_type(self.name, self.info, self.values)
 
 class QAPISchemaArrayType(QAPISchemaType):
     def __init__(self, name, info, element_type):
@@ -827,6 +853,8 @@ class QAPISchemaArrayType(QAPISchemaType):
     def check(self, schema):
         self.element_type = schema.lookup_type(self.element_type_name)
         assert self.element_type
+    def visit(self, visitor):
+        visitor.visit_array_type(self.name, self.info, self.element_type)
 
 class QAPISchemaObjectType(QAPISchemaType):
     def __init__(self, name, info, base, local_members, variants):
@@ -868,6 +896,9 @@ class QAPISchemaObjectType(QAPISchemaType):
         return QAPISchemaType.c_type(self)
     def json_type(self):
         return 'object'
+    def visit(self, visitor):
+        visitor.visit_object_type(self.name, self.info,
+                                  self.base, self.local_members, self.variants)
 
 class QAPISchemaObjectTypeMember(object):
     def __init__(self, name, typ, optional):
@@ -931,6 +962,8 @@ class QAPISchemaAlternateType(QAPISchemaType):
         self.variants = variants
     def check(self, schema):
         self.variants.check(schema, [], {})
+    def visit(self, visitor):
+        visitor.visit_alternate_type(self.name, self.info, self.variants)
 
 class QAPISchemaCommand(QAPISchemaEntity):
     def __init__(self, name, info, args, rets, gen, success_response):
@@ -953,6 +986,9 @@ class QAPISchemaCommand(QAPISchemaEntity):
             self.rets = schema.lookup_type(self.rets_name)
             assert isinstance(self.rets, QAPISchemaType)
             self.rets.check(schema)
+    def visit(self, visitor):
+        visitor.visit_command(self.name, self.info, self.args, self.rets,
+                              self.gen, self.success_response)
 
 class QAPISchemaEvent(QAPISchemaEntity):
     def __init__(self, name, info, data):
@@ -965,6 +1001,8 @@ class QAPISchemaEvent(QAPISchemaEntity):
             self.data = schema.lookup_type(self.data_name)
             assert isinstance(self.data, QAPISchemaObjectType)
             self.data.check(schema)
+    def visit(self, visitor):
+        visitor.visit_event(self.name, self.info, self.data)
 
 class QAPISchema(object):
     def __init__(self, fname):
@@ -1152,6 +1190,12 @@ class QAPISchema(object):
         for ent in self.entity_dict.values():
             ent.check(self)
 
+    def visit(self, visitor):
+        visitor.visit_begin()
+        for name in sorted(self.entity_dict.keys()):
+            self.entity_dict[name].visit(visitor)
+        visitor.visit_end()
+
 #
 # Code generation helpers
 #
-- 
1.9.3