[RFC PATCH 10/12] qapi: Generate QOM config marshalling code

[Kevin Wolf <kwolf@redhat.com>]

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
---
 backends/rng-random.c | 17 ++------
 backends/rng.c        | 17 ++------
 scripts/qapi/main.py  |  2 +
 scripts/qapi/qom.py   | 91 +++++++++++++++++++++++++++++++++++++++++++
 qapi/meson.build      |  3 ++
 5 files changed, 104 insertions(+), 26 deletions(-)
 create mode 100644 scripts/qapi/qom.py

diff --git a/backends/rng-random.c b/backends/rng-random.c
index b221308091..35738df3c6 100644
--- a/backends/rng-random.c
+++ b/backends/rng-random.c
@@ -14,6 +14,7 @@
 #include "sysemu/rng-random.h"
 #include "sysemu/rng.h"
 #include "qapi/error.h"
+#include "qapi/qapi-qom-qom.h"
 #include "qapi/visitor.h"
 #include "qapi/qmp/qerror.h"
 #include "qemu/main-loop.h"
@@ -90,7 +91,8 @@ static char *rng_random_get_filename(Object *obj, Error **errp)
     return g_strdup(s->filename);
 }
 
-static bool rng_random_config(Object *obj, const char *filename, Error **errp)
+bool qom_rng_random_config(Object *obj, bool has_filename,
+                           const char *filename, Error **errp)
 {
     RngRandom *s = RNG_RANDOM(obj);
 
@@ -100,17 +102,6 @@ static bool rng_random_config(Object *obj, const char *filename, Error **errp)
     return true;
 }
 
-static bool rng_random_marshal_config(Object *obj, Visitor *v, Error **errp)
-{
-    g_autofree char *filename = NULL;
-
-    if (!visit_type_str(v, "filename", &filename, errp)) {
-        return false;
-    }
-
-    return rng_random_config(obj, filename, errp);
-}
-
 static void rng_random_init(Object *obj)
 {
     RngRandom *s = RNG_RANDOM(obj);
@@ -148,7 +139,7 @@ static const TypeInfo rng_random_info = {
     .instance_size = sizeof(RngRandom),
     .class_init = rng_random_class_init,
     .instance_init = rng_random_init,
-    .instance_config = rng_random_marshal_config,
+    .instance_config = qom_rng_random_marshal_config,
     .instance_finalize = rng_random_finalize,
 };
 
diff --git a/backends/rng.c b/backends/rng.c
index 840daf0392..d560bd7b5d 100644
--- a/backends/rng.c
+++ b/backends/rng.c
@@ -13,6 +13,7 @@
 #include "qemu/osdep.h"
 #include "sysemu/rng.h"
 #include "qapi/error.h"
+#include "qapi/qapi-qom-qom.h"
 #include "qapi/qmp/qerror.h"
 #include "qemu/module.h"
 #include "qom/object_interfaces.h"
@@ -77,24 +78,14 @@ static void rng_backend_complete(UserCreatable *uc, Error **errp)
     rng_backend_prop_set_opened(OBJECT(uc), true, errp);
 }
 
-static bool rng_backend_config(Object *obj, bool opened, Error **errp)
+bool qom_rng_backend_config(Object *obj, bool has_opened, bool opened,
+                            Error **errp)
 {
     ERRP_GUARD();
     rng_backend_prop_set_opened(obj, opened, errp);
     return *errp == NULL;
 }
 
-static bool rng_backend_marshal_config(Object *obj, Visitor *v, Error **errp)
-{
-    bool opened;
-
-    if (!visit_type_bool(v, "opened", &opened, errp)) {
-        return false;
-    }
-
-    return rng_backend_config(obj, opened, errp);
-}
-
 static void rng_backend_free_request(RngRequest *req)
 {
     g_free(req->data);
@@ -148,7 +139,7 @@ static const TypeInfo rng_backend_info = {
     .parent = TYPE_OBJECT,
     .instance_size = sizeof(RngBackend),
     .instance_init = rng_backend_init,
-    .instance_config = rng_backend_marshal_config,
+    .instance_config = qom_rng_backend_marshal_config,
     .instance_finalize = rng_backend_finalize,
     .class_size = sizeof(RngBackendClass),
     .class_init = rng_backend_class_init,
diff --git a/scripts/qapi/main.py b/scripts/qapi/main.py
index f2ea6e0ce4..b6b4a4a74d 100644
--- a/scripts/qapi/main.py
+++ b/scripts/qapi/main.py
@@ -16,6 +16,7 @@
 from .error import QAPIError
 from .events import gen_events
 from .introspect import gen_introspect
+from .qom import gen_qom
 from .schema import QAPISchema
 from .types import gen_types
 from .visit import gen_visit
@@ -52,6 +53,7 @@ def generate(schema_file: str,
     gen_commands(schema, output_dir, prefix)
     gen_events(schema, output_dir, prefix)
     gen_introspect(schema, output_dir, prefix, unmask)
+    gen_qom(schema, output_dir, prefix)
 
 
 def main() -> int:
diff --git a/scripts/qapi/qom.py b/scripts/qapi/qom.py
new file mode 100644
index 0000000000..1cca94890f
--- /dev/null
+++ b/scripts/qapi/qom.py
@@ -0,0 +1,91 @@
+"""
+QAPI QOM boilerplate generator
+
+Copyright (c) 2021 Red Hat Inc.
+
+Authors:
+ Kevin Wolf <kwolf@redhat.com>
+
+This work is licensed under the terms of the GNU GPL, version 2.
+See the COPYING file in the top-level directory.
+"""
+
+from .common import c_name, mcgen
+from .gen import (
+    build_params,
+    QAPISchemaModularCVisitor,
+)
+from .schema import (
+    QAPISchema,
+    QAPISchemaClass,
+)
+
+
+def gen_config_decl(c: QAPISchemaClass) -> str:
+    params = build_params(c.config_type, c.config_boxed,  'Error **errp')
+    return mcgen('''
+bool qom_%(name)s_marshal_config(Object *obj, Visitor *v, Error **errp);
+bool qom_%(name)s_config(Object *obj, %(params)s);
+''', name=c.c_name(), params=params)
+
+
+def gen_config_call(c: QAPISchemaClass) -> str:
+    if c.config_boxed:
+        argstr = '&config, '
+    else:
+        assert not c.config_type.variants
+        argstr = ''
+        for m in c.config_type.members:
+            if m.optional:
+                argstr += 'config.has_%s, ' % c_name(m.name)
+            argstr += 'config.%s, ' % c_name(m.name)
+
+    return f'qom_{c.c_name()}_config(obj, {argstr}errp)'
+
+def gen_config(c: QAPISchemaClass) -> str:
+    return mcgen('''
+bool qom_%(qom_type)s_marshal_config(Object *obj, Visitor *v, Error **errp)
+{
+    %(config_name)s config = {0};
+
+    if (!visit_type_%(config_name)s_members(v, &config, errp)) {
+        return false;
+    }
+
+    return %(call)s;
+}
+
+''', qom_type=c.c_name(), config_name=c.config_type.c_name(),
+     call=gen_config_call(c))
+
+
+class QAPISchemaGenQOMVisitor(QAPISchemaModularCVisitor):
+
+    def __init__(self, prefix: str):
+        super().__init__(
+            prefix, 'qapi-qom', ' * Schema-defined QOM types',
+            None, __doc__)
+
+    def _begin_user_module(self, name: str) -> None:
+        qom = self._module_basename('qapi-qom', name)
+        types = self._module_basename('qapi-types', name)
+        visit = self._module_basename('qapi-visit', name)
+        self._genc.add(mcgen('''
+#include "qemu/osdep.h"
+#include "qapi/error.h"
+#include "%(qom)s.h"
+#include "%(types)s.h"
+#include "%(visit)s.h"
+
+''', types=types, visit=visit, qom=qom))
+
+    def visit_class(self, c: QAPISchemaClass) -> None:
+        if c.config_type:
+            self._genh.add(gen_config_decl(c))
+            self._genc.add(gen_config(c))
+
+
+def gen_qom(schema: QAPISchema, output_dir: str, prefix: str) -> None:
+    vis = QAPISchemaGenQOMVisitor(prefix)
+    schema.visit(vis)
+    vis.write(output_dir)
diff --git a/qapi/meson.build b/qapi/meson.build
index c356a385e3..10c412f1ad 100644
--- a/qapi/meson.build
+++ b/qapi/meson.build
@@ -87,6 +87,7 @@ qapi_nonmodule_outputs = [
   'qapi-init-commands.h', 'qapi-init-commands.c',
   'qapi-events.h', 'qapi-events.c',
   'qapi-emit-events.c', 'qapi-emit-events.h',
+  'qapi-qom.h', 'qapi-qom.c',
 ]
 
 # First build all sources
@@ -111,6 +112,8 @@ foreach module : qapi_all_modules
       'qapi-events-@0@.h'.format(module),
       'qapi-commands-@0@.c'.format(module),
       'qapi-commands-@0@.h'.format(module),
+      'qapi-qom-@0@.c'.format(module),
+      'qapi-qom-@0@.h'.format(module),
     ]
   endif
   if module.endswith('-target')
-- 
2.31.1