Kevin Wolf <kwolf(a)redhat.com> writes:
The implementation for --object can be shared between
qemu-storage-daemon and other binaries, so move it into a function in
qom/object_interfaces.c that is accessible from everywhere.
This also requires moving the implementation of qmp_object_add() into a
new user_creatable_add_qapi(), because qom/qom-qmp-cmds.c is not linked
for tools.
user_creatable_print_help_from_qdict() can become static now.
Signed-off-by: Kevin Wolf <kwolf(a)redhat.com>
Acked-by: Peter Krempa <pkrempa(a)redhat.com>
Reviewed-by: Eric Blake <eblake(a)redhat.com>
---
include/qom/object_interfaces.h | 41 +++++++++++++++--------
qom/object_interfaces.c | 50 +++++++++++++++++++++++++++-
qom/qom-qmp-cmds.c | 20 +----------
storage-daemon/qemu-storage-daemon.c | 24 ++-----------
4 files changed, 80 insertions(+), 55 deletions(-)
diff --git a/include/qom/object_interfaces.h b/include/qom/object_interfaces.h
index 5299603f50..1e6c51b541 100644
--- a/include/qom/object_interfaces.h
+++ b/include/qom/object_interfaces.h
@@ -2,6 +2,7 @@
#define OBJECT_INTERFACES_H
#include "qom/object.h"
+#include "qapi/qapi-types-qom.h"
#include "qapi/visitor.h"
#define TYPE_USER_CREATABLE "user-creatable"
@@ -86,6 +87,18 @@ Object *user_creatable_add_type(const char *type, const char *id,
const QDict *qdict,
Visitor *v, Error **errp);
+/**
+ * user_creatable_add_qapi:
+ * @options: the object definition
+ * @errp: if an error occurs, a pointer to an area to store the error
+ *
+ * Create an instance of the user creatable object according to the
+ * options passed in @opts as described in the QAPI schema documentation.
+ *
+ * Returns: the newly created object or NULL on error
+ */
+void user_creatable_add_qapi(ObjectOptions *options, Error **errp);
+
/**
* user_creatable_add_opts:
* @opts: the object definition
@@ -131,6 +144,21 @@ typedef bool (*user_creatable_add_opts_predicate)(const char
*type);
int user_creatable_add_opts_foreach(void *opaque,
QemuOpts *opts, Error **errp);
+/**
+ * user_creatable_process_cmdline:
+ * @optarg: the object definition string as passed on the command line
+ *
+ * Create an instance of the user creatable object by parsing optarg
+ * with a keyval parser and implicit key 'qom-type', converting the
+ * result to ObjectOptions and calling into qmp_object_add().
+ *
+ * If a help option is given, print help instead and exit.
+ *
+ * This function is only meant to be called during command line parsing.
+ * It exits the process on failure or after printing help.
+ */
+void user_creatable_process_cmdline(const char *optarg);
+
/**
* user_creatable_print_help:
* @type: the QOM type to be added
@@ -145,19 +173,6 @@ int user_creatable_add_opts_foreach(void *opaque,
*/
bool user_creatable_print_help(const char *type, QemuOpts *opts);
-/**
- * user_creatable_print_help_from_qdict:
- * @args: options to create
- *
- * Prints help considering the other options given in @args (if "qom-type" is
- * given and valid, print properties for the type, otherwise print valid types)
- *
- * In contrast to user_creatable_print_help(), this function can't return that
- * no help was requested. It should only be called if we know that help is
- * requested and it will always print some help.
- */
-void user_creatable_print_help_from_qdict(QDict *args);
-
/**
* user_creatable_del:
* @id: the unique ID for the object
diff --git a/qom/object_interfaces.c b/qom/object_interfaces.c
index 02c3934329..2eaf9971f5 100644
--- a/qom/object_interfaces.c
+++ b/qom/object_interfaces.c
@@ -2,10 +2,13 @@
#include "qemu/cutils.h"
#include "qapi/error.h"
+#include "qapi/qapi-commands-qom.h"
+#include "qapi/qapi-visit-qom.h"
#include "qapi/qmp/qdict.h"
#include "qapi/qmp/qerror.h"
#include "qapi/qmp/qjson.h"
#include "qapi/qobject-input-visitor.h"
+#include "qapi/qobject-output-visitor.h"
#include "qom/object_interfaces.h"
#include "qemu/help_option.h"
#include "qemu/id.h"
@@ -113,6 +116,29 @@ out:
return obj;
}
+void user_creatable_add_qapi(ObjectOptions *options, Error **errp)
+{
+ Visitor *v;
+ QObject *qobj;
+ QDict *props;
+ Object *obj;
+
+ v = qobject_output_visitor_new(&qobj);
+ visit_type_ObjectOptions(v, NULL, &options, &error_abort);
+ visit_complete(v, &qobj);
+ visit_free(v);
+
+ props = qobject_to(QDict, qobj);
+ qdict_del(props, "qom-type");
+ qdict_del(props, "id");
+
+ v = qobject_input_visitor_new(QOBJECT(props));
+ obj = user_creatable_add_type(ObjectType_str(options->qom_type),
+ options->id, props, v, errp);
+ object_unref(obj);
+ visit_free(v);
+}
+
Observation, not objection:
1. QMP core parses JSON text into QObject, passes to generated
marshaller.
2. Marshaller converts QObject to ObjectOptions with the QObject input
visitor, passes to qmp_object_add().
3. qmp_object_add() wraps around user_creatable_add_qapi().
4. user_creatable_add_qapi() converts right back to QObject with the
QObject output visitor. It splits the result into qom_type, id and
the rest, and passes all three to user_creatable_add_type().
5. user_creatable_add_type() performs a virtual visit with the QObject
input visitor. The outermost object it visits itself, its children
it visits by calling object_property_set().
I sure hope we wouldn't write it this way from scratch :)
I think your patch is a reasonable step towards a QOM that is at peace
with QAPI. But there's plenty of work left.
[...]