qmp: Wean off qerror_report()

The traditional QMP command handler interface

    int qmp_FOO(Monitor *mon, const QDict *params, QObject **ret_data);

doesn't provide for returning an Error object.  Instead, the handler
is expected to stash it in the monitor with qerror_report().

When we rebased QMP on top of QAPI, we didn't change this interface.
Instead, commit 776574d introduced "middle mode" as a temporary aid
for converting existing QMP commands to QAPI one by one.  More than
three years later, we're still using it.

Middle mode has two effects:

* Instead of the native input marshallers

      static void qmp_marshal_input_FOO(QDict *, QObject **, Error **)

  it generates input marshallers conforming to the traditional QMP
  command handler interface.

* It suppresses generation of code to register them with
  qmp_register_command()

  This permits giving them internal linkage.

As long as we need qmp-commands.hx, we can't use the registry behind
qmp_register_command(), so the latter has to stay for now.

The former has to go to get rid of qerror_report().  Changing all QMP
commands to fit the QAPI mold in one go was impractical back when we
started, but by now there are just a few stragglers left:
do_qmp_capabilities(), qmp_qom_set(), qmp_qom_get(), qmp_object_add(),
qmp_netdev_add(), do_device_add().

Switch middle mode to generate native input marshallers, and adapt the
stragglers.  Simplifies both the monitor code and the stragglers.

Rename do_qmp_capabilities() to qmp_capabilities(), and
do_device_add() to qmp_device_add, because that's how QMP command
handlers are named today.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Luiz Capitulino <lcapitulino@redhat.com>

1 files changed, 3 insertions, 4 deletions

diff --git a/include/monitor/monitor.h b/include/monitor/monitor.h
index 88644ceda7..33c28a43bf 100644
--- a/include/monitor/monitor.h
+++ b/include/monitor/monitor.h
@@ -44,10 +44,9 @@ void monitor_read_command(Monitor *mon, int show_prompt);
 int monitor_read_password(Monitor *mon, ReadLineFunc *readline_func,
                           void *opaque);
 
-int qmp_qom_set(Monitor *mon, const QDict *qdict, QObject **ret);
-
-int qmp_qom_get(Monitor *mon, const QDict *qdict, QObject **ret);
-int qmp_object_add(Monitor *mon, const QDict *qdict, QObject **ret);
+void qmp_qom_set(QDict *qdict, QObject **ret, Error **errp);
+void qmp_qom_get(QDict *qdict, QObject **ret, Error **errp);
+void qmp_object_add(QDict *qdict, QObject **ret, Error **errp);
 void object_add(const char *type, const char *id, const QDict *qdict,
                 Visitor *v, Error **errp);