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, 6 insertions, 10 deletions

diff --git a/net/net.c b/net/net.c
index 7793366..a5e2da2 100644
--- a/net/net.c
+++ b/net/net.c
@@ -1090,7 +1090,7 @@ void netdev_add(QemuOpts *opts, Error **errp)
     net_client_init(opts, 1, errp);
 }
 
-int qmp_netdev_add(Monitor *mon, const QDict *qdict, QObject **ret)
+void qmp_netdev_add(QDict *qdict, QObject **ret, Error **errp)
 {
     Error *local_err = NULL;
     QemuOptsList *opts_list;
@@ -1098,26 +1098,22 @@ int qmp_netdev_add(Monitor *mon, const QDict *qdict, QObject **ret)
 
     opts_list = qemu_find_opts_err("netdev", &local_err);
     if (local_err) {
-        goto exit_err;
+        goto out;
     }
 
     opts = qemu_opts_from_qdict(opts_list, qdict, &local_err);
     if (local_err) {
-        goto exit_err;
+        goto out;
     }
 
     netdev_add(opts, &local_err);
     if (local_err) {
         qemu_opts_del(opts);
-        goto exit_err;
+        goto out;
     }
 
-    return 0;
-
-exit_err:
-    qerror_report_err(local_err);
-    error_free(local_err);
-    return -1;
+out:
+    error_propagate(errp, local_err);
 }
 
 void qmp_netdev_del(const char *id, Error **errp)