qemu-nbd: Use user_creatable_process_cmdline() for --object

This switches qemu-nbd from a QemuOpts-based parser for --object to
user_creatable_process_cmdline() which uses a keyval parser and enforces
the QAPI schema.

Apart from being a cleanup, this makes non-scalar properties accessible.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>

qemu-nbd.c

@@ -401,24 +401,6 @@ static QemuOptsList file_opts = {
     },
 };
 
-static QemuOptsList qemu_object_opts = {
-    .name = "object",
-    .implied_opt_name = "qom-type",
-    .head = QTAILQ_HEAD_INITIALIZER(qemu_object_opts.head),
-    .desc = {
-        { }
-    },
-};
-
-static bool qemu_nbd_object_print_help(const char *type, QemuOpts *opts)
-{
-    if (user_creatable_print_help(type, opts)) {
-        exit(0);
-    }
-    return true;
-}
-
-
 static QCryptoTLSCreds *nbd_get_tls_creds(const char *id, bool list,
                                           Error **errp)
 {
@@ -594,7 +576,6 @@ int main(int argc, char **argv)
     qcrypto_init(&error_fatal);
 
     module_call_init(MODULE_INIT_QOM);
-    qemu_add_opts(&qemu_object_opts);
     qemu_add_opts(&qemu_trace_opts);
     qemu_init_exec_dir(argv[0]);
 
@@ -747,14 +728,9 @@ int main(int argc, char **argv)
         case '?':
             error_report("Try `%s --help' for more information.", argv[0]);
             exit(EXIT_FAILURE);
-        case QEMU_NBD_OPT_OBJECT: {
-            QemuOpts *opts;
-            opts = qemu_opts_parse_noisily(&qemu_object_opts,
-                                           optarg, true);
-            if (!opts) {
-                exit(EXIT_FAILURE);
-            }
-        }   break;
+        case QEMU_NBD_OPT_OBJECT:
+            user_creatable_process_cmdline(optarg);
+            break;
         case QEMU_NBD_OPT_TLSCREDS:
             tlscredsid = optarg;
             break;
@@ -802,10 +778,6 @@ int main(int argc, char **argv)
         export_name = "";
     }
 
-    qemu_opts_foreach(&qemu_object_opts,
-                      user_creatable_add_opts_foreach,
-                      qemu_nbd_object_print_help, &error_fatal);
-
     if (!trace_init_backends()) {
         exit(1);
     }