[Qemu-devel] Re: [PATCH 2/7] monitor: Handle new and old style handlers

[Paolo Bonzini]

On 09/16/2009 11:32 PM, Luiz Capitulino wrote:
> +    return (cmd->user_print == NULL ? 0 : 1);

cmd->user_print != NULL.

I would actually inline it at the use point.  Also, calling a function 
with an extra argument is fine, so while keeping the void* handler you 
can do:

+        QObject *data = NULL;
+        int (*handler_new)(Monitor *mon,
+                           const QDict *params, QObject **ret_data);

+        handler_new = cmd->handler;
+        handler_new(mon, qdict, &data);

+        if (cmd->user_print)
+                cmd->user_print(mon, data);
+        if (data)
+                qobject_decref(data);

If you do not like calling the function with the "wrong" number of 
arguments, you can mass-convert the functions to the new prototype new 
and leave anyway user_print == NULL.

What are the plans for the return code of handler_new?

Paolo