Re: [Qemu-devel] [PATCH 3/7] monitor: do_info(): handle new and old info handlers

[Markus Armbruster <armbru@redhat.com>]

Luiz Capitulino <lcapitulino@redhat.com> writes:

> do_info() is special, its job is to call 'info handlers'.
> This is similar to what monitor_handle_command() does,
> therefore do_info() also has to distinguish among new and
> old style info handlers.
>
> This commit converts do_info() to the new QObject style and
> makes the appropriate changes so that it can handle both
> info handlers styles.
>
> In the future, when all handlers are converted to QObject's
> style, it will be possible to share more code with
> monitor_handle_command().
>
> Also note that this commit adds a new function called
> monitor_print_nothing(), which will be used by converted
> handlers that don't have data to print in the user protocol.
>
> Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
> ---
>  monitor.c       |   44 ++++++++++++++++++++++++++++++++------------
>  qemu-monitor.hx |    2 +-
>  2 files changed, 33 insertions(+), 13 deletions(-)
>
> diff --git a/monitor.c b/monitor.c
> index 17754fb..cfbedf8 100644
> --- a/monitor.c
> +++ b/monitor.c
[...]
> @@ -284,24 +289,39 @@ static void do_commit(Monitor *mon, const QDict *qdict)
>      }
>  }
>  
> -static void do_info(Monitor *mon, const QDict *qdict)
> +static int do_info(Monitor *mon, const QDict *qdict, QObject **ret_data)
>  {
> +    int ret = 0;
>      const mon_cmd_t *cmd;
>      const char *item = qdict_get_try_str(qdict, "item");
> -    void (*handler)(Monitor *);
>  
> -    if (!item)
> -        goto help;
> -    for(cmd = info_cmds; cmd->name != NULL; cmd++) {
> +    if (!item) {
> +        help_cmd(mon, "info");
> +        return 0;
> +    }
> +
> +    for (cmd = info_cmds; cmd->name != NULL; cmd++) {
>          if (compare_cmd(item, cmd->name))
> -            goto found;
> +            break;
>      }
> - help:
> -    help_cmd(mon, "info");
> -    return;
> - found:
> -    handler = cmd->handler;
> -    handler(mon);
> +
> +    if (cmd->name == NULL)
> +        return -1;
> +
> +    if (monitor_handler_ported(cmd)) {
> +        int (*handler_new)(Monitor *mon, QObject **ret_data);
> +
> +        handler_new = cmd->handler;
> +        ret = handler_new(mon, ret_data);
> +
> +        cmd->user_print(mon, *ret_data);
> +    } else {
> +        void (*handler_old)(Monitor *mon);
> +        handler_old = cmd->handler;
> +        handler_old(mon);
> +    }
> +
> +    return ret;
>  }
>  
>  static void do_info_version(Monitor *mon)

Looks like this changes do_info() to fail without printing help when the
"item" argument is not recognized.  Fine with me, just mention it in the
commit message, please.

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