Re: [Qemu-devel] [PATCH 10/19] Add a query-machines command to QMP

[Anthony Liguori <anthony@codemonkey.ws>]

On 06/07/2010 09:42 AM, Daniel P. Berrange wrote:
> Add a new QMP monitor command 'query-machines' to discover what
> machines are defined in the QEMU binary. This is an easily
> parsable replacement for 'qemu -M ?'
>
>      [
>          {
>              "name": "pc-0.13",
>              "description": "Standard PC",
>              "default": 0
>          },
>          {
>              "name": "pc",
>              "description": "Standard PC",
>              "canonical": "pc-0.13",
>              "default": 1
>          },
>          {
>              "name": "pc-0.12",
>              "description": "Standard PC",
>              "default": 0
>          },
>          ....
>      ]
>
> No legacy readline monitor output is provided.
>
> In the future it would be desirable for each machine's QDict to
> also include details of any qdev devices that are included by
> default in the machine type.
>
> Signed-off-by: Daniel P. Berrange<berrange@redhat.com>
> ---
>   hw/boards.h |    1 +
>   monitor.c   |    9 +++++++
>   vl.c        |   70 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
>   3 files changed, 80 insertions(+), 0 deletions(-)
>
> diff --git a/hw/boards.h b/hw/boards.h
> index 6f0f0d7..2f6003d 100644
> --- a/hw/boards.h
> +++ b/hw/boards.h
> @@ -32,6 +32,7 @@ typedef struct QEMUMachine {
>   } QEMUMachine;
>
>   int qemu_register_machine(QEMUMachine *m);
> +void do_info_machines(Monitor *mon, QObject **data);
>
>   extern QEMUMachine *current_machine;
>
> diff --git a/monitor.c b/monitor.c
> index f0406e8..b6aa2b4 100644
> --- a/monitor.c
> +++ b/monitor.c
> @@ -55,6 +55,7 @@
>   #include "json-streamer.h"
>   #include "json-parser.h"
>   #include "osdep.h"
> +#include "hw/boards.h"
>
>   //#define DEBUG
>   //#define DEBUG_COMPLETION
> @@ -2449,6 +2450,14 @@ static const mon_cmd_t info_cmds[] = {
>           .mhandler.info_new = do_info_version,
>       },
>       {
> +        .name       = "machines",
> +        .args_type  = "",
> +        .params     = "",
> +        .help       = "show the machine boards",
> +        .user_print = monitor_user_noop,
> +        .mhandler.info_new = do_info_machines,
> +    },
> +    {
>           .name       = "commands",
>           .args_type  = "",
>           .params     = "",
> diff --git a/vl.c b/vl.c
> index 0b38d62..8043fac 100644
> --- a/vl.c
> +++ b/vl.c
> @@ -1537,6 +1537,76 @@ static QEMUMachine *find_default_machine(void)
>       return NULL;
>   }
>
> +
> +/**
> + * do_info_machines(): Show machine boards
> + *
> + * Returns a QList object listing all machine boards
> + * available with this QEMU target. Each element in
> + * the list is a QDict object containing the following
> + * keys
> + *
> + *  - "name": short name for the machine board
> + *  - "description": long description of the board
> + *  - "alias": name of an alias
> + *
> + * Example:
> + *
> + *  [
> + *     {
> + *       "name": "pc-0.13",
> + *        "description": "Standard PC",
> + *        "default": 0
> + *     },
> + *     {
> + *       "name": "pc",
> + *       "description": "Standard PC",
> + *       "canonical": "pc-0.13",
> + *       "default": 1
> + *     },
> + *     {
> + *       "name": "pc-0.12",
> + *       "description": "Standard PC",
> + *       "default": 0
> + *     },
> + *     ....
> + *  ]
> + *
> + */
>    

My only suggestion would be to:

{ 'default-machine': 'pc',
    'machines': [{
      'name': 'pc',
      'description': 'Standard PC',
    },...]
}

I'd drop 'canonical' too.  Aliasing is an implementation detail and 
should not be exposed via the ABI.

Regards,

Anthony Liguori