Re: [Qemu-devel] [PATCH 1/7] qmp: introduce device-list-properties command

[Luiz Capitulino <lcapitulino@redhat.com>]

On Fri, 27 Jul 2012 08:37:13 -0500
Anthony Liguori <aliguori@us.ibm.com> wrote:

> This can be used in conjunction with qom-list-types to determine the supported
> set of devices and their parameters.
> 
> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
> ---
>  qapi-schema.json |   28 ++++++++++++++++++++++++++++
>  qmp-commands.hx  |    7 +++++++
>  qmp.c            |   50 ++++++++++++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 85 insertions(+), 0 deletions(-)
> 
> diff --git a/qapi-schema.json b/qapi-schema.json
> index bc55ed2..015a84a 100644
> --- a/qapi-schema.json
> +++ b/qapi-schema.json
> @@ -1727,6 +1727,34 @@
>    'returns': [ 'ObjectTypeInfo' ] }
>  
>  ##
> +# @DevicePropertyInfo:
> +#
> +# Information about device properties.
> +#
> +# @name: the name of the property
> +# @type: the typename of the property
> +#
> +# Since: 1.2
> +##
> +{ 'type': 'DevicePropertyInfo',
> +  'data': { 'name': 'str', 'type': 'str' } }
> +
> +##
> +# @device-list-properties:
> +#
> +# List properties associated with a device.
> +#
> +# @typename: the type name of a device
> +#
> +# Returns: a list of DevicePropertyInfo describing a devices properties
> +#
> +# Since: 1.2
> +##
> +{ 'command': 'device-list-properties',
> +  'data': { 'typename': 'str'},
> +  'returns': [ 'DevicePropertyInfo' ] }

I find it a bit weird that the argument is called typename but everything else
refers to that same argument as a device.

Maybe we should rename this to device-type-list-properties, DeviceTypePropertyInfo
and typename to name.

But that's minor, I won't oppose to it as it's.

> +
> +##
>  # @migrate
>  #
>  # Migrates the current running guest to another Virtual Machine.
> diff --git a/qmp-commands.hx b/qmp-commands.hx
> index e3cf3c5..5c55528 100644
> --- a/qmp-commands.hx
> +++ b/qmp-commands.hx
> @@ -2215,3 +2215,10 @@ EQMP
>          .args_type  = "implements:s?,abstract:b?",
>          .mhandler.cmd_new = qmp_marshal_input_qom_list_types,
>      },
> +
> +    {
> +        .name       = "device-list-properties",
> +        .args_type  = "typename:s",
> +        .mhandler.cmd_new = qmp_marshal_input_device_list_properties,
> +    },
> +
> diff --git a/qmp.c b/qmp.c
> index fee9fb2..254a32f 100644
> --- a/qmp.c
> +++ b/qmp.c
> @@ -417,3 +417,53 @@ ObjectTypeInfoList *qmp_qom_list_types(bool has_implements,
>  
>      return ret;
>  }
> +
> +DevicePropertyInfoList *qmp_device_list_properties(const char *typename,
> +                                                   Error **errp)
> +{
> +    ObjectClass *klass;
> +    Property *prop;
> +    DevicePropertyInfoList *prop_list = NULL;
> +
> +    klass = object_class_by_name(typename);
> +    if (klass == NULL) {
> +        error_set(errp, QERR_DEVICE_NOT_FOUND, typename);
> +        return NULL;
> +    }
> +
> +    klass = object_class_dynamic_cast(klass, TYPE_DEVICE);
> +    if (klass == NULL) {
> +        error_set(errp, QERR_INVALID_PARAMETER_VALUE,
> +                  "name", TYPE_DEVICE);
> +        return NULL;
> +    }
> +
> +    do {
> +        for (prop = DEVICE_CLASS(klass)->props; prop && prop->name; prop++) {
> +            DevicePropertyInfoList *entry;
> +            DevicePropertyInfo *info;
> +
> +            /*
> +             * TODO Properties without a parser are just for dirty hacks.
> +             * qdev_prop_ptr is the only such PropertyInfo.  It's marked
> +             * for removal.  This conditional should be removed along with
> +             * it.
> +             */
> +            if (!prop->info->set) {
> +                continue;           /* no way to set it, don't show */
> +            }
> +
> +            info = g_malloc0(sizeof(*info));
> +            info->name = g_strdup(prop->name);
> +            info->type = g_strdup(prop->info->legacy_name ?: prop->info->name);
> +
> +            entry = g_malloc0(sizeof(*entry));
> +            entry->value = info;
> +            entry->next = prop_list;
> +            prop_list = entry;
> +        }
> +        klass = object_class_get_parent(klass);
> +    } while (klass != object_class_by_name(TYPE_DEVICE));
> +
> +    return prop_list;
> +}