Re: [Qemu-devel] [PATCH qemu repost] qmp: Add qom-list-properties to list QOM object properties

[Paolo Bonzini]

On 22/02/2018 06:00, Alexey Kardashevskiy wrote:
> There is already 'device-list-properties' which does most of the job,
> however it does not handle everything returned by qom-list-types such
> as machines as they inherit directly from TYPE_OBJECT and not TYPE_DEVICE.
> 
> This adds a new qom-list-properties command which prints properties
> of a specific class and its instance. It is pretty much a simplified copy
> of the device-list-properties handler.
> 
> Since it creates an object instance, device properties should appear
> in the output as they are copied to QOM properties at the instance_init
> hook.
> 
> Signed-off-by: Alexey Kardashevskiy <address@hidden>
> ---
> 
> This is a simple rebase on top of the current upstream.
> 
> 
> ---
>  qapi-schema.json | 29 +++++++++++++++++++++++++++++
>  qmp.c            | 52 ++++++++++++++++++++++++++++++++++++++++++++++++++++
>  2 files changed, 81 insertions(+)
> 
> diff --git a/qapi-schema.json b/qapi-schema.json
> index 0262b9f..fa5f189 100644
> --- a/qapi-schema.json
> +++ b/qapi-schema.json
> @@ -1455,6 +1455,35 @@
>    'returns': [ 'DevicePropertyInfo' ] }
>  
>  ##
> +# @QOMPropertyInfo:
> +#
> +# Information about object properties.
> +#
> +# @name: the name of the property
> +# @type: the typename of the property
> +# @description: if specified, the description of the property.
> +#
> +# Since: 2.12
> +##
> +{ 'struct': 'QOMPropertyInfo',
> +  'data': { 'name': 'str', 'type': 'str', '*description': 'str' } }
> +
> +##
> +# @qom-list-properties:
> +#
> +# List properties associated with a QOM object.
> +#
> +# @typename: the type name of an object
> +#
> +# Returns: a list of QOMPropertyInfo describing object properties
> +#
> +# Since: 2.12
> +##
> +{ 'command': 'qom-list-properties',
> +  'data': { 'typename': 'str'},
> +  'returns': [ 'QOMPropertyInfo' ] }
> +
> +##
>  # @xen-set-global-dirty-log:
>  #
>  # Enable or disable the global dirty log mode.
> diff --git a/qmp.c b/qmp.c
> index 793f6f3..f2d4781 100644
> --- a/qmp.c
> +++ b/qmp.c
> @@ -576,6 +576,58 @@ DevicePropertyInfoList *qmp_device_list_properties(const 
> char *typename,
>      return prop_list;
>  }
>  
> +QOMPropertyInfoList *qmp_qom_list_properties(const char *typename,
> +                                             Error **errp)
> +{
> +    ObjectClass *klass;
> +    Object *obj;
> +    ObjectProperty *prop;
> +    ObjectPropertyIterator iter;
> +    QOMPropertyInfoList *prop_list = NULL;
> +
> +    klass = object_class_by_name(typename);
> +    if (klass == NULL) {
> +        error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
> +                  "Class '%s' not found", typename);
> +        return NULL;
> +    }
> +
> +    klass = object_class_dynamic_cast(klass, TYPE_OBJECT);
> +    if (klass == NULL) {
> +        error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "typename", 
> TYPE_OBJECT);
> +        return NULL;
> +    }
> +
> +    if (object_class_is_abstract(klass)) {
> +        error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "typename",
> +                   "non-abstract class");

This sucks, it would be nice to enumerate properties on base classes. We
could list class properties only.  However, it can be improved later.

Queued, thanks.

Paolo

> +        return NULL;
> +    }
> +
> +    obj = object_new(typename);
> +
> +    object_property_iter_init(&iter, obj);
> +    while ((prop = object_property_iter_next(&iter))) {
> +        QOMPropertyInfo *info;
> +        QOMPropertyInfoList *entry;
> +
> +        info = g_malloc0(sizeof(*info));
> +        info->name = g_strdup(prop->name);
> +        info->type = g_strdup(prop->type);
> +        info->has_description = !!prop->description;
> +        info->description = g_strdup(prop->description);
> +
> +        entry = g_malloc0(sizeof(*entry));
> +        entry->value = info;
> +        entry->next = prop_list;
> +        prop_list = entry;
> +    }
> +
> +    object_unref(obj);
> +
> +    return prop_list;
> +}
> +
>  CpuDefinitionInfoList *qmp_query_cpu_definitions(Error **errp)
>  {
>      return arch_query_cpu_definitions(errp);
>