Re: [Qemu-devel] [PATCH] qom, qmp, hmp, qapi: create qom-type-list for class properties

["Daniel P. Berrange" <berrange@redhat.com>]

On Wed, Jan 20, 2016 at 12:42:38PM +0300, Valentin Rakush wrote:
> This patch adds support for qom-type-list command that supposed to list object class properties. Will use this functionality further to implement x86_64 cpu properties.
> 
> Additionally object_class_property_iterator_init function is implemented for consistency.

Please line break your commit messages at approx 72 characters

> Signed-off-by: Valentin Rakush <valentin.rakush@gmail.com>
> Cc: Luiz Capitulino <lcapitulino@redhat.com>
> Cc: Eric Blake <eblake@redhat.com>
> Cc: Markus Armbruster <armbru@redhat.com>
> Cc: Andreas Färber <afaerber@suse.de>
> Cc: Daniel P. Berrange <berrange@redhat.com>
> ---
>  hmp.c                | 26 ++++++++++++++++++++++++++
>  hmp.h                |  1 +
>  include/qom/object.h | 31 +++++++++++++++++++++++++++++++
>  qapi-schema.json     | 19 +++++++++++++++++++
>  qmp-commands.hx      |  6 ++++++
>  qmp.c                | 29 +++++++++++++++++++++++++++++
>  qom/object.c         |  8 ++++++++
>  7 files changed, 120 insertions(+)
> 
> diff --git a/hmp.c b/hmp.c
> index 54f2620..64aa991 100644
> --- a/hmp.c
> +++ b/hmp.c
> @@ -2052,6 +2052,32 @@ void hmp_qom_list(Monitor *mon, const QDict *qdict)
>      hmp_handle_error(mon, &err);
>  }
>  
> +void hmp_qom_type_list(Monitor *mon, const QDict *qdict)
> +{
> +    const char *path = qdict_get_try_str(qdict, "path");
> +    ObjectPropertyInfoList *list;
> +    Error *err = NULL;
> +
> +    if (path == NULL) {
> +        monitor_printf(mon, "/\n");
> +        return;
> +    }
> +
> +    list = qmp_qom_type_list(path, &err);
> +    if (err == NULL) {
> +        ObjectPropertyInfoList *start = list;
> +        while (list != NULL) {
> +            ObjectPropertyInfo *value = list->value;
> +
> +            monitor_printf(mon, "%s (%s)\n",
> +                           value->name, value->type);
> +            list = list->next;
> +        }
> +        qapi_free_ObjectPropertyInfoList(start);
> +    }
> +    hmp_handle_error(mon, &err);
> +}
> +
>  void hmp_qom_set(Monitor *mon, const QDict *qdict)
>  {
>      const char *path = qdict_get_str(qdict, "path");
> diff --git a/hmp.h b/hmp.h
> index a8c5b5a..d81cd4c 100644
> --- a/hmp.h
> +++ b/hmp.h
> @@ -103,6 +103,7 @@ void hmp_object_del(Monitor *mon, const QDict *qdict);
>  void hmp_info_memdev(Monitor *mon, const QDict *qdict);
>  void hmp_info_memory_devices(Monitor *mon, const QDict *qdict);
>  void hmp_qom_list(Monitor *mon, const QDict *qdict);
> +void hmp_qom_type_list(Monitor *mon, const QDict *qdict);
>  void hmp_qom_set(Monitor *mon, const QDict *qdict);
>  void object_add_completion(ReadLineState *rs, int nb_args, const char *str);
>  void object_del_completion(ReadLineState *rs, int nb_args, const char *str);
> diff --git a/include/qom/object.h b/include/qom/object.h
> index d0dafe9..f8ca725 100644
> --- a/include/qom/object.h
> +++ b/include/qom/object.h
> @@ -1013,6 +1013,37 @@ void object_property_iter_init(ObjectPropertyIterator *iter,
>   */
>  ObjectProperty *object_property_iter_next(ObjectPropertyIterator *iter);
>  
> +/**
> + * object_class_property_iter_init:
> + * @klass: the klass to iter properties for
> + *
> + * Initializes an iterator for traversing all properties
> + * registered against a klass type and all parent classes.
> + *
> + * It is forbidden to modify the property list while iterating,
> + * whether removing or adding properties.
> + *
> + * NB For getting next property in the list the object related
> + * function object_property_iter_next is still used.
> + *
> + * Typical usage pattern would be
> + *
> + * <example>
> + *   <title>Using object class property iterators</title>
> + *   <programlisting>
> + *   ObjectProperty *prop;
> + *   ObjectPropertyIterator iter;
> + *
> + *   object_class property_iter_init(&iter, obj);
> + *   while ((prop = object_property_iter_next(&iter))) {
> + *     ... do something with prop ...
> + *   }
> + *   </programlisting>
> + * </example>
> + */
> +void object_class_property_iter_init(ObjectPropertyIterator *iter,
> +                               ObjectClass *klass);
> +
>  void object_unparent(Object *obj);
>  
>  /**
> diff --git a/qapi-schema.json b/qapi-schema.json
> index b3038b2..c50d24c 100644
> --- a/qapi-schema.json
> +++ b/qapi-schema.json
> @@ -4081,3 +4081,22 @@
>  ##
>  { 'enum': 'ReplayMode',
>    'data': [ 'none', 'record', 'play' ] }
> +
> +##
> +# @qom-type-list:

I realize you're following the pattern of 'qom-list' but that
in itself is a misleading name really.

So i'd suggest we call this 'qom-type-prop-list' to more
accurately describe what it is doing.

> +#
> +# This command will list any properties of a object class
> +# given a path in the object class model.
> +#
> +# @path: the path within the object class model. See @qom-list-types
> +#        to check available object class names.
> +#
> +# Returns: a list of @ObjectPropertyInfo that describe the properties of the
> +#          object class.
> +#
> +# Since: 2.6
> +##
> +{ 'command': 'qom-type-list',
> +  'data': { 'path': 'str' },

This should be called 'typename' really, as this is not
an object path.

> +  'returns': [ 'ObjectPropertyInfo' ] }
> +
> diff --git a/qmp-commands.hx b/qmp-commands.hx
> index db072a6..4e5dd48 100644
> --- a/qmp-commands.hx
> +++ b/qmp-commands.hx
> @@ -3789,6 +3789,12 @@ EQMP
>      },
>  
>      {
> +        .name       = "qom-type-list",
> +        .args_type  = "path:s",
> +        .mhandler.cmd_new = qmp_marshal_qom_type_list,
> +    },
> +
> +    {
>          .name       = "qom-set",
>  	.args_type  = "path:s,property:s,value:q",
>          .mhandler.cmd_new = qmp_marshal_qom_set,
> diff --git a/qmp.c b/qmp.c
> index 3ff6db7..86dd1f2 100644
> --- a/qmp.c
> +++ b/qmp.c
> @@ -448,6 +448,35 @@ ObjectTypeInfoList *qmp_qom_list_types(bool has_implements,
>      return ret;
>  }
>  
> +ObjectPropertyInfoList *qmp_qom_type_list(const char *path, Error **errp)

With my earlier change this will become s/path/typename/

> +{
> +    ObjectClass *klass;
> +    ObjectPropertyInfoList *props = NULL;
> +    ObjectProperty* prop;
> +    ObjectPropertyIterator iter;
> +
> +    klass = object_class_by_name(path);
> +    if (klass == NULL) {
> +        error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
> +                  "Object class '%s' not found", path);
> +        return NULL;
> +    }
> +
> +    object_class_property_iter_init(&iter, klass);
> +    while ((prop = object_property_iter_next(&iter))) {
> +        ObjectPropertyInfoList *entry = g_malloc0(sizeof(*entry));

This could be g_new0(ObjectPropertyInfoList, 1) instead
of using g_malloc + sizeof directly.

> +
> +        entry->value = g_malloc0(sizeof(ObjectPropertyInfo));
> +        entry->next = props;
> +        props = entry;
> +
> +        entry->value->name = g_strdup(prop->name);
> +        entry->value->type = g_strdup(prop->type);
> +    }
> +
> +    return props;
> +}
> +
>  /* Return a DevicePropertyInfo for a qdev property.
>   *
>   * If a qdev property with the given name does not exist, use the given default
> diff --git a/qom/object.c b/qom/object.c
> index 5ff97ab..a158076 100644
> --- a/qom/object.c
> +++ b/qom/object.c
> @@ -994,6 +994,14 @@ ObjectProperty *object_property_find(Object *obj, const char *name,
>      return NULL;
>  }
>  
> +void object_class_property_iter_init(ObjectPropertyIterator *iter,
> +                               ObjectClass *klass)

Vertically align the 'ObjectClass' with 'ObjectPropertyIterator'

> +{
> +    g_hash_table_iter_init(&iter->iter, klass->properties);
> +    iter->nextclass = object_class_get_parent(klass);
> +

Can kil this extra blank line

> +}
> +
>  void object_property_iter_init(ObjectPropertyIterator *iter,
>                                 Object *obj)
>  {

Overall the code looks good - just bikeshedding over some naming and
a few other minor points.

Regards,
Daniel
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