Message ID | 1402505369-12526-3-git-send-email-pbonzini@redhat.com |
---|---|
State | New |
Headers | show |
Am 11.06.2014 18:49, schrieb Paolo Bonzini: > From: Stefan Hajnoczi <stefanha@redhat.com> > > Sometimes an object needs to present a property which is actually on > another object, or it needs to provide an alias name for an existing > property. > > Examples: > a.foo -> b.foo > a.old_name -> a.new_name > > The new object_property_add_alias() API allows objects to alias a > property on the same object or another object. The source and target > names can be different. > > Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> > Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com> > Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> > --- > include/qom/object.h | 20 +++++++++++++++++ > qom/object.c | 61 ++++++++++++++++++++++++++++++++++++++++++++++++++++ > 2 files changed, 81 insertions(+) > > diff --git a/include/qom/object.h b/include/qom/object.h > index f8ab845..9c4a5a4 100644 > --- a/include/qom/object.h > +++ b/include/qom/object.h > @@ -1252,6 +1252,26 @@ void object_property_add_uint64_ptr(Object *obj, const char *name, > const uint64_t *v, Error **Errp); > > /** > + * object_property_add_alias: > + * @obj: the object to add a property to > + * @name: the name of the property > + * @target_obj: the object to forward property access to > + * @target_name: the name of the property on the forwarded object > + * @errp: if an error occurs, a pointer to an area to store the error > + * > + * Add an alias for a property on an object. This function will add a property > + * of the same type as the forwarded property. > + * > + * The caller must ensure that <code>@target_obj</code> stays alive as long as > + * this property exists. In the case of a child object or an alias on the same > + * object this will be the case. For aliases to other objects the caller is > + * responsible for taking a reference. > + */ > +void object_property_add_alias(Object *obj, const char *name, > + Object *target_obj, const char *target_name, > + Error **errp); > + > +/** > * object_child_foreach: > * @obj: the object whose children will be navigated > * @fn: the iterator function to be called > diff --git a/qom/object.c b/qom/object.c > index fcdd0da..e146ae5 100644 > --- a/qom/object.c > +++ b/qom/object.c > @@ -1532,6 +1532,67 @@ void object_property_add_uint64_ptr(Object *obj, const char *name, > NULL, NULL, (void *)v, errp); > } > > +typedef struct > +{ Coding Style > + Object *target_obj; > + const char *target_name; > +} AliasProperty; > + > +static void property_get_alias(Object *obj, struct Visitor *v, void *opaque, > + const char *name, Error **errp) > +{ > + AliasProperty *prop = opaque; > + > + object_property_get(prop->target_obj, v, prop->target_name, errp); > +} > + > +static void property_set_alias(Object *obj, struct Visitor *v, void *opaque, > + const char *name, Error **errp) > +{ > + AliasProperty *prop = opaque; > + > + object_property_set(prop->target_obj, v, prop->target_name, errp); > +} > + > +static Object *property_resolve_alias(Object *obj, void *opaque, > + const gchar *part) > +{ > + AliasProperty *prop = opaque; > + > + return object_resolve_path_component(prop->target_obj, prop->target_name); > +} > + > +static void property_release_alias(Object *obj, const char *name, void *opaque) > +{ > + AliasProperty *prop = opaque; > + > + g_free(prop); > +} > + > +void object_property_add_alias(Object *obj, const char *name, > + Object *target_obj, const char *target_name, > + Error **errp) > +{ > + AliasProperty *prop; > + ObjectProperty *target_prop; > + > + target_prop = object_property_find(target_obj, target_name, errp); > + if (!target_prop) { > + return; > + } > + > + prop = g_malloc(sizeof(*prop)); > + prop->target_obj = target_obj; > + prop->target_name = target_name; > + > + object_property_add_full(obj, name, target_prop->type, > + property_get_alias, > + property_set_alias, > + property_resolve_alias, > + property_release_alias, > + prop, errp); > +} > + > static void object_instance_init(Object *obj) > { > object_property_add_str(obj, "type", qdev_get_type, NULL, NULL); Otherwise looks good to me. Regards, Andreas
diff --git a/include/qom/object.h b/include/qom/object.h index f8ab845..9c4a5a4 100644 --- a/include/qom/object.h +++ b/include/qom/object.h @@ -1252,6 +1252,26 @@ void object_property_add_uint64_ptr(Object *obj, const char *name, const uint64_t *v, Error **Errp); /** + * object_property_add_alias: + * @obj: the object to add a property to + * @name: the name of the property + * @target_obj: the object to forward property access to + * @target_name: the name of the property on the forwarded object + * @errp: if an error occurs, a pointer to an area to store the error + * + * Add an alias for a property on an object. This function will add a property + * of the same type as the forwarded property. + * + * The caller must ensure that <code>@target_obj</code> stays alive as long as + * this property exists. In the case of a child object or an alias on the same + * object this will be the case. For aliases to other objects the caller is + * responsible for taking a reference. + */ +void object_property_add_alias(Object *obj, const char *name, + Object *target_obj, const char *target_name, + Error **errp); + +/** * object_child_foreach: * @obj: the object whose children will be navigated * @fn: the iterator function to be called diff --git a/qom/object.c b/qom/object.c index fcdd0da..e146ae5 100644 --- a/qom/object.c +++ b/qom/object.c @@ -1532,6 +1532,67 @@ void object_property_add_uint64_ptr(Object *obj, const char *name, NULL, NULL, (void *)v, errp); } +typedef struct +{ + Object *target_obj; + const char *target_name; +} AliasProperty; + +static void property_get_alias(Object *obj, struct Visitor *v, void *opaque, + const char *name, Error **errp) +{ + AliasProperty *prop = opaque; + + object_property_get(prop->target_obj, v, prop->target_name, errp); +} + +static void property_set_alias(Object *obj, struct Visitor *v, void *opaque, + const char *name, Error **errp) +{ + AliasProperty *prop = opaque; + + object_property_set(prop->target_obj, v, prop->target_name, errp); +} + +static Object *property_resolve_alias(Object *obj, void *opaque, + const gchar *part) +{ + AliasProperty *prop = opaque; + + return object_resolve_path_component(prop->target_obj, prop->target_name); +} + +static void property_release_alias(Object *obj, const char *name, void *opaque) +{ + AliasProperty *prop = opaque; + + g_free(prop); +} + +void object_property_add_alias(Object *obj, const char *name, + Object *target_obj, const char *target_name, + Error **errp) +{ + AliasProperty *prop; + ObjectProperty *target_prop; + + target_prop = object_property_find(target_obj, target_name, errp); + if (!target_prop) { + return; + } + + prop = g_malloc(sizeof(*prop)); + prop->target_obj = target_obj; + prop->target_name = target_name; + + object_property_add_full(obj, name, target_prop->type, + property_get_alias, + property_set_alias, + property_resolve_alias, + property_release_alias, + prop, errp); +} + static void object_instance_init(Object *obj) { object_property_add_str(obj, "type", qdev_get_type, NULL, NULL);