Re: [Qemu-devel] [PATCH 0/3] Fix confused output for alias properties

[Gonglei (Arei)]

> -----Original Message-----
> From: Paolo Bonzini [mailto:address@hidden On Behalf Of Paolo
> Bonzini
> Sent: Monday, September 22, 2014 8:07 PM
> To: Gonglei (Arei); Michael S. Tsirkin
> Cc: address@hidden; Huangweidong (C); address@hidden; Huangpeng
> (Peter); address@hidden; address@hidden;
> address@hidden
> Subject: Re: [PATCH 0/3] Fix confused output for alias properties
> 
> Il 22/09/2014 13:22, Gonglei (Arei) ha scritto:
> > > This doesn't change the fact that ObjectProperty is a generic struct,
> > > and adding alias-specific fields there is wrong.
> >
> > OK, Maybe I should find other ways to attach this purpose and
> > avoid layering violation. Thanks!
> 
> Unfortunately I cannot think of any.
> 

What about this below way? Thanks!

(I don't add alias-sepecific filed into ObjectProperty
struct, just add a bool property. )

diff --git a/include/qom/object.h b/include/qom/object.h
index 8a05a81..8b8ded5 100644
--- a/include/qom/object.h
+++ b/include/qom/object.h
@@ -334,6 +334,11 @@ typedef void (ObjectPropertyRelease)(Object *obj,
                                      const char *name,
                                      void *opaque);

+typedef struct {
+    Object *target_obj;
+    const char *target_name;
+} AliasProperty;
+
 typedef struct ObjectProperty
 {
     gchar *name;
@@ -344,6 +349,8 @@ typedef struct ObjectProperty
     ObjectPropertyRelease *release;
     void *opaque;

+    bool is_alias;
+
     QTAILQ_ENTRY(ObjectProperty) node;
 } ObjectProperty;

diff --git a/qom/object.c b/qom/object.c
index a8c3065..0b4e402 100644
--- a/qom/object.c
+++ b/qom/object.c
@@ -1590,11 +1590,6 @@ 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)
 {
@@ -1663,6 +1658,7 @@ void object_property_add_alias(Object *obj, const char 
*name,
         goto out;
     }
     op->resolve = property_resolve_alias;
+    op->is_alias = true;

 out:
     g_free(prop_type);
-- 
1.7.12.4


> We could add a description field to ObjectProperty, and replace
> legacy_name with a description.  The output then would be
> 
> virtio-blk.drive=str (drive)
> 
> That's a bit hackish, but perhaps it would be good enough for mst and
> Markus?
> 
> Paolo

Best regards,
-Gonglei