Re: [Qemu-ppc] [Qemu-devel] [PATCH 1/6] qom: macroify integer property helpers

[Peter Crosthwaite]

On Wed, Jul 2, 2014 at 7:49 AM, Alexander Graf <address@hidden> wrote:
> We have a bunch of nice helpers that allow us to easily register an integer
> field as QOM property. However, we have those duplicated for every integer
> size available.
>
> This is very cumbersome (and prone to bugs) to work with and extend, so let's
> strip out the only difference there is (the size) and generate the actual
> functions via a macro.
>
> Signed-off-by: Alexander Graf <address@hidden>
> ---
>  qom/object.c | 83 
> ++++++++++++++++++------------------------------------------
>  1 file changed, 24 insertions(+), 59 deletions(-)
>
> diff --git a/qom/object.c b/qom/object.c
> index 0e8267b..73cd717 100644
> --- a/qom/object.c
> +++ b/qom/object.c
> @@ -1507,65 +1507,30 @@ static char *qdev_get_type(Object *obj, Error **errp)
>      return g_strdup(object_get_typename(obj));
>  }
>
> -static void property_get_uint8_ptr(Object *obj, Visitor *v,
> -                                   void *opaque, const char *name,
> -                                   Error **errp)
> -{
> -    uint8_t value = *(uint8_t *)opaque;
> -    visit_type_uint8(v, &value, name, errp);
> -}
> -
> -static void property_get_uint16_ptr(Object *obj, Visitor *v,
> -                                   void *opaque, const char *name,
> -                                   Error **errp)
> -{
> -    uint16_t value = *(uint16_t *)opaque;
> -    visit_type_uint16(v, &value, name, errp);
> -}
> -
> -static void property_get_uint32_ptr(Object *obj, Visitor *v,
> -                                   void *opaque, const char *name,
> -                                   Error **errp)
> -{
> -    uint32_t value = *(uint32_t *)opaque;
> -    visit_type_uint32(v, &value, name, errp);
> -}
> -
> -static void property_get_uint64_ptr(Object *obj, Visitor *v,
> -                                   void *opaque, const char *name,
> -                                   Error **errp)
> -{
> -    uint64_t value = *(uint64_t *)opaque;
> -    visit_type_uint64(v, &value, name, errp);
> -}
> -
> -void object_property_add_uint8_ptr(Object *obj, const char *name,
> -                                   const uint8_t *v, Error **errp)
> -{
> -    object_property_add(obj, name, "uint8", property_get_uint8_ptr,
> -                        NULL, NULL, (void *)v, errp);
> -}
> -
> -void object_property_add_uint16_ptr(Object *obj, const char *name,
> -                                    const uint16_t *v, Error **errp)
> -{
> -    object_property_add(obj, name, "uint16", property_get_uint16_ptr,
> -                        NULL, NULL, (void *)v, errp);
> -}
> -
> -void object_property_add_uint32_ptr(Object *obj, const char *name,
> -                                    const uint32_t *v, Error **errp)
> -{
> -    object_property_add(obj, name, "uint32", property_get_uint32_ptr,
> -                        NULL, NULL, (void *)v, errp);
> -}
> -
> -void object_property_add_uint64_ptr(Object *obj, const char *name,
> -                                    const uint64_t *v, Error **errp)
> -{
> -    object_property_add(obj, name, "uint64", property_get_uint64_ptr,
> -                        NULL, NULL, (void *)v, errp);
> -}
> +#define DECLARE_INTEGER_VISITOR(size)                                        
>   \

macro needs a better name. DECLARE_PROP_SET_GET - something to make it
clear its about properties.

> +                                                                             
>   \
> +static void glue(glue(property_get_,size),_ptr)(Object *obj, Visitor *v,     
>   \
> +                                                void *opaque,                
>   \
> +                                                const char *name,            
>   \
> +                                                Error **errp)                
>   \
> +{                                                                            
>   \
> +    glue(size,_t) value = *(glue(size,_t) *)opaque;                          
>   \
> +    glue(visit_type_,size)(v, &value, name, errp);                           
>   \
> +}                                                                            
>   \
> +                                                                             
>   \
> +void glue(glue(object_property_add_,size),_ptr)(Object *obj, const char 
> *name, \
> +                                                const glue(size,_t) *v,      
>   \
> +                                                Error **errp)                
>   \
> +{                                                                            
>   \
> +    ObjectPropertyAccessor *get = glue(glue(property_get_,size),_ptr);       
>   \
> +    object_property_add(obj, name, stringify(size), get, NULL, NULL, (void 
> *)v,\
> +                        errp);                                               
>   \
> +}                                                                            
>   \
> +
> +DECLARE_INTEGER_VISITOR(uint8)
> +DECLARE_INTEGER_VISITOR(uint16)
> +DECLARE_INTEGER_VISITOR(uint32)
> +DECLARE_INTEGER_VISITOR(uint64)
>

Worth getting bool working this way too? Theres been a few times now
where I have wanted to object_property_add_bool_ptr. Perhaps:

#define DECLARE_PROP_SET_GET(name, type)

DECLARE_PROP_SET_GET(uint8, uint8_t)
DECLARE_PROP_SET_GET(uint16, uint16_t)
DECLARE_PROP_SET_GET(uint32, uint32_t)
DECLARE_PROP_SET_GET(uint64, uint64_t)
DECLARE_PROP_SET_GET(bool, bool)

Can actually add the bool one later in follow-up patch but just
thinking ahead to get the macro right for wider usage.

Regards,
Peter

>  typedef struct {
>      Object *target_obj;
> --
> 1.8.1.4
>
>