On Thu, Apr 30, 2015 at 04:46:37PM +0100, Daniel P. Berrange wrote:
> A QOM property can be parsed as enum using the visit_type_enum()
> helper method, but this forces callers to use the more complex
> generic object_property_add() method when registering it. It
> also requires that users of that object have access to the
> string map when they want to read the property value.
>
> This patch introduces a specialized object_property_add_enum()
> method which simplifies the use of enum properties, so the
> setters/getters directly get passed the int value.
>
> typedef enum {
> MYDEV_TYPE_FROG,
> MYDEV_TYPE_ALLIGATOR,
> MYDEV_TYPE_PLATYPUS,
>
> MYDEV_TYPE_LAST
> } MyDevType;
>
> Then provide a table of enum <-> string mappings
>
> static const char *const mydevtypemap[MYDEV_TYPE_LAST + 1] = {
> [MYDEV_TYPE_FROG] = "frog",
> [MYDEV_TYPE_ALLIGATOR] = "alligator",
> [MYDEV_TYPE_PLATYPUS] = "platypus",
> [MYDEV_TYPE_LAST] = NULL,
> };
>
> Assuming an object struct of
>
> typedef struct {
> Object parent;
> MyDevType devtype;
> ...other fields...
> } MyDev;
>
> The property can then be registered as follows:
>
> static int mydev_prop_get_devtype(Object *obj,
> Error **errp G_GNUC_UNUSED)
> {
> MyDev *dev = MYDEV(obj);
>
> return dev->devtype;
> }
>
> static void mydev_prop_set_devtype(Object *obj,
> int value,
> Error **errp G_GNUC_UNUSED)
> {
> MyDev *dev = MYDEV(obj);
>
> dev->endpoint = value;
> }
>
> object_property_add_enum(obj, "devtype",
> mydevtypemap, "MyDevType",
> mydev_prop_get_devtype,
> mydev_prop_set_devtype,
> NULL);
>
> Note there is no need to check the range of 'value' in
> the setter, because the string->enum conversion code will
> have already done that and reported an error as required.
>
> Signed-off-by: Daniel P. Berrange <berra...@redhat.com>
> ---
> include/qom/object.h | 19 ++++++++++++
> qom/object.c | 58 ++++++++++++++++++++++++++++++++++++
> tests/check-qom-proplist.c | 74
> ++++++++++++++++++++++++++++++++++++++++++++++
> 3 files changed, 151 insertions(+)
> diff --git a/tests/check-qom-proplist.c b/tests/check-qom-proplist.c
> index 9a02e4d..15f4933 100644
> --- a/tests/check-qom-proplist.c
> +++ b/tests/check-qom-proplist.c
> +static void test_dummy_badenum(void)
> +{
> + Error *err = NULL;
> + DummyObject *dobj = DUMMY_OBJECT(
> + object_new_propv(TYPE_DUMMY,
> + "/objects",
> + "dummy0",
> + &err,
> + "bv", "yes",
> + "sv", "Hiss hiss hiss",
> + "av", "yeti",
> + NULL));
Opps, this won't compile as I forgot to update the 2nd arg. Will
send a v3
Regards,
Daniel
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