In DEFINE_PROP_ARRAY, because we use a PropertyInfo (qdev_prop_arraylen)
which has a .set_default_value member we will set the field to a default
value. That default value will be zero, by the C rule that struct
initialization sets unmentioned members to zero if at least one member
is initialized. However it's clearer to state it explicitly.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
---
If my eyeball of the sources is correct, this is the only case we
have of a Property struct that uses a PropertyInfo with a non-NULL
.set_default_value but which doesn't explicitly set .defval.u.
---
include/hw/qdev-properties.h | 1 +
1 file changed, 1 insertion(+)
diff --git a/include/hw/qdev-properties.h b/include/hw/qdev-properties.h
index 0604c33..36d040c 100644
--- a/include/hw/qdev-properties.h
+++ b/include/hw/qdev-properties.h
@@ -110,6 +110,7 @@ extern PropertyInfo qdev_prop_arraylen;
_arrayfield, _arrayprop, _arraytype) { \
.name = (PROP_ARRAY_LEN_PREFIX _name), \
.info = &(qdev_prop_arraylen), \
+ .defval.u = 0, \
.offset = offsetof(_state, _field) \
+ type_check(uint32_t, typeof_field(_state, _field)), \
.arrayinfo = &(_arrayprop), \
--
2.7.4
----- Original Message -----
> In DEFINE_PROP_ARRAY, because we use a PropertyInfo (qdev_prop_arraylen)
> which has a .set_default_value member we will set the field to a default
> value. That default value will be zero, by the C rule that struct
> initialization sets unmentioned members to zero if at least one member
> is initialized. However it's clearer to state it explicitly.
>
> Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
> ---
> If my eyeball of the sources is correct, this is the only case we
> have of a Property struct that uses a PropertyInfo with a non-NULL
> .set_default_value but which doesn't explicitly set .defval.u.
> ---
> include/hw/qdev-properties.h | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/include/hw/qdev-properties.h b/include/hw/qdev-properties.h
> index 0604c33..36d040c 100644
> --- a/include/hw/qdev-properties.h
> +++ b/include/hw/qdev-properties.h
> @@ -110,6 +110,7 @@ extern PropertyInfo qdev_prop_arraylen;
> _arrayfield, _arrayprop, _arraytype) { \
> .name = (PROP_ARRAY_LEN_PREFIX _name), \
> .info = &(qdev_prop_arraylen), \
> + .defval.u = 0, \
> .offset = offsetof(_state, _field) \
> + type_check(uint32_t, typeof_field(_state, _field)), \
> .arrayinfo = &(_arrayprop), \
> --
> 2.7.4
>
>
Peter Maydell <peter.maydell@linaro.org> writes:
> In DEFINE_PROP_ARRAY, because we use a PropertyInfo (qdev_prop_arraylen)
> which has a .set_default_value member we will set the field to a default
> value. That default value will be zero, by the C rule that struct
> initialization sets unmentioned members to zero if at least one member
> is initialized. However it's clearer to state it explicitly.
>
> Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
> ---
> If my eyeball of the sources is correct, this is the only case we
> have of a Property struct that uses a PropertyInfo with a non-NULL
> .set_default_value but which doesn't explicitly set .defval.u.
> ---
> include/hw/qdev-properties.h | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/include/hw/qdev-properties.h b/include/hw/qdev-properties.h
> index 0604c33..36d040c 100644
> --- a/include/hw/qdev-properties.h
> +++ b/include/hw/qdev-properties.h
> @@ -110,6 +110,7 @@ extern PropertyInfo qdev_prop_arraylen;
> _arrayfield, _arrayprop, _arraytype) { \
> .name = (PROP_ARRAY_LEN_PREFIX _name), \
> .info = &(qdev_prop_arraylen), \
> + .defval.u = 0, \
> .offset = offsetof(_state, _field) \
> + type_check(uint32_t, typeof_field(_state, _field)), \
> .arrayinfo = &(_arrayprop), \
Hmm.
.info and .defval apply to the array *length*.
.info.set_default_value() is set_default_uint(), which uses .defval.u.
Setting it here is correct.
The array *elements* are described by .arrayinfo. There is no
.arraydefval, but that's okay, because .arrayinfo.set_default_value()
doesn't get called. Correct?
On 13 July 2017 at 15:11, Markus Armbruster <armbru@redhat.com> wrote:
> Peter Maydell <peter.maydell@linaro.org> writes:
>
>> In DEFINE_PROP_ARRAY, because we use a PropertyInfo (qdev_prop_arraylen)
>> which has a .set_default_value member we will set the field to a default
>> value. That default value will be zero, by the C rule that struct
>> initialization sets unmentioned members to zero if at least one member
>> is initialized. However it's clearer to state it explicitly.
>>
>> Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
>> ---
>> If my eyeball of the sources is correct, this is the only case we
>> have of a Property struct that uses a PropertyInfo with a non-NULL
>> .set_default_value but which doesn't explicitly set .defval.u.
>> ---
>> include/hw/qdev-properties.h | 1 +
>> 1 file changed, 1 insertion(+)
>>
>> diff --git a/include/hw/qdev-properties.h b/include/hw/qdev-properties.h
>> index 0604c33..36d040c 100644
>> --- a/include/hw/qdev-properties.h
>> +++ b/include/hw/qdev-properties.h
>> @@ -110,6 +110,7 @@ extern PropertyInfo qdev_prop_arraylen;
>> _arrayfield, _arrayprop, _arraytype) { \
>> .name = (PROP_ARRAY_LEN_PREFIX _name), \
>> .info = &(qdev_prop_arraylen), \
>> + .defval.u = 0, \
>> .offset = offsetof(_state, _field) \
>> + type_check(uint32_t, typeof_field(_state, _field)), \
>> .arrayinfo = &(_arrayprop), \
>
> Hmm.
>
> .info and .defval apply to the array *length*.
> .info.set_default_value() is set_default_uint(), which uses .defval.u.
> Setting it here is correct.
>
> The array *elements* are described by .arrayinfo. There is no
> .arraydefval, but that's okay, because .arrayinfo.set_default_value()
> doesn't get called. Correct?
Correct. (There's no way to specify a default value for array properties.)
thanks
-- PMM
Peter Maydell <peter.maydell@linaro.org> writes:
> On 13 July 2017 at 15:11, Markus Armbruster <armbru@redhat.com> wrote:
>> Peter Maydell <peter.maydell@linaro.org> writes:
>>
>>> In DEFINE_PROP_ARRAY, because we use a PropertyInfo (qdev_prop_arraylen)
>>> which has a .set_default_value member we will set the field to a default
>>> value. That default value will be zero, by the C rule that struct
>>> initialization sets unmentioned members to zero if at least one member
>>> is initialized. However it's clearer to state it explicitly.
>>>
>>> Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
>>> ---
>>> If my eyeball of the sources is correct, this is the only case we
>>> have of a Property struct that uses a PropertyInfo with a non-NULL
>>> .set_default_value but which doesn't explicitly set .defval.u.
>>> ---
>>> include/hw/qdev-properties.h | 1 +
>>> 1 file changed, 1 insertion(+)
>>>
>>> diff --git a/include/hw/qdev-properties.h b/include/hw/qdev-properties.h
>>> index 0604c33..36d040c 100644
>>> --- a/include/hw/qdev-properties.h
>>> +++ b/include/hw/qdev-properties.h
>>> @@ -110,6 +110,7 @@ extern PropertyInfo qdev_prop_arraylen;
>>> _arrayfield, _arrayprop, _arraytype) { \
>>> .name = (PROP_ARRAY_LEN_PREFIX _name), \
>>> .info = &(qdev_prop_arraylen), \
>>> + .defval.u = 0, \
>>> .offset = offsetof(_state, _field) \
>>> + type_check(uint32_t, typeof_field(_state, _field)), \
>>> .arrayinfo = &(_arrayprop), \
>>
>> Hmm.
>>
>> .info and .defval apply to the array *length*.
>> .info.set_default_value() is set_default_uint(), which uses .defval.u.
>> Setting it here is correct.
>>
>> The array *elements* are described by .arrayinfo. There is no
>> .arraydefval, but that's okay, because .arrayinfo.set_default_value()
>> doesn't get called. Correct?
>
> Correct. (There's no way to specify a default value for array properties.)
Thanks!
Reviewed-by: Markus Armbruster <armbru@redhat.com>
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