On Tue, Dec 31, 2024 at 1:23 AM Paolo Bonzini <pbonzini@redhat.com> wrote:
>
> These are not type safe, but they're the best that can be done without
> const_refs_static.
>
> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
FWIW, I'll change these patch to support varrays in v2.
Paolo
> ---
> rust/qemu-api/src/vmstate.rs | 34 ++++++++++++++++++++++++++++++++++
> 1 file changed, 34 insertions(+)
>
> diff --git a/rust/qemu-api/src/vmstate.rs b/rust/qemu-api/src/vmstate.rs
> index b59a4b66339..e45c93587b2 100644
> --- a/rust/qemu-api/src/vmstate.rs
> +++ b/rust/qemu-api/src/vmstate.rs
> @@ -610,6 +610,40 @@ macro_rules! vmstate_array_of_pointer_to_struct {
> }};
> }
>
> +// FIXME: including the `vmsd` field in a `const` is not possible without
> +// the const_refs_static feature (stabilized in Rust 1.83.0). Without it,
> +// it is not possible to use VMS_STRUCT in a transparent manner using
> +// `vmstate_of!`. While VMSTATE_CLOCK can at least try to be type-safe,
> +// VMSTATE_STRUCT includes $type only for documentation purposes; it
> +// is checked against $field_name and $struct_name, but not against $vmsd
> +// which is what really would matter.
> +#[doc(alias = "VMSTATE_STRUCT")]
> +#[macro_export]
> +macro_rules! vmstate_struct {
> + ($field_name:ident, $struct_name:ty, $vmsd:expr, $type:ty) => {{
> + $crate::bindings::VMStateField {
> + name: ::core::concat!(::core::stringify!($field_name), "\0")
> + .as_bytes()
> + .as_ptr() as *const ::std::os::raw::c_char,
> + offset: {
> + $crate::assert_field_type!($struct_name, $field_name, $type);
> + $crate::offset_of!($struct_name, $field_name)
> + }
> + size: ::core::mem::size_of::<$type>(),
> + flags: $crate::bindings::VMStateFlags::VMS_STRUCT,
> + vmsd: unsafe { $vmsd },
> + ..$crate::zeroable::Zeroable::ZERO
> + }
> + }};
> +}
> +
> +#[macro_export]
> +macro_rules! vmstate_cell {
> + ($field_name:ident, $struct_name:ty, $vmsd:expr, $type:ty) => {
> + $crate::vmstate_struct!($field_name, $struct_name, $vmsd, $type)
> + };
> +}
> +
> #[doc(alias = "VMSTATE_CLOCK_V")]
> #[macro_export]
> macro_rules! vmstate_clock_v {
> --
> 2.47.1
>