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#[derive(Clone, Copy, PartialEq, Eq, Debug)]
pub enum Capability {
    GetFramebuffer,
    EarlyLogging,
    ServiceProvider,
    ServiceUser,
    PciBusDriver,
}

pub const CAP_PADDING: u8 = 0x00;
pub const CAP_GET_FRAMEBUFFER: u8 = 0x01;
pub const CAP_EARLY_LOGGING: u8 = 0x02;
pub const CAP_SERVICE_PROVIDER: u8 = 0x03;
pub const CAP_SERVICE_USER: u8 = 0x04;
pub const CAP_PCI_BUS_DRIVER: u8 = 0x05;

/// `N` must be a multiple of 4, and padded with zeros, so the whole descriptor is aligned to a
/// 4-byte boundary.
///
/// This structure can be used to emit an ELF note section containing a list of capabilities. `N` must be a
/// multiple of 4 (padded with `CAP_PADDING`). You can define the capabilities of a task image like so:
/// ```
/// #[used]
/// #[link_section = ".caps"]
/// pub static mut CAPS: CapabilitiesRepr<4> = CapabilitiesRepr::new([CAP_EARLY_LOGGING,
/// CAP_GET_FRAMEBUFFER, CAP_PADDING, CAP_PADDING]);
/// ```
#[repr(C)]
pub struct CapabilitiesRepr<const N: usize> {
    name_size: u32,
    desc_size: u32,
    entry_type: u32,
    name: [u8; 8],
    desc: [u8; N],
}

impl<const N: usize> CapabilitiesRepr<{ N }> {
    pub const fn new(caps: [u8; N]) -> CapabilitiesRepr<{ N }> {
        CapabilitiesRepr {
            name_size: 6,
            desc_size: N as u32,
            entry_type: 0,
            name: [b'P', b'O', b'P', b'L', b'A', b'R', 0x00, 0x00],
            desc: caps,
        }
    }
}