lib/rust_support/init.rs

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 * a copy of this software and associated documentation files
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 *
 * The above copyright notice and this permission notice shall be
 * included in all copies or substantial portions of the Software.
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use crate::sys::uint;
use core::ffi::c_char;

pub use crate::sys::lk_init_flags;
pub use crate::sys::lk_init_level;
pub use crate::sys::lk_init_struct;

// SAFETY: lk_init_struct does not use interior mutability.
unsafe impl Sync for lk_init_struct {}

// lk_init_level constants have large gaps between them and some modules
// add or subtract from these constants to indicate that it wants to run
// right before or after other init hooks at a given level. Add add and sub
// functions to lk_init_level to allow this for rust init hooks as well.
impl lk_init_level {
    pub const fn add(mut self, rhs: uint) -> Self {
        self.0 += rhs;
        self
    }
    pub const fn sub(mut self, rhs: uint) -> Self {
        self.0 -= rhs;
        self
    }
}

impl lk_init_struct {
    pub const fn new(
        level: lk_init_level,
        flags: lk_init_flags,
        hook: unsafe extern "C" fn(uint),
        name: *const c_char,
    ) -> Self {
        lk_init_struct { level: level.0, flags: flags.0, hook: Option::Some(hook), name }
    }
}

#[macro_export]
macro_rules! LK_INIT_HOOK_FLAGS {
    ($name:ident, $hook:expr, $level:expr, $flags:expr) => {
        #[link_section = ".lk_init"]
        #[no_mangle]
        #[used]
        static $name: $crate::init::lk_init_struct = $crate::init::lk_init_struct::new(
            $level,
            $flags,
            $hook,
            (concat!(stringify!($name), "\0").as_bytes()).as_ptr().cast(),
        );
    };
}

#[macro_export]
macro_rules! LK_INIT_HOOK {
    ($name:ident, $hook:expr, $level:expr) => {
        $crate::LK_INIT_HOOK_FLAGS!(
            $name,
            $hook,
            $level,
            $crate::init::lk_init_flags::LK_INIT_FLAG_PRIMARY_CPU
        );
    };
}