core/platform/src/return_type.rs

/// `ReturnType` describes what value type the kernel has returned.
// ReturnType is not an enum so that it can be converted from a u32 for free.
#[derive(Clone, Copy, PartialEq, Eq)]
pub struct ReturnType {
    value: u32,
}

impl From<u32> for ReturnType {
    fn from(value: u32) -> ReturnType {
        ReturnType { value }
    }
}

impl From<ReturnType> for u32 {
    fn from(return_type: ReturnType) -> u32 {
        return_type.value
    }
}

pub const FAILURE: ReturnType = ReturnType { value: 0 };
pub const FAILURE_U32: ReturnType = ReturnType { value: 1 };
pub const FAILURE_2_U32: ReturnType = ReturnType { value: 2 };
pub const FAILURE_U64: ReturnType = ReturnType { value: 3 };
pub const SUCCESS: ReturnType = ReturnType { value: 128 };
pub const SUCCESS_U32: ReturnType = ReturnType { value: 129 };
pub const SUCCESS_2_U32: ReturnType = ReturnType { value: 130 };
pub const SUCCESS_U64: ReturnType = ReturnType { value: 131 };
pub const SUCCESS_3_U32: ReturnType = ReturnType { value: 132 };
pub const SUCCESS_U32_U64: ReturnType = ReturnType { value: 133 };