Coverage Report

Created: 2025-07-14 07:05

/rust/registry/src/index.crates.io-6f17d22bba15001f/x86_64-0.14.13/src/lib.rs
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//! This crate provides x86_64 specific functions and data structures,
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//! and access to various system registers.
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#![cfg_attr(not(test), no_std)]
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#![cfg_attr(feature = "const_fn", feature(const_mut_refs))] // GDT add_entry()
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#![cfg_attr(feature = "abi_x86_interrupt", feature(abi_x86_interrupt))]
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#![cfg_attr(feature = "step_trait", feature(step_trait))]
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#![cfg_attr(feature = "doc_auto_cfg", feature(doc_auto_cfg))]
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#![warn(missing_docs)]
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#![deny(missing_debug_implementations)]
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#![deny(unsafe_op_in_unsafe_fn)]
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pub use crate::addr::{align_down, align_up, PhysAddr, VirtAddr};
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pub mod addr;
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pub mod instructions;
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pub mod registers;
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pub mod structures;
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/// Represents a protection ring level.
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#[derive(Debug, Copy, Clone, PartialEq, Eq, Hash)]
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#[repr(u8)]
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pub enum PrivilegeLevel {
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    /// Privilege-level 0 (most privilege): This level is used by critical system-software
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    /// components that require direct access to, and control over, all processor and system
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    /// resources. This can include BIOS, memory-management functions, and interrupt handlers.
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    Ring0 = 0,
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    /// Privilege-level 1 (moderate privilege): This level is used by less-critical system-
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    /// software services that can access and control a limited scope of processor and system
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    /// resources. Software running at these privilege levels might include some device drivers
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    /// and library routines. The actual privileges of this level are defined by the
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    /// operating system.
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    Ring1 = 1,
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    /// Privilege-level 2 (moderate privilege): Like level 1, this level is used by
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    /// less-critical system-software services that can access and control a limited scope of
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    /// processor and system resources. The actual privileges of this level are defined by the
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    /// operating system.
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    Ring2 = 2,
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    /// Privilege-level 3 (least privilege): This level is used by application software.
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    /// Software running at privilege-level 3 is normally prevented from directly accessing
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    /// most processor and system resources. Instead, applications request access to the
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    /// protected processor and system resources by calling more-privileged service routines
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    /// to perform the accesses.
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    Ring3 = 3,
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}
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impl PrivilegeLevel {
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    /// Creates a `PrivilegeLevel` from a numeric value. The value must be in the range 0..4.
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    ///
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    /// This function panics if the passed value is >3.
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    #[inline]
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    pub const fn from_u16(value: u16) -> PrivilegeLevel {
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        match value {
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            0 => PrivilegeLevel::Ring0,
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            1 => PrivilegeLevel::Ring1,
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            2 => PrivilegeLevel::Ring2,
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            3 => PrivilegeLevel::Ring3,
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            _ => panic!("invalid privilege level"),
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        }
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    }
Unexecuted instantiation: <x86_64::PrivilegeLevel>::from_u16
Unexecuted instantiation: <x86_64::PrivilegeLevel>::from_u16
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}