crates/windows-kernel-rs/src/intrin.rs


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use windows_kernel_sys::intrin::{read_msr_safe, write_msr_safe};

use crate::error::{Error, IntoResult};

/// Attempts to read the given model-specific register. Accessing an invalid
/// model-specific register would normally result in a CPU exception. This
/// function uses Structured Exception Handling (SEH) to safely catch CPU
/// exceptions and to turn them into an [`Error`]. This prevents a hang.
pub fn read_msr(register: u32) -> Result<u64, Error> {
  let mut value = 0;

  unsafe { read_msr_safe(register, &mut value) }.into_result()?;

  Ok(value)
}

/// Attempts to write the given value to the given model-specific register.
/// Accessing an invalid model-specific register would normally result in a CPU
/// exception. This function uses Structured Handling (SEH) to safely catch CPU
/// exceptions and to turn them into an [`Error`]. This prevents a hang.
pub fn write_msr(register: u32, value: u64) -> Result<(), Error> {
  unsafe { write_msr_safe(register, value) }.into_result()?;

  Ok(())
}