heim-cpu 0.1.0-rc.1

use std::fmt;

use heim_common::prelude::*;
use heim_common::units::Time;

use crate::sys;

/// System CPU time.
///
/// ## Compatibility
///
/// For Linux additional information can be retrieved with [CpuTimeExt] extension trait.
///
/// [CpuTimeExt]: ./os/linux/trait.CpuTimeExt.html
#[derive(Clone)]
pub struct CpuTime(sys::CpuTime);

wrap!(CpuTime, sys::CpuTime);

impl CpuTime {
    /// Returns time spent by normal processes executing in user mode.
    ///
    /// ## Compatibility
    ///
    ///  * on Linux this also includes guest time
    pub fn user(&self) -> Time {
        self.as_ref().user()
    }

    /// Returns time spent by processes executing in kernel mode.
    pub fn system(&self) -> Time {
        self.as_ref().system()
    }

    /// Returns time spent doing nothing.
    pub fn idle(&self) -> Time {
        self.as_ref().idle()
    }
}

impl fmt::Debug for CpuTime {
    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
        f.debug_struct("CpuTime")
            .field("user", &self.user())
            .field("system", &self.system())
            .field("idle", &self.idle())
            .finish()
    }
}

/// Returns cumulative value of all [CPU times].
///
/// [CPU times]: struct.CpuTime.html
pub async fn time() -> Result<CpuTime> {
    sys::time().await.map(Into::into)
}

/// Returns a stream over the [CPU time] for each CPU core.
///
/// [CPU time]: struct.CpuTime.html
pub async fn times() -> Result<impl Stream<Item = Result<CpuTime>>> {
    let inner = sys::times().await?;

    Ok(inner.map_ok(Into::into))
}