Coverage Report

Created: 2024-09-08 06:35

/rust/registry/src/index.crates.io-6f17d22bba15001f/nix-0.28.0/src/sys/sysinfo.rs
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Source (jump to first uncovered line)
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use libc::{self, SI_LOAD_SHIFT};
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use std::time::Duration;
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use std::{cmp, mem};
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use crate::errno::Errno;
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use crate::Result;
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/// System info structure returned by `sysinfo`.
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#[derive(Copy, Clone, Debug, Eq, Hash, PartialEq)]
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#[repr(transparent)]
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pub struct SysInfo(libc::sysinfo);
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// The fields are c_ulong on 32-bit linux, u64 on 64-bit linux; x32's ulong is u32
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#[cfg(all(target_arch = "x86_64", target_pointer_width = "32"))]
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type mem_blocks_t = u64;
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#[cfg(not(all(target_arch = "x86_64", target_pointer_width = "32")))]
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type mem_blocks_t = libc::c_ulong;
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impl SysInfo {
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    /// Returns the load average tuple.
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    ///
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    /// The returned values represent the load average over time intervals of
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    /// 1, 5, and 15 minutes, respectively.
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0
    pub fn load_average(&self) -> (f64, f64, f64) {
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        (
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            self.0.loads[0] as f64 / (1 << SI_LOAD_SHIFT) as f64,
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            self.0.loads[1] as f64 / (1 << SI_LOAD_SHIFT) as f64,
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            self.0.loads[2] as f64 / (1 << SI_LOAD_SHIFT) as f64,
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        )
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    }
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    /// Returns the time since system boot.
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    // The cast is not unnecessary on all platforms.
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    #[allow(clippy::unnecessary_cast)]
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    pub fn uptime(&self) -> Duration {
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        // Truncate negative values to 0
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        Duration::from_secs(cmp::max(self.0.uptime, 0) as u64)
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    }
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    /// Current number of processes.
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    pub fn process_count(&self) -> u16 {
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        self.0.procs
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0
    }
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    /// Returns the amount of swap memory in Bytes.
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    pub fn swap_total(&self) -> u64 {
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        self.scale_mem(self.0.totalswap)
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    }
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    /// Returns the amount of unused swap memory in Bytes.
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    pub fn swap_free(&self) -> u64 {
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        self.scale_mem(self.0.freeswap)
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    }
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    /// Returns the total amount of installed RAM in Bytes.
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    pub fn ram_total(&self) -> u64 {
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        self.scale_mem(self.0.totalram)
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    }
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    /// Returns the amount of completely unused RAM in Bytes.
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    ///
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    /// "Unused" in this context means that the RAM in neither actively used by
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    /// programs, nor by the operating system as disk cache or buffer. It is
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    /// "wasted" RAM since it currently serves no purpose.
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    pub fn ram_unused(&self) -> u64 {
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        self.scale_mem(self.0.freeram)
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    }
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    // The cast is not unnecessary on all platforms.
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    #[allow(clippy::unnecessary_cast)]
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    fn scale_mem(&self, units: mem_blocks_t) -> u64 {
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        units as u64 * self.0.mem_unit as u64
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    }
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}
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/// Returns system information.
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///
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/// [See `sysinfo(2)`](https://man7.org/linux/man-pages/man2/sysinfo.2.html).
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pub fn sysinfo() -> Result<SysInfo> {
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    let mut info = mem::MaybeUninit::uninit();
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    let res = unsafe { libc::sysinfo(info.as_mut_ptr()) };
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    Errno::result(res).map(|_| unsafe { SysInfo(info.assume_init()) })
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}