procfs_core/
uptime.rs

1use crate::{expect, ProcResult};
2
3use std::io::Read;
4use std::str::FromStr;
5use std::time::Duration;
6
7/// The uptime of the system, based on the `/proc/uptime` file.
8#[derive(Debug, Clone)]
9#[non_exhaustive]
10pub struct Uptime {
11    /// The uptime of the system (including time spent in suspend).
12    pub uptime: f64,
13
14    /// The sum of how much time each core has spent idle.
15    pub idle: f64,
16}
17
18impl super::FromRead for Uptime {
19    fn from_read<R: Read>(mut r: R) -> ProcResult<Self> {
20        let mut buf = Vec::with_capacity(128);
21        r.read_to_end(&mut buf)?;
22
23        let line = String::from_utf8_lossy(&buf);
24        let buf = line.trim();
25
26        let mut s = buf.split(' ');
27        let uptime = expect!(f64::from_str(expect!(s.next())));
28        let idle = expect!(f64::from_str(expect!(s.next())));
29
30        Ok(Uptime { uptime, idle })
31    }
32}
33
34impl Uptime {
35    /// The uptime of the system (including time spent in suspend).
36    pub fn uptime_duration(&self) -> Duration {
37        let secs = self.uptime.trunc() as u64;
38        let csecs = (self.uptime.fract() * 100.0).round() as u32;
39        let nsecs = csecs * 10_000_000;
40
41        Duration::new(secs, nsecs)
42    }
43
44    /// The sum of how much time each core has spent idle.
45    pub fn idle_duration(&self) -> Duration {
46        let secs = self.idle.trunc() as u64;
47        let csecs = (self.idle.fract() * 100.0).round() as u32;
48        let nsecs = csecs * 10_000_000;
49
50        Duration::new(secs, nsecs)
51    }
52}
53
54#[cfg(test)]
55mod tests {
56    use super::*;
57    use crate::FromRead;
58    use std::io::Cursor;
59
60    #[test]
61    fn test_uptime() {
62        let reader = Cursor::new(b"2578790.61 1999230.98\n");
63        let uptime = Uptime::from_read(reader).unwrap();
64
65        assert_eq!(uptime.uptime_duration(), Duration::new(2578790, 610_000_000));
66        assert_eq!(uptime.idle_duration(), Duration::new(1999230, 980_000_000));
67    }
68}
procfs_core/uptime.rs

procfs_core/
uptime.rs
