rigtop_core/linux/
mod.rs

1//! Linux-specific readers for `/sys` and `/proc`.
2//!
3//! These cover what `sysinfo` does not expose: hwmon sensors, RAPL energy
4//! counters, per-device disk I/O, btrfs and mdadm state.
5//!
6//! Every reader takes its root directories from [`SysRoots`] instead of
7//! hard-coding `/sys` and `/proc`, so tests can point them at a fixture tree.
8
9pub mod battery;
10pub mod btrfs;
11pub mod diskstats;
12pub mod drm;
13pub mod hwmon;
14pub mod mdstat;
15pub mod meminfo;
16pub mod mounts;
17pub mod net;
18pub mod procstat;
19pub mod rapl;
20
21use std::fs;
22use std::path::{Path, PathBuf};
23
24/// Root directories of the kernel pseudo filesystems.
25#[derive(Debug, Clone)]
26pub struct SysRoots {
27    /// Normally `/sys`.
28    pub sys: PathBuf,
29    /// Normally `/proc`.
30    pub proc: PathBuf,
31}
32
33impl Default for SysRoots {
34    fn default() -> Self {
35        Self {
36            sys: PathBuf::from("/sys"),
37            proc: PathBuf::from("/proc"),
38        }
39    }
40}
41
42/// Reads a sysfs attribute and trims the trailing newline.
43///
44/// Returns `None` on any error: sysfs attributes may disappear at any time
45/// (hot-unplug) or be unreadable without root, and callers treat both as
46/// "not available".
47pub(crate) fn read_trimmed(path: &Path) -> Option<String> {
48    fs::read_to_string(path).ok().map(|s| s.trim().to_owned())
49}
50
51/// Reads a sysfs attribute holding a single unsigned integer.
52pub(crate) fn read_u64(path: &Path) -> Option<u64> {
53    read_trimmed(path)?.parse().ok()
54}
55
56/// Reads a sysfs attribute holding a single signed integer.
57pub(crate) fn read_i64(path: &Path) -> Option<i64> {
58    read_trimmed(path)?.parse().ok()
59}
60
61/// Returns the file names in `dir`, sorted, or an empty list if it cannot be read.
62pub(crate) fn sorted_entries(dir: &Path) -> Vec<String> {
63    let mut names: Vec<String> = match fs::read_dir(dir) {
64        Ok(entries) => entries
65            .filter_map(|e| e.ok())
66            .filter_map(|e| e.file_name().into_string().ok())
67            .collect(),
68        Err(_) => Vec::new(),
69    };
70    names.sort_by(|a, b| natural_cmp(a, b));
71    names
72}
73
74/// Compares strings so that embedded numbers sort numerically
75/// (`hwmon2` < `hwmon10`, `fan2` < `fan10`).
76pub(crate) fn natural_cmp(a: &str, b: &str) -> std::cmp::Ordering {
77    // Split into (non-digit prefix, trailing number). Kernel object names
78    // ("hwmon10", "nvme2", "md127") only carry a number at the end.
79    fn split(s: &str) -> (&str, Option<u64>) {
80        let digits_start = s
81            .char_indices()
82            .rev()
83            .take_while(|(_, c)| c.is_ascii_digit())
84            .last()
85            .map(|(i, _)| i)
86            .unwrap_or(s.len());
87        let (prefix, digits) = s.split_at(digits_start);
88        (prefix, digits.parse().ok())
89    }
90    let (pa, na) = split(a);
91    let (pb, nb) = split(b);
92    pa.cmp(pb).then(na.cmp(&nb)).then_with(|| a.cmp(b))
93}
94
95#[cfg(test)]
96pub(crate) mod testutil {
97    //! Helpers to build fake sysfs/procfs trees in a temporary directory.
98
99    use std::fs;
100    use std::path::Path;
101
102    /// Writes `content` to `root/rel`, creating parent directories.
103    pub fn write(root: &Path, rel: &str, content: &str) {
104        let path = root.join(rel);
105        fs::create_dir_all(path.parent().unwrap()).unwrap();
106        fs::write(path, content).unwrap();
107    }
108
109    /// Creates a symlink at `root/rel` pointing to `target` (absolute or relative).
110    pub fn symlink(root: &Path, rel: &str, target: &Path) {
111        let path = root.join(rel);
112        fs::create_dir_all(path.parent().unwrap()).unwrap();
113        std::os::unix::fs::symlink(target, path).unwrap();
114    }
115}
116
117#[cfg(test)]
118mod tests {
119    use super::natural_cmp;
120
121    #[test]
122    fn natural_order_sorts_numbers_numerically() {
123        let mut names = vec!["hwmon10", "hwmon2", "hwmon1", "fan"];
124        names.sort_by(|a, b| natural_cmp(a, b));
125        assert_eq!(names, vec!["fan", "hwmon1", "hwmon2", "hwmon10"]);
126    }
127}
rigtop_core/linux/mod.rs

rigtop_core/linux/
mod.rs
