sysinfo/unix/linux/
utils.rs

1// Take a look at the license at the top of the repository in the LICENSE file.
2
3#[cfg(any(feature = "disk", feature = "system"))]
4use std::fs::File;
5#[cfg(any(feature = "disk", feature = "system"))]
6use std::io::{self, Read, Seek};
7#[cfg(any(feature = "disk", feature = "system"))]
8use std::path::Path;
9
10#[cfg(feature = "system")]
11pub(crate) fn get_all_data_from_file(file: &mut File, size: usize) -> io::Result<Vec<u8>> {
12    let mut buf = Vec::with_capacity(size);
13    file.rewind()?;
14    file.read_to_end(&mut buf)?;
15    Ok(buf)
16}
17
18#[cfg(any(feature = "disk", feature = "system"))]
19pub(crate) fn get_all_utf8_data_from_file(file: &mut File, size: usize) -> io::Result<String> {
20    let mut buf = String::with_capacity(size);
21    file.rewind()?;
22    file.read_to_string(&mut buf)?;
23    Ok(buf)
24}
25
26#[cfg(any(feature = "disk", feature = "system"))]
27pub(crate) fn get_all_utf8_data<P: AsRef<Path>>(file_path: P, size: usize) -> io::Result<String> {
28    let mut file = File::open(file_path.as_ref())?;
29    get_all_utf8_data_from_file(&mut file, size)
30}
31
32/// This type is used in `retrieve_all_new_process_info` because we have a "parent" path and
33/// from it, we `pop`/`join` every time because it's more memory efficient than using `Path::join`.
34#[cfg(feature = "system")]
35pub(crate) struct PathHandler(std::path::PathBuf);
36
37#[cfg(feature = "system")]
38impl PathHandler {
39    pub(crate) fn new(path: &Path) -> Self {
40        // `path` is the "parent" for all paths which will follow so we add a fake element at
41        // the end since every `PathHandler::replace_and_join` call will first call `pop`
42        // internally.
43        Self(path.join("a"))
44    }
45
46    pub(crate) fn as_path(&self) -> &Path {
47        &self.0
48    }
49}
50
51#[cfg(feature = "system")]
52pub(crate) trait PathPush {
53    fn replace_and_join(&mut self, p: &str) -> &Path;
54}
55
56#[cfg(feature = "system")]
57impl PathPush for PathHandler {
58    fn replace_and_join(&mut self, p: &str) -> &Path {
59        self.0.pop();
60        self.0.push(p);
61        self.as_path()
62    }
63}
64
65// This implementation allows to skip one allocation that is done in `PathHandler`.
66#[cfg(feature = "system")]
67impl PathPush for std::path::PathBuf {
68    fn replace_and_join(&mut self, p: &str) -> &Path {
69        self.push(p);
70        self.as_path()
71    }
72}
73
74#[cfg(feature = "system")]
75pub(crate) fn to_u64(v: &[u8]) -> u64 {
76    let mut x = 0;
77
78    for c in v {
79        x *= 10;
80        x += u64::from(c - b'0');
81    }
82    x
83}
84
85/// Converts a path to a NUL-terminated `Vec<u8>` suitable for use with C functions.
86#[cfg(feature = "disk")]
87pub(crate) fn to_cpath(path: &std::path::Path) -> Vec<u8> {
88    use std::{ffi::OsStr, os::unix::ffi::OsStrExt};
89
90    let path_os: &OsStr = path.as_ref();
91    let mut cpath = path_os.as_bytes().to_vec();
92    cpath.push(0);
93    cpath
94}
sysinfo/unix/linux/utils.rs

sysinfo/unix/linux/
utils.rs
