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uv_platform/
host.rs

1//! Host system information (OS type, kernel release, distro metadata).
2
3use std::convert::Infallible;
4use std::fmt;
5use std::str::FromStr;
6
7/// The operating system type.
8#[derive(Debug, Clone, PartialEq, Eq)]
9pub enum OsType {
10    /// Linux, with the kernel type from `/proc/sys/kernel/ostype` (typically `"Linux"`).
11    Linux(String),
12    /// macOS / Darwin.
13    Darwin,
14    /// Windows.
15    Windows,
16}
17
18impl OsType {
19    /// Returns the operating system type for the current host.
20    ///
21    /// Returns `None` on unsupported platforms.
22    pub fn from_env() -> Option<Self> {
23        cfg_select! {
24            target_os = "linux" => {
25                fs_err::read_to_string("/proc/sys/kernel/ostype")
26                    .ok()
27                    .map(|s| Self::Linux(s.trim().to_string()))
28            },
29            target_os = "macos" => Some(Self::Darwin),
30            target_os = "windows" => Some(Self::Windows),
31            _ => None,
32        }
33    }
34}
35
36impl fmt::Display for OsType {
37    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
38        match self {
39            Self::Linux(os_type) => f.write_str(os_type),
40            Self::Darwin => f.write_str("Darwin"),
41            Self::Windows => f.write_str("Windows"),
42        }
43    }
44}
45
46/// The OS kernel release version.
47#[derive(Debug, Clone, PartialEq, Eq)]
48pub enum OsRelease {
49    /// Unix kernel release from `uname -r` (e.g., `"6.8.0-90-generic"`).
50    Unix(String),
51    /// Windows version major.minor.build.revision (e.g., `"10.0.26100.6901"`).
52    Windows {
53        major: u32,
54        minor: u32,
55        build: u32,
56        revision: u32,
57    },
58}
59
60impl OsRelease {
61    /// Returns the OS kernel release for the current host.
62    ///
63    /// Returns `None` on unsupported platforms or if the release cannot be read.
64    pub fn from_env() -> Option<Self> {
65        cfg_select! {
66            unix => {
67                let uname = rustix::system::uname();
68                let release = uname.release().to_str().ok()?;
69                Some(Self::Unix(release.to_string()))
70            },
71            windows => {
72                let os_version = windows_version::OsVersion::current();
73                Some(Self::Windows {
74                    major: os_version.major,
75                    minor: os_version.minor,
76                    build: os_version.build,
77                    revision: windows_version::revision(),
78                })
79            },
80            _ => None,
81        }
82    }
83}
84
85impl fmt::Display for OsRelease {
86    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
87        match self {
88            Self::Unix(release) => f.write_str(release),
89            Self::Windows {
90                major,
91                minor,
92                build,
93                revision,
94            } => write!(f, "{major}.{minor}.{build}.{revision}"),
95        }
96    }
97}
98
99/// Parsed fields from `/etc/os-release`.
100#[derive(Debug, Clone, Default)]
101pub struct LinuxOsRelease {
102    /// Distribution name (e.g., `"Ubuntu"`).
103    pub name: Option<String>,
104    /// Version identifier (e.g., `"22.04"`).
105    pub version_id: Option<String>,
106    /// Version codename (e.g., `"jammy"`).
107    pub version_codename: Option<String>,
108}
109
110impl LinuxOsRelease {
111    /// Reads and parses `/etc/os-release` on Linux, falling back to `/usr/lib/os-release`.
112    ///
113    /// See <https://www.freedesktop.org/software/systemd/man/latest/os-release.html>.
114    ///
115    /// Returns `None` on non-Linux platforms or if the file cannot be read.
116    pub fn from_env() -> Option<Self> {
117        cfg_select! {
118            target_os = "linux" => {
119                let content = fs_err::read_to_string("/etc/os-release")
120                    .or_else(|_| fs_err::read_to_string("/usr/lib/os-release"))
121                    .ok()?;
122                Some(content.parse().unwrap())
123            },
124            _ => None,
125        }
126    }
127}
128
129impl FromStr for LinuxOsRelease {
130    type Err = Infallible;
131
132    /// Parse the contents of an os-release file (KEY=VALUE format, optionally quoted).
133    fn from_str(contents: &str) -> Result<Self, Self::Err> {
134        let mut release = Self::default();
135        for line in contents.lines() {
136            let line = line.trim();
137            if line.is_empty() || line.starts_with('#') {
138                continue;
139            }
140            let Some((key, value)) = line.split_once('=') else {
141                continue;
142            };
143            let value = unquote(value);
144            match key {
145                "NAME" => release.name = Some(value.to_string()),
146                "VERSION_ID" => release.version_id = Some(value.to_string()),
147                "VERSION_CODENAME" => release.version_codename = Some(value.to_string()),
148                _ => {}
149            }
150        }
151        Ok(release)
152    }
153}
154
155/// Strip matching single or double quotes from a value.
156fn unquote(s: &str) -> &str {
157    for quote in ['"', '\''] {
158        if let Some(inner) = s.strip_prefix(quote).and_then(|s| s.strip_suffix(quote)) {
159            return inner;
160        }
161    }
162    s
163}
164
165#[cfg(test)]
166mod tests {
167    use insta::assert_debug_snapshot;
168
169    use super::*;
170
171    #[test]
172    fn test_parse_os_release_ubuntu() {
173        let contents = "\
174NAME=\"Ubuntu\"
175VERSION_ID=\"22.04\"
176VERSION_CODENAME=jammy
177ID=ubuntu
178";
179        let release: LinuxOsRelease = contents.parse().unwrap();
180        assert_debug_snapshot!(release, @r#"
181        LinuxOsRelease {
182            name: Some(
183                "Ubuntu",
184            ),
185            version_id: Some(
186                "22.04",
187            ),
188            version_codename: Some(
189                "jammy",
190            ),
191        }
192        "#);
193    }
194
195    #[test]
196    fn test_parse_os_release_empty() {
197        let release: LinuxOsRelease = "".parse().unwrap();
198        assert_eq!(release.name, None);
199        assert_eq!(release.version_id, None);
200        assert_eq!(release.version_codename, None);
201    }
202
203    #[test]
204    fn test_parse_os_release_comments_and_blanks() {
205        let contents = "\
206# This is a comment
207
208NAME='Fedora Linux'
209VERSION_ID=40
210";
211        let release: LinuxOsRelease = contents.parse().unwrap();
212        assert_eq!(release.name.as_deref(), Some("Fedora Linux"));
213        assert_eq!(release.version_id.as_deref(), Some("40"));
214        assert_eq!(release.version_codename, None);
215    }
216
217    #[test]
218    fn test_unquote() {
219        assert_eq!(unquote("\"hello\""), "hello");
220        assert_eq!(unquote("'hello'"), "hello");
221        assert_eq!(unquote("hello"), "hello");
222        assert_eq!(unquote("\"\""), "");
223        assert_eq!(unquote(""), "");
224    }
225
226    #[test]
227    fn test_os_type_returns_value() {
228        let os_type =
229            OsType::from_env().expect("OsType should be available on supported platforms");
230        cfg_select! {
231            target_os = "linux" => { assert!(matches!(os_type, OsType::Linux(_))); },
232            target_os = "macos" => { assert_eq!(os_type, OsType::Darwin); },
233            target_os = "windows" => { assert_eq!(os_type, OsType::Windows); },
234            _ => {},
235        }
236    }
237
238    #[test]
239    fn test_os_release_returns_value() {
240        let os_release =
241            OsRelease::from_env().expect("OsRelease should be available on supported platforms");
242        cfg_select! {
243            unix => { assert!(matches!(os_release, OsRelease::Unix(_))); },
244            windows => { assert!(matches!(os_release, OsRelease::Windows { .. })); },
245            _ => {},
246        }
247    }
248}