waterui_cli/
utils.rs

1//! Utility functions for the CLI.
2
3use std::{
4    io,
5    path::{Path, PathBuf},
6    process::Output,
7    process::Stdio,
8    sync::atomic::{AtomicBool, Ordering},
9};
10
11use color_eyre::eyre;
12use smol::{process::Command, unblock};
13
14/// Locate an executable in the system's PATH.
15///
16/// Return the path to the executable if found.
17///
18/// # Errors
19/// - If the executable is not found in the PATH.
20pub(crate) async fn which(name: &'static str) -> Result<PathBuf, which::Error> {
21    unblock(move || which::which(name)).await
22}
23
24/// Enable or disable standard output for command executions.
25///
26/// By default, standard output is disabled.
27static STD_OUTPUT: AtomicBool = AtomicBool::new(false);
28
29/// Enable or disable standard output for command executions.
30pub fn set_std_output(enabled: bool) {
31    STD_OUTPUT.store(enabled, std::sync::atomic::Ordering::SeqCst);
32}
33
34pub(crate) fn command(command: &mut Command) -> &mut Command {
35    command
36        .kill_on_drop(true)
37        .stdout(if STD_OUTPUT.load(Ordering::SeqCst) {
38            Stdio::inherit()
39        } else {
40            Stdio::piped()
41        })
42        .stderr(if STD_OUTPUT.load(Ordering::SeqCst) {
43            Stdio::inherit()
44        } else {
45            Stdio::piped()
46        })
47}
48
49/// Run a command and capture its output regardless of exit status.
50///
51/// When `STD_OUTPUT` is enabled, also prints to terminal.
52///
53/// # Errors
54/// - If the command fails to execute.
55pub(crate) async fn run_command_output(
56    name: &str,
57    args: impl IntoIterator<Item = &str>,
58) -> eyre::Result<Output> {
59    let result = Command::new(name)
60        .args(args)
61        .kill_on_drop(true)
62        .stdout(Stdio::piped())
63        .stderr(Stdio::piped())
64        .output()
65        .await?;
66
67    // If STD_OUTPUT is enabled, also print to terminal
68    if STD_OUTPUT.load(Ordering::SeqCst) {
69        use std::io::Write;
70        let _ = std::io::stdout().write_all(&result.stdout);
71        let _ = std::io::stderr().write_all(&result.stderr);
72    }
73
74    Ok(result)
75}
76
77/// Run a command with the specified name and arguments.
78///
79/// Always captures output. When `STD_OUTPUT` is enabled, also prints to terminal.
80///
81/// Return the standard output as a `String` if successful.
82/// # Errors
83/// - If the command fails to execute or returns a non-zero exit status.
84pub(crate) async fn run_command(
85    name: &str,
86    args: impl IntoIterator<Item = &str>,
87) -> eyre::Result<String> {
88    let result = run_command_output(name, args).await?;
89
90    if result.status.success() {
91        Ok(String::from_utf8_lossy(&result.stdout).to_string())
92    } else {
93        Err(eyre::eyre!(
94            "Command {} failed with status {}",
95            name,
96            result.status
97        ))
98    }
99}
100
101/// Parse whitespace-separated u32 values (e.g., process IDs).
102pub(crate) fn parse_whitespace_separated_u32s(input: &str) -> Vec<u32> {
103    input
104        .split_whitespace()
105        .filter_map(|part| part.parse::<u32>().ok())
106        .collect()
107}
108
109/// Async file copy using reflink when available, falling back to regular copy.
110///
111/// This is more efficient than regular copy on filesystems that support reflinks (APFS, Btrfs).
112///
113/// # Errors
114/// - If the copy operation fails.
115pub async fn copy_file(from: impl AsRef<Path>, to: impl AsRef<Path>) -> io::Result<()> {
116    let from = from.as_ref().to_path_buf();
117    let to = to.as_ref().to_path_buf();
118    unblock(move || reflink::reflink_or_copy(from, to).map(|_| ())).await
119}
120
121#[cfg(test)]
122mod tests {
123    use super::parse_whitespace_separated_u32s;
124
125    #[test]
126    fn parses_pidof_output_with_multiple_pids() {
127        let parsed = parse_whitespace_separated_u32s("123 456\n");
128        assert_eq!(parsed, vec![123, 456]);
129    }
130
131    #[test]
132    fn ignores_non_numeric_tokens() {
133        let parsed = parse_whitespace_separated_u32s("foo 42 bar\n");
134        assert_eq!(parsed, vec![42]);
135    }
136}
waterui_cli/utils.rs

waterui_cli/
utils.rs
