blob: 4951e567023982a7eaecf75578d2d99e222af067 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
|
use crate::ffi::CString;
use crate::path::SMALL_PATH_BUFFER_SIZE;
use crate::{backend, io, path};
use alloc::vec::Vec;
#[cfg(not(target_os = "fuchsia"))]
use backend::fd::AsFd;
/// `chdir(path)`—Change the current working directory.
///
/// # References
/// - [POSIX]
/// - [Linux]
///
/// [POSIX]: https://pubs.opengroup.org/onlinepubs/9699919799/functions/chdir.html
/// [Linux]: https://man7.org/linux/man-pages/man2/chdir.2.html
#[inline]
pub fn chdir<P: path::Arg>(path: P) -> io::Result<()> {
path.into_with_c_str(backend::process::syscalls::chdir)
}
/// `fchdir(fd)`—Change the current working directory.
///
/// # References
/// - [POSIX]
/// - [Linux]
///
/// [POSIX]: https://pubs.opengroup.org/onlinepubs/9699919799/functions/fchdir.html
/// [Linux]: https://man7.org/linux/man-pages/man2/fchdir.2.html
#[cfg(not(target_os = "fuchsia"))]
#[inline]
pub fn fchdir<Fd: AsFd>(fd: Fd) -> io::Result<()> {
backend::process::syscalls::fchdir(fd.as_fd())
}
/// `getcwd()`—Return the current working directory.
///
/// If `reuse` is non-empty, reuse its buffer to store the result if possible.
///
/// # References
/// - [POSIX]
/// - [Linux]
///
/// [POSIX]: https://pubs.opengroup.org/onlinepubs/9699919799/functions/getcwd.html
/// [Linux]: https://man7.org/linux/man-pages/man3/getcwd.3.html
#[cfg(not(target_os = "wasi"))]
#[inline]
pub fn getcwd<B: Into<Vec<u8>>>(reuse: B) -> io::Result<CString> {
_getcwd(reuse.into())
}
fn _getcwd(mut buffer: Vec<u8>) -> io::Result<CString> {
// This code would benefit from having a better way to read into
// uninitialized memory, but that requires `unsafe`.
buffer.clear();
buffer.reserve(SMALL_PATH_BUFFER_SIZE);
buffer.resize(buffer.capacity(), 0_u8);
loop {
match backend::process::syscalls::getcwd(&mut buffer) {
Err(io::Errno::RANGE) => {
buffer.reserve(1); // use `Vec` reallocation strategy to grow capacity exponentially
buffer.resize(buffer.capacity(), 0_u8);
}
Ok(_) => {
let len = buffer.iter().position(|x| *x == b'\0').unwrap();
buffer.resize(len, 0_u8);
return Ok(CString::new(buffer).unwrap());
}
Err(errno) => return Err(errno),
}
}
}
|
