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
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
|
//! Beginning with macOS 10.13, `utimensat` is supported by the OS, so here, we check if the symbol exists
//! and if not, we fallback to `utimes`.
use crate::FileTime;
use libc::{c_char, c_int, timespec};
use std::ffi::{CStr, CString};
use std::fs::File;
use std::os::unix::prelude::*;
use std::path::Path;
use std::sync::atomic::AtomicUsize;
use std::sync::atomic::Ordering::SeqCst;
use std::{io, mem};
pub fn set_file_times(p: &Path, atime: FileTime, mtime: FileTime) -> io::Result<()> {
set_times(p, Some(atime), Some(mtime), false)
}
pub fn set_file_mtime(p: &Path, mtime: FileTime) -> io::Result<()> {
set_times(p, None, Some(mtime), false)
}
pub fn set_file_atime(p: &Path, atime: FileTime) -> io::Result<()> {
set_times(p, Some(atime), None, false)
}
pub fn set_file_handle_times(
f: &File,
atime: Option<FileTime>,
mtime: Option<FileTime>,
) -> io::Result<()> {
// Attempt to use the `futimens` syscall, but if it's not supported by the
// current kernel then fall back to an older syscall.
if let Some(func) = futimens() {
let times = [super::to_timespec(&atime), super::to_timespec(&mtime)];
let rc = unsafe { func(f.as_raw_fd(), times.as_ptr()) };
if rc == 0 {
return Ok(());
} else {
return Err(io::Error::last_os_error());
}
}
super::utimes::set_file_handle_times(f, atime, mtime)
}
pub fn set_symlink_file_times(p: &Path, atime: FileTime, mtime: FileTime) -> io::Result<()> {
set_times(p, Some(atime), Some(mtime), true)
}
fn set_times(
p: &Path,
atime: Option<FileTime>,
mtime: Option<FileTime>,
symlink: bool,
) -> io::Result<()> {
// Attempt to use the `utimensat` syscall, but if it's not supported by the
// current kernel then fall back to an older syscall.
if let Some(func) = utimensat() {
let flags = if symlink {
libc::AT_SYMLINK_NOFOLLOW
} else {
0
};
let p = CString::new(p.as_os_str().as_bytes())?;
let times = [super::to_timespec(&atime), super::to_timespec(&mtime)];
let rc = unsafe { func(libc::AT_FDCWD, p.as_ptr(), times.as_ptr(), flags) };
if rc == 0 {
return Ok(());
} else {
return Err(io::Error::last_os_error());
}
}
super::utimes::set_times(p, atime, mtime, symlink)
}
fn utimensat() -> Option<unsafe extern "C" fn(c_int, *const c_char, *const timespec, c_int) -> c_int>
{
static ADDR: AtomicUsize = AtomicUsize::new(0);
unsafe {
fetch(&ADDR, CStr::from_bytes_with_nul_unchecked(b"utimensat\0"))
.map(|sym| mem::transmute(sym))
}
}
fn futimens() -> Option<unsafe extern "C" fn(c_int, *const timespec) -> c_int> {
static ADDR: AtomicUsize = AtomicUsize::new(0);
unsafe {
fetch(&ADDR, CStr::from_bytes_with_nul_unchecked(b"futimens\0"))
.map(|sym| mem::transmute(sym))
}
}
fn fetch(cache: &AtomicUsize, name: &CStr) -> Option<usize> {
match cache.load(SeqCst) {
0 => {}
1 => return None,
n => return Some(n),
}
let sym = unsafe { libc::dlsym(libc::RTLD_DEFAULT, name.as_ptr() as *const _) };
let (val, ret) = if sym.is_null() {
(1, None)
} else {
(sym as usize, Some(sym as usize))
};
cache.store(val, SeqCst);
return ret;
}
|
