blob: c46085e4505d5f1d3f89310bbcf17064f172084e (
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
|
use core::cell::UnsafeCell;
use core::mem::MaybeUninit;
use core::ptr;
pub(crate) struct UninitCell<T>(MaybeUninit<UnsafeCell<T>>);
impl<T> UninitCell<T> {
pub const fn uninit() -> Self {
Self(MaybeUninit::uninit())
}
pub unsafe fn as_mut_ptr(&self) -> *mut T {
(*self.0.as_ptr()).get()
}
#[allow(clippy::mut_from_ref)]
pub unsafe fn as_mut(&self) -> &mut T {
&mut *self.as_mut_ptr()
}
#[inline(never)]
pub unsafe fn write_in_place(&self, func: impl FnOnce() -> T) {
ptr::write(self.as_mut_ptr(), func())
}
pub unsafe fn drop_in_place(&self) {
ptr::drop_in_place(self.as_mut_ptr())
}
}
unsafe impl<T> Sync for UninitCell<T> {}
#[repr(transparent)]
pub struct SyncUnsafeCell<T> {
value: UnsafeCell<T>,
}
unsafe impl<T: Sync> Sync for SyncUnsafeCell<T> {}
impl<T> SyncUnsafeCell<T> {
#[inline]
pub const fn new(value: T) -> Self {
Self {
value: UnsafeCell::new(value),
}
}
pub unsafe fn set(&self, value: T) {
*self.value.get() = value;
}
pub unsafe fn get(&self) -> T
where
T: Copy,
{
*self.value.get()
}
}
|
