| 1 | //! Synchronization utilities. |
| 2 | |
| 3 | #![cfg_attr (not(target_os = "macos" ), allow(unused))] |
| 4 | |
| 5 | use std::{ |
| 6 | ops::{Deref, DerefMut}, |
| 7 | sync::atomic::*, |
| 8 | }; |
| 9 | |
| 10 | /// Makes the wrapped value [`Send`] + [`Sync`] even though it isn't. |
| 11 | pub struct SyncWrap<T> { |
| 12 | pub value: T, |
| 13 | } |
| 14 | |
| 15 | unsafe impl<T> Sync for SyncWrap<T> {} |
| 16 | |
| 17 | impl<T> Deref for SyncWrap<T> { |
| 18 | type Target = T; |
| 19 | |
| 20 | #[inline ] |
| 21 | fn deref(&self) -> &Self::Target { |
| 22 | &self.value |
| 23 | } |
| 24 | } |
| 25 | |
| 26 | impl<T> DerefMut for SyncWrap<T> { |
| 27 | #[inline ] |
| 28 | fn deref_mut(&mut self) -> &mut Self::Target { |
| 29 | &mut self.value |
| 30 | } |
| 31 | } |
| 32 | |
| 33 | impl<T> SyncWrap<T> { |
| 34 | #[inline ] |
| 35 | pub const unsafe fn new(value: T) -> Self { |
| 36 | Self { value } |
| 37 | } |
| 38 | } |
| 39 | |
| 40 | /// A convenience wrapper around `AtomicBool`. |
| 41 | pub(crate) struct AtomicFlag(AtomicBool); |
| 42 | |
| 43 | impl AtomicFlag { |
| 44 | #[inline ] |
| 45 | pub const fn new(value: bool) -> Self { |
| 46 | Self(AtomicBool::new(value)) |
| 47 | } |
| 48 | |
| 49 | #[inline ] |
| 50 | pub fn get(&self) -> bool { |
| 51 | self.0.load(order:Ordering::Relaxed) |
| 52 | } |
| 53 | |
| 54 | #[inline ] |
| 55 | pub fn set(&self, value: bool) { |
| 56 | self.0.store(val:value, order:Ordering::Relaxed); |
| 57 | } |
| 58 | } |
| 59 | |
| 60 | /// Prevents false sharing by aligning to the cache line. |
| 61 | #[derive (Clone, Copy)] |
| 62 | #[repr (align(64))] |
| 63 | pub(crate) struct CachePadded<T>(pub T); |
| 64 | |
| 65 | /// Alias to the atomic equivalent of `T`. |
| 66 | pub(crate) type Atomic<T> = <T as WithAtomic>::Atomic; |
| 67 | |
| 68 | /// A type with an associated atomic type. |
| 69 | pub(crate) trait WithAtomic { |
| 70 | type Atomic; |
| 71 | } |
| 72 | |
| 73 | #[cfg (target_has_atomic = "ptr" )] |
| 74 | impl WithAtomic for usize { |
| 75 | type Atomic = AtomicUsize; |
| 76 | } |
| 77 | |
| 78 | #[cfg (target_has_atomic = "ptr" )] |
| 79 | impl WithAtomic for isize { |
| 80 | type Atomic = AtomicIsize; |
| 81 | } |
| 82 | |
| 83 | #[cfg (target_has_atomic = "8" )] |
| 84 | impl WithAtomic for u8 { |
| 85 | type Atomic = AtomicU8; |
| 86 | } |
| 87 | |
| 88 | #[cfg (target_has_atomic = "8" )] |
| 89 | impl WithAtomic for i8 { |
| 90 | type Atomic = AtomicI8; |
| 91 | } |
| 92 | |
| 93 | #[cfg (target_has_atomic = "16" )] |
| 94 | impl WithAtomic for u16 { |
| 95 | type Atomic = AtomicU16; |
| 96 | } |
| 97 | |
| 98 | #[cfg (target_has_atomic = "16" )] |
| 99 | impl WithAtomic for i16 { |
| 100 | type Atomic = AtomicI16; |
| 101 | } |
| 102 | |
| 103 | #[cfg (target_has_atomic = "32" )] |
| 104 | impl WithAtomic for u32 { |
| 105 | type Atomic = AtomicU32; |
| 106 | } |
| 107 | |
| 108 | #[cfg (target_has_atomic = "32" )] |
| 109 | impl WithAtomic for i32 { |
| 110 | type Atomic = AtomicI32; |
| 111 | } |
| 112 | |
| 113 | #[cfg (target_has_atomic = "64" )] |
| 114 | impl WithAtomic for u64 { |
| 115 | type Atomic = AtomicU64; |
| 116 | } |
| 117 | |
| 118 | #[cfg (target_has_atomic = "64" )] |
| 119 | impl WithAtomic for i64 { |
| 120 | type Atomic = AtomicI64; |
| 121 | } |
| 122 | |