| use crate::cell::UnsafeCell; |
| |
| pub struct Mutex { |
| locked: UnsafeCell<bool>, |
| } |
| |
| unsafe impl Send for Mutex {} |
| unsafe impl Sync for Mutex {} // no threads on wasm |
| |
| impl Mutex { |
| pub const fn new() -> Mutex { |
| Mutex { locked: UnsafeCell::new(false) } |
| } |
| |
| #[inline] |
| pub unsafe fn init(&mut self) { |
| } |
| |
| #[inline] |
| pub unsafe fn lock(&self) { |
| let locked = self.locked.get(); |
| assert!(!*locked, "cannot recursively acquire mutex"); |
| *locked = true; |
| } |
| |
| #[inline] |
| pub unsafe fn unlock(&self) { |
| *self.locked.get() = false; |
| } |
| |
| #[inline] |
| pub unsafe fn try_lock(&self) -> bool { |
| let locked = self.locked.get(); |
| if *locked { |
| false |
| } else { |
| *locked = true; |
| true |
| } |
| } |
| |
| #[inline] |
| pub unsafe fn destroy(&self) { |
| } |
| } |
| |
| // All empty stubs because wasm has no threads yet, so lock acquisition always |
| // succeeds. |
| pub struct ReentrantMutex { |
| } |
| |
| impl ReentrantMutex { |
| pub unsafe fn uninitialized() -> ReentrantMutex { |
| ReentrantMutex { } |
| } |
| |
| pub unsafe fn init(&mut self) {} |
| |
| pub unsafe fn lock(&self) {} |
| |
| #[inline] |
| pub unsafe fn try_lock(&self) -> bool { |
| true |
| } |
| |
| pub unsafe fn unlock(&self) {} |
| |
| pub unsafe fn destroy(&self) {} |
| } |