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-rw-r--r--src/checked.rs78
1 files changed, 0 insertions, 78 deletions
diff --git a/src/checked.rs b/src/checked.rs
deleted file mode 100644
index ec4114d..0000000
--- a/src/checked.rs
+++ /dev/null
@@ -1,78 +0,0 @@
-//! Safe, run-time checked resources
-
-use core::marker::PhantomData;
-use core::cell::UnsafeCell;
-
-use cortex_m::interrupt;
-use cortex_m::register::{basepri, basepri_max};
-use vcell::VolatileCell;
-
-use Ceiling;
-
-unsafe fn acquire(locked: &VolatileCell<bool>, ceiling: u8) -> u8 {
- assert!(!locked.get(), "resource already locked");
- let old_basepri = basepri::read();
- basepri_max::write(ceiling);
- locked.set(true);
- old_basepri
-}
-
-unsafe fn release(locked: &VolatileCell<bool>, old_basepri: u8) {
- locked.set(false);
- basepri::write(old_basepri);
-}
-
-/// A totally safe `Resource` that panics on misuse
-pub struct Resource<T, C> {
- _marker: PhantomData<C>,
- data: UnsafeCell<T>,
- locked: VolatileCell<bool>,
-}
-
-impl<T, C> Resource<T, C>
-where
- C: Ceiling,
-{
- /// Creates a new `Resource` with ceiling `C`
- pub const fn new(data: T) -> Resource<T, C> {
- Resource {
- _marker: PhantomData,
- data: UnsafeCell::new(data),
- locked: VolatileCell::new(false),
- }
- }
-
- /// Locks the resource, blocking tasks with priority equal or smaller than
- /// the ceiling `C`
- pub fn lock<R, F>(&'static self, f: F) -> R
- where
- F: FnOnce(&T) -> R,
- {
- unsafe {
- let old_basepri = acquire(&self.locked, C::hw_ceiling());
- ::compiler_barrier();
- let ret = f(&*self.data.get());
- ::compiler_barrier();
- release(&self.locked, old_basepri);
- ret
- }
- }
-
- /// Mutably locks the resource, blocking tasks with priority equal or
- /// smaller than the ceiling `C`
- pub fn lock_mut<R, F>(&'static self, f: F) -> R
- where
- F: FnOnce(&mut T) -> R,
- {
- unsafe {
- let old_basepri = acquire(&self.locked, C::hw_ceiling());
- ::compiler_barrier();
- let ret = f(&mut *self.data.get());
- ::compiler_barrier();
- release(&self.locked, old_basepri);
- ret
- }
- }
-}
-
-unsafe impl<T, C> Sync for Resource<T, C> {}