From 66ee8a34f3bcde31f9d5919f2e0e363ac11f4aca Mon Sep 17 00:00:00 2001
From: Christian Cunningham <cc@localhost>
Date: Thu, 18 Aug 2022 20:37:09 -0700
Subject: Formatted printing to UART

---
 src/sync.rs | 33 +++++++++++++++++++++++++++++++++
 1 file changed, 33 insertions(+)
 create mode 100644 src/sync.rs

(limited to 'src/sync.rs')

diff --git a/src/sync.rs b/src/sync.rs
new file mode 100644
index 0000000..2b7e1ff
--- /dev/null
+++ b/src/sync.rs
@@ -0,0 +1,33 @@
+pub mod interface {
+	pub trait Mutex {
+		type Data;
+		fn lock<'a, R>(&'a self, f: impl FnOnce(&'a mut Self::Data) -> R) -> R;
+	}
+}
+
+use core::cell::UnsafeCell;
+
+pub struct NullLock<T> where T: ?Sized {
+	data: UnsafeCell<T>,
+}
+
+unsafe impl<T> Send for NullLock<T> where T: ?Sized + Send {}
+unsafe impl<T> Sync for NullLock<T> where T: ?Sized + Send {}
+
+impl<T> NullLock<T> {
+	pub const fn new(data: T) -> Self {
+		Self {
+			data: UnsafeCell::new(data),
+		}
+	}
+}
+
+impl<T> interface::Mutex for NullLock<T> {
+	type Data = T;
+
+	fn lock<'a, R>(&'a self, f: impl FnOnce(&'a mut T) -> R) -> R {
+		let data = unsafe { &mut *self.data.get() };
+
+		f(data)
+	}
+}
-- 
cgit v1.2.1