Add rust kext to the mono repo

windows_kext/driver/src/array_holder.rs

@@ -0,0 +1,25 @@
+use core::cell::RefCell;
+
+use alloc::vec::Vec;
+
+pub struct ArrayHolder(RefCell<Option<Vec<u8>>>);
+unsafe impl Sync for ArrayHolder {}
+
+impl ArrayHolder {
+    pub const fn default() -> Self {
+        Self(RefCell::new(None))
+    }
+
+    pub fn save(&self, data: &[u8]) {
+        if let Ok(mut opt) = self.0.try_borrow_mut() {
+            opt.replace(data.to_vec());
+        }
+    }
+
+    pub fn load(&self) -> Option<Vec<u8>> {
+        if let Ok(mut opt) = self.0.try_borrow_mut() {
+            return opt.take();
+        }
+        None
+    }
+}