busy wait for macos

simu/src/wait.rs

@@ -0,0 +1,35 @@
+use std::sync::atomic::AtomicU32;
+
+#[cfg(feature = "futex")]
+use wait_on_address::AtomicWait;
+
+pub trait WaitOnAtomic {
+    fn wait(&self, v: u32);
+    fn signal(&self);
+}
+
+#[cfg(feature = "futex")]
+impl WaitOnAtomic for AtomicU32 {
+    fn wait(&self, v: u32) {
+        <AtomicU32 as AtomicWait>::wait(self, v);
+    }
+
+    fn signal(&self) {
+        self.notify_one();
+    }
+}
+
+#[cfg(not(feature = "futex"))]
+impl WaitOnAtomic for AtomicU32 {
+    fn wait(&self, v: u32) {
+        while self.load(std::sync::atomic::Ordering::Acquire) == v {
+            use std::{thread::sleep, time::Duration};
+
+            sleep(Duration::from_micros(500));
+        }
+    }
+
+    fn signal(&self) {
+        //
+    }
+}