1 files changed, 42 insertions, 0 deletions
diff --git a/library/std/src/sys/sgx/condvar.rs b/library/std/src/sys/sgx/condvar.rs
new file mode 100644
index 00000000000..ed6dbcf4971
--- /dev/null
+++ b/library/std/src/sys/sgx/condvar.rs
@@ -0,0 +1,42 @@
+use crate::sys::mutex::Mutex;
+use crate::time::Duration;
+
+use super::waitqueue::{SpinMutex, WaitQueue, WaitVariable};
+
+pub struct Condvar {
+    inner: SpinMutex<WaitVariable<()>>,
+}
+
+impl Condvar {
+    pub const fn new() -> Condvar {
+        Condvar { inner: SpinMutex::new(WaitVariable::new(())) }
+    }
+
+    #[inline]
+    pub unsafe fn init(&mut self) {}
+
+    #[inline]
+    pub unsafe fn notify_one(&self) {
+        let _ = WaitQueue::notify_one(self.inner.lock());
+    }
+
+    #[inline]
+    pub unsafe fn notify_all(&self) {
+        let _ = WaitQueue::notify_all(self.inner.lock());
+    }
+
+    pub unsafe fn wait(&self, mutex: &Mutex) {
+        let guard = self.inner.lock();
+        WaitQueue::wait(guard, || mutex.unlock());
+        mutex.lock()
+    }
+
+    pub unsafe fn wait_timeout(&self, mutex: &Mutex, dur: Duration) -> bool {
+        let success = WaitQueue::wait_timeout(&self.inner, dur, || mutex.unlock());
+        mutex.lock();
+        success
+    }
+
+    #[inline]
+    pub unsafe fn destroy(&self) {}
+}