Revert "Revert "Class-ify lockfree event""

1 files changed, 25 insertions, 19 deletions

diff --git a/src/core/lib/iomgr/lockfree_event.h b/src/core/lib/iomgr/lockfree_event.h
index 75526d6b9f..47d0089c01 100644
--- a/src/core/lib/iomgr/lockfree_event.h
+++ b/src/core/lib/iomgr/lockfree_event.h
@@ -25,24 +25,30 @@
 
 #include "src/core/lib/iomgr/exec_ctx.h"
 
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-void grpc_lfev_init(gpr_atm* state);
-void grpc_lfev_destroy(gpr_atm* state);
-bool grpc_lfev_is_shutdown(gpr_atm* state);
-
-void grpc_lfev_notify_on(grpc_exec_ctx* exec_ctx, gpr_atm* state,
-                         grpc_closure* closure, const char* variable);
-/* Returns true on first successful shutdown */
-bool grpc_lfev_set_shutdown(grpc_exec_ctx* exec_ctx, gpr_atm* state,
-                            grpc_error* shutdown_err);
-void grpc_lfev_set_ready(grpc_exec_ctx* exec_ctx, gpr_atm* state,
-                         const char* variable);
-
-#ifdef __cplusplus
-}
-#endif
+namespace grpc_core {
+
+class LockfreeEvent {
+ public:
+  LockfreeEvent() = default;
+  ~LockfreeEvent();
+
+  LockfreeEvent(const LockfreeEvent&) = delete;
+  LockfreeEvent& operator=(const LockfreeEvent&) = delete;
+
+  bool IsShutdown() const {
+    return (gpr_atm_no_barrier_load(&state_) & kShutdownBit) != 0;
+  }
+
+  void NotifyOn(grpc_exec_ctx* exec_ctx, grpc_closure* closure);
+  bool SetShutdown(grpc_exec_ctx* exec_ctx, grpc_error* error);
+  void SetReady(grpc_exec_ctx* exec_ctx);
+
+ private:
+  enum State { kClosureNotReady = 0, kClosureReady = 2, kShutdownBit = 1 };
+
+  gpr_atm state_ = kClosureNotReady;
+};
+
+}  // namespace grpc_core
 
 #endif /* GRPC_CORE_LIB_IOMGR_LOCKFREE_EVENT_H */