1 files changed, 21 insertions, 0 deletions
diff --git a/src/objective-c/GRPCClient/private/GRPCCompletionQueue.h b/src/objective-c/GRPCClient/private/GRPCCompletionQueue.h
new file mode 100644
index 0000000000..503df94dd4
--- /dev/null
+++ b/src/objective-c/GRPCClient/private/GRPCCompletionQueue.h
@@ -0,0 +1,21 @@
+#import <Foundation/Foundation.h>
+
+struct grpc_completion_queue;
+struct grpc_event;
+
+typedef void(^GRPCEventHandler)(struct grpc_event *event);
+
+// This class lets one more easily use grpc_completion_queue. To use it, pass
+// the value of the unmanagedQueue property of an instance of this class to
+// grpc_call_start_invoke. Then for every grpc_call_* method that accepts a tag,
+// you can pass a block of type GRPCEventHandler (remembering to cast it using
+// __bridge_retained). The block is guaranteed to eventually be called, by a
+// concurrent queue, and then released. Each such block is passed a pointer to
+// the grpc_event that carried it (in event->tag).
+// Release the GRPCCompletionQueue object only after you are not going to pass
+// any more blocks to the grpc_call that's using it.
+@interface GRPCCompletionQueue : NSObject
+@property(nonatomic, readonly) struct grpc_completion_queue *unmanagedQueue;
+
++ (instancetype)completionQueue;
+@end